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991.
Luxi Zou Huaibo Li Shuo Wang Kaikai Zheng Yan Wang Guocheng Du Ji Li 《Frontiers of Environmental Science & Engineering》2019,13(6):83
992.
Taner Güney 《国际发展与全球生态学杂志》2019,26(5):389-397
The purpose of the present study is to analyse the effects of renewable energy and non-renewable energy on sustainable development. This study is pioneering in this respect because it analyses the effect of renewable energy on adjusted net savings, which is a good sustainable development variable. For this purpose, the data of 40 developed and 73 developing countries were included. According to the estimation results obtained in the study, renewable energy has a positive and statistically significant effect on sustainable development both in developed countries and in developing countries. The impact of renewable energy on sustainable development is greater than the impact of non-renewable energy. In this respect, as the renewable energy amount increases, the level of sustainable development increases. According to these results, the fact that countries use renewable energy more than non-renewable energy sources is extremely important in terms of making progress towards sustainability of development and the 2030 Sustainable Development Goals. 相似文献
993.
994.
从非煤矿山矿井多风路排风系统、分风、控风、漏风、井巷风阻、节能扇风机等途径出发,分析了在这些方面开展通风节能的方法及其效益。 相似文献
995.
针对一般压力容器的爆炸情况,对容器内物质分3种集态分别讨论计算其爆炸能量、爆炸冲击波大小及其破坏范围,以此进行事故分析和后果预测。 相似文献
996.
反渗透(Reverse Osmosis,RO)因出水水质好、运行成本低等优势常用于垃圾渗滤液的处理,但产生的RO浓缩液具有COD高、色度高、盐分高、难降解等特点,其处理存在效果差、能耗和成本均较高等问题.本工作采用氧化钌/氧化铱涂层电极(RuO2/IrO2-Ti)的钛网为阳极,以304不锈钢电极为阴极,设计制作了6通道的电化学反应器,通过电化学氧化处理RO浓缩液,研究考查了电流密度、循环流速、比电极面积等参数对COD去除效果的影响,分析了电化学氧化去除难降解有机物并同时脱盐的过程机理与能耗.结果表明,在电流密度32.89 mA·cm-2,循环流速0.46 cm·s-1,比电极面积65.10 m2·m-3的条件下,电化学氧化处理RO浓缩液3 h,COD去除率可达68.0%,TOC去除率可达40.6%,脱盐率可达72.1%,去除单位质量COD能耗仅为常规的板状电极电化学反应器的25.5%.本工作可为垃圾渗滤液RO浓缩液的预处理提供新思路. 相似文献
997.
Fine root decomposition is an important way in which nutrients are returned to plantation soil; thus, further study of this process will be helpful for understanding material cycling in forest ecosystems. We investigated a Toona sinensis plantation in the central Sichuan hilly region using litter bags containing T. sinensis fine roots to evaluate the dynamics of fine root decomposition and nutrient release for one year in forest gaps of 50 m2 (L1), 100 m2 (L2), and 150 m2 (L3). The results showed that T. sinensis fine root decomposition was fastest in the first 90 days. As time passed, the decomposition rate slowed. One year later, the residue rate was 75.44%, 73.92%, and 72.07%, respectively. The fine root decomposition rate of L3 was greater than that of L2, which was greater than that of L1. During fine root decomposition, the dynamics of the fine root nutrient concentrations changed. C, P, and K concentrations of the fine roots declined in forest gaps, while N, Ca, and Mg concentrations increased overall in the fine roots. In conclusion, forest gaps had effects on the fine root decomposition and nutrient release of T. sinensis, and different sized forest gaps produced different results. © 2018 Science Press. All rights reserved. 相似文献
998.
Ksenya V. Mjachina Chris. W. Baynard Alexander A. Chibilyev Robert D. Richardson 《国际发展与全球生态学杂志》2018,25(6):541-553
Exploration and development of oil and gas (O&G) energy resources can create large-scale and permanent landscape effects that are best measured and understood via fieldwork and geospatial technologies. In this article, we examine O&G surface disturbance in the Orenburg steppe region of southwestern Russia for the year 2015. Utilizing field surveys, remote-sensing data and geographic information system (GIS) techniques, we apply a two-pronged approach. First, we map and measure the landscape infrastructure footprint (LIF) to determine the pattern and extent of direct surface disturbance created by O&G facilities and access roads. Second, we conduct a site suitability analysis to identify specific O&G production locations that are most vulnerable to environmental degradation. The approach considers both the particular properties of hydrocarbon production and specific natural features of steppe zones. Suitability patterns represent three indicators: two morphometric parameters (slope and aspect) and one spatial (the remoteness of O&G objects from water bodies). Our findings suggest that O&G production disturbs just over 3% of soil-vegetation cover in our study plot, while more than 13% of O&G objects are located in unsuitable zones based on topographic aspect, and about 11% lie in unsuitable zones regarding distance to water. 相似文献
999.
Urban energy consumption is one of the most important causes of air pollution. Air pollution-oriented ecological risk assessment is of great significance to the promotion of urban environmental protection. This paper focuses on ecological risk in Xiamen city caused by air pollutant discharge from urban energy consumption. The Long-range Energy Alternatives Planning model was used to establish two scenarios of energy consumption in Xiamen city, and based on different scenarios, we estimated urban energy consumption and discharge quantity of air pollutant (DQAP). A box model and an expert scoring method were used to calculate the air pollution burden (APB) of SO2, NO2, CO, PM10 and PM2.5 and to obtain the probabilities of different air pollution loads. An ecological risk assessment model was developed and utilized to predict Xiamen city’s ecological risks in 2020. The results showed that under an energy-saving scenario, the ecological risks for PM2.5, SO2 and NO2 are high, whereas the ecological risks for CO and PM10 are low. Under a baseline scenario, the ecological risks for PM2.5, SO2 and NO2 are moderate, whereas the ecological risks for CO and PM10 are low. In addition, the APB of SO2, NO2, CO, and PM2.5, but not of PM10, is predicted to rise. In the simulation, energy generation from coal is the main source of air pollution. Although the DQAP from automobiles is not high, it is predicted to rise year-on-year. In summary, the ecological risk due to pollution in Xiamen city is high, and the main pollutants are SO2, NO2 and PM2.5. 相似文献
1000.
我国农村能源政策以及收入水平对农户生活能源需求的影响研究 总被引:1,自引:1,他引:0
针对传统能源使用过程中产生的环境、气候问题,由中央政府制定并实施的农村能源政策倡导农户使用多种清洁能源及技术。同时,商品能源逐步成为当下农户生活能源的重要组成部分。“并举式”的能源政策是否造成甚至扩大不同能源、技术的需求差异,这一结果是否符合政策的初衷和目标?基于此,论文研究并分析2005—2014年农村能源政策以及收入水平对农户生活能源需求的影响。结果表明:政策的实施加剧了存在替代关系的能源、技术需求间的此消彼长;政策的溢出效应促进了部分商品能源需求;收入的提高对部分能源需求产生了正向作用。建议制定兼顾清洁能源以及商品能源的农村能源发展战略和政策,实现政策的精准发力,同时加强能源基础设施的建设和管理。 相似文献