篱栏网多糖的提取工艺优化及抗氧化活性

优化了热水浸提法提取篱栏网多糖的工艺,最佳条件为:液料比26 mL/g,温度94.5℃,提取时间3.6 h,提取次数2次,此时多糖提取率为(4.38±0.04)%;该多糖清除DPPH自由基的IC_(50)值为(0.12±0.03)mg/mL,清除羟基自由基的IC_(50)值为(1.21±0.02)mg/mL。     

硫酸浓度计和酸浓自控

电导式硫酸浓度计 一、98％硫酸浓度计 (1)仪表的主要技术要求 测量范围:96～99％H_2SO_4,分度值0.1％H_2SO_4 测量误差:±0.1％H_2SO_4 酸温变化范围:50～70℃ (2)仪表的工作原理 在96～99％H_2SO_4范围内,酸温为50～70℃,硫酸的浓度与其电导率之间有单值的关系。     

候选农药病氰硝水解和光解的特性

[方法]采用室内模拟方法研究了病氰硝在水环境中的动力学规律,考察病氰硝的光降解受pH值的影响以及水化学降解受pH值和温度的影响.[结果]在光解条件下的半衰期t1/2分别为5 h[pH值5,(25±1)℃]、1.6 h[pH值7,(25±1)℃]、1.4 h[pH值9,(25±1)℃]；该农药的水解半衰期t1/2分别为3.9 d[pH值7,(25±1)℃]、31.4 d[pH值9,(25±1)℃]、6.9 d[pH值7,(37±1)℃]、17.3 d[pH值9,(37±1)℃]、8.7 d[pH值7,(50±1)℃]、4.6 d[pH值9,(50±1)℃],在pH值5的缓冲溶液中较稳定.[结论]按《化学农药环境安全评价试验准则》规定,病氰硝属于易光解,在中性和碱性条件下易水解类农药.     

活性纳米碳酸钙的pH值测试

采用电位计法比较了活性纳米碳酸钙pH值测试过程中过滤、暴露时间、乙醇浸润量、温度、回旋振荡时间等对活性纳米碳酸钙pH值测试结果的影响。较佳的测试条件为:取(10±0.01)g活性纳米碳酸钙经乙醇浸润,加入100 m L无CO_2的水,在(50±1)℃下回旋振荡30 min,待悬浮液冷却至(25±1)℃,过滤,测试滤液的pH值。     

球孢白僵菌Bb080920菌株对番石榴实蝇的毒力测定

[目的]筛选出防治番石榴实蝇Beauveria bassiana(Bezzi)的有效生防菌。[方法]分别采用喷雾法和浸渍法测定不同浓度的球孢白僵菌Bb080920分生孢子液对番石榴实蝇成虫、幼虫和蛹的室内毒力。[结果]成虫的最大校正死亡率达(91.83±2.42)%,致死中浓度(LC50值)为(2.6281±0.2362)×108个/L,致死中时间(LT50值)为(4.61±0.37)d;幼虫最大累计校正死亡率达(95.23±3.13)%,LC50值为(2.5416±0.8395)×108个/L,LT50值为(4.36±0.42)d;蛹的累计校正死亡率最大达(82.59±2.78)%,LC50值为(2.7692±0.1538)×108个/L,LT50值为(5.05±0.68)d。[结论]球孢白僵菌Bb080920菌株毒力测定表明具有很高的毒性,未来有良好的应用前景。     

二氰蒽醌的水解、光解和挥发性

为研究二氰蒽醌的水解、光解和挥发3种环境行为特性,采用室内模拟实验方法,测定二氰蒽醌的水解性、光解性和挥发性,并对此3种特性分别进行评价.结果表明:二氰蒽醌的水解半衰期t1/2为42.5 d[pH值5,(25±1)℃]、84.5 h[pH值7,(25±1)℃]、19.3 h[pH值5,(50±1)℃]、85.6 min[pH值7,(50±1)℃],在pH值9缓冲液中迅速水解而无法测定其半衰期;该农药在纯水中光解t1/2为52.1 min(平均光强为4313 1x,平均紫外强度为92.3μw/cm2);其挥发性表现为在空气、水和云南黏土表面3种介质中均未有挥发.按<化学农药环境安全评价试验准则>规定,二氰蒽醌水解性为较易水解和易水解,在纯水中光解特性为易光解,在空气、水和云南黏土表面挥发性属难挥发.     

ECDP短纤维染色饱和值的测定

以亚甲基蓝染料对阳离子染料可染涤纶(ECDP)短纤维进行染色,讨论了在ECDP短纤维染色过程中,染浴的pH值、染色温度、保温时间、染料浓度等因素对纤维染色饱和值(Sf)的影响。结果表明:染浴的pH值控制在4.5～5.0,纤维入染温度为50℃,以2℃/min的速率升到80℃,再以0.5℃/min的速率升到100℃,在100℃时保温时间为120 min;染料相对纤维的质量分数为5%～9%时,测得ECDP短纤维的Sf为8.4。     

硫化机外温控制改造

硫化机是轮胎生产最后工序的关键设备,我公司工艺要求硫化机外温应控制在(151±2)℃。针对定时器控制外温存在升温慢且温度波动大的问题,改用保温式控制外温,取得了满意的效果。1改造前设备状况我公司早期购买的1613和1651mm硫化机有16台福建三明硫化机厂产品,外温及外压均采用PID控制外压进和外压排调节阀调节。由于PID调节反应速度慢,因此外压进调节阀的开度平均为80%以上,外压排调节阀近似全开,升温速度慢且浪费大量蒸汽。为节能降耗,借鉴三明硫化机外温控制新方法,采用定时器控制外压排。使用定时器控制的外压排方案如下。(1)将硫化…     

袁河新余市区段水中COD_(Mn)的测定与分析

通过优选优化水中CODMn的测定方法与条件,得到了适合本地段水质测定的方法是酸性高锰酸钾法,其适宜的测定条件为:(1)样品处理应在采集后2 h内加入硫酸调pH2,且尽快检测;必要时应保存在0~5℃冷藏,并在48 h内完成测定。(2)KMnO4标准溶液和Na2C2O4标准溶液的浓度应在0.0095~0.0105 mol/L内。(3)应在沸水浴中加热,加热时间应从水浴沸腾时计,并控制为30±1 min。(4)加入(1+3)H2SO4的体积为水样体积的5%。(5)应调控K值为0.85~0.95。(6)滴定时,起滴温度应控制在85±3℃,滴定结束时,滴定体系温度不低于65℃。(7)滴定应在2±0.5 min内完成。(8)用光度滴定或电位滴定法确定终点。从测定结果可知袁河新余市区段水中CODMn值从2002年以来是呈总体逐年向好方向发展,但不同年份、不同取样点和不同季节下所测得的CODMn值绝大多数达不到GB 3838-2002的Ⅱ类水质标准,个别甚至为劣于Ⅴ类的水;文章分析了导致此现状的原因,并对存在的问题提出了一些解决对策。     

用铜盐比色法测定亚胺硫磷含量的两点意见

一、温度高能引起铜络合物消光值降低。我们用不同温度的比色皿(2公分)装同一铜盐络合物测定消光值如下: 比色皿温度装入络合物液温消光值 37℃ 35℃ 30.5E 32℃ 32.5℃ 32E 按部标准规定:吸取样品液Ⅱ10毫升,加入0.1 N盐酸液70毫升,而游离硫化物是吸取50毫升样品液Ⅱ加入事先中和0.2N盐酸30毫     

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.     

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.     

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。