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231.
介绍用气相色谱法定量分析对氯苯甲醛含量.该法操作简便、快速、定量准确,数据重视性好.本法的变异系数不大于0.40%,其回收率为99.7%~101.3%. 相似文献
232.
研究了聚酯超细纤维的染色动力学和热力学,主要包括不同线密度纤维的上染速率、半染时间、扩散系数、平衡吸附量、亲和力、染色热和染色熵等参数。同时对超细纤维的显色性和提升性与普通纤维进行了比较。分析了超细纤维不同于普通纤维的原因。 相似文献
233.
In this paper, the adsorption isotherms of two disperse dyes, C.I. Disperse Red 60 and C.I. Disperse orange 76, on two kinds of PU fibers at 90℃ were measured respectively. It was found that these adsorption isotherms followed a dual model, Nernst and Langmuir. Based on the parameters obtained in studying, the relationship between the chemical structure of dyes and their adsorption behaviors was arialyzed. Through the measurement of washing fastness of dyed sample with two dye concentrations, 1% (o.w. f) and 3% (o. w. f), it was found that the pale shade dyeing possessed better wet-fastness than the dark. This phenomenon confirmed further that the disperse dyes were sorbed on the PU fiber by langmuir sorption and the partition mechanism. 相似文献
234.
阐明了几种双折射滤波片在准连续染料激光器中的调谐特性,得到了适用于该类激光器单片双折射滤波片的性能参数. 相似文献
235.
ZHANG Shunli ZHOU Jingfang ZHANG Zhijun DU Zuliang A.V. Vorontsov JIN Zhensheng 《科学通报(英文版)》2000,45(16)
Morphological structure and physicochemical properties of nanotube TiO2 were investigated. It was found that the TiO2 nanotube consisted of 2-5 monolayers of TiO2 molecules, and its inner diameter was between 4.2 and 5.9 nm. The nanotube TiO2 powder had high specific surface area and pore volume (379 m2/g and 1.431 cm3/g respectively) and its decolorization activity for Reactive Brilliant Red X-3B was 2 times higher than that of raw TiO2 (p-25). This new type of TiO2 was hopeful for application in photocatalysis and composite nanomaterial. 相似文献
236.
使用新合成的氧化偶氮染料对定向和拉伸的聚乙烯醇薄膜染色,制备了具有较高偏振度和耐高温高温性能的偏振片。探讨了染色工艺对偏振片单片透过率和偏振度的影响,并通过正交试验确定了最佳染色工艺。在此染色条件下制备偏振片在单片透过率为40%左右时,偏振度可达到95%以上。 相似文献
237.
The dyeing deference between the superfine and the con-ventional polyester fabric is discussed. The major threefactors affecting the level dyeing property of superfinepolyester-initial adsorption rate, desorption rate andinterface migration rate of dyestuffs at 70℃ are studied.The levelness improves considerably with decreased ini-tial adsorption rate, increased desorption rate and inter-face migration rate. And then a mathematical indexbased on them is established. The evaluation to dispersedyes resulting from it corresponds with their perfor-mance during industrial process. As new definitions, ini-tial adsorption rate and desorption rate of dyestuffs arefirstly introduced. 相似文献
238.
绿色染料的开发不仅适应生态环保可持续发展的需要,也符合染料新功能的要求.本文对偶氮染料的危害和环保型染料的现状与发展进行综述,并介绍环保型染料的十条判别原则,和详细阐述新型环保型酸性染料的现状和发展动向,并充分阐明这些新开发染料的绿色和高性能特点,为印染企业选择和使用环保型染料提供了参考. 相似文献
239.
着重研究了还原桃红R染料铁离子的去除工艺,通过比较认为化学去除法中只有EDTA法可使铁离子含量达到规定的标准。 相似文献
240.
J. D. Huizinga L. W. C. Liu M. G. Blennerhassett L. Thuneberg A. Molleman 《Cellular and molecular life sciences : CMLS》1992,48(10):932-941
The functioning of a group of cells as a tissue depends on intercellular communication; an example is the spread of action potentials through intestinal tissue resulting in synchronized contraction. Recent evidence for cell heterogeneity within smooth muscle tissues has renewed research into cell coupling.Electrical coupling is essential for propagation of action potentials in gastrointestinal smooth muscle.Metabolic coupling may be involved in generation of pacemaker activity. This review deals with the role of cell coupling in tissue function and some of the issues discussed are the relationship between electrical synchronization and gap junctions, metabolic coupling, and the role of interstitial cells of Cajal in coupling. 相似文献