谈电池的使用与维护

随着现代教育技术在教学中的普遍应用，我们会用到各种不同特性的电池，要用好这些电池，了解他们的特性和使用方法是很有必要的。１）现阶段我们常用的充电电池有铅酸电池、镍镉电池、镍氢电池和锂离子电池。在使用铅酸电池和镍镉电池时，如果多次充电到一定容量但未充满就停止充电，以后再充电时电池记住了以前充电的容量，就只能充到这个容量而不能充满；如果多次放电到一定容量但未放出全部容量就给电池充电，以后再放电时电池记住了以前放电的容量，电能无法全部放出。这就是电池的记忆效应。任何封装形式的铅酸电池和镍镉电池都有很强…     

一种超级电容器容量测试方法的研究

超级电容器较传统电容器而言有非常大的容量,但是其表现出显著的"非传导性吸收"储能方式,用传统的方法将不能准确地对超级电容器进行测试。依据IEC 62391标准规定的恒定电流放电测试法,利用电荷守恒定律和面积等效原理,提出了一种在无法实现恒流放电情况下测量超级电容器容量的测试方法——恒定电阻放电测试法。实验结果显示,通过此方法可测试出超级电容器的容量。     

压力对Zr41.2Ti13.8Cu12.5Ni10Be22.5块体非晶合金晶化行为的影响

介绍了用于压力测量的新型bridgman装置，并结合X射线衍射分析技术（XRD）研究了常压、高压条件下Zr41．2Ti13．8Cu12．5Ni10Be22．5块体非晶合金的晶化。结果表明，在相同的退火条件下（400℃，退火3小时），增大压力有利于Zr41．2Ti13．8Cu12．5Ni10Be22．5块体非晶合金的晶化；压力越大获得晶化相的晶粒尺寸越大。     

XFZ—dI型蓄电池容量放电指示器的研制

由于煤矿井下的特殊性,其运输设备电机车常用蓄电池电源作为驱动能源,为了随时监测电机车运行中蓄电池容量,以防止蓄电池过放电,电机车上常安装有蓄电池容量放电指示器.XFZ-dI型蓄电池容量放电指示器,主要根据蓄电池容量与端电压的关系,利用集成电路及外围电路构成检测、放大、报警等环节,以达到蓄电池容量指示的效果,电路结构简单,性价比高,是一种较适用的煤矿井下指示防爆电机车蓄电池容量的设备.     

铅酸蓄电池放电特性研究

阐述了阀控铅酸蓄电池电动势与放电强度及放电时间的关系,通过对铅酸蓄电池工作原理、负极钝化机理,以及放电电流、放电温度对放电容量等的影响等方面的说明,来分析阀控铅酸蓄电池的放电特性.     

Ag对Mg-Sm系稀土镁合金的电磁屏蔽性能影响研究

采用金相显微镜、扫描电镜、X-射线多晶衍射仪等分析了Mg-3.5Sm-0.6Zn-xAg-0.5Zr合金的显微组织结构,通过RD-S02屏蔽效能测试仪测定Ag含量的变化对Mg-3.5Sm-0.6Zn-xAg-0.5Zr电磁屏蔽性能的影响规律.结果表明：随着Ag含量的增加,Mg-3.5Sm-0.6Zn-xAg-0.5Zr合金中晶界和晶内第二相明显增多,晶粒尺寸逐渐减小;Mg-3.5Sm-0.6Zn-xAg-0.5Zr合金电磁屏蔽效能也随着Ag含量的增加而显著提升.     

A356合金疲劳数据的数理统计分析

研究了不同加钛方式和钛含量对A356合金低周疲劳性能的影响,并重点对实验数据进行了数理统计分析,拟合了四种合金的Manson-Confin方程,分析了实验数据的统计可靠性与显著性。结果表明,A356合金低周疲劳寿命对加钛方式不敏感,其疲劳寿命仅受合金中Ti含量影响。无论电解加钛合金还是熔配加钛合金,Ti含量为0．1％的合金较0．14％的合金具有更优异的低周疲劳性能。     

一种改善锂电池充放电的方法

串联锂电池的自放电不一致,会使电池后期容量很快降低。究其原因主要是每节电池的剩余容量不同,而剩余容量的差异就是容量的损耗。本文针对此问题,提出一种简单实用的方法,即并联充电,串联放电,来有效地解决这个问题。     

Al-Zn-Mg-Cu系合金的微合金化研究进展

鉴于优良的综合性能,Al-Zn-Mg-Cu合金一直是研究和发展的热点。简要回顾了Al-Zn-Mg-Cu系合金的发展过程,说明了Zn、Mg、Cu主要元素在Al-Zn-Mg-Cu合金中的作用,阐述了Cr、Mn、Ti、Zr、Ag、Li、Ni、Sn、Sr等微量元素和稀土在Al-Zn-Mg-Cu合金中微合金化的作用和研究现状。     

Na_2Ti_3O_7@CNT钠离子电池负极材料的性能研究

用低温水热法合成具有高电导率的Na2Ti3O7@CNT纳米复合材料,通过扫描电镜、XRD等手段表明Na2Ti3O7颗粒包覆在碳纳米管表面形成纳米复合材料.在电化学测试中Na2Ti3O7@CNT可逆容量达到210 mAh g-1,并在30C高倍率放电情况下,比容量仍然保持在50 mAh g-1,表明Na2Ti3O7@CNT作为钠离子电池负极材料具有很好的容量和倍率性能.     

Zr-Al基大块非晶合金的晶化动力学效应

Zr65 Al10 Ni10 Cu15, Zr52.5 Al10 Ni10 Cu15 Be12.5 and Zr52.5 Al10 Ni14.6 Cu17.9 Ti5 bulk amorphous alloys were prepared by copper mould casting. The crystallization kinetics was measured by differential scanning calorimeter(DSC) with different heating rates, and the activation energy was calculated using Kissinger equation. The relationship between thermal stability and rate constant of crystallization reaction is discussed on the view of crystallization kinetics, and the effect of small atom Beryllium on thermal stability of bulk amorphous alloys is also studied.     

Effects of surface modification by Ni, Ti and B on electrochemical properties of Mg1.8Cu0.2Ni hydrogen storage alloy

Amorphous alloy Mg1.8Cu0.2Ni was successfully prepared by mechanical alloying (MA) and a series of (n?x)Nix(Ti?B) composites were synthesized by MA. The electrochemical properties of Mg1.8Cu0.2Ni coated by Ni, Ti and B were studied by cyclic charge-discharge, linear polarization curve, and hydrogen diffusion coefficient experiments. Experimental results indicate that Mg1.8Cu0.2Ni-[0.9Ni0.6(Ti?B)] composite which was MA 30 h exhibited the best performance and its initial discharge capacity arrived to 714.1 mAh/g. After 30 cycles the discharge capacity was above 530 mAh/g, which was much higher than that of Mg1.8Cu0.2Ni. And after 100 cycles it holded still 442.1 mAh/g. On all accounts, after modification by Ni, Ti and B, the initial discharge capacity and high-rate discharge ability of the electrode were evidently increased. At the same time, the cycle performance was also improved significantly.     

Al对AB5贮氢电极高温性能的影响

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　ＡＢ5 ｔｙｐｅｈｙｄｒｏｇｅｎｓｔｏｒａｇｅａｌｌｏｙｓｈａｖｅｂｅｅｎｉｎｔｅｎ ｓｉｖｅｌｙｉｎｖｅｓｔｉｇａｔｅｄｓｉｎｃｅｔｈｅｆｉｒｓｔｕｓｅａｓａｎｅｌｅｃｔｒｏｄｅｒｅｐｏｒｔｅｄｂｙＪｕｓｔｉｉｎ 1973[1] .ＴｈｅｃｏｍｍｅｒｃｉａｌＡＢ5ｅｌｅｃｔｒｏｄｅｓｕｓｅｍｉｓｃｈｍｅｔａｌ,ａｌｏｗｃｏｓｔｍｉｘｔｕｒｅｏｆｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓ ,ａｓａｓｕｂｓｔｉｔｕｔｅｆｏｒＬａ ,ｗｈｉｌｅｔｈｅＢ5ｃｏｍｐｏｎｅｎｔｒｅｍａｉｎｓｐｒｉｍａｒ…     

热处理对A356合金力学性能的影响

通过对比实验研究了在相同Ti含量和相同钛硼比Wti/WB时,热处理对以不同加Ti、B方式（电解加钛,熔配加钛,钛盐加钛,电解加钛＋Al-B,熔配＋Al-Ti-B,钛盐加钛＋硼盐）配制的A356合金的冲击韧度的影响。结果表明：T5、T6热处理工艺较大提高了A356合金的强度,明显改善了A356合金的冲击韧度;T5、T6工艺对A356合金的强度、冲击韧度的影响差别较小,T6略优;不同的加钛方式对A356合金冲击韧度有显著的影响,电解加钛合金表现出比其他加钛方式具有更好的韧度。     

Effect of al on behavior of AB5-type metal hydride anodes at elevated temperature

AB₅-type hydrogen storage alloys are the most promising materials used as the anode in commercial Ni-MH secondary battery. It is very important for electrode materials to have a wider operation temperature range. The component Al is the dominant element to control the electrochemical behavior of the AB₅-type alloys at elevated temperature. With the increase of the amount of Al the discharge capacity decreases and the retention of discharge capacity increases with increasing temperature. It is mainly due to the formation of stable and dense surface oxide film Al₂O₃, which inhibits the electrode corrosion and the further oxidation underneath the surface films.     

纳米储氢合金Ml0.7Mm0.3Ni3.7Co0.7Mn0.4Al0.2制作的储氢电极的电化学性能

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｉｔｉｓｗｅｌｌｋｎｏｗｎｔｈａｔｍｅｔａｌｈｙｄｒｉｄｅｓａｒｅａｎｉｄｅａｌｍｅｄｉｕｍｆｏｒｈｙｄｒｏｇｅｎｓｔｏｒａｇｅｄｕｅｔｏｔｈｅｉｒｈｉｇｈｄｅｎｓｉｔｙａｎｄｈｉｇｈ ｐｕｒｉｔｙｏｆｈｙｄｒｏｇｅｎ .Ｈｏｗｅｖｅｒ ,ａｌｌｋｎｏｗｎｃｏｎｖｅｎｔｉｏｎａｌｍｅｔａｌｈｙｄｒｉｄｅｓ ,ｉｎｃｌｕｄｉｎｇｉｎｔｅｒｍｅｔａｌｌｉｃｃｏｍｐｏｕｎｄｓＡＢ5,ＡＢ2 ,ａｎｄＡＢ ,ｈａｖｅｒｅｖｅｒｓｉｂｌｅｇｒａｖｉ ｍｅｔｒｉｃＨ ｄｅｎｓｉｔｉｅｓｎｏｍｏ…     

钛合金镦锻过程温度场的有限元模拟

钛合金热加工窗口比较狭窄,通常热加工工艺很难同时满足各参数要求.本文采用刚塑性有限元法,通过钛合金锭坯镦粗过程进行了有限元模拟,重点分析了锭坯各部分温度的变化规律,尤其是中心区域的温升规律.结果表明:表面散热仅影响锭坯表面有限的范围,整体影响较小;锤头的热传导对锭坯的端面温降影响较大,但区域范围较小,应避免锤头与锭坯的长时间接触;塑性变形热在锭坯中心区域会产生比较大的温升,有可能导致过热,应考虑制定停顿工艺设计,以避免破坏性温升的发生.本文模拟结果可以为钛合金镦粗工艺设计提供参考.     

强流辐照飞机压气机叶片表层成分分析

在加速电压250 kV、束流密度80 A/cm2和150 A/cm2、脉宽40 ns的强流脉冲离子束辐照下,钛基合金叶片表层烧蚀效果显著.对辐照试样表面进行了卢瑟福背散射(RBS)和能量色散的特征X射线谱(XEDS)分析,结果发现辐照后试样表面成分发生改变,其中Mo元素在表面发生明显的富集现象.Al、Mo元素含量的变化可能导致钛合金相结构的改变,从而影响叶片的某些力学性能.     

Ethylene polymerization with novel silicon bridged homo-dinuclear cyanoethyl cyclopentadienyl

Novel homo-dinuclear silicon bridged cyanoethyl cyclopentadienyl complexes of titanium and zirconium (CH3)2Si((η5-C5H3CH2CH2CN)(C5H5)MCl2)2 (M=Ti(1), Zr(2)) were synthesized and developed for the polymerization of ethylene. Compared with their corresponding mononuclear complexes (η5-C5H4CH2CH2CN)(C5H5)MCl2 (M=Ti(3), Zr(4)), the dinuclear complexes had higher catalytic activity. And the polyethylene produced had a higher molecular weight than that obtained with mononuclear catalysts. Effects of conditions on the ethylene polymerization catalyzed by (2)/MAO (methylaluminoxane) were studied in detail. The catalyst showed a very high activity ( >106g PE/mol Zr*h) under low catalyst concentration and high molar ratio of Al/Zr.