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1.
以吐温-80(Tw-80)即C6-4H124O26-80作分散剂,用超声波沉淀法制备出针形和准球形混合的纳米β-Ni(OH)2,将制备的纳米粉体以8%(质量分数,下同)比例掺入到微米级球镍中制成复合镍正极,LaNi5合金制成电池负极,研究了不同Tw-80比对纳米粉体振实密度及其复合镍正极放电性能的影响.结果表明:振实密度和放电容量均随Tw-80用量增加先增大后减小;复合镍电极的放电平台比纯球镍电极高;Tw-80用量为2%制备的纳米粉体,以8%比例与球镍混合时,其复合镍电极的放电容量最大,达到256.7 mAh/g,比纯球镍电极的放电容量(230.7 mAh/g)高出11.3%,寿命也比后者有一定延长.  相似文献   

2.
采用溶胶凝胶法制备层状LiMnO2,并掺杂不同比例的稀土元素进行改性.XRD分析结果表明,掺杂镧元素的层状锰酸锂呈斜方晶系,纯度较高.SEM照片显示这种产物为层状结构,且粒度大小分布较为均匀.用循环充放电测试考察了产物的电化学性能,结果显示掺杂6%La的层状锰酸锂正极材料的初次放电比容量为128 mAh/g,但循环稳定性较差;而掺杂了4%La的层状锰酸锂则表现了良好的循环稳定性,首次放电比容量达到了102 mAh/g,多次充放电之后容量基本没有衰减,仍然能保持较高的比容量.从交流阻抗数据分析,掺镧量为4%的样品扩散阻抗较小,充放电可逆性较好.  相似文献   

3.
采用超声波辅助沉淀法制备Cu单掺杂和Cu/Al复合掺杂的纳米Ni(OH)2样品,测试样品的晶相结构、粒径、形貌、振实密度及电化学性能。结果表明,样品均具有α相结构且其平均粒度的分布范围窄,Cu单掺杂的纳米Ni(OH)2呈现不规则形态,而Cu/Al复合掺杂的纳米Ni(OH)2呈准球状且具有更大的振实密度。将纳米样品以8%的比例掺入到商业用微米级球形镍中制成混合电极。充放电和循环伏安测试结果表明,Cu/Al复合掺杂纳米Ni(OH)2的电化学性能优于Cu单掺杂的纳米Ni(OH)2的,前者的放电比容量最高达到330mA·h/g(0.2C),比Cu单掺杂样品的高12mA·h/g,比纯球镍电极的高91mA·h/g。此外,Cu/Al复合掺杂纳米样品的质子扩散系数比Cu单掺杂样品的高52.3%。  相似文献   

4.
采用化学还原法得到纳米级Sn-Co粉末,再经过与硬碳粉混合球磨得到Sn-Co-C复合粉体.能谱测试表明,样品Sn、Co、C原子分数分别为3.89%、1.47%、94.64%.SEM观察显示,50~100 nm锡钴微粒附着在片状的硬碳颗粒上.复合粉体与锂片组成模拟电池,首次放电比容量为558.4 mAh/g,首次充电比容量为338.5 mAh/g.30次循环后,放电比容量保持在348.2 mAh/g,保持率为62.4%;充电比容量保持在335.4 mAh/g,保持率为99.1%.充放电比容量较硬碳提高3倍左右.由分析放电曲线可知,第一次放电后在电极表面形成了固体电解质界面膜(SEI)膜,循环一次后该膜消失.  相似文献   

5.
分别采用共沉淀法和超声波共沉淀法制备Al/Co复合掺杂α-Ni(OH)2样品A和B,用XRD和激光粒度仪表征样品的晶相结构和粒度分布。结果表明,样品B比样品A具有较多的晶格缺陷和较小的平均粒径。循环伏安特性及电化学阻抗谱测试显示,样品B比样品A具有更好的电化学性能:较好的反应可逆性、较低的电荷转移电阻和较高的循环寿命等。样品B的质子扩散系数为1.96×10-10cm2/s,约为样品A(9.78×10-11cm2/s)的2倍。充放电测试显示,样品B的放电比容量达到308mA·h/g,比样品A的放电比容量高25mA·h/g。  相似文献   

6.
分别采用共沉淀法和超声波共沉淀法制备Al/Co复合掺杂α-Ni(OH)2样品A和B,用XRD和激光粒度仪表征样品的晶相结构和粒度分布。结果表明,样品B比样品A具有较多的晶格缺陷和较小的平均粒径。循环伏安特性及电化学阻抗谱测试显示,样品B比样品A具有更好的电化学性能:较好的反应可逆性、较低的电荷转移电阻和较高的循环寿命等。样品B的质子扩散系数为1.96×10-10cm2/s,约为样品A(9.78×10-11cm2/s)的2倍。充放电测试显示,样品B的放电比容量达到308mA·h/g,比样品A的放电比容量高25mA·h/g。  相似文献   

7.
稀土Y掺杂非晶态纳米Ni(OH)2的结构及其电化学性能研究   总被引:2,自引:1,他引:1  
以Tween-80/n-C4H9OH/c-C6H12/NiSO4水溶液体系,采用微乳液快速冷冻沉淀法制备出稀土Y掺杂非晶态纳米级氢氧化镍粉体材料.采用XRD、SAED、SEM、TEM、EDS、Raman、IR,粒度分析和比表面等测试方法对所制备的粉体进行了结构形态表征,并对其充放电性能和交流阻抗谱进行测试.结果发现,适量稀土元素Y的掺入使非晶态纳米氢氧化镍的结构缺陷增多、无序性增强,平均粒度减小、比表面积增大,有利于降低其溶液电阻、电荷转移电阻和Warburg阻抗,从而提高其放电比容量.样品作为MH-Ni电池正极材料以0.2 C充放电,终止电压为1.0 V,当掺杂Y的质量分数为4%时,放电比容量达到333.3 mAh/g.  相似文献   

8.
在三元液相体系中合成了球形Li2MnSiO4/C 复合正极材料,XRD、SEM和电化学性能测试对材料进行了表征。XRD测试表明Li2MnSiO4 具有正交结构,对应Pmn21空间群。SEM显示所得样品为小于1 μm的球形颗粒。将Li2MnSiO4/C 组装成扣式电池进行电化学测试的结果表明,在1.5~4.6 V,该样品的初始充电容量达310 mAh/g,放电容量高至 286 mAh/g,为理论比容量的85.9%;循环30 次后放电比容量为142 mAh/g。  相似文献   

9.
在三元液相体系中合成了球形Li_2MnSiO_4/C复合正极材料,XRD、SEM和电化学性能测试对材料进行了表征。XRD测试表明Li_2MnSiO_4具有正交结构,对应Pmn21空间群。SEM显示所得样品为小于1μm的球形颗粒。将Li_2MnSiO_4/C组装成扣式电池进行电化学测试的结果表明,在1.5~4.6 V,该样品的初始充电容量达310 mAh/g,放电容量高至286 mAh/g,为理论比容量的85.9%;循环30次后放电比容量为142 mAh/g。  相似文献   

10.
采用化学共沉淀法,制备出Cl-和Zn2 阴阳离子复合掺杂α-Ni(OH)2粉体.样品材料利用XRD、EDS、SEM、IR、DSC-TG和粒度测试仪进行结构形态及物理特性表征分析.同时以其为活性物质合成镍正极材料并组装MH-Ni电池,测试其充放电、循环可逆特性和交流阻抗等电化学性能.实验结果表明,在掺杂物质摩尔比为Cl-:Zn2 =1:3时,Cl-和Zn2 复合掺杂α-Ni(OH)2为层状结构,结晶水含量较高,热分解温度低.其MH-Ni电池在以80 mA/g恒流充电5 h,40 mA/g恒流放电至终止电压为1.0 V的充放电制度下,电化学极化阻抗较小,放电比容量为354.08 mAh/g,放电平台平稳、中值电压高达1.313 V,且经过多次充放电循环后,其电极活性物质仍然保持α-Ni(OH)2状态,电极过程结构稳定,循环可逆性较好,具有较高的电化学活性.  相似文献   

11.
吴玉梅  熊晓云  靳蓉  孙敬民  杨林  罗晓星 《金属学报》2005,10(10):1100-1103
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。  相似文献   

12.
Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.  相似文献   

13.
The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.  相似文献   

14.
《中国铸造》2014,(6):537-538
The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.  相似文献   

15.
《中国铸造》2014,(6):542-546
China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society (FICMES) each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.  相似文献   

16.
正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.  相似文献   

17.
正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis  相似文献   

18.
Preface     
<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of  相似文献   

19.
The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.  相似文献   

20.
The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward.  相似文献   

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