Химия
Различные книги в жанре Химия
Concise Handbook of Fluorocarbon Gases
This book describes fluorocarbons gases’ preparation process, properties, applications and their evolution over time. The impact of fluorocarbons on the ozone layer and global and the development to mitigate those effects have been specially emphasized. The first major industrial fluorinated compound was developed in the 1920’s, to replace ammonia and sulfur dioxide refrigerants, at the General Motors Frigidaire Division by Thomas Midgley, Jr. and Albert Leon Henne. They developed a family of fluorocarbons trademarked Freon® for auto air conditioning units revolutionizing the auto industry. Other applications were developed over time including fire extinguishers, propellants, blowing agents, cleaners, anesthesia, artificial blood and others impacting every facet of life. In spite of being in broad global use for nearly a century, fluorocarbon gases have gone through great evolution during the last few decades. In the 1980s it was discovered chlorofluorocarbon (CFC) gases are harmful to the ozone layer, mainly because of their chlorine content. Chlorine was released in the upper atmosphere when chlorofluorocarbon molecules were broken down by the high energy cosmic radiation. CFCs were progressively banned following the Montreal Protocol of 1987. CFCs were replaced by fluorinated gases containing either less chlorine (hydrofluoro-chlorocarbons, or HCFCs), which are much less damaging (about 90% less) to the ozone layer or with fluorinated gases containing no chlorine, i.e. hydrofluorocarbons or HFCs. HFC have no impact on the ozone layer but impact global warming detrimentally. HFCs are usable without need for changes to the existing refrigeration or air conditioning installations. More recently hydrofluoroolefins (HFOs), which have little or no negative impact on global warming, have been developed to replace or reduce the use of HFCs. HFOs are used as single compounds or in blends. Research and development continues to develop and replace the HCFCs and HFCs completely with environmentally friendly products. Concise Handbook of Fluorocarbon Gases presents a reference and text for the commercial fluorocarbon gases which have great many application in a wide range of industries such as refrigeration and air conditioning, as well as consumer products.
Supramolecular Polymers and Assemblies
Explore modern characterization methods and new applications in this modern overview of supramolecular polymer chemistry Supramolecular Polymers and Assemblies: From Synthesis to Properties and Applications delivers a superlative summary and description of general concepts and definitions in the field. The book offers informative and accessible treatments of crucial concepts like metal-containing compounds, hydrogen bonding, ionic interactions, pi-pi stacking, and more. Characterization remains a primary focus of the book throughout, making it extremely useful for practitioners in the field. Emphasis is also placed on metallo-supramolecular polymers and materials which have found applications in areas like smart or intelligent materials and systems with special photochemical and photophysical properties, like LEDs and solar cells. Applications, including self-healing materials, opto-electronics, sensing, and catalysis are all discussed as well. The book details many of the exciting developments in the field of supramolecular chemistry that have occurred since the 1987 Nobel Prize was awarded to pioneers in this rapidly developing field. Readers will also benefit from the inclusion of: A thorough introduction to supramolecular assemblies based on ionic interactions Explorations of supramolecular polymers based on hydrogen-bonding interactions, metal-to-ligand interactions, p-Electronic interactions, crown-ether recognition, cucurbiturils, and host-guest chemistry of calixarenes A discussion of cyclodextrins in the field of supramolecular polymers Examinations of supramolecular polymers based on the host-guest chemistry of pillarenes, and those formed by orthogonal non-covalent interactions A treatment of the characterization of supramolecular polymers Supramolecular Polymers and Assemblies: From Synthesis to Properties and Applications will earn a place in the libraries of researchers and practitioners of the material science, as well as polymer chemists seeding a one-stop reference for supramolecular polymers.
