碳纳米管包覆空心羟基铁粉的制备及其磁性能

采用点蚀法处理羟基铁粉(hydroxy-iron,HI),制备出具有空心结构的羟基铁粉(h-HI),以对氨基苯甲酸(PABA)作为活性嫁接剂连接空心羟基铁粉与碳纳米管,制备出碳纳米管包覆的空心羟基铁粉(MWCNTs@h-HI)。使用XRD、SEM、TEM及Lakeshore 7307型振动磁强计对样品进行表征和分析。结果表明,通过点蚀处理可制得空心羟基铁粉,当点蚀时间为15 min时,空心羟基铁粉产率最大,粒径约为2μm的空心羟基铁粉的壁厚范围为200 nm,包覆层厚度约为150 nm。碳纳米管包覆空心羟基铁粉的饱和磁化强度(M_s)为140.88(A·m2)·kg~(-1),剩磁(M-r)为1.4808(A·m~2)·kg~(-1),矫顽力(H_c)为4.742×10~(-3)T。     

Pt/graphite catalyst for hydrogen generation by HI decomposition reaction in S–I thermochemical cycle

Hydrogen is an attractive energy carrier for future because of various reasons. Therefore its large scale production is the need of the hour. One of the ways to achieve this is sulfur iodine thermochemical cycle and HI decomposition reaction is one of the three reactions constituting the cycle. Pt/graphite catalysts with different loading of platinum were prepared by impregnating colloidal graphite with hexachloroplatinic acid solution followed by reduction under N₂ flow. The catalysts prepared have been characterized by X‐ray diffraction, Raman, scanning electron microscopy, X‐ray photoelectron spectroscopy and Brunauer–Emmett–Teller surface area. These catalysts have been employed for liquid phase HI decomposition under different conditions. To evaluate the stability of this catalyst against noble metal leaching under the reaction conditions, the eluent was analyzed by using ICP‐OES. Platinum loaded catalysts (0.5%, 1% and 2%) show 8.4%, 17.5% and 23.4% conversion respectively. From the present study we conclude that Pt/graphite is a suitable and stable catalyst for liquid phase HI decomposition reaction. Copyright © 2015 John Wiley & Sons, Ltd.     

基于水泥净浆流变性的振动-剪切等效理论

为了分析振动条件下水泥净浆的流变特性,解释水泥净浆流变性模型的转化机制,提出适用于振动条件下水泥净浆流变性分析的振动-剪切等效理论. 根据修正HI理论和回转黏度仪径向分层算法,计算振动条件下回转黏度仪内水泥净浆流场的剪切速率,将振动台正弦振动过程转化为对水泥净浆的剪切过程. 采用自制回转黏度仪,开展20 Hz振动频率下的HI参数标定试验和30 Hz振动频率下的水泥净浆黏度试验. 结果表明,HI参数标定结果与数值计算结果之间的误差约为7%,水泥净浆的试验黏度与数值计算的黏度之间的误差为8%并趋于收敛状态. 增大振动频率,水泥净浆的黏度逐渐减小并达到峰值,流变性模型逐渐由Bingham模型转变为Hershel-Bulkley模型,最后转变为Power-Law模型.     

基于Linphone的海思H.264硬件编码器移植

为了缩短H.264编码时间、提高H.264编码效率,提出基于Android Linphone的Hi3716MV400 H.264硬件编码器移植.对硬件编码器的移植方法进行详细说明,包括搭建Linphone开发环境、添加Hi3716MV400 H.264硬件编码库、编写H.264硬件编码函数.经程序测试,移植了海思H.264硬件编码器的Linphone能够在Hi3716MV400机顶盒进行正常的视频通信,并且减少CPU资源占用,降低Linphone视频通话死机频率.     

功能高分子亚氨基二乙酸树脂对钕的吸附行为研究

本文用亚氨基二乙酸树脂(D401)采用静态的方法吸附钕(Ⅲ),获得一些参数以指导实际应用.结果pH=5.73为最佳吸附pH;298K时每克树脂的静态饱和吸附容量179mg;用2.0mol·L-1HCl解吸,解析率达100%;等温吸附服从Freundlich经验式;298K时的表观速率常数k298=2.22×10-5s-1;吸附反应的焓变为ΔaHm= 18.8kJ·mol-1;D401对钕(Ⅲ)吸附反应的表观吸附活化能为51.3kJ·mol-1;树脂功能基与钕(Ⅲ)的配位比为3:1;用红外光谱探讨了该树脂和钕(Ⅲ)的成键情况.     

壬基酚聚氧乙烯醚的裂解及定量测定

采用氧碘酸对壬基酚聚氧乙烯醚NPnEO进行裂解处理.通过GC-MS测定裂解产物中壬基酚NPs的含量.正交实验[L9(34)]表明温度、裂解时间是影响裂解效果的主要因素.实验中优化后的裂解条件为:温度100～105 ℃、次磷酸钠用量0.5～1.0 g、氢碘酸浓度36%、时间14～15 h,该条件下测试结果的重现性(RSD)为9.4%.采用该条件对5类皮革用化工材料中NPnEO进行定量测试,2类样品中NPnEO含量显著.     

一种基于HI6110 的1553B BM 板卡设计方法

针对军用航空领域对1553B板卡的巨大需求,提出一种基于H16110的J553BBM板卡设计方法。在介绍1553B总线以及H16110芯片的基础上,从处理器设计、H16110设计、FPGA设计、FLASH设计方面进行了硬件设计,并给出了软件功能模块及软件流程。实际应用结果证明：该方法可靠性高,与其他设计方法相比具有成本低等优势。     

兼顾供电可靠性和LCC的变电站主设备检修策略优化方法

提出了一种能够同时兼顾变电站供电可靠性和设备全寿命周期成本(LCC)的设备检修决策优化方法。该方法选择变电站中的待检变压器和断路器,利用健康指数(HI)和役龄回退因子分别计算待检设备检修前后的故障率;通过变电站的预想事故分析和负荷削减状态的枚举,计算设备检修前后变电站电量不足期望(EENS)和设备LCC的变化量;最后,分别给出以可靠性优先、经济性优先和费效比优先作为评价指标的优化检修策略。某220kV变电站的检修决策实例表明,该方法能够综合考虑变电站的供电可靠性和设备的LCC,制定合理有效的检修策略。在有效降低变电站供电风险的前提下提高设备检修效率,减小检修维护成本。     

Effects of Ce/Zr composition on nickel based Ce(1−x)ZrxO2 catalysts for hydrogen production in sulfur–iodine cycle

In this study, 5%Ni/Ce_(1−x)Zr_xO₂( x = 0, 0.2, 0.5, 0.8, 1) catalysts were prepared by sol–gel method and tested for hydrogen iodide (HI) decomposition in sulfur–iodine (SI) cycle. The effects of zirconia incorporation were subsequently examined by a series of characterization methods. In comparison with the blank test, all of the catalysts, particularly Ni/Ce_0.8Zr_0.2O₂, remarkably enhance the HI decomposition. Therefore, adding a small amount of zirconia results in the highest catalytic activity, which could be attributed to the following three effects: increase in oxygen mobility and oxygen vacancy, stronger interaction between NiO and the supports. The oxygen mobility and oxygen vacancy are dominant in the HI decomposition. The strong interaction between NiO and the supports accelerates the oxygen transfer from the bulk to surface, which could also enhance the decomposition. However, excessive zirconia content has negative effects, which is due to the decrease in oxygen mobility and surface area. The poor thermal stability in zirconia-rich supports also restricts catalytic performance. In addition, a hypothetic mechanism of HI catalytic decomposition over Ni/Ce_(1−x)Zr_xO₂ is proposed.     

ITO dry‐etching mechanism and its application in the fabrication of LCDs

Abstract— Based on HI gas‐plasma etching (high‐density plasma‐assisted RIE), the activation energy for an ITO dry‐etching reaction was obtained. The value was calculated 35–40 kJ/mol for 20 sec from the reaction starting time. The reaction dead time is characteristic of the ITO dry‐etching process, but the reaction is relatively simple. Therefore, ITO dry‐etching technology, based on HI gas plasma, is useful in the the fabrication of LCDs, and was used in a recently developed Multi‐Coaxial‐Plasma‐Source (MCPS) dry etcher.