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Chemical Research in Chinese Universities 2000年第3期16卷 213-217页

作者： WANG Yi-xuan bu yu-xiang LIU Cheng-bu Faculty of Chemistry Shandong UniversityJinan 250100P.R.China

We proposed a simple potential harmonic(PH) scheme for calculating the non\|relativistic radial correlation energies of atomic systems. The scheme was applied to the low\|lying \%n\%\+1\%S\%(\%n\%=1,2) and \%n\%\+3\%S\%(\%n\%=2,3) states of the helium atom. The results exhibit a very stable convergence characterization in both the angular and radial directions with PH and generalized Laguerre functions(GLF) respectively, even though the method is non\|variational one. The ninth significant figure of the non\|relativistic radial energy(NRE) calculated for the ground state exactly agrees with that of the most accurate literature data from the modified configuration interaction method. The convergent NRE′s for the excited states 2\+1\%S\%, 2\+3\%S\% and 3\+3\%S\% with the similar accuracy were also obtained.

关键词： Potential harmonic Radial limit Schrdinger equation Helium atom

Enhancement and Removal of PM_(2.5)by Cold and Warm Air Masses Accompanying Certain Synoptic Weather Systems across Hangzhou,China during 2014-2020

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Journal of Meteorological Research 2024年第3期38卷 620-634页

作者： bu yu Feng CHEN Hanqing KANG Bin ZHU Hongnian LIU Hangzhou Meteorological bureau Hangzhou310051China Hangzhou International Urbanology Research Center for Urban Governance Studies Hangzhou311121China Zhejiang Institute of Meteorological Sciences Hangzhou310008China Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science&TechnologyNanjing210044China School of Atmospheric Sciences Nanjing UniversityNanjing210023China

Local air pollution is strongly affected by synoptic weather systems,such as fronts,troughs,low-altitude vortices,or high-altitude ***,few studies have analyzed the meteorological properties of cold or warm air masses associated to these systems and their impact on local air *** this study,hourly observations of fine particulate matter(diameter of up to 2.5µm,i.e.,PM_(2.5)),wind(V),temperature(T),pressure(P),and precipitation(R),acquired in Hangzhou in 2014-2020,were *** this analysis,weather patterns were categorized into 27 types;89 and 94 cases illustrating the passage of warm and cold air masses over Hangzhou were identified,respectively;the influence of air mass temperature,wind speed,and wind direction on PM_(2.5) concentrations and local accumulation or removal was *** main results are as follows.(1)Pollution events occurred more frequently for cold than for warm air masses,but average pollutant concentration was lower for cold air masses;(2)48%of the cold air mass cases corresponded to PM_(2.5) decreases and 52%to PM_(2.5) increases,with strong cold air masses(ΔT_(24h)>4°C;∣V∣_(average)>4 m s^(−1))markedly reducing local pollution,but weak cold air masses(ΔT24h4°C)reduced the PM_(2.5) concentration whereas weaker winds(∣V∣_(average)but more gradually within 14 h after the passage of strong warm air *** results considerably improve the current understanding of the influence of cold and warm air masses on local pollution patterns.

关键词： weather type air mass enhancement removal meteorological condition

Self-assembling nacre-like high-strength and extremely tough polymer composites with new toughening mechanism

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Journal of Materials Science & Technology 2023年第5期136卷 236-244页

作者： yu bu Xu Wang Xiuming bu Zhengyi Mao Zhou Chen Zebiao Li Fengqian Hao Johnny C.Ho Jian Lu Cityu-Shenzhen Futian Research Institute Shenzhen 518045China Centre for Advanced Structural Materials City University of Hong Kong Shenzhen Research InstituteGreater Bay Joint DivisionShenyang National Laboratory for Materials Science8 Yuexing 1st RoadShenzhen Hi-Tech Industrial ParkNanshan DistrictShenzhen 518000China MOE Key Laboratory of Impact and Safety Engineering Ningbo UniversityNingbo 315211China Department of Materials Science and Engineering City University of Hong KongHong Kong SAR 999077China Department of Mechanical Engineering City University of Hong KongHong Kong SAR 999077China

Achieving high strength,deformability and toughness in polymers is important for practical industrial *** has remained challenging because of the mutually opposing effects of improvements to each of these ***,a self-assembling nacre-like polymer composite is designed to achieve ex-tremely tough with increasing *** special design significantly improved polymer’s mechanical properties,including an ultra-high fracture strain of 1180%,a tensile strength of 55.4 MPa and a toughness of 506.9 MJ/m^(3),which far exceed the highest values previously reported for polymer *** ex-cellent combination of properties can be attributed to a novel toughening mechanism,achieved by the synergy of the domain-limiting effect of metallic glass fragments with the strain-gradient-induced orien-tation and crystallisation within the polymer during *** approach opens a promising avenue for designing robust polymer materials in armour and aerospace engineering for a range of innovative applications.

关键词： Polymer composites Metallic glass thin film Toughness Toughening mechanism Nacre-like fracture

Study on the Nonlinear Tension-Torsion Coupled Stiffness of the High-Current Composite Umbilical Considering the Thermal Effect

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China Ocean Engineering 2022年第4期36卷 588-600页

作者： YAN Jun SU Qi bu yu-feng LU Qing-zhen YANG Zhi-xun State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsDalian University of TechnologyDalian 116024China Ningbo Institube of Dalian University of Technology Ningbo 315040China State Key Laboratory of Structural Analysis for Industrial Equipment School of Ocean Science and TechnologyDalian University of TechnologyPanjin 124221China Institute of marine machinery College of Mechanical and ElectricalEngineering Harbin Engineering UniversityHarbin 150001China

The gradual advances of offshore oil and gas exploitation and the development tendency of equipment integration have prompted the design of a new type of the high-current composite umbilical to meet development *** order to study the mechanical behavior of the high-current composite umbilical(HCCU)and provide design suggestions,a theoretical analysis framework of the tension-torsion coupled behavior of the spirally wound structure is proposed,which focuses more on the radial mechanical ***,by considering the mechanical and thermal conditions during the operation of HCCU,a semi-analytical method of the tension and torsion stiffness of the high-current composite umbilical considering the temperature effect is ***,a practical case of HCCU is given,and the thermal effect on the radial and axial mechanical behaviors are *** is found that the thermal effect has a significant influence on the radial stiffness,and shows non-linear variation ***,the sensitivity analysis is carried out to study the influence of the design parameter on the stiffness of tension and *** results indicated that the equivalent radial stiffness and helical angle have obvious effect on the tension-torsion coupled stiffness,which can provide reasonable reference for the design of HCCU.

关键词： high-current composite umbilical tension-torsion coupled thermo-mechanical coupled radial stiffness

Entanglement for a Bimodal Cavity Field Interacting with a Two-Level Atom

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Communications in Theoretical Physics 2009年第7期52卷 133-136页

作者： LIU Jia CHEN Zi-yu bu Shen-Ping ZHANG Guo-Feng Department of Physics Beijing University of Aeronautics and Astronautics Beijing 100083 China

Negativity has been adopted to investigate the entanglement in a system composed of a two-level atom anda two-mode cavity *** of Kerr-like medium and the number of photon inside the cavity on the entanglementare *** results show that atomic initial state must be superposed,so that the two cavity field modes can ***,we also conclude that the number of photon in the two cavity mode should be *** interactionbetween modes,namely,the Kerr effect,has a significant negative *** that the atom frequency and thecavity frequency have an indistinguishable effect,so a corresponding approximation has been made in this *** may be useful for quantum information in optics systems.

关键词： negativity Kerr-like medium Jaynes-Cummings model

Construction, expression and characterization of human interferon α2b-(G4S)n-thymosin α1 fusion proteins in Pichia pastoris

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World Journal of Gastroenterology 2005年第17期11卷 2597-2602页

作者： You-FengYang Han-Yingyuan Nan-SongLiu Xiang-LingChen bu-yuGao HongLu yu-YangLi StateKeyLaboratoryofGeneticEngineering InstituteofGeneticsSchoolofLifeSciencesFudanUniversityShanghai200433China

AIM:Interferon α2b (IFNα2b) and thymosin α1 (Tα1) exhibit synergic effects in the treatment of hepatitis B and hepatitis C when used together. For developing a fusion protein drug, fusion proteins of IFNα2b and Ta1 linked by different lengths of (G4S)n(n = 1-3) were constructed and expressed in Pichia pastoris. METHODS: Using PCR and molecular clone techniques, the fusion genes of IFNα2b-(G4S)n-Tα1 (n = 1-3) were constructed and subcloned into the eukaryotic expression vector pPIC9. After transformation of these plasmids into P. pastoris, the expressed fusion proteins IFNα2b-(G4S) n-Tα1 (n = 1-3) were obtained. These proteins were purified through diethylaminoethyl (DEAE) affinity chromatography and Superdex?75 gel filtration and analyzed by SDS-PAGE and Western blot. Antiviral and E-rosette assays were used to investigate the bioactivities of these fusion proteins. RESULTS: DNA sequencing confirmed that the fusion genes of IFNa2b-(G4S)n-Tα1 (n= 1-3) were correctly cloned to the pPIC9 vector. The recombinant IFNα2b-(G4S)n-Tα1 (n = 1-3) fusion proteins expressed in P. pastoris were purified with DEAE and Superdex?75 gel filtration chromatography. The fusion proteins could be observed on sodium dodecylsulfate-polyacrylamide gel electrophoresis with molecular weight (MW) of 23.2, 22.9, and 22.6 ku, respectively, and reacted to the IFNa2b monoclonal antibody and Tal polyclonal antibody. The purified fusion proteins exhibit antiviral activity and can enhance the percentage of E-rosette-forming-cell in E-rosette assay. CONCLUSION: The recombinant IFNa2b-(G4S)n-Tα1 (n = 1-3) fusion proteins were successfully expressed in P. pastoris. Purified fusion proteins exhibit both antiviral activity of IFNa2b and immunomodulatory activity of Tal in vitro. These results will be the basis for further evaluation of the fusion proteins' function in vivo.

关键词： Fusion protein Interferon α2b Thymosin al Antiviral assay E-rosette assay

Electroacupuncture Attenuates Immune-Inflammatory Response in Hippocampus of Rats with Vascular Dementia by Inhibiting TLR4/MyD88 Signaling Pathway

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Chinese Journal of Integrative Medicine 2022年第2期28卷 153-161页

作者： bu yu LI Wen-shuang LIN Ji WEI yu-wei SUN Qiu-ying ZHU Shi-jie TANG Zhong-sheng School of Basic Medicine Guizhou University of Traditional Chinese MedicineGuiyang(550025)China Department of Hematology the Second Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang(550025)China

Objective:To investigate whether electroacupuncture(EA)alleviates cognitive impairment by suppressing the toll-like receptor 4(TLR4)/myeloid differentiation factor 88(MyD88)signaling pathway,which triggers immune-inflammatory responses in the hippocampus of rats with vascular dementia(VaD).Methods:The experiments were conducted in 3 parts and in total the Sprague-Dawley rats were randomly divided into 8 groups by a random number table,including sham,four-vessel occlusion(4-VO),4-VO+EA,4-VO+non-EA,sham+EA,4-VO+lipopolysaccharide(LPS),4-VO+LPS+EA,and 4-VO+TAK-242 *** VaD model was established by the 4-VO *** days later,rats were treated with EA at 5 acupoints of Baihui(DV 20),Danzhong(RN 17),Geshu(BL 17),Qihai(RN 6)and Sanyinjiao(SP 6),once per day for 3 consecutive *** subsets,lymphocyte transformation rates,and inflammatory cytokines interleukin-6(IL-6)and tumor necrosis factorα(TNF-α)were measured to assess immune function and inflammation in VaD *** electron microscopy was used to observe the ultrastructure of nerve cells in the *** levels of TLR4,MyD88,IL-6,and TNF-αwere detected after EA ***4/MyD88 signaling and cognitive function were also assessed after intracerebroventricular injection of TLR4 antagonist TAK-242 or TLR4 agonist LPS with or without ***:Compared with the 4-VO group,EA notably improved immune function of rats in the 4-VO+EA group,inhibited the protein and mRNA expressions of TLR4 and MyD88 in the hippocampus of rats,reduced the expressions of serum IL-6 and TNF-α(all P0.05).Conclusions:EA attenuated cognitive impairment associated with immune inflammation by inhibition of the TLR4/MyD88 signaling ***,EA may be a promising alternative therapy for the treatment of VaD.

关键词： electroacupuncture vascular dementia immune-inflammation toll-like receptor 4/myeloid differentiation factor 88 signaling pathway

Experimental Study on the Influence of Cross-Section Type of Marine Cable Conductors on the Bending Performance

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China Ocean Engineering 2022年第4期36卷 629-637页

作者： YAN Jun HU Hai-tao LU Hai-long YIN yuan-chao bu yu-feng LU Qing-zhen State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInter-national Research Center for Computational MechanicsDalian University of TechnologyDalian 116024China Ningbo Research Institute of Dalian University of Technology Ningbo 315016China State Key Laboratory of Structural Analysis for Industrial Equipment School of Ocean Science and TechnologyDalian University of TechnologyPanjin 124221China

Through the development of marine energy,marine cables are the key equipment for transmission of electrical energy between surface platforms and underwater *** failure is a critical failure mode of marine *** bending performance of the cable conductor has a major influence on both bending and fatigue performances of the overall cable *** study the influence of different types of the conductor cross-section on the bending performances of marine cable conductors,three types of copper conductors with the same cross-sectional area,i.e.,noncompressed round,compressed round,and shaped wire conductors,were *** experimental results demonstrated that the cross-section type significantly affects the bending performances of copper *** particular,the bending stiffness of the shaped wire conductor is the highest among the three conductor *** key evaluation parameters,i.e.,the bending stiffness,maximum bending moment,envelope area,and engineering critical slip point,were selected to compare and analyze the bending hysteresis curves of the three copper *** differences in the key evaluation parameters were analyzed based on the structural dimensional parameters,processing methods,and classical bending stiffness theoretical models of the three copper conductor *** results provide an important theoretical guidance for the structural design and engineering applications of marine cable conductors.

关键词： marine cable conductors cross-section type bending performance theoretical model bending test

Preparation of Mo_2C nanoparticles dispersion-strengthened copper-based composite by EB-PVD

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Rare Metals 2014年第5期33卷 568-572页

作者： Xiao Li Guang-Ping Song Fan-yu bu Bin Xu Bai-Yang Lou Zhan Lin College of Materials Science and Engineering Zhejiang University of Technology Center for Composite Materials and Structures Harbin Institute of Technology

In this research, a nano-Mo2 C particle dispersion-strengthened copper alloy was prepared by a novel method, i.e., electron beam physical vapor deposition（EBPVD） which has advantages of simple technical process and low cost compared with the conventional mechanical alloying method. And the microstructure and properties of the material were investigated. The results show that the copper matrix is composed of columnar crystals with the average width of 7 lm, and the size of Mo2 C dispersoid is1–7 nm. The ultimate tensile strength of the material is486 MPa, and the electrical conductivity is 82 % IACS. As the temperature increases from 293 to 573 K, the material becomes more brittle.

关键词： Electron beam physical vapor deposition Dispersion-strengthened copper ODS In-situ

Prediction of Load-Displacement Curve of Flexible Pipe Carcass Under Radial Compression Based on Residual Neural Network

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China Ocean Engineering 2023年第1期37卷 42-52页

作者： YAN Jun LI Wen-bo Murilo Augusto VAZ LU Hai-long ZHANG Heng-rui DU Hong-ze bu yu-feng State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsDalian University of TechnologyDalian 116024China Ningbo Research Institute of Dalian University of Technology Ningbo 315016China Ocean Engineering Program Federal University of Rio de JaneiroRio de Janeiro 21941-901Brazil

The carcass layer of flexible pipe comprises a large-angle spiral structure with a complex interlocked stainless steel cross-section profile, which is mainly used to resist radial load. With the complex structure of the carcass layer, an equivalent simplified model is used to study the mechanical properties of the carcass layer. However, the current equivalent carcass model only considers the elastic deformation, and this simplification leads to huge errors in the calculation results. In this study, radial compression experiments were carried out to make the carcasses to undergo plastic deformation. Subsequently, a residual neural network based on the experimental data was established to predict the load-displacement curves of carcasses with different inner diameter in plastic states under radial *** established neural network model’s high precision was verified by experimental data, and the influence of the number of input variables on the accuracy of the neural network was discussed. The conclusion shows that the residual neural network model established based on the experimental data of the small-diameter carcass layer can predict the load-displacement curve of the large-diameter carcass layer in the plastic stage. With the decrease of input data, the prediction accuracy of residual network model in plasticity stage will decrease.

关键词： flexible pipe carcass radial compression experiment load−displacement curves residual neural network