GeSn/Si Avalanche Photodetectors on Si substrates
2016-09-16
of processes for different photo detectors. In-depth of study has been conducted for GeSn photo conductors and photodiodes. A summary of the...The material growth mechanism was in-depth studied; secondly, the material and optical characterizations have been conducted , including SEM, TEM, XRD...investigated. The material growth mechanism was in-depth studied; secondly, the material and optical characterizations have been conducted , including
Evaluation of Dielectric-Barrier-Discharge Actuator Substrate Materials
NASA Technical Reports Server (NTRS)
Wilkinson, Stephen P.; Siochi, Emilie J.; Sauti, Godfrey; Xu, Tian-Bing; Meador, Mary Ann; Guo, Haiquan
2014-01-01
A key, enabling element of a dielectric barrier discharge (DBD) actuator is the dielectric substrate material. While various investigators have studied the performance of different homogeneous materials, most often in the context of related DBD experiments, fundamental studies focused solely on the dielectric materials have received less attention. The purpose of this study was to conduct an experimental assessment of the body-force-generating performance of a wide range of dielectric materials in search of opportunities to improve DBD actuator performance. Materials studied included commonly available plastics and glasses as well as a custom-fabricated polyimide aerogel. Diagnostics included static induced thrust, electrical circuit parameters for 2D surface discharges and 1D volume discharges, and dielectric material properties. Lumped-parameter circuit simulations for the 1D case were conducted showing good correspondence to experimental data provided that stray capacitances are included. The effect of atmospheric humidity on DBD performance was studied showing a large influence on thrust. The main conclusion is that for homogeneous, dielectric materials at forcing voltages less than that required for streamer formation, the material chemical composition appears to have no effect on body force generation when actuator impedance is properly accounted for.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1974-02-01
The materials investigations under the HSST program are divided into studies of unirradiated materials and studies of irradiation effects. The studies of unirradiated materials, which include inspection, characterization, metallurgy, variability determinations, transition temperature investigations, fracture mechanics studies, and fatigue-crack propagation tests, are discussed. The investigations of irradiated materials include studies of radiation effects on A-533-B steel. Results of studies on thick pressure vessels and pipes of ASTM A508 steel are also reported along with results of studies on Mode III crack extension in reactor piping. (JRD)
Studies of molecular properties of polymeric materials
NASA Technical Reports Server (NTRS)
Harries, W. L.; Long, Sheila Ann T.; Long, Edward R., Jr.
1990-01-01
Aerospace environment effects (high energy electrons, thermal cycling, atomic oxygen, and aircraft fluids) on polymeric and composite materials considered for structural use in spacecraft and advanced aircraft are examined. These materials include Mylar, Ultem, and Kapton. In addition to providing information on the behavior of the materials, attempts are made to relate the measurements to the molecular processes occurring in the material. A summary and overview of the technical aspects are given along with a list of the papers that resulted from the studies. The actual papers are included in the appendices and a glossary of technical terms and definitions is included in the front matter.
An Evaluation of Some Motivational Materials Related to the History of Mathematics.
ERIC Educational Resources Information Center
Fraser, Barry J.; Koop, Anthony J.
This report evaluates motivational materials related to the history of mathematics. Materials produced included plays, written articles, slide-tape presentations, and videotapes. Two of these, plays and written articles, were chosen for intensive study. The study included a survey of teacher opinion, a student questionnaire, and evaluations by…
Design and material selection for inverter transformer cores
NASA Technical Reports Server (NTRS)
Mclyman, W. T.
1973-01-01
Report is announced which studied magnetic properties of candidate materials for use in spacecraft transformers, static inverters, converters, and transformer-rectifier power supplies. Included are material characteristics for available alloy compositions in tabular form, including: trade names, saturated flux density, dc coercive force, loop squareness, material density, and watts per pound at 3 KHz.
Tribological properties of amorphous alloys and the role of surfaces in abrasive wear of materials
NASA Technical Reports Server (NTRS)
Miyoshi, K.; Buckley, D. H.
1982-01-01
The research approach undertaken by the authors relative to the subject, and examples of results from the authors are reviewed. The studies include programs in adhesion, friction, and various wear mechanisms (adhesive and abrasive wear). The materials which have been studied include such ceramic and metallic materials as silicon carbide, ferrites, diamond, and amorphous alloys.
Ultra-High Temperature Materials Characterization for Propulsion Applications
NASA Technical Reports Server (NTRS)
Rogers, Jan; Hyers, Robert
2007-01-01
Propulsion system efficiency increases as operating temperatures are increased. Some very high-temperature materials are being developed, including refractory metal alloys, carbides, borides, and silicides. System design requires data for materials properties at operating temperatures. Materials property data are not available for many materials of interest at the desired operating temperatures (up to approx. 3000 K). The objective of this work is to provide important physical property data at ultra-high temperatures. The MSFC Electrostatic levitation (ESL) facility can provide measurements of thermophysical properties which include: creep strength, density and thermal expansion for materials being developed for propulsion applications. The ESL facility uses electrostatic fields to position samples between electrodes during processing and characterization studies. Because the samples float between the electrodes during studies, they are free from any contact with a container or test apparatus. This provides a high purity environment for the study of high-temperature, reactive materials. ESL can be used to process a wide variety of materials including metals, alloys, ceramics, glasses and semiconductors. The MSFC ESL has provided non-contact measurements of properties of materials up to 3400 C. Density and thermal expansion are measured by analyzing digital images of the sample at different temperatures. Our novel, non-contact method for measuring creep uses rapid rotation to deform the sample. Digital images of the deformed samples are analyzed to obtain the creep properties, which match those obtained using ASTM Standard E-139 for Nb at 1985 C. Data from selected ESL-based characterization studies will be presented. The ESL technique could support numerous propulsion technologies by advancing the knowledge base and the technology readiness level for ultra-high temperature materials. Applications include non-eroding nozzle materials and lightweight, high-temperature alloys for turbines and structures.
An Overview of the MSFC Electrostatic Levitation Facility
NASA Technical Reports Server (NTRS)
Rogers, J. R.; Robinson, M. B.; Hyers, R. W.; Savage, L.; Rathz, T.
2000-01-01
Electrostatic levitation (ESL) provides a means to study molten materials in a contamination-free environment, including no contact with a container. Many phenomena important to materials science can be studied in the ESL. Solidification of metals, alloys and undercooled materials represent an important topic for research in the ESL. Recent studies of metals and alloys during solidification in the ESL are reported. Measurements include time, temperature and transformation of metallic glass-forming alloys, solidification velocities, and microstructure. This multimedia report includes a video clip showing processing in the ESL, with descriptions of the different segments in the text.
Moiseeva, Natalia S; Kunin, Anatoly A
2018-03-01
Restorative filling materials used for dental caries prevention and treatment consist of various components including monomers or oligomers, which play a significant role in forming the main structure of these materials, as well as in characterising their physical, mechanical and chemical properties. The necessity for the development and improvement of structural characteristics of polymeric dental filling materials intended for caries prevention and their life duration increase served as the initiating factor of our research. According to the research purpose and challenges, we studied the changes in the physical, mechanical and chemical properties of composite filling materials with and without electromagnetic field influence. The investigations in vivo include the study of microstructural features of polymeric filling materials by scanning electron microscopy (SEM) and the investigations in vitro include the study of sealed and extracted human teeth chips by using X-ray spectral analysis. We also evaluated the changes in the strength characteristics of dental filling materials with and without electromagnetic field influence. The analysis of the obtained data indicates the presence of structural changes in polymeric dental filling materials, including the material microstructure condensation confirmed by the SEM results, an increase in the strength and adhesion characteristics and certain regularities of the chemical elemental composition concentration change in the area of hard tooth tissue and dental filling material. These scientific data will provide tooth caries prevention and promote the increase of treatment quality.
Ultra-High Temperature Materials Characterization for Space and Missile Applications
NASA Technical Reports Server (NTRS)
Rogers, Jan; Hyers, Robert
2007-01-01
Numerous advanced space and missile technologies including propulsion systems require operations at high temperatures. Some very high-temperature materials are being developed to meet these needs, including refractory metal alloys, carbides, borides, and silicides. System design requires data for materials properties at operating temperatures. Materials property data are not available at the desired operating temperatures for many materials of interest. The objective of this work is to provide important physical property data at ultra-high temperatures. The MSFC Electrostatic Levitation (ESL) facility can provide measurements of thermophysical properties which include: creep strength, emissivity, density and thermal expansion. ESL uses electrostatic fields to position samples between electrodes during processing and characterization experiments. Samples float between the electrodes during studies and are free from any contact with a container or test apparatus. This provides a high purity environment for the study of high-temperature, reactive materials. ESL can be used to process a wide variety of materials including metals, alloys, ceramics, glasses and semiconductors. A system for the determination of total hemispherical emissivity is being developed for the MSFC ESL facility by AZ Technology Inc. The instrument has been designed to provide emissivity measurements for samples during ESL experiments over the temperature range 700-3400K. A novel non-contact technique for the determination of high-temperature creep strength has been developed. Data from selected ESL-based characterization studies will be presented. The ESL technique could advance space and missile technologies by advancing the knowledge base and the technology readiness level for ultra-high temperature materials. Applications include non-eroding nozzle materials and lightweight, high-temperature alloys for turbines and structures.
Recycled materials in Portland cement concrete
DOT National Transportation Integrated Search
2000-06-01
This report pertains to a comprehensive study involving the use of recycled materials in Portland cement concrete. Three different materials were studied including crushed glass (CG), street sweepings (SS), and recycled concrete (RC). Blast furnace s...
How Do I Manage? An Introduction to Management. Supplementary Material and Workbook.
ERIC Educational Resources Information Center
North West Regional Management Centre, Chorley (England).
This book contains supplementary material for a British self-study course in management designed as an introduction to the course for the Certificate in Management Studies. The materials in this book are learning activities referenced to various topics in the course materials. The nine activities include a case study of a production supervision…
NASA Technical Reports Server (NTRS)
Boyce, Lola; Bast, Callie C.
1992-01-01
The research included ongoing development of methodology that provides probabilistic lifetime strength of aerospace materials via computational simulation. A probabilistic material strength degradation model, in the form of a randomized multifactor interaction equation, is postulated for strength degradation of structural components of aerospace propulsion systems subjected to a number of effects or primative variables. These primative variable may include high temperature, fatigue or creep. In most cases, strength is reduced as a result of the action of a variable. This multifactor interaction strength degradation equation has been randomized and is included in the computer program, PROMISS. Also included in the research is the development of methodology to calibrate the above described constitutive equation using actual experimental materials data together with linear regression of that data, thereby predicting values for the empirical material constraints for each effect or primative variable. This regression methodology is included in the computer program, PROMISC. Actual experimental materials data were obtained from the open literature for materials typically of interest to those studying aerospace propulsion system components. Material data for Inconel 718 was analyzed using the developed methodology.
Object Lessons: Thinking about Material Culture
ERIC Educational Resources Information Center
Burkhart, Anne
2006-01-01
This article describes why art educators might consider studying material forms from everyday life, presents suggestions for exploring them in an art classroom, and includes an example to illustrate teaching about an object of material culture. The author presents reasons for studying material culture in the art classroom and offers suggestions…
Development of seal ring carbon-graphite materials (tasks 8, 9, and 10)
NASA Technical Reports Server (NTRS)
Fechter, N. J.; Petrunich, P. S.
1973-01-01
A screening study was conducted to develop improved carbon-graphite materials for use in self-acting seals at air temperatures to 1300 F (704 C). Property measurements on materials prepared during this study have shown that: (1) The mechanical properties of a carbon-graphite material were significantly improved by using a fine milled artificial graphite filler material and including intensive mixing, warm molding, and pitch impregnation in the processing; and (2) the oxidation resistance of a carbon-graphite material was improved by including fine milled boron carbide as an oxidation-inhibiting additive. These techniques were employed to develop a material that has 10 times more oxidation resistance than that of a widely used commercial grade and mechanical properties that approach those of the commercial grade.
Reversible creation of nanostructures between identical or different species of materials
NASA Astrophysics Data System (ADS)
Jang, Hyun-Ik; Ko, Sungho; Park, Junyong; Lee, Dong-Eon; Jeon, Seokwoo; Ahn, Chi Won; Yoo, Kwang Soo; Park, Jae Hong
2012-07-01
In this study, accurate nanostructures with various aspect ratios are created on several types of material. This work is highly applicable to the energy, optical, and nano-bio fields, for example. A silicon (Si) nano-mold is preserved using the method described, and target nanostructures are replicated reversibly and unlimitedly to or from various hard and soft materials. It is also verified that various materials can be applied to the substrates. The results confirm that the target nanostructures are successfully created in precise straight line structures and circle structures with various aspect ratios, including extremely high aspect ratios of 1:18. It is suggested that the optimal replicating and demolding process of nanostructures with high aspect ratios, which are the most problematic, could be controlled by means of the surface energy between the functional materials. Relevant numerical and analytical studies are also performed. It is possible to expand the applicability of the nanostructured mold by adopting various backing materials, including rounded substrates. The scope of the applications is extended further by transferring the nanostructures between different species of materials including metallic materials as well as identical species.
Analysis of the Nature and Impact of Social Studies Curriculum Project Materials.
ERIC Educational Resources Information Center
Cornbleth, Catherine
The study describes the use, popularity, and effectiveness of selected social studies curriculum project materials (CPMs). Five multistate surveys identified 11 CPMs which were judged to be widely used and therefore served as the basis for the study. These included materials from the High School Geography Project, Anthropology Curriculum Study…
Suzuki, Shunsuke; Mori, Shinsuke
2017-08-01
Particulate matter from a diesel engine, including soot and carbon nanomaterials, was collected on a sampling holder and the structure of the materials was studied by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). As a result of employing gas oil/ethanol mixing fuel with sulfur and ferrocene/molybdenum as catalyst sources, formation of carbon nanotubes (CNT)-like materials in addition to soot was observed in the exhaust gas from a diesel engine. It was revealed that CNT-like materials were included among soot in our system only when the following three conditions were satisfied simultaneously: high ethanol fraction in fuel, high sulfur loading, and presence of catalyst sources in fuel. This study confirmed that if at least one of these three conditions was not satisfied, CNT-like materials were not observed in the exhaust from a diesel engine. These experimental results shown in this work provide insights into understanding CNT-like material formation mechanism in a diesel engine. Recent papers reported that carbon nanotube-like materials were included in the exhaust gas from engines, but conditions for carbon nanotube-like material formation have not been well studied. This work provides the required conditions for carbon nanotube-like material growth in a diesel engine, and this will be helpful for understanding the carbon nanotube-like material formation mechanism and taking countermeasures to preventing carbon nanotube-like material formation in a diesel engine.
ERIC Educational Resources Information Center
Haberbosch, John F.; And Others
Readings and audiovisual materials, selected especially for educators, related to the study of Afro-American, Hispano-American, and American Indian cultures are included in this 366-item annotated bibliography covering the period from 1861 to 1968. Historical, cultural, and biographical materials are included for each of the three cultures as well…
ERIC Educational Resources Information Center
SysteMetrics, Inc., Santa Barbara, CA.
Provided are appendices for a study which examined the relationship between graduate medical education (GME) and practice profiles in three specialties: family practice, psychiatry, and obstetrics/gynecology. Appendix A includes materials related to methodology of the study. Appendices B-D include supplementary materials for family practice,…
The stability and transport of radio-labeled Fe2O3 particles were studied using laboratory batch and column techniques. Core material collected from shallow sand and gravel aquifer was used as the immobile column matrix material. Variables in the study included flow rate, pH, i...
Removing Supplementary Materials from Montessori Classrooms Changed Child Outcomes
ERIC Educational Resources Information Center
Lillard, Angeline S.; Heise, Megan J.
2016-01-01
Montessori classrooms vary in the degree to which they adhere to Maria Montessori's model, including in the provision of materials. Specifically, some classrooms use only Montessori materials, whereas others supplement the Montessori materials with commercially available materials like puzzles and games. A prior study suggested such…
Chemistry and Materials Science progress report, FY 1994. Revision 2
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1996-01-01
Thrust areas of the weapons-supporting research include surface science, fundamentals of the physics and processing of metals, energetic materials, etc. The laboratory directed R and D include director`s initiatives, individual projects, and transactinium science studies.
Non-Print Social Studies Materials--Elementary School Level.
ERIC Educational Resources Information Center
Lynn, Karen
Types of non-print social studies materials developed for presentation to, and use by, elementary school students are identified. "Non-print" materials include films, filmstrips, video cassettes, audio recordings, computer databases, telecommunications, and hypertext. An explanation of why elementary school students can benefit from the use of…
NASA Technical Reports Server (NTRS)
Trottier, C. Michael
1996-01-01
Recently, scientists and engineers have investigated the advantages of smart materials and structures by including actuators in material systems for controlling and altering the response of structural environments. Applications of these materials systems include vibration suppression/isolation, precision positioning, damage detection and tunable devices. Some of the embedded materials being investigated for accomplishing these tasks include piezoelectric ceramics, shape memory alloys, and fiber optics. These materials have some benefits and some shortcomings; each is being studied for use in active material design in the SPICES (Synthesis and Processing of Intelligent Cost Effective Structures) Consortium. The focus of this paper concerns the manufacturing aspects of smart structures by incorporating piezoelectric ceramics, shape memory alloys and fiber optics in a reinforced thermoset matrix via resin transfer molding (RTM).
Materials science with muon spin rotation
NASA Technical Reports Server (NTRS)
1988-01-01
During this reporting period, the focus of activity in the Materials Science with Muon Spin Rotation (MSMSR) program was muon spin rotation studies of superconducting materials, in particular the high critical temperature and heavy-fermion materials. Apart from these studies, work was continued on the analysis of muon motion in metal hydrides. Results of these experiments are described in six papers included as appendices.
Survey Analysis of Materials Processing Experiments Aboard STS-47: Spacelab J
NASA Technical Reports Server (NTRS)
Sharpe, R. J.; Wright, M. D.
2009-01-01
This Technical Memorandum (TM) is a survey outline of materials processing experiments aboard Space Shuttle Mission STS-47: Spacelab J, a joint venture between NASA and the National Space Development Agency of Japan. The mission explored materials processing experiments including electronics and crystal growth materials, metals and alloys, glasses and ceramics, and fluids. Experiments covered include Growth of Silicone Spherical Crystals and Surface Oxidation, Growth Experiment of Narrow Band-Gap Semiconductor Lead-Tin-Tellurium Crystals in Space, Study on Solidification of Immiscible Alloys, Fabrication of Very-Low-Density, High-Stiffness Carbon Fiber/Aluminum Hybridized Composites, High Temperature Behavior of Glass, and Study of Bubble Behavior. The TM underscores the historical significance of these experiments in the context of materials processing in space.
Optimal Experiment Design for Thermal Characterization of Functionally Graded Materials
NASA Technical Reports Server (NTRS)
Cole, Kevin D.
2003-01-01
The purpose of the project was to investigate methods to accurately verify that designed , materials meet thermal specifications. The project involved heat transfer calculations and optimization studies, and no laboratory experiments were performed. One part of the research involved study of materials in which conduction heat transfer predominates. Results include techniques to choose among several experimental designs, and protocols for determining the optimum experimental conditions for determination of thermal properties. Metal foam materials were also studied in which both conduction and radiation heat transfer are present. Results of this work include procedures to optimize the design of experiments to accurately measure both conductive and radiative thermal properties. Detailed results in the form of three journal papers have been appended to this report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mandell, John F.; Ashwill, Thomas D.; Wilson, Timothy J.
This report presents an analysis of trends in fatigue results from the Montana State University program on the fatigue of composite materials for wind turbine blades for the period 2005-2009. Test data can be found in the SNL/MSU/DOE Fatigue of Composite Materials Database which is updated annually. This is the fifth report in this series, which summarizes progress of the overall program since its inception in 1989. The primary thrust of this program has been research and testing of a broad range of structural laminate materials of interest to blade structures. The report is focused on current types of infusedmore » and prepreg blade materials, either processed in-house or by industry partners. Trends in static and fatigue performance are analyzed for a range of materials, geometries and loading conditions. Materials include: sixteen resins of three general types, five epoxy based paste adhesives, fifteen reinforcing fabrics including three fiber types, three prepregs, many laminate lay-ups and process variations. Significant differences in static and fatigue performance and delamination resistance are quantified for particular materials and process conditions. When blades do fail, the likely cause is fatigue in the structural detail areas or at major flaws. The program is focused strongly on these issues in addition to standard laminates. Structural detail tests allow evaluation of various blade materials options in the context of more realistic representations of blade structure than do the standard test methods. Types of structural details addressed in this report include ply drops used in thickness tapering, and adhesive joints, each tested over a range of fatigue loading conditions. Ply drop studies were in two areas: (1) a combined experimental and finite element study of basic ply drop delamination parameters for glass and carbon prepreg laminates, and (2) the development of a complex structured resin-infused coupon including ply drops, for comparison studies of various resins, fabrics and pry drop thicknesses. Adhesive joint tests using typical blade adhesives included both generic testing of materials parameters using a notched-lap-shear test geometry developed in this study, and also a series of simulated blade web joint geometries fabricated by an industry partner.« less
Fate and Transport of Chemical Warfare Agents VX and HD ...
Report The intent of this investigation was to study the fate and transport of CWA applied to painted/sealed materials including the potential partitioning of CWA into permeable paints/sealants and subsequently into underlying porous materials. Based on the results obtained from this investigation, VX and sulfur mustard (HD) have the ability to permeate into paints and sealants, including in some cases the underlying porous materials. It is likely that other permeable materials besides paints and sealants may also show similar behavior.
NASA Technical Reports Server (NTRS)
1983-01-01
Mission areas analyzed for input to the baseline mission model include: (1) commercial materials processing, including representative missions for producing metallurgical, chemical and biological products; (2) commercial Earth observation, represented by a typical carry-on mission amenable to commercialization; (3) solar terrestrial and resource observations including missions in geoscience and scientific land observation; (4) global environment, including representative missions in meteorology, climatology, ocean science, and atmospheric science; (5) materials science, including missions for measuring material properties, studying chemical reactions and utilizing the high vacuum-pumping capacity of space; and (6) life sciences with experiments in biomedicine and animal and plant biology.
The Development of Interactive Mathematics Learning Material Based on Local Wisdom with .swf Format
NASA Astrophysics Data System (ADS)
Abadi, M. K.; Asih, E. C. M.; Jupri, A.
2018-05-01
Learning materials used by students and schools in Serang district are lacking because they do not contain local wisdom content. The aim of this study is to improve the deficiencies in learning materials used by students by making interactive materials based on local wisdom content with format .swf. The method in this research is research and development (RnD) with ADDIE model. In making this interactive learning materials in accordance with the stages of the ADDIE study. The results of this study include interactive learning materials based on local wisdom. This learning material is suitable for digital students.
Polymeric materials science in the microgravity environment
NASA Technical Reports Server (NTRS)
Coulter, Daniel R.
1989-01-01
The microgravity environment presents some interesting possibilities for the study of polymer science. Properties of polymeric materials depend heavily on their processing history and environment. Thus, there seem to be some potentially interesting and useful new materials that could be developed. The requirements for studying polymeric materials are in general much less rigorous than those developed for studying metals, for example. Many of the techniques developed for working with other materials, including heat sources, thermal control hardware and noncontact temperature measurement schemes should meet the needs of the polymer scientist.
NASA Astrophysics Data System (ADS)
Covino, J.; Bennett, J. M.
1986-03-01
Material properties of low-expansion glass and glass-ceramic materials have been measured. The materials that have been characterized are ultralow-expansion (ULE) type 7971 quartz, a new glass-ceramic material RLA 559,122 from Corning Glass Works, fused quartz from General Electric, Zerodur from Schott Glaswerke, and Cervit C-101 from Owens-Illinois. Characterization has included measurements of X-ray powder diffraction patterns, some elemental analyses, helium permeability, thermal expansion, particle-size distributions, optical properties, and optical finish studies.
Materials for Secondary School Programs for the Educable Mentally Retarded Adolescent.
ERIC Educational Resources Information Center
Boston Univ., MA. New England Special Education Instructional Materials Center.
Compiled are materials related to work study programs for the educable mentally handicapped adolescent. Items listed include professional books, textbooks, resource aids, journals and articles, curriculum guides, instructional materials, and audiovisual aids. The materials are grouped according to academic areas (mathematics, science, social…
NASA Technical Reports Server (NTRS)
Lovejoy, Andrew E.; Hilburger, Mark W.; Chunchu, Prasad B.
2010-01-01
A design study was conducted to investigate the effect shell buckling knockdown factor (SBKF), internal pressure and aluminum alloy material selection on the structural weight of stiffened cylindrical shells. Two structural optimization codes were used for the design study to determine the optimum minimum-weight design for a series of design cases, and included an in-house developed genetic algorithm (GA) code and PANDA2. Each design case specified a unique set of geometry, material, knockdown factor combinations and loads. The resulting designs were examined and compared to determine the effects of SBKF, internal pressure and material selection on the acreage design weight and controlling failure mode. This design study shows that use of less conservative SBKF values, including internal pressure, and proper selection of material alloy can result in significant weight savings for stiffened cylinders. In particular, buckling-critical cylinders with integrally machined stiffener construction can benefit from the use of thicker plate material that enables taller stiffeners, even when the stiffness, strength and density properties of these materials appear to be inferior.
Spanish-speaking Americans. Ethnic Heritage Studies Program of Rhode Island, Appendix C.
ERIC Educational Resources Information Center
Navascues, Michael, Comp.
Reading materials by Spanish-speaking Americans, which constitute curricular materials for secondary school and college ethnic studies programs, are presented. The selection includes five stories and a poem in Spanish and an essay and autobiographical narrative in English. The writers of the materials represent the following areas: Columbia,…
Shopping Centers: Their Development and Impact on a Community.
ERIC Educational Resources Information Center
Berezowski, P. E.; And Others
Presenting extensive background material on the development of shopping centers, this paper includes elementary and junior high school outdoor education activities centering upon shopping center studies. Background material includes analysis of the following: shopping center types (architecture, regional location, etc); land use (guidelines for…
Cell-based composite materials with programmed structures and functions
None
2016-03-01
The present invention is directed to the use of silicic acid to transform biological materials, including cellular architecture into inorganic materials to provide biocomposites (nanomaterials) with stabilized structure and function. In the present invention, there has been discovered a means to stabilize the structure and function of biological materials, including cells, biomolecules, peptides, proteins (especially including enzymes), lipids, lipid vesicles, polysaccharides, cytoskeletal filaments, tissue and organs with silicic acid such that these materials may be used as biocomposites. In many instances, these materials retain their original biological activity and may be used in harsh conditions which would otherwise destroy the integrity of the biological material. In certain instances, these biomaterials may be storage stable for long periods of time and reconstituted after storage to return the biological material back to its original form. In addition, by exposing an entire cell to form CSCs, the CSCs may function to provide a unique system to study enzymes or a cascade of enzymes which are otherwise unavailable.
Cell-based composite materials with programmed structures and functions
Kaehr, Bryan J.; Brinker, C. Jeffrey; Townson, Jason L.
2018-05-15
The present invention is directed to the use of silicic acid to transform biological materials, including cellular architecture into inorganic materials to provide biocomposites (nanomaterials) with stabilized structure and function. In the present invention, there has been discovered a means to stabilize the structure and function of biological materials, including cells, biomolecules, peptides, proteins (especially including enzymes), lipids, lipid vesicles, polysaccharides, cytoskeletal filaments, tissue and organs with silicic acid such that these materials may be used as biocomposites. In many instances, these materials retain their original biological activity and may be used in harsh conditions which would otherwise destroy the integrity of the biological material. In certain instances, these biomaterials may be storage stable for long periods of time and reconstituted after storage to return the biological material back to its original form. In addition, by exposing an entire cell to form CSCs, the CSCs may function to provide a unique system to study enzymes or a cascade of enzymes which are otherwise unavailable.
Mass of materials: the impact of designers on construction ergonomics.
Smallwood, John
2012-01-01
Many construction injuries are musculoskeletal related in the form of sprains and strains arising from the handling of materials, which are specified by designers. The paper presents the results of a study conducted among delegates attending two 'designing for H&S' (DfH&S) seminars using a questionnaire. The salient findings include: the level of knowledge relative to the mass and density of materials is limited; designers generally do not consider the mass and density of materials when designing structures and elements and specifying materials; to a degree designers appreciate that the mass and density of materials impact on construction ergonomics; designers rate their knowledge of the mass and density of materials as limited, and designers appreciate the potential of the consideration of the mass and density of materials to contribute to an improvement in construction ergonomics. Conclusions include: designers lack the requisite knowledge relative to the mass and density of materials; designers are thus precluded from conducting optimum design hazard identification and risk assessments, and tertiary built environment designer education does not enlighten designers relative to construction ergonomics. Recommendations include: tertiary built environment designer education should construction ergonomics; professional associations should raise the level of awareness relative to construction ergonomics, and design practices should include a category 'mass and density of materials' in their practice libraries.
Guidance for conducting hazardous materials flow surveys
DOT National Transportation Integrated Search
1995-01-01
This report provides guidance on how to conduct a commodity flow study for hazardous materials moving by highway. It discusses the need for this type of study and details how to review baseline information and design the study. It includes examples a...
Structural Materials and Fuels for Space Power Plants
NASA Technical Reports Server (NTRS)
Bowman, Cheryl; Busby, Jeremy; Porter, Douglas
2008-01-01
A fission reactor combined with Stirling convertor power generation is one promising candidate in on-going Fission Surface Power (FSP) studies for future lunar and Martian bases. There are many challenges for designing and qualifying space-rated nuclear power plants. In order to have an affordable and sustainable program, NASA and DOE designers want to build upon the extensive foundation in nuclear fuels and structural materials. This talk will outline the current Fission Surface Power program and outline baseline design options for a lunar power plant with an emphasis on materials challenges. NASA first organized an Affordable Fission Surface Power System Study Team to establish a reference design that could be scrutinized for technical and fiscal feasibility. Previous papers and presentations have discussed this study process in detail. Considerations for the reference design included that no significant nuclear technology, fuels, or material development were required for near term use. The desire was to build upon terrestrial-derived reactor technology including conventional fuels and materials. Here we will present an overview of the reference design, Figure 1, and examine the materials choices. The system definition included analysis and recommendations for power level and life, plant configuration, shielding approach, reactor type, and power conversion type. It is important to note that this is just one concept undergoing refinement. The design team, however, understands that materials selection and improvement must be an integral part of the system development.
Electronic Structure Theory | Materials Science | NREL
design and discover materials for energy applications. This includes detailed studies of the physical computing. Key Research Areas Materials by Design NREL leads the U.S. Department of Energy's Center for Next Generation of Materials by Design, which incorporates metastability and synthesizability. Learn more about
Life Science Research Facility materials management requirements and concepts
NASA Technical Reports Server (NTRS)
Johnson, Catherine C.
1986-01-01
The Advanced Programs Office at NASA Ames Research Center has defined hypothetical experiments for a 90-day mission on Space Station to allow analysis of the materials necessary to conduct the experiments and to assess the impact on waste processing of recyclable materials and storage requirements of samples to be returned to earth for analysis as well as of nonrecyclable materials. The materials include the specimens themselves, the food, water, and gases necessary to maintain them, the expendables necessary to conduct the experiments, and the metabolic products of the specimens. This study defines the volumes, flow rates, and states of these materials. Process concepts for materials handling will include a cage cleaner, trash compactor, biological stabilizer, and various recycling devices.
Evaluation available encapsulation materials for low-cost long-life silicon photovoltaic arrays
NASA Technical Reports Server (NTRS)
Carmichael, D. C.; Gaines, G. B.; Noel, G. T.; Sliemers, F. A.; Nance, G. P.; Bunk, A. R.; Brockway, M. C.
1978-01-01
Experimental evaluation of selected encapsulation designs and materials based on an earlier study which have potential for use in low cost, long-life photovoltaic arrays are reported. The performance of candidate materials and encapsulated cells were evaluated principally for three types of encapsulation designs based on their potentially low materials and processing costs: (1) polymeric coatings, transparent conformal coatings over the cell with a structural-support substrate; (2) polymeric film lamination, cells laminated between two films or sheets of polymeric materials; and (3) glass-covered systems, cells adhesively bonded to a glass cover (superstrate) with a polymeric pottant and a glass or other substrate material. Several other design types, including those utilizing polymer sheet and pottant materials, were also included in the investigation.
ERIC Educational Resources Information Center
Delaware Univ., Newark. Coll. of Education.
This publication includes several activities regarding the use of nuclear power plants and possible effects on the environment. The materials are designed for secondary school students and include reference materials and masters for transparencies. (RH)
Metals and Ceramics Division annual progress report, October 1, 1978-June 30, 1979
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peterson, S.
Research is reported concerning: (1) engineering materials including materials compatibility, mechanical properties, nondestructive testing, pressure vessel technology, and welding and brazing; (2) fuels and processes consisting of ceramic technology, fuel cycle technology, fuels evaluation, fuels fabrication and metals processing; and (3) materials science which includes, ceramic studies, physical metallurgy and properties, radiation effects and microstructural analysis, metastable and superconducting materials, structure and properties of surfaces, theoretical research, and x-ray research and applications. Highlights of the work of the metallographic group and the current status of the High-Temperature Materials Laboratory (HTML) and the Materials and Structures Technology Management Center (MSTMC) aremore » presented. (FS)« less
Reduction of minimum required weight of cementitious materials in WisDOT concrete mixes.
DOT National Transportation Integrated Search
2011-12-01
"This project was designed to explore the feasibility of lowering the cementitious materials content : (CMC) used in Wisconsin concrete pavement construction. The cementitious materials studied included : portland cement, fly ash, and ground granulat...
Reduction of minimum required weight of cementitious materials in WisDOT concrete mixes.
DOT National Transportation Integrated Search
2011-12-01
This project was designed to explore the feasibility of lowering the cementitious materials content : (CMC) used in Wisconsin concrete pavement construction. The cementitious materials studied included : portland cement, fly ash, and ground granulate...
Rohr, Annette; McDonald, Jacob
2016-02-01
Air pollution is a complex mixture of gas-, vapor-, and particulate-phase materials comprised of inorganic and organic species. Many of these components have been associated with adverse health effects in epidemiological and toxicological studies, including a broad spectrum of carbonaceous atmospheric components. This paper reviews recent literature on the health impacts of organic aerosols, with a focus on specific sources of organic material; it is not intended to be a comprehensive review of all the available literature. Specific emission sources reviewed include engine emissions, wood/biomass combustion emissions, biogenic emissions and secondary organic aerosol (SOA), resuspended road dust, tire and brake wear, and cooking emissions. In addition, recent findings from large toxicological and epidemiological research programs are reviewed in the context of organic PM, including SPHERES, NPACT, NERC, ACES, and TERESA. A review of the extant literature suggests that there are clear health impacts from emissions containing carbon-containing PM, but difficulty remains in apportioning responses to certain groupings of carbonaceous materials, such as organic and elemental carbon, condensed and gas phases, and primary and secondary material. More focused epidemiological and toxicological studies, including increased characterization of organic materials, would increase understanding of this issue.
ERIC Educational Resources Information Center
Salam, S.
2017-01-01
The purpose of this research was to describe the need of development of "Reading Comprehension" teaching materials to students and lecturers of Indonesian Language and Literature Education Department, Gorontalo. This research is included in the research and development to develop educational products in the form of teaching materials.…
Spring 2005 Industry Study. Strategic Materials
2005-01-01
Research Laboratory, Weapons and Materials Research Center. Presented at ARL, Aberdeen, MD. March 17, 2005. Ashley, Steven. “ Alchemy of a...Spring 2005 Industry Study Final Report Strategic Materials The Industrial College of the Armed Forces National...the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data
Plant Hormones: How They Affect Root Formation.
ERIC Educational Resources Information Center
Reinhard, Diana Hereda
This science study aid, produced by the U.S. Department of Agriculture, includes a series of plant rooting activities for secondary science classes. The material in the pamphlet is written for students and includes background information on plant hormones, a vocabulary list, and five learning activities. Objectives, needed materials, and…
Fractography of modern engineering materials: Composites and metals, Second volume
DOE Office of Scientific and Technical Information (OSTI.GOV)
Masters, J.E.; Gilbertson, L.N.
1993-01-01
This book contains the manuscripts of eleven papers that were presented at the Second Symposium on Fractography of Modern Engineering Materials held in May 1992. The numerous advances in materials science in the six year period following the First Symposium dictated this second meeting. Not only had new materials been developed in the intervening years, but understanding of older materials had also progressed. Similarly, advances in the technology and the techniques of fractography had occurred. The objective of the symposium was to extend the colloquy on fractography to include these many advances. The paper may be divided into three sections:more » Unique Fractographic Techniques; Metallic Materials; Polymeric and Composite Materials. The section titles reflect the diversity of materials discussed in the meeting. The range of materials included cross-linked polyethylene, AISI 52100 steel, 2024 aluminum, and a variety of organic and metal matrix fibrous composites. The case studies presented also covered a wide range. They included failure investigations of an antenna used in deep space exploration and chemical storage tanks. Advances in the techniques of fractography were also reflected in a number of presentations; quantitative techniques and expert systems were also subjects of presentations. A short precis of each paper is included here to assist the readers in identifying works of particular interest.« less
Propellant material compatibility program and results
NASA Technical Reports Server (NTRS)
Toth, L. R.; Cannon, W. A.; Coulbert, C. D.; Long, H. R.
1976-01-01
The effects of long-term (up to 10 years) contact of inert materials with earth-storable propellants were studied for the purpose of designing chemical propulsion system components that can be used for current as well as future planetary spacecraft. The primary experimental work, and results to date are reported. Investigations include the following propellants: hydrazine, hydrazine-hydrazine nitrate blends, monomethyl-hydrazine, and nitrogen tetroxide. Materials include: aluminum alloys, corrosion-resistant steels, and titanium alloys. More than 700 test specimen capsules were placed in long-term storage testing at 43 C in the special material compatibility facility. Material ratings relative to the 10-year requirement have been assigned.
Arcjet Testing of Micro-Meteoroid Impacted Thermal Protection Materials
NASA Technical Reports Server (NTRS)
Agrawal, Parul; Munk, Michelle M.; Glaab, Louis J.
2013-01-01
There are several harsh space environments that could affect thermal protection systems and in turn pose risks to the atmospheric entry vehicles. These environments include micrometeoroid impact, extreme cold temperatures, and ionizing radiation during deep space cruise, all followed by atmospheric entry heating. To mitigate these risks, different thermal protection material samples were subjected to multiple tests, including hyper velocity impact, cold soak, irradiation, and arcjet testing, at various NASA facilities that simulated these environments. The materials included a variety of honeycomb packed ablative materials as well as carbon-based non-ablative thermal protection systems. The present paper describes the results of the multiple test campaign with a focus on arcjet testing of thermal protection materials. The tests showed promising results for ablative materials. However, the carbon-based non-ablative system presented some concerns regarding the potential risks to an entry vehicle. This study provides valuable information regarding the capability of various thermal protection materials to withstand harsh space environments, which is critical to sample return and planetary entry missions.
Atomic force microscopy for two-dimensional materials: A tutorial review
NASA Astrophysics Data System (ADS)
Zhang, Hang; Huang, Junxiang; Wang, Yongwei; Liu, Rui; Huai, Xiulan; Jiang, Jingjing; Anfuso, Chantelle
2018-01-01
Low dimensional materials exhibit distinct properties compared to their bulk counterparts. A plethora of examples have been demonstrated in two-dimensional (2-D) materials, including graphene and transition metal dichalcogenides (TMDCs). These novel and intriguing properties at the nano-, molecular- and even monatomic scales have triggered tremendous interest and research, from fundamental studies to practical applications and even device fabrication. The unique behaviors of 2-D materials result from the special structure-property relationships that exist between surface topographical variations and mechanical responses, electronic structures, optical characteristics, and electrochemical properties. These relationships are generally convoluted and sensitive to ambient and external perturbations. Characterizing these systems thus requires techniques capable of providing multidimensional information under controlled environments, such as atomic force microscopy (AFM). Today, AFM plays a key role in exploring the basic principles underlying the functionality of 2-D materials. In this tutorial review, we provide a brief introduction to some of the unique properties of 2-D materials, followed by a summary of the basic principles of AFM and the various AFM modes most appropriate for studying these systems. Following that, we will focus on five important properties of 2-D materials and their characterization in more detail, including recent literature examples. These properties include nanomechanics, nanoelectromechanics, nanoelectrics, nanospectroscopy, and nanoelectrochemistry.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shafrir, S.N.; Lambropoulos, J.C.; Jacobs, S.D.
2007-03-23
Surface features of tungsten carbide composites processed by bound abrasive deterministic microgrinding and magnetorheological finishing (MRF) were studied for five WC-Ni composites, including one binderless material. All the materials studied were nonmagnetic with different microstructures and mechanical properties. White-light interferometry, scanning electron microscopy, and atomic force microscopy were used to characterize the surfaces after various grinding steps, surface etching, and MRF spot-taking.
Burner Rig in the Material and Stresses Building
1969-11-21
A burner rig heats up a material sample in the Materials and Stresses Building at the National Aeronautics and Space Administration (NASA) Lewis Research Center. Materials technology is an important element in the successful development of advanced airbreathing and rocket propulsion systems. Different types of engines operate in different environments so an array of dependable materials is needed. NASA Lewis began investigating the characteristics of different materials shortly after World War II. In 1949 the materials group was expanded into its own division. The Lewis researchers sought to study and test materials in environments that simulate the environment in which they would operate. The Materials and Stresses Building, built in 1949, contained a number of laboratories to analyze the materials. They are subjected to high temperatures, high stresses, corrosion, irradiation, and hot gasses. The Physics of Solids Laboratory included a cyclotron, cloud chamber, helium cryostat, and metallurgy cave. The Metallographic Laboratory possessed six x-ray diffraction machines, two metalloscopes, and other equipment. The Furnace Room had two large induction machines, a 4500⁰ F graphite furnace, and heat treating equipment. The Powder Laboratory included 60-ton and 3000-ton presses. The Stresses Laboratory included stress rupture machines, fatigue machines, and tensile strength machines.
Florence Bascom and the Exclusion of Women From Earth Science Curriculum Materials
ERIC Educational Resources Information Center
Arnold, Lois
1975-01-01
Numerous excerpts from present day earth science curriculum materials reveal sexual discrimination. In addition, studies of photographs included in the materials reveal a high male dominance. The significant contributions of one earth scientist, Florence Bascom, are remembered. (CP)
Study of materials performance model for aircraft interiors
NASA Technical Reports Server (NTRS)
Leary, K.; Skratt, J.
1980-01-01
A demonstration version of an aircraft interior materials computer data library was developed and contains information on selected materials applicable to aircraft seats and wall panels, including materials for the following: panel face sheets, bond plies, honeycomb, foam, decorative film systems, seat cushions, adhesives, cushion reinforcements, fire blocking layers, slipcovers, decorative fabrics and thermoplastic parts. The information obtained for each material pertains to the material's performance in a fire scenario, selected material properties and several measures of processability.
NASA Technical Reports Server (NTRS)
1972-01-01
Materials and design technology of the all-silica LI-900 rigid surface insulation (RSI) thermal protection system (TPS) concept for the shuttle spacecraft is presented. All results of contract development efforts are documented. Engineering design and analysis of RSI strain arrestor plate material selections, sizing, and weight studies are reported. A shuttle prototype test panel was designed, analyzed, fabricated, and delivered. Thermophysical and mechanical properties of LI-900 were experimentally established and reported. Environmental tests, including simulations of shuttle loads represented by thermal response, turbulent duct, convective cycling, and chemical tolerance tests are described and results reported. Descriptions of material test samples and panels fabricated for testing are included. Descriptions of analytical sizing and design procedures are presented in a manner formulated to allow competent engineering organizations to perform rational design studies. Results of parametric studies involving material and system variables are reported. Material performance and design data are also delineated.
ERIC Educational Resources Information Center
Archenhold, W. F.; And Others
1987-01-01
Describes a new high school physics option in Great Britain which uses the model of a technological approach to the study of materials. Discusses the components of the program, including the development of a student book for independent learning and six case studies. Provides a case study about turbine blades. (TW)
ERIC Educational Resources Information Center
Gonen, Selahattin; Basaran, Bulent
2013-01-01
In the present study, a web site including instructional materials such as Whiteboard Movies (WBM), simulations and animations and testing materials such as true-false, fill-in-the-blanks, puzzles, open-ended questions and multiple-choice questions was designed. The study was carried out with 76 students attending Dicle College (DC), Diyarbakir…
Literature review on use of nonwood plant fibers for building materials and panels
John A. Youngquist; Brent E. English; Roger C. Scharmer; Poo Chow; Steven R. Shook
1994-01-01
The research studies included in this review focus on the use of nonwood plant fibers for building materials and panels. Studies address (1) methods for efficiently producing building materials and panels from nonwood plant fibers; (2) treatment of fibers prior to board production; (3) process variables, such as press time and temperature, press pressure, and type of...
Marshall Space Flight Center solid waste characterization and recycling improvement study
NASA Technical Reports Server (NTRS)
Eley, Michael H.; Crews, Lavonne; Johnston, Ben; Lee, David; Colebaugh, James
1995-01-01
The MSFC Facilities Office, which is responsible for disposing of all waste generated by MSFC, issued a delivery order to the University of Alabama in Huntsville (UAH) to characterize current MSFC waste streams and to evaluate their existing recycling program. The purpose of the study was to define the nature, quantity, and types of waste produced and to generate ideas for improving the present recycling program. Specifically, the following tasks were to be performed: Identify various surplus and waste materials--as identified by the Contracting Officer's Technical Representative (COTR)--by source, location, and type; Analyze MSFC's current methods for handling, storage, transport, and disposition of waste and surplussed materials; Determine the composition of various surplus and waste materials as to type and quantities from various sources and locations; Analyze different methods for the disposition of various surplus and waste materials, including quality, quantity, preparation, transport cost, and value; Study possible alternatives to current methods of handling, storage, transport, and disposition of surplus and waste materials to improve the quality and quantities recycled or sold and to reduce and minimize the quantities of surplus and waste material currently being disposed of or stored; Provide recommendations for source and centralized segregation and aggregation of materials for recycling and/or disposition; and The analysis could include identification and laboratory level evaluation of methods and/or equipment, including capital costs, operating costs, maintenance requirements, life cycle and return on investment for systems to support the waste reduction program mission.
Higher Education: A Developing Field of Study.
ERIC Educational Resources Information Center
Harcleroad, Fred F., Ed.
This volume includes materials that clearly indicate the state of the development of the field of higher education. The members of the Association of Professors of Higher Education gathered in their third formal national conference to read and discuss the materials included here. The ideas and information presented in this edited, and relatively…
Science Data Report for the Optical Properties Monitor (OPM) Experiment
NASA Technical Reports Server (NTRS)
Wilkes, Donald R.; Zwiener, James M.
1999-01-01
Long term stability of spacecraft materials when exposed to the space environment continues to be a major area of investigation. The natural and induced environment surrounding a spacecraft can decrease material performance and limit useful lifetimes. The Optical Properties Monitor (OPM) experiment provided the capability to perform the important flight testing of materials and was flown on the Russian Mir Station to study the long term effects of the natural and induced space environment on materials. The core of the OPM in-flight analysis was three independent optical instruments. These instruments included an integrating sphere spectral reflectometer, a vacuum ultraviolet spectrometer, and a Total Integrated Scatter instrument. The OPM also monitored selected components of the environment including molecular contamination. The OPM was exposed on the exterior of the Mir Docking Module for approximately 8-1/2 months. This report describes the OPM experiment, a brief background of its development, program organization, experiment description, mission overview including space environment definition, performance overview, materials data including flight and ground data, in-depth post flight analysis including ground analysis measurements and a summary discussion of the findings and results.
The value of materials R&D in the fast track development of fusion power
NASA Astrophysics Data System (ADS)
Ward, D. J.; Taylor, N. P.; Cook, I.
2007-08-01
The objective of the international fusion program is the creation of power plants with attractive safety and environmental features and viable economics. There is a range of possible plants that can meet these objectives, as studied for instance in the recent EU studies of power plant concepts. All of the concepts satisfy safety and environmental objectives but the economic performance is interpreted differently in different world regions according to the perception of future energy markets. This leads to different materials performance targets and the direction and timescales of the materials development programme needed to meet those targets. In this paper, the implications for materials requirements of a fast track approach to fusion development are investigated. This includes a quantification of the overall benefits of more advanced materials: including the effect of trading off an extended development time against a reduced cost of electricity for resulting power plants.
ERIC Educational Resources Information Center
Enfield, Mark; Smith, Edward L.; Grueber, David J.
2008-01-01
This research reports on a study of curriculum materials development and use compared with the use of existing curriculum materials in an elementary classroom. The research explored the effect of explicit attention to epistemic practices in curriculum materials and the enactment of those materials. Epistemic practices include asking questions,…
Anisotropy of machine building materials
NASA Technical Reports Server (NTRS)
Ashkenazi, Y. K.
1981-01-01
The results of experimental studies of the anisotropy of elastic and strength characteristics of various structural materials, including pressure worked metals and alloys, laminated fiberglass plastics, and laminated wood plastics, are correlated and classified. Strength criteria under simple and complex stresses are considered as applied to anisotropic materials. Practical application to determining the strength of machine parts and structural materials is discussed.
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2012 CFR
2012-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2011 CFR
2011-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2014 CFR
2014-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2010 CFR
2010-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2013 CFR
2013-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
The Speaker Respoken: Material Rhetoric as Feminist Methodology.
ERIC Educational Resources Information Center
Collins, Vicki Tolar
1999-01-01
Presents a methodology based on the concept of "material rhetoric" that can help scholars avoid problems as they reclaim women's historical texts. Defines material rhetoric and positions it theoretically in relation to other methodologies, including bibliographical studies, reception theory, and established feminist methodologies. Illustrates…
Research Resources for the Study of African-American and Jewish Relations.
ERIC Educational Resources Information Center
Gubert, Betty Kaplan
1994-01-01
Discusses New York City library resources for the study of African American and Jewish American relations. Highlights include library collections, access to materials, audio and visual materials, international newspapers, clippings, archives, children's books, and acquisitions. A list of the major libraries for the study of African American and…
ROSA, Wellington Luiz de Oliveira; SILVA, Tiago Machado; LIMA, Giana da Silveira; SILVA, Adriana Fernandes; PIVA, Evandro
2016-01-01
ABSTRACT Objective A systematic review was conducted to analyze Brazilian scientific and technological production related to the dental materials field over the past 50 years. Material and Methods This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (Prisma) statement. Searches were performed until December 2014 in six databases: MedLine (PubMed), Scopus, LILACS, IBECS, BBO, and the Cochrane Library. Additionally, the Brazilian patent database (INPI - Instituto Nacional de Propriedade Industrial) was screened in order to get an overview of Brazilian technological development in the dental materials field. Two reviewers independently analyzed the documents. Only studies and patents related to dental materials were included in this review. Data regarding the material category, dental specialty, number of documents and patents, filiation countries, and the number of citations were tabulated and analyzed in Microsoft Office Excel (Microsoft Corporation, Redmond, Washington, United States). Results A total of 115,806 studies and 53 patents were related to dental materials and were included in this review. Brazil had 8% affiliation in studies related to dental materials, and the majority of the papers published were related to dental implants (1,137 papers), synthetic resins (681 papers), dental cements (440 papers), dental alloys (392 papers) and dental adhesives (361 papers). The Brazilian technological development with patented dental materials was smaller than the scientific production. The most patented type of material was dental alloys (11 patents), followed by dental implants (8 patents) and composite resins (7 patents). Conclusions Dental materials science has had a substantial number of records, demonstrating an important presence in scientific and technological development of dentistry. In addition, it is important to approximate the relationship between academia and industry to expand the technological development in countries such as Brazil. PMID:27383712
Photoconductivity in Dirac materials
NASA Astrophysics Data System (ADS)
Shao, J. M.; Yang, G. W.
2015-11-01
Two-dimensional (2D) Dirac materials including graphene and the surface of a three-dimensional (3D) topological insulator, and 3D Dirac materials including 3D Dirac semimetal and Weyl semimetal have attracted great attention due to their linear Dirac nodes and exotic properties. Here, we use the Fermi's golden rule and Boltzmann equation within the relaxation time approximation to study and compare the photoconductivity of Dirac materials under different far- or mid-infrared irradiation. Theoretical results show that the photoconductivity exhibits the anisotropic property under the polarized irradiation, but the anisotropic strength is different between 2D and 3D Dirac materials. The photoconductivity depends strongly on the relaxation time for different scattering mechanism, just like the dark conductivity.
A study of 3-dimensionally periodic carbon nanostructures
NASA Astrophysics Data System (ADS)
Yin, Ming; Bleiweiss, Michael; Amirzadeh, Jafar; Datta, Timir; Arammash, Fouzi
2012-02-01
Electronic structures with intricate periodic 3-dimensional arrangements at the submicron scale were investigated. These may be fabricated using artificial porous opal substrates as the templates in which the targeted conducting medium is introduced. In the past these materials were reported to show interesting electronic behaviors. [Michael Bleiweiss, et al ``Localization and Related Phenomena in Multiply Connected Nanostructured,'' BAPS, Z30.011, Nanostructured Materials Session, March 2001, Seattle]. Several materials were studied in particular disordered carbon which has been reported to show quantum transport including fractional hall steps. The results of these measurements, including the observation of localization phenomena, will be discussed. Comparisons will be made with literature data.
Improved ablative materials for the ASRM nozzle
NASA Technical Reports Server (NTRS)
Canfield, A.; Clinton, R. G.; Armour, W.; Koenig, J.
1992-01-01
Rayon precursor carbon-cloth phenolic was developed more than 30 years ago and is used in most nozzles today including the Poseidon, Trident, Peacekeeper, Small ICBM, Space Shuttle, and numerous tactical and space systems. Specifications and manufacturing controls were placed on these materials and, once qualified, a no-change policy was instituted. The current material is acceptable; however, prepreg variability does not always accommodate the requirements of automation. The advanced solid rocket motor requires material with less variability for automated manufacturing. An advanced solid rocket motor materials team, composed of NASA, Thiokol, Aerojet, SRI, and Lockheed specialists, along with materials suppliers ICI Fiberite/Polycarbon, BP Chemicals/Hitco, and Amoco, embarked on a program to improve the current materials. The program consisted of heat treatment studies and standard and low-density material improvements evaluation. Improvements evaluated included fiber/fabric heat treatments, weave variations, resin application methods, process controls, and monitors.
ERIC Educational Resources Information Center
Kulich, Jindra, Comp.
This bibliography contains 682 listings covering English language materials on adult education in Europe published during 1980-82. Materials were chosen in accord with a broad definition of adult education that includes vocational education for adults; training in business and industry; adult secondary and postsecondary study; activities of…
Thermal protection system repair kit program
NASA Technical Reports Server (NTRS)
1979-01-01
The feasibility and conceptual design aspects of repair materials and procedures for in orbit repair of the space shuttle orbiter TPS tiles are investigated. Material studies to investigate cure in place materials are described including catalyst and cure studies, ablation tests and evaluations, and support mixing and applicator design. The feasibility of the repair procedures, the storage of the TPS, dispensing, and cure problems are addressed.
NASA Technical Reports Server (NTRS)
Bok, L. D.
1973-01-01
The study included material selection and trade-off for the structural components of the wheel and brake optimizing weight vs cost and feasibility for the space shuttle type application. Analytical methods were used to determine section thickness for various materials, and a table was constructed showing weight vs. cost trade-off. The wheel and brake were further optimized by considering design philosophies that deviate from standard aircraft specifications, and designs that best utilize the materials being considered.
Experiences with a New Shielding Material
NASA Astrophysics Data System (ADS)
Bücherl, T.; Calzada, E.; Liu, S. Q.; Stöwer, W.; Kortmann, F.; Größlhuber, H.; von Gostomski, Ch. Lierse
Recent modifications of the NECTAR facility included the set-up of a new beam dump. One of its main components is based on a reusable shielding material developed at TUM. The provided base material was characterized and its advantages and limitations were investigated by simulation studies and by measurements.
Diversified Cooperative Training. A Bibliography.
ERIC Educational Resources Information Center
Florida State Univ., Tallahassee. Center for Instructional Development and Services.
This bibliography describes 52 materials available for use in cooperative education classes and career and guidance counseling. The materials include books, pamphlets, and brochures, films, curriculum guides, study guides, and workbooks. A few are suited for use with special needs students. Materials for inclusion in the bibliography were located…
Home and Family Management. A Bibliography.
ERIC Educational Resources Information Center
Florida State Univ., Tallahassee. Center for Instructional Development and Services.
This bibliography describes 133 materials available for use in home economics classes. The materials include books, pamphlets and brochures, films curriculum guides, study guides, and workbooks. A few are suited for use with special needs students. Materials for inclusion in the bibliography were located through the Florida Educational Information…
Cases and Materials on Women and the Law for GS 200: Introduction to Women's Studies.
ERIC Educational Resources Information Center
Knowles, Marjorie Fine, Ed.
Cases and materials used in an undergraduate course, "Women and the Law," are divided to cover women and the Constitution of the U.S. (including the Equal Rights Amendment), the Supreme Court Abortion Decision, and the contemporary legal status of women including employment, education, and criminal law. Fifteen cases highlight the issues…
ERIC Educational Resources Information Center
Army Quartermaster School, Ft. Lee, VA.
This course, adapted from military curriculum materials for use in technical and vocational education, is of interest to food service personnel and to some food service supply personnel. Designed for independent study, the course includes the principles of nutrition, including nutrients and the effects of digestive processes on each individual's…
FIELD-SCALE STUDIES: HOW DOES SOIL SAMPLE PRETREATMENT AFFECT REPRESENTATIVENESS ? (ABSTRACT)
Samples from field-scale studies are very heterogeneous and can contain large soil and rock particles. Oversize materials are often removed before chemical analysis of the soil samples because it is not practical to include these materials. Is the extracted sample representativ...
FIELD-SCALE STUDIES: HOW DOES SOIL SAMPLE PRETREATMENT AFFECT REPRESENTATIVENESS?
Samples from field-scale studies are very heterogeneous and can contain large soil and rock particles. Oversize materials are often removed before chemical analysis of the soil samples because it is not practical to include these materials. Is the extracted sample representativ...
NASA Technical Reports Server (NTRS)
Anderson, G. R., II
1981-01-01
The feasibility of utilizing a sensitized pick to discriminate between cutting coal and roof material during the longwall mining process was investigated. A conventional longwall mining pick was instrumented and cutting force magnitudes were determined for a variety of materials, including Illinois #6 coal, shale type materials, and synthetic coal/shale materials.
Are patients comprehending? A critical assessment of online patient educational materials.
Bui, Thanh-Lan; Silva-Hirschberg, Catalina; Torres, Josefina; Armstrong, April W
2018-05-01
The primary aim of this study was to evaluate the readability, understandability, suitability and actionability of online psoriasis patient educational materials. A secondary aim was to identify areas for improvement. We conducted an evaluation study to assess online psoriasis patient educational materials from the American Academy of Dermatology and National Psoriasis Foundation available in July 2017. We used two validated assessment tools specific to online healthcare materials. Outcomes were expressed as percentages, where higher percentages corresponded to higher quality materials. Overall, the educational materials had a mean understandability score (72.7%) that was understandable; a suitability score (58.8%) that was adequate; a reading grade level (10.5) that was not readable; and an actionability score (54.7%) that was not actionable. Areas of improvement include reading grade level, visual aids, word choice, specific steps for actions and cultural appropriateness. Online psoriasis patient educational materials are understandable and suitable, but they are written above the American Medical Association and National Institutes of Health's recommended 6th-8th grade reading level and are not actionable. Materials can benefit from decreasing reading grade level, including more visual elements, incorporating more actionable items and being culturally inclusive.
Rosa, Wellington Luiz de Oliveira; Silva, Tiago Machado; Lima, Giana da Silveira; Silva, Adriana Fernandes; Piva, Evandro
2016-01-01
A systematic review was conducted to analyze Brazilian scientific and technological production related to the dental materials field over the past 50 years. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (Prisma) statement. Searches were performed until December 2014 in six databases: MedLine (PubMed), Scopus, LILACS, IBECS, BBO, and the Cochrane Library. Additionally, the Brazilian patent database (INPI - Instituto Nacional de Propriedade Industrial) was screened in order to get an overview of Brazilian technological development in the dental materials field. Two reviewers independently analyzed the documents. Only studies and patents related to dental materials were included in this review. Data regarding the material category, dental specialty, number of documents and patents, filiation countries, and the number of citations were tabulated and analyzed in Microsoft Office Excel (Microsoft Corporation, Redmond, Washington, United States). A total of 115,806 studies and 53 patents were related to dental materials and were included in this review. Brazil had 8% affiliation in studies related to dental materials, and the majority of the papers published were related to dental implants (1,137 papers), synthetic resins (681 papers), dental cements (440 papers), dental alloys (392 papers) and dental adhesives (361 papers). The Brazilian technological development with patented dental materials was smaller than the scientific production. The most patented type of material was dental alloys (11 patents), followed by dental implants (8 patents) and composite resins (7 patents). Dental materials science has had a substantial number of records, demonstrating an important presence in scientific and technological development of dentistry. In addition, it is important to approximate the relationship between academia and industry to expand the technological development in countries such as Brazil.
Bio-Contamination Control for Spacesuit Garments - A Preliminary Study
NASA Technical Reports Server (NTRS)
Rhodes, Richard; Korona, Adam; Orndoff, Evelyn; Ott, Mark; Poritz, Darwin
2010-01-01
This paper outlines a preliminary study to review, test, and improve upon the current state of spacesuit bio-contamination control. The study includes an evaluation of current and advanced suit materials, ground and on-orbit cleaning methods, and microbial test and analysis methods. The first aspect of this study was to identify potential anti-microbial textiles and cleaning agents, and to review current microbial test methods. The anti-microbial cleaning agent and textile market survey included a review of current commercial-off-the-shelf (COTS) products that could potentially be used as future space flight hardware. This review included replacements for any of the softgood layers that may become contaminated during an extravehicular activity (EVA), including the pressure bladder, liquid cooling garment, and ancillary comfort undergarment. After a series of COTS anti-microbial textiles and clean ing agents were identified, a series of four tests were conducted: (1) a stacked configuration test that was conducted in order to review how bio-contamination would propagate through the various suit layers, (2) a individual materials test that evaluated how well each softgood layer either promoted or repressed growth, (3) a cleaning agent test that evaluated the efficacy on each of the baseline bladders, and (4) an evaluation of various COTS anti-microbial textiles. All antimicrobial COTS materials tested appeared to control bacteria colony forming unit (CFU) growth better than the Thermal Comfort Undergarment (TCU) and ACES Liquid Cooling Garment (LCG)/EMU Liquid Cooling Ventilation Garment (LCVG) materials currently in use. However, a comparison of fungi CFU growth in COTS to current suit materials appeared to vary per material. All cleaning agents tested in this study appeared to inhibit the level of bacteria and fungi growth to acceptable levels for short duration tests. While several trends can be obtained from the current analysis, a series of test improvements are described for future microbial testing.
Sol-gel derived electrode materials for supercapacitor applications
NASA Astrophysics Data System (ADS)
Lin, Chuan
1998-12-01
Electrochemical capacitors have been receiving increasing interest in recent years for use in energy storage systems because of their high energy and power density and long cycle lifes. Possible applications of electrochemical capacitors include high power pulsed lasers, hybrid power system for electric vehicles, etc. In this dissertation, the preparation of electrode materials for use as electrochemical capacitors has been studied using the sol-gel process. The high surface area electrode materials explored in this work include a synthetic carbon xerogel for use in a double-layer capacitor, a cobalt oxide xerogel for use in a pseudocapacitor, and a carbon-ruthenium xerogel composite, which utilizes both double-layer and faradaic capacitances. The preparation conditions of these materials were investigated in detail to maximize the surface area and optimize the pore size so that more energy could be stored while minimizing mass transfer limitations. The microstructures of the materials were also correlated with their performance as electrochemical capacitors to improve their energy and power densities. Finally, an idealistic mathematical model, including both double-layer and faradaic processes, was developed and solved numerically. This model can be used to perform the parametric studies of an electrochemical capacitor so as to gain a better understanding of how the capacitor works and also how to improve cell operations and electrode materials design.
Synthesis and gas adsorption study of porous metal-organic framework materials
NASA Astrophysics Data System (ADS)
Mu, Bin
Metal-organic frameworks (MOFs) or porous coordination polymers (PCPs) have become the focus of intense study over the past decade due to their potential for advancing a variety of applications including air purification, gas storage, adsorption separations, catalysis, gas sensing, drug delivery, and so on. These materials have some distinct advantages over traditional porous materials such as the well-defined structures, uniform pore sizes, chemically functionalized sorption sites, and potential for postsynthetic modification, etc. Thus, synthesis and adsorption studies of porous MOFs have increased substantially in recent years. Among various prospective applications, air purification is one of the most immediate concerns, which has urgent requirements to improve current nuclear, biological, and chemical (NBC) filters involving commercial and military purposes. Thus, the major goal of this funded project is to search, synthesize, and test these novel hybrid porous materials for adsorptive removal of toxic industrial chemicals (TICs) and chemical warfare agents (CWAs), and to install the benchmark for new-generation NBC filters. The objective of this study is three-fold: (i) Advance our understanding of coordination chemistry by synthesizing novel MOFs and characterizing these porous coordination polymers; (ii) Evaluate porous MOF materials for gasadsorption applications including CO2 capture, CH4 storage, other light gas adsorption and separations, and examine the chemical and physical properties of these solid adsorbents including thermal stability and heat capacity of MOFs; (iii) Evaluate porous MOF materials for next-generation NBC filter media by adsorption breakthrough measurements of TICs on MOFs, and advance our understanding about structureproperty relationships of these novel adsorbents.
User-Defined Material Model for Progressive Failure Analysis
NASA Technical Reports Server (NTRS)
Knight, Norman F. Jr.; Reeder, James R. (Technical Monitor)
2006-01-01
An overview of different types of composite material system architectures and a brief review of progressive failure material modeling methods used for structural analysis including failure initiation and material degradation are presented. Different failure initiation criteria and material degradation models are described that define progressive failure formulations. These progressive failure formulations are implemented in a user-defined material model (or UMAT) for use with the ABAQUS/Standard1 nonlinear finite element analysis tool. The failure initiation criteria include the maximum stress criteria, maximum strain criteria, the Tsai-Wu failure polynomial, and the Hashin criteria. The material degradation model is based on the ply-discounting approach where the local material constitutive coefficients are degraded. Applications and extensions of the progressive failure analysis material model address two-dimensional plate and shell finite elements and three-dimensional solid finite elements. Implementation details and use of the UMAT subroutine are described in the present paper. Parametric studies for composite structures are discussed to illustrate the features of the progressive failure modeling methods that have been implemented.
Liquid Metals as Plasma-facing Materials for Fusion Energy Systems: From Atoms to Tokamaks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stone, Howard A.; Koel, Bruce E.; Bernasek, Steven L.
The objective of our studies was to advance our fundamental understanding of liquid metals as plasma-facing materials for fusion energy systems, with a broad scope: from atoms to tokamaks. The flow of liquid metals offers solutions to significant problems of the plasma-facing materials for fusion energy systems. Candidate metals include lithium, tin, gallium, and their eutectic combinations. However, such liquid metal solutions can only be designed efficiently if a range of scientific and engineering issues are resolved that require advances in fundamental fluid dynamics, materials science and surface science. In our research we investigated a range of significant and timelymore » problems relevant to current and proposed engineering designs for fusion reactors, including high-heat flux configurations that are being considered by leading fusion energy groups world-wide. Using experimental and theoretical tools spanning atomistic to continuum descriptions of liquid metals, and bridging surface chemistry, wetting/dewetting and flow, our research has advanced the science and engineering of fusion energy materials and systems. Specifically, we developed a combined experimental and theoretical program to investigate flows of liquid metals in fusion-relevant geometries, including equilibrium and stability of thin-film flows, e.g. wetting and dewetting, effects of electromagnetic and thermocapillary fields on liquid metal thin-film flows, and how chemical interactions and the properties of the surface are influenced by impurities and in turn affect the surface wetting characteristics, the surface tension, and its gradients. Because high-heat flux configurations produce evaporation and sputtering, which forces rearrangement of the liquid, and any dewetting exposes the substrate to damage from the plasma, our studies addressed such evaporatively driven liquid flows and measured and simulated properties of the different bulk phases and material interfaces. The range of our studies included (i) quantum mechanical calculations that allow inclusion of many thousands of atoms for the characterization of the interface of liquid metals exposed to continuous bombardment by deuterium and tritium as expected in fusion, (ii) molecular dynamics studies of the phase behavior of liquid metals, which (a) utilize thermodynamic properties computed using our quantum mechanical calculations and (b) establish material and wetting properties of the liquid metals, including relevant eutectics, (iii) experimental investigations of the surface science of liquid metals, interacting both with the solid substrate as well as gaseous species, and (iv) fluid dynamical studies that incorporate the material and surface science results of (ii) and (iii) in order to characterize flow in capillary porous materials and the thin-film flow along curved boundaries, both of which are potentially major components of plasma-facing materials. The outcome of these integrated studies was new understanding that enables developing design rules useful for future developments of the plasma-facing components critical to the success of fusion energy systems.« less
Spacecraft materials studies on the Aerospace Corporation tray on EOIM-3
NASA Technical Reports Server (NTRS)
Stuckey, Wayne K.; Hemminger, Carol S.; Steckel, Gary L.; Hills, Malina M.; Hilton, Michael R.
1995-01-01
A passive tray was flown on the Effects of Oxygen Interaction with Materials experiment on STS-46 (EOIM-3) with 82 samples from The Aerospace Corporation. A variety of advanced materials related to potential uses on future spacecraft were included for evaluation representing optical coatings, lubricants, polymers, composites, carbon-carbon composite protective coatings, graphite protective coatings, thermal-control materials, and some samples of current materials. An overview of the available results from the investigations of these materials is presented.
ERIC Educational Resources Information Center
MARTONFFY, ANDREA PONTECORVO; AND OTHERS
A CURRICULUM GUIDE ON MEDIEVAL STUDIES IS PRESENTED, INCLUDING TEACHER MATERIALS AND STUDENT PROBLEM SETS. THE TEACHER MATERIALS DESCRIBE AND EXPLAIN THE ECONOMIC, SOCIAL, AND POLITICAL ASPECTS OF MANORIAL LIFE--THE PREDOMINANT FORM OF AGRICULTURAL LIFE IN NORTHERN FRANCE, ENGLAND, AND GERMANY DURING THE PERIOD FROM APPROXIMATELY 800 TO 1300 A.D.…
Add Interest to Your Social Studies Curriculum without Cost.
ERIC Educational Resources Information Center
Bloom, Marion G.; And Others
1992-01-01
Lists a sampling of free materials and their sources for use by social studies teachers. Includes videos, maps, pamphlets, booklets, games, posters, and travel brochures from Norway, Saudi Arabia, Germany, and Korea among others. Provides source addresses, turnaround times, and descriptions of the materials. (DK)
Hill, B.R.; Hill, J.R.; Nolan, K.M.
1988-01-01
Data were collected during a 4-yr study of sediment sources in four drainage basins tributary to Lake Tahoe, California-Nevada. The study areas include the Blackwood, General, Edgewood, and Logan House Creek basins. Data include changes in bank and bed positions at channel cross sections; results of stream-channel mapping; analyses of bank and bed material samples; tabulations of bed material point counts; measured rates of hillslope erosion; dimensions of gullies; suspended-sediment data collected during synoptic snowmelt sampling; and physiographic data for the four study basins. (USGS)
Performance characterization of material identification systems
NASA Astrophysics Data System (ADS)
Brown, Christopher D.; Green, Robert L.
2006-10-01
In recent years a number of analytical devices have been proposed and marketed specifically to enable field-based material identification. Technologies reliant on mass, near- and mid-infrared, and Raman spectroscopies are available today, and other platforms are imminent. These systems tend to perform material recognition based on an on-board library of material signatures. While figures of merit for traditional quantitative analytical sensors are broadly established (e.g., SNR, selectivity, sensitivity, limit of detection/decision), measures of performance for material identification systems have not been systematically discussed. In this paper we present an approach to performance characterization similar in spirit to ROC curves, but including elements of precision-recall curves and specialized for the intended-use of material identification systems. Important experimental considerations are discussed, including study design, sources of bias, uncertainty estimation, and cross-validation and the approach as a whole is illustrated using a commercially available handheld Raman material identification system.
Factors Influencing Progressive Failure Analysis Predictions for Laminated Composite Structure
NASA Technical Reports Server (NTRS)
Knight, Norman F., Jr.
2008-01-01
Progressive failure material modeling methods used for structural analysis including failure initiation and material degradation are presented. Different failure initiation criteria and material degradation models are described that define progressive failure formulations. These progressive failure formulations are implemented in a user-defined material model for use with a nonlinear finite element analysis tool. The failure initiation criteria include the maximum stress criteria, maximum strain criteria, the Tsai-Wu failure polynomial, and the Hashin criteria. The material degradation model is based on the ply-discounting approach where the local material constitutive coefficients are degraded. Applications and extensions of the progressive failure analysis material model address two-dimensional plate and shell finite elements and three-dimensional solid finite elements. Implementation details are described in the present paper. Parametric studies for laminated composite structures are discussed to illustrate the features of the progressive failure modeling methods that have been implemented and to demonstrate their influence on progressive failure analysis predictions.
Each year EPA produces a report called Advancing Sustainable Materials Management: Facts and Figures. It includes information on municipal solid waste (MSW) generation, recycling, composting, combustion with energy recovery and landfilling. The 2014 report provides information on historical tipping fees for MSW, and information on the construction and demolition debris generation, which is outside of the scope of MSW. The Facts and Figures website includes recent reports (2012 to 2014 as well as historical information on materials in the U.S. Municipal Waste Stream, 1960 to 2014 (in tons). The reports for both current and historical waste prevention can be accessed at EPA's SMM website. The recent Annual Facts and Figures reports are accessible at the following link: https://www.epa.gov/smm/advancing-sustainable-materials-management-facts-and-figures-report. Historical data as well as studies and summary tables related to the Advancing Sustainable Materials Management Report are accessible here: https://www.epa.gov/smm/studies-summary-tables-and-data-related-advancing-sustainable-materials-management-report. An excel file containing the data from 1960 - 2014 is located here: https://edg.epa.gov/data/PUBLIC/OLEM/Materials_Municipal_Waste_Stream_1960_to_2014.xlsx. EPA also maintains a list of state and local waste characterization studies (reports are not available for all states). You can search for your state at https://www.epa.gov/smm/advancing-
include studies of surfaces and interfaces related to photovoltaic materials and devices as well as growth and characterization of novel photovoltaic materials such as Cu2ZnSnS4. Education B.S. Physics
Preparation for microgravity - The role of the Microgravity Material Science Laboratory
NASA Technical Reports Server (NTRS)
Johnston, J. Christopher; Rosenthal, Bruce N.; Meyer, Maryjo B.; Glasgow, Thomas K.
1988-01-01
Experiments at the NASA Lewis Research Center's Microgravity Material Science Laboratory using physical and mathematical models to delineate the effects of gravity on processes of scientific and commercial interest are discussed. Where possible, transparent model systems are used to visually track convection, settling, crystal growth, phase separation, agglomeration, vapor transport, diffusive flow, and polymer reactions. Materials studied include metals, alloys, salts, glasses, ceramics, and polymers. Specific technologies discussed include the General Purpose furnace used in the study of metals and crystal growth, the isothermal dendrite growth apparatus, the electromagnetic levitator/instrumented drop tube, the high temperature directional solidification furnace, the ceramics and polymer laboratories and the center's computing facilities.
Stainless Steel Corrosion Studies Final Report: FY17 End of-Year
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kelly, Daniel; Milenski, Helen Marie; Martinez, Destiny
Two materials are being considered in applications requiring their contact against stainless steel surfaces. These materials include the solvent methyl ethyl ketone (MEK), and the polymer neoprene (polychloroprene). There is concern that contact of these materials with stainless steel substrates may lead to corrosion. To address these concerns we have undertaken corrosion studies under conditions expected to be more aggressive than in intended applications. These conditions include elevated temperature and humidity, and submersion and suspension in solvent vapors, in an attempt to accelerate any potential deleterious interactions. Corrosion rates below 0.1 mpy have historically been deemed INSIGNIFICANT from a WRmore » Production standpoint; corresponding guidelines for non-production applications are lacking.« less
ERIC Educational Resources Information Center
San Diego City Schools, CA.
This newsletter is designed to promote the concept of bilingual-bicultural education. Included in this issue are articles on "Bilingual Education: Acceptance and Allocation,""A World History Reference,""History Teachers, Take Heart,""Social Studies Materials in Spanish," and "Pride of Aztlan." Articles appear in Spanish and English. Included is a…
Rollins, Harry W [Idaho Falls, ID; Petkovic, Lucia M [Idaho Falls, ID; Ginosar, Daniel M [Idaho Falls, ID
2011-02-01
Catalytic structures include a catalytic material disposed within a zeolite material. The catalytic material may be capable of catalyzing a formation of methanol from carbon monoxide and/or carbon dioxide, and the zeolite material may be capable of catalyzing a formation of hydrocarbon molecules from methanol. The catalytic material may include copper and zinc oxide. The zeolite material may include a first plurality of pores substantially defined by a crystal structure of the zeolite material and a second plurality of pores dispersed throughout the zeolite material. Systems for synthesizing hydrocarbon molecules also include catalytic structures. Methods for synthesizing hydrocarbon molecules include contacting hydrogen and at least one of carbon monoxide and carbon dioxide with such catalytic structures. Catalytic structures are fabricated by forming a zeolite material at least partially around a template structure, removing the template structure, and introducing a catalytic material into the zeolite material.
Lectures and Simulation Laboratories to Improve Learners' Conceptual Understanding
ERIC Educational Resources Information Center
Brophy, Sean P.; Magana, Alejandra J.; Strachan, Alejandro
2013-01-01
We studied the use of online molecular dynamics simulations (MD) to enhance student abilities to understand the atomic processes governing plastic deformation in materials. The target population included a second-year undergraduate engineering course in the School of Materials Engineering at Purdue University. The objectives of the study were to…
Case studies in conservation science
NASA Astrophysics Data System (ADS)
Bisulca, Christina
The research presented in this dissertation covers three separate topics of conservation as defined by the National Science Foundation: 1) Materials Stabilization, Strengthening, Monitoring, and Repair; 2. Understanding Material Degradation and Aging; and 3) Materials and Structural Characterization of Cultural Heritage Objects (the 'technical study'). The first topic is addressed through a study to assess the consolidant tetraethoxysilane for the stabilization of alum treated wood. Falling under materials degradation studies is a study published in American Museum Novitates to understand how environmental conditions affect the aging of fossil resins from five different deposits. Two separate studies are included in technical study of cultural heritage objects which comprises the third research area of materials characterization. The first is a survey of red dyes used in Chinese paintings from the Ming Dynasty to the Early Republic (1364-1911). The second is a study of the pigments, dyes and binders used in Hawaiian barkcloth (kapa) from the 19th century.
Investigation of test methods, material properties, and processes for solar cell encapsulants
NASA Technical Reports Server (NTRS)
Willis, P. B.
1983-01-01
A study of potentially useful low cost encapsulation materials for the Flat-Plate Solar Array project is discussed. The goal is to identify, evaluate, test and recommend encapsulant materials and processes for the production of cost-effective, long life solar cell modules. Technical investigations included studies of aging and degradation of candidate encapsulation materials, continued identification of primers for durable bonding of module interfaces, continued evaluation of soil resistant treatments for the sunlit surface of the module and testing of corrosion protective coatings for use low cost mild steel substrates.
2007-09-01
is necessary to convert the solids to a 3-D computational mesh. The user must decide how many layers of mesh elements are required for each material ...together to define the geology gives the user more control over the material contacts. Secondly, the tool to convert directly to a 3-D mesh from the...included in the model. Rocks, cracks , fissures, and plant material can affect the flow character- istics, but cannot be included in a model on this scale
Black History: African Heritage, American Heritage.
ERIC Educational Resources Information Center
Duea, Joan; And Others
Providing elementary school teachers with materials to enhance student awareness of black heritage is the goal of this unit. Each of the 10 lessons includes objectives, materials, and procedures as well as supplementary materials that may be duplicated for student use. The land and people of Africa are studied in lessons one through three. Games,…
Censorship of Sexual Materials: A Selected, Annotated Basic Bibliography.
ERIC Educational Resources Information Center
Tedford, Thomas L.
The 37 references in this annotated bibliography are compiled for researchers of information on the censorship of sexual materials from ancient times to present. The materials include case studies, histories, essays, and opinion pieces about the use and regulation of "obscenity" in literature, pictorial art, radio broadcasting, the mail, film, and…
In Search of Canadian Materials, Revised.
ERIC Educational Resources Information Center
Phillips, Donna, Comp.
Designed as an aid to the selection of Canadian materials for the school library, this revised edition lists 2,100 titles and provides a new separate section on women's studies. Major subdivisions of the work include periodical and reference materials sections, as well as sections by subject category: business and consumer education; fine arts,…
Synthesis: Part I, Buildability.
ERIC Educational Resources Information Center
Pressman, Rob
This unit is designed to show the student how to pull together information on natural and man-managed systems to develop a coherent and environmentally sound plan of action. The material includes student guide sheets, reference material, and a tape script. Audiotapes are usually used with the materials. The unit assumes the student has studied a…
Toward the Development of a Model to Estimate the Readability of Credentialing-Examination Materials
ERIC Educational Resources Information Center
Badgett, Barbara A.
2010-01-01
The purpose of this study was to develop a set of procedures to establish readability, including an equation, that accommodates the multiple-choice item format and occupational-specific language related to credentialing examinations. The procedures and equation should be appropriate for learning materials, examination materials, and occupational…
HERO HELPS for Home Economics Related Occupation Coordinators. Volume II.
ERIC Educational Resources Information Center
Northern Arizona Univ., Flagstaff. Center for Vocational Education.
These 26 modules for independent study comprise the second volume of a two-volume set of HERO (Home Economics Related Occupations) HELPS for student use in competency-based professional development. Each module contains teacher and student materials. Teacher materials include an information sheet listing resources and materials needed by students,…
Teaching American Diplomacy Using Primary Sources: Cuba
ERIC Educational Resources Information Center
Kraft, Michael; Anderson, David J.; Starbird, Caroline; Ertenberg, Samantha
2005-01-01
The purpose of this book is to allow high school students to examine the relationship between Cuba and the United States by studying a rich collection of primary materials and classroom-ready lessons which incorporate those materials. This book contains materials from 27 primary sources, including texts of speeches before the House and Senate,…
Instructional Materials in Spanish for Agriculture. Final Report.
ERIC Educational Resources Information Center
Mainous, Bruce H.
A federally funded project to develop Spanish for Agricultural Purposes, a set of instructional materials for agricultural specialists planning to work in Latin America, is reported. The materials are intended for use by individuals with at least a year's college-level study of Spanish. They include: a series of authentic readings, each with an…
Educative Curriculum Materials: Uptake, Impact, and Implications for Research and Design
ERIC Educational Resources Information Center
Davis, Elizabeth A.; Palincsar, Annemarie Sullivan; Smith, P. Sean; Arias, Anna Maria; Kademian, Sylvie M.
2017-01-01
The authors synthesize the findings of a research project to extend what is known about educative curriculum materials, or curriculum materials designed with the intent of supporting teacher learning as well as student learning. Drawing on a three-year program of research, including several close observational case studies and a large-scale…
MULTI-MEDIA CATALOG OF THE INSTRUCTIONAL MATERIALS CENTER.
ERIC Educational Resources Information Center
Saginaw County Intermediate School District, MI.
THIS IS A LISTING OF MATERIALS FOR K-12 AVAILABLE FOR TEACHERS AND PLANNERS, INCLUDING FILM LOOPS, TAPE RECORDINGS, FILMSTRIPS, SLIDES, TRANSPARENCIES, RECORDS, STUDY AND ART PRINTS, MODELS AND REALIA, SCULPTURE AND KITS. AN OVERALL SUBJECT INDEX IS FOLLOWED BY SEPARATE SUBJECT LISTS FOR EACH TYPE OF MATERIAL. A BRIEF DESCRIPTION OF EACH…
Adaptation of Instructional Materials for Use with Mainstreamed Students. Final Report.
ERIC Educational Resources Information Center
Macro Systems, Inc., Silver Spring, MD.
The report documents a project to adapt and design instructional media and materials of a regular senior high social studies curriculum for use with mainstreamed mildly handicapped students. Supplementary materials were developed and tested at five sites to accompany the world history textbook, "Our Common Heritage." Products included the…
SELF-INSTRUCTIONAL SUPPLEMENTS FOR A TELEVISED PHYSICS COURSE, STUDY PLAN AND EXPERIMENTAL DESIGN.
ERIC Educational Resources Information Center
KLAUS, DAVID J.; LUMSDAINE, ARTHUR A.
THE INITIAL PHASES OF A STUDY OF SELF-INSTRUCTIONAL AIDS FOR A TELEVISED PHYSICS COURSE WERE DESCRIBED. THE APPROACH, EXPERIMENTAL DESIGN, PROCEDURE, AND TECHNICAL ASPECTS OF THE STUDY PLAN WERE INCLUDED. THE MATERIALS WERE PREPARED TO SUPPLEMENT THE SECOND SEMESTER OF HIGH SCHOOL PHYSICS. THE MATERIAL COVERED STATIC AND CURRENT ELECTRICITY,…
Study to develop improved fire resistant aircraft passenger seat materials, phase 1
NASA Technical Reports Server (NTRS)
Trabold, E. L.
1977-01-01
The procurement and testing of a wide range of candidate materials is reported. Improved fire resistant nonmetallic materials were subjected to tests to evaluate their thermal characteristics, such as burn, smoke generation, heat release rate and toxicity. In addition, candidate materials were evaluated for mechanical, physical and aesthetic properties. Other properties considered included safety, comfort, durability and maintainability. The fiscal year 1977 and the projected 1980 cost data were obtained for aircraft seat materials.
Rolllins, Harry W [Idaho Falls, ID; Petkovic, Lucia M [Idaho Falls, ID; Ginosar, Daniel M [Idaho Falls, ID
2012-07-24
Catalytic structures include a catalytic material disposed within a zeolite material. The catalytic material may be capable of catalyzing a formation of methanol from carbon monoxide and/or carbon dioxide, and the zeolite material may be capable of catalyzing a formation of hydrocarbon molecules from methanol. The catalytic material may include copper and zinc oxide. The zeolite material may include a first plurality of pores substantially defined by a crystal structure of the zeolite material and a second plurality of pores dispersed throughout the zeolite material. Systems for synthesizing hydrocarbon molecules also include catalytic structures. Methods for synthesizing hydrocarbon molecules include contacting hydrogen and at least one of carbon monoxide and carbon dioxide with such catalytic structures. Catalytic structures are fabricated by forming a zeolite material at least partially around a template structure, removing the template structure, and introducing a catalytic material into the zeolite material.
Computational materials design of crystalline solids.
Butler, Keith T; Frost, Jarvist M; Skelton, Jonathan M; Svane, Katrine L; Walsh, Aron
2016-11-07
The modelling of materials properties and processes from first principles is becoming sufficiently accurate as to facilitate the design and testing of new systems in silico. Computational materials science is both valuable and increasingly necessary for developing novel functional materials and composites that meet the requirements of next-generation technology. A range of simulation techniques are being developed and applied to problems related to materials for energy generation, storage and conversion including solar cells, nuclear reactors, batteries, fuel cells, and catalytic systems. Such techniques may combine crystal-structure prediction (global optimisation), data mining (materials informatics) and high-throughput screening with elements of machine learning. We explore the development process associated with computational materials design, from setting the requirements and descriptors to the development and testing of new materials. As a case study, we critically review progress in the fields of thermoelectrics and photovoltaics, including the simulation of lattice thermal conductivity and the search for Pb-free hybrid halide perovskites. Finally, a number of universal chemical-design principles are advanced.
Preliminary findings of the LDEF Materials Special Investigation Group
NASA Technical Reports Server (NTRS)
Stein, Bland A.; Pippin, H. Gary
1992-01-01
The retrieval of NASA's LDEF from low Earth orbit provided an opportunity for the study of long duration space environmental effects on materials. The five year, nine month flight of the LDEF greatly enhanced the potential value of most LDEF materials. NASA recognized this potential by forming the LDEF Space Environmental Effects on Materials Special Investigation Group (MSIG). Its goal is to explore the expanded materials analysis opportunities available in the LDEF structure and on experiment trays. The charter and scope of MSIG activities is presented, followed by an overview of the preliminary MSIG observations. These observations of low Earth orbit environmental effects on materials were made in-space during LDEF retrieval and during LDEF tray disintegration. Also presented are initial findings of lab analyses of LDEF materials. Included are effects of individual environmental parameters: atomic oxygen, ultraviolet radiation, meteoroid and debris impacts, thermal cycling, vacuum, and contamination, plus combined effects of these parameters. Materials considered include anodized aluminum, polymer matrix composites, polymer films, silvered Teflon thermal blankets, and a white thermal control paint.
Rare earth-doped materials with enhanced thermoelectric figure of merit
DOE Office of Scientific and Technical Information (OSTI.GOV)
Venkatasubramanian, Rama; Cook, Bruce Allen; Levin, Evgenii M.
A thermoelectric material and a thermoelectric converter using this material. The thermoelectric material has a first component including a semiconductor material and a second component including a rare earth material included in the first component to thereby increase a figure of merit of a composite of the semiconductor material and the rare earth material relative to a figure of merit of the semiconductor material. The thermoelectric converter has a p-type thermoelectric material and a n-type thermoelectric material. At least one of the p-type thermoelectric material and the n-type thermoelectric material includes a rare earth material in at least one ofmore » the p-type thermoelectric material or the n-type thermoelectric material.« less
Phinney, Karen W; Sempos, Christopher T; Tai, Susan S-C; Camara, Johanna E; Wise, Stephen A; Eckfeldt, John H; Hoofnagle, Andrew N; Carter, Graham D; Jones, Julia; Myers, Gary L; Durazo-Arvizu, Ramon; Miller, W Greg; Bachmann, Lorin M; Young, Ian S; Pettit, Juanita; Caldwell, Grahame; Liu, Andrew; Brooks, Stephen P J; Sarafin, Kurtis; Thamm, Michael; Mensink, Gert B M; Busch, Markus; Rabenberg, Martina; Cashman, Kevin D; Kiely, Mairead; Galvin, Karen; Zhang, Joy Y; Kinsella, Michael; Oh, Kyungwon; Lee, Sun-Wha; Jung, Chae L; Cox, Lorna; Goldberg, Gail; Guberg, Kate; Meadows, Sarah; Prentice, Ann; Tian, Lu; Brannon, Patsy M; Lucas, Robyn M; Crump, Peter M; Cavalier, Etienne; Merkel, Joyce; Betz, Joseph M
2017-09-01
The Vitamin D Standardization Program (VDSP) coordinated a study in 2012 to assess the commutability of reference materials and proficiency testing/external quality assurance materials for total 25-hydroxyvitamin D [25(OH)D] in human serum, the primary indicator of vitamin D status. A set of 50 single-donor serum samples as well as 17 reference and proficiency testing/external quality assessment materials were analyzed by participating laboratories that used either immunoassay or LC-MS methods for total 25(OH)D. The commutability test materials included National Institute of Standards and Technology Standard Reference Material 972a Vitamin D Metabolites in Human Serum as well as materials from the College of American Pathologists and the Vitamin D External Quality Assessment Scheme. Study protocols and data analysis procedures were in accordance with Clinical and Laboratory Standards Institute guidelines. The majority of the test materials were found to be commutable with the methods used in this commutability study. These results provide guidance for laboratories needing to choose appropriate reference materials and select proficiency or external quality assessment programs and will serve as a foundation for additional VDSP studies.
Materials technology for Stirling space power converters
NASA Technical Reports Server (NTRS)
Baggenstoss, William; Mittendorf, Donald
1992-01-01
This program was conducted in support of the NASA LeRC development of the Stirling power converter (SPC) for space power applications. The objectives of this contract were: (1) to perform a technology review and analyses to support the evaluation of materials issues for the SPC; (2) to evaluate liquid metal compatibility issues of the SPC; (3) to evaluate and define a transient liquid phase diffusion bonding (TLPDB) process for the SPC joints to the Udimet 720 heater head; and (4) to evaluate alternative (to the TLPDB) joining techniques. In the technology review, several aspects of the current Stirling design were examined including the power converter assembly process, materials joining, gas bearings, and heat exchangers. The supporting analyses included GLIMPS power converter simulation in support of the materials studies, and system level analysis in support of the technology review. The liquid metal compatibility study evaluated process parameters for use in the Stirling power converter. The alternative joining techniques study looked at the applicability of various joining techniques to the Stirling power converter requirements.
Post-impact alteration of the Manson impact structure
NASA Technical Reports Server (NTRS)
Crossey, L. J.; Mccarville, P.
1993-01-01
Core materials from the Manson impact site (Manson, Iowa) are examined in order to evaluate post-impact alteration processes. Diagenetic interpretation of post-impact events is based on petrologic, mineralogic, and geochemical investigation of core materials including the following: target strata, disturbed and disrupted strata, ejecta, breccias, microbreccias, and impact melt. The diagenetic study utilizes research cores obtained by the continental scientific drilling project (CSDP) at the Manson structure, as well as core and cuttings of related materials. Samples include impactites (breccias, microbreccias, and melt material), crater fill material (sedimentary clast breccias), disturbed and disrupted target rocks, and reference target material (Amoco Eisheid No. 1 materials). The study of multiple cores will permit development of a regional picture of post-impact thermal history. The specific objectives are as follows: (1) provide a detailed description of authigenic and alteration mineralogy from diverse lithologies encountered in research drill cores at the Manson impact structure, and (2) identify and relate significant post-impact mineral alteration to post-impact thermal regime (extent and duration). Results will provide mineralogical and geochemical constraints on models for post-impact processes including the following: infilling of the crater depression; cooling and hydrothermal alteration of melt rocks; and subsequent long-term, low-temperature alteration of target rocks, breccias, and melt rocks. Preliminary petrologic and x-ray diffraction examination of fracture linings and void fillings from research core M1 indicate the presence of quartz, chlorite, mixed-layer clays, gypsum/anhydrite, calcite, and minor pyrite.
Composite structural materials
NASA Technical Reports Server (NTRS)
Ansell, G. S.; Loewy, R. G.; Wiberley, S. E.
1984-01-01
Progress is reported in studies of constituent materials composite materials, generic structural elements, processing science technology, and maintaining long-term structural integrity. Topics discussed include: mechanical properties of high performance carbon fibers; fatigue in composite materials; experimental and theoretical studies of moisture and temperature effects on the mechanical properties of graphite-epoxy laminates and neat resins; numerical investigations of the micromechanics of composite fracture; delamination failures of composite laminates; effect of notch size on composite laminates; improved beam theory for anisotropic materials; variation of resin properties through the thickness of cured samples; numerical analysis composite processing; heat treatment of metal matrix composites, and the RP-1 and RP2 gliders of the sailplane project.
Shelf life studies of common hazardous materials: An innovative approach to pollution prevention
DOE Office of Scientific and Technical Information (OSTI.GOV)
Farmanian, P.A.
1995-12-31
Hazardous chemical systems, ranging in form from simple materials to compounded products and complex natural mixtures, constitute an important asset in the Navy`s daily operations. These materials include but are not limited to paints, solvents, soaps, resins, adhesives, pesticides, printing materials, petroleum products, and photographic chemicals. The short-lived availability of hazardous materials that are suspected of or known to degrade over time imposes a unique burden on the Navy`s procurement and hazardous waste disposal systems. Hazardous Materials whose shelf life`s have expired are processed for disposal as hazardous wastes. In addition, these expired hazardous materials must be replaced with newmore » materials. Many shelf life codes are based solely on the recommendations of suppliers and are not critically subjected to scientific study. The important goal of this project is to conduct a comprehensive study of the degradation of a given hazardous material to determine the true shelf life.« less
Energy harvesting: an integrated view of materials, devices and applications.
Radousky, H B; Liang, H
2012-12-21
Energy harvesting refers to the set of processes by which useful energy is captured from waste, environmental, or mechanical sources and is converted into a usable form. The discipline of energy harvesting is a broad topic that includes established methods and materials such as photovoltaics and thermoelectrics, as well as more recent technologies that convert mechanical energy, magnetic energy and waste heat to electricity. This article will review various state-of-the-art materials and devices for direct energy conversion and in particular will include multistep energy conversion approaches. The article will highlight the nano-materials science underlying energy harvesting principles and devices, but also include more traditional bulk processes and devices as appropriate and synergistic. Emphasis is placed on device-design innovations that lead to higher efficiency energy harvesting or conversion technologies ranging from the cm/mm-scale down to MEMS/NEMS (micro- and nano-electromechanical systems) devices. Theoretical studies are reviewed, which address transport properties, crystal chemistry, thermodynamic analysis, energy transfer, system efficiency and device operation. New developments in experimental methods; device design and fabrication; nanostructured materials fabrication; materials properties; and device performance measurement techniques are discussed.
Energy harvesting: an integrated view of materials, devices and applications
NASA Astrophysics Data System (ADS)
Radousky, H. B.; Liang, H.
2012-12-01
Energy harvesting refers to the set of processes by which useful energy is captured from waste, environmental, or mechanical sources and is converted into a usable form. The discipline of energy harvesting is a broad topic that includes established methods and materials such as photovoltaics and thermoelectrics, as well as more recent technologies that convert mechanical energy, magnetic energy and waste heat to electricity. This article will review various state-of-the-art materials and devices for direct energy conversion and in particular will include multistep energy conversion approaches. The article will highlight the nano-materials science underlying energy harvesting principles and devices, but also include more traditional bulk processes and devices as appropriate and synergistic. Emphasis is placed on device-design innovations that lead to higher efficiency energy harvesting or conversion technologies ranging from the cm/mm-scale down to MEMS/NEMS (micro- and nano-electromechanical systems) devices. Theoretical studies are reviewed, which address transport properties, crystal chemistry, thermodynamic analysis, energy transfer, system efficiency and device operation. New developments in experimental methods; device design and fabrication; nanostructured materials fabrication; materials properties; and device performance measurement techniques are discussed.
NASA Astrophysics Data System (ADS)
Xuan, Yue
Background. Soft materials such as polymers and soft tissues have diverse applications in bioengineering, medical care, and industry. Quantitative mechanical characterization of soft materials at multiscales is required to assure that appropriate mechanical properties are presented to support the normal material function. Indentation test has been widely used to characterize soft material. However, the measurement of in situ contact area is always difficult. Method of Approach. A transparent indenter method was introduced to characterize the nonlinear behaviors of soft materials under large deformation. This approach made the direct measurement of contact area and local deformation possible. A microscope was used to capture the contact area evolution as well as the surface deformation. Based on this transparent indenter method, a novel transparent indentation measurement systems has been built and multiple soft materials including polymers and pericardial tissue have been characterized. Seven different indenters have been used to study the strain distribution on the contact surface, inner layer and vertical layer. Finite element models have been built to simulate the hyperelastic and anisotropic material behaviors. Proper material constants were obtained by fitting the experimental results. Results.Homogeneous and anisotropic silicone rubber and porcine pericardial tissue have been examined. Contact area and local deformation were measured by real time imaging the contact interface. The experimental results were compared with the predictions from the Hertzian equations. The accurate measurement of contact area results in more reliable Young's modulus, which is critical for soft materials. For the fiber reinforced anisotropic silicone rubber, the projected contact area under a hemispherical indenter exhibited elliptical shape. The local surface deformation under indenter was mapped using digital image correlation program. Punch test has been applied to thin films of silicone rubber and porcine pericardial tissue and results were analyzed using the same method. Conclusions. The transparent indenter testing system can effectively reduce the material properties measurement error by directly measuring the contact radii. The contact shape can provide valuable information for the anisotropic property of the material. Local surface deformation including contact surface, inner layer and vertical plane can be accurately tracked and mapped to study the strain distribution. The potential usage of the transparent indenter measurement system to investigate biological and biomaterials was verified. The experimental data including the real-time contact area combined with the finite element simulation would be powerful tool to study mechanical properties of soft materials and their relation to microstructure, which has potential in pathologies study such as tissue repair and surgery plan. Key words: transparent indenter, large deformation, soft material, anisotropic.
Chemical vapor deposition growth
NASA Technical Reports Server (NTRS)
Ruth, R. P.; Manasevit, H. M.; Kenty, J. L.; Moudy, L. A.; Simpson, W. I.; Yang, J. J.
1976-01-01
The chemical vapor deposition (CVD) method for the growth of Si sheet on inexpensive substrate materials is investigated. The objective is to develop CVD techniques for producing large areas of Si sheet on inexpensive substrate materials, with sheet properties suitable for fabricating solar cells meeting the technical goals of the Low Cost Silicon Solar Array Project. Specific areas covered include: (1) modification and test of existing CVD reactor system; (2) identification and/or development of suitable inexpensive substrate materials; (3) experimental investigation of CVD process parameters using various candidate substrate materials; (4) preparation of Si sheet samples for various special studies, including solar cell fabrication; (5) evaluation of the properties of the Si sheet material produced by the CVD process; and (6) fabrication and evaluation of experimental solar cell structures, using standard and near-standard processing techniques.
ERIC Educational Resources Information Center
Memming, Agnes K.; And Others
This teacher's guide, for use in a fifth-grade German course, contains 12 units of instructional materials which concentrate on the development of basic audiolingual skills. Each of the units consists of conversational skits, dialogue adaptation, directed dialogue review, and classroom drills. Units include: (1) Das Aufstehen und das Fruhstuck,…
Development of a test and flight engineering oriented language. Phase 3: Presentation
NASA Technical Reports Server (NTRS)
Kamsler, W. F.; Case, C. W.; Kinney, E. L.; Gyure, J.
1970-01-01
The format material used in an oral presentation of the phase 3 study effort is given. The material includes a description of the language ALOFT and a terminology comparison with other test languages.
Hill, B.R.; Hill, J.R.; Nolan, K.M.
1990-01-01
Data were collected during a 5-year study of sediment sources in four drainage basins tributary to Lake Tahoe, California-Nevada. The study areas include the Blackwood Creek, General Creek, Edgewood Creek, and Logan House Creek basins. Data include changes in bank and bed positions at channel cross sections; results of stream-channel inventories; analyses of bank and bed material samples; tabulations of bed-material pebble counts; measured rates of hillslope erosion; dimensions of gullies; suspended-sediment data collected during synoptic snowmelt sampling; and physiographic data for the four study basins. (USGS)
Investigation of contact allergy to dental materials by patch testing.
Rai, Reena; Dinakar, Devina; Kurian, Swetha S; Bindoo, Y A
2014-07-01
Dental products are widely used by patients and dental personnel alike and may cause problems for both. Dental materials could cause contact allergy with varying manifestations such as burning, pain, stomatitis, cheilitis, ulcers, lichenoid reactions localized to the oral mucosa in patients, and hand dermatitis in dental personnel. Patch testing with the dental series comprising commonly used materials can be used to detect contact allergies to dental materials. This study aimed to identify contact allergy among patients who have oral mucosal lesions after dental treatment and among dental personnel who came in contact with these materials. Twenty patients who had undergone dental procedures with symptoms of oral lichen planus, oral stomatitis, burning mouth, and recurrent aphthosis, were included in the study. Dental personnel with history of hand dermatitis were also included in the study. Patch testing was performed using Chemotechnique Dental Series and results interpreted as recommended by the International Contact Dermatitis Research Group (ICDRG). Out of 13 patients who had undergone dental treatment/with oral symptoms, six patients with stomatitis, lichenoid lesions, and oral ulcers showed positive patch tests to a variety of dental materials, seven patients with ulcers had negative patch tests, seven dental personnel with hand dermatitis showed multiple allergies to various dental materials, and most had multiple positivities. The patch test is a useful, simple, noninvasive method to detect contact allergies among patients and among dental personnel dealing with these products. Long term studies are necessary to establish the relevance of these positive patch tests by eliminating the allergic substances, identifying clinical improvement, and substituting with nonallergenic materials.
Investigation of contact allergy to dental materials by patch testing
Rai, Reena; Dinakar, Devina; Kurian, Swetha S.; Bindoo, Y. A.
2014-01-01
Background: Dental products are widely used by patients and dental personnel alike and may cause problems for both. Dental materials could cause contact allergy with varying manifestations such as burning, pain, stomatitis, cheilitis, ulcers, lichenoid reactions localized to the oral mucosa in patients, and hand dermatitis in dental personnel. Patch testing with the dental series comprising commonly used materials can be used to detect contact allergies to dental materials. Aim: This study aimed to identify contact allergy among patients who have oral mucosal lesions after dental treatment and among dental personnel who came in contact with these materials. Materials and Methods: Twenty patients who had undergone dental procedures with symptoms of oral lichen planus, oral stomatitis, burning mouth, and recurrent aphthosis, were included in the study. Dental personnel with history of hand dermatitis were also included in the study. Patch testing was performed using Chemotechnique Dental Series and results interpreted as recommended by the International Contact Dermatitis Research Group (ICDRG). Results: Out of 13 patients who had undergone dental treatment/with oral symptoms, six patients with stomatitis, lichenoid lesions, and oral ulcers showed positive patch tests to a variety of dental materials, seven patients with ulcers had negative patch tests, seven dental personnel with hand dermatitis showed multiple allergies to various dental materials, and most had multiple positivities. Conclusion: The patch test is a useful, simple, noninvasive method to detect contact allergies among patients and among dental personnel dealing with these products. Long term studies are necessary to establish the relevance of these positive patch tests by eliminating the allergic substances, identifying clinical improvement, and substituting with nonallergenic materials. PMID:25165644
NASA Technical Reports Server (NTRS)
Misra, Ajay K.
1990-01-01
Aluminide-base intermetallic matrix composites are currently being considered as potential high-temperature materials. One of the key factors in the selection of a reinforcement material is its chemical stability in the matrix. In this study, chemical interactions between iron aluminides and several potential reinforcement materials, which include carbides, oxides, borides, and nitrides, are analyzed from thermodynamic considerations. Several chemically compatible reinforcement materials are identified for the iron aluminides with Al concentrations ranging from 40 to 50 at. pct.
ERIC Educational Resources Information Center
Housmam, John L.; And Others
The instructor's guide is coordinated for use with the student guide. The guide includes suggestions for teacher preparation, equipment and supply needs, suggested references, available audiovisual materials, open-ended questions for classroom discussion, educational opportunities for students, and a form for student evaluation of the study guide.…
NASA Astrophysics Data System (ADS)
Widhitama, Y. N.; Lukito, A.; Khabibah, S.
2018-01-01
The aim of this research is to develop problem solving based learning materials on fraction for training creativity of elementary school students. Curriculum 2006 states that mathematics should be studied by all learners starting from elementary level in order for them mastering thinking skills, one of them is creative thinking. To our current knowledge, there is no such a research topic being done. To promote this direction, we initiate by developing learning materials with problem solving approach. The developed materials include Lesson Plan, Student Activity Sheet, Mathematical Creativity Test, and Achievement Test. We implemented a slightly modified 4-D model by Thiagajan et al. (1974) consisting of Define, Design, Development, and Disseminate. Techniques of gathering data include observation, test, and questionnaire. We applied three good qualities for the resulted materials; that is, validity, practicality, and effectiveness. The results show that the four mentioned materials meet the corresponding criteria of good quality product.
An Integrated, Problem-Based Learning Material: The "Satellite" Module
ERIC Educational Resources Information Center
Selcuk, Gamze Sezgin; Emiroglu, Handan Byacioglu; Tarakci, Mehmet; Ozel, Mustafa
2011-01-01
The purpose of this study is to introduce a problem-based learning material, the Satellite Module, that has integrated some of the subjects included in the disciplines of physics and mathematics at an introductory level in undergraduate education. The reason why this modular and problem-based material has been developed is to enable students to…
Earth Day in the Classroom: Mathematics and Science Materials and Resources for Teachers.
ERIC Educational Resources Information Center
Crow, Tracy, Ed.
1995-01-01
The 25th anniversary of Earth Day is 1995. This issue highlights useful, high quality educational materials and other resources that can be used to discuss environmental issues in the classroom. Activities, resources, and teaching materials in this Earth Day issue include: ATLAS 1: Studying Mysteries in the Earth's Atmosphere; Completing the…
Reflections on Visual and Material Culture: An Example from Southwest Chicago
ERIC Educational Resources Information Center
Ulbricht, J.
2007-01-01
Although several art educators have called our attention to the importance of studying visual culture, others have widened the discussion to include material culture and its effects on our lives. Because of growing concern for the value of exploring the personal and social functions of visual and material culture, the purpose of this article is to…
Hairy carbon electrodes studied by cyclic voltammetry and battery discharge testing
NASA Technical Reports Server (NTRS)
Chung, Deborah D. L.; Shui, Xiaoping; Frysz, Christine A.
1993-01-01
Hairy carbon is a new material developed by growing submicron carbon filaments on conventional carbon substrates. Typical substrate materials include carbon black, graphite powder, carbon fibers, and glassy carbon. A catalyst is used to initiate hair growth with carbonaceous gases serving as the carbon source. To study the electrochemical behavior of hairy carbons, cyclic voltammetry (CV) and discharge testing were conducted. In both cases, hairy carbon results surpassed those of the substrate material alone.
Integrated optics technology study
NASA Technical Reports Server (NTRS)
Chen, B.
1982-01-01
The materials and processes available for the fabrication of single mode integrated electrooptical components are described. Issues included in the study are: (1) host material and orientation, (2) waveguide formation, (3) optical loss mechanisms, (4) wavelength selection, (5) polarization effects and control, (6) laser to integrated optics coupling,(7) fiber optic waveguides to integrated optics coupling, (8) souces, (9) detectors. The best materials, technology and processes for fabrication of integrated optical components for communications and fiber gyro applications are recommended.
Low Dimensional Carbon Materials for Nanooptics and Nanoplasmonics
2015-12-11
structure of the 2D glass supported by a graphene window and identified it as a bi-tetrahedral layer of SiO2 only 3 atoms thick. Our atomic resolution...developed can be directly applied to study other 2D materials such as molybdenum disulfide and 2D glasses . Novel properties in these materials open...up new avenues for studying old and new physics including glass phase transition and valley Hall effect. 15. SUBJECT TERMS graphene, bilayer graphene
NASA Astrophysics Data System (ADS)
Kavner, A.; Armentrout, M. M.; Xie, M.; Weinberger, M.; Kaner, R. B.; Tolbert, S. H.
2010-12-01
A strong synergy ties together the high-pressure subfields of mineral physics, solid-state physics, and materials engineering. The catalog of studies measuring the mechanical properties of materials subjected to large differential stresses in the diamond anvil cell demonstrates a significant pressure-enhancement of strength across many classes of materials, including elemental solids, salts, oxides, silicates, and borides and nitrides. High pressure techniques—both radial diffraction and laser heating in the diamond anvil cell—can be used to characterize the behavior of ultrahard materials under extreme conditions, and help test hypotheses about how composition, structure, and bonding work together to govern the mechanical properties of materials. The principles that are elucidated by these studies can then be used to help design engineering materials to encourage desired properties. Understanding Earth and planetary interiors requires measuring equations of state of relevant materials, including oxides, silicates, and metals under extreme conditions. If these minerals in the diamond anvil cell have any ability to support a differential stress, the assumption of quasi-hydrostaticity no longer applies, with a resulting non-salubrious effect on attempts to measure equation of state. We illustrate these applications with the results of variety of studies from our laboratory and others’ that have used high-pressure radial diffraction techniques and also laser heating in the diamond anvil cell to characterize the mechanical properties of a variety of ultrahard materials, especially osmium metal, osmium diboride, rhenium diboride, and tungsten tetraboride. We compare ambient condition strength studies such as hardness testing with high-pressure studies, especially radial diffraction under differential stress. In addition, we outline criteria for evaluating mechanical properties of materials at combination high pressures and temperatures. Finally, we synthesize our understanding of mechanical properties and composite behavior to suggest new approaches to designing high-pressure experiments to target specific measurements of a wide variety of mechanical properties.
Carbon Nanotube Composites: Strongest Engineering Material Ever?
NASA Technical Reports Server (NTRS)
Mayeaux, Brian; Nikolaev, Pavel; Proft, William; Nicholson, Leonard S. (Technical Monitor)
1999-01-01
The primary goal of the carbon nanotube project at Johnson Space Center (JSC) is to fabricate structural materials with a much higher strength-to-weight ratio than any engineered material today, Single-wall nanotubes present extraordinary mechanical properties along with new challenges for materials processing. Our project includes nanotube production, characterization, purification, and incorporation into applications studies. Now is the time to move from studying individual nanotubes to applications work. Current research at JSC focuses on structural polymeric materials to attempt to lower the weight of spacecraft necessary for interplanetary missions. These nanoscale fibers present unique new challenges to composites engineers. Preliminary studies show good nanotube dispersion and wetting by the epoxy materials. Results of tensile strength tests will also be reported. Other applications of nanotubes are also of interest for energy storage, gas storage, nanoelectronics, field emission, and biomedical uses.
Hatamleh, Muhanad M; Polyzois, Gregory L; Nuseir, Amjad; Hatamleh, Khaldoun; Alnazzawi, Ahmad
2016-07-01
To identify and discuss the findings of publications on mechanical behavior of maxillofacial prosthetic materials published since 1969. Original experimental articles reporting on mechanical properties of maxillofacial prosthetic materials were included. A two-stage search of the literature, electronic and hand search, identified relevant published studies up to May 2015. An extensive electronic search was conducted of databases including PubMed, Embase, Scopus, and Google Scholar. Included primary studies (n = 63) reported on tensile strength, tear strength, and hardness of maxillofacial prosthetic materials at baseline and after aging. The search revealed 63 papers, with more than 28 papers being published in the past 10 years, which shows an increased number of publications when compared to only 6 papers published in the 1970s. The increase is linear with significant correlation (r = 0.85). Such an increase reflects great awareness and continued developments and warrants more research in the field of maxillofacial prosthetic materials properties; however, it is difficult to directly compare results, as studies varied in maxillofacial prosthetic materials tested with various silicone elastomers being heavily investigated, standards followed in preparing test specimens, experimental testing protocols, and parameters used in setting simulated aging conditionings. It is imperative to overcome the existing variability by establishing unified national or international standards/specifications for maxillofacial prosthetic materials. Standardization organizations or bodies, the scientific community, and academia need to be coordinated to achieve this goal. In the meantime and despite all of these theoretically significant alternatives, clinical practice still faces problems with serviceability of maxillofacial prostheses. © 2016 by the American College of Prosthodontists.
Ford, Patrick; Santos, Eduardo; Ferrão, Paulo; Margarido, Fernanda; Van Vliet, Krystyn J; Olivetti, Elsa
2016-05-03
The challenges brought on by the increasing complexity of electronic products, and the criticality of the materials these devices contain, present an opportunity for maximizing the economic and societal benefits derived from recovery and recycling. Small appliances and computer devices (SACD), including mobile phones, contain significant amounts of precious metals including gold and platinum, the present value of which should serve as a key economic driver for many recycling decisions. However, a detailed analysis is required to estimate the economic value that is unrealized by incomplete recovery of these and other materials, and to ascertain how such value could be reinvested to improve recovery processes. We present a dynamic product flow analysis for SACD throughout Portugal, a European Union member, including annual data detailing product sales and industrial-scale preprocessing data for recovery of specific materials from devices. We employ preprocessing facility and metals pricing data to identify losses, and develop an economic framework around the value of recycling including uncertainty. We show that significant economic losses occur during preprocessing (over $70 M USD unrecovered in computers and mobile phones, 2006-2014) due to operations that fail to target high value materials, and characterize preprocessing operations according to material recovery and total costs.
Schoberer, Daniela; Eglseer, Doris; Halfens, Ruud J G; Lohrmann, Christa
2018-06-01
In this study, we describe the development of evidence- and theory-based fall prevention educational material and its evaluation from the users' perspectives. To reduce risk factors for falling in nursing homes, nursing staff must enact multifactorial fall prevention intervention programmes. A core component of these programmes is to educate residents and their family members, both verbally and in a written form. However, users can only benefit from educational material if it is based on current scientific evidence, easy to understand and process and customised. We followed a structured procedure during the development process, while considering various aspect of quality. To assess the understandability and usefulness of the resulting educational materials, we conducted a qualitative content analysis study. The educational materials development process incorporated several iterative steps including a systematic literature search and the application of frameworks for designing and writing the materials. To evaluate the material, we performed six focus group discussions separately with residents, family members and nursing staff from two nursing homes (total of 32 participants). Residents' brochures included clear information on avoiding external risks as well as coping strategies after a fall event. Family members' brochures were more comprehensive, including both concrete tips and outlining the advantages and disadvantages of interventions. Residents and family members had no difficulties understanding the material and tried to apply the content to their individual situations. Nursing staff commented on some ambiguities and incongruities relating to current nursing care practice. By involving users in the development of evidence-based educational materials, nursing staff can achieve a high acceptance rate for the materials and motivate users to address the topic. The involvement of users is essential for developing educational material that meets users' needs. Educational material should be used as part of an overall strategy to educate residents and family members in nursing homes. © 2018 John Wiley & Sons Ltd.
Addressing Machining Issues for the Intermetallic Compound 60-NITINOL
NASA Technical Reports Server (NTRS)
Stanford, Malcolm K.; Wozniak, Walter A.; McCue, Terry R.
2012-01-01
60-NITINOL (60 wt.% Ni - 40 wt.% Ti) is being studied as a material for advanced aerospace components. Frequent wire breakage during electrical-discharge machining of this material was investigated. The studied material was fabricated from hot isostatically pressed 60-NITINOL powder obtained through a commercial source. Bulk chemical analysis of the material showed that the composition was nominal but had relatively high levels of certain impurities, including Al and O. It was later determined that Al2O3 particles had contaminated the material during the hot isostatic pressing procedure and that these particles were the most likely cause of the wire breakage. The results of this investigation highlight the importance of material cleanliness to its further implementation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Toth, James J.; Wall, Donald; Wittman, Richard S.
Target assemblies are provided that can include a uranium-comprising annulus. The assemblies can include target material consisting essentially of non-uranium material within the volume of the annulus. Reactors are disclosed that can include one or more discrete zones configured to receive target material. At least one uranium-comprising annulus can be within one or more of the zones. Methods for producing isotopes within target material are also disclosed, with the methods including providing neutrons to target material within a uranium-comprising annulus. Methods for modifying materials within target material are disclosed as well as are methods for characterizing material within a targetmore » material.« less
In situ vibrational spectroscopy of adsorbed nitrogen in porous carbon materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ray, Paramita; Xu, Enshi; Crespi, Vincent H.
This study uses in situ vibrational spectroscopy to probe nitrogen adsorption to porous carbon materials, including single-wall carbon nanotubes and Maxsorb super-activated carbon, demonstrating how the nitrogen Raman stretch mode is perturbed by adsorption.
AOARD Overview Power and Energy Emphasis
2010-09-01
Evolutionary Research (Incremental Advances) P&E Materials Including Fluids: - Tunable thermal conductivity - Large CTE material matching - Nanofluids ...Charge Rate Objective: • Investigate 10-20x smaller nano-powder particle sizes to shorten charging rate • Study doping transition metals into the
In situ vibrational spectroscopy of adsorbed nitrogen in porous carbon materials
Ray, Paramita; Xu, Enshi; Crespi, Vincent H.; ...
2018-01-01
This study uses in situ vibrational spectroscopy to probe nitrogen adsorption to porous carbon materials, including single-wall carbon nanotubes and Maxsorb super-activated carbon, demonstrating how the nitrogen Raman stretch mode is perturbed by adsorption.
Measurements of dynamic and resilient moduli of roadway test sites.
DOT National Transportation Integrated Search
2013-12-01
This study developed a material input library of dynamic and resilient moduli of local : pavement materials for the Mechanistic Empirical Pavement Design Guide (MEPDG) : implementation in Georgia. A database includes: 1) dynamic moduli of asphalt con...
Studying Popular Culture in the Public Library: Suggestions for Cooperative Programs.
ERIC Educational Resources Information Center
Schroeder, Janet K.
1980-01-01
Offers suggestions for cooperative sharing of resources and expertise between public librarians and their academic colleagues to establish access to popular cultural materials at academic institutions. Listings of materials for popular culture courses are included. (RAA)
Optical Studies and Poling of DNA NLO Waveguides
NASA Astrophysics Data System (ADS)
Heckman, Emily; Grote, James
2005-04-01
Deoxyribonucleic acid (DNA), extracted from salmon sperm through an enzyme isolation process, is precipitated with a surfactant complex, cetyltrimethl-ammonium (CTMA), for application as a nonlinear optical material. Preliminary characterization studies suggest that DNA-CTMA may be suitable for use as the host material in the poled core layer of electro-optically-active waveguide devices. Poling results and techniques for poled chromophore-DNA-CTMA films will be discussed. Optical characterization studies of the DNA-CTMA films, including optical propagation losses and considerations in making DNA-CTMA an optical quality material, will be presented.
A Basic Bibliography on Canada for Social Studies Educators.
ERIC Educational Resources Information Center
Yocum, Michael J.
1988-01-01
Presents a bibliography that provides materials on Canada available to social studies educators. Resources for teachers include teaching strategies, literature guides, and books on acid rain. Student resources include books that provide a perspective on Canadian life. (DB)
Review on electrochromic devices for automotive glazing
NASA Astrophysics Data System (ADS)
Demiryont, Hulya
1991-12-01
Electrochromic materials have been intensively studied for applications of various switchable optical systems. These materials exhibit adjustable optical absorption upon reversible oxidation/reduction processes. Since a reversible oxidation/reduction phenomenon is provided by electrically-driven electrochemical reactions, these materials are known as electrochromics. There are many publications including proceedings, books, and review articles written on electrochromic (EC) materials and their applications. This paper focuses on conventional and some new electrochromic devices (ECD), their specifications, and applications.
Yang, Yun-kuan; Hu, You-ping; Wang, Yan
2006-11-01
Some problems were found for argument in the teaching of The Therapeutics of Acupuncture & Moxibustion, the new centurial national advanced Chinese medical school's planning material, including errors in compiling, some concepts lacking definition, and some acupuncture treatment methods in the material deviating off clinical practice, etc.. Study on these problems so as to make the teaching material more perfect, more scientific, accurate and authoritative.
Preparation of composite materials in space. Volume 2: Technical report
NASA Technical Reports Server (NTRS)
Steurer, W. H.; Kaye, S.
1973-01-01
A study to define promising materials, significant processing criteria, and the related processing techniques and apparatus for the preparation of composite materials in space was conducted. The study also established a program for zero gravity experiments and the required developmental efforts. The following composite types were considered: (1) metal-base fiber and particle composites, including cemented compacts, (2) controlled density metals, comprising plain and reinforced metal foams, and (3) unidirectionally solidified eutectic alloys. A program of suborbital and orbital experiments for the 1972 to 1978 time period was established to identify materials, processes, and required experiment equipment.
Optical contrast for identifying the thickness of two-dimensional materials
NASA Astrophysics Data System (ADS)
Bing, Dan; Wang, Yingying; Bai, Jing; Du, Ruxia; Wu, Guoqing; Liu, Liyan
2018-01-01
One of the most intriguing properties of two-dimensional (2D) materials is their thickness dependent properties. A quick and precise technique to identify the layer number of 2D materials is therefore highly desirable. In this review, we will introduce the basic principle of using optical contrast to determine the thickness of 2D material and also its advantage as compared to other modern techniques. Different 2D materials, including graphene, graphene oxide, transitional metal dichalcogenides, black phosphorus, boron nitride, have been used as examples to demonstrate the capability of optical contrast methods. A simple and more efficient optical contrast image technique is also emphasized, which is suitable for quick and large-scale thickness identification. We have also discussed the factors that could affect the experimental results of optical contrast, including incident light angle, anisotropic nature of materials, and also the twisted angle between 2D layers. Finally, we give perspectives on future development of optical contrast methods for the study and application of 2D materials.
Blade System Design Study. Part II, final project report (GEC).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Griffin, Dayton A.
2009-05-01
As part of the U.S. Department of Energy's Low Wind Speed Turbine program, Global Energy Concepts LLC (GEC)1 has studied alternative composite materials for wind turbine blades in the multi-megawatt size range. This work in one of the Blade System Design Studies (BSDS) funded through Sandia National Laboratories. The BSDS program was conducted in two phases. In the Part I BSDS, GEC assessed candidate innovations in composite materials, manufacturing processes, and structural configurations. GEC also made recommendations for testing composite coupons, details, assemblies, and blade substructures to be carried out in the Part II study (BSDS-II). The BSDS-II contract periodmore » began in May 2003, and testing was initiated in June 2004. The current report summarizes the results from the BSDS-II test program. Composite materials evaluated include carbon fiber in both pre-impregnated and vacuum-assisted resin transfer molding (VARTM) forms. Initial thin-coupon static testing included a wide range of parameters, including variation in manufacturer, fiber tow size, fabric architecture, and resin type. A smaller set of these materials and process types was also evaluated in thin-coupon fatigue testing, and in ply-drop and ply-transition panels. The majority of materials used epoxy resin, with vinyl ester (VE) resin also used for selected cases. Late in the project, testing of unidirectional fiberglass was added to provide an updated baseline against which to evaluate the carbon material performance. Numerous unidirectional carbon fabrics were considered for evaluation with VARTM infusion. All but one fabric style considered suffered either from poor infusibility or waviness of fibers combined with poor compaction. The exception was a triaxial carbon-fiberglass fabric produced by SAERTEX. This fabric became the primary choice for infused articles throughout the test program. The generally positive results obtained in this program for the SAERTEX material have led to its being used in innovative prototype blades of 9-m and 30-m length, as well as other non-wind related structures.« less
Proceedings of the Workshop on an Electromagnetic Positioning System in Space
NASA Technical Reports Server (NTRS)
Oran, W. A. (Editor)
1978-01-01
A workshop was convened to help determine if sufficient justification existed to proceed with the design of an electromagnetic (EM) positioning device for use in space. Those in attendance included experts in crystal growth, nucleation phenomena, containerless processing techniques, properties of materials, metallurgical techniques, and glass technology. Specific areas mentioned included the study of metallic glasses and investigations of the properties of high temperature materials.
Compatibility Studies of Hydrogen Peroxide and a New Hypergolic Fuel Blend
NASA Technical Reports Server (NTRS)
Baldridge, Jennifer; Villegas, Yvonne
2002-01-01
Several preliminary materials compatibility studies have been conducted to determine the practicality of a new hypergolic fuel system. Hypergolic fuel ignites spontaneously as the oxidizer decomposes and releases energy in the presence of the fuel. The bipropellant system tested consists of high-test hydrogen peroxide (HTP) and a liquid fuel blend consisting of a hydrocarbon fuel, an ignition enhancer and a transition metal catalyst. In order for further testing of the new fuel blend to take place, some basic materials compatibility and HTP decomposition studies must be accomplished. The thermal decomposition rate of HTP was tested using gas evolution and isothermal microcalorimetry (IMC). Materials were analyzed for compatibility with hydrogen peroxide including a study of the affect welding has on stainless steel elemental composition and its relation to HTP decomposition. Compatibility studies of valve materials in the fuel blend were performed to determine the corrosion resistance of the materials.
Frictional forces in material removal for glasses and ceramics using magnetorheological finishing
NASA Astrophysics Data System (ADS)
Miao, Chunlin
Magnetorheological finishing (MRF) spotting experiments on stationary parts are conducted in this work to understand the material removal mechanism in MRF. Drag force and normal force are measured in situ, simultaneously for the first time for a variety of optical materials in MRF. We study material removal process in MRF as a function of material mechanical properties. We experimentally demonstrate that material removal in MRF is strongly related to shear stress. Shear stress is predominantly determined by material mechanical properties. A modified Preston's equation is proposed to estimate the material removal in MRF by combining shear stress and material mechanical properties. We investigate extensively the effect of various MRF process parameters, including abrasive concentration, magnetic field strength, penetration depth and wheel speed, on material removal efficiency. Material removal rate model is expanded to include these parameters. We develop a nonaqueous magnetorheological (MR) fluid for examining the mechanical contribution in MRF material removal. This fluid is based on a combination of two CI particles and a combination of two organic liquids. Material removal with this nonaqueous MR fluid is discussed. We formulate a new corrosion resistant MR fluid which is based on metal oxide coated carbonyl iron (CI) particles. The rheological behavior, stability and corrosion resistance are examined.
Micromechanical Characterization and Texture Analysis of Direct Cast Titanium Alloys Strips
NASA Technical Reports Server (NTRS)
2000-01-01
This research was conducted to determine a post-processing technique to optimize mechanical and material properties of a number of Titanium based alloys and aluminides processed via Melt Overflow Solidification Technique (MORST). This technique was developed by NASA for the development of thin sheet titanium and titanium aluminides used in high temperature applications. The materials investigated in this study included conventional titanium alloy strips and foils, Ti-1100, Ti-24Al-11Nb (Alpha-2), and Ti-48Al-2Ta (Gamma). The methodology used included micro-characterization, heat-treatment, mechanical processing and mechanical testing. Characterization techniques included optical, electron microscopy, and x-ray texture analysis. The processing included heat-treatment and mechanical deformation through cold rolling. The initial as-cast materials were evaluated for their microstructure and mechanical properties. Different heat-treatment and rolling steps were chosen to process these materials. The properties were evaluated further and a processing relationship was established in order to obtain an optimum processing condition. The results showed that the as-cast material exhibited a Widmanstatten (fine grain) microstructure that developed into a microstructure with larger grains through processing steps. The texture intensity showed little change for all processing performed in this investigation.
Weightless Environment Training Facility (WETF) Materials Coating Evaluation, Volume 1
NASA Technical Reports Server (NTRS)
1995-01-01
The Weightless Environment Training Facility Material Coating Evaluation project has included preparing, coating, testing, and evaluating 800 test panels of three differing substrates. Ten selected coating systems were evaluated in six separate exposure environments and subject to three tests for physical properties. Substrate materials were identified, the manner of surface preparation described, and exposure environments defined. Exposure environments included immersion exposure, cyclic exposure, and field exposure. Cyclic exposures, specifically QUV-Weatherometer and the KTA Envirotest were found to be the most agressive of the environments included in the study when all three evaluation criteria are considered. This was found to result primarily from chalking of the coatings under ultraviolet (UV) light exposure. Volumes 2 and 3 hold the 5 appendices to this report.
Materials Science Experiments on the International Space Station
NASA Technical Reports Server (NTRS)
Gillies, Donald C.
1999-01-01
The Performance Goal for NASA's Microgravity Materials Science Program reads "Use microgravity to establish and improve quantitative and predictive relationships between the structure, processing and properties of materials." The advent of the International Space Station will open up a new era in Materials Science Research including the ability to perform long term and frequent experiments in microgravity. As indicated the objective is to gain a greater understanding of issues of materials science in an environment in which the force of gravity can be effectively switched off. Thus gravity related issues of convection, buoyancy and hydrostatic forces can be reduced and the science behind the structure/processing/properties relationship can more easily be understood. The specific areas of research covered within the program are (1) the study of Nucleation and Metastable States, (2) Prediction and Control of Microstructure (including pattern formation and morphological stability), (3) Phase Separation and Interfacial Stability, (4) Transport Phenomena (including process modeling and thermophysical properties measurement), and (5) Crystal Growth, and Defect Generation and Control. All classes of materials, including metals and alloys, glasses and ceramics, polymers, electronic materials (including organic and inorganic single crystals), aerogels and nanostructures, are included in these areas. The principal experimental equipment available to the materials scientist on the International Space Station (ISS) will be the Materials Science Research Facility (MSRF). Each of these systems will be accommodated in a single ISS rack, which can operate autonomously, will accommodate telescience operations, and will provide real time data to the ground. Eventual plans call for three MSRF racks, the first of which will be shared with the European Space Agency (ESA). Under international agreements, ESA and other partners will provide some of the equipment, while NASA covers launch and integration costs. The MSRF facilities will include modular components, which can be exchanged to provide inserts specifically matched to the engineering requirements of the particular Principal Investigator. To defray costs and avoid duplication of engineering effort NASA is also pursuing the possibility of using facilities provided by international partners. By this means it is anticipated that all of the types of research outlined in the previous paragraph can be done on the ISS.
Jenkins, Mary M; Reed-Gross, Erika; Barfield, Wanda D; Prue, Christine E; Gallagher, Margaret L; Rasmussen, Sonja A; Honein, Margaret A
2011-11-01
To understand motivations and barriers to participation in studies that include DNA collection, focus group discussions were held with mothers who had participated in a case-control study of birth defects. Recruited mothers had completed an interview and had received a mailed kit containing cytobrushes to collect buccal cells for DNA from herself, her infant, and her infant's father. Six moderator-led focus groups were attended by a total of 38 women residing in Atlanta, Georgia. Focus groups were segmented by DNA collection status (biologics participants or nonparticipants), infant case-control status, infant birthweight, and maternal race and ethnicity. This report assesses maternal attitudes toward study materials and communication strategies. Across groups, respondents expressed concern about how their contact information was obtained. Study materials were described as clear and professional by most women, although some respondents reported confusion about disclosure of individual genetic results. Respondents generally reported that monetary incentives were not a motivation to participate, but increased perceived study legitimacy. Biologics nonparticipants expressed concerns about kit component sterility; government involvement; and DNA sample use, storage, and disposal. Respondents suggested that investigators provide feedback on whether sample collection was performed correctly and provide materials targeted to fathers to help alleviate paternal skepticism. Participation in DNA collection might be improved by strengthening study materials and communication strategies. Published 2011 Wiley Periodicals, Inc. This article is a U.S. Government work and is in the public domain in the USA.
Design, development and applications of novel techniques for studying surface mechanical properties
NASA Technical Reports Server (NTRS)
Miyoshi, Kazuhisa
1989-01-01
Research is reviewed for the adhesion, friction, and micromechanical properties of materials and examples of the results presented. The ceramic and metallic materials studied include silicon carbide, aluminum oxide, and iron-base amorphous alloys. The design and operation of a torsion balance adapted for study of adhesion from the Cavendish balance are discussed first. The pull-off force (adhesion) and shear force (friction) required to break the interfacial junctions between contacting surfaces of the materials were examined at various temperatures in a vacuum. The surface chemistry of the materials was analyzed by X-ray photoelectron spectroscopy. Properties and environmental conditions of the surface regions which affect adhesion and friction-such as surface segregation, composition, crystal structure, surface chemistry, and temperature were also studied.
Barrow, C S; Lucia, H; Stock, M F; Alarie, Y
1979-05-01
The physiological stress imposed upon mice due to the irritating properties of thermal decomposition products of polymeric materials was evaluated. Acute lethality and histopathological evaluation were included in the study. The rankings of the polymeric materials studied from most to least hazardous was concluded to be polytetrafluoroethylene greater than polyvinyl chloride greater than Douglas Fir and flexible polyurethane foam greater than fiber glass reinforced polyester greater than copper coated wire with mineral insulation.
RCRA Sustainable Materials Management Information
This asset includes a broad variety of documents, descriptive data, technical analyses and guidance materials relative to voluntary improvements in resource conservation, the beneficial use of sustainable materials and the management of non-hazardous wastes and materials. Included in this asset are participant information and outreach materials of various voluntary programs relating to better materials and waste management programs. An example is the WasteWise program and Sustainable Materials Management (SMM) Challenges, which help organizations and businesses apply sustainable materials management practices to reduce municipal and select industrial wastes. Also included in this asset are guidance materials to assist municipalities in recycling and reuse of municipal solid waste, including diverting materials to composting, and the use of conversion methods such as anaerobic digestion. Another component are the data necessary to compile reports on the characterization of municipal solid waste (including such waste streams as food waste, yard and wood waste, discarded electronics, and household non-hazardous waste), the recycled content of manufactured goods, and other analyses performed using such tools as the Waste Assessment Reduction Model (WARM).For industrial non-hazardous waste, this asset includes guidance and outreach materials on industrial materials recycling and waste minimization. Finally, this asset includes research analyses on sustainable materia
BUILDING MATERIALS RECLAMATION PROGRAM
DOE Office of Scientific and Technical Information (OSTI.GOV)
David C. Weggel; Shen-En Chen; Helene Hilger
2010-08-31
This report describes work conducted on the Building Materials Reclamation Program for the period of September 2008 to August 2010. The goals of the project included selecting materials from the local construction and demolition (C&D) waste stream and developing economically viable reprocessing, reuse or recycling schemes to divert them from landfill storage. Educational resources as well as conceptual designs and engineering feasibility demonstrations were provided for various aspects of the work. The project was divided into two distinct phases: Research and Engineering Feasibility and Dissemination. In the Research Phase, a literature review was initiated and data collection commenced, an advisorymore » panel was organized, and research was conducted to evaluate high volume C&D materials for nontraditional use; five materials were selected for more detailed investigations. In the Engineering Feasibility and Dissemination Phase, a conceptual study for a regional (Mecklenburg and surrounding counties) collection and sorting facility was performed, an engineering feasibility project to demonstrate the viability of recycling or reuse schemes was created, the literature review was extended and completed, and pedagogical materials were developed. Over the two-year duration of the project, all of the tasks and subtasks outlined in the original project proposal have been completed. The Final Progress Report, which briefly describes actual project accomplishments versus the tasks/subtasks of the original project proposal, is included in Appendix A of this report. This report describes the scientific/technical aspects (hypotheses, research/testing, and findings) of six subprojects that investigated five common C&D materials. Table 1 summarizes the six subprojects, including the C&D material studied and the graduate student and the faculty advisor on each subproject.« less
ERIC Educational Resources Information Center
Delaware Univ., Newark. Coll. of Education.
This unit on fossils is designed for junior high school students. Students collect a sediment sample, process the sample, and examine it for microfossils. The scientific classification and naming of microfossils is not stressed. Included in the materials are evaluation items, background materials for teachers, lists of needed materials, vocabulary…
NASA Technical Reports Server (NTRS)
1975-01-01
Development and understanding of materials most suitable for use in compact magnetic and optical memory systems are discussed. Suppression of metal deterioration by hydrogen is studied. Improvement of mechanical properties of polymers is considered, emphasizing low temperature ductility and compatibility with high modulus fiber materials.
Chicanos: A Checklist of Current Materials, No. 1, January-June 1985.
ERIC Educational Resources Information Center
Guerena, Salvador, Comp.; Gonzalez, Raquel Quiroz, Comp.
This bibliography contains entries for 230 items in the field of Chicano Area Studies by the Coleccion Tloque Nahuaque, within the Library of the University of California at Santa Barbara. Books and booklets are listed which contain materials on a number of areas including art, arts and crafts, bibliographies, bilingual education, border studies,…
Applying Augmented Reality to Enhance Learning: A Study of Different Teaching Materials
ERIC Educational Resources Information Center
Hung, Y.-H.; Chen, C.-H.; Huang, S.-W.
2017-01-01
The objective of this study was to determine the usefulness of augmented reality (AR) in teaching. An experiment was conducted to examine children's learning performances, which included the number of errors they made, their ability to remember the content of what they had read and their satisfaction with the three types of teaching materials,…
Russian Language Analysis Project
ERIC Educational Resources Information Center
Serianni, Barbara; Rethwisch, Carolyn
2011-01-01
This paper is the result of a language analysis research project focused on the Russian Language. The study included a diverse literature review that included published materials as well as online sources in addition to an interview with a native Russian speaker residing in the United States. Areas of study include the origin and history of the…
Materials Science Research Rack Onboard the International Space Station
NASA Technical Reports Server (NTRS)
Reagan, Shawn E.; Lehman, John R.; Frazier, Natalie C.
2014-01-01
The Materials Science Research Rack (MSRR) is a highly automated facility developed in a joint venture/partnership between NASA and ESA center dot Allows for the study of a variety of materials including metals, ceramics, semiconductor crystals, and glasses onboard the International Space Station (ISS) center dot Multi-user facility for high temperature materials science research center dot Launched on STS-128 in August 2009, and is currently installed in the U.S. Destiny Laboratory Module ?Research goals center dot Provide means of studying materials processing in space to develop a better understanding of the chemical and physical mechanisms involved center dot Benefit materials science research via the microgravity environment of space where the researcher can better isolate the effects of gravity during solidification on the properties of materials center dot Use the knowledge gained from experiments to make reliable predictions about conditions required on Earth to achieve improved materials
Porous graphene nanocages for battery applications
Amine, Khalil; Lu, Jun; Du, Peng; Wen, Jianguo; Curtiss, Larry A.
2017-03-07
An active material composition includes a porous graphene nanocage and a source material. The source material may be a sulfur material. The source material may be an anodic material. A lithium-sulfur battery is provided that includes a cathode, an anode, a lithium salt, and an electrolyte, where the cathode of the lithium-sulfur battery includes a porous graphene nanocage and a sulfur material and at least a portion of the sulfur material is entrapped within the porous graphene nanocage. Also provided is a lithium-air battery that includes a cathode, an anode, a lithium salt, and an electrolyte, where the cathode includes a porous graphene nanocage and where the cathode may be free of a cathodic metal catalyst.
Schneider, T; Arumi, D; Crook, T J; Sun, F; Michel, M C
2014-09-01
To compare the effects of additional educational material on treatment satisfaction of overactive bladder (OAB) patients treated with a muscarinic receptor antagonist. In an observational study of OAB patients being treated by their physician with fesoterodine for 4 months (FAKTEN study), sites were randomised to providing standard treatment or additional educational material including the SAGA tool. Patient satisfaction was assessed by three validated patient-reported outcomes including the Treatment Satisfaction Question. Because of premature discontinuation of the study, descriptive statistical analysis was performed. A total of 431 and 342 patients received standard treatment or additional educational material, respectively. At study end, 76.1% [95% CI = 71.3, 80.4] of patients with standard care and 79.6% [95% CI = 74.4, 84.1] with additional SAGA tool were satisfied with treatment (primary end-point). Comparable outcomes with and without the additional educational material were also found in various patient subgroups, at the 1-month time point, and for the other patient-reported outcomes. A notable exception was the subgroup of treatment-naïve patients in which the percentage of satisfied patients was 77.2% vs. 89.5% with standard treatment and additional SAGA tool, respectively (post hoc analysis). In an observational study, most overactive bladder patients were satisfied with fesoterodine treatment. Because of the small sample size, the study does not support or refute the hypothesis that adding the SAGA tool will improve patient satisfaction with treatment. The potential effect of additional educational material in treatment-naïve patients warrants further dedicated studies. © 2014 John Wiley & Sons Ltd.
Comparative study of the physical properties of core materials.
Saygili, Gülbin; Mahmali, Sevil M
2002-08-01
This study was undertaken to measure physical properties of materials used for direct core buildups, including high-copper amalgam, visible light-cured resin composite, autocured titanium-containing composite, polyacid-modified composite, resin-modified glass-ionomer, and silver cermet cement. Compressive strength, diametral tensile strength, and flexural strength of six core materials of various material classes were measured for each material as a function of time up to 3 months at different storage conditions, using a standard specification test designed for the materials. Three different storage conditions (dry, humid, wet) at 37 degrees C were chosen. Materials were manipulated according to manufacturers' instructions for use as cores. Mean compressive, diametral tensile, and flexural strengths with associated standard deviations were calculated for each material. Multiple comparison and Newman-Keuls tests discerned many differences among materials. All materials were found to meet the minimum specification requirements, except in terms of flexural strength for amalgam after 1 hour and the silver cermet at all time intervals.
NASA Astrophysics Data System (ADS)
Zielinski, Jonas; Mindt, Hans-Wilfried; Düchting, Jan; Schleifenbaum, Johannes Henrich; Megahed, Mustafa
2017-12-01
Powder bed fusion additive manufacturing of titanium alloys is an interesting manufacturing route for many applications requiring high material strength combined with geometric complexity. Managing powder bed fusion challenges, including porosity, surface finish, distortions and residual stresses of as-built material, is the key to bringing the advantages of this process to production main stream. This paper discusses the application of experimental and numerical analysis towards optimizing the manufacturing process of a demonstration component. Powder characterization including assessment of the reusability, assessment of material consolidation and process window optimization is pursued prior to applying the identified optima to study the distortion and residual stresses of the demonstrator. Comparisons of numerical predictions with measurements show good correlations along the complete numerical chain.
Leng, Chuan; Sun, Shuwen; Zhang, Kexin; Jiang, Shaoyi; Chen, Zhan
2016-08-01
Antifouling polymers have wide applications in biomedical engineering and marine industry. Recently, zwitterionic materials have been reported as promising candidates for antifouling applications, while strong hydration is believed to be the key antifouling mechanism. Zwitterionic materials can be designed with various molecular structures, which affect their hydration and antifouling performance. Although strong hydration has been proposed to occur at the material surfaces, probing the solid material/water interfaces is challenging with traditional analytical techniques. Here in this review, we will review our studies on surface hydration of zwitterionic materials and other antifouling materials by using sum frequency generation (SFG) vibrational spectroscopy, which provides molecular understanding of the water structures at various material surfaces. The materials studied include zwitterionic polymer brushes with different molecular structures, amphiphilic polymers with zwitterionic groups, uncharged hydrophilic polymer brushes, amphiphilic polypeptoids, and widely used antifouling material poly(ethylene glycol). We will compare the differences among zwitterionic materials with various molecular structures as well as the differences between antifouling materials and fouling surfaces of control samples. We will also discuss the effects of pH and biological molecules like proteins on the surface hydration of the zwitterionic materials. Using SFG spectroscopy, we have measured the hydration layers of antifouling materials and found that strong hydrogen bonds are key to the formation of strong hydration layers preventing protein fouling at the polymer interfaces. Antifouling polymers have wide applications in biomedical engineering and marine industry. Recently, zwitterionic materials have been reported as promising candidates for antifouling applications, while strong hydration is believed to be the key antifouling mechanism. However, zwitterionic materials can be designed with various molecular structures, which affect their hydration and antifouling performance. Moreover, although strong hydration has been proposed to occur at the material surfaces, probing the solid material/water interfaces is challenging with traditional analytical techniques. Here in this manuscript, we will review our studies on surface hydration of zwitterionic materials and other antifouling materials by using sum frequency generation (SFG) vibrational spectroscopy, which provides molecular understanding of the water structures at various material surfaces. The materials studied include zwitterionic polymer brushes with different molecular structures, amphiphilic polymers with zwitterionic groups, uncharged hydrophilic polymer brushes, amphiphilic polypeptoids, and widely used antifouling material poly(ethylene glycol). We will compare the differences among zwitterionic materials with various molecular structures as well as the differences between antifouling materials and fouling surfaces of control samples. We will also discuss the effects of pH and biological molecules like proteins on the surface hydration of the zwitterionic materials. All the SFG results indicate that strongly hydrogen-bonded water at the materials' surfaces (strong surface hydration) is closely correlated to the good antifouling properties of the materials. This review will be widely interested by readers of Acta Biomaterialia and will impact many different research fields in chemistry, materials, engineering, and beyond. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Ultrahigh-Temperature Ceramics
NASA Technical Reports Server (NTRS)
Johnson, Sylvia M.; Ellerby, Donald T.; Beckman, Sarah E.; Irby, Edward; Gasch, Matthew J.; Gusman, Michael I.
2007-01-01
Ultrahigh temperature ceramics (UHTCs) are a class of materials that include the diborides of metals such as hafnium and zirconium. The materials are of interest to NASA for their potential utility as sharp leading edges for hypersonic vehicles. Such an application requires that the materials be capable of operating at temperatures, often in excess of 2,000 C. UHTCs are highly refractory and have high thermal conductivity, an advantage for this application. UHTCs are potentially applicable for other high-temperature processing applications, such as crucibles for molten-metal processing and high-temperature electrodes. UHTCs were first studied in the 1960 s by the U.S. Air Force. NASA s Ames Research Center concentrated on developing materials in the HfB2/SiC family for a leading-edge application. The work focused on developing a process to make uniform monolithic (2-phase) materials, and on the testing and design of these materials. Figure 1 shows arc-jet models made from UHTC materials fabricated at Ames. Figure 2 shows a cone being tested in the arc-jet. Other variations of these materials being investigated elsewhere include zirconium based materials and fiber-reinforced composites. Current UHTC work at Ames covers four broad topics: monoliths, coatings, composites, and processing. The goals include improving the fracture toughness, thermal conductivity and oxidation resistance of monolithic UHTCs and developing oxidation-resistant UHTC coatings for thermal-protection-system substrates through novel coating methods. As part of this effort, researchers are exploring compositions and processing changes that have yielded improvements in properties. Computational materials science and nanotechnology are being explored as approaches to reduce materials development time and improve and tailor properties.
NASA Technical Reports Server (NTRS)
Misra, Ajay K.
1989-01-01
Chemical compatibility of several reinforcement materials with three niobium aluminides, Nb3Al, Nb2Al, and NbAl3, were examined from thermodynamic considerations. The reinforcement materials considered in this study include carbides, borides, nitrides, oxides, silicides, and Engel-Brewer compounds. Thermodynamics of the Nb-Al system were reviewed and activities of Nb and Al were derived at desired calculation temperatures. Criteria for chemical compatibility between the reinforcement material and Nb-Al compounds have been defined and several chemically compatible reinforcement materials have been identified.
A study of the stress wave factor technique for evaluation of composite materials
NASA Technical Reports Server (NTRS)
Duke, J. C., Jr.; Henneke, E. G., II; Kiernan, M. T.; Grosskopf, P. P.
1989-01-01
The acousto-ultrasonic approach for nondestructive evaluation provides a measurement procedure for quantifying the integrated effect of globally distributed damage characteristic of fiber reinforced composite materials. The evaluation procedure provides a stress wave factor that correlates closely with several material performance parameters. The procedure was investigated for a variety of materials including advanced composites, hybrid structure bonds, adhesive bonds, wood products, and wire rope. The research program focused primarily on development of fundamental understanding and applications advancements of acousto-ultrasonics for materials characterization. This involves characterization of materials for which detection, location, and identification of imperfections cannot at present be analyzed satisfactorily with mechanical performance prediction models. In addition to presenting definitive studies on application potentials, the understanding of the acousto-ultrasonic method as applied to advanced composites is reviewed.
Anthropology. Teacher's Resource Packet.
ERIC Educational Resources Information Center
Smithsonian Institution, Washington, DC. Museum of Natural History.
This document is a collection of materials developed for the Smithsonian Institution/George Washington University Anthropology for Teachers Program. The program was established to encourage junior and senior high school teachers to integrate anthropology into their social studies and science classes. The materials include several bibliographies:…
CHILD DEVELOPMENT BIBLIOGRAPHY. SUPPLEMENT I.
ERIC Educational Resources Information Center
Harvard Univ., Cambridge, MA. Graduate School of Education.
THIS BIBLIOGRAPHY SUPPLEMENT LISTS MATERIAL ON VARIOUS ASPECTS OF CHILD DEVELOPMENT. APPROXIMATELY 90 UNANNOTATED REFERENCES ARE PROVIDED TO DOCUMENTS DATING FROM 1956 TO 1966. JOURNALS, BOOKS, AND REPORT MATERIALS ARE LISTED. SUBJECT AREAS INCLUDED ARE BEHAVIOR TESTS, CONDITIONING, MATERNAL REACTIONS, GRADE PREDICTABILITY, EXPERIMENTAL STUDIES,…
ERIC Educational Resources Information Center
Harvard Univ., Cambridge, MA. Graduate School of Education.
THIS BIBLIOGRAPHY LISTS MATERIAL ON VARIOUS ASPECTS OF CREATIVITY. APPROXIMATELY 50 UNANNOTATED REFERENCES ARE PROVIDED TO DOCUMENTS DATING FROM 1961 TO 1966. JOURNALS, BOOKS, AND REPORT MATERIALS ARE LISTED. SUBJECT AREAS INCLUDED ARE (1) IDENTIFICATION, DEVELOPMENT, AND MEASUREMENT OF CREATIVITY, (2) PSYCHOLOGICAL STUDIES OF CREATIVITY, (3)…
ERIC Educational Resources Information Center
Blaga, Jeff; And Others
Designed primarily for teachers of students in grades 7-12, the document presents over 60 social studies teaching strategies and lesson plans. Each lesson includes an overview, grade level information, suggested course/subject matter uses, objectives, suggested materials, student materials, and an instructional plan. Lesson topics fall into the…
ERIC Educational Resources Information Center
Miller, J. Dale
Supplementary teaching materials for French language programs are presented in this text. Primarily intended for secondary school students, the study contains seven units of material. They include: (1) French gestures, (2) teaching the interrogative pronouns, (3) French cuisine, (4) recreational learning games, (5) French-English cognates, (6)…
Floating the Ball: Advances in the Technology of Electrostatic Levitation
NASA Technical Reports Server (NTRS)
Rogers, Jan R.
2006-01-01
Electrostatic Levitation (ESL) is an emerging technology. The MSFC ESL is a NASA facility that supports investigations of refractory solids and melts. The facility can be used to process a wide variety of materials including metals, alloys, ceramics, glasses and semiconductors. Containerless processing via ESL provides a high-purity environment for the study of high temperature materials and access to metastable states. Scientific topics investigated in the facility include nucleation, undercooling, metastable state formation and metallic glass formation. Additionally, the MSFC ESL provides data for the determination of phase diagrams, time-temperature-transition diagrams, viscosity, surface tension, density, heat capacity and creep resistance. In order to support a diverse research community, the MSFC ESL facility has developed a number of technical capabilities, including a portable system for in situ studies of structural tran$hrmations during processing at the high-energy X-ray beamline at the Advanced Photon Source of Argonne National Laboratory. The capabilities of the MSFC ESL facilities will be discussed and selected results of materials processing and characterization studies will be presented.
Technical accomplishments of the NASA Lewis Research Center, 1989
NASA Technical Reports Server (NTRS)
1990-01-01
Topics addressed include: high-temperature composite materials; structural mechanics; fatigue life prediction for composite materials; internal computational fluid mechanics; instrumentation and controls; electronics; stirling engines; aeropropulsion and space propulsion programs, including a study of slush hydrogen; space power for use in the space station, in the Mars rover, and other applications; thermal management; plasma and radiation; cryogenic fluid management in space; microgravity physics; combustion in reduced gravity; test facilities and resources.
NASA Technical Reports Server (NTRS)
Strickland, Edwin L., III
1992-01-01
Classification and mapping of surficial units in the central equatorial region of Mars Consortium data identified the relatively dark but 'red' materials that cover Lunae Planum and surround the Meridiani materials of Oxia Palus inertia region of Arabia. Oxia Province consists of the regions dominated by the characteristically dark 'red' Oxia materials, but it includes darker streaks and splotches of relatively 'blue' Meridiani materials and brighter 'red' deposits of dust belonging to Eos Province (the bright 'red' border between Oxia and regional Meridiani deposits to the south) and Xanthe Province (the moderately bright 'red' dust deposits in western Chryse Planitia and its vicinity, including the VL-1 landing site). Two Oxia units were recognized: a darker unit present on Lunae Planum and east of Oxia Palus that have intermediate to high inertias. Oxia Province surrounds the extremely low thermal inertia Arabia Province in the east part of the study area, and occurs as isolated patches within Arabia (often including splotches of Meridiani materials within the Oxia patches). Arabia Province's materials have been widely interpreted as unconsolidated dust deposits which are currently forming at this stage of Mars' precessional climate cycle, although the persistence of stable, moderately strong albedo contracts among Arabia materials has not been addressed in those models. A systematic interpretation of Oxia and Arabia Province materials based on currently available remote sensing data is given.
The quality and suitability of written educational materials for patients*.
Demir, Fatma; Ozsaker, Esma; Ilce, Arzu Ozcan
2008-01-01
In this study, the quality and suitability of written educational materials being used for the education of patients in surgical departments of hospitals were studied. In the literature, it is stated that most of the educational materials for patients are not suitable from the aspects of contents, structure, design, composition and language. In this descriptive type study, which was carried out between March and May 2006, 59 examples of written educational material used for patient education at 138 surgical clinics were evaluated for quality and suitability. The written educational materials obtained were evaluated independently by researchers from the aspect of quality and suitability. The DISCERN measuring instrument was used in the evaluation of the reliability of the written educational materials and the Evaluation of the Suitability of Written Materials form was used in the evaluation of suitability. It was determined that the educational materials received low scores for reliability and information quality. It was determined that the total scores for the written educational materials were average for suitability. It was determined that there were no written educational materials in more than half of the surgical units included in the study. It was also found that the educational materials had serious deficiencies. This study showed that there was no adequate written patient educational material at the clinics. This deficiency in written educational materials could be eliminated by having them prepared by health professionals in accordance with guidebooks and taking the target group into account.
Systems and strippable coatings for decontaminating structures that include porous material
Fox, Robert V [Idaho Falls, ID; Avci, Recep [Bozeman, MT; Groenewold, Gary S [Idaho Falls, ID
2011-12-06
Methods of removing contaminant matter from porous materials include applying a polymer material to a contaminated surface, irradiating the contaminated surface to cause redistribution of contaminant matter, and removing at least a portion of the polymer material from the surface. Systems for decontaminating a contaminated structure comprising porous material include a radiation device configured to emit electromagnetic radiation toward a surface of a structure, and at least one spray device configured to apply a capture material onto the surface of the structure. Polymer materials that can be used in such methods and systems include polyphosphazine-based polymer materials having polyphosphazine backbone segments and side chain groups that include selected functional groups. The selected functional groups may include iminos, oximes, carboxylates, sulfonates, .beta.-diketones, phosphine sulfides, phosphates, phosphites, phosphonates, phosphinates, phosphine oxides, monothio phosphinic acids, and dithio phosphinic acids.
Metal-organic framework materials with ultrahigh surface areas
Farha, Omar K.; Hupp, Joseph T.; Wilmer, Christopher E.; Eryazici, Ibrahim; Snurr, Randall Q.; Gomez-Gualdron, Diego A.; Borah, Bhaskarjyoti
2015-12-22
A metal organic framework (MOF) material including a Brunauer-Emmett-Teller (BET) surface area greater than 7,010 m.sup.2/g. Also a metal organic framework (MOF) material including hexa-carboxylated linkers including alkyne bond. Also a metal organic framework (MOF) material including three types of cuboctahedron cages fused to provide continuous channels. Also a method of making a metal organic framework (MOF) material including saponifying hexaester precursors having alkyne bonds to form a plurality of hexa-carboxylated linkers including alkyne bonds and performing a solvothermal reaction with the plurality of hexa-carboxylated linkers and one or more metal containing compounds to form the MOF material.
Lillo, Thomas M.; Chu, Henry S.; Harrison, William M.; Bailey, Derek
2013-01-22
Methods of forming composite materials include coating particles of titanium dioxide with a substance including boron (e.g., boron carbide) and a substance including carbon, and reacting the titanium dioxide with the substance including boron and the substance including carbon to form titanium diboride. The methods may be used to form ceramic composite bodies and materials, such as, for example, a ceramic composite body or material including silicon carbide and titanium diboride. Such bodies and materials may be used as armor bodies and armor materials. Such methods may include forming a green body and sintering the green body to a desirable final density. Green bodies formed in accordance with such methods may include particles comprising titanium dioxide and a coating at least partially covering exterior surfaces thereof, the coating comprising a substance including boron (e.g., boron carbide) and a substance including carbon.
Visible scintillation photodetector device incorporating chalcopyrite semiconductor crystals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stowe, Ashley C.; Burger, Arnold
2017-04-04
A photodetector device, including: a scintillator material operable for receiving incident radiation and emitting photons in response; a photodetector material coupled to the scintillator material operable for receiving the photons emitted by the scintillator material and generating a current in response, wherein the photodetector material includes a chalcopyrite semiconductor crystal; and a circuit coupled to the photodetector material operable for characterizing the incident radiation based on the current generated by the photodetector material. Optionally, the scintillator material includes a gamma scintillator material and the incident radiation received includes gamma rays. Optionally, the photodetector material is further operable for receiving thermalmore » neutrons and generating a current in response. The circuit is further operable for characterizing the thermal neutrons based on the current generated by the photodetector material.« less
Nanostructured Thermal Protection Systems for Space Exploration Missions
NASA Technical Reports Server (NTRS)
Arnold, J. O.; Chen, Y. K.; Squire, T.; Srivastava, D.; Allen, G., Jr.; Stackpoole, M.; Goldstein, H. E.; Venkatapathy, E.; Loomis, M. P.
2005-01-01
Strong research and development programs in nanotechnology and Thermal Protection Systems (TPS) exist at NASA Ames. Conceptual studies have been undertaken to determine if new, nanostructured materials (composites of existing TPS materials and nanostructured composite fibers) could improve the performance of TPS. To this end, we have studied various candidate heatshields, some composed of existing TPS materials (with known material properties), to provide a baseline for comparison with others that are admixtures of such materials and a nanostructured material. In the latter case, some assumptions were made about the thermal conductivity and strength of the admixture, relative to the baseline TPS material. For the purposes of this study, we have made the conservative assumption that only a small fraction of the remarkable properties of carbon nanotubes (for example) will be realized in the material properties of the admixtures employing them. The heatshields studied included those for Sharp leading edges (appropriate to out-of-orbit entry and aero-maneuvering), probes, an out-of-orbit Apollo Command Module (as a surrogate for NASA's new Crew Exploration Vehicle [CEV]), a Mars Sample Return Vehicle and a large heat shield for Mars aerocapture missions. We report on these conceptual studies, which show that in some cases (not all), significant improvements in the TPS can be achieved through the use of nanostructured materials.
Fatigue and fracture mechanical behavior for Chinese A508-3 steel at room temperature
NASA Astrophysics Data System (ADS)
Shi, K. K.; Xie, H.; Zheng, B.; Fu, X. L.
2018-06-01
Material, A508-3 steel, has been used in nuclear reactor vessels. In the present study, fatigue and fracture mechanical behavior of Chinese A5083 steel at room temperature are studied by mechanical material testing machine (MTS). Test data of material’s mechanical behavior including uniaxial tension, low cycle fatigue (LCF), threshold value of stress intensity factor (SIF) range, fatigue crack growth (FCG), and fracture toughness is generated and given for further study. It is worth noting that the model in predicting FCG of material from LCF parameters is verified and discussed.
A Review of Microwave Thermography Nondestructive Testing and Evaluation
Zhang, Hong; Yang, Ruizhen; He, Yunze; Foudazi, Ali; Cheng, Liang; Tian, Guiyun
2017-01-01
Microwave thermography (MWT) has many advantages including strong penetrability, selective heating, volumetric heating, significant energy savings, uniform heating, and good thermal efficiency. MWT has received growing interest due to its potential to overcome some of the limitations of microwave nondestructive testing (NDT) and thermal NDT. Moreover, during the last few decades MWT has attracted growing interest in materials assessment. In this paper, a comprehensive review of MWT techniques for materials evaluation is conducted based on a detailed literature survey. First, the basic principles of MWT are described. Different types of MWT, including microwave pulsed thermography, microwave step thermography, microwave pulsed phase thermography, and microwave lock-in thermography are defined and introduced. Then, MWT case studies are discussed. Next, comparisons with other thermography and NDT methods are conducted. Finally, the trends in MWT research are outlined, including new theoretical studies, simulations and modelling, signal processing algorithms, internal properties characterization, automatic separation and inspection systems. This work provides a summary of MWT, which can be utilized for material failures prevention and quality control. PMID:28505130
Systems and methods for treating material
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scheele, Randall D; McNamara, Bruce K
Systems for treating material are provided that can include a vessel defining a volume, at least one conduit coupled to the vessel and in fluid communication with the vessel, material within the vessel, and NF.sub.3 material within the conduit. Methods for fluorinating material are provided that can include exposing the material to NF.sub.3 to fluorinate at least a portion of the material. Methods for separating components of material are also provided that can include exposing the material to NF.sub.3 to at least partially fluorinate a portion of the material, and separating at least one fluorinated component of the fluorinated portionmore » from the material. The materials exposed to the NF.sub.3 material can include but are not limited to one or more of U, Ru, Rh, Mo, Tc, Np, Pu, Sb, Ag, Am, Sn, Zr, Cs, Th, and/or Rb.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
This Feasibility Analysis covers a wide range of studies and evaluations. The Report is divided into five parts. Section 1 contains all material relating to the Institutional Assessment including consideration of the requirements and position of the Potomac Electric Co. as they relate to cogeneration at Georgetown in parallel with the utility (Task 1). Sections 2 through 7 contain all technical information relating to the Alternative Subsystems Analysis (Task 4). This includes the energy demand profiles upon which the evaluations were based (Task 3). It further includes the results of the Life-Cycle-Cost Analyses (Task 5) which are developed in detailmore » in the Appendix for evaluation in the Technical Report. Also included is the material relating to Incremental Savings and Optimization (Task 6) and the Conceptual Design for candidate alternate subsystems (Task 7). Section 8 contains all material relating to the Environmental Impact Assessment (Task 2). The Appendix contains supplementary material including the budget cost estimates used in the life-cycle-cost analyses, the basic assumptions upon which the life-cycle analyses were developed, and the detailed life-cycle-cost anlysis for each subsystem considered in detail.« less
New imaging systems in nuclear medicine. Final report, January 1, 1993--December 31, 1995
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1995-12-31
The aim of this program has been to improve the performance of positron emission tomography (PET) to achieve high resolution with high sensitivity. Towards this aim, the authors have carried out the following studies: (1) explored new techniques for detection of annihilation radiation including new detector materials and system geometries, specific areas that they have studied include--exploration of factors related to resolution and sensitivity of PET instrumentation including geometry, detection materials and coding, and the exploration of technique to improve the image quality by use of depth of interaction and increased sampling; (2) complete much of the final testing ofmore » PCR-II, an analog-coded cylindrical positron tomograph, developed and constructed during the current funding period; (3) developed the design of a positron microtomograph with mm resolution for quantitative studies in small animals, a single slice version of this device has been designed and studied by use of computer simulation; (4) continued and expanded the program of biological studies in animal models. Current studies have included imaging of animal models of Parkinson`s and Huntington`s disease and cancer. These studies have included new radiopharmaceuticals and techniques involving molecular biology.« less
Thermophysical Property Testing Using Transient Techniques.
1984-06-29
WORDS (Continue on reverse side if necessary and identify by block number) Specific heat HMX carbon/carbon Diffusivity RDX solid propellants Conductivity...energetic materials (AP, " HMX , RDX and HTPB) used in solid rocket fuel to carbon/carbon materials used as rocket nozzles. Studies on AP included single...32 4.1b HMX and RDX ............................35 a 4.2 Carbon/Carbon Materials ...................... 36 5.0 SUMMARY
Real-time and accelerated outdoor endurance testing of solar cells
NASA Technical Reports Server (NTRS)
Forestieri, A. F.; Anagnostou, E.
1978-01-01
Materials for solar-cell module construction have been studied on the basis of limited real-time outdoor exposure evaluations. The materials tested included transmission samples, sub-modules, and actual solar cells. The results suggest that glass, fluorinated ethylene propylene, and perfluoroalkoxy are good materials for the covering or encapsulation of solar-cell modules. In all cases, dirt accumulation and cleanability are important factors.
ERIC Educational Resources Information Center
Lenski, Susan; Larson, Mindy; McElhone, Dot; Davis, Dennis S.; Lauritzen, Carol; Villagómez, Amanda; Yeigh, Maika; Landon-Hays, Melanie; LeJeune, Marie; Scales, W. David
2016-01-01
This study reports the results of a survey of a representative sample of 1,206 elementary reading and English Language Arts teachers in Oregon to learn (1) what materials are currently being used, (2) what materials teachers would prefer, and (3) what instructional practices teachers use. Qualitative data included 365 comments and 34 interviews…
Comparative study of hydrogen storage on metal doped mesoporous materials
NASA Astrophysics Data System (ADS)
Carraro, P. M.; Sapag, K.; Oliva, M. I.; Eimer, G. A.
2018-06-01
The hydrogen adsorption capacity of mesoporous materials MCM-41 modified with Co, Fe, Ti, Mg and Ni at 77 K and 10 bar was investigated. Various techniques including XRD, N2 adsorption and DRUV-vis were employed for the materials characterization. The results showed that a low nickel loading on MCM-41 support promoted the presence of hydrogen-favorable sites, increasing the hydrogen storage capacity.
Nanostructure studies of strongly correlated materials.
Wei, Jiang; Natelson, Douglas
2011-09-01
Strongly correlated materials exhibit an amazing variety of phenomena, including metal-insulator transitions, colossal magnetoresistance, and high temperature superconductivity, as strong electron-electron and electron-phonon couplings lead to competing correlated ground states. Recently, researchers have begun to apply nanostructure-based techniques to this class of materials, examining electronic transport properties on previously inaccessible length scales, and applying perturbations to drive systems out of equilibrium. We review progress in this area, particularly emphasizing work in transition metal oxides (Fe(3)O(4), VO(2)), manganites, and high temperature cuprate superconductors. We conclude that such nanostructure-based studies have strong potential to reveal new information about the rich physics at work in these materials.
NASA Technical Reports Server (NTRS)
Wright, Geoff
1994-01-01
This report will discuss the design of a liquid hydrogen fuel tank constructed from composite materials. The focus of this report is to recommend a design for a fuel tank which will be able to withstand all static and dynamic forces during manned flight. Areas of study for the design include material selection, material structural analysis, heat transfer, thermal expansion, and liquid hydrogen diffusion. A structural analysis FORTRAN program was developed for analyzing the buckling and yield characteristics of the tank. A thermal analysis Excel spreadsheet was created to determine a specific material thickness which will minimize heat transfer through the wall of the tank. The total mass of the tank was determined by the combination of both structural and thermal analyses. The report concludes with the recommendation of a layered material tank construction. The designed system will include exterior insulation, combination of metal and organize composite matrices and honeycomb.
Peng, Qing; Dearden, Albert K; Crean, Jared; Han, Liang; Liu, Sheng; Wen, Xiaodong; De, Suvranu
2014-01-01
Plenty of new two-dimensional materials including graphyne, graphdiyne, graphone, and graphane have been proposed and unveiled after the discovery of the "wonder material" graphene. Graphyne and graphdiyne are two-dimensional carbon allotropes of graphene with honeycomb structures. Graphone and graphane are hydrogenated derivatives of graphene. The advanced and unique properties of these new materials make them highly promising for applications in next generation nanoelectronics. Here, we briefly review their properties, including structural, mechanical, physical, and chemical properties, as well as their synthesis and applications in nanotechnology. Graphyne is better than graphene in directional electronic properties and charge carriers. With a band gap and magnetism, graphone and graphane show important applications in nanoelectronics and spintronics. Because these materials are close to graphene and will play important roles in carbon-based electronic devices, they deserve further, careful, and thorough studies for nanotechnology applications.
ERIC Educational Resources Information Center
Chandler-Olcott, Kelly; Doerr, Helen M.; Hinchman, Kathleen A.; Masingila, Joanna O.
2015-01-01
This 3-year qualitative study examined how 26 teachers in four U.S. secondary schools addressed the literacy demands of curriculum materials based on standards from the National Council of Teachers of Mathematics. It was grounded in sociocultural perspectives that encourage study of language in local contexts, including classrooms, communities,…
ERIC Educational Resources Information Center
Llewellyn, Gerald C.; And Others
Classroom tested ideas and resources for social studies and science teachers on toxic and hazardous substances are provided in this guide. Suggestions are included for ways of increasing student awareness and knowledge about this problem. Although the materials were primarily developed for junior high students they can be adapted and modified for…
NASA Technical Reports Server (NTRS)
Bast, Callie C.; Boyce, Lola
1995-01-01
This report presents the results of both the fifth and sixth year effort of a research program conducted for NASA-LeRC by The University of Texas at San Antonio (UTSA). The research included on-going development of methodology for a probabilistic material strength degradation model. The probabilistic model, in the form of a postulated randomized multifactor equation, provides for quantification of uncertainty in the lifetime material strength of aerospace propulsion system components subjected to a number of diverse random effects. This model is embodied in the computer program entitled PROMISS, which can include up to eighteen different effects. Presently, the model includes five effects that typically reduce lifetime strength: high temperature, high-cycle mechanical fatigue, low-cycle mechanical fatigue, creep and thermal fatigue. Statistical analysis was conducted on experimental Inconel 718 data obtained from the open literature. This analysis provided regression parameters for use as the model's empirical material constants, thus calibrating the model specifically for Inconel 718. Model calibration was carried out for five variables, namely, high temperature, high-cycle and low-cycle mechanical fatigue, creep and thermal fatigue. Methodology to estimate standard deviations of these material constants for input into the probabilistic material strength model was developed. Using an updated version of PROMISS, entitled PROMISS93, a sensitivity study for the combined effects of high-cycle mechanical fatigue, creep and thermal fatigue was performed. Then using the current version of PROMISS, entitled PROMISS94, a second sensitivity study including the effect of low-cycle mechanical fatigue, as well as, the three previous effects was performed. Results, in the form of cumulative distribution functions, illustrated the sensitivity of lifetime strength to any current value of an effect. In addition, verification studies comparing a combination of high-cycle mechanical fatigue and high temperature effects by model to the combination by experiment were conducted. Thus, for Inconel 718, the basic model assumption of independence between effects was evaluated. Results from this limited verification study strongly supported this assumption.
Williams, Andrew M; Muir, Kelly W; Rosdahl, Jullia A
2016-08-03
Patient education materials should be written at a level that is understandable for patients with low health literacy. The aims of this study are (1) to review the literature on readability of ophthalmic patient education materials and (2) to evaluate and revise our institution's patient education materials about glaucoma using evidence-based guidelines on writing for patients with low health literacy. A systematic search was conducted on the PubMed/MEDLINE database for studies that have evaluated readability level of ophthalmic patient education materials, and the reported readability scores were assessed. Additionally, we collected evidence-based guidelines for writing easy-to-read patient education materials, and these recommendations were applied to revise 12 patient education handouts on various glaucoma topics at our institution. Readability measures, including Flesch-Kincaid Grade Level (FKGL), and word count were calculated for the original and revised documents. The original and revised versions of the handouts were then scored in random order by two glaucoma specialists using the Suitability Assessment of Materials (SAM) instrument, a grading scale used to evaluate suitability of health information materials for patients. Paired t test was used to analyze changes in readability measures, word count, and SAM score between original and revised handouts. Finally, five glaucoma patients were interviewed to discuss the revised materials, and patient feedback was analyzed qualitatively. Our literature search included 13 studies that evaluated a total of 950 educational materials. Among the mean FKGL readability scores reported in these studies, the median was 11 (representing an eleventh-grade reading level). At our institution, handouts' readability averaged a tenth-grade reading level (FKGL = 10.0 ± 1.6), but revising the handouts improved their readability to a sixth-grade reading level (FKGL = 6.4 ± 1.2) (p < 0.001). Additionally, the mean SAM score of our institution's handouts improved from 60 ± 7 % (adequate) for the original versions to 88 ± 4 % (superior) for the revised handouts (p < 0.001). Our systematic review of the literature reveals that ophthalmic patient education materials are consistently written at a level that is too high for many patients to understand. Our institution's experience suggests that applying guidelines on writing easy-to-understand material can improve the readability and suitability of educational materials for patients with low health literacy.
Wang, Lin-Yan; Tang, Yu-Ping; Liu, Xin; Ge, Ya-Hui; Li, Shu-Jiao; Shang, Er-Xin; Duan, Jin-Ao
2014-04-01
To establish a method for studying efficacious materials of traditional Chinese medicines from an overall perspective. Carthamus tinctorius was taken the example. Its major components were depleted by preparing liquid chromatography. Afterwards, the samples with major components depleted were evaluated for their antioxidant effect, so as to compare and analyze the major efficacious materials of C. tinctorius with antioxidant activity and the contributions. Seven major components were depleted from C. tinctorius samples, and six of them were identified with MS data and control comparison. After all of the samples including depleted materials are compared and evaluated for their antioxidant effect, the findings showed that hydroxysafflor yellow A, anhydrosafflor yellow B and 6-hydroxykaempferol-3, 6-di-O-glucoside-7-O-glucuronide were the major efficacious materials. This study explored a novel and effective method for studying efficacious materials of traditional Chinese medicines. Through this method, we could explain the direct and indirect contributions of different components to the efficacy of traditional Chinese medicines, and make the efficacious material expression of traditional Chinese medicines clearer.
The paper discusses methods for characterizing chemical emissions from material sources, including laboratory, dynamic chamber, and full-scale studies. Indoor sources and their interaction with sinks play a major role in determining indoor air quality (IAQ). Techniques for evalua...
ERIC Educational Resources Information Center
Marine Corps Inst., Washington, DC.
Developed as part of the Marine Corps Institute (MCI) correspondence training program, this course on pastry baking is designed to provide a source of study materials on the preparation of pastry items within central pastry shops throughout the Marine Corps; it is adaptable for nonmilitary instruction. Introductory materials include specific…
ERIC Educational Resources Information Center
Minnesota State Dept. of Natural Resources, St. Paul. Environmental Education Board.
Eight energy education activities are provided. Each activity includes an overview, a brief summary, lists of objectives and materials needed, teacher's notes, and student materials. The activities focus on: (1) using social studies skills to understand Minnesota energy data and to clarify and understand some Minnesota energy issues; (2) giving…
Australia: An Instructional Unit for Elementary Grades.
ERIC Educational Resources Information Center
Duea, Joan; And Others
Designed to provide elementary teachers with materials for the study of Australia, this unit contains 19 lessons that include objectives, materials, procedures, suggested extension activities, and answer keys where needed. Following the 19 lessons are blackline masters for teacher transparencies, student worksheets, and extension activities. A…
A Selection of Composites Simulation Practices at NASA Langley Research Center
NASA Technical Reports Server (NTRS)
Ratcliffe, James G.
2007-01-01
One of the major areas of study at NASA Langley Research Center is the development of technologies that support the use of advanced composite materials in aerospace applications. Amongst the supporting technologies are analysis tools used to simulate the behavior of these materials. This presentation will discuss a number of examples of analysis tools and simulation practices conducted at NASA Langley. The presentation will include examples of damage tolerance analyses for both interlaminar and intralaminar failure modes. Tools for modeling interlaminar failure modes include fracture mechanics and cohesive methods, whilst tools for modeling intralaminar failure involve the development of various progressive failure analyses. Other examples of analyses developed at NASA Langley include a thermo-mechanical model of an orthotropic material and the simulation of delamination growth in z-pin reinforced laminates.
NASA Technical Reports Server (NTRS)
Bast, Callie C.; Boyce, Lola
1995-01-01
The development of methodology for a probabilistic material strength degradation is described. The probabilistic model, in the form of a postulated randomized multifactor equation, provides for quantification of uncertainty in the lifetime material strength of aerospace propulsion system components subjected to a number of diverse random effects. This model is embodied in the computer program entitled PROMISS, which can include up to eighteen different effects. Presently, the model includes five effects that typically reduce lifetime strength: high temperature, high-cycle mechanical fatigue, low-cycle mechanical fatigue, creep and thermal fatigue. Results, in the form of cumulative distribution functions, illustrated the sensitivity of lifetime strength to any current value of an effect. In addition, verification studies comparing predictions of high-cycle mechanical fatigue and high temperature effects with experiments are presented. Results from this limited verification study strongly supported that material degradation can be represented by randomized multifactor interaction models.
Impact damage resistance of composite fuselage structure, part 1
NASA Technical Reports Server (NTRS)
Dost, E. F.; Avery, W. B.; Ilcewicz, L. B.; Grande, D. H.; Coxon, B. R.
1992-01-01
The impact damage resistance of laminated composite transport aircraft fuselage structures was studied experimentally. A statistically based designed experiment was used to examine numerous material, laminate, structural, and extrinsic (e.g., impactor type) variables. The relative importance and quantitative measure of the effect of each variable and variable interactions on responses including impactor dynamic response, visibility, and internal damage state were determined. The study utilized 32 three-stiffener panels, each with a unique combination of material type, material forms, and structural geometry. Two manufacturing techniques, tow placement and tape lamination, were used to build panels representative of potential fuselage crown, keel, and lower side-panel designs. Various combinations of impactor variables representing various foreign-object-impact threats to the aircraft were examined. Impacts performed at different structural locations within each panel (e.g., skin midbay, stiffener attaching flange, etc.) were considered separate parallel experiments. The relationship between input variables, measured damage states, and structural response to this damage are presented including recommendations for materials and impact test methods for fuselage structure.
Phase Equilibrium and Crystal Growth Studies on AgGaSe2 and Related Nonlinear Optical Materials
1989-09-01
identify by block number) IELD GROUP SUB-GROUP - "°Silver selenogallate, AgGaSe2, nonlinear optical materials, infrared materials, optical defects 19...materials has unique nonlinear infrared optical properties( 1-4 ) including high nonlinear coefficients, and the ability to be phase matched through a...have a milky appearance in thin section or when viewed with a commercial infrared image converter. Microscopic examination of AgGaSe2 in both reflected
Gas storage materials, including hydrogen storage materials
Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji
2013-02-19
A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.
Gas storage materials, including hydrogen storage materials
Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji
2014-11-25
A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material, such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.
Article and process for producing an article
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lacy, Benjamin Paul; Jacala, Ariel Caesar Prepena; Kottilingam, Srikanth Chandrudu
An article and a process of producing an article are provided. The article includes a base material, a cooling feature arrangement positioned on the base material, the cooling feature arrangement including an additive-structured material, and a cover material. The cooling feature arrangement is between the base material and the cover material. The process of producing the article includes manufacturing a cooling feature arrangement by an additive manufacturing technique, and then positioning the cooling feature arrangement between a base material and a cover material.
Allergic Reactions to Dental Materials-A Systematic Review
Chopra, Radhika; Sachdev, Vinod
2015-01-01
Introduction Utility of various dental materials ranging from diagnosis to rehabilitation for the management of oral diseases are not devoid of posing a potential risk of inducing allergic reactions to the patient, technician and dentist. This review aims to develop a systematic approach for the selection and monitoring of dental materials available in the market thereby giving an insight to predict their risk of inducing allergic reactions. Materials and Methods Our data included 71 relevant articles which included 60 case reports, 8 prospective studies and 3 retrospective studies. The source of these articles was Pub Med search done with the following terms: allergies to impression materials, sodium hypochlorite, Ledermix paste, zinc oxide eugenol, formaldehyde, Latex gloves, Methyl methacrylate, fissure sealant, composites, mercury, Nickel-chromium, Titanium, polishing paste and local anaesthesia. All the relevant articles and their references were analysed. The clinical manifestations of allergy to different dental materials based on different case reports were reviewed. Results After reviewing the literature, we found that the dental material reported to cause most adverse reactions in patients is amalgam and the incidence of oral lichenoid reactions adjacent to amalgam restorations occur more often than other dental materials. Conclusion The most common allergic reactions in dental staff are allergies to latex, acrylates and formaldehyde. While polymethylmethacrylates and latex trigger delayed hypersensitivity reactions, sodium metabisulphite and nickel cause immediate reactions. Over the last few years, due to the rise in number of patients with allergies from different materials, the practicing dentists should have knowledge about documented allergies to known materials and thus avoid such allergic manifestations in the dental clinic. PMID:26557634
Prevalence and distribution of dental restorative materials in US Air Force veterans.
Albertini, T F; Kingman, A; Brown, L J
1997-01-01
Millions of restorative procedures are performed annually in the United States, yet very little is known about their distribution in the general population. With increasing concern about potential adverse health effects of some restorative materials, a better understanding of the extent of exposure to these materials in the population is important. The purpose of this study is to report the prevalence, patterns, and distribution of dental restorative materials in a population of male veterans. This collaborative study with the US Air Force examined 1,166 male veterans to assess exposure to dental amalgam and other restorative materials. An inventory of dental materials in the study population was obtained through oral examinations. Dental materials were classified into five categories: (1) amalgam; (2) resin; (3) porcelain, cement, or temporary, including ionomer (PCT); (4) cast gold alloys/direct filling gold; and (5) other metals (OM). The mean age of the study participants was 52.9 years. Over 94 percent of the study participants were dentate. The study participants averaged 45.8 restored/replaced surfaces. Restored/replaced surfaces increased with age while the number of teeth decreased with age. The most frequently used restorative material was amalgam, averaging 19.89 surfaces per subject, followed by PCT (9.38), resins (8.99), OM (5.52), and gold (4.91). The distributions of restorative materials varied by age, arch type, and location in the mouth. The study population experienced substantial exposure to dental materials.
Low transient thermal stress turbine engine components
Shi, Jun [Glastonbury, CT; Schmidt, Wayde R [Pomfret Center, CT
2011-06-28
A turbine vane includes a platform; and at least one airfoil mounted to the platform and having a trailing edge and a leading edge, wherein the vane is composed of a functionally graded material having a first material and a second material, wherein the trailing edge includes a greater amount of the first material than the second material, and the leading edge includes a greater amount of the second material than the first material.
Polyphosphazine-based polymer materials
Fox, Robert V.; Avci, Recep; Groenewold, Gary S.
2010-05-25
Methods of removing contaminant matter from porous materials include applying a polymer material to a contaminated surface, irradiating the contaminated surface to cause redistribution of contaminant matter, and removing at least a portion of the polymer material from the surface. Systems for decontaminating a contaminated structure comprising porous material include a radiation device configured to emit electromagnetic radiation toward a surface of a structure, and at least one spray device configured to apply a capture material onto the surface of the structure. Polymer materials that can be used in such methods and systems include polyphosphazine-based polymer materials having polyphosphazine backbone segments and side chain groups that include selected functional groups. The selected functional groups may include iminos, oximes, carboxylates, sulfonates, .beta.-diketones, phosphine sulfides, phosphates, phosphites, phosphonates, phosphinates, phosphine oxides, monothio phosphinic acids, and dithio phosphinic acids.
Development and testing of a superconducting link for an IR detector
NASA Technical Reports Server (NTRS)
Caton, R.; Selim, R.
1991-01-01
The development and testing of a ceramic superconducting link for an infrared detector is summarized. Areas of study included the materials used, the electrical contacts, radiation and temperature cycling effects, aging, thermal conductivity, and computer models of an ideal link. Materials' samples were processed in a tube furnace at temperatures of 840 C to 865 C for periods up to 17 days and transition temperatures and critical current densities were recorded. The project achieved better quality high superconducting transition temperature material through improved processing and also achieved high quality electrical contacts. Studies on effects of electron irradiation, temperature cycling, and aging on superconducting properties indicate that the materials will be suitable for space applications. Various presentations and publications on the study's results are reported.
Park, Jun-Sang; Zhang, Xuan; Kenesei, Peter; ...
2017-08-31
A suite of non-destructive, three-dimensional X-ray microscopy techniques have recently been developed and used to characterize the microstructures of polycrystalline materials. These techniques utilize high-energy synchrotron radiation and include near-field and far-field diffraction microscopy (NF- and FF-HEDM, respectively) and absorption tomography. Several compatible sample environments have also been developed, enabling a wide range of 3D studies of material evolution. In this article, the FF-HEDM technique is described in detail, including its implementation at the 1-ID beamline of the Advanced Photon Source. Examples of how the information obtained from FF-HEDM can be used to deepen our understanding of structure-property-processing relationships inmore » selected materials are presented.« less
Compatibility of refractory materials for nuclear reactor poison control systems
NASA Technical Reports Server (NTRS)
Sinclair, J. H.
1974-01-01
Metal-clad poison rods have been considered for the control system of an advanced space power reactor concept studied at the NASA Lewis Research Center. Such control rods may be required to operate at temperatures of about 140O C. Selected poison materials (including boron carbide and the diborides of zirconium, hafnium, and tantalum) were subjected to 1000-hour screening tests in contact with candidate refractory metal cladding materials (including tungsten and alloys of tantalum, niobium, and molybdenum) to assess the compatibility of these materials combinations at the temperatures of interest. Zirconium and hafnium diborides were compatible with refractory metals at 1400 C, but boron carbide and tantalum diboride reacted with the refractory metals at this temperature. Zirconium diboride also showed promise as a reaction barrier between boron carbide and tungsten.
The study of radiation effects in emerging micro and nano electro mechanical systems (M and NEMs)
NASA Astrophysics Data System (ADS)
Arutt, Charles N.; Alles, Michael L.; Liao, Wenjun; Gong, Huiqi; Davidson, Jim L.; Schrimpf, Ronald D.; Reed, Robert A.; Weller, Robert A.; Bolotin, Kirill; Nicholl, Ryan; Pham, Thang Toan; Zettl, Alex; Qingyang, Du; Hu, Juejun; Li, Mo; Alphenaar, Bruce W.; Lin, Ji-Tzuoh; Shurva, Pranoy Deb; McNamara, Shamus; Walsh, Kevin M.; X-L Feng, Philip; Hutin, Louis; Ernst, Thomas; Homeijer, Brian D.; Polcawich, Ronald G.; Proie, Robert M.; Jones, Jacob L.; Glaser, Evan R.; Cress, Cory D.; Bassiri-Gharb, Nazanin
2017-01-01
The potential of micro and nano electromechanical systems (M and NEMS) has expanded due to advances in materials and fabrication processes. A wide variety of materials are now being pursued and deployed for M and NEMS including silicon carbide (SiC), III-V materials, thin-film piezoelectric and ferroelectric, electro-optical and 2D atomic crystals such as graphene, hexagonal boron nitride (h-BN), and molybdenum disulfide (MoS2). The miniaturization, functionality and low-power operation offered by these types of devices are attractive for many application areas including physical sciences, medical, space and military uses, where exposure to radiation is a reliability consideration. Understanding the impact of radiation on these materials and devices is necessary for applications in radiation environments.
Numerical studies of the deposition of material released from fixed and rotary wing aircraft
NASA Technical Reports Server (NTRS)
Bilanin, A. J.; Teske, M. E.
1984-01-01
The computer code AGDISP (AGricultural DISPersal) has been developed to predict the deposition of material released from fixed and rotary wing aircraft in a single-pass, computationally efficient manner. The formulation of the code is novel in that the mean particle trajectory and the variance about the mean resulting from turbulent fluid fluctuations are simultaneously predicted. The code presently includes the capability of assessing the influence of neutral atmospheric conditions, inviscid wake vortices, particle evaporation, plant canopy and terrain on the deposition pattern. In this report, the equations governing the motion of aerially released particles are developed, including a description of the evaporation model used. A series of case studies, using AGDISP, are included.
NASA Technical Reports Server (NTRS)
Starke, E. A., Jr.
1997-01-01
This is the final report of the study "Aluminum-Based Materials for High Speed Aircraft" which had the objectives (1) to identify the most promising aluminum-based materials with respect to major structural use on the HSCT and to further develop those materials and (2) to assess the materials through detailed trade and evaluation studies with respect to their structural efficiency on the HSCT. The research team consisted of ALCOA, Allied-Signal, Boeing, McDonnell Douglas, Reynolds Metals and the University of Virginia. Four classes of aluminum alloys were investigated: (1) I/M 2XXX containing Li and I/M 2XXX without Li, (2) I/M 6XXX, (3) two P/M 2XXX alloys, and (4) two different aluminum-based metal matrix composites (MMC). The I/M alloys were targeted for a Mach 2.0 aircraft and the P/M and MMC alloys were targeted for a Mach 2.4 aircraft. Design studies were conducted using several different concepts including skin/stiffener (baseline), honeycomb sandwich, integrally stiffened and hybrid adaptations (conventionally stiffened thin-sandwich skins). Alloy development included fundamental studies of coarsening behavior, the effect of stress on nucleation and growth of precipitates, and fracture toughness as a function of temperature were an integral part of this program. The details of all phases of the research are described in this final report.
Leung, Ting-Kai; Kuo, Chia-Hua; Lee, Chi-Ming; Kan, Nai-Wen; Hou, Chien-Wen
2013-12-31
Previous biomolecular and animal studies have shown that a room-temperature far-infrared-rayemitting ceramic material (bioceramic) demonstrates physical-biological effects, including the normalization of psychologically induced stress-conditioned elevated heart rate in animals. In this clinical study, the Harvard step test, the resting metabolic rate (RMR) assessment and the treadmill running test were conducted to evaluate possible physiological effects of the bioceramic material in human patients. The analysis of heart rate variability (HRV) during the Harvard step test indicated that the bioceramic material significantly increased the high-frequency (HF) power spectrum. In addition, the results of RMR analysis suggest that the bioceramic material reduced oxygen consumption (VO2). Our results demonstrate that the bioceramic material has the tendency to stimulate parasympathetic responses, which may reduce resting energy expenditure and improve cardiorespiratory recovery following exercise.
USDA-ARS?s Scientific Manuscript database
We used a portable hyperspectral fluorescence imaging system to evaluate biofilm formations on four types of food processing surface materials including stainless steel, polypropylene used for cutting boards, and household counter top materials such as formica and granite. The objective of this inve...
Exploring Technology Education: Exploring Communication Technology.
ERIC Educational Resources Information Center
Joerschke, John D.
These instructional materials include a teacher's guide designed to assist instructors in organizing and presenting a unit of study on communication technology and a student guide. The materials are based on the curriculum-alignment concept of first stating the objectives, developing instructional strategies for teaching those objectives, and then…
ERIC Educational Resources Information Center
Rowe, Sue Ellen, Comp.
Audiovisual materials suitable for the teaching of nutrition are listed. Materials include coloring books, flannelboard stories, games, kits, audiotapes, records, charts, posters, study prints, films, videotapes, filmstrips, slides, and transparencies. Each entry contains bibliographic data, educational level, price and evaluation. Mateiral is…
The Mass Spectrometric Ortho Effect Studied for All 209 PCB Congeners
A method for the determination of polychlorinated biphenyls (PCBs) in caulk was developed; with application to a set of caulk and window glazing material samples. This method was evaluated by analyzing a combination of 47 samples of caulk, glazing materials, and including quality...
Exploring Technology Education: Exploring Manufacturing Technology.
ERIC Educational Resources Information Center
Joerschke, John D.
These instructional materials include a teacher's guide designed to assist instructors in organizing and presenting a unit of study on manufacturing technology and a student guide. The materials are based on the curriculum-alignment concept of first stating the objectives, developing instructional strategies for teaching those objectives, and then…
Using Aquatic Insects as Indicators of Water Quality
ERIC Educational Resources Information Center
Dyche, Steven E.
1977-01-01
Described is a science field activity that studies the presence of certain aquatic insects, like stoneflies, as indicators of water quality. Equipment, materials, and methods are listed in detail, including suggestions for building certain supplies. Results of previous studies on the Yellowstone River are included. (MA)
ERIC Educational Resources Information Center
Hallowell, Anne; And Others
This study guide was designed to help teachers and students understand the problems surrounding solid wastes. It includes an overview of solid waste and recycling, a glossary, suggested activities and a list of resource publications, audiovisual materials and organizations. There are 19 activity suggestions included in this guide designed for use…
Tripathy, Ashis; Pramanik, Sumit; Cho, Jongman; Santhosh, Jayasree; Osman, Noor Azuan Abu
2014-01-01
The humidity sensing characteristics of different sensing materials are important properties in order to monitor different products or events in a wide range of industrial sectors, research and development laboratories as well as daily life. The primary aim of this study is to compare the sensing characteristics, including impedance or resistance, capacitance, hysteresis, recovery and response times, and stability with respect to relative humidity, frequency, and temperature, of different materials. Various materials, including ceramics, semiconductors, and polymers, used for sensing relative humidity have been reviewed. Correlations of the different electrical characteristics of different doped sensor materials as the most unique feature of a material have been noted. The electrical properties of different sensor materials are found to change significantly with the morphological changes, doping concentration of different materials and film thickness of the substrate. Various applications and scopes are pointed out in the review article. We extensively reviewed almost all main kinds of relative humidity sensors and how their electrical characteristics vary with different doping concentrations, film thickness and basic sensing materials. Based on statistical tests, the zinc oxide-based sensing material is best for humidity sensor design since it shows extremely low hysteresis loss, minimum response and recovery times and excellent stability. PMID:25256110
Dorado, A D; Lafuente, F J; Gabriel, D; Gamisans, X
2010-02-01
In the present work, 10 packing materials commonly used as support media in biofiltration are analysed and compared to evaluate their suitability according to physical characteristics. The nature of the packing material in biofilters is an important factor for the success in their construction and operation. Different packing materials have been used in biofiltration without a global agreement about which ones are the most adequate for biofiltration success. The materials studied were chosen according to previous works in the field of biofiltration including both organic and inorganic (or synthetic) materials. A set of nine different parameters were selected to cope with well-established factors, such as a material-specific surface area, pressure drop, nutrient supply, water retentivity, sorption capacity, and purchase cost. One ranking of packing materials was established for each parameter studied in order to define a relative suitability degree. Since biofiltration success generally depends on a combination of the ranked parameters, a procedure was defined to compare packing materials suitability under common situations in biofiltration. The selected scenarios, such as biofiltration of intermittent loads of pollutants and biofiltration of waste gases with low relative humidity, were investigated. The results indicate that, out of the packing materials studied, activated carbons were ranked top of several parameter rankings and were shown to be a significantly better packing material when parameters were combined to assess such selected scenarios.
Combustion interaction with radiation-cooled chambers
NASA Technical Reports Server (NTRS)
Rosenberg, S. D.; Jassowski, D. M.; Barlow, R.; Lucht, R.; Mccarty, K.
1990-01-01
Over 15 hours of thruster operation at temperatures between 1916 and 2246 C without failure or erosion has been demonstrated using iridium-coated rhenium chamber materials with nitrogen tetroxide/monomethylhydrazine propellants operating over a mixture ratio range of 1.60-2.05. Research is now under way to provide a basic understanding of the mechanisms which make high-temperature operation possible and to extend the capability to a wider range of conditions, including other propellant combinations and chamber materials. Techniques have been demonstrated for studying surface fracture phenomena. These include surface Raman and Auger for study of oxide formation, surface Raman and X-ray diffraction to determine the oxide phase, Auger to study oxide stoichiometry, and sputter Auger to study interdiffusion of alloy species.
Foreign body aspiration in dentistry: a review.
Cameron, S M; Whitlock, W L; Tabor, M S
1996-08-01
This article reviews the dangers of aspirating foreign bodies of dental origin. Two illustrative cases are presented, including an unusual case involving aspiration of an elastomeric impression material. The authors describe the techniques used to identify the foreign body. A radiodensimetric study of four impression materials demonstrates the difficulty of identifying most impression materials. The authors also present some strategies for reducing the risk of aspiration during dental procedures.
ERIC Educational Resources Information Center
Tsekleves, Emmanuel; Aggoun, Amar; Cosmas, John
2013-01-01
This research study explores the use of different lab material, investigating which types of materials contribute the most to the delivery and support of laboratory (lab) sessions to design, skill-based and technical courses in higher education in the UK. A qualitative research methodology was employed for this investigation and included both key…
ERIC Educational Resources Information Center
Roberts, Douglas A.
This booklet is designed to supplement the study of introductory chemistry. It deals particularly with the mole concept but also includes ideas for analyzing the kinds of statements that appear in all science textbooks and scientific writing. The material in the booklet should be studied after the completion of an introductory textbook study of…
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
1975-09-30
Studies of reactions between core materials and coolant impurities, basic fission product transport mechanisms, core graphite development and testing, the development and testing of recyclable fuel systems, and physics and fuel management studies are described. Materials studies include irradiation capsule tests of both fuel and graphite. Experimental procedures and results are discussed and, where appropriate, the data are presented in tables, graphs, and photographs. (auth)
Development of accurate potentials to explore the structure of water on 2D materials
NASA Astrophysics Data System (ADS)
Bejagam, Karteek; Singh, Samrendra; Deshmukh, Sanket; Deshmkuh Group Team; Samrendra Group Collaboration
Water play an important role in many biological and non-biological process. Thus structure of water at various interfaces and under confinement has always been the topic of immense interest. 2-D materials have shown great potential in surface coating applications and nanofluidic devices. However, the exact atomic level understanding of the wettability of single layer of these 2-D materials is still lacking mainly due to lack of experimental techniques and computational methodologies including accurate force-field potentials and algorithms to measure the contact angle of water. In the present study, we have developed a new algorithm to measure the accurate contact angle between water and 2-D materials. The algorithm is based on fitting the best sphere to the shape of the droplet. This novel spherical fitting method accounts for every individual molecule of the droplet, rather than those at the surface only. We employ this method of contact angle measurements to develop the accurate non-bonded potentials between water and 2-D materials including graphene and boron nitride (BN) to reproduce the experimentally observed contact angle of water on these 2-D materials. Different water models such as SPC, SPC/Fw, and TIP3P were used to study the structure of water at the interfaces.
Methods for removing contaminant matter from a porous material
Fox, Robert V [Idaho Falls, ID; Avci, Recep [Bozeman, MT; Groenewold, Gary S [Idaho Falls, ID
2010-11-16
Methods of removing contaminant matter from porous materials include applying a polymer material to a contaminated surface, irradiating the contaminated surface to cause redistribution of contaminant matter, and removing at least a portion of the polymer material from the surface. Systems for decontaminating a contaminated structure comprising porous material include a radiation device configured to emit electromagnetic radiation toward a surface of a structure, and at least one spray device configured to apply a capture material onto the surface of the structure. Polymer materials that can be used in such methods and systems include polyphosphazine-based polymer materials having polyphosphazine backbone segments and side chain groups that include selected functional groups. The selected functional groups may include iminos, oximes, carboxylates, sulfonates, .beta.-diketones, phosphine sulfides, phosphates, phosphites, phosphonates, phosphinates, phosphine oxides, monothio phosphinic acids, and dithio phosphinic acids.
Materials with structural hierarchy
NASA Technical Reports Server (NTRS)
Lakes, Roderic
1993-01-01
The role of structural hierarchy in determining bulk material properties is examined. Dense hierarchical materials are discussed, including composites and polycrystals, polymers, and biological materials. Hierarchical cellular materials are considered, including cellular solids and the prediction of strength and stiffness in hierarchical cellular materials.
Shear Induced Structural Relaxation in a Supercooled Colloidal Liquid
NASA Astrophysics Data System (ADS)
Chen, Dandan; Semwogerere, Denis; Weeks, Eric R.
2009-11-01
Amorphous materials include many common products we use everyday, such as window glass, moisturizer, shaving cream and peanut butter. These materials have liquid-like disordered structure, but keep their shapes like a solid. The rheology of dense amorphous materials under large shear strain is not fully understood, partly due to the difficulty of directly viewing the microscopic details of such materials. We use a colloidal suspension to simulate amorphous materials, and study the shear- induced structural relaxation with fast confocal microscopy. We quantify the plastic rearrangements of the particles using standard analysis techniques based on the motion of the particles.
Energy Education Materials Inventory (e.e.m.i.). Part One: Print Materials.
ERIC Educational Resources Information Center
Energy and Man's Environment, Inc., Portland, OR.
This publication is one of a six-part inventory of energy education materials. Included in this part is a listing of print materials, including the following: teacher's guides, curriculum guides, ditto masters, textbooks, pamphlets, and posters. For each of the materials listed, the following information is included when available: (1) Title; (2)…
Liquid crystalline epoxy nanocomposite material for dental application.
Tai, Yun-Yuan; Hsu, Sheng-Hao; Chen, Rung-Shu; Su, Wei-Fang; Chen, Min-Huey
2015-01-01
Novel liquid crystalline epoxy nanocomposites, which exhibit reduced polymerization shrinkage and effectively bond to tooth structures, can be applied in esthetic dentistry, including core and post systems, direct and indirect restorations, and dental brackets. The purposes of this study were to investigate the properties of liquid crystalline epoxy nanocomposites including biocompatibility, microhardness, and frictional forces of bracket-like blocks with different filler contents for further clinical applications. In this study, we evaluated liquid crystalline epoxy nanocomposite materials that exhibited various filler contents, by assessing their cell activity performance using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and their microhardness with or without thermocycling. We also evaluated the frictional force between bracket-like duplicates and commercially available esthetic bracket systems using Instron 5566. The liquid crystalline epoxy nanocomposite materials showed good biocompatibility. The materials having high filler content demonstrated greater microhardness compared with commercially available bracket materials, before and after the thermocycling treatment. Thus, manufacturing processes are important to reduce frictional force experienced by orthodontic brackets. The microhardness of the bracket-like blocks made by our new material is superior to the commercially available brackets, even after thermocycling. Our results indicate that the evaluated liquid crystalline epoxy nanocomposite materials are of an appropriate quality for application in dental core and post systems and in various restorations. By applying technology to refine manufacturing processes, these new materials could also be used to fabricate esthetic brackets for orthodontic treatment. Copyright © 2014. Published by Elsevier B.V.
Hutchens, Stacy A [Knoxville, TN; Woodward, Jonathan [Solihull, GB; Evans, Barbara R [Oak Ridge, TN; O'Neill, Hugh M [Knoxville, TN
2012-02-07
A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.
Semiconductor structure and recess formation etch technique
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lu, Bin; Sun, Min; Palacios, Tomas Apostol
2017-02-14
A semiconductor structure has a first layer that includes a first semiconductor material and a second layer that includes a second semiconductor material. The first semiconductor material is selectively etchable over the second semiconductor material using a first etching process. The first layer is disposed over the second layer. A recess is disposed at least in the first layer. Also described is a method of forming a semiconductor structure that includes a recess. The method includes etching a region in a first layer using a first etching process. The first layer includes a first semiconductor material. The first etching processmore » stops at a second layer beneath the first layer. The second layer includes a second semiconductor material.« less
Comparative analysis of print and multimedia health materials: a review of the literature.
Wilson, Elizabeth A H; Makoul, Gregory; Bojarski, Elizabeth A; Bailey, Stacy Cooper; Waite, Katherine R; Rapp, David N; Baker, David W; Wolf, Michael S
2012-10-01
Evaluate the evidence regarding the relative effectiveness of multimedia and print as modes of dissemination for patient education materials; examine whether development of these materials addressed health literacy. A structured literature review utilizing Medline, PsycInfo, and the Cumulative Index to the Nursing and Allied Health Literature (CINAHL), supplemented by reference mining. Of 738 studies screened, 30 effectively compared multimedia and print materials. Studies offered 56 opportunities for assessing the effect of medium on various outcomes (e.g., knowledge). In 30 instances (54%), no difference was noted between multimedia and print in terms of patient outcomes. Multimedia led to better outcomes vs. print in 21 (38%) comparisons vs. 5 (9%) instances for print. Regarding material development, 12 studies (40%) assessed readability and 5 (17%) involved patients in tool development. Multimedia appears to be a promising medium for patient education; however, the majority of studies found that print and multimedia performed equally well in practice. Few studies involved patients in material development, and less than half assessed the readability of materials. Future research should focus on comparing message-equivalent tools and assessing their effect on behavioral outcomes. Material development should include explicit attention to readability and patient input. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Dargaud, Jacques; Chalvet, Laurane; Del Corso, Marco; Cerboni, Elsa; Feugier, Patrick; Mertens, Patrick; Simon, Emile
2016-04-01
There are numerous injection materials for the study of vasculature in anatomical specimens, each having its own advantages and disadvantages. Latex and resins are the most widely used injection materials but need several days to set. The development of new materials taking shorter time to polymerize might be very useful to improve anatomic specimen study conditions. The aim of the present study was to evaluate vinyl polysiloxane (VPS), a silicon material widely used for dental impressions with the advantage to set very rapidly, as an injection material. We assessed the preparation, use, diffusion and setting time of the product in different anatomical regions (central nervous system, external carotid/jugular, lower limb) to observe its behavior in variably sized vessels. Our results suggest that VPS might be of interest for the study of vessels in anatomical specimens. The main strengths of the product are represented by (1) simplicity of use, as it is a ready-to-use material, (2) very rapid polymerization, (3) availability in a range of viscosities making easier the exploration of small vessels, (4) its better elasticity compared to resins, (5) and finally its availability in a range of colors making it a material of choice for vascular system dissections including those with very small caliber vessels.
Effects of Variations in Toy Presentation on Social Behaviour of Infants and Toddlers in Childcare
ERIC Educational Resources Information Center
Shohet, Cilly; Klein, Pnina S.
2010-01-01
The objective of this study was to examine the effects of variations in presentation of play materials on social behaviour of 18- to 30-month-old children. The study group included 102 children attending infant and toddler classes in 14 public childcare centres in Israel. Play materials were presented to the children either in a suggestive manner…
ERIC Educational Resources Information Center
Lucas, John A.; Magad, Eugene
In fall 1995, William Rainey Harper College in Illinois conducted a study of former students in the Materials/Logistics Management (MLM) program to determine their evaluation of their educational experiences in the program. The sample consisted of 298 former MLM students from 1990 to 1995, including 119 students who had earned 48 credit hours but…
Lin, Zhong; McCreary, Amber; Briggs, Natalie; ...
2016-12-08
The rise of two-dimensional (2D) materials research took place following the isolation of graphene in 2004. These new 2D materials include transition metal dichalcogenides, mono-elemental 2D sheets, and several carbide- and nitride-based materials. The number of publications related to these emerging materials has been drastically increasing over the last five years. Thus, through this comprehensive review, we aim to discuss the most recent groundbreaking discoveries as well as emerging opportunities and remaining challenges. This review starts out by delving into the improved methods of producing these new 2D materials via controlled exfoliation, metal organic chemical vapor deposition, and wet chemicalmore » means. Here we look into recent studies of doping as well as the optical properties of 2D materials and their heterostructures. Recent advances towards applications of these materials in 2D electronics are also reviewed, and include the tunnel MOSFET and ways to reduce the contact resistance for fabricating high-quality devices. Finally, several unique and innovative applications recently explored are discussed as well as perspectives of this exciting and fast moving field.« less
Contribution to "AIAA Aerospace Year in Review" article
NASA Technical Reports Server (NTRS)
Grugel, Richard N.; Downey, J. Patton
2012-01-01
The NASA Marshall Space Flight Center Microgravity Science Program is dedicated to promoting our understanding of materials processing by conducting relevant experiments in the microgravity environment and supporting related modeling efforts with the intent of improving ground-based practices. Currently funded investigations include research on dopant distribution and defect formation in semiconductors, microstructural development and transitions in dendritic casting alloys, coarsening phenomena, competition between thermal and kinetic phase formation, and the formation of glassy vs. crystalline material. NASA Microgravity Materials Science Principle Investigators are selected for funding either through a proposal in response to a NASA Research Announcement or by collaborating on a team that has successfully proposed to a foreign space agency research announcement. In the latter case, a US investigator can then apply to NASA for funding through an unsolicited proposal. The International Space Station (ISS) facilities used for the experimental investigations are provided primarily by partnering with foreign agencies and often US investigators are working as a part of a larger team studying a specific area of materials science. Facilities for conducting experiments aboard the ISS include the European Space Agency (ESA) Low Gradient Facility (LGF) and the Solidification and Quench (SQF) modular inserts to the Materials Research Rack/Materials Science Laboratory and are primarily used for controlled solidification studies. The French Space Agency (CNES) provided DECLIC facility allows direct observation of morphological development in transparent materials that solidify analogously to metals. The ESA provided Electro ]Magnetic Levitator (EML) is designed to levitate, melt and then cool samples in order to determine material properties, study nucleation behavior, and document phase transitions. Finally, the Microgravity Science Glovebox (MSG) serves as a onboard facility for supporting the hardware required to conduct a number of smaller, short-term investigations.
Mid-Pacific Marine Laboratory. Annual report for the period, 1 October 1977--30 September 1978
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reese, E.S.; Johnson, V.R. Jr.
1979-03-01
Studies on behavior included reproduction and sociobiology of reef fishes and aggression, hearing, and ultrasonic telemetry in sharks. Ecological studies included population, growth, and mortality studies on birds, corals, crustacea, echinoderms, fishes, molluscs, and rats. Geochemistry studies included biogeochemistry of reef organisms and hydrogeochemistry of groundwater. Geology studies included bioerosion of sea urchins, biology of endolithic processes, and survey of soils. Oceanography studies were conducted on lagoon circulation. Physiological studies were conducted on symbiosis in corals and utilization of organic material by Foraminifera. Studies on systematics of algae, echinoderms, and fishes were conducted. (HLW)
Diversity Statements: How Faculty Applicants Address Diversity
ERIC Educational Resources Information Center
Schmaling, Karen B.; Trevino, Amira Y.; Lind, Justin R.; Blume, Arthur W.; Baker, Dana L.
2015-01-01
The purpose of the present study was to examine application materials for assistant professor positions in 3 academic disciplines. Applicants were asked to write a diversity statement describing how they would advance diversity through their research, teaching, and service. The sample included application materials submitted by 191 candidates for…
Pyroelectric Ceramics for Infrared Detection Applications
NASA Technical Reports Server (NTRS)
Guggilla, Padmaja; Batra, A. K.; Currie, J. R.; Aggarwal, M. D.; Penn, B.; Lal, R. B.
2004-01-01
Pyroelectric and dielectric properties of modified PZT and PZ have been studied for their use in infrared detectors. Various material figure-of-merits for their use in infrared detector are calculated including when the pyroelectric element is placed on heat-sink condition. The results are compared with exiting candidate materials.
Self-Paced Physics, Course Materials.
ERIC Educational Resources Information Center
New York Inst. of Tech., Old Westbury.
Samples of the Self-Paced Physics Course materials are presented in this collection for dissemination purposes. Descriptions are included of course objectives, characteristics, structures, and content. As a two-semester course of study for science and engineering sophomores, most topics are on a level comparable to that of classical physics by…
Non-destructive evaluation techniques, high temperature ceramic component parts for gas turbines
NASA Technical Reports Server (NTRS)
Reiter, H.; Hirsekorn, S.; Lottermoser, J.; Goebbels, K.
1984-01-01
This report concerns studies conducted on various tests undertaken on material without destroying the material. Tests included: microradiographic techniques, vibration analysis, high-frequency ultrasonic tests with the addition of evaluation of defects and structure through analysis of ultrasonic scattering data, microwave tests and analysis of sound emission.
Kinship and Social Groups: A Modular Approach. Cultural Anthropology.
ERIC Educational Resources Information Center
Kassebaum, Peter
Designed for use as supplementary instructional material in a cultural anthropology course, this learning module introduces commonly employed terms used in the study of kinship and social groups. Conceptual categories used to describe the social structures of society are defined first, including culture, material culture, nonmaterial culture,…
ERIC Educational Resources Information Center
Eshleman, Winston Hull
Compared were programed materials and conventional methods for teaching two units of eighth grade science. Programed materials used were linear programed books requiring constructed responses. The conventional methods included textbook study, written exercises, lectures, discussions, demonstrations, experiments, chalkboard drawings, films,…
Quality and Processes of Bangladesh Open University Course Materials Development
ERIC Educational Resources Information Center
Islam, Tofazzal; Rahman, Morshedur; Rahman, K. M. Rezanur
2006-01-01
A new member of the mega-Universities, Bangladesh Open University (BOU) introduced a course team approach for developing effective course materials for distance students. BOU teaching media includes printed course books, study guides, radio and television broadcasts, audiocassettes and occasional face-to-face tutorials. Each course team…
[Science and Technology and Recycling: Instructional Materials on Aluminum.
ERIC Educational Resources Information Center
Aluminum Association, New York, NY.
Educational materials on the manufacture and use of aluminum are assembled in this multi-media unit for use by junior high and secondary school students. Student booklets and brochures include: "The Story of Aluminum,""Uses of Aluminum,""Independent Study Guide for School Research Projects,""Questions and Answers…
Recreation and scenic resources in Alaska: an annotated bibliography.
Robert M. Muth; Sally Anne Fitchet
1976-01-01
This bibliography provides descriptions of material published on recreation and scenic resources in Alaska. Included are publications on research and supporting material in the form of studies and reports, proposals, plans, historical and cultural references, bibliographic documents, and popular books and articles describing the resources of Alaska and issues relating...
Environmentally friendly processes that aid human and environmental health include recovering, recycling, and reusing limited natural resources and waste materials. In this study, we re-used Iron-rich solid waste materials from water treatment plants to synthesize magnetic iron-o...
Energy Conversion and Storage Program
NASA Astrophysics Data System (ADS)
Cairns, E. J.
1993-06-01
This report is the 1992 annual progress report for the Energy Conversion and Storage Program, a part of the Energy and Environment Division of the Lawrence Berkeley Laboratory. Work described falls into three broad areas: electrochemistry; chemical applications; and materials applications. The Energy Conversion and Storage Program applies principles of chemistry and materials science to solve problems in several areas: (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes and chemical species, and (5) study and application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis. Electrochemistry research aims to develop advanced power systems for electric vehicle and stationary energy storage applications. Chemical applications research includes topics such as separations, catalysis, fuels, and chemical analyses. Included in this program area are projects to develop improved, energy-efficient methods for processing product and waste streams from synfuel plants, coal gasifiers, and biomass conversion processes. Materials applications research includes evaluation of the properties of advanced materials, as well as development of novel preparation techniques. For example, techniques such as sputtering, laser ablation, and poised laser deposition are being used to produce high-temperature superconducting films.
An Inset CT Specimen for Evaluating Fracture in Small Samples of Material
Yahyazadehfar, M.; Nazari, A.; Kruzic, J.J.; Quinn, G.D.; Arola, D.
2013-01-01
In evaluations on the fracture behavior of hard tissues and many biomaterials, the volume of material available to study is not always sufficient to apply a standard method of practice. In the present study an inset Compact Tension (inset CT) specimen is described, which uses a small cube of material (approximately 2×2×2 mm3) that is molded within a secondary material to form the compact tension geometry. A generalized equation describing the Mode I stress intensity was developed for the specimen using the solutions from a finite element model that was defined over permissible crack lengths, variations in specimen geometry, and a range in elastic properties of the inset and mold materials. A validation of the generalized equation was performed using estimates for the fracture toughness of a commercial dental composite via the “inset CT” specimen and the standard geometry defined by ASTM E399. Results showed that the average fracture toughness obtained from the new specimen (1.23 ± 0.02 MPa•m0.5) was within 2% of that from the standard. Applications of the inset CT specimen are presented for experimental evaluations on the crack growth resistance of dental enamel and root dentin, including their fracture resistance curves. Potential errors in adopting this specimen are then discussed, including the effects of debonding between the inset and molding material on the estimated stress intensity distribution. Results of the investigation show that the inset CT specimen offers a viable approach for studying the fracture behavior of small volumes of structural materials. PMID:24268892
Haitian Component Bibliography. Migrant Heritage Studies Kit.
ERIC Educational Resources Information Center
Roark-Calnek, Sue, Comp.
This 587-item annotated bibliography, designed as a supplement to the Haitian Component of the Migrant Heritage Studies Kit, provides access to additional information, including audiovisual materials, on resources on Haiti and Haitian immigrants, published between 1877 and 1984. Part I is a "General Bibliography" which includes 313…
Social Studies Curriculum Guide: Kindergarten, 1985-86.
ERIC Educational Resources Information Center
Anderson, Lynne; And Others
This Fort Bend (Texas) social studies curriculum guide for kindergarten covers six six-week periods, and the 29 course outlines include the topics to be covered, the nine main goals and their supporting objectives, and a materials correlation key. The topics include family, the five senses, nursery rhymes, seasons, safety, holidays,…
Dender, Alma; Stagnitti, Karen
2011-02-01
There is a need for culturally appropriate assessments for Australian Indigenous children. This article reports the selection of culturally appropriate and gender-neutral play materials, and changes in administration identified to develop further the Indigenous Child-Initiated Pretend Play Assessment (I-ChIPPA). Twenty-three typically developing children aged four to six years from the Pilbara region in Western Australia participated in the study. Children were presented with four sets of play materials and frequency counts were recorded for each time the child used one of the play materials in a pretend play action. Twelve of the 23 children came to play in pairs. Both boys and girls used the Pilbara toy set including the dark coloured dolls and Pilbara region animals, more frequently than the standardised play materials from the Child-Initiated Pretend Play Assessment (ChIPPA). This study reports the first steps in the development of the I-ChIPPA. Future development will include the refinement of the administration and scoring with pairs of children, and then validity testing the assessment. © 2010 The Authors. Australian Occupational Therapy Journal © 2010 Australian Association of Occupational Therapists.
Toughened and corrosion- and wear-resistant composite structures and fabrication methods thereof
Seals, Roland D; Ripley, Edward B; Hallman, Russell L
2014-04-08
Composite structures having a reinforced material interjoined with a substrate and methods of creating a composite material interjoined with a substrate. In some embodiments the composite structure may be a line or a spot or formed by reinforced material interjoined with the substrate. The methods typically include disposing a precursor material comprising titanium diboride and/or titanium monoboride on at least a portion of the substrate and heating the precursor material and the at least a portion of the substrate in the presence of an oxidation preventative until at least a portion of the precursor material forms reinforced material interjoined with the substrate. The precursor material may be disposed on the substrate as a sheet or a tape or a slurry or a paste. Localized surface heating may be used to heat the precursor material. The reinforced material typically comprises a titanium boron compound, such as titanium monoboride, and preferably comprises .beta.-titanium. The substrate is typically titanium-bearing, iron-bearing, or aluminum-bearing. A welding rod is provided as an embodiment. The welding rod includes a metal electrode and a precursor material is disposed adjacent at least a portion of the metal electrode. A material for use in forming a composite structure is provided. The material typically includes a precursor material that includes one or more materials selected from the following group: titanium diboride and titanium monoboride. The material also typically includes a flux.
Method and apparatus for vibrating a substrate during material formation
Bailey, Jeffrey A [Richland, WA; Roger, Johnson N [Richland, WA; John, Munley T [Benton City, WA; Walter, Park R [Benton City, WA
2008-10-21
A method and apparatus for affecting the properties of a material include vibrating the material during its formation (i.e., "surface sifting"). The method includes the steps of providing a material formation device and applying a plurality of vibrations to the material during formation, which vibrations are oscillations having dissimilar, non-harmonic frequencies and at least two different directions. The apparatus includes a plurality of vibration sources that impart vibrations to the material.
Materials Characterization of Additively Manufactured Components for Rocket Propulsion
NASA Technical Reports Server (NTRS)
Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary
2015-01-01
To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRC's Additive Manufacturing roles and experimental findings will be presented.
Material Characterization of Additively Manufactured Components for Rocket Propulsion
NASA Technical Reports Server (NTRS)
Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary
2015-01-01
To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRCs Additive Manufacturing roles and experimental findings will be presented.
Acoustic levitation: recent developments and emerging opportunities in biomaterials research.
Weber, Richard J K; Benmore, Chris J; Tumber, Sonia K; Tailor, Amit N; Rey, Charles A; Taylor, Lynne S; Byrn, Stephen R
2012-04-01
Containerless sample environments (levitation) are useful for study of nucleation, supercooling, and vitrification and for synthesis of new materials, often with non-equilibrium structures. Elimination of extrinsic nucleation by container walls extends access to supercooled and supersaturated liquids under high-purity conditions. Acoustic levitation is well suited to the study of liquids including aqueous solutions, organics, soft materials, polymers, and pharmaceuticals at around room temperature. This article briefly reviews recent developments and applications of acoustic levitation in materials R&D. Examples of experiments yielding amorphous pharmaceutical materials are presented. The implementation and results of experiments on supercooled and supersaturated liquids using an acoustic levitator at a high-energy X-ray beamline are described.
Methods of measurement for semiconductor materials, process control, and devices
NASA Technical Reports Server (NTRS)
Bullis, W. M. (Editor)
1972-01-01
Activities directed toward the development of methods of measurement for semiconductor materials, process control, and devices are described. Topics investigated include: measurements of transistor delay time; application of the infrared response technique to the study of radiation-damaged, lithium-drifted silicon detectors; and identification of a condition that minimizes wire flexure and reduces the failure rate of wire bonds in transistors and integrated circuits under slow thermal cycling conditions. Supplementary data concerning staff, standards committee activities, technical services, and publications are included as appendixes.
Groher, Michael E; Crary, Michael A; Carnaby Mann, Giselle; Vickers, Zata; Aguilar, Carlos
2006-10-01
Numerous studies have suggested that the clinical evaluation of swallowing fails to adequately identify those patients who aspirate or do not aspirate on a videofluoroscopic swallowing examination. These conclusions, however, are based on comparisons between swallowed materials that were not rheologically matched. The present study used a battery of rheologically matched test materials, involving thin and thick liquids and cohesive and adhesive semisolids. Using these test items, results from a clinical swallow evaluation were compared to the results of a videofluorographic evaluation using identical test materials. Results suggest that the use of three test materials, including thin and thick liquids given in volumes of 5 and 10 ml, demonstrated the strongest associations between cough on the clinical examination and aspiration on the videofluoroscopic examination.
NASA Technical Reports Server (NTRS)
Miglionico, C.; Stein, C.; Murr, L. E.
1991-01-01
A preliminary study of materials exposed in space in LEO for nearly six years in the NASA Long-Duration Exposure Facility is presented. It is demonstrated that it will be necessary to isolate surface debris and reaction products from materials exposed in space. Replication techniques originally designed for electron microscopy examination of surfaces can be applied to lift off and isolate such surface features. Debris and reaction products were examined through a variety of analytical techniques, including the surface morphology by SEM, and internal microstructures by STEM and TEM, EDS, and SAD. The results illustrate the role that atomic oxygen and micrometeorites play in surface alteration and reaction in LEO space environments, as well as the role of debris created from other proximate materials.
Kuntz, Joshua D.; Ellsworth, German F.; Swenson, Fritz J.; Allen, Patrick G.
2017-02-21
According to one embodiment, a composite product includes: a matrix material including hexagonal boron nitride and one or more borate binders; and a plurality of cubic boron nitride particles dispersed in the matrix material. According to another embodiment, a composite product includes: a matrix material including hexagonal boron nitride and amorphous boron nitride; and a plurality of cubic boron nitride particles dispersed in the matrix material.
The Balancing Act: Meeting the Needs of All Children Including an Adolescent with Disabilities
ERIC Educational Resources Information Center
Koch, Cecelia; Mayes, Rachel
2012-01-01
Background: The aim of this study was to explore parents' experiences and strategies used when meeting the needs of all their children, including an adolescent with disabilities. Materials and methods: A qualitative study design was employed. The study was conducted in two phases. (i) Secondary analysis of ecocultural interviews with 12…
Conference on Chondrules and Their Origins
NASA Technical Reports Server (NTRS)
Hrametz, K.
1983-01-01
Chondrule parent materials, chondrule formation, and post-formational history are addressed. Contributions involving mineralogy petrology, geochemistry, geochronology, isotopic measurements, physical measurements, experimental studies, and theoretical studies are included.
NASA Astrophysics Data System (ADS)
Kopanitsa, Natalia O.
2015-01-01
In October 15-17, 2014 International Scientific Conference of Young Scientists: Advanced Materials in Construction and Engineering (TSUAB2014) took place at Tomsk State University of Architecture and Building (Tomsk, Russia). The Conference became a discussion platform for researchers in the fields of studying structure and properties of advanced building materials and included open lectures of leading scientists and oral presentations of master, postgraduate and doctoral students. A special session was devoted to reports of school children who further plan on starting a research career. The Conference included an industrial exhibition where companies displayed the products and services they supply. The companies also gave presentations of their products within the Conference sessions.
Salt Marsh Formation in the Lower Hudson River Estuary
NASA Technical Reports Server (NTRS)
Merley, Michael; Peteet, Dorothy; Hansen, James E. (Technical Monitor)
2001-01-01
Salt marshes are constant depositional environments and as a result contain accurate indicators of past relative sea level rise and salinity. The Hudson River marshes are at least twice as deep when compared to coastal marshes on either side of the mouth of the Hudson. The reason for this difference in sedimentation is unclear. This study uses macrofossil data as well as sediment stratigraphy in order to understand the formation and evolution of these marshes. The composition of seeds, roots, shoots and foraminifera, are used to indicate past sea levels. The four sites involved in this study are, from south to north, the Arthur Kill Marsh in Staten Island (40 36 N, 74 77W), Piermont marsh (N 4100; 73 55W) Croton Point (41 14 N; 73 50W) and Iona Island (41 18N, 73 58W). These are all tidally influenced but with increasing distances from the New York Bight, which gives a good spectrum of tidal influence. AMS-C14 dates on basal macrofossils will document the time of each marsh formation. Basal material from Arthur Kill (8 m) includes freshwater seeds such as Viola, Potomageton and Alnus along with Salix buds. Basal material from Croton Point (10 m) includes fibrous woody material, foraminifera and Zanichellia seeds and other brackish vegetational components. The basal material from Piermont (13.77 m) is lacking any identifiable macrofossils between 150 and 500 microns. The basal material from Iona Island (10 m) has vegetation such as Scirpus and Cyperus seeds, probably implying a brackish environment. The freshwater origin of the Arthur Kill marsh in Staten Island is significant because it predates either sea level rise or the western channel incision. Additional implications for this study include evidence for changes in river channel geomorphology. Reasons for the relatively deeper river marshes include possible basal clay compaction, high production due to river and marine nutrients as well as tectonic activity. This study provides the groundwork for more high-resolution studies of these marshes to understand the fluctuations in salinity caused by relative sea level rise, tectonic faulting and/or changes in precipitation/evaporation.
Composite materials research and education program: The NASA-Virginia Tech composites program
NASA Technical Reports Server (NTRS)
Herakovich, C. T.
1980-01-01
Major areas of study include: (1) edge effects in finite width laminated composites subjected to mechanical, thermal and hygroscopic loading with temperature dependent material properties and the influence of edge effects on the initiation of failure; (2) shear and compression testing of composite materials at room and elevated temperatures; (3) optical techniques for precise measurement of coefficients of thermal expansion of composites; (4) models for the nonlinear behavior of composites including material nonlinearity and damage accumulation and verification of the models under biaxial loading; (5) compressive failure of graphite/epoxy plates with circular holes and the buckling of composite cylinders under combined compression and torsion; (6) nonlinear mechanical properties of borsic/aluminum, graphite/polyimide and boron/aluminum; (7) the strength characteristics of spliced sandwich panels; and (8) curved graphite/epoxy panels subjected to internal pressure.
Acousto-ultrasonics to Assess Material and Structural Properties
NASA Technical Reports Server (NTRS)
Kautz, Harold E.
2002-01-01
This report was created to serve as a manual for applying the Acousto-Ultrasonic NDE method, as practiced at NASA Glenn, to the study of materials and structures for a wide range of applications. Three state of the art acousto-ultrasonic (A-U) analysis parameters, ultrasonic decay (UD) rate, mean time
Method of tissue repair using a composite material
Hutchens, Stacy A.; Woodward, Jonathan; Evans, Barbara R.; O'Neill, Hugh M.
2016-03-01
A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.
Method of tissue repair using a composite material
Hutchens, Stacy A; Woodward, Jonathan; Evans, Barbara R; O'Neill, Hugh M
2014-03-18
A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.
Schwendemanm, Irina G [Wexford, PA; Polcyn, Adam D [Pittsburgh, PA; Finley, James J [Pittsburgh, PA; Boykin, Cheri M [Kingsport, TN; Knowles, Julianna M [Apollo, PA
2011-03-15
An electrochromic device includes a first substrate spaced from a second substrate. A first conductive member is formed over at least a portion of the first substrate. A first electrochromic material is formed over at least a portion of the first conductive member. The first electrochromic material includes an organic material. A second conductive member is formed over at least a portion of the second substrate. A second electrochromic material is formed over at least a portion of the second conductive member. The second electrochromic material includes an inorganic material. An ionic liquid is positioned between the first electrochromic material and the second electrochromic material.
NASA Astrophysics Data System (ADS)
Nichols, M.; Bartolone, L.; Baldassari, C.; Hoyer-Winfield, S.
2011-09-01
The Interstellar Boundary Explorer (IBEX) mission includes a comprehensive EPO program in astronomy and heliophysics that is overseen and implemented by the Adler Planetarium in Chicago, Illinois. Several EPO components were developed specifically for informal institutions, especially museums and planetaria. The program includes an internationally distributed planetarium show with accompanying informal educational materials. Our evaluator, the Program Evaluation and Research Group (PERG) at Lesley University, Cambridge, Massachusetts, assesses the effectiveness of the EPO program. In late 2009 through early 2010, more than 70 planetaria worldwide received the IBEX planetarium show. Of the many U.S. planetaria, the first 25 received the IBEX planetarium show and were offered the opportunity to receive, at no charge, accompanying informal education materials, including posters, lithographs, demonstration materials, lesson plans, and more. In Spring 2010, PERG staff conducted a study designed to gauge the effectiveness of the distribution process for the planetarium show, gather information on the professional development needs of the organizations, and document reactions of museum staff to the IBEX informal education materials and their usefulness as companion pieces to the planetarium show. In this paper, we will present preliminary findings of this particular study, in the hopes that future EPO work can make use of data in this report.
FWP executive summaries, Basic Energy Sciences Materials Sciences Programs (SNL/NM)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Samara, G.A.
1997-05-01
The BES Materials Sciences Program has the central theme of Scientifically Tailored Materials. The major objective of this program is to combine Sandia`s expertise and capabilities in the areas of solid state sciences, advanced atomic-level diagnostics and materials synthesis and processing science to produce new classes of tailored materials as well as to enhance the properties of existing materials for US energy applications and for critical defense needs. Current core research in this program includes the physics and chemistry of ceramics synthesis and processing, the use of energetic particles for the synthesis and study of materials, tailored surfaces and interfacesmore » for materials applications, chemical vapor deposition sciences, artificially-structured semiconductor materials science, advanced growth techniques for improved semiconductor structures, transport in unconventional solids, atomic-level science of interfacial adhesion, high-temperature superconductors, and the synthesis and processing of nano-size clusters for energy applications. In addition, the program includes the following three smaller efforts initiated in the past two years: (1) Wetting and Flow of Liquid Metals and Amorphous Ceramics at Solid Interfaces, (2) Field-Structured Anisotropic Composites, and (3) Composition-Modulated Semiconductor Structures for Photovoltaic and Optical Technologies. The latter is a joint effort with the National Renewable Energy Laboratory. Separate summaries are given of individual research areas.« less
Method of forming aluminum oxynitride material and bodies formed by such methods
Bakas, Michael P [Ammon, ID; Lillo, Thomas M [Idaho Falls, ID; Chu, Henry S [Idaho Falls, ID
2010-11-16
Methods of forming aluminum oxynitride (AlON) materials include sintering green bodies comprising aluminum orthophosphate or another sacrificial material therein. Such green bodies may comprise aluminum, oxygen, and nitrogen in addition to the aluminum orthophosphate. For example, the green bodies may include a mixture of aluminum oxide, aluminum nitride, and aluminum orthophosphate or another sacrificial material. Additional methods of forming aluminum oxynitride (AlON) materials include sintering a green body including a sacrificial material therein, using the sacrificial material to form pores in the green body during sintering, and infiltrating the pores formed in the green body with a liquid infiltrant during sintering. Bodies are formed using such methods.
Lateral Condyle Fracture of the Humerus in Children Treated with Bioabsorbable Materials
Tercier, Stéphane; Bregou-Bourgeois, Aline; Zambelli, Pierre-Yves
2013-01-01
The aim of this study was to compare clinical and radiological outcome of lateral condyle fracture of the elbow in children treated with bioabsorbable or metallic material. From January 2008 to December 2009, 16 children with similar fractures and ages were grouped according to the fixation material used. Children were seen at 3, 6, and 12 months and more than 4 years (mean 51.8 months) postoperatively. The clinical results were compared using the Mayo Elbow Performance Score (MEPS). Radiographic studies of the fractured and opposite elbow were assessed at last follow-up control. Twelve children had a sufficient followup and could be included in the study. Seven could be included in the traditional group and 5 in the bioabsorbable group. At 12 months, the MEPS was 100 for every child in both groups. Asymptomatic bony radiolucent visible tracks and heterotopic ossifications were noted in both groups. There were no significant differences in terms of clinical and radiological outcome between the two groups. The use of bioabsorbable pins or screws is a reasonable alternative to the traditional use of metallic materials for the treatment of lateral condyle fracture of the elbow in children. PMID:24228016
Advances in nonlinear optical materials and devices
NASA Technical Reports Server (NTRS)
Byer, Robert L.
1991-01-01
The recent progress in the application of nonlinear techniques to extend the frequency of laser sources has come from the joint progress in laser sources and in nonlinear materials. A brief summary of the progress in diode pumped solid state lasers is followed by an overview of progress in nonlinear frequency extension by harmonic generation and parametric processes. Improved nonlinear materials including bulk crystals, quasiphasematched interactions, guided wave devices, and quantum well intersubband studies are discussed with the idea of identifying areas of future progress in nonlinear materials and devices.
NASA Technical Reports Server (NTRS)
Selvaduray, Guna; Lomax, Curtis
1991-01-01
Fusible heat sinks are a possible source for thermal regulation of space suited astronauts. An extensive database search was undertaken to identify candidate materials with liquid solid transformations over the temperature range of -18 C to 5 C; and 1215 candidates were identified. Based on available data, 59 candidate materials with thermal storage capability, DeltaH values higher than that of water were identified. This paper presents the methodology utilized in the study, including the decision process used for materials selection.
NASA Technical Reports Server (NTRS)
Valentine, Peter G.; Lawrence, Timothy W.; Gubert, Michael K.; Milos, Frank S.; Kiser, James D.; Ohlhorst, Craig W.; Koenig, John R.
2006-01-01
As a collaborative effort among NASA Centers, the "Lightweight Nonmetallic Thermal Protection Materials Technology" Project was set up to assist mission/vehicle design trade studies, to support risk reduction in thermal protection system (TPS) material selections, to facilitate vehicle mass optimization, and to aid development of human-rated TPS qualification and certification plans. Missions performing aerocapture, aerobraking, or direct aeroentry rely on advanced heatshields that allow reductions in spacecraft mass by minimizing propellant requirements. Information will be presented on candidate materials for such reentry approaches and on screening tests conducted (material property and space environmental effects tests) to evaluate viable candidates. Seventeen materials, in three classes (ablatives, tiles, and ceramic matrix composites), were studied. In additional to physical, mechanical, and thermal property tests, high heat flux laser tests and simulated-reentry oxidation tests were performed. Space environmental effects testing, which included exposures to electrons, atomic oxygen, and hypervelocity impacts, was also conducted.
Micro-Fabricated Perforated Polymer Devices for Long-Term Drug Delivery
2011-02-24
conventional manufacturing methods. We have used a biocompatible polymer ( polyimide ) to serve as a reservoir and photolithographically produced microholes for...RIE with ICP source was used to etch holes on polyimide surface. Biocompatible materials Ti, SiO2 and SiNx were studied as mask materials. Ti film...used to fabricate micro holes on the surface of polyimide tubes. Several materials have been used to form the etching mask, including titanium film
Sail film materials and supporting structure for a solar sail, a preliminary design, volume 4
NASA Technical Reports Server (NTRS)
Rowe, W. M. (Editor)
1978-01-01
Solar sailing technology was examined in relation to a mission to rendezvous with Halley's Comet. Development of an ultra-light, highly reflecting material system capable of operating at high solar intensity for long periods of time was emphasized. Data resulting from the sail materials study are reported. Topics covered include: basic film; coatings and thermal control; joining and handling; system performance; and supporting structures assessment for the heliogyro.
X-Ray Micro-Tomography Applied to Nasa's Materials Research: Heat Shields, Parachutes and Asteroids
NASA Technical Reports Server (NTRS)
Panerai, Francesco; Borner, Arnaud; Ferguson, Joseph C.; Mansour, Nagi N.; Stern, Eric C.; Barnard, Harold S.; Macdowell, Alastair A.; Parkinson, Dilworth Y.
2017-01-01
X-ray micro-tomography is used to support the research on materials carried out at NASA Ames Research Center. The technique is applied to a variety of applications, including the ability to characterize heat shield materials for planetary entry, to study the Earth- impacting asteroids, and to improve broadcloths of spacecraft parachutes. From micro-tomography images, relevant morphological and transport properties are determined and validated against experimental data.
ERIC Educational Resources Information Center
Nordenstreng, Kaarle; Varis, Tapio
An international inventory was made to determine the composition of television programs, particularly from the point of view of program material exported to a country outside. A survey was also made of the international networks for sales and exchanges of program material for broadcast. A report of these studies includes the scope and methods of…
ERIC Educational Resources Information Center
Delaware Univ., Newark. Coll. of Education.
Included are four units related to coastal and oceanic awareness. The units are: (1) The Muskrat; (2) The Not-So-Common Oyster; (3) The Horseshoe Crab; and (4) The Blue Crab. All four units are designed for elementary school students. Each unit contains teacher background materials, student activity materials, evaluation materials, transparency…
Guha, Subhendu; Ovshinsky, Stanford R.
1988-10-04
An n-type microcrystalline semiconductor alloy material including a band gap widening element; a method of fabricating p-type microcrystalline semiconductor alloy material including a band gap widening element; and electronic and photovoltaic devices incorporating said n-type and p-type materials.
Ternary Blends of High Aluminate Cement, Fly ash and Blast-furnace slag for Sewerage Lining Mortar
NASA Astrophysics Data System (ADS)
Chao, L. C.; Kuo, C. P.
2018-01-01
High aluminate cement (HAC), fly ash (FA) and blast-furnace slag (BFS) have been treated sustainable materials for the use of cement products for wastewater infrastructure due to their capabilities of corrosion resistance. The purpose of this study is to optimize a ternary blend of above mentioned materials for a special type of mortar for sewerage lining. By the using of Taguchi method, four control parameters including water/cementitious material ratio, mix water content, fly ash content and blast-furnace slag content were considered in nine trial mix designs in this study. By evaluating target properties including (1) maximization of compressive strength, (2) maximization of electricity resistance and (3) minimization of water absorption rate, the best possible levels for each control parameter were determined and the optimal mix proportions were verified. Through the implementation of the study, a practical and completed idea for designing corrosion resistive mortar comprising HAC, FA and BSF is provided.
A parametric study of single-wall carbon nanotube growth by laser ablation
NASA Technical Reports Server (NTRS)
Arepalli, Sivaram; Holmes, William A.; Nikolaev, Pavel; Hadjiev, Victor G.; Scott, Carl D.
2004-01-01
Results of a parametric study of carbon nanotube production by the double-pulse laser oven process are presented. The effect of various operating parameters on the production of single-wall carbon nanotubes (SWCNTs) is estimated by characterizing the nanotube material using analytical techniques, including scanning electron microscopy, transmission electron microscopy, thermo gravimetric analysis and Raman spectroscopy. The study included changing the sequence of the laser pulses, laser energy, pulse separation, type of buffer gas used, operating pressure, flow rate, inner tube diameter, as well as its material, and oven temperature. It was found that the material quality and quantity improve with deviation from normal operation parameters such as laser energy density higher than 1.5 J/cm2, pressure lower than 67 kPa, and flow rates higher than 100 sccm. Use of helium produced mainly small diameter tubes and a lower yield. The diameter of SWCNTs decreases with decreasing oven temperature and lower flow rates.
Study on processing immiscible materials in zero gravity
NASA Technical Reports Server (NTRS)
Reger, J. L.; Mendelson, R. A.
1975-01-01
An experimental investigation was conducted to evaluate mixing immiscible metal combinations under several process conditions. Under one-gravity, these included thermal processing, thermal plus electromagnetic mixing, and thermal plus acoustic mixing. The same process methods were applied during free fall on the MSFC drop tower facility. The design is included of drop tower apparatus to provide the electromagnetic and acoustic mixing equipment, and a thermal model was prepared to design the specimen and cooling procedure. Materials systems studied were Ca-La, Cd-Ga and Al-Bi; evaluation of the processed samples included the morphology and electronic property measurements. The morphology was developed using optical and scanning electron microscopy and microprobe analyses. Electronic property characterization of the superconducting transition temperatures were made using an impedance change-tuned coil method.
WITHDRAWN: Dental fillings for the treatment of caries in the primary dentition.
Yengopal, Veerasamy; Harnekar, Soraya Yasin; Patel, Naren; Siegfried, Nandi
2016-10-17
Childhood caries (tooth decay) consists of a form of tooth decay that affects the milk teeth (also known as baby or primary teeth) of children. This may range from tooth decay in a single tooth to rampant caries affecting all the teeth in the mouth. Primary teeth in young children are vital to their development and every effort should be made to retain these teeth for as long as is possible. Dental fillings or restorations have been used as an intervention to repair these damaged teeth. Oral health professionals need to make astute decisions about the type of restorative (filling) material they choose to best manage their patients with childhood caries. This decision is by no means an easy one as remarkable advances in dental restorative materials over the last 10 years has seen the introduction of a multitude of different filling materials claiming to provide the best performance in terms of durability, aesthetics, symptom relief, etc when placed in the mouth. This review sought to compare the different types of dental materials against each other for the same outcomes. The objective of this review was to compare the outcomes (including pain relief, survival and aesthetics) for restorative materials used to treat caries in the primary dentition in children. Additionally, the restoration of teeth was compared with extraction and no treatment. Electronic searches of the following databases were undertaken: the Cochrane Oral Health Group's Trials Register (up to January 2009); CENTRAL (The Cochrane Library 2009, Issue1); MEDLINE (1966 to January 2009); EMBASE (1996 to January 2009); SIGLE (1976 to 2004); and conference proceedings on early childhood caries, restorative materials for paediatric dentistry, and material sciences conferences for dental materials used for children's dentistry (1990 to 2008). The searches attempted to identify all relevant studies irrespective of language.Additionally, the reference lists from articles of eligible papers were searched, handsearching of key journals was undertaken, and personal communication with authors and manufacturers of dental materials was initiated to increase the pool of suitable trials (both published and unpublished) for inclusion into this review. Randomised controlled trials (RCTs) or quasi-randomised controlled trials with a minimum period of 6 months follow up were included. Both parallel group and split-mouth study designs were considered. The unit of randomisation could be the individual, group (school, school class, etc), tooth or tooth pair. Included studies had a drop-out rate of less than 30%. The eligible trials consisted of young children (children less than 12 years) with tooth decay involving at least one tooth in the primary dentition which was symptomatic or symptom free at the start of the study. Data were independently extracted, in duplicate, by two review authors. Disagreements were resolved by consultation with a third review author. Authors were contacted for missing or unclear information regarding randomisation, allocation sequence, presentation of data, etc. A quality assessment of included trials was undertaken. The Cochrane Collaboration statistical guidelines were followed for data analysis. Only three studies were included in this review. The Fuks 1999 study assessed the clinical performance of aesthetic crowns versus conventional stainless steel crowns in 11 children who had at least two mandibular primary molars that required a crown restoration. The outcomes assessed at 6 months included gingival health (odds ratio (OR) 0.3; 95% confidence interval (CI) 0.01 to 8.32), restoration failure (OR 3.29; 95% CI 0.12 to 89.81), occlusion, proximal contact and marginal integrity. The odds ratios for occlusion, proximal contact and marginal integrity could not be estimated as no events were recorded at the 6-month evaluation. The Donly 1999 split-mouth study compared a resin-modified glass ionomer (Vitremer) with amalgam over a 36-month period. Forty pairs of Class II restorations were placed in 40 patients (21 males; 19 females; mean age 8 years +/- 1.17; age range 6 to 9 years). Although the study period was 3 years (36 months), only the 6- and 12-month results are reported due to the loss to follow up of patients being greater than 30% for the 24- and 36-month data. Marks 1999a recruited 30 patients (age range 4 to 9 years; mean age 6.7 years, standard deviation 2.3) with one pair of primary molars that required a Class II restoration. The materials tested were Dyract (compomer) and Tytin (amalgam). Loss to follow up at 24 and 36 months was 20% and 43% respectively. This meant that only the 24-month data were useable. For all of the outcomes compared in all three studies, there were no significant differences in clinical performance between the materials tested.No studies were found that compared restorations versus extractions or no treatment as an intervention in children with childhood caries. It was disappointing that only three trials that compared three different types of materials were suitable for inclusion into this review. There were no significant differences found in all three trials for all of the outcomes assessed. Well designed, randomised controlled trials comparing the different types of filling materials for similar outcomes are urgently needed in dentistry. There was insufficient evidence from the three included trials to make any recommendations about which filling material to use.
Magnetic Materials Suitable for Fission Power Conversion in Space Missions
NASA Technical Reports Server (NTRS)
Bowman, Cheryl L.
2012-01-01
Terrestrial fission reactors use combinations of shielding and distance to protect power conversion components from elevated temperature and radiation. Space mission systems are necessarily compact and must minimize shielding and distance to enhance system level efficiencies. Technology development efforts to support fission power generation scenarios for future space missions include studying the radiation tolerance of component materials. The fundamental principles of material magnetism are reviewed and used to interpret existing material radiation effects data for expected fission power conversion components for target space missions. Suitable materials for the Fission Power System (FPS) Project are available and guidelines are presented for bounding the elevated temperature/radiation tolerance envelope for candidate magnetic materials.
Effectiveness of the training material in drug-dose calculation skills.
Basak, Tulay; Aslan, Ozlem; Unver, Vesile; Yildiz, Dilek
2016-07-01
The aim of study was to evaluate the effectiveness of the training material based on low-level environmental fidelity simulation in drug-dose calculation skills in senior nursing students. A quasi-experimental design with one group. The sample included senior nursing students attending a nursing school in Turkey in the period December 2012-January 2013. Eighty-two senior nursing students were included in the sample. Data were obtained using a data collection form which was developed by the researchers. A paired-sample t-test was used to compare the pretest and post-test scores. The difference between the mean pretest score and the mean post-test score was statistically significant (P < 0.05). This study revealed that the training material based on low-level environmental fidelity simulation positively impacted accurate drug-dose calculation skills in senior nursing students. © 2016 Japan Academy of Nursing Science.
Carbon nanotubes in neural interfacing applications
NASA Astrophysics Data System (ADS)
Voge, Christopher M.; Stegemann, Jan P.
2011-02-01
Carbon nanotubes (CNT) are remarkable materials with a simple and inert molecular structure that gives rise to a range of potentially valuable physical and electronic properties, including high aspect ratio, high mechanical strength and excellent electrical conductivity. This review summarizes recent research on the application of CNT-based materials to study and control cells of the nervous system. It includes the use of CNT as cell culture substrates, to create patterned surfaces and to study cell-matrix interactions. It also summarizes recent investigations of CNT toxicity, particularly as related to neural cells. The application of CNT-based materials to directing the differentiation of progenitor and stem cells toward neural lineages is also discussed. The emphasis is on how CNT surface chemistry and nanotopography can be altered, and how such changes can affect neural cell function. This knowledge can be applied to creating improved neural interfaces and devices, as well as providing new approaches to neural tissue engineering and regeneration.
How is that done? Student views on resources used outside the engineering classroom
NASA Astrophysics Data System (ADS)
Maclaren, Peter
2018-07-01
While the traditional lecture remains a key feature in the teaching of mathematically intensive disciplines at a tertiary level, what students do outside class, the resources they use, and how they use them are critical factors in their success. This study reports on a survey of students studying a range of engineering subjects, giving their views on the effectiveness of resources that they use outside the classroom. Resource types examined included textbooks, lecturer course notes, in-class developed notes, and other online material, including multimedia. While lecturer-generated material was generally seen as more effective than formal textbooks and social media, external screencasts were rated as most effective where material appropriate to their class was available. It is suggested that student use of screencast resources has the potential to facilitate improved learning outcomes, and with accompanying changes in assessment focus, may enable more substantive pedagogical changes.
ERIC Educational Resources Information Center
De Baz, Theodora; El-Weher, Mahmoud
2012-01-01
The purpose of this study was to detect the extent to which contextual material of a unit on "The origin and evolution of living organisms" included in the high-school biology curriculum in Jordan affected students' acceptance of the theory of evolution. The participants of this study consisted of 107 tenth-grade students randomly drawn…
ERIC Educational Resources Information Center
Chubbuck, Kay; Curley, W. Edward; King, Teresa C.
2016-01-01
This study gathered quantitative and qualitative evidence concerning gender differences in performance by using critical reading material on the "SAT"® test with sports and science content. The fundamental research questions guiding the study were: If sports and science are to be included in a skills test, what kinds of material are…
ERIC Educational Resources Information Center
DuVall, Charles R.; And Others
The focus of this study was teacher assessment of several factors relating to selected materials provided by the American Iron and Steel Institute. The design and rationale, instrumentation, methodology, and questionnaire mailing are discussed in Chapter I. Chapter II reviews the related literature, including the historic nature of free and…
Organic light emitting device architecture for reducing the number of organic materials
D'Andrade, Brian [Westampton, NJ; Esler, James [Levittown, PA
2011-10-18
An organic light emitting device is provided. The device includes an anode and a cathode. A first emissive layer is disposed between the anode and the cathode. The first emissive layer includes a first non-emitting organic material, which is an organometallic material present in the first emissive layer in a concentration of at least 50 wt %. The first emissive layer also includes a first emitting organic material. A second emissive layer is disposed between the first emissive layer and the cathode, preferably, in direct contact with the first emissive layer. The second emissive material includes a second non-emitting organic material and a second emitting organic material. The first and second non-emitting materials, and the first and second emitting materials, are all different materials. A first non-emissive layer is disposed between the first emissive layer and the anode, and in direct contact with the first emissive layer. The first non- emissive layer comprises the first non-emissive organic material.
NASA Technical Reports Server (NTRS)
Trinh, E. H.
1985-01-01
An ultrasonic levitation device operable in both ordinary ground-based as well as in potential space-borne laboratories is described together with its various applications in the fields of fluid dynamics, material science, and light scattering. Some of the phenomena which can be studied by this instrument include surface waves on freely suspended liquids, the variations of the surface tension with temperature and contamination, the deep undercooling of materials with the temperature variations of their density and viscosity, and finally some of the optical diffraction properties of transparent substances.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cluff, D.
1996-04-01
The Center operates under a cooperative agreement between DOE and the State of Texas and is directed and administered by an education consortium. Its programs include developing peaceful uses for the materials removed from dismantled weapons, studying effects of nuclear materials on environment and public health, remedying contaminated soils and water, studying storage, disposition, and transport of Pu, HE, and other hazardous materials removed from weapons, providing research and counsel to US in carrying out weapons reductions in cooperation with Russia, and conducting a variety of education and training programs.
Photonic crystals, amorphous materials, and quasicrystals
Edagawa, Keiichi
2014-01-01
Photonic crystals consist of artificial periodic structures of dielectrics, which have attracted much attention because of their wide range of potential applications in the field of optics. We may also fabricate artificial amorphous or quasicrystalline structures of dielectrics, i.e. photonic amorphous materials or photonic quasicrystals. So far, both theoretical and experimental studies have been conducted to reveal the characteristic features of their optical properties, as compared with those of conventional photonic crystals. In this article, we review these studies and discuss various aspects of photonic amorphous materials and photonic quasicrystals, including photonic band gap formation, light propagation properties, and characteristic photonic states. PMID:27877676
Photonic crystals, amorphous materials, and quasicrystals.
Edagawa, Keiichi
2014-06-01
Photonic crystals consist of artificial periodic structures of dielectrics, which have attracted much attention because of their wide range of potential applications in the field of optics. We may also fabricate artificial amorphous or quasicrystalline structures of dielectrics, i.e. photonic amorphous materials or photonic quasicrystals. So far, both theoretical and experimental studies have been conducted to reveal the characteristic features of their optical properties, as compared with those of conventional photonic crystals. In this article, we review these studies and discuss various aspects of photonic amorphous materials and photonic quasicrystals, including photonic band gap formation, light propagation properties, and characteristic photonic states.
Development of educational image databases and e-books for medical physics training.
Tabakov, S; Roberts, V C; Jonsson, B-A; Ljungberg, M; Lewis, C A; Wirestam, R; Strand, S-E; Lamm, I-L; Milano, F; Simmons, A; Deane, C; Goss, D; Aitken, V; Noel, A; Giraud, J-Y; Sherriff, S; Smith, P; Clarke, G; Almqvist, M; Jansson, T
2005-09-01
Medical physics education and training requires the use of extensive imaging material and specific explanations. These requirements provide an excellent background for application of e-Learning. The EU projects Consortia EMERALD and EMIT developed five volumes of such materials, now used in 65 countries. EMERALD developed e-Learning materials in three areas of medical physics (X-ray diagnostic radiology, nuclear medicine and radiotherapy). EMIT developed e-Learning materials in two further areas: ultrasound and magnetic resonance imaging. This paper describes the development of these e-Learning materials (consisting of e-books and educational image databases). The e-books include tasks helping studying of various equipment and methods. The text of these PDF e-books is hyperlinked with respective images. The e-books are used through the readers' own Internet browser. Each Image Database (IDB) includes a browser, which displays hundreds of images of equipment, block diagrams and graphs, image quality examples, artefacts, etc. Both the e-books and IDB are engraved on five separate CD-ROMs. Demo of these materials can be taken from www.emerald2.net.
Ground-Based Research within NASA's Materials Science Program
NASA Technical Reports Server (NTRS)
Gillies, Donald C.; Curreri, Peter (Technical Monitor)
2002-01-01
Ground-based research in Materials Science for NASA's Microgravity program serves several purposes, and includes approximately four Principal Investigators for every one in the flight program. While exact classification is difficult. the ground program falls roughly into the following categories: (1) Intellectual Underpinning of the Flight Program - Theoretical Studies; (2) Intellectual Underpinning of the Flight Program - Bringing to Maturity New Research; (3) Intellectual Underpinning of the Flight Program - Enabling Characterization; (4) Intellectual Underpinning of the Flight Program - Thermophysical Property Determination; (5) Radiation Shielding; (6) Preliminary In Situ Resource Utilization; (7) Biomaterials; (8) Nanostructured Materials; (9) Materials Science for Advanced Space Propulsion. It must be noted that while the first four categories are aimed at using long duration low gravity conditions, the other categories pertain more to more recent NASA initiatives in materials science. These new initiatives address NASA's future materials science needs in the realms of crew health and safety, and exploration, and have been included in the most recent NASA Research Announcements (NRA). A description of each of these nine categories will be given together with examples of the kinds of research being undertaken.
Engineering Properties and Correlation Analysis of Fiber Cementitious Materials
Lin, Wei-Ting; Wu, Yuan-Chieh; Cheng, An; Chao, Sao-Jeng; Hsu, Hui-Mi
2014-01-01
This study focuses on the effect of the amount of silica fume addition and volume fraction of steel fiber on the engineering properties of cementitious materials. Test variables include dosage of silica fume (5% and 10%), water/cement ratio (0.35 and 0.55) and steel fiber dosage (0.5%, 1.0% and 2.0%). The experimental results included: compressive strength, direct tensile strength, splitting tensile strength, surface abrasion and drop-weight test, which were collected to carry out the analysis of variance to realize the relevancy and significance between material parameters and those mechanical properties. Test results illustrate that the splitting tensile strength, direct tensile strength, strain capacity and ability of crack-arresting increase with increasing steel fiber and silica fume dosages, as well as the optimum mixture of the fiber cementitious materials is 5% replacement silica fume and 2% fiber dosage. In addition, the Pearson correlation coefficient was conducted to evaluate the influence of the material variables and corresponds to the experiment result. PMID:28788256
Nondestructive spectroscopic characterization of building materials
NASA Astrophysics Data System (ADS)
Kassu, Aschalew; Walker, Lauren; Sanders, Rachel; Farley, Carlton; Mills, Jonathan; Sharma, Anup
2017-04-01
The purpose of this research project is to demonstrate the application of Raman spectroscopy technique for characterization and identification of the distinct Raman signatures of construction materials. The results reported include the spectroscopic characterization of building materials using compact Raman system with 785 nm wavelength laser. The construction materials studied include polyblend sanded grout, fire barrier sealant, acrylic latex caulk plus and white silicone. It is found that, both fire barrier sealant and acrylic latex caulk plus has a prominent Raman band at 1082 cm-1, and three minor Raman signatures located at 275, 706 and 1436 cm-1. On the other hand, sand grout has three major Raman bands at 1265, 1368 and 1455 cm-1, and four minor peaks at 1573, 1683, 1762, and 1868 cm-1. White silicone, which is a widely used sealant material in construction industry, has two major Raman bands at 482 and 703 cm-1, and minor Raman characteristic bands at 783 and 1409 cm-1.
Microimaging of transient guest profiles to monitor mass transfer in nanoporous materials
NASA Astrophysics Data System (ADS)
Kärger, Jörg; Binder, Tomas; Chmelik, Christian; Hibbe, Florian; Krautscheid, Harald; Krishna, Rajamani; Weitkamp, Jens
2014-04-01
The intense interactions of guest molecules with the pore walls of nanoporous materials is the subject of continued fundamental research. Stimulated by their thermal energy, the guest molecules in these materials are subject to a continuous, irregular motion, referred to as diffusion. Diffusion, which is omnipresent in nature, influences the efficacy of nanoporous materials in reaction and separation processes. The recently introduced techniques of microimaging by interference and infrared microscopy provide us with a wealth of information on diffusion, hitherto inaccessible from commonly used techniques. Examples include the determination of surface barriers and the sticking coefficient's analogue, namely the probability that, on colliding with the particle surface, a molecule may continue its diffusion path into the interior. Microimaging is further seen to open new vistas in multicomponent guest diffusion (including the detection of a reversal in the preferred diffusion pathways), in guest-induced phase transitions in nanoporous materials and in matching the results of diffusion studies under equilibrium and non-equilibrium conditions.
Current Concepts and Future Directions of CELSS
NASA Technical Reports Server (NTRS)
Macelroy, R. D.; Bredt, J.
1985-01-01
Bioregenerative life support systems for use in space were studied. Concepts of such systems include the use of higher plants and/or microalgae as sources of food, potable water and oxygen, and as sinks for carbon dioxide and metabolic wastes. Recycling of materials within the system will require processing of food organism and crew wastes using microbiological and/or physical chemical techniques. The dynamics of material flow within the system will require monitoring, control, stabilization and maintenance imposed by computers. Studies included higher plant and algal physiology, environmental responses, and control; flight experiments for testing responses of organisms to weightlessness and increased radiation levels; and development of ground based facilities for the study of recycling within a bioregenerative life support system.
Schütte, Stefanie; Chastang, Jean-François; Parent-Thirion, Agnès; Vermeylen, Greet; Niedhammer, Isabelle
2014-06-01
The aim of this study was to explore the associations between socio-demographic, psychosocial, material and occupational factors and self-reported health (SRH) in the European working population. Another objective was to examine whether these associations varied according to occupation and country. This study was based on data from the European quality of life survey 2007 including 17,005 workers from 31 European countries. SRH was measured using a single item. Factors were classified into four different groups: socio-demographic, psychosocial, material and occupational factors. The associations between these factors and SRH were examined using multilevel logistic regression analyses including interaction tests. When all four groups of factors were studied together, age, occupation, urbanization level, origin, trust level, social exclusion, material deprivation, financial and neighbourhood problems, access to medical services, quality of public services, psychological job demands, job reward, work-life imbalance and dangerous/unhealthy working conditions were associated with poor SRH. Almost no differences were found in these associations according to occupation and country. Various factors were associated with poor SRH. This study gave a first European overview of the associations between socio-demographic, psychosocial, material and occupational factors and SRH in Europe and could provide better advice to policy-makers at a European level. © The Author 2013. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Military Curriculum Materials for Vocational and Technical Education. Drainage, 3-5.
ERIC Educational Resources Information Center
Ohio State Univ., Columbus. National Center for Research in Vocational Education.
This individualized, self-paced course for independent study in water drainage was adapted from military curriculum materials for use in vocational education. The course provides basic information for the design of simple drainage structures for roads and airfields. Some job skills included are designing and constructing ditches and culverts;…
The Effects of Digital Learning Material on Students' Mathematics Learning in Vocational Education
ERIC Educational Resources Information Center
Zwart, Diana P.; Van Luit, Johannes E. H.; Noroozi, Omid; Goei, Sui Lin
2017-01-01
This study investigates the effects of Digital Learning Material (DLM) including instructional clips, online guidance, structuring of content, and a collaboration tool on students' mathematics learning in Dutch vocational education. A pretest-posttest design was used. Apprenticeship students were asked to complete assignments and to discuss them…
Environmental Microbiology Modules. Final Report.
ERIC Educational Resources Information Center
Walke, Raymond H.; Walke, Jayne G.
This publication is the result of a project to develop microbiology instructional materials for vocational college students. These materials are a series of self-paced modules. Each module includes a pre-test, an introduction and historical packet, an organizational packet to set the framework for in-depth study, one or more in-depth packets, a…
ERIC Educational Resources Information Center
Evans, Barbara; Honour, Leslie
1997-01-01
Reports on a study that required student teachers training in business education to produce open learning materials on intercultural communication. Analysis of stages and responses to this assignment revealed a distinction between "deep" and "surface" learning. Includes charts delineating the characteristics of these two types…
A Catalog of Curriculum Materials for Marine Environment Studies--Elementary and Secondary.
ERIC Educational Resources Information Center
Delaware Univ., Newark. Coll. of Marine Studies.
This partially annotated bibliography on marine environment contains a list of learning experiences and curriculum units for elementary and secondary students. A majority of materials were published in the 1970s. Subjects include biological oceanography, which deals with general and specific aspects of marine biology such as plankton,…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ellingson, W.A.
This broad-base materials engineering program, begun in October 1974, includes studies on both ceramic (refractory) and metallic materials presently being used or intended for use in coal-conversion systems. Appropriate laboratory and field experiments are integrated such that the results have immediate impact on the present pilot-plant and proposed demonstration-plant designs. The report presents the technical accomplishments.
Teaching Shakespeare: Materials and Outcomes for Web-Based Instruction and Class Adjunct.
ERIC Educational Resources Information Center
Schwartz, Helen J.
Multimedia hypertext materials have instructional advantages when used as adjuncts in traditional classes and as the primary means of instruction, as illustrated in this case study of college-level Shakespeare classes. Plays become more accessible through use of audio and video resources, including video clips from play productions. Student work…
ERIC Educational Resources Information Center
Ohio State Univ., Columbus. National Center for Research in Vocational Education.
This individualized, self-paced course for independent study in engine principles has been adapted from military curriculum materials for vocational education use. The course provides the student with basic information on engine principles including different kinds of combustion engines, lubrication systems, and cooling systems. It is organized…
Audiovisual Records in the National Archives Relating to Black History. Preliminary Draft.
ERIC Educational Resources Information Center
Waffen, Leslie; And Others
A representative selection of the National Archives and Records Services' audiovisual collection relating to black history is presented. The intention is not to provide an exhaustive survey, but rather to indicate the breadth and scope of materials available for study and to suggest areas for concentrated research. The materials include sound…
Industrial Arts 7-9. Manufacturing: Metalwork, Plastics, Woodwork, Manufacturing.
ERIC Educational Resources Information Center
Manitoba Dept. of Education, Winnipeg. Div. of Vocational Education.
This curriculum guide provides materials for the industrial arts (grades 7-9) subject cluster of manufacturing. This subject cluster has four areas of study: metalwork, plastics, woodwork, and manufacturing. Introductory materials include an overview of the industrial arts curriculum in its entirety, a listing of program objectives for each of the…
The Afro-American Family: Historical Strengths for the New Century.
ERIC Educational Resources Information Center
Association for the Study of Afro-American Life and History, Inc.
Instructional materials on the role of the black family in American history are collected in this study kit. Consisting of eleven separate informational pamphlets and an assortment of photographs and information sheets, the kit also includes advice on employing these materials in the elementary and secondary school classroom and with adults. Three…
NASA Technical Reports Server (NTRS)
1977-01-01
A coordinated Federal Government action plan for dealing with the potential problems arising from the increasing use of graphite fiber reinforced composite materials in both military and civilian applications is presented. The required dissemination of declassified information and an outline of government actions to minimize the social and economic consequences of proliferated composite materials applications were included.
The Use and Effects of Embedded Support Devices in Independent Learning.
ERIC Educational Resources Information Center
Martens, Rob
This book examines embedded support in course material. The focus is on self-study and associated concepts such as independent learning, distance education, and open education, and the general context is adult and higher education. The seven chapters cover: (1) general introductory material, including a description of the future, distance…
Educators' Guide to Great Lakes Materials: Books, Films, Maps and Pamphlets for Classroom Use.
ERIC Educational Resources Information Center
Johnson, Pam
This annotated bibliography presents Great Lakes information for grades six through nine classroom use. It is meant to facilitate and encourage Great Lakes study, particularly of Lakes Michigan and Superior. Material is presented on history, science, lake management, environmental concerns, and recreational use. Included are both fiction and…
Plumbing Specialist I, 3-21. Military Curriculum Materials for Vocational and Technical Education.
ERIC Educational Resources Information Center
Ohio State Univ., Columbus. National Center for Research in Vocational Education.
These military-developed curriculum materials consist of a course description, course chart, plan of instruction, and lesson plans for use in training a plumbing specialist I. Study guides and workbooks for student use are also included. This course on Introduction to Plumbing covers plumbing safety; plumbing systems, terminology, and engineering…
Surface electrical properties experiment study phase, volume 3
NASA Technical Reports Server (NTRS)
1973-01-01
The reliability and quality assurance system and procedures used in developing test equipment for the Lunar Experiment projects are described. The subjects discussed include the following: (1) documentation control, (2) design review, (3) parts and materials selection, (4) material procurement, (5) inspection procedures, (6) qualification and special testing, and failure modes and effects analysis.
Falinski, Mark M; Plata, Desiree L; Chopra, Shauhrat S; Theis, Thomas L; Gilbertson, Leanne M; Zimmerman, Julie B
2018-04-30
Engineered nanomaterials (ENMs) and ENM-enabled products have emerged as potentially high-performance replacements to conventional materials and chemicals. As such, there is an urgent need to incorporate environmental and human health objectives into ENM selection and design processes. Here, an adapted framework based on the Ashby material selection strategy is presented as an enhanced selection and design process, which includes functional performance as well as environmental and human health considerations. The utility of this framework is demonstrated through two case studies, the design and selection of antimicrobial substances and conductive polymers, including ENMs, ENM-enabled products and their alternatives. Further, these case studies consider both the comparative efficacy and impacts at two scales: (i) a broad scale, where chemical/material classes are readily compared for primary decision-making, and (ii) within a chemical/material class, where physicochemical properties are manipulated to tailor the desired performance and environmental impact profile. Development and implementation of this framework can inform decision-making for the implementation of ENMs to facilitate promising applications and prevent unintended consequences.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zahari, Suhaila Mohd; Norizan, Mohd Natashah; Mohamad, Ili Salwani
2015-05-15
The work presented in this paper is about the development of single and multilayer solar cells using GaAs and InGaAs in AM1.5 condition. The study includes the modeling structure and simulation of the device using Silvaco applications. The performance in term of efficiency of Indium Gallium Arsenide (InGaAs) and GaAs material was studied by modification of the doping concentration and thickness of material in solar cells. The efficiency of the GaAs solar cell was higher than InGaAs solar cell for single layer solar cell. Single layer GaAs achieved an efficiency about 25% compared to InGaAs which is only 2.65% ofmore » efficiency. For multilayer which includes both GaAs and InGaAs, the output power, P{sub max} was 8.91nW/cm² with the efficiency only 8.51%. GaAs is one of the best materials to be used in solar cell as a based compared to InGaAs.« less
NASA Technical Reports Server (NTRS)
Kerr, James R.; Haskins, James F.
1987-01-01
Advanced composites will play a key role in the development of the technology for the design and fabrication of future supersonic vehicles. However, incorporating the material into vehicle usage is contingent on accelerating the demonstration of service capacity and design technology. Because of the added material complexity and lack of extensive data, laboratory replication of the flight service will provide the most rapid method to document the airworthiness of advanced composite systems. Consequently, a laboratory program was conducted to determine the time-temperature-stress capabilities of several high temperature composites. Tests included were thermal aging, environmental aging, fatigue, creep, fracture, tensile, and real-time flight simulation exposure. The program had two phases. The first included all the material property determinations and aging and simulation exposures up through 10,000 hours. The second continued these tests up to 50,000 cumulative hours. This report presents the results of the Phase 1 baseline and 10,000-hr aging and flight simulation studies, the Phase 2 50,000-hr aging studies, and the Phase 2 flight simulation tests, some of which extended to almost 40,000 hours.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liby, Alan L; Rogers, Hiram
The goal of this activity was to carry out program implementation and technical projects in support of the ARRA-funded Advanced Materials in Support of EERE Needs to Advance Clean Energy Technologies Program of the DOE Advanced Manufacturing Office (AMO) (formerly the Industrial Technologies Program (ITP)). The work was organized into eight projects in four materials areas: strategic materials, structural materials, energy storage and production materials, and advanced/field/transient processing. Strategic materials included work on titanium, magnesium and carbon fiber. Structural materials included work on alumina forming austentic (AFA) and CF8C-Plus steels. The advanced batteries and production materials projects included work onmore » advanced batteries and photovoltaic devices. Advanced/field/transient processing included work on magnetic field processing. Details of the work in the eight projects are available in the project final reports which have been previously submitted.« less
NASA Technical Reports Server (NTRS)
Misra, Ajay K.
1988-01-01
Chemical compatibility of several reinforcement materials with beta phase NiAl alloys within the concentration range 40 to 50 at. percent Al have been analyzed from thermodynamic considerations at 1373 and 1573 K. The reinforcement materials considered in this study include carbides, borides, oxides, nitrides, beryllides, and silicides. Thermodynamic data for NiAl alloys have been reviewed and activity of Ni and Al in the beta phase have been derived at 1373 and 1573 K. Criteria for chemical compatibility between the reinforcement material and the matrix have been defined and several chemically compatible reinforcement materials have been defined.
A training tool for visual aids. Using tracing techniques to create visual aids.
Clark, M; Walters, J E; Wileman, R
1982-01-01
This training tool explains the use of tracing techniques to create visuals requiring few materials and no training of special skills in drawing. Magazines, books, posters, and many other materials contain photographs and drawings which can be used to create visual aids for health training and public health education. The materials required are pencils, an eraser, crayons or colored marking pens, paper clips, tracing and drawing paper, carbon paper, and sources of visual images. The procedure is described. The material was prepared by INTRAH staff members. Other materials include how to evaluate teaching, how to create a family health case study and training in group dynamics.
Program for the development of high temperature electrical materials and components
NASA Technical Reports Server (NTRS)
Neff, W. S.; Lowry, L. R.
1972-01-01
Evaluation of high temperature, space-vacuum performance of selected electrical materials and components, high temperature capacitor development, and evaluation, construction, and endurance testing of compression sealed pyrolytic boron nitride slot insulation are described. The first subject above covered the aging evaluation of electrical devices constructed from selected electrical materials. Individual materials performances were also evaluated and reported. The second subject included study of methods of improving electrical performance of pyrolytic boron nitride capacitors. The third portion was conducted to evaluate the thermal and electrical performance of pyrolytic boron nitride as stator slot liner material under varied temperature and compressive loading. Conclusions and recommendations are presented.
Review of research and developments in self healing composite materials
NASA Astrophysics Data System (ADS)
Reddy Madara, Sahith; Sarath Raj, N. S.; Pon Selvan, Chithirai, Dr.
2018-04-01
Self-healing materials are artificial or synthetically created substances that have the built-in ability to automatically repair damage to themselves without any external diagnosis of the problem or human intervention. This article presents the current research and developments in self-healing composite materials. A detailed study is conducted on various types of self-healing composites with their self-healing mechanisms. The applications of self-healing materials in various fields including space sector is also discussed. Economics and Future outlooks for self-healing smart materials is highlighted at the end of the article. This research article will be useful to manufacturers, policy makers and researchers widely.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Hua Kun, E-mail: hua@uow.edu.au
2013-12-15
Graphical abstract: Nanomaterials play important role in lithium ion batteries, supercapacitors, hydrogen storage and fuel cells. - Highlights: • Nanomaterials play important role for lithium rechargeable batteries. • Nanostructured materials increase the capacitance of supercapacitors. • Nanostructure improves the hydrogenation/dehydrogenation of hydrogen storage materials. • Nanomaterials enhance the electrocatalytic activity of the catalysts in fuel cells. - Abstract: There is tremendous worldwide interest in functional nanostructured materials, which are the advanced nanotechnology materials with internal or external dimensions on the order of nanometers. Their extremely small dimensions make these materials unique and promising for clean energy applications such as lithiummore » ion batteries, supercapacitors, hydrogen storage, fuel cells, and other applications. This paper will highlight the development of new approaches to study the relationships between the structure and the physical, chemical, and electrochemical properties of functional nanostructured materials. The Energy Materials Research Programme at the Institute for Superconducting and Electronic Materials, the University of Wollongong, has been focused on the synthesis, characterization, and applications of functional nanomaterials, including nanoparticles, nanotubes, nanowires, nanoporous materials, and nanocomposites. The emphases are placed on advanced nanotechnology, design, and control of the composition, morphology, nanostructure, and functionality of the nanomaterials, and on the subsequent applications of these materials to areas including lithium ion batteries, supercapacitors, hydrogen storage, and fuel cells.« less
Effects of Radiation on Capacitor Dielectrics
NASA Technical Reports Server (NTRS)
Bouquet, F. L.; Somoano, R. B.; Frickland, P. O.
1987-01-01
Data gathered on key design parameters. Report discusses study of electrical and mechanical properties of irradiated polymer dielectric materials. Data compiled for use by designers of high-energy-density capacitors that operate in presence of ionizing radiation. Study focused on polycarbonates, polyetheretherketones, polymethylpentenes, polyimides (including polyetherimide), polyolefins, polysulfones (including polyethersulfone and polyphenylsulfone), and polyvinylidene fluorides.
Infrared tag and track technique
Partin, Judy K.; Stone, Mark L.; Slater, John; Davidson, James R.
2007-12-04
A method of covertly tagging an object for later tracking includes providing a material capable of at least one of being applied to the object and being included in the object, which material includes deuterium; and performing at least one of applying the material to the object and including the material in the object in a manner in which in the appearance of the object is not changed, to the naked eye.
Characterization of dielectric materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
King, Danny J.; Babinec, Susan; Hagans, Patrick L.
2017-06-27
A system and a method for characterizing a dielectric material are provided. The system and method generally include applying an excitation signal to electrodes on opposing sides of the dielectric material to evaluate a property of the dielectric material. The method can further include measuring the capacitive impedance across the dielectric material, and determining a variation in the capacitive impedance with respect to either or both of a time domain and a frequency domain. The measured property can include pore size and surface imperfections. The method can still further include modifying a processing parameter as the dielectric material is formedmore » in response to the detected variations in the capacitive impedance, which can correspond to a non-uniformity in the dielectric material.« less
Non-thermal plasma conversion of hydrocarbons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Strohm, James J.; Skoptsov, George L.; Musselman, Evan T.
A non-thermal plasma is generated to selectively convert a precursor to a product. More specifically, plasma forming material and a precursor material are provided to a reaction zone of a vessel. The reaction zone is exposed to microwave radiation, including exposing the plasma forming material and the precursor material to the microwave radiation. The exposure of the plasma forming material to the microwave radiation selectively converts the plasma forming material to a non-thermal plasma including formation of one or more streamers. The precursor material is mixed with the plasma forming material and the precursor material is exposed to the non-thermalmore » plasma including exposing the precursor material to the one or more streamers. The exposure of the precursor material to the streamers and the microwave radiation selectively converts the precursor material to a product.« less
Buffer layers for coated conductors
Stan, Liliana [Los Alamos, NM; Jia, Quanxi [Los Alamos, NM; Foltyn, Stephen R [Los Alamos, NM
2011-08-23
A composite structure is provided including a base substrate, an IBAD oriented material upon the base substrate, and a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material. Additionally, an article is provided including a base substrate, an IBAD oriented material upon the base substrate, a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material, and a thick film upon the cubic metal oxide material. Finally, a superconducting article is provided including a base substrate, an IBAD oriented material upon the base substrate, a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material, and an yttrium barium copper oxide material upon the cubic metal oxide material.
Composite materials for battery applications
Amine, Khalil; Yang, Junbing; Abouimrane, Ali; Ren, Jianguo
2017-03-14
A process for producing nanocomposite materials for use in batteries includes electroactive materials are incorporated within a nanosheet host material. The process may include treatment at high temperatures and doping to obtain desirable properties.
ERIC Educational Resources Information Center
McCoy, Leah P., Ed.
2005-01-01
These Proceedings document an educational research forum held at Wake Forest University (Winston-Salem, North Carolina) on December 8, 2004. Table of contents and 26 research studies of high school teaching are included. Studies include: The Use of Authentic Materials in the K-12 French Program (Katherine Elizabeth Baird), Surveying Students: What…
ERIC Educational Resources Information Center
Friedstein, Harriet, Ed.
1981-01-01
Lists commercially available audiovisual materials by subject area. Includes title, producer (addresses given), catalog number, format (film, filmstrip, cassette, slides), and prices. Subject areas include: elements; equilibrium; gases; laboratory techniques and experiments; general chemistry; introductory materials (including mathematics); and…
HIDRA-MAT: A Material Analysis Tool for Fusion Devices
NASA Astrophysics Data System (ADS)
Andruczyk, Daniel; Rizkallah, Rabel; Bedoya, Felipe; Kapat, Aveek; Schamis, Hanna; Allain, Jean Paul
2017-10-01
The former WEGA stellarator which is now operating as HIDRA at the University of Illinois will be almost exclusively used to study the intimate relationship between the plasma interacting with surfaces of different materials. A Material Analysis Tool (HIDRA-MAT) is being designed and will be built based on the successful Material Analysis and Particle Probe (MAPP) which is currently used on NSTX-U at PPPL. This will be an in-situ material diagnostic probe, meaning that all analysis can be done without breaking vacuum. This allows surface changes to be studied in real-time. HIDRA-MAT will consist of several in-situ diagnostics including Langmuir probes (LP), Thermal Desorption Spectroscopy (TDS), X-ray Photo Spectroscopy (XPS) and Ion Scattering Spectroscopy (ISS). This presentation will outline the HIDRA-MAT diagnostic and initial design, as well as its integration into the HIDRA system.
Frontiers of in situ electron microscopy
Zheng, Haimei; Zhu, Yimei; Meng, Shirley Ying
2015-01-01
In situ transmission electron microscopy (TEM) has become an increasingly important tool for materials characterization. It provides key information on the structural dynamics of a material during transformations and the correlation between structure and properties of materials. With the recent advances in instrumentation, including aberration corrected optics, sample environment control, the sample stage, and fast and sensitive data acquisition, in situ TEM characterization has become more and more powerful. In this article, a brief review of the current status and future opportunities of in situ TEM is included. It also provides an introduction to the six articles covered by inmore » this issue of MRS Bulletin explore the frontiers of in situ electron microscopy, including liquid and gas environmental TEM, dynamic four-dimensional TEM, nanomechanics, ferroelectric domain switching studied by in situ TEM, and state-of-the-art atomic imaging of light elements (i.e., carbon atoms) and individual defects.« less
Processing of insulators and semiconductors
Quick, Nathaniel R.; Joshi, Pooran C.; Duty, Chad Edward; Jellison, Jr., Gerald Earle; Angelini, Joseph Attilio
2015-06-16
A method is disclosed for processing an insulator material or a semiconductor material. The method includes pulsing a plasma lamp onto the material to diffuse a doping substance into the material, to activate the doping substance in the material or to metallize a large area region of the material. The method may further include pulsing a laser onto a selected region of the material to diffuse a doping substance into the material, to activate the doping substance in the material or to metallize a selected region of the material.
Microcapsule and methods of making and using microcapsules
Okawa, David C.; Pastine, Stefan J.; Zettl, Alexander K.; Frechet, Jean M.J.
2014-09-02
An embodiment of a microcapsule includes a shell surrounding a space, a liquid within the shell, and a light absorbing material within the liquid. An embodiment of a method of making microcapsules includes forming a mixture of a light absorbing material and an organic solution. An emulsion of the mixture and an aqueous solution is then formed. A polymerization agent is added to the emulsion, which causes microcapsules to be formed. Each microcapsule includes a shell surrounding a space, a liquid within the shell, and light absorbing material within the liquid. An embodiment of a method of using microcapsules includes providing phototriggerable microcapsules within a bulk material. Each of the phototriggerable microcapsules includes a shell surrounding a space, a chemically reactive material within the shell, and a light absorbing material within the shell. At least some of the phototriggerable microcapsules are exposed to light, which causes the chemically reactive material to release from the shell and to come into contact with bulk material.
Materials for fire resistant passenger seats in aircraft
NASA Technical Reports Server (NTRS)
Tesoro, G.; Moussa, A.
1980-01-01
The paper considers the selection of cushioning foam and upholstery fabric materials for aircraft passenger seats. Polyurethane, polychloroprene, polyimide, and polyphosphazene are the foam materials considered; and a variety of commercial and developmental fabrics (including wool, cotton, synthetics, and blends) are examined. Viable approaches to the design of fire-resistant seat assemblies are indicated. Results of an experimental laboratory study of fabrics and fabric/foam assemblies exposed to external point-source radiative heat flux are discussed.
Hydrogenation of passivated contacts
Nemeth, William; Yuan, Hao-Chih; LaSalvia, Vincenzo; Stradins, Pauls; Page, Matthew R.
2018-03-06
Methods of hydrogenation of passivated contacts using materials having hydrogen impurities are provided. An example method includes applying, to a passivated contact, a layer of a material, the material containing hydrogen impurities. The method further includes subsequently annealing the material and subsequently removing the material from the passivated contact.
Study of process variables associated with manufacturing hermetically-sealed nickel-cadmium cells
NASA Technical Reports Server (NTRS)
Miller, L.
1972-01-01
The effort and results of a program to determine and study the critical process variables associated with the manufacture of aerospace, hermetically-sealed, nickel-cadmium cells are reported. During the period, the impregnation/polarization process variable study was brought to a close with the completion of a series of related experiments. The results of the experiments are summarized. During this period, a general characterization of cell separator materials was initiated. The major conclusions resulting from the characterization of materials are included.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kasten, P.R.; Rittenhouse, P.L.; Bartine, D.E.
1983-06-01
During 1982 the High-Temperature Gas-Cooled Reactor (HTGR) Technology Program at Oak Ridge National Laboratory (ORNL) continued to develop experimental data required for the design and licensing of cogeneration HTGRs. The program involves fuels and materials development (including metals, graphite, ceramic, and concrete materials), HTGR chemistry studies, structural component development and testing, reactor physics and shielding studies, performance testing of the reactor core support structure, and HTGR application and evaluation studies.
Constitutive model for porous materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weston, A.M.; Lee, E.L.
1982-01-01
A simple pressure versus porosity compaction model is developed to calculate the response of granular porous bed materials to shock impact. The model provides a scheme for calculating compaction behavior when relatively limited material data are available. While the model was developed to study porous explosives and propellants, it has been applied to a much wider range of materials. The early development of porous material models, such as that of Hermann, required empirical dynamic compaction data. Erkman and Edwards successfully applied the early theory to unreacted porous high explosives using a Gruneisen equation of state without yield behavior and withoutmore » trapped gas in the pores. Butcher included viscoelastic rate dependance in pore collapse. The theoretical treatment of Carroll and Holt is centered on the collapse of a circular pore and includes radial inertia terms and a complex set of stress, strain and strain rate constitutive parameters. Unfortunately data required for these parameters are generally not available. The model described here is also centered on the collapse of a circular pore, but utilizes a simpler elastic-plastic static equilibrium pore collapse mechanism without strain rate dependence, or radial inertia terms. It does include trapped gas inside the pore, a solid material flow stress that creates both a yield point and a variation in solid material pressure with radius. The solid is described by a Mie-Gruneisen type EOS. Comparisons show that this model will accurately estimate major mechanical features which have been observed in compaction experiments.« less
Mechanical behavior of a ceramic matrix composite material. M.S. Thesis Final Report
NASA Technical Reports Server (NTRS)
Grosskopf, Paul P.; Duke, John C., Jr.
1991-01-01
Monolithic ceramic materials have been used in industry for hundreds of years. These materials have proven their usefulness in many applications, yet, their potential for critical structural applications is limited. The existence of an imperfection in a monolithic ceramic on the order of several microns in size may be critical, resulting in catastrophic failure. To overcome this extreme sensitivity to small material imperfections, reinforced ceramic materials were developed. A ceramic matrix which has been reinforced with continuous fibers is not only less sensitive to microscopic flaws, but is also able to sustain significant damage without suffering catastrophic failure. A borosilicate glass reinforced with several layers of plain weave silicon carbide cloth (Nicalon) was studied. The mechanical testing which was performed included both flexural and tensile loading configurations. This testing was done not only to determine the material properties, but also to initiate a controlled amount of damage within each specimen. Several nondestructive testing techniques, including acousto-ultrasonics (AU), were performed on the specimens periodically during testing. The AU signals were monitored through the use of an IBM compatible personal computer with a high speed data acquisition board. Software was written which manipulates the AU signals in both the time and frequency domains, resulting in quantitative measures of the mechanical response of the material. The measured AU parameters are compared to both the mechanical test results and data from other nondestructive methods including ultrasonic C-scans and penetrant enhanced x ray radiography.
Methods for the additive manufacturing of semiconductor and crystal materials
Stowe, Ashley C.; Speight, Douglas
2016-11-22
A method for the additive manufacturing of inorganic crystalline materials, including: physically combining a plurality of starting materials that are used to form an inorganic crystalline compound to be used as one or more of a semiconductor, scintillator, laser crystal, and optical filter; heating or melting successive regions of the combined starting materials using a directed heat source having a predetermined energy characteristic, thereby facilitating the reaction of the combined starting materials; and allowing each region of the combined starting materials to cool in a controlled manner, such that the desired inorganic crystalline compound results. The method also includes, prior to heating or melting the successive regions of the combined starting materials using the directed heat source, heating the combined starting materials to facilitate initial reaction of the combined starting materials. The method further includes translating the combined starting materials and/or the directed heat source between successive locations. The method still further includes controlling the mechanical, electrical, photonic, and/or optical properties of the inorganic crystalline compound.
Ablation study of tungsten-based nuclear thermal rocket fuel
NASA Astrophysics Data System (ADS)
Smith, Tabitha Elizabeth Rose
The research described in this thesis has been performed in order to support the materials research and development efforts of NASA Marshall Space Flight Center (MSFC), of Tungsten-based Nuclear Thermal Rocket (NTR) fuel. The NTR was developed to a point of flight readiness nearly six decades ago and has been undergoing gradual modification and upgrading since then. Due to the simplicity in design of the NTR, and also in the modernization of the materials fabrication processes of nuclear fuel since the 1960's, the fuel of the NTR has been upgraded continuously. Tungsten-based fuel is of great interest to the NTR community, seeking to determine its advantages over the Carbide-based fuel of the previous NTR programs. The materials development and fabrication process contains failure testing, which is currently being conducted at MSFC in the form of heating the material externally and internally to replicate operation within the nuclear reactor of the NTR, such as with hot gas and RF coils. In order to expand on these efforts, experiments and computational studies of Tungsten and a Tungsten Zirconium Oxide sample provided by NASA have been conducted for this dissertation within a plasma arc-jet, meant to induce ablation on the material. Mathematical analysis was also conducted, for purposes of verifying experiments and making predictions. The computational method utilizes Anisimov's kinetic method of plasma ablation, including a thermal conduction parameter from the Chapman Enskog expansion of the Maxwell Boltzmann equations, and has been modified to include a tangential velocity component. Experimental data matches that of the computational data, in which plasma ablation at an angle shows nearly half the ablation of plasma ablation at no angle. Fuel failure analysis of two NASA samples post-testing was conducted, and suggestions have been made for future materials fabrication processes. These studies, including the computational kinetic model at an angle and the ablation of the NASA sample, could be applied to an atmospheric reentry body, reentering at a ballistic trajectory at hypersonic velocities.
Data Analyses and Modelling for Risk Based Monitoring of Mycotoxins in Animal Feed
van der Fels-Klerx, H.J. (Ine); Adamse, Paulien; Punt, Ans; van Asselt, Esther D.
2018-01-01
Following legislation, European Member States should have multi-annual control programs for contaminants, such as for mycotoxins, in feed and food. These programs need to be risk based implying the checks are regular and proportional to the estimated risk for animal and human health. This study aimed to prioritize feed products in the Netherlands for deoxynivalenol and aflatoxin B1 monitoring. Historical mycotoxin monitoring results from the period 2007–2016 were combined with data from other sources. Based on occurrence, groundnuts had high priority for aflatoxin B1 monitoring; some feed materials (maize and maize products and several oil seed products) and complete/complementary feed excluding dairy cattle and young animals had medium priority; and all other animal feeds and feed materials had low priority. For deoxynivalenol, maize by-products had a high priority, complete and complementary feed for pigs had a medium priority and all other feed and feed materials a low priority. Also including health consequence estimations showed that feed materials that ranked highest for aflatoxin B1 included sunflower seed and palmkernel expeller/extracts and maize. For deoxynivalenol, maize products were ranked highest, followed by various small grain cereals (products); all other feed materials were of lower concern. Results of this study have proven to be useful in setting up the annual risk based control program for mycotoxins in animal feed and feed materials. PMID:29373559
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gruner, Sol
2012-01-20
The primary focus of the grant is the development of new x-ray detectors for biological and materials work at synchrotron sources, especially Pixel Array Detectors (PADs), and the training of students via research applications to problems in biophysics and materials science using novel x-ray methods. This Final Progress Report provides a high-level overview of the most important accomplishments. These major areas of accomplishment include: (1) Development and application of x-ray Pixel Array Detectors; (2) Development and application of methods of high pressure x-ray crystallography as applied to proteins; (3) Studies on the synthesis and structure of novel mesophase materials derivedmore » from block co-polymers.« less
Bhatia, Sujata K; Yetter, Ann B
2008-08-01
Medical devices and implanted biomaterials are often assessed for biological reactivity using visual scores of cell-material interactions. In such testing, biomaterials are assigned cytotoxicity ratings based on visual evidence of morphological cellular changes, including cell lysis, rounding, spreading, and proliferation. For example, ISO 10993 cytotoxicity testing of medical devices allows the use of a visual grading scale. The present study compared visual in vitro cytotoxicity ratings to quantitative in vitro cytotoxicity measurements for biomaterials to determine the level of correlation between visual scoring and a quantitative cell viability assay. Biomaterials representing a spectrum of biological reactivity levels were evaluated, including organo-tin polyvinylchloride (PVC; a known cytotoxic material), ultra-high molecular weight polyethylene (a known non-cytotoxic material), and implantable tissue adhesives. Each material was incubated in direct contact with mouse 3T3 fibroblast cell cultures for 24 h. Visual scores were assigned to the materials using a 5-point rating scale; the scorer was blinded to the material identities. Quantitative measurements of cell viability were performed using a 3-(4,5-dimethylthiozol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay; again, the assay operator was blinded to material identities. The investigation revealed a high degree of correlation between visual cytotoxicity ratings and quantitative cell viability measurements; a Pearson's correlation gave a correlation coefficient of 0.90 between the visual cytotoxicity score and the percent viable cells. An equation relating the visual cytotoxicity score and the percent viable cells was derived. The results of this study are significant for the design and interpretation of in vitro cytotoxicity studies of novel biomaterials.
Effect of heat treatment On Microstructure of steel AISI 01 Tools
NASA Astrophysics Data System (ADS)
Dyanasari Sebayang, Melya; Yudo, Sesmaro Max; Silitonga, Charlie
2018-03-01
This study discusses the influence of quenching, normalizing, and annealing to changes in hardness, tensile, and microstructure of materials tool steel AISI 01 after the material undergo heat treatment process. This heat treatment process includes an initial warming of 600° C and a 5-minute detention time, followed by heating to an austenisation temperature of 850°C. After that a different cooling process, including annealing process, normalizing and quenching oil SAE 40. Tests performed include tensile, hard, and microstructure with shooting using SEM (Scanning Electron Microscope). This is done to see the effect of different heat treatment and cooling process. The result of this research is difference of tensile test value, hard, and micro structure from influence of difference of each process. The quenching process obtains the highest tensile and hard values followed by the normalizing process, annealing, and the lowest is in the starting material, this is because the initial material does not undergo heat treatment process. The resulting microstructure is pearlit and cementite, the difference seen from the shape and size of the grains. The larger the grain size, the greater the hardness.
Complex layered dental restorations: Are they recognizable and do they survive extreme conditions?
Soon, Alistair S; Bush, Mary A; Bush, Peter J
2015-09-01
Recent research has shown that restorative dental materials can be recognized by microscopy and elemental analysis (scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray fluorescence; SEM/EDS and XRF) and that this is possible even in extreme conditions, such as cremation. These analytical methods and databases of dental materials properties have proven useful in DVI (disaster victim identification) of a commercial plane crash in 2009, and in a number of other victim identification cases. Dental materials appear on the market with ever expanding frequency. With their advent, newer methods of restoration have been proposed and adopted in the dental office. Methods might include placing multiple layers of dental materials, where they have different properties including adhesion, viscosity, or working time. These different dental materials include filled adhesives, flowable resins, glass ionomer cements, composite resins, liners and sealants. With possible combinations of different materials in these restorations, the forensic odontologist is now confronted with a new difficulty; how to recognize each individual material. The question might be posed if it is even possible to perform this task. Furthermore, an odontologist might be called upon to identify a victim under difficult circumstances, such as when presented with fragmented or incinerated remains. In these circumstances the ability to identify specific dental materials could assist in the identification of the deceased. Key to use of this information is whether these new materials and methods are detailed in the dental chart. Visual or radiographic inspection may not reveal the presence of a restoration, let alone the possible complex nature of that restoration. This study demonstrates another scientific method in forensic dental identification. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Emerging and potential opportunities for 2D flexible nanoelectronics
NASA Astrophysics Data System (ADS)
Zhu, Weinan; Park, Saungeun; Akinwande, Deji
2016-05-01
The last 10 years have seen the emergence of two-dimensional (2D) nanomaterials such as graphene, transition metal dichalcogenides (TMDs), and black phosphorus (BP) among the growing portfolio of layered van der Waals thin films. Graphene, the prototypical 2D material has advanced rapidly in device, circuit and system studies that has resulted in commercial large-area applications. In this work, we provide a perspective of the emerging and potential translational applications of 2D materials including semiconductors, semimetals, and insulators that comprise the basic material set for diverse nanosystems. Applications include RF transceivers, smart systems, the so-called internet of things, and neurotechnology. We will review the DC and RF electronic performance of graphene and BP thin film transistors. 2D materials at sub-um channel length have so far enabled cut-off frequencies from baseband to 100GHz suitable for low-power RF and sub-THz concepts.
Peng, Qing; Dearden, Albert K; Crean, Jared; Han, Liang; Liu, Sheng; Wen, Xiaodong; De, Suvranu
2014-01-01
Plenty of new two-dimensional materials including graphyne, graphdiyne, graphone, and graphane have been proposed and unveiled after the discovery of the “wonder material” graphene. Graphyne and graphdiyne are two-dimensional carbon allotropes of graphene with honeycomb structures. Graphone and graphane are hydrogenated derivatives of graphene. The advanced and unique properties of these new materials make them highly promising for applications in next generation nanoelectronics. Here, we briefly review their properties, including structural, mechanical, physical, and chemical properties, as well as their synthesis and applications in nanotechnology. Graphyne is better than graphene in directional electronic properties and charge carriers. With a band gap and magnetism, graphone and graphane show important applications in nanoelectronics and spintronics. Because these materials are close to graphene and will play important roles in carbon-based electronic devices, they deserve further, careful, and thorough studies for nanotechnology applications. PMID:24808721
Three-dimensional textures and defects of soft material layering revealed by thermal sublimation.
Yoon, Dong Ki; Kim, Yun Ho; Kim, Dae Seok; Oh, Seong Dae; Smalyukh, Ivan I; Clark, Noel A; Jung, Hee-Tae
2013-11-26
Layering is found and exploited in a variety of soft material systems, ranging from complex macromolecular self-assemblies to block copolymer and small-molecule liquid crystals. Because the control of layer structure is required for applications and characterization, and because defects reveal key features of the symmetries of layered phases, a variety of techniques have been developed for the study of soft-layer structure and defects, including X-ray diffraction and visualization using optical transmission and fluorescence confocal polarizing microscopy, atomic force microscopy, and SEM and transmission electron microscopy, including freeze-fracture transmission electron microscopy. Here, it is shown that thermal sublimation can be usefully combined with such techniques to enable visualization of the 3D structure of soft materials. Sequential sublimation removes material in a stepwise fashion, leaving a remnant layer structure largely unchanged and viewable using SEM, as demonstrated here using a lamellar smectic liquid crystal.
Super Dielectric Material Based Capacitors: Punched Membrane/Gel
NASA Astrophysics Data System (ADS)
Petty, C. W.; Phillips, J.
2018-05-01
Extensive testing showed, as predicted, that punched membranes, filled with a gel containing aqueous salt solutions, behave as superdielectric materials (SDM). Punched membrane superdielectrics employed herein consisted of a commercial cellulose based membrane material, Celgard 16 μ thick, a material frequently used as a separator material in supercapacitors, into which macroscopic holes (ca. 2.5 mm) were punched with a laser cutter, and the holes subsequently filled with a gel-like material composed of fumed silica, NaCl and water. The gross dielectric constants measured, generally > 105, and the energy densities, > 40 J/cm3 during slow discharge, were in the range expected for superdielectric materials. The measured capacitance and energy density tracked the number of holes punched/area filled with the dielectric gel. Also, the observed power law decrease in all parameters including energy, power and capacitance, followed the same trends observed in other classes of SDM. Control studies included testing dielectrics composed of Celgard into which no holes were punched, but the SDM gel spread, also produced values consistent with the SDM model: no measurable capacitance using the standard protocol. Finally, the values measured suggest these materials rival the energy density of some common battery types at low discharge rates, and surpass the best commercial supercapacitors at low discharge rates.
40 CFR 60.1065 - What must I include in my draft materials separation plan?
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 6 2011-07-01 2011-07-01 false What must I include in my draft... Requirements: Materials Separation Plan § 60.1065 What must I include in my draft materials separation plan? (a) You must prepare and submit a draft materials separation plan for your municipal waste combustion unit...
40 CFR 60.1065 - What must I include in my draft materials separation plan?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What must I include in my draft... Requirements: Materials Separation Plan § 60.1065 What must I include in my draft materials separation plan? (a) You must prepare and submit a draft materials separation plan for your municipal waste combustion unit...
40 CFR 60.1065 - What must I include in my draft materials separation plan?
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 7 2014-07-01 2014-07-01 false What must I include in my draft... Requirements: Materials Separation Plan § 60.1065 What must I include in my draft materials separation plan? (a) You must prepare and submit a draft materials separation plan for your municipal waste combustion unit...
40 CFR 60.1065 - What must I include in my draft materials separation plan?
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 7 2013-07-01 2013-07-01 false What must I include in my draft... Requirements: Materials Separation Plan § 60.1065 What must I include in my draft materials separation plan? (a) You must prepare and submit a draft materials separation plan for your municipal waste combustion unit...
40 CFR 60.1065 - What must I include in my draft materials separation plan?
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 7 2012-07-01 2012-07-01 false What must I include in my draft... Requirements: Materials Separation Plan § 60.1065 What must I include in my draft materials separation plan? (a) You must prepare and submit a draft materials separation plan for your municipal waste combustion unit...
Screening combinatorial arrays of inorganic materials with spectroscopy or microscopy
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy
2004-02-03
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Combinatorial synthesis of novel materials
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy
1999-01-01
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Combinatorial sythesis of organometallic materials
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy
2002-07-16
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Polymer arrays from the combinatorial synthesis of novel materials
Schultz, Peter G.; Xiang, Xiao-Dong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong
2004-09-21
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Combinatorial synthesis of novel materials
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy
2002-02-12
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Preparation and screening of crystalline inorganic materials
Schultz, Peter G [La Jolla, CA; Xiang, Xiaodong [Danville, CA; Goldwasser, Isy [Palo Alto, CA; Brice{hacek over }o, Gabriel; Sun, Xiao-Dong [Fremont, CA; Wang, Kai-An [Cupertino, CA
2008-10-28
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Combinatorial synthesis of novel materials
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy
1999-12-21
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Combinatorial synthesis of novel materials
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy
2001-01-01
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Combinatorial screening of inorganic and organometallic materials
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy
2002-01-01
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Preparation and screening of crystalline zeolite and hydrothermally-synthesized materials
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong; Wang, Kai-An
2005-03-08
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Final-impression techniques and materials for making complete and removable partial dentures.
Jayaraman, Srinivasan; Singh, Balendra P; Ramanathan, Balasubramanian; Pazhaniappan Pillai, Murukan; MacDonald, Laura; Kirubakaran, Richard
2018-04-04
Edentulism is relatively common and is often treated with the provision of complete or partial removable dentures. Clinicians make final impressions of complete dentures (CD) and removable partial dentures (RPD) using different techniques and materials. Applying the correct impression technique and material, based on an individual's oral condition, improves the quality of the prosthesis, which may improve quality of life. To assess the effects of different final-impression techniques and materials used to make complete dentures, for retention, stability, comfort, and quality of life in completely edentulous people.To assess the effects of different final-impression techniques and materials used to make removable partial dentures, for stability, comfort, overextension, and quality of life in partially edentulous people. Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 22 November 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Register of Studies, to 22 November 2017), MEDLINE Ovid (1946 to 22 November 2017), and Embase Ovid (21 December 2015 to 22 November 2017). The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on language or publication status when searching the electronic databases, however the search of Embase was restricted by date due to the Cochrane Centralised Search Project to identify all clinical trials and add them to CENTRAL. We included randomised controlled trials (RCTs) comparing different final-impression techniques and materials for treating people with complete dentures (CD) and removable partial dentures (RPD). For CD, we included trials that compared different materials or different techniques or both. In RPD for tooth-supported conditions, we included trials comparing the same material and different techniques, or different materials and the same technique. In tooth- and tissue-supported RPD, we included trials comparing the same material and different dual-impression techniques, and different materials with different dual-impression techniques. Two review authors independently, and in duplicate, screened studies for eligibility, extracted data, and assessed the risk of bias for each included trial. We expressed results as risk ratios (RR) for dichotomous outcomes, and as mean differences (MD) or standardised mean differences (SMD) for continuous outcomes, with 95% confidence intervals (CI), using the random-effects model. We constructed 'Summary of findings' tables for the main comparisons and outcomes (participant-reported oral health-related quality of life, quality of the denture, and denture border adjustments). We included nine studies in this review. Eight studies involved 485 participants with CD. We assessed six of the studies to be at high risk of bias, and two to be at low risk of bias. We judged one study on RPD with 72 randomised participants to be at high risk of bias.Overall, the quality of the evidence for each comparison and outcome was either low or very low, therefore, results should be interpreted with caution, as future research is likely to change the findings.Complete denturesTwo studies compared the same material and different techniques (one study contributed data to a secondary outcome only); two studies compared the same technique and different materials; and four studies compared different materials and techniques.One study (10 participants) evaluated two stage-two step, Biofunctional Prosthetic system (BPS) using additional silicone elastomer compared to conventional methods, and found no evidence of a clear difference for oral health-related quality of life, or quality of the dentures (denture satisfaction). The study reported that BPS required fewer adjustments. We assessed the quality of the evidence as very low.One study (27 participants) compared selective pressure final-impression technique using wax versus polysulfide elastomeric (rubber) material. The study did not measure quality of life or dentures, and found no evidence of a clear difference between interventions in the need for adjustments (RR 0.81, 95% CI 0.38 to 1.70). We assessed the quality of the evidence as very low.One study compared two stage-two step final impression with alginate versus silicone elastomer. Oral health-related quality of life measured by the OHIP-EDENT seemed to be better with silicone (MD 7.20, 95% CI 2.71 to 11.69; 144 participants). The study found no clear differences in participant-reported quality of the denture (comfort) after a two-week 'confirmation' period, but reported that silicone was better for stability and chewing efficiency. We assessed the quality of the evidence as low.Three studies compared single-stage impressions with alginate versus two stage-two step with elastomer (silicone, polysulfide, or polyether) impressions. There was no evidence of a clear difference in the OHIP-EDENT at one month (MD 0.05, 95% CI -2.37 to 2.47; two studies, 98 participants). There was no evidence of a clear difference in participant-rated general satisfaction with dentures at six months (MD 0.00, 95% CI -8.23 to 8.23; one study, 105 participants). We assessed the quality of the evidence as very low.One study compared single-stage alginate versus two stage-two step using zinc-oxide eugenol, and found no evidence of a clear difference in OHIP-EDENT (MD 0.50, 95% CI -2.67 to 3.67; 39 participants), or general satisfaction (RR 3.15, 95% CI 0.14 to 72.88; 39 participants) at six months. We assessed the quality of the evidence as very low.Removable partial denturesOne study randomised 72 participants and compared altered-cast technique versus one-piece cast technique. The study did not measure quality of life, but reported that most participants were satisfied with the dentures and there was no evidence of any clear difference between groups for general satisfaction at one-year follow-up (low-quality evidence). There was no evidence of a clear difference in number of intaglio adjustments at one year (RR 1.43, 95% CI 0.61 to 3.34) (very low-quality evidence). We conclude that there is no clear evidence that one technique or material has a substantial advantage over another for making complete dentures and removable partial dentures. Available evidence for the relative benefits of different denture fabrication techniques and final-impression materials is limited and is of low or very low quality. More high-quality RCTs are required.
Papageorgiou, Spyridon N.; Keilig, Ludger; Hasan, Istabrak; Jäger, Andreas
2016-01-01
Summary Introduction: Biomechanical analysis of orthodontic tooth movement is complex, as many different tissues and appliance components are involved. The aim of this finite element study was to assess the relative effect of material alteration of the various components of the orthodontic appliance on the biomechanical behaviour of tooth movement. Methods: A three-dimensional finite element solid model was constructed. The model consisted of a canine, a first, and a second premolar, including the surrounding tooth-supporting structures and fixed appliances. The materials of the orthodontic appliances were alternated between: (1) composite resin or resin-modified glass ionomer cement for the adhesive, (2) steel, titanium, ceramic, or plastic for the bracket, and (3) β-titanium or steel for the wire. After vertical activation of the first premolar by 0.5mm in occlusal direction, stress and strain calculations were performed at the periodontal ligament and the orthodontic appliance. Results: The finite element analysis indicated that strains developed at the periodontal ligament were mainly influenced by the orthodontic wire (up to +63 per cent), followed by the bracket (up to +44 per cent) and the adhesive (up to +4 per cent). As far as developed stresses at the orthodontic appliance are concerned, wire material had the greatest influence (up to +155 per cent), followed by bracket material (up to +148 per cent) and adhesive material (up to +8 per cent). Limitations: The results of this in silico study need to be validated by in vivo studies before they can be extrapolated to clinical practice. Conclusion: According to the results of this finite element study, all components of the orthodontic fixed appliance, including wire, bracket, and adhesive, seem to influence, to some extent, the biomechanics of tooth movement. PMID:26174769
Quantitative Digital Tomosynthesis Mammography for Improved Breast Cancer Detection and Diagnosis
2008-04-01
include breast-shape slabs consisted of breast- tissue-equivalent materials, i.e. heterogeneous mixture of fibroglandular-tissue- mimicking material. We...collected previ- ously in the Department of Radiology at the University of Michigan for our CAD study.46 The resulting mean effi- ciency ratio for 96 CC...may obscure the characteristics of mass margins. Development of CAD systems for DBT is still at an early stage. In this preliminary study, we compared
1985-09-01
the presence of high concentrations of polychlorinated biphenyls, polynuclear aromatic hydrocarbons , and heavy metals including Cu, 69 - >- j :ij...34Measurement of the Responses of Individuals to Environmental Stress and Pollution: Studies With Bivalve Molluscs ," Philosophical Transactions Royal...Gilfillan, E.S. 1980. "The Use of Scope-for-growth Measurements in Monitoring Petroleum
[Visual representation of biological structures in teaching material].
Morato, M A; Struchiner, M; Bordoni, E; Ricciardi, R M
1998-01-01
Parameters must be defined for presenting and handling scientific information presented in the form of teaching materials. Through library research and consultations with specialists in the health sciences and in graphic arts and design, this study undertook a comparative description of the first examples of scientific illustrations of anatomy and the evolution of visual representations of knowledge on the cell. The study includes significant examples of illustrations which served as elements of analysis.
Effect of processing on Polymer/Composite structure and properties
NASA Technical Reports Server (NTRS)
1982-01-01
Advances in the vitality and economic health of the field of polymer forecasting are discussed. A consistent and rational point of view which considers processing as a participant in the underlying triad of relationships which comprise materials science and engineering is outlined. This triad includes processing as it influences material structure, and ultimately properties. Methods in processing structure properties, polymer science and engineering, polymer chemistry and synthesis, structure and modification and optimization through processing, and methods of melt flow modeling in processing structure property relations of polymer were developed. Mechanical properties of composites are considered, and biomedical materials research to include polymer processing effects are studied. An analysis of the design technology of advances graphite/epoxy composites is also reported.
Coated electroactive materials
Amine, Khalil; Abouimrane, Ali
2016-08-30
A process includes suspending an electroactive material in a solvent, suspending or dissolving a carbon precursor in the solvent; and depositing the carbon precursor on the electroactive material to form a carbon-coated electroactive material. Compositions include a graphene-coated electroactive material prepared from a solution phase mixture or suspension of an electroactive material and graphene, graphene oxide, or a mixture thereof.
Neutron absorbers and methods of forming at least a portion of a neutron absorber
Guillen, Donna P; Porter, Douglas L; Swank, W David; Erickson, Arnold W
2014-12-02
Methods of forming at least a portion of a neutron absorber include combining a first material and a second material to form a compound, reducing the compound into a plurality of particles, mixing the plurality of particles with a third material, and pressing the mixture of the plurality of particles and the third material. One or more components of neutron absorbers may be formed by such methods. Neutron absorbers may include a composite material including an intermetallic compound comprising hafnium aluminide and a matrix material comprising pure aluminum.
The efficiency of the use of composite materials in electrotechnical equipment
NASA Astrophysics Data System (ADS)
Kim, K.; Ivanov, S.
2018-02-01
The indicators of the efficiency of electrical installations are directly connected with the creating and using of new composite materials with the desired performance properties. The practical application of composite materials is one of the perspective scientific and technical directions, providing the increase of the efficiency of electrical installations due to the sealing of current parts by protecting them from the external medium. The technical characteristics of the composite material match to its structure and depend on the properties of the individual components. The verification of the compliance of material parameters is implemented by the methods of the computer analysis of a model of composite material in the form of the structure in which the individual elements have thermodynamic properties of the corresponding phase state. In the study the topology of individual elements in the material structure is defined by the conditional boundaries of the section within the studied composite. The efficiency of using the composite materials includes the raising of electrical safety, increasing the durability, reducing the costs of maintenance and repair and the extension of the scope of installations.
Music of Other Cultures in the Classroom.
ERIC Educational Resources Information Center
Miller, Samuel D.; Brand, Manny
1983-01-01
Studying ethnic music promotes a deeper understanding and acceptance of other peoples and provides an opportunity to study musical concepts. How to choose music materials to enhance social studies is discussed. A brief annotated bibliography is included. (RM)
Evaluation of criteria for developing traffic safety materials for Latinos.
Streit-Kaplan, Erica L; Miara, Christine; Formica, Scott W; Gallagher, Susan Scavo
2011-03-01
This quantitative study assessed the validity of guidelines that identified four key characteristics of culturally appropriate Spanish-language traffic safety materials: language, translation, formative evaluation, and credible source material. From a sample of 190, the authors randomly selected 12 Spanish-language educational materials for analysis by 15 experts. Hypotheses included that the experts would rate materials with more of the key characteristics as more effective (likely to affect behavioral change) and rate materials originally developed in Spanish and those that utilized formative evaluation (e.g., pilot tests, focus groups) as more culturally appropriate. Although results revealed a weak association between the number of key characteristics in a material and the rating of its effectiveness, reviewers rated materials originally created in Spanish and those utilizing formative evaluation as significantly more culturally appropriate. The findings and methodology demonstrated important implications for developers and evaluators of any health-related materials for Spanish speakers and other population groups.
Guerette, Paul A; Hoon, Shawn; Seow, Yiqi; Raida, Manfred; Masic, Admir; Wong, Fong T; Ho, Vincent H B; Kong, Kiat Whye; Demirel, Melik C; Pena-Francesch, Abdon; Amini, Shahrouz; Tay, Gavin Z; Ding, Dawei; Miserez, Ali
2013-10-01
Efforts to engineer new materials inspired by biological structures are hampered by the lack of genomic data from many model organisms studied in biomimetic research. Here we show that biomimetic engineering can be accelerated by integrating high-throughput RNA-seq with proteomics and advanced materials characterization. This approach can be applied to a broad range of systems, as we illustrate by investigating diverse high-performance biological materials involved in embryo protection, adhesion and predation. In one example, we rapidly engineer recombinant squid sucker ring teeth proteins into a range of structural and functional materials, including nanopatterned surfaces and photo-cross-linked films that exceed the mechanical properties of most natural and synthetic polymers. Integrating RNA-seq with proteomics and materials science facilitates the molecular characterization of natural materials and the effective translation of their molecular designs into a wide range of bio-inspired materials.
NASA Technical Reports Server (NTRS)
Bast, Callie Corinne Scheidt
1994-01-01
This thesis presents the on-going development of methodology for a probabilistic material strength degradation model. The probabilistic model, in the form of a postulated randomized multifactor equation, provides for quantification of uncertainty in the lifetime material strength of aerospace propulsion system components subjected to a number of diverse random effects. This model is embodied in the computer program entitled PROMISS, which can include up to eighteen different effects. Presently, the model includes four effects that typically reduce lifetime strength: high temperature, mechanical fatigue, creep, and thermal fatigue. Statistical analysis was conducted on experimental Inconel 718 data obtained from the open literature. This analysis provided regression parameters for use as the model's empirical material constants, thus calibrating the model specifically for Inconel 718. Model calibration was carried out for four variables, namely, high temperature, mechanical fatigue, creep, and thermal fatigue. Methodology to estimate standard deviations of these material constants for input into the probabilistic material strength model was developed. Using the current version of PROMISS, entitled PROMISS93, a sensitivity study for the combined effects of mechanical fatigue, creep, and thermal fatigue was performed. Results, in the form of cumulative distribution functions, illustrated the sensitivity of lifetime strength to any current value of an effect. In addition, verification studies comparing a combination of mechanical fatigue and high temperature effects by model to the combination by experiment were conducted. Thus, for Inconel 718, the basic model assumption of independence between effects was evaluated. Results from this limited verification study strongly supported this assumption.
Perovskite-type catalytic materials for environmental applications.
Labhasetwar, Nitin; Saravanan, Govindachetty; Kumar Megarajan, Suresh; Manwar, Nilesh; Khobragade, Rohini; Doggali, Pradeep; Grasset, Fabien
2015-06-01
Perovskites are mixed-metal oxides that are attracting much scientific and application interest owing to their low price, adaptability, and thermal stability, which often depend on bulk and surface characteristics. These materials have been extensively explored for their catalytic, electrical, magnetic, and optical properties. They are promising candidates for the photocatalytic splitting of water and have also been extensively studied for environmental catalysis applications. Oxygen and cation non-stoichiometry can be tailored in a large number of perovskite compositions to achieve the desired catalytic activity, including multifunctional catalytic properties. Despite the extensive uses, the commercial success for this class of perovskite-based catalytic materials has not been achieved for vehicle exhaust emission control or for many other environmental applications. With recent advances in synthesis techniques, including the preparation of supported perovskites, and increasing understanding of promoted substitute perovskite-type materials, there is a growing interest in applied studies of perovskite-type catalytic materials. We have studied a number of perovskites based on Co, Mn, Ru, and Fe and their substituted compositions for their catalytic activity in terms of diesel soot oxidation, three-way catalysis, N 2 O decomposition, low-temperature CO oxidation, oxidation of volatile organic compounds, etc. The enhanced catalytic activity of these materials is attributed mainly to their altered redox properties, the promotional effect of co-ions, and the increased exposure of catalytically active transition metals in certain preparations. The recent lowering of sulfur content in fuel and concerns over the cost and availability of precious metals are responsible for renewed interest in perovskite-type catalysts for environmental applications.
Perovskite-type catalytic materials for environmental applications
Labhasetwar, Nitin; Saravanan, Govindachetty; Kumar Megarajan, Suresh; Manwar, Nilesh; Khobragade, Rohini; Doggali, Pradeep; Grasset, Fabien
2015-01-01
Perovskites are mixed-metal oxides that are attracting much scientific and application interest owing to their low price, adaptability, and thermal stability, which often depend on bulk and surface characteristics. These materials have been extensively explored for their catalytic, electrical, magnetic, and optical properties. They are promising candidates for the photocatalytic splitting of water and have also been extensively studied for environmental catalysis applications. Oxygen and cation non-stoichiometry can be tailored in a large number of perovskite compositions to achieve the desired catalytic activity, including multifunctional catalytic properties. Despite the extensive uses, the commercial success for this class of perovskite-based catalytic materials has not been achieved for vehicle exhaust emission control or for many other environmental applications. With recent advances in synthesis techniques, including the preparation of supported perovskites, and increasing understanding of promoted substitute perovskite-type materials, there is a growing interest in applied studies of perovskite-type catalytic materials. We have studied a number of perovskites based on Co, Mn, Ru, and Fe and their substituted compositions for their catalytic activity in terms of diesel soot oxidation, three-way catalysis, N2O decomposition, low-temperature CO oxidation, oxidation of volatile organic compounds, etc. The enhanced catalytic activity of these materials is attributed mainly to their altered redox properties, the promotional effect of co-ions, and the increased exposure of catalytically active transition metals in certain preparations. The recent lowering of sulfur content in fuel and concerns over the cost and availability of precious metals are responsible for renewed interest in perovskite-type catalysts for environmental applications. PMID:27877813
NASA Technical Reports Server (NTRS)
Perez-Davis, Marla E.; Gaier, James R.
1990-01-01
In the foreseeable future, an expedition may be undertaken to explore the planet Mars. Some of the power source options being considered for such a mission are photovoltaics, regenerative fuel cells and nuclear reactors. In addition to electrical power requirements, environmental conditions en route to Mars, in the planetary orbit and on the Martian surface must be simulated and studied in order to anticipate and solve potential problems. Space power systems components such as photovoltaic arrays, radiators, and solar concentrators may be vulnerable to degradation in the Martian environment. Natural characteristics of Mars which may pose a threat to surface power systems include high velocity winds, dust, ultraviolet radiation, large daily variation in temperature, reaction to components of the soil, atmosphere and atmospheric condensates as well as synergistic combinations. Most of the current knowledge of the characteristics of the Martian atmosphere and soil composition was obtained from the Viking 1 and 2 missions in 1976. A theoretical study is presented which was used to assess the effects of the Martian atmospheric conditions on the power systems components. A computer program written at NASA-Lewis for combustion research that uses a free energy minimization technique was used to calculate chemical equilibrium for assigned thermodynamic states of temperature and pressure. The power system component materials selected for this study include: silicon dioxide, silicon, carbon, copper, and titanium. Combinations of environments and materials considered include: (1) Mars atmosphere with power surface material, (2) Mars atmosphere and dust component with power surface material, and (3) Mars atmosphere and hydrogen peroxide or superoxide or superoxide with power system material. The chemical equilibrium calculations were performed at a composition ratio (oxidant to reactant) of 100. The temperature for the silicon dioxide material and silicon, which simulate photovoltaic cells, were 300 and 400 K; for carbon, copper and titanium, which simulate radiator surfaces, 300, 500, and 1000 K. All of the systems were evaluated at pressures of 700, 800, and 900 Pa, which stimulate the Martian atmosphere.
The materials processing research base of the Materials Processing Center
NASA Technical Reports Server (NTRS)
Flemings, M. C.; Bowen, H. K.; Kenney, G. B.
1980-01-01
The goals and activities of the center are discussed. The center activities encompass all engineering materials including metals, ceramics, polymers, electronic materials, composites, superconductors, and thin films. Processes include crystallization, solidification, nucleation, and polymer synthesis.
Materials Assessment of Components of the Extravehicular Mobility Unit
NASA Technical Reports Server (NTRS)
Olivas, John D.; Barrera, Enrique V.
1996-01-01
Current research interests for Extravehicular Mobility Unit (EMU) design and development are directed toward enhancements of the Shuttle EMU, implementation of the Mark 3 technology for Shuttle applications, and development of a next generation suit (the X suit) which has applications for prolonged space flight, longer extravehicular activity (EVA), and Moon and Mars missions. In this research project two principal components of the EMU were studied from the vantage point of the materials and their design criteria. An investigation of the flexible materials which make up the lay-up of materials for abrasion and tear protection, thermal insulation, pressure restrain, etc. was initiated. A central focus was on the thermal insulation. A vacuum apparatus for measuring the flexibility of the materials was built to access their durability in vacuum. Plans are to include a Residual Gas Analyzer on the vacuum chamber to measure volatiles during the durability testing. These tests will more accurately simulate space conditions and provide information which has not been available on the materials currently used on the EMU. Durability testing of the aluminized mylar with a nylon scrim showed that the material strength varied in the machine and transverse directions. Study of components of the EMU also included a study of the EMU Bearing Assemblies as to materials selection, engineered materials, use of coatings and flammability issues. A comprehensive analysis of the performance of the current design, which is a stainless steel assembly, was conducted and use of titanium alloys or engineered alloy systems and coatings was investigated. The friction and wear properties are of interest as are the general manufacturing costs. Recognizing that the bearing assembly is subject to an oxygen environment, all currently used materials as well as titanium and engineered alloys were evaluated as to their flammability. An aim of the project is to provide weight reduction since bearing weights constitute 1/3 of the total EMU weight. Our investigations have shown favorable properties using a titanium or nickel base alloy in conjunction with a coating system. Interest lies in developing titanium as a more nonflammable material. Methodology for doing this lies in adding coatings and surface alloying the titanium. This report is brief and does not give all necessary details. The reader should contact the authors as to the detailed study and for viewing of raw data.
Combinatorial synthesis and screening of non-biological polymers
Schultz, Peter G.; Xiang, Xiao-Dong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong; Wang, Kai-An
2006-04-25
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Giant magnetoresistive cobalt oxide compounds
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy
1998-01-01
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Giant magnetoresistive cobalt oxide compounds
Schultz, P.G.; Xiang, X.; Goldwasser, I.
1998-07-07
Methods and apparatus are disclosed for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties. 58 figs.
Synthesis and screening combinatorial arrays of zeolites
Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy
2003-11-18
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
NASA Technical Reports Server (NTRS)
Hofmann, Douglas C. (Inventor); Kennett, Andrew (Inventor)
2018-01-01
Systems and methods to fabricate objects including metallic glass-based materials using low-pressure casting techniques are described. In one embodiment, a method of fabricating an object that includes a metallic glass-based material includes: introducing molten alloy into a mold cavity defined by a mold using a low enough pressure such that the molten alloy does not conform to features of the mold cavity that are smaller than 100 microns; and cooling the molten alloy such that it solidifies, the solid including a metallic glass-based material.
NASA Technical Reports Server (NTRS)
Hofmann, Douglas C. (Inventor); Roberts, Scott N. (Inventor)
2017-01-01
Systems and methods in accordance with embodiments of the invention fabricate objects including metallic glass-based materials using ultrasonic welding. In one embodiment, a method of fabricating an object that includes a metallic glass-based material includes: ultrasonically welding at least one ribbon to a surface; where at least one ribbon that is ultrasonically welded to a surface has a thickness of less than approximately 150.mu.m; and where at least one ribbon that is ultrasonically welded to a surface includes a metallic glass-based material.
A New Direction for NASA Materials Science Research Using the International Space Station
NASA Technical Reports Server (NTRS)
Schlagheck, Ronald; Trach, Brian; Geveden, Rex D. (Technical Monitor)
2001-01-01
NASA recently created a fifth Strategic Enterprise, the Office of Biological and Physical Research (OBPR), to bring together physics, chemistry, biology, and engineering to foster interdisciplinary research. The Materials Science Program is one of five Microgravity Research disciplines within this new enterprise's Division of Physical Sciences Research. The Materials Science Program will participate within this new enterprise structure in order to facilitate effective use of ISS facilities, target scientific and technology questions and transfer scientific and technology results for Earth benefits. The Materials Science research will use a low gravity environment for flight and ground-based research in crystallization, fundamental processing, properties characterization, and biomaterials in order to obtain fundamental understanding of various phenomena effects and relationships to the structures, processing, and properties of materials. Completion of the International Space Station's (ISS) first major assembly, during the past year, provides new opportunities for on-orbit research and scientific utilization. Accommodations will support a variety of Materials Science payload hardware both in the US and international partner modules with emphasis on early use of Express Rack and Glovebox facilities. This paper addresses the current scope of the flight investigator program. These investigators will use the various capabilities of the ISS to achieve their research objectives. The type of research and classification of materials being studied will be addressed. This includes the recent emphasis being placed on nanomaterials and biomaterials type research. Materials Science Program will pursue a new, interdisciplinary approach, which contributes, to Human Space Flight Exploration research. The Materials Science Research Facility (MSRF) and other related American and International experiment modules will serve as the foundation for this research. Discussion will be included to explain the changing concept for materials science research processing capabilities aboard the ISS along with the various ground facilities necessary to support the program. Finally, the paper will address the initial utilization schedule and strategy for the various materials science payloads including their corresponding hardware.
Cell Model Of A Disordered Solid
NASA Technical Reports Server (NTRS)
Peng, Steven T. J.; Landel, Robert F.; Moacanin, Jovan; Simha, Robert; Papazoglou, Elizabeth
1990-01-01
Elastic properties predicted from first principles. Paper discusses generalization of cell theory of disordered (non-crystaline) solid to include anisotropic stresses. Study part of continuing effort to understand macroscopic stress-and-strain properties of solid materials in terms of microscopic physical phenomena. Emphasis on derivation, from first principles, of bulk, shear, and Young's moduli of glassy material at zero absolute temperature.
An Evaluation of Substrates for Tactile Maps and Diagrams: Scanning Speed and Users' Preferences
ERIC Educational Resources Information Center
Jehoel, Sandra; Ungar, Simon; McCallum, Don; Rowell, Jonathan
2005-01-01
This study evaluated the relative suitability of a range of base materials for producing tactile maps and diagrams via a new ink-jet process. The visually impaired and sighted participants tactilely scanned arrays of symbols that were printed on seven substrate materials, including paper, plastic, and aluminum. In general, the rougher substrates…
Children's Freedom: A. S. Neill and the Evolution of the Summerhill Idea.
ERIC Educational Resources Information Center
Hemmings, Ray
This book is a critical evaluation of A. S. Neill's contribution to educational theory and practice. The study includes some biographical material, but this material is introduced to provide a focus for Neill's ideas. The author devotes special attention to Neill's contributions to the psychological aspects of freedom within the social and…
Ewe (for Togo). Special Skills Handbook. Peace Corps Language Handbook Series.
ERIC Educational Resources Information Center
Kozelka, Paul R., Comp.; Agbovi, Yao Ete, Comp.
A book of language and cultural material for teachers and students of Ewe presents vocabulary lists and samples of Ewe language in various contexts, including letters, essays, and newspaper articles. Although not presented in lesson format, the material can be adapted by teachers or used by students for independent study. It is divided into two…
CGF cartridge development, volume 1
NASA Technical Reports Server (NTRS)
Dixon, Carl A.
1993-01-01
This report is a summary of SRI's efforts in Crystal Growth Furnace cartridge developments. It includes: evaluation of molybdenum, TZM, and WC-103 as cartridge materials; a survey of oxidation resistant coatings; chemical compatibility studies of cadmium-zinc-telluride and gallium-arsenide with TZM and WC-103; a survey of future cartridge materials; and suggested improvements in ampoule design.
Analysis of High School English Curriculum Materials through Rasch Measurement Model and Maxqda
ERIC Educational Resources Information Center
Batdi, Veli; Elaldi, Senel
2016-01-01
The purpose of the study is to analyze high school English curriculum materials (ECM) through FACETS analysis and MAXQDA-11 programs. The mixed methods approach, both quantitative and qualitative methods, were used in three samples including English teachers in Elazig during the 2014-2015 academic year. While the quantitative phase of the study…
Adhesive in the buckling failure of corrugated fiberboard : a finite element investigation
Adeeb A. Rahman; Said M. Abubakr
1998-01-01
This research study proposed to include the glue material in a finite element model that represents the actual geometry and material properties of a corrugated fiberboard. The model is a detailed representation of the different components of the structure (adhesive, linerboard, medium) to perform buckling analysis of corrugated structures under compressive loads. The...
Studies in Mathematics, Volume V. Concepts of Informal Geometry. Preliminary Edition.
ERIC Educational Resources Information Center
Anderson, Richard D.
The main purpose of this book is to provide background material in geometry for teachers or prospective teachers who know little or no geometry. It should be suitable as a text for a one-semester course for teachers of junior high school or upper elementary school students. Chapters contain developmental material and exercises. Chapters include:…
ERIC Educational Resources Information Center
Ulu Kalin, Özlem
2017-01-01
Student workbook is an education material including components that support learning, help ensuring knowledge and ability to students in line with the acquisitions stated in teaching programs. Students have different learning styles and necessities. Their needs should be satisfied by benefiting from some additional materials in order to make their…
NASA Technical Reports Server (NTRS)
1979-01-01
Surface coating materials for application on transport type aircraft to reduce drag, were investigated. The investigation included two basic types of materials: spray on coatings and adhesively bonded films. A cost/benefits analysis was performed, and recommendations were made for future work toward the application of this technology.
ERIC Educational Resources Information Center
Wickman, Chad
2010-01-01
This article, drawing on ethnographic study in a chemical physics research facility, explores how notebooks are used and produced in the conduct of laboratory science. Data include written field notes of laboratory activity; visual documentation of "in situ" writing processes; analysis of inscriptions, texts, and material artifacts produced in the…
Heat release rate of wood-plastic composites
N. M. Stark; R. H. White; C. M. Clemons
1997-01-01
Wood-plastic composites are becoming more important as a material that fulfills recycling needs. In this study, fire performance tests were conducted on several compositions of wood and plastic materials using the Ohio State University rate of heat release apparatus. Test results included five-minute average heat release rate in kW/m2 (HRR avg) and maximum heat release...
Tolle, Charles R [Idaho Falls, ID; Clark, Denis E [Idaho Falls, ID; Smartt, Herschel B [Idaho Falls, ID; Miller, Karen S [Idaho Falls, ID
2009-10-06
A material-forming tool and a method for forming a material are described including a shank portion; a shoulder portion that releasably engages the shank portion; a pin that releasably engages the shoulder portion, wherein the pin defines a passageway; and a source of a material coupled in material flowing relation relative to the pin and wherein the material-forming tool is utilized in methodology that includes providing a first material; providing a second material, and placing the second material into contact with the first material; and locally plastically deforming the first material with the material-forming tool so as mix the first material and second material together to form a resulting material having characteristics different from the respective first and second materials.
High Performance High Temperature Thermoelectric Composites with Metallic Inclusions
NASA Technical Reports Server (NTRS)
Firdosy, Samad A. (Inventor); Kaner, Richard B. (Inventor); Ma, James M. (Inventor); Fleurial, Jean-Pierre (Inventor); Star, Kurt (Inventor); Bux, Sabah K. (Inventor); Ravi, Vilupanur A. (Inventor)
2017-01-01
The present invention provides a composite thermoelectric material. The composite thermoelectric material can include a semiconductor material comprising a rare earth metal. The atomic percent of the rare earth metal in the semiconductor material can be at least about 20%. The composite thermoelectric material can further include a metal forming metallic inclusions distributed throughout the semiconductor material. The present invention also provides a method of forming this composite thermoelectric material.
Findikoglu, Alp T [Los Alamos, NM; Jia, Quanxi [Los Alamos, NM; Arendt, Paul N [Los Alamos, NM; Matias, Vladimir [Santa Fe, NM; Choi, Woong [Los Alamos, NM
2009-10-27
A template article including a base substrate including: (i) a base material selected from the group consisting of polycrystalline substrates and amorphous substrates, and (ii) at least one layer of a differing material upon the surface of the base material; and, a buffer material layer upon the base substrate, the buffer material layer characterized by: (a) low chemical reactivity with the base substrate, (b) stability at temperatures up to at least about 800.degree. C. under low vacuum conditions, and (c) a lattice crystal structure adapted for subsequent deposition of a semiconductor material; is provided, together with a semiconductor article including a base substrate including: (i) a base material selected from the group consisting of polycrystalline substrates and amorphous substrates, and (ii) at least one layer of a differing material upon the surface of the base material; and, a buffer material layer upon the base substrate, the buffer material layer characterized by: (a) low chemical reactivity with the base substrate, (b) stability at temperatures up to at least about 800.degree. C. under low vacuum conditions, and (c) a lattice crystal structure adapted for subsequent deposition of a semiconductor material, and, a top-layer of semiconductor material upon the buffer material layer.
Method for manufacturing lightning strike mitigation composites
NASA Technical Reports Server (NTRS)
Vaidyanathan, K. Ranji (Inventor); Campbell, Jeffrey (Inventor)
2012-01-01
A method for manufacturing a composite material utilizes a tooling material having a desired shape. The surface of the tooling material is coated with a composite film that includes a conductive filler material. A composite composition is introduced into contact with the surface of the tooling material to form a desired shape. The composite composition is processed to produce the composite material, and the composite material has a conductive composite surface layer that includes the conductive filler material.
Ajayi, Saheed O; Oyedele, Lukumon O
2018-05-01
Albeit the understanding that construction waste is caused by activities ranging from all stages of project delivery process, research efforts have been concentrated on design and construction stages, while the possibility of reducing waste through materials procurement process is widely neglected. This study aims at exploring and confirming strategies for achieving waste-efficient materials procurement in construction activities. The study employs sequential exploratory mixed method approach as its methodological framework, using focus group discussion, statistical analysis and structural equation modelling. The study suggests that for materials procurement to enhance waste minimisation in construction projects, the procurement process would be characterised by four features. These include suppliers' commitment to low waste measures, low waste purchase management, effective materials delivery management and waste-efficient Bill of Quantity, all of which have significant impacts on waste minimisation. This implies that commitment of materials suppliers to such measures as take back scheme and flexibility in supplying small materials quantity, among others, are expected of materials procurement. While low waste purchase management stipulates the need for such measures as reduced packaging and consideration of pre-assembled/pre-cut materials, efficient delivery management entails effective delivery and storage system as well as adequate protection of materials during the delivery process, among others. Waste-efficient specification and bill of quantity, on the other hand, requires accurate materials take-off and ordering of materials based on accurately prepared design documents and bill of quantity. Findings of this study could assist in understanding a set of measures that should be taken during materials procurement process, thereby corroborating waste management practices at other stages of project delivery process. Copyright © 2018. Published by Elsevier Ltd.
2014-06-01
Northridge earthquake response. The City of Los Angeles and the State of California required contracts to address recycling of demolition materials to the...materials directly recycled and material removed from the site on the enclosed recycling log found within this Contract. Documentation includes...related to recycling disaster debris: “Incentive payment: The City will pay tipping fees using the existing authorization letter; however, only source
Thermal energy storage flight experiments
NASA Technical Reports Server (NTRS)
Namkoong, D.
1989-01-01
Consideration is given to the development of an experimental program to study heat transfer, energy storage, fluid movement, and void location under microgravity. Plans for experimental flight packages containing Thermal Energy Storage (TES) material applicable for advanced solar heat receivers are discussed. Candidate materials for TES include fluoride salts, salt eutectics, silicides, and metals. The development of a three-dimensional computer program to describe TES material behavior undergoing melting and freezing under microgravity is also discussed. The TES experiment concept and plans for ground and flight tests are outlined.
1980-09-01
placement of dredged material is proposed, a quantitative analysis of the effects on the 1-percent chance flood be made. The analysis must include a...FPMWG will accept the site. b. Until a quantitative analysis is conducted, place- ment sites be selected following these guidelines. (1) Dredge4 material... Analysis of site-specific encroachments would continue to be made without considering the opposite bank impacts or the long-term cumulative effects. 5
Battery Electrode Materials with High Cycle Lifetimes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prof. Brent Fultz
2001-06-29
In an effort to understand the capacity fade of nickel-metal hydride (Ni-MH) batteries, we performed a systematic study of the effects of solute additions on the cycle life of metal hydride electrodes. We also performed a series of measurements on hydrogen absorption capacities of novel carbon and graphite-based materials including graphite nanofibers and single-walled carbon nanotubes. Towards the end of this project we turned our attention to work on Li-ion cells with a focus on anode materials.
Terahertz Sensing of Materials
NASA Astrophysics Data System (ADS)
Xuan, G.; Ghosh, S.; Kim, S.; Lv, P.-C.; Buma, T.; Weng, B.; Barner, K.; Kolodzey, J.
2007-06-01
Biomolecules such as DNA and proteins exhibit a wealth of modes in the Terahertz (THz) range from the rotational, vibrational and stretching modes of biomolecules. Many materials such as drywall that are opaque to human eyes are transparent to THz. Therefore, it can be used as a powerful tool for biomolecular sensing, biomedical analysis and through-the-wall imaging. Experiments were carried out to study the absorption of various materials including DNA and see-through imaging of drywall using FTIR spectrometer and Time Domain Spectroscopy (TDS) system.
NASA Technical Reports Server (NTRS)
Sagan, Carl; Thompson, W. Reid; Chyba, Christopher F.; Khare, B. N.
1991-01-01
A review and partial summary of projects within several areas of research generally involving the origin, distribution, chemistry, and spectral/dielectric properties of volatiles and organic materials in the outer solar system and early terrestrial environments are presented. The major topics covered include: (1) impact delivery of volatiles and organic compounds to the early terrestrial planets; (2) optical constants measurements; (3) spectral classification, chemical processes, and distribution of materials; and (4) radar properties of ice, hydrocarbons, and organic heteropolymers.
Strain-Detecting Composite Materials
NASA Technical Reports Server (NTRS)
Wallace, Terryl A. (Inventor); Smith, Stephen W. (Inventor); Piascik, Robert S. (Inventor); Horne, Michael R. (Inventor); Messick, Peter L. (Inventor); Alexa, Joel A. (Inventor); Glaessgen, Edward H. (Inventor); Hailer, Benjamin T. (Inventor)
2016-01-01
A composite material includes a structural material and a shape-memory alloy embedded in the structural material. The shape-memory alloy changes crystallographic phase from austenite to martensite in response to a predefined critical macroscopic average strain of the composite material. In a second embodiment, the composite material includes a plurality of particles of a ferromagnetic shape-memory alloy embedded in the structural material. The ferromagnetic shape-memory alloy changes crystallographic phase from austenite to martensite and changes magnetic phase in response to the predefined critical macroscopic average strain of the composite material. A method of forming a composite material for sensing the predefined critical macroscopic average strain includes providing the shape-memory alloy having an austenite crystallographic phase, changing a size and shape of the shape-memory alloy to thereby form a plurality of particles, and combining the structural material and the particles at a temperature of from about 100-700.degree. C. to form the composite material.
Chang, Liang-Yi; Gershon, Talia S.; Haight, Richard A.; Lee, Yun Seog
2016-12-27
A hybrid vapor phase-solution phase CZT(S,Se) growth technique is provided. In one aspect, a method of forming a kesterite absorber material on a substrate includes the steps of: depositing a layer of a first kesterite material on the substrate using a vapor phase deposition process, wherein the first kesterite material includes Cu, Zn, Sn, and at least one of S and Se; annealing the first kesterite material to crystallize the first kesterite material; and depositing a layer of a second kesterite material on a side of the first kesterite material opposite the substrate using a solution phase deposition process, wherein the second kesterite material includes Cu, Zn, Sn, and at least one of S and Se, wherein the first kesterite material and the second kesterite material form a multi-layer stack of the absorber material on the substrate. A photovoltaic device and method of formation thereof are also provided.
Combinatorial synthesis of inorganic or composite materials
Goldwasser, Isy; Ross, Debra A.; Schultz, Peter G.; Xiang, Xiao-Dong; Briceno, Gabriel; Sun, Xian-Dong; Wang, Kai-An
2010-08-03
Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials or, alternatively, allowing the components to interact to form at least two different materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, nonbiological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.
Material characterisation with methods of nonlinear optics
NASA Astrophysics Data System (ADS)
Prylepa, A.; Reitböck, C.; Cobet, M.; Jesacher, A.; Jin, X.; Adelung, R.; Schatzl-Linder, M.; Luckeneder, G.; Stellnberger, K.-H.; Steck, T.; Faderl, J.; Stehrer, T.; Stifter, D.
2018-01-01
In this review, we present nonlinear optical methods, based on the second and third order nonlinear polarization, especially in the context of material characterization tasks outside the area of life sciences—for which these techniques are mostly designed. An overview of application studies reported to date is given, together with a discussion on the advantages and limits of the individual methods. Furthermore, new ways of experimentally combining different optical concepts are introduced, and their potential for characterisation and inspection tasks is evaluated in the context of various case studies, including the investigation of semiconductor surfaces, metals and related corrosion products, as well as of organic materials.
Modeling of materials supply, demand and prices
NASA Technical Reports Server (NTRS)
1982-01-01
The societal, economic, and policy tradeoffs associated with materials processing and utilization, are discussed. The materials system provides the materials engineer with the system analysis required for formulate sound materials processing, utilization, and resource development policies and strategies. Materials system simulation and modeling research program including assessments of materials substitution dynamics, public policy implications, and materials process economics was expanded. This effort includes several collaborative programs with materials engineers, economists, and policy analysts. The technical and socioeconomic issues of materials recycling, input-output analysis, and technological change and productivity are examined. The major thrust areas in materials systems research are outlined.
Clio's Workshop: Resources for Historical Studies in American Librarianship.
ERIC Educational Resources Information Center
Tucker, John Mark
2000-01-01
Identifies tools most useful in the library historian's workshop, particularly those of a bibliographic, reference, or documentary nature. Highlights include bibliographic tools and the formative years of librarianship; sources of current scholarship; reference sources, including minority voices; documentary materials; and historians in…
Biology Curriculum Support Document.
ERIC Educational Resources Information Center
North Carolina Dept. of Public Instruction, Raleigh.
This biology curriculum supplement includes the North Carolina Standard Course of Study Goals, helpful resources, and suggested activities supported by inquiry-based laboratory activities. Contents include a detailed description of content which provides the goals and standards being sough), a materials list for inquiry support labs and…
Teacher's Guide for Earthworms.
ERIC Educational Resources Information Center
Bruno, Merle S.; And Others
This teacher's guide on earthworms includes four major sections: (1) introduction, (2) caring for earthworms in the classroom, (3) classroom activities, and (4) the appendix. The introduction includes information concerning grade level, scheduling, materials, obtaining earthworms, field study, classroom clean-up, and records. Caring for earthworms…
Modeling of ductile fragmentation that includes void interactions
NASA Astrophysics Data System (ADS)
Meulbroek Fick, J. P.; Ramesh, K. T.; Swaminathan, P. K.
2015-12-01
The failure and fragmentation of ductile materials through the nucleation, growth, and coalescence of voids is important to the understanding of key structural materials. In this model of development effort, ductile fragmentation of an elastic-viscoplastic material is studied through a computational approach which couples these key stages of ductile failure with nucleation site distributions and wave propagation, and predicts fragment spacing within a uniaxial strain approximation. This powerful tool is used to investigate the mechanical and thermal response of OFHC copper at a strain rate of 105. Once the response of the material is understood, the fragmentation of this test material is considered. The average fragment size as well as the fragment size distribution is formulated.
Luo, Min; Song, Zhi-Qin; Yang, Ping-Fei; Liu, Hai; Yang, Zai-Gang; Wu, Ming-Kai
2017-01-01
Using four Uncariae Cum Uncis materials including Uncaria sinensis (HGT), U. hirsutea (MGT), Jianhe U. rhynchophylla (JHGT) and U. rhynchophylla(GT) as the research objects, the correlations between medicinal materials' yield and photosynthetic ecophysiology-factors in the plant exuberant growth period were studied. Results showed that the Uncaria plants net photosynthetic rate (Pn) changed by unimodal curve. There was not "midday depression" phenomenon. There was a different relationship among the photosynthetic ecophysiology-factors and between photosynthetic ecophysiology-factors and medicinal materials' yield. Pn,Tl,Gs had a significant correlation with medicinal materials' yield(M)and were the most important factors of growth. Copyright© by the Chinese Pharmaceutical Association.
Shuttle filter study. Volume 2: Contaminant generation and sensitivity studies
NASA Technical Reports Server (NTRS)
1974-01-01
Contaminant generation studies were conducted at the component level using two different methods, radioactive tracer technique and gravimetric analysis test procedure. Both of these were reduced to practice during this program. In the first of these methods, radioactively tagged components typical of those used in spacecraft were studied to determine their contaminant generation characteristics under simulated operating conditions. Because the purpose of the work was: (1) to determine the types and quantities of contaminants generated; and (2) to evaluate improved monitoring and detection schemes, no attempt was made to evaluate or qualify specific components. The components used in this test program were therefore not flight hardware items. Some of them had been used in previous tests; some were obsolete; one was an experimental device. In addition to the component tests, various materials of interest to contaminant and filtration studies were irradiated and evaluated for use as autotracer materials. These included test dusts, plastics, valve seat materials, and bearing cage materials.
NASA Astrophysics Data System (ADS)
Oses, Corey; Isayev, Olexandr; Toher, Cormac; Curtarolo, Stefano; Tropsha, Alexander
Historically, materials discovery is driven by a laborious trial-and-error process. The growth of materials databases and emerging informatics approaches finally offer the opportunity to transform this practice into data- and knowledge-driven rational design-accelerating discovery of novel materials exhibiting desired properties. By using data from the AFLOW repository for high-throughput, ab-initio calculations, we have generated Quantitative Materials Structure-Property Relationship (QMSPR) models to predict critical materials properties, including the metal/insulator classification, band gap energy, and bulk modulus. The prediction accuracy obtained with these QMSPR models approaches training data for virtually any stoichiometric inorganic crystalline material. We attribute the success and universality of these models to the construction of new materials descriptors-referred to as the universal Property-Labeled Material Fragments (PLMF). This representation affords straightforward model interpretation in terms of simple heuristic design rules that could guide rational materials design. This proof-of-concept study demonstrates the power of materials informatics to dramatically accelerate the search for new materials.
Radiation sensitive devices and systems for detection of radioactive materials and related methods
Kotter, Dale K
2014-12-02
Radiation sensitive devices include a substrate comprising a radiation sensitive material and a plurality of resonance elements coupled to the substrate. Each resonance element is configured to resonate responsive to non-ionizing incident radiation. Systems for detecting radiation from a special nuclear material include a radiation sensitive device and a sensor located remotely from the radiation sensitive device and configured to measure an output signal from the radiation sensitive device. In such systems, the radiation sensitive device includes a radiation sensitive material and a plurality of resonance elements positioned on the radiation sensitive material. Methods for detecting a presence of a special nuclear material include positioning a radiation sensitive device in a location where special nuclear materials are to be detected and remotely interrogating the radiation sensitive device with a sensor.
Removal of cadmium ions from wastewater using innovative electronic waste-derived material.
Xu, Meng; Hadi, Pejman; Chen, Guohua; McKay, Gordon
2014-05-30
Cadmium is a highly toxic heavy metal even at a trace level. In this study, a novel material derived from waste PCBs has been applied as an adsorbent to remove cadmium ions from aqueous solutions. The effects of various factors including contact time, initial cadmium ion concentration, pH and adsorbent dosage have been evaluated. The maximum uptake capacity of the newly derived material for cadmium ions has reached 2.1mmol/g at an initial pH 4. This value shows that this material can effectively remove cadmium ions from effluent. The equilibrium isotherm has been analyzed using several isotherm equations and is best described by the Redlich-Peterson model. Furthermore, different commercial adsorbent resins have been studied for comparison purposes. The results further confirm that this activated material is highly competitive with its commercial counterparts. Copyright © 2014 Elsevier B.V. All rights reserved.
Health Promotion at the Construction Work Site: The Lunch Truck Pilot Study.
Caban-Martinez, Alberto J; Moore, Kevin J; Clarke, Tainya C; Davila, Evelyn P; Clark, John D; Lee, David J; Fleming, Lora E
2018-04-01
The transient nature of construction work makes it difficult to conduct longitudinal worksite-based health promotion activities. As part of a workplace health assessment pilot study, we worked with a commercial lunch truck company to disseminate four types of health education materials including cancer screening, workplace injury prevention, fruit and vegetable consumption, and smoking cessation to construction workers purchasing food items from the truck during their job breaks. Two weeks following the worksite assessment, we followed up with these workers to ascertain their use of the health promotion materials. Of the 54 workers surveyed, 83% reported reviewing and sharing the cancer screening materials with their families, whereas 44% discussed the cancer screening materials with coworkers. Similar proportions of workers reviewed, shared, and discussed the other health promotion materials with their family. Lunch trucks may be an effective strategy and delivery method for educating construction workers on healthy behaviors and injury prevention practices.
Submersion Quenching of Undercooled Liquid Metals in an Electrostatic Levitator
NASA Technical Reports Server (NTRS)
SanSoucie, Michael P.; Rogers, Jan R.
2016-01-01
The NASA Marshall Space Flight Center (MSFC) electrostatic levitation (ESL) laboratory has a long history of providing materials research and thermophysical property data. The laboratory has recently added a new capability, a rapid quench system. This system allows samples to be dropped into a quench vessel that can be filled with a low melting point material, such as a gallium or indium alloy. Thereby allowing rapid quenching of undercooled liquid metals and alloys. This is the first submersion quench system inside an electrostatic levitator. The system has been tested successfully with samples of zirconium, iron-cobalt alloys, titanium-zirconium-nickel alloys, and silicon-cobalt alloys. This rapid quench system will allow materials science studies of undercooled materials and new materials development, including studies of metastable phases and transient microstructures. In this presentation, the system is described and some initial results are presented.
Effects of combustibles on internal quasi-static loads
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sandoval, N.R.; Hokanson, J.C.; Esparza, E.D.
1984-08-01
The phenomenon of quasi-static pressure enhancement produced when combustible materials are placed near HE sources has been recently discovered. The effects of placing solid and liquid combustible materials near detonating explosives on internal blast loading was measured during tests conducted in a one-eighth scale model of a containment structure. In many cases, dramatic increases in gas pressures resulted. Principal conclusions of this study are: combustible materials near explosives can markedly increase gas pressures in enclosed structures; there is a lack of data on HE-combustible combinations; quasi-static loading calculations should include estimates of contributions from the burning of combustible materials whenevermore » such materials are expected to be in intimate contact with HE sources; and effects of combustibles should be investigated further to determine methods for prediction. Variations in charge to combustible mass, charge type, structure volume, degree of venting and degree of contact between HE and combustible sbould be studied.« less
Influence of dental materials on cells of the equine periodontium.
Ringeisen, H; Pöschke, A; Krähling, B; Schröck, C; Stoll, M; Vogelsberg, J; Failing, K; Staszyk, C
2018-05-01
Therapy for equine periodontal disease can include filling of the periodontal pockets and widened interproximal spaces. Recommended dental materials are generally adopted from human dentistry. To evaluate the biocompatibility of dental materials for equine periodontal fillings in vitro. In vitro experiments. Four different dental materials (PeriCare ® , Provicol ® , Calxyl ® and Honigum) were tested on equine periodontal fibroblasts. Possible cytotoxic effects were assessed microscopically and by MTT assay, and the expression of inflammatory marker genes was measured by qRT-PCR. PeriCare ® and Provicol ® had no effects on the cells, whereas Honigum and Calxyl ® were associated with severe cytotoxic effects. The results of this in vitro study need to be confirmed by clinical studies. Before adapting dental materials from human dentistry, it is crucial to initially test them in a specific equine model. © 2017 EVJ Ltd.
NASA Astrophysics Data System (ADS)
Pinney, Nathan Douglas
Due to their high surface area and reactivity toward a variety of heavy metal and oxyanion species of environmental concern, Fe-(oxyhydr)oxide materials play an important role in the geochemical fate of natural and anthropogenic contaminants in soils, aquifers and surface water environments worldwide. In this research, ab initio simulations describe the bulk structure, magnetic properties, and relative phase stability of major Fe-(oxyhydr)oxide materials, including hematite, goethite, lepidocrocite, and ferrihydrite.These bulk models are employed in further studies of point defect and alloy/dopant thermodynamics in these materials, allowing construction of a phase stability model that better replicates the structure and composition of real materials. Li + adsorption at the predominant goethite (101) surface is simulated using ab initio methods, offering energetic and structural insight into the binding mechanisms of metal cations over a range of surface protonation conditions.
Functional organic materials for electronics industries
NASA Technical Reports Server (NTRS)
Shibayama, K.; Ono, H.
1982-01-01
Topics closely related with organic, high molecular weight material synthesis are discussed. These are related to applications such as display, recording, sensors, semiconductors, and I.C. correlation. New materials are also discussed. General principles of individual application are not included. Materials discussed include color, electrochromic, thermal recording, organic photoconductors for electrophotography, and photochromic materials.
Mineral trioxide aggregate: part 2 - a review of the material aspects.
Malhotra, Neeraj; Agarwal, Antara; Mala, Kundabala
2013-03-01
The purpose of this two-part series is to review the composition, properties, and products of mineral trioxide aggregate (MTA) materials. PubMed and MedLine electronic databases were used to identify scientific papers from January 1991 to May 2010. Based on the selected inclusion criteria, citations were referenced from the scientific peer-reviewed dental literature. Mineral trioxide aggregate is a refined form of the parent compound, Portland cement (PC), and demonstrates a strong biocompatibility due to the high pH level and the material's ability to form hydroxyapatite. Mineral trioxide aggregate materials provide better microleakage protection than traditional endodontic materials as observed in findings from dye-leakage, fluid-filtration, protein-leakage, and bacterial penetration-leakage studies and has been recognized as a bioactive material. Various MTA commercial products are available, including gray mineral trioxide aggregate (GMTA), white mineral trioxide aggregate (WMTA), and mineral trioxide aggregate-Angelus (AMTA). Although these materials are indicated for various dental uses and applications, long-term in-vivo clinical studies are needed. Part 1 of this article highlighted and discussed the composition and characteristics of the material. Part 2 provides an overview of commercially available MTA materials.
Material and energy dependence of services and its implications for climate change.
Nansai, Keisuke; Kagawa, Shigemi; Suh, Sangwon; Fujii, Minoru; Inaba, Rokuta; Hashimoto, Seiji
2009-06-15
As the services industry has grown and diversified, there has been a rapid rise in the share of energy and material costs in provision of services. As a result, services, which have traditionally been considered immaterial by their nature, are now absorbing substantial amounts of energy and material goods. By decomposing the CO2 emissions embodied in material goods and services, this study quantitatively analyzes the implications of energy and materials consumption in services for the change in indirect CO2 emissions by household consumers in Japan. The results show that the domestic CO2 emissions associated with the energy and material goods absorbed by services through the supply chain increased consistently during the decade 1990-2000, thereby constituting a key element in the rise in CO2 emissions due to household consumption. The energy and materials within the supply chain underlying services that have been identified as the main causes of this increase include electric power consumption, petroleum products, building renovation and repair, distribution of printed materials, plastic products and water, all of which are necessary to support the services in question. This study highlights the increasing importance of energy and materials consumption by services in the context of climate change policy.
Waste Reduction Model (WARM) Material Descriptions and ...
2017-02-14
This page provides a summary of the materials included in EPA’s Waste Reduction Model (WARM). The page includes a list of materials, a description of the material as defined in the primary data source, and citations for primary data sources.
Experimental methods for identifying failure mechanisms
NASA Technical Reports Server (NTRS)
Daniel, I. M.
1983-01-01
Experimental methods for identifying failure mechanisms in fibrous composites are studied. Methods to identify failure in composite materials includes interferometry, holography, fractography and ultrasonics.
Community Air Monitoring Training in July 2015. Topics included motivaton, goals, data quality and quantity, recruitment of other citizen scientists, technology requirements, supporting materials, and evaluations.
Asian Americans and materialism: Exploring the phenomenon and its why and when.
Zhang, Jia Wei
2018-05-24
Consumer values, including but not limited to materialism, have received much less attention than other topics within research on Asian Americans. Across 3 studies (N = 6,955), the author explored the difference between Asian Americans and White/European Americans on materialism, and the mediating and moderating mechanisms. Studies 1a-1c found Asian Americans, compared to White/European Americans, more strongly endorsed materialistic values. In Study 2, the author tested a multiple mediation model and demonstrated that Asian Americans, compared to White/European Americans, more strongly endorse materialistic values because they reported higher extrinsic aspirations (i.e., stronger desires for money, image, and popularity). Finally, in Study 3, the author tested a moderation model and found that Asian Americans who are higher on a general tendency to adhere to norms endorse a greater level of materialism than White/European Americans. The author discussed how these results have implications for expanding the research topics within research on Asian Americans, consequences for mental health and provide future directions to counteract materialism. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Production of activated carbon by using pyrolysis process in an ammonia atmosphere
NASA Astrophysics Data System (ADS)
Indayaningsih, N.; Destyorini, F.; Purawiardi, R. I.; Insiyanda, D. R.; Widodo, H.
2017-04-01
Activated carbon is materials that have wide applications, including supercapacitor materials, absorbent in chemical industry, and absorbent material in the chemical industry. This study has carried out for the manufacturing of activated carbon from inexpensive materials through efficient processes. Carbon material was made from coconut fibers through pyrolysis process at temperature of 650, 700, 750 and 800°C. Aim of this study was to obtain carbon material that has a large surface area. Pyrolysis process is carried out in an inert atmosphere (N2 gas) at a temperature of 450°C for 30 minutes, followed by pyrolysis process in an ammonia atmosphere at 800°C for 2 hours. The pyrolysis results showed that the etching process in ammonia is occurred; as it obtained some greater surface area when compared with the pyrolisis process in an atmosphere by inert gas only. The resulted activated carbon also showed to have good properties in surface area and total pore volume.
Drummond, Gail; Bevan, Ruth; Harrison, Paul
2016-11-01
The aim of this paper is to compare results from inhalation studies with those from intraperitoneal and intrapleural tests, where available, for a number of fibrous and particulate test materials. The objective is to determine how well intraperitoneal/intrapleural studies predict the pathological responses observed in more standard in vivo studies of pulmonary toxicity, with a particular focus on carcinogenicity. Published toxicity data was obtained for a number of materials including asbestos, wollastonite, MMVFs (including glass fibres, stone wools and RCF), silicon carbide whiskers, potassium octatitanate, quartz, kevlar, polypropylene and titanium dioxide. For some of the fibrous material reviewed, there is conformity between the results of intraperitoneal and inhalation tests such that they are either consistently positive or consistently negative. For the remaining fibrous materials reviewed, intraperitoneal and inhalation tests give different results, with positive results in the intraperitoneal test not being reflected by positive inhalation results. It is suggested that the intraperitoneal test can be used to exonerate a dust or fibre (because if negative in the intraperitoneal test it is extremely unlikely to be positive in either inhalation or intratracheal tests) but should not be used to positively determine that a dust or fibre is carcinogenic by inhalation. We would argue against the use of intraperitoneal tests for human health risk assessment except perhaps for the purpose of exoneration of a material from classification as a carcinogen. Copyright © 2016 Elsevier Inc. All rights reserved.
Chemical transport during formation and alteration of Martian impact and volcanic deposits
NASA Technical Reports Server (NTRS)
Newsom, H. E.
1992-01-01
Much of the surface of Mars, including volcanic and cratered terrains, probably experienced alteration and degassing processes. These processes may have depleted or enriched many important elements in surface materials, including bedrock, dust, and soils. The composition of the martian soil may represent the best estimate, for some elements, of the average composition of the martian crust, similar to the composition of loess created by glacial action on the Earth. The martian soil may represent the only convenient, globally or regionally averaged sample of the martian crust. In order to understand the composition of the source material for the soil, however, we need to understand the contributions of volcanic vs. impact sources for this material and the chemical fractionations involved in its production. The processes to be addressed include degassing of volcanic deposits, as observed in the Valley of Ten Thousand Smokes at Katmai, Alaska, and degassing of meltbearing impact ejecta as inferred for suevite ejecta sheets at the Ries Crater, and alteration or palagonitization of volcanic deposits, as documented for volcanos in British Columbia and many other volcanic terrains, and impact crater deposits. The process of palagonitization has been the subject of several studies with reference to Mars, and palagonite is a good analogue for the spectroscopic properties of the martian dust. The role of impact in cratering has not been as well studied, although other researchers have established that both degassing and alteration are common features of impact crater deposits. Other relevant sources of experimental data include the extensive literature on the corrosion of nuclear waste glass and leaching of shocked materials.
Experiments Developed to Study Microgravity Smoldering Combustion
NASA Technical Reports Server (NTRS)
Vergilii, Franklin
2001-01-01
The overall objective of the Microgravity Smoldering Combustion (MSC) research program is to understand and predict smoldering combustion under normal and microgravity (near-zero-gravity) conditions to help prevent and control smolder-originated fires, in both environments. Smoldering is defined as a nonflaming, self-sustaining, propagating, exothermic surface reaction. If a material is sufficiently permeable, smoldering is not confined to its outer surface, but can propagate as a reaction wave through the interior of the material. The MSC program will accomplish its goals by conducting smolder experiments on the ground and in a space-based laboratory, and developing theoretical models of the process. Space-based experiments are necessary because smoldering is a very slow process and, consequently, its study in a microgravity environment requires extended periods of time that can only be achieved in space. Smoldering can occur in a variety of processes ranging from the smolder of porous insulating materials to underground coal combustion. Many materials can sustain smoldering, including wood, cloth, foams, tobacco, other dry organic materials, and charcoal. The ignition, propagation, transition to flaming, and extinction of the smolder reaction are controlled by complex, thermochemical mechanisms that are not well understood. As with many forms of combustion, gravity affects the availability of the oxidizer and the transport of heat, and therefore, the rate of combustion. The smoldering combustion of porous materials has been studied both experimentally and theoretically, usually in the context of fire safety. Smoldering encompasses a number of fundamental processes, including heat and mass transfer in a porous media; endothermic pyrolysis of combustible material; ignition, propagation, and extinction of heterogeneous exothermic reactions at the solid-gas pore interface; and the onset of gas phase reactions (flaming) from existing surface reactions. Smoldering presents a serious fire risk because the combustion can propagate slowly in a material's interior and go undetected for long periods of time. It typically yields a substantially higher conversion of fuel to toxic compounds than does flaming (though more slowly), and may undergo a sudden transition to flaming.