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1.
从工艺技术角度分析了影响陶瓷耐热锅热稳定性的因素;探讨了材料组成、原料细度、坯釉结合性、烧成制度对产品热稳定性的影响。并结合生产实际提出了改善产品热稳定性的方法和措施。  相似文献   

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唐志阳 《陶瓷》2012,(5):12-13
简述了锂质耐热陶瓷炊具的特点,从坯料的组成、原料细度、坯釉的适应性、烧成制度和炊具造型几个方面探讨了影响锂质耐热陶瓷炊具热稳定性的因素。  相似文献   

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唐志阳 《陶瓷》2012,(9):12-13
简述了锂质耐热陶瓷炊具的特点,从坯料的组成、原料细度、坯釉的适应性、烧成制度和炊具造型几个方面探讨了影响锂质耐热陶瓷炊具热稳定性的因素。  相似文献   

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一、序言在坯釉适应性研究的1—6中论述了陶瓷器抗开裂性的比较基本的几个因素:釉应力测定方法;抗开裂性与瓷坯的热膨胀系数及其与石英、方石英含量的关系;釉应力的温度变化与瓷坯及釉的热膨胀曲线的关系;瓷坯的釉层变质、陶瓷器的高压釜处理引起的釉应力变化;以及反复釉烧产生的釉和瓷坯  相似文献   

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本探讨了微波炉用高级日用陶瓷的坯釉配方、坯体成型对石膏模工艺性能的要求及装饰工艺。  相似文献   

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用透锂长石取代锂辉石生产出热膨胀系数1.86×10^-7、抗热震性能700℃至20℃水冷却不裂的陶瓷耐热炊具,并分析了透锂长石在坯釉配方上的作用和对生产工艺的影响。  相似文献   

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日用精陶釉面发生开裂,在技术上和使用上,都是一个严重的缺陷。产品釉面开裂(简称釉裂,下同)是由以下三个主要因素造成的:一、坯釉膨胀系数的不相适应;当坯体的膨胀系数值(可用α坯表示,下同)比釉的膨胀系数值(可用α釉表示,下同)低时,釉面受张应力而发生开裂。当α坯>α釉时,釉面受压应力,坯釉结合倾向剥釉;二、坯釉中间层形成的状况,当经过合理的素烧和釉烧后,坯和釉相接触的界面形成了中间层,它能提高产品的热稳定性,增加抵抗产品后期釉裂的能力;三、素坯湿膨胀率  相似文献   

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本文介绍了一种用钾钠长石、玻璃粉、石英、方解石等原料,用单因素和正交试验进行实验研究。通过调整长石的加入量、烧成温度、釉层厚度、球磨时间、坯体的热膨胀系数等因素,获得了釉面效果较好的冰裂纹釉。实验结果表明,较好釉面效果的配方组成为(wt%)为:钾长石35,钠长石40,方解石3,高岭土4,石英6,碳酸钡2,玻璃粉9,氧化锌1。当坯釉热膨胀系数之差≥3.54×10-6/℃时,冰裂纹效果最好。  相似文献   

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俞秋玉 《陶瓷》1999,(5):28-29
成功研制了堇青石质耐热炻器用低膨胀无光釉,釉料和坯体结合良好.因坯釉中滑石成分高,坯釉剧烈反应而使中间层过度发育增厚至釉面,釉面出现“吸干”现象.文中对抑制这种中间层的增厚从而改善釉面质量进行了肤浅研究和探讨.  相似文献   

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徐庆芝  杨剑 《陶瓷》2003,(3):34-34,37
1 耐磨无光釉的特点适宜于一次烧成工艺 ;烧成温度范围宽 ,原料丰富 ;可用全生料作原料 ,也可适当加入少量熔块 ;烧成缺陷容易控制 ;经济效益显著。2 配方研制2 .1 坯体配方的选择耐磨釉面砖属于高档釉面砖 ,对坯体的要求较高 ,要求坯体有较高的白度 ,吸水率≤ 0 .5 % ,且适应釉的烧成温度。2 .2 釉料配方的研制1)耐磨釉试验所用原料的化学成分如表 1所示。表 1 釉用原料的化学成分 (质量 % )SiO2 Al2 O3Fe2 O3TiO2 CaOMgOK2 ONa2 OZnO烧失长 石 67.0 3 1 7.83 0 .0 90 .2 7 0 .1 4 2 .1 82 .51 0 .1 8氧化铝 98.72石灰石 3 .…  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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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   

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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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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   

17.
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   

18.
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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