环境工程中大气污染危害与治理方案的解读

当前,随着我国社会工业化水平的不断提升,工业化企业在市场中得到了快速的发展.但是,由于工业化企业在生产的过程中,产生了大量的污染气体,严重破坏了我国大气环境质量,导致我国大气环境污染问题越加的严重,许多大城市中经常会出现雾霾等环境问题,严重影响到了人们的生活质量,甚至对社会的稳定发展也造成了严重的影响.大气污染问题对人...     

纺织行业中多环芳烃的危害及其替代研究

多环芳烃(PAHs)一般存在于煤、煤焦油和原油等自然物质中,而一些人为因素也会使环境中产生多环芳烃化合物。在纺织行业中,多环芳烃主要用作生产染料的基本原料,同时也广泛存在于橡胶制品和塑料制品中。由于PAHs具有潜在的毒性和致癌、致畸变性,并且它可以在生物体内累积和在食物链中传递,因此给环境和人类健康带来极大的威胁。PAHs对环境的污染已经引起了全世界的关注,很多国家均对消费品中PAHs的含量进行了严格的限制。主要介绍了PAHs的危害、法规要求及其在纺织行业中替代品的研究动态。     

Silage review: Animal and human health risks from silage

Silage may contain several agents that are potentially hazardous to animal health, the safety of milk or other animal food products, or both. This paper reviews published literature about microbial hazards, plant toxins, and chemical hazards. Microbial hazards include Clostridium botulinum, Bacillus cereus, Listeria monocytogenes, Shiga toxin-producing Escherichia coli, Mycobacterium bovis, and various mold species. High concentrations of C. botulinum in silage have been associated with cattle botulism. A high initial concentration of C. botulinum spores in forage in combination with poor silage fermentation conditions can promote the growth of C. botulinum in silage. The elevated pH level that is generally associated with aerobic deterioration of silage is a major factor influencing concentrations of L. monocytogenes, Shiga toxin-producing E. coli, and molds in silage and may also encourage survival and growth of M. bovis, the bacterium that causes bovine tuberculosis. Soil is a major source of B. cereus spores in silage; growth of this bacterium in silage appears to be limited. Hazards from plant toxins include pyrrolizidine, tropane and tropolone alkaloids, phytoestrogens, prussic acid, and mimosine, compounds that exist naturally in certain plant species that may contaminate forages at harvesting. Another group of toxins belonging to this category are ergot alkaloids, which are produced by endophytic fungal species in forages such as tall fescue grass, sorghum, and ryegrass. Varying effects of ensiling on the degradation of these plant toxins have been reported. Chemical hazards include nitrate, nitrite, and toxic oxide gases of nitrogen produced from nitrate and high levels of butyric acid, biogenic amines, and ammonia. Chemical and microbiological hazards are associated with poorly fermented silages, which can be avoided by using proper silage-making practices and creating conditions that promote a rapid and sufficient reduction of the silage pH and prevent aerobic deterioration.     

Organic Food: Buying More Safety or Just Peace of Mind? A Critical Review of the Literature

Consumer concern over the quality and safety of conventional food has intensified in recent years, and primarily drives the increasing demand for organically grown food, which is perceived as healthier and safer. Relevant scientific evidence, however, is scarce, while anecdotal reports abound. Although there is an urgent need for information related to health benefits and/or hazards of food products of both origins, generalized conclusions remain tentative in the absence of adequate comparative data. Organic fruits and vegetables can be expected to contain fewer agrochemical residues than conventionally grown alternatives; yet, the significance of this difference is questionable, inasmuch as actual levels of contamination in both types of food are generally well below acceptable limits. Also, some leafy, root, and tuber organic vegetables appear to have lower nitrate content compared with conventional ones, but whether or not dietary nitrate indeed constitutes a threat to human health is a matter of debate. On the other hand, no differences can be identified for environmental contaminants (e.g. cadmium and other heavy metals), which are likely to be present in food from both origins. With respect to other food hazards, such as endogenous plant toxins, biological pesticides and pathogenic microorganisms, available evidence is extremely limited preventing generalized statements. Also, results for mycotoxin contamination in cereal crops are variable and inconclusive; hence, no clear picture emerges. It is difficult, therefore, to weigh the risks, but what should be made clear is that 'organic' does not automatically equal 'safe.' Additional studies in this area of research are warranted. At our present state of knowledge, other factors rather than safety aspects seem to speak in favor of organic food.     

基于multi-agent的煤矿水害演化模型

根据矿区的水文地质条件,分析了煤矿水害事故的形成原因和演化机制,采用复杂系统理论和多主体建模方法,建立了煤矿水害演化模型;利用NetLogo仿真平台,对不同类型水害事故进行仿真模拟,动态表现煤矿水害演化过程以及影响因素之间的脆弱性关系。研究表明：煤矿水害是一种受控于多种因素、具有非线性动力特征的复杂自适应现象,只有了解矿区水文地质条件,并将复杂系统理论和多主体建模方法引入水害防治研究中,才能从本质上描述水害演化机制。     

斯蒂芬酸铅的静电危险性研究

为研究斯蒂芬酸铅(LTNR)的静电危险性,对其静电积累量和静电火花感度进行了全面的测试。选用不锈钢、铝、夹布胶木、导电胶皮和虫胶漆牛皮纸5 种滑槽,测试了不同滑槽长度和倾斜角度下LTNR 的下滑时间和静电积累量。计算出LTNR 与5 种滑槽的摩擦系数;研究了LTNR 的静电积累量随滑槽长度和倾斜角度的定量关系,分别拟合为线性方程和二次方程;研究了LTNR 的下滑速度和摩擦力对静电积累量的影响,并进行了二元线性回归,得出预估公式。此外,在不同的电容、电阻和极针间隙装置条件下,测试了LTNR 的静电火花感度。结果发现:测试条件对静电火花感度的测试结果影响较大,静电火花感度E50与极针间隙表现出正线性关系。     

FOX-7合成过程中硝化反应的热危险性

利用全自动反应量热器(RC1e)测定了1,1-二氨基-2,2-二硝基乙烯(FOX-7)合成过程中的硝化反应热释放速率及传热系数、比热容。结果表明硝化反应加料过程中的平均放热速率约为80 W,保温反应过程中的平均放热速率约为40 W,物料放热量为375.22 kJ·mol-1,理论绝热温升为483.8 K。采用差示扫描量热法(DSC)和热重-微商热重(TG-DTG)法分析了中间体2-(二硝基亚甲基)-5,5-二硝基嘧啶-4,6-二酮的热稳定性,其分解分为两个阶段,起始分解温度为30℃,第一阶段分解峰温为67.01℃,放热量为201.2 J·g-1;第二阶段分解峰温为87.15℃,放热量为1046.6 J·g-1,表明中间体的热稳定性较差。     

地下矿山微震响应空间探测概率特征与数据补偿方法

深部复杂地质环境高强度开采造成煤岩动力灾害频发,但地下矿山微震监测台网在数据探测完整性仍存在不足,极大增加了灾害预警的误报漏报风险。因此,将地震学中基于概率的完整性震级评价方法 (PMC)应用于某井工煤矿,分析了各微震台站的震动波拾波能力,探究了台网对采场微震响应探测概率的空间分布特征,并提出了基于探测概率的微震活动补偿方法。结果表明：相比于地震学中经典的最小完整性震级评价,PMC具有不依赖古登堡-里克特关系、计算简单、评价精度高的特点,更适用于地下矿山台网布置受限、震源来源复杂、震动波高噪音、强衰减的微震监测环境。微震台站对震动波的拾波能力受其所在区域采动煤岩体环境影响,对不同距离、不同能级微震事件的拾波概率具有显著差异：震源与台站距离越短、震源能级越高,台站对震动波到时标定的概率则越大。微震台网对微震事件的探测能力与震源能级直接相关,探测概率受台站布置影响在采场空间呈现高度非均匀分布特征。针对微震台网探测数据不完整的问题,提出了基于探测概率的微震活动补偿方法,还原了超前工作面煤体微震能级与频次的空间分布特征,其高能释放区域所在超前巷道位置与动力显现频发区域基本吻合,验证了采场微震数据补偿结果的有效性。研究成果可为地下矿山高质量微震监测与高效灾害防治提供理论与数据基础。     

计及主设备时变状态的变电站短时风险评估方法

传统的变电站风险评估以主设备年平均故障率计算主接线可靠性,不能反映设备时变故障风险及其对负荷点供电的影响.将主设备的运行风险考虑为设备自身状态和外部运行气象环境方面因素的影响,以比例风险模型量化设备运行风险.考虑到基于故障树的设备状态评分的分散性较大,不同部件故障对设备故障停运的影响程度不一样,建立了基于层次分析法的设...     

基于物联网的地质灾害自动化实时监测体系设计与实践

通过物联网技术实现地质灾害各监测要素的物物相连,实现前端报警、无线互联互通功能,建立地质灾害监测预警平台,实现专业监测数据具备部、省、市、县四级信息互联互通的功能实时共享;使监测预警信息实时发送至隐患点防灾责任人、监测责任人和监测人,以指导一线防灾工作高效开展;并在自贡市荣县一匹山崩塌预警过程中取得了重要成效,具有很强的参考价值。