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1.
本工作测定了含少量离子表面活性剂(包括阳离子型的溴代十二烷基三甲铵(DTAB)、溴代十六烷基三甲铵(CTAB)和阴离子型的十二烷基硫酸钠(SDS)、十六烷基硫酸钠(SCS))的聚丙二醇(PPG)水溶液的浊点,结果表明:离子表面活性剂的加入总使得PPG溶液的浊点升高:对同系到的离子表面活性剂而言,碳氢链越长,这种作用越强:阴离子表面活性剂的作用要比碳氢链长度相同的阳离于表面活性剂的强烈。在PPG溶液中加入少量无机盐(如NaCl和Na_2SO_4)对浊点无影响,但当溶液中含有离子表面活性剂时,少量盐的加入则会使浊点降低。这种降低作用与盐的浓度和离子的种类有关,对于0.01%PPG+SCS和0.1%PPG+SCS体系,盐的阳离子价数起决定作用,作用能力为:1/3 LaCl_3>1/2 CaCl_2>NaCl。对于0.1%>PPG+CTAB体系,盐的阴离子价数起决定作用,作用能力为:1/3 K_3Fe(CN)_6>1/2 Na_2SO_4>NaBr然而,对于0.01%PPG+CTAB体系,观察到了一个奇异的现象,即电解质的加入使浊点上升而不是下降,对此,文中提出了一种可能的解释,认为电解质的加入能促进表面活性剂离子在PPG链上的吸附,从而使浊点升高。  相似文献   

2.
研究了含三嗪环阴离子Gemini表面活性剂增溶、流变、溶致液晶、囊泡等性能。结果表明:增溶量随Gemini表面活性水基和联接基长度)对其水溶液的黏度有相同的影响;C6-2-C6、C8-2-C8、C8-3-C8、C8-4-C8、C8-6-C8、C12-2-C12在质量分数剂疏水链长度的增长而增大,C8-n-C8(n=23,4,6,)的增溶量随联接基长度增加而增加,C12-2-C12与SDS的复配体系比SDS的增溶量大,C12-2-C12与CTAB的复配体系比这2种表面活性剂单独使用时的增溶量小;Gemini表面活性剂溶液分子结构(疏分别为42.3%,37.8%,33.5%,30.4%,27.6%2,0.3%时均产生层状的溶致液晶;0.01 mol/L的单一Gemini表面活性剂水溶液均不能形成囊泡,而当n(C12-2-C12)∶n(CATB)为8∶2或9∶1时,复配体系的水溶液形成了大量的囊泡结构。  相似文献   

3.
研究了浊点萃取(CPE)-紫外可见光谱法(UV/Vis)测定微量钴的新方法,利用表面活性剂聚乙二醇辛基苯基醚(TritonX-100)和配合剂2[(5-溴-2-吡啶)-偶氮]-5-(二乙氨基)苯酚(5Br-PADAP)对试样中的钴(Ⅱ)进行浊点萃取。探讨了影响浊点萃取及测定灵敏度的因素。在最佳条件下,钴的富集倍率为5,检出限为1.18ng/mL(n=11),RSD为2.8%(n=5,c(Co2+)=0.20μg/mL),钴含量在(0.01~0.5)μg/mL范围内服从比尔定律。本法对实际样品中的钴进行富集和测定,结果令人满意。  相似文献   

4.
姚志钢  李干佐  胡艾希 《精细化工》2003,20(11):655-659
采用1,4-丁二醇、马来酸酐、十二烷基聚氧乙烯醚(AEO2)为主要原料和环境友好的工艺路线,合成了一种易降解的双子(Gemini)表面活性剂--二元醇双琥珀酸双酯磺酸钠(GMI-01).对各步合成条件采用正交实验或均匀设计进行优化,得出各步反应的最优工艺条件如下酯化反应Ⅰ,配比为n(马来酸酐)∶n(1,4-丁二醇)=2.15∶1.00,反应时间1 h,催化剂w(乙酸钠)=1.0%,以丙酮作溶剂,回流操作.酯化反应Ⅱ,配比为n(1,4-丁二醇双马来酸单酯)∶ n(AEO2)=1.00∶2.15,反应温度150 ℃,反应时间14 h,催化剂w(PW12/C)=1.5%.磺化反应, 配比为n(1,4-丁二醇双马来酸AEO2双酯)∶ n(NaHSO3)=1.00∶3.00,反应时间4 h,反应温度80 ℃,相转移催化剂w(CTAB)=1.5%.对每步合成产物均用 IR和1HNMR进行了表征,终产物GMI-01的平衡表面张力γCMC=38.4 mN/m,CMC为0.049 mmol/L.  相似文献   

5.
以α-溴代十四酸乙酯和4-癸基苯酚为原料,经Williamson醚化、磺化及皂化反应制备了一种不对称阴离子Gemini表面活性剂α-(4-癸基-2-磺基)-苯氧基十四酸钠,简写为C12CO2Na-p-C10SO3Na,考察了醚化反应条件,并用FTIR和1HNMR表征了中间体及目标产物结构。结果表明,醚化反应的最佳条件为:以N,N-二甲基甲酰胺(DMF)和甲苯作溶剂,无水K2CO3作缚酸剂,物料比n(α-溴代十四酸乙酯)∶n(4-癸基苯酚)=1.05∶1,回流反应3 h,醚化产物收率为77.2%(以4-癸基苯酚计)。采用吊片法测定了目标产物的表面活性,其表面张力最低可降至26 mN/m左右,临界胶束浓度(CMC)为3.28×10-6mol/L,比相应常规单链表面活性剂十四烷酸钠和间癸基苯磺酸钠的CMC低3个数量级,体现出Gemini表面活性剂优异的表面活性。  相似文献   

6.
离子选择电极法分析非离子/阴离子表面活性剂体系   总被引:2,自引:1,他引:1  
利用自制表面活性剂离子选择电极,采用电位滴定法测定了非离子表面活性剂脂肪醇聚氧乙烯醚(AEO9)与阴离子表面活性剂十二烷基硫酸钠(SDS)混合溶液中的SDS浓度。当AEO9与SDS的摩尔比约小于2∶1时,可用此种方法定量测定混合体系中的SDS的浓度,与滴定单一SDS溶液的结果对照,相对误差在1%以内。  相似文献   

7.
焙烧钾长石制硫酸钾的实验研究   总被引:3,自引:0,他引:3  
系统研究了钾长石-硫酸钙-碳酸钙体系提钾反应的物料配比、焙烧温度、反应时间和Na2SO4添加量对热分解的影响,最后得出物料摩尔配比为n(KAS6)∶n(CaSO4)∶n(CaCO3)=1∶1∶14。在1 423 K温度下反应2 h,钾长石中钾溶出率为92.02%。当Na2SO4添加量为2.94%(质量百分比),反应温度可降为1 273 K,此时钾溶出率可达92%~94%。对焙烧产物进行了XRD分析,得出其主要物相为K2SO4、C3A和C2S,并确定其热分解化学方程式,进行热力学计算。  相似文献   

8.
王旗威  耿兵  张炉青  张德宾  张书香 《精细化工》2011,28(4):347-349,374
研究了含氟烷基磷酸单酯类表面活性剂[分子式为H(CF2)6CH2OPO(ONa)2,记为DFH-PS]与无机盐和普通碳氢表面活性剂的复配性能,研究结果表明,DFH-PS水溶液最低表面张力为23.73 mN/m;当NaCl浓度为0.2 mol/L时,可使DFH-PS水溶液最低表面张力下降到21.62 mN/m;阴离子碳氢表面活性剂十二烷基硫酸钠(SDS)对该含氟表面活性剂影响显著,当n(DFH-PS)∶n(SDS)=5∶1时,可使水溶液表面张力在很低浓度时降至22.22 mN/m;与非离子表面活性剂辛基酚聚氧乙烯(10)醚(OP-10)混合,当n(DFH-PS)∶n(OP-10)=8∶1时,可使水溶液表面张力降至27.0 mN/m。  相似文献   

9.
姚志钢李干佐  胡艾希 《精细化工》2003,20(11):655-659,704
采用1,4 丁二醇、马来酸酐、十二烷基聚氧乙烯醚(AEO2)为主要原料和环境友好的工艺路线,合成了一种易降解的双子(Gemini)表面活性剂———二元醇双琥珀酸双酯磺酸钠(GMI-01)。对各步合成条件采用正交实验或均匀设计进行优化,得出各步反应的最优工艺条件如下:酯化反应Ⅰ,配比为n(马来酸酐)∶n(1,4 丁二醇)=2 15∶1 00,反应时间1h,催化剂w(乙酸钠)=1 0%,以丙酮作溶剂,回流操作。酯化反应Ⅱ,配比为n(1,4 丁二醇双马来酸单酯)∶n(AEO2)=1 00∶2 15,反应温度150℃,反应时间14h,催化剂w(PW12/C)=1 5%。磺化反应,配比为n(1,4 丁二醇双马来酸AEO2双酯)∶n(NaHSO3)=1 00∶3 00,反应时间4h,反应温度80℃,相转移催化剂w(CTAB)=1 5%。对每步合成产物均用IR和1HNMR进行了表征,终产物GMI-01的平衡表面张力γCMC=38 4mN/m,CMC为0 049mmol/L。  相似文献   

10.
研究了脱硫灰中的微量组分Na2SO4、Fe2O3、CaCl2及B2O3对钾长石-硫酸钙-碳酸钙体系热分解的影响.在物料配比为n(KAS6)∶n(CaSO4)∶n(CaCO3)=1∶1∶14的条件下,加入不同量的Na2SO4、Fe2O3、CaCl2及B2O3分别在1223 K、1323 K和1423 K下进行焙烧.研究结...  相似文献   

11.
12.
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   

13.
14.
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   

15.
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.
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   

18.
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。  相似文献   

19.
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   

20.
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   

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