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Journal of Hydrodynamics 1991年第1期3卷 1-10页

作者： Fan, Shang-yong Lu, shao-kang Acad of Naval Engineering Wuhan China

On the basis of oblique towing tests and flow visualizations of ship models, the flow pattern around a high-speed transom-stern ship, its motion attitudes (sinkage and trim) and the characteristics of hydrodynamic forces are analysed. It is concluded that the variation of ship motion attitudes, caused by ship speed, has a great influence over the coefficients of hydrodynamic forces and moments acting on the oblique running ship. Ship attitudes related to different speed and drift angles are calculated by Hess-Smith method. By distributing complex singularities over the surface of a double model and by considering separated vortex sheets in the wake at the lee side of the model, pressures and velocities of the fluid around the model may be calculated directly by solving a three-dimensional body with lift problem. The transom stern stream-lines are extended to form a virtual length. In this way, the hydrodynamic lateral forces, yaw moments and pressure distribution are calculated. The results show good agreement with those measured from model tests.

关键词： Flow of Fluids Visualization Mathematical Techniques Matrix Algebra Mechanical Variables Measurement Angles Ship Models Ships Hulls

Analysis of Thermoelastohydrodynamic Performance of Journal Misaligned Engine Main Bearings

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Chinese Journal of Mechanical Engineering 2015年第3期28卷 511-520页

作者： BI Fengrong shao kang LIU Changwen WANG Xia ZHANG Jian State Key Laboratory of Engines Tianjin University

To understand the engine main bearings＇ working condition is important in order to improve the performance of engine. However, thermal effects and thermal effect deformations of engine main bearings are rarely considered simultaneously in most studies. A typical finite element model is selected and the effect of thermoelastohydrodynamic（TEHD） reaction on engine main bearings is investigated. The calculated method of main bearing＇s thermal hydrodynamic reaction and journal misalignment effect is finite difference method, and its deformation reaction is calculated by using finite element method. The oil film pressure is solved numerically with Reynolds boundary conditions when various bearing characteristics are calculated. The whole model considers a temperature-pressure-viscosity relationship for the lubricant, surface roughness effect, and also an angular misalignment between the journal and the bearing. Numerical simulations of operation of a typical I6 diesel engine main bearing is conducted and importance of several contributing factors in mixed lubrication is discussed. The performance characteristics of journal misaligned main bearings under elastohydrodynamic（EHD） and TEHD loads of an I6 diesel engine are received, and then the journal center orbit movement, minimum oil film thickness and maximum oil film pressure of main bearings are estimated over a wide range of engine operation. The model is verified through the comparison with other present models. The TEHD performance of engine main bearings with various effects under the influences of journal misalignment is revealed, this is helpful to understand EHD and TEHD effect of misaligned engine main bearings.

关键词： main bearings journal misaligned oil film pressure Reynolds equation finite difference methods thermoelastohydrodynamic(TEHD)

Landslide prediction based on improved principal component analysis and mixed kernel function least squares support vector regression model

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Journal of Mountain Science 2021年第8期18卷 2130-2142页

作者： LI Li-min CHENG shao-kang WEN Zong-zhou School of Electronics and Information Xi’an Polytechnic UniversityXi’an710048China School of Automation Northwestern Polytechnical UniversityXi’an710072China

Landslide probability prediction plays an important role in understanding landslide information in advance and taking preventive *** factors can influence the occurrence of landslides,which is easy to have a curse of dimensionality and thus lead to reduce prediction *** the generalization ability of the model will also decline sharply when there are only small *** reduce the dimension of calculation and balance the model’s generalization and learning ability,this study proposed a landslide prediction method based on improved principal component analysis(PCA)and mixed kernel function least squares support vector regression(LSSVR)***,the traditional PCA was introduced with the idea of linear discrimination,and the dimensions of initial influencing factors were reduced from 8 to *** improved PCA can not only weight variables but also extract the original ***,combined with global and local kernel function,the mixed kernel function LSSVR model was framed to improve the generalization *** optimization algorithm(WOA)was used to optimize the ***,Root Mean Square Error(RMSE),the sum of squared errors(SSE),Mean Absolute Error(MAE),Mean Absolute Precentage Error(MAPE),and reliability were employed to verify the performance of the *** with radial basis function(RBF)LSSVR model,Elman neural network model,and fuzzy decision model,the proposed method has a smaller ***,the landslide warning level obtained from the landslide probability can also provide references for relevant decision-making departments in emergency response.

关键词： Landslide probability LSSVR Mixed kernel function Improved PCA Warning level

A ratiometric fluorescent nanoprobe based on ZIF-8@AuNCs-Tb for visual detection of 2,6-pyridinedicarboxylic acid

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Journal of Rare Earths 2022年第8期40卷 1165-1172页

作者： kang shao Siyu Wen Mengyuan Zhang Jing Wang Shiyi Ye Zaifa Pan College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014China Institute of Animal Husbandry and Veterinary Science Zhejiang Academy of Agricultural SciencesHangzhou 310002China College of Life Science Yangtze UniversityJingzhou 434023China

The rapid and sensitive detection of 2,6-pyridinedicarboxylic acid(DPA),one of the main biomarkers of Bacillus anthracis,is of great significance for the screening and diagnosing of ***,a ratiometric fluorescent nanoprobe based on zeolite imidazolate framework-8(ZIF-8)@AuNCs-Tb was constructed by embedding both gold nanoclusters(AuNCs)and terbium ions(Tb^(3+))into ZIF-8 for highresolution visual detection of *** to the aggregation induced emission enhancement(AIE)effect,AuNCs embedded in ZIF-8 emit a strong orange *** Tb^(3+)is coordinated with DPA added to the nanoprobe,it will emit a strong green fluorescence owing to the antenna *** results reveal that ZIF-8@AuNCs-Tb nanoprobe can detect DPA effectively with a good linear relationship in the range of 40-200 and 200-1000μmol/L,the limit of detection(LOD)is estimated at 1.8μmol/L(3σ/k).The proposed nanoprobe shows a remarkable selectivity for DPA and is quite easy to realize visualization based on the fluorescent color changing from orange to green,which has potential application in clinical *** feasibility of this method was verified by standard addition recovery experiments simulating the release of DPA from spores.

关键词： Terbium ions Ratiometric fluorcscent nanoprobe Visual detection Gold nanoclusters Zeolite imidazolate framework-8 Rare earths

One-step synthesis of hollow PEI-NaBiF4:Yb^3+/Er^3+upconversion nanoparticles for water-responsive luminescent probe

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Journal of Rare Earths 2020年第4期38卷 362-368页

作者： Zaifa Pan Yingting Wen Tao Wang Kai Wang Yuanjie Teng kang shao College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310000China

Novel PEI-modified NaBiF4:Yb3+/Er3+upconversion nanoparticles(UCNPs)with hollow structure were prepared by a surface modification free one-step solvothermal method and applied as a luminescent probe to determinate water content in organic ***,SEM and HRTEM results demonstrate that the obtained PEI-NaBiF4:Yb3+/Er3+UCNPs are pure hexagonal phase with uniform *** successful modification of PEI on the UCNPs surface was evidenced byζ-potential test,XPS and TG *** synthesized UCNPs are disintegrated into smaller nanoparticles in the presence of water and thus result in a surface quenching effect,which show the features of 0-100%wide range water response in various organic *** sensing performance towards real samples was validated by the water content determination in beer,rum and white ***,the luminescence intensity variation of the PEI-modified NaBiF4:Yb3+/Er3+enable the test visualization and ease of portability.

关键词： Luminescent probe Upconversion nanoparticles Water detection Organic solvents Rare earths

Source Separation of Diesel Engine Vibration Based on the Empirical Mode Decomposition and Independent Component Analysis

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Chinese Journal of Mechanical Engineering 2012年第3期25卷 557-563页

作者： DU Xianfeng LI Zhijun BI Fengrong ZHANG Junhong WANG Xia shao kang State Key Laboratory of Engines Tianjin UniversityTianjin 300072China

Vibration signals from diesel engine contain many different components mainly caused by combustion and mechanism operations,several blind source separation techniques are available for decomposing the signal into its components in the case of multichannel measurements,such as independent component analysis（ICA）.However,the source separation of vibration signal from single-channel is *** order to study the source separation from single-channel signal for the purpose of source extraction,the combination method of empirical mode decomposition（EMD） and ICA is proposed in diesel engine signal *** performance of the described methods of EMD-wavelet and EMD-ICA in vibration signal application is compared,and the results show that EMD-ICA method outperforms the other,and overcomes the drawback of ICA in the case of single-channel *** independent source signal components can be separated and identified effectively from one-channel measurement by ***,EMD-ICA improves the extraction and identification abilities of source signals from diesel engine vibration measurements.

关键词： empirical mode decomposition independent component analysis source separation single-channel signal

Advance in Antibacterial Magnesium Alloys and Surface Coatings on Magnesium Alloys:A Review

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Acta Metallurgica Sinica(English Letters) 2020年第5期33卷 615-629页

作者： Yang shao Rong-Chang Zeng Shuo-Qi Li Lan-Yue Cui Yu-Hong Zou shao-kang Guan Yu-Feng Zheng Corrosion Laboratory for Light Metals College of Materials Science and EngineeringShandong University of Science and TechnologyQingdao 266590China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China College of Chemical and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing 100871China

Magnesium(Mg)alloys as a bioabsorbable light metal have shown great clinical potential as bone replacement *** this review,the categories,progress in cutting-edge preparation technologies and antibacterial mechanisms of Mg alloys and considerable numbers of corrosion-resistant and functional coatings are *** relationship among the microstructure(grain size,intermetallic compounds),biocorrosion resistance and biocompatibility for antibacterial Mg alloys is *** challenge and outlooks of biomedical Mg alloys and coatings are proposed from an antibacterial perspective.

关键词： Magnesium alloys Antibacterial properties Coatings Degradation Biomaterial

Phase Evolution and Magnetic Properties of Sn_(1-2x)Fe_xNb_xO_2(0.45≤x≤0.50)

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Chemical Research in Chinese Universities 2010年第6期26卷 876-879页

作者： WANG Yu JIA Xiao-lin DONG Lin GUAN shao-kang School of Materials Science and Engineering Zhengzhou University Zhengzhou 450001 P. R. China

Sn1-2xFexNbxO2（0.45≤x≤0.50） samples were prepared at 1000 ℃ via a simple chemical co-precipitation *** effects of the concentrations of Sn doped on the structures and magnetic properties of the samples have been investigated.A systematic variation from monoclinic to orthorhombic FeNbO4 structure was observed with increasing Sn *** phase evolutions were observed from monoclinic structure with x=0.50 to the coexistence of monoclinic and orthorhombic structures with x=0.48,0.47,0.46,and then to orthorhombic structure with x=*** behavior was observed for all the samples,and the magnetic ordering temperatures decrease with increasing Sn concentration,which further indicated the sequence of phase *** results suggest that the incorporation of Sn can stabilize the orthorhombic FeNbO4.

关键词： FeNbO4 Sn doping Structure Magnetic behavior

Optimization of inter-helix spacing for helical piles in sand

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 936-952页

作者： kang shao Qian Su Junwei Liu Kaiwen Liu Zhipeng Xiong Tengfei Wang Key Laboratory of High-Speed Railway Engineering Ministry of Education School of Civil EngineeringSouthwest Jiaotong UniversityChengdu610031China School of Civil Engineering Qingdao University of TechnologyQingdao266033China Guangxi Communications Investment Group Co.Ltd Nanning530022China

The optimization of the inter-helix spacing is a key issue of the axial bearing capacity of helical *** this paper,based on the cavity expansion,an analytical approach considering the small-strain stiffness,strength,compressibility and stress level of sand around the helical pile was proposed to analyze the influence zone of the helices to determine the optimal inter-helix spacing in *** calculation results of the proposed method were verified using the centrifuge test data and finite element analysis for helical pile in Congleton HST95 *** were also compared with those using the Meyerhof pile foundation *** results show that the optimal inter-helix spacing based on Meyerhof pile foundation theory differs significantly from the *** range of the influence zone for the helices in sand calculated by the cavity expansion theory matches with the data from *** calculation results with the proposed method are consistent with the range of the optimal spacing ratio inferred in the centrifuge *** results based on the two-dimensional(2D)finite element model(FEM)are also basically consistent with the calculated analytical solution.

关键词： Helical pile Sand Analytical solution Cavity expansion theory Optimal inter-helix spacing

Clarifying effect of welding conditions on microstructure and mechanical properties of friction stir spot-welded DH590 automotive high-strength steel plates

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Journal of Iron and Steel Research International 2021年第2期28卷 232-243页

作者： Ya-peng Zhao Lian-feng Chen Shi-jie Zhu Yu-feng Sun shao-kang Guan School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001HenanChina Henan Key Laboratory of Advanced Magnesium Alloys Zhengzhou UniversityZhengzhou 450001HenanChina Beijing Shougang Co. Ltd.Beijing 100041China

Friction stir spot welding was successfully applied to the 1.2-mm-thick DH590 dual-phase steel plates by using a polycrystalline cubic boron nitride rotating *** welding,the rotation speed ranged from 600 to 1000 r/min and the penetration depth ranged from 0.1 to 0.3 *** the spot joints,the size of the stir zone increased with the increase in rotation speed as well as the penetration depth of the *** with the banded ferrite and martensite structure of the base metal,a mixed microstructure of ferrite and tempered martensite,refined bainite structure and coarse martensite structure were found in the heat-affected zone,thermomechanically affected zone and stir zone of the joints,*** kinds of interfacial shapes were formed between the upper and lower steel plates,and the formation of the bonded interface was dominated mainly by the penetration depth of the rotating tool rather than the rotation *** was revealed that the joints with straight interfaces showed higher shear tensile loads comparing with those with hook-like *** tensile tests showed that the maximum shear tensile load reached about 15.56 kN when the rotation speed and penetration depth were set as 800 r/min and 0.3 mm,*** specimen was fractured through plug failure mode with a total elongation of about 5.6 mm.

关键词： Friction stir spot welding DH590 dual-phase steel Microstructure Joint strength Microhardness