15 results match your criteria confinements heat

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Evaporation in nano/molecular materials.

Adv Colloid Interface Sci 2021 Apr 23;290:102385. Epub 2021 Feb 23.

Department of Mechanical Engineering, University of Houston, 4726 Calhoun Rd, Houston, TX 77204, USA. Electronic address:

Evaporation is a physical phenomenon with fundamental significance to both nature and technology ranging from plant transpiration to DNA engineering. Various analytical and empirical relationships have been proposed to characterize evaporation kinetics at macroscopic scales. However, theoretical models to describe the kinetics of evaporation from nano and sub-nanometer (molecular) confinements are absent. Read More

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Induced Hypermigration of Primary Cortical Microglia Implicates GABAergic Signaling.

Front Cell Infect Microbiol 2019 20;9:73. Epub 2019 Mar 20.

Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden.

is a widespread obligate intracellular parasite that causes chronic infection and life-threatening acute infection in the central nervous system. Previous work identified -infected microglia and astrocytes during reactivated infections in mice, indicating an implication of glial cells in acute toxoplasmic encephalitis. However, the mechanisms leading to the spread of in the brain parenchyma remain unknown. Read More

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December 2019

Ultrafast Diameter-Dependent Water Evaporation from Nanopores.

ACS Nano 2019 Mar 11;13(3):3363-3372. Epub 2019 Mar 11.

Department of Mechanical Engineering , Boston University , Boston , Massachusetts 02215 , United States.

Evaporation from nanopores plays an important role in various natural and industrial processes that require efficient heat and mass transfer. The ultimate performance of nanopore-evaporation-based processes is dictated by evaporation kinetics at the liquid-vapor interface, which has yet to be experimentally studied down to the single nanopore level. Here we report unambiguous measurements of kinetically limited intense evaporation from individual hydrophilic nanopores with both hydrophilic and hydrophobic top outer surfaces at 22 °C using nanochannel-connected nanopore devices. Read More

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Thermoelectricity in Heterogeneous Nanofluidic Channels.

Small 2018 05 19;14(21):e1800369. Epub 2018 Apr 19.

Q. Xuesen Laboratory of Space Technology, NO. 104 Youyi Road, Haidian District, Beijing, 100094, China.

Ionic fluids are essential to energy conversion, water desalination, drug delivery, and lab-on-a-chip devices. Ionic transport in nanoscale confinements and complex physical fields still remain elusive. Here, a nanofluidic system is developed using nanochannels of heterogeneous surface properties to investigate transport properties of ions under different temperatures. Read More

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Strongly Correlated Excitons of Regular/Irregular Planar Quantum Dots in Magnetic Field: Size-Extensive Bi- and Triexciton (e-h-e-h and e-e-h/e-h-h) Systems by Multipole Expansion.

ACS Omega 2017 Oct 31;2(10):7410-7423. Epub 2017 Oct 31.

Department of Chemistry (Physical), University of Delhi, Vishwavidyalaya Marg, North Campus, 110 007 New Delhi, India.

Excitons in parabolically confined planar quantum dots with a transverse magnetic field have been studied in various model systems. The correlations between e-h, e-e, and h-h have been incorporated in terms of exact, simply elegant, and absolutely terminating finite summed Lauricella functions which eliminate the secular divergence problem and pave way for a comprehensive understanding of certain exotic phenomena of various two-dimensional regular and irregular quantum dots. A simple yet highly accurate and exact variational wave function in terms of Whittaker- function extensible to multiexcitonic systems has been propounded. Read More

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October 2017

The UTCI and the ISB.

Int J Biometeorol 2017 Sep 20;61(Suppl 1):23-27. Epub 2017 Jun 20.

Munich Re, Koeniginstraße 107, 80802, Munich, Germany.

Thermal effects of the environment are the most prominent environmental influences on the human body. Keeping the body core temperature in a narrow optimum range is the dominating physiological process. Thus, assessing thermal environments has been a major field in biometeorology for many decades, which is also reflected in the number of respective articles and their citations. Read More

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September 2017

Temperature control in large-internal-diameter scaffolded monolithic columns operated at ultra-high pressures.

J Chromatogr A 2015 Jul 11;1401:60-8. Epub 2015 May 11.

University of Amsterdam, van't Hoff Institute for Molecular Sciences, Analytical-Chemistry Group, Science Park 904, 1098 XH Amsterdam, The Netherlands.

Scaffolding makes it feasible to create organic-polymer monoliths in large confinements, such as wide-bore columns. By creating the scaffold from a metal good heat conductivity inside the column is obtained, which renders the relatively large columns (comparable with 4.6 mm i. Read More

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Atomic layer-by-layer thermoelectric conversion in topological insulator bismuth/antimony tellurides.

Nano Lett 2014 Jul 18;14(7):4030-5. Epub 2014 Jun 18.

Center for Artificial Low Dimensional Electronic Systems, Institute for Basic Science (IBS), Pohang University of Science and Technology (POSTECH) , 77 Cheongam-Ro, Pohang 790-784, Korea.

Material design for direct heat-to-electricity conversion with substantial efficiency essentially requires cooperative control of electrical and thermal transport. Bismuth telluride (Bi2Te3) and antimony telluride (Sb2Te3), displaying the highest thermoelectric power at room temperature, are also known as topological insulators (TIs) whose electronic structures are modified by electronic confinements and strong spin-orbit interaction in a-few-monolayers thickness regime, thus possibly providing another degree of freedom for electron and phonon transport at surfaces. Here, we explore novel thermoelectric conversion in the atomic monolayer steps of a-few-layer topological insulating Bi2Te3 (n-type) and Sb2Te3 (p-type). Read More

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Fabrication of uniform nanoscale cavities via silicon direct wafer bonding.

J Vis Exp 2014 Jan 9(83):e51179. Epub 2014 Jan 9.

Department of Physics, The State University of New York at Buffalo.

Measurements of the heat capacity and superfluid fraction of confined (4)He have been performed near the lambda transition using lithographically patterned and bonded silicon wafers. Unlike confinements in porous materials often used for these types of experiments(3), bonded wafers provide predesigned uniform spaces for confinement. The geometry of each cell is well known, which removes a large source of ambiguity in the interpretation of data. Read More

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January 2014

Imaginary time Gaussian dynamics of the Ar3 cluster.

J Chem Phys 2011 Jan;134(4):044107

Chemical Physics Department, Weizmann Institute of Science, 76100 Rehovot, Israel.

Semiclassical Gaussian approximations to the Boltzmann operator have become an important tool for the investigation of thermodynamic properties of clusters of atoms at low temperatures. Usually, numerically expensive thawed Gaussian variants are applied. In this article, we introduce a numerically much cheaper frozen Gaussian approximation to the imaginary time propagator with a width matrix especially suited for the dynamics of clusters. Read More

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January 2011

Cylindrical sub-micrometer confinement results for the odd-symmetric dimer alpha,omega-bis[(4-cyanobiphenyl)-4'-yloxy]undecane (BCB.O11).

J Phys Chem B 2010 Jun;114(23):7864-73

Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain.

Broadband dielectric spectroscopy (10(2) Hz to 1.9 x 10(9) Hz) and specific heat measurements have been performed on the odd-symmetric dimer alpha,omega-bis[(4-cyanobiphenyl)-4'-yloxy]undecane (BCB.O11) in the isotropic (I) and nematic (N) phases confined to 200 nm diameter parallel cylindrical pores of Anopore membranes. Read More

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Simulations of thermally induced photoacoustic wave propagation using a pseudospectral time-domain method.

IEEE Trans Ultrason Ferroelectr Freq Control 2009 May;56(5):1104-12

Most physical models used to evaluate thermally induced photoacoustic waves in biomedical applications are approximations based on assumptions necessary to obtain analytical results, such as thermal and stress confinements. In contrast, using numerical methods to solve the general photoacoustic wave equations gives detailed information on the wave phenomenon without requiring as many assumptions to be made. The photoacoustic wave generated by thermal expansion is characterized by the heat conduction theorem and the state, continuity, and Navier-Stokes equations. Read More

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Influence of cylindrical submicrometer confinement on the static and dynamic properties in nonyloxycyanobiphenyl (9OCB).

J Phys Chem B 2008 May 7;112(21):6567-77. Epub 2008 May 7.

Departamento de Física Aplicada II, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain.

Broadband dielectric spectroscopy (10(2)-1.9 x 10(9) Hz) and specific heat measurements have been performed on nonyloxycyanobiphenyl (9OCB) in the isotropic (I), nematic (N), and smectic A (SmA) phases confined to 200 nm diameter parallel cylindrical pores of Anopore membranes. Untreated and HTBA-treated membranes have been found to obtain axial and radial confinements, respectively. Read More

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Dual magnetic-/temperature-responsive nanoparticles for microfluidic separations and assays.

Langmuir 2007 Jun 16;23(13):7385-91. Epub 2007 May 16.

Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.

A stimuli-responsive magnetic nanoparticle system for diagnostic target capture and concentration has been developed for microfluidic lab card settings. Telechelic poly(N-isopropylacrylamide) (PNIPAAm) polymer chains were synthesized with dodecyl tails at one end and a reactive carboxylate at the opposite end by the reversible addition fragmentation transfer technique. These PNIPAAm chains self-associate into nanoscale micelles that were used as dimensional confinements to synthesize the magnetic nanoparticles. Read More

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Thermodynamic and dielectric studies concerning the influence of cylindrical submicrometer confinement on heptyloxycyanobiphenyl.

J Phys Chem B 2005 Dec;109(49):23209-17

Laboratori de Caracterització de Materials (LCM), Departament de Física i Enginyeria Nuclear, ETSEIB, Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona, Spain.

Measurements of the specific heat and the static dielectric permittivity of heptyloxycyanobiphenyl (7OCB) confined to the 0.2 microm diameter parallel cylindrical pores of Anopore membranes in the isotropic phase and nematic mesophase, are presented. A comparison between the bulk and the confined 7OCB in treated and untreated pore wall surfaces using a chemical surfactant (HTBA) is performed. Read More

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December 2005
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