TRPing the switch on pain: an introduction to the chemistry and biology of capsaicin and TRPV1

Capsaicin has elicited great interest for many centuries due to its noticeable culinary and medical properties. The discovery of its receptor, TRPV1, sparked an explosion of interest in TRPV1 and the development of TRPV1 agonists and antagonists. This tutorial review provides an introduction to the history of both capsaicin and TRPV1. Two TRPV1 antagonists that are undergoing clinical trials are highlighted, as are some light-activated molecular tools that are enabling the intracellular study of this protein. This article will be of interest to chemists and biologists with an interest in TRPV1, cell signalling, or medicinal and biological chemistry.     

Application of neutron activation analysis for trace element determinations in biological materials

Over the past three decades, more and more interest has been focused on trace eleemnts in biological materials. This increasing interest has gone hand in hand with the continuous improvement of analytical techniques. Neutron activation analysis has proven to be a most suitable method for the quantitative determination of a wide variety of trace (0.01–100 μg g^?1) and ultratrace (<0.01 μg g^?1) elements in biological materials. This technique has even played a preponderant role in this field.     

Oil-soluble colloidal additives

The synthesis and study of oil-soluble metal carbonate colloids is a continuing area of interest within the field of lubricant additives. The acid neutralisation properties of these species have been studied for several years. More recently, the introduction of exhaust gas circulation (EGR) systems to combustion engines has increased demands upon the acid neutralisation performance of these additives. This has prompted a resurgence of interest in the reactivity of metal carbonate colloidal additives.     

Current role of capillary electrophoretic/electrokinetic techniques in forensic toxicology

The current application of capillary electrophoresis in forensic toxicology has been critically reviewed with special focus on the areas where this technique has shown real advantages over chromatographic methods. For example, capillary electrophoresis has been most successfully applied to the chiral analysis of some drugs of forensic interest, including amphetamines and their congeners. Another typical application field of capillary electrophoresis is represented by protein analysis. Recently, special interest has been paid to carbohydrate deficient transferrin (CDT), the most important biological marker of chronic alcohol abuse. Other specific applications of capillary electrophoresis of potential forensic toxicological concern are also discussed. The review includes 62 references.     

Mixing in the sample loop of the loop-type interface in coupled LC-GC

During introduction of an LC fraction into the sample loop of the loop-type interface mixing occurs between the fraction of interest and the material previously eluted from the LC. Such mixing may not only result in losses of the solute material of interest, but also in contamination of the fraction of interest with material from which it was supposed to have been isolated. Experimental determination of the extent of mixing has led to the conclusion that whereas the effects are negligible under some conditions, in some circumstances the mixing can cause severe problems.     

The Biological production of ethanol from synthesis gas

Applied Biochemistry and Biotechnology - There has been considerable interest recently in the production of liquid fuels from coal through direct or indirect liquefaction. A culture has been...     

Catalytic concepts for the enantioselective synthesis of alpha-amino and alpha-hydroxy phosphonates

The enantioselective synthesis of alpha-amino- and alpha-hydroxy phosphonates by catalytic processes has attracted considerable interest in the last few years, not least because of the pharmaceutical interest in such compounds. This article contains a compilation of the asymmetric synthesis methods developed to date. The described synthetic routes are based on different catalytic concepts, namely, hydrogenation, reductions, dihydroxylation, aminohydroxylation, and hydrophosphonylation.     

Reduction of Aromatic Nitro Compounds under Solvent-free Condition Using Almnina-suppored Hydrazine/Fe2 (NO3)3· 9H2O

The application of microwave techniques for chemical synthesis has attracted considerable interest in recent years because of their enhanced selectivity, reduced reaction time, easier work-up procedure. Aromatic amines are widely used as intermediate for dyes, photographic materials, pharmaceutical and agricultural chemicals and as antioxidants. So, particularly intense interest has been directed toward the synthesis of these compounds. Reduction of aromatic nitro compounds is one of the important routes to prepare them. Generally, the processes have been carried out in solvent. [ 1 ～ 6] The drawback of these methods is long reaction time.     

Gold and silver assisted synthesis of five-membered oxygen and nitrogen containing heterocycles

The investigation of methods for the chemical synthesis is a growing area of interest due to increasing environmental issues. The use of catalysts in organic reactions has gained extensive interest. Metal and nonmetal catalysts provided a new improved alternative to traditional methods in modern synthetic chemistry. The aim of the present review is to focus on the applications of gold- and silver-catalytic systems for the synthesis of five-membered oxygen- and nitrogen-heterocycles.     

Asymmetric synthesis of hydroxyphosphonates

Hydroxyphosphonates have attracted considerable attention as biologically active compounds, enzyme inhibitors, and drugs. Over the last few years significant interest in the asymmetric synthesis and practical application of chiral hydroxyphosphonates has been reported, which shows the theoretical interest and the practical importance of hydroxyphosphonates. An overview of recent synthetic approaches to chiral hydroxyphosphonates and determinations of their absolute configuration is presented. Data on the practical applications of hydroxyphosphonates are also discussed.     

Seven and higher-membered oxygen heterocycles: Metal and non-metal

The investigation of methods for the chemical synthesis is a growing area of interest due to increasing environmental issues. The use of catalysts in organic reactions has gained extensive interest. Metal and nonmetal catalysts provided a new improved alternative to traditional methods in modern synthetic chemistry. The aim of present review is to focus on the applications of metals and nonmetals for the synthesis of seven and higher-membered O-heterocycles.     

Naphthalene and azulene adsorption on Pt(111). Extended Hückel calculations

Current interest on the chemisorption of aromatics on metal surfaces has both theoretical and applied aspects. No determination of adsorption energies     

Pd-H4SiW12O40基催化剂上乙烯直接氧化合成乙酸

The direct oxidation of ethene to acetic acid has the advantages of abundant raw materials and low cost of equipment[1],hence the research for this process has been of much interest in industry application.     

Seven-membered N-heterocycles: metal and nonmetal assisted synthesis

The investigation of facial synthetic methods for chemical synthesis is a growing area of interest due to increasing environmental issues. The use of catalysts in organic reactions has gained extensive interest. Metal and nonmetal catalysts provided a new improved alternative to traditional methods in modern synthetic chemistry. The aim of the present review is to focus on the applications of metals and nonmetals for the synthesis of seven-membered N-heterocycles.     

Nickel catalysis: six membered heterocycle syntheses

Abstract

The investigation of methods for the chemical synthesis is a growing area of interest due to increasing environmental issues. The use of catalysts in organic reactions has gained extensive interest. Metal and nonmetal catalysts provide a new improved alternative to traditional methods in modern synthetic chemistry. The aim of present review is to focus on the applications of nickel for the synthesis of six membered heterocylces.     

Ionic liquid: An efficient and recyclable medium for the synthesis of fused six-membered oxygen heterocycles

The investigation for replacement of organic solvents in chemical synthesis is a growing area of interest due to increasing environmental issues. The use of ionic liquid salts as solvents and catalysts in organic reactions has gained extensive interest. Ionic liquids provided a new environmentally benign and improved alternative to traditional methods in modern synthetic chemistry. The aim of present review is to focus on the applications of ionic liquids for the synthesis of fused six-membered oxygen heterocycles.     

Green synthesis of three- to five-membered O-heterocycles using ionic liquids

The investigation for replacement of organic solvents in organic synthesis is a growing area of interest due to increasing environmental issues. The use of ionic liquid salts as solvents and catalysts in organic reactions has gained extensive interest. Ionic liquids provided a new environmentally benign and improved alternative to traditional methods in modern synthetic chemistry. The aim of present review is to focus on the applications of ionic liquids for the synthesis of O-heterocycles.     

Optically pumped nuclear magnetic resonance of semiconductors

Optically pumped NMR (OPNMR) of direct gap and indirect gap semiconductors has been an area of active research interest, motivated by both basic science and technological perspectives. Proposals to enhance and to spatially localize nuclear polarization have stimulated interest in this area. Recent progress in OPNMR has focused on exploring the experimental parameter space in order to elucidate details of the underlying photophysics of optical pumping phenomena. The focus of this review is on recent studies of bulk samples of GaAs and InP, namely, the photon energy dependence, the magnetic field dependence, and the phase dependence of OPNMR resonances. Models for the development of nuclear polarization are discussed.     

An Efficient Solid-state Synthesis of 2-Thio-4-imidazolidinone Derivatives

In recent years increasingly intense interest has been directed towards the generation of small organic molecules by solid-state reactions, which has many advantages over conventional solution phase synthesis such as high efficiency and selectivity, easy separation and purification and environmental acceptability.     

TiO2-ZrO2复合氧化物负载的氧化钒催化剂用于丙烷氧化脱氢反应

 丙烷氧化脱氢反应制备丙稀酸，丙烯醛，由于其巨大的工业价值而成为催化领域研究的热点。该反应也可分为两步实现。即先由丙烷到丙烯，再由丙烯到丙稀酸，丙烯醛。后一步已成功的实现工业化，在低温下( £350℃)，使用钒基催化剂，丙稀酸，丙烯醛的产率可高达80%以上。但是，对于前一步，使用迄今为止最有效的V-Mg-O催化剂，在550℃的高温下，丙烯的产率仅为20%。而在如此高的温度下，在紧接着的第二步反应中，大部分的丙烯会直接转化为深度氧化产物（CO2, H2O）。所以，制备一种能在低温下有效实现丙烷氧化脱氢反应制丙烯的催化剂是由丙烷制备高产率的丙稀酸，丙烯醛的另一种途径。\r\n 催化剂V2O5/TiO2最显著的特点是它具有较高的低温催化活性。但是，作为载体材料，TiO2有一些缺点，如比表面较小，热稳定性较差，机械性能较低，抗磨损性较差等。相比之下，载体ZrO2就具有许多TiO2所不具备的优点。第一，ZrO2具有很大的比表面积（＞300m2/g），并且在高温下它也能保持较高的比表面积。第二，ZrO2的热稳定性，机械性能和抗磨损性都较好。第三，金属氧化物在ZrO2表面能够得到很好的分散。第四，ZrO2非常稳定，在烷烃氧化脱氢反应的条件下是惰性的，不参加反应。所以，如果向TiO2中掺杂ZrO2进行改性，能极大的提高其载体的表面积，热稳定性，机械性能和抗磨损性。那么复合载体TiO2-ZrO2很可能成为在低温下丙烷氧化脱氢制丙烯的极有潜力的催化剂载体材料。在本文中，我们采用溶胶-凝胶法，用廉价的无机盐作为初始材料制备了一系列不同TiO2/ZrO2质量比的TiO2-ZrO2复合氧化物作为催化剂载体并研究了这些催化剂用于丙烷氧化脱氢反应的催化活性。