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为得到导电性良好的棉织物,采用硫酸镍超声活化法制备化学镀镍导电棉织物。用EDS和SEM对镀层的化学成分以及表面形貌进行表征,并对镀镍后棉织物的表面方阻、增重率、耐摩擦性能和拉伸断裂强度进行测试。探讨了温度、pH、NiSO4·6H2O 浓度、NaH2PO2·H2O浓度对棉织物增重率、表面方阻的影响。结果表明:在m(NiSO4·6H2O):m(NaH2PO2·H2O):m(H2O)=1.5:2:30,温度60 ℃,频率为40 KHz,功率为320W的条件下超声活化30 min后,以NiSO4·6H2O浓度25 g/L,NaH2PO2·H2O浓度20~25 g/L,Na3C6H5O7·2H2O浓度5 g/L,C2H3NaO2浓度5 g/L,温度90 ℃,pH 5~6,反应时间1 h时。所制备的镀镍导电棉织物表面方阻最小,最好可达71.67 mΩ/□且具有良好的耐摩擦性能。良好的导电性以及耐摩擦性能使其能更好的应用在智能纺织品上。 相似文献
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借助X射线衍射(XRD)和扫描电镜(SEM)表征,以CuSO4·5H2O和NaC2H3O2·3H2O为主要原料,D 山梨醇为还原剂,水热还原制备了Cu2O微米棒。具体条件是:n(CuSO4·5H2O)∶n(NaC2H3O2·3H2O) =1∶4,D 山梨醇的加入量与CuSO4·5H2O等摩尔,水热180℃下反应12h。微米棒的直径小于1μm,长度在10μm以上,棒表面有晶体生长印迹。其机理是:C2H3O-2 水解生成OH-,OH-与Cu2+生成Cu(OH)2,Cu(OH)2 再被D 山梨醇还原生成Cu2O。 相似文献
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化学还原法制备导电涂料用片状超细铜粉的研究 总被引:12,自引:1,他引:12
以CuSO4·5H2 O为原料 ,抗坏血酸为还原剂 ,NH3 ·H2 O为络合剂 ,将络合剂在反应温度加到CuSO4·5H2 O溶液中 ,再加入还原剂 ,制备了粒径分布为 1~ 10 μm的片状铜粉。探索与分析NH3 ·H2 O的用量、反应温度和CuSO4浓度对铜粉形貌及产率的影响。结果表明 :络合剂的使用是制备片状超细铜粉的关键 ,其与Cu2 + 形成络合物 ,减少溶液中游离Cu2 + 的浓度 ,控制铜的生成速度 ,并影响铜的成核和生长 ,最终形成片状铜粉。 相似文献
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用Al2(SO4)3·18H2O、MgSO4·7H2O及Na2CO3作原料,在适量表面活性剂聚乙二醇辛基苯基醚(OP)的存在下,在室温下充分混合研磨,得到反应混合物,洗去其中的可溶性无机盐后烘干,即可得到纳米碱式碳酸铝镁。基于均匀设计、逐步回归分析及最优计算,对碱式碳酸铝镁的固相合成条件进行优化。结果表明,优化的工艺条件为:Al2(SO4)3·18H2O取10mmol时,n[Al2(SO4)3·18H2O]∶n(MgSO4·7H2O)∶n(Na2CO3)=1∶4.5∶9,表面活性剂OP用量40μL,研磨时间40min。在此条件下合成的碱式碳酸铝镁粉末一次粒子的平均粒径约80nm,其形貌为球形,收率为95.2%。 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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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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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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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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