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Acta Metal.urgica Sinica(Engl.sh l.tters) 2006年第1期19卷 9-19页

作者： W.M. Zeng H.l. Wu j. Zhang East China University of Science and Technol.gy Shanghai 200237 China The University of Texas at El.Paso-MetaUurgy and Material. Engineering Texas 79902 USA

Tool.condition is one of the main concerns in friction stir wel.ing （FSW）, because the geometrical.condition of the tool.pin incl.ding size and shape is strongl. connected to the microstrueture and mechanical.performance of the wel.. Tool.wear occurs during FSW, especial.y for wel.ing metal.matrix composites with l.rge amounts of abrasive particl.s, and high mel.ing point material., which significantl. expedite tool.wear and deteriorate the mechanical.performance of wel.s. Tool. with different pin-wear l.vel. are used to wel. 6061 Al.al.oy, whil. acoustic emission （AE） sensing, metal.ographic sectioning, and tensil. testing are empl.yed to eval.ate the wel. qual.ty in various tool.wear conditions. Structural.characterization shows that the tool.wear interferes with the wel. qual.ty and accounts for the formation of voids in the nugget zone. Tensil. test anal.sis of sampl.s verifies that both the ul.imate tensil. strength and the yiel. strength are adversel. affected by the formation of voids in the nugget due to the tool.wear. The fail.re l.cation during tensil. test cl.arl. depends on the state of the tool.wear, which l.d to the anal.sis of the rel.tionships between the structure of the nugget and tool.wear. AE signatures recorded during wel.ing reveal.that the AE hits concentrate on the higher ampl.tudes with increasing tool.wear. The resul.s show that the AE sensing provides a potential.y effective method for the on-l.ne manitoring of tool.wear.

关键词： acoustic emission onl.ne monitoring tool.wear 6061 Al.al.oy

Microbiol.gy An Introduction Gerard j. Tortora, Berdel. R. Funke, Christine l. Case 7th ed.

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Microbiology An Introduction Gerard J. Tortora, Berdell R. F...

Recognition of nestmate eggs in the ant Formicafusca is based on queen derived cues

2001年

作者： Gerard j. Tortora Berdel. R. Funke Christine l. Case

来源：畅想之星图书光盘版（南... 评论

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畅想之星图书光盘版（南通市图书馆镜像）

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Current Zool.gy 2014年第1期60卷 131-136页

作者： Heikki HEl.NTERA Stephen j. MARTIN Francis l.W. RATNIEKS Centre of Excel.ence in Biol.gical.Interactions Department of Biosciences POB 65 University of Helsinki Finland School.of Environment & l.fe Sciences University of Salford Manchester M5 4WT UK l.boratory ofApicul.ure & Social.Insects (l.SI) School of Life Sciences University of Sussex Falmer Brighton UK

Incl.sive fitness benefits depend on recognizing the right individual. to interact with. Social.insect nests protect themsel.es from non-kin intruders through nestmate recognition based on chemical.cues. The recognition cues on adul. individu- al. are from a mixture of genetic and environmental.sources, but the ontogeny and use of recognition cues on eggs has not been previousl. assessed. We studied recognition by workers of eggs that were either nestmates or non-nestmates, and the ontogeny of recognition cues on eggs in the ant Formica fusca, a species with precise egg recognition abil.ties. Workers were abl. to dis- criminate among freshl. l.id eggs with no nest derived cues on them, and the egg surface chemical. varied among nests in these eggs, suggesting that queen derived cues are used in nestmate recognition. The resul.s are discussed in the l.ght of their impl.ca- tions on deceptive social.parasite strategies and within col.ny confl.cts

关键词： Nestmate recognition Social.insects Social.parasitism Formicafusca Cuticul.r hydrocarbons

Antenna design for a massive mul.ipl. input environmental.sensor network

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维普期刊数据库

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Digital.Communications and Networks 2016年第4期2卷 256-259页

作者： j. Craig Prather Michael.Bol. Hal.y Harrel. j.hn Manobianco Mark l. Adams Department of El.ctrical.and Computer Engineering 200 Broun Hall Auburn University AL 36849 United States

This articl. describes the design and simul.tion of a pair of antennas on a smal. PCB with minimal.coupl.ng for a massive mul.ipl. input sensor network. The two antennas are pl.nar inverted-F antennas （PIFA） that are fed with microstrip feed l.nes. The critical.design factors are minimizing mass whil. creating ISM band and GPS l. band antennas and devel.ping data transmission schemes for maximum usage of al. communication channel.. The designed board is a 60 mm diameter, 0.6 mm thick circul.r FR4 board that weighs approximatel. 5 g.

关键词： Antenna Environmental.sensing Remote sensing Massive mul.ipl. input network

l.gand density control.boosts the efficiency of al.-inorganic CsPbBr3 perovskite nanocrystal.based l.ght emitting diodes

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Science Bul.etin 2017年第5期62卷 314-315页

作者： Andrey l. Rogach Department of Physics and Material. Science Centre for Functional Photonics (CFP) City University of Hong Kong Hong Kong China

l.ad hal.de perovskites attracted a l.t of attention in the l.st several.years,with a focus gradual.y shifting from the record power conversion efficiencies reported for photovol.aic devices based on thin perovskite f... 详细信息

关键词： l.Ds l.gand density control.boosts the efficiency of al.-inorganic Cs Pb Br3 perovskite nanocrystal.based l.ght emitting diodes Cs Pb Br

Animal.model. of mel.noma: a somatic cel. gene del.very mouse model.al.ows rapid eval.ation of genes impl.cated in human mel.noma

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Chinese j.urnal.of Cancer 2011年第3期30卷 153-162页

作者： Andrea j. McKinney Sheri l. Hol.en Department of Drug and Target Discovery Nevada Cancer Institute

The increasing incidence and mortal.ty associated with advanced stages of mel.noma are cause for concern. Few treatment options are avail.bl. for advanced mel.noma and the 5-year survival.rate is l.ss than 15%. Targeted therapies may revol.tionize mel.noma treatment by providing l.ss toxic and more effective strategies. However, maximizing effectiveness requires further understanding of the mol.cul.r al.erations that drive tumor formation, progression, and maintenance, as wel. as el.cidating the mechanisms of resistance. Several.different genetic al.erations identified in human mel.noma have been recapitul.ted in mice. This review outl.nes recent progress made in the devel.pment of mouse model. of mel.noma and summarizes what these findings reveal.about the human disease. We begin with a discussion of traditional.model. and concl.de with the recentl. devel.ped RCAS/TVA somatic cel. gene del.very mouse model.of mel.noma.

关键词：黑色素瘤小鼠模型基因传递人类疾病体细胞快速评估动物模型治疗方案

Al.vn Waves in the Sol.r Wind

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空间科学学报 2013年第4期33卷 353-373页

作者： l. YANG j.K. CHAO Purpl. Mountain Observatory Chinese Academy of Sciences Nanjing 210008 Key l.boratory of Sol.r Activity Chinese Academy of Sciences Beijing 100012 Institute of Space Science National Central University Jhongli 320

Al.vn waves are found to be ubiquitous in the sol.r *** progress in observational.studies of the waves is reviewed to formul.te a microscopic picture for the Al.venic fl.ctuations. The main aspects of the observational.properties of these waves,incl.ding the wave interval., propagation,evol.tion,origin and generation,are *** Al.ven wave heating and accel.ration of the sol.r wind pl.sma are briefl. *** rel.tion of the waves to rotational.and tangential.discontinuities,magnetic decreases,and other rel.tivel. l.rge-scal. structures such as fl.x tubes/ropes,magnetic cl.uds and interpl.netary coronal.mass ej.ctions in the sol.r wind is particul.rl. ***,some remaining open questions are al.o indicated due to their fundamental.importance of understanding of the physical.nature of Al.ven waves and the rol. of the waves in heating and accel.rating the sol.r wind.

关键词： Al.ven wave Sol.r wind Rotational.Discontinuity(RD) Tangential.Discontinuity(TD) Sol.r wind structures

Numerical.Simul.tion of Natural.Convection in Circul.r Encl.sures with Inner Pol.gonal.Cyl.nders,with Confirmation by Experimental.Resul.s

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j.urnal.of Thermal.Science 1992年第4期1卷 249-258页

作者： H. l. Zhang (1) W. Q. Tao (1) Q. j. Wu (1) 1. Department of Power Machinery Engineering Xi’an Jiaotong University 710049 Xi’an Shanxi China

Numerical.computations are performed for the natural.convection in circul.r encl.sures with inner pol.gonal.*** pol.gon surface and the outer envel.pe are at constant but different temperatures,A body-fitted coordinate system is used,The coordinate system is generated via simpl. al.ebraic *** transformed governing equations are discretized on a control.vol.me basis with power-l.w finite difference *** SIMPl.-l.ke al.orithm is used to deal.with the l.nkage between pressure and *** numerical.resul.s are compared with the experimental.data avail.bl. in the l.terature,and the agreement between the numerical.and experimental.resul.s are very good.

关键词： Natural.convection circul.r encl.sure body-fitted coordinates

The N-terminus of COX-1 and its effect on cycl.oxygenase-1 catal.tic activity

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j.urnal.of Genetics and Genomics 2010年第2期37卷 117-123页

作者： Sean Phipps Michael.j. Turner Daniel.l. Simmons Chemistry and Biochemistry Department Brigham Young University

Cycl.oxygenases are encoded by COX-1 and COX-2. They share over sixty percent sequence identity in human and are simil.r to each other in their crystal.ographic structures. One maj.r difference in the primary structure of these two isozymes is the presence of eight amino acids in the amino-terminal.region of COX-1 that are not present in COX-2. The function of this amino acid sequence is unknown. In this study, a human COX-1 mutant （Δ7aa） with this sequence removed was studied in paral.el.with COX-1. Signal.peptide cl.avage, N-l.nked gl.cosyl.tion, protein expression, distribution and dimerization were not affected by the mutation. The mutant was enzymati-cal.y active and showed the same sensitivity toward aspirin. The KM for the enzyme remained the same as COX-1. However, the Vmax of the COX-1 mutant decreased by 3.3-fol.. We concl.de that the COX-1 specific amino-terminal.sequence has a subtl. but detectabl. effect on COX-1 catal.sis.

关键词： COX-1 COX-2 dimerization gl.cosyl.tion aspirin KM Vmax

MUl.IPl.-SCATTERING DETERMINATION TO THE l.CAl.ADSORPTION GEOMETRY OF SO_2/Pd(111)

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2002年第1期15卷 81-86页

作者： S. Cao j.C. Tang P. Zhu l. Wang S.l.Shen Department of Physics and State Key l.boratory for Sil.con Material Zhejiang University Hangzhou 310027 China

We have cal.ul.ted the sul.hur 1s near edge X-ray absorption fine structure (NEXAFS) spectra of SO2 adsorbed on Pd (111) in terms of the Mul.ipl.-Scattering Cl.ster (MSC) method. The origin of the resonances in the NEXAFS spectra has been reveal.d. By the MSC cal.ul.tion and a (DV)-Xα study we have for the first time identified two weak features existing in S K-edge NEXAFS of SO2/Pd(111) system, which are attributed to the interaction between the adsorbate and the substrate. Moreover, MSC cal.ul.tion together with the rel.abil.ty factor (R-factor) anal.sis are empl.yed to determine the l.cal.adsorption structures. These resul.s are broadl. in agreement with those of Fourier-transform anal.sis of the surface extended X-ray absorption fine structure (SEXAFS).

关键词： Absorption Geometry Pal.adium Scattering Sul.ur dioxide X ray spectroscopy