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911.
针对石化行业挥发性有机物(VOCs)污染现状,总结了近年来我国国家层面和地方颁布的有关VOCs管控的法律法规及相关标准。通过调研石化行业现阶段VOCs控制的实际情况,总结了目前主要的控制技术,以及适合我国企业VOCs排放源的监测技术。在综合分析的基础上,提出了大力推进清洁生产、全面推行泄漏检测与修复(LDAR)计划、加强有组织工艺废气治理、严格控制储存与装卸损失、强化污水系统逸散废气治理、加强非正常工况污染控制等建议。  相似文献   
912.
铜离子广泛存在于环境和食品中,机体中游离铜离子含量增加可导致神经系统功能紊乱和肝、肾损害等。目前铜离子的检测方法主要有:原子吸收光谱法(AAS)、电感耦合等离子体原子发射光谱法(ICP-AES)和电感耦合等离子体质谱法(ICPMS),这些方法虽然检测结果准确、灵敏度高,但仪器昂贵、样品处理复杂且不能区分铜离子的存在形态。因此,探索基于铜离子特异性识别元件构建的荧光或电化学检测方法在游离铜快速特异性响应中的应用受到了广泛青睐,其对应的铜离子特异性识别元件如有机小分子、纳米材料、生物分子等亦得到了不断地丰富和发展。有机小分子设计灵活,纳米材料响应灵敏,生物分子特异性强、生物相容性好,此三者作为特异性识别元件在血清游离铜的检测中具有广阔的应用前景。  相似文献   
913.
Volatile organic compounds at swine facilities: A critical review   总被引:3,自引:0,他引:3  
Ni JQ  Robarge WP  Xiao C  Heber AJ 《Chemosphere》2012,89(7):769-788
Volatile organic compounds (VOCs) are regulated aerial pollutants that have environmental and health concerns. Swine operations produce and emit a complex mixture of VOCs with a wide range of molecular weights and a variety of physicochemical properties. Significant progress has been made in this area since the first experiment on VOCs at a swine facility in the early 1960s. A total of 47 research institutions in 15 North American, European, and Asian countries contributed to an increasing number of scientific publications. Nearly half of the research papers were published by U.S. institutions.Investigated major VOC sources included air inside swine barns, in headspaces of manure storages and composts, in open atmosphere above swine wastewater, and surrounding swine farms. They also included liquid swine manure and wastewater, and dusts inside and outside swine barns. Most of the sample analyses have been focusing on identification of VOC compounds and their relationship with odors. More than 500 VOCs have been identified. About 60% and 10% of the studies contributed to the quantification of VOC concentrations and emissions, respectively. The largest numbers of VOC compounds with reported concentrations in a single experimental study were 82 in air, 36 in manure, and 34 in dust samples.The relatively abundant VOC compounds that were quantified in at least two independent studies included acetic acid, butanoic acid (butyric acid), dimethyl disulfide, dimethyl sulfide, iso-valeric, p-cresol, propionic acid, skatole, trimethyl amine, and valeric acid in air. They included acetic acid, p-cresol, iso-butyric acid, butyric acid, indole, phenol, propionic acid, iso-valeric acid, and skatole in manure. In dust samples, they were acetic acid, propionic acid, butyric acid, valeric acid, p-cresol, hexanal, and decanal. Swine facility VOCs were preferentially bound to smaller-size dusts.Identification and quantification of VOCs were restricted by using instruments based on gas Chromatography (GC) and liquid chromatography (LC) with different detectors most of which require time-consuming procedures to obtain results. Various methodologies and technologies in sampling, sample preparation, and sample analysis have been used. Only four publications reported using GC based analyzers and PTR-MS (proton-transfer-reaction mass spectrometry) that allowed continuous VOC measurement. Because of this, the majority of experimental studies were only performed on limited numbers of air, manure, or dust samples. Many aerial VOCs had concentrations that were too low to be identified by the GC peaks.Although VOCs emitted from swine facilities have environmental concerns, only a few studies investigated VOC emission rates, which ranged from 3.0 to 176.5 mg d−1 kg−1 pig at swine finishing barns and from 2.3 to 45.2 g d−1 m−2 at manure storages. Similar to the other pollutants, spatial and temporal variations of aerial VOC concentrations and emissions existed and were significantly affected by manure management systems, barn structural designs, and ventilation rates.Scientific research in this area has been mainly driven by odor nuisance, instead of environment or health concerns. Compared with other aerial pollutants in animal agriculture, the current scientific knowledge about VOCs at swine facilities is still very limited and far from sufficient to develop reliable emission factors.  相似文献   
914.
对某铁合金厂2台硅铁矿热炉烟气参数进行了现场测量,测量结果表明,测点烟气温度偏低,流量偏大.通过对原始测量数据进行筛选整理,得到了更加真实的测量结果;通过分析测量数据,诊断出导致现有余热锅炉进口烟气温度偏低的主要原因,并给出相应的对策建议.  相似文献   
915.
916.
日本地震超高密度实时监测系统(SUPREME)建设中的核心技术之一是依据强震记录对液化场地进行反演识别,系统中目前使用的是Suzuki法,但实际应用效果并不理想。选取不同地震下多种类别场地上的实际地震记录,对Suzuki法的适用性进行了研究,讨论了其不同指标对不同类别场地识别结果的影响。分析表明:Suzuki法对不同类别非液化场地的识别能力不同,最显著的缺陷是易将软土场地与液化场地混淆;方法所使用的4个识别指标中,过零周期为控制参数,其它指标仅起到初判作用;方法出现误判的原因是液化场地的过零周期范围与非液化中软土场地上的过零周期范围存在明显交叉,而这一点理论上是无法避免的客观存在;改进的方法是应放弃现有进行绝对值对比的做法,改用地震动某些参数的相对变化作为新的识别指标。  相似文献   
917.
Biomonitoring of industrial chemicals in human tissues and fluids has shown that all people carry a “body burden” of synthetic chemicals. Although measurement of an environmental chemical in a person's tissues/fluids is an indication of exposure, it does not necessarily mean the exposure concentration is sufficient to cause an adverse effect. Since humans are exposed to multiple chemicals, there may be a combination effect (e.g., additive, synergistic) associated with low-level exposures to multiple classes of contaminants, which may impact a variety of organ systems. The objective of this research is to link measures of body burden of environmental chemicals and a “holistic” measure of wellness. The approach is demonstrated using biomonitoring data from the National Health and Nutrition Examination Surveys (NHANES). Forty-two chemicals were selected for analysis based on their detection levels. Six biological pathway-specific indices were evaluated using groups of chemicals associated with each pathway. Five of the six pathways were negatively associated with wellness. Three non-zero interaction terms were detected which may provide empirical evidence of crosstalk across pathways. The approach identified five of the 42 chemicals from a variety of classes (metals, pesticides, furans, polycyclic aromatic hydrocarbons) as accounting for 71% of the weight linking body burden to wellness. Significant interactions were detected indicating the effect of smoking is exacerbated by body burden of environmental chemicals. Use of a holistic index on both sides of the exposure-health equation is a novel and promising empirical “systems biology” approach to risk evaluation of complex environmental exposures.  相似文献   
918.
大气环境高灵敏光谱探测技术   总被引:1,自引:0,他引:1  
大气环境高灵敏光谱探测技术是以光与环境相互作用为基础发展起来的学科交叉方向,使用光学的方法和手段来探知研究环境问题。大气环境高灵敏光谱探测技术能够实现从现场瞬态灵敏探测到污染时空分布等不同尺度的遥测,从而获得大气污染"点-线-面"的时空变化规律,由于光谱探测技术具有多组分、非接触、无采样、高灵敏度、大范围快速以及遥测等特点,已经成为国际上大气环境监测技术的主要方向之一。大气环境高灵敏光谱技术在污染源、工业园区、空气质量以及区域污染等监测方面都有很广泛的应用。针对化工园区复杂的环境污染问题,光谱探测技术可以高灵敏、非接触地获取多种污染物浓度特征,掌握化工园区污染时空分布状况,为化工园区的大气污染治理提供有效支撑;针对京津冀、长三角等地区大气重污染过程的核心问题,大气环境高灵敏光谱探测技术通过地基组网观测,车载/机载平台移动观测等三维立体监测手段获取重点区域污染物的生成、转化过程以及重污染过程的形成机制,为区域大气污染成因追溯、污染控制措施评估提供科学的数据和技术支撑。高灵敏光谱探测技术在大气环境领域的成功应用,为污染源、化工园区和重点区域的环境综合诊断和治理奠定了技术基础。  相似文献   
919.
随着工业的迅速发展,迄今为止,已有大约10万种化学物进入人们的日常生活.人们在生产和生活中接触的许多种环境化学物都会影响人类的生殖功能,使人类的生育能力特别是精子的质量和数量发生显著改变.环境化学物所造成的生殖损伤日益受到人们的重视,检测方法和检测技术日益成熟和完善.但大多数环境化学物对生殖的损害目前尚未得到全面地研究和认识,某些毒物的生殖毒性也需要重新认识与评价,生殖毒理学的研究任务迫切而艰巨.动物实验是生殖毒性评价中最主要的方法.在总结近年来国内外相关研究基础上综述了环境化学物动物实验中雄(男)性生殖损伤评价指标及检测技术,以期对环境化学物生殖毒性评价提供借鉴和参考.  相似文献   
920.
Livestock manure is suitable for use as a composting material. However, various intestinal microbes, such as Escherichia coli, are significant components of such manures. Thus, it is desirable that the level of intestinal microbes, and particularly opportunistic pathogens, in compost is inspected and counted regularly. The sensitivity and specificity of detection of E. coli in compost have been improved by selective cultivation followed by colony polymerase chain reaction (PCR) using the ECO primer. Indeed, the sensitivity of this method is higher than that of DNA extraction from compost and PCR. In this study, changes in numbers of E. coli present in a field-scale composting process over time was assessed using selective cultivation and colony PCR. Numbers of ECO-positive colonies after 24 h decreased, with a concomitant rise in compost temperature. ECO-positive colonies were not detected from 33 to 48 h. However, ECO-positive colony numbers increased beginning on day 4 and continuing until day 42. Thus, it seems likely that the high temperatures reached during the composting process did not affect E. coli numbers in the final compost. Additionally, selective cultivation followed by colony PCR using specific primers is an appropriate method of determining levels of cultivable pathogens in composted materials.  相似文献   
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