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Quantitative evaluation of air pollution in transport strategic environmental assessment:a case study based on uncertainty analysis and graphic information system technology

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第5期11卷 370-381页

作者： Hong-tao BAI Hui-zhi WANG He XU Tan ZHU Research Center for Strategic Environmental Assessment Nankai University Tianjin 300071 China

Although the impact of road transport on urban air quality has achieved a high profile in China,still greater attention is required as it has not yet been considered fully even in relation to the road network linking cities and urban areas. Strategic environmental assessment (SEA) is a systematic and comprehensive process for evaluating the environmental impacts of a policy,plan or program in publicly accountable decision-making. Air pollution has been recognized as a significant issue in most transport SEA practices. The Strategic Environmental Assessment of the Hubei Road Network Plan (2002-2020) (HRNP) was introduced as one of the World Bank's pilot SEA projects. An effective framework was developed to investigate the functional relationship between the road network and its potential air pollutant emissions. In this study,two indicators were identified:emission intensity/ inventory of pollutants and the spatial distribution of the most polluted areas. Because strategic actions are inherently nebulous and data quality is often disappointing,three alternative scenarios were employed to address uncertainties and data/scale issues. Calculations were made using emission models and results were analyzed with the help of statistical tools and the geographic information system (GIS). The results from the project implementation and the feedback from the World Bank have both shown that the proposed framework is effective in the transport SEA process.

关键词： Air pollution Transport strategic environmental assessment (SEA) Quantitative evaluation Uncertainty

Meromorphic Functions of Finiteφ-order and Linear Askey-Wilson Divided Difference Equations

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Acta Mathematica Sinica,English Series 2022年第2期38卷 371-383页

作者： Hui YU Janne HEITTOKANGAS Jun WANG zhi tao WEN Department of Physics and Mathematics University of Eastern FinlandP.O.Box 11180101 JoensuuFinland School of Mathematical Sciences Fudan UniversityShanghai 200433P.R.China Department of Mathematics Shantou UniversityShantou 515063P.R.China

The growth of meromorphic solutions of linear difference equations containing Askey-Wilson divided difference operators is ***φ-order is used as a general growth indicator,which covers the growth spectrum between the... 详细信息

关键词： Askey-Wilson divided difference operator Askey-Wilson divided difference equation lemma on the logarithmic

Triggering mechanism and dynamic process of water-rock flow in Nanfen waste dump in 2010

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Journal of Mountain Science 2021年第10期18卷 2565-2579页

作者： CAO Chun-hui FENG Ji-li tao zhi-gang State Key Laboratory for Deep Geomechanics and Underground Engineering China University of Mining and Technology BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology BeijingBeijing 100083China

Water-rock flow is a kind of debris flow with more coarse particles and low viscosity, which occurs in many areas of the world. In this work, the water-rock flow that occurred on May 24, 2010, at Nanfen’s open-pit mine of China was investigated by combining field investigation, meteorological and hydrological survey with numerical simulation to understand its triggering mechanism and dynamic process. The field data shows that the short-term high-intensity rainfall is the most direct inducement to trigger water-rock flow in the waste dump. The loose shallow gravel soil and the V-shaped valley with a certain slope provide the necessary conditions of the occurrence of water-rock flow in the waste dump. Moreover, the possibility criterion of water-rock flow is presented by analyzing the historical rainfall data. In addition, the smoothed particle hydrodynamics(SPH) method was employed to simulate the waterrock flow under the conditions of Newtonian fluid with uniform distribution of water and coarse-grained materials. The simulating results show that the flow distance, velocity, shape, and deposition profile of water-rock flow are in good agreement with the field observation. The present work is beneficial to the risk assessment and mitigation design of water-rock flow disaster in the waste dump.

关键词： Water-rock flow Waste dump Triggering mechanism Smoothed particle hydrodynamics Rainfall intensity

Turbulent characteristics and rotation correction of wall function in rotating channel with high local rotation parameter

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Chinese Journal of Aeronautics 2018年第10期31卷 1985-1999页

作者： zhi tao Huijie WU Ruquan YOU Haiwang LI Kuan WEI National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang University Collaborative Innovation Center for Advanced Aero-Engine Beihang University

The turbulent fluctuation and the rotation correction of wall function law are investigated in the entrance section of a rotating channel. The one-dimensional hot wire probe and the X-type probe are utilized to measure the boundary layer at four streamwise stations. Through the analysis on the boundary layer near the leading side and trailing side, it is found that the turbulent fluctuation is promoted in the trailing side whereas suppressed in the leading side. This difference is attributed to the Coriolis instability near the trailing side. In addition, considering the local rotation parameter Rc, whose maximum absolute value is 0.014, is larger than that in previous research, whose maximum value is 0.007, the whole process of the relaminarization is captured. To understand this phenomenon better, the effects of the generation term and the Coriolis term in the transport equation of the Reynolds stress are discussed. In addition, the rotation correction of the viscous-Coriolis region and the Coriolis region are discussed, a new revising method for the wall function is proposed.

关键词： Coriolis force Entry section Relaminarization Rotating channel Turbulence

Comparison of choroidal thickness measured by two methods

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International Journal of Ophthalmology(English edition) 2012年第3期5卷 348-353页

作者： Wei Chen zhi-tao Wang and Hong Zhang Department of Ophthalmology Tongji Hospital Wuhan 430030 Hubei Province China

AIM: To examine the profile of the choroidal thickness (CT) in healthy myopia subjects and emmetropic participants by Heidelberg Eye explore software and Image 3 software so as to compare the agreement and reproducibility of the two methods. METHODS: Thirty-six study participants (36 eyes) were enrolled in this research. The fovea and parafoveal region (the region of 6mm diameter of the fovea as center) of the images were selected by spectral domain optic coherence tomography (SD-OCT). The choroidal thickness was measured manually by the Heidelberg Eye explore software (version 5.***.3.0, Heidelberg Engineering) with a vertical line and the Image 3 software with a line vertical to the retinal pigment epithelial layer. The agreement and reproducibility of the two methods were described by the Bland-Altmann analysis. RESULTS: As compared with Heidelberg Eye explore software (39.9186), the repeatability coefficient is lower calculated by Image 3 software (27.3525). The Bland-Altmann analysis showed that the limits of 95% CI of agreement analysis is -18.437-63.949 mu m and the upper limits of the precision of the 95% CI of agreement is between 16.102 and 111.796 mu m and the lower limits is range from -66.29-21.41 mu m, which reflected a great variations of the difference. CONCLUSION: The repeatability and agreement of measurement implied by Image 3 software was better than the Heidelberg Eye explore software. The Image 3 software should be used for measuring the choroidal thickness in future study in China.

关键词： choroid optic coherence tomography investigative techniques

Synthesis of α-fluoro-β-amino acids via the Reformatsky reaction of chiral N-tert-butylsulfinylimines with ethyl bromofluoroacetate

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Chinese Chemical Letters 2011年第8期22卷 919-922页

作者： zhi tao Jing Yan GenHuang Feng Ling Qing College of Chemistry Chemical Engineering and Biotechnology Donghua University Shanghai 201620 China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Treatment of chiral N-tert-butyl sulfinylimines with ethyl bromofluoroacetate in the presence of activated Zn dust in THF afforded the α-fluoro- β-amino acid derivatives in good yields（70-86%） and moderate diaster... 详细信息

关键词： Fluorinated amino acids Reformatsky reaction N-tert-Butyl sulfinylimine

Eco-geological environment quality assessment based on multi-source data of the mining city in red soil hilly region, China

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Journal of Mountain Science 2022年第1期19卷 253-275页

作者： ZHAO Fei-fei HE Man-chao WANG Yun-tao tao zhi-gang LI Chun State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 10083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 10083China Beijing Institute of Geology Beijing 100010China Key Laboratory of Geotechnical and Underground Engineering Tongji UniversityMinistry of EducationShanghai 200082China Beijing Baodiyilian Geological Exploration Engineering Technology Co.LTD Beijing 100010China

High-intensity and large-scale resource development seriously threatens the fragile ecological environment in the red soil hilly region in southern China. This paper analyzes the eco-geological environmental problems and factors affecting Ganzhou, a mining city in the red soil hilly region,based on field survey and literature. The ecogeological environment quality(EGEQ) assessment system, which covered 11 indicators in physical geography, mining development, geological hazards,as well as water and soil pollution, was established through multi-source data utilization such as remote sensing images, DEM(Digital Elevation Model), field survey and on-site monitoring data. The comprehensive weight of each indicator was calculated through the Analytic Hierarchy Process(AHP) and entropy method. The eco-geological environment assessment map was developed by calculating the EGEQ value through the linear weighted method. The assessment results show that the EGEQ was classified into I-V grades from excellent to worse, among which, EGEQ of I-II accounted for 29.88%, EGEQ of III accounted for 32.35% and EGEQ of IV-V accounted for 37.77%;the overall EGEQ of Ganzhou was moderate. The assessment system utilized in this research provides scientific and accurate results, which in turn enable the proposal of some tangible protection suggestions.

关键词： Eco-geological environment assessment Mining city Red soil hilly region AHP Entropy method

Super Weak Compactness and Uniform Eberlein Compacta

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Acta Mathematica Sinica,English Series 2017年第4期33卷 545-553页

作者： zhi tao YANG Yu Feng LU Qing Jin CHENG School of Mathematical Sciences Dalian University of Technology School of Mathematical Sciences Qinzhou University School of Mathematical Sciences Xiamen University

We prove that a topological space is uniform Eberlein compact iff it is homeomorphic to a super weakly compact subset C of a Banach space such that the closed convex hull coC of C is super weakly compact. We also show that a Banach space X is super weakly compactly generated iff the dual unit ball B;of X;in its weak star topology is affinely homeomorphic to a super weakly compactly convex subset of a Banach space.

关键词： Banach space uniform Eberlein compactas super weak compactness

Theoretical Studies on Dehydrogenation Reactions in Mg2（BH4）2（NH2）2 Compounds

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Chinese Journal of Chemical Physics 2012年第6期25卷 676-680,I0003页

作者： Zheng Chen Zhe-ning Chen An-an Wu Guo-tao Wu zhi-tao Xiong Ping Chen Xin Xu State Key Laboratory for Physical Chemistry of Solid Surface Fujian Provincial Key Laboratoryof Theoretical and Computational Chemist04 College of Chemistry and Chemical Engineering XiamenUniversity Xiamen 361005 China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China MOE Laboratory for Computational Physical Science Shanghai Key Laboratory of Molecular Catalysisand Innovative Materials Department of Chemistry Center of Chemistry for Energy Materials FudanUniversity Shanghai 200433 China

Borohydrides have been recently hightlighted as prospective new materials due to their high gravimetric capacities for hydrogen storage. It is, therefore, important to under- stand the underlying dehydrogenation mechanisms for further development of these ma- terials. We present a systematic theoretical investigation on the dehydrogenation mecha- nisms of the Mg2（BH4）2（NH2）2 compounds. We found that dehydrogenation takes place most likely via the intermolecular process, which is favorable both kinetically and thermo- dynamically in comparison with that of the intramolecular process. The dehydrogenation of Mg2（BH4）2（NH2）2 initially takes place via the direct combination of the hydridie H in BH4 and the protie H in NH2-, followed by the formation of Mg-H and subsequent ionic recombination of Mg-Hδ-…Hδ＋-N.

关键词： Hydrogen storage Density functional theory Metal borohydride