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Raising medium function of environmental engineering by using life rubbish to produce carpet turf

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Journal of Environmental Sciences 2000年第4期12卷 498-505页

作者： DUO Li an, ZHAO Shu lan (College of Chemistry and Biology, Tianjin Normal University, Tianjin 300074, China) 天津师范大学天津 3 0 0 0 74

Abundant material with low cost was utilized to raise medium function of producing carpet turf by life rubbish. The results showed that the material used could strikingly raise water retentiveness and ventilating of medium. Through the determination of the effect of each growth index of several turfgrass, emergence density, plant height, root growth and individual plant′s net primary production were all positively related to the material′s amount mixed, showing that the mixture of material could promote turfgrass growth, further proving that the material used raised medium function of producing carpet turf by life rubbish and made most use of life rubbish resources. It provided a scientific base is for application of environmental engineering by using life rubbish to produce carpet turf. So the study had both important theoretic meaning and applied value.

关键词： life rubbish carpet turf medium function environmental engineering

Trend and seasonal variations of atmospheric CH_4 in Beijing

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Journal of Environmental Sciences 2000年第3期12卷 369-374页

作者： WANG Yue\|si, WANG Ming\|xing, LUO Dong\|mei, ZHENG Xun\|hua, ZHOU Li (Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China) 中科院大气物理所北京 1 0 0 0 2

The atmospheric CH\-4 in Beijing is still increasing, even though its increasing rate has significantly decreased from 1.76%/a during 1985—1989 to 0.50%/a during 1990—1997. The seasonal variation of CH\-4 concentration showed a double\|peak pattern, one peak appearing in winter and the other in summer. It is evident that the annually seasonal variations of atmospheric CH\-4 in Beijing are different. From 1986 to 1997, the atmospheric CH\-4 increased by 185 ppbv, 37% and 21% of which were due to the increase in winter and in summer, respectively. After 1993, the annually seasonal increasing rate of CH\-4 concentration in summer (due to emission from biogenic sources) is negative while the increasing rate in winter (due to emission from non\|biogenic sources) is positive about 25 ppbv/a. As a result, the increase of CH\-4 emission from non\|biogenic sources in winter is the major reason that caused the annually seasonal increasing rate from 1993 to 1997. The biogenic sources in Beijing are shrinking while the non\|biogenic ones (such as fossil fuel combustion) are enlarging.

关键词： atmospheric CH\-4 increasing rate seasonal variation annually seasonal variation

3D-QSAR Studies of Dimethoxyphenoxyphenoxy pyrimidines and Analogues

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Chinese Journal of Structural Chemistry 2000年第2期19卷 107-111页

作者： LI Ai Xiu WANG Jin Ling SU Hua Qing MIAO Fang Ming (Institute of Chemical Crystallography, Tianjin Normal University, Tianjin, 300074) 天津师范大学天津 3 0 0 0 74

Three dimensional quantitative structure activity relationships (3D QSAR) of a series of dimethoxyphenoxyphenoxypyrimidines and analogues which are known to be photosystem Ⅱ(PSⅡ)inhibitors have been studied using comparative molecular field analysis (CoMFA) method. The results suggest that the steric and electronic properties of substitutes at m position on the end phenyl ring have important influence on the Hill reaction inhibition.

关键词： D QSAR photosystem Ⅱinhibitor CoMFA

Global Perspectives:The COVID-19 Pandemic in 2020−2021 and Beyond

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China CDC weekly 2021年第7期3卷 142-143页

作者： Youngmee Jee Institut Pasteur Korea the who COVID-19 IHR Emergency Committee who R&D

While coronavirus disease 2019(COVID-19)cases have reached 100 million across the globe with more than 2 million deaths as at January 26,2021,over 50 countries have initiated vaccinations against the *** began within a year from January 12,2020,when the China CDC shared the new virus genomic sequence with the World Health Organization(who)and globally.

关键词： vaccination globally initiated

HISTORICAL PROCEDURES AND G-DSG METHOD BASED MANUFACTURING PLANNING

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Chinese Journal of Aeronautics 2000年第2期13卷 123-128页

作者：禹涌唐荣锡北京航空航天大学北京 1 0 0 0 83

Oriented to CAD/CAM seamless integration, this paper presents an idea for synthetically considering the qualitative history model, which represents the whole course of modeling, and the quantitative geometry model, which contains the extended Brep model, CSG and feature pedigree. History model building captures in background the dynamic interactive definition of engineering requirement and then explicitly conveys the original intention to successive application layers, which is conductive to the decision support of manufacturing planning in not only automatic geometry re constructing but also machining set up. G DSG theory as an earlier achievement is applied to generate the topology independent generalized mid model as an input to manufacturing planning, which is therefore simplified and its accuracy is simultaneously improved. Manufacturing planning lays emphasis on optimizing the mapping in both geometry and function from part itself to detail machining scheme. Comparatively, process planning pays more attention to the mapping to those items like tool, fixture, etc. Theoretically, such an idea is also beneficial to realizing the parametric NC machining trajectory generation and maintaining its dynamic consistency with the update of the design model.[WT5”HZ]

关键词： manufacturing planning manufacturing model unified machining domain part modeling history design model re construct generalized destructive solid geometry feature recognition

ALGEBRAIC TURBUL ENCE MODEL WITH MEM ORY FOR COMPUTATION OF 3-D TURBULENT BOUNDARY LAYERS WITH VALIDATION

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Chinese Journal of Aeronautics 2000年第2期13卷 65-74页

作者：忻鼎定北京航空航天大学北京 1 0 0 0 83

Additional equations were found based on experiments for an algebraic turbulence model to improve the prediction of the behavior of three dimensional turbulent boundary layers by taking account of the effects of pressure gradient and the historical variation of eddy viscosity, so the model is with memory. Numerical calculation by solving boundary layer equations was carried out for the five pressure driven three dimensional turbulent boundary layers developed on flat plates, swept wing, and prolate spheroid in symmetrical plane. Comparing the computational results with the experimental data, it is obvious that the prediction will be more accurate if the proposed closure equations are used, especially for the turbulent shear stresses.

关键词： boundary layer turbulence model with memory three dimensional computation experimental technique

Three industries and wastewater and COD discharge of Beijing

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Journal of Environmental Sciences 2000年第4期12卷 474-477页

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) 北京市环境保护所北京 1 0 0 0 3 北京师范大学北京 1 0 0 875

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.

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)

Ecological rebuilding and land reclamation in surface mines in Shanxi Province, China

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Journal of Environmental Sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1, BAI Zhong ke 2, GAO Lin 1 (1. Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China E\|mail: miaozewei@*** 2. Department of Soil Science, Shanxi Agricultural University Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in China. As land is under pressure in China, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

Crystal Structure And Magnetic Property of the Complex of Hydrogen-bonded Two-dimensional Layer Copper(Ⅱ)Acrylate with Trimethyl Phosphate

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Chemical Research in Chinese Universities 2000年第2期16卷 176-178页

作者： WANG Yaoyu SHI Qian YANG Bingqin GAO Yici SHI Qizhen 西北大学陕西西安 71 0 0 6 9 兰州大学甘肃兰州 7300 0 0

Copper carboxylate complexes play an important role in catalyzing the enzymatic activities, while the phosphate has especial use in DNA recognition. A layer structure complex of copper(II) acrylate was synthesized using hydrogen-bonded assemblies with trimethyl phosphate to determine its crystal structure and magnetic properties. The complex crystallized in a triclinic system. The temperature-dependent magnetic susceptibility was measured in the range of 5-300 K.

关键词： Copper(Ⅱ) acrylate Trimethyl phosphate Two-dimensional layer Crystal structure Magnetic property