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1.
SYNTHESIS AND ̄(183)W NMR CHARACTERIZATI0N OF α-[P_2W_(15)O_(62)Ti_3] ̄(12-) HFTEROPOLYANIONSYNTHESISAND ̄(183)WNMRCHARACTERIZAT...  相似文献   

2.
EXPERIMENTALSTUDIESONANEWCHEMICALOSCILLATINGREACTIONSYSTEMOFPYRUVICACID-BrO_3 ̄--H_2SO_4-[CuL] ̄(2+)¥LiangZHAO;ChangChunWU;Chua...  相似文献   

3.
双金属复合氧化物的结构与紫外阻隔性能   总被引:8,自引:1,他引:7  
双金属复合氧化物(CLDH)是一类发展迅速的无机层状材料的煅烧产物,在催化、吸附等领域已获长足进展[1],但作为紫外阻隔材料的性能研究尚鲜见报道.本文研究了不同双金属复合氧化物的紫外阻隔性能,结果发现二价金属离子为锌离子的CLDH具有良好的紫外阻隔性能.实验所用试剂均为分析纯.CLDH由NaOH,Na2CO3,MgSO4·7H2O,ZnSO4·7H2O,Al2(SO4)3·18H2O为原料,按文献[2]方法制备.ZnO+Al2O3复配物是按一定比例机械混合后,研磨,并在与CLDH相同的条件下煅烧…  相似文献   

4.
一水草酸铵(简称AOM)是一种优良的电光晶体 ̄[1]。文献 ̄[1,2]报道了该晶体的晶体结构,化学式为(NH_4)_2C_2O_2·H_2O,属正交晶系,P222空间群,晶胞参数a=0.8035nm,b=1。031nm,c=0.3801nm,z=2。本文拟报道AOM单晶生长,热化学分析,透过波段以及非线性光学性质的初步研究。  相似文献   

5.
三羰基环戊二烯基钼负离子与1,3-二卤丙烷在一缩二乙二醇二甲醚介质中反应,生成环卡宾配合物CpMoX(CO)_2CO(CH_2)_2CH2(X=Br,I).硅桥连双环戊二烯基三羰基钼负离子与1,3-二卤丙烷顺利地进行类似反应,生成相应的硅桥连双[环卡宾钼配合物]──E[C_5H_4MoX(CO)_2]CO(CH_2)_2CH_2]_2(E=Me_2Si,Me2SiSiMe_2,Me2SiOSiMe_2).化合物硅氧硅桥联二茂二钼环卡宾配合物11的晶体结构经X射线衍射测定,晶体属三斜晶系,P1空间群,晶体学数据:a=0.8188(1)nm,b=1.045(3)nm,c=2.3252(4)nm,α=94.14(2)°,β=94.09(1)°,γ=102.48(2)°,V=1.9306nm ̄3,Z=2,D_c=1.854g/cm ̄3。  相似文献   

6.
合成了稀土钨砷系列杂多化合物K_(17)[Ln(As_2W_(17)O_(61)_2]·xH_2O并经红外、极谱和 ̄(183)WNMR对其进行了表征,在[Ln(As_2W_(17)O_(61)_2] ̄17-中W原子有9种不同配位环境,Ln与8个氧原子配位。  相似文献   

7.
谢少艾 《电化学》1999,5(4):455-458
银铟硒是继铜铟硒之后新发展起来的另一种能源、信息功能材料,它的禁带宽度Eg=1.20eV,更接近于光电转换效率最高的太阳能电池所应具有的能隙值[1],因此具有广泛的应用前景.早在六十年代,前苏联就对银铟硒的物理性质及电子特性有过报道.目前有关光电化学电池(PEC)所利用的银铟硒薄膜材料的制备大多是采用大晶粒熔融生长法[2,3].80年代,RaviendraP.T.K.Sharama[4]曾报道应用电沉积法制作p_AgInSe2/CdS液结太阳能电池,但真正利用电化学沉积制备银铟硒的报道不多,由电…  相似文献   

8.
配位聚合物PAAm-CuCl_2和cuCl_2·2H_2O的Cu ̄(2+)2pXPS谱上都有Shake-up峰,其与各自的Cu ̄(2+)2p3/2肩峰或主峰距离ΔEs2或ΔEs分别为8.7和8.6eV;但配位聚合物Cu(Ⅱ)-PVA却无此峰.由此推定,前者的Cu ̄(2+)是以sp ̄3杂化轨道接受PAAm4个链节单元C-N上N的孤对电子部分转移形成配位键;而Cu(Ⅱ)-PVA配位聚合物中的Cu ̄(2+)却以dsp ̄2杂化轨道接受PVA4个链节单元侧基O的孤对电子部分转移,产生配位键,即Cu ̄(2+)与PAAm或PVA的链节单元配位比均是1:4,此结果与电导率法测定PAAm-CuCl_2的配位比相同.  相似文献   

9.
双核配合物[Cu_2(C_6H_5COO)_4(C_3H_4NS)_2]的合成与表征王冬梅,杨瑞娜,胡晓院,侯益民,薛室玉,金斗满(河南化学研究所,郑州450003)关于双核铜(II)配合物的合成,曾有不少文献报道 ̄[1-4]。但这些合成大都是利用铜...  相似文献   

10.
詹梦雄  余荣清 《电化学》1995,1(3):362-365
C_(60)球烯是具有高度对称性的全碳原子簇,它既是电子受体,又是电子给体,表现出特有的光物理与光化学性能 ̄[1,2].近十多年来众多的研究者对具有电子给体和电子受体的共轭π电子体系化合物在光照下的行为进行了深入研究 ̄[3],认为用它作为有机光电子功能材料具有十分广阔的前景。随着人们对球烯研究的不断深入,尤其是宏观量球烯的合成与分离已日趋完善,以球烯为基础的有机光电材料必将越来越受到重视.金属酞青化合物由于拥有众多π电子的共轭体系,具有良好的光敏、半导体等性能,是较好的有机光电材料 ̄[4.5].但在可见光区,其光敏性仍不够强,本文以ZnPc掺杂C_(60)探索其光电性能,以期提高其光敏性.同类研究尚未见文献报道.  相似文献   

11.
固态电池发展至今,许多比能量高、贮存性能好的新型电池产品不断涌向市场,而目前广泛用于正极材料的大多数物质是层状化合物[1],如聚乙炔,聚苯胺等化合物,它们贮存能量的方式主要是通过插入化学反应来实现,本工作将合成一种高分子材料——2.5-二巯基-1,3...  相似文献   

12.
锂-空气电池是目前已知具有最高能量密度的二次电池,有望成为未来电动汽车的动力电源。由于其能量密度高、环境友好以及成本较低,成为广大科研工作者研究的热点,在过去二十年间与之有关的研究已经在反应机理、电极结构、催化剂及电解液等各方面都取得了很大进展,但受诸多因素限制,其实用化仍然任重道远。本文总结了近几年来非水体系锂-空气电池在反应机理、正极材料、催化剂、电解液以及锂负极等方面的最新研究进展,并在此基础上展望其未来的发展方向。  相似文献   

13.
锂离子电池是目前广泛应用的高能量密度小型二次电池,但随着其应用领域突飞猛进的发展,迫切需要进一步提高其能量密度.本文介绍了近年来高能量密度锂离子电池正、负极材料及新型高能量密度锂二次电池体系方面的研究进展;结合本实验室的研究工作,着重介绍了高容量正、负极材料的选择、微纳结构设计、表面包覆和合成策略;讨论了锂硫电池、锂空气电池等高比能金属锂二次电池的未来发展方向.  相似文献   

14.
Lithium heteropoly blue(Li5PW10^ⅥW2^ⅤO40)was used as a non-aqueous electrolyte in the polyacenic semiconductor(PAS)-Li secondary battery instead of LiClO4.The properties of the PAS-Li secondary battery,especially the effect of Li5PW10ⅥW2^ⅤO40 on the capacity,the cycle property and the self-discharging of the battery have been investigated.The results indicate that not only i5PW10ⅥW2^ⅤO40 can overcome the disadvantages of LiClO4,which is apt to explode when heated or rammed.but also the PAS-Li secondary battery assembled with the novel electrolyte has a larger capacity and smaller self-discharging than that assembled with LiClO4.Therefore,it is believed that lithium heteropoly blue is a better and novel electrolyte for the PAS secondary battery and exhibity significant and practical application.  相似文献   

15.
Electrolyte is essentially important for electrochemical and safety performance of batteries. The pseudoconcentrated electrolyte, with lean solvent but anion-involved solvation sheath and heterogeneous long-range structure, endows the electrolyte with superior interfacial properties and the bulk properties, enabling the high-voltage lithium-ion battery, lithium-metal battery, and sodium battery with outstanding electrochemical performances. Nonflammable solvents as diluent in the pseudoconcentrated electrolyte can reach 30–60% by volume share, making the electrolyte nonflammable and then showing great possibility in mitigating the thermal runaway of the battery. As a new family of liquid electrolyte, nonflammable pseudoconcentrated electrolyte is promising for high safety and high energy density secondary batteries.  相似文献   

16.
A novel redox flow battery–single flow Zn/NiOOH battery is proposed. The electrolyte of this battery for both negative electrode and positive electrode is high concentration solutions of ZnO in aqueous KOH, the negative electrode is inert metal such as nickel foil, and the positive electrode is nickel oxide for secondary alkaline batteries. Typically, there is no requirement for a membrane in the battery. Ni(OH)2 is oxidized to NiOOH at positive electrode and the zincate ions is reduced to zinc and electroplated onto the negative electrode during charge. The reverse occurs during discharge. Results obtained with a small laboratory cell show that high efficiencies can be achieved with an average coulombic efficiency of 96% and energy efficiency of 86% over 1000 cycles. High performance obtained indicates that the single flow zinc/nickel battery is a promising battery.  相似文献   

17.
Lithium metal batteries have achieved large-scale application, but still have limitations such as poor safety performance and high cost, and limited lithium resources limit the production of lithium batteries. The construction of these devices is also hampered by limited lithium supplies. Therefore, it is particularly important to find alternative metals for lithium replacement. Sodium has the properties of rich in content, low cost and ability to provide high voltage, which makes it an ideal substitute for lithium. Sulfur-based materials have attributes of high energy density, high theoretical specific capacity and are easily oxidized. They may be used as cathodes matched with sodium anodes to form a sodium-sulfur battery. Traditional sodium-sulfur batteries are used at a temperature of about 300 °C. In order to solve problems associated with flammability, explosiveness and energy loss caused by high-temperature use conditions, most research is now focused on the development of room temperature sodium-sulfur batteries. Regardless of safety performance or energy storage performance, room temperature sodium-sulfur batteries have great potential as next-generation secondary batteries. This article summarizes the working principle and existing problems for room temperature sodium-sulfur battery, and summarizes the methods necessary to solve key scientific problems to improve the comprehensive energy storage performance of sodium-sulfur battery from four aspects: cathode, anode, electrolyte and separator.  相似文献   

18.
聚吡咯以其制备简单、掺杂可逆、环境友好、导电率高、比电容大、具有良好的成膜性而备受关注。特别是在作为超级电容器、二次电池等换能设备电极材料领域中前景广阔。文章简略地介绍了超级电容器的双电层电容和法拉第赝电容产生的机理,概述了近年来聚吡咯与金属氧化物、炭材料等通过化学法、电化学法以及界面化学法等新型手段制备聚吡咯电极的研究进展。  相似文献   

19.
Flexible lithium/sulfur (Li/S) batteries are promising to meet the emerging power demand for flexible electronic devices. The key challenge for a flexible Li/S battery is to design a cathode with excellent electrochemical performance and mechanical flexibility. In this work, a flexible strap-like Li/S battery based on a S@carbon nanotube/Pt@carbon nanotube hybrid film cathode was designed. It delivers a specific capacity of 1145 mAh g−1 at the first cycle and retains a specific capacity of 822 mAh g−1 after 100 cycles. Moreover, the flexible Li/S battery retains stabile specific capacity and Coulombic efficiency even under severe bending conditions. As a demonstration of practical applications, an LED array is shown stably powered by the flexible Li/S battery under flattened and bent states. We also use the strap-like flexible Li/S battery as a real strap for a watch, which at the same time provides a reliable power supply to the watch.  相似文献   

20.
Direct fluorination of 1,3-dioxolan-2-one with elemental fluorine was successfully carried out to provide 4-fluoro-1,3-dioxolan-2-one, which was expected as an additive for lithium ion secondary battery. 4-Fluoro-1,3-dioxolan-2-one was also further fluorinated with elemental fluorine to give three isomers of difluoro derivatives by the same methodology. Another topic is the preparation of trifluoromethanesulfonyl fluoride, an intermediate of lithium battery electrolyte, by the reaction of methanesulfonyl fluoride with elemental fluorine. The use of perfluoro-2-methylpentane as a solvent gave satisfactory selectivity of trifluoromethanesulfonyl fluoride.  相似文献   

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