Effect of Al2O3 Binder on the Precipitated Iron-Based Catalysts for Fischer-Tropsch Synthesis

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蓄电池技术手册中英文版

● Portable TV, pickup camera, radio and tape recorder.●电动工具、割草机、吸尘器。

●Electric tool, field mower. Vacuum cleaner.●照相机、新闻摄影设备。

●Camera, news photography equipment.●便携式个人计算机、语言处理器、终端。

●Portable personal computer, language processor, terminal.●野外测试设备、医疗仪器设备。

●Outdoor testing equipment, medical instrument equipment.●移动电话机、对讲机。

●Mobile phone, walkie-talkie.●矿灯、割胶灯、应急灯、铁路信号灯。

●Lamp, tapping lamp, emergency light, railway signal light.●电动玩具、电动轮椅。

●Electric toy, electric wheel chair.3 电池结构Structure of the battery图1.蓄电池结构(12V系列) Fig.1 structrue of the storage battery (12V series)图2.蓄电池结构(2V系列) Fig.2 structrue of the storage battery (2V series)表1 SUPER FM GFM 系列蓄电池构件与功能Table.1 SUPER FM GFM series storage battery component and its function部件结构材料功能battery to be 13.5V. While float charge saturation state reaches, float charge current shall be generally 2-4mA for each AH, whose charging feature shown as Fig.5.浮充电压应根据温度变化进行调整，其校正系数K为-3mV/℃即Float charge voltage must be regulated in accordance with variation of temperature, herein ,calibrating coefficient K is -3mv/℃Vt=V25+K(t-25)具体选择可按图6进行。

氧化铁对铂在碱性介质中催化氧化甲醇的促进作用(英文)

Article
Promoting effects of Fe2O3 to Pt electrocatalysts toward methanol oxidation reaction in alkaline electrolyte
Guihua Song, Haifang Yang, Yafei Sun, Jingyi Wang, Weidong Qu, Qiang Zhang, Lingjuan Ma, Yuanyuan Feng *
Chinese Journal of Catalysis 38 (卷第3期 |
available at
journal homepage: /locate/chnjc
Key Laboratory of Life‐Organic Analysis, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, China
A R T I C L E I N F O
1. Introduction Direct methanol fuel cells (DMFCs) show great potential as future power sources for automobile power and portable elec‐ tronic devices owing to a number of advantages, such as the low operating temperature (< 100 °C), high energy efficiency, convenient transportation, low environmental pollution and fast start‐up time [1]. To date, the noble metal Pt is still the most active catalyst material both for the anodic and cathodic reactions of DMFCs and cannot be completely replaced by other base metals. Owing to the high cost of Pt, the commercial ap‐ plication of DMFCs has been limited. In addition, Pt is easily poisoned by the CO‐like intermediates in the process of the methanol electro‐oxidation reaction (MOR). The intermediates adsorb on the surface of Pt atoms, resulting in a significant de‐ crease in the catalytic performance of Pt, which further in‐ creases the cost of DMFCs. Over the past decades, a number of studies have focused on the investigation of Pt‐free electrocatalysts or the modification of Pt catalysts [2,3]. The traditional modification was accom‐ plished through the addition of other components or promot‐ ers. The components themselves exhibit no catalytic activity toward the reactions but can promote the activity of Pt during catalysis. It is well known that the addition of Ru to Pt catalysts

水化热抑制剂对水泥-粉煤灰胶凝材料水化和混凝土性能的影响

第49卷第8期2021年8月硅酸盐学报Vol. 49，No. 8August，2021 JOURNAL OF THE CHINESE CERAMIC SOCIETY DOI：10.14062/j.issn.0454-5648.20200724 水化热抑制剂对水泥-粉煤灰胶凝材料水化和混凝土性能的影响陈炜一1，周予启1,2，李嵩2，阎培渝1(1. 清华大学土木工程系，北京 100084；2. 中建一局集团建设发展有限公司，北京 100102)摘要：探究了水化热抑制剂(TRI)对水泥-粉煤灰胶凝材料水化过程和混凝土性能的影响。

通过改变粉煤灰在胶凝材料中的占比和水化热抑制剂的掺量，观察了胶凝材料的水化过程以及混凝土的绝热温升、力学性能和干燥收缩特性。

胶凝材料的水化热测试结果表明，在含有粉煤灰的胶凝材料中，水化热抑制剂降低胶凝材料的放热速率峰值、延后放热峰出现时间的作用更加明显。

硬化浆体的相组成和微观结构测试表明，水化热抑制剂对胶凝材料水化程度的抑制主要发生在7d前。

混凝土试验结果表明，水化热抑制剂会放缓混凝土的绝热温升速率，降低粉煤灰混凝土的早期强度并增加干燥收缩。

关键词：水化热抑制剂；粉煤灰；胶凝材料；混凝土；水化；强度中图分类号：TU528.45 文献标志码：A 文章编号：0454–5648(2021)08–1609–10网络出版时间：2021–06–18Impact of Temperature Rising Inhibitor on Hydration of Cement-Fly Ash CementitiousMaterials and Performance of ConcreteCHEN Weiyi1, ZHOU Yuqi1,2, LI Song2, YAN Peiyu1(1. Department of Civil Engineering, Tsinghua University, Beijing 100084, China;2. China Construction First Division Group Construction & Development Co. Ltd, Beijing 100102, China) Abstract: Effect of temperature rising inhibitor (TRI) on the hydration process of cementitious materials containing fly ash and the performance of concrete was investigated. The hydration process of cementitious materials was examined as a function of the contents of fly ash and TRI. The adiabatic temperature rise, mechanical properties and drying shrinkage of concrete derived from the cementitious materials and TRI were also evaluated. According to the hydration heat of the binder pastes, it was revealed that the addition of TRI lowers and delays the exothermic peaks more significantly in the presence of fly ash. The phase composition and microstructure of the hardened paste indicate that TRI mainly inhibits the hydration degree of the cementitious materials in the first 7 days. The presence of TRI slows down the adiabatic temperature rising rate, reduces the early strength of the concrete and increases drying shrinkage of the concrete.Keywords: temperature rising inhibitor; fly ash; cementitious materials; concrete; hydration; strength温度裂缝是混凝土结构中最常出现的裂缝类型。

合金粘度的影响英文文献

合金粘度的影响英文文献
以下是关于合金粘度的影响的英文文献：
1. Saito, H., et al. "Effects of alloying elements on the viscosity of liquid Fe-based alloys." Journal of Non-Crystalline Solids 357.1 (2011): 47-53.
2. Wang, J., et al. "Influence of alloying elements on the viscosity of liquid Al-Cu alloys." Transactions of Nonferrous Metals Society of China 22.7 (2012): 1567-1572.
3. Anwar, Hafeez, et al. "Effect of alloying elements on the viscosity of liquid Ni-based alloys." Journal of Applied Physics 106.11 (2009): 113519.
4. Zhang, H., et al. "The effect of alloying elements on the viscosity of liquid Sn-Bi alloys." Journal of Alloys and Compounds 787 (2019): 1110-111
5.
这些文献研究了不同合金元素对合金粘度的影响，提供了相关的实验结果和分析。

您可以通过登录相关数据库或与学术机构进行文献检索以获取更多详细信息。

Effects of CaCO3 on slag flow properties at high temperatures-译文

高温条件下CaCO3 对炉渣流动特性的影响摘要通过添加不同量的CaCO3来对选定的煤灰进行试验，以理解对包括煤灰熔点、炉渣粘度、临界粘度时的温度和炉渣类型等流动特性的影响。

我们应用了ICP-AES、XRD 和FTIR 的分析方法来确定炉渣的成分和结构。

我们还应用了化学热力学软件Factsage 来计算SiO2 —Al2O3 —CaO—FeO 系统的液相温度并预测会形成的矿物质以及固相的比例作为温度的函数。

结果表明，由化学热力学软件Factsage 计算出的液相线温度能很好地预测煤灰熔点温度的变化。

炉渣粘度会随着添加的CaCO3 的量的变化而增加，这是因为固相的形成过程不同。

傅里叶变换红外(FTIR) 光谱表明，Ca2 + 会导致将聚合的Si — O — Si 破坏成Si-O的结构，所以子炉渣中增加Ca2 + 中会导致高于液相线温度的粘度降低，当低于液相线温度时，固形物含量会随着在临界粘度(Tcv) 温度以上的CaCO3 的增加而减少。

同时，我们发现固体颗粒形成的速率与Tcv相关并基于此发现提出了新的预测Tcv的方法。

此外，利用x射线衍射分析推测出了炉渣的类型与添加CaCO3 的量有关。

我们希望对煤灰熔融温度、Tcv 和炉渣类型的预测来作为对于适合排渣气化技术的添加助熔剂以规范煤灰特性的参考。

关键词CaCO3;煤灰融化温度;炉渣粘度;临界粘度温度;炉渣类型1.引言对未来电力发电和化工生产的高效率的需求导致了对IGCC 技术的关注度的增加，特别是在先进的煤气化技术例如气流床气化炉等。

在气化炉中，在高于1400° C的高温度下和强气流的作用下，煤中的有机物质会在短时间内完全燃烧并气化，并且煤中的矿物质会变成煤灰。

煤灰会变成液体炉渣是由于在高温下其组分中的矿物质融化并相互反应的结果。

对于带有液态炉渣去除过程的气流床气化炉而言，炉渣流动特性比煤中的有机质的转换更为重要。

连续排渣对于不同气流的气化炉的成功操作非常重要（GE、Shell、Prenfflol、GSP、Texco、Eagle等不同的品牌的气化炉），所以在高温下炉渣的流动性能以及添加剂对他们的影响具有非常重要的意义。

颗粒稳定泡沫法制备莫来石基多孔陶瓷的结构与性能

n(Al):n(Si)
2.0:1.0 2.2:1.0 2.4:1.0 3.0:1.0 n—Mole.
表 1 实验参量设计 Table 1 Experimental parameters
Solid content Gelatin addition PG addition (accounting for (account-ing for (accounting for total volume)/% solid mass)/% alumina mass)/%
资助。第一作者：王涵(1994—)，女，硕士研究生。通信作者：李翠伟(1973—)，女，博士，教授。
Received date: 2019–07–17. Revised date: 2019–08–18. First author: WANG Han (1994–), female, Master candidate. E-mail: 17121355@ Correspondent author: LI Cuiwei (1973–), female, Ph.D., Professor. E-mail: cwli@
· 826 ·
《硅酸盐学报》 J Chin Ceram Soc, 2020, 48(6): 824–832
2020 年
图 1 颗粒稳定泡沫法制备莫来石基多孔陶瓷工艺流程图 Fig. 1 Flow chart for preparation of mullite-based porous ceramics by particle-stabilized foaming method
Keywords: mullite; porous ceramics; particle-stabilized; freeze drying; thermal conductivity

211171484_La1-xSrxMnO3钙钛矿涂层的抗结焦性能

化工进展Chemical Industry and Engineering Progress2023 年第 42 卷第 4 期La 1−x Sr x MnO 3钙钛矿涂层的抗结焦性能梁贻景，马岩，卢展烽，秦福生，万骏杰，王志远（上海市动力工程多相流动与传热重点实验室，上海理工大学能源与动力工程学院，上海 200093）摘要：目前，钙钛矿材料在汽车尾气催化处理、污水处理及燃料电池等方面应用广泛，但在抑制热裂解结焦涂层应用方面鲜有报道。

本文以磷酸二氢铝为黏结剂，采用浆料法在HP40不锈钢基体表面制备了La 1−x Sr x MnO 3钙钛矿涂层，采用X 射线衍射（XRD ）、扫描电子显微镜（SEM ）、能谱仪（EDS ）和Raman 光谱考察了La 1−x Sr x MnO 3钙钛矿涂层及表面焦层的物相组成和微观结构，利用X 射线光电子能谱（XPS ）研究了涂层组成元素的化学状态，通过石脑油热裂解结焦实验评价了涂层的抗结焦效果。

结合材料表征与实验结果，阐述了涂层抗结焦机理。

表征结果显示，La 1−x Sr x MnO 3钙钛矿涂层涂覆均匀，厚度约为30μm ，与基底贴合紧密，粒子之间结合较好，但表面存在少量微孔；La 1−x Sr x MnO 3钙钛矿氧化物具有明显的立方晶体特征，Sr 进入LaMnO 3晶格未改变钙钛矿晶相结构；与未经掺杂的LaMnO 3涂层相比，Sr 掺杂后的钙钛矿表面吸附氧含量与晶格氧含量之比O ads /O latt 更高，而且涂层中氧空位的数量增加。

热裂解结焦实验结果表明，钙钛矿涂层的抗结焦性能随着Sr 含量的提高而增强，当裂解时间为3h 和5h 时，La 0.2Sr 0.8MnO 3涂层的抑制结焦效果分别可达到84.88%和82.31%。

钙钛矿涂层结构不仅通过屏蔽基底金属的催化活性抑制了催化结焦过程，还通过催化焦炭氧化燃烧反应进一步减少热裂解焦炭的沉积。

其中，Sr 的掺杂可促进氧空位形成，增加氧的流动性，从而促进电子转移，进一步提高催化焦炭燃烧反应的活性。

羟丙基甲基纤维素含量对塑性成型陶瓷生坯强度的影响

第６期收稿日期：２０２１－０２－２５基金项目：阜阳市－阜阳师范大学校地横向合作项目（ＸＤＨＸ２０１７１７）；博士科研启动项目（２０１６ＫＹＱＤ０００６）；阜阳师范大学青年人才重点基金项目（ｒｃｘｍ２０２００５，ｒｃｘｍ２０２００３）；安徽省高校自然科学研究项目（ＫＪ２０２０Ａ０５４６，ＫＪ２０２０Ａ０５２５０）作者简介：姜广鹏（１９８０—），安徽阜阳人，博士后，讲师，研究方向：多孔陶瓷。

羟丙基甲基纤维素含量对塑性成型陶瓷生坯强度的影响姜广鹏，刘雪艳，张琳，陶栋梁，罗春华，王永忠（阜阳师范大学化学与材料工程学院，安徽阜阳　２３６０３７）摘要：生坯强度对于陶瓷的后续加工操作有着重要的意义，但目前对塑性成型生坯强度的研究还很少。

本文以羟丙基甲基纤维素（ＨＰＭＣ）作为陶瓷粉料的有机粘结剂，通过加入不同量ＨＰＭＣ和水进行塑性成型，对烘干后生坯气孔率，抗弯强度和断口显微形貌进行了研究。

结果发现，高剪切力的轮碾可使ＨＰＭＣ和水混合成膜覆盖在氧化铝颗粒表面。

随着ＨＰＭＣ含量增加，气孔率先降低后增加，在加入量为１５％时达到最低值，气孔率为４５％。

抗弯强度随ＨＰＭＣ含量增加先增加后降低，当ＨＰＭＣ添加量为２５％时，生坯强度最高为７．５ＭＰａ，是ＨＰＭＣ添加量为５％（１．６ＭＰａ）时的４．７倍。

关键词：粘结剂；生坯；抗弯强度；显微结构中图分类号：ＴＯ１７４．７５＋８．１１文献标识码：Ａ文章编号：１００８－０２１Ｘ（２０２１）０６－００２３－０３ＥｆｆｅｃｔｏｆＨｙｄｒｏｘｙｐｒｏｐｙｌＭｅｔｈｙｌＣｅｌｌｕｌｏｓｅＣｏｎｔｅｎｔｏｎｔｈｅＧｒｅｅｎＳｔｒｅｎｇｔｈｏｆＰｌａｓｔｉｃＦｏｒｍｅｄＣｅｒａｍｉｃＢｏｄｙＪｉａｎｇＧｕａｎｇｐｅｎｇ，ＬｉｕＸｕｅｙａｎ，ＺｈａｎｇＬｉｎ，ＴａｏＤｏｎｇｌｉａｎｇ，ＬｕｏＣｈｕｎｈｕａ，ＷａｎｇＹｏｎｇｚｈｏｎｇ（ＣｏｌｌｅｇｅｏｆＣｈｅｍｉｓｔｒｙａｎｄＭａｔｅｒｉａｌＥｎｇｉｎｅｅｒｉｎｇ，ＦｕｙａｎｇＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｆｕｙａｎｇ　２３６０３７，Ｃｈｉｎａ）Ａｂｓｔｒａｃｔ：Ｔｈｅｇｒｅｅｎｓｔｒｅｎｇｔｈｉｓｏｆｇｒｅａｔｓｉｇｎｉｆｉｃａｎｃｅｔｏｔｈｅｓｕｂｓｅｑｕｅｎｔｐｒｏｃｅｓｓｉｎｇｏｐｅｒａｔｉｏｎｓｏｆｃｅｒａｍｉｃｓ，ｂｕｔｔｈｅｒｅａｒｅｆｅｗｓｔｕｄｉｅｓｏｎｔｈｅｇｒｅｅｎｓｔｒｅｎｇｔｈｏｆｐｌａｓｔｉｃｆｏｒｍｉｎｇ．Ｉｎｔｈｉｓｐａｐｅｒ，ｈｙｄｒｏｘｙｐｒｏｐｙｌｍｅｔｈｙｌｃｅｌｌｕｌｏｓｅ（ＨＰＭＣ）ｉｓｕｓｅｄａｓｔｈｅｏｒｇａｎｉｃｂｉｎｄｅｒｏｆｃｅｒａｍｉｃｐｏｗｄｅｒ，ａｎｄｐｌａｓｔｉｃｍｏｌｄｉｎｇｉｓｃａｒｒｉｅｄｏｕｔｂｙａｄｄｉｎｇｄｉｆｆｅｒｅｎｔａｍｏｕｎｔｓｏｆＨＰＭＣａｎｄｗａｔｅｒ，ａｎｄｔｈｅｐｏｒｏｓｉｔｙ，ｂｅｎｄｉｎｇｓｔｒｅｎｇｔｈａｎｄｆｒａｃｔｕｒｅｍｏｒｐｈｏｌｏｇｙｏｆｔｈｅｇｒｅｅｎｂｏｄｙａｆｔｅｒｄｒｙｉｎｇｓｔｕｄｉｅｄ．Ｉｔｗａｓｆｏｕｎｄｔｈａｔｈｉｇｈ－ｓｈｅａｒｗｈｅｅｌｍｉｌｌｉｎｇｃａｎｍｉｘＨＰＭＣａｎｄｗａｔｅｒｔｏｆｏｒｍａｆｉｌｍｃｏｖｅｒｉｎｇｔｈｅｓｕｒｆａｃｅｏｆａｌｕｍｉｎａｐａｒｔｉｃｌｅｓ．ＡｓｔｈｅｃｏｎｔｅｎｔｏｆＨＰＭＣｉｎｃｒｅａｓｅｓ，ｔｈｅｐｏｒｏｓｉｔｙｆｉｒｓｔｄｅｃｒｅａｓｅｓａｎｄｔｈｅｎｉｎｃｒｅａｓｅｓ，ｒｅａｃｈｉｎｇｔｈｅｌｏｗｅｓｔｖａｌｕｅｗｈｅｎｔｈｅａｄｄｅｄａｍｏｕｎｔｉｓ１５％，ａｎｄｔｈｅｐｏｒｏｓｉｔｙｉｓ４５％．ＴｈｅｆｌｅｘｕｒａｌｓｔｒｅｎｇｔｈｆｉｒｓｔｉｎｃｒｅａｓｅｓａｎｄｔｈｅｎｄｅｃｒｅａｓｅｓｗｉｔｈｔｈｅｉｎｃｒｅａｓｅｏｆＨＰＭＣｃｏｎｔｅｎｔ．ＷｈｅｎｔｈｅＨＰＭＣａｄｄｉｔｉｏｎａｍｏｕｎｔｉｓ２５％，ｔｈｅｇｒｅｅｎｓｔｒｅｎｇｔｈｉｓｔｈｅｈｉｇｈｅｓｔ７．５ＭＰａ，ｗｈｉｃｈｉｓ４．７ｔｉｍｅｓｔｈａｔｗｈｅｎｔｈｅＨＰＭＣａｄｄｉｔｉｏｎａｍｏｕｎｔｉｓ５％（１．６ＭＰａ）．Ｋｅｙｗｏｒｄｓ：ｂｉｎｄｅｒ；ｇｒｅｅｎｂｏｄｙ；ｓｔｒｅｎｇｔｈ；ｍｉｃｒｏｓｔｒｕｃｔｕｒｅ在陶瓷制品的生产中，通常希望在烧结前具有尽可能高的生坯强度，因为陶瓷生坯经常在烧结前进行处理和机械加工，生坯强度不足可能会损坏生坯［１－４］。

碳纤维的电学性能英文版

Electrical Conductivity of the Carbon FiberConductive ConcreteHOU Zuofu 1,2, LI Zhuoqiu 1*, WANG Jianjun 1(1.School of Sciences, Wuhan University of Technology, Wuhan 430070, China; 2. Department of Mechanical Engineering, Yangtze University, Jingzhou 434023, China)Abstract: This paper discussed two methods to enhance the electrical conductivity of the carbon ﬁ ber(CF) electrically conductive concrete. The increase in the content of stone and the amount of water used to dissolve the methylcellulose and marinate the carbon ﬁ bers can decrease the electrical resistivity of the electrically conductive concrete effectively. Based on these two methods, the minimum CF content of the CF electrically conductive concrete for deicing or snow-melting application and the optimal ratio of the amount of water to dissolve the methylcellulose and marinate the carbon ﬁ bers were obtained.Key words: carbon ﬁber; electrical resistivity; conductive concreteDOI 10.1007/s11595-005-2346-x1 IntroductionCF electrically conductive concrete is a newtype of concrete made by adding carbon fibers into conventional concrete. After adding the carbon ﬁ bers, the electric resistivity of concrete can reduce to a necessary value for various applications such as self-monitoring [1], electromagnetic interference shielding [2], thermistor [3], lateral guidance in automatic highways [4], traffic monitoring and weighing in motion [5], deicing or snow-melting [6-11],etc . For example, the conductive concrete mixture containing 0.73% carbon fibers (by volume) and 20% silica fume(SF) has a good electrical conductivity and a superior mechanical strength when the ratio of cement to sand to stone is 1 1 1[12]. But in practical application, the price of conventional concrete can be decreased effectively by increasing the content of the sand and stone. At the same time, the rational content of the coarse aggregates can also enhance the mechanical properties of the hardened concrete. Reza et al had discussed the effect of the water-cement and sand-cement ratio on the electrical resistivity of CF reinforced mortar [13]. But the effect of the stone-cement ratio on the electrical resistivity is uncertain. Accordingly, the the properties of the electrically conductive concrete was discussed in this paper.Furthermore, in order to disperse the carbon fibers effectively, methylcellulose must be dissolved in water at ﬁ rst. Then carbon ﬁ bers and defoamer were added into water and stirred. It is found that the amount of water in this stage affects the final electrical resistivity of the conductive concrete and there is no report dealing with this problem.2 Experimental2.1 Materials and specimensCarbon ﬁ bers of 7 μm in diameter and 5-10 mm in nominal length were used as the conductive filler. The carbon fibers were isotropic PAN-based and unsized. Other properties of CF are given in Table 1. SF, a by-product in the manufacture of ferro-silicon, was used as fiber dispersant. The chemical compositions and granularities of SF are given in Table 2. Methylcellulose was used as primary dispersant in the amount of 0.4 % by weight of binder (cement + SF). Standard river sand was used as fine aggregates, defoamer was added to accompany methylcellulose. The defoamer-cement ratio was 0.14% (by volume). The ratio of the high-range water-reducing agent to cement was 1% (by weight). The water-cement ratio was 0.55-0.60 (by weight) for CF conductive concrete and 0.45 for plain concrete, respectively.The thickness of all samples was 40 mm in the tests. Obviously, it is unsuitable to adopt coarse aggregateswas 15 mm, the smallest stone size was 5 mm, and the average stone size was 12 mm. The dimensions of the compressive specimens were 40 mm×40 mm×40 mm. The three points flexural tests were conducted using 160 mm×40 mm×40 mm bar specimens. The loading speed was 454 kg/min. Four specimens of each group were tested. The dimensions of the specimens for the electrical resistance measurement was 160 mm×130 mm×40 mm, three specimens of each group were tested.2.2 Electrode con ﬁ gurationElectrode configuration is a very important aspect in the making of electrically conductive concrete for deicing or snow-melting. The electrode must be laid in the concrete and it must be protected from rusting. Therefore, the 0.3 mm thick perforated stainless steel strip was used as the electrode. The diameter of the holes must be greater than or equal to the maximum aggregate size of 15 mm to allow concrete to ﬂ ow through to ensure a good bond between the electrode and the concrete. 2.3 Mixing procedureMethylcellulose was first added into water while stirring and left for approximately 20 min. to allow it to dissolve completely. Carbon fibers and defoamer were then added into water and stirred gently. The rest of the mixing water was poured into the mixer followed by the high-range water-reducing agent. Then the cement and SF were added and stirred by a rotary mixer for 3 min. The mixer was stopped and the carbon ﬁ bers were poured into the mixer. When the mixer was run for 1 min, the sand was added and stirred for 3 min. Finally the stones were added and stirred for 3 min. After the mixture was poured into an oiled mold, the electrode (if applicable) was laid in fresh concrete. Then an external vibrator was used to facilitate compaction and decrease the amount of air bubbles. The samples were demolded after 24 hours and then cured at room temperature (temperature: +25℃; relative humidity: 70%).2.4 The electrical resistance measurementIn general, the four-probe method is found to be an effective method for measuring the volume electricalresistivity of the concrete samples. As the CF conductive concrete being discussed in this paper will be used in deicing or snow-melting, the electrode will be embedded in the concrete and the two-probe method will be used to determine the output power in practical application. Moreover, the contact resistance can also generate heat when the conductive concrete is connected to a power source. So it is unnecessary to distinguish the contact resistance from the total electrical resistance in this paper. Therefore, the electrical resistance measurements in this paper were all conducted using the two-probe method.If the electrical resistivity of CF conductive concrete used in deicing or snow melting is high, it will not generate heat effectively. Yehia et al illustrated that the electrical resistivity must be lower than 103 Ω·cm for the deicing application [11]. This paper suggests the threshold must be lower than 102 Ω·cm to ensure the CF conductive concrete generates heat effectively with 36 V safe voltage.3 Results and Discussion3.1 The influence of the ratios of cement to sand to stoneAccording to the previous study, the electrical resistivity of the conductive concrete mixture containing 0.73% carbon fibers (by volume) and 20% SF when the ratio of cement to sand to stone is 1 1 1 can meet the requirement for deicing or snow-melting [12]. Based on this result, four kinds of mixture that maintained the w /c at 0.55-0.58 and the ﬁ ber volume at 0.73% (adding 20% SF) were designed and studied when the ratios of cement to sand to stone were 1 1 1, 1 2 1, 1 1 2, 1 2 2, respectively. All tests were taken after 28 days. The results are listed in Table 3.Table 3 Effects of different ratios on properties of CF conductive concreteProperties The ratio of cement to sandto stone(by weight)1:1:11:2:11:1:21:2:2Electrical resistivity /(Ω·cm)85.90579.0038.30210.30Flexural strength /MPa 5.69 5.10 5.81 3.19Compressive strength /MPa 44.70 41.5039.90 33.80As shown in Table 3, the electrical resistivity for the ratio of 1 1 2 is the lowest among the four mixtures. In other words, a proper increase of stone can decrease the electrical resistivity. Because the CF content was held constant, the increase of stone will lead to a more accumulation of CF in the matrix. Thus the matrix resistivity will decrease and lead to an overall decrease of the composite resistivity. Although a proper additionTable 1 Properties of CFTensile strength Tensile Density Electrical Content of /MPa modulus/GPa /(g/cm 3) resistivity/(μΩ·m) carbon/ % 2000-3000 175-215 1.74-1.77 30 =93Table 2 Chemical compositions and granularities of SF Chemical compositions SiO 2 Al 2O 3 MgO CaO Fe 2O 3 ig. loss Percent/% 91-93 0.98-0.2 0.9-0.2 0.47 0.15-1.6 2.0-5.0Particle size/μm 10 1-10 0.5-1 0.1- 0.5 <0.1Percent/% 2.3 8.6 14.2 61.5 11.3of the sand can enhance the electrical conductivity of the carbon fiber cement-based composites[14], but when the sand-cement ratio increases up to 2, the composite resistivity will obviously increase. That is to say, the excessive sand affects the formation of the carbon ﬁ ber networks and then leads to an increase in the composite resistivity. This result is also consistent with the result of Reza’ s study[13]. The ﬂ exural strength and compressive strength decrease with the increase of the sand-cement and stone–cement ratio because the increase of the aggregates will lead to a higher CF content in the matrix and increase the amount of air bubbles in the matrix. At the same time, the increase of the sand-cement and stone–cement ratio will also result in the decrease of the amount of cement in an unit volume of concrete and also affect the ﬁ nal ﬂ exural strength and compressive strength.Summing up the four ratios in the Table 3, at a certain CF content, when the ratio of cement to sand to stone is 1 1 2 (by weight), the properties of the CF conductive concrete are the best as a whole, with the exception of a slight decrease in compressive strength.Based on the aforementioned analysis, a further study was finished and the minimum CF content of the CF electrically conductive concrete for deicing or snow-melting was obtained. As seen in Fig.1, while the ratio of cement to sand to stone is 1 1 1, the electrical resistivity of the CF conductive concrete with 0.73% carbon ﬁ bers can be reduced to 100 Ω·cm after regarding the size effect[13]. That is to say, 0.73% CF content can meet the lowest requirement for deicing or snow-melting application. But while the ratio of cement to sand to stone is increased to 1 1 2, the CF content can be reduced to about 0.58%.3.2 The influence of the amount of water in the beginning stageAlthough the water-cement ratio does not have a signiﬁ cant effect on the electrical resistivity at a high CF content[13], but it was observed that the amount of water used to dissolve the methylcellulose and marinate the carbon fibers in the beginning stage affected the final electrical resistivity when the water-cement ratio was held constant. Three mixture designs with the water-cement ratio at 0.58, the ﬁ ber volume at 0.58% and the ratio of cement to sand to stone at 1 1 2 were studied, while the ratio of the amount of water in the beginning stage to the total amount of water was 0.43, 0.57 and 0.71, respectively.As seen in Fig.2, there is a decrease in the electrical resistivity with the increasing water in the beginning stage. For example, when the ratio varies from 0.43 to 0.57, the electrical resistivity has a decrease of 40.1%. Of course, when the ratio varies from 0.57 to 0.71, there is only a slight decrease in the electrical resistivity. It is concluded that the large amount of water in the beginning stage improves the dispersion of the carbon ﬁ bers when the ﬁ ber volume and water-cement ratio are held constant. But while the percentage of the amount of water in the beginning stage is high enough to saturate the carbon fibers sufficiently, this effect is neglectable. So there is an optimal ratio of the amount of water in the beginning stage to the total amount of water in the making of CF electrically conductive concrete. In this paper, this ratio is presumed to be 0.6-0.7.4 ConclusionsThe conductive concrete mixture containing 0.58% CF (by volume) and 20% SF shows a good electrical conductivity and a superior mechanical strength while the ratio of cement to sand to stone is increased to 1 1 2. Furthermore, increasing the percentage of water used to dissolve the methylcellulose and marinate the carbon fibers in the beginning stage can also improve the dispersion of the carbon ﬁ bers and then enhance the electrical conductivity of the CF electrically conductive concrete. In this paper, 60%-70% of the total water was suggested to be used to marinate the carbon fibers inthe beginning stage. These two methods can reduce thevolume fractions of CF and then decrease the cost of the CF electrically conductive concrete for deicing or snow-melting.References[1] M Chiarello, R Zinno. Electrical Conductivity of Self-monitoringCFRC[J]. Cement & Concrete Composites, 27(2005): 463-469 [2] X L Fu, D D L Chung. Submicron Carbon Filament Cement-MatrixComposites for Electromagnetic Interference Shielding[J]. Cem.Concr. Res., 1996, 26(10):1467-1472[3] S H Wen, D D L Chung. Carbon Fiber-Reinforced Cement asa Thermistor[J]. Cement and Concrete Research, 1999, 29(6):961-965[4] X.L Fu, D D L Chung. Radio-Wave Reﬂ ecting Concrete for LateralGuidance in Automatic Highways[J]. Cement and Concrete Research, 1998, 28(6): 795-801[5] Z Q Shi, D D L Chung. Carbon Fiber Reinforced Concrete forTrafﬁ c Monitoring and Weighing in Motion[J]. Cem. Concr. Res., 1999, 29(3):435-439[6] P Xie, J J Beaudoin. Electrically Conductive Concrete and ItsApplication in Deicing. Advances in Concrete Technology[C].In:Proceedings. Second CANMET/ACI International Symposium, SP-154, American Concrete Institute, Farmington Hills, Mich., 1995:399-417[7] C Y Tuan. Electrical Resistance Heating of Conductive ConcreteContaining Steel Fibers and Shavings[J]. ACI Materials Journal, 2004, 101(1): 65-71[8] C Y Tuan, S Yehia. Evaluation of Electrically Conductive ConcreteContaining Carbon Products for Deicing[J]. ACI Materials Journal, 2004, 101(4): 287-293[9] S Yehia, C Y Tuan. Conductive Concrete Overlay for Bridge DeckDeicing[J]. ACI Materials Journal, 1999, 96(3):382-390[10] S Yehia, C Y Tuan. Thin Conductive Concrete Overlayfor Bridge Deck Deicing and Anti-icing[J]. Journal of the Transportation Research Board, Material and Construction, Concrete 2000, No.1698, Transportation Research Council, Washington D C, 45-53[11] S Yehia, C Y Tuan, D Ferdon and Bing C. Conductive ConcreteOverlay for Bridge Deck Deicing: Mixture Proportioning, Optimization and Properties[J]. ACI Materials Journal, 2000, 97(2):172-181[12] Z F Hou, Z Q Li, S L Hu, et al. Inﬂ uence of Silica Fume onProperties of Carbon Fiber Electrically Conductive Concrete[J].Concrete. 2003, 160(2):26-28[13] F Reza, G B Batson, J A Yamamuro, et al. V olume ElectricalResistivity of Carbon Fiber Cement Composites[J]. ACI Materials Journal, 2001, 98(1):25-35[14] P W Chen, D D L Chung. Improving the Electric Conductivityof Composites Comprised of short Carbon Fiber in a Nonconducting Particulate Filler[J]. J. of Electronic Mat., 1995, 24(1):47-51。

骨料中二氧化硅含量对混凝土强度的影响

中分，加
了过渡区内的和。了 ITZ的结
构，学者从的骨料度、、
对
混凝土的影响两，近
骨料表面粗度和
性
'7-9*,
ITZ的结构和性能。些研究是
基分不同骨料的界面结
和用用外加
的
者化学
界面结，
界面过渡区
的性能的一研究 < 从骨料组成的成分，
2 在混凝土水化过中，能有与过渡区中的Ca（OH）
本试验水泥选用基准水泥P-I 42.5，产自中联集团山东
鲁城水泥有司，化学成分分表1<
磨细 :S95 渣粉，产河北三河天龙矿粉
有限公司,比表面积440 m2/kg，密度为2 800 kg/m3，需水
量比为96%。
煤：I级粉煤，产自于山东华能德州电力实业总
公司，需水比94%，烧失量4.3%。
粗骨料：、
结，从
界面过渡区的结构，面的研究，
<_______
收稿日期：2018-09-04
基金项目：国家自然科学基金项目（51678049）
试
用、
、
பைடு நூலகம்
3 不同化
量的
混凝土粗骨料，研究混凝土度，测 3
骨料体性中化的量，分骨料的始
化和性二氧化硅含量与混凝土度的系。
1试验原材料与试验方法
1.1原材料
、
三种骨料分别用5〜1、
10-16 mm的单级配骨料，按照1：2的比例混，骨料的碱
性用快速-酸检验方法测，均不存有害的
碱硅酸盐。骨料性能见表2。
细骨料:易县水洗河，泥量2.4%,细度模数2.6。
外加剂:减水剂,江苏苏博特聚M酸减水剂，固含量

铝表面钛钝化的原理

铝表面钛钝化的原理英文回答：Anodic Oxidation of Aluminum.Anodic oxidation is an electrochemical process that converts the metal surface into a decorative, durable, corrosion-resistant, anodic oxide finish. The process is widely used to protect and enhance the surface of aluminum and its alloys.The process of anodic oxidation involves the formation of a thin oxide layer on the aluminum surface. This oxide layer is typically composed of aluminum oxide (Al2O3), which is a hard, wear-resistant material. The oxide layer is formed when the aluminum surface is exposed to an electrolyte solution and an electric current is passed through the solution. The electric current causes the aluminum to oxidize, forming the oxide layer.The thickness of the oxide layer can be controlled by the voltage and duration of the anodizing process. Thicker oxide layers provide greater protection against corrosion and wear, but they can also make the surface more brittle.Anodized aluminum can be dyed to create a variety of colors. The dye is absorbed into the pores of the oxide layer, creating a permanent color.Anodized aluminum is used in a wide variety of applications, including:Architectural cladding.Automotive trim.Aerospace components.Consumer electronics.Medical devices.Titanium Anodizing.Titanium anodizing is a similar process to aluminum anodizing, but it is used to create a decorative, corrosion-resistant, and biocompatible finish on titanium and its alloys. The process involves the formation of a thin oxide layer on the titanium surface. This oxide layer is typically composed of titanium dioxide (TiO2), which is a hard, wear-resistant material. The oxide layer is formed when the titanium surface is exposed to an electrolyte solution and an electric current is passed through the solution. The electric current causes the titanium to oxidize, forming the oxide layer.The thickness of the oxide layer can be controlled by the voltage and duration of the anodizing process. Thicker oxide layers provide greater protection against corrosion and wear, but they can also make the surface more brittle.Titanium anodizing can be used to create a variety of colors, including gold, blue, purple, and green. The color of the oxide layer is determined by the thickness of thelayer and the wavelength of light that is reflected from the surface.Titanium anodizing is used in a wide variety of applications, including:Medical implants.Aerospace components.Jewelry.Watches.Eyewear.中文回答：铝表面的钛钝化原理。

高三英语化学实验与化学反应原理单选题60题

高三英语化学实验与化学反应原理单选题60题1.In the chemistry lab, we need an instrument to measure the volume of liquid. Which one is it?A.test tubeB.flaskC.beakerD.graduated cylinder答案：D。

graduated cylinder 是量筒，用于测量液体体积。

test tube 是试管，主要用于少量试剂的反应。

flask 是烧瓶，用于加热液体等。

beaker 是烧杯，可用于溶解、加热等，但不能准确测量体积。

2.When heating a small amount of liquid, we usually use which instrument?A.crucibleB.petri dishC.test tubeD.burette答案：C。

test tube 试管用于加热少量液体。

crucible 是坩埚，用于高温加热固体。

petri dish 是培养皿。

burette 是滴定管，用于滴定实验。

3.For holding and transferring solid chemicals, which instrument is suitable?A.spatulaC.funnelD.stirring rod答案：A。

spatula 是药匙，用于取固体药品。

pipette 是移液管，用于准确量取液体。

funnel 是漏斗，用于过滤等。

stirring rod 是搅拌棒，用于搅拌液体。

4.Which instrument is used to hold chemicals during filtration?A.filter paperB.funnelC.beakerD.flask答案：B。

funnel 漏斗在过滤时用于支撑滤纸并导流。

filter paper 是滤纸，不是仪器。

化学外加剂对砂浆流变性能的影响

收稿日期：2019–09–22。修订日期：2019–11–27。基金项目：科技部重点研发计划(2017YFB0310002)：长寿命混凝土制
品关键材料及制备技术；国家自然科学基金面试项目 (51778333)。第一作者：张朝阳(1994—)，男，博士。通信作者：孔祥明(1974—)，男，副教授。
ZHANG Chaoyang, YU Jianwei, KONG Xiangming, CAI Yi (Institute of Building Materials, Department of Civil Engineering, Tsinghua University, Beijing 100084, China)
吸附官能团均为羧基，分子结构和基本性质分别如图 1 和表 1 所示。图 1a 中 LPCE 为没有侧链的线性分子。图 1b 中 PCE2400 为侧链分子量为 2400 的梳型分子。图 1c 中 PCE4000 为侧链分子量为 4000 的梳型分子。此外，本研究中使用的超吸水树脂(SAP)粉末是丙烯酸与丙烯酰胺共聚的交联高分子，粒径为 180~420 μm。黏度调节剂 VMA 是
Keywords: mortar; rheological property; water-to-binder ratio; polycarboxylate superplasticizers; viscosity modifying agent
对混凝土工作性能的调控是保证施工和后期性能的关键一环[1]。混凝土的工作性包括拌和、成型过程中的流动性、均匀性和稳定性[2]。混凝土可以看成一种由基质为砂浆，悬浮颗粒为大小不同、形状各异的粗骨料组成的悬浮体系，其流变性能主要由砂浆的性能来决定。因此，对于砂浆流变性能的

勃母石溶胶结合氧化铝-莫来石多孔陶瓷的制备

勃母石溶胶结合氧化铝－莫来石多孔陶瓷的制备孙煦东　李婕内蒙古建筑职业技术学院　内蒙古呼和浩特０１００７０摘　要：以α Ａｌ２Ｏ３微粉和ＳｉＯ２微粉为原料，勃母石（γ ＡｌＯＯＨ）溶胶为结合剂，十二烷基硫酸钠（ＳＤＳ）为发泡剂，采用发泡法制备氧化铝－莫来石多孔陶瓷。

研究了勃姆石溶胶掺量（ｗ）为１％、２％、４％、５％、６％、８％，发泡剂（ＳＤＳ）掺量（ｗ）为１％、１．５％、２％、２．５％、３％、５％时对多孔陶瓷试样显气孔率和耐压强度的影响，以及烧制温度（１３００、１３５０、１４００、１４５０、１５００、１６００℃）对其性能和显微结构的影响。

研究表明：多孔陶瓷试样的显气孔率随着勃母石溶胶掺量的增加逐渐减小，耐压强度却逐渐增大；显气孔率随着发泡剂（ＳＤＳ）掺量的增加先增加后减小，而其耐压强度先减小后增加。

耐压强度随着烧制温度升高先增大后减小，而显气孔率却一直下降。

勃姆石（γＡｌＯＯＨ）掺量为５％（ｗ）、发泡剂（ＳＤＳ）掺量为２．５％（ｗ）、烧制温度１４５０℃为最优制备条件，此时，试样的耐压强度为６．７ＭＰａ、显气孔率为７９．５％、热导率为０．０８７Ｗ·（ｍ·Ｋ）－１。

关键词：勃姆石（γＡｌＯＯＨ）；发泡剂（ＳＤＳ）；氧化铝－莫来石；发泡陶瓷中图分类号：ＴＱ１７４．７６文献标识码：Ａ文章编号：１００１－１９３５（２０２１）０２－０１４０－０４ＤＯＩ：１０．３９６９／ｊ．ｉｓｓｎ．１００１－１９３５．２０２１．０２．０１１莫来石多孔陶瓷具有抗热震性好，高温蠕变小，低热导率和低热膨胀率，抗化学腐蚀性好等特点［１］，广泛应用于保温隔热、耐火材料、环境生物、化学催化剂载体等领域［２－４］。

李和祯等［５］通过Ｌａ２Ｏ３的掺杂生成了Ｌａ１．６６Ａｌ２３．０８Ｏ３７．０４相，有助于提高莫来石陶瓷的强度。

杨孟孟等［６］通过添加淀粉和ＡｌＦ３原位生成莫来石晶须，制备了自锁结构的多孔陶瓷。

石宇恒等［７］以聚苯乙烯泡沫球为造孔剂，采用振动浇注成型，当聚苯乙烯泡沫球加入量为浆料总体积的５０％时，１４００℃的高温抗折强度高达２．６４ＭＰａ。

三氧化二铝含量对铁_氧化铝复合材料复介电常数的影响_曾国勋

三氧化二铝含量对铁/氧化铝复合材料复介电常数的影响Effect of A l2O3Concentration upon Com plexPermittivity of Fe/A l2O3Composites曾国勋,张海燕,胡礼初,陈易明(广东工业大学材料与能源学院,广州510006)ZENG Guo-x un,ZHANG H ai-y an,H U Li-chu,CH EN Yi-ming(Faculty of M ate rial&Ene rg y,Guangdo ngUniver sity of Technology,Guang zhou510006,China)摘要:采用柠檬酸硝酸盐法制备含不同氧化铝含量的铁氧体,并用氢还原该铁氧体得到含不同氧化铝量的超细与纳米粉混合的铁粉。

粉末颗粒外形呈针状和片状。

铁/氧化铝复合材料的复介电常数实部随氧化铝含量增加,而逐渐下降。

介电常数损耗随氧化铝含量增加,而逐渐下降,且损耗峰逐渐向高频移动。

通过加入铁中的氧化铝含量可以调节铁的复介电常数。

关键词:A l2O3;Fe;复合材料;复介电常数中图分类号:TB34 文献标识码:A 文章编号:1001-4381(2007)03-0007-03A bstract:The sheets of ferrite composites w ith different co ncentratio n of Al2O3w ere synthesized by citric nitrate so l gel method.The mix ture po w ders have the fine and nano Fe/Al2O3composites w ere obtained,in w hich the ferrite w as reduced by hy drog en.I t is found that Fe/Al2O3composites have a shape o f needle and flake by SEM examinatio n.The real and imaginary parts of the com plex permit-tivity o f Fe/Al2O3composites decreased,and dielectric lo ss(ε″)peak shifted to hig her frequency w ith the increase o f Al2O3concentration in Fe/Al2O3composites.Relative permittivity of Fe po w ders is adjusted by adding different A l2O3concentration.Key words:A l2O3;Fe;com po sites;com plex permittivity 近些年,由于民用电磁产品运用的日益普及,电磁干扰问题日益严重。

多孔碳电极用于多硫化钠溴储能电池

多孔碳电极用于多硫化钠!滨储能电池周汉涛1,29张华民19葛善海19刘浩19衣宝廉1(1.中国科学院大连化学物理研究所燃料电池工程中心9辽宁大连11602392.中国科学院研究生院9北京100039)摘要研究了多硫化钠-溴 PSB 储能电池用多孔碳电极0电极材料为活性炭\导电炭黑\热塑性聚合物粘结剂9电极采用热压成型方法制备0用多孔炭电极作为电池正负极9系统地探讨了电极组成\活性炭颗粒粒径\造孔剂对电池充放电性能的影响0粘结剂量一定时9导电炭黑\活性炭比例存在最优值0大颗粒活性炭有利于保持电极的机械稳定性0加大造孔剂的量9促进了电极内孔的连通性9电池性能提高0活性炭制得的电极具有较高的电化学活性9在80 C \120mA/cm 2放电电流密度时比功率达0.14 W/cm 2 1.19 V 9可见活性炭是一种高性价比的PSB 储能电池电极材料0关键词活性炭9造孔剂9储能电池9多硫化钠9溴中图分类号：TM 911.18 文献标识码：A 文章编号：1002-087 X (2005)03-0170-05Porous carbon electrodes for sodium polysulfide-bromine redox flowenergy storage cellZHOU Han-tao 1,2, ZHANG Hua-min 1, GE Shan-hai 1, LIU Hao 1, YI Bao-lian 1(1.fuel cell R&D Center a Dalian Institute of Chemical Physics a Chinese Academy of Sciences a Dalian Liaoning 116023a China g2.Graduate School of the Chinese Academy of Sciences,Beijing 100039,China)Porous carbon electrodes for sodium polysulfide/bromine (PSB) energy storage cell were investigated in this paper.The electrodes were prepared by hot isostatic pressing with activated carbon (AC), electrical conductive black carbon (BC)and thermoplastic binder. Effects of composition of electrode, particle size of activated carbon and weight proportion of poreprecursor on the charge/discharge performance of the cell were examined. Optimization was needed for the ratio of BC/ACunder the same amount of binder. It preferred to using activated carbon has large particle size for the mechanical stability ofthe electrode. Higher performance was obtained when more pore precursor was utilized. The power density output of up to0.14 W/cm 2 (1.19 V) was obtained when the porous carbon electrodes were applied. It was concluded that the activated carbon was an excellent electrode material with high performance/price ratio.: activated carbong pore precursorg energy storage cellg sodium polysulfideg bromine收稿日期 2004-06-05""""""基金项目中国科学院领域前沿项目基金资助(DICP-K 2002 D 3 )""""""作者简介周汉涛(1976 )a 男a 湖北省人a 博士研究生a 主要研究方向为燃料电池与化学工程0: ZHOU Han-tao(1976 )a male a candidate for Ph D.联系人张华民电与普通商品不同a 难以储存a 所以电站的建造容量须满足最大电力需求0一些可再生能源如风能\光能需储能系统配合0一个有效的解决方法是建造储能系统a 在用电低谷时将富余的电能储存起来a 在用电高峰时提供电能a 降低电站最大容量a 保证电力平稳输出0电能的储存在预防电力供应灾难事件\军事应用等方面也具有重大意义0电能储存技术有许多a 其中化学电源储能技术由于不受地理位置与时间的限制a 具有很强的实用性0美国人Remick [1]发明了PSB 储能电池a 英国Innogy 公司致力于开发这一基于燃料电池技术的新型储能系统a 并建造了第一座商业化储能电厂[2]a 电容量达120 MWh a 最大输出功率15 MW a 已在2002年建成并投入使用a 这是目前世界上唯一商业化且规模最大的新型化学储能电厂0PSB 储能电池属液流电池a 功率和储存容量可以分开设计a 可以提供5~500 MW 的功率a 在常温常压下运行a 并且具有能量转化率高\启动速度块\充放电性能好\充放电切换迅速\使用寿命长\制造成本低\环境友好等特点a 和其它机械\热力\电磁储能技术相比有很强竞争力a 特别适用于MW 级大规模储能电站[2]a 可用于大功率可移动电源a 是电动汽车和不依赖空气推进潜艇的理想候选储能电池之一[3]a 可以与其它可再生能源联合使用[4,5]a 随着进一步的成本降低和性能提高a 相信在其它方面的应用也会越来越广0电极是电池关键部件a 要有一定的机械强度\良好的导电性\比较大的孔隙率a 在电解液中有良好的化学与电化学稳定性a 电极材料成本也是影响电池商业化的重要因素a 因此有必要研制廉价而又容易获得的电极材料0葛善海等用聚丙烯腈炭毡作为PSB 储能电池的正负极材料[6,7]9Zito 用活性炭颗粒作为溴电极材料[8]9文献[9]采用活性炭布作为溴电极9Zito 的空气-多硫化物电池[10]阳极电解质为多硫化物a 电极材料为Barnebey-Cheney 公司生产的活性炭9Zito 的铁-硫电池[11]所!1 电极特征参数 Tab.1 Characteristic parameters Of electrOdes!"#$Electrode No. !"#$Electrode materials 质量百分比MBSS pCICCI BgC % !"Thickness / 11 !"#Bulk resistivity /~cm1 BC / AC / PVDF 0.0 / 73.3 / 26.7 4.13 9.362 BC / AC / PVDF 3.3 / 70.0 / 26.7 4.20 0.733 BC / AC / PVDF 13.3 / 60.0 / 26.7 3.36 0.424 BC / AC / PVDF 23.3 / 50.0 / 26.7 3.74 0.305 BC / AC / PVDF 15.0 / 70.0 / 15.0 4.90 0.256 BC / AC / PVDF / NaBr 13.5 / 63.0 / 13.5 / 10.0 4.10 0.237 BC / AC / PVDF / NaBr 12.0 / 56.0 / 12.0 / 20.0 4.00 0.278 BC / AC / PVDF / NaCl 15.0 / 70.0 / 15.0 / 20.0 5.08 0.289 BC / AC / PVDF / NaCl 15.0 / 70.0 / 15.0 / 30.0 5.20 0.3910 BC / AC / PVDF 15.0 / 70.0 / 15.0 4.45 0.3611 BC / AC / PVDF 15.0 / 70.0 / 15.0 4.37 0.41! !"1011活性炭颗粒粒径分别为 120!120160!Notez The particle size of the electrode No. 10 and 11are 80-120,120-160 mesh respectively.用的硫氧化还原电极材料也是活性炭!本文介绍了PSB 储能电池正"负电极均使用活性炭电极的研究结果!1 实验部分1.1 膜的预处理采用钠型Nafion-117膜作为阳离子交换膜#膜在使用前需要进行预处理将氢型膜转化为钠型膜#并除去膜中有机的和无机的杂质[12]!先将膜放入5%的H 2O 2于353 K 的水浴中加热约1 h 以除去有机杂质#然后将膜用去离子水洗涤$将膜放在0.5 mol/L H 2SO 4溶液中于353 K 的水浴中加热约1 h 以除去无机杂质#将膜用去离子水洗涤$再将膜放在1.0 mol/L NaOH 溶液中于353 K 的水浴中加热约2 h #将膜转化为钠型#然后用去离子水洗涤!1.2 电极的制备将导电材料(BC #美国Cabot Corp. XC-72炭黑#以下同)"活性炭颗粒(AC #山西新华化工厂#比表面积830 m 2/g #以下同)"聚偏氟乙烯(PVDF #上海三爱富新材料有限公司#以下同)粉末以及造孔剂按一定质量比混合#置于模具中热压成型(电极参数见表1)#热压温度200 #电极的实际成型压力控制在2 MPa,热压时间30 min !电极自然冷却后#用20%乙醇水溶液浸渍电极#然后用1.0 mol/L 80 C NaOH 水溶液浸渍#最后用80 C 去离子水洗涤#直到造孔剂被去除!如不特别说明#活性炭颗粒直径40 80目#电极工作面积为5 cm 2!1.3 电池结构与工艺流程PSB 储能电池的组装如图1所示#阳离子交换膜的两侧为电极#两块极板为石墨板#石墨板上的沟槽为电解质流动通道#垫片为聚四氟乙烯垫片#两块端板为不锈钢板#端板上镶嵌聚四氟乙烯接头!PSB 储能电池流程如图2#正"负极的电解液经泵流入电池#在电极上发生电化学反应后流入各自的储罐中#中间用阳离子交换膜隔开#电池外接负载或者电源#电池及循环的电解液温度由温度自动控制器控制!阴极"阳极电解液储罐充氮气以防止氧气的干扰!实验项目如果不是特别标明#操作条件如下%电池评价温度为80 C #先充电再放电#充放电电流密度为100 mA/cm 2#阴极"阳极电解液体积为50 mL #循环量均保持为30 mL/min #充电初始阳极电解液为1.0 mol/L Na 2S 4#阴极电解液为4.0 mol/L NaBr #到50%充电状态后放电#即放电初始负极电解质为2.0 mol/L Na2S 2#正极电解液为2.0 mol/L NaBr+1.0 mol/L Br2!2 实验结果与讨论2.1 工作原理输送到PSB 储能电池的电解液发生电化学反应后流出电池#电极并不参与化学反应#在放电时负极电极反应为%(x +1)Na 2S x !2 Na ++x Na 2S x +1+2 e -x =1~4 (1) Na +通过阳离子交换膜到达正极#与溴发生电极反应%1151413121110987654321, 15. 端板End plate $2, 4, 7, 9, 12, 14. 衬垫Gasket $3.阳极板Anode plate $5, 11. 支撑架Frame $6. 阳极Anode $8. 阳离子交换膜Cation exchange membrane $10.阴极Cathode $13. 阴极板Cathode plate 图1 多硫化钠/溴储能电池结构图Fig.1 Structure of sodium polysulfide/bromine energy storage cell 负载或电源Load or power supply!"Negative !"Positive s图2 多硫化钠-溴储能电池流程示意图Fig.2 Schematic diagram of sodium polysulfide /bromine energystorage batteryBr 2+2 Na ++2 e -～2 NaBr (2) 放电时电池反应为1(X +l)Na 2S X +Br 2～X Na 2S X +l +2 NaBr (3) 充电时电极反应逆向进行O 常温常压下a 正极电位l.06~l.09 V a 负极电位!0.48~!0.52 V a 单电池开路电压为l.54~l.6l V O !"!#电极组成的影响四种不同组成的电极组装的电池性能如图3所示O 固定粘结剂使用量为26.7%a 当炭黑与活性炭比值为l3.3Z60.0时电池性能最好O 实验结果表明在粘结剂量一定时a 高导电材料和活性炭的比例存在最优值O 因为不加炭黑时由于活性炭本身导电性不好再加上绝缘的聚合物a 制得的电极电阻很大a 加入高导电炭黑后电阻下降很多a 有利于电池性能提高a 而活性炭用量减少导致电极反应面积降低a 从而降低电池性能O 粘结剂只起粘结作用a 电阻很大a 所以其用量需要优化以兼顾导电性能和机械强度的要求a 这是因为PSB 储能电池的电解液是循环流动的a 这要求电极具有较好的机械性能a 能承受电解液的冲刷a 如果用量过低其机械性能不稳定a 在组装电池和运行时发生电极破碎\炭颗粒脱落等现象O !"$##活性炭粒径的影响由活性炭组成的电极具有两种孔隙1颗粒之间形成的粗孔a 颗粒内部的细孔O 粗孔孔径较大彼此连通a 是反应物和离子电荷传输的主要通道a 其孔壁构成电极过程的主要反应表面[l3]O 所以活性炭颗粒越小a 形成的大孔越多a 有利于电极反应O 但从图4可看出a 存在一个最优颗粒粒径O 我们认为这是因为活性炭颗粒变小a 同样大小的电极所用活性炭颗粒数将增加a 而导电材料和粘结剂的颗粒数量不变a 造成炭颗粒之间的导电性和粘结性降低a 导致电极电阻上升见表l 以及机械性能的下降O 实验过程中发现a 大颗粒压成的电极机械性能好a 不易破碎a 小颗粒压成的电极易破碎a 随着充放电的进行伴随炭颗粒的脱落a 颗粒越小损失越多a 小于l60目时充放电已不能进行O 从图5可看出a 随着炭颗粒粒径的减小a 在充电过程中电压上升幅度加大a 而放电过程的电压下降速度加快a 有效放电时间减少O 另外颗粒过细压成的电极过于紧密a 颗粒之间形成的孔连通性较差a 不利于电极反应的进行O 所以不宜用粒径小于l60目的活性炭来制备电极O!"%#造孔剂的影响加入造孔剂增加了电极内的粗孔a 有利于电池性能提高O 分别用NaBr \NaCl 作为造孔剂制备电极O 用NaBr 时a 四种材料的总质量保持恒定a 用NaCl 时其它三种材料质量保持恒定O 图6~图9显示随着造孔剂量的增加a 电池性能提高a 当造孔剂量到20%以上时电池性能已到最高点a 继续加大用量没有必要a 因为电极内大孔增多其机械强度必定下降O 从图8可看出a 充电电流密度达到l20 mA/cm 2 电压为l.98 V a020100 40140120 2.82.42.01.61.2 V /VJ /(mA cm )-2曰___充电Charge 9回___放电Discharge 9BC / AC / PVDF=0.0 / 73.3 / 26.7么___充电Charge 9’___放电Discharge 9BC / AC / PVDF=3.3 / 70.0 / 26.7▽___充电Charge 9▼___放电Discharge 9BC / AC / PVDF=l3.3 / 60.0 / 26.7O ___充电Charge 9．___放电Discharge 9BC / AC / PVDF=23.3 / 50.0 / 26.7图3 电极组成不同时电池电压-电流密度曲线Fig.3 Cell Voltage Vs . current density plots for cell with Various electrode compositions 么___充电Charge 9’___放电Discharge a 40~80 目Mesh▽___充电Charge 9▼___放电Discharge, 80~l20目MeshO ___充电Charge 9．放电___Discharge, l20~l60目Mesh图4 活性炭粒径不同时电池电压-电流密度曲线Fig.4 Cell Voltage Vs . current density plots for cell with Variousparticle size of actiVated carbon020100 401401202.42.01.61.2V /VJ /(mA cm )-22.21.81.41.040~80目Mesh 80~l20目Mesh........l20~l60目Mesh 图5 活性炭粒径不同时电池充放电电压-时间曲线Fig.5 Cell Voltage Vs . time plots for cell during charge/dischargewith Various particle size of actiVated carbon0210864t /h 2.42.01.61.2V /V0.0BC / AC / PVDF / NaBr = 15.0 / 70.0 / 15.0 / 0.09BC / AC / PVDF / NaBr = 13.5 / 63.0 / 13.5 / 10.09........BC / AC / PVDF / NaBr = 12.0 / 56.0 / 12.0 / 20.0图7 NaBr 含量不同时电池充放电电压-时间曲线Fig.7 Cell Voltage Vs . time plots for cell during charge/discharge with Various content of NaBr 同样电流密度输出电压为1.19 V 9即比功率达到0.14 W/cm 20从表1可看出造孔剂的使用增加了电极电阻9但这种影响较小0总的说来造孔剂增加了连通性好的孔9从而提高了电池性能0!"结论(1)活性炭制得的多孔电极具有较高的电化学活性9在80 C 下充电电流密度达到120 mA/cm 2(电压为1.98 V )9放电电流密度为120 mA/cm 2时输出电压为1.19 V 9即功率密度达到0.14 W/cm 20可见活性炭是一种高性价比的PSB 储能电池电极材料0(2)粘结剂量一定时9导电材料\活性炭比例存在最优值9粘结剂的量需兼顾导电性能和机械强度0粘结剂用量为26.7%时9炭黑与活性炭比值为13.3Z60.0的电池性能最好0(3)小颗粒活性炭制备的电极易破碎9在电池运行过程中出现炭颗粒脱落现象9所以活性炭颗粒粒径应不小于160目0(4)造孔剂的使用增加了电极的有效反应面积9改善了传质9从而提高了电池性能9当用量达20%后电池性能已达到最高点9继续加大用量作用不大反而会降低电极机械强度0参考文献：[1] REMICK R J, ANG P G P. Electrically rechargeable anionicallyactiVe reduction-oxidation electrical storage-supply system [P].US 4485154, 1984.[2] PRICE A, BARTLEY S, Male S, et al . A noVel approach to utilityscale energy storage [J].Power Eng J,1999,13(3):122 129.[3] LAKEMAN J B, BAMES P, CARNSTONE W, et al . The Rege- nesys fuel cell for air independent power [J]. Warship 99,1999,6:1 14.么充电Charge 9A 放电Discharge 9BC / AC / PVDF / NaBr = 15.0 / 70.0 / 15.0 / 0.0① 充电Charge 9＠放电Discharge 9BC / AC / PVDF / NaBr = 13.5 / 63.0 / 13.5 / 10.0▽ 充电Charge 9▼ 放电Discharge 9BC / AC / PVDF / NaBr = 12.0 / 56.0 / 12.0 / 20.0图6 NaBr 含量不同时电池电压-电流密度曲线Fig.6 Cell Voltage Vs . current density plots for cell with Various content of NaBr020100 401401202.42.01.61.2 V /VJ /(mA cm )-22.21.81.41.00210864t /h2.42.01.61.2 V /V 0.0 么充电Charge 9A 放电Discharge 9BC / AC / PVDF / NaCl=15.0 / 70.0 / 15.0 / 0.0① 充电Charge 9＠放电Discharge 9BC / AC / PVDF / NaCl = 15.0 / 70.0 / 15.0 / 20.0▽ 充电Charge 9▼ 放电Discharge 9BC / AC / PVDF / NaCl = 15.0 / 70.0 / 15.0 / 30.0图8NaCl 含量不同时电池电压-电流密度曲线Fig.8 Cell Voltage Vs . current density plots for cell with Variouscontent of NaCl020100 401401202.42.01.61.2V /VJ /(mA cm )-22.21.81.41.00210864t /h 2.42.01.61.2V /V0.0BC / AC / PVDF / NaCl = 15.0 / 70.0 / 15.0 / 0.09BC / AC / PVDF / NaCl = 15.0 / 70.0 / 15.0 / 20.09.......BC / AC / PVDF / NaCl = 15.0 / 70.0 / 15.0 / 30.0图9 NaCl 含量不同时电池充放电电压-时间曲线Fig.9 Cell Voltage Vs . time plots for cell during charge/dischargewith Various content of NaCl[4] PRICE A.The Regenesys energy storage system [A]. Renewable Energy Storage [C]. ImechE Semin: Professional Engineering Pub- lishing Ltd, 2000.11 24.[5] PRICE A, MCCARTHY L. Power generation using renewables and the Regenesys energy storage system [A]. Power Generation by Renewables [C]. ImechE Semin: Professional Engineering Publish- ing Ltd, 2000.195 206.[6] 葛善海, 衣宝廉, 付宇,等. 多硫化钠-溴新型再生燃料电池的研究[J]. 电源技术, 2002, 26(5):355 358.[7] 葛善海, 衣宝廉, 顾红星,等. 高效率多硫化钠/溴储能电池的研究[J]. 电池, 2003,33(1):12 14.[8] ZITO R. Zinc-bromine battery with long-term stability [P].UK GB 2132004, 1984.[9] MIYAGAWA H. Positive electrode of zinc-bromine battery [P]. JP 10064557, 1998.[10] ZITO R. Electrochemical apparatus for power delivery utilizationan air electrode [P]. WO 9409524, 1994.[11] ZITO R. Electrochemical energy storage and power delivery pro- cess utilizing iron-sulfur couple [P]. WO 9409525, 1994.[12] MURPHY O J, HITCHENS G D, MANKO D J. High power den-sity proton-exchange membrane fuel cells [J]. J Power Sources,1993, 47(3): 353 368.[13] 查全性. 电极过程动力学导论[M].第三版北京科学出版社,2002.346.图8 102 A 放电端电压及正负极镉电压曲线Fig.8 Voltage curves of battery and Cd electrode at 102 A 从图7~图8中可以发现蓄电池C 10 和C 1容量是由正极容量控制这与电池解剖结果基本一致即蓄电池正极活性物质存在一定程度的软化与脱落 2.5 提高蓄电池循环特性的措施与建议2.5.1 提高蓄电池的充电接受能力显然充电接受能力对蓄电池的循环特性起着非常重要的作用假若每个循环中存在很小的容量亏损其累积起来的后果是极其严重的蓄电池制造工艺应重点关注充电性能与充电性能密切相关的是充电电压的选择充电电压高充电相对充分但同时会带来正极板栅腐蚀~活性物质软化脱落及电池失水的加速等问题使蓄电池的寿命缩短我们认为在循环使用中,每个单体电池的充电电压不高于2.40 V 是恰当的 2.5.2 提高蓄电池的动态均匀一致性蓄电池均匀一致性的概念不能仅局限于初始容量~负荷电压及浮充电压应该是广义的应涉及所有的零部件~原材料及制造过程同时均匀一致性必须是动态的贯穿于整个寿命周期其中有两个关键项一是蓄电池的气密性和阀的开闭压力提高蓄电池槽~盖及封接的质量确保电池在整个寿命期间气密性指标的合格安全阀具备合适的开闭压力以及在整个寿命期间的稳定性这些都有利于控制水的损耗提高各单体之间水损耗的一致性二是保持极板的法向压力及其均匀一致性通过紧装配技术在正极板法向保持40 kPa 的法向压力有助于抑制正极活性物质膨胀减少软化脱落延长使用寿命[8] 其难点是如何保证在使用过程中压力不下降这有待于进一步研究总而言之在现有技术水平的前提下提高蓄电池的均匀一致性是延长使用寿命的最有效途径之一 3 结论<1>试验温度对阀控免维护铅酸蓄电池循环放电深度有较大的影响<2>在1 h 放电循环过程中阀控免维护铅酸蓄电池C 10和C 1容量同步下降<3>蓄电池单体不均衡率变差是循环用蓄电池提前失效的原因之一<4>在循环模式下的蓄电池最终失效原因是正极活性物质的软化~脱落<5>改善充电接受能力提高各单体的均匀一致性有助于提高阀控免维护铅酸蓄电池的循环特性延长循环寿命参考文献：[1] 吴贤章.循环用阀控电池失效模式的研究[J].蓄电池 2002 <4> 151 154.[2] 毕道治.电动车电池的开发现状及转弯展望[J].国际电源商情 2002 (8) 19 25.[3] TB/T 3061-2002 铁路机车车辆用阀控密封铅酸蓄电池[S].[4] 朱松然.蓄电池手册[M].天津天津大学出版社 1998.59.[5] PAVLOV D.阀控式密封铅酸蓄电池国际讲学班讲义[M].中国杭州 2000.4.[6] 王震坡.电动汽车动力蓄电池组不一致性统计分析[J].电源技术 2003 <5> 438 441.[7] 高建峰.OTSLA 蓄电池均匀性的研究[J].电池工业 1999 (4)141.[8] FUCHIDA K. Towards improved manufacture of lead/acid batter ies panel discussion [J].J Power Sources, 1992,38:197 227.1.02.0V /V 0200.0 1.52.5!" Cd !"# Cell !" Cd 100 40t lmin (上接第166页)"!"!!!!!!!!!!!"!"。

氧化铝陶瓷分析解析

密度为3.5g/cm3，仅为钢铁的一半，可大大减轻设备负荷。
耐磨陶瓷主要技术指标
项目
指标
氧化铝陶瓷含量 ≥92%
密度
≥3.6 g/cm3
洛氏硬度
≥80 HRA
抗压强度
≥850 Mpa
断裂韧性
≥4.8MPa·m1/2
抗弯强度
≥290MPa
导热系数
20W/m.K
热膨胀系数
7.2×10-6m/m.K
Sintering of nanopowders
Initially the dried powders were presintered at 600 ℃ to remove the organic and other residues present in the material and then ground into fine mixing by both sintering techniques.Further the presintered powder was mixed with 2wt% of PVA binder and then cylindrical pellets were uniaxially compacted at a pressure of 4 tones for 3 min.
目前改善氧化铝陶瓷的断裂韧性有以下几种途径:
(1)颗粒弥散增韧; (2)纤维和晶须增韧; (3)氧化锆相变增韧; (4)复合增韧; (5)自增韧等。
颗粒弥散增韧
颗粒弥散增韧机理主要有热应力诱导微裂纹增韧、切应力阻碍微裂纹扩展(钉扎微裂纹)增韧、微裂纹偏转与分支、弱化应力集中增韧及细化基体晶粒。颗粒弥散增韧与温度无关,可以作为高温增韧机制。对颗粒增韧氧化铝陶瓷的研究中, 主要以高熔点、高强度、高弹性模量的碳化物、氮化物、硼化物第二相粒子和具有延展性的金属颗粒为增韧相