A comparison of peak power reduction schemes for OFDM
电力电子翻译
Silicon Carbide MOSFETs Challenge IGBTsSiC technology has undergone significant improvements that now allow fabrication of MOSFETs capable of outperforming their Si IGBT cousins, particularly at high power and high temperaturesIn light of recent silicon carbide (SiC) technology advances, commercial production of 1200-V 4H-SiC[1] power MOSFETs is now feasible. There have been improvements in 4H-SiC substrate quality and epitaxy, optimized device designs and fabrication processes, plus increased channel mobility with nitridation annealing.[2] SiC is a better power semiconductor than Si, because of a 10-times higher electric-field breakdown capability, higher thermal conductivity and higher temperature operation capability due to a wide electronic bandgap.SiC excels over Si as a semiconductor material in 600-V and higher-rated breakdown voltage devices. SiC Schottky diodes at 600-V and 1200-V ratings are commercially available today and are already accepted as the best solution for efficiency improvement in boost converter topologies. In addition, these diodes find use in solar inverters, because they have lower switching losses than the Si PIN freewheeling diodes now used in that application.At 600-V and 1200-V ratings, IGBTs have been the switch of choice for power conversion. Previously, Si MOSFETs were handicapped in those applications by their high on-resistance (R DSON). At high breakdown voltages, R DSON increases approximately with the square of the drain-source breakdown voltageV DSMAX.[3] The R DSON of a MOSFET consists of the sum of the channel resistance, the inherent JFET resistance and the drift resistance (Fig. 1). The drift resistance (R DRIFT) is the dominant portion of the overall resistance, where d equalsdrift-layer thickness, q equals electron charge, ìn equals channel mobility andN D equals doping factor.The new generation of SiC MOSFETs cuts drift-layer thickness by nearly a factor of 10 while simultaneously enabling the doping factor to increase by the same order of magnitude. The overall effect results in a reduction of the drift resistance to 1/100th of its Si MOSFET equivalent.The improved SiC MOSFET discussed here is an engineering sample of a 1200-V, 20-A device with a 100-mV R DSON at a 15-V gate-source voltage. Besides its inherent reduction in on-resistance, SiC also offers a substantially reducedon-resistance variation over its operating temperature. From 25°C to 150°C, SiCvariations are in the range of 20%, compared with 200% to 300% for Si. The SiC MOSFET die is capable of operation at junction temperatures greater than 200°C, but the engineering sample is limited in temperature to 150°C by its TO-247plastic package.Compared with a Si IGBT, a SiC MOSFET has a substantial advantage inconduction losses, particularly at lower power outputs. By virtue of its unipolar nature, it has no tail currents at turn-off, thereby leading to greatly reducedturn-off losses. Table 1 shows the switching loss difference when compared with a standard off-the-shelf 1200-V IGBT.The switching losses of a SiC MOSFET are less than half those of a Si IGBT (1.14 mJ versus 2.6 mJ, respectively). Combining this switching-loss reduction with the lower overall conduction losses, it is clear that the SiC switch is a much moreefficient device for high-power-conversion systems.Three-Phase Solar InverterTo demonstrate its application as a solar inverter, a 7-kW, 16.6-kHz three-phase grid-connected system was implemented. This B6 topology, developed by the Fraunhofer Institute ISE, uses a split-link dc capacitor with a connection of the neutral conductor to the center point of both capacitors. The unit connects to a 400-V grid, using 1200-V IGBTs as the standard power-conversion devices. These IGBTs were replaced by 1200-V SiC MOSFETs, and the significant performance difference is clearly visible in Fig. 2. Table 2 shows the maximum efficiency and European-efficiency improvements that were achieved.As seen by the Fig. 2 curves, the SiC devices offer a performance advantage over their Si IGBT counterparts. Maximum efficiency increased by 1.92%, and theoverall Euro-efficiency rating improved by 2.36%. This equates to a 50%reduction in overall losses in the system.Another performance-parameter improvement of note was the system's reduction in heatsink temperature at full-rated power output. At a 25°C ambient, the final steady-state heatsink temperature with the IGBTs was 93°C versus 50°C with the SiC MOSFETs.[3]There are several different ways of looking at the system benefits obtainable by using a full SiC-based solution in a photovoltaic (PV) power converter:Cost of inductive componentsThe volume of an inductive component depends most significantly on the system switching frequency. A good approximation is a reduction close to the reciprocal of the times factor increase in switching frequency, taking into account filling factor and winding technique. The cost of inductive components decreases by about 50% for a two to three times increase in switching frequency (which isentirely possible with this technology). To keep the third harmonic beneath the lower conducted emission floor of 150 kHz, the practical limit for hard switching is just below 50 kHz in these systems.∙Reduced cooling requirementsReductions of up to 50% or more in heatsink temperature are possible with this technology. A comparable reduction in heatsink sizing is possible while stillmaintaining the higher-efficiency advantage that this technology enables. This solar inverter example of reduction in heatsink sizing should allow a reduction in production cost of around 5%, while still delivering increased annual benefitthrough feed-in tariffs from the grid. A feed-in tariff is an incentive structure to encourage the adoption of renewable energy through government legislation.∙Annual feed-in benefitA common PV system with 7 kW in Germany produces approximately 7000 kWhper year with a feed-in tariff of 0.49 euro/kWh. (In June 2008, the euroapproximately was worth US$1.60.) The annual benefit is approximately 3430 euros. The three-phase inverter given in the previous example showed an increase in Euro efficiency of 2.36%. This equates to an annual gain of 81 euros per year with this particular system. This is the estimation for central Europe. However, if looking at southern Europe, where the irradiation level is about twice that inGermany, the annual benefit can be even greater, as shown in Table 3.[4]Three-Phase High-Power-Factor RectifierA three-phase six-switch rectifier整流器followed by an isolated隔离的；孤独的；单独的；偏远的dc-dc converter变换器is typically used in three-phase applications that require high power factor (HPF) and galvanic isolation电隔离between input and output. The rectifier shown in Fig. 3 (a 3-kW zero current switching resonant topology) can achieve the same goal with only two switches. When switches S1 and S2 are turned on, the stored energy in C1 to C3 is quickly moved to thesecondary-side resonant capacitor (C D) through the transformer (T R) andresonant共振的inductor (L R). The discharging time is designed to beapproximately equal to one-half of the resonant period (T O). For an optimaldesign, T O should be relatively shorter than the switching period (T S) to achieve a low total harmonic distortion谐振失真.The system was run initially最初，首先；开头at full load全负荷with a pair of standard 1200-V, 25-A-rated IGBTs. These devices were then replaced by a pair of standard 1200-V, 40-A IGBTs, and the system was re-run at full load. The efficiency versus output power功率输出curves 曲线were recorded.The IGBTs were then replaced by a pair of 1200-V, 20-A-rated SiC MOSFETs and the exercise repeated. As seen in Fig. 4, the SiC devices resulted in导致a 2.2% increase in efficiency at a 3-kW output and substantial efficiency improvement 重大的效率改进throughout the entire load curve负荷曲线. Also of note was a 25°C case-temperature reduction with the MOSFETs versus 对，相对the 40-A-rated IGBTs and a 36°C difference when compared with the 25-A-rated devices.[5]10-kV, 10-A SiC MOSFET in a Boost ConverterSiC technology shows significant improvements in the 1200-V MOSFET arena, as revealed in the two previous examples. The performance improvement becomes even greater when compared to Si power switches rated at 6.5 kV and above.Recently developed was a 10-kV, 10-A SiC MOSFET. The 10-kV device exhibits a drain-source forward voltage漏源极正向电压drop of only 4.1 V, while conducting当导通full-rated 10-A drain current with a 20-V gate-source voltage. This is equivalent to a specific on-resistance characteristic电阻特性of only 127 mV/cm2. The drain-source leakage current measured 124 nA at a 10-kV blocking voltage. In a direct comparison with a standard 6.5-kV Si IGBT in a clamped inductive switching test fixture, a SiC MOSFET exhibited 1/200th of the total switching energy of the IGBT. This unipolar SiC MOSFET's turn-on delay time was only 94 ns compared with 1.4 ìs for the IGBT and the turn-off time was only 50 ns instead of the IGBT's 540 ns.To analyze in-circuit performance, a 10-kV SiC MOSFET was combined with a 10-kV SiC Schottky diode and an air-core inductor in a standard boost-circuit topology (Fig. 5). The circuit was designed to boost a 500-Vdc input to a 5-kVdc output at a switching frequency of 20 kHz. The system ran at 91% efficiency throughout the power band up to 600 W. Considering that this same circuit with 考虑同样用标准Si MOSFET 开关的电路standard Si MOSFET switches would only be capable of能够运行在几百赫兹的开关平率下a few hundred Hertz switching frequency, there is 将有更显著的性能提高应用SiC 材料在这个电压水平an even greater performance advantage with SiC material at these voltagelevels. The waveform shown in Fig. 6 exhibits the exceptionally fast turn-offtransient of this system.[6]With the most recent advancements in SiC materials processing加工and device design, it will soon be possible to produce reliable MOSFET switches for the commercial marketplace. Considering the recent surge in interest in alternative energy systems, SiC technology is now ready to further improve their benefits.The reduction in power losses 减少能源损耗，that this technology will provide 提供，供给in a PV system's power conversion section这项技术将在光伏系统的功率转换部分提供应用will enable more efficient usage使用of PV panel energy光伏板能量,将使光伏电池的能量更有效地使用in turn providing more power to the grid and allowing a reduction in future fossil-fuel generation在向电网提供更多的权力，允许在未来减少化石燃料发电.References1.4H refers to the SiC crystalline structure used in power semiconductors.2.Hull, Brett, et al. “Status of 1200 V 4H-SiC Power DMOSFETs,”International Semiconductor Device Research Symposium, December 2007.3.Burger, B.; Kranzer, D.; Stalter, O.; and Lehrmann, S. “Silicon Carbide(SiC) D-MOS for Grid-Feeding Solar-Inverters,” Fraunhofer Institute, EPE 2007, September 2007.4.Burger, B.; Kranzer, D.; and Stalter, O. “Cost Reducti on of PV Inverterswith SiC DMOSFETs,” Fraunhofer Institute, 5th International Conference onIntegrated Power Electronics Systems, March 2008.5.Yang, Yungtaek; Dillman, David L.; and Jovanovic, Milan M.“Performance Evaluation of Silicon Carbide MOSFET in T hree-PhaseHigh-Power-Factor Rectifier,” Power Electronics Laboratory, DeltaProducts, .6.Das, Mrinal K., et al. “State-of-the-Art 10-kV NMOS Transistors,”20th Annual International Symposium on Power Semiconductor Devices and ICs, May 2008.碳化硅MOSFETs挑战IGBTCs出处:/discrete-power-semis/silicon-ca rbide-mosfets-challenge-igbtsMichael O'Neill, Applications Engineering Manager, CREE, Durham, N.C.摘要:SiC技术经历了显著的改善和提高,使现在允许制造MOSFET的性能优于他们的表兄弟Si IGBT,特别是在大功率和高温方面。
涡轮增压器英文文献2
1. INTRODUCTIONThe requirements of modern truck engines increase with each step of the emissionlegislation. In the same way the charging system as a part of the air management system has to be improved. This leads to more and more complicated solutions such as Regulated – Two – Stage (R2S), combinations of super- and turbochargers (e.g. eBooster) and turbos with Variable Turbine Geometry (VTG).In particular the VTG is a solution of highest interest because it is able to fulfil most of the required development objectives for commercial diesel engines as• Higher torque (boost pressure) at low engine speeds • Better transient response (drivability) • BSFC improvement• Drive EGR at part and full load to reduce emissionsAn additional advantage compared to other systems is that the installation dimensions are nearly the same as the standard (waste-gated) turbocharger.Never the less this excellent tool for a controllable air management system, even after two decades of development never found access to the large truck fleets world wide! During all steps of emission legislation many customers showed interest and made tests with the product, but in the end nearly always a maybe less comfortable but cheaper solution was introduced to series production because VTG was a … nice to have“ and not a …must“.To launch the VTG, an additional feature to increase the benefit for the customers was required. As a new objective, the use of the VTG for engine braking was defined. The prospects of additional benefits for the customers were:• Replacement of state-of-the-art engine brake systems (brake flap, Jake Brake) • Reduction of total system weight• Increase of brake power at low engine speeds • Increase of maximum brake power• Option of replacing retarders at high engine speedsThe requirements of several customers are summarised in the following charts:0%20%40%60%80%100%120%140%40%60%80%100%120%140%Engine speed / max speed under fired conditionsB r a k i n g (e n g i n e ) p o w e r / r a t e d p o w e rFigure 1a: Comparison of braking performance and rated power0%20%40%60%80%100%120%-55101520253035Time [s]B r a k i n g T o r q u e / B r a k i n g T o r q u e m a xFigure 1b: Time to build up braking powerThis means in figures: • Ratio rated power / maximum brake power 1,00 (1,30) • Increase of brake power at 60% - 90% 50 % (80%)of maximum engine speed• Time to achieve 80% of brake power at 5 sec (3 sec)40% - 100% of maximum engine speed• Share of braking cycle to total operating time 10% (20%)The first values show the average requirement, those in brackets the peak targets.To achieve these target values for the engine, the turbocharger has to fulfil the following requirements under braking conditions:• Mean back pressure of the turbine 5 bar (7 bar) • Peak back pressure of the turbine 8 bar (11 bar) • Time for one full stroke of the actuator 0,3 s (0,2 s) • Number of actuations in life of engine (millions)- full strokes 0,6 (1,0) - part strokes 4,5 (9,0)For this a new development was started in 1996.2. DESIGN CONCEPT OF BORG WARNER’S VTG FOR CDThe VTG described below is based on a Standard turbocharger. The compressor side (1) is practically the same; the only difference in the core assembly (2) is the additional speed sensor (3), which is fitted to the center housing for permanent control of the turbocharger speed.The actual VTG is based on a swing – vane design, where the performance and the mass flow of the turbine is influenced by changes of the flow angle to the wheel by means of moving the vanes.6731813121928Figure 2: Exploded view to VTG turbochargerThe design features are as follows:• Single flow turbine housing (4) for maximal flow• Vane ring assembly (5) consisting of 13 dual – axis curved vanes (6), pivoted between an inner and outer vane ring (7). Three spacers (8) make sure that minimal axial clearances can be achieved.• Vane levers (9) for moving the vanes designed as a fork. Adjustment is done by pivoted sliding blocks (10), which are positioned in the fork.• Adjustment ring assembly (11) having 13 small sliding blocks for actuating the vanes anda large one on the opposite side to actuate the whole ring. The adjustment ring iscentered by six rollers (12), which are equally spaced by a cage (13).• Adjustment shaft (14), which transmits the actuating forces via adjustment lever (15) to the actuator rod (16). The fork connection to the large sliding block is similar to the small sliding block / vane fork interface. Two flats situated between a pair of bearing bushes accommodate the action of the adjustment lever.• Adjustment lever connected to the actuator rod with a bolt and two curved areas to define the contact to the adjustable fixing screws (17) which define the stop for maximal and minimal vane position.• Actuator flange (18) which closes the turbine stage and allows fixing of the core assembly. The flange also includes a mounting bracket for the actuator (19) and contains the bearing of the adjustment shaft and the stops.3. TURBINE HOUSING / ACTUATOR FLANGE3.1 Technical ChallengesThe turbine housing and the actuator flange contain the whole VTG mechanism. Therefore, the prime task for these two parts is to avoid sticking of any of the moving parts. This must be assured at low and high temperatures and at transient temperature changes combined with extremely high back pressures, which occur simultaniously under braking conditions. Under the same conditions a second task is also important and difficult to achieve: To avoid losses by leakage, the two parts have to keep sealed at all contact areas.If the design of the housing and the flange is not correct, a damage mechanism will occur as follows: Due to the high temperature changes between fired and braking mode the turbine housing will extend extremely. If the temperature distribution is inhomogeneous because the material distribution is, then high stress will occur at locations with high mass concentration. Additionally due to the high back pressure under braking conditions the parts will extend. A weak actuator flange could move like a diaphragm.Under these cyclic stress conditions cracks will emerge and increase until the stress is released. This leads to distorsion of the turbine housing and also of the vane ring assembly. In consequence of this either the vanes will stick or, if the actuator force (> 1000 N) can keep them moving against the resistance force, all parts of the whole mechanism will be rapidly worn out.The distorsion of turbine housing and actuator flange will also lead to high leakage and hence braking power will decline.3.2 Technical SolutionsBased on a measured temperature field a FEA analysis was done. The result showed that the expansion from the tongue area of the turbine housing to the opposite volute area was about 2.3 mm larger than in the perpendicular direction! Similar effects in axial direction could be shown at the tongue area compared to the free volute. The bending of the actuator flange from inner to outer diameter could be more than 1 mm.The design of the turbine housing was optimized by reducing the material concentration in the tongue / inlet flange area and decoupling it from the volute. Radial arranged ribs stiffened the actuator flange. The simulation for the final design showed a maximal difference in expansion of 0.5 (0.8) mm.Both parts have to be treated with a special annealed heat process to eliminate residual stress of the casting.An additional option is the use of chromium – nickel based alloy.Thermal expansion X + 2 mmThermal expansion X mm Figure 3a: Main expansion directions Cracks after thermal shock testFigure 3b: Optimized design of turbine housing and actuator flange3.3 Validation Programs and ResultsTo validate the improvement an accelerated durability test was defined. Two units were arranged as a tandem on a gas stand. A swing flap produced a cyclic load of 700 °C hot gas and 20 °C cold air alternately to both VTGs.The result was outstanding: While the first design after only 150 hours testing had cracks in several areas up to 30 mm length and still growing, the final design had no cracks in the critical areas after 500 hours testing.4. VANE RING ASSEMBLY4.1 Technical ChallengesThe vane ring assembly is the central component of the VTG. It has to create good performance both under fired and under braking conditions. The vanes are directly confronted with the exhaust flow, so they see the highest temperatures and the highest pressures including pulsation. Under these conditions the following critical items have to be considered:• Fret on the axle of the vanes due to static gas forces• Wear on the axle of the vanes due to dynamic gas forces• High-frequent vibration-friction-wear caused by fast direction changes of the force in torque free vane positionsFor the design of the vane will also basically generate the forces to all the other parts of the mechanism, it has to be considered very exactly.4.2 Technical SolutionsThe static forces are not a real problem, as long as the vane is freely movable in the vane rings and there is no enforced contact. This can be achieved if the positions of holes for the two axles of each vane are concentric. For this the inner and outer vane ring are machined in one operation.The dynamic forces, especially for the first two or three vane downstream the tongue, are very critical. Combined with very hard sedimentations of adhesives of the fuel in the bore of the vane ring, abrasive wear can occur. There are two ways to improve this situation:• Change the design of the tongue in such a way that the exiting forces are lower. This can be achieved by changing the distance to the vanes, the flow angle to the vanes or by distributing the forces in circumferential direction.• Change the combination of material to better tribological features. So a material, which creates an oxide film on the surface will reduce sedimentations, and a partner with sulphur as a solid lubricant gives an additional improvement.Both measures can be combined.High-frequency vibration-friction-wear cannot be solved by tribological improvements. This will only decelerate the wear. To avoid wear, the high-frequency vibration has to be eliminated. This can be solved by a design where in every vane position the torque of the flow forces operates in one direction. For the fail-safe mode requires an open vane position, the pivot axle has to be positioned in front of the balance axle.4.3 Validation Programs and ResultsIn this case the validation had to be done on the engine under real (braking) conditions. A high cyclic program with a share of more than 30 % braking was run for 750 hours. The first design showed in this test wear of up to 1 mm on the axis of the vanes. The results were satisfying with a unit, which included all above mentioned measures and a vane design shown in figure 4b. The position of the pivot axle made sure that there is no change in force direction, but the actuating forces got very high. Figure 4c shows the design that gives the best compromise between direction and magnitude of the force.Overlapping of next vaneL1 = L2 L1 >> L2L1 > L24a 4b 4cFigure 4a – 4c: Comparison of vane designs5. ADJUSTMENT RING ASSEMBLY5.1 Technical ChallengesThe adjustment ring assembly is the link between the vane ring assembly and the adjustment shaft. It has to make sure that the actuating forces are transmitted with low hysteresis and no wear and that the vanes all have exactly the same position especially in nearly closed positions for braking mode.This results in two main challenges:• To achieve low hysteresis and no wear the adjustment ring has to be as weight reduced as possible.• To ensure exact vane positions the ring has to keep its flat and circular shape even after welding of the pins for the sliding blocks.5.2 Technical SolutionsIt is clear that both challenges can only be solved together. It is easy to reduce the area of the full ring disc to the minimum of the required contact areas. Also the manufacturability is no real problem.But the welding of the pivot pins is tricky. Since hot spots cause distorsion, a low energy welding process is required. Even with electron beam welding the required flatness and roundness is not easily achievable. Only in a very close collaboration with the manufacturer of the ring and the welding company the process and the design can be advanced to the target.5.3 Validation Programs and ResultsThe mass optimized adjustment ring design is shown in figure 5. The weight reduction was about 40 % compared to the basic full disc version.With an electron beam process which includes compensation spots on the opposite side of the welding of the large sliding block, flatness and roundness of < 0.35 mm is achievable.In the validation process the adjustment ring assembly passed the same engine test as the vane ring assembly successfully.Shape of full discFigure 5: Optimized design of adjustment ring6. ACTUATOR6.1 Technical ChallengesThe actuator of a VTG has to fulfil a much more demanding specification compared to wastegated turbochargers in commercial diesel:Feature VTG Wastegate • actuation stroke 24 mm 4-5 mm • control pressures 6,5 bar 3 bar • spring forces 2000 N 450 N • full strokes 1 million 20.000 • part strokes 8 million 700.0001234567City cycleCountry roadHighway10% City cycle 20% Country road 70% HighwayN u m b e r o f s t r o k e s [m i l l i o n s ]Figure 6: Measured actuator cycle for heavy-duty truck6.2 Technical SolutionsThe higher pressure and the higher spring forces require a more solid design. This is achievable with a similar design as for wastegate but with a thicker metal sheet for the cover.The real challenge is the lifetime of the diaphragm with strokes of up to 24 mm. The production process with the fabric on top of the silicon (lay up) as used for the standard wastegates gives only a lifetime of 500.000 up to 800.000 full strokes. To increase the lifetime by a factor of about 10, a totally new manufacturing process for the diaphragm is required. The cloth diaphragm consists of a special fabric, which is positioned in the middle of the elastomer, which allows homogeneous stress behaviour. Pleats, which are the basic reasons for failures of the diaphragm, are postponed fundamentally.Hence life is increased! 6.3 Validation Programs and ResultsTo validate the improvement an accelerated durability test was defined. Several complete actuators were arranged in a test rig and operated under the following conditions:• test pressure 0 – 7 bar• test frequency 0.8 Hz• test temperature 120 °C• actuation stroke 24 mmA lifetime of minimum 4.5 million full strokes was achieved. A conversion to a mixed cycle as shown in figure 6 gave a safety factor of 1.3. An option is a linear operating actuator, which gives additional 20% of lifetime.7. PROSPECTS OF THE MARKET/FUTURE DEVELOPMENT STEPSThe above described development features are part of a comprehensive validation program which exceeded 15.000 hours of gas stand and engine testing and 2.000.000 km on trucks. Currently more than 300 trucks increase field experience day by day. A series application will be launched in Europe early in 2002; SOP for a matching with EGR that fulfils EPA 02 in the US will be October 2002.Concerning the prospects of the market for the VTG in the view of the upcoming emission limits Euro 4 and Euro 5, the following statements can be made:• None of the engine manufacturers knows today which will be the main route to fulfil these legislations: EGR, SCR or PM-filter• All of these possibilities could be well supported by VTGEGR: VTG generates sufficient back pressure to drive EGR at full loadSCR: VTG enables conversion at part load by increasing exhausttemperaturePM filter: VTG enables regeneration of filter by increasing exhaust temperature • The drivability will be improved fundamentally in all casesThis means that the VTG is an interesting tool also for future applications. Now the durability issues have been solved, to increase its attraction future development steps will focus on cost reduction and efficiency increases. Cost reduction items are simplified designs and new production processes as for example metal injection moulding (MIM). Efficiency can be increased primary by reduction of the losses caused by all the clearances of the mechanism and especially of the vanes. Besides a reduced BSFC, an increased braking performance at medium engine speed would allow a replacement of existing large and permanent operatingretarders by smaller, discontinuous working units which would be a huge cost reduction of the system.8. SUMMARY• VTG for Commercial Diesel is now a well developed charging system• Durability under braking conditions has been validated• VTG is also an interesting tool to fulfil the next emission legislation steps• There is a big potential in further development steps to increase the benefit to the customerLiterature:[1] Engels, B.; Hemer, H.-J.Turbolader mit verstellbarer Turbinengeometrie für Nutzfahrzeugmotoren6. Aufladetechnische Konferenz, Dresden, 1. – 2. Oktober 1997[2] Oelschlegel, H.; Schäfer, A.Exhaust Aftertreatment Strategies for Commercial Vehicle Diesel Engines toFulfill EURO 4/5 Exhaust Emissions Limits10. Aachener Kolloquium Fahrzeug- und Motorentechnik 2001B.[3] Engels,Titanium Compressor Wheels for Vehicle Applications7th Intern. Conference on Turbochargers and Turbocharging, 14 -15 May 200210BorgWarner Turbo SystemsWorlwide Headquarters GmbHMarnheimer Strasse 8867292 Kirchheimbolanden / GermanyPhone: ++49 (0)6352 75 33 0Fax: ++49 (0)6352 75 33 993K-Warner Turbosystems GmbHMarnheimer Strasse 85/8767292 Kirchheimbolanden / GermanyPhone: ++49 (0)6352 403 0Fax: ++49 (0)6352 403 1866BorgWarner Turbo Systems Ltd.Euroway Industrial EstateBradford BD4 6SEWest Yorkshire / UKPhone: ++44 1274 684 915Fax: ++44 1274 689 671BorgWarner Turbo SystemsPO Box 15075Asheville, NC 28813/USAPhone: 001 828 684 4000Fax: 001 828 684 4114BorgWarner Automotive Brasil Ltda.Estrada da Rhodia Km 15P.O. Box 654013084-970 Campinas-SP / BrasilPhone: ++55 19 3787 5700Fax: ++55 19 3787 5701Hitachi Warner Turbo Systems Ltd.3085-5 Higashi Ishikawa Saikouchi, Hitachinaka-shi Ibaraki-ken312-0052, JapanPhone: +81 (0) 29-276-9388Fax: +81 (0) 29-276-9397。
国内外绿色建筑评价体系对比分析
Hans Journal of Civil Engineering 土木工程, 2023, 12(3), 633-645 Published Online May 2023 in Hans. https:///journal/hjce https:///10.12677/hjce.2023.125071国内外绿色建筑评价体系对比分析陈泓洁西京学院土木工程学院，陕西 西安收稿日期：2023年4月25日；录用日期：2023年5月15日；发布日期：2023年5月30日摘要目前节能减排“十三五”规划中也对绿色建筑相关内容做出了要求，并且“碳达峰”和“碳中和”也被写入了政府工作报告，加快推广与发展绿色建筑，不仅减少了建筑领域碳排放，还是我国早日实现碳达峰目标的重要途径。
所以本文介绍了国内外绿色建筑评价体系的特点和关键体系新旧版的对比，了解了各国各体系的以后发展的方向，并从对各国体系制定者、最早颁布时间、评价范围、组织类型，评价对象、评价指标、评价内容、评价方法、评级分级方面将各个评价体系进行深入剖析，最后给出对我国绿色建筑评估体系的启示，为我国绿色建筑体系发展与更新提供参考。
关键词绿色建筑，评价体系，对比分析，可持续发展Comparative Analysis of Domestic and Foreign Green Building Evaluation SystemsHongjie ChenCollege of Civil Engineering, Xijing University, Xi‘an ShaanxiReceived: Apr. 25th , 2023; accepted: May 15th , 2023; published: May 30th, 2023AbstractAt present, the “13th Five-Year Plan” of energy saving and emission reduction has also made re-quirements for green buildings, and “carbon peak” and “carbon neutrality” have been written into the government work report, accelerating the promotion and development of green buildings not only reduce carbon emissions in the construction field, but also are an important way for China to陈泓洁achieve the goal of carbon peak as soon as possible. Therefore, this paper introduces the characte-ristics of domestic and foreign green building evaluation systems and the comparison of the old and new versions of the key systems, understands the future development direction of each sys-tem in each country, and makes an in-depth analysis of each evaluation system from the perspec-tive of the system maker, the earliest promulgation time, the evaluation scope, the organization type, the evaluation object, the evaluation index, the evaluation content, the evaluation method, the rating classification. Finally, the inspiration for China’s green building evaluation system is given to provide a reference for the development and update of China’s green building system.KeywordsGreen Building, Evaluation System, Comparative Analysis, Sustainable Development Array Copyright © 2023 by author(s) and Hans Publishers Inc.This work is licensed under the Creative Commons Attribution International License (CC BY 4.0)./licenses/by/4.0/1. 引言二十世纪末，绿色建筑已被许多国家接受为实施可持续发展战略的任务之一，环境保护和能源消耗问题已经引起了社会的重视。
DeepWind 5 MW baseline design
E nergy Procedia 24 ( 2012 )27 – 351876-6102 © 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of SINTEF Energi AS.doi: 10.1016/j.egypro.2012.06.083DeepWind, 19-20 January 2012, Trondheim, Norway1st DeepWind 5 MW baseline designUwe S. Paulsen a , Luca Vita a ,Helge A. Madsen a ,Jesper Hattel b ,Ewen Ritchie c ,Krisztina M. Leban c ,Petter A. Berthelsen d , Stefan Carstensen eaRisø National Laboratory for Sustainable EnergyRisø DTU,P.O.Box 49,Dk-4000 Roskilde,Denamarkb Technical University of Denmark DTU MEK,NilsKoppels AlléB404, Dk-2800 Lyngby, Denmarkc Ålborg University Department of Energy Technology, Pontoppidanstræde 101, 67, Dk-9220 Ålborg, Denmarkd Marintek, P.O.Box 4125 Valentinlyst, NO-7450 Trondheim, Norwaye DHI, Agern Allé 5 DK-2970 Hørsholm, Denmark AbstractThe first 5MW baseline design of the DeepWind concept is presented for a Darrieus type floating wind turbine system for water depths of more than 150 m. This design will be used as design reference to test the next technological improvements of sub-component level,being based as much as possible on existing technology.The iterative design process involves all sub-components and the potential constraints, and the most important dependencies are highlighted and the selected design presented. The blades are designed with constraints to minimize the gravitational loads and to be produced in a controlled pultrusion process. The floating platform is a slender cylindrical structure (i.e. spar buoy) rotating along with the rotor. The stability of the platform is achieved by adding counter weight at the bottom of the structure. During operations, the rotor is tilted and acts as a gyro, describing an elliptical trajectory on the water plane. The generator is placed at the bottom of the platform and uses 5MW direct drive technology.The conceptual design is evaluated with numerical simulations in the time domain using the aero-elastic code HAWC2. In order to investigate the concept, a double-disc blade element momentum (BEM) code for VAWTs has been included in the numerical solver through a dll.The analysis of the design is carried out in two different steps:1) to estimate natural frequencies of the platform in order to avoid major resonance problems,2)to evaluate the baseline concept for certain load cases. A site has been chosen for the floating turbine off Norway as representative for external conditions. The structure is verified according to an ultimate strength analysis, including loads from wind, waves and currents. The stability of the platform is investigated, considering the displacements of the spar buoy and the maximum inclination angle, which is kept lower than 15 degrees.©2011Published by Elsevier Ltd.Keywords: vertical axis; structural design; pultrusion; floating offshore wind turbine;submerged generator;direct drive wind generator Available online at © 2012 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of SINTEF Energi AS.28U we S. Paulsen et al. / E nergy Procedia 24 ( 2012 )27 – 35 Figure 1:Constraints in developing baseline design[3]U we S. Paulsen et al. / E nergy Procedia 24 ( 2012 )27 – 35 29 1.2.Environmental loadsThe HAWC2 simulations take into account the important aero-elastic loads on the wind turbine andthe hydrodynamic loads due to the rotation of the platform in the water,i.e. Magnus effect, in-line forcesand friction torque. The estimation of these loads is based on results from literature [2, 5,6,7]. CFD calculations and physical model test with a rotating cylinder in combined waves and current are on-goingat DHI to verify the hydrodynamic loads and support their implementation in the HAWC2 model. Boththe numerical simulations and laboratory tests forecast a low friction loss, and a major Magnus force in combined waves and currents associated with the rotation.1.3.1st Design assumptionsThe post-stall as well as the effects by the wind turbulence are known to increase rotor loads in the dynamic stall region. The concept is described in 6-DOF:{(Pitch, Roll, Yaw), (Surge, Sway, Heave)}[1, 2]. The following assumptions are made in the first iteration design:x Atmospheric turbulence effects are not consideredx Dynamic stall is not includedx Evaluation of loads are conducted on a configuration with a limited DOF, i.e.Pitch, Roll,Yaw2.Rotor and blades design2.1.Site conditionsThe DeepWind design is site dependent [2, 3]. The H yWind test site has been selected as the representative site for the evaluation of DeepWind.The position is shown in Figure 2.For this site the environmental conditions are described by the NORSOK standard[8]as:Maximum 100 year tidal surface current in the order of 0.2m/s; wind induced (surface) current velocity of up to 0.5m/s;signify-Figure 2Approximate position of the DeepWind turbine evaluation site -here indicated with a red mark,from a map of the domainfor DHI’s North Sea wave hindcast model.30U we S. Paulsen et al. / E nergy Procedia 24 ( 2012 )27 – 35U we S. Paulsen et al. / E nergy Procedia 24 ( 2012 )27 – 35 31A number of changes are planned for the next iteration loop: a)a lower value of V improves the rotor stall characteristic and moves the rated conditions towards higher values of rotational speed and lower wind speed which results in a less costly generator, b)a thinner airfoil could improve the rotor stall characteristic. A VAWT reaches the power peak at a higher wind speed as compared to a HAWT and in order to provide a more reasonable comparison of the wind turbine concepts it is decided with DeepWindto obtain the same AEP of the 5 MW reference HAWT wind turbine,i.e.c)a rotor design with higher rated power is necessary. As in Figure 1 these changes affect the subcomponent level as well.2.2.Blade designThe use of pultrusion technology for VAWT blade manufacture is limited to constant chord over length; it provides a surplus in terms of low manufacturing cost but at the expense of increased material consumption to compensate for structural strength of relatively thin profiles. This has shown the necessityto design blades with structured ‘stiffeners’ which can avoid heavy blade design. The present blade design is not shape optimized to account for best rigidity at lowest blade weight in the first iteration of the process. Gravity and centrifugal load combinations are limiting design parameters and have impacts onthe rotor shape. A suitable alternative is to change the operating condition by changing the tip speed orrpm slightly-which changes the shape of the blade,and the loads as shown in Figure 4.The suggested design changes of the overall rotor will result in a lighter blade design. In particular it is structurally convenient to use thicker airfoils at positions which are nearer to the tower.Figure 4: Left: Two different blade shapes according to two different operational conditions. Right: Loads corresponding to the two different rotor shapes[3].The current blade span measures 189 m and weighs154 metric tons,which at this stage is too heavy with negative impacts on the systems design. Alternative blade designs such as using piecewise constant profiles, and thick profiles are explored at the moment.A compromise in the design includes a possible increase in the rated rotational speed,or a variation of the blade properties along the blade with lighterblade material density.32U we S. Paulsen et al. / E nergy Procedia 24 ( 2012 )27 – 353.Floating platformThe floating platform for the DeepWind concept is based on the spar technology. The spar concept has shown to be a promising solution for floating offshore wind turbines due to its favorable motion [9].The spar is a deep draught vertical cylinder with buoyancy chambers at the upper part and a heavier section at the lower end for stabilization. The upper part of the spar buoy is narrowed with a tapered section such that a small diameter is obtained in the wave zone, in order to limit wave loads and to connect the platform to the rotor tower. Vertical wave forces are minimized due to the deep draught of the spar buoy such that vertical motions are rather small. The low center of gravity provides large righting moment ensuring that the floater stays upright with low roll and pitch motion. The selection of the spar hull shape and size depends on functional requirements,and the following basic design requirements are considered:x Natural periods in heave and pitch/roll should be larger than the dominating wave periods(i.e. 5s-25 s)to avoid resonant motion responsex Sufficient buoyancy to carry specified payload and weight of the mooring systemx Sufficient vertical stiffness for variable vertical loadx Sufficient stiffness in roll and pitch to avoid excessive heeling of the platform due to environmental loadsx Acceleration should be limited to avoid damage to machinery componentsThe baseline design is summarized in Table 3.Table 3:Platform dimensionsGeometry of the platformTotal length (H P=H1+H2+H3)[m]108Depth of the slender part(H1)[m]5Radius of the slender part (R T)[m] 3.15Thickness of the slender part [m]0.02Length of the tapered part (H2)[m]10Length of the bottom part (H3)[m]93Maximum radius of the platform(R P)[m] 4.15Thickness of the bottom part[m]0.05The most relevant stiffness parameters of the platform were calculated in [3]to verify the design for fulfillment of the design requirements.Reduction of the top weight due to a re-design of the blades will alter the shape and size of the spar hull. A preliminary study indicates that reducing the blade mass and lowering the blades' mass centre allows for reducing the diameter and draught of the spar buoy. Further optimization of the spar design is therefore considered. In this context, optimization is the same as minimizing the material cost while satisfying the design requirements. The design iterations will also include finding a feasible mooring system that can withstand the large torque from the rotating wind turbine.U we S. Paulsen et al. / E nergy Procedia 24 ( 2012 )27 – 35 33 4.Subsea generator technology4.1.Generator State of the Art and Design IssuesA state of the art investigation was conducted to determine possible solutions for the generator. Typesof direct drive generators on the market were found and a comparison was made between the types of generator used in and proposed for wind power applications. Types of direct drive generators on the market are presented in Table 4:Table 4:Large Direct Drive Wind Turbines [10,11]Generator Type Power/Speed ManufacturerEESG 4.5 MW/ 13 rpm EnerconPMSG 3.5 MW/ 19 rpm ScanwindPMSG 2.5 MW/ 14.5(16) rpm VensysPMSG 2 MW/ 24 rpm MitsubishiPMSG 2 MW/ 18.5rpm STX WindpowerPMSG 2 MW/ 15.8 rpm EWT (Energya Wind Technologies)PMSG 2 MW/ 19 rpm JSW (Japan Steel Works)EESG 1.65 MW/ 20 rpm MT TorresPMSG 1.5 MW/ 23 rpm LeitwindPMSG 1.5MW/ 19 rpm GoldwindPMSG 1.5(2) MW/ 18(23) rpm ZephyrosPMSG0.75 MW/ 25 rpm Jeumont(not available)Siemens Wind Energy launched a 6MW direct drive SWT-6.0prototype in November 2010. The turbine is designed for the harsh offshore conditions. The first prototype was installed in May 2011 in Denmark. Offshore sites targeted for 2012-2013 include Denmark, UK, the Netherlands and Germany.Tests are still being carried out on the installed prototypes [12].Because of the special sub-sea ambient conditions, it is important to identify the best candidates for the DeepWind direct drive generator. This requires an assessment of the suitable candidates for the proposed application.During the project the following generator types were considered:1.SCIG-Squirrel Cage Induction Generator(Radial Flux RF)2.DFIG –Doubly Fed Induction Generator(Radial Flux RF)3.EESG -Electrically Excited Synchronous Generator(Radial Flux RF)4.PMSG -PM Synchronous Generator(Radial Flux RF)5.TFPM -Transverse Flux PM Generator6.AFPM –Axial Flux PM GeneratorA SWOT analysis was performed to narrow down the list of candidates.The main selection criteriawere related to the efficiency, torque/weight ratio, mass of active and inactive material, fault ride through capability, ease of manufacturing, existing turbines on the market. From this assessment and analysis itcan be concluded, that the candidates worth considering for the DeepWind direct drive applications are: Synchronous PM(PMSG)Synchronous Electrically Excited(EESG)Transverse Flux PM (TFPMG)34U we S. Paulsen et al. / E nergy Procedia 24 ( 2012 )27 – 35A design tool for each machine type tailored to direct drive specifications will be used to determinethe suitability of each generator type. The decision for proceeding with these machine types is related to the cost of permanent magnets and the particular optimization potential for each generator.4.2.DeepWind Generator Design approachThe analytic design algorithm for the machines was implemented in code language. Usual design rules used for power station generators were applied. It is anticipated that these will be adjusted to suit the subsea ambient conditions. The output of the analytic design will include the geometrical dimensions of the machine, mass of active and inactive materials and evaluation of losses. The geometrical dimensions obtained will be used as input for a finite element model to analyze and optimize the magnetic field distribution in the machine. For a given output, the diameter of the generator may be expected to be inversely proportional to the speed. As the direct drive turbine implies an extremely slow speed (see Table 4), the number of poles of the generator will increase. This means not only that the diameter of the machine will increase, but that the leakage field will also increase. This is not desired as it will reduce the efficiency of the generator. By observing the magnetic field in a particular machine design, suitable optimization measures can be taken in order to maximize the useful magnetic field and minimize the unwanted field effects.A thermal model of each candidate generator type will be constructed replicating the subsea ambient conditions and enabling the establishment of corresponding new appropriate design rules. This is because of the relatively unknown cooling conditions for the generator caused by the sub-sea environment and affected by the constructional details and enclosure. An optimization tool will be designed to improve the performance of the generator. By careful selection of the active materials and varying the geometry of the proposed design a new optimized machine design will be obtained. The output of the generator will be fed to a power electronic converter for conversion to voltage levels suitable for transmission to the local electricity utility grid. This will be a multi kilovolt connection, so a three level converter is anticipated. Control of the power flow will be by control of the shaft speed of the DeepWind turbine.4.3.First Iteration Dimensions of the 5 MW Direct Drive GeneratorThe first iteration of the 5 MW shaft input generator, based on the estimated rated speed of 5.26 rpm and the rated torque of 9.1MNm was for a 400 pole 17.53 Hz design with a pole pitch of around 7.85cm.This corresponds to an air-gap diameter of around 10 m outer diameter of around 10.5 m, with a core length of around 1.4 m. This will give a total mass of Copper, Iron and permanent magnet materials of around 90 metric tons. The dimensions fit very well with the estimated outer diameter of the platform which is 8.3 m, see Table 3, and will enable a reasonable construction.5.Design evaluationThe design was evaluated with the aero-elastic code HAWC2, in the configuration with 3DOF for the platform under conditions of the sea states[3]. The direction of the waves and the currents, with respect to the wind, was changed in order to evaluate the different loads from different combinations of wind, wave and current direction.Regarding the platform stability,the large inertia of the rotor affects the pitch and roll mode towards a large natural period. The simulations show a rotor inclination at the tower bottom less than 12ºwhen in combinations of wind and current relative to wind direction (waves -90ºand current co-parallel with wind directions, waves co-parallel and current -45º relative to wind directions)and an inclination less than6º in still water.The tower section at sea water level displaces for the most criticalU we S. Paulsen et al. / E nergy Procedia 24 ( 2012 )27 – 35 35 sea state with around 12 m along the wind direction and 12.5m to each side, compared to still water condition with 10.5m and 0.75m, respectively.The maximum loads were recorded at the point on the tower at the water level, and they occur at the most critical sea states (larger values of the wave height), while the mean values are strongly dependenton the currents direction[3].For the ultimate strength of the tower, a safety factor of 2 is used for maximum loads and 4 on mean loads.6.ConclusionsA 1st iteration conceptual 5 MW DeepWind baseline design for a Darrieus type floating wind turbine system with direct drive generator technology, for water depths of more than 150 m was carried out witha design evaluation of the concept. This design will be used as design reference to test the next technological improvements of sub-component level, being based as much as possible on existing technology. The results from the evaluation have shown that different issues in the design space are stillnot optimal and have to be iterated accordingly.AcknowledgementsThe work is a result of the contributions within the DeepWind project which is supported by the EuropeanCommission, Grant 256769 FP7 Energy 2010-Future emerging technologies, and by the DeepWind beneficiaries:DTU(DK), AAU(DK), TUDELFT(NL), TUTRENTO(I), D I(DK), SINTEF(N),MARINTEK(N), MARIN(NL), NREL(USA), STATOIL(N), VESTAS(DK) and NENUPHAR(F). References[1]Vita L, Paulsen US, Pedersen TF, Madsen HA, Rasmussen F A Novel Floating Offshore Windturbine Concept in Proceedingsof the European Wind Energy Conference (EWEC),Marseille, France,2009.[2]Vita L,Zhale F, Paulsen US Pedersen TF, Madsen HA, Rasmussen F. Novel Concept For Floating Offshore Wind Turbines:Concept Description And Investigation Of Lift, Drag And Friction Acting On The Rotating Foundation in Proceedings of the ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering, June 6 Shanghai 2010 OMAE2010-20357.[3]Vita L Offshore floating vertical axis wind turbines with rotating platform Risø DTU, Roskilde, Denmark, PhD dissertationPhD 80, 2011.[4]Jonkman J, Butterfield S, Musial W, Scott G Definition of a 5-MW reference wind turbine for offshore system developmentNational Renewable Energy Laboratory, Golden, Colorado (US), Technical Report NREL/TP-500-38060, 2009.[5]Hoerner, SF,Borst HV Fluid-Dynamic Lift. Bricktown, NJ: Hoerner Fluid Dynamics, 1975.[6]Theodorse T, Kegier A Experiments on drag of revolving disks, cylinders, and streamline rods at high speeds, NationalAdvisory Committee for Aeronautics, Report no. 793.1945[7]Sumer BM, Fredsøe J Hydrodynamics around cylindrical structures, World Scientific, Advanced Series on Coastal Engineering–Volume 12. 1997[8]Norsok standard N-003 Ed.2 Actions And Action Effects2007.[9]H enderson AR,Witcher D, Floating Offshore Wind Energy -A Review of the Current Status and an Assessment of theProspects WIND ENGINEERING VOLUME 34, NO. 1, 2010 PP 01–16[10]Bang D, Polinder H, Shrestha G, Ferreira JA Review of Generator Systems for Direct-Drive Wind Turbines[11]Bang D Design of Transverse Flux PM M achines for Large Direct-Drive Wind Turbines.Busan,Korea:Master ofEngineering, Pukyong National University, 2010. ISBN 978-90-5335-336-3[12]/press/en/pressrelease/?press=/en/pressrelease/2011/wind-power/ewp201111014.htm.Site accessedDecember 18 2011.。
电化学预处理玻碳电极示差脉冲伏安法测定水中痕量铅_于春梅
电化学预处理玻碳电极示差脉冲伏安法 测定水中痕量铅
于春梅 , 顾海鹰 *
( 南通大学 公共卫生学院 , 南通 226007) 摘 要:
将玻碳电极在 pH 4. 0 乙酸盐缓冲溶液中, 于电位 + 1. 8 V( vs . SCE) 处阳极氧化 , 然后
在- 0. 8~ + 1. 0 V 电位范围内循环扫描, 进行预处理。 研究了铅离子在预处理玻碳电极上的电化 学行为, 结果表明: 与未修饰的电极相比, Pb 2+ 在该修饰电极上有一对氧化还原峰 , 峰电位分别为 - 0. 57 V 和 - 0. 68 V( vs . SCE) , 且峰电流大大提高 。据此提出了示差脉冲伏安法测定 Pb 2+ 的方 法。 在优化的试验条件下, 氧化峰电流与 P b2+ 的浓度在 3. 2 @ 10- 7 ~ 4. 2 @ 10- 5 m ol # L - 1 范围内 呈线性关系 。检出限 ( 3S / N ) 为 3. 2 @ 10 mo l # L 。 应用该预处理电极测定水样中微量铅 , 加标 回收率在 93. 8% ~ 104. 7% 之间 , 相对标准偏差 ( n= 6) 在 3. 1% ~ 4. 3% 之间。
- 1
图1 Fi g. 1
玻碳电极 ( 1) 和预处理玻碳电极 ( 2) 的循环伏安图
Cycl ic vol tammograms of G CE ( 1) and pret reat ed G CE ( 2)
pH 7. 0 磷酸 盐缓 冲溶 液 ( PBS) : 0. 10 mol # , 由磷酸氢二钠和磷酸二氢钠混合配制得到。 乙酸 - 乙酸钠缓冲 溶液: 由 0. 2 mo l # L- 1 乙 酸
YU Chun -mei, GU Hai ying
热处理工艺常用英文词汇
X线结晶分析法 X – ray crystal analyics method奥氏体 Austenite奥氏体碳钢 Austenite Carbon Steel奥氏铁孻回火 Austempering半静钢 Semi-killed steel包晶反应 Peritectic Reaction包晶合金 Peritectic Alloy包晶温度 Peritectic Temperature薄卷片及薄片（0.3至2.9mm厚之片）机械性能 Mechanical Properties of Thin Stainless Steel（Thickness from 0.3mm to 2.9mm）– strip/sheet杯突测试（厚度： 0.4公厘至1.6公厘，准确至0.1公厘 3个试片平均数） Erichsen test （Thickness： 0.4mm to 1.6mm， figure round up to 0.1mm）贝氏体钢片 Bainite Steel Strip比电阻 Specific resistivity & specific resistance比较抗磁体、顺磁体及铁磁体 Comparison of Diamagnetism， Paramagnetic & Ferromagnetism比热 Specific Heat比重 Specific gravity & specific density边缘处理 Edge Finish扁线、半圆线及异形线 Flat Wire， Half Round Wire， Shaped WirePrecision Shaped Fine Wire扁线公差 Flat Wire Tolerance变态点 Transformation Point表面保护胶纸 Surface protection film表面处理 Surface finish表面处理 Surface Treatment不破坏检验 Non – destructive inspections不锈钢 Stainless Steel不锈钢–种类，工业标准，化学成份，特点及主要用途 Stainless Steel – Type， Industrial Standard，Chemical Composition， Characteristic & end usage of the most commonly used Stainless Steel 不锈钢薄片用途例 End Usage of Thinner Gauge不锈钢扁线及半圆线常用材料 Commonly used materials for Stainless Flat Wire & Half Round Wire不锈钢箔、卷片、片及板之厚度分类 Classification of Foil， Strip， Sheet & Plate by Thickness不锈钢材及耐热钢材标准对照表 StainlessHeat-Resisting Steels不锈钢的磁性 Magnetic Property & Stainless Steel不锈钢的定义 Definition of Stainless Steel不锈钢基层金属 Stainless Steel as Base Metal不锈钢片、板用途例 Examples of End Usages of Strip， Sheet & Plate不锈钢片材常用代号 Designation of SUS Steel Special Use Stainless不锈钢片机械性能（301， 304， 631， CSP） Mechanical Properties of Spring use Stainless Steel 不锈钢应力退火卷片常用规格名词图解 General Specification of Tension Annealed Stainless Steel Strips 不锈钢之分类，耐腐蚀性及耐热性 Classification， Corrosion Resistant & Heat Resistance of Stainless Steel 材料的加工性能 Drawing abillity插入型固熔体 Interstital solid solution常用尺寸 Commonly Used Size常用的弹簧不锈钢线-编号，特性，表面处理及化学成份 StainlessSpring Wire – National Standard number，Charateristic， Surface finish & Chemical composition常用的镀锌钢片（电解片）的基层金属、用途、日工标准、美材标准及一般厚度 Base metal， application， JIS & ASTM standard，Normal thickness of galvanized steel sheet长度公差 Length Tolerance超耐热钢 Special Heat Resistance Steel超声波探伤法 Ultrasonic inspection冲击测试 Impact Test冲剪 Drawing & stamping初释纯铁体 Pro-entectoid ferrite处理及表面状况 Finish & Surface纯铁体 Ferrite磁场 Magnetic Field磁畴 Magnetic domain磁粉探伤法 Magnetic particle inspection磁化率 Magnetic Susceptibility （Xm）磁矩 magnetic moment磁力 Magnetic磁力 Magnetic Force磁偶极子 Dipole磁性 Magnetisum磁性变态 Magnetic Transformation磁性变态点 Magnetic Transformation磁性感应 Magnetic Induction粗珠光体 Coarse pearlite淬火 Quenching淬火及回火状态 Hardened & Tempered Strip/ Precision – Quenched Steel Strip淬火剂 Quenching Media单相金属 Single Phase Metal单相轧压镀锡薄铁片（白铁皮/马口铁） Single-Reduced Tinplate弹簧不锈钢线，线径及拉力列表 Stainless Spring Steel， Wire diameterTensile strength of Spring Wire 弹簧用碳钢片 CarbonSteel Strip For Spring Use弹簧用碳钢片材之边缘处理 Edge Finished弹性限度、阳氏弹性系数及屈服点 elastic limit， Yeung''s module of elasticity to yield point倒后擦发条 Pull Back Power Spring导热度 Heat conductivity低碳钢或铁基层金属 Iron & Low Carbon as Base Metal低碳马氏体不锈钢 Low Carbon Martensite Stainless Steel低温脆性 Cold brittleness低温退火 Low Temperature Annealing第二潜变期 Secondary Creep第三潜变期 Tertiary Creep第壹潜变期 Primary Creep点焊 Spot welding电镀金属钢片 Plate Metal Strip电镀金属捆片的优点 Advantage of Using Plate Metal Strip电镀锌（电解）钢片 Electro-galvanized Steel Sheet电镀锌钢片的焊接 Welding of Electro-galvanized steel sheet电镀锌钢片或电解钢片 Electro-galvanized Steel Sheet/Electrolytic Zinc Coated Steel Sheet电解/电镀锌大大增强钢片的防锈能力 Galvanic Action improving Weather & Corrosion Resistance of the Base Steel Sheet电解冷轧钢片厚度公差 Thickness Tolerance of Electrolytic Cold-rolled sheet电炉 Electric furnace电器及家电外壳用镀层冷辘 [低碳] 钢片 Coated （Low Carbon） Steel Sheets for Casing，Electricals & Home Appliances电器用的硅 [硅] 钢片之分类 Classification of Silicon Steel Sheet for Electrical Use电器用钢片的绝缘涂层 Performance of Surface Insulation of Electrical Steel Sheets电器用钢片用家需自行应力退火原因 Annealing of the Electrical Steel Sheet电器用硅 [硅] 钢片 Electrical Steel Sheet电阻焊 Resistance Welding定型发条 Constant Torque Spring定型发条的形状及翻动过程 ShapeSpring Back of Constant Torque Spring定型发条及上炼发条的驱动力 Spring Force of Constant Torque SpringWing-up Spring定型发条驱动力公式及代号 The FormulaSymbol of Constant Torque Spring镀层质量标记 Markings & Designations of Differential Coatings镀铬 Chrome Plated镀黄铜 Brass Plated镀铝（硅）钢片–美材试标准（ASTM A-463-77）35.7 JIS G3314镀热浸铝片的机械性能 Mechanical Properties of JIS G 3314 Hot-Dip Aluminum-coated SheetsCoils镀铝（硅）钢片–日工标准（JIS G3314） Hot-aluminum-coated sheetscoils to JIS G 3314镀铝（硅）钢片及其它种类钢片的抗腐蚀性能比较 Comparsion of various resistance of aluminized steel & other kinds of steel镀铝（硅）钢片生产流程 Aluminum Steel Sheet， Production Flow Chart镀铝硅钢片 Aluminized Silicon Alloy Steel Sheet镀铝硅合金钢片的特色 Feature of Aluminized Silicon Alloy Steel Sheet镀镍 Nickel Plated镀锡薄钢片（白铁皮/马日铁）制造过程 Production Process of Electrolytic Tinplate镀锡薄铁片（白铁皮/马口铁）（日工标准 JIS G3303）镀锡薄铁片的构造 Construction of Electrolytic Tinplate锻造 Fogging断面缩率 Reduction of area发条的分类及材料 Power Spring Strip ClassificationMaterials发条片 Power Spring Strip反铁磁体 Antiferromagnetism方线公差 Square Wire Tolerance防止生锈 Rust Protection放射线探伤法 Radiographic inspection非晶粒取向电力用钢片的电力、磁力、机械性能及夹层系数 Lamination Factors of Electrical， Magnetic & Mechanical Non-Grain Oriented Electrical沸腾钢（未净钢） Rimmed steel分类 Classification负磁力效应 Negative effect钢板 Steel Plate钢板订货需知 Ordering of Steel Plate钢板生产流程 Production Flow Chart钢板用途分类及各国钢板的工业标准包括日工标准及美材试标准 Type of steel Plate & Related JIS， ASTMOther Major Industrial Standards钢材的熔铸、锻造、挤压及延轧 The Casting， Fogging， Extrusion， Rolling & Steel钢的脆性 Brittleness of Steel钢的种类 Type of Steel钢铁的名称 Name of steel钢铁的制造 Manufacturing of Steel钢铁的主要成份 The major element of steel钢铁生产流程 Steel Production Flow Chart钢铁用“碳”之含量来分类 Classification of Steel according to Carbon contents高锰钢铸–日工标准 High manganese steel to JIS standard高碳钢化学成份及用途 High Carbon Tool Steel， Chemical CompositionUsage高碳钢片 High Carbon Steel Strip高碳钢片用途 End Usage of High Carbon Steel Strip高碳钢线枝 High Carbon Steel Wire Rod （to JIS G3506）高温回火 High Temperature Tempering格子常数 Lattice constant铬钢–日工标准 JIS G4104 Chrome steel to JIS G4104铬镍不锈钢及抗热钢弹簧线材–美国材验学会 ASTM A313 –1987 Chromium –Nickel StainlessHeat-resisting Steel Spring Wire – ASTM A313 – 1987铬系耐热钢 Chrome Heat Resistance Steel铬钼钢钢材–日工标准 G4105 62 Chrome Molybdenum steel to JIS G4105各种不锈钢线在不同处理拉力比较表 Tensile Strength of various kinds of Stainless Steel Wire under Different Finish工业标准及规格–铁及非铁金属 Industrial Standard – Ferrous & Non – ferrous Metal公差 Size Tolerance共晶 Eutectic共释变态 Eutectoid Transformation固熔体 Solid solution光辉退火 Bright Annealing光线（低碳钢线），火线（退火低碳钢线），铅水线（镀锌低碳钢线）及制造钉用低碳钢线之代号、公差及备注Ordinary Low Carbon Steel Wire， Annealed Low Carbon Steel Wire， Galvanized low Carbon Steel Wire & Low Carbon Steel Wire for nail manufacturing - classification， Symbol of Grade， ToleranceRemarks.硅含量对电器用的低碳钢片的最大好处 The Advantage of Using Silicon low Carbon Steel滚焊 Seam welding过共晶体 Hyper-ectectic Alloy过共释钢 Hype-eutectoid含硫易车钢 Sulphuric Free Cutting Steel含铅易车钢 Leaded Free Cutting Steel含铁体不锈钢 Ferrite Stainless Steel焊接 Welding焊接合金 SolderingBrazing Alloy焊接能力 Weldability 镀铝钢片的焊接状态（比较冷辘钢片） Tips on welding of Aluminized sheet in comparasion with cold rolled steel strip合金平衡状态 Thermal Equilibrium厚度及阔度公差 Tolerance on Thickness & Width滑动面 Slip Plan化学成份 Chemical Composition化学结合 Chemical bond化学性能 Chemical Properties化学元素 Chemical element黄铜基层金属 Brass as Base Metal回复柔软 Crystal Recovery回火脆性 Temper brittleness回火有低温回火及高温回火 Low & High Temperature Tempering回火状态 Annealed Strip基层金属 Base Metal of Plated Metal Strip机械性能 Mechanical Properites机械性能 Mechanical properties畸变 Distortion级别、电镀方法、镀层质量及常用称号 Grade， Plating type， Designation of Coating Mass & Common Coating Mass级别，代号，扭曲特性及可用之线材直径 Classes， symbols， twisting characteristicapplied Wire Diameters 级别，代号及化学成份 Classification， Symbol of GradeChemical Composition挤压 Extrusion加工方法 Manufacturing Method加工性能 Machinability简介 General交换能量 Positive energy exchange矫顽磁力 Coercive Force金属变态 Transformation金属材料的试验方法 The Method of Metal inspection金属材料的性能及试验 Properties & testing of metal金属的特性 Features of Metal金属的相融、相融温度、晶体反应及合金在共晶合金、固熔孻共晶合金及偏晶反应的比较 Equilibrium Comparision 金属间化物 Intermetallic compound金属结晶格子 Metal space lattice金属捆片电镀层 Plated Layer of Plated Metal Strip金属塑性 Plastic Deformation金属特性 Special metallic features金属与合金 MetalAlloy金相及相律 Metal PhasePhase Rule晶粒取向（Grain-Oriented）及非晶粒取向（Non-Oriented）晶粒取向，定取向芯钢片及高硼定取向芯钢片之磁力性能及夹层系数（日工标准及美材标准） Magnetic PropertiesLamination Factor of SI-ORIENT-CORE& SI-ORIENT-CORE-HI B Electrical Steel Strip （JISAISI Standard）晶粒取向电器用硅 [硅] 钢；片–高硼低硫（LS）定取向钢片之磁力及电力性能 MagneticElectrical Properties of SI-ORIENT-CORE-HI-B-LS晶粒取向电器用硅 [硅] 钢片–高硼（HI-B）定取向芯钢片及定取向芯钢片之机械性能及夹层系数 Mechanical PropertiesLamination Factors of SI-ORIENT-CORE-HI-BSI-ORIENT-CORE Grain Orient Electrical Steel Sheets 晶粒取向电器用硅 [硅] 钢片–高硼低硫（LS）定取向钢片之机械性能及夹层系数 Mechanical PropertiesLamination Factors of SI-ORIENT-CORE-HI-B-LS晶粒取向电器用硅（硅）钢片–高硼（HI-B）定取向芯钢片，定取向芯钢片及高硼低硫（LS）定取向芯钢片之标准尺寸及包装 Standard FormsSize of SI-ORIENT-CORE-HI-B，SI-CORE， & SI-ORIENT-CORE-HI-B-LS Grain- 晶粒取向电器用硅（硅）钢片-高硼（HI-B）定取向芯钢片，定取向芯钢片及高硼低硫（LS）定取向芯钢片之厚度及阔度公差 Physical Tolerance of SI-ORIENT-CORE-HI-B， SI-ORIENT-CORE， & SI-CORE-HI-B-LS Grain 晶粒取向电器用硅钢片 Grain-Oriented Electrical Steel晶粒取向电器用硅钢片主要工业标准 International Standard – Grain-Oriented Electrical Steel Silicon Steel Sheet for Electrical Use晶体结构 Crystal Pattern晶体结构，定向格子及单位晶格 Crystal structure， Space lattice & Unit cell净磁矩 Net magnetic moment绝缘表面 Surface Insulation均热炉 Soaking pit抗磁体 Diamagnetism抗腐蚀及耐用 Corrosion & resistance durability抗化学品能力 Chemical Resistance抗敏感及环境保护 Allergic， re-cycling & environmental protection抗热超级合金 Heat Resistance Super Alloy扩散退火 Diffusion Annealing拉尺发条 Measure Tape拉伸测试（顺纹测试） Elongation test冷冲及冷锻用碳钢线枝 Carbon Steel Wire Rods for Cold Heading & Cold Forging （to JIS G3507）冷拉钢板重量表 Cold Drawn Steel Bar Weight Table冷拉钢枝材 Cold Drawn Carbon Steel Shafting Bar冷拉高碳钢线 Hard Drawn High Carbon Steel Wire冷轧钢片 Cold-Rolled Steel Sheet/Strip冷轧高碳钢–日本工业标准 Cold-Rolled （Special Steel） Carbon Steel Strip to JIS G3311冷轧或热轧钢片阔度公差 Width Tolerance of Cold or Hot-rolled sheet冷轧状态 Cold Rolled Strip冷辘（低碳）钢片的分类用、途、工业标准、品质、加热状态及硬度表 End usages， industrial standard， quality，conditionhardness of cold rolled steel strip冷辘低碳钢片（双单光片）（日工标准 JIS G3141） 73 - 95 Cold Rolled （Low carbon） Steel Strip （to JIS G 3141）冷辘钢捆片及张片的电镀和印刷方法 Cold rolled steel coil & sheet electro-plating & painting method 冷辘钢捆片及张片制作流程图表 Production flow chart cold rolled steel coil sheet冷辘钢片（拉力： 30-32公斤/平方米）在没有表面处理状态下的焊接状况 Spot welding conditions for bared （free from paint， oxides etc） Cold rolled mild steel sheets（T/S：30-32 Kgf/ μ m2）冷辘钢片储存与处理提示 General advice on handling & storage of cold rolled steel coil & sheet 冷辘钢片的“理论重量”计算方程式 Cold Rolled Steel Sheet – Theoretical mass冷辘钢片订货需知 Ordering of cold rolled steel strip/sheet理论质量 Theoretical Mass连续铸造法 Continuous casting process两面不均等锡层 Both Side Different Thickness Coated Mass两面均等锡层 Both Side Equally Coated Mass裂纹之容许深度及脱碳层 Permissible depth of flawdecarburized layer临界温度 Critical temperture马氏体不锈钢 Martensite Stainless Steel马氏铁体淬火 Marquenching埋弧焊 Submerged-arc Welding每公斤发条的长度简易公式 The Length of 1 Kg of Spring Steel Strip美材试标准的冷辘低碳钢片 Cold Rolled Steel Strip American Standard – American Society for testingmaterials （ASTM）美国工业标准–不锈钢及防热钢材的化学成份（先数字后字母排列） AISI – Chemical Composition of Stainless Steel & Heat-Resistant Steel（in order of number & alphabet）金属材料及热处理工艺常用基础英语词汇翻译对照2米勒指数Mill''s Index魔术手环Magic Tape魔术手环尺寸图Drawing of Magic Tap耐热不锈钢Heat-Resistance Stainless Steel耐热不锈钢比重表Specific Gravity of Heat – resistance steel platessheets stainless steel镍铬–日工标准G4102 63 Chrome Nickel steel to JIS G4102镍铬耐热钢Ni - Cr Heat Resistance Steel镍铬系不锈钢Nickel Chrome Stainless Steel镍铬系耐热不锈钢特性、化学成份、及操作温度Heat-Resistance Stainless Steel镍铬钼钢–日工标准G4103 64 Nickel，Chrome & Molybdenum Steel to JIS G4103疲劳测试Fatigue Test片及板材Chapter Four-Strip，Steel & Plate平坦度（阔度大于500公厘，标准回火）Flatness （width>500mm，temper：standard）破坏的检验Destructive Inspection其它焊接材料请参阅日工标准目录Other Soldering Material其它日工标准冷轧钢片（用途及编号）JIS standard & application of other cold Rolled Special Steel气焊Gas Welding潜变测试Creep Test潜变强度Creeps Strength强度Strength琴线（日本标准G3522）Piano Wires （to G3522）球化退火Spheroidizing Annealing曲面（假曲率）Camber屈服强度（降伏强度）（Yield strangth）全静钢Killed steel热力应先从工件边缘透入Heat from the Laminated Stacks Edges热膨胀系数Coefficient of thermal expansion热轧钢片Hot-Rolled Sheet/Strip热轧钢片厚度公差Thickness Tolerance of Hot-rolled sheet日本工业标准–不锈钢的化学成份（先数字后字母排列）JIS – Chemical Composition of Stainless Steel （in order of number & alphabet）日工标准（JIS G3141）冷辘钢片化学成份Chemical composition – cold rolled steel sheet to JIS G3141日工标准（JIS G3141）冷辘钢片重量列表Mass of Cold-Rolled Steel Sheet to JIS G3141日工标准JIS G3141冷辘低碳钢片（双单光片）的编号浅释Decoding of cold rolled（Low carbon）steel strip JIS G3141 日工标准下的特殊钢材Specail Steel according to JIS Standard熔铸Casting软磁Soft Magnetic软磁材料Soft Magnetic Material软焊Soldering Alloy软焊合金–日本标准JIS H 4341 Soldering Alloy to JIS H 4341上链发条Wind-up Spring上漆能力Paint Adhesion伸长度Elongation渗碳体Cementitle渗透探伤法Penetrate inspection生产流程Production Flow Chart生锈速度表Speed of rusting时间淬火Time Quenching时间效应（老化）及拉伸应变Aging & Stretcher Strains释出硬化不锈钢Precipitation Hardening Stainless Steel双相辗压镀锡薄钢片（马口铁/白铁皮）Dual-Reduction Tinplate顺磁体Paramagnetic碳钢回火Tempering碳污染Prevent Carbon Contamination特点Characteristic特殊钢Special Steel特殊钢以用途来分类Classification of Special Steel according to End Usage特殊钢以原素分类Classification of Special Steel according to Element提防过份氧化No Excessive Oxidation铁磁体Ferromagnetism铁铬系不锈钢片Chrome Stainless Steel铁及非铁金属Ferrous & Non Ferrous Metal铁锰铝不锈钢Fe / Mn / Al / Stainless Steel铁线（低碳钢线）日工标准JIS G 3532 Low Carbon Steel Wires （Iron Wire ）to JIS G 3532铁相Steel Phases同素变态Allotropic Transformation铜基层金属Copper as Base Metal透磁度Magnetic Permeability退火Annealing退火时注意事项Annealing Precautionary外价电子Outer valence electrons弯度Camber完全退火Full Annealing物理性能Physical Properties物料科学Material Science物料科学定义Material Science Definition锡层质量Mass of Tin Coating （JIS G3303-1987）锡基、铅基及锌基轴承合金比较表Comparison of Tin base，Lead baseZinc base alloy for Bearing purpose细线材、枝材、棒材Chapter Five Wire，Rod & Bar显微观察法Microscopic inspection线材/枝材材质分类及制成品ClassificationEnd Products of Wire/Rod线径、公差及机械性能（日本工业标准G 3521）Mechanical Properties （JIS G 3521）相反旋转Opposite span相律Phase Rule锌包层之重量，铜硫酸盐试验之酸洗次数及测试用卷筒直径Weight of Zinc-Coating，Number of Dippings in Cupric Sulphate TestDiameters of Mandrel Used for Coiling Test锌镀层质量Zinc Coating Mass锌镀层质量（两个不同锌镀层厚度）Mass Calculation of coating （For differential coating）/MM锌镀层质量（两个相同锌镀层厚度）Mass Calculation of coating （For equal coating）/MM亚共晶体Hypoeutetic Alloy亚铁磁体Ferrimagnetism亚铁释体Hyppo-Eutectoid延轧Rolling颜色Colour易车（快削）不锈钢Free Cutting Stainless Steel易车（快削）不锈钢拉力表Tensile Strength of Free Cutting Wires易车（快削）不锈钢种类Type of steel易车不锈钢及易车钢之不同尺寸及硬度比较Hardness of Different Types & Size of Free Cutting Steel易车碳钢Free Cutting Carbon Steels （to JIS G4804 ）易溶合金Fusible Alloy应力退火温度Stress –relieving Annealing Temperature应用材料Material Used硬磁Hard Magnetic硬磁材料Hard Magnetic Material硬度Hardness硬度及拉力Hardness & Tensile strength test硬焊Brazing Alloy硬化Work Hardening硬化性能Hardenability用含碳量分类–即低碳钢、中碳钢及高碳钢Classification According to Carbon Contains用途End Usages用组织结构分类Classification According to Grain Structure幼珠光体Fine pearlite元素的原子序数Atom of Elements原子的组成、大小、体积和单位图表The size，mass，charge of an atom，is particles （Pronton，NentronElectron）原子的组织图Atom Constitutes原子及固体物质Atomsolid material原子键结Atom Bonding圆钢枝，方钢枝及六角钢枝之形状及尺寸之公差Tolerance on ShapeDimensions for Round Steel Bar，Square Steel Bar，Hexagonal Steel Bar圆径及偏圆度之公差Tolerance of Wire Diameters & Ovality圆面（“卜竹”）发条Convex Spring Strip再结晶Recrystallization正磁化率Positive magnetic susceptibility枝/棒无芯磨公差表（μ）（μ = 1/100 mm）Rod/Bar Centreless Grind Tolerance枝材之美工标准，日工标准，用途及化学成份AISI，JIS End UsageChemical Composition of Cold Drawn Carbon Steel Shafting Bar直径，公差及拉力强度Diameter，ToleranceTensile Strength直径公差，偏圆度及脱碳层的平均深度Diameter Tolerance，OvalityAverage Decarburized Layer Depth置换型固熔体Substitutional type solid solution滞后回线Narrow Hystersis中途退火Process Annealing中珠光体Medium pearlite周期表Periodic Table轴承合金Bearing Alloy轴承合金–日工标准JIS H 5401 Bearing Alloy to JIS H 5401珠光体Pearlite珠光体及共释钢Pearlite &Eutectoid主要金属元素之物理性质Physical properties of major Metal Elements转变元素Transition element自发上磁Spontaneous magnetization自由度Degree of freedom最大能量积Maximum Energy Product（to JIS G3521，ISO-84580-1&2）化学成份分析表Chemical Analysis of Wire Rod305，316，321及347之拉力表Tensile Strength Requirements for Types 305，316，321347A1S1-302 贰级线材之拉力表Tensile Strength of A1S1-302 WireGrain Oriented & Non-Oriented 电器用硅[硅] 钢片的最终用途及规格End UsageDesignations of Electrical Steel Strip Oriented Electrical Steel SheetsSK-5 & AISI-301 每公尺长的重量/公斤（阔2.0-10公厘）Weight per one meter long （kg）（Width 2.0-10mm）SK-5 & AISI-301 每公斤长的重量/公斤（阔100-200公厘）Weight per one meter long （kg）（Width 100-200mm）SK-5 & AISI-301 每公斤之长度（阔100-200公厘）Length per one kg （Width 100-200mm）SK-5 & AISI-301 每公斤之长度（阔2.0-10公厘）Length per one kg （Width 2.0-10mm）。
《商务英语函电教程》Unit 4发出要求与拒绝邀请
A firm offer will include the following:
a. An expression of thanks for the enquiry, if any;
b. Name of commodities, quality, quantity, and specifications; c. Details of prices, terms of payment, commissions, or discounts, if any; d. Packing and date of delivery; e. The validity of the offer; f. An expression of hope that the offer will be accepted. (optional)
Specimen Letter-2（Non-firm Offer） Green Plants Co., Ltd.
Rm. 2808 Kai Tak Comm. Centre, 317 Des Voeux Road, Central Hong Kong Tel: 00852-63108921 E-mail: greenplants@
The original offerer or the seller now becomes the offeree and he has the full right of acceptance or refusal. In the latter case, he may make another counter offer of his own. This process can go on for many a round till business is finalized or called off. When an offeree rejects an offer, he should write to thank the offerer and explain the reason for the rejection. Not to do so would show a lack of courtesy.
金属材料专业英语词汇
AISI –ChemicalComposition of Stainless Steel & Heat-Resistant Steel(in order of number &Alphabet)|美国工业标准–不锈钢及防热钢材的化学成份(先数字后字母排列)[金属材料专业英语词汇]\r\n
Annealing|退火[金属材料专业英语词汇]\r\n
Annealing ofThe Electrical Steel Sheet|电器用钢片用家需自行应力退火原因[金属材料专业英语词汇]\r\n
Annealing Precautionary|退火时注意事项[金属材料专业英语词汇]\r\n
Antiferromagnetism|反铁磁体[金属材料专业英语词汇]\r\n
Antiferromagnetism|反Байду номын сангаас磁体[金属材料专业英语词汇]\r\n
Application|用途[金属材料专业英语词汇]\r\n
ASTMA313 – 1987Chromium – Nickel StainlessAnd Heat-resisting Steel Spring Wire –ASTMA313 – 1987|铬镍不锈钢及抗热钢弹簧线材–美国材验学会[金属材料专业英语词汇]\r\n
Classification of Special SteelAccording to Element|特殊钢以原素分类[金属材料专业英语词汇]\r\n
Fenwal 05-14 to 35-70 Series 120 VAC Direct Spark
Fenwal continues advancing direct spark gas ignition technology by employing its legendary design experience to develop a new line of microprocessor based ignition controls for the 120 VAC marketplace. The 35-70, 120 VAC DSI is the most recent advance in Fenwal's broad product mix to serve this market. Providing safe gas ignition control and flame monitoring for 120 VAC gas burner systems, the 35-70's microprocessor based design offers a wide range of configurations in a cost effective package.The 35-70 is the latest in a long line of 120 VAC controls and replaces the following Fenwal analog controls: the 05-13 (circa 1960), 05-14 (circa 1970) and 05-38 (circa 1985). This conversion guide provides information to quickly and safely convert an applicationvariety of applications.AGENCY APPROVALAgency ComparisonMULTIPIN CONNECTORTerminal Designation and Size ComparisonLt. Blue Brown White Yellow Black Purple Gray N/A 2 Pin Header N/A N/AAlarmValve Power120 VAC (Neutral)Valve Neutral120 VAC Input (Hot)Burner GroundRemote Flame SensorLocal SenseFlame Sense TestPinsIsolated Valve Models N/AV1L2V2L1N/A S1E2N/A L3V21/4”3/16”3/16”3/16”1/4”3/16”1/4” N/A .045” SQ.1/43/16”N/A 1/4”1/4”1/4”1/4”N/A 1/4”1/4”N/A 1/4” 1/4”DESCRIPTIONTerminal DesignationQUICK CONNECT TERMINAL35-7005-14NC V1L2V2L1B. GND S1N/A FC+,FC-L3V2111087621N/A N/A N/A 05-1435-70PIN LOCATIONWIRE COLOR35-70 ONLYTerminology - Single Spark and Sense vs. Local SenseOne important note on wiring the 35-70 has to do with terminology and wiring for flame sense. In all of the new 120 VAC control literature, especially that for the 35-70, we have made a point to use the term "Single Spark and Sense" rather than the more colloquial "Local Sense" when referring to sensing flame on the spark electrode. The 05-14s have local sense where the flame sense signal travels to the board along a separate wire (not the H.V. wire) to a terminal on the control typically identified as E2.This is a very important distinction. Single Spark and Sense is easier to wire as it eliminates the need for an additional sense wire, because the high voltage wire serves the dual role of supplying spark energy to the electrode and passing the flame sense current to the control.New Grounding SchemeFor all models of the 35-70, the B.GND terminal is used to ground the burner and to complete the flame current signal circuit. This terminal is new for systems that used the 05-14. This terminal must be connected to the burner (chassis) ground not only to ensure the best, long term, stable flame signal, but also to ground the burner for prop-er sparking, especially in the case of single spark and sense. See wiring diagrams for conversion of 05-14 wiring.The use of a burner ground terminal eliminates the problem of loss of flame sense signal due to a missing or loose neutral or ground (green) wire at the 120 VAC power source. The 35-70 has been designed such that reversing the polarity of the 120 VAC line does not cause a loss of flame signal. Thus, the 35-70 provides a more reliable flame signal along with a reduction of nuisance lockouts, due to its design and the use of the B.GND terminal.Electrode requirements for Single Spark and Sense vs. Local Sense Applications Since 05-14s with Local Sense are replaced by 35-70s with Single Spark and Sense, the electrode must bere-wired or replaced with a simpler electrode configur-ation.Typically, a local sense electrode, see figure below, has two electrodes on the same bracket. This type of electrode assembly requires that a high voltage wire and flame sense wire be attached to each electrode and wired back to the control. A single spark and sense electrode has only one electrode on the bracket and requires just the high voltage wire and a grounded burner. See figure below.05-1435-7035-7005-14 to 35-70 Wiring Comparison05-14 CASE AND COVER35-70 CASE AND COVER 05-14 STANDOFF35-70 STANDOFFNOTES35-70 does not have a manual reset button and does not have a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 does not have a manual reset button and does not have a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 does not have a manual reset button and does not have a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 does not have a manual reset button and does not have a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 does not have a manual reset button and does not have a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 does not have a manual reset button and does not have a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 does not have a manual reset button and does not have a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 does not have a manual reset button and does not have a vertical 1/4" Q.C. terminal on high voltage spark transformer, see Note 235-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer, see Note 2Isolated valve contacts, see Note 1, 35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformerIsolated valve contacts, see Note 1, 35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high oltage spark transformer35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer 35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer, see Note 2Isolated valve contacts, see Note 1, 35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformerThis 05-14 control has a special two stage start up with pilot and main valve control This 05-14 control has a special two stage start up with pilot and main valve control35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer, see Notes 2 and 3, same as 05-142401-025 except potted with 6” lead wire on S135-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer,same as 05-142201-005 except potted - see Note 3 and leadwire for S1, E2 jumped to S1 to convert to local sense, see Note 2Isolated valve contacts, see Note 1, customer P/N, double conformal coating, 35-70 has single conformal coat and has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer, same as 05-142301-001Isolated valve contacts, see Note 1, customer P/N, double conformal coating, 35-70 has single conformal coat and a horizontal 1/4"Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer, same as 05-142301-00535-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer, same as 05-142401-031, except 6” lead wire on S1 with duplex M/F terminal, Potted - see Note 3, Sometimes wired as local sense35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer, same as 05-142401-035, except Potted - see Note 3Same as 05-143401-005 with customer P/N: on label, This 05-14 control has a special two stage start up with pilot and main valve control. Double conformal coat.Assigned special part number because of sequential serial numbers assigned to labels. 35-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer, same as 05-142401-00035-70 has a horizontal 1/4" Q.C. where the 05-14 has a vertical 1/4" Q.C. terminal on high voltage spark transformer,same as 05-140201-035 except potted, see Note 3 and leadwire for S1, E2 jumped to S1 to convert to local sense, see Note 2Same as an 05-142401-000 with special feature 05-982055-001 which is a horizontal 1/4” Q.C. instead of vertical1/4” Q.C. on high voltage transformer. Use 05-128714-001 circuit breaker assembly (5 terminal), not available on the 35-70Isolated Valve Contacts, same as an 05-142301-000 without R21 MOV surge supressor - surge supressor is standard on 35-70Assigned 05-14 special feature number because this version does not use the standard vertical 1/4” Q.C. on high voltage spark trans-former, same as 05-142401-001Assigned 05-14 special feature number because this version does not use the standard vertical 1/4” Q.C. on high voltage spark trans-former, same as 05-142201-00105-14 to 35-70 Cross Reference Chart35-70 CROSS REFERENCE35-705600-00135-705600-00135-705600-00535-705600-00535-705601-00135-705601-00135-705601-00535-705601-00535-705600-00135-705600-00135-705600-00535-705600-00535-704600-00135-704600-00535-705601-00135-705601-00535-705601-00535-704601-005no cross no cross35-705701-00535-705700-00535-704600-00135-704600-00535-705701-00135-705701-005no cross 35-705601-00135-705700-00535-705601-00105-704600-00135-705601-00135-705600-001EXISTING PART #05-140201-00005-140201-00105-140201-00505-140301-00505-140401-00005-140401-00105-140401-00505-140401-02505-142201-00005-142201-00105-142201-00505-142201-02505-142301-00105-142301-00505-142401-00105-142401-00505-142401-02505-142501-00505-143401-00105-143401-02505-149004-02505-149005-02505-149009-00105-149009-00505-149013-03105-149013-03505-149014-00505-149015-00005-149016-03505-149018-001 05-149021-00005-149022-00105-149024-001NOTE 2: 05-14 controls with part numbers that end in -X2X and -X3X, i.e. 025 or 035, are not identified in the 05-14 part numbering scheme in the 05-14 data sheet. The 2 and 3 are used to indicate that a gas valve relay with higher current capacity than was standard on 05-14s was used. The 35-70s have the higher current capacity relay as standard equipment and therefore a special designation is no longer required.NOTE 1: 35-704XXX-XXX is a special version of the 35-70 that has isolated valve contacts. Please see numbering scheme on Page 6 to determine the physical configuration and operating characteristics of the 35-704XXX-XXX models in this cross reference list.NOTE 3: 05-14 controls that are enclosed in an open top potting shell and encased in dieletric potting material for protection against washdown and extreme vibration are not identified in the 05-14 part numbering scheme. These configurations were assigned special part numbers, such as 05-149XXX-XXX where the 9 signifies that the control is a special configuration.Isolated Gas Valve ContactsIsolated Gas Valve ContactsEnclosure Configurations and Wiring Options 5 = Case and Cover Quick Connects6 = Integral Stand-OffsQuick Connects7 = Potted Quick ConnectsAssemblies and Non-Standard Configurations 8 = Assemblies9 = Non Standard ConfigurationA 9 in this location of the part number (EXAMPLE: 35 704 - XXX) identifies this configuration as a non-standard design. The part number does not follow the part numbering system. Consult factory for operating characteristics of this control.Trial for Ignition Time (TFI)1 = 4 seconds3 = 7 seconds 5 = 10 seconds 7 = 15 secondsPre-Purge Time 0 = None1 = 15 seconds2 = 30 seconds 5 = 5 secondsInter-Purge Time 0 = NoneNumber of Ignition Trials,Flame Sense Method and Lock Out Reset Method 0 = 1 try, single spark and sense Thermostat / power off reset 1 = 1 try, remote senseThermostat / power off resetX 0 X 35 - 70 4- X X XorNOTE:The 35-704 is a special version of the 35-70 product that has been developed to replace the 05-1403XX-XXX and 05-1405XX-XXX that have isolated valve contacts. This product will not be promoted for new applications and therefore is not mentioned in any product literature. This numbering scheme is solely used to assist customers with determining the operating characteristics of the controls identified as the replacements for 05-1403XX-XXX and 05-1405XX-XXX listed in this Conversion Guide.901400 MAIN STREET, ASHLAND, MA 01721TEL: (508) 881-2000FAX: (508) These instructions do not purport to cover all the details or variations in the equipment described, nor do they provide for every possible contingency to be met in connection with installation, operation and maintenance. All specifications subject to change without notice.Should further information be desired or should particular problems arise which are not covered sufficiently for the purchaser’s purposes, the matter should be referred to KIDDE-FENWAL,Inc., Ashland, Massachusetts.© 2001 Kidde-Fenwal, Inc, Printed in U.S.A. CP。
博卡电焊机 生成器说明书
Issued February 2018 • Index No. ED/4.4Welder/generator is warranted for three years, parts and labor. Engine is warranted separately by the engine manufacturer.Easier mobility and uses less truck space and payload With its intuitive design, the daily maintenance of our Bobcat welder/generators is faster and easier.Easier Maintenance Safer, more productiveBobcat 250 EFI model shown.The most popular welder/generator • Quieter to operate • Smaller and lighter• More fuel efficient with EFI • Easier to maintainGas or LP Engine-Driven Welder/AC GeneratorBobcat225and 250Miller Electric Mfg. LLCAn ITW Welding Company 1635 West Spencer Street P.O. Box 1079Appleton, WI 54912-1079 USAEquipment Sales US and CanadaPhone: 866-931-9730FAX: 800-637-2315International Phone: 920-735-4554International FAX: 920-735-4125Rugged welder/generators are great for stick and flux-cored welding.Designed for maintenance/repair operations, construction, farm,ranch and generator use.The Bobcat™AdvantageDesigned for reliabilityFrom Appleton, Wis. USA, our welder/generators are the most rugged, durable and long-lasting in the industry. We manufacture them to exceed requirements for extreme working conditions and they are hard-working from the core:•Copper windings and iron generator components for a quality-built machine •Lugged—not soldered—heavy internal leads for better field durability •Superior cooling technologyfor maximum performanceand engine life•Super-tough armor toprotect the welder/generator from accidental impact•Protective armor doors to cover the weldstuds and receptacles as required by OSHAand CSA for jobsite safety•Lift hook integrated into the center frame,which bolts to the machine’s base forgreater durabilityLong runtimesLarge 12-gallon fuel capacity means manyhours of run time before refueling.Versatile AC and DC weld outputProvides quality welds on all types of metals.DC is smooth and easy to run while AC stickis used when arc blow occurs.Quieter and better sound*Significant improvements in soundlevel and quality offer better jobsitecommunication, which provides a safer,more efficient working environmentfor you and your crew. Bobcatwelder/generators have rotated theengine toward the front to create moreefficient airflow, resulting in significantly quieter operation. Now you can start your job earlier in the day and end it later, as well as work around hospitals, businesses, and residential areas.Smaller and lighter design*Bobcat welder/generators take up lessspace on trucks and trailers—leavingmore room on your truck for otherequipment and tools. Plus, they’reeasier to move safely around jobsites—even with weld cables and runninggear attached.*Compared to previous model Easier maintenance*With its intuitive design, the daily maintenance of our Bobcat welder/generators is faster and easier. With front panel maintenance displays, you know when your equipment needs to be serviced. And servicing is simple because of:•Oil checks that can be performed from the top by the front panel •Toolless panels that allow for quick access•Single-side fuel fill and oil drain/filterS fEasier mobilit andAir filterOil fill Oil drain Oil level checkFuel fill Oil filterFuel filter•Front panel fuel and sight gauges provide convenient fuel level indication•Smoother weld output and better generator power while welding •More weld output than 225-amp welder generators—72 percent more power for MIG/flux-cored, 67 percent more for AC welding, and 11 percent more for DC stick Electronic fuel injection (EFI)EFI gas engines optimize the air/fuel ratio forall engine speeds and engine loads, resultingin lower operational costs, fewer emissions, longer runtimes and better performance when compared to carbureted models. TheBobcat™250 Additional FeaturesBobcat 250 recommended option2Exclusive engine and generator packaging design operates cooler and more efficientlyThe engine is rotated towards the front to create more efficient airflow. More efficient airflow and exclusive engine location are significant contributors to reduced sound level and size reduction.Hot air recirculation is eliminated when machine is mounted in tight spots, and internal parts are kept cool for optimal performance.3Reversed Generator AirflowTo select a generator that has enough power output in watts, add the watts for the items you want tosimultaneously run. Tools and appliances with induction motors may require three to seven times the listed wattage when starting. All data listed is approximate —check your tool/appliance for specific wattage requirements.Starting Running Equipment Watts Watts Barn Cleaner (5 hp) 11,600 3,000Silo Unloader (5 hp) 12,200 4,300Portable Conveyor (1/2 hp) 3,400 1,000Milker (5 hp) 10,500 2,800Hand Drill (1/2 inch) 600 600Circular Saw (8-1/4 inch) 1,400 1,400Air Compressor (1-1/2 hp) 8,200 2,200Flood Lights (Vapor) 1,250 1,000Refrigerator/Freezer 2,200 700Sump Pump 1,300 800Millermatic ®212 Auto-Set ™ 6,500 6,500MIG Welder (230 V)Spectrum ®625 X-TREME ™ 6,900 6,900(30 A, 230 V, 1/2-inch cut)The Bobcat ™Generator Power AdvantageAccu-Rated ™—not inflated generator powerOur Accu-Rated ™11,000 watts (12,000 with EFI)of usable peak power isdelivered for a minimum of 30 seconds. Accu-Rated means peak power is usable for maximum generator loads such as plasma cutting, Millermatic ®MIG welders and motor starting. Accu-Rated peak power beats the competition’s very short-duration peak or surge power. Use your peak power, it’s more than a number.Smooth power —not spike powerRevolutionary ten-degree skewed-rotor design optimizes generator performance for smootherpower —not spiked power found with other brands. Better power —better performance.Typical equipment power usageBobcat welder/generators will easily start and run the following equipment:Waveform ComparisonBobcatCompetitorTools and motors are designed to operate within 10 percent of 120/240 V. The powergenerator of the Bobcat provides strong power while keeping the voltage within 10 percent of 120/240 V.This increases tool/motor performance and life.Generator Power Curve10203040506070809010011020406080100120140160180200220AC Power Amps at 120 V025*******108125150050100150200216132264250300A C P o w e r V o l t sAC Power Amps at 240 V4Engine Specifications (Engines warranted separately by the engine manufacturer.)Model Bobcat 225Bobcat 250Welding Mode CC/AC CC/DC CV/DCCC/AC CC/DC CV/DCProcess Stick/TIG Stick/TIG 1MIG/FCAW Stick/TIG Stick/TIG 1MIG/FCAWRated Weld Output at 104°F (40°C)2150 A at 25 V, 100% duty cycle 225 A at 25 V, 100% duty cycle 200 A at 20 V, 100% duty cycle 225 A at 25 V, 100% duty cycle 250 A at 25 V, 60% duty cycle 250 A at 25 V, 100% duty cycle 250 A at 28 V, 100% duty cycle 275 A at 25 V, 60% duty cycleAmp/Volt Ranges 60–160 A 40–225 A 19–28 V 40–250 A 40–250 A 17–28 VSingle-Phase Generator Power Peak: 11,000 wattsContinuous: 9,500 watts 120/240 V, 88/44 A, 60 HzPeak: 11,000 wattsContinuous: 9,500 watts 120/240 V, 88/44 A, 60 Hz EFI ModelPeak: 12,000 wattsContinuous: 10,500 wattsSound Levels at Max. Load/150 A 73.5 dB/72 dB72.5 dB/72 dBNet Weight 3485 lb. (220 kg)501 lb. (227 kg)Dimensions H: 28 in. (711 mm)H: 32.75 in. (832 mm) (to top of exhaust)W: 20 in. (508 mm)D: 40.5 in. (1,029 mm)H: 28 in. (711 mm)H: 32.75 in. (832 mm) (to top of exhaust)W: 20 in. (508 mm)D: 40.5 in. (1,029 mm)Certified by Canadian Standards Association to both the Canadian and U.S. Standards.Note: Derate outputs up to five percent when using LP fuel. 1) DC TIG available above 80 amps. 2) Rated at sea level. 3) Net weight without fuel.*Fuel stabilizer is recommended for gas engines that are used infrequently.**Hose and LP Tank Mounting Assembly and setup are required.Performance DataMounting SpecificationsA.20 in. (508 mm)B.16.5 in. (419 mm)C.1.75 in. (44.5 mm)D.5.12 in. (130 mm)E. 22.3 in. (566 mm)F. 40.32 in. (1,024 mm)G..406 in. (10.3 mm) diameterF r o n t P a n e l0.000.250.500.751.001.251.501.752.0005010015020025030024681012Fuel ConsumptionPower KVA at 100% Duty CycleWeld Amperes at 100% Duty CycleU .S . G a l./h o u rFuel Consumption Data•12-gallon fuel capacity.•On a typical job using 1/8-inch 7018electrodes (125 A, 20% duty cycle) expect about 20 hours (gas) of operation.•Welding at 150 A, 40% duty cycle uses approxi m ately 3/4 gallon per hour —about 16 hours of operation (gas).•Under a continuous load of 4,000 watts of generator power, the Bobcat would run for about 14 hours (gas) of operation.5Note: See or the Full-line Catalog to compare to Trailblazer models.Function and Benefit Guide1.Maintenance display provides fuel level (250 models only), engine hours and oil change interval information.2.Weld process selector switch makes choosing between stick, wire and TIG processes easy. Switch also auto m atically changes polarity with process selection to make sure the machine is easy to set with little effort or knowledge (on 225 model, weld process selector switch is combined with coarse range control).3.Coarse range control225 model —Three DC stick/TIG, one AC TIG, and one wire range are available for output control. Stick ranges are designed forelectrode diameters (3/32, 1/8 and 5/32 inch) making these models very easy to set.250 model —Four stick/TIG and two wire ranges are available for output control. Stick ranges are designed for electrode diameters (3/32, 1/8, 5/32 and 3/16 inch) making these models very easy to set.4.Fine adjust control makes it easy to fine tune amperage within a coarse range. Set control above 7 for best power while welding and to 10 for generator-only use.5.Engine control switch is used to start the engine and then select between auto idle and high speed lock positions.6.Engine choke control is used for easy engine starting.Note: No choke necessary on EFI models.7.120/240 V receptacle with circuit breaker.(For matching plug, order 119172.)8.120 V GFCI receptacles with circuit breakers.Choose the Right Bobcat ™Engine Drive6Order the following from Miller Service Parts.Genuine Miller ®Options *Available as factory option. See ordering information on back page.Genuine Miller ®AccessoriesNever Flat ™TiresAvailable on Bobcat and Trailblazer running gear.•Eliminate costly jobsite downtime•Maintain constant tire pressure and will not develop flats•Protect against punctures•Preserve maneuverability, even when weighed down with heavy welding cable Off-RoadRunning Gear 300909 Gas/LP, with inner tubes 300910 Gas/LP, with Never Flat tires Includes fourheavy-duty 15-inch tires and a rugged handle to provide maximum maneuverability.Off-Road Running Gear withProtective Cage and Never Flat Tires300912 Gas/LP Running gear and rugged cage withcable holders protects your investment and is easy to move around the jobsite.Multi-Terrain Running Gear 300913 Gas/LP,with inner tubes 300914 Gas/LP,with Never Flat tires Includes two heavy-duty 15-inch tires, two 8-inch rubber swivel casters and a heavy-duty handle. Recommended for all surfaces and applications, and is easy to move around the jobsite.Protective Cagewith Cable Holders 300921Gas/LP Rugged cage with cable holders protects yourinvestment. Can beused with running gear, gas cylinder mounting assembly, LP tank mounting assembly, or with trailer.Gas CylinderMounting Assembly 300918GasDesigned for use with multi-terrain running gear, protective cage, or by itself. Includes base tray with bottlebracket, vertical support rack and safety chain.Note: Not for use with LP tank mounting assembly.Not recommended for use with protective cover.Hose and LP Tank Mounting Assembly 300917LPDesigned for use with multi-terrain running gear, protective cage,or by itself. Includes bracket and clamp tomount 33- and 43-pound tanks horizontally, and hose with fittings to converter.Note: Not for use with gas cylinder mounting assembly.Not recommended for use with protective cover.Protective Covers 300919 For gas models without protective cage or running gear (shown)300920 For gas models with protective cage and/or running gearHeavy-duty, water-resistant and mildew-resistant covers protect and maintain the finish of the welder.7MIG/Flux-cored WeldingMillermatic 141 and 211 shown.Millermatic ®141 907612See literature DC/12.42Millermatic ®211 907614See literature DC/12.58Millermatic ®212 Auto-Set ™907405See literature DC/12.46The Millermatic line of MIG welders are complete arc welding power source, wire feeder and gun packages designed for portability and ease of use.Note: The Millermatic machines can be operated utilizing auxiliary power.SuitCase ®X-TREME ™8VS Wire Feeder 951582SuitCase ®X-TREME ™12VS Wire Feeder 951543Lightweight, voltage-sensing wire feeders include secondary contactor, gas valve, drive roll kit and Bernard ™BTB Gun 300 A. See literature M/6.42.Spoolmatic ®30A Spool Gun 130831Air-cooled, 200-amp,one-pound spool gun for aluminum MIG.See literature M/1.73.Requires WC-115A control (137546011).Spoolmate ™3035Spool Gun 195016Use with SGA 100C control and heavy-duty barrel. Spool gun for aluminum andother wires. Four-inch spools; .023–.035 inch (0.6–0.9 mm) aluminum, steel and stainless steel. Rated at 150 amps, 60 percent duty cycle with 20-foot (6 m) cable assembly.SGA 100C Control 043857SGA with contactor required to connectSpoolmate 3035 to CV engine drive. Includes 10-foot (3 m) 115 V power cable and plug, 6-foot (1.8 m) interconnecting cable, and 5-foot (1.5 m) gas hose.Heavy-Duty Barrel for Spoolmate 3035195375Use for demanding applications, rated at 200 A,60 percent duty cycle.Stick (SMAW) WeldingWeld Leads2/0 Stick Cable Set, 50 ft. (15 m) 173851Consists of 50-foot (15 m) 2/0 electrode cable with holder, and 50-foot (15 m) work cable with clamp. 350 A, 100% duty cycle.2/0 Stick Cable Set, 100/50 ft. (30.5/15 m)043952Consists of 100-foot (30.5 m) 2/0 electrode cable with holder, and 50-foot (15 m) work cable with clamp. 300 A, 100% duty cycle.TIG (GTAW) WeldingDynasty ®210 Series For portable AC/DC TIG. See literature AD/4.81.Multiprocess WeldingMultimatic ™200 907518Portable, all-in-one multiprocess package weighs only 29 pounds (13.2 kg), and features excellent arc characteristics. Exclusive multi-voltage plug (MVP ™) provides flexibility to plug into 120- or 240-volt power. Take it anywhere you need to MIG, TIG or stick weld. See literature DC/12.57.Plasma CuttingSpectrum 375 X-TREME and 625 X-TREME shown.Spectrum ®375 X-TREME ™907529See literature PC/9.2.Spectrum ®625 X-TREME ™907579See literature PC/9.6.Spectrum ®875 907583See literature PC/9.8.The Spectrum 375 X-TREME and 625 X-TREME come complete with protective X-CASE ™(not shown).Trailers and HitchesHWY-Mid Frame Trailer 3014381,424-pound (646 kg) capacity highway trailer with welded steel tubing frame, heavy-duty axle with roller bearing hubs and leaf-springsuspension. Includes jack stand, fenders, lights,and dual hitch with 2-inch (50 mm) ball hitch and 3-inch (76 mm) lunette eye.Note: Trailer is shipped unassembled.Cable Tree 043826Provides an area to conveniently wrap weld cables and extension cords.2-In-1 Document/Fire Extinguisher Holder 301236Stores documents and holds a five-pound fire extinguisher.Note: Holder shown mounted on trailer. Fire extinguisher notincluded.Genuine Miller ®Accessories (Continued)Ordering InformationEquipment and Options Stock No. Description Qty. PriceBobcat™225907498001Kohler engine, base model907498 Kohler engine with GFCI receptaclesBobcat™250907500001 Kohler engine, base model907500 Kohler engine with GFCI receptacles907500002 Kohler engine with electric fuel pumpBobcat™250 EFI 907502Kohler engine, base modelBobcat™250 LP 907504Kohler engine with GFCI receptaclesField Options Options listed below can be added to the above packages. Installation is required.GFCI Receptacles 300975Electric Fuel Pump 300976 Recommended for gas engine operations at altitudes above 5,000 feetSpark Arrestor300924Remote Oil Drain and Filter Kit 300923 Front mount for KohlerFull KVA Adapter Cord300517Full KVA Plug 119172Engine Tune-Up Kits See page 6. Order from Miller Service PartsAccessoriesOff-Road Running Gear300909Gas/LP models, with inner tubes300910Gas/LP models, with Never Flat™tiresOff-Road Running Gear with Protective Cage300912 Gas/LP models, with Never Flat™tires.Multi-Terrain Running Gear300913Gas/LP models, with inner tubes300914Gas/LP models, with Never Flat™tiresProtective Cage with Cable Holders300921 Gas/LP modelsGas Cylinder Mounting Assembly 300918 Gas models. Not for use with LP tank mounting assembly.Not recommended for use with protective coverHose and LP Tank Mounting Assembly 300917 LP models. Not for use with gas cylinder mounting assembly.Not recommended for use with protective coverProtective Covers See page 6MIG/Flux-cored WeldingMillermatic®Series MIG Welders See page 7SuitCase®X-TREME Wire Feeders See page 7Spoolmatic®30A Spool Gun 130831 Requires WC-115A Control. See literature M/1.73WC-115A Control 137546011 See literature M/1.73Spoolmate™3035 Spool Gun 195016 See literature M/1.5SGA 100C Control 043857 See literature M/1.5Heavy-Duty Barrel for Spoolmate 3035195375 See literature M/1.5Stick Welding See page 7TIG Welding See page 7Multiprocess Welding See page 7Plasma Cutting See page 7Trailers and HitchesHWY-Mid Frame Trailer301438Trailer with lights, fenders and dual hitch. For highway useCable Tree 043826Trailer-mounted cable holder2-In-1 Document/Fire Extinguisher Holder301236 Stores documents and holds a five-pound fire extinguisherDate: Total Quoted Price:Distributed by:©2018 Miller Electric Mfg. LLC。
灯具（Lampsandlanterns）
灯具（Lamps and lanterns）First, the purchase of lamps three considerationsLighting is the most charming flirt in the room. Different shapes, colors, materials and sizes can create different lighting effects for different rooms, showing different living expressions. Now, in the face of the market, a myriad of forms of lamps and lanterns, do you feel a little confused? In fact, in the purchase of lamps, you have to consider mainly from the following three aspects: first of all, according to their actual needs and personal preferences to choose the style of lamps. For example, you pay attention to the practical light, you should pick black, deep red and other dark Department of the ceiling lamp or floor lamp, and if you pay attention to decorative, but also the pursuit of modern style, you can choose lively points of lighting. If you are interested in ethnic characteristics of the lamps and lanterns, you can choose sculpture craft floor lamp.Secondly, the color of lamps and lanterns should be in harmony with the home decoration style. The room lights must consider the indoor furniture style, wall color, home appliances color, otherwise the whole tone light and room is not the same, it will be self defeating. For example, the color of interior wallpaper is light colored, it should be a warm incandescent lamp as a light source, so that you can create a bright and soft light environment.Finally, the size of the lamp should be combined with the indoor area, the number of furniture and the corresponding size. Such as 12 square metres of small living room should be used below200 mm diameter ceiling lamp or wall lamp, the number of lamps and lanterns should match the appropriate size, so as not to appear too crowded. 15 square meters in the living room, the ceiling lamps diameter of about 300 mm or more fork floral chandeliers, lamps of the largest diameter shall not exceed 400 mm. On both sides of the wall hung with spotlights or wall lamp foil, the effect will be betterTwo, buy Lamps adhere to the six principlesThe principle of simplicity of lighting should play an important role in the room. Too complex modeling, too many complex colors, are not suitable for the design of a simple room.Convenience principle, most people have experienced the embarrassment of changing the ceiling lamp bulb: stepping on the table, stepping on the chair, holding the head 90 degrees, lifting your arms to the ceiling of 2.5 meters or more. When choosing lamps, be sure to consider changing the light bulb.The principle of energy saving, energy-saving light bulbs, electricity saving, good lighting, and no heat distribution, suitable for long lamps. Energy saving light bulbs are mostly standard screw, and there are two kinds of chandelier caliber, one is standard, you can use energy-saving light bulbs; one is non-standard, can not use energy-saving light bulbs. Choose when to pay attention: spotlights are mostly non energy saving products.Safety principle must choose the lamps and lanterns of regularfactory. Regular products are marked with total load, according to the total load, you can determine the number of Watts used in the bulb, especially for the long chandelier is the most important, that is: head count * per lamp wattage = total load. In addition, damp large bathroom, kitchen should choose waterproof lamps and lanterns.Different functional principles, the use of functional rooms, lighting should be installed in different styles, lighting. The living room lamps should be chosen bright and beautiful; the bedroom should be chosen to lie in bed and feel the glare of the lights; lamps of children room should choose color gorgeous changeable style; style toilet should choose waterproof lamps simple; the kitchen should choose lamps to clean and clean; some special places can also choose lamp.Coordination principle, lighting and the overall style of the room should be coordinated, and the same room of a variety of lamps and lanterns should maintain color coordination or style coordination. Such as wooden walls, wooden cabinets, wooden roof of the rectangular balcony, suitable for installing rectangular wooden lamps, equipped with iron watches, iron pipes, glass tables and chairs of the rectangular lobby, suitable for the installation of rectangular iron pipe material chandelier. It has a gold cabinet door handle and a gold light projection bedroom, suitable for lamps with gold decorations.Three, select energy-saving lamps from five aspects of checksAt present, the peak period of power consumption, energy-saving lamps become a good helper. But there are many kinds ofenergy-saving lamps on the market, and people know little about their service life and light color index. At the recently concluded lighting fixtures exhibition,Panasonic, PHILPS, OPPLE, Ou Shilang and other energy-saving lamps, well-known brands are displaying the latest technology of energy-saving lamps. OPPLE for the first time the color (similar to sunlight degree) onto the real booth, the scene experts told reporters that the color is not good lighting will not only make up partial color, but also easy to cause blindness in children. Experts have suggested that the choice of quality energy-saving lamps can be checked from 5 aspects.1. colorThe reduction of light to objects. Good color rendering means that objects in this light are closer to the color of daylight at noon. Should choose three primary color water coated phosphor tube, can filter out more ultraviolet light, its long life, high color, than ordinary fluorescent lamp brightness increased by 30%, the color is as high as 80.2. rectifierThe current rectifier has two kinds of electronic rectifier and inductance rectifier. Compared with the traditional inductance rectifier, electronic rectifier starting time, stroboscopic less, thus eliminating the power loss and glare, no longer let rectifier "whining" sound (loss characteristics), can save about 30%, but also better protect eyesight.3. lamp face mask materialAt present, energy-saving lamps and lanterns are commonly used mask materials PMMA (polypropylene), PVC (polyethylene) and glass. By comparison, PMMA material has high transmittance, light body, UV and anti-aging ability, good heat resistance; PVC transmittance is poor; glass material is too thick, and does not have UV protection ability.4. service lifeGB requirements, energy-saving lamps must reach 5000 hours of life, the purchase should be carefully examined.5., looking for brandProfessionals remind consumers to buy energy-saving lamps to choose well-known brands, and confirm that the product packaging integrity, signs complete. The outer packing usually illustrates the life, color rendering and correct installation position of the energy-saving lamp. After opening the packaging, energy-saving lamps should also have some of the necessary signs, mainly: power supply voltage, frequency, rated power, the manufacturer's name and trademark.Four, select lighting tipsRecently, several consumers have proposed that they have seen a great variety of lights in the market. They are very beautiful, but it is not suitable to buy them at home. I hope I can get some professional advice. At present, Jiezhuang designers toprovide a few choices, lighting tips.Lighting is an important part of modern family decoration, through the light color, shape and many lights combination, can foil different room atmosphere, for room decoration add color. When choosing, you'd better consider the basic lighting of the lamp. For example, the living room is my pick sites for creating a warm atmosphere of warmth, you can choose bright, beautiful lamps, chandeliers, ceiling lamps with lamp based; the living room is the rest of the nest, romantic, gentle is the theme gives it, select soft and strong decorative lamps can foil a warm and elegant atmosphere for your bedroom, desk lamp, wall lamp, floor lamp in general; children room requirements of colorful, changeable style lamps, creating a lively and safe space for children, suggested the use of chandeliers, ceiling lamps. Toilet should choose simple and waterproof function of lamps and lanterns, generally with wall lamp, ceiling light mainly; the kitchen should choose concise modelling, easy to wipe, easy to clean lamps and lanterns.Lighting materials should be in harmony with the overall decoration style. For example, crystal lamp brilliant contrast luxurious style; gilded iron bastions lamp display simple and elegant style; natural lighting material gives a natural feeling. You can decorate with your own preferences for materials. In the color matching, pay attention to the light and color of each other, through the combination of lights to create different seasons require warm and cold tones.Five, how to choose fluorescent lamps1, select good reputation of commercial enterprises, buy brand awareness, and higher market share of products produced by enterprises;2, check the product logo is complete,The marking of regular products shall be as follows: trademark and factory name, type, specification, rated voltage, frequency and power;3, lamps and lanterns power line should have the the Great Wall mark, the conductor cross section area should be more than (equal to) 0.5mm (square millimeter);4, the lamp body can not be exposed, light bulb into the lamp holder, fingers should not touch the live metal lamp holder.How to use fluorescent lamps:1, after the purchase of lamps, should be in accordance with the provisions of the instructions to install and use lamps;2, found that both ends of the tube red, fluorescent tube flickering, should replace the lamp tube in time, to prevent the occurrence of ballast burning;3, the use of adjustable lamps, should be adjusted within the specified range;4, lamps and lanterns do not hang other objects.Six, lighting selection and layoutOpen spaces allow the restaurant and the kitchen to look at each other.Home Furnishing layout smart lighting aware of the importance, often with beautiful shape, lighting lighting effects proper environment for Home Furnishing touch. Here to tell you a little about the lighting of the purchase and layout of small skills, I hope to help you create a home warm effect.The lights reflect Yokado -- living room lightingThe living room to a bright chandelier or Xidingdeng generous as the main light, collocation a variety of other auxiliary lighting, such as wall lamp, lamp, lamp etc..On the main lighting, if the living room height of more than 3.5m above the living room, can choose high grade, size slightly larger chandelier or ceiling lamps: if the height of about 3M, to use the mid-range luxury chandelier: Storey below 2.5m, to use the mid-range of decorative ceiling lamps or without main lamp.In addition, an independent desk lamp or floor lamp is placed at one end of the sofa to allow the direct light to scatter throughout the sitting area for conversation or browsing. Can also be placed in the wall appropriate shape unique wall lamp, can make the wall shining. If there are murals, display cabinets, etc., you can set invisible spotlights to be dotted. Put a miniature incandescent illumination in the television, canweaken the hall light and dark contrast, is conducive to the protection of eyesight.The lamp warms the heart -- restaurant lightingThe main focus of the family restaurant lighting is the table. Lighting chandelier hanging generally available, in order to achieve the effect, the chandelier can not be installed too high, can be in the meal's eye level. Rectangular table, the installation of two long oval pendant or pendant chandeliers have light and dark regulator and the lifting function, to double as other work with the Chinese pay attention to color, smell and taste, shape, often need some warm colors bright, and enjoy Western-style food, if the light is dark slightly softer, you can create a romantic atmosphere.The dining room ceiling and walls must have adequate lighting, otherwise it will affect the appetite, can use the auxiliary lighting lamp or wall lamp.Light watch House -- study lightingThe study environment should be gentle and quiet, concise and lively. The light is preferably irradiated from the upper end of the left shoulder, or a desk lamp with higher brightness and no glare is arranged in front of the desk. Table lamp for special study should adopt art table lamp, such as rotary table lamp or light regulating art table lamp, so that light can be directly illuminated on the desk. Generally, the utility model does not need to be fully used, and the invisible lamp is arranged on the bookcase for the convenience of retrieval.If a "multi-purpose room" "study", it is appropriate to use semi closed, opaque metal work lights, the light can be concentrated on the desktop, not only to meet the needs of the work plane, and does not affect other indoor activities. If you read in the chair, sofa, it is best to use adjustable direction and height of the floor lamp.Lighting dreams - bedroom lightingBedrooms are room for rest and sleep, and require better privacy. The light is soft and there should be no thorn in the eye to make it easier for people to sleep. Dressing and make-up require uniform bright light.Can choose the ceiling light is not strong for basic lighting, placed in the middle wall and ceiling; the mirror can be installed near the wall; the bed with bedside lamp, in addition to the common lamp,The utility model relates to a modern metal lamp whose base is fixed on the bed supporting plate and can adjust the angle of the lamp cap, and is beautiful and practical.Kitchen cooking -- kitchen lightingThe lamps and lanterns used in the kitchen are usually waterproof, smoke free and easy to clean. Generally, an embedded or semi embedded astigmatic ceiling lamp is arranged above the operating table, and the mask is embedded with transparent glass or transparent plastic, so that the ceilingis concise, and the trouble caused by dust and oil pollution is reduced.Generally set above the stove hood, hood hidden inside a small incandescent lamp for lighting the stove. If the kitchen doubles as a dining room, a single cover, a single fire, a lift or a single, multi chandelier can be placed above the dining table. Incandescent light bulbs should be adopted for light sources, and fluorescent lamps should not be used with cool colors.。
低浓度瓦斯氧化后冷热电联供方法
低浓度瓦斯氧化后冷热电联供方法兰波【摘要】为了提高我国低浓度抽采瓦斯和乏风瓦斯的利用率，提出一种将低浓度瓦斯氧化并利用余热进行冷热电联供方法。
该方法利用热逆流氧化技术实现对低浓度瓦斯高效氧化，抽取部分高温烟气生产高品位的蒸汽推动汽轮机发电，同时可从汽轮机抽取低压蒸汽，一部分用于供暖，一部分用于溴化锂吸收式制冷机制冷。
分析表明，该方法实现了对低浓度瓦斯的有效氧化，减少了温室气体排放，并对余热实现了梯级利用，大大提高了系统的热能利用率，具有良好的推广应用价值。
%To improve the utilization ratio of low⁃concentration mine gas and ventilation air methane( VAM) ,a combined cooling heating and power technology(CCHP) applied in low⁃concentration mine gas oxidization utilization was present in this paper.The method can oxidate mine gas efficiently by using thermal reverse⁃flow reactor,and extract part of high temperature gas to produce steam,drive tur⁃bine,and refrigerate.This technology can oxidize low⁃concentration gas efficiently,and achieves energy cascade utilization.The technolo⁃gy is worthy of popularization and application.【期刊名称】《中州煤炭》【年(卷),期】2016(050)008【总页数】4页(P34-37)【关键词】低浓度瓦斯氧化;冷热电联供;梯级利用【作者】兰波【作者单位】中煤科工集团重庆研究院有限公司，重庆 400037【正文语种】中文【中图分类】TD712.67研究表明，甲烷是一种温室气体，以100年计，甲烷温室效应约为二氧化碳的21倍［1］。
科技英语(电子类)(第三版)第二部分(第八课)
Overview of Electronic Technology
Development of electronic technology
The history and evolution of electronic technology, including the significant inventions and advancements that have shaped its developysis
Assigned readings from technical documents and reports will be used to improve reading comprehension.
Writing practice
Students will write technical reports and emails in English to improve their writing skills.
02 03
Passive elements
A detailed explanation of passive elements such as resistors, capacitors, and inductors, including their functions, characteristics, and applications.
Science and Technology English (Electronic) (Third Edition) Part 2 (Lesson 8)
电动车和柴油车的比较英语作文
电动车和柴油车的比较英语作文Comparison between Electric Vehicles and Diesel Cars.In recent years, the transportation sector haswitnessed a significant shift towards sustainable and environmentally friendly modes of travel. Electric vehicles (EVs) have emerged as a popular alternative to traditional diesel cars, offering a range of advantages that are hardto ignore. This article aims to compare EVs and diesel cars, highlighting their respective features, environmental impacts, and economic considerations.Technology and Performance.Electric vehicles rely on batteries to store energy, which is then converted into mechanical energy to power the vehicle. These batteries can be charged at home or public charging stations, providing a clean and renewable sourceof energy. Diesel cars, on the other hand, use diesel fuelto power their engines, which produce emissions thatcontribute to air pollution.In terms of performance, EVs offer silent operation, smooth acceleration, and low maintenance costs. The lack of a combustion engine means fewer moving parts and less wear and tear. Diesel cars, although still popular, require regular maintenance, including oil changes, filter replacements, and engine tune-ups.Environmental Impacts.The environmental benefits of EVs are numerous. Firstly, they emit no tailpipe emissions, meaning they contribute zero greenhouse gas emissions during operation. This is a crucial factor in the fight against climate change, as greenhouse gas emissions from transportation account for a significant portion of global emissions.Secondly, EVs reduce the dependency on fossil fuels, which are a non-renewable resource. The more EVs we have on the road, the less demand there will be for diesel fuel, potentially leading to a decrease in fossil fuel prices anda reduction in the extraction and refining processes that are often environmentally destructive.Diesel cars, on the other hand, emit harmful gases such as carbon dioxide, nitrogen oxides, and particulate matter. These emissions contribute to air pollution, respiratory problems, and climate change.Economic Considerations.The initial cost of an EV is typically higher than a diesel car. This is due to the cost of the batteries, which make up a significant portion of the vehicle's price. However, the long-term costs of ownership can be lower for EVs. Electricity is generally cheaper than diesel fuel, and maintenance costs are reduced due to the simpler mechanical structure of EVs.Additionally, governments around the world are offering incentives to encourage the adoption of EVs. These incentives can include tax credits, rebates, and exemptions from certain fees. As the technology improves and thedemand for EVs increases, prices are expected to drop, making them more accessible to a wider range of consumers.Conclusion.Electric vehicles offer a range of advantages over diesel cars, particularly in terms of environmental sustainability and long-term cost savings. While theinitial purchase price may be higher, the reduced operating costs and environmental benefits make EVs a viable and attractive option for many consumers. As the technology continues to improve and charging infrastructure becomes more widespread, the future of transportation looks increasingly electric.。
核电行业的英文介绍
核电行业的英文介绍Nuclear Power Industry: An IntroductionIntroductionThe nuclear power industry plays a crucial role in meeting the increasing demand for electricity worldwide. As concerns about fossil fuel depletion and environmental impact grow, nuclear power has emerged as a viable alternative. This article provides an introduction to the nuclear power industry, highlighting its importance, history, benefits, and challenges.I. Importance of the Nuclear Power IndustryA. Meeting Energy Demand: Nuclear power plants provide a significant share of the world's electricity. They contribute to a stable and reliable energy supply, reducing the dependence on fossil fuels.B. Carbon-Free Energy: Nuclear energy is a low-carbon form of power generation, contributing to the reduction of greenhouse gas emissions. It plays a vital role in mitigating climate change.II. History of Nuclear PowerA. Early Developments: The concept of nuclear power emerged in the early 20th century, with breakthroughs in understanding atomic structure and energy. Researchers like Marie Curie and Albert Einstein laid the foundation for nuclear science.B. Manhattan Project: During World War II, the Manhattan Project brought together scientists to develop the first nuclear weapons. This projectmarked a significant turning point in the advancement of nuclear power technology.C. Commercial Use: The first commercial nuclear power plant, Calder Hall, began operation in the United Kingdom in 1956. It paved the way for the expansion of nuclear power globally.III. Benefits of Nuclear PowerA. Clean Energy: Nuclear power generates electricity without emitting greenhouse gases, making it a vital tool for combating climate change. It significantly reduces air pollution and its associated health risks.B. Energy Efficiency: Nuclear reactors produce a large amount of electricity from a small amount of fuel. This efficiency ensures the optimal use of resources and reduces the reliance on imported energy sources.C. Resource Availability: Uranium, the primary fuel for nuclear power, is abundant in comparison to fossil fuels. It provides a long-term energy solution with reduced supply chain risks.D. Baseload Power: Nuclear power plants can operate continuously for extended periods, providing a stable flow of electricity to the grid. They offer a reliable source of baseload power, complementing intermittent renewable energy sources.IV. Challenges in the Nuclear Power IndustryA. Safety Concerns: The industry faces significant safety challenges due to the potential risks associated with reactor accidents, spent fuel storage,and waste disposal. The Fukushima Daiichi nuclear disaster in 2011 highlighted the need for strict safety regulations.B. Nuclear Waste: Proper disposal of nuclear waste remains a major challenge. Developing secure long-term storage solutions is crucial to address public concerns about radioactive materials.C. High Initial Costs: The construction and commissioning of nuclear power plants require significant upfront investment. Initial costs, including safety measures and regulatory compliance, can be substantial.D. Public Perception: Nuclear power often faces public skepticism and opposition due to safety concerns, waste management issues, and the potential for nuclear weapons proliferation. Effective communication and community engagement are necessary to build public trust.ConclusionIn conclusion, the nuclear power industry has emerged as a vital component of the global energy landscape. It offers clean and efficient electricity generation while reducing greenhouse gas emissions. Despite challenges related to safety, waste management, and public perception, nuclear power remains an essential source of reliable and low-carbon energy for the future. As technology advances and safety measures improve, the nuclear power industry continues to evolve and contribute to the world's sustainable energy goals.。
反激的典型波形
反激变换器的例子Analysis of basic waveforms基本波形分析The analysis of the basic waveforms will be done on a simula ted example of a flyback converter operating in discontinuous cond uction mode. Typical drain-source voltage waveform of the primary side switch is shown in Fig. 16.在电感电流断续模式下运行的反激变换器的典型一次侧漏源极开关电压波形见图１６。
Fig. 16 Typical drain-source voltage of the MOSFET in a flyback 图１６反激变换器的典型漏源极电压These drain-source voltage waveforms can be theoretically distin guished into typical elements. Different physical phenomena influence the waveform at given time interval. Fig. 17 and Tab. 4 demo nstrate the main elements of the voltage waveform. The superposit ion of all these elements results in a typical drain-source voltage s hown in Fig. 16.这些漏源极电压波形能用典型的理论来描述。
各个时间段有不同物理现象影响这些波形。
图１７和平台４描述了电压波形的主要原理。
把这些原理按时序整合呈现出图１６所示的典型漏源极电压。
国开形成性考核04008《理工英语(4)》单元自测(7)试题及答案
国开形成性考核《理工英语(4)》单元自测(7)试题及答案（课程ID：04008，整套相同，如遇顺序不同，Ctrl+F查找，祝同学们取得优异成绩！）题目1、（A）people are no longer worried about whether their food is safe or not （A）they enjoy a better life.【A】：Only if……can【B】：If only ……can【C】：What if……can题目2、—Do you eat porridge every day？—（B） .【A】：Porridge is my favorite【B】：No, sometimes I’d have a cup of soybean milk, a boiled egg and a steamed bun for my breakfast【C】：I seldom eat fast food beca use it’ s rich in fat题目3、—I think the other reason can be identified from the industrialization of food production.—（C） .Some illegal traders care about nothing but making money. 【A】：That bothers me too【B】：I sincerely hope that the whole society pay much more attention to food safety【C】：Yes, you bet题目4、—So how can we buy safe food？—（C） .【A】：The higher the price, the safer the food【B】：We can plant vegetables and fruits by ourselves【C】：When we choose food, we must remember to check its tag, confirming whether the basic information is marked on it题目5、—What is U.S’s experience in food safety management？—（B） .【A】：U.S.do better in this point【B】：They are improving the legal system all the time and very strict in law enforcement【C】：Some illegal traders care about nothing but making money题目6、—What would you like to have for breakfast？—（A） .Would you like to have a taste？【A】：Twisted cruller, I bought it this morning【B】：I already had my breakfast【C】：Breakfast is the most important meal of the day题目7、Animal farming （B）about half of all human-caused greenhouse gases.【A】：count for【B】：accounts for【C】：count on题目8、I am really （A）by fresh ingredients, intricate cooking and diverse traditions of Chinese food.【A】：fascinated【B】：fabricate【C】：fancy题目9、Modern Meadow is a startup that engineers tissues to create lab-grown （A）meat.【A】：edible【B】：editable【C】：edify题目10、Some illegal traders care about nothing but （B） .【A】：to make money【B】：making money【C】：made money题目11、The problem is uneven distribution, （C）870 million suffering from hunger.【A】：left【B】：to leave【C】：leaving题目12、The technology has several advantages （B）earlier attempts to engineer meat in vitro .【A】：in comparison of【B】：in comparison to【C】：compare with题目13、They should never try to pursue profit （C）health and life of people.【A】：in terms of【B】：at sight of【C】：at the expense of题目14、This, they argue, will be essential to （B）the needs of a booming population in decades to come and avoiding starvation.【A】：meet【B】：meeting【C】：met题目15、You can have eggs （B）or hard-boiled.【A】：frying【B】：fried【C】：have fried题目16、阅读理解：阅读下面的短文, 根据文章内容从A、B、C 三个选项中选出一个最佳选项。
新旧对比英语作文模板
新旧对比英语作文模板Title: A Comparison of Old and New in English Writing。
Introduction。
When it comes to comparing the old and the new, there are many aspects to consider. In the realm of English writing, the contrast between traditional and modern styles, techniques, and themes is particularly interesting. In this essay, we will explore the differences between old and new English writing, examining how they have evolved over time and considering the impact of these changes.Old English Writing。
Old English writing refers to the literature and language used in the early medieval period, from the 5th century to the 11th century. This era is characterized by the use of the runic alphabet, which was later replaced by the Latin alphabet. Old English writing is known for its complex grammar, rich vocabulary, and poetic forms such as alliteration and kennings. The content of Old English writing often focused on themes of heroism, loyalty, and the struggle between good and evil, as seen in epic poems like Beowulf.New English Writing。
电缆线端面火蔓延速率估算
电缆线端面火蔓延速率估算尚琪霞【摘要】This paper introduces the way to trace the cause of fire through certain chemical factory,and based on the results of on-spot observations.In this paper,the fire spread time was computed theoretically and tested to prove its correctiveness.%根据某化工厂火灾现场勘验结果,运用火灾事故调查方法,推断火灾事故发生的原因。
在分析电缆起火原因时,引用计算火蔓延速率的半经验公式,并且根据实际对公式的参数进行修订,对高压电缆火灾的蔓延时间进行理论上的推导,最后用火灾实际发生时间来检验计算结果,以进一步佐证火灾原因调查的正确性。
【期刊名称】《武警学院学报》【年(卷),期】2011(027)010【总页数】3页(P16-18)【关键词】火灾调查;电缆火灾;火蔓延速率【作者】尚琪霞【作者单位】晋城市消防支队,山西晋城048026【正文语种】中文【中图分类】X928.7火蔓延速率是指在水平面内向外延伸的火的相对运动，表示为火焰总周长的增长速率，也表示为火焰前锋向前蔓延的速率，或者表示为火焰面积的增长速率。
火蔓延特性受材料种类、含水率、几何尺寸、空间方位以及环境因素的影响，特别是来流特性对火蔓延状况的影响尤为显著。
火蔓延速率是影响火灾发展过程的一个重要参数。
因此，测量与计算固体可燃物火蔓延的机理和规律十分必要。
笔者通过对某化工厂高压电缆起火原因的调查，对高压电缆火灾的蔓延时间进行理论计算，与火灾实际发生时间进行对比，以佐证火灾原因调查的正确性。
1 火灾基本情况及起火点的认定2008年7月11日21时30分许，某化工厂发生火灾。
火灾烧毁动力电缆、控制电缆、梯形玻璃钢电缆桥架和变换区工艺流程管道等，过火面积达400余平方米，未造成人员伤亡。