The Chemistry and Physics of Engineering Materials

Limitations, Properties, and Models

Alexandr A. Berlin, Roman Joswik, Nikolai I. Vatin

• Publisher: Apple Academic Press
• Year: 2018
• ISBN:
  9780429843143
• Edition: 1
• Topic: Scienze biologiche
• Subtopic: Scienza generale

This new volume focuses on the limitations, properties, and models in the chemistry and physics of engineering materials that have potential for applications in several disciplines of engineering and science. Contributions range from new methods to novel applications of existing methods.

The collection of topics in this volume reflects the diversity of recent advances in chemistry and physics of engineering materials with a broad perspective that will be useful for scientists as well as for graduate students and engineers. This new book presents leading-edge research from around the world. Topics in the book include:

• aerogels materials and technology

• diffusion dynamics in nanomaterials

• entropic nomograms

• structural analyses of particulate-filled polymer nanocomposites mechanical properties

• protection of rubbers against aging

• structure-property correlation and forecast of corrosion

This volume is also sold as part of a two-volume set. Volume 1 focuses on modern analytic methodologies in the chemistry and physics of engineering materials.

CHAPTER 1

UPDATE ON AEROGELS MATERIAL AND TECHNOLOGY

MANDANA DILAMIAN and A. K. HAGHI

University of Guilan, Rasht, Iran

CONTENTS

1.1 Part I: Introduction on Concepts

1.2 Part II: Introduction on Methodology

1.3 Summary

Appendix 1: Velocity–Verlet Algorithms

Appendix 2: Monte-Carlo

Nomenclature

Keywords

References

ABSTRACT

In this chapter, different simulation methods for modeling the porous structure of silica aerogels and evaluating its structure and properties have been updated and reviewed in detail. This review has been divided in two sections. In section one, the “basic concepts” has been reviewed and in the second parts of this chapter the “research methodology” has been updated in detail.

1.1 PART 1: INTRODUCTION ON CONCEPTS

A deeper understanding of phenomena on the microscopic scale may lead to completely new fields of application. As a tool for microscopic analysis, molecular simulation methods such as the molecular dynamics (MD), Monte Carlo (MC) methods have currently been playing an extremely important role in numerous fields, ranging from pure science and engineering to the medical, pharmaceutical, and agricultural sciences. MC methods exhibit a powerful ability to analyze thermodynamic equilibrium, but are unsuitable for investigating dynamic phenomena. MD methods are useful for thermodynamic equilibrium but are more advantageous for investigating the dynamic properties of a system in a nonequilibrium situation. The importance of these methods is expected to increase significantly with the advance of science and technology. The purpose of this study is to consider the most suitable method for modeling and characterization of aerogels. Initially, giving an introduction to the Molecular Simulations and its methods help us to have a clear vision of simulating a molecular structure and to understand and predict properties of the systems even at extreme conditions. Considerably, molecular modeling is concerned with the description of the atomic and molecular interactions that govern microscopic and macroscopic behaviors of physical systems. The connection between the macroscopic world and the microscopic world provided by the theory of statistical mechanics. This is the basic of molecular simulations. There are numerous studies mentioned the structure and properties of aerogels and xerogels via experiments and computer simulations.

Computational methods can be used to address a number of the outstanding questions concerning aerogel structure, preparation, and properties. In a computational model, the material structure is known exactly and completely, and so structure/property relationships can be determined and understood directly. Techniques applied in the case of aerogels include both “mimetic” simulations, in which the experimental preparation of an aerogel is imitated using dynamical simulations, and reconstructions, in which available experimental data is used to generate a statistically representative structure. The idea of using molecular dynamics for understanding physical phenomena goes back centuries. Computer simulations are hopefully used to understand the properties of assemblies of molecules in terms of their structure and the microscopic interactions between them. This serves as a complement to conventional experiments, enabling us to learn something new, something that cannot be found out in other ways.

The main concept of molecular simulations for a given intermolecular “exactly” predict the thermodynamic (pressure, heat capacity, heat of adsorption, structure) and transport (diffusion coefficient, viscosity) properties of the system. In some cases, experiment is impossible (inside of stars weather forecast), too dangerous (flight simulation explosion simulation), expensive (high pressure simulation wind channel simulation), blind (Some properties cannot be observed on very short time-scales and very small space-scales).

The two main families of simulation technique are MD and MC; additionally, there is a whole range of hybrid techniques which combine features from both. In this lecture we shall concentrate on MD. The obvious advantage of MD over MC is that it gives a route to dynamical properties of the system: transport coefficients, time-dependent responses to perturbations, rheological properties and spectra. Computer simulations act as a bridge (Fig. 1.1) between microscopic length and time scales and the macroscopic world of the laboratory: we provide a guess at the interactions between molecules, and obtain ‘exact’ predictions of bulk properties. The predictions are ‘exact’ in the sense that they can be made as accurate as we like, subject to the limitations imposed by our computer budget. At the same time, the hidden detail behind bulk measurements can be revealed. An example is the link between the ...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• List of Contributors
• List of Abbreviations
• List of Symbols
• Preface
• About the Editors
• 1. Update on Aerogels Material and Technology
• 2. Quantum-Chemical Calculation of Pentacontacene and Hectacontacene by MNDO in Approximation of the Linear Molecular Model of Graphene
• 3. A New Concept of Photosynthesis
• 4. Entropic Nomogram
• 5. The Structural Analysis of Particulate-Filled Polymer Nanocomposites Mechanical Properties
• 6. The Reinforcement of Particulate-Filled Polymer Nanocomposites by Nanoparticles Aggregates
• 7. The Fractal Model of Polymer Pairs Adhesion
• 8. A Review on Hyaluronan Biopolymer: Properties and Pharmaceutical Applications
• 9. Oil Neutralization in the Turbulent Apparatus Confuser-Diffuser Design of Crude Oil Manufacture
• 10. Structure-Property Correlation and Forecast of Corrosion of the Alkenylarilamines Activity with the Help of Density Functional Theory
• 11. Protection of Rubbers Against Aging with the Use of Structural, Diffusion and Kinetic Effects
• Index