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Use of bionic inspired surfaces for aerodynamic drag reduction on motor vehicle body panels

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 543-551页

作者： xiao-wen song guo-geng ZHANG Yun WANG Shu-gen HU Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China

Inspired by the successful applications of biological non-smoothness,we introduced bionic non-smooth surfaces as appendices into vehicle body design,aiming to further reduce aerodynamic *** size range of the non-smooth units with pits and grooves was determined according to our analysis with the mechanisms underlying non-smooth unit mediated aerodynamic drag *** bionic non-smooth units reported here were designed to adapt the structure of a given vehicle body from the point of boundary layer control that reduces the burst and the loss of turbulent kinetic *** engine cover lid and vehicle body cap were individually treated with the non-smooth units,and the treated vehicles were subjected to aerodynamic drag coefficient simulation tests using the computational fluid dynamics(CFD) analysis *** simulation results showed that,in comparison with smooth surfaces,properly designed non-smooth surfaces can have greater effects on drag *** mechanism underlying drag reduction mediated by non-smooth surfaces was revealed by further analyses,in which the effects of non-smooth and smooth surfaces were directly compared.

关键词： Computational fluid dynamics(CFD) Bionics Non-smooth surface Aerodynamic drag reduction Vehicle body

Detection of hepatitis C virus core antigen for early diagnosis of hepatitis C virus infection in plasma donor in China

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World Journal of Gastroenterology 2007年第19期13卷 2738-2742页

作者： He-Qiu Zhang Shao-Bo Li guo-Hua Wang Kun Chen xiao-guo song xiao-Yan Feng Department of Vaccine Engineering Beijing Institute of Basic Medical Sciences Beijing 100850 China Hunan Kingda Gene Ltd. Co. Changsha 410000 Hunan Province China

AIM： To evaluate the efficacy of a new hepatitis C virus （HCV） core antigen assay developed in China. METHODS： After the determination of HCV infection, 49 serial samples were selected from II regular plasma donors in 5 different plasma stations. To compare the performance of HCV core antigen detection and HCV PCR, these samples were genotyped, and each specimen was analyzed by ELISA for the detection of HCV core antigen and by qualitative HCV PCR. RESULTS： Among all of the sequential samples, the original 23 specimens were HCV RNA-negative, and 36 samples were HCV RNA-positive. Twenty-seven samples （75%） were HCV core antigen-positive from these HCV RNA-positive specimens. Conversely, 27 samples （93.2%） were found HCV RNA-positive in HCV core antigen- positive samples. Intervals between HCV RNA and HCV core antigen-positive, as well as between HCV core antigen-positive and HCV antibody-positive were 36.0 and 32.8 d, respectively. CONCLUSION： This HCV core antigen assay, developed in China, is able to detect much of anti-HCV-negative, HCV RNA-positive preseroconversion window period （PWP） plasma donations.

关键词： Hepatitis C virus Core antigen Anti-HCV HCV RNA

Growth of Graphene Nanoribbons and Carbon Onions from Polymer

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Chinese Physics Letters 2011年第7期28卷 246-249页

作者： guo xiao-song LU Bing-An XIE Er-Qing Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Physical Science and Technology SchoolLanzhou UniversityLanzhou 730000

Graphene nanoribbons and carbon onions are directly prepared by electron beam irradiation of polyacrylonitrile and expanded polystyrene nanofibers,*** controlling the irradiation process in a high resolution transmission electron microscope,the number of layers of the graphene nanoribbons,as well as the dimension of the carbon onions,can be *** is found that the initial diameter of the nanofiber has a strong effect on the final results.A mechanism is proposed to explain the transformation of polymer nanofibers to carbon nanostructures under electron beam *** supposes that the polymer nanofibers are first carbonized and then graphitized as a result of the high energy *** to the mechanism,it is believed that all polymer nanofibers could be carbonized and then converted to graphene nanoribbons by proper electron beam irradiation.

关键词： fibers mechanism beam

A Novel Model of the H Radical in Hot-Filament Chemical Vapor Deposition

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Chinese Physics Letters 2011年第2期28卷 216-219页

作者： guo xiao-song BAO Zhong ZHANG Shan-Shan XIE Er-Qing Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Physical Science and Technology SchoolLanzhou UniversityLanzhou 730000

Amorphous hydrogenated and crystalline silicon thin films were prepared by hot-filament chemical vapor deposition.A structural transformation from amorphous phase to crystalline phase by increasing the filament temperature Tfil from 1600℃ to 1650℃ was *** phenomenon may result from the associated abundance of H radicals participating in the growth of the Silms.A probability distribution model of the H radical is proposed to elucidate this *** to this model,the phase transition is due to a distinct difference in the probability distribution of the H radicals,which seems to be dependent upon Tfil.

关键词： deposition transformation crystalline

Interface microstructure and formation mechanism of ultrasonic spot welding for Al-Ti dissimilar metals

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International Journal of Minerals,Metallurgy and Materials 2021年第9期28卷 1506-1514页

作者： Li Zhou Shan Liu Jie Min Zhi-Wei Qin Wen-Xiong He xiao-guo song Hong-Bo Xu Ji-Cai Feng State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Shandong Provincial Key Laboratory of Special Welding Technology Harbin Institute of Technology(Weihai)Weihai 264209China Research Center for Intelligent Chips Zhejiang LabHangzhou 311121China

The present study focuses on interface microstructure and joint ***6061 aluminum alloy(Al)and commercial pure titanium(Ti)joints were welded by ultrasonic spot welding(USW).The welding energy was 1100-3200 *** Al-Ti joint appearance and interface microstructure were observed mainly via optical microscopy and field emission scanning electron *** indicated that a good joint can be achieved only with proper welding energy of 2150 *** significant intermetallic compound(IMC)was found under all *** high energy barriers of Al-Ti and difficulties in diffusion were the main reasons for the absence of IMC according to kinetic *** heat input is crucial for the material plastic flow and bonding area,which plays an important role in the joint formation.

关键词： ultrasonic spot welding Al-Ti dissimilar material interface mechanism microstructure intermetallic compounds

Afforestation with an age-sequence of Mongolian pine plantation promotes soil microbial residue accumulation in the Horqin Sandy Land, China

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Journal of Arid Land 2024年第4期16卷 567-579页

作者： guo Jingwen song Xueshu WANG xiao DU Zhangliu LU Sen State Key Laboratory of Efficient Production of Forest Resources Research Institute of ForestryChinese Academy of ForestryBeijing 100091China Co-Innovation Center for Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing 210037China College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China

Land use change affects the balance of organic carbon(C)reserves and the global C *** residues are essential constituents of stable soil organic C(SOC).However,it remains unclear how microbial residue changes over time following *** this study,16-,23-,52-,and 62-year-old Mongolian pine stands and 16-year-old cropland were studied in the Horqin Sandy Land,*** analyzed changes in SOC,amino sugar content,and microbial parameters to assess how microbial communities influence soil C transformation and *** results showed that SOC storage increased with stand age in the early stage of afforestation but remained unchanged at about 1.27-1.29 kg/m2 after 52 ***,there were consistent increases in amino sugars and microbial residues with increasing stand *** stand age increased from 16 to 62 a,soil pH decreased from 6.84 to 5.71,and the concentration of total amino sugars increased from 178.53 to 509.99 mg/kg.A significant negative correlation between soil pH and the concentration of specific and total amino sugars was observed,indicating that the effects of soil acidification promote amino sugar stabilization during *** contrast to the Mongolian pine plantation of the same age,the cropland accumulated more SOC and microbial residues because of fertilizer *** Mongolian pine plantation with different ages,there was no significant change in calculated contribution of bacterial or fungal residues to SOC,suggesting that fungi were consistently the dominant contributors to SOC with increasing *** results indicate that afforestation in the Horqin Sandy Land promotes efficient microbial growth and residue accumulation in SOC stocks and has a consistent positive impact on SOC persistence.

关键词： soil organic matter stand age biomarker amino sugars microbial residues

Characteristics and stability of oxide+carbonitride in H13 steel at 1250℃

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Journal of Iron and Steel Research International 2024年第1期31卷 134-142页

作者： xiao-lin Sun Han-jie guo Jing guo Fei Wang Dong Xu Gao-yang song Shuai Wang School of Materials Science and Engineering Hebei University of EngineeringHandan056038HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China High Temperature Materials Research Institute Central Iron and Steel Research Institute Co.Ltd.Beijing100081China Technology Innovation Center for High Quality Cold Heading Steel of Hebei Province Hebei University of EngineeringHandan056038HebeiChina

The morphology,size,quantity,and composition of complex oxide+carbonitride in H13 steel held at 1250℃for 5,10,and 15 h were *** results show that the ratio and number of complex carbonitrides with cores in H13 steel are gradually increased when holding at 1250℃compared with those in the original H13 steel,and the core size *** are one or more oxide cores in(Ti_(x),V_(1-x))(Cy,N_(1-y)),including xCaO·zAl_(2)O_(3),xCaO·yMgO·zAl_(2)O_(3),and CaO after holding at 1250℃,in addition to MgO·Al_(2)O_(3)and Al_(2)O_(3)in the original *** equilibrium temperature for(Ti_(x),V_(1-x))(Cy,N_(1-y))precipitation at the solidification front and decomposition in the solid state was theoretically analyzed,which was affected by the x value and the product of Ti and N contents in H13 ***,the composition of(Ti_(x),V_(1-x))(Cy,N_(1-y))is influenced by the oxide *** is convinced that(Ti_(x),V_(1-x))(Cy,N_(1-y))with oxide cores has a higher stability,especially for oxides with a high Al_(2)O_(3)*** treatment at high temperature facilitates a more reasonable analysis of oxide+carbonitride,and the generation mechanism of oxide+carbonitride was discussed.

关键词： Complex carbonitride Decomposition Oxide core Characteristic Stability

Evaluation of cross-reactive antibody response to HVR1 in chronic hepatitis C

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World Journal of Gastroenterology 2010年第35期16卷 4460-4466页

作者： Bing-Shui Xiu xiao-Yan Feng Jing He guo-Hua Wang He-Qiu Zhang xiao-guo song Kun Chen Shi-Gan Ling Cui-Xia Zhu Xiang-Ying Zhang Lai Wei Hui-Ying Rao Institute of Basic Medical Sciences Academy of Military Medical Sciences Beijing 100850 China National Institute for Control of Pharma-ceutical and Biological Products Beijing 100050 China Hepatology Institute People Hospital Peking University Beijing 100044China

AIM:To evaluate the presence and cross-reactive anti-bodies against hypervariable region 1(HVR1) in hepatitis C virus(HCV) infected patients and its relationship with the progression of the ***:Sixteen representative HVR1 proteins selected from a unique set of 1600 natural sequences were used to semiquantitate the cross-reactivity of HVR1 antibodies in the sera of HCV ***-five chronic HCV patients including 23 with asymptomatic mild hepatitis,18 with chronic hepatitis and 16 with liver cirrhosis patients were ***:The degree of the cross-reactivity of anti-HVR1 antibodies in 23 patients with mild asymptomatic hepatitis was 3.09 ± 2.68,which was signif icantly lower than in those with chronic hepatitis(5.44 ± 3.93,P < 0.05) and liver cirrhosis(7.44 ± 3.90,P < 0.01).No correlation was observed between the broadness of the cross-reactivity anti-HVR1 antibodies and patient's age,infection time,serum alanine aminotransferase activity,or serum HCV-RNA *** was the breath of cross-reactivity rather than the presence of anti-HVR1 antibody in HCV sera that was associated with the progression of liver ***:The broadly cross-reactive HVR1 antibodies generated in natural HCV patients can not neutralize the virus,which results in persistent infection in patients with chronic hepatitis.

关键词： Hepatitis C virus Hypervariable region 1 Cross-reactivity

A widely used nonionic surfactant with desired functional groups as aqueous electrolyte additives for stabilizing Zn anode

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Rare Metals 2024年第8期43卷 3692-3701页

作者： Yue-Xian song xiao-Feng Wang Cai-Bin Liu Kai-Xuan guo Xu-Huan guo xiao-Bin Zhong Yao-Hui Zhang Kai Wang Hui-Juan guo Li-Xin Zhang Jun-Fei Liang School of Energy and Power Engineering North University of ChinaTaiyuan 030051China Key Laboratory of Green Chemical Process of Ministry of Education Hubei Key Laboratory of Novel Chemical Reactor and Green Chemical TechnologySchool of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhan 430073China Shanxi Provincial Key Laboratory for High Performance Battery Materials and Devices Taiyuan 030051China

Aqueous Zn-ion batteries(AZIBs) have emerged as potential candidates for Li-ion batteries due to their intrinsic safety and high ***,metallic Zn anodes encounter dendrite growth and water-induced corrosion,rendering poor stability and severe irreversibility at the electrode/electrolyte interface during *** stabilize the Zn anode,we report a low-cost and effective nonionic surfactant,Tween-20 polymer,as an electrolyte additive for *** Tween-20,sequential oxyethylene groups tended to be preferentially adsorbed on the Zn electrode to form a shielding layer for regulating uniform Zn ***,the hydrophobic hendecyl chains prevented H_(2)O-induced corrosion on the Zn anode *** from the desired functional groups,when only trace amounts of Tween-20(0.050 g·L^(-1)) were used,the Zn anode displayed good cycling stability over 2170 h at10 mA·cm^(-2) and a high average Coulombic efficiency of98.94% over 1000 *** Tween-20 polymer can also be effectively employed in MnO_(2)/Zn full *** their toxicity,price and amount of usage,these surfactant additives provide a promising strategy for realizing the stability and reversibility of high-performance Zn anodes.

关键词： Zn anode Dendrite growth Tween-20 polymer Surfactant additive Aqueous electrolyte