Download or read book The Effect of Composition on the Viscosity Crystallization and Dissolution of Simple Borate Glasses and Compositional Design of Borate Based Bioactive Glasses written by Kathryn Lynn Goetschius and published by . This book was released on 2014 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Borate glasses have recently been developed for a variety of medical applications, but much less is known about their structures and properties than more common silicate glasses. Melt properties and crystallization tendency for compositions in the Na2O-CaO-B2O3 system were characterized using differential thermal analysis and viscosity measurements. Characteristic viscosity (isokom) temperatures varied with the ratio between the modifier content (Na2O+CaO) and B2O3, particularly at lower temperatures, consistent with the changes in the relative concentrations of tetrahedral borons in the glass structure. Similar glasses were used to study dissolution processes in water. These alkali-alkaline earth glasses dissolve congruently and follow linear dissolution kinetics. The dissolution rates were dependent on the glass structure, with slower rates associated with greater fractions of four-coordinated boron. For glasses with a fixed alkaline earth identity, the dissolution rates increased in the order Li
Download or read book Phosphate and Borate Bioactive Glasses written by Akiko Obata and published by Royal Society of Chemistry. This book was released on 2022-05-04 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inorganic glasses are successfully used in the biomedical field, in particular degradable glasses have found applications in tissue engineering, bone regeneration and tooth remineralisation. Silicate glasses are the most commonly used ones but phosphate and borate glasses are attracting more and more interest owing to their special properties, differing from those of silicate bio-glasses. Phosphate and borate glasses thus open up potential routes for new therapeutic applications. This book focuses on these emerging materials. Bridging the phosphate and borate glasses communities, this book provides a fundamental treatment of atomic structure and physicochemical properties before highlighting their current and potential future applications. Phosphate and borate glasses not only feature a broader range of glass formation than silicate glasses. Their ability to completely dissolve in water with the solubility varying over orders of magnitude with compositional changes, makes them exciting materials for delivering therapeutic agents into the human body. Biomaterials scientists working in glasses, hard tissue engineering and regenerative medicine will find this a must-have book to own, alongside their more traditional silicate glass tomes.
Download or read book Bioactive Glasses and Glass Ceramics written by Francesco Baino and published by John Wiley & Sons. This book was released on 2022-06-17 with total page 904 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bioactive Glasses and Glass-Ceramics Fundamentals and Applications A Comprehensive and Critical Overview of Bioactive Glasses and Glass-Ceramics Bioactive glasses and glass-ceramics are a versatile class of biocompatible materials that have an astonishing impact in biomedicine. Bioactive Glasses and Glass-Ceramics: Fundamentals and Applications presents topics on the functional properties, processing, and applications of bioactive glasses and glass-ceramics. The primary use of bioactive glasses and glass-ceramics is to repair bone and dental defects; however, their full potential is yet to be fulfilled. Many of today’s achievements in regenerative medicine and soft tissue healing were unthinkable when research began. As a result, the research involving bioactive glasses and glass-ceramics is highly stimulating and continuously progresses across many different disciplines including chemistry, materials science, bioengineering, biology, and medicine. Topics relating to these disciplines and covered within the work include: Fundamentals on bioactive glasses and glass-ceramics, bioactive glasses in today’s market, and improvements and challenges for the future Scalability and other issues when taking bioactive glass from lab to industry/commercialization applications, plus clinical challenges Trending topics such as bioactive glass porous scaffolds, additive manufacturing of bioactive glasses, and nano-engineering of bioactive glasses The various bioactive glass compositions which have been developed as medical products in an expanding range of forms and applications Bioactive Glasses and Glass-Ceramics: Fundamentals and Applications serves as a comprehensive and complete reference work on bioactive glasses and glass-ceramics for research and development (R&D) materials scientists, surgeons, and physicians, and leadership at glass and medical companies. Students and professors in fields of study pertaining to the aforementioned disciplines will also derive value from the work.
Download or read book Bioactive Glasses written by Aldo R. Boccaccini and published by Royal Society of Chemistry. This book was released on 2016-12-01 with total page 550 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of bioactive glasses has been expanding continuously over recent years. This book aims to give the material's scientist an up-to-date reference and guide for education, studies and research.
Download or read book Borate Glasses written by L. D. Pye and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 631 pages. Available in PDF, EPUB and Kindle. Book excerpt: Boron Oxide plays a key role in numerous glasses of high technological importance, yet its role in glass structure is far from clear. Indeed, in recent years there have been serious chal lenges to previous structure concepts for both crystalline and glassy borates. These challenges were sufficient to warrant a re examination of the structure of borate glasses using the most pow erful tools currently available. To provide a suitable forum for this undertaking, a four-day conference on "Boron in Glass and Glass Ceramics" was convened at Alfred University, June 3-8, 1977 to review the best scientific thinking on structure and to debate conflicting views and discuss properties and applications of borate glasses. This conference was also the first in a New University series on Glass Science to be rotated among Alfred University, The Pensyl vania State University, Rensselaer Polytechnic Institute, and the University of Missouri-Rolla. The present volume represents the proceedings of the first conference in this series. The volume begins with a review of the remarkable contribution of Jan Krogh-Moe to the understanding of the structure of Borate glasses. This review, authored by Professor N. J. Kreidl, concludes by dedicating the proceedings of this conference as a Krogh-Moe Fest schrift. The volume continues with a historical review by D. L. Griscom, originally prepared for circulation to the contributors prior to the conference. An Epilogue to the opening chapter brings the survey up-to-date in light of the conference papers.
Download or read book Borate Glasses written by Lenwood D. Pye and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Borate Glasses written by L. Ya Mazelev and published by Springer. This book was released on 2013-12-07 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Borate Glasses Crystals Melts written by Adrian C. Wright and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Sulfur on Structure and Conversion of Bioactive Borate Glasses written by Ali Mohammadkhah and published by . This book was released on 2012 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The effect of sulfur on glass structure and the conversion process of bioactive CaO-LI2O-B2O3 glasses were studied. One glass without and two glasses with different amounts of sulfur were made using conventional melting and dry quenching techniques. These glasses reacted with a phosphate solution and converted to hydroxyapatite. Particles (150-355[mu]m) were reacted in 0.25 and 0.5 molar K2HPO4 solutions at 37°C for 2 to 96 hours. The weight loss of the particles and the final pH of the solution were measured. The weight loss measurements indicated that the reaction rate increases with increasing the sulfur content. Sulfur was released from the glass, causing the pH of the solution to decrease, but was absent in the reacted layer. In the in-vivo studies, the effect of sulfur and phosphorus on the conversion of two different bioactive borate glasses was studied, in-vivo. Discs made from two sulfur-free glasses (CaLB-0 and 93B3-0) and two sulfur-containing glasses (CaLB-12 and 93B3-6) were implanted in a subcutaneous site in rats for 2, 4, and 12 weeks. Each rat remained healthy during the experiment and there were no sign of infection or necrosis at the implantation site. The CaLB glass discs reacted with the body fluids and formed a thin calcium phosphate reacted layer on their surface, but the 93B3 glass discs reacted to form a thicker calcium phosphate reacted layer with an onion-skin structure. Compared the phosphorus-free CaLB implants to phosphorus-containing 93B3 implants the CaLB implants absorbed 2 times more phosphorus from the body fluids to form the calcium phosphate reacted layer. Compared to the CaLB implants, the connective tissue attached to the 93B3 implants was ~3 times thicker, and contained more blood vessels and collagen. For all of the sulfur-containing implants sulfur released to the body fluids and was not presented in the reacted materials"--Abstract, leaf iv.
Download or read book Borate Glasses Crystals Melts written by Yanko B. Dimitriev and published by . This book was released on 2001 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bioactive Behavior of a Borate Glass written by Marina N. Richard and published by . This book was released on 2000 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: "For the past 30 years, the bioactive characteristics of special glass compositions have been demonstrated. Until now, phosphate containing soda-lime-silicate glasses such a 45S5 Bioglass®, were used to stimulate bone repair. Through the formation of an osteoconductive layer of hydroxyapatite (the main inorganic compound of bone) on the glass surface, direct bonding with bone will then occur. The rate of formation of hydroxyapatite was studied for the first silica-free borate glass of composition analogue to 45S5 and for a partially crystallized 45S5 glass. An cell-free process has been modeled to assess the formation of hydroxyapatite on the glass. The process involves the reaction of borate glass particles in phosphate solution of various molarity and starting pH. The formation of hydroxyapatite was observed best in a 0.1 Molar phosphate solution for both glasses. The reaction products have been investigated using X-ray diffraction (XRD), Infrared (IR) spectroscopy, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) and Inductively Coupled Plasma - Atomic Emission Spectrometer (ICP). The positive outcome of the model lead to further investigation of the borate glass. In vitro experiments were performed using MC3T3-E1 bone cells. The borate glass provided a marginally suitable environment for the growth of cells due to the release of boron. Successful in vivo experiments demonstrated bone growth around the borate glass particles very similar to that for the commercially used 45S5 glass. The successful bioactive response obtained with the first silica-free glass composition opens the way to the development of other compositions for bioactive use. Based on our study, future medical applications of a bioactive borate glass may dramatically reduce the rehabilitation time for patients"--Abstract, leaf iv.
Download or read book Borate Glasses Crystals Melts 7th International Conference written by Alex C. Hannon and published by . This book was released on 2014-06-30 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the Seventh International Conference on Borate Glasses, Crystals and Melts: New techniques and practical applications, Borate7, held at Dalhousie University, Halifax, Nova Scotia, Canada on 21-25 August 2011. A collected volume of papers from the Seventh International Conference, the papers were originally published in Physics and Chemistry of Glasses: European Journal of Glass Science and Technology Part B. Edited by A. C. Hannon, J. W. Zwanziger, S. Kroeker, L. Cormier & R. Youngman
Download or read book Dissolution of Borate Glasses and Precipitation of Phosphate Compounds written by Jaime Lynn George and published by . This book was released on 2015 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Borate glasses have been developed for biomedical applications such as scaffolds for soft tissue and bone repair. The dissolution processes of borate glasses in phosphate-containing aqueous solutions were studied by [mu]-Raman spectroscopy which provided information about the types and concentrations of borate species released into the solution as a function of time and characterized the formation of calcium phosphate reaction products on the glass surface. Boric acid molecules (H3BO3) and borate anions (B(OH)4−) can be detected in solution and their relative concentrations depend on the solution pH. Static and dynamic single-pass flow-through experiments were employed to study the dissolution kinetics of a borate bioactive glass 13-93B3 in water, simulated body fluid (SBF), and other solutions. As the glasses react, B-, Ca-, Na-, K-, Mg-, and P-species were released from the glass and a magnesium-containing amorphous calcium phosphate (ACP) or hydroxyapatite (HAP) layer formed on the surface of the glass. The formation of crystalline hydroxyapatite was favored with faster flow rates, longer reaction times, and increased phosphate concentration in solution. Under static conditions, the dissolution rates are initially described by a reaction-controlled model (linear kinetics), but after the glass is ~25-30% reacted, a diffusion-controlled model (parabolic kinetics) better describes the dissolution rates. The change in reaction mechanism is attributed to the diffusion of species from the glass through the ACP layer. The activation energy for the reaction-controlled process is 41.1±0.6 kJ/mol, whereas the activation energy for the diffusion process is 32.3±0.1 kJ/mol. For the SPFT experiments, glasses dissolved faster under faster flow rates and smaller glass volumes. The ion release rate was calculated and found to range from 1.7x10−5 g/m2/s for slow flow rates to 1.1x10−3 g/m2/s for lower glass volumes."--Abstract, page iv.
Download or read book Highly Reactive Silver Doped Sol gel derived Borate Glasses for Wound Healing Applications written by Shiva Naseri and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Bioactive and soluble glasses exhibit great potential in biomedical applications in both hard and soft tissue engineering. The rate at which these glasses generate a response, or their reactivity, is an important parameter for healing efficacy. Owing to their tetrahedral coordination, silicate-based glasses exhibit slow and incomplete solubility, which limit their application in soft tissue repair. Therefore, there is great interest in developing more soluble and reactive bioactive glass formulations based on the borate network forming oxide, which can be both trigonally and tetrahedrally coordinated. It has been shown that borate-based glasses have higher reactivity than silicate-based glasses attributed to their glass network structure. Limitations in conventional methods such as the lack of accuracy and time-consumption to examine reactivity/bioactivity and surface properties of bioactive and soluble glasses have led to an increased interest in finding and investigating new techniques, such as dynamic vapour sorption (DVS) and inverse gas chromatography (IGC). It was demonstrated that DVS has the ability to measure and predict the bioactivity/reactivity of silicate-, phosphate- and borate- based glasses with various specific surface areas/particle sizes or formulations. It was shown that DVS was able to measure and correlate the vapour isotherm values of melt-quench derived Bioglass® 45S5: (46.1)SiO2-(26.9)CaO-(24.4)Na2O-(2.6)P2O5 (mol %) of three different particle sizes (surface areas) with the reactivity, bioactivity and ions release rates of glasses. Higher surface area led to the higher vapour sorption and reactivity. Additionally, IGC was utilized to examine the surface properties of melt-quench derived phosphate glasses (PGs) doped with both SiO2 and TiO2 (50P2O5-40CaO-xSiO2-(10 − x) TiO2, where x = 7, 5, 3, and 0 mol%). It was shown that IGC was more accurate and sensitive than other conventional techniques such as contact angle measurement in determining the effect of silica content on the surface properties of PGs. In conclusion, this dissertation has assessed the potential complementarity of DVS and IGC in the characterization of aqueous reactivity and surface properties of bioactive and soluble glasses.Moreover, complications in the healing of chronic wounds in patients who are at constant risk of infections have led to a great demand for the development of biomaterial based wound dressing replacement. Borate-based glasses have recently been approved for wound repair which are melt-quench derived, yet borate glasses fabricated through the sol-gel process have the benefits of higher dissolution rate, which could potentially lead to the more rapid wound repair. However, the potential of sol-gel derived borate glasses, in particular, silver doped borate-based glasses (AgBGs) for soft tissue repair has so far not been investigated. In this thesis, anti-bacterial AgBGs in the B2O3Ag2O-CaO-P2O5 system were fabricated through optimization of sol-gel process and glass composition. Silver ion release rate and anti-bacterial activity were correlated and demonstrated dose dependent efficacy against Escherichia coli or Staphylococcus aureus and Pseudomonas aeruginosa bacteria. In addition, AgBGs were systematically examined to determine their effects on cellular functions such as metabolic activity, cell viability and migration through in vitro cell culture of human derived keratinocyte (HaCat) and mouse derived fibroblastic (NIH/3T3) cell lines. It was verified that silver release from AgBGs was not toxic to both cells at lower concentrations (
Download or read book Introduction to Glass Science and Technology written by James E Shelby and published by Royal Society of Chemistry. This book was released on 2015-11-06 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a concise and inexpensive introduction for an undergraduate course in glass science and technology. The level of the book has deliberately been maintained at the introductory level to avoid confusion of the student by inclusion of more advanced material, and is unique in that its text is limited to the amount suitable for a one term course for students in materials science, ceramics or inorganic chemistry. The contents cover the fundamental topics of importance in glass science and technology, including glass formation, crystallization, phase separation and structure of glasses. Additional chapters discuss the most important properties of glasses, including discussion of physical, optical, electrical, chemical and mechanical properties. A final chapter provides an introduction to a number of methods used to form technical glasses, including glass sheet, bottles, insulation fibre, optical fibres and other common commercial products. In addition, the book contains discussion of the effects of phase separation and crystallization on the properties of glasses, which is neglected in other texts. Although intended primarily as a textbook, Introduction to Glass Science and Technology will also be invaluable to the engineer or scientist who desires more knowledge regarding the formation, properties and production of glass.
Download or read book Effect of Dissolved Water on Physical Properties of Silver Borate Glasses written by E. Richard Reynolds and published by . This book was released on 1974 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Structure of Boron Oxide and Alkali Borate Glasses written by Jan Krogh-Moe and published by . This book was released on 1959 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
