007Gas adsorption on graphene doped with B,N,Al,and S_A theoretical study

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第八届国际凝聚态理论与计算材料学会议

大会将请专家对以下领域作专题性的特邀报告:
(1). 凝聚态物理的最新进展:
A. 自旋电子学
B. 纳米材料
C. 固体量子信息和计算
D. 玻色－爱因斯坦凝聚
E. 强关联电子系统
F. 高温超导
G. 量子霍尔效应
H. 磁学
I 表面和界面
J. 半导体物理
K. 低维凝聚态物理
L. 介观物理
M. 软凝聚态物质
N. 生物物理
structure Metallic Phases in Solid Germane (GeH4) under Pressure 锗烷在
压力下的金属相
11:45 -12:15
12:15 -13:00
午餐
张振宇橡树岭国家实验室
柳百新
清华大学
林海青香港中文大学牛谦美国德克萨斯大学
7 月 16 日
凝聚态理论专题邀请报告 I 主持人：谢心澄地点：芙蓉厅
14:30 -14:55 14:55 -15:20 15:20 -15:45 15:45 -16:10 16:10 -16:35 16:35 -16:50
7 月 16 日
Manipulating Magnetization States of Nanostructures Two-spin decoherence in semiconductor quantum dots
稀磁半导体(Al,Cr)N 中的氮空位与高温铁磁性的第一原理研究
蒋青刘邦贵
吉林大学中科院物理所
15:20 -15:45 15:45 -16:10 16:10 -16:35
Theoretical and experimental studies of semiconductor dilute nitrides and devices

正溴丙烷已被美国环保署列为可接受替代品

工业清洗专家++======上海敏晨化工有限公司专业致力于：五金清洗、光学镜片、树脂溶剂、PCB 板清洗剂、带电设备清洗剂、汽配零件，不锈钢清洗，除油等行业的服务。

正溴丙烷已被美國環保署列為可接受替代品美國環保署於今年（2007年）5月30日公告將nPB （正溴丙烷，n-propyl bromide 或1-bromopropane ）列為金屬清洗、電子產品清洗及精密清洗的可接受替代品，可用來替代破壞臭氧層物質（ODS ）包括CFC-113和methyl chloroform 。

此法案自2007年7月30日起正式生效。

nPB 是一種有機溶劑，雖不可燃但有強烈的氣味，其化學式為C3H7Br ，化學文摘社的登記號碼（Chemical Abstracts Service Registry Number ，簡稱CASRN ）為106-94-5。

nPB 的主要用途是在脫脂及噴霧膠粘劑。

市場上含有n PB 的品牌包括Abzol 、Ensolv 及Solvon Cleaners 、Pow-R-Wash NR Contact Cleaner 、Superklean Flux Remover 22311及LPS NoFlash NU Electro Contect Cleaner aerosols 、Whisper Spray 、以及消防用途的Fire Retardant Soft Seam 6460 Adhesivers 。

美國環保署最早於2003年6月針對nPB 的使用公告了一項草案，為決定nPB 可以被SNAP （Significant New Alternative Policy ）Program 列為可接受的ODS 替代品，美國環保署一直在評估nPB 對人體健康與環境的傷害與衝擊。

自2003年之後，愈來愈多有關nPB 對人類健康影響的暴露數據和研究已成為可取得的資科。

考慮所有資料後，美國環保署認為和其他被SNAP Program 列為可接受的清洗替代品相比較，nPB 並不顯著提高整體對人類健康和環境的危害性。

Computational Investigation of Adsorption of Molecular Hydrogen on Lithium-Doped Corannulene

Computational Investigation of Adsorption of Molecular Hydrogen on Lithium-Doped CorannuleneY.Zhang,†L.G.Scanlon,‡M.A.Rottmayer,‡and P.B.Balbuena*,†Department of Chemical Engineering,Texas A&M Uni V ersity,College Station,Texas77843,and Air Force Research Laboratory,Energy Storage&Thermal Sciences Branch,Wright-Patterson Air Force Base,Ohio45433Recei V ed:June24,2006;In Final Form:August14,2006Density functional theory and classical molecular dynamics simulations are used to investigate the prospectof lithium-doped corannulene as adsorbent material for H2gas.Potential energy surface scans at the level ofB3LYP/6-311G(d,p)show an enhanced interaction of molecular hydrogen with lithium-atom-doped corannulenecomplexes with respect to that found in undoped corannulene.MP2(FC)/6-31G(d,p)optimizations of4H2-(Li2-C20H10)yield H2binding energies of-1.48kcal/mol for the H2-Li interaction and-0.92kcal/mol forthe H2-C interaction,whereas values of-0.94and-0.83kcal/mol were reported(J.Phys.Chem.B2006,110,7688-7694)for physisorption of H2on the concave and the convex side of corannulene using MP2-(full)/6-31G(d),respectively.Classical molecular dynamics simulations predict hydrogen uptakes in Li-dopedcorannulene assemblies that are significantly enhanced with respect to that found in undoped molecules,andthe hydrogen uptake ability is dependent on the concentration of lithium dopant.For the Li6-C20H10complex,a hydrogen uptake of4.58wt%at300K and230bar is obtained when the adsorbent molecules are arrangedin stack configurations separated by6.5Å,and with interlayer distances of10Å,hydrogen uptake reaches6.5wt%at300K and215bar.1.IntroductionHydrogen has been proposed as a potential clean fuel,1but in order to be commercially employed,it is critical to develop compact,low-cost,and safe storage materials.The U.S.Depart-ment of Energy(DOE)set up the criteria of storing6.5wt% of hydrogen(density of62.5Kg/m3)for an ideal energy hydro-gen carrier.Other than storage in high-pressure tanks as gas or cryogenic hydrogen,different advanced hydrogen storage mater-ials have been extensively studied,including metal hydrides (MHs),2-5carbon-based,6-13and organometallic materials.14-19 The main mechanism of hydrogen adsorption on metal hydrides is chemisorption,and thus the desorption of hydrogen occurs at temperatures above500K and/or the hydrogen uptake capacity is low,about2wt%,due to the presence of heavy metals.2-5Hydrogen adsorption in carbon-based and organo-metallic materials is caused by anometallic materials14-19possess a low density,high surface area,and are porous materials.Hydrogen adsorption on organometallic materials shows about4.5wt%at77K and1wt%at room temperature and20bar.18,20The low hydrogen uptake at room temperature is the main disadvantage for the use of organome-tallic materials as adsorbents.With the advent of nanotechnol-ogy,carbon-based materials,including nanotubes,nanofibers, and activated carbon materials,have been analyzed experimen-tally and theoretically.6-13,21-23However,as a result of weak interactions between H2and pure carbon,these materials do not show sufficient storage capacity for commercial use under room temperature working conditions.Since Chen et al.24reported that alkali-metal-doped carbon nanotubes exhibit remarkable hydrogen uptake,a great deal of experimental and theoretical work has been done to investigate the hydrogen adsorption in metal-doped carbon materials.25-31 These studies showed that charge transfer from the alkali metal to these carbon materials polarize hydrogen molecules.As a result,a charge-induced dipole moment enhances the adsorption of hydrogen at ambient conditions.Besides,doping also increases the space to bind additional amounts of H2.30We have recently reported hydrogen adsorption on corannu-lene,a bowl-shaped molecule32with higher electron density in peripheral-carbon atoms than in inner-carbon atoms.33MP2 calculations yielded binding energies in the range-0.94to -0.83kcal/mol between a single hydrogen molecule andcorannulene,depending on the adsorption site.33Molecular dynamics(MD)simulations of crystalline corannulene predicted about0.79wt%of H2at72bar at273K and0.68wt%at300 K,in very good agreement with experimental results.33On the basis of MD simulations of corannulene stacks with different interlayer separations,we observed that the main factors that affect the hydrogen uptake capacity include the pressure applied to the system,temperature of adsorption,and the available space in the adsorbent assembly.For corannulene molecules arranged in stacks,it was observed that,as the interlayer distance(ILD) increases,the hydrogen uptake increases significantly.Thus,the adsorption of an alkali metal may enhance H2storage,not only due to the induction of dipole moments but also because of the generation of additional available space for H2storage. Experimentally,ball milling has been proved to effectively increase the lithium doping concentration in carbon materials, and this technique is ready to be extended to industrial scales.34 Kang35found the stable complex of pyrene-Li4where the ratio of Li to C is1:4.Deng et al.30found that the most stable ratio*Corresponding author.E-mail:balbuena@.†Department of Chemical Engineering,Texas A&M University.‡Air Force Research Laboratory,Energy Storage&Thermal SciencesBranch,Wright-Patterson Air Force Base.22532J.Phys.Chem.B2006,110,22532-2254110.1021/jp063963e CCC:$33.50©2006American Chemical SocietyPublished on Web10/13/2006of Li:C is1:6and1:8for Li-graphite intercalation compound (Li-GIC)at its equilibrium interlayer distance,while it is1:3 for Li-pillared graphene sheet(Li-PGS)for interlayer separa-tions greater than8Å.In this paper,we report ab initio and density functional theory(DFT)studies of the doping of lithium atoms to the corannulene molecule as well as on its interactions with H2.We also analyze the effect that doping of Li atoms to corannulene has on H2uptake capacity at finite temperatures and pressures using classical MD simulations.We investigate two types of structures,one with six lithium atoms doped on a single corannulene molecule and the other with five lithium atoms,which leads to Li to C ratios between1:3and1:4, consistent with results from other groups.30,35putational Methods2.1.Ab Initio and DFT Calculations.The Gaussian03 package36was used to undertake the molecular orbital theory calculations.Previous theoretical studies on corannulene indi-cated that a hybrid DFT method combined with double- plus polarization basis sets would well reproduce the structural parameters of corannulene37,38and protonation and lithiumcation binding on corannulene.32,39In this paper,we use B3LYP/ 6-31g(d,p)for geometry optimization of lithium-atom-doped corannulene complexes and B3LYP/6-311g(d,p)for potential energy surface scans.The optimized geometries are followed by frequency calculations to prove that the stationary points are local minima and find the zero point energy corrections. Single point calculations and full optimizations using second-order Mo¨ller-Plesset perturbation theory(MP2)with the6-31G-(d,p)basis set are performed to obtain more accurate binding energies accounting for weak van der Waals forces that are responsible for the H2/corannulene interaction based on phys-isorption.2.2.Classical MD Simulations.The derivation of the force fields for H2-corannulene interactions was reported previ-ously.33Lennard-Jones(LJ)parameters were derived using the LJ parameters for the Li atom,D Li-Li)0.025kcal/mol,and x Li-Li)2.451Å,40corresponding to the form:These parameters and eq1were used to generate a new set of parameters according to the equivalent formyielding LiLi)0.0275kcal/mol andσLiLi) 2.18Å.The Lorentz-Berthelot mixing rules were used to obtain the LJ cross parameters Li-H)0.0432kcal/mol andσLi-H)2.57Å.For the dipole-induced interaction,the dipole moment of the Li3-C20H10-Li2complex(3.856D)calculated at the level of B3LYP/6-311G(d,p)and the Li polarizability of2.43×10-23 cm3(ref41)were used to define an average pair interaction calculated as:The dipole-induced interaction between Li and H2(equation3) was added to eq2to generate new data using the nonbonded interaction parameters Li-H)0.0432kcal/mol andσLi-H) 2.57Å,and a new fitting of these data to the form of the LJ eq 2yielded Li-H)0.9kcal/mol andσLi-H)2Å,which are the parameters used in the MD simulations.The DL_POLY program,42version2.14,was used for all MD simulations.A cutoff value of10Åwas used for nonbonded interactions,and periodic boundary conditions in three dimen-sions were applied to the simulation cell.The simulations were run in the canonical NVT ensemble at temperatures of273K and300K and pressures up to250bar.Details of the assembled system are provided in the Results and Discussion Section.The total simulation time for each P and T is800ps,with300ps for the equilibration period and500ps for the production period. The evaluations of H2uptake are based on the500ps production period.3.Results and Discussion3.1.Doping of Li Atoms to Corannulene.Corannulene isa bowl-shape molecule with C5V symmetry.Figure1shows the structure of corannulene optimized at the level of B3LYP/6-311G(d,p).There are three types of carbon atoms:the outmost 10carbons bonded to one hydrogen each are named as“rim”carbons(C r),the innermost five carbons on the five-membered ring as“hub”carbons(C h),while the remaining five carbons connecting between the rim and hub carbon atoms are designated as“bridge”carbons(C b).The calculation shows that rim carbon atoms possess higher electron density than hub and bridge carbon atoms,thus the dipole vector would point toward the five-membered ring.The calculated dipole moment of corannulene is2.18D,which is close to the experimental data of2.07D.43The structural information and Mulliken charge distribution of corannulene are shown in Table1.Recent DFT studies35of Li-aromatic sandwich compounds, R-nLi-R,where R is benzene,naphthalene,or pyrene,reported that the Li atom was preferentially adsorbed over the six-membered ring instead of over individual or pairs of C atoms. For a single Li ion,it was found that the Li cation was bounded on the convex side over a six-membered ring of corannulene at the level of B3LYP/6-311G(d,p)//B3LYP/6-31G(d,p).32The data in Table2indicate that complexation of a Li ion at the convex side is more stable than at the concave side,which is in agreement with the results of Frash et al.,32whereas,for the Li atom,complexation at the concave side is more stable(by1.2 kcal/mol)than at the convex side.E vdw )DIJ{-2[x IJ x]6+[x IJ x]12}(1)E vdw )4 {[σIJr]12-[σIJ r]6}(2)Γh ij )-7759.74r6meV(3)Figure1.Optimized structure of corannulene at the level of B3LYP/6-311G(d,p).TABLE1:DFT(B3LYP/6-311G(d,p))Structural Parametersand Mulliken Charge Distribution in Corannulene aatom charge atom pair bond distance(Å)angle(deg)C h-0.04C h-C h 1.42C h-C h-C b122.88C b0.00C h-C b 1.38C h-C b-C r114.43C r-0.07C b-C r 1.45C b-C r-C r121.96H+0.09C r-C r 1.40C r-C b-C r129.78a The atomic charges are average values.Adsorption of Molecular H on Lithium-Doped Corannulene J.Phys.Chem.B,Vol.110,No.45,200622533The Mulliken charges on the various atoms (labels as in Figure 1)shown in Table 2suggest that the higher charge of the Li cation may be the reason for the stronger binding to the corannulene molecule.Multiple Li atoms can be adsorbed either at the concave or at the convex side.Figure 2shows attachment of five Li atoms on corannulene at the level of B3LYP/6-31G(d,p).Considering the effect of charge transfer from Li to C atoms and thus the repulsion between two positively charged lithium atoms,the initial geometries were arranged with Li atoms over the outer six-membered rings on either side.In the initial configuration,all five Li atoms were located at the same side (either convex or concave)of the corannulene molecule,and the optimized structure resulted always with the five Li atoms attached to the concave side,over the six-membered rings,as shown in Figure 2a.Thus,when the optimization was started locating the Li atoms over the convex side,there was an inversion of curvature of the corannulene molecule,in agreement with the tendency shown in Table 2for a single Li atom.Similarly,when the initial configuration contains two Li atoms on one side and three on the other side,the energetically favorable optimized conforma-tions contain more Li atoms on the concave side,that is,three Li atoms on the concave side and the other two Li atoms on the convex side (Figure 2b);this conformation has lower energy than that in Figure 2a by minimizing repulsion effects.Frequency calculations indicate that both complexes in Figure 2are local minima.Comparison of the respective energies is shown in Table 3,along with related structural information.The Li 5-C 20H 10and Li 3-C 20H 10-Li 2complexes have σV symmetry,as shown in Figure 2.Table 3illustrates that there is charge transfer from Li atoms to corannulene molecules,resulting in positive charges on Li atoms of Li 5-C 20H 10and Li 3-C 20H 10-Li 2.Overall,the total charge on Li atoms in Li 3-C 20H 10-Li 2is higher than those in Li 5-C 20H 10.Thus,C atoms of corannulene are more negatively charged in the first complex,resulting in higher electrostatic interaction and shorter distances from Li atoms to six-membered rings of corannulene in Li 3-C 20H 10-Li 2than in Li 5-C 20H 10.Each of the three Li atoms (1Li,4Li,and 5Li)on the concave side of Li 3-C 20H 10-Li 2locate close to the center of a six-membered ring,whereas the two attached to the convex side of Li 3-C 20H 10-Li 2are closer to a six-membered ring than those on the concave side of Li 5-C 20H 10.The calculated energies show that Li 3-C 20H 10-Li 2is about 4kcal/mol more stable than Li 5-C 20H 10;the binding energy per Li atom is -23.91kcal/mol-Li in Li 3-C 20H 10-Li 2and -23.11kcal/mol-Li in Li 5-C 20H 10.The doping of six Li atoms on corannulene is illustrated in Figure 3,which shows four different combinations tested on the basis of the results obtained for complexes with five Li atoms.Figure 3a displays the complex Li 6-C 20H 10,where the first five Li atoms are doped over six-membered rings on the concave side,and the sixth lithium atom is in the center over these five Li atoms.Alternatively,with the sixth Li atom doped at the convex side,we obtain the Li 5-C 20H 10-Li complex (Figure 3b).Both Li 6-C 20H 10and Li 5-C 20H 10-Li have σV symmetry,with the atoms labeled 1Li and 6Li located on theTABLE 2:Structural and Energetic Properties and Mulliken Charges in Complexes of Corannulene with a Lithium Cation/Atom Attached to a Six-Membered Ring,Optimized at the B3LYP/6-31G(d,p)Levelcharges on atoms (e)complex with corannulene Li -C distance(Å)electronic energy(hartrees)binding energy (kcal/mol)Li C r C b C h Li +on the concave side 2.28-2.31-775.52514-47.50.44-0.120.12-0.03Li +on the convex side 2.29-2.44-775.52700-48.70.46-0.130.15-0.06Li on the concave side 2.22-2.25-775.68264-16.80.33-0.150.11-0.05Li on the convex side2.14-2.38-775.68073-15.60.31-0.160.17-0.08Figure 2.Optimized (B3LYP/6-31G(d,p))conformations of corannulene complexed with five Li atoms doped at different positions.(a)Five Li atoms doped at the concave side over six-membered rings,Li 5-C 20H 10.(b)Three lithium atoms doped at the concave side and two at the convex side over six-membered rings,Li 3-C 20H 10-Li 2.22534J.Phys.Chem.B,Vol.110,No.45,2006Zhang et al.symmetry plane.Another complex contains the first five Li atoms doped as in the complex Li 3-C 20H 10-Li 2,and the sixth Li atom is attached either to the concave or to the convex side over a six-membered ring,forming Li 4-C 20H 10-Li 2(Figure 3d)and Li 3-C 20H 10-Li 3(Figure 3c).These complexes are no longer symmetric after optimization.Frequency calculations on the optimized structures of these complexes also indicate they are local minima,except for Li 5-C 20H 10-Li,which is a saddle point.Table 4summarizes partial structural and energetic informa-tion.The most important difference is the negative charge over the Li atom on top of Li 6-C 20H 10,which may favor electrostatic Li -Li interactions,resulting in Li 6-C 20H 10being 9kcal/mol more stable than Li 3-C 20H 10-Li 3.The binding energies per mole of Li are -25.03and -23.53kcal/mol-Li for Li 6-C 20H 10and Li 3-C 20H 10-Li 3,respectively.The relatively large binding energies of the Li 6and Li 5complexes of corannulene might indicate stable Li adsorption on corannulene,with the ratio of Li:C between 1:4and 1:3.The lithium doping concentration is in agreement with results reported by other groups.30,353.2.Adsorption of H 2on Li-Doped Corannulene Com-plexes.3.2.1.Li 6-C 20H 10and Li 5-C 20H 10-Li.Adsorption of H 2is studied on the most stable complexes at each doping concentration,i.e.,on Li 6-C 20H 10and on Li 3-C 20H 10-Li 2.To obtain a qualitative comparison of the interaction strengths of H 2in corannulene and Li-doped corannulene,we computed a potential energy scan,as shown in Figure 4,which illustrates that no attractive interactions between hydrogen and the corannulene molecule are detected at this level of theory when a head-on H 2molecule approaches the corannulene moleculeTABLE 3:Li-Doped Corannulene Complexes:Structural Information and Electronic Energy (Ha)and Binding Energy (kcal/mol of Li)at the Level of B3LYP/6-31G(d,p)distance Li -C (Å)acomplex Li label (as shown in Figure 2)charge of Li(e)Li -C r Li -C bLi -C h Li 5-C 20H 1010.32 2.142.653.072,30.14 2.23,2.24 2.30,2.33 2.32,2.344,50.25 2.14,2.17 2.51,2.55 2.82,2.86Li 3-C 20H 10-Li 210.45 2.212.292.362,30.48 2.13,2.19 2.27,2.53 2.18,2.414,50.222.13,2.22 2.25,2.472.42,2.51electronic energy (Ha)zero point energy (Ha)binding energy (kcal/mol of Li)Li -7.49098C 20H 10-768.164830.23195Li 5-C 20H 10-805.803840.23366-23.11Li 3-C 20H 10-Li 2-805.810220.23260-23.91aWhen two values are shown,each one represents two pairs of the distance of Li -C in σv complexes.TABLE 4:Li -Corannulene Complexes:Structural Information,Electronic Energy (Ha),and Binding Energy Per Li Atom (kcal/mol-Li)at the Level of B3LYP/6-31G(d,p)adistance Li -C (Å)complex Li label (shown in Figure 3)Li charge Li -C r Li -C bLi -C h Li 6-C 20H 1010.22 2.16 2.673.162,30.31 2.19,2.20 2.27,2.31 2.34,2.364,50.26 2.14,2.18 2.55,2.64 2.97,3.026-0.23 5.08 4.76 4.55Li 5-C 20H 10-Li10.45 2.102.573.052,30.14 2.17,2.22 2.31,2.40 2.43,2.444,50.21 2.07,2.15 2.46,2.49 2.75,2.7960.51 2.152.422.25Li 4-C 20H 10-Li 210.26 2.22,2.28 2.33,2.45 2.44,2.5220.47 2.14,2.19 2.27,2.51 2.21,2.3330.45 2.12,2.13 2.36,2.43 2.24,2.3140.15 2.23,2.37 2.23,2.55 2.37,2.5150.05 2.18,2.18 2.51,2.52 2.81,2.8460.49 2.149,2.157 2.518,2.585 2.92,2.98Li 3-C 20H 10-Li 310.30 2.32,2.37 2.35,2.46 2.36,2.4220.45 2.17,2.22 2.31,2.50 2.21,2.3330.20 2.13,2.25 2.26,2.63 2.24,2.4640.15 2.17,2.28 2.29,2.54 2.50,2.6550.35 2.17,2.39 2.31,2.62 2.57,2.7560.392.17,2.17 2.40,2.412.29,2.32electronic energy(Ha)zero point energy(Ha)binding energy (kcal/mol-Li)Li -7.49098C 20H 10-768.164830.23195Li 6-C 20H 10-813.350080.23616-25.03Li 5-C 20H 10-Li -813.345990.23443-24.61Li 4-C 20H 10-Li 2-813.347630.23374-24.78Li 3-C 20H 10-Li 3-813.335680.23309-23.53aEach value in σv symmetry complexes,Li 6-C 20H 10and Li 5-C 20H 10-Li,represents two pairs of the distance of Li -C.Adsorption of Molecular H on Lithium-Doped Corannulene J.Phys.Chem.B,Vol.110,No.45,200622535along pathways a,b,c,and d (Figure 4).However,when H 2approaches Li 6-C 20H 10(pathway e)or Li 3-C 20H 10-Li 2(path-way f),a relatively strong attractive interaction between H 2and the Li atom -corannulene complex is observed.The strongest attraction appeared when the center of mass of the H 2molecule is at a distance of 2.47Åfrom the corresponding Li atom (Figure 5),yielding binding energies of -0.47and -2.06kcal/mol with Li 6-C 20H 10and Li 3-C 20H 10-Li 2,respectively.Figure 5shows the structures of H 2interacting with Li 6-C 20H 10and Li 3-C 20H 10-Li 2at the geometries corresponding to the minima on the potential surface curves of Figure 4.The separation of 2.47Å(Figure 5)corresponds to a distance of 2.10Å,shown in Figure 4,because that is the distance between the closest H atom and the corresponding Li atom;the difference between them is one-half of the calculated bond distance of H 2(0.74Å).To account for weak van der Waals forces that are responsible for the H 2/Li -corannulene complex interactions,we use second-order Moller -Plesset perturbation theory to determine the energy corresponding to such geometries using the 6-31G(d,p)basis set.The calculated MP2/6-31G(d,p)energies (single point calculations)are -1.83and -2.82kcal/mol for the H 2-Li 6-Figure 3.Optimized (B3LYP/6-31G(d,p))conformations of corannulene with six Li atoms.(a)Six Li atoms doped at the concave side,Li 6-C 20H 10.(b)Five Li atoms doped at the concave side and one at the convex side,Li 5-C 20H 10-Li.(c)Three Li atoms doped at the concave side and three at the convex side,Li 3-C 20H 10-Li 3.(d)Four Li atoms doped at the concave side and two at the convex side,Li 4-C 20H 10-Li 2.22536J.Phys.Chem.B,Vol.110,No.45,2006Zhang et al.C 20H 10system and H 2-Li 3-C 20H 10-Li 2,respectively.Recently,we reported binding energies of -0.94and -0.83kcal/mol for the physisorption of H 2on corannulene using MP2(full)/6-31G-(d)for H 2on the concave side and the convex side,respec-tively.33Thus,the H 2-Li interaction is stronger than that between H 2and C based on these binding energies.In the next section,we refine these estimates using optimizations with the MP2method.3.2.2.Li 2-C 20H 10.In this section,we analyze the most favorable hydrogen adsorption sites using Li 2-C 20H 10(Figure 6a),first with two hydrogen molecules on the convex side (Figure 6b)and then with two hydrogen molecules on the convex side and two hydrogen molecules on the concave side (a total of four H 2molecules,Figure 6c).The optimized configurations of these systems at the MP2(FC)/6-31G(d)level have a symmetry plane,and the two H 2molecules adsorbed on the convex side are located on that plane (Figure 6b and c),one molecule is adsorbed over the five-membered ring,and the other over a six-membered ring,and each of the lithium atoms is located over a six-membered ring.For the H 2molecule adsorbed over the five-membered ring,the distance between the closer H atom to hub carbons is in the range of 3.13-3.24Å,while the H 2molecule over the six-membered ring is closer to the pair of hub carbon atoms in the center,with a distance in the range of ∼3.18Å.Two additional H 2molecules adsorbed on the concave side (Figure 6c)adsorb on lithium atoms;the shortest H -Li distance is ∼2.12Å,significantly shorter than the distance between H 2molecules (on the convex side)and carbon atoms.The difference between adsorption distances on the various sites suggests that the Li atoms are the most favorable sites for hydrogen adsorption,which is confirmed by the calculated binding energies.For H 2adsorbed on the convex side (Figure 6b),a binding energy of -0.92kcal/mol-H 2is obtained.On the basis of the similar geometry of these two adsorbed H 2molecules in Figure 6b and c,we assume that the binding energy of these two H 2molecules are the same in the two cases,thus we infer that a binding energy of -1.48kcal/mol-H 2corresponds to the interaction between H 2(on the concave side)and a lithium atom.The energetic difference clearly shows that Li atoms are the favorable adsorption sites for H 2molecules,suggesting a mechanism of enhanced hydrogen adsorption on lithium-atom-doped corannulene systems.Another important feature in the Li-doped complexes of corannulene is the increase of the dipole moment.DFT predicts values of 5.39and 3.86D,respectively,for Li 6-C 20H 10and Li 3-C 20H 10-C 2,whereas the MP2calculation yields 3.47D for the Li 2-C 20H 10complex.The presence of this enhanced dipole in the molecule induces a dipole moment in the H 2molecules,which is taken into account to define the effective force field (Section 2.2)for molecular dynamics simulations discussed in the next section.3.3.Adsorption at Finite Temperatures and Pressures.3.3.1.Arrangement of Adsorbent Molecules.To investigate the available space and collective effects on H 2adsorption,we assume that lithium-doped corannulene molecules arrange in a stack configuration.In this case,we can adjust the interlayer and intermolecular distances (as defined below),performing analyses similar to those reported by other researchers using carbon nanotube bundles and graphite nanofibers.30,44-46Each MD simulation cell contains 16lithium-atom-doped corannulene molecules,with eight molecules in each layer located at the bottom of the cell.In the MD simulations,the dynamics of the adsorbent molecules is not included,thus the adsorbent mol-ecules are kept fixed in their initial positions and their distribution in each layer is determined by two parameters,the interlayer distance,ILD,and the intermolecular distance,IMD.The ILD is defined as the distance between two overlapped molecules and the IMD is the separation between the centers of two parallel molecules,as shown in Figure 7.The values of IMD and ILD were determined from DFT calculations discussed in the nextsection.Figure 4.Potential energy surface of H 2approaching corannulene and lithium-doped corannulene at the level of B3LYP/6-311G(d,p);in each curve,H 2approaches corannulene at:(a)the center five-membered ring at the concave side,(b)the center five-membered ring at the convex side,(c)the center of a six-membered ring at the concave side,(d)the center of a six-membered ring at the convex side,(e)the top Li atom in Li 6-C 20H 10(see Figure 3),(f)the Li atom on the convex side in Li 3-C 20H 10-Li 2(see Figure2).Figure 5.Structures corresponding to the minima in the potential energy scans:(a)Li 6-C 20H 10,(b)Li 3-C 20H 10-Li 2.Figure 6.Optimized configurations of H 2adsorption on Li 2-C 20H 10,with MP2(FC)/6-31G(d):(a)Li 2-C 20H 10;(b)2H 2-(Li 2-C 20H 10);(c)4H 2-(Li 2-C 20H 10).Figure 7.Definition of interlayer distance (ILD)and intermolecular distance (IMD).Adsorption of Molecular H on Lithium-Doped Corannulene J.Phys.Chem.B,Vol.110,No.45,2006225373.3.2.Estimation of the IMD and ILD Parameters.DFT partial optimizations at the level of B3LYP/6-311G(d,p)are performed for the characterization of the ILD and IMD distances in dimers of Li 6-C 20H 10,as shown in Figure 7.To determine the optimum ILD value,only the z coordinates of the dimer are allowed to change,whereas only the x coordinates of the dimer are allowed to change to investigate the optimum IMD value.The results are 11.4Åfor the IMD and 6.5Åfor the ILD.In our MD simulations,the IMD is fixed to 11.0Åfor all the adsorbent systems,and additional values of ILD of 8.0and 10.0Åare used for a simple stack of two different lithium-doped corannulene systems.Such a system is chosen to investigate the potential H 2uptake capacity,assuming thatsubstitution of H with bulky alkyl function groups to the rim carbons or bridging of lithium-atom-doped corannulene mol-ecules might be used to increase the ILD.3.3.3.Hydrogen Adsorption on Lithium-Doped Corannulene.Figure 8shows the predicted H 2uptake at 273and 300K and various ILD for Li 6C 20H 10as a function of H 2pressure.Overall,the MD simulations predict:(1)at all the conditions studied,the H 2uptake is higher than 2wt %;(2)the H 2uptake at a given ILD and temperature is almost linear with the increase of pressure;(3)adsorption decreases as temperature increases;(4)increasing ILD while keeping the same T and P significantly increases the H 2uptake,and the change is especially notorious increasing the ILD from 8.0to 10.0Å.At the estimated equilibrium separation ILD of 6.5Å,the predicted H 2uptake values are 2.75-5.08wt %at 70and 225bar at 273K,whereas at 300K,the values are reduced to 2.38-4.58wt %at 75and 230bar,respectively (Figure 8).Thus,according to the projection,the H 2uptake at an ILD of 6.5Åwould reach 6.5wt %at 300K and 315bar.Parts c -f of Figure 8illustrate that the rate of increase of H 2uptake (i.e.,the slope of the lines in Figure 8)increases as the interlayer distance increases at the same conditions of temper-ature and pressure,yielding significantly enhanced uptake at higher pressures for higher ILD separations.This could be attributed to the distribution of hydrogen molecules between adsorbent molecules,as seen from radial distribution functions (RDFs)between C and H 2,shown in Figure 9.At an ILD of 6.5Å,a relatively sharp peak is observed at a distance between 3.5and 4.5Å,with a shoulder appearing at about 5Å.This fairly sharp peak indicates that the majority of the H 2molecules located between adsorbent molecules are dis-tributed in a relatively thin layer,possibly interacting with the Li atom on top,whereas the shoulder may correspond to the molecules in a second layer located in the intermolecular space.As the ILD increases to 8Å,a broader peak (Figure 9)covers a distance between 4.0and 7Å,which reveals the larger space accessible to hydrogen molecules and the thickening of the adsorption layer.These features are clearly illustrated in Figure 10.At an ILD of 10Å,two broad (overlapping)peaks are evident in Figure 9,centered in ∼4and ∼7Årespectively,corresponding to the formation of two adsorption layers of hydrogen molecules between adsorbent molecules.The formation of two adsorption layers might explain the large increase in H 2uptake when the ILD increases from 8to 10Å.Similar H 2distribution has been found in single-wall and double-wall carbon nanotubes,and especially in GNFs as the VDW gaps increase in these systems.44According toourFigure 8.Calculated hydrogen uptake capacity of Li 6-C 20H 10molecules assembled in stacks.(a)ILD )6.5Å,273K;(b)ILD )6.5Å,300K;(c)ILD )8Å,273K;(d)ILD )8Å,300K;(e)ILD )10Å,273K;(f)ILD )10Å,300K.Figure 9.Radial distribution function of pairs C -H 2for the adsorption of H 2in stacks of the Li 6-C 20H 10complex at 273K:(a)ILD )6.5Å,P )119bar,and H 2uptake of 3.63wt %;(b)ILD )8Å,P )118bar,and H 2uptake of 3.95wt %;(c)ILD )10Å,P )114bar,and H 2uptake of 4.61wt%.Figure 10.Snapshots of Li 6-C 20H 10systems of adsorbent layers with hydrogen adsorbed at ILD )8Å,300K,and 124bar.22538J.Phys.Chem.B,Vol.110,No.45,2006Zhang et al.。

美国Atmos Energy公司管理员James M. Doyle写的关于管道设备检查的文件说明书

PERIODIC INSPECTION OF REGFULATORS AND RELIEF VALVESJames M. DoyleOperations SupervisorAtmos Energy Co.106 N. BradshawDenton, Texas USAIntroductionInspections and tests on regulators and relief valves is a Department of Transportation Compliance rule. The sections within the DOT manual stating the rule include 192.351 through 192.359, 192.751, 192.479, 192.481, 192.739, and 192.741. Keep in mind; these rules are the minimum required tests. Your Company or Regulatory Agency may be more stringent and require more or detailed testing. You must also keep in mind that the Manufacturer of your equipment will also provide a guideline pertaining to maintenance. These tests are not only required for safe, reliable service to your Customers, but also could be used in any legal proceeding for documentation and purpose.There are many important tasks and precautionary measures to perform and inform before you actually start the actual testing. Listing these items and performing a checklist could provide to be a reminder. Some station designs and equipment installations may require more than one person to perform a safe, reliable test. Plan the procedure within your work group, be sure all safety equipment and notifications are in place, perform the task and document the results according to your Company procedures.We must also be aware of the Operator Qualifications rule. The Technician must be completely OQ qualified and have the proof of all the required OQ tests readily accessible.Most importantly, these required DOT and Regulatory Agency tests are done for the safety of the system, customers and you.CommunicationsBefore the testing begins, there may be many other departments within your company and customers that requires to be notified of the task. SCADA systems may be attached to the piping. These systems which are called telemeters or RTU’s are used to control pressures within the system.Customers within a local, general area may need to be notified of blowing gas noise or smell. This notification is easy and could eliminate a possible emergency situation. Local Authorities may require a notification as well.Customer call center notification is also a good policy. In case of a passerby or some one not within your communications loop, does notify the Call Center of a possible indecent, the Center will be aware of the task and can explain the reasoning to the person for their concern and call.Prepare and observeBe aware of your surroundings. The station and components must be readily accessible and protected from stress, rain and debris. The station must also be protected from equipment submerge possibilities if within a possible flooding area. Traffic control or concerns should be implemented if required. This could revert back to the communication effort to Authorities. Observe the stations surroundings such as a fence or vehicular crash barriers. Be aware of above head power lines, or any source of ignition.Review the station design and recognize the flow pattern of the station. Observe valve locations and their correct operation. By-passing the station may be required. Check all valves before the testing for proper operation and required locking devices. Be attentive to pressure setting stamps or tags. Check pipe fittings such as nipples. These fittings must meet wall thickness requirements in which the system Maximum Allowable Operating Pressure (MAOP) dictates. Check for atmospheric corrosion issues. All above ground piping must be properly coated as to eliminate atmospheric corrosion. Observe station Cathodic protection insulators (if applicable). Be sure tubing and or nipples are not connected to the piping around an insulator. This could result in a transient or stray current coming into contact with your measurement electronic devices.Use the proper tools and equipment, along with your PPE. Do not take a short cut! Injuries are usually the out come of a short cut.In summation, prepare yourself and others before the task begins. These items listed aboveif found abnormal may affect the proper operation of the station and therefore nullify your efforts during the tests.Test minimum requirementsWhen you are ready to begin the testing of the regulator(s), be sure you have made your communication efforts, surveyed your surroundings and made all safety precautions, recognize the station design and flow pattern, and installed all appropriate gauges along the station piping for monitoring pressures as you test.According to the DOT Rule, 192.739 all pressure reducing devices such as single reducing regulator(s) and a worker/monitor set up must be test once each calendar year, not to exceed 15 months. The Technician must monitor inlet and outlet pressures as the testing is performed (that is the minimum requirement). The Technician must also be positively knowledgeable of the systems normal operational pressure and MAOP. A Lock-up test may be performed, as well as proper operation of the equipment. The regulator vents must be protected from debris and rain, and if inside a structure, the vent must be piped to the outside atmosphere. A worker/monitor set-up system must be recognized as to which regulator is performing what duty in the system, and the correct pressure settings known. A stamp or tag may provide to be very useful when attached to the equipment.Manufacturer requirements for maintenance should be considered during every inspection or test, along with your Regulatory Agency requirements.Relief valve or pressure limitingRelief Valve testing is also required just as pressure reducing devices are under the sub part 192 sections of the DOT rule. These devices must be test once each calendar year, not to exceed 15 months. The relief valves proper operational test is imperative to safety for the system and protection to our customers should a failure occur. Relief valves are set to a pressure that will allow the activation of the device so that the systems MAOP are not compromised. That pressure setting must be stamped or tagged on the device and accessible at all times. A valve located under the relieving device must also be locked into the open position during normal conditions. Rain caps or other barriers must be placed on the device as to not allow debris or rain to penetrate the internal components of the device.The capacity of the relief valve must be reviewed annually. If any station parameter is changed, such as spring ranges, regulator core size, component changes, or anything that may affect the capacity of the station output, a review of that relief valve capacity must be checked and calculated by qualified personnel. This may require a new calculation sheet, and or re-sizing of the component.NotablesAnother part of the DOT rule 192.741 that applies to regulator stations concerns recording pressures that are output into the system.If a system has more that one regulator station providing service, the Operator must have pressure recording device(s) placed within the system, or a telemeter/RTU monitoring the output of the station. These recording devices will provide feedback on indications of high or low abnormal system pressure. When an indication such as this occurs, the regulator(s) must be inspected for proper operation and any unsatisfactory condition found repaired.If the system has only one regulator station providing service, the Operator has the discretion of installing such pressure recording or telemeter/RTU equipment. The Operator should take into account several items before making that decision. These items may include Customer count, location, condition or any safety related issue.DocumentationAll DOT test required documentation must be kept for the life of the facility. These records should be accessible by Regulatory Authorities and other Company Personnel at all times. The Technician must be accurate and complete with all testing information. These documents not only provide the information required to satisfy the DOT Rule, but can also be used in a legal proceeding.ConclusionThe testing procedures for satisfying the DOT section 192 sub-parts for regulators and relief valves is all about safety. That safety is specifically stated to our systems that provide ourCustomers the fuel for their comforts. As stated, the DOT sub-part 192 sections applicable to this compliance is the minimum requirement necessary. There are many other items of importance that we as Operators must observe during these tests. Ironically, all these items also immediately bring safety and reliable service to the fore front.Our OQ procedures must also be followed as to the competency of the Technician and the tasks being performed.Refer to your Vendors or manufacturers of the specific equipment that your Company chooses to purchase and use. They are a great source for specific training needs.。

林菲尔·拜肯斯朗电动液

SAM400 & 650 PERKINS DIESEL ENGINE DRIVENIM568 April, 1997Mar ‘95Mar ‘95Mar.‘93for selecting a QUALITY product by Lincoln Electric.We want you to take pride in operating this Lincoln Electric Company product •••as much pride as we have in bringing this product to you!Read this Operators Manual completely before attempting to use this equipment.Save this manual and keep it handy for quick reference.Pay particular attention to the safety instructions we have provided for your protection.The level of seriousness to be applied to each is explained below:vv(1)Consult applicable federal, state and local laws regardingspecific requirements for use on public highways.SPEED CONTROL LEVERManually allows the engine to run at its high idle speed controlled by the governor or at the factory set low idle speed.When welding or using auxiliary power the speed control lever must be in the “RUN”position.T o reduce the engine to low idle speed when not welding or not using auxiliary power place the speed control lever in the “IDLE”position notch.ENGINE TEMPERATURE GAUGEDisplays the coolant temperature in the engine block. OIL PRESSURE GAUGEDisplays the oil pressure to the engine.When the engine starts running, watch for the oil pressure to build up.If no pressure shows within 30 seconds, stop the engine and consult the engine instruction manual. BATTERY CHARGING AMMETERDisplays the current going from the charging alternator into the batteries.It is normal for charging current to be high (above 15 amps) after starting or when the batter-ies are ‘low’on charge.ENGINE HOUR METER(Factory Installed Optional Feature)The optional engine hour meter records the total run-ning time on the engine in hours.It can be used to keep a record of maintenance on the engine and or welder. ENGINE PROTECTION SYSTEMThe engine protection system shuts down the engine under high coolant temperature or low oil pressure conditions by allowing the fuel solenoid valve to close.place.3.Remove the two screws on the top end of the wirefeeder nameplate.4.Position the “Portable Field Control”mounting slotsover these holes and replace the screws.5.Route the leads with the LN-5 or LN-6 control cableback to the power source.MOUNTING ON LN-71.Remove the top screws on the side of the LN-7 con-trol box cover.(This is the left side when facing the nameplate).2.Position the “Portable Field Control”on the side ofthe control box with the mounting slots over these holes and replace the screws.3.Route the leads with the LN-7 control cable back tothe power source.OUTPUT STUDSWith the Engine OFF connect the work cable to the “T o Work”stud.A.For Stick Electrode Welding1.Connect the electrode cable to the “Stick”studand the work cable to the “T o Work”stud.Connect the “T AP”lead in the SAM650 to theappropriate stud to adjust current and the arccharacteristics as described under “Currentand Voltage Controls.”2.Install the “Portable Field Control”.B.Automatic or Semiautomatic WeldingFor all automatic welding processes, connect the welding power cable from the wire feeder to the “Connect to Auto.Equipment”stud.Connect the “T AP”lead in the SAM650 to the appropriate stud to adjust current and the arc characteristics as described under “Current and Voltage Controls.”1.LN-7, LN-8, LN-9, NA-3, NA-5, LT-7 and LT-56 Wire Feeders.a.Make the connections exactly as speci-fied on the connection wiring diagramincluded in the wire feeder InstructionManual.b.Install the “Portable Field Control”whenusing an LN-7.CURRENT AND VOLTAGE CONTROLS Constant Voltage WeldingThe SAM-400 “Current Control”is NOT in the circuit when the ‘Electrode Polarity’switch is set for constant voltage welding.Set the open circuit voltage (OCV) needed for the par-ticular application with the “Constant Voltage Control”located to the left of the nameplate.Adjust the final welding voltage with either the wire feeder voltage con-trol or the “Portable Field Control”.Set the welding cur-rent with “Amps”or “Wire Feed Speed”control on the wire feeder.Low Range Feature (SAM400 K1279-1 only) --Extends the output voltage range of the SAM400 welder down to 12 volts for constant voltage welding. The maximum output current is not to exceed the rat-ing of the machine.The Low Range Feature provides a two-position manual switch which allows the operator to set his machine for normal welding or for low voltage welding.Factory installed only.On the SAM650 connect the “T ap”lead inside the machine to the appropriate “Innershield”stud for”Min. (Flat) Slope.”“Med.Slope”or “Max.Slope”.Low voltage (below 20 volts) low current welding often requires “Max.Slope”to adjust the weld metal droplet size for minimum spatter and to control puddle fluidity and bead shape.Innershield and other spray transfer type processes generally operate with “Med.Slope”.A Hot Start circuit on all models operates automatical-ly whenever the toggle switch is set on “Constant Voltage.”It increases the open circuit voltage by sev-eral volts until the arc is established -- then the voltage automatically drops to normal welding voltage.When the wire feeder is started before the arc is started, the voltmeter indicates a voltage several volts higher than welding voltage.T o read actual welding voltage, the arc must be established.Constant Voltage Welding With Variable Inductance Control:SAM-400 Only.Variable inductance or slope control is usually desir-able for low voltage (below 20 volts) applications and is sometimes useful in other constant voltage jobs.To introduce this control into the circuit, set the “Electrode Polarity”switch to “Variable Voltage”and the toggle switch to “Constant Voltage”.Then the “Current Control”acts as the variable inductance control. Normally this control must be kept within the 8 to 1 o’clock range.To Set The Controls -- Stick Weldinga.Make the coarse setting of welding heat with theSAM400 “Current Control”or the SAM650“T ap’”lead.b.Adjust for the desired arc characteristics with the“Variable Voltage Control”.For a soft arc desired for most welding keep this control between 7 and High.For a more digging arc, set it lower.c.If remote control is NOT desired leave the“Portable Field Control”on “High”.For remote con-trol, leave the “Variable Voltage Control”near “High”and make the adjustments described in paragraph “b”above with the “Portable Field Control”.Remember, increasing either the “Variable Voltage Control”or “Portable Field Control”setting also increases the current.To Set The Controls -- Submerged Arca.The open circuit voltage (OCV) is generally notcritical in submerged arc welding.Therefore, the “Variable Voltage Control”can usually be left between 7 and “High”-- no future adjustments are needed.b.Set SAM400 “Current Control”so the calibrationon the higher scale is a little above the current desired.Set the SAM650 “T ap”lead to the stud with the lowest current range that still provides the desired current.c.Make the final current adjustment with either thewire feeder current control or the “Portable Field Control”.Set the arc voltage with the wire feeder control.Consult the following illustrations for examples of how to set the machine.STARTING WELDERS WITH DEAD BATTERIES Array DO NOT attempt to start a SAM engine driven welder by driving the welding generator as a starter motor using the output of another welder.In addition to the possibility of damaging the machines, starting a SAM engine welder without using its starting circuit elimi-nates the operation of the flashing circuit.This can cause the generator to fail to produce any output. AUXILIARY POWERAn alternator generates 2 KVA of 120/240 volt 60 Hertz AC power.It is available either from #31 and #32 on the terminal strip or from the receptacles on the Control Panel.Be careful not to overload this circuit. The auxiliary power receptacle should only be used with three wire grounded type plugs or approved dou-ble insulated tools with two wire plugs.The alternator is protected by thermostats and fuses. DUTY CYCLEDuty cycle is based on a ten minute period and opera-tion in an ambient temperature of 104°F(40°C).The SAM400 is NEMA rated at 60% duty cycle.The SAM650 is NEMA rated at 80% duty cycle.Duty cycle is based on a ten minute period.Therefore, a 60% duty cycle welder can be operated at nameplate rated out-put for 6 minutes (8 minutes for 80% duty cycle) out of every 10 minute period without overheating.The auxiliary power can be used continuously (100% duty cycle) within its rated current capacities.STARTING INSTRUCTIONSBe sure all Pre-Operation Maintenance has been per-formed.(See Installation Section of this manual.)T o start the engine, set the speed control lever in the “RUN”position.Place ignition toggle switch in the “ON”position.Push in the engine protection system reset button (if so equipped).Engage the starter button. When the engine starts running, observe the oil pres-sure.If no pressure shows within 30 seconds, stop the engine and consult the engine operating manual.T o stop the engine, place the ignition toggle switch in the “OFF”position.When an engine is started for the first time, some of the oil will be needed to fill the passages of the lubricatingsystem.Therefore, on initial starting, run the engine forK799 Hi-Freq™-Provides high frequency plus a gas valve for TIG welding.A water valve is available as an option.Requires 115 volt AC input.Cannot be used with optional meters connected, or in constant voltage mode.(Limited to 250A - 60% Duty Cycle).K802-D Power Plug Kit -For SAM welders with stan-dard 2KVA of AC auxiliary power.Kit includes male plugs for each auxiliary receptacle.K805-1 Ether Start Kit -Injects ether for starting aid. Recommended only when engines are frequently started at temperatures under 10°F (-12°C).Ether cylinder is not included.K767-1 Undercarriage -A 4-wheel steerable under-carriage for in-plant and yard towing1with E78-14 load range (B) tubeless tires.Mounts directly to welder base.1For highway use, consult applicable federal, state and local laws regarding possible requirements for brakes, lights, fenders, etc.Linc-Thaw™- Includes meter and fuse to protect the welder when thawing frozen water pipes.(L2964-[ ] Specify SAM400 or SAM650)K704(SAM400 only) Standard Accessory Kit -Includes electrode and work cables, headshield, work clamp and electrode holder.K865(SAM400 only) Engine Hour Meter Kit -(Standard on K1279-1).Keeps track of how long engine has been eful for following recom-mended maintenance schedules on machine.SAM400 only:Inspect the oil bath air filter daily - more often in dusty conditions.When necessary clean and fill the oil bath. The filter should never be removed while the engine is running.PERIODIC MAINTENANCE1.Blow out the welder and controls with an air hose atleast once every two months.In particularly dirty locations, this cleaning may be necessary once a e low pressure air to avoid driving dirt into the insulation.2.The SAM400 current control reactor brushes areself-lubricating and should not be greased.Keep the contacts clean.This control should be moved from maximum to minimum daily to prevent the controls from sticking.3.See the engine Instruction Manual for periodicengine maintenance information.Change the crankcase oil at regular intervals using the proper grade of oil as recommended in the engine operat-ing manual.Change the oil filter in accordance with the instructions in the engine operating manual.When the filter is changed add one quart of oil to the crankcase to replace the oil held in the filter dur-ing operation.4.Belts tend to loosen after the first 30 or 40 hours ofoperation.Check the cooling fan belt and tighten if necessary.DO NOT OVER TIGHTEN.BEARING MAINTENANCEThis welder is equipped with a double-shielded ball bearing having sufficient grease to last indefinitely under normal service.Where the welder is used con-stantly or in excessively dirty locations, it may be nec-essary to add one-half ounce of grease per year.A pad of grease one inch wide, one inch long and one inch high weighs approximately one-half ounce.Over greasing is far worse than insufficient greasing. When greasing the bearings, keep all dirt out of the area.Wipe the fittings completely clean and use clean equipment.More bearing failures are caused by dirt introduced during greasing than from insufficient grease.Arcing or excessive exciter brush wear indicates a pos-sible misaligned shaft.Have an authorized Field Service Shop check and realign the shaft. COOLING SYSTEMThe SAM welders are equipped with a pressure radia-tor.Keep the radiator cap tight to prevent loss of coolant.Clean and flush the cooling system periodi-cally to prevent clogging the passage and overheating the engine.When antifreeze is needed, always use the permanent type.CONTACTOR MAINTENANCEWhere the output contactor is operated frequently when tacking or making short welds, turn the engine off and inspect the contactor every three months:1.be sure the mating surfaces of silver contacts arenot worn and all make contact at approximately the same time.2.Make sure the springs and holders are not brokenor out of adjustment.Approximate spring com-pression after making contact is 1/8”.Less than 1/16”compression indicates worn contacts that should be replaced.3.Make sure the moving contact or other movingparts are not binding.4.Check interlock contacts and springs.Be suremounting screws are tight.NOTE A:If at any time either of the Control (PC) boards is replaced, follow the calibration procedure outlined later in this sec-tion under “Control P.C.Board Calibration Procedure”.The open circuit voltage will be out of range if trimmers are not properly set.If both trimmers are set at minimum, the machine might lose excitation.NOTE B:When making continuity checks, use the 1K (X1000) or next higher range.NOTE C:Do not replace PC boards without following outlined procedure for indicated trouble -- damage may result due to other defective parts.DC on SAM400 machines or 45±1 volts forSAM650 machines.Recheck to make surereadings fall within limits.T rimmer #4 set-ting is dependent on T rimmer #3.B.Constant Voltage1.Place toggle switch in constant voltageposition.2.T urn constant voltage rheostat and portablefield control to high.3.Set T rimmer #1 so that OCV is 60±1 voltsDC on SAM400 machines or 68±1 volts forSAM650 machines.4.T urn constant voltage rheostat and portablefield control to low.5.Set T rimmer #2 so that OCV is 21±0.5 voltsDC on SAM400 machines or 22±0.5 voltsfor SAM650 machines.Recheck to makesure readings fall within limits.T rimmer #2setting is dependent on T rimmer #1.N O T E :T h i s d i a g r a m i s f o r r e f e r e n c e o n l y .I t m a y n o t b e a c c u r a t e f o r a l l m a c h i n e s c o v e r e d b y t h i s m a n u a l.T h e s p e c i f i c d i a g r a m f o r a p a r t i c u l a r c o d e i s p a s t e d i n s i d e t h e m a c h i n e o n o n e o f t h e e n c l o s u r e p a n e l s .Now Available...12th EditionThe Procedure Handbook of Arc WeldingWith over 500,000 copies of previous editions published since 1933, the Procedure Handbook is considered by many to be the “Bible”of the arc welding industry.This printing will go fast so don’t delay.Place your order now using the coupon below.The hardbound book contains over 750 pages of welding infor-mation, techniques and procedures.Much of this material has never been included in any other book.A must for all welders, supervisors, engineers and designers.Many welding instructors will want to use the book as a reference for all students by taking advantage of the low quan-tity discount prices which include shipping by 4th class parcel post.$15.00postage paid U.S.A.MainlandHow To Read Shop DrawingsThe book contains the latest information and application data on the American Welding Society Standard Welding Symbols.Detailed discussion tells how engineers and drafts-men use the “short-cut”language of symbols to pass on assembly and welding information to shop personnel.Practical exercises and examples develop the reader’s ability to visualize mechanically drawn objects as they will appear in their assembled form.187 pages with more than 100 illustrations.Size 8-1/2”x 11”Durable, cloth-covered board binding.$4.50postage paid U.S.A.MainlandNew Lessons in Arc WeldingLessons, simply written, cover manipulatory techniques;machine and electrode characteristics;related subjects, such as distortion;and supplemental information on arc welding applications, speeds and costs.Practice materials, exercises,questions and answers are suggested for each lesson.528 pages, well illustrated, 6”x 9”size, bound in simulated,gold embossed leather.$5.00postage paid U.S.A.MainlandNeed Welding Training?The Lincoln Electric Company operates the oldest and most respected Arc Welding School in the United States at its corporate headquarters in Cleveland, Ohio.Over 100,000students have graduated.Tuition is low and the training is “hands on”For details write:Lincoln Welding School 22801 St.Clair Ave.Cleveland, Ohio 44117-1199.and ask for bulletin ED-80 or call 216-383-2259 and ask for the Welding School Registrar.Lincoln Welding SchoolBASIC COURSE $700.005 weeks of fundamentalsThere is a 10%discount on all orders of $50.00 or more for shipment at one time to one location.Orders of $50 or less before discount or orders outside of North America must be prepaid with charge, check or money order in U.S. Funds Only.Prices include shipment by 4th Class Book Rate for U.S.A. Mainland Only.Please allow up to 4 weeks for delivery.UPS Shipping for North America Only.All prepaid orders that request UPS shipment please add:$5.00For order value up to $49.99$10.00For order value between $50.00 & $99.99$15.00For order value between $100.00 & $149.00For North America invoiced orders over $50.00 & credit card orders, if UPS is requested, it will be invoiced or charged to you at cost.Outside U.S.A. Mainland order must be prepaid in U.S. Funds.Please add $2.00 per book for surface mail or $15.00 per book for air parcel post shipment.METHOD OF PAYMENT:(Sorry, No C.O.D.Orders)CHECK ONE:Name:_______________________________________________Address:_______________________________________________Ohio 44117-1199216-361-5901.JapaneseChineseKoreanArabicREAD AND UNDERSTAND THE MANUFACTURER’S INSTRUCTION FOR THIS EQUIPMENT AND THE CONSUMABLES TO BE USED AND FOLLOW YOUR EMPLOYER’S SAFETY PRACTICES.SE RECOMIENDA LEER Y ENTENDER LAS INSTRUCCIONES DEL FABRICANTE PARA EL USO DE ESTE EQUIPO Y LOS CONSUMIBLES QUE VA A UTILIZAR, SIGA LAS MEDIDAS DE SEGURIDAD DE SU SUPERVISOR.LISEZ ET COMPRENEZ LES INSTRUCTIONS DU FABRICANT EN CE QUI REGARDE CET EQUIPMENT ET LES PRODUITS A ETRE EMPLOYES ET SUIVEZ LES PROCEDURES DE SECURITE DE VOTRE EMPLOYEUR.LESEN SIE UND BEFOLGEN SIE DIE BETRIEBSANLEITUNG DER ANLAGE UND DEN ELEKTRODENEINSATZ DES HER-STELLERS. DIE UNFALLVERHÜTUNGSVORSCHRIFTEN DES ARBEITGEBERS SIND EBENFALLS ZU BEACHTEN.JapaneseChineseKoreanArabicLEIA E COMPREENDA AS INSTRUÇÕES DO FABRICANTE PARA ESTE EQUIPAMENTO E AS PARTES DE USO, E SIGA AS PRÁTICAS DE SEGURANÇA DO EMPREGADOR.。

石墨烯气凝胶制备方法整理

［3］Nguyen S T，Nguyen H T，Rinaldi A，et al．Morphology control and thermal stability of binderless-graphene aerogels from graphite for energy storage applications［J］．Colloids ＆ Surfaces A Physicochemical ＆ Engineering Aspects，2012,414(46):352-358．
例如，我们可以利用石墨烯气凝胶的整体性结构，可以直接或与其他材料复合当作超级电容器或是锂离子电池电极来使用，而不需要添加导电剂和粘结剂；也能够利用其拥有的大量的微米级的孔道结构（这些分级孔结构有利于高粘度流体的运输，对于油类物质和有机污染物表现出极高的吸附能力），对水中污染物进行吸附；或是利用良好的疏水性、较大的比表面积和特殊的孔结构，使有毒有害气体可以很好地与活性吸附位点发生相互作用，吸附和富集在气凝胶上；还可以通过对石墨烯气凝胶进行N、S掺杂后，使气凝胶表现出更为优异的催化效果等等。
图1
水热还原法不使用粘结剂和化学添加剂，避免了非碳杂质的引入，操作简便，但该法的反应环境较为苛刻，一定程度上限制了其应用。
化学还原组装与水热还原法相比，化学还原法反应装置简单、反应条件温和，更容易实现大规模生产。化学还原GO形成三维石墨烯组装体的过程中，除了GO分散液必须具有一定的浓度外，还原剂的选择也尤为重要。碘化钠、氢碘酸、硫化钠、对苯二酚、抗坏血酸、多巴胺、三聚氰胺等还原剂均被用于还原GO，制备GA。
电化学还原组装通过电化学还原可以直接在电极材料表面沉积获得三维自组装的石墨烯凝胶，具有反应速度快、简便、易控等优点。例如在GO的分散液(3.0mg/mL)中加入LiClO4(0.10mol/L)，通过GO对Li+的选择性吸附，使GO片层的带电特性改变，在电场的驱动下，带正电的GO片层在阴极附近富集，被电化学还原的GO疏水性增强、共轭结构恢复在电极表面完成自组装，形成垂直于电极表面的三维连通结构石墨烯。由于基底与GA结构的相互作用，增加了电子的传输，使得电化学还原组装制备的GA具有优异的超级电容性能。

美国推出网印油墨的低固化添加剂

国际涂料公司总裁Ｓｅｅａａｅ．３０ｔＰｎ说ｈＫｈｎ８４苯二甲酸（）固化添加剂为当前市场上日益扩Ｐ低Ｆ大的热敏感基板提供了新的印花机遇。几家大型印
刷厂的Ｂｔ实验结果非常积极，显示３０苯二ｅａ８４甲酸（）固化添加剂非常容易使用，效果令人Ｐ低Ｆ满意。３０苯二甲酸（）固化添加剂为热敏感基８４Ｐ低Ｆ板提供一个印刷解决方案，当放在传统烤箱或者烘
料用树脂新品种申请表。对认为存在
定毒性、
对人体有害的物质，填报《建议禁止用于食品包装材料的物质名单》。《通知》指出卫生部会同有关部门成立专家组，对行业、企业提交的材料进行科学评估，根据
评估结果拟定《用于食品包装材料的物质名单》可和《止用于食品包装材料的物质名单》，并分批禁向社会公布。对于《止用于食品包装材料的物质禁名单》发布后仍继续使用名单中的物质制售食品包
＿萼 ■＿；
投诉举报电话或电子邮箱发动群众举报非法生
卫生部等７联合开展食品包装材料清理工作部门
卫生部等７门日前联合下发《于开展食部关品包装材料清理工作的通知》（下简称 “ 《以通知》 ” ），要求政府各相关部门广泛发动各行业、企业，按照《品安全法》的规定，对市场上存在食

镁离子电池研究进展

2020年第23期广东化工第47卷总第433期 · 81 ·镁离子电池研究进展马超，李茂龙，丁一鸣，贺畅，曹志翔，鲍克燕(江苏理工学院化学与环境工程学院，江苏常州213001)[摘要]镁电池因具有比锂离子电池更高的安全性和更低廉的价格而受到越来越多的关注，近些年研究者们针对高性能镁电解质的开发、嵌镁正极材料设计等方面投入了大量研究，许多技术壁垒也不断被突破。

本文对镁电池的研究成果进行了调研并综述。

[关键词]镁离子电池；正极材料；电解液[中图分类号]TQ [文献标识码]A [文章编号]1007-1865(2020)23-0081-01Research Progress of Magnesium Ion BatteriesMa Chao, Li Maolong, Ding Yiming, He Chang, Cao Zhixiang, Bao Keyan(School of Chemical and Environmental Engineering, Jiangsu University of Technology, Changzhou 213001, China) Abstract: Magnesium batteries have attracted more and more attention because of their higher safety and lower price than lithium ion batteries. In recent years, researchers have invested a lot of research in the development of high-performance magnesium electrolytes, positive electrode materials, and many technical barriers have been constantly broken. In this paper, the research magnesium ion batteries are investigated and reviewed.Key words: magnesium ion batteries；positive electrode materials；the electrolyte锂离子电池具有多种优势，但是锂负极枝晶的形成会导致安全隐患，此外，地球上有限的锂资源也成为锂离子电池制造行业关注的问题。

迷你指南 Gastec燃气检测管组合套装说明书

• Provides immediate identifi-cation of unknown gases on the spot by just following the flowchart • No batteries or electrical power required • Requires fewer pump strokes and provides faster results • Gastec samplng pumps and de-tector tubes are pre-calibrated and are always ready to useFIRE AND RESCUE SERVICES Gastec Polytec Gas Detector Tubes with Gastec Sampling Pump GV-100 or GV-110,and TG-1 system provide ad-vanced quick and accurate qualitative and quantitative analysis of unknown gases and vapours.MARINE AND SHIPPING TECHNOL-OGIESNo batteries or special training re-quired Gastec Gas Detector Tubes and Sampling Pumps provide highly accu-rate measurements on site for applica-tions such as fumigation or detection of chemicals on tankers. Gastec tubes are available in most ports through world wide retailing channels.OIL REFINING CHEMICAL PLANTS A non sparking design makes the Gas-tec Sampling Pumps the ideal measure-ment tool in environments classed for intrinsic safety.MINING AND UNDERGROUND With less pump strokes Gastec Detec-tor Tubes provide immediate measure-ment results with clear colour demarca-tions for applications such as emission test for vehicle ERNMENTSWeighting a mere 245g, Gastec Sam-pling Pumps are light enough to be easily carried to any site and get mea-surement results in a few BORATORIESGastec enables quick and accurate analysis with access to timely techni-cal support.SCHOOLSGastec Gas Detector Tube System is also applicable to all grade levels and can be used to demonstrate the prin-cipals of photosynthesis, respiration, combustion, or for field projects such as global warming.Gastec Detector Tubes indicate concentrations directly by way of a calibrated scale printed on the tubes. Gastec, endeavours to achieve highest quality de-tector tubes for analysing airborne gases/vapours, as well as pollutants in soil and water through our advanced state-of-the-art research and development. Through our efforts we have acquired a solid reputation among our customers in virtually all sectors of industry, commerce and society. Tubes are now available for more than 500 different applications.KEY FEATURESThe pump piston has been designed with a smaller diameter so that the handle can be pulled out with even less effort. This permits anyone to operate the pump easily. Also Gastec pump Model GV-110 and GV-100 meet the leakage test of EN1231, Workplace atmospheres-Short term detector tube measurement sys-tems-Requirements and test methods, 4.2 Detector tube pump, 4.2.2 Leakage “The detector tube pump with the closed detector tube connection shall be tight, so that during the first minute of a pump stroke the leakage rate does not exceed 3mLJmin.” The Gastec pump shaft shows you the leakage rates with red line.The pump body is covered with a soft elastomer, with the middle portion nar-rower than the ends to ensure a firm grip on the pump cylinder. The other outer surfaces of the pump a re made of non sparking material Is of ABS resin except for the opening of the tube tip cutter that is made of chromed stainless steel.The full-stroke (100ml) and the half-stroke (SOmL) positions are marked exactly by the red line on the pump shaft, and the handle is precisely locked at those positions. The attached flow finish indicator tells you automatically when thestroke is complete. When the white disk pops out, the sample is complete.The automatic stroke counter built in the model GV-110 gas sampling pump cantrack up to ten pump strokes automatically so there is no chance of miscounting.Calibration scale (in ppm, mg/m³, mg/L or % depending on the substance to be measured andits concentration). Printed in an ink that permits high legibility against the colour change layer. The scale is determined for each production lot that has passed Gastec’s exacting qualification tests.Standard number of pump strokes (n). The number of pump strokes required to collect the standard volume of sample air for this tube.Quality control number (QC No.). Gastec’s quality assurance number is printed on every Gastec detector tube. Detector tubes of the same production lot have the same QC No. When a QC No. is registered, sample tubes with that QC No. will be kept and monitored periodically to verify the quality.Reliable detecting reagents that comply with the Gastec’s stringent quality standards (regulating the length of colour change layer, the clearness of demarcation, and the tone and brightness of colour change).High quality glass tubeChemical formula of the substance to be measured.An abbreviation is used for a long formula.Detector tube number. The numeral represents thekind of substance the tube can measure, and theletter specifies the level of concentrations the tubecan determine. For Example, H, M and L respectivelyindicate high, middle, and low level concentrations.Distinct layer of colour changeMEASUREMENT PROCEDURE WITH GASTEC DETECTOR TUBE SYSTEMThe primary step is providing countermeasures against hazardous gas generation for occupational hygiene control and pollution control is to acquire accurate data regarding gas types and their concentration levels. Our T oxic Gas Detection Kit includes 12 detection tubes.1. Confirm the direction of air flow at the measurement site by using the No. 500 Smoke T ester Set.2. Connect the No.350A Extension Hose to the Model GV-100 Gas Sampling Pump, when necessary.3. Break off both ends of a Polytec Tube No.107 and connect the tube to the Pump, or to the end of the Extension Hosewhen it is used.4. Pull out the handle of the Pump, wait for the predetermined sampling time and examine the tube for colour change.5. Proceed with the measurements by using all 12 kinds of detector tubes as shown in the following toxic gas determinationflowchart.6. Finally, determine the pollutants from the measurement results.QUALITATIVE ANAL YSIS SYSTEMFOR UNKNOWN GASESThe Gastec Polytec System consistsof the Model GV-100 or GV-110 GasSampling Pump and the Polytec Tubes.The Polytec Tubes are unique detectortubes, each having 1 to 7 reaction lay-ers to determine multiple unknown sub-stances in the sample simultaneously.When you pull the handle of the Pumpand wait for a predetermined samplingtime, the colour(s) of the Polytec tube’slayer(s) change uniquely according tothe contents of the sample. Four typesof Polytec Tubes are available: PolytecI (No. 107), Polytec II (No. 25), PolytecIll (No. 26), and Polytec IV (No. 27). De-tailed descriptions are given in the in-struction sheets included with individualPolytec Tubes.Substance Concentration Changes colour from white to Carbon disulphide ≥ 1 ppmGreenHydrogen sulphide ≥ 1 ppmCarbon monoxide≥ 10 ppm Green or BrownAcetone ≥ 1000 ppmAcetylene ≥ 10 ppmBrown or Green Ethylene ≥ 70 ppmBenzene≥ 20 ppmBrownPropane, Propylene≥ 100 ppmStyrene ≥ 10 ppm Y ellow or Brown Trichloroethylene≥ 15 ppm Pale BrownGasoline ≥ 100 ppm BrownT oluene, Xylene≥ 10 ppm PurpleACCESSORIESEXTENSION HOSE NO. 350A/350A-10A rubber extension hose for remote measurement down manholes and into tanks which might present a hazard to anyone entering them. Available in 2 sizes: No.350A for Sm and No.350A-10 for 10m. Use extension guard (No. 3 5 7) as a replacement extension hose end, or when measuring with twin tubes.ONE HAND OPERATION ADAPTER GV-700Gastec Model GV-700 Adapter can maintain a vacuum of SO ml or 100ml In the pump body. This allows the user to attach the appropriate tube to the pump, and then In situations where It Is necessary, to ta Ice the sample using one hand. In the body of the Adapler there Is a small rod which can be moved In or out quite easily with oneflnger.PYROTEC PYROL YZER NO.840 (FOR TUBE 51H, 51,51L, 53)Gastec developed the Pyrotec Pyrolyzer which converts the flu oroch lo roca rbon gas family and halogenated hydrocarbons by thermally cracking them into a gas which can be easily measu red. Now, fl uoroc h lorocarbo n gases a re easy and precisely mea-sured by simply using a Pyrotec Tube with the Pyrotec Pyroly:zer.HOT PROBE NO.340HOT PROBE HOLDER NO.345AA cooling f in accessory for measuring high temperature gases (up to approx. 600 /1 112 ) such as furnace and automotive exhaust gases. The sample is cooled to ambient temperature for accurate concent ration measurements. Use hot probe holder (No. 345A) to attach the hot probe for better stability.GASTEC HANDBOOKThe Handbook is designed to be easier to use and more infor-mative for a wide variety of people who are responsible for the management of not only work places and offices, but also of public facilities and premises (including air, water, and the soil). The in-formation is presented in a format that we feel useful to both the beginner and the experienced health and safety profession a I.TUBE TIP HOLDER NO.721The Tip Holder functions as a tip breaker for t he detector tubes and also stores the broken tips, thereby preventing glass frag-ments from scattering. It can hold about 260 broken tips.SMOKE TESTER SET NO.SOOThis set allows t he operator to test air f lows In workplaces ac-curately and easily. Just break ‘ off both ends of a No.501 Smoke Generation, Tube (6 tubes/box) and connect the tube to the rub-ber bulb. Squeezing the bulb provides atmospheric moisture that reacts with the reagent In the tube, generating a white smoke . A single No.501 tube can be used repeatedly for 50 to 100 tests by sealing the tube ends with the rubber caps after each test.EXTENSION SAMPLING POLE NO.350BP-2A telescopic glass fibre probe suitable for horizontal or upward extension to sample gases and vapours in narrow spaces. The length of the pole can be adjusted from 62.5cm to 2.8m (2.1 to 9.2ft). It weighs only 590g (1.3 lb).1. No.350BP-2 Extension Sampling Pole2. Gastec standard De1ector TU be System attached to theNo.350BP..2 Extension Sampling Pole.。

扶手椅型石墨烯纳米带吸附钛原子链的电子结构和磁性

扶手椅型石墨烯纳米带吸附钛原子链的电子结构和磁性孙凯刚;解忧;周安宁;陈立勇;庞绍芳;张建民【摘要】采用基于密度泛函理论的第一性原理方法,研究了扶手椅型石墨烯纳米带(10G、11G、12G和13G)吸附zigzag型Ti原子链的几何结构、电子性质和磁性.结果表明,zigzag型Ti原子链可以稳定吸附在石墨烯纳米带表面.Ti原子链吸附在纳米带的边缘洞位(10G-1、11G-1、12G-1和13G-1)时较为稳定,且稳定程度随着纳米带宽度的增加而增加.Ti原子链吸附在不同宽度石墨烯纳米带的不同位置,呈现不同的电子结构特性.其中,10G-1、10G-2和11G-2的吸附体系表现出半金属特性,其余吸附体系都为金属性质.同时,石墨烯纳米带吸附Ti原子链的体系具有磁性,其磁性主要来源于Ti原子.当Ti原子链吸附在纳米带边缘洞位时,zigzag原子链上A类Ti原子的磁矩总是小于B类Ti原子的磁矩;随着Ti原子链移向纳米带中心,两类Ti原子的磁矩趋于相等.研究结果揭示,通过吸附zigzag型Ti原子链,可以有效调控石墨烯纳米带的电子结构与磁性质.【期刊名称】《陕西师范大学学报（自然科学版）》【年(卷),期】2016(044)002【总页数】6页(P27-32)【关键词】石墨烯纳米带;原子链;电子结构;磁性;密度泛函理论【作者】孙凯刚;解忧;周安宁;陈立勇;庞绍芳;张建民【作者单位】西安科技大学理学院,陕西西安710054;西安科技大学理学院,陕西西安710054;西安科技大学化学与化工学院,陕西西安710054;西安科技大学理学院,陕西西安710054;西安科技大学理学院,陕西西安710054;陕西师范大学物理学与信息技术学院,陕西西安710119【正文语种】中文【中图分类】O469PACS: 73.22.Pr, 75.75.-c, 61.48.Gh, 31.15.E-石墨烯(graphene)[1]自从在实验上被成功制备以来，就以其新奇而丰富的物理化学性质引起了科技工作者的广泛关注。

BONDSTRAND

Bondstrand Glassfiber Reinforced Epoxy Piping SystemsHistorically, offshore production platform, drilling rig and FPSO owners and operators have had to face the grim reality of continuously replacing most metal piping because of severe corrosion. This has resulted in piping systems costing two or three times the original investment since steel and metal pipe systems are very costly to maintain. Bondstrand GRE pipe systems are the cost-effective, maintenance-free and lightweight solution that providescorrosion-free and erosion-free operation during the service life of the vessel.Durable and corrosion resistantBondstrand GRE is highly resistant to corrosion caused by (salt) water, chemicals, residues and bacteria.Similarly, it resists corrosion even in aggressive environments. Cathodic protection is not required.Lightweight – easy to installBondstrand GRE pipes weigh only a quarter to an eighth of steel pipes and are easy to install without the need of heavy nstallation equipment, welding or protective coating. For installation of GRE piping systems no ‘hot’ work is required.Low installation and operating costsInstallation costs of Bondstrand GRE pipe systems are less than that of carbon steel; total installed costs are comparable. Operating costs areThe many advantages of Bondstrand GRE pipe systemsreduced due to less energy needed to pump fluid through the smooth internal bore.Wide range of pipe systemsFiber Glass Systems offers a complete range of pipe systems in a variety of diameters and pressure classes for many different applications. Pipe systems are available in diameters up to 1000 mm (40 inch), and standard lengths up to 12 m (40 feet).No contaminationBondstrand GRE does not rust or scale. This prevents plugging of nozzles, valves and other components.WIDE RANGE OF APPLICATIONSOur corrosion-resistant piping systems can be used in a wide range of applications.Typical application areas are:COST COMPARISONCONVENTIONAL STEEL SYSTEMSTOTAL INSTALLED COST EQUALS T RADITIONAL STEEL PIPING A comparison of costs clearly shows the typical savings during the service life of the piping system.WIDE RANGE OF SOLUTIONSAs a leading producer Fiber Glass Systems offers the world’s mostcomprehensive range of glassfiber reinforced epoxy and phenolic pipe systems. Whether you need corrosion protection, fire protection, or a conductive system, Fiber Glass Systems offers t he right choice. Bondstrand GRE pipe series • Ballast water • Caissons • Cooling water • Disposal • Deluge (dry)• Drains • Drilling mud • Fresh water• Potable water • Produced water • Fire mains• Saltwater / seawater • Sanitary / sewage • Column piping • Vent linesSizes25-1000 mm (1–40 inch)Pressure classes up to 25 bar (365 psi)Internal liners available if neededConductive systems available if needed Joining systemsQuick-Lock™ and Taper/Taperadhesive bonded jointsSPECIFICATIONSISOThe objective of ISO 14692 is to provide the oil & gas industry and the supporting engineering and manufacturing industry with mutually agreed upon specifications and recommended practices for the design, purchase, manufacturing, qualification testing, handling, storage, installation, commissioning and operation of GRP (Glassfiber Reinforced Plastic - a generic terms including epoxy and other resins) piping systems.ISO 14692, part 2, 3 and 4 follow the individual phases in the life cycle of a GRP piping system, i.e. from design through manufacture tooperation. Each part is therefore aimed at the relevant parties involved in that particular phase.ISO 14692 is primarily intended for offshore applications on both fixed and floating topsides facilities, but it may also be used as guidancefor the specification, manufacture, testing and installation of GRE piping systems in other similar applications found onshore, e.g. produced water and firewater systems.IMOIn 1993, the International Maritime Organization (IMO) issued Resolution A.753(18) covering acceptance criteria for plastic materials in piping systems, appropriate design and installation requirements and fire test performance criteria for assuring ship safety. Major certifying bodies (such as Lloyd’s Register, Bureau Veritas, Det Norske Veritas, American Bureau of Shipping and United States Coast Guard) have adopted and implemented these Guidelines in their respective Rules and Regulations for the Classification of Ships and Floating Offshore facilities.All Bondstrand pipe series that are used in the marine/offshore industry are Type Approved by these major certifying bodies.Bondstrand Conductive Piping SystemsBondstrand conductive piping systems have been developed toprevent accumulation of potentially dangerous levels of static electrical charges.Pipe and flanges contain high strength conductive filaments; the fittings include a conductive liner. Combined with a conductive adhesive this provides an integral electrically continuous system.Grounding saddles can be bonded on the pipe. Integral grounding cables are then bolted to the steel structure to drain accumulatedcharges.Bondstrand conductive piping systems** Conductive version of Bondstrand 2000M (1) 2425 Bondstrand SeriesNote: All systems are available with a fire-protection layer.PRODUCT OVERVIEW(External pressure rating according to IMO Regulations)ENGINEERING CAPABILITIESWith manufacturing locations all over the world, Fiber Glass Systems has experienced teams of engineers supporting the customer with support design, engineering analysis, spool and isometric drawings and installation procedures.Fiber Glass Systems Engineering Service can include:• General engineering calculations such as support span, thrustloads, joint strength, collapse pressure and internal pressureratings, etc.• Design drawings, stress and surge analyses• Pipe Spool drawings from piping isometrics• Pipe support detailing• Material take offs (MTO)• Special product design for custom made parts• Expertise on international specification work towards approvalauthorities• Field service• Training to certify installersPREFABRICATIONBondstrand GRE systems are assembled using standard manufactured components. Spools can be pre-fabricated at the yard, or can be supplied from Fiber Glass Systems spooling operation or one of the network partners. The need for adhesive bonded joining on board can be limited.If pipe spacing is a constraint, Fiber Glass Systems can offer custom made spools to meet specific dimensions. Fiber Glass Systemsteam of piping engineers and fabricators can assist to ensure that custom-made spools are designed and fabricated to meet the project requirements.Pre-fabricated spools will reduce the number of field joints and provide greater reliability because of the high quality joints and testing at the Fiber Glass Systems factory.Installers, trained and certified by Fiber Glass Systems – according to IMO standards – can handle the complete installation.Fiber Glass Systems’ scope of supply may vary from material supply tocomplete ’turn-key’ projects.Prefabrication of custom made fiberglass spoolsCertified installation of Bondstrand piping systemTESTINGFIRE ENDURANCEEpoxy pipeUnder IMO Rules, Bondstrand epoxy products can be used for systems (normally water filled) without additional passive fire protection. Fire exposure will cause the outer surface of the pipe to char, but the functionality of the piping remains.Additional fire protectionDepending on the level of fire endurance required, epoxy pipe with enhanced fire resistance properties can be supplied meeting any of the following fire endurance requirements:- IMO L1- IMO L2- IMO FTP 2010- United States Coast Guard (USCG) W/D - USCG PFM 1-98- Jet Fire 30 OTI 95/634- Jet Fire 60 OTI 95/634Bondstrand fittings are tested to 1.5 times their pressure rating before they leave the factory or are used in spools. Small diameter fittings, to 150 mm (6 inch) are air tested, when possible.All others and the large diameter fittings are hydrotested. Fiber Glass Systems is the only manufacturer to conduct unrestrained hydro-test of fittings above 500 mm (20 inch) in diameter using self-energizing test plugs. Unrestrained testing is a more representative test as it simulates the actual conditions to which the pipe system is subjected in most Offshore installations.Fiber Glass Systems has extensive testing capabilities to meet special requirements. Comprehensive qualification testing is done onrepresentative sizes before manufacturing. Qualification test includes long-term hydrostatic test in accordance with ASTM D 2992, medium term survival test (1000 hour survival test) and short time burst test in accordance with ASTM D-1599. Mechanical and physical property testsof Bondstrand pipe can also be conducted.Hydrotesting of Bondstrand prefabricated pipe spool prior to shippingFire endurance testing of Bondstrand fiberglass pipe and fittingJOINING SYSTEMSQuick™ Lock- An adhesive-bonded joint with straight spigot and tapered bell. The integral pipe stop in theQuick-Lock bell provides accurate laying lengths in close tolerance piping. Available in sizes 50-400 mm (2-16 in).Taper x Taper - An adhesive-bonded joint with matching tapered male and female ends offering superiorjoint strength by controlled adhesive thickness. Available in sizes 50-1000 mm (2-40 in).Flanges - One-piece flanges and Stub-end flanges with movable rings. Available in sizes 50-1000 mm (2-40 in).Double O-Ring - A mechanical joint offering quick assembly between male and female ends. Two “O” ringsare employed to provide sealing. Available in sizes 50-900 mm (2-36 in).Fittings - Standard filament-wound Couplings; 30°, 45°, 60°, and 90° Elbows; Tees and Reducing Tees;Concentric Reducers; Flanges and Nipples. Standard Flanges are available with the following drilling: ANSIB16.5 Class 150 & 300, DIN, ISO and JIS. Other drilling patterns are available on request. Available in sizes50-1000 mm (2-40 inch)Fiber Glass Systems17115 San Pedro Avenue, Ste 200San Antonio, Texas 78232 USA Phone: 210 477 7500Fax: 210 477 7560National Oilwell Varco has produced this brochure for general information only, and it is not intended for design purposes. Although every effort has been made to maintain the accuracy and reliability of its contents, National Oilwell Varco in no way assumes responsibility for liability for any loss, damage or injury resulting from the use of information and data herein nor is any warranty expressed or implied. Always cross-reference the bulletin date with the most current version listed at the web site noted in this literature.© 2017 National Oilwell Varco All Rights Reserved MOS1100 October 2017。

氧化石墨烯纳米带能带结构和态密度的第一性原理研究

氧化石墨烯纳米带能带结构和态密度的第一性原理研究王伟华;卜祥天【摘要】The charge density, energy band structure, density of states and project density of states of graphene oxide nanoribbons were investigated using the first principle calculations based on densi-ty functional theory. The results indicate that the graphene oxide nanoribbons are an indirect band gap semiconductor with an energy gap of 0. 375 eV. The charge density is transferred among C, O and H atoms. The project density of states show that the localization and hybridization between C-2s, 2p,О-2p, H-1s electronic states are induced in the conduction band and valence band. The lo-calization is induced byО-2p electronic states at Fermi level. It plays a major role in improving the semiconductor luminescence effect of graphene oxide nanoribbons.%基于密度泛函理论,采用第一性原理方法,计算了氧化石墨烯纳米带的电荷密度、能带结构和分波态密度.结果表明,石墨烯纳米带被氧化后,转变为间接带隙半导体,带隙值为0.375 eV.电荷差分密度表明,从C原子和H原子到O原子之间有电荷的转移.分波态密度显示,在导带和价带中C-2s、2p,O-2p,H-1s电子态之间存在强烈的杂化效应.在费米能级附近,O-2p态电子局域效应的贡献明显,对于改善氧化石墨烯纳米带的半导体发光效应起到了主要作用.【期刊名称】《发光学报》【年(卷),期】2017(038)012【总页数】5页(P1617-1621)【关键词】氧化石墨烯纳米带;能带;分波态密度;第一性原理【作者】王伟华;卜祥天【作者单位】内蒙古民族大学物理与电子信息学院, 内蒙古通辽 028000;内蒙古民族大学物理与电子信息学院, 内蒙古通辽 028000【正文语种】中文【中图分类】O472.4;TB321石墨烯纳米带(GNRs)是当前研究领域中最新的研究材料之一，因为具有优良的电学和光学特性使其为制备高效的纳米电子器件提供了坚实的材料基础，引起了科学工作者的广泛关注[1]。

(美ut吸附曲线)页岩气解吸吸附规律

– Third, gas will desorb from the areas exposed to the fractures due to the high drawdown created at the fracture face.
Comparison of Two Shale Gas Plays
• The test must be conducted at reservoir temperature. • “lost gas” and “residual gas” volumes must be
evaluated to determine the total desorbed gas volume. • “Lost gas” is volume of the gas that desorbs from the
Gault and Stotts, 2007
Canister Gas Desorption
and Determination of Gas Content
• The canister desorption test is conducted by placing a freshly cut conventional core sample in a sealed container (canister) and measuring the amount of gas released as a function of time.
Shale Play #2 is a low-pressured
reservoir, with a high initial water
saturation and much better adsorption capacity (VL = 280 scf/ton, PL = 370 psia)ion Curve

考虑吸附气影响的页岩气井三项式产能计算方法

㊀㊀收稿日期:20220622;改回日期:20230216㊀㊀基金项目:国家科技重大专项彭水地区常压页岩气开发技术政策及气藏工程方案 (2016ZX05061-016);中国石化重大科技项目南川复杂构造带页岩气勘探开发关键技术 (P19017-3)㊀㊀作者简介:房大志(1984 ),男,副研究员,2006年毕业于中国石油大学(北京)环境科学专业,2009年毕业于该校石油地质专业,获硕士学位,现主要从事非常规油气勘探开发工作㊂DOI :10.3969/j.issn.1006-6535.2023.03.017考虑吸附气影响的页岩气井三项式产能计算方法房大志1,刘㊀洪2,庞㊀进2,谷红陶1,马伟骏1(1.中国石化重庆页岩气公司,重庆㊀408400;2.重庆科技学院,重庆㊀401331)摘要:针对页岩气吸附解吸对生产井产能影响规律不清晰的问题,基于致密气井的渗流特征和产能方程,从气体渗流微分方程出发,结合Langmuir 等温吸附公式,建立考虑页岩气吸附解吸的产能模型,根据页岩气井的钻完井和动态监测资料计算了页岩气井不同解吸时间下的产能和无阻流量,并根据回压试井资料,将吸附气影响转化为附加阻力系数,形成三项式产能计算方程,利用该方程研究了吸附气对页岩气产能计算的影响㊂结果表明:吸附气会导致页岩气井初期产能计算值偏高,解吸10d 后计算的无阻流量相对稳定;吸附气含量对页岩气井产能影响较大,吸附压力对产能影响较小;三项式产能计算结果与解析法模型计算结果误差小于12%,结果较为可靠㊂研究成果可为页岩气井产能评价提供参考㊂关键词:页岩气;产能;三项式;吸附气中图分类号:TE332㊀㊀文献标识码:A ㊀㊀文章编号:1006-6535(2023)03-0137-06A Trinomial Deliverability Calculation Method for Shale Gas Wells Considering the Effect of Adsorbed GasFang Dazhi 1,Liu Hong 2,Pang Jin 2,Gu Hongtao 1,Ma Weijun 1(1.Sinopec Chongqing Shale Gas Company ,Chongqing 408400,China ;2.Chongqing University of Science and Technology ,Chongqing 401331,China )Abstract :To address the problem of the unclear effect law of the shale gas adsorption -desorption on the deliver-ability of production wells ,based on the seepage characteristics and deliverability equation of tight gas wells ,a de-liverability model considering shale gas adsorption -desorption was established with reference to the gas seepage dif-ferential equation and in combination with the Langmuir isothermal adsorption equation ;the deliverability and open flow capacity of shale gas wells under different desorption time were calculated based on the drilling and completion and dynamic monitoring data of shale gas wells ,and the effect of adsorbed gas was transformed into additional re-sistance coefficients based on the information of back -pressure well testing to form a trinomial deliverability calcula-tion equation ,and this equation was used to study the effect of adsorbed gas on shale gas deliverability calculation.The results show that the adsorbed gas will cause a higher initial deliverability calculation value of shale gas wells ,and the calculated open flow capacity is relatively stable after 10d of desorption ;the adsorbed gas content has a greater influence on the deliverability of shale gas wells ,and the adsorption pressure has a smaller influence on thedeliverability ;the error between the results of the trinomial deliverability calculation and the analytical method mod-el calculation is less than 12%,and the results are more reliable.The research results can be used as a reference for the deliverability evaluation of shale gas wells.Key words :shale gas ;deliverability ;trinomial ;adsorbed gas0㊀引㊀言页岩气井产能是衡量页岩气开发效果的重要指标㊂目前,页岩气井产能计算方法主要包括经验公式法㊁解析模型法和数值模拟法㊂经验公式法是基于早期生产数据,通过产量变化规律拟合,预测㊀138㊀特种油气藏第30卷㊀不同时期的产量,常用的经验公式法有PLE㊁SEPD㊁Duong㊁LGM㊁PEPD 等[1-5]方法,但该类方法需要较长时间的产量数据,且只能预测定压生产条件下的产量,具有较大的局限性㊂解析模型法主要以页岩气地层流动和吸附解吸理论为基础,考虑页岩气在基质和裂缝系统中的流动规律,以及页岩气的吸附解吸特征,通过建立解析或者半解析模型来预测不同地质条件和生产条件下的产量[6-22]㊂该类模型通常还考虑了裂缝系统的应力敏感特征,典型的解析模型有Carlson㊁Fisher㊁Hasan㊁任俊杰㊁张烈辉㊁石军太㊁王海涛等[6-12]建立的模型,该类方法应用时需要准确的完井㊁地质和岩石物理参数,但这些参数很难全部获得,且存在预测偏差较大的问题㊂数值模拟法通过建立页岩储层地质模型,研究降压㊁解吸㊁扩散以及应力敏感现象对页岩气产能的影响,典型的数值模拟法有Williamson㊁Bustin㊁Wu㊁Freeman 等[13-16]建立的模拟方法,由于数值模拟器中的参数与实际施工或设计参数存在较大差异,产能评价仍存在较大偏差㊂上述3类产能预测方法均存在应用局限或不足,其主要原因是没有将生产数据与机理模型有机结合起来㊂因此,借鉴致密气流动理论,考虑页岩气的解吸特征,建立页岩气产能数学模型,将页岩气试气阶段的测试数据与页岩气产能数学模型结合,建立改进的页岩气井产能计算方法,为页岩气井产能评价提供科学可行的解释方法㊂1㊀页岩气井产能方程建立页岩气与致密气有相似的渗流理论基础,区别在于致密气井将吸附层的流动阻力考虑为启动压力梯度,而页岩气井中的解吸扩散气体则为页岩气井产量的补充量㊂因此,在致密气藏产能评价方法基础上,针对页岩气解吸㊁扩散特点,推导页岩气水平井产能方程,从而建立起页岩气产能评价方法㊂由于页岩气藏渗透率极低,大多采用水平井多级压裂的方式开采,故从等效压裂体积的角度出发,建立页岩气水平井产能方程㊂页岩气水平井体积压裂后形成网状裂缝,为便于计算,对裂缝系统进行了简化(图1),采用单相流模型㊂作如下假设:①气藏均质,且各向同性;②气藏边界是矩形封闭边界,水平井段位于气藏中心;③渗流过程为等温渗流;④裂缝中的流体流动符合达西渗流规律,同时不考虑裂缝与基质间的微观渗流,只研究流体流动的宏观规律;⑤单相气体渗流,忽略重力和毛管力影响;图1㊀页岩气水平井多级压裂示意图Fig.1㊀The schematic diagram of multi -stagefracturing of shale gas horizontal wells根据微观渗流速度,得到气井的产量:ν=K μ㊃d pd x(1)q x sc =ρg AνB g =ρg K (L f hN )B g μ㊃d pd x(2)从等温压缩定义推导产量公式:q x sc =2(y e -x )x e hϕC g ρg +ρg ρb V L p L(p r x -r e +p L )2τ(y e -x )x e h y e x e hϕC g ρg +ρg ρb V L p L(p r w -r e +p L )2τy e x e hq sc(3)式中:q x sc 为x 处在标准状态下的质量流量,kg /s;A为裂缝渗流截面总面积,m 2;q sc 为标准状态下产气量,m 3/s;K 为气层的有效渗透率,D;h 为气层的有效厚度,m;μ为气体黏度,mPa㊃s;Z 为气体偏差因子;ρg 为标准状况下气体密度,kg /m 3;C g 为天然气压缩系数,1/MPa;ρb 为页岩密度,kg /m 3;y e 为裂缝半长,m;x 为距井中心的距离,m;L f 为裂缝宽度,m;N 为裂缝条数,条;x e 为射孔段长度,m;τ为解吸时间,d;v 为气体渗流速度,m /s;ϕ为孔隙度;p L 为Langmuir 压力常数,MPa;V L 为Langmuir 体积常数,m 3/kg;d p /d x 为压力梯度,MPa /m;p r x -r e 为气层边界到距离x 处的平均压力,MPa;p r w -r e 为井底㊀第3期房大志等:考虑吸附气影响的页岩气井三项式产能计算方法139㊀㊀到气层边界的压力,MPa;B g 为体积系数㊂将式(2)代入式(3),引入表皮系数S ㊂同时,考虑页岩气井中的解吸扩散气体对能量的补充,引入解析扩散能量补充系数D ,得到产量表达式:q sc =246.7KL f hNρg ʏp e p wf2p μZd p +ʏp e p wfρb V L p L (p r w-r e+p L )2τ㊃1C g ϕ㊃2p μZ éëêêùûúúd p {}Tʏy e(1-xy e)d x +ʏy e 0ρb V L p L(p r x -r e +p L )2τ㊃1C g ϕ(1-x y e )éëêêùûúúd x +S +Dq sc {}(4)㊀㊀对式(4)整理㊁化简得到页岩气井产能方程:Δψ1+Δψ2=Aq sc +Bq 2sc(5)Δψ1=ʏp ep wf2p μZd p (6)Δψ2=ʏp e p wfρb V L p L(p r x -r e +p L )2τ㊃1C g ϕ㊃2pμZd p (7)ω1=4.05ˑ10-3T KL f hNρgʏy e 0(1-xy e 2)d x +ʏy eρb V L p L (p r x -r e +p L )2τ㊃1C gϕ(1-x y e 2)éëêêùûúúd x +S {}(8)ω2=4.05ˑ10-3TKL f hNρgD(9)式中:p wf 为井底流压,MPa;Δψ1为地层拟压力,MPa;Δψ2为井底拟压力,MPa;ω1为与渗流有关的阻力系数;ω2为与解吸扩散有关的阻力系数;D 为解吸扩散能量补充系数;S 为表皮系数;T 为井底温度,K ;p e 为气层边界压力,MPa㊂式(6)㊁(7)代入式(5)并整理得:(1+β)μZ ʏp e p wf2p d p =ω1q sc +ω2q 2sc(10)β=ρb V L p L(p r w -r e +p L )2τ㊃1C g ϕ(11)式中:β为代换常数,μ为气体平均黏度,mpa.s;Z 为气体平均偏差因子㊂由于β为常数,说明页岩气的产能公式仍可采用二项式表达,只是由于解吸的作用使得拟压力差增大,产量增加㊂由于页岩气储层往往具有超低渗特征,无法真正满足拟稳态要求,实际使用过程中该产能方程易出现负斜率的现象,从而导致气井产能无法计算㊂因此,在使用该方法计算时,若出现斜率为负时,则与常规方法类似,引入修正系数C ,再继续求解,此时产能方程为三项式的形式:p 2r -p 2wf =ω1q sc +ω2q 2sc +C(12)式中:p r 为地层压力,MPa㊂在进行(p 2r -p 2wf -C )/q sc 与q sc 关系的线性回归时,首先给定C 的初值,然后通过调整C 值,使得(p 2r -p 2wf -C )/q sc 与q sc 线性相关系数最高,从而确定最终的C 值㊂2㊀产能方程可靠性分析利用上述基于致密气产能方程改进的页岩气三项式产能方程对某南川页岩气田东胜气区不同生产制度试气井的产能进行预测,确定各井产能方程,计算6口井的无阻流量为15.90ˑ104~51.81ˑ104m 3/d(表1)㊂同时,根据6口井的完井和动态监测等基础数据,应用式(5) (9)计算6口井的无阻流量为15.01ˑ104~58.00ˑ104m 3/d,计算误差为-11.95%~10.55%,说明利用三项式产能解释方法计算页岩气井无阻流量是可行的㊂由于页岩气井产能影响因素复杂,气井的地质㊁表1㊀页岩气无阻流量计算㊀140㊀特种油气藏第30卷㊀完井等参数很难准确获取,导致计算产能方程系数ω1㊁ω2较为困难㊂利用三项式页岩气井产能计算方法的优点在于,不需要直接通过产能方程系数表达式计算模型参数ω1和ω2,而利用开井超过10d的回压试井数据,通过三项式非线性回归的形式计算产能方程系数,进而计算页岩气井产能㊂应用该方法时假设了测试过程地层压力不变或变化较小,对于测试时间较短的低压㊁常压页岩气井能够满足该条件㊂对于高压页岩气井,测试期间地层压力变化较大,直接应用上述方法会产生较大偏差㊂3㊀实例应用某页岩气井(SY1HF 井)原始地层压力为52.29MPa,地层温度为109.23ħ,渗透率为3.63ˑ10-2mD,裂缝宽度为68.7m,气层的有效厚度为45.3m,裂缝条数为14条,气体密度为0.572kg /m 3,裂缝半长为86.46m,页岩密度为2.6g /cm 3,Langmuir 体积常数为1cm 3/g,Langmuir 压力常数为5.60MPa,孔隙度为0.0527,天然气压缩系数为0.0083MPa -1,表皮系数为0,解吸扩散能量补充系数为3.5㊂利用式(8)㊁(9)分别计算不同解吸附时间的系数A ㊁B ,再由式(5)计算不同解吸时间的产能,进而计算不同解吸附时间的无阻流量㊂图2为Langmuir 体积常数对不同解吸时间无阻流量的影响㊂由图2可知:相同Langmuir体积常图2㊀Langmuir 体积常数对不同时间无阻流量的影响Fig.2㊀The effect of Langmuir volume constanton open flow capacity at different time数下,随着解吸时间的延长,气井无阻流量逐渐减小,最终趋于恒定值;相同解吸时间下,Langmuir 体积常数越大,气井无阻流量越高,但随着Langmuir体积常数不断增大,同一时间气井的无阻流量增量逐渐变小㊂图3为Langmuir 压力常数对不同解吸时间无阻流量的影响㊂由图3可知:Langmuir 压力常数对气井无阻流量的影响较小;相同Langmuir 压力常数下,随着解吸附时间的延长,气井无阻流量逐渐减小,最终趋于恒定值;相同解吸附时间下,Lang-muir 压力常数越大,气井无阻流量越高,但随着Langmuir 压力常数不断增大,同一时间气井的无阻流量增量逐渐变小㊂图3㊀Langmuir 压力对不同时间无阻流量的影响Fig.3㊀The effect of Langmuir pressureon open flow capacity at different time由于页岩储层致密的天然特征,决定了不同页岩存在吸附特征的差异㊂由图2㊁3可知:当吸附时间少于10d 时,无阻流量差异很大;当吸附时间超过10d 时,无阻流量基本稳定㊂使用开井初期的测试数据所解释的无阻流量值会偏大,开井时间超过10d 后所计算的无阻流量更稳定㊂因此,计算页岩气井产能时,应采用至少开井10d 以后的测试数据㊂以SY1HF 井放喷测试为例,放喷测试不同阶段井口套压㊁日产气量和日产水量见表2(表中Ω=(p r 2-p wf 2)/q sc ),开井10d 后3种不同尺寸油嘴放喷测试曲线如图4所示㊂根据Beggs &Brill 多相管流模型计算对应测试时刻的井底流压,按照常规二项式解释的步骤,(p r 2-p wf 2)/q 作与q 的关系曲线,发现数据点并不在一条直线上㊂因此,引入修正系数C 来修正吸附气引起的附加阻力影响,形成三项式产能方程,并利用试算法回归求解产能方程系数ω1㊁ω2㊁C ㊂通过不断试算发现,当SY1HF 井C 值为28时,拟合情况最好,图5为通过试算C 值后SY1HF 井获得的产能曲线㊂利用线性回归拟㊀第3期房大志等:考虑吸附气影响的页岩气井三项式产能计算方法141㊀㊀表2㊀SY1HF放喷测试产能分析数据图4㊀SY1HF放喷测试曲线Fig.4㊀The blowout test curve of Well SY1HF合得到SY1HF井的产能方程系数ω1=0.465,ω2= 99.272,产能方程为p r2-p wf2=0.465q sc2+99.272q sc +28㊂3种不同尺寸油嘴放喷测试平均无阻流量为24.46ˑ104m3/d,与产能公式解吸附40d计算的无阻流量25.62ˑ104m3/d相比,两者相差4.5%,且曲线总体形状相近(图6),表明引入修正系数C值来修正吸附气引起的附加阻力项对IPR曲线和无阻流量的计算影响,方法具有较强的适用性㊂图5㊀SY1HF井放喷测试三项式产能曲线Fig.5㊀The trinomial deliverability curve of Well SY1HF blowout test图6㊀SY1HF井产能计算与测试解释IPR曲线对比Fig.6㊀The comparison of deliverability calculation and test interpretation IPR curves of Well SY1HF 4㊀结㊀论(1)基于致密气渗流特征,考虑页岩气的解吸扩散特征,建立了页岩气井产能模型,通过模型求解,利用钻完井和动态监测数据,得到产能方程系数和气井无阻流量㊂(2)解吸时间较短,计算无阻流量偏高;开井解吸10d后,计算的无阻流量相对可靠㊂(3)吸附气含量对页岩气井产能影响较大,吸附气含量越高,页岩气井产能越大;吸附压力对页岩气井产能影响较小㊂(4)根据开井10d后回压测试获得的产量和压力,利用页岩气井三项式产能方程计算出页岩气井产能与产能模型计算的结果偏差小于12.00%,产能计算结果相对可靠㊂参考文献:[1]DILHAN Ilk,STEPHANIE Marie Currie,DAVE Symmons,etal.Hybrid rate-decline models for the analysis of production per-formance in unconventional reservoirs[C].SPE135616,2010:1-㊀142㊀特种油气藏第30卷㊀39.[2]PETER P,VALKO W,JOHN Lee.A better way to forecast pro-duction from unconventional gas wells [C ].SPE134231-MS,2010:1-16.[3]ANH N D.An unconventional rate decline approach for tight 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２０、０６２００５２０、０７年请求豁免过程中没有充分注意
到这几年在溴代甲烷替代物研究方面所取得的进展，以及这些替代产品所具有的潜力。美加里福尼亚
洲草莓委员会主席说：它的成员单位已试用了替代物，但这里也存在一个两种产品转换的问题。
的努力，为此国际官员们于２００５年６月２７日开会商讨看多少溴代甲烷可同意美紧急应用。以及在取
评耳与Ｍａｈｅｈｍｋｔｉｓ
＆Ｃｅｎｖ目签订合同ｈｍｉｏａ
拜耳作物科学公司已与两个公司签订供给杀
代速度方面不能与其他发达国家同步的情况提起警觉。美国获溴代甲烷豁免量占给予其他发达国家豁
免量总和的６％。环保集团对美国的抱怨也得到溴７代甲烷替代物生产者道农科公司的回应。道农科公司现生产溴代甲烷替代物１３二氯丙烷和氟化硫，一
两个产品。道公司相信，国在申请紧急使用豁免权美
过程中，对它公司开发的替代物存在大量的扭曲宣传和错误认识。公司说：道由于上述情况导致美国在
使用的豁免权，如美国近三年已说服或继续说服国
际官员同意紧急使用一定数量的溴代甲烷，２０如０５
使用后能给人带来一种清新愉悦的感觉。该产品早
在２００５年已在除加外和纽约州以外的美国其他州使用。Ｐｃｒｉｉａｉｎ是拜耳８代后期开甲煽的豁免仅

美国建立杀虫剂苯氧威和硫酸脲注册审议文案

虫啉已产生了极高的抗性，对噻嗪酮的敏感性差异不酯类交换使用进行防治，但同时在吡虫啉抗性较高地区停止
大，明褐飞虱对其抗性发展比较慢。说
使用吡虫啉。
根据速灭威、嗪酮、死蜱、虫睛、虫嗪５噻毒氟噻种参考文献：药剂对黑肩绿肓蝽的室内毒性测定与田问使用质量浓度结［】庄水林．１褐飞虱对噻嗪酮及吡虫啉的抗药性研究［．Ｄ］南京：南果分析，嗪酮、灭威、虫嗪、死蜱、虫腈等噻速噻毒氟５药剂对黑肩绿肓蝽为高风险性，其中噻嗪酮相对于种但其余４农药风险性较低。种在褐飞虱的防治策略上，视抗（）飞虱水稻品种重耐褐
农药科学０管理，０６７１：２４．２０，２（）４ —４
的选育及推广应用，合理利用水稻抗性品种，做好农业防
治；强褐飞虱的预测预报，保突ｆ点、期的防加确 “重适治；做好褐飞虱抗药性的监测，是制定防治策略的重要依
防效最好，８、％，次为２％莠去津Ｓ５０ｍ／ｍ，的防除效果差异都不明显，娴嘧磺隆和氯氟吡氧乙酸为１５其３０Ｃ１０Ｌｈ且
且各处理之间差异也较为显菩；药后７ｄ除２％莠去津Ｓ混配增加了杀草范嗣，以从经济和安全的角度，，０Ｃ所宜选用
［］郭书普，时敏， ‘ ，等．旱田杂革识别与防治原色图鉴［】４应隆Ｏ＋０Ｆ２％氯氟吡氧乙酸ＥＣ

煤气灯效应英语

煤气灯效应英语The gaslighting effect is a psychological manipulation tactic that can leave victims doubting their own perceptions and memories. It's a silent form of abuse, often hidden in plain sight.This insidious practice involves a manipulator constantly questioning the victim's reality, making them feel as if they are going crazy. The term originates from a 1938 play, "Gas Light," where a husband manipulates his wife by dimming the gaslights and denying their change.In relationships, gaslighting can manifest as a partner dismissing or undermining the other's feelings, thoughts, or experiences. It's a form of control that erodes trust andself-esteem.Victims often feel isolated, as the manipulator may also discourage them from seeking support from friends or family. This tactic is designed to make the victim believe that they are unreliable and that their perceptions are flawed.Recognizing gaslighting is crucial for victims to regain control over their lives. Support from loved ones and professional help can be instrumental in overcoming the damaging effects of this psychological warfare.Educating oneself about gaslighting and its signs canempower individuals to identify and resist such manipulation. Awareness is the first step towards healing and recovery.In conclusion, the gaslighting effect is a harmful and subtle form of psychological abuse that can have long-lasting effects on a person's mental health. It's important to be vigilant and to support those who may be experiencing this form of manipulation.。

欧盟建议辉瑞公司修改戒烟药物Champix的标签

欧盟建议辉瑞公司修改戒烟药物Champix的标签
佚名
【期刊名称】《世界临床药物》
【年(卷),期】2008(29)1
【摘要】2007年12月，欧盟发表声明称，鉴于一些患者服用伐仑克林酒石酸盐（varenicline，Champix）后产生自杀念头和出现自杀倾向的情况，建议其药品生产厂商辉瑞公司修改本品的上市核准信息及产品的标签。

本品为片剂，用于成人戒烟，于2006年9月获欧盟批准上市。

【总页数】1页(P4-4)
【关键词】戒烟药物;辉瑞公司;欧盟;标签;批准上市;酒石酸盐;自杀倾向;自杀念头【正文语种】中文
【中图分类】R163;R972.4
【相关文献】
1.辉瑞戒烟药物Chantix获得成功 [J], 岳海霏（编译）
2.加拿大卫生部修改Champix的标签 [J], 范丽珠（摘）
3.FDA表示辉瑞戒烟药物可致心脏病等 [J],
4.辉瑞公司的戒烟药物Chantix获得FDA批准 [J],
5.新型戒烟药物Champix在加拿大上市 [J],
因版权原因，仅展示原文概要，查看原文内容请购买。

色氨酸在普鲁士蓝修饰玻碳电极上的电化学行为研究

色氨酸在普鲁士蓝修饰玻碳电极上的电化学行为研究蔡卓;莫丽君;卢登峰;张娴;甘静妮【摘要】采用电沉积法制备了普鲁士蓝修饰玻碳电极(PB/GCE),使用循环伏安法(CV)研究了色氨酸(Trp)在修饰电极上的电化学特性,并建立了一种电化学检测色氨酸的新方法.实验结果表明,在优化实验条件下,色氨酸在8.0×10-6 ～5.0×10-4 mol·L-1浓度范围内与峰电流呈良好线性关系,线性回归方程为Ip(μA)＝5.8954c(μmol·L-1)-32.91,相关系数r＝0.999 9(n=8),方法检出限(S/N=3)为3.5×10-7 mol·L-1.将该修饰电极用于色氨酸样品的测定,结果满意.初步的反应机理探讨表明,色氨酸在普鲁士蓝电极上的反应可能是以两步进行的两电子氧化过程.【期刊名称】《分析测试学报》【年(卷),期】2010(029)011【总页数】5页(P1132-1136)【关键词】色氨酸;普鲁士蓝;玻碳电极【作者】蔡卓;莫丽君;卢登峰;张娴;甘静妮【作者单位】广西大学,化学化工学院,广西,南宁,530004;广西大学,化学化工学院,广西,南宁,530004;广西大学,化学化工学院,广西,南宁,530004;广西大学,化学化工学院,广西,南宁,530004;广西大学,化学化工学院,广西,南宁,530004【正文语种】中文【中图分类】O657.1;TQ464.7色氨酸是人体必需的氨基酸,主要依靠外界的摄取来满足身体需求。

人体如果缺乏色氨酸会影响脑的正常代谢及脑部的发育。

色氨酸在食品、饲料以及医疗等行业中有着广泛的应用。

色氨酸作为药物具有治疗失眠、抑郁、躁狂等症状及止痛的效果[1]。

静脉注射 L-色氨酸制剂后可使癌症患者精神得到改善[2],同时也可以使严重的帕金森氏症患者出现的情感障碍、精神错乱、幻觉等症状得到缓解[1]。

目前测定色氨酸的方法有高效液相色谱法、紫外光谱法、荧光光谱法等[3-6],但这些方法样品处理过程繁琐。