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61.
薄型聚酯非织造布热轧工艺的探讨 总被引:3,自引:0,他引:3
探讨了薄型酯非织造布在生产过程中,其热轧机温度、压力、速度等工艺参数的设定对产品强力、抗弯刚度、折皱弹性的影响。 相似文献
62.
本文叙述了湿法成网非织造布生产特点和湿法成网过滤材料的生产实践,探讨了纤维性能对过滤材料的影响因素和解决方法,对湿法与干法非织造布滤材的性能进行了比较,并指出了目前湿法滤材生产中存在的问题,提出了相关的建议。 相似文献
63.
煤矿采准巷道所处围岩条件较差,巷道变形破坏受自然因素和开采技术因素影响。该文探讨了采准巷道合理的布置位置,从而改善巷道受力状况,保证巷道安全可靠使用。 相似文献
64.
This article posits that practitioners in some geographical jurisdictions may be at greater risk for losing their livelihood, savings, and health because of the practices of their licensing boards. Several examples of questionable actions by licensing boards are cited, and a rationale for greater compassion, support, and advocacy for colleagues is offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
A novel moire optical interference method, originally developed1 to measure the swelling displacement normal to the plane of a simple butt joint during water uptake at the joint edge, was subsequently used to investigate the unexpected occurrence of shrinkage and, at the same time, swelling during exposure to organic solvents. In later experiments, synergistic displacement fields generated during simultaneous exposure to water and organic solvents were studied. The same method has also been used to investigate the origin of adhesion failures at copper plated-through holes in thermally cycled multi-layer circuit boards. The method employs a thin glass cover slip as one adherend. Changes in bondline thickness flex the cover slip thereby changing the gap between the latter and a nearby optical flat. By using monochromatic light to illuminate the specimen, interference between incident and reflected light is achieved. The small displacements of individual fringes associated with changes in gap size are used to generate moire patterns which bear a 1:1 relationship to the local changes in bondline thickness. Application of thin plate elasticity theory to the flexing of the cover slip yields the stress acting normal to the joint. The magnitude of this normal stress is strongly inhomogeneous, oscillating in sign and reaching compressive values as high as 50MNm?2 for water uptake by a simple butt joint, and exceeding the yield strength of oxygen-free high conductivity copper (1MNm?2) for the thermal expansion that accompanies simulated soldering of a multi-layer circuit board. Attention is drawn to the high resolution achievable with the method. Changes in bond-line thickness of the order of Δ/10, where Δ is the wavelength of the light giving rise to the interference pattern, are readily resolved. It is pointed out that the method may well be sufficiently sensitive to detect the effects of different physical properties (thermal conductivity, specific heat capacity) of adherend surface on the nature of the cured adhesive and hence on the mechanical behaviour of the bond-line. 相似文献
66.
Extensive laboratory investigations and mill scale trials confirmed the applicability of ultrafiltrated high molecular weight Ca-ligno-sulfonates in adhesive composition with phenolic resin for insulation board manufacture based on mineral wool. Insulation materials produced with adhesive components with a formulation of lignosulfonate/PF resin between 10/90 and 30/70 have appropriate technical and commercial properties. 相似文献
67.
针对高层民用建筑消防联动控制系统设计存在的一些问题,通过对消防规范的理解、分析、探讨,提出相应的技术措施,力求消防联动控制系统的设计更加完善。 相似文献
68.
69.
探讨了合同管理工作是企业管理工作的一项重要的内容,在合同订立、签订、履行以及纠纷及时处理几方面尽到注意义务是企业做好合同管理工作的前提基础。 相似文献
70.
No authorship indicated 《Canadian Metallurgical Quarterly》2003,58(8):627
Lists the officers, boards, committees, and representatives of the American Psychological Association for 2003. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献