锌锰干电池正极粉料中氯化铵含量的测定

采用离子选择电极法对锌锰干电池中正极粉料氯化铵含量进行测定。氨气敏选择电极使用一个疏水的气体渗透薄膜 ,把样品溶液和内电极的氯化铵溶液分开。用强碱把样品的 pH值提高到 11以上 ,溶解的氨 [NH3 (aq)和NH+ 4 ]转化为NH3 (aq)。NH3 (aq)通过薄膜扩散并改变内部的 pH值 (由一个pH电极检测 )。内电极溶液中固定的氯化物浓度由一个氯离子选择电极 (作为参比电极 )来检测。本方法具有操作简便、快速、重现性好的特点     

低钴无钴贮氢合金研究的进展

综述了低钴、无钴贮氢合金的研究进展,总结评价了开发低钴、无钴贮氢合金的理论指导-循环稳定性理论和开发低钴无钴贮氢合金的一系列方法,其中包括成分的探索方法和特种工艺的运用及在低钴无钴贮氢合金的研究方面取得的成果。     

21世纪新洁净煤发电技术

效率低下和污染严重是目前我国发电行业存在的普遍问题,面对电力需求不断增长的局面,洁净煤发电技术在我国的推广实施势在必行。着重介绍了21世纪最具发展价值的洁净煤发电新技术。     

电动车续程性能分析数学模型与应用

针对目前电动车普遍存在续程短的情况 ,给出了续程分析的数学模型、分析过程和分析实例 ,以永磁有刷电动机为原动机的车辆 ,分析了在PWM占空比为100 %时 ,最大续程时系统动力特性 ,最后利用最优控制理论 ,分析行车策略与续程的关系 ,并得出了若干重要结论     

超动型长寿命铅蓄电池池的几点建议

报导了国内外起动用长寿命铅酸蓄电池的概况，根据笔多年积累的经验并针对这类电池的应用特点，具体介绍了起动型铅酸蓄电池在原辅材料，零部件，生产设备和制造工艺等方面如何采取有效措施以提高这类电池的使用寿命。     

Contribution of various substrates to total citric acid cycle flux and ]anaplerosis as determined by13C isotopomer analysis and O2 consumption in the heart

A simple relationship between parameters derived from a¹³C NMR isotopomer analysis and O₂ consumption is presented that allows measurement of the absolute rate of acetyl-CoA oxidation and anaplerotic flux in tissues oxidizing a mixture of four substrates. The method was first applied in a study of the effects of work state and -adrenergic stimulation on net acetate oxidation and anaplerosis in the isolated working rat heart. The results demonstrate that the anticipated ratio of 2 between O₂ consumption and TCA cycle flux for hearts oxidizing only acetate holds at low workload when anaplerosis is low, but deviates toward a factor of 3 under high workload conditions when anaplerosis is increased. This analysis was also extended to hearts that oxidize a more physiological mixture of substrates including long-chain fatty acids, acetoacetate, lactate, pyruvate, and glucose. We show that the contribution each substrate makes to total TCA cycle flux can be determined by combined¹³C NMR and O₂ consumption measurements. The present study also demonstrates that stimulation of anaplerosis (by addition of propionate) can significantly alter the relative contribution each substrate makes to total TCA cycle flux. We conclude that if¹³C labeling patterns are selected appropriately, a comprehensive picture of flux through all major metabolic pathways feeding the cycle can be determined in a single experiment even when complex physiological mixtures of substrates are provided.     

提高尖晶石liMn2O4循环性能的研究

通过表面修饰改善尖晶石LiMn2O4的高温循环性能是非常有效的技术手段之一。采取极片整体修饰的方法,将N-乙烯吡咯烷酮-丙烯腈-丙烯酰胺三元共聚物,溶于N,N-二甲基甲酰胺(DMF)后与导电剂乙炔黑混合后在极片表面延流成膜。测试了修饰电极的充放电以及在常温和高温条件下的循环性能,并进行了循环伏安分析。其结果表明经修饰处理后的LiMn2O4电极显示了较好的循环稳定性,但首次充放电存在充放电平台不明显和容量偏低的现象。通过对LiMn2O4电极修饰前后进行的光电子能谱(XPS)分析,可以观察到锰离子的电子结合能发生了明显的变化,表明聚合物与极片中的活性物质之间存在相互作用。     

光电编码器的单片机减振电路设计

分析了光电编码器的振动机理及影响,设计了用单片机进行控制的减振电路。并用FPGA模拟单片机减振电路,给出其仿真波形,从而验证了单片机减振电路的实用性。     

Fabrication and characterization of poly(vinylidene fluoride)–polytetrafluoroethylene composite membrane for CO2 absorption in gas–liquid contacting process

The wetting resistance of poly(vinylidene fluoride) (PVDF) membrane is a critical factor which determines the carbon dioxide (CO₂) absorption performance of the gas–liquid membrane contactors. In this study, the composite PVDF–polytetrafluoroethylene (PTFE) hollow fiber membranes were fabricated through dry-jet wet phase-inversion method by dispersing PTFE nanoparticles into PVDF solution and adopting phosphoric acid as nonsolvent additive. Compared with the PVDF membrane, the composite membranes presented higher CO₂ absorption flux due to their higher effective surface porosity and surface hydrophobicity. The composite membrane with addition of 5 wt % PTFE in the dope gained the optimum CO₂ absorption flux of 9.84 × 10⁻⁴ and 2.02 × 10⁻³ mol m⁻² s⁻¹ at an inlet gas (CO₂/N₂ = 19/81, v/v) flow rate of 100 mL min⁻¹ by using distilled water and aqueous diethanolamine solution, respectively. Moreover, the 5% PTFE membrane showed better long-term stability than the PVDF membrane regardless of different types of absorbent, indicating that polymer blending demonstrates great potential for gas separation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47767.