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1.
The interactions of an organic anion, 1-pyrenesulfonate (PS), with γ-cyclodextrin (γ-CD) and organic cations such as quaternary ammonium compounds (or organic anions such as 1-decanesulfonate) have been examined by means of absorption and fluorescence spectroscopy. At a low concentration of PS, γ-CD forms a 1:1 inclusion complex with PS. PS forms organic cation–organic anion complexes with quaternary ammonium compounds. The organic cation–organic anion complexes of PS form ternary inclusion complexes with γ-CD. Equilibrium constants for the formation of these complexes have been evaluated from the fluorescence intensity change. As an alkyl chain in the quaternary ammonium compound is lengthened, the equilibrium constant for the formation of the ternary inclusion complex is increased. Although PS does not form complexes with organic anions such as 1-decanesulfonate, the organic anions are bound to the γ-CD cavity accommodating a PS molecule to form ternary inclusion complexes. However, the equilibrium constants for the organic anions (1-decanesulfonate etc.) are significantly less than those for the quaternary ammonium compounds. The small equilibrium constants for the organic anions can be ascribed to the electrostatic repulsion between PS and the organic anions.  相似文献   

2.
The widespread concern of bovine spongiform encephalopathy (mad cow disease) has raised questions about the possibility of residual organic material in bovine-derived bone graft materials. Conflicting reports have shown both the presence and the absence of organic materials in bone derived products. This study compared residual organic levels in two commercial bone graft products: a bovine bone product treated chemically and at low temperature, and a bovine bone product treated at high temperature. In this study, organic carbon, the primary constituent of organic materials, is defined as carbon that is not liberated as CO2 upon acidification (i.e. non-carbonate carbon). Three approaches to the determination were used: (1) organic carbon was calculated as the difference between total carbon determined by high temperature combustion and carbonate carbon determined by acid evolution of CO2. (2) Organic carbon was determined by measuring total carbon by high temperature combustion of a sample that had been pretreated with acid to remove all carbonate. (3) The total organic carbon remaining in solution after acid dissolution was determined. In addition, organic nitrogen was determined as the difference between total Kjeldahl and ammonia nitrogen. Total nitrogen values were confirmed using an instrumental nitrogen analyzer. No detectable organic carbon or organic nitrogen was observed in the high temperature bone product. In the low temperature treated bovine product, however, approximately 2000 μg/g organic carbon was measured by all three methods, as well as 15 μg/g organic nitrogen.  相似文献   

3.
This review provides a general introduction to organic field-effect transistors and their application as chemical sensors. Thin film transistor device performance is greatly affected by the molecular structure and morphology of the organic semiconductor layer. Various methods for organic semiconductor deposition are surveyed. Recent progress in the fabrication of organic thin film transistor sensors as well as the correlation between morphology and analyte response is discussed.  相似文献   

4.
合成钛硅分子筛TS-1的一种新方法   总被引:4,自引:0,他引:4  
In both conventional method[1] and modified method[2] ,organic Si and Ti alkoxides were used as Si source and Ti source respectively, and only strong organic base was used. So this system may be called as organic synthesis one (see Fig 1 )Thangaraj et al[3] reported that in the organic synthesis system only organic strong base TPAOH can be used.  相似文献   

5.
Large π-conjugated compounds are promising building blocks for organic thin-film electronics such as organic light-emitting diodes, organic field-effect transistors, and organic photovoltaics. Utilization of porphyrins and phthalocyanines for this purpose is highly fascinating because of their excellent electric, photophysical, and electrochemical properties as well as intense self-assembling abilities arising from π-π stacking interactions. This paper focuses on fundamental aspects of self-assembled structures that have been obtained from porphyrin and phthalocyanine building blocks and more complex composites for photoinduced charge separation and charge transport toward the potential applications to organic thin-film electronics.  相似文献   

6.
汪文龙  李存耀  张恒  张江威  卢兰露  姜政  崔立峰  刘宏光  严丽  丁云杰 《催化学报》2021,42(7):1216-1226,中插76-中插81
多孔有机笼(POCs)由英国利物浦大学的Cooper教授在2009年首次合成,这种多孔小分子材料的出现具有两方面重要意义:(1)开拓了多孔材料领域的一个全新分支,改变了人们对多孔材料的传统认知;(2)由于POCs材料由离散的小分子堆积而成,可溶解于一些常用的有机溶剂中,因此其在材料制备方面具有很好的"溶液成型"性能,该优势是三维延伸网状多孔材料所不具备的.POCs本质上是一种"中心带孔"的有机小分子,由刚性有机分子砌块收敛堆叠而成,其特殊结构在气体吸附与分离等方面表现出很好的应用前景.不同于传统空间延伸网状框架材料(如金属-有机框架材料和共价有机框架材料)及多孔有机聚合物(POPs)材料,POCs是一种在大多数有机溶剂中可溶解的小分子材料,因此在均相催化领域也有很好的应用前景.作为最为经典的有机配体,三苯基膦(PPh3)在金属有机化学和均相催化领域应用十分广泛,如目前均相催化工业应用最成功的典范之一氢甲酰化反应,大多数情况下使用的是PPh3与Rh形成的络合物催化剂.本文首先将PPh3进行醛基官能团化,通过醛基和氨基的收敛缩合形成POCs材料,合成了基于PPh3配体的准多孔有机笼(POC-DICP),利用得到的多孔有机笼制备出类Rh/PPh3均相催化体系的Rh/POC-DICP络合催化体系,并将其应用于氢甲酰化反应.相比于经典的Rh/PPh3均相催化体系,该Rh/POC-DICP催化体系在氢甲酰化反应中不仅展示出了更高的活性和目标产物醛的选择性(醛的化学选择性为97%,醛的正异构比为1.89),而且可以很方便地从均相反应体系中沉淀回收(通过调整溶剂体系极性).在氢甲酰化反应中,Rh/POC-DICP体系显示出了良好的底物适用性,在己烯、庚烯、辛烯和苯乙烯的氢甲酰化反应中均表现出良好的催化活性和醛选择性,同时催化剂回收使用4次,未见催化性能明显下降.X射线单晶衍射、同步辐射及DFT计算等结果表明,Rh/POC-DICP催化体系在氢甲酰化反应中具有较高活性和选择性的原因是POC-DICP多孔有机笼分子的有利的空间咬合角(123.88o)和P原子上相对的缺电子效应.本文设计合成的PPh3衍生的多孔有机笼不仅拓宽了多孔有机笼材料在催化领域的应用,而且为新型配体及络合催化剂的设计、合成及修饰提供了新的思路.  相似文献   

7.
有机复合光电导材料及器件研究进展   总被引:5,自引:0,他引:5  
有机光电导复合材料已经成为当前国际上有机光电材料科学研究的前沿与热点之一。复合化是大幅度提高有机半导体材料光电导性能的有效手段,本文主要从有机光电导材料的复合化角度,综述了新型高效的多种有机复合光电导材料体系的制备及其光电导性能,初步解释了其相应的复合原理和光电导机理,并介绍了其在单层型光电导器件中的研究进展。最后提出了制备高性能有机光电导复合材料及单层型光电导器件的几点建议。  相似文献   

8.
汪文龙  李存耀  张恒  张江威  卢兰露  姜政  崔立峰  刘宏光  严丽  丁云杰 《催化学报》2021,42(7):1216-1226,中插76-中插81
多孔有机笼(POCs)由英国利物浦大学的Cooper教授在2009年首次合成,这种多孔小分子材料的出现具有两方面重要意义:(1)开拓了多孔材料领域的一个全新分支,改变了人们对多孔材料的传统认知;(2)由于POCs材料由离散的小分子堆积而成,可溶解于一些常用的有机溶剂中,因此其在材料制备方面具有很好的"溶液成型"性能,该优势是三维延伸网状多孔材料所不具备的.POCs本质上是一种"中心带孔"的有机小分子,由刚性有机分子砌块收敛堆叠而成,其特殊结构在气体吸附与分离等方面表现出很好的应用前景.不同于传统空间延伸网状框架材料(如金属-有机框架材料和共价有机框架材料)及多孔有机聚合物(POPs)材料,POCs是一种在大多数有机溶剂中可溶解的小分子材料,因此在均相催化领域也有很好的应用前景.作为最为经典的有机配体,三苯基膦(PPh3)在金属有机化学和均相催化领域应用十分广泛,如目前均相催化工业应用最成功的典范之一氢甲酰化反应,大多数情况下使用的是PPh3与Rh形成的络合物催化剂.本文首先将PPh3进行醛基官能团化,通过醛基和氨基的收敛缩合形成POCs材料,合成了基于PPh3配体的准多孔有机笼(POC-DICP),利用得到的多孔有机笼制备出类Rh/PPh3均相催化体系的Rh/POC-DICP络合催化体系,并将其应用于氢甲酰化反应.相比于经典的Rh/PPh3均相催化体系,该Rh/POC-DICP催化体系在氢甲酰化反应中不仅展示出了更高的活性和目标产物醛的选择性(醛的化学选择性为97%,醛的正异构比为1.89),而且可以很方便地从均相反应体系中沉淀回收(通过调整溶剂体系极性).在氢甲酰化反应中,Rh/POC-DICP体系显示出了良好的底物适用性,在己烯、庚烯、辛烯和苯乙烯的氢甲酰化反应中均表现出良好的催化活性和醛选择性,同时催化剂回收使用4次,未见催化性能明显下降.X射线单晶衍射、同步辐射及DFT计算等结果表明,Rh/POC-DICP催化体系在氢甲酰化反应中具有较高活性和选择性的原因是POC-DICP多孔有机笼分子的有利的空间咬合角(123.88o)和P原子上相对的缺电子效应.本文设计合成的PPh3衍生的多孔有机笼不仅拓宽了多孔有机笼材料在催化领域的应用,而且为新型配体及络合催化剂的设计、合成及修饰提供了新的思路.  相似文献   

9.
In the past decade, tremendous progress has been made in organic field-effect transistors (OFETs). Their real applications require further development of device performance. OFETs consist of organic semiconductors, dielectric layers, and electrodes. Organic semiconductors play a key role in determining the device characteristics. The properties of the organic semiconductors, such as molecular structure and packing, as well as molecular energy levels, can be properly controlled by molecular design. Therefore, we designed and synthesized a series of organic molecules. The synthesized organic semiconductors exhibit excellent field-effect properties due to strong intermolecular interactions and proper molecular energy levels. Meanwhile, the influence of the device fabrication process, organic semiconductor/dielectric layer interface, and organic layer/electrode contact on the device performance was investigated. A deep understanding of these factors is helpful to improve field-effect properties. Furthermore, single-crystal field-effect transistors are highlighted because the single-crystal-based FETs can provide an accurate conducting mechanism of organic semiconductors and higher device performance as compared with thin film FETs.  相似文献   

10.
离子液体载催化剂和载试剂在有机合成中的应用   总被引:6,自引:0,他引:6  
刘宝友  韩菊  董建芳  魏福祥  程彦海 《有机化学》2007,27(10):1236-1243
综述了离子液体载催化剂和载试剂在有机合成中的应用进展. 离子液体载催化剂是针对离子液体中催化剂难以回收利用的问题提出来的, 它不仅可以实现均相催化, 而且反应产物容易分离, 催化剂可以循环使用. 离子液体载有机试剂合成, 又称为离子液体相有机合成, 具有固相反应产物纯度高和液相反应反应快的优点. 在离子液体载无机试剂的反应中, 反应物毒性降低, 反应条件温和, 产物选择性好.  相似文献   

11.
Thanks to the pure blue emitting, high planarity, electron rich and ease of chemical modification, pyrene has been thoroughly investigated for applications in organic electronics such as organic light emitting diodes (OLEDs), organic field effect transistors (OFETs), and organic solar cells (OSCs). Especially, great progresses have been made of pyrene-based organic semiconductors for OFETs in past decades. Due to the difference of molecular structure, pyrene-based organic semiconductors are divided into three categories, pyrene as terminal group, pyrene as center core and fused pyrene derivatives. This minireview gives a brief introduction of the structure-property relationship and application in OFETs about most of pyrene-based semiconducting materials since 2006, illustrating that pyrene is a good building block to construct semiconductors with superior transport property for OFETs. Finally, we provide a summary concerning the methodology to improve the transport property of the pyrene-based semiconducting materials as well as an outlook.  相似文献   

12.
Porous organic materials are an emerging class of functional nanostructures with unprecedented properties. Dynamic covalent assembly of small organic building blocks under thermodynamic control is utilized for the intriguingly simple formation of complex molecular architectures in one‐pot procedures. In this Review, we aim to analyze the basic design principles that govern the formation of either covalent organic frameworks as crystalline porous polymers or covalent organic cage compounds as shape‐persistent molecular objects. Common synthetic procedures and characterization techniques will be discussed as well as more advanced strategies such as postsynthetic modification or self‐sorting. When appropriate, comparisons are drawn between polymeric frameworks and discrete organic cages in terms of their underlying properties. Furthermore, we highlight the potential of these materials for applications ranging from gas storage to catalysis and organic electronics.  相似文献   

13.
There has been extensive research on the development of organic optoelectronic devices, such as organic light‐emitting diodes, organic field‐effect transistors, and organic solid‐state lasers from various viewpoints, ranging from basic studies to practical applications. As organic materials are used as solids in these devices, the importance of organic chromophores that exhibit intense emissions of visible light in the solid state is greatly increasing in the field of organic electronics. However, highly efficient emission from organic solids is very difficult to attain because most organic emitting materials strongly tend to cause concentration quenching of the luminescence in the condensed phase. Therefore, in order to generate and improve organic optoelectronic devices, it is necessary to design novel chromophores that exhibit superior solid‐state emission performance. This Focus Review covers the recent development of highly emissive organic small molecules whose photoluminescence quantum yields in the solid state have been reported. Following the introduction, the photophysical processes of excited molecules are briefly reviewed. Subsequently, organic solid fluorophores are described with an emphasis on the characteristics of their molecular structures.  相似文献   

14.
纳米二氧化硅包覆颜料黄的研究   总被引:3,自引:0,他引:3  
采用静电自组装技术成功地将纳米二氧化硅粒子包覆在颜料黄的表面.研究结果表明,预吸附的聚电解质层数显著影响纳米二氧化硅的吸附量.随着包覆二氧化硅层数的增加,覆盖率逐渐增加,但包覆三层二氧化硅后,覆盖趋于平衡.吸附的纳米二氧化硅不仅可以提高颜料黄的亲水性,而且还能够散射紫外线,尤其是波长小于270nm的紫外线,提高了颜料黄的耐候性,同时又不影响颜料黄本身的颜色.  相似文献   

15.
锂离子电池有机电解液研究   总被引:18,自引:1,他引:17  
庄全超  武山  刘文元  陆兆达 《电化学》2001,7(4):403-412
本文分析了影响有机电解液电导率的主要因素 ;总结了有机电解液的一般特点 ,从有机溶剂和电解质锂盐两个方面介绍了有机电解液的化学和电化学 ;概述了各常用有机溶剂的性质和近年来的研究状况 ;综述了有机电解液在电解质锂盐、有机溶剂和添加剂三个方面的研究进展 .文章最后对有机电解液研究的现状作了简要的评论  相似文献   

16.
End-product identification of organic pollutants during oxidation water treatments is of environmental concern due to their potential toxicity. In this work the coupling of ion chromatography (IC), equipped with a membrane ion suppressor, and electrospray ionization mass spectrometry (ESI-MS) has been successfully exploited for the identification of novel low molecular weight organic acids formed as final by-products of 2,4-dichloro-phenol (DCP) degradation by Fenton's reagent, an oxidation method widely employed to degrade recalcitrant organic pollutants in industrial wastewater. The IC-ESI-MS analytical set-up not only allowed the detection of known organic acids but also the identification of 13 new low molecular weight organic acids as a result of extensive oxidation of the parent organic pollutant. Some of the novel organic acids were shown to be chlorine containing by-products and, consequently, of environmental concern. The analytical set-up could be used for characterizing the unknown organic carbon fraction arising from oxidation water treatments.  相似文献   

17.
通过在RPHPLC固定相C18表面键合氨基硅烷,引入氨基基团,将有机改进剂固定至硅胶键合相表面,克服了固定相表面硅羟基对含氮有机化合物的不可逆吸附。以最简单的CH3OH-H2O洗脱体系即能获得含氮有机物的最佳分离,从而可简化分离操作,提高柱寿命,降低分离成本。  相似文献   

18.
无机材料电子迁移率高、光谱响应范围与太阳光谱匹配,而有机材料价格低廉、合成方法简单、容易制作在基底上,因此在太阳能电池中具有更广阔的应用前景。 目前,阻碍有机太阳能电池发展的主要原因是材料的载流子迁移率低、器件稳定性差、吸收光谱与太阳光谱不匹配,导致光电转换效率较低。 若能将有机、无机材料二者的优点相结合,将可提高有机太阳能电池的能量转换效率。 目前的研究已经取得了一定进展,无机材料在受体层、阴极缓冲层、阳极缓冲层中的应用均不同程度地提高了有机太阳能电池的能量转换效率。 本文综述了目前该领域的研究现状,并对今后的研究提出了展望。  相似文献   

19.
本文以对氯苯酚(4-CP)、对硝基苯酚(4-NP)和罗丹明B(Rh B)为模型有机物(以4-CP和4-NP为小分子模型有机物,以Rh B为大分子模型有机物),分别研究了185 nm UV对水中这3种模型有机物的降解规律、性能和效果.研究结果表明,185 nm UV直接对水中4-CP、4-NP和Rh B有很好的降解效果.研究内容包括:185 nm UV降解模型有机物的浓度、TOC(Total organic carbon)浓度、185 nm UV降解模型有机物过程中溶液pH及电导率变化、以及降解模型有机物过程中产生的无机离子等几个方面.  相似文献   

20.
田明 《高分子学报》2001,18(5):639-644
提出了以具有纳米尺寸孔径及孔壁厚度的MCM 48作为无机基体、以无机 有机原位自组装的方法形成纳米网络粒子 .研究结果表明 ,在一定实验条件下 ,有机相可进入无机相的三维孔道自组装形成立方有序结构的纳米网络复合粒子 .通过研究纳米网络粒子在极性介质和非极性介质中的分散发现 ,有机相的存在有利于纳米网络粒子的分散  相似文献   

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