小规模采矿立法和调整框架

虽然数量日益增长的第三世界国家正在它们各自的小规模采矿部门引进法律和规章，但是这些还不足以帮助促进部门发展，同时也无法解决与之相关的杜会和环境问题．这是由非政府组织中间技术实施的一项研究的一些主要调查结果，该项研究的资金来源于英国政府的国际发展部．这是一项对于小规模采矿立法的试点研究，同时其目的是为政府和援助机构提供可持续政策和调整机制的指南．     

历时1284天的艰难结案——北京东方化工厂"97·6·27"特大爆炸火灾事故结案始末

罕见的大事故 1997年7月1日,香港将告别一百多年的殖民统治回到祖国的怀抱. 1997年5月11日,国务院召开全国安全生产电视电话会议,国务院副总理吴邦国在电视电话会议上强调,现在距香港回归只剩下50多天,党的十五大也将召开,一定要做好安全生产工作,创造一个良好的气氛.     

用共沸蒸馏法测定土壤和植物中的苯、甲苯

地下储油罐的腐蚀、汽油的漫溢以及不适当的处置,使土壤和植物受到汽油中苯和甲苯的污染.本文采用甲醇萃取、共沸蒸馏技术来测定土壤和植物中的苯、甲苯.采用共沸蒸馏技术可避免色谱柱的污染,且灵敏度高.受汽油污染的土壤和植物样品采集后,应将土壤样品贮存在广口瓶里,植物样品应贮存在密封的塑料袋里.然后,把它们放在-12°下冷藏至分析.由于所用的甲醇试剂含有少量的极性杂质和醛、酮、干扰分析.因此,甲醇必须经过活性炭和硼酸钠处理.方法:将1升甲醇通过25cm长的活性炭柱(1.9×30cm),除去干扰杂质.然后用慢速过滤纸进行过滤,除去能吸附芳香族化合     

某石油化工企业100万吨连续重整装置职业病危害的控制效果

为识别某化工企业在建设项目在试运行期间可能产生的职业病危害因素,评价其防护措施及其控制效果。通过对现场进行职业卫生学调查、职业病危害因素检测和收集职业健康监护相关资料,定性、定量地进行综合评价。结果显示:该总体布局、生产工艺及设备布局、建筑卫生学、个体防护用品、应急救援措施、辅助用室等方面符合标准、规范要求。该项目属于职业病危害严重的项目,该项目职业病危害控制措施可行、有效,但需要加强对氨的职业病危害控制措施。     

基于文本挖掘的城镇燃气事故致因及关联分析

为有效预防城镇燃气事故发生,采用文本挖掘与复杂网络理论相结合的方法,系统分析影响城镇燃气安全的事故致因及其关联性。首先运用文本挖掘技术,从2017—2021年间的1 256份燃气事故案例中提取城镇燃气事故致因因素,采用Apriori算法挖掘城镇燃气事故致因的关联规则,共得到49条强关联规则;然后基于共现矩阵构建事故致因网络图,通过度中心性、紧密中心性、介数中心性分析,明确燃气事故的关键致因项和事故致因集合。研究结果表明：管道破损,阀门未关,设备老化,操作、使用不当和软管破损、脱落是城镇燃气事故关键致因因素,气体泄漏是燃气事故常见的事故类型,主要与管道破损、阀门未关等具有强关联性。     

Magnesium-rich minerals in sediment and suspended particulates of South Florida water bodies: implications for turbidity

Fine sediments in shallow water bodies such as Lake Okeechobee are prone to resuspension. Predominantly inorganic "mud" sediment that covers approximately 670 km2 of the lake has been recognized as a persistent source of turbidity. The objective of this study was to determine if mineral components of sediments in Lake Okeechobee and water conveyances of the northern Everglades also occur as suspended sediment and hence constitute a potential abiotic contributor to turbidity. Sediment samples were collected from nine stations within the lake and eight locations north of Water Conservation Area 2A in the Everglades. Water samples were also collected at selected locations. The silt and clay mineralogy of sediment and suspended particles was determined using X-ray diffraction, thermogravimetry, scanning-electron microscopy, energy-dispersive X-ray elemental microanalysis, and high-resolution transmission-electron microscopy. Clay fractions of the lake sediment contained the Mg silicate minerals sepiolite and palygorskite, along with smectite, dolomite, calcite, and kaolinite. Sediment silt fractions were dominated by carbonates and/or quartz, with smaller amounts of Ca phosphates and sepiolite. Mineralogy of the mud sediment was similar to that reported for geologic phosphate deposits. This suggests that the mud sediment might have accumulated by stream transport of minerals from these deposits. Suspended solids and mud-sediment mineralogy were similar, except that smectite was more abundant in suspended solids. Everglade samples also contained Mg-rich minerals. The small size, low density, and fibrous or platy nature of the prevalent mud sediment minerals make them an abiotic, hydrodynamically sensitive source of persistent turbidity in a shallow lake. Mitigation efforts focused exclusively on P-induced biogeochemical processes do not address the origin or effects of these minerals. Ecological management issues such as turbidity control, P retention, geologic P input, and suitability of dredging are related to mud-sediment properties and provenance.     

磁絮凝法处理DZA有机废水的研究

本文介绍了磁絮新颖产分离技术，应用该技术能有效处理水中ＤＺＡ有机物，实现数秒内的快速分离污泥，污泥含水率低。