Nonequilibrium Thermodynamics of the First andSecondKind: AveragesandFluctuations

We elaborate and compare two approaches to nonequilibrium thermodynamics, the two-generator bracket formulation of time-evolution equations for averages and the macroscopic fluctuation theory, for a purely dissipative isothermal driven diffusive system under steady state conditions. The fluctuation dissipation relations of both approaches play an important role for a detailed comparison. The nonequilibrium Helmholtz free energies introduced in these two approaches differ as a result of boundary conditions. A Fokker-Planck equation derived by projection operator techniques properly reproduces long range fluctuations in nonequilibrium steady states and offers the most promising possibility to describe the physically relevant fluctuations around macroscopic averages for time-dependent nonequilibrium system

Radioisotope: Applications, Effects, and Occupational Protection

This chapter presents a brief introduction to radioisotopes, sources and types of radiation, applications, effects, and occupational protection. The natural and artificial sources of radiations are discussed with special reference to natural radioactive decay series and artificial radioisotopes. Applications have played significant role in improving the quality of human life. The application of radioisotopes in tracing, radiography, food preservation and sterilization, eradication of insects and pests, medical diagnosis and therapy, and new variety of crops in agricultural field is briefly described. Radiation interacts with matter to produce excitation and ionization of an atom or molecule; as a result physical and biological effects are produced. These effects and mechanisms are discussed. The dosimetric quantities used in radiological protection are described. Radiological protections and the control of occupational and medical exposures are briefly described

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 182, July 1978

This bibliography lists 165 reports, articles, and other documents introduced into the NASA scientific and technical information system in June 1978

Flame Retardants

Flame retardants reduce the risk of fire by decreasing the combustion rate and flame propagation in the presence of fire, leading to the prevention and control of fire. Flame Retardants is divided into four sections: section 1 consists of the introduction, section 2 discusses properties, Section 3 comprises nanocomposites, and section 4 includes computational analysis. The book will be useful for scientists and researchers interested in the field of fire control

Artificial intelligence for porous organic cages

Porous organic cages are a novel class of molecules with many promising applications, including in separation, sensing, catalysis and gas storage. Despite great promise, discovery of these materials is hampered by a lack of computational tools for exploring their chemical space, and significant expense associated with prediction of their properties. This results in significant synthetic effort being directed toward molecules which do not have targeted properties. This thesis presents multiple computational tools which can aid the discovery and design of these materials by increasing the number of synthetic candidates which are likely to exhibit desired, targeted properties. Firstly, a broadly applicable methodology for the construction of computational models of materials is presented. This facilitates the automated modelling and screening of materials that would otherwise have to be carried out in a more labour-intensive way. Secondly, an evolutionary algorithm is implemented and applied to the design of porous organic cages. The algorithm is capable of producing cages closely matching user-defined design criteria, and its implementation is designed to allow future applications in other fields of material design. Finally, machine learning is used to accurately predict properties of porous organic cages, orders of magnitude faster than has been possible with traditional, simulation-based approaches.Open Acces

MODEL-BASED CONTROL WITH STOCHASTIC SIMULATORS: BUILDING PROCESS DESIGN AND CONTROL SOFTWARE FOR CATALYTICALLY ENHANCED MICROSYSTEMS

The production, characteristics, dynamics, and economics of microreactors were studied in this report. Overall it was found that the best microfabrication techniques for small scale processes were laser ablation, the LIGA process, soft lithography, and anisotropic wet chemical etching, roughly in ascending order of effectiveness. One of the few viable bonding techniques was found to be diffusion bonding followed by microlamination, whereas many coating methods -- such as solgel coating, modified anodic oxidation, and electrophoretic deposition -- were effective in μTAS integration. The high surface area to volume ratio of microreactors enables precise control of the temperature of the reactor along its axial dimension. Taking advantage of this feature in the design of microreactors leads to better control of complex reaction networks and generates more valuable effluent streams. A model predictive controller was implemented for the common, archetypical reaction network involving the hydrogenation and dehydrogenation of cyclohexene with various control objectives. It was found that the highest rate of production of benzene and cyclohexane occurred at 600 K while the most pure stream of benzene occurred at 200 K. Model predictive control was found to be highly resistant to the inherent stochasticity of small scale processes. The market for a software-based controller for microreactors was surveyed and found to still be in the early stages of development. A profitability analysis was conducted for a start-up company using microreactors to make cyclohexane. A price of $18,000 for the product was found to be a reasonable selling price yet allowed the start-up to remain profitable