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1.
Shu-Yii Wu Yong-Fang Liu Ya-Chieh Li Chun-Min Liu 《International Journal of Green Energy》2015,12(10):1025-1030
The CO2 absorption capacities of potassium glycinate, potassium sarcosinate (choline, proline), mono-ethanolamine (MEA), and tri-ethanolamine were evaluated to find the optimal absorbent for separating CO2 from gaseous products by a CO2 purification process. The absorption loading, desorption efficiency, cost, and environmental tolerance were assessed to select the optimal absorbent. MEA was found to be the optimum absorbent for separating the CO2 and H2 mixture in gaseous product. The maximum absorption loading rate was 0.77 mol CO2 per mol MEA at temperature of 20°C and absorbent concentration of 2.5 mol/L, whereas desorption efficiency was 90% by heating for 3 h at 130°C. MEA was found to be an optimal absorbent for the purification process of CO2 during gaseous production. 相似文献
2.
Kuang-Lung Fan 《Chemistry and Ecology》1992,6(1):213-224
The increasing use of sea water for industrial cooling presents a real threat to the ecological environment in the ocean. in Taiwan where many electric power plants along the coast take sea water for cooling, people are concerned seriously about nuclear power plants. There are three nuclear power plants in Taiwan. Each plant has two units for generating power. the first two are located along the northern coast of Taiwan. the third is located in Kenting National Park along the coast of southernmost Taiwan. the plants take sea water for cooling, and discharge their heated effluents to the ocean surface from the coast. the thermal effluents have variable effects on the ecological environment near the plants. Fishermen living near the power plants complain that the heated water affects the inshore fishery catch. in addition, the thermal water from the second plant is easily accumulated near the coastal zone to influence the nearby swimming area in the summer-time. the thermal water from the third plant bleaches or kills some corals in shallow water near the outlet, and this conflicts with the interests of Kenting National Park. 相似文献
3.
修文群 《中国人口.资源与环境》2005,15(2):122-126
面对当前我国经济开发区发展所面临的主要挑战,无论从自身经济增长规律出发.还是应对外部竞争压力,在新形势下,信息化是实现开发区产业升级与可持续发展的必由之路。如何针对开发区实际状况,系统、科学地进行信息化建设,包括大力发展信息产业并使其成为支柱产业,开创新经济增长点;以信息技术改造传统产业,促进产业升级与结构调整;以电子政务提高政府管理水平与服务效率、以电子商务提高企业的经营绩效与创新能力;以信息化推动城市化进程,提高人口素质与生活水平等。针对上述议题,特提出以“数字城市”建设、完善信息产业链为核心的开发区信息化发展战略。 相似文献
4.
Evolution of environmental impact assessment as applied to watershed modification projects in Canada
Herman J. Dirschl Nicholas S. Novakowski M. Husain Sadar 《Environmental management》1993,17(4):545-555
This article reviews the application of environmental impact assessment (EIA) procedures and practices to three watershed
modification projects situaled in western Canada. These ventures were justified for accelerating regional economic development,
and cover the period during which public concerns for protecting the environment rapidly made their way into the national
political agenda. An historical account and analysis of the situation, therefore, seems desirable in order to understand the
development of EIA processes, practices, and methodologies since the start of construction of the first project in 1961. This
study concludes that there has been good progress in predicting and evaluating environmental and related social impacts of
watershed modification proposals. However, a number of obstacles need to be overcome before EIA can firmly establish itself
as an effective planning tool. These difficulties include jurisdictional confusions and conflicts, division of authority and
responsibility in designing and implementing appropriate mitigative and monitoring measures, lack of tested EIA methodologies,
and limited availability of qualified human resources. A number of conclusions and suggestions are offered so that future
watershed modification proposals may be planned and implemented in a more environmentally sustainable fashion. These include:
(1) EIA processes must be completed before irrevocable decisions are made. (2) Any major intrusion into a watershed is likely
to impact on some major components of the ecosystem(s). (3) Mitigation costs must form part of the benefit-cost analysis of
any project proposal. (4) Interjurisdictional cooperation is imperative where watersheds cross political boundaries. (5) The
EIA process is a public process, hence public concerns must be dealt with fairly. (6) The role of science in the EIA process
must be at arms length from project proponents and regulators, and allowed to function in the interest of the protection of
the environment and public health and safety.
The views expressed here are the authors’ own and do not necessarily reflect those of FEARO and/or other government agencies
and officials involved in the review of these projects. 相似文献
5.
论环境产业 总被引:1,自引:0,他引:1
曹曼 《中国人口.资源与环境》2008,18(6)
本文在可持续发展视角下,把环境的保护、修复、维护的生产活动及与之直接相关的服务活动称为环境产韭,包括发挥减少、避免污染环境作用的资源再利用鼗和发挥治理污染物与修复、改善环境作用的环境维护业.通过探讨环境产业的内涵、发展历程、运行机制和在产业体系中的位置与作用,指出环境产业是在法规保障下政府强行推动产生和发展起来的,是产业体系中不可缺少的重要组成部分;考虑自然环境对社会行为的影响,改进政府行为构建适台环境产业与传统产业协调发展的经济体制是加快发展环境产业的关键. 相似文献
6.
Studies on paleosols under an archaeological landmark of a rare type (a complex of kurgans with “whiskers”) dating from the Early Iron Age (the fourth century AD) have been performed in the steppe zone of the Transural Plateau. The size and shape of third-order soil polygons under stony ridges (“whiskers”) between the kurgans have been described in detail. The results have shown that the paleosol under the kurgans erected at the turn of the Late Sarmatian and Hun times (1600 years ago) is characterized by a higher humus content and deeper location of the carbonate horizon, compared to the recent soil. This indicates that an increase in atmospheric humidity took place in the fourth century AD. 相似文献
7.
P.P. Povinec H. Bokuniewicz W.C. Burnett J. Cable M. Charette J.-F. Comanducci E.A. Kontar W.S. Moore J.A. Oberdorfer J. de Oliveira R. Peterson T. Stieglitz M. Taniguchi 《Journal of environmental radioactivity》2008,99(10):1596
Results of groundwater and seawater analyses for radioactive (3H, 222Rn, 223Ra, 224Ra, 226Ra, and 228Ra) and stable (D and 18O) isotopes are presented together with in situ spatial mapping and time series 222Rn measurements in seawater, direct seepage measurements using manual and automated seepage meters, pore water investigations using different tracers and piezometric techniques, and geoelectric surveys probing the coast. This study represents first time that such a new complex arsenal of radioactive and non-radioactive tracer techniques and geophysical methods have been used for simultaneous submarine groundwater discharge (SGD) investigations. Large fluctuations of SGD fluxes were observed at sites situated only a few meters apart (from 0 cm d−1 to 360 cm d−1; the unit represents cm3/cm2/day), as well as during a few hours (from 0 cm d−1 to 110 cm d−1), strongly depending on the tidal fluctuations. The average SGD flux estimated from continuous 222Rn measurements is 17 ± 10 cm d−1. Integrated coastal SGD flux estimated for the Ubatuba coast using radium isotopes is about 7 × 103 m3 d−1 per km of the coast. The isotopic composition (δD and δ18O) of submarine waters was characterised by significant variability and heavy isotope enrichment, indicating that the contribution of groundwater in submarine waters varied from a small percentage to 20%. However, this contribution with increasing offshore distance became negligible. Automated seepage meters and time series measurements of 222Rn activity concentration showed a negative correlation between the SGD rates and tidal stage. This is likely caused by sea level changes as tidal effects induce variations of hydraulic gradients. The geoelectric probing and piezometric measurements contributed to better understanding of the spatial distribution of different water masses present along the coast. The radium isotope data showed scattered distributions with offshore distance, which imply that seawater in a complex coast with many small bays and islands was influenced by local currents and groundwater/seawater mixing. This has also been confirmed by a relatively short residence time of 1–2 weeks for water within 25 km offshore, as obtained by short-lived radium isotopes. The irregular distribution of SGD seen at Ubatuba is a characteristic of fractured rock aquifers, fed by coastal groundwater and recirculated seawater with small admixtures of groundwater, which is of potential environmental concern and has implications on the management of freshwater resources in the region. 相似文献
8.
Garey A. Fox George J. Sabbagh Robert W. Malone Ken Rojas 《Journal of the American Water Resources Association》2007,43(6):1359-1372
Abstract: Few studies exist that evaluate or apply pesticide transport models based on measured parent and metabolite concentrations in fields with subsurface drainage. Furthermore, recent research suggests pesticide transport through exceedingly efficient direct connections, which occur when macropores are hydrologically connected to subsurface drains, but this connectivity has been simulated at only one field site in Allen County, Indiana. This research evaluates the Root Zone Water Quality Model (RZWQM) in simulating the transport of a parent compound and its metabolite at two subsurface drained field sites. Previous research used one of the field sites to test the original modification of the RZWQM to simulate directly connected macropores for bromide and the parent compound, but not for the metabolite. This research will evaluate RZWQM for parent/metabolite transformation and transport at this first field site, along with evaluating the model at an additional field site to evaluate whether the parameters for direct connectivity are transferable and whether model performance is consistent for the two field sites with unique soil, hydrologic, and environmental conditions. Isoxaflutole, the active ingredient in BALANCE® herbicide, was applied to both fields. Isoxaflutole rapidly degrades into a metabolite (RPA 202248). This research used calibrated RZWQM models for each field based on observed subsurface drain flow and/or edge of field conservative tracer concentrations in subsurface flow. The calibrated models for both field sites required a portion (approximately 2% but this fraction may require calibration) of the available water and chemical in macropore flow to be routed directly into the subsurface drains to simulate peak concentrations in edge of field subsurface drain flow shortly after chemical applications. Confirming the results from the first field site, the existing modification for directly connected macropores continually failed to predict pesticide concentrations on the recession limbs of drainage hydrographs, suggesting that the current strategy only partially accounts for direct connectivity. Thirty‐year distributions of annual mass (drainage) loss of parent and metabolite in terms of percent of isoxaflutole applied suggested annual simulated percent losses of parent and metabolite (3.04 and 1.31%) no greater in drainage than losses in runoff on nondrained fields as reported in the literature. 相似文献
9.
爆炸事故过程分析中不确定性问题处理方法 总被引:1,自引:0,他引:1
针对事故过程分析中的不确定性问题,指出了不确定问题在危险分析中的重要性及处理该问题的复杂性和难点,列出了几种基于非线性数学方法处理不确定问题的基本方法,如微分法、MonteCarlo模拟、Fourier方法、响应表面法等,并对之进行了比较.建议在处理事故过程的不确定性时采用Monte Carlo模拟. 相似文献
10.
焦化废水处理过程中产生的焦油、污泥和结晶杂盐等固相物质,既有资源属性,又有污染特性,但目前缺乏基于能源、经济及环境影响方面的评估.本研究阐述了3类固相物质的形成机制,建立了质量当量计算及处置方法评价模型.以宝武集团韶关钢铁股份有限公司焦化厂(二期)焦化废水处理工程的A/O/H/O(厌氧/好氧/水解/好氧)流化床工艺作为考察对象,利用工程运行参数和水质统计数据进行固相物质的产量推算,结果发现,焦油、物化污泥、生物污泥(含水率为80%)和工业杂盐的产率分别为0.186、5.80、4.24和1.97 kg·m-3.通过处置方法评价模型明确了焦油焚烧、污泥热解、结晶杂盐分盐提纯后工业应用是最佳处置方案,在60 m3·h-1废水处理规模的固相物质处置过程中,每年约产生1177 MWh的能源,获得135.0万元的经济效益,排放627.0 t CO2,表明能源回收、经济效益和环境影响的协同存在. 相似文献