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Experimental and numerical simulation study on the erosion behavior of the elbow of gathering pipeline in shale gas field

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Petroleum Sc.ence 2024年第2期21卷 1257-1274页

作者： en-Bin Liu Shen Huang ding-chao Tian Lai-Min Shi Shan-Bi Peng He Zheng Petroleum engineering School Southwest Petroleum UniversityChengdu 610500SichuanChina chongqing Natural Gas Sales center Natural Gas BranchSinopecChongqing400023China Zhejiang Zheneng Natural Gas Operation co. Ltd.Hangzhou 310000ZhejiangChina School of civil engineering and Architecture Southwest Petroleum UniversityChengdu 610500SichuanChina Louisiana Tech Univ Trenchless Technol Ctr599 Dan Reneau DrRustonLA71270USA Southwest Oil and Gas Field Branch Natural Gas Research Institute Chengdu 610213SichuanChina

During the production period of shale gas, proppant particles and rock debris are produced together,which will seriously erode the elbows of gathering pipelines. In response to this problem, this paper takes the elbow of the gathering pipeline in the changning Shale Gas Field as an example to test the erosion rate and material removal mechanism of the test piece at different angles of the elbow through experiments and compares the four erosion models with the experimental results. Through analysis, it is found that the best prediction model for quartz sand-carbon steel erosion is the Oka model. Based on the Oka model, FLUenT software was used to simulate and analyze the law of erosion of the elbow of the gas gathering pipeline under different gas flow velocities, gas gathering pressure, particle size, length of L1,and bending directions of the elbow. And a spiral pipeline structure is proposed to reduce the erosion rate of the elbow under the same working conditions. The results show that this structure can reduce erosion by 34%.

关键词： Shale gas Gas gathering pipeline Elbow Erosion cFD

Inter-agency government information sharing under data-driven blockchain framework

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控制理论与应用 2024年第8期41卷 1369-1376页

作者： XIAO Jiong-en hong Ming ding Li-ping International Business School Guangdong University of Finance and EconomicsGuangzhou Guangdong 510320China Department of Electronic Business South China University of TechnologyGuangzhou Guangdong 510641China Institute of Software Chinese Academy of SciencesBeijing 100190China Guangzhou Institute of Software Application Technology Electronic Forensics LaboratoryGuangzhou Guangdong 511400China

The inter-agency government information sharing(IAGIS)plays an important role in improving service and effic.ency of government ***,there is still no effective and secure way for data-driven IAGIS to fulfill dynamic demands of information sharing between government *** by blockchain and data mining,a data-driven framework is proposed for IAGIS in this ***,the blockchain is used as the core to design the whole framework for monitoring and preventing leakage and abuse of government information,in order to guarantee information ***,a four-layer architecture is designed for implementing the proposed ***,the classical data mining algorithms PageRank and Apriori are applied to dynamically design smart contracts for information sharing,for the purposed of flexibly adjusting the information sharing strategies according to the practical demands of government agencies for public management and public ***,a case study is presented to illustrate the operation of the proposed framework.

关键词： government data processing blockchain PageRank apriori

Downregulation of Serum PTen Expression in Mercury-Exposed Population and PI3K/AKT Pathway-Induced Inflammation

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Biomedical and environmental Sc.ences 2024年第4期37卷 354-366页

作者： MEI Peng ding en Min YIN Hao Yang ding Xue Xue WANG Huan WANG Jian Feng HAN Lei ZHANG Heng Dong ZHU Bao Li School of Public Health Nanjing Medical UniversityNanjing 210000JiangsuChina Institute of Occupational Disease Prevention Jiangsu Province Center for Disease Prevention and ControlNanjing 21000JiangsuChina Suzhou center for Disease Prevention and control Suzhou 215004JiangsuChina center for Global Health School of Public HealthNanjing Medical UniversityNanjing 210000JiangsuChina

Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological *** Differentially expressed genes related to Hg exposure were identified and validated using gene expression microarray analysis and extended validation. Hg-exposed cell models and PTen lowexpression models were established in vitro using 293T cells. PTen gene expression was assessed using qRT-PcR, and Western blotting was used to measure PTen, AKT, and PI3K protein levels. IL-6 expression was determined by *** combined findings from gene expression microarray analysis, bioinformatics, and population expansion validation indicated significant downregulation of the PTen gene in the high-concentration Hg exposure group. In the Hg-exposed cell model(25 and 10 μmol/L), a significant decrease in PTen expression was observed, accompanied by a significant increase in PI3K, AKT, and IL-6 ***, a low-expression cell model demonstrated that PTen gene knockdown led to a significant decrease in PTen protein expression and a substantial increase in PI3K, AKT, and IL-6 *** This is the first study to report that Hg exposure downregulates the PTen gene, activates the PI3K/AKT regulatory pathway, and increases the expression of inflammatory factors, ultimately resulting in kidney inflammation.

关键词： PTen Occupational mercury exposure Occupational health PI3K/AKT pathway 293T cell IL-6

Experimental Study on Towing characteristics of composite Bucket Wellhead Platform

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china Ocean engineering 2024年第3期38卷 531-542页

作者： ZHANG Pu-yang LIU Ying-fei LE cong-huan ding hong-yan BAI Yu State Key Laboratory of Hydraulic.engineering Intelligent construction and Operation Tianjin UniversityTianjin 300072China

With the rapid development of large-scale development of marginal oilfields in china,simple wellhead platforms that are simple in structure and easy to install have become an inevitable choice in the process of oilfield ***,traditional simple wellhead platforms are often discarded after a single *** pursuit of a more costeffective approach to developing marginal oilfields,this paper proposes a new offshore oil field development facility—an integrated bucket foundation for wellhead *** verify the safety of its towing behavior and obtain the dynamic response characteristics of the structure,this paper takes a bucket integrated bucket foundation for wellhead platform with a diameter of 40 m as the research *** combining physical model tests and numerical simulations,it analyzes the static stability and dynamic response characteristics of the structure during towing,complete with the effects of the draft,wave height,wave period,and towing point height,which produce the dynamic responses of the structure under different influence factors,such as roll angle,pitch angle,heave acceleration and towing force as well as the sensibility to transport *** results show that the integrated bucket foundation for wellhead platform is capable of self-floating towing,and its movement is affected by the local environment,which will provide a reference for actual projects.

关键词： composite bucket foundation wellhead platform air flotation towing model test

Social network learning effic.ency in the principal-agent relationship

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Journal of Management Sc.ence and engineering 2024年第2期9卷 193-219页

作者： chuan ding Yilin hong Yang Li Peng Liu School of Mathematics Southwestern University of Finance and EconomicsChengdu611130China S.c.Johnson college of Business Cornell UniversityIthacaNY14853USA

Under the bounded rationality assumption,a principal rarely provides an optimal contract to an *** from others is one way to improve such a *** paper studies the effic.ency of social network learning(SNL)in the principal–agent *** first introduce the cobb-Douglas production function into the classic Holmstrom and Milgrom(1987)model with a constant relative risk-averse agent and work out the theoretically optimal *** are then designed to model the SNL process based on profit gaps between contracts in a network of *** the uncertainty of the agent's labor output,we find that the principals can reach a consensus that tends to result in overcompensation compared to the optimal ***,this study examines how network attributes and model parameters impact learning effic.ency and posits several summative *** simulation results validate these hypotheses,and we discuss the relevant economic implications of the observed changes in SNL effic.ency.

关键词： Simulation Social network learning Principaleagent Reaching consensus Learning effic.ency

Modification of Bcc phase and the enhanced reversible hydrogen storage properties of Ti-V-Fe-Mn alloys with varied V/Fe ratios

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china Foundry 2024年第5期21卷 546-554页

作者： Xiang-feng Ma Xin ding en-lai Liu Rui-run c.en Xin-xiu Wang Yong Zhang and Jing-jie Guo National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China School of Materials Sc.ence and engineering Shandong University of Science and TechnologyQingdao 266500ShandongChina AEcc Harbin Dongan Engine Co.Ltd.Harbin 150001China

Ti-V-based alloys are proved of huge potential in storing hydrogen,but the incomplete reversible hydrogen storage capacity caused by overstability of V hydride has limited the large-scale *** this study,Ti_(32)V_(40+x)Fe_(23-x)Mn_(5)(x=0,4,8,12,at.%)alloys were designed,and the effects of V/Fe ratio on phase constitution and hydrogen storage properties were *** main phase of the alloys is body-centered cubic(Bcc)phase,and the lattice constants of the Bcc phase decrease with the decrease of V/Fe ***,c14 Laves phase exists in alloys with a Fe content of 19at.%to 23at.%.For hydrogenation,the c14 Laves phase can accelerate the hydrogen absorption rate,but the hydrogen absorption capacity is *** the decrease of V/Fe ratio,the hydride gradually *** to its large lattice constant and high hydrogen absorption phase content,the Ti_(32)V_(52)Fe_(11)Mn_(5)alloy shows the most enhanced hydrogen storage properties with hydrogenation and dehydrogenation capacities of 3.588wt.%at 298 K and 1.688wt.%at 343 K,*** hydrogen absorption capacity of this alloy can be reserved to 3.574wt.%after 20 cycles of hydrogen absorption and desorption.

关键词： hydrogen storage Ti-based alloy lattice constant Bcc phase

Induced Absolute configuration of Achiral Tetradentate Ligands in Metal–Organic Frameworks for circularly Polarized Luminescence

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chinese Journal of chemistry 2024年第11期42卷 1260-1266页

作者： hong-Ru Fu Dan-Dan Ren Kun Zhang hong c.en Xiaoyan Lu Qing-Rong ding Lu-Fang Ma college of chemistry and chemical engineering Luoyang Normal UniversityLuoyangHenan471934 China college of Materials&chemical engineering China Three Gorges UniversityYichangHubei443002 China State Key Laboratory of Structural chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian350002 China

The crystallization of chiral molecules is of great significance to understand the origin and evolution of hierarchical chirality and reveal the relationships between structural chirality and circularly polarized luminescence(cPL)***,we report two pairs of chiral metal–organic frameworks(MOFs)(DcF-17/LcF-17,DcF-18/LcF-18)by utilizing tetradentate ligands tetra(3-imidazoylphenyl)ethylene(TIPE)and 4,4'-[4',5'-bis[4-(4-pyridinyl)phenyl][1,1':2',1”-terphenyl]-4,4”-diyl]bis[pyridine](TPPP)as *** can be observed that the spontaneous resolution of the achiral ligands is converted into the induced resolution,and the ligands form the absolute configuration by using enantiopure camphoric acid(cam)as chiral induced reagent(cIR).As a result,the racemate MOFs can be driven to generate absolute homochiral *** two achiral MOFs[cd(D-cam)(TPPP)_(0.5)](AF-1,AF=achiral framework)and[cd(L-cam)(TPPP)_(0.5)](AF-2)were *** position disorder of D/L-cam skeleton causes the generation of nonchiralization,further leading to disappearance of symmetry breaking of *** the perspective of structure,this is the first report which reveals the chiral transfer and nonchiralization between chiral induced agents and tetradentate ***,DcF-17 and LcF-17 show cPL with luminescence dissymmetry factor(glum)of–1.0×10^(-2)and+9.2×10^(–3),*** work provides the useful evidences to reveal the induced chiral crystallization and the construction of cPL-active crystalline materials.

关键词： Metal-organic frameworks circularly polarized luminescence chirality induction Spontaneous resolution chirality transfer

Simultaneous acceleration of sulfur reduction and oxidation on bifunctional electrocatalytic electrodes for quasi-solid-state Zn–S batteries

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Sc.ence china chemistry 2024年第5期67卷 1531-1538页

作者： Mingli Wang hong Zhang Tianhang ding Fangjun Wu Lin Fu Bin Song Pengfei cao Ke Lu Institutes of Physical Sc.ence and Information Technology School of Materials Science and EngineeringKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei 230601China Hefei National Laboratory for Physical Sc.ences at the Microscale University of Science and Technology of ChinaHefei 230026China School of chemistry and chemical engineering Harbin Institute of TechnologyHarbin 150001China School of chemistry and chemical engineering Guizhou UniversityGuiyang 550025China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123China State Key Lab of Organic-Inorganic composites Beijing University of Chemical TechnologyBeijing 100029China

The incomplete sulfur reduction and high ZnS re-oxidation energy barrier along with severe side reactions during the battery cycling compromise the practical application of Zn–S electrochemistry. Herein, a bifunctional electrocatalytic sulfur matrix that simultaneously accelerates the sulfur reduction and ZnS oxidation is proposed to realize a highly-effic.ent Zn–S cell. It is revealed that the N-heteroatom hotspots are more favorable for facilitating the conversion of S to ZnS while the coO nanocrystal substantially lowers the ZnS activation energy barrier thereby suppressing the formation of disproportionation species(e.g.,SO_(4)^(2-)) and accumulation of inactive ZnS. Accordingly, the co O anchored on the N-doped carbon-supported sulfur cathode delivers a high Zn^(2+)storage capacity of 1,172 m Ahg^(-1)and outstanding cycling stability with a capacity retention of 71.6% after500 cycles with a high average coulombic effic.ency of 97.8%. Simultaneously, the stable cycling of solid-state Zn–S pouch cells with an energy density of 585 Whkg^(-1)sulfuris also demonstrated. Moreover, the postmortem analysis reveals that the degradation of Zn–S cells is mainly attributed to the limited reversibility of Zn anodes rather than the ZnS decomposition and/or accumulation. The approach to the bidirectional catalysis manipulated the sulfur redox provides a new perspective to realize the theoretical potentials of Zn–S cells.

关键词： Zn–S battery bifunctional catalysts solid-state battery sulfur redox degradation mechanism

changes in global land surface frozen ground and freeze-thaw processes during 1950-2020 based on ERA5-Land data

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Advances in climate change Research 2024年第2期15卷 265-274页

作者： Yong YANG Ren-Sheng c.en Yong-Jian ding hong-Yuan LI Zhang-Wen LIU Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China State Key Laboratory of cryospheric Sc.ences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China Shandong Provincial Key Laboratory of Water and Soil conservation and environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China

Frozen ground(FG)plays an important role in global and regional climates and environments through changes in land freeze-thaw processes,which have been conducted mainly in different ***,the changes in land surface freeze-thaw processes under climate change on a global scale are still *** on ERA5-Land hourly land skin temperature data,this study evaluated changes in the global FG area,global land surface first freeze date(FFD),last freeze date(LFD)and frost-free period(FFP)from 1950 to *** results show that the current FG areas(1991-2020 mean)in the Northern Hemisphere(NH),Southern Hemisphere(SH),and globe are 68.50×10^(6),9.03×10^(6),and 77.53×10^(6)km^(2),which account for 72.4%,26.8%,and 60.4%of the exposed land(excluding glaciers,ice sheets,and water bodies)in the NH,SH and the globe,respectively;further,relative to 1951-1980,the FG area decreased by 1.9%,8.8%,and 2.8%,*** FG at lower latitudes degrades to intermittently FG,and intermittently FG degrades to non-frozen ground,which caused the global FG boundary to retreat to higher latitudes from 1950 to *** annual FG areas in the NH,SH,and globe all show significant decreasing trends(pcade,*** FFP prolongation in the NH is mainly influenced by LFD advance,while in the SH it is mainly controlled by FFD *** prolongation trend of FFP in the NH(1.34 d per decade)is larger than that in the SH(1.15 d per decade).

关键词： Frozen ground Freeze-thaw processes Frost-free period First freeze date Global warming