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Petroleum Science 2022年第4期19卷 1905-1914页

作者： yong-rui pi Mu-Tai Bao School of Ocean Yantai UniversityYantai264005China Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education/Institute for Advanced Ocean StudyOcean University of China Qingdao266100China

The enzymes and the characteristics of the community of the petroleum-degrading bacteria play a crucial role in the crude oil biodegradation. The prediction of kinetics of the key groups of hydrocarbons in crude oil was important to evaluate the bioremediation speed and constant. Most of the n-alkanes(C9-C29) were degraded in 25 days, and the average degradation rates of C_(18)~C_(27) higher than 100 μg g^(-1) d^(-1).The hopanes, such as H_(30), had a biodegradation rate more than 10 μg g^(-1) d^(-1). The related enzymes activities changed along with the crude oil biodegradation, especially dehydrogenase. The 16 S rRNA gene amplicon sequencing revealed that Proteobacteria, Firmcutes, Bacteroidetes, Actinobacteria, Acidobacteria were the main petroleum hydrocarbon degraders during the crude oil biodegradation, and the top two highest relative abundance of the genera were Alcaligenes and Acinetobacter. Acinetobacter presented positive correlation to biodegradation of n-alkanes and PAHs. Based on COG analysis, the largest group involved in the general function was amino acid transport and metabolism. The functional categories of bacterial communities were mainly focused on the carbohydrate and amino acid metabolism, xenobiotics biodegradation and metabolism, membrane transport, and so on. Overall, these findings highlight the potential guideline for more adequate monitoring of microbial degradation of crude oil.

关键词： Crude oil Bioaugmentation Kinetics Enzyme activities Microbial functions

Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

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Nano-Micro Letters 2025年第1期17卷 281-292页

作者： Xing Wang Wei pi Sheng Hu Haifeng Bao Na Yao Wei Luo State Key Laboratory of New Textile Materials and Advanced Processing Technology Key Laboratory of New Textile Materials and Applications of Hubei ProvinceSchool of Materials Science and EngineeringWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072People’s Republic of China

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based *** introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in ***,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this *** and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER *** critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

关键词： NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer

High resolution wide swath revisit synthetic aperture radar imaging mode and algorithm

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Journal of Systems Engineering and Electronics 2015年第2期26卷 274-281页

作者： Weihua Zuo Yiming pi rui Min School of Electronic Engineering University of Electronic Science and Technology of China Department of Physics and Information Engineering Huaihua University

Based on the squint mode, a high resolution wide swath revisit synthetic aperture radar （SAR） imaging mode is pro- posed. The transmitting antennas are configured as the single phase center multiple azimuth beams （SPC MAB）. The formed two beams point to two different directions to obtain two images of the observed scenario. The receiving antennas are configured as displaced phase center multiple azimuth beams （DPC MAB） to decrease the required pulse repetition frequency （PRF）. The de- creased PRF can ensure the high resolution wide swath imaging. Based on the analysis of the character of the return signal, a pro- cessing method named multiple beam multiple channel algorithm （MBMCA） is proposed to separate the aliased sub-beams＇ echoes. The separated echoes are focused respectively to get the revisit imaging to the observed scenario. The simulation experiments ve- rify the validity and correctness of the proposed imaging mode and processing algorithm.

关键词： synthetic aperture radar(SAR) high resolution wide swath revisit

EXISTENCE RESULTS FOR THE KIRCHHOFF TYPE EQUATION WITH A GENERAL NONLINEAR TERM

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Acta Mathematica Scientia 2022年第5期42卷 2063-2077页

作者： Huirong pi yong ZENG School of Mathematics and Information Guangci UniversityNanning 530004China

This paper is mainly concerned with existence and nonexistence results for solutions to the Kirchhoff type equation−(a+b∫_(R^(3))|∇u|^(2))Δu+V(x)u=f(u)in R^(3),with the general hypotheses on the nonlinearity f being as introduced by Berestycki and *** analysis introduces variational techniques to the analysis of the effect of the nonlinearity,especially for those cases when the concentration-compactness principle cannot be applied in terms of obtaining the compactness of the bounded Palais-Smale sequences and a minimizing problem related to the existence of a ground state on the Pohozaev manifold rather than the Nehari manifold associated with the equation.

关键词： Kirchhoff type equation general nonlinearity variational methods Pohozaev identity

A New Ensemble HDG Method for Parameterized Convection Diffusion PDEs

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Numerical Mathematics(Theory,Methods and Applications) 2021年第1期14卷 144-175页

作者： yong Yu Gang Chen Liangya pi Yangwen Zhang School of Mathematics Sichuan UniversityChengduChina Department of Mathematics and Statistical Missouri University of Science and TechnologyRollaMOUSA Department of Mathematics Science University of DelawareNewarkDEUSA

A new second order time stepping ensemble hybridizable discontinuous Galerkin method for parameterized convection diffusion PDEs with various initial and boundary conditions,body forces,and time depending coefficients is *** ensemble solutions in L_(∞)(0,T;L^(2)(Ω)),a superconvergent rate with respect to the freedom degree of the globally coupled unknowns for all the polynomials of degree k≥0 is *** results of numerical experiments are consistent with the theoretical findings.

关键词： HDG method ensemble methods parameterized convection diffusion PDEs nu-merical analysis

Synthesis and Crystal Structure of N,N′-4-aminomethyl-pyromellitic diimide

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1176-1180页

作者： LU Xing-Qiang pi Xiang-Dong SU Cheng-yong School of Chemistry and Chemical Engineering Sun Yat-Sen University Guangzhou 510275 China Chemtcal Envtronmental Protectton Monitoring Station of Hubei Wuhan 430060 China

The title compound N,N′-4-aminomethyl-pyromellitic diimide （4-pmpmd） crystallizes in monoclinic, space group P21/c with a = 4.785（1）, b = 6.200（1）, c = 29.907（2） A, β = 93.583（11）°, V= 885.5（2） A^3, Dc = 1.494 g/cm^3, Z= 2, C22H14N4O4, Mr = 398.37,/t（MoKα） = 0.106 mm^-1 and F（000） = 412, and its structure was refined to R = 0.0469 and wR = 0.1017 for 1194 observed reflections （F0 〉 4σ（F0））. The X-ray diffraction shows the existence of the staggered strong intermolecular C-H…O （DA） hydrogen bonds between adjacent molecules, the intermo- lecular C-H…π hydrogen bonds and the weak π…π stacking interactions, leading to the formation of multi-dimensional supramolecular network based on the Z-mode conformation of the title compound.

关键词： N,N′-4-aminomethyl-pyromellitic diimide intermolecular weak interactions,supramolecular network

Formation, Structures and Electronic Properties of Silicene Oxides on Ag(111)

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Journal of Materials Science & Technology 2017年第7期33卷 751-757页

作者： Muhammad Ali Zhenyi Ni Stefaan Cottenier yong Liu Xiaodong pi Deren Yang Centerfor Molecular Modeling （CMM） and Department of Materials Science and Engineering （DMSE） Ghent University Zwijnaarde BE-9052. Belgium

The formation, structural and electronic properties of silicene oxides（SOs） that result from the oxidation of silicene on Ag（111） surface have been investigated in the framework of density functional theory（DFT）.It is found that the honeycomb lattice of silicene on the Ag（111） surface changes after the oxidation. SOs are strongly hybridized with the Ag（111） surface so that they possess metallic band structures. Charge accumulation between SOs and the Ag（111） surface indicates strong chemical bonding, which dramatically affects the electronic properties of SOs. When SOs are peeled off the Ag（111） surface, however, they may become semiconductors.

关键词： Silicene oxides Ag(111) Density functional theory Oxidation Hybridization Band gap

Formation,Stability,Geometry and Band Structure of Organically Surface-Modified Germanane

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Journal of Materials Science & Technology 2017年第1期33卷 59-64页

作者： Hui Jia Rong Wang Zhenyi Ni yong Liu Xiaodong pi Deren Yang State Key Laboratory of Silicon Materials and Department of Materials Science and Engineering Zhejiang University Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of Technology

Surface modification may be an effective means for controlling the properties of germanane, i.e., hydrogenated germanene. In this work, we investigate the formation, stability, structure and electronic properties of surface-modified germanane that results from the hydrogermylation, alkoxylation, aminization or phenylation of germanane. By assuming the typical organic surface coverage of -33%, we have com- pared organically surface-modified germanane with germanene and germanane in the framework of density functional theory. It is found that organically surface-modified germanane may all stably exist despite the endothermic nature of organic surface modification. Organic surface modification leads to the de- crease of the Ge--Ge bond length and the Ge--Ge-Ge bond angle ofgermanane, while causing the buckling distance of germanane to increase. Hydrogenation makes germanene change from a semimetal to a direct- bandgap semiconductor. Organic surface modification further impacts the band structure of the resulting germanane. Hydrogermylated/alkoxylated germanane is a direct-bandgap semiconductor, while aminated/ phenylated germanane is an indirect-bandgap semiconductor. All the organic surface modification gives rise to the increase of the bandgap of germanane.

关键词： Germanane Surface modification Density functional theory Band structure

Fabrication of micro pin fins on inclined V-shaped microchannel walls via laser micromilling

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Advances in Manufacturing 2022年第2期10卷 220-234页

作者： Da-Xiang Deng Jian Zheng Xiao-Long Chen Guang pi yong-Heng Liu School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhenShenzhen 518055GuangdongPeople's Republic of China Department of Mechanical and Electrical Engineering Xiamen UniversityXiamen 361005FujianPeople's Republic of China

A laser-micromilling process was developed for fabricating micro pin fins on inclined V-shaped microchannel walls for enhanced microchannel heat sinks.A pulsed nanosecond fiber laser was *** feasibility and mechanism of the formation of micro pin fins on inclined microchannel walls were investigated for a wide range of processing *** effects of the laser output power,scanning speed,and line spacing on the surface morphologies and geometric sizes of the micro-pin fins were comprehensively examined,together with the material removal *** pin fins with acute cone tips were readily formed on the V-shaped microchannel walls via the piling of recast layers and the downflow of re-solidified materials in the laser-ablation *** pin-fin height exhibited an increasing trend when the scanning speed increased from 100mm/s to 300 mm/s,and it decreased continuously when the line spacing increased from 5μm to 20μ*** optimal processing parameters for preparing micro pin fins on V-shaped microchannels were found to be a laser output power of 21 W,scanning speed of 100-300 mm/s,and line spacing of 2-5μ***,the V-shaped microchannels with micro pin fins induced a 7%-538%boiling heat-transfer enhancement over their counterpart without micro pin fins.

关键词： Laser micromilling Micro pin fins:Microchannels Inclined walls Laser ablation

Starch/Polycaprolactone Blends Compatibilized with Starch Modified Polyurethane

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Chemical Research in Chinese Universities 2010年第3期26卷 483-487页

作者： TAN Ying WANG pi-xin XU Kun AN Hui-yong DONG Li-song Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China Graduate School of Chinese Academy of Sciences Bejing 100049 P. R. China

Starch modified polyurethane（St-PCL） was synthesized via chemical modification of corn starch with hexamethylene diisocyanate terminated polyeaprolactone. The obtained St-PCL with different grafting rates was used as compatibilizer of starch/polycaprolactone（St/PCL） blend. The structure of St-PCL was confirmed by FTIR, and the grafting rate could reach as high as 64%. In addition, a lower St-PCL amount can effectively improve the compatibility of St/PCL blends. And the thermal, mechanical and hydrophobic properties of St/PCL blends could be tailored by the amount of St-PCL.

关键词： Starch Polyurethane Compatibilizer Mechanical property Hydrophobic