Download or read book Deuterium Nuclear Magnetic Resonance NMR and Rheology of Microgel Colloids at Ambient and High Pressure written by Suhad Adnan Sbeih and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Microgel colloids exhibit a polymer collapse transition resulting in a large reduction in colloid particle volume at high temperatures or pressures. They are of interest because of their potential for applications in areas, like drug delivery and chemical separation, that involve the uptake, encapsulation and release of small or biological molecules. The goal of this work is to obtain a microscopic understanding of the internal structure and microscopic dynamics of microgels by examining the temperature and pressure dependence of the collapse transition. Deuterium NMR (2H NMR) has been used to probe the microscopic dynamics of crosslinked poly N-isopropylacrylamide (polynipam) chains, in microgel colloids, as a function of temperature and pressure for a series of four crosslink densities (Cd). Each crosslinked microgel colloids was synthesized with deuteron labels on the nipam backbone (d3 nipam). Macroscopic properties of unlabeled colloids having the same crosslink densities were characterized by dynamic light scattering (DLS) and rheology. Rheological characterization as a function of temperature (T) and particle concentration (C), and for 4 crosslink densities, showed that the microgel viscosity decreases as temperature is increased. The Krieger- Dougherty model of the relative viscosity as a function of volume fraction was employed for viscosity analysis. The measured viscosity in the colloidal regime (at high T, low C) collapsed onto one line when plotted against volume fraction. This yields a measure of the water content in the particles as function of T. The water volume fraction in the microgel particle at 45OC was always found to be 0.6 for any Cd. 2H NMR spectra of the d3 nipam suspensions for all Cd indicated freely moving chains at low temperature and a nearly immobilized fraction above 35OC. This is consistent with DLS observations of a transition from swollen to collapsed colloids. Nipam segments in the collapsed phase of the d3 nipam suspension were more mobile than those in the dry powder. This suggests significant amounts of water in the collapsed phase, a finding consistent with the rheology observations. Variable pressure NMR (up to 90 MPa) showed a slight increase in transition temperature with pressure for all Cd values studied.
Download or read book NMR and MRI of Gels written by Yves De Deene and published by Royal Society of Chemistry. This book was released on 2020-07-07 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gels are used in a large variety of commercial and scientific products from drug delivery systems and food science to biomedical sensors. They also are invaluable in MRI physics research where they mimic biological tissue and in radiotherapy quality assurance where they are used to capture the three dimensional radiation dose distribution. This unique book discusses the state-of-the-art of NMR and MRI techniques in studying the physics and chemistry of gel systems, in their application as MRI phantoms and as three dimensional radiation dosimeters. The first part of the book will cover the fundamental physical concepts of gels and the NMR techniques to study gel systems. The second part is dedicated to the application of gels in the life sciences and in the medical practice to validate radiotherapy and new MRI techniques. Filling the gap in literature, this volume provides the scientific reader with an extensive overview of possible techniques and methods to study the interesting properties and applications of gels. For the MRI researcher and medical physicist, the book will be a valuable resource in using gel phantoms for validating contemporary MRI techniques and radiotherapy treatments.
Download or read book Dynamics of Soft Matter written by VICTORIA GARCIA SAKAI and published by Springer Science & Business Media. This book was released on 2011-12-19 with total page 455 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamics of Soft Matter: Neutron Applications provides an overview of neutron scattering techniques that measure temporal and spatial correlations simultaneously, at the microscopic and/or mesoscopic scale. These techniques offer answers to new questions arising at the interface of physics, chemistry, and biology. Knowledge of the dynamics at these levels is crucial to understanding the soft matter field, which includes colloids, polymers, membranes, biological macromolecules, foams, emulsions towards biological & biomimetic systems, and phenomena involving wetting, friction, adhesion, or microfluidics. Emphasizing the complementarities of scattering techniques with other spectroscopic ones, this volume also highlights the potential gain in combining techniques such as rheology, NMR, light scattering, dielectric spectroscopy, as well as synchrotron radiation experiments. Key areas covered include polymer science, biological materials, complex fluids and surface science.
Download or read book Viscoelastic Behavior of Rubbery Materials written by C. Michael Roland and published by OUP Oxford. This book was released on 2011-06-30 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: The enormous size of polymer molecules causes their molecular motions to span a broad range of length scales and give rise to viscoelastic behaviour. This rate-dependence of the properties is a predominant characteristic of soft materials (rubbers, biopolymers, lubricants, adhesives, etc.). Improving the performance and developing new applications for soft materials require an understanding of the basic principles of how molecular motions underlie physical properties. This text is intended to provide grounding in fundamental aspects of the dynamic behavior of rubbery materials, adopting a molecular perspective in its treatment to emphasize how microscopic processes are connected to the observed macroscopic behavior. The latest discoveries and advances in the science and technology of rubbery materials are described and critically analyzed.
Download or read book Stimuli Responsive Dewetting Wetting Smart Surfaces and Interfaces written by Atsushi Hozumi and published by Springer. This book was released on 2018-11-16 with total page 467 pages. Available in PDF, EPUB and Kindle. Book excerpt: Superhydrophobic surfaces, artificially mimicking lotus leaves, have captured the attention of scientists and engineers over the past few decades. Recent trends have shifted from superhydrophobicity to superominipohobicity, or superamphiphobicity. In addition, dynamic rather than static surface wetting/dewetting properties, which can be triggered by various stimuli, including temperature, pH, magnetic/electric fields, solvents, light exposure etc, have been highly sought after for commercial applications. This book will focus on recent topics related to various stimuli-responsive wetting/dewetting surfaces, and give an overview of the knowledge and concepts of how to design and establish these smart artificial surfaces, which can be used for technical developments in a wide variety research fields.
Download or read book Simulation Methods for Polymers written by Michael Kotelyanskii and published by CRC Press. This book was released on 2004-03-01 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Glass Transition written by E. Donth and published by Springer Science & Business Media. This book was released on 2013-04-17 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes and interrelates the following processes: cooperative alpha processes in a cold liquid, structural relaxation in the glass near Tg, the Johari-Goldstein beta process, the Williams-Götze process in a warm liquid, fast nonactivated cage rattling and boson peak, and ultraslow Fischer modes.
Download or read book Program and abstracts book written by and published by . This book was released on 2001 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Science and Technology of Rubber written by James E. Mark and published by Elsevier. This book was released on 2011-07-28 with total page 762 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Science and Technology of Rubber, Third Edition provides a broad survey of elastomers with special emphasis on materials with a rubber-like elasticity. As in the 2nd edition, the emphasis remains on a unified treatment of the material; exploring topics from the chemical aspects such as elastomer synthesis and curing, through recent theoretical developments and characterization of equilibrium and dynamic properties, to the final applications of rubber, including tire engineering and manufacturing. Many advances have been made in polymer and elastomers research over the past ten years since the 2nd edition was published. Updated material stresses the continuous relationship between the ongoing research in synthesis, physics, structure and mechanics of rubber technology and industrial applications. Special attention is paid to recent advances in rubber-like elasticity theory and new processing techniques for elastomers. This new edition is comprised of 20% new material, including a new chapter on environmental issues and tire recycling.
Download or read book Handbook of Elastomers Second Edition written by Anil K. Bhowmick and published by CRC Press. This book was released on 2000-11-02 with total page 954 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Provides the latest authoritative research on the developments, technology, and applications of rubbery materials. Presents structures, manufacturing techniques, and processing details for natural and synthetic rubbers, rubber-blends, rubber composites, and thermoplastic elastomers. 80% revised and rewritten material covers major advances since publication of the previous edition."
Download or read book Self Assembling Systems written by Li-Tang Yan and published by John Wiley & Sons. This book was released on 2016-12-19 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides comprehensive knowledge on concepts, theoretical methods and state-of-the-art computational techniques for the simulation of self-assembling systems Looks at the field of self-assembly from a theoretical perspective Highlights the importance of theoretical studies and tailored computer simulations to support the design of new self-assembling materials with useful properties Divided into three parts covering the basic principles of self-assembly, methodology, and emerging topics
Download or read book Principles of Polymer Science and Technology in Cosmetics and Personal Care written by E. Desmond Goddard and published by CRC Press. This book was released on 1999-03-10 with total page 688 pages. Available in PDF, EPUB and Kindle. Book excerpt: This valuable reference bridges the widening gap between the knowledge about the use of polymers in the cosmetics industry and the greater understanding of polymeric behaviour necessary for continuing research and development. Providing both a solid grounding in polymer science for novices to the field and fresh insights for experienced researchers, 'Principles of Polymer Science and Technology in Cosmetics and Personal Care' introduces fundamentals of polymers, including their classification, molecular weight definitions, thermodynamics, rheology and properties in the solid and semi-solid state.
Download or read book Nontraditional Careers for Chemists written by Lisa M. Balbes and published by . This book was released on 2007 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Chemistry background prepares you for much more than just a laboratory career. The broad science education, analytical thinking, research methods, and other skills learned are of value to a wide variety of types of employers, and essential for a plethora of types of positions. Those who are interested in chemistry tend to have some similar personality traits and characteristics. By understanding your own personal values and interests, you can make informed decisions about what career paths to explore, and identify positions that match your needs. By expanding your options for not only what you will do, but also the environment in which you will do it, you can vastly increase the available employment opportunities, and increase the likelihood of finding enjoyable and lucrative employment. Each chapter in this book provides background information on a nontraditional field, including typical tasks, education or training requirements, and personal characteristics that make for a successful career in that field. Each chapter also contains detailed profiles of several chemists working in that field. The reader gets a true sense of what these people do on a daily basis, what in their background prepared them to move into this field, and what skills, personality, and knowledge are required to make a success of a career in this new field. Advice for people interested in moving into the field, and predictions for the future of that career, are also included from each person profiled. Career fields profiled include communication, chemical information, patents, sales and marketing, business development, regulatory affairs, public policy, safety, human resources, computers, and several others. Taken together, the career descriptions and real case histories provide a complete picture of each nontraditional career path, as well as valuable advice about how career transitions can be planned and successfully achieved by any chemist.
Download or read book Advances in Food Biochemistry written by Fatih Yildiz and published by CRC Press. This book was released on 2009-12-16 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the biochemistry of food is basic to all other research and development in the fields of food science, technology, and nutrition, and the past decade has seen accelerated progress in these areas. Advances in Food Biochemistry provides a unified exploration of foods from a biochemical perspective. Featuring illustrations to elucidate m
Download or read book Thermoreversible Networks written by Klaas te Nijenhuis and published by Springer. This book was released on 2014-03-12 with total page 267 pages. Available in PDF, EPUB and Kindle. Book excerpt: This review shows that the measurement of viscoelastic properties is a powerful tool in the study of thermoreversible gels. Although many conclusions may be drawn about network development and its structure, it is also shown that the use of additional techniques (e.g. small angle S-ray and neutron scattering techniques and optical rotation) and the combination with thermodynamics and network models, widens the insight in the crosslinking process and the gel structure temendously. A general Introduction is followed by eight Chapters concerning synthetic polymers (PVC, PVAL, PMMA, PS, PAN, PE, ABA blockcopolymers and LCP's) and four Chapters concerning biopolymers (gelatin, agarose, carrageenans and gellan gum).
Download or read book Phase Transitions in Liquid Crystals written by Arthur N. Chester and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Nato Advanced Study Institute "Phase Transitions in Liquid Crystals" was held May 2-12, 1991, in Erice, Sicily. This was the 16th conference organized by the International School of Quantum Electronics, under the auspices of the "Ettore Majorana" Centre for Scientific Culture. The subject of "Liquid Crystals" has made amazing progress since the last ISQE Course on this subject in 1985. The present Proceedings give a tutorial introduction to today's most important areas, as well as a review of current results by leading researchers. We have brought together some of the world's acknowledged experts in the field to summarize both the present state of their research and its background. Most of the lecturers attended all the lectures and devoted their spare hours to stimulating discussions. We would like to thank them all for their admirable contributions. The Institute also took advantage of a very active audience; most of the students were active researchers in the field and contributed with discussions and seminars. Some of these student seminars are also included in these Proceedings. We did not modify the original manuscripts in editing this book, but we did group them according to the following topics: 1) "Theoretical Foundations"; 2) "Thermotropic Liquid Crystals"; 3) "Ferroelectric Liquid Crystals"; 4) "Polymeric Liquid Crystals"; and 5) "Lyotropic Liquid Crystals".
Download or read book Oral Delivery of Insulin written by T.A. Sonia and published by Elsevier. This book was released on 2014-12-11 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diabetes Mellitus, a syndrome of disordered metabolism, characterised by abnormal elevation in blood glucose level, has become a life-threatening condition for many people. Current means of therapy for Diabetes Mellitus do not mimic the normal physiological pattern of insulin release. Oral delivery is the preferred route of administration due to its non-invasive nature. Oral delivery of insulin presents an overview of Diabetes Mellitus, and discusses the strategies and techniques adopted for oral delivery of insulin. This title begins with an introductory chapter on symptoms, complications and therapy for Diabetes Mellitus. Subsequent chapters cover the various routes for administering insulin; the challenges and strategies of oral delivery; experimental techniques in the development of an oral insulin carrier; lipids; inorganic nanoparticles and polymers in oral insulin delivery; and a summary and presentation of future perspectives on oral delivery of insulin. - Presents an overview of Diabetes Mellitus - Includes a discussion of various strategies and techniques adopted for oral delivery of insulin - Presents an update of research in the field
