流体辅助塑料成型新技术

介绍了近年来气体辅助及其他介质辅助塑料成型的一些新技术,包括振动气体辅助成型技术、多腔控制气辅成型技术、气体辅助共注成型技术、气体辅助挤出成型技术,其他介质成型技术如水辅注射成型技术及液辅成型技术。最后展望了气辅及其他介质成型技术的发展趋势。     

气体辅助注射成型技术与装置

本文介绍了气体辅助注射成型技术的发展史、特性及装置的构成。阐述了气体辅助注射成型的工艺过程及应用该技术的关键,井以实例说明了气体辅助注射成型的优越性。     

气体辅助注射成型技术原理及应用

本文详细介绍了气体辅助注射成型技术的工艺过程与装备，分析了气体辅助注射成型的特点和应用，并对气体辅助注射成型CAE技术作了简要说明。     

气体辅助注射成型在彩电机壳成型上的应用

介绍了气体辅助注射成型技术的工作原理,康佳彩电机壳应用气体辅助注射成型的设备及工艺.此工艺的普及正激励着设计和成型方面令人兴奋的创新和注射原理持续不断的变革,对于塑料制品注射成型行业积极采用气体辅助注射成型新技术有一定的推动作用.     

注射成型技术研究进展

简要介绍了注塑机的发展过程、结构和特点,重点介绍了反应注射成型、气体辅助注射成型、水辅助注射成型、动态注射成型等几种新型注射成型工艺的原理、特点及应用。最后展望注塑机和塑料注射成型技术的发展。     

气体辅助注射成型模拟的数学描述及常用模拟软件概述

首先介绍了建立气体辅助注射成型数学模型的基本思想和成型过程中流体运动基本定律的数学描述,然后介绍了气体辅助注射成型模拟的基本流程和目前市面上常用气体辅助注射成型数值模拟软件。     

快速发展的水辅助注射成型技术

介绍水辅助注射成型技术的原理、应用和发展 ,并与密切相关的气体辅助注射成型作了比较     

气体辅助注射成型技术

介绍了消除厚壁制件所出现的缩痕、凹痕缺陷的一种新型塑料成型工艺－－气体辅助注射成型技术的工作原理,技术关键、设备配置及其应用,并重点介绍了内置气体辅助成型和表面气体辅助成型技术。     

气辅注塑成型工艺过程及其关键技术

气体辅助注塑成型工艺包含塑料熔体注射和气体注射两部分,由气体推动塑料熔体充满模具型腔,因此具有普通注塑成型工艺所没有的优点,但在应用上也带来了特殊的技术要求。本文介绍了几种常用的气体辅助注塑成型工艺过程,并从制品设计、模具技术和工艺控制三方面分析了应用气体辅助注塑成型工艺的关键技术。     

气体辅助注射成型技术及其制品设计

介绍了气体辅助注射成型技术和气体辅助注射成型的制品设计。     

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.     

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.     

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.     

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.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。