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接近发动机排气歧管位置的催化转化器由于其最大限度地发挥了催化剂的效能,被欧IV排放标准的车辆广泛应用。本文介绍这种催化转化器的结构和试验验证过程,包括试验目的、试验方案、失效模式、试验参数的确定等等,给出了确定加速耐久性试验的循环次数方程。 相似文献
3.
Adhesional shear strength and chemical composition at the Si/EVA interface of samples extracted from a PV module manufactured by a major manufacturer using slow-cure EVA and deployed in the hot and humid climate at Cocoa, FL were studied. Precipitation of sodium from glass superstrate and ambient, and phosphorous from dopant glass reduced adhesional strength at Si/EVA interface to 35% of that in new modules. Presence of tin at this interface has also been attributed to solder-bond corrosion by moisture and impurities Na and P. It is interesting to point out that in this case, corrosion has occurred prior to delamination. 相似文献
4.
Müyesser Selda Tözüm 《纺织学会志》2013,104(9):1203-1212
In this study, it was focused on the investigation of comfort-related properties of the fabrics treated with microcapsules containing phase change materials (PCMs microcapsules). There are limited findings about the effect of prepared PCM microcapsules on fabric properties related with the tactile comfort. In this work, we applied our produced microcapsules to the cotton fabrics and researched these fabrics’ tactile comfort-related properties such as bending rigidity, drape, fabric–fabric friction, and tenacity. One of the outstanding properties of our microcapsules is reactive carboxylic acid groups on their wall. They have the ability to bind to the fabrics in terms of their reactive chemical groups. Microcapsules on the fabrics can be durable to the effects of the rubbing and repeated washings. The fabric test results indicated that air permeability, bending rigidity, tensile strength decrease with the microcapsule treatment, whereas the fabric drape and coefficient of friction of the fabrics increase depending on the amount of microcapsules added on the fabric. 相似文献
5.
文章通过对五种不同原料双罗纹针织物服用性能进行综合分析,得出含有Viloft纤维的针织物及涤/粘针织物具有较好的服用舒适性。 相似文献
6.
玄武岩纤维织物耐酸碱性试验研究 总被引:1,自引:0,他引:1
对一种国产玄武岩纤维织物的耐酸碱性进行了试验,研究了在33~35℃温度下0.5、1.0mol/L的盐酸溶液及0.5、1.0mol/L氢氧化钠溶液中经不同时间的腐蚀后三种规格的玄武岩纤维织物力学性能的变化。结果表明,该玄武岩纤维织物有很好的耐酸碱性,力学性能较稳定,且织物的耐酸性能优于其耐碱性能,证实了玄武岩纤维织物能够在酸碱环境下长期使用,尤其是酸性环境下。 相似文献
7.
针对目前电动钉枪质量体系建立的现状,开发针对电动钉枪耐久性研究的系统,新开发的系统提供了电动钉枪耐久性测试和电动钉枪最高工作频率判断的功能,同时也可以对电动钉枪的耐久性研究提供试验平台。重点分析了如何运用威布尔分布对耐久性试验数据进行处理。 相似文献
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9.
Nehru Chevanan Kasiviswanathan Muthukumarappan Kurt A. Rosentrater 《Food and Bioprocess Technology》2009,2(2):177-185
Three isocaloric (3.5 kcal/g) ingredient blends containing 20, 30, and 40% distiller-dried grains with solubles (DDGS) along
with 5% whey were prepared with a net protein content adjusted to 28% (wet basis [wb]). Other ingredients in the blends included
soy flour, corn flour, fish meal, vitamin, and mineral mix. These blends were extruded in a single-screw extruder at 15, 20,
and 25% (wb) moisture content and at 130 and 160 rpm screw speeds. Compared to previous research, the durability and unit
density of the extrudates in this study were found to increase substantially by the addition of whey to the blends. Increasing
the DDGS content from 20 to 40% resulted in a 5.8 and 16.8% increase in extrudate moisture content and redness, respectively,
but produced a decrease of 11.2% in brightness and 3.6% in yellowness of the extrudates. Increasing the moisture content of
the ingredient blends from 15 to 25% resulted in an increase of 16.1, 8.7, and 9.3% in moisture content, durability, and redness,
respectively, but a decrease of 9.8 and 5.6%, respectively, in brightness and yellowness of the extrudates. Neither DDGS level
nor screw speed significantly affected extrudate durability or unit density. In fact, changing the screw speed had no significant
effect on many of the properties of the extrudates studied, except for moisture content, redness, and yellowness. As demonstrated
in this study, ingredient moisture content and screw speed are critical considerations when producing extrudates with feed
blends containing DDGS; further work is needed to optimize processing conditions and to produce floating feeds. 相似文献
10.
某工程屋面板开裂事故的分析与处理 总被引:2,自引:0,他引:2
论述了某单层工业厂房屋面板开裂的状况、原因分析和处理情况 ,同时对混凝土的质量控制和外加剂的使用 ,提出了建议 ,可供设计和施工人员参考 相似文献