高效液相色谱法研究饲料金霉素中金霉素和四环素含量的分别测定

本文提出了以稀ＨＣｌ直接提取饲料金霉素中金霉素和四环素，提取液无需净化，用二甲基甲酰胺——草酸溶液作流动相，以高效液相色谱紫外检测器测定饲料中金霉素和四环素的含量。结果表明该法快速、准确、简便、可靠；方法回收率四环素和金霉素分别在９１．８４～１０４．１％ 和８８．９２～１０４．６％ 之间；变异系数分别为４．７４％ 和５．４０％ ，该法国内外未见报导。     

耐浓硫酸腐蚀新型铸造合金的研究

本文设计了新型铸造合金的化学成份：Ｃ≤０．０３；Ｓｉ４．０％～５．０％，Ｍｎ≤１．０％，Ｐ，Ｓ≤０．０３％，Ｃｒ２４．０％～２６．０％，Ｎｉ２９．０％～３１．０％，Ｍｏ２．０％～４．０％；Ｃｕ１．５％～７．５％，Ｆｅ为余量。通过Ｘ射线衍射，均匀腐蚀，点腐蚀，晶间腐蚀实验，研究了该合金的显微组织及其腐蚀行为。试验结果表明，通过Ｃｒ，Ｎｉ，Ｓｉ，Ｍｏ，Ｃｕ多元合金化的新型铸造合金，经１２００℃，２ｈ水     

MgCl_2对黑曲霉柠檬酸发酵影响

黑曲霉（Ａｓｐｅｒｇｉｌｕｓ．ｎｉｇｅｒ）柠檬酸发酵培养基中添加０．０８～０．１５ｍｇ／Ｌ的ＭｇＣｌ２,对菌体浓度没显著性影响,但可使柠檬酸产率提高４％～７％,发酵旺盛期（３０ｈ）断氧３０ｍｉｎ的实验结果与正常发酵结果对照表明：添加０．１ｍｇ／ＬＭｇＣｌ２的摇瓶产酸率下降１６．２％;空白对照摇瓶产酸率则下降５６．８％,通过对柠檬酸合成酶［ＥＣ４．１．３．７］酶活测定及活体染色计数,我们认为,断氧条件下,０．１ｍｇ／ＬＭｇＣｌ２使黑曲霉存活率升高是造成上述差异的主要原因。     

宇佐美曲霉酸性蛋白酶发酵工艺研究

宇佐美曲霉Ｌ３３５是一株分泌高单位酸性蛋白酶的产生菌,本研究采用单因素搜索和正交试验,通过摇瓶发酵和２Ｌ搅拌罐发酵,对其发酵工艺进行优化。结果表明,较适宜的发酵培养基（ｇ／１００ｍＬ）为黄豆粉５．０、玉米粉１．２、鱼粉０．８、ＣａＣｌ２ ０．５、Ｎａ２ＨＰＯ４ ０．２、ＮＨ４Ｃｌ１．０、蚕蛹水解液１０．０;通气量控制２５ｈ前为１：０．４ｖ／ｖ／ｍ、２５－５０ｈ１：１．０ｖ／ｖ／ｍ,５０ｈ后１：３ｖ     

耐硫酸及其盐腐蚀的新型双相不锈钢的研究

针对含Ｈ２ＳＯ４１１０．５ｇ／Ｌ、Ｎａ２ＳＯ４３８７ｇ／Ｌ、ＺｎＳＯ４１４．４ｇ／Ｌ，密度为１．３５ｇ／ｃｍ３，温度为６０℃的介质，设计了泵用不锈钢的金相组织和化学成分。其金相组织确定为奥氏体—铁素体双相不锈钢，化学成分为：Ｃ≤０．４％、Ｓｉ４．０％～５．０％、Ｍｎ≤０．８％、Ｐ，Ｓ≤０．０３％、Ｃｒ１９％～２１％、Ｎｉ１９％～２１％、Ｍｏ２．０％～３．０％、Ｃｕ２．０％～３．０％，其余为Ｆｅ。采用金相显微镜和Ｘ射线衍射的方法观察与分析了钢的金相组织，通过试验测定了耐蚀性能，并与性能优良的９０４和ＣＤ４ＭＣｕ钢进行对比。试验结果表明，经１１００℃固溶处理后的新型双相不锈钢（ＫＳ－５）耐蚀性能明显优于对比合金。     

嘧磺隆的高效液相色谱分析

采用高效液相色谱法，以Ｃ１８柱为分离柱，以甲醇－水－乙酸（６０／４０／０．５）含０．０１ｍｏｌ·１－１醋酸铵为流动相，内标法测定嘧磺隆的含量，９次测定结果，其平均值为８９．１４％，标准偏差为０．３９％，变异系数为０．５４％，回收率为９９．６％～１０１．４％。     

甲基丙烯酸氧化制甲基丙烯酸催化剂的研究

本文对甲基丙烯酸氧化制甲基丙烯酸催化剂进行了研究．对催化剂组成中Ｋ、Ｃｓ、Ｒｂ、Ｔｌ、Ｂ、Ｍｏ含量对催化剂活性的影响分别进行了考察．催化剂活性评价表明，当催化剂组成ＭｏａＰｂＶｃＣｕｄＡｓｅＺｆｏｘ的ａ＝８～１５、ｂ＝０．５～２、Ｃ＝０．０８～０．４、ｄ＝０．０５～０．３、ｅ＝０．１～１、ｆ＝０．１、ｚ＝Ｋ时活性较好．在反应温度２９０℃，Ｍｏ含量为１０，Ｂ为０．１，Ｋ＝０．０８时，甲基丙烯酸的转化率达９２％以上，甲基丙烯酸收率达７４％．     

世界聚氯乙烯市场现状及预测

１９９１年世界ＰＶＣ生产能力约为２０００万ｔ，预计１９８８～１９９５年生产能力年均增长率为４％，１９９５～２０００年为１．１％，增长减慢；１９８７～１９９０年世界ＰＶＣ硬制品和软制品需求年均增长率分别为４．９％和２．３％，预计１９９３～１９９６年将分别增至６．０％和３％；１９９１年世界ＰＶＣ贸易量为１８５万ｔ，１９９２年为１９３万ｔ。     

美国1993年合纤产量

美国１９９３年合纤产量ＰＥＴ短纤维１０３．９万ｔ（－０．２％），民用长丝为４０．８万ｔ（＋０．１％），工业用丝１７．４万ｔ（＋０．４％）；ＰＡ短纤维４３．０万ｔ（＋２．９％），ＢＣＦ丝４９．６万ｔ（＋７．０％），民用丝１６．７万ｔ（－０．７％），工业...     

T M E D A/ n - Bu Li 体系丁二烯- 苯乙烯溶液共聚的偶联反应(英文)

研究了 Ｔ Ｍ Ｅ Ｄ Ａ 与 Ｓｎ Ｃｌ４ 用量对丁苯共聚偶联反应的影响。结果表明, 取 Ｔ Ｍ Ｅ Ｄ Ａ／ Ｌｉ 为０ ．１ ,当 Ｓｎ Ｃｌ４／ Ｌｉ 为０ ．１３ 时, Ｈ Ｉ达到最大值１ ．７３ ;当 Ｓｎ Ｃｌ４／ Ｌｉ 为０ ．２５ 时, Ｃ Ｅ 达到最大值６８ ．２５ ％ 。取 Ｓｎ Ｃｌ４／ Ｌｉ 为０ ．１３ ,发现 Ｔ Ｍ Ｅ Ｄ Ａ 加入量对 Ｃ Ｅ 及 Ｈ Ｉ 无明显影响。     

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.     

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。     

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.     

基于ATRP法制备的触角状亲水性羟胺树脂的吸硼性能的研究

以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。