Bibliographies thématiques / Novel Nano-structures -Ab-initio Study

Littérature scientifique sur le sujet « Novel Nano-structures -Ab-initio Study »

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Publié le 7 septembre 2023

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Articles de revues sur le sujet "Novel Nano-structures -Ab-initio Study"

Hu, Hang, et Alejandro D. Rey. « Multi-step modeling of liquid crystals using ab initio molecular packing and hybrid quantum mechanics/molecular mechanics simulations ». Journal of Theoretical and Computational Chemistry 16, n^o 02 (mars 2017) : 1750012. http://dx.doi.org/10.1142/s0219633617500122.

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A density functional theory (DFT) based multi-step simulation method is used to characterize the detailed molecular structure and inter/intra- molecular interactions of two benchmark liquid crystals (LC) 5CB, 8CB and a novel tri-biphenyl ring bent core LC material. The method uses hybrid DFT at the B3LYP/6-31G* level to obtain molecular structure and Raman data. These results are fed to a crystal packing simulation to find possible crystal structures. A pico-second quantum mechanics/molecular mechanics (QM/MM) simulation model is built for the selected structures with lower overall energy as well as optimal density. The stabilized crystal structures are then extended into a super cell, heated and simulated using a mixed force field and nano-second molecular dynamics (MD). The described simulation process sequence provides predictions of molecular Raman spectrum, LC density, isotropic depolarization ratio, ratio of differential polarizability, order parameters, molecular structures, and rotating Raman spectrum of the different mesophases. The Raman spectra, order parameters and depolarization ratios all agree well with existing experimental and previous simulation results. The study of the novel tri-biphenyl ring bent core LC system shows that the ratio of differential polarizability depends on intra-molecular interactions. The findings presented in this manuscript contribute to the on-going efforts to establish links between LC molecular structures and their properties, including optical behavior.

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Xiao, Chengliang, Zaiyu Xiao, Cuifang Hu, Jie Lu, Liwei Cui, Yang Zhang, Yujie Dai, Qinghua Zhang, Sheng Wang et Wei Liu. « Crystal and solution structures of a novel antimicrobial peptide from Chrysomya megacephala ». Acta Crystallographica Section D Structural Biology 77, n^o 7 (18 juin 2021) : 894–903. http://dx.doi.org/10.1107/s2059798321004629.

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Antimicrobial peptides (AMPs) are small amphipathic peptides that exhibit bactericidal activity against a wide range of pathogenic microorganisms and are considered to be potential substitutes for antibiotics effective against microbial infection. PSK, an 84-amino-acid AMP recently isolated from Chrysomya megacephala larvae, probably belongs to the mitochondrial ATPase inhibitor family according to its sequence. No member of this family from an insect has been structurally characterized to date. In this study, the crystal structure of full-length PSK determined by molecular replacement using an ab initio modeled ensemble as a search model and a solution structure obtained from small-angle X-ray scattering (SAXS) measurements are reported. The crystal structure reveals a distinct fold compared with those of homologous peptides, in that PSK comprises two antiparallel α-helices rather than a single long helix, which is in good agreement with the SAXS-based ab initio model. However, the peptide exists as a monomer in solution, even though a stable dimer was observed in the crystal structure. This apparent contradiction may reflect different oligomerization states that may be implicated in its bioactivity. The data presented here have established a solid basis for further mechanistic studies of this novel insect AMP.

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Kurt, Barış, et Hamdi Temel. « Parameterization of Boronates Using VFFDT and Paramfit for Molecular Dynamics Simulation ». Molecules 25, n^o 9 (8 mai 2020) : 2196. http://dx.doi.org/10.3390/molecules25092196.

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Boric acid, borate esters, and hydroxy derivatives are biologically active molecules. Thus, performing molecular dynamics simulations of these molecules is vital in terms of drug design, but it is difficult to find directly generated Amber parameters based on an ab initio method for these kinds of molecules in the literature. In this study, Amber parameters for such molecules containing boron were generated based on ab initio calculations using the paramfit program, which applies a combination of genetic and simplex algorithms, and the Visual Force Field Derivation Toolkit (VFFDT) program containing the Seminario method. The minimized structure, after obtaining novel parameters and using the sander program, was compared with the experimental crystallographic structures, and it was observed that the root-mean-square deviation (RMSD) value between the experimental structure and minimized structure agreed reasonably well. In addition, the molecule was heated, and the molecular dynamics simulation was successfully obtained with the novel parameters.

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Hammou, M., F. Bendahma, M. Mana, S. Terkhi, N. Benderdouche, Z. Aziz et B. Bouhafs. « Thermoelectric and Half-Metallic Behavior of the Novel Heusler Alloy RbCrC : Ab initio DFT Study ». SPIN 10, n^o 04 (décembre 2020) : 2050029. http://dx.doi.org/10.1142/s2010324720500290.

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Research Highlights • Electronic, magnetic, elastic and thermoelectric properties of RbCrC alloy are investigated. • Material is half-metallic, ductile and anisotropic in nature. • The total magnetic moment (3[Formula: see text][Formula: see text]B) obeys the Slater–Pauling rule. • The HM RbCrC compound is identified as potential candidate for spintronic applications. • ZT calculated values of 0.89 and 0.94 make RbCrC a promising thermoelectric material candidate for use in future devices. The aim of this work is to investigate the half-metallicity behavior, elastic, thermodynamic and thermoelectric (TE) properties of the Heusler compound RbCrC using the generalized gradient approximation (GGA-PBE96) and the modified Becke–Johnson (mBJ) approach. The electronic band structures and density of states reveal that RbCrC is a half-metallic ferromagnet (HMF). The calculated total magnetic moment of 3[Formula: see text][Formula: see text]B follows the Slater–Pauling rule ([Formula: see text]). The half-metallicity character can be maintained in the 5.4–7.4 Å lattice constants range and the 0.8–1.2 [Formula: see text]/[Formula: see text] ratio range. Existence of half-metallic ferromagnetism in RbCrC makes it a promising material for practical applications in the spintronic field. Also, the RbCrC exhibits a ductile and anisotropic behavior. The quasi-harmonic Debye model (QHDM) is used to calculate the thermodynamic properties. The BoltzTraP code which is based on semi-classical Boltzmann theory (SCBT) is applied for calculating TE properties. According to the obtained figure of merit values (ZT between 0.89 and 0.94 from 50 K to 800 K), the RbCrC alloy remains a good candidate for thermoelectric applications.

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Bakhshi, A. K., et Geetika Gandhi. « Ab initio study of the electronic structures and conduction properties of some novel low band-gap donor–acceptor polymers ». Solid State Communications 129, n^o 5 (février 2004) : 335–40. http://dx.doi.org/10.1016/j.ssc.2003.10.013.

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Fu, Yudong, Zifeng Li, Weihong Gao, Danni Zhao, Zhihao Huang, Bin Sun, Mufu Yan, Guotan Liu et Zihang Liu. « Exploring Hydrogen Incorporation into the Nb4AlC3 MAX Phases : Ab Initio Calculations ». Materials 15, n^o 21 (28 octobre 2022) : 7576. http://dx.doi.org/10.3390/ma15217576.

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The Nb4AlC3 MAX phase can be regarded as a TMC structure with stacking faults, which has great potential as a novel solid hydrogen storage material. Herein, we used ab initio calculations for understanding the hydrogen incorporation into Nb4AlC3 MAX phases, including equilibrium structural characteristics, energy changes, electronic structures, bonding characteristics, and diffusion paths. According to the calculated results, H has thermal stability in the interstice of the Nb-Al layer, and the most probable insertion site is an octahedron (3-site) composed of three Nb atoms and three Al atoms. When C vacancies are introduced, the Nb-C layer has a specific storage capacity for H. In addition, Al vacancies can also be used as possible sites for H incorporation. Moreover, the introduction of vacancies significantly increase the hydrogen storage capacity of the MAX phase. According to the electronic structure and bonding characteristics, the excellent hydrogen storage ability of the Nb4AlC3 structure may be due to the formation of ionic bonds between H and Nb/Al. It is worth noting that the H-Al bond in the 1-site is a covalent bond and an ionic bond key mixture. The linear synchronous transit optimization study shows that only H diffusion in Al vacancies is not feasible. In conclusion, the Nb-Al layer in Nb4AlC3 can provide favorable conditions for the continuous insertion and subsequent extraction of H, while the vacancy structure is more suitable for H storage. Our work provides solid theoretical results for understanding the hydrogen incorporation into Nb4AlC3 MAX phases that can be helpful for the design of advanced hydrogen storage materials.

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Jovanović, Dušica, Dejan Zagorac, Branko Matović, Aleksandra Zarubica et Jelena Zagorac. « Anion substitution and influence of sulfur on the crystal structures, phase transitions, and electronic properties of mixed TiO2/TiS2 compounds ». Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 77, n^o 5 (22 septembre 2021) : 833–47. http://dx.doi.org/10.1107/s2052520621008891.

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Recent studies of TiO2/TiS2 nanostructures with various morphologies have been reported, usually showing improved properties with applications from electronics and catalysis to solar cells and medicine. However, there is a limited number of studies on the crystal structures of TiO2/TiS2 compounds with corresponding properties. In this research, relevant crystal structures of TiO1–x S x (x = 0, 0.25, 0.5, 0.75 and 1) solid solutions were investigated using an ab initio method. For each composition, crystal structures adopting anatase, rutile and CdI2 structure type were calculated on LDA-PZ and GGA-PBE levels of theory. Novel phase transitions and predicted structures are presented, and apart from several interesting metastable structures, a very interesting pressure-induced phase transition is found in the TiOS compound. Furthermore, electronic properties were studied through the dependence of semiconducting properties on dopant concentration. The first description of the electronic properties of the mixed TiO1–x S x compounds in crystal form has been presented, followed by a detailed study of the structure–property relationship, which will possibly have numerous industrial and technological applications.

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Kazerounian, Kazem, Khalid Latif, Kimberly Rodriguez et Carlos Alvarado. « Nano-Kinematics for Analysis Of Protein Molecules ». Journal of Mechanical Design 127, n^o 4 (5 août 2004) : 699–711. http://dx.doi.org/10.1115/1.1867956.

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Proteins are evolution’s mechanisms of choice. The study of nano-mechanical systems must encompass an understanding of the geometry and conformation of protein molecules. Proteins are open or closed loop kinematic chains of miniature rigid bodies connected by revolute joints. The Kinematics community is in a unique position to extend the boundaries of knowledge in nano biomechanical systems. In this work, we have presented a comprehensive methodology for kinematics notation and direct kinematics for protein molecules. These methods utilize the zero-position analysis method and draws upon other recent advances in robot manipulation theories. The procedures involved in finding the coordinates of every atom in the protein chain as a function of the dihedral and Rotamer angles are computationally the most efficient formulation developed to date. The notation and the methodologies of this paper are incorporated in the computer software package PROTOFOLD and will be made available to individuals interested in using it. PROTOFOLD is a software package that implements novel and comprehensive methodologies for ab initio prediction of the final three-dimensional conformation of a protein, given only its linear structure. In addition to the new kinematics methodologies mentioned above, we have also included all the basic kinematic parameter values that are needed in any kinematic analysis involving proteins. While these values are based on a body of knowledge recorded in the protein data bank, they are presented in a form conducive to kinematics.

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Kaiser, Dietmar, Georgi Videnov, Cäcilia Maichle-Mössmer, Joachim Strähle et Günther Jung. « X-Ray structures and ab initio study of the conformational properties of novel oxazole and thiazole containing di- and tripeptide mimetics † ». Journal of the Chemical Society, Perkin Transactions 2, n^o 5 (2000) : 1081–85. http://dx.doi.org/10.1039/a909842i.

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Wu, Guanzhao, Yangxue Liu, Zhen Yang, Liulei Ma, Yao Tang, Xianliang Zhao, Hossein Rouh et al. « Triple-Columned and Multiple-Layered 3D Polymers : Design, Synthesis, Aggregation-Induced Emission (AIE), and Computational Study ». Research 2021 (8 février 2021) : 1–13. http://dx.doi.org/10.34133/2021/3565791.

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Conjugated polymers and oligomers have great potentials in various fields, especially in materials and biological sciences because of their intriguing electronic and optoelectronic properties. In recent years, the through-space conjugation system has emerged as a new assembled pattern of multidimensional polymers. Here, a novel series of structurally condensed multicolumn/multilayer 3D polymers and oligomers have been designed and synthesized through one-pot Suzuki polycondensation (SPC). The intramolecularly stacked arrangement of polymers can be supported by either X-ray structural analysis or computational analysis. In all cases, polymers were obtained with modest to good yields, as determined by GPC and 1H-NMR. MALDI-TOF analysis has proven the speculation of the step-growth process of this polymerization. The computational study of ab initio and DFT calculations based on trimer and pentamer models gives details of the structures and the electronic transition. Experimental results of optical and AIE research confirmed by calculation indicates that the present work would facilitate the research and applications in materials.

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Plus de sources

Thèses sur le sujet "Novel Nano-structures -Ab-initio Study"

« Ab initio study of the structures, reactions, and energetics of some novel chemical species ». 1999. http://library.cuhk.edu.hk/record=b5889892.

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Lau Kai-Chung.
Thesis (M.Phil.)--Chinese University of Hong Kong, 1999.
Includes bibliographical references.
Abstracts in English and Chinese.
Abstract
Acknowledgements
Table of Contents
Chapter Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- The Gaussian-2 Method
Chapter 1.2 --- The G2 Method with Reduced M φller-Plesset Order and Basis Set
Chapter 1.3 --- The Gaussian-3 Method
Chapter 1.4 --- Our Modified G2 Methods
Chapter 1.5 --- Calculation of Thermodynamical Data
Chapter 1.6 --- Scope of the Thesis
Chapter 1.7 --- Remark on the Location of Transition Structures
Chapter 1.8 --- References
Chapter Chapter 2 --- A Gaussian-2 Study of the [C2H5O-] Potential Energy Surface and the Fragmentation Pathways of the Ethoxide Anion --- p.7
Chapter 2.1 --- Introduction
Chapter 2.2 --- Theoretical Methods
Chapter 2.3 --- Results and Discussion
Chapter 2.3.1 --- Stable Isomers and TSs for the [C2H50-] Anions
Chapter 2.3.2 --- Fragmentation Pathways of the Ethoxide Anion (1-)
Chapter 2.4 --- Conclusions
Chapter 2.5 --- Publication Note
Chapter 2.6 --- References
Chapter Chapter 3 --- A Gaussian-2 Study of Isomeric C2H2N and C2H2N+ --- p.20
Chapter 3.1 --- Introduction
Chapter 3.2 --- Theoretical Methods
Chapter 3.3 --- Results and Discussion
Chapter 3.3.1 --- The C2H2N and C2H2N+ Isomers
Chapter 3.3.2 --- The Cyanomethyl Radical (1) and Cation (1+)
Chapter 3.3.3 --- The Isocyanomethyl Radical (2) and Cation (2+)
Chapter 3.3.4 --- The lH-Azirinyl Radical (5) and Cation (5+)
Chapter 3.3.5 --- Other C2H2N and C2H2N+ Isomers
Chapter 3.3.6 --- The Unidentified C2H2N Isomer Formed in N + CH=CH2
Chapter 3.4 --- Conclusions
Chapter 3.5 --- Publication Note
Chapter 3.6 --- References
Chapter Chapter 4 --- A Gaussian-2 Study of the Photoionization and Dissociative Photoionization Channels of Ethylene Oxide --- p.35
Chapter 4.1 --- Introduction
Chapter 4.2 --- Theoretical Methods
Chapter 4.3 --- Results and Discussion
Chapter 4.3.1 --- Bond Cleavage Reactions
Chapter 4.3.2 --- Dissociation Channels Involving Transition Structure(s)
Chapter 4.4 --- Conclusions
Chapter 4.5 --- Publication Note
Chapter 4.6 --- References
Chapter Chapter 5 --- A Gaussian-2 Study of the Photoionization and Dissociative Photoionization Channels of Propylene Oxide --- p.47
Chapter 5.1 --- Introduction
Chapter 5.2 --- Theoretical Methods
Chapter 5.3 --- Results and Discussion
Chapter 5.3.1 --- Bond Cleavage Reactions
Chapter 5.3.2 --- Dissociation Channels Involving Transition Structure(s)
Chapter 5.4 --- Conclusions
Chapter 5.5 --- Publication Note
Chapter 5.6 --- References
Chapter Chapter 6 --- A Gaussian-3 Study of the Thermochemistry of Chlorofluoromethanes (CFnCl4-n) and Their Cations (CFnCl4_n+)， n =0-4 --- p.61
Chapter 6.1 --- Introduction
Chapter 6.2 --- Theoretical Methods
Chapter 6.3 --- Results and Discussions
Chapter 6.3.1 --- Heats of Formation of Chlorofluoromethanes and Their Cations
Chapter 6.3.2 --- Ionization Energies of Chlorofluoromethanes
Chapter 6.3.3 --- Proton Affinities of Chlorofluoromethanes
Chapter 6.4 --- Conclusions
Chapter 6.5 --- Publication Note
Chapter 6.6 --- References
Chapter Chapter 7 --- "A Gaussian-2 and Gaussian-3 Study of the Energetics and Structures of Cl2On and Cl2On+, n = 1，4, 6，and7" --- p.69
Chapter 7.1 --- Introduction
Chapter 7.2 --- Theoretical Methods
Chapter 7.3 --- Results and Discussion
Chapter 7.3.1 --- Cl20 and Cl20+
Chapter 7.3.2 --- Cl204 and Cl204+
Chapter 7.3.3 --- Cl206 and Cl206+
Chapter 7.3.4 --- Cl207 and Cl207+
Chapter 7.4 --- Conclusions
Chapter 7.5 --- Publication Note
Chapter 7.6 --- References
Chapter Chapter 8 --- Conclusions --- p.81
Chapter Appendix A --- The Gaussian-n (n = 1 - 3) Theoretical Models --- p.82
Chapter A.1 --- The G1 and G2 theories
Chapter A.2 --- The G2(MP2) theory
Chapter A.3 --- "The G2(MP2,SVP) theory"
Chapter A.4 --- The G3 theory
Chapter Appendix B --- "Calculation of Enthalpy at 298 K, H298" --- p.86

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Actes de conférences sur le sujet "Novel Nano-structures -Ab-initio Study"

Al Hashimi, Husain, et Jungho Kim. « Quantum Dot Temperature Sensor Ab Initio Test : Droplet Vaporization Heat Transfer ». Dans ASME 2016 Heat Transfer Summer Conference collocated with the ASME 2016 Fluids Engineering Division Summer Meeting and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ht2016-7164.

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Better understanding of phase change phenomena can be obtained through local measurements of the heat transfer process, which can’t be attained by traditional thermocouple point measurements. Infrared (IR) technology, which has been used by many researchers in the past, cannot be used under certain circumstances due to spectral transparency issues present in some materials. In the current study, Quantum Dots (QDs) are proposed as a novel tool for heat transfer measurements. QDs are nano-sized semiconductor materials which fluoresce upon excitation by blue or UV light. The light intensity emitted by QDs drops with temperature, which can be utilized to obtain the surface temperature distribution at a camera pixel resolution. If QDs are distributed on a surface of interest and optical access to that surface is available, the heat transfer processes can be examined using inexpensive equipment such as CCD/CMOS cameras and LED excitation sources. In this paper, a description of a QD based technique is given, where it is applied to visualize the heat transfer associated with ethanol droplet evaporation.

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Kazerounian, Kazem, Khalid Latif, Kimberly Rodriguez et Carlos Alvarado. « ProtoFold : Part I — Nanokinematics for Analysis of Protein Molecules ». Dans ASME 2004 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/detc2004-57243.

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Proteins are evolution’s mechanisms of choice. Study of nano-mechanical systems must encompass an understanding of the geometry and conformation of protein molecules. Proteins are open or closed loop kinematic chains of miniature rigid bodies connected by revolute joints. The Kinematics community is in a unique position to extend the boundaries of knowledge in nano biomechanical systems. ProtoFold is a software package that implements novel and comprehensive methodologies for ab initio prediction of the final three-dimensional conformation of a protein, given only its linear structure. In this paper, we present the methods utilized in the kinematics notion and kinematics analysis of protein molecules. The kinematics portion of ProtoFold incorporates the Zero-Position Analysis Method and draws upon other recent advances in robot manipulation theories. We claim that the methodology presented is a computationally superior and more stable alternative to traditional molecular dynamics simulation techniques.

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YANAMANDRA, KAUSHIK, RAKESH K. BEHERA et NIKHIL GUPTA. « INFLUENCE OF CARBON IN LEAD MATRIX FOR LEAD ACID BATTERY APPLICATION : A DENSITY FUNCTIONAL THEORY APPROACH ». Dans Thirty-sixth Technical Conference. Destech Publications, Inc., 2021. http://dx.doi.org/10.12783/asc36/35762.

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Recent research in developing novel lead electrodes composed of carbon and lead composites have shown potential of increasing the ability of lead-acid batteries to store energy in grid scale applications but many technical challenges persist. One challenging obstacle is that influence of carbon on lead matrix in these new battery systems are obscure and the mechanism taking place at the atomic level is difficult to investigate experimentally. However, a better understanding of the working mechanisms of battery materials is crucial for developing new advanced batteries toward industrial applications. In this paper the density functional theory (DFT) calculation are carried out using the Vienna Ab-initio Simulation Package (VASP) with spin-polarized generalized gradient approximation (GGA) functional parametrized by Perdew, Burke, and Enrzerhof (PBE) is used to describe the exchange and correlation energies of the electrons. Herein, a systematic increase in system site with decrease in C concentration was investigated in Pb using DFT. This study provides vital fundamental data on Pb-C structure such as density of states, band structures, defect formation energies.

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Luo, Tengfei, et John R. Lloyd. « Ab-Initio Molecular Dynamics Study of Nano-Scale Thermal Energy Transport ». Dans ASME 2007 2nd Energy Nanotechnology International Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/enic2007-45033.

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Ab-initio molecular dynamics (MD) which employs density functional theory (DFT) is used to study thermal energy transport phenomena in nano-scale structures. Thermal equilibration in multiple thin layer structures with thicknesses less than 1 nanometer per layer is simulated. Different types of layer combinations are investigated. Periodic boundary conditions in all directions are used in all cases. Two neighboring layers are first set to different temperatures using Nose-Hoover thermostats, and then the process of energy equilibration is simulated with a “free run” (without any thermostat controlling the temperatures). The temperature evolutions in the two neighboring layers are computed. The atomic vibration power spectra are calculated and used to explain the phenomena observed in the simulation.

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Singh, Hardev, Mukhtiyar Singh, Manish K. Kashyap, S. K. Tripathi, Keya Dharamvir, Ranjan Kumar et G. S. S. Saini. « Ab-initio Study of Electronic Band Structures of CdBAs[sub 2] (B = Si, Ge and Sn) Chalcopyrite Compounds ». Dans INTERNATIONAL CONFERENCE ON ADVANCES IN CONDENSED AND NANO MATERIALS (ICACNM-2011). AIP, 2011. http://dx.doi.org/10.1063/1.3653663.

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Banerjee, Sauvik, Mutasem Shehadeh, Gang Lu, Nicholas Kioussis et Nasr Ghoniem. « A Multiscale Approach for the Determination of Nonsingular Elastic Fields of Dislocations in Bulk and Nano-Layered Materials ». Dans ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-42058.

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The traditional description of elastic field and energies of dislocations is based on continuum theory of linear elasticity that suffers from the long-standing problem of singularities at the dislocation core. Singular solutions are often circumvented by introducing an artificial core-cutoff radius. This limits the applicability of the theory to describe situations where it is important to know the strained state and nanoscopic details within a few atomic spacings surrounding the dislocation center, known as the dislocation core. In this paper, a computationally tractable multiscale approach is developed to calculate the nonsingular elastic fields of dislocations in both bulk and nano-layered materials. The approach is an extension of Peierls-Nabarro (PN) model, with the following features: (1) all three components of the displacement vector for atoms within the dislocation core are included; (2) the entire generalized stacking fault energy (GSFE or gamma-γ) surface obtained from ab initio calculations is utilized; and (3) the method can be generalized to treat curved dislocations. We combine the parametric dislocation dynamics (DD) approach for the interaction and motion of dislocations with the ab initio calculations of the lattice restoring forces, which are extracted from the γ surface. The method is used to study two important problems: (a) dislocation dissociation in bulk crystals (b) dislocation transmission across interfaces in elastic bimaterials. Dislocation core structures in bulk aluminum and silver are determined. The results from the model are shown to be in excellent agreement with experiments for both Al and Ag. For bi-materials system, the effects of the mismatch in the elastic properties, γ surface and lattice parameters on the spreading of the dislocation onto the interface(s) and the transmission across the interface(s) are studied in detail.

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