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FINITE ELEMENT ANALYSIS OF LAMINAR FLOW AND HEAT TRANSFER IN A BUNDLE OF CYLINDERS

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Journal of Hydrodynamics 2000年第4期12卷 99-108页

作者： wang yan-xing Zhao Hong Lu Xi-yun Zhuang Li-xian Department of Modern Mechanics University of Science and Technology of ChinaHefeiAnhui 230026P.R.China

Two-dimensional Navier-Stokes equations and energy equation governing incompressible laminar flow past a bundle of cylinders were numerically solved by using the finite element method. The velocity correction method was used for time advancement, and spatial discretization was carried out with the Galerkin weighted residual method. Viscous flows past the cylinder banks arranged in in-line cylinder bundles and staggered cylinder bundles, coupled with heat transfer, were investigated for pitch-diameter ratios of 1.5 and 2.0 and the Reynolds numbers from 50 to 500. Flow structures and heat transfer behavior were discussed. The results obtained agree well with available numerical data.

关键词： finite element method velocity correction method heat transfer bundle of cylinders

Resilient performance of self-centering hybrid rocking walls with curved interface under pseudo-static loading

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 65-85页

作者： Su xing yan Shi Sun Xianglei wang Tao School of Civil Engineering Shenyang Jianzhu UniversityShenyang 110168China PetroChina East China Design Institute Co. Ltd.Qingdao 266000China Qingdao Country Garden Bolin Real Estate Co. Ltd.Qingdao 266100China

Frame and rocking wall(FRW)structures have excellent resilient performance during ***,the concrete at interfacial corners of rocking walls(RWs)is easily crushed due to local extreme compression during the rocking *** innovative RW with a curved interface is proposed to prevent interfacial corners from producing local damage,enhancing its earthquake resilient performance(ERP).The precast wall panel with a curved interface is assembled into an integral self-centering hybrid rocking wall(SCRW)by two post-tensioned unbonded prestressed ***,two ordinary energy dissipation steel rebars and two shear reinforcements are arranged to increase the energy dissipation capacity and lateral *** SCRW specimens and one monolithic reinforced concrete(RC)shear wall(SW)were tested under pseudo-static loading to compare the ERPs of the proposed SCRW and the SW,focusing on studying the effect of the curved interface on the *** key resilient performance of rocking effects,failure modes,and hysteretic properties of the SCRW were *** results show that nonlinear deformations of the SCRW are concentrated along the interface between the SCRW and the foundation,avoiding damage within the *** restoring force provided by the prestressed tendons can effectively realize self-centering capacity with small residual deformation,and the resilient performance of the SCRW is better than that of monolithic *** addition,the curved interface of the SCRW makes the rocking center change and move inward,partially relieving the stress concentration and crush of *** rocking range of the rocking center is about 41.4%of the width of the SCRW.

关键词： self-centering hybrid rocking wall(SCRW) monolithic shear wall(SW) earthquake resilient performance(ERP) curved interface rocking center

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沙南凹陷新生代断裂发育特征及控藏作用

科学技术与工程 2024年第10期24卷 4056-4069页

作者：张正涛王兴艳潘晓丽殷亮亮张国坤中国石油长庆油田公司勘探开发研究院西安710018 低渗透油气田勘探开发国家工程实验室西安710018 中国石油长庆工程设计有限公司西安710001 中国石油长庆油田公司第一采气厂西安710021 中海石油(中国)有限公司天津分公司天津300452

为明确沙南凹陷新生代断裂活动特征以及对油气富集的控制作用,利用高精度三维地震资料及钻井资料,对研究区主要断裂的几何学特征、运动学特征开展研究,并对断裂活动对烃源岩、储层、圈闭及油气运移的控制作用进行了探讨。结果认为:研究... 详细信息

为明确沙南凹陷新生代断裂活动特征以及对油气富集的控制作用,利用高精度三维地震资料及钻井资料,对研究区主要断裂的几何学特征、运动学特征开展研究,并对断裂活动对烃源岩、储层、圈闭及油气运移的控制作用进行了探讨。结果认为:研究区断裂可划分为三级及上、下两套断裂系统,孔店组~沙三段沉积期、东营组沉积期是断裂活动高峰期;高活动速率主要同沉积断层下降盘为优质烃源岩发育区,凹陷北侧不同类型断层边界决定了多种类型砂体发育模式,断裂作用控制了构造及岩性圈闭的形成,断裂及断裂砂体耦合是研究区主要的油气运移通道;发育凹陷内部中央隆起区南北两侧“断控”双通道近源成藏、凹陷北侧陡坡带“断-砂耦合”阶梯状网毯输导远源成藏、凹陷斜坡下部“断控”前缘砂体源内成藏3种断裂控藏模式;凹陷北侧深层岩性圈闭、凹陷北侧陡坡带中浅部构造圈闭是后续有利勘探方向。

关键词：断裂特征断裂体系断裂控藏新生代沙南凹陷

FINITE ELEMENT ANALYSIS OF THE FLOW INDUCED BY ROTATING BLADES IN AN INCOMPRESSIBLE VISCOUS FLUID

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Journal of Hydrodynamics 2002年第2期14卷 36-40页

作者： wang, yan-xing yang, Guo-Wei Lu, Xi-Yun Zhuang, Li-Xian Dept. of Mech. and Mech. Eng. Univ. of Sci. and Technol. of China Hefei 230026 China

Aerodynamic loads on a multi-bladed helicopter rotor in hovering flight were calculated by solving the three-dimensional incompressible Navier-Stokes equations. The rotor wake effects were accounted by the correction of local geometric angle of attack according to a free-wake modeling in addition to an empirical modification for the tip flow effect. The validity and efficiency of the present method were verified by the comparisons between numerical results and experimental data.

关键词： Aerodynamic loads Finite element method Helicopter rotors Navier Stokes equations Three dimensional Turbomachine blades Wakes

LPCS Ni-Zn-Al_(2)O_(3) Intermediate Layer Enhanced SPS NiCr-Cr_(3)C_(2) Coating with Higher Corrosion and Wear Resistances

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 188-195页

作者：白杨 LI yan xing Lukuo LI Xiangbo wang Zhenhua State Key Laboratory of Marine Coatings Marine Chemical Research Institute Co.Ltd.Qingdao 266071China College of Mechanical and Electrical Engineering University of China Petroleum(East China)Qingdao 266580China Science and Technology on Marine Corrosion and Protection Laboratory Luoyang Ship Materials Research InstituteQingdao 266101China

The double-layer NiCr-Cr_(3)C_(2)/Ni-Zn-Al_(2)O_(3) coatings with sufficient corrosion and wear resistance were prepared on low carbon steel *** intermediate layers Ni-Zn-Al_(2)O_(3) were fabricated by using low-pressure cold spray (LPCS) method to improve the salt fog corrosion resistance properties of the supersonic plasma spray (SPS) NiCr-Cr_(3)C_(2) *** friction and wear performance for the double-layer and single-layer NiCr-Cr_(3)C_(2) coatings were carried out by line-contact reciprocating sliding,*** with the coating surface analysis techniques,the effect of the salt fog corrosion on the tribological properties of the double-layer coatings was *** results showed that the double-layer coatings exhibited better wear resistance than that of the single-layer coatings,due to the better corrosion resistance of the intermediate layer;the wear mass losses of the double-layer coatings was reduced by 70%than that of the single layer coatings and the wear mechanism of coatings after salt fog corrosion conditions is mainly corrosion wear.

关键词： low-pressure cold spray NiCr-Cr_(3)C_(2)coating wear behavior salt fog corrosion

Somatic Embryogenesis and Plant Regeneration from Two Recalcitrant Genotypes of Gossypium hirsutum L.

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Agricultural Sciences in China 2006年第5期5卷 323-329页

作者： wang yan-xia wang xing-fen MA Zhi-ying ZHANG Gui-yin HAN Gai-ying Hebei Agricultural University/Key Laboratory of Crop Germplasm Resources of Hebei Baoding 071001 P.R. China

An improved protocol has been developed for somatic embryogenesis and plant regeneration of recalcitrant cotton cultivars. High callus frequencies and embryogenic tissue were developed in MSB medium supplemented with gradient concentrations of KT and 2,4-D, their concentration decreasing from 0.1 to 0.01 mg·L^-1. Somatic embryos were successfully incubated in 1/2 macronutrient MSB suspension supplemented with 0.5 g· L^-1 glutamine and 0.5 g·L^-1 asparagine. Decrease in macronutrient concentration of MSB significantly alleviated browning and was beneficial to suspension cells. Transformation of somatic embryos into plants was induced in MSB medium supplemented with 3% sucrose, 0.5 g·L^-1 glutamine, 0.5 g·L^-1 asparagine, and 6.0 g·L^-1 agar. The effect of sucrose as carbohydrate was better than that of glucose for plant germination. Using this protocol, regenerated plantlets from the CCRI521 and Zhongzhi86-6 reached to as much as 19.6 and 18.5% somatic embryos, respectively.

关键词： Gossypium hirsutum L. recalcitrant genotypes plant regeneration somatic embryogenesis effect of macronutrients suspension culture

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苏东南区致密气压裂井EUR评价方法研究

内蒙古石油化工 2024年第4期50卷 116-120页

作者：代恒黄刚张延斌王兴艳马琪田婉玲中国石油长庆油田分公司第一采气厂陕西西安710016

单井最终可采储层(Estimated Ultimate Reserve,EUR)评价是致密油气藏动态分析的重要工作,对气井合理产量制定、井网的部署和调整具有重要意义。在现有单井EUR评价方法适用性分析的基础上,筛选出了适用于致密砂岩气藏压裂井EUR评价方法... 详细信息

单井最终可采储层(Estimated Ultimate Reserve,EUR)评价是致密油气藏动态分析的重要工作,对气井合理产量制定、井网的部署和调整具有重要意义。在现有单井EUR评价方法适用性分析的基础上,筛选出了适用于致密砂岩气藏压裂井EUR评价方法。基于苏东南区实例井分析了不同方法在气井不同生产阶段的适用性。研究结果表明:苏东南区致密砂岩气藏单井EUR评价时,生产早期推荐产量不稳定分析法,生产中期推荐产量不稳定分析法、物质平衡法,生产后期推荐产量不稳定分析法、产量递减分析法。

关键词：苏东南致密气压裂井最终可采量

Evaluating the tumor stratification with a lysosomal pH sensitive-probe by fluorescence lifetime imaging

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Chinese Chemical Letters 2024年第3期35卷 262-267页

作者： Jun yan xing Liang Qian Zhang Luolin wang Weiying Lin Guangxi Key Laboratory of Electrochemical Energy Materials Institute of Optical Materials and Chemical BiologySchool of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China

Owing to the anaerobic metabolism in the tumor,abundant acidic metabolites are produced and accumulated in the ***,the cells in different tumor layers are directly linked to the pH ***,due to the lack of robust tools,the high-efficient evaluation of the acidic micro-environment of tumor stratification faces the challenge of accurate *** designed a new pH sensitive fluorescent lifetime probe target to *** we expected,the fluorescence lifetime of PLN possesses a good linear fit to the pH value,which could detect the pH change at a single lysosome level in real time,and then evaluate the different acidity of tumor *** probe PLN is successfully used to evaluate the tumor stratification by fluorescence lifetime imaging microscopy(FLIM)for the first time,which is of great significance in the preoperative diagnosis of clinical tumor treatment or evaluation of drug delivery effect.

关键词： FLIM pH Fluorescence imaging Lysosome Tumor imaging

Recent progress in CdS-based S-scheme photocatalysts

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Journal of Materials Science & Technology 2024年第4期171卷 162-184页

作者： Yajing Ren Yunfeng Li Guixu Pan Ning wang yan xing Zhenyi Zhang College of Environmental and Chemical Engineering Xi’an Polytechnic UniversityXi’an 710048China Jilin Provincial Key Laboratory of Advanced Energy Materials Department of ChemistryNortheast Normal UniversityChangchun 130024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Photocatalytic technology with sunlight as driving force can convert solar energy into other energy sources for storage and further *** sulfide(CdS),as a typical reducing semiconductor of metal sulfides,represents an interesting research hotspot in photocatalysis due to its suitable bandgap(2.4 eV)for utilizing visible light and strong reducing ability for inducing surface catalytic ***,the photocatalytic performance of CdS is still limited by its fast carrier recombination and serious *** far,CdS semiconductor has been widely developed as a typical reducing photocatalyst in constructing novel S-scheme heterojunction to overcome the above *** this review,the de-sign concepts,basic principles,and charge transfer characteristics of CdS-based S-scheme heterojunction photocatalysts have been comprehensively *** advanced and effective characterization methods for studying the mechanism of CdS-based S-scheme heterojunction are analyzed in ***-thermore,we also summarize the typical applications of CdS-based S-scheme heterojunctions for water splitting,CO_(2) reduction,pollutant degradation,***,according to the current investigation sta-tus,some drawbacks in the current synthetic strategy,mechanism exploration,and application prospect of CdS-based S-scheme heterojunction are proposed,which need to be addressed by further expansion and innovative research.

关键词： Photocatalysis CdS semiconductor Heterojunction S-scheme Metal sulfide