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111.
Effects of repeated pollutant exposure on growth, locomotor performance, and behavior have rarely been evaluated in reptiles. We administered three doses of malathion (2.0, 20, or 100mg/kg body weight) to western fence lizards (Sceloporus occidentalis) over an 81day period. Eight and 23% mortality occurred at 20 and 100mg/kg (p=0.079) and 85% of lizards in the 100mg/kg group exhibited clinical symptoms of poisoning. Growth, food consumption, body condition index, and terrestrial locomotor performance were not significantly influenced by malathion. However, arboreal sprint velocity was significantly reduced in lizards receiving 100mg/kg. Fifty percent of lizards in the 100mg/kg group also refused to sprint in the arboreal setting (p=0.085). Based on these results, arboreal locomotor performance was the most sensitive metric of exposure we evaluated. Further study of compounds such as malathion is warranted due to highly variable application rates and exposure scenarios. 相似文献
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Thomas Zobel 《Journal of Environmental Planning and Management》2016,59(4):587-606
The debate concerning the environmental effectiveness of environmental management systems (EMS) based on ISO 14001 is still open and scholars have called for further studies that can explain the contrasting evidence in previous research. As a response, this study aims to contribute knowledge about the effects of ISO 14001-based EMS by presenting fact-based environmental data. The study focuses on changes in performance over a period of 12 years and includes both firms with an EMS (66 firms) and firms without one (50 firms). Consideration is given to the improvement efforts in the firms before EMS adoption making it possible to neutralize any selection effects where better environmental performance precedes ISO 14001 adoption. Analysis has been carried out using statistical methods for six different environmental areas. No statistically significant differences between certified and non-certified firms concerning the change in the rate of improvement could be found in any of the six areas. However, it can be suspected that EMS adoption has positive effects on energy use and waste production whereas the non-adopting firms seem to perform better concerning air emissions. These mixed results mirrors previous research, which is rather worrying considering the worldwide popularity of EMS based on ISO 14001 in industry. 相似文献
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Energy service is an effective way to promote energy conservation by market mechanisms, including energy saving services, energy procurement, supply of many varieties of energy, supply of renewable energy technologies, energy-related consulting services, risk management, etc. China is a major energy consumer but energy is in short supply, and the efficiency of energy use is low. China’s energy service industry has expanded rapidly, in terms of both the number of new Energy Service Companies entering the market and amount of capital invested in Energy Performance Contracting projects, but the energy service sector in China is still at an early stage of development. Developed countries began early in developing the energy service sector and their energy service market is mature, and the experience of developed countries shows that energy services play a significant role in advancing energy saving and emission reduction. Under the new situation, China needs combine energy services experience of developed countries, and take following measures to accelerate China’s energy services rapid and healthy development, including the long-term aspects of policy planning, energy-saving core technology, finance and capital investment, public sector reductions, personnel training, and so on. 相似文献
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为探讨Cu2+、p H和流速对固定化斜生栅藻去除畜禽废水中NH+4-N、TP效果的影响,在实验室条件下模拟实际污水处理过程,并采用正交实验方案对结果进行分析。结果表明低质量浓度Cu2+(0~0.05 mg/L)改善藻的净化效果,高质量浓度Cu2+(0.50~5.00 mg/L)抑制藻的净化效果;在p H较高的条件下(p H=9),固定化斜生栅藻的净化效果明显提高;流速对结果没有明显影响。通过正交实验,得出固定化斜生栅藻去除畜禽废水中NH+4-N、TP的优化条件如下:Cu2+质量浓度为0.05 mg/L,p H为9,流速为0.3 m/s。此时NH+4-N去除率为96.11%,TP去除率为97.53%。 相似文献
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为了对比径向外喷和轴向喷雾下的低阻文丘里振弦栅耦合除尘效果,以除尘效率和系统阻力为参照,选定喉管气速、振弦栅数、纤维丝间隙和喉管液气比进行单因素实验。结果表明2种喷雾方式的除尘效率和系统阻力的变化趋势相同。利用SPSS软件进行4因素3水平正交实验设计,在特定参数条件下,2种喷雾方式的因素影响排序相同,除尘效率为纤维栅数>纤维丝间隙>喉管气速>喷雾量;系统阻力为喉管气速>纤维栅数>纤维丝间隙>喷雾量;径向外喷最佳配置为喉管气速24 m/s、喷雾量2.3 L/min、2块间隙为0.8 mm纤维栅板;轴向喷雾为喉管气速28 m/s、喷雾量2.4 L/min、2块间隙为0.8 mm纤维栅板;在最优配置下的除尘性能为径向外喷>轴向喷雾。 相似文献
120.
Ravikumar KVG Debayan Ghosh Mrudula Pulimi Chandrasekaran Natarajan Amitava Mukherjee 《Frontiers of Environmental Science & Engineering》2020,14(1):16