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Journal of Rare Earths 2021年第2期39卷 160-166页

作者： Zhifeng Shang Dongtao Zhang Zhihong Xie Yunqiao Wang Muhammad Haseeb Pengbiao Qiao Weiqiang Liu ming yue College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

The evolution of the microstructure,microchemistry and magnetic properties of the Sm(CobalFe_(0.28)-CuyZrx)_(7.6)magnets with different Zr and Cu contents was *** is found that the coercivity of the Sm(Co,Fe,Cu,Zr)_(z)magnets is sensitive to Zr *** deficiency of Zr content causes heterogeneity of Cu and Fe distributions,while an excessive Zr content leads to the formation of a SmCoZr impurity *** cellular structure and distribution of Cu *** between the cell boundary phase and cell pha se are destroyed by inappropriate Zr content,which results in a reduction of *** Cu concentration difference between the cell boundary phase and cell phase increases with increasing Cu *** coercivity of the Sm(CobalFe_(0.28)CuyZ_(r0.02))_(7.6)magnets increases from 10.4 to 25.4 kOe for y=0.05 and y=***,the excess of Cu element destroys the cell boundary phase and enlarges the cell size,resulting in a significant decrease of squareness and energy *** optimum performance(remanence of 11.4 kG,coercivity of 25.4 kOe,maximum magnetic ene rgy product of 30.4 MGOe)was obtained for the Sm(Co_(0.63)Fe_(0.28)Cu_(0.07)Zr_(0.02))_(7.6)magnet.

关键词： Sm(CoFeCuZr)_(z)permanent magnets Cu Zr Microstructure Magnetic properties Composition distribution

Sensitivity of the Impact Toughness and Microstructure of 15CrNi3MoV Steel Under Different Quenching Rates

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Acta Metallurgica Sinica(English Letters) 2023年第10期36卷 1735-1748页

作者： Bing Wang Hong-Lin Zhang Bin Xu Hai-Yang Jiang ming-yue Sun Dian-Zhong Li Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The sensitivities of the mechanical properties and microstructure of 15CrNi3MoV alloy steel under different quenching rates were investigated in the present *** subjection to quenching with four different cooling rates(water cooling,forced air cooling,static air cooling and furnace cooling)followed by tempering,the microstructure was characterized by scanning electron microscopy(SEM),electron back-scattered diffraction(EBSD),and transmission electron microscopy(TEM);and the low-temperature(−20°C)impact toughness was *** results showed that the tempered microstructure and mechanical properties had high sensitivity to the quenching *** a decrease in the quenching rate,the low-temperature impact energy of tempered specimens decreased with increasing ***,the fracture morphology changed from completely ductile to *** addition,as the quenching cooling rate decreased,the as-quenched matrix changed from a lathy to a polygonal structure with the presence of carbides and martensite-austenite(M-A)constituents,and the effective grain size *** martensite with dispersed fine carbides was found in the tempered water cooling specimen,and tempered bainite with a polygonal structure containing large carbides and rare incomplete undecomposed M-A constituents was found in the tempered forced air cooling,static air cooling and furnace cooling *** small effective grain size and fine carbides contributed to the good temperature impact toughness of the tempered water cooling specimens.

关键词： Alloy steel Quenching cooling rate Impact toughness Martensite-austenite(M-A)constituents Carbides

Diesel molecular composition and blending modeling based on SUBEM framework

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Petroleum Science 2022年第2期19卷 839-847页

作者： yue-ming Guan Dong Guan Cheng Zhang Sheng-Hua Yuan Guang-Qing Cai Lin-Zhou Zhang State Key Laboratory of Heavy Oil Processing Petroleum Molecular Engineering Center(PMEC)China University of PetroleumBeijing102249China SINOPEC Dalian Research Institute of Petroleum and Petrochemicals SINOPECDalian116045LiaoningChina

Diesel molecular compositional model has important application for diesel quality prediction,blending,and molecular-level process model *** this paper,different types of diesel molecular compositional and blending models were constructed based on the SU-BEM *** than 1500 representative molecules were selected to form the molecular structure *** probability density functions(PDFs)combination was determined by experimental data and experience.A quadratic optimization strategy combining genetic algorithm with local optimization algorithm was adopted to improve the accuracy of the compositional *** model results show good agreement with the experimental *** diesel blending model was constructed at the molecular-level based on the above diesel compositional *** properties of the blending model accord with the experimental *** is proved that the compositional models and blending model constructed have high accuracy and strong prediction capability,and are applicable to the industrial process.

关键词： Molecular compositional model Molecular blending model SU-BEM Framework Diesel

THREE-DIMENSIONAL REGULARITIES OF DISTRIBUTION OF AIR-INLET CHARACTERISTIC VELOCITY IN NATURAL-DRAFT WET COOLING TOWER

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Journal of Hydrodynamics 2008年第3期20卷 323-330页

作者： WANG Kai SUN Feng-zhong ZHAO Yuan-bin GAO ming SHI yue-tao School of Energy and Power Engineering Shandong University Jinan 250061 China

A model for heat and mass transfer in a natural-draft wet cooling tower was established. Numerical simulation with the κ-ε turbulent model was conducted. Distribution rules of air inlet aerodynamic field were studied. Field experiments were done in a cooling tower in power plant, and the test data was compared with the related results. The definition of characteristic air velocity was proposed and its influencing factors, such as the cross-wind velocity and circumferential angle, were quantitatively studied. It can be used to evaluate the performance of cooling tower and to calculate the ventilation quantity and resistance of air inlet. It is also a theoretical basis for cooling tower design and performance optimization.

关键词： cooling tower flow field numerical simulation air inlet

Significant role of nanoscale Bi-rich phase in optimizing thermoelectric performance of Mg3Sb2

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Chinese Physics B 2020年第3期29卷 405-410页

作者： Yang Wang Xin Zhang Yan-Qin Liu Jiu-Xing Zhang ming yue Key Laboratory of Advanced Functional Materials Ministry of EducationCollege of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124China School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China

Mg3Sb1.5Bi0.5-based alloys have received much attention,and current reports on this system mainly focus on the modulation of ***,there lacks the explanation for the choice of Mg3Sb1.5Bi0.5 as *** in this work,the thermoelectric properties of Mg3Sb2-xBix(0.4≤x≤0.55)compounds are systematically investigated by using the first principles calculation combined with *** calculated results show that the band gap decreases after Bi has been substituted for Sb site,which makes the thermal activation *** maximum figure of merit(ZT)is 0.27 at 773 K,which is attributed to the ultra-low thermal conductivity 0.53 W·m-1·K-1 for x=*** large mass difference between Bi and Sb atoms,the lattice distortion induced by substituting Bi for Sb,and the nanoscale Bi-rich particles distributed on the matrix are responsible for the reduction of thermal *** introduction of Bi into Mg3Sb2-based materials plays a vital role in regulating the transport performance of thermoelectric materials.

关键词： first principles calculations nanoscale Bi-rich phase Mg3Sb2 thermoelectric performance

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Liveness detection of occluded face based on dual-modality convolutional neural network

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The Journal of China Universities of Posts and Telecommunications 2021年第4期28卷 1-12页

作者： ming yue Li Wenmin Xu Siya Gao Lifang Zhang Hua Shao Sujie Yang Huifeng State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China State Grid Hebei Information and Telecommunication Branch Shijiazhuang 050013China

Facial recognition has become the most common identity authentication technologies. However, problems such as uneven light and occluded faces have increased the hardness of liveness detection. Nevertheless, there are a few pieces of research on face liveness detection under occlusion conditions. This paper designs a face recognition technique suitable for different degrees of facial occlusion, which employs the facial datasets of near-infrared(NIR) images and visible(VIS) light images to examine the single-modality detection accuracy rate(experimental control group) and the corresponding high-dimensional features through the residual network(ResNet). Based on the idea of data fusion, we propose two feature fusion methods. The two methods extract and fuse the data of one and two convolutional layers from two single-modality detectors respectively. The fusion of high-dimensional features apply a new ResNet to get the dual-modality detection accuracy. And then, a new ResNet is applied to test the accuracy of dual-modality detection. The experimental results show that the dual-modality face liveness detection model improves face live detection accuracy and robustness compared with the single-modality. The fusion of two-layer features from the single-modality detector can also improve face detection accuracy by utilizing the above-mentioned dual-modality detector, and it doesn’t increase the algorithm’s complexity.

关键词： face deception face occlusion near-infrared image residual network feature fusion

Tillage force and disturbance characteristics of different geometric-shaped subsoilers via DEM

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Advances in Manufacturing 2020年第3期8卷 392-404页

作者： Jin Tong Xiao-Hu Jiang yue-ming Wang Yun-Hai Ma Jun-Wei Li Ji-Yu Sun Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchun130022People’s Republic of China College of Biology and Agricultural Engineering Jilin UniversityChangchun130022People’s Republic of China College of Mechanical and Electrical Engineering Shihezi UniversityShihezi832000XinjiangPeople’s Republic of China

With the increased use of agricultural machinery in field operations,soil compaction has become increasingly severe,and the plough pan has become *** is an excellent way to address this ***,it is limited by high energy consumption,which is closely related to tillage *** investigate the effect of the geometric shape of shanks and tines on tillage force and soil disturbance in loam,a layered soil model in accordance with the actual conditions was established and five different subsoilers were simulated via discrete element *** results indicated that the shank impacted soil disturbance and tine impacted tillage *** draft force of curved shank and chisel tine was 8%less than that of the straight shank and sweep *** straight shank and sweep tine produced a larger furrow profile and a higher furrow *** subsoiler with curved shank and chisel tine(C-C)exhibited the lowest specific resistance(12.87,17.52,19.46 and 21.18 kN/m^2 in the 30,35,40 and 45 cm tillage depth,respectively)considering the draft force and soil disturbance ***,these results will facilitate in the selection of a suitable subsoiler and design of new subsoilers with lower energy consumption requirements for loam areas worldwide.

关键词： Subsoiler Discrete element method(DEM) Tillage force Soil disturbance Soil compaction

FORECAST OF WATER TEMPERATURE IN RESERVOIR BASED ON ANALYTICAL SOLUTION

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Journal of Hydrodynamics 2008年第4期20卷 507-513页

作者： JI Shun-wen ZHU yue-ming QIANG Sheng ZENG Deng-feng College of Water Conservancy and Hydroelectric Engineering Hohai University Nanjing 210098 China Water Power Plant of Sanhe Shangyoujiang Ganzhou 341212 China

The water temperature in reservoirs is difficult to be predicted by numerical simulations. In this article, a statistical model of forecasting the water temperature was proposed. In this model, the 3-D thermal conduction-diffusion equations were converted into a system consisting of 2-D equations with the Fourier expansion and some hypotheses. Then the statistical model of forecasting the water temperature was developed based on the analytical solution to the 2-D thermal equations. The~ simplified statistical model can elucidate the main physical mechanism of the temperature variation much more clearly than the numerical simulation with the Navier-Stokes equations. Finally, with the presented statistical model, the distribution of water temperature in the Shangyoujiang reservoir was determined.

关键词： water temperature quasi 3-D statistical model thermal conduction-diffusion equation analytical solution regression analysis factor of radiation

Experimental investigation on the enhanced oil recovery efficiency of polymeric surfactant: Matching relationship with core and emulsification ability

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Petroleum Science 2023年第1期20卷 619-635页

作者： Xin Chen Yi-Qiang Li Zhe-Yu Liu Japan Trivedi Wen-Bin Gao ming-yue Sui State Key Laboratory of Oil and Gas Resources and Exploration School of Petroleum EngineeringChina University of Petroleum(Beijing)Beijing 102249China Faculty of Engineering-Civil and Environmental Engineering University of AlbertaEdmontonAlberta T6G 2R3Canada Institute of Rock and Soil Mechanics Chinese Academic of SciencesWuhanHubei 430071China PetroChina Changqing Oilfield Co Research Institute of Oilfield Exploration and Development XianShaanxi 710018China

The polymeric surfactant can be used as an efficient agent for enhanced oil recovery(EOR)because of its large bulk viscosity and good interfacial ***,there is a sparse understanding of its matching relationship with reservoirs and emulsification occurrence conditions,which may affect its migration and EOR *** intermolecular association molecule polymeric surfactant(IAM)was synthesized by micellar polymerization and characterized with 1 H NMR,FTIR,and *** matching relationship between IAM and reservoirs was evaluated by comparing the viscosity retention rate of effluent in the core flow ***,the effect of the matching relationship on EOR in the heterogeneous reservoir was clarified with parallel core displacement experiments by considering different flow abilities of IAM in the high-permeability *** occurrence conditions of in-situ emulsification of IAM were evaluated via oil-water co-injection experiments under the different injection rates and oil-water *** visualization displacement was carried out to compare the micro EOR mechanisms of different chemical *** results show that IAM features thickening,shearing resistance,viscoelasticity,thermal stability,and interfacial *** matching relationship between cores and IAM could be divided as hardly injected,flow limited,and flow smoothly,corresponding to the viscosity retention ratio of80%,*** could gain better EOR efficiency(17.69%)when its matching relationship to the high permeability layer was“flow limited”.The defined mixture capillary number shows that only when it is greater than 1×10^(3),the in-situ emulsions can be *** to HPAM,IAM could reduce IFT and form vortices to more effectively displace film and corner remaining oils by stripping and peeling off crude *** formed emulsion accumulated at the pore throat could further increase flow resistance,which benefits swept area enlargemen

关键词： Migration Matching relationship Viscosity retention ratio Emulsion EOR

Interfacial Oxides Evolution of High-Speed Steel Joints by Hot-Compression Bonding

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Acta Metallurgica Sinica(English Letters) 2022年第11期35卷 1837-1848页

作者： Wei-Feng Liu Bi-Jun Xie ming-yue Sun Bin Xu Yan-Fei Cao Dian-Zhong Li Shenyang National Laboratory for Materials Science Instituteof Metal ResearchChineseAcademyof SciencesShenyang 110016China School of Materials Scienceand Engineering University of Science and Technology of ChinaShenyang 110016China

The interfacial oxidation behavior of Cr_(4)Mo_(4) V high-speed steel(HSS)joints undergoing hot-compression bonding was investigated by using optical microscopy(OM),scanning electron microscopy(SEM),and transmission electron microscopy(TEM).In the heating and holding processes,dispersed rod-like and granularδ-Al_(2)O_(3) oxides were formed at the interface and in the matrix near the interface due to the selective oxidation and internal oxidation of Al,while irregular Si-Al-O compounds and spheroidal SiO_(2) particles were formed at the *** the post-holding treatment,SiO_(2) oxides and Si-Al-O compounds were dissolved into the matrix,andδ-Al_(2)O_(3) oxides were transformed into nanoscaleα-Al_(2)O_(3) particles,which did not deteriorate the mechanical properties of the *** formation and migration of newly-formed grain boundaries by plastic deformation and post-holding treatment were the main mechanism for interface *** tensile test results showed that the strength of the healed joints was comparable to that of the base material,and the in-situ tensile observations proved that the fracture was initiated at the grain boundary of the matrix rather than at the *** clarification of interfacial oxides and microstructure is essential for the application of hot-compression bonding of HSSs.

关键词： Hot-compression bonding High-speed steel Interfacial oxides Interface healing Mechanical properties