检索结果-南通市图书馆

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

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

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

Decision and coordination of an E-commerce Supply chain considering Returns and Network Externalities

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Sc.ence and Systems engineering 2024年第5期33卷 552-575页

作者： Liang Shen Fei Lin Yuyan Wang Luping ding T.c.E.c.eng Dexia Wang School of Public Finance and Taxation Shandong University of Finance and Economicsjinan 250014China bschool of Management Sc.ence and engineering Shandong University of Finance and EconomicsJinan 250014China PolyU Business School The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077China

considering the large number of returns in online sales and the network externalities of e-platforms,we develop a decentralized model and a centralized model to explore the impacts of returns and network externalities on e-commerce supply chain(EcSc)*** show that in the decentralized model,the service level,price,market demand,and EcSc members’profits increase with the network externality ***,the service level and price increase,while the market demand and EcSc members’profits decrease with the product return *** centralized model is the optimal operating mode when it is properly *** design the“commission and return cost-sharing”contract to optimize EcSc,in which the proportion of the e-platform’s sharing of the return handling cost is exactly equal to the proportion of the system profit after *** on the decentralized model,we develop two extended models in which we endogenize the impacts of the service level and return rate on the network externality *** comparisons between the extended and decentralized models,we show that high-quality service can improve EcSc’s profitability,while a high return rate hurts its economic performance.

关键词： E-commerce supply chain coordination mechanism network externalities return products

Theoretical and experimental study of a bi-stable piezoelectric.energy harvester under hybrid galloping and band-limited random excitations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(english Edition) 2024年第3期45卷 461-478页

作者： Haitao LI Tianyu ZHenG Weiyang QIN Ruilan TIAN Hu ding J.c.JI Liqun c.en Department of engineering Mechanics North University of ChinaTaiyuan 030051China Department of engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China Department of engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang 050043China Shanghai Key Laboratory of Mechanics in energy engineering Shanghai Frontier Science Center of MechnoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200072China School of Mechanical and Mechatronic.engineering University of Technology SydneyNew South Wales 2007Australia

In the practical environment,it is very common for the simultaneous occurrence of base excitation and *** the combined energy of vibration and wind with a single energy harvesting structure is *** this purpose,the effects of the wind speed and random excitation level are investigated with the stochastic averaging method(SAM)based on the energy *** results of the analytical prediction are verified with the Monte-carlo method(McM).The numerical simulation shows that the introduction of wind can reduce the critical excitation level for triggering an inter-well jump and make a bi-stable energy harvester(BEH)realize the performance enhancement for a weak base ***,as the strength of the wind increases to a particular level,the influence of the random base excitation on the dynamic responses is weakened,and the system exhibits a periodic galloping response.A comparison between a BEH and a linear energy harvester(LEH)indicates that the BEH demonstrates inferior performance for high-speed *** experiments are conducted to investigate the validity of the theoretical prediction and numerical *** experimental findings also show that strong random excitation is favorable for the BEH in the range of low wind ***,as the speed of the incoming wind is up to a particular level,the disadvantage of the BEH becomes clear and evident.

关键词： bi-stability inter-well response galloping band-limited random

Insight into Metabolomic Profiling of Tinospora cordifolia: Recent Advances and Future Perspectives of Quality control

在线全文

学校读者我要写书评

暂无评论

World Journal of Traditional chinese Medicine 2024年第2期10卷 137-148页

作者： Atiqul Islam c.Anurag Nazia Siddiqui Xianting ding Alok Sharma college of Pharmacy JSS Academy of Technical EducationNoidaUttar PradeshIndia Department of Pharmaceutical Technology MIETMeerutUttar PradeshIndia Institute for Personalized Medicine School of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina

The objective of this study was to offer a review of previous works on Tinospora cordifolia(Tc) metabolomics with a highlight on the use of metabolomics in comparative evaluations between varieties and selection of optimum cultivation, collection, and extraction procedures, providing insights into pharmaceutical and food product quality monitoring. Scholarly databases were searched to gather relevant information on Tc's therapeutic usefulness, phytoconstituent studies, metabolomics, and applications. Pub chem was used to learn the structures of several of the metabolites. The various medicinal properties of Tc were extensively researched. The most essential portions of the plant in Ayurvedic medicines are the stems. Bioactive phytochemicals such as steroidal lactones, alkaloids, diterpenoids, and phenolic compounds are present in the roots and leaves. Metabolomic analysis revealed that, in addition to the season and geographical region of the sample collected, the metabolite profiles of Tc also depend on the parts of the plant taken as a sample and also the plant's stage of growth. The amounts of secondary metabolites differed between morpho/chemotypes within the Tc species. Despite the fact that research on Tc began several decades ago, the diversity of phytoconstituents was not appreciated because of a lack of reliable techniques for phytochemical fingerprinting. The uncovering of several novel metabolites was aided by advances in chromatography combined with mass spectrometry. To produce a full metabolomic profile, researchers used mutually complementary techniques. Following that, data analysis and searches against spectrum databases allowed for signal annotation and interpretation of metabolites in large quantities without separating them separately. The current review includes a critical assessment of metabolomic data and an overview of the technique's various applications. It is vital to establish the metrics of quality control of herbal medicines in order to

关键词： Analytical tools metabolomics quality control secondary metabolites Tinospora cordifolia

Optimization of resource allocation in FDD massive MIMO systems

在线全文

学校读者我要写书评

暂无评论

Digital communications and Networks 2024年第1期10卷 117-125页

作者： Jun cai chuan Yin Youwei ding School of Artificial Intelligence and Information Technology Nanjing University of Chinese MedicineNanjing 210046China School of Electronic and Information Hangzhou Dianzi UniversityHangzhou 310018ZhejiangChina

The performance of massive MIMO systems relies heavily on the availability of channel State Information at the Transmitter(cSIT).A large amount of work has been devoted to reducing the cSIT acquisition overhead at the pilot training and/or csI feedback *** fact,the downlink communication generally includes three stages,i.e.,pilot training,csI feedback,and data *** three stages are mutually related and jointly determine the overall system ***,there exist few studies on the reduction of csIT acquisition overhead from the global point of *** this paper,we integrate the Minimum Mean Square Error(MMSE)channel estimation,Random Vector Quantization(RVQ)based limited feedback and Maximal Ratio combining(MRc)precoding into a unified framework for investigating the resource allocation *** particular,we first approximate the covariance matrix of the quantization error with a simple expression and derive an analytical expression of the received Signal-to-Noise Ratio(SNR)based on the deterministic equivalence *** the three performance metrics(the spectral effic.ency,energy effic.ency,and total energy consumption)oriented problems are formulated *** practical system requirements,these three metrics can be collaboratively ***,we propose an optimization solver to derive the optimal partition of channel coherence *** results verify the benefits of the proposed resource allocation schemes under three different scenarios and illustrate the tradeoff of resource allocation between three stages.

关键词： Massive MIMO FDD cSIT Resource allocation

Three-dimensional visualization technology for guiding one-step percutaneous transhepatic cholangioscopic lithotripsy for the treatment of complex hepatolithiasis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第28期30卷 3393-3402页

作者： Yong-Qing Ye Ya-Wen cao Rong-Qi Li en-Ze Li Lei Yan Zhao-Wei ding Jin-Ming Fan Ping Wang Yi-Xiang Wu Department of Hepatobiliary Surgery The Second People’s Hospital of FoshanFoshan 528000Guangdong ProvinceChina Department of Emergency Medicine Biomedical Innovation CenterThe Sixth Affiliated HospitalSun Yat-sen UniversityGuangzhou 510655Guangdong ProvinceChina Department of Hepatobiliary Surgery Foshan Hospital of Traditional Chinese MedicineFoshan 528000Guangdong ProvinceChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510282Guangdong ProvinceChina Department of Gastrointestinal Surgery The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510120Guangdong ProvinceChina

BAcKGROUND Biliary stone disease is a highly prevalent condition and a leading cause of hospitalization *** with associated strictures has high residual and recurrence rates after traditional multisession percutaneous transhepatic cholangioscopic lithotripsy(PTcSL).AIM To study one-step PTcSL using the percutaneous transhepatic one-step biliary fistulation(PTOBF)technique guided by three-dimensional(3D)*** This was a retrospective,single-center study analyzing,140 patients who,between October 2016 and October 2023,underwent one-step PTcSL for *** patients were divided into two groups:The 3D-PTOBF group and the PTOBF *** clearance on choledochoscopy,complications,and long-term clearance and recurrence rates were *** Age,total bilirubin,direct bilirubin,child-Pugh class,and stone location were similar between the 2 groups,but there was a significant difference in bile duct strictures,with biliary strictures more common in the 3D-PTOBF group(P=0.001).The median follow-up time was 55.0(55.0,512.0)*** immediate stone clearance ratio(88.6%vs 27.1%,P=0.000)and stricture resolution ratio(97.1%vs 78.6%,P=0.001)in the 3D-PTOBF group were significantly greater than those in the PTOBF *** complication(8.6%vs 41.4%,P=0.000)and stone recurrence rates(7.1%vs 38.6%,P=0.000)were significantly lower in the 3D-PTOBF *** Three-dimensional visualization helps make one-step PTcSL a safe,effective,and promising treatment for patients with complicated primary *** perioperative and long-term outcomes are satisfactory for patients with complicated primary *** minimally invasive method has the potential to be used as a substitute for hepatobiliary surgery.

关键词： Hepatolithiasis One-step percutaneous transhepatic cholangioscopic lithotripsy Biliary disease Three-dimensional visualization clinical efficacy

Effect of hot isostatic pressure on the microstructure and tensile properties of γ'-strengthened superalloy fabricated through induction-assisted directed energy deposition

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1089-1097页

作者： Jianjun Xu Hanlin ding Xin Lin Feng Liu Analytical&Testing center Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The microstructure characteristics and strengthening mechanism of Inconel738Lc(IN-738Lc) alloy prepared by using induction-assisted directed energy deposition(IDED) were elucidated through the investigation of samples subjected to IDED under 1050℃ preheating with and without hot isostatic pressing(HIP,1190℃,105 MPa,and 3 h).Results show that the as-deposited sample mainly consisted of epitaxial columnar crystals and inhomogeneously distributed γ’ phases in interdendritic and dendritic core *** HIP,grain morphology changed negligibly,whereas the size of the γ’ phase became increasingly *** further heat treatment(HT,1070℃,2 h + 845℃,24 h),the γ’ phase in the as-deposited and HIPed samples presented a bimodal size distribution,whereas that in the as-deposited sample showed a size that remained *** comparison of tensile properties revealed that the tensile strength and uniform elongation of the HIP + HTed sample increased by 5% and 46%,respectively,due to the synergistic deformation of bimodal γ’phases,especially large cubic γ’ ***,the relationship between phase transformations and plastic deformations in the IDEDed sample was discussed on the basis of generalized stability theory in terms of the trade-off between thermodynamics and kinetics.

关键词： directed energy deposition Ni-based superalloys high-temperature preheating hot isostatic pressing microstructure tensile properties