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901.
强直电流伸展弧CVD硬质合金金刚石涂层工具 总被引:1,自引:0,他引:1
采用自行研制的强电流直流扩展电弧设备对酸浸和渗硼预处理的YG6刀片进行了金刚石薄膜涂层沉积,并对放于不同位置的沉积刀片表面涂层的激光Raman谱和SEM形貌进行了分析、研究。结果表明:渗硼预处理工艺优于酸浸预处理工艺;在渗硼处理的GY6刀片上,沉积的金刚石薄膜涂层具有大面积、均匀性好和质量高的特点。 相似文献
902.
对加固环的受力分布情况进行了分析,用有限元法对其受力强度进行了数值计算。结果表明,加固环应该处于污水处理塔柱体与锥体的连接处,且加固环的横截面积A≥45cm^2时,即可保证污水处理塔工作的稳定性和安全性。 相似文献
903.
低碱度顶渣控制帘线钢中MnO-Al2O3-SiO2类夹杂物成分的实验研究 总被引:3,自引:0,他引:3
在实验室中使用高温管式炉对以工业纯铁为原料配制的帘线钢进行脱氧和顶渣熔炼,研究了顶渣成分对MnO-Al2O3-SiO2类夹杂物的成分的影响。结果表明,在顶渣碱度为0.7~1.36时,随着顶渣中Al2O3含量的增加,夹杂物中的Al2O3含量也随之增加,当顶渣中Al2O3含量低于8%时,MnO—Al2O3—SiO2类夹杂物的成分在塑性区范围,通过控制脱氧条件和项渣的成分可以把MnO-Al2O3—SiO2类夹杂物的成分控制在塑性区内的。 相似文献
904.
Tbe N - methylmorpholine - N - oxide (NMMO) - water solvent was used to dissolve the cellulose that was achieved by means of hydrothermolysis. Sample B, RS and WS used here were made from beech, rice straw and wheat straw respectively. They could be completely dissolved in the NMMO - water system. A commercial a - cellulose was employed in the comparative experiment. The entire dissolving process was Investigated. At a given temperature, the vacuum condition applied to the mixture of the cellulose and NMMO - water was very important in order to accelerate the dissolution of cellulose and shorten the dissolving period. After dissolution, degree of polymerization (DP) of all samples was measured by viscometry. Longer dissolving time and higher temperature could cause the degradation of the dissolved cellulose. N- propyl gallate could prevent the degradation of cellulose during the process of dissolution. 相似文献
905.
于伟东 《东华大学学报(英文版)》1999,(1)
It is well known that top dyeing is an Important step in wool processing, but it will result in the damage of fibre in normal dyeing. How to measure the damage quickly and to evaluate it quantitatively are vital important for wool industry and also interested for wool researchers. For the purpose, nineteen tops dyed in normal condition from three wool textile mills in China were tested with TENSOR, a bundle fibre tensile tester. The experimental results showed that the dyeing damage rate of bundle strength of these tops is 6% - 7% in average and some tops were higher than 10% dyeing damage. Meanwhile, the dyeing damages for different wool mills were discussed . It is obvious that bundle tensile test is an efficient and quick method to evaluate the damage caused by top dyeing and to identify the difference between wool mills in quality and quantity. 相似文献
906.
In this paper, the factors to influence the dynamic heat - moisture comfort of summer clothing fabrics have been studied. It is pointed out that, when the wind speed outside is high, or the air permeability is very good, the sweat of human body will evaporate mainly through turbulent diffusion. Because of the rapid sweat evaporation, human body will feel cold, and then, the difference in temperature and humidity of the micro - climatic section will be very slight. On the contrary, when the wind speed outside is slow or the air permeability is unsatisfactory, the sweat of human body will evaporate mainly through molecular diffusion, and in this case, the humidity of the micro - climatic section will be depended on the hygroscopicity of the fabric, that' s to say, the better the hygroscopicity, the lower the humidity. It is difficult for pure wool fabric to loss heat because of its giving out much heat during the course of moisture - absorption in the initial stages of sweating. For pure polyester fabric, 相似文献
907.
This paper described the physical behaviour of three types of denim cloths produced from rotor yarn, ring yarn and modified rotor yarn (prepared by adding conventional twist to rotor yarn) respectively. Experimental work showed that denim cloth produced from the modified rotor yarn has superior properties over conventional rotor yarn in terms of surface texture and appearance,tearing strength and resistance to abrasion. 相似文献
908.
This study attempted to examine the importance of storeenvironment in affecting consumers'store choice deci-sion;the relative importance among the three environ-mental factors;and consumers'expectations on store en-vironment for the casual-wear chain stores in HongKong.Julie Baker's Three-category framework onstore environments namely ambient,design and socialfactors was adopted for investigation.The results indi-cated that the store environment was important in affect-ing consumers'selection of store for shopping.It alsorevealed that social factor was perceived relatively im-portant than ambient and design factors.Nine store ex-pectation dimensions were categorised and the resultdemonstrated that most respondents were concerned onthe social aspect in their expectation of having a satisfy-ing store environment. 相似文献
909.
The aim of this study is to examine the buyer-seller re-lationship in Hong Kong's clothing industry.The initialpart investigated the industry's environment.Four hy-pothesis were developed which were based on the long-term buyer-seller relationships'features.The benefitsthat can enjoy within the stage of long-term buyer-seller relationships was the defined and suggested. 相似文献
910.
板式换热器中蒸汽凝结换热特性 总被引:11,自引:0,他引:11
在板式换热器的蒸汽凝结换热试验台上进行了实验研究,获取蒸汽完全凝结和部分凝结两种典型工况下的换热和压降特性.且就板式换热器中蒸汽凝结过程的换热进行分析和处理,得到了一个在板片槽道中蒸汽凝结换热系数关联式.并推荐用于板式换热器的蒸汽凝结换热系数的计算. 相似文献