In this chapter, we will restrict our attention to the ferrites and a few other closely related materials. The great interest in ferrites stems from their unique combination of a spontaneous magnetization and a high electrical resistivity. The observed magnetization results from the difference in the magnetizations of two non-equivalent sub-lattices of the magnetic ions in the crystal structure. Materials of this type should strictly be designated as “ferrimagnetic” and in some respects are more closely related to anti-ferromagnetic substances than they are to ferromagnetics in which the magnetization results from the parallel alignment of all the magnetic moments present. We shall not adhere to this special nomenclature except to emphasize effects, which are due to the existence of the sub-lattices.

Ferromagnetic materials

There is a special reason for reviewing this book at this time: it is the 50th edition of a compendium that is known and used frequently in most chemical and physical laboratories in many parts of the world. Surely, a publication that has been published for 56 years, withstanding the vagaries of science in this century, must have had something to offer. There is another reason: while the book is a standard fixture in most chemical and physical laboratories, including those in medical centers, it is not as frequently seen in the laboratories of physician's offices (those either in solo or group practice). I believe that the Handbook can be useful in those laboratories. One of the reasons, among others, is that the various basic items of information it offers may be helpful in new tests, either physical or chemical, which are continuously being published. The basic information may relate

Handbook of Chemistry and Physics

Electrospinning is a versatile and viable technique for generating ultrathin fibers. Remarkable progress has been made with regard to the development of electrospinning methods and engineering of electrospun nanofibers to suit or enable various applications. We aim to provide a comprehensive overview of electrospinning, including the principle, methods, materials, and applications. We begin with a brief introduction to the early history of electrospinning, followed by discussion of its principle and typical apparatus. We then discuss its renaissance over the past two decades as a powerful technology for the production of nanofibers with diversified compositions, structures, and properties. Afterward, we discuss the applications of electrospun nanofibers, including their use as "smart" mats, filtration membranes, catalytic supports, energy harvesting/conversion/storage components, and photonic and electronic devices, as well as biomedical scaffolds. We highlight the most relevant and recent advances related to the applications of electrospun nanofibers by focusing on the most representative examples. We also offer perspectives on the challenges, opportunities, and new directions for future development. At the end, we discuss approaches to the scale-up production of electrospun nanofibers and briefly discuss various types of commercial products based on electrospun nanofibers that have found widespread use in our everyday life.

Electrospinning and Electrospun Nanofibers: Methods, Materials, and Applications

In this article, several applications of nanomaterials in food packaging and food safety are reviewed, including: polymer/clay nanocomposites as high barrier packaging materials, silver nanoparticles as potent antimicrobial agents, and nanosensors and nanomaterial-based assays for the detection of food-relevant analytes (gasses, small organic molecules and food-borne pathogens). In addition to covering the technical aspects of these topics, the current commercial status and understanding of health implications of these technologies are also discussed. These applications were chosen because they do not involve direct addition of nanoparticles to consumed foods, and thus are more likely to be marketed to the public in the short term.

Applications of nanotechnology in food packaging and food safety: Barrier materials, antimicrobials and sensors

Polymer nanoparticles: Preparation techniques and size-control parameters

Extraction of pure natural hydroxyapatite from the bovine bones bio waste by three different methods

In the present study, cobalt(II) oxide (CoO), which is hard to synthesize because of the chemical activity of cobalt metal, and the popular cobalt(II, III) oxide (Co3O4) have been successfully produced in smooth and continuous nanofibrous form by using the electrospinning technique. An aqueous cobalt acetate tetrahydrate and poly(vinyl alcohol) mixture has been electrospun and vacuously dried at 80 °C. Pure, smooth and solid Co3O4 nanofibers were produced when the dried nanofiber mats were calcined in air atmosphere at 700 °C. Water gas has been prepared by a novel technique to produce pure CoO nanofibers from the original cobalt acetate/poly(vinyl alcohol) nanofiber mats. The nanofiber mats have been hydrothermally treated in the presence of carbon at 300 °C in an especially designed reactor. The invoked physiochemical analyses have affirmed formation of both oxides in nanofibrous shape. The optical properties of the obtained nanofibers have been studied. UV−visible absorbance spectra have indicated that...

Synthesis and Optical Properties of Two Cobalt Oxides (CoO and Co3O4) Nanofibers Produced by Electrospinning Process

Spider-net within the N6, PVA and PU electrospun nanofiber mats using salt addition: Novel strategy in the electrospinning process

An introduction to fiber structure Principles of interferometry Two-beam interferometry applied to fibrous materials Multiple-beam interferometry applied to fibrous materials Interferometric determination of fiber surface topography The effect of irradiation on the optical properties of fibers Interference microscopes Back-scattering of light waves from fibers Automatic analysis of interferograms References Author index Subject index

Nasser A.M. Barakat

Papers

Extraction of pure natural hydroxyapatite from the bovine bones bio waste by three different methods

Synthesis and Optical Properties of Two Cobalt Oxides (CoO and Co3O4) Nanofibers Produced by Electrospinning Process

Spider-net within the N6, PVA and PU electrospun nanofiber mats using salt addition: Novel strategy in the electrospinning process

Interferometry of fibrous materials

Effective and reusable oil/water separation membranes based on modified polysulfone electrospun nanofiber mats