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41.
Analytical Group of"August "Flood of YRCC 《人民黄河》1993,(8):1-5
“92.8”洪水位异常高的主要原因:一是前期连续几年枯水,造成河床严重淤积;二是本场洪水边滩淤积,河道过水面积减小。花园口站洪峰流量大于上站的主要原因是:主槽强烈冲刷,水位大幅度下降,漫滩水迅速回归主槽。 相似文献
42.
涤纶仿真丝绸深地防拔染印花──助拔剂的研究 总被引:1,自引:0,他引:1
Decharge Priceing Research Group 《丝绸》1995,(7)
阐述了涤纶仿真丝绸在高温高压染深地、以还原剂作为主拔剂的工艺中,其中助拔剂的分子结构对拔白性能的影响,并对其助拔机理进行了探讨。 相似文献
43.
Sumner S Brown LG Frick R Stone C Carpenter LR Bushnell L Nicholas D Mack J Blade H Tobin-D'Angelo M Everstine K;Environmental Health Specialists Network Working Group 《Journal of food protection》2011,74(2):215-220
This study sought to determine the frequency with which food workers said they had worked while experiencing vomiting or diarrhea, and to identify restaurant and worker characteristics associated with this behavior. We conducted interviews with food workers (n=491) and their managers (n=387) in the nine states that participate in the Centers for Disease Control and Prevention's Environmental Health Specialists Network. Restaurant and worker characteristics associated with repeatedly working while experiencing vomiting or diarrhea were analyzed via multivariable regression. Fifty-eight (11.9%) workers said they had worked while suffering vomiting or diarrhea on two or more shifts in the previous year. Factors associated with workers having worked while experiencing vomiting or diarrhea were (i) high volume of meals served, (ii) lack of policies requiring workers to report illness to managers, (iii) lack of on-call workers, (iv) lack of manager experience, and (v) workers of the male gender. Our findings suggest that policies that encourage workers to tell managers when they are ill and that help mitigate pressures to work while ill could reduce the number of food workers who work while experiencing vomiting or diarrhea. 相似文献
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卷烟厂设备三位一体化计算机管理系统将设备管理、维修管理和备件库存管理有机地结合为一个整体,实现了工作单管理、预防性设备维护、作业管理、库存管理、采购管理,以及关键及价格昂贵备件的库存和使用的全过程监控,并可灵活设置用户的使用权限,实现了全方位的计算机管理。该系统的使用可有效降低设备总体维护成本。 相似文献
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Lee R Beatty ME Bogard AK Esko MP Angulo FJ Selman C;EHS-NET Working Group 《Journal of food protection》2004,67(7):1444-1450
Salmonella enterica serotype Enteritidis (SE) is a common cause of foodborne illness in the United States. Foods prepared with raw shell eggs have often been associated with SE outbreaks. The federal government published the Egg Safety Action Plan in December 1999 that called for reduction of egg-preparation practices that may contribute to the survival and proliferation of SE. In seven states, an interview and brief site evaluation of 153 restaurants that prepare eggs during all hours of operation was conducted by the Environmental Health Specialists Network to determine the prevalence of such practices. Fifty-four percent (83 of 153) of restaurants pooled raw shell eggs not intended for immediate service. These pooled eggs were held a median of 4 h for scrambled eggs, 5.5 h for omelets, and 6 h for pancakes and French toast. Nearly 26% (39 of 152) of restaurants reported storing eggs at room temperature, and 5% (7 of 152) stored eggs on ice or in cold-water baths before cooking. Generally, eggs were cooked to 72 to 83 degrees C, which is above the recommended final cook temperature of 63 to 68 degrees C. Employees reported sanitizing utensils used to prepare eggs less than once every 4 h in 42% (57 of 136) of restaurants. Several areas were identified in which further emphasis might reduce egg-associated SE infections in accordance with Healthy People 2010 goals. 相似文献
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