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Journal of Environmental Sciences 2007年第1期19卷 80-85页

作者： HU hai XIAO wen-jun YUAN Jian SHI Jian-wei CHEN Ming-xia SHANG GUAN wen-feng Research Center for Combustion and Environment Technology Shanghai Jiao Tong University. Shanghai 200030 China

Anatase TiO2 films were successfully prepared on foam nickel substrates by sol-gel technique using tetrabutyl titanate as precursor. The characteristics of the TiO2 films were investigated by XPS, XRD, FE-SEM, TEM and UV-Vis absorption spectra. The photocatalytic activities of TiO2 films were investigated by photocatalytic degradation reactions of gaseous acetaldehyde, an indoor pollutant, under ultraviolet light irradiation. It was found that Ni^2＋ doping into TiO2 films due to the foam nickel substrates resulted in the extension of absorption edges of TiO2 films from UV region to visible light region. The pre-heating for foam nickel substrates resulted in the formation of NiO layer, which prevented effectively the injection of photogenerated electrons from TiO2 films to metal nickel. The TiO2 films displayed high photocatalytic activity for the degradation of acetaldehyde, and were enhanced by calcining the substrates and coating TiO2 films repeatedly. The high activity was mainly attributed to the improvement of the characteristics of substrate surface and the increase of active sites on photocatalyst.

关键词： photocatalyst TiO2 films foam nickel sol-gel acetaldehyde degradation

Dimensionless model to determine spontaneous combustion danger zone in the longwall gob

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西安科技大学学报 2011年第6期31卷 649-654页

作者： ZHANG Xin-hai DENG jun wen Hu College of Energy Science and Engineering Xi＇ an University of Science and Technology Xi＇ an 710054 China

According to spontaneous combustion propensity,the longwall gob is divided into three zones,including heat dissipation zone,self-heating zone and the choking *** in the self-heating zone can temperature of coal rise due to *** the distribution of the "Three Zones" in gob is important for predicting and preventing spontaneous combustion in *** normal mining operations,temperature of coal is roughly *** process of mass transfer in the gob is considered to be *** on mass conservation,gas species conservation,darcy's law,Ficks law of diffusion and coal oxidation 1-grade reaction rule,governing equation for air leakage intensity and species concentration are *** critical value of coal spontaneous combustion and the size of longwall workface as basic dimension,a dimensionless steady coupled model of air flow diffusion and chemical reaction in loose coal of Fully Mechanized Top-Coal Caving Mining Workface(FMTCCMW) is *** solving the model numerically,regulation of three zones' distribution and spontaneous combustion in the gob can be *** results can be easily popularized to prediction of spontaneous combustion in other coalmines' longwall gob.

关键词： fully mechanized top-coal caving workface spontaneous combustion dimensionless model

Application of Geometric Midline Yield Criterion for Strip Drawing

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Journal of Iron and Steel Research International 2009年第6期16卷 13-16页

作者： WANG Gen-ji DU hai-jun ZHAO De-wen LIU Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

A new linear yield criterion expressed by the geometric midline of error triangle between Tresca and Twin shear stress yield loci on the π-plane in haigh-Westergaard space was introduced. The criterion was written in terms of the values of principal stress deviator and called GM yield criterion for short. Together with a Cartesian coordinate velocity field instead of the Avitzur＇s, the GM criterion was used to obtain an analytical solution for strip drawing. With a working example of the strip drawing through wedge-shaped die, the results of relative drawing stress calculated by the GM criterion were compared with those calculated by Mises＇ criterion from Avitzur formula. It indicated that the calculated results according to analytical solution were in good agreement with the numerical solution obtained from Avitzur formula.

关键词： GM yield criterion strip drawing analytical solution

Research progress of slippage characteristic and gas film stability enhancement methods on biomimetic hydrophobic surfaces

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Journal of Hydrodynamics 2024年第1期36卷 87-101页

作者： Meng-zhuo Zhang hai-bao Hu Liu-zhen Ren Lu-yao Bao jun wen Luo Xie School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China

The biomimetic hydrophobic surface is a potentially efficient underwater drag reduction method and the drag reduction mechanism of this kind of surface comes from the interfacial *** now,it is a hotspot to grasp the slippage characteristic and explore slippage enhancement *** paper not only summarizes our numerical simulation and experimental results of slippage characteristic at the solid-liquid interface(SLI)of hydrophobic surfaces(HS)and the gas-liquid interface(GLI)of superhydrophobic surfaces(SHS)in recent years,but also introduces some innovative methods that can effectively improve the gas film stability and drag reduction effect of ***,we used the molecular dynamics(MD)simulation method to figure out the effect of the solid-liquid interaction strength,the system temperature and the shear rate on the slippage of SLI,and expound their action mechanism from molecular ***,by MD and multibody dissipative particle dynamics(MDPD)method,the slippage behavior at the GLI was studied under the influence of the microstructure size and the flow driving *** proposed a new kind of hybrid slip boundary condition model to describe the slippage characteristic on *** addition,we found through experiment that a three-dimensional backflow will appear on the GLI under the interfacial adsorption of surfactants,and the backflow direction will reverse with the change of GLI ***,we put forward the wettability step structure and gas injection method to enhance the stability and drag reduction effect of the gas film on SHS.

关键词： Hydrophobic surface superhydrophobic surface interfacial slip underwater drag reduction

Phase behavior of gas condensate in porous media using real-time computed tomography scanning

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Petroleum Science 2024年第2期21卷 1032-1043页

作者： wen-Long Jing Lei Zhang Ai-Fen Li jun-Jie Zhong hai Sun Yong-Fei Yang Yu-Long Cheng jun Yao Institute of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina

The phase behavior of gas condensate in reservoir formations differs from that in pressure-volume-temperature(PVT)cells because it is influenced by porous media in the reservoir *** was used as a sample to investigate the influence of porous media on the phase behavior of the gas *** pore structure was first analyzed using computed tomography(CT)scanning,digital core technology,and a pore network *** sandstone core sample was then saturated with gas condensate for the pressure depletion *** each pressure-depletion state was stable,realtime CT scanning was performed on the *** scanning results of the sample were reconstructed into three-dimensional grayscale images,and the gas condensate and condensate liquid were segmented based on gray value discrepancy to dynamically characterize the phase behavior of the gas condensate in porous *** network models of the condensate liquid ganglia under different pressures were built to calculate the characteristic parameters,including the average radius,coordination number,and tortuosity,and to analyze the changing mechanism caused by the phase behavior change of the gas *** types of condensate liquid(clustered,branched,membranous,and droplet ganglia)were then classified by shape factor and Euler number to investigate their morphological changes dynamically and *** results show that the dew point pressure of the gas condensate in porous media is 12.7 MPa,which is 0.7 MPa higher than 12.0 MPa in PVT *** average radius,volume,and coordination number of the condensate liquid ganglia increased when the system pressure was between the dew point pressure(12.7 MPa)and the pressure for the maximum liquid dropout,Pmax(10.0 MPa),and decreased when it was below *** volume proportion of clustered ganglia was the highest,followed by branched,membranous,and droplet *** study provides crucial experimental evidence for the phase behavior chan

关键词： Gas condensate Pressure depletion Real-time micro-computed tomography scanning Distribution of condensate liquid

Permanent lining castable with low bulk density and thermal conductivity:bauxite castable for tundish obtained by adding pearlescent sand

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Journal of Iron and Steel Research International 2024年第3期31卷 634-646页

作者： Yi Wang Jian Yang Bao Wang hai-jun Zhang Juan Han Pei-yan Pei wen-long Lv Jian-an Zhou The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina Wuhan Research Institute of Metallurgical Construction MCCWuhan 430081HubeiChina

The low thermal conductivity and light mass of castables for tundish permanent linings are crucial for minimizing the heat loss of molten *** consideration of the low bulk density and thermal conductivity of pearlescent sand,the thermal insulation performance of castables was attempted to be improved by adding pearlescent *** sand was modified to prevent the strength of its porous structure from *** modification mechanism of pearlescent sand and the effect of pearlescent sand on the performance of bauxite castables were *** results suggested that the addition of the modified pearlescent sand significantly raised the apparent porosity and decreased the bulk density of bauxite *** 1000℃,the bulk density of more than 60%of the modified pearlescent sand-bauxite castable was only 2.03 g/cm^(3).The mechanical properties and thermal shock resistance of the modified pearlescent sand-bauxite castable were inferior to those of conventional bauxite castable but were adequate to meet the use conditions of casta-bles for tundish permanent *** high temperatures of 200-800℃,the thermal conductivity of more than 60%of the modified pearlescent sand-bauxite castable was smaller than that of conventional bauxite *** addition of the modified pearlescent sand can greatly reduce the thermal conductivity and bulk density of bauxite castable.

关键词： Pearlescent sand-Hydrophobic modification Bauxite castable Thermal insulation performance Mechanical property

Effect of V on high-temperature mechanical properties of Al-5Cu-1.5Ni alloy

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Journal of Iron and Steel Research International 2024年第7期31卷 1792-1810页

作者： jun-ge Cui Yong-bin Chen Xiang-zhou Fu hai-long Yang Han-zhang Wang An-min Li Li-wen Pan School of Resources Environment and MaterialsGuangxi UniversityNanning 530004GuangxiChina State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures Nanning 530004GuangxiChina Guangxi Higher Education Key Laboratory of Advanced Materials Nanning 530004GuangxiChina

The effects of V on microstructure,room temperature,and high-temperature(350℃)mechanical properties of Al-5Cu-1.5Ni alloy were *** results show that Al-5Cu-1.5Ni-xV alloys mainly compriseα-Al,Al_(2)Cu,Al_(3)(Ni,Cu)_(2),Al_(3)Ni,Al7Cu4Ni,and Al_(10)V *** addition of V can signally refineα-Al dendritic structure,which improves the mechanical properties of the as-cast alloys at room and high *** T6 heat treatment(540℃/12 h/WC+170℃/8 h/AC),α-Al,network skeleton structure Al_(3)(Ni,Cu)_(2),and Al_(10)V phases all show coarsening,while the fine nano-θ'-Al_(2)Cu precipitated from the matrix and dispersed *** introduction of V promotes the quantity of precipitatedθ'-Al_(2)Cu *** ultimate tensile strength of the heat-treated alloys at room and high temperatures is greatly improved compared to that of the as-cast *** highest high-temperature ultimate tensile strength of the alloys with V is 111.8 MPa,21.5%higher than that of the base *** analysis shows that the improvement of high-temperature mechanical properties after heat treatment is mainly due to the introduction of V,increasing the precipitated quantity of nano-θ'-Al_(2)Cu particles and improving its thermal *** dispersion strengthening effect ofθ'-Al_(2)Cu particles exceeds the weakening effect of other adverse microstructures on the mechanical properties.

关键词： Al-Cu-Ni-V alloy θ'-Al_(2)Cu phase Heat treatment Microstructure Mechanical property

Accelerating Asteroidal Period and Pole Inversion from Multiple Lightcurves Using Parallel Differential Evolution and Cellinoid Shape Model

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Research in Astronomy and Astrophysics 2024年第4期24卷 271-286页

作者： Yong-Xiong Zhang wen-Xiu Guo Xiao-Ping Lu Hua Zheng hai-Bin Zhao jun Tian Wei-Lin Wang School of Engineering Guangzhou College of Technology and BusinessGuangzhou 510850China School of Computer Science and Engineering Macao University of Science and TechnologyTaipaMacao 999078China School of Mathematics and Statistics Shaoguan UniversityShaoguan 512099China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao 999078China Key Laboratory of Planetary Sciences Purple Mountain ObservatoryCASNanjing 210023China

Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally *** paper presents a new approach that combines a simplified Cellinoid shape model with the Parallel Differential Evolution(PDE)algorithm to accelerate *** PDE algorithm is more efficient than the Differential Evolution algorithm,achieving an extraordinary speedup of 37.983 with 64 workers on multicore *** PDE algorithm accurately derives period and pole values from simulated *** analysis of real asteroid lightcurves validates the method’s reliability:in comparison with results published elsewhere,the PDE algorithm accurately recovers the rotational periods and,given adequate viewing geometries,closely matches the pole *** PDE approach converges to solutions within 20,000 iterations and under one hour,demonstrating its potential for large-scale data *** work provides a promising new tool for unveiling asteroid physical properties by overcoming key computational bottlenecks.

关键词： methods:numerical minor planets asteroids:general techniques:photometric astrom

Molecular Mechanism of Polysaccharides Extracted from Chinese Medicine Targeting Gut Microbiota for Promoting Health

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Chinese Journal of Integrative Medicine 2024年第2期30卷 171-180页

作者： ZHAO wen-xiao WANG Tong ZHANG Ya-nan CHEN Qian WANG Yuan XING Yan-qing ZHENG jun DUAN Chen-chen CHEN Lijun ZHAO hai-jun WANG Shijun School of Nursing Shandong University of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJi'nan(250355)China Shandong Co-innovation Center of Classic Traditional Chinese Medicine Formula Shandong University of Traditional Chinese MedicineJi'nan(250355)China College of Traditional Chinese Medicine Shandong University of Traditional Chinese MedicineJinan(250355)China

The accumulating evidence revealed that gut microbiota plays an important role in pathological process of disease including obesity,type 2 diabetes mellitus,heart failure,and non-alcoholic fatty liver *** extracted from Chinese medicine(CM)can not only alleviate pathological status but also promote health by anti-inflammatory,regulating immunity,lowering blood glucose and lipids,anti-cancer,and *** alterations of gut microbiota composition and metabolism pathways are the potential mechanisms of CM polysaccharides *** addition,they exert functions through gut-organ axis or play an indirect role by synergistic actions with other drugs or components mediated by gut *** review summarizes the molecular mechanisms of CM polysaccharides interacted with intestinal microbial inhabitants as potential prebiotics forpromoting health.

关键词： Chinese medicine polysaccharides gut microbiota short-chain fatty acids lipopolysaccharides gut-organaxis synergistic actions

Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,junggar Basin,NW China

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Petroleum Science 2024年第1期21卷 100-114页

作者： wen-Long Dang Gang Gao Xin-Cai You Ke-Ting Fan jun Wu De-wen Lei wen-jun He Yong Tang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China School of GeoSciences China University of Petroleum(Beijing)Beijing102249China Exploration&Development Institute Xinjiang Oil Field CompanyKaramay834000XinjiangChina

The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu *** oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu *** crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep *** migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source *** changes might alter source rock evaluations and oil-source *** on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu *** source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate *** rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped ***,biomarker composition parameters indicate a higher thermal maturity than in-situ source *** a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin *** finding reminds

关键词： Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag