Processing and Properties of Compound Semiconductors,73
Ceramic materials and single crystals showing ferroelectric behavior are being used in many applications in electronics and optics. A large number of applications of ferroelectric ceramics also exploit properties that are an indirect consequence of ferroelectricity, such as dielectric, piezoelectric, pyroelectric and electro-optic properties. This book introduces the basic principles and characteristics of ferroelectric materials and lists various materials chosen from single crystals, ceramics, polymers and ceramic-polymer composites which show ferroelectric behavior. Many different applications arising from ferroelectricity and related phenomena in ceramics and thin films have been discussed with their processing techniques
An Annotated Bibliography on Microwaves – Their Properties, Production & Applications to Food Processing
Cassava starch is a better substitute for maize starch but processing of cassava starch into pellet is a better form of handling. Thus, this study to investigate the effects of some machine parameters and the moisture content of preparation of cassava dough on some physical and mechanical properties of cassava pellets Result shows that quality pellets can be obtained when cassava dough is conditioned into moisture contents level of above 48.5%wb and moisture content level of below 55.5%wb. The study shows that cassava dough can successfully be used to obtain quality cassava pellets.
Knowledge about the thermal, rheological properties, mechanical properties, textural characteristics and physical properties of food materials have an important role from the stand point of engineering during processing of such materials. So, study of thermal and rheological properties, including determination of rheological and thermal parameters, is very important and the rheological parameters are very essential in designing the required equipments for handling and processing of the food materials. Also viscosity is usually considered an important physical property related to the quality of food products. Viscometric data are also essential for the design evaluation of food processing equipment such as pumps, piping, heat exchangers, evaporators, sterilizes filters and mixtures. Information on the mechanical properties of fruits and vegetables is of use in characterisation of material, fixing optimum time for harvest, separation from undesirable materials, texture and quality evaluation, assessment of the extent and nature of damage in collection, handling, and storage and processing, and identification of basic anatomical structure.
Physical properties of food is fundamental in analyzing the unit operations applied in the food industry. The study of these food properties and their responses to process conditions is necessary because they influence of the treatment received during the processing also because they are good indicators of other properties and qualities of food. Viscosity and its variation with concentration and temperature are very important for the food industry in general and for fruit derivatives in particular, since it is necessary for the design and the optimization of several processing operations (e.g., pumping, evaporation, membrane filtration).
Synthetic fibers are generally used to make composite materials for their better mechanical and thermal properties. However, they are expensive and non-biodegradable. Alternatively, natural fibers are inexpensive, biodegradable, easily available in nature and have good mechanical, and thermal. Among all natural fibers, jute fibers are easily available in fabric and fiber forms with good mechanical and thermal properties. Therefore, jute-based composite materials can be used in consumer goods, low-cost housing, cars, and civil structures. Jute fibers are chemically treated to improve fiber/matrix interface adhesion and moisture induced degradation. Biodegradable composites are manufactured using jute fabrics, biodegradable polymer and with/without nanoclay using the compression molding process. The effects of surface treatment and nanoclay on the jute based composites were characterized by thermal, mechanical, and physical analyses. Surface treated jute fiber reinforced composites showed better performances compared to untreated fiber reinforced composites. Nanoclay infused composites showed better thermal, mechanical, and physical properties compared to conventional composites.
High pressure processing (HPP) is an emerging non-thermal food processing technology, which has the ability to preserve food in fresh condition by eliminating microbes and inactivating enzymes responsible for spoilage. HPP can be applied not only for the preservation of prawns, but also for obtaining new markets. This study was designed to understand the effect of HPP on physicochemical and microbiological properties of F. indicus during chilled storage. Application of wide range of pressures on F. indicus indicated that lower pressure treatment revealed marginal difference on physicochemical and microbiological properties compared to control; whereas, at high pressures, apparent reduction of bacteria, increase of oxidation, cooked appearance and hardness were observed. Based on these findings, a range of parameters was selected for optimizing processing condition for the treatment of F. indicus by using response surface methodology. This study established HPP as an alternative technology for improving the overall quality and shelf life of F. indicus during chilled storage.
The present book reports the design of experimental work to be executed for establishing approximate generalized empirical model for Bamboo (machining properties) processing operations such as cross cutting, external knot removal,splitting, internal knot removal, sliver and stick making, on the basis of experimentation data chosen, using methodology of engineering experimentation. The evolution of bamboo machining properties using processing cutters is a complex phenomenon. There are many factors (like geometric variables of machine and bamboo, variation in angular speed, torque and current) affecting the performance of bamboo processing machine. This book presents an experimental investigations and Sequential classical experimentation technique has been used to perform experiments for various sizes of bamboo at different varying speed. An attempt of mini-max principle has been made to optimize the range bound process parameters for minimizing processing torque, Energy, and time required for bamboo processing operations. This book also reports on design & development of machine with specialty of multiple operations of bamboo processing incorporated in a single machine.
The book contains different moisture dependent engineering properties of biological materials which affecting equipment adjustments and performance. Therefore, the effect of moisture content (m.c.) on engineering properties of agricultural materials is an important consideration for post-harvest handling and agricultural/food processing operations. Knowledge of thermal properties of agricultural materials are essential for the modeling, optimization, and design of processes and processing equipment for the operations based on thermal treatments such as dehydration, blanching, cooking, heating, cooling, steaming, frying, roasting, freezing etc. Generally, physical properties such as shape, size, volume and surface area are very important in many problems associated with the design or developing a specific machine and the analysis of material behavior during handling, transportation, drying and storage processes. The book is intended for the postgraduates and undergraduates students of Agricultural Engineering, Food Technology and allied subjects. The book should serve as useful information to the research workers, designers, and others professionals.
Nonlinear Optics (NLO) deals with the interactions of applied electromagnetic fields in various materials to generate new electromagnetic field altered in phase, frequency, amplitude or other physical properties. The nonlinear optical properties of materials play a role in many applications. The second order nonlinear response has a wide range of applications in the field of telecommunications; optical computing, storage and information processing etc. The third-order nonlinear optical response is important in all-optical switching, signal processing, and ultrafast optical communications. The objectives of the book covers synthesis and growth of bulk single crystals of organic nonlinear optical materials; Characterization of grown crystals by X-ray, thermal, mechanical and spectral techniques; Investigating the linear and nonlinear optical properties of the materials; provides a firm relationship between nonlinear optical property and molecular structure of the materials. The book consists of eight chapters. The extensive studies of the above objectives are presented in these chapters.
The book on Post Harvest Processing of Jatropha curcas outlines useful methods to describe the various agricultural processing operations such as cleaning, drying, decorticating, oil separation, etc. and the equipments for decorticator and oil expeller. The book also high lights the importance of various physical properties of oilseeds in relation to its processing and designing the equipments. The decorticator and oil expeller equipments are very useful for small and medium farmer for processing of Jatropha to get maximum oil yield.
Photonic Band Gap (PBG) materials are artificial, periodic dielectrics that enable engineering of the most fundamental properties of electromagnetic waves. Unlike traditional semiconductors that rely on the propagation of electrons through an atomic lattice, PBG materials execute their novel functions through selective trapping or “localization of light” using engineered defects within the dielectric lattice. This is of great practical importance for all-optical communications and information processing. Optical properties of photonic crystals (PCs) have been studied such as band structure, transmission and reflection spectra for 1-D, 2-D and 3-D PCs. Along with this, photonic devices are designed for applications in optical communication.
Natural fibers and their composites have a momentous history in the advancement of human civilization. The most primitive example of composite materials comprised straw and mud in the form of bricks for building constructions and the most advanced example is their use on aircrafts in highly demanding environments. The progressive dwindling of fossil fuels, radical rise in petroleum prices, and increasing consumer interest in sustainable green products- have generated considerable interest in the development of composites based on natural fibres as low cost alternatives to glass. Incorporation of natural fibres into polymer matrices can reduce the overall usage of petrochemicals, thereby decreasing the release of sequestered carbon; increasing the use of renewable materials and reducing the ecological impact of petroleum based synthetic materials. This book will be a valuable resource for composites researcher that contains a comprehensive literature review on natural fibre polymer composites and experimental work on hemp fibre treatments, processing and characterization and processing, properties and ageing on hemp/epoxy and hemp/polylactide bicomposites.
This work was designed to throw some lights on the chemical characteristics of bitter orange manufacturing wastes including flavedo layer and seeds. Therefore, both flavedo and seeds of fresh bitter orange fruits were individually separated. Chemical composition and some phytocompounds of both seeds and flavedo were estimated. Moreover, antioxidant power of flavedo extracts (water and ethanolic aqueous solutions) was determined. Physical and chemical properties of bitter orange seed oil were also studied. Defatted bitter orange seed flour was subjected to physicochemical testes including foam and whipping properties, water and oil holding capacity. In addition, possibility of utilization of dried flavedo powder and its extracts as natural antioxidant as well defatted seed flour in the field of backing process (biscuit and balady bread) were also performed. The obtained results revealed that 80% ethanolic extract had high antioxidant properties. Bitter orange seed oil had chemical and physical properties close to corn oil. Also, the seed flour could be used at 2.5% to supplement the balady bread as a plant protein without any drawback in the organoleptic properties.
Over the last decades, nutmeg processing industries facing problem of decorticating nutmegs to produce kernels for further processing. Keeping this in mind the research was undertaken at PHT scheme, University of Agricultural Sciences, Bangalore-221 005. This book entitled “Nutmeg Decorticator - Development, Optimization and Processing techniques” is providing new way of processing nutmegs. The book is divided in to six chapter viz., Introduction, Review of literature, Material and methods, Experimental results, Discussion, Summary and References. At the end, cost analysis is incorporated which contain decorticator manufacturing cost and operational cost. The book contains review of all aspect of nutmeg processing, performance of various decorticators, physical properties of various biological materials. The finding of developed decorticator has been incorporated in the book and it contain latest, reliable and usable information about nutmeg decortication and processing to the entrepreneur.
Digital signal processing (DSP) is currently the most widely used means of resolving problems in the field of information technology, automation, measurement technology, science and other fields. Digital systems have many advantages over analog systems. DSP system can be easily modified through a modification of the software. In the case of an analog system modification is necessary to change the design of the whole circuit. DSP system can be easily and accurately reproduced. The analog system is loaded with components tolerance and dependence on temperature or supply voltage. Features DSP system does not change with time, because the properties of digital components do not change with time. In our text we will focus on theoretical and practical aspects of implementation of digital filters using ATxmega16 microcontroller from Atmel.
Superconducting composites are widely used in many industrial applications especially in electrical power transmission because of their amazing properties. The achievement of optimal performances (high critical current density and appropriated mechanical properties) requires a deep knowledge of the processing parameters of silver sheathed Bi-2333 composite tapes and copper sheathed MgB2 composite wires and tapes. In the PIT method each deformation step should be understood and controlled to insure the results of the whole process. Different mechanical deformation routes are possible in the PIT method such as swaging, extrusion, drawing and rolling in various shapes. A proper understanding of the processing parameters of these mechanical deformation processes and of the initial billet conditions will pave the way for an optimised fabrication process. The relationships between processing parameters, the conductor geometry and the physical properties are being utilised in the optimisation and control of the fabrication processes.
The work presented in this book has been aimed at developing an understanding the role of pentosans in relation to the pasting properties of flours prepared from different hard wheat varieties commonly grown in Pakistan. Pasting properties are useful to predict performance of wheat flour during processing and staling of bread. It has long been speculated that variations in the type and level of pentosans may be the reason behind different processing and quality characteristics of the products made out of different wheat varieties. A better control of such characteristics would give bakers the ability to produce innovative products of a consistent quality. Therefore, a comprehensive investigation was long awaited to draw some definitive conclusions on the role of pentosans in flour pasting behavior. In this context, this study is very important as it addresses the issue in a most comprehensive manner so far using multiple dimensions. This work adds a lot of new knowledge to help understand the complex interplay between the levels and the types of pentosan (water extractable and water unextractable pentosans) on the flour pasting behavior determined by different parameters.
The primary focus of the book is to analyze defects on the finished extruded plastic product. Consequently, the emphasis throughout the book is how various stages involved in the production of the finished Product influences its properties. For example, which manufacturing process will be preferable for a given plastic? Having decided on the manufacturing process, which type of process will give optimum product properties? What is the best type of processing technique to reduce defects? How do processing conditions affect the properties of the part produced and which plastic material is most suitable for a particular application? The book addresses the elements that must be considered to come up with appropriate answers to these types of questions. The distinguishing features of the book are intended to address certain problems associated with plastic extrusion defects. This work is a practical guide, bringing together both defect and materials-processing considerations. It can be used as a reference for operators, engineers, and managers, or in educational courses.