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Seasonal dynamics of gas regulation service in forest ecosystem 被引量:2
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作者 李士美 谢高地 +2 位作者 于贵瑞 张彩霞 盖力强 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期99-103,I0004,共6页
Using the 3-year observational data from ChinaFlux (Chinese Terrestrial Ecosystem Flux Research Network), we studied the gas regulation flux dynamics and cumulative process of gas regulation value in Qianyanzhou mid... Using the 3-year observational data from ChinaFlux (Chinese Terrestrial Ecosystem Flux Research Network), we studied the gas regulation flux dynamics and cumulative process of gas regulation value in Qianyanzhou middle subtropical plantation (QYF) and Changbai Mountain temperate mixed forest (CBF). The gas regulation service was differentiated into vegetation gas regulation service and net ecosystem gas regulation service. Carbon tax approach, reforestation cost approach and industrial oxygen approach were employed to calculate gas regulation value. Results show that there was significant seasonal variation in vegetation gas regulation flux. Daily CO2 uptake fluxes averaged 82.00 kg·ha^-·d^-1 and 59.37 kg·ha^-·d^-1 and the corresponding 02 emission fluxes were 59.65 kg·ha^-·d^-1 and 43.19 kg·ha^-·d^-1 for QYF and CBF, respectively. The cumulative curves of vegetation gas regulation value always followed a sigmoid shape, and the annual gas regulation value produced by vegetation was RMB 14342.69 yuan·ha^-1 and RMB 10384.18 yuan·ha^-1 for both QYF and CBF, respectively. In terms of monthly net ecosystem gas regulation service, QYF appeared as a CO2 sink and O2 source for the whole year, while CBF appeared to be a CO2 sink and O2 source mainly in the period between May and September. The cumulative curves of net ecosystem gas regulation value presented a sigmoid ("S") shape for QYF, while a unimodal type curve for CBF. The annual net ecosystem gas regulation value was 8470.52 yuan·ha^-1 and 5091.98yuan·ha^-1 for QYF and CBF, respectively. The economic value of both the vegetation gas regulation service and net ecosystem gas regulation service were mainly produced between May and October. 展开更多
关键词 gas regulation service flux CUMULATIVE CO2 uptake O2 emission
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Economic valuation of gas regulation as a service by rice-duck-fish complex ecosystem 被引量:10
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作者 Yuan Welling Cao Cougui Wang Jinping 《Ecological Economy》 2008年第3期266-272,共7页
Valuating the fimction of ecosystem services is crucial for accounting green GDP, making a conservation policy of ecological environment and the decision of regional development as well as sustainable development stra... Valuating the fimction of ecosystem services is crucial for accounting green GDP, making a conservation policy of ecological environment and the decision of regional development as well as sustainable development strategy. R ice-duck-fish symbiosis has been promoted in several developing countries as a way of increasing incomes for rice farmers, but investigations of its value have mainly focused on direct economic' benefits, such as food and raw material production. Few studies have been conducted on the estimation of indirect services provided by rice-duck-fish complex ecosystem. The gas regulation service and its economic values provided by rice-duck-fish complex ecosystem were studied in Wuhan, China. The major components of gas regulation are O2 emission and greenhouse gases (GHGs, CO2) regulation. The results show that O2 emission from different treatments (including rice-duck (RD), rice-fish (RF), rice-duck-fish (RDF) and rice (CK)) ranged from 26,370 kg/ha to 33,910 kg/ha per year. with an economic value of 10,050-12,920 yuan/ha per ),ear (Chinese currency: 1 euro =10.2475 yuan, August 28, 2007). The net GHGs exchange varied from 1,200 to 3,320 kg/ha per year; and its economic value ranged from 1,040 yuan/ha to 2,900 yuan/ha per year Consequently, the total economic value of gas regulation provided by symbiosis complex ecosystems ranged from 11,090 yuan/ha to 15,820 yuan/ha per year. and the maximum overall economic value of gas regulation was provided by RDF complex ecosystem. The work will be useful for further understanding of the functions of rice-duck-fish complex ecos.vstem services and supplying the theoretical references to agricultural policy. 展开更多
关键词 Eeosystem services gas regulation GHGs emission: O2 emission Riee-duek-fish complex ecosystems
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Regulations and Practice on Flue Gas Denitrification for Coal-Fired Power Plants in China
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作者 Zhu Fahua1 and Zhao Guohua2 1. State Power Environmental Protection Research Institute 2. Nanjing University of Information Science & Technology 《Electricity》 2008年第1期49-52,共4页
In China, according to the relative up-to-date regulations and standards, the maincontrol measure for NOX emission of coal-fired power plants is, in principle, low NOXcombustion. However, in recent years, more and mor... In China, according to the relative up-to-date regulations and standards, the maincontrol measure for NOX emission of coal-fired power plants is, in principle, low NOXcombustion. However, in recent years, more and more newlyapproved coal-fired plantswere required to install flue gas denitrification equipment. This article expounds if fluegas denitrification is necessary from several aspects, including constitution of NOX, itsimpact to environment, operation ofdeNOXequipment in USA, as wellas the differencein ambient air quality standard between China and World Health Organization. It setsforth themes in urgent need of study and areas where deNOX equipment is necessaryfor new projects, besides a recommendation that the emission standards for thermalpowerplants should be revised as soon as possible in China. 展开更多
关键词 regulations and Practice on Flue gas Denitrification for Coal-Fired Power Plants in China
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Physiological responses and adjustment mechanisms of the dominate species of natural vegetation of Eastern Tengger Desert 被引量:1
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作者 HaiYan Zhou HuiJuan Tan +3 位作者 ZhiShan Zhang XiaoHong Jia HengWen Fan JianLi Yuan 《Research in Cold and Arid Regions》 2010年第5期455-463,共9页
Reaumuria soongorica and Salsola passerina have significant differences in ecophysiological characteristics, which change with the environmental variations. Although they live together for a long period of time, their... Reaumuria soongorica and Salsola passerina have significant differences in ecophysiological characteristics, which change with the environmental variations. Although they live together for a long period of time, their adaptive mechanisms to environmental stresses are very different. As two extreme xerophytes, Reaumuria soongorica and Salsola passerina differ significantly from other psammophytes in ecophysiological characteristics; they can survive in lower water potential, and can even grow in piedmont areas. Low water potential may be related to the existence of osmosis-regulating substance, such as praline, which can strengthen the capacity of water absorption. Compared to other psammophytes, Reaumuria soongorica and Salsola passerina have a higher degree of photo-inhibition under the same condition, and the photo-inhibition can lead to destruction of the photosynthetic pigment, nevertheless, this photo-inhibition can be repaired under suitable conditions in the morning and evening. 展开更多
关键词 gas exchange water potential osmosis regulating Reaumuria soongorica Salsola passerina
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Using the EMD Method to Determine Fault Criterion for Medium-low Pressure Gas Regulators 被引量:11
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作者 HAO Xuejun LIU Qiang +1 位作者 YANG Guobin DU Yi 《Journal of Thermal Science》 SCIE EI CAS CSCD 2015年第6期557-561,共5页
By extracting the outlet pressure data of gas regulators,this paper uses the EMD toolbox of the MATLAB software,which can perform data decomposition and the Hilbert-Huang Transform to find the rules with fault data.Ev... By extracting the outlet pressure data of gas regulators,this paper uses the EMD toolbox of the MATLAB software,which can perform data decomposition and the Hilbert-Huang Transform to find the rules with fault data.Eventually,the medium-low pressure gas regulator fault criterion can be established. 展开更多
关键词 medium-low pressure gas regulator EMD decomposition fault criterion
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Research on Online Safety Precaution Technology of a High-medium Pressure Gas Regulator 被引量:2
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作者 HAO Xuejun LIU Xuhai +1 位作者 LI Xiaxi ZHAO Xin 《Journal of Thermal Science》 SCIE EI CAS CSCD 2017年第3期229-234,共6页
In view of some of the characteristics of a high-medium pressure gas regulator, such as small fault samples, many fault types and complex fault features etc, in order to improve the accuracy of fault precaution in thi... In view of some of the characteristics of a high-medium pressure gas regulator, such as small fault samples, many fault types and complex fault features etc, in order to improve the accuracy of fault precaution in this paper, a fault diagnosis method based on the combination of the improved wavelet packet and pressure harmonic distortion rate is proposed. On the basis of the harmonic distortion rate of the outlet pressure and the energy value of each frequency band obtained by improved wavelet packet decomposition, the rules for fault data were summarized. Finally, a safety precaution model of the high-medium pressure gas regulator is established. 展开更多
关键词 high-medium pressure gas regulator improved wavelet packet harmonic distortion rate safety precaution model
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Evaluation of Ecosystem Services Provided by 10 Typical Rice Paddies in China 被引量:8
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作者 肖玉 安凯 +1 位作者 谢高地 鲁春霞 《Journal of Resources and Ecology》 CSCD 2011年第4期328-337,共10页
Based on reference review, this study investigated ecosystem services supported by 10 typical rice paddies in six rice planting regions of China. The services were primary production, gas regulation, nitrogen transfor... Based on reference review, this study investigated ecosystem services supported by 10 typical rice paddies in six rice planting regions of China. The services were primary production, gas regulation, nitrogen transformation, soil organic matter accumulation, and water regulation and flood control. The results indicated that grain production of the 10 rice paddies was between 4.71 and 12.18 t ha^-1 y^-1; straw production was 4.65 to 9.79 t ha^-1 y^-1; gas regulation was calculated to emit O2 ranging from 8.27 to 19.69 t ha^-1 y^-1 and to assimilate greenhouse gases ranging from -2.13 to 19.24 t ha^-1 y^-1 (in CO2 equivalent); nitrogen transformation was estimated as nitrogen input ranging from 209.70 to 513.93 kg N ha^-1 y^-1 and nitrogen output of 112.87 to 332.69 kg N ha^-1 y^-1; soil organic matter accumulation was calculated to be between 0.69 and 4.88 t C ha^-1 y^-1; water regulation was estimated to consume water resources of 19875 m3 ha^-1 y^-1 and to support water resources of 6430 m3 ha^-1 y^-1; and flood control of several of the rice paddies was calculated to be 1500 m3 ha^-1 y^-1. The integrated economic value of ecosystem services of these rice paddies was estimated at USD 8605–21 405 ha^-1 y^-1, of which 74%–89% of the value can be ascribed to ecosystem services outside primary production. The results also indicated that the integrated economic value of the ecosystem services of the 10 rice paddies was higher when nitrogen fertilizer was applied in the range of 275 to 297 kg N ha^-1. Until now, the economic value of the rice paddy ecosystem has been underestimated as only the economic value of grain and straw production was previously calculated. As more and more forest land and grassland is lost to urban and industrial use, cropland and especially rice paddies, will become more ecologically important to society. The economic value of ecosystem services supplied by rice paddies, outside primary production, are worthy of increased research attention. 展开更多
关键词 rice paddy ecosystem services gas regulation soil organic matter accumulation nitrogen transformation
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Dynamic modeling and simulation of a pressurized system used in flight vehicle 被引量:4
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作者 Bing SUN Qi XU Yang CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第6期1232-1248,共17页
For a typical pressurized system with a novel dual-stage gas pressure reducing regulator,a system model is established with modular models of various typical components. The simulation study on the whole working perio... For a typical pressurized system with a novel dual-stage gas pressure reducing regulator,a system model is established with modular models of various typical components. The simulation study on the whole working period shows that the general trends and magnitudes of simulation curves are in agreement with experimental measured curves. As the key component in the pressurized system, the regulator is studied by a series of numerical simulations to reveal the influences of various structure parameters on its stability. Furthermore, the variable ranges which can guarantee the stability of regulator and system are obtained to provide guidance for design. The modeling and analysis approach can be applied to other systems and components. 展开更多
关键词 Dual-stage gas pressure reducing regulator Dynamic characteristics Finite volume method Numerical simulation Pressurized system Stability
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