气相色谱法测定噻虫嗪根区施药后在豇豆中的残留

本文主要研究噻虫嗪通过根区施药后,气相色谱测定豇豆植株不同部位的噻虫嗪的残留情况。试验结果显示,0.05、0.10和0.20 kg ai/ha的噻虫嗪根区施药后1-3天,植株中噻虫嗪的残留量慢慢增加,然后随着时间的延长,噻虫嗪的含量开始降低,而且叶片对噻虫嗪的吸收量远远高于茎杆。这些结果表明噻虫嗪不仅可以被植株吸收运输,而且明确了噻虫嗪主要被豇豆叶片吸收储藏。同时也为大田环境中,噻虫嗪施药技术防治害虫提供理论参考。     

70%噻虫嗪种子处理可分散粉剂不同药种比拌种对油菜生长指标的影响

正噻虫嗪是一种全新结构的第二代烟碱类高效低毒杀虫剂,对害虫具有胃毒、触杀及内吸活性,可用于叶面喷雾及土壤灌根处理。其施药后迅速被内吸,并传导到植株各部位,对刺吸式害虫如蚜虫、飞虱、叶蝉、粉虱等有良好的防效。依照噻虫嗪的良好作用机理以及广谱的作用效果,我们针对噻虫嗪以及油菜病虫害的情况,选择70%噻虫嗪种子处理可分散粉剂(WS)对油菜进行     

噻虫嗪在油菜田中的残留规律及风险评估

为探讨噻虫嗪在油菜上使用的安全性,笔者建立了噻虫嗪及其代谢产物噻虫胺在油菜各部位和土壤中的分析方法,开展了噻虫嗪在江苏、湖南和青海三地油菜田中的残留规律研究,评估了噻虫嗪对非靶标生物的环境风险。结果表明,噻虫嗪在油菜各基质中的残留动态均符合一级动力学方程,相关系数均在0.75以上,半衰期为0.91～5.25 d。噻虫胺的主要生成部位是油菜的花序和叶片,并呈现先增多后减少的规律。最终残留试验结果表明,三地油菜籽中噻虫嗪和噻虫胺的最终残留量均小于或等于0.010 mg/kg,低于最大残留限量(MRL),符合食品安全国家标准。环境风险评估的结果表明,噻虫嗪对蚯蚓的急性风险以及鸟类的急性风险和短期风险均可接受,但对鸟类有一定的长期风险。相关研究结果为噻虫嗪在油菜上的合理用药提供了数据支撑。     

虫螨腈和噻虫嗪在芦笋中的残留消解及膳食摄入风险评估

[目的]评估虫螨腈和噻虫嗪在芦笋中的残留对人体的膳食摄入风险。[方法]通过规范田间残留试验,检测芦笋中虫螨腈、溴代吡咯腈、噻虫嗪和噻虫胺的残留量,结合药剂每日允许摄入量和膳食消费量数据,评估虫螨腈和噻虫嗪的长期膳食摄入风险。[结果]虫螨腈和噻虫嗪分别按照180、150 g a.i./hm2用量,喷雾施药1次,施药后间隔3 d采集的芦笋样品中虫螨腈、噻虫嗪和噻虫胺残留量最大值分别为0.14、0.053、0.02 mg/kg,均低于日本制定的芦笋中虫螨腈、噻虫嗪和噻虫胺的最大残留限量(0.5、0.1、0.7 mg/kg)。膳食风险评估表明:虫螨腈、噻虫嗪和噻虫胺在芦笋中的长期膳食摄入风险商分别为0.66、0.13、0.077,均低于1。[结论]按照推荐剂量使用,虫螨腈和噻虫嗪在芦笋中残留不会对我国人体健康产生影响。     

3-甲基4-硝基亚氨基全氢-1，3，5，噁二嗪

1、成果内容简介 3-甲基-4-硝基亚胺基全氢-，3，5-噁二嗪（以下简称噁二嗪）是山东省农药研究所于2006年完成的山东省科技厅计划项目，是新烟碱类杀虫剂噻虫嗪、噻虫胺等的重要中间体。噻虫嗪具有触杀、胃毒和内吸活性，具备许多特点：作用方式新颖、低毒、高效、广谱、持效期长、施药方式广泛、对作物安全性高。噁二嗪的成功开发对于噻虫嗪和噻虫胺的研究，具有重要意义。     

害虫对噻虫嗪抗药性及其治理

噻虫嗪是一种新型的高效新烟碱类杀虫剂,对同翅目（蚜虫、粉虱、飞虱等刺吸式口器害虫）、部分鞘翅目（马铃薯甲虫）和鳞翅目害虫及其对其他种类药剂产生抗性的害虫种群具有优异的防效。化学药剂的大量不合理使用是导致害虫产生抗药性的主要原因。本文简要综述了害虫对噻虫嗪的抗性发展概况、交互抗性、抗性机理及抗性治理策略。马铃薯甲虫和烟粉虱种群对吡虫啉和噻虫嗪都表现出交互抗性,然而,褐飞虱种群对吡虫啉和噻虫嗪却没有交互抗性。害虫的抗性治理应包括抗性监测、抗性机理研究、合理使用杀虫剂及实行综合治理等。     

噻虫嗪及其代谢物噻虫胺在韭菜和土壤中的残留消解动态及残留量

为评价噻虫嗪在韭菜上使用的安全性,开展噻虫嗪及其代谢物噻虫胺在韭菜和土壤中的残留量与残留消解动态研究。结果表明:在有效成分用量为2 700 g/hm~2时,噻虫嗪在韭菜和土壤中的半衰期分别为8.6~11.0 d和8.8~11.4 d。在噻虫嗪有效成分用量为1 800~2 700 g/hm2时,药后7~21 d,韭菜中噻虫嗪和噻虫胺的残留量分别为0.032~3.030 mg/kg和0.027~1.590 mg/kg,土壤中噻虫嗪和噻虫胺的残留量分别为0.174~3.400 mg/kg和0.011~0.193 mg/kg。     

4种杀虫剂对意大利蜜蜂的急性毒性评价

为评价常用杀虫剂对意大利蜜蜂的急性毒性,采用摄入法和触杀法测定了4种杀虫剂对蜜蜂的急性经口毒性和接触毒性。结果表明：4种杀虫药剂对蜜蜂的经口毒性大小顺序为茚虫威〈啶虫脒〈噻虫嗪〈甲维盐,其中茚虫威对蜜蜂的摄入毒性为中毒,啶虫脒为高毒,甲维盐和噻虫嗪为剧毒;接触毒性大小为甲维盐〈啶虫脒〈茚虫威〈噻虫嗪,其中茚虫威、啶虫脒和甲维盐对蜜蜂的接触毒性为高毒,噻虫嗪为剧毒。     

噻虫嗪等杀虫剂对紫花苜蓿叶蝉田间药效分析

[目的]筛选出几种防治苜蓿叶蝉高效、低毒、低残留的杀虫剂及经济有效的使用剂量。[方法]以噻虫嗪等4种药剂,每药剂3个剂量进行田间药效对比试验。[结果]噻虫嗪、啶虫脒、溴氰菊酯等3种杀虫剂对苜蓿叶蝉初始防效高,持效好。[结论]噻虫嗪田间推荐使用剂量为62.5~83.3 mg/L,啶虫脒田间推荐使用剂量为50~66.7 mg/L,溴氰菊酯田间推荐使用剂量为8.3~12.5 mg/L。     

高效液相色谱法测定1%二嗪磷·噻虫嗪颗粒剂

采用高效液相色谱法,以甲醇+水=80+20(V/V)为流动相,使用C18色谱柱,在220nm波长下对1%二嗪磷·噻虫嗪颗粒剂样品中的噻虫嗪和二嗪磷进行分离和定量分析。结果表明:噻虫嗪和二嗪磷的线性相关系数分别为0.9994、0.9997;标准偏差分别为0.49%、0.34%;变异系数分别为2.36%、0.42%;平均回收率分别为99.73%、99.84%。该方法操作简单、快速、准确,适用于1%二嗪磷·噻虫嗪颗粒剂样品的定性和定量分析。     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Novel polyurethane coating technology through glycidyl carbamate chemistry

Glycidyl carbamate chemistry combines the excellent properties of polyurethanes with the crosslinking chemistry of epoxy resins. Glycidyl carbamate functional oligomers were synthesized by the reaction of polyfunctional isocyanate oligomers and glycidol. The oligomers were formulated into coatings with several amine functional crosslinkers at varying stoichiometric ratios and cured at different temperatures. Properties such as solvent resistance, hardness, and impact resistance were dependent on the composition and cure conditions. Most coatings had an excellent combination of properties. Studies were carried out to determine the kinetics of the curing reaction of the glycidyl carbamate functional oligomers with multifunctional and model amines. Detailed kinetic analysis of the curing reactions was also undertaken. The results indicated that the glycidyl carbamate functional group is more reactive than a glycidyl ether group. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, on October 27–29, 2004, in Chicago, IL.     

Highly moisture-proof polysilsesquioxane coating prepared via facile sol-gel process

A highly moisture-proof polysilsesquioxane coating was obtained from a new bis-silylated precursor, which was synthesized from 3-aminopropyltriethoxysilane (APTES) and m-xylylene diisocyanate (m-XDI) in tetrahydrofuran (THF) and verified by ¹H MAS NMR. For direct comparison purposes, an SiO₂ coating was also prepared by the Stöber method using tetraethoxysilane (TEOS) as the reactant. Interestingly, the coating obtained from the polysilsesquioxane sol exhibited a much higher moisture resistance capability than its counterpart, which was attributed to its more compact feature between nanoparticles as characterized by N₂ absorption experiment and transmission electron microscopy (TEM). Furthermore, its high transparency of about 92% showed potential for application in the protection of optical crystals.