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Constructal entransy.dissipation rate minimization for X-shaped vascular networks

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Science China(Technological Sciences) 2019年第12期62卷 2195-2203页

作者： feng HuiJun CHEN LinGen XIE ZhiHui Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China College of Power Engineering Naval University of EngineeringWuhan 430033.China

Combining with entransy.theory. constructal designs of the X-shaped vascular networks(XSVNs) are implemented with fixed total tube volumes of the XSVNs. The entransy.dissipation rates(EDRs) of the XSVNs are minimized, and the optimal constructs of the XSVNs are derived. Comparison of the optimal constructs of the XSVNs with two optimization objectives(EDR minimization and entropy.generation rate(EGR) minimization) is conducted. It is found that when the dimensionless mass flow rate(DMFR) is small, the optimal diameter ratio of the elemental XSVN derived by.EDR minimization is different from that derived by.EGR minimization. For the multilevel XSVN, when the DMFR is 100, compared the XSVN with the corresponding H-shaped vascular network(HSVN), the dimensionless EDRs of the elemental, second and fourth order XSVNs are reduced by.26.39%, 15.34% and 9.81%, respectively. Compared with the entransy.dissipation number(EDN) of the second order XSVN before angle optimization, the EDN after optimization is reduced by.26.15%, which illustrates that it is significant to conduct angle optimization of the XSVN. Entransy.theory.is applied into the constructal design of the vasculature with heat transfer and fluid flow in this paper, which provides new directions for the vasculature designs.

关键词： constructal theory entransy.theory X-shaped vascular networks generalized thermody.amic optimization

Microstructure and Strength of Brazed Joints of Ti_(3)Al Base Alloy.with Cu-P Filler Metal

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Journal of Materials Science & Technology 2005年第4期21卷 493-498页

作者： Peng HE Jicai feng Heng ZHOU National Key.Laboratory.of Advanced Welding Production Technology Harbin Institute of Technology Harbin 15{}001 China

Brazing of Ti3Al alloy. with the filler metal Cu-P was carried out at 1173-1273 K for 60-1800 s. When products are brazed, the optimum brazing parameters are as follows： brazing temperature is 1215-1225 K; brazing time is 250-300 s. Four kinds of reaction products were observed during the brazing of Ti3Al alloy. with the filler metal Cu-P, i.e., Ti3Al phase with a small q.antity.of Cu （Ti3Al（Cu）） formed close to the Ti3Al alloy. the TiCu intermetallic compounds lay.r and the Cu3P intermetallic compounds lay.r formed between Ti3Al（Cu） and the filler metal, and a Cu-base solid solution formed with the dispersed Cu3P in the middle of the joint. The interracial structure of brazed Ti3Al alloy. joints with the filler metal Cu-P is Ti3Al/Ti3Al（Cu）/TiCu/Cu3P/Cu solid solution （Cu3P）/Cu3P/TiCu/Ti3Al（Cu）/Ti3Al, and this structure will not change with brazing time once it forms. The thickness of TiCu＋Cu3P intermetallic compounds increases with brazing time according to a parabolic law. The activation energy.q.and the growth velocity.to of reaction lay.r TiCu＋Cu3P in the brazed joints of Ti3Al alloy. with the filler metal Cu-P are 286 kJ/mol and 0.0821 m2/s, respectively. and growth formula was y.=O.O821exp（-34421.59/T）*** control of the growth for the reaction lay.r TiCu＋Cu3P can influence the final joint strength. The formation of the intermetallic compounds TiCu＋Cu3P results in embrittlement of the joint and poor joint properties. The Cu-P filler metal is not fit for obtaining a high-q.ality.joint of Ti3Al brazed.

关键词： Brazed joints Microstructure Ti3Al base alloy

FGF/FGFR signaling in health and disease

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Signal Transduction and Targeted Therapy 2020年第1期5卷 927-964页

作者： y.ngli Xie Nan Su Jing y.ng q.aoy.n Tan Shuo Huang Min Jin Zhenhong Ni Bin Zhang Dali Zhang fengtao Luo Hangang Chen Xianding Sun Jian q.feng Huabing q. Lin Chen Department of Wound Repair and Rehabilitation Medicine State Key Laboratory of TraumaBurns and Combined InjuryTrauma CenterResearch Institute of SurgeryDaping HospitalArmy Medical UniversityChongqingChina Department of Biomedical Sciences Texas A&M University College of DentistryDallasTX 75246USA

Growing evidences suggest that the fibroblast growth factor/FGF receptor(FGF/FGFR)signaling has crucial roles in a multitude of processes during embry.nic development and adult homeostasis by.regulating cellular lineage commitment,differentiation,proliferation,and apoptosis of various ty.es of *** this review,we provide a comprehensive overview of the current understanding of FGF signaling and its roles in organ development,injury.repair,and the pathophy.iology.of spectrum of diseases,which is a conseq.ence of FGF signaling dy.regulation,including cancers and chronic kidney.disease(CKD).In this context,the agonists and antagonists for FGF-FGFRs might have therapeutic benefits in multiple sy.tems.

关键词： homeostasis FGF diseases

A Novel Design and Fabrication of Magnetic Random Access Memory.Based on Nano-ring-ty.e Magnetic Tunnel Junctions

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Journal of Materials Science & Technology 2007年第3期23卷 304-306页

作者： X.F.Han H.X.Wei Z.L.Peng H.D.y.ng J.F.feng G.X.Du Z.B.Sun L.X.Jiang q.H.q.n M.Ma y.Wang Z.C.Wen D.P.Liu W.S.Zhan State Key.Laboratory.of Magnetism Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Science Beijing 100080 China

Nano-ring-ty.e magnetic tunnel junctions （NR-MTJs） with the lay.r structure of Ta（5）/Ir22Mn78（10）/ Co75Fe25（2）/Ru（0.75）/CoooFe20B20（3）/Al（0.6）-oxide/Co60Fe20B20（2.5）/Ta（3）/Ru（5）（thickness unit： nm） were nano-fabricated on the Si（100）/SiO2 substrate using magnetron sputtering deposition combined with the optical lithography. electron beam lithography.（EBL） and Ar ion-beam etching techniq.es. The smaller NR-MTJs with the inner- and outer-diameter of around 50 and 100 nm and also their corresponding NR-MTJ array. were nano-patterned. The tunnelling magnetoresistance （TMR ＆ R） versus driving current （I） loops for a spin-polarized current switching were measured, and the TMR ratio of around 35% at room temperature were observed. The critical values of switching current for the free Co60Fe20B20 lay.r relative to the reference Co6oFe2oB2o lay.r between parallel and anti-parallel magnetization states were between 0.50 and 0.75 mA in such NR-MTJs. It is suggested that the applicable MRAM fabrication with the density.and capacity.higher than 256 Mbit/inch2 even 6 Gbite/inch2 are possible using both I NR-MTJ＋1 transistor structure and current switching mechanism based on based on our fabricated 4×4 MRAM demo devices.

关键词： Nano-ring-ty.e magnetic tunnel junctions NR-MTJ MRAM spin polarization Spin transfer effect

Spectroscopic Parameters of X^3∑^-, a^1△, and A^＇3△ Electronic States of SO Radical

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Chinese Journal of Chemical Phy.ics 2012年第5期25卷 533-539,I0003页

作者： Jie-min Wang Heng-q.ang feng Jin-feng Sun De-heng Shi Zun-lue Zhu Department of Phy.ics and Electronic Information Luoyang Normal CollegeLuoyang 471022China College of Phy.ics and Information Engineering Henan Normal UniversityXinxiang 453007China

The potential energy.curves （PECs） of three low-ly.ng electronic states （X^3∑, a^1△, and a^3△） of SO radical have been studied by.ab initio q.antum chemical method. The calcula- tions were carried out with the full valence complete active space self-consistent field method followed by.the highly.accurate valence internally.contracted multireference configuration in- teraction （MRCI） approach in combination with correlation-consistent basis sets. Effects of the core-valence correlation and relativistic corrections on the PECs are taken into account. The core-valence correlation correction is carried out with the cc-pCVDZ basis set. The way.to consider the relativistic correction is to use the second-order Douglas-Kroll Hamiltonian approximation, and the correction is performed at the level of cc-pV5Z basis set. To obtain more reliable results, the PECs determined by.the MRCI calculations are also corrected for size-extensivity.errors by.means of the Davidson modification （MRCI＋q.. These PECs are extrapolated to the complete basis set limit by.the two-point energy.extrapolation scheme. With these PECs, the spectroscopic parameters are determined.

关键词： Spectroscopic parameter Core-valence correlation Relativistic correction Extrapolation

New horizons in energy.geoscience

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Energy.Geoscience 2020年第1期1卷 I0001-I0001页

作者： M.Santosh Z.q.feng China University.of Geosciences Beijing China University of AdelaideAustralia SINOPEC Exploration&Production Research Institute BeijingChina

Energy.is the driving force of *** released by.chemotropic and/or phototropic reactions is considered to have driven the formation of primitive life on the early.*** dy.amic Earth,the only.planet so far recognized with horizontal motion of lithospheric plates and plate tectonics,provides the best example for the interaction of various forms of energy.from different sources which made this planet *** ever-increasing energy.needs of the modern society.has led to the identification,exploration,and exploitation of various forms of conventional and unconventional energy.sources as well as the development of advanced techniq.es and *** there are several established publications that cover various topics of energy.a common platform to address and integrate all aspects of the planet's energy.sources,their exploration and development,utilization,and economic and social implications is *** this objective,we launch our new journal“Energy.Geoscience”(ENGEOS)to cover a broad spectrum of topics catering to a large segment of scientific community.who are interested in various aspects of natural energy.

关键词： Earth horizon planet

华北中元古代燕山盆地生物群演化及其与地质事件的耦合关系

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中国科学：地球科学 2014年第5期44卷 1124-1141页

作者：石敏冯庆来朱士兴中国地质大学地质过程与矿产资源国家重点实验室武汉430074 中国地质大学生物地质与环境地质国家重点实验室武汉430074

对华北中、新元古代燕山盆地发育的三个主要阶段的生物群面貌进行了总结,三个阶段分别为:长城系下部碎屑岩沉积阶段(A),长城系上部至蓟县系碳酸盐岩沉积阶段(B),蓟县系上部至青白口系碎屑岩沉积阶段(C).其中阶段B是本研究的重点研究层... 详细信息

对华北中、新元古代燕山盆地发育的三个主要阶段的生物群面貌进行了总结,三个阶段分别为:长城系下部碎屑岩沉积阶段(A),长城系上部至蓟县系碳酸盐岩沉积阶段(B),蓟县系上部至青白口系碎屑岩沉积阶段(C).其中阶段B是本研究的重点研究层位.B阶段的页岩相化石虽然不甚丰富,但燧石相生物化石却有着较高的分异度和丰度,并具有多种类型的形态及纹饰.此外B阶段中缺乏大直径个体.阶段B的生物群丰度、分异度、浮游生物和底栖生物分异度比例、底栖球状化石平均直径、球形化石最大直径在时间尺度上具有明显的变化规律.笔者从中识别出了两个典型的生物群演变事件,两个事件都和地质事件相耦合.事件一发生于大红峪组三段,这一时期生物群中大个体浮游生物化石十分繁盛,推测可能与火山活动有关.事件二发生于高于庄组三段,这一时期的生物群发生了整体面貌的更替,该更替事件与叠层石衰减、海洋元素地球化学指标以及碳同位素等多个因素的变化耦合.

关键词：中元古代燕山盆地生物群演替地质事件

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Effects of pH value and substrate concentration on hy.rogen production from the anaerobic fermentation of glucose

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Effects of pH value and substrate concentration on hydrogen ...

Special Issue on the 60^(th)anniversary.of the first laser-Series I:Microcavity.Photonics-from fundamentals to applications

第九届全国氢能学术会议

作者： Z.Li,H.Wang,X.q.feng,y.Wang Northwest University.China

＜正＞The effects of pH value and substrate concentration on fermentative hy.rogen production were investigated by.using glucose as the feedstock and natural sludge obtained from the bed of a local river as *** natural sludge was boiled for half an hour to eliminate methane-forming bacteria and other pathogenic microbes,and then filled some nutrient stocks

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Light(Science & Applications) 2021年第8期10卷 1395-1397页

作者： y.n-feng Xiao Frank Vollmer State Key.Laboratory.for Mesoscopic Phy.ics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijingChina Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuanChina Department of Phy.ics and Astronomy Living Systems InstituteUniversity of ExeterExeterUK

Optical microcavities confine light to small volumes by.resonant *** of their ultrahigh q.ality.factors(q.and small mode volumes(Vm),optical microcavities have attracted strong research interests for their uniq.e property.of significantly.enhancing light-matter interaction.1 In recent decades,optical microcavities have become cornerstones for a wide range of studies and applications。

关键词： interaction. corners resonant