聚二烯丙基二甲基氯化铵-丙烯酰胺-丙烯酸的制备与表征

以丙烯酸(AA)、丙烯酰胺(AM)用量和体系pH等作为考察因素,以聚合物配合质量分数为2%铬粉应用于皮革鞣制工艺的应用效果为指标,对聚二烯丙基二甲基氯化铵-丙烯酰胺-丙烯酸(PDM-AM-AA)的制备条件进行了优化.结果表明:当n(DM):n(AM):n(AA)=1:2:3,体系pH=5.5时,聚合物产率达94.53%,配合质量分数为2%铬粉应用于皮革鞣制工艺效果较好.对所制备产物的结构采用红外光谱、X射线衍射和差示扫描量热进行了表征,表征结果表明三种单体成功发生了聚合.     

新型超高相对分子质量两性聚丙烯酰胺的合成

以丙烯酰胺(AM)、二甲基二烯丙基氯化铵(DMDAAC)及顺丁烯二酸(MA)为聚合单体,偶氮二异丁咪唑啉盐酸盐为引发剂,采用水溶液聚合法合成了超高相对分子质量两性聚丙烯酰胺(APAM),研究了单体浓度、单体摩尔比、引发剂用量、聚合温度以及反应体系pH值对聚合的影响,并通过傅里叶变换红外光谱仪对APAM结构进行了表征。结果表明:当总单体质量分数为20%,n(AM)/n(DMDAAC)/n(MA)为10∶80∶10,引发剂质量分数为0.05%,温度为50℃,反应体系pH值为7时,APAM的相对分子质量最高达到4.28×107。当用于处理模拟废水时,在pH值为3~10的环境中,APAM均能产生絮凝效果,说明产品适应的pH值范围较宽。     

AM/DMDAAC/AA型两性聚丙烯酰胺的制备及应用研究

以丙烯酰胺(AM)、二甲基二烯丙基氯化铵(DMDAAC)、丙烯酸(AA)为单体,用溶液共聚法制备两性聚丙烯酰胺(AMPAM),研究了反应条件对两性聚丙烯酰胺分子量及絮凝性能的影响。结果表明,采用K2S2O8-NaHSO3(质量比1∶1)氧化还原复合引发体系,引发剂用量为0.88%,单体用量为24.5%,聚合温度为55℃,溶液pH值为6,单体摩尔比为n(AM)∶n(DMDAAC)∶n(AA)=1∶0.3∶0.5,聚合时间为4 h,得到的产品综合性能最佳,且具有良好的絮凝脱色效果。     

阳离子聚丙烯酰胺P(AM-DMDAAC)的合成与应用研究

该文以二甲基二烯丙基氯化铵(DMDAAC)、丙烯酰胺(AM)为单体,在光引发剂作用下,通过水溶液共聚法合成阳离子型聚丙烯酰胺(CPAM)。采用单因素优化实验,研究了单体配比、单体质量分数、引发剂用量、反应温度及尿素添加量等因素的影响。得到最优制备条件:摩尔比为n(AM)∶n(DMDAAC)=1∶0.18,单体质量分数为25%,引发剂用量为0.02%,聚合温度为30℃,尿素添加量为4%,产物特性黏数最高为934 m L/g。通过红外光谱表征,产品与CPAM特征基团相符合,絮凝实验表明其具有良好的絮凝效果。     

新型酸液稠化剂的制备与性能评价

酸化处理是油气井增产增注的重要措施之一,而其中稠化剂是酸液中一种重要的酸性添加剂.文章中以二甲基二烯丙基氯化铵（DMDAAC）和丙烯酰胺（AM）为原料,过硫酸铵-亚硫酸氢钠为引发剂,采用水溶液聚合制备共聚物PDA（（Poly DMDAAC-AM）.实验考察了单体配比、总单体质量分数和引发剂用量等反应条件对共聚物特性粘数和单体转化率的影响.结果表明,经红外检测AM和DMDAAC发生了聚合,单体配比n（AM）∶n（DMDAAC）=8∶2,单体总质量分数为20％,引发剂用量为过硫酸铵和亚硫酸氢钠各占单体总质量的0.04％,最高单体转化率为67.70％,最佳特性粘数为505.59 mL/g.实验采用石油工业标准（SY/T6214-1996）对产品性能进行了评价,结果表明产品性能优良,可用作酸液稠化剂.     

新型网状超高分子量阳离子聚丙烯酰胺的合成

以丙烯酰胺(AM)和二甲基二烯丙基氯化铵(DMDAAC)为聚合单体,N,N'-亚甲基双丙烯酰胺(MBA)为交联剂,偶氮二异丁咪唑啉盐酸盐(VA-044)为引发剂,采用水溶液聚合法合成了标题化合物,考察了单体物质的量比、引发剂用量、交联剂用量、聚合温度、pH以及单体浓度对聚合反应的影响。研究表明,当单体物质的量比n(丙烯酰胺)∶n(阳离子单体)=8∶2,引发剂用量为0.05 wt%,交联剂用量为0.000 5 wt%,温度50℃,pH为6,单体浓度为20 wt%时,分子量最高达到4.25×107g/mol,并通过傅里叶变换红外光谱仪对其结构进行了表征。用所合成的聚丙烯酰胺处理模拟废水,当其投料量为8 g/mol时,上层清液透光率能达到92%。     

页岩气压裂用抗盐速溶滑溜水降阻剂的制备及性能评价

以丙烯酰胺(AM)和二甲基二烯丙基氯化铵(DADMAC)为聚合单体,自制聚甲基丙烯酰氧乙基三甲基氯化铵(P-DMC)为分散剂,水溶性偶氮二异丁脒盐酸盐(V-50)为引发剂,以乙醇-水体系为分散介质,采用分散聚合法合成了阳离子型聚丙烯酰胺乳液降阻剂。通过单因素实验确定了共聚物合成的较佳条件:单体配比n(AM)∶n(DADMAC)=6∶1,单体加量占聚合体系总质量的40%(w),分散剂加量对单体总质量占比为8%(w),分散介质m(乙醇)∶m(水)=50%,引发剂加量对单体总质量占比为0.2%(w),聚合温度60℃,反应时长8 h。结果表明,合成产物稳定性良好,分子量达1.26×10⁶,在矿化度为30 000 mg/L的模拟水中黏度保持率达78.6%,质量分数0.2%的聚合物溶液降阻率最高可达66.4%,可在10 min内完全溶解,在页岩气井压裂开采过程中具有广阔的应用前景。     

光引发合成两性离子型聚丙烯酰胺的工艺优化

以丙烯酰胺(AM)、阴离子单体丙烯酸钠(AANa)和阳离子单体二甲基二烯丙基氯化铵(DMDAAC)为原料,采用光引发聚合方式合成了两性离子型聚丙烯酰胺P(AM-DMDAAC-AANa);探讨了合成P(AM-DMDAAC-AANa)的最佳条件。结果表明:在n(AM)∶n(AANa)∶n(DMDAAC)=1∶0.65∶0.16,单体质量分数为32%,引发剂用量为0.08%,光照时间为2.5 h,反应温度为30℃,p H=6.5的条件下,得到产物的特性黏数为887 m L/g。红外光谱分析表明:所得产物符合P(AM-DMDAAC-AANa)的结构特征。     

页岩气压裂用抗盐速溶滑溜水降阻剂的制备及性能评价

以丙烯酰胺(AM)和二甲基二烯丙基氯化铵(DADMAC)为聚合单体,自制聚甲基丙烯酰氧乙基三甲基氯化铵(P-DMC)为分散剂,水溶性偶氮二异丁脒盐酸盐(V-50)为引发剂,以乙醇-水体系为分散介质,采用分散聚合法合成了阳离子型聚丙烯酰胺乳液降阻剂。通过单因素实验确定了共聚物合成的较佳条件:单体配比n(AM)∶n(DADMAC)=6∶1,单体加量占聚合体系总质量的40%(w),分散剂加量对单体总质量占比为8%(w),分散介质m(乙醇)∶m(水)=50%,引发剂加量对单体总质量占比为0.2%(w),聚合温度60℃,反应时长8 h。结果表明,合成产物稳定性良好,分子量达1.26×10~6,在矿化度为30 000 mg/L的模拟水中黏度保持率达78.6%,质量分数0.2%的聚合物溶液降阻率最高可达66.4%,可在10 min内完全溶解,在页岩气井压裂开采过程中具有广阔的应用前景。     

响应曲面优化法合成聚丙烯酰胺类共聚物

采用响应曲面优化法(Response surface methodology)以丙烯酰胺(AM)和二甲基二烯丙基氯化铵(DMDAAC)为共聚单体,通过自由基聚合对聚丙烯酰胺类共聚物(PDA)进行制备研究。探讨了3个主要因子单体摩尔比、聚合体系p H、引发剂用量的最佳水平及各自变量间的交互作用对PDA得率的影响,通过该法设计得到了最佳优化条件:单体摩尔比n(AM)∶n(DMDAAC)=2.5∶1,聚合体系p H6.00,引发剂用量为单体总质量的1.00%。在模型提供的最优水平下PDA得率89.807%,与预测值91.6944%相吻合,表明所选模型准确、可靠。该方法为聚丙烯酰胺类共聚物的合成及应用提供了依据。     

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。     

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.