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SSRN 2023年

作者： Oliveira, Jéssica Fernanda Ribeiro de Oliveira Filho, Ulisses Aparecido Rocha, Ana Julia Silva dos Santos, Hericles Campos Barreto, Ledjane Silva dos Santos, Euler Araujo Graduation Program of Material Science and Engineering Federal University of Sergipe SE São Cristóvão49100-000 Brazil

The inherent mineralization of hydroxyapatite during the synthesis of sol-gel-derived bioactive glasses has been frequently reported in the literature. To date, there is no consensus on how this mineralization occurs and how it can affect the subsequent biological behavior of the glass. In this research, we explored how the time at which the calcium precursor is added to a sol-gel synthesis affects this initial mineralization process and the consequent bioactivity and protein adsorption. It was demonstrated that late addition of the calcium nitrate (after alkoxide hydrolysis) produced a heterogeneous microstructure in which Ca2+-rich regions (nanocrystalline hydroxyapatite) formed among a less polymerized and more reactive silica network. This devitrification-like process during the synthesis resulted in increasing bioactivity and albumin adsorption. Therefore, the bioactivity of a 58S glass and its protein adsorption capacity can be modulated by choosing the moment at which calcium nitrate is added relative to the other alkoxide precursors in a sol-gel synthesis. © 2023, The Authors. All rights reserved.

关键词： Bioactivity

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FLAMMABILITY AND TOXICITY OF COMPOSITE-materialS FOR MARINE VEHICLES

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NAVAL ENGINEERS JOURNAL 1990年第5期102卷 45-54页

作者： SEVART, JL GRIFFIN, OH GURDAL, Z WARNER, GA Jeffrey L. Sevart:is a native of Kansas and a 1985 graduate of Kansas State University with a B.S. in mechanical engineering (magna cum laude). After working as a stress analysis engineer at Boeing Military Airplane Company in Wichita Kans. he attended Virginia Polytechnic Institute and State University and received an M.S. in engineering mechanics in February 1988. He currently resides in Akron Ohio working as a research engineer in tire composites research at The Goodyear Tire and Rubber Company. O. Hayden Griffin Jr.:received his B.S. and M.S. in mechanical engineering from Texas Tech University in 1970 and 1971 respectively. He received his Ph.D. in engineering mechanics from Virginia Polytechnic Institute and State University in 1980. Prior to joining the faculty of Virginia Polytechnic Institute and State University as associate professor of engineering science and mechanics in September 1985 he was employed at the U.S. Naval Surface Warfare Center (Dahlgren Virginia) BF Goodrich Tire Group (Akron Ohio) the Bendix Advanced Technology Center (Columbia Maryland) and the Johns Hopkins University Applied Physics Laboratory (Laurel Maryland). He is currently an associate director of the Virginia Institute for Material Systems. He is a registered professional engineer in Virginia and is a member of the American Society of Mechanical Engineers and the American Society for Composites. Zafer Gürdal:received his M.S. in mechanical and aerospace engineering from Illinois Institute of Technology in 1981 and his Ph.D. in aerospace engineering from Virginia Polytechnic Institute and State University in 1985. He worked as a research associate in the Aerospace and Ocean Engineering Department at Virginia Tech before joining the Engineering Science and Mechanics Department as an assistant professor in September 1985. Professor Gürdal's research interests include: composite structures failure mechanics of composites structural optimization and damage tolerant design. He is a member of the American Institute

Characteristics of both thermoplastic and thermoset composite materials as they pertain to marine vehicle applications are discussed. Comparison of various material selection factors such as strength, damage and moisture resistance, and flammability and toxicity as well as cost and availability of thermoset and thermoplastic composite materials are presented. Methods for testing and reducing the flammability and toxicity are discussed. Many commercially available composite systems are reported to provide favorable characteristics for marine applications. Although there seems to be a need for improved production technology for thermoplastics, they present potential advantages in physical properties over thermoset composites.

关键词： Composite materials

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THE UNITED STATES NAVY'S “DESIGN WORK STUDY” APPROACH TO THE DEVELOPMENT OF SHIPBOARD CONTROL SYSTEMS

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Naval Engineers Journal 1976年第6期88卷 62-74页

作者： PLATO, ARTIS I. GAMBREL, WILLIAM DAVID Artis I. Plato:is Head of the Design Work Study/ Shipboard Manning/Human Factors Engineering Section Systems Engineering and Analysis Branch Naval Ship Engineering Center (NAVSEC). He graduated from the City College of New York in 1956 receiving his Bachelor of Mechanical Engineering degree. Following this he started work at the New York Naval Shipyard in the Internal Combustion Engine and Cargo Elevator Section. During 1957 and 1958 he was called up for active duty with the U.S. Army Corps of Engineers and served in Europe with a Construction Engineer Battalion. After release from active duty he returned to the shipyard where he remained until 1961 when he transferred to the Naval Supply Research and Development Facility Bayonne New Jersey. Initially he was in charge of an Engineering Support Test Group and the drafting services for the whole Facility. Later he became a Project Engineer in the Food Services Facilities Branch with duties that included planning and designing new afloat and ashore messing facilities for the Navy. In 1966 he transferred to NAVSEC as a Project Engineer in the Design Work Study Section and in this capacity worked on selected projects and manning problems for new construction and also developed a computer program (Manpower Determination Model) that makes accurate crew predictions for feasibility studies. In 1969 he became Head of the Section. He has been active in the U.S. Army Reserve since his release from active duty and his duties have included command of an Engineer Company various Staff positions and his present assignment as Operations Officer for a Civil Affairs Group. He has completed the U. S. A rmy Corps of Engineers Career Course and the Civil Affairs Career Course and is presently enrolled in the U.S. Army Command and General Staff College non-resident course. Additionally he completed graduate studies at American University Washington D.C in 1972 receiving his MSTM degree in Technology of Management and is a member of ASE ASME CAA U. S. Naval Instit

The purpose of this paper is to discuss a system analysis technique called “Design Work Study”, that is used by the U.S. Navy for the development of improved ship control systems. The Design Work Study approach is one which brings about the most efficient and cost effective man‐machine combination for the ship control functions. Adherence to this process insures that the advantages of automation are balanced against incurred operational and maintenance expense. At present, U.S. Navy doctrine requires that certain ship operating stations, such as steering and propulsion control, be manned at specified ship conditions of readiness. Therefore, if personnel are needed to fulfill these combat environment obligations, excessive automation may only result in unnecessary additional acquisition costs and increased personnel skill requirements. The Design Work Study process can be applied to establish the required fine balance between the degree of built‐in automation and the shipboard manpower levels. In order to explain the techniques that are used for this process, the Authors will present a brief summary of the Design Work Study approach for optimizing shipboard control systems, including an explanation of the formal procedural tools that are applicable. In addition, a practical case study of ship control system design for one of the latest classes of Navy destroyers will be presented. This example will illustrate the resultant savings and benefits that can be realized by a judicious application of this technique. © 1976 American Society of Naval Engineers

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MARINE APPLICATIONS OF PLASTICS

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Journal of the American Society for Naval Engineers 1960年第4期72卷 609-622页

作者： OWEN, T.B. ALFERS, J.B. USN Captain Owen was commissioned in the Navy in 1940 upon graduation from the University of Washington where he received a Bachelor of Science degree in Chemical Engineering. After four years of service afloat during World War II and a brief tour in the Bureau of Naval Personnel he participated in the Navy officers' postgraduate training program. In 1950 he received the degree of Doctor of Philosophy in Physical Chemistry at Cornell University. After a year's work at the University of Amsterdam he was designated as an Engineering Duty Officer. He then returned to the United States for duty in the Naval Sciences Division of the Office of Naval Research. He was then transferred to the Long Beach Naval Shipyard where he served successively as Assistant Repair Superintendent and Production Control Superintendent. At the conclusion of this tour he was assigned to the Bureau of Ships as Head of the Materials Development Branch. He is now Director Applied Science Division of the Bureau. Captain Owen holds the Silver Star Medal Bronze Star Medal the Navy Unit Commendation and other area service awards. He is a member of the American Chemical Society Tau Beta Pi and Sigma Xi. Mr. Alfers graduated from Kansas State University with a degree in Electrical Engineering. He worked for several years with the Rural Electrification Administration on operation and maintenance of Rural Electric distribution systems. For the past 18 years he has worked in research and development and standardization of plastic and dielectric materials for the Bureau of Ships. At the present time he is Acting Head of the Section for Polymers Fibers and Packaging of the Material Development Branch. Mr. Alfers recently received a Master's degree in Engineering Administration from George Washington University. He has received the Distinguished Civilian Service Award from the Secretary of the Navy and the Executive Award from the Reinforced Plastics Division of the Society of the Plastics Industry. He is a member of the Society of Plastic Enginee

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