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An Adaptive Objective Function for Evaporation Duct Estimations from Radar Sea Echo

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Chinese Physics Letters 2011年第3期28卷 107-110页

作者： ZHANG jin-peng wu Zhen-Sen WAN Bo School of Science Xidian UniversityXi’an 710071

In the process of atmospheric refractivity estimation from radar sea echo,the objective function that calculates the match between the predicted and observed field plays an important *** reduce the effect of noises from long ranges on the objective function,we present a selection method of final ranges for *** adaptive objective function is introduced with a linear distance weight added to the least squares error function(LSEF).Through an evaporation duct height(EDH)retrieving process,the performance of the adaptive objective function is *** result illustrates that the present method performs better than the LSEF in EDH inversions from clutters with different clutter-to-noise ratios.

关键词： function noise process

Phase noise correction for OFDM signal based on DCT approach and variational inference

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The Journal of China Universities of Posts and Telecommunications 2012年第3期19卷 27-32页

作者： CHEN peng LI Nan LI ju-hu HE Zhi-qiang wu Wei-ling Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

A novel scheme to joint phase noise （PHN） correcting and channel noise variance estimating for orthogonal frequency division multiplexing （OFDM） signal was proposed, The new scheme was based on the variational Bayes （VB） method and discrete cosine transform （DCT） approximation. Compared with the least squares （LS） based scheme, the proposed scheme could overcome the over-fitting phenomenon and thus lead to an improved performance. Computer simulations showed that the proposed VB based scheme outperforms the existing LS based scheme

关键词： variational Bayes method discrete cosine transform phase noise OFDM

Improving the electrocatalytic performances of Pt-based catalysts for oxygen reduction reaction via strong interactions with single-CoN_(4)-rich carbon support

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Chinese Chemical Letters 2024年第5期35卷 265-271页

作者： jin Long Xingqun Zheng Bin Wang Chenzhong wu Qingmei Wang Lishan peng Guizhou University Key Laboratory of Green Chemical and Clean Energy Technology Guizhou University Engineering Research Center of Efficient Utilization for Industrial WasteInstitute of Dual-carbon and New Energy Technology Innovation and Development of Guizhou ProvinceSchool of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025China College of Safety Engineering Chongqing University of Science&TechnologyChongqing 401331China Key Laboratory of Rare Earths Chinese Academy of SciencesGanjiang Innovation AcademyGanzhou 341119China

Developing platinum-group-metal(PGM)catalysts possessing strong metal-support interaction and controllable PGM size is urgent for the sluggish oxygen reduction reaction(ORR)in proton-exchange membrane fuel ***,we propose an in-situ self-assembled reduction strategy to successfully induce highly-dispersed sub-3nm platinum nanoparticles(Pt NPs)to attach on resin-derived atomic Co coordinated by N-doped carbon substrate(Pt/Co_(SA)-N-C)for *** be specific,the interfacial electron interaction effect,along with a highly robust Co_(SA)-N-C support endow the as-fabricated Pt/Co_(SA)-N-C catalyst with significantly enhanced catalytic properties,i.e.,a mass activity(MA)of 0.719 A/mgPt at 0.9 ViR-free and a reduction of 24.2%in MA after a 20,000-cycles *** functional theory(DFT)calculations demonstrate that the enhanced electron interaction between Pt and Co_(SA)-N-C support decreases the dband center of Pt,which is in favor of lowering the desorption energy of ^(*)OH on Pt/Co_(SA)-N-C surface and accelerating the formation of H_(2)O,thus enhance the instinct activity of ***,the higher binding energy between Pt and Co_(SA)-N-C compared to Pt and C indicates that the migration of Pt has been suppressed,which theoretically explains the improved durability of Pt/Co_(SA)-*** work offers an enlightenment on constructing composite Pt-based catalysts with multiple active sites.

关键词： Fuel cells Oxygen reduction reaction Platinum Single-CoN_(4)-rich carbon support Metal-substrate interaction

High efficiency of protoplast preparation for artificially cultured Ulva prolifera(Ulvophyceae,Chlorophyta)

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Journal of Oceanology and Limnology 2018年第5期36卷 1806-1811页

作者： wu Chunhui JIANG peng ZHAO jin FU Huihui Key Laboratory of Experimental Marine Biology Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

Protoplast isolation was relevant for gene manipulation in U lva, and universal protocols have been proposed based on evaluation for various wildly collected species. However, only clonal laboratory cultures were practical for genetic transformation, and whether applicability of such universal protocol existed for these artificial cultures has never been investigated. In this research, samples in different physiological states or developmental stages were tested in U. prolifera. The results proved that the protoplast yields were strongly dependent on the characteristics of samples. Neither F_v/F_m value nor chlorophyll content exhibited an ideal correlation with the protoplast yields. Alternatively, specific growth rate, coupled with developmental stage, could serve as an ef fective combined index to determine the right time for protoplast isolation. According to this instruction, here we reported the highest yields of protoplast((31.5±1.9)×10~6 cells/g f. wt.) in U. prolifera, following comparison between protocols, and further optimizations on enzyme content, incubation period, starting biomass and pretreatment. This specified protocol for artificially cultured clonal samples could meet the need for protoplast-mediated genetic transformation in U. prolifera.

关键词： protoplast Ulva prolifera regeneration artificial culture

Multiple factors influencing high-purity indium electrolytic refining

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Chinese Journal of Chemical Engineering 2024年第7期71卷 148-160页

作者： Hong-Qiang Fan Fei Li Hong-Xing Zheng wu-ji Pan Mei-Zhen wu Yashar Behnamian ju-Bo peng Dong-Hai Lin State Key Laboratory of Advanced Special Steel&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Shanghai Engineering Research Center for Integrated Circuits and Advanced Display Materials Shanghai UniversityShanghai 200444China Research&Development Center Yunnan Tin Group(Holding)Limited CompanyKunming 650032China Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 2V4AlbertaCanada School of Energy and Materials Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China

The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were *** variations in impurity levels concerning gelatin concentration were *** the gelatin and In3+concentration were moderately positively correlated with the Pb *** Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl *** Bi element content was positively linked to the electrode *** the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually ***,a critical current density of 45 A·m^(-2) was identified in this behavior.

关键词： High-purity indium Electrolysis Multiple factors Electrochemistry Purification

Generation mechanism of NO_(x)and N_(2)O precursors(NH_(3)and HCN)from aspartic acid pyrolysis:A DFT study

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International Journal of Agricultural and Biological Engineering 2016年第5期9卷 166-176页

作者： Kang peng Qin wu Fu Zongqiang Wang Tipeng ju Liwei Tan Zhongfu Institute of Energy Economics and Environment School of Economics and ManagementNorth China Electric Power UniversityBeijing 102206China National Engineering Laboratory for Biomass Power Generation Equipment School of Renewable Energy EngineeringNorth China Electric Power UniversityBeijing 102206China School of Materials Science and Mechanical Engineering Beijing Technology and Business UniversityBeijing 100048China

In order to better understand the mechanism of NO_(x)and N_(2)Oprecursors(NH_(3)and HCN)from aspartic acid(Asp)pyrolysis,decomposition reaction networks resulting in the generation of NH_(3)and HCN were investigated by employing density function theory *** several pathways were analyzed in detail,two series of pyrolytic reactions containing three possible pathways were *** the reactants,transition states,intermediates and products were optimized,also the electronic properties on these crucial points were discussed,which shows that Cαacts as the most active site to initiate the pyrolysis reaction,where the direct Cα-Cβbond breakage,due to the atomic charge population of repulsion,led to one key route for the generation of HCN,and the transfer of Hαfrom Cαto Cβresulting in another key route for the generation of HCN,while the transfer of Hαfrom Cαto N atom of Asp resulting in the key route for the generation of ***,the kinetic analysis based on speed control method in each key reaction pathway was conducted to further compare the generation of HCN and NH_(3)under various *** above results are in accordance with the related experimental results.

关键词： pyrolysis aspartic acid(Asp) amino acid DFT

Photoproduction of Vector Meson φ off Deuteron in QCD Inspired Model

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Communications in Theoretical Physics 2009年第8期52卷 295-301页

作者： MENG Cheng-ju PAN Ji-Huan peng jin-Song MA Wei-Xing YUAN Tong-Quan Department of Physics and Electronic Engineering Hechi College Yizhou 546300 China Institute of High Energy Physics the Chinese Academy of Sciences Beijing 100049 China

Based on the quark-gluon contents of nucleon and strongly believing that the force mediators,Pomeronand its counterpart in the conventional approach of Regge theory,for high energy diffractive process would be the tensorglueball and Odderon respectively,we discuss photo-production of vector meson φ off the deuteron at energy less than 3GeV in the QCD inspired model in which the quark gluon degrees of freedom and glueball,Odderon exchange are takeninto account.A calculation is performed for γ + D →φ + D,and the theoretical predictions of the differential crosssection dσ^(γD)) /dt,are presented and compared with available experimental *** QCD inspired model reproducesdata quite well in the whole range of the experimental measurements up to |t| ■0.4 *** results can be used toextract γn→φn data,which cannot be measured in experiment.

关键词： photoproduction of vector meson QCD generalized vector meson dominance model QCD

Influence of Chromium on Corrosion Behavior of Low-alloy Steel in Cargo Oil Tank O_2-CO_2-SO_2-H_2S Wet Gas Environment

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Journal of Iron and Steel Research International 2015年第7期22卷 630-637页

作者： peng ZHOU jin-ming LIANG Fei ZHANG Hui-bin wu Di TANG National Engineering Research Center of Advanced Rolling Technology University of Science and Technology Beijing

As international maritime organization （IMO） draft 289 was adopted to develop a low-alloy anti-corrosion steel for the deck of cargo oil tank and to understand corrosion mechanism, corrosion behavior of a low-alloy steel with chromium contents was studied in O2-CO2-SO2-H2 S wet gas environment. Corrosion rate was measured, and the microstructure and morphology of corrosion product film were characterized by scanning electron microscopy （SEM）. The phase and chemical composition of the corrosion product film were investigated by X-ray diffraction （XRD） and energy dispersive spectroscopy （EDS）, respectively. The effect of misorientation distribution on corro- sion resistance of steel was evaluated by electron backscattered diffraction （EBSD）. The results showed that corro- sion rate decreased with increasing chromium content in the low-alloy steel, and the corrosion type was general corrosion. The phenomenon of chromium enrichment was found in corrosion product film consisting of a-FeOOH, γ- FeOOH, sulphur, FeS2 and Fel-xS. The increase of chromium content decreases the amount of high-angle grain boundaries, thus resulting in the improvement of corrosion resistance.

关键词： corrosion cargo oil tank upper deck wet gas low-alloy steel chromium

Diagnosis and treatment of spinal tuberculosis after liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2009年第2期8卷 218-221页

作者： Gu, peng-Cheng wu, Rong-Huan Lin, Xiang-jin Zhejiang Univ Sch Med Affiliated Hosp 1 Dept Orthoped Hangzhou 310003 Zhejiang Peoples R China

BACKGROUND: Spinal tuberculosis is a common disease in orthopedic clinical practice; however, it is seldom reported after organ transplantation. The aim of this study was to investigate the diagnosis and treatment of spinal tuberculosis after organ transplantation. METHOD: Two cases were diagnosed as spinal tuberculosis after liver transplantation and were treated with socarboxazide, rifampicin, streptomycin and ethambutol for more than one year. RESULTS: After treatment with anti-tuberculosis drugs for several months, the symptoms of both patients clearly improved. Back pain disappeared, and erythrocyte sedimentation and body temperature returned to normal. CONCLUSIONS: We should highly suspect spinal tuberculosis if notalgia and night sweats are present after organ transplantation. Anti-tuberculosis therapy is an effective treatment for spinal tuberculosis after organ transplantation.

关键词： tuberculosis, spinal organ transplantation antitubercular agents