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191.
为了解决"双迫"型废火药的处理和再利用问题,提出了一种制备射钉弹用球扁型发射药的新工艺.工艺过程包括将经过粉碎的原料药粒分散到含有分散剂的水溶液中,加入适量的乙酸乙酯溶剂使药粒表层溶胀,在搅拌剪切力和界面张力的作用下,药粒的表面发生球形化转变,再经过洗涤、分级和烘干等处理,得到表面光滑的球扁药.研究得到的适宜工艺条件为溶剂比1.0~2.0 ml·g-1,用水量为药粒的6.0倍,分散剂用量为水量的1.0%~2.0%,搅拌速率500~600 r·min-1(线速度4.0~5.0 m·s-1),溶胀温度和时间分别为65~68 ℃和30 min.成品球扁药的堆积密度由0.70 g·cm-3提高到0.95 g·cm-3以上,流出时间由7.5 s下降到4.0 s以下.在射钉枪上进行测试,其主要弹道性能达到PATMI标准的规定指标. 相似文献
192.
为深入分析燃煤锅炉尾部受热面低温腐蚀的机理,找到尾部余热深度利用的可行之法,本文从低温腐蚀原理、硫酸露点及其凝结形成机理出发,根据我国实际情况,分析比较了国内外使用的预防低温腐蚀、降低排烟温度、高效回收排烟余热的技术、设备及方法的优缺点,结合有效腐蚀理论,指出锅炉尾部烟气余热深度利用的研究方向。 相似文献
193.
采用树脂法从柠檬酸废醪中提取食用色素—焦糖色素和黄色素。产品质量分别达到国家标准,同时使排放废液的COD由10~14万mg/l降至1万mg/l左右,pH由4.5~5.0升至7.0左右 相似文献
194.
195.
OBJECTIVE: To describe the waste produced by and environmental implications of individual cigarette consumption (filter tips, packages, and cartons) and tobacco manufacturing. STUDY SELECTION: All available articles and reports published since 1970 related to cigarette consumption and production waste were reviewed. DATA SOURCES: Global cigarette consumption data were used to estimate cigarette butt and packaging waste quantities. Data from the Center for Marine Conservation's International Coastal Cleanup Project were used to describe some environmental impacts of tobacco-related trash. Data from the United States Environmental Protection Agency's (EPA's) Toxics Release Inventory and reported global cigarette consumption totals were used to estimate waste production from cigarette manufacturing. DATA EXTRACTION AND SYNTHESIS: In 1995, an estimated 5.535 trillion cigarettes (27,675 million cartons and 276,753 million packages) were sold by the tobacco industry globally. Some of the wastes from these products were properly deposited, but a large amount of tobacco consumption waste ends up in the environment. Some is recovered during environmental clean-up days. For the past eight years (1990-1997), cigarette butts have been the leading item found during the International Coastal Cleanup Project; they accounted for 19.1% of all items collected in 1997. The tobacco manufacturing process produces liquid, solid, and airborne waste. Among those wastes, some materials, including nicotine, are designated by the EPA as Toxics Release Inventory (TRI) chemicals. These are possible environmental health hazards. In 1995, the global tobacco industry produced an estimated 2262 million kilograms of manufacturing waste and 209 million kilograms of chemical waste. In addition, total nicotine waste produced in the manufacture of reduced nicotine cigarettes was estimated at 300 million kilograms. CONCLUSIONS: Laws against littering relative to cigarette butts could be better enforced. Additional taxes might be levied on cigarette products that would then be directed to environmental clean-up efforts. The tobacco industry should improve the biodegradability of filters, reduce packaging waste, and educate its customers. Worksites and public buildings should be encouraged or required to supply appropriate disposal mechanisms at all building entrances. Public awareness campaigns about the magnitude and prevention of cigarette consumption waste could be developed through partnerships among environmental groups, health organisations, and environmental protection agencies. Tobacco production waste should be a source of concern and regulation by governments throughout the world; it contains numerous chemicals which may be considered health hazards, not the least of which is nicotine produced in the manufacture of low-nicotine cigarettes. 相似文献
196.
文章阐述了微滤膜在电路板废水方面的应用,并将其与传统的斜板沉淀及现行的超滤系统进行了比较,突出了微滤系统在电路板废水回用方面的优势。 相似文献
197.
冯源 《电子产品可靠性与环境试验》2007,25(3):42-45
指出了企业在实施ISO 14001:2004过程中可能存在的问题,并针对固体废物管理、MSDS编写、文件之间不一致、轻污染企业的误区等问题给出了相应的解决方法. 相似文献
198.
199.
Sugam Sharma Ritu Shandilya U. Sunday Tim Johnny Wong 《Telematics and Informatics》2018,35(2):446-456
Hunger is a global crisis and impacting the world for a very long time. Significant efforts have been made in the past by various organizations employing various means to address this persisting problem. Despite this, it still remains far from being resolved. Recently, the United Nations has published a report on global hunger, which claims that the global food production is fairly enough to feed the entire world with a population of about 7.3 billion. However, a major quantity of the food grown is not channeled appropriately and effectively to reach the needy and thus gets wasted unfortunately. Using the advanced computer technologies, we devise and develop a web-based computational framework (eFeed-Hungers.com) that serves as a bridge between the food waste and the hunger to mitigate the hunger issue; the food waste is the excess, unused, edible food, which otherwise is destined to the dumpster unfortunately. The eFeed-Hungers.com encourages and assists the food waste donation announcements with the least minimal efforts with the best possible outreach. Through the eFeed-Hungers.com, the food donations are globally searchable by the needy, with enough additional information imparted for quick decisions making to fetch the appropriate donated food. The eFeed-Hungers.com is envisioned to be a fully functional organization eventually with global outreach. 相似文献
200.
环境保护和污染控制是建设生态型发射场的重要组成部分.分析了中国航天发射场的环境污染,针对推进剂四氧化二氮泄漏提出了采用钙基高活性粉剂处理技术,介绍了研制的系列处理装置,提出了臭氧-紫外光-活性炭联合工艺处理推进剂废水和高温燃烧处理推进剂废气废液技术,研制了移动式处理装置,解决了常规液体推进剂的发射环境污染难题,为航天发... 相似文献