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Phylogeny,genetics,and the partial life cycle of Oncomegas wageneri in the Gulf of Mexico

current Zoology 2020年第3期66卷 275-283页

作者： Andrés MARTINEZ-AQUINO Víctor M.VIDAL-MARTINEZ f.sara c.c.arelli Oscar MENDEZ Lilia c.SOLER-JIMENEZ M.Leopoldina AGUIRRE-MAcEDO facultad de ciencias Universidad Autonoma de Baja CaliforniaCarretera Transpeninsular 3917Fraccionamiento PlayitasEnsenadaBaja California 22860Mexico Laboratorio de Patologia Acuatica Departamento de Recursos del MarCentro de Investigacion y de Estudios Avanzados del Instituto Politecnico NacionalUnidad MeridaCordemexCarretera Antigua a Progreso Km.6MeridaYucatan 97310Mexico Departamento de Biologia de la conservacion CONACYT-Centro de Investigacion Cientifica y de Educacion Superior de EnsenadaCarretera Ensenada-TjuanaEnsenadaBaja California 22860Mexico Laboratorio de Hidrobiologia Facultad de Biologia-XalapaUniversidad VeracruzanaCircuito Gonzalo Aguirre Beltran S/N Zona UniversitariaXalapaVeracruz 91090Mexico

Despite the diversity and ecological importance of cestodes,there is a paucity of studies on their life stages(i.e.,complete lists of intermediate,paratenic,and definitive hosts)and genetic *** example,in the Gulf of Mexico(GoM)98 species of cestodes have been reported to date;however,data on their intraspecific genetic variation and population genetic studies are *** trypanorhynch cestode,Oncomegas wageneri,is found(among other places)off the American Western Atlantic coast,including the GoM,and has been reported as an adult from stingrays and from several teleost species in its larval form(as plerocerci).This study represents the first report of 2 previously unregistered definitive hosts for ***,namely the Atlantic sharpnose shark Rhizoprionodon terraenovae and the southern stingray Hypanus *** this work,partial sequences of the 28S(region D1-D2)ribosomal DNA were analyzed to include *** within an eutetrarhynchoid phylogenetic *** *** individuals(which included plerocerci and adults)were recovered as monophyletic and Oncomegas celatus was identified as the sister species of ***,population genetic analyses of *** from the southern GoM were carried out using DNA sequences of the mitochondrial cytochrome c oxi-dase subunit 1(cOI)gene,which reflected high genetic variation and a lack of genetic structure among the 9 oceanographic sampling *** on these results,*** is panmictic in the southern *** extensive sampling along the species entire distribution is necessary to make more accurate inferences of population genetics of ***.

关键词： barcode cyclopsetta chittendeni population genetics Hypanus americanus Oncomegas Rhizoprionodon terraeno-vae 28S rDNA(D1-D2)

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THERMODYNAMIc VARIATIONAL APPROAcH fOR cLIMB Of AN EDGE DISLOcATION

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Acta Mechanica Solida Sinica 2009年第5期22卷 426-435页

作者： A.c.f.cocks Department of Engineering Science University of OxfordParks RoadOxfordOX1 3PJUK

A general thermodynamic variational approach is applied to study the force on an edge dislocation, which drives the dislocation to climb. Our attention is focused on the physical mechanism responsible for dislocation climb. A dislocation in a material element climbs as a result of vacancies diffusing into or out from the dislocation core, with the dislocation acting as a source or a sink for vacancy diffusion in the material element. The basic governing equations for dislocation climb and the climb forces on the dislocation are obtained naturally as a result of the present thermodynamic variational approach.

关键词： dislocation climb driving forces variational principle

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High Strain Rate Superplasticity in a Micro-grained Al-Mg-Sc Alloy with Predominant High Angle Grain Boundaries

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Journal of Materials Science & Technology 2012年第11期28卷 1025-1030页

作者： f. c. Liu Z.Y. Ma f. c. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004China

friction stir processing （fSP） was applied to extruded AI-Mg-Sc alloy to produce fine-grained microstructure with a grain size of 2.2μm. Electron backscatter diffraction （EBSD） result showed that the grain boundary misorientation distribution was very close to a random grain assembly for randomly oriented cubes. Super- plastic investigations in the temperature range of 425-500 ℃ and strain rate range of 1x100^-2-1x10 s^-1 showed that a maximum elongation of 1500% was achieved at 475 ℃ and a high strain rate of 1x100^-2-1x10 s^-1. The fSP AI-Mg-Sc exhibited enhanced superplastic deformation kinetics compared to that predicted by the constitutive relationship for superplasticity in fine-grained aluminum alloys. The origin for enhanced superplas- tic deformation kinetics in the fSP alloy can be attributed to its high fraction of high angle grain boundaries （HAGBs）. The analyses of the superplastic data and scanning electron microscopy （SEM） examinations on the surfaces of deformed specimens indicated that grain boundary sliding is the main superplastic deformation mechanism for the fSP AI-Mg-Sc alloy.

关键词： Superplasticity friction stir processing Aluminum Microstructure friction stir welding

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Engineering vibration monitoring by GPS:long duration records

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Earthquake Engineering and Engineering Vibration 2009年第3期8卷 459-467页

作者： f.casciati c.fuggini Department of Structural Mechanics University of PaviaItaly

Monitoring the performance of any structure requires real-time measurements of the change of position of critical points. Different techniques can be used for this purpose, each one offering advantages and disadvantages. The technique based on satellite positioning systems （GPS, GLONASS and the future GALILEO） seems to be very promising at least for long period structures. The GPS in particular provides sampling rates that are able to track dynamic displacements with high accuracy. Its service ability is independent of atmospheric conditions, temperature variations and visibility of the monitored object. This paper investigates the reliability and accuracy of the measurements of dual frequency GPS receivers. A linear electromagnetic motor moves an object along a given direction. The changes of position are compared witb their estimates as recorded by a GPS receiver, whose antenna is located on the reference object. The comparison is based on sufficiently long records.

关键词： infrastructure monitoring global positioning system (GPS) delay positioning errors multi-path error signal geometric dilution of precision linear motor amplitudes power spectral densities

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Impact of coronary angioplasty in elderly patients with non-ST-segment elevation myocardial infarction

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Journal of Geriatric cardiology 2020年第8期17卷 449-454页

作者： fernando f.Goncalves José P.Guimaraes sara c.Borges Pedro S.Mateus José I.Moreira cardiology Department Centro Hospitalar de Trás-os-Montes e Alto DouroVila RealPortugal

Background As treatment of coronary artery disease improved over the last years,management of elder patients remained a matter of debate since this age group has been underrepresented in most *** study aimed to evaluate a population of patients with≥85 years old with non-ST-segment elevation myocardial infarction(NSTEMI)and compare the prognosis according to coronary revascularization *** We retrospectively studied 324 patients included in a national multicenter registry between October 2010 and October 2018,who underwent coronary angiography and had at least one stenosis≥50%.Results In this population,73.1%of the patients underwent percutaneous coronary intervention(PcI)and 26.9%of the patients underwent optimized medical treatment(OMT).The OMT group had more past history of diabetes,stroke and *** coronary angiography,the PcI group used more often the femoral artery access and single-vessel lesions were also more ***-vessel disease was more common in the OMT *** hospitalization,there were more major bleeding events and death in the PcI *** the one-year follow-up,there were no significant differences in all-cause mortality *** Very old patients with NSTEMI submitted to OMT had more comorbidities and more three-vessel disease,factors that could have influenced the therapeutic *** undergoing PcI had more in-hospital major bleeding events and mortality,with no significant differences after one year.

关键词： coronary artery disease Revascularization The elderly

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Exact Time-Dependent Wave functions of a confined Time-Dependent Harmonic Oscillator with Two Moving Boundaries

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communications in Theoretical Physics 2009年第11期52卷 820-824页

作者： c.f.Lo Institute of Theoretical Physics and Department of Physics The Chinese University of Hong Kong

By applying the standard analytical techniques of solving partial differential equations, we have obtained the exact solution in terms of the fourier sine series to the time-dependent Schrodinger equation describing a quantum one-dimensional harmonic oscillator of time-dependent frequency confined in an infinite square well with the two walls moving along some parametric trajectories. Based upon the orthonormal basis of quasi-stationary wave functions, the exact propagator of the system has also been analytically derived. Special eases like （i） a confined free particle, （ii） a confined time-independent harmonic oscillator, and （iii） an aging oscillator are examined, and the corresponding time- dependent wave functions are explicitly determined. Besides, the approach has been extended to solve the case of a confined generalized time-dependent harmonic oscillator for some parametric moving boundaries as well.

关键词： infinite square well harmonic oscillator moving boundaries fourier series

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The Kirkendall effect on erosion resistance of chrome-coated 25cr3Mo2WNiV and 30SiMn2MoV gun barrel steels

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Journal of Materials Science & Technology 2024年第10期177卷 246-255页

作者： c.H.Dou P.f.Jin c.Z.Wang J.J.Li c.Zhang J.f.Huang c.Zhang Key Laboratory for Advanced Materials Processing State State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China National Joint Engineering Research center for Abrasion control and Molding of Metal Materials School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang 471003China

This study aimed to investigate the erosion behavior and mechanism of a newly developed 25cr3Mo2WNiV steel with a chrome coating using promoted ignition combustion *** erosion threshold pressure and temperature of the chrome-coated 25cr3Mo2WNiV steel were determined to be 0.2 MPa and 254.3 K higher than those of traditional chrome-coated 30SiMn2MoV ***,Kirkendall voids and inter-diffusion between the cr coating and matrix were first observed before *** improved erosion resistance of the chrome-coated 25cr3Mo2WNiV steel was attributed to the suppression of the Kirkendall effect,which minimized heat generation at the cr/matrix interface by pre-venting oxygen diffusion and reducing oxygen affinity.

关键词： Erosion resistance Kirkendall effect cr coating Gun steel

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A comparative study on emergent pollutants photo-assisted degradation using ruthenium modified titanate nanotubes and nanowires as catalysts

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Journal of Environmental Sciences 2020年第6期32卷 38-51页

作者： Beatriz Barrocas M.conceicao Oliveira Helena I.S.Nogueira sara fateixa Olinda c.Monteiro centro de Química Estrutural Faculdade de CienciasUniversidade de LisboaLisboa 1749-016Portugal centro Química Estrutural Instituto Superior TécnicoUniversidade de LisboaLisboa 1049-001Portugal Department of chemistry CICECO-Aveiro Institute of MaterialsUniversity of AveiroAveiro 3810-193Portugal

Several methods have been used to tailor nanomaterials structure and ***,slight changes in the structure outcomes expressive improvements in the optical and photocatalytic properties of semiconductor *** this context,the influence of the metal doping and the morphology on a catalyst performance was studied in this ***,ruthenium doped titanate nanotubes(RuTNT)were synthesised for the first time using an amorphous Ru-containing ***,the photocatalytic performance of this sample was compared to the one obtained for ruthenium titanate nanowires(RuTNW),recently *** samples,RuTNW and RuTNT,were produced using the same Ru-containing precursor but distinct hydrothermal *** powders were structural,morphological and optical characterized by X-ray diffraction and fluorescence,transmission electron microscopy,Raman,X-ray photoelectron and photoluminescence *** variations on the structural and optical properties of the RuTNT and RuTNW nanoparticles,due to ruthenium incorporation were *** potential use as photocatalysts was evaluated on the hydroxyl radical photo-assisted *** samples were catalytic for this reaction,presenting better performances than the pristine counterparts,being RuTNT the best ***,the degradation of two emergent pollutants,caffeine and sulfamethazine,was *** demonstrated to be better photocatalyst than RuTNW for caffeine but identical performances were obtained for *** both catalysts,the degradation mechanism of the pollutants was explored through the identification and quantification of the intermediate compounds produced and several differences were *** indicates the importance of the structural and morphological aspects of a material on its catalytic performance.

关键词： Titanate nanotubes and nanowires Ruthenium doping Ru-Ti replacement Emergent pollutants Photocatalytic degradation

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Hot cracking in AZ31 and AZ61 Magnesium Alloy

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Journal of Materials Science & Technology 2011年第7期27卷 633-640页

作者： c.J. Huang c.M. cheng c.P. chou f.H. chen Department of Mechanical Engineering National Chiao Tung University Hsinchu 300 Taiwan China Department of Industrial Education National Taiwan Normal University Taipei 106 Taiwan China

This paper examined the impact of the number of thermal cycles and augmented strain on hot cracking in AZ31 and AZ61 magnesium alloy. Statistical analyses were performed. following observation using a scanning electron microscope （SEM）, an energy dispersive spectrometer （EDS） was used for component analysis. Results showed that Al content in magnesium alloy has an effect on hot cracking susceptibility. In addition, the nonequilibrium solidification process produced segregation in Al content, causing higher liquid Mg-alloy rich Al content at grain boundaries, and resulting into liquefied grain boundaries of partially melted zone （PMZ）. In summary, under multiple thermal cycles AZ61 produced serious liquation cracking. AZ61 has higher （6 wt%） Al content and produced much liquefied Mg17Al12 at grain boundaries under multiple thermal cycles. The liquefied Mg17Al12 were pulled apart and hot cracks formed at weld metal HAZ due to the augmented strain. Since AZ31 had half the Al content of AZ61, its hot-cracking susceptibility was lower than AZ61. In addition, AZ61 showed longer total crack length （TcL） in one thermal cycle compared to that in three thermal cycles. This phenomenon was possibly due to high-temperature gasification of Al during the welding process, which resulted in lower overall Al content. consequently, shorter hot cracks exhibited in three thermal cycles. It was found the Al content of AZ31 and AZ61 can be used to assess the hot-cracking susceptibility.

关键词： Varestraint test Thermal cycles Hot-cracking susceptibility Gas tungsten arc welding (GTAW) AZ31 AZ61

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Biofuel-driven trigeneration systems for non-residential building applications:A holistic assessment from the energy,environmental and economic perspectives

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Building Simulation 2023年第4期16卷 557-576页

作者： K.f.fong c.K.Lee Division of Building Science and Technology College of EngineeringCity University of Hong KongTat Chee AvenueKowloonHong KongChina

In the metropolises,it is unlikely to use merely solar and wind energy to pursue zero carbon building ***,it would become possible if biofuel-driven trigeneration systems(BDTS)are *** is thus essential to assess the application opportunity of BDTS in a holistic *** this study,BDTS offered definite primary energy saving of up to 15%and carbon emissions reduction of at least 86%in different types of non-residential buildings as compared to the conventional *** 24/7 operation for the hotel and hospital buildings,the corresponding BDTS could even achieve zero carbon *** the BDTS primed with compression-ignition internal combustion engine were not economically viable even in running cost due to the high local biodiesel price *** BDTS primed with spark-ignition engine and fueled by biogas,however,would have economic merit when carbon price was considered for the conventional systems that fully utilize fossil *** of carbon tax and social cost could have the payback ceilings of 8 years and 2 years respectively for most of building ***,the results could reflect the application potential of BDTS for non-residential buildings,leading the pathway to carbon neutrality for sustainable sub-tropical cities.

关键词： trigeneration biofuel dynamic simulation carbon tax social cost economic analysis

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