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1.
以氯甲基杂环聚醚酮(CMPPEK)为原料,加入三乙胺进行铵化,并分别加入二乙烯三胺(DETA)和二乙胺(DEA),生成的仲胺基(或叔胺基)与邻近分子链氯甲基团进行自交联.经过制膜和离子交换反应,制备了DETA自交联杂萘联苯聚芳醚阴离子交换膜(DETA-QPPEK-OH)和DEA自交联杂萘联苯聚芳醚阴离子交换膜(DEA-QPPEK-OH).采用傅里叶变换红外(FTIR)光谱对制备自交联膜的化学结构进行表征.研究了DETA-QPPEK-OH和DEA-QPPEK-OH膜的理化性质,结果表明前者具有较低吸水率和更低溶胀度.通过研究DETAQPPEK-OH和DEA-QPPEK-OH膜的离子传导率随温度的变化规律,结果表明在80°C时其离子传导率分别达到0.060和0.028 S cm-1,表明本文制备的自交联膜具有较高离子传导率.此外还通过热重分析(TGA)对两类自交联膜的热稳定性进行了研究.  相似文献   
2.
通过较简单的方法合成了纤维素二乙烯三胺负载钯(0)配合物,并利用XPS、TG、DTA等手段对其进行了表征。该配合物在室温至230℃范围内有很好的稳定性,在空气氛围、DMSO中能有效地催化丙烯酸、苯乙烯与芳基碘的Heck反应,立体选择性地生成取代的反式肉桂酸、1,2-二苯乙烯,在70℃时反应6h,产率≥66%(丙烯酸、苯乙烯与带取代基芳基碘的Heck反应产率接近100%)。催化剂中起催化作用的是金属态的钯。  相似文献   
3.
In this study we introduced dialdehyde groups to a commercial regenerated cellulose (RC) ultrafiltration membrane by periodate oxidation. They were further converted to nitrogen-containing derivatives by Schiff base reaction with diethylenetriamine (DETA). The modified membrane was challenged with aqueous solution containing Pb(II) metal ions. The different variables affecting the rejection of lead ion by membrane including oxidization time, concentration of DETA, initial metal ion concentration and pH of the solution were elucidated. The membranes were characterized by FTIR-ATR, SEM, EDAX and elemental analyses. The process efficiency was enhanced by improving the oxidization time up to a certain period. In our case this was diminished after 9 h due to deterioration in the membrane integrity. The Pb2+ removal was facilitated by increasing feed pH and DETA concentration. This was diminished for more concentrated metal ion in the feed. Membrane regeneration was successfully utilized using 0.1 M HNO3 solution. The removal capability of the regenerated membranes was maintained even after four cycles.  相似文献   
4.
Acyclic N,N′-(poly)ethylene-bis(2-arylazo-1,3-aminovinylketones) are the main products in the reactions of fluoroalkyl-containing 2-arylhydrazono-1,3-diketones with ethylenediamine, diethylenetriamine and triethylenetetramine. Nickel(II) and copper(II) chelates were obtained from N,N′-ethylene-bis(2-arylazo-1,3-aminovinylketones). 2-Arylhydrazono-3-fluoroacyl esters formed N,N′-ethylenediamides of 2-arylhydrazono-3-fluoroacylpropionic acids with ethylenediamine. Interaction of 2-arylhydrazono-3-fluoroacyl esters with diethylenetriamine and triethylenetetramine resulted in and decomposition products.  相似文献   
5.
The syntheses and crystal structures of four new divalent transition metal complexes of the types [Cu2(dien)2(nic)](ClO4)3 · MeOH (nic = anion of nicotinic acid; dien = diethylenetriamine), 1; [Cu(dien)(nic)]2(nic)2, 2; [Cu(dien)(nic)]2(BF4)2 · 2MeOH, 3 and [Ni(dien)(nic)(H2O)]4(NO3)4 · 2MeOH, 4, are reported, which were prepared by the reactions of diethylenetriamine and nicotinic acid with Cu(ClO4)2 · 6H2O, Cu(OAc)2 · H2O, Cu(BF4)2 · 6H2O and Ni(NO3)2 · 6H2O in MeOH, respectively. These complexes were characterized by single-crystal X-ray diffraction method and elemental analyses. In the cation of complex 1, one nicotinate ligand bridges two Cu(II) metal centers through the pyridyl nitrogen atom and one of the carboxylate oxygen atoms. The cations of complexes 2 and 3 form the twelve-membered metallocycles, involving two Cu(II) ions that are bridged by two nicotinate ligands. The cation of complex 4 forms a tetranuclear cage with the four Ni(II) metal centers bridged by four nicotinate ligands and each Ni(II) metal center adopts the distorted octahedral geometry. Their thermal properties have been investigated by using differential scanning calorimetry (DSC) and thermogravimetric analyses (TGA).  相似文献   
6.
近年来,化石燃料燃烧导致的环境污染问题和能源危机越来越严重.在众多解决方案中,光催化产氢由于其可持续性以及无污染等特点而受到广泛关注.然而,由于许多半导体光催化剂性能不理想,光催化水分解研究进程缓慢.本研究采用水热法成功制备了梯型Pg-C3N4/Zn0.2Cd0.8S-DETA复合材料用于光催化产氢.DETA(二亚乙基三胺)作为一种有机分子插入在Zn0.2Cd0.8S的层中构成有机-无机杂化材料.采用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外-可见光漫反射光谱(UV-vis)以及光电流研究了所制备样品的结构、形貌、元素组成以及光电特征,并提出了可能的光催化机制.XRD和XPS结果表明Pg-C3N4和Zn0.2Cd0.8S-DETA复合在一起而不是机械混合.通过TEM可以看出Pg-C3N4是一种带有很多孔洞的纳米片,而Zn0.2Cd0.8S-DETA类似于纳米花瓣,在Pg-C3N4/Zn0.2Cd0.8S-DETA复合材料中Pg-C3N4表面充满了Zn0.2Cd0.8S-DETA纳米花瓣.经过元素分析得知所合成的复合材料没有杂质元素.UV-vis表明Pg-C3N4和Zn0.2Cd0.8S-DETA具有良好的吸收带边以及带隙,分别为2.83 eV和2.48 eV.光电流和PL显示15%Pg-C3N4/Zn0.2Cd0.8S-DETA具有很高的载流子分离及传输效率.光催化性能测试显示15%Pg-C3N4/Zn0.2Cd0.8S-DETA具有很好的产氢活性,为6.69 mmol g^-1 h^-1,分别是Pg-C3N4和Zn0.2Cd0.8S-DETA的16.73和1.44倍.在经过七次循环实验后15%Pg-C3N4/Zn0.2Cd0.8S-DETA仍保持很优异的活性,说明它具有很好的稳定性.通过高分辨XPS中各元素结合能的变化可以看出构成异质结之后电子的流向,从而看出光催化可能的机制为梯形.光照射之后,Pg-C3N4和Zn0.2Cd0.8S-DETA中产生电子-空穴对,电子迁移到导带并在价带留下空穴.当Pg-C3N4与Zn0.2Cd0.8S-DETA复合之后,在它们的接触处会形成内部电场,Zn0.2Cd0.8S-DETA导带上的电子和Pg-C3N4价带上的空穴会在内部电场作用下复合.Zn0.2Cd0.8S-DETA价带上的空穴和Pg-C3N4上的电子分别参与氧化还原反应.梯形机制促使电子和空穴在空间上分离,从而具有强氧化还原性.梯形异质结的形成加快了15%Pg-C3N4/Zn0.2Cd0.8S-DETA复合材料中电子-空穴对的分离效率,并减少了电子-空穴对的复合,从而使其具有很优异的光催化性能和稳定性.  相似文献   
7.
Two cyano-bridged copper(II)–copper(I) mixed-valence assemblies, Cu(EAM)2[Cu(CN)2]2 1 (EAM?=?ethanolamine) and Cu(DETA)[Cu(CN)2]2·0.5H2O 2 (DETA?=?diethylenetriamine), have been prepared and structurally and magnetically characterized. IR spectra indicate the presence of bridging cyano groups in both 1 and 2, confirmed by structure analyses; Cu(I)–CN–Cu(II), Cu(I)–CN–Cu(I) and Cu(I)–Cu(I) metal bond linkages are evident. In the lattice, a 3D network is formed by two [Cu(CN)2]?? units and one [Cu(EAM)2]2+unit for 1. Variable temperature magnetic susceptibilities, measured in the 5–300?K range, indicate weak antiferromagnetic exchange interactions in complex 1.  相似文献   
8.
Four kinds of silica-gel supported diethylenetriamine adsorbents with different structures, were prepared by so-called “heterogeneous-direct-amination” (hetero-DA), “homogeneous-direct-amination” (homo-DA), “heterogeneous end-group protection” (hetero-EGP), and “homogeneous end-group protection” (homo-EGP) methods, respectively. The obtained products were named SG-HE-dD, SG-HO-dD, SG-HE-pD and SG-HO-pD, respectively (where SG means silica-gel; HE means heterogeneous, HO means homogeneous, d means direct, p means protected and D means diethylenetriamine). Their structures were characterized by FT-IR, elemental analysis, porous structure analysis and thermogravimetric analysis. The adsorption capabilities of such adsorbents towards Hg(II) were studied and evaluated by static method. SG-HE-pD and SG-HO-pD showed higher performance towards Hg(II) adsorption than corresponding counterparts SG-HE-dD and SG-HO-dD, even though the former two possessed lower contents of diethylenetriamine (DETA). The kinetics data indicated that the adsorption process was governed by the film diffusion and followed pseudo-first-order rate model for SG-HE-dD, SG-HO-dD and SG-HE-pD and pseudo-second-order model for SG-HO-pD. The Langmuir model was applied to fit the experimental equilibrium data for all adsorbents. The end-group protection method exhibited its advantage in preparation of effective adsorbent for metal ions uptake compared to the direct-amination method.  相似文献   
9.
采用二乙烯三胺(DETA)与聚丙二醇二缩水甘油醚(PPGDGE)反应合成出DETA-PPGDGE-DETA型的多元胺加成物,然后再用一定比例环氧树脂E-20封端加成,制备出了水性环氧树脂固化剂。红外光谱(IR)及飞行时间质谱(TOF-MS)验证了该水性环氧固化剂的结构。考察了不同反应条件对固化剂结构与性能的影响,结果表明,二乙烯三胺/聚丙二醇二缩水甘油醚环氧基物质的量比为10∶1,用沸点稍高的二乙二醇丁醚(DGBE)将体系中残留小分子DETA蒸除干净,环氧树脂E-20封端20%伯胺氢时,固化剂与环氧乳液混合后的涂膜性能最佳。  相似文献   
10.
氮掺杂碳纳米管的制备及其电化学性能   总被引:2,自引:0,他引:2  
采用弱反应性含氮有机物水合肼、二乙烯三胺对碳纳米管进行氮掺杂处理. 结合X射线光电子谱(XPS)分析和扫描电镜(SEM)观察, 发现两种含氮有机物处理均可使碳纳米管表面成功连接上含氮基团, 并保持了碳纳米管的本征形貌和结构. 水合肼处理的碳纳米管的氮含量(碳/氮原子比为95/2)明显高于二乙烯三胺处理的碳纳米管(碳/氮原子比为96/0.5). 氮掺杂后碳纳米管在水溶液中分散性明显改善, 且分散性随着氮含量增加进一步增强, 因此水合肼处理的碳纳米管分散性明显优于二乙烯三胺处理的碳纳米管. 作为电化学电容器电极材料, 碳纳米管含氮官能团贡献了赝电容, 但其循环性仍需进一步改进. 氮掺杂碳纳米管较好的亲水性, 改善了电解液的浸润, 循环后氮掺杂碳纳米管电极的比容量仍略高于纯碳纳米管电极的比容量.  相似文献   
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