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791.
钟钢  曹丽君  贾玮 《四川环境》2010,29(5):82-86
通过对工业园区低碳发展模式的评估,分析其低碳发展的能源特征、经济特征与人力特征,并确定工业园区二氧化碳减排的潜力能源。基于能源-碳减排(EC)、经济-能源-碳减排(EEC)和人力-经济-能源-碳减排(HEEC)三种不同情景,在未来发展的一定规划期内,对工业园区具有二氧化碳减排潜力的能源进行规划分析,确定其年递减率,从而实现工业园区不同情景下的二氧化碳减排。通过实际案例研究,证明了评估与规划分析模型的可行性。  相似文献   
792.
    
In this modern age of industrialization, waste from houses and factories has a major impact on the environment, and its management has become one of the most difficult tasks for the whole world. This study attempts to locate suitable sites for disposing of solid waste using geospatial techniques in Ranchi, Jharkhand. Moreover, as Ranchi is a part of the smart city project, it is important to find new sites for dumping to control the environmental issue that arises due to the increasing pressure of population growth and the rate of human migration. Site selection of solid waste dumping considers several parameters, such as land use, land cover, road, geomorphology, soil, slope, water bodies, forest, and built-up. The present study has taken a multicriteria decision approach and used the analytical hierarchy process (AHP) to delineate the suitable landfill site for the medium-sized city of Ranchi. The study adopts the overlay analysis operation for several factors and geospatial techniques to perform site suitability analysis. The result shows four classes of suitable dumping sites, where low or restricted area covers 1145.52 km2 (63.92%), moderately restricted covers 477.74 km2 (26.65%), whereas about 140 km2 (7.81%) of the area can be constructed but with restrictions, and 28.79 km2 (1.60%) of the area is highly recommended for dumping site construction. The site suitability map and the identified four new dumping sites are highly useful to the municipality corporation and decision-makers to alleviate environmental pollution and human health problems.  相似文献   
793.
    
Plastics offer several benefits, such as durability, versatility, and cost-effectiveness, which have led to their pervasive use in nearly every aspect of modern life. However, their widespread use has led to significant environmental concerns. One of the major issues is their persistence in the environment, where they accumulate and cause contamination. This problem is particularly severe with plastic packaging and microparticles used in cosmetic products. As a result, the cosmetics industry started producing environmentally sustainable glitter. “Biodegradable” glitter is available in distinct compositions, mainly with a central base composed of a biodegradable material. This review focuses on academic research and patents related to glitter and biodegradable glitter, aiming to classify and compare commercially available options. Furthermore, this review analyzes scientific research on conventional glitter and its conclusions regarding environmental impact. For this, we used the keywords “glitter,” “biodegradable glitter,” “eco-friendly glitter,” “natural glitter,” and “sustainable glitter” in the databases of Wiley, Science Direct, Springer, and Clarivate Analytics ISI—Web of Science. We also performed a bibliometric analysis using the keyword “glitter” in the Web of Science database to obtain a bibliometric map of publication trends in the field using VOSviewer software. The products identified in the search were analyzed for their components and biodegradation potential. These products were classified as “biodegradable” if they were composed entirely of biodegradable constituents and as “eco-friendly” if only a portion of their constituents was biodegradable. We observed that several glitter products are incorrectly classified as biodegradable, demonstrating the need for standardized terminology that accurately reflects the composition of the glitter particles. Patent applications indicate a growing interest in developing environmentally safe glitter particles in recent years. Studies on conventional glitter mainly focus on its environmental impact or discuss analyzes for the identification and classification of glitter particles. The data gathered highlight the gaps in the field, mainly related to glitter production methods and the standardization of biodegradable glitter. Thus, studies in this direction are highly necessary.  相似文献   
794.
为解决当前气化炉供料系统风险分析不完善的状况,提出1种基于贝叶斯网络和HAZOP的风险分析模型。以某单日投煤量3 000 t级气化炉煤化工企业实际运行情况为研究对象,应用HAZOP法对其进行风险分析,并将HAZOP分析结果中各偏差产生原因转化为贝叶斯网络节点;考虑到先验知识的缺乏问题,引入Leaky Noisy OR模型,通过文献资料和相关领域专家经验知识获得先验概率,并利用贝叶斯网络进行风险分析,找出系统运行的薄弱环节。结果表明:未知因素影响会使各节点的后验概率值差异性降低,更加贴合实际;在引入未知因素影响后,系统运行薄弱环节并未发生改变。  相似文献   
795.
结合总体节能目标,对秦皇岛市“十二五”期间的能源需求进行了预测,并对三大产业能源利用形式及能源利用比例进行了分析。结果表明,第二产业的能源消耗比重最大,将成为节能总量控制的重点,而重中之重则是其中的工业领域节能。测算并分析了工业领域的节能潜力,范围涵盖玻璃制造、装备制造、粮油食品制造、金属压延业、建材、电力、化工7个主要行业。  相似文献   
796.
    
ABSTRACT: Devils Hole is a collapse depression connected to the regional carbonate aquifer of the Death Valley ground water flow system. Devils Hole pool is home to an endangered pupfish that was threatened when irrigation pumping in nearby Ash Meadows lowered the pool stage in the 1960s. Pumping at Ash Meadows ultimately ceased, and the stage recovered until 1988, when it began to decline, a trend that continued until at least 2004. Regional ground water pumping and changes in recharge are considered the principal potential stresses causing long term stage changes. A regression was found between pumpage and Devils Hole water levels. Though precipitation in distant mountain ranges is the source of recharge to the flow system, the stage of Devils Hole shows small change in stage from 1937 to 1963, a period during which ground water withdrawals were small and the major stress on stage would have been recharge. Multiple regression analyses, made by including the cumulative departure from normal precipitation with pumpage as independent variables, did not improve the regression. Drawdown at Devils Hole was calculated by the Theis Equation for nearby pumping centers to incorporate time delay and drawdown attenuation. The Theis drawdowns were used as surrogates for pumpage in multiple regression analyses. The model coefficient for the regression, R2= 0.982, indicated that changes in Devils Hole were largely due to effects of pumping at Ash Meadows, Amargosa Desert, and Army 1.  相似文献   
797.
本文从我国石油能源短缺和汽车尾气污染环境加剧的背景出发,详细分析了目前主要的各种新能源汽车的特点及在我国发展的前景,最后得出乙醇汽车应是我国发展新能源汽车的最佳选择的结论。  相似文献   
798.
ABSTRACT: When nonparametric frequency analysis was performed on 183 stations from Ontario and Quebec, unimodal and multimodal maximum annual flood density functions were discovered. In order to determine generating mechanisms, a monthly partitioning of the annual maximum floods was undertaken. The timing of the floods revealed that the unimodal distributions reflected a single flood generating mechanism while the multi-modal densities reflected two or more mechanisms. Based on the division of the flood series by mechanisms, nine homogeneous regions were delineated. L-moment distributional homogeneity tests along with smaller standard errors for the regional equations supported the delineation.  相似文献   
799.
生态旅游作为“保护生态”和“发展经济”双赢理念的新兴旅游类型,被西部各省(区、市)所关注并将其定为本地区发展的主导产业.通过对西部地区的生态旅游资源优缺点、市场定位、产品转化及空间布局的分析,初步勾画了西部生态旅游业的发展前景,并提出相应地发展策略.  相似文献   
800.
Summary The balance of evidence suggests a perceptible human influence on global ecosystems. Human activities are affecting the global ecosystem, some directly and some indirectly. If researchers could clarify the extent to which specific human activities affect global ecosystems, they would be in a much better position to suggest strategies for mitigating against the worst disturbances. Sophisticated statistical analysis can help in interpreting the influence of specific human activities on global ecosystems more carefully. This study aims at identifying significant or influential human activities (i.e. factors) on CO2 emissions using statistical analyses. The study was conducted for two cases: (i) developed countries and (ii) developing countries. In developed countries, this study identified three influential human activities for CO2 emissions: (i) combustion of fossil fuels, (ii) population pressure on natural and terrestrial ecosystems, and (iii) land use change. In developing countries, the significant human activities causing an upsurge of CO2 emissions are: (i) combustion of fossil fuels, (ii) terrestrial ecosystem strength and (iii) land use change. Among these factors, combustion of fossil fuels is the most influential human activity for CO2 emissions both in developed and developing countries. Regression analysis based on the factor scores indicated that combustion of fossil fuels has significant positive influence on CO2 emissions in both developed and developing countries. Terrestrial ecosystem strength has a significant negative influence on CO2 emissions. Land use change and CO2 emissions are positively related, although regression analysis showed that the influence of land use change on CO2 emissions was still insignificant. It is anticipated, from the findings of this study, that CO2 emissions can be reduced by reducing fossil-fuel consumption and switching to alternative energy sources, preserving exiting forests, planting trees on abandoned and degraded forest lands, or by planting trees by social/agroforestry on agricultural lands.  相似文献   
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