Arcjet Testing and Thermal Model Development for Multilayer Felt Reusable Surface Insulation
NASA Technical Reports Server (NTRS)
Milos, Frank S.; Scott, Carl Douglas; Papa, Steven V.
2012-01-01
Felt Reusable Surface Insulation was used extensively on leeward external surfaces of the Shuttle Orbiter, where the material is reusable for temperatures up to 670 K. For application on leeward surfaces of the Orion Multi-Purpose Crew Vehicle, where predicted temperatures reach 1620 K, the material functions as a pyrolyzing conformal ablator. An arcjet test series was conducted to assess the performance of multilayer Felt Reusable Surface Insulation at high temperatures, and a thermal-response, pyrolysis, and ablation model was developed. Model predictions compare favorably with the arcjet test data
NASA Technical Reports Server (NTRS)
Forgsberg, K.
1979-01-01
The primary insulation system used to protect the space shuttle orbiter on reentry is an externally attached, rigidized, fibrous silica which has been machined into tiles. The tiles constitute the temperature reusable surface insulation system and are used on over 70 percent of the vehicle exterior surface where peak temperatures range from 400 to 1260 C. Cargon-carbon leading edges are used in areas where peak temperatures exceed 1650 C and a felt flexible insulation is used in regions below 400 C. Approximately 32,000 tiles are used in the HRST system and because of vehicle configuration, aerodynamic requirements, and weight considerations no two tiles are alike. Fabrication and quality control procedures are described.
Tian, Jiangnan; Zhao, Jixiang; Olajuyin, Ayobami Matthew; Sharshar, Moustafa Mohamed; Mu, Tingzhen; Yang, Maohua; Xing, Jianmin
2016-08-01
Polytetrafluoroethylene/ferromagnetic nanoparticle/carbon black (PTFE/MNP/CB)-modified graphite felt (GF) was successfully applied as cathode for the mineralization of rhodamine B (RhB) in electro-Fenton (EF) process. The modified cathode showed high decolorization efficiency for RhB solution even in neutral pH condition and without external aeration, achieving nearly complete decolorization and 89.52 % total organic carbon (TOC) removal after 270-min oxidation with the MNP load 1.2 g at 50 A/m(2). Moreover, the operational parameters (current density, MNP load, initial pH, and airflow rate) were optimized. After that, adsorption isotherm was also conducted to compare the absorption quantity of CB and carbon nanotube (CNT). Then, the surface morphologies of MNPs were characterized by transmission electron microscope (TEM), energy-dispersive X-ray detector (EDX), and Fourier transform infrared spectroscopy (FTIR); and the modified cathode was characterized by SEM and contact angle. Finally, the stability and reusability of modified cathode were tested. Result uncovered that the PTFE/MNP/CB-modified cathode has the potential for industrial application and the solution after treatment was easily biodegradable.
Effect of chromia doping of thermal stability of silica fibers
NASA Technical Reports Server (NTRS)
Zaplatynsky, I.
1974-01-01
Commercial silica fibers of the type being evaluated for reusable surface insulation for reentry vehicles were found to be porous and composed of subfibers. The effect on shrinkage and devitrification of soaking such silica fibers in water, acetic acid, chromium acetate, and chromium nitrate solutions was studied. Felted specimens made of chromia-doped fibers shrunk only about one-half as much as those made of untreated fibers after exposure in air for 4 hours at 1300 C. The devitrification rate of fibers given prolonged soaks in chromium nitrate was as low as that of as-received fibers.
Evaluation of low cost/high temperature insulation, July 1974 - June 1975
NASA Technical Reports Server (NTRS)
Strauss, E. L.
1975-01-01
Six fiber products and six insulation blankets comprising silica, alumina, zirconia, mullite, and mixed ceramic systems were subjected to furnace exposures up to 500 hours at temperatures of 1000 to 1600 C and evaluated for chemical and dimensional stability and for changes in thermal conductivity. Alumina, zirconia, and mullite fibers were fabricated into reusable surface insulation (RSI) tile by water-felting and reimpregnation with ethyl silicate. Specimens were exposed to 25 thermal cycles at 1200 C and 1400 C and a pressure of 10 and 32 torr, respectively. Production costs for 930 sq m (10,000 sq ft) of blanket insulation and of alumina RSI tile were developed.
2012-04-05
CAPE CANAVERAL, Fla. – Kennedy Space Center Director Bob Cabana, right, shows a space shuttle felt reusable surface insulation FRSI blanket to Florida’s Lt. Gov. Jennifer Carroll during a tour of Kennedy’s Orbiter Processing Facility-1. The blanket is part of the shuttle’s thermal protection system which covers the shuttle’s exterior and protects it from the heat of re-entry. The tour coincided with Carroll’s visit to Kennedy for a meeting with Cabana. Atlantis is being prepared for public display at the Kennedy Space Center Visitor Complex in 2013. The groundbreaking for Atlantis’ exhibit hall took place in January Atlantis is scheduled to be moved to the visitor complex in November. For more information, visit http://www.nasa.gov/shuttle. Photo credit: NASA/Jim Grossmann
Orbital Debris Impact Damage to Reusable Launch Vehicles
NASA Technical Reports Server (NTRS)
Robinson, Jennifer H.
1998-01-01
In an effort by the National Aeronautics and Space Administration (NASA), hypervelocity impact tests were performed on thermal protection systems (TPS) applied on the external surfaces of reusable launch vehicles (RLV) to determine the potential damage from orbital debris impacts. Three TPS types were tested, bonded to composite structures representing RLV fuel tank walls. The three heat shield materials tested were Alumina-Enhanced Thermal Barrier-12 (AETB-12), Flexible Reusable Surface Insulation (FRSI), and Advanced Flexible Reusable Surface Insulation (AFRSI). Using this test data, predictor equations were developed for the entry hole diameters in the three TPS materials, with correlation coefficients ranging from 0.69 to 0.86. Possible methods are proposed for approximating damage occurring at expected orbital impact velocities higher than tested, with references to other published work.
Coatings and Surface Treatments for Reusable Entry Systems
NASA Technical Reports Server (NTRS)
Johnson, Sylvia M.
2016-01-01
This talk outlines work in coatings for TPS done at NASA Ames. coatings and surface treatments on reusable TPS are critical for controlling the behavior of the materials. coatings discussed include RCG, TUFI and HETC. TUFROc is also discussed.
NASA Astrophysics Data System (ADS)
Sabet Divsholi, Bahador; Yang, Yaowen
2011-04-01
Piezoelectric lead zirconate titanate (PZT) transducers have been used for health monitoring of various structures over the last two decades. There are three methods to install the PZT transducers to structures, namely, surface bonded, reusable setup and embedded PZTs. The embedded PZTs and reusable PZT setups can be used for concrete structures during construction. On the other hand, the surface bonded PZTs can be installed on the existing structures. In this study, the applicability and limitations of each installation method are experimentally studied. A real size concrete structure is cast, where the surface bonded, reusable setup and embedded PZTs are installed. Monitoring of concrete hydration and structural damage is conducted by the electromechanical impedance (EMI), wave propagation and wave transmission techniques. It is observed that embedded PZTs are suitable for monitoring the hydration of concrete by using both the EMI and the wave transmission techniques. For damage detection in concrete structures, the embedded PZTs can be employed using the wave transmission technique, but they are not suitable for the EMI technique. It is also found that the surface bonded PZTs are sensitive to damage when using both the EMI and wave propagation techniques. The reusable PZT setups are able to monitor the hydration of concrete. However they are less sensitive in damage detection in comparison to the surface bonded PZTs.
NASA Astrophysics Data System (ADS)
Nagihara, S.; Zacny, K.; Chu, P.; Kiefer, W. S.
2018-02-01
We propose to equip the Deep Space Gateway spacecraft with a reusable lander that can shuttle to and from the lunar surface, and use it for collecting heat flow measurements globally on the lunar surface.
Magnetically-refreshable receptor platform structures for reusable nano-biosensor chips
NASA Astrophysics Data System (ADS)
Yoo, Haneul; Lee, Dong Jun; Cho, Dong-guk; Park, Juhun; Nam, Ki Wan; Tak Cho, Young; Park, Jae Yeol; Chen, Xing; Hong, Seunghun
2016-01-01
We developed a magnetically-refreshable receptor platform structure which can be integrated with quite versatile nano-biosensor structures to build reusable nano-biosensor chips. This structure allows one to easily remove used receptor molecules from a biosensor surface and reuse the biosensor for repeated sensing operations. Using this structure, we demonstrated reusable immunofluorescence biosensors. Significantly, since our method allows one to place receptor molecules very close to a nano-biosensor surface, it can be utilized to build reusable carbon nanotube transistor-based biosensors which require receptor molecules within a Debye length from the sensor surface. Furthermore, we also show that a single sensor chip can be utilized to detect two different target molecules simply by replacing receptor molecules using our method. Since this method does not rely on any chemical reaction to refresh sensor chips, it can be utilized for versatile biosensor structures and virtually-general receptor molecular species.
Improvement of reusable surface insulation material
NASA Technical Reports Server (NTRS)
1972-01-01
The results are presented of a program to improve the reusable surface insulation (RSI) system through the improvement of the LI-1500 material properties and the simplification of the RSI system. The improvements made include: 2500 F-capability RSI systems, water-impervious surface coatings, establishment of a high-emittance coating constituent, development of a secondary water-reduction system, and achievement of a lower density (9 pcf) RSI material.
Development of design allowables data for adhesives for attaching reusable surface insulation
NASA Technical Reports Server (NTRS)
Owen, H. P.; Carroll, M. T.
1972-01-01
Results are presented from tests to establish design allowables data for the following room temperature vulcanizing (RTV) silicone rubber based adhesives: (1) General Electric's RTV-560; (2) Dow Corning's 93-046; and (3) Martin Marietta's SLA-561. These adhesives are being evaluated for attaching reusable surface insulation to space shuttle structure.
Ferrocene functionalized graphene based electrode for the electro-Fenton oxidation of ciprofloxacin.
Divyapriya, Govindaraj; Nambi, Indumathi; Senthilnathan, Jaganathan
2018-05-26
Ferrocene functionalized graphene based graphite felt electrode was firstly investigated for heterogeneous electro-Fenton oxidation of ciprofloxacin in neutral pH condition. Electrochemical reduction of Ferrocene functionalized graphene oxide (Fc-ErGO) was performed by cyclic voltammetry technique. At neutral pH condition, Fc-ErGO electrode (0.035 min ─1 ) exhibited ∼3 times and ∼9 times higher removal rates in comparison with plane ErGO (0.010 min ─1 ) and plane graphite felt (0.004 min ─1 ) electrodes respectively. The effect of pH and applied potential were studied for the degradation of ciprofloxacin in Fc-ErGO based electrode. Higher removal rate was observed at acidic pH (0.222 min ─1 ), whereas alkaline pH showed lower removal efficiency (0.014 min ─1 ). > 99% removal of ciprofloxacin was achieved with in 15 min and 120 min of reactions period at pH 3.0 and pH 7.0, respectively. H 2 O 2 generation was found to be high in plane ErGO electrode system in all of the pH conditions. Owing to the high redox ability of ferrocene, Fc-ErGO electrode generated high concentration of OH radicals (426 μM pH 3.0; 247 μM pH 7.0; 210 μM pH 9.0) than ErGO and plane graphite felt electrodes; The electrode reusability study was performed to understand the electrode stability. There was no significant change in removal efficiency even after the 5th cycle of reusability study at both acidic and neutral conditions. The possible mechanism of oxidation in Fc-ErGO based electro-Fenton process was also proposed based on the continuous monitoring of H 2 O 2 and OH radicals generated in the system. Copyright © 2018. Published by Elsevier Ltd.
Sound absorption of low-temperature reusable surface insulation candidate materials
NASA Technical Reports Server (NTRS)
Johnston, J. D.
1974-01-01
Sound absorption data from tests of four candidate low-temperature reusable surface insulation materials are presented. Limitations on the use of the data are discussed, conclusions concerning the effective absorption of the materials are drawn, and the relative significance to Vibration and Acoustic Test Facility test planning of the absorption of each material is assessed.
NASA Technical Reports Server (NTRS)
Banas, R. P.; Elgin, D. R.; Cordia, E. R.; Nickel, K. N.; Gzowski, E. R.; Aguiler, L.
1983-01-01
Three ceramic, reusable surface insulation materials and two borosilicate glass coatings were used in the fabrication of tiles for the Space Shuttle orbiters. Approximately 77,000 tiles were made from these materials for the first three orbiters, Columbia, Challenger, and Discovery. Lessons learned in the development, scale up to production and manufacturing phases of these materials will benefit future production of ceramic reusable surface insulation materials. Processing of raw materials into tile blanks and coating slurries; programming and machining of tiles using numerical controlled milling machines; preparing and spraying tiles with the two coatings; and controlling material shrinkage during the high temperature (2100-2275 F) coating glazing cycles are among the topics discussed.
Poorly processed reusable surface disinfection tissue dispensers may be a source of infection.
Kampf, Günter; Degenhardt, Stina; Lackner, Sibylle; Jesse, Katrin; von Baum, Heike; Ostermeyer, Christiane
2014-01-21
Reusable surface disinfectant tissue dispensers are used in hospitals in many countries because they allow immediate access to pre-soaked tissues for targeted surface decontamination. On the other hand disinfectant solutions with some active ingredients may get contaminated and cause outbreaks. We determined the frequency of contaminated surface disinfectant solutions in reusable dispensers and the ability of isolates to multiply in different formulations. Reusable tissue dispensers with different surface disinfectants were randomly collected from healthcare facilities. Solutions were investigated for bacterial contamination. The efficacy of two surface disinfectants was determined in suspension tests against two isolated species directly from a contaminated solution or after 5 passages without selection pressure in triplicate. Freshly prepared use solutions were contaminated to determine survival of isolates. 66 dispensers containing disinfectant solutions with surface-active ingredients were collected in 15 healthcare facilities. 28 dispensers from nine healthcare facilities were contaminated with approximately 107 cells per mL of Achromobacter species 3 (9 hospitals), Achromobacter xylosoxidans or Serratia marcescens (1 hospital each). In none of the hospitals dispenser processing had been adequately performed. Isolates regained susceptibility to the disinfectants after five passages without selection pressure but were still able to multiply in different formulations from different manufacturers at room temperature within 7 days. Neglecting adequate processing of surface disinfectant dispensers has contributed to frequent and heavy contamination of use-solutions based on surface active ingredients. Tissue dispenser processing should be taken seriously in clinical practice.
Poorly processed reusable surface disinfection tissue dispensers may be a source of infection
2014-01-01
Background Reusable surface disinfectant tissue dispensers are used in hospitals in many countries because they allow immediate access to pre-soaked tissues for targeted surface decontamination. On the other hand disinfectant solutions with some active ingredients may get contaminated and cause outbreaks. We determined the frequency of contaminated surface disinfectant solutions in reusable dispensers and the ability of isolates to multiply in different formulations. Methods Reusable tissue dispensers with different surface disinfectants were randomly collected from healthcare facilities. Solutions were investigated for bacterial contamination. The efficacy of two surface disinfectants was determined in suspension tests against two isolated species directly from a contaminated solution or after 5 passages without selection pressure in triplicate. Freshly prepared use solutions were contaminated to determine survival of isolates. Results 66 dispensers containing disinfectant solutions with surface-active ingredients were collected in 15 healthcare facilities. 28 dispensers from nine healthcare facilities were contaminated with approximately 107 cells per mL of Achromobacter species 3 (9 hospitals), Achromobacter xylosoxidans or Serratia marcescens (1 hospital each). In none of the hospitals dispenser processing had been adequately performed. Isolates regained susceptibility to the disinfectants after five passages without selection pressure but were still able to multiply in different formulations from different manufacturers at room temperature within 7 days. Conclusions Neglecting adequate processing of surface disinfectant dispensers has contributed to frequent and heavy contamination of use-solutions based on surface active ingredients. Tissue dispenser processing should be taken seriously in clinical practice. PMID:24447780
Characterization of Cold Sprayed CuCrAl Coated GRCop-84 Substrates for Reusable Launch Vehicles
NASA Technical Reports Server (NTRS)
Raj, S . V.; Barrett, C. A.; Lerch, B. A.; Karthikeyan, J.; Ghosn, L. J.; Haynes, J.
2005-01-01
An advanced Cu-8(at.%)Cr-4%Nb alloy developed at NASA's Glenn Research Center, and designated as GRCop-84, is currently being considered for use as combustor liners and nozzles in NASA's future generations of reusable launch vehicles (RLVs). Despite the fact that this alloy has superior mechanical and oxidation properties compared to many commercially available copper alloys, it is felt that its high temperature and environmental resistance capabilities can be further enhanced with the development and use of suitable coatings. Several coatings and processes are currently being evaluated for their suitability and future down selection. A newly developed CuCrAl has shown excellent oxidation resistance compared to current generation Cu-Cr coating alloys. Cold spray technology for depositing the CuCrAl coating on a GRCop-84 substrate is currently being developed under NASA's Next Generation Launch Technology (NGLT) Propulsion Research and Technology (PR&T) project. The microstructures, mechanical and thermophysical properties of overlay coated GRCop-84 substrates are discussed.
Closeup view of the exterior of the starboard side of ...
Close-up view of the exterior of the starboard side of the forward fuselage of the Orbiter Discovery looking at the forward facing observation windows of the flight deck. Note the High-temperature Reusable Surface Insulation (HRSI) surrounding the window openings, the Low-temperature Reusable Surface Insulation (LRSI) immediately beyond the HRSI tiles and the Advanced Flexible Reusable Surface Insulation blankets just beyond the LRSI tiles. The holes in the tiles are injection points for the application of waterproofing material. The windows are composed of redundant pressure window panes of thermal glass. This image was taken from a service platform in the Orbiter Processing Facility at Kennedy Space Center - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Heat Transfer Measurement and Modeling in Rigid High-Temperature Reusable Surface Insulation Tiles
NASA Technical Reports Server (NTRS)
Daryabeigi, Kamran; Knutson, Jeffrey R.; Cunnington, George R.
2011-01-01
Heat transfer in rigid reusable surface insulations was investigated. Steady-state thermal conductivity measurements in a vacuum were used to determine the combined contribution of radiation and solid conduction components of heat transfer. Thermal conductivity measurements at higher pressures were then used to estimate the effective insulation characteristic length for gas conduction modeling. The thermal conductivity of the insulation can then be estimated at any temperature and pressure in any gaseous media. The methodology was validated by comparing estimated thermal conductivities with published data on a rigid high-temperature silica reusable surface insulation tile. The methodology was also applied to the alumina enhanced thermal barrier tiles. Thermal contact resistance for thermal conductivity measurements on rigid tiles was also investigated. A technique was developed to effectively eliminate thermal contact resistance on the rigid tile s cold-side surface for the thermal conductivity measurements.
Aerodynamic heat transfer to RSI tile surfaces and gap intersections. [Reusable Surface Insulation
NASA Technical Reports Server (NTRS)
Dunavant, J. C.; Throckmorton, D. A.
1974-01-01
Review of the results of aerothermal heating tests of a simulated reusable surface insulation (RSI) tile array, performed on the sidewall of a Mach-10 hypersonic tunnel. In particular, the heating characteristics of the tile array, such as they result from heating inside the tile-expansion-space providing gaps between individual tiles, are investigated. The results include the finding that heating on the upstream face of a tile is strongly affected by the interacting longitudinal gap flow.
NASA Technical Reports Server (NTRS)
Chapman, A. J.
1973-01-01
Reusable surface insulation materials, which were developed as heat shields for the space shuttle, were tested over a range of conditions including heat-transfer rates between 160 and 620 kW/sq m. The lowest of these heating rates was in a range predicted for the space shuttle during reentry, and the highest was more than twice the predicted entry heating on shuttle areas where reusable surface insulation would be used. Individual specimens were tested repeatedly at increasingly severe conditions to determine the maximum heating rate and temperature capability. A silica-base material experienced only minimal degradation during repeated tests which included conditions twice as severe as predicted shuttle entry and withstood cumulative exposures three times longer than the best mullite material. Mullite-base materials cracked and experienced incipient melting at conditions within the range predicted for shuttle entry. Neither silica nor mullite materials consistently survived the test series with unbroken waterproof surfaces. Surface temperatures for a silica and a mullite material followed a trend expected for noncatalytic surfaces, whereas surface temperatures for a second mullite material appeared to follow a trend expected for a catalytic surface.
Guo, Kun; Hidalgo, Diana; Tommasi, Tonia; Rabaey, Korneel
2016-07-01
Scale up of bioelectrochemical systems (BESs) requires highly conductive, biocompatible and stable electrodes. Here we present pyrolytic carbon-coated stainless steel felt (C-SS felt) as a high-performance and scalable anode. The electrode is created by generating a carbon layer on stainless steel felt (SS felt) via a multi-step deposition process involving α-d-glucose impregnation, caramelization, and pyrolysis. Physicochemical characterizations of the surface elucidate that a thin (20±5μm) and homogenous layer of polycrystalline graphitic carbon was obtained on SS felt surface after modification. The carbon coating significantly increases the biocompatibility, enabling robust electroactive biofilm formation. The C-SS felt electrodes reach current densities (jmax) of 3.65±0.14mA/cm(2) within 7days of operation, which is 11 times higher than plain SS felt electrodes (0.30±0.04mA/cm(2)). The excellent biocompatibility, high specific surface area, high conductivity, good mechanical strength, and low cost make C-SS felt a promising electrode for BESs. Copyright © 2016 Elsevier Ltd. All rights reserved.
Bonding of reusable surface insulation with low density silicone foams
NASA Technical Reports Server (NTRS)
Hiltz, A. A.; Hockridge, R. R.; Curtis, F. P.
1972-01-01
The development and evaluation of a reduced density, high reliable foamed bond strain isolation system for attaching reusable surface insulation to the space shuttle structure are reported. Included are data on virgin materials as well as on materials that received 100 cycles of exposure to 650 F for approximately 20 minutes per cycle. Room temperature vulcanizing silicon elastomers meet all the requirments for an adhesive bonding system.
Attitude of US obstetricians and gynaecologists to global warming and medical waste.
Thiel, Cassandra; Duncan, Paula; Woods, Noe
2017-01-01
Objectives Global warming (or climate change) is a major public health issue, and health services are one of the largest contributors to greenhouse gas emissions in high-income countries. Despite the scale of the health care sector's resource consumption, little is known about the attitude of physicians and their willingness to participate in efforts to reduce the environmental impact of health services. Methods A survey of 236 obstetricians and gynaecologists at the University of Pittsburgh Medical Center in Western Pennsylvania, USA. Survey responses were compared to Gallup poll data from the general population using a one-sample test of proportions, Fisher's exact tests, Chi-square test, and logistic regression. Results Physicians in obstetrics and gynaecology were more likely than the public (84% vs. 54%; p<0.001) to believe that global warming is occurring, that media portrayal of its seriousness is accurate, and that it is caused by human activities. Two-thirds of physicians felt the amount of surgical waste generated is excessive and increasing. The majority (95%) would support efforts to reduce waste, with 66% favouring the use of reusable surgical tools over disposable where clinically equivalent. Despite their preference for reusable surgical instruments, only 20% preferred the reusable devices available to them. Conclusions Health care providers engaging in sustainability efforts may encounter significant support from physicians and may benefit from including physician leaders in their efforts.
Effective Thermal Conductivity of High Temperature Insulations for Reusable Launch Vehicles
NASA Technical Reports Server (NTRS)
Daryabeigi, Kamran
1999-01-01
An experimental apparatus was designed to measure the effective thermal conductivity of various high temperature insulations subject to large temperature gradients representative of typical launch vehicle re-entry aerodynamic heating conditions. The insulation sample cold side was maintained around room temperature, while the hot side was heated to temperatures as high as 1800 degrees Fahrenheit. The environmental pressure was varied from 0.0001 to 760 torr. All the measurements were performed in a dry gaseous nitrogen environment. The effective thermal conductivity of Saffil, Q-Fiber felt, Cerachrome, and three multi-layer insulation configurations were measured.
Kim, Ki Jae; Lee, Seung-Wook; Yim, Taeeun; Kim, Jae-Geun; Choi, Jang Wook; Kim, Jung Ho; Park, Min-Sik; Kim, Young-Jun
2014-01-01
The effects of surface treatment combining corona discharge and hydrogen peroxide (H2O2) on the electrochemical performance of carbon felt electrodes for vanadium redox flow batteries (VRFBs) have been thoroughly investigated. A high concentration of oxygen functional groups has been successfully introduced onto the surface of the carbon felt electrodes by a specially designed surface treatment, which is mainly responsible for improving the energy efficiency of VRFBs. In addition, the wettability of the carbon felt electrodes also can be significantly improved. The energy efficiency of the VRFB cell employing the surface modified carbon felt electrodes is improved by 7% at high current density (148 mA cm−2). Such improvement is attributed to the faster charge transfer and better wettability allowed by surface-active oxygen functional groups. Moreover, this method is much more competitive than other surface treatments in terms of processing time, production costs, and electrochemical performance. PMID:25366060
Yoon, Jai Hoon; Yoon, Byung Chul; Lee, Hang Lak; Lee, Jun Kyu; Kim, Yong-Tae; Lee, Dong Ho; Choi, Il Ju; Lee, Don Haeng; Kim, Dong Hee
2012-02-01
Every country has standardized reprocessing guidelines for reducing the risk of microorganism transmission via reusable biopsy forceps. Sterilization is performed either by autoclaving or with the use of ethylene oxide (EO) gas. However, there are no clear standard global recommendations. The aim of this study was to determine whether EO gas or autoclaving is a safer and more effective method for the sterilization of reusable forceps. This was a prospective study conducted at multiple tertiary referral centers. Seventy reusable biopsy forceps that had been reused at least 20 times each were collected from six endoscopy centers. In all, 61 forceps from five centers were sterilized using EO gas, and the nine forceps from the remaining center were placed in an autoclave. We performed real-time polymerase chain reaction (RT-PCR) for Mycobacterium tuberculosis and hepatitis B virus and performed bacterial cultures on the reusable forceps, which were cut into 2- to 3-cm sections. The forceps were also scanned with an electron microscope (EM) to detect surface damage and contamination. Escherichia coli bacteria were cultured from 2 of the 61 (3.3%) reusable biopsy forceps sterilized with EO gas. On EM scanning, abundant debris and tissue materials remained on the cup surfaces of the reused biopsy forceps and on their inner wires. No microorganisms were found on the autoclaved forceps. Sterilization with EO gas may be inadequate because the complicated structure of the forceps may interfere with sterilization. Therefore, for optimum safety, reusable biopsy forceps should be sterilized by autoclaving.
Guo, Kun; Donose, Bogdan C; Soeriyadi, Alexander H; Prévoteau, Antonin; Patil, Sunil A; Freguia, Stefano; Gooding, J Justin; Rabaey, Korneel
2014-06-17
Stainless steel (SS) can be an attractive material to create large electrodes for microbial bioelectrochemical systems (BESs), due to its low cost and high conductivity. However, poor biocompatibility limits its successful application today. Here we report a simple and effective method to make SS electrodes biocompatible by means of flame oxidation. Physicochemical characterization of electrode surface indicated that iron oxide nanoparticles (IONPs) were generated in situ on an SS felt surface by flame oxidation. IONPs-coating dramatically enhanced the biocompatibility of SS felt and consequently resulted in a robust electroactive biofilm formation at its surface in BESs. The maximum current densities reached at IONPs-coated SS felt electrodes were 16.5 times and 4.8 times higher than the untreated SS felts and carbon felts, respectively. Furthermore, the maximum current density achieved with the IONPs-coated SS felt (1.92 mA/cm(2), 27.42 mA/cm(3)) is one of the highest current densities reported thus far. These results demonstrate for the first time that flame oxidized SS felts could be a good alternative to carbon-based electrodes for achieving high current densities in BESs. Most importantly, high conductivity, excellent mechanical strength, strong chemical stability, large specific surface area, and comparatively low cost of flame oxidized SS felts offer exciting opportunities for scaling-up of the anodes for BESs.
Modal analysis and dynamic stresses for acoustically excited shuttle insulation tiles
NASA Technical Reports Server (NTRS)
Ojalvo, I. U.; Ogilvie, P. L.
1975-01-01
Improvements and extensions to the RESIST computer program developed for determining the normalized modal stress response of shuttle insulation tiles are described. The new version of RESIST can accommodate primary structure panels with closed-cell stringers, in addition to the capability for treating open-cell stringers. In addition, the present version of RESIST numerically solves vibration problems several times faster than its predecessor. A new digital computer program, titled ARREST (Acoustic Response of Reusable Shuttle Tiles) is also described. Starting with modal information contained on output tapes from RESIST computer runs, ARREST determines RMS stresses, deflections and accelerations of shuttle panels with reusable surface insulation tiles. Both programs are applicable to stringer stiffened structural panels with or without reusable surface insulation titles.
NASA Technical Reports Server (NTRS)
Ransone, P. O.; Morrison, J. D.; Minster, J. E.
1979-01-01
Tiles of space shuttle reusable surface insulation coated with reaction cured glass were subjected to 25 cycles of launch pad exposure and simulated mission heating. The coating could not withstand the environment without cracking. Water absorption after cracking reached as high as 150 weight percent. Exposure of insulation fibers beneath the coating to contaminants dissolved in absorbed water initiated fiber degradation.
System specification for the reusable reentry satellite
NASA Technical Reports Server (NTRS)
1991-01-01
The RRS design shall provide a relatively inexpensive method of access to micro and fractional gravity space environments for an extended period of time, with eventual intact recovery on the surface of the Earth. This specification establishes the performance, design, development, and test requirements for the Reusable Reentry Satellite (RRS) system.
A Non Rigid Reusable Surface Insulation Concept for the Space Shuttle Thermal Protection System
NASA Technical Reports Server (NTRS)
Alexander, J. G.
1973-01-01
A reusable thermal protection system concept was developed for the space shuttle that utilizes a flexible, woven ceramic mat insulation beneath an aerodynamic skin and moisture barrier consisting of either a dense ceramic coating or a super alloy metallic foil. The resulting heat shield material has unique structural characteristics. The shear modulus of the woven mat is very low such that bending and membrane loads introduced into the underlying structural panel remain isolated from the surface skin.
Reusable Surface Insulation Tile Thermal Protection Materials: Past, Present and the Future
NASA Technical Reports Server (NTRS)
Leiser, Daniel B.; Stewart, David A.; Venkatapathy, Ethiras (Technical Monitor)
2002-01-01
Silica (LI-900) Reusable Surface Insulation (RSI) tile have been used on the majority of the Shuttle since its initial flight. Its overall performance with Reaction Cured Glass (RCG) coating applied will be reviewed. Improvements in insulations, Fibrous Refractory Composite Insulation (FRCI-12) and Alumina Enhanced Thermal Barrier (AETB-8) and coatings/surface treatments such as Toughened Uni-Piece Fibrous Insulation (TUFI) have been developed and successfully applied. The performance of these enhancements on the Shuttle Orbiters over the past few years along with the next version of tile materials, High Efficiency Tantalum-based Ceramic (HETC) with even broader applicability will also be discussed.
Global Exploration Roadmap Derived Concept for Human Exploration of the Moon
NASA Technical Reports Server (NTRS)
Whitley, Ryan; Landgraf, Markus; Sato, Naoki; Picard, Martin; Goodliff, Kandyce; Stephenson, Keith; Narita, Shinichiro; Gonthier, Yves; Cowley, Aiden; Hosseini, Shahrzad;
2017-01-01
Taking advantage of the development of Mars-forward assets in cislunar space, a human lunar surface concept is proposed to maximize value for both lunar exploration and future deep space missions. The human lunar surface missions will be designed to build upon the cislunar activities that precede them, providing experience in planetary surface operations that cannot be obtained in cislunar space. To enable a five-mission limited campaign to the surface of the Moon, two new elements are required: a human lunar lander and a mobile surface habitat. The human lunar lander will have been developed throughout the cislunar phase from a subscale demonstrator and will consist of a descent module alongside a reusable ascent module. The reusable ascent module will be used for all five human lunar surface missions. Surface habitation, in the form of two small pressurized rovers, will enable 4 crew to spend up to 42 days on the lunar surface.
Design, Analysis and Qualification of Elevon for Reusable Launch Vehicle
NASA Astrophysics Data System (ADS)
Tiwari, S. B.; Suresh, R.; Krishnadasan, C. K.
2017-12-01
Reusable launch vehicle technology demonstrator is configured as a winged body vehicle, designed to fly in hypersonic, supersonic and subsonic regimes. The vehicle will be boosted to hypersonic speeds after which the winged body separates and descends using aerodynamic control. The aerodynamic control is achieved using the control surfaces mainly the rudder and the elevon. Elevons are deflected for pitch and roll control of the vehicle at various flight conditions. Elevons are subjected to aerodynamic, thermal and inertial loads during the flight. This paper gives details about the configuration, design, qualification and flight validation of elevon for Reusable Launch Vehicle.
HF/H2O2 treated graphite felt as the positive electrode for vanadium redox flow battery
NASA Astrophysics Data System (ADS)
He, Zhangxing; Jiang, Yingqiao; Meng, Wei; Jiang, Fengyun; Zhou, Huizhu; Li, Yuehua; Zhu, Jing; Wang, Ling; Dai, Lei
2017-11-01
In order to improve the electrochemical performance of the positive graphite felt electrode in vanadium flow redox battery, a novel method is developed to effectively modify the graphite felt by combination of etching of HF and oxidation of H2O2. After the etching of HF for the graphite felt at ambient temperature, abundant oxygen-containing functional groups were further introduced on the surface of graphite felt by hydrothermal treatment using H2O2 as oxidant. Benefiting from the surface etching and introduction of functional groups, mass transfer and electrode process can be improved significantly on the surface of graphite felt. VO2+/VO2+ redox reaction on the graphite felt modified by HF and H2O2 jointly (denote: GF-HF/H2O2) exhibits superior electrochemical kinetics in comparison with the graphite felt modified by single HF or H2O2 treatment. The cell using GF-HF/H2O2 as the positive electrode was assembled and its electrochemical properties were evaluated. The increase of energy efficiency of 4.1% for GF-HF/H2O2 at a current density of 50 mA cm-2 was obtained compared with the pristine graphite felt. The cell using GF-HF/H2O2 also demonstrated higher discharge capacity. Our study revealed that HF/H2O2 treatment is an efficient method to enhance the electrochemical performance of graphite felt, further improving the comprehensive energy storage performance of the vanadium flow redox battery.
Viability of a Reusable In-Space Transportation System
NASA Technical Reports Server (NTRS)
Jefferies, Sharon A.; McCleskey, Carey M.; Nufer, Brian M.; Lepsch, Roger A.; Merrill, Raymond G.; North, David D.; Martin, John G.; Komar, David R.
2015-01-01
The National Aeronautics and Space Administration (NASA) is currently developing options for an Evolvable Mars Campaign (EMC) that expands human presence from Low Earth Orbit (LEO) into the solar system and to the surface of Mars. The Hybrid in-space transportation architecture is one option being investigated within the EMC. The architecture enables return of the entire in-space propulsion stage and habitat to cis-lunar space after a round trip to Mars. This concept of operations opens the door for a fully reusable Mars transportation system from cis-lunar space to a Mars parking orbit and back. This paper explores the reuse of in-space transportation systems, with a focus on the propulsion systems. It begins by examining why reusability should be pursued and defines reusability in space-flight context. A range of functions and enablers associated with preparing a system for reuse are identified and a vision for reusability is proposed that can be advanced and implemented as new capabilities are developed. Following this, past reusable spacecraft and servicing capabilities, as well as those currently in development are discussed. Using the Hybrid transportation architecture as an example, an assessment of the degree of reusability that can be incorporated into the architecture with current capabilities is provided and areas for development are identified that will enable greater levels of reuse in the future. Implications and implementation challenges specific to the architecture are also presented.
NASA Technical Reports Server (NTRS)
Keen, Jill M.; DeWeese, Darrell C.; Key, Leigh W.
1997-01-01
At Kennedy Space Center (KSC), Thiokol Corporation provides the engineering to assemble and prepare the Space Shuttle Reusable Solid Rocket Motor (RSRM) for launch. This requires hand cleaning over 86 surfaces including metals, adhesives, rubber and electrical insulations, various painted surfaces and thermal protective materials. Due to the phase-out of certain ozone depleting chemical (ODC) solvents, all RSRM hand wipe operations being performed at KSC using l,l,1-trichloroethane (TCA) were eliminated. This presentation summarizes the approach used and the data gathered in the effort to eliminate TCA from KSC hand wipe operations.
Detail view of the leading and top edge of the ...
Detail view of the leading and top edge of the vertical stabilizer of the Orbiter Discovery showing the thermal protection system components with the white Advanced Flexible Reusable Surface Insulation (AFRSI) blanket and the black High-temperature Reusable Surface Insulation (HRSI) tiles along the outer edges. The marks seen on the HRSI tiles are injection point marks and holes for the application of waterproofing material. This view was taken from a service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
1998-08-10
In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, holds down a curtain while making a test sample of tile on a block 5-axis computerized numerical control milling machine. About 70 percent of a Space Shuttle orbiter’s external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. They are known as High-Temperature Reusable Surface Insulation (HRSI) tiles and Low-Temperature Reusable Surface Insulation (LRSI) tiles. Most HRSI tiles are 6 inches square, but may be as large as 12 inches in some areas, and 1 to 5 inches thick. LRSI tiles are generally 8 inches square, ranging from 0.2to 1-inch thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter
Budhathoki, Shyam Sundar; Bhattachan, Meika; Castro-Sánchez, Enrique; Sagtani, Reshu Agrawal; Rayamajhi, Rajan Bikram; Rai, Pramila; Sharma, Gaurav
2018-02-02
Menstrual hygiene management (MHM) is an essential aspect of hygiene for women and adolescent girls between menarche and menopause. Despite being an important issue concerning women and girls in the menstruating age group MHM is often overlooked in post-disaster responses. Further, there is limited evidence of menstrual hygiene management in humanitarian settings. This study aims to describe the experiences and perceptions of women and adolescent girls on menstrual hygiene management in post-earthquake Nepal. A mixed methods study was carried out among the earthquake affected women and adolescent girls in three villages of Sindhupalchowk district of Nepal. Data was collected using a semi-structured questionnaire that captured experiences and perceptions of respondents on menstrual hygiene management in the aftermath of the Nepal earthquake. Quantitative data were triangulated with in-depth interview regarding respondent's personal experiences of menstrual hygiene management. Menstrual hygiene was rated as the sixth highest overall need and perceived as an immediate need by 18.8% of the respondents. There were 42.8% women & girls who menstruated within first week of the earthquake. Reusable sanitary cloth were used by about 66.7% of the respondents before the earthquake and remained a popular method (76.1%) post-earthquake. None of the respondents reported receiving menstrual adsorbents as relief materials in the first month following the earthquake. Disposable pads (77.8%) were preferred by respondents as they were perceived to be clean and convenient to use. Most respondents (73.5%) felt that reusable sanitary pads were a sustainable choice. Women who were in the age group of 15-34 years (OR = 3.14; CI = (1.07-9.20), did not go to school (OR = 9.68; CI = 2.16-43.33), married (OR = 2.99; CI = 1.22-7.31) and previously used reusable sanitary cloth (OR = 5.82; CI = 2.33-14.55) were more likely to use the reusable sanitary cloth. In the immediate aftermath of the earthquake, women and girls completely depended on the use of locally available resources as adsorbents during menstruation. Immediate relief activities by humanitarian agencies, lacked MHM activities. Understanding the previous practice and using local resources, the reusable sanitary cloth is a way to address the menstrual hygiene needs in the post-disaster situations in Nepal.
Kampf, Günter; Degenhardt, Stina; Lackner, Sibylle; Ostermeyer, Christiane
2014-01-01
Background: It has recently been reported that reusable dispensers for surface disinfection tissues may be contaminated, especially with adapted Achromobacter species 3, when products based on surface-active ingredients are used. Fresh solution may quickly become recontaminated if dispensers are not processed adequately. Methods: We evaluated the abilities of six manual and three automatic processes for processing contaminated dispensers to prevent recolonisation of a freshly-prepared disinfectant solution (Mikrobac forte 0.5%). Dispensers were left at room temperature for 28 days. Samples of the disinfectant solution were taken every 7 days and assessed quantitatively for bacterial contamination. Results: All automatic procedures prevented recolonisation of the disinfectant solution when a temperature of 60–70°C was ensured for at least 5 min, with or without the addition of chemical cleaning agents. Manual procedures prevented recontamination of the disinfectant solution when rinsing with hot water or a thorough cleaning step was performed before treating all surfaces with an alcohol-based disinfectant or an oxygen-releaser. Other cleaning and disinfection procedures, including the use of an alcohol-based disinfectant, did not prevent recolonisation. Conclusions: These results indicate that not all processes are effective for processing reusable dispensers for surface-disinfectant tissues, and that a high temperature during the cleaning step or use of a biofilm-active cleaning agent are essential. PMID:24653973
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tian, Chengcheng; Bao, Chunhui; Binder, Andrew
We employed poly(4-styrenesulfonic acid) brush-grafted silica particles, synthesized by surface-initiated atom transfer radical polymerization, as a reusable acid catalyst for dehydration of fructose to 5-hydroxymethylfurfural (HMF) in water. Furthermore, the particles exhibited a high activity with the HMF yield of up to 31%, in contrast to 26% from the corresponding free homopolymer catalyst.
Self-unloading, reusable, lunar lander project
NASA Technical Reports Server (NTRS)
Arseculeratne, Ruwan; Cavazos, Melissa; Euker, John; Ghavidel, Fred; Hinkel, Todd J.; Hitzfelder, John; Leitner, Jesse; Nevik, James; Paynter, Scott; Zolondek, Allen
1990-01-01
In the early 21st century, NASA will return to the Moon and establish a permanent base. To achieve this goal safely and economically, B&T Engineering has designed an unmanned, reusable, self-unloading lunar lander. The lander is designed to deliver 15,000 kg payloads from an orbit transfer vehicle (OTV) in a low lunar polar orbit and an altitude of 200 km to any location on the lunar surface.
Magnetic Carbon Microspheres as a Reusable Adsorbent for Sulfonamide Removal from Water
NASA Astrophysics Data System (ADS)
Dai, Kewei; Wang, Fenghe; Jiang, Wei; Chen, Yajun; Mao, Jing; Bao, Jian
2017-09-01
Novel reusable magnetic carbon microspheres (MCMs) were prepared by hydrothermal method with glucose as carbon source and Fe3O4 nanoparticles as magnetic raw materials. And adsorption performance of MCMs for sulfonamide removal from water was investigated in detail. The results indicated that the calcination temperature and calcination time had significant effects on the surface area and its volume porous of MCMs. When MCMs were calcined in 600 °C for 1 h, the surface area and volume porous of MCMs were 1228 m2/g and 0.448 m3/g, respectively. The adsorption results showed that the adsorption data fitted well with the Langmuir isotherm model and followed pseudo-second-order kinetics. When the pH value was changed from 4.0 to 10.0, the adsorption capacity of MCMs for sulfonamide was decreased from 24.6 to 19.2 mg/g. The adsorption capacity of as-synthesized MCMs achieved 18.31 mg/g after it was reused four times, which exhibited a desirable adsorption capacity and reusability.
Akhmal Saadon, Syaiful; Sathishkumar, Palanivel; Mohd Yusoff, Abdull Rahim; Hakim Wirzal, Mohd Dzul; Rahmalan, Muhammad Taufiq; Nur, Hadi
2016-08-01
In this study, the zinc oxide (ZnO) layer was synthesised on the surface of Zn plates by three different techniques, i.e. electrolysis, hydrogen peroxide and heat treatment. The synthesised ZnO layers were characterised using scanning electron microscopy, X-ray diffraction, UV-visible diffuse reflectance and photoluminescence spectroscopy. The photocatalytic activity of the ZnO layer was further assessed against methylene blue (MB) degradation under UV irradiation. The photocatalytic degradation of MB was achieved up to 84%, 79% and 65% within 1 h for ZnO layers synthesised by electrolysis, heat and hydrogen peroxide treatment, respectively. The reusability results show that electrolysis and heat-treated ZnO layers have considerable photocatalytic stability. Furthermore, the results confirmed that the photocatalytic efficiency of ZnO was directly associated with the thickness and enlarged surface area of the layer. Finally, this study proved that the ZnO layers synthesised by electrolysis and heat treatment had shown better operational stability and reusability.
Tony Rollins fashions a new tile for the Space Shuttle orbiter
NASA Technical Reports Server (NTRS)
1998-01-01
In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, holds down a curtain while making a test sample of tile on a block 5-axis computerized numerical control milling machine. About 70 percent of a Space Shuttle orbiter's external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. They are known as High-Temperature Reusable Surface Insulation (HRSI) tiles and Low-Temperature Reusable Surface Insulation (LRSI) tiles. Most HRSI tiles are 6 inches square, but may be as large as 12 inches in some areas, and 1 to 5 inches thick. LRSI tiles are generally 8 inches square, ranging from 0.2- to 1-inch thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter.
NASA Technical Reports Server (NTRS)
Taylor, A. H.; Jackson, L. R.; Weinstein, I.
1977-01-01
Three thermal protection systems proposed for a hypersonic research airplane were subjected to high heating rates in the Langley 8 foot, high temperature structures tunnel. Metallic heat sink (Lockalloy), reusable surface insulation, and insulator-ablator materials were each tested under similar conditions. The specimens were tested for a 10 second exposure on the windward side of an elevon deflected 30 deg. The metallic heat sink panel exhibited no damage; whereas the reusable surface insulation tiles were debonded from the panel and the insulator-ablator panel eroded through its thickness, thus exposing the aluminum structure to the Mach 7 environment.
NASA Technical Reports Server (NTRS)
Owen, H. P.; Carroll, M. T.
1973-01-01
The task consisted of conducting mechanical and thermal tests to establish design allowables data on a new room temperature vulcanizing (RTV) silicone adhesive, X3-6004. Low modulus, coupled with relatively low density and good low-temperature properties of this adhesive, places it in contention as a candidate for attaching reusable surface insulation on the space shuttle. Data obtained show that the modulus values of X3-6004 are significantly lower than those of RTV-560 and the other three adhesives characterized at test temperatures from 550 to -175 F. At -175, -200 and -270 F, the modulus of X3-6004 is approximately the same as GE RTV-560 and the other three silicone adhesives. The X3-6004 adhesive exhibits good processing properties. It has a 12 percent lower density than RTV-560. Although lower in overall strength properties as compared to the other adhesives in the program, X3-6004 has adequate adhesion to 2024T81 aluminum to compete as an adhesive for attaching reusable surface insulation. It does exhibit some tendency to revert and soften at temperatures above 350 F when in a confined area.
X-34 Experimental Aeroheating at Mach 6 and 10
NASA Technical Reports Server (NTRS)
Berry, Scott A.; Horvath, Thomas J.; DiFulvio, Michael; Glass, Christopher; Merski, N. Ronald
1998-01-01
Critical technologies are being developed to support the goals of the NASA Office of Aeronautics and Space Transportation Technology Access to Space initiative for next-generation reusable space transportation systems. From the perspective of aerothermodynamic performance throughout the flight trajectory, the Reusable Launch Vehicle program incorporates conceptual analysis, ground-based testing, and computational fluid dynamics to provide flyable suborbital flight demonstrator vehicles. This report provides an overview of the hypersonic aeroheating wind tunnel test program conducted at the NASA Langley Research Center in support of one of these vehicles, the X-34 small reusable technology demonstrator program. Global surface heat transfer images, surface streamline patterns, and shock shapes were measured on 0.0153- and 0.0183-scale models of proposed X-34 flight vehicles at Mach 6 and 10 in air. The primary parametrics that were investigated include angles-of-attack from 0 to 35 deg. and freestream unit Reynolds numbers from 0.5 to 8 million per foot (which was sufficient to produce laminar, transitional, and turbulent heating data), both with and without control surface deflections. Comparisons of the experimental data to computational predictions are included, along with a discussion of the implications of some of the experimental flow features for the flight vehicle.
Wang, Jianfeng; Liu, Zhongmei; Zhou, Zhemin
2017-06-01
Chelating of pullulanases onto nickel (II)-modified magnetic nanoparticles results in one-step purification and immobilization of pullulanase, and facilitates the commercial application of pullulanase in industrial scale. To improve the catalytic behavior, especially the operational stability, of the nanocatalyst in consecutive batch reactions, we prepared various iminodiacetic acid-modified magnetic nanoparticles differed in surface polarity and spacer length, on which the His6-tagged pullulanases were chelated via nickel ions, and then studied the correlation between the MNPs surface property and the corresponding catalyst behavior. When pullulanases were chelated onto the surface-modified MNPs, the thermostability of all pullulanase derivatives were lower than that of free counterpart, being not relevant to the protein orientation guided by the locality of the His6-tag, but related to the MNPs basal surface polarity and the grafted spacer length. After chelating of pullulanases onto MNPs, there were changes observed in the pH-activity profile and the apparent Michaelis constant toward pullulan. The changing tendencies were mainly dependent on the His6-tagged pullulanase orientation, and the changing extents were tuned by the spacer length. The reusability of pullulanase immobilized by N-terminal His6-tag was higher than that of pullulanase immobilized by C-terminal His6-tag. Moreover, the reusability of the immobilized pullulanase tested increased till grafting polyether amine-400 as spacer-arm, therefore the N-terminal His6-tagged pullulanase chelating MNPs grafted polyether amine-400 gave the best reusability, which retained 60% of initial activity after 18 consecutive cycles with a total reaction time of 9h. Additionally, the correlation analysis of the catalyst behaviors indicated that the reusability was independent from other catalytic properties such as thermostability and substrate affinity. All the results revealed that the catalyst behavior can be mainly controlled by the His6-tagged pullulanase orientation than by the MNPs surface property which can tune the catalyst function. Copyright © 2017. Published by Elsevier Inc.
Transonic aerodynamic characteristics of a proposed wing-body reusable launch vehicle concept
NASA Technical Reports Server (NTRS)
Springer, A. M.
1995-01-01
A proposed wing-body reusable launch vehicle was tested in the NASA Marshall Space Flight Center's 14 x 14-inch trisonic wind tunnel during the winter of 1994. This test resulted in the vehicle's subsonic and transonic, Mach 0.3 to 1.96, longitudinal and lateral aerodynamic characteristics. The effects of control surface deflections on the basic vehicle's aerodynamics, including a body flap, elevons, ailerons, and tip fins, are presented.
NASA Astrophysics Data System (ADS)
Dixon, D.; Babu, D. J.; Langner, J.; Bruns, M.; Pfaffmann, L.; Bhaskar, A.; Schneider, J. J.; Scheiba, F.; Ehrenberg, H.
2016-11-01
Oxygen plasma treatment was applied on commercially available graphite felt electrodes based on rayon (GFA) and polyacrylonitrile (GFD). The formation of functional groups on the surface of the felt was confirmed by X-ray photoelectron spectroscopy measurements. The BET studies of the plasma treated electrodes showed no significant increase in surface area for both the rayon as well as the PAN based felts. Both plasma treated electrodes showed significantly enhanced V3+/V2+ redox activity compared to the pristine electrodes. Since an increase of the surface area has been ruled out for plasma treated electrode the enhanced activity could be attributed to surface functional groups. Interestingly, plasma treated GFD felts showed less electrochemical activity towards V5+/V4+ compared to the pristine electrode. Nevertheless, an overall increase of the single cell performance was still observed as the negative electrode is known to be the performance limiting electrode. Thus, to a great extent the present work helps to preferentially understand the importance of functional groups on the electrochemical activity of negative and positive redox reaction. The study emphasizes the need of highly active electrodes especially at the negative electrode side as inactive electrodes can still facilitate hydrogen evolution and degrade the electrolyte in VRFBs.
Tebbutt, G. M.
1988-01-01
A comparison of five methods of cleaning Formica surfaces contaminated with bacteria dried in milk has been carried out. A standardized procedure was developed, and impression plates were found to be at least as sensitive as a swab-rinse method for detecting bacteria on the surfaces. The most satisfactory results were obtained with one type of disposable alcohol-impregnated wipe and with a detergent/hypochlorite solution applied with paper. A reusable cloth impregnated with disinfectant initially performed well against all test organisms, but was less reliable against Staphylococcus aureus and Streptococcus faecalis, after the cloth had been used and rinsed several times. The importance of introducing methods to reduce the high risk of cross-contamination presently associated with the use of wiping cloths in catering premises is stressed. PMID:3141202
Wei, Zuojun; Lou, Jiongtao; Su, Chuanmin; Guo, Dechao; Liu, Yingxin; Deng, Shuguang
2017-04-22
To achieve a higher activity and reusability of a Ru-based catalyst, Ru nanoparticles were embedded in N-doped mesoporous carbon through a hard-template method. The catalyst showed excellent catalytic performance (314 h -1 turnover frequency) and recyclability (reusable five times with 3 % activity loss) for the hydrogenolysis of levulinic acid to γ-valerolactone. Compared with the mesoporous carbon without N-doping and conventional activated carbon, the introduction of N-dopant effectively improved the dispersion of Ru nanoparticles, decreased the average size of Ru nanoparticles to as small as 1.32 nm, and improved the adsorption of levulinic acid, which contributed to the increase in the activity of the catalyst. Additionally, the embedding method increased the interaction between Ru nanoparticles and carbon support in contrast with the conventional impregnation method, thus preventing the Ru nanoparticles from migration, aggregation, and leaching from the carbon surface and therefore increasing the reusability of the catalyst. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Self-unloading, unmanned, reusable lunar lander project
NASA Technical Reports Server (NTRS)
Cowan, Kevin; Lewis, Ron; Mislinski, Philip; Rivers, Donna; Smith, Solar; Vasicek, Clifford; Verona, Matt
1991-01-01
A payload delivery system will be required to support the buildup and operation of a manned lunar base. In response, a self-unloading, unmanned, reusable lunar lander was conceptually designed. The lander will deliver a 7000 kg payload, with the same dimensions as a space station logistics module, from low lunar orbit to any location on the surface of the moon. The technical aspects of the design is introduced as well as the management structure and project cost.
Heat-treated stainless steel felt as scalable anode material for bioelectrochemical systems.
Guo, Kun; Soeriyadi, Alexander H; Feng, Huajun; Prévoteau, Antonin; Patil, Sunil A; Gooding, J Justin; Rabaey, Korneel
2015-11-01
This work reports a simple and scalable method to convert stainless steel (SS) felt into an effective anode for bioelectrochemical systems (BESs) by means of heat treatment. X-ray photoelectron spectroscopy and cyclic voltammetry elucidated that the heat treatment generated an iron oxide rich layer on the SS felt surface. The iron oxide layer dramatically enhanced the electroactive biofilm formation on SS felt surface in BESs. Consequently, the sustained current densities achieved on the treated electrodes (1 cm(2)) were around 1.5±0.13 mA/cm(2), which was seven times higher than the untreated electrodes (0.22±0.04 mA/cm(2)). To test the scalability of this material, the heat-treated SS felt was scaled up to 150 cm(2) and similar current density (1.5 mA/cm(2)) was achieved on the larger electrode. The low cost, straightforwardness of the treatment, high conductivity and high bioelectrocatalytic performance make heat-treated SS felt a scalable anodic material for BESs. Copyright © 2015 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Pan, Minqiang; Zhong, Yujian
2018-01-01
Porous structure can effectively enhance the heat transfer efficiency. A kind of micro vaporizer using the oriented linear cutting copper fiber sintered felt is proposed in this work. Multiple long cutting copper fibers are firstly fabricated with a multi-tooth tool and then sintered together in parallel to form uniform thickness metal fiber sintered felts that provided a characteristic of oriented microchannels. The temperature rise response and thermal conversion efficiency are experimentally investigated to evaluate the influences of porosity, surface structure, feed flow rate and input power on the evaporation characteristics. It is indicated that the temperature rise response of water is mainly affected by input power and feed flow rate. High input power and low feed flow rate present better temperature rise response of water. Porosity rather than surface structure plays an important role in the temperature rise response of water at a relatively high input power. The thermal conversion efficiency is dominated by the input power and surface structure. The oriented linear cutting copper fiber sintered felts for three kinds of porosities show better thermal conversion efficiency than that of the oriented linear copper wire sintered felt when the input power is less than 115 W. All the sintered felts have almost the same performance of thermal conversion at a high input power.
NASA Astrophysics Data System (ADS)
Park, J.-S.; Park, J.-H.; Lee, D.-W.
2018-02-01
In this paper, we describe a simple manufacturing method for producing an optically transparent super-hydrophobic polymer thin film using a reusable photo-curable polymer mold. Soluble photoresist (PR) molds were prepared with under-exposed and under-baked processes, which created unique hierarchical micro/nano structures. The reverse phase of the PR mold was replicated on the surface of polydimethylsiloxane (PDMS) substrates. The unique patterns on the replicated PDMS molds were successfully transferred back to the UV curable polyurethane-acrylate (PUA) using a laboratory-made UV exposure system. Continuous production of the super-hydrophobic PDMS thin film was demonstrated using the reusable PUA mold. In addition, hydrophobic nano-silica powder was sprayed onto the micro/nano structured PDMS surfaces to further improve hydrophobicity. The fabricated PDMS thin films with hierarchical surface texturing showed a water contact angle ⩾150°. Excellent optical transmittance within the range of visible light of wavelengths between 400-800 nm was experimentally confirmed using a spectrophotometer. High efficiency of the super-hydrophobic PDMS film in optical transparency was also confirmed using solar panels. The fabricated PUA molds are very suitable for use in roll-to-roll or roll-to-plate systems which allow continuous production of super-hydrophobic thin films with an excellent optical transparency.
A ceramic matrix composite thermal protection system for hypersonic vehicles
NASA Technical Reports Server (NTRS)
Riccitiello, Salvatore R.; Love, Wendell L.; Pitts, William C.
1993-01-01
The next generation of hypersonic vehicles (NASP, SSTO) that require reusable thermal protection systems will experience acreage surface temperatures in excess of 1100 C. More important, they will experience a more severe physical environment than the Space Shuttle due to non-pristine launching and landing conditions. As a result, maintenance, inspection, and replacement factors must be more thoroughly incorporated into the design of the TPS. To meet these requirements, an advanced thermal protection system was conceived, designated 'TOPHAT'. This system consists of a toughened outer ceramic matrix composite (CMC) attached to a rigid reusable surface insulator (RSI) which is directly bonded to the surface. The objective of this effort was to evaluate this concept in an aeroconvective environment, to determine the effect of impacts to the CMC material, and to compare the results with existing thermal protection systems.
Process of making titanium carbide (TiC) nano-fibrous felts
Fong, Hao; Zhang, Lifeng; Zhao, Yong; Zhu, Zhengtao
2015-01-13
A method of synthesizing mechanically resilient titanium carbide (TiC) nanofibrous felts comprising continuous nanofibers or nano-ribbons with TiC crystallites embedded in carbon matrix, comprising: (a) electrospinning a spin dope for making precursor nanofibers with diameters less than 0.5 J.Lm; (b) overlaying the nanofibers to produce a nanofibrous mat (felt); and then (c) heating the nano-felts first at a low temperature, and then at a high temperature for making electrospun continuous nanofibers or nano-ribbons with TiC crystallites embedded in carbon matrix; and (d) chlorinating the above electrospun nano-felts at an elevated temperature to remove titanium for producing carbide derived carbon (CDC) nano-fibrous felt with high specific surface areas.
Reusable crucible for containing corrosive liquids
de Pruneda, Jean A. H.
1995-01-01
A reusable, non-wetting, corrosion-resistant material suitable for containment of corrosive liquids is formed of a tantalum or tantalum alloy substrate that is permeated with carbon atoms. The substrate is carburized to form surface layers of TaC and Ta.sub.2 C, and then is heated at high temperature under vacuum until the carbon atoms in the carbide layers diffuse throughout the substrate to form a solid solution of carbon atoms randomly interspersed in the tantalum or tantalum alloy lattice.
NASA Technical Reports Server (NTRS)
Unal, Resit; Morris, W. Douglas; White, Nancy H.; Lepsch, Roger A.; Brown, Richard W.
2000-01-01
This paper describes the development of parametric models for estimating operational reliability and maintainability (R&M) characteristics for reusable vehicle concepts, based on vehicle size and technology support level. A R&M analysis tool (RMAT) and response surface methods are utilized to build parametric approximation models for rapidly estimating operational R&M characteristics such as mission completion reliability. These models that approximate RMAT, can then be utilized for fast analysis of operational requirements, for lifecycle cost estimating and for multidisciplinary sign optimization.
Reusable crucible for containing corrosive liquids
Pruneda, J.A.H. de.
1995-01-24
A reusable, non-wetting, corrosion-resistant material suitable for containment of corrosive liquids is formed of a tantalum or tantalum alloy substrate that is permeated with carbon atoms. The substrate is carburized to form surface layers of TaC and Ta[sub 2]C, and then is heated at high temperature under vacuum until the carbon atoms in the carbide layers diffuse throughout the substrate to form a solid solution of carbon atoms randomly interspersed in the tantalum or tantalum alloy lattice. 10 figures.
Assessment of Alternate Thermal Protection Systems for the Space Shuttle Orbiter
NASA Technical Reports Server (NTRS)
Kelly, H. N.; Webb, G. L.
1982-01-01
Candidate concepts are identified. The impact on the Shuttle Orbiter performance life cycle cost, and risk was assessed and technology advances required to bring the selected TPS to operational readiness are defined. The best system is shown to be a hybrid blend of metallic and carbon-carbon TPS concepts. These alternate concepts offer significant improvements in reusability and are mass competitive with the current ceramic tile reusable surface insulation. Programmatic analysis indicates approximately five years are required to bring the concepts to operational readiness.
Structures and materials technology issues for reusable launch vehicles
NASA Technical Reports Server (NTRS)
Dixon, S. C.; Tenney, D. R.; Rummler, D. R.; Wieting, A. R.; Bader, R. M.
1985-01-01
Projected space missions for both civil and defense needs require significant improvements in structures and materials technology for reusable launch vehicles: reductions in structural weight compared to the Space Shuttle Orbiter of up to 25% or more, a possible factor of 5 or more increase in mission life, increases in maximum use temperature of the external surface, reusable containment of cryogenic hydrogen and oxygen, significant reductions in operational costs, and possibly less lead time between technology readiness and initial operational capability. In addition, there is increasing interest in hypersonic airbreathing propulsion for launch and transmospheric vehicles, and such systems require regeneratively cooled structure. The technology issues are addressed, giving brief assessments of the state-of-the-art and proposed activities to meet the technology requirements in a timely manner.
Characterization of cement-based materials using a reusable piezoelectric impedance-based sensor
NASA Astrophysics Data System (ADS)
Tawie, R.; Lee, H. K.
2011-08-01
This paper proposes a reusable sensor, which employs a piezoceramic (PZT) plate as an active sensing transducer, for non-destructive monitoring of cement-based materials based on the electromechanical impedance (EMI) sensing technique. The advantage of the sensor design is that the PZT can be easily removed from the set-up and re-used for repetitive tests. The applicability of the sensor was demonstrated for monitoring of the setting of cement mortar. EMI measurements were performed using an impedance analyzer and the transformation of the specimen from the plastic to solid state was monitored by automatically measuring the changes in the PZT conductance spectra with respect to curing time using the root mean square deviation (RMSD) algorithm. In another experiment, drying-induced moisture loss of a hardened mortar specimen at saturated surface dry (SSD) condition was measured, and monitored using the reusable sensor to establish a correlation between the RMSD values and moisture loss rate. The reusable sensor was also demonstrated for detecting progressive damages imparted on a mortar specimen attached with the sensor under several loading levels before allowing it to load to failure. Overall, the reusable sensor is an effective and efficient monitoring device that could possibly be used for field application in characterization of cement-based materials.
Catalytic recombination of nitrogen and oxygen on high-temperature reusable surface insulation
NASA Technical Reports Server (NTRS)
Scott, C. D.
1980-01-01
The energy transfer catalytic recombination coefficient for nitrogen and oxygen recombination on the surface coating of high-temperature reusable surface insulation (HRSI) is inferred from stagnation point heat flux measurements in a high-temperature dissociated arc jet flow. The resulting catalytic recombination coefficients are correlated with an Arrhenius model for convenience, and these expressions may be used to account for catalytic recombination effects in predictions of the heat flux on the HRSI thermal protection system of the Space Shuttle Orbiter during reentry flight. Analysis of stagnation point pressure and total heat balance enthalpy measurements indicates that the arc heater reservoir conditions are not in chemical equilibrium. This is contrary to what is usually assumed for arc jet analysis and indicates the need for suitable diagnostics and analyses, especially when dealing with chemical reaction phenomena such as catalytic recombination heat transfer effects.
Hercules Single-Stage Reusable Vehicle (HSRV) Operating Base
NASA Technical Reports Server (NTRS)
Moon, Michael J.; McCleskey, Carey M.
2017-01-01
Conceptual design for the layout of lunar-planetary surface support systems remains an important area needing further master planning. This paper explores a structured approach to organize the layout of a Mars-based site equipped for routinely flying a human-scale reusable taxi system. The proposed Hercules Transportation System requires a surface support capability to sustain its routine, affordable, and dependable operation. The approach organizes a conceptual Hercules operating base through functional station sets. The station set approach will allow follow-on work to trade design approaches and consider technologies for more efficient flow of material, energy, and information at future Mars bases and settlements. The station set requirements at a Mars site point to specific capabilities needed. By drawing from specific Hercules design characteristics, the technology requirements for surface-based systems will come into greater focus. This paper begins a comprehensive process for documenting functional needs, architectural design methods, and analysis techniques necessary for follow-on concept studies.
A ceramic matrix composite thermal protection system for hypersonic vehicles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Riccitiello, S.R.; Love, W.L.; Pitts, W.C.
1993-07-01
The next generation of hypersonic vehicles (NASP, SSTO) that require reusable thermal protection systems will experience acreage surface temperatures in excess of 1100 C. More important, they will experience a more severe physical environment than the Space Shuttle due to non-pristine launching and landing conditions. As a result, maintenance, inspection, and replacement factors must be more thoroughly incorporated into the design of the TPS. To meet these requirements, an advanced thermal protection system was conceived, designated 'TOPHAT'. This system consists of a toughened outer ceramic matrix composite (CMC) attached to a rigid reusable surface insulator (RSI) which is directly bondedmore » to the surface. The objective of this effort was to evaluate this concept in an aeroconvective environment, to determine the effect of impacts to the CMC material, and to compare the results with existing thermal protection systems. 10 refs.« less
Sustaining Human Presence on Mars Using ISRU and a Reusable Lander
NASA Technical Reports Server (NTRS)
Arney, Dale C.; Jones, Christopher A.; Klovstad, Jordan J.; Komar, D.R.; Earle, Kevin; Moses, Robert; Shyface, Hilary R.
2015-01-01
This paper presents an analysis of the impact of ISRU (In-Site Resource Utilization), reusability, and automation on sustaining a human presence on Mars, requiring a transition from Earth dependence to Earth independence. The study analyzes the surface and transportation architectures and compared campaigns that revealed the importance of ISRU and reusability. A reusable Mars lander, Hercules, eliminates the need to deliver a new descent and ascent stage with each cargo and crew delivery to Mars, reducing the mass delivered from Earth. As part of an evolvable transportation architecture, this investment is key to enabling continuous human presence on Mars. The extensive use of ISRU reduces the logistics supply chain from Earth in order to support population growth at Mars. Reliable and autonomous systems, in conjunction with robotics, are required to enable ISRU architectures as systems must operate and maintain themselves while the crew is not present. A comparison of Mars campaigns is presented to show the impact of adding these investments and their ability to contribute to sustaining a human presence on Mars.
Response Surface Model Building Using Orthogonal Arrays for Computer Experiments
NASA Technical Reports Server (NTRS)
Unal, Resit; Braun, Robert D.; Moore, Arlene A.; Lepsch, Roger A.
1997-01-01
This study investigates response surface methods for computer experiments and discusses some of the approaches available. Orthogonal arrays constructed for computer experiments are studied and an example application to a technology selection and optimization study for a reusable launch vehicle is presented.
TPS Materials and Costs for Future Reusable Launch Vehicles
NASA Technical Reports Server (NTRS)
Rasky, Dan J.; Milos, Frank S.; Squire, Tom H.; Arnold, James O. (Technical Monitor)
2000-01-01
There is considerable interest in developing new reusable launch vehicles (RLVs) for reducing the cost of transporting payload to and from orbit. This work reviews thirteen candidate thermal protection system (TPS) options currently available for RLVs. It is useful to begin with the current Shuttle TPS layout as a reference. The nose cap and wing leading edge , which reach the highest temperatures, are made of reinforced carbon-carbon (RCC) that is protected from oxidation by an external coating (about 0.020" thick) of silicon-carbide. Most of the windward surface is 9 lb/cubic ft ceramic tiles (LI-900) with a thin (about 0.012") coating of Reaction Cured Glass (RCG). The leeward side of the vehicle is covered largely by AFRSI, a quilted ceramic blanket, and FRSI, a polyamide felt. These four materials can be considered first generation reusable TPS. Since the time of the Shuttle design, considerable progress has been made advancing TPS technologies in terms of thermal performance, robustness, and cost. For each of the major systems, a second generation ceramic TPS has been developed, tested, and characterized. Metallic-based systems have also been developed. For applications requiring RCC in the past, advanced carbon-carbon (ACC) is now available. This material has better mechanical properties, somewhat higher temperature capability to 2900F and greatly increased oxidation resistance. New carbon fiber reinforced silicon-carbide matrix composites (C/SiCs) have shown additional improvement in properties over ACC with use temperatures to 3000F and above. For rigid tiles, NASA Ames has made two significant advancements. The first is a tile substrate called Alumina Enhanced Thermal Barrier, or AETB, that incorporates alumina fibers for improved dimensional stability at high temperatures, to 2600F and above. This material can be made to densities as low as 8 lb/cubic ft. The second is a coating preparation called Toughened Uni-piece Fibrous Insulation, or TUFT, that penetrates about 0.1 in. into the tile substrate. The resulting composite, with a functionally gradient density near the surface, provides orders of magnitude increased damage resistance compared with RCG coated LI-900, with only a small weight increase. The TPS that combines these two developments is called AETB-8/TUFI and has been adopted for high damage areas on the Shuttles. Two notable developments have occur-red in flexible ceramic blanket technology. The first is aluminoborosilicate-based fibers with use temperatures of 2200F and above," in comparison to quartz and silica fiber used in AFRSI which have multi-use temperature limits of 1200 to 1400F. Blankets incorporating these new high temperature fibers are referred to as AFRSI-HT. The second is an integral weaving techniques that produces a fluted core blanket with a smoother surface and greater resistance to aero-acoustic noise, to levels as high as 170 dB. This Ames innovation is called Tailorable Advanced Blanket Insulation, or TABI. Finally, for felt-based TPS, Boeing is developing Polybenzimidazole Blanket Insulation, or PBI, with a multi-use temperature limit of 1000F and above, in contrast to Shuttle FRSI which has a multi-use temperature limit of about 700F. 1.6 NASA Langley and BF Goodrich (formerly Rohr Corp.) have led the development of metallic-based TPS. This activity uses essentially three approaches: metallic tiles which encase a fibrous ceramic batting in a box fabricated largely from metallic honeycombs, typically Nickel based alloys; metallic honeycomb sheets, made of Nickel-based alloys, incorporating a fibrous back-side insulation encapsulated in a metallic foil bag, providing reduced weight; and metallic multi-wall, which is comprised of dimpled Titanium metal sheets, which are stacked and then diffusion bonded at contact points to form the TPS. The Nickel-based systems can be used up to temperatures of about 1800F, and the Titanium system to about 100F. These thirteen TPS materials have pros and cons to their usage in terms of temperature capability, weight, initial cost, and maintenance. Carbon-carbon and C/SiC systems have the highest temperature capability but are relatively expensive and heavy, requiring significant time, expertise, and costly facilities and tools for design and fabrication. Second generation ceramic tiles are relatively light, durable, simple to fabricate and easy to install; however, waterproofing is a concern. Blankets and felts are light, simple, inexpensive, and easy to install over curved vehicle surfaces, but durability and waterproofing are concerns. Metallics are robust and appear to have eliminated waterproofing, but they tend to be heavy and relatively expensive, requiring costly facilities and tools. If thin metal sheets are used to reduce weights, then issues arise from possible metal fatigue and corrosion caused by thermal cycling, pressure oscillations, and environmental exposure. For application to future RLVs, system analyses show that a significant component of the vehicle life cycle cost is from the TPS; however, it is difficult to quantify and to compare the potential savings of advanced systems without performing full vehicle designs using each of the different options. Because this entails a considerable effort and also tends to submerge TPS cost impacts under unrelated vehicle design assumptions, there is a clear need for a simpler quantitative method to evaluate the cost impact of different TPS options. To this end, this work introduces a TPS life-cycle cost parameter which is easily computed and applicable to generic RLVs.
Roh, Sung-Hee; Kim, Sun-Il
2012-05-01
A microbial fuel cell (MFC) is a device that converts chemical energy to electrical energy using the catalytic reaction of microorganisms. We investigated the performance of mediator-less MFC with carbon nanotubes (CNTs)/graphite felt composite electrodes. The addition of CNTs to a graphite felt electrode increases the specific surface area of the electrode and enhances the charge transfer capability so as to cause considerable improvement of the electrochemical activity for the anode reaction in a MFC. The performance of the MFC using CNTs/graphite felt electrode has been compared against a plain graphite felt electrode based MFC. A CNTs/graphite felt electrode showed as high as 15% increase in the power density (252 mW/m2) compared to graphite felt electrode (214 mW/m2). The CNTs/graphite felt anode therefore offers good prospects for application in MFCs.
NASA Astrophysics Data System (ADS)
Lai, Yi-Chen; Ho, Hsin-Chia; Shih, Bo-Wei; Tsai, Feng-Yu; Hsueh, Chun-Hway
2018-05-01
Surface-enhanced Raman scattering (SERS) substrate with a higher surface area, enhanced light harvesting, multiple hot spots and strong electromagnetic field enhancements would exhibit enhanced Raman signals. Herein, the Ag nanoparticle/ZnO nanowire heterostructure decorated periodic silicon nanotube (Ag@ZnO@SiNT) substrate was proposed and fabricated. The proposed structure employed as SERS-active substrate was examined, and the results showed both the high performance in terms of high sensitivity and good reproducibility. Furthermore, the Ag@ZnO@SiNT substrate demonstrated the self-cleaning performance through the photocatalytic degradation of probed molecules upon UV-irradiation. The results showed that the proposed nanostructure had high performance, good reproducibility and reusability, and it is a promising SERS-active substrate for molecular sensing and cleaning.
NASA Technical Reports Server (NTRS)
1997-01-01
Advanced Flexible Reusable Surface Insulation, developed by Ames Research Center, protects the Space Shuttle from the searing heat that engulfs it on reentry into the Earth's atmosphere. Initially integrated into the Space Shuttle by Rockwell International, production was transferred to Hi-Temp Insulation Inc. in 1974. Over the years, Hi-Temp has created many new technologies to meet the requirements of the Space Shuttle program. This expertise is also used commercially, including insulation blankets to cover aircrafts parts, fire barrier material to protect aircraft engine cowlings and aircraft rescue fire fighter suits. A Fire Protection Division has also been established, offering the first suit designed exclusively by and for aircraft rescue fire fighters. Hi-Temp is a supplier to the Los Angeles City Fire Department as well as other major U.S. civil and military fire departments.
SSME main combustion chamber life prediction
NASA Technical Reports Server (NTRS)
Cook, R. T.; Fryk, E. E.; Newell, J. F.
1983-01-01
Typically, low cycle fatigue life is a function of the cyclic strain range, the material properties, and the operating temperature. The reusable life is normally defined by the number of strain cycles that can be accrued before severe material degradation occurs. Reusable life is normally signified by the initiation or propagation of surface cracks. Hot-fire testing of channel wall combustors has shown significant mid-channel wall thinning or deformation during accrued cyclic testing. This phenomenon is termed cyclic-creep and appears to be significantly accelerated at elevated surface temperatures. This failure mode was analytically modelled. The cyclic life of the baseline SSME-MCC based on measured calorimeter heat transfer data, and the life sensitivity of local hot spots caused by injector effects were determined. Four life enhanced designs were assessed.
Airframe integration trade studies for a reusable launch vehicle
NASA Astrophysics Data System (ADS)
Dorsey, John T.; Wu, Chauncey; Rivers, Kevin; Martin, Carl; Smith, Russell
1999-01-01
Future launch vehicles must be lightweight, fully reusable and easily maintained if low-cost access to space is to be achieved. The goal of achieving an economically viable Single-Stage-to-Orbit (SSTO) Reusable Launch Vehicle (RLV) is not easily achieved and success will depend to a large extent on having an integrated and optimized total system. A series of trade studies were performed to meet three objectives. First, to provide structural weights and parametric weight equations as inputs to configuration-level trade studies. Second, to identify, assess and quantify major weight drivers for the RLV airframe. Third, using information on major weight drivers, and considering the RLV as an integrated thermal structure (composed of thrust structures, tanks, thermal protection system, insulation and control surfaces), identify and assess new and innovative approaches or concepts that have the potential for either reducing airframe weight, improving operability, and/or reducing cost.
A green, reusable SERS film with high sensitivity for in-situ detection of thiram in apple juice
NASA Astrophysics Data System (ADS)
Sun, Hongbao; Liu, Hai; Wu, Yiyong
2017-09-01
We report a green and reusable surface-enhanced Raman scattering (SERS) film based on PMMA/Ag NPs/graphene. By using this Raman substrate, the SERS signals of R6G were significantly enhanced reaching a minimum detectable concentration of 5 × 10-8 M, due to having lots of hot spots adhered backside to the exposed graphene. The SERS film can be used for in-situ monitoring of trace thiram in apple juice with a detection limit of 1 × 10-6 M (0.24 ppm), which is below the maximal residue limit (MRL) of 7 ppm in fruit prescribed by the U.S. Environmental Protection Agency (EPA). Furthermore, reusability studies show that the SERS film can be used repeatedly. In addition, the graphene-enhanced SERS technique shows great potential applications for the in-situ detection and identification of pesticide residues in environmental water, fruits and vegetables.
Airframe Integration Trade Studies for a Reusable Launch Vehicle
NASA Technical Reports Server (NTRS)
Dorsey, John T.; Wu, Chauncey; Rivers, Kevin; Martin, Carl; Smith, Russell
1999-01-01
Future launch vehicles must be lightweight, fully reusable and easily maintained if low-cost access to space is to be achieved. The goal of achieving an economically viable Single-Stage-to-Orbit (SSTO) Reusable Launch Vehicle (RLV) is not easily achieved and success will depend to a large extent on having an integrated and optimized total system. A series of trade studies were performed to meet three objectives. First, to provide structural weights and parametric weight equations as inputs to configuration-level trade studies. Second, to identify, assess and quantify major weight drivers for the RLV airframe. Third, using information on major weight drivers, and considering the RLV as an integrated thermal structure (composed of thrust structures, tanks, thermal protection system, insulation and control surfaces), identify and assess new and innovative approaches or concepts that have the potential for either reducing airframe weight, improving operability, and/or reducing cost.
NASA Technical Reports Server (NTRS)
Viger, Brent J.; Logan, Robert F.; Fink, Jeffrey E.
1992-01-01
Specially designed bag maintains helium atmosphere around large, low-temperature duct. Easy to install, durable, and reusable. Intended to prevent cryopumping occurring if air or nitrogen allowed to make contact with cold surface of duct.
Epifanio, Monica; Inguva, Saikumar; Kitching, Michael; Mosnier, Jean-Paul; Marsili, Enrico
2015-12-01
The attachment of electrochemically active microorganisms (EAM) on an electrode is determined by both the chemistry and topography of the electrode surface. Pre-treatment of the electrode surface by atmospheric air plasma introduces hydrophilic functional groups, thereby increasing cell attachment and electroactivity in short-term experiments. In this study, we use graphite and carbon felt electrodes to grow the model EAM Shewanella loihica PV-4 at oxidative potential (0.2 V vs. Ag/AgCl). Cell attachment and electroactivity are measured through electrodynamic methods. Atmospheric air plasma pre-treatment increases cell attachment and current output at graphite electrodes by 25%, while it improves the electroactivity of the carbon felt electrodes by 450%. Air plasma pre-treatment decreased the coulombic efficiency on both carbon felt and graphite electrodes by 60% and 80%, respectively. Microbially produced flavins adsorb preferentially at the graphite electrode, and air plasma pre-treatment results in lower flavin adsorption at both graphite and carbon felt electrodes. Results show that air plasma pre-treatment is a feasible option to increase current output in bioelectrochemical systems. Copyright © 2015 Elsevier B.V. All rights reserved.
Programmers manual for static and dynamic reusable surface insulation stresses (resist)
NASA Technical Reports Server (NTRS)
Ogilvie, P. L.; Levy, A.; Austin, F.; Ojalvo, I. U.
1974-01-01
Programming information for the RESIST program for the dynamic and thermal stress analysis of the space shuttle surface insulation is presented. The overall flow chart of the program, overlay chart, data set allocation, and subprogram calling sequence are given along with a brief description of the individual subprograms and typical subprogram output.
Performance of LI-1542 reusable surface insulation system in a hypersonic stream
NASA Technical Reports Server (NTRS)
Hunt, L. R.; Shideler, J. L.; Weinstein, I.
1976-01-01
The thermal and structural performance LI-1542 reusable surface insulation (RSI) tiles was investigated. The test panel was designed to represent part of the surface structure on a space shuttle orbiter fuselage along a 1250 K isotherm. Aerothermal tests were conducted at a free-stream Mach number of 6.6, a total temperature of 1820 K, Reynolds numbers of 2 millon and 5 million per meter, and dynamic pressures of 26 and 65 kPa. The RSI tiles demonstrated good thermal protection and structural integrity. High temperatures were caused by misalinement in tile height, offset the tile longitudinal alinement, and leakage around thermal seals when differential pressure existed across the panel. The damage tolerance of LI-1542 RSI appeared high. The tile coating crazed early in the test program, but this did not effect the tile integrity. Erosion of the tile edges occurred at forward-facing steps and at the ends of longitudinal gaps because of particle impacts and flow shear.
Performance of LI-1542 reusable surface insulation system in a hypersonic stream
NASA Technical Reports Server (NTRS)
Hunt, L. R.; Bohon, H. L.
1974-01-01
The thermal and structural performance of a large panel of LI-1542 reusable surface insulation tiles was determined by a series of cyclic heating tests using radiant lamps and aerothemal tests in the Langley 8-foot high-temperature structures tunnel. Aerothermal tests were conducted at a free-stream Mach number of 6.6, a total temperature of 1830 K, Reynolds numbers of 2.0 and 4,900,000 per meter, and dynamic pressures of 29 and 65 kPa. The results suggest that pressure gradients in gaps and flow impingement on the header walls at the end of longitudinal gaps are sources for increased gap heating. Temperatures higher than surface radiation equilibrium temperature were measured deep in gaps and at the header walls. Also, the damage tolerance of the LI-1542 tiles appears to be very high. Tile edge erosion rate was slow; could not be tolerated in a shuttle application. Tiles soaked with water and subjected to rapid depressurization and aerodynamic heating showed no visible evidence of damage.
NASA Technical Reports Server (NTRS)
Throckmorton, D. A.
1976-01-01
An experimental investigation is presented that was performed to determine the effect of a surface-to-gap wall temperature discontinuity on the heat transfer within space shuttle, reusable surface insulation, tile gaps submerged in a thick turbulent boundary layer. Heat-transfer measurements were obtained on a flat-plate, single-gap model submerged in a turbulent tunnel wall boundary layer at a nominal free-stream Mach number of 10.3 and free-stream Reynolds numbers per meter of 1.5 million, 3.3 million and 7.8 million. Surface-to-gap wall temperature discontinuities of varying degree were created by heating the surface of the model upstream of the instrumented gap. The sweep angle of the gap was varied between 0 deg and 60 deg; gap width and depth were held constant. A surface-to-gap wall temperature discontinuity (surface temperature greater than gap wall temperature) results in increased heat transfer to the near-surface portion of the gap, as compared with the heat transfer under isothermal conditions, while decreasing the heat transfer to the deeper portions of the gap. The nondimensionalized heat transfer to the near-surface portion of the gap is shown to decrease with increasing Reynolds number; in the deeper portion of the gap, the heat transfer increases with Reynolds number.
[Crisis in the valuation, emotional labor and occupational burnout among teachers of religion].
Lachowska, Bogusława; Starczewski, Karol
2015-01-01
This article presents an analysis of the relationship between the crisis of values and in the valuation, the strategy of emotional labor, and occupational burnout in the group of lay teachers of religion. In addition, the role of emotional labor as a mediator of the relationship between the crisis of values and burnout was analyzed. Three strategies of emotional labor were considered in the study: surface acting, deep acting, and expression of naturally felt emotions. The study was conducted in a group of 169 lay teachers of religion (males - 24%, females - 76%), using the Questionnaire for Investigating Crisis in Valuation developed by Oleś, the Maslach Burnout Inventory, and the Emotional Labour Scale developed by Diefendorff, Croyle and Gosserand. The crisis of values and in the valuation is an important factor responsible for occupational burnout in the group of lay teachers of religion. Surface acting and expression of naturally felt emotions mediate the relationship between crisis in the valuation and emotional exhaustion, depersonalization and lack of personal accomplishment. Surface acting increases, while the expression of naturally felt emotions decreases occupational burnout. Deep acting is not related with occupational burnout. It is justified to seek factors favoring the expression of naturally felt emotions, and also those reducing surface acting. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.
Pressure gradient effects on heat transfer to reusable surface insulation tile-array gaps
NASA Technical Reports Server (NTRS)
Throckmorton, D. A.
1975-01-01
An experimental investigation was performed to determine the effect of pressure gradient on the heat transfer within space shuttle reusable surface insulation (RSI) tile-array gaps under thick, turbulent boundary-layer conditions. Heat-transfer and pressure measurements were obtained on a curved array of full-scale simulated RSI tiles in a tunnel-wall boundary layer at a nominal free-stream Mach number and free-stream Reynolds numbers. Transverse pressure gradients of varying degree were induced over the model surface by rotating the curved array with respect to the flow. Definition of the tunnel-wall boundary-layer flow was obtained by measurement of boundary-layer pitot pressure profiles, wall pressure, and heat transfer. Flat-plate heat-transfer data were correlated and a method was derived for prediction of heat transfer to a smooth curved surface in the highly three-dimensional tunnel-wall boundary-layer flow. Pressure on the floor of the RSI tile-array gap followed the trends of the external surface pressure. Heat transfer to the surface immediately downstream of a transverse gap is higher than that for a smooth surface at the same location. Heating to the wall of a transverse gap, and immediately downstream of it, at its intersection with a longitudinal gap is significantly greater than that for the simple transverse gap.
Re-usable electrochemical glucose sensors integrated into a smartphone platform.
Bandodkar, Amay J; Imani, Somayeh; Nuñez-Flores, Rogelio; Kumar, Rajan; Wang, Chiyi; Mohan, A M Vinu; Wang, Joseph; Mercier, Patrick P
2018-03-15
This article demonstrates a new smartphone-based reusable glucose meter. The glucose meter includes a custom-built smartphone case that houses a permanent bare sensor strip, a stylus that is loaded with enzyme-carbon composite pellets, and sensor instrumentation circuits. A custom-designed Android-based software application was developed to enable easy and clear display of measured glucose concentration. A typical test involves the user loading the software, using the stylus to dispense an enzymatic pellet on top of the bare sensor strip affixed to the case, and then introducing the sample. The electronic module then acquires and wirelessly transmits the data to the application software to be displayed on the screen. The deployed pellet is then discarded to regain the fresh bare sensor surface. Such a unique working principle allows the system to overcome challenges faced by previously reported reusable sensors, such as enzyme degradation, leaching, and hysteresis effects. Studies reveal that the enzyme loaded in the pellets are stable for up to 8 months at ambient conditions, and generate reproducible sensor signals. The work illustrates the significance of the pellet-based sensing system towards realizing a reusable, point-of-care sensor that snugly fits around a smartphone and which does not face issues usually common to reusable sensors. The versatility of this system allows it to be easily modified to detect other analytes for application in a wide range of healthcare, environmental and defense domains. Copyright © 2017 Elsevier B.V. All rights reserved.
Antony, R; Suja Pon Mini, P S; Theodore David Manickam, S; Sanjeev, Ganesh; Mitu, Liviu; Balakumar, S
2015-01-01
Chitosan (a biopolymer) anchored Cu(II) and Ni(II) Schiff base complexes, [M(OIAC)Cl2] (M: Cu/Ni and OIAC: ([2-oxo-1H-indol-3-ylidene]amino)chitosan) were electron beam irradiated by different doses (100 Gy, 1 kGy and 10 kGy). The electron beam has shown potential impact on biopolymer's support, in detail chain linking and chain scissoring, as evidenced by viscosity studies, FT-IR and X-ray diffraction spectroscopic techniques. Due to these structural changes, thermal properties of the complexes were found to be changed. The surface of these heterogeneous complexes was also effectually altered by electron beam. As a consequence, pores and holes were created as probed by SEM technique. The catalytic activity of both non-irradiated and irradiated complexes was investigated in the aerobic oxidation of cyclohexane using hydrogen peroxide oxidant. The catalytic ability of the complexes was enhanced significantly after irradiation as the result of surface changes. The reusability of the complexes was also greatly affected because of the structural variations in polymeric support. In terms of both better catalytic activity along with the reusability, 1 kGy is suggested as the best dose to attain adequate increase in catalytic activity and good reusability. Copyright © 2015 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fu, Zhifeng; Shao, Guocheng; Wang, Jun
2011-04-01
A filter pillar-array microstructure was coupled with a pneumatic micro-valve to fabricate a reusable miniaturized beads-trapping/releasing flow cell, in which trapping and releasing beads can be conveniently realized by switching the micro-valve. This miniaturized device was suitable to construct automatic fluidic system for “renewable surface analysis”. The renewable surface strategy based on pneumatic micro-valve enabled capture of beads in beads chamber prior to each assay, and release of the used beads after the assay. Chemiluminescent competitive immunoassay of 3,5,6-trichloropyridinol (TCP) was performed as a model to demonstrate the application potential of this reusable miniaturized flow cell. The whole fluidic assaymore » process including beads trapping, immuno-binding, beads washing, beads releasing and signal collection could be completed in 10 min. Immunoassay of TCP using this miniaturized device showed a linear range of 0.20-70 ng/mL with a limit of detection of 0.080 ng/mL. The device had been successfully used for detection of TCP spiked in rat serum with average recovery of 97%. This investigation provides a rapid, sensitive, reusable, low-cost and automatic miniaturized device for solid-phase biochemical analysis for various purposes.« less
NASA Technical Reports Server (NTRS)
Galanter, S. A.
1975-01-01
A space shuttle high temperature reusable surface insulation (HRSI) tile array with a single missing or lost tile was exposed to a hot gas simulated reentry environment to investigate the heating conditions in and around the vicinity of the missing HRSI tile. Heat flux and pressure data for the lost tile condition were obtained by the use of a water cooled lost tile calibration model. The maximum aluminum substrate temperature obtained during the simulated reentry was 128 C (263 F). The lost tile calibration data indicated a maximum heat flux in the lost tile cavity region of 63 percent of the upstream reference value. This test was conducted at the Ames Research Center in the 20 MW semielliptical thermal protection system (TPS) pilot plasma arc test facility.
Xu, Yan; Wu, Qian; Shimatani, Yuji; Yamaguchi, Koji
2015-10-07
Due to the lack of regeneration methods, the reusability of nanofluidic chips is a significant technical challenge impeding the efficient and economic promotion of both fundamental research and practical applications on nanofluidics. Herein, a simple method for the total regeneration of glass nanofluidic chips was described. The method consists of sequential thermal treatment with six well-designed steps, which correspond to four sequential thermal and thermochemical decomposition processes, namely, dehydration, high-temperature redox chemical reaction, high-temperature gasification, and cooling. The method enabled the total regeneration of typical 'dead' glass nanofluidic chips by eliminating physically clogged nanoparticles in the nanochannels, removing chemically reacted organic matter on the glass surface and regenerating permanent functional surfaces of dissimilar materials localized in the nanochannels. The method provides a technical solution to significantly improve the reusability of glass nanofluidic chips and will be useful for the promotion and acceleration of research and applications on nanofluidics.
Scalable and reusable micro-bubble removal method to flatten large-area 2D materials
NASA Astrophysics Data System (ADS)
Pham, Phi H. Q.; Quach, Nhi V.; Li, Jinfeng; Burke, Peter J.
2018-04-01
Bubbles generated during electro-delamination and chemical etch during large-area two-dimensional (2D) material transfer has been shown to cause rippling, and consequently, results in tears and wrinkles in the transferred film. Here, we demonstrate a scalable and reusable method to remove surface adhered micro-bubbles by using hydrophobic surfaces modified by self-assembled monolayers (SAMs). Bubble removal allows the 2D film to flatten out and prevents the formation of defects. Electrical characterization was used to verify improved transfer quality and was confirmed by increased field-effect mobility and decreased sheet resistance. Raman spectroscopy was also used to validate enhanced electrical quality following transfer. The bubble removal method can be applied to an assortment of 2D materials using diverse hydrophobic SAM variants. Our studies can be integrated into large scale applications and will lead to improved large-area 2D electronics in general.
Detail view of the vertical stabilizer of the Orbiter Discovery ...
Detail view of the vertical stabilizer of the Orbiter Discovery looking at the two-piece rudder which is used to control the yaw position of orbiter on approach and landing in earth's atmosphere and upon landing the two-piece rudder splays open to both sides of the stabilizer to act as an air brake to help slow the craft to a stop. Note the thermal protection system components with the white Advanced Flexible Reusable Surface Insulation Blanket and the black High-temperature Reusable Surface Insulation tiles along the outer edges (HRSI tiles). The marks seen on the HRSI tiles are injection point marks and holes for the application of waterproofing material. This view was taken from a service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Detail view of the vertical stabilizer of the Orbiter Discovery ...
Detail view of the vertical stabilizer of the Orbiter Discovery Discovery showing the thermal protection system components with the white Advanced Flexible Reusable Surface Insulation (AFSI) Blanket and the black High-temperature Reusable Surface Insulation (HRSI) tiles along the outer edges . The marks seen on the HRSI tiles are injection point marks and holes for the application of waterproofing material. This view also a good detailed view of the two-piece rudder which is used to control the yaw position of orbiter on approach and landing in earth's atmosphere and upon landing the two-piece rudder splays open to both sides of the stabilizer to act as an air brake to help slow the craft to a stop. This view was taken from a service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
NASA Technical Reports Server (NTRS)
Lin, Yi; Bunker, Christopher E.; Fernandos, K. A. Shiral; Connell, John W.
2012-01-01
The impurity-free aqueous dispersions of boron nitride nanosheets (BNNS) allowed the facile preparation of silver (Ag) nanoparticle-decorated BNNS by chemical reduction of an Ag salt with hydrazine in the presence of BNNS. The resultant Ag-BNNS nanohybrids remained dispersed in water, allowing convenient subsequent solution processing. By using substrate transfer techniques, Ag-BNNS nanohybrid thin film coatings on quartz substrates were prepared and evaluated as reusable surface enhanced Raman spectroscopy (SERS) sensors that were robust against repeated solvent washing. In addition, because of the unique thermal oxidation-resistant properties of the BNNS, the sensor devices may be readily recycled by short-duration high temperature air oxidation to remove residual analyte molecules in repeated runs. The limiting factor associated with the thermal oxidation recycling process was the Ostwald ripening effect of Ag nanostructures.
NASA Astrophysics Data System (ADS)
Huang, Da; Freeley, Mark; Palma, Matteo
2017-03-01
We present a facile strategy of general applicability for the assembly of individual nanoscale moieties in array configurations with single-molecule control. Combining the programming ability of DNA as a scaffolding material with a one-step lithographic process, we demonstrate the patterning of single quantum dots (QDs) at predefined locations on silicon and transparent glass surfaces: as proof of concept, clusters of either one, two, or three QDs were assembled in highly uniform arrays with a 60 nm interdot spacing within each cluster. Notably, the platform developed is reusable after a simple cleaning process and can be designed to exhibit different geometrical arrangements.
Reusable Metallic Thermal Protection Systems Development
NASA Technical Reports Server (NTRS)
Blosser, Max L.; Martin, Carl J.; Daryabeigi, Kamran; Poteet, Carl C.
1998-01-01
Metallic thermal protection systems (TPS) are being developed to help meet the ambitious goals of future reusable launch vehicles. Recent metallic TPS development efforts at NASA Langley Research Center are described. Foil-gage metallic honeycomb coupons, representative of the outer surface of metallic TPS were subjected to low speed impact, hypervelocity impact, rain erosion, and subsequent arcjet exposure. TPS panels were subjected to thermal vacuum, acoustic, and hot gas flow testing. Results of the coupon and panel tests are presented. Experimental and analytical tools are being developed to characterize and improve internal insulations. Masses of metallic TPS and advanced ceramic tile and blanket TPS concepts are compared for a wide range of parameters.
Testing the Shuttle heat-protection armor
NASA Technical Reports Server (NTRS)
Strouhal, G.; Tillian, D. J.
1976-01-01
The article deals with the thermal protection system (TPS) designed to keep Space Shuttle structures at 350 F ratings over a wide range of temperatures encountered in orbit, but also during prelaunch, launch, deorbit and re-entry, landing and turnaround. The structure, function, fabrication, and bonding of various types of reusable surface insulation and composite materials are described. Test programs are developed for insulation, seals, and adhesion bonds; leak tests and acoustic fatigue tests are mentioned. Test facilities include arc jets, radiant heaters, furnaces, and heated tunnels. The certification tests to demonstrate TPS reusability, structural integrity, thermal performance, and endurance will include full-scale assembly tests and initial orbital flight tests.
Investigations into the Anti-Felting Properties of Sputtered Wool Using Plasma Treatment
NASA Astrophysics Data System (ADS)
M. Borghei, S.; Shahidi, S.; Ghoranneviss, M.; Abdolahi, Z.
2013-01-01
In this research the effects of mordant and plasma sputtering treatments on the crystallinity and morphological properties of wool fabrics were investigated. The felting behavior of the treated samples was also studied. We used madder as a natural dye and copper sulfate as a metal mordant. We also used copper as the electrode material in a DC magnetron plasma sputtering device. The anti-felting properties of the wool samples before and after dying was studied, and it was shown that the shrink resistance and anti-felting behavior of the wool had been significantly improved by the plasma sputtering treatment. In addition, the percentage of crystallinity and the size of the crystals were investigated using an X-ray diffractometer, and a scanning electron microscope was used for morphological analysis. The amount of copper particles on the surface of the mordanted and sputtered fabrics was studied using the energy dispersive X-ray (EDX) method, and the hydrophobic properties of the samples were examined using the water drop test. The results show that with plasma sputtering treatment, the hydrophobic properties of the surface of wool become super hydrophobic.
NASA Technical Reports Server (NTRS)
Bellomy-Ezell, Jenny; Farmer, Jeff; Breeding, Shawn; Spivey, Reggie
1999-01-01
Much of the material science gained in microgravity research requires processing a sample in a high performance furnace. One such furnace currently being designed is the Quench Module Insert (QMI). The Principle Investigators, for whom the furnace is proposed, require high temperature gradients in their cylindrical samples to achieve the science objectives. One of the components critical to achieving high sample axial temperature gradients in the Quench Module Insert is a high performance cold zone to extract the heat from the sample. This cold zone employs a compliant, sliding thermal interface based on a Vel-Therm felt. This felt provides a conductive path between the Sample Cartridge Assembly (SCA) exterior surface and the interior surface of the water cooled chill block while allowing movement of the sample relative to the chill block. The Vel-Therm felt is composed of long polymer-based fibers affixed to a thin flexible substrate layer. The fibers are oriented perpendicular to this substrate giving the felt the appearance of a velvet fabric. The Vel-Therm felt heat extraction capability was quantified in earlier tests performed in an inert gas environment. The current activity, described in this paper, is intended to characterize the extraction capability of Vel-Therm felt in a vacuum environment similar to the QMI environment. This testing is necessary to quantify the thermal performance of the Vel-Therm felt and the sensitivity of that performance to key variables. The data derived from these tests will be incorporated into the current thermal models to improve the quality of the models and reduce uncertainty of the analytical results. In addition, the data will be used to help select the appropriate Vel-Therm felt and set proper operating limits as well as assess the performance range of the furnace. The objective of this test is to measure the heat extraction rate of the Vel-Therm felt as specified by the effective heat transfer coefficient. Therefore, the test setup was designed to force the bulk of the heat transfer through the area where the Vel-Therm felt was applied. A heat source, consisting of a ceramic heating element encased in a Copper (Cu) housing is mounted on four isolated support rods. A 6-layer molybdenum radiation shield is used to insulate against heat loss from the heater and prevent heat exchange between the hot and cold sides of the test apparatus. The Vel-Therm felt is affixed to the surface of the cold sink, a water-cooled Cu chill block. An adjustable plate supports and isolates the cold sink from above and is used to control the amount of the deflection of the Vel- Therm when in contact with the Cu heating element housing. The primary means of establishing the power being conducted through the felt is to measure the energy being transferred to the water passing through the chill block. Analysis was performed to support the assumption that the source and sink surfaces were approximately isothermal under the specific test conditions. As a check on the amount of power passing through the felt, the power supplied to the heater was also measured. Thermocouples were strategically located throughout the test apparatus for measurement purposes. A bell jar was lowered over the assembly to impose vacuum conditions. Currently, variables tested have been fiber compression and fiber type and surface temperatures (both the hot and cold side temperatures are hypothesized to be important to the performance of the Vel-Therm.) Selected runs were repeated to ensure consistency and repeatability. Results obtained thus far reveal that Vel-Therm performance is significantly degraded by fibers being exposed to high compression. It also shows that performance is somewhat negatively impacted by previous compression, thereby, raising the question of repeatability. In addition, early results show a significant dependence on temperature. A computer aided mathematical analysis of the test setup is ongoing. The results will be correlated to actual results. The correlation will examine such details as parasitic loses, conduction down the power leads and many other concerns.
Evaluation of Thermal Control Coatings for Flexible Ceramic Thermal Protection Systems
NASA Technical Reports Server (NTRS)
Kourtides, Demetrius; Carroll, Carol; Smith, Dane; Guzinski, Mike; Marschall, Jochen; Pallix, Joan; Ridge, Jerry; Tran, Duoc
1997-01-01
This report summarizes the evaluation and testing of high emissivity protective coatings applied to flexible insulations for the Reusable Launch Vehicle technology program. Ceramic coatings were evaluated for their thermal properties, durability, and potential for reuse. One of the major goals was to determine the mechanism by which these coated blanket surfaces become brittle and try to modify the coatings to reduce or eliminate embrittlement. Coatings were prepared from colloidal silica with a small percentage of either SiC or SiB6 as the emissivity agent. These coatings are referred to as gray C-9 and protective ceramic coating (PCC), respectively. The colloidal solutions were either brushed or sprayed onto advanced flexible reusable surface insulation blankets. The blankets were instrumented with thermocouples and exposed to reentry heating conditions in the Ames Aeroheating Arc Jet Facility. Post-test samples were then characterized through impact testing, emissivity measurements, chemical analysis, and observation of changes in surface morphology. The results show that both coatings performed well in arc jet tests with backface temperatures slightly lower for the PCC coating than with gray C-9. Impact testing showed that the least extensive surface destruction was experienced on blankets with lower areal density coatings.
Fault-Tolerant and Reconfigurable Control of Unmanned Aerial Vehicles (UAVs)
2008-02-29
forces and moments are expressed as functions of angle of attack, sideslip angle, angular rates, and control surface deflection. L, M, and N are...invertible. As for matrix B, the control surfaces of the reusable launch vehicle are designed to control each axes angular rate of aircraft...literature as being invertible. As for matrix B, the control surfaces of the UAV are designed to control angular rate along each axis of the aircraft
Mullite Whiskers and Mullite-whisker Felt
NASA Technical Reports Server (NTRS)
Talmy, Inna G.; Haught, Deborah A.
1993-01-01
The Naval Surface Warfare Center has developed processes for the preparation of mullite (3(Al2O3)(dot)2(SiO2)) whiskers and mullite-whisker felt. Three patents on the technology were issued in 1990. The processes are based on chemical reactions between AlF3, Al2O3, and SiO2. The felt is formed in-situ during the processing of shaped powdered precursors. It consists of randomly oriented whiskers which are mutually intergrown forming a rigid structure. The microstructure and properties of the felt and size of the whiskers can be modified by varying the amount of Al2O3 in the starting mixture. Loose mullite whiskers can be used as a reinforcement for polymer-, metal-, and ceramic-matrix composites. The felt can be used as preforms for fabricating composite materials as well as for thermal insulation and high temperature, chemically stable filters for liquids (melts) and gases.
NASA Technical Reports Server (NTRS)
Throckmorton, D. A.
1975-01-01
An experimental investigation was performed to determine the effect of pressure gradient on the heat transfer to space shuttle reusable surface insulation (RSI) tile array gaps under thick, turbulent boundary layer conditions. Heat transfer and pressure measurements were obtained on a curved array of full-scale simulated RSI tiles in a tunnel wall boundary layer at a nominal freestream Mach number of 10.3 and freestream unit Reynolds numbers of 1.6, 3.3, and and 6.1 million per meter. Transverse pressure gradients were induced over the model surface by rotating the curved array with respect to the flow. Definition of the tunnel wall boundary layer flow was obtained by measurement of boundary layer pitot pressure profiles, and flat plate wall pressure and heat transfer. Flat plate wall heat transfer data were correlated and a method was derived for prediction of smooth, curved array heat transfer in the highly three-dimensional tunnel wall boundary layer flow and simulation of full-scale space shuttle vehicle pressure gradient levels was assessed.
Disposable biomedical electrode
NASA Technical Reports Server (NTRS)
Frost, J. D., Jr.; Hillman, C. E., Jr.
1977-01-01
Reusable recording cap equipped with compressible snap-on bioelectronic electrodes is worn by patient to allow remote monitoring of electroencephalogram and electro-oculogram waveforms. Electrodes can be attached to inside surface of stretch-textile cap at twelve monitoring positions and at one or two ground positions.
NASA Technical Reports Server (NTRS)
Jackson, L. R.; Dixon, S. C.
1980-01-01
The design and assessment of reusable surface insulation (RSI), metallic stand off and multiwall thermal protection systems (TPS) is discussed. Multiwall TPS is described in some detail, and analyses useful for design of multiwall are included. Results indicate that multiwall has the potential to satisfy the TPS design goals better than the other systems. The total mass of the stand-off TPS and of the metallic systems require less primary structure mass than the RSI system, since the nonbuckling skin criteria required for RSI may be removed. Continued development of multiwall TPS is required to verify its potential and to provide the necessary data base for design.
Kim, Ki Jae; Lee, Heon Seong; Kim, Jeonghun; Park, Min-Sik; Kim, Jung Ho; Kim, Young-Jun; Skyllas-Kazacos, Maria
2016-06-08
A newly prepared type of carbon felt with oxygen-rich phosphate groups is proposed as a promising electrode with good stability for all-vanadium redox flow batteries (VRFBs). Through direct surface modification with ammonium hexafluorophosphate (NH4 PF6 ), phosphorus can be successfully incorporated onto the surface of the carbon felt by forming phosphate functional groups with -OH chemical moieties that exhibit good hydrophilicity. The electrochemical reactivity of the carbon felt toward the redox reactions of VO(2+) /VO2 (+) (in the catholyte) and V(3+) /V(2+) (in the anolyte) can be effectively improved owing to the superior catalytic effects of the oxygen-rich phosphate groups. Furthermore, undesirable hydrogen evolution can be suppressed by minimizing the overpotential for the V(3+) /V(2+) redox reaction in the anolyte of the VRFB. Cell-cycling tests with the catalyzed electrodes show improved energy efficiencies of 88.2 and 87.2 % in the 1(st) and 20(th) cycles compared with 83.0 and 81.1 %, respectively, for the pristine electrodes at a constant current density of 32 mA cm(-2) . These improvements are mainly attributed to the faster charge transfer allowed by the integration of the oxygen-rich phosphate groups on the carbon-felt electrode. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Stability and reactivity of dimethylethoxysilane
NASA Technical Reports Server (NTRS)
Johnson, Richard E.; Ford, Douglas I.
1992-01-01
Dimethylethoxysilane (DMES) is currently used to treat the High-temperature Reusable Surface Insulation (HRSI) shuttle tiles in order to provide a hydrophobic surface on the silica. DMES is a volatile, reactive silane that incorporates two reactive sites, the ethoxy group and the silica-hydride group. The work reported in this paper focused on the reactivity of these two groups with silica, water, quantitative reagents, and within DMES itself.
Effect of silicon carbide on devitrification of a glass coating for reusable surface insulation
NASA Technical Reports Server (NTRS)
Ransone, P. O.
1978-01-01
Devitrification (nucleation and growth of cristobalite) were investigated in the LI-0042 coating used for the space shuttle surface insulation. Excessive devitrification was found to be associated with the silicon carbide (SiC) constituent in the coating. Test results show that significant devitrification occurred only when SiC was present in the coating and when the thermal-exposure atmosphere was oxidizing.
Ansar, Siyam M.; Chakraborty, Saptarshi
2018-01-01
Mercaptoundecanoic acid (MUA) functionalized gold nanoparticles (AuNP-MUA) were synthesized and demonstrated to possess pH-triggered aggregation and re-dispersion, as well as the capability of phase transfer between aqueous and organic phases in response to changes in pH. The pH of aggregation for AuNP-MUA is consistent with the pKa of MUA (pH ~4) in solution, while AuNP-MUA phase transition between aqueous and organic phases occurs at pH ~9. The ion pair formation between the amine group in octadecylamine (ODA), the carboxylate group in MUA, and the hydrophobic alkyl chain of ODA facilitates the phase transfer of AuNP-MUA into an organic medium. The AuNP-MUA were investigated as a reusable catalyst in the catalytic reduction of 4-nitrophenol by borohydride—a model reaction for AuNPs. It was determined that 100% MUA surface coverage completely inhibits the catalytic activity of AuNPs. Decreasing the surface coverage was shown to increase catalytic activity, but this decrease also leads to decreased colloidal stability, recoverability, and reusability in subsequent reactions. At 60% MUA surface coverage, colloidal stability and catalytic activity were achieved, but the surface coverage was insufficient to enable redispersion following pH-induced recovery. A balance between AuNP colloidal stability, recoverability, and catalytic activity with reusability was achieved at 90% MUA surface coverage. The AuNP-MUA catalyst can also be recovered at different pH ranges depending on the recovery method employed. At pH ~4, protonation of the MUA results in reduced surface charge and aggregation. At pH ~9, ODA will form an ion-pair with the MUA and induce phase transfer into an immiscible organic phase. Both the pH-triggered aggregation/re-dispersion and aqueous/organic phase transfer methods were employed for catalyst recovery and reuse in subsequent reactions. The ability to recover and reuse the AuNP-MUA catalyst by two different methods and different pH regimes is significant, based on the fact that nanoparticle-catalyzed reactions may occur under different pH conditions. PMID:29772775
Wang, Shuangyin; Zhao, Xinsheng; Cochell, Thomas; Manthiram, Arumugam
2012-08-16
Nitrogen-doped carbon nanotubes have been grown, for the first time, on graphite felt (N-CNT/GF) by a chemical vapor deposition approach and examined as an advanced electrode for vanadium redox flow batteries (VRFBs). The unique porous structure and nitrogen doping of N-CNT/GF with increased surface area enhances the battery performance significantly. The enriched porous structure of N-CNTs on graphite felt could potentially facilitate the diffusion of electrolyte, while the N-doping could significantly contribute to the enhanced electrode performance. Specifically, the N-doping (i) modifies the electronic properties of CNT and thereby alters the chemisorption characteristics of the vanadium ions, (ii) generates defect sites that are electrochemically more active, (iii) increases the oxygen species on CNT surface, which is a key factor influencing the VRFB performance, and (iv) makes the N-CNT electrochemically more accessible than the CNT.
Testing of felt-ceramic materials for combustor applications
NASA Technical Reports Server (NTRS)
Venkat, R. S.; Roffe, G.
1983-01-01
The feasibility of using composite felt ceramic materials as combustor liners was experimentally studied. The material consists of a porous felt pad sandwiched between a layer of ceramic and one of solid metal. Flat, rectangular test panels, which encompassed several design variations of the basic composite material, were tested, two at a time, in a premixed gas turbine combustor as sections of the combustor wall. Tests were conducted at combustor inlet conditions of 0.5 MPa and 533 K with a reference velocity of 25 m/s. The panels were subjected to a hot gas temperature of 2170 K with 1% of the total airflow used to film cool the ceramic surface of the test panel. In general, thin ceramic layers yield low ceramic stress levels with high felt ceramic interface temperatures. On the other hand, thick ceramic layers result in low felt ceramic interface temperatures but high ceramic stress levels. Extensive thermal cycling appears to cause material degradation, but for a limited number of cycles, the survivability of felt ceramic materials, even under extremely severe combustor operating conditions, was conclusively demonstrated.
NASA Technical Reports Server (NTRS)
Leger, L. J. (Inventor)
1978-01-01
An improved isolation system is provided for attaching ceramic tiles of insulating material to the surface of a structure to be protected against extreme temperatures of the nature expected to be encountered by the space shuttle orbiter. This system isolates the fragile ceramic tiles from thermally and mechanically induced vehicle structural strains. The insulating tiles are affixed to a felt isolation pad formed of closely arranged and randomly oriented fibers by means of a flexible adhesive and in turn the felt pad is affixed to the metallic vehicle structure by an additional layer of flexible adhesive.
Measuring the size of an earthquake
Spence, W.
1977-01-01
Earthquakes occur in a broad range of sizes. A rock burst in an Idaho silver mine may involve the fracture of 1 meter of rock; the 1965 Rat island earthquake in the Aleutian arc involved a 650-kilometer lenght of Earth's crust. Earthquakes can be even smaller and even larger. if an earthquake is felt or causes perceptible surface damage, then its intesnity of shaking can be subjectively estimated. But many large earthquakes occur in oceanic area or at great focal depths. These are either simply not felt or their felt pattern does not really indicate their true size.
A reusable PZT transducer for monitoring initial hydration and structural health of concrete.
Yang, Yaowen; Divsholi, Bahador Sabet; Soh, Chee Kiong
2010-01-01
During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use.
A Reusable PZT Transducer for Monitoring Initial Hydration and Structural Health of Concrete
Yang, Yaowen; Divsholi, Bahador Sabet; Soh, Chee Kiong
2010-01-01
During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use. PMID:22399929
Lee, Hae Won; Kang, Dong-Ho; Cho, Jeong Ho; Lee, Sungjoo; Jun, Dong-Hwan; Park, Jin-Hong
2018-05-30
In recent years when the demand for high-performance biosensors has been aroused, a field-effect transistor (FET)-type biosensor (BioFET) has attracted great interest because of its high sensitivity, label-free detection, fast detection speed, and miniaturization. However, the insulating membrane in the conventional BioFET, which is essential in preventing the surface dangling bonds of typical semiconductors from nonspecific bindings, has limited the sensitivity of biosensors. Here, we present a highly sensitive and reusable membraneless BioFET based on a defect-free van der Waals material, tungsten diselenide (WSe 2 ). We intentionally generated a few surface defects that serve as extra binding sites for the bioreceptor immobilization through weak oxygen plasma treatment, consequently magnifying the sensitivity values to 2.87 × 10 5 A/A for 10 mM glucose. The WSe 2 BioFET also maintained its high sensitivity even after several cycles of rinsing and glucose application were repeated.
Metal-wool heat shields for space shuttle. [design, fabrication, and attachment to structure
NASA Technical Reports Server (NTRS)
Miller, R. C.; Clure, J. L.
1974-01-01
The packaging of metal wool for reusable thermal heat shields applied to aerodynamic and other surfaces for the space shuttle was analyzed and designed, and samples were fabricated and experimentally studied. Parametric trends were prepared for selected configurations. An all-metal thermally efficient, reliable, reusable and producible heat shield system was designed and structurally tested for use on spacecraft aerodynamic surfaces where temperatures do not exceed 810 K. Stainless steel sheet, primarily for structure and secondarily in the transverse plane for thermal expansion, was shown to accommodate thermal expansion in all directions when restrained at the edges and heated to 1360 K. Aerodynamic loads of 0.35 x 1000,000 newtons/sq meter, and higher, may be easily accepted by structures of this design. Seven all-metal thermal protection specimens, 12.7 cm square and 2.5 cm thick were fabricated and are being experimentally evaluated at simulated shuttle entry conditions in an arc jet facility.
Comparison of kinetic models for atom recombination on high-temperature reusable surface insulation
NASA Technical Reports Server (NTRS)
Willey, Ronald J.
1993-01-01
Five kinetic models are compared for their ability to predict recombination coefficients for oxygen and nitrogen atoms over high-temperature reusable surface insulation (HRSI). Four of the models are derived using Rideal-Eley or Langmuir-Hinshelwood catalytic mechanisms to describe the reaction sequence. The fifth model is an empirical expression that offers certain features unattainable through mechanistic description. The results showed that a four-parameter model, with temperature as the only variable, works best with data currently available. The model describes recombination coefficients for oxygen and nitrogen atoms for temperatures from 300 to 1800 K. Kinetic models, with atom concentrations, demonstrate the influence of atom concentration on recombination coefficients. These models can be used for the prediction of heating rates due to catalytic recombination during re-entry or aerobraking maneuvers. The work further demonstrates a requirement for more recombination experiments in the temperature ranges of 300-1000 K, and 1500-1850 K, with deliberate concentration variation to verify model requirements.
NASA Technical Reports Server (NTRS)
Smitherman, David; Woodcock, Gordon
2012-01-01
A space transportation infrastructure is described that utilizes the Space Launch System (SLS), the Mulit-Purpose Crew Vehicle (MPCV), the International Space Station (ISS), and propellant depot servicing platforms to support all foreseeable missions in the Earth-Moon vicinity and deep space out to Mars. The infrastructure utilizes current expendable launch vehicle (ELV) systems such as the Delta IV Heavy, Atlas V, and Falcon 9, for commercial crew, cargo, and propellant launches to a Low-Earth-Orbit (LEO) Depot and/or the ISS. The SLS provides all payload and propellant launches to the Earth-Moon Langrange Point 1 (EML1) Depot to support new reusable in-space transportation vehicles. The ISS or follow-on LEO Depot supports missions to Geosynchronous Earth Orbit (GEO) for satellite servicing and to Earth-Moon L1 for EML1 Depot missions. The EML1 Depot supports Lunar, Earth-Sun L2 (ESL2), Asteroid, and Mars missions. New vehicle design concepts are presented that can be launched utilizing the SLS and current ELV systems. These new reusable vehicle concepts include a Crew Transfer Vehicle (CTV) derived from the MPCV and a reusable Cryogenic Propulsion Stage (CPS) for crew transportation between the LEO Depot, EML1 Depot and missions beyond the Earth-Moon vicinity; a new reusable Lunar Lander for crew transportation between the EML1 Depot and the lunar surface; and a new reusable Deep Space Habitat (DSH) with a CTV to support crew missions from the EML1 Depot to ESL2, Asteroids, and a Mars Orbital Depot. The LEO Depot, EML1 Depot, and Mars Orbital Depot are based on International Space Station (ISS) heritage hardware. Data provided includes the number of launches required for each mission utilizing SLS and current ELV systems (Delta IV Heavy or equivalent) and the approximate vehicle masses and propellant requirements. Also included is a discussion on affordability with ideas on technologies that could reduce the number of launches required and thoughts on how this infrastructure might be implemented incrementally over the next few decades. The potential benefits of this infrastructure include competitive bidding for ELV flights and propellant services, development of new reusable in-space vehicles, and development of a robust multiuse infrastructure that can support many government and commercial missions simultaneously.
Mechanical Attachment of Reusable Surface Insulation to Space Shuttle Primary Structure
NASA Technical Reports Server (NTRS)
Fleck, R. W.; Lehman, J. K.
1973-01-01
Three methods of attaching surface insulation tiles to shuttle primary structure have been proposed: direct bond, mechanical attachment, and subpanels with standoffs. The direct bond approach is lightweight but is difficult to refurbish and inspect. The subpanel approach is heavier but allows for easy refurbishment since subpanels are easily removed and replaced. The mechanical attachment approach allows easy refurbishment and inspection and is lightweight when an efficient insulator is used between surface insulation tiles and primary structure.
16 CFR 1611.31 - Terms defined.
Code of Federal Regulations, 2011 CFR
2011-01-01
..., which is woven, knitted, felted or otherwise produced from any natural or man-made fiber, or substitute... include those fabrics having fancy woven, knitted or flock printed surfaces. (h) The term raised surface...
Vertical Landing Aerodynamics of Reusable Rocket Vehicle
NASA Astrophysics Data System (ADS)
Nonaka, Satoshi; Nishida, Hiroyuki; Kato, Hiroyuki; Ogawa, Hiroyuki; Inatani, Yoshifumi
The aerodynamic characteristics of a vertical landing rocket are affected by its engine plume in the landing phase. The influences of interaction of the engine plume with the freestream around the vehicle on the aerodynamic characteristics are studied experimentally aiming to realize safe landing of the vertical landing rocket. The aerodynamic forces and surface pressure distributions are measured using a scaled model of a reusable rocket vehicle in low-speed wind tunnels. The flow field around the vehicle model is visualized using the particle image velocimetry (PIV) method. Results show that the aerodynamic characteristics, such as the drag force and pitching moment, are strongly affected by the change in the base pressure distributions and reattachment of a separation flow around the vehicle.
NASA Astrophysics Data System (ADS)
Liu, Ying; Zhang, Kun; Yin, Xiaoshuang; Yang, Wenzhong; Zhu, Hongjun
2016-04-01
The metal-deposited magnetic catalyst microspheres (MCM-MPs) were successfully synthesized by one facile, high yield and controllable approach. Here, the bare magnetic microspheres were firstly synthesized according to the solvothermal method. Then silica shell were coated on the surface of the magnetic microspheres via sol-gel method, and subsequently with surface modifying with amino in the purpose to form SiO2-NH2 shell. Thus, metal particles were easily adsorbed into the SiO2-NH2 shell and in-situ reduced by NaBH4 solution. All the obtained products (MCM-Cu, MCM-Ag, MCM-Pd) which were monodisperse and constitutionally stable were exhibited high magnetization and excellent catalytic activity towards dyes solution reduction. The catalytic rate ratio of MCM-Pd: MCM-Cu: MCM-Ag could be 10:3:1. Besides, some special coordination compound Cu2(OH)3Br had been generated in the in-situ reduced process of MCM-Cu, which produced superior cyclical stability (>20 times) than that of MCM-Ag and MCM-Pd. In all, those highly reusability and great catalytic efficiency of MCM-MPs show promising and great potential for treatment of dye-contaminated water.
Performance of a mullite reusable surface insulation system in a hypersonic stream
NASA Technical Reports Server (NTRS)
Hunt, L. R.
1976-01-01
The thermal and structural performance of a large panel of mullite reusable surface insulation (RSI) tiles was determined by a series of aerothermal tests in the Langley 8-foot high-temperature structures tunnel. The test panel was designed to represent a portion of the surface structure on a space shuttle orbiter fuselage along a 1,150 K isotherm with the mullite tile system bonded directly to the primary structure. Aerothermal tests were conducted at a free-stream Mach number of 6.7, a total temperature of 1,880 K, a unit Reynolds number of 4.6 million per meter, and dynamic pressure of 62 kPa. The thermal response of the mullite tile was as predicted, and the bond-line temperature did not exceed the design level of 570 K during a typical entry-heat cycle. Geometric irregularities of the tile gaps affected the tile edge temperatures when exposed to hypersonic flow. The tile coating demonstrated good toughness to particle impacts, but the coating cracked and flaked with thermal cycles. The gap filler of woven silica fibers appeared to hinder flow penetration into the gaps and withstood the flow shear of the present tests.
A Framework for Assessing the Reusability of Hardware (Reusable Rocket Engines)
NASA Technical Reports Server (NTRS)
Childress-Thompson, Rhonda; Thomas, Dale; Farrington, Philip
2016-01-01
Within the past few years, there has been a renewed interest in reusability as it applies to space flight hardware. Commercial companies such as Space Exploration Technologies Corporation (SpaceX), Blue Origin, and United Launch Alliance (ULA) are pursuing reusable hardware. Even foreign companies are pursuing this option. The Indian Space Research Organization (ISRO) launched a reusable space plane technology demonstrator and Airbus Defense and Space is planning to recover the main engines and avionics from its Advanced Expendable Launcher with Innovative engine Economy [1] [2]. To date, the Space Shuttle remains as the only Reusable Launch (RLV) to have flown repeated missions and the Space Shutte Main Engine (SSME) is the only demonstrated reusable engine. Whether the hardware being considered for reuse is a launch vehicle (fully reusable), a first stage (partially reusable), or a booster engine (single component), the overall governing process is the same; it must be recovered and recertified for flight. Therefore, there is a need to identify the key factors in determining the reusability of flight hardware. This paper begins with defining reusability to set the context, addresses the significance of reuse, and discusses areas that limit successful implementation. Finally, this research identifies the factors that should be considered when incorporating reuse.
Code of Federal Regulations, 2010 CFR
2010-07-01
... content of less than 19.5 percent or greater than 23 percent. Intermodal container means a reusable cargo... does not include ship shaped or deep draft barges. Bulling means the horizontal dragging of cargo across a surface with none of the weight of the cargo supported by the fall. Danger zone means any place...
Code of Federal Regulations, 2013 CFR
2013-07-01
... content of less than 19.5 percent or greater than 23 percent. Intermodal container means a reusable cargo... does not include ship shaped or deep draft barges. Bulling means the horizontal dragging of cargo across a surface with none of the weight of the cargo supported by the fall. Danger zone means any place...
Code of Federal Regulations, 2014 CFR
2014-07-01
... content of less than 19.5 percent or greater than 23 percent. Intermodal container means a reusable cargo... does not include ship shaped or deep draft barges. Bulling means the horizontal dragging of cargo across a surface with none of the weight of the cargo supported by the fall. Danger zone means any place...
NASA Astrophysics Data System (ADS)
Langner, J.; Bruns, M.; Dixon, D.; Nefedov, A.; Wöll, Ch.; Scheiba, F.; Ehrenberg, H.; Roth, C.; Melke, J.
2016-07-01
Carbon felt electrodes for vanadium redox flow batteries are obtained by the graphitization of polyacrylonitrile based felts at different temperatures. Subsequently, the surface of the felts is modified via thermal oxidation at various temperatures. A single-cell experiment shows that the voltage efficiency is increased by this treatment. Electrode potentials measured with reference electrode setup show that this voltage efficiency increase is caused mainly by a reduction of the overpotential of the negative half-cell reaction. Consequently, this reaction is investigated further by cyclic voltammetry and the electrode activity is correlated with structural and surface chemical properties of the carbon fibers. By Raman, X-ray photoelectron and near edge X-ray absorption fine structure spectroscopy the role of edge sites and oxygen containing functional groups (OCFs) for the electrochemical activity are elucidated. A significant activity increase is observed in correlation with these two characteristics. The amount of OCFs is correlated with structural defects (e.g. edge sites) of the carbon fibers and therefore decreases with an increasing graphitization degree. Thus, for the same thermal oxidation temperature carbon fibers graphitized at a lower temperature show higher activities than those graphitized at a higher temperature.
2013-03-31
found to not thermally accommodate to the surface, rather they leave in excited vibrational levels. The new finite-rate model and thermal accommodation...vehicle’s thermal protection system (TPS). Many TPS materials act as a catalyst for the heterogeneous recombination of dissociated species back into...it is a significant component in both reusable (LI900, LI2200, FRSI) and ablative (SIRCA) thermal protection systems [24]. In addition, studies have
NASA Astrophysics Data System (ADS)
Chandwani, Nisha; Dave, Purvi; Jain, Vishal; Nema, Sudhir; Mukherjee, Subroto
2017-04-01
The present work investigates the effect of high frequency (2.5 MHz) Dielectric Barrier Discharge (DBD) in air on surface characteristics of Merino wool as a function of plasma exposure time (5s to 15s). The FE-SEM (Field Emission Scanning Electron Microscopy), EDS (Energy Dispersive X-ray spectrum) and Derivative ATR-FTIR (Attenuated Total Reflection- Fourier Transform Infrared) Spectroscopy are used to study physio-chemical changes induced by plasma. These physio-chemical properties of fibers can be co-related with the felting behaviour of the wool fiber, which leads to shrinkage and pilling of garments while laundering. Felting occurs mainly because of presence of outermost hydrophobic cuticle layer having sharp scales. The FE-SEM analysis of wool fiber surface reveals that cuticle scales on wool fiber become blunt after plasma processing. The ATR-FTIR analysis along with second order derivative spectroscopy demonstrates the cleavage of di-sulphide bonds of cuticle and formation of sulphur-oxygen groups such as Cystine Sulphonate (-S-SO3-), cysteic acid (-SO3-), cystine monoxide(-SO-S-), cysteine di-oxide (-SO2-S-). A possible explanation about how the combined effect of morphological and chemical changes induced by plasma results in minimizing the felting of wool fibers is discussed.
NASA Technical Reports Server (NTRS)
Milhoan, James D.; Pham, Vuong T.; Sherborne, William D.
1993-01-01
Thermal tests of Orbiter thermal protection system (TPS) tiles, which were coated with borosilicate glass slurries fabricated at Kennedy Space Center (KSC), were performed in the Radiant Heat Test Facility and the Atmospheric Reentry Materials & Structures Evaluation Facility at Johnson Space Center to verify tile coating integrity after exposure to multiple entry simulation cycles in both radiant and convective heating environments. Eight high temperature reusable surface insulation (HRSI) tiles and six low temperature reusable surface insulation (LRSI) tiles were subjected to 25 cycles of radiant heat at peaked surface temperatures of 2300 F and 1200 F, respectively. For the LRSI tiles, an additional cycle at peaked surface temperature of 2100 F was performed. There was no coating crack on any of the HRSI specimens. However, there were eight small coating cracks (less than 2 inches long) on two of the six LRSI tiles on the 26th cycle. There was practically no change on the surface reflectivity, physical dimensions, or weight of any of the test specimens. There was no observable thermal-chemical degradation of the coating either. For the convective heat test, eight HRSI tiles were tested for five cycles at a surface temperature of 2300 F. There was no thermal-induced coating crack on any of the test specimens, almost no change on the surface reflectivity, and no observable thermal-chemical degradation with an exception of minor slumping of the coating under painted TPS identification numbers. The tests demonstrated that KSC's TPS slurries and coating processes meet the Orbiter's thermal specification requirements.
Adherence of Myxobolus cerebralis myxospores to waders: Implications for disease dissemination
Gates, K.K.; Guy, C.S.; Zale, A.V.; Horton, T.B.
2008-01-01
The vectors involved in the spread of whirling disease, which is caused by Myxobolus cerebralis, are only partly understood. However, the parasite has rapidly become established in many regions, suggesting that it is easily disseminated. We gained insight into transport vectors by examining the surface porosity of common wading equipment materials and the adherence of M. cerebralis myxospores to them. Interstitial spaces within rubber, felt, lightweight nylon, and neoprene were measured on scanning electron microscope images. Myxospores were applied to each material, the material was rinsed, and the myxospores recovered to assess adherence. The mean interstitial space size of rubber was the smallest (2.0 ??m), whereas that of felt was the largest (31.3 ??m). The highest recovery rates were from rubber and the glass control. Percent myxospore recovery varied by material, the recovery from felt being lower than that from all other materials. The potential for felt to carry even small numbers of myxospores suggests that the introduction of M. cerebralis by felt-soled wading boots is possible. ?? Copyright by the American Fisheries Society 2008.
Development of Advanced Conformal Ablative TPS Fabricated from Rayon- and PAN-Based Carbon Felts
NASA Technical Reports Server (NTRS)
Gasch, Matthew; Stackpoole, Margaret; White, Susan; Boghozian, Tane
2016-01-01
The conformal ablative TPS first developed under NASA's Hypersonics Project in the early 2000's demonstrated very low through the thickness conductivity compared to state-ofthe- art PICA. However, in initial arcjet testing of Conformal-1, surface recession rates were 2x higher than PICA. Because commercial carbon felts are currently available as very thin substrates, this was a concern if conformal TPS were to be considered for a mission that required thicker material. Discussed in this paper are the results of the development of an Advanced Conformal TPS derived from thicker, higher density carbon felt. Two substrate systems were evaluated, the first material was a needled rayon-based carbon felt and the other a needled PAN-based carbon felt. Both substrates were impregnated with phenolic resin following the PICA/CPICA process to add a low density phenolic matrix to the system prior to aerothermal screening at the LaRC HyMETS facility and larger scale testing in the NASA ARC Interaction Heating Facility (IHF) at heating fluxes ranging from 250-1700 W/cm2.
Study of structural active cooling and heat sink systems for space shuttle
NASA Technical Reports Server (NTRS)
1972-01-01
This technology investigation was conducted to evaluate the feasibility of a number of thermal protection systems (TPS) concepts which are alternate candidates to the space shuttle baseline TPS. Four independent tasks were performed. Task 1 consisted of an in-depth evaluation of active structural cooling of the space shuttle orbiter. In Task 2, heat sink concepts for the booster were studied to identify and postulate solutions for design problems unique to heat sink TPS. Task 3 consisted of a feasibility demonstration test of a phase change material (PCM) incorporated into a reusable surface insulation (RSI) thermal protection system for the shuttle orbiter. In Task 4 the feasibility of heat pipes for stagnation region cooling was studied for the booster and the orbiter. Designs were developed for the orbiter leading edge and used in trade studies of leading edge concepts. At the time this program was initiated, a 2-stage fully reusable shuttle system was envisioned; therefore, the majority of the tasks were focused on the fully reusable system environments. Subsequently, a number of alternate shuttle system approaches, with potential for reduced shuttle system development funding requirements, were proposed. Where practicable, appropriate shifts in emphasis and task scoping were made to reflect these changes.
Development of Metallic Thermal Protection Systems for the Reusable Launch Vehicle
NASA Technical Reports Server (NTRS)
Blosser, Max L.
1996-01-01
A reusable Thermal Protection System (TPS) that is not only lightweight, but durable, operable and cost effective is one of the technologies required by the Reusable Launch Vehicle (RLV) to achieve the goal of drastically reducing the cost of delivering payload to orbit. Metallic TPS is one of the systems being developed to meet this challenge. Current efforts involve improving the superalloy honeycomb TPS concept, which consists of a foil-gage metallic box encapsulating a low density fibrous insulation, and evaluating it for RLV requirements. The superalloy honeycomb TPS concept is mechanically attached to the vehicle structure. Improvements include more efficient internal insulation, a simpler, lighter weight configuration, and a quick-release fastener system for easier installation and removal. Evaluation includes thermal and structural analysis, fabrication and testing of both coupons and TPS panels under conditions simulating RLV environments. Coupons of metallic honeycomb sandwich, representative of the outer TPS surface, were subjected to low speed impact, hypervelocity impact, and rain erosion testing as well as subsequent arcjet exposure. Arrays of TPS panels have been subjected to radiant heating in a thermal/vacuum facility, aerodynamic heating in an arcjet facility and acoustic loading.
Saleem, Muhammad; Rafiq, Muhammad; Seo, Sung-Yum; Lee, Ki Hwan
2016-02-02
A successful prescription is presented for acetylcholinesterase physically adsorbed on to a mesoporous silicon surface, with a promising hydrolytic response towards acetylthiocholine iodide. The catalytic behaviour of the immobilized enzyme was assessed by spectrophotometric bioassay using neostigmine methyl sulfate as a standard acetycholinesterase inhibitor. The surface modification was studied through field emission SEM, Fourier transform IR spectroscopy, energy-dispersive X-ray spectroscopy, cathode luminescence and X-ray photoelectron spectroscopy analysis, photoluminescence measurement and spectrophotometric bioassay. The porous silicon-immobilized enzyme not only yielded greater enzyme stability, but also significantly improved the native photoluminescence at room temperature of the bare porous silicon architecture. The results indicated the promising catalytic behaviour of immobilized enzyme compared with that of its free counterpart, with a greater stability, and that it aided reusability and easy separation from the reaction mixture. The porous silicon-immobilized enzyme was found to retain 50% of its activity, promising thermal stability up to 90°C, reusability for up to three cycles, pH stability over a broad pH of 4-9 and a shelf-life of 44 days, with an optimal hydrolytic response towards acetylthiocholine iodide at variable drug concentrations. On the basis of these findings, it was believed that the porous silicon-immobilized enzyme could be exploited as a reusable biocatalyst and for screening of acetylcholinesterase inhibitors from crude plant extracts and synthesized organic compounds. Moreover, the immobilized enzyme could offer a great deal as a viable biocatalyst in bioprocessing for the chemical and pharmaceutical industries, and bioremediation to enhance productivity and robustness. © 2016 Authors.
Saleem, Muhammad; Rafiq, Muhammad; Seo, Sung-Yum; Lee, Ki Hwan
2016-01-01
A successful prescription is presented for acetylcholinesterase physically adsorbed on to a mesoporous silicon surface, with a promising hydrolytic response towards acetylthiocholine iodide. The catalytic behaviour of the immobilized enzyme was assessed by spectrophotometric bioassay using neostigmine methyl sulfate as a standard acetycholinesterase inhibitor. The surface modification was studied through field emission SEM, Fourier transform IR spectroscopy, energy-dispersive X-ray spectroscopy, cathode luminescence and X-ray photoelectron spectroscopy analysis, photoluminescence measurement and spectrophotometric bioassay. The porous silicon-immobilized enzyme not only yielded greater enzyme stability, but also significantly improved the native photoluminescence at room temperature of the bare porous silicon architecture. The results indicated the promising catalytic behaviour of immobilized enzyme compared with that of its free counterpart, with a greater stability, and that it aided reusability and easy separation from the reaction mixture. The porous silicon-immobilized enzyme was found to retain 50% of its activity, promising thermal stability up to 90°C, reusability for up to three cycles, pH stability over a broad pH of 4–9 and a shelf-life of 44 days, with an optimal hydrolytic response towards acetylthiocholine iodide at variable drug concentrations. On the basis of these findings, it was believed that the porous silicon-immobilized enzyme could be exploited as a reusable biocatalyst and for screening of acetylcholinesterase inhibitors from crude plant extracts and synthesized organic compounds. Moreover, the immobilized enzyme could offer a great deal as a viable biocatalyst in bioprocessing for the chemical and pharmaceutical industries, and bioremediation to enhance productivity and robustness. PMID:26839417
Development of a Pressure Box to Evaluate Reusable-Launch-Vehicle Cryogenic-Tank Panels
NASA Technical Reports Server (NTRS)
Ambur, Damodar R.; Sikora, Joseph; Maguire, James F.; Winn, Peter M.
1996-01-01
A cryogenic pressure-box test machine has been designed and is being developed to test full-scale reusable-launch-vehicle cryogenic-tank panels. This machine is equipped with an internal pressurization system, a cryogenic cooling system, and a heating system to simulate the mechanical and thermal loading conditions that are representative of a reusable-launch-vehicle mission profile. The cryogenic cooling system uses liquid helium and liquid nitrogen to simulate liquid hydrogen and liquid oxygen tank internal temperatures. A quartz lamp heating system is used for heating the external surface of the test panels to simulate cryogenic-tank external surface temperatures during re-entry of the launch vehicle. The pressurization system uses gaseous helium and is designed to be controlled independently of the cooling system. The tensile loads in the axial direction of the test panel are simulated by means of hydraulic actuators and a load control system. The hoop loads in the test panel are reacted by load-calibrated turnbuckles attached to the skin and frame elements of the test panel. The load distribution in the skin and frames can be adjusted to correspond to the tank structure by using these turnbuckles. The seal between the test panel and the cryogenic pressure box is made from a reinforced Teflon material which can withstand pressures greater than 52 psig at cryogenic temperatures. Analytical results and tests on prototype test components indicate that most of the cryogenic-tank loading conditions that occur in flight can be simulated in the cryogenic pressure-box test machine.
Parameter Validation for Evaluation of Spaceflight Hardware Reusability
NASA Technical Reports Server (NTRS)
Childress-Thompson, Rhonda; Dale, Thomas L.; Farrington, Phillip
2017-01-01
Within recent years, there has been an influx of companies around the world pursuing reusable systems for space flight. Much like NASA, many of these new entrants are learning that reusable systems are complex and difficult to acheive. For instance, in its first attempts to retrieve spaceflight hardware for future reuse, SpaceX unsuccessfully tried to land on a barge at sea, resulting in a crash-landing. As this new generation of launch developers continues to develop concepts for reusable systems, having a systematic approach for determining the most effective systems for reuse is paramount. Three factors that influence the effective implementation of reusability are cost, operability and reliability. Therefore, a method that integrates these factors into the decision-making process must be utilized to adequately determine whether hardware used in space flight should be reused or discarded. Previous research has identified seven features that contribute to the successful implementation of reusability for space flight applications, defined reusability for space flight applications, highlighted the importance of reusability, and presented areas that hinder successful implementation of reusability. The next step is to ensure that the list of reusability parameters previously identified is comprehensive, and any duplication is either removed or consolidated. The characteristics to judge the seven features as good indicators for successful reuse are identified and then assessed using multiattribute decision making. Next, discriminators in the form of metrics or descriptors are assigned to each parameter. This paper explains the approach used to evaluate these parameters, define the Measures of Effectiveness (MOE) for reusability, and quantify these parameters. Using the MOEs, each parameter is assessed for its contribution to the reusability of the hardware. Potential data sources needed to validate the approach will be identified.
14 CFR 437.23 - Program description.
Code of Federal Regulations, 2013 CFR
2013-01-01
... photographs of the reusable suborbital rocket; and (2) Gross liftoff weight and thrust profile of the reusable suborbital rocket. (b) An applicant must describe— (1) All reusable suborbital rocket systems, including any..., software and computing systems, avionics, and guidance systems used in the reusable suborbital rocket; (2...
14 CFR 437.23 - Program description.
Code of Federal Regulations, 2011 CFR
2011-01-01
... photographs of the reusable suborbital rocket; and (2) Gross liftoff weight and thrust profile of the reusable suborbital rocket. (b) An applicant must describe— (1) All reusable suborbital rocket systems, including any..., software and computing systems, avionics, and guidance systems used in the reusable suborbital rocket; (2...
14 CFR 437.23 - Program description.
Code of Federal Regulations, 2014 CFR
2014-01-01
... photographs of the reusable suborbital rocket; and (2) Gross liftoff weight and thrust profile of the reusable suborbital rocket. (b) An applicant must describe— (1) All reusable suborbital rocket systems, including any..., software and computing systems, avionics, and guidance systems used in the reusable suborbital rocket; (2...
14 CFR 437.23 - Program description.
Code of Federal Regulations, 2010 CFR
2010-01-01
... photographs of the reusable suborbital rocket; and (2) Gross liftoff weight and thrust profile of the reusable suborbital rocket. (b) An applicant must describe— (1) All reusable suborbital rocket systems, including any..., software and computing systems, avionics, and guidance systems used in the reusable suborbital rocket; (2...
14 CFR 437.23 - Program description.
Code of Federal Regulations, 2012 CFR
2012-01-01
... photographs of the reusable suborbital rocket; and (2) Gross liftoff weight and thrust profile of the reusable suborbital rocket. (b) An applicant must describe— (1) All reusable suborbital rocket systems, including any..., software and computing systems, avionics, and guidance systems used in the reusable suborbital rocket; (2...
2003-10-01
In the Orbiter Processing Facility, Harrell Watts (left), with United Space Alliance, removes a tile from the thermal barrier around the umbilical areas, the external tank attach points, on the underside of Atlantis. The umbilical areas are closed off after ET separation by a door, seen here. The exposed area of each closed door is covered with reusable surface insulation.
Improvements to the Whoosh Bottle Rocket Car Demonstration
ERIC Educational Resources Information Center
Campbell, Dean J.; Staiger, Felicia A.; Jujjavarapu, Chaitanya N.
2015-01-01
The whoosh bottle rocket car has been redesigned to be more reusable and more robust, making it even easier to use as a demonstration. Enhancements of this demonstration, including the use of heat sensitive ink and electronic temperature probes, enable users to find warmer and cooler regions on the surface of the whoosh bottle.
A semiconductor titania (TiO2) surface was modified by surfactant adsorption to make it more hydrophobic and to increase the adsorption of hydrophobic organic compounds (HOCs) and their photodegradation rates under UV irradiation. Photocatalytic experiments using Ti...
NASA Technical Reports Server (NTRS)
1991-01-01
Project UM-Haul is the preliminary design of a reusable lunar transportation vehicle that travels between a lunar parking orbit and the lunar surface. This vehicle is an indispensible link in the overall task of establishing a lunar base as defined by the NASA Space Exploration Initiative. The response to this need consists of two independent vehicles: a lander and an unloader. The system can navigate and unload itself with a minimum amount of human intervention. The design addresses structural analysis, propulsion, power, controls, communications, payload handling and orbital operations. The Lander has the capacity to decend from low lunar orbit (LLO) to the lunar surface carrying a 7000 kg payload, plus the unloader, plus propellant for ascent to LLO. The Lander employs the Unloader by way of a motorized ramp. The Unloader is a terrain vehicle capable of carrying cargoes of 8,500 kg mass and employs a lift system to lower payloads to the ground. The system can perform ten missions before requiring major servicing.
NASA Astrophysics Data System (ADS)
Li, Hui; Li, Yuzhuo; Li, Zhiping; Peng, Xiyang; Li, Yanan; Li, Gui; Tan, Xianzhou; Chen, Gongxi
2012-03-01
Preparation of berberine hydrochloride (B-Cl) imprinted polymers (MIPs) based on surface imprinting technique with silica gel as sacrificial support material was performed successfully by using B-Cl as template, methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) as functional monomer and cross-linker, respectively. The prepared polymers were characterized by Fourier transmission infrared spectrometry (FTIR) and scanning electron microscopy (SEM). Adsorption behavior of the MIPs for the template and its structural analogues was investigated. Sites distribution on the surface of MIPs was explored by using different isotherm adsorption models and thermodynamic parameters for the adsorption of B-Cl on the MIPs determined. Sample application and reusability for the MIPs was also evaluated. Results indicated the strong adsorption and high selectivity of the MIPs for B-Cl. Saturated adsorption capacity reached 27.2 μmol g-1 and the selectivity coefficient of the MIPs for B-Cl relative to jatrorrhizine hydrochloride (J-Cl) and palmatine palmatus hydrochloride (P-Cl) are 3.70 and 6.03, respectively. In addition, the MIPs were shown with good reusability and selectively retention ability in sample application.
Reusable software parts and the semi-abstract data type
NASA Technical Reports Server (NTRS)
Cohen, Sanford G.
1986-01-01
The development of reuable software parts has been an area of intense discussion within the software community for many years. An approach is described for developing reusable parts for the applications of missile guidance, navigation and control which meet the following criteria: (1) Reusable; (2) Tailorable; (3) Efficient; (4) Simple to use; and (5) Protected against misuse. Validating the feasibility of developing reusable parts which possess these characteristics is the basis of the Common Ada Missile Packages Program (CAMP). Under CAMP, over 200 reusable software parts were developed, including part for navigation, Kalman filter, signal processing and autopilot. Six different methods are presented for designing reusable software parts.
14 CFR 431.79 - Reusable launch vehicle mission reporting requirements.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Reusable launch vehicle mission reporting requirements. 431.79 Section 431.79 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION...-Licensing Requirements-Reusable Launch Vehicle Mission License Terms and Conditions § 431.79 Reusable launch...
14 CFR 431.79 - Reusable launch vehicle mission reporting requirements.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Reusable launch vehicle mission reporting requirements. 431.79 Section 431.79 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION...-Licensing Requirements-Reusable Launch Vehicle Mission License Terms and Conditions § 431.79 Reusable launch...
14 CFR 431.79 - Reusable launch vehicle mission reporting requirements.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Reusable launch vehicle mission reporting requirements. 431.79 Section 431.79 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION...-Licensing Requirements-Reusable Launch Vehicle Mission License Terms and Conditions § 431.79 Reusable launch...
14 CFR 431.79 - Reusable launch vehicle mission reporting requirements.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Reusable launch vehicle mission reporting requirements. 431.79 Section 431.79 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION...-Licensing Requirements-Reusable Launch Vehicle Mission License Terms and Conditions § 431.79 Reusable launch...
14 CFR 437.67 - Tracking a reusable suborbital rocket.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Tracking a reusable suborbital rocket. 437... a reusable suborbital rocket. A permittee must— (a) During permitted flight, measure in real time the position and velocity of its reusable suborbital rocket; and (b) Provide position and velocity...
14 CFR 437.67 - Tracking a reusable suborbital rocket.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Tracking a reusable suborbital rocket. 437... a reusable suborbital rocket. A permittee must— (a) During permitted flight, measure in real time the position and velocity of its reusable suborbital rocket; and (b) Provide position and velocity...
14 CFR 437.67 - Tracking a reusable suborbital rocket.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Tracking a reusable suborbital rocket. 437... a reusable suborbital rocket. A permittee must— (a) During permitted flight, measure in real time the position and velocity of its reusable suborbital rocket; and (b) Provide position and velocity...
14 CFR 437.67 - Tracking a reusable suborbital rocket.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Tracking a reusable suborbital rocket. 437... a reusable suborbital rocket. A permittee must— (a) During permitted flight, measure in real time the position and velocity of its reusable suborbital rocket; and (b) Provide position and velocity...
14 CFR 437.67 - Tracking a reusable suborbital rocket.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Tracking a reusable suborbital rocket. 437... a reusable suborbital rocket. A permittee must— (a) During permitted flight, measure in real time the position and velocity of its reusable suborbital rocket; and (b) Provide position and velocity...
Estimates Of The Orbiter RSI Thermal Protection System Thermal Reliability
NASA Technical Reports Server (NTRS)
Kolodziej, P.; Rasky, D. J.
2002-01-01
In support of the Space Shuttle Orbiter post-flight inspection, structure temperatures are recorded at selected positions on the windward, leeward, starboard and port surfaces. Statistical analysis of this flight data and a non-dimensional load interference (NDLI) method are used to estimate the thermal reliability at positions were reusable surface insulation (RSI) is installed. In this analysis, structure temperatures that exceed the design limit define the critical failure mode. At thirty-three positions the RSI thermal reliability is greater than 0.999999 for the missions studied. This is not the overall system level reliability of the thermal protection system installed on an Orbiter. The results from two Orbiters, OV-102 and OV-105, are in good agreement. The original RSI designs on the OV-102 Orbital Maneuvering System pods, which had low reliability, were significantly improved on OV-105. The NDLI method was also used to estimate thermal reliability from an assessment of TPS uncertainties that was completed shortly before the first Orbiter flight. Results fiom the flight data analysis and the pre-flight assessment agree at several positions near each other. The NDLI method is also effective for optimizing RSI designs to provide uniform thermal reliability on the acreage surface of reusable launch vehicles.
Saviello, Daniela; Trabace, Maddalena; Alyami, Abeer; Mirabile, Antonio; Giorgi, Rodorico; Baglioni, Piero; Iacopino, Daniela
2018-05-01
The development of protocols for the protection of the large patrimony of works of art created by felt tip pen media since the 1950's requires detailed knowledge of the main dyes constituting commercial ink mixtures. In this work Surface Enhanced Raman Scattering (SERS) and UV-vis spectroscopy were used for the first time for the systematic identification of dye composition in commercial felt tip pens. A large selection of pens comprising six colors of five different brands was analyzed. Intense SERS spectra were obtained for all colors, allowing identification of main dye constituents. Poinceau 4R and Eosin dyes were found to be the main constituents of red and pink colors; Rhodamine and Tartrazine were found in orange and yellow colors; Erioglaucine was found in green and blue colors. UV-vis analysis of the same inks was used to support SERS findings but also to unequivocally assign some uncertain dye identifications, especially for yellow and orange colors. The spectral data of all felt tip pens collected through this work were assembled in a database format. The data obtained through this systematic investigation constitute the basis for the assembly of larger reference databases that ultimately will support the development of conservation protocols for the long term preservation of modern art collections. Copyright © 2018 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Norman, I.; Rochelle, W. C.; Kimbrough, B. S.; Ritrivi, C. A.; Ting, P. C.; Dotts, R. L.
1982-01-01
Thermal performance verification of Reusable Surface Insulation (RSI) has been accomplished by comparisons of STS-2 Orbiter Flight Test (OFT) data with Thermal Math Model (TMM) predictions. The OFT data was obtained from Development Flight Instrumentation RSI plug and gap thermocouples. Quartertile RSI TMMs were developed using measured flight data for surface temperature and pressure environments. Reference surface heating rates, derived from surface temperature data, were multiplied by gap heating ratios to obtain tile sidewall heating rates. This TMM analysis resulted in good agreement of predicted temperatures with flight data for thermocouples located in the RSI, Strain Isolation Pad, filler bar and structure.
Liu, Wanting; Su, Qing; Ju, Pengyao; Guo, Bixuan; Zhou, Hui; Li, Guanghua; Wu, Qiaolin
2017-02-22
A hydrazone-based covalent organic framework (COF) was synthesized by condensation of 2,5-dimethoxyterephthalohydrazide with 1,3,5-triformylbenzene under solvothermal conditions. The COF material exhibits excellent porosity with a BET surface area of up to 1501 m 2 g -1 , high crystallinity, and good thermal and chemical stability. Moreover, it showed efficient photocatalytic activity towards cross-dehydrogenative coupling (CDC) reactions between tetrahydroisoquinolines and nucleophiles such as nitromethane, acetone, and phenylethyl ketone. The metal-free catalytic system also offers attractive advantages including simplicity of operation, wide substrate adaptability, ambient reaction conditions, and robust recycling capability of the catalyst, thus providing a promising platform for highly efficient and reusable photocatalysts. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Reusable biocompatible interface for immobilization of materials on a solid support
Salamon, Zdzislaw; Schmidt, Richard A.; Tollin, Gordon; Macleod, H. Angus
1996-01-01
A method for the formation of a biocompatible film composed of a self-assembled bilayer membrane deposited on a planar surface. This bilayer membrane is capable of immobilizing materials to be analyzed in an environment very similar to their native state. Materials so immobilized may be subject to any of a number of analytical techniques.
Contracting/expanding self-sealing cryogenic tube seals
NASA Technical Reports Server (NTRS)
Jia, Lin X. (Inventor)
1997-01-01
Contracting/expanding self-sealing cryogenic tube seals are disclosed which use the different properties of thermal contraction and expansion of selected dissimilar materials in accord with certain design criteria to yield self-tightening seals via sloped-surface sealing. The seals of the subject invention are reusable, simple to assemble, and adaptable to a wide variety of cryogenic applications.
NASA Technical Reports Server (NTRS)
Ormiston, T.; Tanzilli, R. A.
1973-01-01
The development of reusable surface insulation materials that are thermal shock resistant and highly refractory is discussed. A stabilized, high-cristobalite, aluminum orthophosphate fiber was developed and found to possess the desired qualities. The application of such a material to heat shielding for space shuttles is examined.
Contracting/expanding self-sealing cryogenic tube seals
NASA Technical Reports Server (NTRS)
Jia, Lin X. (Inventor)
1997-01-01
Contracting/expanding self-sealing cryogenic tube seals are disclosed which use the different properties of thermal contraction and expansion of selected dissimilar materials in accord with certain design criteria to yield self-tightening seals via sloped-surface sealing. The seals of the subject invention are reusable, simple to assemble, adaptable to a wide variety of cryogenic applications.
Spacecraft thermal energy accommodation from atomic recombination
NASA Technical Reports Server (NTRS)
Carleton, Karen L.; Marinelli, William J.
1991-01-01
Measurements of atomic recombination probabilities important in determining energy release to reusable spacecraft thermal protection surfaces during reentry are presented. An experimental apparatus constructed to examine recombination of atomic oxygen from thermal protection and reference materials at reentry temperatures is described. The materials are examined under ultrahigh vacuum conditions to develop and maintain well characterized surface conditions that are free of contamination. When compared with stagnation point heat transfer measurements performed in arc jet facilities, these measurements indicate that a significant fraction of the excess energy available from atom recombination is removed from the surface as metastable O2.
Elongated solid electrolyte cell configurations and flexible connections therefor
Reichner, P.
1989-10-17
A flexible, high temperature, solid oxide electrolyte electrochemical cell stack configuration is made, comprising a plurality of flattened, elongated, connected cell combinations, each cell combination containing an interior electrode having a top surface and a plurality of interior gas feed conduits, through its axial length, electrolyte contacting the interior electrode and exterior electrode contacting electrolyte, where a major portion of the air electrode top surface is covered by interconnection material, and where each cell has at least one axially elongated, electronically conductive, flexible, porous, metal fiber felt material in electronic connection with the air electrode through contact with a major portion of the interconnection material, the metal fiber felt being effective as a shock absorbent body between the cells. 4 figs.
Lim, Chul-Hyun; Kim, Won Chul; Kim, Jin Soo; Cho, Yu Kyung; Park, Jae Myung; Lee, In Seok; Kim, Sang Woo; Choi, Kyu Yong; Chung, In-Sik
2012-01-01
Background/Aims It is believed that disposable biopsy forceps are more costly than reusable biopsy forceps. In this study, we evaluated performance and cost of disposable forceps versus reusable forceps in esophagogastroduodenoscopic biopsy. Methods Between October 2009 and July 2010, we enrolled 200 patients undergoing esophagogastroduodenoscopic biopsy at Seoul St. Mary's Hospital. Biopsies were performed with 100 disposable or 5 reusable forceps by random assignment. Seventy-five additional patients were studied to estimate durability of reusable forceps. The assisting nurses estimated the performance of the forceps. The evaluation of costs included purchase prices and reprocessing costs. The adequacy of the sample was estimated according to the diameter of the obtained tissue. Results Performance of disposable forceps was estimated as excellent in 97.0%, good in 2.0% and adequate in 1.0%. Reusable forceps were estimated as excellent in 36.0%, good in 36.0%, adequate in 25.1% and inadequate in 2.9%. The performance of reusable forceps declined with the number of uses. The reprocessing cost of reusable forceps for one biopsy session was calculated as ₩8,021. The adequacy of the sample was excellent for both forceps. Conclusions Disposable forceps showed excellent performance. Considering the reprocessing costs of reusable forceps, usage of disposable forceps with a low price should be considered. PMID:22741133
Knowledge-based reusable software synthesis system
NASA Technical Reports Server (NTRS)
Donaldson, Cammie
1989-01-01
The Eli system, a knowledge-based reusable software synthesis system, is being developed for NASA Langley under a Phase 2 SBIR contract. Named after Eli Whitney, the inventor of interchangeable parts, Eli assists engineers of large-scale software systems in reusing components while they are composing their software specifications or designs. Eli will identify reuse potential, search for components, select component variants, and synthesize components into the developer's specifications. The Eli project began as a Phase 1 SBIR to define a reusable software synthesis methodology that integrates reusabilityinto the top-down development process and to develop an approach for an expert system to promote and accomplish reuse. The objectives of the Eli Phase 2 work are to integrate advanced technologies to automate the development of reusable components within the context of large system developments, to integrate with user development methodologies without significant changes in method or learning of special languages, and to make reuse the easiest operation to perform. Eli will try to address a number of reuse problems including developing software with reusable components, managing reusable components, identifying reusable components, and transitioning reuse technology. Eli is both a library facility for classifying, storing, and retrieving reusable components and a design environment that emphasizes, encourages, and supports reuse.
Adler, S; Scherrer, M; Rückauer, K D; Daschner, F D
2005-02-01
The economic and environmental effects were compared between disposable and reusable instruments used for laparoscopic cholecystectomy. Special consideration was given to the processing of reusable instruments in the Miele G 7736 CD MCU washer disinfector and the resultant cost of sterilization. The instruments frequently used in their disposable form were identified with the help of surgeons. Thus, of all the instruments used for laparoscopic cholecystectomy, the disposable and reusable versions of trocars, scissors, and Veress cannula were compared. For the case examined in this study, the performance of laparoscopic cholecystectomy with disposable instruments was 19 times more expensive that for reusable instruments. The higher cost of using disposable instruments is primarily attributable to the purchase price of the instruments. The processing of reusable instruments has little significance in terms of cost, whereas the cost for disposing of disposable instruments is the least significant factor. The number of laparoscopic cholecystectomies performed per year does not substantially influence cost. In the authors' opinion, assessment of the environmental consequences shows that reusable instruments are environmentally advantageous. Considering the upward pressure of costs in hospitals, disposable instruments should be used for laparoscopic cholecystectomy only if they offer clear advantages over reusable instruments.
Disinfection of three wading boot surfaces infested with New Zealand mudsnails
Stockton, Kelly A.; Moffitt, Christine M.
2013-01-01
New Zealand mudsnails Potamopyrgus antipodarum (NZMS) have been introduced into many continents and are easily transported live while attached to wading and other field gear. We quantified the relative attachment by different life stages of NZMS to felt, neoprene, and rubber-soled boots exposed to two densities of NZMS in experimental exposure totes. Attachment by NZMS occurred on boots of all surfaces, but the highest numbers of all life stages occurred on boots with felt surfaces. We found a 15–20-min bath application of 20 g/L Virkon Aquatic was a reliable tool to disinfect boot surfaces infested with NZMS and other aquatic invertebrates. Our studies support that spray application of this disinfectant was not reliable to provide complete mortality of attached adult NZMS or neonates. Wading gear surfaces exposed to repeated bath disinfections showed little deterioration. Our results provide strong evidence that bath disinfections with Virkon Aquatic are helpful to assure biosecurity in field and hatchery settings, but applications should be coupled with cleaning procedures to remove organic materials that can deactivate the reagent.
Methodology for Assessing Reusability of Spaceflight Hardware
NASA Technical Reports Server (NTRS)
Childress-Thompson, Rhonda; Thomas, L. Dale; Farrington, Phillip
2017-01-01
In 2011 the Space Shuttle, the only Reusable Launch Vehicle (RLV) in the world, returned to earth for the final time. Upon retirement of the Space Shuttle, the United States (U.S.) no longer possessed a reusable vehicle or the capability to send American astronauts to space. With the National Aeronautics and Space Administration (NASA) out of the RLV business and now only pursuing Expendable Launch Vehicles (ELV), not only did companies within the U.S. start to actively pursue the development of either RLVs or reusable components, but entities around the world began to venture into the reusable market. For example, SpaceX and Blue Origin are developing reusable vehicles and engines. The Indian Space Research Organization is developing a reusable space plane and Airbus is exploring the possibility of reusing its first stage engines and avionics housed in the flyback propulsion unit referred to as the Advanced Expendable Launcher with Innovative engine Economy (Adeline). Even United Launch Alliance (ULA) has announced plans for eventually replacing the Atlas and Delta expendable rockets with a family of RLVs called Vulcan. Reuse can be categorized as either fully reusable, the situation in which the entire vehicle is recovered, or partially reusable such as the National Space Transportation System (NSTS) where only the Space Shuttle, Space Shuttle Main Engines (SSME), and Solid Rocket Boosters (SRB) are reused. With this influx of renewed interest in reusability for space applications, it is imperative that a systematic approach be developed for assessing the reusability of spaceflight hardware. The partially reusable NSTS offered many opportunities to glean lessons learned; however, when it came to efficient operability for reuse the Space Shuttle and its associated hardware fell short primarily because of its two to four-month turnaround time. Although there have been several attempts at designing RLVs in the past with the X-33, Venture Star and Delta Clipper Experimental (DC-X), reusability within the spaceflight arena is still in its infancy. With unlimited resources (namely, time and money), almost any launch vehicle and its associated hardware can be made reusable. However, an endless supply of funds for space exploration is not the case in today's economy for neither government agencies nor their commercial counterparts. Therefore, any organization wanting to be a leader in space exploration and remain competitive in this unforgiving space faring industry must confront shrinking budgets with more cost conscious and efficient designs. Therefore, standards for developing reusable spaceflight hardware need to be established. By having standards available to existing and emerging companies, some of the potential roadblocks and limitations that plagued previous attempts at reuse may be minimized or completely avoided.
NASA Astrophysics Data System (ADS)
Stickler, Patrick B.; Keller, Peter C.
1998-01-01
Reusable Launch Vehicles (RLV's) utilizing LOX\\LH2 as the propellant require lightweight durable structural systems to meet mass fraction goals and to reduce overall systems operating costs. Titanium honeycomb sandwich with flexible blanket TPS on the windward surface is potentially the lightest-weight and most operable option. Light weight is achieved in part because the honeycomb sandwich tank provides insulation to its liquid hydrogen contents, with no need for separate cryogenic insulation, and in part because the high use temperature of titanium honeycomb reduces the required surface area of re-entry thermal protection systems. System operability is increased because TPS needs to be applied only to surfaces where temperatures exceed approximately 650 K. In order to demonstrate the viability of a titanium sandwich constructed propellant tank, a technology demonstration program was conducted including the design, fabrication and testing of a propellant tank-TPS system. The tank was tested in controlled as well as ambient environments representing ground hold conditions for a RLV main propellant tank. Data collected during each test run was used to validate predictions for air liquefaction, outside wall temperature, boil-off rates, frost buildup and its insulation effects, and the effects of placing a thermal protection system blanket on the external surface. Test results indicated that titanium honeycomb, when used as a RLV propellant tank material, has great promise as a light-weight structural system.
Reusable rocket engine optical condition monitoring
NASA Technical Reports Server (NTRS)
Wyett, L.; Maram, J.; Barkhoudarian, S.; Reinert, J.
1987-01-01
Plume emission spectrometry and optical leak detection are described as two new applications of optical techniques to reusable rocket engine condition monitoring. Plume spectrometry has been used with laboratory flames and reusable rocket engines to characterize both the nominal combustion spectra and anomalous spectra of contaminants burning in these plumes. Holographic interferometry has been used to identify leaks and quantify leak rates from reusable rocket engine joints and welds.
Toward Reusable Graphics Components in Ada
1993-03-01
Then alternatives for obtaining well- engineered reusable software components were examined. Finally, the alternatives were analyzed, and the most...reusable software components. Chapter 4 describes detailed design and implementation strategies in building a well- engineered reusable set of components in...study. 2.2 The Object-Oriented Paradigm 2.2.1 The Need for Object-Oriented Techniques. Among software engineers the software crisis is a well known
Space Transportation Infrastructure Supported By Propellant Depots
NASA Technical Reports Server (NTRS)
Smitherman, David; Woodcock, Gordon
2012-01-01
A space transportation infrastructure is described that utilizes propellant depot servicing platforms to support all foreseeable missions in the Earth-Moon vicinity and deep space out to Mars. The infrastructure utilizes current expendable launch vehicle (ELV) systems such as the Delta IV Heavy, Atlas V, and Falcon 9, for all crew, cargo, and propellant launches to orbit. Propellant launches are made to Low-Earth-Orbit (LEO) Depot and an Earth-Moon Lagrange Point 1 (L1) Depot to support a new reusable in-space transportation vehicles. The LEO Depot supports missions to Geosynchronous Earth Orbit (GEO) for satellite servicing and to L1 for L1 Depot missions. The L1 Depot supports Lunar, Earth-Sun L2 (ESL2), Asteroid and Mars Missions. New vehicle design concepts are presented that can be launched on current 5 meter diameter ELV systems. These new reusable vehicle concepts include a Crew Transfer Vehicle (CTV) for crew transportation between the LEO Depot, L1 Depot and missions beyond L1; a new reusable lunar lander for crew transportation between the L1 Depot and the lunar surface; and Mars orbital Depot are based on International Space Station (ISS) heritage hardware. Data provided includes the number of launches required for each mission utilizing current ELV systems (Delta IV Heavy or equivalent) and the approximate vehicle masses and propellant requirements. Also included is a discussion on affordability with ideas on technologies that could reduce the number of launches required and thoughts on how this infrastructure include competitive bidding for ELV flights and propellant services, developments of new reusable in-space vehicles and development of a multiuse infrastructure that can support many government and commercial missions simultaneously.
Cost analysis of single-use (Ambu® aScope™) and reusable bronchoscopes in the ICU.
Perbet, S; Blanquet, M; Mourgues, C; Delmas, J; Bertran, S; Longère, B; Boïko-Alaux, V; Chennell, P; Bazin, J-E; Constantin, J-M
2017-12-01
Flexible optical bronchoscopes are essential for management of airways in ICU, but the conventional reusable flexible scopes have three major drawbacks: high cost of repairs, need for decontamination, and possible transmission of infectious agents. The main objective of this study was to measure the cost of bronchoalveolar lavage (BAL) and percutaneous tracheostomy (PT) using reusable bronchoscopes and single-use bronchoscopes in an ICU of an university hospital. The secondary objective was to compare the satisfaction of healthcare professionals with reusable and single-use bronchoscopes. The study was performed between August 2009 and July 2014 in a 16-bed ICU. All BAL and PT procedures were performed by experienced healthcare professionals. Cost analysis was performed considering ICU and hospital organization. Healthcare professional satisfaction with single-use and reusable scopes was determined based on eight factors. Sensitivity analysis was performed by applying discount rates (0, 3, and 5%) and by simulation of six situations based on different assumptions. At a discount rate of 3%, the costs per BAL for the two reusable scopes were 188.86€ (scope 1) and 185.94€ (scope 2), and the costs per PT for the reusable scope 1 and scope 2 and single-use scopes were 1613.84€, 410.24€, and 204.49€, respectively. The cost per procedure for the reusable scopes depended on the number of procedures performed, maintenance costs, and decontamination costs. Healthcare professionals were more satisfied with the third-generation single-use Ambu ® aScope™. The cost per procedure for the single-use scope was not superior to that for reusable scopes. The choice of single-use or reusable bronchoscopes in an ICU should consider the frequency of procedures and the number of bronchoscopes needed.
2003-10-01
KENNEDY SPACE CENTER, FLA. - In the Orbiter Processing Facility, Ryan Levann, with United Space Alliance, checks data on the tile removed from the thermal barrier around the umbilical areas, the external tank attach points, on the underside of Atlantis. The umbilical areas are closed off after ET separation by a door, seen here. The exposed area of each closed door is covered with reusable surface insulation.
Reusable biocompatible interface for immobilization of materials on a solid support
Salamon, Z.; Schmidt, R.A.; Tollin, G.; Macleod, H.A.
1996-05-28
A method is presented for the formation of a biocompatible film composed of a self-assembled bilayer membrane deposited on a planar surface. This bilayer membrane is capable of immobilizing materials to be analyzed in an environment very similar to their native state. Materials so immobilized may be subject to any of a number of analytical techniques. 3 figs.
Supercavitating Projectile Tracking System and Method
2009-12-30
Distribution is unlimited 20100104106 Attorney Docket No. 96681 SUPERCAVITATING PROJECTILE TRACKING SYSTEM AND METHOD STATEMENT OF GOVERNMENT...underwater track or path 14 of a supercavitating vehicle under surface 16 of a body of water. In this embodiment, passive acoustic or pressure...transducers 12 are utilized to measure a pressure field produced by a moving supercavitating vehicle. The present invention provides a low-cost, reusable
NASA Technical Reports Server (NTRS)
Shtessel, Yuri B.
2002-01-01
In this report we present a time-varying sliding mode control (TV-SMC) technique for reusable launch vehicle (RLV) attitude control in ascent and entry flight phases. In ascent flight the guidance commands Euler roll, pitch and yaw angles, and in entry flight it commands the aerodynamic angles of bank, attack and sideslip. The controller employs a body rate inner loop and the attitude outer loop, which are separated in time-scale by the singular perturbation principle. The novelty of the TVSMC is that both the sliding surface and the boundary layer dynamics can be varied in real time using the PD-eigenvalue assignment technique. This salient feature is used to cope with control command saturation and integrator windup in the presence of severe disturbance or control effector failure, which enhances the robustness and fault tolerance of the controller. The TV-SMC is developed and tuned up for the X-33 sub-orbital technology demonstration vehicle in launch and re-entry modes. A variety of nominal, dispersion and failure scenarios have tested via high fidelity 6DOF simulations using MAVERIC/SLIM simulation software.
NASA Technical Reports Server (NTRS)
Ojalvo, I. U.; Austin, F.; Levy, A.
1974-01-01
An efficient iterative procedure is described for the vibration and modal stress analysis of reusable surface insulation (RSI) of multi-tiled space shuttle panels. The method, which is quite general, is rapidly convergent and highly useful for this application. A user-oriented computer program based upon this procedure and titled RESIST (REusable Surface Insulation Stresses) has been prepared for the analysis of compact, widely spaced, stringer-stiffened panels. RESIST, which uses finite element methods, obtains three dimensional tile stresses in the isolator, arrestor (if any) and RSI materials. Two dimensional stresses are obtained in the tile coating and the stringer-stiffened primary structure plate. A special feature of the program is that all the usual detailed finite element grid data is generated internally from a minimum of input data. The program can accommodate tile idealizations with up to 850 nodes (2550 degrees-of-freedom) and primary structure idealizations with a maximum of 10,000 degrees-of-freedom. The primary structure vibration capability is achieved through the development of a new rapid eigenvalue program named ALARM (Automatic LArge Reduction of Matrices to tridiagonal form).
Improvement of Reusable Surface Insulation (RSI) materials
NASA Technical Reports Server (NTRS)
Blome, J. C.
1972-01-01
The mullite fiber based hardened compacted fibers (HCF) type of reusable surface insulation was further developed for use in the Space Shuttle Program. Two hundred fifty formulations of fiber mixtures, fillers, binders, and organic processing aids were made using mullite fibers as the basic ingredient. Most of the work was accomplished on 15-lb/cu ft material. It was established that higher density materials are stronger with strength values as high as 250 lb/sq in. in tension. New measurement techniques and equipment were developed for accurate determination of strength and strain to failure. Room temperature to 2300 F stress-strain relationships were made. The room temperature tensile modulus of elasticity is 61,700 lb/sq in. and the strain at failure is 0.165 percent, typically, when measured longitudinally parallel to the long axes of the fibers. Thermal insulating effectiveness was increased 20 percent by reducing the diameter of some of the fibers in the material. Improvements were made in density uniformity and strength uniformity in a block of HCF by mixing improvements and by the use of organic additives. Specifications were established on the materials and processes used in making the insulation.
NASA Astrophysics Data System (ADS)
Mahulikar, Shripad P.; Khurana, Shashank; Dungarwal, Ritesh; Shevakari, Sushil G.; Subramanian, Jayakumar; Gujarathi, Amit V.
2008-12-01
The temperature field history of passive Thermal Protection System (TPS) material at the nose-cap (forward stagnation region) of a Reusable Hypersonic Vehicle (RHV) is generated. The 3-D unsteady heat transfer model couples conduction in the solid with external convection and radiation that are modeled as time-varying boundary conditions on the surface. Results are presented for the following two cases: (1) nose-cap comprised of ablative TPS material only (SIRCA/PICA), and (2) nose-cap comprised of a combination of ablative TPS material with moderate thermal conductivity and insulative TPS material. Comparison of the temperature fields of SIRCA and PICA [Case (1)] indicates lowering of the peak stagnation region temperatures for PICA, due to its higher thermal conductivity. Also, the use of PICA and insulative TPS [Case (2)] for the nose-cap has higher potential for weight reduction than the use of ablative TPS alone.
Hu, Zunfang; Xu, Longqian; Wen, Xianghua
2013-01-01
Immobilization of enzymes on mesoporous silicas (MS) allows for good reusability. MS with two-dimensional hexagonal pores in diameter up to 14.13 nm were synthesized using Pluronic P123 as template and 1,3,5-triisopropylbenzene as a swelling agent in acetate buffer. The surface of MS was modified by the silanization reagents 3-aminopropyltriethoxysilane. Lignin peroxidase (LiP) was successfully immobilized on the modified MS through covalent binding method by four agents: glutaraldehyde, 1,4-phenylene diisothiocyanate, cyanotic chloride and water-soluble carbodiimide. Results showed that cyanotic chloride provided the best performance for LIP immobilization. The loaded protein concentration was 12.15 mg/g and the immobilized LiP activity was 812.9 U/L. Immobilized LiP had better pH stability. Acid Orange II was used to examine the reusability of immobilized LiP, showing more than 50% of the dye was decolorized at the fifth cycle.
Lunar lander conceptual design
NASA Technical Reports Server (NTRS)
Stecklein, J. M.; Petro, A. J.; Stump, W. R.; Adorjan, A. S.; Chambers, T. V.; Donofrio, M.; Hirasaki, J. K.; Morris, O. G.; Nudd, G.; Rawlings, R. P.
1992-01-01
This paper is a first look at the problems of building a lunar lander to support a small lunar surface base. A series of trade studies was performed to define the lander. The initial trades concerned choosing number of stages, payload mass, parking orbit altitude, and propellant type. Other important trades and issues included plane change capability, propellant loading and maintenance location, and reusability considerations. Given a rough baseline, the systems were then reviewed. A conceptual design was then produced. The process was carried through only one iteration. Many more iterations are needed. A transportation system using reusable, aerobraked orbital transfer vehicles (OTV's) is assumed. These OTV's are assumed to be based and maintained at a low Earth orbit (LEO) space station, optimized for transportation functions. Single- and two-stage OTV stacks are considered. The OTV's make the translunar injection (TLI), lunar orbit insertion (LOI), and trans-Earth injection (TEI) burns, as well as midcourse and perigee raise maneuvers.
Chang, Yuanyuan; Zhuo, Ying; Chai, Yaqin; Yuan, Ruo
2017-08-15
In this work, an elegantly designed host-guest recognition-assisted electrochemical release was established and applied in a reusable electrochemical biosensor for the detection of microRNA-182-5p (miRNA-182-5p), a prostate cancer biomarker in prostate cancer, based on the DNA cross configuration-fueled target cycling and strand displacement reaction (SDR) amplification. With such a design, the single target miRNA input could be converted to large numbers of single-stranded DNA (S1-Trp and S2-Trp) output, which could be trapped by cucurbit[8]uril methyl viologen (CB-8-MV 2+ ) based on the host-guest recognition, significantly enhancing the sensitivity for miRNA detection. Moreover, the nucleic acids products obtained from the process of cycling amplification could be utilized sufficiently, avoiding the waste and saving the experiment cost. Impressively, by resetting a settled voltage, the proposed biosensor could release S1-Trp and S2-Trp from the electrode surface, attributing that the guest ion methyl viologen (MV 2+ ) was reduced to MV +· under this settled voltage and formed a more-stable CB-8-MV +· -MV +· complex. Once O 2 was introduced in this system, MV +· could be oxidized to MV 2+ , generating the complex of CB-8-MV 2+ for capturing S1-Trp and S2-Trp again in only 5 min. As a result, the simple and fast regeneration of biosensor for target detection was realized on the base of electrochemical redox-driven assembly and release, overcoming the challenges of time-consuming, burdensome operations and expensive experimental cost in traditional reusable biosensors and updating the construction method for a reusable bisensor. Furthermore, the biosensor could be reused for more than 10 times with a regeneration rate of 93.20%-102.24%. After all, the conception of this work provides a novel thought for the construction of effective reusable biosensor to detect miRNA and other biomarkers and has great potential application in the area requiring the release of nucleic acids or proteins.
Electric and Hydraulic Properties of Carbon Felt Immersed in Different Dielectric Liquids
Kossenko, Alexey; Lugovskoy, Svetlana
2018-01-01
Electroconductive carbon felt (CF) material, having a permeable structure and significant electroconductive surface, is widely used for electrodes in numerous electrochemical applications such as redox flow batteries, fuel cells, electrochemical desalination apparatus, etc. The internal structure of CF is composed of different lengths of carbon filaments bonded together. This structure creates a large number of stochastically oriented and stochastically linked channels that have different lengths and cross sections. Therefore, the CF hydraulic permeability is similar to that of porous media and is determined by the internal empty volume and arrangement of carbon fibers. Its electroconductivity is ensured by the conductivity of the carbon filaments and by the electrical interconnections between fibers. Both of these properties (permeability and electrical conductivity) are extremely important for the efficient functioning of electrochemical devices. However, their influences counter each other during CF compressing. Increasing the stress on a felt element provides supplementary electrical contacts of carbon filaments, which lead to improved electrical conductivity. Thus, the active surface of the felt electrode is increased, which also boosts redox chemical reactions. On the other hand, compressed felt possesses reduced hydrodynamic permeability as a result of a diminished free volume of porous media and intrinsic channels. This causes increasing hydrodynamic expenditures of electrolyte pumping through electrodes and lessened cell (battery) efficiency. The designer of specific electrochemical systems has to take into account both of these properties when selecting the optimal construction for a cell. This article presents the results of measurements and novel approximating expressions of electrical and hydraulic characteristics of a CF during its compression. Since electrical conductivity plays a determining role in providing electrochemical reactions, it was measured in dry conditions and when the CF was immersed in several non-conductive liquids. The choice of such liquids prevented side effects of electrolyte ionic conductivity impact on electrical resistivity of the CF. This gave an opportunity to determine the influences of dielectric parameters of electrolytes to increase or decrease the density of interconnectivity of carbon fibers either between themselves or between them and electrodes. The experiments showed the influence of liquid permittivity on the conductivity of CF, probably by changing the density of fiber interconnections inside the felt. PMID:29690636
Electric and Hydraulic Properties of Carbon Felt Immersed in Different Dielectric Liquids.
Kossenko, Alexey; Lugovskoy, Svetlana; Averbukh, Moshe
2018-04-23
Electroconductive carbon felt (CF) material, having a permeable structure and significant electroconductive surface, is widely used for electrodes in numerous electrochemical applications such as redox flow batteries, fuel cells, electrochemical desalination apparatus, etc. The internal structure of CF is composed of different lengths of carbon filaments bonded together. This structure creates a large number of stochastically oriented and stochastically linked channels that have different lengths and cross sections. Therefore, the CF hydraulic permeability is similar to that of porous media and is determined by the internal empty volume and arrangement of carbon fibers. Its electroconductivity is ensured by the conductivity of the carbon filaments and by the electrical interconnections between fibers. Both of these properties (permeability and electrical conductivity) are extremely important for the efficient functioning of electrochemical devices. However, their influences counter each other during CF compressing. Increasing the stress on a felt element provides supplementary electrical contacts of carbon filaments, which lead to improved electrical conductivity. Thus, the active surface of the felt electrode is increased, which also boosts redox chemical reactions. On the other hand, compressed felt possesses reduced hydrodynamic permeability as a result of a diminished free volume of porous media and intrinsic channels. This causes increasing hydrodynamic expenditures of electrolyte pumping through electrodes and lessened cell (battery) efficiency. The designer of specific electrochemical systems has to take into account both of these properties when selecting the optimal construction for a cell. This article presents the results of measurements and novel approximating expressions of electrical and hydraulic characteristics of a CF during its compression. Since electrical conductivity plays a determining role in providing electrochemical reactions, it was measured in dry conditions and when the CF was immersed in several non-conductive liquids. The choice of such liquids prevented side effects of electrolyte ionic conductivity impact on electrical resistivity of the CF. This gave an opportunity to determine the influences of dielectric parameters of electrolytes to increase or decrease the density of interconnectivity of carbon fibers either between themselves or between them and electrodes. The experiments showed the influence of liquid permittivity on the conductivity of CF, probably by changing the density of fiber interconnections inside the felt.
Replication of patterned thin-film structures for use in plasmonics and metamaterials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Norris, David J; Han, Sang Eon; Bhan, Aditya
The present invention provides templating methods for replicating patterned metal films from a template substrate such as for use in plasmonic devices and metamaterials. Advantageously, the template substrate is reusable and can provide plural copies of the structure of the template substrate. Because high-quality substrates that are inherently smooth and flat are available, patterned metal films in accordance with the present invention can advantageously provide surfaces that replicate the surface characteristics of the template substrate both in the patterned regions and in the unpatterned regions.
Advanced High Temperature Structural Seals
NASA Astrophysics Data System (ADS)
Newquist, Charles W.; Verzemnieks, Juris; Keller, Peter C.; Rorabaugh, Michael; Shorey, Mark
2002-10-01
This program addresses the development of high temperature structural seals for control surfaces for a new generation of small reusable launch vehicles. Successful development will contribute significantly to the mission goal of reducing launch cost for small, 200 to 300 pound payloads. Development of high temperature seals is mission enabling. For instance, ineffective control surface seals can result in high temperature (3100 F) flows in the elevon area exceeding structural material limits. Longer sealing life will allow use for many missions before replacement, contributing to the reduction of hardware, operation and launch costs.
Advanced High Temperature Structural Seals
NASA Technical Reports Server (NTRS)
Newquist, Charles W.; Verzemnieks, Juris; Keller, Peter C.; Rorabaugh, Michael; Shorey, Mark
2002-01-01
This program addresses the development of high temperature structural seals for control surfaces for a new generation of small reusable launch vehicles. Successful development will contribute significantly to the mission goal of reducing launch cost for small, 200 to 300 pound payloads. Development of high temperature seals is mission enabling. For instance, ineffective control surface seals can result in high temperature (3100 F) flows in the elevon area exceeding structural material limits. Longer sealing life will allow use for many missions before replacement, contributing to the reduction of hardware, operation and launch costs.
Closeup view of the aft fuselage looking forward along the ...
Close-up view of the aft fuselage looking forward along the approximate centerline of the Orbiter Discovery looking at the expansion nozzles of the Space Shuttle Main Engines (SSME) and the Orbiter Maneuvering System. Also in the view is the orbiter's body flap with a protective covering over the High-temperature Reusable Surface Insulation tiles on the surface facing the SSMEs. This image was taken inside the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Elongated solid electrolyte cell configurations and flexible connections therefor
Reichner, Philip
1989-01-01
A flexible, high temperature, solid oxide electrolyte electrochemical cell stack configuration is made, comprising a plurality of flattened, elongated, connected cell combinations 1, each cell combination containing an interior electrode 2 having a top surface and a plurality of interior gas feed conduits 3, through its axial length, electrolyte 5 contacting the interior electrode and exterior electrode 8 contacting electrolyte, where a major portion of the air electrode top surface 7 is covered by interconnection material 6, and where each cell has at least one axially elongated, electronically conductive, flexible, porous, metal fiber felt material 9 in electronic connection with the air electrode 2 through contact with a major portion of the interconnection material 6, the metal fiber felt being effective as a shock absorbent body between the cells.
NASA Technical Reports Server (NTRS)
DelPapa, Steven V.
2005-01-01
Arc jet tests of candidate tile repair materials and baseline Orbiter uncoated reusable surface insulation (RSI) were performed in the Johnson Space Center's (JSC) Atmospheric Reentry Materials and Structures Evaluation Facility (ARMSEF) from June 23, 2003, through August 19, 2003. These tests were performed to screen candidate tile repair materials by verifying the high temperature performance and determining the thermal stability. In addition, tests to determine the surface emissivity at high temperatures and the geometric shrinkage of bare RSI were performed. In addition, tests were performed to determine the surface emissivity at high temperatures and the geometric shrinkage of uncoated RSI.
Estevez, Luis; Reed, David; Nie, Zimin; Schwarz, Ashleigh M; Nandasiri, Manjula I; Kizewski, James P; Wang, Wei; Thomsen, Edwin; Liu, Jun; Zhang, Ji-Guang; Sprenkle, Vincent; Li, Bin
2016-06-22
A dual oxidative approach using O2 plasma followed by treatment with H2 O2 to impart oxygen functional groups onto the surface of a graphite felt electrode. When used as electrodes for an all-vanadium redox flow battery (VRB) system, the energy efficiency of the cell is enhanced by 8.2 % at a current density of 150 mA cm(-2) compared with one oxidized by thermal treatment in air. More importantly, by varying the oxidative techniques, the amount and type of oxygen groups was tailored and their effects were elucidated. It was found that O-C=O groups improve the cells performance whereas the C-O and C=O groups degrade it. The reason for the increased performance was found to be a reduction in the cell overpotential after functionalization of the graphite felt electrode. This work reveals a route for functionalizing carbon electrodes to improve the performance of VRB cells. This approach can lower the cost of VRB cells and pave the way for more commercially viable stationary energy storage systems that can be used for intermittent renewable energy storage. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Schwenke, A. M.; Janoschka, T.; Stolze, C.; Martin, N.; Hoeppener, S.; Schubert, U. S.
2016-12-01
A simple and fast microwave-assisted protocol to functionalize commercially available graphite felts (GFs) with carbon nanofibers (CNFs) for the application as electrode materials in redox-flow batteries (RFB) is demonstrated. As catalyst for the CNF synthesis nickel acetate is applied and ethanol serves as the carbon source. By the in-situ growth of CNFs, the active surface of the electrodes is increased by a factor of 50, which is determined by the electrochemical double layer capacities of the obtained materials. Furthermore, the morphology of the CNF-coating is investigated by scanning electron microscopy. Subsequently, the functionalized electrodes are applied in a polymer-based redox-flow battery (pRFB) using a TEMPO- and a viologen polymer as active materials. Due to the increased surface area as compared to an untreated graphite felt electrode, the current rating is improved by about 45% at 80 mA cm-2 and, furthermore, a decrease in overpotentials is observed. Thus, using this microwave-assisted synthesis approach, CNF-functionalized composite electrodes are prepared with a very simple protocol suitable for real life applications and an improvement of the overall performance of the polymer-based redox-flow battery is demonstrated.
Mechanically expandable annular seal
Gilmore, R.F.
1983-07-19
A mechanically expandable annular reusable seal assembly to form an annular hermetic barrier between two stationary, parallel, and planar containment surfaces is described. A rotatable ring, attached to the first surface, has ring wedges resembling the saw-tooth array of a hole saw. Matching seal wedges are slidably attached to the ring wedges and have their motion restricted to be perpendicular to the second surface. Each seal wedge has a face parallel to the second surface. An annular elastomer seal has a central annular region attached to the seal wedges' parallel faces and has its inner and outer circumferences attached to the first surface. A rotation of the ring extends the elastomer seal's central region perpendicularly towards the second surface to create the fluid tight barrier. A counter rotation removes the barrier. 6 figs.
Cartwright, J A; Hill, T L; Smith, S; Shaw, D
2016-07-01
Sample quality of gastrointestinal endoscopic biopsies is of paramount importance for accurate histological diagnosis. Many veterinary practices use reusable forceps as a result of perceived decreased cost. With reusable forceps, it remains unknown whether sample quality declines with repeated use and becomes inferior to single-use forceps and is therefore more or less cost effective than single-use forceps. The study hypothesis was that reusable forceps sample quality would deteriorate after repeated use as compared to single-use forceps. Sixty-five dogs undergoing gastrointestinal endoscopy for diagnostic investigations at the Hospital for Small Animals, Edinburgh University. A prospective, pathologist-blinded study comparing single-use and reusable alligator standard cup biopsy forceps (Olympus 2.0 mm 1550 mm) with 5 randomized reusable forceps. Sample quality (stomach, duodenum, ileum, and colon) was assessed by a single pathologist using the WSAVA guidelines. There was no difference in the adequacy, depth, villi number, or crush artifact in the 4 intestinal areas between forceps type with at least 10, and up to 15, repeated uses of the reusable forceps. This study demonstrates that reusable cup biopsy forceps provide equivalent biopsy quality after repeated uses to single-use forceps and are cost effective at 10-case use. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Detail view of the underside of a elevon on the ...
Detail view of the underside of a elevon on the port side wing of the Orbiter Discovery. Note the wear and replacement patterns of the High-temperature Reusable Surface Insulation tiles. This image was taken inside of the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Improved coating for silica fiber based ceramic Reusable Surface Insulation (CRSI)
NASA Technical Reports Server (NTRS)
Ormiston, T. J.
1974-01-01
A series of coatings was developed for the space shuttle type silica fiber insulation system and characterized for optical and physical properties. Reentry simulation tests were run using a radiant panel and also using a hypersonic plasma arc. The coatings produced had improved physical and optical properties as well as greater reuse capability over the GE version of the JSC-0042 coating.
Thermal stress analysis of reusable surface insulation for shuttle
NASA Technical Reports Server (NTRS)
Ojalvo, I. U.; Levy, A.; Austin, F.
1974-01-01
An iterative procedure for accurately determining tile stresses associated with static mechanical and thermally induced internal loads is presented. The necessary conditions for convergence of the method are derived. An user-oriented computer program based upon the present method of analysis was developed. The program is capable of analyzing multi-tiled panels and determining the associated stresses. Typical numerical results from this computer program are presented.
Structural Integrity and Durability of Reusable Space Propulsion Systems
NASA Technical Reports Server (NTRS)
1985-01-01
The space shuttle main engine (SSME), a reusable space propulsion system, is discussed. The advances in high pressure oxygen hydrogen rocket technology are reported to establish the basic technology and to develop new analytical tools for the evaluation in reusable rocket systems.
Air Force Reusable Booster System A Quick-look, Design Focused Modeling and Cost Analysis Study
NASA Technical Reports Server (NTRS)
Zapata, Edgar
2011-01-01
Presents work supporting the Air force Reusable Booster System (RBS) - A Cost Study with Goals as follows: Support US launch systems decision makers, esp. in regards to the research, technology and demonstration investments required for reusable systems to succeed. Encourage operable directions in Reusable Booster / Launch Vehicle Systems technology choices, system design and product and process developments. Perform a quick-look cost study, while developing a cost model for more refined future analysis.
Reusable high-temperature heat pipes and heat pipe panels
NASA Technical Reports Server (NTRS)
Camarda, Charles J. (Inventor); Ransone, Philip O. (Inventor)
1989-01-01
A reusable, durable heat pipe which is capable of operating at temperatures up to about 3000 F in an oxidizing environment and at temperatures above 3000 F in an inert or vacuum environment is produced by embedding a refractory metal pipe within a carbon-carbon composite structure. A reusable, durable heat pipe panel is made from an array of refractory-metal pipes spaced from each other. The reusable, durable, heat-pipe is employed to fabricate a hypersonic vehicle leading edge and nose cap.
A Framework for Assessing the Reusability of Hardware (Reusable Rocket Engines)
NASA Technical Reports Server (NTRS)
Childress-Thompson, Rhonda; Farrington, Philip; Thomas, Dale
2016-01-01
Within the space flight community, reusability has taken center stage as the new buzzword. In order for reusable hardware to be competitive with its expendable counterpart, two major elements must be closely scrutinized. First, recovery and refurbishment costs must be lower than the development and acquisition costs. Additionally, the reliability for reused hardware must remain the same (or nearly the same) as "first use" hardware. Therefore, it is imperative that a systematic approach be established to enhance the development of reusable systems. However, before the decision can be made on whether it is more beneficial to reuse hardware or to replace it, the parameters that are needed to deem hardware worthy of reuse must be identified. For reusable hardware to be successful, the factors that must be considered are reliability (integrity, life, number of uses), operability (maintenance, accessibility), and cost (procurement, retrieval, refurbishment). These three factors are essential to the successful implementation of reusability while enabling the ability to meet performance goals. Past and present strategies and attempts at reuse within the space industry will be examined to identify important attributes of reusability that can be used to evaluate hardware when contemplating reusable versus expendable options. This paper will examine why reuse must be stated as an initial requirement rather than included as an afterthought in the final design. Late in the process, changes in the overall objective/purpose of components typically have adverse effects that potentially negate the benefits. A methodology for assessing the viability of reusing hardware will be presented by using the Space Shuttle Main Engine (SSME) to validate the approach. Because reliability, operability, and costs are key drivers in making this critical decision, they will be used to assess requirements for reuse as applied to components of the SSME.
Liu, Yang; Zhou, Junbo
2014-01-01
The chemical vapor deposition method is used to prepare CNT (carbon nanotube)/PCF (PAN-based carbon fiber felt) composite electrodes in this paper, with the surface morphology of CNT/PCF composites and electroadsorption desalination performance being studied. Results show such electrode materials with three-dimensional network nanostructures having a larger specific surface area and narrower micropore distribution, with a huge number of reactive groups covering the surface. Compared with PCF electrodes, CNT/PCF can allow for a higher adsorption and desorption rate but lower energy consumption; meanwhile, under the condition of the same voltage change, the CNT/PCF electrodes are provided with a better desalination effect. The study also found that the higher the original concentration of the solution, the greater the adsorption capacity and the lower the adsorption rate. At the same time, the higher the solution's pH, the better the desalting; the smaller the ions' radius, the greater the amount of adsorption. PMID:24963504
14 CFR 437.95 - Inspection of additional reusable suborbital rockets.
Code of Federal Regulations, 2010 CFR
2010-01-01
... AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.95 Inspection of additional reusable suborbital rockets. A permittee may launch or reenter additional reusable suborbital rockets of the same design under the permit after...
14 CFR 437.95 - Inspection of additional reusable suborbital rockets.
Code of Federal Regulations, 2012 CFR
2012-01-01
... AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.95 Inspection of additional reusable suborbital rockets. A permittee may launch or reenter additional reusable suborbital rockets of the same design under the permit after...
14 CFR 437.95 - Inspection of additional reusable suborbital rockets.
Code of Federal Regulations, 2014 CFR
2014-01-01
... AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.95 Inspection of additional reusable suborbital rockets. A permittee may launch or reenter additional reusable suborbital rockets of the same design under the permit after...
14 CFR 437.95 - Inspection of additional reusable suborbital rockets.
Code of Federal Regulations, 2013 CFR
2013-01-01
... AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.95 Inspection of additional reusable suborbital rockets. A permittee may launch or reenter additional reusable suborbital rockets of the same design under the permit after...
14 CFR 437.95 - Inspection of additional reusable suborbital rockets.
Code of Federal Regulations, 2011 CFR
2011-01-01
... AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.95 Inspection of additional reusable suborbital rockets. A permittee may launch or reenter additional reusable suborbital rockets of the same design under the permit after...
Sherman, Jodi D; Raibley, Lewis A; Eckelman, Matthew J
2018-01-09
Traditional medical device procurement criteria include efficacy and safety, ease of use and handling, and procurement costs. However, little information is available about life cycle environmental impacts of the production, use, and disposal of medical devices, or about costs incurred after purchase. Reusable and disposable laryngoscopes are of current interest to anesthesiologists. Facing mounting pressure to quickly meet or exceed conflicting infection prevention guidelines and oversight body recommendations, many institutions may be electively switching to single-use disposable (SUD) rigid laryngoscopes or overcleaning reusables, potentially increasing both costs and waste generation. This study provides quantitative comparisons of environmental impacts and total cost of ownership among laryngoscope options, which can aid procurement decision making to benefit facilities and public health. We describe cradle-to-grave life cycle assessment (LCA) and life cycle costing (LCC) methods and apply these to reusable and SUD metal and plastic laryngoscope handles and tongue blade alternatives at Yale-New Haven Hospital (YNHH). The US Environmental Protection Agency's Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) life cycle impact assessment method was used to model environmental impacts of greenhouse gases and other pollutant emissions. The SUD plastic handle generates an estimated 16-18 times more life cycle carbon dioxide equivalents (CO2-eq) than traditional low-level disinfection of the reusable steel handle. The SUD plastic tongue blade generates an estimated 5-6 times more CO2-eq than the reusable steel blade treated with high-level disinfection. SUD metal components generated much higher emissions than all alternatives. Both the SUD handle and SUD blade increased life cycle costs compared to the various reusable cleaning scenarios at YNHH. When extrapolated over 1 year (60,000 intubations), estimated costs increased between $495,000 and $604,000 for SUD handles and between $180,000 and $265,000 for SUD blades, compared to reusables, depending on cleaning scenario and assuming 4000 (rated) uses. Considering device attrition, reusable handles would be more economical than SUDs if they last through 4-5 uses, and reusable blades 5-7 uses, before loss. LCA and LCC are feasible methods to ease interpretation of environmental impacts and facility costs when weighing device procurement options. While management practices vary between institutions, all standard methods of cleaning were evaluated and sensitivity analyses performed so that results are widely applicable. For YNHH, the reusable options presented a considerable cost advantage, in addition to offering a better option environmentally. Avoiding overcleaning reusable laryngoscope handles and blades is desirable from an environmental perspective. Costs may vary between facilities, and LCC methodology demonstrates the importance of time-motion labor analysis when comparing reusable and disposable device options.
Reusable Launch Vehicle Technology Program
NASA Technical Reports Server (NTRS)
Freeman, Delma C., Jr.; Talay, Theodore A.; Austin, R. Eugene
1996-01-01
Industry/NASA Reusable Launch Vehicle (RLV) Technology Program efforts are underway to design, test, and develop technologies and concepts for viable commercial launch systems that also satisfy national needs at acceptable recurring costs. Significant progress has been made in understanding the technical challenges of fully reusable launch systems and the accompanying management and operational approaches for achieving a low-cost program. This paper reviews the current status of the Reusable Launch Vehicle Technology Program including the DC-XA, X-33 and X-34 flight systems and associated technology programs. It addresses the specific technologies being tested that address the technical and operability challenges of reusable launch systems including reusable cryogenic propellant tanks, composite structures, thermal protection systems, improved propulsion, and subsystem operability enhancements. The recently concluded DC-XA test program demonstrated some of these technologies in ground and flight tests. Contracts were awarded recently for both the X-33 and X-34 flight demonstrator systems. The Orbital Sciences Corporation X-34 flight test vehicle will demonstrate an air-launched reusable vehicle capable of flight to speeds of Mach 8. The Lockheed-Martin X-33 flight test vehicle will expand the test envelope for critical technologies to flight speeds of Mach 15. A propulsion program to test the X-33 linear aerospike rocket engine using a NASA SR-71 high speed aircraft as a test bed is also discussed. The paper also describes the management and operational approaches that address the challenge of new cost-effective, reusable launch vehicle systems.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-20
... Permits for Reusable Suborbital Rockets AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice... Number: 2120-0722. Title: Experimental Permits for Reusable Suborbital Rockets. Form Numbers: There are... experimental permits for reusable suborbital rockets to authorize launches for the purpose of research and...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-21
... Permits for Reusable Suborbital Rockets AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice... INFORMATION: OMB Control Number: 2120-0722. Title: Experimental Permits for Reusable Suborbital Rockets. Form... experimental permits for reusable suborbital rockets to authorize launches for the purpose of research and...
Sterilization of reusable implant components: a pilot study.
Cain, J R; Mitchell, D L; Gillespie, J C
2000-12-01
The placement and restoration of dental implants require the use of numerous reusable instruments and components. The adequate sterilization of reusable instruments and components is essential to prevent cross contamination between patients. Sterilization usually is accomplished with single-use sterilization envelopes. A reusable sterilization vehicle would reduce costs as well as the waste generated in patient care. This study was designed to determine the efficacy of a 10-cc Pyrex test tube as a sterilization vehicle for reusable dental implant instruments and components. In this study, a reusable dental implant component was placed in a Pyrex test tube, along with a biologic test strip. A control biologic test strip was kept for each test tube. The test tube was closed with a cotton roll folded in half and placed in the opening. Twenty test tubes were prepared. five sets of 4 test tubes were placed in an autoclave in different locations with varying orientations. The autoclave completed a standard sterilization cycle. The biological monitoring service indicated that the biologic test strips in 100% of the test tubes were sterile, whereas the control strips were 100% nonsterile. A Pyrex test tube sealed with a cotton roll can serve as a sterilization vehicle for reusable dental implant instruments and components.
Is It Worth It? - the Economics of Reusable Space Transportation
NASA Technical Reports Server (NTRS)
Webb, Richard
2016-01-01
Over the past several decades billions of dollars have been invested by governments and private companies in the pursuit of lower cost access to space through earth-to-orbit (ETO) space transportation systems. Much of that investment has been focused on the development and operation of various forms of reusable transportation systems. From the Space Shuttle to current efforts by private commercial companies, the overarching belief of those making such investments has been that reusing system elements will be cheaper than utilizing expendable systems that involve throwing away costly engines, avionics, and other hardware with each flight. However, the view that reusable systems are ultimately a "better" approach to providing ETO transportation is not held universally by major stakeholders within the space transportation industry. While the technical feasibility of at least some degree of reusability has been demonstrated, there continues to be a sometimes lively debate over the merits and drawbacks of reusable versus expendable systems from an economic perspective. In summary, is it worth it? Based on our many years of direct involvement with the business aspects of several expendable and reusable transportation systems, it appears to us that much of the discussion surrounding reusability is hindered by a failure to clearly define and understand the financial and other metrics by which the financial "goodness" of a reusable or expandable approach is measured. As stakeholders, the different users and suppliers of space transportation have a varied set of criteria for determining the relative economic viability of alternative strategies, including reusability. Many different metrics have been used to measure the affordability of space transportation, such as dollars per payload pound (kilogram) to orbit, cost per flight, life cycle cost, net present value/internal rate of return, and many others. This paper will examine the key considerations that influence stakeholders as they make space transportation investment decisions, including primary metrics by which various stakeholders measure financial goodness and other factors that significantly shape decisions to invest in reusable or expendable systems. It must be noted at the outset that reusable systems take many forms and perform different transportation functions including, but not limited to, ETO payload delivery. The discussion in this paper is limited to the economics of ETO transportation systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Estevez, Luis; Reed, David; Nie, Zimin
We decorated the surfaces of graphite felts with some oxygen-containing functional groups, such as C-OH, O=C and HO-C=O. And the mole ratios and amounts of these functional groups were effectively adjusted on the graphite surface by a particular method. The catalytic effects of amounts and mole ratio of different kinds of functional groups on VRB electrode performances were investigated in detail.
Comparison of adsorption of Remazol Black B and Acidol Red on microporous activated carbon felt.
Donnaperna, L; Duclaux, L; Gadiou, R; Hirn, M-P; Merli, C; Pietrelli, L
2009-11-15
The adsorption of two anionic dyes, Remazol Black B (RB5) and Acidol Red 2BE-NW (AR42), onto a microporous activated carbon felt was investigated. The characterization of carbon surface chemistry by X-ray microanalysis, Boehm titrations, and pH-PZC measurements indicates that the surface oxygenated groups are mainly acidic. The rate of adsorption depends on the pH and the experimental data fit the intraparticle diffusion model. The pore size distribution obtained by DFT analysis shows that the mean pore size is close to 1nm, which indicates that a slow intraparticle diffusion process control the adsorption. The adsorption isotherms were measured for different pH values. The Khan and the Langmuir-Freundlich models lead to the best agreement with experimental data for RB5 and AR42, respectively. These isotherm simulations and the pH dependence of adsorption show that the adsorption capacity is mainly controlled by nondispersive electrostatic interactions for pH values below 4. The adsorption kinetics, the irreversibility of the process, and the influence of the pH indicate that the rate of adsorption in this microporous felt proceeds through two steps. The first one is fast and results from direct interaction of dye molecules with the external surface of the carbon material (which account for 10% of the whole surface area); in the second, slow step, the adsorption rate is controlled by the slow diffusion of dye molecules into the narrow micropores. The influence of temperature on the adsorption isotherms was studied and the thermodynamic parameters were obtained. They show that the process is spontaneous and exothermic.
Roughness Perception of Haptically Displayed Fractal Surfaces
NASA Technical Reports Server (NTRS)
Costa, Michael A.; Cutkosky, Mark R.; Lau, Sonie (Technical Monitor)
2000-01-01
Surface profiles were generated by a fractal algorithm and haptically rendered on a force feedback joystick, Subjects were asked to use the joystick to explore pairs of surfaces and report to the experimenter which of the surfaces they felt was rougher. Surfaces were characterized by their root mean square (RMS) amplitude and their fractal dimension. The most important factor affecting the perceived roughness of the fractal surfaces was the RMS amplitude of the surface. When comparing surfaces of fractal dimension 1.2-1.35 it was found that the fractal dimension was negatively correlated with perceived roughness.
Code of Federal Regulations, 2011 CFR
2011-01-01
... covering to which the pile, face, or outer surface is woven, tufted, hooked, knitted, or otherwise attached..., knitted, or felted into a wool product which, after having been used in any way by the ultimate consumer...
Comparative life cycle assessment of disposable and reusable laryngeal mask airways.
Eckelman, Matthew; Mosher, Margo; Gonzalez, Andres; Sherman, Jodi
2012-05-01
Growing awareness of the negative impacts from the practice of health care on the environment and public health calls for the routine inclusion of life cycle criteria into the decision-making process of device selection. Here we present a life cycle assessment of 2 laryngeal mask airways (LMAs), a one-time-use disposable Unique™ LMA and a 40-time-use reusable Classic™ LMA. In life cycle assessment, the basis of comparison is called the "functional unit." For this report, the functional unit of the disposable and reusable LMAs was taken to be maintenance of airway patency by 40 disposable LMAs or 40 uses of 1 reusable LMA. This was a cradle-to-grave study that included inputs and outputs for the manufacture, transport, use, and waste phases of the LMAs. The environmental impacts of the 2 LMAs were estimated using SimaPro life cycle assessment software and the Building for Environmental and Economic Sustainability impact assessment method. Sensitivity and simple life cycle cost analyses were conducted to aid in interpretation of the results. The reusable LMA was found to have a more favorable environmental profile than the disposable LMA as used at Yale New Haven Hospital. The most important sources of impacts for the disposable LMA were the production of polymers, packaging, and waste management, whereas for the reusable LMA, washing and sterilization dominated for most impact categories. The differences in environmental impacts between these devices strongly favor reusable devices. These benefits must be weighed against concerns regarding transmission of infection. Health care facilities can decrease their environmental impacts by using reusable LMAs, to a lesser extent by selecting disposable LMA models that are not made of certain plastics, and by ordering in bulk from local distributors. Certain practices would further reduce the environmental impacts of reusable LMAs, such as increasing the number of devices autoclaved in a single cycle to 10 (-25% GHG emissions) and improving the energy efficiency of the autoclaving machines by 10% (-8% GHG emissions). For both environmental and cost considerations, management and operating procedures should be put in place to ensure that reusable LMAs are not discarded prematurely.
Sonsmann, F K; Strunk, M; Gediga, K; John, C; Schliemann, S; Seyfarth, F; Elsner, P; Diepgen, T L; Kutz, G; John, S M
2014-05-01
To date, there are no legally binding requirements concerning product testing in cosmetics. This leads to various manufacturer-specific test methods and absent transparent information on skin cleansing products. A standardized in vivo test procedure for assessment of cleansing efficacy and corresponding barrier impairment by the cleaning process is needed, especially in the occupational context where repeated hand washing procedures may be performed at short intervals. For the standardization of the cleansing procedure, an Automated Cleansing Device (ACiD) was designed and evaluated. Different smooth washing surfaces of the equipment for ACiD (incl. goat hair, felt, felt covered with nitrile caps) were evaluated regarding their skin compatibility. ACiD allows an automated, fully standardized skin washing procedure. Felt covered with nitrile as washing surface of the rotating washing units leads to a homogenous cleansing result and does not cause detectable skin irritation, neither clinically nor as assessed by skin bioengineering methods (transepidermal water loss, chromametry). Automated Cleansing Device may be useful for standardized evaluation of the cleansing effectiveness and parallel assessment of the corresponding irritancy potential of industrial skin cleansers. This will allow objectifying efficacy and safety of industrial skin cleansers, thus enabling market transparency and facilitating rational choice of products. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
14 CFR 431.3 - Types of reusable launch vehicle mission licenses.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Types of reusable launch vehicle mission licenses. 431.3 Section 431.3 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION...) General § 431.3 Types of reusable launch vehicle mission licenses. (a) Mission-specific license. A mission...
14 CFR 431.9 - Issuance of a reusable launch vehicle mission license.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Issuance of a reusable launch vehicle mission license. 431.9 Section 431.9 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.9 Issuance of a reusable launch vehicle mission license. (a) The FAA issues...
14 CFR 431.3 - Types of reusable launch vehicle mission licenses.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Types of reusable launch vehicle mission licenses. 431.3 Section 431.3 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION...) General § 431.3 Types of reusable launch vehicle mission licenses. (a) Mission-specific license. A mission...
14 CFR 431.9 - Issuance of a reusable launch vehicle mission license.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Issuance of a reusable launch vehicle mission license. 431.9 Section 431.9 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.9 Issuance of a reusable launch vehicle mission license. (a) The FAA issues...
14 CFR 431.13 - Transfer of a reusable launch vehicle mission license.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Transfer of a reusable launch vehicle mission license. 431.13 Section 431.13 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.13 Transfer of a reusable launch vehicle mission license. (a) Only the FAA may...
14 CFR 431.13 - Transfer of a reusable launch vehicle mission license.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Transfer of a reusable launch vehicle mission license. 431.13 Section 431.13 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.13 Transfer of a reusable launch vehicle mission license. (a) Only the FAA may...
14 CFR 431.9 - Issuance of a reusable launch vehicle mission license.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Issuance of a reusable launch vehicle mission license. 431.9 Section 431.9 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.9 Issuance of a reusable launch vehicle mission license. (a) The FAA issues...
14 CFR 431.3 - Types of reusable launch vehicle mission licenses.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Types of reusable launch vehicle mission licenses. 431.3 Section 431.3 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION...) General § 431.3 Types of reusable launch vehicle mission licenses. (a) Mission-specific license. A mission...
14 CFR 431.13 - Transfer of a reusable launch vehicle mission license.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Transfer of a reusable launch vehicle mission license. 431.13 Section 431.13 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.13 Transfer of a reusable launch vehicle mission license. (a) Only the FAA may...
14 CFR 431.13 - Transfer of a reusable launch vehicle mission license.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Transfer of a reusable launch vehicle mission license. 431.13 Section 431.13 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.13 Transfer of a reusable launch vehicle mission license. (a) Only the FAA may...
14 CFR 431.3 - Types of reusable launch vehicle mission licenses.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Types of reusable launch vehicle mission licenses. 431.3 Section 431.3 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION...) General § 431.3 Types of reusable launch vehicle mission licenses. (a) Mission-specific license. A mission...
14 CFR 431.3 - Types of reusable launch vehicle mission licenses.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Types of reusable launch vehicle mission licenses. 431.3 Section 431.3 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION...) General § 431.3 Types of reusable launch vehicle mission licenses. (a) Mission-specific license. A mission...
14 CFR 431.13 - Transfer of a reusable launch vehicle mission license.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Transfer of a reusable launch vehicle mission license. 431.13 Section 431.13 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.13 Transfer of a reusable launch vehicle mission license. (a) Only the FAA may...
14 CFR 431.9 - Issuance of a reusable launch vehicle mission license.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Issuance of a reusable launch vehicle mission license. 431.9 Section 431.9 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.9 Issuance of a reusable launch vehicle mission license. (a) The FAA issues...
14 CFR 431.9 - Issuance of a reusable launch vehicle mission license.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Issuance of a reusable launch vehicle mission license. 431.9 Section 431.9 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... VEHICLE (RLV) General § 431.9 Issuance of a reusable launch vehicle mission license. (a) The FAA issues...
How dirty are your reusable water bottles?
NASA Astrophysics Data System (ADS)
Williams, S.
2017-12-01
Reusable water bottles are an environment-friendly option but may grow harmful bacteria if not washed regularly. To test whether washing habits affect bacterial growth, I swabbed 10 different plastic reusable bottles and counted colony growth after laboratory incubation. My results did not show a clear relationship between days since last wash and colony growth.
Support for life-cycle product reuse in NASA's SSE
NASA Technical Reports Server (NTRS)
Shotton, Charles
1989-01-01
The Software Support Environment (SSE) is a software factory for the production of Space Station Freedom Program operational software. The SSE is to be centrally developed and maintained and used to configure software production facilities in the field. The PRC product TTCQF provides for an automated qualification process and analysis of existing code that can be used for software reuse. The interrogation subsystem permits user queries of the reusable data and components which have been identified by an analyzer and qualified with associated metrics. The concept includes reuse of non-code life-cycle components such as requirements and designs. Possible types of reusable life-cycle components include templates, generics, and as-is items. Qualification of reusable elements requires analysis (separation of candidate components into primitives), qualification (evaluation of primitives for reusability according to reusability criteria) and loading (placing qualified elements into appropriate libraries). There can be different qualifications for different installations, methodologies, applications and components. Identifying reusable software and related components is labor-intensive and is best carried out as an integrated function of an SSE.
Evaluating the Ergonomics of Flexible Ureteroscopy.
Ludwig, Wesley W; Lee, Gyusung; Ziemba, Justin B; Ko, Joan S; Matlaga, Brian R
2017-10-01
To date, the ergonomics of flexible ureteroscopy (URS) have not been well described. We performed a study to assess the biomechanical stresses on urologists performing URS and to investigate the effect of ureteroscope type on these parameters. Electromyography (EMG) was used to quantify the activation level of muscle groups involved in URS. Surface EMG electrodes (Delsys, Boston, MA) were placed on the right and left thenar, flexor carpi ulnaris (FCU), extensor carpi ulnaris (ECU), biceps, triceps, and deltoid. Three endoscopes were studied: single-use digital (Boston Scientific LithoVue), reusable digital (Karl Storz Flex-X c ), and reusable fiber-optic (Karl Storz Flex-X 2 ). Each ureteroscope was used to perform a set sequence of navigation and procedural tasks in a training model. EMG data were processed and normalized to compare the maximum voluntary contractions between muscle groups. Cumulative muscular workload (CMW) and average muscular work per second (AWS) were used for comparative analysis. For navigational tasks, CMW and AWS were greatest for the ECU, followed in descending order by right and left thenar, FCU, biceps, deltoid, and triceps. For procedural tasks, CMW and AWS were greatest for the right thenar, followed in descending order by the left thenar, ECU, FCU, triceps, biceps, and deltoid. During navigational tasks, both LithoVue and Flex-X c had lower CMWs for every muscle group than Flex-X 2 (p < 0.05). LithoVue and Flex-X c had similar AWS and both were lower than Flex-X 2 for the right thenar, ECU, biceps, and deltoid activation (p < 0.05). During procedural tasks, both LithoVue and Flex-X c had lower CMWs and AWS for right and left thenar, ECU, and biceps than Flex-X 2 (p < 0.05). This study provides the first description of EMG-measured ergonomics of URS. Both the single-use and reusable digital ureteroscopes have similar profiles, and both have significantly better ergonomic metrics than the reusable fiber-optic ureteroscope.
Space Transportation Infrastructure Supported By Propellant Depots
NASA Technical Reports Server (NTRS)
Smitherman, David; Woodcock, Gordon
2011-01-01
A space transportation infrastructure is described that utilizes propellant depots to support all foreseeable missions in the Earth-Moon vicinity and deep space out to Mars. The infrastructure utilizes current expendable launch vehicles such as the Delta IV Heavy, Atlas V, and Falcon 9, for all crew, cargo, and propellant launches to orbit. Propellant launches are made to a Low-Earth-Orbit (LEO) Depot and an Earth-Moon Lagrange Point 1 (L1) Depot to support new reusable in-space transportation vehicles. The LEO Depot supports missions to Geosynchronous Earth Orbit (GEO) for satellite servicing, and to L1 for L1 Depot missions. The L1 Depot supports Lunar, Earth-Sun L2 (ESL2), Asteroid, and Mars missions. A Mars Orbital Depot is also described to support ongoing Mars missions. New concepts for vehicle designs are presented that can be launched on current 5-meter diameter expendable launch vehicles. These new reusable vehicle concepts include a LEO Depot, L1 Depot, and Mars Orbital Depot based on International Space Station (ISS) heritage hardware. The high-energy depots at L1 and Mars orbit are compatible with, but do not require, electric propulsion tug use for propellant and/or cargo delivery. New reusable in-space crew transportation vehicles include a Crew Transfer Vehicle (CTV) for crew transportation between the LEO Depot and the L1 Depot, a new reusable Lunar Lander for crew transportation between the L1 Depot and the lunar surface, and a Deep Space Habitat (DSH) to support crew missions from the L1 Depot to ESL2, Asteroid, and Mars destinations. A 6 meter diameter Mars lander concept is presented that can be launched without a fairing based on the Delta IV heavy Payload Planners Guide, which indicates feasibility of a 6.5 meter fairing. This lander would evolve to re-usable operations when propellant production is established on Mars. Figure 1 provides a summary of the possible missions this infrastructure can support. Summary mission profiles are presented for each primary mission capability. These profiles are the basis for propellant loads, numbers of vehicles/stages and launches for each mission capability. Data includes the number of launches required for each mission utilizing current expendable launch vehicle systems, and concluding remarks include ideas for reducing the number of launches through incorporation of heavy-lift launch vehicles, solar electric propulsion, and other transportation support concepts.
Reusable Launch Vehicle Attitude Control Using a Time-Varying Sliding Mode Control Technique
NASA Technical Reports Server (NTRS)
Shtessel, Yuri B.; Zhu, J. Jim; Daniels, Dan; Jackson, Scott (Technical Monitor)
2002-01-01
In this paper we present a time-varying sliding mode control (TVSMC) technique for reusable launch vehicle (RLV) attitude control in ascent and entry flight phases. In ascent flight the guidance commands Euler roll, pitch and yaw angles, and in entry flight it commands the aerodynamic angles of bank, attack and sideslip. The controller employs a body rate inner loop and the attitude outer loop, which are separated in time-scale by the singular perturbation principle. The novelty of the TVSMC is that both the sliding surface and the boundary layer dynamics can be varied in real time using the PD-eigenvalue assignment technique. This salient feature is used to cope with control command saturation and integrator windup in the presence of severe disturbance or control effector failure, which enhances the robustness and fault tolerance of the controller. The TV-SMC ascent and descent designs are currently being tested with high fidelity, 6-DOF dispersion simulations. The test results will be presented in the final version of this paper.
Universal and reusable virus deactivation system for respiratory protection
NASA Astrophysics Data System (ADS)
Quan, Fu-Shi; Rubino, Ilaria; Lee, Su-Hwa; Koch, Brendan; Choi, Hyo-Jick
2017-01-01
Aerosolized pathogens are a leading cause of respiratory infection and transmission. Currently used protective measures pose potential risk of primary/secondary infection and transmission. Here, we report the development of a universal, reusable virus deactivation system by functionalization of the main fibrous filtration unit of surgical mask with sodium chloride salt. The salt coating on the fiber surface dissolves upon exposure to virus aerosols and recrystallizes during drying, destroying the pathogens. When tested with tightly sealed sides, salt-coated filters showed remarkably higher filtration efficiency than conventional mask filtration layer, and 100% survival rate was observed in mice infected with virus penetrated through salt-coated filters. Viruses captured on salt-coated filters exhibited rapid infectivity loss compared to gradual decrease on bare filters. Salt-coated filters proved highly effective in deactivating influenza viruses regardless of subtypes and following storage in harsh environmental conditions. Our results can be applied in obtaining a broad-spectrum, airborne pathogen prevention device in preparation for epidemic and pandemic of respiratory diseases.
Universal and reusable virus deactivation system for respiratory protection
Quan, Fu-Shi; Rubino, Ilaria; Lee, Su-Hwa; Koch, Brendan; Choi, Hyo-Jick
2017-01-01
Aerosolized pathogens are a leading cause of respiratory infection and transmission. Currently used protective measures pose potential risk of primary/secondary infection and transmission. Here, we report the development of a universal, reusable virus deactivation system by functionalization of the main fibrous filtration unit of surgical mask with sodium chloride salt. The salt coating on the fiber surface dissolves upon exposure to virus aerosols and recrystallizes during drying, destroying the pathogens. When tested with tightly sealed sides, salt-coated filters showed remarkably higher filtration efficiency than conventional mask filtration layer, and 100% survival rate was observed in mice infected with virus penetrated through salt-coated filters. Viruses captured on salt-coated filters exhibited rapid infectivity loss compared to gradual decrease on bare filters. Salt-coated filters proved highly effective in deactivating influenza viruses regardless of subtypes and following storage in harsh environmental conditions. Our results can be applied in obtaining a broad-spectrum, airborne pathogen prevention device in preparation for epidemic and pandemic of respiratory diseases. PMID:28051158
Near-Optimal Re-Entry Trajectories for Reusable Launch Vehicles
NASA Technical Reports Server (NTRS)
Chou, H.-C.; Ardema, M. D.; Bowles, J. V.
1997-01-01
A near-optimal guidance law for the descent trajectory for earth orbit re-entry of a fully reusable single-stage-to-orbit pure rocket launch vehicle is derived. A methodology is developed to investigate using both bank angle and altitude as control variables and selecting parameters that maximize various performance functions. The method is based on the energy-state model of the aircraft equations of motion. The major task of this paper is to obtain optimal re-entry trajectories under a variety of performance goals: minimum time, minimum surface temperature, minimum heating, and maximum heading change; four classes of trajectories were investigated: no banking, optimal left turn banking, optimal right turn banking, and optimal bank chattering. The cost function is in general a weighted sum of all performance goals. In particular, the trade-off between minimizing heat load into the vehicle and maximizing cross range distance is investigated. The results show that the optimization methodology can be used to derive a wide variety of near-optimal trajectories.
3D-printed tracheoesophageal puncture and prosthesis placement simulator.
Barber, Samuel R; Kozin, Elliott D; Naunheim, Matthew R; Sethi, Rosh; Remenschneider, Aaron K; Deschler, Daniel G
A tracheoesophageal prosthesis (TEP) allows for speech after total laryngectomy. However, TEP placement is technically challenging, requiring a coordinated series of steps. Surgical simulators improve technical skills and reduce operative time. We hypothesize that a reusable 3-dimensional (3D)-printed TEP simulator will facilitate comprehension and rehearsal prior to actual procedures. The simulator was designed using Fusion360 (Autodesk, San Rafael, CA). Components were 3D-printed in-house using an Ultimaker 2+ (Ultimaker, Netherlands). Squid simulated the common tracheoesophageal wall. A Blom-Singer TEP (InHealth Technologies, Carpinteria, CA) replicated placement. Subjects watched an instructional video and completed pre- and post-simulation surveys. The simulator comprised 3D-printed parts: the esophageal lumen and superficial stoma. Squid was placed between components. Ten trainees participated. Significant differences existed between junior and senior residents with surveys regarding anatomy knowledge(p<0.05), technical details(p<0.01), and equipment setup(p<0.01). Subjects agreed that simulation felt accurate, and rehearsal raised confidence in future procedures. A 3D-printed TEP simulator is feasible for surgical training. Simulation involving multiple steps may accelerate technical skills and improve education. Copyright © 2017 Elsevier Inc. All rights reserved.
14 CFR 431.15 - Rights not conferred by a reusable launch vehicle mission license.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Rights not conferred by a reusable launch vehicle mission license. 431.15 Section 431.15 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION... LAUNCH VEHICLE (RLV) General § 431.15 Rights not conferred by a reusable launch vehicle mission license...
14 CFR 431.15 - Rights not conferred by a reusable launch vehicle mission license.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Rights not conferred by a reusable launch vehicle mission license. 431.15 Section 431.15 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION... LAUNCH VEHICLE (RLV) General § 431.15 Rights not conferred by a reusable launch vehicle mission license...
14 CFR 431.15 - Rights not conferred by a reusable launch vehicle mission license.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Rights not conferred by a reusable launch vehicle mission license. 431.15 Section 431.15 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION... LAUNCH VEHICLE (RLV) General § 431.15 Rights not conferred by a reusable launch vehicle mission license...
14 CFR 431.15 - Rights not conferred by a reusable launch vehicle mission license.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Rights not conferred by a reusable launch vehicle mission license. 431.15 Section 431.15 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION... LAUNCH VEHICLE (RLV) General § 431.15 Rights not conferred by a reusable launch vehicle mission license...
14 CFR 431.15 - Rights not conferred by a reusable launch vehicle mission license.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Rights not conferred by a reusable launch vehicle mission license. 431.15 Section 431.15 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION... LAUNCH VEHICLE (RLV) General § 431.15 Rights not conferred by a reusable launch vehicle mission license...
Methodology for Evaluating Quality and Reusability of Learning Objects
ERIC Educational Resources Information Center
Kurilovas, Eugenijus; Bireniene, Virginija; Serikoviene, Silvija
2011-01-01
The aim of the paper is to present the scientific model and several methods for the expert evaluation of quality of learning objects (LOs) paying especial attention to LOs reusability level. The activities of eQNet Quality Network for a European Learning Resource Exchange (LRE) aimed to improve reusability of LOs of European Schoolnet's LRE…
14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.
Code of Federal Regulations, 2010 CFR
2010-01-01
...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...
14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.
Code of Federal Regulations, 2013 CFR
2013-01-01
...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...
14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.
Code of Federal Regulations, 2012 CFR
2012-01-01
...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...
14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.
Code of Federal Regulations, 2011 CFR
2011-01-01
...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...
14 CFR 437.31 - Verification of operating area containment and key flight-safety event limitations.
Code of Federal Regulations, 2014 CFR
2014-01-01
...(a) to contain its reusable suborbital rocket's instantaneous impact point within an operating area... limits on the ability of the reusable suborbital rocket to leave the operating area; or (2) Abort... requirements of § 437.59 to conduct any key flight-safety event so that the reusable suborbital rocket's...
NASA Technical Reports Server (NTRS)
Morgan, Timothy E.
1995-01-01
The objective of the Reusable Software System (RSS) is to provide NASA Langley Research Center and its contractor personnel with a reusable software technology through the Internet. The RSS is easily accessible, provides information that is extractable, and the capability to submit information or data for the purpose of scientific research at NASA Langley Research Center within the Atmospheric Science Division.
Emotional labor actors: a latent profile analysis of emotional labor strategies.
Gabriel, Allison S; Daniels, Michael A; Diefendorff, James M; Greguras, Gary J
2015-05-01
Research on emotional labor focuses on how employees utilize 2 main regulation strategies-surface acting (i.e., faking one's felt emotions) and deep acting (i.e., attempting to feel required emotions)-to adhere to emotional expectations of their jobs. To date, researchers largely have considered how each strategy functions to predict outcomes in isolation. However, this variable-centered perspective ignores the possibility that there are subpopulations of employees who may differ in their combined use of surface and deep acting. To address this issue, we conducted 2 studies that examined surface acting and deep acting from a person-centered perspective. Using latent profile analysis, we identified 5 emotional labor profiles-non-actors, low actors, surface actors, deep actors, and regulators-and found that these actor profiles were distinguished by several emotional labor antecedents (positive affectivity, negative affectivity, display rules, customer orientation, and emotion demands-abilities fit) and differentially predicted employee outcomes (emotional exhaustion, job satisfaction, and felt inauthenticity). Our results reveal new insights into the nature of emotion regulation in emotional labor contexts and how different employees may characteristically use distinct combinations of emotion regulation strategies to manage their emotional expressions at work. (c) 2015 APA, all rights reserved.
Chen, Bingan; Zhong, Guofang; Oppenheimer, Pola Goldberg; Zhang, Can; Tornatzky, Hans; Esconjauregui, Santiago; Hofmann, Stephan; Robertson, John
2015-02-18
We have systematically studied the macroscopic adhesive properties of vertically aligned nanotube arrays with various packing density and roughness. Using a tensile setup in shear and normal adhesion, we find that there exists a maximum packing density for nanotube arrays to have adhesive properties. Too highly packed tubes do not offer intertube space for tube bending and side-wall contact to surfaces, thus exhibiting no adhesive properties. Likewise, we also show that the surface roughness of the arrays strongly influences the adhesion properties and the reusability of the tubes. Increasing the surface roughness of the array strengthens the adhesion in the normal direction, but weakens it in the shear direction. Altogether, these results allow progress toward mimicking the gecko's vertical mobility.
Differences in alarm events between disposable and reusable electrocardiography lead wires.
Albert, Nancy M; Murray, Terri; Bena, James F; Slifcak, Ellen; Roach, Joel D; Spence, Jackie; Burkle, Alicia
2015-01-01
Disposable electrocardiographic lead wires (ECG-LWs) may not be as durable as reusable ones. To examine differences in alarm events between disposable and reusable ECG-LWs. Two cardiac telemetry units were randomized to reusable ECG-LWs, and 2 units alternated between disposable and reusable ECG-LWs for 4 months. A remote monitoring team, blinded to ECG-LW type, assessed frequency and type of alarm events by using total counts and rates per 100 patient days. Event rates were compared by using generalized linear mixed-effect models for differences and noninferiority between wire types. In 1611 patients and 9385.5 patient days of ECG monitoring, patient characteristics were similar between groups. Rates of alarms for no telemetry, leads fail, or leads off were lower in disposable ECG-LWs (adjusted relative risk [95% CI], 0.71 [0.53-0.96]; noninferiority P < .001; superiority P = .03) and monitoring (artifact) alarms were significantly noninferior (adjusted relative risk [95% CI]: 0.88, [0.62-1.24], P = .02; superiority P = .44). No between-group differences existed in false or true crisis alarms. Disposable ECG-LWs were noninferior to reusable ECG-LWs for all false-alarm events (N [rate per 100 patient days], disposable 2029 [79.1] vs reusable 6673 [97.9]; adjusted relative risk [95% CI]: 0.81 [0.63-1.06], P = .002; superiority P = .12.) Disposable ECG-LWs with patented push-button design had superior performance in reducing alarms created by no telemetry, leads fail, or leads off and significant noninferiority in all false-alarm rates compared with reusable ECG-LWs. Fewer ECG alarms may save nurses time, decrease alarm fatigue, and improve patient safety. ©2015 American Association of Critical-Care Nurses.
Rollnick, M
1991-05-01
Both re-usable and disposable systems have their merits and problems. The disposable system, being fully integrated, appears to be steadily gaining market share compared with the re-usable system. Since its introduction, the success of the re-usable system has been limited by the use of pans not designed for automatic processing. Where the 'perfection' pan has been superseded by 'open' shaped receptacles and those used in commode chairs, cleaning effectiveness can be improved by a factor of 10. For this and other reasons, nursing involvement in the re-usable system can be high while the 'perfection' pan is in use. A work study exercise to compare nursing involvement in re-usable and disposable systems is under way. When selecting a human waste disposal system for any site, it is vital that all disciplines discuss and decide objectives. The equipment usage, space, site conditions, availability and quality of supplies (eg water, electricity), the costs of maintenance, nursing time and other expenditure must be considered. The disposable system is capable of high process rates (more than double that of the fastest re-usable system). Its capital cost is currently about 1,000 pounds less than an average re-usable system, but in the busiest wards, revenue costs may be higher. In such wards the space for disposable receptacle storage can be as much as five to ten times machine volume. The design of macerators is generally simpler (having less components) than washer-disinfectors. Monitoring and maintenance involvement are likewise expected to be lower, particularly in hospitals with modern drainage systems.(ABSTRACT TRUNCATED AT 250 WORDS)
Production Planning and Simulation for Reverse Supply Chain
NASA Astrophysics Data System (ADS)
Murayama, Takeshi; Yoda, Mitsunobu; Eguchi, Toru; Oba, Fuminori
This paper describes a production planning method for a reverse supply chain, in which a disassembly company takes reusable components from returned used products and supplies the reusable components for a product manufacturer. This method addresses the issue that the timings and quantities of returned products and reusable components obtained from them are unknown. This method first predicts the quantities of returned products and reusable components at each time period by using reliability models. Using the prediction result, the method performs production planning based on Material Requirements Planning (MRP). This method enables us to plan at each time period: the quantity of the products to be disassembled; the quantity of the reusable components to be used; and the quantity of the new components to be produced. The flow of the components and products through a forward and reverse supply chain is simulated to show the effectiveness of the method.
Reusable Component Model Development Approach for Parallel and Distributed Simulation
Zhu, Feng; Yao, Yiping; Chen, Huilong; Yao, Feng
2014-01-01
Model reuse is a key issue to be resolved in parallel and distributed simulation at present. However, component models built by different domain experts usually have diversiform interfaces, couple tightly, and bind with simulation platforms closely. As a result, they are difficult to be reused across different simulation platforms and applications. To address the problem, this paper first proposed a reusable component model framework. Based on this framework, then our reusable model development approach is elaborated, which contains two phases: (1) domain experts create simulation computational modules observing three principles to achieve their independence; (2) model developer encapsulates these simulation computational modules with six standard service interfaces to improve their reusability. The case study of a radar model indicates that the model developed using our approach has good reusability and it is easy to be used in different simulation platforms and applications. PMID:24729751
High efficiency replicated x-ray optics and fabrication method
Barbee, Jr., Troy W.; Lane, Stephen M.; Hoffman, Donald E.
2001-01-01
Replicated x-ray optics are fabricated by sputter deposition of reflecting layers on a super-polished reusable mandrel. The reflecting layers are strengthened by a supporting multilayer that results in stronger stress-relieved reflecting surfaces that do not deform during separation from the mandrel. The supporting multilayer enhances the ability to part the replica from the mandrel without degradation in surface roughness. The reflecting surfaces are comparable in smoothness to the mandrel surface. An outer layer is electrodeposited on the supporting multilayer. A parting layer may be deposited directly on the mandrel before the reflecting surface to facilitate removal of the layered, tubular optic device from the mandrel without deformation. The inner reflecting surface of the shell can be a single layer grazing reflection mirror or a resonant multilayer mirror. The resulting optics can be used in a wide variety of applications, including lithography, microscopy, radiography, tomography, and crystallography.
Liu, Lanhua; Zhou, Xiaohong; Lu, Yun; Shan, Didi; Xu, Bi; He, Miao; Shi, Hanchang; Qian, Yi
2017-11-15
The apparent increase in hormone-induced cancers and disorders of the reproductive tract has led to a growing demand for new technologies capable of screening xenoestrogens. We reported an estrogen receptor (ER)-based reusable fiber biosensor for facile screening estrogenic compounds in environment. The bioassay is based on the competition of xenoestrogens with 17β-estradiol (E 2 ) for binding to the recombinant receptor of human estrogen receptor α (hERα) protein, leaving E 2 free to bind to fluorophore-labeled anti-E 2 monoclonal antibody. Unbound anti-E 2 antibody then binds to the immobilized E 2 -protein conjugate on the fiber surface, and is detected by fluorescence emission induced by evanescent field. As expected, the stronger estrogenic activity of xenoestrogen would result in the weaker fluorescent signal. Three estrogen-agonist compounds, diethylstilbestrol (DES), 4-n-nonylphenol (NP) and 4-n-octylphenol (OP), were chosen as a paradigm for validation of this assay. The rank order of estrogenic potency determined by this biosensor was DES>OP>NP, which were consistent with the published results in numerous studies. Moreover, the E 2 -protein conjugate modified optical fiber was robust enough for over 300 sensing cycles with the signal recoveries ranging from 90% to 100%. In conclusion, the biosensor is reusable, reliable, portable and amenable to on-line operation, providing a facile, efficient and economical alternative to screen potential xenoestrogens in environment. Copyright © 2017 Elsevier B.V. All rights reserved.
Application of reusable PZT sensors for monitoring initial hydration of concrete
NASA Astrophysics Data System (ADS)
Sabet Divsholi, Bahador; Yang, Yaowen
2009-03-01
To increase the efficiency of in-situ casting or precast of concrete, determining the optimal time of demolding is very important for concrete suppliers. In the first few hours after mixing, the fresh concrete gradually achieves solid properties with reasonable compressive strength. Due to different type and amount of cementitious materials, concrete additives (e.g. retarders) and curing temperature, different rates of hardening are expected. In addition, some other factors like the quality of the cementitious materials further increase the uncertainty in determining appropriate time for demolding of concrete. Electro-mechanical impedance (EMI) based lead zirconate titanate (PZT) sensors have been used for damage detection and structural identification for various engineering structures. In this work, a reusable PZT sensor for monitoring initial hydration of concrete is developed, where a piece of PZT is bonded to a piece of metal with two bolts tightened inside of the holes drilled in the metal. An impedance analyzer is used to acquire the signature of this reusable sensor. During the concrete casting, the bolts and the bottom surface of the metal is set to penetrate part of the fresh concrete. At different stages of the first 48 hours after casting, the PZT signatures are acquired. A statistical analysis technique is employed to associate the change in concrete strength with the changes in the PZT admittance signatures. The results show that the developed sensor is able to effectively monitor the initial hydration of concrete, and can be detached from the concrete for future use.
NASA Technical Reports Server (NTRS)
Marshall, B. A.; Marroquin, J.
1984-01-01
In order to support analysis of the STS-6 advanced flexible reusable surface insulation (AFRSI) anomaly, data were obtained for aerodynamic and aeroacoustic environments in affected areas of the orbiter. Data are presented in tabular form.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-13
... Reusable Suborbital Rockets at the Mojave Air and Space Port AGENCY: Federal Aviation Administration (FAA... of SpaceShipTwo Reusable Suborbital Rockets at the Mojave Air and Space Port. The Draft EA was... licenses to operate SpaceShipTwo Reusable Suborbital Rockets and WhiteKnightTwo carrier aircraft at the...
Long-term/strategic scenario for reusable booster stages
NASA Astrophysics Data System (ADS)
Sippel, Martin; Manfletti, Chiara; Burkhardt, Holger
2006-02-01
This paper describes the final design status of a partially reusable space transportation system which has been under study for five years within the German future launcher technology research program ASTRA. It consists of dual booster stages, which are attached to an advanced expendable core. The design of the reference liquid fly-back boosters (LFBB) is focused on LOX/LH2 propellant and a future advanced gas-generator cycle rocket motor. The preliminary design study was performed in close cooperation between DLR and the German space industry. The paper's first part describes recent progress in the design of this reusable booster stage. The second part of the paper assesses a long-term, strategic scenario of the reusable stage's operation. The general idea is the gradual evolution of the above mentioned basic fly-back booster vehicle into three space transportation systems performing different tasks: Reusable First Stage for a small launcher application, successive development to a fully reusable TSTO, and booster for a super-heavy-lift rocket to support an ambitious space flight program like manned Mars missions. The assessment addresses questions of technical sanity, preliminary sizing and performance issues and, where applicable, examines alternative options.
Integrated circuits, and design and manufacture thereof
Auracher, Stefan; Pribbernow, Claus; Hils, Andreas
2006-04-18
A representation of a macro for an integrated circuit layout. The representation may define sub-circuit cells of a module. The module may have a predefined functionality. The sub-circuit cells may include at least one reusable circuit cell. The reusable circuit cell may be configured such that when the predefined functionality of the module is not used, the reusable circuit cell is available for re-use.
A Prospective Randomized Study Comparing Disposable with Reusable Blades for a Morcellator Device.
Becker, Benedikt; Orywal, Ann Katrin; Hausmann, Teresa; Gross, Andreas J; Netsch, Christopher
2017-03-01
Transurethral enucleation of the prostate for the management of benign prostatic obstruction (BPO) involves two steps: the enucleation and morcellation procedure. The aim of our study was to assess the efficacy of a morcellator device using disposable and reusable blades with different settings of morcellation speed. A prospective randomized study was initiated for patients with symptomatic BPO undergoing Thulium laser enucleation of the prostate. Mechanical tissue morcellation was performed using the Piranha™ morcellator (R. Wolf, Knittlingen, Germany) with disposable or reusable blades at 850 (n = 24) or 1500 revolutions per minute (rpm) (n = 24). Patient characteristics, intraoperative complications, and the morcellation rate (g/min) were recorded. Data are expressed as median and interquartile range (IQR). Forty-eight patients were randomized using disposable (n = 24) or reusable blades (n = 24). For reusable blades, the morcellation rate did not increase when changing the morcellation speed from 850 to 1500 rpm (5 vs 4.53 g/min, p = 0.843). The morcellation rate increased significantly when changing the morcellation speed from 850 to 1500 rpm using single-use blades (4.77 vs 10 g/min, p ≤ 0.014). The morcellation rate was not different at 850 rpm between reusable and single-use blades (5 vs 4.77 g/min, p = 0.671). Conversely, the morcellation rate was significantly different at 1500 rpm between reusable and single-use blades (4.53 vs 10 g/min, p ≤ 0.017). The total morcellation rate (at 850 and 1500 rpm) was significantly increased using single-use blades compared to reusable blades (7.67 vs 4.8 g/min, p ≤ 0.026). Interestingly, enucleated weight (g) and the morcellation rate (g/min) correlated inversely using single-use blades at 1500 rpm (r = -0.742, p ≤ 0.004). Only one superficial bladder injury occurred at 1500 rpm, which needed no further interventions. The Piranha morcellator facilitates efficient tissue removal with single-use and reusable blades. Disposable morcellator blades increase tissue removal significantly at 1500 rpm.
NASA Technical Reports Server (NTRS)
2004-01-01
KENNEDY SPACE CENTER, FLA. -- In the Orbiter Processing Facility, workers remove the Rudder Speed Brake panel on the vertical tail of the orbiter Atlantis. The Rudder Speed Brake is being removed for inspection and maintenance prior to Return to Flight. The vertical tail consists of a structural fin surface made of aluminum, the Rudder Speed Brake surface, a tip and a lower trailing edge. The rudder splits into two halves to serve as a speed brake. The vertical tail and Rudder Speed Brake are covered with a reusable thermal protection system. The Rudder Speed Brake is used to guide and slow the Shuttle as it comes in for a landing.
Closeup of F-15B Flight Test Fixture (FTF) with X-33 Thermal Protection Systems (TPS)
NASA Technical Reports Server (NTRS)
1998-01-01
A close up of the Flight Test Fixture II, mounted on the underside of the F-15B Aerodynamic Flight Facility aircraft. The Thermal Protection System (TPS)samples, which included metallic Inconel tiles, soft Advanced Flexible Reusable Surface Insulation tiles, and sealing materials, were attached to the forward-left side position of the test fixture. In-flight video from the aircraft's on-board video system, as well as chase aircraft photos and video footage, documented the condition of the TPS during flights. Surface pressures over the TPS was measured by thermocouples contained in instrumentation 'islands,' to document shear and shock loads.
NASA Technical Reports Server (NTRS)
Houser, J. F.; Runciman, W. H.
1971-01-01
Experimental aerodynamic investigations were made in the Grumman 36-inch hypersonic wind tunnel on a .00435 scale model of the H-32 reusable space shuttle booster. The objectives of the test were to determine the static stability characteristics and control surface effectiveness at hypersonic speeds. Data were taken at M = 8.12 over a range of angles of attack between -5 and 85 deg at beta = 0 deg and over a range of side slip angles between -10 and 10 deg at alpha = 0 and 70 deg. Six component balance data and base-cavity pressure data were recorded.
Closeup of F-15B Flight Test Fixture (FTF) with X-33 Thermal Protection Systems (TPS)
1998-05-14
A close up of the Flight Test Fixture II, mounted on the underside of the F-15B Aerodynamic Flight Facility aircraft. The Thermal Protection System (TPS) samples, which included metallic Inconel tiles, soft Advanced Flexible Reusable Surface Insulation tiles, and sealing materials, were attached to the forward-left side position of the test fixture. In-flight video from the aircraft's on-board video system, as well as chase aircraft photos and video footage, documented the condition of the TPS during flights. Surface pressures over the TPS was measured by thermocouples contained in instrumentation "islands," to document shear and shock loads.
Experimental evaluation of joint designs for a space-shuttle orbiter ablative leading edge
NASA Technical Reports Server (NTRS)
Tompkins, S. S.; Kabana, W. P.
1975-01-01
The thermal performance of two types of ablative leading-edge joints for a space-shuttle orbiter were tested and evaluated. Chordwise joints between ablative leading-edge segments, and spanwise joints between ablative leading-edge segments and reusable surface insulation tiles were exposed to simulated shuttle heating environments. The data show that the thermal performance of models with chordwise joints to be as good as jointless models in simulated ascent-heating and orbital cold-soak environments. The suggestion is made for additional work on the joint seals, and, in particular, on the effects of heat-induced seal-material surface irregularities on the local flow.
Structural active cooling applications for the Space Shuttle.
NASA Technical Reports Server (NTRS)
Masek, R. V.; Niblock, G. A.; Huneidi, F.
1972-01-01
Analytic and experimental studies have been conducted to evaluate a number of active cooling approaches to structural thermal protection for the Space Shuttle. The primary emphasis was directed toward the thermal protection system. Trade study results are presented for various heat shield material and TPS arrangements. Both metallic and reusable surface insulation (RSI) concepts were considered. Active systems heat sinks consisted of hydrogen, phase change materials, and expendable water. If consideration is given only to controlling the surface temperature, passive TPS was found to provide the most efficient system. Use of active cooling which incorporates some interior temperature control made the thermally less efficient RSI system more attractive.
NASA Technical Reports Server (NTRS)
2004-01-01
KENNEDY SPACE CENTER, FLA. -- A Rudder Speed Brake Actuator is being removed from the orbiter Atlantis for shipment to the vendor for inspection. An actuator is a motor that moves the tail rudder back and forth to help steer it during landing and brake its speed. The vertical tail consists of a structural fin surface made of aluminum, the Rudder Speed Brake surface, a tip and a lower trailing edge. The rudder splits into two halves to serve as a speed brake. The vertical tail and Rudder Speed Brake are covered with a reusable thermal protection system. Atlantis is undergoing maintenance and inspection in the Orbiter Processing Facility for a future mission.
NASA Technical Reports Server (NTRS)
2004-01-01
KENNEDY SPACE CENTER, FLA. -- A Rudder Speed Brake Actuator is being removed from the orbiter Atlantis for shipment to the vendor for inspection. An actuator is a motor that moves the tail rudder back and forth to help steer it during landing and brake its speed. The vertical tail consists of a structural fin surface made of aluminum, the Rudder Speed Brake surface, a tip and a lower trailing edge. The rudder splits into two halves to serve as a speed brake. The vertical tail and Rudder Speed Brake are covered with a reusable thermal protection system. Atlantis is undergoing maintenance and inspection in the Orbiter Processing Facility for a future mission.
NASA Astrophysics Data System (ADS)
Barrocas, B.; Nunes, C. D.; Carvalho, M. L.; Monteiro, O. C.
2016-11-01
In this work, titanate nanotubes were modified with silver nanoparticles to produce new nanocomposite materials with enhanced photocatalytic activity for phenol removal. The TNTs were produced using a hydrothermal approach and, after being submitted to an Ag+ exchange process, metallic Ag nanoparticles were obtained over the nanotubes surface. The prepared materials were structural, morphological and optical characterized by X-ray powder diffraction, micro X-ray fluorescence, transmission electron microscopy, diffused reflectance spectroscopy and X-ray photoelectron spectroscopy. The characterization results indicate that Ag+ was immobilized not only in the nanotubes external surface but mainly in the TiO6 interlayers space. The application of this new nanocomposite material on photocatalytic degradation of pollutants was investigated. First, the evaluation of hydroxyl radical formation, using the terephthalic acid as a probe was studied. The photocatalytic activity of the sensitized materials for phenol degradation was afterwards evaluated. The results show that the nanocomposite sample is the best catalyst, achieving 98.0% photodegradation efficiency of a 0.2 mM phenol solution within 20 min under UV-vis radiation. The reusability of the prepared samples as photocatalysts was evaluated in four successive degradation assays, using fresh phenol solutions. The sensitized sample demonstrated excellent catalytic reusability ability, without loss of photochemical stability. The structural and morphological characterization during these experiments revealed no modifications on the nanotubes morphology but a continuous increase on the Ag nanoparticles, in number and size, with the irradiation time. A mechanism for this continuous growth of the Ag nanoparticles, together with the phenol catalytic photodegradation, over the nanotubes surface, is proposed and discussed.
Wang, Jhe-Yi; Su, Ya-Ling; Wu, Bo-Hao; Cheng, Shu-Hua
2016-01-15
The toxicity of bisphenol A (BPA) has attracted considerable attention, and the reported electrochemical sensors for BPA need further improvement in reusability due to serious surface fouling. In this study, a composite film is designed aiming to provide both an accurate and repeatable platform for BPA determination. The conducting poly(3,4-ethylenedioxythiophene) film (PEDOT) and ionic liquid 1-butyl-3-methylimidazolium bromide (BMIMBr) were modified onto screen-printed carbon electrodes (SPCE) by electropolymerization and drop/spin methods, respectively. The surface characteristics of the composite film were characterized by field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS) and surface water contact angle experiments. The composite film-modified electrodes exhibited a linear response to BPA in the range of 0.1-500µM in pH 7.0 phosphate buffer solution (PBS) under optimized flow-injection amperometry. The method sensitivity and detection limit (S/N=3) were 0.2661μA μM(-1) (2.419μA μM(-1)cm(-2)) and 0.02µM, respectively. A relative standard deviation of 1.95% was obtained for 77 successive measurements of 10µM BPA, and the repeatability outperformed previously reported work. The proposed method was applied to detect BPA released from plastic water bottles using the standard addition method, and satisfactory recoveries were obtained. The electrochemical assay was validated by comparison with the chromatographic method, and the results showed good agreement between the two methods. Copyright © 2015 Elsevier B.V. All rights reserved.
Reusable Cryogenic Tank VHM Using Fiber Optic Distributed Sensing Technology
NASA Technical Reports Server (NTRS)
Bodan-Sanders, Patricia; Bouvier, Carl
1998-01-01
The reusable oxygen and hydrogen tanks are key systems for both the X-33 (sub-scale, sub-orbital technology demonstrator) and the commercial Reusable Launch Vehicle (RLV). The backbone of the X-33 Reusable Cryogenic Tank Vehicle Health Management (VHM) system lies in the optical network of distributed strain temperature and hydrogen sensors. This network of fiber sensors will create a global strain and temperature map for monitoring the health of the tank structure, cryogenic insulation, and Thermal Protection System. Lockheed Martin (Sanders and LMMSS) and NASA Langley have developed this sensor technology for the X-33 and have addressed several technical issues such as fiber bonding and laser performance in this harsh environment.
International aerospaceplane efforts
NASA Technical Reports Server (NTRS)
Lindley, Charles A.
1992-01-01
Although the U.S. began the first reusable space booster effort in the late 1950's, it is no longer an exclusive field. All of the technologically advanced nations, and several groups of nations, have one or more reusable booster efforts in progress. A listing of the entries in the field is presented. The list is somewhat misleading, because it includes both fully reusable and partially reusable boosters, both manned and unmanned, and both flight test and operational proposals. Additionally, not all of the projects are funded, and only a few of the projects will survive. The most likely candidates are the following: France/ESA, Germany/ESA, Great Britain/ESA/(USSR), USSR(past), and Japan. A discussion of the preceding projects is provided.
2nd Generation Reusable Launch Vehicle Potential Commercial Development Scenarios
NASA Technical Reports Server (NTRS)
Creech, Stephen D.; Rogacki, John R. (Technical Monitor)
2001-01-01
The presentation will discuss potential commercial development scenarios for a Second Generation Reusable Launch Vehicle. The analysis of potential scenarios will include commercial rates of return, government return on investment, and market considerations. The presentation will include policy considerations in addition to analysis of Second Generation Reusable Launch Vehicle economics. The data discussed is being developed as a part of NASA's Second Generation Reusable Launch Vehicle Program, for consideration as potential scenarios for enabling a next generation system. Material will include potential scenarios not previously considered by NASA or presented at other conferences. Candidate paper has not been presented at a previous meeting, and conference attendance of the author has been approved by NASA.
Huang, Shufeng; Wan, Zhenping; Zou, Shuiping
2018-03-20
A novel sintered cutting stainless steel fiber felt with internal channels (SCSSFFC) composed of a stainless-steel fiber skeleton, three-dimensional interconnected porous structure and multiple circular microchannels is developed. SCSSFFC has a jagged and rough surface morphology and possesses a high specific surface area, which is approximately 2.4 times larger than that of the sintered bundle-drawing stainless steel fiber felt with internal channels (SBDSSFFC) and is expected to enhance adhesive strength. The sol-gel and wet impregnation methods are adopted to prepare SCSSFFC with an Al₂O₃ coating (SCSSFFC/Al₂O₃). The adhesive strength of SCSSFFC/Al₂O₃ is investigated using ultrasonic vibration and thermal shock tests. The experimental results indicate that the weight loss rate of the Al₂O₃ coating has a 4.2% and 8.42% reduction compared with those of SBDSSFFCs based on ultrasonic vibration and thermal shock tests. In addition, the permeability of SCSSFFC/Al₂O₃ is investigated based on forced liquid flow tests. The experimental results show that the permeability and inertial coefficients of SCSSFFC/Al₂O₃ are mainly affected by the coating rate, porosity and open ratio; however, the internal microchannel diameter has little influence. It is also found that SCSSFFC/Al₂O₃ yields superior permeability, as well as inertial coefficients compared with those of other porous materials reported in the literature.
Penteado, Eduardo D; Fernandez-Marchante, Carmen M; Zaiat, Marcelo; Gonzalez, Ernesto R; Rodrigo, Manuel A
2017-06-01
The aim of this work was to evaluate three carbon materials as anodes in microbial fuel cells (MFCs), clarifying their influence on the generation of electricity and on the treatability of winery wastewater, a highly organic-loaded waste. The electrode materials tested were carbon felt, carbon cloth and carbon paper and they were used at the same time as anode and cathode in the tests. The MFC equipped with carbon felt reached the highest voltage and power (72 mV and 420 mW m -2 , respectively), while the lowest values were observed when carbon paper was used as electrode (0.2 mV and 8.37·10 -6 mW m -2 , respectively). Chemical oxygen demand (COD) removal from the wastewater was observed to depend on the electrode material, as well. When carbon felt was used, the MFC showed the highest average organic matter consumption rate (650 mg COD L -1 d -1 ), whereas by using carbon paper the rate decreased to 270 mg COD L -1 d -1 . Therefore, both electricity generation and organic matter removal are strongly related not to the chemical composition of the electrode (which was graphite carbon in the three electrodes), but to its surface features and, consequently, to the amount of biomass adhered to the electrode surface.
NASA Astrophysics Data System (ADS)
Wei, L.; Zhao, T. S.; Zeng, L.; Zeng, Y. K.; Jiang, H. R.
2017-02-01
In this work, we prepare a highly catalytic and stabilized titanium nitride (TiN) nanowire array-decorated graphite felt electrode for all vanadium redox flow batteries (VRFBs). Free-standing TiN nanowires are synthesized by a two-step process, in which TiO2 nanowires are first grown onto the surface of graphite felt via a seed-assisted hydrothermal method and then converted to TiN through nitridation reaction. When applied to VRFBs, the prepared electrode enables the electrolyte utilization and energy efficiency to be 73.9% and 77.4% at a high current density of 300 mA cm-2, which are correspondingly 43.3% and 15.4% higher than that of battery assembled with a pristine electrode. More impressively, the present battery exhibits good stability and high capacity retention during the cycle test. The superior performance is ascribed to the significant improvement in the electrochemical kinetics and enlarged active sites toward V3+/V2+ redox reaction.
Commercially Available Activated Carbon Fiber Felt Enables Efficient Solar Steam Generation.
Li, Haoran; He, Yurong; Hu, Yanwei; Wang, Xinzhi
2018-03-21
Sun-driven steam generation is now possible and has the potential to help meet future energy needs. Current technologies often use solar condensers to increase solar irradiance. More recently, a technology for solar steam generation that uses heated surface water and low optical concentration is reported. In this work, a commercially available activated carbon fiber felt is used to generate steam efficiently under one sun illumination. The evaporation rate and solar conversion efficiency reach 1.22 kg m -2 h -1 and 79.4%, respectively. The local temperature of the evaporator with a floating activated carbon fiber felt reaches 48 °C. Apart from the high absorptivity (about 94%) of the material, the evaporation performance is enhanced thanks to the well-developed pores for improved water supply and steam escape and the low thermal conductivity, which enables reduced bulk water temperature increase. This study helps to find a promising material for solar steam generation using a water evaporator that can be produced economically (∼6 $/m 2 ) with long-term stability.
W18O49 nanowires assembled on carbon felt for application to supercapacitors
NASA Astrophysics Data System (ADS)
Jung, Jinjoo; Kim, Do Hyung
2018-03-01
For supercapacitor applications, W18O49 nanowires have been extensively grown on graphitic carbon felt using a facile solvothermal method. The diameter and length of the nanowires are about 7 and 300 nm, respectively. The nanowires consist of monoclinic W18O49 grown along the [010] direction, as shown by TEM and XRD analyses. The W18O49 nanowires, assembled on carbon felt, exhibit a high capacity of 588.33 F/g at a current density of 1 A/g together with an excellent cycle performance, and a low internal resistance during the electrochemical tests. This outstanding performance may originate from the three-dimensional porous nanostructure of these W18O49 nanowires, which leads to a reduction in the resistance and fast reaction kinetics due to the high specific surface area and electrolyte accessibility. Furthermore, sufficient oxygen deficiencies of the substoichiometric tungsten oxide can also contribute to the electrochemical activity, which can be confirmed by comparison of CV and EIS data with WO3 nanowires.
Cheung, Francis Y L; Lun, Vivian Miu-Chi
2015-01-01
This study examined the association between emotional labor and organizational citizenship behavior (OCB) and the mediation of work engagement in this relationship. A total of 264 teachers in Mainland China were recruited for this study. Bivariate correlation showed that both deep acting and the expression of naturally felt emotion were positively related to the two dimensions of OCB, namely, OCB toward the individual (OCBI) and OCB toward the organization (OCBO), whereas surface acting was not related to the OCB dimensions. Work engagement was also positively associated with both OCB dimensions. Regression results showed that work engagement partially mediated the relation between deep acting and OCBO, and that between the expression of naturally felt emotion and OCBI. Work engagement also fully mediated the association between deep acting and OCBI, and that between the expression of naturally felt emotion and OCBO. In light of these findings, strategies that encourage employees to display emotions consistent with their inner experience were discussed.
Surface dose measurement for helical tomotherapy.
Snir, Jonatan A; Mosalaei, Homeira; Jordan, Kevin; Yartsev, Slav
2011-06-01
To compare the surface dose measurements made by different dosimeters for the helical tomotherapy (HT) plan in the case of the target close to the surface. Surface dose measurements in different points for the HT plan to deliver 2 Gy to the planning target volume (PTV) at 5 mm below the surface of the cylindrical phantom were performed by radiochromic films, single use metal oxide semiconductor field-effect transistor (MOSFET) dosimeters, silicon IVD QED diode, and optically stimulated luminescence (OSL) dosimeters. The measured doses by all dosimeters were within 12 +/- 8% difference of each other. Radiochromic films, EBT, and EBT2, provide high spatial resolution, although it is difficult to get accurate measurements of dose. Both the OSL and QED measured similar dose to that of the MOSFET detectors. The QED dosimeter is promising as a reusable on-line wireless dosimeter, while the OSL dosimeters are easier to use, require minimum setup time and are very precise.
Hospital information system: reusability, designing, modelling, recommendations for implementing.
Huet, B
1998-01-01
The aims of this paper are to precise some essential conditions for building reuse models for hospital information systems (HIS) and to present an application for hospital clinical laboratories. Reusability is a general trend in software, however reuse can involve a more or less part of design, classes, programs; consequently, a project involving reusability must be precisely defined. In the introduction it is seen trends in software, the stakes of reuse models for HIS and the special use case constituted with a HIS. The main three parts of this paper are: 1) Designing a reuse model (which objects are common to several information systems?) 2) A reuse model for hospital clinical laboratories (a genspec object model is presented for all laboratories: biochemistry, bacteriology, parasitology, pharmacology, ...) 3) Recommendations for generating plug-compatible software components (a reuse model can be implemented as a framework, concrete factors that increase reusability are presented). In conclusion reusability is a subtle exercise of which project must be previously and carefully defined.
Close up view under the Orbiter Discovery in the Vehicle ...
Close up view under the Orbiter Discovery in the Vehicle Assembly Building at NASA's Kennedy Space Center. The view is under the port wing looking forward toward the main fuselage showing a detail of the landing gear and landing gear door. This view also shows the patterns of worn and replaced High-temperature Reusable Surface Insulation tiles. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX
Ascent Aerodynamic Pressure Distributions on WB001
NASA Technical Reports Server (NTRS)
Vu, B.; Ruf, J.; Canabal, F.; Brunty, J.
1996-01-01
To support the reusable launch vehicle concept study, the aerodynamic data and surface pressure for WB001 were predicted using three computational fluid dynamic (CFD) codes at several flow conditions between code to code and code to aerodynamic database as well as available experimental data. A set of particular solutions have been selected and recommended for use in preliminary conceptual designs. These computational fluid dynamic (CFD) results have also been provided to the structure group for wing loading analysis.
NASA Astrophysics Data System (ADS)
Li, Hui; Li, Gui; Li, Zhiping; Lu, Cuimei; Li, Yanan; Tan, Xianzhou
2013-01-01
Surface imprinting chlorogenic acid (CGA) on nano-TiO2 particles as sacrificial support material was successfully performed by using 4-vinylpyridine (4-VP) as functional monomer to obtain a hollow CGA-imprinted polymer (H-MIP1). Fourier transmission infrared spectrometry (FTIR) and scanning electron microscopy (SEM) were utilized for structurally characterizing the polymers obtained and adsorption dynamics and thermodynamic behavior investigated according to different models. Binding selectivity, adsorption capacity and the reusability for this H-MIP1 were also evaluated. This hollow CGA imprinted polymer shows rapid binding dynamics and higher binding capability toward the template molecules. The pseudo first-order kinetic model was shown best to describe the binding process of CGA on the H-MIP1 and Langmuir isotherm model best to fit the experimental adsorption isotherm data. Through adsorption isotherms at different temperatures, thermodynamic parameter values were obtained. Selectivity coefficients for the H-MIP1 toward the template were 2.209, 3.213, 1.746 and 2.353 relative to CA, VA, PCA and GA, respectively. This H-MIP1 was also indicated with a good imprint effect and a high capability to capture CGA from methanol extract of Eucommia ulmoides (E. ulmoides) leaves. Additionally, a good reusability for this imprinted polymer was exhibited during repeated adsorption-desorption use.
PRE_X Programme: Aerothermodynamic Objectives and Aeroshape Definition for in Flight Experiments
NASA Astrophysics Data System (ADS)
Lambert, O.; Tribot, J.-P.; Saint-Cloud, F.
2002-01-01
As the expendable launch vehicles (ELV) are limited in their trend to lower costs, the reusability (Reusable Launch Vehicle, RLV) could be the way to make drastic step. By the year 2001, CNES proposed through the ANGEL phase 1 programme to preprare the required technical maturity before that RLV's become alternatives to ELV's. In such way, system ,propulsion, ground based demonstrations, aero-thermo-dynamics as well as in flight experimentation are planned. This paper is focused on the aero-thermo-dynamics (ATD) and in flight demonstration activities with emphasis on the better understanding of ATD problems emerging from past programmes among them shock wave transitionnal boundary layer interaction on surface control, boundary layer transition, local aerothermodynamic effects, gas- surface interaction, catalycity, base flow prediction,...In order to minimize as small as possible the management risk a first generation of vehicle dubbed Pre_X is designed to validate technological choices and to have as soon as possible re-entry data to calibrate the various tools involved in the future RLV definition. In addition, the main requirement for PRE_X aeroshape definition and the two different design approaches considered by Dassault Aviation and EADS-LV are discussed. Then, the more promising concept for the PRE_X application is presented. Finally, the current status of the ATD activities is given as well as the perspectives.
Behnajady, Mohammad A; Dadkhah, Hojjat; Eskandarloo, Hamed
2018-04-01
In this study, a horizontally rotating disc recirculated (HRDR) photoreactor equipped with two UV lamps (6 W) was designed and fabricated for photocatalytic removal of p-nitrophenol (PNP). Photocatalyst (TiO 2 ) nanoparticles were immobilized onto a high-density polyethylene (HDPE) disc, and PNP containing solution was allowed to flow (flow rate of 310 mL min -1 ) in radial direction along the surface of the rotating disc illuminated with UV light. The efficiency of direct photolysis and photocatalysis and the effect of rotating speed on the removal of PNP were studied in the HRDR photoreactor. It was found that TiO 2 -P25 nanoparticles are needed for the effective removal of PNP and there was an optimum rotating speed (450 rpm) for the efficient performance of the HRDR photoreactor. Then effects of operational variables on the removal efficiency were optimized using response surface methodology. The results showed that the predicted values of removal efficiency are consistent with experimental results with an R 2 of 0.9656. Optimization results showed that maximum removal percent (82.6%) was achieved in the HRDR photoreactor at the optimum operational conditions. Finally, the reusability of the HRDR photoreactor was evaluated and the results showed high reusability and stability without any significant decrease in the photocatalytic removal efficiency.
Yuan, Bo; Yin, Xiao-Qian; Liu, Xiao-Qin; Li, Xing-Yang; Sun, Lin-Bing
2016-06-29
Much attention has been paid to metal-organic frameworks (MOFs) due to their large surface areas, tunable functionality, and diverse structure. Nevertheless, most reported MOFs show poor hydrothermal stability, which seriously hinders their applications. Here a strategy is adopted to tailor the properties of MOFs by means of incorporating carboxyl-functionalized natural clay attapulgite (ATP) into HKUST-1, a well-known MOF. A new type of hybrid material was thus fabricated from the hybridization of HKUST-1 and ATP. Our results indicated that the hydrothermal stability of the MOFs as well as the catalytic performance was apparently improved. The frameworks of HKUST-1 were severely destroyed after hydrothermal treatment (hot water vapor, 60 °C), while that of the hybrid materials was maintained. For the hybrid materials containing 8.4 wt % of ATP, the surface area reached 1302 m(2)·g(-1) and was even higher than that of pristine HKUST-1 (1245 m(2)·g(-1)). In the ring-opening of styrene oxide, the conversion reached 98.9% at only 20 min under catalysis from the hybrid material, which was obviously higher than that over pristine HKUST-1 (80.9%). Moreover, the hybrid materials showed excellent reusability and the catalytic activity was recoverable without loss after six cycles. Our materials provide promising candidates for heterogeneous catalysis owing to the good catalytic activity and reusability.
Trajectory Approaches for Launching Hypersonic Flight Tests (Preprint)
2014-08-01
This paper presents some approaches toward designing trajectories for hypersonic testing at up to Mach 10 speed using a reusable rocket -powered first...Program to Optimize Simulated Trajectories (POST) code to look at different ways of flying to Mach 10 with a reusable first stage rocket . These trajectories...are good starting points for how to setup a trajectory simulation to meet hypersonic testing needs. 15. SUBJECT TERMS responsive and reusable rocket
Software Library: A Reusable Software Issue.
1984-06-01
On reverse aide it neceeary aid Identify by block number) Software Library; Program Library; Reusability; Generator 20 ABSTRACT (Cmlnue on revere... Software Library. A particular example of the Software Library, the Program Library, is described as a prototype of a reusable library. A hierarchical... programming libraries are described. Finally, non code products in the Software Library are discussed. Accesson Fo NTIS R~jS DrrC TA Availability Codes 0
Aeroheating Predictions for X-34 Using an Inviscid-Boundary Layer Method
NASA Technical Reports Server (NTRS)
Riley, Christopher J.; Kleb, William L.; Alter, Steven J.
1998-01-01
Radiative equilibrium surface temperatures and surface heating rates from a combined inviscid-boundary layer method are presented for the X-34 Reusable Launch Vehicle for several points along the hypersonic descent portion of its trajectory. Inviscid, perfect-gas solutions are generated with the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA) and the Data-Parallel Lower-Upper Relaxation (DPLUR) code. Surface temperatures and heating rates are then computed using the Langley Approximate Three-Dimensional Convective Heating (LATCH) engineering code employing both laminar and turbulent flow models. The combined inviscid-boundary layer method provides accurate predictions of surface temperatures over most of the vehicle and requires much less computational effort than a Navier-Stokes code. This enables the generation of a more thorough aerothermal database which is necessary to design the thermal protection system and specify the vehicle's flight limits.
Hennegan, Julie; Dolan, Catherine; Wu, Maryalice; Scott, Linda; Montgomery, Paul
2016-12-07
Governments, multinational organisations, and charities have commenced the distribution of sanitary products to address current deficits in girls' menstrual management. The few effectiveness studies conducted have focused on health and education outcomes but have failed to provide quantitative assessment of girls' preferences, experiences of absorbents, and comfort. Objectives of the study were, first, to quantitatively describe girls' experiences with, and ratings of reliability and acceptability of different menstrual absorbents. Second, to compare ratings of freely-provided reusable pads (AFRIpads) to other existing methods of menstrual management. Finally, to assess differences in self-reported freedom of activity during menses according to menstrual absorbent. Cross-sectional, secondary analysis of data from the final survey of a controlled trial of reusable sanitary padand puberty education provision was undertaken. Participants were 205 menstruating schoolgirls from eight schools in rural Uganda. 72 girls who reported using the intervention-provided reusable pads were compared to those using existing improvised methods (predominately new or old cloth). Schoolgirls using reusable pads provided significantly higher ratings of perceived absorbent reliability across activities, less difficulties changing absorbents, and less disgust with cleaning absorbents. There were no significant differences in reports of outside garment soiling (OR 1.00 95%CI 0.51-1.99), or odour (0.84 95%CI 0.40-1.74) during the last menstrual period. When girls were asked if menstruation caused them to miss daily activities there were no differences between those using reusable pads and those using other existing methods. However, when asked about activities avoided during menstruation, those using reusable pads participated less in physical sports, working in the field, fetching water, and cooking. Reusable pads were rated favourably. This translated into some benefits for self-reported involvement in daily activities, although reports of actual soiling and missing activities due to menstruation did not differ. More research is needed comparing the impact of menstrual absorbents on girls' daily activities, and validating outcome measures for menstrual management research.
Mager, R; Kurosch, M; Höfner, T; Frees, S; Haferkamp, A; Neisius, A
2018-01-22
The purpose of this study is to analyze clinical outcomes and costs of single-use flexible ureterorenoscopes in comparison with reusable flexible ureterorenoscopes in a tertiary referral center. Prospectively, 68 flexible ureterorenoscopies utilizing reusable (Flex-X2S, Flex-X C , Karl Storz) and 68 applying single-use flexible ureterorenoscopes (LithoVue, Boston Scientific) were collected. Clinical outcome parameters such as overall success rate, complication rates according to Clavien-Dindo, operation time and radiation exposure time were measured. Cost analysis was based on purchase costs and recurrent costs for repair and reprocessing divided by number of procedures. In each group 68 procedures were available for evaluation. In 91% of reusable and 88% of single-use ureterorenoscopies stone disease was treated with a mean stone burden of 101 ± 226 and 90 ± 244 mm 2 and lower pole involvement in 47 and 41%, respectively (p > 0.05). Comparing clinical outcomes of reusable vs. single-use instruments revealed no significant difference for overall success rates (81 vs. 87%), stone-free rates (82 vs. 85%), operation time (76.2 ± 46.8 vs. 76.8 ± 40.2 min), radiation exposure time (3.83 ± 3.15 vs. 3.93 ± 4.43 min) and complication rates (7 vs. 17%) (p > 0.05). A wide range of repair and purchase costs resulted in total to $1212-$1743 per procedure for reusable ureterorenoscopy whereas price of single-use ureterorenoscopy was $1300-$3180 per procedure. The current work provided evidence for equal clinical effectiveness of reusable and single-use flexible ureterorenoscopes. Partially overlapping ranges of costs for single-use and reusable scopes stress the importance to precisely know the expenses and caseload when negotiating purchase prices, repair prices and warranty conditions.
Leveillee, Raymond J; Kelly, Emily Fell
2016-01-01
Since the development of the first flexible ureteroscope, in 1964, technological advances in image quality, flexibility, and deflection have led to the development of the first single-use digital flexible ureteroscope, LithoVue™ (Boston Scientific, Marlborough, MA). With respect to reusable fiber-optic and now digital ureteroscopes, there is an initial capital cost of several thousand dollars (USD) as well as, controversy regarding durability, the cost of repairs and the burdensome reprocessing steps of ureteroscopy. The single-use LithoVue eliminates the need for costly repairs, the occurrence of unpredictable performance, and procedural delays. Renal stones located in the lower pole of the kidney can be extremely challenging as extreme deflections of greater than 160° are difficult to maintain and are often further compromised when using stone treatment tools, such as laser fibers and baskets. This case describes an initial use of the LithoVue digital disposable ureteroscope in the effective treatment of lower pole calculi using a 365 μm holmium laser fiber. A 35-year-old female, with a medical history significant for chronic bacteriuria, and recurrent symptomatic culture proven urinary tract infections, underwent localization studies. Retrograde ureteropyelography demonstrated two calcifications adjoining, measuring a total of 1.4 cm, overlying the left renal shadow. Urine aspirated yielded clinically significant, >100,000, Escherichia coli and Streptococcus anginosus bacteriuria, which was felt to be originating from the left lower calix. This case used the newly FDA-approved LithoVue flexible disposable ureteroscope. The two stones were seen using the ureteroscope passed through an ureteral access sheath in the lower pole calix. A 365 μm holmium laser fiber was inserted into the ureteroscope and advanced toward the stones. There was no loss of deflection as the ureteroscope performed reproducibly. The laser was used for more than 4000 pulses at 15 W, producing mucoid debris and fragments. A 1.9F nitinol basket was, then, used to extract the fragments, and the patient was rendered stone free. Treatment success was confirmed by plain abdominal film obtained 1 week after stent removal. The LithoVue system single-use digital flexible ureteroscope provides an economical advantage over both reusable digital and fiber-optic ureteroscopes. The LithoVue system uses the enhanced image resolution of the digital complementary metal oxide semiconductor imager, similar to other reusable digital ureteroscopes, while maintaining the small ureteroscope size of a flexible fiber-optic ureteroscope, allowing for consistent and effective lower pole access. Deflection characteristics are maintained even when thicker laser fibers are passed through the working channel.
Development of an external ceramic insulation for the space shuttle orbiter
NASA Technical Reports Server (NTRS)
Tanzilli, R. A. (Editor)
1972-01-01
The development and evaluation of a family of reusable external insulation systems for use on the space shuttle orbiter is discussed. The material development and evaluation activities are described. Additional information is provided on the development of an analytical micromechanical model of the reusable insulation and the development of techniques for reducing the heat transfer. Design data on reusable insulation systems and test techniques used for design data generation are included.
NASA KSC/AFRL Reusable Booster System (RBS) Concept of Operations (ConOps)
NASA Technical Reports Server (NTRS)
Zeno, Dnany; Mosteller, Ted; McCleskey, Carey; Jhnson, Robert; Hopkins, Jason; Miller, Thomas
2010-01-01
This slide presentation reviews the study and findings of the study on the Concept of Operations (ConOps) for Reusable Booster System (RBS) centering on rapid turnaround and launch of a two-stage partially reusable payload delivery system (i.e., 8 hours between launches). The study was to develop rapid ground processing (aircraft like concepts) and identify areas for follow-on study, technology needs, and proof-of-concept demonstrations.
Advanced High Temperature Structural Seals
NASA Technical Reports Server (NTRS)
Newquist, Charles W.; Verzemnieks, Juris; Keller, Peter C.; Shorey, Mark W.; Steinetz, Bruce (Technical Monitor)
2000-01-01
This program addresses the development of high temperature structural seals for control surfaces for a new generation of small reusable launch vehicles. Successful development will contribute significantly to the mission goal of reducing launch cost for small, 200 to 300 lb payloads. Development of high temperature seals is mission enabling. For instance, ineffective control surface seals can result in high temperature (3100 F) flows in the elevon area exceeding structural material limits. Longer sealing life will allow use for many missions before replacement, contributing to the reduction of hardware, operation and launch costs. During the first phase of this program the existing launch vehicle control surface sealing concepts were reviewed, the aerothermal environment for a high temperature seal design was analyzed and a mock up of an arc-jet test fixture for evaluating seal concepts was fabricated.
Zhang, Xiuli; Martens, Dieter; Krämer, Petra M; Kettrup, Antonius A; Liang, Xinmiao
2006-01-13
An immunosorbent was fabricated by encapsulation of monoclonal anti-isoproturon antibodies in sol-gel matrix. The immunosorbent-based loading, rinsing and eluting processes were optimized. Based on these optimizations, the sol-gel immunosorbent (SG-IS) selectively extracted isoproturon from an artificial mixture of 68 pesticides. In addition to this high selectivity, the SG-IS proved to be reusable. The SG-IS was combined with liquid chromatography-tandem mass spectrometry (LC-MS-MS) to determine isoproturon in surface water, and the linear range was up to 2.2 microg/l with correlation coefficient higher than 0.99 and relative standard deviation (RSD) lower than 5% (n=8). The limit of quantitation (LOQ) for 25-ml surface water sample was 5 ng/l.
Choi, Dong Yun; Heo, Ki Joon; Kang, Juhee; An, Eun Jeong; Jung, Soo-Ho; Lee, Byung Uk; Lee, Hye Moon; Jung, Jae Hee
2018-06-05
Here, we introduce a reusable bifunctional polyester/aluminum (PET/Al) air filter for the high efficiency simultaneous capture and inactivation of airborne microorganisms. Both bacteria of Escherichia coli and Staphylococcus epidermidis were collected on the PET/Al filter with a high efficiency rate (∼99.99%) via the electrostatic interactions between the charged bacteria and fibers without sacrificing pressure drop. The PET/Al filter experienced a pressure drop approximately 10 times lower per thickness compared with a commercial high-efficiency particulate air filter. As the Al nanograins grew on the fibers, the antimicrobial activity against airborne E. coli and S. epidermidis improved to ∼94.8% and ∼96.9%, respectively, due to the reinforced hydrophobicity and surface roughness of the filter. Moreover, the capture and antimicrobial performances were stably maintained during a cyclic washing test of the PET/Al filter, indicative of its reusability. The PET/Al filter shows great potential for use in energy-efficient bioaerosol control systems suitable for indoor environments. Copyright © 2018 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Stewart, D. A.; Goldstein, H. E.; Leiser, D. B. (Inventor)
1983-01-01
A high temperature stable and solar radiation stable thermal control coating is described which is useful either as such, applied directly to a member to be protected, or applied as a coating on a re-usable surface insulation (RSI). It has a base coat layer and an overlay glass layer. The base coat layer has a high emittance, and the overlay layer is formed from discrete, but sintered together glass particles to give the overlay layer a high scattering coefficient. The resulting two-layer space and thermal control coating has an absorptivity-to-emissivity ratio of less than or equal to 0.4 at room temperature, with an emittance of 0.8 at 1200 F. It is capable of exposure to either solar radiation or temperatures as high as 2000 F without significant degradation. When used as a coating on a silica substrate to give an RSI structure, the coatings of this invention show significantly less reduction in emittance after long term convective heating and less residual strain than prior art coatings for RSI structures.
Sadeghi, Saman; Liang, Vincent; Cheung, Shilin; Woo, Suh; Wu, Curtis; Ly, Jimmy; Deng, Yuliang; Eddings, Mark; van Dam, R. Michael
2015-01-01
A brass-platinum electrochemical micro flow cell was developed to extract [18F]fluoride from an aqueous solution and release it into an organic based solution, suitable for subsequent radio-synthesis, in a fast and reliable manner. This cell does not suffer electrode erosion and is thus reusable while operating faster by enabling increased voltages. By optimizing temperature, trapping and release potentials, flow rates, and electrode materials, an overall [18F]fluoride trapping and release efficiency of 84±5% (n=7) was achieved. X-ray photoelectron spectroscopy (XPS) was used to analyze electrode surfaces of various metal-metal systems and the findings were correlated with the performance of the electrochemical cell. To demonstrate the reactivity of the released [18F]fluoride, the cell was coupled to a flow-through reactor and automated synthesis of [18F]FDG with a repeatable decay-corrected yield of 56±4% (n=4) was completed in <15 min. A multi-human dose of 5.92 GBq [18F]FDG was also demonstrated. PMID:23474380
The IXV experience, from the mission conception to the flight results
NASA Astrophysics Data System (ADS)
Tumino, G.; Mancuso, S.; Gallego, J.-M.; Dussy, S.; Preaud, J.-P.; Di Vita, G.; Brunner, P.
2016-07-01
The atmospheric re-entry domain is a cornerstone of a wide range of space applications, ranging from reusable launcher stages developments, robotic planetary exploration, human space flight, to innovative applications such as reusable research platforms for in orbit validation of multiple space applications technologies. The Intermediate experimental Vehicle (IXV) is an advanced demonstrator which has performed in-flight experimentation of atmospheric re-entry enabling systems and technologies aspects, with significant advancements on Europe's previous flight experiences, consolidating Europe's autonomous position in the strategic field of atmospheric re-entry. The IXV mission objectives were the design, development, manufacturing, assembling and on-ground to in-flight verification of an autonomous European lifting and aerodynamically controlled reentry system, integrating critical re-entry technologies at system level. Among such critical technologies of interest, special attention was paid to aerodynamic and aerothermodynamics experimentation, including advanced instrumentation for aerothermodynamics phenomena investigations, thermal protections and hot-structures, guidance, navigation and flight control through combined jets and aerodynamic surfaces (i.e. flaps), in particular focusing on the technologies integration at system level for flight, successfully performed on February 11th, 2015.
NASA Technical Reports Server (NTRS)
Raj, Sai V.; Robinson, Raymond C.; Ghosn, Louis J.
2005-01-01
The design of the next generation of reusable launch vehicles calls for using GRCop-84 copper alloy liners based on a composition1 invented at the NASA Glenn Research Center: Cu-8(at.%)Cr-4%Nb. Many of the properties of this alloy have been shown to be far superior to those of other conventional copper alloys, such as NARloy-Z. Despite this considerable advantage, it is expected that GRCop-84 will suffer from some type of environmental degradation depending on the type of rocket fuel utilized. In a liquid hydrogen (LH2), liquid oxygen (LO2) booster engine, copper alloys undergo repeated cycles of oxidation of the copper matrix and subsequent reduction of the copper oxide, a process termed "blanching". Blanching results in increased surface roughness and poor heat-transfer capabilities, local hot spots, decreased engine performance, and premature failure of the liner material. This environmental degradation coupled with the effects of thermomechanical stresses, creep, and high thermal gradients can distort the cooling channel severely, ultimately leading to its failure.
Technology demonstration for reusable launchers
NASA Astrophysics Data System (ADS)
Baiocco, P.; Bonnal, Ch.
2016-03-01
Reusable launchers have been studied under CNES contracts for more than 30 years, with early concepts such as STS-2000 or Oriflamme, more recently with very significant efforts devoted to Liquid Fly Back Boosters as with the Bargouzin project led with Tsniimash, TSTO with the Everest concept studied by Airbus-DS as prime contractor or the RFS Reusable First Stage concept of a large first stage associated to a cryotechnic second stage. These investigations, summarized in the first part of the paper, enabled CNES to identify clearly the technology requirements associated to reusability, as well as cost efficiency through detailed non-recurring costs and mission costs analysis. In parallel, CNES set in place development logic for sub-systems and equipment based on demonstrators, hardware test benches enabling maturation of technologies up to a TRL such that an actual development can be decided with limited risk. This philosophy has been applied so far to a large number of cases, such as TPTech and TPX for Hydrogen turbo pump, GGPX as demonstrator of innovative gas generator, HX demonstrator of modern cryotechnic upper stage with a dozen of different objectives (Thermal Protection, 20K Helium storage, measurements …). This virtuous approach, "learn as you test", is currently applied in the phased approach towards scaled down reusable booster stage, whose possibility to be used as first stage of a microlaunch vehicle is under investigation. The selected technologies allow paving the way towards reusable booster stages for Ariane 6 evolutions or main reusable stage for a further generation of heavy launchers. The paper describes the logic behind this project, together with the demonstration objectives set for the various sub-systems as well as operations.
A Reusable Lunar Shuttlecraft (RLS): A systems study
NASA Technical Reports Server (NTRS)
1973-01-01
A study effort to conceive and design a reusable lunar space vehicle system was conducted at a university. The purpose of the program was to expose students to the problems faced by other disciplines in the design of a complete vehicle system. The subjects investigated are: (1) objectives, feasibility, and cost of reusable lunar shuttlecraft, (2) trajectory analysis, (3) guidance and navigation, (4) communication system, (5) propulsion system, (6) electrical power system, and (7) landing gear design.
Ada (Trademark) Reusability Guidelines.
1985-04-01
generators. Neighbors discusses another approach to reusable software using models. He describes a particular modeling technique using the Draco System ...experience with the Draco system . Is Fx~~~~flP7 7. 4 .~-’ b.r SECTION 4 DESIGN GUIDEUiNES As noted earlier, reusability is first and foremost a design issue...to be reused in another system that had a different type of physical data storage device, only this layer needs to be changed to deal with the new
Vozzola, Eric; Overcash, Michael; Griffing, Evan
2018-04-11
Isolation gowns serve a critical role in infection control by protecting healthcare workers, visitors, and patients from the transfer of microorganisms and body fluids. The decision of whether to use a reusable or disposable garment system is a selection process based on factors including sustainability, barrier effectiveness, cost, and comfort. Environmental sustainability is increasingly being used in the decision-making process. Life cycle assessment is the most comprehensive and widely used tool used to evaluate environmental performance. The environmental impacts of market-representative reusable and disposable isolation gown systems were compared using standard life cycle assessment procedures. The basis of comparison was 1,000 isolation gown uses in a healthcare setting. The scope included the manufacture, use, and end-of-life stages of the gown systems. At the healthcare facility, compared to the disposable gown system, the reusable gown system showed a 28% reduction in energy consumption, a 30% reduction in greenhouse gas emissions, a 41% reduction in blue water consumption, and a 93% reduction in solid waste generation. Selecting reusable garment systems may result in significant environmental benefits compared to selecting disposable garment systems. By selecting reusable isolation gowns, healthcare facilities can add these quantitative benefits directly to their sustainability scorecards. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Payload Performance Analysis for a Reusable Two-Stage-to-Orbit Vehicle
NASA Technical Reports Server (NTRS)
Tartabini, Paul V.; Beaty, James R.; Lepsch, Roger A.; Gilbert, Michael G.
2015-01-01
This paper investigates a unique approach in the development of a reusable launch vehicle where, instead of designing the vehicle to be reusable from its inception, as was done for the Space Shuttle, an expendable two stage launch vehicle is evolved over time into a reusable launch vehicle. To accomplish this objective, each stage is made reusable by adding the systems necessary to perform functions such as thermal protection and landing, without significantly altering the primary subsystems and outer mold line of the original expendable vehicle. In addition, some of the propellant normally used for ascent is used instead for additional propulsive maneuvers after staging in order to return both stages to the launch site, keep loads within acceptable limits and perform a soft landing. This paper presents a performance analysis that was performed to investigate the feasibility of this approach by quantifying the reduction in payload capability of the original expendable launch vehicle after accounting for the mass additions, trajectory changes and increased propellant requirements necessary for reusability. Results show that it is feasible to return both stages to the launch site with a positive payload capability equal to approximately 50 percent of an equivalent expendable launch vehicle. Further discussion examines the ability to return a crew/cargo capsule to the launch site and presents technical challenges that would have to be overcome.
2011-12-01
of residuals versus iteration number. “ Intermit ” and “retheta” are turbulence parameters for turbulence intermittency and . 42 ix Figure 4-7 – Wall...is based on the fact that “the flow‐field adapts at a very fast rate to changes in the free stream conditions as the vehicle is accelerating. This...4‐6 – Example of residuals versus iteration number. “ Intermit ” and “retheta” are turbulence parameters for turbulence intermittency and
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Jue; Zeng, Min, E-mail: min-zeng@buaa.edu.cn, E-mail: rhyu@buaa.edu.cn; Dong, Hangrong
Flower-like Fe{sub 3}O{sub 4}/Bi{sub 2}MoO{sub 6} has been prepared via a facile two-step thermosynthesis method. The composite displays high photocatalytic activity in Rhodamine B decomposition under visible light irradiation. Bi{sub 2}MoO{sub 6} with flower-like structure that has high specific surface area guarantees excellent photocatalytic performance. Fe{sub 3}O{sub 4} retards electron-hole recombination that contributes to photocatalytic property. Further, the stable composite exhibits remarkable reusability due to the incorporation of magnetic particle.
NASA Technical Reports Server (NTRS)
Christensen, H. E.; Kipp, H. W.
1974-01-01
Wind tunnel tests were conducted to determine the aerodynamic heating created by gaps in the reusable surface insulation (RSI) thermal protection system (TPS) for the space shuttle. The effects of various parameters of the RSI on convective heating characteristics are described. The wind tunnel tests provided a data base for accurate assessment of gap heating. Analysis and correlation of the data provide methods for predicting heating in the RSI gaps on the space shuttle.
Simultaneous Luminescence Pressure and Temperature Mapping
NASA Technical Reports Server (NTRS)
Buck, Gregory M. (Inventor)
1998-01-01
A simultaneous luminescence pressure and temperature mapping system is developed including improved dye application techniques for surface temperature and pressure measurements from 5 torr to 1000 torr with possible upgrade to from 0.5 torr to several atmospheres with improved camera resolution. Adsorbed perylene dye on slip-cast silica is pressure (oxygen) sensitive and reusable to relatively high temperatures (-150 C). Adsorbed luminescence has an approximately linear color shift with temperature, which can be used for independent temperature mapping and brightness pressure calibration with temperature.
Performance of LI-1542 Reusable Surface Insulation System in a Hypersonic Stream
1974-04-01
differential pressure loading across the panel. Facility The tests were conducted in the Langley 8-foot high-temperature "’!structures tunnel ( HTST ...is too long to be simulated in the relatively short test time of the 8-foot HTST ; therefore, the radiant-heat apparatus is used in sequence with the... HTST . Impact of these minute particles caused extensive crater damage to the tiles. A series of photos is shown in figure 20 to illustrate the
Double layered tailorable advanced blanket insulation
NASA Technical Reports Server (NTRS)
Falstrup, D.
1983-01-01
An advanced flexible reusable surface insulation material for future space shuttle flights was investigated. A conventional fly shuttle loom with special modifications to weave an integral double layer triangular core fabric from quartz yarn was used. Two types of insulating material were inserted into the cells of the fabric, and a procedure to accomplish this was developed. The program is follow up of a program in which single layer rectangular cell core fabrics are woven and a single type of insulating material was inserted into the cells.
Simultaneous Luminescence Pressure and Temperature Mapping System
NASA Technical Reports Server (NTRS)
Buck, Gregory M. (Inventor)
1995-01-01
A simultaneous luminescence pressure and temperature mapping system is developed including improved dye application techniques for surface temperature and pressure measurements from 5 torr to 1000 torr with possible upgrade to from 0.5 torr to several atmospheres with improved camera resolution. Adsorbed perylene dye on slip-cast silica is pressure (oxygen) sensitive and reusable to relatively high temperatures (approximately 150 C). Adsorbed luminescence has an approximately linear color shift with temperature, which can be used for independent temperature mapping and brightness pressure calibration with temperature.
NASA Astrophysics Data System (ADS)
Derr, Igor; Bruns, Michael; Langner, Joachim; Fetyan, Abdulmonem; Melke, Julia; Roth, Christina
2016-09-01
Electrochemical degradation (ED) of carbon felt electrodes was investigated by cycling of a flow through all-vanadium redox flow battery (VRFB) and conducting half-cell measurements with two reference electrodes inside the test bench. ED was detected using half-cell and full-cell electrochemical impedance spectroscopy (EIS) at different states of charge (SOC). Reversing the polarity of the battery to recover cell performance was performed with little success. Renewing the electrolyte after a certain amount of cycles restored the capacity of the battery. X-ray photoelectron spectroscopy (XPS) reveals that the amount of surface functional increases by more than a factor of 3 for the negative side as well as for the positive side. Scanning electron microscope (SEM) images show a peeling of the fiber surface after cycling the felts, which leads to a loss of electrochemically active surface area (ECSA). Long term cycling shows that ED has a stronger impact on the negative half-cell [V(II)/V(III)] than the positive half-cell [V(IV)/V(V)] and that the negative half-cell is the rate-determining half-cell for the VRFB.
14 CFR 437.57 - Operating area containment.
Code of Federal Regulations, 2012 CFR
2012-01-01
... containment. (a) During each permitted flight, a permittee must contain its reusable suborbital rocket's..., railway traffic, or waterborne vessel traffic. (c) The FAA may prohibit a reusable suborbital rocket's...
14 CFR 437.57 - Operating area containment.
Code of Federal Regulations, 2014 CFR
2014-01-01
... containment. (a) During each permitted flight, a permittee must contain its reusable suborbital rocket's..., railway traffic, or waterborne vessel traffic. (c) The FAA may prohibit a reusable suborbital rocket's...
14 CFR 437.57 - Operating area containment.
Code of Federal Regulations, 2013 CFR
2013-01-01
... containment. (a) During each permitted flight, a permittee must contain its reusable suborbital rocket's..., railway traffic, or waterborne vessel traffic. (c) The FAA may prohibit a reusable suborbital rocket's...
14 CFR 437.57 - Operating area containment.
Code of Federal Regulations, 2010 CFR
2010-01-01
... containment. (a) During each permitted flight, a permittee must contain its reusable suborbital rocket's..., railway traffic, or waterborne vessel traffic. (c) The FAA may prohibit a reusable suborbital rocket's...
14 CFR 437.57 - Operating area containment.
Code of Federal Regulations, 2011 CFR
2011-01-01
... containment. (a) During each permitted flight, a permittee must contain its reusable suborbital rocket's..., railway traffic, or waterborne vessel traffic. (c) The FAA may prohibit a reusable suborbital rocket's...
NASA Technical Reports Server (NTRS)
Olds, John R.; Cowart, Kris
2001-01-01
A method for integrating Aeroheating analysis into conceptual reusable launch vehicle (RLV) design is presented in this thesis. This process allows for faster turn-around time to converge a RLV design through the advent of designing an optimized thermal protection system (TPS). It consists of the coupling and automation of four computer software packages: MINIVER, TPSX, TCAT, and ADS. MINIVER is an Aeroheating code that produces centerline radiation equilibrium temperatures, convective heating rates, and heat loads over simplified vehicle geometries. These include flat plates and swept cylinders that model wings and leading edges, respectively. TPSX is a NASA Ames material properties database that is available on the World Wide Web. The newly developed Thermal Calculation Analysis Tool (TCAT) uses finite difference methods to carry out a transient in-depth 1-D conduction analysis over the center mold line of the vehicle. This is used along with the Automated Design Synthesis (ADS) code to correctly size the vehicle's thermal protection system (TPS). The numerical optimizer ADS uses algorithms that solve constrained and unconstrained design problems. The resulting outputs for this process are TPS material types, unit thicknesses, and acreage percentages. TCAT was developed for several purposes. First, it provides a means to calculate the transient in-depth conduction seen by the surface of the TPS material that protects a vehicle during ascent and reentry. Along with the in-depth conduction, radiation from the surface of the material is calculated along with the temperatures at the backface and interior parts of the TPS material. Secondly, TCAT contributes added speed and automation to the overall design process. Another motivation in the development of TCAT is optimization. In some vehicles, the TPS accounts for a high percentage of the overall vehicle dry weight. Optimizing the weight of the TPS will thereby lower the percentage of the dry weight accounted for by the TPS. Also, this will lower the cost of the TPS and the overall cost of the vehicle.
Mechanical analysis of confectioning flaw of refractory alloy honeycomb sandwich structure
NASA Astrophysics Data System (ADS)
He, Xiaodong; Kong, Xianghao; Shi, Liping; Li, Mingwei
2009-03-01
Thermal protection system is one of the key technology of reusable launch vehicle (RLV). After C/C and ceramic-matrix composite used in space orbiter, one new-typed thermal protection systems (TPS)-ARMOR TPS is coming forth. ARMOR TPS is means adaptable, robust, metallic, operable, reusable TPS. The ARMOR TPS has many advantages, for example: fixing easily, longer life, good properties, short time of maintenance and service. The ARMOR TPS is one of important candidate structure of RLV. ARMOR thermal protection system in foreign countries for reusable launch vehicle is used instead of the traditional ceramic-matrix composite thermal protection system and C/C thermal protection system. Also the constituent feature of ARMOR thermal protection system is much better than the traditional TPS. In comparison with traditional TPS, the ARMOR TPS will be the best selection for all kinds of RLV. So the ARMOR thermal protection system will be used in aviation and spaceflight field more and more widely because of its much better performance. ARMOR TPS panel is above the whole ARMOR TPS, and the metal honeycomb sandwich structure is the surface of the ARMOR TPS panel. So the metal honeycomb sandwich structure plays an important role in the ARMOR TPS, while it bears the flight dynamic pressure and stands against the flight dynamic calefaction. The metal honeycomb sandwich structure is made using the technique of the whole braze welding. In the course of the vacuum high temperature braze welding, its surface will appear concave. The reasons which lead to the shortage are summarized and discussed. The difference of thermal expansion coefficient and pressure between the core and the panels may be the chief reasons. This paper will analyze the mechanics behavior of metal honeycomb sandwich structure in the course of the vacuum high temperature braze welding, then make sure the reasons and get a way to solve it. Haynes214 is a good material of face sheet at present. γ - TiAl and microlaminate materials are the candidate materials in the future.
Lunar soil and surface processes studies
NASA Technical Reports Server (NTRS)
Glass, B. P.
1975-01-01
Glass particles in lunar soil were characterized and compared to terrestrial analogues. In addition, useful information was obtained concerning the nature of lunar surface processes (e.g. volcanism and impact), maturity of soils and chemistry and heterogeneity of lunar surface material. It is felt, however, that the most important result of the study was that it demonstrated that the investigation of glass particles from the regolith of planetary bodies with little or no atmospheres can be a powerful method for learning about the surface processes and chemistry of planetary surfaces. Thus, the return of samples from other planetary bodies (especially the terrestrial planets and asteroids) using unmanned spacecraft is urged.
NASA Technical Reports Server (NTRS)
2004-01-01
KENNEDY SPACE CENTER, FLA. -- Workers attach a crane to one of the Rudder Speed Brake Actuators that are being removed from the orbiter Atlantis for shipment to the vendor for inspection. An actuator is a motor that moves the tail rudder back and forth to help steer it during landing and brake its speed. The vertical tail consists of a structural fin surface made of aluminum, the Rudder Speed Brake surface, a tip and a lower trailing edge. The rudder splits into two halves to serve as a speed brake. The vertical tail and Rudder Speed Brake are covered with a reusable thermal protection system. Atlantis is undergoing maintenance and inspection in the Orbiter Processing Facility for a future mission.
NASA Technical Reports Server (NTRS)
2004-01-01
KENNEDY SPACE CENTER, FLA. -- Workers attach a crane to one of the Rudder Speed Brake Actuators that are being removed from the orbiter Atlantis for shipment to the vendor for inspection. An actuator is a motor that moves the tail rudder back and forth to help steer it during landing and brake its speed. The vertical tail consists of a structural fin surface made of aluminum, the Rudder Speed Brake surface, a tip and a lower trailing edge. The rudder splits into two halves to serve as a speed brake. The vertical tail and Rudder Speed Brake are covered with a reusable thermal protection system. Atlantis is undergoing maintenance and inspection in the Orbiter Processing Facility for a future mission.
NASA Technical Reports Server (NTRS)
2004-01-01
KENNEDY SPACE CENTER, FLA. -- Workers ensure the safe removal of a Rudder Speed Brake Actuator from the orbiter Atlantis. This and three other actuators are being shipped to the vendor for inspection. An actuator is a motor that moves the tail rudder back and forth to help steer it during landing and brake its speed. The vertical tail consists of a structural fin surface made of aluminum, the Rudder Speed Brake surface, a tip and a lower trailing edge. The rudder splits into two halves to serve as a speed brake. The vertical tail and Rudder Speed Brake are covered with a reusable thermal protection system. Atlantis is undergoing maintenance and inspection in the Orbiter Processing Facility for a future mission.
Atomization characteristics of swirl injector sprays
NASA Technical Reports Server (NTRS)
Feikema, Douglas A.
1996-01-01
Stable combustion within rocket engines is a continuing concern for designers of rocket engine systems. The swirl-coaxial injector has demonstrated effectiveness in achieving atomization and mixing, and therefore stable combustion. Swirl-coaxial injector technology is being deployed in the American RL1OA rocket design and Russian engine systems already make wide spread use of this technology. The present requirement for swirl injector research is derived from NASA's current Reusable Launch Vehicle (RLV) technology program. This report describes some of the background and literature on this topic including drop size measurements, comparison with theoretical predictions, the effect of surface tension on the atomization process, and surface wave characteristics of liquid film at the exit of the injector.
NASA Technical Reports Server (NTRS)
2004-01-01
KENNEDY SPACE CENTER, FLA. -- This is a closeup of one of the Rudder Speed Brake Actuators that are being removed from the orbiter Atlantis for shipment to the vendor for inspection. An actuator is a motor that moves the tail rudder back and forth to help steer it during landing and brake its speed. The vertical tail consists of a structural fin surface made of aluminum, the Rudder Speed Brake surface, a tip and a lower trailing edge. The rudder splits into two halves to serve as a speed brake. The vertical tail and Rudder Speed Brake are covered with a reusable thermal protection system. Atlantis is undergoing maintenance and inspection in the Orbiter Processing Facility for a future mission.
Mechanistic model for catalytic recombination during aerobraking maneuvers
NASA Technical Reports Server (NTRS)
Willey, Ronald J.
1989-01-01
Several mechanistic models are developed to predict recombination coefficients for use in heat shield design for reusable surface insulation (RSI) on aerobraking vehicles such as space shuttles. The models are applied over a temperature range of 300 to 1800 K and a stagnation pressure range of 0 to 3,000 Pa. A four parameter model in temperature was found to work best; however, several models (including those with atom concentrations at the surface) were also investigated. Mechanistic models developed with atom concentration terms may be applicable when sufficient data becomes available. The requirement is shown for recombination experiments in the 300 to 1000 K and 1500 to 1850 K temperature range, with deliberate concentration variations.
Heat resistant protective hand covering
NASA Technical Reports Server (NTRS)
Tschirch, R. P.; Sidman, K. R.; Arons, I. J. (Inventor)
1984-01-01
A heat-resistant aromatic polyamide fiber is described. The outer surface of the shell is coated with a fire-resistant elastomer and liner. Generally conforming and secured to the shell and disposed inwardly of the shell, the liner is made of a felt fabric of temperature-resistant aromatic polymide fiber.
Future Launch Vehicle Structures - Expendable and Reusable Elements
NASA Astrophysics Data System (ADS)
Obersteiner, M. H.; Borriello, G.
2002-01-01
Further evolution of existing expendable launch vehicles will be an obvious element influencing the future of space transportation. Besides this reusability might be the change with highest potential for essential improvement. The expected cost reduction and finally contributing to this, the improvement of reliability including safe mission abort capability are driving this idea. Although there are ideas of semi-reusable launch vehicles, typically two stages vehicles - reusable first stage or booster(s) and expendable second or upper stage - it should be kept in mind that the benefit of reusability will only overwhelm if there is a big enough share influencing the cost calculation. Today there is the understanding that additional technology preparation and verification will be necessary to master reusability and get enough benefits compared with existing launch vehicles. This understanding is based on several technology and system concepts preparation and verification programmes mainly done in the US but partially also in Europe and Japan. The major areas of necessary further activities are: - System concepts including business plan considerations - Sub-system or component technologies refinement - System design and operation know-how and capabilities - Verification and demonstration oriented towards future mission mastering: One of the most important aspects for the creation of those coming programmes and activities will be the iterative process of requirements definition derived from concepts analyses including economical considerations and the results achieved and verified within technology and verification programmes. It is the intention of this paper to provide major trends for those requirements focused on future launch vehicles structures. This will include the aspects of requirements only valid for reusable launch vehicles and those common for expendable, semi-reusable and reusable launch vehicles. Structures and materials is and will be one of the important technology areas to be improved. This includes: - Primary structures - Thermal protection systems (for high and low temperatures) - Hot structures (leading edges, engine cowling, ...) - Tanks (for various propellants and fluids, cryo, ...) Requirements to be considered are including materials properties and a variety of loads definition - static and dynamic. Based on existing knowledge and experience for expendable LV (Ariane, ...) and aircraft there is the need to established a combined understanding to provide the basis for an efficient RLV design. Health monitoring will support the cost efficient operation of future reusable structures, but will also need a sound understanding of loads and failure mechanisms as basis. Risk mitigation will ask for several steps of demonstration towards a cost efficient RLV (structures) operation. Typically this has or will start with basic technology, to be evolved to components demonstration (TPS, tanks, ...) and finally to result in the demonstration of the cost efficient reuse operation. This paper will also include a programmatic logic concerning future LV structures demonstration.
1998-08-10
In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, cuts a High-Temperature Reusable Surface Insulation (HRSI) tile on a gun stock contour milling machine. About 70 percent of a Space Shuttle orbiter’s external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. HRSI tiles cover the lower surface of the orbiter, areas around the forward windows, upper body flap, the base heat shield, the "eyeballs" on the front of the Orbital Maneuvering System (OMS) pods, and the leading and trailing edges of the vertical stabilizer and the rudder speed brake. They are generally 6 inches square, but may also be as large as 12 inches square in some areas, and 1 to 5 inches thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter
Laser writing of single-crystalline gold substrates for surface enhanced Raman spectroscopy
NASA Astrophysics Data System (ADS)
Singh, Astha; Sharma, Geeta; Ranjan, Neeraj; Mittholiya, Kshitij; Bhatnagar, Anuj; Singh, B. P.; Mathur, Deepak; Vasa, Parinda
2017-07-01
Surface enhanced Raman scattering (SERS) spectroscopy, a powerful contemporary tool for studying low-concentration analytes via surface plasmon induced enhancement of local electric field, is of utility in biochemistry, material science, threat detection, and environmental studies. We have developed a simple, fast, scalable, and relatively low-cost optical method of fabricating and characterizing large-area, reusable and broadband SERS substrates with long storage lifetime. We use tightly focused, intense infra-red laser pulses to write gratings on single-crystalline, Au (1 1 1) gold films on mica which act as SERS substrates. Our single-crystalline SERS substrates compare favourably, in terms of surface quality and roughness, to those fabricated in poly-crystalline Au films. Tests show that our SERS substrates have the potential of detecting urea and 1,10-phenantroline adulterants in milk and water, respectively, at 0.01 ppm (or lower) concentrations.
Tony Rollins prepares a new tile for the Space Shuttle orbiter
NASA Technical Reports Server (NTRS)
1998-01-01
In the Tile Fabrication Shop, Tony Rollins, with United Space Alliance, cuts a High-Temperature Reusable Surface Insulation (HRSI) tile on a gun stock contour milling machine. About 70 percent of a Space Shuttle orbiter's external surface is shielded from heat by a network of more than 24,000 tiles formed from a silica fiber compound. HRSI tiles cover the lower surface of the orbiter, areas around the forward windows, upper body flap, the base heat shield, the 'eyeballs' on the front of the Orbital Maneuvering System (OMS) pods, and the leading and trailing edges of the vertical stabilizer and the rudder speed brake. They are generally 6 inches square, but may also be as large as 12 inches square in some areas, and 1 to 5 inches thick. More advanced materials such as Flexible Insulation Blankets have replaced tiles on some upper surfaces of the orbiter.
1996-11-01
Orbit ( SSTO ) Reusable Launch Vehicles (RLVs) are currently under cooperative development by NASA, the Air Force, and the aerospace industry in the pursuit...exploit these rapid transit technologies to advance ’Global Reach for America.’ The SSTO RLV is a single stage rocket that will be completely reusable...investigated to assess the projected capabilities and costs of the SSTO system. This paper reviews the proposed capabilities of the SSTO system, discusses
A reusable rocket engine intelligen control
NASA Technical Reports Server (NTRS)
Merrill, Walter C.; Lorenzo, Carl F.
1988-01-01
An intelligent control system for reusable space propulsion systems for future launch vehicles is described. The system description includes a framework for the design. The framework consists of an execution level with high-speed control and diagnostics, and a coordination level which marries expert system concepts with traditional control. A comparison is made between air breathing and rocket engine control concepts to assess the relative levels of development and to determine the applicability of air breathing control concepts to future reusable rocket engine systems.
A reusable rocket engine intelligent control
NASA Technical Reports Server (NTRS)
Merrill, Walter C.; Lorenzo, Carl F.
1988-01-01
An intelligent control system for reusable space propulsion systems for future launch vehicles is described. The system description includes a framework for the design. The framework consists of an execution level with high-speed control and diagnostics, and a coordination level which marries expert system concepts with traditional control. A comparison is made between air breathing and rocket engine control concepts to assess the relative levels of development and to determine the applicability of air breathing control concepts ot future reusable rocket engine systems.
Huang, Shufeng; Wan, Zhenping; Zou, Shuiping
2018-01-01
A novel sintered cutting stainless steel fiber felt with internal channels (SCSSFFC) composed of a stainless-steel fiber skeleton, three-dimensional interconnected porous structure and multiple circular microchannels is developed. SCSSFFC has a jagged and rough surface morphology and possesses a high specific surface area, which is approximately 2.4 times larger than that of the sintered bundle-drawing stainless steel fiber felt with internal channels (SBDSSFFC) and is expected to enhance adhesive strength. The sol-gel and wet impregnation methods are adopted to prepare SCSSFFC with an Al2O3 coating (SCSSFFC/Al2O3). The adhesive strength of SCSSFFC/Al2O3 is investigated using ultrasonic vibration and thermal shock tests. The experimental results indicate that the weight loss rate of the Al2O3 coating has a 4.2% and 8.42% reduction compared with those of SBDSSFFCs based on ultrasonic vibration and thermal shock tests. In addition, the permeability of SCSSFFC/Al2O3 is investigated based on forced liquid flow tests. The experimental results show that the permeability and inertial coefficients of SCSSFFC/Al2O3 are mainly affected by the coating rate, porosity and open ratio; however, the internal microchannel diameter has little influence. It is also found that SCSSFFC/Al2O3 yields superior permeability, as well as inertial coefficients compared with those of other porous materials reported in the literature. PMID:29558438
Code of Federal Regulations, 2013 CFR
2013-01-01
... for the launch or reentry of a reusable suborbital rocket. Permitted activity means the launch or reentry of a reusable suborbital rocket conducted under a permit issued by the FAA. Property damage means...
Code of Federal Regulations, 2012 CFR
2012-01-01
... for the launch or reentry of a reusable suborbital rocket. Permitted activity means the launch or reentry of a reusable suborbital rocket conducted under a permit issued by the FAA. Property damage means...
Code of Federal Regulations, 2014 CFR
2014-01-01
... for the launch or reentry of a reusable suborbital rocket. Permitted activity means the launch or reentry of a reusable suborbital rocket conducted under a permit issued by the FAA. Property damage means...
14 CFR 437.7 - Scope of an experimental permit.
Code of Federal Regulations, 2014 CFR
2014-01-01
... experimental permit. An experimental permit authorizes launch or reentry of a reusable suborbital rocket. The... return the reusable suborbital rocket to a safe condition after it lands or impacts. ...
14 CFR 437.7 - Scope of an experimental permit.
Code of Federal Regulations, 2013 CFR
2013-01-01
... experimental permit. An experimental permit authorizes launch or reentry of a reusable suborbital rocket. The... return the reusable suborbital rocket to a safe condition after it lands or impacts. ...
14 CFR 437.7 - Scope of an experimental permit.
Code of Federal Regulations, 2012 CFR
2012-01-01
... experimental permit. An experimental permit authorizes launch or reentry of a reusable suborbital rocket. The... return the reusable suborbital rocket to a safe condition after it lands or impacts. ...
14 CFR 437.7 - Scope of an experimental permit.
Code of Federal Regulations, 2010 CFR
2010-01-01
... experimental permit. An experimental permit authorizes launch or reentry of a reusable suborbital rocket. The... return the reusable suborbital rocket to a safe condition after it lands or impacts. ...
14 CFR 437.7 - Scope of an experimental permit.
Code of Federal Regulations, 2011 CFR
2011-01-01
... experimental permit. An experimental permit authorizes launch or reentry of a reusable suborbital rocket. The... return the reusable suborbital rocket to a safe condition after it lands or impacts. ...
Metadata-driven Delphi rating on the Internet.
Deshpande, Aniruddha M; Shiffman, Richard N; Nadkarni, Prakash M
2005-01-01
Paper-based data collection and analysis for consensus development is inefficient and error-prone. Computerized techniques that could improve efficiency, however, have been criticized as costly, inconvenient and difficult to use. We designed and implemented a metadata-driven Web-based Delphi rating and analysis tool, employing the flexible entity-attribute-value schema to create generic, reusable software. The software can be applied to various domains by altering the metadata; the programming code remains intact. This approach greatly reduces the marginal cost of re-using the software. We implemented our software to prepare for the Conference on Guidelines Standardization. Twenty-three invited experts completed the first round of the Delphi rating on the Web. For each participant, the software generated individualized reports that described the median rating and the disagreement index (calculated from the Interpercentile Range Adjusted for Symmetry) as defined by the RAND/UCLA Appropriateness Method. We evaluated the software with a satisfaction survey using a five-level Likert scale. The panelists felt that Web data entry was convenient (median 4, interquartile range [IQR] 4.0-5.0), acceptable (median 4.5, IQR 4.0-5.0) and easily accessible (median 5, IQR 4.0-5.0). We conclude that Web-based Delphi rating for consensus development is a convenient and acceptable alternative to the traditional paper-based method.
The X-20 space plane: Past innovation, future vision
NASA Astrophysics Data System (ADS)
Sunday, Terry L.; London, John R.
In November 1957, the U.S. Air Force initiated an aerospace project that was one of the most innovative concepts of its day, and also provided an accurate glimpse into the future. The X-20 space plane, known as Dyna-Soar, never reached operational status—it was cancelled in December 1963, before the first prototype was built. But even though the diminutive vehicle never flew, technological advances made during its development laid the foundation for many later manned space systems, including some as new as tomorrow's headlines. The paper examines both the history and the technology of Dyna-Soar. The space plane's unique design and its proposed missions are examined, along with the ever-changing political, economic and programmatic environments that led to its conception, its long, painful gestation period, and its demise. The X-20 premiered many innovations to solve the challenges of launch, manned orbital operations and re-entry for a re-usable spacecraft. Many of these technologies did not reach fruition until decades later. Based largely on recently declassified material, this paper places Dyna-Soar into a broad historical context as an interesting research vehicle concept from three decades past, and as the purveyor of a technological legacy whose impacts are still being felt today.
Historical problem areas: Lessons learned for expendable and reusable vehicle propulsion systems
NASA Technical Reports Server (NTRS)
Fester, Dale A.
1991-01-01
The following subject areas are covered: expendable launch vehicle lessons learned, upper stage/transfer vehicle lessons learned, shuttle systems - reuse, and reusable system issues and lessons learned.
Liu, Xiaocheng; Yang, Danxing; Zhou, Yaoyu; Zhang, Jiachao; Luo, Lin; Meng, Sijun; Chen, Song; Tan, Mengjiao; Li, Zhicheng; Tang, Lin
2017-09-01
The degradation of antibiotic levofloxacin was investigated by dimensionally stable anode as well as modified cathode using low-cost chemical reagents of hydrazine hydrate and ethanol for electro-Fenton in an undivided cell at pH 3.0 under room temperature. Comparison of unmodified and modified cathode was performed. The apparent rate constant of levofloxacin decay was found to be 0.2883 min -1 for graphite felt-10 with the best performance at 200 mA, which is lower than graphite felt at 400 mA. The optimum modified cathode showed a significant improvement of complete mineralization of levofloxacin, reaching a 92% TOC removal at 200 mA for 480 min higher than unmodified one at twice the current. Surface physicochemical properties and morphology were investigated by scanning electron microscope, contact angle and X-ray photoelectron spectroscopy. The electrochemical characterization of hydrogen evolution reaction was adopted to clarify a possible pathway for the higher mineralization of levofloxacin, indicating a potential pilot-scale study to the pollution with the similar structure. Copyright © 2017 Elsevier Ltd. All rights reserved.
Chemical composition of felt-tip pen inks.
Germinario, Giulia; Garrappa, Silvia; D'Ambrosio, Valeria; van der Werf, Inez Dorothé; Sabbatini, Luigia
2018-01-01
Felt-tip pens are frequently used for the realization of sketches, drawings, architectural projects, and other technical designs. The formulations of these inks are usually rather complex and may be associated to those of modern paint materials where, next to the binding medium and pigments/dyes, solvents, fillers, emulsifiers, antioxidants, plasticizers, light stabilizers, biocides, and so on are commonly added. Felt-tip pen inks are extremely sensitive to degradation and especially exposure to light may cause chromatic changes and fading. In this study, we report on the complete chemical characterization of modern felt-tip pen inks that are commercially available and commonly used for the realization of artworks. Three brands of felt-tip pens (Faber-Castell, Edding, and Stabilo) were investigated with complementary analytical techniques such as thin-layer chromatography (TLC), VIS-reflectance spectroscopy, μ-Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS), pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), GC-MS, and Fourier transform infrared (FTIR) spectroscopy. The use of TLC proved to be very powerful in the study of complex mixtures of synthetic dyes. First derivatives of the reflectance spectra acquired on the TLC spots were useful in the preliminary identification of the dye, followed by Raman spectroscopy and SERS, which allowed for the unambiguous determination of the chemical composition of the pigments (phthalocyanines, dioxazines, and azo pigments) and dyes (azo dyes, triarylmethanes, xanthenes). FTIR spectroscopy was used especially for the detection of additives, as well as for confirming the nature of solvents and dyes/pigments. Finally, (Py-)GC-MS data provided information on the binders (styrene-acrylic resins, plant gums), solvents, and additives, as well as on pigments and dyes.
Reusable and disposable cups: An energy-based evaluation
NASA Astrophysics Data System (ADS)
Hocking, Martin B.
1994-11-01
A group of five different types of reusable and disposable hot drink cups have been analyzed in detail with respect to their overall energy costs during fabrication and use. Electricity generating methods and efficiencies have been found to be key factors in the primary energy consumption for the washing of reusable cups and a less important factor in cup fabrication. In Canada or the United States, over 500 or more use cycles, reusable cups are found to have about the same or slightly more energy consumption, use for use, as moulded polystyrene foam cups used once and then discarded. For the same area paper cups used once and discarded are found to consume less fossil fuel energy per use than any of the other cup types examined. Details of this analysis, which could facilitate the comparative assessment of other scenarios, are presented.
RL-10 Based Combined Cycle For A Small Reusable Single-Stage-To-Orbit Launcher
NASA Technical Reports Server (NTRS)
Balepin, Vladimir; Price, John; Filipenco, Victor
1999-01-01
This paper discusses a new application of the combined propulsion known as the KLIN(TM) cycle, consisting of a thermally integrated deeply cooled turbojet (DCTJ) and liquid rocket engine (LRE). If based on the RL10 rocket engine family, the KLIN (TM) cycle makes a small single-stage-to-orbit (SSTO) reusable launcher feasible and economically very attractive. Considered in this paper are the concept and parameters of a small SSTO reusable launch vehicle (RLV) powered by the KLIN (TM) cycle (sSSTO(TM)) launcher. Also discussed are the benefits of the small launcher, the reusability, and the combined cycle application. This paper shows the significant reduction of the gross take off weight (GTOW) and dry weight of the KLIN(TM) cycle-powered launcher compared to an all-rocket launcher.
Microservices in Web Objects Enabled IoT Environment for Enhancing Reusability
Chong, Ilyoung
2018-01-01
In the ubiquitous Internet of Things (IoT) environment, reusing objects instead of creating new one has become important in academics and industries. The situation becomes complex due to the availability of a huge number of connected IoT objects, and each individual service creates a new object instead of reusing the existing one to fulfill a requirement. A well-standard mechanism not only improves the reusability of objects but also improves service modularity and extensibility, and reduces cost. Web Objects enabled IoT environment applies the principle of reusability of objects in multiple IoT application domains through central objects repository and microservices. To reuse objects with microservices and to maintain a relationship with them, this study presents an architecture of Web of Objects platform. In the case of a similar request for an object, the already instantiated object that exists in the same or from other domain can be reused. Reuse of objects through microservices avoids duplications, and reduces time to search and instantiate them from their registries. Further, this article presents an algorithm for microservices and related objects discovery that considers the reusability of objects through the central objects repository. To support the reusability of objects, the necessary algorithm for objects matching is also presented. To realize the reusability of objects in Web Objects enabled IoT environment, a prototype has been designed and implemented based on a use case scenario. Finally, the results of the prototype have been analyzed and discussed to validate the proposed approach. PMID:29373491
Microservices in Web Objects Enabled IoT Environment for Enhancing Reusability.
Jarwar, Muhammad Aslam; Kibria, Muhammad Golam; Ali, Sajjad; Chong, Ilyoung
2018-01-26
In the ubiquitous Internet of Things (IoT) environment, reusing objects instead of creating new one has become important in academics and industries. The situation becomes complex due to the availability of a huge number of connected IoT objects, and each individual service creates a new object instead of reusing the existing one to fulfill a requirement. A well-standard mechanism not only improves the reusability of objects but also improves service modularity and extensibility, and reduces cost. Web Objects enabled IoT environment applies the principle of reusability of objects in multiple IoT application domains through central objects repository and microservices. To reuse objects with microservices and to maintain a relationship with them, this study presents an architecture of Web of Objects platform. In the case of a similar request for an object, the already instantiated object that exists in the same or from other domain can be reused. Reuse of objects through microservices avoids duplications, and reduces time to search and instantiate them from their registries. Further, this article presents an algorithm for microservices and related objects discovery that considers the reusability of objects through the central objects repository. To support the reusability of objects, the necessary algorithm for objects matching is also presented. To realize the reusability of objects in Web Objects enabled IoT environment, a prototype has been designed and implemented based on a use case scenario. Finally, the results of the prototype have been analyzed and discussed to validate the proposed approach.
Health Monitoring Technology for Thermal Protection Systems on Reusable Hypersonic Vehicles
NASA Technical Reports Server (NTRS)
Milos, Frank S.; Watters, D. G.; Heinemann, J. M.; Karunaratne, K. S.; Arnold, Jim (Technical Monitor)
2001-01-01
Integrated subsystem health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles (RLVs) in order to reduce life cycle costs, to increase safety margins, and to improve mission reliability. This talk summarizes a joint effort between NASA Ames and industry partners to develop rapid non-contact diagnostic tools for health and performance monitoring of thermal protection systems (TPS) on future RLVs. The specific goals for TPS health monitoring are to increase the speed and reliability of TPS inspections for improved operability at lower cost. The technology being developed includes a 3-D laser scanner for examining the exterior surface of the TPS, and a subsurface microsensor suite for monitoring the health and performance of the TPS. The sensor suite consists of passive overlimit sensors and sensors for continuous parameter monitoring in flight. The sensors are integrated with radio-frequency identification (RFID) microchips to enable wireless communication of-the sensor data to an external reader that may be a hand-held scanner or a large portal. Prototypes of the laser system and both types of subsurface sensors have been developed. The laser scanner was tested on Shuttle Orbiter Columbia and was able to dimension surface chips and holes on a variety of TPS materials. The temperature-overlimit microsensor has a diameter under 0.05 inch (suitable for placement in gaps between ceramic TPS tiles) and can withstand 700 F for 15 minutes.
Bertrand, Brandt; Trejo-Hernández, María R; Morales-Guzmán, Daniel; Caspeta, Luis; Suárez Rodríguez, Ramón; Martínez-Morales, Fernando
2016-12-01
A Trametes versicolor laccase was functionally expressed on the membrane surface of Saccharomyces cerevisiae EBY100. Laccase expression was increased 6.57-fold by medium optimization and surpassed production by the native strain. Maximal laccase and biomass production reached 19 735 ± 1719 Ug -1 and 6.22 ± 0.53 gL -1 respectively, after 2 d of culture. Optimum oxidization of all substrates by laccase was observed at pH 3. Laccase showed high affinity towards substrates used with Km (mM) and Vmax (μmol min -1 ) values of 0.57 ± 0.0047 and 24.55 ± 0.64, 1.52 ± 0.52 and 9.25 ± 1.78, and 2.67 ± 0.12 and 11.26 ± 0.75, were reported for ABTS, 2, 6-DMP and GUA, respectively. EDTA and NaN 3 displayed none competitive inhibition towards laccase activity. The optimum temperature for activity was 50 °C; however, the enzyme was stable over a wide range of temperatures (25-70 °C). The biologically immobilized laccase showed high reusability towards phenolic substrates and low reusability with non-phenolic substrates. High affinity for a diversity phenolic compounds and great ethanol tolerance substantiates this laccase/yeast biocatalyst potential for application in the production of bioethanol. Copyright © 2016 British Mycological Society. Published by Elsevier Ltd. All rights reserved.
Project of Ariane 5 LV family advancement by use of reusable fly-back boosters (named “Bargouzine”)
NASA Astrophysics Data System (ADS)
Sumin, Yu.; Bonnal, Ch.; Kostromin, S.; Panichkin, N.
2007-12-01
The paper concerns possible concept variants of a partially reusable Heavy-Lift Launch Vehicle derived from the advanced basic launcher (Ariane-2010) by means of substitution of the EAP Solid Rocket Boosters for a Reusable Starting Stage consisting two Liquid-propellant Reusable Fly-Back Boosters called "Bargouzin". This paper describes the status of the presently studied RFBB concepts during its three phases. The first project phase was dedicated to feasibility expertise of liquid-rocket reusable fly-back boosters ("Baikal" type) utilization for heavy-lift space launch vehicle. The design features and main conclusions are presented. The second phase has been performed with the purpose of selection of preferable concept among the alternative ones for the future Ariane LV modernization by using RFBB instead of EAP Boosters. The main requirements, logic of work, possible configuration and conclusion are presented. Initial aerodynamic, ballistic, thermoloading, dynamic loading, trade-off and comparison analysis have been performed on these concepts. The third phase consists in performing a more detailed expertise of the chosen LV concept. This part summarizes some of the more detailed results related to flight performance, system mass, thermoprotection system, aspects of technologies, ground complex modification, comparison analyses and conclusion.
Single-stage-to-orbit: Meeting the challenge
NASA Astrophysics Data System (ADS)
Freeman, Delma C., Jr.; Talay, Theodore A.; Austin, Robert Eugene
1995-10-01
There has been and continues to be significant discussion about the viability of fully reusable, single-stage-to-orbit (SSTO) concepts for delivery of payloads to orbit. Often, these discussions have focused in detail on performance and technology requirements relating to the technical feasibility of the concept, with only broad generalizations on how the SSTO will achieve its economic goals of greatly reduced vehicle ground and flight operations costs. With the current industry and NASA Reusable Launch Vehicle Technology Program efforts underway to mature and demonstrate technologies leading to a viable commercial launch system that also satisfies national needs, achieving acceptable recurring costs becomes a significant challenge. This paper reviews the current status of the Reusable Launch Vehicle Technology Program including the DC-XA, X-33, and X-34 flight systems and associated technology programs. The paper also examines lessons learned from the recently completed DC-X reusable rocket demonstrator program. It examines how these technologies and flight systems address the technical and operability challenges of SSTO whose solutions are necessary to reduce costs. The paper also discusses the management and operational approaches that address the challenge of a new cost-effective, reusable launch vehicle system.
Single-stage-to-orbit — Meeting the challenge
NASA Astrophysics Data System (ADS)
Freeman, Delma C.; Talay, Theodore A.; Austin, Robert Eugene
1996-02-01
There has been and continues to be significant discussion about the viability of fully reusable, single-stage-to-orbit (SSTO) concepts for delivery of payloads to orbit. Often, these discussions have focused in detail on performance and technology requirements relating to the technical feasibility of the concept, with only broad generalizations on how the SSTO will achieve its economic goals of greatly reduced vehicle ground and flight operations costs. With the current industry and NASA Reusable Launch Vehicle Technology Program efforts underway to mature and demonstrate technologies leading to a viable commercial launch system that also satisfies national needs, achieving acceptable recurring costs becomes a significant challenge. This paper reviews the current status of the Reusable Launch Vehicle Technology Program including the DC-XA, X-33, X-34 flight systems and associated technology programs. The paper also examines lessons learned from the recently completed DC-X reusable rocket demonstrator program. It examines how these technologies and flight systems address the technical and operability challenges of SSTO whose solutions are necessary to reduce costs. The paper also discusses the management and operational approaches that address the challenge of a new cost-effective, reusable launch vehicle system.
A literature review on business process modelling: new frontiers of reusability
NASA Astrophysics Data System (ADS)
Aldin, Laden; de Cesare, Sergio
2011-08-01
Business process modelling (BPM) has become fundamental for modern enterprises due to the increasing rate of organisational change. As a consequence, business processes need to be continuously (re-)designed as well as subsequently aligned with the corresponding enterprise information systems. One major problem associated with the design of business processes is reusability. Reuse of business process models has the potential of increasing the efficiency and effectiveness of BPM. This article critically surveys the existing literature on the problem of BPM reusability and more specifically on that State-of-the-Art research that can provide or suggest the 'elements' required for the development of a methodology aimed at discovering reusable conceptual artefacts in the form of patterns. The article initially clarifies the definitions of business process and business process model; then, it sets out to explore the previous research conducted in areas that have an impact on reusability in BPM. The article concludes by distilling directions for future research towards the development of apatterns-based approach to BPM; an approach that brings together the contributions made by the research community in the areas of process mining and discovery, declarative approaches and ontologies.
Incrementally developing a cultural and regulatory infrastructure for reusable launch vehicles
NASA Astrophysics Data System (ADS)
Simberg, Rand
1998-01-01
At this point in time, technology is perhaps the least significant barrier to the development of high-flight-rate, reusable launchers, necessary for low-cost space access. Much more daunting are the issues of regulatory regimes, needed markets, and public/investor perception of their feasibility. The approach currently the focus of the government (X-33) assumes that the necessary conditions will be in place to support a new reusable launch vehicle in the Shuttle class at the end of the X-33 development. For a number of reasons (market size, lack of confidence in the technology, regulations designed for expendable vehicles, difficulties in capital formation) such an approach may prove too rapid a leap for success. More incremental steps, both experimental and operational, could be a higher-probability path to achieving the goal of cheap access through reusables. Such incrementalism, via intermediate vehicles (possibly multi-stage) exploiting suborbital and smaller-payload markets, could provide the gradual acclimatization of the public, regulatory and investment communities to reusable launchers, and build the confidence necessary to go on to subsequent steps to provide truly cheap access, while providing lower-cost access much sooner.
Automated reuseable components system study results
NASA Technical Reports Server (NTRS)
Gilroy, Kathy
1989-01-01
The Automated Reusable Components System (ARCS) was developed under a Phase 1 Small Business Innovative Research (SBIR) contract for the U.S. Army CECOM. The objectives of the ARCS program were: (1) to investigate issues associated with automated reuse of software components, identify alternative approaches, and select promising technologies, and (2) to develop tools that support component classification and retrieval. The approach followed was to research emerging techniques and experimental applications associated with reusable software libraries, to investigate the more mature information retrieval technologies for applicability, and to investigate the applicability of specialized technologies to improve the effectiveness of a reusable component library. Various classification schemes and retrieval techniques were identified and evaluated for potential application in an automated library system for reusable components. Strategies for library organization and management, component submittal and storage, and component search and retrieval were developed. A prototype ARCS was built to demonstrate the feasibility of automating the reuse process. The prototype was created using a subset of the classification and retrieval techniques that were investigated. The demonstration system was exercised and evaluated using reusable Ada components selected from the public domain. A requirements specification for a production-quality ARCS was also developed.
Surface Analysis Evaluation of Handwipe Cleaning for the Space Shuttle RSRM
NASA Technical Reports Server (NTRS)
Lesley, Michael W.; Anderson, Erin L.; McCool, Alex (Technical Monitor)
2001-01-01
In this paper we discuss the role of surface-sensitive spectroscopy (electron spectroscopy for chemical analysis, or ESCA) in the selection of solvents to replace 1,1,1-trichloroethane in handwipe cleaning of bonding surfaces on NASA's Space Shuttle Reusable Solid Rocket Motor (RSRM). Removal of common process soils from a wide variety of metallic and polymeric substrates was characterized. The cleaning efficiency was usually more dependent on the type of substrate being cleaned and the specific process soil than on the solvent used. A few substrates that are microscopically rough or porous proved to be difficult to clean with any cleaner, and some soils were very tenacious and difficult to remove from any substrate below detection limits. Overall, the work showed that a wide variety of solvents will perform at least as well as 1,1,1-trichloroethane.
Zhang, Yanyan; Gao, Baojiao; An, Fuqiang; Xu, Zeqing; Zhang, Tingting
2014-09-12
In this paper, on the basis of surface-initiated graft polymerization, a new surface molecular imprinting technique is established by molecular design. And molecularly imprinted polymer MIP-PMAA/SiO2 is successfully prepared with genistein as template. The adsorption and recognition characteristics of MIP-PMAA/SiO2 for genistein are studied in depth by using static method, dynamic method and competitive adsorption experiment. The experimental results show that MIP-PMAA/SiO2 possesses very strong adsorption affinity and specific recognition for genistein. The saturated adsorption capacity could reach to 0.36mmolg(-1). The selectivity coefficients relative to quercetin and rutin are 5.4 and 11.8, respectively. Besides, MIP-PMAA/SiO2 is regenerated easily and exhibits excellent reusability. Copyright © 2014 Elsevier B.V. All rights reserved.
Mitigation of EMU Glove Cut Hazard by MMOD Impact Craters on Exposed ISS Handrails
NASA Technical Reports Server (NTRS)
Christiansen, Eric L.; Ryan, Shannon
2009-01-01
Recent cut damages to crewmember extravehicular mobility unit (EMU) gloves during extravehicular activity (EVA) onboard the International Space Station (ISS) has been found to result from contact with sharp edges or pinch points rather than general wear or abrasion. One possible source of cut-hazards are protruding sharp edged crater lips from impact of micrometeoroid and orbital debris (MMOD) particles on external metallic handrails along EVA translation paths. During impact of MMOD particles at hypervelocity an evacuation flow develops behind the shock wave, resulting in the formation of crater lips that can protrude above the target surface. In this study, two methods were evaluated to limit EMU glove cut-hazards due to MMOD impact craters. In the first phase, four flexible overwrap configurations are evaluated: a felt-reusable surface insulation (FRSI), polyurethane polyether foam with beta-cloth cover, double-layer polyurethane polyether foam with beta-cloth cover, and multi-layer beta-cloth with intermediate Dacron netting spacers. These overwraps are suitable for retrofitting ground equipment that has yet to be flown, and are not intended to protect the handrail from impact of MMOD particles, rather to act as a spacer between hazardous impact profiles and crewmember gloves. At the impact conditions considered, all four overwrap configurations evaluated were effective in limiting contact between EMU gloves and impact crater profiles. The multi-layer beta-cloth configuration was the most effective in reducing the height of potentially hazardous profiles in handrail-representative targets. In the second phase of the study, four material alternatives to current aluminum and stainless steel alloys were evaluated: a metal matrix composite, carbon fiber reinforced plastic (CFRP), fiberglass, and a fiber metal laminate. Alternative material handrails are intended to prevent the formation of hazardous damage profiles during MMOD impact and are suitable for flight hardware yet to be constructed. Of the four materials evaluated, only the fiberglass formed a less hazardous damage profile than the baseline metallic target. Although the CFRP laminate did not form any noticeable crater lip, brittle protruding fibers are considered a puncture risk. In parallel with EMU glove redesign efforts, modifications to metallic ISS handrails such as those evaluated in this study provide the means to significantly reduce cut-hazards from MMOD impact craters.
NASA Technical Reports Server (NTRS)
Curran, R. T.
1971-01-01
A flight computer functional executive design for the reusable shuttle is presented. The design is given in the form of functional flowcharts and prose description. Techniques utilized in the regulation of process flow to accomplish activation, resource allocation, suspension, termination, and error masking based on process primitives are considered. Preliminary estimates of main storage utilization by the Executive are furnished. Conclusions and recommendations for timely, effective software-hardware integration in the reusable shuttle avionics system are proposed.
Reusable Agena study. Volume 2: Technical
NASA Technical Reports Server (NTRS)
Carter, W. K.; Piper, J. E.; Douglass, D. A.; Waller, E. W.; Hopkins, C. V.; Fitzgerald, E. T.; Sagawa, S. S.; Carter, S. A.; Jensen, H. L.
1974-01-01
The application of the existing Agena vehicle as a reusable upper stage for the space shuttle is discussed. The primary objective of the study is to define those changes to the Agena required for it to function in the reusable mode in the 100 percent capture of the NASA-DOD mission model. This 100 percent capture is achieved without use of kick motors or stages by simply increasing the Agena propellant load by using optional strap-on-tanks. The required shuttle support equipment, launch and flight operations techniques, development program, and cost package are also defined.
G STL: the geostatistical template library in C++
NASA Astrophysics Data System (ADS)
Remy, Nicolas; Shtuka, Arben; Levy, Bruno; Caers, Jef
2002-10-01
The development of geostatistics has been mostly accomplished by application-oriented engineers in the past 20 years. The focus on concrete applications gave birth to many algorithms and computer programs designed to address different issues, such as estimating or simulating a variable while possibly accounting for secondary information such as seismic data, or integrating geological and geometrical data. At the core of any geostatistical data integration methodology is a well-designed algorithm. Yet, despite their obvious differences, all these algorithms share many commonalities on which to build a geostatistics programming library, lest the resulting library is poorly reusable and difficult to expand. Building on this observation, we design a comprehensive, yet flexible and easily reusable library of geostatistics algorithms in C++. The recent advent of the generic programming paradigm allows us elegantly to express the commonalities of the geostatistical algorithms into computer code. Generic programming, also referred to as "programming with concepts", provides a high level of abstraction without loss of efficiency. This last point is a major gain over object-oriented programming which often trades efficiency for abstraction. It is not enough for a numerical library to be reusable, it also has to be fast. Because generic programming is "programming with concepts", the essential step in the library design is the careful identification and thorough definition of these concepts shared by most geostatistical algorithms. Building on these definitions, a generic and expandable code can be developed. To show the advantages of such a generic library, we use G STL to build two sequential simulation programs working on two different types of grids—a surface with faults and an unstructured grid—without requiring any change to the G STL code.
Reusable single-port access device shortens operative time and reduces operative costs.
Shussman, Noam; Kedar, Asaf; Elazary, Ram; Abu Gazala, Mahmoud; Rivkind, Avraham I; Mintz, Yoav
2014-06-01
In recent years, single-port laparoscopy (SPL) has become an attractive approach for performing surgical procedures. The pitfalls of this approach are technical and financial. Financial concerns are due to the increased cost of dedicated devices and prolonged operating room time. Our aim was to calculate the cost of SPL using a reusable port and instruments in order to evaluate the cost difference between this approach to SPL using the available disposable ports and standard laparoscopy. We performed 22 laparoscopic procedures via the SPL approach using a reusable single-port access system and reusable laparoscopic instruments. These included 17 cholecystectomies and five other procedures. Operative time, postoperative length of stay (LOS) and complications were prospectively recorded and were compared with similar data from our SPL database. Student's t test was used for statistical analysis. SPL was successfully performed in all cases. Mean operative time for cholecystectomy was 72 min (range 40-116). Postoperative LOS was not changed from our standard protocols and was 1.1 days for cholecystectomy. The postoperative course was within normal limits for all patients and perioperative morbidity was recorded. Both operative time and length of hospital stay were shorter for the 17 patients who underwent cholecystectomy using a reusable port than for the matched previous 17 SPL cholecystectomies we performed (p < 0.001). Prices of disposable SPL instruments and multiport access devices as well as extraction bags from different manufacturers were used to calculate the cost difference. Operating with a reusable port ended up with an average cost savings of US$388 compared with using disposable ports, and US$240 compared with standard laparoscopy. Single-port laparoscopic surgery is a technically challenging and expensive surgical approach. Financial concerns among others have been advocated against this approach; however, we demonstrate herein that using a reusable port and instruments reduces operative time and overall operative costs, even beyond the cost of standard laparoscopy.
14 CFR 437.53 - Pre-flight and post-flight operations.
Code of Federal Regulations, 2013 CFR
2013-01-01
... operations and systems in preparing a reusable suborbital rocket for flight at a launch site in the United States and returning the reusable suborbital rocket and any support equipment to a safe condition after...
14 CFR 437.53 - Pre-flight and post-flight operations.
Code of Federal Regulations, 2010 CFR
2010-01-01
... operations and systems in preparing a reusable suborbital rocket for flight at a launch site in the United States and returning the reusable suborbital rocket and any support equipment to a safe condition after...
14 CFR 437.53 - Pre-flight and post-flight operations.
Code of Federal Regulations, 2011 CFR
2011-01-01
... operations and systems in preparing a reusable suborbital rocket for flight at a launch site in the United States and returning the reusable suborbital rocket and any support equipment to a safe condition after...
14 CFR 437.53 - Pre-flight and post-flight operations.
Code of Federal Regulations, 2014 CFR
2014-01-01
... operations and systems in preparing a reusable suborbital rocket for flight at a launch site in the United States and returning the reusable suborbital rocket and any support equipment to a safe condition after...
14 CFR 437.53 - Pre-flight and post-flight operations.
Code of Federal Regulations, 2012 CFR
2012-01-01
... operations and systems in preparing a reusable suborbital rocket for flight at a launch site in the United States and returning the reusable suborbital rocket and any support equipment to a safe condition after...
REUSABLE PROPULSION ARCHITECTURE FOR SUSTAINABLE LOW-COST ACCESS TO SPACE
NASA Technical Reports Server (NTRS)
Bonometti, J. A.; Dankanich, J. W.; Frame, K. L.
2005-01-01
The primary obstacle to any space-based mission is, and has always been, the cost of access to space. Even with impressive efforts toward reusability, no system has come close to lowering the cost a significant amount. It is postulated here, that architectural innovation is necessary to make reusability feasible, not incremental subsystem changes. This paper shows two architectural approaches of reusability that merit further study investments. Both #inherently# have performance increases and cost advantages to make affordable access to space a near term reality. A rocket launched from a subsonic aircraft (specifically the Crossbow methodology) and a momentum exchange tether, reboosted by electrodynamics, offer possibilities of substantial reductions in the total transportation architecture mass - making access-to-space cost-effective. They also offer intangible benefits that reduce risk or offer large growth potential. The cost analysis indicates that approximately a 50% savings is obtained using today#s aerospace materials and practices.
Turnaround operations analysis for OTV. Volume 1: Executive summary
NASA Technical Reports Server (NTRS)
1988-01-01
Anaylses performed for ground processing, both expendable and reusable ground-based Orbital Transfer Vehicles (OTVs) launched on the Space Transportation System (STS), a reusable space-based OTV (SBOTV) launched on the STS, and a reusable ground-based OTV (GBOTV) launched on an unmanned cargo vehicle and recovered by the Orbiter are summarized. Also summarized are the analyses performed for space processing the reusable SBOTV at the Space Station in low Earth orbit (LEO) as well as the maintenance and servicing of the SBOTV accommodations at the Space Station. In addition, the candidate OTV concepts, design and interface requirements, and the Space Station design, support, and interface requirements are summarized. A development schedule and associated costs for the required SBOTV accommodations at the Space Station are presented. Finallly, the technology development plan to develop the capability to process both GBOTVs and SBOTVs are summarized.
Risk Perception and Communication in Commercial Reusable Launch Vehicle Operations
NASA Astrophysics Data System (ADS)
Hardy, Terry L.
2005-12-01
A number of inventors and entrepreneurs are currently attempting to develop and commercially operate reusable launch vehicles to carry voluntary participants into space. The operation of these launch vehicles, however, produces safety risks to the crew, to the space flight participants, and to the uninvolved public. Risk communication therefore becomes increasingly important to assure that those involved in the flight understand the risk and that those who are not directly involved understand the personal impact of RLV operations on their lives. Those involved in the launch vehicle flight may perceive risk differently from those non-participants, and these differences in perception must be understood to effectively communicate this risk. This paper summarizes existing research in risk perception and communication and applies that research to commercial reusable launch vehicle operations. Risk communication is discussed in the context of requirements of United States law for informed consent from any space flight participants on reusable suborbital launch vehicles.
Benefits of Government Incentives for Reusable Launch Vehicle Development
NASA Technical Reports Server (NTRS)
Shaw, Eric J.; Hamaker, Joseph W.; Prince, Frank A.
1998-01-01
Many exciting new opportunities in space, both government missions and business ventures, could be realized by a reduction in launch prices. Reusable launch vehicle (RLV) designs have the potential to lower launch costs dramatically from those of today's expendable and partially-expendable vehicles. Unfortunately, governments must budget to support existing launch capability, and so lack the resources necessary to completely fund development of new reusable systems. In addition, the new commercial space markets are too immature and uncertain to motivate the launch industry to undertake a project of this magnitude and risk. Low-cost launch vehicles will not be developed without a mature market to service; however, launch prices must be reduced in order for a commercial launch market to mature. This paper estimates and discusses the various benefits that may be reaped from government incentives for a commercial reusable launch vehicle program.
Enhancing Users' Participation in Business Process Modeling through Ontology-Based Training
NASA Astrophysics Data System (ADS)
Macris, A.; Malamateniou, F.; Vassilacopoulos, G.
Successful business process design requires active participation of users who are familiar with organizational activities and business process modelling concepts. Hence, there is a need to provide users with reusable, flexible, agile and adaptable training material in order to enable them instil their knowledge and expertise in business process design and automation activities. Knowledge reusability is of paramount importance in designing training material on process modelling since it enables users participate actively in process design/redesign activities stimulated by the changing business environment. This paper presents a prototype approach for the design and use of training material that provides significant advantages to both the designer (knowledge - content reusability and semantic web enabling) and the user (semantic search, knowledge navigation and knowledge dissemination). The approach is based on externalizing domain knowledge in the form of ontology-based knowledge networks (i.e. training scenarios serving specific training needs) so that it is made reusable.
Jeong, Seongmin; Cho, Hyunmin; Han, Seonggeun; Won, Phillip; Lee, Habeom; Hong, Sukjoon; Yeo, Junyeob; Kwon, Jinhyeong; Ko, Seung Hwan
2017-07-12
Air quality has become a major public health issue in Asia including China, Korea, and India. Particulate matters are the major concern in air quality. We present the first environmental application demonstration of Ag nanowire percolation network for a novel, electrical type transparent, reusable, and active PM2.5 air filter although the Ag nanowire percolation network has been studied as a very promising transparent conductor in optoelectronics. Compared with previous particulate matter air filter study using relatively weaker short-range intermolecular force in polar polymeric nanofiber, Ag nanowire percolation network filters use stronger long-range electrostatic force to capture PM2.5, and they are highly efficient (>99.99%), transparent, working on an active mode, low power consumption, antibacterial, and reusable after simple washing. The proposed new particulate matter filter can be applied for a highly efficient, reusable, active and energy efficient filter for wearable electronics application.
NASA Astrophysics Data System (ADS)
Goehlich, Robert A.; Rücker, Udo
2005-01-01
It is believed that a potential means for further significant reduction of the recurrent launch cost, which results also in a stimulation of launch rates of small satellites, is to make the launcher reusable, to increase its reliability and to make it suitable for new markets such as mass space tourism. Therefore, not only launching small satellites with expendable rockets on non-regular flights but also with reusable rockets on regular flights should be considered for the long term. However, developing, producing and operating reusable rockets require a fundamental change in the current "business as usual" philosophy. Under current conditions, it might not be possible to develop, to produce or to operate a reusable vehicle fleet economically. The favorite philosophy is based on "smart business" processes adapted by the authors using cost engineering techniques. In the following paper, major strategies for reducing costs are discussed, which are applied for a representative program proposal.
Davis, Niall F; McGrath, Shannon; Quinlan, Mark; Jack, Gregory; Lawrentschuk, Nathan; Bolton, Damien M
2018-03-01
There are no comparative assessments on the environmental impact of endourologic instruments. We evaluated and compared the environmental impact of single-use flexible ureteroscopes with reusable flexible ureteroscopes. An analysis of the typical life cycle of the LithoVue™ (Boston Scientific) single-use digital flexible ureteroscope and Olympus Flexible Video Ureteroscope (URV-F) was performed. To measure the carbon footprint, data were obtained on manufacturing of single-use and reusable flexible ureteroscopes and from typical uses obtained with a reusable scope, including repairs, replacement instruments, and ultimate disposal of both ureteroscopes. The solid waste generated (kg) and energy consumed (kWh) during each case were quantified and converted into their equivalent mass of carbon dioxide (kg of CO 2 ) released. Flexible ureteroscopic raw materials composed of plastic (90%), steel (4%), electronics (4%), and rubber (2%). The manufacturing cost of a flexible ureteroscope was 11.49 kg of CO 2 per 1 kg of ureteroscope. The weight of the single-use LithoVue and URV-F flexible ureteroscope was 0.3 and 1 kg, respectively. The total carbon footprint of the lifecycle assessment of the LithoVue was 4.43 kg of CO 2 per endourologic case. The total carbon footprint of the lifecycle of the reusable ureteroscope was 4.47 kg of CO 2 per case. The environmental impacts of the reusable flexible ureteroscope and the single-use flexible ureteroscope are comparable. Urologists should be aware that the typical life cycle of urologic instruments is a concerning source of environmental emissions.
Cost comparison of re-usable and single-use fibrescopes in a large English teaching hospital.
McCahon, R A; Whynes, D K
2015-06-01
A number of studies in the U.S.A. and mainland Europe have described the costs of fibreoptic tracheal intubation. However, no such data from the UK appear available. We performed a cost assessment of fibreoptic intubation, using re-usable (various devices from Olympus, Acutronic and Karl Storz) and single-use (Ambu aScope) fibrescopes, at the Queens Medical Centre, Nottingham, U.K., between 1 January 2009 and 31 March 2014. The total annual cost of fibreoptic intubation with re-usable fibrescopes was £46,385. Based on 141 fibreoptic intubations per year, this equated to £329 per use, an average dominated by repair/maintenance costs (43%) and capital depreciation costs (42%). In comparison, the total annual cost of using single-use fibrescopes for the same work would have been around £200 per use. The analysis enabled us to develop a generic model, wherein we were able to describe the relationship between total cost of use vs number of uses for a fibrescope. An 'isopleth' was identified for this relationship: a line that joined all the points where the cost of re-usable vs single-use fibrescopes was equal. It appears cheaper to use single-use fibrescopes at up to 200 fibreoptic intubations per year (a range commensurate with normal practice) even when the repair rate for re-usable fibrescopes is low. Any centre, knowing its fibrescope use and repair rate, can plot its data similarly to help ascertain which of the re-usable or single-use fibrescope represents better value. © 2015 The Association of Anaesthetists of Great Britain and Ireland.
Cost effective laparoendoscopic single-site surgery with a reusable platform.
Schwentner, C; Todenhöfer, T; Seibold, J; Alloussi, S; Aufderklamm, S; Mischinger, J; Stenzl, A; Gakis, G
2013-01-01
Many disposable platforms have been applied in laparoendoscopic single-site surgery (LESS). Besides technical issues, cost is one of the limiting factors for its widespread acceptance. The current study describes the first completely reusable LESS-platform. We performed LESS-procedures in 52 patients including nephrectomy (18), adrenalectomy (2), partial nephrectomy (3), pyeloplasty (4), renal cyst ablation (4), pelvic lymphadenectomy (15), and lymphocele ablation (6). All procedures were conducted using a novel reusable single-port device (X-Cone, Karl-Storz) with a simplified set of instruments. We obtained perioperative and demographic data, including a visual analogue pain scale (VAS), and a complication reporting system based on Clavien grading. Mean age was 50.04 y. Conversion to standard laparoscopy was necessary in 3 cases and addition of a needlescopic instrument in 6 cases. There was no open conversion. Intra- and postoperative complications occurred in 3 (Clavien II in 2 and III in 1) cases. Mean operative time was 110, 90, and 89 min, and hospital stay was 4.9, 3.1, and 3.6 d for nephrectomy, pelvic lymphadenectomy, and pyeloplasty, respectively. Mean VAS was 2.13, 1.07, and 1.5 while blood loss was 81.3 mL, 25.67 mL, and 17.5 mL, respectively. Mean lymph node yield was 15 (range, 8 to 21). A completely reusable LESS-platform is applicable to various uses in urology, yielding favorable functional and cosmetic results. Reusable materials are useful to reduce the cost of LESS, further increasing its acceptance. LESS with a completely reusable platform is more cost effective than standard laparoscopy.
Design and performance analysis of an aero-maneuvering orbital-transfer vehicle concept
NASA Technical Reports Server (NTRS)
Menees, G. P.
1985-01-01
Systems requirements for design-optimized, lateral-turn performance were determined for reusable, space-based applications and low-Earth orbits involving large multiple plane-inclination changes. The aerothermodynamic analysis is the most advanced available for rarefield-hypersonic flow over lifting surfaces at incidence. The effects of leading-edge bluntness, low-density viscous phenomena, and finite-rate flow-field chemistry and surface catalysis are accounted for. The predicted aerothermal heating characteristics are correlated with thermal-control and flight-performance capabilities. The mission payload capacity for delivery, retrieval, and combined operations was determined for round-trip sorties extending to polar orbits. Recommendations are given for future design refinements. The results help to identify technology issues required to develop prototype operational vehicles.
Materials Compatibility Testing in RSRM ODC: Free Cleaner Selection
NASA Technical Reports Server (NTRS)
Keen, Jill M.; Sagers, Neil W.; McCool, Alex (Technical Monitor)
2001-01-01
Government regulations have mandated production phase-outs of a number of solvents, including 1,1,1-trichloroethane, an ozone-depleting chemical (ODC). This solvent was used extensively in the production of the Reusable Solid Rocket Motors (RSRMs) for the Space Shuttle. Many tests have been performed to identify replacement cleaners. One major area of concern in the selection of a new cleaner has been compatibility. Some specific areas considered included cleaner compatibility with non-metallic surfaces, painted surfaces, support materials such as gloves and wipers as well as corrosive properties of the cleaners on the alloys used on these motors. The intent of this paper is to summarize the test logic, methodology, and results acquired from testing the many cleaner and material combinations.
Efficient magnetic recycling of covalently attached enzymes on carbon-coated metallic nanomagnets.
Zlateski, Vladimir; Fuhrer, Roland; Koehler, Fabian M; Wharry, Scott; Zeltner, Martin; Stark, Wendelin J; Moody, Thomas S; Grass, Robert N
2014-04-16
In the pursuit of robust and reusable biocatalysts for industrial synthetic chemistry, nanobiotechnology is currently taking a significant part. Recently, enzymes have been immobilized on different nanoscaffold supports. Carbon coated metallic nanoparticles were found to be a practically useful support for enzyme immobilization due to their large surface area, high magnetic saturation, and manipulatable surface chemistry. In this study carbon coated cobalt nanoparticles were chemically functionalized (diazonium chemistry), activated for bioconjugation (N,N-disuccinimidyl carbonate), and subsequently used in enzyme immobilization. Three enzymes, β-glucosidase, α-chymotrypsin, and lipase B were successfully covalently immobilized on the magnetic nonsupport. The enzyme-particle conjugates formed retained their activity and stability after immobilization and were efficiently recycled from milliliter to liter scales in short recycle times.
Optimal Thermal Design of a Multishield Thermal Protection System of Reusable Space Vehicles
NASA Astrophysics Data System (ADS)
Maiorova, I. A.; Prosuntsov, P. V.; Zuev, A. V.
2016-03-01
We have solved the problem of the optimal thermal design of a multishield thermal protection system of reusable space vehicles due to the choice of the optimal position and materials of radiation shields.
Thermal Protection System of the Space Shuttle
NASA Technical Reports Server (NTRS)
Cleland, John; Iannetti, Francesco
1989-01-01
The Thermal Protection System (TPS), introduced by NASA, continues to incorporate many of the advances in materials over the past two decades. A comprehensive, single-volume summary of the TPS, including system design rationales, key design features, and broad descriptions of the subsystems of TPS (E.g., reusable surface insulation, leading edge structural, and penetration subsystems) is provided. Details of all elements of TPS development and application are covered (materials properties, manufacturing, modeling, testing, installation, and inspection). Disclosures and inventions are listed and potential commercial application of TPS-related technology is discussed.
Improving Safety and Reliability of Space Auxiliary Power Units
NASA Technical Reports Server (NTRS)
Viterna, Larry A.
1998-01-01
Auxiliary Power Units (APU's) play a critical role in space vehicles. On the space shuttle, APU's provide the hydraulic power for the aerodynamic control surfaces, rocket engine gimballing, landing gear, and brakes. Future space vehicles, such as the Reusable Launch Vehicle, will also need APU's to provide electrical power for flight control actuators and other vehicle subsystems. Vehicle designers and mission managers have identified safety, reliability, and maintenance as the primary concerns for space APU's. In 1997, the NASA Lewis Research Center initiated an advanced technology development program to address these concerns.
Space Shuttle Orbiter auxiliary power unit
NASA Technical Reports Server (NTRS)
Mckenna, R.; Wicklund, L.; Baughman, J.; Weary, D.
1982-01-01
The Space Shuttle Orbiter auxiliary power units (APUs) provide hydraulic power for the Orbiter vehicle control surfaces (rudder/speed brake, body flap, and elevon actuation systems), main engine gimbaling during ascent, landing gear deployment and steering and braking during landing. Operation occurs during launch/ascent, in-space exercise, reentry/descent, and landing/rollout. Operational effectiveness of the APU is predicated on reliable, failure-free operation during each flight, mission life (reusability) and serviceability between flights (turnaround). Along with the accumulating flight data base, the status and results of efforts to achieve these long-run objectives is presented.
NASA Technical Reports Server (NTRS)
Edwards, S. F.; Kantsios, A. G.; Voros, J. P.; Stewart, W. F.
1975-01-01
The development of a radiometric technique for determining the spectral and total normal emittance of materials heated to temperatures of 800, 1100, and 1300 K by direct comparison with National Bureau of Standards (NBS) reference specimens is discussed. Emittances are measured over the spectral range of 1 to 15 microns and are statistically compared with NBS reference specimens. Results are included for NBS reference specimens, Rene 41, alundum, zirconia, AISI type 321 stainless steel, nickel 201, and a space-shuttle reusable surface insulation.
1980-02-06
ROCKWELL INTERNATIONAL TECHNICIANS MOUNT SOME OF THE NEARLY 8,000 CERAMIC-COATED TILES THAT REMAIN TO BE INSTALLED ON THE EXTERNAL SURFACES OF THE SPACE SHUTTLE ORBITER COLUMBIA TO COMPLETE THE THERMAL PROTECTION SYSTEM THAT WILL ABSORB THE INTENSE HEAT OF REENTERING THE EARTH'S ATMOSPHERE AFTER A MISSION IN SPACE. TILE INSTALLATION IS DONE ON AN AROUND-THE-CLOCK BASIS IN THE ORBITER PROCESSING FACILITY WHERE COLUMBIA, THE FIRST IN A NEW BREED OF MANNED, REUSABLE SPACECRAFT, IS BEING READIED FOR THE FIRST LAUNCH OF THE SPACE SHUTTLE LATER THIS YEAR.
1980-02-06
ROCKWELL INTERNATIONAL TECHNICIANS MOUNT SOME OF THE NEARLY 8,000 CERAMIC-COATED TILES THAT REMAIN TO BE INSTALLED ON THE EXTERNAL SURFACES OF THE SPACE SHUTTLE ORBITER COLUMBIA TO COMPLETE THE THERMAL PROTECTION SYSTEM THAT WILL ABSORB THE INTENSE HEAT OF REENTERING THE EARTH'S ATMOSPHERE AFTER A MISSION IN SPACE. TILE INSTALLATION IS DONE ON AN AROUND-THE-CLOCK BASIS IN THE ORBITER PROCESSING FACILITY WHERE COLUMBIA, THE FIRST IN A NEW BREED OF MANNED, REUSABLE SPACECRAFT, IS BEING READIED FOR THE FIRST LAUNCH OF THE SPACE SHUTTLE LATER THIS YEAR.
NASA Astrophysics Data System (ADS)
Hu, Jinyi; Yuan, Wei; Chen, Wenjun; Xu, Xiaotian; Tang, Yong
2016-12-01
This study reports the fabrication of a novel stable superhydrophobic and superoleophylic porous metal material on a copper fiber sintered felt (CFSF) substrate via a simple solution-immersion method. Oxidation and modification times are two important factors related to the level of hydrophobicity; oxidation for 1 h and modification for 24 h are appropriate to build a superhydrophobic CFSF surface with a water contact angle of 152.83° and a kerosene contact angle of 0°. The stability and high temperature resistance of superhydrophobic CFSF were studied. A novel device was designed to measure the water repellent ability of the treated CFSF. The results indicated that the water repellent ability of superhydrophobic CFSF was almost constant after 40 cycles of sanding. Both the water contact angle and the microstructure of the modified CFSF surface remained nearly unchanged after experiencing ultrasonic vibration for 1 min. The modified CFSF surface maintains super hydrophobicity after being treated at 180 °C for 1 h. The separation efficiencies for different types of oils and organic solvents (kerosene, chloroform, n-hexane and gasoline) are more than 96%. The modified CFSF retains a high robustness of separation efficiency even after it is recycled for the separation of kerosene and water for more than 10 times.
Functionalized C@TiO2 hollow spherical architecture for multifunctional applications.
Chattopadhyay, Shreyasi; Mishra, Manish Kr; De, Goutam
2016-03-28
Hierarchical anatase titania (TiO2) with a hollow spherical architecture decorated with functionalized carbon dots (C(F)@THS) was synthesized by a solvothermal decomposition of titanium(IV) isopropoxide (TTIP) in the presence of a solution mixture containing thiourea and citric acid. Interestingly, the concomitant presence of thiourea and citric acid has been found to be essential to obtain such hierarchical hollow architecture because individual constituents produced non-hollow spheres when hydrothermally treated with TTIP. The co-existence of these two constituents also accelerates the growth of hollow spheres. BET surface area study of C(F)@THS revealed the existence of a slit like mesoporosity with a surface area value of 81 m(2) g(-1). Time dependent FESEM and TEM studies confirmed the formation of nanoflake like structures in the intermediate stages followed by the growth of a hollow spherical architecture. We proposed that these nanoflakes get accumulated on the bubble surface to form such hollow spherical morphology. The PL spectral study and Raman shift of the as prepared C(F)@THS confirmed the presence of functionalized graphitic C dots on the surface. A thorough XPS analysis was conducted to explore the nature and relative atomic concentration of the functional groups (-COOH, -CONH2, -NH2). This C(F)@THS sample showed very fast and selective dye (methylene blue and methyl violet) adsorption ability (even from a mixture of two different dye solutions) due to these δ-site containing functional groups on the surface. As C(F)@THS showed only two times reusability for adsorption, the dye adsorbed C(F)@THS was calcined at 450 °C in air to yield organic free anatase TiO2 hollow spheres (THS) with a retention of the original structure. THS was recycled as an efficient and a reusable photocatalyst (k = 9.36 × 10(-2) min(-1)) as well as a photoanode in dye sensitized solar cells (DSSCs) having Jsc value of 19.58 mA cm(-2) with overall efficiency of 6.48%.
Just the Right Amount of Reinforcement
NASA Technical Reports Server (NTRS)
Walton, Greg
1998-01-01
Lockheed Martin Skunk Works, is taking the next step towards economical low-Earth-orbit (LEO) operations with NASA's X-33 technology demonstrator, that uses composite tanks for liquid hydrogen (LH sub2) fuel storage and structural support, The X-33 is a 53% scale model of the VentureStar single-stage-to-orbit (SSTO) reusable launch vehicle(RLV) projected to orbit payloads at a rate, of $1,000 per pound beginning in 2004 In order to make VentureStar completely reusable and economical engineers are using composite materials throughout the spacecrafts structure. The first test of the design comes in 1999 on the X-33 technology demonstrator. Two of the primary structures that engineers will be evaluating are the carbon fiber/epoxy LH2 fuel tanks. The 29-ft long by 18-ft wide tanks, which fill two-thirds of the X-33's interior, serve a dual purpose carrying fuel and providing structural support to the walls of the spacecraft. Fiber placement makes it possible to build the fuel tanks, large, light and strong enough to satisfy X33's requirements. Lockheed Martin choose the fabrication technology to produce the eight sections of each tank because of fiber placement's ability to handle complex surfaces, speed and repeatability.
Reusable High Aspect Ratio 3-D Nickel Shadow Mask
Shandhi, M.M.H.; Leber, M.; Hogan, A.; Warren, D.J.; Bhandari, R.; Negi, S.
2017-01-01
Shadow Mask technology has been used over the years for resistless patterning and to pattern on unconventional surfaces, fragile substrate and biomaterial. In this work, we are presenting a novel method to fabricate high aspect ratio (15:1) three-dimensional (3D) Nickel (Ni) shadow mask with vertical pattern length and width of 1.2 mm and 40 μm respectively. The Ni shadow mask is 1.5 mm tall and 100 μm wide at the base. The aspect ratio of the shadow mask is 15. Ni shadow mask is mechanically robust and hence easy to handle. It is also reusable and used to pattern the sidewalls of unconventional and complex 3D geometries such as microneedles or neural electrodes (such as the Utah array). The standard Utah array has 100 active sites at the tip of the shaft. Using the proposed high aspect ratio Ni shadow mask, the Utah array can accommodate 300 active sites, 200 of which will be along and around the shaft. The robust Ni shadow mask is fabricated using laser patterning and electroplating techniques. The use of Ni 3D shadow mask will lower the fabrication cost, complexity and time for patterning out-of-plane structures. PMID:29056835
Engineering of Neuron Growth and Enhancing Cell-Chip Communication via Mixed SAMs.
Markov, Aleksandr; Maybeck, Vanessa; Wolf, Nikolaus; Mayer, Dirk; Offenhäusser, Andreas; Wördenweber, Roger
2018-06-06
The interface between cells and inorganic surfaces represents one of the key elements for bioelectronics experiments and applications ranging from cell cultures and bioelectronics devices to medical implants. In the present paper, we describe a way to tailor the biocompatibility of substrates in terms of cell growth and to significantly improve cell-chip communication, and we also demonstrate the reusability of the substrates for cell experiments. All these improvements are achieved by coating the substrates or chips with a self-assembled monolayer (SAM) consisting of a mixture of organic molecules, (3-aminopropyl)-triethoxysilane and (3-glycidyloxypropyl)-trimethoxysilane. By varying the ratio of these molecules, we are able to tune the cell density and live/dead ratios of rat cortical neurons cultured directly on the mixed SAM as well as neurons cultured on protein-coated SAMs. Furthermore, the use of the SAM leads to a significant improvement in cell-chip communications. Action potential signals of up to 9.4 ± 0.6 mV (signal-to-noise ratio up to 47) are obtained for HL-1 cells on microelectrode arrays. Finally, we demonstrate that the SAMs facilitate a reusability of the samples for all cell experiments with little re-processing.
Liu, Y Y; Zhao, Y H; Zhou, Y; Guo, X L; Chen, Z T; Zhang, W J; Zhang, Y; Chen, J; Wang, Z M; Sun, L T; Zhang, T
2018-08-03
Noble metal nanoparticles (NPs) such as Au and Ag have shown many applications in the field of catalysis, sensing etc. due to their excellent photoelectric properties. But agglomeration and a low recovery rate are big problems for their applications. In this research, a novel Ag NPs/graphene (reduced graphene oxide)-loading loofah sponge (Ag NPs/RGO-LS) was synthesized through a one-step reduction method. Where the RGO is used as a nano-support with the high specific surface area and the high conductivity to prevent the agglomeration of Ag NPs and provide a conductive layer. The natural, green, low-cost and high-yield LS is designed as a macro-support to reduce the loss of Ag NPs during recycling. The as-prepared Ag NPs/RGO-LS is stable, uniform, and exhibits high efficiency and reusability in the catalytic reduction of 4-nitrophenol (4-NP) with a high rate constant of 1.893 min -1 as well as an average conversion of 98% in 6 min during five cycles. The results have not only paved the way for the wide application of Ag NPs but also provide a new road for the application of other metal NPs.
X33 Reusable Launch Vehicle Control on Sliding Modes: Concepts for a Control System Development
NASA Technical Reports Server (NTRS)
Shtessel, Yuri B.
1998-01-01
Control of the X33 reusable launch vehicle is considered. The launch control problem consists of automatic tracking of the launch trajectory which is assumed to be optimally precalculated. It requires development of a reliable, robust control algorithm that can automatically adjust to some changes in mission specifications (mass of payload, target orbit) and the operating environment (atmospheric perturbations, interconnection perturbations from the other subsystems of the vehicle, thrust deficiencies, failure scenarios). One of the effective control strategies successfully applied in nonlinear systems is the Sliding Mode Control. The main advantage of the Sliding Mode Control is that the system's state response in the sliding surface remains insensitive to certain parameter variations, nonlinearities and disturbances. Employing the time scaling concept, a new two (three)-loop structure of the control system for the X33 launch vehicle was developed. Smoothed sliding mode controllers were designed to robustly enforce the given closed-loop dynamics. Simulations of the 3-DOF model of the X33 launch vehicle with the table-look-up models for Euler angle reference profiles and disturbance torque profiles showed a very accurate, robust tracking performance.
Orbiting Depot and Reusable Lander for Lunar Transportation
NASA Technical Reports Server (NTRS)
Petro, Andrew
2009-01-01
A document describes a conceptual transportation system that would support exploratory visits by humans to locations dispersed across the surface of the Moon and provide transport of humans and cargo to sustain one or more permanent Lunar outpost. The system architecture reflects requirements to (1) minimize the amount of vehicle hardware that must be expended while maintaining high performance margins and (2) take advantage of emerging capabilities to produce propellants on the Moon while also enabling efficient operation using propellants transported from Earth. The system would include reusable single- stage lander spacecraft and a depot in a low orbit around the Moon. Each lander would have descent, landing, and ascent capabilities. A crew-taxi version of the lander would carry a pressurized crew module; a cargo version could carry a variety of cargo containers. The depot would serve as a facility for storage and for refueling with propellants delivered from Earth or propellants produced on the Moon. The depot could receive propellants and cargo sent from Earth on a variety of spacecraft. The depot could provide power and orbit maintenance for crew vehicles from Earth and could serve as a safe haven for lunar crews pending transport back to Earth.
Merits of full flow vs. conventional staged combustion cycles for reusable launch vehicle propulsion
NASA Astrophysics Data System (ADS)
Peery, Steven D.; Parsley, Randy C.
1996-03-01
This paper provides a comparison between full-flow and conventional staged combustion thermodynamic O2/H2 rocket engine cycles for Reusable Launch Vehicle, RLV, single-stage-to-orbit applications. The impact of the cycle thermodynamics, component configuration, and component operating parameters on engine performance and weight for the two approaches is presented. Both cycles were modeled with equivalent technology turbomachinery and chamber/nozzle RLV life requirements. The first order impact of cycle selection, pump exit pressure, and turbine temperature on the empty weight of an SSTO Reusable Launch Vehicle is presented.
Cryopumping in Cryogenic Insulations for a Reusable Launch Vehicle
NASA Technical Reports Server (NTRS)
Johnson, Theodore F.; Weiser, Erik S.; Grimsley, Brian W.; Jensen, Brian J.
2003-01-01
Testing at cryogenic temperatures was performed to verify the material characteristics and manufacturing processes of reusable propellant tank cryogenic insulations for a Reusable Launch Vehicle (RLV). The unique test apparatus and test methods developed for the investigation of cryopumping in cryogenic insulations are described. Panel level test specimens with various types of cryogenic insulations were subjected to a specific thermal profile where the temperature varied from -262 C to 21 C. Cryopumping occurred if the interior temperature of the specimen exhibited abnormal temperature fluctuations, such as a sudden decrease in temperature during the heating phase.
Van Devender, J.P.; Emin, D.
1983-12-21
A reusable fast opening switch for transferring energy, in the form of a high power pulse, from an electromagnetic storage device such as an inductor into a load. The switch is efficient, compact, fast and reusable. The switch comprises a ferromagnetic semiconductor which undergoes a fast transition between conductive and metallic states at a critical temperature and which undergoes the transition without a phase change in its crystal structure. A semiconductor such as europium rich europhous oxide, which undergoes a conductor to insulator transition when it is joule heated from its conductor state, can be used to form the switch.
Reusable thermal protection system development: A prospective
NASA Technical Reports Server (NTRS)
Goldstein, Howard
1992-01-01
The state of the art in passive reusable thermal protection system materials is described. Development of the Space Shuttle Orbiter, which was the first reusable vehicle, is discussed. The thermal protection materials and given concepts and some of the shuttle development and manufacturing problems are described. Evolution of a family of grid and flexible ceramic external insulation materials from the initial shuttle concept in the early 1970's to the present time is described. The important properties and their evolution are documented. Application of these materials to vehicles currently being developed and plans for research to meet the space programs future needs are summarized.
Van Devender, John P.; Emin, David
1986-01-01
A reusable fast opening switch for transferring energy, in the form of a high power pulse, from an electromagnetic storage device such as an inductor into a load. The switch is efficient, compact, fast and reusable. The switch comprises a ferromagnetic semiconductor which undergoes a fast transition between conductive and insulating states at a critical temperature and which undergoes the transition without a phase change in its crystal structure. A semiconductor such as europium rich europhous oxide, which undergoes a conductor to insulator transition when it is joule heated from its conductor state, can be used to form the switch.
Reusable cryogenic foam insulation for advanced aerospace vehicles
NASA Technical Reports Server (NTRS)
Mcauliffe, Patrick S.; Taylor, Allan H.; Sparks, Larry L.; Dube, William P.
1991-01-01
Future high-speed aircraft and aerospace vehicles using cryogenic propellants will require an advanced reusable insulation system for the propellant tank structure. This cryogenic insulation system must be lightweight, structurally and thermally efficient, and capable of multiple reuse without cracking or degraded performance. This paper presents recent progress in the development of a reusable cryogenic foam insulation system having a maximum service temperature of 400 F. The system consists of preshaped, precut blocks of rigid polymethacrylimide foam insulation, wrapped with a high-temperature Kapton and aluminum foil vapor barrier which is adhesively bonded to the propellant tank wall.
Gupta, Deepak; Wang, Hong
2011-12-01
To calculate the costs per intubation of reusable fiberoptic scopes versus single-use intubation scopes. Open-label retrospective study. University-affiliated hospital. The one-year intubation records of intubations performed with reusable intubation scopes, the one-year maintenance costs of these scopes, and their three-year repair cost records were analyzed. A total of 166 intubations were performed with reusable fiberoptic scopes in 2009. Calculations to assess the costs per intubation based on the documented records at our institution were made. The total cost of an intubation, the repair-to-intubation ratio, and the repair cost per intubation were determined. The total cost of an intubation at our institution in 2009, using reusable scopes, was $119.75 [US dollars (USD)], which included $20.15 (purchasing), $53.48 (repair), $33.16 (maintenance), and $12.96 (labor). The repair-to-intubation ratio was 1:55. Repair costs were $53.48 per intubation and $2,959.44 per instance of repair. The Ambu aScope, a single-use intubation scope, is a new addition to video laryngoscopy. The price should range within 10% of our intubation cost ($120.00 to $132.00 per single-use intubation scope). Copyright © 2011 Elsevier Inc. All rights reserved.
Zhu, Min; Chen, Ruxue; Zhong, Shaobo; Qian, Yangming; Huang, Quanyi
2017-02-01
This research aims to associate the allocation of medical resources with the function of the modular organization and the possible needs for humanitarian assistance missions. The overseas humanitarian medical assistance mission, which was sent after a disaster on the hospital ship Peace Ark, part of China's People's Liberation Army (PLA) Navy, was considered as study model. The cases used for clustering and matching sample formation were randomly selected from the existing information related to Peace Ark's mission. Categories of the reusable resources clustered by this research met the requirement of the actual consumption almost completely (more than 95%) and the categories of non-reusable resources met the requirement by more than 80%. In the mission's original resource preparing plan, more than 30% of the non-reusable resource categories remained unused during the mission. In the original resource preparing plan, some key non-reusable resources inventories were completely exhausted at the end of the mission, while 5% to 30% of non-reusable resources remained in the resource allocation plan generated by this research at the end of the mission. The medical resource allocation plan generated here can enhance the supporting level for the humanitarian assistance mission. This research could lay the foundation for an assistant decision-making system for humanitarian assistance mission.
Development Status of Reusable Rocket Engine
NASA Astrophysics Data System (ADS)
Yoshida, Makoto; Takada, Satoshi; Naruo, Yoshihiro; Niu, Kenichi
A 30-kN rocket engine, a pilot engine, is being developed in Japan. Development of this pilot engine has been initiated in relation to a reusable sounding rocket, which is also being developed in Japan. This rocket takes off vertically, reaches an altitude of 100 km, lands vertically at the launch site, and is launched again within several days. Due to advantage of reusability, successful development of this rocket will mean that observation missions can be carried out more frequently and economically. In order to realize this rocket concept, the engines installed on the rocket should be characterized by reusability, long life, deep throttling and health monitoring, features which have not yet been established in Japanese rocket engines. To solve the engineering factors entitled by those features, a new design methodology, advanced engine simulations and engineering testing are being focused on in the pilot engine development stage. Especially in engineering testing, limit condition data is acquired to facilitate development of new diagnostic techniques, which can be applied by utilizing the mobility of small-size hardware. In this paper, the development status of the pilot engine is described, including fundamental design and engineering tests of the turbopump bearing and seal, turbine rig, injector and combustion chamber, and operation and maintenance concepts for one hundred flights by a reusable rocket are examined.
Packaging Software Assets for Reuse
NASA Astrophysics Data System (ADS)
Mattmann, C. A.; Marshall, J. J.; Downs, R. R.
2010-12-01
The reuse of existing software assets such as code, architecture, libraries, and modules in current software and systems development projects can provide many benefits, including reduced costs, in time and effort, and increased reliability. Many reusable assets are currently available in various online catalogs and repositories, usually broken down by disciplines such as programming language (Ibiblio for Maven/Java developers, PyPI for Python developers, CPAN for Perl developers, etc.). The way these assets are packaged for distribution can play a role in their reuse - an asset that is packaged simply and logically is typically easier to understand, install, and use, thereby increasing its reusability. A well-packaged asset has advantages in being more reusable and thus more likely to provide benefits through its reuse. This presentation will discuss various aspects of software asset packaging and how they can affect the reusability of the assets. The characteristics of well-packaged software will be described. A software packaging domain model will be introduced, and some existing packaging approaches examined. An example case study of a Reuse Enablement System (RES), currently being created by near-term Earth science decadal survey missions, will provide information about the use of the domain model. Awareness of these factors will help software developers package their reusable assets so that they can provide the most benefits for software reuse.
NASA Astrophysics Data System (ADS)
Bossu, R.; Lefebvre, S.; Mazet-Roux, G.; Roussel, F.
2012-12-01
This paper presents an after the fact study of the Virginia earthquake of 2011 August 23 using only the traffic observed on the EMSC website within minutes of its occurrence. Although the EMSC real time information services remain poorly identified in the US, a traffic surge was observed immediately after the earthquake's occurrence. Such surges, known as flashcrowd and commonly observed on our website after felt events within the Euro-Med region are caused by eyewitnesses looking for information about the shaking they have just felt. EMSC developed an approach named flashsourcing to map the felt area, and in some circumstances, the regions affected by severe damage or network disruption. The felt area is mapped simply by locating the Internet Protocol (IP) addresses of the visitors to the website during these surges while the existence of network disruption is detected by the instantaneous loss at the time of earthquake's occurrence of existing Internet sessions originating from the impacted area. For the Virginia earthquake, which was felt at large distances, the effects of the waves propagation are clearly observed. We show that the visits to our website are triggered by the P waves arrival: the first visitors from a given locality reach our website 90s after their location was shaken by the P waves. From a processing point of view, eyewitnesses can then be considered as ground motion detectors. By doing so, the epicentral location is determined through a simple dedicated location algorithm within 2 min of the earthquake's occurrence and 30 km accuracy. The magnitude can be estimated in similar time frame by using existing empirical relationships between the surface of the felt area and the magnitude. Concerning the effects of the earthquake, we check whether one can discriminate localities affected by strong shaking from web traffic analysis. This is actually the case. Localities affected by strong level of shaking exhibit higher ratio of visitors to the number of inhabitants than localities having experienced weak ground motion. In other words, we observe higher proportion of visitors from localities where the earthquake was widely felt when compared to localities where it was scarcely felt. This opens the way to automatically map the relative level of shaking within minutes of an earthquake's occurrence. In conclusion, the study of the Virginia earthquake shows that eyewitnesses' visits to our website follow the arrival of the P waves at their location. This further demonstrates the real time public desire of information after felt earthquakes, a parameter which should be integrated in the definition of earthquake information services. It also reveals additional capabilities of the flashsourcing method. Earthquakes felt at large distances i.e. where the propagation time to the most distant eyewitnesses exceeds a couple of minutes, can be located and their magnitude estimated in a time frame comparable to the one of automatic seismic locations by real time seismic networks. It also provides very rapid indication on the effects of the earthquakes, by mapping the felt area, detecting the localities affected by network disruption and mapping the relative level of shaking. Such information are essential to improve situation awareness, constrain real time scenario and in in turn, contribute to improved earthquake response.
NASA Technical Reports Server (NTRS)
Taylor, Shawn C.; DeMange, Jeffrey J.; Dunlap, Patrick H., Jr.; Steinetz, Bruce M.
2006-01-01
Knitted metallic spring tubes are the structural backbones that provide resiliency in control surface seals for use on current and future reusable space launch vehicles. Control surface seals fill the space between movable control surfaces such as body flaps, rudders and elevons, and the static body structures to which they are attached. These seals must remain in continuous contact with opposing surfaces to prevent the ingestion of damaging hot gases encountered during atmospheric re-entry. The Inconel X-750 (Special Metals Corporation) spring tube utilized in the baseline control surface seal shows significant resiliency loss when compressed at temperatures as low as 1200 F. High temperature compression testing and microstructural analysis show that creep is the dominant deformation mechanism leading to permanent set and resiliency loss in tested spring tube samples. Additional evaluation using a structured design of experiments approach shows that spring tube performance, primarily high temperature resiliency, can be enhanced through material substitution of Rene 41 (Allvac) alloy (for the baseline Inconel X-750 material) when coupled with specialized thermal processing.
Catalysis study for space shuttle vehicle thermal protection systems. [for vehicle surface
NASA Technical Reports Server (NTRS)
Breen, J.; Rosner, D. E.; Delgass, W. N.; Nordine, P. C.; Cibrian, R.; Krishnan, N. G.
1973-01-01
Experimental results on the problem of reducing aerodynamic heating on space shuttle orbiter surfaces are presented. Data include: (1) development of a laboratory flow reactor technique for measuring gamma sub O and gamma sub N on candidate materials at surfaces, T sub w, in the nominal range 1000 to 2000, (2) measurements of gamma sub O and gamma sub N above 1000 K for both the glass coating of a reusable surface insulation material and the siliconized surface of a reinforced pyrolyzed plastic material, (3) measurement of the ablation behavior of the coated RPP material at T sub w is greater than or equal to 2150 K, (4) X-ray photoelectron spectral studies of the chemical constituents on these surfaces before and after dissociated gas exposure, (5) scanning electron micrograph examination of as-received and reacted specimens, and (6) development and exploitation of a method of predicting the aerodynamic heating consquences of these gamma sub O(T sub w) and gamma sub N(T sub w) measurements for critical locations on a radiation cooled orbiter vehicle.
76 FR 45268 - Reprocessing of Reusable Medical Devices
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-28
... personal information provided. For additional information on submitting comments, see the ``Comments... problems in all steps of medical device reprocessing,\\1\\ including cleaning, disinfecting, and sterilizing... following issues: 1. What are the nature, scope, and impact of reusable medical device reprocessing problems...
Structural Integrity and Durability of Reusable Space Propulsion Systems
NASA Technical Reports Server (NTRS)
1987-01-01
A two-day conference on the structural integrity and durability of reusable space propulsion systems was held on May 12 and 13, 1987, at the NASA Lewis research Center. Aerothermodynamic loads; instrumentation; fatigue, fracture, and constitutive modeling; and structural dynamics were discussed.
Design and evaluation of an energy-absorbing, reusable roadside/median barrier.
DOT National Transportation Integrated Search
2015-07-01
Further design and evaluation was conducted on an energy-absorbing, restorable and reusable roadside/median barrier, : designated the RESTORE barrier. A series of dynamic component tests were conducted on 11-in. (295-mm) tall x 10-in. : (254-mm) w...
NASA Technical Reports Server (NTRS)
1991-01-01
The Reusable Reentry Satellite (RRS) System is composed of the payload segment (PS), vehicle segment (VS), and mission support (MS) segments. This specification establishes the performance, design, development, and test requirements for the RRS Rodent Module (RM).
75 FR 20874 - Agency Information Collection Activity Seeking OMB Approval
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-21
... to issue Experimental Permits for reusable suborbital rockets to authorize launches for the purpose... Suborbital Rockets. Type of Request: Extension without change of a currently approved collection. OMB Control... FAA's new authority to issue Experimental Permits for reusable [[Page 20875
Hosseini, Seyed Hassan; Hosseini, Seyedeh Ameneh; Zohreh, Nasrin; Yaghoubi, Mahshid; Pourjavadi, Ali
2018-01-31
A magnetic nanocomposite was prepared by entrapment of Fe 3 O 4 nanoparticles into the cross-linked ionic liquid/epoxy type polymer. The resulting support was used for covalent immobilization of cellulase through the reaction with epoxy groups. The ionic surface of the support improved the adsorption of enzyme, and a large amount of enzyme (106.1 mg/g) was loaded onto the support surface. The effect of the presence of ionic monomer and covalent binding of enzyme was also investigated. The structure of support was characterized by various instruments such as FT-IR, TGA, VSM, XRD, TEM, SEM, and DLS. The activity and stability of immobilized cellulase were investigated in the prepared support. The results showed that the ionic surface and covalent binding of enzyme onto the support improved the activity, thermal stability, and reusability of cellulase compared to free cellulase.
Aerodynamic heating on AFE due to nonequilibrium flow with variable entropy at boundary layer edge
NASA Technical Reports Server (NTRS)
Ting, P. C.; Rochelle, W. C.; Bouslog, S. A.; Tam, L. T.; Scott, C. D.; Curry, D. M.
1991-01-01
A method of predicting the aerobrake aerothermodynamic environment on the NASA Aeroassist Flight Experiment (AFE) vehicle is described. Results of a three dimensional inviscid nonequilibrium solution are used as input to an axisymmetric nonequilibrium boundary layer program to predict AFE convective heating rates. Inviscid flow field properties are obtained from the Euler option of the Viscous Reacting Flow (VRFLO) code at the boundary layer edge. Heating rates on the AFE surface are generated with the Boundary Layer Integral Matrix Procedure (BLIMP) code for a partially catalytic surface composed of Reusable Surface Insulation (RSI) times. The 1864 kg AFE will fly an aerobraking trajectory, simulating return from geosynchronous Earth orbit, with a 75 km perigee and a 10 km/sec entry velocity. Results of this analysis will provide principal investigators and thermal analysts with aeroheating environments to perform experiment and thermal protection system design.
Steady internal flow and aerodynamic loads analysis of shuttle thermal protection system
NASA Technical Reports Server (NTRS)
Petley, D. H.; Alexander, W., Jr.; Ivey, G. W., Jr.; Kerr, P. A.
1984-01-01
An analytical model for calculation of ascent steady state tile loading was developed and validated with wind tunnel data. The analytical model is described and results are given. Results are given for loading due to shocks and skin friction. The analysis included calculation of internal flow (porous media flow and channel flow) to obtain pressures and integration of the pressures to obtain forces and moments on an insulation tile. A heat transfer program was modified by using analogies between heat transfer and fluid flow so that it could be used for internal flow calculation. The type of insulation tile considered was undensified reusable surface insulation (RSI) without gap fillers, and the location studied was the lower surface of the orbiter. Force and moment results are reported for parameter variations on surface pressure distribution, gap sizes, insulation permeability, and tile thickness.
Self-Healing Nanocomposites for Reusable Composite Cryotanks
NASA Technical Reports Server (NTRS)
Eberly, Daniel; Ou, Runqing; Karcz, Adam; Skandan, Ganesh
2013-01-01
Composite cryotanks, or composite overwrapped pressure vessels (COPVs), offer advantages over currently used aluminum-lithium cryotanks, particularly with respect to weight savings. Future NASA missions are expected to use COPVs in spaceflight propellant tanks to store fuels, oxidizers, and other liquids for launch and space exploration vehicles. However, reliability, reparability, and reusability of the COPVs are still being addressed, especially in cryogenic temperature applications; this has limited the adoption of COPVs in reusable vehicle designs. The major problem with composites is the inherent brittleness of the epoxy matrix, which is prone to microcrack formation, either from exposure to cryogenic conditions or from impact from different sources. If not prevented, the microcracks increase gas permeation and leakage. Accordingly, materials innovations are needed to mitigate microcrack damage, and prevent damage in the first place, in composite cryotanks. The self-healing technology being developed is capable of healing the microcracks through the use of a novel engineered nanocomposite, where a uniquely designed nanoparticle additive is incorporated into the epoxy matrix. In particular, this results in an enhancement in the burst pressure after cryogenic cycling of the nanocomposite COPVs, relative to the control COPVs. Incorporating a novel, self-healing, epoxy-based resin into the manufacture of COPVs allows repeatable self-healing of microcracks to be performed through the simple application of a low-temperature heat source. This permits COPVs to be reparable and reusable with a high degree of reliability, as microcracks will be remediated. The unique phase-separated morphology that was imparted during COPV manufacture allows for multiple self-healing cycles. Unlike single-target approaches where one material property is often improved at the expense of another, robustness has been introduced to a COPV by a combination of a modified resin and nanoparticle additives. Unique nanoparticles were used that have been surface-functionalized to be compatible with the resin. Both organic and inorganic components toughen the matrix and result in a more impact-resistant COPV. In one resin system containing an inorganic nanomaterial additive, a significant improvement in burst performance was observed after the COPV was cryo-impact-damaged and then self-healed, with a greater than 10% improvement in burst pressure after the self-healing process was performed. Initial cross-sectional analysis via microscopy showed good resin infiltration of the carbon fibers and without voids. To further enhance the capability between the nanomaterial additives and the resin, a surface modification was successfully performed. A second specialty epoxy resin was prepared using a surface modified nanomaterial additive, and COPVs were fabricated. Steps were taken to improve the mechanical properties of the COPVs by using a low-viscosity resin system that contained a different curing agent. This lower viscosity improves the processing of the COPV, and preliminary results show that the burst pressure of these new vessels is 20 to 25% higher than that of the original. The self-healing concept demonstrated in this research and development effort represents a platform technology, and the self-healing property is neither restricted to the particular epoxy system used here, nor to the COPV application. Self-healing is a direct result of a unique phase separated morphology created via the resin and is aided by the nanoparticles. The self-healing function can be introduced to other customer-specific resin systems in coating, bulk, or composite applications provided that the unique phase separated morphology can be enabled in those systems.
Single use disposable digital flexible ureteroscopes: an ex-vivo assessment and cost analysis.
Hennessey, D B; Fojecki, G; Papa, N; Lawrentschuk, N; Bolton, D
2018-04-15
The single use flexible ureteroscope (fURS), the LithoVue is an important recent development. We aim to measure the capability of this instrument and to assess if there is a benefit to switching to single use instruments. The LithoVue was compared to Olympus URF-V and Stortz Flex Xc ex-vivo. An analysis of reusable fURS usage was performed to evaluate damage, durability and maintenance costs. This was then compared to the projected costs of using single use instruments. Flexion, deflection and irrigation flow of the LithoVue was equivalent, if not better than reusable instruments. An analysis of 234 procedures with 7 new Olympus URF-V scopes, revealed 15 scope damages. Staghorn stones and lower pole/midzone stones were significant risk factors for damage, p=0.014. Once damage occurred, it was likely to occur again. Total repair costs were $162,628 (£92,411), the mean cost per case is $695 (£395). Factoring in the purchase cost, cleaning and repair costs, and the cumulative cost of 28 reusable fURS cases is approximately $50,000 (£28,412). If the LithoVue was priced at $1200 AUD, switching to a single use scope would cost approximately $35,000 (£19,888). The LithoVue is analogous to reusable fURS scopes in regard to standard technical metrics. Depending on its purchase cost it may also represent a cost saving for hospitals when compared to the cumulative costs of maintaining reusable fURS. Additionally, urologist may consider to use the scope in cases in which reusable scope damage is anticipated. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Schlager, Daniel; Hein, Simon; Obaid, Moaaz Abdulghani; Wilhelm, Konrad; Miernik, Arkadiusz; Schoenthaler, Martin
2017-11-01
To evaluate and compare Flexor ® Vue™, a semidisposable endoscopic deflection system with disposable ureteral sheath and reusable visualization source, and a nondisposable fiber optic ureteroscope in a standard in vitro setting. FlexorVue and a reusable fiber optic flexible ureteroscope were each tested in an artificial kidney model. The experimental setup included the visualization of colored pearls and the extraction of calculi with two different extraction devices (NCircle ® and NGage ® ). The procedures were performed by six experienced surgeons. Visualization time, access to calices, successful stone retraction, and time required were recorded. In addition, the surgeons' workload and subjective performance were determined according to the National Aeronautics and Space Administration-task load index (NASA-TLX). We referred to the Likert scale to assess maneuverability, handling, and image quality. Nearly all calices (99%) were correctly identified using the reusable scope, indicating full kidney access, whereas 74% of the calices were visualized using FlexorVue, of which 81% were correctly identified. Access to the lower poles of the kidney model was significantly less likely with the disposable device, and time to completion was significantly longer (755 s vs 153 s, p < 0.001). The stone clearance success rate with the disposable device was 23% using the NGage and 13% using the NCircle basket. Overall NASA-TLX scores were significantly higher using FlexorVue. The conventional reusable device also demonstrated superior maneuverability, handling, and image quality. FlexorVue offers a semidisposable deflecting endoscopic system allowing basic ureteroscopic and cystoscopic procedures. For its use as an addition or replacement for current reusable scopes, it requires substantial technical improvements.
Amour, Julien; Le Manach, Yannick Le; Borel, Marie; Lenfant, François; Nicolas-Robin, Armelle; Carillion, Aude; Ripart, Jacques; Riou, Bruno; Langeron, Olivier
2010-02-01
Single-use metal laryngoscope blades are cheaper and carry a lower risk of infection than reusable metal blades. The authors compared single-use and reusable metal blades during rapid sequence induction of anesthesia in a multicenter cluster randomized trial. One thousand seventy-two adult patients undergoing general anesthesia under emergency conditions and requiring rapid sequence induction were randomly assigned on a weekly basis to either single-use or reusable metal blades (cluster randomization). After induction, a 60-s period was allowed to complete intubation. In the case of failed intubation, a second attempt was performed using the opposite type of blade. The primary endpoint was the rate of failed intubation, and the secondary endpoints were the incidence of complications (oxygen desaturation, lung aspiration, and/or oropharynx trauma) and the Cormack and Lehane score. Both groups were similar in their main characteristics, including the risk factors for difficult intubation. The rate of failed intubation was significantly decreased with single-use metal blades at the first attempt compared with reusable blades (2.8 vs. 5.4%, P < 0.05). In addition, the proportion of grades III and IV in Cormack and Lehane score were also significantly decreased with single-use metal blades (6 vs. 10%, P < 0.05). The global complication rate did not reach statistical significance, although the same trend was noted (6.8% vs. 11.5%, P = not significant). An investigator survey and a measure of illumination pointed that illumination might have been responsible for this result. The single-use metal blade was more efficient than a reusable metal blade in rapid sequence induction of anesthesia.
Knösel, Michael; Mattysek, Simone; Jung, Klaus; Kubein-Meesenburg, Dietmar; Sadat-Khonsari, Reza; Ziebolz, Dirk
2010-07-01
To test the null hypothesis that there are no significant differences in the reusability of debonded brackets with regard to debonding technique and adhesive used. Ninety-six osteotomed third molars were randomly assigned to two study groups (n = 48) for bonding of a 0.018-inch bracket (Ormesh, Ormco) with either a composite adhesive (Mono-Lok2; RMO) or a glass ionomer cement (GIC; Fuji Ortho LC;GC). Each of these two groups were then randomly divided into four subgroups (n = 12) according to the method of debonding using (1) bracket removal pliers (BRP; Dentaurum), (2) a side cutter (SC; Dentaurum), (3) a lift-off debracketing instrument (LODI; 3M-Unitek), or (4) an air pressure pulse device (CoronaFlex; KaVo). The brackets were subsequently assessed visually for reusability and reworkability with 2x magnification and by pull testing with a 0.017- x 0.025-inch steel archwire. The proportions of reusable brackets were individually compared in terms of mode of removal and with regard to adhesives using the Fisher exact test (alpha = 5%). The null hypothesis was rejected. Not taking into account the debonding method, brackets bonded with GIC were judged to a significant extent (81%; n = 39; P < .01) to be reworkable compared with those bonded with composite (56%; n = 27). All brackets in both adhesive groups removed with either the LODI or the CoronaFlex were found to be reusable, whereas 79% (46%) of the brackets removed with the BRP (SC) were not. The proportion of reusable brackets differed significantly between modes of removal (P < .01). With regard to bracket reusability, the SC and the BRP cannot be recommended for debonding brackets, especially in combination with a composite adhesive.
Toh, Ming Ren; Chew, Lita
2017-01-01
Unused medicines represent a major source of wastage in healthcare systems around the world. Previous studies have suggested the potential cost savings from recycling the waste medicines. However, issues of product safety and integrity often deter healthcare institutions from recycling donated medications. To evaluate the feasibility of medication recycling and to assess the actual cost savings from recycling waste medicines and whether reusability of waste medicines differed among various drug classes and donor sources. Donated medications from hospitals, private medical clinics and patients were collected and assessed using a medication recycling protocol in a hospice care setting from November 2013 through January 2014. Costs were calculated using a reference pricing list from a public hospital. A total of 244 donations, amounting to 20,759 dosage units, were collected during the study period. Most donations (90.8%) were reusable, providing a total of S$5266 in cost savings. Less than 2 h daily was spent by a single pharmacy technician on the sorting and distributing processes. Medications donated by health facilities were thrice more likely to be reusable than those by patients (odds ratio = 3.614, 95% confidence interval = 3.127, 4.176). Medications belonging to Anatomical Therapeutic Chemical class G (0.0%), H (8.2%) and L (30.0%) were the least reusable. Most donated medications were reusable. The current protocol can be further streamlined to focus on the more reusable donor sources and drug classes and validated in other settings. Overall, we opine that it is feasible to practise medication recycling on a larger scale to reduce medication wastage.
Hidalgo, D; Sacco, A; Hernández, S; Tommasi, T
2015-11-01
A mixed microbial population naturally presents in seawater was used as active anodic biofilm of two Microbial Fuel Cells (MFCs), employing either a 2D commercial carbon felt or 3D carbon-coated Berl saddles as anode electrodes, with the aim to compare their electrochemical behavior under continuous operation. After an initial increase of the maximum power density, the felt-based cell reduced its performance at 5 months (from 7 to 4 μW cm(-2)), while the saddle-based MFC exceeds 9 μW cm(-2) (after 2 months) and maintained such performance for all the tests. Electrochemical impedance spectroscopy was used to identify the MFCs controlling losses and indicates that the mass-transport limitations at the biofilm-electrolyte interface have the main contribution (>95%) to their internal resistance. The activation resistance was one order of magnitude lower with the Berl saddles than with carbon felt, suggesting an enhanced charge-transfer in the high surface-area 3D electrode, due to an increase in bacteria population growth. Copyright © 2015 Elsevier Ltd. All rights reserved.
Reusable chelating resins concentrate metal ions from highly dilute solutions
NASA Technical Reports Server (NTRS)
Bauman, A. J.; Weetal, H. H.; Weliky, N.
1966-01-01
Column chromatographic method uses new metal chelating resins for recovering heavy-metal ions from highly dilute solutions. The absorbed heavy-metal cations may be removed from the chelating resins by acid or base washes. The resins are reusable after the washes are completed.
Critical parts are stored and shipped in environmentally controlled reusable container
NASA Technical Reports Server (NTRS)
Kummerfeld, K. R.
1966-01-01
Environmentally controlled, hermetically sealed, reusable metal cabinet with storage drawers is used to ship and store sensitive electronic, pneumatic, or hydraulic parts or medical supplies under extreme weather or handling conditions. This container is compatible with on-site and transportation handling facilities.
Code of Federal Regulations, 2010 CFR
2010-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Code of Federal Regulations, 2012 CFR
2012-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Code of Federal Regulations, 2014 CFR
2014-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Code of Federal Regulations, 2013 CFR
2013-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Code of Federal Regulations, 2011 CFR
2011-01-01
... suborbital rocket to the effects of altitude, velocity, acceleration, or burn duration that exceed a level or... area, that a reusable suborbital rocket's instantaneous impact point may not traverse. Key flight... permitted flights may take place. Permitted vehicle means a reusable suborbital rocket operated by a launch...
Xie, Yingying; Fang, Zhanqiang; Qiu, Xinhong; Tsang, Eric Pokeung; Liang, Bin
2014-08-01
Our previous reports showed that nano zero-valent iron (nZVI), steel pickle liquor for the synthesis of nZVI (S-nZVI), nZVI immobilised in mesoporous silica microspheres (SiO2@FeOOH@Fe) and nano Ni/Fe bimetallic particles (Ni/Fe) have been proved to show good property for elimination of polybrominated diphenyl ethers (PBDEs). However, it is necessary to compare their reactivity, reusability and stability when applied to in situ remediation. In this study, the performances of different iron-based nanoparticles were compared through reusability, sedimentation and iron dissolution experiments. The SiO2@FeOOH@Fe and Ni/Fe nanoparticles were shown to have higher reusability and stability, as they could be reused more than seven times, and that the SiO2@FeOOH@Fe can effectively avoid leaching iron ions into the solution and causing secondary pollution in the reaction. This study may serve as a reference for PBDE remediation in the future. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Pettit, C. D.; Barkhoudarian, S.; Daumann, A. G., Jr.; Provan, G. M.; ElFattah, Y. M.; Glover, D. E.
1999-01-01
In this study, we proposed an Advanced Health Management System (AHMS) functional architecture and conducted a technology assessment for liquid propellant rocket engine lifecycle health management. The purpose of the AHMS is to improve reusable rocket engine safety and to reduce between-flight maintenance. During the study, past and current reusable rocket engine health management-related projects were reviewed, data structures and health management processes of current rocket engine programs were assessed, and in-depth interviews with rocket engine lifecycle and system experts were conducted. A generic AHMS functional architecture, with primary focus on real-time health monitoring, was developed. Fourteen categories of technology tasks and development needs for implementation of the AHMS were identified, based on the functional architecture and our assessment of current rocket engine programs. Five key technology areas were recommended for immediate development, which (1) would provide immediate benefits to current engine programs, and (2) could be implemented with minimal impact on the current Space Shuttle Main Engine (SSME) and Reusable Launch Vehicle (RLV) engine controllers.
Addressing surface-induced loss and decoherence in superconducting quantum circuits
NASA Astrophysics Data System (ADS)
Fuhrer, Andreas; Mueller, Peter; Kuhlmann, Andreas; Filipp, Stefan; Deshpande, Veeresh; Drechsler, Ute
Many of the advances in coherence and fidelity of superconducting qubits have been made possible by clever engineering of the coupling to the environment and operation at noise-insensitive sweet spots. However, this leads to a compromise in experimental flexibility and device tunability, which can become inhibitive as the system size is scaled up. Material and interface related degrees of freedoms are harder to mitigate and are expected to become increasingly important in more complex systems. They impose limits both on coherence (flux-noise) and lifetimes (surface loss) of superconducting qubits. To study and eliminate these effects we have constructed a reusable UHV-compatible sample enclosure that enables us to perform various surface passivation steps before cooling superconducting devices to cryogenic temperatures. The enclosure can accommodate large chips with up to 18 microwave ports and can be vacuum sealed at pressures below 8e-10 mbar. We discuss its operation principle and present first measurement results of superconducting CPW resonators and qubit devices with and without prior surface treatments.
Thermal and aerothermal performance of a titanium multiwall thermal protection system
NASA Technical Reports Server (NTRS)
Avery, D. E.; Shideler, J. L.; Stuckey, R. N.
1981-01-01
A metallic thermal protection system (TPS) concept the multiwall designed for temperature and pressure at Shuttle body point 3140 where the maximum surface temperature is approximately 811 K was tested to evaluate thermal performance and structural integrity. A two tile model of titanium multiwall and a model consisting of a low temperature reusable surface insulation (LRSI) tiles were exposed to 25 simulated thermal and pressure Shuttle entry missions. The two systems performed the same, and neither system deteriorated during the tests. It is indicated that redesign of the multiwall tiles reduces tile thickness and/or weight. A nine tile model of titanium multiwal was tested for radiant heating and aerothermodynamics. Minor design changes that improve structural integrity without having a significant impact on the thermal protection ability of the titanium multiwall TPS are identified. The capability of a titanium multiwall thermal protection system to protect an aluminum surface during a Shuttle type entry trajectory at locations on the vehicle where the maximum surface temperature is below 811 K is demonstrated.
Optimization of Turbine Blade Design for Reusable Launch Vehicles
NASA Technical Reports Server (NTRS)
Shyy, Wei
1998-01-01
To facilitate design optimization of turbine blade shape for reusable launching vehicles, appropriate techniques need to be developed to process and estimate the characteristics of the design variables and the response of the output with respect to the variations of the design variables. The purpose of this report is to offer insight into developing appropriate techniques for supporting such design and optimization needs. Neural network and polynomial-based techniques are applied to process aerodynamic data obtained from computational simulations for flows around a two-dimensional airfoil and a generic three- dimensional wing/blade. For the two-dimensional airfoil, a two-layered radial-basis network is designed and trained. The performances of two different design functions for radial-basis networks, one based on the accuracy requirement, whereas the other one based on the limit on the network size. While the number of neurons needed to satisfactorily reproduce the information depends on the size of the data, the neural network technique is shown to be more accurate for large data set (up to 765 simulations have been used) than the polynomial-based response surface method. For the three-dimensional wing/blade case, smaller aerodynamic data sets (between 9 to 25 simulations) are considered, and both the neural network and the polynomial-based response surface techniques improve their performance as the data size increases. It is found while the relative performance of two different network types, a radial-basis network and a back-propagation network, depends on the number of input data, the number of iterations required for radial-basis network is less than that for the back-propagation network.
133Xe contamination found in internal bacteria filter of xenon ventilation system.
Hackett, Michael T; Collins, Judith A; Wierzbinski, Rebecca S
2003-09-01
We report on (133)Xe contamination found in the reusable internal bacteria filter of our xenon ventilation system. Internal bacteria filters (n = 6) were evaluated after approximately 1 mo of normal use. The ventilation system was evacuated twice to eliminate (133)Xe in the system before removal of the filter. Upon removal, the filter was monitored using a survey meter with an energy-compensated probe and was imaged on a scintillation camera. The filter was monitored and imaged over several days and was stored in a fume hood. Estimated (133)Xe activity in each filter immediately after removal ranged from 132 to 2,035 kBq (3.6-55.0 micro Ci), based on imaging. Initial surface radiation levels ranged from 0.4 to 4.5 micro Sv/h (0.04-0.45 mrem/h). The (133)Xe activity did not readily leave the filter over time (i.e., time to reach half the counts of the initial decay-corrected image ranged from <6 to >72 h). The majority of the image counts (approximately 70%) were seen in 2 distinctive areas in the filter. They corresponded to sites where the manufacturer used polyurethane adhesive to attach the fiberglass filter medium to the filter housing. (133)Xe contamination within the reusable internal bacteria filter of our ventilation system was easily detected by a survey meter and imaging. Although initial activities and surface radiation levels were low, radiation safety practices would dictate that a (133)Xe-contaminated bacteria filter be stored preferably in a fume hood until it cannot be distinguished from background before autoclaving or disposal.
Jabre, Patricia; Galinski, Michel; Ricard-Hibon, Agnes; Devaud, Marie Laure; Ruscev, Mirko; Kulstad, Erik; Vicaut, Eric; Adnet, Fréderic; Margenet, Alain; Marty, Jean; Combes, Xavier
2011-03-01
Emergency tracheal intubation is reported to be more difficult with single-use plastic than with reusable metal laryngoscope blades in both inhospital and out-of-hospital settings. Single-use metal blades have been developed but have not been compared with conventional metal blades. This controlled trial compares the efficacy and safety of single-use metal blades with reusable metal blades in out-of-hospital emergency tracheal intubation. This randomized controlled trial was carried out in France with out-of-hospital emergency medical units (Services de Médecine d'Urgence et de Réanimation). This was a multicenter prospective noninferiority randomized controlled trial in adult out-of-hospital patients requiring emergency tracheal intubation. Patients were randomly assigned to either single-use or reusable metal laryngoscope blades and intubated by a senior physician or a nurse anesthetist. The primary outcome was first-pass intubation success. Secondary outcomes were incidence of difficult intubation, need for alternate airway devices, and early intubation-related complications (esophageal intubation, mainstem intubation, vomiting, pulmonary aspiration, dental trauma, bronchospasm or laryngospasm, ventricular tachycardia, arterial desaturation, hypotension, or cardiac arrest). The study included 817 patients, including 409 intubated with single-use blades and 408 with a reusable blade. First-pass intubation success was similar in both groups: 292 (71.4%) for single-use blades, 290 (71.1%) for reusable blades. The 95% confidence interval (CI) for the difference in treatments (0.3%; 95% CI -5.9% to 6.5%) did not include the prespecified inferiority margin of -7%. There was no difference in rate of difficult intubation (difference 3%; 95% CI -7% to 2%), need for alternate airway (difference 4%; 95% CI -8% to 1%), or early complication rate (difference 3%; 95% CI -3% to 8%). First-pass out-of-hospital tracheal intubation success with single-use metal laryngoscopy blades was noninferior to first-pass success with reusable metal laryngoscope blades. Copyright © 2010 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.
A controlled experiment on the impact of software structure on maintainability
NASA Technical Reports Server (NTRS)
Rombach, Dieter H.
1987-01-01
The impact of software structure on maintainability aspects including comprehensibility, locality, modifiability, and reusability in a distributed system environment is studied in a controlled maintenance experiment involving six medium-size distributed software systems implemented in LADY (language for distributed systems) and six in an extended version of sequential PASCAL. For all maintenance aspects except reusability, the results were quantitatively given in terms of complexity metrics which could be automated. The results showed LADY to be better suited to the development of maintainable software than the extension of sequential PASCAL. The strong typing combined with high parametrization of units is suggested to improve the reusability of units in LADY.
Patwardhan, Anil
2010-01-01
The cut and sew Cox's maze III procedure is time-consuming. Therefore, various energy sources have been used for ablation, to replace the cut and sew technique. We have used the bipolar radiofrequency output of a standard electrosurgical generator with re-usable forceps for replicating the Cox's maze III procedure from August 1996. In addition, re-usable nitrous oxide based cryoprobe has been used at the atrioventricular valve annuli and on the coronary sinus. The 85.7% cure rate at one year compares with that for surgical ablation of atrial fibrillation using alternative energy sources.
A diagnostic approach to increase reusable dinnerware selection in a cafeteria.
Manuel, Jennifer C; Sunseri, Mary Anne; Olson, Ryan; Scolari, Miranda
2007-01-01
The current project tested a diagnostic approach to selecting interventions to increase patron selection of reusable dinnerware in a cafeteria. An assessment survey, completed by a sample of 43 patrons, suggested that the primary causes of wasteful behavior were (a) environmental arrangement of dinnerware options and (b) competing motivational variables. A functional relation between environmental arrangement and reusable product selection was demonstrated in a reversal design. However, the largest effect occurred as function of a multicomponent intervention involving environmental arrangement, employee involvement, and personal spoken prompts with motivational signs. The results support the use of informant assessments when designing community interventions.
Reusable rocket engine intelligent control system framework design, phase 2
NASA Technical Reports Server (NTRS)
Nemeth, ED; Anderson, Ron; Ols, Joe; Olsasky, Mark
1991-01-01
Elements of an advanced functional framework for reusable rocket engine propulsion system control are presented for the Space Shuttle Main Engine (SSME) demonstration case. Functional elements of the baseline functional framework are defined in detail. The SSME failure modes are evaluated and specific failure modes identified for inclusion in the advanced functional framework diagnostic system. Active control of the SSME start transient is investigated, leading to the identification of a promising approach to mitigating start transient excursions. Key elements of the functional framework are simulated and demonstration cases are provided. Finally, the advanced function framework for control of reusable rocket engines is presented.
A Diagnostic Approach to Increase Reusable Dinnerware Selection in a Cafeteria
Manuel, Jennifer C; Anne Sunseri, Mary; Olson, Ryan; Scolari, Miranda
2007-01-01
The current project tested a diagnostic approach to selecting interventions to increase patron selection of reusable dinnerware in a cafeteria. An assessment survey, completed by a sample of 43 patrons, suggested that the primary causes of wasteful behavior were (a) environmental arrangement of dinnerware options and (b) competing motivational variables. A functional relation between environmental arrangement and reusable product selection was demonstrated in a reversal design. However, the largest effect occurred as function of a multicomponent intervention involving environmental arrangement, employee involvement, and personal spoken prompts with motivational signs. The results support the use of informant assessments when designing community interventions. PMID:17624069
NASA Technical Reports Server (NTRS)
Borsody, J.
1976-01-01
Equations are derived by using the maximum principle to maximize the payload of a reusable tug for planetary missions. The analysis includes a correction for precession of the space shuttle orbit. The tug returns to this precessed orbit (within a specified time) and makes the required nodal correction. A sample case is analyzed that represents an inner planet mission as specified by a fixed declination and right ascension of the outgoing asymptote and the mission energy. The reusable stage performance corresponds to that of a typical cryogenic tug. Effects of space shuttle orbital inclination, several trajectory parameters, and tug thrust on payload are also investigated.
Review of X-33 Hypersonic Aerodynamic and Aerothermodynamic Development
2000-09-01
proposed development of a fully reusable, rocket pow- ered, single-stage-to-orbit ( SSTO ) vehicle capa- ble of delivering 25,000 lbs (including crew...space at greatly reduced cost. The “Access-to-Space” study identified critical technologies that required development before a SSTO reusable launch
Design data book phase A/B study for a pressure fed engine on a reusable space shuttle booster
NASA Technical Reports Server (NTRS)
1972-01-01
Preliminary engineering definition information is presented for a liquid pressure-fed reusable booster engine. The material is reported in three separate sections which include: (1) program and baseline data, (2) critical trade studies summary, and (3) methodology.
Microbiological contamination in high and low flow oxygen humidifiers: A systematic review.
de la Fuente-Sancho, I; Romeu-Bordas, Ó; Fernández-Aedo, I; Vallejo De la Hoz, G; Ballesteros-Peña, S
2017-12-16
To determine the risk of microbiological contamination with hospital use high- and low-flow bubbling humidifiers. A systematic literature review was carried out in 6 databases. Observational or experimental studies published between 1990 and 2016 were selected, written in English or Spanish, and in which microbiological contamination with hospital use high- and low-flow bubbling humidifiers was investigated. A total of 12 articles were included: 4 analyzed the water from reusable humidifiers, 4 analyzed the water from prefilled system humidifiers, and the rest compared samples from both models. Microbial contamination was observed in all studies in which reusable humidifiers were evaluated, usually involving common bacteria from the skin flora, while potential pathogenic species were notified in 2 studies. No microbial contamination was isolated from reusable humidifiers, regardless of whether they had been consecutively used over time by a single patient or by several patients. On one hand, there seems to be a low risk of contamination during the first weeks of use of prefilled humidifiers, which allows multiple use in different patients, without a risk of cross-contamination. On the other hand, it should be underscored that handling reusable humidifiers without correct aseptic measures can increase the risk of contamination; replacing reusable humidifiers with prefilled models therefore could be the safest option. Copyright © 2017. Publicado por Elsevier España, S.L.U.
Systematic review of reusable versus disposable laparoscopic instruments: costs and safety.
Siu, Joey; Hill, Andrew G; MacCormick, Andrew D
2017-01-01
The quality of instruments and surgical expertise in minimally invasive surgery has developed markedly in the last two decades. Attention is now being turned to ways to allow surgeons to adopt more cost-effective and environmental-friendly approaches. This review explores current evidence on the cost and environmental impact of reusable versus single-use instruments. In addition, we aim to compare their quality, functionality and associated clinical outcomes. The Medline and EMBASE databases were searched for relevant literature from January 2000 to May 2015. Subject headings were Equipment Reuse/, Disposable Equipment/, Cholecystectomy/, Laparoscopic/, Laparoscopy/, Surgical Instruments/, Medical Waste Disposal/, Waste Management/, Medical Waste/, Environmental Sustainability/ and Sterilization/. There are few objective comparative analyses between single-use versus reusable instruments. Current evidence suggests that limiting use of disposal instruments to necessity may hold both economical and environmental advantages. Theoretical advantages of single-use instruments in quality, safety, sterility, ease of use and importantly patient outcomes have rarely been examined. Cost-saving methods, environmental-friendly methods, global operative costs, hidden costs, sterilization methods and quality assurance systems vary greatly between studies making it difficult to gain an overview of the comparison between single-use and reusable instruments. Further examination of cost comparisons between disposable and reusable instruments is necessary while externalized environmental costs, instrument function and safety are also important to consider in future studies. © 2016 Royal Australasian College of Surgeons.
NASA Technical Reports Server (NTRS)
Gallegos, J. J.
1978-01-01
A multi-objective test program was conducted at the NASA/JSC Radiant Heat Test Facility in which an aluminum skin/stringer test panel insulated with FRSI (Flexible Reusable Surface Insulation) was subjected to 24 simulated Space Shuttle Orbiter ascent/entry heating cycles with a cold soak in between in the 10th and 20th cycles. A two-dimensional thermal math model was developed and utilized to predict the thermal performance of the FRSI. Results are presented which indicate that the modeling techniques and property values have been proven adequate in predicting peak structure temperatures and entry thermal responses from both an ambient and cold soak condition of an FRSI covered aluminum structure.
Project Morpheus: Morpheus 1.5A Lander Failure Investigation Results
NASA Technical Reports Server (NTRS)
Devolites, Jennifer L.; Olansen, Jon B.; Munday, Stephen R.
2013-01-01
On August 9, 2012 the Morpheus 1.5A vehicle crashed shortly after lift off from the Kennedy Space Center. The loss was limited to the vehicle itself which was pre-declared to be a test failure and not a mishap. The Morpheus project is demonstrating advanced technologies for in space and planetary surface vehicles including: autonomous flight control, landing site hazard identification and safe site selection, relative surface and hazard navigation, precision landing, modular reusable flight software, and high performance, non-toxic, cryogenic liquid Oxygen and liquid Methane integrated main engine and attitude control propulsion system. A comprehensive failure investigation isolated the fault to the Inertial Measurement Unit (IMU) data path to the flight computer. Several improvements have been identified and implemented for the 1.5B and 1.5C vehicles.
Cultivation of animal cells in a reticulated vitreous carbon foam.
Kent, B L; Mutharasan, R
1992-02-01
A reticulated vitreous carbon foam (RVCF) was used as a surface to cultivate a model anchorage-dependent animal cell line, 3T6 (mouse embryo fibroblast). This fixed-surface bioreactor provided a low-shear, chemically-inert, and reusable environment for cell growth. An external medium recirculation loop allowed aeration, nutrient monitoring, and medium replacement without disturbing the cells. Optimal flow rates for the attachment and growth phases were determined. Growth rates comparable to static (T-flask and petri dish) cultures and agitated microcarrier cultures were achieved with appropriately high medium recirculation rates. Metabolic parameters were shown to be useful indicators of cell mass, although specific glucose consumption rates were considerably higher for cultures in the RVCF reactor. Oxygen supply was shown to be the most likely limiting factor for scaleup.
FEEDBACK SCORING SYSTEMS FOR REUSABLE KINDERGARTEN WORKBOOKS.
ERIC Educational Resources Information Center
GACH, PENELOPE J.; AND OTHERS
THE DEVELOPMENT OF ECONOMICAL FEEDBACK SCORING SYSTEMS FOR REUSABLE KINDERGARTEN WORKBOOKS IS DESCRIBED. THREE PROTOTYPE SYSTEMS WERE DEVELOPED--(1) A METAL FOIL ACTIVATING AN ELECTRICAL PROBE, (2) A METAL FOIL REACTING WITH A MAGNETIC PROBE, AND (3) INVISIBLE FLUORESCENT INK REVEALED BY THE APPLICATION OF LONGWAVE ULTRAVIOLET LIGHT. (MS)
14 CFR 431.35 - Acceptable reusable launch vehicle mission risk.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Acceptable reusable launch vehicle mission risk. 431.35 Section 431.35 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION... launch flight through orbital insertion of an RLV or vehicle stage or flight to outer space, whichever is...
14 CFR 431.35 - Acceptable reusable launch vehicle mission risk.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Acceptable reusable launch vehicle mission risk. 431.35 Section 431.35 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION... launch flight through orbital insertion of an RLV or vehicle stage or flight to outer space, whichever is...
14 CFR 431.35 - Acceptable reusable launch vehicle mission risk.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Acceptable reusable launch vehicle mission risk. 431.35 Section 431.35 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION... launch flight through orbital insertion of an RLV or vehicle stage or flight to outer space, whichever is...
14 CFR 431.35 - Acceptable reusable launch vehicle mission risk.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Acceptable reusable launch vehicle mission risk. 431.35 Section 431.35 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION... launch flight through orbital insertion of an RLV or vehicle stage or flight to outer space, whichever is...
14 CFR 431.33 - Safety organization.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Safety organization. 431.33 Section 431.33... TRANSPORTATION LICENSING LAUNCH AND REENTRY OF A REUSABLE LAUNCH VEHICLE (RLV) Safety Review and Approval for Launch and Reentry of a Reusable Launch Vehicle § 431.33 Safety organization. (a) An applicant shall...
2009-07-01
Breaks in the internal wires of reusable electrosurgical active electrode cables can increase the risk of injuries and surgical fires. Careful visual and manual inspection during reprocessing and immediately before use, coupled with periodic replacement, can help limit the risk.
14 CFR 420.19 - Launch site location review-general.
Code of Federal Regulations, 2010 CFR
2010-01-01
... site, at least one type of expendable or reusable launch vehicle can be flown from the launch point... × 10−6). (2) Types of launch vehicles include orbital expendable launch vehicles, guided sub-orbital expendable launch vehicles, unguided sub-orbital expendable launch vehicles, and reusable launch vehicles...
Reusable Launch Vehicle (RLV) Mission/Market Model
NASA Technical Reports Server (NTRS)
Prince, Frank A.
1999-01-01
The goal of this model was to assess the Reusable Launch Vehicle's (RLV) capability to support the International Space Station (ISS) servicing, determine the potential to leverage the commercial marketplace to reduce NASA's cost, and to evaluate the RLV's ability to expand the space economy. The presentation is in view-graph format.
Mobile Authoring of Open Educational Resources as Reusable Learning Objects
ERIC Educational Resources Information Center
Kinshuk; Jesse, Ryan
2013-01-01
E-learning technologies have allowed authoring and playback of standardized reusable learning objects (RLO) for several years. Effective mobile learning requires similar functionality at both design time and runtime. Mobile devices can play RLO using applications like SMILE, mobile access to a learning management system (LMS), or other systems…
14 CFR 431.35 - Acceptable reusable launch vehicle mission risk.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Acceptable reusable launch vehicle mission risk. 431.35 Section 431.35 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION... launch flight through orbital insertion of an RLV or vehicle stage or flight to outer space, whichever is...
Learning Objects, Repositories, Sharing and Reusability
ERIC Educational Resources Information Center
Koppi, Tony; Bogle, Lisa; Bogle, Mike
2005-01-01
The online Learning Resource Catalogue (LRC) Project has been part of an international consortium for several years and currently includes 25 institutions worldwide. The LRC Project has evolved for several pragmatic reasons into an academic network whereby members can identify and share reusable learning objects as well as collaborate in a number…
Experiences with Reusable E-Learning Objects: From Theory to Practice.
ERIC Educational Resources Information Center
Muzio, Jeanette A.; Heins, Tanya; Mundell, Roger
2002-01-01
Explains reusable electronic learning objects (ELOs) that are stored in a database and discusses the practical application of creating and reusing ELOs at Royal Roads University (Canada). Highlights include ELOs and the instructional design of online courses; and examples of using templates to develop interactive ELOs. (Author/LRW)
Assessment of the Feasibility of Innovative Reusable Launchers
NASA Astrophysics Data System (ADS)
Chiesa, S.; Corpino, S.; Viola, N.
The demand for getting access to space, in particular to Low Earth Orbit, is increasing and fully reusable launch vehicles (RLVs) are likely to play a key role in the development of future space activities. Up until now this kind of space systems has not been successfully carried out: in fact today only the Space Shuttle, which belongs to the old generation of launchers, is operative and furthermore it is not a fully reusable system. In the nineties many studies regarding advanced transatmospheric planes were started, but no one was accomplished because of the technological problems encountered and the high financial resources required with the corresponding industrial risk. One of the most promising project was the Lockheed Venture Star, which seemed to have serious chances to be carried out. Anyway, if this ever happens, it will take quite a long time thus the operative life of Space Shuttle will have to be extended for the International Space Station support. The purpose of the present work is to assess the feasibility of different kinds of advanced reusable launch vehicles to gain access to space and to meet the requirements of today space flight needs, which are mainly safety and affordability. Single stage to orbit (SSTO), two stage to orbit (TSTO) and the so called "one and a half" stage to orbit vehicles are here taken into account to highlight their advantages and disadvantages. The "one and a half" stage to orbit vehicle takes off and climbs to meet a tanker aircraft to be aerially refuelled and then, after disconnecting from the tanker, it flies to reach the orbit. In this case, apart from the space vehicle, also the tanker aircraft needs a dedicated study to examine the problems related to the refuelling at high subsonic speeds and at a height near the tropopause. Only winged vehicles which take off and land horizontally are considered but different architectural layouts and propulsive configurations are hypothesised. Unlike the Venture Star, which takes off like the Space Shuttle, this kind of reusable launch vehicles, called spaceplanes, should all be able to be maintained and operated from airports, thus making the launch and recovery phases easier and more affordable. Apart from being an innovative attempt to get access to space, spaceplanes look likely to revolutionize long distance plane travel, with travel times between any two cities connecting USA, Europe, Japan and Australia being only a few hours. SSTO winged vehicles may be at the margins of feasibility as a reusable SSTO design attempts to take two major steps at once: step one being a fully reusable vehicle and step two being a single-stage reusable vehicle. It is well known that the accomplishment of the SSTO vehicle requires a dramatic effort from the technological point of view even though the integration design appears to be quite easy. If compared to the SSTO, the TSTO reusable vehicle is less technically demanding as, for example, state-of-the-art engines can be used but the integration design is surely more complex. An optimum solution may be represented by the "one and a half" stage to orbit vehicle. In fact getting the "one and a half" reusable vehicle into orbit doesn't look impossible but it surely does look challenging. In this paper the study of the feasibility and the technological assessment of new space systems concepts are accomplished by: The work we are involved in is still under way but the first results we have had are encouraging.
Saleem, Mahmood; Khan, Rafi Ullah; Tahir, M. Suleman; Krammer, Gernot
2011-01-01
Pulse-jet bag filters are frequently employed for particle removal from off gases. Separated solids form a layer on the permeable filter media called filter cake. The cake is responsible for increasing pressure drop. Therefore, the cake has to be detached at a predefined upper pressure drop limit or at predefined time intervals. Thus the process is intrinsically semi-continuous. The cake formation and cake detachment are interdependent and may influence the performance of the filter. Therefore, understanding formation and detachment of filter cake is important. In this regard, the filter media is the key component in the system. Needle felts are the most commonly used media in bag filters. Cake formation studies with heat treated and membrane coated needle felts in pilot scale pulse jet bag filter were carried out. The data is processed according to the procedures that were published already [Powder Technology, Volume 173, Issue 2, 19 April 2007, Pages 93–106]. Pressure drop evolution, cake height distribution evolution, cake patches area distribution and their characterization using fractal analysis on different needle felts are presented here. It is observed that concavity of pressure drop curve for membrane coated needle felt is principally caused by presence of inhomogeneous cake area load whereas it is inherent for heat treated media. Presence of residual cake enhances the concavity of pressure drop at the start of filtration cycle. Patchy cleaning is observed only when jet pulse pressure is too low and unable to provide the necessary force to detach the cake. The border line is very sharp. Based on experiments with limestone dust and three types of needle felts, for the jet pulse pressure above 4 bar and filtration velocity below 50 mm/s, cake is detached completely except a thin residual layer (100–200 μm). Uniformity and smoothness of residual cake depends on the surface characteristics of the filter media. Cake height distribution of residual cake and newly formed cake during filtration prevails. The patch size analysis and fractal analysis reveal that residual cake grow in size (latterly) following regeneration initially on the base with edges smearing out, however, the cake heights are not leveled off. Fractal dimension of cake patches boundary falls in the range of 1–1.4 and depends on vertical position as well as time of filtration. Cake height measurements with Polyimide (PI) needle felts were hampered on account of its photosensitive nature. PMID:24415801
Issues Related to Cleaning Complex Geometry Surfaces with ODC-Free Solvents
NASA Technical Reports Server (NTRS)
Bradford, Blake F.; Wurth, Laura A.; Nayate, Pramod D.; McCool, Alex (Technical Monitor)
2001-01-01
Implementing ozone depleting chemicals (ODC)-free solvents into full-scale reusable solid rocket motor cleaning operations has presented problems due to the low vapor pressures of the solvents. Because of slow evaporation, solvent retention is a problem on porous substrates or on surfaces with irregular geometry, such as threaded boltholes, leak check ports, and nozzle backfill joints. The new solvents are being evaluated to replace 1,1,1-trichloroethane, which readily evaporates from these surfaces. Selection of the solvents to be evaluated on full-scale hardware was made based on results of subscale tests performed with flat surface coupons, which did not manifest the problem. Test efforts have been undertaken to address concerns with the slow-evaporating solvents. These concerns include effects on materials due to long-term exposure to solvent, potential migration from bolthole threads to seal surfaces, and effects on bolt loading due to solvent retention in threads. Tests performed to date have verified that retained solvent does not affect materials or hardware performance. Process modifications have also been developed to assist drying, and these can be implemented if additional drying becomes necessary.
Dynamics of spider glue adhesion: effect of surface energy and contact area
NASA Astrophysics Data System (ADS)
Amarpuri, Gaurav; Chen, Yizhou; Blackledge, Todd; Dhinojwala, Ali
Spider glue is a unique biological adhesive which is humidity responsive such that the adhesion continues to increase upto 100% relative humidity (RH) for some species. This is unlike synthetic adhesives that significantly drop in adhesion with an increase in humidity. However, most of adhesion data reported in literature have used clean hydrophilic glass substrate, unlike the hydrophobic, and charged insect cuticle surface that adheres to spider glue in nature. Previously, we have reported that the spider glue viscosity changes over five orders of magnitude with humidity. Here, we vary the surface energy and surface charge of the substrate to test the change in Larnioides cornutus spider glue adhesion with humidity. We find that an increase in both surface energy and surface charge density increases the droplet spreading and there exists an optimum droplet contact area where adhesion is maximized. Moreover, spider glue droplets act as reusable adhesive for low energy hydrophobic surface at the optimum humidity. These results explain why certain prey are caught more efficiently by spiders in their habitat. The mechanism by which spider species tune its glue adhesion for local prey capture can inspire new generation smart adhesives.
Ablative heat shield design for space shuttle
NASA Technical Reports Server (NTRS)
Seiferth, R. W.
1973-01-01
Ablator heat shield configuration optimization studies were conducted for the orbiter. Ablator and reusable surface insulation (RSI) trajectories for design studies were shaped to take advantage of the low conductance of ceramic RSI and high temperature capability of ablators. Comparative weights were established for the RSI system and for direct bond and mechanically attached ablator systems. Ablator system costs were determined for fabrication, installation and refurbishment. Cost penalties were assigned for payload weight penalties, if any. The direct bond ablator is lowest in weight and cost. A mechanically attached ablator using a magnesium subpanel is highly competitive for both weight and cost.
High pressure water jet cutting and stripping
NASA Technical Reports Server (NTRS)
Hoppe, David T.; Babai, Majid K.
1991-01-01
High pressure water cutting techniques have a wide range of applications to the American space effort. Hydroblasting techniques are commonly used during the refurbishment of the reusable solid rocket motors. The process can be controlled to strip a thermal protective ablator without incurring any damage to the painted surface underneath by using a variation of possible parameters. Hydroblasting is a technique which is easily automated. Automation removes personnel from the hostile environment of the high pressure water. Computer controlled robots can perform the same task in a fraction of the time that would be required by manual operation.
Close up detail of the underside of the Orbiter Discovery ...
Close up detail of the underside of the Orbiter Discovery in the Vehicle Assembly Building at NASA's Kennedy Space Center. This view is from underneath the aft section looking forward. It is a close-up view of the High-temperature Reusable Surface Insulation tiles showing the wear patterns from the heat of reentry, consequential replacement of worn and damaged tiles. The wear and replacement patters are unique to each Orbiter which can serve as their particular "fingerprint". - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX