Classical Mechanics And Properties Of Matter By A.b. Gupta Pdf UPDATED Download

Some materials cannot be classified within the classical three states of matter. For example, liquid crystals (used in liquid-crystal displays) possess both solid-like and liquid-like properties, and belong to their own state of matter distinct from either liquid or solid.[7]

Like all known forms of matter, liquids are fundamentally quantum mechanical. However, under standard conditions (near room temperature and pressure), much of the macroscopic behavior of liquids can be understood in terms of classical mechanics.[56][58] The "classical picture" posits that the constituent molecules are discrete entities that interact through intermolecular forces according to Newton's laws of motion. As a result, their macroscopic properties can be described using classical statistical mechanics. While the intermolecular force law technically derives from quantum mechanics, it is usually understood as a model input to classical theory, obtained either from a fit to experimental data or from the classical limit of a quantum mechanical description.[59][49] An illustrative, though highly simplified example is a collection of spherical molecules interacting through a Lennard-Jones potential.[56]

Classical Mechanics And Properties Of Matter By A.b. Gupta Pdf Download

Download Zip 🔥 https://urluso.com/2y3Ia3 🔥

At extremely low temperatures, even the macroscopic behavior of certain liquids deviates from classical mechanics. Notable examples are hydrogen and helium. Due to their low temperature and mass, such liquids have a thermal de Broglie wavelength comparable to the average distance between molecules.[56]

Classical molecular dynamics (MD) simulates liquids using Newton's law of motion; from Newton's second law ( F = m x {\displaystyle F=m{\ddot {x}}} ), the trajectories of molecules can be traced out explicitly and used to compute macroscopic liquid properties like density or viscosity. However, classical MD requires expressions for the intermolecular forces ("F" in Newton's second law). Usually, these must be approximated using experimental data or some other input.[49]

Ab initio quantum mechanical methods simulate liquids using only the laws of quantum mechanics and fundamental atomic constants.[59] In contrast with classical molecular dynamics, the intermolecular force fields are an output of the calculation, rather than an input based on experimental measurements or other considerations. In principle, ab initio methods can simulate the properties of a given liquid without any prior experimental data. However, they are very expensive computationally, especially for large molecules with internal structure.

The seminar will focus on one of my most important research directions in nanomaterials, namely the physical properties of polymer-based nanocomposites. Polymer-based nanocomposites is a class of materials that typically involves polymeric matrices loaded by various nanoparticles. Frequently this definition is extended to include polymer blend, when the physical features of at least one component is controlled by submicron confinement or interfaces as well as classical composite materials, with a micron filler or larger if the surface is very thin (usually below 100 nm) and some physical properties are controlled by the interface.

Nanoindentation technique was used to investigate the nanomechanical behaviour of different soft materials. Polydimethylsiloxane (PDMS), cells and tissues were examined. The nanomechanical properties (with loading rate and creep study), namely, the hardness (?) and the elastic modulus (?) of PDMS, were determined. A classical Hertzian contact analysis was also performed in order to obtain values of ?. Moreover, the plastic deformation where no load had yet been applied to PDMS was investigated (zero load plastic deformation). Finally, the difficulties of measuring the nanomechanical properties (?&?) of cells and tissues were evaluated, showing the need for a modification of the current experimental protocols for preparing and mechanically testing in a mode that maintains their structure and their biological functioning in order to make indentation results more reproducible. Additionally, finite element method is used in order to simulate the nanoindentation of PDMS in correlation with experimental data.

Determination of the mechanical properties of soft materials is a complicated process due to their heterogeneous nature. Therefore, standard characterization methods, such as compression and tensile tests, may not be applicable due to inadequate sample dimensions. In this regard, techniques that allow the examination of the mechanical properties on a much reduced scale are needed. Nanoindentation is a technique which has been widely used to characterize the mechanical properties of materials at surface or subsurface. More specifically, through the nanoindentation experiment, the hardness (?), the elastic modulus (?), and other mechanical properties can be determined from very small volumes of materials. The high spatial resolution of nanoindentation allows local testing of mechanical properties of soft matter that is not possible using macroscale techniques. For this reason, the application of nanoindentation to soft materials has increased over recent years [2].

Our research centers on problems at the interface of quantum and statistical mechanics. Particular themes that occur frequently in our research are hydrogen bonding, the interplay between structure and dynamics, systems with multiple time and length-scales and quantum mechanical effects. The applications of our methods are diverse, ranging from chemistry to biology to geology and materials science. Particular current interests include proton and electron transfer in fuel cells and enzymatic systems, atmospheric isotope separation and the control of catalytic chemical reactivity using electric fields.

Treatment of these problems requires a range of analytic techniques as well as molecular mechanics and ab initio simulations. We are particularly interested in developing and applying methods based on the path integral formulation of quantum mechanics to include quantum fluctuations such as zero-point energy and tunneling in the dynamics of liquids and glasses. This formalism, in which a quantum mechanical particle is mapped onto a classical "ring polymer," provides an accurate and physically insightful way to calculate reaction rates, diffusion coefficients and spectra in systems containing light atoms. Our work has already provided intriguing insights in systems ranging from diffusion controlled reactions in liquids to the quantum liquid-glass transition as well as introducing methods to perform path integral calculations at near classical computational cost, expanding our ability to treat large-scale condensed phase systems.

Influence of chain length on structural properties of carbon molecularsieving membranes and their effects on CO2, CH4 and N2 adsorption: Amolecular simulation study, S Dasgupta and M Rajasekaran and PK Roy andFM Thakkar and AD Pathak and KG Ayappa and PK Maiti, JOURNAL OF MEMBRANESCIENCE, 664, 121044 (2022). (DOI: 10.1016/j.memsci.2022.121044)(abstract)

A computational study on the mechanical properties of Pentahexoctitesingle-layer: Combining DFT and classical molecular dynamicssimulations, WHS Brandao and AL Aguiar and LA Ribeiro and DS Galvao andJM De Sousa, CHEMICAL PHYSICS, 563, 111686 (2022). (DOI:10.1016/j.chemphys.2022.111686)(abstract)

To the best of our knowledge, there is no theoretical work available in theliterature on the detailed physical properties of the Lave phase LaCo2compound, which is the central focus of our paper. In this study, we haveinvestigated the structural, elastic and electronic properties of theLaCo2 intermetallic compounds in cubic C15 (MgCu2 ) phaseusing first principle calculations, which are followed by the transport propertiesusing semi-classical Boltzmann theory in order to deeply understand the ground-stateproperties and provide accurate theoretical results. 2351a5e196