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Hot deformation behavior of an antibacterial Co–29Cr–6Mo–1.8Cu alloy and its effect on mechanical property and corrosion resistance

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journal of Materials Science & Technology 2018年第3期34卷 523-533页

作者： Erlin Zhang yang ge Gaowu Qin Key Lab.for Anisotropy and Texture of Materials Education Ministry of China School of Materials Science and Engineering Northeastern University

In order to optimize the deformation processing, the hot deformation behavior of Co-Cr-Mo-Cu （here- after named as Co-Cu） alloy was studied in this paper at a deformation temperature range of 950-1150 ℃ and a strain rate range of 0.008-5 s^-1. Based on the true stress-true strain curves, a constitutive equation in hyperbolic sin function was established and a hot processing map was drawn. It was found that the flow stress of the Co-Cu alloy increased with the increase of the strain rate and decreased with the increase of the deforming temperature. The hot processing map indicated that there were two unstable regions and one well-processing region. The microstructure, the hardness distribution and the electro- chemical properties of the hot deformed sample were investigated in order to reveal the influence of the hot deformation. Microstructure observation indicated that the grain size increased with the increase of the deformation temperature but decreased with the increase of the strain rate. High temperature and low strain rate promoted the crystallization process but increased the grain size, which results in a reduction in the hardness. The hot deformation at high temperature （1100-1150 ℃） would reduce the corrosion resistance slightly. The final optimized deformation process was： a deformation temperature from 1050to 1100 ℃, and a strain rate from 0.008 to 0.2 s^-1, where a completely recrystallized and homogeneously distributed microstructure would be obtained.

关键词： Cu containing Co based alloy Flow behaviors Constitutive equation Hot processing map Recrystallization Co-Cr-Mo alloy Biomedical application

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Optimization for ASP flooding based on adaptive rationalized Haar function approximation

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Chinese journal of Chemical Engineering 2018年第8期26卷 1758-1765页

作者： yulei ge Shurong Li Xiaodong Zhang College of Information and Control Engineering China University of Petroleum (East China) Automation School Beijing University of Posts and Telecommunications

This paper presents an adaptive rationalized Haar function approximation method to obtain the optimal injection strategy for alkali-surfactant-polymer(ASP) flooding. In this process, the non-uniform control vector parameterization is introduced to convert original problem into a multistage optimization problem, in which a new normalized time variable is adopted on the combination of the subinterval length. Then the rationalized Haar function approximation method, in which an auxiliary function is introduced to dispose path constraints, is used to transform the multistage problem into a nonlinear programming. Furthermore, an adaptive strategy proposed on the basis of errors is adopted to regulate the order of Haar function vectors. Finally, the nonlinear programming for ASP flooding is solved by sequential quadratic programming. To illustrate the performance of proposed method,the experimental comparison method and control vector parameterization(CVP) method are introduced to optimize the original problem directly. By contrastive analysis of results, the accuracy and efficiency of proposed method are confirmed.

关键词： Alkali-surfactant-polymer flooding Optimization Enhanced oil recovery Mathematical modeling Rationalized Haar function approximation Adaptive strategy

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Analysis of swirling flow effects on the characteristics of unsteady hot-streak migration

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Chinese journal of Aeronautics 2016年第6期29卷 1469-1476页

作者： Wang jingyu ge Ning Sheng Chunhua Nanjing University of Aeronautics and Astronautics Nanjing 210016China Sun yat-Sen University Guangzhou 510275China The University of Toledo OH 43606USA

The temperature of flow at the combustor exit is inherently non-uniform and the hot fluid is called hot-streak. An in-house CFD software, NUAA-Turbo, was used to carry out 3D unsteady simulations on the PW-Esingle-stage high-pressure turbine. The hot-streak effect based on real stator and combustor counts was approximately evaluated by the contraction/dilatation method on the interface. The unsteady attenuation and migration process of hot-streaks in the turbine passage were well captured. The general performance parameters for different circumferential positions of hot-streaks were relatively consistent. Then, the influences of hot-streaks on blade surface temperature were investigated by comparing results under hot-streak and uniform inflow conditions. Unsteady simulations with combined inlet hot-streak and swirling flow show that the core of a hot-streak migrates to the tip under the influence of a positive swirl, while the phenomenon is just opposite with a negative swirl. Therefore, the heat transfer environment of rotor blades shows great differences with different directions of inlet swirl.

关键词： High pressure turbine Hot-streak Interface contraction/dilatation Swirling flow Unsteady flow

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Pt-based intermetallic compound catalysts for the oxygen reduction reaction:From problems to recent developments

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journal of Energy Chemistry 2024年第12期99卷 302-324页

作者： Heyuan Tian Xian Wang jiawei ge Hao Wan Wei Ma Guanqun Xie junjie ge School of Environment and Civil Engineering Dongguan University of TechnologyDongguan 523808GuangdongChina School of Chemistry and Materials Science Key Laboratory of Precision and Intelligent ChemistryUniversity of Science and Technology of ChinaHefei 230026AnhuiChina State Grid Anhui Electric Power Research Institute Hefei 230601AnhuiChina

Proton exchange membrane fuel cells(PEMFCs)are promising next-generation energy conversion devices with advantages including high energy conversion efficiency,low noise,and environmental *** the PEMFC cathode,the oxygen reduction reaction(ORR)relies heavily on Pt-based catalysts,where PtM_(x)(M stands for transition metal)intermetallic compounds(IMCs)are considered the best choice to enhance the catalytic ***,problems such as inadequate catalytic activity,high cost,and insufficient durability,*** hamper its *** optimizations of the catalyst structure,the improvements in the preparation process,and the understanding of the reaction mechanism are of great *** developments of cathodic oxygen reduction catalysts for PEMFCs will also focus on improving the catalytic activity of intermetallic compound nanoparticles,the utilization rate,and the durability of *** the particle size and particle/carrier interaction remain key issues for future *** catalyst reaction mechanism,the surface changes of the nanoparticles of Pt(111)face before and after the catalytic reaction,and the targeted regulation of the adsorption strength between the IMCs and oxygen-containing intermediates adjusted by transition metals need to be investigated more specifically and *** the application level,the expression of catalyst properties in the catalyst membrane electrode and reactor are the keys to the performance of ***,researches on PEMFCs are still systematic *** paper summarized the recent process toward the optimization of catalyst preparation,the exploration of new catalysts,and the new understanding of the *** the reference to the development of PEMFCs,future research can start from the existing problems,solve the shortcomings of the catalyst,and promote the practical application of PEMFCs.

关键词： Oxygen reduction reaction Platinum PEMFCs Intermetallic compound

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Raman spectroscopy of diesel and gasoline engine-out soot using different laser power

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journal of Environmental Sciences 2019年第5期31卷 74-80页

作者： Haiwen ge Zhipeng ye Rui He Department of Mechanical Engineering Texas Tech University Department of Electrical and Computer Engineering Texas Tech University

We studied engine-out soot samples collected from a heavy-duty direct-injection diesel engine and port-fuel injection gasoline spark-ignition engine. The two types of soot samples were characterized using Raman spectroscopy with different laser powers. A Matlab program using least-square-method with trust-region-reflective algorithm was developed for curve fitting. A DOE(design of experiments) method was used to avoid local convergence. The method was used for two-band fitting and three-band fitting. The fitting results were used to determine the intensity ratio of D(for "Defect" or "Disorder") and G(for"Graphite") Raman bands. It is found that high laser power may cause oxidation of soot sample, which gives higher D/G intensity ratio. Diesel soot has consistently higher amorphous/graphitic carbon ratio, and thus higher oxidation reactivity, compared to gasoline soot, which is reflected by the higher D/G intensity ratio in Raman spectra measured under the same laser power.

关键词： Raman spectroscopy Diesel engine Gasoline engine Soot emission Particulate matter

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Acid-catalyzed heterogeneous reaction of 3-methyl-2-buten-1-ol with hydrogen peroxide

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journal of Environmental Sciences 2015年第5期27卷 89-97页

作者： Qifan Liu Weigang Wang Maofa ge Beijing National Laboratory for Molecular Sciences (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of Chemistry Chinese Academy of Sciences

Acid-catalyzed heterogeneous oxidation with hydrogen peroxide（H2O2） has been suggested to be a potential pathway for secondary organic aerosol（SOA） formation from isoprene and its oxidation products. However, knowledge of the chemical mechanism and kinetics for this process is still incomplete. 3-Methyl-2-buten-1-ol（MBO321）, an aliphatic alcohol structurally similar to isoprene, is emitted by pine forests and widely used in the manufacturing industries. Herein the uptake of MBO321 into H2SO4-H2O2mixed solution was investigated using a flow-tube reactor coupled to a mass spectrometer. The reactive uptake coefficients（γ） were acquired for the first time and were found to increase rapidly with increasing acid concentration. Corresponding aqueous-phase reactions were performed to further study the mechanism of this acid-catalyzed reaction. MBO321 could convert to 2-methyl-3-buten-2-ol（MBO232） and yield isoprene in acidic media. Organic hydroperoxides（ROOHs） were found to be generated through the acid-catalyzed route,which could undergo a rearrangement reaction and result in the formation of acetone and acetaldehyde. Organosulfates, which have been proposed to be SOA tracer compounds in the atmosphere, were also produced during the oxidation process. These results suggest that the heterogeneous acid-catalyzed reaction of MBO321 with H2O2 may contribute to SOA mass under certain atmospheric conditions.

关键词： Gas-liquid interaction Uptake coefficients Organic hydroperoxide Organosulfate Secondary organic aerosol

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Tool wear during high speed turning in situ TiC_p/TiB_w hybrid reinforced Ti-6Al-4V matrix composite

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Chinese journal of Aeronautics 2016年第5期29卷 1425-1435页

作者： ge yingfei Xu jiuhua Huan Haixiang School of Mechanical Engineering Nanjing Institute of Technology College of Mechanical & Electrical Engineering Nanjing University of Aeronautics & Astronautics

Chipping, adhesive wear, abrasive wear and crater wear are prevalent for both the polycrystalline diamond （PCD） and the carbide tools during high speed turning of TiCp/TiBw hybrid reinforced Ti-6Al-4V （TC4） matrix composite （TMCs）. The combined effects of abrasive wear and diffusion wear caused the big crater on PCD and carbide tool rake face. Compared to the PCD, bigger size of crater was found on the carbide tool due to much higher cutting temperature and the violent chemical reaction between the Ti element in the workpiece and the WC in the tool. However, the marks of the abrasive wear looked much slighter or even could not be observed on the carbide tool especially when low levels of cutting parameters were used, which attributes to much lower hardness and smaller size of WC combined with more significant chemical degradation of carbide. When cutting TC4 using PCD tool, notch wear was the most significant wear pattern which was not found when cutting the TMCs. However, chipping, adhesive wear and crater wear were much milder when compared to the cutting of titanium matrix composite. Due to the absence of abrasive wear when cutting TC4, the generated titanium carbide on the PCD protected the tool from fast wear, which caused that the tool life for TC4 was 6-10 times longer than that for TMCs.

关键词： Carbide tool High speed cutting PCD tool Titanium matrix composite Tool wear Turning

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Simultaneous heterotrophic nitrification and aerobic denitrification at high initial phenol concentration by isolated bacterium Diaphorobacter sp. PD-7

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Chinese journal of Chemical Engineering 2015年第5期23卷 835-841页

作者： Qilong ge Xiuping yue Guoying Wang School of Environmental Science and Engineering Taiyuan University of Technology

A strain capable of phenol degradation, hetemtrophic nitrification and aerobic denitrification was isolated from activated sludge of coking-plant wastewater ponds under aerobic condition. Based on its morphology, physiology, biochemical analysis and phylogenetic characteristics, the isolate was identified as Diaphorobacter sp. PD-7. Biodegradation tests of phenol showed that the maximum phenol degradation occurred at the late phase of exponential growth stages, with 1400 mg·L^-1 phenol completely degraded within 85 h. Diaphorobacter sp. PD-7 accumulated a vast quantity of phenol hydroxylase in this physiological phase, ensuring that the cells quickly utilize phenol as a sole carbon and energy source. The kinetic behavior ofDiaphorobacter sp. PD-7 in batch cultures was investigated over a wide range of initial phenol concentrations （0-1400mg·L^-1） by using the Haldane model, which adequately describes the dynamic behavior of phenol biodegradation by strain Diaphombacter sp. PD-7. At initial phenol concentration of 1400mg· L^-l, batch experiments （0.25 L flask） of nitrogen removal under aerobic condition gave almost entirely removal of 120.69mg· L^- 1 ammonium nitrogen within 75 h, while nitrate nitrogen removal reached 91% within 65 h. Moreover, hydroxylamine oxidase, periplasmic nitrate reductase and nitrite reductase were successfully expressed in the isolate.

关键词： Diaphorobacter sp.Phenol biodegradation Kinetics Heterotrophic nitrification Aerobic denitrification Enzyme activity

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Adaptive fuze-warhead coordination method based on BP artificial neural network

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Defence Technology（防务技术） 2023年第11期29卷 117-133页

作者： Peng Hou yang Pei yu-xue ge School of Aeronautics Northwestern Polytechnical UniversityXi'an710072ShaanxiChina

The appropriate fuze-warhead coordination method is important to improve the damage efficiency of air defense missiles against aircraft targets. In this paper, an adaptive fuze-warhead coordination method based on the Back Propagation Artificial Neural Network(BP-ANN) is proposed, which uses the parameters of missile-target intersection to adaptively calculate the initiation delay. The damage probabilities at different radial locations along the same shot line of a given intersection situation are calculated, so as to determine the optimal detonation position. On this basis, the BP-ANN model is used to describe the complex and highly nonlinear relationship between different intersection parameters and the corresponding optimal detonating point position. In the actual terminal engagement process, the fuze initiation delay is quickly determined by the constructed BP-ANN model combined with the missiletarget intersection parameters. The method is validated in the case of the single-shot damage probability evaluation. Comparing with other fuze-warhead coordination methods, the proposed method can produce higher single-shot damage probability under various intersection conditions, while the fuzewarhead coordination effect is less influenced by the location of the aim point.

关键词： Aircraft vulnerability Fuze-warhead coordination BP artificial neural network Damage probability Initiation delay

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Natural radioactive environment of urban soils in Shihezi, China

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Nuclear Science and Techniques 2009年第6期20卷 335-339页

作者： ge Benwei LIU Anna College of Tourism and Environment Shaanxi Normal University Xi＇an Shaanxi 710062 China Department of geography Shihezi University Shihezi Xinjiang 832000 China

Radionuclides, such as 238U, 232Th and 40K, can be found in urban soil. To evaluate the natural radioactivity in the environment, soil samples were collected form Shihezi city and radioisotope concentrations were determined by X-ray fluorescence. The dose rate of urban soil (mGy per year, mGy/a) was calculated. The results indicate that the U, Th and K concentrations of the urban soils were, respectively, 1.2-3.2 mg/kg, 6.4-12.3 mg/kg and 2.05%-2.24%, with the mean values of 2.47 mg/kg, 10.47 mg/kg and 2.16 %. Dose rates of urban soils were 10.04-19.55 mGy/a with the mean value of 16.31 mGy/a. This dose rate is the perfect and maximum value of natural radiation in soil and different with the air absorbed dose rate from terrestrial γ-rays. The mean value of air absorbed dose rate was about 57.42 nGy/h. The annual effective dose rate in air was about 0.07 mSv/a and the average value of Raeq in urban soil was 120.37 Bq/kg. The relative contribution of α particle to the dose rate is higher than that derived from β- and γ-rays in the urban soils.

关键词：城市土壤放射性环境天然放射性石河子市中国放射性同位素剂量率放射性核素

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