Pt-Sn-K/Al2O3催化剂上长链烷烃(C17～C20)脱氢反应工艺条件

以C17～C20重蜡脱氢为探针反应,考察反应温度、反应压力、氢烃体积比及空速等工艺参数对Pt-Sn-K/γAl(2)O(3)催化剂脱氢反应性能的影响.结果表明,C17～C20脱氢反应适宜的工艺条件为:反应压力0.14 MPa,氢烃体积比600:1,空速20 h-1和反应温度高于440℃,此条件下,转化率达14%以上.     

电力企业技术合同管理中营业税筹划的实践分析

基于国家对企业营业税的有关税收优惠政策的研究,以电力高新技术企业为例,指出应形成规范的技术合同并进行合理分类,通过税收筹划,使电力企业得以享受国家鼓励技术创新与促进科技成果转化的税收优惠政策.     

基于最小割集的含环网配电系统可靠性评估

针对目前部分高压配电网采用少环网运行方式的情况,基于最小割集理论,提出了一种适用于含环网的配电系统可靠性评估方法。基于寻找节点组元件的方法模拟了元件的活动性故障,采用基于补偿法的少环配电网潮流计算方法。考虑了元件的容量约束,并同时计及了元件的计划检修和备用电源的影响。对RBTS-BUS4系统及实际工程系统进行了可靠性评估,结果表明该算法能计算出系统和负荷节点的可靠性指标,识别出系统的薄弱环节。     

卡拉胶硬胶囊

<正>硬胶囊系指已大规模生产的空胶囊,它是由两个部分(胶囊帽和胶囊体)组成的,只在生产后装填内容物,然后组合和密封在一起。硬胶囊在大多数情况下是用单相水溶液以所谓的蘸胶法加工过程生产的。     

Adsorption and drug release based on β‐cyclodextrin‐grafted hydroxyapatite composite

In this study, β‐cyclodextrin (β‐CD) was covalently grafted on hydroxyapatite (HA) using a coupling agent to improve the drug loading capacity and prolong the drug release. The binding of β‐CD on the HA surface was confirmed by Fourier transformation infrared spectroscopy, thermal gravimetric analysis, and X‐ray powder diffraction. The adsorption capacity of ofloxacin on β‐CD‐grafted hydroxyapatite (β‐CD‐g‐HA) composite was found to be 30 mg g^?1 at 37°C and 24 h. The adsorption process is spontaneous, given the negative values of free energy change. Compared with the release of ofloxacin loaded on HA, the release of ofloxacin loaded on β‐CD‐g‐HA was slowed down 28% and 21% in pH 2.0 and pH 7.4 buffer media at 2 h, respectively. Biocompatibility of β‐CD‐g‐HA was assessed by MTT assay, and the result showed that it had no cytotoxicity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Characterization and anticorrosive properties of poly(2,3‐dimethylaniline)/Na+‐montmorillonite composite prepared by emulsion polymerization

Composites of Poly(2,3‐dimethylaniline) and inorganic Na⁺‐montmorillonite clay were synthesized by emulsion polymerization. The as‐synthesized composites (PDMA) were characterized by Fourier Transform Infrared Spectroscopy, X‐ray diffraction, and scanning electron microscopy. The protective performance against corrosion of the samples was evaluated by Tafel and electrochemical impedance spectroscopy measurements. The results showed that the composite containing 5 wt. % of clay loading (PDMA‐5%) displayed a better anticorrosive performance than other samples. The Epoxy(E) blend with PDMA‐5% (EPM5) coating was founded to have a higher corrosion potential and a lower current density than that of Epoxy blend P(2,3‐DMA) (EP) coating. The impedance value of EPM5 coating was about 6.68×10⁶Ω·cm² in 5 wt. % NaCl solution even after 288 h, compared to EP (4.26×10⁵Ω·cm²) coating, which went to show that the corrosion inhibition of P(2,3‐DMA) could be effectively enhanced by incorporating MMT into the P(2,3‐DMA) matrix. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4528–4533, 2013     

噁草酮在水稻及其环境中的残留分析方法

[目的]采用气相色谱法建立噁草酮在水稻及其环境系统中的残留分析方法。[方法]探索了水稻及稻田环境中噁草酮残留量的GC-ECD分析方法,样品均用二氯甲烷提取,二氯甲烷萃取,层析柱净化后经GC-ECD测定。[结果]噁草酮的最小检出量为1.0×10-12g(以3倍信噪比计),在上述噁草酮残留量分析测定条件下,噁草酮的最低检出质量浓度分别为稻田水0.005 mg/L,土壤、植株、糙米和稻壳中0.005 mg/kg。水样、土样、植株、稻米和稻壳中甲维盐的添加回收率83.08%~106.11%,变异系数1.14%~9.20%。[结论]均符合农药残留分析方法的技术要求。     

Electrorheological properties of poly[N,N′-(2-amino-5-carboxybutyl-1,3-phenylenedimethylene)-2,2′-diamino-4,4′-bithiazole]

Poly[N,N′-(2-amino-5-carboxybutyl-1,3-phenylenedimethylene)-2,2′-diamino-4,4′-bithiazole] was synthesized and characterized with Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Anhydrous electrorheological (ER) fluids were prepared using the polymer particles as disperse phase and bromodiphenylmethane as a disperse medium. Rheological measurements were carried out via a rotational rheometer to investigate the effects of electric field strength and the polymer particle content on the ER properties. Results indicate that suspensions of the polymer particles containing amino and carboxybutyl groups in bromodiphenylmethane exhibit a substantial ER effect.     

X射线管结构与焦斑关系研究

X射线管是X射线机的心脏,是产生X射线的源泉<参考文献原文>。其焦斑大小及分布对整机图像清晰度起着决定性的作用。通过对X射线管结构特点、焦斑产生机理、电极结构与焦斑相关性实验的测试数据及理论分析等多方面的论述,探讨了X射线管结构尺寸对焦斑的影响。通过系列实验及理论分析表明:X射线管阴极结构对焦斑有巨大的影响。借助计算机模拟仿真计算,合理设计阴极结构,能够获取大小适中、分布均匀的焦斑,从而达到改善X射线机图像清晰度的目的。     

大芯径光纤基模功率传输特性与折射率分布形式关系的研究

研究和分析了光纤芯区径向折射率分布对大芯径光纤基模的功率传输特性(主要包括最大功率密度和等效模面积这两个参数)的影响。采用一种可适用于多种光纤实际折射率分布的独特数学表达式,研究了折射率分布形状变化时大芯径光纤基模在横截面内功率密度分布与等效模面积的变化,并将结果与阶跃型折射率光纤进行对比。计算结果表明,在传输功率相同、光纤基模与高阶模等效折射率差大于10-4的前提下,折射率在芯区中心有一定凹陷的分布可以有效降低横截面内基模功率密度的最大值,增大基模的等效模面积。这一研究为设计和制作可以传输更大功率的大芯径的无源和有源单模光纤提供了理论基础。