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1.
在双组分或多组分有机共晶中,特殊的分子堆积方式和聚集态结构以及不同组分之间的协同和集合效应,使得有机共晶不仅保留了单一组分的固有属性,而且展现出更多新颖的宏观光电性质,在电导、铁电、双极性电荷传输、光响应、发光和给受体组分间电荷转移过程等方面具有重要的研究价值和应用前景,为有机单晶器件的高性能化和多功能化发展提供了新途径。因此,有机共晶的制备和性能研究逐渐成为近年来的热点。在本文中我们首先详细地介绍了有机共晶的分类情况,根据形成晶体的作用力分为电荷转移晶体、通过π-π相互作用形成的晶体和以分子间氢键、卤键相互作用为主的晶体;其次,以经典的7,7,8,8-四氰基对苯二醌二甲烷(TCNQ)、1,2,4,5-苯四甲腈(TCNB)和富勒烯(C60)三种典型的受体分子为例,列举了常见的有机给受体材料;再次,介绍了8种制备有机共晶的常用方法,讨论了有机共晶中分子排布方式对性能的影响;最后,介绍了有机共晶在光电器件中的应用。我们相信有机共晶的理论和应用研究会进一步丰富和推动有机晶体材料和光电子学领域的发展。  相似文献   

2.
共晶含能材料研究进展   总被引:1,自引:0,他引:1  
共晶是不同种类的分子(两种或两种以上)通过氢键等分子间相互作用,形成具有特定结构和性能的多组分分子晶体,不同含能材料形成共晶可以有效改善炸药的感度、安全性等性能。针对目前高能炸药的改性需求,共晶在含能材料领域中的应用具有巨大的潜力。综述了共晶的形成原理及生长特性,总结了常见共晶的制备方法和表征方法,评述了含能材料共晶的研究现状和发展前景。  相似文献   

3.
盐酸氨基脲的二阶非线性光学性质研究   总被引:2,自引:0,他引:2  
非线性光学(NLO)材料在光学信息处理、远程通讯等光电子学领域有着重要的应用,有效地预测和设计出二阶非线性光学材料所必需的非中心对称晶体,提高材料的综合性能是这一领域的研究热点。标题化合物盐酸氨基脲是以尿素为分子母体的有机离子型化合物,具有将有机和无机材料的优异性能集于一身的结构优势,是综合性能优的材料之一。  相似文献   

4.
60富勒烯及其衍生物因其结构的特殊性,在有机超导、分子磁性、有机发光材料、分子器件、非线性光学活性、能量代谢和生物活性等[1]方面表现出独特的性能和潜在的应用前景,是非常活跃的研究领域之一.  相似文献   

5.
二阶非线性光学(NLO)材料又称为倍频材料,在光电子学领域中具有广泛的应用,是近年来研究热点之一[1~4].与无机材料相比,由于有机倍频材料具有非线性光学系数大、响应时间短和抗光伤阈值高等优异性能而倍受人们的关注.但有机材料在透光性能、热稳定性和材料的可加工性方面不及无机材料,使之应用受到很大限制.因而有效地解决这一问题是其得以广泛应用的关键.对于有机倍频材料来说,优化材料综合性能的关键在于保持有机材料优良性能的基础上提高化合物的透光性和热稳定性.有机化合物的分子间氢键和两性离子对改善NLO材料的热稳定性和牢固性…  相似文献   

6.
微纳激光器是一类尺寸或模式体积在波长或亚波长尺度的小型化激光器,由于其在超灵敏化学、生物传感和片上光信息的产生、传输、处理等领域具有重要应用而备受关注.有机材料来源广泛、吸收与发射截面大,有利于产生高的光学增益,为构筑低阈值激光器提供了条件;其丰富的激发态过程为激光性能的调控提供了便利.有机材料具有良好的柔性和加工性能,可以通过自组装、3D打印、喷墨打印等多种方法制备得到高品质的光学微腔.因此,有机材料极有希望成为下一代微纳激光器的理想选择.本文从光学微腔和增益介质两方面概述了有机微纳激光器的研究进展,着重介绍了通过微腔结构和有机材料的激发态过程来调控激光性能的一系列方法,介绍了具有特定功能的复合结构有机微纳激光器的设计和构筑策略,总结了有机微纳激光在化学、生物传感和光学集成等领域的应用进展,并对其未来的发展方向和研究思路进行了展望.  相似文献   

7.
信息动态     
有机光电功能材料作为一种新型功能材料,已应用于高科技领域和民用领域,故借2016年11月召开“2016年国际光致变色会议”之机出版主题专辑,内容主要涉及光致变色和荧光探针领域,希望可以为相关领域的研究人员提供一个展示成果的平台,推动包括光致变色等有机光电功能材料研究工作的深入开展. 此次国际光致变色会议主题之一的有机光致变色材料是光化学研究的重要内容之一,其种类繁多,反应机理也不尽相同,如何根据光物理和光化学原理设计出新型低背景颜色、抗疲劳性强、易于调控的分子,是有机光致变色材料研究的基础.本专辑中的综述文章介绍了不同体系的光致变色材料,包括萘并吡喃光致变色荧光体系(东北师范大学王广等)和二芳烯类光致变色体系(南昌大学蒲守智等)在分子开关器件的应用,还介绍了有机分子三重激发态的调控与应用(大连理工大学赵建章等),并特别感谢赵建章老师精心设计了专刊封面.这些光致变色体系和发光体系都是近年来国内外研究的重点工作.  相似文献   

8.
共晶工程作为化学材料的重要研究手段之一,在光电学、药学等多个领域取得了不同的研究进展与成果。与传统合成方法相比,共晶可通过简便、低成本的操作实现共晶组件的多功能性,同时通过微观调控实现共晶形态、结构乃至颜色的调节。本综述首先介绍了共晶的分类和制备,然后介绍了有机电荷转移共晶发光材料、机械变色发光材料的荧光颜色调控以及药物共晶、有机光电功能共晶的颜色调控;其次,介绍了外部内部因素对晶体形态调控的影响;最后,介绍了共晶晶体多态性和荧光色彩之间的关系以及共晶材料的未来发展。希望本文可以为共晶材料颜色和形态方面的优化与改善提供一定的思路,也为其他化学材料的质量优化提供借鉴意义。  相似文献   

9.
《高分子学报》2017,(2):155-177
树状分子是指一类结构高度支化的大分子或高分子化合物,其独特的三维纳米球形结构、分子内空腔以及大量富集的表面基团,可产生诸多特殊且有趣的功能及光物理性质,在化学、生物和材料等领域获得了广泛的关注和研究.本文主要综述了我们课题组在具有枝状结构二阶非线性光学高分子方面的研究进展,重点介绍了如何通过合理分子设计,发展不同类型枝状拓扑结构以有效提高材料的综合性能,并展望了该领域的今后发展趋势.  相似文献   

10.
聚合物非线性光学材料   总被引:3,自引:0,他引:3  
最近,有机非线性光学材料已引起了人们极大的兴趣。一些可极化有机分子具有很大的分子超极化率,可惜,受晶体对称性的限制仅有少数晶体具有二阶非线性光学效应。极化聚合物可以产生统计非中心对称的环境,使材料的二阶特性显示出来。本文在简单介绍了有机非线性光学和极化的原理后,综述了聚合物二阶非线性光学材料的研究进展。此外,对聚合物的三阶非线性光学效应的研究也作了介绍。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

14.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

15.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

16.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

17.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

18.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

19.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

20.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

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