微纳米纤维素功能膜在能源与环境领域的应用

探寻绿色清洁的资源与材料以维持高效的社会经济增长是未来数十年人们面临的最大挑战之一. 可持续资源与绿色材料的开发是降低传统化石能源与材料比重的最有前途的方案. 纤维素作为一种可持续发展、 可生物再生、 储量丰富且低成本的天然高分子聚合物, 在众多领域中具有广泛的应用, 并且纤维素可以加工成各种构型, 包括气凝胶、 泡沫、 海绵和薄膜等. 本文介绍了不同形态的纤维素及其衍生物组装而成的功能膜在能源与环境中的应用, 综述了微纳米纤维素及其衍生物在先进功能化储能器件方面的最新进展和制备方案, 以及在用于水处理的膜分离技术中的应用, 其中重点讨论了微纳米纤维素及其衍生物功能膜在电池、 电容器及水处理等领域中的作用, 如隔膜、 柔性电极膜和分离膜等. 此外, 还对纤维素及其衍生物功能膜的未来发展进行了总结和展望.     

自支撑硫镍基电极材料制备及其赝电容性能

硫镍基赝电容超级电容器具有较高的比电容和功率密度等优点,是下一代理想的储能装置之一,但其实际应用受到其活性材料的制约,如导电性低和循环性能差等。研究者围绕增强硫镍基赝电容电极材料导电性和提升循环稳定性进行了大量的研究工作。其中,构建自支撑的电极材料被认为是一种降低活性材料和集流体之间界面电阻的有效方法。本文综述了制备自支撑硫镍基赝电容电极的常见方法,并就活性材料的形貌与性能关系进行了总结,主要着眼于集流体改性、离子掺杂、复合材料构建及形貌调控优化等。最后对自支撑硫镍基赝电容电极材料的研究方向进行了展望。     

壳聚糖混合膜酶降解的FTIR分析

生物可降解性是壳聚糖的重要性质之一,但利用傅里叶变换红外光谱(FTIR)研究降解过程中壳聚糖的变化则较少。文章制备了由高脱乙酰度壳聚糖(HDC)和中脱乙酰度壳聚糖(MDC)组成的混合膜。运用FTIR分析了壳聚糖混合膜组分变化对其红外谱图和脱乙酰度(DD)的影响,并研究了该混合膜在溶菌酶的降解作用下红外谱图和脱乙酰度的变化。发现壳聚糖混合膜材料的脱乙酰度与膜中MDC组分的比例呈线性关系;随降解的进行,混合膜的脱乙酰度增加。结果证实了溶菌酶对较低脱乙酰度壳聚糖的选择性降解作用,而且表明FTIR可用于分析壳聚糖混合膜降解过程中的化学变化。     

基于互连线电容耦合的SR锁存电路研究

通过对线间电容耦合模型的研究, 提出了一种基于互连线电容耦合的SR锁存电路设计方案. 该方案首先分析互连线间电容耦合关系, 利用MOS管栅极电容模拟互连线电容; 然后利用电容耦合结构与线计算特性, 设计或非逻辑门电路, 在此基础上实现基于互连线电容耦合的SR锁存电路; 最后在TSMC 65nm Spectre环境下仿真验证. 结果表明 所设计的电路逻辑功能正 确, 且具有低硬件开销特性.     

Gate-induced drain leakage (GIDL) in MFMIS and MFIS negative capacitance FinFETs

The gate induced drain leakage (GIDL) effect in negative capacitance (NC) FinFET is investigated. A Landau–Ginzburg–Devonshire equation (which considers the polarization gradient in ferroelectric material) is used to estimate the characteristics of the NC FinFET. Specifically, metal-ferroelectric-metal-insulator-semiconductor (MFMIS) and metal-ferroelectric-insulator-semiconductor (MFIS) NC FinFETs are compared, in order to figure out the effect of the internal metal layer on the GIDL effect. To analyze the impact of the polarization gradient on the GIDL effect in NC FinFET, a polarization gradient coefficient is varied. For MFMIS, the polarization gradient doesn't significantly affect the device performance. The subthreshold swing improves but the GIDL effect deteriorates because of the “uniform” NC effect in channel region. For MFIS, the device performance is explicitly affected by the polarization gradient. Smaller polarization gradients result in non-uniform NC effect in channel region, resulting in severe GIDL effects. On the other hand, higher polarization gradients alleviate GIDL effects.     

用于神光Ⅲ原型装置20 kJ能源系统的研制

在神光Ⅲ原型棒状放大器能源系统中,采用LC串联谐振变换器构成的软开关式恒流充电单元设计了高精度充电机.同时,基于RLC串联谐振电路的临界阻尼特性,设计了脉冲成形单元.分析了氙灯非线性解决办法及内触发点灯方式的可靠性,得出了脉冲氙灯线形等价和触发脉宽影响点灯可靠性的结论.采取计算机远程集中控制的控制策略,使得该系统控制安全高效.设计的20套能源模块完全符合用户要求,说明该方案具有可行性.     

The adsorption structure of nonionic surfactant on the sessile mercury electrode in a thin liquid film

In relation to a colloid stability, the adsorption structure of the Stern layer on a sessile mercury electrode in a thin liquid film of nonionic surfactant was investigated by measuring the double layer capacitance. The Stern capacitance on the electrode in the film could be detected when the measuring frequency used was low, for the resistance of the film was not extremely high but of the order of several thousand ohm. It was found that the adsorption structure of nonionic surfactant in the thin liquid film shows a stratification different from that of bulk.     

An impedance study of Ir(210) in HCl solutions

In the Ir(210)/aqueous HCl solution system the “hydrogen adsorption region” is due to the combined process of hydrogen and chloride ion adsorption. We demonstrate that by using impedance spectroscopy the rates of, and charges associated with, hydrogen and chloride adsorption rates can be determined separately. Published in Elektrokhimiya in Russian, 2009, Vol. 45, No. 1, pp. 32–41. Dedicated to the 100th anniversary of B.V. Ershler. The text was submitted by authors in English.     

Preparation and characterization of PLGA particles for subcutaneous controlled drug release by membrane emulsification

Uniformly sized microparticles of poly(d,l-lactic-co-glycolic) (PLGA) acid, with controllable median diameters within the size range 40–140 μm, were successfully prepared by membrane emulsification of an oil phase injected into an aqueous phase, followed by solvent removal. Initially, simple particles were produced as an oil in water emulsion, where dichloromethane (DCM) and PLGA were the oil phase and water with stabiliser was the continuous phase. The oil was injected into the aqueous phase through an array type microporous membrane, which has very regular pores equally spaced apart, and two different pore sizes were used: 20 and 40 μm in diameter. Shear was provided at the membrane surface, causing the drops to detach, by a simple paddle stirrer rotating above the membrane. Further tests involved the production of a primary water in oil emulsion, using a mechanical homogeniser, which was then subsequently injected into a water phase through the microporous membrane to form a water in oil in water emulsion. These tests used a water-soluble model drug (blue dextran) and encapsulation efficiencies of up to 100% were obtained for concentrations of 15% PLGA dissolved in the DCM and injected through a 40 μm membrane.

Solidification of the PLGA particles was followed by removal of the DCM through the surrounding aqueous continuous phase. Different PLGA concentrations, particle size and osmotic pressures were considered in order to find their effect on encapsulation efficiency. Osmotic pressure was varied by changing the salt concentration in the external aqueous phase whilst maintaining a constant internal aqueous phase salt concentration. Osmotic pressure was found to be a significant factor on the resulting particle structure, for the tests conducted at lower PLGA concentrations (10% and 5% PLGA). The PLGA concentration and particle size distribution influence the time to complete the solidification stage and a slow solidification, formed by stirring gently overnight, provided the most monosized particles and highest encapsulation efficiency.     

纳米四氧化三锰温和水相合成及其电容性能

采用温和水相合成法制备出纳米Mn3O4,采用X射线衍射（XRD）、电子能谱（XPS）及透射电子显微镜（TEM）等技术手段对其结构、组成与形貌进行了研究分析;并利用循环伏安（CV）及充放电等电化学测试研究了纳米Mn3O4的电容性能。 结果表明,本实验所制备的纳米Mn3O4为四方相γ-Mn3O4,其粒径大小为40~60 nm;该材料具有良好的电容性能,其比电容值可达270 F/g,且经1000次循环后,其比电容值可达原来的85%。