拟除虫菊脂毒性与代谢的研究进展

近来拟除虫菊酯引起了国内外人们的重视,其发展亦较快。其中有二氯苯醚菊酯、苄氯菊酯、戊酸氰醚酯、溴氰菊酯等都是很有前途的杀虫剂,本文就有关拟除虫菊酯的毒性和代谢,作一概括介绍。一、毒性 (一)急性毒性从表1可以看出,拟除虫菊酯对哺乳动物的急性LD_(50)差异较大,多数口服毒性很低,其LD_(50)在700～14000毫克/公斤之间,但是有的静脉注射毒性较大。     

试论拟除虫菊酯类杀虫剂在水稻田中的应用

拟除虫菊酯杀虫剂具有高效、安全、广谱及对人畜低毒等特点,在农业上得以广泛应用,已成为杀虫剂市场的支柱之一。但由于其对鱼毒性高,我国禁止其在水稻田使用。随着我国高毒农药的禁用以及水稻害虫对常用药剂抗性的发展,水稻田用药将出现“缺口”。本文介绍了日本、菲律宾和越南等国家应用拟除虫菊酯杀虫剂防治水稻害虫的情况,推荐了一些稻田防虫的拟除虫菊酯品种,并提出了在我国拟除虫菊酯杀虫剂用于水稻田的几点建议。     

拟除虫菊酯类农药的中枢神经毒作用机制研究

拟除虫菊酯农药根据其在哺乳动物引起的神经毒性症状的不同可分为二类,第一类是不含2-氰基的拟除虫菊酯农药,如苄呋菊酯;第二类是含有2-氰基的拟除虫菊酯化合物,如溴氰菊酯、氯氰菊酯、氰戊菊酯等。后者杀虫活性极高,但毒性也较大。这二类拟除虫菊酯农药的主要毒理机制,即电生理效应基本相同,都能引起神经细胞膜钠离子通道功能异常,从     

本刊组织专题讨论:拟除虫菊酯在水稻田的应用

拟除虫菊酯杀虫剂在水稻田的应用是中国拟除虫菊酯发展30年学术研讨会的一个热点话题。由于大多数拟除虫菊酯杀虫剂对鱼贝类毒性较高，其在水稻田的应用长年以来在我国是个禁区(醚菊酯除外)。随着我国高毒农药的禁用以及水稻害虫对常用药剂抗性的发展，人们越来越多地将目光转向拟除虫菊酯。     

合成拟除虫菊酯对鱼毒性的评价

合成拟除虫菊酯是极有效的广谱杀虫剂,对哺乳动物和鸟禽毒性较低,但对鱼和一些水生无脊椎动物毒性极高。由于合成拟除虫菊酯不易挥发,水中溶解度又不高,并对光稳定只能在土壤中经微生物在酯键处分解代谢;依土壤中有机物含量多寡和pH的不同,其半衰     

拟除虫菊酯农药的毒性研究综述

本文论述了拟除虫菊酯的活性和结构,并对其毒性问题进行了研究和综述。     

拟除虫菊酯的毒性与温度的关系

杀虫剂的毒性受多种因素影响,其中包括温度。一般情况大多数有机磷和氨基甲酸酯类杀虫剂的毒性与温度是成正相关;但是滴滴涕和除虫菊酯却相反,毒性与温度是成负相关。最近研究表明,拟除虫菊酯类杀虫剂的毒性与温度也是成负相关。经济昆虫学杂志1982年第75卷第4期报道了几种拟除虫菊酯杀虫剂对三种鳞翅目害虫的毒性与温度关系。试验结果表明,二氯苯醚菊酯、戊酸氰醚酯、溴氰菊酯对粉纹夜蛾的毒性与温度是成负     

菊酸及其类似物的合成——方法讨论及其进展

天然除虫菊酯对哺乳动物毒性很低,经改变其化学结构之后,便研制出许多生物活性更高的合成拟除虫菊酯类杀虫剂。1973～1974年 Elliott 等人发现了对光稳定的二氯苯醚菊酯、溴氰菊酯等环丙烷型品种。另一方面,日本也积极开展了非三碳环型拟除虫菊酯的研究和工业化工作,其代表性化合物杀灭菊酯正在实际应用。     

合成拟除虫菊酯的国内外研究概况

一、天然及合成除虫菊酯的一般介绍拟除虫菊酯(Pyrethroids)是一类在天然除虫菊酯化学结构研究的基础上发展起来的仿生药物。天然除虫菊的特点是击倒力强、杀虫作用快、广谱性、易解降、对高等动物及鸟类毒性低、使用安全、不污染环境。除虫菊的产量有限,有效成份含量低,不耐光和热,残效期极短,长期以来仅用作家庭卫生(蚊香)杀虫剂,而不适用于农业生产。 M.S.Schechter,N.Green等在前人研究     

拟除虫菊酯的高效液相色谱分析

氯菊酯、氯氰菊酯,溴氰菊酯、甲氰菊酯、氰戊菊酯等拟除虫菊酯,由于其杀虫谱广,在环境中较稳定及对哺乳动物毒性低,对有机磷和有机氯农药有抗性的害虫使用该品也同样有效,在我国已得到迅速的发展。这些农药国内的分析主要采用气相色谱方法。GC分析过程中,拟除虫菊酯大都易产生热分解,应用上受到一定限制。自七十年代后期,国外已普遍采用高效液相色谱分析,结果准确、重现性好。此外,随着对高效拟除虫菊酯异构体     

Reactivity ratios of some substituted aromatic amines by linear graphical methods

Reactivity ratios of some halogen substituted aromatic amines have been determined by using Kelen-Tüd?s and Fineman-Ross linear graphical methods. On copolymerization with p-toluidine or p-nitrophenol as comonomer, the reactivity of halogen substituted aromatic amines was found to be in the order of their basic strength. However, this order of reactivity gets reversed when these halogen substituted amines are copolymerized with p-nitroaniline. This reversal of reactivity has been interpreted in terms of polarization and resonance stabilization of the monomeric species.     

棉铃虫对农药的交互抗性研究

以ＦＡＯ推荐的点滴法，对高抗性区山东省聊城棉铃虫进行了现状毒力测定。以沂蒙山区棉铃虫为敏感虫种，人工饲料饲养，以十种药剂对其进行抗性选育，经连续十五代，形为较为稳定的十个抗性种群，测出其交互抗性为棉铃虫对七个菊酯农药均产生了抗性和交互抗性，例题有程度差别；氰戊菊酯对硫磷有交互抗性，各菊酯与久效磷无效互抗性；各菊酯、久效磷与灭多威则有负交互抗性现象。     

Theoretical study of halogen-substituted benzene at a Si(111)7×7 surface

The adsorption of halobenzene (for halogens F, Cl, Br, and I) on Si(111)7×7 was investigated using AM1 quantum mechanical calculations. First the 1,4-cyclohexadiene type of chemisorbed structures with two C—Si bonds at C atoms 1 and 4 have been calculated. Generally, the calculated binding energy increases with the size of the halogen atom, in the series F, Cl, Br, and I. The sp² carbon positions are the most favorable for the halogen atom, and for bromobenzene and iodobenzene there is significant additional stabilization for the geometry that allows interaction of the halogen atom with a nearby Si adatom. This stabilization hinders the transfer of the heavier halogen atoms, Br and I, to the surface. Other chemisorbed structures, involving formally divalent halogen atoms in a C-X-Si type of binding, have also been found to correspond to energy minima in the AM1 calculations. Furthermore, it was possible to calculate physisorbed structures for chlorobenzene and bromobenzene once the Si rest atoms were capped with H atoms. Two types of binding structures are suggested for chemisorption in excess of three molecules per half-unit cell: one is a radical structure binding by a single C-Si adatom bond, and the second one is binding by a single C-X-Si adatom interaction. Both of these singly-bonded structures have been calculated to correspond to energy minima with binding energies smaller than the 1,4-cyclohexadiene type of chemisorbed structure.     

拟除虫菊酯农药手性分离的研究进展

拟除虫菊酯是一类具有光学活性的农业和卫生杀虫剂品种,综述了近年来用液相色谱、气相色谱和电泳等色谱方法对拟除虫菊酯农药进行手性分离的研究进展,并展望了该领域未来的发展趋势。引用文献41篇。     

酶催化卤化和去卤化反应

通过研究微生物降解卤素化合物发现了不同种类的去卤化酶,这些酶可以在好氧或厌氧条件下通过不同的作用机理脱去卤原子催化降解卤素化合物。到目前,通过生物法得到将近4000多种卤素化合物,早期仅分离并获得了催化卤化反应的卤过氧化物酶,近来,在研究细菌卤化代谢物的生物合成时发现了以FADH2为辅基的卤化酶。这种新型的卤化酶在卤化代谢物的生物合成中起催化作用。     

Solid-phase extraction materials based on molecularly imprinted polymers for recognition of pyrethroids

A novel recognition material for detection of kinds of pyrethroids was successfully synthesized by molecular imprinting technology. 3-Phenoxybenzoic acid (PBA) usually could be the antigen to prepare the polyclonal antibody. In this work, the recognition material was prepared utilizing PBA as the template, methacrylicacid as the functional monomer and ethylene glycol dimethacrylate as the crosslinker. The recognition material was characterized by atomic force microscope, adsorption equilibrium and selectivity experiments. The results showed that the recognition material has been successfully prepared and recognized four pyrethroids (fenpropathrin, deltamethrin, fenvalerate, and cyhalothrin). The recognition material was utilized as sorbents in solid-phase extraction for separation and detection of pyrethroids in practically samples. Under the optimal conditions, the recoveries were ranging from 74.3 to 111.0%. Therefore, novel materials for pyrethroids are very promising for future applications. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48919.     

混合含氟甲苄醇类菊酯的结构与杀虫活性关系

报道了混合含氟甲苄醇类菊酯对库蚊和家蝇的生物测试。其结果表明该类化合物对测试害虫显示出较高的杀虫活性和较低的抗性比。在抗性品系中，混合含氟甲苄醇类菊酯表现出比单一异构体和氯氰菊酯更高的活性。     

Platinum sulfated zirconia catalysts. Fate of chlorine during activation

The gases evolved during activation of a sulfated zirconia prepared by impregnation with chloroplatinic acid have been followed using mass spectrometry and infrared spectrometry. When the sample is heated in either helium or in air, the halogen is lost from the catalyst as HCl and Cl2. Heating the sample in hydrogen results in the loss of the halogen as HCl, and only traces as Cl2. The loss of halogen occurs over a wide temperature range (200-900°C). The data are consistent with the chloroplatinic acid being converted by loss of halide with the formation of Pt⁰. This revised version was published online in July 2006 with corrections to the Cover Date.     

具有光学活性的拟除虫菊酯杀虫剂开发概况

在拟除虫菊酯杀虫剂中,越来赵多光学活性产品进入工业化生产。本文主要结合国内拟除虫菊酯市场,按环丙烷羟酸、卤代（或取代）环丙烷羧酸和非环丙烷羧酸三个系列,叙述了光学活性产品的开发概况。     

硼酸锌在聚丙烯(PP)中阻燃效果的研究

本文研究了硼酸锌分别在有卤和无卤阻燃PP材料中协同作用,对不同添加量的阻燃聚丙烯进行物理机械性能及阻燃性能的检测分析,结果表明:硼酸锌的加入可明显提高PP的阻燃性能:在含卤阻燃PP材料中添加硼酸锌,可有效改善阻燃体系的抑烟性,在无卤阻燃PP体系中可显著提高材料的阻燃性,降低阻燃剂的使用量,改善材料的力学性能。