Base de dados : MEDLINE
Pesquisa : G01.906.730 [Categoria DeCS]
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  1 / 1823 MEDLINE  
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[PMID]:29475281
[Au] Autor:Chen X; Gao J; Kang B
[Ti] Título:Achieving a tunable metasurface based on a structurally reconfigurable array using SMA.
[So] Source:Opt Express;26(4):4300-4308, 2018 Feb 19.
[Is] ISSN:1094-4087
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We introduce a structurally reconfigurable metasurface which is made of shape memory alloys (SMA). It could change the morphology of the unit cells repeatedly as we expect in response to a thermal stimulus and realize a tuning range from 13.3GHz to 17.2GHz for both polarizations simultaneously. Equivalent circuit models describe the operational principle and design methodology, the physical mechanism is interpreted with the variation of surface current distribution on the structure. The experimental results coincide with the numerical simulations, making the all-metal metasurface an attractive choice for manipulating the electromagnetic wave in a wide range of spectrums with the merits of higher controllability for dynamic behavior and greater freedom for design and manufacturing.
[Mh] Termos MeSH primário: Ligas/química
Campos Eletromagnéticos
Eletrônica/instrumentação
Óptica e Fotônica/instrumentação
[Mh] Termos MeSH secundário: Desenho de Equipamento
Modelos Teóricos
Condutividade Térmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alloys)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180302
[Lr] Data última revisão:
180302
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180225
[St] Status:MEDLINE
[do] DOI:10.1364/OE.26.004300


  2 / 1823 MEDLINE  
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[PMID]:29219437
[Au] Autor:Li QY; Takahashi K; Zhang X
[Ad] Endereço:Department of Aeronautics and Astronautics, Kyushu University, Fukuoka 819-0395, Japan.
[Ti] Título:Comment on "Divergent and Ultrahigh Thermal Conductivity in Millimeter-Long Nanotubes".
[So] Source:Phys Rev Lett;119(17):179601, 2017 10 27.
[Is] ISSN:1079-7114
[Cp] País de publicação:United States
[La] Idioma:eng
[Mh] Termos MeSH primário: Nanotubos de Carbono
Condutividade Térmica
[Mh] Termos MeSH secundário: Seres Humanos
[Pt] Tipo de publicação:LETTER; COMMENT
[Nm] Nome de substância:
0 (Nanotubes, Carbon)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180110
[Lr] Data última revisão:
180110
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171209
[St] Status:MEDLINE
[do] DOI:10.1103/PhysRevLett.119.179601


  3 / 1823 MEDLINE  
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[PMID]:28934220
[Au] Autor:Khan WS; Hamadneh NN; Khan WA
[Ad] Endereço:Department of Mechanical & Industrial Engineering, College of Engineering Majmaah University, Majmaah, Kingdom of Saudi Arabia.
[Ti] Título:Prediction of thermal conductivity of polyvinylpyrrolidone (PVP) electrospun nanocomposite fibers using artificial neural network and prey-predator algorithm.
[So] Source:PLoS One;12(9):e0183920, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In this study, multilayer perception neural network (MLPNN) was employed to predict thermal conductivity of PVP electrospun nanocomposite fibers with multiwalled carbon nanotubes (MWCNTs) and Nickel Zinc ferrites [(Ni0.6Zn0.4) Fe2O4]. This is the second attempt on the application of MLPNN with prey predator algorithm for the prediction of thermal conductivity of PVP electrospun nanocomposite fibers. The prey predator algorithm was used to train the neural networks to find the best models. The best models have the minimal of sum squared error between the experimental testing data and the corresponding models results. The minimal error was found to be 0.0028 for MWCNTs model and 0.00199 for Ni-Zn ferrites model. The predicted artificial neural networks (ANNs) responses were analyzed statistically using z-test, correlation coefficient, and the error functions for both inclusions. The predicted ANN responses for PVP electrospun nanocomposite fibers were compared with the experimental data and were found in good agreement.
[Mh] Termos MeSH primário: Eletricidade
Nanocompostos/química
Nanotecnologia
Redes Neurais (Computação)
Povidona/química
Condutividade Térmica
[Mh] Termos MeSH secundário: Compostos Férricos/química
Nanotubos de Carbono/química
Níquel/química
Zinco/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ferric Compounds); 0 (Nanotubes, Carbon); 0 (nickel ferrite); 7OV03QG267 (Nickel); FZ989GH94E (Povidone); J41CSQ7QDS (Zinc)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170922
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0183920


  4 / 1823 MEDLINE  
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[PMID]:28686643
[Au] Autor:Hayat T; Haider F; Muhammad T; Alsaedi A
[Ad] Endereço:Department of Mathematics, Quaid-I-Azam University, Islamabad, Pakistan.
[Ti] Título:Three-dimensional rotating flow of carbon nanotubes with Darcy-Forchheimer porous medium.
[So] Source:PLoS One;12(7):e0179576, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Here we are concerned with the Darcy-Forchheimer three-dimensional flow of carbon nanotubes in a rotating frame. Flow is generated by stretching of the surface. Xue model is adopted for nanofluid transport mechanism. Results for single wall carbon nanotubes (SWCNTs) and multi wall carbon nanotubes are achieved and compared. Flow saturating porous space obeys Darcy-Forchheimer expression. Boundary layer approximations are invoked to simplify governing partial differential system. Optimal homotopy analysis method (OHAM) is utilized for solutions of governing model. The optimal values of auxiliary parameters are computed. Plots have been displayed in order to analyze how the velocities and temperature fields get affected by various flow parameters. Skin-friction coefficients and local Nusselt number are presented through numerical data for both SWCNTs and MWCNTs. Moreover the skin-friction coefficients and local Nusselt number are enhanced for larger values of nanoparticles volume fraction.
[Mh] Termos MeSH primário: Modelos Químicos
Nanoestruturas/química
Nanotubos de Carbono/química
[Mh] Termos MeSH secundário: Algoritmos
Convecção
Nanopartículas
Porosidade
Propriedades de Superfície
Condutividade Térmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Nanotubes, Carbon)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171004
[Lr] Data última revisão:
171004
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170708
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0179576


  5 / 1823 MEDLINE  
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[PMID]:28641319
[Au] Autor:Varlet V; Dominguez A; Augsburger M; Lossois M; Egger C; Palmiere C; Vilarino R; Grabherr S
[Ad] Endereço:Forensic Chemistry and Toxicology Unit, University Centre of Legal Medicine CH-1011 Lausanne, Switzerland, vincent.varlet@chuv.ch.
[Ti] Título:Understanding scuba diving fatalities: carbon dioxide concentrations in intra-cardiac gas.
[So] Source:Diving Hyperb Med;47(2):75-81, 2017 Jun.
[Is] ISSN:1833-3516
[Cp] País de publicação:Australia
[La] Idioma:eng
[Ab] Resumo:INTRODUCTION: Important developments in the diagnosis of scuba diving fatalities have been made thanks to forensic imaging tool improvements. Multi-detector computed tomography (MDCT) permits reliable interpretation of the overall gaseous distribution in the cadaver. However, due to post-mortem delay, the radiological interpretation is often doubtful because the distinction between gas related to the dive and post-mortem decomposition artifactual gases becomes less obvious. METHODS: We present six cases of fatal scuba diving showing gas in the heart and other vasculature. Carbon dioxide (CO2) in cardiac gas measured by gas chromatography coupled to thermal conductivity detection were employed to distinguish decomposition from embolism based on the detection of decomposition gases (hydrogen, hydrogen sulfide and methane) and to confirm arterial gas embolism (AGE) or post-mortem offgasing diagnoses. A Radiological Alteration Index (RAI) was calculated from the scan. RESULTS: Based on the dive history, the intra-cadaveric gas was diagnosed as deriving from decomposition (one case, minimal RAI of 61), post-mortem decompression artifacts (two cases, intermediate RAI between 60 and 85) and barotrauma/AGE (three cases, maximal RAI between 85 and 100), illustrating a large distribution inside the bodies. CONCLUSION: MDCT scans should be interpreted simultaneously with compositional analysis of intra-cadaveric gases. Intra-cadaveric gas sampling and analysis may become useful tools for understanding and diagnosing scuba diving fatalities. In cases with short post-mortem delays, the CO2 concentration of the cardiac gas provides relevant information about the circumstances and cause of death when this parameter is interpreted in combination with the diving profile.
[Mh] Termos MeSH primário: Barotrauma/diagnóstico
Doença da Descompressão/diagnóstico
Mergulho/efeitos adversos
Afogamento/diagnóstico
Gases/análise
Tomografia Computadorizada Multidetectores
Mudanças Depois da Morte
[Mh] Termos MeSH secundário: Adulto
Idoso
Ar
Artefatos
Autopsia
Barotrauma/complicações
Dióxido de Carbono/análise
Cromatografia Gasosa
Descompressão/efeitos adversos
Afogamento/etiologia
Embolia Aérea/complicações
Embolia Aérea/diagnóstico
Artéria Femoral
Veia Femoral
Coração/diagnóstico por imagem
Seres Humanos
Hidrogênio/análise
Veias Jugulares
Masculino
Meia-Idade
Nitrogênio
Oxigênio/análise
Veia Subclávia
Condutividade Térmica
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Gases); 142M471B3J (Carbon Dioxide); 37291-87-5 (nitrox); 7YNJ3PO35Z (Hydrogen); N762921K75 (Nitrogen); S88TT14065 (Oxygen)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170808
[Lr] Data última revisão:
170808
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170623
[St] Status:MEDLINE


  6 / 1823 MEDLINE  
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[PMID]:28541191
[Au] Autor:Schwenke M; Georgii J; Preusser T
[Ad] Endereço:Fraunhofer Institute for Medical Image Computing MEVIS, Bremen, Germany.
[Ti] Título:Fast Numerical Simulation of Focused Ultrasound Treatments During Respiratory Motion With Discontinuous Motion Boundaries.
[So] Source:IEEE Trans Biomed Eng;64(7):1455-1468, 2017 Jul.
[Is] ISSN:1558-2531
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OBJECTIVE: Focused ultrasound (FUS) is rapidly gaining clinical acceptance for several target tissues in the human body. Yet, treating liver targets is not clinically applied due to a high complexity of the procedure (noninvasiveness, target motion, complex anatomy, blood cooling effects, shielding by ribs, and limited image-based monitoring). To reduce the complexity, numerical FUS simulations can be utilized for both treatment planning and execution. These use-cases demand highly accurate and computationally efficient simulations. METHODS: We propose a numerical method for the simulation of abdominal FUS treatments during respiratory motion of the organs and target. Especially, a novel approach is proposed to simulate the heating during motion by solving Pennes' bioheat equation in a computational reference space, i.e., the equation is mathematically transformed to the reference. The approach allows for motion discontinuities, e.g., the sliding of the liver along the abdominal wall. RESULTS: Implementing the solver completely on the graphics processing unit and combining it with an atlas-based ultrasound simulation approach yields a simulation performance faster than real time (less than 50-s computing time for 100 s of treatment time) on a modern off-the-shelf laptop. The simulation method is incorporated into a treatment planning demonstration application that allows to simulate real patient cases including respiratory motion. CONCLUSION: The high performance of the presented simulation method opens the door to clinical applications. SIGNIFICANCE: The methods bear the potential to enable the application of FUS for moving organs.
[Mh] Termos MeSH primário: Temperatura Corporal
Fígado/fisiopatologia
Modelos Biológicos
Mecânica Respiratória
Terapia Assistida por Computador/métodos
Terapia por Ultrassom/métodos
[Mh] Termos MeSH secundário: Simulação por Computador
Seres Humanos
Movimento
Reprodutibilidade dos Testes
Sensibilidade e Especificidade
Condutividade Térmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171023
[Lr] Data última revisão:
171023
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170526
[St] Status:MEDLINE
[do] DOI:10.1109/TBME.2016.2619741


  7 / 1823 MEDLINE  
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[PMID]:28534055
[Au] Autor:Santos MV; Sansinena M; Zaritzky N; Chirife J
[Ad] Endereço:Depto. de Ingenieria Química, Facultad de Ingenieria, Universidad Nacional de La Plata and Centro de Investigacion y Desarrollo en Criotecnologia de Alimentos (CONICET-UNLP), La Plata; Consejo Nacional de Investigaciones Científicas y Tecnicas, CABA, Argentina. mvsantosd@gmail.com.
[Ti] Título:Experimental determination of surface heat transfer coefficient in a dry ice-ethanol cooling bath using a numerical approach.
[So] Source:Cryo Letters;38(2):119-124, 2017 Mar/Apr.
[Is] ISSN:0143-2044
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Dry ice-ethanol bath (-78 degree C) have been widely used in low temperature biological research to attain rapid cooling of samples below freezing temperature. The prediction of cooling rates of biological samples immersed in dry ice-ethanol bath is of practical interest in cryopreservation. The cooling rate can be obtained using mathematical models representing the heat conduction equation in transient state. Additionally, at the solid cryogenic-fluid interface, the knowledge of the surface heat transfer coefficient (h) is necessary for the convective boundary condition in order to correctly establish the mathematical problem. OBJECTIVE: The study was to apply numerical modeling to obtain the surface heat transfer coefficient of a dry ice-ethanol bath. MATERIALS AND METHODS: A numerical finite element solution of heat conduction equation was used to obtain surface heat transfer coefficients from measured temperatures at the center of polytetrafluoroethylene and polymethylmetacrylate cylinders immersed in a dry ice-ethanol cooling bath. The numerical model considered the temperature dependence of thermophysical properties of plastic materials used. RESULTS: A negative linear relationship is observed between cylinder diameter and heat transfer coefficient in the liquid bath, the calculated h values were 308, 135 and 62.5 W/(m K) for PMMA 1.3, PTFE 2.59 and 3.14 cm in diameter, respectively. CONCLUSION: The calculated heat transfer coefficients were consistent among several replicates; h in dry ice-ethanol showed an inverse relationship with cylinder diameter.
[Mh] Termos MeSH primário: Criopreservação
Gelo-Seco
Etanol/química
Manejo de Espécimes
Propriedades de Superfície
Condutividade Térmica
[Mh] Termos MeSH secundário: Temperatura Baixa
Criopreservação/instrumentação
Criopreservação/métodos
Análise de Elementos Finitos
Modelos Teóricos
Projetos de Pesquisa
Manejo de Espécimes/instrumentação
Manejo de Espécimes/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Dry Ice); 3K9958V90M (Ethanol)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170724
[Lr] Data última revisão:
170724
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170524
[St] Status:MEDLINE


  8 / 1823 MEDLINE  
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[PMID]:28441392
[Au] Autor:Hayat T; Qayyum S; Alsaedi A; Asghar S
[Ad] Endereço:Department of Mathematics, Quaid-I-Azam University 45320, Islamabad, Pakistan.
[Ti] Título:Radiation effects on the mixed convection flow induced by an inclined stretching cylinder with non-uniform heat source/sink.
[So] Source:PLoS One;12(4):e0175584, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This study investigates the mixed convection flow of Jeffrey liquid by an impermeable inclined stretching cylinder. Thermal radiation and non-uniform heat source/sink are considered. The convective boundary conditions at surface are imposed. Nonlinear expressions of momentum, energy and concentration are transformed into dimensionless systems. Convergent homotopic solutions of the governing systems are worked out by employing homotopic procedure. Impact of physical variables on the velocity, temperature and concentration distributions are sketched and discussed. Numerical computations for skin friction coefficient, local Nusselt and Sherwood numbers are carried out. It is concluded that velocity field enhances for Deborah number while reverse situation is observed regarding ratio of relaxation to retardation times. Temperature and heat transfer rate are enhanced via larger thermal Biot number. Effect of Schmidt number on the concentration and local Sherwood number is quite reverse.
[Mh] Termos MeSH primário: Convecção
Hidrodinâmica
[Mh] Termos MeSH secundário: Algoritmos
Calefação
Temperatura Alta
Condutividade Térmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170426
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0175584


  9 / 1823 MEDLINE  
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[PMID]:28399653
[Au] Autor:Kim YH; Park LK; Yiacoumi S; Tsouris C
[Ad] Endereço:Georgia Institute of Technology, Atlanta, Georgia 30332-0373.
[Ti] Título:Modular Chemical Process Intensification: A Review.
[So] Source:Annu Rev Chem Biomol Eng;8:359-380, 2017 Jun 07.
[Is] ISSN:1947-5446
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Modular chemical process intensification can dramatically improve energy and process efficiencies of chemical processes through enhanced mass and heat transfer, application of external force fields, enhanced driving forces, and combinations of different unit operations, such as reaction and separation, in single-process equipment. These dramatic improvements lead to several benefits such as compactness or small footprint, energy and cost savings, enhanced safety, less waste production, and higher product quality. Because of these benefits, process intensification can play a major role in industrial and manufacturing sectors, including chemical, pulp and paper, energy, critical materials, and water treatment, among others. This article provides an overview of process intensification, including definitions, principles, tools, and possible applications, with the objective to contribute to the future development and potential applications of modular chemical process intensification in industrial and manufacturing sectors. Drivers and barriers contributing to the advancement of process intensification technologies are discussed.
[Mh] Termos MeSH primário: Engenharia Química/economia
Engenharia Química/métodos
Indústria Química/economia
Indústria Química/métodos
[Mh] Termos MeSH secundário: Biocombustíveis/análise
Biocombustíveis/economia
Engenharia Química/instrumentação
Indústria Química/instrumentação
Fenômenos Químicos
Eletricidade
Desenho de Equipamento
Indústria de Petróleo e Gás/economia
Indústria de Petróleo e Gás/instrumentação
Indústria de Petróleo e Gás/métodos
Som
Condutividade Térmica
Purificação da Água/economia
Purificação da Água/instrumentação
Purificação da Água/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Biofuels)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170727
[Lr] Data última revisão:
170727
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170413
[St] Status:MEDLINE
[do] DOI:10.1146/annurev-chembioeng-060816-101354


  10 / 1823 MEDLINE  
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[PMID]:28380014
[Au] Autor:Hayat T; Haider F; Muhammad T; Alsaedi A
[Ad] Endereço:Department of Mathematics, Quaid-I-Azam University, Islamabad, Pakistan.
[Ti] Título:Darcy-Forchheimer flow with Cattaneo-Christov heat flux and homogeneous-heterogeneous reactions.
[So] Source:PLoS One;12(4):e0174938, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Here Darcy-Forchheimer flow of viscoelastic fluids has been analyzed in the presence of Cattaneo-Christov heat flux and homogeneous-heterogeneous reactions. Results for two viscoelastic fluids are obtained and compared. A linear stretching surface has been used to generate the flow. Flow in porous media is characterized by considering the Darcy-Forchheimer model. Modified version of Fourier's law through Cattaneo-Christov heat flux is employed. Equal diffusion coefficients are employed for both reactants and auto catalyst. Optimal homotopy scheme is employed for solutions development of nonlinear problems. Solutions expressions of velocity, temperature and concentration fields are provided. Skin friction coefficient and heat transfer rate are computed and analyzed. Here the temperature and thermal boundary layer thickness are lower for Cattaneo-Christov heat flux model in comparison to classical Fourier's law of heat conduction. Moreover, the homogeneous and heterogeneous reactions parameters have opposite behaviors for concentration field.
[Mh] Termos MeSH primário: Condutividade Térmica
[Mh] Termos MeSH secundário: Queimaduras/etiologia
Elasticidade
Fricção
Temperatura Alta
Seres Humanos
Modelos Teóricos
Fenômenos Fisiológicos da Pele
Viscosidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170901
[Lr] Data última revisão:
170901
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170406
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0174938



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