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1.
Physicochemical issues are discussed which are relevant to chemists interested in the synthesis of unknown compounds to serve as precursors to organic metals. Molecular topics are emphasized, physical and structural concepts which motivate synthetic activity in chalogen chemistry are presented, and new results in selenium and tellurium systems are summarized. Two model representations for donor molecular structures based on polyenes and polyacenes are presented and known examples are discussed. Quantitative correlations between gas phase vertical ionization potential and solution electrochemical redox potential are examined using donors of interest for organic metals as data. Limitations of such correlations and consequences of these shortcomings are given. Finally, possible future directions for several of these topics are posed.  相似文献   

2.
李辉 《辽宁化工》2012,41(2):191-192,209
采用Gc-MS分析方法,研究了稠油石化污水中有机物分布特征,分析结果表明,稠油石化污水中有机物以烷烃、酚类和有机酸为主并含有一定量的PAHs,污水中有机物分子量140以下的以酚类为主,分子量在140以上的有机物多为烷烃和PAHs,其中烷烃类主要为分子量在200~350的饱和烷烃为主,PAHs以含不同数量甲基取代基的萘为主.  相似文献   

3.
Reference is made to historical types. Practical conditions are discussed, types of glazes are given, and methods of application are outlined. There are also comments in connection with one-fire products. The processes involved are discussions A-3 and A-4: “The Italian Majolica Process,”“Painting over Tin Enamels,” are so closely related that they are taken together.  相似文献   

4.
流化床造粒的研究进展   总被引:2,自引:0,他引:2  
王可  程榕  杨阿三 《河南化工》2003,(3):1-3,47
简述了流化床造粒的主要方法,阐述了造粒的机理主要是团聚和涂布两种过程,总结了影响造粒的因素和研究造粒过程中提高团聚效率的方法,并对流化床今后的研究方向进行了展望。  相似文献   

5.
国内外染料工业发展新动向   总被引:1,自引:1,他引:1  
本文阐述了国内外染料工业发展的新动向,指出了国外染料市场趋势和发展新特点:染料企业重组已趋平稳和进一步确立我国作为世界染料生产和供应中心的地位,在国际上设置"技术壁垒"和"贸易壁垒"的力度进一步加强,新染料的开发放到比较重要的地位,不断适应纺织工业新的着色要求;还指出了我国染料工业的发展新特点:市场活跃新品不断,出口增长,连创新高,新兴基地,发展壮大。注重染料质的提高,采用新技术和清洁工艺生产是我国染料工业发展的重中之重。有7篇参考文献。  相似文献   

6.
《分离科学与技术》2012,47(2-3):581-617
Abstract

The separation methods which are used in the hydro-metallurgical field are reviewed and compared. Some processes in solvent extraction in use for recovery of crucial metals which are important to the U.S. defense and economy are presented. Various commercial extractants are reviewed and categorized. Other methods such as liquid membranes and ion exchange resins used for dilute metal ions separation are summarized. These methods are compared with solvent extraction. Problems to overcome in the further development of these separation methods are also identified and discussed in this paper.  相似文献   

7.
Hygienic impeccable surfaces are, e.g., in food technology and healthcare facilities conditionally essential. Does a presence of fine particular contamination occur, adhesion forces between particles and surfaces are relevant. In this paper the cleaning‐process of materials, which are often used in cleanrooms are focused. The surface properties, which influence the dislodgement of particles are observed. There are two groups of materials used for the experiments, which are commonly used in hygienic relevant places in healthcare facilities.  相似文献   

8.
During processing of vegetable oils, certain by-products and waste materials are generated. Where and how the by-products are recovered and used and how the solid wastes are handled and disposed of are considered. Several suggestions for the future are explored.  相似文献   

9.
Papers and any printable surface that have value are subject to forgeries. Various methods of security printing are identified and utilizing luminescent pigments as security items are discussed. Problems with classical luminescent pigments because of toxicity and particle size are identified. A new range of luminescent pigments that are either excited by UV or IR are presented and their chemical and physical characteristics defined. Also samples from actual security applications are given. © 1995 John Wiley & Sons. Inc.  相似文献   

10.
减轻环境压力利用粉煤灰生产肥料   总被引:1,自引:0,他引:1  
介绍粉煤灰的基本性质,总结目前各种粉煤灰肥料的特点和生产方法,对生产、作用机理进行分析,简单论述粉煤灰肥料的应用方法,并提出应注意的问题.  相似文献   

11.
Heating value of biomass and biomass pyrolysis products   总被引:3,自引:0,他引:3  
K. Raveendran  Anuradda Ganesh 《Fuel》1996,75(15):1715-1720
Studies conducted on the heating value of various types of biomass components and their pyrolysis products such as char, liquids and gases are presented. Heating values of chars are comparable with those of lignite and coke; heating values of liquids are comparable with those of oxygenated fuels such as methanol and ethanol, which are much lower than those of petroleum fuels. Heating values of gases are comparable with those of producer gas or coal gas and are much lower than that of natural gas. It is also found that the heating values of products are functions of the initial composition of biomass; correlations are developed to express these. Also, correlations are developed which explain the influence of ash elements on heating values of the pyrolysis products and on percentage distribution of energy in the products.  相似文献   

12.
本文综述了多肽的液相分段合成方法,这些合成方法是近年来多肽和蛋白质合成领域中的一种发展趋势.详细介绍了天然化学连接、化学区域选择连接、施陶丁格连接等方法,并对这些方法进行了比较,指出其优点及不足并提出改进办法.最后对多肽合成技术的发展做了进一步展望.  相似文献   

13.
Cyclophanes是一类芳环通过烷基桥连接而成的大环化合物,是超分子化学中的受体,本文按全碳、含杂原子、笼形分类Cyclophanes,对其各类的合成进行综述。  相似文献   

14.
切削液及其添加剂的进展   总被引:6,自引:0,他引:6  
周建  陶德华  张建华 《化学世界》2001,42(12):659-661,634
对切削液的分类、组成及发展现状作了综述 ,详细分析了摩擦学添加剂的种类 ,特点和作用机理 ;分别概述了水基与油基辅助添加剂的种类及特点 ,介绍了基于环保而形成的一些研究热点。将纳米技术应用于切削液 ,合成新的稀土有机化合物作为切削添加剂等均具有良好的应用前景。  相似文献   

15.
张一宾 《世界农药》2011,33(3):10-12
介绍了近年来新开发的14个农药品种,其中indaziflam等6个产品为除草剂,ametoctradin等6个产品为杀菌剂,sulfoxaflor和fluensulfone为杀虫剂。  相似文献   

16.
偶氮类有机光导体的发展趋势   总被引:1,自引:0,他引:1  
综述了偶氮类有机光导体的发展历程、结构及性能,讨论了其性能的主要因素,归纳了偶氮类有机光导材料的主要类型,举例说明了合成过程,对偶氮光导体的发展前景作出了展望。有37篇参考文献。  相似文献   

17.
丁二烯萃取装置聚合物产生原因分析及对策   总被引:3,自引:0,他引:3  
丁二烯抽提装置因其萃取溶剂二甲基甲酰胺及丁二烯本身的特性 ,在运行过程中易产生各类聚合物 ,堵塞设备、管线、阀门等 ,制约装置的运行负荷和周期。从理论上分析了装置中各类聚合物的特性及危害 ,总结聚合物产生的原因 ,结合生产实际 ,提出了相应的对策  相似文献   

18.
Some of the material investigations which are necessary before a glass-reinforced plastic (GRP) can be selected for use in large marine structures are described. The requirements of large-scale manufacture are as important as mechanical performance when the basic constituents of the laminate, the polyester resin and the glass reinforcements, are being selected. Various production problems which can arise, and the need for detailed quality control, are discussed. Other areas of investigation which are appropriate are the performance of joints and fasteners, and the influence of the glass reinforcement on the impact resistance of the laminate.  相似文献   

19.
Albert Erkip 《Polymer》2004,45(2):641-648
The fluctuations of residues of proteins about their equilibrium configurations are analyzed by the Langevin equation. Residue pairs that are covalently bonded and those that are within a given cutoff distance of each other are assumed to be connected by linear springs. The actions of the solvent and intramolecular interactions on each residue are treated as random noise. The correlations of fluctuations resulting from the solution of the Langevin equation are observed to be identical to those obtained by the Gaussian Network Model based on equilibrium statistical mechanics. The time-delayed correlations of fluctuations, and the response of the protein to a given frequency and to a window of frequencies are determined. The fluctuations of the residues resulting from a given fixed externally applied frequency are evaluated for different modes of the system. Synchronous and asynchronous components of correlations for different modes are formulated. The findings of the present paper are applied to the 241 residue protein S. marcescens endonuclease (1QL0).  相似文献   

20.
Scanning tunneling microscopy and spectroscopy are used to study local electronic variations across a surface containing one monolayer of copper on TiO2 rutile (001). The interactions that occur at the metal–oxide interface when the sources of the copper are segregation from the bulk and ultra-high-vacuum deposition are compared by characterizing the associated surface morphologies and electronic properties. The morphologies of these surfaces are similar in that the copper forms clusters; they are dissimilar in that copper features exist on two size scales on the segregated surface, whereas the deposited copper clusters are uniform in size and are aggregated. The electronic properties of the two surfaces also are found to differ: the copper-segregated surface is insulating, whereas the copper-deposited surface is conductive. The electronic properties are discussed in terms of the effects of surface-charge and ionic-charge concentration gradients.  相似文献   

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