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Three industries and water consumption of Beijing 被引量:2
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作者 Wang Hong rui Institute of Environmental Sciences,Beijing Normal University,Beijing 100875,China Wang Yan Beijing Municipal Research Institute of Environmental Protection,Beijing 100037,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第2期54-61,共8页
Beijing has been experiencing a severe shortage of water. At present serious wastes of water resources result from the unreasonable structure of water uses in various industries sectors. The current conditions of t... Beijing has been experiencing a severe shortage of water. At present serious wastes of water resources result from the unreasonable structure of water uses in various industries sectors. The current conditions of the municipal water use structure and its changes in the industrial sectors were analysed and discussed in terms of the indicators, such as direct water use coefficient, complete water use coefficient, water use multiplier and water reuse rate, by taking a year of 1990s as the base year. Some response strategies for water conservation have been studied and the corresponding recommendations were put forward. All of these have provided a basis for coordinating the relationship between aquatic environment and economic growth in this city, establishing a system for rational utilization of water resources, and promoting the implementation of a strategy for sustainable development. 展开更多
关键词 direct water use coefficient complete water use coefficient water use multiplier water reuse rate.
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High frequency S wave envelope synthesis using a multiple non-isotropic scattering model: application to aftershocks from the 2008 Wenchuan earthquake 被引量:1
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作者 Lin Gao Jing Yueling Li Jianbo 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第2期185-194,共10页
Based on the formulation of a multiple non-isotropic scattering process, a characteristic source time is introduced to define the initial impulse width of energy density at the source. An analytical expression of the ... Based on the formulation of a multiple non-isotropic scattering process, a characteristic source time is introduced to define the initial impulse width of energy density at the source. An analytical expression of the initial intensity spectral density of a seismic wave is incorporated into the integral equation of seismic wave energy density. And, a recursive formula of Green's function is derived to obtain the higher order Green's function, which is included to describe the stronger non-isotropic scattering process. Then, the effect of the scattering pattern on the energy density envelope is investigated by the modified scattering theory. Significant differences arc found in the decay of the energy density envelopes with distances using different scattering patterns. The envelope synthesized by the forward dominated scattering pattern is larger than the results obtained by the isotropic and backward dominated scattering pattern. Different scattering patterns are also used to fit the observation data from the aftershocks of the 2008 Wenchuan earthquake. It is concluded that the envelopes synthesized by the forward scattering pattern can match the data better than the isotropic and backward dominated scattering cases, and a new interpretation of the coda wave is given. Finally, using the forward dominated scattering pattern, the envelope broadening of the observed data is reproduced. 展开更多
关键词 non-isotropic scattering coda wave envelope broadening energy transport theory (radiative transfer theory) directional scattering coefficient ground motion
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Three industries and wastewater and COD discharge of Beijing 被引量:1
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作者 WANG Yan 1, WANG Hong rui 2, NING Da tong 2 (1. Beijing Municipal Research Institute of Environmental Protection, Beijing 100037, China 2. Institute of Environmental Sciences, Beijing Normal University, Beijing 100875, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第4期474-477,共4页
With the swift development of economy, the water quality of Beijing is becoming worse day by day and hampers the sustainable development obviously. In this paper, the current conditions of the municipal wastewater str... With the swift development of economy, the water quality of Beijing is becoming worse day by day and hampers the sustainable development obviously. In this paper, the current conditions of the municipal wastewater structure in the industrial sectors are analysed and discussed in terms of the indicators, such as direct wastewater\|discharge coefficient, complete wastewater\|discharge coefficient, direct discharge coefficient of COD and complete discharge coefficient of COD, by taking a year of 1990s as the base year. Some countermeasures are studied and the corresponding recommendations are put forward in order to improve the water environment in Beijing. This provides a scientific ground for coordinating the relationship between the aquatic environment and economic growth in this city. 展开更多
关键词 direct wastewater discharge coefficient (DWDC) complete wastewater discharge coefficient (CWDC) direct discharge coefficient of COD(DDC of COD) complete discharge coefficient of COD (CDC of COD)
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3D digital-image correlation insight into generalized relaxation behavior of sandstone under stress and pore pressure coupling
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作者 Cancan Chen Heping Xie +4 位作者 Jiang Xu Seisuke Okubo Shoujian Peng Cunbao Li Minghui Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2024年第7期2516-2536,共21页
The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stres... The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stress in creep or constant strain in relaxation is not usually attained in natural geological systems.Therefore,generalized relaxation tests that explore the simultaneous changes of stress and strain with time under different stress levels with constant pore-water pressure are conducted in this study.The results show that in area Ⅰ,area Ⅱ,and area Ⅲ,the stress and strain both change synchronously with time and show similar evolutionary laws as the strain-time curve for creep or the stress-time curve for relaxation.When the applied stress level surpasses the δ_(ci) or δ_(cd) threshold,the variations in stress and strain and their respective rates of change exhibit a significant increase.The radial deformation and its rate of change exhibit greater sensitivity in response to stress levels.The apparent strain deforms homogeneously at the primary stage,and subsequently,gradually localizes due to the microcrack development at the secondary stage.Ultimately,interconnection of the microcracks causes the formation of a shear-localization zone at the tertiary stage.The strain-time responses inside and outside the localization zone are characterized by local strain accumulation and inelastic unloading during the secondary and tertiary stages,respectively.The width of the shear-localization zone is found to range from 4.43 mm to 7.08 mm and increased with a longer time-to-failure.Scanning electron microscopy(SEM)reveals a dominant coalescence of intergranular cracks on the fracture surface,and the degree of physiochemical deterioration caused by water-rock interaction is more severe under a longer lifetime.The brittle sandstone’s time-dependent deformation is essentially controlled by microcrack development during generalized relaxation,and its expectancy-life is determined by its initial microstructural state and the rheological path. 展开更多
关键词 Generalized relaxation Stress level direction coefficient Major-strain field Microcrack damage Stress threshold
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Study on Trends of Change in Direct Input Coefficients of China 被引量:1
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作者 GUO Ju\|e Shaanxi Institute of Finance and Economics, Xi′an 710061, China 《Systems Science and Systems Engineering》 CSCD 2000年第1期61-64,共4页
The objective of this paper is to study the trends of change in direct input coefficients of China. We reconstructed a time series of input\|output tables of China with 18 sectors for 1981, 1987, 1990, 1992 and 1995 a... The objective of this paper is to study the trends of change in direct input coefficients of China. We reconstructed a time series of input\|output tables of China with 18 sectors for 1981, 1987, 1990, 1992 and 1995 at constant prices and current prices, and the tables for developed region, middle developed region and underdevelopd region. On the basis of these tables we found seven important trends on change in China′s direct input coefficients. 展开更多
关键词 input\|output table at constant prices trends of change in direct input coefficients
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