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پزشکی، دندانپزشکی و داروسازی
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محصولات
Adventures in Engineering for Kids: 35 Challenges to Design the Future - Journey to City X - Without Limits, What Can Kids Create? - Orginal Pdf
نویسندگان: خلاصه: Adventures in Engineering for Kids: 35 Challenges to Design the Future - Journey to City X - Without Limits, What Can Kids Create? Brett Schilke
Water-Soluble Polymers : Solution Properties and Applications - Original PDF
نویسندگان: خلاصه: This volume contains a series of papers originally presented at the symposium on Water Soluble Polymers: Solution Properties and Applications, sponsored by the Division of Colloids and Surface Chemistry of the American Chemical Society. The symposium took place in Las Vegas City, Nevada on 9 to 11th September, 1997 at the 214th American Chemical Society National Meeting. Recognized experts in their respective fields were invited to speak. There was a strong attendance from academia, government, and industrial research centers. The purpose of the symposium was to present and discuss recent developments in the solution properties of water soluble polymers and their applications in aqueous systems
Structured Fluids: Polymers, Colloids, Surfactants - Original PDF
نویسندگان: خلاصه: Over the last thirty years, the study of liquids containing polymers, surfactants, or colloidal particles has developed from a loose assembly of facts into a coherent discipline with substantial predictive power. These liquids expand our conception of what condensed matter can do. Such structured-fluid phenomena dominate the physical environment within living cells. This book teaches how to think of these fluids from a unified point of view showing the far-reaching effects of thermal fluctuations in producing forces and motions. Keeping mathematics to a minimum, the book seeks the simplest explanations that account for the distinctive scaling properties of these fluids. An example is the growth of viscosity of a polymer solution as the cube of the molecular weight of the constituent polymers. Another is the hydrodynamic radius of a colloidal aggregate, which remains comparable to its geometrical radius even though the density of particles in the aggregate becomes arbitrarily small. The book aims for a simplicity, unity and depth not found in previous treatments, and includes numerous figures, tables and problems. It will be an ideal textbook for teaching undergraduates in physical science how to understand soft matter, but will also be of interest to industrial scientists, who want to gain a broader understanding of soft matter systems
Laser Application of Polymers - Original PDF
نویسندگان: خلاصه: Abstract Laser ablation of polymers has been studied with designed materials to evaluate the mechanism of ablation and the role of photochemically active groups on the ablation process, and to test possible applications of laser ablation and designed polymers. The incorporation of photochemically active groups lowers the threshold of ablation and allows high-quality structuring without contamination and modification of the remaining surface. The decomposition of the active chromophore takes place during the excitation pulse of the laser and gaseous products are ejected with supersonic velocity. Time-of-flight mass spectrometry reveals that a metastable species is among the products, suggesting that excited electronic states are involved in the ablation process. Experiments with a reference material, i.e., polyimide, for which a photothermal ablation mechanism has been suggested, exhibited pronounced differences. These results strongly suggest that, in case of designed polymers which contain photochemically active groups, a photochemical part in the ablation mechanism cannot be neglected. Various potential applications for laser ablation and the special photopolymers were evaluated and it became clear that the potential of laser ablation and specially designed material is in the field of microstructuring. Laser ablation can be used to fabricate three-dimensional elements, e.g., microoptical elements
Alkylene Oxides and Their Polymers - Original PDF
نویسندگان: خلاصه: The poly(alkylene oxide)s are linear or branched-chain polymers that contain ether linkages in their main polymer chain structure and are derived from monomers that are vicinal cyclic oxides, or epoxides, of aliphatic olefins, principally ethylene and propylene and, to a much lesser extent, butylene. These polyethers are commercially produced over a range of molecular weights from a few hundred to several million for use as functional materials and as intermediates. Lower polymers are liquids, increasing in viscosity with molecular weight. The high polymers can be thermoplastic. Solubilities range from hydrophilic water-soluble polymers that are principally derived from ethylene oxide, to hydrophobic, oil-soluble polymers of propylene oxide and butylene oxide. A wide variety of copolymers is produced, both random copolymers and block copolymers. The latter may be used for their surface-active characteristics.
Absorbable biodegradable polymers - Original PDF
نویسندگان: خلاصه: Egyptians sutured wounds as early as 3500 B.C. using a variety of natural polymers including treated intestines, which are the early versions of collagen-based surgical gut sutures.1 Synthetic, absorbable polyesters based on 2-hydroxyacetic acids were developed for preparing less tissue reactive alternatives to surgical gut sutures in the early 1970s. In addition to collagenbased polymers, other natural, absorbable polymers, such as albumin, chitosan, and hyaluronic acid and derivatives thereof have been used for many pharmaceutical and biomedical applications for several decades.2 Of these polymers, the application of chitosan and hyaluronic acid–based polymers has received a great deal of attention in the past 15 years for use in controlled drug delivery systems, tissue repair, tissue engineering, and controlling certain biological events.
Polymers in Electronics Market Report - Original PDF
نویسندگان: خلاصه: Designers of electrical and electronic components have a wide choice of polymers at their disposal - cost is a prime consideration but competition in the market place is imposing ever more stringent specification criteria on the equipment designer who, in turn, is demanding significantly improved performance from his polymer supplier. This report lists the most commonly used polymers with brief notes on their properties. This report seeks to provide an overall picture of the varied use of polymers in the manufacture of electronic components. It has endeavoured to identify trends and future movements of the market. The pattern of polymer usage has changed and material formulations have had to be modified to conform with new European Union (EU) legislation relating to the use of hazardous materials in components. Furthermore there is now far more emphasis on recycling rather than landfill disposal and these are issues covered in the report. This report will be of interest to all those involved in using polymers to produce electronic components and to those who provide the raw materials for the production.
Coatings Of Polymers And Plastics - Original PDF
نویسندگان: خلاصه: Human development is clearly linked to continuous improvements in the materials used every day. Entire stages of history have been named after the critical materials—Stone Age, Bronze Age, Iron Age, and now, the Age of Plastics. When asked his opinion on chemistry’s largest contribution to science and society, Lord Todd, the President of the Royal Society of London, responded: “I am inclined to think that the development of polymerization is, perhaps, the biggest thing chemistry has done, where it has had the biggest effect on everyday life. The world would be a totally different place without artificial fibers, plastics, elastomers,آیا کتاب مورد نظر هنوز بر روی سایت قرار نگرفته است؟ جای نگرانی نیست! کافی است بر روی گزینه سفارش کتاب کلیک کرده و درخواست خود را ثبت کنید. در کمتر از چند ساعت کتاب شما را آماده خواهیم کرد.