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51.
本文分析了离心复合铸造轧辊生产过程中离心机停机温度和时间对轧辊质量的影响 ,提出了用先进的红外测温技术来预报停机温度和时间 ,以实现微机监控适时停机 ,保证轧辊内外层熔合良好 ;同时指出了红外测温技术在离心复合铸造轧辊生产上的应用前景 相似文献
52.
The synthesis and characterization of Ti–xMg (x=4, 9, 12, 15, 21, 24 at%) alloys using mechanical alloying was investigated. A nanometer-sized Ti–24Mg alloy was produced. During mechanical alloying, the height of the XRD peaks of the Mg in the Ti–9Mg alloy decreased, and then disappeared, whereas the Ti XRD peaks broadened, and the grain size decreased with increasing milling time. The Mg firstly dissolved in the grain boundaries of the Ti, and then diffused into the Ti grain interiors. The grain boundaries played an important role in enhancing the solid solubility of Mg in Ti. With increasing Mg content the volume fraction of grain boundaries increased, and a decrease in grain size occurred after mechanical alloying for 48 h. 相似文献
53.
54.
本文简要阐述了北化院BCS01和上海院SLC-S两种国产气相聚乙烯浆液催化剂的性能、催化剂结构,在Unipol聚乙烯工业装置上应用结果,以及和进口同类催化剂UCAT-J的性能比较。 相似文献
55.
系统研究了苏州高岭土碳热还原氮化合成SiAlON过程在不同温度下的相变。对试样的XRD、SEM以及EDXA分析结果表明 ,1 30 0℃之前 ,试样中没有氮化物生成 ,物相为莫来石、石英和方石英 ;1 30 0℃时 ,高岭土开始发生氮化反应 ,生成过渡型SiAlON和β SiAlON。此时 ,石英和方石英相基本消失 ;1 4 0 0℃时 ,过渡型SiAlON、β SiAlON和X SiAlON三相共存 ,β SiAlON有所增多并有少量刚玉相生成 ;从 1 4 50℃到 1 550℃ ,Z值为 3的β SiAlON成为惟一的氮化产物 ,与少量SiC和刚玉相并存。莫来石在 1 50 0℃时完全消失 相似文献
56.
Fushe-Kruje水泥厂项目位于距阿尔巴尼亚首都地拉那市28公里处,是由黎巴嫩SEAMENT集团投资兴建的.是迄今阿尔巴尼亚最大的外商投资项目,设计能力为3300t/d新型干法水泥熟料生产线,是全套生产线由我公司设计、制造成套、施工、安装、调试及试生产的总承包项目。 相似文献
57.
The aluminated sepiolite, obtained by alkaline treatment with KAlO2, as well as the silver-exchanged aluminated sepiolite were tested in ethanol conversion. The reactions were performed at 280°C and with 50 Torr of ethanol in He. After the alumination through KA1O2, ethanol dehydrogenation and ethanol dehydration resulted from the Lewis acidity. The dispersion of silver led to a bifunctional catalytic system and the overall catalytic activity and the selectivity towards the acetaldehyde production increased. As a result of the Prins reaction, a significant yield in butadiene was observed. 相似文献
58.
Grace Y. Sun 《Lipids》1979,14(11):918-924
The phospholipid composition and their acyl group profiles from subcellular fractions of guinea pig adrenal gland and the
same fractions from the cortex and medulla of the bovine gland were compared. The phospholipids of guinea pig adrenal were
enriched in diacyl-glycerophosphocholines (GPC) which comprised over 50% of the total phospholipids, but the proportions of
ethanolamine and choline plasmalogens, sphingomyelin and diacyl-glycerophosphoserine (GPS) were lower in guinea pig adrenals
as compared to the bovine adrenals. In the bovine adrenal, sphingomyelin and diacyl-GPS were enriched in the medulla, whereas
diacyl-glycerophosphoinositol (GPI) were enriched in the cortex. Although lysolecithin was present (up to 4.5%) in the bovine
adrenal, only trace amounts of this lipid were detected in the guinea pig adrenal. Characteristic acyl group profiles were
found associated with each type of the phosphoglycerides in adrenal membranes. However, acyl group profiles of the phosphoglycerides
were not greatly different either between the bovine and guinea pig adrenal or with respect to the type of subcellular membranes
isolated. Diacyl-GPC were enriched in 16∶0 and 18∶1, but also contained considerable amounts of 18∶0, 18∶2 and 20∶4. Diacyl-GPE
were enriched in 18∶0, 18∶1 and 20∶4, while diacyl-GPI, diacyl-GPS, as well as alkenylacyl-GPE, were enriched in 20∶4. The
lysolecithin from bovine adrenal membranes contained mainly 16∶0, 18∶0 and 18∶1 with only trace amounts of the polyunsaturated
fatty acids. Other polyunsaturated fatty acids, such as 22∶4 and 22∶6, are apparently not prominent in the phosphoglycerides
from either the bovine or the guinea pig adrenal gland. 相似文献
59.
Chunnuan Ji Rongjun Qu Cheng Bo Cao Huo Chen Qiang Xu Changmei Sun Chunhua Wang Huafang Yuan Jun Zhou 《应用聚合物科学杂志》2006,102(6):6054-6059
A novel chelating resin containing sulfoxide and diethylene glycol, poly{4‐vinylbenzyl‐[2‐2‐(hydroxyethyl)ethoxyl]sulfoxide} (PVESO) was synthesized using chloromethylated polystyrene (PS‐Cl) as material. Its structure was characterized by elemental analysis, infrared spectra, and scanning electron microscopy (SEM). The adsorption capacities of the resin for Hg2+, Ag+, Cu2+, Zn2+, and Pb2+ at various pH values were determined. The maximum adsorption capacities for Hg2+ and Ag+ were 1.56 and 0.75 mmol g?1 respectively. The resin had high selectivity for Hg2+ and Ag+ over the pH range 1.0–7.0. The adsorption capacities for Hg2+ and Ag+ under competitive condition were also determined by batch experiment method. In addition, the adsorption kinetics of the resin towards Hg2+ at different temperatures was also investigated. The results showed that the adsorption rate was governed by film diffusion at 20°C and 25°C, by particle diffusion at 30°C and 35°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6054–6059, 2006 相似文献
60.