PPPUE模式及在中国的应用前景探讨

PPPUE是一种全新的应对城市环境问题的模式,这种模式的应用能够充分发挥公共部门、私人部门和第三方的各自优势。本文总结了这种模式的发展过程与基本运作模式,并对PPPUE模式在我国应用的现状、面临的问题以及应用前景作了分析探讨,为解决我国的城市环境问题提供了一种思路。     

Synthesis and application of Cu-BTC@ZSM-5 composites as effective adsorbents for removal of toluene gas under moist ambience: kinetics,thermodynamics, and mechanism studies

Metal organic frameworks (MOFs) are excellent adsorbents that provide abundant specific surface area, adjustable pore structure, and rich active sites. The purpose of this study was to prepare composites with hydrophobic and high microporous specific surface area and to adsorb toluene gas in moist ambience. An ethanol activation-assisted hydrothermal method was proposed to synthesize copper-benzene-1,3,5-tricarboxylic acid (Cu-BTC) metal-organic framework, Cu-BTC, and ZSM-5 molecular sieve composites (Cu-BTC@ZSM-5). The dynamic adsorption process of toluene on different adsorbents was investigated, and the results showed that the toluene adsorption capacity of Cu-BTC@ZSM-5 (158.6 mg/g) was 2.53 times higher than Cu-BTC (62.7 mg/g), when the ZSM-5 content is 5% and the humidity is 30%RH. Compared with other factors, the humidity inhibited the adsorption of toluene on Cu-BTC@ZSM-5. Langmuir model and the pseudo-second kinetics model can better describe the adsorption behavior of Cu-BTC@ZSM-5. The thermodynamic results showed the adsorption process was a spontaneous exothermic process at low temperature and mainly physical adsorption. The relative regenerability can still up to 80.4% after six cycles. The adsorption mechanisms of Cu-BTC@ZSM-5 were pore-filling adsorption, π-π interaction, cation-π bonding, and hydrophobic interactions. This study will help to design a systematic route to evaluate the adsorption performance of Cu-BTC@ZSM-5 for toluene.

     

Modeling the non-linear relationship between financial development and energy consumption: statistical experience from OECD countries

The linkage between financial development and energy consumption is widely investigated in the literature. However, the non-linear relationship between financial development and energy demand is still under debate. Therefore, this study aims to examine the non-linear relationship between financial development, economic growth, and energy consumption in OECD countries. The study uses the Driscoll–Kraay standard errors panel regression model for spanning from 1980 to 2016. The empirical findings indicate that an inverted U-shape relationship exists between financial development and energy consumption as well as between economic growth and energy consumption. Moreover, the feedback hypothesis is found between financial development and energy use. Additionally, income and energy use granger cause each other. The innovative findings contribute to extant literature, which is of special interest to the country’s policymakers regarding energy efficiency.

     

Analysis of the decoupling effect and eco-economic coordination of the resident energy carbon footprint: a case study of Caijiapo Town,a national key town in western China

Environmental Science and Pollution Research - National key towns are one of the most important units for mitigating China’s carbon emissions from urbanisation, industrialisation and...     

Resource-based cities (RBC): a road to sustainability

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.     

A New Screening Measure to Identify Potential Carbon Monoxide Hotspots

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.     

CAST工艺在制革废水处理中的应用

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。     

Impacts of Social and Demographic Factors on Residents’ Subjective Well-being in Rural China

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.     

Research on the exploitation and utilization degree of mineral water based on ecological base flow in the Changbai Mountain basalt area,northeast China

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...     

Highly efficient catalytic reduction of 4-nitrophenol and organic dyes by ultrafine palladium nanoparticles anchored on CeO2 nanorods

Environmental Science and Pollution Research - Uniformly dispersed Pd nanoparticles on certain supports exhibit exceptional catalytic performance toward various environmental applications. In this...