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A review on the application of modified continuum models in modeling and simulation of nanostructures

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Acta Mechanica Sinica 2016年第1期32卷 83-100页

作者： K.F.Wang B.l.Wang t.Kitamura Graduate School at Shenzhen Harbin Institute of Technology Department of Mechanical Engineering Kyoto University

Analysis of the mechanical behavior of nanos- tructures has been very challenging. Surface energy and non- local elasticity of materials have been incorporated into the traditional continuum analysis to create modified continuum mechanics models. this paper reviews recent advancements in the applications of such modified continuum models in nanostructures such as nanotubes, nanowires, nanobeams, graphenes, and nanoplates. A variety of models for these nanostructures under static and dynamic loadings are men- tioned and reviewed. Applications of surface energy and nonlocal elasticity in analysis of piezoelectric nanomateri- als are also mentioned. this paper provides a comprehensive introduction of the development of this area and inspires fur- ther applications of modified continuum models in modeling nanomaterials and nanostructures.

关键词： Surface elasticity Nonlocal continuum Nanotubes Nanobeams Nanoplates Modeling andsimulations

EXAFS study of cation reordering in NaYF_4:Yb^(3+),tb^(3+) up-conversion luminescence materials

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Journal of Rare Earths 2014年第3期32卷 226-229页

作者： H.F.Brito J.Hls t.laamanen t.laihinen M.lastusaari l.Pihlgren l.C.V.Rodrigues t.Soukka Instituto de Química Universidade de S?o Paulo Department of Chemistry University of Turku turku University Centre for Materials and Surfaces (MatSurf) Department of Chemistry University of Turku FI-20014 Turku Finland turku University Centre for Materials and Surfaces (MatSurf) Turku Finland University of turku Graduate School (UtUGS) Doctoral Programme in Physical and Chemical Sciences Graduate School of Materials Research (GSMR) Department of Biochemistry University of Turku

the NaYF4：yb3＋,tb3＋（Xyb： 0.20, Xtb： 0.04） materials were prepared using the co-precipitation method, lne as-preparea material was washed either with or without water in addition to ethanol and thereafter annealed for 5 h at 500℃. this resulted in materials with moderate or very high up-conversion luminescence intensity, respectively. the structural study carried out with X-ray powder diffraction revealed microstrains in the rare earth （R） sublattice that were relaxed for the material with very high up-conversion intensity thus decreasing energy losses. the local structural details were investigated with R lⅢ and Y K edge ex- tended X-ray absorption fine structure （EXAFS） using synchrotron radiation. Around 10 tool.% of the Yb3＋ ions were found to occupy the Na site in the material with very high up-conversion intensity. these Yb species formed clusters with the tb3＋ ions occupying the regular Na/R sites. Such clustering enhanced the energy transfer between Yb3＋ and tb3＋ thus intensifying the up-conversion emission.

关键词： EXAFS up-conversion ytterbium terbium cation reordering

Projecting future precipitation change across the semi-arid Borana lowland,southern Ethiopia

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Journal of Arid land 2023年第9期15卷 1023-1036页

作者： Mitiku A WORKU Gudina l FEYISA Kassahun t BEKEtIE Emmanuel GARBOlINO Department of Environment and Climate Change Management Ethiopian Civil Service UniversityAddis Ababa 1000Ethiopia Center for Environmental Science Addis Ababa UniversityAddis Ababa 1000Ethiopia Climpact Data Science Nova-Sophia 06904France

Climate change caused by past,current,and future greenhouse gas emissions has become a major concern for scientists in the field in many countries and regions of the *** study modelled future precipitation change by downscaling a set of large-scale climate predictor variables(predictors)from the second generation Canadian Earth System Model(CanESM2)under two Representative Concentration Pathway(RCP)emission scenarios(RCP4.5 and RCP8.5)in the semi-arid Borana lowland,southern *** Statistical DownScaling Model(SDSM)4.2.9 was employed to downscale and project future precipitation change in the middle(2036-2065;2050s)and far(2066-2095;2080s)future at the local *** precipitation observations from eight meteorological stations stretching from 1981 to 1995 and 1996 to 2005 were used for the model calibration and validation,respectively,and the time period of 1981-2018 was considered and used as the baseline period to analyze future precipitation *** results revealed that the surface-specific humidity and the geopotential height at 500 hPa were the preferred large-scale *** to the middle future(2050s),precipitation showed a much greater increase in the far future(2080s)under both RCP4.5 and RCP8.5 scenarios at all meteorological stations(except teletele and Dillo stations).At teltele station,the projected annual precipitation will decrease by 26.53%(2050s)and 39.45%(2080s)under RCP4.5 scenario,and 34.99%(2050s)and 60.62%(2080s)under RCP8.5 ***,the main rainy period would shift from spring(March to May)to autumn(September to November)at Dehas,Dire,Moyale,and teltele stations,but for Arero and Yabelo stations,spring would consistently receive more precipitation than *** can be concluded that future precipitation in the semi-arid Borana lowland is predicted to differ under the two climate scenarios(RCP4.5 and RCP8.5),showing an increasing trend at most meteorological *** information could be he

关键词： future precipitation climate change second generation Canadian Earth System Model(CanESM2) Statistical DownScaling Model(SDSM) semi-arid Borana lowland southern Ethiopia

A review of whole-medical systems and holistic care approach for type 2 diabetes and associated metabolic syndrome

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Journal of Integrative Medicine 2024年第3期22卷 199-209页

作者： loveness Makoni Idah t.Manduna Alaisa l.Mbiriri Department of Health Sciences Faculty of Health and Environmental Health SciencesCentral University of TechnologyFree State20 President Brand StreetPrivate bag X20539Bloemfontein 9300South Africa Centre for Applied Food Sustainability and Biotechnology(CAFSaB) Faculty of Health and Environmental Health SciencesCentral University of TechnologyFree State20 President Brand StreetPrivate bag X20539Bloemfontein 9300South Africa Adventist Development and Relief Agency(ADRA) 5 Cecil RoadGreendaleHarare 0000Zimbabwe

Whole-person care and holistic care approach has been proposed for complementary and integrative health care for type 2 diabetes ***,some doubts still exist on the feasibility of replicating processes followed in clinical trials and observational studies in real-world *** narrative literature review summarized and assessed existing clinical evidence(clinical trials,observational studies,and case reports)describing holistic and integrated care approach in adult and adolescent individuals with type 2 diabetes mellitus in clinical *** goal was to highlight existing evidence for implementation and outcomes of whole-medical systems and holistic integrated care approach for type 2 diabetes mellitus.A nonsystematic literature search was performed on Google Scholar,PubMed,Web of Science,ProQuest and ScienceDirect to identify clinical evidence from different parts of the world,evaluating the use of whole-medical systems and/or holistic care interventions in clinical practice for management of type 2 diabetes *** keywords were used in the *** were analyzed using content analysis and simple descriptive statistics(percentages).Most of the studies(64%)were mainly conducted in Eastern countries(India,China and Israel)while 36%of the studies were conducted in the Western countries(USA,Netherlands,Canada and Mexico).lifestyle medicine and integrated naturopathy were shown to be the commonly used whole-medical systems for type 2 diabetes mellitus *** improvements in type 2 diabetes parameters,medication use,other symptoms,and overall feeling of wellness were observed in all *** review study revealed limited utilization and/or documentation of whole-medical systems or holistic care treatments for type 2 diabetes mellitus in regions of the world other than eastern *** medicine,naturopathy,yoga,Ayurveda and traditional Chinese medicine were shown to be effective for type 2 diabetes mellitu

关键词： Complementary and alternative medicine Holistic care Integrative medicine type 2 diabetes mellitus team-based intervention

INDOOR AIR QUAlItY IN ENERGY EFFICIENt HOUSING

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Journal of Green Building 2006年第2期1卷 32-38页

作者： t.l.thatcher Department of Civil and Environmental Engineering California Polytechnic State UniversitySan Luis ObispoCA 93407

INtRODUCtION Over the past decade,there has been an increasing effort to reduce leakage and air infiltration in new residential construction in order to improve energy *** example,California’s title 24 Residential Compliance Manual For California’s 2005 Energy Efficiency Standards,which went into effect in October 2005,recognizes that air infiltration(leakage)is a“major component of heating and cooling loads,”and section 3 addresses measures to reduce infiltration,such as sealing around penetrations,installing air-retarding wrap,and meeting window performance *** reducing infiltration has a positive effect on energy efficiency,a lack of adequate ventilation can lead to poor indoor air *** residences need to balance the desire for energy conservation with the need for high quality indoor *** this requires an understanding of the factors which affect air quality in homes.

关键词： install sealing leakage

Asymptotics for filtration of polydisperse suspension with small impurities

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Applied Mathematics and Mechanics(English Edition) 2021年第1期42卷 109-126页

作者： l.I.KUZMINA Y.V.OSIPOV t.N.GORBUNOVA Department of Applied Mathematics National Research University Higher School of EconomicsMoscow 101000Russia Department of Applied Mathematics Moscow State University of Civil Engineering(National Research University)Moscow 129337Russia

A model for deep bed filtration of a polydisperse suspension with small impurities in a porous medium is *** suspended particles move with the same velocity as the carrier water and get blocked in the pore throats due to the size-exclusion mechanism of particle retention.A solution of the model in the form of a traveling wave is *** global exact solution for a multiparticle filtration with one high concentration and several low concentrations of suspended particles is obtained in an explicit *** analytic solutions for a bidisperse suspension with large and small particles are *** profiles of the retained small particles change monotony with *** global asymptotics for the filtration of a polydisperse suspension with small kinetic rates is constructed in the whole filtration zone.

关键词： deep bed filtration suspension colloid porous medium particle size distribution analytical model

Cr（V）involvementin the toxicity pathway of testicular damage

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Asian Journal of Andrology 2002年第2期4卷 153-155页

作者： M.l.Pereira t.M.Santos 等 DepartmentofBiology Departmentofchemistry UniversityofAveriro3810－193AveiroPortugal

AIM:the functional integrity of the blood-testis barrier (BtB) in male mice exposed to Cr(V) was studied in order to clarify the mechanism underlying testicular injury.MEtHODS:Adult male mice were subcutaneously injected repeated doses of 8.02 micromol (0.5 ml) of Cr/*** for 5 days. Animals receiving a similar volume of bis(hydroxyethyl)-aminotris(hydroxymethyl)methane buffer (Bt) were used as controls. the animals were sacrificed on day 6 and small fragments of seminiferous tubules, approximately 8-10 mm length, were incised and sutured at both ends. they were exposed in vitro to horseradish peroxidase-containing culture medium for 10 minutes. tissues were then fixed and processed for ultrastructural studies.RESUltS:Controls and Cr(V)-treated group resulted in the uptake of the tracer by Sertoli cells. However, the major finding consisted in the permeability of the BtB only in the Cr(V)-group, as evidenced by the presence of the tracer within the junctions between the neighbouring Sertoli cells.CONClUSION:the BtB is disrupted in mice submitted to Cr(V). the permeability of the BtB is a crucial feature to be investigated for the understanding of lesions within the seminiferous tubule.

关键词： Blood-testis barrier Cr(V) Horseradish peroxidase Integrity Spermatogenesis

Effect of long-term thermal Exposure on Microstructure and Stress Rupture Properties of GH3535 Superalloy

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Journal of Materials Science & technology 2015年第3期31卷 269-279页

作者： t.liu J.S.Dong l.Wang Z.J.li X.t.Zhou l.H.lou J.Zhang School of Materials Science and Engineering Dalian University of Technology Institute of Metal Research Chinese Academy of Sciences Shanghai Institute of Applied Physics Chinese Academy of Sciences Shenyang National laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

the evolution of microstructure and the stress rupture properties of long term thermally exposed GH3535 alloy have been investigated. It was found that M6 C carbides presented in the solid solution heat treated samples. During long term thermal exposure at 700 C, fine M12 C carbides precipitated preferentially at grain boundaries. these carbides coexisted with the pre-exiting M6 C. the stress rupture life of700 C/1000 h exposed sample under creep testing at 650 C/324 MPa is 93 h. It is much longer than that of the solid solution samples. No noticeable changes could be detected in both the microstructure and stress rupture lives when the samples were exposed for time longer than 1000 h M12 C carbides were found to be beneficial to the creep properties. the cracks initiated at the interface of M6 C carbides and matrix, which led to a lower creep rupture life.

关键词： GH3535 superalloy long term thermal exposure Micro

An ultra-wideband circularly polarized microstrip patch antenna loaded with split-ring resonator

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Optoelectronics letters 2025年

作者： WANG Shike XIA Dan lü lianrong QIN Juan WANG Meng REN Haiping School of Integrated Circuit Science and Engineering， tianjin University of technology

In this paper， the effect of a single-opening split-ring resonator （SRR） structure on the performance of ultra-wideband （UWB） microstrip patch antenna （MPA） is studied. Here a UWB MPA based on partial grounding is proposed， and the SRR structure is utilized to optimize other characteristics of the low-profile microstrip antenna while ensuring the bandwidth and gain remain unchanged. the proposed metamaterial structure， consisting of a 2 × 2 array of SRR， is loaded on the reverse side of the substrate. the volume of the proposed antenna is 61.6×67.6×1.5mm3. According to simulation and experimental results， the proposed microstrip antenna loaded with 2×2 SRRs performs better than that without SRR structure. It produces an operating band of 1.62 GHz-8 GHz while achieving circular polarization characteristics with an axial ratio （AR） bandwidth of 3.92 GHz-4.57 GHz. In addition， the performance of the proposed antenna is superior to relevant works of literature the antenna can be widely utilized in wireless communication systems.

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