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Aerosol Optical Properties and Its Radiative Forcing over Yulin, China in 2001 and 2002

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Advances in Atmospheric Sciences 2009年第3期26卷 564-576页

作者：车慧正张小曳 Stephane ALFRARO Bernadette CHATENET Laurent GOMES 赵剑琦 Key Laboratory of Atmospheric Chemistry Centre for Atmosphere Watch and ServicesChinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081 Laboratoire Inter-Universitaire des Systmes Atmosphriques Universit Paris Ⅶ/Paris Ⅻ94010 Crteil Cedex France centre National de la Recherche Scientifique Meto-France/CNRM/GMEI/MNPCA31057ToulouseFrance State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029

The aerosol optical properties and direct radiative forcing over the Mu Us desert of northern China, acquired through a CE318 sunphotometer of the ground-based Aerosol Robotic Network （AERONET）, are analyzed. The seasonal variations in the aerosol optical properties are examined. The effect of meteorological elements （pressure, temperature, water vapor pressure, relative humidity and wind speed） on the aerosol optical properties is also studied. Then, the sources and optical properties under two different cases, a dust event and a pollution event, are compared. The results show that the high aerosol optical depth （AOD） found in Yulin was mostly attributed to the occurrence of dust events in spring from the Mu Us desert and deserts of West China and Mongolia, as well as the impacts of anthropogenic pollutant particles from the middle part of China in the other seasons. The seasonal variation and the probability distribution of the radiative forcing and the radiative forcing efficiency at the surface and the top of the atmosphere are analyzed and regressed using the linear and Gaussian regression methods.

关键词： aerosol optical properties aerosol radiative forcing Mu Us desert China

THS-GWNN:a deep learning framework for temporal network link prediction

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Frontiers of Computer Science 2022年第2期16卷 174-176页

作者： Xian MO Jun PANG Zhiming LIU College of Computer&Information Science Southwest UniversityChongqing 400715China Faculty of Science Technology and Medicine&Interdisciplinary Centre for SecurityReliability and TrustUniversity of LuxembourgEsch-sur-Alzette L-4364Luxembourg

1 Introduction and main contributions Link prediction for temporal networks aims to evaluate the likelihood of the future linkage among nodes,which has significant applications in social networks,biological networks and traffic analysis[1],*** embedding[2]is an important analytical tool for temporal network link prediction,which helps us better understand network evolution[3].How to encode high-dimensional and non-Euclidean network information is a crucial problem for node embedding in temporal *** of the challenges is to reveal the spatial structure at each timestamp and the temporal property over time[4].Some existing work[5]shows that extracting the spatial relation of each node can be used as a valid feature representation for each ***,the emergence of deep learning techniques[4,5]brings new insights for learning temporal properties,but most models using deep learning still fail to achieve satisfying prediction accuracy.

关键词： network prediction networks

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Effect of Methane Emission Increases in East Asia on Atmospheric Circulation and Ozone

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Advances in Atmospheric Sciences 2015年第12期32卷 1617-1627页

作者： SHANG Lin LIU Yi TIAN Wenshou ZHANG Yuli Shandong Province Climate centre Key Laboratory of the Middle Atmosphere and Global Environmental Observation Institute of Atmospheric PhysicsChinese Academy of Sciences Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou University

We used a fully coupled chemistry-climate model （version 3 of the Whole Atmosphere Community Climate Model, WACCM3） to investigate the effect of methane （CH4） emission increases, especially in East Asia and North America, on atmospheric temperature, circulation and ozone （03）. We show that CH4 emission increases strengthen westerly winds in the Northern Hemisphere midlatitudes, accelerate the Brewer-Dobson （BD） circulation, and cause an increase in the mass flux across the tropopause. However, the BD circulation in the tropics between 10°S and 10°N at 100 hPa weakens as CH4 emissions increase in East Asia and strengthens when CH4 emissions increase in North America. When CH4 emissions are increased by 50% in East Asia and 15% globally, the stratospheric temperature cools by up to 0.15 K, and the stratospheric 03 increases by 45 ppbv and 60 ppbv , respectively. A 50% increase of CH4 emissions in North America （with an amplitude of stratospheric 03 increases by 60 ppbv） has a greater influence on the stratospheric 03 than the same CH4 emissions increase in East Asia. CH4 emission increases in East Asia and North America reduce the concentration of tropospheric hydroxyl radicals （4% and 2%, respectively） and increase the concentration of mid-tropospheric 03 （5% and 4%, respectively） in the Northern Hemisphere midlatitudes. When CH4 emissions increase in East Asia, the increase in the tropospheric 03 concentration is largest in August. When CH4 emissions increase in North America, the increase in the 03 concentration is largest in July in the mid-troposphere, and in April in the upper troposphere.

关键词： CH4 temperature Brewer-Dobson circulation O3

Magneto-Elastic Coupling in a Sinusoidal Modulated Magnet Cr_(2)GaN

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Chinese Physics Letters 2022年第9期39卷 72-75页

作者： Hui-Can Mao Yu-Feng Li Qing-Yong Ren Mi-Hai Chu Helen E.Maynard-Casely Franz Demmel Devashibhai Adroja Hai-Hu Wen Yin-Guo Xiao Hui-Qian Luo Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Institute of high Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China School of Advanced Materials Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China Australian centre for Neutron Scattering Australian Nuclear Science and Technology OrganisationLucas Heights NSW-2232Australia ISIS Facility Rutherford Appleton LaboratoryChiltonDidcot Oxon OX110QXUnited Kingdom Songshan Lake Materials Laboratory Dongguan 523808China

We use neutron powder diffraction to investigate the magnetic and crystalline structure of Cr_(2)GaN.A magnetic phase transition is identified at T≈170 K,whereas no trace of structural transition is observed down to 6 *** Rietveld refinement with irreducible representations,the spin configuration of Cr ions in Cr_(2)GaN is depicted as an incommensurate sinusoidal modulated structure characterized by a propagating vector k=(0.365,0.365,0).Upon warming up to the paramagnetic state,the magnetic order parameter closely resembles to the temperature dependence of c-axis lattice parameter,suggesting strong magneto-elastic coupling in this ***,Cr_(2)Ga N provides a potential platform for exploration of magnetically tuned properties such as magnetoelectric,magnetostrictive and magnetocaloric effects,as well as their applications.

关键词： magnetic Elastic Coupling

Research on Nanofabrication Technology of Micro-/Nano-Stereo Rapid Prototyping of PCVD

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厦门大学学报（自然科学版） 2002年第S1期41卷 280-页

作者： Sandy TO Ultra-Precision Machining centre

At present, the most common micro/nano-scale fabri ca tion processes include the plane silicon process based on IC technology, stereo silicon process, LIGA, quasi-LIGA based on near ultra violet deep lithography, MEMS, energy beam etching and micro/nano-machining, etc. A common problem for t hese processes is the difficulty to fabricate arbitrary form for 3-dimensional micro/nano-parts, devices or mechanisms. To develop advanced MEMS manufacturin g technology, and to achieve fabrication of true 3-dimensional parts, devices or mechanisms, this paper proposes a nanofabrication technology for rapid proto typing of 3-dimensional parts, using plasma chemical vapor deposition (PCVD). This process can be describes as follows: A laser beam is produced by a low power, quasi molecule laser. It enters the vac uum chamber through a window, and is focused on with the substrate surface. A ga s in the chamber is ionized by the laser beam to produce PCVD on the substrate s urface, and forms a particle of the size of Ф100 nm (its thickness is about 100 nm). When the laser beam moves along X-axis, many particles form a line. Then the laser beam moves one step in Y-axis to form a new line. A plane is complete d by many lines. Then the substrate moves in Z-axis to form new plane. Eventu ally, many planes form a 3-dimensional component. Using available CAD/CAM softw are with this process, rapid prototyping of complex components can be achieved. A nanometer precision linear motor, such as that described in Chinese national p atent (patent No. ZL 98 2 16753.9), can be used to obtain the nanometer precisio n movements in the process. The process does not require mask, can be used for v arious rapid prototyping materials, to obtain high fabrication precision (its sc ale precision is 15 nm), and larger ratio of height to width of micro/nano-stru cture. It can find widespread applications in the fabrication of micro-mechani sm, trimming IC, and fabricating minilens, etc.

关键词： plasma nanofabrication rapid prototyping advan ced manufacturing technology micro/nano-technology

Bottom Simulating Reflector and Gas Seepage in Okinawa Trough:Evidence of Gas Hydrate in an Active Back-Arc Basin

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Journal of China University of Geosciences 2008年第2期19卷 152-161页

作者：栾锡武 Kelin Wang Roy Hyndman Eleanor Willoughby Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy of Sciences （IOCAS） Qingdao 266071 China Pacific Geoscience centre （PGC） Geological Survey of Canada Sidney V8L4B2 Canada

To look for gas hydrate, 22 multi-channel and 3 single-channel seismic lines on the East China Sea （ECS） shelf slope and at the bottom of the Okinawa Trough were examined. It was found that there was indeed bottom simulating reflector （BSR） occurrence, but it is very rare. Besides several BSRs, a gas seepage was also found. As shown by the data, both the BSR and gas seepage are all related with local geological structures, such as mud diapir, anticline, and fault-controlled graben-like structure. However, similar structural ＂anomalies＂ are quite common in the tectonically very active Okinawa Trough region, but very few of them have developed BSR or gas seepage. The article points out that the main reason is probably the low concentration of organic carbon of the sediment in this area. It was speculated that the rare occurrence of gas hydrates in this region is governed by structure-controlled fluid flow. Numerous faults and fractures form a network of high-permeability channels in the sediment and highly fractured igneous basement to allow fluid circulation and ventilation. Fluid flow in this tectonic environment is driven primarily by thermal buoyancy and takes place on a wide range of spatial scales. The fluid flow may play two roles to facilitate hydrate formation： to help gather enough methane into a small area and to modulate the thermal regime.

关键词： gas hydrate BSR gas seepage back-arc basin formation mechanism.

Deformation of the Zhangjiazhuang high-speed railway tunnel: an analysis of causal mechanisms using geomorphological surveys and D-InSAR monitoring

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Journal of Mountain Science 2021年第7期18卷 1920-1936页

作者： MENG Xing-min QI Tian-jun ZHAO Yan DIJKSTRA Tom SHI Wei LUO Yin-fei WU Yuan-zhao SU Xiao-jun ZHAO Fu-meng MA Jin-hui ZHANG Yi CHEN Guan YUE Dong-xia ZHANG Mao-sheng School of Earth Sciences Lanzhou UniversityLanzhou 730000China College of Earth and Environmental Sciences MOE Key Laboratory of Western China's Environmental SystemsLanzhou UniversityLanzhou 730000China Gansu Tech Innovation centre for Environmental Geology and Geohazard Prevention Lanzhou 730000China School of Architecture Building and Civil EngineeringLoughborough UniversityLoughboroughLE113TUUK Key Laboratory of Qinghai Environmental Geological Survey Xining 810007China Xi’an centre of China Geological Survey Xi’an 710054China

On 18 January 2016,the Zhangjiazhuang high-speed railway tunnel in Ledu,Qinghai Province,China,underwent serious deformation and structural damage.A crack formed at the top of the tunnel and the concrete on the crown peeled *** a result,the tunnel could not be operated for three *** order to determine the types and spatial distribution of the landslides in the region and the surface deformation characteristics associated with the tunnel deformation,we used field geological and geomorphological surveys,unmanned aerial vehicle image interpretation and differential interferometric synthetic aperture radar(D-In SAR) surface deformation *** ancient and old landslides were identified and analysed in the study *** deformation monitoring and investigation of buildings in several villages on the slope front showed that the tunnel deformation was not related to deep-seated gravitational slope ***,surface deformation monitoring revealed an active NEE–SWW fault in the area intersecting the tunnel at the location of the tunnel *** constitutes a plausible mechanism for the deformation of the *** study highlights the need for detailed engineering geomorphological investigations to better predict the occurrence of tunnel deformation events in the future.

关键词： Gaojiawan Landslide group Zhangjiazhuang tunnel Deformation Fault activity Irrigation infiltration

Heat sensitivity of eggs attributes to the reduction in Agasicles hygrophila population

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Insect Science 2020年第1期27卷 159-169页

作者： Dong Jia Xiao-Fang Yuan Yan-Hong Liu Chao-Qian Xu Yuan-Xin Wang Ling-Ling Gao Rui-Yan Ma College of Agriculture Shanxi Agricultural UniversityTaiguShanxiChina College o f Life Science Shanxi Agricultural UniversityTaiguShanxiChina CSIRO Agriculture and Food Centre for Environment and Life SciencesWembleyWestern AustraliaAustralia

Agasicles hygrophila has been introduced worldwide as a control agent for the invasive weed Alternanthera ***,global warming has potential impact on its controlling *** aim of this research was to explore the primary factors responsible for the greatly reduced *** population in hot *** imitate the temperature conditions in summers,different developmental stages of hygrophila were treated with high temperatures from 32.5℃ to 45℃ for 1-5 *** on the survival rate,the heat tolerance of each developmental stage was ranked from lowest to highest as follows:egg,1st,2nd,3rd instar larva,adult and *** showed the lowest heat tolerance with 37.5℃ as the critical temperature affecting larval *** treatment of the *** eggs at 37.5℃ for 1 h decreased the hatch rate to 24%.Our results indicated that when compared with the control at 25℃,1 h treatment at 37.5℃ prolonged the duration of the egg stage,shortened the duration of oviposition and total longevity,and changed the reproductive pattern of *** net reproductive rate,intrinsic rate and finite rate were all significantly *** results suggest that low heat tolerance of the eggs was the major factor responsible for the reduction of *** populations,and the key temperature was 37.5°***,appropriate measures should be taken to protect eggs in order to maintain the efficacy of *** in the biological control of *** in hot summers.

关键词： age-stage two-sex life table alligator weed flea beetle heat tolerance population dynamics

A Green Synthesis of Ru Modified g-C_(3)N_(4) Nanosheets for Enhanced Photocatalytic Ammonia Synthesis

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Energy Material Advances 2021年第1期2021卷 78-89页

作者： Derek Hao Jiawei Ren Ying Wang Hamidreza Arandiyan Magnus Garbrecht Xiaojuan Bai Ho Kyong Shon Wei Wei Bing-Jie Ni centre for Technology in Water and Wastewater(CTWW) School of Civil and Environmental EngineeringUniversity of Technology Sydney(UTS)SydneyNSW 2007Australia State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Laboratory of Advanced Catalysis for Sustainability School of ChemistryThe University of SydneySydney 2006Australia centre for Advanced Materials&Industrial Chemistry(CAMIC) School of ScienceRMIT UniversityMelbourneVIC 3000Australia Australian centre for Microscopy and Microanalysis The University of SydneySydney 2006Australia Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control Beijing University of Civil Engineering and ArchitectureBeijing 102612China

Nitrate is a crucial environmental pollutant,and its risk on ecosystem keeps *** conversion of nitrate to ammonia can simultaneously achieve the commercialization of environmental hazards and recovery of valuable ammonia,which is green and sustainable for the ***,due to the thermodynamic and kinetic energy barriers,photocatalytic nitrate reduction usually involves a higher selectivity of the formation of nitrogen that largely limits the ammonia synthesis *** this work,we reported a green and facile synthesis of novel metallic ruthenium particle modified graphitic carbon nitride *** with bulk graphitic carbon nitride,the optimal sample had 2.93-fold photocatalytic nitrate reduction to ammonia activity(2.627 mg/h/gcat),and the NH3 selectivity increased from 50.77%to 77.9%.According to the experimental and calculated results,the enhanced photocatalytic performance is attributed to the stronger light absorption,nitrate adsorption,and lower energy barrier for the generation of *** work may provide a facile way to prepare metal modified photocatalysts to achieve highly efficient nitrate reduction to ammonia.

关键词： ammonia nitrate selectivity