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Neural Regeneration Research 2025年第7期20卷 2011-2012页

作者： Sharon j.Brown Rafael j.yáñez-Muñoz Heidi R.Fuller School of Pharmacy and Bioengineering Keele UniversityKeeleUK Wolfson Center for Inherited Neuromuscular Disease TORCH BuildingRJAH Orthopaedic HospitalOswestryUK *** Center of Gene and Cell TherapyDepartment of Biological SciencesSchool of Life Sciences and the EnvironmentRoyal Holloway University of LondonEghamUK

Spinal muscular atrophy(SMA)is a genetic condition that results in selective lower motor neuron loss with concomitant muscle weakness and *** genetic cause of SMA was understood in 1995 when loss or impairment of the survival motor neuron 1(SMN1)gene was identified as the main contributing factor(Lefebvre et al.,1995).This,in combination with the discovery that humans have a“back-up”gene,SMN2,which can produce low levels(approximately 10%)of the full-length functional SMN protein,has led to the generation of SMA-specific gene *** was traditionally classified according to age of symptom onset and developmental milestones achieved,with life expectancy and severity varying between ***,SMN2 copy number is used as a proxy for the prediction of disease severity,with higher SMN2 copy number typically being associated with reduced severity of SMA,although this relationship is not absolute:some individuals with low SMN2 copy number have less severe SMA phenotypes and vice ***,the etiology of SMA is further complicated by other factors,such as non-typical nucleotide variants and SMN2-independent modifiers of disease severity.

关键词： atrophy traditionally absolute

Thermal stability of nanograins with grain boundary relaxation in microalloyed Cu-Sb and Cu-Fe

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journal of Materials Science & Technology 2023年第24期155卷 66-71页

作者： R.j. Zhu x.Zhou x.y. Li Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China

Grain refinement into nanoscale significantly enhances the strength and hardness of metallic materials but generally reduces the thermal stability by the introduced strong tendency for grain boundary(GB)*** nanograins through GB relaxation had been proven as an effective way in several metals recently when the grain size is below a critical ***,we discovered that the abnormally enhanced thermal stability induced by GB relaxation can be realized in 0.5%Sb or Fe doped Cu,similar to that in pure *** observed critical grain sizes for GB relaxation in the two Cu alloys are almost the same as pure ***,the GB relaxation effect on thermal stability is kind of suppressed compared to pure Cu with similar grain sizes because of the segregation/precipitation of Sb/Fe during the annealing process,which accelerates the detwinning and the failure of relaxed GBs.

关键词： Thermal stability Grain boundary relaxation Nanograined Cu alloy Segregation Precipitate

MODELING OF MICROSTRUCTURAL EVOLUTION IN MICROALLOyED STEEL DURING HOT FORGING PROCESS

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Acta Metallurgica Sinica(English Letters) 2006年第4期19卷 279-286页

作者： j. Wang j. Chen Z. Zhao x.y. Ruan National Die ＆. Mold CAD Engineering Research Center Shanghai Jiaotong University Shanghai 200030 China

The microstractural evolution of microalloyed steel during hot forging process was investigated using physical simulation experiments. The dynamic recrystallized fraction was described by modifying Avrami＇s equation, the parameters of which were determined by single hit compression tests. Double hit compression tests were performed to model the equation describing the static recrystallized fraction, and the obtained predicted values were in good agreement with the measured values. Austenitic grain growth was modeled as： Dinc^5 = D0^5 ＋ 1.6 × 10^32t·exp （ -716870/RT ） using isothermal tests. Furthermore, an equation describing the dynamic recrystallized grain size was given as Ddyn=3771·Z^-0.2. The models of microstructural evolution could be applied to the numerical simulation of hot forging.

关键词： microalloyed forging steel flow stress recrystallized fraction grain size

NUMERICAL INVESTIGATION ON FLOW CHARACTERISTICS IN RIBBED BEND

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journal of Hydrodynamics 2001年第2期13卷 111-120页

作者： yao, j. Fan, j.R. Zhang, x.y. Cen, K.F. Dept. of Energy Engineering Zhejiang Univ. Hangzhou 310027 China

Previous research by the author has proved that ribbed bend technology is a simple and efficient anti-erosion method. The present paper is a further study to unveil the mechanism of the technology by using numerical method. The flow characteristics in ribbed bend were studied. A k-Ε turbulence model was used and the simulations were carried out in the body-fitted coordinates. This procedure was confirmed to be credible by showing the satisfactory agreement between the predications and experimental results. It is concluded that the character of the longitudinal flow in ribbed bend especially in the concave parts between ribs has a beneficial effect on increasing the anti-erosion ability of ribbed bend but the secondary flow has little effect on determining the particle trajectory.

关键词： Boundary conditions Differential equations Erosion Mathematical models Numerical methods Three dimensional

First-principles Investigation of Bi Segregation at the Solder Interface of Cu/Cu_3Sn(010)

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journal of Materials Science & Technology 2010年第12期26卷 1057-1062页

作者： x.y. Pang Z.Q. Liu S.Q. Wang j.K. Shang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign IL 61801 USA

Density functional theory was employed to investigate the bismuth segregation at Cu/Cu3Sn（010） interface. Five initial constructions were introduced by adopting the adhesion energy criterion. Among them, the so-called ＂between-Cu＂ construction in which the interface Cu atoms of Cu slab locate along Cu-Cu bond direction in Cu3Sn slab was found to be the most energy-favored at an adhesion energy of 1.96 j/m^2. Based on this construction, five possible segregation sites were examined, and the most likely segregation site was determined with adhesion energy as low as 1.06 j/m^2, which was almost half of the initial one. Comparing with other sitest adhesion energies, it was concluded that size effect took a large part in embrittlement. The analyses of atomic structure and electronic density revealed that the slabs shifted away from interfaces due to bismuth segregation, and the atoms around Bi atom were Dressed away. This calculated work agreed aualitativelv with reported experimental results.

关键词： First-principles calculation Segregation Bismuth Interface SnBi solder

RELATIONSHIP AMONG EVAPORATION FLUx OF GROUNDWATER, DEPTH OF WATER TABLE AND NEGATIVE PRESSURE HEAD IN BARE SOIL

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journal of Hydrodynamics 2000年第4期12卷 52-58页

作者： Qian, j.Z. Zhu, x.y. Zhou, N.Q. Li, G.y. Dep. of Earth Sci. Nanjing Univ. Nanjing 210093 China

Evaporation of ground water is a part of moisture circulation in the field. And it is a main natural form in which water transmits from the ground water to the soil water and atmosphere water. According to the simulated experiments, we study the relationship among the evaporation, depth of groundwater table and negative pressure. By theoretical analysis of the experimental results, the main conclusions are drawn as follows. There are two abrupt points in every Q-H curve. The locations of the abrupt points are separately in step with the height of top of the capillary fringe and the height of maximal capillary rise in the soil section. When the depth of water table H is small, the evaporation flux of ground water is large. While the depth of water table exceeds the maximal capillary rise of media in vadose zone, the capillary rise breaks up and evaporation flux of groundwater is small. The water content ratio in ground surface tends to be zero and the surface of soil tends to be drought. These conclusions show that the maximal capillary rise of media in vadose zone is an important value in regulating rational depth of ground water to reduce the evaporation of ground water and to increase effective quantity of water resources. In the meantime, these conclusions are of important theoretical and practical significance to reduce the evaporation of ground water, to prevent and cure the salinization of soil, and to make full use of and protect water resources in the northern plains in China.

关键词： Capillarity Evaporation Soils

RHEOLOGy FEATURE OF SIMPLE METAL MELT

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 181-186页

作者： C.j. Sun H.R. Geng y.S. Shen x.y. Teng Z.x. yang Key Laboratory of Liquid Structure and Heredity of Materials Ministry of Education Shandong University Jinan 250061 China School of Material Science and Engineering Jinan University Jinan 250022 China

The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.

关键词： Newtonian liquid rheology melt Bi Sb

INFLUENCES OF CASTING SPEED AND SEN DEPTH ON FLUID FLOW IN THE FUNNEL TyPE MOLD OF A THIN SLAB CASTER

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 15-26页

作者： B.W. Li x.y. Tian E.G. Wang j.C. He Key Laboratory of National Education Ministry for Electromagnetic Processing of Materials Northeastern University Shenyang 110004 China

In recent years, thin slab continuous casting technology has been widely used to improve the quality of the product and to reduce the cost. One of the challenges faced by this technology is to design reasonable flow patterns, which strongly affect the surface and inner properties of the final slab in the mold. With the fixed scales and complex geometrical structures of nozzle and funnel type mold, a series of numerical simulations are made to analyze the flow patterns in melt steel using finite volume method based on structured body fitted coordinate grids. The CFD （computational fluid dynamics） package is validated first using one typical case described in previously published studies, and then it is developed to study the effect of operational parameters on fluid flow in thin slab caster. Two operational parameters, casting speed and SEN （submerged entry nozzle） depth, are mainly considered for numerical analysis. On the basis of present simulations, the reasonable SEN submergence depths corresponding to different casting speeds are suggested according to fluid flow characteristics like, flow jet impingement on the narrow side of the mold, flow speed of the melt steel beneath the meniscus and the recirculation region. This is the first stage of study on the numerical analysis of the whole thin slab casting process with electromagnetic brake.

关键词： continuous casting thin slab submerged entry nozzle (SEN) numerical analysis funnel type mold standard k-ε model RNG (renormalization group) k-ε model

Characterization of high-pressure die-cast hypereutectic Al-Si alloys based on microstructural distribution and fracture morphology

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journal of Materials Science & Technology 2019年第6期35卷 1099-1107页

作者： x.y. j.ao j. Wang C.F. Liu Z.P. Guo G.D. Tong S.L. Ma y. Bi y.F. Zhang S.M. xiong School of Materials Science and Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Automobile Safety and Energy Tsinghua University Beijing China China FAW Foundry Co. Ltd. Changchun 130011. China

The fracture behavior of high-pressure die-cast hypereutectic(HPDC) Al-Si alloys was investigated using a high-resolution laboratory CT and synchrotron x-ray tomography with a particular focus on the influence of HPDC microstructure. Results showed that microstructure of the alloy was mainly comprised of primary silicon particles(PSPs), Al dendrites, Cu-rich phases and pores. Most of the coarse PSPs, Cu-rich phases and pores were located in the center of the specimen. The rapid solidification of HPDC led to a heterogeneous microstructural feature. Elemental Cu was enriched in the frontiers of solid-liquid interface, causing the formation of large size dendritic arms. The pores were formed in the interdendrites which endured high stress intensity under high applied stress. Microcracks were originated from pores and further connected Cu-rich phases causing intergranular fracture. PSPs worked as obstacles causing piling-up dislocations in the phase interface. In the regions where large size of PSPs enriched in, PSPs ruptured rather than debonded from matrix, indicating transgranular fractures of PSPs. Microcracks originated around pores and PSPs tended to converge on the main cracks to decrease the energy required for crack propagation.

关键词： Hypereutectic Al-Si alloy Primary silicon particles Porosity Fracture morphology High pressure die casting

Observation of the y(4230)and a new structure in e^(+)e^(-)→K^(+)K^(-)j/Ψ

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Chinese Physics C 2022年第11期46卷 7-21页

作者： M.Ablikim M.N.Achasov P.Adlarson M.Albrecht R.Aliberti A.Amoroso M.R.An Q.An x.H.Bai y.Bai O.Bakina R.Baldini Ferroli I.Balossino y.Ban V.Batozskaya D.Becker K.Begzsuren N.Berger M.Bertani D.Bettoni F.Bianchi j.Bloms A.Bortone I.Boyko R.A.Briere A.Brueggemann H.Cai x.Cai A.Calcaterra G.F.Cao N.Cao S.A.Cetin j.F.Chang W.L.Chang G.Chelkov C.Chen G.Chen H.S.Chen M.L.Chen S.j.Chen T.Chen x.R.Chen x.T.Chen y.B.Chen Z.j.Chen W.S.Cheng x.Chu G.Cibinetto F.Cossio j.j.Cui H.L.Dai j.P.Dai A.Dbeyssi R.Ede Boer D.Dedovich Z.y.Deng A.Denig I.Denysenko M.Destefanis F.De Mori y.Ding j.Dong L.y.Dong M.y.Dong x.Dong S.x.Du P.Egorov y.L.Fan j.Fang S.S.Fang W.x.Fang y.Fang R.Farinelli L.Fava F.Feldbauer G.Felici C.Q.Feng j.H.Feng K Fischer M.Fritsch C.Fritzsch C.D.Fu H.Gao y.N.Gao yang Gao S.Garbolino I.Garzia P.T.Ge C.Geng E.M.Gersabeck A Gilman K.Goetzen L.Gong W.x.Gong W.Gradl M.Greco M.H.Gu C.y Guan A.Q.Guo L.B.Guo R.P.Guo y.P.Guo A.Guskov T.T.Han W.y.Han x.Q.Hao F.A.Harris K.K.He K.L.He F.H.Heinsius C.H.Heinz y.K.Heng C.Herold M.Himmelreich T.Holtmann G.y.Hou y.R.Hou Z.L.Hou H.M.Hu j.F.Hu T.Hu y.Hu G.S.Huang K.x.Huang L.Q.Huang L.Q.Huang x.T.Huang y.P.Huang Z.Huang T.Hussain N Husken W.Imoehl M.Irshad j.jackson S.jaeger S.janchiv Q.ji Q.P.ji x.B.ji x.L.ji y.y.ji Z.K.jia H.B.jiang S.S.jiang x.S.jiang y.jiang j.B.j.ao Z.j.ao S.jin y.jin M.Q.jing T.johansson N.Kalantar-Nayestanaki x.S.Kang R.Kappert M.Kavatsyuk B.C.Ke I.K.Keshk A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc W.Kuhn j.j.Lane j.S.Lange P.Larin A.Lavania L.Lavezzi Z.H.Lei H.Leithoff M.Lellmann T.Lenz C.Li C.Li C.H.Li Cheng Li D.M.Li F.Li G.Li H.Li H.Li H.B.Li H.j.Li H.N.Li j.Q.Li j.S.Li j.W.Li Ke Li L.j Li L.K.Li Lei Li M.H.Li P.R.Li S.x.Li S.y.Li T.Li W.D.Li W.G.Li x.H.Li x.L.Li xiaoyu Li Z.y.Li H.Liang H.Liang H.Liang y.F.Liang y.T.Liang G.R.Liao L.Z.Liao j.Libby A.Limphirat C.x.Lin D.x.Lin T.Lin B.j.Liu C.x.Liu D.Liu F.H.Liu Fang Liu Feng Liu G.M.Liu H.Liu H.M.Liu Huanhuan Liu Huihui Liu j.B.Liu j.L.Liu j.y.Liu K.Liu K.y.L Institute of High Energy Physics Beijing 100049China Beihang University Beijing 100191China Beijing Institute of Petrochemical Technology Beijing 102617China Bochum Ruhr-University D-44780 BochumGermany Carnegie Mellon University PittsburghPennsylvania 15213USA Central China Normal University Wuhan 430079China China Center of Advanced Science and Technology Beijing 100190China COMSATS University Islamabad Lahore CampusDefence RoadOff Raiwind Road54000 LahorePakistan Fudan University Shanghai 200433China G.I.Budker Institute of Nuclear Physics SB RAS(BINP) Novosibirsk 630090Russia GSI Helmholtzcentre for Heavy Ion Research GmbH D-64291 DarmstadtGermany Guangxi Normal University Guilin 541004China Hangzhou Normal University Hangzhou 310036China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University of Science and Technology Luoyang 471003China Henan University of Technology Zhengzhou 450001China Huangshan College Huangshan 245000China Hunan Normal University Changsha 410081China Hunan University Changsha 410082China Indian Institute of Technology Madras Chennai 600036India Indiana University BloomingtonIndiana 47405USA INFN Laboratori Nazionali di Frascati INFN Laboratori Nazionali di FrascatiI-00044FrascatiItaly INFN Laboratori Nazionali di Frascati INFN Sezione di PerugiaI-06100PerugiaItaly INFN Laboratori Nazionali di Frascati University of PerugiaI-06100PerugiaItaly INFN Sezione di Ferrara INFN Sezione di FerraraI-44122FerraraItaly INFN Sezione di Ferrara University of FerraraI-44122FerraraItaly Institute of Modern Physics Lanzhou 730000China Institute of Physics and Technology Peace Ave.54BUlaanbaatar 13330Mongolia jilin University Changchun 130012China johannes Gutenberg University of Mainz Johann-Joachim-Becher-Weg 45D-55099 MainzGermany joint Institute for Nuclear Research 141980 DubnaMoscow regionRussia justus-Liebig-Universitaet Giessen II.Physikalisches InstitutHeinrich-Buff-Ring 16

The cross sections of e^(+)e^(-)→K^(+)K^(-)j/Ψat center-of-mass energies from 4.127 to 4.600 GeV are measured based on 15.6 fb-1data collected with the BESⅢ detector operating at the BEPCⅡ storage *** resonant structures are observed in the line shape of the cross *** mass and width of the first structure are measured to be(4225.3±2.3±21.5)MeV and(72.9±6.1±30.8)MeV,*** are consistent with those of the established y(4230).The second structure is observed for the first time with a statistical significance greater than 8σ,denoted as y(4500).Its mass and width are determined to be(4484.7±13.3±24.1)MeV and(111.1±30.1±15.2)MeV,*** first presented uncertainties are statistical and the second ones are *** product of the electronic partial width with the decay branching fractionΓ(y(4230)→e^(+)e^(−))B(y(4230)→K^(+)K^(−)j/Ψ)is reported.

关键词： y states charmonium-like states BESⅢ