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Surface modifications of Pt-based atomically ordered nanoparticles to improve catalytic performances for oxygen reduction reaction

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Progress in Natural Science:Materials International 2020年第6期30卷 890-895页

作者： libo zhang Xiaoran Wang Hong Zhu State Key Laboratory of Chemical Resource Engineering Institute of Modern Catalysis Department of Organic Chemistry Beijing Engineering Centre for Hierarchical Catalysts School of Science Beijing University of Chemical Technology

Bimetallic platinum-cobalt(Pt–Co) nanostructure catalysts represent superior catalytic performances for oxygen reduction reaction(ORR). In a variety of Pt–Co catalyst structures, atomically ordered structure catalysts show excellent catalytic performances in the ORR. In this work, for promoting their catalytic performances, atomically ordered Pt Co nanoparticles(Pt Co/C) with carbon supported were successfully prepared by an improved impregnation method and annealing. Then, the ordered Pt Co/C catalysts have been significantly improved by doped with ultralow amount of Au and Cr transition metal. The physical and electrochemical test results demonstrate the Cr–Pt Co/C and Au–Pt Co/C catalysts have superior catalytic performances including mass activity and stability compared to commercialized Johnson Matthey(JM) Pt/C, which was the result of the modified electronic properties of Pt surface and atomically ordered structure. The presence of Au and Cr enhances the stability of Pt Co/C catalysts. This work represents a simple way to promote the catalytic performances of the atomically ordered catalysts.

关键词： Low-pt Proton exchange membrane fuel cells Atomically ordered structure Oxygen reduction reaction Surface modification

The Taoist Ecological Ethics Concerning Animal Protection

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学术界 2016年第4期 308-313页

作者： zhang libo Huang Qiuyue Institute of Religious Studies Sichuan University

Nowadays,the animal crisis is not only an ethical issue,but also an ecological *** order to resolve this crisis,we should seek ideological support from traditional Chinese *** has the theoretical basis concerning the harmonious relations between human and animals,man and *** the meantime,the religious doctrines also advocate nursing life,loving life and saving life as well as abstention from *** paper attempts to summarize all relevant ideas and carry out a comprehensive research,thus contributing to theories concerning the issue of contemporary animal protection.

关键词： the animal crisis Heaven-Man Oneness religious disciplines the retribution for sin reward and punishment from divinities abstention from voracity and hunting

Structure-based design,synthesis of novel probes for cytochrome P450 OleT

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Chinese Chemical Letters 2021年第4期32卷 1466-1469页

作者： Dumei Ma libo zhang Yingwu Yin Qian Wang Department of Chemical and Biochemical Engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Department of Chemistry and Biochemistry University of South CarolinaColumbiaSC 29208United States

Cytochrome P450 OleT_(SA),a new cytochrome P450 enzyme from Staphylococcus aureus,catalyzes the oxidative decarboxylation and hydroxylation of fatty acids to generate terminal alkenes and fatty *** mechanism of this bifurcative chemistry remains largely ***,a class of derivatized fatty acids were synthesized as probes to investigate the effects of substrate structure on the product type of P450 OleT_(SA).The results demonstrate that the fine-tuned structure of substrates,even in a remote distance from the carboxyl group,significantly regulates OleT catalyzed decarboxylation/hydroxylation *** docking analysis indicated the potential interactions between the carboxylate groups of different probes and the enzyme active center which was attributed to the bifurcative chemistry.

关键词： Substrate engineering Cytochrome P450 OleT Decarboxylation Hydroxylation Fatty acid derivatives

GPU-based discrete element simulation on flow stability of flat-bottomed hopper

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Chinese Journal of Chemical Engineering 2018年第1期26卷 43-52页

作者： Li Peng Zheng Zou libo zhang Qingshan Zhu Hongzhong Li State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChineseAcademy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

In this study, the flow stability of the flat-bottomed hopper was investigated via GPU-based discrete element method(DEM) simulation. With the material height inside the hopper reducing, the fluctuation of the flow rate indicates an unstable discharge. The flow regions of the unstable discharge were compared with that of the stable discharge, a key transformation zone, where the voidage showed the largest difference between unstable and stable discharge, was revealed. To identify the relevance of the key transformation zone and the hopper flow stability, the voidage variation of the key transformation zone with material height reducing was studied.A sharp increase in the voidage in the key transformation zone was considered to be the standard for judging the unstable hopper flow, and the ‘Top–Bottom effect' of the hopper was defined, which indicated the hopper flow was unstable when the hopper only had the top area and the bottom area, because the voidage of particles in the top area and the bottom area were both variables.

关键词： Stability Discrete element method(DEM) Granular flow Top-Bottom effect Flow regions

Visual object tracking:Progress,challenge,and future

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The Innovation 2023年第2期4卷 19-20页

作者： libo zhang Heng Fan Institute of Software Chinese Academy of SciencesBeijing 100190China Department of Computer Science and Engineering University of North TexasDentonTX 76206USA Nanjing Institute of Software Technology Nanjing 210000China

Visual object tracking aims to continuously localize the target object of interest in a video *** one of the most fundamental problems in computer vision,visual object tracking has a long list of critical applications including video surveillance,autonomous driving,human-machine interaction,augmented reality,robotics,etc.,in which the tracking system provides the capacity to report target positions in real time for subsequent visual *** the past decades,visual object tracking has been extensively explored and has witnessed considerable progress,especially in deep-learning-based tracking.

关键词： Visual visual computer

Oxidation of petroleum-based byproducts diformyltricyclodecanes(DFTD)with O2 under catalyst-free and ultra-low temperature

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Chinese Journal of Chemical Engineering 2020年第1期28卷 266-270页

作者： libo zhang Bowen Xing Bailian Deng Tianfu Wang Hui Ming State Key Laboratory of Heavy Oil Processing College of EngineeringChina University of Petroleum-Beijing at KaramayKaramay 834000China The Key Laboratory of Plant Resources and Chemistry of Arid Zone The Xinjiang Technical Institute of Physics&ChemistryChinese Academy of SciencesUrumqi 830011China

Oxidation of petroleum-based byproduct dicyclopentadiene derived diformyltricyclodecanes(DFTD) to dicarboxyltriclodecanesacids(DCTDA) was conducted under catalyst-free and ultra-low temperature conditions with O2 as oxidant. In the perspective of industry process, oxygen pressure and contents, solvent and raw material initial concentrations were screened to evaluate their influence on DCTDA generation. Results indicate that DFTD oxidation can occur rather easily under no-catalyst and ultra-low temperature conditions with O2 as oxidant. Oxygen content and pressure had positive effect on DCTDA production, γ-valerolactone(GVL) behaved best on DFTD generation in dynamics, while methanol could be used as a protective solvent to preserve ***, the existence of water in solvent was not beneficial to DCTDA production because of poor DFTD compatibility with water. The mechanisms of O2 and solvent influence on DCTDA generation were discussed. Meanwhile,the oxidation route of DFTD–Intermediate–DCTDA was proposed. The present work exhibits the valued potential of DFTD, which will have a positive effect on high added value of petroleum based by-products.

关键词： Diformyltricyclodecanes Oxidation Catalyst-free Solvent Oxidative route

Spectroscopic studies of the interaction between phosphorus heterocycles and cytochrome P450

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Journal of Pharmaceutical Analysis 2021年第6期11卷 757-763页

作者： Dumei Ma libo zhang Yingwu Yin Yuxing Gao Qian Wang Department of Chemical and Biochemical Engineering College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005FujianChina Department of Chemistry and Biochemistry University of South CarolinaColumbiaSC29208USA Department of Chemistry and Key Laboratory for Chemical Biology of Fujian Province College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005FujianChina

P450 fatty acid decarboxylase Ole T from Staphylococcus aureus(Ole TSA)is a novel cytochrome P450 enzyme that catalyzes the oxidative decarboxylation of fatty acids to yield primarily terminal alkenes and CO_(2) or minor a-andβ-hydroxylated fatty acids as *** this work,the interactions between a series of cycloalkyl phosphorus heterocycles(CPHs)and Ole TSAwere investigated in detail by fluorescence titration experiment,ultraviolet-visible(UV-vis)and31 P NMR *** titration experiment results clearly showed that a dynamic quenching occurred when CPH-6,a representative CPHs,interacted with Ole TSAwith a binding constant value of 15.2×104 M-1 at 293 *** thermodynamic parameters(ΔH,ΔS andΔG)showed that the hydrogen bond and van der Waals force played major roles in the interaction between Ole TSAand *** UV-vis and31 P NMR studies indicated the penetration of CPH-6 into the interior environment of Ole TSA,which greatly affects the enzymatic activity of Ole ***,our study revealed an effective way to use phosphorus heterocyclic compounds to modulate the activity of cytochrome P450 enzymes.

关键词： Phosphorus heterocycles Cytochrome P450 Ole T Interaction Spectroscopy

Dielectric Properties and Microwave Heating of Molybdenite Concentrate at 2.45 GHz Frequency

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Journal of Beijing Institute of Technology 2018年第1期27卷 83-91页

作者： Yonglin Jiang Bingguo Liu Jinhui Peng libo zhang National Local Joint Engineering Laboratory of Engineering Applications of Microwave Energy and Equipment Technology Kunming 550093 China Key Laboratory of Unconventional Metallurgy Ministry of Education Kunming University of Science and Technology Kunming 550093 China Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Kunming 550093 China

Dielectric properties were measured using cavity perturbation method. The temperature rising behaviors of molybdenite concentrate were investigated in the field of microwave. This process was conducted to show the microwave absorption properties of molybdenite concentrate and the feasibility of microwave roasting molybdenite concentrate to prepare high purity MOO3. The dielectric constant,dielectric loss,and loss tangent increase from 3. 51 to 5. 04,0. 22 to 0. 51 and 0. 065 to 0. 102 respectively. They are proportional to the apparent density of molybdenite concentrate in the range of 0. 9-1. 4 g/cm3. The results show that the molybdenite concentrate has good microwave absorption capacity in the conventional density range. The temperature rising curves show that the apparent heating rate of the molybdenite concentrate increases with the increase in microwave power and decreases with the increase in the sample mass and thickness. The temperature of concentrate sample of 100 g reaches approximately 800 ℃ after 5 min of microwave treatment at 0. 5 kW of power. Our findings show that it is feasible to prepare high-purity MOO3from molybdenite concentrate by microwave roasting.

关键词： dielectric properties temperature molybdenite concentrate microwave M_OO_3

Prediction model of microwave calcining of ammonium diuranate using incremental improved back-propagation neural network

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Acta Metallurgica Sinica(English Letters) 2011年第1期24卷 34-42页

作者： Yingwei LI Bingguo LIU Jinhui PENG Wei LI Daifu HUANG libo zhang Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093 China Key Laboratory of Unconventional Metallurgy Ministry of Education Kunming University of Scienceand Technology Kunming 650093 China No.272 Nuclear Industry Factory China National Nuclear Corporation Hengyang 421002 ChinaMamlscript received 2~~ May 2010 in revised form 17 October 2010

The incremental improved Back-Propagation （BP） neural network prediction model using the Levenberg-Marquardt algorithm based on optimizing theory is put forward, which can solve the problems existing in the process of calcinations for ammonium diuranate （ADU） by microwave heating, such as long testing cycle, high testing quan- tity, difficulty of optimization for process parameters. Many training data probably were offered by the way of increment batch and the limitation of the system mem- ory could make the training data infeasible when the sample scale was large. The prediction model of the nonlinear system is built, which can effectively predict the experiment of microwave calcining of ADU, and the incremental improved BP neural network is very useful in overeoining the local minimum problem, finding the global optimal solution and accelerating the convergence speed.

关键词： Microwave calcinations ADU Increment BP neural network Prediction