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1.
在阐述了萘酞菁配合物的结构特点和气敏机理的基础上,讨论了影响萘酞菁配合物气敏性的主要因素,介绍了近年来萘酞菁配合物气敏物特性研究的最新进展,并对萘酞菁配合物作为气敏材料的发展趋势进行了展望。  相似文献   

2.
高灵敏度高选择性气敏材料--金属酞菁配合物   总被引:1,自引:0,他引:1  
酞菁配合物是一类重要的光电功能材料.由于它的特殊结构使其成为高灵敏度高选择性气敏材料,具有极好的应用前景.本文在介绍酞菁配合物的结构特点、合成方法、气敏特性及其最新研究进展的基础上,讨论了酞菁配合物的气敏机理及膜结构、中心金属和取代基对气敏性的影响,并对酞菁配合物作为气敏材料的发展趋势进行了展望。  相似文献   

3.
综述了酞菁类化合物LB膜的导电性、气敏性、气敏的检测,以及气敏机理和动力学机制。  相似文献   

4.
八—4—(四氢糠氧基)双酞菁衍生物钕(Ⅲ)、铕(Ⅲ)的合成和LB膜的气敏性张引*辛春梅王丹(吉林省教育学院化学系,长春130022)梁冰洁**陈文启席时权(中科院长春应用化学研究所,长春130022)关键词:希土双酞菁衍生物LB膜气敏性荧光性紫外可见...  相似文献   

5.
在三-(2,4-二特戊基苯氧基)-一-(8-喹啉氧基)酞菁铜中掺杂SnO2超微粒子复合成膜,发现SnO2与酞菁铜分子之间有一定的相互作用,对酞菁铜分子的结构有一定的破坏;气敏性研究表明掺杂后导电率提高一个数量级,稳定性提高。  相似文献   

6.
酞菁化合物有序聚集体已成为材料化学中的研究热点[1,2],在酞菁分子中引入冠醚会大大改善酞菁化合物的气敏性,在提高响应速度和重复性的同时,其响应温度可降到室温[3,4].研究冠醚酞菁气敏性质的通常方法是将其制成浇铸膜[4],这种膜是无序的.膜中分子的...  相似文献   

7.
四-4-(烷氧基-羰基)酞菁铜(Ⅱ)的合成、结构及其成膜性   总被引:2,自引:0,他引:2  
本文合成了两种新型取代酞菁铜(Ⅱ)配合物:四-4-(戊氧基-羰基)酞菁铜(Ⅱ)(A)和四-4-(癸氧基-羰基)酞菁铜(Ⅱ)(B),并通过元素分析、ESR、~1H-NMR和FT-IR进行了表征.用可见光谱研究了它们在氯仿溶液中的聚集形式;用X-ray粉末衍射方法研究了配合物的固相堆积排列结构.两种配合物的氯仿溶液在亚相(水)上的π-A曲线表明,它们均有明显的“气”“液”“固”变化过程;并能在不同的表面压力区间形成较好的单分子层和多分子层膜.  相似文献   

8.
油溶非对称取代酞菁铜的合成、表征及LB膜   总被引:1,自引:0,他引:1  
本文以邻苯二甲酰亚胺为原料,合成了两种新的非对称取代酞菁铜配合物:4-(对羧基苯氧基)-三-4-(2,4-二特戊基苯氧基)酞菁铜(Ⅳ)和4-(邻氨基苯氧基)-三-4-(2,4-二特戊基苯氧基)酞菁铜(Ⅴ)。并经元素分析、红外光谱、核磁共振谱、质谱、顺磁共振谱及紫外光谱,对其结构进行了表征。两种配合物都易溶于二氯甲烷、氯仿和甲苯等有机溶剂,不溶于水。配合物的氯仿溶液能在水面上展开形成单分子膜。π-A曲线测定表明,配合物在亚相液面(水)上,随着表面压力的增大,膜面积连续不停地减少,有明显的“气”“固”变化过程,表明配合物能形成较好的LB膜。分子在膜中主要以倾斜的方式排列。以Z型累积方式沉积于金制梳状电极上的LB膜能导电,属于半导体材料,碘掺杂可改善膜的电导。膜电极的气敏特性研究发现,配合物对氨气有专一的气敏特性,氨气浓度为33ppm时即有响应,且灵敏度高。  相似文献   

9.
四羧基酞菁配合物修饰电极氧化草酸及L-半胱氨酸的活性董国孝李纪生(中国科学院化学研究所,北京100080)庄瑞舫(南京大学配位化学研究所,南京210093)关键词四羧基酞菁修饰电极草酸L-半胱氨酸循环伏安法金属酞菁配合物由于结构稳定、色彩鲜艳,已作为...  相似文献   

10.
信息科技的高速发展使得开发有机小分子半导体越来越成为迫切的现实需求。而基于酞菁分子独特的π共轭体系,超高的稳定性以及稀土元素丰富的电子能级结构,三明治型酞菁的稀土配合物在构建场效应晶体管方面具有很多优势。事实证明,三明治型酞菁的稀土配合物可以用来构建双极性场效应晶体管,其对电子和空穴载流子都有很高的迁移率。而改变三明治型酞菁的稀土配合物的分子结构和自组装纳米结构都可以调控其所形成的分子半导体器件的特点和性能。本文对近期这些非常有意义的研究进展进行了总结。  相似文献   

11.
The role of water structure around model membrane systems (e.g., liposomes) on phase transition of the lipid dipalmitoyl phosphatidylcholine was investigated. Water structure was altered by changing pH and by addition of solutes which are known breakers and makers of water structure. The structure makers broadened the zone of transition and changed the overall phase transition profile, while the main effect of structure breakers was to cause a shift in the transition temperature. The observed variation of Chapman transition temperature and broadening of zone of transition with varying pH is discussed in terms of altered water structure around the membrane–aqueous interface. Binding studies with the dye 1-anilino-8-napthalene sulfonate showed that structure makers or breakers did not bind to the liposome surface directly. Thus the structure makers and breakers act on the membranes perhaps by altering the water structure differentially. Possible associated mechanisms of action are discussed.  相似文献   

12.
The fundamental importance of the electronic structure of molecules is widely recognized. To get reliable electronic structure of protein in aqueous solution, it is necessary to construct a simple, easy-use equivalent potential of water molecules for protein's electronic structure calculation. Here, the first-principles, all-electron, ab initio calculations have been performed to construct the equivalent potential of water molecules for the electronic structure of glutamic acid, which is a hydrophilic amino acid and is negatively charged (Glu(-)) in neutral water solution. The main process of calculation consists of three steps. Firstly, the geometric structure of the cluster containing Glu(-) and water molecules is calculated by free cluster calculation. Then, based on the geometric structure, the electronic structure of Glu(-) with the potential of water molecules is calculated using the self-consistent cluster-embedding method. Finally, the electronic structure of Glu(-) with the potential of dipoles is calculated. Our calculations show that the major effect of water molecules on Glu(-)'s electronic structure is lowering the occupied electronic states by about 0.017 Ry, and broadening energy gap by 12%. The effect of water molecules on the electronic structure of Glu(-) can be well simulated by dipoles potential.  相似文献   

13.
崔磊  赖小萍  王帆  顾斌 《无机化学学报》2009,25(10):1885-1888
CdSe是Ⅱ-Ⅵ族半导体材料中一种重要的半导体材料,它有闪锌矿和纤锌矿两种不同的结构,带隙较窄,具有优良的电光特性和广泛的应用前景,得到了人们的广泛关注[1-3].  相似文献   

14.
《Liquid crystals》1999,26(7):1059-1065
A simple model of the formation of the chevron structure and tilted layer structure in the smectic C liquid crystal phase from the bookshelf structure in the smectic A phase is considered. Energetic considerations of this system indicate that in the absence of layer pinning forces at the surface, a transition to the tilted structure is expected. However, combining the model with 'weak' surface positional anchoring effects allows the chevron structure to form.  相似文献   

15.
The present contribution deals with one of the possible structure types of nongraphitic carbon adsorbents. The proposed structure consists of infinite strips of condensed aromatic rings arranged into a hexagonal honeycomb-like structure with the edge formed only by sp2 carbon atoms. Quantum chemical calculations were performed at the UHF/STO-3G level using the CRYSTAL95 program package for periodical approach. The extremely high adsorption ability of some low-density paramagnetic carbon forms can be elucidated by the presence of the sp2 honeycomb carbon structure and the specific properties of its electronic structure.  相似文献   

16.
The effects of seven tertiary amine accelerators on curing of bisphenol-type epoxide resins using azelaic acid as a curing agent have been investigated. The structure of the cured resins is characterized and reaction and structure schemes are proposed. The reaction mechanism and the resulting structure of the resin depend on the basicity of the accelerator. With increasing accelerator basicity crosslinking in the cured resin increases. Characterization results indicate that the network structure consists of ether bonds or a mixture of ether and ester bonds; the linear structure consists of only ester bonds. The structure and, therefore, the properties of the cured epoxide resin may thus be regulated by selection of the amine basicity.  相似文献   

17.
闫寿科 《高分子科学》2013,31(6):841-852
The dependence of properties on the structure and morphology of semicrystalline polymers offers an effective way to tailor the properties of these materials through structure control. To this end, establishing the structure and property relationship is of great importance. For a right characterization of the crystal structure, several techniques can be used. Among these techniques, electron diffraction has its advantage for determining the crystal structure related to specific formation condition since it can combine with bright and dark fields observation of the sample. This feature article describes the application of electron diffraction in determining the crystal structure of semicrystalline polymers with elaborately selected examples. We focus on how the electron diffraction can be used to disclose the crystal structure, mutual orientation of different crystals, as well as the disorders included in the polymer crystals.  相似文献   

18.
功能高分子的设计思想是功能高分子课程的灵魂 ,它以高分子物理学所研究的结构与性能之间关系为基础。结构与性能之间的关系是贯穿功能高分子课程始末的主线。功能高分子材料有三种设计途径 ,即化学结构设计、聚集态结构设计和复合结构设计  相似文献   

19.
20.
We study the annihilation of hedgehog-antihedgehog defects in confined nematic liquid crystals using Brownian molecular dynamics simulations. After the collision, merging of defects, and building a loop disclination structure, system can experience a structural transition into another nematic structure, triggered by a nucleation of loop disclination structure. In our rough theoretical approach we calculate the size of the emerged loop structure as the function of the typical size of the confining cavity. Attention is paid also to the dynamics of the loop structure after collision.  相似文献   

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