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231.
Yin Zhou Dong Xu Enrong Xiao Dan Xu Peng Xu Xia Zhang Qiaohong Zhou Feng He Zhenbin Wu 《环境科学学报(英文版)》2018,30(8):54-62
To find suitable wetland plants for constructed wetland-microbial fuel cells(CW-MFCs),four commonly used wetland plants, including Canna indica, Cyperus alternifolius L., Acorus calamus, and Arundo donax, were investigated for their electrogenic performance and physiological changes during non-growing seasons. The maximum power output of12.82 mW/m~2 was achieved in the A. donax CW-MFC only when root exudates were being released. The results also showed that use of an additional carbon source could remarkably improve the performance of electricity generation in the C. indica and A. donax CW-MFCs at relatively low temperatures(2–15°C). However, A. calamus withered before the end of the experiment, whereas the other three plants survived the winter safely, although their relative growth rate values and the maximum quantum yield of PSII(Fv/Fm) significantly declined, and free proline and malondialdehyde significantly accumulated in their leaves.On the basis of correlation analysis, temperature had a greater effect on plant physiology than voltage. The results offer a valuable reference for plant selection for CW-MFCs. 相似文献
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234.
Electromagnetic field sources used for communication always have been subject of serious interest. There are many publications
concerning exposure and risk assessment of the working in such environment. Results of epidemiological study performed in
Bulgaria in the 1990's show exceeding of the maximal permissible values especially in radio stations for the personnel in
24 h working shift [Israel et al. (1992). Study of the electromagnetic in its influence on personnel working in radio and
TV stations, Report, National Centre of Hygiene, Medical Ecology and Nutrition; Israel and Tomov (2001). Epidemiological study
of the effects of radiofrequency radiation on operators in radio, TV and relay stations, Proceeding of the Eastern European
Regional Meeting and Workshop “Measurements and Criteria for Standard Harmonization in the field of EMF Exposure” and WHO
EMF Standards Harmonization Meeting, Varna, Bulgaria, 28 April—3 May, 2001, pp.145–153]. In the last years the situation is
strongly influenced by the development of the technology which leads to changes in equipment in radio and TV stations, using
lower power, facilitate the working regime. The paper presents data of exposure assessment of different professional groups
in selected radio and TV stations. Assessment is being performed on basis of EMF parameters values and energetic load calculations
according to the national legislation. Data are compared with the results of previous investigation to evaluate the new situation
in this branch. Exposure levels are much lower than those in the previous study, and lower compared to the exposure limits,
as well [Israel et al. (1992). Study of the electromagnetic in its influence on personnel working in radio and TV stations,
Report, National Centre of Hygiene, Medical Ecology and Nutrition; Israel and Tomov (2001). Epidemiological study of the effects
of radiofrequency radiation on operators in radio, TV and relay stations, Proceeding of the Eastern European Regional Meeting
and␣Workshop “Measurements and Criteria for Standard Harmonization in the field of EMF Exposure” and WHO EMF Standards Harmonization
Meeting, Varna, Bulgaria, 28 April—3 May, 2001, pp.145–153]. 相似文献
235.
本文列举了影响户外柜式通信电源系统的各种自然环境因素,并讨论了各个因素对产品的主要影响机理,提出了产品设计时需要考虑的要点。为该类产品的耐环境设计和可靠性设计提供了必要的参考信息,对其它户外电子设备的设计也有借鉴意义。 相似文献
236.
237.
《Process Safety and Environmental Protection》2014,92(5):447-455
Today, the world's energy needs are still supplied mainly from fossil fuel based resources. This is true for electricity generation as well, thus making the power sector responsible for 45% of greenhouse gas emissions. The present climate crisis has made it necessary to minimise emissions in power generation, with low-carbon energy sources taking on greater significance in recent years. However, most low-carbon sources have inherent problems, like intermittency and high capital expenditure. A suitable alternative is carbon capture and storage (CCS) technology which allows continued fossil fuel-based electricity generation at much lower rates of emission. Two approaches are possible in the deployment of CCS technology. The first is to introduce new power plants equipped for carbon dioxide (CO2) capture, while systematically shutting down existing coal power plants. Another is to retrofit existing power plants for CO2 capture. These approaches are compared in this work. The study shows that allowing CCS retrofitting of existing power plants can reduce the overall cost requirement significantly. In addition, a sensitivity analysis is also done to study the effect of nuclear energy on the overall energy mix. 相似文献
238.
油气回收技术在加油站中的应用 总被引:9,自引:0,他引:9
介绍了加油站油气回收的意义、油气回收系统的工艺原理及油气回收系统性能的检测方法.对油气回收系统设备的安装进行了说明,并对油气回收的综合利用提出了建议。 相似文献
239.
Vultures, the only vertebrate obligate scavengers, are currently facing a dramatic worldwide decline with over half of vulture species now classified as threatened. To address this widespread decline, the use of feeding stations has been widely advocated in recovery programs. However, providing food that is more predictable in time and space than natural resources could disrupt the ecological scavenging service provided by vultures. In this study, we build a multi-agent system (MAS), which describes the social foraging behavior of Gyps vultures in order to investigate how resource predictability in space and resource management affect scavenging service efficiency. We study the possibility that vultures take into account feeding station location in addition of using local enhancement. Our results show that the efficiency of the scavenging service is heavily affected by the way resources are distributed between feeding stations and natural areas. Nevertheless, it appears possible to minimize a loss in service efficiency by increasing the number of feeding stations while keeping the total amount of resources available constant, thus reducing the predictability of the resources located on the stations. We illustrate our work in the case of European feeding stations that provide supplementary resources in areas where natural ones are scarce. Moreover, we discuss the implications worldwide, in particular in the case of India, where feeding stations for vultures are intended to lure individuals away from potentially harmful natural carrion. 相似文献
240.
We present a method for detecting the zones where an irregularly sampled variable changes abruptly in the plane. Such zones
are called Zones of Abrupt Change (ZACs). This method not only allows estimation of ZACs, but also testing of their statistical
significance against the null hypothesis of a stationary correlated random field. The sampling pattern, in particular its
local density, is crucial in the detection of potential ZACs. In this paper, we address the problem of evaluating the sampling
pattern by assessing the power of the local test used for detecting ZACs. It is shown that mapping the power allows us to
identify zones where ZACs may or may not be detected. The methodology is applied to a soil data set sampled at eight different
dates in an agricultural field. Detecting ZACs for the soil water content allowed us to identify permanent structures in the
agricultural field related to the boundaries between different soil types. Mapping the power for various sampling densities
proved to be useful to determine the minimal sampling density necessary for detecting ZACs.
相似文献
Edith GabrielEmail: |