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1.
以新疆夏子街钙基膨润土为原料,进行了原矿湿法提纯、钠化改性及钠基土有机化改性及其应用研究.结果表明,湿法提纯前钙基膨润土的蒙脱石含量为91.79%,是一种高品位钙基膨润土,提纯后蒙脱石含量达到95.97%.钠化正交实验结果表明,NaF效果优于传统的钠化剂Na2CO3.在优化条件下钠化改性膨润土的阳离子交换容量(CEC)可达97.5 mmol/100g土,比原矿提高17.25 mmol/100g土.以钠化改性膨润土为原料制得的有机膨润土的粘度达到5.4 Pa*s.FTIR表明有机插层剂已进入膨润土的层间.XRD特征峰位移表明有机膨润土的层间距达到2.143 nm,比钙基膨润土层间距增加0.754 nm.SEM得到的结论与FTIR、XRD表征结果相吻合.将有机膨润土应用于涂料中,其各项检测指标均满足要求.有机膨润土对于金属离子废水的吸附效果优于钙基膨润土.由此可知新疆夏子街钙基膨润土的高附加值开发是可行的.  相似文献   

2.
以新疆乌兰陵格膨润土为原料,进行了原矿湿法提纯、钙基膨润土钠化改型及钠基膨润土有机化改性用于钻井油基泥浆的研究.结果表明,湿法提纯前钠基膨润土的蒙脱石含量为57.55%;提纯后蒙脱石含量为60.91%.而钙基膨润土蒙脱石含量为56.53%,提纯后蒙脱石含量为59.48%.Na2CO3作为改型剂使钙基土的CEC(阳离子交换容量)提高了26.7%,钠化改型后所制得的有机土的粘度达到0.840Pa·s.季铵盐用量在(8.5~9.0)×10-4mol/g时,D1631有机土的粘度出现了明显的突变点.FTIR表明有机插层剂已进入膨润土的层间.XRD特征峰位移表明膨润土的层间距有明显增加.SEM观察也表明膨润土的层间距增大,层间厚度约为72nm.将有机膨润土应用于钻井油基泥浆中,各项指标均已达到要求,研究表明新疆乌兰陵格膨润土的高附加值开发是可行的.  相似文献   

3.
剥离型葡萄糖酸蒙脱石的制备及其表征   总被引:2,自引:0,他引:2  
利用葡萄糖酸改性碱性钙基膨润土制备了一种与水溶性高分子材料亲合性较强的剥离型葡萄糖酸蒙脱石.通过单因素实验,分析了葡萄糖酸用量、反应温度、分散剂浓度等因素对葡萄糖酸蒙脱石剥离的影响,认为蒙脱石剥离可能是由于层间发生激烈的中和反应造成的.电子显微镜扫描表明这种剥离型蒙脱石为片状结构,纳米片的厚度为75~100 nm; DSC测定表明该葡萄糖酸蒙脱石的失水温度与葡萄糖酸钙相同,葡萄糖酸基团分布在纳米片的表面上;IR 扫描表明葡萄糖酸与蒙脱石的结合方式为化学键;XRD表征说明该葡萄糖酸蒙脱石仍为层状结构,为多层蒙脱石晶片组成.将该葡萄糖酸蒙脱石添加到木薯淀粉糊中,能使淀粉糊的黏性增加一倍.  相似文献   

4.
陈洁  李远才  熊建民  夏春 《粘接》2007,28(5):14-16
在微波加热条件下制备酚醛树脂/有机改性蒙脱石纳米复合材料,研究了蒙脱石不同加入方法、不同加入量和搅拌时间对有机改性蒙脱石分散效果的影响,并用X射线小角衍射观测其微观结构。结果表明,苯酚和甲醛可以进入蒙脱石片层间进行缩聚反应,使蒙脱石片层间距扩大甚至剥离。  相似文献   

5.
以钙基膨润土为原料,经提纯钠化改性,用十六烷基三甲基氯化铵对其进行有机改性。研究了改性剂用量、反应温度和反应时间对改性膨润土有机化程度的影响,得到了最佳实验条件:改性剂用量为35%(以钠基膨润土质量计)、反应温度为70 ℃、反应时间为2 h。利用红外光谱仪和X射线衍射仪对最优样品进行测试分析,结果表明:季铵盐插层进入了膨润土的晶层间,层间距明显增大,改性效果良好。  相似文献   

6.
以钙基蒙脱石为原料,氟化钠为钠化剂,十六烷基三甲基溴化铵为有机改性剂采用离子交换法制备了有机蒙脱石(CTA-MMT);以硝酸镁、硝酸铝、氢氧化钠和十二烷基磺酸钠为原料,采用水热法制备了有机型镁铝层状双氢氧化物(Mg Al-SDS-LDH);以氯仿为剥离介质,采用超声法剥离CTA-MMT和MgAl-SDS-LDH,分别获得了两种剥离型矿物溶胶,将其混合自组装制备了蒙脱石/层状双氢氧化物(MMT/LDH)组装材料。用XRD和AFM表征了CTA-MMT和MgAl-SDS-LDH及其剥离产物,并分析了组装材料的热稳定性。结果表明,CTA-MMT和MgAl-SDS-LDH在氯仿介质中剥离仅需20 min,剥离型CTA-MMT和MgAl-SDS-LDH片层平均厚度分别约为9和8 nm。MMT/LDH由剥离型CTA-MMT和MgAl-SDS-LDH片层有序组装而成,组装材料结构与MgAl-SDS-LDH和CTA-MMT的含量有关,其结构单元层间距2.59 nm(CTA-MMT含量较低时)随着组装材料中CTA-MMT含量的升高而转变为1.82 nm。MMT/LDH组装材料具有较单一的CTA-MMT或MgAl-SDS-LDH更高的热稳定性。  相似文献   

7.
采用十六烷基三甲基溴化铵为插层剂,通过先机械搅拌后超声振荡的复合工艺对钠基蒙脱土进行了有机改性,制备了超分散蒙脱土并对其进行了表征.FTIR表明有机插层剂进入蒙脱土层间;XRD结果表明超分散蒙脱土层间距由改性前的1.01 nm增加到3.13 nm;SEM和TEM表明蒙脱土已被剥离成单个片层.粒径分析表明超分散蒙脱土有很好的亲油性和分散性;沉降对比实验说明超分散蒙脱土分散性好,可长时间悬浮在熔融己内酰胺中.  相似文献   

8.
通过对钙基膨润土钠化和有机改性,制备出了可抗240℃的白油基钻井液用有机土。测试表征及评价结果表明,改性后季铵盐类有机覆盖剂进入蒙脱石层间,在蒙脱石表面发生化学键连,晶层间距增大到18.78,有机土层片变得疏松;与国内外有机土相比,该有机土在白油中胶体率高,抗温性强,能起到很好的增粘提切和较好的流变性能,具有较好的推广前景。  相似文献   

9.
马来酸酐改性蛭石的制备及表征   总被引:1,自引:0,他引:1  
以有机小分子马来酸酐作为改性剂,利用球磨法在不同溶剂中对蛭石进行有机改性.对有机改性的蛭石进行了X射线粉晶衍射、Fourier变换红外光谱仪和热重分析表征.结果表明:在水溶液条件下,球磨能够使蛭石片层被马来酸酐分子剥离,蛭石的(001)面特征衍射峰消失.在有机溶剂中球磨,蛭石不能够被马来酸酐剥离.讨论了马来酸酐改性蛭石的机理.研究了球磨时间对马来酸酐改性蛭石的影响.  相似文献   

10.
钙钠基蒙脱石铝柱撑的制备和表征   总被引:3,自引:1,他引:2  
以山西大同的钙钠基蒙脱石为原料,制备了铝柱撑蒙脱石.通过XRD,FT-IR,N2吸附-脱附等测试手段,分析了产物的层间距、比表面、孔特征和结构变化.结果表明:钙钠基蒙脱石铝柱撑能获得比较好的柱撑效果,层间距为1.94nm,BET比表面为273.87m2/g,微孔容积为0.1174cm3/g,微孔孔径的最可几分布为0.738nm,中孔孔径的最可几分布为3.766nm.  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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