利用氧化加成反应合成双核铜（Ⅱ）配合物及其晶体结构

利用氧化加成反应合成双核铜（Ⅱ）配合物及其晶体结构杨瑞娜，胡晓院，金斗满（河南化学研究所，郑州４５０００３）氧化加成反应在生命过程、分子催化等领域中均十分重要￣［１］，而许多与氧化加成反应有关的催化反应中，铜配合物常被用作催化剂￣［２］，因此，这一领...     

双核铜配合物的合成、结构和性质研究

双核铜配合物的合成、结构和性质研究＊杨瑞娜薛宝玉王冬梅侯益民金斗满（河南化学研究所，郑州４５０００３）李彩云（平原大学，新乡４５３００３）关键词铜双核配合物氧化加成中图分类号Ｏ６２７．１２众所周知，许多金属酶具有铜（Ⅰ）、铜（Ⅱ）活性中心，铜配合物具...     

氯化亚铜中亚铜及高价铜盐含量的示波滴定

１引言氯化亚铜含量的测定在国家标准分析方法中是根据亚铜离子能使Ｆｅ３＋还原为Ｆｅ２＋，然后以邻菲啉－硫酸亚铁络合物作指示剂用高铈盐进行滴定。氯化亚铜中高价铜盐测定则利用高价铜盐能溶于５ｍｏｌ／Ｌ乙酸．而亚铜盐不能溶解进行分离，然后再用碘量法进行测定，手续十分麻烦。本文根据ＣＵ（Ⅰ）与四苯硼钠定量生成沉淀，用示波滴定法中的四苯硼钠法进行氯化亚铜含量的测定，高价铜盐被抗坏血酸还原，再用四苯硼钠法进行滴定，差量法计算出高价铜盐含量，操作简便，终点直观，测定结果准确。２实验部分２．１主要仪器与试剂ＬＳ－…     

微量元素锌铜铁与心血管病的研究

心血管疾病患者体内的微量元素存在的显著的异常变化，这在许多的实验研究和临床观察中得到证实，本文根据近年国内外的文献资料，概述了微是元素锌，铜，铁生理作用及与心血管疾病的关系。     

支气管灌洗液中铜锌含量及铜／锌比值的观察

用原子吸收光谱法检测了肺癌患者灌洗液中铜、锌含量及铜／锌比值。结果表明：中央型肺癌组与肺部良性疾病组比较均有极显著差异；与周围型比较，铜、铜／锌具有显著性差异；而周围型肺癌组与良性组比较，除铜／锌比值有显著性差异，Ｃｕ、Ｚｎ均无统计学意义差异。     

微量元素铜与人体生理功能和疾病

铜是人体中重要的微量金属元素之一，在多种生命活动中起着不可或缺的作用，包括电子传递、线粒体功能以及多种酶的活性。铜的缺乏或过量都会对人体产生严重、甚至是致命的危害，所以铜的摄取、胞内组装和代谢都需要严格的调控。铜的内稳态平衡的破坏可以导致贫血、威尔逊疾病和门克斯疾病，并严重影响大脑的功能。近年来的研究发现，肿瘤的生长、免疫系统的功能也与铜有着密不可分的联系。本文介绍铜在人体中的生物学功能、铜蛋白的作用以及铜的运输机制及储存机制，并对铜与相关疾病的关系进行讨论。     

Cu-ZSM-5分子筛中铜的超计量交换和铜氧铜桥的形成

用离子选择性电极原位监测离子交换制备Ｃｕ－ＺＳＭ－５的过程，并用ＴＰＤ－ＭＳ研究了样品加热脱水时的变化，发现在ＰＨ值，较高的条件下铜可能多数以Ｃｕ（ＯＨ）＾＋参与交换而使Ｃｕ－ＺＳＭ－５达到所谓的超计量交换，当新鲜样品受热时，Ｃｕ（ＯＨ）＾＋会迁移到另一个Ｃｕ（ＯＨ）＾＋的近邻进行脱水而形成铜氧铜桥，此桥可进一步脱氧而使二价铜还原成一价铜，迁移，脱水形成铜氧铜桥的过程是完全可逆的。     

测定肺癌患者血清铅,锌及铜锌比值的临床意义

采用原子吸收法测定了６４例肺癌及３１例健康人的血清铅、锌含量，结果表明，肺癌组血清锌低于健康对照组，而血清铜及铜锌比值则高于对照组，差异均非常显著（Ｐ〈０．０１）。按ＴＮＭ分期，Ⅱ￣Ⅲ期肺癌组与Ⅳ期肺癌组血清锌并无差异，但前者血清铜及铜锌比值明显低于后者。若以１．５７为铜锌比值的临界值，则肺癌患者阳性符合率为５１．５６％，高于ＣＥＡ３４．３７％。但不同病理类型间血清铜锌无差异。提示铜、锌及铜锌比值     

贫血患者头发与末稍血中铁,铜含量对比研究

对两组贫血患儿用ＸＲＦ法测定头发及末稍血微量元素铁，铜含量，并与正常值做对比研究，结果显示：发铁高于正常，与血清含量降低相反，与部分研究结论相同。发铜你于正常，与血清结论相同。末销血铁，铜含量均低于正常，与血清铁，铜结论相同。末销血能否作为代表机体铁，铜含量的检验体，值得深入研究证实。     

流动注射在线分离富集光度法测定铜

本文提出痕量铜的在线流动注射离子交换树脂分离富集的吸光光度测定方法，以显色液作为淋洗液，直接洗脱Ｄ４０１螯合树脂上富集的铜，与此同时显色剂与铜（Ⅱ）生成有色络合物，在６３２ｎｍ处测定铜。     

Theoretical study of mechanism and selectivity of copper-catalyzed C-H bond amidation of indoles

Density functional theory calculations are used to study the reaction mechanism and origins of C2 selectivity in a copper(I)-catalyzed amidation of indoles. It is shown that concerted metalation-deprotonation is not able to reproduce the observed regioselectivity. Instead, an unprecedented mechanism based on a four-center reductive elimination is proposed to be responsible for the reaction outcome. This mechanism has a lower reaction barrier and is able to reproduce the experimentally observed selectivity. A possible alternative mechanism involving a Cu(II) species instead of Cu(III) is presented, but it is shown that higher energy barriers are associated with this mechanism. An important technical detail is that addition of dispersion effects to the B3LYP results is necessary to reproduce the observed selectivity, although not important for the overall mechanistic proposal.     

Effect of pretreatment of molasses and posttreatment of fermented broth in industrial production of ethanol

The aim of preclarification is to minimize sludge going to yeast separators. This purpose is partially fulfilled. However, it has been measured during the plant trial runs that preclarification does not noticeably improve fermentation. The aim of postclarification is to minimize sludge going to distillation. This purpose is well served as noted from the fact that cycle run of distillation columns using postclarification is three times longer (9–12 mo) as compared to the normal one (3–4 mo).     

Study of the influence of concentration on the time for first appearance of crystallization of polyethylene from xylene

An experiment is reported in which a simple laser light-scattering technique is used to measure the time for a critical turbidity to appear during the crystallization of polyethylene in xylene. The effect is examined over the entire range of solution concentration, and it is found that the relation between this concentration and temperature is linear for all solutions, provided that the time for turbidity to develop is arranged to be the same in all cases. In the appendix it is reasoned that similar results could have been obtained if, instead, times had been measured to a given degree of crystallinity rather than of turbidity. Departures from this linearity at low concentrations are taken as indicating multimolecular nucleation for all concentrations greater than about 1%.     

Chronocoulometric study of the electrochemistry of Prussian blue

During the electrochemical oxidation of Prussian blue (PB) to Prussian yellow (PY), an electrocatalytic oxygen production proceeds at the electrode when aqueous electrolyte solutions are used. The formed oxygen is scavenged by the PY, probably by absorption, and it is consumed during the electrochemical reduction of PY to PB by a heterogeneous chemical reaction of PB with oxygen to PY and hydrogen peroxide. Because of this catalytic regeneration of PY, it is impossible to determine the amount of low-spin iron by chronocoulometry using a potential program in which PB is first oxidized to PY and then the charge is measured to reduce PY to PB. The latter charge is biased by the electrocatalytic PY regeneration.     

Shear modulus of sintered 'house of cards'-like assemblies of crystals

A cell model of a 'house of cards'-like assembly of crystals is used for the study of the evolution of the shear modulus during sintering. The crystals are assumed to have a lozenge shape. The cell model takes different crystal-crystal contacts into account. The force needed to separate two sintered crystals is calculated using the minimum surface area (MSA) approximation. By varying the thickness, long axis, and short axis of the crystals, it is possible to make space-filing configurations which have a nonzero shear modulus at crystal volume fraction that can be as low as phi = 0.03. This is significantly lower than the volume fractions phi > 0.52 that are found in studies where the MSA approximation is applied to assemblies of spherical particles. It is found that sintering may cause a nonlinear volume fraction dependence of the shear modulus, which depends on the shape of the crystals, the type of crystal-crystal contacts, and the character of the crystal assembly. The calculated shear modulus is analyzed using the phenomenological expression (phi - phi0)beta, where phi0 represents the volume fraction at the start of sintering. The exponent beta is found to vary between 1 and 2. The interpretation of the shear modulus using a fractal model is also discussed.     

渣油悬浮床加氢水溶性催化剂预硫化研究 Ⅱ 钼酸盐硫化产物的XPS分析

通过XPS分析法对钼酸盐的硫化行为进行了考察,分别考察了四价钼物种质量分数和硫钼元素的质量分数比，发现硫化产物的表面化学组成中四价钼质量分数和硫钼元素质量分数比不成正比，证实了该产物表面钼的硫化物不完全以MoS2形式存在。未经过临氢加热的硫化产物表面的四价钼物种的质量分数显著低于经过临氢加热的样品的质量分数，说明临氢加热在钼酸盐的硫化过程中起了重要作用。氯化铵是钼酸盐硫化过程中有效的助硫化剂，当它的用量增大时，硫化产物表面四价钼的质量分数也增大。以蒽为探针，使用化学探针法测定了硫化产物在渣油加氢过程中的催化活性，发现随着氯化铵用量的增加，产物的催化活性也相应提高，印证了XPS测定结果。     

Formation of ring-shaped deposits as a result of evaporating droplets of dispersions of silver nanoparticles and study of their fine structure

Scanning electron microscopy is employed to study ring-shaped deposits formed at different time moments of evaporating droplets of silver colloidal solutions on a glass substrate. It is shown that, in addition to an external fringe, several rings are formed at intermediate stages of evaporation; these rings are, in the course of time, transformed into one dense fringe and a transition zone adjacent to its internal side. The time dependences of the height and width of the fringe are determined. It is established that an increase in the width and height of the fringe is due to the transfer of silver nanoparticles to this region, which play a key role in imparting specific structural organization to the fringe. It is noted that the height of the formed fringe may be qualitatively determined by energy dispersive X-ray microanalysis.     

Detection of cavities in a set of interpenetrating spheres

A general topological procedure is described that is able to detect cavities of all shapes and sizes in a system of interpenetrating spheres. The procedure is coupled to an analytic algorithm for computing surface areas and volumes, but as such, involves only logical operations and is therefore not subject to numerical imprecision. Its application to the identification of internal cavities in molecular systems is illustrated.     

Nonconservation of excitons as a mechanism of light-energy capturing

The analysis of nonstationary processes, taking place in exciton systems in consequence of the nonconservation of the number of elementary excitations, is presented and it is pointed out to a new possibility of light-energy capturing which exists in ecological systems due to the nonconservation of excitons. It is shown that, due to the nonconservation, the one-dimensional molecular chain is able to capture permanently the light energy of the order of 50 keV to 5 MeV. A part of the captured energy is expected to have a role in internal bioprocesses. It is also shown that the system is a seat where the processes of continuous creations and annihilations of pairs of excitons having opposite momenta take place with a probability of the order of 10^?4 to 10^?2. Further investigations would allow to identify biological phenomena caused by those processes.