氢镍电池陶瓷密封极柱正压氦检方法研究

高压氢镍电池陶瓷极柱的密封性是影响电池性能的主要原因之一。设计了一种陶瓷极柱的正压氦检方法,有效提高了极柱的检漏水平,从而进一步提高了氢镍电池使用的可靠性。     

金属粉末添加剂对锌镍电池正极性能的影响

通过物理添加方式向锌镍电池正极活性物质氢氧化镍[Ni(OH)_2]中混入银粉、铜粉和钴粉等金属粉末。用极化曲线、电化学性能测试和SEM分析对试样进行研究。银粉对镍电极性能的提升作用好于铜粉;银粉和钴粉能提高电极的耐腐蚀性能,且添加钴粉的镍电极在6 mol/L KOH+10 g/L LiOH溶液中的缓蚀效率最高,铜粉会加速电极腐蚀。综合考虑,添加钴粉的镍电极性能最优,适宜的添加量为5%。该电极以0.2 C充放电(充电6 h,放电至1.2 V),前30次循环的循环保持率为89%,最大放电比容量为247.7 mAh/g。     

镍渣矿渣免烧砖的试验研究

研究了镍渣矿渣比和水泥掺量对镍渣矿渣复合胶凝材料体系的影响,并在此基础上,辅以化学激发剂NS、CA,采用正交试验方法,研制开发新型镍渣矿渣基复合胶凝材料,最佳配比为:镍渣和矿渣的质量比5∶5,水泥、激发剂NS和CA分别占镍渣和矿渣总质量的20％、0.5％和2％,胶砂比1∶3,水胶比0.5,可制得符合MU25等级的免烧砖.     

水性镍系内墙电磁屏蔽涂料

用导电镍粉与丙烯酸乳液为主要原料,制备了水性镍系内墙电磁屏蔽涂料.采用扫描电镜(SEM)对导电镍粉以及涂层的微观形貌进行了表征,研究了无机改性膨润土对涂料沉降率的影响,并对其机理进行了探讨;对涂料中挥发性有机化合物(VOC)以及游离甲醛的含量进行了测定,在30~1000 MHz频段范围内,对涂料涂层在远场区(平面波)与近场区(电场)的屏蔽性能进行了测试,并对不同区域屏蔽性能的差异进行了分析.     

How cryogenic techniques help in machining of nickel alloys? A review

Nickel alloys are extensively used in aerospace, automotive, marine, nuclear, petro-chemical and food processing industries due to properties like high strength, resistance to heat, resistance to corrosion, etc. However, machining of these alloys pose many challenges in machining such as: work hardening, high temperatures at the cutting zone, rapid tool wear, reduced tool-life, etc. Attempts are made to overcome these challenges by using various cryogenic techniques. This paper, therefore discusses different techniques such as cryogenic cooling, cryogenic treatment of tool and simultaneous use of cryogenic cooling of tool and heating of workpiece (hybrid technique) and their effects on machinability of Nickel alloys with the help of indicators like tool-life, surface roughness, residual stresses, etc. It is concluded that cryogenic techniques are helpful in improving the machining performance by way of improvement in tool-life and surface quality. This happens due to better cooling by cryogen and improved tool properties after cryogenic treatment. However, based on the published works, it is not possible to decide about the following: correct amount of cryogen required for cooling, appropriate cryogenic tool treatment cycle to be used and the best parameters for machining of Nickel alloys. Therefore, future research should focus on these aspects.     

Microwave irradiated and thermally heated olive stone activated carbon for nickel adsorption from synthetic wastewater: A comparative study

In attempt to compare the removal efficiency and yield of the activated carbon prepared using the conventional and microwave‐assisted heating is the focus of this work. Toward this olive stone (a biomass precursor) is activated using the popular activating agent potassium hydroxide. The process optimization exercise is carried out by using the standard full factorial statistical design of experiments (response surface methodology). The activated carbons prepared under the optimized conditions are compared based on the adsorption capacity and yield. The adsorption capacity was found higher using microwave heating as compared with conventional heating. The microwave heating requires significantly lesser holding time as compared to conventional heating method to produce activated carbon of comparable quality, with higher yield. The BET surface area of carbon using microwave heating is significantly higher than the conventional heating. Although the mesopore surface area of carbon is not vary significantly, the activation time, power, and nitrogen gas consumption are significantly lower than the conventional heating rendering that the activation process via microwave is more economical than that via conventional heating. The adsorption isotherm data fitted the Langmuir isotherm well and the monolayer adsorption capacity was found to be 12.0 and 8.42 mg/g for microwave and thermally heated activated carbon, respectively. Regeneration studies showed that microwave‐irradiated and thermally heated olive stone could be used several times by desorption with an HCl reagent. Both carbons can be used for the efficient removal of Ni²⁺ (>99%) from contaminated wastewater. © 2013 American Institute of Chemical Engineers AIChE J, 60: 237–250, 2014     

稳定超疏水镍基涂层的制备及其耐蚀性

目的 在金属表面制备稳定的超疏水镍基涂层,以提升金属的耐蚀性。方法 通过电沉积方法先后在金属表面获得具有微纳结构的多孔镀镍层和聚硅氧烷层。通过扫描电子显微镜、X射线粉末衍射仪、X射线光电子能谱、傅里叶变换红外光谱仪、接触角测定仪、电化学工作站等对涂层的形貌、成分、疏水性和耐蚀性进行表征。结果 乙二醇的添加能够促进电镀镍时阴极氢气的析出,当乙二醇的添加量为50.0～100.0mg/dm³时,形成了均匀相互连接的多孔镍镀层;在水解后的硅氧烷溶液中、-1.5 V电压下沉积3.0 min,可形成具有自清洁性能的超疏水膜层,其表面水接触角达到(159±1)°。在质量分数为3.5%的氯化钠溶液中,涂层的腐蚀电流密度约为3.6×10^-8A/cm²,与未修饰的镍镀层相比降低了3个数量级;低频阻抗模值|Z|0.01Hz为2.0×10⁶Ω·cm²,与未修饰的镍镀层相比,提升了3个数量级;在磨损实验后,涂层的微纳米结构依旧存在,保持着超疏水能力,其腐蚀电流密度和|Z|0.01 Hz分别为5.3×10...     

镀镍层的汗渍腐蚀及防护

镀镍层对手汗渍非常敏感,容易形成汗渍性指纹腐蚀。经过试验研制了镀镍层专用的水性LP-1068C和溶剂型SP-2068C防汗渍性指纹的电接触润滑保护剂。其作用是防止钢铁和铝基体腐蚀,保护镀层不失光泽,并能充当镀镍后脱水材料,同时保持和保护镀镍层固有的电气性能。试验表明:只有使用具有协同效应的保护材料,才能起到防汗渍性指纹的保护作用。     

电镀污泥中铜镍锌元素的检测

对电镀污泥的样品采集、样品制备以及电镀污泥中铜、镍、锌元素的检测方法进行了研究和优化改进。对铜、镍和锌的分析方法的精密度进行了加标回收实验,加标回收率为97%~105%。对方法的准确度与先进的电感耦合等离子体原子发射光谱法检测结果进行对比,结果显示,该方法操作较为简单,检测成本较低,可准确判断电镀污泥中铜、镍和锌含量。     

钙离子对化学镀镍溶液性能的影响

研究了钙离子对化学镀镍镀液的影响,测试了10、30和150mg/L的钙离子对镀液的寿命、稳定性及沉积速率的影响。结果表明,随着镀液中钙离子质量浓度的升高,镀液稳定性下降,使用寿命减短;同时还测试了钙离子对镀层结合力、耐蚀性、耐磨性及镀层显微形貌的影响。结果显示,随着钙离子质量浓度的升高,镀层耐蚀性及光亮性变差,结合力降低。钙离子对化学镀镍具有较大的影响,故在实际生产过程中应严格控制化学镀镍溶液中钙离子的质量浓度。