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1.
通过考察酯基Gem in i型季铵盐表面活性剂Ⅱ-10-n(n=3,4,6)与十二烷基聚氧乙烯(9)醚(AEO9)的复配体系的表面活性发现,复配体系的临界胶团总浓度CMCT值介于二元复配体系中各组分的临界胶团浓度CMC01和CMC02之间。当溶液中含有少量AEO9时(在溶液体相中的摩尔分数α2=0.1),混合胶团中AEO9的摩尔分数均已超过0.35;随着溶液中AEO9含量的增大,混合胶团中逐渐以AEO9为主成分。复配体系的混合胶团聚集数介于二元复配体系中各组分的胶团聚集数之间,随着溶液中酯基Gem in i型季铵盐表面活性剂含量的增加,混合胶团聚集数逐渐减少。  相似文献   

2.
各类添加剂都能对非离子表面活性剂的浊点产生影响.今研究了离子型表面活性剂、增溶物和电解质类添加剂在不同浓度下对非离子表面活性剂AEO9浊点的影响.其中离子型表面活性剂和增溶物类添加剂可在极低的浓度上改变AEO9的浊点,且随着添加剂加入浓度的增加,AEO9的浊点也逐渐增加,当添加剂浓度达到离子型表面活性剂或增溶物的临界胶束浓度时,AEO9的浊点将出现急剧上升.而电解质类添加剂对AEO9浊点的影响表现出具有临界浓度现象,只有当添加剂的浓度达到相应的临界浓度之后,具有盐析效应的电解质将使AEO9浊点线性下降,而具有盐溶效应的电解质则使AEO9浊点线性升高,且不同电解质相应的临界浓度随着其阴离子的感胶离子数的增大而线性增加,同时其对AEO9浊点的改变程度则随着阴离子的感胶离子数的增大而线性下降.  相似文献   

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基于表面活性剂固-液界面吸附理论,在无搅拌条件下研究了十二烷基硫酸钠(SDS)、脂肪醇聚乙烯醚硫酸钠(AES)、脂肪醇聚乙烯醚(AEO)3种表面活性剂在不锈钢反应釜中对甲烷水合物生成的促进效果。结果表明:水合物的生成形态与表面活性剂吸附金属表面形态有良好的对应关系;SDS与AES在金属表面的吸附作用可使水合物成核速率提高,成核位置增多。由于AEO不能在金属壁面发生吸附,导致对水合物生成促进效果降低,在浓度为300 mg·L~(-1)的SDS、AES和AEO溶液中,水合物储气密度及平均储气速率分别为131.4、128.3、12.3(体积比)和5.8、7.6、0.07 mmol·min~(-1);逐步提高SDS溶液浓度(80~1200 mg·L~(-1))和AES溶液浓度(60~1350 mg·L~(-1)),水合物储气密度首先增大然后减小,储气速率线性增大。因此,合理选择表面活性剂种类及浓度,可显著促进水合物生成。  相似文献   

4.
本文研究烷基酚聚氧乙烯醚型非离子表面活性剂TritonX-100水溶液的浊谱性质。得到了与脂肪醇聚氧乙烯醚非离子表面活性剂AEO9相类似的典型浊谱曲线以及浊度-浓度线性关系区间,发现TritonX-100水溶液同样具有反常浊谱行为。首次研究了表面活性剂浓度对起始浊点、最大浊度值的影响,发现上述关系曲线在浓度为500×10~(-6)时存在一致的拐点,初步解释了这种现象。同时研究了升温速率对其浊谱特性的影响。  相似文献   

5.
研究了非离子生物表面活性剂茶皂素(TS)和阴离子表面活性剂十二烷基硫酸钠(SDS)复配体系的表面活性及无机盐的影响、浮选去除废水中铜离子的处理效果。结果表明,当TS与SDS的混合比例为0.2∶1~0.3∶1时,复配体系的表面张力和临界胶束浓度均降至最低,起泡性和稳泡性均比较稳定;无机盐主要对溶液中的SDS表面活性产生影响,茶皂素性质比较稳定,基本不受影响。采用TS∶SDS=0.25∶1的复配体系进行浮选,溶液中铜离子的去除效率可以达到92%。  相似文献   

6.
以异构十醇为起始剂,经烷氧基化反应制得一种新型洗衣凝珠用非离子表面活性剂DPE8,并采用红外和氢核磁共振谱证实了其结构。研究了DPE8的相行为以及泡沫、乳化、渗透等性能,并与传统非离子表面活性剂月桂基聚氧乙烯醚-9(AEO9)对比。结果表明,DPE8具有远低于AEO9的凝点、更窄的凝胶相区间以及更快的溶解速度;与此同时,DPE8表现出低起泡性和低稳泡性;并且DPE8的乳化力是AEO9的1.4倍,渗透力是AEO9的10倍。因此,DPE8具有取代AEO9应用于洗衣凝珠产品的潜力。  相似文献   

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表面活性剂吸附对促进甲烷水合物生成效果的影响   总被引:1,自引:1,他引:0       下载免费PDF全文
基于表面活性剂固-液界面吸附理论,在无搅拌条件下研究了十二烷基硫酸钠(SDS(、脂肪醇聚乙烯醚硫酸钠(AES(、脂肪醇聚乙烯醚(AEO(3种表面活性剂在不锈钢反应釜中对甲烷水合物生成的促进效果。结果表明:水合物的生成形态与表面活性剂吸附金属表面形态有良好的对应关系;SDS与AES在金属表面的吸附作用可使水合物成核速率提高,成核位置增多。由于AEO不能在金属壁面发生吸附,导致对水合物生成促进效果降低,在浓度为300 mg·L-1的SDS、AES和AEO溶液中,水合物储气密度及平均储气速率分别为131.4、128.3、12.3(体积比(和5.8、7.6、0.07 mmol·min-1;逐步提高SDS溶液浓度(80~1200 mg·L-1(和AES溶液浓度(60~1350 mg·L-1(,水合物储气密度首先增大然后减小,储气速率线性增大。因此,合理选择表面活性剂种类及浓度,可显著促进水合物生成。  相似文献   

8.
采用十二烷基聚氧乙烯醚(AEO9)双水相胶束体系进行苯酚的萃取,考察Na2SO4和NaCl对质量浓度为50 g/L AEO9水溶液体系浊点的影响。结果表明,Na2SO4对浊点下降的影响比NaCl大,当盐的浓度均为0.6 mol/L,添加Na2SO4时浊点为28.5℃,而添加NaCl时为36.5℃。研究了无机盐(Na2SO4和NaCl)、普通离子型表面活性剂(十六烷基三甲基溴化铵CTAB和十二烷基硫酸钠SDS)和gemini型酯基季铵盐阳离子表面活性剂(Ⅱ-12-6)对苯酚萃取率E的影响。结果表明,盐的加入会使E下降,但Na2SO4对E的影响比NaCl要小;添加SDS使E下降,并随着n(SDS)∶n(AEO9)的增加而下降;而添加CTAB或Ⅱ-12-6均使E明显提高,且随着n(CTAB)∶n(AEO9)、n(Ⅱ-12-6)∶n(AEO9)的增加而进一步提高;但在同等条件下添加Ⅱ-12-6的E高于添加CTAB。  相似文献   

9.
肖勇 《云南化工》2009,36(3):28-30
研究了阴离子表面活性剂十二烷基硫酸钠(SDS)对非离子表面活性剂CM101浊点的影响。结果表明:当SDS加入量为2%时,CM101的浊点提高到59.6℃,达到农药制剂热稳定性的要求。同时,该混合体系满足非理想二元表面活性剂复配增效的条件,表面张力和临界胶束浓度都有明显降低。  相似文献   

10.
通过对稀溶液表面性能和浓溶液相行为的研究,探讨了乙醇对AEO9水溶液性能的影响。结果表明,随着乙醇用量的增加,AEO9在乙醇/水混合溶剂中的临界胶束浓度(cmc)增大,但cmc时的表面张力(γcmc)基本不变。三元相图中,在AEO9/乙醇一侧只有胶束溶液,没有液晶区出现;靠近AEO9/水一侧,随着AEO9含量的增加,由胶束溶液逐渐向六角相液晶和层状相液晶过渡。  相似文献   

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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.  相似文献   

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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.  相似文献   

15.
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.  相似文献   

16.
2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
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。  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

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