α-磺基月桂酸聚氧乙烯醚十八烷基氨基丙酸单酯磺酸盐的合成及性能

以月桂酸、十八胺和聚乙二醇500为原料通过磺化、酯化和酯交换反应合成了非对称两性双子表面活性剂α-磺基月桂酸聚氧乙烯醚十八烷基氨基丙酸单酯磺酸盐(NSG)。通过红外光谱分析确定了产物结构,并对其物化性能进行了测定。结果表明:NSG的γcmc=48.81 mN/m,cmc=0.000 1 mmol/L;即时泡沫高度为30 mm,5 min后为20 mm;润湿时间为19.6 s;乳化时间为24.82 s(甲苯/水)和20.63 s(豆油/水)。     

Guerbet十四醇聚氧乙烯醚硫酸钠的合成与表面活性

以Guerbet十四醇 (C14 GA)为中间体 ,经Williamson反应合成Guerbet十四醇聚氧乙烯醚醇〔C14 GA(EO) nH ,n =1,2 ,4〕 ,再经氯磺酸酯化及NaOH中和 ,得到阴离子表面活性剂Guerbet十四醇聚氧乙烯醚硫酸钠〔C14 GA(EO) nS ,n =1,2 ,4〕。用IR、NMR和元素分析测定了所合成的表面活性剂的结构 ,并利用表面张力法测定了这些表面活性剂水溶液的表面活性。实验结果表明 :所合成的表面活性剂的结构分别为C14 GAEOS (A) ,C14 GA(EO) 2 S(B)和C14 GA(EO) 4 S(C) ;这些表面活性剂其临界胶束浓度CMC(mmol/L) ,在CMC时的表面张力γCMC(mN/m)和Krafft点 (℃ )分别为A :2 5 8mmol/L ,2 7 6mN/m ,5 9℃ ;B :0 80mmol/L ,2 6 4mN/m ,2℃和C :0 12mmol/L ,2 5 3mN/m ,0℃。均比常用的直链阴离子表面活性剂C12 H2 5SO4Na(8.6mmol/L ,4 1 2mN/m ,16℃ )有更低的CMC ,γCMC和Krafft点 ;聚氧乙烯基的引入 ,对降低CMC ,γCMC和Krafft点的效果随氧乙烯基团数目的增多 (由 1增至 4 )而加大。讨论了表面活性剂的结构和表面活性的关系     

双癸基甲基羟乙基氯化铵的合成及其性能研究

以双癸基甲基叔胺(DMA10)、盐酸和环氧乙烷为原料,合成了双癸基甲基羟乙基氯化铵(DMHAC10)阳离子表面活性剂。通过红外光谱对其结构进行了表征,并对其表面活性、泡沫性能、润湿性能和杀菌性能进行了测试。结果表明,其cmc为10.37 mg/L,γcmc为27.35 mN/m;在二次蒸馏水中的即时泡沫高度为190 mm,在150 mg/L(以CaCO3计)的硬水中的即时泡沫高度为189 mm;润湿时间为61 s;在质量浓度为300 mg/L时,对金黄色葡萄球菌(ATCC-6538)和大肠杆菌(ATCC-8099)的杀灭率达100%。     

头基含羟基的季铵盐双子表面活性剂的合成与性能

以溴代烷、二乙醇胺和1,4-二溴丁烷为原料,通过两步反应合成了一类头基含羟基的季铵盐双子表面活性剂亚丁基-1,4-双(烷基二羟乙基溴化铵)(m-4-m(OH),m=8,10,12,14),通过核磁共振氢谱(~1H NMR)和质谱(MS)对中间体和目标产物的结构进行表征。通过表面张力仪和电导率仪测定m-4-m(OH)在水溶液中的平衡表面张力(γ_(cmc))和临界胶束浓度(cmc),并测定了其水溶液的乳化性能和泡沫性能。结果表明,烷基链越长,表面活性剂越容易自发形成胶束,14-4-14(OH)的cmc最低,可达0.48 mmol/L,γ_(cmc)为33.6 mN/m;头基中引入羟基可有效降低表面活性剂的cmc和γ_(cmc);随着烷基链的增长,乳化性能越好;起泡性随着烷基链的增长呈先升后降的趋势。     

乙二醇双硬脂酸酯乙氧基化物的合成与性能研究

以乙二醇双硬脂酸酯为原料,在催化剂作用下直接与环氧乙烷(EO)进行加成反应得到具有反Bola结构的乙二醇双硬脂酸酯乙氧基化物的系列产物,通过红外光谱对产物结构进行了表征,并研究了产物的物化性能。实验结果表明,随着EO加合数的增加,产物的浊点升高;临界胶束浓度(cmc)增大,cmc时的表面张力(γcmc)先降低后升高,最低为33.18 mN·m-1;乳化力先增加后降低;去污力提高,当EO加合数为30时,产物的去污力达到93%;泡沫性能较差,为低泡类表面活性剂。     

AES与AEO_9复配体系表面活性的研究

研究了脂肪醇聚氧乙烯醚硫酸钠(AES)与非离子表面活性剂脂肪醇聚氧乙烯醚9(AEO_9)按不同质量比复配所得表面活性剂体系的临界胶束浓度(cmc)、平衡表面张力(γ)及动态表面张力(DST)。当得到AES-AEO_9复配体系质量比为3∶7时,临界胶束浓度(cmc)最小,为0.10mmol/L,γ_(cmc)为33.62mN/m;质量比为1∶9时动态表面张力最好,此时动态表面张力参数n为1.74,t*为1.32s,表面张力降低速率R_(1/2)为14.30mN/m·s。不同浓度动态表面张力结果表明,随复配体系浓度增加,诱导期节省时间t_i减少,R_(1/2)增加。     

居贝特十四醇聚氧乙烯醚羧酸钠盐的合成及表面性能

以正庚醇为起始原料,经过Guerbet、Williamson等一系列反应合成出了具有支链结构的居贝特十四醇聚氧乙烯醚羧酸钠盐[C14GA(EO)nCH2COONa,n=1-4]。用IR、NMR测定了所合成的表面活性剂的结构;用滴体积法测定了其表面张力。结果表明:该类表面活性剂有比较好的表面性能,并且随着分子中氧乙烯(EO)单元数的增多,该系列表面活性剂[C14GA(EO)nCH2COONa,n=1-4]的临界胶团浓度(CMC)以及临界胶团浓度时的表面张力(γCMC)降低,分别为:10．50 mmol/L,27．87 mN/m;0．85 mmol/L,26．00 mN/m;0．75 mmol／L,25．20 mN/ m:0．59 mmol/L,25．18 mN/m。讨论了该类表面活性剂的结构与表面活性的关系。     

双癸基二甲基羧酸铵反离子碳链长度对其表面活性和应用性能的影响

通过对不同反离子碳链长度(n=2,4,6,8,10,12)的双癸基二甲基羧酸铵的表面活性及泡沫性能、乳化性能和润湿性能进行测定,探讨反离子碳链长度对季铵盐表面活性剂的表面活性及应用性能的影响。结果表明:随着反离子碳链长度(n=2,4,6,8,10,12)的增加,双癸基二甲基羧酸铵的表面活性逐渐增强,其临界胶束浓度(cmc)逐渐减小,最低表面张力(γcmc)先降低后升高,当反离子碳链长度n=10时,γcmc达到最低,降低水表面张力20 m N/m的效能(pc20)逐渐增大,饱和吸附量(Гtotal)逐渐增大,单个分子占有面积(Am)逐渐减小;泡沫性能和乳化性能均随着反离子碳链长度的增加先增强后减弱;润湿性能随着反离子碳链长度的增加而逐渐增强。     

HTM-12表面活性剂的合成及表面活性

以无水对氨基苯磺酸、1,4-二溴丁烷合成了N,N’-(二对苯磺酸)丁二胺,再与溴代十二烷反应合成N,N’-(十二烷基二对苯磺酸钠)丁二胺(简称HTM-12),合成了带有两个疏水长链的双磺酸盐表面活性剂。该产物水溶液的cmc(7.0×10-4mol/L)是SDBS和DTAB的1/14和1/23,γcmc(26.8 N/m)分别比SDBS(39.0 mN/m)和DTAB(38.9 mN/m)低12.2 mN/m和12.1 mN/m。HTM-12和DTAB复配产生了明显的协同效应。在实验范围的任意配比条件下,HTM-12/DTAB体系的表面活性比SDBS/DTAB高得多。HTM-12∶DTAB=3∶7(摩尔比)时,复配体系的cmc为2.15×10-4mmol/L,γcmc=22.3 mN/m;与SDBS/DTAB的最优化配比(1∶1)相比较,cmc仅为后者的1/3.5,γcmc低10.8 mN/m。     

酯基双子表面活性剂的合成及性能

以环氧氯丙烷、己二酸为原料合成二元酸酯中间体(DBA),再与十二烷基二甲基胺进一步反应合成双酯基阳离子双子表面活性剂(CEGSA)。研究了反应时间、反应温度和催化剂用量对生成物(CEGSA)收率的影响,终产物用傅立叶红外变换仪和元素分析仪进行定性分析;用两相化学滴定法测定活性物含量,产物活性物质质量分数达到93.4%以上,其cmc为0.28 mmol/L,表面张力γcmc=36.5 mN/m。     

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。