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Influence of deformation path on the forming effect in a multistep flexible rolling process

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International Journal of Minerals,Metallurgy and Materials 2018年第10期25卷 1173-1180页

作者： Ying li Wen-zhi Fu Ming-zhe li Xiao-dong liu Shuo Sun Zhuo Yi Roll Forging Institute Jilin University College of materials science and engineering Jilin University

The flexible rolling process(FRP) is a novel three-dimensional(3 D) forming process that combines the multipoint and traditional rolling forming. The principle of FRP is based on thickness thinning, so the deformation path significantly impacts the forming effect. In this study, the multistep forming process with different deformation paths was introduced to improve the forming effect of FRP. For instance, with the convex surface part, three finite element models of multistep FRP(MSFRP) were established. The corresponding numerical simulations and forming experiments performed among different deformation paths showed the surface part with a longer effective forming region was obtained and the forming regions with more steps in MSFRP were smoother. Thus, the sheet-metal utilization rate was greatly improved. Moreover, the MSFRP can improve the longitudinal bending effect dramatically and thereby endowing the forming part with a better forming effect. Therefore, MSFRP is a prospective method for broad applications.

关键词： 3D surface forming multistep flexible rolling numerical simulation deformation path forming effect

Bestow metal foams with nanostructured surfaces via a convenient electrochemical method for improved device performance

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Nano Research 2016年第8期9卷 2364-2371页

作者： Yawen Zhan Shanshan Zeng Haidong Bian zhe li zhengtao Xu Jian LU Yang Yang li Center of Super-Diamond and Advanced Films (COSDAF) City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong China Department of Physics and Materials Science City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong China Department of Chemistry and Biology City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong China Department of Mechanical and Biomedical Engineering City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong China Centre for Advanced Structural Materials City University of Hong Kong Shenzhen Research Institute 8 Yuexing 1st Road ShenzhenHi-Tech Industrial Park Nanshan District Shenzhen 518000 China City University ofHong Kong Shenzhen Research Institute 8 Yuexing 1st Road Shenzhen Hi-Tech Industrial Park Nanshan District Shenzhen 518000 China

Metal foams have been intensively studied as three-dimensional （3-D） bulk mass-support for various applications because of their high conductivities and attractive mechanical properties. However, the relatively low surface area of conventional metal foams largely limits their performance in applications such as charge storage. Here, we present a convenient electrochemical method for addressing this problem using Cu foams as an example. High surface area Cu foams are fabricated in a one-pot one-step manner by repetitive electrodeposition and dealloying treatments. The obtained Cu foams exhibit greatly improved performance for different applications like surface enhanced Raman spectroscopy （SERS） substrates and 3-D bulk supercapacitor electrodes.

关键词： electrodeposition dealloying metal foams surface enhanced Ramanspectroscopy substrates supercapacitors

Temporal-spatial risk assessment of COVID-19 under the influence of urban spatial environmental parameters:The case of Shenyang city

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Building Simulation 2023年第5期16卷 683-699页

作者： Sui li zhe li Yixin Dong Tiemao Shi Shiwen Zhou Yumeng Chen Xun Wang Feifei Qin School of Architecture and Planning Shenyang Jianzhu UniversityShenyangLiaoning 110168China Institute of Ecological Urban Planning and Green Building Shenyang Jianzhu UniversityShenyangLiaoning 110168China School of Architecture Tianjin UniversityTianjin 300072China Institute of Spatial Planning and Design Shenyang Jianzhu UniversityShenyangLiaoning 110168China School of Science Shenyang Jianzhu UniversityShenyangLiaoning 110168China

Respiratory infection is the main route for the transmission of coronavirus pneumonia,and the results have shown that the urban spatial environment significantly influences the risk of *** on the Wells-Riley model of respiratory infection probability,the study determined the human respiratory-related parameters and the effective influence range;extracted urban morphological parameters,assessed the ventilation effects of different spatial environments,and,combined with population flow monitoring data,constructed a method for assessing the risk of Covid-19 respiratory infection in urban-scale grid *** the empirical study in Shenyang city,a severe cold region,urban morphological parameters,population size,background wind speed,and individual behavior patterns were used to calculate the distribution characteristics of temporal and spatial concomitant risks in urban areas grids under different *** results showed that the correlation between the risk of respiratory infection in urban public spaces and the above variables was *** exposure time had the greatest degree of influence on the probability of respiratory infection risk among the *** the same time,the change in human body spacing beyond 1 m had a minor influence on the risk of *** the urban morphological parameters,building height had the highest correlation with the risk of infection,while building density had the lowest *** actual point distribution of the epidemic in Shenyang from March to April 2022 was used to verify the evaluation *** overlap rate between medium or higher risk areas and actual cases was 78.55%.The planning strategies for epidemic prevention and control were proposed for the spatial differentiation characteristics of different risk *** research results can accurately classify the risk level of urban space and provide a scientific basis for the planning response of epidemic prevention and control and the sa

关键词： COVID-19 virus infection rate GIS data simulations urban morphological parameters analysis infection risk assessment epidemic containment planning

Measurement and correlation study of silymarin solubility in supercritical carbon dioxide with and without a cosolvent using semi-empirical models and back-propagation artificial neural networks

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Asian Journal of Pharmaceutical Sciences 2017年第5期12卷 456-463页

作者： Gang Yang zhe li Qun Shao Nianping Feng Department of Pharmaceutical Sciences Shanghai University of Traditional Chinese MedicineShanghai201203China Open Innovation University of BradfordWest YorkshireBD71DPUK

The solubility data of compounds in supercritical fluids and the correlation between the experimental solubility data and predicted solubility data are crucial to the development of supercritical technologies. In the present work, the solubility data of silymarin(SM) in both pure supercritical carbon dioxide(SCCO2) and SCCO2 with added cosolvent was measured at temperatures ranging from 308 to 338 K and pressures from 8 to 22 MPa. The experimental data were fit with three semi-empirical density-based models(Chrastil, Bartle and Mendez-Santiago and Teja models) and a back-propagation artificial neural networks(BPANN) model. Interaction parameters for the models were obtained and the percentage of average absolute relative deviation(AARD%) in each calculation was determined. The correlation results were in good agreement with the experimental data. A comparison among the four models revealed that the experimental solubility data were more fit with the BPANN model with AARDs ranging from 1.14% to 2.15% for silymarin in pure SCCO2 and with added cosolvent. The results provide fundamental data for designing the extraction of SM or the preparation of its particle using SCCO2 techniques.

关键词： Silymarin Solubility Supercritical carbon dioxide Cosolvent Artificial neural networks

In Situ Synthesis of Cuprous Oxide/Cellulose Nanofibers Gel and Antibacterial Properties

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Computers, Materials & Continua 2018年第9期56卷 517-527页

作者： Ying Hu Qinfei Ke zhe li Wanli Han Zhiyong Yan Engineering Research Center of Technical Textiles Donghua UniversityShanghai201620China Key Laboratory of Yarn Material Manufacturing and Processing of zhejiang Province Jiaxing UniversityJiaxing314001China School of Materials Science and Engineering Georgia Institute of TechnologyAtlanta30318USA

Cellulose nanofibers were synthesized by acetobacter xylinum(xylinum 1.1812).The cellulose nanofibers with 30-90 nm width constructed three-dimension network gel,which could be used as a wound dressing since it can provide moist environment to a ***,cellulose nanofibers have no antimicrobial activity to prevent wound *** achieve antimicrobial activity,the cellulose nanofibers can load cuprous oxide(Cu2O)particles on the *** cuprous oxide is a kind of safe antibacterial *** copper ions can be reduced into cuprous oxides by reducing agents such as glucose,N2H4 and sodium *** cellulose nanofibers network gel was soaked in CuSO4 solution and filled with copper *** cuprous oxide nanoparticles were in situ synthesized by glucose and embedded in cellulose nanofibers *** morphologies and structure of the composite gel were analyzed by FESEM,FTIR,WAXRD and inductively coupled plasma(ICP).The sizes of Cu2O embedded in cellulose nanofibers network are 200-500 nm *** peak at 605 cm−1 attributed to Cu(I)-O vibration of Cu2O shits to 611 cm−1 in the Cu2O/cellulose *** Cu2O/cellulose nanofibers composite reveals the obvious characteristic XRD pattern of Cu2O and the results of ICP show that the content of Cu2O in the composite is 13.1%.The antibacterial tests prove that the Cu2O/cellulose nanofibers composite has the high antibacterial activities which is higher against *** than against ***.

关键词： Cellulose nanofiber cuprous oxide in situ synthesis antibacterial

Spatiotemporal Variations of Meteorological Droughts in China During 1961–2014: An Investigation Based on Multi-Threshold Identification

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International Journal of Disaster Risk Science 2016年第1期7卷 63-76页

作者： Jun He Xiaohua Yang zhe li Xuejun Zhang Qiuhong Tang Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences School of Environment Beijing Normal University University of Chinese Academy of Sciences

As a major agricultural country, China suffers from severe meteorological drought almost every *** studies have applied a single threshold to identify the onset of drought events, which may cause problems to adequately characterize long-term patterns of *** study analyzes meteorological droughts in China based on a set of daily gridded(0.5° 9 0.5°) precipitation data from 1961 to 2014. By using a multi-threshold run theory approach to evaluate the monthly percentage of precipitation anomalies index(Pa), a drought events sequence was identified at each grid cell. The spatiotemporal variations of drought in China were further investigated based on statistics of the frequency, duration,severity, and intensity of all drought events. Analysis of the results show that China has five distinct meteorological drought-prone regions: the Huang-Huai-Hai Plain, Northeast China, Southwest China, South China coastal region,and Northwest China. Seasonal analysis further indicates that there are evident spatial variations in the seasonal contribution to regional drought. But overall, most contribution to annual drought events in China come from the winter. Decadal variation analysis suggests that most of China's water resource regions have undergone an increase in drought frequency, especially in the liaohe, Haihe, and Yellow River basins, although drought duration and severity clearly have decreased after the 1960 s.

关键词： China Meteorological drought Multi-threshold run theory method Spatiotemporal variations

Red blood cell membrane-camouflaged nanoparticles: a novel drug delivery system for antitumor application

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Acta Pharmaceutica Sinica B 2019年第4期9卷 675-689页

作者： Qing Xia Yongtai Zhang zhe li Xuefeng Hou Nianping Feng Department of Pharmaceutical Sciences Shanghai University of Traditional Chinese Medicine

Erythrocytes(red blood cells, RBCs) are the most abundant circulating cells in the blood and have been widely used in drug delivery systems(DDS) because of their features of biocompatibility,biodegradability, and long circulating half-life. Accordingly, a 'camouflage' comprised of erythrocyte membranes renders nanoparticles as a platform that combines the advantages of native erythrocyte membranes with those of nanomaterials. Following injection into the blood of animal models, the coated nanoparticles imitate RBCs and interact with the surroundings to achieve long-term circulation. In this review, the biomimetic platform of erythrocyte membrane-coated nano-cores is described with regard to various aspects, with particular focus placed on the coating mechanism, preparation methods, verification methods, and the latest anti-tumor applications. Finally, further functional modifications of the erythrocyte membranes and attempts to fuse the surface properties of multiple cell membranes are discussed,providing a foundation to stimulate extensive research into multifunctional nano-biomimetic systems.

关键词： Red blood cells Membrane Nanoparticles Drug delivery Antitumor Biomimetic nanoparticles

Interpretation and compensation of backlash error data in machine centers for intelligent predictive maintenance using ANNs

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Advances in Manufacturing 2015年第2期3卷 97-104页

作者： Ke-Sheng Wang zhe li JФrgen Braaten Quan Yu Knowledge Discovery Laboratory Department of Production and Quality EngineeringNorwegian University of Science and Technology Key Laboratory of Intelligent Manufacturing and Robotics Shanghai University

It is especially significant for a manufacturing company to select a proper maintenance policy because maintenance impacts not only on economy, reliability and availability but also on personnel safety. This article re- ports on research in the backlash error data interpretation and compensation for intelligent predictive maintenance in machine centers based on artificial neural networks （ANNs）. The backlash error, measurement system and prediction methods are analyzed in detail. The result indicates that it is possible to predict and compensate for the backlash error in both forward and backward directions in machine centers.

关键词： Backlash error Artificial neural network(ANN) Machine centers Predictive maintenance

Simulation Study of Cloud Properties Affected by Heterogeneous Nucleation Using the GRAPES＿SCM during the TWP-ICE Campaign

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Journal of Meteorological Research 2019年第4期33卷 734-746页

作者： zhe li Qijun liU Zhanshan MA Jiong CHEN Qingu JIANG National Meteorological Center China Meteorological AdministrationBeijing 100081 Numerical Weather Prediction Center of China Meteorological Administration Beijing 100081 College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875

This study used the Global/Regional Assimilation and PrEdiction System Single-Column Model(GRAPES_SCM)to simulate monsoon precipitation with deep convective cloud and associated cirrus during the Tropical Warm Pool International Cloud Experiment(TWP-ICE),especially during the active and suppressed monsoon *** cases with different heterogeneous nucleation parameterizations were simulated by using the ensemble *** simulations clearly separated the active and suppressed monsoon periods,and they reproduced the major characteristics of monsoonal cloud such as the total cloud hydrometeor mixing ratio distribution,and precipitation and radiation *** results showed that the number concentration production rate of different heterogeneous nucleation parameterizations varied substantially under the given temperature and water vapor mixing ***,ice formation and precipitation during the monsoon period were affected only slightly by the different heterogeneous nucleation *** study also captured clear competition between different ice formation processes.

关键词： liuma microphysics scheme monsoon precipitation cloud microphysics heterogeneous nucleation GRAPES_SCM