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Experimental and Theoretical investigation of Nonlinear Flow in Low Permeability Reservoir

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Experimental and Theoretical Investigation of Nonlinear Flow...

Experimental and Theoretical investigation of Nonlinear Flow in Low Permeability Reservoir

2011 International Conference on Energy and Environment(ICEE 2011)

作者： WANG Xue-wu YANG Zheng-ming SUN Yu-ping LIU Xue-wei Lang fang Branch Petro China Exploration and Development Research Institute

Taking low permeability cores of Daqing oilfield for example, the flow characteristics at low velocity were studied by using the self-designed micro-flux measuring instrument. Considering the throat distribution and capillary model, the thickness of fluid boundary layer under different pressure gradient was calculated, the mechanism and influencing factors of nonlinear percolation were discussed. The study showed that the percolation curve of ultra-low rocks was nonlinear, and apparent permeability was not a constant, which increased with pressure gradient. The absorption boundary layer decreased with the increase of pressure gradient, and changed significantly especially in low pressure gradient, which was the essence of bringing nonlinear percolation. The absorption boundary layer was also found to be impacted by surface property of rocks, and then impacted flow characteristics.

关键词： low permeability reservoirs percolation nonlinear absorption boundary layer capillary model

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Experimental and Theoretical Investigation of Nonlinear Flow...

Numerical investigation of the wind environment around tall buildings in a central business district

2011 2nd International Conference on Challenges in Environmental Science and Computer Engineering(CESCE 2011)

作者： WANG Xue-wu YANG Zheng-ming SUN Yu-ping LIU Xue-wei Lang fang Branch Petro China Exploration and Development Research Institute

Taking low permeability cores of Daqing oilfield for example,the flow characteristics at low velocity were studied by using the self-designed micro-flux measuring *** the throat distribution and capillary model,the thickness of fluid boundary layer under different pressure gradient was calculated,the mechanism and influencing factors of nonlinear percolation were *** study showed that the percolation curve of ultra-low rocks was nonlinear,and apparent permeability was not a constant,which increased with pressure *** absorption boundary layer decreased with the increase of pressure gradient,and changed significantly especially in low pressure gradient,which was the essence of bringing nonlinear *** absorption boundary layer was also found to be impacted by surface property of rocks,and then impacted flow characteristics.

关键词： Low permeability reservoirs percolation nonlinear absorption boundary layer capillary model

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Frontiers of Earth Science 2019年第4期13卷 848-858页

作者： Pingzhi fang Deqian ZHENG Ming GU Haifeng CHENG Bihong ZHU Shanghai Typhoon Institute of China Meteorological Administration Shanghai 200030China School of Civil Engineering and Architecture Henan University of TechnologyZhengzhou 450001China State Key Laboratory for Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shanghai investigation Design&Research Institute Co.Ltd.Shanghai 200335China

The wind environment around tall buildings in a central business district(CBD)was numerically *** district covers an area of-^4.0 km2 and features a high density of tall *** this study,only buildings taller than 20 m were considered,resulting in 173 tall buildings in the *** numerical investigation was realized using the commercial computational fluid dynamics code FLUENT with the realizable A-6:turbulence *** efforts were made to maintain inflow boundary conditions throughout the computational *** reliability of the numerical method was validated using results from an experimental investigation conducted in the core area of the CBD(〜1.5 km2).Experimental and numerical investigations of wind speed ratios at the center of the three tallest buildings in the CBD agree within an uncertainty factor of *** the experimental and numerical results show that wind speed ratios in the wind field with exposure category D are higher than those from the wind field with exposure category *** on the above validation work,the wind environment around tall buildings in the whole CBD was then investigated by numerical *** flow phenomena and patterns,such as stagnation points,shielding effects,separation flow,and channeling flow,were identified around the tall *** pedestrianlevel wind environment around tall buildings in the CBD was further evaluated using nearby meteorological wind *** evaluation results show that some pedestrian activities,such as sitting at the center of the three tallest buildings,are unadvisable when the wind blows from the south-east.

关键词： wind environment pedestrian-level wind computational fluid dynamics wind speed ratio central business district

Insights into multisource sludge distributed in the Yangtze River basin, China: Characteristics,correlation, treatment and disposal

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Journal of Environmental Sciences 2023年第4期126卷 321-332页

作者： Yiqun Guo Hui Gong Wenjing Shi Ning fang Yaqin Tan Weiqi Zhou Jialiang Huang Lingling Dai Xiaohu Dai Yali Guo State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai investigation Design&Research Institute Co.LtdShanghai 200050China YANGTZE Eco-Environment Engineering Research Center(Shanghai) China Three Gorges CorporationShanghai 200050China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Sludge is the by-product of wastewater treatment process. Multisource sludge can be defined as sludge from different sources. Based on the sludge properties of five typical cities in the Yangtze River basin, including Jiujiang, Wuhu, Lu’an, Zhenjiang and Wuhan, this study investigated and summarized the characteristic variations and distribution differences of multiple indicators and substances from municipal sludge, dredged sludge, and river and lake sediments. The results demonstrated pH of multisource sludge was relatively stable in the neutral range. Organic matter and water content among municipal sludge were high and varied considerably between different wastewater treatment plants. Dredged sludge had an obviously higher sand content and wider particle distribution, which could be considered for graded utilization depending on its size. The nutrients composition of river and lake sediments was usually stable and special, with lower nitrogen and phosphorus content but higher potassium levels. The sources of heavy metals and persistent organic pollutants in multisource sludge were correlated, generally much higher among municipal sludge than dredged sludge and river and lake sediments, which were the most important limitation for final land utilization. Despite various properties of multisource sludge, the final fate and destination have some overall similarities, which need to be supplemented and improved by standards and laws. The study provided a preliminary analysis of suitable technical routes for municipal sludge, dredged sludge, river and lake sediments based on their different characteristics respectively, which was of great significance for multisource sludge co-treatment and disposal in the future of China.

关键词： Multisource sludge Basic characteristics Potential correlation Treatment and disposal Heavy metals Persistent organic pollutants

中国淡脉隧蜂属指名亚属三新种(膜翅目:蜜蜂总科,隧蜂科)

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昆虫学报 1992年第3期35卷 346-349页

作者：范建国 P.ANDREAS WERNER EBMER 中国科学院动物研究所北京100080 Kirchenstrasse 9 A-4040 Puchenau bei Linz Austria

本文记述中国淡脉隧蜂属指名亚属Lasioglossum(Lasioglossum)三新种。所有正模、配模和大多数副模标本保存于中国科学院动物研究所,少量副模标本保存于奥地利国P. Andreas Werner Ebmer处。

关键词：隧蜂科淡脉隧蜂属指名亚属新种

A family net of giant pandas in the Tangjiahe Natural Reserve:Assessment of current individual migration

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Chinese Science Bulletin 2005年第17期50卷 1879-1886页

作者： WAN Qiuhong fang Shengguo LI Jianguo ZHANG Liming OU Weifu XIAN fanghai CHEN Wanli College of Life Sciences State Conservation Center for Gene Resources of Endangered Wildlife and Key Laboratory of Conservation Genetics and Reproductive Biology for Endangered Wild Animals of Ministry of Education Zhejiang University Hangzhou 310029 China Forestry Department of Sichuan Province Chengdu 610081 China Sichuan Bureau for Wildlife Resource investigation Conservation and Management Chengdu 610082 China Tangjiahe Natural Reserve Qingchuan 628109 China

In the present study, formalin-fixed feces, oli-gonucleotide fingerprinting and SRY-gene based sexing were used to construct a family net for giant pandas in the Tang-jiahe Natural Reserve and to assess contemporary gene flow (migration) in this population. A total of 124 fecal samples were attributed to 37 individuals (22 females and 15 males) that were then analyzed for family relationships. Based on DNA fingerprints, the deduced family net revealed the fol-lowing facts: (i) First-order relatives possessed similarities from 50% to 90%, and similarities between unrelated indi-viduals or distant relatives were as high as 77%, indicating that the Tangjiahe pandas are characterized by high genetic similarity; (ii) 15 matings were identified and 5 ones oc-curred between close relatives, implying that there is poten-tial for inbreeding to impact the pandas; (iii) four mating pairs and 5 offspring presented long distance migrations, demonstrating the intra-reserve habitat is continuous; (iv) four pairs of full sibs (also female-male dyads) dispersed short distance and all of them gave birth to highly inbred offspring, reflecting long distance migration is vital for in-breeding avoidance; (v) 17 adult individuals dispersed short or moderate distance and formed three clusters on the land-scape, indicating that it is necessary to find out whether there is a negative factor impacting the pandas.

关键词： DNA 生物技术同系繁殖植物移植分散模式

Influence of China’s Overseas power stations on the electricity status of their host countries

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International Journal of Digital Earth 2022年第1期15卷 416-436页

作者： Xumiao Gao Mingquan Wu Chao Li Zheng Niu fang Chen Wenjiang Huang State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Jinan Geotechnical investigation and Surveying Institute JinanPeople’s Republic of China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China

China has become a major investor and constructor of electrical power plants in developing ***,the impacts of China's overseas power stations(COPSs)on the developing countries hosting them are poorly ***,a novel method is proposed to evaluate the influence of COPSs in 80 host ***,their electricity consumption from 1971 to 2017 was estimated using data provided by the World Bank,International Energy Agency,and World Resources *** analysis was then used to predict consumption from 2018 to ***,three parameters were used to evaluate the influences of *** results show that:1)COPSs significantly increased the total installed capacity of 35 of the host countries by>20%.2)The power generated by COPSs is greater than the growing demands of 32 of the host countries.3)COPSs will increase the per capita electricity consumption of all 80 host countries.4)Among the 437 COPSs existing in 2000–2019,renewable power plants(including hydropower)were most numerous,accounting for 51.3%.This proportion increased significantly after 2013 and renewable plants will continue to dominate as China will no longer invest in new coal-fired power stations after 2021.

关键词： Influence of China’s overseas power stations Belt and Road Initiative electricity status renewable sources of energy SDG7

Methodological study of coastal geological hazard assessment based on GIS

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Journal of Groundwater Science and Engineering 2015年第1期3卷 77-85页

作者： LIU Jun CHENG Jian-mei JIANG fang-yuan Land Resources Bureau of Changzhou City Changzhou Geoscience & Living Environment Institute School of Environmental Studies China University of Geosciences Shenzhen investigation & Research Institute Co Ltd

The current researches on risk assessment of geological disasters mainly focus on unexpected disasters such as collapses, landslides and mud-rock flows etc. As the convergence zone of land and sea, coastal zone is the most active and complex area of interactions of lithosphere, hydrosphere, atmosphere, biosphere and anthroposphere. The ecological environment of coastal zone is very fragile, so further systematical research on coastal geological hazard assessment and prevention is in urgent need. The author begins with the definition and research contents and selects three typical coastal geological disasters, namely, the seawater intrusion, coastline change and sea-level rise as the objects of study. The systematic analysis and study on assessment system and methods are conducted, hazard assessment factors are selected, and a completely set of coastal disaster assessment system is established based on the technique of GIS. We took Bao’an District of Shenzhen City as an example and carried out a case study.

关键词： Costal zone Geological hazard GIS Seawater intrusion Coastline change Sea-level rise

A labor-free index-guided semantic segmentation approach for urban vegetation mapping from high-resolution true color imagery

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International Journal of Digital Earth 2023年第1期16卷 1640-1660页

作者： Peng Zhang Cong Lin Shanchuan Guo Wei Zhang Hong fang Peijun Du Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural ResourcesSchool of Geography and Ocean ScienceNanjing UniversityNanjingPeople’s Republic of China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application NanjingPeople’s Republic of China c Nanjing Research Institute of Surveying Mapping&Geotechnical InvestigationCo.LtdNanjingPeople’s Republic of China

Accurate and timely information on urban vegetation(UV)can be used as an important indicator to estimate the health of *** to the low cost of RGB cameras,true color imagery(TCI)has been widely used for high spatial resolution UV ***,the current index-based and classifier-based UV mapping approaches face problems of the poor ability to accurately distinguish UV and the high reliance on massive annotated samples,*** address this issue,an index-guided semantic segmentation(IGSS)framework is proposed in this ***,a novel cross-scale vegetation index(CSVI)is calculated by the combination of TCI and Sentinel-2 images,and the index value can be used to provide an initial UV ***,reliable UV and non-UV samples are automatically generated for training the semantic segmentation model,and then the refined UV map can be *** experimental results show that the proposed CSVI outperformed the existingfive RGB vegetation indices in highlighting UV cover and suppressing complex backgrounds,and the proposed IGSS workflow achieved satisfactory results with an OA of 87.72%∼88.16%and an F1 score of 87.73%∼88.37%,which is comparable with the fully-supervised method.

关键词： Urban vegetation mapping Sustainable Development Goals(SDGs) cross-scale vegetation index(CSVI) semantic segmentation high-resolution true color imagery(TCI)