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1.
1 INTRODUCTION Silicon and its alloy have been widely applied in such fields as electronic industry, high-temperature structural ceramics, etc. In addition, the researches on silicon and its relevant materials greatly promote the rapid development of modern optics and infor- mation technology. Therefore, more and more at- tention is focused on the structure of silicon, oxide of silicon and the interfaces between silicon and metal or nonmetal. As an ideal passive film on the Si surface, S…  相似文献   
2.
1 INTRODUCTION donor due to the presence of the protonated carboxyl group; (d) it can form short bridges via one car- Coordination polymers are of great interest due to boxylato end or long bridges via the benzene ring[7]. their physical properties and potential applications in We believe that coordination functionality of isoph- functional materials[1~3]. Aromatic polycarboxylic acids thalate can lead to interesting structures. In this com- such as 1,2,4,5-benzenetetracarboxylic acid[4],…  相似文献   
3.
1 INTRODUCTION In recent years, investigations on the com- pounds containing hydrazide or hydrazone moieties have been increased considerably because of their potentially biological activities, especially as poten- tial inhibitors for many enzymes[1~5]. The presence of weak molecular interactions such as hydrogen- bonding controls the conformational and structural features which are important to the drug action[6, 7]. We have synthesized the photochromic compounds of pyrazolone thiosemi…  相似文献   
4.
薄层循环伏安法是研究液/液界面电荷转移的一种新方法,具有简单、快速、易操作的优点。文章回顾了液/液界面电化学的发展历史,介绍了薄层法的实验原理,对其在电化学中的应用和研究进展进行了评述,总结了界面驱动力与电子转移速率的关系。  相似文献   
5.
1 INTRODUCTION 2-Aminochromene is an important class of com- pounds found as the main compounds of many natu- rally occurring products employed as cosmetics and pigments and utilized as potential biodegradeable agro- chemicals[1~3]. In recent years, montmorillonite in natural and ex- changed forms has received considerable attention in different organic syntheses because of its environ- mental compatibility, low cost, high selectivity, reusa- bility and operational simplicity[4], such as …  相似文献   
6.
1 INTRODUCTION Macrocyclic ligands and their metal complexes have received much attention due to their applications in ion transport, ion separation and as models in biomimic researches[1~7]. The synthetic methods of macrocyclic ligands and their metal complexes are mainly divided into three kinds[8]. The first one is synthesizing free ligand, then forming the metal complexes; the second is template synthesis; and the third is synthesizing the end-off or side-off precursor ligand, then c…  相似文献   
7.
分数导数结合傅里叶最小二乘拟合处理含噪音的重迭信号   总被引:5,自引:0,他引:5  
提出了一种含噪音重迭信号的综合处理方法 :先用傅里叶最小二乘法拟合噪音数据 ,然后对拟合后的信号求 2 .5次导数 ,在对模拟数据研究的基础上 ,讨论了求导后峰位漂移及其影响因素 ,给出了一个用于矫正峰位值的经验公式。用该方法对模拟和实际的紫外含噪音重迭信号进行处理 ,结果良好  相似文献   
8.
卢小泉 《分析化学》2007,35(2):292-292
小波变换的概念是由法国从事石油信号处理的工程师J.Morlet在1974年首先提出的并建立了反演公式。它解决了Fourier变换不能解决的许多困难问题,所以被誉为“数学显微镜”,具有分析发展史上里程碑式的意义。本书是分析科学现代方法丛书中的一册,是国内第一本介绍小波分析在分析化学中应用的图书。作者卢小泉教授自1994年始从事小波分析在分析化学中的应用研究,他在自己科研的基础上参阅了国内外大量的有关小波分析的文献后编著此书,书中内容具有很强的针对性和实用性。该书的出版能给分析化学工作者,特别是化学计量学工作者提供一些有价值的参考。  相似文献   
9.
1 INTRODUCTION Recently the series of compounds M3Ln(BO3)3 (M = Sr, Ba and Ln = LaLu, Sc, Y) with space group P63cm or -3R have been reported[1~5], and some of them exhibit interesting optical properties when doped with the active Cr3+ or Yb3+ ions as laser materials. For example, Yb3+-doped Sr3Y- (BO3)3 crystal is a promising laser material for both tunable and femtosecond laser applications[6~8]. The Ba3Y(BO3)3 crystal melts congruently at 1256 ℃ and has a phase transitio…  相似文献   
10.
Six new 4″-benzyloxyimino-4″-deoxyavermectin Bla derivatives were synthesized from avermectin Bla by the selective protection of C-5-hydroxy group,oxidation of C-4″-hydroxy group,and deprotection followed by reaction with O-substituted hydroxylamine hydrochlorides.Their structures were confirmed by IR,~1H NMR,~(13)C NMR and MS.Insecticidal activities of the derivatives against Phopalosiphum pseudobrassicae,Spodoptera exigua and Pluteua xylosteua were evaluated.  相似文献   
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