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621.
• Physical and chemical properties and application of peracetic acid solution. • Determination method of high concentration peracetic acid. • Determination method of residual peracetic acid (low concentration). Peroxyacetic acid has been widely used in food, medical, and synthetic chemical fields for the past several decades. Recently, peroxyacetic acid has gradually become an effective alternative disinfectant in wastewater disinfection and has strong redox capacity for removing micro-pollutants from drinking water. However, commercial peroxyacetic acid solutions are primarily multi-component mixtures of peroxyacetic acid, acetic acid, hydrogen peroxide, and water. During the process of water treatment, peroxyacetic acid and hydrogen peroxide (H2O2) often coexist, which limits further investigation on the properties of peroxyacetic acid. Therefore, analytical methods need to achieve a certain level of selectivity, particularly when peroxyacetic acid and hydrogen peroxide coexist. This review summarizes the measurement and detection methods of peroxyacetic acid, comparing the principle, adaptability, and relative merits of these methods.  相似文献   
622.
Environmental Science and Pollution Research - Currently, sustainable utilization, including recycling and valorization, is becoming increasingly popular in waste management. Black soldier fly...  相似文献   
623.
Environmental Science and Pollution Research - While nitrogen (N2) fixation is an important process in nitrogen (N) biogeochemical cycling, supplying a significant portion of the N in natural...  相似文献   
624.
Environmental Science and Pollution Research - The combustion of fossil fuels has resulted in rapidly increasing emissions of nitrogen oxide (NOx), which has caused serious human health and...  相似文献   
625.
Environmental Science and Pollution Research - In this study, a composite aerogel (WP-MMT) composed of wastepaper (WP) and montmorillonite (MMT) was prepared by ambient pressure drying technology...  相似文献   
626.
Environmental Science and Pollution Research - Soil labile and recalcitrant carbon (C) and nitrogen (N) are strongly controlled by plant inputs and climatic conditions. However, the interrelation...  相似文献   
627.
近年来,配电网中分布式能源、电动汽车等负荷的接入率越来越高,配电网的网络架构和功能趋于复杂,在电网运行中带来不少问题。基于泛在电力物联网的新形势下,对宁夏宁东地区分布式电源、电动汽车等负荷的接入以及宁东基地用户侧的用电特点进行分析,提出主动配电网建设的思路及初步治理措施,对宁东地区“十四五”电网规划建设具有一定的现实意义和参考价值。  相似文献   
628.
通过分析杨房沟水电站料场开挖爆破粉尘的粒度分布特征,为改进爆破降尘工艺提供粉尘粒度学依据。在料场爆破区、工作平盘、出入沟、最终边帮等处采集粉尘样品,采用激光粒度分布仪测试粉尘样品的分散度;以粉尘粒度分布数据拟合分布函数,表明爆破粉尘的粒度分布函数呈现对数正态分布特征;与经典的罗森·拉姆勒(Rosin?Rammler)分布函数模型对比分析表明,对数正态分布函数用于描述爆破粉尘的粒度分布更加准确。基于对数正态分布函数模型,厘定爆破粉尘粒度分布参数,分析TSP、PM10、PM5、PM2.5及PM1粉尘占全尘的比例,定量表达爆破粉尘粒度分布特征。结果表明:杨房沟水电站料场爆破粉尘具有显著的对数正态分布特征;离爆破中心距离越远,粒度分布范围越窄,对人体有害粉尘占比越大;建议采用爆破粉尘捕捉吸附技术、掺和湿润性抑尘剂的水雾喷洒等降尘措施。  相似文献   
629.
This work investigated water samples collected from Tapeng Lagoon, Taiwan. Factor analysis was conducted to explain the characteristics and the variation in the quality of water during the disassembly of oyster frames and fishery boxes. The result shows that the most important latent factors in Tapeng Lagoon are the ocean factor, primary productivity factor, and the fishery pollution factor. Canonical discriminant analysis is applied to identify the source of pollution in neighboring rivers outside Tapeng Lagoon. The two constructed discriminant functions (CDFs) showed markedly contribution to all discriminant variables, and that total nitrogen, algae, dissolved oxygen and total phosphate, combined in the nutrient effect factor. The recognition capacities in these two CDFs were 95.6%, 4.4%, respectively. The water quality in the Kaoping river most strongly determined that in the Tapeng Lagoon the best is. And disassembling the oyster frames and fishery boxes improves the water quality markedly. However, environmental topographic conditions indicate that strengthening stream pollution prevention and to constructing another entrance to the ocean are the best approaches for improving the quality of water in Tapeng Lagoon, especially by reducing eutrophication. These approaches and results yield useful information concerning habitat recovery and water resource management.  相似文献   
630.
Using clean lab methods and protocols developed for measuring Sb in polar snow and ice, we report the abundance of Sb in fifteen brands of bottled water from Canada and forty-eight from Europe. Comparison with the natural abundance of Sb in pristine groundwaters, water bottled commercially in polypropylene, analyses of source waters prior to bottling, and addition of uncontaminated groundwater to PET bottles, provides unambiguous evidence of Sb leaching from the containers. In contrast to the pristine groundwater in Ontario, Canada containing 2.2 +/- 1.2 ng l(-1) Sb, 12 brands of bottled natural waters from Canada contained 156 +/- 86 ng l(-1) and 3 brands of deionized water contained 162 +/- 30 ng l(-1); all of these were bottled in PET containers. Natural water from Ontario bottled in polypropylene contained only 8.2 +/- 0.9 ng l(-1). Comparison of three German brands of water available in both glass bottles and PET containers showed that waters bottled in PET contained up to 30 times more Sb. To confirm that the elevated Sb concentrations are due to leaching from the PET containers, water was collected in acid-cleaned LDPE bottles from a commercial source in Germany, prior to bottling; this water was found to contain 3.8 +/- 0.9 ng l(-1) Sb (n = 5), compared with the same brand of water purchased locally in PET bottles containing 359 +/- 54 ng l(-1) (n = 6). This same brand of water in PET bottles, after an additional three months of storage at room temperature, yielded 626 +/- 15 ng l(-1) Sb (n = 3). Other German brands of water in PET bottles contained 253-546 ng l(-1) Sb (n = 5). The median concentration of Sb in thirty-five brands of water bottled in PET from eleven other European countries was 343 ng l(-1) (n = 35). As an independent check of the hypothesis that Sb is leaching from PET, the pristine groundwater from Canada (containing 2.2 +/- 1.2 ng l(-1) Sb) was collected from the source using PET bottles from Germany: this water contained 50 +/- 17 ng l(-1) Sb (n = 2) after only 37 days, even though it was stored in the refrigerator, and 566 ng l(-1) after six months storage at room temperature.  相似文献   
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