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1.
冯永祥 《粘接》1993,14(2):25-26
介绍了环氧树脂胶灌胶配方,以及提高环氧树脂胶粘接强度、防止和减少气泡、裂纹的工艺方法和措施。  相似文献   

2.
侯瑞祥 《粘接》2004,25(3):46-47
介绍了光学胶接件的几种拆胶方法及其工艺条件。同时建议对采用合成树脂光学胶粘接的光学胶接件,在胶接全过程中应建立严格的检验制度,避免不合格的胶接件流入下道工序,以降低拆胶的困难,并进一步提高光学胶接件的质量。  相似文献   

3.
软包装用聚氨酯胶黏剂发展近况   总被引:1,自引:0,他引:1  
简要介绍了软包装及所用聚氨酯(PU)复膜胶的迅猛发展历程.分别介绍了溶剂PU胶黏剂、醇溶PU胶黏剂、无溶剂PU胶黏剂和水性PU(WPU)胶黏剂的发展概况及其优缺点.随着技术进步和环保意识的增强,PU复膜胶由溶剂型逐步向无溶剂、水性方向发展.还介绍了将丙烯酸酯基团引入WPU主链以降低成本、改进某种性能、引人双键等方面的研...  相似文献   

4.
介绍了中国传统木质家具胶粘剂的分类、制作工艺和性质,并分析了传统家具用胶现状,阐述了榫卯家具用胶未来发展需要注意的问题。  相似文献   

5.
胶层厚度对胶接性能的影响   总被引:2,自引:0,他引:2  
郑瑞琪 《粘接》1990,11(4):33-35
本文介绍了胶层厚度影响胶接接头力学性能、耐久性能的若干现象及作者对这些现象的初步理解。  相似文献   

6.
浅谈国产卷烟系列胶   总被引:2,自引:2,他引:0  
回顾了国产卷烟系列胶的发展历程;介绍了国产卷烟系列胶的现状和存在的几个问题。  相似文献   

7.
介绍了需氧胶的特性、用途及制备方法,并与二代丙烯酸酯胶、厌氧胶作了对比。  相似文献   

8.
本文主要介绍了环氧树脂胶粘剂的持点、环氧胶的组成及其作用、环氧胶的固化机理及改性环氧树脂胶的性能等。  相似文献   

9.
介绍了从两亲聚合物及聚合物胶团的形成、聚合物胶团的加溶作用、聚合物胶团加溶理论等方面对聚合物胶团萃取的研究进展做了综述。同时,介绍了作者提出并研究的聚合物反胶团萃取的特性及影响因素。  相似文献   

10.
木材胶粘剂的研究现状和发展趋势   总被引:2,自引:0,他引:2  
杜郢  高山  代飞  罗贺 《粘接》2009,30(2):68-71
本文综述了木材胶粘剂的国内外现状;论述了各种木材胶的结构及作用机理,结合各胶种的优缺点介绍了其应用情况,重点讨论了水性聚氨酯胶粘剂作为木材胶的特点及优势:指出了我国木材加工领域用胶存在的问题和发展趋势。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

18.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

19.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

20.
Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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