分光光度法测定工业碳酸锶中氯化物

采用目视比浊法测定工业碳酸锶中的氯化物，若溶液有色，准确定量非常困难。在溶样时加入氧化剂，利用分光光度计进行比浊。研究了在氧化剂存在下，样品的溶解、过滤对结果的影响，添加氧化剂对体系稳定性的影响，建立了用分光光度计进行比浊测定氯化物的方法，方法具有良好的线性关系，回收率在101％-106％，相对标准偏差在1．15％-3．65％，结果准确、快速，满足了生产对氯化物含量定量的要求。     

离子色谱法测定铁矿石中水溶性氯化物

文章研究了离子色谱法测定铁矿石样品中水溶性氯化物。试样经超声波提取后,采用阴离子分离柱SUPP4-250和MSM（Metrohm Suppressor Module）抑制器,以电导检测器检测,用1．8mmol／LNa2C03和1．7mmol／LNaHCO3混合液作淋洗液,以标准曲线法为定量方法,测定其中的水溶性氯化物。方法检出限为1．7×10^-3mg／L,氯化物含量为0．2569％时,方法的相对标准偏差为0．77％,样品的加标回收率为95．6％～100．1％。该方法操作简单,快速高效,灵敏度高,结果准确、可靠。     

卡尔费休库仑滴定法测定甲烷氯化物中微量水分

本文建立了卡尔费休库仑滴定法测定二氯甲烷和三氯甲烷工业产品中微量水分测定的分析方法，此方法实现了从取样到分析的全封闭操作过程。二氯甲烷和三氯甲烷的加标回收率分别97．5％～106．2％和88．2％～103．1％，RSD分别为5．3％和9．7％。该方法准确、快速、简便，完全能够满足甲醇法生产甲烷氯化物产品中微量水分测试需要。     

光卤石和钡熔剂X—射线荧光光谱分析方法

介绍用溶液滤纸片（ＳＦＰ）制样,以Ｘ—射线荧光（ＸＲＦ）光谱快速测定光卤石、钡熔剂样品中氯化物组分和结晶水等。采用外部通道输入法,使结晶水和水不溶物参与氯化物测定结果共同作归一化（１００％）计算。根据归一化因子（ＮＦ）接近１．００为依据,从而判断测量结果可信与否。本方法简便、快速,准确度能满足生产要求     

分光光度法测定磷矿石中氯化物含量

通过对磷矿石中氯化物含量进行测定研究,结果表明该方法简便,准确,灵敏度高。试样溶液以丙三醇一乙醇作稳定剂,加入硝酸银形成氯化银胶状悬浊液,在40℃水浴中保温25min,采用分光光度计在波长350nm处测定氯化物含量,加标回收率在98．0％～100．3％,RSD为3．6％,该方法具有良好的线性关系。适用于磷矿石中氯化物含量的检测。     

燃烧滴定法快速测定碳酸钡中的硫

采用燃烧滴定法测定碳酸钡中硫含量，并对样品作测定前的预处理。在测定中选用复合型助熔剂，既可使样品高温燃烧，又可避免因氧气流的作用而导致样品喷溅的问题。该方法准确测定硫的质量分数范围0．0001％-10％，回收率95．2％～102．2％，相对标准偏差（RSD）为0．89％～2．31％，操作简单快速，方法准确可靠，满足测定要求。     

酱油中防腐剂山梨酸和苯甲酸的气相色谱快速分析方法

采用毛细管气相色谱外标法测定酱油中防腐剂苯甲酸和山梨酸，样品回收率均在97．4％～103．1％之间，标准线性关系良好，样品测定的相对标准偏差小，苯甲酸为0．53％，山梨酸为1．435％；本方法具有简便、快速、准确的特点。     

离子色谱法测定油基切削液和机床排泄物中亚硝酸根

研究了采用离子色谱测定油基切削液和机床排泄物中亚硝酸根的方法。采用水作为萃取剂萃取切削液及排泄物中亚硝酸根,对萃取条件进行了优化,本方法对亚硝酸根的检出限为0．015mg／L,样品回收率在90．9％-100．9％,相对标准偏差在1．04％～1．76％。     

高频红外吸收法测定水泥中的硫

采用高频红外吸收法测定了水泥中硫的含量，并对样品作测定前的预处理(物理处理)，在测定中选用复合型助熔剂．解决了高频感应炉中顶吹氧气流的作用而导致的样品喷溅问题。该法可准确测定硫含量在0．001％～5％的水泥样中的硫，回收率为98、6％～102．5％，相对标准偏差为0．78％～1．35％。     

电感耦合等离子体发射光谱法同时测定菊花中多种微量元素的研究

研究了用硝酸＋高氯酸消解样品，试液用ICP－AES法同时测定菊花中锌，铁，锰，铜，镁的新方法，在选定的最佳条件下测锌，铁，锰，铜，镁的检出限分别为4．2，18，0．4，7．3，4．8ug.mL^-1，回收率为95．5％－102．8％，RSD为1．3％－3．9％，法准确，快速，简便，应用于菊花样品的测定，结果满意。     

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.     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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。     

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.