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The coupling control of biological precursors and environmental factors onβ-carotane enrichment in alkaline lacustrine source rocks:A case study from the Fengcheng formation in the western Junggar Basin,NW China

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Petroleum Science 2024年第2期21卷 836-854页

作者： Mao-Guo Hou Ming Zha Hua Liu Hai-Lei Liu Jiang-Xiu Qu Ablimit Imin Xiu-Jian Ding Zhong-Fa Jiang School of Geosciences China University of PetroleumQingdaoShandong266580China Research Institute of Exploration and development Xinjiang Petroleum Administration BureauKaramayXinjiang834000China

The organic-rich mudstones and dolostones of the Permian Fengcheng Formation(Fm.)are typically alkaline lacustrine source rocks,which are typified by impressively abundantβ-*** β-carotane has been well acknowledged as an effective indicator of biological sources or depositional ***,the specific biological sources of β-carotane and the coupling control of biological sources and environmental factors on the enrichment of β-carotane in the Fengcheng *** *** on a comprehensive investigation of the bulk,molecular geochemistry,and organic petrology of sedimentary rocks and the biochemistry of phytoplankton in modern alkaline lakes,we proposed a new understanding of the biological precursors of β-carotane and elucidated the enrichment mechanism of β-carotane in the Fengcheng *** results show that the biological precursors crucially control the enrichment of β-carotane in the Fengcheng *** haloalkaliphilic cyanobacteria are the primary biological sources of β-carotane,which is suggested by a good positive correlation between the 2-methylhopane index,7-+8-methyl heptadecanes/C_(max),C_(29%),and β-carotane/C_(max)in sedimentary rocks and the predominance of cyanobacteria with abundantβ-carotene in modern alkaline *** enrichment of β-carotane requires the reducing condition,and the paleoredox state that affects the enrichment of β-carotane appears to have a *** paleoclimate conditions do not considerably impact the enrichment of β-carotane,but they have some influence on the water's paleosalinity by affecting evaporation and *** it does not directly affect the enrichment of β-carotane in the Fengcheng Fm.,paleosalinity does have an impact on the cyanobacterial precursor supply and the preservation conditions.

关键词： β-carotane enrichment Cyanobacterial input Environmental impact Alkaline lacustrine source rocks The Fengcheng formation

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Source Enrichment Control on the Scale of Magmatic-Hydrothermal W-Sn Mineralization:Insights from Triassic and Jurassic Magma Reservoirs in the Continental Crust,Xitian,South China

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 132-149页

作者： GUO Chunli Simon AWILDE Coralie SIEGEL CHEN Zhenyu WU Shichong MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China SinoProbe Laboratory Chinese Academy of Geological SciencesBeijing 100094China School of Earth and Planetary Sciences Curtin UniversityPerth 6845Australia Discovery program Mineral ResourcesCommonwealth Scientific and Industrial Research OrganisationAustralian Resources Research CentrePerth 6151Australia No.416 Geological Group Hunan Bureau of Mineral Exploration and DevelopmentZhuzhouHunan 412007China

There are two factors,source composition and magmatic differentiation,potentially controlling W-Sn *** one is more important is widely debated and may need to be determined for each individual *** Xitian granite batholith located in South China is a natural laboratory for investigating the above *** consists essentially of two separate components,formed in the Triassic at ca.226 Ma and Jurassic at ca.152 Ma,*** Triassic and Jurassic rocks are both composed of porphyritic and fine-grained *** latter resulted from highlydifferentiated porphyritic ones but they have similar textural characteristics and mineral assemblages,indicating that they reached a similar degree of crystal *** both fine-grained phases are highly differentiated with elevated rare metal contents,economic W–Sn mineralization is rare in the Triassic granitoids and this can be attributed to less fertile source materials than their Jurassic counterparts,with a slightly more enriched isotopic signature and whole-rockεNd(226 Ma)of−10.4 to−9.2(2σ=0.2)compared withεNd(152 Ma)of−9.2 to−8.2(2σ=0.2)for the Jurassic *** initial W-Sn enrichment was derived from the metasedimentary rocks and strongly enhanced by reworking of the continental crust,culminating in the Jurassic.

关键词： W-Sn mineralization magma reservoir geometry crystal fractionation Xitian Triassic-Jurassic granitic batholith Nanling Range South China

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Risk Assessment of Deep-Water Horizontal X-Tree Installation

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China Ocean Engineering 2024年第2期38卷 210-220页

作者： MENG Wen-bo FU Guang-ming HUANG Yi LIU Shu-jie HUANG Liang GAOYong-hai CNOOC China Limited Zhanjiang BranchZhanjiang 524057China Key Laboratory of Unconventional Oil and Gas development Ministry of Education(China University of Petroleum(East China))Qingdao 266580China

Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation,to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees,this paper established a modular risk evaluation model based on a fuzzy fault ***,through the analysis of the main process oftree down and combining the Offshore&Onshore Reliability Data(OREDA)failure statistics and the operation procedure and the data provided by the job,the fault tree model of risk analysis of the tree down installation was ***,by introducing the natural language of expert comprehensive evaluation and combining fuzzy principles,quantitative analysis was carried out,and the fuzzy number was used to calculate the failure probability of a basic event and the occurrence probability of a top ***,through a sensitivity analysis of basic events,the basic events of top events significantly affected were determined,and risk control and prevention measures for the corresponding high-risk factors were proposed for subsea horizontal X-tree down installation.

关键词： subsea horizontal X-tree risk assessment fuzzy fault tree modular risk evaluation model

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Dust particle surface potential in an argonhelium plasma using the(r,q)-distribution function

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Communications in Theoretical Physics 2024年第9期76卷 143-150页

作者： Bahaaudin M Raffah A A Abid Abdullah Khan Amin Esmaeili Yas Al-Hadeethi M N S Qureshi Department of Physics Faculty of Sciences King Abdulaziz University Lithography in Devices Fabrication and development Research Group Deanship of Scientific ResearchKing Abdulaziz University Joint Laboratory of Plasma Application Technology Institute of Advanced Technology University of Science and Technology of China CAS Key Laboratory of Geospace Environment University of Science and Technology of China Department of Physics Zhejiang Normal University Department of Physics Graduate School of Science Tokyo Metropolitan University Department of Physics GC University

In this paper, the dust particle surface potential for argon-helium plasma is evaluated analytically and numerically in the context of negatively charged dust particles by employing a power-law(r, q)-distribution function. Recent studies have reported the argon-helium plasma and conducted a brief theoretical and experimental survey. To deepen our understanding further, this study aims to analyze the argon-helium plasma comprehensively using the same pattern but with the(r, q)-distribution function. For this purpose, the current balance equations are derived for electron, helium and argon ions, when these charge species attain the quasineutrality *** numerically examined the currents of plasma species for a broad range of effective distribution function parameters r and q. It is revealed that the surface potential of dust particles is significantly affected by the parameters r and q, helium ion-to-electron temperature ratio,argon ion-to-electron temperature ratio, and helium ion to argon ion number density ratio. By incorporating the multi-ion(argon-helium) species, the significance of low-temperature nonMaxwellian dusty(complex) plasma is briefly examined.

关键词： dust charge potential dusty plasma helium argon plasma non-Maxwellian distribution plasma physics q distribution function r

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Bureaucratic Culture and Innovation

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China & World Economy 2024年第3期32卷 31-66页

作者： Shigang Li Kexin She Li Zhang International School of Business and Finance Sun Yat-sen UniversityChina National School of development Peking UniversityChina International School of Business and Finance Key Laboratory of Mesoeconomics and Coordinated Development of Regions and IndustriesSun Yat-sen UniversityChina

This study explores the effects of bureaucratic culture on *** define bureaucratic culture as a culture in which power and officials are held in the highest *** panel data of publicly listed Chinese manufacturing firms from 2007 to 2015,we found that bureaucratic culture negatively correlated with firms'patent output.A mechanism analysis shows that bureaucratic culture hindered corporate innovation by reducing firms'research and development inputs and decreasing innovation ***,we provided evidence that anti-corruption campaigns and the development of formal institutions could neutralize the negative impact of bureaucratic culture on corporate *** study is the first to investigate quantitatively the causal effect of bureaucratic culture on corporate innovation and it can deepen the understanding of the relationship between culture and innovation in *** speculate that promoting a creative culture,particularly one that fosters entrepreneurial spirit,is of utmost importance.

关键词： bureaucratic culture corporate innovation economic growth talent allocation

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Positive Effect of Transcranial Direct Current Stimulation on Visual Verbal Working Memory in Patients with Attention-Deficit/Hyperactivity Disorder

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Open Journal of Psychiatry 2024年第4期14卷 334-346页

作者： Tomoko Uchida Daisuke Matsuzawa Tadashi Shiohama Katsunori Fujii Akihiro Shiina Masamitsu Naka Katsuo Sugita Eiji Shimizu Naoki Shimojo Hiromichi Hamada Department of Pediatrics Graduate School of Medicine Chiba University Chiba Japan Research Center for Child Mental development Chiba University Chiba Japan Division of Medical Care and Treatment Center for Forensic Mental Health Chiba University Chiba Japan Department of Cognitive Behavioral Physiology Graduate School of Medicine Chiba University Chiba Japan

Background: Working memory is an executive function that plays an important role in many aspects of daily life, and its impairment in patients with attention-deficit/hyperactivity disorder (ADHD) affects quality of life. The dorsolateral prefrontal cortex (DLPFC) has been a good target site for transcranial direct current stimulation (tDCS) due to its intense involvement in working memory. In our 2018 study, tDCS improved visual-verbal working memory in healthy subjects. Objective: This study examines the effects of tDCS on ADHD patients, particularly on verbal working memory. Methods: We conducted an experiment involving verbal working memory of two modalities, visual and auditory, and a sustained attention task that could affect working memory in 9 ADHD patients. Active or sham tDCS was applied to the left DLPFC in a single-blind crossover design. Results: tDCS significantly improved the accuracy of visual-verbal working memory. In contrast, tDCS did not affect auditory-verbal working memory and sustained attention. Conclusion: tDCS to the left DLPFC improved visual-verbal working memory in ADHD patients, with important implications for potential ADHD treatments.

关键词： Working Memory Attention-Deficit/Hyperactivity Disorder Dorsolateral Prefrontal Cortex Transcranial Direct Current Stimulation

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Environmental arsenic(As)and its potential relationship with endemic disease in southwestern China

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Journal of Environmental Sciences 2024年第5期139卷 46-59页

作者： Donglin Li Hucai Zhang Fengqin Chang Lizeng Duan Yang Zhang Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan UniversityKunming 650500China Southwest United graduate School Kunming 650500China

Many cases of an unknown disease exhibiting the clinical features of limb gangrene,blisters,ulceration,and exfoliation have been reported in Daping village(DV)in southwestern ***,the pathogenesis is unknown and has puzzled doctors for many years.A preliminary study on heavy metals and symptoms indicated that arsenic might pose the greatest threat to the health of local ***,to explore the sources of and factors influencing arsenic enrichment in DV,whose residents exhibit signs of arsenic poisoning,the As contents in soil,water,and plants were systematically *** results indicated high As contents in plant and soil samples obtained from the area,and the source of As may be linked to the weathering of black shale *** of soil and consumption of plants were the two main As exposure pathways among children and adults,respectively,and children exhibited a higher health risk than *** presume and emphasize that when extreme drought events occur,humans might face unusual risks resulting from exposure to toxic elements and the direct consumption of highly polluted *** study provides a new perspective and sheds light on the environmental geochemistry and health links of this disease.

关键词： Endemic disease Arsenic(As) Risk assessment Black shale Climate change

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Optimal Time-of-use Pricing for Renewable Energy-powered Microgrids: A Multi-agent Evolutionary Game Theory-based Approach

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 162-174页

作者： Yu Zeng Yinliang Xu Xinwei Shen Hongbin Sun Tsinghua-Berkeley Shenzhen Institute.Tsinghua Shenzhen International graduate School Tsinghua UniversityShenzhen 518055China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China

While price schedules can help improve the economic efficiency of renewable energy-powered microgrids,timeof-use(TOU)pricing has been identified as an effective way for microgrid development,which is presently limited by its high *** this study,we propose an evolutionary game theoretic model to explore optimal TOU pricing for development of renewable energy-powered microgrids by applying a multi-agent system,that comprises a government agent,local utility company agent,and different types of consumer *** the proposed model,we design objective functions for the company and the consumers and obtain a Nash equilibrium using backward *** pricing strategies,namely,the TOU seasonal pricing and TOU monthly pricing,are evaluated and compared with traditional fixed *** numerical results demonstrate that TOU schedules have significant potential for development of renewable energy-powered microgrids and are recommended for an electric company to replace traditional fixed ***,TOU monthly pricing is more suitable than TOU seasonal pricing for microgrid development.

关键词： Game theory microgrid multi-agent system renewable energy time-of-use pricing

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Flashover Characteristics of Dry Band-water band on Hydrophobic Surfaces

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 392-400页

作者： Xiaohan Wu Fanghui Yin Bin Cao Daiming Yang Shichao Shao Liming Wang Tsinghua-Berkeley Shenzhen Institute(TBSI) Shenzhen 518055China Shenzhen International graduate School Tsinghua UniversityShenzhen 518055China Shenzhen Polytechnic School Shenzhen 518055China

Due to their outstanding anti-flashover characteristics,composite insulators have been extensively applied in power systems.A lot of research has investigated flashover characteristics of hydrophobic specimens with artificial water ***,the phenomenon is not consistent with that of the contaminated composite *** the test specimens covered with water droplets,there is no obvious leakage current before the flashover and no obvious relationship between flashover voltage and the conductivity of water *** the contaminated composite insulator surface,there are short continuous arcs on the insulators before critical flashover,making insulators look like a luminous *** that under these two conditions,the proportion of water along the insulation distance is different,the flashover characteristic of“dry band-water band”on a hydrophobicity surface is analyzed in the present *** influence of the water band parameter(including length,width,and conductivity)as well as the length of dry band is *** this basis,the arc generation and development process of the surface covered with“dry band-water band”is *** research results improve the understanding of the flashover process on contaminated composite insulators.

关键词： Flashover characteristics hydrophobicity partial arc water band

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Sequential enantioselective Ugi-4CR/post-Ugi transformation strategy:a precise construction of structurally diverse azaspiro polycyclic scaffolds

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Science China Chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu Jun-Xiu Shi Yi-Ming Ou Hua-Jie Jiang Yi-Jun Fang Qi-Ming Wang Quan Gao Jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

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