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反相微乳液法制备高溶度ZrO2陶瓷墨水(Ⅱ) 总被引:10,自引:0,他引:10
对喷墨打印成型用ZrO2陶瓷墨水的反相微乳液制备法进行了研究.采用已经优化的Triton x-100/正己醇/环己烷/水反相微乳液体系, 以氧氯化锆溶液和氨水溶液分别替代水, 获得了澄清的微乳液, 再将它们均匀混合反应制得了均匀分散、微粒尺寸7~8 nm、稳定存在的ZrO2陶瓷墨水.针对喷射打印墨水的理化性能要求, 考察了所制备的ZrO2陶瓷墨水的理化性能(流变性能、表面张力、电导率、稳定性等), 并对性能改善进行了探讨.所制两个陶瓷墨水当pH<8时, 电导率分别为20 mS/m和35 mS/m, 表面张力分别为21.6 mN/m和34.3 mN/m左右, 粘度为25 mPa*s和32 mPa*s, 且无剪切增稠效应.这些结果说明所制陶瓷墨水的性能指标基本满足非连续式打印机要求.从透光率测试结果表明所制陶瓷墨水属反相微乳液. 相似文献
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采用Triton X-100/正己醇/环己烷/氨水体系配制反相微乳液,在碱性条件下正硅酸乙酯在反相微乳液中发生受控水解,合成了具有无定形结构的球形二氧化硅纳米粒子。通过红外光谱(FT-IR)、X衍射(XRD)、透射电镜(TEM)分别对样品的结构及形貌尺寸进行了表征和分析。结果表明:改变表面活性剂加入量可以得到不同粒径(50~110nm)、不同粒度分布及不同分散程度的球形二氧化硅纳米粒子。随着表面活性剂在微乳液中体积分数的增大,二氧化硅纳米粒子的粒径先减小后增大,团聚程度也呈现先减小后增大的趋势。当表面活性剂在微乳液体系中的体积分数为20%时,所合成的二氧化硅纳米粒子粒径最小(50nm),粒度均匀且呈现出良好的分散性。 相似文献
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通过测定微乳液的电导率值,确定配制W/O型Triton X-100/正构醇/石油醚/水微乳液的最大增溶水量;根据微乳液含水量与电导率关系曲线及体系的拟三元相图,讨论了正构醇种类、正构醇含量、乳化剂与油相质量比对W/O型微乳液的结构、电导率、增溶水量的影响。结果表明:乳化剂与油相质量比大于1时,正戊醇、正己醇和正庚醇为助剂配制的Triton X-100/正构醇/石油醚/水体系微乳液有较大的增溶水量,而乳化剂与油相质量比大于1.5时,以正丁醇为助剂配制的Triton X-100/正构醇/石油醚/水体系微乳液才有较大的增溶水量;正构醇的链长及加入量影响微液滴界面膜的强度,从而影响微乳液的增溶水量、电导率及微乳液形成区域的大小;对于Triton X-100/正构醇/石油醚/水体系,正戊醇是形成W/O型微乳液的较好助剂,当正戊醇与Triton X-100的质量比为0.5时,W/O型微乳液的形成区域最大。 相似文献
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两种反相微乳液体系合成纳米羟基磷灰石的比较 总被引:2,自引:0,他引:2
制备了两种稳定的CTAB/正丁醇/正己烷/水体系和TritonX-100/正己醇/环己烷/水反相微乳液体系,研究了微乳液组份的浓度和比例对微乳液性质的影响,比较了两种反相微乳液体系的三元相图,用“微反应器”合成了纳米羟基磷灰石(HAP)粉体,比较了HAP颗粒在X-射线衍射、TEM、SEM表征中的异同。两种体系都表明反向微乳液法可以有效地控制和改变HAP的分散性和粒度大小。 相似文献
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《现代化工》2021,(2)
在Triton X-100/正己醇/环己烷/水反相微乳液体系中,分别采用一步法和两步法制备具有核/壳结构的磁性Fe_3O_4@SiO_2复合纳米粒子。考察了搅拌方式和超声条件对一步法产物结构、形貌的影响,并与两步法进行了对比研究。通过XRD、FT-IR、DLS、TEM和VSM对复合颗粒进行了表征。结果表明,反相微乳液体系下,一步法获得的纳米粒子团聚严重、无明显的核/壳结构,且搅拌方式和超声因素对产物微观结构影响较小;而采用两步法可以获得形貌规整的核/壳结构Fe_3O_4@SiO_2复合纳米粒子,其室温下的磁滞回线呈超顺磁性,饱和磁化强度为37.8 emu/g。 相似文献
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以Triton X-100/正己醇/环己烷/水制成W/O微乳反胶团体系,通过测定体系的电导率和观察液晶相的出现确定相点绘制了各体系的拟三元相图,研究了温度、盐浓度和油相组分对W/O微乳液体系稳定性的影响.实验发现助表面活性剂与表面活性剂的配比对微乳液的稳定性有显著影响.随着温度的升高,W/O微乳液稳定区域减小,可通过升高温度对微乳液进行破乳;与以纯环己烷为油相的体系相比,油相中含有少量正己烷的体系具有更优异的性质.所得结果为利用该W/O微乳液体系制备纳米颗粒提供了基础数据. 相似文献
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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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J. R. Aldrich S. P. Carroll W. R. Lusby M. J. Thompson J. P. Kochansky R. M. Waters 《Journal of chemical ecology》1990,16(1):199-210
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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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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
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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
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
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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. 相似文献
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2008~2009年世界塑料工业进展 总被引:4,自引:1,他引:3
中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2010,38(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
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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 总被引:15,自引:0,他引:15
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