Size-dependent mode contributions to the thermal transport of suspended and supported graphene

2019 ◽  
Vol 115 (12) ◽  
pp. 123105 ◽  
Author(s):  
Ji-Hang Zou ◽  
Xin-Tong Xu ◽  
Bing-Yang Cao
Keyword(s):  
Thermal Transport ◽  
Size Dependent

Grain-Size-Dependent Thermal Transport Properties in Nanocrystalline Yttria-Stabilized Zirconia

2001 ◽  
Vol 703 ◽  
Author(s):  
Ho-Soon Yang ◽  
J.A. Eastman ◽  
L.J. Thompson ◽  
G.-R. Bai
Keyword(s):  
Grain Boundaries ◽  
Thermal Transport ◽  
Chemical Vapor ◽  
Yttria Stabilized Zirconia ◽  
Organic Chemical ◽  
Stabilized Zirconia ◽  
Size Dependent ◽  
Metal Organic ◽  
Organic Chemical Vapor Deposition

ABSTRACTUnderstanding the role of grain boundaries in controlling heat flow is critical to the success of many envisioned applications of nanocrystalline materials. This study focuses on the effect of grain boundaries on thermal transport behavior in nanocrystalline yttria-stabilized zirconia (YSZ) coatings prepared by metal-organic chemical vapor deposition.

scholarly journals Size-dependent phononic thermal transport in low-dimensional nanomaterials

2020 ◽  
Vol 860 ◽  
pp. 1-26 ◽  
Author(s):  
Zhongwei Zhang ◽  
Yulou Ouyang ◽  
Yuan Cheng ◽  
Jie Chen ◽  
Nianbei Li ◽  
...  
Keyword(s):  
Thermal Transport ◽  
Size Dependent ◽  
Low Dimensional

Hotspot Size-Dependent Thermal Boundary Conductance in Nondiffusive Heat Conduction

2015 ◽  
Vol 137 (8) ◽  
Author(s):  
Yanbao Ma
Keyword(s):  
Thermal Transport ◽  
Critical Role ◽  
Nonlocal Effects ◽  
Thermal Boundary Conductance ◽  
Interfacial Conditions ◽  
Size Dependent ◽  
Transfer Processes ◽  
Thermal Energy Conversion ◽  
Theoretical Predictions ◽  
The Time Domain

Thermal transport across interfaces can play a critical role in nanosystems for thermal management and thermal energy conversion. Here, we show the dependence of the thermal boundary conductance (G) of the interface between a 70-nm Al transducer and a Si substrate on the size of a laser pump diameter (D) in the time-domain thermoreflectance (TDTR) experiments at room temperature. For D ≥ 30 μm, G approaches to a constant where diffusion dominates the heat transfer processes. When D decreases from 30 μm to 3.65 μm, G decreases from 240 to 170 MW/m2K due to the increasing nonlocal effects from nondiffusive heat transport. This finding is vital to our understanding of the thermal boundary conductance: it depends not only on inherent interfacial conditions but also on external heating conditions, which makes the accurate measurements and theoretical predictions of thermal transport across interfaces in micro/nanosystems more challenging.

Graphene grain size-dependent synthesis of single-crystalline Sb2Te3 nanoplates and the interfacial thermal transport analysis by Raman thermometry

Carbon ◽  
2019 ◽  
Vol 153 ◽  
pp. 164-172 ◽  
Author(s):  
Swati Singh ◽  
Seongkyun Kim ◽  
Wonjae Jeon ◽  
Krishna P. Dhakal ◽  
Jeongyong Kim ◽  
...  
Keyword(s):  
Grain Size ◽  
Thermal Transport ◽  
Single Crystalline ◽  
Size Dependent ◽  
Transport Analysis

A Hierarchical Framework for Thermal Modelling of Electronic Devices: From Atoms to Chips

2013 ◽  
Author(s):  
David A. Romero ◽  
Elham Pakseresht ◽  
Daniel Sellan ◽  
Aydin Nabovati ◽  
Cristina Amon
Keyword(s):  
Thermal Transport ◽  
Electronic Devices ◽  
Thermal Conductance ◽  
Logic Gates ◽  
Silicon Films ◽  
Thermal Modelling ◽  
Length Scales ◽  
Energy Carriers ◽  
Size Dependent ◽  
Functional Block

In this work, we provide an overview of a hierarchical computational framework to predict thermal transport in electronic devices through integration of physics-based models at different length scales. Information from atomistic simulations at the smallest length scales are transferred to upper levels of the hierarchy, up to thermal models for the chip. The proposed methodology includes five levels of length scales in electronic devices, namely (i) atomistic level, (ii) thin film and nanowire level, (iii) transistor and logic gate level, (iv) functional block level, and (v) chip level. At the first level of the hierarchy, properties of energy carriers in a semiconductor material (e.g., phonons) are obtained from atomistic level simulations, such as Molecular Dynamics (MD) and Lattice Dynamics (LD) calculations. At the second level, thermal transport in thin silicon films is modelled using a Lattice Boltzmann Method (LBM) for phonons. The outcome of these simulations is a size-dependent thermal conductivity for silicon films. At the third level of the hierarchy, these effective thermal conductivities are used in thermal modelling of logic gates. Detailed structures of different types of logic gates are reconstructed based on different manufacturing technologies (MOSFET and FinFET) at different technology nodes. Since the characteristic sizes of different parts of the logic gates are comparable to the mean free path of energy carriers, we use the size-dependent, effective thermal conductivities that were calculated at lower levels of the hierarchy to build simulation models for the logic gates. Based on these models, we calculate an equivalent thermal conductance for the logic gates, which would then be used in the upper level simulations to determine an equivalent thermal conductance for different functional blocks of the die based on their internal structure and the number and type of logic gates found in each functional block. Overall, the proposed hierarchical model enables us to include the effect of atomistic-level physics into package-level simulations, and thus, have an accurate prediction of thermal transport in an electronic device.

Production and STEM examination of controlled-size silver clusters

1983 ◽  
Vol 41 ◽  
pp. 338-339
Author(s):  
M. A. Listvan ◽  
R. P. Andres
Keyword(s):  
Cluster Size ◽  
Metal Clusters ◽  
Experimental Parameter ◽  
Carbon Films ◽  
Metal Species ◽  
Silver Clusters ◽  
Free Jet ◽  
Size Dependent ◽  
Cluster Properties ◽  
Controllable Size

Knowledge of the function and structure of small metal clusters is one goal of research in catalysis. One important experimental parameter is cluster size. Ideally, one would like to produce metal clusters of regulated size in order to characterize size-dependent cluster properties.A source has been developed which is capable of producing microscopic metal clusters of controllable size (in the range 5-500 atoms) This source, the Multiple Expansion Cluster Source, with a Free Jet Deceleration Filter (MECS/FJDF) operates as follows. The bulk metal is heated in an oven to give controlled concentrations of monomer and dimer which were expanded sonically. These metal species were quenched and condensed in He and filtered to produce areosol particles of a controlled size as verified by mass spectrometer measurements. The clusters were caught on pre-mounted, clean carbon films. The grids were then transferred in air for microscopic examination. MECS/FJDF was used to produce two different sizes of silver clusters for this study: nominally Ag6 and Ag50.

Transfer Technique for Electron Microscopy of Membrance Filter Samples

1974 ◽  
Vol 32 ◽  
pp. 554-555
Author(s):  
Lawrence W. Ortiz ◽  
Bonnie L. Isom
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Pore Size ◽  
Membrane Filters ◽  
Size Dependent

A procedure is described for the quantitative transfer of fibers and particulates collected on membrane filters to electron microscope (EM) grids. Various Millipore MF filters (Millipore AA, HA, GS, and VM; 0.8, 0.45, 0.22 and 0.05 μm mean pore size) have been used with success. Observed particle losses have not been size dependent and have not exceeded 10%. With fibers (glass or asbestos) as the collected media this observed loss is approximately 3%.

Spindle scaling mechanisms

2020 ◽  
Vol 64 (2) ◽  
pp. 383-396
Author(s):  
Lara K. Krüger ◽  
Phong T. Tran
Keyword(s):  
Cell Size ◽  
Spindle Assembly ◽  
Dependent Manner ◽  
Post Translational Modification ◽  
Size Dependent ◽  
A Cell ◽  
Chromosome Separation ◽  
Spindle Elongation ◽  
Protein Gradients ◽  
Spindle Structure

Abstract The mitotic spindle robustly scales with cell size in a plethora of different organisms. During development and throughout evolution, the spindle adjusts to cell size in metazoans and yeast in order to ensure faithful chromosome separation. Spindle adjustment to cell size occurs by the scaling of spindle length, spindle shape and the velocity of spindle assembly and elongation. Different mechanisms, depending on spindle structure and organism, account for these scaling relationships. The limited availability of critical spindle components, protein gradients, sequestration of spindle components, or post-translational modification and differential expression levels have been implicated in the regulation of spindle length and the spindle assembly/elongation velocity in a cell size-dependent manner. In this review, we will discuss the phenomenon and mechanisms of spindle length, spindle shape and spindle elongation velocity scaling with cell size.

SIZE DEPENDENT FMR LINE-SHIFT AND LINE-WIDTH STUDIES IN POLYCRYSTALLINE FERRITES AND GARNETS

1977 ◽  
Vol 38 (C1) ◽  
pp. C1-267-C1-269 ◽  
Author(s):  
C. M. SRIVASTAVA ◽  
M. J. PATNI ◽  
N. G. NANADIKAR
Keyword(s):  
Line Width ◽  
Line Shift ◽  
Size Dependent
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