Search for magnetic monopoles in lunar material

NASA Technical Reports Server (NTRS)

Alvarez, L. W.; Eberhard, P. H.; Ross, R. R.; Watt, R. D.

1972-01-01

Magnetic monopoles in 19.8 kg. of lunar material returned by Apollo 11, 12 and 14 missions were investigated. The search was done with a detector which is capable of detecting any single monopole of any charge equal to or larger than the minimum value compatible with Dirac's theory. Two experiments were performed, each one with different lunar material. In each experiment the lunar material was divided into several measurement samples. No monopole was found. The magnetic charge of each sample was consistent with zero.

Investigation of microgravity effects on solidification phenomena of selected materials

NASA Technical Reports Server (NTRS)

Maag, Carl R.; Hansen, Patricia A.

1992-01-01

A Get Away Special (GAS) experiment payload to investigate microgravity effects on solidification phenomena of selected experimental samples has been designed for flight. It is intended that the first flight of the assembly will (1) study the p-n junction characteristics for advancing semiconductor device applications, (2) study the effects of gravity-driven convection on the growth of HgCd crystals, (3) compare the textures of the sample which crystallizes in microgravity with those found in chondrite meteorites, and (4) modify glass optical characteristics through divalent oxygen exchange. The space flight experiment consists of many small furnaces. While the experiment payload is in the low gravity environment of orbital flight, the payload controller will sequentially activate the furnaces to heat samples to their melt state and then allow cooling to resolidification in a controlled fashion. The materials processed in the microgravity environment of space will be compared to the same materials processed on earth in a one-gravity environment. This paper discusses the design of all subassemblies (furnance, electronics, and power systems) in the experiment. A complete description of the experimental materials is also presented.

Investigating Bandgap Energies, Materials, and Design of Light-Emitting Diodes

ERIC Educational Resources Information Center

Wagner, Eugene P., II

2016-01-01

A student laboratory experiment to investigate the intrinsic and extrinsic bandgaps, dopant materials, and diode design in light-emitting diodes (LEDs) is presented. The LED intrinsic bandgap is determined by passing a small constant current through the diode and recording the junction voltage variation with temperature. A second visible…

Ongoing Inquiry

ERIC Educational Resources Information Center

Ashbrook, Peggy

2011-01-01

An in-depth science inquiry is an ongoing investigation in which children are introduced to materials through hands-on experiences and, with teacher guidance, begin to investigate a question that they can answer through their own actions, observations, and with teacher-assisted research. Qualities that make an experience appropriate to include in…

Advanced thermal batteries

NASA Astrophysics Data System (ADS)

Ryan, D. M.

1980-03-01

The feasibility of building thermal batteries with cells composed of an anode of LiAl alloy, a cathode of a heavy metal chloride, and a NaAlCl4 electrolyte has been demonstrated. During the further investigation of this system some interesting problems have developed and had to be studied. The particle size growth of the catholyte developed into a major storage problem. MoCl5 was found to form a volatile catholyte which is not suited for thermal battery use. As a result of this problem other catholyte materials were experimented with. CuCl2 is the most successful alternate to MoCl5. Some alternate binder materials have been investigated: kaolin clay, Illinois Mineral Amorphous Silica, and magnesia. Some alternate electrolytes have been investigated including NaAlCl4 (containing 52 m/o AlCl3), LiAlCl4 and KCl-LiCl. This work indicates that each material has unique properties which lend themselves to a particular application. Among the alternate cathode materials experimented with are CrCl3, a number of heavy metal oxides, fluorocarbon, TiS2, TiS3, and sulfur. Some alternate process investigated have been freon blending, adding materials to the anode, cell and battery desiccation and filling batteries with an inert atmosphere.

Organic Materials in the Undergraduate Laboratory: Microscale Synthesis and Investigation of a Donor-Acceptor Molecule

ERIC Educational Resources Information Center

Pappenfus, Ted M.; Schliep, Karl B.; Dissanayake, Anudaththa; Ludden, Trevor; Nieto-Ortega, Belen; Lopez Navarrete, Juan T.; Ruiz Delgado, M. Carmen; Casado, Juan

2012-01-01

A series of experiments for undergraduate courses (e.g., organic, physical) have been developed in the area of small molecule organic materials. These experiments focus on understanding the electronic and redox properties of a donor-acceptor molecule that is prepared in a convenient one-step microscale reaction. The resulting intensely colored…

Experimental Investigation on Thermal Physical Properties of an Advanced Polyester Material

NASA Astrophysics Data System (ADS)

Guangfa, Gao; Shujie, Yuan; Ruiyuan, Huang; Yongchi, Li

Polyester materials were applied widely in aircraft and space vehicles engineering. Aimed to an advanced polyester material, a series of experiments for thermal physical properties of this material were conducted, and the corresponding performance curves were obtained through statistic analyzing. The experimental results showed good consistency. And then the thermal physical parameters such as thermal expansion coefficient, engineering specific heat and sublimation heat were solved and calculated. This investigation provides an important foundation for the further research on the heat resistance and thermodynamic performance of this material.

Examination of lignocellulosic fibers for chemical, thermal, and separations properties: Addressing thermo-chemical stability issues

NASA Astrophysics Data System (ADS)

Johnson, Carter David

Natural fiber-plastic composites incorporate thermoplastic resins with fibrous plant-based materials, sometimes referred to as biomass. Pine wood mill waste has been the traditional source of natural fibrous feedstock. In anticipation of a waste wood shortage other fibrous biomass materials are being investigated as potential supplements or replacements. Perennial grasses, agricultural wastes, and woody biomass are among the potential source materials. As these feedstocks share the basic chemical building blocks; cellulose, hemicellulose, and lignin, they are collectively called lignocellulosics. Initial investigation of a number of lignocellulosic materials, applied to fiber-plastic composite processing and material testing, resulted in varied results, particularly response to processing conditions. Less thermally stable lignocellulosic filler materials were physically changed in observable ways: darkened color and odor. The effect of biomass materials' chemical composition on thermal stability was investigated an experiment involving determination of the chemical composition of seven lignocellulosics: corn hull, corn stover, fescue, pine, soy hull, soy stover, and switchgrass. These materials were also evaluated for thermal stability by thermogravimetric analysis. The results of these determinations indicated that both chemical composition and pretreatment of lignocellulosic materials can have an effect on their thermal stability. A second study was performed to investigate what effect different pretreatment systems have on hybrid poplar, pine, and switchgrass. These materials were treated with hot water, ethanol, and a 2:1 benzene/ethanol mixture for extraction times of: 1, 3, 6, 12, and 24 hours. This factorial experiment demonstrated that both extraction time and medium have an effect on the weight percent of extractives removed from all three material types. The extracted materials generated in the above study were then subjected to an evaluation of thermal stability by thermogravimetric analysis in a subsequent experiment. Overlay plots, combining individual weight loss curves, demonstrate that the experimental factors, solvent system and extraction time, produce effects on the thermal stability of the treated biomass samples. These data also indicated that the individual lignocellulosic materials had unique responses to the type of solvent used for pretreatment. Increasing extraction time had either no correlation with or a positive effect on thermal stability of the biomass samples.

Material Science Experiments on Mir

NASA Technical Reports Server (NTRS)

Kroes, Roger L.

1999-01-01

This paper describes the microgravity materials experiments carried out on the Shuttle/Mir program. There were six experiments, all of which investigated some aspect of diffusivity in liquid melts. The Liquid Metal Diffusion (LMD) experiment investigated the diffusivity of molten Indium samples at 185 C using a radioactive tracer, In-114m. By monitoring two different gamma ray energies (190 keV and 24 keV) emitted by the samples it was possible to measure independently the diffusion rates in the bulk and at the surface of the samples. The Queens University Experiment in Liquid Diffusion (QUELD) was the furnace facility used to process 213 samples for the five other experiments. These experiments investigated the diffusion, ripening, crystal growth, and glass formation in metal, semiconductor, and glass samples. This facility had the capability to process samples in an isothermal or gradient configuration for varying periods of time at temperatures up to 900 C. Both the LMD and the QUELD furnaces were mounted on the Microgravity Isolation Mount (MIM) which provided isolation from g-jitter. All the microgravity experiments were supported by the Space Acceleration Measurement System (SAMS); a three head three axes acceleration monitoring system which measured and recorded the acceleration environment.

Material Science

NASA Image and Video Library

2003-01-22

Dr. Richard Grugel, a materials scientist at NASA's Marshall Space Flight in Huntsville, Ala., examines the furnace used to conduct his Pore Formation and Mobility Investigation -- one of the first two materials science experiments to be conducted on the International Space Station. This experiment studies materials processes similar to those used to make components used in jet engines. Grugel's furnace was installed in the Microgravity Science Glovebox through the circular port on the side. In space, crewmembers are able to change out samples using the gloves on the front of the facility's work area.

On the cyclic stress-strain behavior and low cycle fatigue of aerospace materials

NASA Technical Reports Server (NTRS)

Burbach, J.

1972-01-01

The elastic-plastic deformation behavior under cyclic stress of a number of different engineering materials was experimentally investigated with the aid of high-precision methods of measuring, some of which had been newly developed. Experiments made with a variety of steels, the titanium alloy Ti-A16-V4, a cobalt (tungsten) alloy, the high-temperature material Nimonic 90 and Dural (A1-Cu) are reported. The theory given in an attempt to explain these experiments is aimed at finding general formulas for the cyclic stress-strain behavior materials.

The experiment research of the friction sliding isolation structure

NASA Astrophysics Data System (ADS)

Zhang, Shirong; Li, Jiangle; Wang, Sheliang

2018-04-01

This paper investigated the theory of the friction sliding isolation structure, The M0S2 solid lubricant was adopted as isolation bearing friction materials, and a new sliding isolation bearing was designed and made. The formula of the friction factor and the compression stress was proposed. The feasibility of the material MoS2 used as the coating material in a friction sliding isolation system was tested on the 5 layers concrete frame model. Two application experiment conditions were presented. The results of the experiment research indicated that the friction sliding isolation technology have a good damping effect.

Simple Experiments on Magnetism and Electricity...from Edison.

ERIC Educational Resources Information Center

Schultz, Robert F.

Background information, lists of materials needed and procedures used are provided for 16 simple experiments on electricity and magnetism. These experiments are organized into sections dealing with: (1) Edison's carbon experiments (building a galvanometer, investigating the variable conductivity of carbon, and examining the carbon transmitter…

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.

STS-94 Mission Specialist Thomas in LC-39A White Room

NASA Technical Reports Server (NTRS)

1997-01-01

STS-94 Mission Specialist Donald A. Thomas prepares to enter the Space Shuttle Columbia at Launch Pad 39A in preparation for launch. He has flown on STS-83, STS-70 and STS-65. He holds a doctorate in materials science and has been the Principal Investigator for a Space Shuttle crystal growth experiment. Because of his background in materials science, Thomas will be concentrating his efforts during the Red shift on the five experiments in this discipline in the Large Isothermal Furnace. He also will work on the ten materials science investigations in the Electromagnetic Containerless Processing Facility and four that will be measuring the effects of microgravity and motion in the orbiter on the experiments. Thomas and six fellow crew members will lift off during a launch window that opens at 1:50 a.m. EDT, July opportunity to lift off before Florida summer rain showers reach the space center.

KSC-97pc561

NASA Image and Video Library

1997-04-04

STS-83 Mission Specialist Donald A. Thomas is assisted into his launch/entry suit in the Operations and Checkout (O&C) Building. He has flown on both STS-70 and STS-65. He holds a doctorate in materials science and has been the Principal Investigator for a Space Shuttle crystal growth experiment. Because of his background in materials science, Thomas will be concentrating his efforts during the Red shift on the five experiments in this discipline in the large Isothermal Furnace. He also will work on the ten materials science investigations in the Electromagnetic Containerless Processing Facility and four that will be measuring the effects of microgravity and motion in the orbiter on the experiments. Thomas and six fellow crew members will shortly depart the O&C and head for Launch Pad 39A, where the Space Shuttle Columbia will lift off during a launch window that opens at 2:00 pm EST, April 4

Investigation of materials for inert electrodes in aluminum electrodeposition cells

NASA Astrophysics Data System (ADS)

Haggerty, J. S.; Sadoway, D. R.

1987-09-01

Work was divided into major efforts. The first was the growth and characterization of specimens; the second was Hall cell performance testing. Cathode and anode materials were the subject of investigation. Preparation of specimens included growth of single crystals and synthesis of ultra high purity powders. Special attention was paid to ferrites as they were considered to be the most promising anode materials. Ferrite anode corrosion rates were studied and the electrical conductivities of a set of copper-manganese ferrites were measured. Float Zone, Pendant Drop Cryolite Experiments were undertaken because unsatisfactory choices of candidate materials were being made on the basis of a flawed set of selection criteria applied to an incomplete and sometimes inaccurate data base. This experiment was then constructed to determine whether the apparatus used for float zone crystal growth could be adapted to make a variety of important based melts and their interactions with candidate inert anode materials. Compositions), driven by our perception that the basis for prior selection of candidate materials was inadequate. Results are presented.

Thermal - Hydraulic Behavior of Unsaturated Bentonite and Sand-Bentonite Material as Seal for Nuclear Waste Repository: Numerical Simulation of Column Experiments

NASA Astrophysics Data System (ADS)

Ballarini, E.; Graupner, B.; Bauer, S.

2015-12-01

For deep geological repositories of high-level radioactive waste (HLRW), bentonite and sand bentonite mixtures are investigated as buffer materials to form a a sealing layer. This sealing layer surrounds the canisters and experiences an initial drying due to the heat produced by HLRW and a successive re-saturation with fluid from the host rock. These complex thermal, hydraulic and mechanical processes interact and were investigated in laboratory column experiments using MX-80 clay pellets as well as a mixture of 35% sand and 65% bentonite. The aim of this study is to both understand the individual processes taking place in the buffer materials and to identify the key physical parameters that determine the material behavior under heating and hydrating conditions. For this end, detailed and process-oriented numerical modelling was applied to the experiments, simulating heat transport, multiphase flow and mechanical effects from swelling. For both columns, the same set of parameters was assigned to the experimental set-up (i.e. insulation, heater and hydration system), while the parameters of the buffer material were adapted during model calibration. A good fit between model results and data was achieved for temperature, relative humidity, water intake and swelling pressure, thus explaining the material behavior. The key variables identified by the model are the permeability and relative permeability, the water retention curve and the thermal conductivity of the buffer material. The different hydraulic and thermal behavior of the two buffer materials observed in the laboratory observations was well reproduced by the numerical model.

Overview of NASA's Microgravity Materials Science Program

NASA Technical Reports Server (NTRS)

Downey, James Patton

2012-01-01

The microgravity materials program was nearly eliminated in the middle of the aughts due to budget constraints. Hardware developments were eliminated. Some investigators with experiments that could be performed using ISS partner hardware received continued funding. Partnerships were established between US investigators and ESA science teams for several investigations. ESA conducted peer reviews on the proposals of various science teams as part of an ESA AO process. Assuming he or she was part of a science team that was selected by the ESA process, a US investigator would submit a proposal to NASA for grant funding to support their part of the science team effort. In a similar manner, a US materials investigator (Dr. Rohit Trivedi) is working as a part of a CNES selected science team. As funding began to increase another seven materials investigators were selected in 2010 through an NRA mechanism to perform research related to development of Materials Science Research Rack investigations. One of these has since been converted to a Glovebox investigation.

Physics of Granular Materials: Investigations in Support of Astrobiology

NASA Technical Reports Server (NTRS)

Marshall, John R.

2002-01-01

This publication list is submitted as a summary of the work conducted under Cooperative Agreement 1120. The goal of the 1120 research was to study granular materials within a planetary, astrophysical, and astrobiological context. This involved research on the physical, mechanical and electrostatic properties of granular systems, as well as the examination of these materials with atomic force microscopy and x-ray analysis. Instruments for analyzing said materials in planetary environments were developed, including the MECA (Mars Environment Compatibility Assessment) experiment for the MSP '01 lander, the ECHOS/MATADOR experiment for the MSP '03 lander, an ISRU experiment for the '03 lander, and MiniLEAP technology. Flight experiments for microgravity (Space Station and Shuttle) have also been developed for the study of granular materials. As expressed in the publications, work on 1120 encompassed laboratory research, theoretical modeling, field experiments, and flight experiments: a series of successful new models were developed for understanding the behavior of triboelectrostatically charged granular masses, and 4 separate instruments were selected for space flight. No inventions or patents were generated by the research under this Agreement.

Ionic Liquids and Green Chemistry: A Lab Experiment

ERIC Educational Resources Information Center

Stark, Annegret; Ott, Denise; Kralisch, Dana; Kreisel, Guenter; Ondruschka, Bernd

2010-01-01

Although ionic liquids have been investigated as solvents for many applications and are starting to be used in industrial processes, only a few lab experiments are available to introduce students to these materials. Ionic liquids have been discussed in the context of green chemistry, but few investigations have actually assessed the degree of…

Containerless experiments in fluid physics in microgravity

NASA Technical Reports Server (NTRS)

Trinh, E. H.

1990-01-01

The physical phenomena associated with the behavior of liquid samples freely suspended in low gravity must be thoroughly understood prior to undertaking detailed scientific studies of the materials under scrutiny. The characteristics of molten specimens under the action of containerless positioning stresses must be identified and separated from the specific phenomena relating to the absence of an overwhelming gravitational field. The strategy designed to optimize the scientific return of reliable experimental data from infrequent microgravity investigations should include the gradual and logical phasing of more sophisticated studies building on the accumulated results from previous flight experiments. Lower temperature fluid physics experiments using model materials can provide a great deal of information that can be useful in analyzing the behavior of high temperature melts. The phasing of the experimental capabilities should, therefore, also include a gradual build-up of more intricate and specialized diagnostic instrumentation and environmental control and monitoring capabilities. Basic physical investigations should also be distinguished from specific materials technology issues. The latter investigations require very specific high temperature (and high vacuum) devices that must be thoroughly mastered on the ground prior to implementing them in space.

Inductive Learning: Does Interleaving Exemplars Affect Long-Term Retention?

ERIC Educational Resources Information Center

Zulkiply, Norehan; Burt, Jennifer S.

2013-01-01

Purpose: The present study investigated whether or not the benefits of interleaving of exemplars from several categories vary with retention interval in inductive learning. Methodology: Two experiments were conducted using paintings (Experiment 1) and textual materials (Experiment 2), and the experiments used a mixed factorial design. Forty…

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.

Selected results for LDEF thermal control coatings

NASA Technical Reports Server (NTRS)

Golden, Johnny L.

1993-01-01

Several different thermal control coatings were analyzed as part of the Long Duration Exposure Facility (LDEF) Materials Special Investigation Group activity and as part of the Space Environment Effects on Spacecraft Materials Experiment M0003. A brief discussion of the results obtained for these materials is presented.

Experimental Investigation on Thermal Physical Properties of an Advanced Glass Fiber Composite Material

NASA Astrophysics Data System (ADS)

Guangfa, Gao; Yongchi, Li; Zheng, Jing; Shujie, Yuan

Fiber reinforced composite materials were applied widely in aircraft and space vehicles engineering. Aimed to an advanced glass fiber reinforced composite material, a series of experiments for measuring thermal physical properties of this material were conducted, and the corresponding performance curves were obtained through statistic analyzing. The experimental results showed good consistency. And then the thermal physical parameters such as thermal expansion coefficient, engineering specific heat and sublimation heat were solved and calculated. This investigation provides an important foundation for the further research on the heat resistance and thermodynamic performance of this material.

Experimental analysis of quasi-static and dynamic fracture initiation toughness of gy4 armor steel material

NASA Astrophysics Data System (ADS)

Ren, Peng; Guo, Zitao

Quasi-static and dynamic fracture initiation toughness of gy4 armour steel material are investigated using three point bend specimen. The modified split Hopkinson pressure bar (SHPB) apparatus with digital image correlation (DIC) system is applied to dynamic loading experiments. Full-field deformation measurements are obtained by using DIC to elucidate on the strain fields associated with the mechanical response. A series of experiments are conducted at different strain rate ranging from 10-3 s-1 to 103 s-1, and the loading rate on the fracture initiation toughness is investigated. Specially, the scanning electron microscope imaging technique is used to investigate the fracture failure micromechanism of fracture surfaces. The gy4 armour steel material fracture toughness is found to be sensitive to strain rate and higher for dynamic loading as compared to quasi-static loading. This work is supported by National Nature Science Foundation under Grant 51509115.

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.

More Bits and Pieces: A Second Physics Miscellany

ERIC Educational Resources Information Center

Siddons, J. C.

1976-01-01

Described are five physics experiments utilizing inexpensive, readily available materials or materials normally found in a physics laboratory. Included are investigations of electrical charge, sound detection, thermal expansion, doppler effects, and the cycloid. (SL)

Material Science

NASA Image and Video Library

2003-01-22

Video images sent to the ground allow scientists to watch the behavior of the bubbles as they control the melting and freezing of the material during the Pore Formation and Mobility Investigation (PFMI) in the Microgravity Science Glovebox aboard the International Space Station. While the investigation studies the way that metals behave at the microscopic scale on Earth -- and how voids form -- the experiment uses a transparent material called succinonitrile that behaves like a metal to study this problem. The bubbles do not float to the top of the material in microgravity, so they can study their interactions.

The Microgravity Research Experiments (MICREX) Data Base

NASA Technical Reports Server (NTRS)

Winter, C. A.; Jones, J. C.

1996-01-01

An electronic data base identifying over 800 fluids and materials processing experiments performed in a low-gravity environment has been created at NASA Marshall Space Flight Center. The compilation, called MICREX (MICrogravity Research Experiments) was designed to document all such experimental efforts performed (1) on U.S. manned space vehicles, (2) on payloads deployed from U.S. manned space vehicles, and (3) on all domestic and international sounding rockets (excluding those of China and the former U.S.S.R.). Data available on most experiments include (1) principal and co-investigator (2) low-gravity mission, (3) processing facility, (4) experimental objectives and results, (5) identifying key words, (6) sample materials, (7) applications of the processed materials/research area, (8) experiment descriptive publications, and (9) contacts for more information concerning the experiment. This technical memorandum (1) summarizes the historical interest in reduced-gravity fluid dynamics, (2) describes the importance of a low-gravity fluids and materials processing data base, (4) describes thE MICREX data base format and computational World Wide Web access procedures, and (5) documents (in hard-copy form) the descriptions of the first 600 fluids and materials processing experiments entered into MICREX.

The Microgravity Research Experiments (MICREX) Data Base. Volume 2

NASA Technical Reports Server (NTRS)

Winter, C. A.; Jones, J. C.

1996-01-01

An electronic data base identifying over 800 fluids and materials processing experiments performed in a low-gravity environment has been created at NASA Marshall Space Flight Center. The compilation, called MICREX (MICrogravity Research Experiments), was designed to document all such experimental efforts performed (1) on U.S. manned space vehicles, (2) on payloads deployed from U.S. manned space vehicles, and (3) on all domestic and international sounding rockets (excluding those of China and the former U.S.S.R.). Data available on most experiments include (1) principal and co-investigators (2) low-gravity mission, (3) processing facility, (4) experimental objectives and results, (5) identifying key words, (6) sample materials, (7) applications of the processed materials/research area, (8) experiment descriptive publications, and (9) contacts for more information concerning the experiment. This technical memorandum (1) summarizes the historical interest in reduced-gravity fluid dynamics, (2) describes the experimental facilities employed to examine reduced gravity fluid flow, (3) discusses the importance of a low-gravity fluids and materials processing data base, (4) describes the MICREX data base format and computational World Wide Web access procedures, and (5) documents (in hard-copy form) the descriptions of the first 600 fluids and materials processing experiments entered into MICREX.

The Microgravity Research Experiments (MICREX) Data Base. Volume 1

NASA Technical Reports Server (NTRS)

Winter, C. A.; Jones, J.C.

1996-01-01

An electronic data base identifying over 800 fluids and materials processing experiments performed in a low-gravity environment has been created at NASA Marshall Space Flight Center. The compilation, called MICREX (MICrogravity Research Experiments), was designed to document all such experimental efforts performed (1) on U.S. manned space vehicles, (2) on payloads deployed from U.S. manned space vehicles, and (3) on all domestic and international sounding rockets (excluding those of China and the former U.S.S.R.). Data available on most experiments include (1) principal and co-investigators, (2) low-gravity mission, (3) processing facility, (4) experimental objectives and results, (5) identifying key words, (6) sample materials, (7) applications of the processed materials/research area, (8) experiment descriptive publications, and (9) contacts for more information concerning the experiment. This technical memorandum (1) summarizes the historical interest in reduced-gravity fluid dynamics, (2) describes the experimental facilities employed to examine reduced gravity fluid flow, (3) discusses the importance of a low-gravity fluids and materials processing data base, (4) describes the MICREX data base format and computational World Wide Web access procedures, and (5) documents (in hard-copy form) the descriptions of the first 600 fluids and materials processing experiments entered into MICREX.

The Microgravity Research Experiments (MICREX) Data Base, Volume 4

NASA Technical Reports Server (NTRS)

Winter, C. A.; Jones, J. C.

1996-01-01

An electronic data base identifying over 800 fluids and materials processing experiments performed in a low-gravity environment has been created at NASA Marshall Space Flight Center. The compilation, called MICREX (MICrogravity Research Experiments), was designed to document all such experimental efforts performed (1) on U.S. manned space vehicles, (2) on payloads deployed from U.S. manned space vehicles, and (3) on all domestic and international sounding rockets (excluding those of China and the former U.S.S.R.). Data available on most experiments include (1) principal and co-investigators (2) low-gravity mission, (3) processing facility, (4) experimental objectives and results, (5) identifying key words, (6) sample materials, (7) applications of the processed materials/research area, (8) experiment descriptive publications, and (9) contacts for more information concerning the experiment. This technical Memorandum (1) summarizes the historical interest in reduced-gravity fluid dynamics, (2) describes the importance of a low-gravity fluids and materials processing data base, (4) describes the MICREX data base format and computational World Wide Web access procedures, and (5) documents (in hard-copy form) the descriptions of the first 600 fluids and materials processing experiments entered into MICREX.

Multispectral analysis of ocean dumped materials

NASA Technical Reports Server (NTRS)

Johnson, R. W.

1977-01-01

Remotely sensed data were collected in conjunction with sea-truth measurements in three experiments in the New York Bight. Pollution features of primary interest were ocean dumped materials, such as sewage sludge and acid waste. Sewage-sludge and acid-waste plumes, including plumes from sewage sludge dumped by the 'line-dump' and 'spot-dump' methods, were located, identified, and mapped. Previously developed quantitative analysis techniques for determining quantitative distributions of materials in sewage sludge dumps were evaluated, along with multispectral analysis techniques developed to identify ocean dumped materials. Results of these experiments and the associated data analysis investigations are presented and discussed.

Correlation between cavitation erosion resistance and cyclic mechanical properties of different metallic materials

NASA Astrophysics Data System (ADS)

Kaufhold, Corinna; Pöhl, Fabian; Theisen, Werner

2017-05-01

Machine components in contact with flowing fluids are especially prone to cavitation erosion, where plastic deformation and material loss occur due to the repeated implosion of cavitation bubbles in the vicinity of a solid surface. Identifying a correlation between experimentally derivable material properties and resistance against cavitation erosion could help improve the lifetime of cavitation-affected components. Cavitation erosion is a predominantly fatigue-driven phenomenon. In this investigation, we conducted nanoindentation experiments to examine cyclic micromechanical material properties in response to an increasing number of cycles. The experiments were performed on pure iron and different steel grades, i.e., austenitic stainless CrMnCN steels, interstitially alloyed with carbon and nitrogen. We confirmed the view, also proposed in literature, that indentation hardness is inappropriate for ordering the investigated materials by incubation period or maximum erosion rate. We found that the percentage increase of nanoindentation contact stiffness, after an increasing number of cycles, is a promising indicator in terms of the overall ranking of cavitation erosion resistance among the considered materials. Although a single cavitation impact is associated with a significantly higher strain rate than nanoindentation experiments, it is shown that the plastically deformed area around each indent exhibits indications of deformation, such as the formation of slip lines that are also observable after cavitation-induced impacts.

Space Weathering Experiments on Spacecraft Materials

NASA Technical Reports Server (NTRS)

Cooper, R.; Cowardin, H.; Engelhar, D.; Plis, Elena; Hoffman, R.

2017-01-01

A project to investigate space environment effects on specific materials with interest to remote sensing was initiated in 2016. The goal of the project is to better characterize changes in the optical properties of polymers and Mylar, specifically those found in multi-layered spacecraft insulation, due to electron bombardment. Previous analysis shows that chemical bonds break and potentially reform when exposed to high energy electrons. Among other properties these chemical changes altered the optical reflectance as documented in laboratory analysis. This paper presents results of the initial experiment results focused on the exposure of materials to various fluences of high energy electrons, used to simulate a portion of the geosynchronous space environment. The paper illustrates how the spectral reflectance changes as a function of time on orbit with respect to GEO environmental factors and investigates the survivability of the material after multiple electron doses. These results provide a baseline for analysis of aging effects on satellite systems used for remote sensing. They also provide preliminary analysis on what materials are most likely to encompass the high area-to-mass population of space debris in the geosynchronous environment. Lastly, the paper provides the results of the initial experimentation as a proof of concept for space aging on polymers and Mylar for conducting more experiments with a larger subset of spacecraft materials.

Designing Web-Based Educative Curriculum Materials for the Social Studies

ERIC Educational Resources Information Center

Callahan, Cory; Saye, John; Brush, Thomas

2013-01-01

This paper reports on a design experiment of web-based curriculum materials explicitly created to help social studies teachers develop their professional teaching knowledge. Web-based social studies curriculum reform efforts, human-centered interface design, and investigations into educative curriculum materials are reviewed, as well as…

Materials processing in space: An introduction to the G-480 payload

NASA Technical Reports Server (NTRS)

Butow, Steven J.

1988-01-01

The Space Research and Development Organization at San Jose State University designed and developed a small self-contained payload (designated G-480 by NASA) which will perform four materials science experiments in low Earth orbit aboard the Space Shuttle. These experiments are categorized under two areas of investigation: corrosion and electrodeposition. While none of these experiments have previously been performed in space, both government and industry have expressed great interest in these and related areas of materials processing and engineering. A brief history of the G-480 project development is given along with a description of each experiment, followed by a tour of the G-480 payload. Expected results are discussed along with the function, design and operation of the payload hardware and software.

Experiments Conducted Aboard the International Space Station: The Pore Formation and Mobility Investigation (PFMI) and the In-Space Soldering Investigation (ISSI): A Current Study of Results

NASA Technical Reports Server (NTRS)

Grugel, R. N.; Luz, P.; Smith, G. A.; Spivey, R.; Jeter, L.; Gillies, D. C> ; Hua, F.; Anilkumar, A. V.

2006-01-01

Experiments in support of the Pore Formation and Mobility Investigation (PFMI) and the In-Space Soldering Investigation (ISSI) were conducted aboard the International Space Station (ISS) with the goal of promoting our fundamental understanding of melting dynamics , solidification phenomena, and defect generation during materials processing in a microgravity environment. Through the course of many experiments a number of observations, expected and unexpected, have been directly made. These include gradient-driven bubble migration, thermocapillary flow, and novel microstructural development. The experimental results are presented and found to be in good agreement with models pertinent to a microgravity environment. Based on the space station results, and noting the futility of duplicating them in Earth s unit-gravity environment, attention is drawn to the role ISS experimentslhardware can play to provide insight to potential materials processing techniques and/or repair scenarios that might arise during long duration space transport and/or on the lunar/Mars surface.

Calcium carbonate scale control, effect of material and inhibitors.

PubMed

Macadam, J; Parsons, S A

2004-01-01

This paper focuses on developing a reproducible method for reducing calcium carbonate scale formation on heated surfaces where scaling can cause serious problems. It is known that calcium carbonate precipitation is sensitive to impurity ions, such as iron and zinc, even at trace concentration levels. In this paper two sets of experiments are reported. The first experiments were undertaken to investigate the effect of zinc, copper and iron dosing on CaCO3 nucleation and precipitation. Results from the experiments showed that the most effective inhibitor of CaCO3 precipitation was zinc and the effect was linked to dose levels and temperature. Copper and iron had little effect on precipitation in the dose range investigated. The second trial was undertaken to translate the precipitation data to scale formation. These tests were undertaken at 70 degrees C. 5 mg x L(-1) zinc dose reduced the scale formation by 35%. The effect of iron on calcium carbonate scaling rate was not significant. The physical nature of the material on which the scale is formed also influences the scaling. The scaling experiment was also used to investigate the effect of different surface material (stainless steel, copper and aluminium) on CaCO3 scale formation. Copper surface scaled the most.

Material Science

NASA Image and Video Library

2003-01-22

On Earth when scientists melt metals, bubbles that form in the molten material can rise to the surface, pop and disappear. In microgravity -- the near-weightless environment created as the International Space Station orbits Earth -- the lighter bubbles do not rise and disappear. Prior space experiments have shown that bubbles often become trapped in the final metal or crystal sample -similar to the bubbles trapped in this sample. In the solid, these bubbles, or porosity, are defects that diminish both the material's strength and usefulness. The Pore Formation and Mobility Investigation will melt samples of a transparent modeling material, succinonitrile and succinonitrile water mixtures, shown here in an ampoule being examined by Dr. Richard Grugel, the principal investigator for the experiment at NASA's Marshall Space Flight Center in Huntsville, Ala. As the samples are processed in space, Grugel will be able to observe how bubbles form in the samples and study their movements and interactions.

Fabrication of aerogel capsule, bromine-doped capsule, and modified gold cone in modified target for the Fast Ignition Realization Experiment (FIREX) Project

NASA Astrophysics Data System (ADS)

Nagai, Keiji; Yang, H.; Norimatsu, T.; Azechi, H.; Belkada, F.; Fujimoto, Y.; Fujimura, T.; Fujioka, K.; Fujioka, S.; Homma, H.; Ito, F.; Iwamoto, A.; Jitsuno, T.; Kaneyasu, Y.; Nakai, M.; Nemoto, N.; Saika, H.; Shimoyama, T.; Suzuki, Y.; Yamanaka, K.; Mima, K.

2009-09-01

The development of target fabrication for the Fast Ignition Realization EXperiment (FIREX) Project is described in this paper. For the first stage of the FIREX Project (FIREX-I), the previously designed target has been modified by using a bromine-doped ablator and coating the inner gold cone with a low-density material. A high-quality bromine-doped capsule without vacuoles was fabricated from bromine-doped deuterated polystyrene. The gold surface was coated with a low-density material by electrochemical plating. For the cryogenic fuel target, a brand new type of aerogel material, phloroglucinol/formaldehyde (PF), was investigated and encapsulated to meet the specifications of 500 µm diameter and 20 µm thickness, with 30 nm nanopores. Polystyrene-based low-density materials were investigated and the relationship between the crosslinker content and the nanopore structure was observed.

Investigation of crystal growth in zero gravity environment and investigation of metallic whiskers

NASA Technical Reports Server (NTRS)

Davis, J. H.; Lal, R. B.; Walter, H. U.; Castle, J. G., Jr.

1972-01-01

Theoretical and experimental work reported relates to the effects of near-zero gravity on growths of crystals and metallic whiskers during Skylab and Apollo flight experiments. Studies on growth and characterization of candidate materials for flight experiments cover indium-bismuth compounds, bismuth single crystals, gallium arsenide films and single crystals, and cadmium whiskers.

The Effects of Aural versus Notated Instructional Materials on Achievement and Self-Efficacy in Jazz Improvisation

ERIC Educational Resources Information Center

Watson, Kevin E.

2010-01-01

The purpose of the present study was to investigate the effects of aural versus notated pedagogical materials on achievement and self-efficacy in instrumental jazz improvisation performance. A secondary purpose of this study was to investigate how achievement and self-efficacy may be related to selected experience variables. The sample for the…

Material Science

NASA Image and Video Library

2003-01-22

One of the first materials science experiments on the International Space Station -- the Solidification Using a Baffle in Sealed Ampoules (SUBSA) -- will be conducted during Expedition Five inside the Microgravity Science Glovebox. The glovebox is the first dedicated facility delivered to the Station for microgravity physical science research, and this experiment will be the first one operated inside the glovebox. The glovebox's sealed work environment makes it an ideal place for the furnace that will be used to melt semiconductor crystals. Astronauts can change out samples and manipulate the experiment by inserting their hands into a pair of gloves that reach inside the sealed box. Dr. Aleksandar Ostrogorsky, a materials scientist from the Rensselaer Polytechnic Institute, Troy, N.Y., and the principal investigator for the SUBSA experiment, uses the gloves to examine an ampoule like the ones used for his experiment inside the glovebox's work area. The Microgravity Science Glovebox and the SUBSA experiment are managed by NASA's Marshall Space Flight Center in Huntsville, Ala.

Pore Formation and Mobility Investigation video images

NASA Technical Reports Server (NTRS)

2003-01-01

Video images sent to the ground allow scientists to watch the behavior of the bubbles as they control the melting and freezing of the material during the Pore Formation and Mobility Investigation (PFMI) in the Microgravity Science Glovebox aboard the International Space Station. While the investigation studies the way that metals behave at the microscopic scale on Earth -- and how voids form -- the experiment uses a transparent material called succinonitrile that behaves like a metal to study this problem. The bubbles do not float to the top of the material in microgravity, so they can study their interactions.

Impact of materials used in lab and field experiments on the recovery of organic micropollutants

NASA Astrophysics Data System (ADS)

Hebig, Klaus; Nödler, Karsten; Licha, Tobias; Scheytt, Traugott

2015-04-01

Organic micropollutants are frequently detected in the aquatic environment. There-fore, a large number of field and laboratory studies have been conducted in order to study their fate in the environment. Due to the diversity of chemical properties among these compounds some of them may interact with materials commonly used in field and laboratory studies like tubes, filters, or sample bottles. The aim of our experiment was to study the interaction between those materials and an aqueous solution of 43 widely detected basic, neutral, and acidic organic micropollutants hereby covering a broad range of polarities. Experiments with materials were conducted as a batch study using spiked tap water and for different syringe filters by filtration with subsequent fraction collection. The best recoveries over a wide range of organic compounds were observed for batches in contact with the following materials (in descending order) acryl glass, PTFE, HDPE, and PP. The use of Pharmed©, silicone, NBR70, Tygon©, and LDPE should be avoided. Flexible tubing materials especially influence many of the investigated compounds here. Filtration with most of the tested filter types leads to no significant loss of almost all of the investigated micropollutants. Nonetheless, significant mass losses of some compounds (loratadine, fluoxetine, sertraline, and diuron) were observed during the first mL of the filtration process. No systematic correlation between compound properties, tested materials, and ob-served mass losses could be identified in this study. The behavior of each compound is specific and thus, not predictable. It is therefore suggested to study the interaction of compounds with filters and material prior to the actual experiment or include blank studies.

Investigation of Springback Associated with Composite Material Component Fabrication (MSFC Center Director's Discretionary Fund Final Report, Project 94-09)

NASA Technical Reports Server (NTRS)

Benzie, M. A.

1998-01-01

The objective of this research project was to examine processing and design parameters in the fabrication of composite components to obtain a better understanding and attempt to minimize springback associated with composite materials. To accomplish this, both processing and design parameters were included in a Taguchi-designed experiment. Composite angled panels were fabricated, by hand layup techniques, and the fabricated panels were inspected for springback effects. This experiment yielded several significant results. The confirmation experiment validated the reproducibility of the factorial effects, error recognized, and experiment as reliable. The material used in the design of tooling needs to be a major consideration when fabricating composite components, as expected. The factors dealing with resin flow, however, raise several potentially serious material and design questions. These questions must be dealt with up front in order to minimize springback: viscosity of the resin, vacuum bagging of the part for cure, and the curing method selected. These factors directly affect design, material selection, and processing methods.

Using the Tritium Plasma Experiment to evaluate ITER PFC safety

NASA Astrophysics Data System (ADS)

Longhurst, Glen R.; Anderl, Robert A.; Bartlit, John R.; Causey, Rion A.; Haines, John R.

The Tritium Plasma Experiment was assembled at Sandia National Laboratories, Livermore to investigate interactions between dense plasmas at low energies and plasma-facing component materials. This apparatus has the unique capability of replicating plasma conditions in a tokamak divertor with particle flux densities of 2 x 10(exp 19) ions/((sq cm)(s)) and a plasma temperature of about 15 eV using a plasma that includes tritium. With the closure of the Tritium Research Laboratory at Livermore, the experiment was moved to the Tritium Systems Test Assembly facility at Los Alamos National Laboratory. An experimental program has been initiated there using the Tritium Plasma Experiment to examine safety issues related to tritium in plasma-facing components, particularly the ITER divertor. Those issues include tritium retention and release characteristics, tritium permeation rates and transient times to coolant streams, surface modification and erosion by the plasma, the effects of thermal loads and cycling, and particulate production. A considerable lack of data exists in these areas for many of the materials, especially beryllium, being considered for use in ITER. Not only will basic material behavior with respect to safety issues in the divertor environment be examined, but innovative techniques for optimizing performance with respect to tritium safety by material modification and process control will be investigated. Supplementary experiments will be carried out at the Idaho National Engineering Laboratory and Sandia National Laboratory to expand and clarify results obtained on the Tritium Plasma Experiment.

Modeling and Analysis of Composite Wing Sections for Improved Aeroelastic and Vibration Characteristics Using Smart Materials

NASA Technical Reports Server (NTRS)

Chattopadhyay, Aditi

1996-01-01

The objective of this research is to develop analysis procedures to investigate the coupling of composite and smart materials to improve aeroelastic and vibratory response of aerospace structures. The structural modeling must account for arbitrarily thick geometries, embedded and surface bonded sensors and actuators and imperfections, such as delamination. Changes in the dynamic response due to the presence of smart materials and delaminations is investigated. Experiments are to be performed to validate the proposed mathematical model.

Forensic botany: usability of bryophyte material in forensic studies.

PubMed

Virtanen, Viivi; Korpelainen, Helena; Kostamo, Kirsi

2007-10-25

Two experiments were performed to test the relevance of bryophyte (Plantae, Bryophyta) material for forensic studies. The first experiment was conducted to reveal if, and how well, plant fragments attach to footwear in general. In the test, 16 persons walked outdoors wearing rubber boots or hiking boots. After 24h of use outdoors the boots were carefully cleaned, and all plant fragments were collected. Afterwards, all plant material was examined to identify the species. In the second experiment, fresh material of nine bryophyte species was kept in a shed in adverse conditions for 18 months, after which DNA was extracted and subjected to genotyping to test the quality of the material. Both experiments give support for the usability of bryophyte material in forensic studies. The bryophyte fragments become attached to shoes, where they remain even after the wearer walks on a dry road for several hours. Bryophyte DNA stays intact, allowing DNA profiling after lengthy periods following detachment from the original plant source. Based on these experiments, and considering the fact that many bryophytes are clonal plants, we propose that bryophytes are among the most usable plants to provide botanical evidence for forensic investigations.

Materials Science Experiment Module Accommodation within the Materials Science Research Rack (MSRR-1) on the International Space Station (ISS)

NASA Technical Reports Server (NTRS)

Higgins, D. B.; Jayroe, R. R.; McCarley, K. S.

2000-01-01

The Materials Science Research Rack I (MSRR-1) of the Materials Science Research Facility (MSRF) is a modular facility designed to accommodate two Experiment Modules (EM) simultaneously on board the International Space Station (ISS). One of these EMs will be the NASA/ESA EM being, developed collaboratively by NASA and the European Space Agency. The other EM position will be occupied by various multi-user EMs that will be exchanged in-orbit to accommodate a variety of materials science investigations. This paper discusses the resources, services, and allocations available to the EMs and briefly describes performance capabilities of the EMs currently planned for flight.

Pharmaceutical experiment aboard STS-67 mission

NASA Technical Reports Server (NTRS)

1995-01-01

Astronaut William G. Gregory, pilot, works with a pharmaceutical experiment on the middeck of the Earth-orbiting Space Shuttle Endeavour during the STS-67 mission. Commercial Materials Dispersion Apparatus Instruments Technology Associates Experiments (CMIX-03) includes not only pharmaceutical, but also biotechnology, cell biology, fluids, and crystal growth investigation

Astronaut William Gregory works with pharmaceutical experiments on middeck

NASA Technical Reports Server (NTRS)

1995-01-01

Astronaut William G. Gregory, STS-67 pilot, works with a pharmaceutical experiment on the middeck of the Earth-orbiting Space Shuttle Endeavour. Commercial Materials Dispersion Apparatus Instruments Technology Associates Experiments (CMIX-03) includes not only pharmaceutical but also biotechnology, cell biology, fluids and crystal growth investigations.

ASSESSMENT OF FUNGAL (PENICILLIUM CHRYSOGENUM) GROWTH ON THREE HVAC DUCT MATERIALS

EPA Science Inventory

The article discusses laboratory experiments to evaluate the susceptibility of three ventilation duct materials (fibrous glass ductboard, galvanized steel, and insulated flexible duct) to fungal (P. chrysogenum) growth. [NOTE: Many building investigators have documented fungal bi...

Pore Formation and Mobility Furnace within the MSG

NASA Technical Reports Server (NTRS)

2003-01-01

Dr. Richard Grugel, a materials scientist at NASA's Marshall Space Flight in Huntsville, Ala., examines the furnace used to conduct his Pore Formation and Mobility Investigation -- one of the first two materials science experiments to be conducted on the International Space Station. This experiment studies materials processes similar to those used to make components used in jet engines. Grugel's furnace was installed in the Microgravity Science Glovebox through the circular port on the side. In space, crewmembers are able to change out samples using the gloves on the front of the facility's work area.

The Chemistry of Shocked High-energy Materials: Connecting Atomistic Simulations to Experiments

NASA Astrophysics Data System (ADS)

Islam, Md Mahbubul; Strachan, Alejandro

2017-06-01

A comprehensive atomistic-level understanding of the physics and chemistry of shocked high energy (HE) materials is crucial for designing safe and efficient explosives. Advances in the ultrafast spectroscopy and laser shocks enabled the study of shock-induced chemistry at extreme conditions occurring at picosecond timescales. Despite this progress experiments are not without limitations and do not enable a direct characterization of chemical reactions. At the same time, large-scale reactive molecular dynamics (MD) simulations are capable of providing description of the shocked-induced chemistry but the uncertainties resulting from the use of approximate descriptions of atomistic interactions remain poorly quantified. We use ReaxFF MD simulations to investigate the shock and temperature induced chemical decomposition mechanisms of polyvinyl nitrate, RDX, and nitromethane. The effect of various shock pressures on reaction initiation mechanisms is investigated for all three materials. We performed spectral analysis from atomistic velocities at different shock pressures to enable direct comparison with experiments. The simulations predict volume-increasing reactions at the shock-to-detonation transitions and the shock vs. particle velocity data are in good agreement with available experimental data. The ReaxFF MD simulations validated against experiments enabled prediction of reaction kinetics of shocked materials, and interpretation of experimental spectroscopy data via assignment of the spectral peaks to dictate various reaction pathways at extreme conditions.

The Demonstration and Science Experiments (DSX) Mission

NASA Astrophysics Data System (ADS)

McCollough, J. P., II; Johnston, W. R.; Starks, M. J.; Albert, J.

2015-12-01

In 2016, the Air Force Research Laboratory will launch its Demonstration and Science Experiments mission to investigate wave-particle interactions and the particle and space environment in medium Earth orbit (MEO). The DSX spacecraft includes three experiment packages. The Wave Particle Interaction Experiment (WPIx) will perform active and passive investigations involving VLF waves and their interaction with plasma and energetic electrons in MEO. The Space Weather Experiment (SWx) includes five particle instruments to survey the MEO electron and proton environment. The Space Environmental Effects Experiment (SFx) will investigate effects of the MEO environment on electronics and materials. We will describe the capabilities of the DSX science payloads, science plans, and opportunities for collaborative studies such as conjunction observations and far-field measurements.

jsc2018m000297_Investigation_Seeks_to_Create_Self-Assembling_Materials-MP4

NASA Image and Video Library

2018-05-14

Investigation Seeks to Create Self-Assembling Materials------ As we travel farther into space, clever solutions to problems like engine part malfunctions and other possible mishaps will be a vital part of the planning process. 3D printing, or additive manufacturing, is an emerging technology that may be used to custom-create mission-critical parts. An integral piece of this process is understanding how particle shape, size distribution and packing behavior affect the manufacturing process. The Advanced Colloids Experiment-Temperature-7 investigation (ACE-T-7) aboard the International Space Station explores the feasibility of creating self-assembling microscopic particles for use in the manufacturing of materials during spaceflight. Read more about ACE-T-& here: https://www.nasa.gov/feature/investigation-seeks-to-create-self-assembling-materials

Tunable solid-state laser technology for applications to scientific and technological experiments from space

NASA Technical Reports Server (NTRS)

Allario, F.; Taylor, L. V.

1986-01-01

Current plans for the Earth Observing System (EOS) include development of a lidar facility to conduct scientific experiments from a polar orbiting platforms. A recommended set of experiments were scoped, which includes techniques of atmospheric backscatter (Lidar), Differential Absorption Lidar (DIAL), altimetry, and retroranging. Preliminary assessments of the resources (power, weight, volume) required by the Eos Lidar Facility were conducted. A research program in tunable solid state laser technology was developed, which includes laser materials development, modeling and experiments on the physics of solid state laser materials, and development of solid state laser transmitters with a strong focus on Eos scientific investigations. Some of the system studies that were conducted which highlight the payoff of solid state laser technology for the Eos scientific investigations will be discussed. Additionally, a summary of some promising research results which have recently emerged from the research program will be presented.

Deviatoric response of the aluminium alloy, 5083

NASA Astrophysics Data System (ADS)

Appleby-Thomas, Gareth; Hazell, Paul; Millett, Jeremy; Bourne, Neil

2009-06-01

Aluminium alloys such as 5083 are established light weight armour materials. As such, the shock response of these materials is of great importance. The shear strength of a material under shock loading provides an insight into its ballistic performance. In this investigation embedded manganin stress gauges have been employed to measure both the longitudinal and lateral components of stress during plate impact experiments over a range of impact stresses. In turn, these results were used to determine the shear strength and to investigate the time dependence of lateral stress behind the shock front to give an indication of material response.

Deviatoric Response of AN Armour-Grade Aluminium Alloy

NASA Astrophysics Data System (ADS)

Appleby-Thomas, G. J.; Hazell, P. J.; Millett, J.; Bourne, N. K.

2009-12-01

Aluminium alloys such as 5083 H32 are established light-weight armour materials. As such, the shock response of these materials is of great importance. The shear strength of a material under shock loading provides an insight into its ballistic performance. In this investigation embedded manganin stress gauges have been employed to measure both the longitudinal and lateral components of stress during plate-impact experiments over a range of impact stresses. In turn, these results were used to determine the shear strength and to investigate the time dependence of lateral stress behind the shock front to give an indication of material response.

Electrical and Chemical Experiments...from Edison.

ERIC Educational Resources Information Center

Schultz, Robert F.

Background information, lists of materials needed, and procedures are provided for 12 electrochemistry experiments. The experiments involve investigating: (1) a simple electrical circuit; (2) how a doorbell works; (3) how a two-way switch works; (4) conductors and insulators; (5) controlling current with a pencil; (6) what an electrolyte is; (7)…

Consort 1 sounding rocket flight

NASA Technical Reports Server (NTRS)

Wessling, Francis C.; Maybee, George W.

1989-01-01

This paper describes a payload of six experiments developed for a 7-min microgravity flight aboard a sounding rocket Consort 1, in order to investigate the effects of low gravity on certain material processes. The experiments in question were designed to test the effect of microgravity on the demixing of aqueous polymer two-phase systems, the electrodeposition process, the production of elastomer-modified epoxy resins, the foam formation process and the characteristics of foam, the material dispersion, and metal sintering. The apparatuses designed for these experiments are examined, and the rocket-payload integration and operations are discussed.

Materials Research Conducted Aboard the International Space Station: Facilities Overview, Operational Procedures, and Experimental Outcomes

NASA Technical Reports Server (NTRS)

Grugel, Richard N.; Luz, Paul; Smith, Guy; Spivey, Reggie; Jeter, Linda; Gillies, Donald; Hua, Fay; Anikumar, A. V.

2007-01-01

The Microgravity Science Glovebox (MSG) and Maintenance Work Area (MWA) are facilities aboard the International Space Station (ISS) that were used to successfully conduct experiments in support of, respectively, the Pore Formation and Mobility Investigation (PFMI) and the In-Space Soldering Investigation (ISSI). The capabilities of these facilities are briefly discussed and then demonstrated by presenting "real-time" and subsequently down-linked video-taped examples from the abovementioned experiments. Data interpretation, ISS telescience, some lessons learned, and the need of such facilities for conducting work in support of understanding materials behavior, particularly fluid processing and transport scenarios, in low-gravity environments is discussed.

Materials Research Conducted Aboard the International Space Station: Facilities Overview, Operational Procedures, and Experimental Outcomes

NASA Technical Reports Server (NTRS)

Grugel, R. N.; Luz, P.; Smith, G. A.; Spivey, R.; Jeter, L.; Gillies, D. C.; Hua, F.; Anilkumar, A. V.

2006-01-01

The Microgravity Science Glovebox (MSG) and Maintenance Work Area (MWA) are facilities aboard the International Space Station (ISS) that were used to successfully conduct experiments in support of, respectively, the Pore Formation and Mobility Investigation (PFMI) and the In-Space Soldering Investigation (ISSI). The capabilities of these facilities are briefly discussed and then demonstrated by presenting real-time and subsequently down-linked video-taped examples from the abovementioned experiments. Data interpretation, ISS telescience, some lessons learned, and the need of such facilities for conducting work in support of understanding materials behavior, particularly fluid processing and transport scenarios, in low-gravity environments is discussed.

Investigating the effect of multiple layers of insulation with a bubble wrap experiment

NASA Astrophysics Data System (ADS)

Eggers, Dolores; Ruiz, Michael J.

2018-03-01

We provide a fun, inexpensive laboratory experiment for students to investigate the effects of multiple layers of insulation and observe diminishing values for additional layers using bubble wrap. This experiment provides an opportunity for students to learn about heat transfer through conduction using readily available materials. A water-ice pack is placed on top of five layers of bubble wrap. The temperature is taken between each layer periodically for at least 15 min. Students determine asymptotic temperatures for varying layers. This experiment also suggests a real world application.

Experimental Investigation Nano Particles Influence in NPMEDM to Machine Inconel 800 with Electrolyte Copper Electrode

NASA Astrophysics Data System (ADS)

Karunakaran, K.; Chandrasekaran, M.

2017-05-01

The recent technology of machining hard materials is Powder mix dielectric electrical Discharge Machining (PMEDM). This research investigates nano sized (about 5Nm) powders influence in machining Inconel 800 nickel based super alloy. This work is motivated for a practical need for a manufacturing industry, which processes various kinds of jobs of Inconel 800 material. The conventional EDM machining also considered for investigation for the measure of Nano powders performances. The aluminum, silicon and multi walled Carbon Nano tubes powders were considered in this investigation along with pulse on time, pulse of time and input current to analyze and optimize the responses of Material Removal Rate, Tool Wear Rate and surface roughness. The Taguchi general Full Factorial Design was used to design the experiments. The most advance equipments employed in conducting experiments and measuring equipments to improve the accuracy of the result. The MWCNT powder mix was out performs than other powders which reduce 22% to 50% of the tool wear rate, gives the surface roughness reduction from 29.62% to 41.64% and improved MRR 42.91% to 53.51% than conventional EDM.

Use of simulated experiments for material characterization of brittle materials subjected to high strain rate dynamic tension

PubMed Central

Saletti, Dominique

2017-01-01

Rapid progress in ultra-high-speed imaging has allowed material properties to be studied at high strain rates by applying full-field measurements and inverse identification methods. Nevertheless, the sensitivity of these techniques still requires a better understanding, since various extrinsic factors present during an actual experiment make it difficult to separate different sources of errors that can significantly affect the quality of the identified results. This study presents a methodology using simulated experiments to investigate the accuracy of the so-called spalling technique (used to study tensile properties of concrete subjected to high strain rates) by numerically simulating the entire identification process. The experimental technique uses the virtual fields method and the grid method. The methodology consists of reproducing the recording process of an ultra-high-speed camera by generating sequences of synthetically deformed images of a sample surface, which are then analysed using the standard tools. The investigation of the uncertainty of the identified parameters, such as Young's modulus along with the stress–strain constitutive response, is addressed by introducing the most significant user-dependent parameters (i.e. acquisition speed, camera dynamic range, grid sampling, blurring), proving that the used technique can be an effective tool for error investigation. This article is part of the themed issue ‘Experimental testing and modelling of brittle materials at high strain rates’. PMID:27956505

Materials Science Research Hardware for Application on the International Space Station: an Overview of Typical Hardware Requirements and Features

NASA Technical Reports Server (NTRS)

Schaefer, D. A.; Cobb, S.; Fiske, M. R.; Srinivas, R.

2000-01-01

NASA's Marshall Space Flight Center (MSFC) is the lead center for Materials Science Microgravity Research. The Materials Science Research Facility (MSRF) is a key development effort underway at MSFC. The MSRF will be the primary facility for microgravity materials science research on board the International Space Station (ISS) and will implement the NASA Materials Science Microgravity Research Program. It will operate in the U.S. Laboratory Module and support U. S. Microgravity Materials Science Investigations. This facility is being designed to maintain the momentum of the U.S. role in microgravity materials science and support NASA's Human Exploration and Development of Space (HEDS) Enterprise goals and objectives for Materials Science. The MSRF as currently envisioned will consist of three Materials Science Research Racks (MSRR), which will be deployed to the International Space Station (ISS) in phases, Each rack is being designed to accommodate various Experiment Modules, which comprise processing facilities for peer selected Materials Science experiments. Phased deployment will enable early opportunities for the U.S. and International Partners, and support the timely incorporation of technology updates to the Experiment Modules and sensor devices.

Long Duration Exposure Facility (LDEF) preliminary findings: LEO space effects on the space plasma-voltage drainage experiment

NASA Technical Reports Server (NTRS)

Blakkolb, Brian K.; Yaung, James Y.; Henderson, Kelly A.; Taylor, William W.; Ryan, Lorraine E.

1992-01-01

The Space Plasma-High Voltage Drainage Experiment (SP-HVDE) provided a unique opportunity to study long term space environmental effects on materials because it was comprised of two identical experimental trays; one tray located on the ram facing side (D-10), and the other on the wake facing side (B-4) of the LDEF. This configuration allows for the comparison of identical materials exposed to two distinctly different environments. The purpose of this work is to document an assessment of the effects of five and three quarters years of low Earth orbital space exposure on materials comprising the SP-HVDE (experiment no. A0054). The findings of the materials investigation reported focus on atomic oxygen effects, micrometeor and debris impact site documentation, thermal property measurements, and environmentally induced contamination.

Results of the "Komplast" experiment on the long-term exposure of materials specimens on the ISS surface

NASA Astrophysics Data System (ADS)

Shumov, Andrey; Novikov, Lev

The "Komplast" materials experiment was designed by the Khrunichev State Research and Production Space Center together with Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University and other Russian scientific institutes, and has been carried out since 1998. The aim of the experiment is to study the complex effects of space factors on specimens of various materials. Eight “Komplast” panels fitted with material specimens equipped UV-sensors and temperature sensors were located on the International Space Station (ISS) Functional Cargo Block (FGB) module exterior surface. The panels were sent into orbit with the FGB when it launched on November 20, 1998. Two of these panels were subsequently returned to Earth by Space Shuttle Discovery after 12 years of LEO exposure. The uniqueness of the "Komplast" experiment determined by long duration of open space exposure, which is much longer than in other similar experiments. For example LDEF: 1984-1990, HEEI (Space Station "Mir"): 1996-1997, MISSE-1, -2 (ISS): 1,5-2 years. In this work reveals laboratory research results of some materials specimens, which had been exposed on “Komplast” panels. A distinctive feature of this research was additional irradiation of specimens by atomic oxygen and electrons with energies of ~ 1-8 MeV in laboratory. In the interpretation of the experiment results was taken into account the specimens exposure temperature conditions on the ISS exterior surface and the conditions of their sunlit, defined by the above-mentioned sensors readings. Lot of attention was paid to the investigation of rubber materials specimens. The deformation, mechanical and relaxation characteristics were defined for the specimens. Also were investigations the seals-ability of model rubber seals after the long-term outer exposure. It was determined conservation volumetric deformation and relaxation characteristics of the exposed specimens and the localization of structural changes in the thin surface layer of the exposed materials on surfaces in direct contact with the open space. Was investigated the elemental and molecular composition of the panel surface contaminations, which were caused by evaporation of components of the specimens of rubber materials. The data on the change in the strength of adhesive joints of different pairs of materials during their long-term operation in the space environment was obtained. Characteristics of the exposed specimens were compared with the control specimens, which were kept in laboratory conditions. According to the research of carbon plastic specimens with epoxy resin obtained experimental data on the stability of the macro and micro structure of carbon plastic, as well as a change in the strength characteristics after exposure. We obtain estimates of the influence of space factors on the carbon plastics structure and properties. By optical and electron microscopy were investigated craters on the surface of polished metal specimens and panels created by micrometeoroids and space debris impacts, as well as low-speed particles bonded to the surface. The elemental composition of substance in the craters and low-speed particles was determined, which enables to identify the origin of particles. The results obtained in the "Komplast" experiment allow giving a forecast changes in the properties of materials at their long-term operation in the ISS orbit. Are currently under exposure the remaining six panels "Komplast" on the surface of the FGB. Return and their detailed studying is considered in plans for further work.

The NASA Materials Science Research Program: It's New Strategic Goals and Opportunities

NASA Technical Reports Server (NTRS)

Schlagheck, Ronald A.; Stagg, Elizabeth

2004-01-01

In the past year, the NASA s Office of Biological and Physical Research (OBPR) has formulated a long term plan to perform strategical and fundamental research bringing together physics, chemistry, biology, and engineering to solve problems needed for current and future agency mission goals. Materials Science is one of basic disciplines within the Enterprise s Division of Physical Sciences Research. The Materials Science Program participates to utilize effective use of International Space Station (ISS) and various world class ground laboratory facilities to solve new scientific and technology questions and transfer these results for public and agency benefits. The program has recently targeted new investigative research in strategic areas necessary to expand NASA knowledge base for exploration of the universe and some of these experiments will need access to the microgravity of space. The program is implementing a wide variety of traditional ground and flight based research related types of fundamental science related to materials crystallization, fundamental processing, and properties characterization in order to obtain basic understanding of various phenomena effects and relationships to the structures, processing, and properties of materials. , In addition new initiatives in radiation protection, materials for propulsion and In-space fabrication and repair focus on research helping the agency solve problems needed for future transportation into the solar system. A summary of the types and sources for this research is presented including those experiments planned for a low gravity environment. Areas to help expand the science basis for NASA future missions are described. An overview of the program is given including the scope of the current and future NASA Research Announcements with emphasis on new materials science initiatives. A description of the planned flight experiments to be conducted on the International Space Station program along with the planned facility class Materials Science Research Rack (MSRR) and Microgravity Glovebox (MSG) type investigations. Some initial results from the first three materials experiments are given.

Deontic Reasoning with Emotional Content: Evolutionary Psychology or Decision Theory?

ERIC Educational Resources Information Center

Perham, Nick; Oaksford, Mike

2005-01-01

Three experiments investigated the contrasting predictions of the evolutionary and decision-theoretic approaches to deontic reasoning. Two experiments embedded a hazard management (HM) rule in a social contract scenario that should lead to competition between innate modules. A 3rd experiment used a pure HM task. Threatening material was also…

Context, Contrast, and Tone of Voice in Auditory Sarcasm Perception

ERIC Educational Resources Information Center

Voyer, Daniel; Thibodeau, Sophie-Hélène; Delong, Breanna J.

2016-01-01

Four experiments were conducted to investigate the interplay between context and tone of voice in the perception of sarcasm. These experiments emphasized the role of contrast effects in sarcasm perception exclusively by means of auditory stimuli whereas most past research has relied on written material. In all experiments, a positive or negative…

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.

On the hitchhiker Robot Operated Materials Processing System: Experiment data system

NASA Technical Reports Server (NTRS)

Kizhner, Semion; Jenstrom, Del

1995-01-01

The Space Shuttle Discovery STS-64 mission carried the first American autonomous robot into space, the Robot Operated Materials Processing System (ROMPS). On this mission ROMPS was the only Hitchhiker experiment and had a unique opportunity to utilize all Hitchhiker space carrier capabilities. ROMPS conducted rapid thermal processing of the one hundred semiconductor material samples to study how micro gravity affects the resulting material properties. The experiment was designed, built and operated by a small GSFC team in cooperation with industry and university based principal investigators who provided the material samples and data interpretation. ROMPS' success presents some valuable lessons in such cooperation, as well as in the utilization of the Hitchhiker carrier for complex applications. The motivation of this paper is to share these lessons with the scientific community interested in attached payload experiments. ROMPS has a versatile and intelligent material processing control data system. This paper uses the ROMPS data system as the guiding thread to present the ROMPS mission experience. It presents an overview of the ROMPS experiment followed by considerations of the flight and ground data subsystems and their architecture, data products generation during mission operations, and post mission data utilization. It then presents the lessons learned from the development and operation of the ROMPS data system as well as those learned during post-flight data processing.

Design Features and Capabilities of the First Materials Science Research Rack

NASA Technical Reports Server (NTRS)

Pettigrew, P. J.; Lehoczky, S. L.; Cobb, S. D.; Holloway, T.; Kitchens, L.

2003-01-01

The First Materials Science Research Rack (MSRR-1) aboard the International Space Station (ISS) will offer many unique capabilities and design features to facilitate a wide range of materials science investigations. The initial configuration of MSRR-1 will accommodate two independent Experiment Modules (EMS) and provide the capability for simultaneous on-orbit processing. The facility will provide the common subsystems and interfaces required for the operation of experiment hardware and accommodate telescience capabilities. MSRR1 will utilize an International Standard Payload Rack (ISPR) equipped with an Active Rack Isolation System (ARIS) for vibration isolation of the facility.

Pore Formation and Mobility Investigation (PFMI): Concept, Hardware Development, and Initial Analysis of Experiments Conducted Aboard the International Space Station

NASA Technical Reports Server (NTRS)

Grugel, Richard N.

2003-01-01

Porosity in the form of "bubbles and pipes" can occur during controlled directional solidification processing of metal alloys. This is a consequence that 1) precludes obtaining any meaningful scientific results and 2) is detrimental to desired material properties. Unfortunately, several Microgravity experiments have been compromised by porosity. The intent of the PFMl investigation is to conduct a systematic effort directed towards understanding porosity formation and mobility during controlled directional solidification (DS) in a microgravity environment. PFMl uses a pure transparent material, succinonitrile (SCN), as well as SCN "alloyed" with water, in conjunction with a translating temperature gradient stage so that direct observation and recording of pore generation and mobility can be made. PFMl is investigating the role of thermocapillary forces and temperature gradients in affecting bubble dynamics as well as other solidification processes in a microgravity environment. This presentation will cover the concept, hardware development, operations, and the initial results from experiments conducted aboard the International Space Station.

Pore Formation and Mobility Investigation (PFMI): Concept, Hardware Development and Initial Analysis of Experiments

NASA Technical Reports Server (NTRS)

Grugel, Richard N.

2004-01-01

Porosity in the form of "bubbles and pipes" can occur during controlled directional solidification processing of metal alloys. This is a consequence that 1) precludes obtaining any meaningful scientific results and 2) is detrimental to desired material properties. Unfortunately, several Microgravity experiments have been compromised by porosity. The intent of the PFMI investigation is to conduct a systematic effort directed towards understanding porosity formation and mobility during controlled directional solidification (DS) in a microgravity environment. PFMI uses a pure transparent material, succinonitrile (SCN), as well as SCN "alloyed" with water, in conjunction with a translating temperature gradient stage so that direct observation and recording of pore generation and mobility can be made. PFMI is investigating the role of thermocapillary forces and temperature gradients in affecting bubble dynamics as well as other solidification processes in a microgravity Environment. This presentation will cover the concept, hardware development, operations, and the initial results from experiments conducted aboard the International Space Station. .

Materials processing in space, 1980 science planning document. [crystal growth, containerless processing, solidification, bioprocessing, and ultrahigh vacuum processes

NASA Technical Reports Server (NTRS)

Naumann, R. J.

1980-01-01

The scientific aspects of the Materials Processing in Space program are described with emphasis on the major categories of interest: (1) crystal growth; (2) solidification of metals, alloys, and composites; (3) fluids and chemical processes; (4) containerless processing, glasses, and refractories; (5) ultrahigh vacuum processes; and (6) bioprocessing. An index is provided for each of these areas. The possible contributions that materials science experiments in space can make to the various disciplines are summarized, and the necessity for performing experiments in space is justified. What has been learned from previous experiments relating to space processing, current investigations, and remaining issues that require resolution are discussed. Recommendations for the future direction of the program are included.

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.

Modeling rock specimens through 3D printing: Tentative experiments and prospects

NASA Astrophysics Data System (ADS)

Jiang, Quan; Feng, Xiating; Song, Lvbo; Gong, Yahua; Zheng, Hong; Cui, Jie

2016-02-01

Current developments in 3D printing (3DP) technology provide the opportunity to produce rock-like specimens and geotechnical models through additive manufacturing, that is, from a file viewed with a computer to a real object. This study investigated the serviceability of 3DP products as substitutes for rock specimens and rock-type materials in experimental analysis of deformation and failure in the laboratory. These experiments were performed on two types of materials as follows: (1) compressive experiments on printed sand-powder specimens in different shapes and structures, including intact cylinders, cylinders with small holes, and cuboids with pre-existing cracks, and (2) compressive and shearing experiments on printed polylactic acid cylinders and molded shearing blocks. These tentative tests for 3DP technology have exposed its advantages in producing complicated specimens with special external forms and internal structures, the mechanical similarity of its product to rock-type material in terms of deformation and failure, and its precision in mapping shapes from the original body to the trial sample (such as a natural rock joint). These experiments and analyses also successfully demonstrate the potential and prospects of 3DP technology to assist in the deformation and failure analysis of rock-type materials, as well as in the simulation of similar material modeling experiments.

The Komplast Experiment: Space Environmental Effects after 12 Years in LEO (and Counting)

NASA Technical Reports Server (NTRS)

Shaevich, Sergei K.; Aleksandrov, Nicholai G.; Shumov, Andrei E.; Novikov, L. S.; Alred, John A.; Shindo, David J.; Kravchenko, Michael; Golden, Johnny L.

2014-01-01

The Komplast materials experiment was designed by the Khrunichev Space Center, together with other Russian scientific institutes, and has been carried out by Mission Control Moscow since 1998. The purpose is to study the effect of the low earth orbit (LEO) environment on exposed samples of various spacecraft materials. The Komplast experiment began with the launch of the first International Space Station (ISS) module on November 20, 1998. Two of eight experiment panels were retrieved during Russian extravehicular activity in February 2011 after 12 years of LEO exposure, and were subsequently returned to Earth by Space Shuttle "Discovery" on the STS-133/ULF-5 mission. The retrieved panels contained an experiment to detect micrometeoroid and orbital debris (MMOD) impacts, radiation sensors, a temperature sensor, several pieces of electrical cable, both carbon composite and adhesive-bonded samples, and many samples made from elastomeric and fluoroplastic materials. Our investigation is complete and a summary of the results obtained from this uniquely long-duration exposure experiment will be presented.

Space processing of composite materials

NASA Technical Reports Server (NTRS)

Steurer, W. H.; Kaye, S.

1975-01-01

Materials and processes for the testing of aluminum-base fiber and particle composites, and of metal foams under extended-time low-g conditions were investigated. A wetting and dispersion technique was developed, based on the theory that under the absence of a gas phase all solids are wetted by liquids. The process is characterized by a high vacuum environment and a high temperature cycle. Successful wetting and dispersion experiments were carried out with sapphire fibers, whiskers and particles, and with fibers of silicon carbide, pyrolytic graphite and tungsten. The developed process and facilities permit the preparation of a precomposite which serves as sample material for flight experiments. Low-g processing consists then merely in the uniform redistribution of the reinforcements during a melting cycle. For the preparation of metal foams, gas generation by means of a thermally decomposing compound was found most adaptable to flight experiments. For flight experiments, the use of compacted mixture of the component materials limits low-g processing to a simple melt cycle.

Investigating Effects of Fused-Deposition Modeling (FDM) Processing Parameters on Flexural Properties of ULTEM 9085 using Designed Experiment.

PubMed

Gebisa, Aboma Wagari; Lemu, Hirpa G

2018-03-27

Fused-deposition modeling (FDM), one of the additive manufacturing (AM) technologies, is an advanced digital manufacturing technique that produces parts by heating, extruding and depositing filaments of thermoplastic polymers. The properties of FDM-produced parts apparently depend on the processing parameters. These processing parameters have conflicting advantages that need to be investigated. This article focuses on an investigation into the effect of these parameters on the flexural properties of FDM-produced parts. The investigation is carried out on high-performance ULTEM 9085 material, as this material is relatively new and has potential application in the aerospace, military and automotive industries. Five parameters: air gap, raster width, raster angle, contour number, and contour width, with a full factorial design of the experiment, are considered for the investigation. From the investigation, it is revealed that raster angle and raster width have the greatest effect on the flexural properties of the material. The optimal levels of the process parameters achieved are: air gap of 0.000 mm, raster width of 0.7814 mm, raster angle of 0°, contour number of 5, and contour width of 0.7814 mm, leading to a flexural strength of 127 MPa, a flexural modulus of 2400 MPa, and 0.081 flexural strain.

Investigating Effects of Fused-Deposition Modeling (FDM) Processing Parameters on Flexural Properties of ULTEM 9085 using Designed Experiment

PubMed Central

Gebisa, Aboma Wagari

2018-01-01

Fused-deposition modeling (FDM), one of the additive manufacturing (AM) technologies, is an advanced digital manufacturing technique that produces parts by heating, extruding and depositing filaments of thermoplastic polymers. The properties of FDM-produced parts apparently depend on the processing parameters. These processing parameters have conflicting advantages that need to be investigated. This article focuses on an investigation into the effect of these parameters on the flexural properties of FDM-produced parts. The investigation is carried out on high-performance ULTEM 9085 material, as this material is relatively new and has potential application in the aerospace, military and automotive industries. Five parameters: air gap, raster width, raster angle, contour number, and contour width, with a full factorial design of the experiment, are considered for the investigation. From the investigation, it is revealed that raster angle and raster width have the greatest effect on the flexural properties of the material. The optimal levels of the process parameters achieved are: air gap of 0.000 mm, raster width of 0.7814 mm, raster angle of 0°, contour number of 5, and contour width of 0.7814 mm, leading to a flexural strength of 127 MPa, a flexural modulus of 2400 MPa, and 0.081 flexural strain. PMID:29584674

Physical cognition: birds learn the structural efficacy of nest material

PubMed Central

Bailey, Ida E.; Morgan, Kate V.; Bertin, Marion; Meddle, Simone L.; Healy, Susan D.

2014-01-01

It is generally assumed that birds’ choice of structurally suitable materials for nest building is genetically predetermined. Here, we tested that assumption by investigating whether experience affected male zebra finches’ (Taeniopygia guttata) choice of nest material. After a short period of building with relatively flexible string, birds preferred to build with stiffer string while those that had experienced a stiffer string were indifferent to string type. After building a complete nest with either string type, however, all birds increased their preference for stiff string. The stiffer string appeared to be the more effective building material as birds required fewer pieces of stiffer than flexible string to build a roofed nest. For birds that raised chicks successfully, there was no association between the material they used to build their nest and the type they subsequently preferred. Birds’ material preference reflected neither the preference of their father nor of their siblings but juvenile experience of either string type increased their preference for stiffer string. Our results represent two important advances: (i) birds choose nest material based on the structural properties of the material; (ii) nest material preference is not entirely genetically predetermined as both the type and amount of experience influences birds’ choices. PMID:24741011

Physical cognition: birds learn the structural efficacy of nest material.

PubMed

Bailey, Ida E; Morgan, Kate V; Bertin, Marion; Meddle, Simone L; Healy, Susan D

2014-06-07

It is generally assumed that birds' choice of structurally suitable materials for nest building is genetically predetermined. Here, we tested that assumption by investigating whether experience affected male zebra finches' (Taeniopygia guttata) choice of nest material. After a short period of building with relatively flexible string, birds preferred to build with stiffer string while those that had experienced a stiffer string were indifferent to string type. After building a complete nest with either string type, however, all birds increased their preference for stiff string. The stiffer string appeared to be the more effective building material as birds required fewer pieces of stiffer than flexible string to build a roofed nest. For birds that raised chicks successfully, there was no association between the material they used to build their nest and the type they subsequently preferred. Birds' material preference reflected neither the preference of their father nor of their siblings but juvenile experience of either string type increased their preference for stiffer string. Our results represent two important advances: (i) birds choose nest material based on the structural properties of the material; (ii) nest material preference is not entirely genetically predetermined as both the type and amount of experience influences birds' choices.

Microgravity

NASA Image and Video Library

2000-04-14

Representatives of NASA materials science experiments supported the NASA exhibit at the Rernselaer Polytechnic Institute's Space Week activities, April 5 through 11, 1999. From left to right are: Angie Jackman, project manager at NASA's Marshall Space Flight Center for dendritic growth experiments; Dr. Martin Glicksman of Rennselaer Polytechnic Instutute, Troy, NY, principal investigator on the Isothermal Dendritic Growth Experiment (IDGE) that flew three times on the Space Shuttle; and Dr. Matthew Koss of College of the Holy Cross in Worcester, MA, a co-investigator on the IDGE and now principal investigator on the Transient Dendritic Solidification Experiment being developed for the International Space Station (ISS). The image at far left is a dendrite grown in Glicksman's IDGE tests aboard the Shuttle. Glicksman is also principal investigator for the Evolution of Local Microstructures: Spatial Instabilities of Coarsening Clusters.

Microgravity

NASA Image and Video Library

2004-04-15

Computed tomography (CT) images of resin-impregnated Mechanics of Granular Materials (MGM) specimens are assembled to provide 3-D volume renderings of density patterns formed by dislocation under the external loading stress profile applied during the experiments. Experiments flown on STS-79 and STS-89. Principal Investigator: Dr. Stein Sture

In search of the emotional face: anger versus happiness superiority in visual search.

PubMed

Savage, Ruth A; Lipp, Ottmar V; Craig, Belinda M; Becker, Stefanie I; Horstmann, Gernot

2013-08-01

Previous research has provided inconsistent results regarding visual search for emotional faces, yielding evidence for either anger superiority (i.e., more efficient search for angry faces) or happiness superiority effects (i.e., more efficient search for happy faces), suggesting that these results do not reflect on emotional expression, but on emotion (un-)related low-level perceptual features. The present study investigated possible factors mediating anger/happiness superiority effects; specifically search strategy (fixed vs. variable target search; Experiment 1), stimulus choice (Nimstim database vs. Ekman & Friesen database; Experiments 1 and 2), and emotional intensity (Experiment 3 and 3a). Angry faces were found faster than happy faces regardless of search strategy using faces from the Nimstim database (Experiment 1). By contrast, a happiness superiority effect was evident in Experiment 2 when using faces from the Ekman and Friesen database. Experiment 3 employed angry, happy, and exuberant expressions (Nimstim database) and yielded anger and happiness superiority effects, respectively, highlighting the importance of the choice of stimulus materials. Ratings of the stimulus materials collected in Experiment 3a indicate that differences in perceived emotional intensity, pleasantness, or arousal do not account for differences in search efficiency. Across three studies, the current investigation indicates that prior reports of anger or happiness superiority effects in visual search are likely to reflect on low-level visual features associated with the stimulus materials used, rather than on emotion. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Experiments to ensure Space Station fire safety - A challenge

NASA Technical Reports Server (NTRS)

Youngblood, W. W.; Seiser, K. M.

1988-01-01

Three experiments have been formulated in order to address prominent fire safety requirements aboard the NASA Space Shuttle; these experiments are to be conducted as part of a Space Station-based Technology Development Mission for the growth phase of Space Station construction and operation. The experiments are: (1) an investigation of the flame-spread rate and combustion-product evolution in the burning of typical spacecraft materials in low gravity; (2) an evaluation of the interaction of fires and candidate fire extinguishers in low gravity; and (3) an investigation of the persistence and propagation of smoldering and deep-seated combustion in low gravity.

Investigating Nanoscopic Structures on a Butterfly Wing to Explore Solvation and Coloration

ERIC Educational Resources Information Center

Bober, Brittany A.; Ogata, Jennifer K.; Martinez, Veronica E.; Hallinan, Janae J.; Leach, Taylor A.; Negru, Bogdan

2018-01-01

Surface structures on the nanometer size scale can impart new and exciting properties to bulk materials. Nanoscopic structures on hydrophobic materials can result in superhydrophobicity and structural coloration. We present an interdisciplinary experiment that introduces undergraduate students to nanotechnology by manipulating the…

Microgravity

NASA Image and Video Library

1998-09-30

The Electrostatic Levitator (ESL) Facility established at Marshall Space Flight Center (MSFC) supports NASA's Microgravity Materials Science Research Program. NASA materials science investigations include ground-based, flight definition and flight projects. Flight definition projects, with demanding science concept review schedules, receive highest priority for scheduling experiment time in the Electrostatic Levitator (ESL) Facility.

A comparison of haptic material perception in blind and sighted individuals.

PubMed

Baumgartner, Elisabeth; Wiebel, Christiane B; Gegenfurtner, Karl R

2015-10-01

We investigated material perception in blind participants to explore the influence of visual experience on material representations and the relationship between visual and haptic material perception. In a previous study with sighted participants, we had found participants' visual and haptic judgments of material properties to be very similar (Baumgartner, Wiebel, & Gegenfurtner, 2013). In a categorization task, however, visual exploration had led to higher categorization accuracy than haptic exploration. Here, we asked congenitally blind participants to explore different materials haptically and rate several material properties in order to assess the role of the visual sense for the emergence of haptic material perception. Principal components analyses combined with a procrustes superimposition showed that the material representations of blind and blindfolded sighted participants were highly similar. We also measured haptic categorization performance, which was equal for the two groups. We conclude that haptic material representations can emerge independently of visual experience, and that there are no advantages for either group of observers in haptic categorization. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dual-Materials Dispersion Apparatus

NASA Technical Reports Server (NTRS)

2003-01-01

Experiments to seek solutions for a range of biomedical issues are at the heart of several investigations that will be hosted by the Commercial Instrumentation Technology Associates (ITA), Inc. Biomedical Experiments (CIBX-2) payload. CIBX-2 is unique, encompassing more than 20 separate experiments including cancer research, commercial experiments, and student hands-on experiments from 10 schools as part of ITA's ongoing University Among the Stars program. This drawing depicts a cross-section of a set of Dual-Materials Dispersion Apparatus (DMDA) specimen wells, one of which can include a reverse osmosis membrane to dewater a protein solution and thus cause crystallization. Depending on individual needs, two or three wells may be used, the membrane may be absent, or other proprietary enhancements may be present. The experiments are sponsored by NASA's Space Product Development Program (SPD).

Waiting for Merlot: anticipatory consumption of experiential and material purchases.

PubMed

Kumar, Amit; Killingsworth, Matthew A; Gilovich, Thomas

2014-10-01

Experiential purchases (money spent on doing) tend to provide more enduring happiness than material purchases (money spent on having). Although most research comparing these two types of purchases has focused on their downstream hedonic consequences, the present research investigated hedonic differences that occur before consumption. We argue that waiting for experiences tends to be more positive than waiting for possessions. Four studies demonstrate that people derive more happiness from the anticipation of experiential purchases and that waiting for an experience tends to be more pleasurable and exciting than waiting to receive a material good. We found these effects in studies using questionnaires involving a variety of actual planned purchases, in a large-scale experience-sampling study, and in an archival analysis of news stories about people waiting in line to make a purchase. Consumers derive value from anticipation, and that value tends to be greater for experiential than for material purchases. © The Author(s) 2014.

KSC-97PC952

NASA Image and Video Library

1997-07-01

STS-94 Mission Specialist Donald A. Thomas smiles as a suit technician helps him into his launch/entry suit in the Operations and Checkout (O&C) Building. He has flown on STS-83, STS-70 and STS-65. He holds a doctorate in materials science and has been the Principal Investigator for a Space Shuttle crystal growth experiment. Because of his background in materials science, Thomas will be concentrating his efforts during the Red shift on the five experiments in this discipline in the Large Isothermal Furnace. He also will work on the ten materials science investigations in the Electromagnetic Containerless Processing Facility and four that will be measuring the effects of microgravity and motion in the orbiter on the experiments. Thomas and six fellow crew members will shortly depart the O&C and head for Launch Pad 39A, where the Space Shuttle Columbia will lift off during a launch window that opens at 1:50 p.m. EDT, July 1. The launch window was opened 47 minutes early to improve the opportunity to lift off before Florida summer rain showers reached the space center

Is It "Writing on Water" or "Strike It Rich?" The Experiences of Prospective Teachers in Using Search Engines

ERIC Educational Resources Information Center

Sahin, Abdurrahman; Cermik, Hulya; Dogan, Birsen

2010-01-01

Information searching skills have become increasingly important for prospective teachers with the exponential growth of learning materials on the web. This study is an attempt to understand the experiences of prospective teachers with search engines through metaphoric images and to further investigate whether their experiences are related to the…

Some "Thing" to Talk About? Differential Story Utility From Experiential and Material Purchases.

PubMed

Kumar, Amit; Gilovich, Thomas

2015-10-01

Psychological research has shown that experiential purchases (a hike in the woods, a trip to Rome) bring more happiness than material purchases (a designer shirt, a flat-screen television). The research presented in this article investigates one cause and consequence of this difference: People talk more about their experiences than their possessions and derive more value from doing so. A series of eight studies demonstrate that taking away the ability to talk about experiences (but not material goods) would diminish the enjoyment they bring; that people believe they derive more happiness from talking about experiential purchases; that when given a choice about which of their purchases to talk about, people are more likely to talk about experiential rather than material consumption; and that people report being more inclined to talk about their experiences than their material purchases and derive more hedonic benefits as a result--both in prospect and in retrospect. © 2015 by the Society for Personality and Social Psychology, Inc.

Learning to perceive haptic distance-to-break in the presence of friction.

PubMed

Altenhoff, Bliss M; Pagano, Christopher C; Kil, Irfan; Burg, Timothy C

2017-02-01

Two experiments employed attunement and calibration training to investigate whether observers are able to identify material break points in compliant materials through haptic force application. The task required participants to attune to a recently identified haptic invariant, distance-to-break (DTB), rather than haptic stimulation not related to the invariant, including friction. In the first experiment participants probed simulated force-displacement relationships (materials) under 3 levels of friction with the aim of pushing as far as possible into the materials without breaking them. In a second experiment a different set of participants pulled on the materials. Results revealed that participants are sensitive to DTB for both pushing and pulling, even in the presence of varying levels of friction, and this sensitivity can be improved through training. The results suggest that the simultaneous presence of friction may assist participants in perceiving DTB. Potential applications include the development of haptic training programs for minimally invasive (laparoscopic) surgery to reduce accidental tissue damage. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Thermostructural characterization and structural elastic property optimization of novel high luminosity LHC collimation materials at CERN

NASA Astrophysics Data System (ADS)

Borg, M.; Bertarelli, A.; Carra, F.; Gradassi, P.; Guardia-Valenzuela, J.; Guinchard, M.; Izquierdo, G. Arnau; Mollicone, P.; Sacristan-de-Frutos, O.; Sammut, N.

2018-03-01

The CERN Large Hadron Collider is currently being upgraded to operate at a stored beam energy of 680 MJ through the High Luminosity upgrade. The LHC performance is dependent on the functionality of beam collimation systems, essential for safe beam cleaning and machine protection. A dedicated beam experiment at the CERN High Radiation to Materials facility is created under the HRMT-23 experimental campaign. This experiment investigates the behavior of three collimation jaws having novel composite absorbers made of copper diamond, molybdenum carbide graphite, and carbon fiber carbon, experiencing accidental scenarios involving the direct beam impact on the material. Material characterization is imperative for the design, execution, and analysis of such experiments. This paper presents new data and analysis of the thermostructural characteristics of some of the absorber materials commissioned within CERN facilities. In turn, characterized elastic properties are optimized through the development and implementation of a mixed numerical-experimental optimization technique.

NASA/First Materials Science Research Rack (MSRR-1) Module Inserts Development for the International Space Station

NASA Technical Reports Server (NTRS)

Crouch, Myscha; Carswell, Bill; Farmer, Jeff; Rose, Fred; Tidwell, Paul

1999-01-01

The Material Science Research Rack 1 (MSRR-1) of the Material Science Research Facility (MSRF) contains an Experiment Module (EM) being developed collaboratively by NASA and the European Space Agency (ESA). This NASA/ESA EM will accommodate several different removable and replaceable Module Inserts (MIs) which are installed on orbit. Two of the NASA MIs being developed for specific material science investigations are described herein.

New Technologies Being Developed for the Thermophoretic Sampling of Smoke Particulates in Microgravity

NASA Technical Reports Server (NTRS)

Sheredy, William A.

2003-01-01

The Characterization of Smoke Particulate for Spacecraft Fire Detection, or Smoke, microgravity experiment is planned to be performed in the Microgravity Science Glovebox Facility on the International Space Station (ISS). This investigation, which is being developed by the NASA Glenn Research Center, ZIN Technologies, and the National Institute of Standards and Technologies (NIST), is based on the results and experience gained from the successful Comparative Soot Diagnostics experiment, which was flown as part of the USMP-3 (United States Microgravity Payload 3) mission on space shuttle flight STS-75. The Smoke experiment is designed to determine the particle size distributions of the smokes generated from a variety of overheated spacecraft materials and from microgravity fires. The objective is to provide the data that spacecraft designers need to properly design and implement fire detection in spacecraft. This investigation will also evaluate the performance of the smoke detectors currently in use aboard the space shuttle and ISS for the test materials in a microgravity environment.

Meteoroid/space debris impacts on MSFC LDEF experiments

NASA Technical Reports Server (NTRS)

Finckenor, Miria

1991-01-01

The numerous meteoroid and space debris impacts found on AO171, AO034, S0069, and other MSFC experiments are examined. Besides those impacts found by the Meteoroid and Debris Special Investigative Group at KSC, numerous impacts of less than 0.5 mm were found and photographed. The flux and size distribution of impacts are presented as well as EDS analysis of impact residue. Emphasis is on morphology of impacts in the various materials, including graphite/epoxy composites, polymeric materials, optical coatings, thin films, and solar cells.

Investigation of Plasma Facing Components in Plasma Focus Operation

NASA Astrophysics Data System (ADS)

Roshan, M. V.; Babazadeh, A. R.; Kiai, S. M. Sadat; Habibi, H.; Mamarzadeh, M.

2007-09-01

Both aspects of the plasma-wall interactions, counter effect of plasma and materials, have been considered in our experiments. The AEOI plasma focus, Dena, has Filippov-type electrodes. The experimental results verify that neutron production increases using tungsten as an anode insert material, compared to the copper one. The experiments show decrement of the hardness of Aluminum targets outward the sides, from 135 to 78 in Vickers scale. The sputtering yield is about 0.0065 for deuteron energy of 50 keV.

Working memory affects false memory production for emotional events.

PubMed

Mirandola, Chiara; Toffalini, Enrico; Ciriello, Alfonso; Cornoldi, Cesare

2017-01-01

Whereas a link between working memory (WM) and memory distortions has been demonstrated, its influence on emotional false memories is unclear. In two experiments, a verbal WM task and a false memory paradigm for negative, positive or neutral events were employed. In Experiment 1, we investigated individual differences in verbal WM and found that the interaction between valence and WM predicted false recognition, with negative and positive material protecting high WM individuals against false remembering; the beneficial effect of negative material disappeared in low WM participants. In Experiment 2, we lowered the WM capacity of half of the participants with a double task request, which led to an overall increase in false memories; furthermore, consistent with Experiment 1, the increase in negative false memories was larger than that of neutral or positive ones. It is concluded that WM plays a critical role in determining false memory production, specifically influencing the processing of negative material.

MISSE 6, 7 and 8 Materials Sample Experiments from the International Space Station Materials and Processes Team

NASA Technical Reports Server (NTRS)

Kravchenko, Michael; ORourke, Mary Jane; Golden, Johnny; Finckenor, Miria; Leatherwood, Michael; Alred, John

2010-01-01

The International Space Station Materials and Processes (ISS M&P) team has multiple material samples on MISSE 6, 7 and 8 to observe Low Earth Orbit (LEO) environmental effects on Space Station materials. Optical properties, thickness/mass loss, surface elemental analysis, visual and microscopic analysis for surface change are some of the techniques employed in this investigation. The ISS M&P team has participated in previous MISSE activities in order to better characterize the LEO effects on Space Station materials. This investigation will further this effort. Results for the following MISSE 6 samples materials will be presented: a comparison of anodize and chemical conversion coatings on various aluminum alloys, electroless nickel; AZ93 white ceramic thermal control coating with and without Teflon; Hyzod(TM) polycarbonate used to temporarily protect ISS windows; Russian quartz window material; reformulated Teflon (TM) coated Beta Cloth (Teflon TM without perfluorooctanoic acid (PFOA)) and a Dutch version of beta cloth. Discussion for current and future MISSE materials experiments will be presented. MISSE 7 samples are: deionized water sealed anodized aluminum Photofoil(TM); indium tin oxide (ITO)- coated Kapton(TM) used as thermo-optical surfaces; mechanically scribed tin-plated beryllium-copper samples for "tin pest" growth ( alpha/Beta transformation); Crew Exploration Vehicle (CEV) parachute soft goods. MISSE 8 sample: exposed "scrim cloth" (fiberglass weave) from the ISS solar array wing material, Davlyn fiberglass sleeve material, Permacel and Intertape protective tapes, and ITO-coated Kapton.

Transport and retention of surfactant- and polymer-stabilized engineered silver nanoparticles in silicate-dominated aquifer material

USDA-ARS?s Scientific Manuscript database

Packed column experiments were conducted to investigate the transport and blocking behavior of surfactant- and polymer-stabilized engineered silver nanoparticles (Ag-ENPs) in saturated natural aquifer material with varying silt and clay content, background solution chemistry, and flow velocity. Brea...

Laboratory-Based and Autobiographical Retrieval Tasks Differ Substantially in Their Neural Substrates

ERIC Educational Resources Information Center

McDermott, Kathleen B.; Szpunar, Karl K.; Christ, Shawn E.

2009-01-01

In designing experiments to investigate retrieval of event memory, researchers choose between utilizing laboratory-based methods (in which to-be-remembered materials are presented to participants) and autobiographical approaches (in which the to-be-remembered materials are events from the participant's pre-experimental life). In practice, most…

Technique development for conducting mechanical tests to study the pore formation process in case of material fracture

NASA Astrophysics Data System (ADS)

Magomedova, D. K.; Efimov, M. A.; Murashkin, M. Yu.

2018-05-01

The main purpose of this work was the development of an experimental technique for search and analysis of pore formation in the presented material. Geometry of the samples, the procedure of experiment and processing the samples for investigation were developed.

The Early Years: Becoming Attuned to Sound

ERIC Educational Resources Information Center

Ashbrook, Peggy

2014-01-01

Exploration of making and changing sounds is part of the first-grade performance expectation 1-PS4-1, "Plan and conduct investigations to provide evidence that vibrating materials can make sound and that sound can make materials vibrate" (NGSS Lead States 2013, p. 10; see Internet Resource). Early learning experiences build toward…

The influence of expertise and of physical complexity on visual short-term memory consolidation.

PubMed

Sun, Huiming; Zimmer, Hubert D; Fu, Xiaolan

2011-04-01

We investigated whether the expertise of a perceiver and the physical complexity of a stimulus influence consolidation of visual short-term memory (VSTM) in a S1-S2 (Stimulus 1-Stimulus 2) change detection task. Consolidation is assumed to make transient perceptual representations in VSTM more durable, and it is investigated by postexposure of a mask shortly after offset of the perceived stimulus (S1; 17 to 483 ms). We presented colours, Chinese characters, pseudocharacters, and novel symbols to novices (Germans) or experts of Chinese language (Chinese readers). Physical complexity was manipulated by the number of strokes. Unfamiliar material was remembered worse than familiar material (Experiments 1, 2, and 3). For novices the absolute VSTM performance was better for physically simple than for complex material, whereas for experts the complexity did not matter-Chinese readers memorized Chinese characters (Experiment 3). Articulatory suppression did not change these effects (Experiment 2). We always observed a strong effect of SOA, but this effect was influenced neither by physical complexity nor by expertise; only the length of the interstimulus interval between S1 and the mask was relevant. This was observed even with short stimulus onset asynchrony (SOA) of 100 ms (Experiment 2) and in comparing colours and characters (Experiment 5). However, masks impaired memory if they were presented at the locations of the to-be-memorized items, but not beside them-that is, interference was location-based (Experiment 6). We explain the effect of SOA by the assumption that it takes time to stop encoding of information presented at item locations with the offset of S1. The increasing resistance against interference by irrelevant material appears as consolidation of S1.

Gas-Cooled Reactor Programs annual progress report for period ending December 31, 1973. [HTGR fuel reprocessing, fuel fabrication, fuel irradiation, core materials, and fission product distribution; GCFR fuel irradiation and steam generator modeling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kasten, P.R.; Coobs, J.H.; Lotts, A.L.

1976-04-01

Progress is summarized in studies relating to HTGR fuel reprocessing, refabrication, and recycle; HTGR fuel materials development and performance testing; HTGR PCRV development; HTGR materials investigations; HTGR fuel chemistry; HTGR safety studies; and GCFR irradiation experiments and steam generator modeling.

Basic and Applied Materials Science Research Efforts at MSFC Germane to NASA Goals

NASA Technical Reports Server (NTRS)

2003-01-01

Presently, a number of investigations are ongoing that blend basic research with engineering applications in support of NASA goals. These include (1) "Pore Formation and Mobility (PFMI) " An ISS Glovebox Investigation" NASA Selected Project - 400-34-3D; (2) "Interactions Between Rotating Bodies" Center Director's Discretionary Fund (CDDF) Project - 279-62-00-16; (3) "Molybdenum - Rhenium (Mo-Re) Alloys for Nuclear Fuel Containment" TD Collaboration - 800-11-02; (4) "Fabrication of Alumina - Metal Composites for Propulsion Components" ED Collaboration - 090-50-10; (5) "Radiation Shielding for Deep-Space Missions" SD Effort; (6) "Other Research". In brief, "Pore Formation and Mobility" is an experiment to be conducted in the ISS Microgravity Science Glovebox that will systematically investigate the development, movement, and interactions of bubbles (porosity) during the controlled directional solidification of a transparent material. In addition to promoting our general knowledge of porosity physics, this work will serve as a guide to future ISS experiments utilizing metal alloys. "Interactions Between Rotating Bodies" is a CDDF sponsored project that is critically examining, through theory and experiment, claims of "new" physics relating to gravity modification and electric field effects. "Molybdenum - Rhenium Alloys for Nuclear Fuel Containment" is a TD collaboration in support of nuclear propulsion. Mo-Re alloys are being evaluated and developed for nuclear fuel containment. "Fabrication of Alumina - Metal Composites for Propulsion Components" is an ED collaboration with the intent of increasing strength and decreasing weight of metal engine components through the incorporation of nanometer-sized alumina fibers. "Radiation Shielding for Deep-Space Missions" is an SD effort aimed at minimizing the health risk from radiation to human space voyagers; work to date has been primarily programmatic but experiments to develop hydrogen-rich materials for shielding are planned. "Other Research" includes: BUNDLE (Bridgman Unidirectional Dendrite in a Liquid Experiment) activities (primarily crucible development), vibrational float-zone processing (with Vanderbilt University), use of ultrasonics in materials processing (with UAH), rotational effects on microstructural development, and application of magnetic fields for mixing.

Electrochromic WO[subscript 3] Films: Nanotechnology Experiments in Instrumental Analysis and Physical Chemistry Laboratories

ERIC Educational Resources Information Center

Hepel, Maria

2008-01-01

This experiment teaches students the methodology of investigating novel properties of materials using new instrumental techniques: atomic force microscopy (AFM), electrochemical quartz crystal nanobalance (EQCN), voltammetric techniques (linear potential scan and chronoamperometry), and light reflectance measurements. The unique capabilities of…

Suitable Class Experiments in Biochemistry for High-school Chemistry and Biology Courses.

ERIC Educational Resources Information Center

Myers, A.

1987-01-01

Illustrates the scope of experimental investigations for biochemistry education in high school biology and chemistry courses. Gives a brief overview of biochemistry experiments with proteins, enzymes, carbohydrates, lipids, nucleic acids, vitamins, metabolism, electron transport, and photosynthesis including materials, procedures, and outcomes.…

Isotropic thin-walled pressure vessel experiment

NASA Technical Reports Server (NTRS)

Denton, Nancy L.; Hillsman, Vernon S.

1992-01-01

The objectives are: (1) to investigate the stress and strain distributions on the surface of a thin walled cylinder subject to internal pressure and/or axial load; and (2) to relate stress and strain distributions to material properties and cylinder geometry. The experiment, supplies, and procedure are presented.

Influencing Factors and Workpiece's Microstructure in Laser-Assisted Milling of Titanium

NASA Astrophysics Data System (ADS)

Wiedenmann, R.; Liebl, S.; Zaeh, M. F.

Today's lightweight components have to withstand increasing mechanical and thermal loads. Therefore, advanced materials substitute conventional materials like steel or aluminum alloys. Using these high-performance materials the associated costs become prohibitively high. This paper presents the newest fundamental investigations on the hybrid process 'laser-assisted milling' which is an innovative technique to process such materials. The focus is on the validation of a numerical database for a CAD/CAM process control unit which is calculated by using simulation. Prior to that, the influencing factors on a laser-assisted milling process are systematically investigated using Design of Experiments (DoE) to identify the main influencing parameters coming from the laser and the milling operation.

Mechanic of Granular Materials (MGM) Investigator

NASA Technical Reports Server (NTRS)

2000-01-01

Key persornel in the Mechanics of Granular Materials (MGM) experiment are Mark Lankton (Program Manager at University Colorado at Boulder), Susan Batiste (research assistance, UCB), and Stein Sture (principal investigator). Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. MGM experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that cannot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. (Credit: University of Colorado at Boulder).

How to Do It. Plant Eco-Physiology: Experiments on Crassulacean Acid Metabolism, Using Minimal Equipment.

ERIC Educational Resources Information Center

Friend, Douglas J. C.

1990-01-01

Features of Crassulacean Acid Metabolism plants are presented. Investigations of a complex eco-physiological plant adaptation to the problems of growth in an arid environment are discussed. Materials and procedures for these investigations are described. (CW)

Video requirements for materials processing experiments in the space station US laboratory

NASA Technical Reports Server (NTRS)

Baugher, Charles R.

1989-01-01

Full utilization of the potential of the materials research on the Space Station can be achieved only if adequate means are available for interactive experimentation between the science facilities and ground-based investigators. Extensive video interfaces linking these three elements are the only alternative for establishing a viable relation. Because of the limit in the downlink capability, a comprehensive complement of on-board video processing, and video compression is needed. The application of video compression will be an absolute necessity since it's effectiveness will directly impact the quantity of data which will be available to ground investigator teams, and their ability to review the effects of process changes and the experiment progress. Video data compression utilization on the Space Station is discussed.

Syncom 4 deploy, LDEF retrieval highlight 10-day Columbia flight

NASA Technical Reports Server (NTRS)

1989-01-01

The objectives of Space Shuttle Mission STS-32 are described along with major flight activities, prelaunch and launch operations, trajectory sequence of events, and landing and post-landing operations. The primary objectives of STS-32 are the deployment of a Navy synchronous communications satellite (Syncom 4) and the retrieval of the Long Duration Exposure Facility (LDEF) launched from the Challenger in April 1984. Secondary STS-32 payloads include a protein crystal growth experiment, the Fluids Experiment Apparatus (FEA) for the investigation of microgravity materials processing, the Mesoscale Lighting Experiment, the Latitude-Longitude Locator Experiment, the Americal Flight Echocardiograph, and an experiment to investigate neurospora circadian rhythms in a microgravity environment.

Spacelab J experiment descriptions

NASA Technical Reports Server (NTRS)

Miller, Teresa Y. (Editor)

1993-01-01

Brief descriptions of the experiment investigations for the Spacelab J Mission which was launched from the Kennedy Space Center aboard the Endeavour in Sept. 1992 are presented. Experiments cover the following: semiconductor crystals; single crystals; superconducting composite materials; crystal growth; bubble behavior in weightlessness; microgravity environment; health monitoring of Payload Specialists; cultured plant cells; effect of low gravity on calcium metabolism and bone formation; and circadian rhythm.

Using Modern Solid-State Analytical Tools for Investigations of an Advanced Carbon Capture Material: Experiments for the Inorganic Chemistry Laboratory

ERIC Educational Resources Information Center

Wriedt, Mario; Sculley, Julian P.; Aulakh, Darpandeep; Zhou, Hong-Cai

2016-01-01

A simple and straightforward synthesis of an ultrastable porous metal-organic framework (MOF) based on copper(II) and a mixed N donor ligand system is described as a laboratory experiment for chemistry undergraduate students. These experiments and the resulting analysis are designed to teach students basic research tools and procedures while…

The effect of material hardship on child protective service involvement.

PubMed

Yang, Mi-Youn

2015-03-01

This study employs four waves of survey data on 1,135 families from the Illinois Families Study, a longitudinal panel study of Temporary Assistance for Needy Families in Illinois. This study explores the following issues within this low-income population: (1) whether material hardships are associated with child protective services (CPS) investigations, (2) whether the effect of material hardship on CPS differs by the type of child maltreatment investigated, and (3) whether psychological distress mediates the association between material hardship and CPS involvement. Results from pooled and fixed effects logistic regressions suggest that caregivers who experience material hardship are more likely to become involved in CPS. In general, investigated neglect reports are responsive to particular types of hardship such as housing and food, while investigated physical abuse reports are responsive to levels of hardship regardless of specific types. The association between material hardship and CPS involvement is not fully explained by depressive symptoms or parenting stress. The study results suggest that in order to prevent child maltreatment, it may be necessary to address a family's unmet material needs through economic support interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Science of Detached Bridgman Growth and Solutocapillary Convection in Solid Solution Crystals

NASA Technical Reports Server (NTRS)

Szofran, F. R.; Volz, M. P.; Cobb, S. D.; Motakef, S.; Croell, A.; Dold, P.

2001-01-01

Bridgman and Float-zone crystal growth experiments are planned for NASA's First Materials Science Research Rack using the European Space Agency's Materials Science Laboratory with the Low Gradient Furnace (LGF) and Float Zone Furnace with Rotating Magnetic Field (FMF) inserts, respectively. Samples will include germanium and germanium-silicon alloys with up to 10 atomic percent silicon. The Bridgman part of the investigation includes detached growth samples and so there will be a solid-liquid-gas tri-junction in those experiments just as there will be in all float-zone experiments. There are other similarities as well as significant differences between the types of growth that will be discussed. The presentation will call attention to the reasons that experiments in microgravity will provide information unattainable from Earth-based experiments.

Power-law viscous materials for analogue experiments: New data on the rheology of highly-filled silicone polymers

NASA Astrophysics Data System (ADS)

Boutelier, D.; Schrank, C.; Cruden, A.

2008-03-01

The selection of appropriate analogue materials is a central consideration in the design of realistic physical models. We investigate the rheology of highly-filled silicone polymers in order to find materials with a power-law strain-rate softening rheology suitable for modelling rock deformation by dislocation creep and report the rheological properties of the materials as functions of the filler content. The mixtures exhibit strain-rate softening behaviour but with increasing amounts of filler become strain-dependent. For the strain-independent viscous materials, flow laws are presented while for strain-dependent materials the relative importance of strain and strain rate softening/hardening is reported. If the stress or strain rate is above a threshold value some highly-filled silicone polymers may be considered linear visco-elastic (strain independent) and power-law strain-rate softening. The power-law exponent can be raised from 1 to ˜3 by using mixtures of high-viscosity silicone and plasticine. However, the need for high shear strain rates to obtain the power-law rheology imposes some restrictions on the usage of such materials for geodynamic modelling. Two simple shear experiments are presented that use Newtonian and power-law strain-rate softening materials. The results demonstrate how materials with power-law rheology result in better strain localization in analogue experiments.

Exposure of LDEF materials to atomic oxygen: Results of EOIM 3

NASA Technical Reports Server (NTRS)

Jaggers, C. H.; Meshishnek, M. J.

1995-01-01

The third Effects of Oxygen Atom Interaction with Materials (EOIM 3) experiment flew on STS-46 from July 31 to August 8, 1992. The EOIM-3 sample tray was exposed to the low-earth orbit space environment for 58.55 hours at an altitude of 124 nautical miles resulting in a calculated total atomic oxygen (AO) fluence of 1.99 x 10(exp 20) atoms/sq cm. Five samples previously flown on the Long Duration Exposure Facility (LDEF) Experiment M0003 were included on the Aerospace EOIM 3 experimental tray: (1) Chemglaze A276 white thermal control paint from the LDEF trailing edge (TE); (2) S13GLO white thermal control paint from the LDEF TE; (3) S13GLO from the LDEF leading edge (LE) with a visible contamination layer from the LDEF mission; (4) Z306 black thermal control paint from the LDEF TE with a contamination layer from the LDEF mission; and (5) anodized aluminum from the LDEF TE with a contamination layer from the LDEF mission. The purpose of this experiment was twofold: (l) investigate the response of trailing edge LDEF materials to atomic oxygen exposure, thereby simulating LDEF leading edge phenomena; (2) investigate the response of contaminated LDEF samples to atomic oxygen in attempts to understand LDEF contamination-atomic oxygen interactions. This paper describes the response of these materials to atomic oxygen exposure, and compares the results of the EOIM 3 experiment to the LDEF mission and to ground-based atomic oxygen exposure studies.

Orbital atomic oxygen effects on materials: An overview of MSFC experiments on the STS-46 EOIM-3

NASA Astrophysics Data System (ADS)

Linton, Roger C.; Vaughn, Jason A.; Finckenor, Miria M.; Kamenetzky, Rachel R.; Dehaye, Robert F.; Whitaker, Ann F.

1995-02-01

The third Evaluation of Oxygen Interaction with Materials experiment was flown on Space Shuttle Mission STS-46 (July 31 - August 8, 1992), representing a joint effort of several NASA centers, universities, and contractors. This array of active instrumentation and material exposure sub-assemblies was integrated as a Shuttle cargo bay pallet experiment for investigating the effects of orbital atomic oxygen on candidate space materials. Marshall Space Flight Center contributed several passive exposure trays of material specimens, uniform stress and static stress material exposure fixtures, the Atomic Oxygen Resistance Monitor (AORM), and specimens of thermal coatings for the EOIM-3 variable exposure mechanisms. As a result of 42 hours of spacecraft velocity vector-oriented exposure during the later phases of the STS-46 mission in LEO, EOIM-3 materials were exposed to an atomic oxygen fluence of 2.2 x 10(exp 20) atoms/sq cm. In this paper, an overview is presented of the technical approaches and results from analyses of the MSFC flight specimens, fixtures, and the AORM. More detailed results from earlier EOIM missions, the LDEF, and from laboratory testing are included in associated papers of this conference session.

Orbital atomic oxygen effects on materials: An overview of MSFC experiments on the STS-46 EOIM-3

NASA Technical Reports Server (NTRS)

Linton, Roger C.; Vaughn, Jason A.; Finckenor, Miria M.; Kamenetzky, Rachel R.; Dehaye, Robert F.; Whitaker, Ann F.

1995-01-01

The third Evaluation of Oxygen Interaction with Materials experiment was flown on Space Shuttle Mission STS-46 (July 31 - August 8, 1992), representing a joint effort of several NASA centers, universities, and contractors. This array of active instrumentation and material exposure sub-assemblies was integrated as a Shuttle cargo bay pallet experiment for investigating the effects of orbital atomic oxygen on candidate space materials. Marshall Space Flight Center contributed several passive exposure trays of material specimens, uniform stress and static stress material exposure fixtures, the Atomic Oxygen Resistance Monitor (AORM), and specimens of thermal coatings for the EOIM-3 variable exposure mechanisms. As a result of 42 hours of spacecraft velocity vector-oriented exposure during the later phases of the STS-46 mission in LEO, EOIM-3 materials were exposed to an atomic oxygen fluence of 2.2 x 10(exp 20) atoms/sq cm. In this paper, an overview is presented of the technical approaches and results from analyses of the MSFC flight specimens, fixtures, and the AORM. More detailed results from earlier EOIM missions, the LDEF, and from laboratory testing are included in associated papers of this conference session.

Representing ductile damage with the dual domain material point method

DOE PAGES

Long, C. C.; Zhang, D. Z.; Bronkhorst, C. A.; ...

2015-12-14

In this study, we incorporate a ductile damage material model into a computational framework based on the Dual Domain Material Point (DDMP) method. As an example, simulations of a flyer plate experiment involving ductile void growth and material failure are performed. The results are compared with experiments performed on high purity tantalum. We also compare the numerical results obtained from the DDMP method with those obtained from the traditional Material Point Method (MPM). Effects of an overstress model, artificial viscosity, and physical viscosity are investigated. Our results show that a physical bulk viscosity and overstress model are important in thismore » impact and failure problem, while physical shear viscosity and artificial shock viscosity have negligible effects. A simple numerical procedure with guaranteed convergence is introduced to solve for the equilibrium plastic state from the ductile damage model.« less

Rheology of Coating Materials and Their Coating Characteristics

NASA Astrophysics Data System (ADS)

Grabsch, C.; Grüner, S.; Otto, F.; Sommer, K.

2008-07-01

Lots of particles used in the pharmaceutical and the food industry are coated to protect the core material. But almost no investigations about the coating material behavior do exist. In this study the focus was on the rheological material properties of fat based coating materials. Rotational shear experiments to determine the viscosity of a material were compared to oscillatory shear tests to get information about the vicoelastic behavior of the coating materials. At the liquid state the viscosity and the viscoelastic properties showed a good analogy. The viscoelastic properties of the solid coating materials yielded differences between materials that have the same properties at the liquid state.

The Separatory Cylinder: A Novel Solvent Extraction System for the Study of Chemical Equilibrium in Solution.

ERIC Educational Resources Information Center

Cwikel, Dori; And Others

1986-01-01

Dicusses the use of the separatory cylinder in student laboratory experiments for investigating equilibrium distribution of a solute between immiscible phases. Describes the procedures for four sets of experiments of this nature. Lists of materials needed and quantities of reagents are provided. (TW)

Chemical pump study

NASA Technical Reports Server (NTRS)

Bergquist, L. E.

1973-01-01

Sorption pumps applicable to the Pioneer Venus Mass Spectrometer Experiment were investigated. The pump requirements are discussed, and a survey of the existing pumps presented. Zirconium and zirconium graphite products were found to be the most promising among the getter materials surveyed. A preliminary pump design for the noble gas experiment is discussed.

(Re)constructing Strategies: A Methodological Experiment on Representation

ERIC Educational Resources Information Center

Holge-Hazelton, Bibi; Krojer, Jo

2008-01-01

The article describes an experiment in which two researchers engaged in developing poetic forms of representing qualitative empirical research switch their individually produced empirical material and work simultaneously on each other's products. The intention is to investigate what we, as researchers, are adding to and extracting from the…

Environmental Experiments...from Edison.

ERIC Educational Resources Information Center

Schultz, Robert F.

Background information, lists of materials needed, and procedures are provided for 12 experiments which focus on various aspects of pollution and the environment. Topics considered in the investigations are: (1) solids in the air; (2) effect of air pollution on nylon; (3) measuring lung capacity; (4) an electrical smoke trap; (5) photosynthesis;…

Evaluation of adhesive materials used on the Long Duration Exposure Facility

NASA Technical Reports Server (NTRS)

Dursch, H. W.; Keough, B. K.; Pippin, H. G.

1995-01-01

The adhesive and adhesive-like materials flown on LDEF included epoxies and silicones (including lap shear specimens), conformal coatings, potting compounds, and several tapes and transfer films. With the exception of the lap shear specimens, these materials were used in the fabrication and assembly of the experiments such as bonding thermal control surfaces to other hardware and holding individual specimens in place, similar to applications on other spacecraft. Typically, the adhesives were not exposed to solar radiation or atomic oxygen. Only one adhesive system was used in a structural application. This report documents all results of the Materials and Systems SIG investigation into the effect of long term low Earth orbit (LEO) exposure of these materials. Results of this investigation show that if the material was shielded from exposure to LDEF's external environment, the 69 month exposure to LEO had, in most cases, minimal effect on the material.

Nile River, Lake Nasser, North Sudan and Lower Egypt

NASA Image and Video Library

1992-11-01

STS052-152-026 (22Oct-1 Nov 1992) --- Backdropped over eastern Egypt, the Canadian-built remote manipulator system (RMS) attached to NASA's Earth-orbiting Space Shuttle Columbia displays a Canadian Space Agency (CSA) experiment. Materials Exposure in Low Earth Orbit (MELEO) is one of a number of Canadian experiments which flew aboard Columbia for the ten-day STS-52 mission. Principal investigator for the experiment is Dr. David G. Zimick of the CSA. Plastic and composite materials used on the external surfaces of spacecraft have been found to degrade in the harsh environment of space. Evidence suggests that this degradation is caused by interaction with atomic oxygen which induces damaging chemical and physical reactions. The result is a loss in mass, strength, stiffness and stability of size and shape. During the mission, MELEO exposed over 350 material specimens mounted on "witness plates" on the RMS arm. The specimen collection will be analyzed in the weeks following the mission. Typical spacecraft materials and new developments in protective measures against atomic oxygen were tested as part of the MELEO experiment.

Influence of weight and type of planting material on fruit quality and its heterogeneity in pineapple [Ananas comosus (L.) Merrill].

PubMed

Fassinou Hotegni, V Nicodème; Lommen, Willemien J M; Agbossou, Euloge K; Struik, Paul C

2014-01-01

Cultural practices can affect the quality of pineapple fruits and its variation. The objectives of this study were to investigate (a) effects of weight class and type of planting material on fruit quality, heterogeneity in quality and proportion and yield of fruits meeting European export standards, and (b) the improvement in quality, proportion and yield of fruits meeting export standards when flowering was induced at optimum time. Experiments were conducted in Benin with cvs Sugarloaf (a Perola type) and Smooth Cayenne. In cv. Sugarloaf, experimental factors were weight class of planting material (light, mixed, heavy) and time of flowering induction (farmers', optimum) (Experiment 1). In cv. Smooth Cayenne an additional experimental factor was the type of planting material (hapas, ground suckers, a mixture of the two) (Experiment 2). Fruits from heavy planting material had higher infructescence and fruit weights, longer infructescences, shorter crowns, and smaller crown: infructescence length than fruits from light planting material. The type of planting material in Experiment 2 did not significantly affect fruit quality except crown length: fruits from hapas had shorter crowns than those from ground suckers. Crops from heavy planting material had a higher proportion and yield of fruits meeting export standards than those from other weight classes in Experiment 1 only; also the type of planting material in Experiment 2 did not affect these variates. Heterogeneity in fruit quality was usually not reduced by selecting only light or heavy planting material instead of mixing weights; incidentally the coefficient of variation was significantly reduced in fruits from heavy slips only. Heterogeneity was also not reduced by not mixing hapas and ground suckers. Flowering induction at optimum time increased the proportion and yield of fruits meeting export standards in fruits from light and mixed slip weights and in those from the mixture of heavy hapas plus ground suckers.

Influence of weight and type of planting material on fruit quality and its heterogeneity in pineapple [Ananas comosus (L.) Merrill

PubMed Central

Fassinou Hotegni, V. Nicodème; Lommen, Willemien J. M.; Agbossou, Euloge K.; Struik, Paul C.

2015-01-01

Cultural practices can affect the quality of pineapple fruits and its variation. The objectives of this study were to investigate (a) effects of weight class and type of planting material on fruit quality, heterogeneity in quality and proportion and yield of fruits meeting European export standards, and (b) the improvement in quality, proportion and yield of fruits meeting export standards when flowering was induced at optimum time. Experiments were conducted in Benin with cvs Sugarloaf (a Perola type) and Smooth Cayenne. In cv. Sugarloaf, experimental factors were weight class of planting material (light, mixed, heavy) and time of flowering induction (farmers', optimum) (Experiment 1). In cv. Smooth Cayenne an additional experimental factor was the type of planting material (hapas, ground suckers, a mixture of the two) (Experiment 2). Fruits from heavy planting material had higher infructescence and fruit weights, longer infructescences, shorter crowns, and smaller crown: infructescence length than fruits from light planting material. The type of planting material in Experiment 2 did not significantly affect fruit quality except crown length: fruits from hapas had shorter crowns than those from ground suckers. Crops from heavy planting material had a higher proportion and yield of fruits meeting export standards than those from other weight classes in Experiment 1 only; also the type of planting material in Experiment 2 did not affect these variates. Heterogeneity in fruit quality was usually not reduced by selecting only light or heavy planting material instead of mixing weights; incidentally the coefficient of variation was significantly reduced in fruits from heavy slips only. Heterogeneity was also not reduced by not mixing hapas and ground suckers. Flowering induction at optimum time increased the proportion and yield of fruits meeting export standards in fruits from light and mixed slip weights and in those from the mixture of heavy hapas plus ground suckers. PMID:25653659

Chinese Preschoolers' Resource Allocation in the Face of Existing Inequality under Collaborative and Noncollaborative Contexts

ERIC Educational Resources Information Center

Chai, Qiao; He, Jie

2017-01-01

The current study investigated the stage at which Chinese preschoolers started considering recipients' material welfare and minimizing existing inequalities under both noncollaborative and collaborative contexts. Also, it analyzed how they behaved when recipients' material welfare was in conflict with merit or equality rule. Experiment 1 found…

Modality, Probability, and Mental Models

ERIC Educational Resources Information Center

Hinterecker, Thomas; Knauff, Markus; Johnson-Laird, P. N.

2016-01-01

We report 3 experiments investigating novel sorts of inference, such as: A or B or both. Therefore, possibly (A and B). Where the contents were sensible assertions, for example, "Space tourism will achieve widespread popularity in the next 50 years or advances in material science will lead to the development of antigravity materials in the…

Basic Skills Applications in Career Investigation: Mathematics, Science, Social Studies, Communications, Productive Work Habits. Revised.

ERIC Educational Resources Information Center

Hendrix, Mary W.

These materials allow instructors to provide learning experiences that stress the equal importance of academic and vocational education and the personal and social matters related to the work ethic. Instructional materials are provided in 15 clusters: agribusiness and natural resources; business and office; communications and media; construction;…

Visual Cues, Student Sex, Material Taught, and the Magnitude of Teacher Expectancy Effects.

ERIC Educational Resources Information Center

Badini, Aldo A.; Rosenthal, Robert

1989-01-01

Conducts an experiment on teacher expectancy effects to investigate the simultaneous effects of student gender, communication channel, and type of material taught (vocabulary and reasoning). Finds that the magnitude of teacher expectation effects was greater when students had access to visual cues, especially when the students were female. (MS)

Teacher Learning of Subject Matter Knowledge through an Educative Curriculum

ERIC Educational Resources Information Center

Noh, Jihwa; Webb, Matthew

2015-01-01

The authors examined the characterization of mathematical knowledge of teachers using educative curriculum materials. In particular, they investigated knowledge of change and rate of change (in the context of algebra and functions) of 12 teachers with differing levels of experience. Participants used a same set of curriculum materials that embed…

The Impact of Differentiated Instructional Materials on English Language Learner (ELL) Students' Comprehension of Science Laboratory Tasks

ERIC Educational Resources Information Center

Manavathu, Marian; Zhou, George

2012-01-01

Through a qualitative research design, this article investigates the impacts of differentiated laboratory instructional materials on English language learners' (ELLs) laboratory task comprehension. The factors affecting ELLs' science learning experiences are further explored. Data analysis reveals a greater degree of laboratory task comprehension…

Study of PRIMAVERA steel samples by a positron annihilation spectroscopy technique

NASA Astrophysics Data System (ADS)

Grafutin, V.; Ilyukhina, O.; Krsjak, V.; Burcl, R.; Hähner, P.; Erak, D.; Zeman, A.

2010-11-01

In the present article, a positron annihilation spectroscopy investigation of VVER-440/230 weld materials is discussed. Important characteristics of metals such as Fermi energy, concentration of electrons in the conduction band, size and concentration of defects were experimentally determined for three model materials with higher level of copper (0.16 wt.%) and phosphorus (0.027-0.038 wt.%). The impact of neutron irradiation and subsequent annealing on crystal lattice parameters was investigated. The experiments with the angular correlation of positron annihilation radiation (ACAR) complement the published positron annihilation spectroscopy (PAS) studies of the radiation treated VVER materials as well as previous experiments on PRIMAVERA materials. The availability of the experimental reactor to prepare strong 64Cu positron sources provided for unique experimental conditions, such as good resolution of spectra (0.4 mrad) and reasonable short time of measurement (36 h). The present paper aims to contribute to further understanding of RPV (reactor pressure vessel) steels behaviour under irradiation conditions as well as annealing recovery procedures, which have already been applied at several VVER NPP units in Europe.

Experimental investigation of Rayleigh Taylor instability in elastic-plastic materials

NASA Astrophysics Data System (ADS)

Haley, Aaron Alan; Banerjee, Arindam

2010-11-01

The interface of an elastic-plastic plate accelerated by a fluid of lower density is Rayleigh Taylor (RT) unstable, the growth being mitigated by the mechanical strength of the plate. The instability is observed when metal plates are accelerated by high explosives, in explosive welding, and in volcanic island formation due to the strength of the inner crust. In contrast to the classical case involving Newtonian fluids, RT instability in accelerated solids is not well understood. The difficulties for constructing a theory for the linear growth phase in solids is essentially due to the character of elastic-plastic constitutive properties which has a nonlinear dependence on the magnitude of the rate of deformation. Experimental investigation of the phenomena is difficult due to the exceedingly small time scales (in high energy density experiments) and large measurement uncertainties of material properties. We performed experiments on our Two-Wheel facility to study the linear stage of the incompressible RT instability in elastic-plastic materials (yogurt) whose properties were well characterized. Rotation of the wheels imparted a constant centrifugal acceleration on the material interface that was cut with a small sinusoidal ripple. The controlled initial conditions and precise acceleration amplitudes are levied to investigate transition from elastic to plastic deformation and allow accurate and detailed measurements of flow properties.

Containerless Liquid-Phase Processing of Ceramic Materials

NASA Technical Reports Server (NTRS)

Weber, J. K. Richard (Principal Investigator); Nordine, Paul C.

1996-01-01

The present project builds on the results of research supported under a previous NASA grant to investigate containerless liquid-phase processing of molten ceramic materials. The research used an aero-acoustic levitator in combination with cw CO2 laser beam heating to achieve containerless melting, superheating, undercooling, and solidification of poorly-conducting solids and liquids. Experiments were performed on aluminum oxide, binary aluminum oxide-silicon dioxide materials, and oxide superconductors.

Deformation profiles of elastic cylindrical tubes filled with granular media under an overload

NASA Astrophysics Data System (ADS)

Álvarez Salazar, V. Salomón; Medina, Abraham; Klapp, Jaime

2017-06-01

The deformation of a thin-walled vertical tube, filled with a liquid or a cohesionless granular material is investigated theoretically and experimentally. Experiments with an overload and without it were made with latex tubes filled with water or spherical glass beads and the results were compared with the theoretical profile derived from the Janssen model. The results suggest that the soft elastic tubes could provide a simple and convenient means to investigate the forces that arise in different materials.

Flexible thermal protection materials for entry systems

NASA Astrophysics Data System (ADS)

Kourtides, Demetrius A.

1993-02-01

Current programs addressed in aeroassist flight experiment are: (1) evaluation of thermal performance of advanced rigid and flexible insulations and reflective coating; (2) investigation of lighter than baseline materials; (3) investigation of rigid insulations which perform well; (4) study of flexible insulations which require ceramic coating; and (5) study of reflective coating effective at greater than 15 percent. In National Aerospace Plane (NASP), the programs addressed are: (1) high and low temperature insulations; and (2) attachment/standoff methodology critical which affects thermal performance.

Flexible thermal protection materials for entry systems

NASA Technical Reports Server (NTRS)

Kourtides, Demetrius A.

1993-01-01

Current programs addressed in aeroassist flight experiment are: (1) evaluation of thermal performance of advanced rigid and flexible insulations and reflective coating; (2) investigation of lighter than baseline materials; (3) investigation of rigid insulations which perform well; (4) study of flexible insulations which require ceramic coating; and (5) study of reflective coating effective at greater than 15 percent. In National Aerospace Plane (NASP), the programs addressed are: (1) high and low temperature insulations; and (2) attachment/standoff methodology critical which affects thermal performance.

Containerless preparation of advanced optical glasses: Experiment 77F095

NASA Technical Reports Server (NTRS)

Happe, R. A.; Kim, K. S.

1982-01-01

Containerless processing of optical glasses was studied in preparation for space shuttle MEA flight experiments. Ground based investigation, experiment/hardware coordination activities and development of flight experiment and sample characterization plans were investigated. In the ground based investigation over 100 candidate glass materials for space processing were screened and promising compositions were identified. The system of Nb2O5-TiO2-CaO was found to be very rich with containerless glass compositions and as extensive number of the oxides combinations were tried resulting in a glass formation ternary phase diagram. The frequent occurrence of glass formation by containerless processing among the compositions for which no glass formations were previously reported indicated the possibility and an advantage of containerless processing in a terrestrial environment.

Backbone N xH compounds at high pressures

DOE PAGES

Goncharov, Alexander F.; Holtgrewe, Nicholas; Qian, Guangrui; ...

2015-06-05

Optical and synchrotron x-ray diffraction diamond anvil cell experiments have been combined with first principles theoretical structure predictions to investigate mixtures of N 2 and H 2 up to 55 GPa. Our experiments show the formation of structurally complex van der Waals compounds above 10 GPa. However, we found that these N xH (0.52, H 2, and NH 3 above approximately 40 GPa. Lastly, our results suggest new pathways for synthesis of environmentally benign high energy-density materials. These materials could also exist as alternative planetary ices.

Fire safety in space - beyond flammability testing of small samples

NASA Astrophysics Data System (ADS)

Jomaas, Grunde; Torero, Jose L.; Eigenbrod, Christian; Niehaus, Justin; Olson, Sandra L.; Ferkul, Paul V.; Legros, Guillaume; Fernandez-Pello, A. Carlos; Cowlard, Adam J.; Rouvreau, Sebastien; Smirnov, Nickolay; Fujita, Osamu; T`ien, James S.; Ruff, Gary A.; Urban, David L.

2015-04-01

An international research team has been assembled to reduce the uncertainty and risk in the design of spacecraft fire safety systems by testing material samples in a series of flight experiments (Saffire 1, 2, and -3) to be conducted in an Orbital Science Corporation Cygnus vehicle after it has undocked from the International Space Station (ISS). The tests will be fully automated with the data downlinked at the conclusion of the test before the Cygnus vehicle re-enters the atmosphere. The unmanned, pressurized environment in the Saffire experiments allows for the largest sample sizes ever to be tested for material flammability in microgravity, which will be based on the characteristics of flame spread over the surface of the combustible material. Furthermore, the experiments will have a duration that is unmatched in scale compared to earth based microgravity research facilities such as drop towers (about 5 s) and parabolic flights (about 20 s). In contrast to sounding rockets, the experiments offer a much larger volume, and the reduction in the oxygen concentration during the Saffire experiments will be minimal. The selection of the experimental settings for the first three Saffire experiments has been based on existing knowledge of scenarios that are relevant, yet challenging, for a spacecraft environment. Given that there is always airflow in the space station, all the experiments are conducted with flame spread in either concurrent or opposed flow, though with the flow being stopped in some tests, to simulate the alarm mode environment in the ISS and thereby also to study extinguishment. The materials have been selected based on their known performance in NASA STD-6001Test-1, and with different materials being classified as charring, thermally thin, and thermally thick. Furthermore, materials with non-uniform surfaces will be investigated.

Numerical simulations of SHPB experiments for the dynamic compressive strength and failure of ceramics

NASA Astrophysics Data System (ADS)

Anderson, Charles E., Jr.; O'Donoghue, Padraic E.; Lankford, James; Walker, James D.

1992-06-01

Complementary to a study of the compressive strength of ceramic as a function of strain rate and confinement, numerical simulations of the split-Hopkinson pressure bar (SHPB) experiments have been performed using the two-dimensional wave propagation computer program HEMP. The numerical effort had two main thrusts. Firstly, the interpretation of the experimental data relies on several assumptions. The numerical simulations were used to investigate the validity of these assumptions. The second part of the effort focused on computing the idealized constitutive response of a ceramic within the SHPB experiment. These numerical results were then compared against experimental data. Idealized models examined included a perfectly elastic material, an elastic-perfectly plastic material, and an elastic material with failure. Post-failure material was modeled as having either no strength, or a strength proportional to the mean stress. The effects of confinement were also studied. Conclusions concerning the dynamic behavior of a ceramic up to and after failure are drawn from the numerical study.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Corona, Edmundo

The objective of this memo is to present a brief report of the progress achieved during FY2016 on the investigation of ductile failure in the 2013 Sandia Fracture Challenge specimen. It is a follow-up to the results of an experimental investigation presented in [1]. The experi- mental investigation was conducted with both the original steel A286 material used in the fracture challenge as well as with Al 7075-T651. The new results include further microscopy work for the steel A286 specimens, failure criterion veri cation for both materials and the implementation of a nite element model containing `material imperfections' to simulatemore » the limit load in the response of the steel A286 specimens. Funding used to conduct the work presented here was provided by the ASC V&V program on validation of shear failure (Benjamin Reedlunn, PI) and from Sandia's LDRD program. This memo assumes that the reader is familiar with the material in [1].« less

New developments in tribomechanical modeling of automotive sheet steel forming

NASA Astrophysics Data System (ADS)

Khandeparkar, Tushar; Chezan, Toni; van Beeck, Jeroen

2018-05-01

Forming of automotive sheet metal body panels is a complex process influenced by both the material properties and contact conditions in the forming tooling. Material properties are described by the material constitutive behavior and the material flow into the forming die can be described by the tribological system. This paper investigates the prediction accuracy of the forming process using the Tata Steel state of the art description of the material constitutive behavior in combination with different friction models. A cross-die experiment is used to investigate the accuracy of local deformation modes typically seen in automotive sheet metal forming operations. Results of advanced friction models as well as the classical Coulomb friction description are compared to the experimentally measured strain distribution and material draw-in. Two hot-dip galvanized coated steel forming grades were used for the investigations. The results show that the accuracy of the simulation is not guaranteed by the advanced friction models for the entire investigated blank holder force range, both globally and locally. A measurable difference between the calculated and measured local strains is seen for both studied models even in the case where the global indicator, i.e. the draw-in, is well predicted.

Rheological Investigation of Cryovolcanic Slurries

NASA Astrophysics Data System (ADS)

Morrison, A. A.; Whittington, A. G.; Zhong, F.; Mitchell, K. L.; Carey, E. M.

2018-06-01

Subliquidus rheological experiments will be conducted for briny cryovolcanic compositions. Understanding how these materials move, deform, and evolve upon crystallizing will help constrain what morphological features can form by various compositions.

Standard Methods for Unnotched Tension Testing of Textile Composites

NASA Technical Reports Server (NTRS)

Portanova, M. A.

1995-01-01

An investigation was conducted by researchers at the Boeing Defense & Space Group to investigate the effects of specimen sizing on several braided textile materials. Test results from this and other test programs were compared in an effort to determine what effect, if any, specimen size has on elastic property measurements of unnotched tension test. In general, the unnotched tensile strength of 2-D braids was found to be insensitive to specimen width, length, or thickness effects. The results from this study suggest that standard testing methods used for tape materials may be sufficient for tension testing of textile composite materials. Specifically, the straight sided specimen geometry described in ASTM 3034, and used by Boeing, should provide acceptable results. Further experiments performed at Boeing and by other investigators on other textile architectures suggest similar results. Although specimen size studies were not conducted, failing stresses varied on the same order as those obtained with the 2-D materials. This suggests that the accuracy of the results were consistent with those obtained with the 2-D materials.

Improved silicon nitride for advanced heat engines

NASA Technical Reports Server (NTRS)

Yeh, H. C.; Wimmer, J. M.

1986-01-01

Silicon nitride is a high temperature material currently under consideration for heat engine and other applications. The objective is to improve the net shape fabrication technology of Si3N4 by injection molding. This is to be accomplished by optimizing the process through a series of statistically designed matrix experiments. To provide input to the matrix experiments, a wide range of alternate materials and processing parameters was investigated throughout the whole program. The improvement in the processing is to be demonstrated by a 20 percent increase in strength and a 100 percent increase in the Weibull modulus over that of the baseline material. A full characterization of the baseline process was completed. Material properties were found to be highly dependent on each step of the process. Several important parameters identified thus far are the starting raw materials, sinter/hot isostatic pressing cycle, powder bed, mixing methods, and sintering aid levels.

Construction of a Digital Video Library: A Socio-Technical Pilot Study on College Students' Attitudes

ERIC Educational Resources Information Center

Chen, Hsin-Liang; Choi, Gilok

2005-01-01

This study investigates socio-technical aspects of digital video libraries based on college students' learning experiences and perspectives. Forty-one students in biology classes were studied through a survey and individual interviews. Findings are presented by the students' knowledge of computer technology, experiences with AV materials, and…

Figuring Home: The Role of Commodities in the Transnational Experience

ERIC Educational Resources Information Center

Penman, Christine; Omar, Maktoba

2011-01-01

This article proposes to investigate the role played by material goods in the transnational experience. Previous research has shown that the movement of people across the world comes with a corollary of cultural flows which find their expression in multiple ways. This article looks more specifically at the kind of commodities that international…

Quantum critical dynamics for a prototype class of insulating antiferromagnets

NASA Astrophysics Data System (ADS)

Wu, Jianda; Yang, Wang; Wu, Congjun; Si, Qimiao

2018-06-01

Quantum criticality is a fundamental organizing principle for studying strongly correlated systems. Nevertheless, understanding quantum critical dynamics at nonzero temperatures is a major challenge of condensed-matter physics due to the intricate interplay between quantum and thermal fluctuations. The recent experiments with the quantum spin dimer material TlCuCl3 provide an unprecedented opportunity to test the theories of quantum criticality. We investigate the nonzero-temperature quantum critical spin dynamics by employing an effective O (N ) field theory. The on-shell mass and the damping rate of quantum critical spin excitations as functions of temperature are calculated based on the renormalized coupling strength and are in excellent agreement with experiment observations. Their T lnT dependence is predicted to be dominant at very low temperatures, which will be tested in future experiments. Our work provides confidence that quantum criticality as a theoretical framework, which is being considered in so many different contexts of condensed-matter physics and beyond, is indeed grounded in materials and experiments accurately. It is also expected to motivate further experimental investigations on the applicability of the field theory to related quantum critical systems.

Machanics of Granular Materials (MGM) Investigator

NASA Technical Reports Server (NTRS)

2000-01-01

Key persornel in the Mechanics of Granular Materials (MGM) experiment include Khalid Alshibli, project scientist at NASA's Marshall Space Flight Center (MSFC). Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. MGM experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that cannot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. (Credit: MSFC).

[Clinical experience in osteoplastic material Allomatrix-implant and fibrin rich platelets use in surgical treatment of jaw radicular cysts].

PubMed

Kuz'minykh, I A

2009-01-01

Bones forming optimizators applying in surgical dentistry is an important element of jaw destructive processes successful treatment. Today use of osteoplastic materials on the collagen basis is widely spread. One of this challenge solution is FRP and Allomatrix-implant material applying to jaws during surgery operations. We described clinical investigation phase: the estimation of postoperative and remote results of treatment was carried out.

An Experiment in the Use of Programmed Materials in Teaching High School Biology.

ERIC Educational Resources Information Center

Young, Paul Alexander

Investigated were the feasibility and effectiveness of using programed materials with concomitant laboratory exercises in teaching genetics on the secondary level. Students from two white and two Negro high schools in the Atlantic Public School System participated, with one control and one experimental biology class in each school taught by the…

The Effect of Delayed-JOLs and Sentence Generation on Children's Monitoring Accuracy and Regulation of Idiom Study

ERIC Educational Resources Information Center

van Loon, Mariëtte H.; de Bruin, Anique B. H.; van Gog, Tamara; van Merriënboer, Jeroen J. G.

2013-01-01

When studying verbal materials, both adults and children are often poor at accurately monitoring their level of learning and regulating their subsequent restudy of materials, which leads to suboptimal test performance. The present experiment investigated how monitoring accuracy and regulation of study could be improved when learning idiomatic…

Impact fracture toughness evaluation for high-density polyethylene materials

NASA Astrophysics Data System (ADS)

Cherief, M. N. D.; Elmeguenni, M.; Benguediab, M.

2017-03-01

The impact fracture behavior of a high-density polyethylene (HDPE) material is investigated experimentally and theoretically. Single-edge notched bending (SENB) specimens are tested in experiments with three-point bending and in the Charpy impact tests. An energy model is proposed for evaluating the HDPE impact toughness, which provides a description of both brittle and ductile fracture.

Radiology/Imaging. Clinical Rotation. Instructor's Packet and Student Study Packet.

ERIC Educational Resources Information Center

Texas Univ., Austin. Extension Instruction and Materials Center.

The instructor's packet, the first of two packets, is one of a series of materials designed to help students who are investigating the activities within a radiology department or considering any of the imaging technologies as a career. The material is designed to relate training experience to information studied in the classroom. This packet…

Experiments with the low melting indium-bismuth alloy system

NASA Technical Reports Server (NTRS)

Krepski, Richard P.

1992-01-01

The following is a laboratory experiment designed to create an interest in and to further understanding of materials science. The primary audience for this material is the junior high school or middle school science student having no previous familiarity with the material, other than some knowledge of temperature and the concepts of atoms, elements, compounds, and chemical reactions. The objective of the experiment is to investigate the indium-bismuth alloy system. Near the eutectic composition, the liquidus is well below the boiling point of water, allowing simple, minimal hazard casting experiments. Such phenomena as metal oxidation, formation of intermetallic compound crystals, and an unusual volume increase during solidification could all be directly observed. A key concept for students to absorb is that properties of an alloy (melting point, mechanical behavior) may not correlate with simple interpolation of properties of the pure components. Discussion of other low melting metals and alloys leads to consideration of environmental and toxicity issues, as well as providing some historical context. Wetting behavior can also be explored.

Recall and recognition hypermnesia for Socratic stimuli.

PubMed

Kazén, Miguel; Solís-Macías, Víctor M

2016-01-01

In two experiments, we investigate hypermnesia, net memory improvements with repeated testing of the same material after a single study trial. In the first experiment, we found hypermnesia across three trials for the recall of word solutions to Socratic stimuli (dictionary-like definitions of concepts) replicating Erdelyi, Buschke, and Finkelstein and, for the first time using these materials, for their recognition. In the second experiment, we had two "yes/no" recognition groups, a Socratic stimuli group presented with concrete and abstract verbal materials and a word-only control group. Using signal detection measures, we found hypermnesia for concrete Socratic stimuli-and stable performance for abstract stimuli across three recognition tests. The control group showed memory decrements across tests. We interpret these findings with the alternative retrieval pathways (ARP) hypothesis, contrasting it with alternative theories of hypermnesia, such as depth of processing, generation and retrieve-recognise. We conclude that recognition hypermnesia for concrete Socratic stimuli is a reliable phenomenon, which we found in two experiments involving both forced-choice and yes/no recognition procedures.

Microfluidic Investigation of Oil Mobilization in Shale Fracture Networks at Reservoir Conditions

NASA Astrophysics Data System (ADS)

Porter, M. L.; Jimenez-Martinez, J.; Carey, J. W.; Viswanathan, H. S.

2015-12-01

Investigations of pore-scale fluid flow and transport phenomena using engineered micromodels has steadily increased in recent years. In these investigations fluid flow is restricted to two-dimensions allowing for real time visualization and quantification of complex flow and reactive transport behavior, which is difficult to obtain in other experimental systems. One drawback to these studies is the use of engineered materials that do not faithfully represent the rock properties (e.g., porosity, wettability, roughness, etc.) encountered in subsurface formations. In this work, we describe a unique high pressure (up to 1500 psi) and temperature (up to 80 °C) microfluidics experimental system in which we investigate fluid flow and transport in geo-material (e.g., shale, Portland cement, etc.) micromodels. The use of geo-material micromodels allows us to better represent fluid-rock interactions including wettability, chemical reactivity, and nano-scale porosity at conditions representative of natural subsurface environments. Here, we present experimental results in fracture systems with applications to hydrocarbon mobility in hydraulically fractured shale. Complex fracture network patterns are derived from 3D x-ray tomography images of actual fractures created in shale rock cores. We use both shale and glass micromodels, allowing for a detailed comparison between flow phenomena in the different materials. We discuss results from two-phase huff-and-puff experiments involving N2 and n-Decane, as well as three-phase displacement experiments involving supercritical CO2, brine, and n-Decane.

Liability of Science Educators for Laboratory Safety. NSTA Position Statement

ERIC Educational Resources Information Center

National Science Teachers Association (NJ1), 2007

2007-01-01

Laboratory investigations are essential for the effective teaching and learning of science. A school laboratory investigation ("lab") is an experience in the laboratory, classroom, or the field that provides students with opportunities to interact directly with natural phenomena or with data collected by others using tools, materials, data…

Physics-Based Simulation and Experiment on Blast Protection of Infill Walls and Sandwich Composites Using New Generation of Nano Particle Reinforced Materials

NASA Astrophysics Data System (ADS)

Irshidat, Mohammad

A critical issue for the development of nanotechnology is our ability to understand, model, and simulate the behavior of small structures and to make the connection between nano structure properties and their macroscopic functions. Material modeling and simulation helps to understand the process, to set the objectives that could guide laboratory efforts, and to control material structures, properties, and processes at physical implementation. These capabilities are vital to engineering design at the component and systems level. In this research, experimental-computational-analytical program was employed to investigate the performance of the new generation of polymeric nano-composite materials, like nano-particle reinforced elastomeric materials (NPREM), for the protection of masonry structures against blast loads. New design tools for using these kinds of materials to protect Infill Walls (e.g. masonry walls) against blast loading were established. These tools were also extended to cover other type of panels like sandwich composites. This investigation revealed that polymeric nano composite materials are strain rate sensitive and have large amount of voids distributed randomly inside the materials. Results from blast experiments showed increase in ultimate flexural resistance achieved by both unreinforced and nano reinforced polyurea retrofit systems applied to infill masonry walls. It was also observed that a thin elastomeric coating on the interior face of the walls could be effective at minimizing the fragmentation resulting from blast. More conclusions are provided with recommended future research.

Drop Tower Facility at Queensland University of Technology

NASA Astrophysics Data System (ADS)

Plagens, Owen; Castillo, Martin; Steinberg, Theodore; Ong, Teng-Cheong

The Queensland University of Technology (QUT) Drop Tower Facility is a {raise.17exscriptstyle˜}2.1 second, 21.3 m fall, dual capsule drop tower system. The dual capsule comprises of an uncoupled exterior hollow drag shield that experiences drag by the ambient atmosphere with the experimental capsule falling within the drag shield. The dual capsule system is lifted to the top of the drop tower via a mechanical crane and the dropping process is initiated by the cutting of a wire coupling the experimental package and suspending the drag shield. The internal experimental capsule reaches the bottom of the drag shield floor just prior to the deceleration stage at the air bag and during this time experience gravity levels of {raise.17exscriptstyle˜}10textsuperscript{-6} g. The deceleration system utilizes an inflatable airbag where experimental packages can be designed to experience a maximum deceleration of {raise.17exscriptstyle˜}10textsuperscript{18} g for {raise.17exscriptstyle˜}0.1 seconds. The drag shield can house experimental packages with a maximum diameter of 0.8 m and height of 0.9 m. The drag shield can also be used in foam mode, where the walls are lined with foam and small experiments can be dropped completely untethered. This mode is generally used for the study of microsatellite manipulation. Payloads can be powered by on-board power systems with power delivered to the experiment until free fall occurs. Experimental data that can be collected includes but is not limited to video, temperature, pressure, voltage/current from the power supply, and triggering mechanisms outputs which are simultaneously collected via data logging systems and high speed video recording systems. Academic and commercial projects are currently under investigation at the QUT Drop Tower Facility and collaboration is openly welcome at this facility. Current research includes the study of heterogeneously burning metals in oxygen which is aimed at fire safety applications and identifying size distributions and morphologies of particles produced during the combustion of bulk metals. Materials produced via self-propagating high-temperature synthesis in microgravity are investigated to produce high electroluminescent materials and high efficient dye sensitized electrolyte materials. The rapid cooling and quenching of ZBLAN glass in a microgravity environment is studied to reduce crystallization in the glass. Convective pool boiling and nucleate bubble formation in nano-fluids is aimed at investigating heat transfer properties in these new materials which are masked by gravity. Novel carbon nanotubes are produced in low gravity via an arch discharge to investigate the formation mechanisms of these materials.

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.

Toward Understanding Pore Formation And Mobility During Controlled Directional Solidification In A Microgravity Environment Investigation (PFMI)

NASA Technical Reports Server (NTRS)

Grugel, R. N.; Anilkumar, A.; Luz, P.; Jeter, L.; Volz, M. P.; Spivey, R.; Smith, G. A.; Curreri, Peter A. (Technical Monitor)

2002-01-01

The generation and inclusion of detrimental porosity, e.g., "pipes" and "rattails" can occur during controlled directional solidification processing. The origin of these defects is generally attributed to gas evolution and entrapment during solidification of the melt. On Earth, owing to buoyancy, an initiated bubble can rapidly rise through the liquid melt and "pop" at the surface; this is obviously not ensured in a low gravity or microgravity environment. Clearly, porosity generation and inclusion is detrimental to conducting any meaningful solidification-science studies in microgravity. Thus it is essential that model experiments be conducted in microgravity, to understand the details of the generation and mobility of porosity, so that methods can be found to eliminate it. In hindsight, this is particularly relevant given the results of the previous directional solidification experiments conducted in Space. The current International Space Station (ISS) Microgravity Science Glovebox (MSG) investigation addresses the central issue of porosity formation and mobility during controlled directional solidification processing in microgravity. The study will be done using a transparent metal-analogue material, succinonitrile (SCN) and succinonitrile-water "alloys", so that direct observation and recording of pore generation and mobility can be made during the experiments. Succinonitrile is particularly well suited for the proposed investigation because it is transparent, it solidifies in a manner analogous to most metals, it has a convenient melting point, its material properties are well characterized and, it has been successfully used in previous microgravity experiments. The PFMI experiment will be launched on the UF-2, STS-111 flight. Highlighting the porosity development problem in metal alloys during microgravity processing, the poster will describe: (i) the intent of the proposed experiments, (ii) the theoretical rationale behind using SCN as the study material for porosity generation and migration and, (iii) the experimental protocol for the investigation of the effects of the processing parameters. Photographs of the flight experimental hardware, and the novel sample ampoule, will be exhibited. The experimental apparatus will be described in detail and a summary of the scientific objectives will be presented.

Toward Understanding Pore Formation and Mobility during Controlled Directional Solidification in a Microgravity Environment Investigation (PFMI)

NASA Technical Reports Server (NTRS)

Grugel, Richard N.; Anilkumar, A. V.; Luz, Paul; Jeter, Linda; Volz, Martin P.; Spivey, Reggie; Smith, G.

2003-01-01

The generation and inclusion of detrimental porosity, e.g., pipes and rattails can occur during controlled directional solidification processing. The origin of these defects is generally attributed to gas evolution and entrapment during solidification of the melt. On Earth, owing to buoyancy, an initiated bubble can rapidly rise through the liquid melt and pop at the surface; this is obviously not ensured in a low gravity or microgravity environment. Clearly, porosity generation and inclusion is detrimental to conducting any meaningful solidification-science studies in microgravity. Thus it is essential that model experiments be conducted in microgravity, to understand the details of the generation and mobility of porosity, so that methods can be found to eliminate it. In hindsight, this is particularly relevant given the results of the previous directional solidification experiments conducted in Space. The current International Space Station (ISS) Microgravity Science Glovebox (MSG) investigation addresses the central issue of porosity formation and mobility during controlled directional solidification processing in microgravity. The study will be done using a transparent metal-analogue material, succinonitrile (SCN) and succinonitrile-water 'alloys', so that direct observation and recording of pore generation and mobility can be made during the experiments. Succinonitrile is particularly well suited for the proposed investigation because it is transparent, it solidifies in a manner analogous to most metals, it has a convenient melting point, its material properties are well characterized and, it has been successfully used in previous microgravity experiments. The PFMI experiment will be launched on the UF-2, STS-111 flight. Highlighting the porosity development problem in metal alloys during microgravity processing, the poster will describe: (i) the intent of the proposed experiments, (ii) the theoretical rationale behind using SCN as the study material for porosity generation and migration and, (iii) the experimental protocol for the investigation of the effects of the processing parameters. Photographs of the flight experimental hardware, and the novel sample ampoule, will be exhibited. The experimental apparatus will be described in detail and a summary of the scientific objectives will be presented.

Proposed pushered single shell capsule design for the investigation of mid/high Z mix on the NIF

NASA Astrophysics Data System (ADS)

Sacks, Ryan; Tipton, Robert; Graziani, Frank

2016-05-01

The CD Mix campaign has given a detailed explination of the mix mechanics in the current ignition capsule designs by investigating the relationship between material mixing, shell-fuel interfaces, and the change in thermonuclear yield given a deuterated layer in the capsule. Alternative ignition scenarios include the use of double shell designs that incorporate high-Z material in the capsule. Simulations are conducted on a proposed capsule platform using the ARES code on a scaled capsule design using a partially reduced glass capsule design. This allows for the inclusion of deuterium on the inner surface of the pusher layer similar to the CD mix experiments. The presence of silicon dioxide allows for the investigation of the influence of higher Z material on the mixing characteristics.

Machinability of some dentin simulating materials.

PubMed

Möllersten, L

1985-01-01

Machinability in low speed drilling was investigated for pure aluminium, Frasaco teeth, ivory, plexiglass and human dentin. The investigation was performed in order to find a suitable test material for drilling experiments using paralleling instruments. A material simulating human dentin in terms of cuttability at low drilling speeds was sought. Tests were performed using a specially designed apparatus. Holes to a depth of 2 mm were drilled with a twist drill using a constant feeding force. The time required was registered. The machinability of the materials tested was determined by direct comparison of the drilling times. As regards cuttability, first aluminium and then ivory were found to resemble human dentin most closely. By comparing drilling time variances the homogeneity of the materials tested was estimated. Aluminium, Frasaco teeth and plexiglass demonstrated better homogeneity than ivory and human dentin.

The study of excited oxygen molecule gas species production and quenching on thermal protection system materials

NASA Technical Reports Server (NTRS)

Nordine, Paul C.; Fujimoto, Gordon T.; Greene, Frank T.

1987-01-01

The detection of excited oxygen and ozone molecules formed by surface catalyzed oxygen atom recombination and reaction was investigated by laser induced fluorescence (LIF), molecular beam mass spectrometric (MBMS), and field ionization (FI) techniques. The experiment used partially dissociated oxygen flows from a microwave discharge at pressures in the range from 60 to 400 Pa or from an inductively coupled RF discharge at atmospheric pressure. The catalyst materials investigated were nickel and the reaction cured glass coating used for Space Shuttle reusable surface insulation tiles. Nonradiative loss processes for the laser excited states makes LIF detection of O2 difficult such that formation of excited oxygen molecules could not be detected in the flow from the microwave discharge or in the gaseous products of atom loss on nickel. MBMS experiments showed that ozone was a product of heterogeneous O atom loss on nickel and tile surfaces at low temperatures and that ozone is lost on these materials at elevated temperatures. FI was separately investigated as a method by which excited oxygen molecules may be conveniently detected. Partial O2 dissociation decreases the current produced by FI of the gas.

The disfluent discourse: Effects of filled pauses on recall

PubMed Central

Fraundorf, Scott H.; Watson, Duane G.

2011-01-01

We investigated the mechanisms by which fillers, such as uh and um, affect memory for discourse. Participants listened to and attempted to recall recorded passages adapted from Alice’s Adventures in Wonderland. The type and location of interruptions were manipulated through digital splicing. In Experiment 1, we tested a processing time account of fillers’ effects. While fillers facilitated recall, coughs matched in duration to the fillers impaired recall, suggesting that fillers’ benefits cannot be attributed to adding processing time. In Experiment 2, fillers’ locations were manipulated based on norming data to be either predictive or non-predictive of upcoming material. Fillers facilitated recall in both cases, inconsistent with an account in which listeners predict upcoming material using past experience with the distribution of fillers. Instead, these results suggest an attentional orienting account in which fillers direct attention to the speech stream but do not always result in specific predictions about upcoming material. PMID:21765590

Damping Experiment of Spinning Composite Plates with Embedded Viscoelastic Material

NASA Technical Reports Server (NTRS)

Mehmed, Oral; Kosmatka, John B.

1997-01-01

One way to increase gas turbine engine blade reliability and durability is to reduce blade vibration. It is well known that vibration reduction can be achieved by adding damping to metal and composite blade-disk systems. This experiment was done to investigate the use of integral viscoelastic damping treatments to reduce vibration of rotating composite fan blades. It is part of a joint research effort with NASA LeRC and the University of California, San Diego (UCSD). Previous vibration bench test results obtained at UCSD show that plates with embedded viscoelastic material had over ten times greater damping than similar untreated plates; and this was without a noticeable change in blade stiffness. The objectives of this experiment, were to verify the structural integrity of composite plates with viscoelastic material embedded between composite layers while under large steady forces from spinning, and to measure the damping and natural frequency variation with rotational speed.

Experimental Equipment Design and Fabrication Study for Delta-G Experiment

NASA Technical Reports Server (NTRS)

1997-01-01

The Research Machine Shop at UAH did not develop any new technology in the performance of the following tasks. All tasks were performed as specified.UAH RMS shall design and fabricate a "poor" model of a silicon-carbide high-temperature crucible with dimensions of 8 inches in diameter and 4 inches high-temperature crucible for pouring liquid ceramic materials at 1200 C into molds from heating ovens. The crucible shall also be designed with a manipulation fixture to facilitate holding and pouring of the heated liquid material. UAH RMS shall investigate the availability of 400 Hz, high-current (65 volts @ 100 amperes) power systems for use in high-speed rotating disk experiments, UAH RMS shall investigate, develop a methodology, and experiment on the application of filament-wound carbon fibers to the periphery of ceramic superconductors to withstand high levels of rotational g-forces. UAH RMS shall provide analytical data to verify the resulting improved disc with carbon composite fibers.

Experimental investigation on phase change materials as heating element for non-electric neonatal incubator

NASA Astrophysics Data System (ADS)

Matahari, Rho Natta; Putra, Nandy; Ariantara, Bambang; Amin, Muhammad; Prawiro, Erwin

2017-02-01

High number of preterm births is one of the issues in improving health standard. The effort to help premature babies is hampered by high cost of NICU care in hospital. In addition, uneven distribution of electricity to remote area made it hard to operate the incubator. Utilization of phase change material beeswax to non-electricity incubator as heating element becomes alternative option to save premature babies. The objective of this experiment is to investigate the most efficient mass of beeswax according to Indonesian National Standard to earn over time and ideal temperature of incubator. Experiment was performed using prototype incubator, which utilizes natural convection phenomenon in the heating process of incubator. Utilization of fin is to accelerate heat distribution in the incubator. Result of experiment showed that the most efficient mass of PCM is 3 kg, which has 2.45 hours of running time for maintaining temperature of incubator in range of 32-36 °C.

The LDCE Particle Impact Experiment as flown on STS-46. [limited duration space environment candidate materials exposure (LDCE)

NASA Technical Reports Server (NTRS)

Maag, Carl R.; Tanner, William G.; Borg, Janet; Bibring, Jean-Pierre; Alexander, W. Merle; Maag, Andrew J.

1992-01-01

Many materials and techniques have been developed by the authors to sample the flux of particles in Low Earth Orbit (LEO). Though regular in-site sampling of the flux in LEO the materials and techniques have produced data which compliment the data now being amassed by the Long Duration Exposure Facility (LDEF) research activities. Orbital debris models have not been able to describe the flux of particles with d sub p less than or = 0.05 cm, because of the lack of data. Even though LDEF will provide a much needed baseline flux measurement, the continuous monitoring of micron and sub-micron size particles must be carried out. A flight experiment was conducted on the Space Shuttle as part of the LDCE payload to develop an understanding of the Spatial Density (concentration) as a function of size (mass) for particle sizes 1 x 10(exp 6) cm and larger. In addition to the enumeration of particle impacts, it is the intent of the experiment that hypervelocity particles be captured and returned intact. Measurements will be performed post flight to determine the flux density, diameters, and subsequent effects on various optical, thermal control and structural materials. In addition to these principal measurements, the Particle Impact Experiment (PIE) also provides a structure and sample holders for the exposure of passive material samples to the space environment, e.g., thermal cycling, and atomic oxygen, etc. The experiment will measure the optical property changes of mirrors and will provide the fluence of the ambient atomic oxygen environment to other payload experimenters. In order to augment the amount of material returned in a form which can be analyzed, the survivability of the experiment as well as the captured particles will be assessed. Using Sandia National Laboratory's hydrodynamic computer code CTH, hypervelocity impacts on the materials which comprise the experiments have been investigated and the progress of these studies are reported.

Surface physics-materials science research possibilities on a lunar base

NASA Astrophysics Data System (ADS)

Ignatiev, A.

1990-03-01

The benefits of experimental investigations are discussed in terms of the vacuum environment and low-gravity conditions which can be made possible by a lunar base. The proposed experiments address the interaction of UV and cosmic radiation with the atomic surfaces and bulk properties of materials, the study of microclusters, and the development of epitaxial films in a lunar environment. The interaction of low- and high-energy charged particles and radiation with materials can potentially be studied to analyze the use of the materials in space.

The space shuttle payload planning working groups: Volume 9: Materials processing and space manufacturing

NASA Technical Reports Server (NTRS)

1973-01-01

The findings and recommendations of the Materials Processing and Space Manufacturing group of the space shuttle payload planning activity are presented. The effects of weightlessness on the levitation processes, mixture stability, and control over heat and mass transport in fluids are considered for investigation. The research and development projects include: (1) metallurgical processes, (2) electronic materials, (3) biological applications, and (4)nonmetallic materials and processes. Additional recommendations are provided concerning the allocation of payload space, acceptance of experiments for flight, flight qualification, and private use of the space shuttle.

Understanding materials behavior from atomistic simulations: Case study of al-containing high entropy alloys and thermally grown aluminum oxide

NASA Astrophysics Data System (ADS)

Yinkai Lei

Atomistic simulation refers to a set of simulation methods that model the materials on the atomistic scale. These simulation methods are faster and cheaper alternative approaches to investigate thermodynamics and kinetics of materials compared to experiments. In this dissertation, atomistic simulation methods have been used to study the thermodynamic and kinetic properties of two material systems, i.e. the entropy of Al-containing high entropy alloys (HEAs) and the vacancy migration energy of thermally grown aluminum oxide. (Abstract shortened by ProQuest.).

Experimental and numerical characterization of expanded glass granules

NASA Astrophysics Data System (ADS)

Chaudry, Mohsin Ali; Woitzik, Christian; Düster, Alexander; Wriggers, Peter

2018-07-01

In this paper, the material response of expanded glass granules at different scales and under different boundary conditions is investigated. At grain scale, single particle tests can be used to determine properties like Young's modulus or crushing strength. With experiments like triaxial and oedometer tests, it is possible to examine the bulk mechanical behaviour of the granular material. Our experimental investigation is complemented by a numerical simulation where the discrete element method is used to compute the mechanical behaviour of such materials. In order to improve the simulation quality, effects such as rolling resistance, inelastic behaviour, damage, and crushing are also included in the discrete element method. Furthermore, the variation of the material properties of granules is modelled by a statistical distribution and included in our numerical simulation.

Gradient Plasticity Model and its Implementation into MARMOT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barker, Erin I.; Li, Dongsheng; Zbib, Hussein M.

2013-08-01

The influence of strain gradient on deformation behavior of nuclear structural materials, such as boby centered cubic (bcc) iron alloys has been investigated. We have developed and implemented a dislocation based strain gradient crystal plasticity material model. A mesoscale crystal plasticity model for inelastic deformation of metallic material, bcc steel, has been developed and implemented numerically. Continuum Dislocation Dynamics (CDD) with a novel constitutive law based on dislocation density evolution mechanisms was developed to investigate the deformation behaviors of single crystals, as well as polycrystalline materials by coupling CDD and crystal plasticity (CP). The dislocation density evolution law in thismore » model is mechanism-based, with parameters measured from experiments or simulated with lower-length scale models, not an empirical law with parameters back-fitted from the flow curves.« less

When does prior knowledge disproportionately benefit older adults’ memory?

PubMed Central

Badham, Stephen P.; Hay, Mhairi; Foxon, Natasha; Kaur, Kiran; Maylor, Elizabeth A.

2016-01-01

ABSTRACT Material consistent with knowledge/experience is generally more memorable than material inconsistent with knowledge/experience – an effect that can be more extreme in older adults. Four experiments investigated knowledge effects on memory with young and older adults. Memory for familiar and unfamiliar proverbs (Experiment 1) and for common and uncommon scenes (Experiment 2) showed similar knowledge effects across age groups. Memory for person-consistent and person-neutral actions (Experiment 3) showed a greater benefit of prior knowledge in older adults. For cued recall of related and unrelated word pairs (Experiment 4), older adults benefited more from prior knowledge only when it provided uniquely useful additional information beyond the episodic association itself. The current data and literature suggest that prior knowledge has the age-dissociable mnemonic properties of (1) improving memory for the episodes themselves (age invariant), and (2) providing conceptual information about the tasks/stimuli extrinsically to the actual episodic memory (particularly aiding older adults). PMID:26473767

The microgravity environment of the D1 mission

NASA Technical Reports Server (NTRS)

Hamacher, H.; Merbold, U.; Jilg, R.

1990-01-01

Some characteristic features and results of D1 microgravity measurements are discussed as performed in the Material Science Double Rack (MSDR) and the Materials Science Double Rack for Experiment Modules and Apparatus (MEDEA). Starting with a brief review of the main potential disturbances, the payload aspects of interest to the analysis and the accelerometer measuring systems are described. The microgravity data are analyzed with respect to selected mission events such as thruster firings for attitude control, operations of Spacelab experiment facilities, vestibular experiments and crew activities. The origins are divided into orbit, vehicle, and experiment induced perturbations. It has been found that the microgravity-environment is dictated mainly by payload-induced perturbations. To reduce the microgravity-level, the design of some experiment facilities has to be improved by minimizing the number of moving parts, decoupling of disturbing units from experiment facilities, by taking damping measures, etc. In addition, strongly disturbing experiments and very sensitive investigations should be performed in separate mission phases.

Informing a Pedagogy for Design and Problem-Solving in Hard Materials by Theorising Technologists' Learning Experiences

ERIC Educational Resources Information Center

Potter, Patricia; France, Bev

2018-01-01

Design and problem solving are central to technology and have distinguished learning in technology from other curriculum areas. This research investigated how expert technologists learn design and problem solving through experience. Data was collected from four expert technologists and this information was analysed using learning theories that…

To Tan or Not to Tan?: Students Learn About Sunscreens through an Inquiry Activity Based on the Learning Cycle

ERIC Educational Resources Information Center

Keen-Rocha, Linda

2005-01-01

Science instructors sometimes avoid inquiry-based activities due to limited classroom time. Inquiry takes time, as students choose problems, design experiments, obtain materials, conduct investigations, gather data, communicate results, and discuss their experiments. While there are no quick solutions to time concerns, the 5E learning cycle seeks…

The Radiative Decay of Green and Red Photoluminescent Phosphors: An Undergraduate Kinetics Experiment for Materials Chemistry

ERIC Educational Resources Information Center

Esposti, C. Degli; Bizzocchi, L.

2008-01-01

This article describes a laboratory experiment that allows the students to investigate the radiative properties of the green and red emitting phosphors that are employed in commercial fluorescent lamps. Making use of a spectrofluorometer, students first record the emission spectrum of a fluorescent lamp under normal operating conditions, and then…

The Impact of Learning Styles on Achievement in Principles of Microeconomics: A Natural Experiment

ERIC Educational Resources Information Center

Terregrossa, Ralph; Englander, Fred; Englander, Valerie

2009-01-01

This study investigates how a natural experiment occurring in the teaching of principles of microeconomics allows a test of the Dunn and Dunn learning styles model (Dunn & Griggs, 2000). The material for the first exam, based on essential definitions and theoretical foundations, was taught in a conventional, inductive style, more compatible with…

Effect of Two-Tier Diagnostic Tests on Promoting Learners' Conceptual Understanding of Variables in Conducting Scientific Experiments

ERIC Educational Resources Information Center

Çil, Emine

2015-01-01

Taking a test generally improves the retention of the material tested. This is a phenomenon commonly referred to as testing effect. The present research investigated whether two-tier diagnostic tests promoted student teachers' conceptual understanding of variables in conducting scientific experiments, which is a scientific process skill. In this…

Spacing and Induction: Application to Exemplars Presented as Auditory and Visual Text

ERIC Educational Resources Information Center

Zulkiply, Norehan; McLean, John; Burt, Jennifer S.; Bath, Debra

2012-01-01

It is an established finding that spacing repetitions generally facilitates memory for the repeated events. However, the effect of spacing of exemplars on inductive learning is not really known. Two experiments using textual material were conducted to investigate the effect of spacing on induction. Experiment 1 and 2 extended the generality of…

Materials of the final reports on the joint Soviet-American experiment on the Kosmos-936 biosatellite

NASA Technical Reports Server (NTRS)

Timofeyev-Resolskiy, N. V.; Parfenov, G. P.; Tairbekov, M.; Platonova, R. N.; Rostopshina, A. V.; Zhvalikovskaya, V. P.; Mosgovaya, I. Y.; Shvets, V. N.; Kovalev, Y. Y.; Dudkin, V. Y.

1978-01-01

Biological experiments onboard the Kosmos-936 investigated the effect of weightlessness on the basic components of cells, the genetic structure and energy apparatus. Genetic studies were made on the Drosophila melanogaster. Experiments were made on higher vegetation and fungi as well. The results indicate that weightlessness cannot be the principal barrier for normal development. An experiment with ectopic osteogenesis in weightlessness was carried out. Measurements were made of cosmic radiation inside and outside the biosatellite.

Carbon Nanotubes for Human Space Flight

NASA Technical Reports Server (NTRS)

Scott, Carl D.; Files, Brad; Yowell, Leonard

2003-01-01

Single-wall carbon nanotubes offer the promise of a new class of revolutionary materials for space applications. The Carbon Nanotube Project at NASA Johnson Space Center has been actively researching this new technology by investigating nanotube production methods (arc, laser, and HiPCO) and gaining a comprehensive understanding of raw and purified material using a wide range of characterization techniques. After production and purification, single wall carbon nanotubes are processed into composites for the enhancement of mechanical, electrical, and thermal properties. This "cradle-to-grave" approach to nanotube composites has given our team unique insights into the impact of post-production processing and dispersion on the resulting material properties. We are applying our experience and lessons-learned to developing new approaches toward nanotube material characterization, structural composite fabrication, and are also making advances in developing thermal management materials and electrically conductive materials in various polymer-nanotube systems. Some initial work has also been conducted with the goal of using carbon nanotubes in the creation of new ceramic materials for high temperature applications in thermal protection systems. Human space flight applications such as advanced life support and fuel cell technologies are also being investigated. This discussion will focus on the variety of applications under investigation.

Evaluation of adhesive materials used on the Long Duration Exposure Facility. Report, October 1989-January 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dursch, H.W.; Keough, B.K.; Pippin, H.G.

1995-03-01

The adhesive and adhesive-like materials flown on LDEF included epoxies and silicones (including lap shear specimens), conformal coatings, potting compounds, and several tapes and transfer films. With the exception of the lap shear specimens, these materials were used in the fabrication and assembly of the experiments such as bonding thermal control surfaces to other hardware and holding individual specimens in place, similar to applications on other spacecraft. Typically, the adhesives were not exposed to solar radiation or atomic oxygen. Only one adhesive system was used in a structural application. This report documents all results of the Materials and Systems SIGmore » investigation into the effect of long term low Earth orbit (LEO) exposure of these materials. Results of this investigation show that if the material was shielded from exposure to LDEF`s external environment, the 69 month exposure to LEO had, in most cases, minimal effect on the material.« less

Computational Proficiency and Algorithmic Learning of Sixth-Graders Using DMP Materials: A Formative Evaluation. Technical Report No. 401.

ERIC Educational Resources Information Center

Wiles, Clyde

Two questions were investigated in this study: (1) How did the computational proficiency of sixth graders who had one year's experience with Developing Mathematical Processes (DMP) materials compare with an equivalent group of students who used the usual textbook program; and (2) What occurs when sixth graders study algorithms as sequences of rule…

Very high temperature behavior of HTGR core materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soo, P.; Uneberg, G.; Sabatini, R.

1978-01-01

A description is given of experiments to investigate the behavior of HTGR core materials during hypothetical heatup accidents in which the core temperature is assumed to reach values between 2400/sup 0/C and the graphite sublimation range (>3600/sup 0/C). The work includes BISO coated fuel particle failure, simulated fission product migration in core graphite, and graphite sublimation behavior.

Investigations on injection molded, glass-fiber reinforced polyamide 6 integral foams using breathing mold technology

NASA Astrophysics Data System (ADS)

Roch, A.; Kehret, L.; Huber, T.; Henning, F.; Elsner, P.

2015-05-01

Investigations on PA6-GF50 integral foams have been carried out using different material systems: longfiber- and shortfiber-reinforced PA6 as well as unreinforced PA6 as a reference material. Both chemical and physical blowing agents were applied. Breathing mold technology (decompression of the mold) was selected for the foaming process. The integral foam design, which can be conceived as a sandwich structure, helps to save material in the neutral axis area and maintains a distance between load-bearing, unfoamed skin layers. For all test series an initial mold gap of 2.5 mm was chosen and the same amount of material was injected. In order to realize different density reductions, the mold opening stroke was varied. The experiments showed that, at a constant mass per unit area, integral polyamide 6 foams have a significantly higher bending stiffness than compact components, due to their higher area moment of inertia after foaming. At a constant surface weight the bending stiffness in these experiments could be increased by up to 600 %. Both shortfiber- and longfiber-reinforced polyamide 6 showed an increase in energy absorption during foaming.

Investigating the Modality and Redundancy Effects for Learners with Persistent Pain

ERIC Educational Resources Information Center

Smith, Alexander; Ayres, Paul

2016-01-01

Two experiments were conducted to investigate how individuals with persistent pain would respond to instructional materials designed to promote the modality and redundancy effects. It was predicted that persistent pain would reduce the positive impact of narrated text due to reduced working memory capacity. One hundred thirty-seven full-time…

Elastic Cherenkov effects in transversely isotropic soft materials-I: Theoretical analysis, simulations and inverse method

NASA Astrophysics Data System (ADS)

Li, Guo-Yang; Zheng, Yang; Liu, Yanlin; Destrade, Michel; Cao, Yanping

2016-11-01

A body force concentrated at a point and moving at a high speed can induce shear-wave Mach cones in dusty-plasma crystals or soft materials, as observed experimentally and named the elastic Cherenkov effect (ECE). The ECE in soft materials forms the basis of the supersonic shear imaging (SSI) technique, an ultrasound-based dynamic elastography method applied in clinics in recent years. Previous studies on the ECE in soft materials have focused on isotropic material models. In this paper, we investigate the existence and key features of the ECE in anisotropic soft media, by using both theoretical analysis and finite element (FE) simulations, and we apply the results to the non-invasive and non-destructive characterization of biological soft tissues. We also theoretically study the characteristics of the shear waves induced in a deformed hyperelastic anisotropic soft material by a source moving with high speed, considering that contact between the ultrasound probe and the soft tissue may lead to finite deformation. On the basis of our theoretical analysis and numerical simulations, we propose an inverse approach to infer both the anisotropic and hyperelastic parameters of incompressible transversely isotropic (TI) soft materials. Finally, we investigate the properties of the solutions to the inverse problem by deriving the condition numbers in analytical form and performing numerical experiments. In Part II of the paper, both ex vivo and in vivo experiments are conducted to demonstrate the applicability of the inverse method in practical use.

Are There Feasible Alternatives to Laboratory Animals?

ERIC Educational Resources Information Center

Rowan, A. N.

1976-01-01

Discusses several alternatives to the use of laboratory animals in investigating biomedical problems. Alternatives include tissue culture, use of plant and bacterial material, redesigning experiments, and construction of mathematical and computer models. (CS)

Laser ion source for isobaric heavy ion collider experiment.

PubMed

Kanesue, T; Kumaki, M; Ikeda, S; Okamura, M

2016-02-01

Heavy-ion collider experiment in isobaric system is under investigation at Relativistic Heavy Ion Collider. For this experiment, ion source is required to maximize the abundance of the intended isotope. The candidate of the experiment is (96)Ru + (96)Zr. Since the natural abundance of particular isotope is low and composition of isotope from ion source depends on the composites of the target, an isotope enriched material may be needed as a target. We studied the performance of the laser ion source required for the experiment for Zr ions.

Microgravity Combustion Science and Fluid Physics Experiments and Facilities for the ISS

NASA Technical Reports Server (NTRS)

Lauver, Richard W.; Kohl, Fred J.; Weiland, Karen J.; Zurawski, Robert L.; Hill, Myron E.; Corban, Robert R.

2001-01-01

At the NASA Glenn Research Center, the Microgravity Science Program supports both ground-based and flight experiment research in the disciplines of Combustion Science and Fluid Physics. Combustion Science research includes the areas of gas jet diffusion flames, laminar flames, burning of droplets and misting fuels, solids and materials flammability, fire and fire suppressants, turbulent combustion, reaction kinetics, materials synthesis, and other combustion systems. The Fluid Physics discipline includes the areas of complex fluids (colloids, gels, foams, magneto-rheological fluids, non-Newtonian fluids, suspensions, granular materials), dynamics and instabilities (bubble and drop dynamics, magneto/electrohydrodynamics, electrochemical transport, geophysical flows), interfacial phenomena (wetting, capillarity, contact line hydrodynamics), and multiphase flows and phase changes (boiling and condensation, heat transfer, flow instabilities). A specialized International Space Station (ISS) facility that provides sophisticated research capabilities for these disciplines is the Fluids and Combustion Facility (FCF). The FCF consists of the Combustion Integrated Rack (CIR), the Fluids Integrated Rack (FIR) and the Shared Accommodations Rack and is designed to accomplish a large number of science investigations over the life of the ISS. The modular, multiuser facility is designed to optimize the science return within the available resources of on-orbit power, uplink/downlink capacity, crew time, upmass/downmass, volume, etc. A suite of diagnostics capabilities, with emphasis on optical techniques, will be provided to complement the capabilities of the subsystem multiuser or principal investigator-specific experiment modules. The paper will discuss the systems concept, technical capabilities, functionality, and the initial science investigations in each discipline.

Microgravity Science in Space Flight Gloveboxes

NASA Technical Reports Server (NTRS)

Baugher, Charles; Bennett, Nancy; Cockrell, David; Jex, David; Musick, Barry; Poe, James; Roark, Walter

1998-01-01

Microgravity science studies the influences of gravity on phenomena in fluids, materials processes, combustion, and human cell growth in the low acceleration environment of space flight. During the last decade, the accomplishment of the flight research in the field has evolved into an effective cooperation between the flight crew in the Shuttle and the ground-based investigator using real-time communication via voice and video links. This team structure has led to interactive operations in which the crew performs the experimentation while guided, as necessary, by the science investigator who formulated the investigation and who will subsequently interpret and analyze the data. One of the primary challenges to implementing this interactive research has been the necessity of structuring a means of handling fluids, gases, and hazardous materials in a manned laboratory that exhibits the novelty of weightlessness. Developing clever means of designing experiments in closed vessels is part of the solution- but the space flight requirement for one and two failure-tolerant containment systems leads to serious complications in the physical handling of sample materials. In response to the conflict between the clear advantage of human operation and judgment, versus the necessity to isolate the experiment from the crewmember and the spacecraft environment, the Microgravity Research Program has initiated a series of Gloveboxes in the various manned experiment carriers. These units provide a sealed containment vessel whose interior is under a negative pressure with respect to the ambient environment but is accessible to a crewmember through the glove ports.

Selective visual working memory in fear of spiders: the role of automaticity and material-specificity.

PubMed

Reinecke, Andrea; Becker, Eni S; Rinck, Mike

2009-12-01

Following cognitive models of anxiety, biases occur if threat processing is automatic versus strategic. Therefore, most of these models predict attentional bias, but not explicit memory bias. We suggest dividing memory into the highly automatic working memory (WM) component versus long-term memory when investigating bias in anxiety. WM for threat has rarely been investigated although its main function is stimulus monitoring, particularly important in anxiety. We investigated WM for spiders in spider fearfuls (SFs) versus non-anxious controls (NACs). In Experiment 1 (23 SFs/24 NACs), we replicated an earlier WM study, reducing strategic processing options. This led to stronger group differences and, thus, clearer WM threat biases. There were no group differences in Experiment 2 (18 SFs/19 NACs), using snakes instead of spiders to test whether WM biases are material-specific. This article supports cognitive models of anxiety in that biases are more likely to occur when reducing strategic processing. However, it contradicts the assumption that explicit memory biases are not characteristic of anxiety.

Development and Flight of the NASA-Ames Research Center Payload on Spacelab-J

NASA Technical Reports Server (NTRS)

Schmidt, Gregory K.; Ball, Sally M.; Stolarik, Thomas M.; Eodice, Michael T.

1993-01-01

Spacelab-J was an international Spacelab mission with numerous innovative Japanese and American materials and life science experiments. Two of the Spacelab-J experiments were designed over a period of more than a decade by a team from NASA-Ames Research Center. The Frog Embryology Experiment investigated and is helping to resolve a century-long quandary on the effects of gravity on amphibian development. The Autogenic Feedback Training Experiment, flown on Spacelab-J as part of a multi-mission investigation, studied the effects of Autogenic Feedback Therapy on limiting the effects of Space Motion Sickness on astronauts. Both experiments employed the use of a wide variety of specially designed hardware to achieve the experiment objectives. This paper reviews the development of both experiments, from the initial announcement of opportunity in 1978, through selection on Spacelab-J and subsequent hardware and science procedures development, culminating in the highly successful Spacelab-J flight in September 1992.

Discrete meso-element simulation of chemical reactions in shear bands

NASA Astrophysics Data System (ADS)

Tamura, S.; Horie, Y.

1998-07-01

A meso-dynamic simulation technique is used to investigate the chemical reactions in high speed shearing of reactive porous mixtures. The reaction speed is assumed to be a function of temperature, pressure and mixing of materials. To gain a theoretical insight into the experiments reported by Nesterenko et al., a parametric study of material flow and local temperature was carried out using a Nb and Si mixture. In the model calculation, a heterogeneous shear region of 5 μm width, consisting of alternating layers of Nb and Si, was created first in a mixture and then sheared at the rate of 8.0×107s-1. Results show that the material flow is mostly homogeneous, but contains a local agglomeration and circulatory flow. This behavior accelerates mass mixing and causes a significant temperature increase. To evaluate the mixing of material, average minimum distance of materials separation was calculated. Voids effect were also investigated.

Deep Boreholes Seals Subjected to High P,T conditions - Proposed Experimental Studies

NASA Astrophysics Data System (ADS)

Caporuscio, F.

2015-12-01

Deep borehole experimental work will constrain the P,T conditions which "seal" material will experience in deep borehole crystalline rock repositories. The rocks of interest to this study include mafic (amphibolites) and silicic (granitic gneiss) end members. The experiments will systematically add components to capture discrete changes in both water and EBS component chemistries. Experiments in the system wall rock-clay-concrete-groundwater will evaluate interactions among components, including: mineral phase stability, metal corrosion rates and thermal limits. Based on engineered barrier studies, experimental investigations will move forward with three focusses. First, evaluation of interaction between "seal" materials and repository wall rock (crystalline) under fluid-saturated conditions over long-term (i.e., six-month) experiments; which reproduces the thermal pulse event of a repository. Second, perform experiments to determine the stability of zeolite minerals (analcime-wairakitess) under repository conditions. Both sets of experiments are critically important for understanding mineral paragenesis (zeolites and/or clay transformations) associated with "seals" in contact with wall rock at elevated temperatures. Third, mineral growth at the metal interface is a principal control on the survivability (i.e. corrosion) of waste canisters in a repository. The objective of this planned experimental work is to evaluate physio-chemical processes for 'seal' components and materials relevant to deep borehole disposal. These evaluations will encompass multi-laboratory efforts for the development of seals concepts and application of Thermal-Mechanical-Chemical (TMC) modeling work to assess barrier material interactions with subsurface fluids and other barrier materials, their stability at high temperatures, and the implications of these processes to the evaluation of thermal limits.

A data base describing low-gravity fluids and materials processing experiments

NASA Technical Reports Server (NTRS)

Winter, C. A.; Jones, J. C.

1992-01-01

A data base documenting information on approximately 600 fluids and materials processing experiments performed in a low-gravity environment has been prepared at NASA Marshall Space Flight Center (MSFC). The compilation was designed to document all such experimental efforts performed: (1) on U.S. manned space vehicles; (2) on payloads deployed from U.S. manned space vehicles; and (3) on all domestic and international sounding rocket programs (excluding those of the U.S.S.R. and China). Identification of major (reported) sources of significant anomalies during 100 of the experiments is reported and discussed. Further, a preliminary summary of the number of these 100 investigations which experienced an anomaly affecting a certain percentage of the experimental results/objectives is presented.

Surface design methodology - challenge the steel

NASA Astrophysics Data System (ADS)

Bergman, M.; Rosen, B.-G.; Eriksson, L.; Anderberg, C.

2014-03-01

The way a product or material is experienced by its user could be different depending on the scenario. It is also well known that different materials and surfaces are used for different purposes. When optimizing materials and surface roughness for a certain something with the intention to improve a product, it is important to obtain not only the physical requirements, but also the user experience and expectations. Laws and requirements of the materials and the surface function, but also the conservative way of thinking about materials and colours characterize the design of medical equipment. The purpose of this paper is to link the technical- and customer requirements of current materials and surface textures in medical environments. By focusing on parts of the theory of Kansei Engineering, improvements of the companys' products are possible. The idea is to find correlations between desired experience or "feeling" for a product, -customer requirements, functional requirements, and product geometrical properties -design parameters, to be implemented on new improved products. To be able to find new materials with the same (or better) technical requirements but a higher level of user stimulation, the current material (stainless steel) and its surface (brushed textures) was used as a reference. The usage of focus groups of experts at the manufacturer lead to a selection of twelve possible new materials for investigation in the project. In collaboration with the topical company for this project, three new materials that fulfil the requirements -easy to clean and anti-bacterial came to be in focus for further investigation in regard to a new design of a washer-disinfector for medical equipment using the Kansei based Clean ability approach CAA.

Plasma-Based Synthesis of Nanostructured Materials and their Characterization

NASA Astrophysics Data System (ADS)

Chaudhary, Rakesh P.

The aim of this thesis is to explore the novel cost-effective synthesis technique to develop nanostructured materials and investigate their structural and magnetic properties. Nanomaterials were synthesized by a plasma discharge between desired metal electrodes in the cavitation field of an organic solvent. Multifunctional core-shell magnetic nanoparticles of 3d transition elements (Fe, Ni) and bimetallic (FeNi) were synthesized by varying experimental conditions. The phase, crystallinity and the magnetic properties of the materials synthesized were found to be dependent on experimental reaction parameters such as different solvents, electrodes, the spacing between electrodes, applied voltage, experiment time and high-temperature annealing. Fe and Gd-based nanoparticles were developed for high-performance magnetic resonance imaging (MRI) contrast enhancement. Biocompatible hybrid composite of Fe core - C shell nanoparticles evaluated as negative MRI contrast agents display remarkably high transverse relaxivity (r2) of 70 mM-1S-1 at 7T. In addition to 3d transition magnetic materials, magnetism of multilayer graphene nanosheets with only s and p electrons was investigated to understand and explain the intrinsic origin of ferromagnetism in carbon-based material. Apart from magnetic materials, noble metal Pd nanoparticles were developed using one-step process for hydrogen storage. The role of hydrogen on the dilation of Pd lattice was investigated using the experiment and density functional theory (DFT) studies. This method demonstrates that plasma discharge method using appropriate electrodes and solvents can be used to synthesize desired nanoparticles. This potential emphasizes the importance of adopting this methodology, which offers advantages that include a rapid reaction rate and ability to form very small nanoparticles with narrow size distribution.

A theoretical and numerical study of the flow of granular materials down an inclined plane. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rajagopal, K.R.

The mechanics of the flowing granular materials such as coal, agricultural products, at deal of attention as it has fertilizers, dry chemicals, metal ores, etc. have received a great deal of attention as it has relevance to several important technological problems. Despite wide interest and more than five decades of experimental and theoretical investigations, most aspects of the behavior of flowing granular materials are still not well understood. So Experiments have to be devised which quantify and describe the non-linear behavior of the modular materials, and theories developed which can explain the experimentally observed facts. As many models have beenmore » suggested for describing the behavior of granular materials, from both continuum and kinetic theory viewpoints, we proposed to investigate the validity and usefulness of representative models from both the continuum and kinetic theory points of view, by determining the prediction of such a theory, in a representative flow, with respect to existence, non-existence, multiplicity and stability of solutions. The continuum model to be investigated is an outgrowth of a model due to Goodman and Cowin (1971, 1972) and the kinetic theory models being those due to Jenkins and Richman (1985) and Boyle and Massoudi (1989). In this report we present detailed results regarding the same. Interestingly, we find that the predictions of all the theories, in certain parameter space associated with these models, are qualitatively similar. This ofcourse depends on the values assumed for various material parameters in the models, which as yet are unknown, as reliable experiments have not been carried out as yet for their determination.« less

Local mechanical properties of LFT injection molded parts: Numerical simulations versus experiments

NASA Astrophysics Data System (ADS)

Desplentere, F.; Soete, K.; Bonte, H.; Debrabandere, E.

2014-05-01

In predictive engineering for polymer processes, the proper prediction of material microstructure from known processing conditions and constituent material properties is a critical step forward properly predicting bulk properties in the finished composite. Operating within the context of long-fiber thermoplastics (LFT, length < 15mm) this investigation concentrates on the prediction of the local mechanical properties of an injection molded part. To realize this, the Autodesk Simulation Moldflow Insight 2014 software has been used. In this software, a fiber breakage algorithm for the polymer flow inside the mold is available. Using well known micro mechanic formulas allow to combine the local fiber length with the local orientation into local mechanical properties. Different experiments were performed using a commercially available glass fiber filled compound to compare the measured data with the numerical simulation results. In this investigation, tensile tests and 3 point bending tests are considered. To characterize the fiber length distribution of the polymer melt entering the mold (necessary for the numerical simulations), air shots were performed. For those air shots, similar homogenization conditions were used as during the injection molding tests. The fiber length distribution is characterized using automated optical method on samples for which the matrix material is burned away. Using the appropriate settings for the different experiments, good predictions of the local mechanical properties are obtained.

Bubble and Drop Nonlinear Dynamics experiment

NASA Technical Reports Server (NTRS)

2003-01-01

The Bubble and Drop Nonlinear Dynamics (BDND) experiment was designed to improve understanding of how the shape and behavior of bubbles respond to ultrasound pressure. By understanding this behavior, it may be possible to counteract complications bubbles cause during materials processing on the ground. This 12-second sequence came from video downlinked from STS-94, July 5 1997, MET:3/19:15 (approximate). The BDND guest investigator was Gary Leal of the University of California, Santa Barbara. The experiment was part of the space research investigations conducted during the Microgravity Science Laboratory-1R mission (STS-94, July 1-17 1997). Advanced fluid dynamics experiments will be a part of investigations plarned for the International Space Station. (189KB JPEG, 1293 x 1460 pixels; downlinked video, higher quality not available) The MPG from which this composite was made is available at http://mix.msfc.nasa.gov/ABSTRACTS/MSFC-0300163.html.

Mathematical Modeling of Ultraporous Nonmetallic Reticulated Materials

NASA Astrophysics Data System (ADS)

Alifanov, O. M.; Cherepanov, V. V.; Morzhukhina, A. V.

2015-01-01

We have developed an imitation statistical mathematical model reflecting the structure and the thermal, electrophysical, and optical properties of nonmetallic ultraporous reticulated materials. This model, in combination with a nonstationary thermal experiment and methods of the theory of inverse heat transfer problems, permits determining the little-studied characteristics of the above materials such as the radiative and conductive heat conductivities, the spectral scattering and absorption coefficients, the scattering indicatrix, and the dielectric constants, which are of great practical interest but are difficult to investigate.

Proceedings of the LDEF Materials Data Analysis Workshop

NASA Technical Reports Server (NTRS)

Stein, Bland A. (Compiler); Young, Philip R. (Compiler)

1990-01-01

The 5-year, 10-month flight of the Long Duration Exposure Facility (LDEF) greatly enhanced the potential value of most LDEF materials, compared to the original 1-year flight plan. NASA recognized this potential by forming the LDEF Space Environmental Effects on Materials Special Investigation Group in early 1989 to address the expanded opportunities available in the LDEF structure and on experimental trays, so that the value of all LDEF materials to current and future space missions would be assessed and documented. The LDEF Materials Data Analysis Workshop served as one step toward the realization of that responsibility and ran concurrently with activities surrounding the successful return of the spacecraft to the NASA Kennedy Space Center. A compilation of visual aids utilized by speakers at the workshop is presented. Session 1 summarized current information on analysis responsibilities and plans and was aimed at updating the workshop attendees: the LDEF Advisory Committee, Principle Investigators, Special Investigation Group Members, and others involved in LDEF analyses or management. Sessions 2 and 3 addressed materials data analysis methodology, specimen preparation, shipment and archival, and initial plans for the LDEF Materials Data Base. A complementary objective of the workshop was to stimulate interest and awareness of opportunities to vastly expand the overall data base by considering the entire spacecraft as a materials experiment.

Mechanics of Granular Materials (MGM) Test Cell

NASA Technical Reports Server (NTRS)

1998-01-01

A test cell for Mechanics of Granular Materials (MGM) experiment is shown approximately 20 and 60 minutes after the start of an experiment on STS-89. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditons that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: NASA/Marshall Space Flight Center (MSFC)

Mechanical testing of bones: the positive synergy of finite-element models and in vitro experiments.

PubMed

Cristofolini, Luca; Schileo, Enrico; Juszczyk, Mateusz; Taddei, Fulvia; Martelli, Saulo; Viceconti, Marco

2010-06-13

Bone biomechanics have been extensively investigated in the past both with in vitro experiments and numerical models. In most cases either approach is chosen, without exploiting synergies. Both experiments and numerical models suffer from limitations relative to their accuracy and their respective fields of application. In vitro experiments can improve numerical models by: (i) preliminarily identifying the most relevant failure scenarios; (ii) improving the model identification with experimentally measured material properties; (iii) improving the model identification with accurately measured actual boundary conditions; and (iv) providing quantitative validation based on mechanical properties (strain, displacements) directly measured from physical specimens being tested in parallel with the modelling activity. Likewise, numerical models can improve in vitro experiments by: (i) identifying the most relevant loading configurations among a number of motor tasks that cannot be replicated in vitro; (ii) identifying acceptable simplifications for the in vitro simulation; (iii) optimizing the use of transducers to minimize errors and provide measurements at the most relevant locations; and (iv) exploring a variety of different conditions (material properties, interface, etc.) that would require enormous experimental effort. By reporting an example of successful investigation of the femur, we show how a combination of numerical modelling and controlled experiments within the same research team can be designed to create a virtuous circle where models are used to improve experiments, experiments are used to improve models and their combination synergistically provides more detailed and more reliable results than can be achieved with either approach singularly.

Suitable utilization of woody plants for hibitation on Mars

NASA Astrophysics Data System (ADS)

Tomita-Yokotani, Kaori; Baba, Keiichi; Suzuki, Toshisada; Kimura, Shunta; Sato, Seigo; Katoh, Hiroshi; Abe, Yusuke; Katayama, Takeshi

2016-07-01

We have been investigating the usefulness of woody plants for habitation on Mars. During our research, we have found that woody plants have several properties which can be utilized for therapy and materials for enrage and construction even on Mars. Japanese people traditionally believe that "Bonsai" have therapeudic properties. Trees can become carbon fuel which can be used as energy on Mars. Tree materials could be used as a tool in closed bio-ecosystems such as for the purification and/or separation of solutions in an environment in space. Here, we will show some results of their abilities, the water leakage and vacuum seal test, separation of solutions using carbon materials made from trees. At the initiation of this research, we named the trees used as material for the experiment related to space environments "CosmoBon", small bonsai tree. To establish our research, as the first step, we will try to do the experiment using "CosmoBon".

A microfluidic investigation of gas exsolution in glass and shale fracture networks

NASA Astrophysics Data System (ADS)

Porter, M. L.; Jimenez-Martinez, J.; Harrison, A.; Currier, R.; Viswanathan, H. S.

2016-12-01

Microfluidic investigations of pore-scale fluid flow and transport phenomena has steadily increased in recent years. In these investigations fluid flow is restricted to two-dimensions allowing for real-time visualization and quantification of complex flow and reactive transport behavior, which is difficult to obtain in other experimental systems. In this work, we describe a unique high pressure (up to 10.3 MPa) and temperature (up to 80 °C) microfluidics experimental system that allows us to investigate fluid flow and transport in geo-material (e.g., shale, Portland cement, etc.) micromodels. The use of geo-material micromodels allows us to better represent fluid-rock interactions including wettability, chemical reactivity, and nano-scale porosity at conditions representative of natural subsurface environments. Here, we present experimental results in fracture systems with applications to hydrocarbon mobility in fractured rocks. Complex fracture network patterns are derived from 3D x-ray tomography images of actual fractures created in shale rock cores. We use both shale and glass micromodels, allowing for a detailed comparison between flow phenomena in the different materials. We discuss results from two-phase gas (CO2 and N2) injection experiments designed to enhance oil recovery. In these experiments gas was injected into micromodels saturated with oil and allowed to soak for approximately 12 hours at elevated pressures. The pressure in the system was then decreased to atmospheric, causing the gas to expand and/or dissolve out of solution, subsequently mobilizing the oil. In addition to the experimental results, we present a relatively simple model designed to quantify the amount of oil mobilized as a function of decreasing system pressure. We will show comparisons between the experiments and model, and discuss the potential use of the model in field-scale reservoir simulations.

Efficiency Improvement of Some Agricultural Residue Modified Materials for Textile Dyes Absorption

NASA Astrophysics Data System (ADS)

Boonsong, P.; Paksamut, J.

2018-03-01

In this work, the adsorption efficiency was investigated of some agricultural residue modified materials as natural bio-adsorbents which were rice straw (Oryza sativa L.) and pineapple leaves (Ananas comosus (L.) Merr.) for the removal of textile dyes. Reactive dyes were used in this research. The improvement procedure of agricultural residue materials properties were alkali-acid modification with sodium hydroxide solution and hydrochloric acid solution. Adsorption performance has been investigated using batch experiments. Investigated adsorption factors consisted of adsorbent dose, contact time, adsorbent materials and pH of solution. The results were found that rice straw had higher adsorption capacity than pineapple leaves. The increasing of adsorption capacity depends on adsorbent dose and contact time. Moreover, the optimum pH for dye adsorption was acidic range because lowering pH increased the positively charges on the adsorbent surface which could be attacked by negatively charge of acid dyes. The agricultural residue modified materials had significant dye removal efficiency which these adsorbents could be used for the treatment of textile effluent in industries.

Materials Science Laboratory - Columnar-to-Equiaxed Transition in Solidification Processing and Microstructure Formation in Casting of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions

NASA Technical Reports Server (NTRS)

Gandin, Charles-Andre; Ratke, Lorenz

2008-01-01

The Materials Science Laboratory - Columnar-to-Equiaxed Transition in Solidification Processing and Microstructure Formation in Casting of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions (MSL-CETSOL and MICAST) are two investigations which supports research into metallurgical solidification, semiconductor crystal growth (Bridgman and zone melting), and measurement of thermo-physical properties of materials. This is a cooperative investigation with the European Space Agency (ESA) and National Aeronautics and Space Administration (NASA) for accommodation and operation aboard the International Space Station (ISS). Research Summary: Materials Science Laboratory - Columnar-to-Equiaxed Transition in Solidification Processing (CETSOL) and Microstructure Formation in Casting of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions (MICAST) are two complementary investigations which will examine different growth patterns and evolution of microstructures during crystallization of metallic alloys in microgravity. The aim of these experiments is to deepen the quantitative understanding of the physical principles that govern solidification processes in cast alloys by directional solidification.

Further investigations of experiment A0034 atomic oxygen stimulated outgassing

NASA Technical Reports Server (NTRS)

Linton, Roger C.; Finckenor, Miria M.; Kamenetzky, Rachel R.

1995-01-01

Thermal control coatings within the recessed compartments of LDEF Experiment A0034 experienced the maximum leading edge fluence of atomic oxygen with considerably less solar UV radiation exposure than top-surface mounted materials of other LDEF experiments on either the leading or the trailing edge. This combination of exposure within A0034 resulted in generally lower levels of darkening attributable to solar UV radiation than for similar materials on other LDEF experiments exposed to greater cumulative solar UV radiation levels. Changes in solar absorptance and infrared thermal emittance of the exposed coatings are thus unique to this exposure. Analytical results for other applications have been found for environmentally induced changes in fluorescence, surface morphology, light scattering, and the effects of coating outgassing products on adjacent mirrors and windows of the A0034 experiment. Some atmospheric bleaching of the thermal control coatings, in addition to that presumably experience during reentry and recovery operations, has been found since initial post-flight observations and measurements.

Children's Lived Experience and Their Sense of Coherence: Bodily Play in a Norwegian After-School Programme

ERIC Educational Resources Information Center

Londal, Knut

2010-01-01

This article is based on materials gathered from qualitative research interviews among eight-year-old and nine-year-old children participating in an after-school programme (ASP) in Oslo, and investigates how bodily play affects their sense of coherence (SOC). In line with Maurice Merleau-Ponty, children's lived experiences are regarded as layered…

Electrochemical research in chemical hydrogen storage materials: Sodium borohydride and organotin hydrides

NASA Astrophysics Data System (ADS)

McLafferty, Jason

Chemical storage of hydrogen involves release of hydrogen in a controlled manner from materials in which the hydrogen is covalently bound. Sodium borohydride and aminoborane are two materials given consideration as chemical hydrogen storage materials by the US Department of Energy. A very significant barrier to adoption of these materials as hydrogen carriers is their regeneration from "spent fuel," i.e., the material remaining after discharge of hydrogen. In this thesis, some research directed at regeneration of sodium borohydride and aminoborane is described. For sodium borohydride, electrochemical reduction of boric acid and sodium metaborate (representing spent fuel) in alkaline, aqueous solution has been investigated. Similarly to literature reports (primarily patents), a variety of cathode materials were tried in these experiments. Additionally, approaches directed at overcoming electrostatic repulsion of borate anion from the cathode, not described in the previous literature for electrochemical reduction of spent fuels, have been attempted. A quantitative analytical method for measuring the concentration of sodium borohydride in alkaline aqueous solution has been developed as part of this work and is described herein. Finally, findings from stability tests for sodium borohydride in aqueous solutions of several different compositions are reported. For aminoborane, other research institutes have developed regeneration schemes involving tributyltin hydride. In this thesis, electrochemical reduction experiments attempting to regenerate tributyltin hydride from tributyltin chloride (a representative by-product of the regeneration scheme) are described. These experiments were performed in the non-aqueous solvents acetonitrile and 1,2-dimethoxyethane. A non-aqueous reference electrode for electrolysis experiments in acetonitrile was developed and is described.

Delayed Release from Proactive Interference with Meaningful Material: How Much Do We Remember After Reading Brief Prose Passages?

ERIC Educational Resources Information Center

Blumenthal, Gary B.; Robbins, Donald

1977-01-01

Three experiments were conducted, investigating the buildup of and the release from proactive interference, in which the stimulus materials were brief prose passages about specific topics. Each passage was followed by a multiple-choice test, and then a final test on all the passages read was given. Implications of the data for standardized tests…

A Study of the Effects of a Structured Curriculum in Piagetian Type Operations on the Cognitive Coping of Elementary School Children.

ERIC Educational Resources Information Center

Breidenbaugh, Barry Ellis

The purpose of this study was to investigate the effects of the Material Objects Unit of the Science Curriculum Improvement Study (SCIS) on the cognitive operations and academic achievement of elementary school children. The Material Objects Unit was designed to give experiences and explorations in the mental operations of classification,…

Study of PMMA materials for a digital optical module

NASA Astrophysics Data System (ADS)

Spina, Roberto; Tricarico, Luigi; Berardi, Vincenzo; De Rosa, Gianfranca; Ruggeri, Alan C.; Mastrorilli, Piero

2018-05-01

This work illustrates the material characterization to realize of a prototypal polymeric cover of a Digital Optical Module for the Hyper-Kamiokande neutrino experiment. The cover was made of a high transmittance poly-methyl methacrylate (PMMA), used as a glass substitute. The main objective of the present research is to investigate the structural and optical properties of PMMA, evaluating the respect of the project specification.

Spacelab

NASA Image and Video Library

1992-01-01

The IML-1 mission was the first in a series of Shuttle flights dedicated to fundamental materials and life sciences research with the international partners. The participating space agencies included: NASA, the 14-nation European Space Agency (ESA), the Canadian Space Agency (CSA), The French National Center of Space Studies (CNES), the German Space Agency and the German Aerospace Research Establishment (DAR/DLR), and the National Space Development Agency of Japan (NASDA). Dedicated to the study of life and materials sciences in microgravity, the IML missions explored how life forms adapt to weightlessness and investigated how materials behave when processed in space. Both life and materials sciences benefited from the extended periods of microgravity available inside the Spacelab science module in the cargo bay of the Space Shuttle Orbiter. This photograph shows Astronaut Norman Thagard performing the fluid experiment at the Fluid Experiment System (FES) facility inside the laboratory module. The FES facility had sophisticated optical systems for imaging fluid flows during materials processing, such as experiments to grow crystals from solution and solidify metal-modeling salts. A special laser diagnostic technique recorded the experiments, holograms were made for post-flight analysis, and video was used to view the samples in space and on the ground. Managed by the Marshall Space Flight Center (MSFC), the IML-1 mission was launched on January 22, 1992 aboard the Shuttle Orbiter Discovery (STS-42).

The Distracting Effects of a Ringing Cell Phone: An Investigation of the Laboratory and the Classroom Setting

PubMed Central

Shelton, Jill T.; Elliott, Emily M.; Lynn, Sharon D.; Exner, Amanda L.

2010-01-01

The detrimental effects of a ringing phone on cognitive performance were investigated in four experiments. In Experiments 1 and 2, the effects of different types of sounds (a standard cell phone ring, irrelevant tones and an instrumental song commonly encountered by participants) on performance were examined. In Experiment 1, slower responses were observed in all auditory groups relative to a silence condition, but participants in the ring and song conditions recovered more slowly. In Experiment 2, participants who were warned about the potential for distraction recovered more quickly, suggesting a benefit of this prior knowledge. This investigation continued in a college classroom setting (Experiments 3a and 3b); students were exposed to a ringing cell phone during the lecture. Performance on a surprise quiz revealed low accuracy rates on material presented while the phone was ringing. These findings offer insight into top-down cognitive processes that moderate involuntary orienting responses associated with a common stimulus encountered in the environment. PMID:21234286

Convection effects on Skylab experiments M551, M552, and M553, phase C report. [metal melting, exothermic brazing, and sphere forming under weightless conditions

NASA Technical Reports Server (NTRS)

Bourgeois, S. V.

1973-01-01

This report described an analysis of Skylab Experiments M551 (Metals Melting), M552 (Exothermic Brazing), and M553 (Sphere Forming). The primary objective is the study of convection in the molten metals and their attendant solidification theory. Particular attention is given to clarifying the effects of reduced gravity on molten metal flow and solidification. Based on an analysis of physical forces and solidification theory expected for ground-based and Skylab processing, low-g variations were predicted for each experiment. A comparison was then made with the Skylab results available to date. Both metallurgical analyses of other investigators and movies of ground-based and Skylab samples were utilized. Several low-g variations in Skylab processed materials were successfully predicted based on expected variations in physical forces and fluid convection. The same analysis also successfully predicted several features in the Skylab-processed materials which were identical to terrestrially-processed materials. These results are summarized in the conclusion section for each experiment.

Characterizing and modeling the free recovery and constrained recovery behavior of a polyurethane shape memory polymer

NASA Astrophysics Data System (ADS)

Volk, Brent L.; Lagoudas, Dimitris C.; Maitland, Duncan J.

2011-09-01

In this work, tensile tests and one-dimensional constitutive modeling were performed on a high recovery force polyurethane shape memory polymer that is being considered for biomedical applications. The tensile tests investigated the free recovery (zero load) response as well as the constrained displacement recovery (stress recovery) response at extension values up to 25%, and two consecutive cycles were performed during each test. The material was observed to recover 100% of the applied deformation when heated at zero load in the second thermomechanical cycle, and a stress recovery of 1.5-4.2 MPa was observed for the constrained displacement recovery experiments. After the experiments were performed, the Chen and Lagoudas model was used to simulate and predict the experimental results. The material properties used in the constitutive model—namely the coefficients of thermal expansion, shear moduli, and frozen volume fraction—were calibrated from a single 10% extension free recovery experiment. The model was then used to predict the material response for the remaining free recovery and constrained displacement recovery experiments. The model predictions match well with the experimental data.

Dynamics of bubble collapse under vessel confinement in 2D hydrodynamic experiments

NASA Astrophysics Data System (ADS)

Shpuntova, Galina; Austin, Joanna

2013-11-01

One trauma mechanism in biomedical treatment techniques based on the application of cumulative pressure pulses generated either externally (as in shock-wave lithotripsy) or internally (by laser-induced plasma) is the collapse of voids. However, prediction of void-collapse driven tissue damage is a challenging problem, involving complex and dynamic thermomechanical processes in a heterogeneous material. We carry out a series of model experiments to investigate the hydrodynamic processes of voids collapsing under dynamic loading in configurations designed to model cavitation with vessel confinement. The baseline case of void collapse near a single interface is also examined. Thin sheets of tissue-surrogate polymer materials with varying acoustic impedance are used to create one or two parallel material interfaces near the void. Shadowgraph photography and two-color, single-frame particle image velocimetry quantify bubble collapse dynamics including jetting, interface dynamics and penetration, and the response of the surrounding material. Research supported by NSF Award #0954769, ``CAREER: Dynamics and damage of void collapse in biological materials under stress wave loading.''

Characteristics of Bone Tissue and Composite Materials on the Basis of Natural Hydroxyapatite and Endodontic Cement for Replacement of the Tissue

NASA Astrophysics Data System (ADS)

Filipenkov, V. V.; Rupeks, L. E.; Vitins, V. M.; Knets, I. V.; Kasyanov, V. A.

2017-07-01

New biocomposites and the cattle bone tissue were investigated. The composites were made from an endodontic cement (EC) and natural hydroxyapatite (NHAp.) The results of experiments performed by the method of infrared spectroscopy showed that protein was removed from the heat-treated specimens of bone tissue practically completely. The structure of bone tissue before and after deproteinization and the structure of the composite materials based on NHAp and EC (with different percentage) were investigated by the method of optical microscopy. The characteristics of mechanical properties (the initial elastic modulus, breaking tensile and compressive stresses, and breaking strain) and the density and porosity of these materials were determined. The new composite materials were implanted in the live tissue of rat. Biocompatibility between the live tissue and the new biocomposites was estimated.

Extraterrestrial materials processing and construction

NASA Technical Reports Server (NTRS)

Criswell, D. R.

1978-01-01

Applications of available terrestrial skills to the gathering of lunar materials and the processing of raw lunar materials into industrial feed stock were investigated. The literature on lunar soils and rocks was reviewed and the chemical processes by which major oxides and chemical elements can be extracted were identified. The gathering of lunar soil by means of excavation equipment was studied in terms of terrestrial experience with strip mining operations on earth. The application of electrostatic benefication techniques was examined for use on the moon to minimize the quantity of materials requiring surface transport and to optimize the stream of raw materials to be transported off the moon for subsequent industrial use.

Mechanics of Granular Materials (MGM) Investigators

NASA Technical Reports Server (NTRS)

2000-01-01

Key persornel in the Mechanics of Granular Materials (MGM) experiment at the University of Colorado at Boulder include Tawnya Ferbiak (software engineer), Susan Batiste (research assistant), and Christina Winkler (graduate research assistant). Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. MGM experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditions that cannot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. (Credit: University of Colorado at Boulder).

Anodized titanium and stainless steel in contact with CFRP: an electrochemical approach considering galvanic corrosion.

PubMed

Mueller, Yves; Tognini, Roger; Mayer, Joerg; Virtanen, Sannakaisa

2007-09-15

The combination of different materials in an implant gives the opportunity to better fulfill the requirements that are needed to improve the healing process. However, using different materials increases the risk of galvanic coupling corrosion. In this study, coupling effects of gold-anodized titanium, stainless steel for biomedical applications, carbon fiber reinforced polyetheretherketone (CFRP), and CFRP containing tantalum fibers are investigated electrochemically and by long-term immersion experiments in simulated body fluid (SBF). Potentiodynamic polarization experiments (i/E curves) and electrochemical impedance spectroscopy (EIS) of the separated materials showed a passive behavior of the metallic samples. Anodized titanium showed no corrosion attacks, whereas stainless steel is highly susceptibility for localized corrosion. On the other side, an active dissolution behavior of both of the CFRPs in the given environment could be determined, leading to delaminating of the carbon fibers from the matrix. Long-term immersion experiments were carried out using a set-up especially developed to simulate coupling conditions of a point contact fixator system (PC-Fix) in a biological environment. Electrochemical data were acquired in situ during the whole immersion time. The results of the immersion experiments correlate with the findings of the electrochemical investigation. Localized corrosion attacks were found on stainless steel, whereas anodized titanium showed no corrosion attacks. No significant differences between the two CFRP types could be found. Galvanic coupling corrosion in combination with crevice conditions and possible corrosion mechanisms are discussed. Copyright 2007 Wiley Periodicals, Inc.

Plasma chamber testing of advanced photovoltaic solar array coupons

NASA Technical Reports Server (NTRS)

Hillard, G. Barry

1994-01-01

The solar array module plasma interactions experiment is a space shuttle experiment designed to investigate and quantify the high voltage plasma interactions. One of the objectives of the experiment is to test the performance of the Advanced Photovoltaic Solar Array (APSA). The material properties of array blanket are also studied as electric insulators for APSA arrays in high voltage conditions. Three twelve cell prototype coupons of silicon cells were constructed and tested in a space simulation chamber.

Effect of porous material heating on the drag force of a cylinder with gas-permeable porous inserts in a supersonic flow

NASA Astrophysics Data System (ADS)

Mironov, S. G.; Poplavskaya, T. V.; Kirilovskiy, S. V.

2017-10-01

The paper presents the results of an experimental investigation of supersonic flow around a solid cylinder with a gas-permeable porous insert on its front end and of supersonic flow around a hollow cylinder with internal porous inserts in the presence of heating of the porous material. The experiments were performed in a supersonic wind tunnel with Mach number 4.85 and 7 with porous inserts of cellular-porous nickel. The results of measurements on the filtration stand of the air filtration rate through the cellular-porous nickel when it is heated are also shown. For a number of experiments, numerical modeling based on the skeletal model of a cellular-porous material was carried out.

Low-Earth orbit effects on organic composite materials flown on LDEF

NASA Technical Reports Server (NTRS)

George, Pete E.; Dursch, Harry W.

1993-01-01

Over 35 different types of organic matrix composites were flown as part of 11 different experiments onboard the NASA Long Duration Exposure Facility (LDEF) satellite. This materials and systems experiment satellite flew in low-earth orbit (LEO) for 69 months. For that period, the experiments were subjected to the LEO environment including atomic oxygen (AO), ultraviolet (UV) radiation, thermal cycling, microvacuum, meteoroid and space debris (M&D), and particle radiation. Since retrieval of the satellite in January of 1990, the principal experiment investigators have been deintegrating, examining, and testing the materials specimens flown. The most detrimental environmental effect on all organic matrix composites was material loss due to AO erosion. AO erosion of uncoated organic matrix composites (OMC) facing the satellite ram direction was responsible for significant mechanical property degradations. Also, thermal cycling-induced microcracking was observed in some nonunidirectional reinforced OMC's. Thermal cycling and outgassing caused significant but predictable dimensional changes as measured in situ on one experiment. Some metal and metal oxide-based coatings were found to be very effective at preventing AO erosion of OMC's. However, M&D impacts and coating fractures which compromised these coatings allowed AO erosion of the underlying OMC substrates. The findings for organic matrix composites flown on the LDEF are summarized and the LEO environmental factors, their effects, and the influence on space hardware design factors for LEO applications are identified.

F4TCNQ-Induced Exciton Quenching Studied by Using in-situ Photoluminescence Measurements

NASA Astrophysics Data System (ADS)

Zhu, Jian; Lu, Min; Wu, Bo; Hou, Xiao-Yuan

2012-09-01

The role of F4TCNQ as an exciton quenching material in thin organic light-emitting films is investigated by means of in situ photoluminescence measurements. C60 was used as another quenching material in the experiment for comparison, with Alq3 as a common organic light-emitting material. The effect of the growth sequence of the materials on quenching was also examined. It is found that the radius of Förster energy transfer between F4TCNQ and Alq3 is close to 0 nm and Dexter energy transfer dominates in the quenching process.

Feasibility of Pb phytoextraction using nano-materials assisted ryegrass: Results of a one-year field-scale experiment.

PubMed

Liang, Shu-Xuan; Jin, Yu; Liu, Wei; Li, Xiliang; Shen, Shi-Gang; Ding, Ling

2017-04-01

The effect of the combined application of nano-hydroxyapatite (NHAP) or nano-carbon black (NCB) on the phytoextraction of Pb by ryegrass was investigated as an enhanced remediation technique for soils by field-scale experiment. After the addition of 0.2% NHAP or NCB to the soil, temporal variation of the uptake of Pb in aboveground parts and roots were observed. Ryegrass shoot concentrations of Pb were lower with nano-materials application than without nano-materials for the first month. However, the shoot concentrations of Pb were significantly increased with nano-materials application, in particular NHAP groups. The ryegrass root concentrations of Pb were lower with nano-materials application for the first month. These results indicated that nano-materials had significant effects on stabilization of lead, especially at the beginning of the experiment. Along with the experimental proceeding, phytotoxicity was alleviated after the incorporation of nano-materials. The ryegrass biomass was significantly higher with nano-materials application. Consequently, the Pb phytoextraction potential of ryegrass significantly increased with nano-materials application compared to the gounps without nano-materials application. The total removal rates of soil Pb were higher after combined application of NHAP than NCB. NHAP is more suitable than NCB for in-situ remediation of Pb-contaminated soils. The ryegrass translocation factor exhibited a marked increase with time. It was thought that the major role of NHP and NBA might be to alleviate the Pb phytotoxicity and increase biomass of plants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Investigating the use of mastery-style online homework exercises in introductory algebra-based mechanics in a controlled clinical study

NASA Astrophysics Data System (ADS)

Evans, William R.; Selen, Mats A.

2017-12-01

Homework in introductory physics represents an important part of a student's learning experience; therefore, choosing the manner in which homework is presented merits investigation. We performed three rounds of clinical trials comparing the effects of mastery-style homework vs traditional-style homework with students in both algebra-based and calculus-based introductory mechanics. Results indicate a benefit from mastery-style over traditional-style homework, principally for weaker students who are less familiar with the material being covered and on questions that are nearer transfer to the study materials.

TES (Thermal Energy Storage) Video News Release

NASA Technical Reports Server (NTRS)

1994-01-01

TES is an in-space technology experiment that flew on STS-62. Its intent is to investigate the behavior of two different thermal energy storage materials as they undergo repeated melting and freezing in the microgravity environment.

The investigation of degradation reaction of various saccharides in high temperature and high pressure water

NASA Astrophysics Data System (ADS)

Saito, T.; Noguchi, S.; Matsumoto, T.; Sasaki, M.; Goto, M.

2008-07-01

Recently, conversions of polysaccharides included in biomass resources have been studied in order to recover valuable chemicals. Degradation of polysaccharides has been attracted by many researchers, whereas by-products from secondary reactions of the materials have not been studied very well. For the purpose of understanding reaction behavior of various monosaccharides in high-temperature and high-pressure water regions, we investigated reaction pathway and kinetics through reaction experiments of degradation of saccharides in subcritical water. The experiment was conducted by using continuous flow-type micro-reactors. Glucose was used as the starting material. From the experimental results, the conversion of glucose increased with increasing the residence time. The yields of fructose and 1, 6-anhydro-β-D-glucose decreased with increasing the residence time. The yields of organic acids and some aldehydes increased with increasing the residence time.

Material Science

NASA Image and Video Library

2004-07-03

Astronaut Mike Fincke places droplets of honey onto the strings for the Fluid Merging Viscosity Measurement (FMVM) investigation onboard the International Space Station (ISS). The FMVM experiment measures the time it takes for two individual highly viscous fluid droplets to coalesce or merge into one droplet. Different fluids and droplet size combinations were tested in the series of experiments. By using the microgravity environment, researchers can measure the viscosity or "thickness" of fluids without the influence of containers and gravity using this new technique. Understanding viscosity could help scientists understand industrially important materials such as paints, emulsions, polymer melts and even foams used to produce pharmaceutical, food, and cosmetic products.

Material Science

NASA Image and Video Library

2004-07-12

Astronaut Mike Fincke places droplets of honey onto the strings for the Fluid Merging Viscosity Measurement (FMVM) investigation onboard the International Space Station (ISS). The FMVM experiment measures the time it takes for two individual highly viscous fluid droplets to coalesce or merge into one droplet. Different fluids and droplet size combinations were tested in the series of experiments. By using the microgravity environment, researchers can measure the viscosity or "thickness" of fluids without the influence of containers and gravity using this new technique. Understanding viscosity could help scientists understand industrially important materials such as paints, emulsions, polymer melts and even foams used to produce pharmaceutical, food, and cosmetic products.

Simulation of Foam Impact Effects on Components of the Space Shuttle Thermal Protection System. Chapter 7

NASA Technical Reports Server (NTRS)

Fahrenthold, Eric P.; Park, Young-Keun

2004-01-01

A series of three dimensional simulations has been performed to investigate analytically the effect of insulating foam impacts on ceramic tile and reinforced carbon-carbon components of the Space Shuttle thermal protection system. The simulations employed a hybrid particle-finite element method and a parallel code developed for use in spacecraft design applications. The conclusions suggested by the numerical study are in general consistent with experiment. The results emphasize the need for additional material testing work on the dynamic mechanical response of thermal protection system materials, and additional impact experiments for use in validating computational models of impact effects.

Calculational investigation of impact cratering dynamics - Material motions during the crater growth period

NASA Technical Reports Server (NTRS)

Austin, M. G.; Thomsen, J. M.; Ruhl, S. F.; Orphal, D. L.; Schultz, P. H.

1980-01-01

The considered investigation was conducted in connection with studies which are to provide a better understanding of the detailed dynamics of impact cratering processes. Such an understanding is vital for a comprehension of planetary surfaces. The investigation is the continuation of a study of impact dynamics in a uniform, nongeologic material at impact velocities achievable in laboratory-scale experiments conducted by Thomsen et al. (1979). A calculation of a 6 km/sec impact of a 0.3 g spherical 2024 aluminum projectile into low strength (50 kPa) homogeneous plasticene clay has been continued from 18 microseconds to past 600 microseconds. The cratering flow field, defined as the material flow field in the target beyond the transient cavity but well behind the outgoing shock wave, has been analyzed in detail to see how applicable the Maxwell Z-Model, developed from analysis of near-surface explosion cratering calculations, is to impact cratering

A study on the strength of an armour-grade aluminum under high strain-rate loading

NASA Astrophysics Data System (ADS)

Appleby-Thomas, G. J.; Hazell, P. J.

2010-06-01

The aluminum alloy 5083 in tempers such as H32 and H131 is an established light-weight armour material. While its dynamic response under high strain-rates has been investigated elsewhere, little account of the effect of material orientation has been made. In addition, little information on its strength under such loadings is available in the literature. Here, both the longitudinal and lateral components of stress have been measured using embedded manganin stress gauges during plate-impact experiments on samples with the rolling direction aligned both orthogonal and parallel to the impact axis. The Hugoniot elastic limit, spall, and shear strengths were investigated for incident pressures in the range 1-8 GPa, providing an insight into the response of this alloy under shock loading. Further, the time dependence of lateral stress behind the shock front was investigated to give an indication of material response.

Space Shuttle Projects

NASA Image and Video Library

1997-01-14

The crew patch for NASA's STS-83 mission depicts the Space Shuttle Columbia launching into space for the first Microgravity Sciences Laboratory 1 (MSL-1) mission. MSL-1 investigated materials science, fluid dynamics, biotechnology, and combustion science in the microgravity environment of space, experiments that were conducted in the Spacelab Module in the Space Shuttle Columbia's cargo bay. The center circle symbolizes a free liquid under microgravity conditions representing various fluid and materials science experiments. Symbolic of the combustion experiments is the surrounding starburst of a blue flame burning in space. The 3-lobed shape of the outermost starburst ring traces the dot pattern of a transmission Laue photograph typical of biotechnology experiments. The numerical designation for the mission is shown at bottom center. As a forerunner to missions involving International Space Station (ISS), STS-83 represented the hope that scientific results and knowledge gained during the flight will be applied to solving problems on Earth for the benefit and advancement of humankind.

Experimental and numerical investigations on melamine wedges.

PubMed

Schneider, S

2008-09-01

Melamine wedges are often used as acoustic lining material for anechoic chambers. It was proposed here to study the effects of the mounting conditions on the acoustic properties of the melamine wedges used in the large anechoic chamber at the LMA. The results of the impedance tube measurements carried out show that the mounting conditions must be taken into account when assessing the quality of an acoustic lining. As it can be difficult to simulate these mounting conditions in impedance tube experiments, a numerical method was developed, which can be used to complete the experiments or for parametric studies. By combining the finite and the boundary element method, it is possible to investigate acoustic linings with almost no restrictions as to the geometry, material behavior, or mounting conditions. The numerical method presented here was used to study the acoustic properties of the acoustic lining installed in the anechoic chamber at the LMA. Further experiments showed that the behavior of the melamine foam is anisotropic. Numerical simulations showed that this anisotropy can be used to advantage when designing an acoustic lining.

Investigation of Sensible and Latent Heat Storage System using various HTF

NASA Astrophysics Data System (ADS)

Beemkumar, N.; Karthikeyan, A.; Manoj, A.; Keerthan, J. S.; Stallan, Joseph Paul; Amithkishore, P.

2017-05-01

The objective of the work is investigating the latent heat storage system by varying heat transfer fluid (HTF). In this experiment, the effect of using different heat transfer fluids on the combined system is studied while using a low melting phase change material (PCM) i.e., paraffin wax. The heat transfer fluids chosen are water (low boiling fluid) and Therminol-66 (High boiling fluid). A comparison is made between the heat transfers by employing both the Heat transfer fluids. In the beginning, water is made to flow as the HTF and the charging process is undertaken followed by the discharging process by utilizing the different encapsulation materials namely, copper, aluminium and brass. These processes are then repeated for therminol-66 as HTF. At the end of the experiment it was concluded that even though therminol-66 enhances the latent heat storage capacity, water offers a higher sensible heat storage capacity, making it a better HTF for low melting PCM. Similar to above said process the experiments can be conducted for high and medium range melting point PCM with variation of HTF.

A pyrolysis study for the thermal and kinetic characteristics of an agricultural waste with two different plastic wastes.

PubMed

Çepelioğullar, Özge; Pütün, Ayşe E

2014-10-01

In this study, thermochemical conversion of plastic wastes (PET and PVC) together with an agricultural waste (hazelnut shell) was investigated. In order to determine the thermal and kinetic behaviours, pyrolysis experiments were carried out from room temperature to 800 °C, with a heating rate of 10 °C min(-1) in the presence of a N2 atmosphere in a thermogravimetric analyzer. With the obtained thermogravimetric data, an appropriate temperature was specified for the pyrolysis of biomass-plastic wastes in a fixed-bed reactor. At the second step, pyrolysis experiments were carried out at the same conditions with the thermogravimetric analyzer, except the final temperature which was up to 500 °C in this case. After pyrolysis experiments, pyrolysis yields were calculated and characterization studies for bio-oil were investigated. Experimental results showed that co-pyrolysis has an important role in the determination of the pyrolysis mechanism and the process conditions while designing/implementing a thermochemical conversion method where biomass-plastic materials were preferred as raw materials. © The Author(s) 2014.

Effects of acceleration rate on Rayleigh-Taylor instability in elastic-plastic materials

NASA Astrophysics Data System (ADS)

Banerjee, Arindam; Polavarapu, Rinosh

2016-11-01

The effect of acceleration rate in the elastic-plastic transition stage of Rayleigh-Taylor instability in an accelerated non-Newtonian material is investigated experimentally using a rotating wheel experiment. A non-Newtonian material (mayonnaise) was accelerated at different rates by varying the angular acceleration of a rotating wheel and growth patterns of single mode perturbations with different combinations of amplitude and wavelength were analyzed. Experiments were run at two different acceleration rates to compare with experiments presented in prior years at APS DFD meetings and the peak amplitude responses are captured using a high-speed camera. Similar to the instability acceleration, the elastic-plastic transition acceleration is found to be increasing with increase in acceleration rate for a given amplitude and wavelength. The experimental results will be compared to various analytical strength models and prior experimental studies using Newtonian fluids. Authors acknowledge funding support from Los Alamos National Lab subcontract(370333) and DOE-SSAA Grant (DE-NA0001975).

Experiment and density functional theory analyses of GdTaO4 single crystal

NASA Astrophysics Data System (ADS)

Ding, Shoujun; Kinross, Ashlie; Wang, Xiaofei; Yang, Huajun; Zhang, Qingli; Liu, Wenpeng; Sun, Dunlu

2018-05-01

GdTaO4 is a type of excellent materials that can be used as scintillation, laser matrix as well as self-activated phosphor has generated significant interest. Whereas its band structure, electronic structure and optical properties are still need elucidation. To solve this intriguing problem, high-quality GdTaO4 single crystal (M-type) was grown successfully using Czochralski method. Its structure as well as optical properties was determined in experiment. Moreover, a systematic theoretical calculation based on the density function theory methods were performed on M-type and M‧-type GdTaO4 and their band structure, density of state as well as optical properties were obtained. Combine with the performed experiment results, the calculated results were proved with high reliability. Hence, the calculated results obtained in this work could provide a deep understanding of GdTaO4 material, which also useful for the further investigation on GdTaO4 material.

The NASA Materials Science Research Program - It's New Strategic Goals and Plans

NASA Technical Reports Server (NTRS)

Schlagheck, Ronald A.

2003-01-01

In 2001, the NASA created a separate science enterprise, the Office of Biological and Physical Research (OBPR), to perform strategical and fundamental research bringing together physics, chemistry, biology, and engineering to solve problems needed for future agency mission goals. The Materials Science Program is one of basic research disciplines within this new Enterprise's Division of Physical Sciences Research. The Materials Science Program participates to utilize effective use of International Space Station (ISS) experimental facilities, target new scientific and technology questions, and transfer results for Earth benefits. The program has recently pursued new investigative research in areas necessary to expand NASA knowledge base for exploration of the universe, some of which will need access to the microgravity of space. The program has a wide variety of traditional ground and flight based research related types of basic science related to materials crystallization, fundamental processing, and properties characterization in order to obtain basic understanding of various phenomena effects and relationships to the structures, processing, and properties of materials. A summary of the types and sources for this research is presented and those experiments planned for the space. Areas to help expand the science basis for NASA future missions are described. An overview of the program is given including the scope of the current and future NASA Research Announcements with emphasis on new materials science initiatives. A description of the planned flight experiments to be conducted on the International Space Station program along with the planned facility class Materials Science Research Rack (MSRR) and Microgravity Glovebox (MSG) type investigations.

Environmental Verification Experiment for the Explorer Platform (EVEEP)

NASA Technical Reports Server (NTRS)

Norris, Bonnie; Lorentson, Chris

1992-01-01

Satellites and long-life spacecraft require effective contamination control measures to ensure data accuracy and maintain overall system performance margins. Satellite and spacecraft contamination can occur from either molecular or particulate matter. Some of the sources of the molecular species are as follows: mass loss from nonmetallic materials; venting of confined spacecraft or experiment volumes; exhaust effluents from attitude control systems; integration and test activities; and improper cleaning of surfaces. Some of the sources of particulates are as follows: leaks or purges which condense upon vacuum exposure; abrasion of movable surfaces; and micrometeoroid impacts. The Environmental Verification Experiment for the Explorer Platform (EVEEP) was designed to investigate the following aspects of spacecraft contamination control: materials selection; contamination modeling of existing designs; and thermal vacuum testing of a spacecraft with contamination monitors.

An investigation and conceptual design of a holographic starfield and landmark tracker

NASA Technical Reports Server (NTRS)

Welch, J. D.

1973-01-01

The analysis, experiments, and design effort of this study have supported the feasibility of the basic holographic tracker concept. Image intensifiers and photoplastic recording materials were examined, along with a Polaroid rapid process silver halide material. Two reference beam, coherent optical matched filter technique was used for multiplexing spatial frequency filters for starfields. A 1 watt HeNe laser and an electro-optical readout are also considered.

Evaluation of Natural Compounds for Antimicrobial Activity in the Introductory Microbiology Laboratory.

ERIC Educational Resources Information Center

Finer, Kim R.

1997-01-01

Presents an experiment that provides students with an opportunity to investigate folk medicine and herbal cures and their accompanying claims. Involves isolating some active compounds from plant materials and demonstrating their antibacterial activity. (JRH)

Outline of CS application experiments

NASA Astrophysics Data System (ADS)

Otsu, Y.; Kondoh, K.; Matsumoto, M.

1985-09-01

To promote and investigate the practical application of satellite use, CS application experiments for various social activity needs, including those of public services such as the National Police Agency and the Japanese National Railway, computer network services, news material transmissions, and advanced teleconference activities, were performed. Public service satellite communications systems were developed and tested. Based on results obtained, several public services have implemented CS-2 for practical disaster-back-up uses. Practical application computer network and enhanced video-conference experiments have also been performed.

Parts, materials, and processes experience summary, volume 2. [design, engineering, and quality control

NASA Technical Reports Server (NTRS)

1973-01-01

This summary provides the general engineering community with the accumulated experience from ALERT reports issued by NASA and the Government-Industry. Data Exchange Program, and related experience gained by Government and industry. It provides expanded information on selected topics by relating the problem area (failure) to the cause, the investigation and findings, the suggestions for avoidance (inspections, screening tests, proper part applications, requirements for manufacturer's plant facilities, etc.), and failure analysis procedures. Diodes, integrated circuits, and transistors are covered in this volume.

Experiment Requirements and Implementation Plan (ERIP) for semiconductor materials growth in low-G environment experiment no. MPS-77F087

NASA Technical Reports Server (NTRS)

Crouch, R. K.; Fripp, A. L.; Debnam, W. J.; Clark, I. O.

1981-01-01

Crystals of the intermetallic compound Pb1-xSnxTe will be grown in furnaces on the Space Shuttle. The reasons for conducting this growth in space, the program of investigation to develop the space experiment and the requirements that are placed on the Space Shuttle furnace are discussed. Also included are relevent thermophysical properties of Pb1-xSnxTe to the degree which they are known.

Scientific investigations at a lunar base

NASA Technical Reports Server (NTRS)

Duke, M. B.; Mendell, W. W.

1988-01-01

Scientific investigations to be carried out at a lunar base can have significant impact on the location, extent, and complexity of lunar surface facilities. Among the potential research activities to be carried out are: (1) Lunar Science: Studies of the origin and history of the Moon and early solar system, based on lunar field investigations, operation of networks of seismic and other instruments, and collection and analysis of materials; (2) Space Plasma Physics: Studies of the time variation of the charged particles of the solar wind, solar flares and cosmic rays that impact the Moon as it moves in and out of the magnetotail of the Earth; (3) Astronomy: Utilizing the lunar environment and stability of the surface to emplace arrays of astronomical instruments across the electromagnetic spectrum to improve spectral and spatial resolution by several orders of magnitude beyond the Hubble Space Telescope and other space observatories; (4) Fundamental physics and chemistry: Research that takes advantage of the lunar environment, such as high vacuum, low magnetic field, and thermal properties to carry out new investigations in chemistry and physics. This includes material sciences and applications; (5) Life Sciences: Experiments, such as those that require extreme isolation, highly sterile conditions, or very low natural background of organic materials may be possible; and (6) Lunar environmental science: Because many of the experiments proposed for the lunar surface depend on the special environment of the Moon, it will be necessary to understand the mechanisms that are active and which determine the major aspects of that environment, particularly the maintenance of high-vacuum conditions. From a large range of experiments, investigations and facilities that have been suggested, three specific classes of investigations are described in greater detail to show how site selection and base complexity may be affected: (1) Extended geological investigation of a complex region up to 250 kilometers from the base requires long range mobility, with transportable life support systems and laboratory facilities for the analysis of rocks and soil. Selection of an optimum base site would depend heavily on an evaluation of the degree to which science objectives could be met. These objectives could include lunar cratering, volcanism, resource surveys or other investigations; (2) An astronomical observatory initially instrumented with a VLF radio telescope, but later expanding to include other instruments, requires site preparation capability, "line shack" life support systems, instrument maintenance and storage facilities, and sortie mode transportation. A site perpetually shielded from Earth is optimum for the advanced stages of a lunar observatory; (3) an experimental physics laboratory conducting studies requiring high vacuum facilities and heavily instrumented experiments, is not highly dependent on lunar location, but will require much more flexibility in experiment operation and EVA capability, and more sophisticated instrument maintenance and fabrication facilities.

Final report for Assembling Microorganisms into Energy Converting Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sahin, Ozgur

The goal of this project was to integrate microorganisms capable of reversible energy transduction in response to changing relative humidity with non-biological materials to create hybrid energy conversion systems. While plants and many other biological organisms have developed structures that are extraordinarily effective in converting changes in relative humidity into mechanical energy, engineered energy transduction systems rarely take advantage of this powerful phenomenon. Rather than developing synthetic materials that can convert changes in relative humidity in to mechanical energy, we developed approaches to assemble bacterial spores into larger materials. These materials can convert energy from evaporation of water in drymore » atmospheric conditions, which we demonstrated by building energy harvesters from these materials. We have also developed experiments to investigate the interaction of water with the spore material, and to determine how this interaction imposes limits on energy conversion. In addition, we carried out theoretical calculations to investigate the limits imposed by the environmental conditions to the power available in the energy harvesting process. These calculations took into account heat and water vapor transfer in the atmosphere surrounding the spore based materials. Overall, our results suggest that biomolecular materials are promising candidates to convert energy from evaporation.« less

KSC-97PC1379

NASA Image and Video Library

1997-09-08

United States Microgravity Payload-4 (USMP-4) experiments are prepared to be flown on Space Shuttle mission STS-87 in the Space Station Processing Facility at Kennedy Space Center (KSC). Seen in the foreground at right is the Isothermal Dendritic Growth Experiment (IDGE), which will be used to study the dendritic solidification of molten materials in the microgravity environment. The metallic breadbox-like structure behind the IDGE is the Confined Helium Experiment (CHeX) that will study one of the basic influences on the behavior and properties of materials by using liquid helium confined between solid surfaces and microgravity. The large white vertical cylinder at left is the Advanced Automated Directional Solidification Furnace (AADSF) and the horizontal tube behind it is MEPHISTO, the French acronym for a cooperative American-French investigation of the fundamentals of crystal growth. Just below the left end of MEPHISTO is the Space Acceleration Measurement System, or SAMS, which measures the microgravity conditions in which the experiments are conducted. All of these experiments are scheduled for launch aboard STS-87 on Nov. 19 from KSC

Reaching Preferences in 11-Month-Old Infants: The Role of Objects' Material and Weight

ERIC Educational Resources Information Center

Paulus, Markus; Hauf, Petra

2012-01-01

Research in the past decades has investigated the time course of the acquisition of physical knowledge in early development in much detail. However, few is known about the motives that actually lead infants to interact with the objects of their physical world. The research presented here investigated in two experiments if 11-month-old infants'…

Investigating the Magnetic Interaction with Geomag and Tracker Video Analysis: Static Equilibrium and Anharmonic Dynamics

ERIC Educational Resources Information Center

Onorato, P.; Mascheretti, P.; DeAmbrosis, A.

2012-01-01

In this paper, we describe how simple experiments realizable by using easily found and low-cost materials allow students to explore quantitatively the magnetic interaction thanks to the help of an Open Source Physics tool, the Tracker Video Analysis software. The static equilibrium of a "column" of permanents magnets is carefully investigated by…

Nanosecond laser-metal ablation at different ambient conditions

NASA Astrophysics Data System (ADS)

Elsied, Ahmed M.; Dieffenbach, Payson C.; Diwakar, Prasoon K.; Hassanein, Ahmed

2018-05-01

Ablation of metals under different ambient conditions and laser fluences, was investigated through series of experiments. A 1064 nm, 6 ns Nd:YAG laser was used to ablate 1 mm thick metal targets with laser energy ranging from 2 mJ to 300 mJ. The experiments were designed to study the effect of material properties, laser fluence, ambient gas, and ambient pressure on laser-metal ablation. The first experiment was conducted under vacuum to study the effect of laser fluence and material properties on metal ablation, using a wide range of laser fluences (2 J/cm2 up to 300 J/cm2) and two different targets, Al and W. The second experiment was conducted at atmospheric pressure using two different ambient gases air and argon, to understand the effect of ambient gas on laser-metal ablation process. The third experiment was conducted at two different pressures (10 Torr and 760 Torr) using the same ambient gas to investigate the effect of ambient pressure on laser-metal ablation. To compare the different ablation processes, the amount of mass ablated, ablation depth, crater profile and melt formation were measured using White Light Profilometer (WLP). The experimental results show that at low laser fluence: the ablated mass, ablation depth, and height of molten layer follow a logarithmic function of the incident laser fluence. While, at high laser fluence they follow a linear function. This dependence on laser fluence was found to be independent on ambient conditions and irradiated material. The effect of ambient pressure was more pronounced than the effect of ambient gas type. Plasma shielding effect was found to be very pronounced in the presence of ambient gas and led to significant reduction in the total mass ablation.

Large strain dynamic compression for soft materials using a direct impact experiment

NASA Astrophysics Data System (ADS)

Meenken, T.; Hiermaier, S.

2006-08-01

Measurement of strain rate dependent material data of low density low strength materials like polymeric foams and rubbers still poses challenges of a different kind to the experimental set up. For instance, in conventional Split Hopkinson Pressure Bar tests the impedance mismatch between the bars and the specimen makes strain measurement almost impossible. Application of viscoelastic bars poses new problems with wave dispersion. Also, maximum achievable strains and strain rates depend directly on the bar lengths, resulting in large experimental set ups in order to measure relevant data for automobile crash applications. In this paper a modified SHPB will be presented for testing low impedance materials. High strains can be achieved with nearly constant strain rate. A thin film stress measurement has been applied to the specimen/bar interfaces to investigate the initial sample ring up process. The process of stress homogeneity within the sample was investigated on EPDM and PU rubber.

Research on simulation based material delivery system for an automobile company with multi logistics center

NASA Astrophysics Data System (ADS)

Luo, D.; Guan, Z.; Wang, C.; Yue, L.; Peng, L.

2017-06-01

Distribution of different parts to the assembly lines is significant for companies to improve production. Current research investigates the problem of distribution method optimization of a logistics system in a third party logistic company that provide professional services to an automobile manufacturing case company in China. Current research investigates the logistics leveling the material distribution and unloading platform of the automobile logistics enterprise and proposed logistics distribution strategy, material classification method, as well as logistics scheduling. Moreover, the simulation technology Simio is employed on assembly line logistics system which helps to find and validate an optimization distribution scheme through simulation experiments. Experimental results indicate that the proposed scheme can solve the logistic balance and levels the material problem and congestion of the unloading pattern in an efficient way as compared to the original method employed by the case company.

Optimizing soft X-ray NEXAFS spectroscopy in the laboratory

NASA Astrophysics Data System (ADS)

Mantouvalou, I.; Jonas, A.; Witte, K.; Jung, R.; Stiel, H.; Kanngießer, B.

2017-05-01

Near edge X-ray absorption fine structure (NEXAFS) spectroscopy in the soft X-ray range is feasible in the laboratory using laser-produced plasma sources. We present a study using seven different target materials for optimized data analysis. The emission spectra of the materials with atomic numbers ranging from Z = 6 to Z = 79 show distinct differences, rendering the adapted selection of a suitable target material for specialized experiments feasible. For NEXAFS spectroscopy a 112.5 nm thick polyimide film is investigated as a reference exemplifying the superiority of quasi-continuum like emission spectra.

Processing biobased polymers using plasticizers: Numerical simulations versus experiments

NASA Astrophysics Data System (ADS)

Desplentere, Frederik; Cardon, Ludwig; Six, Wim; Erkoç, Mustafa

2016-03-01

In polymer processing, the use of biobased products shows lots of possibilities. Considering biobased materials, biodegradability is in most cases the most important issue. Next to this, bio based materials aimed at durable applications, are gaining interest. Within this research, the influence of plasticizers on the processing of the bio based material is investigated. This work is done for an extrusion grade of PLA, Natureworks PLA 2003D. Extrusion through a slit die equipped with pressure sensors is used to compare the experimental pressure values to numerical simulation results. Additional experimental data (temperature and pressure data along the extrusion screw and die are recorded) is generated on a dr. Collin Lab extruder producing a 25mm diameter tube. All these experimental data is used to indicate the appropriate functioning of the numerical simulation tool Virtual Extrusion Laboratory 6.7 for the simulation of both the industrial available extrusion grade PLA and the compound in which 15% of plasticizer is added. Adding the applied plasticizer, resulted in a 40% lower pressure drop over the extrusion die. The combination of different experiments allowed to fit the numerical simulation results closely to the experimental values. Based on this experience, it is shown that numerical simulations also can be used for modified bio based materials if appropriate material and process data are taken into account.

Influence of Surface Texture and Roughness of Softer and Harder Counter Materials on Friction During Sliding

NASA Astrophysics Data System (ADS)

Menezes, Pradeep L.; Kishore; Kailas, Satish V.; Lovell, Michael R.

2015-01-01

Surface texture influences friction during sliding contact conditions. In the present investigation, the effect of surface texture and roughness of softer and harder counter materials on friction during sliding was analyzed using an inclined scratch testing system. In the experiments, two test configurations, namely (a) steel balls against aluminum alloy flats of different surface textures and (b) aluminum alloy pins against steel flats of different surface textures, are utilized. The surface textures were classified into unidirectionally ground, 8-ground, and randomly polished. For a given texture, the roughness of the flat surfaces was varied using grinding or polishing methods. Optical profilometer and scanning electron microscope were used to characterize the contact surfaces before and after the experiments. Experimental results showed that the surface textures of both harder and softer materials are important in controlling the frictional behavior. The softer material surface textures showed larger variations in friction between ground and polished surfaces. However, the harder material surface textures demonstrated a better control over friction among the ground surfaces. Although the effect of roughness on friction was less significant when compared to textures, the harder material roughness showed better correlations when compared to the softer material roughness.

Physical Properties of Granulates Used in Analogue Experiments of Caprock Failure and Sediment Remobilisation

NASA Astrophysics Data System (ADS)

Kukowski, N.; Warsitzka, M.; May, F.

2014-12-01

Geological systems consisting of a porous reservoir and a low-permeable caprock are prone to hydraulic fracturing, if pore pressure rises to the effective stress. Under certain conditions, hydraulic fracturing is associated with sediment remobilisation, e.g. sand injections or pipes, leading to reduced seal capacity of the caprock. In dynamically scaled analogue experiments using granular materials and air pressure, we intent to investigate strain patterns and deformation mechanisms during caprock failure and fluidisation of shallow over-pressured reservoirs. The aim of this study is to improve the understanding of leakage potential of a sealing formation and the fluidisation potential of a reservoir formation depending on rock properties and effective stress. For reliable interpretation of analogue experiments, physical properties of analogue materials, e.g. frictional strength, cohesion, density, permeability etc., have to be correctly scaled according to those of their natural equivalents. The simulation of caprock requires that the analogue material possess a low permeability and is capable to shear failure and tensional failure. In contrast, materials representing the reservoir have to possess high porosity and low shear strength. In order to find suitable analogue materials, we measured the stress-strain behaviour and the permeability of over 25 different types of natural and artificial granular materials, e.g. glass powder, siliceous microspheres, diatomite powder, loess, or plastic granulate. Here, we present data of frictional parameters, compressibility and permeability of these granular materials characterized as a function of sphericity, grain size, and density. The repertoire of different types of granulates facilitates the adjustment of accurate mechanical properties in the analogue experiments. Furthermore, conditions during seal failure and fluidisation can be examined depending on the wide range of varying physical properties.

The effect of iron on montmorillonite stability. (II) Experimental investigation

NASA Astrophysics Data System (ADS)

Wilson, James; Cressey, Gordon; Cressey, Barbara; Cuadros, Javier; Ragnarsdottir, K. Vala; Savage, David; Shibata, Masahiro

2006-01-01

Several designs proposed for high-level nuclear waste (HLW) repositories include steel waste canisters surrounded by montmorillonite clay. This work investigates montmorillonite stability in the presence of native Fe, magnetite and aqueous solutions under hydrothermal conditions. Two series of experiments were conducted. In the first, mixtures of Na-montmorillonite, magnetite, native Fe, calcite, and NaCl solutions were reacted at 250 °C, Psat for between 93 and 114 days. In the second series, the starting mixtures included Na-montmorillonite, native Fe and solutions of FeCl 2 which were reacted at temperatures of 80, 150, and 250 °C, Psat, for 90-92 days. Experiments were analysed using XRD, FT-IR, TEM, ICP-AES, and ICP-MS. In the first series of experiments, native Fe oxidised to produce magnetite and the starting montmorillonite material was transformed to Fe-rich smectite only when the Fe was added predominantly as Fe metal rather than Fe oxide (magnetite). The Fe-rich smectite was initially Fe(II)-rich, which oxidised to produce an Fe(III)-rich form on exposure to air. The expansion of this material on ethylene glycol solvation was much reduced compared to the montmorillonite starting material. TEM imaging shows that partial loss of tetrahedral sheets occurred during transformation of the montmorillonite, resulting in adjacent layers becoming H-bonded with a 7 Å repeat. The reduced swelling property of the Fe-smectite product may be due predominantly to the structural disruption of smectite layers and the formation of H-bonds. Solute activities corresponded to the approximate stability field calculated for hypothetical Fe(II)-saponite. In the second series of experiments, significant smectite alteration was only observed at 250 °C and the product contained a small proportion of a 7 Å repeat structure, observable by XRD. In these experiments, solute activities coincide with berthierine. The experiments indicate that although bentonite is still a desirable choice of backfill material for HLW repositories, some loss of expandability may result if montmorillonite is altered to Fe-rich smectite at the interface between steel canisters and bentonite.

Some results of the oxidation investigation of copper and silver samples flown on LDEF

NASA Technical Reports Server (NTRS)

Derooij, A.

1992-01-01

The Long Duration Exposure Facility (LDEF) Mission provides a unique opportunity to study the long term effects of the space environment on materials. The LDEF has been deployed in orbit on 7 April 1984 by the shuttle Challenger in an almost circular orbit with a mean altitude of 477 km and an inclination of 28.5 degrees. It was retrieved from its decayed orbit of 335 km by the shuttle Columbia on 12 January 1990 after almost 6 years in space. The LDEF is a 12-sided, 4.267 m diameter, and 9.144 m long structure. The experiments, placed on trays, are attached to the twelve sides and the two ends of the spacecraft. The LDEF was passively stabilized with one end of the spacecraft always pointing towards the earth center and one of the sides (row 9) always facing the flight direction. The materials investigated originate from the Ultra-Heavy Cosmic Ray Experiment (UHCRE). The main objective is a detailed study of the charge spectra of ultraheavy cosmic-ray nuclei from zinc to uranium and beyond, using solid-state track detectors. Besides the aluminium alloy used for the experiment, UHCRE comprises several other materials. The results of space exposure for two of them, the copper grounding strips and the thermal covers (FEP Teflon/Ag/Inconel) painted black on the inner side (Chemglaze Z306), are presented.

A scaling and experimental approach for investigating in-vessel cooling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henry, R.E.

1997-02-01

The TMI-2 accident experienced the relocation of a large quantity of core material to the lower plenum. The TMI-2 vessel investigation project concluded that approximately 20 metric tonnes of once molten fuel material drained into the RPV lower head. As a result, the lower head wall experienced a thermal transient that has been characterized as reaching temperatures as high as 1100{degrees}C, then a cooling transient with a rate of 10 to 100{degrees}C/min. Two mechanisms have been proposed as possible explanations for this cooling behavior. One is the ingression of water through core material as a result of interconnected cracks inmore » the frozen debris and/or water ingression around the crust which is formed on internal structures (core supports and in-core instrumentation) in the lower head. The second focuses on the lack of adhesion of oxidic core debris to the RPV wall when the debris contacts the wall. Furthermore, the potential for strain of the RPV lower head when the wall is overheated could provide for a significant cooling path for water to ingress between the RPV and the frozen core material next to the wall. To examine these proposed mechanisms, a set of scaled experiments have been developed to examine the potential for cooling. These are performed in a scaled system in which the high temperature molten material is iron termite and the RPV wall is carbon steel. A termite mass of 40 kg is used and the simulated reactor vessels have water in the lower head at pressures up to 2.2 MPa. Furthermore, two different thicknesses of the vessel wall are examined with the thicker vessel having virtually no potential for material creep during the experiment and the thinner wall having the potential for substantial creep. Moreover, the experiment includes the option of having molten iron as the first material to drain into the RPV lower head or molten aluminum oxide being the only material that drains into the test configuration.« less

Salt efflorescence due to water-rock interaction on the surface of tuff cave in the Yoshimi-Hyakuana Historic Site, central Japan

NASA Astrophysics Data System (ADS)

Oguchi, Chiaki T.; Kodama, Shogo; Mohammad, Rajib; Tharanga Udagedara, Dashan

2016-04-01

Artificial cave walls in Yoshimi Hyakuana Historic Site have been suffering from salt weathering since 1945 when the caves were made. To consider the processes of weathering and subsequent crystallization of secondary minerals, water-rock experiment using tuff from this area was performed. Rocks, surface altered materials, groundwater and rainwater were collected, and chemical and mineralogical characteristics of those samples were investigated. The XRD and SEM-EDS analyses were carried out for the solid samples and ICP-OES analysis was performed for the solution generated from the experiment, groundwater and rainwater. Gypsum is detected in original tuff, and on grey and whiter coloured altered materials. General chemical changes were observed on this rock. However, it is found that purple and black altered materials were mainly made due to microbiological processes.

Experimental investigation of refractory metals in the premelting region during fast heating

NASA Astrophysics Data System (ADS)

Senchenko, V. N.; Belikov, R. S.; Popov, V. S.

2015-11-01

This work demonstrates experimental possibility of investigation of high refractory materials around its melting point, particularly in premelting region with high accuracy. In this article authors describe the developed experimental setup based on rapid resistive self-heating of a sample by a large current pulse generated by a capacitor discharge circuit that allow fast pulse interruption by temperature feedback signal. The sample temperature was measured with a two-channel microsecond radiation pyrometer. Preliminary experiments were conducted on tantalum and molybdenum at heating speed of 108 K/s. The method allows investigating thermophysical properties of refractory conductive materials such as melting temperature, melting heat, specific resistivity, specific enthalpy and specific heat capacity in solid and liquid phase, especially in premelting area.

Investigation of Low Heat Accumulation Asphalt Mixture and Its Impact on Urban Heat Environment

PubMed Central

Xie, Jianguang; Yang, Zhaoxu; Liang, Leilei

2015-01-01

This study is focused on investigating the effectiveness of low heat accumulation asphalt mixture and its impact on the urban heat environment. Infrared radiation experiments showed that the temperature of the asphalt mixture decreased with the increase in far-infrared radiant material. The results also revealed that, compared to asphalt with 0% far-infrared radiant content, the asphalt material with a certain ratio of far-infrared radiation material had higher stability at high and low temperatures as well as good water absorption capacity. The Marshall stability of the specimen mixed with 6% far-infrared radiant was higher by 12.2% and had a residual stability of up to 98.9%. Moreover, the low-temperature splitting tensile strength of the asphalt mixture with 6% far-infrared radiation material increased by 21.3%. The friction coefficient of the asphalt mixtures with 6% and 12% far-infrared radiation material increased by 17.7% and 26.9%, respectively. PMID:26222762

Investigation of Low Heat Accumulation Asphalt Mixture and Its Impact on Urban Heat Environment.

PubMed

Xie, Jianguang; Yang, Zhaoxu; Liang, Leilei

2015-01-01

This study is focused on investigating the effectiveness of low heat accumulation asphalt mixture and its impact on the urban heat environment. Infrared radiation experiments showed that the temperature of the asphalt mixture decreased with the increase in far-infrared radiant material. The results also revealed that, compared to asphalt with 0% far-infrared radiant content, the asphalt material with a certain ratio of far-infrared radiation material had higher stability at high and low temperatures as well as good water absorption capacity. The Marshall stability of the specimen mixed with 6% far-infrared radiant was higher by 12.2% and had a residual stability of up to 98.9%. Moreover, the low-temperature splitting tensile strength of the asphalt mixture with 6% far-infrared radiation material increased by 21.3%. The friction coefficient of the asphalt mixtures with 6% and 12% far-infrared radiation material increased by 17.7% and 26.9%, respectively.

Project Explorer's unique experiments: Get Away Special #007

NASA Technical Reports Server (NTRS)

Henderson, A. J., Jr.

1986-01-01

The Project Explorer payload represents the first attempt at broadcasting digitized voice signals via a Space Shuttle flight on amateur radio frequencies. These amateur ham-radio frequencies will be transmitting real time data while the experiments are operating. Experiments 1, 2, and 3 represent the work of students ranging from materials processing to the science of biology. Experiment 1 will study the solidification of two hypereutectic alloys, lead-antimony and aluminum-copper. Experiment 2 will investigate the examination and growth of radish seeds in space. Experiment 3 will examine the electrochemical growth process of potassium tetrocyonoplatinate hydrate crystals and Experiment 4 involves amateur radio transmissions, monitoring and support of the entire Get Away Special (GAS) 007 payload.

The materials irradiation experiment for testing plasma facing materials at fusion relevant conditions

DOE PAGES

Garrison, L. M.; Zenobia, Samuel J.; Egle, Brian J.; ...

2016-08-01

The Materials Irradiation Experiment (MITE-E) was constructed at the University of Wisconsin-Madison Inertial Electrostatic Confinement Laboratory to test materials for potential use as plasma-facing materials (PFMs) in fusion reactors. PFMs in fusion reactors will be bombarded with x-rays, neutrons, and ions of hydrogen and helium. More needs to be understood about the interactions between the plasma and the materials to validate their use for fusion reactors. The MITE-E simulates some of the fusion reactor conditions by holding samples at temperatures up to 1000°C while irradiating them with helium or deuterium ions with energies from 10 to 150 keV. The ionmore » gun can irradiate the samples with ion currents of 20 μA–500 μA; the typical current used is 72 μA, which is an average flux of 9 × 10 14 ions/(cm 2 s). The ion gun uses electrostatic lenses to extract and shape the ion beam. A variable power (1-20 W), steady-state, Nd:YAG laser provides additional heating to maintain a constant sample temperature during irradiations. The ion beam current reaching the sample is directly measured and monitored in real-time during irradiations. The ion beam profile has been investigated using a copper sample sputtering experiment. In conclusion, the MITE-E has successfully been used to irradiate polycrystalline and single crystal tungsten samples with helium ions and will continue to be a source of important data for plasma interactions with materials.« less

The materials irradiation experiment for testing plasma facing materials at fusion relevant conditions.

PubMed

Garrison, L M; Zenobia, S J; Egle, B J; Kulcinski, G L; Santarius, J F

2016-08-01

The Materials Irradiation Experiment (MITE-E) was constructed at the University of Wisconsin-Madison Inertial Electrostatic Confinement Laboratory to test materials for potential use as plasma-facing materials (PFMs) in fusion reactors. PFMs in fusion reactors will be bombarded with x-rays, neutrons, and ions of hydrogen and helium. More needs to be understood about the interactions between the plasma and the materials to validate their use for fusion reactors. The MITE-E simulates some of the fusion reactor conditions by holding samples at temperatures up to 1000 °C while irradiating them with helium or deuterium ions with energies from 10 to 150 keV. The ion gun can irradiate the samples with ion currents of 20 μA-500 μA; the typical current used is 72 μA, which is an average flux of 9 × 10(14) ions/(cm(2) s). The ion gun uses electrostatic lenses to extract and shape the ion beam. A variable power (1-20 W), steady-state, Nd:YAG laser provides additional heating to maintain a constant sample temperature during irradiations. The ion beam current reaching the sample is directly measured and monitored in real-time during irradiations. The ion beam profile has been investigated using a copper sample sputtering experiment. The MITE-E has successfully been used to irradiate polycrystalline and single crystal tungsten samples with helium ions and will continue to be a source of important data for plasma interactions with materials.

The materials irradiation experiment for testing plasma facing materials at fusion relevant conditions

NASA Astrophysics Data System (ADS)

Garrison, L. M.; Zenobia, S. J.; Egle, B. J.; Kulcinski, G. L.; Santarius, J. F.

2016-08-01

The Materials Irradiation Experiment (MITE-E) was constructed at the University of Wisconsin-Madison Inertial Electrostatic Confinement Laboratory to test materials for potential use as plasma-facing materials (PFMs) in fusion reactors. PFMs in fusion reactors will be bombarded with x-rays, neutrons, and ions of hydrogen and helium. More needs to be understood about the interactions between the plasma and the materials to validate their use for fusion reactors. The MITE-E simulates some of the fusion reactor conditions by holding samples at temperatures up to 1000 °C while irradiating them with helium or deuterium ions with energies from 10 to 150 keV. The ion gun can irradiate the samples with ion currents of 20 μA-500 μA; the typical current used is 72 μA, which is an average flux of 9 × 1014 ions/(cm2 s). The ion gun uses electrostatic lenses to extract and shape the ion beam. A variable power (1-20 W), steady-state, Nd:YAG laser provides additional heating to maintain a constant sample temperature during irradiations. The ion beam current reaching the sample is directly measured and monitored in real-time during irradiations. The ion beam profile has been investigated using a copper sample sputtering experiment. The MITE-E has successfully been used to irradiate polycrystalline and single crystal tungsten samples with helium ions and will continue to be a source of important data for plasma interactions with materials.

Physics of Colloids in Space (PCS) Flight Hardware Developed

NASA Technical Reports Server (NTRS)

Koudelka, John M.

2001-01-01

investigation that will be located in an Expedite the Process of Experiments to Space Station (EXPRESS) Rack. The investigation will be conducted in the International Space Station U.S. laboratory, Destiny, over a period of approximately 10 months during the station assembly period from flight 6A through flight UF-2. This experiment will gather data on the basic physical properties of colloids by studying three different colloid systems with the objective of understanding how they grow and what structures they form. A colloidal suspension consists of fine particles (micrometer to submicrometer) suspended in a fluid for example, paints, milk, salad dressings, and aerosols. The long-term goal of this investigation is to learn how to steer the growth of colloidal suspensions to create new materials and new structures. This experiment is part of a two-stage investigation conceived by Professor David Weitz of Harvard University along with Professor Peter Pusey of the University of Edinburgh. The experiment hardware was developed by the NASA Glenn Research Center through contracts with Dynacs, Inc., and ZIN Technologies.

Mechanics of Granular Materials (MGM) Test Cell

NASA Technical Reports Server (NTRS)

2004-01-01

Test cells comprise specimen sand contained in a latex membrane (with a grid pattern for CCD cameras) between metal end plates and housed in a water-filled Lexan jacket. Experiment flown on STS-79 and STS-89. Principal Investigator: Dr. Stein Sture.

A Safe Lab on Nerve Gases.

ERIC Educational Resources Information Center

Tucker, David C.

1988-01-01

Describes an experiment involving pineapples and gelatin that allows students to investigate the conditions that typically render an enzyme functionless, similar to the effect of nerve gasses. Discusses the materials, procedures, and results, drawing analogies to the effects of a nerve gas. (CW)

A Rolling Sphere on a Tilted Rotating Turntable.

ERIC Educational Resources Information Center

Sambles, J. R.; And Others

1983-01-01

Describes an advanced high school/college experiment that illustrates the mechanics describing the motion of a rolling ball. Includes procedures used, discussions of vectoral and mathematical (calculus) solutions to the investigation, and sample student results using the recommended materials. (JM)

Investigations into the mechanism of material removal and surface modification at atomic scale on stainless steel using molecular dynamics simulation

NASA Astrophysics Data System (ADS)

Ranjan, Prabhat; Balasubramaniam, R.; Jain, V. K.

2018-06-01

A molecular dynamics simulation (MDS) has been carried out to investigate the material removal phenomenon of chemo-mechanical magnetorheological finishing (CMMRF) process. To understand the role of chemical assisted mechanical abrasion in CMMRF process, material removal phenomenon is subdivided into three different stages. In the first stage, new atomic bonds viz. Fe-O-Si is created on the surface of the workpiece (stainless steel). The second stage deals with the rupture of parent bonds like Fe-Fe on the workpiece. In the final stage, removal of material from the surface in the form of dislodged debris (cluster of atoms) takes place. Effects of process parameters like abrasive particles, depth of penetration and initial surface condition on finishing force, potential energy (towards secondary phenomenon such as chemical instability of the finished surface) and material removal at atomic scale have been investigated. It was observed that the type of abrasive particle is one of the important parameters to produce atomically smooth surface. Experiments were also conducted as per the MDS to generate defect-free and sub-nanometre-level finished surface (Ra value better than 0.2 nm). The experimental results reasonably agree well with the simulation results.

Research experiences on materials science in space aboard Salyut and Mir

NASA Technical Reports Server (NTRS)

Regel, Liya L.

1992-01-01

From 1980 through 1991 approximately 500 materials processing experiments were performed aboard the space stations Salyut 6, Salyut 7 and Mir. This includes work on catalysts, polymers, metals and alloys, optical materials, superconductors, electronic crystals, thin film semiconductors, super ionic crystals, ceramics, and protein crystals. Often the resulting materials were surprisingly superior to those prepared on earth. The Soviets were the first to fabricate a laser (CdS) from a crystal grown in space, the first to grow a heterostructure in space, the first super ionic crystal in space, the first crystals of CdTe and its alloys, the first zeolite crystals, the first protein crystals, the first chromium disilicide glass, etc. The results were used to optimize terrestrial materials processing operations in Soviet industry. The characteristics of these three space stations are reviewed, along with the advantages of a space station for materials research, and the problems encountered by the materials scientists who used them. For example, the stations and the materials processing equipment were designed without significant input from the scientific community that would be using them. It is pointed out that successful results have been achieved also by materials processing at high gravity in large centrifuges. This research is also continuing around the world, including at Clarkson University. It is recommended that experiments be conducted in centrifuges in space, in order to investigate the acceleration regime between earth's gravity and the microgravity achieved in orbiting space stations. One cannot expect to understand the influence of gravity on materials processing from only two data points, earth's gravity and microgravity. One must also understand the influence of fluctuations in acceleration on board space stations, the so-called 'g-jitter.' This paper is presented in outline and graphical form.

Near Mbar-Level Dynamic Loading of Materials by Direct Laser-Irradiation

NASA Astrophysics Data System (ADS)

Tierney, T. E.; Swift, D. C.; Gammel, J. T.; Luo, S.; Johnson, R. P.

2003-12-01

We are developing techniques to perform direct-laser-illumination-driven, dynamic materials experiments at up to Mbar pressures with use of the Trident Laser Laboratory at Los Alamos. By temporally controlling the laser-irradiance, we are able to shape our loading for studies of fast-rise shocks, precursors, or isentropic compression. Laser-driven shock experiments are advantageous when considering the efficiency (fast turnaround), relative ease of sample recovery, taylorable dynamic loading, and in-situ structure diagnostics. Frequently, these experiments last 1-5 nanoseconds, and thus, permit investigation of rate-dependent processes and high strain rate environments. Laser-driven dynamic experiments are an important complement to traditional dynamic (e.g., light-gas gun) and static (e.g., diamond-anvil cell) experiments with certain advantages in studying equation of state, phase transitions and mechanical-chemical properties of Earth and planetary materials. Understanding high-pressure behavior in this regime is critical to phase boundaries for planetary interiors and dynamic properties of impact processes. Although we have studied silicates, oxides, metals, alloys and organic materials, this paper will focus on shocked and isentropically-compressed results obtained for iron in the range of 10-70 GPa (0.1-0.7 Mbar). Free surface velocities are measured using a Velocity Interferometer System for Any Reflector (VISAR). Nanosecond-scale laser experiments were interpreted with careful attention to exaggerated elastic-plastic effects and using accurate new equations of state for the phases of iron. This poster will present our technique, experimental results, and interpretation. *Work performed under the auspices of the US DOE under contract No. W-7405-ENG-36.

S3 targets monitoring with an electron gun

NASA Astrophysics Data System (ADS)

Kallunkathariyil, J.; Stodel, Ch.; Marry, C.; Frémont, G.; Bastin, B.; Piot, J.; Clément, E.; Le Moal, S.; Morel, V.; Thomas, J.-C.; Kamalou, O.; Spitaëls, C.; Savajols, H.; Vostinar, M.; Pellemoine, F.; Mittig, W.

2018-05-01

The monitoring of targets under irradiation was investigated using a 20 keV electron beam. An integrated and automated electron beam deflection was developed allowing a monitoring over the whole surface of target materials. Thus, local defects could be identified on-line during an experiment performed at GANIL involving different materials irradiated with a focused krypton beam at 10.5 MeV/u. Performances of this target monitoring system are presented in this paper.

In situ transmission electron microscopy He + implantation and thermal aging of nanocrystalline iron

DOE PAGES

Muntifering, Brittany R.; Fang, Youwu; Leff, Asher C.; ...

2016-10-04

Due to their high density of interfaces, nanostructured material are hypothesized to show a higher tolerance to radiation damage compared to conventional coarse-grained materials and are on interest for use in future nuclear reactors. In order to investigate the roles of vacancies, self-interstitials, and helium during defect accumulation, and the thermal evolution of such defects, a complex set of in situ TEM experiments were performed in nanocrystalline iron.

Wiseman conducts BCAT-C1 experiment

NASA Image and Video Library

2014-07-25

ISS040-E-076505 (25 July 2014) --- NASA astronaut Reid Wiseman, Expedition 40 flight engineer, conducts a session with the Binary Colloidal Alloy Test-C1, or BCAT-C1, experiment in the Kibo laboratory of the International Space Station. Results from this ongoing investigation of colloids ? mixtures of small particles distributed throughout a liquid ? will help materials scientists to develop new consumer products with unique properties and longer shelf lives.

Wiseman conducts BCAT-C1 experiment

NASA Image and Video Library

2014-07-25

ISS040-E-076510 (25 July 2014) --- NASA astronaut Reid Wiseman, Expedition 40 flight engineer, conducts a session with the Binary Colloidal Alloy Test-C1, or BCAT-C1, experiment in the Kibo laboratory of the International Space Station. Results from this ongoing investigation of colloids ? mixtures of small particles distributed throughout a liquid ? will help materials scientists to develop new consumer products with unique properties and longer shelf lives.

Wiseman conducts BCAT-C1 experiment

NASA Image and Video Library

2014-07-25

ISS040-E-076507 (25 July 2014) --- NASA astronaut Reid Wiseman, Expedition 40 flight engineer, conducts a session with the Binary Colloidal Alloy Test-C1, or BCAT-C1, experiment in the Kibo laboratory of the International Space Station. Results from this ongoing investigation of colloids ? mixtures of small particles distributed throughout a liquid ? will help materials scientists to develop new consumer products with unique properties and longer shelf lives.

Analysis and Simulation of Far-Field Seismic Data from the Source Physics Experiment

DTIC Science & Technology

2012-09-01

ANALYSIS AND SIMULATION OF FAR-FIELD SEISMIC DATA FROM THE SOURCE PHYSICS EXPERIMENT Arben Pitarka, Robert J. Mellors, Arthur J. Rodgers, Sean...Security Site (NNSS) provides new data for investigating the excitation and propagation of seismic waves generated by buried explosions. A particular... seismic model. The 3D seismic model includes surface topography. It is based on regional geological data, with material properties constrained by shallow

Remote Atomic Force Microscopy of Microscopic Organisms: Technological Innovations for Hands-On Science with Middle and High School Students

ERIC Educational Resources Information Center

Jones, M. G.; Andre, T.; Kubasko, D.; Bokinsky, A.; Tretter, T.; Negishi, A.; Taylor, R.; Superfine, R.

2004-01-01

This study examined hands-on experiences in the context of an investigation of viruses and explored how and why hands-on experiences may be effective. We sought to understand whether or not touching and manipulating materials and objects could lead to a deeper, more effective type of knowing than that we obtain from sight or sound alone. Four…

Age of acquisition affects the retrieval of grammatical category information.

PubMed

Bai, Lili; Ma, Tengfei; Dunlap, Susan; Chen, Baoguo

2013-01-01

This study investigated age of acquisition (AoA) effects on processing grammatical category information of Chinese single-character words. In Experiment 1, nouns and verbs that were acquired at different ages were used as materials in a grammatical category decision task. Results showed that the grammatical category information of earlier acquired nouns and verbs was easier to retrieve. In Experiment 2, AoA and predictability from orthography to grammatical category were manipulated in a grammatical category decision task. Results showed larger AoA effects under lower predictability conditions. In Experiment 3, a semantic category decision task was used with the same materials as those in Experiment 2. Different results were found from Experiment 2, suggesting that the grammatical category decision task is not merely the same as the semantic category decision task, but rather involves additional processing of grammatical category information. Therefore the conclusions of Experiments 1 and 2 were strengthened. In summary, it was found for the first time that AoA affects the retrieval of grammatical category information, thus providing new evidence in support of the arbitrary mapping hypothesis.

Laser welding of polypropylene using two different sources

NASA Astrophysics Data System (ADS)

Mandolfino, Chiara; Brabazon, Dermot; McCarthy, Éanna; Lertora, Enrico; Gambaro, Carla; Ahad, Inam Ul

2017-10-01

In this paper, laser weldability of neutral polypropylene has been investigated using fibre and carbon dioxide lasers. A design of experiment (DoE) was conducted in order to establish the influence of the main working parameters on the welding strength of the two types of laser. The welded samples were characterized by carrying out visual and microscopic inspection for the welding morphology and cross-section, and by distinguishing the tensile strength. The resulting weld quality was investigated by means of optical microscopy at weld cross-sections. The tensile strength of butt-welded materials was measured and compared to that of a corresponding bulk material.

Study of Vacuum Energy Physics for Breakthrough Propulsion

NASA Technical Reports Server (NTRS)

Millis, Marc G. (Technical Monitor); Maclay, G. Jordan; Hammer, Jay; Clark, Rod; George, Michael; Kim, Yeong; Kir, Asit

2004-01-01

This report summarizes the accomplishments during a three year research project to investigate the use of surfaces, particularly in microelectromechanical systems (MEMS), to exploit quantum vacuum forces. During this project, we developed AFM instrumentation to repeatably measure Casimir forces in the nanoNewton range at 10 6 torr, designed an experiment to measure attractive and repulsive quantum vacuum forces, developed a QED based theory of Casimir forces that includes non-ideal material properties for rectangular cavities and for multilayer slabs, developed theoretical models for a variety of microdevices utilizing vacuum forces, applied vacuum physics to a gedanken spacecraft, and investigated a new material with a negative index of refraction.

Characterizing and modeling the free recovery and constrained recovery behavior of a polyurethane shape memory polymer

PubMed Central

Volk, Brent L; Lagoudas, Dimitris C; Maitland, Duncan J

2011-01-01

In this work, tensile tests and one-dimensional constitutive modeling are performed on a high recovery force polyurethane shape memory polymer that is being considered for biomedical applications. The tensile tests investigate the free recovery (zero load) response as well as the constrained displacement recovery (stress recovery) response at extension values up to 25%, and two consecutive cycles are performed during each test. The material is observed to recover 100% of the applied deformation when heated at zero load in the second thermomechanical cycle, and a stress recovery of 1.5 MPa to 4.2 MPa is observed for the constrained displacement recovery experiments. After performing the experiments, the Chen and Lagoudas model is used to simulate and predict the experimental results. The material properties used in the constitutive model – namely the coefficients of thermal expansion, shear moduli, and frozen volume fraction – are calibrated from a single 10% extension free recovery experiment. The model is then used to predict the material response for the remaining free recovery and constrained displacement recovery experiments. The model predictions match well with the experimental data. PMID:22003272

Galactic cosmic ray abundances and spectra behind defined shielding.

PubMed

Heinrich, W; Benton, E V; Wiegel, B; Zens, R; Rusch, G

1994-10-01

LET spectra have been measured for lunar missions and for several near Earth orbits ranging from 28 degrees to 83 degrees inclination. In some of the experiments the flux of GCR was determined separately from contributions caused by interactions in the detector material. Results of these experiments are compared to model calculations. The general agreement justifies the use of the model to calculate GCR fluxes. The magnitude of variations caused by solar modulation, geomagnetic shielding, and shielding by matter determined from calculated LET spectra is generally in agreement with experimental data. However, more detailed investigations show that there are some weak points in modeling solar modulation and shielding by material. These points are discussed in more detail.

Damping Experiment of Spinning Composite Plates With Embedded Viscoelastic Material

NASA Technical Reports Server (NTRS)

Mehmed, Oral

1998-01-01

One way to increase gas turbine engine blade reliability and durability is to reduce blade vibration. It is well known that vibration can be reduced by adding damping to metal and composite blade-disk systems. As part of a joint research effort of the NASA Lewis Research Center and the University of California, San Diego, the use of integral viscoelastic damping treatment to reduce the vibration of rotating composite fan blades was investigated. The objectives of this experiment were to verify the structural integrity of composite plates with viscoelastic material patches embedded between composite layers while under large steady forces from spinning, and to measure the damping and natural frequency variation with rotational speed.

Around Marshall

NASA Image and Video Library

1992-09-12

The science laboratory, Spacelab-J (SL-J), flown aboard the STS-47 flight was a joint venture between NASA and the National Space Development Agency of Japan (NASDA) utilizing a manned Spacelab module. The mission conducted 24 materials science and 20 life science experiments, of which 35 were sponsored by NASDA, 7 by NASA, and two collaborative efforts. Materials science investigations covered such fields as biotechnology, electronic materials, fluid dynamics and transport phenomena, glasses and ceramics, metals and alloys, and acceleration measurements. Life sciences included experiments on human health, cell separation and biology, developmental biology, animal and human physiology and behavior, space radiation, and biological rhythms. Test subjects included the crew, Japanese koi fish (carp), cultured animal and plant cells, chicken embryos, fruit flies, fungi and plant seeds, and frogs and frog eggs. Featured together in the Science Operation Area (SOA) are payload specialists’ first Materials Processing Test during NASA/NASDA joint ground activities at the Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at Marshall Space Flight Center (MSFC).

Around Marshall

NASA Image and Video Library

1992-09-12

The science laboratory, Spacelab-J (SL-J), flown aboard the STS-47 flight was a joint venture between NASA and the National Space Development Agency of Japan (NASDA) utilizing a manned Spacelab module. The mission conducted 24 materials science and 20 life science experiments, of which 35 were sponsored by NASDA, 7 by NASA, and two collaborative efforts. Materials science investigations covered such fields as biotechnology, electronic materials, fluid dynamics and transport phenomena, glasses and ceramics, metals and alloys, and acceleration measurements. Life sciences included experiments on human health, cell separation and biology, developmental biology, animal and human physiology and behavior, space radiation, and biological rhythms. Test subjects included the crew, Japanese koi fish (carp), cultured animal and plant cells, chicken embryos, fruit flies, fungi and plant seeds, and frogs and frog eggs. Featured together in the Science Operation Area (SOA) are payload specialists’ first Materials Processing Test during NASA/NASDA joint ground activities at the Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at Marshall Space Fight Center (MSFC).

Haptic identification of objects and their depictions.

PubMed

Klatzky, R L; Loomis, J M; Lederman, S J; Wake, H; Fujita, N

1993-08-01

Haptic identification of real objects is superior to that of raised two-dimensional (2-D) depictions. Three explanations of real-object superiority were investigated: contribution of material information, contribution of 3-D shape and size, and greater potential for integration across the fingers. In Experiment 1, subjects, while wearing gloves that gently attenuated material information, haptically identified real objects that provided reduced cues to compliance, mass, and part motion. The gloves permitted exploration with free hand movement, a single outstretched finger, or five outstretched fingers. Performance decreased over these three conditions but was superior to identification of pictures of the same objects in all cases, indicating the contribution of 3-D structure and integration across the fingers. Picture performance was also better with five fingers than with one. In Experiment 2, the subjects wore open-fingered gloves, which provided them with material information. Consequently, the effect of type of exploration was substantially reduced but not eliminated. Material compensates somewhat for limited access to object structure but is not the primary basis for haptic object identification.

Installing Mechanics of Granular Materials (MGM) Experiment Test Cell

NASA Technical Reports Server (NTRS)

1996-01-01

Astronaut Carl Walz installs Mechanics of Granular Materials (MGM) test cell on STS-79. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditons that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: NASA/John Space Center

Space Weathering Experiments on Spacecraft Materials

NASA Technical Reports Server (NTRS)

Engelhart, D. P.; Cooper, R.; Cowardin, H.; Maxwell, J.; Plis, E.; Ferguson, D.; Barton, D.; Schiefer, S.; Hoffmann, R.

2017-01-01

A project to investigate space environment effects on specific materials with interest to remote sensing was initiated in 2016. The goal of the project is to better characterize changes in the optical properties of polymers found in multi-layered spacecraft insulation (MLI) induced by electron bombardment. Previous analysis shows that chemical bonds break and potentially reform when exposed to high energy electrons like those seen in orbit. These chemical changes have been shown to alter a material's optical reflectance, among other material properties. This paper presents the initial experimental results of MLI materials exposed to various fluences of high energy electrons, designed to simulate a portion of the geosynchronous Earth orbit (GEO) space environment. It is shown that the spectral reflectance of some of the tested materials changes as a function of electron dose. These results provide an experimental benchmark for analysis of aging effects on satellite systems which can be used to improve remote sensing and space situational awareness. They also provide preliminary analysis on those materials that are most likely to comprise the high area-to-mass ratio (HAMR) population of space debris in the geosynchronous orbit environment. Finally, the results presented in this paper serve as a proof of concept for simulated environmental aging of spacecraft polymers that should lead to more experiments using a larger subset of spacecraft materials.

Application of CaO-Based Bed Material for Dual Fluidized Bed Steam Biomass Gasification

NASA Astrophysics Data System (ADS)

Koppatz, S.; Pfeifer, C.; Kreuzeder, A.; Soukup, G.; Hofbauer, H.

Gasification of biomass is a suitable option for decentralized energy supply based on renewable sources in the range of up to 50 MW fuel input. The paper presents the dual fluidized bed (DFB) steam gasification process, which is applied to generate high quality and nitrogen-free product gas. Essential part of the DFB process is the bed material used in the fluidized reactors, which has significant impact on the product gas quality. By the use of catalytically active bed materials the performance of the overall process is increased, since the bed material favors reactions of the steam gasification. In particular, tar reforming reactions are favored. Within the paper, the pilot plant based on the DFB process with 100kW fuel input at Vienna University of Technology, Austria is presented. Actual investigations with focus on CaO-based bed materials (limestone) as well as with natural olivine as bed material were carried out at the pilot plant. The application of CaO-based bed material shows mainly decreased tar content in the product gas in contrast to experiments with olivine as bed material. The paper presents the results of steam gasification experiments with limestone and olivine, whereby the product gas composition as well as the tar content and the tar composition are outlined.

First Materials Processing Test in the Science Operation Area (SOA) During STS-47 Spacelab-J Mission

NASA Technical Reports Server (NTRS)

1992-01-01

The science laboratory, Spacelab-J (SL-J), flown aboard the STS-47 flight was a joint venture between NASA and the National Space Development Agency of Japan (NASDA) utilizing a manned Spacelab module. The mission conducted 24 materials science and 20 life science experiments, of which 35 were sponsored by NASDA, 7 by NASA, and two collaborative efforts. Materials science investigations covered such fields as biotechnology, electronic materials, fluid dynamics and transport phenomena, glasses and ceramics, metals and alloys, and acceleration measurements. Life sciences included experiments on human health, cell separation and biology, developmental biology, animal and human physiology and behavior, space radiation, and biological rhythms. Test subjects included the crew, Japanese koi fish (carp), cultured animal and plant cells, chicken embryos, fruit flies, fungi and plant seeds, and frogs and frog eggs. Featured together in the Science Operation Area (SOA) are payload specialists' first Materials Processing Test during NASA/NASDA joint ground activities at the Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at Marshall Space Fight Center (MSFC).

First Materials Processing Test in the Science Operation Area (SOA) During STS-47 Spacelab-J Mission

NASA Technical Reports Server (NTRS)

1992-01-01

The science laboratory, Spacelab-J (SL-J), flown aboard the STS-47 flight was a joint venture between NASA and the National Space Development Agency of Japan (NASDA) utilizing a manned Spacelab module. The mission conducted 24 materials science and 20 life science experiments, of which 35 were sponsored by NASDA, 7 by NASA, and two collaborative efforts. Materials science investigations covered such fields as biotechnology, electronic materials, fluid dynamics and transport phenomena, glasses and ceramics, metals and alloys, and acceleration measurements. Life sciences included experiments on human health, cell separation and biology, developmental biology, animal and human physiology and behavior, space radiation, and biological rhythms. Test subjects included the crew, Japanese koi fish (carp), cultured animal and plant cells, chicken embryos, fruit flies, fungi and plant seeds, and frogs and frog eggs. Featured together in the Science Operation Area (SOA) are payload specialists' first Materials Processing Test during NASA/NASDA joint ground activities at the Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at Marshall Space Flight Center (MSFC).

Performance of a 260 Hz pulse tube cooler with metal fiber as the regenerator material

NASA Astrophysics Data System (ADS)

Wang, Xiaotao; Zhang, Shuang; Yu, Guoyao; Dai, Wei; Luo, Ercang

2014-01-01

Pulse tube coolers operating at higher frequency lead to a high energy density and result in a more compact system. This paper describes the performance of a 300 Hz pulse tube cooler driven by a linear compressor. Such high frequency operation leads to decreased thermal penetration, which requires a smaller hydraulic diameter and smaller wire diameter in the regenerator. In our previous experiments, the stainless steel mesh with a mesh number of 635 was used as the regenerator material, and a no-load temperature of 63 K was obtained. Both the numerical and experimental results indicate this material causes a large loss in the regenerator. A stainless steel fiber regenerator is introduced and studied in this article. Because this fiber has a wide range of wire diameter and porosity, such material might be more suitable for higher frequency pulse tube coolers. With the fiber as the regenerator material and after a series of optimizations, a no-load temperature of 45 K is acquired in the experiment. Influences of various parameters such as frequency and inertance tube length have been investigated experimentally.

PAMAM dendrimers and graphene: Materials for removing aromatic contaminants from water

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeFever, Ryan S.; Geitner, Nicholas K.; Bhattacharya, Priyanka

2015-04-07

We present results from experiments and atomistic molecular dynamics simulations on the association of naphthalene with polyamidoamine (PAMAM) dendrimers and graphene oxide (GrO). Specifically, we investigate 3rd-6th generation (G3-G6) PAMAM dendrimers and GrO with different levels of oxidation. The work is motivated by the potential applications of these materials in removing polycyclic aromatic hydrocarbon contaminants from water. Our experimental results indicate that graphene oxide outperforms dendrimers in removing naphthalene from water. Molecular dynamics simulations suggest that the prominent factors driving naphthalene association to these seemingly disparate materials are similar. Interestingly, we find that cooperative interactions between the naphthalene molecules playmore » a significant role in enhancing their association to the dendrimers and graphene oxide. Our findings highlight that while selection of appropriate materials is important, the interactions between the contaminants themselves can also be important in governing the effectiveness of a given material. The combined use of experiments and molecular dynamics simulations allows us to comment on the possible factors resulting in better performance of graphene oxide in removing naphthalene from water.« less

Machinability Study on Milling Kenaf Fiber Reinforced Plastic Composite Materials using Design of Experiments

NASA Astrophysics Data System (ADS)

Azmi, H.; Haron, C. H. C.; Ghani, J. A.; Suhaily, M.; Yuzairi, A. R.

2018-04-01

The surface roughness (Ra) and delamination factor (Fd) of a milled kenaf reinforced plastic composite materials are depending on the milling parameters (spindle speed, feed rate and depth of cut). Therefore, a study was carried out to investigate the relationship between the milling parameters and their effects on a kenaf reinforced plastic composite materials. The composite panels were fabricated using vacuum assisted resin transfer moulding (VARTM) method. A full factorial design of experiments was use as an initial step to screen the significance of the parameters on the defects using Analysis of Variance (ANOVA). If the curvature of the collected data shows significant, Response Surface Methodology (RSM) is then applied for obtaining a quadratic modelling equation that has more reliable in expressing the optimization. Thus, the objective of this research is obtaining an optimum setting of milling parameters and modelling equations to minimize the surface roughness (Ra) and delamination factor (Fd) of milled kenaf reinforced plastic composite materials. The spindle speed and feed rate contributed the most in affecting the surface roughness and the delamination factor of the kenaf composite materials.

Bubbles Responding to Ultrasound Pressure

NASA Technical Reports Server (NTRS)

2003-01-01

The Bubble and Drop Nonlinear Dynamics (BDND) experiment was designed to improve understanding of how the shape and behavior of bubbles respond to ultrasound pressure. By understanding this behavior, it may be possible to counteract complications bubbles cause during materials processing on the ground. This 12-second sequence came from video downlinked from STS-94, July 5 1997, MET:3/19:15 (approximate). The BDND guest investigator was Gary Leal of the University of California, Santa Barbara. The experiment was part of the space research investigations conducted during the Microgravity Science Laboratory-1R mission (STS-94, July 1-17 1997). Advanced fluid dynamics experiments will be a part of investigations plarned for the International Space Station. (435KB, 13-second MPEG, screen 160 x 120 pixels; downlinked video, higher quality not available) A still JPG composite of this movie is available at http://mix.msfc.nasa.gov/ABSTRACTS/MSFC-0300162.html.

Spacelab J: Microgravity and life sciences

NASA Technical Reports Server (NTRS)

1992-01-01

Spacelab J is a joint venture between NASA and the National Space Development Agency of Japan (NASDA). Using a Spacelab pressurized long module, 43 experiments will be performed in the areas of microgravity and life sciences. These experiments benefit from the microgravity environment available on an orbiting Shuttle. Removed from the effects of gravity, scientists will seek to observe processes and phenomena impossible to study on Earth, to develop new and more uniform mixtures, to study the effects of microgravity and the space environment on living organisms, and to explore the suitability of microgravity for certain types of research. Mission planning and an overview of the experiments to be performed are presented. Orbital research appears to hold many advantages for microgravity science investigations, which on this mission include electronic materials, metals and alloys, glasses and ceramics, fluid dynamics and transport phenomena, and biotechnology. Gravity-induced effects are eliminated in microgravity. This allows the investigations on Spacelab J to help scientists develop a better understanding of how these gravity-induced phenomena affect both processing and products on Earth and to observe subtle phenomena that are masked in gravity. The data and samples from these investigations will not only allow scientists to better understand the materials but also will lead to improvements in the methods used in future experiments. Life sciences research will collect data on human adaptation to the microgravity environment, investigate ways of assisting astronauts to readapt to normal gravity, explore the effects of microgravity and radiation on living organisms, and gather data on the fertilization and development of organisms in the absence of gravity. This research will improve crew comfort and safety on future missions while helping scientists to further understand the human body.

Vaccum Gas Tungsten Arc Welding, phase 1

NASA Astrophysics Data System (ADS)

Weeks, J. L.; Krotz, P. D.; Todd, D. T.; Liaw, Y. K.

1995-03-01

This two year program will investigate Vacuum Gas Tungsten Arc Welding (VGTAW) as a method to modify or improve the weldability of normally difficult-to-weld materials. VGTAW appears to offer a significant improvement in weldability because of the clean environment and lower heat input needed. The overall objective of the program is to develop the VGTAW technology and implement it into a manufacturing environment that will result in lower cost, better quality and higher reliability aerospace components for the space shuttle and other NASA space systems. Phase 1 of this program was aimed at demonstrating the process's ability to weld normally difficult-to-weld materials. Phase 2 will focus on further evaluation, a hardware demonstration and a plan to implement VGTAW technology into a manufacturing environment. During Phase 1, the following tasks were performed: (1) Task 11000 Facility Modification - an existing vacuum chamber was modified and adapted to a GTAW power supply; (2) Task 12000 Materials Selection - four difficult-to-weld materials typically used in the construction of aerospace hardware were chosen for study; (3) Task 13000 VGTAW Experiments - welding experiments were conducted under vacuum using the hollow tungsten electrode and evaluation. As a result of this effort, two materials, NARloy Z and Incoloy 903, were downselected for further characterization in Phase 2; and (4) Task 13100 Aluminum-Lithium Weld Studies - this task was added to the original work statement to investigate the effects of vacuum welding and weld pool vibration on aluminum-lithium alloys.

Vaccum Gas Tungsten Arc Welding, phase 1

NASA Technical Reports Server (NTRS)

Weeks, J. L.; Krotz, P. D.; Todd, D. T.; Liaw, Y. K.

1995-01-01

This two year program will investigate Vacuum Gas Tungsten Arc Welding (VGTAW) as a method to modify or improve the weldability of normally difficult-to-weld materials. VGTAW appears to offer a significant improvement in weldability because of the clean environment and lower heat input needed. The overall objective of the program is to develop the VGTAW technology and implement it into a manufacturing environment that will result in lower cost, better quality and higher reliability aerospace components for the space shuttle and other NASA space systems. Phase 1 of this program was aimed at demonstrating the process's ability to weld normally difficult-to-weld materials. Phase 2 will focus on further evaluation, a hardware demonstration and a plan to implement VGTAW technology into a manufacturing environment. During Phase 1, the following tasks were performed: (1) Task 11000 Facility Modification - an existing vacuum chamber was modified and adapted to a GTAW power supply; (2) Task 12000 Materials Selection - four difficult-to-weld materials typically used in the construction of aerospace hardware were chosen for study; (3) Task 13000 VGTAW Experiments - welding experiments were conducted under vacuum using the hollow tungsten electrode and evaluation. As a result of this effort, two materials, NARloy Z and Incoloy 903, were downselected for further characterization in Phase 2; and (4) Task 13100 Aluminum-Lithium Weld Studies - this task was added to the original work statement to investigate the effects of vacuum welding and weld pool vibration on aluminum-lithium alloys.

Spacelab

NASA Image and Video Library

1992-09-12

The group of Japanese researchers of the Spacelab-J (SL-J) were thumbs-up in the Payload Operations Control Center (POCC) at the Marshall Space Flight Center after the successful launch of Space Shuttle Orbiter Endeavour that carried their experiments. The SL-J was a joint mission of NASA and the National Space Development Agency of Japan (NASDA) utilizing a marned Spacelab module. The mission conducted microgravity investigations in materials and life sciences. Materials science investigations covered such fields as biotechnology, electronic materials, fluid dynamics and transport phenomena, glasses and ceramics, metals and alloys, and acceleration measurements. Life sciences included experiments on human health, cell separation and biology, developmental biology, animal and human physiology and behavior, space radiation, and biological rhythms. Test subjects included the crew, Japanese koi fish (carp), cultured animal and plant cells, chicken embryos, fruit flies, fungi and plant seeds, frogs, and frog eggs. The POCC was the air/ground communications channel between the astronauts and ground control teams during the Spacelab missions. The Spacelab science operations were a cooperative effort between the science astronaut crew in orbit and their colleagues in the POCC. Spacelab-J was launched aboard the Space Shuttle Orbiter Endeavour on September 12, 1992.

Activities During Spacelab-J Mission at Payload Operations and Control Center

NASA Technical Reports Server (NTRS)

1992-01-01

The group of Japanese researchers of the Spacelab-J (SL-J) were thumbs-up in the Payload Operations Control Center (POCC) at the Marshall Space Flight Center after the successful launch of Space Shuttle Orbiter Endeavour that carried their experiments. The SL-J was a joint mission of NASA and the National Space Development Agency of Japan (NASDA) utilizing a marned Spacelab module. The mission conducted microgravity investigations in materials and life sciences. Materials science investigations covered such fields as biotechnology, electronic materials, fluid dynamics and transport phenomena, glasses and ceramics, metals and alloys, and acceleration measurements. Life sciences included experiments on human health, cell separation and biology, developmental biology, animal and human physiology and behavior, space radiation, and biological rhythms. Test subjects included the crew, Japanese koi fish (carp), cultured animal and plant cells, chicken embryos, fruit flies, fungi and plant seeds, frogs, and frog eggs. The POCC was the air/ground communications channel between the astronauts and ground control teams during the Spacelab missions. The Spacelab science operations were a cooperative effort between the science astronaut crew in orbit and their colleagues in the POCC. Spacelab-J was launched aboard the Space Shuttle Orbiter Endeavour on September 12, 1992.

Characterization of Liquid Lithium Wetting and Thermoelectric Properties for Nuclear Fusion Applications

NASA Astrophysics Data System (ADS)

Fiflis, Peter; Xu, Wenyu; Christenson, Michael; Andruczyk, Daniel; Curreli, Davide; Ruzic, David

2013-10-01

Critical to the implementation of flowing liquid lithium plasma facing components is understanding the interactions of liquid lithium with various surfaces. Presented here are experiments investigating the material compatibility, wetting characteristics, and relative thermopower of liquid lithium with a variety of potential substrate candidates for the LiMIT concept. Wetting experiments with lithium used the contact angle as a metric. Among those materials investigated are 316 SS, Mo, Ta, and W. The contact angle, as well as its dependence on temperature was measured. For example, at 200 C, tungsten registers a contact angle of 130°, whereas above its wetting temperature of 350 C, the contact angle is less than 80°. Several methods were found to decrease the critical wetting temperature of various materials and are presented here. The thermopower of W, Mo, Ta, Li, Ga, Wood's metal and Sn has been measured relative to stainless steel, and the Seebeck coefficient of has then been calculated. For molybdenum the Seebeck coefficient has a linear rise with temperature from SMo = 3.9 μVK-1 at 30 °C to 7.5 μVK-1 at 275 °C. On Assignment at PPPL

The Influence of Reduced Gravity on the Crystal Growth of Electronic Materials

NASA Technical Reports Server (NTRS)

Su, Ching-Hua; Gillies, D. C.; Szofran, F. R.; Watring, D. A.; Lehoczky, S. L.

1996-01-01

The imperfections in the grown crystals of electronic materials, such as compositional nonuniformity, dopant segregation and crystalline structural defects, are detrimental to the performance of the opto-electronic devices. Some of these imperfections can be attributed to effects caused by Earth gravity during crystal growth process and four areas have been identified as the uniqueness of material processing in reduced gravity environment. The significant results of early flight experiments, i.e. prior to space shuttle era, are briefly reviewed followed by an elaborated review on the recent flight experiments conducted on shuttle missions. The results are presented for two major growth methods of electronic materials: melt and vapor growth. The use of an applied magnetic field in the melt growth of electrically conductive melts on Earth to simulate the conditions of reduced gravity has been investigated and it is believed that the superimposed effect of moderate magnetic fields and the reduced gravity environment of space can result in reduction of convective intensities to the extent unreachable by the exclusive use of magnet on Earth or space processing. In the Discussions section each of the significant results of the flight experiments is attributed to one of the four effects of reduced gravity and the unresolved problems on the measured mass fluxes in some of the vapor transport flight experiments are discussed.

The Viking biological investigation - Preliminary results

NASA Technical Reports Server (NTRS)

Klein, H. P.; Oyama, V. I.; Berdahl, B. J.; Horowitz, N. H.; Hobby, G. L.; Levin, G. V.; Straat, P. A.; Lederberg, J.; Rich, A.; Hubbard, J. S.

1976-01-01

A preliminary progress report is presented for the Viking biological investigation through its first month. The carbon assimilation, gas exchange, and labeled release experiments are described in detail, and the chronology of the experiments is outlined. For the first experiment, it is found that a small amount of gas was converted into organic material in one sample and that heat treatment of a duplicate sample prevented such conversion. In the second experiment, a substantial amount of O2 was detected along with significant increases in CO2 and small changes in N2. In the third experiment, a significant amount of radioactive gas was evolved from one sample, but not from a duplicate heat-treated sample. Possible biological and nonbiological interpretations are considered for these results. It is concluded that while the experiments provide clear evidence for the occurrence of chemical reactions and while the results do not violate any prima facie criteria for biological processes, a definitive answer cannot yet be given to the question of whether life exists on Mars.

Ontological and Epistemological Issues Regarding Climate Models and Computer Experiments

NASA Astrophysics Data System (ADS)

Vezer, M. A.

2010-12-01

Recent philosophical discussions (Parker 2009; Frigg and Reiss 2009; Winsberg, 2009; Morgon 2002, 2003, 2005; Gula 2002) about the ontology of computer simulation experiments and the epistemology of inferences drawn from them are of particular relevance to climate science as computer modeling and analysis are instrumental in understanding climatic systems. How do computer simulation experiments compare with traditional experiments? Is there an ontological difference between these two methods of inquiry? Are there epistemological considerations that result in one type of inference being more reliable than the other? What are the implications of these questions with respect to climate studies that rely on computer simulation analysis? In this paper, I examine these philosophical questions within the context of climate science, instantiating concerns in the philosophical literature with examples found in analysis of global climate change. I concentrate on Wendy Parker’s (2009) account of computer simulation studies, which offers a treatment of these and other questions relevant to investigations of climate change involving such modelling. Two theses at the center of Parker’s account will be the focus of this paper. The first is that computer simulation experiments ought to be regarded as straightforward material experiments; which is to say, there is no significant ontological difference between computer and traditional experimentation. Parker’s second thesis is that some of the emphasis on the epistemological importance of materiality has been misplaced. I examine both of these claims. First, I inquire as to whether viewing computer and traditional experiments as ontologically similar in the way she does implies that there is no proper distinction between abstract experiments (such as ‘thought experiments’ as well as computer experiments) and traditional ‘concrete’ ones. Second, I examine the notion of materiality (i.e., the material commonality between object and target systems) and some arguments for the claim that materiality entails some inferential advantage to traditional experimentation. I maintain that Parker’s account of the ontology of computer simulations has some interesting though potentially problematic implications regarding conventional distinctions between abstract and concrete methods of inquiry. With respect to her account of materiality, I outline and defend an alternative account, posited by Mary Morgan (2002, 2003, 2005), which holds that ontological similarity between target and object systems confers some epistemological advantage to traditional forms of experimental inquiry.

High-Z material erosion and its control in DIII-D carbon divertor

DOE PAGES

Ding, Rui; Rudakov, Dimitry L.; Stangeby, Peter C.; ...

2017-03-16

It is expected that high-Z materials will be used as plasma-facing components (PFCs) in future fusion devices, making the erosion of high-Z material a key issue for high-power, long pulse operation. High-Z material erosion and redeposition have been studied using tungsten and molybdenum coated samples exposed in well-diagnosed DIII-D divertor plasma discharges. By coupling dedicated experiments and modelling using the 3D Monte Carlo code ERO, the roles of sheath potential and background carbon impurities in determining high-Z material erosion are identified. Different methods suggested by modelling have been investigated to control high-Z material erosion in DIII-D experiments. The erosion ofmore » Mo and W are found to be strongly suppressed by local injection of methane and deuterium gases. The 13C deposition resulting from local 13CH 4 injection also provides information on radial transport due to E×B drifts and cross field diffusion. Finally, D 2 gas puffing is found to cause 2 local plasma perturbation, suppressing W erosion because of the lower effective sputtering yield of W at lower plasma temperature and for higher carbon concentration in the mixed surface layer.« less

Pure Material Vapor Source by Induction Heating Evaporator for an Electron Cyclotron Resonance Ion Source

NASA Astrophysics Data System (ADS)

Matsui, Y.; Watanabe, T.; Satani, T.; Muramatsu, M.; Tanaka, K.; Kitagawa, A.; Yoshida, Y.; Sato, F.; Kato, Y.; Iida, T.

2008-11-01

Multiply charged iron ions are produced from solid pure material in an electron cyclotron resonance (ECR) ion source. We develop an evaporator by using induction heating with the induction coil which is made from bare molybdenum wire and surrounding the pure iron rod. We optimize the shape of induction heating coil and operation of rf power supply. We conduct experiment to investigate reproducibility and stability in the operation and heating efficiency. Induction heating evaporator produces pure material vapor, because materials directly heated by eddy currents have non-contact with insulated materials which are impurity gas sources. The power and the frequency of the induction currents range from 100 to 900 W and from 48 to 23 kHz, respectively. The working pressure is about 10-4 to 10-3 Pa. We measure temperature of iron rod and film deposition rate by depositing iron vapor to crystal oscillator. We confirm stability and reproducibility of evaporator enough to conduct experiment in ECR ion source. We can obtain required temperature of iron under maximum power of power supply. We are aiming the evaporator higher melting point material than iron.

Study for material analogs of FeSb2: Material design for thermoelectric materials

NASA Astrophysics Data System (ADS)

Kang, Chang-Jong; Kotliar, Gabriel

2018-03-01

Using the ab initio evolutionary algorithm (implemented in uspex) and electronic structure calculations we investigate the properties of a new thermoelectric material FeSbAs, which is a material analog of the enigmatic thermoelectric FeSb2. We utilize the density functional theory and the Gutzwiller method to check the energetics. We find that FeSbAs can be made thermodynamically stable above ˜30 GPa. We investigate the electronic structure and thermoelectric properties of FeSbAs based on the density functional theory and compare with those of FeSb2. Above 50 K, FeSbAs has higher Seebeck coefficients than FeSb2. Upon doping, the figure of merit becomes larger for FeSbAs than for FeSb2. Another material analog FeSbP, was also investigated, and found thermodynamically unstable even at very high pressure. Regarding FeSb2 as a member of a family of compounds (FeSb2, FeSbAs, and FeSbP) we elucidate what are the chemical handles that control the gaps in this series. We also investigate solubility (As or P for Sb in FeSb2) we found As to be more soluble. Finally, we study a two-band model for thermoelectric properties and find that the temperature dependent chemical potential and the presence of the ionized impurities are important to explain the extremum in the Seebeck coefficient exhibited in experiments for FeSb2.

Study for material analogs of FeSb 2 : Material design for thermoelectric materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, Chang-Jong; Kotliar, Gabriel

Using the ab initio evolutionary algorithm (implemented in uspex) and electronic structure calculations we investigate the properties of a new thermoelectric material FeSbAs, which is a material analog of the enigmatic thermoelectric FeSb 2. We utilize the density functional theory and the Gutzwiller method to check the energetics. We find that FeSbAs can be made thermodynamically stable above ~ 30 GPa. We investigate the electronic structure and thermoelectric properties of FeSbAs based on the density functional theory and compare with those of FeSb 2. Above 50 K, FeSbAs has higher Seebeck coefficients than FeSb 2. Upon doping, the figure ofmore » merit becomes larger for FeSbAs than for FeSb 2. Another material analog FeSbP, was also investigated, and found thermodynamically unstable even at very high pressure. Regarding FeSb 2 as a member of a family of compounds (FeSb 2, FeSbAs, and FeSbP) we elucidate what are the chemical handles that control the gaps in this series. Here, we also investigate solubility (As or P for Sb in FeSb 2) we found As to be more soluble. Finally, we study a two-band model for thermoelectric properties and find that the temperature dependent chemical potential and the presence of the ionized impurities are important to explain the extremum in the Seebeck coefficient exhibited in experiments for FeSb 2.« less

Study for material analogs of FeSb 2 : Material design for thermoelectric materials

DOE PAGES

Kang, Chang-Jong; Kotliar, Gabriel

2018-03-16

Using the ab initio evolutionary algorithm (implemented in uspex) and electronic structure calculations we investigate the properties of a new thermoelectric material FeSbAs, which is a material analog of the enigmatic thermoelectric FeSb 2. We utilize the density functional theory and the Gutzwiller method to check the energetics. We find that FeSbAs can be made thermodynamically stable above ~ 30 GPa. We investigate the electronic structure and thermoelectric properties of FeSbAs based on the density functional theory and compare with those of FeSb 2. Above 50 K, FeSbAs has higher Seebeck coefficients than FeSb 2. Upon doping, the figure ofmore » merit becomes larger for FeSbAs than for FeSb 2. Another material analog FeSbP, was also investigated, and found thermodynamically unstable even at very high pressure. Regarding FeSb 2 as a member of a family of compounds (FeSb 2, FeSbAs, and FeSbP) we elucidate what are the chemical handles that control the gaps in this series. Here, we also investigate solubility (As or P for Sb in FeSb 2) we found As to be more soluble. Finally, we study a two-band model for thermoelectric properties and find that the temperature dependent chemical potential and the presence of the ionized impurities are important to explain the extremum in the Seebeck coefficient exhibited in experiments for FeSb 2.« less

Investigating lava-substrate interactions through flow experiments with syrup, wax, and molten basalt

NASA Astrophysics Data System (ADS)

Rumpf, M. E.; Lev, E.

2015-12-01

Among the many factors influencing the complex process of lava flow emplacement, the interaction with the substrate onto which flow is emplaced plays a central role. Lava flows are rarely emplaced onto smooth or regular surfaces. For example, at Kīlauea Volcano, Hawai'i, lava flows regularly flow over solid rock, vegetation, basaltic or silica sand, and man-made materials, including asphalt and concrete. In situ studies of lava-substrate interactions are inherently difficult, and often dangerous, to carry-out, requiring the design of controllable laboratory experiments. We investigate the effects of substrate grain size, cohesion, and roughness on flow mobility and morphology through a series of flow experiments using analog materials and molten basalt. We have developed a series of experiments that allow for adjustable substrate parameters and analyze their effects on lava flow emplacement. The first set of experiments are performed at the Fluids Mechanics Laboratory at the Lamont-Doherty Earth Observatory and focus on two analog materials: polyethylene glycol (PEG), a commercially available wax, and corn syrup. The fluids were each extruded onto a series of scaled substrate beds to replicate the emplacement of lava in a natural environment. Preliminary experiments demonstrated that irregular topography, particularly topography with a height amplitude similar to that of the flow itself, can affect flow morphology, width, and velocity by acting as local barriers or culverts to the fluid. This is expected from observations of fluid flow in natural environments. A follow-up set of experiments will be conducted in Fall 2015 at the Syracuse University (SU) Lava Project Lab. In this set, we will pour molten basalt directly onto a series of substrates representing natural environments found on the Earth and other rocky bodies in the Solar System. These experiments will allow for analysis of the effects of basaltic composition and high temperatures on lava-substrate heat transfer and mechanical interactions. Results will be used to improve current lava flow prediction models as well as increase our understanding of the evolution of volcanic regions on the Earth and other planets.

MGBX - PS Crouch with experiment module

NASA Image and Video Library

2016-08-12

STS083-346-024 (4-8 April 1997) --- Payload specialist Roger K. Crouch performs the activation for the Mid Deck Glove Box (MGBX). Made to accommodate a variety of hardware and materials testing, the facility offers physical isolation and a negative air pressure environment so that items that are not suitable for handling in the open Spacelab can be protected. One experiment that was performed on STS-83 is the Internal Flows in a Free Drop (IFFD), an experiment that investigates rotation and position control of drops by varying acoustic pressures.

Design, synthesis, and characterization of lightly sulfonated multigraft acrylate-based copolymer superelastomers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Misichronis, Konstantinos; Wang, Weiyu; Cheng, Shiwang

2018-01-29

Multigraft copolymer superelastomers consisting of a poly(n-butyl acrylate) backbone and polystyrene side chains were synthesized and the viscoelastic properties of the non-sulfonated and sulfonated final materials were investigated using extensional rheology (SER3). The non-linear viscoelastic experiments revealed significantly increased true stresses (up to 10 times higher) after sulfonating only 2–3% of the copolymer while the materials maintained high elongation (<700%). The linear viscoelastic experiments showed that the storage and loss modulus are increased by sulfonation and that the copolymers can be readily tuned and further improved by increasing the number of branching points and the molecular weight of the backbone.more » Here, in this way, we show that by tuning not only the molecular characteristics of the multigraft copolymers but also their architecture and chemical interaction, we can acquire thermoplastic superelastomer materials with desired viscoelastic properties.« less

Shear Tests and Calculation of Shear Resistance with the PC Program RFEM from Thin Partition Walls of Brick in Old Buildings

NASA Astrophysics Data System (ADS)

Korjenic, Sinan; Nowak, Bernhard; Löffler, Philipp; Vašková, Anna

2015-11-01

This paper is about the shear capacity of partition walls in old buildings based on shear tests which were carried out under real conditions in an existing building. There were experiments conducted on different floors and in each case, the maximum recordable horizontal force and the horizontal displacement of the respective mortar were measured. At the same time material studies and material investigations were carried out in the laboratory. The material parameters were used for the calculation of the precise shear capacity of each joint. In the shear tests, the maximum displacement of a mortar joint was determined at a maximum of two to four millimetres. Furthermore, no direct linear relationship between the theoretical load (wall above it) and the shear stress occurred could be detected in the analysis of the experiment, as it was previously assumed.

Spacelab

NASA Image and Video Library

1992-09-01

Japanese astronaut, Mamoru Mohri, talks to Japanese students from the aft flight deck of the Space Shuttle Orbiter Endeavour during the Spacelab-J (SL-J) mission. The SL-J mission was a joint venture between NASA and the National Space Development Agency of Japan (NASDA) utilizing a marned Spacelab module. The mission conducted 24 materials science and 20 life science experiments, of which 35 were sponsored by NASDA, 7 by NASA, and two collaborative efforts. Materials science investigations covered such fields as biotechnology, electronic materials, fluid dynamics and transport phenomena, glasses and ceramics, metals and alloys, and acceleration measurements. Life sciences included experiments on human health, cell separation and biology, developmental biology, animal and human physiology and behavior, space radiation, and biological rhythms. Test subjects included the crew, Japanese koi fish (carp), cultured animal and plant cells, chicken embryos, fruit flies, fungi and plant seeds, and frogs and frog eggs. Spacelab-J was launched aboard the Space Shuttle Orbiter Endeavour on September 12, 1992.

Around Marshall

NASA Image and Video Library

1992-09-12

The science laboratory, Spacelab-J (SL-J), flown aboard the STS-47 flight was a joint venture between NASA and the National Space Development Agency of Japan (NASDA) utilizing a manned Spacelab module. The mission conducted 24 materials science and 20 life science experiments, of which 35 were sponsored by NASDA, 7 by NASA, and two collaborative efforts. Materials science investigations covered such fields as biotechnology, electronic materials, fluid dynamics and transport phenomena, glasses and ceramics, metals and alloys, and acceleration measurements. Life sciences included experiments on human health, cell separation and biology, developmental biology, animal and human physiology and behavior, space radiation, and biological rhythms. Test subjects included the crew, Japanese koi fish (carp), cultured animal and plant cells, chicken embryos, fruit flies, fungi and plant seeds, and frogs and frog eggs. Pictured in the Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) of Marshall Space Flight Center (MSFC) are NASDA alternate payload specialists Dr. Doi and Dr. Mukai.

Elements of Scenario-Based Learning on Suicidal Patient Care Using Real-Time Video.

PubMed

Lu, Chuehfen; Lee, Hueying; Hsu, Shuhui; Shu, Inmei

2016-01-01

This study aims understanding of students' learning experiences when receiving scenario-based learning combined with real-time video. Videos that recorded student nurses intervention with a suicidal standardized patient (SP) were replayed immediately as teaching materials. Videos clips and field notes from ten classes were analysed. Investigators and method triangulation were used to boost the robustness of the study. Three key elements, emotional involvement, concretizing of the teaching material and substitute learning were identified. Emotions were evoked among the SP, the student performer and the students who were observing, thus facilitating a learning effect. Concretizing of the teaching material refers to students were able to focus on the discussions using visual and verbal information. Substitute learning occurred when the students watching the videos, both the strengths and weaknesses represented were similar to those that would be likely to occur. These key elements explicate their learning experience and suggested a strategic teaching method.

A Study on Phase Changes of Heterogeneous Composite Materials

NASA Astrophysics Data System (ADS)

Hirasawa, Yoshio; Saito, Akio; Takegoshi, Eisyun

In this study, a phase change process in heterogeneous composite materials which consist of water and coiled copper wires as conductive solid is investigated by four kinds of typical calculation models : 1) model-1 in which the effective thermal conductivity of the composite material is used, 2) model-2 in which a fin metal acts for many conductive solids, 3) model-3 in which the effective thermal conductivities between nodes are estimated and three-dimensional calculation is performed, 4) model-4 proposed by authors in the previous paper in which effective thermal conductivity is not needed. Consequently, model-1 showed the phase change rate considerably lower than the experimental results. Model-2 gave the larger amount of the phase change rate. Model-3 agreed well with the experiment in the case of small coil diameter and relatively large Vd. Model-4 showed a very well agreement with the experiment in the range of this study.

Overview of NASA's Microgravity Materials Research Program

NASA Technical Reports Server (NTRS)

Downey, James Patton; Grugel, Richard

2012-01-01

The NASA microgravity materials program is dedicated to conducting microgravity experiments and related modeling efforts that will help us understand the processes associated with the formation of materials. This knowledge will help improve ground based industrial production of such materials. The currently funded investigations include research on the distribution of dopants and formation of defects in semiconductors, transitions between columnar and dendritic grain morphology, coarsening of phase boundaries, competition between thermally and kinetically favored phases, and the formation of glassy vs. crystalline material. NASA microgravity materials science investigators are selected for funding either through a proposal in response to a NASA Research Announcement or by participation in a team proposing to a foreign agency research announcement. In the latter case, a US investigator participating in a successful proposal to a foreign agency can then apply to NASA for funding of an unsolicited proposal. The program relies on cooperation with other aerospace partners from around the world. The ISS facilities used for these investigations are provided primarily by partnering with foreign agencies and in most cases the US investigators are working as a part of a larger team studying a specific area of materials science. The following facilities are to be utilized for the initial investigations. The ESA provided Low Gradient Facility and the Solidification and Quench Inserts to the Materials Research Rack/Materials Science Laboratory are to be used primarily for creating bulk samples that are directionally solidified or quenched from a high temperature melt. The CNES provided DECLIC facility is used to observe morphological development in transparent materials. The ESA provided Electro-Magnetic Levitator (EML) is designed to levitate, melt and then cool samples in order to study nucleation behavior. The facility provides conditions in which nucleation of the solid is not triggered from the wall and in which fluid flows in the sample can be controlled and manipulated. These conditions allow scientists ideal conditions for understanding the relative amounts and distribution of different phases that form in the solid. Finally, the Coarsening of Solid Liquid Melts hardware allows quenching of low temperature samples in the Microgravity Science Glovebox.

Simulation of shear plugging through thin plates using the GRIM Eulerian hydrocode

NASA Astrophysics Data System (ADS)

Church, P.; Cornish, R.; Cullis, I.; Lynch, N.

2000-03-01

Ballistic experiments have been performed using aluminum spheres against 10-mm rolled homogenous armour (RHA), MARS270, MARS300, and titanium alloy plates to investigate the influence of the plugging mechanism on material properties. The experiments have measured the threshold for plug mass and velocity as well as the recovered aluminum sphere mass over a range of velocities. Some of the experiments have been simulated using the in-house second generation Eulerian hydrocode GRIM. The calculations feature advanced material algorithms derived from interrupted tensile testing techniques and a triaxial failure model derived from notched tensile tests over a range of strain rates and temperatures. The effect of mesh resolution on the results has been investigated and understood. The simulation results illustrate the importance of the constitutive model in the shear localization process and the subsequent plugging phenomena. The stress triaxiality is seen as the dominant feature in controlling the onset and subsequent propagation of the crack leading to the shear plug. The simulations have demonstrated that accurate numerics coupled with accurate constitutive and fracture algorithms can successfully reproduce the observed experimental features. However, extrapolation of the fracture data leads to the simulations overpredicting the plug damage. The reasons for this are discussed.

Feasibility study: Atmospheric general circulation experiment, volume 1

NASA Technical Reports Server (NTRS)

Homsey, R. J. (Editor)

1981-01-01

The atmospheric general circulation experiment (AGCE) uses a rotating fluid flow cell assembly. The key technical areas affecting the feasibility of the design and operation of the AGCE are investigated. The areas investigated include materials for the flow cell assembly, thermal design, high voltage power supply design, effective retrieval and handling of experiment data and apparatus configuration. Several materials, DMSO and m-tolunitrile, were selected as candidate fluids for the flow cell principally for their high dielectric constant which permits the high voltage power supply design to be held to 15 kV and still simulate terrestrial gravity. Achievement of a low dissipation factor in the fluid to minimize internal heating from the applied electrical field depends strongly on purification and handling procedures. The use of sapphire as the outer hemisphere for the flow cell provides excellent viewing conditions without a significant impact on attaining the desired thermal gradients. Birefringent effects from sapphire can be held to acceptably low limits. Visualization of flow fluid is achieved through the motion of a dot matrix formed by photochromic dyes. Two dyes found compatible with the candidate fluids are spiropyran and triarylmethane. The observation of the dot motion is accomplished using a flying spot scanner.

ACE-1 experiment

NASA Image and Video Library

2013-06-24

In the International Space Stations Destiny laboratory,NASA astronaut Karen Nyberg,Expedition 36 flight engineer,speaks into a microphone while conducting a session with the Advanced Colloids Experiment (ACE)-1 sample preparation at the Light Microscopy Module (LMM) in the Fluids Integrated Rack / Fluids Combustion Facility (FIR/FCF). ACE-1 is a series of microscopic imaging investigations that uses the microgravity environment to examine flow characteristics and the evolution and ordering effects within a group of colloidal materials.

Radon and material radiopurity assessment for the NEXT double beta decay experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cebrián, S.; Dafni, T.; González-Díaz, D.

The ”Neutrino Experiment with a Xenon TPC” (NEXT), intended to investigate the neutrinoless double beta decay using a high-pressure xenon gas TPC filled with Xe enriched in {sup 136}Xe at the Canfranc Underground Laboratory in Spain, requires ultra-low background conditions demanding an exhaustive control of material radiopurity and environmental radon levels. An extensive material screening process is underway for several years based mainly on gamma-ray spectroscopy using ultra-low background germanium detectors in Canfranc but also on mass spectrometry techniques like GDMS and ICPMS. Components from shielding, pressure vessel, electroluminescence and high voltage elements and energy and tracking readout planes havemore » been analyzed, helping in the final design of the experiment and in the construction of the background model. The latest measurements carried out will be presented and the implication on NEXT of their results will be discussed. The commissioning of the NEW detector, as a first step towards NEXT, has started in Canfranc; in-situ measurements of airborne radon levels were taken there to optimize the system for radon mitigation and will be shown too.« less

Microgravity

NASA Image and Video Library

1998-01-25

A test cell for Mechanics of Granular Materials (MGM) experiment is shown approximately 20 and 60 minutes after the start of an experiment on STS-89. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditons that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: NASA/Marshall Space Flight Center (MSFC)

Electrochemical processing of solid waste

NASA Technical Reports Server (NTRS)

Bockris, J. OM.; Hitchens, G. D.; Kaba, L.

1988-01-01

The investigation into electrolysis as a means of waste treatment and recycling on manned space missions is described. The electrochemical reactions of an artificial fecal waste mixture was examined. Waste electrolysis experiments were performed in a single compartment reactor, on platinum electrodes, to determine conditions likely to maximize the efficiency of oxidation of fecal waste material to CO2. The maximum current efficiencies for artificial fecal waste electrolysis to CO2 was found to be around 50 percent in the test apparatus. Experiments involving fecal waste oxidation on platinum indicates that electrodes with a higher overvoltage for oxygen evolution such as lead dioxide will give a larger effective potential range for organic oxidation reactions. An electrochemical packed column reactor was constructed with lead dioxide as electrode material. Preliminary experiments were performed using a packed-bed reactor and continuous flow techniques showing this system may be effective in complete oxidation of fecal material. The addition of redox mediator Ce(3+)/Ce(4+) enhances the oxidation process of biomass components. Scientific literature relevant to biomass and fecal waste electrolysis were reviewed.

Verbal redundancy aids memory for filmed entertainment dialogue.

PubMed

Hinkin, Michael P; Harris, Richard J; Miranda, Andrew T

2014-01-01

Three studies investigated the effects of presentation modality and redundancy of verbal content on recognition memory for entertainment film dialogue. U.S. participants watched two brief movie clips and afterward answered multiple-choice questions about information from the dialogue. Experiment 1 compared recognition memory for spoken dialogue in the native language (English) with subtitles in English, French, or no subtitles. Experiment 2 compared memory for material in English subtitles with spoken dialogue in English, French, or no sound. Experiment 3 examined three control conditions with no spoken or captioned material in the native language. All participants watched the same video clips and answered the same questions. Performance was consistently good whenever English dialogue appeared in either the subtitles or sound, and best of all when it appeared in both, supporting the facilitation of verbal redundancy. Performance was also better when English was only in the subtitles than when it was only spoken. Unexpectedly, sound or subtitles in an unfamiliar language (French) modestly improved performance, as long as there was also a familiar channel. Results extend multimedia research on verbal redundancy for expository material to verbal information in entertainment media.

Investigation Into the Utilization of 3D Printing in Laser Cooling Experiments

NASA Astrophysics Data System (ADS)

Hazlett, Eric

With the advancement of 3D printing new opportunities are abound in many different fields, but with the balance between the precisions of atomic physics experiments and the material properties of current 3D printers the benefit of 3D printing technology needs to be investigated. We report on the progress of two investigations of 3D printing of benefit to atomic physics experiments: laser feedback module and the other being an optical chopper. The first investigation looks into creation of a 3D printed laser diode feedback module. This 3D printed module would allow for the quick realization of an external cavity diode laser that would have an adjustable cavity distance. We will report on the first tests of this system, by looking at Rb spectroscopy and mode-hop free tuning range as well as possibilities of using these lasers for MOT generation. We will also discuss our investigation into a 3D-printed optical chopper that utilizes an Arduino and a computer hard drive motor. By implementing an additional Arduino we create a low cost way to quickly measure laser beam waists

Investigation Into the Utilization of 3D Printing in Laser Cooling Experiments

NASA Astrophysics Data System (ADS)

Hazlett, Eric; Nelson, Brandon; de Leon, Sam Diaz; Shaw, Jonah

2016-05-01

With the advancement of 3D printing new opportunities are abound in many different fields, but with the balance between the precisions of atomic physics experiments and the material properties of current 3D printers the benefit of 3D printing technology needs to be investigated. We report on the progress of two investigations of 3D printing of benefit to atomic physics experiments: laser feedback module and the other being an optical chopper. The first investigation looks into creation of a 3D printed laser diode feedback module. This 3D printed module would allow for the quick realization of an external cavity diode laser that would have an adjustable cavity distance. We will report on the first tests of this system, by looking at Rb spectroscopy and mode-hop free tuning range as well as possibilities of using these lasers for MOT generation. We will also discuss our investigation into a 3D-printed optical chopper that utilizes an Arduino and a computer hard drive motor. By implementing an additional Arduino we create a low cost way to quickly measure laser beam waists.

Parts, Materials, and Processes Experience Summary. Volume 1; [Catalog of ALERT and Other Information on Basic Design, Reliability, Quality and Applications Programs

NASA Technical Reports Server (NTRS)

1973-01-01

The ALERT program, a system for communicating common problems with parts, materials, and processes, is condensed and catalogued. Expanded information on selected topics is provided by relating the problem area (failure) to the cause, the investigations and findings, the suggestions for avoidance (inspections, screening tests, proper part applications), and failure analysis procedures. The basic objective of ALERT is the avoidance of the recurrence of parts, materials, and processed problems, thus improving the reliability of equipment produced for and used by the government.

Can One Lab Make a Difference?

ERIC Educational Resources Information Center

Abbott, David S.; Saul, Jeffery M.; Parker, George W.; Beichner, Robert J.

2000-01-01

Investigates whether replacing a single traditional laboratory activity with a widely-used, non-microcomputer-based laboratory, research-based activity could produce improved conceptual understanding of a topic in electricity. Shows that a single instructional experience utilizing the research-based tutorial materials is superior to a traditional…

Real-Time Investigation of Solidification of Metal Matrix Composites

NASA Technical Reports Server (NTRS)

Kaukler, William; Sen, Subhayu

1999-01-01

Casting of metal matrix composites can develop imperfections either as non- uniform distributions of the reinforcement phases or as outright defects such as porosity. The solidification process itself initiates these problems. To identify or rectify the problems, one must be able to detect and to study how they form. Until, recently this was only possible by experiments that employed transparent metal model organic materials with glass beads to simulate the reinforcing phases. Recent results obtained from a Space Shuttle experiment (using transparent materials) will be used to illustrate the fundamental physics that dictates the final distribution of agglomerates in a casting. We have further extended this real time investigation to aluminum alloys using X-ray microscopy. A variety of interface-particle interactions will be discussed and how they alter the final properties of the composite. A demonstration of how a solid-liquid interface is distorted by nearby voids or particles, particle pushing or engulfment by the interface, formations of wormholes, Aggregation of particles, and particle-induced segregation of alloying elements will be presented.

Review on the EFDA programme on tungsten materials technology and science

NASA Astrophysics Data System (ADS)

Rieth, M.; Boutard, J. L.; Dudarev, S. L.; Ahlgren, T.; Antusch, S.; Baluc, N.; Barthe, M.-F.; Becquart, C. S.; Ciupinski, L.; Correia, J. B.; Domain, C.; Fikar, J.; Fortuna, E.; Fu, C.-C.; Gaganidze, E.; Galán, T. L.; García-Rosales, C.; Gludovatz, B.; Greuner, H.; Heinola, K.; Holstein, N.; Juslin, N.; Koch, F.; Krauss, W.; Kurzydlowski, K. J.; Linke, J.; Linsmeier, Ch.; Luzginova, N.; Maier, H.; Martínez, M. S.; Missiaen, J. M.; Muhammed, M.; Muñoz, A.; Muzyk, M.; Nordlund, K.; Nguyen-Manh, D.; Norajitra, P.; Opschoor, J.; Pintsuk, G.; Pippan, R.; Ritz, G.; Romaner, L.; Rupp, D.; Schäublin, R.; Schlosser, J.; Uytdenhouwen, I.; van der Laan, J. G.; Veleva, L.; Ventelon, L.; Wahlberg, S.; Willaime, F.; Wurster, S.; Yar, M. A.

2011-10-01

All the recent DEMO design studies for helium cooled divertors utilize tungsten materials and alloys, mainly due to their high temperature strength, good thermal conductivity, low erosion, and comparably low activation under neutron irradiation. The long-term objective of the EFDA fusion materials programme is to develop structural as well as armor materials in combination with the necessary production and fabrication technologies for future divertor concepts. The programmatic roadmap is structured into four engineering research lines which comprise fabrication process development, structural material development, armor material optimization, and irradiation performance testing, which are complemented by a fundamental research programme on "Materials Science and Modeling". This paper presents the current research status of the EFDA experimental and testing investigations, and gives a detailed overview of the latest results on fabrication, joining, high heat flux testing, plasticity, modeling, and validation experiments.

Investigations of Heat Transfer in Vacuum between Room Temperature and 80 K

NASA Astrophysics Data System (ADS)

Hooks, J.; Demko, J. A.; E Fesmire, J.; Matsumoto, T.

2017-12-01

The heat transfer between room temperature and 80 K is controlled using various insulating material combinations. The modes of heat transfer are well established to be conduction and thermal radiation when in a vacuum. Multi-Layer Insulation (MLI) in a vacuum has long been the best approach. Typically this layered system is applied to the cold surface. This paper investigates the application of MLI to both the cold and warm surface to see whether there is a significant difference. In addition if MLI is on the warm surface, the cold side of the MLI may be below the critical temperature of some high temperature superconducting (HTS) materials. It has been proposed that HTS materials can serve to block thermal radiation. An experiment is conducted to measure this effect. Boil-off calorimetry is the method of measuring the heat transfer.

Striated abrasions from a knife with non-serrated blade--identification of the instrument of crime on the basis of an experiment with material evidence.

PubMed

Kaliszan, Michał; Karnecki, Karol; Akçan, Ramazan; Jankowski, Zbigniew

2011-09-01

This paper presents an experiment with a knife seized as material evidence in a homicide case. The reason for the experiment was the necessity to determine whether the injuries of the deceased could have been inflicted with this instrument since in the course of the investigation doubt arose as to the origin of linear, parallel scratches around one of the wounds and on the abdominal integuments suggesting a serrated blade. The knife found near the crime scene had a smooth blade and small serrations only on the borderline between its blade and hilt. However, the performed experiment showed that if the knife is directed towards the integuments of the body in a special way, its serrations, even though not located on the blade itself, may leave such striated marks on the body, as those found during the autopsy, suggesting their origin from a serrated blade.

The Microstructural Evolution of Fatigue Cracks in FCC Metals

NASA Astrophysics Data System (ADS)

Gross, David William

The microstructural evolution during fatigue crack propagation was investigated in a variety of planar and wavy slip FCC metals. The planar materials included Haynes 230, Nitronic 40, and 316 stainless steel, and the wavy materials included pure nickel and pure copper. Three different sets of experiments were performed to fully characterize the microstructural evolution. The first, performed on Haynes 230, mapped the strain field ahead a crack tip using digital image correlation and electron backscatter diffraction techniques. Focused ion beam (FIB) lift-out techniques were then utilized to extract transmission electron microscopy (TEM) samples at specific distances from the crack tip. TEM investigations compared the measured strain to the microstructure. Overall, the strain measured via DIC and EBSD was only weakly correlated to the density of planar slip bands in the microstructure. The second set of experiments concerned the dislocation structure around crack tips. This set of experiments was performed on all the materials. The microstructure at arrested fatigue cracks on the free surface was compared to the microstructure found beneath striations on the fracture surfaces by utilizing FIB micromachining to create site-specific TEM samples. The evolved microstructure depended on the slip type. Strong agreement was found between the crack tip microstructure at the free surface and the fracture surface. In the planar materials, the microstructure in the plastic zone consisted of bands of dislocations or deformation twins, before transitioning to a refined sub-grain microstructure near the crack flank. The sub-grain structure extended 300-500 nm away from the crack flank in all the planar slip materials studied. In contrast, the bulk structure in the wavy slip material consisted of dislocation cells and did not transition to a different microstructure as the crack tip was approached. The strain in wavy slip was highest near the crack tip, as the misorientations between the dislocation cells increased and the cell size decreased as the crack flank was approached. The final set of experiments involved reloading the arrested crack tips in monotonic tension. This was performed on both the Haynes 230 and 316 stainless steel. This technique exposed the fracture surface and location of the arrested crack tip away from the free surface, allowing for a sample to be extracted via FIB micromachining and TEM evaluation of the microstructure. This permitted the crack tip microstructure to be investigated without exposing the microstructure to crack closure or free surface effects. These experiments confirmed what was inferred from the earlier experiments, namely that the banded structure was a product of the crack tip plastic zone and the refined structure was a product of the strain associated with crack advance. Overall the microstructural complexity presented in this work was much higher than would be predicted by current models of fatigue crack propagation. It is recommended that future models attempt to simulate interactions between the dislocations emitted during fatigue crack growth and the pre-existing microstructure to more accurately simulate the processes occurring at the crack tip during crack growth.

The materials irradiation experiment for testing plasma facing materials at fusion relevant conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garrison, L. M., E-mail: garrisonlm@ornl.gov; Egle, B. J.; Fusion Technology Institute, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, Wisconsin 53706

2016-08-15

The Materials Irradiation Experiment (MITE-E) was constructed at the University of Wisconsin-Madison Inertial Electrostatic Confinement Laboratory to test materials for potential use as plasma-facing materials (PFMs) in fusion reactors. PFMs in fusion reactors will be bombarded with x-rays, neutrons, and ions of hydrogen and helium. More needs to be understood about the interactions between the plasma and the materials to validate their use for fusion reactors. The MITE-E simulates some of the fusion reactor conditions by holding samples at temperatures up to 1000 °C while irradiating them with helium or deuterium ions with energies from 10 to 150 keV. The ionmore » gun can irradiate the samples with ion currents of 20 μA–500 μA; the typical current used is 72 μA, which is an average flux of 9 × 10{sup 14} ions/(cm{sup 2} s). The ion gun uses electrostatic lenses to extract and shape the ion beam. A variable power (1-20 W), steady-state, Nd:YAG laser provides additional heating to maintain a constant sample temperature during irradiations. The ion beam current reaching the sample is directly measured and monitored in real-time during irradiations. The ion beam profile has been investigated using a copper sample sputtering experiment. The MITE-E has successfully been used to irradiate polycrystalline and single crystal tungsten samples with helium ions and will continue to be a source of important data for plasma interactions with materials.« less

Novel experimental methods for investigating high speed friction of titanium-aluminum-vanadium/tool steel interface and dynamic failure of extrinsically toughened DRA composites

NASA Astrophysics Data System (ADS)

Irfan, Mohammad Abdulaziz

Dynamic deformation, flow, and failure are integral parts of all dynamic processes in materials. Invariably, dynamic failure also involves the relative sliding of one component of the material over the other. Advances in elucidation of these failure mechanisms under high loading rates has been of great interest to scientists working in this area. The need to develop new dynamic mechanical property tests for materials under well characterized and controllable loading conditions has always been a challenge to experimentalists. The current study focuses on the development of two experimental methods to study some aspects of dynamic material response. The first part focuses on the development of a single stage gas gun facility for investigating high-speed metal to metal interfacial friction with applications to high speed machining. During the course of this investigation a gas gun was designed and built capable of accelerating projectiles upto velocities of 1 km/s. Using this gas gun pressure-shear plate impact friction experiments were conducted to simulate conditions similar to high speed machining at the tool-workpiece interface. The impacting plates were fabricated from materials representing the tribo-pair of interest. Accurate measurements of the interfacial tractions, i.e. the normal pressure and the frictional stress at the tribo-pair interface, and the interfacial slip velocity could be made by employing laser interferometry. Normal pressures of the order of 1-2 MPa were generated and slipping velocities of the order of 50 m/s were obtained. In order to illustrate the structure of the constitutive law governing friction, the study included experimental investigation of frictional response to step changes in normal pressure and interfacial shear stress. The results of these experiments indicate that sliding resistance for Ti6Al4V/CH steel interface is much lower than measured under quasi-static sliding conditions. Also the temperature at the interface strongly effects the sliding resistance of the interface. The experimental results deduced from the response of the sliding interface to step changes in normal pressure and the applied shear stress reinforce the importance of including frictional memory in the development of rate dependent state variable friction models. The second part of the thesis presents an investigation into the dynamic deformation and failure of extrinsically toughened DRA composites. Experiments were conducted using the split Hopkinson pressure bar to investigate the deformation and flow behavior under dynamic compression loading. A modified Hopkinson bar apparatus was used to explore the dynamic fracture behavior of three different extrinsically toughened DRA composites. The study was paralleled by systematic exploration of the failure modes in each composite. For all the composites evaluated the dynamic crack propagation characteristics of the composites are observed to be strongly dependent on the volume fraction of the ductile phase reinforcement in the composite, the yield stress of the ductile phase reinforcement, the micro-structural arrangement of the ductile phase reinforcements with respect to the notch, and the impact velocity employed in the particular experiment.

The BIMDA shuttle flight mission - A low cost MPS payload

NASA Technical Reports Server (NTRS)

Holemans, Jaak; Cassanto, John M.; Morrison, Dennis; Rose, Alan; Luttges, Marvin

1990-01-01

The design, operation, and experimental protocol of the Bioserve-ITA Materials Dispersion Apparatus Payload (BIMDA) to be flown on the Space Shuttle on STS-37 are described. The aim of BIMDA is to investigate the methods and commercial potential of biomedical and fluid science applications in the microgravity environment. The BIMDA payload operations are diagrammed, and the payload components and experiments are listed, including the investigators and sponsoring institutions.

Investigation of Electric and Self-Generated Magnetic Fields in Implosion Experiments on OMEGA

NASA Astrophysics Data System (ADS)

Igumenshchev, I. V.; Nilson, P. M.; Goncharov, V. N.; Li, C. K.; Zylstra, A. B.; Petrasso, R. D.

2013-10-01

Electric and self-generated magnetic fields in direct-drive implosion experiments on the OMEGA laser were investigated using proton radiography. The experiments use plastic-shell targets with various surface defects (glue spot, wire, and stalk mount) to seed perturbations and generate localized electromagnetic fields at the ablation surface and in the plasma corona surrounding the targets. Proton radiographs show features from these perturbations and quasi-spherical multiple shell structures around the capsules at earlier times of implosions (up to ~700 ps for a 1-ns laser pulse) indicating the development of the fields. Two-dimensional magnetohydrodynamic simulations of these experiments predict the growth of magnetic fields up to several MG. The simulated distributions of electromagnetic fields were used to produce proton images, which show good agreement with experimental radiographs. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

Sediment dynamics in the Adriatic Sea investigated with coupled models

USGS Publications Warehouse

Sherwood, Christopher R.; Book, Jeffrey W.; Carniel, Sandro; Cavaleri, Luigi; Chiggiato, Jacopo; Das, Himangshu; Doyle, James D.; Harris, Courtney K.; Niedoroda, Alan W.; Perkins, Henry; Poulain, Pierre-Marie; Pullen, Julie; Reed, Christopher W.; Russo, Aniello; Sclavo, Mauro; Signell, Richard P.; Traykovski, Peter A.; Warner, John C.

2004-01-01

Several large research programs focused on the Adriatic Sea in winter 2002-2003, making it an exciting place for sediment dynamics modelers (Figure 1). Investigations of atmospheric forcing and oceanic response (including wave generation and propagation, water-mass formation, stratification, and circulation), suspended material, bottom boundary layer dynamics, bottom sediment, and small-scale stratigraphy were performed by European and North American researchers participating in several projects. The goal of EuroSTRATAFORM researchers is to improve our ability to understand and simulate the physical processes that deliver sediment to the marine environment and generate stratigraphic signatures. Scientists involved in the Po and Apennine Sediment Transport and Accumulation (PASTA) experiment benefited from other major research programs including ACE (Adriatic Circulation Experiment), DOLCE VITA (Dynamics of Localized Currents and Eddy Variability in the Adriatic), EACE (the Croatian East Adriatic Circulation Experiment project), WISE (West Istria Experiment), and ADRICOSM (Italian nowcasting and forecasting) studies.

Pixel detectors in double beta decay experiments, a new approach for background reduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jose, J. M.; Čermák, P.; Štekl, I.

Double beta decay (ββ) experiments are challenging frontiers in contemporary physics. These experiments have the potential to investigate more about neutrinos (eg. nature and mass). The main challenge for these experiments is the reduction of background. The group at IEAP, CTU in Prague is investigating a new approach using pixel detectors Timepix. Pixel detector offer background reduction capabilities with its ability to identify the particle interaction (from the 2D signature it generates). However, use of pixel detectors has some challenges such as the presence of readout electronics near the sensing medium and heat dissipation. Different aspects of pixel setup (identificationmore » of radio-impurities, selection of radio-pure materials) and proposed experimental setup are presented. Also, results of preliminary background measurements (performed on the surface and in the underground laboratories) using the prototype setups are presented.« less

A tribological and biomimetic study of potential bone joint repair materials

NASA Astrophysics Data System (ADS)

Ribeiro, Rahul

This research investigates materials for bone-joint failure repair using tribological and biomimicking approaches. The materials investigated represent three different repairing strategies. Refractory metals with and without treatment are candidates for total joint replacements due to their mechanical strength, high corrosion resistance and biocompatibility. A composite of biodegradable polytrimethylene carbonate, hydroxyl apatite, and nanotubes was investigated for application as a tissue engineering scaffold. Non-biodegradable polymer polyimide combined with various concentrations of nanotubes was investigated as a cartilage replacement material. A series of experimental approaches were used in this research. These include analysis of material surfaces and debris using high-resolution techniques and tribological experiments, as well as evaluation of nanomechanical properties. Specifically, the surface structure and wear mechanisms were investigated using a scanning electron microscope and an atomic force microscope. Debris morphology and structure was investigated using a transmission electron microscope. The debris composition was analyzed using an X-ray diffractometer. Nanoindentation was incorporated to investigate the surface nanomechanical properties. Polytrimythelene carbonate combined with hydroxyapatite and nanotubes exhibited a friction coefficient lower than UHMWPE. The nanoindentation response mimicked cartilage more closely than UHMWPE. A composite formed with PI and nanotubes showed a varying friction coefficient and varying nanoindentation response with variation in nanotube concentration. Low friction coefficients corresponded with low modulus values. A theory was proposed to explain this behavior based on surface interactions between nanotubes and between nanotubes and PI. A model was developed to simulate the modulus as a function of nanotube concentration. The boronized refractory metals exhibited brittleness and cracking. Higher friction coefficients were associated with the formation of amorphous debris. The friction coefficient for boronized Cr (˜0.06) under simulated body fluid conditions was in the range found in natural joints.

Polarization ratio property and material classification method in passive millimeter wave polarimetric imaging

NASA Astrophysics Data System (ADS)

Cheng, Yayun; Qi, Bo; Liu, Siyuan; Hu, Fei; Gui, Liangqi; Peng, Xiaohui

2016-10-01

Polarimetric measurements can provide additional information as compared to unpolarized ones. In this paper, linear polarization ratio (LPR) is created to be a feature discriminator. The LPR properties of several materials are investigated using Fresnel theory. The theoretical results show that LPR is sensitive to the material type (metal or dielectric). Then a linear polarization ratio-based (LPR-based) method is presented to distinguish between metal and dielectric materials. In order to apply this method to practical applications, the optimal range of incident angle have been discussed. The typical outdoor experiments including various objects such as aluminum plate, grass, concrete, soil and wood, have been conducted to validate the presented classification method.

Non-destructive inspection approach using ultrasound to identify the material state for amorphous and semi-crystalline materials

NASA Astrophysics Data System (ADS)

Jost, Elliott; Jack, David; Moore, David

2018-04-01

At present, there are many methods to identify the temperature and phase of a material using invasive techniques. However, most current methods require physical contact or implicit methods utilizing light reflectance of the specimen. This work presents a nondestructive inspection method using ultrasonic wave technology that circumvents these disadvantages to identify phase change regions and infer the temperature state of a material. In the present study an experiment is performed to monitor the time of flight within a wax as it undergoes melting and the subsequent cooling. Results presented in this work show a clear relationship between a material's speed of sound and its temperature. The phase change transition of the material is clear from the time of flight results, and in the case of the investigated material, this change in the material state occurs over a range of temperatures. The range of temperatures over which the wax material melts is readily identified by speed of sound represented as a function of material temperature. The melt temperature, obtained acoustically, is validated using Differential Scanning Calorimetry (DSC), which uses shifts in heat flow rates to identify phase transition temperature ranges. The investigated ultrasonic NDE method has direct applications in many industries, including oil and gas, food and beverage, and polymer composites, in addition to many implications for future capabilities of nondestructive inspection of multi-phase materials.

Analog and numerical experiments investigating force chain influences on bed conditions in granular flows

NASA Astrophysics Data System (ADS)

Estep, J.; Dufek, J.

2013-12-01

Granular flows are fundamental processes in several terrestrial and planetary natural events; including surficial flows on volcanic edifices, debris flows, landslides, dune formation, rock falls, sector collapses, and avalanches. Often granular flows can be two-phase, whereby interstitial fluids occupy void space within the particulates. The mobility of granular flows has received significant attention, however the physics that govern their internal behavior remain poorly understood. Here we extend upon previous research showing that force chains can transmit extreme localized forces to the substrates of free surface granular flows, and we combine experimental and computational approaches to further investigate the forces at the bed of simplified granular flows. Analog experiments resolve discrete bed forces via a photoelastic technique, while numerical experiments validate laboratory tests using discrete element model (DEM) simulations. The current work investigates (1) the role of distributed grain sizes on force transmission via force chains, and (2) how the inclusion of interstitial fluids effects force chain development. We also include 3D numerical simulations to apply observed 2D characteristics into real world perspective, and ascertain if the added dimension alters force chain behavior. Previous research showed that bed forces generated by force chain structures can transiently greatly exceed (by several 100%) the bed forces predicted from continuum approaches, and that natural materials are more prone to excessive bed forces than photoelastic materials due to their larger contact stiffnesses. This work suggests that force chain activity may play an important role in the bed physics of dense granular flows by influencing substrate entrainment. Photoelastic experiment image showing force chains in gravity driven granular flow.

Flat-plate solar array project. Task 1: Silicon material. Investigation of the hydrochlorination of SiC14

NASA Technical Reports Server (NTRS)

Mui, J. Y. P.

1982-01-01

A two inch diameter stainless steel reactor was designed and built to operate at pressures up to 500 psig for the experimental studies on the hydrochlorination of SiCl4 and metallurgical grade (m.g.) silicon metal to SiHCl3. In order to clearly see the effect of pressure, the experiments were carried out at low reactor pressures of 73 psig and 150 psig, respectively. A large pressure effect on the hydrochlorination reaction was observed between the results of the low pressure experiments and the results of the high pressure experiments. In general, higher pressure produces a higher conversion of SiHCl3, but at a lower reaction rate. The effect of temperature on the reaction rate was studied at 73 psig. Higher reaction temperature gave a higher conversion and a higher reaction rate. Samples of the materials used to construct the hydrochlorination reactor were prepared for corrosion tests.

Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makowska, Małgorzata G.; Theil Kuhn, Luise; Cleemann, Lars N.

In high material penetration by neutrons allows for experiments using sophisticated sample environments providing complex conditions. Thus, neutron imaging holds potential for performing in situ nondestructive measurements on large samples or even full technological systems, which are not possible with any other technique. Our paper presents a new sample environment for in situ high resolution neutron imaging experiments at temperatures from room temperature up to 1100 degrees C and/or using controllable flow of reactive atmospheres. The design also offers the possibility to directly combine imaging with diffraction measurements. Design, special features, and specification of the furnace are described. In addition,more » examples of experiments successfully performed at various neutron facilities with the furnace, as well as examples of possible applications are presented. Our work covers a broad field of research from fundamental to technological investigations of various types of materials and components.« less

Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere

DOE PAGES

Makowska, Małgorzata G.; Theil Kuhn, Luise; Cleemann, Lars N.; ...

2015-12-17

In high material penetration by neutrons allows for experiments using sophisticated sample environments providing complex conditions. Thus, neutron imaging holds potential for performing in situ nondestructive measurements on large samples or even full technological systems, which are not possible with any other technique. Our paper presents a new sample environment for in situ high resolution neutron imaging experiments at temperatures from room temperature up to 1100 degrees C and/or using controllable flow of reactive atmospheres. The design also offers the possibility to directly combine imaging with diffraction measurements. Design, special features, and specification of the furnace are described. In addition,more » examples of experiments successfully performed at various neutron facilities with the furnace, as well as examples of possible applications are presented. Our work covers a broad field of research from fundamental to technological investigations of various types of materials and components.« less

Results of the Experiment: Welding of Aluminium Alloy in Microgravity

NASA Astrophysics Data System (ADS)

Ferretti, S.; Amadori, K.; Boccalatte, A.; Alessandrini, M.; Freddi, A.; Persiani, F.; Poli, G.

2002-01-01

An experiment on "dendritic growth in aluminium alloy welding" was performed by the UNIBO team during the 3rd Student Parabolic Flight Campaign and the 30th Professional Parabolic Flight Campaign organised by ESA. Its purpose was to achieve a better understanding of crystal growth during tungsten inert gas (TIG) welding of an aluminium alloy to define the main parameters affecting the process under microgravity condition. The experiment had 4 phases : The paper discusses different aspects of the research, paying particularly attention not only to the influence of gravity, but also to other factors influencing welding microstructure, such as the Marangoni effect and the thermal transfer from the electrode to the material. The paper conclude the dissertation of the results offering new perspectives for welding studies and proposing a new approach to the scientific community to investigate this materials processes for manufacturing.

Experimental studies on metallic fuel relocation in a single-pin core structure of a sodium-cooled fast reactor

DOE PAGES

Kim, Taeil; Harbaruk, Dzmitry; Gerardi, Craig; ...

2017-07-10

Experiments dropping molten uranium into test sections of single fuel pin geometry filled with sodium were conducted to investigate relocation behavior of metallic fuel in the core structures of sodium-cooled fast reactors during a hypothetical core disruptive accident. Metallic uranium was used as a fuel material and HT-9M was used as a fuel cladding material in the experiment in order to accurately mock-up the thermo-physical behavior of the relocation. The fuel cladding failed due to eutectic formation between the uranium and HT-9M for all experiments. The extent of the eutectic formation increased with increasing molten uranium temperature. Voids in themore » relocated fuel were observed for all experiments and were likely formed by sodium boiling in contact with the fuel. In one experiment, numerous fragments of the relocated fuel were found. In conclusion, it could be concluded that the injected metallic uranium fuel was fragmented and dispersed in the narrow coolant channel by sodium boiling« less

Experimental studies on metallic fuel relocation in a single-pin core structure of a sodium-cooled fast reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Taeil; Harbaruk, Dzmitry; Gerardi, Craig

Experiments dropping molten uranium into test sections of single fuel pin geometry filled with sodium were conducted to investigate relocation behavior of metallic fuel in the core structures of sodium-cooled fast reactors during a hypothetical core disruptive accident. Metallic uranium was used as a fuel material and HT-9M was used as a fuel cladding material in the experiment in order to accurately mock-up the thermo-physical behavior of the relocation. The fuel cladding failed due to eutectic formation between the uranium and HT-9M for all experiments. The extent of the eutectic formation increased with increasing molten uranium temperature. Voids in themore » relocated fuel were observed for all experiments and were likely formed by sodium boiling in contact with the fuel. In one experiment, numerous fragments of the relocated fuel were found. In conclusion, it could be concluded that the injected metallic uranium fuel was fragmented and dispersed in the narrow coolant channel by sodium boiling« less

KSC-97PC1380

NASA Image and Video Library

1997-09-08

United States Microgravity Payload-4 (USMP-4) experiments are prepared to be flown on Space Shuttle mission STS-87 in the Space Station Processing Facility at Kennedy Space Center (KSC). Seen at right in the circular white cover is the Isothermal Dendritic Growth Experiment (IDGE), which will be used to study the dendritic solidification of molten materials in the microgravity environment. The large white vertical cylinder in the center of the photo is the Advanced Automated Directional Solidification Furnace (AADSF) and the horizontal tube to the left of it is MEPHISTO, a French acronym for a cooperative American-French investigation of the fundamentals of crystal growth. Just below MEPHISTO is the Space Acceleration Measurement System, or SAMS, which measures the microgravity conditions in which the experiments are conducted. The The metallic breadbox-like structure behind the AADSF is the Confined Helium Experiment (CHeX) that will study one of the basic influences on the behavior and properties of materials by using liquid helium confined between solid surfaces and microgravity. All of these experiments are scheduled for launch aboard STS-87 on Nov. 19 from KSC

Enhanced efficiency of solid-state NMR investigations of energy materials using an external automatic tuning/matching (eATM) robot.

PubMed

Pecher, Oliver; Halat, David M; Lee, Jeongjae; Liu, Zigeng; Griffith, Kent J; Braun, Marco; Grey, Clare P

2017-02-01

We have developed and explored an external automatic tuning/matching (eATM) robot that can be attached to commercial and/or home-built magic angle spinning (MAS) or static nuclear magnetic resonance (NMR) probeheads. Complete synchronization and automation with Bruker and Tecmag spectrometers is ensured via transistor-transistor-logic (TTL) signals. The eATM robot enables an automated "on-the-fly" re-calibration of the radio frequency (rf) carrier frequency, which is beneficial whenever tuning/matching of the resonance circuit is required, e.g. variable temperature (VT) NMR, spin-echo mapping (variable offset cumulative spectroscopy, VOCS) and/or in situ NMR experiments of batteries. This allows a significant increase in efficiency for NMR experiments outside regular working hours (e.g. overnight) and, furthermore, enables measurements of quadrupolar nuclei which would not be possible in reasonable timeframes due to excessively large spectral widths. Additionally, different tuning/matching capacitor (and/or coil) settings for desired frequencies (e.g. 7 Li and 31 P at 117 and 122MHz, respectively, at 7.05 T) can be saved and made directly accessible before automatic tuning/matching, thus enabling automated measurements of multiple nuclei for one sample with no manual adjustment required by the user. We have applied this new eATM approach in static and MAS spin-echo mapping NMR experiments in different magnetic fields on four energy storage materials, namely: (1) paramagnetic 7 Li and 31 P MAS NMR (without manual recalibration) of the Li-ion battery cathode material LiFePO 4 ; (2) paramagnetic 17 O VT-NMR of the solid oxide fuel cell cathode material La 2 NiO 4+δ ; (3) broadband 93 Nb static NMR of the Li-ion battery material BNb 2 O 5 ; and (4) broadband static 127 I NMR of a potential Li-air battery product LiIO 3 . In each case, insight into local atomic structure and dynamics arises primarily from the highly broadened (1-25MHz) NMR lineshapes that the eATM robot is uniquely suited to collect. These new developments in automation of NMR experiments are likely to advance the application of in and ex situ NMR investigations to an ever-increasing range of energy storage materials and systems. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Enhanced efficiency of solid-state NMR investigations of energy materials using an external automatic tuning/matching (eATM) robot

NASA Astrophysics Data System (ADS)

Pecher, Oliver; Halat, David M.; Lee, Jeongjae; Liu, Zigeng; Griffith, Kent J.; Braun, Marco; Grey, Clare P.

2017-02-01

We have developed and explored an external automatic tuning/matching (eATM) robot that can be attached to commercial and/or home-built magic angle spinning (MAS) or static nuclear magnetic resonance (NMR) probeheads. Complete synchronization and automation with Bruker and Tecmag spectrometers is ensured via transistor-transistor-logic (TTL) signals. The eATM robot enables an automated "on-the-fly" re-calibration of the radio frequency (rf) carrier frequency, which is beneficial whenever tuning/matching of the resonance circuit is required, e.g. variable temperature (VT) NMR, spin-echo mapping (variable offset cumulative spectroscopy, VOCS) and/or in situ NMR experiments of batteries. This allows a significant increase in efficiency for NMR experiments outside regular working hours (e.g. overnight) and, furthermore, enables measurements of quadrupolar nuclei which would not be possible in reasonable timeframes due to excessively large spectral widths. Additionally, different tuning/matching capacitor (and/or coil) settings for desired frequencies (e.g.7Li and 31P at 117 and 122 MHz, respectively, at 7.05 T) can be saved and made directly accessible before automatic tuning/matching, thus enabling automated measurements of multiple nuclei for one sample with no manual adjustment required by the user. We have applied this new eATM approach in static and MAS spin-echo mapping NMR experiments in different magnetic fields on four energy storage materials, namely: (1) paramagnetic 7Li and 31P MAS NMR (without manual recalibration) of the Li-ion battery cathode material LiFePO4; (2) paramagnetic 17O VT-NMR of the solid oxide fuel cell cathode material La2NiO4+δ; (3) broadband 93Nb static NMR of the Li-ion battery material BNb2O5; and (4) broadband static 127I NMR of a potential Li-air battery product LiIO3. In each case, insight into local atomic structure and dynamics arises primarily from the highly broadened (1-25 MHz) NMR lineshapes that the eATM robot is uniquely suited to collect. These new developments in automation of NMR experiments are likely to advance the application of in and ex situ NMR investigations to an ever-increasing range of energy storage materials and systems.

Application of ToF-SIMS to the study of surfactant removal from AuNbMCM-41 and AuMCM-41 materials

NASA Astrophysics Data System (ADS)

Grams, Jacek; Sobczak, Izabela

2010-01-01

This work is focused on the application of time-of-flight secondary ion mass spectrometry (ToF-SIMS) in investigation of the surfactant removal process from AuNbMCM-41 and AuMCM-41 catalysts (MCM-41 "Mobil Composition of Matter", ordered mesoporous materials discovered by Mobil R&D Corporation). The samples investigated were prepared by co-precipitation in the presence of a cationic surfactant (cetyltrimethylammonium chloride--CH3(CH2)15N(Cl)(CH3)3) and the incipient wetness impregnation methods. The results obtained showed that the time-of-flight secondary ion mass spectrometry appears to be a very useful tool for the investigation of the residual organic template on the surface of ordered mesoporous materials of MCM-41 type. It was demonstrated that the calcination of AuNbMCM-41 and AuMCM-41 catalysts at 550 °C caused a complete removal of the surfactant from the surface of the material investigated. Moreover, it was shown that the use of bismuth liquid metal ion gun in ToF-SIMS experiments permitted obtaining higher emission intensity (more than one order of magnitude when compared to the Ga+ primary ion source) of secondary ions originating from the surfactant molecules and may facilitate an interpretation of the results obtained.

Interculturality and the Study Abroad Experience: Students' Learning from the IEREST Materials

ERIC Educational Resources Information Center

Holmes, Prue; Bavieri, Luisa; Ganassin, Sara; Murphy, Jonathon

2016-01-01

This study investigated how a "while abroad" (IEREST) intercultural experiential learning programme (i) encouraged mobile student sojourners to explore the concept of "interculturality"; (ii) promoted their intercultural engagement/communication during their stay abroad; and (iii) invited them to reflect on their own…

Inquiry-based Investigation in Biology Laboratories: Does Neem Provide Bioprotection against Bean Beetles?

ERIC Educational Resources Information Center

Pearce, Amy R.; Sale, Amanda Lovelace; Srivatsan, Malathi; Beck, Christopher W.; Blumer, Lawrence S.; Grippo, Anne A.

2013-01-01

We developed an inquiry-based biology laboratory exercise in which undergraduate students designed experiments addressing whether material from the neem tree ("Azadirachta indica") altered bean beetle ("Callosobruchus maculatus") movements and oviposition. Students were introduced to the bean beetle life cycle, experimental…

A Simple Measurement of the Sliding Friction Coefficient

ERIC Educational Resources Information Center

Gratton, Luigi M.; Defrancesco, Silvia

2006-01-01

We present a simple computer-aided experiment for investigating Coulomb's law of sliding friction in a classroom. It provides a way of testing the possible dependence of the friction coefficient on various parameters, such as types of materials, normal force, apparent area of contact and sliding velocity.

New Titan Saltation Threshold Experiments: Investigating Current and Past Climates

NASA Astrophysics Data System (ADS)

Bridges, N.; Burr, D. M.; Marshall, J.; Smith, J. K.; Emery, J. P.; Horst, S. M.; Nield, E.; Yu, X.

2015-12-01

Titan exhibits aeolian sand dunes that cover ~20% of its surface, attesting to significant sediment transport by the wind. Recent experiments in the Titan Wind Tunnel (TWT) at NASA Ames Research Center [1,2] found that the threshold friction speed needed to detach Titanian "sand" is about 50% higher than previous estimates based on theory alone [3], a result that might be explained by the low ratio of particle to fluid density on the body [1]. Following the successful completion of the initial Titan threshold tests, we are conducting new experiments that expand the pressure range above and below current Titan values. The basic experimental techniques are described in [1], with minor updates to the instrumentation as described in [2]. To reproduce the kinematic viscosity and particle friction Reynolds number equivalent to that expected for Titan's nitrogen atmosphere at 1.4 bars and 94 K requires that TWT be pressurized to 12.5 bars for air at 293K. In addition to running experiments at this pressure to reproduce previous results [1] and investigate low density (high density ratio) materials, TWT pressures of 3 and 8 bars are in the experimental matrix to understand threshold under past Titan conditions when the atmospheric pressure may have been lower [4]. Higher pressures, at 15 and 20 bars in TWT, are also being run to understand the putative effects of low density ratio conditions. Our experimental matrix for this follow-on work uses some of the same materials as previously used, including walnut shells, basalt, quartz, glass spheres, and various low density materials to better simulate the gravity-equivalent weight of Titan sand. For these experiments, the TWT is now equipped with a new high pressure Tavis transducer with sufficient sensitivity to measure freestream speeds of less than 0.5 m s-1 at 12.5 bars. New techniques include video documentation of the experiments. We are also investigating methods of measuring humidity of the wind tunnel environment and electrostatic forces to assess their effect on threshold. [1] Burr, D.M. et al. [2015], Nature, 517, 60-67. [2] Burr, D.M. et al. [2015], Aeolian Res., in press [3] Iversen, J.D. and B.R. White (1982), Sedimentology, 29, 111-119. [4] Charnay, B. et al. [2014], Icarus, 241, 269-279.

Surface instabilities in shock loaded granular media

NASA Astrophysics Data System (ADS)

Kandan, K.; Khaderi, S. N.; Wadley, H. N. G.; Deshpande, V. S.

2017-12-01

The initiation and growth of instabilities in granular materials loaded by air shock waves are investigated via shock-tube experiments and numerical calculations. Three types of granular media, dry sand, water-saturated sand and a granular solid comprising PTFE spheres were experimentally investigated by air shock loading slugs of these materials in a transparent shock tube. Under all shock pressures considered here, the free-standing dry sand slugs remained stable while the shock loaded surface of the water-saturated sand slug became unstable resulting in mixing of the shocked air and the granular material. By contrast, the PTFE slugs were stable at low pressures but displayed instabilities similar to the water-saturated sand slugs at higher shock pressures. The distal surfaces of the slugs remained stable under all conditions considered here. Eulerian fluid/solid interaction calculations, with the granular material modelled as a Drucker-Prager solid, reproduced the onset of the instabilities as seen in the experiments to a high level of accuracy. These calculations showed that the shock pressures to initiate instabilities increased with increasing material friction and decreasing yield strain. Moreover, the high Atwood number for this problem implied that fluid/solid interaction effects were small, and the initiation of the instability is adequately captured by directly applying a pressure on the slug surface. Lagrangian calculations with the directly applied pressures demonstrated that the instability was caused by spatial pressure gradients created by initial surface perturbations. Surface instabilities are also shown to exist in shock loaded rear-supported granular slugs: these experiments and calculations are used to infer the velocity that free-standing slugs need to acquire to initiate instabilities on their front surfaces. The results presented here, while in an idealised one-dimensional setting, provide physical understanding of the conditions required to initiate instabilities in a range of situations involving the explosive dispersion of particles.

Structural Reorganization of CNC in Injection-Molded CNC/PBAT Materials under Thermal Annealing.

PubMed

Mariano, Marcos; El Kissi, Nadia; Dufresne, Alain

2016-10-04

Composite materials were prepared by extrusion and injection molding from polybutyrate adipate terephthalate (PBAT) and high aspect ratio cellulose nanocrystals (CNCs) extracted from capim dourado fibers. Three CNC contents were used, corresponding to 0.5, 1, and 2 times the theoretical percolation threshold. Small-amplitude oscillary shear (SAOS) experiments show that as the CNC content increases, a more elastic behavior is observed but no percolating network can form within the polymeric matrix as a result of the high shear rates involved during the injection-molding process. Annealing of the samples at 170 °C was performed, and the possible reorganization of the nanofiller was investigated. This reorganization was further elucidated using 2D-SAOS and creep experiments.

High-speed imaging of inhomogeneous ignition in a shock tube

NASA Astrophysics Data System (ADS)

Tulgestke, A. M.; Johnson, S. E.; Davidson, D. F.; Hanson, R. K.

2018-05-01

Homogeneous and inhomogeneous ignition of real and surrogate fuels were imaged in two Stanford shock tubes, revealing the influence of small particle fragmentation. n-Heptane, iso-octane, and Jet A were studied, each mixed in an oxidizer containing 21% oxygen and ignited at low temperatures (900-1000 K), low pressures (1-2 atm), with an equivalence ratio of 0.5. Visible images (350-1050 nm) were captured through the shock tube endwall using a high-speed camera. Particles were found to arrive near the endwalls of the shock tubes approximately 5 ms after reflection of the incident shock wave. Reflected shock wave experiments using diaphragm materials of Lexan and steel were investigated. Particles collected from the shock tubes after each experiment were found to match the material of the diaphragm burst during the experiment. Following each experiment, the shock tubes were cleaned by scrubbing with cotton cloths soaked with acetone. Particles were observed to fragment after arrival near the endwall, often leading to inhomogeneous ignition of the fuel. Distinctly more particles were observed during experiments using steel diaphragms. In experiments exhibiting inhomogeneous ignition, flames were observed to grow radially until all the fuel within the cross section of the shock tube had been consumed. The influence of diluent gas (argon or helium) was also investigated. The use of He diluent gas was found to suppress the number of particles capable of causing inhomogeneous flames. The use of He thus allowed time history studies of ignition to extend past the test times that would have been limited by inhomogeneous ignition.

The High Energy Materials Science Beamline (HEMS) at PETRA III

NASA Astrophysics Data System (ADS)

Schell, Norbert; King, Andrew; Beckmann, Felix; Ruhnau, Hans-Ulrich; Kirchhof, René; Kiehn, Rüdiger; Müller, Martin; Schreyer, Andreas

2010-06-01

The HEMS Beamline at the German high-brilliance synchrotron radiation storage ring PETRA III is fully tunable between 30 and 250 keV and optimized for sub-micrometer focusing. Approximately 70 % of the beamtime will be dedicated to Materials Research. Fundamental research will encompass metallurgy, physics and chemistry with first experiments planned for the investigation of the relationship between macroscopic and micro-structural properties of polycrystalline materials, grain-grain-interactions, and the development of smart materials or processes. For this purpose a 3D-microsctructure-mapper has been designed. Applied research for manufacturing process optimization will benefit from high flux in combination with ultra-fast detector systems allowing complex and highly dynamic in-situ studies of micro-structural transformations, e.g. during welding processes. The beamline infrastructure allows accommodation of large and heavy user provided equipment. Experiments targeting the industrial user community will be based on well established techniques with standardized evaluation, allowing full service measurements, e.g. for tomography and texture determination. The beamline consists of a five meter in-vacuum undulator, a general optics hutch, an in-house test facility and three independent experimental hutches working alternately, plus additional set-up and storage space for long-term experiments. HEMS is under commissioning as one of the first beamlines running at PETRA III.

Experiment module concepts study. Volume 2: Experiments and mission operations

NASA Technical Reports Server (NTRS)

Macdonald, J. M.

1970-01-01

The baseline experiment program is concerned with future space experiments and cover the scientific disciplines of astronomy, space physics, space biology, biomedicine and biotechnology, earth applications, materials science, and advanced technology. The experiments within each discipline are grouped into functional program elements according to experiments that support a particular area of research or investigation and experiments that impose similar or related demand on space station support systems. The experiment requirements on module subsystems, experiment operating modes and time profiles, and the role of the astronaut are discussed. Launch and rendezvous with the space station, disposal, and on-orbit operations are delineated. The operational interfaces between module and other system elements are presented and include space station and logistic system interfaces. Preliminary launch and on-orbit environmental criteria and requirements are discussed, and experiment equipment weights by functional program elements are tabulated.

Shock Response and Explosive Launch of Compacted Reactive Material

NASA Astrophysics Data System (ADS)

Molitoris, John; Gash, Alexander; Garza, Raul; Gagliardi, Franco; Tringe, Joseph; Batteux, Jan; Souers, P.; HEAF Team

2013-06-01

We have performed a series of experiments investigating the detailed dynamic response of compacted reactive material to shock and blast. Here a granular reactive formulation (Fe2O3/Al based thermite) was pressed into a solid cylinder of material and mated to a high-explosive charge of the same diameter. Detonation of the charge transmitted a shock wave to the thermite cylinder and imparted momentum launching it in the direction of the detonation. High-resolution time sequence radiography was used to image the dynamic response of the thermite. This technique allowed a detailed investigation of material deformation in addition to changes in the internal structure and indications of reactivity. The effect of variations in the initial density of the pressed thermite was also examined. We find that these pressed thermites behave much like solid metals during shock transit, then respond much differently. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

FGD liner experiments with wetlands

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mitsch, W.J.; Ahn, C.; Wolfe, W.E.

1999-07-01

The construction of artificial wetlands for wastewater treatment often requires impermeable liners not only to protect groundwater resources but also to ensure that there is adequate water in the wetland to support appropriate aquatic life, particularly wetland vegetation. Liners or relatively impervious site soils are very important to the success of constructed treatment wetlands in areas where ground water levels are typically close to the ground surface. This study, carried out at the Olentangy River Wetland Research Park, investigated the use of FGD material from sulfur scrubbers as a possible liner material for constructed wetlands. While several studies have investigatedmore » the use of FGD material to line ponds, no studies have investigated the use of this material as a liner for constructed wetlands. They used experimental mesocosms to see the effect of FGD liner materials in constructed wetlands on water quality and on wetland plant growth. This paper presents the results of nutrient analyses and physicochemical investigation of leachate and surface outflow water samples collected from the mesocosms. Plant growth and biomass of wetland vegetation are also included in this paper. First two year results are reported by Ahn et al. (1998, 1999). The overall goal of this study is the identification of advantages and disadvantages of using FGD by-product as an artificial liner in constructed wetlands.« less

Liquid cooling applications on automotive exterior LED lighting

NASA Astrophysics Data System (ADS)

Aktaş, Mehmet; Şenyüz, Tunç; Şenyıldız, Teoman; Kılıç, Muhsin

2018-02-01

In this study cooling of a LED unit with heatsink and liquid cooling block which is used in automotive head lamp applications has been investigated numerically and experimentally. Junction temperature of a LED which is cooled with heatsink and liquid cooling block obtained in the experiment. 23°C is used both in the simulation and the experiment phase. Liquid cooling block material is choosed aluminium (Al) and polyamide. All tests and simulation are performed with three different flow rate. Temperature distribution of the designed product is investigated by doing the numerical simulations with a commercially software. In the simulations, fluid flow is assumed to be steady, incompressible and laminar and 3 dimensional (3D) Navier-Stokes equations are used. According to the calculations it is obtained that junction temperature is higher in the heatsink design compared to block cooled one. By changing the block material, it is desired to investigate the variation on the LED junction temperature. It is found that more efficient cooling can be obtained in block cooling by using less volume and weight. With block cooling lifetime of LED can be increased and flux loss can be decreased with the result of decreased junction temperature.

First-Principles Design of Novel Catalytic and Chemoresponsive Materials

NASA Astrophysics Data System (ADS)

Roling, Luke T.

An emerging trend in materials design is the use of computational chemistry tools to accelerate materials discovery and implementation. In particular, the parallel nature of computational models enables high-throughput screening approaches that would be laborious and time-consuming with experiments alone, and can be useful for identifying promising candidate materials for experimental synthesis and evaluation. Additionally, atomic-scale modeling allows researchers to obtain a detailed understanding of phenomena invisible to many current experimental techniques. In this thesis, we highlight mechanistic studies and successes in catalyst design for heterogeneous electrochemical reactions, discussing both anode and cathode chemistries. In particular, we evaluate the properties of a new class of Pd-Pt core-shell and hollow nanocatalysts toward the oxygen reduction reaction. We do not limit our study to electrochemical reactivity, but also consider these catalysts in a broader context by performing in-depth studies of their stability at elevated temperatures as well as investigating the mechanisms by which they are able to form. We also present fundamental surface science studies, investigating graphene formation and H2 dissociation, which are processes of both fundamental and practical interest in many catalytic applications. Finally, we extend our materials design paradigm outside the field of catalysis to develop and apply a model for the detection of small chemical analytes by chemoresponsive liquid crystals, and offer several predictions for improving the detection of small chemicals. A close connection between computation, synthesis, and experimental evaluation is essential to the work described herein, as computations are used to gain fundamental insight into experimental observations, and experiments and synthesis are in turn used to validate predictions of material activities from computational models.

Chemical Analysis for Chitin as a Measure of Fungal Infiltration of Cellulosic Materials.

DTIC Science & Technology

1976-12-01

the addition of 50 n’.illiliters of I 2N hydrochloric acid). Store at .~lO0 C. (11) Bushnell-Haas medium (12) Glucosamine hydrochloride (I milliliter...Infiltration Cellu!.jsic Materials Fungus-Induced Deterioration Glucosamine A TRACT (Cl~ i~s ,.v.ra. ia. ~V ~~~~~a . y d Sd.niIl ~ By block ni b.,) A chemical...EXPERIMENTAL PROCEDURE 3. Approach to the Problem. Carry out laboratory experiments to investigate variables as: shelf life of stock glucosamine , digestion

Lunar surface engineering properties experiment definition

NASA Technical Reports Server (NTRS)

Mitchell, J. K.; Goodman, R. E.; Hurlbut, F. C.; Houston, W. N.; Willis, D. R.; Witherspoon, P. A.; Hovland, H. J.

1971-01-01

Research on the mechanics of lunar soils and on developing probes to determine the properties of lunar surface materials is summarized. The areas of investigation include the following: soil simulation, soil property determination using an impact penetrometer, soil stabilization using urethane foam or phenolic resin, effects of rolling boulders down lunar slopes, design of borehole jack and its use in determining failure mechanisms and properties of rocks, and development of a permeability probe for measuring fluid flow through porous lunar surface materials.

Complex Study of the Physical Properties of Reticulated Vitreous Carbon

NASA Astrophysics Data System (ADS)

Alifanov, O. M.; Cherepanov, V. V.; Morzhukhina, A. V.

2015-01-01

We give an example of using a two-level identifi cation system incorporating an augmented mathematical model covering the structure, the thermal, electrophysical, and optical properties of nonmetallic ultraporous reticulated materials. The model, when combined with a nonstationary thermal experiment and methods of the theory of inverse heat transfer problems, permits determining the little studied characteristics of the above materials. We present some of the results of investigations of reticulated vitreous carbon confirming the possibility of using it in a number of engineering applications.

A study of the photocatalytic effects of aqueous suspensions of platinized semiconductor materials on the reaction rates of candidate redox reactions

NASA Technical Reports Server (NTRS)

Miles, A. M.

1982-01-01

The effectiveness of powdered semiconductor materials in photocatalyzing candidate redox reactions was investigated. The rate of the photocatalyzed oxidation of cyanide at platinized TiO2 was studied. The extent of the cyanide reaction was followed directly using an electroanalytical method (i.e. differential pulse polarography). Experiments were performed in natural or artificial light. A comparison was made of kinetic data obtained for photocatalysis at platinized powders with rate data for nonplatinized powders.

Impacts into quartz sand: Crater formation, shock metamorphism, and ejecta distribution in laboratory experiments and numerical models

NASA Astrophysics Data System (ADS)

Wünnemann, Kai; Zhu, Meng-Hua; Stöffler, Dieter

2016-10-01

We investigated the ejection mechanics by a complementary approach of cratering experiments, including the microscopic analysis of material sampled from these experiments, and 2-D numerical modeling of vertical impacts. The study is based on cratering experiments in quartz sand targets performed at the NASA Ames Vertical Gun Range. In these experiments, the preimpact location in the target and the final position of ejecta was determined by using color-coded sand and a catcher system for the ejecta. The results were compared with numerical simulations of the cratering and ejection process to validate the iSALE shock physics code. In turn the models provide further details on the ejection velocities and angles. We quantify the general assumption that ejecta thickness decreases with distance according to a power-law and that the relative proportion of shocked material in the ejecta increase with distance. We distinguish three types of shock metamorphic particles (1) melt particles, (2) shock lithified aggregates, and (3) shock-comminuted grains. The agreement between experiment and model was excellent, which provides confidence that the models can predict ejection angles, velocities, and the degree of shock loading of material expelled from a crater accurately if impact parameters such as impact velocity, impactor size, and gravity are varied beyond the experimental limitations. This study is relevant for a quantitative assessment of impact gardening on planetary surfaces and the evolution of regolith layers on atmosphereless bodies.

The Utility of Gas Gun Experiments in Developing Equations of State

NASA Astrophysics Data System (ADS)

Pittman, Emily; Hagelberg, Carl; Ramsey, Scott

2016-11-01

Gas gun experiments have the potential to investigate material properties in various well defined shock conditions, making them a valuable research tool for the development of equations of state (EOS) and material response under shock loading. Gas guns have the ability to create shocks for loading to pressures ranging from MPa to GPa. A variety of diagnostics techniques can be used to gather data from gas gun experiments; resulting data from these experiments is applicable to many fields of study. The focus of this set of experiments is the development of data on the Hugoniot for the overdriven products EOS of PBX 9501 to extend data from which current computational EOS models draw. This series of shots was conducted by M-9 using the two-stage gas-guns at LANL and aimed to gather data within the 30-120 GPa pressure regime. The experiment was replicated using FLAG, a Langrangian multiphysics code, using a one-dimensional setup which employs the Wescott Stewart Davis (WSD) reactive burn model. Prior to this series, data did not extend into this higher range, so the new data allowed for the model to be re-evaluated. A comparison of the results to the experimental data reveals that the model is a good fit to the data below 40 GPa. However, the model did not fall within the error bars for pressures above this region. This is an indication that the material models or burn model could be modified to better match the data.

KSC technician installs rows of experiment racks in IML-1 spacelab module

NASA Technical Reports Server (NTRS)

1991-01-01

Kennedy Space Center (KSC) technician installs rows of experiment racks in the International Microgravity Laboratory 1 (IML-1) in the KSC Operations and Checkout (O and C) Bldg. The IML-1 is scheduled to fly on STS-42 in early 1992, and will turn the shuttle into a laboratory dedicated to investigating the effects of microgravity on materials and life processes. View provided by KSC with alternate number KSC-91P-169.

ACE-1 experiment

NASA Image and Video Library

2013-06-24

ISS036-E-019760 (24 June 2013) --- In the International Space Station’s Destiny laboratory, NASA astronaut Karen Nyberg, Expedition 36 flight engineer, conducts a session with the Advanced Colloids Experiment (ACE)-1 sample preparation at the Light Microscopy Module (LMM) in the Fluids Integrated Rack / Fluids Combustion Facility (FIR/FCF). ACE-1 is a series of microscopic imaging investigations that uses the microgravity environment to examine flow characteristics and the evolution and ordering effects within a group of colloidal materials.

Dynamic Fracture Simulations of Explosively Loaded Cylinders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arthur, Carly W.; Goto, D. M.

2015-11-30

This report documents the modeling results of high explosive experiments investigating dynamic fracture of steel (AerMet® 100 alloy) cylinders. The experiments were conducted at Lawrence Livermore National Laboratory (LLNL) during 2007 to 2008 [10]. A principal objective of this study was to gain an understanding of dynamic material failure through the analysis of hydrodynamic computer code simulations. Two-dimensional and three-dimensional computational cylinder models were analyzed using the ALE3D multi-physics computer code.

Shear dilatancy and acoustic emission in dry and saturated granular materials

NASA Astrophysics Data System (ADS)

Brodsky, E. E.; Siman-Tov, S.

2017-12-01

Shearing of granular materials plays a strong role in naturally sheared systems as landslides and faults. Many works on granular flows have concentrated on dry materials, but relatively little work has been done on water saturated sands. Here we experimentally investigate dry versus saturated quartz-rich sand to understand the effect of the fluid medium on the rheology and acoustic waves emission of the sheared sand. The sand was sheared in a rotary shear rheometer under applied constant normal stress boundary at low (100 µm/s) to high (1 m/s) velocities. Mechanical, acoustic data and deformation were continuously recorded and imaged. For dry and water saturated experiments the granular volume remains constant for low shear velocities ( 10-3 m/s) and increases during shearing at higher velocities ( 1 m/s). Continuous imaging of the sheared sand show that the steady state shear band thickness is thicker during the high velocity steps. No significant change observed in the shear band thickness between dry and water saturated experiments. In contrast, the amount of dilation during water saturated experiments is about half the value measured for dry material. The measured decrease cannot be explained by shear band thickness change as such is not exist. However, the reduced dilation is supported by our acoustic measurements. In general, the event rate and acoustic event amplitudes increase with shear velocity. While isolated events are clearly detected during low velocities at higher the events overlap, resulting in a noisy signal. Although detection is better for saturated experiments, during the high velocity steps the acoustic energy measured from the signal is lower compared to that recorded for dry experiments. We suggest that the presence of fluid suppresses grain motion and particles impacts leading to mild increase in the internal pressure and therefore for the reduced dilation. In addition, the viscosity of fluids may influence the internal pressure via hydrodynamic lubrication which increases the fluid pressure and therefore increases the dilation compared to dry material. The effect is particularly strong for high viscosity fluids, as observed in the silicon oil experiment. Therefore, fluid viscosity can play a crucial role in determining the physics that controls the rheology of the sheared material.

Dislocations in bilayer graphene

NASA Astrophysics Data System (ADS)

Butz, Benjamin; Dolle, Christian; Niekiel, Florian; Weber, Konstantin; Waldmann, Daniel; Weber, Heiko B.; Meyer, Bernd; Spiecker, Erdmann

2014-01-01

Dislocations represent one of the most fascinating and fundamental concepts in materials science. Most importantly, dislocations are the main carriers of plastic deformation in crystalline materials. Furthermore, they can strongly affect the local electronic and optical properties of semiconductors and ionic crystals. In materials with small dimensions, they experience extensive image forces, which attract them to the surface to release strain energy. However, in layered crystals such as graphite, dislocation movement is mainly restricted to the basal plane. Thus, the dislocations cannot escape, enabling their confinement in crystals as thin as only two monolayers. To explore the nature of dislocations under such extreme boundary conditions, the material of choice is bilayer graphene, the thinnest possible quasi-two-dimensional crystal in which such linear defects can be confined. Homogeneous and robust graphene membranes derived from high-quality epitaxial graphene on silicon carbide provide an ideal platform for their investigation. Here we report the direct observation of basal-plane dislocations in freestanding bilayer graphene using transmission electron microscopy and their detailed investigation by diffraction contrast analysis and atomistic simulations. Our investigation reveals two striking size effects. First, the absence of stacking-fault energy, a unique property of bilayer graphene, leads to a characteristic dislocation pattern that corresponds to an alternating ABAC change of the stacking order. Second, our experiments in combination with atomistic simulations reveal a pronounced buckling of the bilayer graphene membrane that results directly from accommodation of strain. In fact, the buckling changes the strain state of the bilayer graphene and is of key importance for its electronic properties. Our findings will contribute to the understanding of dislocations and of their role in the structural, mechanical and electronic properties of bilayer and few-layer graphene.

Dislocations in bilayer graphene.

PubMed

Butz, Benjamin; Dolle, Christian; Niekiel, Florian; Weber, Konstantin; Waldmann, Daniel; Weber, Heiko B; Meyer, Bernd; Spiecker, Erdmann

2014-01-23

Dislocations represent one of the most fascinating and fundamental concepts in materials science. Most importantly, dislocations are the main carriers of plastic deformation in crystalline materials. Furthermore, they can strongly affect the local electronic and optical properties of semiconductors and ionic crystals. In materials with small dimensions, they experience extensive image forces, which attract them to the surface to release strain energy. However, in layered crystals such as graphite, dislocation movement is mainly restricted to the basal plane. Thus, the dislocations cannot escape, enabling their confinement in crystals as thin as only two monolayers. To explore the nature of dislocations under such extreme boundary conditions, the material of choice is bilayer graphene, the thinnest possible quasi-two-dimensional crystal in which such linear defects can be confined. Homogeneous and robust graphene membranes derived from high-quality epitaxial graphene on silicon carbide provide an ideal platform for their investigation. Here we report the direct observation of basal-plane dislocations in freestanding bilayer graphene using transmission electron microscopy and their detailed investigation by diffraction contrast analysis and atomistic simulations. Our investigation reveals two striking size effects. First, the absence of stacking-fault energy, a unique property of bilayer graphene, leads to a characteristic dislocation pattern that corresponds to an alternating AB B[Symbol: see text]AC change of the stacking order. Second, our experiments in combination with atomistic simulations reveal a pronounced buckling of the bilayer graphene membrane that results directly from accommodation of strain. In fact, the buckling changes the strain state of the bilayer graphene and is of key importance for its electronic properties. Our findings will contribute to the understanding of dislocations and of their role in the structural, mechanical and electronic properties of bilayer and few-layer graphene.

LIBS spectra of multi-component Al, Fe, Cu alloys and composite materials used for selected elements of armament and munition

NASA Astrophysics Data System (ADS)

Ostrowski, R.; Skrzeczanowski, W.; Rycyk, A.; CzyŻ, K.; Sarzyński, A.; Strzelec, M.; Jach, K.; Świerczyński, R.

2017-10-01

Spectral investigations in the UV-VIS range of selected Al, Cu, and Fe alloys and composite materials were performed using LIBS technique. The investigated objects were typical rifle cartridges, mortars, rocket launchers and samples of different type steel, Cu and Al alloys, as well as composite materials of special chemical composition. Two Nd:YAG lasers were applied: a short 4 ns, 60 mJ Brio Quantel/BigSky laser (1064 nm) and a long pulse 200/400 (up to 1000) µs ({ 2/4 up to 10 J) laser (1064 nm) constructed at the Institute of Optoelectronics MUT. This spectrochemical analysis was possible for Al, Cu, and Fe alloys objects for both lasers, and in case of composites only if the samples were irradiated by short laser pulse since in the experiment with the long pulse, all composite materials spectra, in general, were very similar to each other - they imitated a grey/black body spectra. For metal alloys in experiments with a short laser pulse only atomic spectra were observed while for long microsecond laser pulses molecular transitions have been registered for Al alloys. Electron temperatures of plasma created on different materials for short and long laser pulses were found on the base of Boltzmann plots. Temperatures are clearly higher for plasmas generated with a short laser pulse which results from much higher laser power density on the sample surface for short pulse and not from fluence which is 20-40 times larger for long pulse.

Vibronic Coupling Investigation to Compute Phosphorescence Spectra of Pt(II) Complexes.

PubMed

Vazart, Fanny; Latouche, Camille; Bloino, Julien; Barone, Vincenzo

2015-06-01

The present paper reports a comprehensive quantum mechanical investigation on the luminescence properties of several mono- and dinuclear platinum(II) complexes. The electronic structures and geometric parameters are briefly analyzed together with the absorption bands of all complexes. In all cases agreement with experiment is remarkable. Next, emission (phosphorescence) spectra from the first triplet states have been investigated by comparing different computational approaches and taking into account also vibronic effects. Once again, agreement with experiment is good, especially using unrestricted electronic computations coupled to vibronic contributions. Together with the intrinsic interest of the results, the robustness and generality of the approach open the opportunity for computationally oriented chemists to provide accurate results for the screening of large targets which could be of interest in molecular materials design.

Ground-based simulation of LEO environment: Investigations of a select LDEF material: FEP Teflon (trademark)

NASA Technical Reports Server (NTRS)

Cross, Jon B.; Koontz, Steven L.

1993-01-01

The Long Duration Exposure Facility (LDEF) has produced a wealth of data on materials degradation in the low earth orbit (LEO) space environment and has conclusively shown that surface chemistry (as opposed to surface physics-sputtering) is the key to understanding and predicting the degradation of materials in the LEO environment. It is also clear that materials degradation and spacecraft contamination are closely linked and that the fundamental mechanisms responsible for this linking are in general not well understood especially in the area of synergistic effects. The study of the fundamental mechanisms underlying materials degradation in LEO is hampered by the fact that the degradation process itself is not observed during the actual exposure to the environment. Rather the aftermath of the degradation process is studied, i.e., the material that remains after exposure is observed and mechanisms are proposed to explain the observed results. The EOIM-3 flight experiment is an attempt to bring sophisticated diagnostic equipment into the space environment and monitor the degradation process in real time through the use of mass spectrometry. More experiments of this nature which would include surface sensitive diagnostics (Auger and photoelectron spectroscopes) are needed to truly unravel the basic chemical mechanisms involved in the materials degradation process. Since these in-space capabilities will most likely not be available in the near future, ground-based LEO simulation facilities employing sophisticated diagnostics are needed to further advance the basic understanding of the materials degradation mechanisms. The LEO simulation facility developed at Los Alamos National Laboratory has been used to investigate the atomic oxygen/vacuum ultraviolet (AO/VUV) enhanced degradation of FEP Teflon. The results show that photo-ejection of polymer fragments occur at elevated temperature (200 C), that VUV synergistic rare gas sputtering of polymer fragments occur even at 25 C, and that combined OA/VUV interaction produces a wide variety of gas phase reaction products.

Post flight system analysis of FRECOPA (AO 138)

NASA Technical Reports Server (NTRS)

Durin, Christian

1991-01-01

The unexpected duration for the flight of the Long Duration Exposure Facility (LDEF) conducted CNES to create a special investigation group in order to analyze all the materials and systems which compose the French Cooperative Payload (FRECOPA) except the experiments especially prepared for the flight. The FRECOPA tray was on the trailing face (V-) of the LDEF and protected from the atomic oxygen flux during all the flight. However, the solar irradiation was very important with solar flux quite perpendicular to the experiment once an orbit. There was also a good vacuum environment. The objectives are to test the effects of the combined space environment on materials and components like: structure, thermal control coatings and blankets, electronic unit, motors, and mechanical fixtures. When the LDEF returned to Kennedy Space Center, a visual inspection showed the very good behavior of the materials used and it was noted that the three mechanisms to open and close the experiment canisters worked completely. Many impacts of micrometeoroids or space debris on the structure and on the thermal protections were observed. After FRECOPA was brought back to Toulouse, many tests were performed and include: working order tests, mechanical tests (tension), optical and electronic microscopy (SEM), surface analysis (ESCA, SIMS, RBS, AUGER, etc.), thermal analysis, pressure measurements, and gas analysis (outgassing tests). The results of these experiments are discussed.

Experimental investigations on thermo mechanical behaviour of aluminium alloys subjected to tensile loading and laser irradiation

NASA Astrophysics Data System (ADS)

Jelani, Mohsan; Li, Zewen; Shen, Zhonghua; Sardar, Maryam; Tabassum, Aasma

2017-05-01

The present work reports the investigation of the thermal and mechanical behaviour of aluminium alloys under the combined action of tensile loading and laser irradiations. The two types of aluminium alloys (Al-1060 and Al-6061) are used for the experiments. The continuous wave Ytterbium fibre laser (wavelength 1080 nm) was employed as irradiation source, while tensile loading was provided by tensile testing machine. The effects of various pre-loading and laser power densities on the failure time, temperature distribution and on deformation behaviour of aluminium alloys are analysed. The experimental results represents the significant reduction in failure time and temperature for higher laser powers and for high load values, which implies that preloading may contribute a significant role in the failure of the material at elevated temperature. The reason and characterization of material failure by tensile and laser loading are explored in detail. A comparative behaviour of under tested materials is also investigated. This work suggests that, studies considering only combined loading are not enough to fully understand the mechanical behaviour of under tested materials. For complete characterization, one must consider the effect of heating as well as loading rate.

Comparing field investigations with laboratory models to predict landfill leachate emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fellner, Johann; Doeberl, Gernot; Allgaier, Gerhard

2009-06-15

Investigations into laboratory reactors and landfills are used for simulating and predicting emissions from municipal solid waste landfills. We examined water flow and solute transport through the same waste body for different volumetric scales (laboratory experiment: 0.08 m{sup 3}, landfill: 80,000 m{sup 3}), and assessed the differences in water flow and leachate emissions of chloride, total organic carbon and Kjeldahl nitrogen. The results indicate that, due to preferential pathways, the flow of water in field-scale landfills is less uniform than in laboratory reactors. Based on tracer experiments, it can be discerned that in laboratory-scale experiments around 40% of pore watermore » participates in advective solute transport, whereas this fraction amounts to less than 0.2% in the investigated full-scale landfill. Consequences of the difference in water flow and moisture distribution are: (1) leachate emissions from full-scale landfills decrease faster than predicted by laboratory experiments, and (2) the stock of materials remaining in the landfill body, and thus the long-term emission potential, is likely to be underestimated by laboratory landfill simulations.« less

Experimental quantification of solute transport through the vadose zone under dynamic boundary conditions with dye tracers and optical methods.

NASA Astrophysics Data System (ADS)

Cremer, Clemens; Neuweiler, Insa

2017-04-01

Knowledge of subsurface solute transport processes is vital to investigate e.g. groundwater contamination, nutrient uptake by plant roots and to implement remediation strategies. Beside field measurements and numerical simulations, physical laboratory experiments represent a way to establish process understanding and furthermore validate numerical schemes. Atmospheric forcings, such as erratically varying infiltration and evaporation cycles, subject the shallow subsurface to local and temporal variations in water content and associated hydraulic conductivity of the prevailing porous media. Those variations in material properties can cause flow paths to differ between upward and downward flow periods. Thereby, the unsaturated subsurface presents a highly complicated, dynamic system. Following an extensive systematical numerical investigation of flow and transport through bimodal, unsaturated porous media under dynamic boundary conditions (Cremer et al., 2016), we conduct physical laboratory experiments in a 22 cm x 8 cm x 1 cm flow cell where we introduce structural heterogeneity in the form sharp material interfaces between different porous media. In all experiments, a constant pressure head is implemented at the lower boundary, while cyclic infiltration-evaporation phases are applied at the soil surface. As a reference case a stationary infiltration with a rate corresponding to the cycle-averaged infiltration rate is applied. By initial application of dye tracers, solute transport within the domain is visualized such that transport paths and redistribution processes can be observed in a qualitative manner. Solute leaching is quantified at the bottom outlet, where breakthrough curves are obtained via spectroscopy. Liquid and vapor flow in and out of the domain is obtained from multiple balances. Thereby, the interplay of material structural heterogeneity and alternating flow (transport) directions and flow (transport) paths is investigated. Results show lateral transport through the material interface which differs between the stationary (unilateral) and dynamic cases (bilateral). This qualitative observation is confirmed by breakthrough curves for dynamic experiments which generally show the trend of faster initial breakthrough and increased tailing when compared to stationary infiltration results. Literature Cremer, C.J.M., I. Neuweiler, M. Bechtold, J. Vanderborght (2016): Solute Transport in Heterogeneous Soil with Time-Dependent Boundary Conditions, Vadose Zone Journal 15 (6) DOI: 10.2136/vzj2015.11.0144

STEP Experiment Requirements

NASA Technical Reports Server (NTRS)

Brumfield, M. L. (Compiler)

1984-01-01

A plan to develop a space technology experiments platform (STEP) was examined. NASA Langley Research Center held a STEP Experiment Requirements Workshop on June 29 and 30 and July 1, 1983, at which experiment proposers were invited to present more detailed information on their experiment concept and requirements. A feasibility and preliminary definition study was conducted and the preliminary definition of STEP capabilities and experiment concepts and expected requirements for support services are presented. The preliminary definition of STEP capabilities based on detailed review of potential experiment requirements is investigated. Topics discussed include: Shuttle on-orbit dynamics; effects of the space environment on damping materials; erectable beam experiment; technology for development of very large solar array deployers; thermal energy management process experiment; photovoltaic concentrater pointing dynamics and plasma interactions; vibration isolation technology; flight tests of a synthetic aperture radar antenna with use of STEP.

Development and evaluation of elastomeric materials for geothermal applications

NASA Technical Reports Server (NTRS)

Mueller, W. A.; Kalfayan, S. H.; Reilly, W. W.; Ingham, J. D.

1978-01-01

A material for a casing packer for service for 24 hours in a geothermal environment was developed by synthesis of new elastomers and formulation of available materials. Formulation included use of commercial elastomer gumstocks and also crosslinking of plastic (high Tg) materials. Fibrous reinforcement of fluorocarbon rubbers was emphasized. Organic fiber reinforcement did not increase hot properties significantly. Glass fiber reinforcement gave significant increase in tensile properties. Elongation was reduced, and the glass-reinforced composition examined so far did not hold up well in the geothermal environment. Colloidal asbestos fibers were also investigated. A few experiments with polyphenyl ether gave material with low tensile and high compression set. Available high styrene SBR compositions were studied. Work to date suggests that new synthetic polymers will be required for service in geothermal environments.

The Efficacy of "Chunking" Reading Materials. Final Report.

ERIC Educational Resources Information Center

Carver, Ronald P.

In a series of three experiments involving 104 individuals, the effect of chunking sentences (the spatial separation of sentences into small groups of meaningfully related words) upon the reading rate and comprehension of mature readers was investigated. Passages and questions from a standardized reading test were displayed via an…

Developing Comprehension vs. Production of "Because" and "So."

ERIC Educational Resources Information Center

McCabe, Allyssa; Peterson, Carole

A series of studies evaluated methodological issues in the investigation of children's developing comprehension and production of the words "because" and "so." The familiarity of task materials and their relevance to 4-, 6-, and 8-year-old children's experience were the focus of the first study. For the second study, involving…

USE OF CATIONIC SURFACTANTS TO MODIFY SOIL SURFACES TO PROMOTE SORPTION AND RETARD MIGRATION OF HYDROPHOBIC ORGANIC COMPOUNDS

EPA Science Inventory

Cationic surfactants can be used to modify surfaces of soils and subsurface materials to promote adsorption of hydrophobic organic compounds (HOC). Batch and column experiments were performed to investigate this phenomenon with the cationic surfactant dodecylpyridinium (DP), a se...

The Encoding of Verbal Information. Final Report.

ERIC Educational Resources Information Center

Hopkins, Ronald H.

A research project involving 16 experiments investigated the nature of the encoding process for verbal materials, particularly differences arising from mode of presentation. The results showed that a change in mode of presentation of items produced a recovery from interference in short term retention. Since intermodal interference was lower than…

Disciplinary Literacy in Science: Developing Science Literacy through Trade Books

ERIC Educational Resources Information Center

Fang, Zhihui

2014-01-01

Developing science literacy requires not only firsthand explorations of the material world but also secondhand investigations with text. A potentially powerful kind of text in science is trade books. This column describes four classroom ploys for using science trade books to enhance students' secondhand experiences.

BEHAVIOR OF MEALWORMS, TEACHER'S GUIDE.

ERIC Educational Resources Information Center

Elementary Science Study, Newton, MA.

THIS TEACHER'S GUIDE IS DESIGNED FOR USE WITH AN ELEMENTARY SCIENCE STUDY UNIT, THE "BEHAVIOR OF MEALWORMS." BY MAKING CAREFUL OBSERVATIONS AND PERFORMING SIMPLE EXPERIMENTS, THE CHILDREN LEARN HOW TO APPROACH A PROBLEM, HOW TO INTERPRET AND EVALUATE DATA, AND, IN GENERAL, HOW TO CONDUCT A SCIENTIFIC INVESTIGATION. THE MATERIALS HAVE…

An Imagination Effect in Learning from Scientific Text

ERIC Educational Resources Information Center

Leopold, Claudia; Mayer, Richard E.

2015-01-01

Asking students to imagine the spatial arrangement of the elements in a scientific text constitutes a learning strategy intended to foster deep processing of the instructional material. Two experiments investigated the effects of mental imagery prompts on learning from scientific text. Students read a computer-based text on the human respiratory…

Gas Chromatographic Determination of Fatty Acid Compositions.

ERIC Educational Resources Information Center

Heinzen, Horacio; And Others

1985-01-01

Describes an experiment that: (1) has a derivation step using readily available reagents; (2) requires limited manipulative skills, centering attention on methodology; (3) can be completed within the time constraints of a normal laboratory period; and (4) investigates materials that are easy to acquire and are of great technical/biological…

Final Evaluation for the Neighborhood Educational Cultural Centerette.

ERIC Educational Resources Information Center

Frost, Patricia

Contained in this report is the final evaluation for the Neighborhood Educational Cultural Centerette Project. Objectives of the research project were to: (1) investigate, experiment with, create, and evaluate methods of instruction curriculum, and materials; analyze pupil learning styles and teacher-teaching styles; and to provide staff growth…

The Cost of Copyright Confusion for Media Literacy

ERIC Educational Resources Information Center

Hobbs, Renee; Jaszi, Peter; Aufderheide, Patricia

2007-01-01

Purpose: Media literacy educators in K-12, higher education, and after-school programs depend on the ability to make use of copyright materials (print, visual, film, video and online) in their teaching. This study investigated the knowledge, attitudes and experiences of media literacy educators regarding copyright and fair use. Methodology:…

Colonialism and Secondary Technical Education in Hong Kong: 1945-1997

ERIC Educational Resources Information Center

Lau, Wai Wah; Kan, Flora

2011-01-01

This study examines the influence of the colonial experience (1945-1997) on the planning of secondary technical education in Hong Kong. Specifically, the origins of secondary technical institutions and their positioning in secondary education are examined. Primary source materials are used as the basis of investigation and analysis, supplemented…

Why Does Military Combat Experience Adversely Affect Marital Relations?

ERIC Educational Resources Information Center

Gimbel, Cynthia; Booth, Alan

1994-01-01

Describes investigation of ways in which combat decreases marital quality and stability. Results support three models: (1) factors propelling men into combat also make them poor marriage material; (2) combat causes problems that increase marital adversity; and (3) combat intensifies premilitary stress and antisocial behavior which then negatively…

Space Shuttle Projects

NASA Image and Video Library

1984-04-01

The Long Duration Exposure Facility (LDEF) was designed by the Marshall Space Flight Center (MSFC) to test the performance of spacecraft materials, components, and systems that have been exposed to the environment of micrometeoroids and space debris for an extended period of time. The LDEF proved invaluable to the development of future spacecraft and the International Space Station (ISS). The LDEF carried 57 science and technology experiments, the work of more than 200 investigators. MSFC`s experiments included: Trapped Proton Energy Determination to determine protons trapped in the Earth's magnetic field and the impact of radiation particles; Linear Energy Transfer Spectrum Measurement Experiment which measures the linear energy transfer spectrum behind different shielding configurations; Atomic oxygen-Simulated Out-gassing, an experiment that exposes thermal control surfaces to atomic oxygen to measure the damaging out-gassed products; Thermal Control Surfaces Experiment to determine the effects of the near-Earth orbital environment and the shuttle induced environment on spacecraft thermal control surfaces; Transverse Flat-Plate Heat Pipe Experiment, to evaluate the zero-gravity performance of a number of transverse flat plate heat pipe modules and their ability to transport large quantities of heat; Solar Array Materials Passive LDEF Experiment to examine the effects of space on mechanical, electrical, and optical properties of lightweight solar array materials; and the Effects of Solar Radiation on Glasses. Launched aboard the Space Shuttle Orbiter Challenger's STS-41C mission April 6, 1984, the LDEF remained in orbit for five years until January 1990 when it was retrieved by the Space Shuttle Orbiter Columbia STS-32 mission and brought back to Earth for close examination and analysis.

Long Duration Exposure Facility (LDEF)

NASA Technical Reports Server (NTRS)

1984-01-01

The Long Duration Exposure Facility (LDEF) was designed by the Marshall Space Flight Center (MSFC) to test the performance of spacecraft materials, components, and systems that have been exposed to the environment of micrometeoroids and space debris for an extended period of time. The LDEF proved invaluable to the development of future spacecraft and the International Space Station (ISS). The LDEF carried 57 science and technology experiments, the work of more than 200 investigators. MSFC`s experiments included: Trapped Proton Energy Determination to determine protons trapped in the Earth's magnetic field and the impact of radiation particles; Linear Energy Transfer Spectrum Measurement Experiment which measures the linear energy transfer spectrum behind different shielding configurations; Atomic oxygen-Simulated Out-gassing, an experiment that exposes thermal control surfaces to atomic oxygen to measure the damaging out-gassed products; Thermal Control Surfaces Experiment to determine the effects of the near-Earth orbital environment and the shuttle induced environment on spacecraft thermal control surfaces; Transverse Flat-Plate Heat Pipe Experiment, to evaluate the zero-gravity performance of a number of transverse flat plate heat pipe modules and their ability to transport large quantities of heat; Solar Array Materials Passive LDEF Experiment to examine the effects of space on mechanical, electrical, and optical properties of lightweight solar array materials; and the Effects of Solar Radiation on Glasses. Launched aboard the Space Shuttle Orbiter Challenger's STS-41C mission April 6, 1984, the LDEF remained in orbit for five years until January 1990 when it was retrieved by the Space Shuttle Orbiter Columbia STS-32 mission and brought back to Earth for close examination and analysis.

EDRN Standard Operating Procedures (SOP) — EDRN Public Portal

Cancer.gov

The NCI’s Early Detection Research Network is developing a number of standard operating procedures for assays, methods, and protocols for collection and processing of biological samples, and other reference materials to assist investigators to conduct experiments in a consistent, reliable manner. These SOPs are established by the investigators of the Early Detection Research Network to maintain constancy throughout the Network. These SOPs represent neither a consensus, nor are the recommendations of NCI.

Mechanistic Studies of Combustion and Structure Formation During Synthesis of Advanced Materials

NASA Technical Reports Server (NTRS)

Varma, A.; Lau, C.; Mukasyan, A. S.

2001-01-01

Combustion in a variety of heterogeneous systems, leading to the synthesis of advanced materials, is characterized by high temperatures (2000-3500 K) and heating rates (up to 10(exp 6) K/s) at and ahead of the reaction front. These high temperatures generate liquids and gases which are subject to gravity-driven flow. The removal of such gravitational effects is likely to provide increased control of the reaction front, with a consequent improvement in control of the microstructure of the synthesized products. Thus, microgravity (mu-g) experiments lead to major advances in the understanding of fundamental aspects of combustion and structure formation under the extreme conditions of the combustion synthesis (CS) wave. In addition, the specific features of microgravity environment allow one to produce unique materials, which cannot be obtained under terrestrial conditions. The current research is a logic continuation of our previous work on investigations of the fundamental phenomena of combustion and structure formation that occur at the high temperatures achieved in a CS wave. Our research is being conducted in three main directions: 1) Microstructural Transformations during Combustion Synthesis of Metal-Ceramic Composites. The studies are devoted to the investigation of particle growth during CS of intermetallic-ceramic composites, synthesized from nickel, aluminum, titanium, and boron metal reactants. To determine the mechanisms of particle growth, the investigation varies the relative amount of components in the initial mixture to yield combustion wave products with different ratios of solid and liquid phases, under 1g and mu-g conditions; 2) Mechanisms of Heat Transfer during Reactions in Heterogeneous Media. Specifically, new phenomena of gasless combustion wave propagation in heterogeneous media with porosity higher than that achievable in normal gravity conditions, are being studied. Two types of mixtures are investigated: clad powders, where contact between reactants occurs within each particle, and mixtures of elemental powders, where interparticle contacts are important for the reaction; and 3) Mechanistic Studies of Phase Separation in Combustion of Thermite Systems. Studies are devoted to experiments on thermite systems (metal oxide-reducing metal) where phase separation processes occur to produce alloys with tailored compositions and properties. The separation may be either gravity-driven or due to surface forces, and systematic studies to elucidate the true mechanism are being conducted. The knowledge obtained will be used to find the most promising ways of controlling the microstructure and properties of combustion-synthesized materials. Low-gravity experiments are essential to create idealized an environment for insights into the physics and chemistry of advanced material synthesis processes.

Inorganic chemical investigation by X-ray fluorescence analysis - The Viking Mars Lander

NASA Technical Reports Server (NTRS)

Toulmin, P., III; Rose, H. J., Jr.; Baird, A. K.; Clark, B. C.; Keil, K.

1973-01-01

The inorganic chemical investigation experiment added in August 1972 to the Viking Lander scientific package uses an energy-dispersive X-ray fluorescence spectrometer in which four sealed, gas-filled proportional counters detect X-rays emitted from samples of the Martian surface materials irradiated by X-rays from radioisotope sources (Fe-55 and Cd-109). The instrument is inside the Lander body, and samples are to be delivered to it by the Viking Lander Surface Sampler. Instrument design is described along with details of the data processing and analysis procedures. The results of the investigation will characterize the surface materials of Mars as to elemental composition with accuracies ranging from a few tens of parts per million (at the trace-element level) to a few per cent (for major elements) depending on the element in question.

Atomic scale study of the life cycle of a dislocation in graphene from birth to annihilation

NASA Astrophysics Data System (ADS)

Lehtinen, O.; Kurasch, S.; Krasheninnikov, A. V.; Kaiser, U.

2013-06-01

Dislocations, one of the key entities in materials science, govern the properties of any crystalline material. Thus, understanding their life cycle, from creation to annihilation via motion and interaction with other dislocations, point defects and surfaces, is of fundamental importance. Unfortunately, atomic-scale investigations of dislocation evolution in a bulk object are well beyond the spatial and temporal resolution limits of current characterization techniques. Here we overcome the experimental limits by investigating the two-dimensional graphene in an aberration-corrected transmission electron microscope, exploiting the impinging energetic electrons both to image and stimulate atomic-scale morphological changes in the material. The resulting transformations are followed in situ, atom-by-atom, showing the full life cycle of a dislocation from birth to annihilation. Our experiments, combined with atomistic simulations, reveal the evolution of dislocations in two-dimensional systems to be governed by markedly long-ranging out-of-plane buckling.

Some limitations on processing materials in acoustic levitation devices

NASA Technical Reports Server (NTRS)

Oran, W. A.; Witherow, W. K.; Ross, B. B.; Rush, J. E.

1979-01-01

The spot heating of samples, suspended in an acoustic field, was investigated to determine if the technique could be used to process materials. A single axis resonance device operating in air at 25 C with an rms pressure maximum of 160 to 170 db was used in the experiments. The heat flow from a hot object suspended in a levitation node is dominated by the effects of the field, with the heat loss approximately 20 times larger than that due to natural convection. The acoustic forces which suspend the body at a node also serve to eject the heated air. The coupling between the locally heated region around the body and the acoustic field results in instabilities in both the pressure wave and force field. The investigations indicated the extreme difficulties in developing a materials processing device based on acoustic/spot heating for use in a terrestrial environment.

Femtosecond ablation of ultrahard materials

NASA Astrophysics Data System (ADS)

Dumitru, G.; Romano, V.; Weber, H. P.; Sentis, M.; Marine, W.

Several ultrahard materials and coatings of definite interest for tribological applications were tested with respect to their response when irradiated with fs laser pulses. Results on cemented tungsten carbide and on titanium carbonitride are reported for the first time and compared with outcomes of investigations on diamond and titanium nitride. The experiments were carried out in air, in a regime of 5-8 J/cm2 fluences, using the beam of a commercial Ti:sapphire laser. The changes induced in the surface morphology were analysed with a Nomarski optical microscope, and with SEM and AFM techniques. From the experimental data and from the calculated incident energy density distributions, the damage and ablation threshold values were determined. As expected, the diamond showed the highest threshold, while the cemented tungsten carbide exhibited typical values for metallic surfaces. The ablation rates determined (under the above-mentioned experimental conditions) were in the range 0.1-0.2 μm per pulse for all the materials investigated.

Effect of tool geometry and cutting parameters on delamination and thrust forces in drilling CFRP/Al-Li

NASA Astrophysics Data System (ADS)

El Bouami, Souhail; Habak, Malek; Franz, Gérald; Velasco, Raphaël; Vantomme, Pascal

2016-10-01

Composite materials are increasingly used for structural parts in the aeronautic industries. Carbon Fiber-Reinforced Plastics (CFRP) are often used in combination with metallic materials, mostly aluminium alloys. This raises new problems in aircraft assembly. Delamination is one of these problems. In this study, CFRP/Al-Li stacks is used as experimental material for investigation effect of interaction of cutting parameters (cutting speed and feed rate) and tool geometry on delamination and thrust forces in drilling operation. A plan of experiments, based on Taguchi design method, was employed to investigate the influence of tool geometry and in particular the point angle and cutting parameters on delamination and axial effort. The experimental results demonstrate that the feed rate is the major parameter and the importance of tool point angle in delamination and thrust forces in the stacks were shown.

Nanotexturing of surfaces to reduce melting point.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garcia, Ernest J.; Zubia, David; Mireles, Jose

2011-11-01

This investigation examined the use of nano-patterned structures on Silicon-on-Insulator (SOI) material to reduce the bulk material melting point (1414 C). It has been found that sharp-tipped and other similar structures have a propensity to move to the lower energy states of spherical structures and as a result exhibit lower melting points than the bulk material. Such a reduction of the melting point would offer a number of interesting opportunities for bonding in microsystems packaging applications. Nano patterning process capabilities were developed to create the required structures for the investigation. One of the technical challenges of the project was understandingmore » and creating the specialized conditions required to observe the melting and reshaping phenomena. Through systematic experimentation and review of the literature these conditions were determined and used to conduct phase change experiments. Melting temperatures as low as 1030 C were observed.« less

Frictional processes of bimaterial interfaces at seismic slip rates.

NASA Astrophysics Data System (ADS)

Passelegue, F. X.; Fabbri, O.; Leclère, H.; Spagnuolo, E.; Di Toro, G.

2017-12-01

Large subduction earthquakes ruptures propagate from crustal rock toward the sea floor along frictional interfaces of different lythologies. Up to now, frictional processes of rocks were mainly investigated along single material experimental faults. Here, we present the results of high velocity friction experiments coupled with high frequency acoustic monitoring system on biomaterial interfaces including gabbro, pyroxenite and serpentinized peridotite (>95%), following a recent field investigation highlighting bimaterial contacts in the Corsica ophiolitic nappe. We first studied the frictional processes of single materials which result in a mechanical behaviour comparable to previous studies. Both gabbro and pyroxenite exhibit two weakening stages. The first one corresponds to flash heating and the second stage occurs concomitantly with complete melting of the interface. In the case of serpentinite, only one weakening stage is observed, after a weakening slip distance of only few centimeters. We then conducted bimaterial experiments. The two couples tested were gabbro/pyroxenite and gabbro/serpentinite, as observed along natural fault zones (Corsica, France). In the case of gabbro/serpentinite, we observe that frictional processes are controlled by serpentinite. Mechanical curves replicate the behaviour of single serpentinite friction experiments. We observe that few melting occurs, and that the product of experiments consists in fine grained cataclasite, as observed in the field. The case of gabbro/pyroxenite is more complicated. The first weakening is controlled by the lithology of the sample installed on the static part of the rotary apparatus. However, the second weakening is controlled by the gabbro and mechanical curves are identical than those obtained in the case of single gabbro experiments. Supported by microstructural analysis and acoustic activity, our results suggest that frictional processes of bimaterial interfaces are controlled by the material presenting the lower weakening temperature. Finally, we show that bimaterial interfaces are expected to affect locally the rate of the stress transfer during large earthquakes, and induce accelerations or decelerations of the rupture front, explaining local emissions of high frequencies recorded during large ruptures.

Cometary Materials Originating from Interstellar Ices: Clues from Laboratory Experiments

NASA Astrophysics Data System (ADS)

Fresneau, A.; Abou Mrad, N.; d'Hendecourt, L. LS; Duvernay, F.; Flandinet, L.; Orthous-Daunay, F.-R.; Vuitton, V.; Thissen, R.; Chiavassa, T.; Danger, G.

2017-03-01

We use laboratory experiments to derive information on the chemistry occurring during the evolution of astrophysical ices from dense molecular clouds to interplanetary objects. Through a new strategy that consists of coupling very high resolution mass spectrometry and infrared spectroscopy (FT-IR), we investigate the molecular content of the organic residues synthesized from different initial ice compositions. We also obtain information on the evolution of the soluble part of the residues after their over-irradiation. The results give insight into the role of water ice as a trapping and diluting agent during the chemical evolution. They also give information about the importance of the amount of ammonia in such ices, particularly regarding its competition with the carbon chemistry. All of these results allow us to build a first mapping of the evolution of soluble organic matter based on its chemical and physical history. Furthermore, our results suggest that interstellar ices should lead to organic materials enriched in heteroatoms that present similarities with cometary materials but strongly differ from meteoritic organic material, especially in their C/N ratios.

PAMAM dendrimers and graphene: materials for removing aromatic contaminants from water.

PubMed

DeFever, Ryan S; Geitner, Nicholas K; Bhattacharya, Priyanka; Ding, Feng; Ke, Pu Chun; Sarupria, Sapna

2015-04-07

We present results from experiments and atomistic molecular dynamics simulations on the remediation of naphthalene by polyamidoamine (PAMAM) dendrimers and graphene oxide (GrO). Specifically, we investigate 3rd-6th generation (G3-G6) PAMAM dendrimers and GrO with different levels of oxidation. The work is motivated by the potential applications of these emerging nanomaterials in removing polycyclic aromatic hydrocarbon contaminants from water. Our experimental results indicate that GrO outperforms dendrimers in removing naphthalene from water. Molecular dynamics simulations suggest that the prominent factors driving naphthalene association to these seemingly disparate materials are similar. Interestingly, we find that cooperative interactions between the naphthalene molecules play a significant role in enhancing their association to the dendrimers and GrO. Our findings highlight that while selection of appropriate materials is important, the interactions between the contaminants themselves can also be important in governing the effectiveness of a given material. The combined use of experiments and molecular dynamics simulations allows us to comment on the possible factors resulting in better performance of GrO in removing polyaromatic contaminants from water.

Mechanics of Granular Materials Test Cell

NASA Technical Reports Server (NTRS)

1998-01-01

A test cell for Mechanics of Granular Materials (MGM) experiment is shown from all three sides by its video camera during STS-89. Sand and soil grains have faces that can cause friction as they roll and slide against each other, or even cause sticking and form small voids between grains. This complex behavior can cause soil to behave like a liquid under certain conditions such as earthquakes or when powders are handled in industrial processes. Mechanics of Granular Materials (MGM) experiments aboard the Space Shuttle use the microgravity of space to simulate this behavior under conditons that carnot be achieved in laboratory tests on Earth. MGM is shedding light on the behavior of fine-grain materials under low effective stresses. Applications include earthquake engineering, granular flow technologies (such as powder feed systems for pharmaceuticals and fertilizers), and terrestrial and planetary geology. Nine MGM specimens have flown on two Space Shuttle flights. Another three are scheduled to fly on STS-107. The principal investigator is Stein Sture of the University of Colorado at Boulder. Credit: NASA/Marshall Space Flight Center (MSFC)

Effects of bioturbation on environmental DNA migration through soil media

PubMed Central

2018-01-01

Extracting and identifying genetic material from environmental media (i.e. water and soil) presents a unique opportunity for researchers to assess biotic diversity and ecosystem health with increased speed and decreased cost as compared to traditional methods (e.g. trapping). The heterogeneity of soil mineralogy, spatial and temporal variations however present unique challenges to sampling and interpreting results. Specifically, fate/transport of genetic material in the terrestrial environment represents a substantial data gap. Here we investigate to what degree, benthic fauna transport genetic material through soil. Using the red worm (Eisenia fetida), we investigate how natural movement through artificial soil affect the transport of genetic material. All experiments were run in Frabill® Habitat® II worm systems with approximately 5 cm depth of artificial soil. We selected an “exotic” source of DNA not expected to be present in soil, zebrafish (Danio rerio) tissue. Experiment groups contained homogenized zebrafish tissue placed in a defined location combined with a varying number of worms (10, 30 or 50 worms per experimental group). Experimental groups comprised two controls and three treatment groups (representing different worm biomass) in triplicate. A total of 210 soil samples were randomly collected over the course of 15 days to investigate the degree of genetic transfer, and the rate of detection. Positive detections were identified in 14% - 38% of samples across treatment groups, with an overall detection rate of 25%. These findings highlight two important issues when utilizing environmental DNA for biologic assessments. First, benthic fauna are capable of redistributing genetic material through a soil matrix. Second, despite a defined sample container and abundance of worm biomass, as many as 86% of the samples were negative. This has substantial implications for researchers and managers who wish to interpret environmental DNA results from terrestrial systems. Studies such as these will aid in future study protocol design and sample collection methodology. PMID:29689092

Halogen lamp experiment, HALEX

NASA Technical Reports Server (NTRS)

Schmitt, G.; Stapelmann, J.

1986-01-01

The main purpose of the Halogen Lamp Experiment (HALEX) was to investigate the operation of a halogen lamp during an extended period in a microgravity environment and to prove its behavior in space. The Mirror Heating Facilities for Crystal Growth and Material Science Experiments in space relies on one or two halogen lamps as a furnace to melt the specimens. The HALEX aim is to verify: full power operation of a halogen lamp for a period of about 60 hours; achievement of about 10% of its terrestrial life span; and operation of the halogen lamp under conditions similar to furnace operation.

KSC-97PC1382

NASA Image and Video Library

1997-09-08

United States Microgravity Payload-4 (USMP-4) experiments are prepared to be flown on Space Shuttle mission STS-87 in the Space Station Processing Facility at Kennedy Space Center (KSC). This horizontal tube is known as MEPHISTO, the French acronym for a cooperative American-French investigation of the fundamentals of crystal growth. This experiment, designed for the study of solidification (or freezing) during the growth cycle of liquid materials used for semiconductor crystals, aims to aid in the development of techniques for growing higher quality crystals on Earth. All STS-87 experiments are scheduled for launch on Nov. 19 from KSC

Dynamic Triple-Mode Sorption and Outgassing in Materials.

PubMed

Sharma, Hom N; Harley, Stephen J; Sun, Yunwei; Glascoe, Elizabeth A

2017-06-07

Moisture uptake and outgassing can be detrimental to a system by altering the chemical and mechanical properties of materials within the system over time. In this work, we conducted isotherm experiments to investigate dynamic moisture sorption and desorption in markedly different materials, i.e., a polymeric material, Sylgard-184 and a ceramic aluminosilicate material, Zircar RS-1200, at different temperatures (30 °C-70 °C) by varying the water activity (0.0-0.90). Sylgard-184 showed a linear sorption and outgassing behavior with no-hysteresis over the entire temperature and water activity range considered here. Whereas, the sorption and outgassing of Zircar RS-1200 was highly non-linear with significant hysteresis, especially at higher water activities, at all temperatures considered here. The type of hysteresis suggested the presence of mesopores in Zircar RS-1200, whereas the lack of hysteresis in Sylgard-184 indicates that it has a nonporous structure. A diffusion model coupled with a dynamic, triple-mode sorption (Langmuir, Henry, and pooling modes) model employed in this study matched our experimental data very well and provides mechanistic insight into the processes. Our triple-mode sorption model was adaptive enough to (1) model these distinctly different materials and (2) predict sorption and outgassing under conditions that are distinctly different from the parameterization experiments.

Dynamic Triple-Mode Sorption and Outgassing in Materials

DOE PAGES

Sharma, Hom N.; Harley, Stephen J.; Sun, Yunwei; ...

2017-06-07

Moisture uptake and outgassing can be detrimental to a system by altering the chemical and mechanical properties of materials within the system over time. In this work, we conducted isotherm experiments to investigate dynamic moisture sorption and desorption in markedly different materials, i.e., a polymeric material, Sylgard-184 and a ceramic aluminosilicate material, Zircar RS-1200, at different temperatures (30 °C–70 °C) by varying the water activity (0.0–0.90). Sylgard-184 showed a linear sorption and outgassing behavior with no-hysteresis over the entire temperature and water activity range considered here. Whereas, the sorption and outgassing of Zircar RS-1200 was highly non-linear with significant hysteresis,more » especially at higher water activities, at all temperatures considered here. The type of hysteresis suggested the presence of mesopores in Zircar RS-1200, whereas the lack of hysteresis in Sylgard-184 indicates that it has a nonporous structure. A diffusion model coupled with a dynamic, triple-mode sorption (Langmuir, Henry, and pooling modes) model employed in this study matched our experimental data very well and provides mechanistic insight into the processes. Our triple-mode sorption model was adaptive enough to (1) model these distinctly different materials and (2) predict sorption and outgassing under conditions that are distinctly different from the parameterization experiments.« less

Sensitivity of corneal biomechanical and optical behavior to material parameters using design of experiments method.

PubMed

Xu, Mengchen; Lerner, Amy L; Funkenbusch, Paul D; Richhariya, Ashutosh; Yoon, Geunyoung

2018-02-01

The optical performance of the human cornea under intraocular pressure (IOP) is the result of complex material properties and their interactions. The measurement of the numerous material parameters that define this material behavior may be key in the refinement of patient-specific models. The goal of this study was to investigate the relative contribution of these parameters to the biomechanical and optical responses of human cornea predicted by a widely accepted anisotropic hyperelastic finite element model, with regional variations in the alignment of fibers. Design of experiments methods were used to quantify the relative importance of material properties including matrix stiffness, fiber stiffness, fiber nonlinearity and fiber dispersion under physiological IOP. Our sensitivity results showed that corneal apical displacement was influenced nearly evenly by matrix stiffness, fiber stiffness and nonlinearity. However, the variations in corneal optical aberrations (refractive power and spherical aberration) were primarily dependent on the value of the matrix stiffness. The optical aberrations predicted by variations in this material parameter were sufficiently large to predict clinically important changes in retinal image quality. Therefore, well-characterized individual variations in matrix stiffness could be critical in cornea modeling in order to reliably predict optical behavior under different IOPs or after corneal surgery.

Dynamic Triple-Mode Sorption and Outgassing in Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Hom N.; Harley, Stephen J.; Sun, Yunwei

Moisture uptake and outgassing can be detrimental to a system by altering the chemical and mechanical properties of materials within the system over time. In this work, we conducted isotherm experiments to investigate dynamic moisture sorption and desorption in markedly different materials, i.e., a polymeric material, Sylgard-184 and a ceramic aluminosilicate material, Zircar RS-1200, at different temperatures (30 °C–70 °C) by varying the water activity (0.0–0.90). Sylgard-184 showed a linear sorption and outgassing behavior with no-hysteresis over the entire temperature and water activity range considered here. Whereas, the sorption and outgassing of Zircar RS-1200 was highly non-linear with significant hysteresis,more » especially at higher water activities, at all temperatures considered here. The type of hysteresis suggested the presence of mesopores in Zircar RS-1200, whereas the lack of hysteresis in Sylgard-184 indicates that it has a nonporous structure. A diffusion model coupled with a dynamic, triple-mode sorption (Langmuir, Henry, and pooling modes) model employed in this study matched our experimental data very well and provides mechanistic insight into the processes. Our triple-mode sorption model was adaptive enough to (1) model these distinctly different materials and (2) predict sorption and outgassing under conditions that are distinctly different from the parameterization experiments.« less

Reduced and Oxidized Sulfur Compounds Detected by Evolved Gas Analyses of Materials from Yellowknife Bay, Gale Crater, Mars

NASA Technical Reports Server (NTRS)

McAdam, A. C.; Franz, H. B.; Archer, P. D., Jr.; Sutter, B.; Eigenbrode, J. L.; Freissinet, C.; Atreya, S. K.; Bish, D. L.; Blake, D. F.; Brunner, A.;

Safety Performance of Exterior Wall Insulation Material Based on Large Security Concept

NASA Astrophysics Data System (ADS)

Zuo, Q. L.; Wang, Y. J.; Li, J. S.

2018-05-01

In order to evaluate the fire spread characteristics of building insulation materials under corner fire, an experiment is carried out with small-scale fire spread test system. The change rule of the parameters such as the average height of the flame, the average temperature of the flame and the shape of the flame are analyzed. The variations of the fire spread characteristic parameters of the building insulation materials are investigated. The results show that the average temperature of Expanded Polystyrene (EPS) board, with different thickness, decrease - rise - decrease - increase. During the combustion process, the fire of 4cm thick plate spreads faster.

Sol-Gel Electrolytes Incorporated by Lanthanide Luminescent Materials and Their Photophysical Properties

NASA Astrophysics Data System (ADS)

Yu, Chufang; Zhang, Zhengyang; Fu, Meizhen; Gao, Jinwei; Zheng, Yuhui

2017-10-01

A group of silica gel electrolytes with lanthanide luminescent hybrid materials were assembled and investigated. Photophysical studies showed that terbium and europium hybrids displayed characteristic green and red emissions within the electrolytes. The influence of different concentration of the lanthanide hybrids on the electrochemical behavior of a gelled electrolyte valve-regulated lead-acid battery were studied through cyclic voltammograms, electrochemical impedance spectroscopy, water holding experiments and mobility tests. The morphology and particle size were analyzed by scanning electron microscopy. The results proved that lanthanide (Tb3+/Eu3+) luminescent materials are effective additives which will significantly improve the electrochemical properties of lead-acid batteries.

Spacecraft fire-safety experiments for space station: Technology development mission

NASA Technical Reports Server (NTRS)

Youngblood, Wallace W.

1988-01-01

Three concept designs for low-gravity, fire-safety related experiments are presented, as selected for the purpose of addressing key issues of enhancing safety and yet encouraging access to long-duration, manned spacecraft such as the NASA space station. The selected low-gravity experiments are the following: (1) an investigation of the flame-spread rate and combustion-product evolution of the burning of typical thicknesses of spacecraft materials in very low-speed flows; (2) an evaluation of the interaction of fires and candidate extinguishers in various fire scenarios; and (3) an investigation of the persistence and propagation of smoldering and deep-seated combustion. Each experiment is expected to provide fundamental combustion-science data, as well as the fire-safety applications, and each requires the unique long-duration, low-gravity environment of the space station. Two generic test facilities, i.e., the Combustion Tunnel Facility and the Combustion Facility, are proposed for space station accommodation to support the selected experiments. In addition, three near-term, fire-safety related experiments are described along with other related precursor activities.

Effect of Tritium on Cracking Threshold in 7075 Aluminum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duncan, A.; Morgan, M.

The effect of long-term exposure to tritium gas on the cracking threshold (K TH) of 7075 Aluminum Alloy was investigated. The alloy is the material of construction for a cell used to contain tritium in an accelerator at Jefferson Laboratory designed for inelastic scattering experiments on nucleons. The primary safety concerns for the Jefferson Laboratory tritium cell is a tritium leak due to mechanical failure of windows from hydrogen isotope embrittlement, radiation damage, or loss of target integrity from accidental excessive beam heating due to failure of the raster or grossly mis-steered beam. Experiments were conducted to investigate the potentialmore » for embrittlement of the 7075 Aluminum alloy from tritium gas.« less

Ceramic processing: Experimental design and optimization

NASA Technical Reports Server (NTRS)

Weiser, Martin W.; Lauben, David N.; Madrid, Philip

1992-01-01

The objectives of this paper are to: (1) gain insight into the processing of ceramics and how green processing can affect the properties of ceramics; (2) investigate the technique of slip casting; (3) learn how heat treatment and temperature contribute to density, strength, and effects of under and over firing to ceramic properties; (4) experience some of the problems inherent in testing brittle materials and learn about the statistical nature of the strength of ceramics; (5) investigate orthogonal arrays as tools to examine the effect of many experimental parameters using a minimum number of experiments; (6) recognize appropriate uses for clay based ceramics; and (7) measure several different properties important to ceramic use and optimize them for a given application.

Parahippocampal cortex is involved in material processing via echoes in blind echolocation experts.

PubMed

Milne, Jennifer L; Arnott, Stephen R; Kish, Daniel; Goodale, Melvyn A; Thaler, Lore

2015-04-01

Some blind humans use sound to navigate by emitting mouth-clicks and listening to the echoes that reflect from silent objects and surfaces in their surroundings. These echoes contain information about the size, shape, location, and material properties of objects. Here we present results from an fMRI experiment that investigated the neural activity underlying the processing of materials through echolocation. Three blind echolocation experts (as well as three blind and three sighted non-echolocating control participants) took part in the experiment. First, we made binaural sound recordings in the ears of each echolocator while he produced clicks in the presence of one of three different materials (fleece, synthetic foliage, or whiteboard), or while he made clicks in an empty room. During fMRI scanning these recordings were played back to participants. Remarkably, all participants were able to identify each of the three materials reliably, as well as the empty room. Furthermore, a whole brain analysis, in which we isolated the processing of just the reflected echoes, revealed a material-related increase in BOLD activation in a region of left parahippocampal cortex in the echolocating participants, but not in the blind or sighted control participants. Our results, in combination with previous findings about brain areas involved in material processing, are consistent with the idea that material processing by means of echolocation relies on a multi-modal material processing area in parahippocampal cortex. Copyright © 2014 Elsevier Ltd. All rights reserved.

Coarsening Experiment Being Prepared for Flight

NASA Technical Reports Server (NTRS)

Hickman, J. Mark

2001-01-01

The Coarsening in Solid-Liquid Mixtures-2 (CSLM-2) experiment is a materials science space flight experiment whose purpose is to investigate the kinetics of competitive particle growth within a liquid matrix. During coarsening, small particles shrink by losing atoms to larger particles, causing the larger particles to grow. In this experiment, solid particles of tin will grow (coarsen) within a liquid lead-tin eutectic matrix. The preceding figures show the coarsening of tin particles in a lead-tin eutectic as a function of time. By conducting this experiment in a microgravity environment, we can study a greater range of solid volume fractions, and the effects of sedimentation present in terrestrial experiments will be negligible. The CSLM-2 experiment is slated to fly onboard the International Space Station. The experiment will be run in the Microgravity Science Glovebox installed in the U.S. Laboratory module.

Rapid Prototyping for In Vitro Knee Rig Investigations of Prosthetized Knee Biomechanics: Comparison with Cobalt-Chromium Alloy Implant Material

PubMed Central

Schröder, Christian; Steinbrück, Arnd; Müller, Tatjana; Woiczinski, Matthias; Chevalier, Yan; Müller, Peter E.; Jansson, Volkmar

2015-01-01

Retropatellar complications after total knee arthroplasty (TKA) such as anterior knee pain and subluxations might be related to altered patellofemoral biomechanics, in particular to trochlear design and femorotibial joint positioning. A method was developed to test femorotibial and patellofemoral joint modifications separately with 3D-rapid prototyped components for in vitro tests, but material differences may further influence results. This pilot study aims at validating the use of prostheses made of photopolymerized rapid prototype material (RPM) by measuring the sliding friction with a ring-on-disc setup as well as knee kinematics and retropatellar pressure on a knee rig. Cobalt-chromium alloy (standard prosthesis material, SPM) prostheses served as validation standard. Friction coefficients between these materials and polytetrafluoroethylene (PTFE) were additionally tested as this latter material is commonly used to protect pressure sensors in experiments. No statistical differences were found between friction coefficients of both materials to PTFE. UHMWPE shows higher friction coefficient at low axial loads for RPM, a difference that disappears at higher load. No measurable statistical differences were found in knee kinematics and retropatellar pressure distribution. This suggests that using polymer prototypes may be a valid alternative to original components for in vitro TKA studies and future investigations on knee biomechanics. PMID:25879019

Interaction of 3H+ (as HTO) and 36Cl- (as Na36Cl) with crushed granite and corresponding fracture infill material investigated in column experiments.

PubMed

Štamberg, K; Palágyi, Š; Videnská, K; Havlová, V

The transport of 3 H + (as HTO) and 36 Cl - (as Na 36 Cl) was investigated in the dynamic system, i.e., in the columns filled with crushed pure granite and fracture infill of various grain sizes. The aim of column experiments was to determine important transport parameter, such as the retardation, respectively distribution coefficients, Peclet numbers and hydrodynamic dispersion coefficients. Furthermore, the research was focused to quantification of the effect of grain size on migration of studied radionuclides. The experimental breakthrough curves were fitted by a model based on the erfc-function, assuming a linear reversible equilibrium sorption/desorption isotherm, and the above mentioned transport parameters were determined. The results showed that influence of grain size on sorption of 3 H + and 36 Cl - was negligible. Retardation and distribution coefficients of both tracers converged to one and zero, respectively, in case of all fractions of crushed granite and infill material. Generally, the presumed ion exclusion of 36 Cl in anionic form was proved under given conditions, only very weak one seems to exist in a case of infill material. In principal, both radionuclides behaved as non-sorbing, conservative tracers. On the other hand, the influence of grain size on Peclet numbers value and on dispersion coefficient was observed for both crystalline materials, namely in agreement with theoretical suppositions that the values of Peclet numbers decrease with increasing grain size and values of dispersion coefficient increase.

Emission of biocides from treated materials: test procedures for water and air.

PubMed

Schoknecht, Ute; Wegner, Robby; Horn, Wolfgang; Jann, Oliver

2003-01-01

Methods for the determination of biocide emissions from treated materials into water and air were developed and tested in order to support a comparative ecological assessment of biocidal products. Leaching tests, experiments with simulated rain, extraction cleaning of carpets and emission chamber tests were performed with a series of treated materials. The experiments focused on the effect of changes in the procedure as well as characteristics of the specimens and demonstrate the suitability of the proposed methods for biocides of different product types. It was demonstrated that emissions of biocides into water can be compared on the basis of leaching tests in which the emission kinetics of the active ingredients are recorded. However, the water volume per surface area and the timetable for water changes have to be defined in such tests. Functions of flux rates related to time can be well described for inorganic compounds, whereas modelling of the data is more complicated for organic substances. Emission chamber tests using 20-litre and 23-litre glass exsiccators, originally developed to study volatile organic compounds, were successfully adapted for the investigation of the emission of biocides from treated materials which are usually semi volatile organic compounds. However test parameters and the method of analysis have to be adapted to the substances to be determined. Generally, it was found that the emission curves for the semi volatile organic compounds investigated differ from those of volatile organic compounds.

Laboratory Simulated Acid-Sulfate Weathering of Basaltic Materials: Implications for Formation of Sulfates at Meridiani Planum and Gusev Crater, Mars

NASA Technical Reports Server (NTRS)

Golden, D. C.; Ming, Douglas W.; Morris, Richard V.; Mertzman, A.

2006-01-01

Acid-sulfate weathering of basaltic materials is a candidate formation process for the sulfate-rich outcrops and rocks at the MER rover Opportunity and Spirit landing sites. To determine the style of acid-sulfate weathering on Mars, we weathered basaltic materials (olivine-rich glassy basaltic sand and plagioclase feldspar-rich basaltic tephra) in the laboratory under different oxidative, acid-sulfate conditions and characterized the alteration products. We investigated alteration by (1) sulfuric-acid vapor (acid fog), (2) three-step hydrothermal leaching treatment approximating an open system and (3) single-step hydrothermal batch treatment approximating a "closed system." In acid fog experiments, Al, Fe, and Ca sulfates and amorphous silica formed from plagioclase-rich tephra, and Mg and Ca sulfates and amorphous silica formed from the olivine-rich sands. In three-step leaching experiments, only amorphous Si formed from the plagioclase-rich basaltic tephra, and jarosite, Mg and Ca sulfates and amorphous silica formed from olivine-rich basaltic sand. Amorphous silica formed under single-step experiments for both starting materials. Based upon our experiments, jarosite formation in Meridiani outcrop is potential evidence for an open system acid-sulfate weathering regime. Waters rich in sulfuric acid percolated through basaltic sediment, dissolving basaltic phases (e.g., olivine) and forming jarosite, other sulfates, and iron oxides. Aqueous alteration of outcrops and rocks on the West Spur of the Columbia Hills may have occurred when vapors rich in SO2 from volcanic sources reacted with basaltic materials. Soluble ions from the host rock (e.g., olivine) reacted with S to form Ca-, Mg-, and other sulfates along with iron oxides and oxyhydroxides.

Recalcitrant Carbonaceous Material: A Source of Electron Donors for Anaerobic Microbial Metabolisms in the Subsurface?

NASA Astrophysics Data System (ADS)

Nixon, S. L.; Montgomery, W.; Sephton, M. A.; Cockell, C. S.

2014-12-01

More than 90% of organic material on Earth resides in sedimentary rocks in the form of kerogens; fossilized organic matter formed through selective preservation of high molecular weight biopolymers under anoxic conditions. Despite its prevalence in the subsurface, the extent to which this material supports microbial metabolisms is unknown. Whilst aerobic microorganisms are known to derive energy from kerogens within shales, utilization in anaerobic microbial metabolisms that proliferate in the terrestrial subsurface, such as microbial iron reduction, has yet to be demonstrated. Data are presented from microbial growth experiments in which kerogens and shales were supplied as the sole electron donor source for microbial iron reduction by an enrichment culture. Four well-characterized kerogens samples (representative of Types I-IV, classified by starting material), and two shale samples, were assessed. Organic analysis was carried out to investigate major compound classes present in each starting material. Parallel experiments were conducted to test inhibition of microbial iron reduction in the presence of each material when the culture was supplied with a full redox couple. The results demonstrate that iron-reducing microorganisms in this culture were unable to use kerogens and shales as a source of electron donors for energy acquisition, despite the presence of compound classes known to support this metabolism. Furthermore, the presence of these materials was found to inhibit microbial iron reduction to varying degrees, with some samples leading to complete inhibition. These results suggest that recalcitrant carbonaceous material in the terrestrial subsurface is not available for microbial iron reduction and similar metabolisms, such as sulphate-reduction. Further research is needed to investigate the inhibition exerted by these materials, and to assess whether these findings apply to other microbial consortia. These results may have significant implications for the role of anaerobic microbial metabolisms in the subsurface terrestrial carbon cycle. Kerogens are chemically similar to organic material in carbonaceous chondrites. As such, further study may provide insight into the potential availability of organic compounds for microbial metabolisms operating in the subsurface of Mars.

Anode energy transfer in a transient arc

NASA Astrophysics Data System (ADS)

Valensi, F.; Ratovoson, P.; Razafinimanana, M.; Gleizes, A.

2017-04-01

This work deals with experimental investigation of a transient arc. Arc configuration and electrode erosion were studied in order to quantify the energy transfer to the electrodes as a function of maximal current, time constant and electrodes material. Experiments with two consecutive arcs allow demonstrating non stationary behaviour of the arc electrode interaction. This is due to the fact that while the duration of the experiments is far larger than plasma phenomena time constants, it is comparable to those of electrode heating and melting processes.

Automated Space Processing Payloads Study. Volume 1: Executive Summary

NASA Technical Reports Server (NTRS)

1975-01-01

An investigation is described which examined the extent to which the experiment hardware and operational requirements can be met by automatic control and material handling devices; payload and system concepts are defined which make extensive use of automation technology. Topics covered include experiment requirements and hardware data, capabilities and characteristics of industrial automation equipment and controls, payload grouping, automated payload conceptual design, space processing payload preliminary design, automated space processing payloads for early shuttle missions, and cost and scheduling.

Investigation of Structure-Property Relationships in Systematic Series of Novel Polymers. [low frequency thermomechanical spectrometry of polymeric materials - computerized torsional braid experiments

NASA Technical Reports Server (NTRS)

Gillham, J. K.

1974-01-01

The results are discussed of the on-line interface of the Torsional Braid Analysis experiment to an Hierarchical Computer System for data acquisition, data reduction and control of experimental variables. Some experimental results are demonstrated and the data reduction procedures are outlined. Several modes of presentation of the final computer-reduced data are discussed in an attempt to elucidate possible interrelations between the thermal variation of the rigidity and loss parameters.

ACE-1 experiment

NASA Image and Video Library

2013-06-24

ISS036-E-019830 (24 June 2013) --- In the International Space Station’s Destiny laboratory, NASA astronaut Karen Nyberg, Expedition 36 flight engineer, speaks into a microphone while conducting a session with the Advanced Colloids Experiment (ACE)-1 sample preparation at the Light Microscopy Module (LMM) in the Fluids Integrated Rack / Fluids Combustion Facility (FIR/FCF). ACE-1 is a series of microscopic imaging investigations that uses the microgravity environment to examine flow characteristics and the evolution and ordering effects within a group of colloidal materials.

Technological parameters influence on the non-autoclaved foam concrete characteristics

NASA Astrophysics Data System (ADS)

Bartenjeva, Ekaterina; Mashkin, Nikolay

2017-01-01

Foam concretes are used as effective heat-insulating materials. The porous structure of foam concrete provides good insulating and strength properties that make them possible to be used as heat-insulating structural materials. Optimal structure of non-autoclaved foam concrete depends on both technological factors and properties of technical foam. In this connection, the possibility to manufacture heat-insulation structural foam concrete on a high-speed cavity plant with the usage of protein and synthetic foamers was estimated. This experiment was carried out using mathematical planning method, and in this case mathematical models were developed that demonstrated the dependence of operating performance of foam concrete on foaming and rotation speed of laboratory plant. The following material properties were selected for the investigation: average density, compressive strength, bending strength and thermal conductivity. The influence of laboratory equipment technological parameters on technical foam strength and foam stability coefficient in the cement paste was investigated, physical and mechanical properties of non-autoclaved foam concrete were defined based on investigated foam. As a result of investigation, foam concrete samples were developed with performance parameters ensuring their use in production. The mathematical data gathered demonstrated the dependence of foam concrete performance on the technological regime.

Numerical-experimental investigation of load paths in DP800 dual phase steel during Nakajima test

NASA Astrophysics Data System (ADS)

Bergs, Thomas; Nick, Matthias; Feuerhack, Andreas; Trauth, Daniel; Klocke, Fritz

2018-05-01

Fuel efficiency requirements demand lightweight construction of vehicle body parts. The usage of advanced high strength steels permits a reduction of sheet thickness while still maintaining the overall strength required for crash safety. However, damage, internal defects (voids, inclusions, micro fractures), microstructural defects (varying grain size distribution, precipitates on grain boundaries, anisotropy) and surface defects (micro fractures, grooves) act as a concentration point for stress and consequently as an initiation point for failure both during deep drawing and in service. Considering damage evolution in the design of car body deep drawing processes allows for a further reduction in material usage and therefore body weight. Preliminary research has shown that a modification of load paths in forming processes can help mitigate the effects of damage on the material. This paper investigates the load paths in Nakajima tests of a DP800 dual phase steel to research damage in deep drawing processes. Investigation is done via a finite element model using experimentally validated material data for a DP800 dual phase steel. Numerical simulation allows for the investigation of load paths with respect to stress states, strain rates and temperature evolution, which cannot be easily observed in physical experiments. Stress triaxiality and the Lode parameter are used to describe the stress states. Their evolution during the Nakajima tests serves as an indicator for damage evolution. The large variety of sheet metal forming specific load paths in Nakajima tests allows a comprehensive evaluation of damage for deep drawing. The results of the numerical simulation conducted in this project and further physical experiments will later be used to calibrate a damage model for simulation of deep drawing processes.

Zirconia-hydroxyapatite composite material with micro porous structure.

PubMed

Matsumoto, Takuya Junior; An, Sang-Hyun; Ishimoto, Takuya; Nakano, Takayoshi; Matsumoto, Takuya; Imazato, Satoshi

2011-11-01

Titanium plates and apatite blocks are commonly used for restoring large osseous defects in dental and orthopedic surgery. However, several cases of allergies against titanium have been recently reported. Also, sintered apatite block does not possess sufficient mechanical strength. In this study, we attempted to fabricate a composite material that has mechanical properties similar to biocortical bone and high bioaffinity by compounding hydroxyapatite (HAp) with the base material zirconia (ZrO(2)), which possesses high mechanical properties and low toxicity toward living organisms. After mixing the raw material powders at several different ZrO(2)/HAp mixing ratios, the material was compressed in a metal mold (8 mm in diameter) at 5 MPa. Subsequently, it was sintered for 5 h at 1500°C to obtain the ZrO(2)/HAp composite. The mechanical property and biocompatibility of materials were investigated. Furthermore, osteoconductivity of materials was investigated by animal studies. A composite material with a minute porous structure was successfully created using ZrO(2)/HAp powders, having different particle sizes, as the starting material. The material also showed high protein adsorption and a favorable cellular affinity. When the mixing ratio was ZrO(2)/HAp=70/30, the strength was equal to cortical bone. Furthermore, in vivo experiments confirmed its high osteoconductivity. The composite material had strength similar to biocortical bones with high cell and tissue affinities by compounding ZrO(2) and HAp. The ZrO(2)/HAp composite material having micro porous structure would be a promising bone restorative material. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Deontic reasoning with emotional content: evolutionary psychology or decision theory?

PubMed

Perham, Nick; Oaksford, Mike

2005-09-10

Three experiments investigated the contrasting predictions of the evolutionary and decision-theoretic approaches to deontic reasoning. Two experiments embedded a hazard management (HM) rule in a social contract scenario that should lead to competition between innate modules. A 3rd experiment used a pure HM task. Threatening material was also introduced into the antecedent, p, of a deontic rule, if p then must q. According to the evolutionary approach, more HM responses (Cosmides & Tooby, 2000) are predicted when p is threatening, whereas decision theory predicts fewer. All 3 experiments were consistent with decision theory. Other theories are discussed, and it is concluded that they cannot account for the behavior observed in these experiments. 2005 Lawrence Erlbaum Associates, Inc.

Experience and Reflection: Preservice Science Teachers' Capacity for Teaching Inquiry

NASA Astrophysics Data System (ADS)

Melville, Wayne; Fazio, Xavier; Bartley, Anthony; Jones, Doug

2008-10-01

In this article, we investigate the relationship between preservice teachers’ inquiry experience and their capacity to reflect on the challenges involved in implementing inquiry into classrooms. For data, we draw on the personal narratives of preservice science teachers enrolled in science instruction courses. Preservice teachers with extensive inquiry experiences perceive implementation challenges principally in terms of teaching and student learning. This contrasts with the perceptions of preservice teachers with limited inquiry experience for whom the main concerns relate to the negative perceptions of others, time, the curriculum, and materials. By identifying these perceptions, it may be possible to develop courses that assist limited and moderate-experience preservice teachers’ move toward the perceptions of their more inquiry experienced colleagues.

Theoretical and experimental study of organic nano-material for acetate anion based on 1, 10-phenanthroline.

PubMed

Shang, Xuefang; Zhao, Yuan; Wei, Xiaofang; Feng, Yaqian; Li, Xin; Gao, Shuyan; Xu, Xiufang

2015-01-01

New phenanthroline derivatives (1, 2, 3, 4) containing phenol groups have been synthesized and optimized. The nano-material of compound 2 was also developed. Their binding properties were evaluated for various biological anions (F(-), Cl(-), Br(-), I(-), AcO(-) and H(2)PO(4)(-)) by theoretical investigation, UV-vis, fluorescence, (1)HNMR titration experiments and these compounds all showed strong binding ability for AcO(-) without the interference of other anions tested. The anion binding ability could be regularized by electron push-pull properties of the ortho- or para- substituent on benzene. Theoretical investigation analysis revealed the effect of intramolecular hydrogen bond existed between -OH and other atoms in the structure of these compounds.

Space Product Development (SPD)

NASA Image and Video Library

2003-01-12

Experiments to seek solutions for a range of biomedical issues are at the heart of several investigations that will be hosted by the Commercial Instrumentation Technology Associates (ITA), Inc. Biomedical Experiments (CIBX-2) payload. CIBX-2 is unique, encompassing more than 20 separate experiments including cancer research, commercial experiments, and student hands-on experiments from 10 schools as part of ITA's ongoing University Among the Stars program. This drawing depicts a cross-section of a set of Dual-Materials Dispersion Apparatus (DMDA) specimen wells, one of which can include a reverse osmosis membrane to dewater a protein solution and thus cause crystallization. Depending on individual needs, two or three wells may be used, the membrane may be absent, or other proprietary enhancements may be present. The experiments are sponsored by NASA's Space Product Development Program (SPD).

The composition of category conjunctions.

PubMed

Hutter, Russell R C; Crisp, Richard J

2005-05-01

In three experiments, the authors investigated the impression formation process resulting from the perception of familiar or unfamiliar social category combinations. In Experiment 1, participants were asked to generate attributes associated with either a familiar or unfamiliar social category conjunction. Compared to familiar combinations, the authors found that when the conjunction was unfamiliar, participants formed their impression less from the individual constituent categories and relatively more from novel emergent attributes. In Experiment 2, the authors replicated this effect using alternative experimental materials. In Experiment 3, the effect generalized to additional (orthogonally combined) gender and occupation categories. The implications of these findings for understanding the processes involved in the conjunction of social categories, and the formation of new stereotypes, are discussed.