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Journal of Material Cycles and Waste Management - Owing to various advantages of artificial marble compared to natural marble, its application has been rising exponentially, which has resulted in...  相似文献   
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碱性过硫酸钾消解紫外分光光度法测定水中总氮采用的消解器皿是玻璃比色管,易造成空白偏高、结果偏低等问题。采用双圆柱状的消解杯对水样进行消解。结果表明,消解杯消解水中总氮,线性相关系数均大于0.999,检出限为0.05 mg/L,相对标准偏差小于5%,相对误差为0.88%~1.00%;改进后的消解器皿具有较好的精密度和准确度,能够更加准确测定水中总氮的含量。  相似文献   
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The Jain tradition of ecological awareness and sustainability has been well documented over the last 25 years, although its roots lie deep in Indian history, specifically in texts such as the Tattvārtha Sūtra and ācārā?ga Sūtra. This traditional body of knowledge includes a long-standing theory and practice of personal, social and environmental sustainability, addressing such views as the interconnectedness of humans and the laws of nature, the interdependence of everything in the universe, the responsibility of humans to conserve and preserve natural resources, the avoidance of wanton and unnecessary waste generation, and a general aversion to mistreating or abusing the environment. These views encapsulate the lifestyles of some ten million people, including both mendicants and laity. Similarly, Maharishi Vedic Science, the systematic exploration and practical application of the Veda and Vedic Literature as taught by Maharishi Mahesh Yogi, makes a compelling case for establishing the unity of human life with nature and for promoting actions which guarantee both the protection of nature and protection by it. The purpose of this paper is to examine the relationship between the principles of sustainability in Jainism and the corresponding viewpoint of Maharishi Vedic Science, including supporting scientific evidence of its application, and to posit their contribution to a sustainable world future.  相似文献   
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In the present study, the distribution patterns of various metals were analyzed and compared using PM samples collected concurrently from three monitoring sites located in Korea (Seoul, Busan, and Jeju island) in December 2002. As these sites can represent metal pollution with different degrees of anthropogenic activities, their concentration levels were distinguished in a systematic manner in the order of Jeju, Busan, and Seoul. By comparing the present data sets with those measured previously from other locations in Korea and around the world, we attempted to diagnose the general status of elemental pollution on the Korean peninsula. Through an application of different statistical approaches, the major processes controlling elemental levels were assessed for each of the three study sites. The results indicated the importance of both crustal and anthropogenic sources in all sites with their relative roles varying significantly from each other. The results of the metal analysis data, when examined in relation to back trajectory analysis, confirmed that their concentration changes are affected quite sensitively with air mass movement patterns. The overall results of this study consistently indicated the contribution of a strong anthropogenic source area (e.g., China) to the observed metal concentration levels in the study area, but the strengths of such signals vary considerably across the Korean peninsula.  相似文献   
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Kim Y  Tanaka K  Lee YW  Chung J 《Chemosphere》2008,70(6):990-1001
An up-flow biological anoxic filter (BANF) has been developed to achieve high removal performance of suspended solids and BOD removal as well as nitrogen. With a view to understand treatment mechanisms, we developed a filtration model that incorporates filtration, deposit scoring and biological reactions simultaneously. The biological reactions consist of four types of reaction; dissolution of organic particles; utilization of dissolved organic matter; denitrification; and self-degradation of bacteria. Whereas the reactor is generally assumed to be a plug flow reactor in the filtration model, it is assumed a continuous-flow stirred tank reactor (CSTR) in the model of biological reactions. The hydrodynamics is supposed that the filter bottom (the portion sludge settled) is a CSTR and the filter bed (the portion filled with filter media) consists of number of CSTR of equal size arranged in series. The model obtained in this study was verified and simulated using experimental results taken from a pilot-scale plant and predicted the experimental data well, applying to design and operate BANF.  相似文献   
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