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A THREE-SEGMENT HYDRAULIC MODEL FOR ANNULAR CUTTINGS TRANSPORT WITH FOAM IN HORIZONTAL DRILLING

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Journal of Hydrodynamics 2008年第1期20卷 67-73页

作者： CheNG Rong-chao WANG Rui-he College of Petroleum Engineering China University of Petroleum（East China） Dongying 257061 China

Through mechanical analysis, an improved hydraulic model for annular cuttings transport with foam was established for horizontal drilling. Based on the two critical inclination angles, the entire well was divided into three segments. The Bagnold stress, generalized power law rheological model and modified hindered particle settling velocity in foam fluid were adopted in the model to improve the simulation accuracy. The proposed model allows more precise prediction of cuttings transport property in the whole range of well inclination angle. Model performance was examined via case study and experimental data. Simulation results given by the propulsion iteration and trial-and-error method agree well with in-situ horizontal well drilling practice for the case study, and the comparison between the model prediction and Capo’s experimental data shows satisfactory agreement.

关键词： horizontal well foam fluid drilled cuttings hydraulic model well inclination angle

Enhanced mechanical properties of Mg-3Al-1Zn alloy sheets through slope extrusion

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International Journal of Minerals,Metallurgy and Materials 2022年第7期29卷 1343-1350页

作者： Huabao Yang Yanfu Chai Bin Jiang chao he Junjie he Qingshan Yang Ming Yuan School of Mechanical and Electrical Engineering Shaoxing UniversityShaoxing 312000China Tianjin Key Laboratory of Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300072China State Key Laboratory of Mechanical Transmissions College of Materials Science and EngineeringChongqing UniversityChongqing 400044China College of Materials Science and Engineering Yunnan UniversityKunming 650091China School of Metallurgy and Material Engineering Chongqing University of Science and TechnologyChongqing 401331China

A novel extrusion approach,entitled slope extrusion(SE),was employed to manufacture AZ31(Mg-3Al-1 Zn,wt%)alloy *** microstructures,textures,and mechanical properties were investigated,compared with those of the AZ31 sheet fabricated by conventional extrusion(CE).Through the combination of finite element simulation and actual experiment,the ultimate results indicated that significant grain refinement(from 9.1 to 7.7 and 5.6μm)and strong basal texture(from 12.6 to 17.6 and 19.5 mrd)were achieved by the SE *** essence was associated with the additional introduced inclined interface in the process of SE,which could bring about more asymmetric deformation and stronger accumulated strain along the ND when compared with the process of *** a consequence,the SE sheets exhibited a higher yield strength(YS)and ultimate tensile strength(UTS)than the counterparts of the CE sheet,which was mainly assigned to the synergistic effects from grain refining and texture strengthening.

关键词： AZ31 Mg alloy sheets slope extrusion microstructure texture strength

Polarisation optics for biomedical and clinical applications:a review

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Light(Science & Applications) 2021年第11期10卷 2028-2047页

作者： chao he Honghui he Jintao Chang Binguo Chen Hui Ma Martin J.Booth Department of Engineering Science University of OxfordParks RoadOxford OX13PJUK Guangdong Engineering Center of Polarisation Imaging and Sensing Technology Tsinghua Shenzhen International Graduate SchoolTsinghua University518055 ShenzhenChina Institute of Biopharmaceutical and health Engineering Tsinghua Shenzhen International Graduate SchoolTsinghua University518055 ShenzhenChina Department of Physics Tsinghua University100084 BeijingChina Department of Biomedical Engineering Tsinghua University100084 BeijingChina

Many polarisation techniques have been harnessed for decades in biological and clinical research,each based upon measurement of the vectorial properties of light or the vectorial transformations imposed on light by *** advanced vector measurement/sensing techniques,physical interpretation methods,and approaches to analyse biomedically relevant information have been developed and *** this review,we focus mainly on summarising methodologies and applications related to tissue polarimetry,with an emphasis on the adoption of the Stokes-Mueller *** recent breakthroughs,development trends,and potential multimodal uses in conjunction with other techniques are also *** primary goal of the review is to give the reader a general overview in the use of vectorial information that can be obtained by polarisation optics for applications in biomedical and clinical research.

关键词： clinical optics breakthrough

Anchor single atom in h-BN assist NO synthesis NH_(3):a computational view

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Rare Metals 2022年第10期41卷 3456-3465页

作者： chao-Zheng he Ya-Xing Zhang Jia Wang Ling Fu Institute of Environment and Energy Catalysis Shaanxi Key Laboratory of Optoelectronic Functional Materials and DevicesSchool of Materials Science and Chemical EngineeringXi’an Technological UniversityXi’an710021China College of Resources and Environmental Engineering Tianshui Normal UniversityTianshui741001China

Synthesis of ammonia gas through environmental protection and low-cost electrocatalysis is one of the ways to solve the current human energy ***,through the study of density functional theory(DFT),a series of transition metal single atoms are embedded in the defect-containing h-BN to construct a TM@B_(2) N_(2)(TM=Ti-Zn,Nb-Ag) two-dimensional *** activation effect of these single-atom catalysts on NO molecules and the electrochemical performance of catalyzing NO reduction reaction(NORR)were *** reaction pathways are studied in detail,and competition between hydrogen proton and ammonia(NH3) oxidation with NORRs is also *** the16 transition metal atoms we studied,the intercalation of Pb atom into h-BN has the best catalytic *** reaction rate-limiting potential of NORR is only 0.55 eV,and the surface heR reaction and ammonia oxidation can be effectively *** is hoped that our research can further promote the application of h-BN in the field of catalysis and provide some guidance for experimental workers in the field of ammonia synthesis.

关键词： Density functional theory(DFT)calculations Nitric oxide reduction reaction Electrocatalytic activity Ammonia Single-atom catalysts

Characteristics of temperature fluctuation in two-dimensional turbulent Rayleigh-Bénard convection

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Chinese Physics B 2022年第1期31卷 395-402页

作者： Ming-Wei Fang Jian-chao he Zhan-chao Hu Yun Bao School of Aeronautics and Astronautics Sun Yat-sen UniversityGuangzhou 510275China

We study the characteristics of temperature fluctuation in two-dimensional turbulent Rayleigh–Benard convection in´a square cavity by direct numerical *** Rayleigh number range is 1×10^(8)≤Ra≤1×10^(13),and the Prandtl number is selected as Pr=0.7 and Pr=*** is found that the temperature fluctuation profiles with respect to Ra exhibit two different distribution *** the thermal boundary layer,the normalized fluctuationθrms/θrms,max is independent of Ra and a power law relation is identified,i.e.,θrms/θrms,max∼(z/δ)0.99±0.01,where z/δis a dimensionless distance to the boundary(δis the thickness of thermal boundary layer).Out of the boundary layer,when Ra≤5×10^(9),the profiles ofθrms/θrms,max descend,then ascend,and finally drop dramatically as z/δ*** for Ra≥1×10^(10),the profiles continuously decrease and finally overlap with each *** two different characteristics of temperature fluctuations are closely related to the formation of stable large-scale circulations and corner ***,there is a critical value of Ra indicating the transition,beyond which the fluctuation hθrmsiV has a power law dependence on Ra,given by hθrmsiV∼Ra−0.14±0.01.

关键词： Rayleigh-Benard temperature fluctuation distribution patterns critical value

Two interannual variability modes of the Northwestern Pacific Subtropical Anticyclone in boreal summer

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Science China Earth Sciences 2013年第7期56卷 1254-1265页

作者： he chao ZHOU TianJun ZOU LiWei ZHANG LiXia The State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Using the reanalysis data and 20th century simulation of coupled model FGOALS_gl developed by LASG/IAP, we identified two distinct interannual modes of Northwestern Pacific Subtropical Anticyclone （NWPAC） by performing Empirical Orthogonal Function （EOF） analysis on 850 hPa wind field over the northwestern Pacific in summer. Based on the associated anoma- lous equatorial zonal wind, these two modes are termed as ＂Equatorial Easterly related Mode＂（EEM） and ＂Equatorial Westerly related Mode＂（EWM）, respectively. The formation mechanisms of these two modes are similar, whereas the maintenance mechanisms, dominant periods, and the relationships with ENSO are different. The EEM is associated with E1 Nifio decaying phase, with the anomalous anticyclone established in the preceding winter and persisted into summer through local positive air-sea feedback. By enhancing equatorial upwelling of subsurface cold water, EEM favors the transition of ENSO from E1 Nifio to La Nifia. The EWM is accompanied by the E1 Nifio events with long persistence, with the anomalous anticyclone formed in spring and strengthened in summer due to the warm Sea Surface Temperature anomalies （SSTA） forcing from the equatorial central-eastern Pacific. The model well reproduces the spatial patterns of these two modes, but fails to simulate the percentage variance accounted for by the two modes. In the NCEP reanalysis （model result）, EEM （EWM） appears as the first mode, which accounts for 35.6% （68.2%） of the total variance.

关键词： Northwestern Pacific Subtropical Anticyclone interannual variability mode equatorial easterly related mode equato-rial westerly related mode ENSO

Synthesis and Crystal Structure of 2-(4’-Methylphenoxy)-5,8,9-trimethyl-3-phenyl Thieno[3′,2′:5,6]pyrido[4,3-d]pyrimidin-4-(3H)-one Hydrochloride

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Chinese Journal of Structural Chemistry 2006年第5期25卷 577-581页

作者： LIU Jian-chao he Hong-Wu DING Ming-Wu College of Chemistry Central China Normal University Wuhan 430079 China

The title compound 2-（4＇-methylphenoxy）-5,8,9-trimethyl-3-phenyl thieno[3＇,2＇：5,6] pyrido[4,3-d]pyrimidin-4（3H）-one hydrochloride （C26H23Cl4N3O2S, Mr = 583.33） has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 14.8442（ 11 ）, b = 11.5131 （8）, c = 17.2010（13） A, β = 113.7250（10）°, V = 2691.3（3） ,A^3, Z = 4, Dc = 1.440 g/cm^3, S = 1.094,μ = 0.547 mm^-1, F（000） = 1200, the final R = 0.0571 and wR = 0.1458. X-ray analysis reveals that the title compound combines with a molecule of dichloromethane by an intramolecular hydrogen bond. The thienopyridine ring is almost coplanar, and the dihedral angle between the thiophene plane and the pyridine plane is 0.6°.

关键词： thieno[3',2':5,6]pyrido[4,3-d]pyrimidin-4(3H)-one,triphenylphosphine iminophosphorane crystal structure

Technical measures to achieve a cleaner production mode for recycled paper mills

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Frontiers of Environmental Science & Engineering 2010年第4期4卷 466-474页

作者： chao he Zhaolin GU Shucheng YANG Jidong LIANG Weina DAI Yanling he School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710028China

China’s paper production reached 79.8×10^(6) t in 2008 and ranked number one in the *** of its high consumption of water,energy and materials and its serious pollution,the present processes are not likely to be *** alternative,the closed Water Loop-Papermaking Integration(WLPI)method,is put forward in this *** WLPI method can be realized in a recycled paper mill by adding technologies and using recycled *** industrial case studies have shown that a large quantity of water,energy and materials can be saved,and the quantity of waste sludge and wastewater discharge was minimized by using the WLPI *** design of the water reuse system,control of calcium hardness,water recycling and minimal waste sludge are *** technology plays an important role in the WLPI method to lower cost,energy use and *** the brown paper and coated white board production,zeroeffluent discharge can be *** water consumption is only 1-2m^(3)·t^(-1).For the paper mills with deinking and bleaching processes,about 10 m^(3)·t^(-1) of fresh water and a similar amount of effluent discharge are *** saving using anaerobic technology is 70%when recycled water is used in comparison with the conventional activated sludge *** sludge can be decreased to about 5%of the initial process due to reuse of the waste sludge and the lower bio-sludge production of the anaerobic process.

关键词： water reuse zero discharge anaerobic treatment recycled paper cleaner production

High NO_2/NO_X emissions downstream of the catalytic diesel particulate filter:An influencing factor study

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Journal of Environmental Sciences 2015年第9期27卷 55-61页

作者： chao he Jiaqiang Li Zhilei Ma Jianwei Tan Longqing Zhao School of Mechanical and Traffic Engineering Southwest Forestry University National Lab of Auto Performance and Emission Test Beijing Institute of Technology

Diesel vehicles are responsible for most of the traffic-related nitrogen oxide（NO x） emissions,including nitric oxide（NO） and nitrogen dioxide（NO2）. The use of after-treatment devices increases the risk of high NO2/NO x emissions from diesel engines. In order to investigate the factors influencing NO2/NO x emissions, an emission experiment was carried out on a high pressure common-rail, turbocharged diesel engine with a catalytic diesel particulate filter（CDPF）. NO2 was measured by a non-dispersive ultraviolet analyzer with raw exhaust sampling. The experimental results show that the NO2/NO x ratios downstream of the CDPF range around 20%–83%, which are significantly higher than those upstream of the CDPF. The exhaust temperature is a decisive factor influencing the NO2/NO x emissions. The maximum NO2/NO x emission appears at the exhaust temperature of 350°C. The space velocity,engine-out PM/NO x ratio（mass based） and CO conversion ratio are secondary factors. At a constant exhaust temperature, the NO2/NO x emissions decreased with increasing space velocity and engine-out PM/NO x ratio. When the CO conversion ratios range from 80% to 90%,the NO2/NO x emissions remain at a high level.

关键词： Diesel engine Nitrogen dioxide Diesel particulate filter Exhaust temperature Space velocity