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Study of the pressure transient behavior of directional wells considering the effect of non-uniform flux distribution

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Petroleum Science 2024年第3期21卷 1765-1779页

作者： yan-Zhong liang Bai-Lu Teng Wan-Jing Luo School of Energy Resources China University of Geosciences(Beijing)Beijing100083China

During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional ***,in all existing studies,it is oversimplified to a uniform flux distribution,which can result in inaccurate results for field ***,this paper proposes a semi-analytical model of a directional well based on the assumption of non-uniform flux ***,the direction well is discretized into a carefully chosen series of linear sources,such that the complex well trajectory can be captured and the nonuniform flux distribution along the wellbore can be considered to model the three-dimensional flow *** using the finite difference method,we can obtain the numerical solutions of the transient flow within the *** the aid of Green's function method,we can obtain the analytical solutions of the transient flow from the matrix to the *** complete flow behavior of a directional well is perfectly represented by coupling the above two types of transient ***,on the basis of the proposed model,we conduct a comprehensive analysis of the pressure transient behavior of a directional *** computation results show that the flux variation along the direction well has a significant effect on pressure *** addition,the directional well in an infinite reservoir may exhibit the following flow regimes:wellbore afterflow,transition flow,inclined radial flow,elliptical flow,horizontal linear flow,and horizontal radial *** horizontal linear flow can be observed only if the formation thickness is much smaller than the well ***,a dip region that appears on the pressure derivative curve indicates the three-dimensional flow behavior near the wellbore.

关键词： Directional well Pressure transient behavior Semi-analytical model Non-uniform flux

Fine-grained grid computing model for Wi-Fi indoor localization in complex environments

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Journal of Electronic Science and Technology 2024年第1期22卷 42-52页

作者： yan liang Song Chen Xin Dong Tu Liu School of Computer Engineering Chengdu Technological UniversityChengdu611730China HAN Networks Corporation Limited Beijing100094China

The fingerprinting-based approach using the wireless local area network(WLAN)is widely used for indoor ***,the construction of the fingerprint database is quite *** when the position of the access point(AP)or wall changes,updating the fingerprint database in real-time is *** appropriate indoor localization approach,which has a low implementation cost,excellent real-time performance,and high localization accuracy and fully considers complex indoor environment factors,is preferred in location-based services(LBSs)*** this paper,we proposed a fine-grained grid computing(FGGC)model to achieve decimeter-level localization *** points(RPs)are generated in the grid by the FGGC ***,the received signal strength(RSS)values at each RP are calculated with the attenuation factors,such as the frequency band,three-dimensional propagation distance,and walls in complex *** a result,the fingerprint database can be established automatically without manual measurement,and the efficiency and cost that the FGGC model takes for the fingerprint database are superior to previous *** proposed indoor localization approach,which estimates the position step by step from the approximate grid location to the fine-grained location,can achieve higher real-time performance and localization accuracy *** mean error of the proposed model is 0.36 m,far lower than that of previous ***,the proposed model is feasible to improve the efficiency and accuracy of Wi-Fi indoor *** also shows high-accuracy performance with a fast running speed even under a large-size *** results indicate that the proposed method can also be suitable for precise marketing,indoor navigation,and emergency rescue.

关键词： Fine-grained grid computing (FGGC) Indoor localization Path loss Random forest Reference points(RPs)

Microstructure,wear and friction behavior of CoCrAITaY-xCNTs composite coatings deposited by laser-induction hybrid cladding

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Rare Metals 2024年第4期43卷 1815-1827页

作者： Sheng-Feng Zhou Yu Long yan-liang Yi Cheng Deng Lian-Xi Hu Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China MOE Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning530004China School of Mechatronics Engineering Guangdong Polytechnic Normal UniversityGuangzhou510635China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes(CNTs)chemically reacted with Ta to form reinforcement phase(TaC),while the other CNTs were retained as lubrication ***,the CoCrAlYTa-xCNTs(x=0,1,2,and 4;wt%)composite coatings were prepared by laserinduction hybrid cladding(LIHC),and the microstructure and wear resistance of coatings were systematically *** show that the coatings are mainly composed of TaC,y-(Co,Cr)andβ-(Co,Cr)*** the CNTs content increases from 0 wt%to 4 wt%,the volume fraction of TaC increases from 13.11 vol%to 16.12 vol%.Meanwhile,the nano-hardness ofγ-(Co,Cr)andβ-(Co,Cr)Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,*** a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4×10^(-3)to 6.1×10^(-3)mg·m^(-1),and the average friction coefficient decreases from 0.55 to *** good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding

Catalytic behavior of Mo-Bi-Fe-Co-K-M-O(M=Ce,Gd,CeGd)catalysts for selective oxidation of isobutene

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Journal of Rare Earths 2024年第1期42卷 84-93,I0003页

作者： Qinghui Li Huahua Zhao Jian yang Jun Zhao liang yan Huanling Song Lingjun Chou State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing100049China

The further improvement of methacrolein(MAL)selectivity from isobutene(IB)oxidation is crucial and *** this study,based on the typical Mo-Bi-Fe-Co-K-O mixed metal oxide,the rare earth element Gd-doped,Ce-doped and CeGd co-doped catalysts were prepared by co-precipitation strategy to increase the selectivity of MAL from 47.9%to 49.8%,64.2% and 68.6%,*** order to elucidate in-depth the promoting effect of Ce and/or Gd,various characterizations were utilized including X-ray diffraction patterns(XRD),Raman,X-ray fluorescence spectrometry(XRF),X-ray photoelectron spectroscopy(XPS),O_(2)-temperature programmed desorption(O_(2)-TPD),H2-temperature programmed reduction(H2-TPR),CO_(2)-temperature programmed desorption(CO_(2)-TPD),IB-temperature programmed desorption(i-C4-TPD)and in-situ IB-Fourier transform infrared spectroscopy(IB-FTIR).Both Ce and Gd finely regulate the bulk and surface structure of the catalyst,thus altering the redox ability,oxygen mobility and storage ability and *** with Ce,Gd addition slightly regulates the variation of Co^(2+)/Co^(3+)redox couples,greatly enhances the interaction among the components on the catalyst,thus only increases the content of surface oxygen species and has little effect on their *** Cecontaining catalyst performs stronger oxygen storage and migration ability,thus leading to the overproduction of surface Odefectspecies,which are proposed to be the active sites for the production of MAL and *** CeGd co-doped catalyst possesses the proper content of surface Odefectspecies,thus exhibits much higher MAL ***,the promoting mechanism of Ce and/or Gd over IB oxidation is ***,this work is helpful for understanding the influence of rare earth elements on the structure of mixed metal oxides and the olefin selective oxidation reaction.

关键词： Mixed metal oxide catalyst Rare earth element Isobutene Selective oxidation Methacrolein

Recent progress in Prussian blue electrode for electrochromic devices

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Frontiers in Energy 2024年第2期18卷 160-186页

作者： Yongting ZHANG Wanzhong LI Hui GONG Qianqian ZHANG liang yan Hao WANG Key Laboratory for New Functional Materials of the Ministry of Education Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China School of Instrument Science and Engineering Southeast UniversityNanjing 210096China Beijing Aerospace Times Laser Inertial Technology Company Beijing 100094China

Great progress has been made in the electrochromic(EC)technology with potential applications in various *** one of the most promising EC materials,Prussian blue(PB)has attracted great attention due to its excellent EC performance,such as low cost,easy synthesis,rich color states,chemical stability,suitable redox potential,and fast color-switching *** review summarizes the recent progress in PB electrodes and devices,including several typical preparation techniques of PB electrodes,as well as the recent key strategies for enhancing EC performance of PB ***,PB-based electrochromic devices(ECDs)have been widely used in various fields,such as smart windows,electrochromic energy storage devices(EESDs),wearable electronics,smart displays,military camouflage,and other *** opportunities and obstacles are suggested for advancing the development of PB-based *** comprehensive review is expected to offer valuable insights for the design and fabrication of sophisticated PBbased ECDs,enabling their practical integration into realworld applications.

关键词： Prussian blue electrochromism energy storage smart windows

High-resolution mid-infrared single-photon upconversion ranging

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Photonics Research 2024年第6期12卷 1294-1302页

作者： SHUHONG JIANG KUN HUANG TINGTING YU JIANAN FANG BEN SUN yan liang QIANG HAO E.WU MING yan HEPING ZENG State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200062China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401121China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China School of Optical Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Research Center for Quantum Sciences Shanghai 201315China Guangyang Bay Laboratory Chongqing Institute for Brain and IntelligenceChongqing 400064China

Single-photon laser ranging has widespread applications in remote sensing and target ***,highly sensitive light detection and ranging(lidar)has long been restricted in the visible or near-infrared *** appealing quest is to extend the operation wavelength into the mid-infrared(MIR)region,which calls for an infrared photon-counting system at high detection sensitivity and precise temporal ***,we devise and demonstrate an MIR upconversion lidar based on nonlinear asynchronous optical ***,the infrared probe is interrogated in a nonlinear crystal by a train of pump pulses at a slightly different repetition rate,which favors temporal optical scanning at a picosecond timing resolution and a kilohertz refreshing rate ***,the cross-correlation upconversion trace is temporally stretched by a factor of 2×10^(4),which can thus be recorded by a low-bandwidth silicon *** combination with the time-correlated photon-counting technique,the achieved effective resolution is about two orders of magnitude better than the timing jitter of the detector itself,which facilitates a ranging precision of 4μm under a low detected flux of 8×10^(−5) photons per *** presented MIR time-of-flight range finder is featured with single-photon sensitivity and high positioning resolution,which would be particularly useful in infrared sensing and imaging in photon-starved scenarios.

关键词： resolution lidar repetition

Urgent one-stage endoscopic treatment for choledocholithiasis related moderate to severe acute cholangitis: A propensity scorematched analysis

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World Journal of Gastroenterology 2024年第15期30卷 2118-2127页

作者： yang Zhou Yin-Qiu Zhang Shuai-Jing Huang yan liang Xiao liang Masoom Wali Ya-Dong Feng Department of Gastroenterology Zhongda HospitalSchool of MedicineSoutheast UniversityNanjing 210009Jiangsu ProvinceChina Department of Gastroenterology BenQ Medical CenterThe Affiliated BenQ Hospital of Nanjing Medical UniversityNanjing 210019Jiangsu ProvinceChina

BACKGROUND During emergency endoscopic retrograde cholangiopancreatography(ERCP),the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis(AC)due to choledocholithiasis are *** To investigate the safety and feasibility of one-stage endoscopic treatment for moderate to severe *** We enrolled all patients diagnosed with moderate to severe cholangitis due to common bile duct stones from January 2019 to July *** outcomes were compared in this study between patients who underwent ERCP within 24 h and those who underwent ERCP 24 h later,employing a propensity score(PS)*** primary outcomes were intensive care unit(ICU)admission rates,ICU length of stay,and duration of antibiotic *** In total,we included 254 patients and categorized them into two groups based on the time elapsed between admission and intervention:The urgent group(≤24 h,n=102)and the elective group(>24 h,n=152).Ninety-three pairs of patients with similar characteristics were selected by PS *** urgent ERCP group had more ICU admissions(34.4%vs 21.5%,P=0.05),shorter ICU stays(3 d vs 9 d,P<0.001),fewer antibiotic use(6 d vs 9 d,P<0.001),and shorter hospital stays(9 d vs 18.5 d,P<0.001).There were no significant differences observed in adverse events,in-hospital mortality,recurrent cholangitis occurrence,30-d readmission rate or 30-d *** Urgent one-stage ERCP provides the advantages of a shorter ICU stay,a shorter duration of antibiotic use,and a shorter hospital stay.

关键词： Acute cholangitis Endoscopic retrograde cholangiopancreatography One-stage treatment Optimal time

台湾地区技职本科教育的政策演进、发展特征和借鉴启示

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职教论坛 2024年第7期40卷 102-110页

作者：梁燕北京教育科学研究院

技职教育在我国台湾地区经济社会发展中发挥着重要作用，提供强有力的人力资源支撑，其中本科层次占据主体。20世纪90年代中期以来，技职本科教育经历了快速扩张、稳步发展和优化调整三个重要阶段。相关部门推动系列重要政策和组织实施... 详细信息

技职教育在我国台湾地区经济社会发展中发挥着重要作用，提供强有力的人力资源支撑，其中本科层次占据主体。20世纪90年代中期以来，技职本科教育经历了快速扩张、稳步发展和优化调整三个重要阶段。相关部门推动系列重要政策和组织实施相应计划，既促进改革发展也努力纠正偏误。大陆正处于建设完善现代职业教育体系和大力发展职教本科的关键期，可借鉴台湾地区技职本科发展经验，同时深刻分析其教训并做好风险防范。以经济社会需求为导向，合理规划职业本科教育发展路径和规模；坚定职业教育类型，强化职业本科教育内涵发展的政策供给；完善质量保障体系，以督导评估护航职业本科教育健康发展。

关键词：台湾地区技职本科科技校院政策演进

Therapeutic Effect of Rhodopseudomonas palustris-Bioconverted Extract of Lycium barbarum on Rats with Lead Exposure

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Biomedical and Environmental Sciences 2024年第4期37卷 440-444页

作者： yanG Hong SUN Yi CHAI Shu Tong liang yan Hui LIU Ya Ni yanG Guan E School of Pharmacy Shanxi Medical UniversityTaiyuan 030001ShanxiChina

Lead is a ubiquitous pollutant and Pb pollution is a global public health *** has been reported to induce multiple adverse effects,including reproductive toxicity,neurotoxicity,carcinogenicity,nephrotoxicity,immunotoxicity,and hypertension[1].The traditional medical treatment available for Pb poisoning is chelation,which can save lives in individuals with very high blood Pb *** commonly used chelating agents include CaNa2EDTA and meso-2,3-dimercaptosuccinic ***,chelation therapy has strong short-term effects on the overall long-term management of Pb exposure.

关键词： converted chelation chelating