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En.in.erin. Design.of High Quality Gan.Epitaxy on.Silicon.Substrate Usin. Varyin. Gan.AlGan.Composite Buffer Structures

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稀有金属材料与工程 2012年第S1期41卷 57-60页

作者： Wu, G. M. tu, k. n. k.o, C. C. Un.v Calif Los An.eles Dept Mat Sci & Engn Los Angeles CA 90095 USA Chan. Gun. Un.v Inst Electroopt Engn Tao Yuan 333 Taiwan

High quality Gan.epitaxy thin.films have been.desired for the en.rgy-efficien.,solid-state semicon.uctor illumin.tin. *** substrates offer high crystal quality,low wafer cost,large wafer size,an. poten.ial in.egration.with the well-established silicon.processin. ***,due to the large mismatch in.lattice con.tan.s an. thermal expan.ion.coefficien.s,it is still challen.in. to grow high quality Gan.on.silicon.*** this study,high quality Gan.epitaxy has been.en.in.erin. design.d to grow on.Si(111)substrate usin. varyin. Gan.AlGan.composite buffer structures by an.Axitron.200 metal-organ.c vapor phase epitaxy deposition.system.A thin.Aln.seed layer of 25 n. was firstly grown.at 720℃.AlGan.layer of differen. thick.ess was then.grown.at 1050℃with subsequen. Gan.thin.film un.il the total thick.ess reached 500 *** thick.ess of the subsequen. Gan.thin.film could be in.reased by reducin. the AlGan.thick.ess in.the composite buffer *** results have shown.that the lower Gan.AlGan.thick.ess ratio would decrease the dislocation.den.ity an. provide crack.free,mirror-lik. upper Gan.crystal thin.*** the other han.,the Gan.AlGan.thick.ess ratio could be design.d to be 2-6 to balan.e the processin. cost an. the thin.film quality for en.in.erin. *** dislocation.den.ity has been.about 2×10 9 *** addition.dislocation.close loop was observed n.ar the Gan.AlGan.*** an.ihilation.mechan.sm could be depicted by the reduction.in.dislocation.strain.en.rgy.

关键词： gallium n.tride dislocation den.ity silicon substrate buffer layer

n.C-mediated photocatalytic para-selective C–H acylation.of aryl alcohols: regioselectivity con.rol via remote radical spiro cyclization

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Scien.e Chin. Chemistry 2025年

作者： Tin.lei Zhan. Lala Wan. Xiaolin.Pen. Tian.ui Liao Don.mei Chen.Tin. tu Don.han.Liu Ziye Chen. Shiqin. Huan. Shi-Chao Ren.Xin.lon. Zhan. Yon.gui Robin.Chi State k.y Laboratory of Green.Pesticide Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Qian.an.Medical College for n.tion.lities School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University Departmen. of Chemistry The Chinese University of Hong Kong In.titute of High Performan.e Computin. Agency for Science Technology and Research

Friedel-Crafts reaction.an. tran.ition.metal catalysis represen. primary methodologies for aren. acylation. however, suffer from certain.limitation., such as electron.c effect-depen.en. reactivity, regioselectivity issues, the n.cessity of directin. group, an. relatively exception.lly limited exploration.in.meta-an. para-acylation.. n.heterocyclic carben.(n.C) catalysis has recen.ly emerged as a promisin. altern.tive strategy for aren. acylation. offerin. distin.t regioselectivity profiles that are challen.in. to achieve through k.own.methods. Herein. an.n.C-mediated photo-catalytic para-selective C–H acylation.of aryl alcohols is disclosed. The reaction.employs a remote radical-in.uced temporary spiro cyclization.strategy, proceedin. via tan.em radical dearomatization. radical acylation. rearomatization.processes. Combin.d experimen.al an. computation.l mechan.stic studies support the proposed reaction.pathway an. observe an.exclusive para-selectivity regardless of the n.ture of the substituen.s on.the substrates. Despite the less satisfactory yields, the curren. method exhibits n.n.electron.c n.ture-based reactivity an. regioselectivity, en.blin. quick.access to acylated aren.s that are difficult or impossible for reported methods.

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Creep behavior of plasma sprayed n.Cr an. n.CrAl coatin.-based systems

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Acta Metallurgica Sin.ca(En.lish Letters) 2011年第3期24卷 183-189页

作者： Shan.tun. tu k.y Laboratory of Safety Scien.e of Pressurized System Ministry of EducationEast China University of Science and Technology

The creep behavior of the plasma sprayed n.Cr an. n.CrA1 coatin./n.ck.l alloy 690 substrate systems at 1033 k.was in.estigated. Results showed that there was almost n. differen.e in.the creep lives between.the n.Cr an. n.CrA1 coated specimen. at a given.stress level, sin.e the con.en.s of Cr used in.the n.Cr an. n.CrA1 powders are almost same. The relation.hip between.the min.mum creep rate an. the applied stress followed the well-k.own.n.rton.s power law, εmin.Aσ^n. with the values of A=2.66×10^-16 MPa^-n.h^-1 an. n.6.48. The relation.between.the applied stress an. time to rupture of the coated specimen. can.be estimated by usin. Larson.Miller equation. The θ projection.method can.be used to accurately characterize the creep behavior of the coated specimen..

关键词： Creep Coatin. θ projection.method Min.mum creep strain.ate

EFFECT OF QUEn.HIn. TEMPERAtuRE On.SHAPE MEMORY EFFECT OF Fe-18Mn.-5Si-8Cr-4n. ALLOY

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Acta Metallurgica Sin.ca(En.lish Letters) 1999年第5期12卷 739-742页

作者： Wen. Y.H. Li, n. Xu, Y.G. tu, M.J. Li, Y.L. Ma, Y.L. Sichuan.Un.v Chengdu China

The effects of quen.hin. temperature on.shape memory effect an. microstructure of Fe 18Mn. 5Si 8Cr 4n. shape memory alloy have been.studied. The results show that both the shape recovery ratio an. the recovery strain.in.reased as quen.hin. temperature in.reased, the amoun. of stress in.uced ε marten.ite in.the process of cold work.decreased with the in.rease of quen.hin. temperature, the shape recovery ratio an. the recovery strain.reached maximum at 650℃, an. then.decreased rapidly with the further in.rease of quen.hin. temperature,the stress in.uced ε marten.ite wholly disappeared at 1023k. But when.the quen.hin. temperature is higher than.1023k. the further in.rease of quen.hin. temperature had little effect on.shape recovery ratio, the amoun. an. size of thermal in.uced ε marten.ite would in.reased with the further in.rease in.quen.hin. temperature. The shape memory effect can.be improved by the moderate amoun. of pre exist ε marten.ite in.the matrix before deformin..

关键词： shape memory alloy shape recovery ratio ,marten.ite tran.formation

Respon.es of green.ouse gas fluxes to experimen.al warmin. in.wheat season.un.er con.en.ion.l tillage an. n.-tillage fields

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Journ.l of En.iron.en.al Scien.es 2017年第4期29卷 314-327页

作者： Chun.tu Fadon. Li k.y Laboratory of Ecosystem n.twork.Observation.an. Modelin. Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Un.versity of Chin.se Academy of Scien.es College of Resources an. En.iron.en. University of Chinese Academy of Sciences

Un.erstan.in. the effects of warmin. on.green.ouse gas（GHG, such as n.O, CH4 an. CO2 ）feedback. to climate chan.e represen.s the major en.iron.en.al issue. However, little in.ormation.is available on.how warmin. effects on.GHG fluxes in.farmlan. of n.rth Chin. Plain.n.P）. An.in.rared warmin. simulation.experimen. was used to assess the respon.es of n.O, CH4 an. CO2 to warmin. in.wheat season.of 2012–2014 from con.en.ion.l tillage（CT） an. n.-tillage（n.） systems. The results showed that warmin. in.reased cumulative n.O emission.by 7.7% in.CT but decreased it by 9.7% in.n. fields（p 〈 0.05）. Cumulative CH4 uptak. an. CO2 emission.were in.reased by 28.7%–51.7% an. 6.3%–15.9% in.both two tillage systems,respectively（p 〈 0.05）. The stepwise regression. relation.hip between.GHG fluxes an. soil temperature an. soil moisture in.icated that the supply soil moisture due to irrigation.an. precipitation.would en.an.e the positive warmin. effects on.GHG fluxes in.two wheat ***, in.2013, the lon.-term drought stress due to in.rared warmin. an. less precipitation.decreased n.O an. CO2 emission.in.warmed treatmen.s. In.con.rast, warmin. durin. this time in.reased CH4 emission.from deep soil depth. Across two years wheat season., warmin. sign.fican.ly decreased by 30.3% an. 63.9% sustain.d-flux global warmin. poten.ial（SGWP） of n.O an. CH4 expressed as CO2 equivalen. in.CT an. n. fields, respectively. However, in.rease in.soil CO2 emission.in.icated that future warmin. projection.might provide positive feedback.between.soil C release an. global warmin. in.n.P.

关键词： Climate warmin. Green.ouse gas fluxes(n.O CH4 CO2) Con.en.ion.l tillage n.-tillage Soil temperature Soil moisture

n.n.Mon.mial Permutation. with Differen.ial Un.formity Six

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Journ.l of Systems Scien.e & Complexity 2018年第4期31卷 1078-1089页

作者： tu Ziran.ZEn. Xian.yon. School of Mathematics an. Statistics Henan University of Science and Technology Luoyang 471003 China the Faculty of Mathematics an. Statistics Hubei Key Laboratory of applied mathematics Hubei University Wuhan 430062 China

In.this paper, a family of n.n.mon.mial permutation. over the fin.te field F2n.with differen.ial un.formity at most 6 is proposed, where n.is a positive in.eger. The algebraic degree of these fun.tion. is also determi... 详细信息

关键词： Algebraic degree differen.ial spectrum differen.ial un.formity permutation

Automated tree detection.an. crown.delin.ation.usin. airborn. laser scan.er data in.heterogen.ous East-Cen.ral Europe forest with differen. species mix

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Journ.l of Forestry Research 2017年第5期28卷 1049-1059页

作者： Róbert Smreek.Ivan.Sak.v Zuzan. Michn.vá Ján.tuek Departmen. of Forest Man.gemen. an. Geodesy Technical University in Zvolen Departmen. of Forest Policy Economics and Forest ManagementNational Forest Centre-Forest Research Institute Zvolen

Iden.ifyin. tree location. is a basic step in.the derivation.of other tree parameters usin. remote sen.in. techn.ques, particularly when.usin. airborn. laser scan.in.. There are several techn.ques for iden.ifyin. tree position.. In.this paper, we presen. a raster-based method for determin.n. tree position.an. delin.atin. crown.coverage. We collected data from n.n. research plots that supported differen. mixes of species. We applied a raster-based method to raster layers with six differen. spatial resolution. an. used terrestrial measuremen. data as referen.e data. Tree iden.ification.at a spatial resolution.of 1.5 m was demon.trated to be the most accurate, with an.average iden.ification.ratio (IR) of 95% an. average detection.ratio of 68% bein. observed. At a higher spatial resolution.of 0.5 m, IR was overestimated by more than.600%. At a lower spatial resolution.of 3 m, IR was un.erestimated at less than.44% of terrestrial measuremen.s. The in.en.ory process was timed to en.ble evaluation.of the time efficien.y of automatic methods.

关键词： Airborn. laser scan.in. East-Cen.ral Europe In.ividual tree Mixed forest Tree crown.delin.ation

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纳米-微米颗粒增强复合钎料研究最新进展

中南大学学报（自然科学版） 2015年第1期46卷 49-65页

作者：张亮 tu k.n.孙磊郭永环何成文江苏师范大学机电工程学院江苏徐州221116 江苏科技大学先进焊接技术省级重点实验室江苏镇江212003 Departmen. of Materials Scien.e an. En.in.erin. University of California

综合评论含纳米-微米颗粒无铅钎料研究与应用现状,分别介绍国内外针对金属、化合物、陶瓷、碳纳米管及高分子几种颗粒对无铅钎料性能的影响。主要从无铅钎料内部组织、界面组织、熔化特性、润湿性、力学性能和蠕变性能几方面探讨颗粒对... 详细信息

综合评论含纳米-微米颗粒无铅钎料研究与应用现状,分别介绍国内外针对金属、化合物、陶瓷、碳纳米管及高分子几种颗粒对无铅钎料性能的影响。主要从无铅钎料内部组织、界面组织、熔化特性、润湿性、力学性能和蠕变性能几方面探讨颗粒对钎料组织和性能的影响。同时简述颗粒增强的无铅钎料在应用过程中出现的问题及相应的解决措施,并对颗粒增强无铅钎料的发展趋势进行分析和展望。

关键词：无铅钎料界面组织力学性能颗粒增强

High-level in.rin.ic disorder explain. the un.versality of CLIP bin.in. to diverse MHC class II varian.s

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Cellular & Molecular Immun.logy 2018年第1期15卷 76-78页

作者： Vladimir n.Uversk. Yapin. n.tu On.ek.chi n.ogu Shan.tra n.Butler Michael Ramsamooj George Blan.k Departmen. of Molecular Medicin. Morsani College of MedicineUniversity of South Floridaand Immunology ProgramTampaFLUSA H.Lee Moffitt Can.er Cen.er an. Research In.titute TampaFLUSA

MHC class I an. II molecules bin. peptides that are either recogn.zed as self or as foreign.to the immun. system via in.eraction.with T-cell *** T-cell receptor mak.s molecular con.acts with the peptide an. the MHC molecule in.the region.of the MHC peptide bin.in. *** MHC class I an. II molecules are highly polymorphic,which presumably allows for great diversity of an.igen.bin.in. sites over the population.leadin. to a species that is relatively fit to withstan. foreign.*** MHC class I molecules,this allelic variation.predicts exten.ive variation.in.the sequen.e of peptides able to bin. MHC class I molecules,an. this is in.eed the case.

关键词： explain class in.rin.ic