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831.
Resource-based cities (RBC) have made momentous contributions to urbanization in China. However, as natural resources are exhausted, RBC are facing an enormous challenge. In this paper we put forward a resource-based city sustainability index (RCSI) and a resource-based city coordination index (RCCI), including environmental, social, and economic dimensions, adopted three weight scenarios, and selected 13 cities for study. The results: (a) help locate the problems by analyzing both dimensions and indicators; (b) simulate the trends of how RBC emerged, grew, declined, and regenerated; (c) categorize RBC into four types by integrating RCSI and RCCI; (d) give policy makers a holistic and comprehensive perspective in the future urban regulation and management; and (e) highlight a road to sustainability.  相似文献   
832.
ABSTRACT

To demonstrate conformity of transportation projects to National Ambient Air Quality Standards in accordance with State Implementation Plans, the U.S. Environmental Protection Agency (EPA) uses intersection level of service (LOS) as one of its major criteria for screening for potential carbon monoxide (CO) hotspots. Although intersection LOS is a measure of traffic volume, signal timing, and related congestion and delay, the assigned level reflects only the computed averaged stopped delay (ASD) per vehicle at the intersection. Thus, intersections can often operate at the same LOS but produce vastly different levels of predicted CO concentrations. For example, a two-lane approach operating at LOS D will produce very different levels of CO than a five-lane approach also operating at LOS D.

This study explores the effectiveness of the LOS D criterion as a screen for identifying potential CO hotspots. The study results indicate that LOS is a poor predictor of potential CO hotspots when compared to results generated with the EPA-recommended micro-scale model CAL3QHCr. To more consistently screen out those intersections that will not be identified as CO hotspots using the micro-scale models, a new criterion, equivalent red-time vehicles (ERTV), is introduced. The modeling results using ERTV suggest that it is a more robust measure for identifying potential CO hotspots, and conversely, screening out those intersections that are not likely to be identified as hotspots using micro-scale simulation results.  相似文献   
833.
CAST工艺在制革废水处理中的应用   总被引:1,自引:0,他引:1  
皮革生产企业由于污染严重,污水处理工艺简单、设备落后,最终出水各项指标超标,对环境造成严重污染。CAST工艺处理制革废水,反应条件在缺氧和厌氧之间变化,活性污泥通过酶的作用,不断经历高负荷的基质积累和低负荷的基质降解过程,迅速吸附降解污水中大部分可溶性有机物,抑制丝状菌的生长,有效地防止污泥膨胀,并达到脱氮、除磷的目的。运行结果表明,当进水BOD5为960~1250 mg/l,CODcr为2250~2780mg/l,出水达到《污水综合排放标准》(GB8978-1996)二级标准。  相似文献   
834.
Abstract

The objective of social development is to construct a harmonious society. In China, the key to a harmonious society is the happiness of more than 900 million farmers living in the rural areas. This study aimed to measure rural residents’ subjective well-being (SWB) through the day reconstruction method, as well as to analyze SWB’s influencing factors through a variety of statistical methods. The results showed that the average U index was 12.79%, indicating that respondents were unhappy 12.79% of the time. Twenty-seven percent of the population had a U index greater than 0, with the average value being 47%, indicating that these people were unhappy 47% of the time. The study also found that SWB varied according to the characteristics of the respondents. Logistic regression analysis showed that social and demographic factors, including age, education, county, household size, generation number, per capita income, migration status and social networking, which significantly affected rural residents’ SWB. The size of the impact varied with the different factors.  相似文献   
835.
Environmental Geochemistry and Health - Mineral water from the Changbai Mountain basalt area is China's most important source of drinking water. Mineral water with abundant output and enriched...  相似文献   
836.
Environmental Science and Pollution Research - Uniformly dispersed Pd nanoparticles on certain supports exhibit exceptional catalytic performance toward various environmental applications. In this...  相似文献   
837.
Environmental Science and Pollution Research - As a commonly used amendment to soil contaminated by heavy metals, biochar has attracted great attention and has been applied for decades due to the...  相似文献   
838.
Environmental Science and Pollution Research - The presence of heavy metal and organic pollutants in wastewater effluents, flue gases, and even solid wastes from petrochemical industries renders...  相似文献   
839.
Environmental Science and Pollution Research - While intensive peach production has expanded rapidly in recent years, few studies have explored the environmental impacts associated with specific...  相似文献   
840.
Environmental Science and Pollution Research - Radioactive iodine in nuclear waste is increasingly harmful to the human body and the environment because of its strong radioactivity, high fluidity,...  相似文献   
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