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Ancient water wells reveal a prolonged drought in the lower Yellow River area about 2800 years ago

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Science Bulletin 2018年第20期63卷 1324-1327页

作者： Shiyong Yu Xuexiang Chen Xiuling Liu Zhen Fang Junfeng Guo Senyang Zhan Hui Fang Fahu Chen School of Geography Geomaticsand PlanningJiangsu Normal UniversityXuzhou 221116China Joint International Research Laboratory for Environmental and Social Archaeology 5handong Universityfinan 250100China Jinan Municipal Institute of Archaeology jinan 250062China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China

Proxy records from the North Atlantic realm reveal that large and rapid cooling known as the Bond events continued into the Holocene [1],repeatedly punctuating what is conventionally thought to have been a relatively stable climate.Given that the Holocene is the most recent interglacial period that has spurred the development of modern societies,scrutinizing climate variabil- ity during this period is important not only for predicting the trend of future climate changes,but also for better understanding the driving forces behind the rise and fall of ancient civilizations.

关键词： water wells drought Yellow River area

Tectonic analysis and petroleum significance of Cenozoic faults in Dongping-Niuzhong area in Altyn slope

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Petroleum Exploration and Development 2019年第5期46卷 983-990页

作者： DU Wei CHEN Yan WANG Zhendong BIAN Qing GUO Zhaojie Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationBeijing 100871China School of Earth and Space Sciences Peking UniversityBeijing 100871China Qinghai Oilfield Company PetroChinaDunhuang 736202China

The evolution process and petroleum significance of two groups of fault structures,the NW-SE trending and near EW trending ones in the Cenozoic of Dongping-Niuzhong area of the Altyn slope,Qaidam Basin,were investigated using high precision 3-D seismic data.The NW-SE faults were generated in Oligocene,causing the formation of a series of folds related to transpression faults in the Niuzhong and Dongping area.After the Miocene,with the continuous extension of the Altyn Tagh strike-slip fault zone,the EW trending faults began to develop massively in Altyn slope.The activity of near EW trending faults and large-scale uplift of the bedrock in the northern Niuzhong area shared most of the compression torsion in Niuzhong and Dongping area,consequently,the activity of NW-SE trending faults weakened significantly after the Miocene.Then good hydrocarbon source rocks developed in the inherited Jurassic sags.The faults were effective pathways for oil and gas migration in Dongping and Niuzhong areas,and the oil and gas charging time matched well with the formation period of the NW-SE trending faults and their related structures,making the fault-related anticlines favorable targets for oil and gas accumulation.The Niuzhong area has been less affected by the Cenozoic movement after the Miocene,and thus has better conditions for gas reservoir preservation.

关键词： Qaidam Basin Altyn slope Cenozoic tectonic analysis strike-slip fault petroleum significance Dongping-Niuzhong area

CFD model simulation of bubble surface area flux in flotation column reactor in presence of minerals

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International Journal of Mining Science and Technology 2018年第6期28卷 999-1007页

作者： A.R.Sarhan J.Naser G.Brooks Department of Mechanical and Product Design Engineering Swinburne University of TechnologyHawthornVictoria 3122Australia Department of Mechanical Engineering University of Anbar RamadiAnbar 31001Iraq

Bubble surface area flux(S_b) is one of the main design parameter in flotation column that typically employed to describe the gas dispersion properties, and it has a strong correlation with the flotation rate constant. There is a limited information available in the literature regarding the effect of particle type,density, wettability and concentration on Sb. In this paper, computational fluid dynamics(CFD) simulations are performed to study the gas–liquid–solid three-phase flow dynamics in flotation column by employing the Eulerian–Eulerian formulation with k-e turbulence model. The model is developed by writing Fortran subroutine and incorporating then into the commercial CFD code AVL FIRE, v.2014.This paper studies the effects of superficial gas velocities and particle type, density, wettability and concentration on Sband bubble concentration in the flotation column. The model has been validated against published experimental data. It was found that the CFD model was able to predict, where the response variable as indicated by R-Square value of 0.98. These results suggest that the developed CFD model is reasonable to describe the flotation column reactor. From the CFD results, it is also found that Sb decreased with increasing solid concentration and hydrophobicity, but increased with increasing superficial gas velocity. For example, approximately 28% reduction in the surface area flux is observed when coal concentration is increased from 0 to 10%, by volume. While for the same solid concentration and gas flow rate, the bubble surface area flux is approximately increased by 7% in the presences of sphalerite.A possible explanation for this might be that increasing solid concentration and hydrophobicity promotes the bubble coalescence rate leading to the increase in bubble size. Also, it was found that the bubble concentration would decrease with addition of hydrophobic particle(i.e., coal). For instance, under the same operating conditions, approximately 23% reduction in the bubble concentration is predicted wh

关键词： CFD Froth flotation Bubble surface area flux Solid properties Bubble concentration

粤港澳大湾区CO_(2)排放趋势、驱动因素及减排路径

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Engineering 2023年第4期23卷 138-148,M0007页

作者：周雅李柯君梁笙曾雪兰蔡宴朋孟靖单钰理关大博杨志峰 Key Laboratory of City Cluster Environmental Safety and Green Development Ministry of EducationSchool of EcologyEnvironment and ResourcesGuangdong University of TechnologyGuangzhou 510006China The Bartlett School of Construction and Project Management University College LondonLondon WC1E 7HBUK Integrated Research for Energy Environment and Society(IREES)Energy and Sustainability Research Institute GroningenUniversity of GroningenGroningen 9747 AGNetherlands Department of Earth System Sciences Tsinghua UniversityBeijing 100080China

粤港澳大湾区是我国为建设世界级城市群提出的国家战略,其CO_(2)排放趋势、社会经济驱动因素和减排路径对区域经济高质量发展具有重要意义。本研究编制了2000-2019年粤港澳大湾区CO_(2)排放清单,采用对数平均迪氏指数法探究CO_(2)排放... 详细信息

粤港澳大湾区是我国为建设世界级城市群提出的国家战略,其CO_(2)排放趋势、社会经济驱动因素和减排路径对区域经济高质量发展具有重要意义。本研究编制了2000-2019年粤港澳大湾区CO_(2)排放清单,采用对数平均迪氏指数法探究CO_(2)排放的关键驱动力。结果表明,粤港澳大湾区CO_(2)排放在2017年后明显放缓,已经与国内生产总值(GDP)增长脱钩。经济增长和能源强度分别是驱动和抑制粤港澳大湾区CO_(2)排放增加的主要因素。能源生产和重工业对粤港澳大湾区CO_(2)排放增长的推动作用降低,服务业正成为主要驱动力。粤港澳大湾区通过产业结构调整和升级实现低碳发展取得了显著成效。深圳和香港地区的产业升级以及深圳、广州和佛山的技术进步抑制了粤港澳大湾区CO_(2)排放增长。粤港澳大湾区各城市异质性增加了减排指标分配难度和制定区域碳中和路线图的复杂性。本研究提出了粤港澳大湾区城市分级减排策略和碳达峰碳中和建议,为制定粤港澳大湾区城市碳达峰和碳中和行动方案以及其他城市和地区的低碳发展提供了科学依据。

关键词： Guangdong-Hong Kong-Macao Greater Bay area CO_(2)emissions Driving factors Low-carbon development Carbon neutrality

Development of a model to simulate soil heavy metals lateral migration quantity based on SWAT in Huanjiang watershed,China

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Journal of Environmental Sciences 2019年第3期31卷 115-129页

作者： Pengwei Qiao Mei Lei Sucai Yang Jun Yang Xiaoyong Zhou Nan Dong Guanghui Guo Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing Key Laboratory of Remediation of Industrial Pollution Sites Environmental Protection Research Institute of Light Industry Comprehensive Institute of Geotechnical Investigation and Surveying Ltd.

Lateral transportation of soil heavy metals in rainfall events could significantly increase the scope of pollution. Therefore, it is necessary to develop a model with high accuracy to simulate the migration quantity of heavy metals. A model for heavy metal migration simulation was developed based on the SWAT(Soil and Water Assessment Tool) model. This model took into consideration the influence of soil p H value, soil particle size, runoff volume, sediment amount,concentration of water-soluble heavy metals dissolved in runoff and insoluble absorbed to the soil particles. This model was reasonable in Huanjiang watershed, Guangxi Zhuang Autonomous Region, south China, covering an area of 273 km^2. The optimal drainage area threshold was determined by analyzing the effects of watershed subdivision on the simulation results to ensure the simulation accuracy. The main conclusions of this paper were:(1) watershed subdivision could affect simulation migration quantity of heavy metals;(2) the quantity of heavy metals transported by sediment accounted for 97%–99% of the total migration quantity in the study watershed. Therefore, sediment played the most important role in heavy metal migration;(3) the optimal drainage area threshold percentage to ensure high simulation accuracy was determined to be 2.01% of the total watershed;(4) with the optimal threshold percentage, this model could simulate the migration quantity of As, Pb and Cd accurately at the total watershed and subwatershed level. The results of this paper were useful for identifying the key regions with heavy metal migration.

关键词： Soil heavy metal migration Simulation model Watershed subdivision Optimal drainage area threshold percentage Simulation accuracy

Comparison of mixing layer height inversion algorithms using lidar and a pollution case study in Baoding, China

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Journal of Environmental Sciences 2019年第5期31卷 81-90页

作者： Xiangguang Ji Cheng Liu Zhouqing Xie Qihou Hu Yunsheng Dong Guangqiang Fan Tianshu Zhang Chengzhi Xing Zhuang Wang Zeeshan Javed Jianguo Liu School of Environmental Science and Optoelectronic Technology University of Science and Technology of China Key Lab of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Hefei Institutes of Physical Science Chinese Academy of Sciences School of Earth and Space Sciences University of Science and Technology of China Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Anhui Province Key Laboratory of Polar Environment and Global Change University of Science and Technology of China

Beijing–Tianjin–Hebei area is suffering from atmospheric pollution from a long time. The understanding of the air pollution mechanism is of great importance for officials to design strategies for the environmental governance. Mixing layer height(MLH) is a key factor influencing the diffusion of air pollutants. It plays an important role on the evolution of heavy pollution events. Light detection and ranging(lidar), is an effective remote-sensing tool, which can retrieve high spatial and temporal evolution process within mixing layer(ML), especially the variation of MLH. There are many methods to retrieve MLH, but each method has its own applicable limitations. The Mie-lidar data in Beijing was firstly used to compare three different algorithms which are widely used under different pollution levels.We find that the multi-layer structure near surface may cause errors in the detection of mixing layer. The MLH retrieved based on image edge detection was better than another two methods especially under heavy polluted episode. Then we applied this method to investigate the evolution of the mixing layer height during a pollution episode in December2016. MLH at Gucheng county showed the positive correlation with the concentration of particulate matters during the start of this pollution episode. The elevated pollution level in Gucheng was not associated with MLH's decrease, and the significantly increased particulate matters raised the boundary layer, which trapped the pollutants near the surface.

关键词： Mixing layer Beijing–Tianjin–Hebei area Severe haze

Characterization of glutamatergic VTA neural population responses to aversive and rewarding conditioning in freely-moving mice

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Science Bulletin 2019年第16期64卷 1167-1178页

作者： Quentin Montardy Zheng Zhou Zhuogui Lei Xuemei Liu Pengyu Zeng Chen Chen Yuanming Liu Paula Sanz-Leon Kang Huang Liping Wang Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science Guangdong Provincial Key Laboratory of Brain Connectome and BehaviorCAS Center for Excellence in Brain Science and Intelligence TechnologyThe Brain Cognition and Brain Disease Institute(BCBDI)Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research InstitutionsShenzhen 518055China University of Chinese Academy of Sciences Beijing 100049China School of Physics the University of SydneySydney 2006Australia Centre for Integrative Brain Function the University of SydneySydney 2006Australia Department of Biomedical Sciences City University of Hong KongTat Chee AvenueKowloonHong KongSAR 999077China

The Ventral Tegmental area(VTA) is a midbrain structure known to integrate aversive and rewarding stimuli, but little is known about the role of VTA glutamatergic(VGluT2) neurons in these functions.Direct activation of VGluT2 soma evokes rewarding behaviors, while activation of their downstream projections evokes aversive behaviors. To facilitate our understanding of these conflicting properties, we recorded calcium signals from VTAVGluT2+ neurons using fiber photometry in VGluT2-cre mice to investigate how this population was recruited by aversive and rewarding stimulation, both during unconditioned and conditioned protocols. Our results revealed that, as a population, VTAVGluT2+neurons responded similarly to unconditioned-aversive and unconditioned-rewarding stimulation. During aversive and rewarding conditioning, the CS-evoked responses gradually increased across trials whilst the US-evoked response remained stable. Retrieval 24 h after conditioning, during which mice received only CS presentation, resulted in VTAVGluT2+ neurons strongly responding to CS presentation and to the expected-US but only for aversive conditioning. To help understand these differences based on VTAVGluT2+ neuronal networks, the inputs and outputs of VTAVGluT2+ neurons were investigated using Cholera Toxin B(CTB) and rabies virus. Based on our results, we propose that the divergent VTAVGluT2+ neuronal responses to aversion and reward conditioning may be partly due to the existence of VTAVGluT2+ subpopulations that are characterized by their connectivity.

关键词： Ventral Tegmental area Aversion Reward Conditioning Behavior

The medial preoptic area and the regulation of parental behavior

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Neuroscience Bulletin 2014年第5期30卷 863-865页

作者： Kumi O.Kuroda Michael Numan Research Unit for Affiliative Social Behavior RIKEN Brain Science Institute Rio Rancho

The preoptic area （POA） is located in the most anterior part of the hypothalamus and is bordered dorsally by the anterior commissure and anteroventrally by the nucleus of the diagonal band of Broca[1]. Accumulating evidence from developmental neurobiology suggests, however, that the POA may be a separate entity from hypothalamus, and may actually be part of the basal telencephalon[2,3]. Both the hypothalamus and POA are highly complex and heterogeneous areas, containing multiple nuclei, each of which has specific fundamental functions for survival. Among these, the POA contains nuclei involved in the regulation of blood osmolality and temperature （the median preoptic nucleus）, sleep （the ventrolateral preoptic and suprachiasmatic nuclei）, ovulation （gonadotropin-releasing hormone neurons scattered mainly in the ventral part of the POA）, male sexual behavior （the medial preoptic nucleus）, and parental behavior （the central part of the medial POA, cMPOA）.

关键词： MPOA The medial preoptic area and the regulation of parental behavior area

Use of the area of main influence to fix a relevant boundary for mining damages in Germany

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International Journal of Mining Science and Technology 2018年第1期28卷 79-83页

作者： Denise Müller Axel Preusse Faculty of Georesources and Materials Engineering Institute for Mine Surveying Mining Subsidence Engineering and Geophysics in Mining RWTH Aachen University

In 2010, the fracking discussion in Germany caused a number of changes in German law, which came into force in 2016.Especially the production of gas had to be regulated.With the legislation amendment, the Subsidence-area Mining Regulation has been revised, too.The changes expand the compensation of mining damages, especially to the extraction with drilling from the surface and underground storage.Although the Subsidence-area Mining Regulation has been revised, the area of main influence(subsidence of 10 cm)remains to determine a relevant boundary for mining damages.The determination and prediction of this boundary above caverns are presented in this paper.In addition, further elements of ground movements and their relevance to mine damages are analyzed.The usage of the area of main influence to fix a relevant boundary for mining damages does not correspond to the relevant elements of ground movements.A limit for differences in subsidence(tilt) or horizontal changes in length should be preferred to describe the relevance of mining damages on buildings.Furthermore, this paper outlines the meaning of using the area of main influence to fix a relevant boundary for mining damages.

关键词： Ground movements area of main influence Boundary for mining damages Subsidence-area mining regulation Subsidence detection Modeling above caverns