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61.
锦纶66浸胶帘子布生产中的张力与控制   总被引:2,自引:0,他引:2  
分析了帘子布生产中张力的作用及各区段的张力情况。张力应根据生产品种及浸胶帘子布的内在质量要求来选择,一般张力设定依据为拉伸区张力是干燥区张力的1倍,定型区张力是拉伸区张力的0.65倍。同时应控制好各区段的温度,降低拉伸应力使锦纶66帘子布拉伸均匀,提高帘子布的物理性能。  相似文献   
62.
孙莹  杨树莹  杨林军 《化工进展》2019,38(5):2491-2498
利用自行搭建的CO2膜吸收实验台,采用聚丙烯(PP)膜组件,以质量分数10%的N-甲基二乙醇胺(MDEA)作为主体胺溶液,添加不同配比的哌嗪(PZ)、乙醇胺(MEA)、甘氨酸钾(PG),考察CO2脱除效率和传质速率的变化,比较不同复配比的复合溶液表面张力以及对PP膜的浸润性,并以10%MDEA+10%PG混合溶液作为吸收液进行长时间实验。结果表明:添加少量的添加剂对MDEA溶液膜吸收CO2均有显著的促进作用,当配比小于0.2时,促进作用大小为PZ>MEA>PG;当配比大于0.2时,促进作用大小为PZ>PG>MEA;PZ和MEA均随着添加配比的增加,溶液表面张力减小,而PG相反;表面张力小的溶液对膜浸润性较强,容易造成膜润湿;添加剂质量分数均为10%时,对膜溶胀性和疏水性以及膜孔结构影响大小为PZ>MEA>PG;在20天内,PG/MDEA混合溶液作用下的CO2脱除效率从89.56%下降为83.09%,对PP的疏水性影响较小,膜组件可以稳定运行。吸收液表面张力对膜吸收法脱除CO2性能的影响显著。所得结果可为膜吸收CO2吸收剂复配提供依据,并可为揭示膜吸收CO2过程中膜润湿导致膜失效的机理以及抑制膜润湿提供实验数据。  相似文献   
63.
A number ofcis andtrans quatenary ammonium salts were synthesized from jojoba oil. All derivatives were found to be surface active agents, i.e., they reduced the surface tension to 35 dynes/cm−1, at very low concentrations. The relationship between the surface activity and the molecular structure is discussed.  相似文献   
64.
CCFW的一种新型张力控制方法研究   总被引:3,自引:0,他引:3  
通过一个实例介绍了计算机控制缠绕机(CCFW)的一种缠绕纤维的张力控制方法,着重分析了其技术要求与难点,并给出了最终的实现方法。这种方法对于造纸,纺织工业设备及其他缠绕设备的张力控制都极具参考价值。  相似文献   
65.
耿皎  洪梅  肖剑  张志炳 《化工学报》2002,53(6):600-606
选用 6种代表性物系对陶瓷板波纹和不锈钢丝网规整填料进行全回流精馏实验 ,考察Marangoni效应对规整填料液体流动分布及传质的影响 .结果表明 :对纯有机体系 ,Marangoni效应影响较小 ;而对有机物的水溶液 ,Marangoni效应严重影响着填料的润湿和传质效率  相似文献   
66.
On the Predominant Electron-Donicity of Polar Solid Surfaces   总被引:2,自引:0,他引:2  
The reasons for the predominant electron-donicity of almost all solid polar surfaces and its implications are discussed in this paper. By contact angle or interfacial tension measurements, the electron-accepting as well as the electron-donating properties of polar liquids can be ascertained, through the interplay between their energies of adhesion and cohesion. For the solid-liquid interface, direct interfacial tension measurements are not possible, but indirectly, solid/liquid interfacial tensions of polar systems can be obtained by contact angle measurement. However, as the energy of cohesion of a solid does not influence the contact angle formed by a liquid drop placed upon its surface, one can only measure the solid surface'ks residual polar property, manifested by the energy of adhesion between solid and liquid. This residual polar property is of necessity the dominant component; in most cases this turns out to be its electron donicity. When, by means of contact angle measurements with polar liquids, both electron-accepting and electron-donating potentials are found on a polar solid, it is most likely still partly covered with a polar liquid: usually water. The amount of residual water of hydration of a polar solid follows from its polar (Lewis acid-base) surface tension component (γAB). The degree of orientation of the residual water of hydration on a polar solid can be expressed by the ratio of the electron-donating to electron-accepting potentials (γ), measured on the hydrated surface.  相似文献   
67.
首次利用龙江县硅灰石研制出了高压电瓷 ,并测试了其晶相组成和性能。实验结果表明 :硅灰石可以用于生产高压电瓷 ,且硅灰石的加入量为 5 0 %左右时 ,高压电瓷的性能较佳  相似文献   
68.
By means of contact angle measurements on dry layers of electrostatically neutral dextran with pure water (pH 6.1), water acidified with HCl (to pH 1.94) and water made alkaline with NaOH (to pH 12.8), it could be shown that there was essentially no change as a function of pH in the ratio of γ+- of water as compared with the aqueous acid and alkaline solutions. (Here γ+ is the Lewis acid parameter of the polar surface tension component of water and γ- is its Lewis base parameter). In contrast, with contact angles measured with the same liquids on negatively charged clean glass, a significant decrease in contact angle was observed with water at pH 12.8, which was caused by the fact that at this alkaline pH an increase in surface hydrophilicity took place. This is because surfaces that have a given surface electrical potential at neutral pH generally acquire an even higher surface potential under more alkaline conditions which, concomitantly, also gives rise to an increase in surface hydrophilicity, and thus to lower contact angles with water. Finally, contact angles with acid water, pure water, and alkaline water, deposited on hydrophobic Parafilm surfaces, were exactly the same.  相似文献   
69.
The shape of interfaces formed by the contact of two liquid phases, immiscible with each other, and a gaseous phase can be predicted on the condition that the tension to work at each interface is known with a sufficient accuracy. In general, interfacial tension data available are not so accurate, however, as to be useful as they are in predicting the shape of interfaces, particularly when the spreading coefficient of either liquid (liquid 1) on the other (liquid 2) has a negative value of a small magnitude. Presented in this note is a simple method to rectify the interfacial tension data, with the aid of a measurement of the radius of a lens of liquid 1 of a known volume placed on the horizontal surface of liquid 2, and thereby make them usable for predicting interfacial geometries. The method is tested by applying it to benzene/water and n-pentane/water systems.  相似文献   
70.
The treatment of cotton or polyester fabric in alkali media is a common modification process for producing a fabric with desirable qualities. Alkali treatment of polyester/cotton fabric could produce a fabric with better performance. In this research, polyester/cotton fabric was treated with NaOH at different temperatures and times. The results show that alkali treatment at the optimum temperature and time with NaOH could hydrolyze the polyester fiber surface and remove some of the impurities from the cotton fiber at the same time and may also improve some of the fabric properties, such as fabric regain, water drop absorbency, and fabric pilling. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:5049–5055, 2006  相似文献   
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