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Mechanisms of fracture propagation from multi-cluster using a phase field based HMD coupling model in fractured reservoir

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Petroleum Science 2024年第3期21卷 1829-1851页

作者： yun-jin wang Bo wang Hang Su Tu Chang Ren-Cheng Dong Li-Zhe Li Wei-Yu Tang Ting-Xue Jiang Fu-Jian Zhou State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBejing2249China China University of Petroleum-Beijing at Karamay Karamay834000XinjiangChina China National Oil and Gas Exploration and Development Corporation Ltd. Beijing100034China University of Texas at Austin United States SINOPEC Research Institute of Petroleum Engineering Beijing100101China

Natural fractures(NFs)are common in shale and tight reservoirs,where staged multi-cluster fracturing of horizontal wells is a prevalent technique for reservoir *** NFs and stress interference are recognized as significant factors affecting hydraulic fracture(HF)propagation,the combined influence of these factors remains poorly *** address this knowledge gap,a novel coupled hydromechanical-damage(HMD)model based on the phase field method is developed to investigate the propagation of multi-cluster HFs in fractured *** comprehensive energy functional and control functions are established,while incorporating dynamic fluid distribution between multiple perforation clusters and refined changes in rock mechanical parameters during hydraulic *** HMD coupled multi-cluster HF propagation model investigates various scenarios,including single HF and single NF,reservoir heterogeneity,single HF and NF clusters,and multi-cluster HFs with NF *** results show that the HMD coupling model can accurately capture the impact of approach angle(θ),stress difference and cementation strength on the interaction of HF and *** criterion of the open and cross zones is not *** NF angle(a)is not a decisive parameter to discriminate the *** to the relationship between approach angle(θ)and NF angle(a),the contact relationship of HF can be divided into three categories(θ=a,θa).The connected NF can increase the complexity of HF by inducing it to form branch fracture,resulting in a fractal dimension of HF as high as2.1280 at angles of±45°.Inter-fracture interference from the heel to the toe of HF shows the phenomenon of no,strong and weak ***,under the influence of NFs,distant HFs from the injection can become dominant ***,as a gradually increases,inter-fracture stress interference becomes the primary factor influencing HF propagation,gradually superseding the dominance of NF

关键词： HMD coupling Phase field Natural fracture Flow distribution Hydraulic fracturing Inter-fracture interference

Simulation of Secondary Dendritic Arm Spacing of Free Cutting Steel 38MnVS

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Journal of Iron and Steel Research International 2011年第6期18卷 54-60,73页

作者： XIA yun-jin wang Fu-ming wang jin-long School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The secondary dendritic arm spacing （SDAS） of free cutting steel 38MnVS during continuous casting process was simulated based on a Mixed Lagrangian and Eulerian Method （MILE Method） and SDAS model. The simulation results are basically in agreement with measured ones. The effect of composition, superheat and casting speed on SDAS are studied, and the relationship between SDAS and interdendritic segregation is discussed. The results show that SDAS increases with increasing carbon and silicon content, and decreases with increasing manganese and sulfur content. The increase of superheat and casting speed also makes SDAS increase. The permeability of co lumnar mushy zone which is parallel to the primary dendritic arms is calculated based on Carman-Kozeny relationship, and the increase of SDAS makes the permeability increase, which exacerbates interdendritic segregation of columnar crystal zone.

关键词： MiLE method secondary dendritic arm spacing permeability interdendritic segregation

Effect of SO_2 on the performance of Ag-Pd/Al_2O_3 for the selective catalytic reduction of NOx with C_2H_5OH

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Journal of Environmental Sciences 2006年第5期18卷 973-978页

作者： XIE Shu-xia YU yun-bo wang jin HE Hong State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The influence of SO2 on the performance of Ag-Pd/Al2O3 for the selective catalytic reduction （SCR） of NOx with C2H5OH was investigated experimentally. The activity test results suggest that Ag-Pd/Al2O3 shows a small activity loss in the presence of SO2 when using C2H5OH as a reductant. In situ DRIFTS spectra show that the activity loss originates from the formation of surface sulphate species on the Ag-Pd/Al2O3. The surface sulphate species formation inhibits the formation of nitrate, whereas hardly changes the partial oxidation of C2H5OH. Compared with the NOx reduction by C3H6, an obvious suppression of the surface sulphate species formation was observed by DRIFTS experiment when using C2H5OH as a reductant. This phenomenon reveals the better catalytic performance and strong SO2 tolerance of Ag-Pd/Al2O3-C2H50H system.

关键词： sulphate SCR nitrate enolic species isocyanate reaction mechanism

Sensitized ligand narrow-band phosphorescence for high-efficiency solution-processed OLEDs

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Science China Chemistry 2022年第8期65卷 1559-1568页

作者： Qian wang jin-yun wang Hao Zeng Li-Yi Zhang Zhong-Ning Chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China University of Chinese Academy of Sciences Beijing 100039China

Narrow-band emission is crucial for high color purity in panel ***,attaining narrow-band emission is highly challenging because either thermally activated delayed fluorescence or phosphorescence in organic and metal-organic compounds originates primarily from multiple charge transfer transitions featured with broad *** this work,a general tactic for achieving highly efficient narrow-band emission is proposed by the sensitization of ligand-centered phosphorescence through substantial intermetallic *** to weak phosphorescence in mononuclear Pt(Ⅱ)precursors,highly efficient ligand-centered phosphorescence is dramatically activated in Pt(Ⅱ)-Au(Ⅰ)heteronuclear complexes with quantum yield as high as 81%in solutions and 97%in doping ***-efficiency solution-processed organic light-emitting diodes(OLEDs)with narrow-band emission are successfully attained with external quantum efficiency(EQE)of 21.6%and a full width at half maxima(FWHM)of 36 nm for yellow electroluminescence and EQE of 20.8%and FWHM of 32 nm for green electroluminescence.

关键词： electroluminescence narrow-band emission organic light-emitting diode phosphorescence solution process

Methanol-induced luminescence vapochromism based on a Sb^(3+)-doped organic indium halide hybrid

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Science China Materials 2022年第7期65卷 1876-1881页

作者： Cui-Mi Shi jin-Long Li Liang-jin Xu Yue Wu Hong-Li Xuan jin-yun wang Zhong-Ning Chen College of Chemistry Fuzhou UniversityFuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

Ion doping has been demonstrated as a practical approach to achieving highly efficient luminescence in both inorganic phosphors and organic-inorganic *** asformed doping species show great potential in optoelectronic applications due to their high photoluminescence quantum yield(PLQY)and excellent ***,we report highly emissive Sb^(3+)-doped indium halides(C_(6)H_(18)N_(2))InCl_(5)·H_(2)O:Sb(C_(6)H_(18)N_(2)^(2+)=N,N,N',N'-tetramethylethane-1,2-diammonium)prepared by solution evaporation methods with an emission that peaked at 565 nm and a PLQY of 74.6%.Photophysical characterizations and density functional theory computational studies verify the broadband emission originating from a self-trapped ***,a drastic red shift of the emission peak from 565 to 663 nm with yellow luminescence turning to red is observed once the(C_(6)H_(18)N_(2))InCl_(5)·H_(2)O:Sb hybrid is exposed to methanol ***,when the methanol-exposed hybrid is put in air,the emission reverts to 565 nm in several ***-crystal X-ray diffraction studies show a subsequent structure distortion upon the coordination of methanol to the Sb(III)center,which is responsible for the drastic red shift of the ***,we found that(C_(6)H_(18)N_(2))InCl_(5)·H_(2)O:Sb exhibits a specific response to methanol vapor after screening a series of volatile organic compounds with different ***,a negligible change of the emission intensity is observed after several cycles of uptaking and releasing *** high fatigue resistance and specific solvent response of the Sb^(3+)-doped indium halide make it a very promising methanol detector.

关键词： organic metal halide hybrid Sb^(3+) doped self-trapped exciton emission luminescence vapochromism

Current optimization-based control of dual three-phase PMSM for low-frequency temperature swing reduction

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Defence Technology（防务技术） 2024年第4期34卷 238-246页

作者： Linlin Lu Xueqing wang Luhan jin Qiong Liu yun Zhang Yao Mao Key Laboratory of Optical Engineering Chinese Academy of SciencesChengdu 610209China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China University of Chinese Academy of Sciences Beijing 100049China College of Electrical Engineering Sichuan UniversityChengdu 610065China

In this paper,a control scheme based on current optimization is proposed for dual three-phase permanent-magnet synchronous motor(DTP-PMSM)drive to reduce the low-frequency temperature *** reduction of temperature swing can be equivalent to reducing maximum instantaneous phase copper loss in this ***,a two-level optimization aiming at minimizing maximum instantaneous phase copper loss at each electrical angle is ***,the optimization is transformed to a singlelevel optimization by introducing the auxiliary variable for easy *** that singleobjective optimization trades a great total copper loss for a small reduction of maximum phase copper loss,the optimization considering both instantaneous total copper loss and maximum phase copper loss is proposed,which has the same performance of temperature swing reduction but with lower total *** this way,the proposed control scheme can reduce maximum junction temperature by 11%.Both simulation and experimental results are presented to prove the effectiveness and superiority of the proposed control scheme for low-frequency temperature swing reduction.

关键词： Dual three-phase PMSM Low-frequency temperature swing Copper loss Current optimization Connected neutral points

Freezing the conductance of platinum(Ⅱ)complexes by quantum interference effect

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Chinese Chemical Letters 2022年第6期33卷 3263-3266页

作者： Sai-Sai Yan jin-yun wang Zi-You Pan Da-Sheng Zheng Qian-Chong Zhang Zhong-Ning Chen Fujian Normal University Fuzhou 350007China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

Understanding the impact of substituents on the quantum interference effect at single molecule scale is of great importance for the design of molecular *** this work,three platinum(Ⅱ)complexes with–H,–NH_(2)and–NO_(2)groups on conductive backbones were designed and ***-molecule conductance,which was measured using scanning tunnelling microscope break junction(STM-BJ)technique,demonstrated a conductance freeze phenomenon under the variation of *** study revealed that,despite the electronic effect of the substituents shifting the energy level of molecular orbital,the quantum interference effect vanished the influence of electronic effect on the conductance and eventually leaded to the conductance freeze.

关键词： Platinum(Ⅱ)complex Electronic effect Single-molecule conductance Quantum interference Magic ratio rule

Structures and luminescence properties of two copper(I) halide complexes featuring 2-(2-benzimidazolyl)-6-methylpyridine

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Chinese Chemical Letters 2012年第10期23卷 1169-1172页

作者： Li Hua He jing Lin Chen jin yun wang Xiu Xiu Chen Xiu Zhen Tan Xing Fu Cao School of Science Jiangxi University of Science and TechnologyGanzhou 341000China School of Metallurgy and Chemical Engineering Jiangxi University of Science and TechnologyGanzhou 341000China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Two new copper（I） halide complexes bearing 2-（2-benzimidazolyl）-6-methylpyridine （Hbmp） and PPh3 ligands, Cu（Hbmp）（PPh3）X （X = Br （1）; I （2））, have been synthesized and characterized. Single-crystal X-ray structure analysis reveals that the halide ligand has a significant impact on the Cu-Npyridyl bond lengths. Complexes 1 and 2 show the solid-state emissions at ambient temperature, varying with the halide bound to the { Cu（Hbmp）（PPh3） } motif, which are perhaps best attributed to the metal-to-ligand charge-transfer （Cu（I） → Hbmp） transition mixed with some ligand-to-ligand charge-transfer （X and PPh3 → Hbmp） character.

关键词： Copper(I) complex 2-(2-Benzimidazolyl)-6-methylpyridine Crystal structure Photoluminescence

Testicular descent and fixation through a scrotal stria incision for the treatment of palpable cryptorchidism in children aged<3 years:10-year experience with 1034 cases

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Asian Journal of Andrology 2020年第6期22卷 649-652页

作者： Liu Chen Wen-Hua Huang yun-jin wang Qi-Liang Zhang Chao-Ming Zhou Xu Cui Jian-Qin Zhang Department of Pediatric Surgery Fujian Maternity and Child Health HospitalAffiliated Hospital of Fujian Medical UniversityFuzhou 350001China

This study was performed to summarize our clinical experience with testicular descent and fixation through a scrotal stria incision for the treatment of palpable cryptorchidism in *** study included 1034 children with palpable cryptorchidism from March 2009 to March 2019.A scrotal stria incision was used to perform testicular descent and ***,1020 children successfully underwent surgical testicular descent and fixation through a scrotal stria incision,and 14 patients underwent conversion to inguinal incision *** patients were discharged 1-2 days after the *** hospitalization and follow-up,55 patients developed complicationsy including 10 patients with testicular retraction,7 with poor healing of the incision,and 38 with a scrotal *** patients developed testicular atrophy,an in direct ingui nal hernia,or a *** descent and fixation through a scrotal stria incision for the treatment of palpable cryptorchidism in children is safe and feasible in well-selected *** method has the advantages of no scarring and a good cosmetic effect.

关键词： children cosmetic effect palpable cryptorchidism scrotal stria incision testicular descending fixation