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Effects of Increasing Tungsten on Structural,Elastic and Optical Properties of xWO_3-(40-x)Ag_2O-60Te_2O Glass System

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Journal of Materials Science & Technology 2015年第1期31卷 83-90页

作者： MM.Umair A.K.Yahya M.K.halimah h.A.A.Sidek School of Physics and Materials Studies Universiti Teknologi MARA Department of Physics Faculty of ScienceUniversiti Putra Malaysia

Ternary teiiurite glasses with composition of xWO3（40-x）Ag2O-60TeO2（x=0-40 mol%） have been prepared by melt-quenching *** and optical properties of the glass system were obtained by ultrasonic velocity measurements and UV-vis spectroscopy,respectively,while structural investigation was carried out by using Raman *** longitudinal and shear velocities,vLand vsshowed large increase at x from 0 to 20 mol%before decrease with further addition of *** longitudinal modulus CLand shear modulus μ bulk modulus KeYoung’s modulus Vand Debye temperature θDshowed similar behaviors to both *** large increase of the elastic moduli at x from 0 to 20 mol%is suggested to be due to the increase in WO6octahedral unit structure indicating the increase of bridging oxygen（BO） and formation of stronger Te-O-W bonds compared to Te-O-Te *** the other hand,forx> 20 mol%,the decrease in the elastic moduli was due to the increase of non-bridging oxygen（NBO） as a result of formation of WO4tetrahedral via breaking Te-O-W *** analysis by using bulk compression and ring deformation models showed a slight decrease in the ratio of ideal bulk modulus Kbcto the experimental bulk modulus Keand average atomic ring size,/ for× 20 mol%.Our analysis also indicates that limited ring deformation took place and the main compression mechanism in this glass system was mainly ideal isotropic *** the other hand,optical band gap Eoptshowed small variation for x=0-20 mol%but decreased upon higher WO3content while refractive index n showed the opposite *** optical behavior is suggested to be related to the changes in cross link density and NBO concentration in the glass system.

关键词： Elastic moduli Optical absorption Raman spectrosco

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Lophozonia tree cavities used for nesting by Slender-billed Parakeets(Enicognathus leptorhynchus)in the central valley of southern Chile:a potentially vanishing keystone resource

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Chinese Birds 2017年第1期8卷 25-36页

作者： Thomas h.White Jr. Jaime E.Jiménez Puerto Rican Parrot Recovery Program United States Fish and Wildlife ServiceBox 1600Rio GrandePR 00745USA Sub-Antarctic Biocultural Conservation Program Department of Biological SciencesUniversity of North TexasDentonTX 76201USA Sub-Antarctic Biocultural Conservation Program Department of Philosophy and ReligionUniversity of North TexasDentonTX 76201USA Omora Etnobotanical Park Universidad de MagallanesPuerto WilliamsChile

Background: The Slender-billed Parakeet(Enicognathus leptorhynchus) is a psittacine endemic to southern Chile and an obligate secondary cavity-nester. In the central valley of southern Chile, most(94%) of the known Slender-billed Parakeet nests have occurred in large, mature southern beech(Lophozonia obliqua) trees(locally known as "pellines"). As relicts of the original old-growth forests of southern Chile, most pellines have been lost due to extensive landclearing throughout the region, potentially threatening long-term persistence of the Slender-billed ***: We conducted our study in the central valley of southern Chile, near the city of Osorno during three consecutive nesting seasons(November–January, 2008–2011). Nest trees used by Slender-billed Parakeets were located by direct observation of parakeet activities and through interviews with local residents, some of whom were former parrot nest poachers. Nest cavities were accessed, inspected and measured using single-rope climbing techniques. We report means, standard errors, 95% confidence intervals and ranges for 11 cavity-related variables. We also report clutch sizes encountered in active nests, and age estimates of nest trees based on known growth rates of Lophozonia trees in southern Chile. Linear regressions were used to evaluate potential relationships between cavity-related variables and clutch ***: We located and measured 38 Lophozonia tree cavities used for nesting by Slender-billed Parakeets. Compared to those used by other psittacines, nest trees were relatively large, averaging 30.4 breast height of 134.5 ter ± 1.1 m in height with a mean diameter at ± 4.7 cm. Based on estimated annual diameincrement, ages of nest trees ranged from approximately 209–485 years. Nest cavities entrances averaged 12.5 ± 0.9 m in height above ground level. Cavity entrance widths averaged 51.0 ± 13.3 cm(vertical) by 11.5 ± 0.7 cm(horizontal). Cavity entrance orientations were apparently random, with

关键词： Conservation Deforestation habitat loss Lophozonia obliqua Pellines Psittacidae Regeneration

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TURBULENT COhERENT STRUCTURES IN ChANNELS WITh SAND WAVES

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Journal of hydrodynamics 2001年第2期13卷 106-110页

作者： Liu, S.h. Coll. of Water Res. and hydropower Wuhan Univ. Wuhan 430072 China

Sand wave bed is one of the typical shape of complicated boundaries in hydraulics and river dynamics, and sand wave motion is the main form of the bed load motion in rivers, thence the study of turbulent structure over sand waves is of importance both in theory and practice. In this paper turbulent coherent structures over single-and multi-sand waves were studied experimentally, the formulae for the separation length and vortex shedding period of the turbulent flow over single-sand wave were suggested, and the characteristics of turbulent coherent structures over multi-sand waves were also given.

关键词： Sand Sediments Turbulence Two phase flow

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Petrogenesis of the ükapili Granitoid and its Mafic Enclaves in Elmal Area (Nigde, Central Anatolia, Turkey)

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 738-748页

作者： hüseyin KURT Kerim KOAK Kürsad ASAN Mustafa KARAKAS Department of Geological Engineering Seluk University Central Anatolia Directorate of Mineral Research and Exploration

The Late Cretaceous Uckapth Granitoid including mafic microgranular enclaves intruded into metapelitic and metabasic rocks, and overlain unconformably by Neogene ignimbrites in the Ni^de area of Turkey. It is mostly granite and minor granodiorite in composition, whereas its enclaves are dominantly gabbro with a few diorites in composition. The Uckapdl Granitoid is composed mainly of quartz, K-feldspar, plagioclase, biotite, muscovite and minor amphibole while its enclaves contain mostly plagioclase, amphibole, minor pyroxene and biotite. The Uckapth Granitoid has calcalkaline and peraluminous （AJCNK= 1.0-1.3） geochemical characteristics. It is characterized by high LILE/hFSE and LREE/hREE ratios （（La/Lu）N 3-33）, and has negative Ba, Ta, Nb and Eu anomalies, resembling those of comsion granitoids. The {）fkaplh Granitoid has relatively high STSr/S6Sr0） ratios （0.711189--0.716061） and low eNd（t） values （-5.13 to -7.13）, confirming crustal melting. In contrast, the enclaves are tholeiitic and metaluminous, and slightly enriched in LILEs （K, Rb） and Th, and have negative Ta, Nb and Ti anomalies; propose that they were derived from a subduction-modified mantle source. Based on mineral and whole rock chemistry data, the Uckapth granitoid is h-（hybrid） type, post-collision granitoid developed by mixing/mingllng processes between crustal melts and mantle-derived mafic magmas.

关键词： h-type granitoid mafic enclave geochemistry Central Anatolia Turkey

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Robust switched fractional controller for performance improvement of single phase active power filter under unbalanced conditions

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Frontiers in Energy 2016年第2期10卷 203-212页

作者： h. AFGhOUL F. KRIM D. ChIKOUChE A. BEDDAR LASS Laboratory Electronics Department Technology faculty University Mohamed Boudiaf of M'sila BP.166 Route Ichebilia M'sila28000 Algeria LEPCI Laboratory Electronics Department University of Ferhat AbbasSetif-1 route de B6jaia Setif 19000 Algeria Department of Electrical Engineering Technology faculty SkikdaUniversity Skikda 21000 Algeria

A novel controller is proposed to regulate the DC-link voltage of a single phase active power filter （SPAPF）. The proposed switched fractional controller （SFC） consists of a conventional PI controller, a fractional order PI （FO-PI） controller and a decision maker that switches between them. Commonly, the conventional PI controller is used in regulation loops due to its advantages in steady-state but it is limited in transient state. On the other hand, the FO-PI controller overcomes these draw- backs but it causes dramatic degradation in control performances in steady-state because of the fractional calculus theory and the approximation method used to implement this kind of controller. Thus, the purpose of this paper is to switch to the PI controller in steady-state to obtain the best power quality and to switch to the FO-PI controller when external disturbances are detected to guarantee a fast transient state. To investigate the efficiency and accuracy of the SFC considering all robustness tests, an experimental setup has been established. The results of the SFC fulfill the requirements, confirm its high performances in steady and transient states and demon- strate its feasibility and effectiveness. The experiment results have satisfied the limit specified by the IEEE harmonic standard 519.

关键词： conventional PI controller fractional calculus(FC) total harmonic distortion (ThD) Oustaloup contin-uous approximation (OCA) single phase active power filter(SPAPF)

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Noble gas isotopes in natural gases from Central and Northwest China

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Chinese Science Bulletin 1997年第10期42卷 838-841页

作者： Xu, S Xu, YC Shen, P Nakal, S Wakita, h State Key Laboratory of Gas Geochemistry Lanzhou Institute of Geology Lanzhou China Laboratory for Earthquake Chemistry Faculty of Science University of Tokyo China

As chemically inert elements,the variations of noble gas abundance and isotope during geologi-cal processes are not significantly affected by complex chemical process but mainly depend onthe control of physical processes such as solution,absorption,adsorption and nuclear ***,studies on noble gas geochemistry will play an important role in the geologi-cal processes such as genesis of natural *** this purpose,this study has measured 4 Ch4-rich natural gases in sedimentary basins from Central and Southwest China for all noble

关键词： natural gas noble gas isotope crustal component.

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CT Thresholds for Spinal Bone Mineral Attenuation to Prioritize Eligible Older Women for Osteoporosis Screening

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Open Journal of Radiology（放射学期刊） 2024年第2期 92页

作者： Seo Yeon K.Orite Bryn higuchi hyo-Chun Yoon Lana h.Gimber

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STRAIN RATE SENSITIVITY OF ULTRAFINE-GRAINED Cu WITh NANOSIZED TWINS

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Acta Metallurgica Sinica(English Letters) 2006年第5期19卷 313-318页

作者： L.X. Liu X.h. Chen L. Lu Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

An ultrafine-grained Cu sample with a high density of growth twins was synthesized by means of pulsed electrodeposition technique. The strain rate sensitivity of the Cu sample was measured by strain rate cycling tests under tension. The effects of grain size as well as twin density on the strength and strain rate sensitivity were discussed.

关键词： copper nanosized twin strain rate sensitivity deformation mechanism

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Challenges facing venous thromboembolism in China： more public awareness and research needed

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Chinese Medical Journal 2010年第4期123卷 387-389页

作者： WANG Chen ZhAI Zhen-guo Ying h Shen Beijing Institute of Respiratory Medicine Beijing Chaoyang Hospital Capital Medical University Beijing 100020 China Baylor College of Medicine Houston Texas USA

Venous thromboembolism （VTE）, composed of deep venous thrombosis （DVT） and pulmonarythromboembolism （PTE）, has been recognized as worldwide health problem not only in the western countries but also in Asian-Pacific regions. Tremendous progress has been made in recent years in identifying the potential risk factors, understanding the pathogenesis and developing therapeutic approaches for VTE. however, most of the currently available data are from American and European populations. Limited data from Chinese population are validated. Efforts should be made to increase public awareness, and promote clinical and translational research of VTE in modem China.

关键词： PULMONARY-EMBOLISM ThROMBOSIS

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Photochemistry of phenothiazine in benzene and cyclohexane

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Chinese Science Bulletin 1997年第12期42卷 998-1000页

作者： Wang, Sh Chen, DW Gou, JX Wang, h Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

IN the last few years phenothiazine(PTh)and its derivatives have captured much attention inthe fields of medicines,biology,and microelectronic materials due to their ability to ef-ficiently photosensitize acid production in the presence of vicinal dibromides and hence tochange the solubilization of polymer *** photophysical and photochemical properties re-lated to the processes have been *** Barra et *** that the triplet

关键词： photochemistry ESR nitroxyl radical cation radical.

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