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Neural Regeneration Research 2016年第6期11卷 951-956页

作者： Zhen Feng qing du Department of Rehabilitation the First Affiliated Hospital of Nanchang University

Electrical stimulation of the median nerve is a noninvasive technique that facilitates awakening from coma. In rats with traumatic brain injury-induced coma, median nerve stimulation markedly enhances prefrontal cortex expression of orexin-A and its receptor, orexin receptor 1. To further understand the mechanism underlying wakefulness mediated by electrical stimulation of the median nerve, we evaluated its effects on the expression of the N-methyl-D-aspartate receptor subunit NR1 in the prefrontal cortex in rat models of traumatic brain injury-induced coma, using immunohistochemistry and western blot assays. In rats with traumatic brain injury, NR1 expression increased with time after injury. Rats that underwent electrical stimulation of the median nerve（30 Hz, 0.5 ms, 1.0 m A for 15 minutes） showed elevated NR1 expression and greater recovery of consciousness than those without stimulation. These effects were reduced by intracerebroventricular injection of the orexin receptor 1 antagonist SB334867. Our results indicate that electrical stimulation of the median nerve promotes recovery from traumatic brain injury-induced coma by increasing prefrontal cortex NR1 expression via an orexin-A-mediated pathway.

关键词： stimulation traumatic median cortex subunit minutes NMDAR markedly antagonist aspartate

Two-Phase Flow in Porous Electrodes of Proton Exchange Membrane Fuel Cell

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Transactions of Tianjin University 2020年第3期26卷 197-207页

作者： Daokuan Jiao Kui Jiao qing du State Key Laboratory of Engines Tianjin University135 Yaguan RoadTianjin 300350China

Water management in porous electrodes bears significance due to its strong potential in determining the performance of proton exchange membrane fuel *** terms of porous electrodes,internal water distribution and removal process have extensively attracted attention in both experimental and numerical ***,the structural difference among the catalyst layer(CL),microporous layer(MPL),and gas diffusion layer(GDL)leads to significant challenges in studying the two-phase flow *** the different porosities and pore scales of the CL,MPL,and GDL,the model scales in simulating each component are *** review emphasizes the numerical simulation related to porous electrodes in the water transport process and evaluates the effectiveness and weakness of the conventional methods used during the *** limitations of existing models include the following:(i)The reconstruction of geometric models is difficult to achieve when using the real characteristics of the components;(ii)the computational domain size is limited due to massive computational loads in three-dimensional(3 D)simulations;(iii)numerical associations among 3 D models are lacking because of the separate studies for each component;(iv)the effects of vapor condensation and heat transfer on the two-phase flow are disregarded;(v)compressive deformation during assembly and vibration in road conditions should be considered in two-phase flow studies given the real operating ***,this review is aimed at critical research gaps which need further *** potential research directions are also suggested for future improvements.

关键词： PEMFC Porous electrodes Two-phase flow Water management

Chlorobenzenes in waterweeds from the Xijiang River (Guangdong section) of the Pearl River

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Journal of Environmental Sciences 2007年第10期19卷 1171-1177页

作者： du qing-ping JIA Xiao-shan HUANG Cai-na Faculty of Environmental Science and Engineering Guangdong University of Technology Guangzhou 510006 China School of Environmental Science and Engineering Sun Yat-sen University Guangzhou 510275 China

The Xijiang River is the major source of water for about 4.5 millions of urban population and 28.7 millions of rural population. The water quality is very important for the health of the rural population. The concentration and distribution of chlorobenzenes （CBs） in both water and waterweeds collected from 4 stations in the Xijiang River （Gangdong section） of the Pearl River in April and November were determined. The result showed that nearly every congener of CBs was detected. The total contents of CBs （ZCBs） in the river water ranged from 111.1 to 360.0 ng/L in April and from 151.9 to 481.7 ng/L in November, respectively. The pollution level of CBs in the water in April was higher than that in November. The contents of ZCBs in waterweeds ranged from 13.53×10^2μg/g to 38.27×10^2μg/g dry weight （dw）. There was no significant difference between April and November in waterweeds. The distribution of CBs in roots, caulis, and leaves of Vallisneria spiralis L. showed different patterns. The leaves mainly contained low-molecular-weight CBs （DCBs）, whereas the roots accumulated more PCBs and HCBs. The average lgBCFlip （bioconcentration factor） of CBs ranged from 0.64 to 3.57 in the waterweeds. The spatial distribution character of CBs in the Xijiang River was： Fengkai County 〈 Yunan County 〈 Yun＇an County 〈 Gaoyao County according to the ZCBs, and the pollution deteriorated from the upstream to the downstream of the Xijiang River. Further analysis demonstrated that the discharge of waste containing CBs may be the main source of CBs pollution in the Xijiang River .

关键词： chlorobenzenes pollution water water weeds distribution bioconcentration factor

The study on the relationship between breakup modes and gas-liquid interfaces

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Chinese Science Bulletin 2008年第18期53卷 2898-2906页

作者： du qing LIU Ning YIN Jun Internal Combustion Engine Research Institute Tianjin University Tianjin 300072 China Slate Key Laboratory of Engines Tianjin University Tianjin 300072 China

Based on the linear instability analysis, the study on the relationship between breakup modes and gas-liquid interfaces of a viscous annular liquid jet moving in two swirling gas streams has been car- ried out. From the numerical results of the dispersion equation, the relevancy of the breakup mode between an annular liquid jet and two liquid jets of limiting cases, namely the cylindrical liquid jet and hollow gas jet, as well as the effects of injecting factors on the instability of an annular liquid jet, is studied in detail. Considering the effects of inner and outer interface radii on the instability of the jet, it is proved that the para-sinuous mode mainly relates to the inner interface, whereas the para-varicose mode mainly relates to the outer interface. The results also indicate that all the forces produced by liquid jet have similar impacts on either the instability of para-sinuous mode or para-varicose mode due to the fact that they can affect both inner and outer gas-liquid interfaces. On the other hand, all the forces exerting only on the inner interface have more powerful effects on the instability of para-sinuous mode, and all the forces exerting only on the outer interface have more powerful effects on the insta- bility of para-varicose mode. That is to say, the effects of forces are weakened greatly when penetrating the liquid jet.

关键词：气液反应液体喷射不稳定性衰弱模式

Direct numerical simulation of low Reynolds number turbulent air-water transport in fuel cell flow channel

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Science Bulletin 2017年第1期62卷 31-39页

作者： Zhiqiang Niu Renfang Wang Kui Jiao qing du Yan Yin State Key Laboratory of Engines Tianjin UniversityTianjin 300072China Sunrise Power Co. Ltd.Dalian 116085China

With performance improvement of low-temperature fuel cell(FC), high reactant supply and water generation rates may induce air-water turbulence in the FC flow channel. In this research, an air-water turbulent direct numerical simulation(DNS) model is developed to simulate different droplet sizes,locations and interactions in the air-water transport processes comprehensively. It is found that a larger droplet breaks up more easily in turbulence, and a smaller droplet tends to keep lumped. The droplet at corner does not break up because it is away from channel center. The droplet interaction simulations show that the small droplets merge to form slugs, but still keep lumped in turbulence. It is suggested that two conditions need to be satisfied for droplet break up in FC flow channel, one is turbulent flow, and another is that the droplet needs to be large enough and occupy the center region of flow channel to suffer sufficient turbulence fluctuations. The DNS results illustrate some unique phenomena in turbulent flow, and show that the turbulence has significant effect on the air-water flow behavior in FC flow channel.

关键词： DNSFuel cell Turbulence Air-water flow

Efficient removal of chlorophenols from water with a magnetic reduced graphene oxide composite

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Science China Chemistry 2016年第3期59卷 350-359页

作者： Han Yan qing du Hu Yang Aimin Li Rongshi Cheng State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China

A magnetic reduced graphene oxide composite(MRGO) was successfully prepared by a simple and green method. MRGO was then used as an adsorbent and found to exhibit enhanced removal efficiency for various chlorophenols(CPs) from water compared with its precursors, graphene oxide(GO) and reduced graphene oxide. The CPs were o-chlorophenol, p-chlorophenol, 2,4-dichlorophenol, and 2,4,6-trichlorophenol. Among them, 2,4,6-trichlorophenol, which exhibited the lowest water solubility and highest molecular weight, most easily bound to MRGO. The preferential interactions between MRGO and CPs were hydrophobic interactions(?-? stacking and hydrophobic effect). This result was confirmed by the equilibrium adsorption behavior in which isotherms were all well described by Freudlich model, indicating heterogeneous and multilayer adsorption. Therefore, CP adsorption was more favored under neutral and acidic conditions, and the decreased removal efficiency of MRGO at higher p H levels was due to the improved hydrophilicity of CPs for deprotonation effect. Moreover, MRGO showed fast removal of each CP, achieving adsorption equilibrium within 10.0 min, presented efficient separation from water under an external magnetic field, and was easily regenerated using dilute Na OH aqueous solution after reaching saturated adsorption. Adsorption capacity of the regenerated MRGO had almost no loss until after five cycles. In summary, MRGO was an efficient adsorbent for the removal of various CPs and had considerable application potential in water treatment.

关键词： magnetic reduced graphene oxide composite green preparation method chlorophenol adsorption mechanism

Flame behavior, shock wave, and instantaneous thermal field generated by unconfined vapor-liquid propylene oxide/air cloud detonation

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Defence Technology（防务技术） 2023年第7期25卷 18-32页

作者： Cong-liang Ye qing-lei du Li-juan Liu Qi Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Safety Science and Emergency Management Wuhan University of TechnologyWuhanHubei430070China

Energy output and heating effects are essential for vapor-liquid fuel/air cloud detonation in the fuel-air explosive(FAE) applications or explosion accidents. The purpose of this study is to examine the dynamic large-size flame behavior, shock wave propagation law, and instantaneous thermal field generated by unconfined vapor-liquid propylene oxide(PO)/air cloud detonation. Based on computational fluid dynamics(CFD) and combustion theory, a numerical simulation is used to study the detonation process of a PO/air cloud produced by a double-event fuel-air explosive(DEFAE) of 2.16 kg. The large-scale flame behavior is characterized. The flame initially spreads radially and laterally in a wing shape. Subsequently,the developed flame increases with a larger aspect ratio. Moreover, the propagation laws of shock waves at different heights are discussed. The peak pressure of 1.3 m height level with a stepwise decline is obviously different from that of the ground with an amplitude of reversed ’N’ shape. In the vast majority of the first 6.9 m, the destructive effect of the shock wave near the ground is greater than that of the shock wave at 1.3 m height. Furthermore, the dynamic instantaneous isothermal field is *** scaling relationship of various isotherms in the instantaneous thermal field with the flame and initial cloud is summarized. The comprehensive numerical model used in this study can be applied to determine the overpressure and temperature distribution in the entire fuel/air cloud detonation field,providing guidance for assessing the extent of damage caused by DEFAE detonation.

关键词： Numerical simulation Fuel-air explosive Fuel/air cloud Flame Shock wave Thermal field

Preparation and characterization of boron-doped corn straw biochar: Fe(Ⅱ) removal equilibrium and kinetics

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Journal of Environmental Sciences 2021年第8期33卷 116-123页

作者： Long Sui Chunyu Tang qing du Ying Zhao Kui Cheng Fan Yang Joint laboratory of Northeast Agricultural University and Max Planck Institute of Colloids and Interfaces(NEAU-MPICI) Harbin 150030 School of Water Conservancy and Civil Engineering Northeast Agricultural UniversityHarbin 150030China College of Engineering Northeast Agricultural UniversityHarbin 150030China

Nowadays,iron ions as a ubiquitous heavy metal pollutant are gradually concerned and the convenient and quick removal of excessive iron ions in groundwater has become a major challenge for the safety of drinking *** this study,boron-doped biochar(B-BC)was successfully prepared at various preparation conditions with the addition of boric *** as-prepared material has a more developed pore structure and a larger specific surface area(up to 897.97 m2/g).A series of characterization results shows that boric acid effectively activates biochar,and boron atoms are successfully doped on *** with the ratio of raw materials,the pyrolysis temperature has a greater influence on the amount of boron *** on Langmuir model,the maximum adsorption capacity of 800 B-BC1:2 at25℃,40℃,55℃ are 50.02 mg/g,95.09 mg/g,132.78 mg/g,***-second-order kinetic model can better describe the adsorption process,the adsorption process is mainly chemical *** complexation,ions exchange,and co-precipitation may be the main mechanisms for Fe2+removal.

关键词： Boron-doped biochar Pyrolysis temperature Iron ions Removal mechanisms

Design and Implementation of 3D Model Database for General-Purpose 3D GIS

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Geo-Spatial Information Science 2010年第3期13卷 210-215页

作者： XU Weiping ZHU qing du Zhiqiang ZHANG Yeting State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University129 LuoyuRoad Wuhan 430079 China

To improve the reusability of three-dimensional （3D） models and simplify the complexity of natural scene reconstruction, this paper presents a 3D model database for universal 3D GIS. After the introduction of its extensible function architecture, accompanied by the conclusion of implicit spatial-temporal hierarchy of models in any reconstructed scene of 3D GIS for general purpose, several key issues are discussed in detail, such as the storage and management of 3D models and related retrieval and load method, as well as the interfaces for further on-demand development. Finally, the validity and feasibility of this model database are proved through its application in the development of 3D visualization system of railway operation.

关键词： 3D model database 3D GIS 3D modeling CAD models

Solar radio filtering algorithm based on improved long short-term memory

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Research in Astronomy and Astrophysics 2021年第4期21卷 79-92页

作者： qing-Fu du Qiao-Man Zhang Xin Li Chang-Lin Gao School of Mechanical Electrical&Information EngineeringShandong UniversityWeihai 264209China

The effective observation of burst events in solar radio research has been impeded by various interference signals,especially interference signals with a wide frequency range and high intensity,as they can partially or completely obscure the observation of burst *** processing methods that directly remove the interference signal channels and subtract the average of the interference signal channel are not suitable for processing all types of interference *** paper proposes the use of a specific kind of recurrent neural networks,called long short-term memory networks,to predict the value of the radio frequency interference signals with high intensity of the burst event in the solar radio *** predicted interference can then be removed in accordance with the principle that signals can be linearly ***,predicted value is subtracted from the data containing the burst event signals and the RFI signals(The radio frequency interference signals to be processed in this article refer to the signal of the broadcast signal that can be received in the frequency range,the signal transmitted by the mobile phone,and the signal transmitted by the sea vessel,and the like)to remove the ***,in order to reduce the error caused by the stepwise prediction in the network and further improve the prediction accuracy,this paper analyzes the characteristics of the value of the radio interference and applies the digital mapping method to convert the prediction problem into the classification problem in the time *** experimental results show that the proposed method can effectively remove the radio interference in the solar spectrum and clearly show the burst events.

关键词： Sun:radio radiation methods:data analysis techniques:image processing