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81.
A novel coordination polymer {[Zn(ts-gln)(bipy)]3H2O}n (ts-glnH2=N-p-toly-sulfonyl-glutamine,bipy=2,2-bipyridine) has been prepared and structurally characterized by X-ray diffraction method. It crystallizes in orthorhombic,space group P212121 with a=8.2622(5),b=16.6244(10),c=18.2807(10) ,V=2510.9(3) 3,C22H28N4O8SZn,Mr=573.91,Z=4,Dc= 1.518 g/cm3,μ(MoKa)=1.115 mm-1,F(000)=1192,the final R=0.0262 and wR=0.0662 for 5691 independent reflections with Rint=0.0240. The zinc(Ⅱ) atom is coordinated by N(3) and N(4) atoms of a bipy molecule,two carboxylate O(1) and O(2A) and amino N(1) atoms of ts-gln ligands,resulting in a square-pyramidal geometry. The title complex consists of an infinite zigzag chain of zinc(Ⅱ) ions linked by the carboxylate of N-p-tolysulfonyl-glutamine.  相似文献   
82.
三芳基膦配体的合成研究   总被引:1,自引:0,他引:1  
从间溴苯酚出发, 利用新的合成方法经五步反应合成了一系列具有不同烷氧基的芳基膦配体. 改进后的方法可方便地通用于在苯环上具有各种不同基团基的膦配体衍生物的合成, 且有原料易得、操作简单、产率较高的优点.  相似文献   
83.
陈凯  马宏佳  刘光祥 《化学教育》2019,40(14):53-60
为深入了解地方性师范院校化学师范生知识建构习惯和水平,探讨他们在大学专业基础课程中的学习历程,以物理化学课程中以“融合科学读写特色”的“热化学”学案作为研究载体,研究对象在学案引导下开展自学活动,并在阅读教材和文献基础上进行科学写作。采用量表工具针对大学生自学效果和反思活动进行评价,并采用SOLO分类评价科学写作作品,采用KWL工具评价学生的科学阅读收获。结果发现研究对象学习动机不强,不擅长在新的学科知识学习中联系已有专业课程知识,基于文本学习的建构活动水平极低,可能是因为他们在应试背景下的基础知识并未形成体系,先修课程中并未培养元认知学习策略。  相似文献   
84.
High-energy-density batteries are in urgent need to solve the ever-increasing energy storage demand for portable electronic devices, electric vehicles, and renewable solar and wind energy systems. Alkali metals, typically lithium(Li), sodium(Na) and potassium(K), are considered as the promising anode materials owing to their low electrochemical potential, low density, and high theoretical gravimetric capacities. However, the problem of dendrite growth of alkali metals during their plating/stripping process will lead to low Coulombic efficiencies, a short lifespan and huge volume expansion, eventually hindering their practical commercialization. To resolve this issue, a very effective approach is engineering the anodes on structured current collectors. This review summarizes the development of the alkali metal batteries and discusses the recent advances in rational design of anode current collectors. First, the challenges and strategies of suppressing alkali-metal dendrite growth are presented. Then the special attention is paid to the novel current collector design for dendrite-free alkali metal anodes. Finally, we give conclusions and perspective on the current challenges and future research directions toward advanced anode current collectors for alkali metal batteries.  相似文献   
85.
Wei  Xiang  CHEN  Xiao  Chun  MA 《中国化学快报》2003,14(3):312-315
Non-carbon inorganic fullerene-like(IF) nanoscale materials have recently attracted intense interest due to their nested hollow and nanotube structures,In this letter,IF-WS2 nanoparticles prepared by solid-gas reaction were characterized by X-ray diffraction,Scanning electron microscopy and transmission electron microscopy.The results show that the IF-WS2 nanoparticles have a nested hollow closed spherical structure with diameter of 100-150mm.  相似文献   
86.
Propargylic alcohols are versatile precursors to many organic molecules including natural products and pharmaceutical compounds.[1] In our continuing interest in the development of practical methods for synthesis of ferrocene derivatives, we decided to investigate the efficiencies of ferrocenylacetylene addition to aromatic aldehydes under t-BuOKcatalyzed condition.[2] Interestingly, we found that the usually reliable coupling reaction between terminal alkyne of type 1 and aromatic aldehydes of type 2 does not furnish the expected propargylic alcohols, but that the isomeric aryl enones 3are found in high yield and very short reaction time (10~20 min). This provided a promising protocol for preparation of ferrocenyl chalcones in a practical, economical and mild sense compared with the traditional method. To the best of our knowledge, this unusual reaction was first observed for the addition of ferrocenylacetylene to aldehyde in a base-catalyzed manner (Eq. 1).  相似文献   
87.
A new approach to synthesis of 6,7-dimethoxyisatin is reported.2-nitro-3,4-dimethoxy mandelonitrile in glacial acetic acid was treated with the solution of stannous chloride in hydrochloric acid to give 6,7-dimethoxyisatin in a high yield.  相似文献   
88.
IntroductionOrganotincarboxylatesarewidelyusedasbiocides ,fungicideandashomogeneouscatalystsinindustry .1 6Inordertoexploretherelationshipsbetweenbiologicalactiv ityandstructure ,anumberofsuchmoleculeshavebeensynthesizedandstudiedinrecentyears .7 15Studieson…  相似文献   
89.
Oxidation of alcohols to the corresponding aldehydes or ketones is one of the most fundamental reactions in organic chemistry [1,2]. Some of the products of the oxidation exhibit an important role in the organic synthesis as well as pharmaceutical synthesis. In most reactions, the lanthanide complexes show satisfied catalytic activities for some compounds. Furthermore, there has been increasing interest in the lanthanide complexes and several reports have appeared in the literature [3, 4]. But the exploitation of these complexes for the oxidation of some organic substrates has been limited. Here we reported a method for the preparation and the catalytic properties as well as the recycling of lanthanide complexes in oxidation of alcohols.The synthetic procedure for the polymer supported lanthanide complexes is shown as following(scheme 1):●-NH2+CICH2COOH(C2Hs)3N→●-NHCH2COOHM=Ce(Ⅲ), Tb(Ⅲ), Sm(Ⅲ)scheme 1The oxidation of benzyl alcohol was carried out in the presence of iodosylbenzene by the polymer supported Ce(Ⅲ), Tb(Ⅲ) and Sm(Ⅲ) catalysts at 80℃ for 4.0h, the yields of benz-aldehyde are as following (table 1):Table 1 Oxidation of benzyl alcohol with the supported catalysts**Reaction condition: benzyl alcohol 0.1 mmol, iodosylbenzene 0.15mmol,catalyst 0.2mg, 80℃ for 4.0h in 1,2-dichloroethane.It can be seen from the table that the Tb(Ⅲ) complex shows higher catalytic activity for the oxidation of benzyl alcohol. Further investigation is now being carded on to optimize the results.  相似文献   
90.
The effects of alkali metals (Na+,K+) on the exchange degree of Hβ zeolite under different conditions and the conversion of α(or β)-methylnaphthalene over the alkalized zeolites were studied. The results showed that the H+ of Hβ zeolite is totally replaced by the Na+ of NaCl solution, while partially exchanged by the K+ of KC1 solution, there is an exchange equilibrium between the H+ and K+ for Hβ zeolite (Si/Al=17.23) and the value of equilibrium is 88.39. The exchange degree also increases with increasing the Si/Al of the samples. It was suggested that these resluts are attributed to the electrostatic field in the pore of Hβ zeolite and the nature of zeolite and the properties of alkali metal. The isomerization of α(or β)-methylnaphthalene is the main reaction over the samples and it is more favour on the proper acid-base sites of KHβ zeolite.  相似文献   
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