KBH_4-AgNO_3分光光度法测定3861催化剂中砷

研究了硼氢化钾－硝酸银分光光度法测定3861双金属重整催化剂中砷含量时共存组分的影响．讨论了硫脲络合掩蔽剂的用量及加入顺序．消除了2mg铂的干扰；改换成盐酸介质，调整酸度为3mol／L，消除了3．5mg锡的干扰．对几批催化剂样品中砷的测定，相对标准偏差小于7．5％，加标回收率在103％～107％．     

酷似嗜铬细胞瘤的18例围绝经期高血压临床分析

对18例酷似嗜铬细胞瘤的围绝经期高血压病案进行临床分析。显示女性45～55岁或手术绝经者出现的发作性血压升高及其伴随的头痛、出汗、心悸等症状与嗜铬细胞瘤的阵发性高血压极其相似。临床上应在排除嗜铬细胞瘤等继发性高血压后，考虑围绝经期高血压的可能性。结合性激素、促性腺激素的测定，给予尼尔雌醇和中西药结合疗法，有较好的临床效果。     

丁二酮二肟一茂稀土配合物的合成及表征

合成了七种以丁二酮二肟为配体的一茂稀土配合物，通过元素分析、红外光谱、质谱手段鉴定为二聚体形式。     

稀土硫酸盐催化合成肉桂酸异丁酯

研究了稀土硫酸盐催化肉桂酸与异丁醇的酯化反应,探讨了催化剂用量,酸醇摩尔比和反应时间对酯化反应的影响。适宜条件下,酯产率可达85.6%。     

用面向对象的程序设计方法设计教学评估系统

文本介绍如何利用面向对象的程序设计方法开发制作教学评估系统的方法．     

VMware在UNIX操作系统教学中的应用

VMware虚拟机近年来在计算机教学领域中被越来越广泛地应用,介绍了VMware虚拟机在UNIX操作系统教学中的具体应用。     

第二代典型煤气化技术

第二代煤气化技术是目前最先进的洁净煤利用技术。Lurqi加压气化、Texaco气化、shell气化、Prenflo气化和GSP气化是五种典型的煤气化工艺。它们均采用高温、加压气化工艺,气化指标好,气化效率高并有利于环保。气流床气化是发展现代大型煤化工项目的首选工艺。     

关于Chebyshev-Legendre表示及Matlab实现变换的

在使用Chebyshev与Legendre耦合的谱方法求偏微分方程的数值解时，最耗费计算机时的是Chebyshev—Leg—endre变换。因此，如何有效地实现Chebyshev-Legendre变换就是一个重要的问题。本文讨论了Chebyshev-Legendre变换的数学表示以及数值实现。     

Carbon deposition in porous nickel/yttria-stabilized zirconia anode under methane atmosphere

A commercial solid oxide fuel cell with a Ni/YSZ anode was characterized under a pure methane atmosphere. The amount of deposited carbon increased with an increase in temperature but decreased when the temperature exceeded 700°C. The reactivity of carbon decreased with increasing deposition temperature. Filamentous carbon was deposited from 400 to 600°C, whereas flake carbon was deposited at 700 and 800°C. With increasing temperature, the intensity ratio of the D band over the sum of the G and D bands was constant at the beginning and then decreased with the transformation of the carbon morphology. The crystallite size increased from 2.9 to 13 nm with increasing temperature. The results also indicated that the structure of the deposited carbon was better ordered with increasing deposition temperature. In comparison with pure Ni powders, the interaction between the YSZ substrate and Ni particles could not only modify the carbon deposition kinetics but also reduce the temperature effect on the structure and reactivity variation of carbon.     

动力学控制合成原子精确的银纳米团簇及催化还原4-硝基苯酚

Synthesizing atomically precise Ag nanoclusters (NCs), which is essential for the general development of NCs, is quite challenging. In this study, we report the synthesis of high-purity atomically precise Ag NCs via a kinetically controlled strategy. The Ag NCs were prepared using a mild reducing agent via a one-pot method. The as-prepared Ag NCs were confirmed to be Ag₄₉(D-pen)₂₄ (D-pen: D-penicillamine) on the basis of their matrix-assisted laser desorption ionization time-of-flight mass spectrometric and thermogravimetric characteristics. The interfacial structures of the Ag NCs were illustrated by proton nuclear magnetic resonance and Fourier-transform infrared spectroscopy. The Ag NCs were supported on activated carbon (AC) to form Ag NCs/AC, which displayed excellent activity for the catalytic reduction of 4-nitrophenol with a kinetic reaction rate constant k of 0.21 min?1. Such a high k value indicates that the composite could outperform several previously reported catalysts. Moreover, the catalytic activity of Ag NCs/AC remained nearly constant after six times of recycle, which suggests its excellent stability.