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Lithosphere architecture characterized by crust±mantle decoupling controls the formation of orogenic gold deposits

National science Review 2023年第3期10卷 77-91页

作者： Zengqian Hou Qingfei Wang Haijiang Zhang Bo Xu Nian Yu Rui Wang David I.Groves Yuanchuan Zheng Shoucheng Han Lei Gao Lin Yang Institute of Geology Chinese Academy of Geological Sciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Beijing) School of Earth and Space Sciences University of Science and Technology of China School of Electrical Engineering Chongqing University Centre for Exploration Targeting University of Western Australia

This study,via combined analysis of geophysical and geochemical data,reveals a lithospheric architecture characterized by crust-mantle decoupling and vertical heat-flow conduits that control orogenic gold mineralization in the Ailaoshan gold belt on the southeastern margin of *** mantle seismic tomography indicates that the crust-mantle decoupled deformation,defined from previous seismic anisotropy analysis,was formed by upwelling and lateral flow of the asthenosphere,driven by deep sub duction of the Indian continent,Our magnetotelluric and seismic images show both a vertical conductor across the Moho and high Vp/Vs anomalies both in the uppermost mantle and lowest crust,suggesting that crust-mantle decoupling promotes ponding of mantle-derived basic melts at the base of the crust via a heat-flow *** gas isotope and halogen ratios of gold-related ore minerals indicate a mantle source of ore fluid.A rapid decrease in Cl/F ratios of lamprophyres under conditions of 1.2 GPa and1050 ℃ suggests that the ore fluid was derived from degassing of the basic *** lithospheric architecture is recognized in other orogenic gold provinces,implying analogous formational controls.

关键词： crust–mantle decoupling lithosphere architecture orogenic gold deposit seismic tomography magnetotelluric imaging Tibet

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Failure analysis of Header Flange Cracking in Propane Dehydrogenation Unit 3

Failure Analysis of Header Flange Cracking in Propane Dehydr...

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2023 3rd International Conference on Frontiers of Electrical Power and Energy Systems, EPES 2023

作者： Lu, Xianjin Yu, Ting Chen, Yanbin Chen, Mao An, Zhicong Zhejiang Academy of Special Equipment Science Hangzhou310000 China Key Laboratory of Special Equipment Safety Testing Technology of Zhejiang Province Hangzhou310000 China Zhejiang Petrochemical Co. Ltd Zhoushan316000 China

The boiler fault of propane dehydrogenation unit is investigated by macroscopic inspections, mechanical properties testing, chemical composition analysis, metallographic microstructure, X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The experiments confirm the reason for cracks occurrence of SA182-F347H boiler that the stress corrosion cracking occurs. The sulfur injected into the device reacts with the flange metal to produce sulfide corrosion products. The improper control of flange manufacturing process and the operating temperature in the sensitized range lead to the sensitization of flange materials and reduce the corrosion resistance. During the equipment shutdown, the sulfide corrosion products on the surface of the flange reacted with air and water to form polysulfuric acid, and causing stress corrosion cracking and leakage of the sensitized F347H stainless steel flange. © Published under licence by IOP Publishing Ltd.

关键词： Microstructure

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Wavefront aberration evaluation of an off-axis two-mirror system through the optical-mechanical integration method based on dual quaternion 6

Wavefront aberration evaluation of an off-axis two-mirror sy...

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6th International Conference on Optoelectronic science and Materials, ICOSM 2024

作者： Li, Zhenchuang Qin, Tao Guo, Junli Cui, Zhangang Han, Peixian Jing, Zijian Yang, Xiaoli Qi, Bo Key Laboratory of Optical Engineering Chinese Academy of Sciences Chengdu China Institute of Optics and Electronics Chinese Academy of Sciences Chengdu China University of Chinese Academy of Sciences Beijing China University of Electronic Science and Technology of China Chengdu China

ISBN: (数字)9781510686823

ISBN: (纸本)9781510686816

Off-axis reflective systems have become one of the preferred solutions for space optical payloads because of their high energy efficiency and small point spread function ellipticity. However, restricted by structural asymmetry, off-axis mirrors' integrated assembly accuracy is always difficult. To achieve higher integrated precision during assembling, an optical-mechanical integration method based on dual quaternion (DQ) is proposed in this paper to evaluate the off-axis reflective system's wave aberration. Firstly, static analysis of the off-axis reflective optomechanical system is carried out before and after loading installation error respectively. Then, based on the DQ, the rigid body displacements (RBDs) of the off-axis mirrors are calculated to ensure the accurate extraction of the node displacement residual caused by the mirror deformation. Furthermore, the Zernike coefficients of the off-axis mirrors' surf, obtained through the vector height of the topological nodes, are used to estimate the system's wavefront change. Finally, compared with the integrated analysis software Sigfit, the reliability of the wave aberration evaluation obtained by the optical-mechanical integration method based on DQ is verified. Simulation and experimental results show that the optical-mechanical integration method based on DQ provides a more accurate reference for predicting the integrated assembly precision of the off-axis reflective optomechanical system. © 2024 SPIE.

关键词： Mirrors

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A New Fiber Detection Method for LAMOST Based on the Front-illuminated Method

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Research in Astronomy and Astrophysics 2022年第6期22卷 42-51页

作者： Ming Zhou Yong Zhang Guanru Lv Jian Li Zengxiang Zhou Zhigang Liu Jianping Wang Zhongrui Bai Yuan Tian Mengxin Wang Shuqing Wang Hongzhuan Hu Chao Zhai Jiaru Chu Zhijie Han Mingxu Liu Yiqiao Dong Hailong Yuan Yongheng Zhao Yaoquan Chu Haotong Zhang Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China University of Science and Technology of China Hefei 230026China

The double revolving fiber positioning technology is one of the key technologies for the success of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST).The accuracy of fiber positioning will directly affect the observation efficiency of *** achieve higher fiber positioning accuracy,the original open-loop controlled fiber positioning system urgently needs to be upgraded into a closed-loop control *** fiber detection is the most important part of the closed-loop controlled fiber positioning *** back-illuminated detection method is usually used to detect the fiber position by directly detecting the light spot generated at the fiber end in the multi-fiber spectral *** this paper,we introduce a new method to measure the fiber position based on the image of the front-illuminated LAMOST focal *** front-illuminated image does not require lighting devices inside the spectrograph,and it could reduce the instability and light pollution in the spectrograph *** method measures the fiber position by fitting the profile of the fiber pinhole with a 2D Gaussian function.A series of tests show that the relative position measurement precision of the front-illuminated method is about 012,and the method could have the same accuracy as the back-illuminated method once the system bias is calibrated by a simple radial correction *** required fiber positioning accuracy of LAMOST is 04,and the new method satisfies the requirement of LAMOST fiber detection accuracy and could be used in the closed-loop fiber control system.

关键词： techniques image processing-methods data analysis-instrumentation detectors

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Investigation on E-Band Hybrid-Serpentine slow-wave circuit 24

Investigation on E-Band Hybrid-Serpentine slow-wave circuit

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24th International Vacuum Electronics Conference, IVEC 2023

作者： Li, Fei Xiao, Liu Zhao, Jiandong Wang, Zicheng Yi, Hongxia Shang, Xinwen Sun, Yuhui Aerospace Information Research Institute Key Laboratory of Science and Technology on High Power Microwave Sources and Technologies Chinese Academy of Sciences Beijing100190 China

ISBN: (纸本)9781665473217

A new E-band hybrid-serpentine slow-wave circuit is investigated by theoretical analysis and numerical simulation. The results show that the hybrid-serpentine slow-wave circuit achieves higher coupling impedance than basic serpentine circuit with greater design flexibility. By allowing the vertical distances between the upper and lower centers of bend curvature for both the inner and outer bends to be different, this hybrid-serpentine circuit gains an additional degree of freedom that can be used to widen or narrow the stopband and to tailor the dispersion near the 2π point to avoid backward wave oscillations (BWO). These results predicted that the E-band traveling wave tube(TWT) with hybrid-serpentine slow-wave circuit will achieve a better performance, including high-electron efficiency, high gain and good stability. © 2023 IEEE.

关键词： Efficiency

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An integrative analysis of hydroclimatic elements in the three-river source region for historical and future periods:Shift toward an intensified hydrological cycle

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国际水土保持研究（英文） 2025年第1期13卷 43-66页

作者： Rashid Mahmood Shaofeng Jia Aifeng Lv Mukand S.Babel Key Laboratory of Water Cycle and Related Land Surface Processes/Institute of Geographic Science and Natural Resources Research Chinese Academy of SciencesBeijingChina Key Laboratory of Water Cycle and Related Land Surface Processes/Institute of Geographic Science and Natural Resources Research Chinese Academy of SciencesBeijingChina Qinghai Key Laboratory of Basin Water cycle and ecology Qinghai Institute of Water Resources and HydropowerXiningChina School of Geographical Sciences Qinghai Normal UniversityXiningChina Water Engineering and Management Asian Institute of TechnologyPathumthaniThailand

The Three-River Source Region(TRSR),China's water tower and an important ecological barrier in China,provides a considerable amount of water to the downstream regions,home to more than 500 million *** present study focused on the assessment of hydrological components(i.e.,precipitation,actual evapotranspiration,potential evapotranspiration,surface flow,baseflow,streamflow,soil mois-ture,snowmelt water,and terrestrial water storage),their transformation and trends along with mete-orological elements(i.e.,maximum temperature,minimum temperature,mean temperature,relative humidity,wind speed,and sunshine hours)in the historical and future *** this,the hydrological model,HEC-HMS,was applied to simulate hydrological components and Mann-Kendal to explore the trends for *** time,the statistical downscaling model,SDSM,was used to generate climatic data under the shared socio-economic scenario-5(SSP585)in the region,which was applied to simulate the hydrological *** assessment results showed that precipitation transformed into evapotrans-piration and streamflow by 70％and 30％,*** the region,streamflow was generated by 78％,22％,and 5.6％by baseflow,surface flow,and snowmelt According to trend results,all climatic variables showed statistically significant trends but insignificant in all hydrological components for the historical period,except ***,all hydroclimatic components were projected to increase in the future,except *** example,temperature,precipitation,evapotranspiration,streamflow,and direct flow(surface flow)will increase by 1.4(3.3)℃,12(36)％,8.5(19)％,25(95)％,and 77(473)％in 2021-2060(2061-2100)relative to 1981-2020,which shows,the region will be hotter and wetter,with high flooding potential in the *** results will be helpful for precise water resources planning and management in this extremely sensitive region to climate change.

关键词： Climate change Water resources assessment Hydrological cycle Hydrological Modeling Three-River Source Region

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analysis of the strength property of capillary plasma generator 3

Analysis of the strength property of capillary plasma genera...

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3rd International Conference on Defence technology, ICDT 2022

作者： Li, Haiyuan Li, Baoming National Key Laboratory of Transient Physics Nanjing University of Science and Technology Jiangsu Nanjing210094 China China Academy of Ordnance Beijing100089 China

Plasma generator is a key component of electrothermal chemical gun. Its function is to produce plasma under the action of high pulse current and enhance the combustion characteristics of the propellant, thus improving the launch efficiency and muzzle velocity. The structural properties of the plasma generator are related to its discharge characteristics, internal pressure, and plasma jet characteristics, etc. This paper studies the strength property of capillary plasma generator under working conditions, and provides a reference for the structural design of the plasma generator. © Published under licence by IOP Publishing Ltd.

关键词： Plasma jets

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A bibliographic study reviewing the last decade of hydrochar in environmental application:history,status quo,and trending research paths

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Biochar 2023年第1期5卷 231-257页

作者： Junxia Huang Yanfang Feng Huifang Xie Ping Wu Minli Wang Bingyu Wang Qiang Zhang Shicheng Zhang Zhengang Liu Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Agro-Environment in Downstream of Yangtze Plain Ministry of Agriculture and Rural AffairsInstitute of Agricultural Resources and EnvironmentJiangsu Academy of Agricultural SciencesNanjing 210014China Centre for Agricultural Resources Research Institute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Faculty of Civil Engineering and Mechanics Kunming University of Science and TechnologyKunming 650500China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Hydrothermal carbonization(HTC)technology has increasingly been considered for biomass conversion applications because of its economic and environmental *** an HTC conversion product,hydrochar has been widely used in the agricultural and environmental fields for decades.A CiteSpace-based system analysis was used for conducting a bibliometric study to understand the state of hydrochar environmental application research from 2011 to *** had a basic understanding of hydrochar between 2011 and 2016 when they discovered hydrochar could apply to agricultural and environmental improvement *** clustering results of the literature published in 2017-2021 showed that soil quality and plant growth were the major research topics,followed by carbon capture and greenhouse gas emissions,organic pollutant removal,and heavy metal adsorption and its *** review also pointed out the challenge and perspective for hydrochar research and application,namely:(1)the environmental effects of hydrochar on soils need to be clarified in terms of the scope and conditions;(2)the influence of soil microorganisms needs to be investigated to illustrate the impact of hydrochar on greenhouse gas emissions;(3)combined heavy metal and organic contaminant sorption experiments for hydrochar need to be conducted for large-scale applications;(4)more research needs to be conducted to reveal the economic benefits of hydrochar and the coupling of hydrochar with anaerobic digestion *** review suggested that it would be valuable to create a database that contains detailed information on how hydrochar got from different sources,and different preparation conditions can be applied in the environmental field.

关键词： Hydrochar Environmental applications Research hotspots Bibliometrics CiteSpace

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Physical-chemical and biological control of the zooplankton community in the Amundsen Sea, Antarctica

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Advances in Polar science 2023年第1期34卷 17-27页

作者： CHEN He LI Haibo ZHAO Jun LI Dong WAN Jun YANG Guang College of Environmental and Safety Engineering Qingdao University of Science and Technology266061 QingdaoChina Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMNRHangzhou 310012China University of Chinese Academy of Sciences Beijing 100049China

Zooplankton are critical components of the Southern Ocean ecosystems,acting as trophic links between phytoplankton and higher-level *** composition,abundance,carbon biomass,and community structure of zooplankton were studied based on samples collected with a Norpac net(330-μm mesh,0.5-m^(2) net mouth)during the austral summers of 2017/*** communities in a latitudinal gradient were identified based on both a zooplankton abundance dataset and a biomass *** were mainly dominated by small copepods(e.g.,Oithona similis and Ctenocalanus citer)in terms of abundance,while the total zooplankton biomass was dominated by krill(Euphausia superba and Thysanoessa macrura)and large copepods(e.g.,Calanoides acutus,Calanus propinquus,and Metridia gerlachei).Redundancy analysis demonstrated that environmental factors(e.g.,temperature,nitrate,dissolved oxygen,ammonium)accounted for more than 40%of the variance in zooplankton abundance/*** indicates that physical processes significantly affect the zooplankton ***,a significant positive correlation was found between the abundance/biomass of zooplankton and that of dominant phytoplankton and ciliates,which suggests trophic links among various plankton functional *** results reveal that both physical processes and biological factors shape the community structure of zooplankton in the Amundsen Sea.

关键词： zooplankton community abundance biomass Amundsen Sea Southern Ocean

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Cross-shelf variation of internal tides west of the Dongsha Plateau in the northern South China Sea

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Acta Oceanologica Sinica 2023年第10期42卷 23-35页

作者： Wei Yang Ruixiang Li Yanqing Feng Huijie Xue State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 100049China South China Sea Marine Survey Center Ministry of Natural ResourcesGuangzhou 510300China Key Laboratory of Marine Environment Survey Technology and Application Ministry of Natural ResourcesGuangzhou 510300China State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China

We examine the cross-shelf variation of internal tides(ITs)west of the Dongsha Plateau in the northern South China Sea based on observations from 4 moorings deployed between August 2017 and September *** the slope,the amplitude of diurnal baroclinic current ellipses are 5 times larger than that of barotropic *** baroclinic energy quickly dissipates during cross-shelf propagation,and barotropic currents become dominant on the shelf outside of the Zhujiang River Estuary,with the amplitude of semidiurnal barotropic current ellipses being 10 times larger than that of the baroclinic *** modal decomposition indicates the first baroclinic mode is dominant for both diurnal and semidiurnal *** total horizontal kinetic energy(HKE)of the first three baroclinic modes shows spatiotemporal differences among the 4 *** the slope,the HKE for diurnal ITs is stronger in summer and winter,but weaker in spring and autumn;for semidiurnal ITs there is a similar seasonal variation,but the HKE in winter is even stronger than that in *** the shallow shelf,both diurnal and semidiurnal ITs maintain a certain intensity in summer but almost disappear in *** analysis shows that only the upper water column is affected by seasonal variation of stratification on the slope,variation of diurnal ITs is thus controlled by the semi-annual cycle of barotropic energy input from the Luzon Strait,while the incoherent baroclinic currents make a major contribution to the temporal variation of semidiurnal *** the shelf region,the water column is well mixed in winter,and the baroclinic energy largely dissipates when ITs propagate to the shelf zone despite of a strong barotropic energy input from the Luzon Strait.

关键词： internal tide Dongsha Plateau cross-shelf variation dynamic modal decomposition coherent

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