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The excluded-volume effect in microscopic pedestrian simulations

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Chinese Physics B 2012年第1期21卷 539-548页

作者： Guo Ren-yong Guo xi College of Computer Science Inner Mongolia UniversityHohhot 010021China School of Public Administration Inner Mongolia UniversityHohhot 010021China

We propose a pedestrian position update rule, which is added to a microscopic pedestrian model to avoid pedestrian overlap. In the rule, the step size of a pedestrian moving in a selected direction at each update is in inverse proportion to the repulsive actions imposed by other pedestrians moving in a direction with an exponential rate. The positions of the pedestrians are then updated in each small time interval. In this way, a barrier between the pedestrians can be generated, and after updating their positions the pedestrians do not overlap with each other. The modified model is compared to the original model through a simulation of the evacuation process of pedestrians in a closed area. The simulation results indicate that the modified model is superior to the original model in several aspects.

关键词： pedestrian model excluded-volume effect discrete dynamic system

Translocation of Polymer Chains Through a Channel with Complex Geometries

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Chinese Journal of Chemical Physics 2008年第6期21卷 555-559页

作者： Zhi-yong Yang Lin-xi Zhang Jun Cheng Department of Physics Wenzhou University Wenzhou 325027 China

The elastic behavior of a single chain transporting through complex channel which can be seen as the combination of three different channels （left channel, middle channel, and right channel, respectively） is investigated using the new pruned-enriched Rosenbluth method with importance sampling. The elastic force during the translocation process is calculated. At the entrance into the middle channel, there is the first plateau in the curve of the elastic force f （f〉0） versus x, here x represents the position of the first monomer along the x-axis direction. When the first monomer moves to a certain position, a second plateau is observed with the elastic force f〈0, which represents spontaneous translocation. The free energy difference between the subchain in the right channel and the subchain in the left channel may drive the transloeation. The influence of chain length and width of the left and right channels on the translocation process are also investigated. From the simulation results, more detailed explanations for the reason why the component translocation time is not the same for different channels can be presented.

关键词： Elastic behavior nPERMis Polymer translocation

Probing the interaction between asphaltene-wax and its effects on the crystallization behavior of waxes in heavy oil via molecular dynamics simulation

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Petroleum Science 2024年第4期21卷 2839-2848页

作者： yong Hu xi Lu Hai-Bo wang Ji-Chao Fang Yi-Ning Wu JianFang Sun SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China Shandong Key Laboratory of Oilfield Chemistry School of Petroleum EngineeringChina University of Petroleum(East China)Qingdao266580ShandongChina

High content of asphaltenes and waxes leads to the high pour point and the poor flowability of heavy oil,which is adverse to its efficient development and its transportation in *** the interaction mechanism between asphaltene-wax is crucial to solve these problems,but it is still *** this paper,molecular dynamics simulation was used to investigate the interaction between asphaltenewax and its effects on the crystallization behavior of waxes in heavy *** show that molecules in pure wax are arranged in a paralleled *** wax molecules in heavy oil,which are close to the surface of asphaltene aggregates,are bent and arranged *** the mass fraction of asphaltenes in asphaltene-wax system(ω_(asp))is 0-25 wt%,the attraction among wax molecules decreases and the bend degree of wax molecules increases with the increase ofω_(asp).Theω_(asp)increases from 0 to 25 wt%,and the attraction between asphaltene-wax is stronger than that among *** causes that the wax precipitation point changes from 353 to 333 *** theω_(asp)increases to 50 wt%,wax molecules are more dispersed owing to the steric hindrance of asphaltene aggregates,and the interaction among wax molecules transforms from attraction to *** causes that the ordered crystal structure of waxes can't be formed at normal ***,the asphaltene,with the higher molecular weight or the more hetero atoms,has more obvious inhibition to the formation of wax ***,resins also have an obvious inhibition on the wax crystal due to the formation of asphalteneresin aggregates with a larger *** results reveal the interaction mechanism between asphaltene-wax,and provide useful guidelines for the development of heavy oil.

关键词： Heavy oil Interaction mechanism Asphaltenes Waxes Molecular dynamics

In Vivo and In Vitro Anti-inflammatory Effects of Ethanol Fraction from Periploca forrestii Schltr.

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Chinese Journal of Integrative Medicine 2017年第7期23卷 528-534页

作者： DONG Li ZHANG Yun wang xia DONG yong-xi ZHENG Lin LI yong-jun NI Jing-man Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical SciencesLanzhou University Engineering Research Center for the Development and Application of Ethnic Medicine and Chinese Medicine (Ministry of Education) Guizhou Medical University

Objective：To determine the anti-inflammatory effects of an ethanol fraction of Periploca forrestii Schltr.（EFPF） and to investigate the potential mechanisms underlying in vivo and in vitro models. Methods：The antiinflammatory effects of EFPF were evaluated using the xylene-induced mouse ear edema and carrageenan-induced rat paw edema models in vivo. In vitro, RAW264.7 cells were exposed to 0–800 μg/m L EFPF and the cell viability was determined by 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay. Then cells were treated with different concentrations of EFPF（100–400 μg/m L） and stimulated with lipopolysaccharide（LPS, 1 μg/m L） for 24 h. The supernatant was analyzed for nitric oxide（NO） using the Griess reagent, and the levels of inflammatory mediators and cytokines were determined using enzyme-linked immunosorbent assays for prostaglandin E2（PGE2）, tumor necrosis factor α（TNF-α）, interleukin（IL） 6, and IL-10. The protein expressions of inducible NO synthase（i NOS）, cyclooxygenase-2（COX-2）, nuclear factor κB（NF-κB）, and mitogen-activated protein kinases（MAPKs） including extracellular signal-regulated kinase（ERK）, c-Jun N-terminal kinase（JNK）, and p38 MAPK were examined by Western blot. Results：Compared with the control group, EFPF significantly reduced mouse ear edema and rat paw edema rate（P〈0.05 or P〈0.01）. Compared with the LPS group, EFPF significantly inhibited the LPS-stimulated production of NO, PGE2, TNF-α and IL-6（P〈0.05 or P〈0.01）, and increased the IL-10 production（P〈0.05）. EFPF also significantly inhibited LPS-induced protein expressions of i NOS and COX-2, suppressed the phosphorylation and degradation of inhibitor of NF-κB-α, decreased p65 level, and inhibited the phosphorylation of p38, ERK1/2 and JNK（P〈0.05 or P〈0.01）. Conclusion：EFPF exerted anti-inflammatory effect by reducing protein expressions of i NOS and COX-2 and the production of the inflammation factors, including TNF-α, IL-6, NO and PGE2, mainly through inhibition of L

关键词： Periploca forresti Schltr anti-inflammatory effect mitogen-activated protein kinase nuclear factor κB

Conductive Film with Flexible and Stretchable Capability for Sensor Application and Stealth Information Transmission

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Chinese Journal of Polymer Science 2021年第2期39卷 164-173,I0005页

作者： Yi-Fei Shan Kun Yang Zhi-xi Li xiao-xiao wang Hao Li yong-Yan Cui College of Chemical Engineering and Materials Science Tianjin University of Science and TechnologyTianjin 300457China Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072China

Flexible and wearable strain sensors for human-computer interaction,health monitoring,and soft robotics have drawn widespread attention to promising applications in the next generation of artificial intelligence ***,conventional semiconductor sensors are difficult to meet the requirements of flexibility and ***,we reported a kind of novel and simple sensor based on layer-by-layer(LBL)*** nanotubes(CNTs)layer provides high ductility and stability in the process of tension sensing,while silver layer provides low initial resistance and fast reflecting in the process of tension *** method ensures the uniformity of the conductive *** sensor has superior sheet resistance of 9.44Ω/sq.,high elongation at break of 104%.For sensing capability,the sensor has wide reflecting range of 60%,high gauge factor(GF)of 1000 up to 60%strain,fast reflecting time of 165 *** reliability and stability have also been *** is also worth mentioning that the entire process does not require any expensive equipments,complicated processes or harsh experimental *** above features provide an idea for large-scale application of flexible stretchable sensors.

关键词： Strain sensor Flexibility Silver films Carbon nanotubes Human motion monitoring

Microstructure,Mechanical Properties,and Corrosion Behavior of Mg-Al-Ca Alloy Prepared by Friction Stir Processing

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Acta Metallurgica Sinica(English Letters) 2022年第5期35卷 703-713页

作者： Wen wang Shan-yong Chen Ke Qiao Pai Peng Peng Han Bing Wu Chen-xi wang Jia wang Yu-Hao wang Kuai-She wang School of Metallurgical Engineering National and Local Joint Engineering Research Center for Functional Materials ProcessingXi’an University of Architecture and TechnologyXi’an710055China

Friction stir processing(FSP)was used to modify the microstructure and improve the mechanical properties and corrosion resistance of an Mg-Al-Ca *** results demonstrated that,after FSP,the grain size of the Mg-Al-Ca alloy was decreased from 13.3 to 6.7μ***,the Al_(8)Mn_(5) phase was broken and dispersed,and its amount was *** yield strength and ultimate tensile strength of the Mg-Al-Ca alloy were increased by 17.0%and 10.1%,respectively,due to the combination of fine grain,second phase,and orientation strengthening,while the elongation was slightly *** immersion and electrochemical corrosion rates in 3.5 wt%NaCl solution decreased by 18.4%and 37.5%,respectively,which contributed to grain ***,the stress corrosion cracking(SCC)resistance of the modified Mg-Al-Ca alloy decreased significantly,which was mainly due to the filiform corrosion induced by the Al_(8)Mn_(5) *** was mainly controlled by anodic dissolution,while the cathodic hydrogen evolution accelerated the SCC process.

关键词： Friction stir processing Mg-Al-Ca alloy Second phase Mechanical properties Stress corrosion cracking

Soil Wetting Patterns and Water Distribution as Affected by Irrigation for Uncropped Ridges and Furrows

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Pedosphere 2015年第3期25卷 468-477页

作者： ZHANG yong-yong ZHAO xi-Ning WU Pu-Te Linze Inland River Basin Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Key Laboratory of Eco-hydrology of Inland River Basin Chinese Academy of Sciences Institute of Water Saving Agriculture in Arid regions of China Northwest A&F University

The ridge-furrow tillage combined with furrow irrigation is being more widely applied and has been shown to be effective in the Loess Plateau of China. Accurate characterization of water infiltration behavior under ridge-furrow irrigation could provide guidelines and criteria for future irrigation system design and operation. Our objective was to investigate soil water behavior during ponding infiltration in a cross-sectional ridge-furrow configuration. Soil water movement within three different soil textures was tested by tracking the spatial and temporal soil water content(SWC) variations in a soil chamber. The two-dimensional transient flow initially transferred rapidly, but gradually decreased with elapsed infiltration time, approaching a stable flow after 90 min. A technical parameter equation incorporating the Philip equation was developed using the water balance method to accurately predict total applied water volume(TAWV). The wetting patterns moved outward in an elliptical shape. The wetted lateral and downward distances fitted using equations accounted for capillary and gravitational driving forces in variably wetted soil media. Increasing initial SWC resulted in an increase in wetted soil volume, which can also be caused by decreasing bulk density in a homogeneous soil. Higher water level produced greater wetted lateral distance and more irrigation uniformity. The wetted lateral distance was almost identical to the wetted depth in silty clay loam soil; hence ridge-furrow irrigation should be implemented in such finer-textured soils. The wetted soil volume differed markedly among different soil textures(hydraulic properties), demonstrating that these properties can largely determine soil water spreading patterns and distribution.

关键词： infiltration ridge-furrow tillage soil texture soil water content technical parameter equation wetted soil volume

Effects of enteral nutrition with different energy supplies on metabolic changes and organ damage in burned rats

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Burns & Trauma 2022年第1期10卷 103-115页

作者： yong-Jun Yang Sen Su yong Zhang Dan Wu Chao wang Yan Wei xi Peng Clinical Medical Research Center Southwest HospitalThird Military Medical University(Army Medical University)Chongqing China Institute of Burn Research State Key Laboratory of TraumaBurns and Combined InjurySouthwest HospitalThird Military Medical University(Army Medical University)Chongqing China Shriners Burns Hospital Massachusetts General HospitalHarvard Medical SchoolBostonMA 02114USA

Background:Enteral nutrition(EN)is an important treatment for burn ***,severe gastrointestinal damage caused by major burns often leads to EN *** EN solves this problem basically,but how to transition from trophic EN to standard EN smoothly is still a challenge in burn clinical *** aim of this study is to investigate the effects of EN with different energy supplies on metabolic changes,organ damage and prognosis in burned ***:Different feeding regimens were designed based on the continuous monitoring of resting energy expenditure in ***-two Sprague-Dawley rats were randomly divided into a normal control group,burn+50%REE group,burn+75%REE group and burn+100%REE *** the end of a nutritional treatment cycle(14th day),nuclear magnetic resonance spectroscopy,blood biochemistry analysis and quantification of subscab bacteria were performed to explore the differences in metabolic changes,degrees of organ damage and prognoses between the ***:Sixteen metabolites involving seven metabolic pathways were identified from the different energy supply *** burn injury,resting energy consumption and body weight loss increased ***,weight loss was inversely related to energy *** greatest changes in the degree of organ damage,the level of plasma proteins,lipids and endotoxins,as well as the quantification of subscab bacteria were observed in the 50%REE group,followed by the 75 and 100%***:Achieving an early balance between energy supply and expenditure is conducive to mitigating metabolic disorders and improving prognosis after burn injury.

关键词： Burn Energy supply Enteral nutrition Hypermetabolic Organ damage

Interactions between Intersecting Pedestrian and Vehicle Flows on Roads

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Chinese Physics Letters 2011年第11期28卷 282-285页

作者： GUO Ren-yong GUO xi College of Computer Science Inner Mongolia UniversityHohhot 010021 School of Public Administration Inner Mongolia UniversityHohhot 010021

The crossing of vehicle flow by pedestrians at either signalized crosswalks or locations away from crosswalks is studied using a car-following *** model process is constructed,and two safe criterions deciding whether pedestrians begin to cross a road and a rule stopping vehicles at a signal intersection are *** results indicate that the relations of both vehicles’and pedestrians’delays to the width of pedestrian arrival interval are nonlinear;careful pedestrians unnecessarily spend more time to cross a road than aggressive ones;pedestrians crossing near a traffic signal have more influence on their and vehicles’*** pedestrians are permitted to cross a road using the gaps between slow vehicles,their delay may increase.

关键词： necessarily spend delay