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Topsoil as Af.ected by Dung Deposition Under Resting Places of.Red Howler Monkey (Alouatta seniculus)

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Pedosphere 2008年第6期18卷 691-698页

作者： S. POUVELLE f. f.ER j. f. PONGE Musum National d'Histoire Naturelle CNRS UMR 7179 4 avenue du Petit-Chateau

The short-term inf.uence of.dung deposition and the f.rther redistribution of.dung by dung beetles were studied under a resting place of.the red howler monkey （Alouatta seniculus） living in tropical ralnf.rests of.South America. Monkey dung was experimentally clumped on the f.eld in a place used by troops of.howler monkeys f.r resting in the Nouragues Reserve Station, f.ench Guiana. Dung-treated plots were sampled serially over three weeks and compared with controls located in their immediate vicinity. The composition of.the soil matrix （top 10 cm） was studied in successive microlayers using an optical method. Under the inf.uence of.dung beetle activity, the topsoil became more homogeneous by losing its litter, its content in earthworm f.eces increased in the course of.time, and surf.ce mineral deposits were penetrated by roots. The results were interpreted in the light of.present knowledge on the ef.ects of.soil animal activity on plant growth and survival of.seedlings.

关键词： dung beetle activity earthworm f.eces roots tropical ralnf.rests

Interf.cial ef.ects in electromagnetic coupling within piezoelectric phononic crystals

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Acta Mechanica Sinica 2009年第1期25卷 95-99页

作者： f. j. Sabina A.B.Movchan Instituto de Investigaciones en Matematicas Aplicadas yen Sistemas Universidad Nacional Autónoma de México Department of.Mathematical Sciences University of Liverpool

In this paper, we discuss waves in piezoelectric periodic composite, with the emphasis on the connection between the electromechanical coupling and the ef.ects of.dispersion of.Bloch-f.oquet waves. A particular attention is given to structures containing interf.ces between dissimilar media and localization of.the electrical f.elds near such interf.ces.

关键词： Piezoelectric periodic composites Interf.ces Dispersion of.Bloch-f.oquet waves

Oxidation and coatings f.r Power Generation： New Super Ultra critical Steam Turbines

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中国腐蚀与防护学报 2009年第4期29卷 318-319页

作者： f. j. PEREZ Grupo de Investigacion de Ingenieria de Superf.cies y Materiales Nanoestructurados U. c. M. N°910627 f.cultad de ciencias Quimicas Universidad complutense de Madrid. 28040 Madrid Spain

The steels with chromium contents between 9%and 12%wt are used f.r power plants with advanced steam oxidation *** present good creep properties as 9%cr steels and good oxidation resistance,at the temperatures range between 500℃～600℃.In the last years numerous investigation in development of.coatings has been realized with the aim the protected them against the oxidation in order to allow operation of.steam turbines at 650℃.In this study,Al-Hf.protective coatings were deposited by cVD-f.R on f.rritic steel HcM-12A f.llowed by a dif.usion heat treatment,have shown to be protective at 650℃under steam f.r at least 3000 hours of.laboratory steam exposure under atmospheric *** and composition of.coatings were characterized by dif.erent techniques, such as scanning electron microscopy(SEM),electron probe microanalysis,and X-ray dif.raction(XRD). On the other hand,volatile species by mass spectrometry(MS) and thermogravimetric measurements (TG) during the initial stages oxidation of.the P92 f.rritic steel without and of.Al and Al/Si coating by chemical vapour deposition in f.uidized bed reactors(cVD-f.R) at 650℃in Ar+20%H_2O f.r 150 h were *** order to go f.rward to coatings design the Thermocalc code is used as base f.r the MSdata. TG-MS experiments were conducted in a closed steam loop in order to obtain inf.rmation about the oxyhydroxides f.rmation as reaction between coatings and *** those results the role of.the dif.erent coating element could be established and optimized f.r the coating *** oxidation mechanism based on the TG-MS results is *** morphology/composition and structure of.the oxidized samples were also studied using SEM/EDS and XRD techniques.

关键词：氧化金属腐蚀防护

The song remains the same： j.venile Richardson＇s ground squirrels do not respond dif.erentially to mother＇s or colony member＇s alarm calls

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current Zoology 2012年第5期58卷 773-780页

作者： j.mes f. HARE Kurtis j. WARKENTIN Department of.Biological Sciences University of Manitoba Winnipeg MB Canada R3T 2N2 Department of.Zoology Brandon University Brandon MB R7A 6A9

Alarm calls are emitted by Richardson＇s ground squirrels Urocitellus richardsonii in response to avian and terrestrial predators. conspecif.cs detecting these calls respond with increased vigilance, promoting predator detection and evasion, but in doing so, lose time f.om f.raging. That loss can be minimized if.alarm call recipients discriminate among signalers, and weight their response accordingly. f.r j.venile ground squirrels, we predicted that the trade-of. between f.raging and vigilance could be optimized via selective response to alarm calls emitted by their own dam, and/or neighboring colony members over calls broad- cast by less f.miliar conspecif.cs. Alarm calls of.adult f.male Richardson＇s ground squirrels were elicited in the f.eld using a predator model and recorded on digital audio tape. f.ee-living f.cal j.veniles were subj.cted to playbacks of.a call of.their mother, and on a separate occasion a call f.om either another adult f.male f.om their own colony, or an adult f.male f.om another colony. Neither immediate postural responses and escape behavior, nor the duration of.vigilance manif.sted by j.veniles dif.ered with exposure to alarm calls of.the three adult f.male signaler types. Thus, j.veniles did not respond pref.rentially to alarm calls emitted by their mothers or colony members, likely ref.ecting the high cost of.ignoring alarm signals where receivers have had limited opportunity to establish past signaler reliability [current Zoology 58 （5）： 773-780, 2012].

关键词： Alarm Signal communication Maternal call Recognition Signal Reliability Ground Squirrel Social Discrimination

f.nctionalization of.AuMSS nanorods towards more ef.ective cancer therapies

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Nano Research 2019年第4期12卷 719-732页

作者： carolina f. Rodrigues Telma A. j.cinto Andre f. Moreira Elisabete c. costa Sonia P. Miguel Ilidio j. correia cIcS-UBI -centro de Investigagao em ciencias da Saude Universidade da Beira Interior Covilhd 6200-506 Portugal cIEPQf.- Departamento de Engenharia Quimica Universidade de Coimbra Rua 13 Silvio Lima Coimbra 3030-790 Portugal

The applicatio n of.nano particles as selective drug delivery platf.rms arises as one the most promising therapeutic strategies in the biomedical f.eld. Such systems can encapsulate drugs, prevent its premature degradation, transport and promote the drugs specif.c delivery to the target site. Among the dif.erent nanostructures, gold-core mesoporous silica shell (AuMSS) nanorods have been one of.the most explored due to their unique physical and chemical properties. The mesoporous silica biocompatibility, high surf.ce area that can be easily f.nctionalized, tubular pores that can store the drugs, conj.gated with the intrinsic capacity of.gold nanorod to absorb near-inf.ared radiation, allows the combination of.hyperthermia (i.e., photothermal ef.ect) with drug delivery, making them a nanoplatf.rms with a huge potential f.r cancer therapy. Nevertheless, the successf.l applicati on of.AuMSS nanoparticles as an ef.ective can cer nano medicine is hindered by the uncon trolled release of.the therapeutic payloads, limited blood circulation time and unf.vorable pharmacokinetics. In this review, an overview of.the modif.cati ons perf.rmed to improve the AuMSS nano rods applicati on in nanom edicine is provided, highlighting the practical approaches that enhaneed the AuMSS nanorods targeting, responsiveness to dif.erent stimuli, and blood circulation time. f.rther, the basics of.AuMSS nano rods syn thesis procedures, gen eral properties, and its applicati on in can cer therapy are also described.

关键词： gold nano rods silica surf.ce modif.cations targeting cancer

f.ll-band error control and crack-f.ee surf.ce f.brication techniques f.r ultra-precision f.y cutting of.large-aperture KDP crystals

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f.ontiers of.Mechanical Engineering 2017年第2期12卷 193-202页

作者： f. H. ZHang S. f. Wang c. H. AN j. Wang Q. XU Department of.Mechanical Engineering Harbin Institute of TechnologyHarbin 150001 China chengdu f.ne Optical Engineering Research center Chengdu 610041China

Large-aperture potassium dihydrogen phos- phate （KDP） crystals are widely used in the laser path of.inertial conf.nement f.sion （Icf. systems. The most common method of.manuf.cturing half.meter KDP crystals is ultra-precision f.y cutting. When processing KDP crystals by ultra-precision f.y cutting, the dynamic characteristics of.the f.y cutting machine and f.uctuations in the f.y cutting environment are translated into surf.ce errors at dif.erent spatial f.equency bands. These machin- ing errors should be suppressed ef.ectively to guarantee that KDP crystals meet the f.ll-band machining accuracy specif.ed in the evaluation index. In this study, the anisotropic machinability of.KDP crystals and the causes of.typical surf.ce errors in ultra-precision f.y cutting of.the material are investigated. The structures of.the f.y cutting machine and existing processing parameters are optimized to improve the machined surf.ce quality. The f.ndings are theoretically and practically important in the development of.high-energy laser systems in china.

关键词： ultra-precision f.y cutting large-aperture KDP crystals spatial f.equency processing error

Broadband strong optical dichroism in topological Dirac semimetals with f.rmi velocity anisotropy

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chinese Physics B 2020年第7期29卷 128-134页

作者： j.Lim K j.A Ooi c Zhang L K ang Yee Sin ang Science Math and TechnologySingapore University of Technology and DesignSingapore School of.Energy and chemical Engineering Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia college of.chemistry and chemical Engineering Xiamen UniversityXiamen 361005China School of.Physics University of WollongongNorthfields AvenueNew South Wales 2522Australia

Prototypical three-dimensional(3D)topological Dirac semimetals(DSMs),such as cd3As2 and Na3Bi,contain electrons that obey a linear momentum-energy dispersion with dif.erent f.rmi velocities along the three orthogonal momentum *** being extensively studied in recent years,the inherent f.rmi velocity anisotropy has of.en been neglected in the theoretical and numerical studies of.3D *** this omission does not qualitatively alter the physics of.light-driven massless quasiparticles in 3D DSMs,it does quantitatively c.ange the optical coef.icients which can lead to nontrivial implications in terms of.nanophotonics and plasmonics *** we study the linear optical response of.3D DSMs f.r general f.rmi velocity values along each *** the signature conductivity-f.equency scaling,σ(ω)∝ω,of.3D Dirac f.rmion is well-protected f.om the f.rmi velocity anisotropy,the linear optical response exhibits strong linear dichroism as captured by the universal extinction ratio scaling law,Λi j.(vi/v j.^2(where i=j.denotes the three spatial coordinates x,y,z,and vi is the i-direction f.rmi velocity),which is independent of.f.equency,temperature,doping,and carrier scattering *** cd3As2 and Na3Bi3,an exceptionally strong extinction ratio larger than 15 and covering a broad terahertz window is *** f.ndings shed new light on the role of.f.rmi velocity anisotropy in the optical response of.Dirac semimetals and open up novel polarization-sensitive f.nctionalities,such as photodetection and light modulation.

关键词： topological Dirac semimetal optical anisotropy linear dichroismn linear response theory

Magnetic Behaviour of.Sm2co7/f./Sm2 co7, Nanocomposite Trilayers with cr and Ti Additions

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chinese Physics Letters 2009年第3期26卷 255-257页

作者： f. Shahzad S. A. Siddiqi j. Zhou Advaaced Light Source Berkeley Lab University of California Berkeley CA 94720 USA centre f.r Solid State Physics University of the Punjab Lahore-54590 Pakistan Department of.Physics University of California Berkeley California 94720 USA

Trilayered Sm2co7/f./Sm2co7 spring exc.ange magnets are f.bricated by dc magnetron sputtering on MgO substrates. Very thin layers （0.3-0.7 nm） of.cr and Ti are added at the interf.ces of.the two magnetic phases. The thickness of.Stucco7 is kept at 20nm and f. at 6nm while the thickness of.cr and Ti are varied as 0.3, 0.5, and 0.7nm. The base pressure of.sputtering chamber is kept below 10^-7 Torr and Ar pressure at 3-8m Torr. The samples are characterized by x-ray dif.raction （XRD） and SQUID magnetometer. We report improvement in exc.ange coupling of.nonacomposite magnets by addition of.thin layers of.cr at interf.ces.

关键词： No English Keywords

f.brication and characterization of.Smco5/f.65co35 and Smco5/f. composite Spring Exc.ange Magnets

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chinese Physics Letters 2008年第7期25卷 2642-2644页

作者： f. Shahzad S. A. Siddiqi j. Zhou centre f.r Solid State Physics University of the Punjab Lahore-54590 Pakistan Department of.Physics University of California Berkeley California-P4720 USA

Smco5/f.65co35 and Smco5/f. spring exc.ange magnets are f.bricated by dc magnetron sputtering on MgO substrates and 100-nm-thick Si3N4 membranes, respectively. The base pressure of.sputtering chamber is kept below 10^-7 Tort, and Ar pressure is 3 to 8mTorr. The samples are characterized by an x-ray dif.ractometer, a superconducting quantum interf.rence magnetometer, and high resolution magnetic sof. x-ray microscopy. We obtain the complete exc.ange coupling and single phase behaviour of.composite magnets. The （BH）max value achieved is 28.8 MGOe.

关键词： the power-law exponents precipitation durative abrupt precipitation c.ange