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391.
Journal of Material Cycles and Waste Management - Leather production is a technology that boosts the economy because of its versatility and durability. However, the wastes generated throughout the...  相似文献   
392.
Journal of Material Cycles and Waste Management - The daily use of facemask to prevent virus transmission increases the negative effect on the environment because of improper waste disposal. Due to...  相似文献   
393.
In the Ohio River (OR), backwater confluence sedimentation dynamics are understudied, however, these river features are expected to be influential on the system’s ecological and economic function when integrated along the river’s length. In the following paper, we test the efficacy of organic and inorganic tracers for sediment fingerprinting in backwater confluences; we use fingerprinting results to evidence sediment dynamics controlling deposition patterns in confluences used for wetland and marina functions; and we quantify the spatial extent of tributary drainages with wetland and marina features in OR confluences. Both organic and inorganic tracers statistically differentiate sediment from stream and river end‐members. Carbon and nitrogen stable isotopes produce greater uncertainty in fingerprinting results than inorganic elemental tracers. Uncertainty analysis of the nonconservative tracer term in the organic matter fingerprinting application estimates an apparent enrichment of the carbon stable isotopes during instream residence, and the nonconservativeness is quantified with a statistical approach unique to the fingerprinting literature. Wetland and marina features in OR confluences impact 42% and 11% of tributary drainage areas, respectively. Sediment dynamics show wetland and marina confluences experience deposition from river backwaters with longitudinally linear and nonlinear patterns, respectively, from sediment sources.  相似文献   
394.
Weather variability has the potential to influence municipal water use, particularly in dry regions such as the western United States (U.S.). Outdoor water use can account for more than half of annual household water use and may be particularly responsive to weather, but little is known about how the expected magnitude of these responses varies across the U.S. This nationwide study identified the response of municipal water use to monthly weather (i.e., temperature, precipitation, evapotranspiration [ET]) using monthly water deliveries for 229 cities in the contiguous U.S. Using city‐specific multiple regression and region‐specific models with city fixed effects, we investigated what portion of the variability in municipal water use was explained by weather across cities, and also estimated responses to weather across seasons and climate regions. Our findings indicated municipal water use was generally well‐explained by weather, with median adjusted R2 ranging from 63% to 95% across climate regions. Weather was more predictive of water use in dry climates compared to wet, and temperature had more explanatory power than precipitation or ET. In response to a 1°C increase in monthly maximum temperature, municipal water use was shown to increase by 3.2% and 3.9% in dry cities in winter and summer, respectively, with smaller changes in wet cities. Quantifying these responses allows urban water managers to plan for weather‐driven variability in water use.  相似文献   
395.
Environmental Science and Pollution Research - Global warming is considered as the main environmental stress affecting ecosystems as well as physiological and biochemical characteristics, and...  相似文献   
396.
Environmental Science and Pollution Research - Dengue fever (DF) is one of the world’s most important vector-borne illnesses. In 2017, Egypt experienced a dengue outbreak. This study aimed to...  相似文献   
397.
研究了山西省4座典型焦炉周边环境空气中总悬浮颗粒物(TSP)碳组分特征,分析了不同装煤方式和炭化室高度对其的影响。结果表明:(1)焦炉周边环境空气中TSP质量浓度为711.95~2 938.41μg/m3,其中有机碳(OC)、元素碳(EC)的质量浓度分别为189.45~595.90、285.38~806.71μg/m3,总碳占TSP的质量分数为44.81%~67.45%;捣固焦炉周边的TSP及其碳组分浓度高于顶装焦炉,炭化室高度越高的焦炉周边环境空气中TSP及其碳组分浓度越低。(2)4座焦炉周边环境空气TSP中OC和EC质量比为0.66~1.04,说明焦炉周边环境空气中碳组分以一次污染为主。(3)4座焦炉周边环境空气TSP中碳组分的分歧系数为0.092~0.490,均小于0.5,总体来说装煤方式和炭化室高度都对焦炉周边环境空气TSP中碳组分的分布有一定影响,特别是装煤方式和炭化室高度都不同的焦炉周边环境空气TSP中碳组分差异较大。  相似文献   
398.
采用均匀型和蛋白型Ru/TiO_2催化剂为湿式氧化催化剂,应用于催化湿式氧化非达霉素提炼废水,以出水COD和TOC去除率作为指标来评价2种催化剂的催化活性差异;采用实验室连续评价装置对柱状颗粒催化剂在不同pH、不同废水流量和不同温度下处理非达霉素提炼废水进行了优化评价。结果表明:在265℃、pH=4.1、废水流量为10 mL·h~(-1)时,催化剂的催化活性最高,故确定此条件为该废水处理的最优条件;同时对比均匀型和蛋白型2种催化剂,蛋白型催化剂具有更高的催化效率;结合SEM及N_(2~-)物理吸附结果,推断蛋白型催化剂活性组分集中分布在催化剂颗粒的较浅层,有利于降低反应过程中的扩散阻力,提高贵金属活性组分的利用率,进而提高催化剂的催化活性。以上结果对开发高效湿式氧化催化剂,充分利用贵金属活性组分降低催化剂成本具有十分重要的意义。  相似文献   
399.
The present experiment was done to evaluate the impact of ambient air pollution on carrot (Dacus carotavar. Pusa Kesar) plants using open top chambers (OTCs) ventilated with ambient (NFCs) or charcoal filtered air (FCs) at a suburban site of Varanasi, India. Various morphological, physiological and biochemical characteristics of the plants were studied at different growth stages. Air monitoring data clearly showed high concentrations of SO2, NO2and O3in the ambient air of study site. SO2and NO2concentrations were higher during early growth stages of carrot, whereas O3concentration was highest during later growth stages. Filtration of air has caused significant reductions in all the three pollutant concentrations in FCs as compared to NFCs.Plants growing in FCs showed significantly higher photosynthetic rate, stomatal conductance, water use efficiency and variable fluorescence as compared to plants growing in NFCs. Protein content also showed a similar pattern, however, lipid peroxidation, ascorbic acid content and peroxidase activity were higher in plants growing in NFCs as compared to FCs. Shoot length, number of leaves per plant, leaf area and root and shoot weight increased significantly upon filtration of ambient air. Total nitrogen decreased significantly in root, but increased significantly in shoot of plants grown in NFCs. Total P, Mg, Ca and K contents decreased significantly in plants grown in NFCs as compared to FCs. The individual pollutant concentrations were below threshold for plant injury, but the combined effect of all the three seems to act synergistically in causing greater adverse impact on dry weight and physiology of carrot plants. The study clearly indicates that air pollutants are high enough in the ambient air to cause significant unfavorable impact on carrot plants. The work further supports the usefulness of OTCs for assessing air pollution damage under field conditions in developing countries.  相似文献   
400.
The distribution and composition of hydrocarbons in sediment from the Fladen Ground oilfield in the northern North Sea have been investigated. The total PAH concentrations (2- to 6-ring parent and alkylated PAHs, including the 16 US EPA PAHs) in sediments were relatively low (<100 microg kg(-1) dry weight). The PAH, the Forties crude and diesel oil equivalent concentrations were generally higher in sediment of fine grain size and higher organic carbon concentration. PAH distributions and concentration ratios indicated a predominantly pyrolytic input, being dominated by the heavier, more persistent, 5- and 6-ring compounds, and with a high proportion of parent PAHs. The n-alkane profiles of a number of the sediments contained small, high boiling point, UCMs, indicative of weathered oil arising from a limited petrogenic input. The geochemical biomarker profiles of the sediments that contained UCMs showed a small bisnorhopane peak and a high proportion of norhopane relative to hopane, indicating that there was contamination from both Middle Eastern and North Sea oils. Therefore contamination was not directly as a result of oil exploration activity in the area. The most likely source of petrogenic contamination was from general shipping activity.  相似文献   
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