Sample records for vacuum microgravity furnace

  1. Furnace brazing under partial vacuum (United States)

    Mckown, R. D.


    Brazing furnace utilizing partial-vacuum technique reduces tooling requirements and produces better bond. Benefit in that partial vacuum helps to dissociate metal oxides that inhibit metal flow and eliminates heavy tooling required to hold parts together during brazing.

  2. Effect of electropolishing on vacuum furnace design

    Directory of Open Access Journals (Sweden)

    Sutanwi Lahiri


    Full Text Available The use of thermal shields of materials having low emissivity in vacuum furnaces is well-known. However, the surface condition of the heat shields is one of the most important factors governing their efficiency as radiation resistances. The emissivity of the thermal shields dictates the power rating of the heaters in furnace design. The unpolished materials used in the heater tests showed poor performance leading to loss of a signi­ficant percentage of the input power. The present work deals with the refur­bishment of the radiation heat shields used in a furnace for heating graphite structure. The effect of refurbishment of the heat shields by the buffing and subsequently electro­polishing was found to improve the performance of the shields as heat reflectors. The com­position of the electrolyte was chosen in such a way that the large shields of Mo, Inconel and SS can be polished using the same reagents in different ratios. The present work deals with the development of a standard electropolishing procedure for large metallic sheets and subsequently qualifying them by roughness and emissivity measure­ments. The improvement noted in the shielding efficiency of the furnace in the subsequent runs is also discussed here.

  3. Improved Blackbody Temperature Sensors for a Vacuum Furnace (United States)

    Farmer, Jeff; Coppens, Chris; O'Dell, J. Scott; McKechnie, Timothy N.; Schofield, Elizabeth


    Some improvements have been made in the design and fabrication of blackbody sensors (BBSs) used to measure the temperature of a heater core in a vacuum furnace. Each BBS consists of a ring of thermally conductive, high-melting-temperature material with two tantalum-sheathed thermocouples attached at diametrically opposite points. The name "blackbody sensor" reflects the basic principle of operation. Heat is transferred between the ring and the furnace heater core primarily by blackbody radiation, heat is conducted through the ring to the thermocouples, and the temperature of the ring (and, hence, the temperature of the heater core) is measured by use of the thermocouples. Two main requirements have guided the development of these BBSs: (1) The rings should have as high an emissivity as possible in order to maximize the heat-transfer rate and thereby maximize temperature-monitoring performance and (2) the thermocouples must be joined to the rings in such a way as to ensure long-term, reliable intimate thermal contact. The problem of fabricating a BBS to satisfy these requirements is complicated by an application-specific prohibition against overheating and thereby damaging nearby instrumentation leads through the use of conventional furnace brazing or any other technique that involves heating the entire BBS and its surroundings. The problem is further complicated by another application-specific prohibition against damaging the thin tantalum thermocouple sheaths through the use of conventional welding to join the thermocouples to the ring. The first BBS rings were made of graphite. The tantalum-sheathed thermocouples were attached to the graphite rings by use of high-temperature graphite cements. The ring/thermocouple bonds thus formed were found to be weak and unreliable, and so graphite rings and graphite cements were abandoned. Now, each BBS ring is made from one of two materials: either tantalum or a molybdenum/titanium/zirconium alloy. The tantalum

  4. Flexible Transfer of Regolith in Micro-Gravity and Vacuum Project (United States)

    National Aeronautics and Space Administration — A novel, robust method of collection and transfer of NEO/Phobos material under micro-gravity conditions under vacuum/space environment with minimal loss of volatiles...

  5. Ultra-high vacuum compatible induction-heated rod casting furnace


    Bauer, Andreas; Neubauer, Andreas; Münzer, Wolfgang; Regnat, Alexander; Benka, Georg; Meven, Martin; Pedersen, Björn; Pfleiderer, Christian


    We report the design of a radio-frequency induction-heated rod casting furnace that permits the preparation of polycrystalline ingots of intermetallic compounds under ultra-high vacuum compatible conditions. The central part of the system is a bespoke water-cooled Hukin crucible supporting a casting mold. Depending on the choice of the mold, typical rods have a diameter between 6 mm and 10 mm and a length up to 90 mm, suitable for single-crystal growth by means of float-zoning. The setup is a...

  6. Ultra-high vacuum compatible induction-heated rod casting furnace (United States)

    Bauer, A.; Neubauer, A.; Münzer, W.; Regnat, A.; Benka, G.; Meven, M.; Pedersen, B.; Pfleiderer, C.


    We report the design of a radio-frequency induction-heated rod casting furnace that permits the preparation of polycrystalline ingots of intermetallic compounds under ultra-high vacuum compatible conditions. The central part of the system is a bespoke water-cooled Hukin crucible supporting a casting mold. Depending on the choice of the mold, typical rods have a diameter between 6 mm and 10 mm and a length up to 90 mm, suitable for single-crystal growth by means of float-zoning. The setup is all-metal sealed and may be baked out. We find that the resulting ultra-high vacuum represents an important precondition for processing compounds with high vapor pressures under a high-purity argon atmosphere up to 3 bars. Using the rod casting furnace, we succeeded to prepare large high-quality single crystals of two half-Heusler compounds, namely, the itinerant antiferromagnet CuMnSb and the half-metallic ferromagnet NiMnSb.

  7. The development of two new KC-135 furnaces for studies on microgravity materials processing (United States)

    Fiske, Michael; Cockburn, James; Poorman, Richard


    Wyle Laboratories is currently designing and fabricating two KC-135 materials processing furnaces for Marshall Space Flight Center. The first of these, called the Rapid Melt/Rapid Quench (RM/RQ) Furnace, will be used to melt and resolidify Cu-, Al-, and Ni-based alloys and composites, all during the 20 to 30 seconds of low gravity (0.1 to 0.001 g) available in a single parabola of the KC-135. In addition, it will be capable of directional solidification of these alloys. The furnace can be configured for either liquid or gas quenching of the samples. The second furnace, called the Polymer Solidification Transparent (PST) Furnace, will use a wide range of sample translation rates to directionally solidify polymers and low-melting-point metals as the KC-135 flies a series of parabolic maneuvers. The use of transparent crucibles and an optics system between the hot and cold zones of the furnace will allow for high-resolution video monitoring of the solid-liquid interface during processing. It is hoped that the development of these two furnaces will lead to significant increases in understanding of interface kinetics, fluid flow, and heat transfer in materials during solidification in a low-gravity environment.

  8. Equipment concept design and development plans for microgravity science and applications research on space station: Combustion tunnel, laser diagnostic system, advanced modular furnace, integrated electronics laboratory (United States)

    Uhran, M. L.; Youngblood, W. W.; Georgekutty, T.; Fiske, M. R.; Wear, W. O.


    Taking advantage of the microgravity environment of space NASA has initiated the preliminary design of a permanently manned space station that will support technological advances in process science and stimulate the development of new and improved materials having applications across the commercial spectrum. Previous studies have been performed to define from the researcher's perspective, the requirements for laboratory equipment to accommodate microgravity experiments on the space station. Functional requirements for the identified experimental apparatus and support equipment were determined. From these hardware requirements, several items were selected for concept designs and subsequent formulation of development plans. This report documents the concept designs and development plans for two items of experiment apparatus - the Combustion Tunnel and the Advanced Modular Furnace, and two items of support equipment the Laser Diagnostic System and the Integrated Electronics Laboratory. For each concept design, key technology developments were identified that are required to enable or enhance the development of the respective hardware.

  9. Brazing open cell reticulated copper foam to stainless steel tubing with vacuum furnace brazed gold/indium alloy plating (United States)

    Howard, Stanley R [Windsor, SC; Korinko, Paul S [Aiken, SC


    A method of fabricating a heat exchanger includes brush electroplating plated layers for a brazing alloy onto a stainless steel tube in thin layers, over a nickel strike having a 1.3 .mu.m thickness. The resultant Au-18 In composition may be applied as a first layer of indium, 1.47 .mu.m thick, and a second layer of gold, 2.54 .mu.m thick. The order of plating helps control brazing erosion. Excessive amounts of brazing material are avoided by controlling the electroplating process. The reticulated copper foam rings are interference fit to the stainless steel tube, and in contact with the plated layers. The copper foam rings, the plated layers for brazing alloy, and the stainless steel tube are heated and cooled in a vacuum furnace at controlled rates, forming a bond of the copper foam rings to the stainless steel tube that improves heat transfer between the tube and the copper foam.

  10. Annealing effect on the particle size and chemical composition of activated carbon obtained from vacuum furnace of teak sawdust

    Energy Technology Data Exchange (ETDEWEB)

    Armynah, B., E-mail:; Tahir, D., E-mail:; Jaya, N., E-mail: [Department of Physics, Hasanuddin University, Makassar 90245 (Indonesia)


    Activated carbon was produced from sawdust by using physical method in a high temperature vacuum furnace without additional chemical. Fast pyrolysis process was carried out prior in fluidized a bed furnace to produce char before activation process. Experiments were conducted to investigate the influence of various process parameters such as particle size, activation temperature and activation time on the quality of the activated carbon. In addition, the chemical composition studies were done by using x-ray fluorescence (XRF) spectroscopy. The crystallite sizes were calculated by using Scherer equation based on x-ray diffraction (XRD) spectroscopy data. The pyrolysis temperature and time were varied from 600°C to 900°C and from 3 hours to 6 hours, respectively. The particle size of activated carbon was increase with increasing temperature. The composition and crystallite size of the prepared activated carbon was compared with the non-activated carbon. The results indicated that the teak sawdust carbon could be employed as a low cost alternative to produce commercial activated carbon.

  11. Ceramic material suitable for repair of a space vehicle component in a microgravity and vacuum environment, method of making same, and method of repairing a space vehicle component (United States)

    Riedell, James A. (Inventor); Easler, Timothy E. (Inventor)


    A precursor of a ceramic adhesive suitable for use in a vacuum, thermal, and microgravity environment. The precursor of the ceramic adhesive includes a silicon-based, preceramic polymer and at least one ceramic powder selected from the group consisting of aluminum oxide, aluminum nitride, boron carbide, boron oxide, boron nitride, hafnium boride, hafnium carbide, hafnium oxide, lithium aluminate, molybdenum silicide, niobium carbide, niobium nitride, silicon boride, silicon carbide, silicon oxide, silicon nitride, tin oxide, tantalum boride, tantalum carbide, tantalum oxide, tantalum nitride, titanium boride, titanium carbide, titanium oxide, titanium nitride, yttrium oxide, zirconium diboride, zirconium carbide, zirconium oxide, and zirconium silicate. Methods of forming the ceramic adhesive and of repairing a substrate in a vacuum and microgravity environment are also disclosed, as is a substrate repaired with the ceramic adhesive.

  12. Protecting brazing furnaces from air leaks (United States)

    Armenoff, C. T.; Mckown, R. D.


    Inexpensive inert-atmosphere shielding protects vacuum brazing-furnace components that are likely to spring leak. Pipefittings, gages, and valves are encased in transparent plastic shroud inflated with argon. If leak develops, harmless argon will enter vacuum chamber, making it possible to finish ongoing brazing or heat treatment before shutting down for repair.

  13. CASTING FURNACES (United States)

    Ruppel, R.H.; Winters, C.E.


    A device is described for casting uranium which comprises a crucible, a rotatable table holding a plurality of molds, and a shell around both the crucible and the table. The bottom of the crucible has an eccentrically arranged pouring hole aligned with one of the molds at a time. The shell can be connected with a vacuum.

  14. Heat treatment furnace

    Energy Technology Data Exchange (ETDEWEB)

    Seals, Roland D; Parrott, Jeffrey G; DeMint, Paul D; Finney, Kevin R; Blue, Charles T


    A furnace heats through both infrared radiation and convective air utilizing an infrared/purge gas design that enables improved temperature control to enable more uniform treatment of workpieces. The furnace utilizes lamps, the electrical end connections of which are located in an enclosure outside the furnace chamber, with the lamps extending into the furnace chamber through openings in the wall of the chamber. The enclosure is purged with gas, which gas flows from the enclosure into the furnace chamber via the openings in the wall of the chamber so that the gas flows above and around the lamps and is heated to form a convective mechanism in heating parts.

  15. Dental Porcelain Furnaces: Test and Evaluation. (United States)


    Due to the low cost of this unit it should be considered for any laboratory with a moderate to high metal-ceramic fixed partial denture work load. New...either with or without vacuum. * Slow cooling cycle: This feature allows the units to be removed slowly from the muffle following the firing cycle...DEGREES HIGH TEMPERATURE 940 DEGREES TEMPERATURE RATE 55 DEG/MIN TIME AT TEMP 0.0 MINUTES REMOVAL TIME 0.3 MINUTES FURNACE TEMP 497 DEGREES CHAMBER VACUUM

  16. Preparation for microgravity - The role of the Microgravity Material Science Laboratory (United States)

    Johnston, J. Christopher; Rosenthal, Bruce N.; Meyer, Maryjo B.; Glasgow, Thomas K.


    Experiments at the NASA Lewis Research Center's Microgravity Material Science Laboratory using physical and mathematical models to delineate the effects of gravity on processes of scientific and commercial interest are discussed. Where possible, transparent model systems are used to visually track convection, settling, crystal growth, phase separation, agglomeration, vapor transport, diffusive flow, and polymer reactions. Materials studied include metals, alloys, salts, glasses, ceramics, and polymers. Specific technologies discussed include the General Purpose furnace used in the study of metals and crystal growth, the isothermal dendrite growth apparatus, the electromagnetic levitator/instrumented drop tube, the high temperature directional solidification furnace, the ceramics and polymer laboratories and the center's computing facilities.

  17. Calculations in furnace technology

    CERN Document Server

    Davies, Clive; Hopkins, DW; Owen, WS


    Calculations in Furnace Technology presents the theoretical and practical aspects of furnace technology. This book provides information pertinent to the development, application, and efficiency of furnace technology. Organized into eight chapters, this book begins with an overview of the exothermic reactions that occur when carbon, hydrogen, and sulfur are burned to release the energy available in the fuel. This text then evaluates the efficiencies to measure the quantity of fuel used, of flue gases leaving the plant, of air entering, and the heat lost to the surroundings. Other chapters consi

  18. Measurement of diffusion coefficient of liquid metals by using Gradient Heating Furnace in ISS


    Masaki, Tadahiko; Itami, Toshio; Watanabe, Yuki; 正木 匡彦; 伊丹 俊夫; 渡辺 勇基


    The experimental techniques for the measurements of diffusion coefficient have been studied in JAXA toward the utilization of microgravity environment in ISS (International Space Station). The experimental cartridge for the gradient heating furnace, GHF (Gradient Heating Furnace), was developed for the application of shear cell which is the advanced technique of diffusion experiments. The temperature profiles of GHF were measured for the diffusion experiments and the isothermal condition can ...

  19. Carbothermal reduction process of silica formed from shirasu volcanic ash using solar furnace

    Directory of Open Access Journals (Sweden)

    Hatakeyama Keisuke


    Full Text Available Metallurgical grade silicon was formed using Shirasu volcanic ash as starting material with solar furnace. The solar furnace was composed of two parts: Fresnel lens and reacting furnace. The reacting furnace was composed of a cylindrical vacuum chamber and quartz glass plate functioning to guide the concentrated sunlight into the furnace, and was placed at the focal point of the Fresnel lens. The sample was made from a mixture of silica formed from Shirasu volcanic ash and carbon, and placed in the carbon crucible inside the reacting furnace. The sample was irradiated for 3 hours, and the furnace was left until it cooled down to room temperature. After the cooling process, the sample was mixed and placed in the carbon crucible, and it was irradiated and cooled with the same processes again. After the experiment, the sample was evaluated by X-ray diffraction and the production of silicon was confirmed.

  20. Single crystal fibers growth of double lithium, lanthanium molybdate and adjustment of a micro-pulling down furnace for high vacuum setup; Crescimento de fibras de molibdato duplo de litio e lantanio e adaptacao de sistema de alto vacuo para micro pulling-down

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Fernando Rodrigues da


    In this work we investigated crystal growth procedures aiming the development of single crystal fiber (SCF) for laser applications. For quality optimization in the fabrication of fluorides SCF a new growth chamber for a micro-pulling down furnace ({mu}-PD) was constructed targeting the fibers fabrication with strict atmosphere control (high vacuum, gas flux and static atmospheres). Simultaneously, the SCF growth process of rare earth double molybdates was studied. The growth of pure and Nd{sup 3+}-doped SCF of LiLa(MoO{sub 4}){sub 2} (LLM) was studied in the range of 0,5 - 10mol% doping. The designed furnace growth chamber with controlled atmosphere was successfully constructed and tested under different conditions. Specially, it was tested with the growth of LiF SFC under CF{sub 4} atmosphere showing the expected results. Transparent and homogeneous SCF of Nd:LLM were grown. In the pure fibers was observed facets formation, however, these defects were minimized after tuning of the growth parameters and additionally with the fibers doping. X-ray analysis showed the crystallization of a single phase (space group I4{sub 1}/a); the optical coherence tomography showed the presence of scattering centers only in regions were some growth stability occurred due to the manual process control. The measured Nd{sup 3+} distribution showed uniform incorporation, indicative of a segregation coefficient close to unity in LLM. The potential laser gain of the system was determined using a numerical solution of the rate equations system for the 805nm, CW pumping regime, showing the maximum laser emission gain at 1.064 {mu}m for a Nd{sup 3+}-doping of 5mol%. (author)

  1. Vacuum electronics

    CERN Document Server

    Eichmeier, Joseph A


    Nineteen experts from the electronics industry, research institutes and universities have joined forces to prepare this book. ""Vacuum Electronics"" covers the electrophysical fundamentals, the present state of the art and applications, as well as the future prospects of microwave tubes and systems, optoelectronics vacuum devices, electron and ion beam devices, light and X-ray emitters, particle accelerators and vacuum interrupters. These topics are supplemented by useful information about the materials and technologies of vacuum electronics and vacuum technology.

  2. Bioregenerative system components for microgravity (United States)

    Nevill, Gale E., Jr.; Hessel, Michael I., Jr.


    The goal of the class was to design, fabricate, and test prototype designs that were independent, yet applicable to a Closed Loop Life Support System. The three prototypes chosen were in the areas of agar plant growth, regnerative filtration, and microgravity food preparation. The plant growth group designed a prototype agar medium growth system that incorporates nutrient solution replenishment and post-harvest refurbishment. In addition, the unit emphasizes material containment and minimization of open interfaces. The second project was a filter used in microgravity that has the capability to clean itself. The filters are perforated plates which slide through a duct and are cleaned outside of the flow with a vacuum system. The air in the duct is prevented from flowing outside of the duct by a network of sliding seals. The food preparation group developed a device which dispenses and mixes ingredients and then cooks the mixture in microgravity. The dry ingredients are dispensed from a canister by a ratchet-operated piston. The wet ingredients are dispensed from plastic bags through tubing attached to a syringe. Once inside the mixing chamber, the ingredients are mixed using a collapsible whisk and then pushed into the cooking device.

  3. Vacuum distillation device

    Energy Technology Data Exchange (ETDEWEB)

    Hamer, J.A.; Burg, C.J. Van Der; Kanbier, D.; Heijden, P. Van Der.


    This invention relates to a vacuum distillation device comprising a vacuum distillation column, a furnace provided with a heat exchange tube, and a connecting conduit between the column and the heat exchange tube. Such a device is used to fractionate a hydrocarbon-containing feed sometimes referred to as long residue. An object of this invention is to provide a vacuum distillation device which allows vaporization of a major part of the feed upstream of the column inlet. To this end, the device according to the invention comprises a vacuum distillation device as described above, in which the inner diameter of the heat exchange tube increases along its length to between 2.4 and 3 times the inner diameter of the tube inlet, and in which the inner diameter of the connecting conduit gradually increases along its length to between 2.5 and 5.4 times the inner diameter of the tube outlet. During normal operation of the device of the invention, only less than 50 wt % of the feed is vaporized in the heat exchange tube in the furnace, and more feed is vaporized in the connecting conduit, so that at the outlet end of the conduit the feed comprises about 0.9 kg vapor per kg of feed. The invention provides improved heat transfer in the heat exchange tubes such that fouling is reduced, consequently more heat can be applied per unit of time in the heat exchange tube. This allows either heating of the feed to a higher temperature or increasing the throughput for the same temperature.


    Directory of Open Access Journals (Sweden)

    André Alexandrino Lotto


    Full Text Available This work aims to investigate the phosphorus removal by vacuum from metallurgical grade silicon (MGSi (98.5% to 99% Si. Melting experiments were carried out in a vacuum induction furnace, varying parameters such as temperature, time and relation area exposed to the vacuum / volume of molten silicon. The results of chemical analysis were obtained by inductively coupled plasma (ICP, and evaluated based on thermodynamic and kinetic aspects of the reaction of vaporization of the phosphorus in the silicon. The phosphorus was decreased from 33 to approximately 1.5 ppm after three hours of vacuum treatment, concluding that the evaporation step is the controlling step of the process for parameters of temperature, pressure and agitation used and refining by this process is technically feasible.

  5. United States Air Force Academy's micro-gravity research using G-0307 (United States)

    Turner, G. D.


    The current materials research being done in microgravity solidification and the future experimentation planned onboard a space shuttle mission is reported. The Department of Engineering Mechanics at the USAF Academy is developing a microgravity furnace to be used on board the space shuttle. The microgravity furnace will be used to conduct materials research dealing with such topics as immiscible alloy solidification. The purpose behind this research project is three-fold: to develop a simple, inexpensive, and easy to use furnace to conduct space materials research, to conduct a solidification experiment on a lead-zinc alloy in space that macrosegregates due to gravity, and to provide a research mechanism for students to get involved with space materials research.

  6. Vacuum extraction

    DEFF Research Database (Denmark)

    Maagaard, Mathilde; Oestergaard, Jeanett; Johansen, Marianne


    Objectives. To develop and validate an Objective Structured Assessment of Technical Skills (OSATS) scale for vacuum extraction. Design. Two part study design: Primarily, development of a procedure-specific checklist for vacuum extraction. Hereafter, validationof the developed OSATS scale for vacuum...


    Directory of Open Access Journals (Sweden)

    S. L. Ровин


    Full Text Available In the article there are analyzed the different ways of thermal treatment and melting of polydisperse materials and there are presented the developed by authors original coaxial-cylinder furnace settings, allowing to increase considerably the efficiency and productivity of technological process.  

  8. Automated semiconductor vacuum chemical vapor deposition facility (United States)


    A semiconductor vacuum chemical vapor deposition facility (totally automatic) was developed. Wafers arrived on an air track, automatically loaded into a furnace tube, processed, returned to the track, and sent on to the next operation. The entire process was controlled by a computer.

  9. VACUUM TRAP (United States)

    Gordon, H.S.


    An improved adsorption vacuum trap for use in vacuum systems was designed. The distinguishing feature is the placement of a plurality of torsionally deformed metallic fins within a vacuum jacket extending from the walls to the central axis so that substantially all gas molecules pass through the jacket will impinge upon the fin surfaces. T fins are heated by direct metallic conduction, thereby ol taining a uniform temperature at the adeorbing surfaces so that essentially all of the condensible impurities from the evacuating gas are removed from the vacuum system.

  10. The Canadian Microgravity Sciences Program - Past present and future (United States)

    Wetter, Barry; Saghir, Ziad; Mortimer, Alan


    An overview is given of the Canadian microgravity sciences program emphasizing the development and progress of microgravity-related research in the areas of materials and life sciences. Activities in the area of materials include: (1) materials processing by means of lasers; (2) crystal growth from melts solutions, and/or biological materials; (3) composite, glass, metal, and alloy materials research; and (4) combustion and fluid physics studies. The life-sciences segment incorporates studies of: cardiovascular/muscular acclimatization, radiation dosimetry, aquatic biology, bone decalcification, neurovestibular adaptations, cell cultures, and metabolism. Experimental payloads and processes are described for such infrastructures as the Mir space station, sounding rockets, drop towers, and the International Microgravity Laboratory. In addition to a significant body of useful scientific data the program contributes to the development of useful R&D hardware such as laser systems and a float-zone furnace.

  11. Vacuum Technology

    Energy Technology Data Exchange (ETDEWEB)

    Biltoft, P J


    The environmental condition called vacuum is created any time the pressure of a gas is reduced compared to atmospheric pressure. On earth we typically create a vacuum by connecting a pump capable of moving gas to a relatively leak free vessel. Through operation of the gas pump the number of gas molecules per unit volume is decreased within the vessel. As soon as one creates a vacuum natural forces (in this case entropy) work to restore equilibrium pressure; the practical effect of this is that gas molecules attempt to enter the evacuated space by any means possible. It is useful to think of vacuum in terms of a gas at a pressure below atmospheric pressure. In even the best vacuum vessels ever created there are approximately 3,500,000 molecules of gas per cubic meter of volume remaining inside the vessel. The lowest pressure environment known is in interstellar space where there are approximately four molecules of gas per cubic meter. Researchers are currently developing vacuum technology components (pumps, gauges, valves, etc.) using micro electro mechanical systems (MEMS) technology. Miniature vacuum components and systems will open the possibility for significant savings in energy cost and will open the doors to advances in electronics, manufacturing and semiconductor fabrication. In conclusion, an understanding of the basic principles of vacuum technology as presented in this summary is essential for the successful execution of all projects that involve vacuum technology. Using the principles described above, a practitioner of vacuum technology can design a vacuum system that will achieve the project requirements.

  12. Vacuum mechatronics (United States)

    Hackwood, Susan; Belinski, Steven E.; Beni, Gerardo


    The discipline of vacuum mechatronics is defined as the design and development of vacuum-compatible computer-controlled mechanisms for manipulating, sensing and testing in a vacuum environment. The importance of vacuum mechatronics is growing with an increased application of vacuum in space studies and in manufacturing for material processing, medicine, microelectronics, emission studies, lyophylisation, freeze drying and packaging. The quickly developing field of vacuum mechatronics will also be the driving force for the realization of an advanced era of totally enclosed clean manufacturing cells. High technology manufacturing has increasingly demanding requirements for precision manipulation, in situ process monitoring and contamination-free environments. To remove the contamination problems associated with human workers, the tendency in many manufacturing processes is to move towards total automation. This will become a requirement in the near future for e.g., microelectronics manufacturing. Automation in ultra-clean manufacturing environments is evolving into the concept of self-contained and fully enclosed manufacturing. A Self Contained Automated Robotic Factory (SCARF) is being developed as a flexible research facility for totally enclosed manufacturing. The construction and successful operation of a SCARF will provide a novel, flexible, self-contained, clean, vacuum manufacturing environment. SCARF also requires very high reliability and intelligent control. The trends in vacuum mechatronics and some of the key research issues are reviewed.

  13. Improved Casting Furnace Conceptual Design

    Energy Technology Data Exchange (ETDEWEB)

    Fielding, Randall Sidney [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tolman, David Donald [Idaho National Lab. (INL), Idaho Falls, ID (United States)


    In an attempt to ensure more consistent casting results and remove some schedule variance associated with casting, an improved casting furnace concept has been developed. The improved furnace uses the existing arc melter hardware and glovebox utilities. The furnace concept was designed around physical and operational requirements such as; a charge sized of less than 30 grams, high heating rates and minimal additional footprint. The conceptual model is shown in the report as well as a summary of how the requirements were met.

  14. Model reduction for experimental thermal characterization of a holding furnace (United States)

    Loussouarn, Thomas; Maillet, Denis; Remy, Benjamin; Dan, Diane


    Vacuum holding induction furnaces are used for the manufacturing of turbine blades by loss wax foundry process. The control of solidification parameters is a key factor for the manufacturing of these parts. The definition of the structure of a reduced heat transfer model with experimental identification through an estimation of its parameters is required here. Internal sensors outputs, together with this model, can be used for assessing the thermal state of the furnace through an inverse approach, for a better control. Here, an axisymmetric furnace and its load have been numerically modelled using FlexPDE, a finite elements code. The internal induction heat source as well as the transient radiative transfer inside the furnace are calculated through this detailed model. A reduced lumped body model has been constructed to represent the numerical furnace. The model reduction and the estimation of the parameters of the lumped body have been made using a Levenberg-Marquardt least squares minimization algorithm, using two synthetic temperature signals with a further validation test.

  15. Invariant vacuum (United States)

    Robles-Pérez, Salvador


    We apply the Lewis-Riesenfeld invariant method for the harmonic oscillator with time dependent mass and frequency to the modes of a charged scalar field that propagates in a curved, homogeneous and isotropic spacetime. We recover the Bunch-Davies vacuum in the case of a flat DeSitter spacetime, the equivalent one in the case of a closed DeSitter spacetime and the invariant vacuum in a curved spacetime that evolves adiabatically. In the three cases, it is computed the thermodynamical magnitudes of entanglement between the modes of the particles and antiparticles of the invariant vacuum, and the modification of the Friedmann equation caused by the existence of the energy density of entanglement. The amplitude of the vacuum fluctuations are also computed.

  16. Cosmic vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Chernin, Artur D [P.K. Shternberg State Astronomical Institute at the M.V. Lomonosov Moscow State University, Moscow (Russian Federation)


    Recent observational studies of distant supernovae have suggested the existence of cosmic vacuum whose energy density exceeds the total density of all the other energy components in the Universe. The vacuum produces the field of antigravity that causes the cosmological expansion to accelerate. It is this accelerated expansion that has been discovered in the observations. The discovery of cosmic vacuum radically changes our current understanding of the present state of the Universe. It also poses new challenges to both cosmology and fundamental physics. Why is the density of vacuum what it is? Why do the densities of the cosmic energy components differ in exact value but agree in order of magnitude? On the other hand, the discovery made at large cosmological distances of hundreds and thousands Mpc provides new insights into the dynamics of the nearby Universe, the motions of galaxies in the local volume of 10 - 20 Mpc where the cosmological expansion was originally discovered. (reviews of topical problems)

  17. Vacuum II

    CERN Document Server

    Franchetti, G


    This paper continues the presentation of pumps begun in ‘Vacuum I’. The main topic here is gauges and partial-pressure measurements. Starting from the kinetics of gases, the various strategies for measuring vacuum pressures are presented at an introductory level, with some reference to hardware devices. Partial-pressure measurement techniques are introduced, showing that the principles of ion selection have a direct similarity to particle dynamics in accelerators.

  18. Wet/Dry Vacuum Cleaner (United States)

    Reimers, Harold; Andampour, Jay; Kunitser, Craig; Thomas, Ike


    Vacuum cleaner collects and retains dust, wet debris, and liquids. Designed for housekeeping on Space Station Freedom, it functions equally well in normal Earth Gravity or in microgravity. Generates acoustic noise at comfortably low levels and includes circuitry that reduces electromagnetic interference to other electronic equipment. Draws materials into bag made of hydrophobic sheet with layers of hydrophilic super-absorbing pads at downstream end material. Hydrophilic material can gel many times its own weight of liquid. Blower also provides secondary airflow to cool its electronic components.

  19. CERN wide inventory of existing vacuum and heat treatment furnaces

    CERN Document Server

    Milani, Adrien


    L’utilisation des fours au CERN a plusieurs objectifs (Traitement thermique, brasage, séchage, polymérisation, ... ). Les fours sont donc répartis dans les différents départements, en fonction de l’utilisation de chacun. Cependant il n’existe pas à l’heure actuelle de référencement permettant de connaitre la présence de chaque four ainsi que leurs caractéristiques techniques. L’objectif de mon stage a donc été de créer un inventaire des fours de traitement thermique présents au CERN, afin de connaitre précisément leurs applications possibles. Cette base de données permettra entre autre aux différents départements de savoir quelle personne contacter en fonction de l’utilisation voulue.

  20. STS-47 MS Davis uses SLJ Rack 8 continuous heating furnace (CHF) on OV-105 (United States)


    STS-47 Mission Specialist (MS) N. Jan Davis, wearing gloves, conducts experiment M13, Fabrication of Si-As-Te:Ni Ternary Amorphous Semiconductor in Microgravity, using the continuous heating furnace (CHF) located in the Spacelab Japan (SLJ) module on Rack 8 - NASDA Material Sciences. CHF provided temperatures up to 1,300 degrees Celsius and rapid cooling to two sets of samples concurrently. This was one of the many experiments designed and monitored by Japan's National Space Development Agency (NASDA).

  1. Review of furnace modeling

    Energy Technology Data Exchange (ETDEWEB)

    Krishna, C. R.


    There has been a spurt of recent activity in developing and applying numerical modeling to combustors and furnaces. The purpose of this review is to provide a brief overview of these recent developments and draw conclusions on the scope for further work in the area of modeling. A brief qualitative review of the various models that have been developed is presented. The models show a progressive recognition of the complexity of turbulence-chemistry interactions and attempts to include more recent submodels of such interactions. There are attempts to incorporate the three-dimensional character of fluid flows and solve the elliptic equations arising in recirculating flows. Flux models of radiation transfer are being included in the energy transport equations. Efficient numerical algorithms are being developd to solve the finite difference form of a set of elliptic, partial differential equations. The test of the success of modeling lies, obviously, in comparison with experimental measurements. Such experiments are being undertaken, but, the techniques of measurements also need development before detailed comparison can be made. The measurements made seem to indicate qualitative agreement of model predictions with limited laboratory measurements. It is concluded from the review that there is still need for development in several areas including turbulence (and turbulence-chemistry interactions) modeling, liquid and solid fuel introduction, interaction with the flow and combustion, models for soot formation, and experimental validation.

  2. Fossil fuel furnace reactor (United States)

    Parkinson, William J.


    A fossil fuel furnace reactor is provided for simulating a continuous processing plant with a batch reactor. An internal reaction vessel contains a batch of shale oil, with the vessel having a relatively thin wall thickness for a heat transfer rate effective to simulate a process temperature history in the selected continuous processing plant. A heater jacket is disposed about the reactor vessel and defines a number of independent controllable temperature zones axially spaced along the reaction vessel. Each temperature zone can be energized to simulate a time-temperature history of process material through the continuous plant. A pressure vessel contains both the heater jacket and the reaction vessel at an operating pressure functionally selected to simulate the continuous processing plant. The process yield from the oil shale may be used as feedback information to software simulating operation of the continuous plant to provide operating parameters, i.e., temperature profiles, ambient atmosphere, operating pressure, material feed rates, etc., for simulation in the batch reactor.

  3. Vacuum Valve

    CERN Multimedia


    This valve was used in the Intersecting Storage Rings (ISR) to protect against the shock waves that would be caused if air were to enter the vacuum tube. Some of the ISR chambers were very fragile, with very thin walls - a design required by physicists on the lookout for new particles.

  4. Better VPS Fabrication of Crucibles and Furnace Cartridges (United States)

    Holmes, Richard R.; Zimmerman, Frank R.; O'Dell, J. Scott; McKechnie, Timothy N.


    An experimental investigation has shown that by (1) vacuum plasma spraying (VPS) of suitable refractory metal alloys on graphite mandrels, and then (2) heat-treating the VPS alloy deposits under suitable conditions, it is possible to fabricate improved crucibles and furnace cartridges that could be used at maximum temperatures between 1,400 and 1,600 C and that could withstand chemical attack by the materials to be heated in the crucibles and cartridges. Taken by itself, the basic concept of fabricating furnace cartridges by VPS of refractory materials onto graphite mandrels is not new; taken by itself, the basic concept of heat treatment of VPS deposits for use as other than furnace cartridges is also not new; however, prior to this investigation, experimental crucibles and furnace cartridges fabricated by VPS had not been heat treated and had been found to be relatively weak and brittle. Accordingly, the investigation was directed toward determining whether certain combinations of (1) refractory alloy compositions, (2) VPS parameters, and (3) heat-treatment parameters could result in VPS-fabricated components with increased ductility.

  5. ISS Microgravity Research Payload Training Methodology (United States)

    Schlagheck, Ronald; Geveden, Rex (Technical Monitor)


    The NASA Microgravity Research Discipline has multiple categories of science payloads that are being planned and currently under development to operate on various ISS on-orbit increments. The current program includes six subdisciplines; Materials Science, Fluids Physics, Combustion Science, Fundamental Physics, Cellular Biology and Macromolecular Biotechnology. All of these experiment payloads will require the astronaut various degrees of crew interaction and science observation. With the current programs planning to build various facility class science racks, the crew will need to be trained on basic core operations as well as science background. In addition, many disciplines will use the Express Rack and the Microgravity Science Glovebox (MSG) to utilize the accommodations provided by these facilities for smaller and less complex type hardware. The Microgravity disciplines will be responsible to have a training program designed to maximize the experiment and hardware throughput as well as being prepared for various contingencies both with anomalies as well as unexpected experiment observations. The crewmembers will need various levels of training from simple tasks as power on and activate to extensive training on hardware mode change out to observing the cell growth of various types of tissue cultures. Sample replacement will be required for furnaces and combustion type modules. The Fundamental Physics program will need crew EVA support to provide module change out of experiment. Training will take place various research centers and hardware development locations. It is expected that onboard training through various methods and video/digital technology as well as limited telecommunication interaction. Since hardware will be designed to operate from a few weeks to multiple research increments, flexibility must be planned in the training approach and procedure skills to optimize the output as well as the equipment maintainability. Early increment lessons learned

  6. Cardiovascular regulation in microgravity (United States)

    Blomqvist, C. G.; Lane, L. D.; Wright, S. J.; Meny, G. M.; Buckey, J. C.; Levine, B. D.; Gaffney, F. A.; Watenpaugh, D. E.; Arbeille, P.; Baisch, F.


    The human cardiovascular adaptation to microgravity was investigated in the framework of the German Spacelab D2 mission. Preflight and postflight studies were performed to examine the relationship between disuse atrophy and the function of cardiac and skeletal muscles. Special attention was given to fluid load responses and postflight orthostatic hypotension. The preflight measurements were obtained, in supine and sitting positions. These measurements, carried out in the four D2 crew members, were performed six and nine months before flight and on mission day number five. The results obtained on the male crew showed that the stroke volume data from microgravity are virtually identical to preflight measurements in the sitting position.

  7. New PSA high concentration solar furnace SF40 (United States)

    Rodriguez, Jose; Cañadas, Inmaculada; Zarza, Eduardo


    A new solar furnace has been designed and built at Plataforma Solar de Almería. In this work, its main components such as heliostat, concentrator, attenuator and test table, and the method used to align them are described. Other equipment like the auxiliary systems necessary for the solar operation, vacuum chamber and gas system are outlined too. Finally, the thermal characteristics of the focus were measured during a test campaign, where different planes along the optical axis were scanned with a radiometer, and the peak flux was obtained and is presented in the last section of this report.

  8. High Efficiency Solar Furnace Core Project (United States)

    National Aeronautics and Space Administration — It is proposed to develop a high efficiency solar furnace core that greatly lessens the heat losses from the furnace core, either greatly reducing the amount of...

  9. Electrostatic Levitation Furnace for the ISS (United States)

    Murakami, Keiji; Koshikawa, Naokiyo; Shibasaki, Kohichi; Ishikawa, Takehiko; Okada, Junpei; Takada, Tetsuya; Arai, Tatsuya; Fujino, Naoki; Yamaura, Yukiko


    JAXA (Japan Aerospace Exploration Agency) has just started the development of Electrostatic Levitation Furnace to be launched in 2014 for the ISS. This furnace can control the sample position with electrostatic force and heat it above 2000 degree Celsius using semiconductor laser from four different directions. The announcement of Opportunity will be issued soon for this furnace. In this paper, we will show the specifications of this furnace and also the development schedule

  10. Training Guidelines: Glass Furnace Operators. (United States)

    Ceramics, Glass, and Mineral Products Industry Training Board, Harrow (England).

    Technological development in the glass industry is constantly directed towards producing high quality glass at low operating costs. Particularly, changes have taken place in melting methods which mean that the modern furnace operator has greater responsibilities than any of his predecessors. The complexity of control systems, melting rates, tank…

  11. Cartilage Engineering and Microgravity (United States)

    Toffanin, R.; Bader, A.; Cogoli, A.; Carda, C.; Fantazzini, P.; Garrido, L.; Gomez, S.; Hall, L.; Martin, I.; Murano, E.; Poncelet, D.; Pörtner, R.; Hoffmann, F.; Roekaerts, D.; Ronney, P.; Triebel, W.; Tummers, M.


    The complex effects of mechanical forces and growth factors on articular cartilage development still need to be investigated in order to identify optimal conditions for articular cartilage repair. Strictly controlled in vitro studies under modelled or space microgravity conditions can improve our understanding of the fundamental role of gravity in articular cartilage development. The main objective of this Topical Team is to use modelled microgravity as a tool to elucidate the fundamental science of cartilage regeneration. Particular attention is, therefore, given to the effects of physical forces under altered gravitational conditions, applied using controlled bioreactor systems, on cell metabolism, cell differentiation and tissue development. Specific attention is also directed toward the potential advantages of using magnetic resonance methods for the non-destructive characterisation of scaffolds, chondrocytes-polymer constructs and tissue engineered cartilage.

  12. Microgravity particle reduction system (United States)

    Brandon, Vanessa; Joslin, Michelle; Mateo, Lili; Tubbs, Tracey


    The Controlled Ecological Life Support System (CELSS) project, sponsored by NASA, is assembling the knowledge required to design, construct, and operate a system which will grow and process higher plants in space for the consumption by crew members of a space station on a long term space mission. The problem of processing dry granular organic materials in microgravity is discussed. For the purpose of research and testing, wheat was chosen as the granular material to be ground into flour. Possible systems which were devised to transport wheat grains into the food processor, mill the wheat into flour, and transport the flour to the food preparation system are described. The systems were analyzed and compared and two satisfactory systems were chosen. Prototypes of the two preferred systems are to be fabricated next semester. They will be tested under simulated microgravity conditions and revised for maximum effectiveness.

  13. Microgravity Materials Science Laboratory (United States)

    Grisaffe, S. J.


    A Microgravity Materials Science Laboratory (MMSL) has been planned, designed, and is being developed. This laboratory will support related efforts to define the requirements for the Microgravity and Materials Processing Laboratory (MMPF) and the MMPF Test Bed for the Space Station. The MMSL will serve as a check out and training facility for science mission specialists for STS, Spacelab and Space Station prior to the full operation of the MMPF Test Bed. The focus of the MMSL will be on experiments related to the understanding of metal/ceramic/glass solidification, high perfection crystal growth and fluid physics. This ground-based laboratory will be used by university/industry/government researchers to examine and become familiar with the potential of new microgravity materials science concepts and to conduct longer term studies aimed at fully developing a l-g understanding of materials and processing phenomena. Such research will help create new high quality concepts for space experiments and will provide the basis for modeling, theories, and hypotheses upon which key space experiments can be defined and developed.

  14. Alkaline carbonates in blast furnace process

    Directory of Open Access Journals (Sweden)

    P. Besta


    Full Text Available The production of iron in blast furnaces is a complex of physical, chemical and mechanical processes. The input raw materials contain not only metallic components, but also a number of negative elements. The most important negative elements include alkaline carbonates. They can significantly affect the course of the blast furnace process and thus the overall performance of the furnace. As a result of that, it is essential to accurately monitor the alkali content in the blast furnace raw materials. The article analyzes the alkali content in input and output raw materials and their impact on the blast furnace process.

  15. Vacuum phenomenon. (United States)

    Yanagawa, Youichi; Ohsaka, Hiromichi; Jitsuiki, Kei; Yoshizawa, Toshihiko; Takeuchi, Ikuto; Omori, Kazuhiko; Oode, Yasumasa; Ishikawa, Kouhei


    This article describes the theory of the formation of the vacuum phenomenon (VP), the detection of the VP, the different medical causes, the different locations of the presentation of the VP, and the differential diagnoses. In the human body, the cavitation effect is recognized on radiological studies; it is called the VP. The mechanism responsible for the formation of the VP is as follows: if an enclosed tissue space is allowed to expand as a rebound phenomenon after an external impact, the volume within the enclosed space will increase. In the setting of expanding volume, the pressure within the space will decrease. The solubility of the gas in the enclosed space will decrease as the pressure of the space decreases. Decreased solubility allows a gas to leave a solution. Clinically, the pathologies associated with the VP have been reported to mainly include the normal joint motion, degeneration of the intervertebral discs or joints, and trauma. The frequent use of CT for trauma patients and the high spatial resolution of CT images might produce the greatest number of chances to detect the VP in trauma patients. The VP is observed at locations that experience a traumatic impact; thus, an analysis of the VP may be useful for elucidating the mechanism of an injury. When the VP is located in the abdomen, it is important to include perforation of the digestive tract in the differential diagnosis. The presence of the VP in trauma patients does not itself influence the final outcome.

  16. NASA Microgravity Materials Science Conference (United States)

    Gillies, D. C. (Compiler); McCauley, D. E. (Compiler)


    The Microgravity Materials Science Conference was held July 14-16, 1998 at the Von Braun Center in Huntsville, AL. It was organized by the Microgravity Materials Science Discipline Working Group, sponsored by the Microgravity Research Division at NASA Headquarters, and hosted by the NASA Marshall Space Flight Center and the Alliance for Microgravity Materials Science and Applications. It was the third NASA conference of this type in the microgravity materials science discipline. The microgravity science program sponsored approximately 125 investigations and 100 principal investigators in FY98, almost all of whom made oral or poster presentations at this conference. The conference's purpose was to inform the materials science community of research opportunities in reduced gravity in preparation for a NASA Research Announcement scheduled for release in late 1998 by the Microgravity Research Division at NASA Headquarters. The conference was aimed at materials science researchers from academia, industry, and government. A tour of the Marshall Space Flight Center microgravity research facilities was held on July 16, 1998. This volume is comprised of the research reports submitted by the principal investigators after the conference.

  17. Computer simulation of rapid crystal growth under microgravity (United States)

    Hisada, Yasuhiro; Saito, Osami; Mitachi, Koshi; Nishinaga, Tatau

    We are planning to grow a Ge single crystal under microgravity by the TR-IA rocket in 1992. The furnace temperature should be controlled so as to finish the crystal growth in a quite short time interval (about 6 min). This study deals with the computer simulation of rapid crystal growth in space to find the proper conditions for the experiment. The crystal growth process is influenced by various physical phenomena such as heat conduction, natural and Marangoni convections, phase change, and radiation from the furnace. In this study, a 2D simulation with axial symmetry is carried out, taking into account the radiation field with a specific temperature distribution of the furnace wall. The simulation program consists of four modules. The first module is applied for the calculation of the parabolic partial differential equation by using the control volume method. The second one evaluates implicitly the phase change by the enthalpy method. The third one is for computing the heat flux from surface by radiation. The last one is for calculating with the Monte Carlo method the view factors which are necessary to obtain the heat flux.

  18. Supercritical microgravity droplet vaporization (United States)

    Hartfield, J.; Curtis, E.; Farrell, P.


    Supercritical droplet vaporization is an important issue in many combustion systems, such as liquid fueled rockets and compression-ignition (diesel) engines. In order to study the details of droplet behavior at these conditions, an experiment was designed to provide a gas phase environment which is above the critical pressure and critical temperature of a single liquid droplet. In general, the droplet begins as a cold droplet in the hot, high pressure environment. In order to eliminate disruptions to the droplet by convective motion in the gas, forced and natural convection gas motion are required to be small. Implementation of this requirement for forced convection is straightforward, while reduction of natural convection is achieved by reduction in the g-level for the experiment. The resulting experiment consists of a rig which can stably position a droplet without restraint in a high-pressure, high temperature gas field in microgravity. The microgravity field is currently achieved by dropping the device in the NASA Lewis 2.2 second drop tower. The performance of the experimental device and results to date are presented.

  19. Measurement of airflow in residential furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Biermayer, Peter J.; Lutz, James; Lekov, Alex


    In order to have a standard for furnaces that includes electricity consumption or for the efficiency of furnace blowers to be determined, it is necessary to determine the airflow of a furnace or furnace blower. This study focused on airflow testing, in order to determine if an existing test method for measuring blower airflow could be used to measure the airflow of a furnace, under conditions seen in actual installations and to collect data and insights into the operating characteristics of various types of furnace blowers, to use in the analysis of the electricity consumption of furnaces. Results of the measured airflow on furnaces with three types of blower and motor combinations are presented in the report. These included: (1) a forward-curved blower wheel with a typical permanent split capacitor (PSC) motor, (2) a forward-curved blower wheel with an electronically-commutated motor (ECM), and (3) a prototype blower, consisting of a backward-inclined blower wheel matched to an ECM motor prototype, which is being developed as an energy-saving alternative to conventional furnace blowers. The testing provided data on power consumption, static and total pressure, and blower speed.

  20. Analysis of biological effects in human endothelial cells after stimulated microgravity (United States)

    Min, Zhang; Sun, Yeqing; Xu, Dan

    Space environment is characterized by strong radiation, ultra-high vacuum, weak magnetic field and microgravity. Among them, microgravity (10-4-10-6g) in space is different from gravity (1g) on earth, possibly causing visual disorders, muscle alterations, bone loss and dysfunction of cardiovascular systems. To study about microgravity environment, the most advanced rotary cell culture system (RCCS-1) was used to do stimulated microgravity (SMG) experiments in the ground. Up to now, most of studies focus on the biological effects under stimulated microgravity, but it is less known about the cellular response after stimulated microgravity. In the present study, we explored the subsequent effects of stimulated microgravity on human endothelial cells (HUVEC-C) after these cells were cultured on RCCS-1 for 48 hours. We co-cultured HUVEC-C cells with HillexⅡmicrocarriers in 60-mm culture dishes for 24h, followed by transferring them to RCCS-1 so that cells remain to be the state of SMG. In parallel, HUVEC-C cells were co-cultured with microcarriers in the ground condition. We found that stimulated microgravity induced cytoskeleton remodeling, cell cycle G2/M arrest and cellular senescence, consistent with previous reports. To study the subsequent effects of stimulated microgravity, we make cells detach from microcarriers and observed various effects including cell growth, cell adhesion, cytoskeleton, cell cycle, apoptosis and senescence. The results showed that those cells undergoing stimulated microgravity appeared obvious growth inhibition, a transition from the decrease in cell adhesion ability and cytoskeleton remodeling within 24h to induction of apoptosis and senescence-like phenotype in the later time with slight changes in cell cycle. Analysis of protein expression in western blot demonstrated that apoptosis-related protein PTEN was up-regulated on the time-dependent pattern after stimulated microgravity, indicating that PTEN-PI3K-Akt pathway might play an

  1. Microgravity contact pumping (United States)

    Lowry, Brian; Thiessen, David


    Phase separations by gravity are an integral part of the vast majority of macroscopic terrestrial chemical and metallurgical engineering processes. Captured droplets are an obvious workaround in microgravity or microscale environments. Either chambered liquid bridges or helical supports permit the easy conversion of macroscopic terrestrial processes such as distillation and stripping. Chambered systems pump by capillary forces and are extremely resistant to blowout or rupture. The chambering allows staged processes such as distillation. However, chambered systems require mechanical systems of valves and may be expensive to manufacture. Helical supports permit infinite near-open cylindrical volumes of fluid with a single interface, but cannot support flow rates as great as chambered systems. The two modes are characterized and compared.

  2. Straight Ahead in Microgravity (United States)

    Wood, S. J.; Vanya, R. D.; Clement, G.


    This joint ESA-NASA study will address adaptive changes in spatial orientation related to the subjective straight ahead, and the use of a vibrotactile sensory aid to reduce perceptual errors. The study will be conducted before and after long-duration expeditions to the International Space Station (ISS) to examine how spatial processing of target location is altered following exposure to microgravity. This project specifically addresses the sensorimotor research gap "What are the changes in sensorimotor function over the course of a mission?" Six ISS crewmembers will be requested to participate in three preflight sessions (between 120 and 60 days prior to launch) and then three postflight sessions on R+0/1 day, R+4 +/-2 days, and R+8 +/-2 days. The three specific aims include: (a) fixation of actual and imagined target locations at different distances; (b) directed eye and arm movements along different spatial reference frames; and (c) the vestibulo-ocular reflex during translation motion with fixation targets at different distances. These measures will be compared between upright and tilted conditions. Measures will then be compared with and without a vibrotactile sensory aid that indicates how far one has tilted relative to the straight-ahead direction. The flight study was been approved by the medical review boards and will be implemented in the upcoming Informed Crew Briefings to solicit flight subject participation. Preliminary data has been recorded on 6 subjects during parabolic flight to examine the spatial coding of eye movements during roll tilt relative to perceived orientations while free-floating during the microgravity phase of parabolic flight or during head tilt in normal gravity. Binocular videographic recordings obtained in darkness allowed us to quantify the mean deviations in gaze trajectories along both horizontal and vertical coordinates relative to the aircraft and head orientations. During some parabolas, a vibrotactile sensory aid provided

  3. Materials treatment at solar furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, D.


    In the modern age, beginning in the fifties, solar furnaces have been used as a tool for research in materials technologies and treatment, as well as chemical reactor test beds. However, this is not the first time man has attempted to use sunlight as a means of manipulating the materials that surround us. During the Renaissance, Leonardo da Vinci proposed the construction of a six-kilometer parabolic mirror able to heat any boiler for a dye factory and the sculptor Andrea del Verrochio used a solar mirror to weld the parts of a spherical copper support for a lantern at Santa Maria del Fiore in Florence. At present, the materials treatment work in solar furnaces may be summarized as follows: the study of physical-thermal properties of materials at high temperatures-innovative treatments impossible to carry out with the conventional manufacturing processes, which improve certain properties of materials that are going to work under very severe conditions improving the results of industrial materials treatments such as laser surface tempering testing under laboratory conditions of materials which will have to undergo extreme conditions at high temperatures (ceramic coating of aircraft and space vehicles, turbine blades, power brake discs, electrical contacts, nuclear reactors, etc.) With regard to high temperature chemical applications, experiments are being carried out in detoxification, gasification of solid fuels, chemical reaction kinetics studies and direct absorption particle reactors. (Author) 31 refs.

  4. Materials treatment at Solar Furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, D. [Ciemat. Plataforma Solar de Almeria. Almeria (Spain)


    In the modern age, beginning in the fifties, solar furnaces have been used as a tool for research in materials technologies and treatment, as well as chemical reactor test beds. However, this is not the first time man has attempted to use sunlight as a means of manipulating the materials that surround us. During the Renaissance, Leonardo da Vinci proposed the construction of a six-kilometer parabolic mirror able to heat any boiler for a dye factory and the sculptor Andrea del Verrochio used a solar mirror to weld the parts of a spherical copper support for a lantern at Santa Maria del Fiore in Florence. At present, the materials treatment work in solar furnaces may be summarized as follows: -the study of physical-thermal properties of materials at high temperatures -innovative treatments impossible to carry out with the conventional manufacturing processes, which improve certain properties of materials that are going to work under very severe conditions -improving the results of industrial materials treatments such as laser surface tempering -testing under laboratory conditions of materials which will have to undergo extreme conditions at high temperatures (ceramic coating of aircraft and space vehicles, turbine blades, power brake discs, electrical contacts, nuclear reactors, etc.) With regard to high temperature chemical applications, experiments are being carried out in detoxification, gasification of solid fuels, chemical reaction kinetics studies and direct absorption particle reactors. (Author) 31 refs.

  5. Robust Low Cost Liquid Rocket Combustion Chamber by Advanced Vacuum Plasma Process (United States)

    Holmes, Richard; Elam, Sandra; McKechnie, Timothy; Hickman, Robert; Stinson, Thomas N. (Technical Monitor)


    Next-generation, regeneratively cooled rocket engines require materials that can meet high temperatures while resisting the corrosive oxidation-reduction reaction of combustion known as blanching, the main cause of engine failure. A project was initiated at NASA-Marshal Space Flight Center (MSFC) to combine three existing technologies to build and demonstrate an advanced liquid rocket engine combustion chamber that would provide a 100 mission life. Technology developed in microgravity research to build cartridges for space furnaces was utilized to vacuum plasma spray (VPS) a functional gradient coating on the hot wall of the combustion liner as one continuous operation, eliminating any bondline between the coating and the liner. The coating was NiCrAlY, developed previously as durable protective coatings on space shuttle high pressure fuel turbopump (HPFTP) turbine blades. A thermal model showed that 0.03 in. NiCrAlY applied to the hot wall of the combustion liner would reduce the hot wall temperature 200 F, a 20% reduction, for longer life. Cu-8Cr-4Nb alloy, which was developed by NASA-Glenn Research Center (GRC), and which possesses excellent high temperature strength, creep resistance, and low cycle fatigue behavior combined with exceptional thermal stability, was utilized as the liner material in place of NARloy-Z. The Cu-8Cr-4Nb material exhibits better mechanical properties at 650 C (1200 F) than NARloy-Z does at 538 C (1000 F). VPS formed Cu-8Cr-4Nb combustion chamber liners with a protective NiCrAlY functional gradient coating have been hot fire tested, successfully demonstrating a durable coating for the first time. Hot fire tests along with tensile and low cycle fatigue properties of the VPS formed combustion chamber liners and witness panel specimens are discussed.

  6. Refractory of Furnaces to Reduce Environmental Impact

    Energy Technology Data Exchange (ETDEWEB)

    Hanzawa, Shigeru, E-mail: [NGK Insulators, LTD., Mizuho, Nagoya (Japan)


    The energy load of furnaces used in the manufacturing process of ceramics is quite large. Most of the environmental impact of ceramics manufacturing is due to the CO{sub 2} produced from this high energy load. To improve this situation, R and D has focused on furnace systems and techniques of control in order to reduce energy load. Since furnaces are comprised of refractory, consideration of their mechanical and thermal characteristics is important. Herein are described several refractory types which were chosen through comparison of the characteristics which contribute to heat capacity reduction, heat insulating reinforcement and high emissivity, thereby improving thermal radiation heat transfer efficiency to the ceramic articles. One selected refractory material which will reduce the environmental impact of a furnace, chosen considering low heat capacity and high emissivity characteristics, is SiC. In this study, thermal radiation heat transfer efficiency improvement and its effect on ceramic articles in the furnace and oxidation behaviour were investigated at 1700K. A high density SiC refractory, built into the furnace at construction, has relatively high oxidation durability and has the ability to reduce environmental impact-CO{sub 2} by 10 percent by decreasing the furnace's energy load. However, new oxidation prevention techniques for SiC will be necessary for long-term use in industrial furnaces, because passive to active oxidation transition behaviour of commercial SiC refractory is coming to close ideal.

  7. Fabrication of graphene from graphite by a thermal assisted vacuum arc discharge system (United States)

    Cheng, Guo-Wei; Chu, Kevin; Chen, Jeng Shiung; Tsai, Jeff T. H.


    In this study, graphene was fabricated on copper foils using a high temperature furnace embedded in a vacuum arc discharge method. Combining the advantages of chemical vapor deposition and vacuum arc discharge, single-layer graphene can be fabricated at 600 °C base temperature from the mini furnace embedded with a fast heating via the photon radiation from the vacuum arc to 1100 °C on the substrates' surface. The optimal fabrication condition was determined through a series of experiments on ambient pressure, processing time, arc currents, and the cooling process. Observations by scanning electron microscopy, Raman spectroscopy, and optical microscopy showed that the main products were single-layer graphene, which has a uniform thickness across the entire substrate. The results demonstrated that the combination of a vacuum arc with a thermal method that uses graphite as a carbon source provides a low-cost and straight forward method to synthesize graphene films for graphene-based applications.

  8. Research Regarding the Anticorosiv Protection of Atmospheric and Vacuum Distillation Unit that Process Crude Oil


    M. Morosanu; M. G. Petrescu; N. N. Antonescu


    Due to high boiling temperature, organic acids are present in the warmer areas of metal equipment from atmospheric and vacuum distillation units and determine, increased corrosion processes in furnace tubes, transfer lines, metal equipment within the distillation columns etc. In order to protect the corrosion of metal equipment from atmospheric and vacuum distillation units, against acids, de authors researched solution which integrates corrosion inhibitors and selecting materials for equi...

  9. Smoldering Combustion Experiments in Microgravity (United States)

    Walther, David C.; Fernandez-Pello, A. Carlos; Urban, David L.


    The Microgravity Smoldering Combustion (MSC) experiment is part of a study of the smolder characteristics of porous combustible materials in a microgravity environment. Smoldering is a non-flaming form of combustion that takes place in the interior of porous materials and takes place in a number of processes ranging from smoldering of porous insulation materials to high temperature synthesis of metals. The objective of the study is to provide a better understanding of the controlling mechanisms of smolder, both in microgravity and normal-gravity. As with many forms of combustion, gravity affects the availability of oxidizer and transport of heat, and therefore the rate of combustion. Microgravity smolder experiments, in both a quiescent oxidizing environment, and in a forced oxidizing flow have been conducted aboard the NASA Space Shuttle (STS-69 and STS-77 missions) to determine the effect of the ambient oxygen concentration and oxidizer forced flow velocity on smolder combustion in microgravity. The experimental apparatus is contained within the NASA Get Away Special Canister (GAS-CAN) Payload. These two sets of experiments investigate the propagation of smolder along the polyurethane foam sample under both diffusion driven and forced flow driven smoldering. The results of the microgravity experiments are compared with identical ones carried out in normal gravity, and are used to verify present theories of smolder combustion. The results of this study will provide new insights into the smoldering combustion process. Thermocouple histories show that the microgravity smolder reaction temperatures (Ts) and propagation velocities (Us) lie between those of identical normal-gravity upward and downward tests. These observations indicate the effect of buoyancy on the transport of oxidizer to the reaction front.

  10. Blood flow and microgravity (United States)

    Bureau, Lionel; Coupier, Gwennou; Dubois, Frank; Duperray, Alain; Farutin, Alexander; Minetti, Christophe; Misbah, Chaouqi; Podgorski, Thomas; Tsvirkun, Daria; Vysokikh, Mikhail


    The absence of gravity during space flight can alter cardio-vascular functions partially due to reduced physical activity. This affects the overall hemodynamics, and in particular the level of shear stresses to which blood vessels are submitted. Long-term exposure to space environment is thus susceptible to induce vascular remodeling through a mechanotransduction cascade that couples vessel shape and function with the mechanical cues exerted by the circulating cells on the vessel walls. Central to such processes, the glycocalyx - i.e. the micron-thick layer of biomacromolecules that lines the lumen of blood vessels and is directly exposed to blood flow - is a major actor in the regulation of biochemical and mechanical interactions. We discuss in this article several experiments performed under microgravity, such as the determination of lift force and collective motion in blood flow, and some preliminary results obtained in artificial microfluidic circuits functionalized with endothelium that offer interesting perspectives for the study of the interactions between blood and endothelium in healthy condition as well as by mimicking the degradation of glycocalyx caused by long space missions. A direct comparison between experiments and simulations is discussed. xml:lang="fr"

  11. Acoustic characteristics of electric arc furnaces (United States)

    Cherednichenko, V. S.; Bikeev, R. A.; Cherednichenko, A. V.; Ognev, A. M.


    A mathematical model is constructed to describe the appearance and development of the noise characteristics of superpower electric arc furnaces. The noise formation is shown to be related to the pulsation of the axial plasma flows in arc discharges because of the electrodynamic pressure oscillations caused by the interaction of the self-magnetic field with the current passing in an arc. The pressure in the arc axis changes at a frequency of 100 Hz at the maximum operating pressure of 66 kPa for an arc current of 80 kA. The main ac arc sound frequencies are multiples of 100 Hz, which is supported in the practice of operation of electric arc furnaces. The sound intensity in the furnace laboratory reaches 160 dB and is decreased to 115-120 dB in the working furnace area due to shielding by the furnace jacket, the molten metal, and the molten slag. The appropriateness of increasing the hermetic sealing of electric furnaces and creating furnaces operating at low currents and high transformer voltages is corroborated.

  12. Miniaturized lab system for future cold atom experiments in microgravity

    CERN Document Server

    Kulas, Sascha; Resch, Andreas; Hartwig, Jonas; Ganske, Sven; Matthias, Jonas; Schlippert, Dennis; Wendrich, Thijs; Ertmer, Wolfgang; Rasel, Ernst Maria; Damjanic, Marcin; Weßels, Peter; Kohfeldt, Anja; Luvsandamdin, Erdenetsetseg; Schiemangk, Max; Grzeschik, Christoph; Krutzik, Markus; Wicht, Andreas; Peters, Achim; Herrmann, Sven; Lämmerzahl, Claus


    We present the technical realization of a compact system for performing experiments with cold $^{87}{\\text{Rb}}$ and $^{39}{\\text{K}}$ atoms in microgravity in the future. The whole system fits into a capsule to be used in the drop tower Bremen. One of the advantages of a microgravity environment is long time evolution of atomic clouds which yields higher sensitivities in atom interferometer measurements. We give a full description of the system containing an experimental chamber with ultra-high vacuum conditions, miniaturized laser systems, a high-power thulium-doped fiber laser, the electronics and the power management. In a two-stage magneto-optical trap atoms should be cooled to the low $\\mu$K regime. The thulium-doped fiber laser will create an optical dipole trap which will allow further cooling to sub-$\\mu$K temperatures. The presented system fulfills the demanding requirements on size and power management for cold atom experiments on a microgravity platform, especially with respect to the use of an op...

  13. Microgravity effect on testicular functions. (United States)

    Ricci, G; Catizone, A; Esposito, R; Galdieri, M


    In mammals spaceflight influences spermatogenesis since spermatogonial germ cell proliferation, compared to synchronous controls, is lightly decreased in irradiated or flown rats. Moreover, changes of the plasmatic testosterone production was described either in flight rats, or in rats maintained in simulated microgravity conditions. The hormonal levels of the astronauts change as it has been previously described, including hormones involved in the regulation of spermatogenesis such as testosterone and luteinizing hormone (LH). In microgravity conditions, human testosterone levels decreased whereas circulating LH levels increased. To study the effect of simulated microgravity on mammalian spermatogenesis we have utilized the Rotary Cell Culture System (RCCS) and we have cultured testicular fragments isolated from prepuberal rats in a chemically defined medium for three days under microgravity conditions. As control we have cultured the same amount of fragments at unit gravity. The morphology of the samples has been studied and the number of proliferating cells has been counted in control samples and in samples maintained in RCCS. The results indicate that the number of duplicating cells in the tubules was significantly increased in the microgravity-cultured fragments. The amount of testosterone secreted in the culture medium has been also evaluated and in RCCS samples the amount of the hormone was higher respect to the control samples.

  14. Nanoscale Vacuum Channel Transistor. (United States)

    Han, Jin-Woo; Moon, Dong-Il; Meyyappan, M


    Vacuum tubes that sparked the electronics era had given way to semiconductor transistors. Despite their faster operation and better immunity to noise and radiation compared to the transistors, the vacuum device technology became extinct due to the high power consumption, integration difficulties, and short lifetime of the vacuum tubes. We combine the best of vacuum tubes and modern silicon nanofabrication technology here. The surround gate nanoscale vacuum channel transistor consists of sharp source and drain electrodes separated by sub-50 nm vacuum channel with a source to gate distance of 10 nm. This transistor performs at a low voltage (3 microamperes). The nanoscale vacuum channel transistor can be a possible alternative to semiconductor transistors beyond Moore's law.

  15. Multipurpose furnace for in situ studies of polycrystalline materials using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Hemant; Zuidwijk, Thim; Geerlofs, Nico; Offerman, S. Erik [Department of Materials Science and Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft (Netherlands); Wattjes, Alix C. [Electronic and Mechanical Support Division (DEMO), Delft University of Technology, Mekelweg 4, 2628 CD Delft (Netherlands); Amirthalingam, Murugaiyan [Materials Innovation Institute, Mekelweg 2, 2628 CD Delft (Netherlands)


    We report a multipurpose furnace designed for studies using synchrotron radiation on polycrystalline materials, namely, metals, ceramics, and (semi)crystalline polymers. The furnace has been designed to carry out three-dimensional (3D) x-ray diffraction measurements but can also be used for other types of synchrotron radiation research. The furnace has a very low thermal gradient across the specimen (<0.2 degree sign C/mm). Accurate determination of the temperature can be carried out by welding a thermocouple to the specimen. The furnace can be rotated over an angle of 90 degree sign in order to determine the crystallographic orientation of each individual grain. It is possible to follow growth kinetics of all grains in the illuminated volume of the specimen. The specimen environment can be controlled varying from vacuum (up to 10{sup -5} mbar) to gas or air filled. The maximum temperature of operation is 1500 degree sign C, with the possibility of achieving high heating (up to 20 deg. C/s) and cooling rates (up to 30 deg. C/s without quenching gas). 3D maps of the microstructure of the specimen can be generated at elevated temperatures by bringing the high-resolution detector close to the specimen. We show an example of a simulation of the heat affected zone during the thermal cycle of a weld in a transformation-induced plasticity steel carried out using the furnace. The unique characteristics of the furnace open possibility of new fields in materials research using synchrotron radiation.

  16. Indian Vacuum Society: The Indian Vacuum Society (United States)

    Saha, T. K.


    The Indian Vacuum Society (IVS) was established in 1970. It has over 800 members including many from Industry and R & D Institutions spread throughout India. The society has an active chapter at Kolkata. The society was formed with the main aim to promote, encourage and develop the growth of Vacuum Science, Techniques and Applications in India. In order to achieve this aim it has conducted a number of short term courses at graduate and technician levels on vacuum science and technology on topics ranging from low vacuum to ultrahigh vacuum So far it has conducted 39 such courses at different parts of the country and imparted training to more than 1200 persons in the field. Some of these courses were in-plant training courses conducted on the premises of the establishment and designed to take care of the special needs of the establishment. IVS also regularly conducts national and international seminars and symposia on vacuum science and technology with special emphasis on some theme related to applications of vacuum. A large number of delegates from all over India take part in the deliberations of such seminars and symposia and present their work. IVS also arranges technical visits to different industries and research institutes. The society also helped in the UNESCO sponsored post-graduate level courses in vacuum science, technology and applications conducted by Mumbai University. The society has also designed a certificate and diploma course for graduate level students studying vacuum science and technology and has submitted a syllabus to the academic council of the University of Mumbai for their approval, we hope that some colleges affiliated to the university will start this course from the coming academic year. IVS extended its support in standardizing many of the vacuum instruments and played a vital role in helping to set up a Regional Testing Centre along with BARC. As part of the development of vacuum education, the society arranges the participation of

  17. 2002 Microgravity Materials Science Conference (United States)

    Gillies, Donald (Editor); Ramachandran, Narayanan (Editor); Murphy, Karen (Editor); McCauley, Dannah (Editor); Bennett, Nancy (Editor)


    The 2002 Microgravity Materials Science Conference was held June 25-26, 2002, at the Von Braun Center, Huntsville, Alabama. Organized by the Microgravity Materials Science Discipline Working Group, sponsored by the Physical Sciences Research Division, NASA Headquarters, and hosted by NASA Marshall Space Flight Center and member institutions under the Cooperative Research in Biology and Materials Science (CORBAMS) agreement, the conference provided a forum to review the current research and activities in materials science, discuss the envisioned long-term goals, highlight new crosscutting research areas of particular interest to the Physical Sciences Research Division, and inform the materials science community of research opportunities in reduced gravity. An abstracts book was published and distributed at the conference to the approximately 240 people attending, who represented industry, academia, and other NASA Centers. This CD-ROM proceedings is comprised of the research reports submitted by the Principal Investigators in the Microgravity Materials Science program.

  18. Cast construction elements for heat treatment furnaces

    Directory of Open Access Journals (Sweden)

    B. Piekarski


    Full Text Available The study presents sketches and photos of the cast creep-resistant components used in various types of heat treatment furnaces. The shape of the elements results from the type of the operation carried out in the furnace, while dimensions are adjusted to the size of the furnace working chamber. The castings are mainly made from the high-alloyed, austenitic chromium-nickel or nickel-chromium steel, selecting the grade in accordance with the furnace operating conditions described by the rated temperature, the type and parameters of the applied operating atmosphere, and the charge weight. Typical examples in this family of construction elements are: crucibles, roller tracks, radiant tubes and guides. The majority of castings are produced in sand moulds.

  19. Blast furnace supervision and control system

    Energy Technology Data Exchange (ETDEWEB)

    Remorino, M.; Lingiardi, O.; Zecchi, M. [Siderar S.A.I.C./Ingdesi, San Nicolas (Argentina)


    On December 1992, a group of companies headed by Techint, took over Somisa, the state-owned integrated steel plant located at San Nicolas, Province of Buenos Aires, Argentina, culminating an ambitious government privatization scheme. The blast furnace 2 went into a full reconstruction and relining in January 1995. After a 140 MU$ investment the new blast furnace 2 was started in September 1995. After more than one year of operation of the blast furnace the system has proven itself useful and reliable. The main reasons for the success of the system are: same use interface for all blast furnace areas -- operation, process, maintenance and management, (full horizontal and vertical integration); and full accessibility to all information and process tools though some restrictions apply to field commands (people empowerment). The paper describes the central system.

  20. Multiple hearth furnace for reducing iron oxide

    Energy Technology Data Exchange (ETDEWEB)

    Brandon, Mark M [Charlotte, NC; True, Bradford G [Charlotte, NC


    A multiple moving hearth furnace (10) having a furnace housing (11) with at least two moving hearths (20) positioned laterally within the furnace housing, the hearths moving in opposite directions and each moving hearth (20) capable of being charged with at least one layer of iron oxide and carbon bearing material at one end, and being capable of discharging reduced material at the other end. A heat insulating partition (92) is positioned between adjacent moving hearths of at least portions of the conversion zones (13), and is capable of communicating gases between the atmospheres of the conversion zones of adjacent moving hearths. A drying/preheat zone (12), a conversion zone (13), and optionally a cooling zone (15) are sequentially positioned along each moving hearth (30) in the furnace housing (11).

  1. Chamberless residential warm air furnace design

    Energy Technology Data Exchange (ETDEWEB)

    Godfree, J. [Product Design consultant, Pugwash (Canada)


    This brief paper is an introduction to the concept of designing residential warm air furnaces without combustion chambers. This is possible since some small burners do not require the thermal support of a combustion chamber to complete the combustion process.


    Directory of Open Access Journals (Sweden)

    S. L. Rovin


    Full Text Available It is shown that introduction of rotary tilting furnaces can be a basis for considerable resources saving, lowering of power inputs, reduction of products cost for Byelorussian machine-building enterprises.

  3. Modular Distributed Concentrator for Solar Furnace Project (United States)

    National Aeronautics and Space Administration — This research proposes to develop a lightweight approach to achieving the high concentrations of solar energy needed for a solar furnace achieving temperatures of...

  4. Technology base for microgravity horticulture (United States)

    Sauer, R. L.; Magnuson, J. W.; Scruby, R. R.; Scheld, H. W.


    Advanced microgravity plant biology research and life support system development for the spacecraft environment are critically hampered by the lack of a technology base. This inadequacy stems primarily from the fact that microgravity results in a lack of convective currents and phase separation as compared to the one gravity environment. A program plan is being initiated to develop this technology base. This program will provide an iterative flight development effort that will be closely integrated with both basic science investigations and advanced life support system development efforts incorporating biological processes. The critical considerations include optimum illumination methods, root aeration, root and shoot support, and heat rejection and gas exchange in the plant canopy.

  5. Paired Straight Hearth Furnace - Transformational Ironmaking Process

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Wei-Kao [McMaster Univ., Hamilton, ON (Canada); Debski, Paul [Andritz Metals Inc.,Canonsburg, PA (United States)


    The U. S. steel industry has reduced its energy intensity per ton of steel shipped by 33% since 1990. However, further significant gains in energy efficiency will require the development of new, transformational iron and steelmaking processes. The Paired Straight Hearth Furnace (PSH) process is an emerging alternative high productivity, direct reduced iron (DRI) technology that may achieve very low fuel rates and has the potential to replace blast furnace ironmaking. The PSH furnace can operate independently or may be coupled with other melting technologies to produce liquid hot metal that is both similar to blast furnace iron and suitable as a feedstock for basic oxygen steelmaking furnaces. The PSH process uses non-metallurgical coal as a reductant to convert iron oxides such as iron ore and steelmaking by-product oxides to DRI pellets. In this process, a multi-layer, nominally 120mm tall bed of composite “green balls” made from oxide, coal and binder is built up and contained within a moving refractory hearth. The pellet bed absorbs radiant heat energy during exposure to the high temperature interior refractory surfaces of the PSH while generating a strongly reducing gas atmosphere in the bed that yields a highly metalized DRI product. The PSH concept has been well tested in static hearth experiments. A moving bed design is being developed. The process developers believe that if successful, the PSH process has the potential to replace blast furnaces and coke ovens at a fraction of the operating and capital cost while using about 30% less energy relative to current blast furnace technology. DRI output could also feed electric arc furnaces (EAFs) by displacing a portion of the scrap charge.

  6. Waste and dust utilisation in shaft furnaces


    Senk, D.; Babich, A.; Gudenau, H. W.


    Wastes and dusts from steel industry, non-ferrous metallurgy and other branches can be utilized e.g. in agglomeration processes (sintering, pelletizing or briquetting) and by injection into shaft furnaces. This paper deals with the second way. Combustion and reduction behaviour of iron- and carbon-rich metallurgical dusts and sludges containing lead, zinc and alkali as well as other wastes with and without pulverized coal (PC) has been studied when injecting into shaft furnaces. Following sha...

  7. Bulk Growth of 2-6 Crystals in the Microgravity Environment of USML-1 (United States)

    Gillies, Donald C.; Lehoczky, Sandor L.; Szofran, Frank R.; Larson, David J.; Su, Ching-Hua; Sha, Yi-Gao; Alexander, Helga A.


    The first United States Microgravity Laboratory Mission (USML- 1) flew in June 1992 on the Space Shuttle Columbia. An important part of this SpaceLab mission was the debut of the Crystal Growth Furnace (CGF). Of the seven samples grown in the furnace, three were bulk grown 2-6 compounds, two of a cadmium zinc telluride alloy, and one of a mercury zinc telluride alloy. Ground based results are presented, together with the results of computer simulated growths of these experimental conditions. Preliminary characterization results for the three USML-1 growth runs are also presented and the flight sample characteristics are compared to the equivalent ground truth samples. Of particular interest are the effect of the containment vessel on surface features, and especially on the nucleation, and the effect of the gravity vector on radial and axial compositional variations and stress and defect levels.

  8. Solar Convective Furnace for Metals Processing (United States)

    Patidar, Deepesh; Tiwari, Sheetanshu; Sharma, Piyush; Pardeshi, Ravindra; Chandra, Laltu; Shekhar, Rajiv


    Metals processing operations, primarily soaking, heat treatment, and melting of metals are energy-intensive processes using fossil fuels, either directly or indirectly as electricity, to operate furnaces at high temperatures. Use of concentrated solar energy as a source of heat could be a viable "green" option for industrial heat treatment furnaces. This paper introduces the concept of a solar convective furnace which utilizes hot air generated by an open volumetric air receiver (OVAR)-based solar tower technology. The potential for heating air above 1000°C exists. Air temperatures of 700°C have already been achieved in a 1.5-MWe volumetric air receiver demonstration plant. Efforts to retrofit an industrial aluminium soaking furnace for integration with a solar tower system are briefly described. The design and performance of an OVAR has been discussed. A strategy for designing a 1/15th-scale model of an industrial aluminium soaking furnace has been presented. Preliminary flow and thermal simulation results suggest the presence of recirculating flow in existing furnaces that could possibly result in non-uniform heating of the slabs. The multifarious uses of concentrated solar energy, for example in smelting, metals processing, and even fuel production, should enable it to overcome its cost disadvantage with respect to solar photovoltaics.

  9. Information modeling system for blast furnace control (United States)

    Spirin, N. A.; Gileva, L. Y.; Lavrov, V. V.


    Modern Iron & Steel Works as a rule are equipped with powerful distributed control systems (DCS) and databases. Implementation of DSC system solves the problem of storage, control, protection, entry, editing and retrieving of information as well as generation of required reporting data. The most advanced and promising approach is to use decision support information technologies based on a complex of mathematical models. The model decision support system for control of blast furnace smelting is designed and operated. The basis of the model system is a complex of mathematical models created using the principle of natural mathematical modeling. This principle provides for construction of mathematical models of two levels. The first level model is a basic state model which makes it possible to assess the vector of system parameters using field data and blast furnace operation results. It is also used to calculate the adjustment (adaptation) coefficients of the predictive block of the system. The second-level model is a predictive model designed to assess the design parameters of the blast furnace process when there are changes in melting conditions relative to its current state. Tasks for which software is developed are described. Characteristics of the main subsystems of the blast furnace process as an object of modeling and control - thermal state of the furnace, blast, gas dynamic and slag conditions of blast furnace smelting - are presented.

  10. The vacuum disconnector

    Energy Technology Data Exchange (ETDEWEB)

    Schellekens, H.


    After showing the extended experience of Holec with vacuum disconnectors, the difficulties encountered in developing the type SVS vacuum bottle are indicated. The implications of demands imposed on price and dimensions are translated into design features. The function and the design of the getter is explained to show how Holec guarantees a 20 year approved vacuum in the bottle. Finally, the results of switching tests are mentioned to explain the reliability and capability of the new disconnector. 12 figs.

  11. 17th International Microgravity Measurements Group Meeting (United States)

    DeLombard, Richard


    The Seventeenth International Microgravity Measurements Group (MGMG) meeting was held 24-26 March 1998 at the Ohio Aerospace Institute (OAI) in Brook Park, Ohio. This meeting focused on the transition of microgravity science research from the Shuttle, Mir, and free flyers to the International Space Station. The MGMG series of meetings are conducted by the Principal Investigator Microgravity Services project of the Microgravity Science Division at the NASA Lewis Research Center. The MGMG meetings provide a forum for the exchange of information and ideas about the microgravity environment and microgravity acceleration research in the Microgravity Research Program. The meeting had participation from investigators in all areas of microgravity research. The attendees included representatives from: NASA centers; National Space Development Agency of Japan; European Space Agency; Daimler Benz Aerospace AG; Deutsches Zentrum fuer Luft- und Raumfahrt; Centre National d'Etudes Spatiales; Canadian Space Agency, national research institutions; Universities in U.S., Italy, Germany, and Russia; and commercial companies in the U.S. and Russia. Several agencies presented summaries of the measurement, analysis, and characterization of the microgravity environment of the Shuttle, Mir, and sounding rockets over the past fifteen years. This extensive effort has laid a foundation for pursuing a similar course during future microgravity science experiment operations on the ISS. Future activities of microgravity environment characterization were discussed by several agencies who plan to operate on the ISS.

  12. Microgravity Smoldering Combustion Takes Flight (United States)


    The Microgravity Smoldering Combustion (MSC) experiment lifted off aboard the Space Shuttle Endeavour in September 1995 on the STS-69 mission. This experiment is part of series of studies focused on the smolder characteristics of porous, combustible materials in a microgravity environment. Smoldering is a nonflaming form of combustion that takes place in the interior of combustible materials. Common examples of smoldering are nonflaming embers, charcoal briquettes, and cigarettes. The objective of the study is to provide a better understanding of the controlling mechanisms of smoldering, both in microgravity and Earth gravity. As with other forms of combustion, gravity affects the availability of air and the transport of heat, and therefore, the rate of combustion. Results of the microgravity experiments will be compared with identical experiments carried out in Earth's gravity. They also will be used to verify present theories of smoldering combustion and will provide new insights into the process of smoldering combustion, enhancing our fundamental understanding of this frequently encountered combustion process and guiding improvement in fire safety practices.

  13. The economics of microgravity research. (United States)

    DiFrancesco, Jeanne M; Olson, John M


    In this introduction to the economics of microgravity research, DiFrancesco and Olson explore the existing landscape and begin to define the requirements for a robust, well-funded microgravity research environment. This work chronicles the history, the opportunities, and how the decisions made today will shape the future. The past 60 years have seen tremendous growth in the capabilities and resources available to conduct microgravity science. However, we are now at an inflection point for the future of humanity in space. A confluence of factors including the rise of commercialization, a shifting funding landscape, and a growing international presence in space exploration, and terrestrial research platforms are shaping the conditions for full-scale microgravity research programs. In this first discussion, the authors focus on the concepts of markets, tangible and intangible value, research pathways and their implications for investments in research projects, and the collateral platforms needed. The opportunities and implications for adopting new approaches to funding and market-making illuminate how decisions made today will affect the speed of advances the community will be able to achieve in the future.

  14. Burning in Outer Space: Microgravity (United States)

    Matkowsky, Bernard; Aldushin, Anatoly


    A better understanding of combustion can lead to significant technological advances, such as less polluting, more fuel-efficient vehicles. Unfortunately, gravity can interfere with the study of combustion. Gravity drags down gases that are cooler- and, therefore, denser-than heated gases. This movement mixes the fuel and the oxidizer substance that promotes burning. Because of this mixing, an observer cannot necessarily distinguish what is happening as a result of the natural combustion process and what is caused, by the pull of gravity. To remove this uncertainty, scientists can conduct experiments that simulate the negation of gravity through freefall. This condition is known as a microgravity environment. A micro-gravity experiment may take place in a chamber that is dropped down a hole or from a high-speed drop tower. The experiment also be conducted in an airplane or a rocket during freefall in a parabolic flight path. This method provides less than a minute of microgravity at most. An experiment that requires the prolonged absence of gravity may necessitate the use of an orbiting spacecraft as a venue. However, access to an orbital laboratory is difficult to acquire. High-end computing centers such as the NCCS can provide a practical alternative to operating in microgravity. Scientists can model phenomena such as combustion without gravitys observational interference. The study of microgravity combustion produces important benefits beyond increased observational accuracy. Certain valuable materials that are produced through combustion can be formed with a more uniform crystal structure-and, therefore, improved structural quality-when the pull of gravity is removed. Furthermore, understanding how fires propagate in the absence of gravity can improve fire safety aboard spacecraft.

  15. Microfabricated triggered vacuum switch (United States)

    Roesler, Alexander W [Tijeras, NM; Schare, Joshua M [Albuquerque, NM; Bunch, Kyle [Albuquerque, NM


    A microfabricated vacuum switch is disclosed which includes a substrate upon which an anode, cathode and trigger electrode are located. A cover is sealed over the substrate under vacuum to complete the vacuum switch. In some embodiments of the present invention, a metal cover can be used in place of the trigger electrode on the substrate. Materials used for the vacuum switch are compatible with high vacuum, relatively high temperature processing. These materials include molybdenum, niobium, copper, tungsten, aluminum and alloys thereof for the anode and cathode. Carbon in the form of graphitic carbon, a diamond-like material, or carbon nanotubes can be used in the trigger electrode. Channels can be optionally formed in the substrate to mitigate against surface breakdown.

  16. Insulation vacuum and beam vacuum overpressure release

    CERN Document Server

    Parma, V


    There is evidence that the incident of 19th September caused a high pressure build-up inside the cryostat insulation vacuum which the existing overpressure devices could not contain. As a result, high longitudinal forces acting on the insulation vacuum barriers developed and broke the floor and the floor fixations of the SSS with vacuum barriers. The consequent large longitudinal displacements of the SSS damaged chains of adjacent dipole cryo-magnets. Estimates of the helium mass flow and the pressure build- up experienced in the incident are presented together with the pressure build-up for an even more hazardous event, the Maximum Credible Incident (MCI). The strategy of limiting the maximum pressure by the installation of addition pressure relieve devices is presented and discussed. Both beam vacuum lines were ruptured during the incident in sector 3-4 giving rise to both mechanical damage and pollution of the system. The sequence, causes and effects of this damage will be briefly reviewed. We will then an...

  17. Industrial and process furnaces principles, design and operation

    CERN Document Server

    Jenkins, Barrie


    Furnaces sit at the core of all branches of manufacture and industry, so it is vital that these are designed and operated safely and effi-ciently. This reference provides all of the furnace theory needed to ensure that this can be executed successfully on an industrial scale. Industrial and Process Furnaces: Principles, 2nd Edition provides comprehensive coverage of all aspects of furnace operation and design, including topics essential for process engineers and operators to better understand furnaces. This includes: the combustion process and its control, furnace fuels, efficiency,

  18. High temperature aircraft research furnace facilities (United States)

    Smith, James E., Jr.; Cashon, John L.


    Focus is on the design, fabrication, and development of the High Temperature Aircraft Research Furnace Facilities (HTARFF). The HTARFF was developed to process electrically conductive materials with high melting points in a low gravity environment. The basic principle of operation is to accurately translate a high temperature arc-plasma gas front as it orbits around a cylindrical sample, thereby making it possible to precisely traverse the entire surface of a sample. The furnace utilizes the gas-tungsten-arc-welding (GTAW) process, also commonly referred to as Tungsten-Inert-Gas (TIG). The HTARFF was developed to further research efforts in the areas of directional solidification, float-zone processing, welding in a low-gravity environment, and segregation effects in metals. The furnace is intended for use aboard the NASA-JSC Reduced Gravity Program KC-135A Aircraft.

  19. Cogeneration from glass furnace waste heat recovery

    Energy Technology Data Exchange (ETDEWEB)

    Hnat, J.G.; Cutting, J.C.; Patten, J.S.


    In glass manufacturing 70% of the total energy utilized is consumed in the melting process. Three basic furnaces are in use: regenerative, recuperative, and direct fired design. The present paper focuses on secondary heat recovery from regenerative furnaces. A diagram of a typical regenerative furnace is given. Three recovery bottoming cycles were evaluated as part of a comparative systems analysis: steam Rankine Cycle (SRC), Organic Rankine Cycle (ORC), and pressurized Brayton cycle. Each cycle is defined and schematicized. The net power capabilities of the three different systems are summarized. Cost comparisons and payback period comparisons are made. Organic Rankine cycle provides the best opportunity for cogeneration for all the flue gas mass flow rates considered. With high temperatures, the Brayton cycle has the shortest payback period potential, but site-specific economics need to be considered.

  20. Fifth International Microgravity Combustion Workshop (United States)

    Sacksteder, Kurt (Compiler)


    This conference proceedings document is a compilation of 120 papers presented orally or as poster displays to the Fifth International Microgravity Combustion Workshop held in Cleveland, Ohio on May 18-20, 1999. The purpose of the workshop is to present and exchange research results from theoretical and experimental work in combustion science using the reduced-gravity environment as a research tool. The results are contributed by researchers funded by NASA throughout the United States at universities, industry and government research agencies, and by researchers from at least eight international partner countries that are also participating in the microgravity combustion science research discipline. These research results are intended for use by public and private sector organizations for academic purposes, for the development of technologies needed for the Human Exploration and Development of Space, and to improve Earth-bound combustion and fire-safety related technologies.

  1. Sixth International Microgravity Combustion Workshop (United States)

    Sacksteder, Kurt (Compiler)


    This conference proceedings document is a compilation of papers presented orally or as poster displays to the Sixth International Microgravity Combustion Workshop held in Cleveland, Ohio on May 22-24, 2001. The purpose of the workshop is to present and exchange research results from theoretical and experimental work in combustion science using the reduced-gravity environment as a research tool. The results are contributed by researchers funded by NASA throughout the United States at universities, industry and government research agencies, and by researchers from international partner countries that are also participating in the microgravity combustion science research discipline. These research results are intended for use by public and private sector organizations for academic purposes, for the development of technologies needed for Human Exploration and Development of Space, and to improve Earth-bound combustion and fire-safety related technologies.

  2. Microgravity Fluids for Biology, Workshop (United States)

    Griffin, DeVon; Kohl, Fred; Massa, Gioia D.; Motil, Brian; Parsons-Wingerter, Patricia; Quincy, Charles; Sato, Kevin; Singh, Bhim; Smith, Jeffrey D.; Wheeler, Raymond M.


    Microgravity Fluids for Biology represents an intersection of biology and fluid physics that present exciting research challenges to the Space Life and Physical Sciences Division. Solving and managing the transport processes and fluid mechanics in physiological and biological systems and processes are essential for future space exploration and colonization of space by humans. Adequate understanding of the underlying fluid physics and transport mechanisms will provide new, necessary insights and technologies for analyzing and designing biological systems critical to NASAs mission. To enable this mission, the fluid physics discipline needs to work to enhance the understanding of the influence of gravity on the scales and types of fluids (i.e., non-Newtonian) important to biology and life sciences. In turn, biomimetic, bio-inspired and synthetic biology applications based on physiology and biology can enrich the fluid mechanics and transport phenomena capabilities of the microgravity fluid physics community.

  3. Measure Guideline. High Efficiency Natural Gas Furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L. [Partnership for Advanced Residential Retrofit (PARR), Des Plaines, IL (United States); Rose, W. [Partnership for Advanced Residential Retrofit (PARR), Des Plaines, IL (United States)


    This measure guideline covers installation of high-efficiency gas furnaces, including: when to install a high-efficiency gas furnace as a retrofit measure; how to identify and address risks; and the steps to be used in the selection and installation process. The guideline is written for Building America practitioners and HVAC contractors and installers. It includes a compilation of information provided by manufacturers, researchers, and the Department of Energy as well as recent research results from the Partnership for Advanced Residential Retrofit (PARR) Building America team.

  4. Measure Guideline: High Efficiency Natural Gas Furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Brand, L.; Rose, W.


    This Measure Guideline covers installation of high-efficiency gas furnaces. Topics covered include when to install a high-efficiency gas furnace as a retrofit measure, how to identify and address risks, and the steps to be used in the selection and installation process. The guideline is written for Building America practitioners and HVAC contractors and installers. It includes a compilation of information provided by manufacturers, researchers, and the Department of Energy as well as recent research results from the Partnership for Advanced Residential Retrofit (PARR) Building America team.

  5. Waste and dust utilisation in shaft furnaces

    Directory of Open Access Journals (Sweden)

    Senk, D.


    Full Text Available Wastes and dusts from steel industry, non-ferrous metallurgy and other branches can be utilized e.g. in agglomeration processes (sintering, pelletizing or briquetting and by injection into shaft furnaces. This paper deals with the second way. Combustion and reduction behaviour of iron- and carbon-rich metallurgical dusts and sludges containing lead, zinc and alkali as well as other wastes with and without pulverized coal (PC has been studied when injecting into shaft furnaces. Following shaft furnaces have been examined: blast furnace, cupola furnace, OxiCup furnace and imperial-smelting furnace. Investigations have been done at laboratory and industrial scale. Some dusts and wastes under certain conditions can be not only reused but can also improve combustion efficiency at the tuyeres as well as furnace performance and productivity.

    Los residuos y polvos de filtro provenientes de la industria siderúrgica, de la obtención de metales no ferrosos y de otras industrias, pueden ser utilizados, por ejemplo, en procesos de aglomeración como sintetizado, peletizado o briqueteado. En su caso, estos pueden ser inyectados en los hornos de cuba. Este artículo se enfoca a la inyección de estos materiales en los hornos de cuba. El comportamiento de la combustión y reducción de los polvos ricos en hierro y carbono y también lodos que contienen plomo, zinc y compuestos alcalinos y otros residuos con o sin carbón pulverizado (CP fue examinado, cuando se inyectaron en hornos de cuba. Los siguientes hornos de cuba fueron examinados: Horno alto, cubilote, OxiCup y horno de cuba Imperial Smelting. Las investigaciones se llevaron a cabo a escala de laboratorio e industrial. Algunos residuos y polvos bajo ciertas condiciones, no sólo pueden ser reciclados, sino también mejoran la eficiencia de combustión en las toberas, la operación y productividad del horno.


    Directory of Open Access Journals (Sweden)

    S. L. Rovin


    Full Text Available It is shown that rotary furnaces and drying ovens are a perspective type of furnaces, allowing to solve a number of problems in conditions of flexible production and strong resources economy

  7. Vacuum spin squeezing (United States)

    Hu, Jiazhong; Chen, Wenlan; Vendeiro, Zachary; Urvoy, Alban; Braverman, Boris; Vuletić, Vladan


    We investigate the generation of entanglement (spin squeezing) in an optical-transition atomic clock through the coupling to an optical cavity in its vacuum state. We show that if each atom is prepared in a superposition of the ground state and a long-lived electronic excited state, and viewed as a spin-1/2 system, then the collective vacuum light shift entangles the atoms, resulting in a squeezed distribution of the ensemble collective spin, without any light applied. This scheme reveals that even an electromagnetic vacuum can constitute a useful resource for entanglement and quantum manipulation. By rotating the spin direction while coupling to the vacuum, the scheme can be extended to implement two-axis twisting resulting in stronger squeezing.

  8. Handbook of vacuum technology

    CERN Document Server


    This comprehensive, standard work has been updated to remain an important resource for all those needing detailed knowledge of the theory and applications of vacuum technology. With many numerical examples and illustrations to visualize the theoretical issues.

  9. Cold Vacuum Drying Facility (United States)

    Federal Laboratory Consortium — Located near the K-Basins (see K-Basins link) in Hanford's 100 Area is a facility called the Cold Vacuum Drying Facility (CVDF).Between 2000 and 2004, workers at the...

  10. Vacuum-assisted delivery (United States)

    ... the birth canal. The vacuum uses a soft plastic cup that attaches to the baby's head with suction. ... a numbing medicine placed in the vagina. The plastic cup will be placed on the baby's head. Then, ...

  11. Ultra high vacuum technology

    CERN Multimedia

    CERN. Geneva


    A short introduction for some basic facts and equations. Subsquently, discussion about: Building blocks of an ultrahigh vacuum system - Various types of pumps required to reach uhv and methods to reduce these effects - Outgassing phenomena induced by the presence of a particle beam and the most common methods to reduce these effects It will be given some practical examples from existing CERN accelerators and discuss the novel features of the future LHC vacuum system.

  12. Power vacuum tubes handbook

    CERN Document Server

    Whitaker, Jerry


    Providing examples of applications, Power Vacuum Tubes Handbook, Third Edition examines the underlying technology of each type of power vacuum tube device in common use today. The author presents basic principles, reports on new development efforts, and discusses implementation and maintenance considerations. Supporting mathematical equations and extensive technical illustrations and schematic diagrams help readers understand the material. Translate Principles into Specific Applications This one-stop reference is a hands-on guide for engineering personnel involved in the design, specification,

  13. A Planck Vacuum Cosmology

    Directory of Open Access Journals (Sweden)

    Daywitt W. C.


    Full Text Available Both the big-bang and the quasi-steady-state cosmologies originate in some type of Planck state. This paper presents a new cosmological theory based on the Planck- vacuum negative-energy state, a state consisting of a degenerate collection of negative- energy Planck particles. A heuristic look at the Einstein field equation provides a con- vincing argument that such a vacuum state could provide a theoretical explanation for the visible universe.


    Directory of Open Access Journals (Sweden)

    S. L. Rovin


    Full Text Available Rotary tilting furnace (RTF is a new type of fuel furnaces, that provide the most efficient heating and recycling of polydisperse materials. The paper describes results of the investigations on thermal processes in the RTF, movement of materials and non-isothermal gas flow during kiln rotary process. The investigations have been carried out while using physical and computer simulations and under actual operating conditions applying the pilot plant. Results of the research have served as a basis for development of recommendations on the RTF calculations and designing and they have been also used for constructional design of a rotary tilting furnace for heating and melting of cast iron chips, reduction smelting of steel mill scale, melting of aluminum scrap, melting of lead from battery scrap. These furnaces have a high thermal efficiency (~50 %, technological flexibility, high productivity and profitability. Proven technical solutions for recycling of ferrous and non-ferrous metals develop the use of RTF in the foundry and metallurgical industry as the main technological unit for creation of cost-effective small-tonnage recycling of metal waste generated at the plants. The research results open prospects for organization of its own production for high-quality charging material in Belarus in lieu of imported primary metal. The proposed technology makes it possible to solve environmental challenge pertaining to liquidation of multi-tonnage heaps of metal-containing wastes.

  15. Energy Saving Devices on Gas Furnaces. (United States)


    DEVICES FOR GAS FURNACES THOMAS E. BRISBANE ,o"’ P. B. SHEPHERD JOHNS-MANVILLE SALES CORPORATION RESEARCH & DEVELOPMENT CENTER KEN- CARYL RANCH, Mr. Thomas E. Brisbane under the direction of Dr. S. Karaki, Professor of Civil Engineering and Director, Solar Energy Application Laboratory. Mr

  16. Calibration procedure for fire resistance furnaces

    NARCIS (Netherlands)

    Twilt, L.; Leur, P.H.E. van de; Wickström, U.


    On behalf of CEN/TC 127 "Fire Safety in Buildings", a series of tests has been carried out to evaluate and complete the draft calibration procedure for fire resistance furnaces [4]. Fourteen laboratories in nine European countries participated in the test series, each carrying out one calibration

  17. Blast furnace hearth lining: post mortem analysis

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Bruno Vidal de; Vernilli Junior, Fernando, E-mail: [Universidade de Sao Paulo (USP), Lorena, SP (Brazil). Escola de Engenharia; Neves; Elton Silva; Silva, Sidiney Nascimento [Companhia Siderugica Nacional (CSN), Rio de Janeiro, RJ (Brazil)


    The main refractory lining of blast furnace hearth is composed by carbon blocks that operates in continuous contact with hot gases, liquid slag and hot metal, in temperatures above 1550 deg C for 24 hours a day. To fully understand the wear mechanism that acts in this refractory layer system it was performed a Post Mortem study during the last partial repair of this furnace. The samples were collected from different parts of the hearth lining and characterized using the following techniques: Bulk Density and Apparent Porosity, X-Ray Fluorescence, X-ray Diffraction, Scanning Electron Microscopy with Energy-dispersive X-Ray Spectroscopy. The results showed that the carbon blocks located at the opposite side of the blast furnace tap hole kept its main physicochemical characteristics preserved even after the production of 20x10{sup 6} ton of hot metal. However, the carbon blocks around the Tap Hole showed infiltration by hot metal and slag and it presents a severe deposition of zinc and sulfur over its carbon flakes. The presence of these elements is undesired because it reduces the physic-chemical stability of this refractory system. This deposition found in the carbon refractory is associated with impurities present in the both coke and the sinter feed used in this blast furnace in the last few years. (author)


    Directory of Open Access Journals (Sweden)

    S. L. Rovin


    Full Text Available The advantages of rotary furnaces, developed by specialists of GGTU named after P. O. Suhoj and UP «Tehnolit» for carrying out of ferric oxide recycling with regard to conditions of the Republic of Belarus, are described.

  19. Design and Testing of a Cupola Furnace for Micheal Okpara ...

    African Journals Online (AJOL)

    ... for the present study. It is thus recommended that this novelty design be used as a foundation for building bigger furnaces and for the sensitisation of students' awareness in foundry technology and practices. Keywords: furnace lining, refractory materials, critical radius of insulation, furnace fuel, heat transfer, cupola zones ...

  20. Thermal Analysis of an Industrial Furnace

    Directory of Open Access Journals (Sweden)

    Mirko Filipponi


    Full Text Available Industries, which are mainly responsible for high energy consumption, need to invest in research projects in order to develop new managing systems for rational energy use, and to tackle the devastating effects of climate change caused by human behavior. The study described in this paper concerns the forging industry, where the production processes generally start with the heating of steel in furnaces, and continue with other processes, such as heat treatments and different forms of machining. One of the most critical operations, in terms of energy loss, is the opening of the furnace doors for insertion and extraction operations. During this time, the temperature of the furnaces decreases by hundreds of degrees in a few minutes. Because the dispersed heat needs to be supplied again through the combustion of fuel, increasing the consumption of energy and the pollutant emissions, the evaluation of the amount of lost energy is crucial for the development of systems which can contain this loss. To perform this study, CFD simulation software was used. Results show that when the door opens, because of temperature and pressure differences between the furnace and the ambient air, turbulence is created. Results also show that the amount of energy lost for an opening of 10 min for radiation, convection and conduction is equal to 5606 MJ where convection is the main contributor, with 5020 MJ. The model created, after being validated, has been applied to perform other simulations, in order to improve the energy performance of the furnace. Results show that reducing the opening time of the door saves energy and limits pollutant emissions.

  1. Material properties of the F82H melted in an electric arc furnace

    Energy Technology Data Exchange (ETDEWEB)

    Sakasegawa, Hideo, E-mail: [Japan Atomic Energy Agency, Rokkasho, Aomori (Japan); Tanigawa, Hiroyasu [Japan Atomic Energy Agency, Rokkasho, Aomori (Japan); Kano, Sho; Abe, Hiroaki [Institute for Materials Research, Tohoku university, Sendai, Miyagi (Japan)


    Highlights: • We studied material properties of reduced activation ferritic/martensitic steel. • We melted F82H using a 20 tons electric arc furnace for the first time. • Mass effect likely affected material properties. • MX (M: Metal, C: Carbon and/or Nitrogen) precipitates mainly formed on grain and sub grain boundaries. - Abstract: Fusion DEMO reactor requires over 11,000 tons of reduced activation ferritic/martensitic steel. It is necessary to develop the manufacturing technology for fabricating such large-scale steel with appropriate mechanical properties. In this work, we focused fundamental mechanical properties and microstructures of F82H-BA12 heat which was melted using a 20 tons electric arc furnace followed by electroslag remelting process. Its raw material of iron was blast furnace iron, because the production volume of electrolytic iron which has been used in former heats, is limited. After melting and forging, this F82H-BA12 heat was heat-treated in four different conditions to consider their fluctuations and to optimize them, and tensile and Charpy impact tests were then performed. The result of these mechanical properties were comparable to those of former F82H heats less than 5 tons which were melted applying vacuum induction melting.

  2. Turning toys into microgravity machines (United States)

    Sumners, C.; Reiff, P.

    The Toys in Space program communicates the experience of being in space and ultimately living in space. In space, what would happen to a yo-yo's speed, a top's wobble, or your skill in playing soccer, throwing a boomerang or jumping rope? Discover how these toys and others have performed in microgravity and how these demonstrations can link children to the space program. On April 12, 1985 astronauts carried the first experiment package of miniature mechanical systems called toys into space. Since that time 54 toys have been demonstrated in microgravity. This summer, NASA and the Houston Museum of Natural Science have sponsored the first International Toys in Space project with sixteen toys chosen for their popularity and relevance around the world. This set of toys takes advantage of the larger Space Station by providing toys that take up more room - from two-person games of soccer, lacrosse, marbles, and hockey to a jump rope and several kinds of yoyos. Three earlier Toys in Space missions have shown that toys are ideal machines to demonstrate how gravity affects moving objects on the Earth's surface and how the motions of these objects change in microgravity. In this presentation, participants actually experiment with miniature versions of toys, predict their behavior on orbit, and watch the surprising results. Participants receive toy patterns to share with young people at home, around the world. The Toys in Space program scales for all ages. Young learners can use their observation and comparison skills while older students apply physics concepts to toy behaviors. Concepts demonstrated include all of Newton's Laws of Motion, gyroscopic stability, centripetal force, density, as well as conservation of linear and angular momentum.

  3. Review of European microgravity measurements (United States)

    Hamacher, Hans


    AA In a French/Russion cooperation, CNES developed a microgravity detection system for analyzing the Mir space station micro-g-environment for the first time. European efforts to characterize the microgravity (1/9) environment within a space laboratory began in the late seventies with the design of the First Spacelab Mission SL-1. Its Material Science Double Rack was the first payload element to carry its own tri-axial acceleration package. Even though incapable for any frequency analysis, the data provided a wealth of novel information for optimal experiment and hardware design and operations for missions to come. Theoretical investigations under ESA contract demonstrated the significance of the detailed knowledge of micro-g data for a thorough experiment analysis. They especially revealed the high sensitivity of numerous phenomena to low frequency acceleration. Accordingly, the payloads of the Spacelab missions D-1 and D-2 were furnished with state-of-the-art detection systems to ensure frequency analysis between 0.1 and 100 Hz. The Microgravity Measurement Assembly (MMA) of D-2 was a centralized system comprising fixed installed as well as mobile tri-axial packages showing real-time data processing and transmission to ground. ESA's free flyer EURECA carried a system for continuous measurement over the entire mission. All EURECA subsystems and experimental facilities had to meet tough requirements defining the upper acceleration limits. In a French/Russion cooperation, CNES developed a mi crogravity detection system for analyzing the Mir space station micro-g-environment for the first time. An approach to get access to low frequency acceleration between 0 and 0.02 Hz will be realized by QSAM (Quasi-steady Acceleration Measurement) on IML-2, complementary to the NASA system Spacelab Acceleration Measurement System SAMS. A second flight of QSAM is planned for the Russian free flyer FOTON.


    Directory of Open Access Journals (Sweden)

    Abdullah BÜYÜKYILDIZ


    Full Text Available In this study, a furnace which is used for observation of environments under high temperature, and also used for manufacturing of glasses which are resisted to high temperature has been designed and implemented. Automation of this system has been done by using PLC. Operating parameters of furnace such as materials entering, the furnace, the local temperature control of furnace, cooling control and materials outing have been sensed with Hall Effect Sensor. Furthermore, the observation of parameters of furnace on screen has been provided with SCADA software. Obtained products have been shown the system works successfully.

  5. Computational Material Processing in Microgravity (United States)


    Working with Professor David Matthiesen at Case Western Reserve University (CWRU) a computer model of the DPIMS (Diffusion Processes in Molten Semiconductors) space experiment was developed that is able to predict the thermal field, flow field and concentration profile within a molten germanium capillary under both ground-based and microgravity conditions as illustrated. These models are coupled with a novel nonlinear statistical methodology for estimating the diffusion coefficient from measured concentration values after a given time that yields a more accurate estimate than traditional methods. This code was integrated into a web-based application that has become a standard tool used by engineers in the Materials Science Department at CWRU.

  6. Microgravity effects on pathogenicity of bacteria

    Directory of Open Access Journals (Sweden)

    Ya-juan WANG


    Full Text Available Microgravity is one of the important environmental conditions during spaceflight. A series of studies have shown that many kinds of bacteria could be detected in space station and space shuttle. Space environment or simulated microgravity may throw a certain influence on those opportunistic pathogens and lead to some changes on their virulence, biofilm formation and drug tolerance. The mechanism of bacteria response to space environment or simulated microgravity has not been defined. However, the conserved RNA-binding protein Hfq has been identified as a likely global regulator involved in the bacteria response to this environment. In addition, microgravity effects on bacterial pathogenicity may threaten astronauts' health. The present paper will focus on microgravity-induced alterations of pathogenicity and relative mechanism in various opportunistic pathogens.

  7. Effect of simulated microgravity on Aspergillus niger (United States)

    Pratap, Jeffrey J.


    A rotating bioreactor was developed to simulate microgravity and its influence was studied on fungal growth. The reactor was designed to simulate microgravity using 'free fall' principle, which creates an apparent weightlessness for a brief period of time. In this experiment, a sealed vertically rotating tube is the reactor in which the cells are grown. For the first time vertically rotating tubes were used to obtain 'free fall' thereby simulating microgravity. Simulated microgravity served significant in the alteration of growth and productivity of Aspergillus niger, a common soil fungi. Two other sets of similar cultures were maintained as still and shake control cultures to compare with the growth and productivity of cells in rotating culture. It was found increased growth and productivity occurred in simulated microgravity. Since this experiment involves growth of cells in a liquid medium, the fluidic effects must also be studied which is a limitation.

  8. A Geology Sampling System for Microgravity Bodies (United States)

    Hood, Anthony; Naids, Adam


    Human exploration of microgravity bodies is being investigated as a precursor to a Mars surface mission. Asteroids, comets, dwarf planets, and the moons of Mars all fall into this microgravity category and some are been discussed as potential mission targets. Obtaining geological samples for return to Earth will be a major objective for any mission to a microgravity body. Currently the knowledge base for geology sampling in microgravity is in its infancy. Humans interacting with non-engineered surfaces in microgravity environment pose unique challenges. In preparation for such missions a team at the NASA Johnson Space Center has been working to gain experience on how to safely obtain numerous sample types in such an environment. This paper describes the type of samples the science community is interested in, highlights notable prototype work, and discusses an integrated geology sampling solution.

  9. Vacuum induced photoresist outgassing (United States)

    Waterman, Justin; Mbanaso, Chimaobi; Denbeaux, Gregory


    In order to continue the trend toward smaller feature sizes in lithography, new methods of lithography will be needed. A likely method for printing features 32 nm and smaller is extreme ultraviolet (EUV) lithography. EUV allows for features to be printed that are smaller than the current methods can achieve. However, outgassing of the photoresist is a concern for EUV lithography. The outgassed components can lead to contamination of the optics, degrading the reflectivity and hence lowering throughput of the exposure tools. Outgassing due to EUV exposure has been investigated by many groups. However, there were no complete investigations available of vacuum induced outgassing. In this paper, several methods were employed to investigate the outgassing due to vacuum. It was found that the vacuum induced outgassing outgassed a similar number of molecules as the outgassing due to EUV exposure. Furthermore, almost all of the outgassing was completed after about two minutes in vacuum. To mitigate the potential concern of outgassing due to vacuum causing contamination of optics, this work shows that photoresist coated silicon wafers only require about two minutes of pumping prior to insertion near the optics within EUV lithography tools.

  10. Development of vacuum continuous casting technology for uranium

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y.S.; Kim, C. K.; Kim, K. H.; Lee, D. B.; Kim, J. D.; Jang, S. J.; Ahn, H. S.; Shin, Y. J


    The spent fuel disposal process of new dry storage concept has been developed in KAERI, in which the uranium metal abstracted by Li-reduction of spent fuel will be formed to long rods and then the rods will be arranged uniformly in canister. The objective of this study is to review the feasibility of applying the continuous casting method to cast a long rod with modifying the vacuum high-frequency induction furnace to vacuum continuous casting system, which was normally used to cast the uranium. The results are as follows. With the nozzle size of 3mm and the withdrawal speed of 3.5 mm/sec, the length of 160mm, diameter of 30 mm continuous casting uranium bar was successfully cast. This result shows there might be a possibility of continuous casting of uranium and helps the design and fabrication of new continuous casting equipment.

  11. Behavior of sustained high-current arcs on molten-alloy electrodes during vacuum consumable-arc remelting (United States)

    Zanner, F. J.; Bertram, L. A.

    Vacuum consumable arc remelting is a casting process carried out in a vacuum with the aim of remelting the consumable electrode in such a way that the new ingot has improved chemical and physical homogeneity. The power which causes the melting is supplied by a vacuum arc burning between the electrodes. In order to determine the furnace partitions of electrical power and current, experiments were conducted on molten faced round electrodes. The quasi-steady melt rate was determined for both horizontally opposed 15 cm dia. Ni electrodes and for vertically suspended 40 cm dia. Inconel 718 electrodes.

  12. Improving Vacuum Cleaners (United States)


    Under a Space Act Agreement between the Kirby company and Lewis Research Center, NASA technology was applied to a commercial vacuum cleaner product line. Kirby engineers were interested in advanced operational concepts, such as particle flow behavior and vibration, critical factors to improve vacuum cleaner performance. An evaluation of the company 1994 home care system, the Kirby G4, led to the refinement of the new G5 and future models. Under the cooperative agreement, Kirby had access to Lewis' holography equipment, which added insight into how long a vacuum cleaner fan would perform, as well as advanced computer software that can simulate the flow of air through fans. The collaboration resulted in several successes including fan blade redesign and continuing dialogue on how to improve air-flow traits in various nozzle designs.

  13. Vacuum Arc Ion Sources

    CERN Document Server

    Brown, I.


    The vacuum arc ion source has evolved into a more or less standard laboratory tool for the production of high-current beams of metal ions, and is now used in a number of different embodiments at many laboratories around the world. Applications include primarily ion implantation for material surface modification research, and good performance has been obtained for the injection of high-current beams of heavy-metal ions, in particular uranium, into particle accelerators. As the use of the source has grown, so also have the operational characteristics been improved in a variety of different ways. Here we review the principles, design, and performance of vacuum arc ion sources.

  14. Baryogenesis in false vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, Yuta [KEK Theory Center, IPNS, KEK, Tsukuba, Ibaraki (Japan); Yamada, Masatoshi [Kanazawa University, Institute for Theoretical Physics, Kanazawa (Japan)


    The null result in the LHC may indicate that the standard model is not drastically modified up to very high scales, such as the GUT/string scale. Having this in the mind, we suggest a novel leptogenesis scenario realized in the false vacuum of the Higgs field. If the Higgs field develops a large vacuum expectation value in the early universe, a lepton number violating process is enhanced, which we use for baryogenesis. To demonstrate the scenario, several models are discussed. For example, we show that the observed baryon asymmetry is successfully generated in the standard model with higher-dimensional operators. (orig.)

  15. A rotating quantum vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Lorenci, V.A. de; Svaiter, N.F. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)


    It was investigated which mapping has to be used to compare measurements made in a rotating frame to those made in an inertial frame. Using a non-Galilean coordinate transformation, the creation-annihilation operators of a massive scalar field in the rotating frame are not the same as those of an inertial observer. This leads to a new vacuum state(a rotating vacuum) which is a superposition of positive and negative frequency Minkowski particles. Polarization effects in circular accelerators in the proper frame of the electron making a connection with the inertial frame point of view were analysed. 65 refs.

  16. Handbook of vacuum physics

    CERN Document Server


    Handbook of Vacuum Physics, Volume 3: Technology is a handbook of vacuum physics, with emphasis on the properties of miscellaneous materials such as mica, oils, greases, waxes, and rubber. Accurate modern tables of physical constants, properties of materials, laboratory techniques, and properties of commercial pumps, gauges, and leak detectors are presented. This volume is comprised of 12 chapters and begins with a discussion on pump oils, divided into rotary pump oils and vapor pump oils. The next chapter deals with the properties and applications of greases, including outgassing and vapor pr


    Directory of Open Access Journals (Sweden)

    S. L. Rovin


    Full Text Available The article presents the results of studies of gas movement and heat and mass transfer processes in the rotary tilting furnace (RTF at the heat treatment of disperse materials. The study was performed through computer modeling using software packages ANSYS CFX and Solid Works Flow Simulation. The results were used to design RTF with different capacity and application and helped to improve their technical and economic characteristics.

  18. Technology handbook of vacuum physics

    CERN Document Server

    Beck, A H


    Handbook of Vacuum Physics, Volume 3: Technology is part of a series of publications that presents articles featuring the whole spectrum of vacuum physics. This particular volume presents materials that deal with technology concerns in vacuum mechanics. The first material talks about the utilization of ceramic materials in the construction of vacuum devices. The next paper details the application of vacuum physics in soldering and brazing process. The last article deals with the utilization of vacuum technology in high frequency heating. The book will be of great use to professionals involved

  19. LEP Vacuum Chamber

    CERN Multimedia


    This is a cut-out of a LEP vacuum chamber for dipole magnets showing the beam channel and the pumping channel with the getter (NEG) strip and its insulating supports. A water pipe connected to the cooling channel can also be seen at the back.The lead radiation shield lining is also shown. See also 8305563X.

  20. The vacuum strikes back

    CERN Multimedia


    "Modern physics has shown that the vacuum, previously thought of as a stated of total nothingness, is really a seething background of virtual particles springing in and out of eixstence until they can seize enough energy to materialize as "real" particles." (1,5 page)

  1. LEP vacuum chamber, prototype

    CERN Multimedia

    CERN PhotoLab


    Final prototype for the LEP vacuum chamber, see 8305170 for more details. Here we see the strips of the NEG pump, providing "distributed pumping". The strips are made from a Zr-Ti-Fe alloy. By passing an electrical current, they were heated to 700 deg C.

  2. ISR vacuum system

    CERN Multimedia

    CERN PhotoLab


    Some of the most important components of the vacuum system are shown. At the left, the rectangular box is a sputter-ion pump inside its bake-out oven. The assembly in the centre includes a sector valve, three roughing valves, a turbomolecular pump, a rotary backing pump and auxiliary equipment. At the right, the small elbow houses a Bayard-

  3. Vacuum-induction melting, refining, and casting of uranium and its alloys

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, R J


    The vacuum-induction melting (VIM), refining, and casting of uranium and its alloys are discussed. Emphasis is placed on historical development, VIM equipment, crucible and mold design, furnace atmospheres, melting parameters, impurity pickup, ingot quality, and economics. The VIM procedures used to produce high-purity, high-quality sound ingots at the US Department of Energy Rocky Flats Plant are discussed in detail.

  4. Reduce Air Infiltration in Furnaces (English/Chinese) (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)


    Chinese translation of the Reduce Air Infiltration in Furnaces fact sheet. Provides suggestions on how to improve furnace energy efficiency. Fuel-fired furnaces discharge combustion products through a stack or a chimney. Hot furnace gases are less dense and more buoyant than ambient air, so they rise, creating a differential pressure between the top and the bottom of the furnace. This differential, known as thermal head, is the source of a natural draft or negative pressure in furnaces and boilers. A well-designed furnace (or boiler) is built to avoid air leakage into the furnace or leakage of flue gases from the furnace to the ambient. However, with time, most furnaces develop cracks or openings around doors, joints, and hearth seals. These openings (leaks) usually appear small compared with the overall dimensions of the furnace, so they are often ignored. The negative pressure created by the natural draft (or use of an induced-draft fan) in a furnace draws cold air through the openings (leaks) and into the furnace. The cold air becomes heated to the furnace exhaust gas temperature and then exits through the flue system, wasting valuable fuel. It might also cause excessive oxidation of metals or other materials in the furnaces. The heat loss due to cold air leakage resulting from the natural draft can be estimated if you know four major parameters: (1) The furnace or flue gas temperature; (2) The vertical distance H between the opening (leak) and the point where the exhaust gases leave the furnace and its flue system (if the leak is along a vertical surface, H will be an average value); (3) The area of the leak, in square inches; and (4) The amount of operating time the furnace spends at negative pressure. Secondary parameters that affect the amount of air leakage include these: (1) The furnace firing rate; (2) The flue gas velocity through the stack or the stack cross-section area; (3) The burner operating conditions (e.g., excess air, combustion air temperature

  5. Interface Shape and Growth Rate Analysis of Se/GaAs Bulk Crystals Grown in the NASA Crystal Growth Furnace (CGF) (United States)

    Bly, J. M.; Kaforey, M. L.; Matthiesen, D. H.; Chait, A.


    Selenium-doped gallium arsenide, Se/GaAs, bulk crystals have been grown on earth using NASA's crystal growth furnace (CGF) in preparation for microgravity experimentation on the USML-2 spacelab mission. Peltier cooling pulses of 50 ms duration, 2040 A magnitude, and 0.0033 Hz frequency were used to successfully demark the melt-solid interface at known times during the crystal growth process. Post-growth characterization included interface shape measurement, growth rate calculation, and growth rate transient determinations. It was found that the interface shapes were always slightly concave into the solid. The curvature of the seeding interfaces was typically 1.5 mm for the 15 mm diameter samples. This was in agreement with the predicted interface shapes and positions relative to the furnace determined using a numerical model of the sample/ampoule/cartridge assembly (SACA).

  6. Tritium handling in vacuum systems

    Energy Technology Data Exchange (ETDEWEB)

    Gill, J.T. [Monsanto Research Corp., Miamisburg, OH (United States). Mound Facility; Coffin, D.O. [Los Alamos National Lab., NM (United States)


    This report provides a course in Tritium handling in vacuum systems. Topics presented are: Properties of Tritium; Tritium compatibility of materials; Tritium-compatible vacuum equipment; and Tritium waste treatment.

  7. Microgravity Workstation and Restraint Evaluations (United States)

    Chmielewski, C.; Whitmore, M.; Mount, F.


    Confined workstations, where the operator has limited visibility and physical access to the work area, may cause prolonged periods of unnatural posture. Impacts on performance, in terms of fatigue and posture, may occur especially if the task is tedious and repetitive or requires static muscle loading. The glovebox design is a good example of the confined workstation concept. Within the scope of the 'Microgravity Workstation and Restraint Evaluation' project, funded by the NASA Headquarters Life Sciences Division, it was proposed to conduct a series of evaluations in ground, KC-135 and Shuttle environments to investigate the human factors issues concerning confined/unique workstations, such as gloveboxes, and also including crew restraint requirements. As part of the proposed integrated evaluations, two Shuttle Detailed Supplementary Objectives (DSOs) were manifested; one on Space Transportation System (STS)-90 and one on STS-88. The DSO on STS-90 evaluated use of the General Purpose Workstation (GPWS). The STS-88 mission was planned to evaluate a restraint system at the Remote Manipulator System (RMS). In addition, KC- 1 35 flights were conducted to investigate user/workstation/restraint integration for long-duration microgravity use. The scope of these evaluations included workstations and restraints to be utilized in the ISS environment, but also incorporated other workstations/ restraints in an attempt to provide findings/requirements with broader applications across multiple programs (e.g., Shuttle, ISS, and future Lunar-Mars programs). In addition, a comprehensive electronic questionnaire has been prepared and is under review by the Astronaut Office which will compile crewmembers' lessons learned information concerning glovebox and restraint use following their missions. These evaluations were intended to be complementary and were coordinated with hardware developers, users (crewmembers), and researchers. This report is intended to provide a summary of the

  8. Effect of Microgravity on Mammalian Lymphocytes (United States)

    Banerjee, H.; Blackshear, M.; Mahaffey, K.; Khan, A. A.; Delucas, L.


    The effect of microgravity on mammalian system is an important and interesting topic for scientific investigation, since NASA s objective is to send manned flights to planets like Mars and eventual human colonization. The Astronauts will be exposed to microgravity environment for a long duration of time during these flights. Our objective of research is to conduct in vitro studies for the effect of microgravity on mammalian immune system and nervous system. We did our preliminary investigations by exposing mammalian lymphocytes and astrocyte cells to a microgravity simulator cell bioreactor designed by NASA and manufactured at Synthecon, Inc. (USA).Our initial results showed no significant change in cytokine expression in these cells up to a time period of 120 hours exposure. Our future experiments will involve exposure for a longer period of time.

  9. Advanced Microgravity Compatible, Integrated Laundry System Project (United States)

    National Aeronautics and Space Administration — An Advanced Microgravity Compatible, Integrated laundry System (AMCILS) is proposed that uses a two phase water / water vapor system to allow good agitation of...

  10. BIM LAU-PE: Seedlings in Microgravity (United States)

    Gass, S.; Pennese, R.; Chapuis, D.; Dainesi, P.; Nebuloni, S.; Garcia, M.; Oriol, A.


    The effect of gravity on plant roots is an intensive subject of research. Sounding rockets represent a costeffective platform to study this effect under microgravity conditions. As part of the upcoming MASER 13 sounding rocket campaign, two experiments on Arabidopsis thaliana seedlings have been devised: GRAMAT and SPARC. These experiments are aimed at studying (1) the genes that are specifically switched on or off during microgravity, and (2) the position of auxin-transporting proteins during microgravity. To perform these experiments, RUAG Space Switzerland site of Nyon, in collaboration with the Swedish Space Corporation (SSC) and the University of Freiburg, has developed the BIM LAU-PE (Biolology In Microgravity Late Access Unit Plant Experiment). In the following an overview of the BIM LAU-PE design is presented, highlighting specific module design features and verifications performed. A particular emphasis is placed on the parabolic flight experiments, including results of the micro-g injection system validation.

  11. Melting and casting of alloys in a solar furnace

    Energy Technology Data Exchange (ETDEWEB)

    Suresh, D. (Indian Inst. of Science, Bangalore, India); Rohatgi, P.K.


    A feasibility study conducted using a small working model of a solar furnace is reported in which the melting and casting of various alloys was tested. The prototype furnace had either a spun copper or aluminum hemispherical concentrator, and was manually tracked. A later self-tracking version consisted of a paraboloidal cofiguration fabricated from a wire mesh antenna covered with aluminized polyester. The experimental results show that a simple and inexpensive solar furnace could be commercialized in the near future. (SPH)

  12. Pellet reduction properties under different blast furnace operating conditions


    Leimalm, Ulrika


    One of the aims of modern blast furnace (BF) ironmaking is to reduce coke consumption. One way is to increase the injection of reduction agents, such as pulverized coal. An increase in pulverized coal injection rate (PCR) will affect the blast furnace process and the conditions for iron oxide reduction. Changes in PCR influence the composition of the ascending gases and the in-furnace temperature isotherms. The performed tests involve full-scale, pilot and laboratory investigations. Raw mater...

  13. Microgravity flight testing of a laboratory robot (United States)

    Hinman, Elaine M.


    A review is given of the conditions and preparations for studying the performance of a robotic laboratory manipulator under microgravity conditions and by means of dynamic simulations. The robotic arm is fitted with accelerometers, incorporated into a materials-transfer workcell, and flown on a microgravity simulator. A software package based on the Lagrangian form of the equations of motion is used for dynamic analysis and control-systems development of the arm.

  14. Biological Kraft Chemical Recycle for Augmentation of Recovery Furnace Capacity

    Energy Technology Data Exchange (ETDEWEB)

    Stuart E. Strand


    The chemicals used in pulping of wood by the kraft process are recycled in the mill in the recovery furnace, which oxidizes organics while simultaneously reducing sulfate to sulfide. The recovery furnace is central to the economical operation of kraft pulp mills, but it also causes problems. The total pulp production of many mills is limited by the recovery furnace capacity, which cannot easily be increased. The furnace is one of the largest sources of air pollution (as reduced sulfur compounds) in the kraft pulp mill.

  15. Slag wool manufacturing from blast furnace slag

    Directory of Open Access Journals (Sweden)

    Володимир Петрович Руських


    Full Text Available Slag wool is the most expensive and valuable product of blast furnace slag processing. Slag wool is in great demand nowadays. The article highlights the factors influencing the mineral wool quality: chemical composition that determines the acidity of the module, the temperature of the molten slag and the required slag jet thickness consistency. Mineral wool is produced by blowing air or steam into a jet of molten slag. As a result of it the slag crushes into droplets stretching. The resulting wool contains 5% slag and 95% air. The quality of the obtained slag wool depends on the module acidity of the slag. The blast furnace slags of «Ilyich iron and steel works of Mariupol» and «Azovstal iron & steel works» are the main (short slags – they give short fibers. To obtain high-quality long fiber wool it is necessary to add admixtures into basic blast furnace slag to reduce its basicity. As a result of the fuel and energy rising prices and the necessity to reduce the slag wool cost it is necessary to develop a new technology with fiery-liquid slag, with the removal of iron compounds and sulphur from the melts and the introduction of corrective additives to improve the quality of slag wool. Good thermal conductivity (about 0,03 kcal/m∙h∙°C and other indicators (resistance, volume weight make it possible to use the materials from slag wool (pads, rigid and semi-rigid plates as heat and sound insulating materials

  16. Carbon Tubular Morphologies in Blast Furnace Coke

    Directory of Open Access Journals (Sweden)

    Stanislav S. Gornostayev


    Full Text Available The paper reports on the first occurrence of microscale carbon tubular morphologies (CMTs in a blast furnace (BF coke. The CMTs were probably formed as a result of the conversion of solid disordered carbon via liquid phase metal particles involving a gas phase containing a substantial amount of N2 and O2. The presence of CMTs may lie behind the generation of the smallest fraction of fines in BF exhaust dust. If the amount of CMTs present in the BF exhausts gases at any particular metallurgical site proves to be substantial, it could become a subject of environmental concern.





    In today’s industrial scenario huge losses/wastage occur in the manufacturing shop floor and foundry industries. The efficiency of any foundry largely depends on the efficiency of the melting process amulti-step operation where the metal is heated, treated, alloyed, and transported into die or mold cavities to form a casting. In this paper we represents the performance testing and analysis of Cupola Furnace, and reduces the problems occurs to give the best results. Our main focus in this work...

  18. Nonperturbative QED vacuum birefringence (United States)

    Denisov, V. I.; Dolgaya, E. E.; Sokolov, V. A.


    In this paper we represent nonperturbative calculation for one-loop Quantum Electrodynamics (QED) vacuum birefringence in presence of strong magnetic field. The dispersion relations for electromagnetic wave propagating in strong magnetic field point to retention of vacuum birefringence even in case when the field strength greatly exceeds Sauter-Schwinger limit. This gives a possibility to extend some predictions of perturbative QED such as electromagnetic waves delay in pulsars neighbourhood or wave polarization state changing (tested in PVLAS) to arbitrary magnetic field values. Such expansion is especially important in astrophysics because magnetic fields of some pulsars and magnetars greatly exceed quantum magnetic field limit, so the estimates of perturbative QED effects in this case require clarification.


    Directory of Open Access Journals (Sweden)

    Zaid A. Abdulrahman


    Full Text Available Simulated column performance curves were constructed for existing paraffin separation vacuum distillation column in LAB plant (Arab Detergent Company/Baiji-Iraq. The variables considered in this study are the thermodynamic model option, top vacuum pressure, top and bottom temperatures, feed temperature, feed composition & reflux ratio. Also simulated columns profiles for the temperature, vapor & liquid flow rates composition were constructed. Four different thermodynamic model options (SRK, TSRK, PR, and ESSO were used, affecting the results within 1-25% variation for the most cases.The simulated results show that about 2% to 8 % of paraffin (C10, C11, C12, & C13 present at the bottom stream which may cause a problem in the LAB plant. The major variations were noticed for the top temperature & the  paraffin weight fractions at bottom section with top vacuum pressure. The bottom temperature above 240 oC is not recommended because the total bottom flow rate decreases sharply, where as  the weight fraction of paraffins decrease slightly. The study gives evidence about a successful simulation with CHEMCAD

  20. STARDUST - A simulation experiment of cosmic dust analogues production in microgravity conditions (United States)

    Ferguson, Frank T.; Lilleleht, L. U.; Nuth, J.; Stephens, J. R.; Bussoletti, E.; Carotenuto, L.; Colangeli, L.; Dell'aversana, P.; Mele, F.; Mennella, V.


    The condensation of solid materials from the vapor phase is important in several scientific fields such as chemical vapor deposition, air pollution and the formation of refractory cosmic dust around stars. Conventional studies of refractory grain formation, using high temperature furnace and shock tube techniques, are restricted to short time scales and suffer from buoyancy induced convection that limit their accuracy. In order to simulate more accurately the condensation of refractory grains near stars and to investigate the advantages of performing condensation studies in microgravity conditions, an experimental investigation was undertaken. This work reports the experimental equipment currently used. The results from the first flight series and particle aggregation modelling efforts are presented briefly.

  1. Glass Furnace Combustion and Melting Research Facility.

    Energy Technology Data Exchange (ETDEWEB)

    Connors, John J. (PPG Industries, Inc., Pittsburgh, PA); McConnell, John F. (JFM Consulting, Inc., Pittsburgh, PA); Henry, Vincent I. (Henry Technology Solutions, LLC, Ann Arbor, MI); MacDonald, Blake A.; Gallagher, Robert J.; Field, William B. (Lilja Corp., Livermore, CA); Walsh, Peter M.; Simmons, Michael C. (Lilja Corp., Livermore, CA); Adams, Michael E. (Lilja Corp., Rochester, NY); Leadbetter, James M. (A.C. Leadbetter and Son, Inc., Toledo, OH); Tomasewski, Jack W. (A.C. Leadbetter and Son, Inc., Toledo, OH); Operacz, Walter J. (A.C. Leadbetter and Son, Inc., Toledo, OH); Houf, William G.; Davis, James W. (A.C. Leadbetter and Son, Inc., Toledo, OH); Marvin, Bart G. (A.C. Leadbetter and Son, Inc., Toledo, OH); Gunner, Bruce E. (A.C. Leadbetter and Son, Inc., Toledo, OH); Farrell, Rick G. (A.C. Leadbetter and Son, Inc., Toledo, OH); Bivins, David P. (PPG Industries, Inc., Pittsburgh, PA); Curtis, Warren (PPG Industries, Inc., Pittsburgh, PA); Harris, James E. (PPG Industries, Inc., Pittsburgh, PA)


    The need for a Combustion and Melting Research Facility focused on the solution of glass manufacturing problems common to all segments of the glass industry was given high priority in the earliest version of the Glass Industry Technology Roadmap (Eisenhauer et al., 1997). Visteon Glass Systems and, later, PPG Industries proposed to meet this requirement, in partnership with the DOE/OIT Glass Program and Sandia National Laboratories, by designing and building a research furnace equipped with state-of-the-art diagnostics in the DOE Combustion Research Facility located at the Sandia site in Livermore, CA. Input on the configuration and objectives of the facility was sought from the entire industry by a variety of routes: (1) through a survey distributed to industry leaders by GMIC, (2) by conducting an open workshop following the OIT Glass Industry Project Review in September 1999, (3) from discussions with numerous glass engineers, scientists, and executives, and (4) during visits to glass manufacturing plants and research centers. The recommendations from industry were that the melting tank be made large enough to reproduce the essential processes and features of industrial furnaces yet flexible enough to be operated in as many as possible of the configurations found in industry as well as in ways never before attempted in practice. Realization of these objectives, while still providing access to the glass bath and combustion space for optical diagnostics and measurements using conventional probes, was the principal challenge in the development of the tank furnace design. The present report describes a facility having the requirements identified as important by members of the glass industry and equipped to do the work that the industry recommended should be the focus of research. The intent is that the laboratory would be available to U.S. glass manufacturers for collaboration with Sandia scientists and engineers on both precompetitive basic research and the

  2. Arsenic immobilization of Teniente furnace dust

    Energy Technology Data Exchange (ETDEWEB)

    Ichimura, R. [Japan Oil, Gas, and Metals National Corp., Kawasaki (Japan); Tateiwa, H. [Mitsui Mining and Smelting Co. Ltd., Saitama (Japan); Almendares, C. [Centro de Investigacion Minera y Metalurgica, Santiago (Chile); Sanchez, G. [CODELCO, Santiago (Chile). Division Ventanas


    A 5-year joint Japanese-Chilean project to modify the treatment of furnace dust from a converter in Chile producing harmful amounts of arsenic and lead was described. A pilot plant was constructed to evaluate the method's commercialization potential. Flue dust was recovered by a dust collector installed to capture suspended dust generated by the smelting furnace. Arsenic content was approximately 15 per cent. Ninety per cent of the arsenic was then liquidated to lixivia and dissolved by leaching flue dust with sulphuric acid. The leaching rate decreased when flue dust had a high content of residual sulfide ore. A flotation device was then incorporated in the treatment process in order to increase the copper recovery rate. A solvent recovery process was then adopted to recover the copper and zinc contained in the solution after the arsenic recovery. An economic evaluation of the process indicated that efforts should be made to improve the efficiency of the dust treatment method. 5 refs., 6 tabs., 10 figs.

  3. Estimation of slagging in furnaces; Kuonaavuuden ennustaminen kivihiilen poelypoltossa

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, T.; Jaeaeskelaeinen, K.; Oeini, J.; Koskiahde, A.; Jokiniemi, J.; Pyykkoenen, J. [Imatran Voima Oy, Vantaa (Finland)


    Understanding and estimation of slagging in furnaces is essential in the design of new power plants with high steam values or in modifications like low-NO{sub x} retrofits in existing furnaces. Major slagging yields poor efficiency, difficult operation and high maintenance costs of the plant. The aim of the project is to develop a computational model for slagging in pulverized coal combustion. The model is based on Computer Controlled Scanning Electron Microscopy (CCSEM) analysis of mineral composition of the coal and physical models for behaviour of minerals inside a furnace. The analyzed mineral particles are classified to five composition classes and distributed to calculational coal particles if internal minerals of coal. The calculational coal particles and the external minerals are traced in the furnace to find out the behaviour of minerals inside the furnace. If the particle tracing indicates that the particle hits the heat transfer surface of the furnace the viscosity of the particle is determined to see if particle is sticky. The model will be implemented to 3D computational fluid dynamics based furnace simulation environment Ardemus which predicts the fluid dynamics, heat transfer and combustion in a furnace. (orig.)

  4. Heat pipes and use of heat pipes in furnace exhaust (United States)

    Polcyn, Adam D.


    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  5. Utilization of steel melting electric arc furnace slag for development ...

    Indian Academy of Sciences (India)


    Steel melting through electric arc furnace route is gaining popularity due to its many advantages, but generates a new waste, electric arc furnace slag, which is getting accumulated and land/mine filling and road construction are the only ... is a key factor, in such constructions as breakwater blocks, foundations, shoring walls, ...

  6. Development of a cylindrical gas-fired furnace for reycling ...

    African Journals Online (AJOL)

    This study presents the development of a cylindrical gas-fired furnace, which could be used for recycling aluminum in small-scale foundries in Nigeria. The crucible, combustion chamber, suspension shaft and bearings were appropriately sized. The furnace chamber was 410 mm high and 510 mm diameter and had a ...

  7. Artificial neural networks in predicting current in electric arc furnaces (United States)

    Panoiu, M.; Panoiu, C.; Iordan, A.; Ghiormez, L.


    The paper presents a study of the possibility of using artificial neural networks for the prediction of the current and the voltage of Electric Arc Furnaces. Multi-layer perceptron and radial based functions Artificial Neural Networks implemented in Matlab were used. The study is based on measured data items from an Electric Arc Furnace in an industrial plant in Romania.


    DEFF Research Database (Denmark)

    Jacobsen, P.; Dahi, Elian


    A low-tech furnace for charring of raw bone using char coal is developed and tested. The furnace consists of a standard oil drum, fitted with simple materials as available in every market in small towns in developing counties. 80 kg of raw bone and 6 kg of charcoal are used for production of 50 k...

  9. Design and Construction of Oil Fired Compact Crucible Furnace ...

    African Journals Online (AJOL)

    As a prelude to necessary industrialization, foundries are springing up in various parts of Nigeria and most of these foundries rely on oil fired furnaces in their operation. This study is aimed at developing an oil fired crucible furnace from locally sourced materials for foundries in Nigeria. In our design, a new system of fuel ...


    Directory of Open Access Journals (Sweden)

    S. L. Rovin


    Full Text Available This article describes motion and heat and mass transfer in the layer of dispersed material in a rotary furnace. Presents the results of a comprehensive study of these processes, including pilot studies, computer modeling and simulation, which allow to optimize the design and process parameters of rotary furnaces.

  11. Method of operating a centrifugal plasma arc furnace (United States)

    Kujawa, S.T.; Battleson, D.M.; Rademacher, E.L. Jr.; Cashell, P.V.; Filius, K.D.; Flannery, P.A.; Whitworth, C.G.


    A centrifugal plasma arc furnace is used to vitrify contaminated soils and other waste materials. An assessment of the characteristics of the waste is performed prior to introducing the waste into the furnace. Based on the assessment, a predetermined amount of iron is added to each batch of waste. The waste is melted in an oxidizing atmosphere into a slag. The added iron is oxidized into Fe{sub 3}O{sub 4}. Time of exposure to oxygen is controlled so that the iron does not oxidize into Fe{sub 2}O{sub 3}. Slag in the furnace remains relatively non-viscous and consequently it pours out of the furnace readily. Cooled and solidified slag produced by the furnace is very resistant to groundwater leaching. The slag can be safely buried in the earth without fear of contaminating groundwater. 3 figs.

  12. Considerations for Scale-Up of Ferronickel Electric Smelting Furnaces (United States)

    Hundermark, R. J.; Nelson, L. R.


    In ferronickel smelting, the selective carbothermic reduction of calcined nickel laterite ores in large electric furnaces yields a crude ferronickel product. The optimal process for nickel laterite smelting requires a fine balance between the metallurgical requirements of the process (feed composition, nickel recovery, energy consumption, product quality) and the capabilities of the feeding, tapping and off-gas systems, and especially of the furnace crucible and electrical system. The scale-up of nickel laterite smelting operations over the last 50 years has seen a tenfold increase in furnace power input. Furnace operations within the industry are examined to identify common trends and some new metrics are proposed which incorporate the combination of electrode power densities and the impact of alloy nickel grade on gas generation rates, and hence local electrode gas fluxes, which may impact on future scale-up of ferronickel furnaces.

  13. Description of a Furnace for the Creation of Anisotropic Porous Metals

    Energy Technology Data Exchange (ETDEWEB)

    Gutsch, Thomas; Miszkiel, Mark; Schmale, David T.


    A furnace has been built for the purpose of producing anisotropic porous metals through solid-gas eutectic solidification. This process allows control of continuously formed anisotropic pores in metals and was discovered at the State Metallurgical Academic' University in Dnepropetrovsk Ukraine. The process incorporates hydrogen gas within the metal as it solidifies from the molten state. Metals which do not form hydrides, including iron, nickel, aluminum, copper and others can be formed in this manner. The furnace is housed within a ~.64 meter³ (30 ft³) ASME code stamped cylindrical stainless steel vacuum/pressure vessel. The vessel is a water chilled vertical cylinder with removable covers at the top and bottom. It can be evacuated to 20 mTorr or pressurized to 5.5 MPa (800 psi). A charge of 2700 cc (167 in³) of molten metal can be melted in a crucible in the upper portion within a watercooled 30 cm (12 in.) ID induction coil. A 175 kW Inductotherm power source energizes the coil. Vertical actuation of a ceramic stopper rod allows the molten metal to be tapped into a solidification mold beneath the melting crucible. The cylindrical mold rests on a water cooled copper base inducing directional solidification from the bottom. Mixtures of hydrogen and argon gases are introduced during the process. The system is remotely controlled and located in a structure with frangible walls specially designed for possible ambient pressure excursions as a result of equipment failure. This paper includes a general description of the furnace and operating procedure and a detailed description of the control, monitoring and interlock systems.

  14. The vacuum platform (United States)

    McNab, A.


    This paper describes GridPP’s Vacuum Platform for managing virtual machines (VMs), which has been used to run production workloads for WLCG and other HEP experiments. The platform provides a uniform interface between VMs and the sites they run at, whether the site is organised as an Infrastructure-as-a-Service cloud system such as OpenStack, or an Infrastructure-as-a-Client system such as Vac. The paper describes our experience in using this platform, in developing and operating VM lifecycle managers Vac and Vcycle, and in interacting with VMs provided by LHCb, ATLAS, ALICE, CMS, and the GridPP DIRAC service to run production workloads.

  15. Vacuum ultraviolet spectroscopy I

    CERN Document Server

    Samson, James A; Lucatorto, Thomas


    This volume is for practitioners, experimentalists, and graduate students in applied physics, particularly in the fields of atomic and molecular physics, who work with vacuum ultraviolet applications and are in need of choosing the best type of modern instrumentation. It provides first-hand knowledge of the state-of-the-art equipment sources and gives technical information on how to use it, along with a broad reference bibliography.Key Features* Aimed at experimentalists who are in need of choosing the best type of modern instrumentation in this applied field* Contains a detailed chapter on la

  16. R&D ERL: Vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Mapes, M.; Smart, L.; Weiss, D.; Steszyn, A.; Todd, R.


    The ERL Vacuum systems are depicted in a figure. ERL has eight vacuum volumes with various sets of requirements. A summary of vacuum related requirements is provided in a table. Five of the eight volumes comprise the electron beamline. They are the 5-cell Superconducting RF Cavity, Superconducting e-gun, injection, loop and beam dump. Two vacuum regions are the individual cryostats insulating the 5-cell Superconducting RF Cavity and the Superconducting e-gun structures. The last ERL vacuum volume not shown in the schematic is the laser transport line. The beamline vacuum regions are separated by electropneumatic gate valves. The beam dump is common with loop beamline but is considered a separate volume due to geometry and requirements. Vacuum in the 5-cell SRF cavity is maintained in the {approx}10{sup -9} torr range at room temperature by two 20 l/s ion pumps and in the e-gun SRF cavity by one 60 l/s ion pump. Vacuum in the SRF cavities operated at 2{sup o}K is reduced to low 10{sup -11} torr via cryopumping of the cavity walls. The cathode of the e-gun must be protected from poisoning, which can occur if vacuum adjacent to the e-gun in the injection line exceeds 10-11 torr range in the injection warm beamline near the e-gun exit. The vacuum requirements for beam operation in the loop and beam dump are 10-9 torr range. The beamlines are evacuated from atmospheric pressure to high vacuum level with a particulate free, oil free turbomolecular pumping cart. 25 l/s shielded ion pumps distributed throughout the beamlines maintain the vacuum requirement. Due to the more demanding vacuum requirement of the injection beamline proximate to the e-gun, a vacuum bakeout of the injection beamline is required. In addition, two 200 l/s diode ion pumps and supplemental pumping provided by titanium sublimation pumps are installed in the injection line just beyond the exit of the e-gun. Due to expected gas load a similar pumping arrangement is planned for the beam dump. The

  17. Ukrainian Program for Material Science in Microgravity (United States)

    Fedorov, Oleg

    Ukrainian Program for Material Sciences in Microgravity O.P. Fedorov, Space Research Insti-tute of NASU -NSAU, Kyiv, The aim of the report is to present previous and current approach of Ukrainian research society to the prospect of material sciences in microgravity. This approach is based on analysis of Ukrainian program of research in microgravity, preparation of Russian -Ukrainian experiments on Russian segment of ISS and development of new Ukrainian strategy of space activity for the years 2010-2030. Two parts of issues are discussed: (i) the evolution of our views on the priorities in microgravity research (ii) current experiments under preparation and important ground-based results. item1 The concept of "space industrialization" and relevant efforts in Soviet and post -Soviet Ukrainian research institutions are reviewed. The main topics are: melt supercooling, crystal growing, testing of materials, electric welding and study of near-Earth environment. The anticipated and current results are compared. item 2. The main experiments in the framework of Ukrainian-Russian Research Program for Russian Segment of ISS are reviewed. Flight installations under development and ground-based results of the experiments on directional solidification, heat pipes, tribological testing, biocorrosion study is presented. Ground-based experiments and theoretical study of directional solidification of transparent alloys are reviewed as well as preparation of MORPHOS installation for study of succinonitrile -acetone in microgravity.

  18. EPS (Electric Particulate Suspension) Microgravity Technology Provides NASA with New Tools (United States)

    Colver, Gerald M.; Greene, Nate; Xu, Hua


    The Electric Particulate Suspension is a fire safety ignition test system being developed at Iowa State University with NASA support for evaluating combustion properties of powders, powder-gas mixtures, and pure gases in microgravity and gravitational atmospheres (quenching distance, ignition energy, flammability limits). A separate application is the use of EPS technology to control heat transfer in vacuum and space environment enclosures. In combustion testing, ignitable powders (aluminum, magnesium) are introduced in the EPS test cell and ignited by spark, while the addition of inert particles act as quenching media. As a combustion research tool, the EPS method has potential as a benchmark design for quenching powder flames that would provide NASA with a new fire safety standard for powder ignition testing. The EPS method also supports combustion modeling by providing accurate measurement of flame-quenching distance as an important parameter in laminar flame theory since it is closely related to characteristic flame thickness and flame structure. In heat transfer applications, inert powder suspensions (copper, steel) driven by electric fields regulate heat flow between adjacent surfaces enclosures both in vacuum (or gas) and microgravity. This simple E-field control can be particularly useful in space environments where physical separation is a requirement between heat exchange surfaces.

  19. Of vacuum and gas

    CERN Multimedia

    Katarina Anthony


    A new LHCb programme is delving into uncharted waters for the LHC: exploring how protons interact with noble gases inside the machine pipe. While, at first glance, it may sound risky for the overall quality of the vacuum in the machine, the procedure is safe and potentially very rich in rewards. The results could uncover the high-energy helium-proton cross-section (with all the implications thereof), explore new boundaries of the quark-gluon plasma and much more.   As the beam passes through LHCb, interactions with neon gas allow the experiment to measure the full beam profile. In this diagram, beam 1 (blue) and beam 2 (red) are measured by the surrounding VELO detector. It all begins with luminosity. In 2011, LHCb set out to further improve its notoriously precise measurements of the beam profile, using the so-called Beam-Gas Imaging (BGI) method. BGI does exactly what it says on the tin: a small amount of gas is inserted into the vacuum, increasing the rate of collisions around the interaction ...

  20. LHC vacuum system

    CERN Document Server

    Gröbner, Oswald


    The Large Hadron Collider (LHC) project, now in the advanced construction phase at CERN, comprises two proton storage rings with colliding beams of 7-TeV energy. The machine is housed in the existing LEP tunnel with a circumference of 26.7 km and requires a bending magnetic field of 8.4 T with 14-m long superconducting magnets. The beam vacuum chambers comprise the inner 'cold bore' walls of the magnets. These magnets operate at 1.9 K, and thus serve as very good cryo-pumps. In order to reduce the cryogenic power consumption, both the heat load from synchrotron radiation emitted by the proton beams and the resistive power dissipation by the beam image currents have to be absorbed on a 'beam screen', which operates between 5 and 20 K and is inserted inside the vacuum chamber. The design of this beam screen represents a technological challenge in view of the numerous and often conflicting requirements and the very tight mechanical tolerances imposed. The synchrotron radiation produces strong outgassing from the...

  1. Vacuum science, technology, and applications

    CERN Document Server

    Naik, Pramod K


    Vacuum plays an important role in science and technology. The study of interaction of charged particles, neutrals and radiation with each other and with solid surfaces requires a vacuum environment for reliable investigations. Vacuum has contributed immensely to advancements made in nuclear science, space, metallurgy, electrical/electronic technology, chemical engineering, transportation, robotics and many other fields. This book is intended to assist students, scientists, technicians and engineers to understand the basics of vacuum science and technology for application in their projects. The fundamental theories, concepts, devices, applications, and key inventions are discussed.

  2. Secondary metabolism in simulated microgravity (United States)

    Demain, A. L.; Fang, A.


    We have studied microbial secondary metabolism in a simulated microgravity (SMG) environment provided by NASA rotating-wall bioreactors (RWBs). These reactors were designed to simulate some aspects of actual microgravity that occur in space. Growth and product formation were observed in SMG in all cases studied, i.e., Bacillus brevis produced gramicidin S (GS), Streptomyces clavuligerus made beta-lactam antibiotics, Streptomyces hygroscopicus produced rapamycin, and Escherichia coli produced microcin B17 (MccB17). Of these processes, only GS production was unaffected by SMG; production of the other three products was inhibited. This was determined by comparison with performance in an RWB positioned in a different mode to provide a normal gravity (NG) environment. Carbon source repression by glycerol of the GS process, as observed in shaken flasks, was not observed in the RWBs, whether operated in the SMG or NG mode. The same phenomenon occurred in the case of MccB17 production, with respect to glucose repression. Thus, the negative effects of carbon source on GS and beta-lactam formation are presumably dependent on shear, turbulence, and/or vessel geometry, but not on gravity. Stimulatory effects of phosphate and the precursor L-lysine on beta-lactam antibiotic production, as observed in flasks, also occurred in SMG. An almost complete shift in the localization of produced MccB17 from cells to extracellular medium was observed when E. coli was grown in the RWB under SMG or NG. If a plastic bead was placed in the RWB, accumulation became cellular, as it is in shaken flasks, indicating that sheer stress favors a cellular location. In the case of rapamycin, the same type of shift was observed, but it was less dramatic, i.e., growth in the RWB under SMG shifted the distribution of produced rapamycin from 2/3 cellular:1/3 extracellular to 1/3 cellular:2/3 extracellular. Stress has been shown to induce or promote secondary metabolism in a number of other microbial

  3. Microgravity Drill and Anchor System (United States)

    Parness, Aaron; Frost, Matthew A.; King, Jonathan P.


    This work is a method to drill into a rock surface regardless of the gravitational field or orientation. The required weight-on-bit (WOB) is supplied by a self-contained anchoring mechanism. The system includes a rotary percussive coring drill, forming a complete sampling instrument usable by robot or human. This method of in situ sample acquisition using micro - spine anchoring technology enables several NASA mission concepts not currently possible with existing technology, including sampling from consolidated rock on asteroids, providing a bolt network for astronauts visiting a near-Earth asteroid, and sampling from the ceilings or vertical walls of lava tubes and cliff faces on Mars. One of the most fundamental parameters of drilling is the WOB; essentially, the load applied to the bit that allows it to cut, creating a reaction force normal to the surface. In every drilling application, there is a minimum WOB that must be maintained for the system to function properly. In microgravity (asteroids and comets), even a small WOB could not be supported conventionally by the weight of the robot or astronaut. An anchoring mechanism would be needed to resist the reactions, or the robot or astronaut would push themselves off the surface and into space. The ability of the system to anchor itself to a surface creates potential applications that reach beyond use in low gravity. The use of these anchoring mechanisms as end effectors on climbing robots has the potential of vastly expanding the scope of what is considered accessible terrain. Further, because the drill is supported by its own anchor rather than by a robotic arm, the workspace is not constrained by the reach of such an arm. Yet, if the drill is on a robotic arm, it has the benefit of not reflecting the forces of drilling back to the arm s joints. Combining the drill with the anchoring feet will create a highly mobile, highly stable, and highly reliable system. The drilling system s anchor uses hundreds of

  4. Torrefied biomasses in a drop tube furnace to evaluate their utility in blast furnaces. (United States)

    Chen, Wei-Hsin; Du, Shan-Wen; Tsai, Chien-Hsiung; Wang, Zhen-Yu


    Torrefaction and burning characteristics of bamboo, oil palm, rice husk, bagasse, and Madagascar almond were studied and compared with a high-volatile bituminous coal using a drop tube furnace to evaluate the potential of biomass consumed in blast furnaces. Torrefaction at 250 and 300°C for 1h duration was carried out. Analysis using the ash tracer method indicated that the extent of atomic carbon reduction in the biomasses was less than that of atomic hydrogen and oxygen. Torrefaction also lowered the sulfur content in bamboo and oil palm over 33%. An examination of the R-factor and burnout of the samples suggests that more volatiles were released and a higher burnout was achieved with raw and torrefied biomasses at 250°C than at 300°C; however, torrefaction at 300°C is a feasible operating condition to transform biomass into a solid fuel resembling a high-volatile bituminous coal used for blast furnaces. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Kennedy Educate to Innovate (KETI) Microgravity Powerpoint Presentation (United States)


    The purpose of this presentation is to define and explain microgravity and show how microgravity can help students learn about the phenomena of the world. The presentation is designed to provide teachers of science, technology, engineering, and mathematics at many levels with a foundation in microgravity science and applications.

  6. Neurology of microgravity and space travel (United States)

    Fujii, M. D.; Patten, B. M.


    Exposure to microgravity and space travel produce several neurologic changes, including SAS, ataxia, postural disturbances, perceptual illusions, neuromuscular weakness, and fatigue. Inflight SAS, perceptual illusions, and ocular changes are of more importance. After landing, however, ataxia, perceptual illusions, neuromuscular weakness, and fatigue play greater roles in astronaut health and readaptation to a terrestrial environment. Cardiovascular adjustments to microgravity, bone demineralization, and possible decompression sickness and excessive radiation exposure contribute further to medical problems of astronauts in space. A better understanding of the mechanisms by which microgravity adversely affects the nervous system and more effective treatments will provide healthier, happier, and longer stays in space on the space station Freedom and during the mission to Mars.

  7. Aerodynamic and engineering design of a 1.5 s high quality microgravity drop tower facility (United States)

    Belser, Valentin; Breuninger, Jakob; Reilly, Matthew; Laufer, René; Dropmann, Michael; Herdrich, Georg; Hyde, Truell; Röser, Hans-Peter; Fasoulas, Stefanos


    Microgravity experiments are essential for research in space science, biology, fluid mechanics, combustion, and material sciences. One way to conduct microgravity experiments on Earth is by using drop tower facilities. These facilities combine a high quality of microgravity, adequate payload masses and have the advantage of virtually unlimited repeatability under same experimental conditions, at a low cost. In a collaboration between the Institute of Space Systems (IRS) at the University of Stuttgart and Baylor University (BU) in Waco, Texas, a new drop tower is currently under development at the Center for Astrophysics, Space Physics and Engineering Research (CASPER). The design parameters of the drop tower ask for at least 1.5 s in free fall duration while providing a quality of at least 10-5 g. Previously, this quality has only been achieved in vacuum drop tower facilities where the capsule experiences virtually zero aerodynamic drag during its free fall. Since this design comes at high costs, a different drop tower design concept, which does not require an evacuated drop shaft, was chosen. It features a dual-capsule system in which the experiment capsule is shielded from aerodynamic forces by surrounding it with a drag shield during the drop. As no other dual-capsule drop tower has been able to achieve a quality as good as or better than 10-5 g previous work optimized the design with an aerodynamic perspective by using computational fluid dynamics (CFD) simulations to determine the ideal shape and size of the outer capsule and to specify the aerodynamically crucial dimensions for the overall system. Experiments later demonstrated that the required quality of microgravity can be met with the proposed design. The main focus of this paper is the mechanical realization of the capsule as well as the development and layout of the surrounding components, such as the release mechanism, the deceleration device and the drop shaft. Because the drop tower facility is a

  8. Technology Thresholds for Microgravity: Status and Prospects (United States)

    Noever, D. A.


    The technological and economic thresholds for microgravity space research are estimated in materials science and biotechnology. In the 1990s, the improvement of materials processing has been identified as a national scientific priority, particularly for stimulating entrepreneurship. The substantial US investment at stake in these critical technologies includes six broad categories: aerospace, transportation, health care, information, energy, and the environment. Microgravity space research addresses key technologies in each area. The viability of selected space-related industries is critically evaluated and a market share philosophy is developed, namely that incremental improvements in a large markets efficiency is a tangible reward from space-based research.

  9. Microgravity Materials Science Conference 2000. Volume 1 (United States)

    Ramachandran, Narayanan (Editor); Bennett, Nancy (Editor); McCauley, Dannah (Editor); Murphy, Karen (Editor); Poindexter, Samantha (Editor)


    This is Volume 1 of 3 of the 2000 Microgravity Material Science Conference that was held June 6-8 at the Von Braun Center, Huntsville, Alabama. It was organized by the Microgravity Materials Science Discipline Working Group, sponsored by the Microgravity Research Division (MRD) at NASA Headquarters, and hosted by NASA Marshall Space Flight Center and the Alliance for Microgravity Materials Science and Applications (AMMSA). It was the fourth NASA conference of this type in the microgravity materials science discipline. The microgravity science program sponsored approx. 200 investigators, all of whom made oral or poster presentations at this conference. In addition, posters and exhibits covering NASA microgravity facilities, advanced technology development projects sponsored by the NASA Microgravity Research Division at NASA Headquarters, and commercial interests were exhibited. The purpose of the conference was to inform the materials science community of research opportunities in reduced gravity and to highlight the Spring 2001 release of the NASA Research Announcement (NRA) to solicit proposals for future investigations. It also served to review the current research and activities in materials science, to discuss the envisioned long-term goals. and to highlight new crosscutting research areas of particular interest to MRD. The conference was aimed at materials science researchers from academia, industry, and government. A workshop on in situ resource utilization (ISRU) was held in conjunction with the conference with the goal of evaluating and prioritizing processing issues in Lunar and Martian type environments. The workshop participation included invited speakers and investigators currently funded in the material science program under the Human Exploration and Development of Space (HEDS) initiative. The conference featured a plenary session every day with an invited speaker that was followed by three parallel breakout sessions in subdisciplines. Attendance was

  10. Microgravity Materials Science Conference 2000. Volume 2 (United States)

    Ramachandran, Narayanan (Editor); Bennett, Nancy (Editor); McCauley, Dannah (Editor); Murphy, Karen (Editor); Poindexter, Samantha (Editor)


    This is Volume 2 of 3 of the 2000 Microgravity Materials Science Conference that was held June 6-8 at the Von Braun Center, Huntsville, Alabama. It was organized by the Microgravity Materials Science Discipline Working Group, sponsored by the Microgravity Research Division (MRD) at NASA Headquarters, and hosted by NASA Marshall Space Flight Center and the Alliance for Microgravity Materials Science and Applications (AMMSA). It was the fourth NASA conference of this type in the Microgravity materials science discipline. The microgravity science program sponsored approx. 200 investigators, all of whom made oral or poster presentations at this conference- In addition, posters and exhibits covering NASA microgravity facilities, advanced technology development projects sponsored by the NASA Microgravity Research Division at NASA Headquarters, and commercial interests were exhibited. The purpose of the conference %%,its to inform the materials science community of research opportunities in reduced gravity and to highlight the Spring 2001 release of the NASA Research Announcement (NRA) to solicit proposals for future investigations. It also served to review the current research and activities in material,, science, to discuss the envisioned long-term goals. and to highlight new crosscutting research areas of particular interest to MRD. The conference was aimed at materials science researchers from academia, industry, and government. A workshop on in situ resource utilization (ISRU) was held in conjunction with the conference with the goal of evaluating and prioritizing processing issues in Lunar and Martian type environments. The workshop participation included invited speakers and investigators currently funded in the material science program under the Human Exploration and Development of Space (HEDS) initiative. The conference featured a plenary session every day with an invited speaker that was followed by three parallel breakout sessions in subdisciplines. Attendance

  11. Microgravity Materials Science Conference 2000. Volume 3 (United States)

    Ramachandran, Narayanan; Bennett, Nancy; McCauley, Dannah; Murphy, Karen; Poindexter, Samantha


    This is Volume 3 of 3 of the 2000 Microgravity Materials Science Conference that was held June 6-8 at the Von Braun Center, Huntsville, Alabama. It was organized by the Microgravity Materials Science Discipline Working Group, sponsored by the Microgravity Research Division (MRD) at NASA Headquarters, and hosted by NASA Marshall Space Flight Center and the Alliance for Microgravity Materials Science and Applications (AMMSA). It was the fourth NASA conference of this type in the Microgravity materials science discipline. The microgravity science program sponsored 200 investigators, all of whom made oral or poster presentations at this conference- In addition, posters and exhibits covering NASA microgravity facilities, advanced technology development projects sponsored by the NASA Microgravity Research Division at NASA Headquarters, and commercial interests were exhibited. The purpose of the conference was to inform the materials science community of research opportunities in reduced gravity and to highlight the Spring 2001 release of the NASA Research Announcement (NRA) to solicit proposals for future investigations. It also served to review the current research and activities in material,, science, to discuss the envisioned long-term goals. and to highlight new crosscutting research areas of particular interest to MRD. The conference was aimed at materials science researchers from academia, industry, and government. A workshop on in situ resource utilization (ISRU) was held in conjunction with the conference with the goal of evaluating and prioritizing processing issues in Lunar and Martian type environments. The workshop participation included invited speakers and investigators currently funded in the material science program under the Human Exploration and Development of Space (HEDS) initiative. The conference featured a plenary session every day with an invited speaker that was followed by three parallel breakout sessions in subdisciplines. Attendance was close

  12. The Influence of Microgravity on Plants (United States)

    Levine, Howard G.


    This slide presentation reviews the studies and the use of plants in various space exploration scenarios. The current state of research on plant growth in microgravity is reviewed, with several questions that require research for answers to assist in our fundamental understanding of the influence of microgravity and the space environment on plant growth. These questions are posed to future Principal Investigators and Payload Developers, attending the meeting, in part, to inform them of NASA's interest in proposals for research on the International Space Station.

  13. An update on blast furnace granular coal injection

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D.G. [Bethlehem Steel Corp., Burns Harbor, IN (United States); Strayer, T.J.; Bouman, R.W. [Bethlehem Steel Corp., PA (United States)


    A blast furnace coal injection system has been constructed and is being used on the furnace at the Burns Harbor Division of Bethlehem Steel. The injection system was designed to deliver both granular (coarse) and pulverized (fine) coal. Construction was completed on schedule in early 1995. Coal injection rates on the two Burns Harbor furnaces were increased throughout 1995 and was over 200 lbs/ton on C furnace in September. The injection rate on C furnace reached 270 lbs/ton by mid-1996. A comparison of high volatile and low volatile coals as injectants shows that low volatile coal replaces more coke and results in a better blast furnace operation. The replacement ratio with low volatile coal is 0.96 lbs coke per pound of coal. A major conclusion of the work to date is that granular coal injection performs very well in large blast furnaces. Future testing will include a processed sub-bituminous coal, a high ash coal and a direct comparison of granular versus pulverized coal injection.

  14. Resistance heated melting and holding furnaces for aluminium casting

    Energy Technology Data Exchange (ETDEWEB)

    Atkins, R.


    Resistance heated furnaces are ideal for holding and melter/holding applications in aluminium foundries. Electric resistance bale out furnaces can be fed with liquid metal and used as holding furnaces. They are also capable of melting at rates of 150/160 kg per hour at 720C. Improvements in element material have resulted in designs capable of maximum melt rates approaching that of fuel fired furnaces. A well proven design is available utilising semi-embedded elements in 2 versions to provide minimum energy consumption at lowest capital cost. A recent development is element panels produced by a new technique and using different materials which means the elements can be fully enclosed without any loss of performance. For larger aluminium pressure diecasting with substantial bulk melting facilities, insulated box furnaces have proved to be very attractive for holding metal at the diecasting machine. Electric immersion furnaces are also beginning to be used. These have the advantage of high efficiency and improved temperature control. The article concludes by discussing the implementation of energy management systems in conjunction with electric melting, and the introduction of electric ladles for keeping aluminium hot when transferring it from bulk furnaces.

  15. Vacuum energy sequestering and graviton loops


    Kaloper, Nemanja; Padilla, Antonio


    We recently formulated a local mechanism of vacuum energy sequester. This mechanism automatically removes all matter loop contributions to vacuum energy from the stress energy tensor which sources the curvature. Here we adapt the local vacuum energy sequestering mechanism to also cancel all the vacuum energy loops involving virtual gravitons, in addition to the vacuum energy generated by matter fields alone.


    Price, G.W.


    A protector device is described for use in controlling the pressure within a cyclotron. In particular, an electrical circuit functions to actuate a vacuum pump when a predetermined low pressure is reached and disconnect the pump when the pressure increases abcve a certain value. The principal feature of the control circuit lies in the use of a voltage divider network at the input to a relay control tube comprising two parallel, adjustable resistances wherein one resistor is switched into the circuit when the relay connects the pump to a power source. With this arrangement the relay is energized at one input level received from a sensing element within the cyclotron chamber and is de-energized when a second input level, representing the higher pressure limit, is reached.

  17. Abdominal intrauterine vacuum aspiration. (United States)

    Tjalma, W A A


    Evaluating and "cleaning" of the uterine cavity is probably the most performed operation in women. It is done for several reasons: abortion, evaluation of irregular bleeding in premenopausal period, and postmenopausal bleeding. Abortion is undoubtedly the number one procedure with more than 44 million pregnancies terminated every year. This procedure should not be underestimated and a careful preoperative evaluation is needed. Ideally a sensitive pregnancy test should be done together with an ultrasound in order to confirm a uterine pregnancy, excluding extra-uterine pregnancy, and to detect genital and/or uterine malformations. Three out of four abortions are performed by surgical methods. Surgical methods include a sharp, blunt, and suction curettage. Suction curettage or vacuum aspiration is the preferred method. Despite the fact that it is a relative safe procedure with major complications in less than one percent of cases, it is still responsible for 13% of all maternal deaths. All the figures have not declined in the last decade. Trauma, perforation, and bleeding are a danger triage. When there is a perforation, a laparoscopy should be performed immediately, in order to detect intra-abdominal lacerations and bleeding. The bleeding should be stopped as soon as possible in order to not destabilize the patient. When there is a perforation in the uterus, this "entrance" can be used to perform the curettage. This is particularly useful if there is trauma of the isthmus and uterine wall, and it is difficult to identify the uterine canal. A curettage is a frequent performed procedure, which should not be underestimated. If there is a perforation in the uterus, then this opening can safely be used for vacuum aspiration.

  18. The technological raw material heating furnaces operation efficiency improving issue (United States)

    Paramonov, A. M.


    The issue of fuel oil applying efficiency improving in the technological raw material heating furnaces by means of its combustion intensification is considered in the paper. The technical and economic optimization problem of the fuel oil heating before combustion is solved. The fuel oil heating optimal temperature defining method and algorithm analytically considering the correlation of thermal, operating parameters and discounted costs for the heating furnace were developed. The obtained optimization functionality provides the heating furnace appropriate thermal indices achievement at minimum discounted costs. The carried out research results prove the expediency of the proposed solutions using.


    NARCIS (Netherlands)


    A novel histoprocessing method for paraffin sections is presented in which the combination of vacuum and microwave exposure is the key element. By exploiting the decrease in boiling temperature under vacuum, the liquid molecules in the tissues have been successfully extracted and exchanged at

  20. Vacuum Technology for Superconducting Devices

    CERN Document Server

    Chiggiato, P


    The basic notions of vacuum technology for superconducting applications are presented, with an emphasis on mass and heat transport in free molecular regimes. The working principles and practical details of turbomolecular pumps and cryopumps are introduced. The specific case of the Large Hadron Collider’s cryogenic vacuum system is briefly reviewed.

  1. Evaporation and Combustion Characteristics of Biomass Vacuum Pyrolysis Oils

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Perez, M. [University of Georgia, Biological and Agricultural Engineering Department, Driftmier Engineering Center, Athens, GA, 30602 (United States); Chaala, A. [Chemical Engineering Department, Universite Laval, Quebec (Canada); Lappas, P.; Hughes, P.; Dell, L. [Energy Research Laboratories, CANMET, Ottawa, ON (Canada); Kretschmer, D. [Mechanical Engineering Department, Universite Laval, Quebec, ON (Canada); Roy, C. [Pyrovac International, Quebec, ON (Canada)


    The evaporation behaviour at high heating rates of vacuum pyrolysis oils obtained from Softwood Bark Residue (SWBR) and from Hardwood Rich in Fibres (HWRF) was studied photographically at the CANMET laminar Entrained Flow Reactor (EFR). For low heating rates, the evaporation and combustion characteristics for each bio-oil were studied by observing the mass loss in pure nitrogen and in air using thermogravimetry. The bio-oil combustion process starts with the evaporation of light compounds followed by the pyrolysis of heavy fractions yielding charcoal. In the final step, the oxygen reacts with charcoal to yield ash. Tests in the EFR were performed using initial droplet diameters between 58 and 62 {mu}m. These diameters fall within the range of sizes observed in SWBR bio-oil sprays. The droplets were generated in a piezo-electric droplet generator and injected into a quartz tube reactor placed inside the furnace. Two furnace wall temperatures (700C and 800C) were used during EFR experiments. For evaporation studies, the EFR was operated in an inert environment (using Ar) while for combustion studies various Ar-O2 mixtures were used (O2 concentration between 20 and 50 vol. %). The photographic results showed that the formation of bubbles inside bio-oil droplets was influenced by heat transfer rates. For the experimental conditions used, no micro-explosions were observed. The solid residues obtained at the furnace exit were collected and analysed by Scanning Electron Microscopy. Two different morphologies of residual particles were observed depending on the frequency of droplet generation: (a) compact and mechanically resistant spheres obtained at low electrical pulse frequencies (less than 500 Hz) with typical diameters of 20-30 {mu}m and (b) fragile 'glass like' cenospheres with thin walls and diameter between 60 and 90 {mu}m obtained at higher droplet generation frequencies (more than 500 Hz)

  2. Detached Melt and Vapor Growth of InI in SUBSA Furnace (United States)

    Ostrogorsky, A. G.; Riabov, V.; Volz, M. P.; van den Berg, L.; Croll, A.


    Indium iodide (InI) is a promising wide energy band gap nuclear detector material. It is ideal for space experiments because it is non-toxic and has a relatively low melting point of only 351 degrees Centigrade. However, it has been established that melt-grown crystals contain a large amount of second phase inclusions/precipitates. The typical size of inclusions are 1 to 27 microns in diameter, while the volume fraction of all sizes is 300 to 600 parts per million. The SEM-EDS (Scanning Electron Microscopy / Energy Dispersive X-Ray Spectroscopy) analysis of the inclusions has revealed that they all contain oxygen and some contain carbon. At present, under sponsorship of NASA and CASIS (Center for the Advancement of Science in Space), we are conducting ground-based experiments with InI in preparation for the flight experiments to be conducted in the SUBSA (Solidification Using a Baffle in Sealed Ampoules) furnace in the Microgravity Science Glovebox at the International Space Station, planned for the summer/fall of 2017. Earth-based experiments include melt and vapor growth conducted in the SUBSA ground unit, measurements of the volumetric expansion coefficient of the melt, and measurements of the wetting angle of molten InI. Finite element modeling has been conducted to optimize the design of the flight ampoules. Alloying with Tl and Ga has given promising results.

  3. Vacuum fiber-fiber coupler (United States)

    Heinrici, Axel; Bjelajac, Goran; Jonkers, Jeroen; Jakobs, Stefan; Olschok, Simon; Reisgen, Uwe


    Research and development carried out by the ISF Welding and Joining Institute of RWTH Aachen University has proven that combining high power laser and low vacuum atmosphere provides a welding performance and quality, which is comparable to electron beam welding. The developed welding machines are still using a beam forming which takes place outside the vacuum and the focusing laser beam has to be introduced to the vacuum via a suitable window. This inflexible design spoils much of the flexibility of modern laser welding. With the target to bring a compact, lightweight flying optics with flexible laser transport fibers into vacuum chambers, a high power fiber-fiber coupler has been adapted by II-VI HIGHYAG that includes a reliable vacuum interface. The vacuum-fiber-fiber coupler (V-FFC) is tested with up to 16 kW sustained laser power and the design is flexible in terms of a wide variety of laser fiber plug systems and vacuum flanges. All that is needed to implement the V-FFC towards an existing or planned vacuum chamber is an aperture of at least 100 mm (4 inch) diameter with any type of vacuum or pressure flange. The V-FFC has a state-of-the-art safety interface which allows for fast fiber breakage detection for both fibers (as supported by fibers) by electric wire breakage and short circuit detection. Moreover, the System also provides connectors for cooling and electric signals for the laser beam optics inside the vacuum. The V-FFC has all necessary adjustment options for coupling the laser radiation to the receiving fiber.

  4. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system. (United States)


    ... 49 Transportation 6 2010-10-01 2010-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake systems...

  5. Microgravity particle research on the Space Station

    Energy Technology Data Exchange (ETDEWEB)

    Squyres, S.W.; Mckay, C.P.; Schwartz, D.E.


    Science questions that could be addressed by a Space Station Microgravity Particle Research Facility for studying small suspended particles were discussed. Characteristics of such a facility were determined. Disciplines covered include astrophysics and the solar nebula, planetary science, atmospheric science, exobiology and life science, and physics and chemistry.

  6. Microgravity Flammability Experiments for Spacecraft Fire Safety

    DEFF Research Database (Denmark)

    Legros, Guillaume; Minster, Olivier; Tóth, Balazs


    As fire behaviour in manned spacecraft still remains poorly understood, an international topical team has been created to design a validation experiment that has an unprecedented large scale for a microgravity flammability experiment. While the validation experiment is being designed for a re-sup...

  7. Validity of microgravity simulation models on earth

    DEFF Research Database (Denmark)

    Regnard, J; Heer, M; Drummer, C


    Many studies have used water immersion and head-down bed rest as experimental models to simulate responses to microgravity. However, some data collected during space missions are at variance or in contrast with observations collected from experimental models. These discrepancies could reflect inc...

  8. CMOS Thermal Ox and Diffusion Furnace: Tystar Tytan 2000 (United States)

    Federal Laboratory Consortium — Description:CORAL Names: CMOS Wet Ox, CMOS Dry Ox, Boron Doping (P-type), Phos. Doping (N-Type)This four-stack furnace bank is used for the thermal growth of silicon...

  9. Innovation in electric arc furnaces scientific basis for selection

    CERN Document Server

    Toulouevski, Yuri N


    This book equips a reader with knowledge necessary for critical analysis of  innovations in electric arc furnaces and helps to select the most effective ones and for their successful implementation. The book also covers general issues related to history of development, current state and prospects of steelmaking in Electric Arc Furnaces. Therefore, it can be useful for everybody who studies metallurgy, including students of colleges and universities. The modern concepts of mechanisms of Arc Furnace processes are are discussed in the book at the level sufficient to solve practical problems: To help readers lacking knowledge required in the field of heat transfer as well as hydro-gas dynamics, it contains several chapters which provide the required minimum of information in these fields of science. In order to better assess different innovations, the book describes experience of the application of similar innovations in open-hearth furnaces and oxygen converters. Some promising ideas on key issues regarding int...

  10. Silica crown refractory corrosion in glass melting furnaces

    National Research Council Canada - National Science Library

    Balandis A; Nizeviciene D


    ... of glass furnaces, when the rate of corrosion of crowns were about 2 times greater. The change of these parameters, the chemical composition and formation of the microcracks in the used silica refractories material were studied...

  11. Alloying and Casting Furnace for Shape Memory Alloys Project (United States)

    National Aeronautics and Space Administration — The concept in the proposed project is to create a melting, alloying and casting furnace for the processing titanium based SMA using cold crucible techniques. The...

  12. Design considerations for solar furnace focal zone apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Sievers, R.H. Jr.; Knasel, T.M.; McDonnell, M.; Gordon, B.; Woods, S.; Malinowski, R.


    Science Applications, Inc. has used the principal solar furnaces in conjunction with its study of the effect of high thermal fluxes and fluences on soil surfaces for the Defense Nuclear Agency. Apparatus to perform these tests has evolved from tests on the furnaces at the White Sands Missile Range, Georgia Institute of Technology in Atlanta; Centre National de Recherche Scientifique in Font Romeu, France; and Kirtland AFB, NM over the past 6 years. The apparatus is still evolving as it is adapted to additional furnaces and to obtain a greater variety of data. The evolution of the apparatus is traced to illustrate the interaction of experiment objectives; furnace capabilities, configuration, and support; apparatus design; data collection; and response to lessons learned.

  13. Hopewell Furnace NHS Small Scale Features (Linear Features) (United States)

    National Park Service, Department of the Interior — This shapefile represents the linear small scale features found at Hopewell Furnace National Historic Site based on the Cultural Landscape Report completed in...


    Directory of Open Access Journals (Sweden)

    Sérgio Boscato Garcia


    Full Text Available Solar cell world market had an exponential growth in the last decade and nowadays it continues in expansion. To produce solar cells, dopants need to be introduced into the crystalline silicon wafer in order to form the pn junction. This process is carried out in diffusion furnaces. The aim of this paper is to present the development of a compact diffusion furnace to process up to 156 mm × 156 mm silicon wafers and to operate at temperature up to 1100°C. The furnace is automated and it is constituted by a heating system with three zones and systems to introduce the wafers inside the furnace as well as to control of gas flows. This equipment is the first one developed in Brazil to promote impurity diffusions in order to produce silicon solar cells and it was manufactured jointly with a Brazilian company.

  15. Optimization of the melting process of electrical furnaces in drenas

    Directory of Open Access Journals (Sweden)

    A. Haxhiaj


    Full Text Available The weight, composition and loads are the main parameters of the melting process in electrical furnace. The charge is roasted in rotary furnace. Roasting of charge which consists of Drenas and Albanians ore is done at about 950°C. Also, article has the experimental analyses that modify some parameters of the production which are the reduction of quantity of limestone and the increase of quantity of quartz in the charge. The paper analysis the possibility of mixing the ore from Kosova with lateritic ore from Albania with the aim of reducing the acidity of weight which is loaded in the electrical furnace. The composition of the furnace must satisfy the ratio 1:10 of ore from Kosova and Albania.

  16. Combustion in microgravity: The French contribution (United States)

    Prud'homme, Roger; Legros, Guillaume; Torero, José L.


    Microgravity (drop towers, parabolic flights, sounding rockets and space stations) are particularly relevant to combustion problems given that they show high-density gradients and in many cases weak forced convection. For some configurations where buoyancy forces result in complex flow fields, microgravity leads to ideal conditions that correspond closely to canonical problems, e.g., combustion of a spherical droplet in a far-field still atmosphere, Emmons' problem for flame spreading over a solid flat plate, deflagration waves, etc. A comprehensive chronological review on the many combustion studies in microgravity was written first by Law and Faeth (1994) and then by F.A. Williams (1995). Later on, new recommendations for research directions have been delivered. In France, research has been managed and supported by CNES and CNRS since the creation of the microgravity research group in 1992. At this time, microgravity research and future activities contemplated the following: Droplets: the "D2 law" has been well verified and high-pressure behavior of droplet combustion has been assessed. The studies must be extended in two main directions: vaporization in mixtures near the critical line and collective effects in dense sprays. Flame spread: experiments observed blue flames governed by diffusion that are in accordance with Emmons' theory. Convection-dominated flames showed significant departures from the theory. Some theoretical assumptions appeared controversial and it was noted that radiation effects must be considered, especially when regarding the role of soot production in quenching. Heterogeneous flames: two studies are in progress, one in Poitiers and the other in Marseilles, about flame/suspension interactions. Premixed and triple flames: the knowledge still needs to be complemented. Triple flames must continue to be studied and understanding of "flame balls" still needs to be addressed.

  17. The Flexibility of Pusher Furnace Grate

    Directory of Open Access Journals (Sweden)

    Słowik J.A.


    Full Text Available The lifetime of guide grates in pusher furnaces for heat treatment could be increased by raising the flexibility of their structure through, for example, the replacement of straight ribs, parallel to the direction of grate movement, with more flexible segments. The deformability of grates with flexible segments arranged in two orientations, i.e. crosswise (perpendicular to the direction of compression and lengthwise (parallel to the direction of compression, was examined. The compression process was simulated using SolidWorks Simulation program. Relevant regression equations were also derived describing the dependence of force inducing the grate deformation by 0.25 mm ‒ modulus of grate elasticity ‒ on the number of flexible segments in established orientations. These calculations were made in Statistica and Scilab programs. It has been demonstrated that, with the same number of segments, the crosswise orientation of flexible segments increases the grate structure flexibility in a more efficient way than the lengthwise orientation. It has also been proved that a crucial effect on the grate flexibility has only the quantity and orientation of segments (crosswise / lengthwise, while the exact position of segments changes the grate flexibility by less than 1%.

  18. Investigation of radiative heat transfer in fixed bed biomass furnaces

    Energy Technology Data Exchange (ETDEWEB)

    T. Klason; X.S. Bai; M. Bahador; T.K. Nilsson; B. Sunden [Lund Institute of Technology, Lund (Sweden). Division of Fluid Mechanics


    This paper presents an investigation of the radiative heat transfer process in two fixed bed furnaces firing biomass fuels and the performance of several widely used models for calculation of radiative heat transfer in the free-room of fixed bed furnaces. The effective mean grey gas absorption coefficients are calculated using an optimised version of the exponential wide band model (EWBM) based on an optical mean beam length. Fly-ash and char particles are taken into account using Mie scattering. In the investigated updraft small-scale fixed bed furnace radiative transfer carries heat from the bed to the free-room, whereas in the cross-current bed large-scale industry furnace, radiative transfer brings heat from the hot zones in the free-room to the drying zone of the bed. Not all the investigated models can predict these heat transfer trends, and the sensitivity of results to model parameters is fairly different in the two furnaces. In the small-scale furnace, the gas absorption coefficient predicted by using different optical lengths has great impact on the predicted temperature field. In the large-scale furnaces, the predicted temperature field is less sensitive to the optical length. In both furnaces, with the same radiative properties, the low-computational-cost P1 model predicts a temperature field in the free-room similar to that by the more time consuming SLW model. In general, the radiative heat transfer rates to the fuel bed are not very sensitive to the radiative properties, but they are sensitive to the different radiative heat transfer models. For a realistic prediction of the radiative heat transfer rate to the fuel bed or to the walls, more computationally demanding models such as the FGG or SLW models should be used. 37 refs., 7 figs., 2 tabs.

  19. Mathematical model and software for control of commissioning blast furnace (United States)

    Spirin, N. A.; Onorin, O. P.; Shchipanov, K. A.; Lavrov, V. V.


    Blowing-in is a starting period of blast furnace operation after construction or major repair. The current approximation methods of blowing-in burden analysis are based on blowing-in practice of previously commissioned blast furnaces. This area is theoretically underexplored; there are no common scientifically based methods for selection of the burden composition and blast parameters. The purpose of this paper is development and scientific substantiation of the methods for selection of the burden composition and blast parameters in the blast furnace during the blowing-in period. Research methods are based on physical regularities of main processes running in the blast furnace, system analysis, and application of modern principles for development and construction of mathematical models, algorithms and software designed for automated control of complex production processes in metallurgy. As consequence of the research made by the authors the following results have been achieved: 1. A set of mathematical models for analysis of burden arrangement throughout the height of the blast furnace and for selection of optimal blast and gas dynamic parameters has been developed. 2. General principles for selection of the blowing-in burden composition and blast and gas dynamic parameters have been set up. 3. The software for the engineering and process staff of the blast furnace has been developed and introduced in the industry.

  20. Similarity of Ferrosilicon Submerged Arc Furnaces With Different Geometrical Parameters

    Directory of Open Access Journals (Sweden)

    Machulec B.


    Full Text Available In order to determine reasons of unsatisfactory production output regarding one of the 12 MVA furnaces, a comparative analysis with a furnace of higher power that showed a markedly better production output was performed. For comparison of ferrosilicon furnaces with different geometrical parameters and transformer powers, the theory of physical similarity was applied. Geometrical, electrical and thermal parameters of the reaction zones are included in the comparative analysis. For furnaces with different geometrical parameters, it is important to ensure the same temperature conditions of the reaction zones. Due to diverse mechanisms of heat generation, different criteria for determination of thermal and electrical similarity for the upper and lower reaction zones were assumed contrary to other publications. The parameter c3 (Westly was assumed the similarity criterion for the upper furnace zones where heat is generated as a result of resistive heating while the parameter J1 (Jaccard was assumed the similarity criterion for the lower furnace zones where heat is generated due to arc radiation.


    Directory of Open Access Journals (Sweden)

    E. D. Chertov


    Full Text Available The work is devoted to the creation of a new type of mixer to produce homogeneous mixtures of dissimilar materials applied to recycling of housing and communal services waste. The article describes the design of a dual-chamber device of the original high-temperature vacuum mixer, there investigated the processes occurring in the chambers of such devices. The results of theoretical and experimental research of the process of mixing recycled polyethylene with a mixture of "grinded food waste – Eco wool” are presented. The problem of the optimum choice of bending the curvilinear blades in the working volume of the seal, which is achieved by setting their profile in the form of involute arc of several circles of different radii, is examined . The dependences, allowing to define the limits of the changes of the main mode parameters the angular velocity of rotation of the working body of the mixer using two ways of setting the profile of the curvilinear blade mixer are obtained. Represented design of the mixer is proposed to use for a wide range of tasks associated with the mixing of the components with a strongly pronounced difference of physic al chemical properties and, in particular, in the production of composites out of housing and communal services waste.

  2. Experimental tests of vacuum energy

    CERN Multimedia

    CERN. Geneva


    While the current vacuum energy of the Universe is very small, in our standard cosmological picture it has been much larger at earlier epochs. We try to address the question of what are possible ways to try to experimentally verify this. One direction is to look for systems where vacuum energy constitutes a non-negligible fraction of the total energy, and study the properties of those. Another possibility is to focus on the epochs around cosmic phase transitions, when the vacuum energy is of the same order as the total energy. Along these lines we investigate properties of neutron stars and the imprint of phase transitions on primordial gravitational waves.

  3. Assessing energy efficiency of electric car bottom furnaces intended for thermal energization of minerals (United States)

    Nizhegorodov, A. I.


    The paper deals with a new concept of electric furnaces for roasting and thermal energization of vermiculite and other minerals with vibrational transportation of a single-layer mass under constant thermal field. The paper presents performance calculation and comparative assessment of energy data for furnaces of different modifications: flame and electric furnaces with three units, furnaces with six units and ones with series-parallel connection of units, and furnaces of new concept.

  4. Experimental elaboration of liquid droplet cooler-radiator models under microgravity and deep vacuum conditions (United States)

    Koroteev, A. A.; Nagel, Yu. A.; Filatov, N. I.


    The basic results of space tests of liquid droplet cooler-radiator models as the main elements of frameless systems for low-grade heat rejection are considered. The studies carried out have been analyzed and intermediate elaboration's results are summarized, which concern (1) the development of generators of droplet propellant flows, (2) revealing an operational behavior of fluid collectors of various types and analysis of unsolved problems associated with droplet collection upon the open trajectory's section passage, and (3) provision of the coolant circulation contour's closing. The necessity is substantiated for the activization of works directed to carrying out space experiments with improved radiator models and new promising propellants in order to provide a possibility of creating new space power plants characterized by megawatt power levels.

  5. Carbothermic reduction of electric arc furnace dust and calcination of waelz oxide by semi-pilot scale rotary furnace

    National Research Council Canada - National Science Library

    Morcali M.H; Yucel O; Aydin A; Derin B


    The paper gives a common outline about the known recycling techniques from electric arc furnace dusts and describes an investigation of a pyrometallurgical process for the recovery of zinc and iron...


    Directory of Open Access Journals (Sweden)

    S. V. Terletski


    Full Text Available The technological peculiarities of melting and out-of-furnace processing of balanced steels in conditions of electric furnace steelmaking and continuous cast of RUP “BMZ” are considered.

  7. Plant Cell Adaptive Responses to Microgravity (United States)

    Kordyum, Elizabeth; Kozeko, Liudmyla; Talalaev, Alexandr

    Microgravity is an abnormal environmental condition that plays no role in the functioning of biosphere. Nevertheless, the chronic effect of microgravity in space flight as an unfamiliar factor does not prevent the development of adaptive reactions at the cellular level. In real microgravity in space flight under the more or less optimal conditions for plant growing, namely temperature, humidity, CO2, light intensity and directivity in the hardware angiosperm plants perform an “reproductive imperative”, i.e. they flower, fruit and yield viable seeds. It is known that cells of a multicellular organism not only take part on reactions of the organism but also carry out processes that maintain their integrity. In light of these principles, the problem of the identification of biochemical, physiological and structural patterns that can have adaptive significance at the cellular and subcellular level in real and simulated microgravity is considered. Cytological studies of plants developing in real and simulated microgravity made it possible to establish that the processes of mitosis, cytokinesis, and tissue differentiation of vegetative and generative organs are largely normal. At the same time, under microgravity, essential reconstruction in the structural and functional organization of cell organelles and cytoskeleton, as well as changes in cell metabolism and homeostasis have been described. In addition, new interesting data concerning the influence of altered gravity on lipid peroxidation intensity, the level of reactive oxygen species, and antioxidant system activity, just like on the level of gene expression and synthesis of low-molecular and high-molecular heat shock proteins were recently obtained. So, altered gravity caused time-dependent increasing of the HSP70 and HSP90 levels in cells, that may indicate temporary strengthening of their functional loads that is necessary for re-establish a new cellular homeostasis. Relative qPCR results showed that

  8. Cellular consequences of the microgravity environment on lymphocyte function (United States)

    Sundaresan, A.; Pellis, N. R.

    Microgravity induces a cascade of changes in cell morphology and function. Mammalian cells adapt to the environment of low gravity and express a series of responses, some possibly from direct effects on cells and others based on environmental conditions created by microgravity. Human lymphocytes in microgravity culture are functionally diminished in activation and locomotion. Both processes are integral to optimal immune response to fight pathogens. The NASA Rotating-wall vessel (RWV) is an analog to many aspects of microgravity and is used to model microgravity for ground-based experiments. We found that lymphocyte activation and locomotion were significantly down-regulated in spaceflight and in the RWV. Using this analog culture system, we have isolated a signal transduction lesion either at the level of, or upstream from, Protein kinase C (PKC) activation. Analysis of expression and adaptation by gene array experiments and immunoblotting to identified upstream events in human lymphocytes adapting to microgravity analog culture. Microgravity induces selective changes, many of which are cell membrane related. Results showed that upstream of PKC in the T cell activation cascade, PLC-gamma and LAT are significantly diminished. ZAP 70 which controls LAT activation is also down-regulated in modeled microgravity indicating that events governing cell shape might warrant special attention in microgravity conditions. The goal of this study is to delineate response suites which are consequential, direct or indirect effects of the microgravity environment and which of these are essential to lymphocytes.

  9. Alumina barrier for vacuum brazing (United States)

    Beuyukian, C. S.


    Heating platens of vacuum-brazing press will not stick to workpiece if aluminum oxide "paper" is interposed. Paper does not disintegrate in press, will not contaminate braze alloy, and helps form smoothly contoured, regular fillet at brazed edges.

  10. [Endoscopic vacuum-assisted closure]. (United States)

    Wedemeyer, J; Lankisch, T


    Anastomotic leakage in the upper and lower intestinal tract is associated with high morbidity and mortality. Within the last 10 years endoscopic treatment options have been accepted as sufficient treatment option of these surgical complications. Endoscopic vacuum assisted closure (E-VAC) is a new innovative endoscopic therapeutic option in this field. E-VAC transfers the positive effects of vacuum assisted closure (VAC) on infected cutaneous wounds to infected cavities that can only be reached endoscopically. A sponge connected to a drainage tube is endoscopically placed in the leakage and a continuous vacuum is applied. Sponge and vacuum allow removal of infected fluids and promote granulation of the leakage. This results in clean wound grounds and finally allows wound closure. Meanwhile the method was also successfully used in the treatment of necrotic pancreatitis.

  11. Vacuum production; Produccion de vacio

    Energy Technology Data Exchange (ETDEWEB)

    Segovia, J. L. de


    Since the advent of ultra high vacuum in 1958 has been a great demand for new as means of production and to meet the process needs to be done: industry heavy, high technology and space research areas, large accelerator systems particles or nuclear fusion. In this paper we explore the modern media production: dry vacuum pumps, turbo pumps, pump status diffusion ion pumps and cryopumps. (Author)

  12. Edge conduction in vacuum glazing

    Energy Technology Data Exchange (ETDEWEB)

    Simko, T.M.; Collins, R.E. [Sydney Univ., NSW (Australia). Dept. of Applied Physics; Beck, F.A.; Arasteh, D. [Lawrence Berkeley Lab., CA (United States)


    Vacuum glazing is a form of low-conductance double glazing using in internal vacuum between the two glass sheets to eliminate heat transport by gas conduction and convection. An array of small support pillars separates the sheets; fused solder glass forms the edge seal. Heat transfer through the glazing occurs by radiation across the vacuum gap, conduction through the support pillars, and conduction through the bonded edge seal. Edge conduction is problematic because it affects stresses in the edge region, leading to possible failure of the glazing; in addition, excessive heat transfer because of thermal bridging in the edge region can lower overall window thermal performance and decrease resistance to condensation. Infrared thermography was used to analyze the thermal performance of prototype vacuum glazings, and, for comparison, atmospheric pressure superwindows. Research focused on mitigating the edge effects of vacuum glazings through the use of insulating trim, recessed edges, and framing materials. Experimentally validated finite-element and finite-difference modeling tools were used for thermal analysis of prototype vacuum glazing units and complete windows. Experimental measurements of edge conduction using infrared imaging were found to be in good agreement with finite-element modeling results for a given set of conditions. Finite-element modeling validates an analytic model developed for edge conduction.

  13. Vacuum-assisted cesarean section

    Directory of Open Access Journals (Sweden)

    McQuivey RW


    Full Text Available Ross W McQuivey,1 Jon E Block2 1Clinical Innovations, Salt Lake City, UT, 2Independent consultant, San Francisco, CA, USA Abstract: There has been a dramatic rise in the frequency of cesarean sections, surpassing 30% of all deliveries in the US. This upsurge, coupled with a decreasing willingness to allow vaginal birth after cesarean section, has resulted in an expansion of the use of vacuum assistance to safely extract the fetal head. By avoiding the use of a delivering hand or forceps blade, the volume being delivered through the uterine incision can be decreased when the vacuum is used properly. Reducing uterine extensions with their associated complications (eg, excessive blood loss in difficult cases is also a theoretical advantage of vacuum delivery. Maternal discomfort related to excessive fundal pressure may also be lessened. To minimize the risk of neonatal morbidity, proper cup placement over the “flexion point” remains essential to maintain vacuum integrity and reduce the chance of inadvertent detachment and uterine extensions. Based on the published literature and pragmatic clinical experience, utilization of the vacuum device is a safe and effective technique to assist delivery during cesarean section. Keywords: cesarean section, vacuum, forceps, birth, delivery

  14. Technical specification for vacuum systems

    Energy Technology Data Exchange (ETDEWEB)

    Khaw, J. (ed.)


    The vacuum systems at the Stanford Linear Accelerator Center (SLAC) are primarily of all-metal construction and operate at pressures from 10/sup -5/ to 10/sup -11/ Torr. The primary gas loads during operation result from thermal desorption and beam-induced desorption from the vacuum chamber walls. These desorption rates can be extremely high in the case of hydrocarbons and other contaminants. These specifications place a major emphasis on eliminating contamination sources. The specifications and procedures have been written to insure the cleanliness and vacuum integrity of all SLAC vacuum systems, and to assist personnel involved with SLAC vacuum systems in choosing and designing components that are compatible with existing systems and meet the quality and reliability of SLAC vacuum standards. The specification includes requirements on design, procurement, fabrication, chemical cleaning, clean room practices, welding and brazing, helium leak testing, residual gas analyzer testing, bakeout, venting, and pumpdown. Also appended are specifications regarding acceptable vendors, isopropyl alcohol, bakeable valve cleaning procedure, mechanical engineering safety inspection, notes on synchrotron radiation, and specifications of numerous individual components. (LEW)

  15. Transitional Gas Jet Diffusion Flames in Microgravity (United States)

    Agrawal, Ajay K.; Alammar, Khalid; Gollahalli, S. R.; Griffin, DeVon (Technical Monitor)


    Drop tower experiments were performed to identify buoyancy effects in transitional hydrogen gas jet diffusion flames. Quantitative rainbow schlieren deflectometry was utilized to optically visualize the flame and to measure oxygen concentration in the laminar portion of the flame. Test conditions consisted of atmospheric pressure flames burning in quiescent air. Fuel from a 0.3mm inside diameter tube injector was issued at jet exit Reynolds numbers (Re) of 1300 to 1700. Helium mole percentage in the fuel was varied from 0 to 40%. Significant effects of buoyancy were observed in near field of the flame even-though the fuel jets were momentum-dominated. Results show an increase of breakpoint length in microgravity. Data suggest that transitional flames in earth-gravity at Re<1300 might become laminar in microgravity.

  16. Glucocorticoid: A potential role in microgravity-induced bone loss (United States)

    Yang, Jiancheng; Yang, Zhouqi; Li, Wenbin; Xue, Yanru; Xu, Huiyun; Li, Jingbao; Shang, Peng


    Exposure of animals and humans to conditions of microgravity, including actual spaceflight and simulated microgravity, results in numerous negative alterations to bone structure and mechanical properties. Although there are abundant researches on bone loss in microgravity, the explicit mechanism is not completely understood. At present, it is widely accepted that the absence of mechanical stimulus plays a predominant role in bone homeostasis disorders in conditions of weightlessness. However, aside from mechanical unloading, nonmechanical factors such as various hormones, cytokines, dietary nutrition, etc. are important as well in microgravity induced bone loss. The stress-induced increase in endogenous glucocorticoid (GC) levels is inevitable in microgravity environments. Moreover, it is well known that GCs have a detrimental effect to bone health at excess concentrations. Therefore, GC plays a potential role in microgravity-induced bone loss. This review summarizeds several studies and their prospective solutions to this hypothesis.

  17. Microgravity smoldering combustion on the USML-1 Space Shuttle mission (United States)

    Stocker, Dennis P.; Olson, Sandra L.; Torero, Jose L.; Fernandez-Pello, A. Carlos


    Preliminary results from an experimental study of the smolder characteristics of a porous combustible material (flexible polyurethane foam) in normal and microgravity are presented. The experiments, limited in fuel sample size and power available for ignition, show that the smolder process was primarily controlled by heat losses from the reaction to the surrounding environment In microgravity, the reduced heat losses due to the absence of natural convection result in only slightly higher temperatures in the quiescent microgravity test than in normal gravity, but a dramatically larger production of combustion products in all microgravity tests. Particularly significant is the proportionately larger amount of carbon monoxide and light organic compounds produced in microgravity, despite comparable temperatures and similar char patterns. This excessive production of fuel-rich combustion products may be a generic characteristic of smoldering polyurethane in microgravity, with an associated increase in the toxic hazard of smolder in spacecraft.

  18. Effect of microgravity on plant growth (United States)

    Lewis, Norman G.


    The overall goal of this research is to determine the effect of microgravity proper on plant growth (metabolism and cell wall formation). In addressing this goal, the work conducted during this grant period was divided into three components: analyses of various plant tissues previously grown in space aboard MIR Space Station; analyses of wheat tissues grown on Shuttle flight STS-51; and Phenylpropanoid metabolism and plant cell wall synthesis (earth-based investigations).

  19. Pregnancy and Beyond Part IV: Microgravity


    Borkenhagen, Rainer H.


    Transport technology in the last 35 years has created new environmental frontiers in which family physicians are, and will continue to be, involved both in research and in administering patient care. Some frontiers address basic physiological problems that cross over into others. In a series of four articles, the author describes six of these frontiers with specific emphasis on pregnancy, from hyperbarism (undersea physiology) to microgravity (space physiology), the problems, and linkages whe...

  20. Microgravity, Mesh-Crawling Legged Robots (United States)

    Behar, Alberto; Marzwell, Neville; Matthews, Jaret; Richardson, Krandalyn; Wall, Jonathan; Poole, Michael; Foor, David; Rodgers, Damian


    The design, fabrication, and microgravity flight-testing are part of a continuing development of palm-sized mobile robots that resemble spiders (except that they have six legs apiece, whereas a spider has eight legs). Denoted SpiderBots (see figure), they are prototypes of proposed product line of relatively inexpensive walking robots that could be deployed in large numbers to function cooperatively in construction, repair, exploration, search, and rescue activities in connection with exploration of outer space and remote planets.

  1. Bacillus thuringiensis Conjugation in Simulated Microgravity (United States)

    Beuls, Elise; van Houdt, Rob; Leys, Natalie; Dijkstra, Camelia; Larkin, Oliver; Mahillon, Jacques


    Spaceflight experiments have suggested a possible effect of microgravity on the plasmid transfer among strains of the Gram-positive Bacillus thuringiensis, as opposed to no effect recorded for Gram-negative conjugation. To investigate these potential effects in a more affordable experimental setup, three ground-based microgravity simulators were tested: the Rotating Wall Vessel (RWV), the Random Positioning Machine (RPM), and a superconducting magnet. The bacterial conjugative system consisted in biparental matings between two B. thuringiensis strains, where the transfer frequencies of the conjugative plasmid pAW63 and its ability to mobilize the nonconjugative plasmid pUB110 were assessed. Specifically, potential plasmid transfers in a 0-g position (simulated microgravity) were compared to those obtained under 1-g (normal gravity) condition in each device. Statistical analyses revealed no significant difference in the conjugative and mobilizable transfer frequencies between the three different simulated microgravitational conditions and our standard laboratory condition. These important ground-based observations emphasize the fact that, though no stimulation of plasmid transfer was observed, no inhibition was observed either. In the case of Gram-positive bacteria, this ability to exchange plasmids in weightlessness, as occurs under Earth's conditions, should be seen as particularly relevant in the scope of spread of antibiotic resistances and bacterial virulence.

  2. Smoldering, Transition and Flaming in Microgravity (United States)

    Fernandez-Pello, A. C.; Bar-Ilan, A.; Lo, T. L.; Walther, D. C.; Urban, D. L.


    A research project is underway to study smolder and the transition to flaming in microgravity. The Microgravity Smoldering Combustion (MSC) flight project is an ongoing research project to provide a better understanding of the controlling mechanisms of smoldering combustion. The Smoldering Transition and Flaming (STAF) project is a recently established research program that will utilize the Fluids and Combustion Facility (FCF) of the ISS to examine the transition from smolder to flaming in microgravity. In forced flow smolder experiments ambient pressure in the MSC chamber rises, thus motivating the need to understand the effects of pressure on smoldering combustion. Further, the STAF experiment has constraints on experimental scale and testing at elevated pressure may be a mechanism to reduce the sample size by enhancing the smolder reaction. In the work we are reporting here, a series of ground-based tests determine the effects of pressure on smoldering combustion. These tests are compared with data obtained from experiments conducted aboard the Space Shuttle in flights STS-69 and STS-77. Measurements of one-dimensional smolder propagation velocity are made by thermocouple probing and a non-intrusive Ultrasound Imaging System (UIS)]. Thermocouples are also used to obtain reaction temperatures and the UIS is used to determine permeabilities of the fuel in real-time.

  3. Single Electron Transistor Platform for Microgravity Proteomics Project (United States)

    National Aeronautics and Space Administration — Proteomic studies in microgravity are crucial to understanding the health effects of spaceflight on astronauts. Unfortunately, existing tools for measuring protein,...

  4. Quantitative Measurement of Oxygen in Microgravity Combustion (United States)

    Silver, Joel A.


    A low-gravity environment, in space or in ground-based facilities such as drop towers, provides a unique setting for studying combustion mechanisms. Understanding the physical phenomena controlling the ignition and spread of flames in microgravity has importance for space safety as well as for better characterization of dynamical and chemical combustion processes which are normally masked by buoyancy and other gravity-related effects. Due to restrictions associated with performing measurements in reduced gravity, diagnostic methods which have been applied to microgravity combustion studies have generally been limited to capture of flame emissions on film or video, laser Schlieren imaging and (intrusive) temperature measurements using thermocouples. Given the development of detailed theoretical models, more sophisticated diagnostic methods are needed to provide the kind of quantitative data necessary to characterize the properties of microgravity combustion processes as well as provide accurate feedback to improve the predictive capabilities of the models. When the demands of space flight are considered, the need for improved diagnostic systems which are rugged, compact, reliable, and operate at low power becomes apparent. The objective of this research is twofold. First, we want to develop a better understanding of the relative roles of diffusion and reaction of oxygen in microgravity combustion. As the primary oxidizer species, oxygen plays a major role in controlling the observed properties of flames, including flame front speed (in solid or liquid flames), extinguishment characteristics, flame size and flame temperature. The second objective is to develop better diagnostics based on diode laser absorption which can be of real value in both microgravity combustion research and as a sensor on-board Spacelab as either an air quality monitor or as part of a fire detection system. In our prior microgravity work, an eight line-of-sight fiber optic system measured

  5. RFQ Vacuum brazing at CERN

    CERN Document Server

    Mathot, S


    The aim of this paper is to describe the vacuum brazing procedure used at CERN for the brazing of Radio Frequency Quadrupole (RFQ). The RFQ is made of high precision machined OFE copper pieces assembled together. Vacuum brazing is one of the most promising techniques used to join the individual components leading to vacuum tightness and high precision alignment. The RFQ modules brazed at CERN are made of four 100 or 120 cm long vanes (two major and two minor vanes). Our brazing procedure consists of two steps. The first step involves the brazing of the four vanes in a horizontal position. The second step consists of brazing the vacuum stainless steel flanges to the copper structure in a vertical position. The paper describes the problems encountered with the alignment and the vacuum tightness. The difficulties related to the stress relaxation of the machined copper pieces during the brazing heat treatment are discussed. In addition, the solutions developed to improve the alignment of the brazed RFQ’s are...

  6. Measurement of partial pressures in vacuum technology and vacuum physics (United States)

    Huber, W. K.


    It is pointed out that the measurement of gaseous pressures of less than 0.0001 torr is based on the ionization of gas atoms and molecules due to collisions with electrons. The particle density is determined in place of the pressure. The ionization cross sections for molecules of various gases are discussed. It is found that the true pressure in a vacuum system cannot be determined with certainty if it is unknown which gas is present. Effects of partial pressure determination on the condition of the vacuum system are discussed together with ion sources, systems of separation, and ion detection.

  7. Compacting of fly dusts from cupola and electric arc furnace

    Directory of Open Access Journals (Sweden)

    D. Baricová


    Full Text Available Recycling and utilization of dust waste is important not only from the point of view of its usage as an alternative source of raw materials, but regarding the environmental problems also. Dust emissions arise from thermal and chemical or physical processes and mechanical actions. Two kinds of fl y dusts from cupola furnaces (hot and cold blast cupola furnace and fl y dust from electric arc furnace were used by experiments. They were pelletized only with addition of water and briquetted with diff erent addition of water glass, bentonite and cement. Quality of briquettes was tested by compression – strength test and by break down test in green state, after drying and afterstoring (1 month.

  8. Gas dynamics of reactive gases in swirling-type furnace (United States)

    Akhmetshina, A. I.; Pavlov, G. I.; Sabirzyanov, A. N.; Tikhonov, O. A.


    It is known from the literature that for the complete reaction of two gases (fuel and oxidizer), it is necessary to fulfill three basic conditions: the stoichiometric ratio of reactive gases, qualitative mixing and ensuring the cooling of combustion products without "quenching". Of the above-stated conditions it is more difficult to organize a qualitative mixture formation. This physical process requires additional expenditure of energy flow. In this work we present the results of experimental and theoretical studies of the gas dynamics of a reactive gas mixture in a swirling-type furnace. The design scheme of the furnace includes two reaction zones for combustible components: the first zone is the zone of generation of combustible gases which composition is constant; the second zone of the furnace - zone of a homogeneous combustion reaction.

  9. A feasibility assessment of cogeneration from a regenerative glass furnace

    Energy Technology Data Exchange (ETDEWEB)

    Hnat, J.G.; Coles, W.F.


    In typical oil/gas-fired regenerative glass furnaces, approximately one-third of the total thermal input is exhausted out the stack at temperatures in the range of 700-1000/sup 0/F. The results of a site specific feasibility assessment of cogeneration from the stack gas waste heat of a regenerative glass furnace is summarized. Three different cogeneration concepts were evaluated for heat recovery. They included: a) a conventional steam Rankine cycle, b) an organic Rankine cycle, and c) a pressurized Brayton cycle. The performance and economics of the three cogeneration heat recovery systems are compared for a range of flue gas temperatures and flow rates which encompass expected operating conditions for a nominal furnace campaign period.

  10. Lung volumes during sustained microgravity on Spacelab SLS-1 (United States)

    Elliott, Ann R.; Prisk, G. Kim; Guy, Harold J. B.; West, John B.


    Gravity is known to influence the mechanical behavior of the lung and chest wall. However, the effect of sustained microgravity (microgravity) on lung volumes has not been reported. Pulmonary function tests were performed by four subjects before, during, and after 9 days of microgravity exposure. Ground measurements were made in standing and supine postures. Tests were performed using a bag-in-box-and-flowmeter system and a respiratory mass spectrometer. Measurements included functional residual capacity (FRC), expiratory reserve volume (ERV), residual volume (RV), inspiratory and expiratory vital capacities (IVC and EVC), and tidal volume (V9sub T)). Total lung capacity (TLC) was derived from the measured EVC and RV values. With preflight standing values as a comparison, FRC was significantly reduced by 15% (approximately 500 ml) in microgravity and 32% in the supine posture. ERV was reduced by 10 - 20% in microgravity and decreased by 64% in the supine posture. RV was significantly reduced by 18% (310 ml) in microgravity but did not significantly change in the supine posture compared with standing. IVC and EVC were slightly reduced during the first 24 h of microgravity but returned to 1-G standing values within 72 h of microgravity exposure. IVC and EVC in the supine posture were significantly reduced by 12% compared with standing. During microgravity, V(sub T) decreased by 15% (approximately 90 ml), but supine V(sub T) was unchanged compared with preflight standing values. TLC decreased by approximately 8% during microgravity and in the supine posture compared with preflight standing. The reductions in FRC, ERV, and RV during microgravity are probably due to the cranial shift of the diaphragm, an increase in intrathoracic blood volume, and more uniform alveolar expansion.

  11. Microscale Digital Vacuum Electronic Gates (United States)

    Manohara, Harish (Inventor); Mojarradi, Mohammed M. (Inventor)


    Systems and methods in accordance with embodiments of the invention implement microscale digital vacuum electronic gates. In one embodiment, a microscale digital vacuum electronic gate includes: a microscale field emitter that can emit electrons and that is a microscale cathode; and a microscale anode; where the microscale field emitter and the microscale anode are disposed within at least a partial vacuum; where the microscale field emitter and the microscale anode are separated by a gap; and where the potential difference between the microscale field emitter and the microscale anode is controllable such that the flow of electrons between the microscale field emitter and the microscale anode is thereby controllable; where when the microscale anode receives a flow of electrons, a first logic state is defined; and where when the microscale anode does not receive a flow of electrons, a second logic state is defined.

  12. Carbon nanotubes based vacuum gauge (United States)

    Rudyk, N. N.; Il’in, O. I.; Il’ina, M. V.; Fedotov, A. A.; Klimin, V. S.; Ageev, O. A.


    We have created an ionization type Vacuum gauge with sensor element based on an array of vertically aligned carbon nanotubes. Obtained asymmetrical current-voltage characteristics at different voltage polarity on the electrode with the CNTs. It was found that when applying a negative potential on an electrode with the CNTs, the current in the gap is higher than at a positive potential. In the pressure range of 1 ÷ 103 Torr vacuum gauge sensitivity was 6 mV/Torr (at a current of 4.5·10-5 A) and in the range of 10-5 ÷ 1 Torr was 10 mV/Torr (at a current of 1.3·10-5 A). It is shown that the energy efficiency of vacuum gauge can be increased in the case where electrode with CNT operates as an emitter of electrons.


    Energy Technology Data Exchange (ETDEWEB)



    Some recent work (Walker 2001, Andrews 2002) has indicated that installing a modulating furnace in a conventional duct system may, in many cases, result in a significant degradation in thermal distribution efficiency. The fundamental mechanism was pointed out nearly two decades ago (Andrews and Krajewski 1985). The problem occurs in duct systems that are less-than-perfectly insulated (e.g., R-4 duct wrap) and are located outside the conditioned space. It stems from the fact that when the airflow rate is reduced, as it will be when the modulating furnace reduces its heat output rate, the supply air will have a longer residence time in the ducts and will therefore lose a greater percentage of its heat by conduction than it did at the higher airflow rate. The impact of duct leakage, on the other hand, is not expected to change very much under furnace modulation. The pressures in the duct system will be reduced when the airflow rate is reduced, thus reducing the leakage per unit time. This is balanced by the fact that the operating time will increase in order to meet the same heating load as with the conventional furnace operating at higher output and airflow rates. The balance would be exact if the exponent in the pressure vs. airflow equation were the same as that in the pressure vs. duct leakage equation. Since the pressure-airflow exponent is usually {approx}0.5 and the pressure-leakage exponent is usually {approx}0.6, the leakage loss as a fraction of the load should be slightly lower for the modulating furnace. The difference, however, is expected to be small, determined as it is by a function with an exponent equal to the difference between the above two exponents, or {approx}0.1. The negative impact of increased thermal conduction losses from the duct system may be partially offset by improved efficiency of the modulating furnace itself. Also, the modulating furnace will cycle on and off less often than a single-capacity model, and this may add a small amount

  14. Optimizing of Work Arc Furnace to Decopperisation of Flash Slag

    Directory of Open Access Journals (Sweden)

    Bydałek A.W.


    Full Text Available Discusses an attempt to optimize the operation of an electric furnace slag to be decopperisation suspension of the internal recycling process for the production of copper. The paper presents a new method to recover copper from metallurgical slags in arc-resistance electric furnace. It involves the use of alternating current for a first period reduction, constant or pulsed DC in the final stage of processing. Even distribution of the electric field density in the final phase of melting caused to achieve an extremely low content of metallic copper in the slag phase. They achieved by including the economic effects by reducing the time reduction.

  15. Secondary Aluminum Melting Research in a Laboratory Scale Reverberatory Furnace

    Energy Technology Data Exchange (ETDEWEB)

    Clark, J.A., III


    The Albany Research Center (ARC), U.S. Department of Energy, has developed a 175-pound capacity, natural gas, direct-fired reverberatory furnace. The high temperature reactions present during the aluminum remelt process are being investigated. Preventing dross formation has been the key aim to date. Reducing losses to dross by 25-50% will potentially lead to an annual energy savings of over 75 trillion BTU's by the year 2020. Schematics and operation characteristics of the ARC Laboratory Scale Reverberatory Furnace (LSRF) will be presented. Potential gas-solid, gas-liquid, and liquid-solid interactions between the hot combustion gases, aluminum, and refractories will be discussed.

  16. Modeling the Gas-Solid Flow in Calcining Furnace

    Directory of Open Access Journals (Sweden)

    Haiyan Luo


    Full Text Available Gas-solid two-phase flow in calcining furnace is investigated in this paper. The turbulent fluid phase is calculated using the RNG k-e two-equation model in the Eulerain framework while the solid phase being handled via the particle stochastic trajectory model is calculated in the Lagrangian framework. Flow pattern characteristics of the fluid phase and the particle trajectories of the solid phase were predicted subject to a range of flow conditions and different particle sizes. The computed results provided useful information in the preview of kinetics regulation of the gas-solid two-phase in calcining furnace.

  17. Vacuum Cleaner Fan Being Improved (United States)

    Tweedt, Daniel L.


    As part of the technology utilization program at the NASA Lewis Research Center, efforts are underway to transfer aerospace technologies to new areas of practical application. One such effort involves using advanced computational fluid dynamics (CFD) codes for turbomachinery to analyze the internal fluid dynamics of low-speed fans and blowers. This year, the Kirby Company in Cleveland, Ohio, approached NASA with a request for technologies that could help them improve their vacuum cleaners. Of particular interest to Kirby is the high-frequency blade-passing noise generation of their vacuum cleaner fan at low airflow rates.

  18. NASA's Bioreactor: Growing Cells in a Microgravity Environment. Educational Brief. (United States)

    National Aeronautics and Space Administration, Washington, DC.

    This brief discusses growing cells in a microgravity environment for grades 9-12. Students are provided with plans for building a classroom bioreactor that can then be used with the included activity on seed growth in a microgravity environment. Additional experimental ideas are also suggested along with a history and background on microgravity…

  19. Gases and vacua handbook of vacuum physics

    CERN Document Server

    Beck, A H


    Handbook of Vacuum Physics, Volume 1: Gases and Vacua provides information on the many aspects of vacuum technology, from material on the quantum theoretical aspects of the complex semi-conductors used for thermionic and photo-electric emission to data on the performance of commercially available pumps, gauges, and high-vacuum materials. The handbook satisfies the need of workers using vacuum apparatuses or works on the diverse applications of high-vacuum technology in research and industry. The book is a compilation of long articles prepared by experts in vacuum technology. Sufficient theoret

  20. Effects of microgravity on osteoblast growth (United States)

    Hughes-Fulford, M.; Tjandrawinata, R.; Fitzgerald, J.; Gasuad, K.; Gilbertson, V.


    Studies from space flights over the past two decades have demonstrated that basic physiological changes occur in humans during space flight. These changes include cephalic fluid shifts, loss of fluid and electrolytes, loss of muscle mass, space motion sickness, anemia, reduced immune response, and loss of calcium and mineralized bone. The cause of most of these manifestations is not known and until recently, the general approach was to investigate general systemic changes, not basic cellular responses to microgravity. Recently analyzed data from the 1973-1974 Skylabs disclose that there is a rise in the systemic hormone, cortisol, which may play a role in bone loss in flight. In two flights where bone growth was measured (Skylabs 3 and 4), the crew members had a significant loss of calcium accompanied by a rise in 24 hour urinary cortisol during the entire flight period. In ground-based work on osteoblasts, we have demonstrated that equivalent amounts of glucocorticoids can inhibit osteoblast cell growth. In addition, this laboratory has recently studied gene growth and activation of mouse osteoblasts (MC3T3-E1) during spaceflight. Osteoblast cells were grown on glass coverslips, loaded in the Biorack plunger boxes 18 hours before launch and activated 19 hours after launch in the Biorack incubator under microgravity conditions. The osteoblasts were launched in a serum deprived state, activated and collected in microgravity. Samples were collected at 29 hours after sera activation (0-g, n=4; 1-g, n=4). The osteoblasts were examined for changes in gene expression and cell morphology. Approximately one day after growth activation, remarkable differences were observed in gene expression in 0-g and 1-g flight samples. The 0-g activated cells had increased c-fos mRNA when compared to flight 1-g controls. The message of immediate early growth gene, cox-2 was decreased in the microgravity activated cells when compared to ground or 1-g flight controls. Cox-1 was not

  1. Subjective Straight Ahead Orientation in Microgravity (United States)

    Clement, G.; Reschke, M. F.; Wood, S. J.


    This joint ESA NASA study will address adaptive changes in spatial orientation related to the subjective straight ahead and the use of a vibrotactile sensory aid to reduce perceptual errors. The study will be conducted before and after long-duration expeditions to the International Space Station (ISS) to examine how spatial processing of target location is altered following exposure to microgravity. This study addresses the sensorimotor research gap to "determine the changes in sensorimotor function over the course of a mission and during recovery after landing."

  2. Microgravity cultivation of cells and tissues (United States)

    Freed, L. E.; Pellis, N.; Searby, N.; de Luis, J.; Preda, C.; Bordonaro, J.; Vunjak-Novakovic, G.


    In vitro studies of cells and tissues in microgravity, either simulated by cultivation conditions on earth or actual, during spaceflight, are expected to help identify mechanisms underlying gravity sensing and transduction in biological organisms. In this paper, we review rotating bioreactor studies of engineered skeletal and cardiovascular tissues carried out in unit gravity, a four month long cartilage tissue engineering study carried out aboard the Mir Space Station, and the ongoing laboratory development and testing of a system for cell and tissue cultivation aboard the International Space Station.

  3. Overview of NASA's Microgravity Materials Research Program (United States)

    Downey, James Patton; Grugel, Richard


    The NASA microgravity materials program is dedicated to conducting microgravity experiments and related modeling efforts that will help us understand the processes associated with the formation of materials. This knowledge will help improve ground based industrial production of such materials. The currently funded investigations include research on the distribution of dopants and formation of defects in semiconductors, transitions between columnar and dendritic grain morphology, coarsening of phase boundaries, competition between thermally and kinetically favored phases, and the formation of glassy vs. crystalline material. NASA microgravity materials science investigators are selected for funding either through a proposal in response to a NASA Research Announcement or by participation in a team proposing to a foreign agency research announcement. In the latter case, a US investigator participating in a successful proposal to a foreign agency can then apply to NASA for funding of an unsolicited proposal. The program relies on cooperation with other aerospace partners from around the world. The ISS facilities used for these investigations are provided primarily by partnering with foreign agencies and in most cases the US investigators are working as a part of a larger team studying a specific area of materials science. The following facilities are to be utilized for the initial investigations. The ESA provided Low Gradient Facility and the Solidification and Quench Inserts to the Materials Research Rack/Materials Science Laboratory are to be used primarily for creating bulk samples that are directionally solidified or quenched from a high temperature melt. The CNES provided DECLIC facility is used to observe morphological development in transparent materials. The ESA provided Electro-Magnetic Levitator (EML) is designed to levitate, melt and then cool samples in order to study nucleation behavior. The facility provides conditions in which nucleation of the solid is

  4. Calcium signaling in plant cells in microgravity (United States)

    Kordyum, E.

    Changes in the intracellular Ca 2 + concentration in altered gravity (microgravity and clinostating) evidence that Ca2 + signaling can play a fundamental role in biological effects of microgravity. Calcium as a second messenger is known to play a crucial role in stimulus - response coupling for many plant cellular signaling pathways. Its messenger functions are realized by transient changes in the cytosolic ion concentration induced by a variety of internal and external stimuli such as light, hormones, temperature, anoxia, salinity, and gravity. Although the first data on the changes in the calcium balance in plant cells under the influence of altered gravity have appeared in eighties, a review highlighting the performed research and the possible significance of such Ca 2 + changes in the structural and metabolic rearrangements of plant cells in altered gravity is still lacking. In this paper, an attempt was made to summarize the available experimental results and to consider some hypotheses in this field of research. It is proposed to distinguish between cell gravisensing and cell graviperception; the former is related to cell structure and metabolism stability in the gravitational field and their changes in microgravity (cells not specialized to gravity perception), the latter is related to active use of a gravitational stimulus by cells presumably specialized to gravity perception for realization of normal space orientation, growth, and vital activity (gravitropism, gravitaxis) in plants. The main experimental data concerning both redistribution of free Ca 2 + ions in plant cell organelles and the cell wall, and an increase in the intracellular Ca 2+ concentration under the influence of altered gravity are presented. Based on the gravitational decompensation hypothesis, the consequence of events occurring in gravis ensing cells not specialized to gravity perception under altered gravity are considered in the following order: changes in the cytoplasmic membrane

  5. Cleaner Vacuum-Bag Curing (United States)

    Clemons, J. M.; Penn, B. G.; Ledbetter, Frank E., III; Daniels, J. G.


    Improvement upon recommended procedures saves time and expense. Autoclave molding in vacuum bag cleaner if adhesive-backed covering placed around caul plate as well as on mold plate. Covering easy to remove after curing and leaves caul plate free of resin deposits.

  6. Brine Distribution after Vacuum Saturation

    DEFF Research Database (Denmark)

    Hedegaard, Kathrine; Andersen, Bertel Lohmann


    Experiments with the vacuum saturation method for brine in plugs of chalk showed that a homogeneous distribution of brine cannot be ensured at saturations below 20% volume. Instead of a homogeneous volume distribution the brine becomes concentrated close to the surfaces of the plugs...

  7. Quantum Vacuum Structure and Cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Rafelski, Johann; Labun, Lance; Hadad, Yaron; /Arizona U. /Munich U.; Chen, Pisin; /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC


    Contemporary physics faces three great riddles that lie at the intersection of quantum theory, particle physics and cosmology. They are: (1) The expansion of the universe is accelerating - an extra factor of two appears in the size; (2) Zero-point fluctuations do not gravitate - a matter of 120 orders of magnitude; and (3) The 'True' quantum vacuum state does not gravitate. The latter two are explicitly problems related to the interpretation and the physical role and relation of the quantum vacuum with and in general relativity. Their resolution may require a major advance in our formulation and understanding of a common unified approach to quantum physics and gravity. To achieve this goal we must develop an experimental basis and much of the discussion we present is devoted to this task. In the following, we examine the observations and the theory contributing to the current framework comprising these riddles. We consider an interpretation of the first riddle within the context of the universe's quantum vacuum state, and propose an experimental concept to probe the vacuum state of the universe.

  8. LEP vacuum chamber, early prototype

    CERN Multimedia

    CERN PhotoLab


    The same vacuum chamber as in 7810256, read the detailed description there. Here, the 4 strip-shaped ion-getter pumps are poised at the entrance to their slots. Ion-getter pumps were not retained, thermal getter pumps were chosen instead (see 8301153 and 8305170).

  9. Filling the vacuum at LHCb

    CERN Multimedia

    Katarina Anthony


    Last month, the Vacuum, Surfaces and Coatings (VSC) group was tasked with an unusually delicate operation in the LHCb experiment cavern: removing the LHC beam pipe while keeping the sensitive Vertex Locator vacuum vessel (VELO) completely isolated from the action.   The VSC group seal off the VELO beam pipe with a flange. Image: Gloria Corti. LHCb’s VELO detector is one of the crown jewels of the experiment. With detector elements surrounded by a vacuum, it gets as close as 5 cm from the beam. Fantastic for physics, but difficult for all-important access. “Because of the sensitivity of the VELO detector and its proximity to the beam, the collaboration decided not to bake (see box) its portion of the beam pipe,” says Giulia Lanza (TE-VSC-LBV), the expert in charge of the beam vacuum operation. “Our group was therefore asked to remove the rest of the LHC beam pipe while keeping the VELO portion of the pipe completely isolated. This work...

  10. Vacuum Stability of Standard Model^{++}

    CERN Document Server

    Anchordoqui, Luis A.; Goldberg, Haim; Huang, Xing; Lust, Dieter; Taylor, Tomasz R.; Vlcek, Brian


    The latest results of the ATLAS and CMS experiments point to a preferred narrow Higgs mass range (m_h \\simeq 124 - 126 GeV) in which the effective potential of the Standard Model (SM) develops a vacuum instability at a scale 10^{9} -10^{11} GeV, with the precise scale depending on the precise value of the top quark mass and the strong coupling constant. Motivated by this experimental situation, we present here a detailed investigation about the stability of the SM^{++} vacuum, which is characterized by a simple extension of the SM obtained by adding to the scalar sector a complex SU(2) singlet that has the quantum numbers of the right-handed neutrino, H", and to the gauge sector an U(1) that is broken by the vacuum expectation value of H". We derive the complete set of renormalization group equations at one loop. We then pursue a numerical study of the system to determine the triviality and vacuum stability bounds, using a scan of 10^4 random set of points to fix the initial conditions. We show that, if there...

  11. Vacuum assisted closure in coloproctology

    NARCIS (Netherlands)

    Bemelman, W.A.


    Vacuum-assisted closure has earned its indications in coloproctology. It has been described with variable results in the treatment of large perineal defects after abdominoperineal excision, in the treatment of stoma dehiscence and perirectal abscesses. The most promising indication for

  12. Computational fluid dynamics simulations of a glass melting furnace

    Energy Technology Data Exchange (ETDEWEB)

    Egelja, A.; Lottes, S. A.


    The glass production industry is one of the major users of natural gas in the US, and approximately 75% of the energy produced from natural gas is used in the melting process. Industrial scale glass melting furnaces are large devices, typically 5 or more meters wide, and twice as long. To achieve efficient heat transfer to the glass melt below, the natural gas flame must extend over a large portion of the glass melt. Therefore modern high efficiency burners are not used in these furnaces. The natural gas is injected as a jet, and a jet flame forms in the flow of air entering the furnace. In most current glass furnaces the energy required to melt the batch feed stock is about twice the theoretical requirement. An improved understanding of the heat transfer and two phase flow processes in the glass melt and solid batch mix offers a substantial opportunity for energy savings and consequent emission reductions. The batch coverage form and the heat flux distribution have a strong influence on the glass flow pattern. This flow pattern determines to a significant extent the melting rate and the quality of glass.

  13. Heuristic algorithms for scheduling heat-treatment furnaces of steel ...

    Indian Academy of Sciences (India)

    treatment furnaces in a steel-casting foundry, a special problem of batch processor scheduling, ... production management is to maximize throughput and reduce flow time and WIP. This motivated the choice of ..... A computational experiment is appropriate in order to provide a perspective on the relative effectiveness of any ...

  14. Reliability of graphite furnace atomic absorption spectrometry as ...

    African Journals Online (AJOL)

    Purpose: To evaluate the comparative efficiency of graphite furnace atomic absorption spectrometry (GFAAS) and hydride generation atomic absorption spectrometry (HGAAS) for trace analysis of arsenic (As) in natural herbal products (NHPs). Method: Arsenic analysis in natural herbal products and standard reference ...

  15. Optimization of burners in oxygen-gas fired glass furnace

    NARCIS (Netherlands)

    Kersbergen, M.J. van; Beerkens, R.G.C.; Sarmiento-Darkin, W.; Kobayashi, H.


    The energy efficiency performance, production stability and emissions of oxygen-fired glass furnaces are influenced by the type of burner, burner nozzle sizes, burner positions, burner settings, oxygen-gas ratios and the fuel distribution among all the burners. These parameters have been optimized

  16. Analysis of combustion efficiency in a pelletizing furnace

    Directory of Open Access Journals (Sweden)

    Rafael Simões Vieira de Moura

    Full Text Available Abstract The objective of this research is to assess how much the improvement in the combustion reaction efficiency can reduce fuel consumption, maintaining the same thermal energy rate provided by the reaction in a pelletizing furnace. The furnace for pelletizing iron ore is a complex thermal machine, in terms of energy balance. It contains recirculation fan gases and constant variations in the process, and the variation of a single process variable can influence numerous changes in operating conditions. This study demonstrated how the main variables related to combustion in the burning zone influence fuel consumption (natural gas from the furnace of the Usina de Pelotização de Fábrica (owned by VALE S/A, without changing process conditions that affect production quality. Variables were analyzed regarding the velocity and pressure of the fuel in the burners, the temperature of the combustion air and reactant gases, the conversion rate and the stoichiometric air/fuel ratio of the reaction. For the analysis, actual data of the furnace in operation was used, and for the simulation of chemical reactions, the software Gaseq® was used. The study showed that the adjustment of combustion reaction stoichiometry provides a reduction of 9.25% in fuel consumption, representing a savings of US$ 2.6 million per year for the company.

  17. Chloride ingress of carbonated blast furnace slag cement mortars

    NARCIS (Netherlands)

    Holthuizen, P.E.; Çopuroglu, O.; Polder, R.B.


    In the Netherlands civil engineering structures, such as overpasses, bridges and tunnels are generally built using blast furnace slag cement (BFSC, CEM III/B) concrete, because of its high resistance against chloride penetration. Although the Dutch experience regarding durability performance of BFSC

  18. Heuristic algorithms for scheduling heat-treatment furnaces of steel ...

    Indian Academy of Sciences (India)

    The scheduling of furnaces for heat-treatment of castings is of considerable interest as a large proportion of the total production time is the processing times of these ... Department of Management Studies, Indian Institute of Science, Bangalore 560 012; Singapore-MIT Alliance, School of Mechanical and Aerospace ...

  19. Reliability of graphite furnace atomic absorption spectrometry as ...

    African Journals Online (AJOL)

    Original Research Article. Reliability of graphite furnace atomic absorption spectrometry as alternative method for trace analysis of arsenic in natural medicinal products. Reem Saadi Khalid1*, ABM Helaluddin1, Reem Saadi Khalid1, Mohamed. Alaama1, Abdualrahman M Abdualkader1, Abdulrazak Kasmuri2 and Syed Atif.


    Directory of Open Access Journals (Sweden)

    A. B. Steblov


    Full Text Available Investigations have shown a positive impact of increasing the mass of the liquid residue (swamps in an electric arc furnace EAF-160, from 10 to 20–30 tonnes on increasing of usable output and reducing the specific energy consumption per ton of liquid metal.

  1. Analysis of a furnace for heat generation using polydisperse biomass

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, Edney Alves; Silva, Juarez de Sousa e; Silva, Jadir Nogueira da; Oliveira Filho, Delly [Universidade Federal de Vicosa (DEA/UFV), MG (Brazil). Dept. de Engenharia Agricola; Donzeles, Sergio Mauricio Lopes [Empresa de Pesquisa Agropecuaria de Minas Gerais (EPAMIG), Vicosa, MG (Brazil)


    In many agro-industrial activities, the processing of raw material generates a substantial amount of fine materials. Examples include the production of soluble coffee, processing of rice, and wood processing, among others. In many regions, these by-products keep piling up on the courtyard of companies or become an environmental problem for land dumps. However, detailed tests of these byproducts indicate that they are excellent sources of energy. With this in mind, a furnace was developed to generate clean and hot air, using the alimentation system for pneumatic transport. Wood sawdust was used as fuel for analysis. The obtained results were considered satisfactory, proven by the small heat losses, primarily by the non-burned carbon monoxide (less than 0.2%) and the cooling of the furnace (less than 2.5%) whereas the losses by the exhaust gases were a little more than 23%. The thermal efficiency of the furnace was considered high when compared to others with an indirect heating system, obtaining an average value of 73%. The developed furnace, beyond being efficient, allows the use of the waste from the wood industry, which is important in the reduction of environmental impacts and minimizing production costs associated with the acquisition of conventional energy. (author)

  2. Electrode immersion depth determination and control in electroslag remelting furnace

    Energy Technology Data Exchange (ETDEWEB)

    Melgaard, David K. (Albuquerque, NM); Beaman, Joseph J. (Austin, TX); Shelmidine, Gregory J. (Tijeras, NM)


    An apparatus and method for controlling an electroslag remelting furnace comprising adjusting electrode drive speed by an amount proportional to a difference between a metric of electrode immersion and a set point, monitoring impedance or voltage, and calculating the metric of electrode immersion depth based upon a predetermined characterization of electrode immersion depth as a function of impedance or voltage.


    Directory of Open Access Journals (Sweden)

    S. L. Rovin


    Full Text Available The article presents the results of computer simulation of dispersed materials motion in rotary furnaces with an inclined axis of rotation. Has been received new data on the dynamic layer work that enhances understanding of heat and mass transfer processes occurring in the layer. 


    Directory of Open Access Journals (Sweden)

    S. L. Rovin


    Full Text Available The article is devoted to research of process of the iron-containing waste recycling in rotary tilting furnaces, in particular, to the phenomenon of formation of ball iron at transition from hard-phase to liquid-phase stage of iron restoration from scale.

  5. Utilization of steel melting electric arc furnace slag for development ...

    Indian Academy of Sciences (India)

    ... but generates a new waste, electric arc furnace slag, which is getting accumulated and land/mine filling and road construction are the only utilization. This slag has been tried to be value added and utilized to develop vitreous ceramic tiles. Slag, to the extent of 30–40 wt% with other conventional raw materials, were used ...


    This document is an evaluation of the performance of the Babcock & Wilcox (B&W) Cyclone Furnace Vitrification Technology and its applicability as a treatment technique for soils contaminated with heavy metals, radionuclides, and organics. oth the technical and economic aspects of...

  7. Sliding mode controllers for a tempered glass furnace. (United States)

    Almutairi, Naif B; Zribi, Mohamed


    This paper investigates the design of two sliding mode controllers (SMCs) applied to a tempered glass furnace system. The main objective of the proposed controllers is to regulate the glass plate temperature, the upper-wall temperature and the lower-wall temperature in the furnace to a common desired temperature. The first controller is a conventional sliding mode controller. The key step in the design of this controller is the introduction of a nonlinear transformation that maps the dynamic model of the tempered glass furnace into the generalized controller canonical form; this step facilitates the design of the sliding mode controller. The second controller is based on a state-dependent coefficient (SDC) factorization of the tempered glass furnace dynamic model. Using an SDC factorization, a simplified sliding mode controller is designed. The simulation results indicate that the two proposed control schemes work very well. Moreover, the robustness of the control schemes to changes in the system's parameters as well as to disturbances is investigated. In addition, a comparison of the proposed control schemes with a fuzzy PID controller is performed; the results show that the proposed SDC-based sliding mode controller gave better results. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  8. Analyses of laser and furnace treated sol-gel coatings

    NARCIS (Netherlands)

    De Hosson, JT; De Haas, M; Sudarshan, TS; Jeandin, M; Khor, KA


    Here we explore a new method that allows thin films to be made with almost any composition and degree of porosity by means of a combination of sol-gel and laser technology. Results are presented for furnace and laser treated TEOTI-(tetraethylorthotitanate as sol precursor) coated silicon samples.


    Energy Technology Data Exchange (ETDEWEB)

    William S. McPhee


    The objective of this project is to improve the productivity and lower the expense of existing vacuum blasting technology. This technology is used to remove radioactive contamination, PCBs, and lead-based paint and provides worker protection by continuously recycling the material and dust for the decontamination tasks. The proposed work would increase the cleaning rate and provide safe and cost-effective decontamination of the DOE sites. This work focuses on redesigning and improving existing vacuum blasting technology including blast head nozzles, ergonomic handling of the blast head by reducing its weight; brush-ring design, vacuum level regulator, efficiency of the dust separator, and operational control sensors. The redesign is expected to enhance the productivity and economy of the vacuum blasting system by at least 50% over current vacuum blasting systems. There are three phases in the project. Phase I consists of developing and testing mathematical models. Phase II consists of pre-prototype design and fabrication and pre-prototype unit testing. Phase III consists of prototype design and field verification testing. In phase I, mathematical models are developed and analyzed for the nozzle, blast head, wind curtain, and dust separator, first as individual devices and then combined as an integrated model. This allows study of respective airflow and design parameters. The Contractor shall, based on the results of the mathematical modeling studies, design experimental models of the components and test these models. In addition, the Contractor shall develop sensors to detect the relationship of the blast head to the blast surfaces and controls to minimize the dependency on an operator's skill and judgment to obtain optimum positioning, as well as real-time characterization sensors to determine as the blast head is moving the depth to which coatings must be removed, thereby improving production and minimizing waste. In phase II, the Contractor shall design and

  10. Brayton-Cycle Heat Recovery System Characterization Program. Glass-furnace facility test plan

    Energy Technology Data Exchange (ETDEWEB)


    The test plan for development of a system to recover waste heat and produce electricity and preheated combustion air from the exhaust gases of an industrial glass furnace is described. The approach is to use a subatmospheric turbocompressor in a Brayton-cycle system. The operational furnace test requirements, the operational furnace environment, and the facility design approach are discussed. (MCW)

  11. 46 CFR 59.15-5 - Stayed furnaces and combustion chambers. (United States)


    ... 46 Shipping 2 2010-10-01 2010-10-01 false Stayed furnaces and combustion chambers. 59.15-5 Section... and combustion chambers. (a) Where the plate forming the walls of stayed furnaces or combustion... wall of a stayed furnace or combustion chamber, the defective portion of the plate shall be cut away...

  12. Vacuum polarization and Hawking radiation (United States)

    Rahmati, Shohreh

    Quantum gravity is one of the interesting fields in contemporary physics which is still in progress. The purpose of quantum gravity is to present a quantum description for spacetime at 10-33cm or find the 'quanta' of gravitational interaction.. At present, the most viable theory to describe gravitational interaction is general relativity which is a classical theory. Semi-classical quantum gravity or quantum field theory in curved spacetime is an approximation to a full quantum theory of gravity. This approximation considers gravity as a classical field and matter fields are quantized. One interesting phenomena in semi-classical quantum gravity is Hawking radiation. Hawking radiation was derived by Stephen Hawking as a thermal emission of particles from the black hole horizon. In this thesis we obtain the spectrum of Hawking radiation using a new method. Vacuum is defined as the possible lowest energy state which is filled with pairs of virtual particle-antiparticle. Vacuum polarization is a consequence of pair creation in the presence of an external field such as an electromagnetic or gravitational field. Vacuum polarization in the vicinity of a black hole horizon can be interpreted as the cause of the emission from black holes known as Hawking radiation. In this thesis we try to obtain the Hawking spectrum using this approach. We re-examine vacuum polarization of a scalar field in a quasi-local volume that includes the horizon. We study the interaction of a scalar field with the background gravitational field of the black hole in the desired quasi-local region. The quasi-local volume is a hollow cylinder enclosed by two membranes, one inside the horizon and one outside the horizon. The net rate of particle emission can be obtained as the difference of the vacuum polarization from the outer boundary and inner boundary of the cylinder. Thus we found a new method to derive Hawking emission which is unitary and well defined in quantum field theory.

  13. Silicide formation by furnace annealing of thin Si films on large-grained Ni substrates (United States)

    Brunner, A. J.; Ma, E.; Nicolet, M.-A.


    Si films with a thickness of approximately 250 nm have been electron-beam evaporated on thick, large-grained Ni substrates (grain size a few mm to 1 cm in diameter). An in situ sputter cleaning procedure has been used to clean the Ni surface before the Si deposition. Thermal annealings have been performed in a vacuum furnace. Ni2Si is the first phase that grows at temperatures between 240 °C and 300 °C as a laterally uniform interfacial layer with a diffusion-controlled kinetics. The layer thickness x follows the growth law x 2= kt, with k=k 0 exp(- E a k B T), where k 0=6.3 × 10-4cm 2/s and E a=(1-1±0.1) eV. Because of the virtually infinite supply of Ni, annealing at 800 °C for 130min yields a Ni-based solid solution as the final phase. The results are compared with those reported in the literature on suicide formation by the reaction of a thin Ni film on Si substrates, as well as with those for interfacial phase formation in Ni/Zr bilayers.

  14. Collective search by ants in microgravity

    Directory of Open Access Journals (Sweden)

    Stefanie M. Countryman


    Full Text Available The problem of collective search is a tradeoff between searching thoroughly and covering as much area as possible. This tradeoff depends on the density of searchers. Solutions to the problem of collective search are currently of much interest in robotics and in the study of distributed algorithms, for example to design ways that without central control robots can use local information to perform search and rescue operations. Ant colonies operate without central control. Because they can perceive only local, mostly chemical and tactile cues, they must search collectively to find resources and to monitor the colony's environment. Examining how ants in diverse environments solve the problem of collective search can elucidate how evolution has led to diverse forms of collective behavior. An experiment on the International Space Station in January 2014 examined how ants (Tetramorium caespitum perform collective search in microgravity. In the ISS experiment, the ants explored a small arena in which a barrier was lowered to increase the area and thus lower ant density. In microgravity, relative to ground controls, ants explored the area less thoroughly and took more convoluted paths. It appears that the difficulty of holding on to the surface interfered with the ants’ ability to search collectively. Ants frequently lost contact with the surface, but showed a remarkable ability to regain contact with the surface.

  15. NMR assessment on bone simulated under microgravity (United States)

    Ni, Q.; Qin, Y.

    Introduction Microgravity-induced bone loss has been suggested to be similar to disuse-osteoporosis on Earth which constitutes a challenging public health problem No current non-destructive method can provide the microstructural changes in bone particularly on cortical bone Recently the authors have applied low field nuclear magnetic resonance NMR spin-spin relaxation technique and computational analysis method to determine the porosity pore size distribution and microdamage of cortical bone 1-3 The studies by the authors have shown that this technology can be used to characterize microstructural changes as well as bone water distribution bound and mobile water changes of weightless treated simulating a microgravity condition turkey and mouse cortical bone We further determinate that the NMR spin-spin relaxation time T 2 spectrum derived parameters can be used as descriptions of bone quality e g matrix water distribution and porosity size distributions and alone or in combination with current techniques bone mineral density measurements more accurately predict bone mechanical properties Methods underline Bone sample preparation Two kinds of animal samples were collected and prepared for designed experiments from SUNY Cortical bones of the mid-diaphyses of the ulnae of 1-year-old male turkeys were dissected from freshly slaughtered animals Eight samples were categorized from normal or control and four samples were 4-week disuse treated by functionally isolated osteotomies disuse A total of 12

  16. Biotechnology Facility: An ISS Microgravity Research Facility (United States)

    Gonda, Steve R.; Tsao, Yow-Min


    The International Space Station (ISS) will support several facilities dedicated to scientific research. One such facility, the Biotechnology Facility (BTF), is sponsored by the Microgravity Sciences and Applications Division (MSAD) and developed at NASA's Johnson Space Center. The BTF is scheduled for delivery to the ISS via Space Shuttle in April 2005. The purpose of the BTF is to provide: (1) the support structure and integration capabilities for the individual modules in which biotechnology experiments will be performed, (2) the capability for human-tended, repetitive, long-duration biotechnology experiments, and (3) opportunities to perform repetitive experiments in a short period by allowing continuous access to microgravity. The MSAD has identified cell culture and tissue engineering, protein crystal growth, and fundamentals of biotechnology as areas that contain promising opportunities for significant advancements through low-gravity experiments. The focus of this coordinated ground- and space-based research program is the use of the low-gravity environment of space to conduct fundamental investigations leading to major advances in the understanding of basic and applied biotechnology. Results from planned investigations can be used in applications ranging from rational drug design and testing, cancer diagnosis and treatments and tissue engineering leading to replacement tissues.

  17. Resource Management in the Microgravity Science Division (United States)

    Casselle, Justine


    In the Microgravity Science Division, the primary responsibilities of the Business Management Office are resource management and data collection. Resource management involves working with a budget to do a number of specific projects, while data collection involves collecting information such as the status of projects and workforce hours. This summer in the Business Management Office I assisted Margie Allen with resource planning and the implementation of specific microgravity projects. One of the main duties of a Project Control Specialists, such as my mentor, is to monitor and analyze project manager s financial plans. Project managers work from the bottom up to determine how much money their project will cost. They then set up a twelve month operating plan which shows when money will be spent. I assisted my mentor in checking for variances in her data against those of the project managers. In order to successfully check for those variances, we had to understand: where the project is including plans vs. actual performance, why it is in its present condition, and what the future impact will be based on known budgetary parameters. Our objective was to make sure that the plan, or estimated resources input, are a valid reflection of the actual cost. To help with my understanding of the process, over the course of my tenure I had to obtain skills in Microsoft Excel and Microsoft Access.

  18. Planarians Sense Simulated Microgravity and Hypergravity

    Directory of Open Access Journals (Sweden)

    Teresa Adell


    Full Text Available Planarians are flatworms, which belong to the phylum Platyhelminthes. They have been a classical subject of study due to their amazing regenerative ability, which relies on the existence of adult totipotent stem cells. Nowadays they are an emerging model system in the field of developmental, regenerative, and stem cell biology. In this study we analyze the effect of a simulated microgravity and a hypergravity environment during the process of planarian regeneration and embryogenesis. We demonstrate that simulated microgravity by means of the random positioning machine (RPM set at a speed of 60 °/s but not at 10 °/s produces the dead of planarians. Under hypergravity of 3 g and 4 g in a large diameter centrifuge (LDC planarians can regenerate missing tissues, although a decrease in the proliferation rate is observed. Under 8 g hypergravity small planarian fragments are not able to regenerate. Moreover, we found an effect of gravity alterations in the rate of planarian scission, which is its asexual mode of reproduction. No apparent effects of altered gravity were found during the embryonic development.

  19. Planarians sense simulated microgravity and hypergravity. (United States)

    Adell, Teresa; Saló, Emili; van Loon, Jack J W A; Auletta, Gennaro


    Planarians are flatworms, which belong to the phylum Platyhelminthes. They have been a classical subject of study due to their amazing regenerative ability, which relies on the existence of adult totipotent stem cells. Nowadays they are an emerging model system in the field of developmental, regenerative, and stem cell biology. In this study we analyze the effect of a simulated microgravity and a hypergravity environment during the process of planarian regeneration and embryogenesis. We demonstrate that simulated microgravity by means of the random positioning machine (RPM) set at a speed of 60 °/s but not at 10 °/s produces the dead of planarians. Under hypergravity of 3 g and 4 g in a large diameter centrifuge (LDC) planarians can regenerate missing tissues, although a decrease in the proliferation rate is observed. Under 8 g hypergravity small planarian fragments are not able to regenerate. Moreover, we found an effect of gravity alterations in the rate of planarian scission, which is its asexual mode of reproduction. No apparent effects of altered gravity were found during the embryonic development.

  20. Microgravity sciences application visiting scientist program (United States)


    Contract NAS8-38785, Microgravity Experimental and Theoretical Research, is a project involving a large number of individual research programs related to: determination of the structure of human serum albumin and other biomedically important proteins; analysis of thermodynamic properties of various proteins and models of protein nucleation; development of experimental techniques for the growth of protein crystals in space; study of the physics of electrical double layers in the mechanics of liquid interfaces; computational analysis of vapor crystal growth processes in microgravity; analysis of the influence of magnetic fields in damping residual flows in directional solidification processes; crystal growth and characterization of II-VI semiconductor alloys; and production of thin films for nonlinear optics. It is not intended that the programs will be necessarily limited to this set at any one time. The visiting scientists accomplishing these programs shall serve on-site at MSFC to take advantage of existing laboratory facilities and the daily opportunities for technical communications with various senior scientists.

  1. Gravitational Waves in Decaying Vacuum Cosmologies


    David Alejandro Tamayo Ramirez


    In the present monograph we study in detail the primordial gravitational waves in cosmologies with a decaying vacuum. The decaying vacuum models are an alternative to solve the cosmological constant problem attributing a dynamic to the vacuum energy. The problem of primordial gravitational waves is discussed in the framework of an expanding, flat, spatially homogeneous and isotropic FLRW Universe described by General Relativity theory with decaying vacuum energy density of the type $\\\\Lambda ...

  2. Robot Vacuum Cleaner Personality and Behavior


    Hendriks, A.F.M.; Meerbeek, B.W.; Boess, S.; Pauws, S.C.; Sonneveld, M.


    In this paper we report our study on the user experience of robot vacuum cleaner behavior. How do people want to experience this new type of cleaning appliance? Interviews were conducted to elicit a desired robot vacuum cleaner personality. With this knowledge in mind, behavior was designed for a future robot vacuum cleaner. A video prototype was used to evaluate how people experienced the behavior of this robot vacuum cleaner. The results indicate that people recognizedthe intended personali...

  3. Media Compositions for Three Dimensional Mammalian Tissue Growth Under Microgravity Culture Conditions (United States)

    Goodwin, Thomas J. (Inventor)


    Normal mammalian tissue and the culturing process has been developed for the three groups of organ, structural and blood tissue. The cells are grown in vitro under microgravity culture conditions and form three dimensional cells aggregates with normal cell function. The microgravity culture conditions may be microgravity or simulated microgravity created in a horizontal rotating wall culture vessel.

  4. Media Compositions for Three-Dimensional Mammalian Tissue Growth under Microgravity Culture Conditions (United States)

    Goodwin, Thomas J. (Inventor)


    Normal mammalian tissue and the culturing process has been developed for the three groups of organ, structural and blood tissue.The cells are grown in vitro under microgravity culture conditions and form three dimensional cells aggregates with normal cell function. The microgravity culture conditions may be microgravity or simulated microgravity created in a horizontal rotating wall culture vessel.

  5. Microgravity-Enhanced Stem Cell Selection (United States)

    Claudio, Pier Paolo; Valluri, Jagan


    Stem cells, both embryonic and adult, promise to revolutionize the practice of medicine in the future. In order to realize this potential, a number of hurdles must be overcome. Most importantly, the signaling mechanisms necessary to control the differentiation of stem cells into tissues of interest remain to be elucidated, and much of the present research on stem cells is focused on this goal. Nevertheless, it will also be essential to achieve large-scale expansion and, in many cases, assemble cells in 3D as transplantable tissues. To this end, microgravity analog bioreactors can play a significant role. Microgravity bioreactors were originally conceived as a tool to study the cellular responses to microgravity. However, the technology can address some of the shortcomings of conventional cell culture systems; namely, the deficiency of mass transport in static culture and high mechanical shear forces in stirred systems. Unexpectedly, the conditions created in the vessel were ideal for 3D cell culture. Recently, investigators have demonstrated the capability of the microgravity bioreactors to expand hematopoietic stem cells compared to static culture, and facilitate the differentiation of umbilical cord stem cells into 3D liver aggregates. Stem cells are capable of differentiating into functional cells. However, there are no reliable methods to induce the stem cells to form specific cells or to gain enough cells for transplantation, which limits their application in clinical therapy. The aim of this study is to select the best experimental setup to reach high proliferation levels by culturing these cells in a microgravity-based bioreactor. In typical cell culture, the cells sediment to the bottom surface of their container and propagate as a one-cell-layer sheet. Prevention of such sedimentation affords the freedom for self-assembly and the propagation of 3D tissue arrays. Suspension of cells is easily achievable using stirred technologies. Unfortunately, in

  6. 14 CFR 29.1433 - Vacuum systems. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe...

  7. Utilize Vacuum Forming to Make Interdisciplinary Connections (United States)

    Love, Tyler S.; Valenza, Frank


    The concept of vacuum forming has been around since the 19th century, despite not being fully utilized in industry until the 1950s. In the past, industrial arts classes have used vacuum-forming projects to concentrate solely on the manufacturing process and the final product. However, vacuum forming is not just an old industrial arts activity; it…

  8. 14 CFR 25.1433 - Vacuum systems. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe. ...

  9. The Dirac-Electron Vacuum Wave

    Directory of Open Access Journals (Sweden)

    Daywitt W. C.


    Full Text Available This paper argues that the Dirac equation can be interpreted as an interaction between the electron core and the Planck vacuum state, where the positive and negative solutions represent respectively the dynamics of the electron core and a vacuum wave propagating within the vacuum state. Results show that the nonrelativistic positive solution reduces to the Schrödinger wave equation

  10. Flame Shapes of Fuel Droplet Could in High Temperature Gaseous Environment under Micro-gravity (United States)

    Enomoto, Hiroshi; Nagata, Hitoshi; Segawa, Daisuke; Kadota, Toshikazu

    In order to investigate the spray combustion mechanism, a new methodology (Fine Wire Sustaining method) was established. Fine wires of 14µm in diameter were used to sustain the droplets. Any arrangement of the droplets could be performed with this method. In this study, 33 fuel droplets arranged in symmetrically were subjected to the quiescent high temperature air in an electric furnace. The temperature of the environment air was about 1000K. Fuel was n-eicosane and the mean droplet diameter was 0.58mm. The standard deviation of the droplet diameter was 0.02mm. A high-speed video camera of 250ftp was provided to observe the auto-ignition and flames of fuel droplet clouds. The experiments were done at atmospheric pressure using the JAMIC drop shaft that provides 10 seconds of effective period of time for the micro-gravity. As the results, the time histories of the diameter of the particle flames had maximum and that of the diameter of the group flame had the minimum.

  11. Influence of Containment on the Growth of Germanium-Silicon in Microgravity (United States)

    Volz, M. P.; Mazuruk, K.; Croll, A.; Sorgenfrei, T.


    A series of Ge(sub 1-x)Si(sub x) crystal growth experiments are planned to be conducted in the Low Gradient Furnace (LGF) onboard the International Space Station. The primary objective of the research is to determine the influence of containment on the processing-induced defects and impurity incorporation in germanium-silicon alloy crystals. A comparison will be made between crystals grown by the normal and 'detached' Bridgman methods and the ground-based float zone technique. 'Detached' or 'dewetted' Bridgman growth is similar to regular Bridgman growth in that most of the melt is in contact with the crucible wall, but the crystal is separated from the wall by a small gap, typically of the order of 10-100 microns. A meniscus bridges this gap between the top of the crystal and the crucible wall. Theoretical models indicate that an important parameter governing detachment is the pressure differential across this meniscus. An experimental method has been developed to control this pressure differential in microgravity that does not require connection of the ampoule volume to external gases or changes in the temperature profile during growth. Experiments will be conducted with positive, negative or zero pressure differential across the meniscus. Characterization results of ground-based experiments, including etch pit density, synchrotron white beam X-ray topography and double axis X-ray diffraction will also be described.

  12. Metallurgy of mercury in Almaden: from aludel furnaces until Pacific furnaces; La metalurgia del mercurio en Almaden: desde los hornos de aludeles a los hornos Pacific

    Energy Technology Data Exchange (ETDEWEB)

    Tejero-Manzanares, J.; Garrido Saenz, I.; Mata Cabrera, F.; Rubio Mesas, M. L.


    This paper shows the different types of furnaces for roasting cinnabar, used in the metallurgy of quicksilver over the centuries of exploitation of the Almaden Mines (Spain). Some of these techniques are part of our industrial heritage. They have contributed to name UNESCO World Heritage Site the vast technological legacy of these mines recently. This research contributes to close the long way of metallurgical activity from aludel furnaces until Pacif furnaces, first and lasted technology to produce on an industrial scale. It is delved into the most relevant aspects having to do with the type, evolution and number of furnaces existing on each of the periods. (Author)

  13. Numerical Computation of Net Radiative Heat Transfer within a Non Absorbing Furnace Enclosure

    Directory of Open Access Journals (Sweden)

    Shuaibu Ndache MOHAMMED


    Full Text Available The numerical evaluation of the net radiative heat transfer rate in a single zone, non absorbing furnace enclosure is reported. In this analysis, simplified mathematical furnace model namely, the long furnace model is used to determine furnace performance. The formulation assumes some known temperature values. Thus, heat transfer equations were set up and solved numerically. A FORTRAN computer program was developed and debugged. Results obtained from this study compare favourably well with the results from the traditional graphical method. Also, the computer program developed can handle variations in furnace operating conditions, temperatures, thermal properties and dimensions.

  14. The effects of microgravity on gametogenesis, fertilization, and early embryogenesis (United States)

    Tan, X.

    Gametogenesis fertilization and early embryogenesis are crucial periods for normal development afterwards In past three decades many experiments have been conducted in space and in simulated weightlessness induced by clinostats to elucidate the issue Different animal species including Drosophila wasp shrimp fish amphibian mouse rats etc have been used for the study Oogenesis and spermatogenesis are affected by microgravity in different ways Some researches found that microgravity condition perturbed the process of oogenesis in many species A significant increased frequency of chromosomal non-disjunction was found in Drosophila females resulting the loss of chromosomes during meiosis and inhibition of cell division Studies on wasp showed a decreased hatchability and accumulation of unhatched eggs when the insects were exposed to spaceflight at different stages of oogenesis For experiments conducted on vertebrate animal models the results are somehow different however Microgravity has no significant effect for fish Medaka etc amphibian South African clawed toad Xenopus laevis or mammals mouse Spermatogenesis on the other hand is more significantly affected by microgravity condition Some researches indicated sperm are sensitive to changes in gravitational force and this sensitivity affects the ability of sperm to fertilize eggs Sperm swim with higher velocity in microgravity which is coupled with altered protein phosphorylation level in sperm under microgravity condition Microgravity also induced activation of the

  15. Plant reproduction systems in microgravity: experimental data and hypotheses (United States)

    Kordyum, E. L.

    Elucidation of the possibilities for higher plants to realize complete ontogenesis, from seed to seed, and to propagate by seeds in microgravity, is a fundamental task of space biology connected with the working of the CELSS program. At present, there are results of only 6 spaceflight experiments with Arabidopsis thaliana, an ephemeral plant which will flower and fruit in orbit. Morphogenesis of generative organs occurs normally in microgravity, but unlike the ground control, buds and flowers mainly contain sterile elements of the androecium and gynoecium which degenerate at different stages of development in microgravity. Cytological peculiarities of male and female sterility in microgravity are similar to those occurring naturally during sexual differentiation. Many of the seed formed in microgravity are: 1) nutritional deficiency, 2) insufficient light, 3) intensification of the influence of the above-mentioned factors by microgravity, 4) disturbances of a hormonal nature, and 5) the absence of pollination and fertilization. Possible ways for testing these hypotheses and obtaining viable seeds in microgravity are discussed.

  16. "Flat-Fish" Vacuum Chamber

    CERN Multimedia

    CERN PhotoLab


    The picture shows a "Flat-Fish" vacuum chamber being prepared in the ISR workshop for testing prior to installation in the Split Field Magnet (SFM) at intersection I4. The two shells of each part were hydroformed from 0.15 mm thick inconel 718 sheet (with end parts in inconel 600 for easier manual welding to the arms) and welded toghether with two strips which were attached by means of thin stainless steel sheets to the Split Field Magnet poles in order to take the vertical component of the atmospheric pressure force. This was the thinnest vacuum chamber ever made for the ISR. Inconel material was chosen for its high elastic modulus and strenght at chamber bake-out temperature. In this picture the thin sheets transferring the vertical component of the atmosferic pressure force are attached to a support frame for testing. See also 7712182, 7712179.

  17. Advanced window incorporating vacuum glazing (United States)

    Asano, Osamu; Misonou, Masao; Kato, Hidemi; Nagasaka, Shigeki


    Vacuum glazing product named SPACIATM, being an unique product with very high levels of thermal insulation properties in a very small thickness, is described in detail. The construction and manufacturing process of SPACIATM are reported. Its design, which was originally established by R.E. Collins et al. of the University of Sydney, has been adjusted in order to meet the requirements of the Japanese market and the requirements of mass production process. SPACIATM is found to have several unique features including airborne sound insulation as well as thermal insulation. Energy required for air conditioning was simulated for Japanese houses with various glazings, and it was revealed that SPACIATM could save the energy efficiently. Finally, hybrid IG unit, where vacuum glazing is incorporated into a conventional IG unit, is proposed for further improvement of thermal insulation.

  18. LEP vacuum chamber, early prototype

    CERN Multimedia

    CERN PhotoLab


    The structure of LEP, with long bending magnets and little access to the vacuum chamber between them, required distributed pumping. This is an early prototype for the LEP vacuum chamber, made from extruded aluminium. The main opening is for the beam. The small channel to the right is for cooling water, to carry away the heat deposited by the synchroton radiation from the beam. The 4 slots in the channel to the left house the strip-shaped ion-getter pumps (see 7810255). The ion-getter pumps depended on the magnetic field of the bending magnets, too low at injection energy for the pumps to function well. Also, a different design was required outside the bending magnets. This design was therefore abandoned, in favour of a thermal getter pump (see 8301153 and 8305170).

  19. Vacuum Alignment with more Flavors

    DEFF Research Database (Denmark)

    Ryttov, Thomas


    _f=2$ and $N_f=3$ we reproduce earlier known results including the Dashen phase with spontaneous violation of the combined charge conjugation and parity symmetry, CP. For $N_f=4$ we find regions with and without spontaneous CP violation. We then generalize to an arbitrary number of flavors. Here......We study the alignment of the vacuum in gauge theories with $N_f$ Dirac fermions transforming according to a complex representation of the gauge group. The alignment of the vacuum is produced by adding a small mass perturbation to the theory. We study in detail the $N_f=2,3$ and $4$ case. For $N...... it is shown that at the point where $N_f-1$ flavors are degenerate with positive mass $m>0$ and the mass of the $N_f$'th flavor becomes negative and equal to $-m$ CP breaks spontaneously....

  20. Visualizing electromagnetic vacuum by MRI

    CERN Document Server

    Chandrashekar, Chandrika S; Chandrashekar, S; Taylor, Erika A; Taylor, Deanne M


    Based upon Maxwell's equations, it has long been established that oscillating electromagnetic (EM) fields incident upon a metal surface decay exponentially inside the conductor, leading to a virtual EM vacuum at sufficient depths. Magnetic resonance imaging (MRI) utilizes radiofrequency (r.f.) EM fields to produce images. Here we present the first visualization of an EM vacuum inside a bulk metal strip by MRI, amongst several novel findings. We uncover unexpected MRI intensity patterns arising from two orthogonal pairs of faces of a metal strip, and derive formulae for their intensity ratios. Further, we furnish chemical shift imaging (CSI) results that discriminate different faces (surfaces) of a metal block according to their distinct nuclear magnetic resonance (NMR) chemical shifts, which holds much promise for monitoring surface chemical reactions noninvasively. Bulk metals are ubiquitous, and MRI is a premier noninvasive diagnostic tool. Combining the two, the emerging field of bulk metal MRI can be expe...

  1. Quantum vacuum and dark matter

    CERN Document Server

    Hajdukovic, Dragan Slavkov


    Recently, the gravitational polarization of the quantum vacuum was proposed as alternative to the dark matter paradigm. In the present paper we consider four benchmark measurements: the universality of the central surface density of galaxy dark matter haloes, the cored dark matter haloes in dwarf spheroidal galaxies, the non-existence of dark disks in spiral galaxies and distribution of dark matter after collision of clusters of galaxies (the Bullet cluster is a famous example). Only some of these phenomena (but not all of them) can (in principle) be explained by the dark matter and the theories of modified gravity. However, we argue that the framework of the gravitational polarization of the quantum vacuum allows the understanding of the totality of these phenomena.

  2. CFD simulation of gas and particles combustion in biomass furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Griselin, Nicolas


    In this thesis, gas and particle combustion in biomass furnaces is investigated numerically. The aim of this thesis is to use Computational Fluid Dynamics (CFD) technology as an effective computer based simulation tool to study and develop the combustion processes in biomass furnaces. A detailed model for the numerical simulation of biomass combustion in a furnace, including fixed-bed modeling, gas-phase calculation (species distribution, temperature field, flow field) and gas-solid two-phase interaction for flying burning particles is presented. This model is used to understand the mechanisms of combustion and pollutant emissions under different conditions in small scale and large scale furnaces. The code used in the computations was developed at the Division of Fluid Mechanics, LTH. The flow field in the combustion enclosure is calculated by solving the Favre-averaged Navier-Stokes equations, with standard {kappa} - {epsilon} turbulence closure, together with the energy conservation equation and species transport equations. Discrete transfer method is used for calculating the radiation source term in the energy conservation equation. Finite difference is used to solve the general form of the equation yielding solutions for gas-phase temperatures, velocities, turbulence intensities and species concentrations. The code has been extended through this work in order to include two-phase flow simulation of particles and gas combustion. The Favre-averaged gas equations are solved in a Eulerian framework while the submodels for particle motion and combustion are used in the framework of a Lagrangian approach. Numerical simulations and measurement data of unburned hydrocarbons (UHC), CO, H{sub 2}, O{sub 2} and temperature on the top of the fixed bed are used to model the amount of tar and char formed during pyrolysis and combustion of biomass fuel in the bed. Different operating conditions are examined. Numerical calculations are compared with the measured data. It is

  3. Mass dependence of vacuum energy


    Fulling, S. A.


    The regularized vacuum energy (or energy density) of a quantum field subjected to static external conditions is shown to satisfy a certain partial differential equation with respect to two variables, the mass and the "time" (ultraviolet cutoff parameter). The equation is solved to provide integral expressions for the regularized energy (more precisely, the cylinder kernel) at positive mass in terms of that for zero mass. Alternatively, for fixed positive mass all coefficients in the short-tim...

  4. Vacuum configuration for inflationary superstring

    Energy Technology Data Exchange (ETDEWEB)

    Baadhio, R.A. (Theoretical Physics Group, Physics Division, Lawrence Berkeley Laboratory and Department of Physics, University of California at Berkeley, Berkeley, California 94720 (United States))


    The vacuum configuration for the inflationary superstring theory is established. It is argued that the basic physical contents of the inflationary universe are characterized by the Novikov higher signature. Finally it is shown, with respect to the splitting of Paper II, that the index of the Dirac operator defined in our inflated universe, and in the parallel shadow one, is indeed [ital h]-cobordant.

  5. Entanglement in the Bogoliubov vacuum

    DEFF Research Database (Denmark)

    Poulsen, Uffe Vestergaard; Meyer, T.; Lewenstein, M.


    We analyze the entanglement properties of the Bogoliubov vacuum, which is obtained as a second-order approximation to the ground state of an interacting Bose-Einstein condensate. We work in one- and two-dimensional lattices and study the entanglement between two groups of sites as a function...... and to be favoured by strong interactions. Conversely, long-range entanglement is favoured by relatively weak interactions. No examples of bound entanglement are found....

  6. Field Emission in Vacuum Microelectronics

    CERN Document Server

    Fursey, George; Schwoebel, Paul


    Field emission is a phenomenon described by quantum mechanics. Its emission capability is millions times higher than that of any other known types of electron emission. Nowadays this phenomenon is experiencing a new life due to wonderful applications in the atomic resolution microscopy, in electronic holography, and in the vacuum micro- and nanoelectronics in general. The main field emission properties, and some most remarkable experimental facts and applications, are described in this book.

  7. Oscillations of a polarizable vacuum

    Directory of Open Access Journals (Sweden)

    James G. Gilson


    Full Text Available A classical basis for one-dimensional Schrödinger quantum theory is constructed from simple vacuum polarization harmonic oscillators within standard stochastic theory. The model is constructed on a two-dimensional phase configuration surface with phase velocity vectors that have a speed of light zitterbewegung behaviour character. The system supplies a natural Hermitian scalar product describing probability density which is derived from angular momentum considerations. The generality of the model which is extensive is discussed.

  8. Feasibility study of utilizing solar furnace technology in steel making industry

    Energy Technology Data Exchange (ETDEWEB)

    Abbaspoursani, K. [The Faculty of Mechanical Engineering, Takestan Islamic Azad University (Iran, Islamic Republic of)], Email:; Tofigh, A.A.; Nahang Toudeshki, S.; Hadadian, A. [Department of Energy, Materials and Energy Research Center (Iran, Islamic Republic of)], Email:, email:, email:; Farahmandpour, B. [Iranian Fuel Conservation company (Iran, Islamic Republic of)], Email:


    In Iran, the casting industry consumes 33.6% of electricity production, and most of this electricity is used in the melting process. Currently, scrap preheating is done using electric arc furnaces and the aim of this study is to assess the feasibility of replacing electric arc furnaces with solar furnaces. The performance of solar furnaces in the Iran Alloy Steel Company under Yazd climate conditions was studied. It was found that the solar irradiation time and solar insulation are sufficient to operate a solar furnace with the capacity to preheat 250 thousand tons per year of scrap to 500 degrees celsius. Results showed that such a furnace would decrease energy consumption by 40 GWh per year and that it would take 5 years to return the investment. This study demonstrated that operating a solar furnace in the Iran Alloy Steel Company under Yazd climate conditions is feasible and would result in economic and environmental benefits.

  9. Microgravity Superagglomerates Produced By Silane And Acetylene (United States)

    Gokoglu, Suleyman (Technical Monitor); Bundy, Matthew; Mulholland, George W.; Manzello, Samuel; Yang, Jiann; Scott, John Henry; Sivathanu, Yudaya


    observed in microgravity butane jet diffusion flames by Ito et al.[2]. Several other works to date have studied the effect of flame structure on soot volume fraction and agglomeration size in a microgravity environment.[3-4]. In microgravity the absence of buoyant convective flows increases the residence time in the flame and causes a broadening of the high temperature region in the flame. Both of these factors play a significant role in gas phase radiation and soot formation

  10. Experiments Developed to Study Microgravity Smoldering Combustion (United States)

    Vergilii, Franklin


    The overall objective of the Microgravity Smoldering Combustion (MSC) research program is to understand and predict smoldering combustion under normal and microgravity (near-zero-gravity) conditions to help prevent and control smolder-originated fires, in both environments. Smoldering is defined as a nonflaming, self-sustaining, propagating, exothermic surface reaction. If a material is sufficiently permeable, smoldering is not confined to its outer surface, but can propagate as a reaction wave through the interior of the material. The MSC program will accomplish its goals by conducting smolder experiments on the ground and in a space-based laboratory, and developing theoretical models of the process. Space-based experiments are necessary because smoldering is a very slow process and, consequently, its study in a microgravity environment requires extended periods of time that can only be achieved in space. Smoldering can occur in a variety of processes ranging from the smolder of porous insulating materials to underground coal combustion. Many materials can sustain smoldering, including wood, cloth, foams, tobacco, other dry organic materials, and charcoal. The ignition, propagation, transition to flaming, and extinction of the smolder reaction are controlled by complex, thermochemical mechanisms that are not well understood. As with many forms of combustion, gravity affects the availability of the oxidizer and the transport of heat, and therefore, the rate of combustion. The smoldering combustion of porous materials has been studied both experimentally and theoretically, usually in the context of fire safety. Smoldering encompasses a number of fundamental processes, including heat and mass transfer in a porous media; endothermic pyrolysis of combustible material; ignition, propagation, and extinction of heterogeneous exothermic reactions at the solid-gas pore interface; and the onset of gas phase reactions (flaming) from existing surface reactions. Smoldering

  11. Running Jobs in the Vacuum (United States)

    McNab, A.; Stagni, F.; Ubeda Garcia, M.


    We present a model for the operation of computing nodes at a site using Virtual Machines (VMs), in which VMs are created and contextualized for experiments by the site itself. For the experiment, these VMs appear to be produced spontaneously "in the vacuum" rather having to ask the site to create each one. This model takes advantage of the existing pilot job frameworks adopted by many experiments. In the Vacuum model, the contextualization process starts a job agent within the VM and real jobs are fetched from the central task queue as normal. An implementation of the Vacuum scheme, Vac, is presented in which a VM factory runs on each physical worker node to create and contextualize its set of VMs. With this system, each node's VM factory can decide which experiments' VMs to run, based on site-wide target shares and on a peer-to-peer protocol in which the site's VM factories query each other to discover which VM types they are running. A property of this system is that there is no gate keeper service, head node, or batch system accepting and then directing jobs to particular worker nodes, avoiding several central points of failure. Finally, we describe tests of the Vac system using jobs from the central LHCb task queue, using the same contextualization procedure for VMs developed by LHCb for Clouds.

  12. Vacuum electronics applications at CERN

    CERN Document Server

    Jensen, E


    CERN operates a large number of vacuum electronics based RF power amplifiers covering a wide frequency range – over 300 sockets with 24 different grid tubes and klystrons are in use and require constant care to insure reliable operation of the accelerators. This is in particular true for the LHC and its injector chain, for which a program of improvement and stepwise upgrade has started. These include IOT’s for the SPS and klystrons and modulators for Linac4 and SPL. The CLIC study and the CTF3 facility are relevant to vacuum electronics in many ways: The CLIC primary RF power, to be provided at 1 GHz, requires highest possible efficiency and phase stability, MBK’s are likely candidates. The CLIC RF power source and CTF3 are themselves large vacuum electronics applications, consequently there are areas of common interest and concern, including fabrication techniques, pulse compression techniques, breakdown and multipactor theory and simulation, material fatigue, numerical analysis of slow-wave structures...

  13. Improved Aerogel Vacuum Thermal Insulation (United States)

    Ruemmele, Warren P.; Bue, Grant C.


    An improved design concept for aerogel vacuum thermal-insulation panels calls for multiple layers of aerogel sandwiched between layers of aluminized Mylar (or equivalent) poly(ethylene terephthalate), as depicted in the figure. This concept is applicable to both the rigid (brick) form and the flexible (blanket) form of aerogel vacuum thermal-insulation panels. Heretofore, the fabrication of a typical aerogel vacuum insulating panel has involved encapsulation of a single layer of aerogel in poly(ethylene terephthalate) and pumping of gases out of the aerogel-filled volume. A multilayer panel according to the improved design concept is fabricated in basically the same way: Multiple alternating layers of aerogel and aluminized poly(ethylene terephthalate) are assembled, then encapsulated in an outer layer of poly(ethylene terephthalate), and then the volume containing the multilayer structure is evacuated as in the single-layer case. The multilayer concept makes it possible to reduce effective thermal conductivity of a panel below that of a comparable single-layer panel, without adding weight or incurring other performance penalties. Implementation of the multilayer concept is simple and relatively inexpensive, involving only a few additional fabrication steps to assemble the multiple layers prior to evacuation. For a panel of the blanket type, the multilayer concept, affords the additional advantage of reduced stiffness.

  14. Recycling MgO-C refractory in electric arc furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Conejo, A.N. [Metallurgy Department, Morelia Technological Institute, Morelia (Mexico); Lule, R.G.; Lopez, F. [Process Engineering Department-Steelmaking Shop, Lazaro Cardenas City (Mexico); Rodriguez, R. [Refractories Department, Lazaro Cardenas City (Mexico)


    MgO-C refractory recycling from electric arc furnaces and ladle furnaces has been carried out during the melting of direct reduced iron (DRI). Metallurgical trials to define the effects of refractory recycling on energy consumption, melting time, flux consumption and refractory consumption are reported in this work. The method of preparation as well as the method of injection is also included in this study. Based on current results, the practice of recycling spent refractory is highly recommended. Visual inspection indicates the potential benefits in slag foaming which starts to form at the beginning of the heat thus allowing the use of full power transformer and in turn results in faster melting rates. (author)

  15. Fuzzy Logic Temperature Control System For The Induction Furnace

    Directory of Open Access Journals (Sweden)

    Lei Lei Hnin


    Full Text Available This research paper describes the fuzzy logic temperature control system of the induction furnace. Temperature requirement of the heating system varies during the heating process. In the conventional control schemes the switching losses increase with the change in the load. A closed loop control is required to have a smooth control on the system. In this system pulse width modulation based power control scheme for the induction heating system is developed using the fuzzy logic controller. The induction furnace requires a good voltage regulation to have efficient response. The controller controls the temperature depending upon weight of meat water and time. This control system is implemented in hardware system using microcontroller. Here the fuzzy logic controller is designed and simulated in MATLAB to get the desire condition.

  16. Orgin of Slag from Early Medieval Age Furnaces in Nitra

    Directory of Open Access Journals (Sweden)

    Julius Dekan


    Full Text Available Two types of archaeological artefacts from remains of Early Medieval Age furnaces excavated in Nitra are analysed. They are supposed to originate from slag of glass and iron production. Employing Mossbauer spectrometry, iron crystallographic sites are identified and compared. In all samples, Fe2+ and Fe3+ structural positions were revealed. Some of the archeological artefacts including those that were supposed to originate from glass production show a presence of metallic iron and/or magnetic oxides. Based on the results of Mossbauer effect measurements performed at room temperature as well as 77 K (liquid nitrogen temperature analytical evidence is provided that the iron sites identified are not as those usually encountered in glasses. Consequently, a conclusion is proposed that neither of the investigated furnaces was used for glass production.

  17. Annealing furnace for III-V semiconductor devices (United States)

    O'Connor, J. M.; Hier, H. S.; Ketchum, R. M.


    A furnace for annealing ion implantation damage in III-V semiconductors has been built and tested. Designed for research applications, the furnace can accommodate odd shapes of material up to 2 in. in diameter. Samples are loaded onto a novel cantilevered support and are not moved during the annealing operation, facilitating proximity annealing techniques. Both chambers of this dual chambered system are O-ring sealed for added safety during annealing in an arsine gas ambient. Electron mobilities between 4400 and 4600 cm2/V s at 300 K are routinely measured for 2×1017 cm-3 gallium arsenide material annealed in this sytem. The system has been used to anneal indium phosphide as well as gallium arsenide wafers.

  18. Advanced wood burning furnaces. 2. rev. ed.; Moderne Holzfeuerungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, W. (comp.)


    New and environment-friendly technologies meet high requirements in terms of emission reduction and comfort of operation. In the field of wood burning furnaces, there is still a lack of knowledge which results in excessive cost, environmental pollution and loss of image. This brochure shows how wood furnaces should be operated correctly and also reviews the state of the art. [German] Durch die technische Entwicklung neuer, wirkungsvoller und vor allem umweltfreundlicher Heiztechniken wird zudem den in den letzten Jahren gestiegenen Anforderungen an den Emissionsschutz und den Bedienungskomfort Rechnung getragen. Mit Holz wird jedoch z. T. nicht immer richtig geheizt. Das kostet Geld und fuehrt zu vermeidbaren Umweltbelastungen und Imageschaeden. Ziel dieser Broschuere ist es daher, mit den Techniken des Heizens mit Holz vertraut zu machen und einen Ueberblick ueber den heutigen Stand zu geben. (orig.)


    Directory of Open Access Journals (Sweden)

    Jan Mikula


    Full Text Available Mathematical modeling of heat aggregates is one of the fundamental methods of the mathematical modelling research. A mathematical model based on the method of elementary balances was created for the thermal treatment of granular and lumpy materials. The adaptation of the selected aggregate model is based on prior knowledge and experiments. The paper presents an adaptation of the mathematical model for the magnesite processing rotary furnace using the mode of caustic and clinker production. A simulation of the charge preheater impact based on the thin layer principle is implemented into the model. The main advantages of using this type of preheater of rotary furnace are smaller dimensions for a large exchange surface and low pressure losses.

  20. Thermal Spray Coatings for Blast Furnace Tuyere Application (United States)

    Pathak, A.; Sivakumar, G.; Prusty, D.; Shalini, J.; Dutta, M.; Joshi, S. V.


    The components in an integrated steel plant are invariably exposed to harsh working environments involving exposure to high temperatures, corrosive gases, and erosion/wear conditions. One such critical component in the blast furnace is the tuyere, which is prone to thermal damage by splashing of molten metal/slag, erosive damage by falling burden material, and corrosion from the ensuing gases. All the above, collectively or independently, accelerate tuyere failure, which presents a potential explosion hazard in a blast furnace. Recently, thermal spray coatings have emerged as an effective solution to mitigate such severe operational challenges. In the present work, five different coatings deposited using detonation spray and air plasma spray techniques were comprehensively characterized. Performance evaluation involving thermal cycling, hot corrosion, and erosion tests was also carried out. Based on the studies, a coating system was suggested for possible tuyere applications and found to yield substantial improvement in service life during actual field trials.

  1. Aerodynamic levitation : an approach to microgravity.

    Energy Technology Data Exchange (ETDEWEB)

    Glorieux, B.; Saboungi, M.-L.; Millot, F.; Enderby, J.; Rifflet, J.-C.


    Measurements of the thermophysical and structural properties of liquid materials at high temperature have undergone considerable development in the past few years. Following improvements in electromagnetic levitation, aerodynamic levitation associated with laser heating has shown promise for assessing properties of different molten materials (metals, oxides, and semiconductors), preserving sample purity over a wide range of temperatures and under different gas environments. The density, surface tension and viscosity are measured with a high-speed video camera and an image analysis system. Results on nickel and alumina show that small droplets can be considered in the first approximation to be under microgravity conditions. Using a non-invasive contactless technique recently developed to measure electrical conductivity, results have been extended to variety of materials ranging from liquid metals and liquid semiconductors to ionically conducting materials. The advantage of this technique is the feasibility of monitoring changes in transport occurring during phase transitions and in deeply undercooled states.

  2. Effect of Microgravity on Afferent Innervation (United States)


    Presentations and publications are: (1) an audiovisual summary web presentation on results from SLM-MIR avian experiments. A color presentation summarizing results from the SLM-MIR and STS-29 avian experiments; (2) color threshold and ratio of S 100B MAP5, NF68/200, GABA and GAD; (3) chicken (Gallus domesticus) inner ear afferents; (4) microgravity in the STS-29 Space Shuttle Discovery affected the vestibular system of chick embryos; (5) expression of S 100B in sensory and secretory cells of the vertebrate inner ear; (6) otoconia biogenesis, phylogeny, composition and functional attributes;(7) the glycan keratin sulfate in inner ear crystals; (8) elliptical-P cells in the avian perilymphatic interface of the tegmentum vasculosum; and (9) LAMP2c and S100B upregulation in brain stem after VIIIth nerve deafferentation.

  3. Vestibulospinal reflexes as a function of microgravity (United States)

    Reschke, M. F.; Homick, J. L.; Anderson, D. J.


    Data from previous manned space flights suggest that an exposure to microgravity produces significant alterations in vestibular, neuromuscular, and related sensory system functions. It is possible that the observed changes are a function of adaptation induced by altered otolith input. An experiment in Spacelab 1 was conducted with the aim to study this adaptation as it occurred in flight and after flight, and to relate the observed changes to mechanisms underlying space motion sickness. The concept was explored by making use of the anatomic pathway which links the otolith organs and spinal motoneurons. The overall sensitivity of the spinal motoneurons was tested by two related methods. One method involves the electrical excitation of neural tissue and the recording of vestibulospinal reflexes in conjunction with a brief linear acceleration. The second method is concerned with measurements of dynamic postural ataxia. Results suggest that more than a single time constant may be involved in man's ability to return to baseline values.

  4. High temperature furnace for nuclear magnetic resonance experiments

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, C.; Scheler, G. (Friedrich-Schiller-Universitaet, Jena (German Democratic Republic). Sektion Physik)


    A furnace is described for NMR experiments in the temperature range 300 to 1,100 K. It can be used both in a superconducting solenoid (Oxford Instruments, B/sub 0/ = 6.4 T, bore 52 mm) and in iron magnets with a gap d >= 48 mm. All for NMR experiments important nuclei can be measured without /sup 29/Si. The NMR probe can be used both for instationary and stationary experiments.

  5. Soil Stabilisation Using Ground Granulated Blast Furnace Slag


    Ashish Kumar Pathak; Dr. V. Pandey


    Stabilisation is a broad sense for the various methods employed and modifying the properties of a soil to improve its engineering performance and used for a variety of engineering works. In today‟s day soil stabilisation is the major problem for civil engineers, either for construction of road and also for increasing the strength or stability of soil and reduces the construction cost. In this thesis the soil are stabilised by ground granulated blast furnace slag (GGBS) and this material is ob...

  6. Characterization of calcium carbonate sorbent particle in furnace environment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Soo [Aerosol and Particle Technology Laboratory, Department of Mechanical Engineering, KAIST 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of); Jung, Jae Hee [Environment Sensor System Research Center, KIST 39-1 Hawolgok-dong, Seongbuk-gu, Seoul, 136-791 (Korea, Republic of); Keel, Sang In; Yun, Jin Han; Min, Tai Jin [Environmental Systems Research Division, KIMM 104 Sinseongno, Yuseong-gu, Daejeon, 305-343 (Korea, Republic of); Kim, Sang Soo, E-mail: [Aerosol and Particle Technology Laboratory, Department of Mechanical Engineering, KAIST 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of)


    The oxy-fuel combustion system is a promising technology to control CO{sub 2} and NO{sub X} emissions. Furthermore, sulfation reaction mechanism under CO{sub 2}-rich atmospheric condition in a furnace may lead to in-furnace desulfurization. In the present study, we evaluated characteristics of calcium carbonate (CaCO{sub 3}) sorbent particles under different atmospheric conditions. To examine the physical/chemical characteristics of CaCO{sub 3}, which is used as a sorbent particle for in-furnace desulfurization in the oxy-fuel combustion system, they were injected into high temperature drop tube furnace (DTF). Experiments were conducted at varying temperatures, residence times, and atmospheric conditions in a reactor. To evaluate the aerosolizing characteristics of the CaCO{sub 3} sorbent particle, changes in the size distribution and total particle concentration between the DTF inlet and outlet were measured. Structural changes (e.g., porosity, grain size, and morphology) of the calcined sorbent particles were estimated by BET/BJH, XRD, and SEM analyses. It was shown that sorbent particles rapidly calcined and sintered in the air atmosphere, whereas calcination was delayed in the CO{sub 2} atmosphere due to the higher CO{sub 2} partial pressure. Instead, the sintering effect was dominant in the CO{sub 2} atmosphere early in the reaction. Based on the SEM images, it was shown that the reactions of sorbent particles could be explained as a grain-subgrain structure model in both the air and CO{sub 2} atmospheres.

  7. Silica crown refractory corrosion in glass melting furnaces


    Balandis A.; Nizeviciene D.


    The critical parameters of silica refractories, such as compressive strength, bulk, density, quantity of silica, microstructure and porosity were evaluated of unused and used bricks to line the crowns of glass furnaces, when the rate of corrosion of crowns were about 2 times greater. The change of these parameters, the chemical composition and formation of the microcracks in the used silica refractories material were studied. It was established that the short time at service of containe...

  8. Demonstration and testing of high performance slot furnace. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bjerklie, J.W.; LaHaye, P.G.


    A demonstration and test program was conducted on a high temperature, 108'' slot, forge furnace. The efficacy of slot closures, medium weight insulation, massive-recirculation burners, temperature and O/sub 2/ controls, and ceramic recuperators was determined and compared to an unimproved furnace. Fired with No. 2 fuel oil at a maximum rate of 35 gph at start-up, the furnace was loaded manually employing 2/sup 1///sub 2/'' dia by 24'' long, round stock to simulate a typical forge shop load. Under these conditions, the furnace, with all improvements operative, achieved a steady state specific heat consumption (SHC) value of 850 Btu/lb of steel processed at an operating set point of 2400/sup 0/F and a steel processing rate of 3000 lbs/h. The value of each energy conserving improvement individually was determined and demonstrated. The largest single improvement was due to the ceramic recuperator (38%), followed by the door closures (11%), the massive-recirculation burners (10 to 20%), and improved wall thermal insulation (4%). The controls with the burner allowed essentially smoke-free operation to excess air levels of less than 5%. The economic impact of incorporating the energy-conserving recommendations of this study, using the industry ''norms'' for a conventionally equipped forge shop, was determined. Referred to the financial ''operating statement'', the improvement realized in the before-tax income of the forge shop would be increased approximately 20% assuming a current level of 10% profit before taxes.

  9. Blast furnace coke substitutes from Victorian brown coal


    Mollah, Mamun


    Iron is usually produced from its ores using coke in a blast furnace (BF). Coke, a hard and macroporous carbon material, is produced from special coals (coking coals) and acts as fuel, smelting agent, and the permeable support for the charge to the BF. No material can completely replace coke in a BF. Coking coals are becoming harder (and more expensive) to obtain. Victorian brown coal (VBC) is accessible, cheap, with low mineral concentrations, which is favourable for iron production in a BF....

  10. Detailed model for practical pulverized coal furnaces and gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Smith, P.J.; Smoot, L.D.


    This study has been supported by a consortium of nine industrial and governmental sponsors. Work was initiated on May 1, 1985 and completed August 31, 1989. The central objective of this work was to develop, evaluate and apply a practical combustion model for utility boilers, industrial furnaces and gasifiers. Key accomplishments have included: Development of an advanced first-generation, computer model for combustion in three dimensional furnaces; development of a new first generation fouling and slagging submodel; detailed evaluation of an existing NO{sub x} submodel; development and evaluation of an improved radiation submodel; preparation and distribution of a three-volume final report: (a) Volume 1: General Technical Report; (b) Volume 2: PCGC-3 User's Manual; (c) Volume 3: Data Book for Evaluation of Three-Dimensional Combustion Models; and organization of a user's workshop on the three-dimensional code. The furnace computer model developed under this study requires further development before it can be applied generally to all applications; however, it can be used now by specialists for many specific applications, including non-combusting systems and combusting geseous systems. A new combustion center was organized and work was initiated to continue the important research effort initiated by this study. 212 refs., 72 figs., 38 tabs.

  11. Silica crown refractory corrosion in glass melting furnaces

    Directory of Open Access Journals (Sweden)

    Balandis A.


    Full Text Available The critical parameters of silica refractories, such as compressive strength, bulk, density, quantity of silica, microstructure and porosity were evaluated of unused and used bricks to line the crowns of glass furnaces, when the rate of corrosion of crowns were about 2 times greater. The change of these parameters, the chemical composition and formation of the microcracks in the used silica refractories material were studied. It was established that the short time at service of container glass furnace crown can be related to low quality of silica brick: high quantity of CaO and impurities, low quantity of silica, low quantity of silica, transferred to tridymite and cristobalite and formation of 5-10 μm and more than 100 μm cracks in the crown material. The main reason of corrosion high quality silica bricks used to line the crown of electrovacuum glass furnace is the multiple cyclic change of crown temperature at 1405 - 1430°C range in the initial zone of crown and at 1575 - 1605°C range in the zone of highest temperatures.

  12. Methods of steel manufacturing - The electric arc furnace (United States)

    Dragna, E. C.; Ioana, A.; Constantin, N.


    Initially, the carbon content was reduced by mixing “the iron” with metallic ingots in ceramic crucibles/melting pots, with external heat input. As time went by the puddling procedure was developed, a procedure which also assumes a mixture with oxidized iron ore. In 1856 Bessemer invented the convertor, thus demonstrating that steel can be obtained following the transition of an air stream through the liquid pig iron. The invention of Thomas, a slightly modified basic-lined converter, fostered the desulphurization of the steel and the removal of the phosphate from it. During the same period, in 1865, in Sireuil, the Frenchman Martin applies Siemens’ heat regeneration invention and brings into service the furnace with a charge composed of iron pig, scrap iron and iron ore, that produces a high quality steel [1]. An act worthy of being highlighted within the scope of steelmaking is the start-up of the converter with oxygen injection at the upper side, as there are converters that can produce 400 tons of steel in approximately 50 minutes. Currently, the share of the steel produced in electric arc furnaces with a charge composed of scrap iron has increased. Due to this aspect, the electric arc furnace was able to impose itself on the market.


    Directory of Open Access Journals (Sweden)

    Felipe Fardin Grillo


    Full Text Available This research aims to study the process of incorporation of the mass in final hot metal and volatilization mass contained in the electric arc furnace dust (EAFD, by addition in hot metal at a temperature of 1,400°C; 1,450°C and 1,500°C altering experimental conditions such as the percentage of EAFD to be added and the percentage of silicon in hot metal. Previously, the EAFD was characterized using techniques of chemical analysis and size analysis. After characterization, the EAFD to be added to the hot metal was agglomerated in the form of briquettes. The achievement of fusion experiments in laboratory scale was placed in a vertical tubular furnace with temperature control. A flow of inert gas (argon was maintained inside the furnace during the experiments. The result of the sample EAFD volatilized shows that there is an increase in the zinc concentration when compared with the concentration of zinc present in EAFD “as received”.


    Directory of Open Access Journals (Sweden)

    Nelson Felipe Llovet de Armas


    Full Text Available A refinery furnace used for heating crude oil showed abundant pelicules with unusual thicknesses in some pipes located in the convection zone, next to the wall of the furnace. The purpose of this research consisted in identifying the type of corrosion and determine the causes that originated the formation of the unusual pelicules. With the objective of elucidating which technological factors propitiated this deterioration, a visual inspection of the furnace was carried out to evaluate its structural state. From the values reported as thermocouples, temperature profiles of operation in the convection zone were obtained. The pelicules obtained were characterized using the X-ray diffraction technique and a metallographic microscope of reflected light. The results showed several deposits among the convection tubes; which cannot be eliminated because there isn't an adequate system of removal. This problem is accentuated by the substitution of old refractory bricks by modern monolithic panels. Such situation favored the formation of canalizations or preferential zones that propitiated the increase of the velocity of gases to high temperature and a rise of the concentration of O2 on low alloy steel pipes. These factors caused an anomalous behavior of the temperatures of operation and the formation of pelicules of mill scale type, of macrocrystalline structures, constituted for few adherent iron oxides and unusual thicknesses. These results show a severe oxidation in high temperatures.

  15. Effects of microgravity environment on intracellular signal transduction pathways

    Directory of Open Access Journals (Sweden)

    De CHANG


    Full Text Available Microgravity environment is a stress and extracellular signal that affects cellular morphology and function through signal transduction system, thus leading to certain biological effect. At present, many signaling pathways have been reported to be involved in the regulation of cell function under microgravity environment, such as NF-κB signaling pathway, Notch signaling pathway, MAPK signaling pathway, HSP signaling pathway and so on, and these reports have laid a foundation for the molecular studies of cytolergy under outer space environment. The recent progress in the researches on intracellular signaling pathways affected by microgravity is herewith reviewed in present paper in the hope of providing references for understanding the cell activity in space environment, and to find the ways to alleviate the harmful effects caused by the microgravity environment.

  16. The science capability of the Low Temperature Microgravity Physics Facility (United States)

    Larson, M.; Croonquist, A.; Dick, G. J.; Liu, Y.


    The Low Temperature Microgravity Physics Facility (LTMPF) is a multiple user and multiple-flight NASA facility that will provide a low temperature environment for about 4. 5 months on board the International Space Station (ISS).

  17. Testing Numerical Modeling of Phase Coarsening by Microgravity Experiments (United States)

    Wang, K. G.; Glicksman, M. E.


    Quantitative understanding of the morphological evolution that occurs during phase coarsening is crucial for optimization of processing procedures to control the final structure and properties of multiphase materials. Generally, ground-based experimental studies of phase coarsening in solids are limited to model alloy systems. Data from microgravity experiments on phase coarsening in Sn-Pb solid-liquid mixtures, executed on the International Space Station, are archived in NASA's Physical Sciences Informatics (PSI) system. In such microgravity experiments, it is expected that the rate of sedimentation will be greatly reduced compared with terrestrial conditions, allowing the kinetics of phase coarsening to be followed more carefully and accurately. In this work we tested existing numerical models of phase coarsening using NASA's PSI microgravity data. Specially, we compared the microstructures derived from phase-field and multiparticle diffusion simulations with those observed in microgravity experiments.

  18. The potential impact of microgravity science and technology on education (United States)

    Wargo, M. J.


    The development of educational support materials by NASA's Microgravity Science and Applications Division is discussed in the light of two programs. Descriptions of the inception and application possibilities are given for the Microgravity-Science Teacher's Guide and the program of Undergraduate Research Opportunities in Microgravity Science and Technology. The guide is intended to introduce students to the principles and research efforts related to microgravity, and the undergraduate program is intended to reinforce interest in the space program. The use of computers and electronic communications is shown to be an important catalyst for the educational efforts. It is suggested that student and teacher access to these programs be enhanced so that they can have a broader impact on the educational development of space-related knowledge.

  19. The Influence of Microgravity on Invasive Growth in Saccharomyces cerevisiae (United States)

    Van Mulders, Sebastiaan E.; Stassen, Catherine; Daenen, Luk; Devreese, Bart; Siewers, Verena; van Eijsden, Rudy G. E.; Nielsen, Jens; Delvaux, Freddy R.; Willaert, Ronnie


    This study investigates the effects of microgravity on colony growth and the morphological transition from single cells to short invasive filaments in the model eukaryotic organism Saccharomyces cerevisiae. Two-dimensional spreading of the yeast colonies grown on semi-solid agar medium was reduced under microgravity in the Σ1278b laboratory strain but not in the CMBSESA1 industrial strain. This was supported by the Σ1278b proteome map under microgravity conditions, which revealed upregulation of proteins linked to anaerobic conditions. The Σ1278b strain showed a reduced invasive growth in the center of the yeast colony. Bud scar distribution was slightly affected, with a switch toward more random budding. Together, microgravity conditions disturb spatially programmed budding patterns and generate strain-dependent growth differences in yeast colonies on semi-solid medium.

  20. A hydroponic design for microgravity and gravity installations (United States)

    Fielder, Judith; Leggett, Nickolaus


    A hydroponic system is presented that is designed for use in microgravity or gravity experiments. The system uses a sponge-like growing medium installed in tubular modules. The modules contain the plant roots and manage the flow of the nutrient solution. The physical design and materials considerations are discussed, as are modifications of the basic design for use in microgravity or gravity experiments. The major external environmental requirements are also presented.

  1. Effect of microgravity on forearm subcutaneous vascular resistance in humans

    DEFF Research Database (Denmark)

    Gabrielsen, A; Norsk, P; Videbæk, R


    To test the hypothesis that the subcutaneous vascular constrictor response to an orthostatic stress in humans is augmented after exposure to microgravity, the following experiment was performed. Four male astronauts underwent a standardized stepwise lower body negative pressure (LBNP) profile 5 m...... after 1-2 days after exposure to 10 days of microgravity and could act as a defense mechanism to alleviate decreased orthostatic tolerance...

  2. Comparison of possibilities the blast furnace and cupola slag utilization by concrete production

    Directory of Open Access Journals (Sweden)

    D. Baricová


    Full Text Available In process of pig iron and cast iron production secondary raw materials and industrial wastes are formed The most abundant secondaryproduct originating in these processes are furnace slag. Blast furnace slag and cupola furnace slag originates from melting of gangue parts of metal bearing materials, slag forming additions and coke ash. In general, slag are compounds of oxides of metallic and non-metallic elements, which form chemical compounds and solutions with each other and also contain small volume of metals, sulfides of metals and gases. Chemical, mineralogical and physical properties of slag determinate their utilisation in different fields of industry.The paper presents results from the research of the blast furnace and cupola furnace slag utilization in the concrete production. Pilotexperiments of the concrete production were performed, by that the blast furnace and cupola furnace slag with a fractions of 0–4mm;4–8mm; 8–16mm were used as a natural substitute. A cupola furnace slag and combination of the blast furnace and cupola furnace slagwere used in the experiments. The analysis results show that such concretes are suitable for less demanding applications.

  3. Proteomic Analysis of Rat Hippocampus under Simulated Microgravity (United States)

    Wang, Yun; Li, Yujuan; Zhang, Yongqian; Liu, Yahui; Deng, Yulin

    It has been found that microgravity may lead to impairments in cognitive functions performed by CNS. However, the exact mechanism of effects of microgravity on the learning and memory function in animal nervous system is not elucidated yet. Brain function is mainly mediated by membrane proteins and their dysfunction causes degeneration of the learning and memory. To induce simulated microgravity, the rat tail suspension model was established. Comparative O (18) labeling quantitative proteomic strategy was applied to detect the differentially expressed proteins in rat brain hippocampus. The proteins in membrane fraction from rat hippocampus were digested by trypsin and then the peptides were separated by off-gel for the first dimension with 24 wells device encompassing the pH range of 3 - 10. An off-gel fraction was subjected into LC-ESI-QTOF in triplicate. Preliminary results showed that nearly 77% of the peptides identified were specific to one fraction. 676 proteins were identified among which 108 proteins were found differentially expressed under simulated microgravity. Using the KOBAS server, many enriched pathways, such as metabolic pathway, synaptic vesicle cycle, endocytosis, calcium signaling pathway, and SNAREs pathway were identified. Furthermore, it has been found that neurotransmitter released by Ca (2+) -triggered synaptic vesicles fusion may play key role in neural function. Rab 3A might inhibit the membrane fusion and neurotransmitter release. The protein alteration of the synaptic vesicle cycle may further explain the effects of microgravity on learning and memory function in rats. Key words: Microgravity; proteomics; synaptic vesicle; O (18) ({}) -labeling

  4. Vacuum Chambers for LEP sections

    CERN Multimedia


    The picture shows sections of the LEP vacuum chambers to be installed in the dipole magnets (left) and in the quadrupoles (right). The dipole chamber has three channels: the beam chamber, the pumping duct where the NEG (non-evaporabe getter) is installed and the water channel for cooling (on top in the picture). The pumping duct is connected to the beam chamber through holes in the separating wall. The thick lead lining to shield radiation can also be seen. These chambers were manufactured as extruded aluminium alloy profiles.

  5. Thin-wall vacuum domain evolution

    Directory of Open Access Journals (Sweden)

    V.A. Berezin


    Full Text Available In the framework of general relativity the equation of motion of a thin-wall vacuum shell is derived at arbitrary values of the vacuum parameters inside and outside the shell. We obtain that the velocity of the walls of the true vacuum bubble at its expansion does not tend to the velocity of light. We find that vacuum shells could exist now in the universe, which do not contradict to observational cosmology. The types of black holes created are investigated. Restrictions on the mass of the black holes formed from remnants of the false vacuum and on the fraction of the vacuum energy pumped into such black holes are obtained.

  6. A new vacuum for Loop Quantum Gravity

    CERN Document Server

    Dittrich, Bianca


    We construct a new vacuum for loop quantum gravity, which is dual to the Ashtekar-Lewandowski vacuum. Because it is based on BF theory, this new vacuum is physical for $(2+1)$-dimensional gravity, and much closer to the spirit of spin foam quantization in general. To construct this new vacuum and the associated representation of quantum observables, we introduce a modified holonomy-flux algebra which is cylindrically consistent with respect to the notion of refinement by time evolution suggested in [1]. This supports the proposal for a construction of a physical vacuum made in [1,2], also for $(3+1)$-dimensional gravity. We expect that the vacuum introduced here will facilitate the extraction of large scale physics and cosmological predictions from loop quantum gravity.

  7. Vacuum systems for the ILC helical undulator

    CERN Document Server

    Malyshev, O B; Clarke, J A; Bailey, I R; Dainton, J B; Malysheva, L I; Barber, D P; Cooke, P; Baynham, E; Bradshaw, T; Brummitt, A; Carr, S; Ivanyushenkov, Y; Rochford, J; Moortgat-Pick, G A


    The International Linear Collider (ILC) positron source uses a helical undulator to generate polarized photons of ∼10MeV∼10MeV at the first harmonic. Unlike many undulators used in synchrotron radiation sources, the ILC helical undulator vacuum chamber will be bombarded by photons, generated by the undulator, with energies mostly below that of the first harmonic. Achieving the vacuum specification of ∼100nTorr∼100nTorr in a narrow chamber of 4–6mm4–6mm inner diameter, with a long length of 100–200m100–200m, makes the design of the vacuum system challenging. This article describes the vacuum specifications and calculations of the flux and energy of photons irradiating the undulator vacuum chamber and considers possible vacuum system design solutions for two cases: cryogenic and room temperature.

  8. Sensorimotor adaptations to microgravity in humans (United States)

    Edgerton, V. R.; McCall, G. E.; Hodgson, J. A.; Gotto, J.; Goulet, C.; Fleischmann, K.; Roy, R. R.


    Motor function is altered by microgravity, but little detail is available as to what these changes are and how changes in the individual components of the sensorimotor system affect the control of movement. Further, there is little information on whether the changes in motor performance reflect immediate or chronic adaptations to changing gravitational environments. To determine the effects of microgravity on the neural control properties of selected motor pools, four male astronauts from the NASA STS-78 mission performed motor tasks requiring the maintenance of either ankle dorsiflexor or plantarflexor torque. Torques of 10 or 50% of a maximal voluntary contraction (MVC) were requested of the subjects during 10 degrees peak-to-peak sinusoidal movements at 0.5 Hz. When 10% MVC of the plantarflexors was requested, the actual torques generated in-flight were similar to pre-flight values. Post-flight torques were higher than pre- and in-flight torques. The actual torques when 50% MVC was requested were higher in- and post-flight than pre-flight. Soleus (Sol) electromyographic (EMG) amplitudes during plantarflexion were higher in-flight than pre- or post-flight for both the 10 and 50% MVC tasks. No differences in medial gastrocnemius (MG) EMG amplitudes were observed for either the 10 or 50% MVC tasks. The EMG amplitudes of the tibialis anterior (TA), an antagonist to plantarflexion, were higher in- and post-flight than pre-flight for the 50% MVC task. During the dorsiflexion tasks, the torques generated in both the 10 and 50% MVC tasks did not differ pre-, in- and post-flight. TA EMG amplitudes were significantly higher in- than pre-flight for both the 10 or 50% MVC tasks, and remained elevated post-flight for the 50% MVC test. Both the Sol and MG EMG amplitudes were significantly higher in-flight than either pre- or post-flight for both the 10 and 50% MVC tests. These data suggest that the most consistent response to space flight was an elevation in the level of

  9. Straw detector: 1 - Vacuum: 0

    CERN Multimedia

    Katarina Anthony


    The NA62 straw tracker is using pioneering CERN technology to measure charged particles from very rare kaon decays. For the first time, a large straw tracker with a 4.4 m2 coverage will be placed directly into an experiment’s vacuum tank, allowing physicists to measure the direction and momentum of charged particles with extreme precision. NA62 measurements using this technique will help physicists take a clear look at the kaon decay rate, which might be influenced by particles and processes that are not included in the Standard Model.   Straw ends are glued to an aluminium frame, a crucial step in the assembly of a module. The ends are then visually inspected before a leak test is performed.  “Although straw detectors have been around since the 1980s, what makes the NA62 straw trackers different is that they can work under vacuum,” explains Hans Danielsson from the PH-DT group leading the NA62 straw project. Straw detectors are basically small drift cha...

  10. Gases vacuum dedusting and cooling

    Directory of Open Access Journals (Sweden)

    Alexey А. Burov


    Full Text Available Represented are the results of operating the ladle degassing vacuum plant (productivity: 120 tons of liquid steel with various dust collectors. The process gases’ cooling and dedusting, obtained in the closed loop buran study, provides opportunity to install a bag filter after that closed loop and its efficient use. Proven is the effectiveness of the cylindrical cyclone replacement with a multichannel (buran dust collector, based on a system of closed-loop (return coupling serially connected curved ducts, where the dusty gas flow rotation axis is vertically positioned. The system of closed-loop serially connected curvilinear channels creates preconditions for the emergence of a negative feedback at the curvilinear gas flow containing transit and circulating flows. These conditions are embodied with circulating flows connecting the in- and outputs of the whole system each channel. The transit flow multiple continuous filtration through the circulating dust layers leads to the formation and accumulation of particles aggregates in the collection chamber. The validity of such a dusty flow control mechanism is confirmed by experimental data obtained in a vacuum chamber. Therefore, replacing one of the two buran’s forevacuum pumps assemblies with the necessary number of curved channels (closed loop is estimated in a promising method.

  11. Vacuum silicon photomultipliers: Recent developments

    Energy Technology Data Exchange (ETDEWEB)

    Barbarino, Giancarlo [Dipartimento Scienze Fisiche, Università “Federico II” Napoli (Italy); INFN Napoli (Italy); Barbato, Felicia Carla Tiziana [INFN Napoli (Italy); Campajola, Luigi [Dipartimento Scienze Fisiche, Università “Federico II” Napoli (Italy); Asmundis, Riccardo de [INFN Napoli (Italy); De Rosa, Gianfranca [Dipartimento Scienze Fisiche, Università “Federico II” Napoli (Italy); Mollo, Carlos Maximiliano [INFN Napoli (Italy); Vivolo, Daniele, E-mail: [Dipartimento Scienze Fisiche, Università “Federico II” Napoli (Italy); INFN Napoli (Italy)


    VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an innovative design for a modern hybrid, high gain, silicon based photodetector based on the combination of a SiPM with a hemispherical vacuum glass PMT standard envelope. In such a device photoelectrons emitted by the photocathode are accelerated and focused by an electric field towards a small focal area covered by the SiPM which therefore acts as an amplifier, thus substituting the classical dynode chain of a PMT. With a view to the realization of a first prototype of VSiPMT our group is carrying out a preliminary work aimed at the study of SiPM performances as an electron detector, including an accurate Geant4-based simulation of the interaction between SiPM and electron beams. In order to perform a full characterization of the SiPM we developed an experimental setup for the extraction and the acceleration of a beam of backward secondary electrons emitted after the bombardment of a carbon foil by a proton beam extracted in a TTT-3 accelerator.

  12. Vacuum Attachment for XRF Scanner (United States)

    Schramm, Harry F.; Kaiser, Bruce


    Vacuum apparatuses have been developed for increasing the range of elements that can be identified by use of x-ray fluorescent (XRF) scanners of the type mentioned in the two immediately preceding articles. As a consequence of the underlying physical principles, in the presence of air, such an XRF scanner is limited to analysis of chlorine and elements of greater atomic number. When the XRF scanner is operated in a vacuum, it extends the range of analysis to lower atomic numbers - even as far as aluminum and sodium. Hence, more elements will be available for use in XRF labeling of objects as discussed in the two preceding articles. The added benefits of the extended capabilities also have other uses for NASA. Detection of elements of low atomic number is of high interest to the aerospace community. High-strength aluminum alloys will be easily analyzed for composition. Silicon, a major contaminant in certain processes, will be detectable before the process is begun, possibly eliminating weld or adhesion problems. Exotic alloys will be evaluated for composition prior to being placed in service where lives depend on them. And in the less glamorous applications, such as bolts and fasteners, substandard products and counterfeit items will be evaluated at the receiving function and never allowed to enter the operation

  13. Free and membrane-bound calcium in microgravity and microgravity effects at the membrane level (United States)

    Belyavskaya, N. A.

    The changes of [Ca^2+]_i controlled is known to play a key regulatory role in numerous cellular processes especially associated with membranes. Previous studies from our laboratory have demonstrated an increase in calcium level in root cells of pea seedlings grown aboard orbital station ``Salyut 6'' /1/. These results: 1) indicate that observed Ca^2+-binding sites of membranes also consist in proteins and phospholipids; 2) suggest that such effects of space flight in membrane Ca-binding might be due to the enhancement of Ca^2+ influx through membranes. In model presented, I propose that Ca^2+-activated channels in plasma membrane in response to microgravity allow the movement of Ca^2+ into the root cells, causing a rise in cytoplasmic free Ca^2+ levels. The latter, in its turn, may induce the inhibition of a Ca^2+ efflux by Ca^2+-activated ATPases and through a Ca^2+/H^+ antiport. It is possible that increased cytosolic levels of Ca^2+ ions have stimulated hydrolysis and turnover of phosphatidylinositols, with a consequent elevation of cytosolic [Ca^2+]_i. Plant cell can response to such a Ca^2+ rise by an enhancement of membranous Ca^2+-binding activities to rescue thus a cell from an abundance of a cytotoxin. A Ca^2+-induced phase separation of membranous lipids assists to appear the structure nonstable zones with high energy level at the boundary of microdomains which are rich by some phospholipid components; there is mixing of molecules of the membranes contacted in these zones, the first stage of membranous fusion, which was found in plants exposed to microgravity. These results support the hypothesis that a target for microgravity effect is the flux mechanism of Ca^2+ to plant cell.


    Directory of Open Access Journals (Sweden)

    S.. V. Korneev


    Full Text Available The paper presents an analysis of specific features of lining thermal performance in electric-arc furnaces at various technological periods. It has been  shown that on the basis of mathematical modeling methods for thermal processes it is possible to predict power consumption of furnaces at the operational split schedule with due account of such furnace characteristics as capacity, lining materials, furnace idle times under closed and open conditions etc. The paper shows distinctions in thermal performance of acid and the basic linings in the electric-arc furnaces. The proposed approach allows to analyze thermal losses by heat conductivity and on accumulation by a refractory lining and rather accurately to determine the required balance sheet items while calculating power consumption during various periods of scrap melting for furnaces of various capacity.

  15. Experimental Investigation of Flow Condensation in Microgravity (United States)

    Lee, Hyoungsoon; Park, Ilchung; Konishi, Christopher; Mudawar, Issam; May, Rochelle I.; Juergens, Jeffery R.; Wagner, James D.; Hall, Nancy R.; Nahra, Henry K.; Hasan, Mohammed M.; hide


    Future manned missions to Mars are expected to greatly increase the space vehicle's size, weight, and heat dissipation requirements. An effective means to reducing both size and weight is to replace single-phase thermal management systems with two-phase counterparts that capitalize upon both latent and sensible heat of the coolant rather than sensible heat alone. This shift is expected to yield orders of magnitude enhancements in flow boiling and condensation heat transfer coefficients. A major challenge to this shift is a lack of reliable tools for accurate prediction of two-phase pressure drop and heat transfer coefficient in reduced gravity. Developing such tools will require a sophisticated experimental facility to enable investigators to perform both flow boiling and condensation experiments in microgravity in pursuit of reliable databases. This study will discuss the development of the Flow Boiling and Condensation Experiment (FBCE) for the International Space Station (ISS), which was initiated in 2012 in collaboration between Purdue University and NASA Glenn Research Center. This facility was recently tested in parabolic flight to acquire condensation data for FC-72 in microgravity, aided by high-speed video analysis of interfacial structure of the condensation film. The condensation is achieved by rejecting heat to a counter flow of water, and experiments were performed at different mass velocities of FC-72 and water and different FC-72 inlet qualities. It is shown that the film flow varies from smooth-laminar to wavy-laminar and ultimately turbulent with increasing FC-72 mass velocity. The heat transfer coefficient is highest near the inlet of the condensation tube, where the film is thinnest, and decreases monotonically along the tube, except for high FC-72 mass velocities, where the heat transfer coefficient is enhanced downstream. This enhancement is attributed to both turbulence and increased interfacial waviness. One-ge correlations are shown to

  16. Cold vacuum drying facility design requirements

    Energy Technology Data Exchange (ETDEWEB)

    IRWIN, J.J.


    This document provides the detailed design requirements for the Spent Nuclear Fuel Project Cold Vacuum Drying Facility. Process, safety, and quality assurance requirements and interfaces are specified.

  17. Vacuum Compatible Percussive Dynamic Cone Penetrometer Project (United States)

    National Aeronautics and Space Administration — Honeybee Robotics proposes to develop a vacuum compatible percussive dynamic cone penetrometer (PDCP), for establishing soil bin characteristics, with the ultimate...

  18. Vacuum Technology Considerations For Mass Metrology (United States)

    Abbott, Patrick J.; Jabour, Zeina J.


    Vacuum weighing of mass artifacts eliminates the necessity of air buoyancy correction and its contribution to the measurement uncertainty. Vacuum weighing is also an important process in the experiments currently underway for the redefinition of the SI mass unit, the kilogram. Creating the optimum vacuum environment for mass metrology requires careful design and selection of construction materials, plumbing components, pumping, and pressure gauging technologies. We review the vacuum technology1 required for mass metrology and suggest procedures and hardware for successful and reproducible operation. PMID:26989593

  19. Quantum vacuum noise in physics and cosmology. (United States)

    Davies, P. C. W.


    The concept of the vacuum in quantum field theory is a subtle one. Vacuum states have a rich and complex set of properties that produce distinctive, though usually exceedingly small, physical effects. Quantum vacuum noise is familiar in optical and electronic devices, but in this paper I wish to consider extending the discussion to systems in which gravitation, or large accelerations, are important. This leads to the prediction of vacuum friction: The quantum vacuum can act in a manner reminiscent of a viscous fluid. One result is that rapidly changing gravitational fields can create particles from the vacuum, and in turn the backreaction on the gravitational dynamics operates like a damping force. I consider such effects in early universe cosmology and the theory of quantum black holes, including the possibility that the large-scale structure of the universe might be produced by quantum vacuum noise in an early inflationary phase. I also discuss the curious phenomenon that an observer who accelerates through a quantum vacuum perceives a bath of thermal radiation closely analogous to Hawking radiation from black holes, even though an inertial observer registers no particles. The effects predicted raise very deep and unresolved issues about the nature of quantum particles, the role of the observer, and the relationship between the quantum vacuum and the concepts of information and entropy. (c) 2001 American Institute of Physics.

  20. Vacuum technology in the chemical industry

    CERN Document Server

    Jorisch, Wolfgang


    Based on the very successful German edition and a seminar held by the German Engineers` Association (VDI) on a regular basis for years now, this English edition has been thoroughly updated and revised to reflect the latest developments. It supplies in particular the special aspects of vacuum technology, applied vacuum pump types and vacuum engineering in the chemical, pharmaceutical and process industry application-segments. The text includes chapters dedicated to latest European regulations for operating in hazardous zones with vacuum systems, methods for process pressure control and regulati

  1. Blast furnace coke properties and the influence on off-gas dust


    Lundgren, Maria


    In blast furnace ironmaking, efforts are made to decrease the coke consumption mainly by increasing the pulverized coal injection rate. This will cause changes in in-furnace reduction conditions, burden distribution and demands on raw material strength, etc. In order to maintain stable operation and minimize material losses through the off-gas, it is important to understand fines generation and behaviour in the blast furnace.  The strength and reactivity of coke at high temperature, measured ...

  2. Precision control of high temperature furnaces using an auxiliary power supply and charged practice current flow (United States)

    Pollock, George G.


    Two power supplies are combined to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved.

  3. Precision control of high temperature furnaces using an auxiliary power supply and charged particle current flow (United States)

    Pollock, G.G.


    Two power supplies are combined to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved. 5 figs.

  4. Optimized Choice for Pollution Control Systems in Smelting Furnaces with Green Approach


    Parviz Jafari-Fesharaki; Elham Ghazanchaei; Beheshteh Jebelli


     Furnace division is one of the most polluted divisions ever known in the steel industry associated with several environmental pollutions. This study attempted to choose optimally, a pollution control system for dust emission from steel furnaces with the Green and environmentally friendly approach. Three electric smelting furnaces with 3, 6 and 12-ton output capacity were selected. The level of energy cost and consumption, capital and environmental damage, and indexes of environmental sustain...

  5. Thermal Oxidation of Tail Gases from the Production of Oil-furnace Carbon Black


    Bosak, Z.; Barta, D.; Zečević, N.; S. Šiklušić


    This paper describes the production technology of oil-furnace carbon black, as well as the selected solution for preventing the emissions of this process from contaminating the environment.The products of industrial oil-furnace carbon black production are different grades of carbon black and process tail gases. The qualitative composition of these tail gases during the production of oil-furnace carbon black are: carbon(IV) oxide, carbon(II) oxide, hydrogen, methane, hydrogen sulfide, nitrogen...

  6. Development of charge calculation program for target steel in induction furnace


    Saliu O. SEIDU; Adetunji ONIGBAJUMO


    This paper presents the development of charge calculation program for target steel in induction furnace. The simulation modelling function developed is based on mass balance analysis of the furnace production. The process engineering of the furnace follows linear algebraic mathematical function. Visual basic programming language (C#) is used in the coding and interface integration. This is used to develop a unit process based simulation program with user friendly interface f...

  7. How to Make a Microgravity Drop Tower for Your Classroom (United States)

    DeLombard, Richard; Hall, Nancy R.


    Microgravity is quite often seen as exotic and special as astronauts float around in the International Space Station, eating MM's in mid-air, and performing science experiments, all done seemingly without gravity being present. Surprisingly enough, up on the ISS there is about 90 of the same gravity that holds you to the floor in your classroom or museum exhibit hall. Participate in this session and you will understand that and more. You can use simple devices to demonstrate microgravity conditions in your classroom or museum exhibit hall. This will be the same microgravity condition that astronauts experience on the ISS, just for a much shorter period of time. Contrary to popular opinion of some people, microgravity is NOT caused by zero gravity up there. Microgravity on the ISS is due to free fall within the Earth's gravitational field. That means you can drop an item in free fall in your classroom and museum exhibit hall and that item will experience microgravity. In this session, a short theory segment will explain and reinforce these concepts so that you may explain to others. The session will concentrate on showing the session participants how to make an effective, but inexpensive, drop tower for use in the classroom. Such a drop tower may be used to reinforce classroom instruction in physics and forces motion as well as serve as a platform for student investigations, classroom competitions, and student science or technology fair entries. Session participants will build their own simple microgravity experiment and operate them in a drop tower, compare results, and modify their experiment based on results. This material is also useful for public demonstrations at school open houses, travelling museum exhibits, fixed museum exhibits, and independent student projects or experiments. These free fall concepts also connect terrestrial demonstrations with planetary moon motion, comet trajectory, and more.

  8. Hydrodynamics in a circulating fluidized bed with annular furnace and six parallel cyclones (United States)

    Shuai, Daping; Wang, Xiaofang; Lyu, Qinggang


    Systematic measurements were conducted on a cold CFB with annular furnace and six parallel cyclones to study gas-solids flow in the annular furnace and flow non-uniformity among six cyclones. The results show that axial solids holdup in the annular furnace decreases exponentially with height, similar to the conventional rectangular furnace. The uniform transverse distribution of solids holdup suggests a good gas-solids mixing in the annular furnace. The annular furnace presents the core/double-annulus flow structure, and it results in enhanced gas-solids back-mixing than the conventional core/annulus flow structure. The gas-solids flow of the inner wall-layer and the outer wall-layer is very close at most part of the furnace height, and the wall-layer thickness decreases with height. Flow non-uniformity exists among six parallel cyclones in the annular furnace CFB. But non-uniform distribution of solids circulating rates and cyclone pressure drops show no regularity, and the flow non-uniformity is no larger than the CFBs with conventional furnace. Under typical operating conditions, the relative deviation of six solids circulating rates is 8.0%.

  9. Modeling energy consumption of residential furnaces and boilers in U.S. homes

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, James; Dunham-Whitehead, Camilla; Lekov, Alex; McMahon, James


    In 2001, DOE initiated a rulemaking process to consider whether to amend the existing energy efficiency standards for furnaces and boilers. A key factor in DOE's consideration of new standards is their cost-effectiveness to consumers. Determining cost-effectiveness requires an appropriate comparison of the additional first cost of energy efficiency design options with the savings in operating costs. This report describes calculation of equipment energy consumption (fuel and electricity) based on estimated conditions in a sample of homes that are representative of expected furnace and boiler installations. To represent actual houses with furnaces and boilers in the United States, we used a set of houses from the Residential Energy Consumption Survey of 1997 conducted by the Energy Information Administration. Our calculation methodology estimates the energy consumption of alternative (more-efficient) furnaces, if they were to be used in each house in place of the existing equipment. We developed the method of calculation described in this report for non-weatherized gas furnaces. We generalized the energy consumption calculation for this product class to the other furnace product classes. Fuel consumption calculations for boilers are similar to those for the other furnace product classes. The electricity calculations for boilers are simpler than for furnaces, because boilers do not provide thermal distribution for space cooling as furnaces often do.

  10. Acid slag injection into the blast furnace tuyere zone

    Energy Technology Data Exchange (ETDEWEB)

    Haerkki, J.; Tervola, K. [Oulu Univ. (Finland). Dept. of Process Engineering


    The possibility of acid slag injection and its effect on the slag formation and on the melting behaviour of the charge materials are studied in the present work. The work is partly based on the literature evaluating the slag formation, slag properties and the basic slag injection. The possibility of acid slag injection is first examined by studying changes in the composition of the primary slag if the share of the acid slag component (Kostamus pellet/RR) of the charge material is lowered. Phase diagrams and viscosity charts are used to evaluate the viscosity, and solidus/liquidus temperature in the slag phase. The share of the slag phase of the pellet is evaluated by calculating the amount of the acid slag injection. The injection rate of some injectants is also examined. The primary slag formed of the sinter and the coke ash is in liquid form and its viscosity is close to the viscosity of the blast furnace slag. It is possible that the liquid slag phase can be formed in the blast furnace without the presence of the acid pellet because the melting point and the viscosity of the slag is lowered by alkalies, sulfur and the dissolved ironoxide of the slag. If high SiO{sub 2} content materials alone are used for injection there is a risk that the slag phase of the tuyere zone becomes too viscous. Olivine and some iron containing components such as fayalite are possible injection material. More information is needed to evaluate the effect of acid slag injection on the operation of the blast furnace. (orig.) SULA 2 Research Programme; 2 refs.

  11. A hydroponic system for microgravity plant experiments (United States)

    Wright, B. D.; Bausch, W. C.; Knott, W. M.


    The construction of a permanently manned space station will provide the opportunity to grow plants for weeks or months in orbit for experiments or food production. With this opportunity comes the need for a method to provide plants with a continuous supply of water and nutrients in microgravity. The Capillary Effect Root Environment System (CERES) uses capillary forces to maintain control of circulating plant nutrient solution in the weightless environment of an orbiting spacecraft. The nutrient solution is maintained at a pressure slightly less than the ambient air pressure while it flows on one side of a porous membrane. The root, on the other side of the membrane, is surrounded by a thin film of nutrient solution where it contacts the moist surface of the membrane. The root is provided with water, nutrients and air simultaneously. Air bubbles in the nutrient solution are removed using a hydrophobic/hydrophilic membrane system. A model scaled to the size necessary for flight hardware to test CERES in the space shuttle was constructed.

  12. Overview of NASA's Microgravity Materials Science Program (United States)

    Downey, James Patton


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

  13. Mechanobiologic Research in a Microgravity Environment Bioreactor (United States)

    Guidi, A.; Dubini, G.; Tominetti, F.; Raimondi, M.

    mechanical forces. For example, cartilage constructs have been cultured in spinner flasks under mixed or unmixed conditions, in simulated and in real microgravity. In these mixing studies, however, it is difficult to definitively quantify the effects of mixing-induced mechanical forces from those of convection-enhanced transport of nutrients to and of catabolites away from the cells. At the state of the art, the presence of a more controlled mechanical environment may be the condition required in order to study the biochemical and mechanical response of these biological systems. Such a controlled environment could lead to an advanced fluid dynamic design of the culture chamber that could both enhance the local mass transfer phenomena and match the needs of specific macroscopic mechanical effects in tissue development. The bioreactor is an excellent example of how the skills and resources of two distinctly different fields can complement each other. Microgravity can be used to enhance the formation of tissue like aggregates in specially designed bioreactors. Theoretical and experimental projects are under way to improve cell culture techniques using microgravity conditions experienced during space flights. Bioreactors usable under space flight conditions impose constructional principles which are different from those intended solely for ground applications. The Columbus Laboratory as part of the International Space Station (ISS) will be an evolving facility in low Earth orbit. Its mission is to support scientific, technological, and commercial activities in space. A goal of this research is to design a unique bioreactor for use sequentially from ground research to space research. One of the particularities of the simulated microgravity obtained through time averaging of the weight vector is that by varying the rotational velocity the same results can be obtained with a different value of g. One of the first applications of this technique in space biology was in fact the

  14. Early development of fern gametophytes in microgravity (United States)

    Roux, Stanley J.; Chatterjee, Ani; Hillier, Sheila; Cannon, Tom

    Dormant spores of the fern Ceratopteris richardii were flown on Shuttle mission STS-93 to evaluate the effects of /micro-g on their development and on their pattern of gene expression. Prior to flight the spores were sterilized and sown into one of two environments: (1) Microscope slides in a video-microscopy module; and (2) Petri dishes. All spores were then stored in darkness until use. Spore germination was initiated on orbit after exposure to light. For the spores on microscope slides, cell level changes were recorded through the clear spore coat of the spores by video microscopy. After their exposure to light, spores in petri dishes were frozen in orbit at four different time points during which on earth gravity fixes the polarity of their development. Spores were then stored frozen in Biological Research in Canister units until recovery on earth. The RNAs from these cells and from /1-g control cells were extracted and analyzed on earth after flight to assay changes in gene expression. Video microscopy results revealed that the germinated spores developed normally in microgravity, although the polarity of their development, which is guided by gravity on earth, was random in space. Differential Display-PCR analyses of RNA extracted from space-flown cells showed that there was about a 5% change in the pattern of gene expression between cells developing in /micro-g compared to those developing on earth.

  15. Microgravity Transport Phenomena Experiment (MTPE) Overview (United States)

    Mason, Larry W.


    The Microgravity Transport Phenomena Experiment (MTPE) is a fluids experiment supported by the Fundamentals in Biotechnology program in association with the Human Exploration and Development of Space (BEDS) initiative. The MTP Experiment will investigate fluid transport phenomena both in ground based experiments and in the microgravity environment. Many fluid transport processes are affected by gravity. Osmotic flux kinetics in planar membrane systems have been shown to be influenced by gravimetric orientation, either through convective mixing caused by unstably stratified fluid layers, or through a stable fluid boundary layer structure that forms in association with the membrane. Coupled transport phenomena also show gravity related effects. Coefficients associated with coupled transport processes are defined in terms of a steady state condition. Buoyancy (gravity) driven convection interferes with the attainment of steady state, and the measurement of coupled processes. The MTP Experiment measures the kinetics of molecular migration that occurs in fluids, in response to the application of various driving potentials. Three separate driving potentials may be applied to the MTP Experiment fluids, either singly or in combination. The driving potentials include chemical potential, thermal potential, and electrical potential. Two separate fluid arrangements are used to study membrane mediated and bulk fluid transport phenomena. Transport processes of interest in membrane mediated systems include diffusion, osmosis, and streaming potential. Bulk fluid processes of interest include coupled phenomena such as the Soret Effect, Dufour Effect, Donnan Effect, and thermal diffusion potential. MTP Experiments are performed in the Microgravity Transport Apparatus (MTA), an instrument that has been developed specifically for precision measurement of transport processes. Experiment fluids are contained within the MTA fluid cells, designed to create a one dimensional flow geometry

  16. NASA's Microgravity Fluid Physics Strategic Research Roadmap (United States)

    Motil, Brian J.; Singh, Bhim S.


    The Microgravity Fluid Physics Program at NASA has developed a substantial investigator base engaging a broad crosssection of the U.S. scientific community. As a result, it enjoys a rich history of many significant scientific achievements. The research supported by the program has produced many important findings that have been published in prestigious journals such as Science, Nature, Journal of Fluid Mechanics, Physics of Fluids, and many others. The focus of the program so far has primarily been on fundamental scientific studies. However, a recent shift in emphasis at NASA to develop advanced technologies to enable future exploration of space has provided motivation to add a strategic research component to the program. This has set into motion a year of intense planning within NASA including three workshops to solicit inputs from the external scientific community. The planning activities and the workshops have resulted in a prioritized list of strategic research issues along with a corresponding detailed roadmap specific to fluid physics. The results of these activities were provided to NASA s Office of Biological and Physical Research (OBPR) to support the development of the Enterprise Strategy document. This paper summarizes these results while showing how the planned research supports NASA s overall vision through OBPR s organizing questions.

  17. The Microgravity Research Experiments (MICREX) Data Base (United States)

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


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

  18. Evolution of coke properties while descending through a blast furnace


    Hilding, Tobias


    Due to increasing price and economic pressures, there is a need to minimise coke consumption. The lesser amount of coke used has indirectly set higher standards for coke quality and led to a wish for even more knowledge about its function in the blast furnace. Over the last 20 years, coke quality has been strongly dictated by the so- called CSR value because it was believed that a higher CSR leads to improvement in productivity and more stable operation. Due to lack of suitable coals, often c...

  19. Improving the Quality of Electric Energy to Electric Arc Furnace

    Directory of Open Access Journals (Sweden)

    Adrian-Ioan Toma


    Full Text Available This paper presents a study of power quality problems created by an electric arc furnace (EAF with eccentric bottom tap (EBT at power system. The analysis have been done to EAF of 100 t capacity used for steel melting. Experimental results show this EAF is substantial source of electric disturbances, such as voltage fluctuations, flicker, harmonics, and unbalance between phases. Improvement of the quality of electric energy at EAF imposes a careful technical and economical analysis. Of all possible solutions for improvement of the power quality for an EAF (passive filter, STATCOM or SVC, SVC is the ideal solution.

  20. Investigation of Electric Arc Furnace Chemical Reactions and stirring effect


    Deng, Lei


    Chemical energy plays a big role in the process of modern Electric Arc Furnace (EAF). The objective of this study is to compare the results of chemical reaction enthalpies calculated by four different methods. In general, the “PERRY-NIST-JANAF method” is used to calculate the chemical energies. However, this method heavily depend on heat capacities of the substances which have to be deduced from  “Perry’s Chemical Engineers’ Handbook” and “NIST-JANAF Thermochemical Tables”, even the calculati...

  1. A study of slag freezing in metallurgical furnaces (United States)

    Guevara, Fernando

    Many smelting and slag-cleaning furnaces operate with cooling systems designed to freeze a slag layer over the refractory to protect it. The fluid flow and heat transfer conditions associated with the freeze layer and mushy zones are poorly understood. This study was conducted to understand the chill layer formation and heat transfer that is required to design cooling systems in pyrometallurgical operations where a slag layer is required to protect the furnace wall. The freeze layer formation and heat transfer in mushy zones were experimentally study at room temperature in a 2-dimensional square cavity differentially heated, using an aqueous solution of calcium chloride to simulate the slag. Reasonable similarity with conditions encountered with copper and nickel smelting systems was achieved (Pr ≈ 50 and Ra ≈ 108, in the laminar-turbulent transition). Measurements of velocities were made with the Particle Image Velocimetry (PIV) technique. The freeze layer development was tracked using a digital camera. Direct Numerical Simulations (DNS) of the mean flow using a finite control volume technique with a fixed domain method were also made of the unsteady fluid flow and heat transfer problem. It was found that the macro solidification process is well described using an improved model for high molecular viscosity in the mushy zone. Solid front growth, isothermal profiles, velocity profiles and heat transfer through the walls showed good agreement between the PIV and DNS results. Experimental and numerical velocity profiles close to the freeze layer show a parabolic behaviour in the vertical velocity profile which is completely different from the calculation of heat transfer using a sharp interface model. The reason for this is attributed to the effects of the mushy zone with a high viscosity and high shear stresses acting on that area. In Part III of this Thesis, effects of slag viscosity temperature relationship were analysed with a two-dimensional mathematical

  2. Physiology of a microgravity environment invited review: microgravity and skeletal muscle (United States)

    Fitts, R. H.; Riley, D. R.; Widrick, J. J.


    Spaceflight (SF) has been shown to cause skeletal muscle atrophy; a loss in force and power; and, in the first few weeks, a preferential atrophy of extensors over flexors. The atrophy primarily results from a reduced protein synthesis that is likely triggered by the removal of the antigravity load. Contractile proteins are lost out of proportion to other cellular proteins, and the actin thin filament is lost disproportionately to the myosin thick filament. The decline in contractile protein explains the decrease in force per cross-sectional area, whereas the thin-filament loss may explain the observed postflight increase in the maximal velocity of shortening in the type I and IIa fiber types. Importantly, the microgravity-induced decline in peak power is partially offset by the increased fiber velocity. Muscle velocity is further increased by the microgravity-induced expression of fast-type myosin isozymes in slow fibers (hybrid I/II fibers) and by the increased expression of fast type II fiber types. SF increases the susceptibility of skeletal muscle to damage, with the actual damage elicited during postflight reloading. Evidence in rats indicates that SF increases fatigability and reduces the capacity for fat oxidation in skeletal muscles. Future studies will be required to establish the cellular and molecular mechanisms of the SF-induced muscle atrophy and functional loss and to develop effective exercise countermeasures.

  3. Determination of Kicker Vacuum Requirements

    Energy Technology Data Exchange (ETDEWEB)

    Schulze, Martin E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    This note examines the effect of elevated vacuum pressures in the kicker region of the DARHT 2nd Axis which can lead to changes in the beam tune due to the long pulse length. The kicker uses Rexolite as an insulator supporting the electrodes. Rexolite is hygroscopic resulting is a large outgassing rate and prolonged pump down times after exposure to atmospheric conditions. LAMDA [1] is used to simulate the effect of ionization of the residual gas resulting in partial space charge neutralization and changes to the tune between the beginning and end of the pulse. The effect of the ion-hose instability is also examined. The purpose of this note is to establish/validate the required pressure in the downstream transport.

  4. TRIUMF cyclotron vacuum system refurbishing (United States)

    Sekachev, I.


    The cyclotron at TRIUMF was commissioned to full energy in 1974. The volume of the cyclotron vacuum tank is about 100 m3 and it operates at 5×10-8 Torr pressure during beam production. The pumping is mainly based on a Phillips B-20 cryogenerator (Stirling cycle 4-cylinder engine). The cryogenerator supplies helium gas at 16 K and 70 K to cryopanels in the tank. The decreasing reliability of the B-20 and demanding maintenance requirements triggered the decision to completely overhaul or replace the cryogenerator. Replacement with the LINDE-1630 helium refrigerator was found to be the most attractive (technically and economically) option. The details of the proposal with installation of the helium refrigerator and with a continuous flow liquid nitrogen shield cooling system are presented.

  5. Progress of ITER vacuum vessel

    Energy Technology Data Exchange (ETDEWEB)

    Ioki, K., E-mail: [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Bayon, A. [F4E, c/ Josep Pla, No. 2, Torres Diagonal Litoral, Edificio B3, E-08019 Barcelona (Spain); Choi, C.H.; Daly, E.; Dani, S.; Davis, J.; Giraud, B.; Gribov, Y.; Hamlyn-Harris, C.; Jun, C.; Levesy, B. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Kim, B.C. [NFRI, 52 Yeoeundong Yuseonggu, Daejeon 305-333 (Korea, Republic of); Kuzmin, E. [NTC “Sintez”, Efremov Inst., 189631 Metallostroy, St. Petersburg (Russian Federation); Le Barbier, R.; Martinez, J.-M. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Pathak, H. [ITER-India, A-29, GIDC Electronic Estate, Sector 25, Gandhinagar 382025 (India); Preble, J. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); Sa, J.W. [NFRI, 52 Yeoeundong Yuseonggu, Daejeon 305-333 (Korea, Republic of); Terasawa, A.; Utin, Yu. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-lez-Durance (France); and others


    Highlights: ► This covers the overall status and progress of the ITER vacuum vessel activities. ► It includes design, R and D, manufacturing and approval process of the regulators. ► The baseline design was completed and now manufacturing designs are on-going. ► R and D includes ISI, dynamic test of keys and lip-seal welding/cutting technology. ► The VV suppliers produced full-scale mock-ups and started VV manufacturing. -- Abstract: Design modifications were implemented in the vacuum vessel (VV) baseline design in 2011–2012 for finalization. The modifications are mostly due to interface components, such as support rails and feedthroughs for the in-vessel coils (IVC). Manufacturing designs are being developed at the domestic agencies (DAs) based on the baseline design. The VV support design was also finalized and tests on scale mock-ups are under preparation. Design of the in-wall shielding (IWS) has progressed, considering the assembly methods and the required tolerances. Further modifications are required to be consistent with the DAs’ manufacturing designs. Dynamic tests on the inter-modular and stub keys to support the blanket modules are being performed to measure the dynamic amplification factor (DAF). An in-service inspection (ISI) plan has been developed and R and D was launched for ISI. Conceptual design of the VV instrumentation has been developed. The VV baseline design was approved by the agreed notified body (ANB) in accordance with the French Nuclear Pressure Equipment Order procedure.

  6. Microgravity: A Teacher's Guide With Activities in Science, Mathematics, and Technology (United States)

    Rogers, Melissa J. B.; Vogt, Gregory L.; Wargo, Michael J.


    The purpose of this curriculum supplement guide is to define and explain microgravity and show how microgravity can help us learn about the phenomena of our world. The front section of the guide is designed to provide teachers of science, mathematics, and technology at many levels with a foundation in microgravity science and applications. It begins with background information for the teacher on what microgravity is and how it is created. This is followed with information on the domains of microgravity science research; biotechnology, combustion science, fluid physics, fundamental physics, materials science, and microgravity research geared toward exploration. The background section concludes with a history of microgravity research and the expectations microgravity scientists have for research on the International Space Station. Finally, the guide concludes with a suggested reading list, NASA educational resources including electronic resources, and an evaluation questionnaire.

  7. The Prospective Function of Curcumin Against the Negative Effects of Microgravity (United States)

    Lewis, A.; Johnson, P.; Jejelowo, O. A.; Sodipe, A.; Shishodia, S.


    Microgravity has several deleterious effects on cells. These cells may exhibit an up-regulation or down-regulation of their gene expression. We are investigating the effects of the phytochemical curcumin on microgravity-induced deleterious effects.

  8. Microgravity: Teacher's guide with activities for physical science (United States)

    Vogt, Gregory L.; Wargo, Michael J.; Rosenberg, Carla B. (Editor)


    This guide is an educational tool for teachers of grades 5 through 12. It is an introduction to microgravity and its application to spaceborne laboratory experiments. Specific payloads and missions are mentioned with limited detail, including Spacelab, the International Microgravity Laboratory, and the United States Microgravity Laboratory. Activities for students demonstrate chemistry, mathematics, and physics applications of microgravity. Activity objectives include: modeling how satellites orbit Earth; demonstrating that free fall eliminates the local effects of gravity; measuring the acceleration environments created by different motions; using a plasma sheet to observe acceleration forces that are experienced on board a space vehicle; demonstrating how mass can be measured in microgravity; feeling how inertia affects acceleration; observing the gravity-driven fluid flow that is caused by differences in solution density; studying surface tension and the fluid flows caused by differences in surface tension; illustrating the effects of gravity on the burning rate of candles; observing candle flame properties in free fall; measuring the contact angle of a fluid; illustrating the effects of gravity and surface tension on fiber pulling; observing crystal growth phenomena in a 1-g environment; investigating temperature effects on crystal growth; and observing crystal nucleation and growth rate during directional solidification. Each activity includes a background section, procedure, and follow-up questions.

  9. Confinement of light in a polarizable vacuum

    Directory of Open Access Journals (Sweden)

    Avinash Khare


    Full Text Available We show that an electrically polarizable vacuum with space-dependent permeability ε(r = μ−1(rexp(−αr2 can confine light whose quanta acquire a mass through interaction with this vacuum.

  10. Robot Vacuum Cleaner Personality and Behavior

    NARCIS (Netherlands)

    Hendriks, A.F.M.; Meerbeek, B.W.; Boess, S.; Pauws, S.C; Sonneveld, M.


    In this paper we report our study on the user experience of robot vacuum cleaner behavior. How do people want to experience this new type of cleaning appliance? Interviews were conducted to elicit a desired robot vacuum cleaner personality. With this knowledge in mind, behavior was designed for a

  11. Vacuum alignment with and without elementary scalars

    DEFF Research Database (Denmark)

    Alanne, Tommi; Gertov, Helene; Meroni, Aurora


    We systematically elucidate differences and similarities of the vacuum alignment issue in composite and renormalizable elementary extensions of the Standard Model featuring a pseudo-Goldstone Higgs. We also provide general conditions for the stability of the vacuum in the elementary framework...

  12. Vacuum sewerage system: an appropriate and economical ...

    African Journals Online (AJOL)

    However, vacuum technology has grown enormously in the last years. This paper reviews the applicability of the vacuum system as opposed to gravity systems, especially in Botswana. It is based on the training and visits to installed systems at Shoshong (Botswana), Dubai (UAE) and Hanau (Germany) offered by Roediger ...

  13. AA, vacuum tank for stochastic precooling

    CERN Document Server

    CERN PhotoLab


    The vaccum tank in which the fast stochastic precooling kicker was installed. It is clad with heating jackets for bake-out to 200 deg C, indispensable for reaching the operational vacuum of 7E-11 Torr. Alain Poncet, responsible for AA vacuum, is looking on. See also 7910268, 8002234.

  14. Silicates materials of high vacuum technology

    CERN Document Server

    Espe, Werner


    Materials of High Vacuum Technology, Volume 2: Silicates covers silicate insulators of special importance to vacuum technology. The book discusses the manufacture, composition, and physical and chemical properties of technical glasses, quartz glass, quartzware, vycor glass, ceramic materials, mica, and asbestos.

  15. Anaerobic polymers as high vacuum leak sealants (United States)

    Kendall, B. R. F.


    Anaerobic polymers are useful as solventless leak sealants with good vacuum properties at moderate temperatures. Loctite 290 can seal leaks in a range generally encountered in carefully constructed ultrahigh vacuum and high vacuum systems. It was found that small leaks are sealed best under vacuum, whereas large leaks should be sealed at atmospheric pressure. The high-temperature behavior of Loctite 290 is limited by its fast cure, which prevents deep penetration into small leaks; cracking eventually occurs at the entrance to the leak. Repeated thermal cycling to about 300 C is possible, however, provided viscosity, curing time, and leak size are properly matched to ensure penetration into the body of the leak. This may require special formulations for high temperature vacuum applications.

  16. Vacuum and ultravacuum physics and technology

    CERN Document Server

    Bello, Igor


    Vacuum technology has enormous impact on human life in many aspects and fields, such as metallurgy, material development and production, food and electronic industry, microelectronics, device fabrication, physics, materials science, space science, engineering, chemistry, technology of low temperature, pharmaceutical industry, and biology. All decorative coatings used in jewelries and various daily products—including shiny decorative papers, the surface finish of watches, and light fixtures—are made using vacuum technological processes. Vacuum analytical techniques and vacuum technologies are pillars of the technological processes, material synthesis, deposition, and material analyses—all of which are used in the development of novel materials, increasing the value of industrial products, controlling the technological processes, and ensuring the high product quality. Based on physical models and calculated examples, the book provides a deeper look inside the vacuum physics and technology.

  17. Photodesorption of gases in vacuum glazing (United States)

    Ng, N.; Collins, R. E.; So, L.


    When samples of vacuum glazing are exposed to sunlight, the pressure within these devices is observed to increase. The major gas species released have been identified using mass spectroscopic techniques, and are found to be carbon monoxide and carbon dioxide rather than water vapor as in thermally degraded vacuum glazing. Different measuring techniques, including the use of a spinning rotor gauge, were developed to study the time dependence of pressure in samples of vacuum glazing during sunlight exposure. The mechanism associated with optical stability of vacuum glazing has been studied. High temperature baking during the evacuation stage of the manufacturing process for vacuum glazing greatly improves the stability of these devices under optical illumination.

  18. Mechanics and Physics of Precise Vacuum Mechanisms

    CERN Document Server

    Deulin, E. A; Panfilov, Yu V; Nevshupa, R. A


    In this book the Russian expertise in the field of the design of precise vacuum mechanics is summarized. A wide range of physical applications of mechanism design in electronic, optical-electronic, chemical, and aerospace industries is presented in a comprehensible way. Topics treated include the method of microparticles flow regulation and its determination in vacuum equipment and mechanisms of electronics; precise mechanisms of nanoscale precision based on magnetic and electric rheology; precise harmonic rotary and not-coaxial nut-screw linear motion vacuum feedthroughs with technical parameters considered the best in the world; elastically deformed vacuum motion feedthroughs without friction couples usage; the computer system of vacuum mechanisms failure predicting. This English edition incorporates a number of features which should improve its usefulness as a textbook without changing the basic organization or the general philosophy of presentation of the subject matter of the original Russian work. Exper...

  19. Secondary metabolism in simulated microgravity: beta-lactam production by Streptomyces clavuligerus (United States)

    Fang, A.; Pierson, D. L.; Mishra, S. K.; Koenig, D. W.; Demain, A. L.


    Rotating bioreactors designed at NASA's Johnson Space Center were used to simulate a microgravity environment in which to study secondary metabolism. The system examined was beta-lactam antibiotic production by Streptomyces clavuligerus. Both growth and beta-lactam production occurred in simulated microgravity. Stimulatory effects of phosphate and L-lysine, previously detected in normal gravity, also occurred in simulated microgravity. The degree of beta-lactam antibiotic production was markedly inhibited by simulated microgravity.

  20. Ferromanganese Furnace Modelling Using Object-Oriented Principles

    Energy Technology Data Exchange (ETDEWEB)

    Wasboe, S.O.


    This doctoral thesis defines an object-oriented framework for aiding unit process modelling and applies it to model high-carbon ferromanganese furnaces. A framework is proposed for aiding modelling of the internal topology and the phenomena taking place inside unit processes. Complex unit processes may consist of a number of zones where different phenomena take place. A topology is therefore defined for the unit process itself, which shows the relations between the zones. Inside each zone there is a set of chemical species and phenomena, such as reactions, phase transitions, heat transfer etc. A formalized graphical methodology is developed as a tool for modelling these zones and their interaction. The symbols defined in the graphical framework are associated with objects and classes. The rules for linking the objects are described using OMT (Object Modeling Technique) diagrams and formal language formulations. The basic classes that are defined are implemented using the C++ programming language. The ferromanganese process is a complex unit process. A general description of the process equipment is given, and a detailed discussion of the process itself and a system theoretical overview of it. The object-oriented framework is then used to develop a dynamic model based on mass and energy balances. The model is validated by measurements from an industrial furnace. 101 refs., 119 figs., 20 tabs.

  1. Preparation of Ceramic-Bonded Carbon Block for Blast Furnace (United States)

    Li, Yiwei; Li, Yawei; Sang, Shaobai; Chen, Xilai; Zhao, Lei; Li, Yuanbing; Li, Shujing


    Traditional carbon blocks for blast furnaces are mainly produced with electrically calcined anthracite owing to its good hot metal corrosion resistance. However, this kind of material shows low thermal conductivity and does not meet the demands for cooling of the hearth and the bottom of blast furnaces. In this article, a new kind of a high-performance carbon block has been prepared via ceramic-bonded carbon (CBC) technology in a coke bed at 1673 K (1400 °C) using artificial graphite aggregate, alumina, metallic aluminum, and silicon powders as starting materials. The results showed that artificial graphite aggregates were strongly bonded by the three-dimensional network of ceramic phases in carbon blocks. In this case, the good resistance of the CBC blocks against erosion/corrosion by the hot metal is provided by the ceramic matrix and the high thermal conductivity by the graphite aggregates. The microstructure of this carbon block resembles that of CBC composites with a mean pore size of less than 0.1 μm, and up to 90 pct of the porosity shows a pore size <1 μm. Its thermal conductivity is higher than 30 W · m-1 · K-1 [293 K (20 °C)]. Meanwhile, its hot metal corrosion resistance is better than that of traditional carbon blocks.

  2. Self-calibrated active pyrometer for furnace temperature measurements (United States)

    Woskov, Paul P.; Cohn, Daniel R.; Titus, Charles H.; Surma, Jeffrey E.


    Pyrometer with a probe beam superimposed on its field-of-view for furnace temperature measurements. The pyrometer includes a heterodyne millimeter/sub-millimeter-wave or microwave receiver including a millimeter/sub-millimeter-wave or microwave source for probing. The receiver is adapted to receive radiation from a surface whose temperature is to be measured. The radiation includes a surface emission portion and a surface reflection portion which includes the probe beam energy reflected from the surface. The surface emission portion is related to the surface temperature and the surface reflection portion is related to the emissivity of the surface. The simultaneous measurement of surface emissivity serves as a real time calibration of the temperature measurement. In an alternative embodiment, a translatable base plate and a visible laser beam allow slow mapping out of interference patterns and obtaining peak values therefor. The invention also includes a waveguide having a replaceable end portion, an insulating refractory sleeve and/or a source of inert gas flow. The pyrometer may be used in conjunction with a waveguide to form a system for temperature measurements in a furnace. The system may employ a chopper or alternatively, be constructed without a chopper. The system may also include an auxiliary reflector for surface emissivity measurements.

  3. Characterization study of electric arc furnace dust phases

    Directory of Open Access Journals (Sweden)

    Janaína Gonçalves Maria da Silva Machado


    Full Text Available Electric arc furnace dust (EAFD is a solid waste generated in the collection of particulate material during steelmaking process in electric arc furnace. The aim of this work is to carry out a chemical and structural characterization of two EAFD samples with different Zn contents. Optical emission spectroscopy via inductively coupled plasma (ICP, X ray diffractometry (XRD and Mössbauer spectroscopy analysis were carried out in such EAFD samples. From XRD measurements, the samples exhibits the following phases: ZnFe2O4, Fe3O4, MgFe2O4, FeCr2O4, Ca0.15Fe2.85O4, MgO, Mn3O4, SiO2 and ZnO. The phases detected by Mössbauer spectroscopy were: ZnFe2O4, Fe3O4, Ca0.15Fe2.85O4 and FeCr2O4. Magnesium ferrite (MgFe2O4, observed in the XRD patterns as overlapped peaks, was not identified in the Mössbauer spectroscopy analysis.

  4. Optimization for blast furnace slag dry cooling granulation device (United States)

    Dazhan, Sheng; Yali, Wang; Ruiyun, Wang; Suping, Cui; Xiaoyu, Ma


    Since the large accumulation amount of blast furnace slag (BFS) with recycling value, it has become a hot topic for recovery utilization. Compared with the existing various BFS granulation process, the dry granulation process can promote the use of blast furnace granulated slag as cement substitute and concrete admixtures. Our research group developed a novel dry cooling granulation experiment device to treat BFS. However, there are still some problems to be solved. The purpose of this research is to improve the cooling and granulation efficiency of the existing dry type cooling equipment. This topic uses the FLUENT simulation software to study the impact of the number of air inlet on the cooling effect of the device. The simulation result is that the device possessing eight air inlets can increase the number of hot and cold gas exchanged, resulting in a better cooling effect. According to the power consumption, LCA analysis was carried out on the cooling granulation process. The results show that the device equipped eight air inlets not only improved the original equipment cooling granulation effect, but also increased resource utilization ratio, realized energy-saving and emission reduction.

  5. Microgravity Science Glovebox (MSG), Space Science's Past, Present and Future Aboard the International Space Station (ISS) (United States)

    Spivey, Reggie; Spearing, Scott; Jordan, Lee


    The Microgravity Science Glovebox (MSG) is a double rack facility aboard the International Space Station (ISS), which accommodates science and technology investigations in a "workbench' type environment. The MSG has been operating on the ISS since July 2002 and is currently located in the US Laboratory Module. In fact, the MSG has been used for over 10,000 hours of scientific payload operations and plans to continue for the life of ISS. The facility has an enclosed working volume that is held at a negative pressure with respect to the crew living area. This allows the facility to provide two levels of containment for small parts, particulates, fluids, and gases. This containment approach protects the crew from possible hazardous operations that take place inside the MSG work volume and allows researchers a controlled pristine environment for their needs. Research investigations operating inside the MSG are provided a large 255 liter enclosed work space, 1000 watts of dc power via a versatile supply interface (120, 28, + 12, and 5 Vdc), 1000 watts of cooling capability, video and data recording and real time downlink, ground commanding capabilities, access to ISS Vacuum Exhaust and Vacuum Resource Systems, and gaseous nitrogen supply. These capabilities make the MSG one of the most utilized facilities on ISS. MSG investigations have involved research in cryogenic fluid management, fluid physics, spacecraft fire safety, materials science, combustion, and plant growth technologies. Modifications to the MSG facility are currently under way to expand the capabilities and provide for investigations involving Life Science and Biological research. In addition, the MSG video system is being replaced with a state-of-the-art, digital video system with high definition/high speed capabilities, and with near real-time downlink capabilities. This paper will provide an overview of the MSG facility, a synopsis of the research that has already been accomplished in the MSG, and an

  6. Measurement of Temperature Fluctuations and Microscopic Growth Rates in a Silicon Floating Zone Under Microgravity (United States)

    Croell, Arne; Schweizer, Markus; Dold, P.; Kaiser, T.; Lichtensteiger, M.; Benz, K. W.


    USA Several microgravity experiments on sounding rockets and the Space Shuttle have shown that time-dependent thermocapillary (Marangoni) convection is the major cause for the formation of dopant striations in floating-zone grown semiconductor crystals, at least in small-scale systems not employing RF heating. To quantify this correlation, a silicon floating-zone experiment was performed during the TEXUS36 flight (February 7, 1998) in the monoellipsoid mirror furnace TEM02-ELLI. During the experiment, temperature fluctuations in the silicon melt zone and the microscopic growth rate were simultaneously measured. Temperature fluctuations of 0.5 C - 0.7 C with main frequencies between 0.1 Hz and 0.3 Hz were detectable. The microscopic growth rate fluctuated considerably around the average growth rate of 1 mm/min: rates from 4 mm/min to negative values (backmelting) were observed. Dopant striations are clearly visible in the Sb-doped crystal. They were characterized by Spreading Resistance measurements and Differential Interference Contrast microscopy. The frequencies associated with the dopant inhomogeneities correspond quite well with those of the temperature fluctuations and microscopic growth rates. 3D numerical simulations were performed to predict the optimum position of the temperature sensor, to evaluate characteristic temperature amplitudes and frequencies, and to give insight into the instability mechanisms of Marangoni convection in this configuration. The simulations were in good agreement with the experimental values, showing temperature fluctuations with frequencies ? 0.25 Hz and amplitudes up to 1.8 C at a position equivalent to that of the sensor tip in the experiment.

  7. Mechanics of Granular Materials (MGM) Microgravity Experiment (United States)

    Alshibli, Khalid A.; Sture, Stein


    The second series of MGM experiment was conducted during the STS-89 mission in January 1998. The experiment was previously flow on Atlantis's STS-79 mission in September 1996. Six displacement-controlled, drained triaxial compression experiments were performed at very low effective confining stresses. The confining stresses were in the ranges 0.05, 0.52 and 1.30 kPa. Three experiments were subjected to monotonic loading and unloading cycles while the other three experiments were subjected to cyclic loading. The results show very high peak strength friction angles in the range of 47.6 to 70.0 degrees, which are mainly due to overconsolidation and grain interlocking effects. It was observed that the residual strength levels in the monotonic loading experiments were in the same range as that observed at higher confining stress levels. The dilatancy angles were unusually high in the range of 30 to 31 degrees. All specimens display substantial initial stiffnesses and elastic moduli during unloading and reloading events, which are nearly an order of magnitude higher than conventional theories predict. A periodic instability phenomenon which appears to result from buckling of multiple internal arches and columnar systems, augmented by stick-slips was observed in the experiments. Computed Tomography (CT) measurements revealed valuable data about the internal fabric and the specimens deformation patterns. Uniform diffuse bifurcation with multiple radial shear bands was observed in the specimens tested in a microgravity environment. In the axial direction, two major conical surfaces were developed. Spatial nonsymmetrical deformations were observed in specimens tested in terrestrial laboratory.

  8. Viscosity of Xenon Examined in Microgravity (United States)

    Zimmerli, Gregory A.; Berg, Robert F.; Moldover, Michael R.


    Why does water flow faster than honey? The short answer, that honey has a greater viscosity, merely rephrases the question. The fundamental answer is that viscosity originates in the interactions between a fluid s molecules. These interactions are so complicated that, except for low-density gases, the viscosity of a fluid cannot be accurately predicted. Progress in understanding viscosity has been made by studying moderately dense gases and, more recently, fluids near the critical point. Modern theories predict a universal behavior for all pure fluids near the liquid-vapor critical point, and they relate the increase in viscosity to spontaneous fluctuations in density near this point. The Critical Viscosity of Xenon (CVX) experiment tested these theories with unprecedented precision when it flew aboard the Space Shuttle Discovery (STS-85) in August 1997. Near the critical point, xenon is a billion times more compressible than water, yet it has about the same density. Because the fluid is so "soft," it collapses under its own weight when exposed to the force of Earth s gravity - much like a very soft spring. Because the CVX experiment is conducted in microgravity, it achieves a very uniform fluid density even very close to the critical point. At the heart of the CVX experiment is a novel viscometer built around a small nickel screen. An oscillating electric field forces the screen to oscillate between pairs of electrodes. Viscosity, which dampens the oscillations, can be calculated by measuring the screen motion and the force applied to the screen. So that the fluid s delicate state near the critical point will not be disrupted, the screen oscillations are set to be both slow and small.

  9. Microgravity effect on endophytic bacteria communities of Triticum aestivum (United States)

    Qin, Youcai; Fu, Yuming; Chen, Huiwen; Liu, Hong; Sun, Yi


    Under normal gravity conditions, endophytic bacteria, one of the key bacterial community that inhabit in plant tissues, are well-known in promoting the plant growth and health, which are essential for long-term and long-distance manned microgravity space exploration. Here, we report how the Triticum aestivum endophytic bacterial communities behave differently under the simulated microgravity conditions. We demonstrate that, under simulated microgravity conditions, the microbial diversity in wheat seedling leaf increases while that in root decreases, compared to that cultivated under normal gravity conditions. We found that the dominant bacteria genus such as Pseudomonas, Paenibacillus and Bacillus significantly changes with gravity. The findings of this study provide important insight for space research, especially in terms of the Triticum aestivum cultivation in space.

  10. Estimated Muscle Loads During Squat Exercise in Microgravity Conditions (United States)

    Fregly, Christopher D.; Kim, Brandon T.; Li, Zhao; DeWitt, John K.; Fregly, Benjamin J.


    Loss of muscle mass in microgravity is one of the primary factors limiting long-term space flight. NASA researchers have developed a number of exercise devices to address this problem. The most recent is the Advanced Resistive Exercise Device (ARED), which is currently used by astronauts on the International Space Station (ISS) to emulate typical free-weight exercises in microgravity. ARED exercise on the ISS is intended to reproduce Earth-level muscle loads, but the actual muscle loads produced remain unknown as they cannot currently be measured directly. In this study we estimated muscle loads experienced during squat exercise on ARED in microgravity conditions representative of Mars, the moon, and the ISS. The estimates were generated using a subject-specific musculoskeletal computer model and ARED exercise data collected on Earth. The results provide insight into the capabilities and limitations of the ARED machine.

  11. Effects of microgravity on the mouse triceps brachii muscle. (United States)

    Ishihara, Akihiko; Nagatomo, Fumiko; Terada, Masahiro; Fujino, Hidemi; Kondo, Hiroyo; Ishioka, Noriaki


    In this study we investigated the effects of microgravity on the fiber properties of the mouse triceps brachii, a forelimb muscle that has no antigravity function. Mice (n = 7) were exposed to microgravity for 13 days on the space shuttle Atlantis (Space Transportation System-135). The fiber cross-sectional area (CSA) and succinate dehydrogenase (SDH) staining intensity of the triceps brachii muscle were compared with those of controls (n = 7). SDH activity in this muscle was also estimated. Microgravity did not affect the body weight, muscle weight, or fiber CSA, but there was reduced SDH staining intensity of all types of fibers, irrespective of the muscle region (P muscle SDH activity (P muscle of mice. © 2014 Wiley Periodicals, Inc.

  12. Collection and conversion of silicon furnace waste gas into higher value products: Phase 3, 6 MW pilot plant dc closed furnace technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Dosaj, V.D.


    The construction and operation of a 6 MW, closed dc furnace for smelting silicon was the primary focus of Phase 3. A 6 MW, dc closed furnace pilot plant was built in East Selkirk, Manitoba, Canada. The furnace is equipped with world`s most modern automatic control system used to control and monitor the process variables and operational data. This control system is suitable for commercial applications and could be used with either closed or open dc furnaces for smelting silicon or ferrosilicon. The construction was started in September 1990, and the facility was operational within 18 months. Following successful commissioning of the pilot plant in June 1992, twelve smelting test campaigns were conducted through November 1994.

  13. Numerical Investigation of Microgravity Tank Pressure Rise Due to Boiling (United States)

    Hylton, Sonya; Ibrahim, Mounir; Kartuzova, Olga; Kassemi, Mohammad


    The ability to control self-pressurization in cryogenic storage tanks is essential for NASAs long-term space exploration missions. Predictions of the tank pressure rise in Space are needed in order to inform the microgravity design and optimization process. Due to the fact that natural convection is very weak in microgravity, heat leaks into the tank can create superheated regions in the liquid. The superheated regions can instigate microgravity boiling, giving rise to pressure spikes during self-pressurization. In this work, a CFD model is developed to predict the magnitude and duration of the microgravity pressure spikes. The model uses the Schrage equation to calculate the mass transfer, with a different accommodation coefficient for evaporation at the interface, condensation at the interface, and boiling in the bulk liquid. The implicit VOF model was used to account for the moving interface, with bounded second order time discretization. Validation of the models predictions was carried out using microgravity data from the Tank Pressure Control Experiment, which flew aboard the Space Shuttle Mission STS-52. Although this experiment was meant to study pressurization and pressure control, it underwent boiling during several tests. The pressure rise predicted by the CFD model compared well with the experimental data. The ZBOT microgravity experiment is scheduled to fly on February 2016 aboard the ISS. The CFD model was also used to perform simulations for setting parametric limits for the Zero-Boil-Off Tank (ZBOT) Experiments Test Matrix in an attempt to avoid boiling in the majority of the test runs that are aimed to study pressure increase rates during self-pressurization. *Supported in part by NASA ISS Physical Sciences Research Program, NASA HQ, USA

  14. RWPV bioreactor mass transport: earth-based and in microgravity (United States)

    Begley, Cynthia M.; Kleis, Stanley J.


    Mass transport and mixing of perfused scalar quantities in the NASA Rotating Wall Perfused Vessel bioreactor are studied using numerical models of the flow field and scalar concentration field. Operating conditions typical of both microgravity and ground-based cell cultures are studied to determine the expected vessel performance for both flight and ground-based control experiments. Results are presented for the transport of oxygen with cell densities and consumption rates typical of colon cancer cells cultured in the RWPV. The transport and mixing characteristics are first investigated with a step change in the perfusion inlet concentration by computing the time histories of the time to exceed 10% inlet concentration. The effects of a uniform cell utilization rate are then investigated with time histories of the outlet concentration, volume average concentration, and volume fraction starved. It is found that the operating conditions used in microgravity produce results that are quite different then those for ground-based conditions. Mixing times for microgravity conditions are significantly shorter than those for ground-based operation. Increasing the differential rotation rates (microgravity) increases the mixing and transport, while increasing the mean rotation rate (ground-based) suppresses both. Increasing perfusion rates enhances mass transport for both microgravity and ground-based cases, however, for the present range of operating conditions, above 5-10 cc/min there are diminishing returns as much of the inlet fluid is transported directly to the perfusion exit. The results show that exit concentration is not a good indicator of the concentration distributions in the vessel. In microgravity conditions, the NASA RWPV bioreactor with the viscous pump has been shown to provide an environment that is well mixed. Even when operated near the theoretical minimum perfusion rates, only a small fraction of the volume provides less than the required oxygen levels

  15. Proteomic analysis of zebrafish embryos exposed to simulated-microgravity (United States)

    Hang, Xiaoming; Ma, Wenwen; Wang, Wei; Liu, Cong; Sun, Yeqing

    Microgravity can induce a serial of physiological and pathological changes in human body, such as cardiovascular functional disorder, bone loss, muscular atrophy and impaired immune system function, etc. In this research, we focus on the influence of microgravity to vertebrate embryo development. As a powerful model for studying vertebrate development, zebrafish embryos at 8 hpf (hour past fertilization) and 24 hpf were placed into a NASA developed bioreac-tor (RCCS) to simulate microgravity for 64 and 48 hours, respectively. The same number of control embryos from the same parents were placed in a tissue culture dish at the same temper-ature of 28° C. Each experiment was repeated 3 times and analyzed by two-dimensional (2-D) gel electrophoresis. Image analysis of silver stained 2-D gels revealed that 64 from total 292 protein spots showed quantitative and qualitative variations that were significantly (P<0.05) and reproducibly different between simulate-microgravity treatment and the stationary control samples. 4 protein spots with significant expression alteration (P<0.01) were excised from 2-D gels and analyzed by MALDI-TOF/TOF mass spectra primarily. Of these proteins, 3 down-regulated proteins were identified as bectin 2, centrosomal protein of 135kDa and tropomyosin 4, while the up-regulated protein was identified as creatine kinase muscle B. Other protein spots showed significant expression alteration will be identified successively and the corresponding genes expression will also be measured by Q-PCR method at different development stages. The data presented in this study illustrate that zebrafish embryo can be significantly induced by microgravity on the expression of proteins involved in bone and muscle formation. Key Words: Danio rerio; Simulated-microgravity; Proteomics

  16. 75 FR 64621 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Furnaces and... (United States)


    ... results which measure energy efficiency, energy use, * * * or estimated annual operating cost of a covered... representative annual operating cost for furnaces and boilers. For fossil-fueled furnaces and boilers, the annual operating cost is the sum of the annual electrical operating cost plus the annual fossil fuel cost. The July...

  17. Space Station Furnace Facility. Experiment/Facility Requirements Document (E/FRD), volume 2, appendix 5 (United States)

    Kephart, Nancy


    The function of the Space Station Furnace Facility (SSFF) is to support materials research into the crystal growth and solidification processes of electronic and photonic materials, metals and alloys, and glasses and ceramics. To support this broad base of research requirements, the SSFF will employ a variety of furnace modules operated, regulated, and supported by a core of common subsystems. Furnace modules may be reconfigured or specifically developed to provide unique solidifcation conditions for each set of experiments. The SSFF modular approach permits the addition of new or scaled-up furnace modules to support the evolution of the facility as new science requirements are identified. The SSFF Core is of modular design to permit augmentation for enhanced capabilities. The fully integrated configuration of the SSFF will consist of three racks with the capability of supporting up to two furnace modules per rack. The initial configuration of the SSFF will consist of two of the three racks and one furnace module. This Experiment/Facility Requirements Document (E/FRD) describes the integrated facility requirements for the Space Station Freedom (SSF) Integrated Configuration-1 (IC1) mission. The IC1 SSFF will consist of two racks: the Core Rack, with the centralized subsystem equipment, and the Experiment Rack-1, with Furnace Module-1 and the distributed subsystem equipment to support the furnace.

  18. Calculation of gas release from DC and AC arc furnaces in a foundry (United States)

    Krutyanskii, M. M.; Nekhamin, S. M.; Rebikov, E. M.


    A procedure for the calculation of gas release from arc furnaces is presented. The procedure is based on the stoichiometric ratios of the oxidation of carbon in liquid iron during the oxidation heat period and the oxidation of iron from a steel charge by oxygen in the period of solid charge melting during the gas exchange of the furnace cavity with the external atmosphere.

  19. Experimental and numerical study of MILD combustion in a lab-scale furnace

    NARCIS (Netherlands)

    Huang, X.; Tummers, M.J.; Roekaerts, D.J.E.M.; Scherer, Viktor; Fricker, Neil; Reis, Albino


    Mild combustion in a lab-scale furnace has been experimentally and numerically studied. The furnace was operated with Dutch natural gas (DNG) at 10 kW and at an equivalence ratio of 0.8. OH∗chemiluminescence images were taken to characterize the reaction zone. The chemiluminescence intensity is

  20. 78 FR 41265 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Furnaces and... (United States)


    ... full-fuel cycle as part of the residential furnace and boiler test procedure. (APGA, No. 7 at p. 1... Part 430 RIN 1904-AC96 Energy Conservation Program for Consumer Products: Test Procedures for... notice of proposed rulemaking (NOPR) to amend its test procedure for residential furnaces and boilers...

  1. Calculating analysis of firing different composition artificial coal liquid fuels (ACLF) in the cyclone primary furnace

    Energy Technology Data Exchange (ETDEWEB)

    Tsepenok, A. [Novosibirsk State Technological Univ. (Russian Federation); Joint Stock company ' ' ZiO-COTES' ' , Novosibirsk (Russian Federation); Ovchinnikov, Yu. [Novosibirsk State Technological Univ. (Russian Federation); Serant, F. [Joint Stock company ' ' ZiO-COTES' ' , Novosibirsk (Russian Federation)


    This chapter describes the preparation technologies, results of computer simulation of combustion processes in a cyclone primary furnace during firing of artificial coal liquid fuels prepared from different coal grades and results of live testing. As a result the values of unburned carbon, NO{sub x} emissions and other concentrations in the outlet section primary furnace were estimated.

  2. A Furnace for Diffraction Studies using Synchrotron X-Ray Radiation

    DEFF Research Database (Denmark)

    Buras, B.; Lebech, Bente; Kofoed, W.


    A furnace for diffraction studies using synchrotron X-ray radiation is described. The furnace can be operated between ambient temperature and 1 800 °C with a temperature stability better than 5 °C for temperatures above 300 °C. Kapton windows allow almost 360° access for the X-ray beam...

  3. Carbothermic reduction of electric arc furnace dust and calcination of waelz oxide by semi-pilot scale rotary furnace

    Directory of Open Access Journals (Sweden)

    Morcali M.H.


    Full Text Available The paper gives a common outline about the known recycling techniques from electric arc furnace dusts and describes an investigation of a pyrometallurgical process for the recovery of zinc and iron from electric arc furnace dusts (EAFD. In the waelz process, the reduction of zinc and iron from the waste oxides using solid carbon (lignite coal was studied. In the reduction experiments; temperature, time and charge type (powder and pellet were investigated in detail. It was demonstrated that zinc and iron recovery (% increases with increasing temperature as well as time. Pelletizing was found to be a better method than using the powder as received for the zinc recovery and iron conversion (. In the calcination (roasting process, crude zinc oxide, which evaporated from non-ferric metals were collected as condensed product (crude waelz oxide, was heated in air atmosphere. Lead, cadmium as well as chlorine and other impurities were successfully removed from crude waelz oxide by this method. In the calcination experiments; temperature and time are investigated in detail. It was demonstrated that zinc purification (% increases with increasing temperature. The highest zinc refining (% was obtained at 1200°C for 120 minutes. A kinetic study was also undertaken to determine the activation energy of the process. Activation energies were 242.77 kJ/mol for the zinc recovery with powder forms, 261.99 kJ/mol for the zinc recovery with pellet forms respectively. It was found that, initially, the reaction was chemically controlled.

  4. Vacuum transitions and eternal inflation (United States)

    Johnson, Matthew C.

    In this thesis, we focus on aspects of inflation and eternal inflation arising in scalar field theories coupled to gravity which possess a number of metastable states. Such theories contain instantons that interpolate between the metastable potential minima, corresponding to the nucleation of bubbles containing a new phase in a background of the old phase. In the first part of this thesis, we describe the classical dynamics and quantum nucleation of vacuum bubbles. We classify all possible spherically symmetric, thin-wall solutions with arbitrary interior and exterior cosmological constant, and find that bubbles possessing a turning point are unstable to aspherical perturbations. Next, we turn to the quantum nucleation of bubbles with zero mass. Focusing on instantons interpolating between positive and negative energy minima, we find that there exists a "Great Divide" in the space of potentials, across which the lifetime of metastable states differs drastically. Generalizing a semi-classical Hamiltonian formalism to treat the nucleation of bubbles with nonzero mass, we show that a number of tunneling mechanisms can be unified in the thin-wall limit, and directly compare their probabilities. In the second part of this thesis, we discuss the measure problem in eternal inflation. We give a detailed analysis of the prospects for making predictions in eternal inflation, and describe the existing probability measures and the connections between them. We then show that all existing measures exhibit a number of rather generic phenomena, for example strongly weighting vacua that can undergo rapid transitions between each other. It is argued that making predictions will require a measure that weights histories as opposed to vacua, and we develop a formalism to addresses this. Finally, we assess the prospects for observing collisions between vacuum bubbles in an eternally inflating universe. Contrary to conventional wisdom, we find that under certain assumptions most

  5. CC Cryostat Vacuum Pumping Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, J.B.; /Fermilab


    This report calculates the effect of the conductances of the pumping lines on the pumping speeds of the vacuum pumps being used to pump the inner vessel, and annular space, vacuum tight during the CC Cryostat testing. Effective pumping speeds were calculated for various values of pressure via the above stated formulas (see calculations). Conductances of valves, elbows, and tees were calculated with the help of ref. 1, and the volumes of the inner vessel and annular space were calculated wtth the aid of ref. 2. The major results of these calculations follow. The attached graphs show the effective pumping speed vs. pressure, as well as the pressure vs. pumpdown time for both the inner vessel pumpdown and the annular space pumpdown. Many intervals of pressure were chosen in order to give a complete picture of the effects on the pumping speed, and pumpdown time. An important rule of thumb is that the effective pumping speed be close to the intrinsic pump speed in the region of interest for the best efficiency. With an infinite conductance, these quantities become equal. In the case of the annular space pumpdown. the effective pumping speed is within approximately 15% of the intrinsic pump speed for pressures down to 6000{mu}, and at that point, the conductance effects slow the system down and provide a 49% difference at 1000{mu}. To Improve these numbers, the line length must be shortened, or even better, the line diameter increased. As far as pumpdown time is concerned, the actual pumpdown was completed in a reasonable amount of time, and would have been even better if the pumping system did not lag due to a leaK and its repair time. The inner vessel pumpdown shows a pumpdown time near 1 hour to reach 100{mu} pressure. The effective pumping speed matches to within 10% of the intrinsic pump speed to 6000{mu}, and then the conductance effects become more important and provide a 41% difference at 1000{mu}. The actual pumpdown was completed in a reasonable amount of time

  6. Investigations of field instability of ferrofluid in hypergravity and microgravity

    Directory of Open Access Journals (Sweden)

    Theng Yee Chong


    Full Text Available The field instability of the free surface of ferrofluid was investigated under microgravity and hypergravity environments conducted by parabolic flight. It is observed that the perturbation was suppressed under hypergravity, whereas at the microgravity condition, it appeared to have only slight increase in the amplitude of the perturbation peaks compared to the case of ground condition. Besides, an observation of peak-trough distance showed that not only the peak, but the trough was also very much dependent on the applied magnetic field. The difference of magnetic pole (north and south had shown to be a factor to the perturbation as well.

  7. Modeled microgravity inhibits apoptosis in peripheral blood lymphocytes (United States)

    Risin, D.; Pellis, N. R.; McIntire, L. V. (Principal Investigator)


    Microgravity interferes with numerous lymphocyte functions (expression of cell surface molecules, locomotion, polyclonal and antigen-specific activation, and the protein kinase C activity in signal transduction). The latter suggests that gravity may also affect programmed cell death (PCD) in lymphocyte populations. To test this hypothesis, we investigated spontaneous, activation- and radiation-induced PCD in peripheral blood mononuclear cells exposed to modeled microgravity (MMG) using a rotating cell culture system. The results showed significant inhibition of radiation- and activation-induced apoptosis in MMG and provide insights into the potential mechanisms of this phenomenon.

  8. A numerical study of biofilm growth in a microgravity environment (United States)

    Aristotelous, A. C.; Papanicolaou, N. C.


    A mathematical model is proposed to investigate the effect of microgravity on biofilm growth. We examine the case of biofilm suspended in a quiescent aqueous nutrient solution contained in a rectangular tank. The bacterial colony is assumed to follow logistic growth whereas nutrient absorption is assumed to follow Monod kinetics. The problem is modeled by a coupled system of nonlinear partial differential equations in two spatial dimensions solved using the Discontinuous Galerkin Finite Element method. Nutrient and biofilm concentrations are computed in microgravity and normal gravity conditions. A preliminary quantitative relationship between the biofilm concentration and the gravity field intensity is derived.

  9. Shape Evolution of Detached Bridgman Crystals Grown in Microgravity (United States)

    Volz, M. P.; Mazuruk, K.


    A theory describing the shape evolution of detached Bridgman crystals in microgravity has been developed. A starting crystal of initial radius r0 will evolve to one of the following states: Stable detached gap; Attachment to the crucible wall; Meniscus collapse. Only crystals where alpha plus omega is great than 180 degrees will achieve stable detached growth in microgravity. Results of the crystal shape evolution theory are consistent with predictions of the dynamic stability of crystallization (Tatarchenko, Shaped Crystal Growth, Kluwer, 1993). Tests of transient crystal evolution are planned for ICESAGE, a series of Ge and GeSi crystal growth experiments planned to be conducted on the International Space Station (ISS).

  10. CATE: A Case Study of an Interdisciplinary Student-Led Microgravity Experiment (United States)

    Colwell, J. E.; Dove, A.; Lane, S. S.; Tiller, C.; Whitaker, A.; Lai, K.; Hoover, B.; Benjamin, S.


    The Collisional Accretion Experiment (CATE) was designed, built, and flown on NASA's C-9 parabolic flight airplane in less than a year by an interdisciplinary team of 6 undergraduate students under the supervision of two faculty. CATE was selected in the initial NASA Undergraduate Student Instrument Project (USIP) solicitation in the Fall of 2013, and the experiment flight campaign was in July 2014. The experiment studied collisions between different particle populations at low velocities (sub-m/s) in a vacuum and microgravity to gain insight into processes in the protoplanetary disk and planetary ring systems. Faculty provided the experiment concept and key experiment design parameters, and the student team developed the detailed hardware design for all components, manufactured and tested hardware, operated the experiment in flight, and analyzed data post-flight. Students also developed and led an active social media campaign and education and public outreach campaign to engage local high school students in the project. The ability to follow an experiment through from conception to flight was a key benefit for undergraduate students whose available time for projects such as this is frequently limited to their junior and senior years. Key factors for success of the program included having an existing laboratory infrastructure and experience in developing flight payloads and an intrinsically simple experiment concept. Students were highly motivated, in part, by their sense of technical and scientific ownership of the project, and this engagement was key to the project's success.

  11. Determination of Interfacial Rheological Properties through Microgravity Oscillations of Bubbles and Drops (United States)

    Nadim, Ali; Rush, Brian M.


    This report summarizes our derivations of analytical expressions for the frequencies and damping constants for small-amplitude axisymmetric shape oscillations of a liquid drop suspended in an immiscible fluid host in microgravity. In particular, this work addresses large Reynolds number shape oscillations and focuses on the surface rheological effects that arise from the presence of insoluble surfactants at the interface. Parameters characterizing viscous effects from the bulk phases, surface viscous effects, Marangoni effects from the surface advection and diffusion of surfactants, and the Gibbs elasticity are all considered and analyzed to determine the relative importance of each contribution. Supplementing the analytical treatment for small-amplitude oscillations, a numerical boundary integral equation formulation is developed for the study of large-amplittide axisymmetric oscillations of a drop in vacuum. The boundary integral formulation is an extension of classical potential flow theory and approximately accounts for viscous effects in the bulk fluid as well as the surface viscous and Marangoni effects resulting from an insoluble surfactant contaminating the interface. Theoretical and numerical results are presented for four distinct cases. These, range from the case when the effects of the surfactants are 'negligible' to 'large' when compared to the viscous effects in the bulk phases. The feasibility of the non-contact measurement of the surface parameters, using experimental observations for the oscillation frequencies and damping constants of drops and bubbles, is discussed.

  12. Modeling of glass fusion furnaces; Modelisation des fours de fusion de verre

    Energy Technology Data Exchange (ETDEWEB)

    Mechitoua, N. [Electricite de France (EDF), 78 - Chatou (France). Direction des Etudes et Recherches; Plard, C. [Electricite de France, 77 - Moret sur Loing (France). Direction des Etudes et Recherches


    The furnaces used for glass melting are industrial installations inside which complex and coupled physical and chemical phenomena occur. Thermal engineering plays a major role and numerical simulation is a precious tool for the analysis of the different coupling, of their interaction and of the influence of the different parameters. In order to optimize the functioning of glass furnaces and to improve the quality of the glass produced, Electricite de France (EdF) has developed a specialized version of the ESTET fluid mechanics code, called `Joule`. This paper describes the functioning principle of glass furnaces, the interactions between heat transfers and flows inside the melted glass, the interactions between heat transfers and the thermal regulation of the furnace, the interactions between heat transfers and glass quality and the heat transfer interactions between the melted glass, the furnace walls and the combustion area. (J.S.)

  13. Integration of Tuyere, Raceway and Shaft Models for Predicting Blast Furnace Process (United States)

    Fu, Dong; Tang, Guangwu; Zhao, Yongfu; D'Alessio, John; Zhou, Chenn Q.


    A novel modeling strategy is presented for simulating the blast furnace iron making process. Such physical and chemical phenomena are taking place across a wide range of length and time scales, and three models are developed to simulate different regions of the blast furnace, i.e., the tuyere model, the raceway model and the shaft model. This paper focuses on the integration of the three models to predict the entire blast furnace process. Mapping output and input between models and an iterative scheme are developed to establish communications between models. The effects of tuyere operation and burden distribution on blast furnace fuel efficiency are investigated numerically. The integration of different models provides a way to realistically simulate the blast furnace by improving the modeling resolution on local phenomena and minimizing the model assumptions.

  14. Investigation of Voltage Unbalance Problems In Electric Arc Furnace Operation Model

    Directory of Open Access Journals (Sweden)

    Yacine DJEGHADER


    Full Text Available In modern steel industry, Electric Arc Furnaces are widely used for iron and scarp melting. The operation of electric arc furnace causes many power quality problems such as harmonics, unbalanced voltage and flicker. The factors that affect Electric arc furnace operation are the melting or refining materials, melting stage, electrodes position (arc length, electrode arm control and short circuit power of the feeder, so, arc voltages, current and power are defined as a nonlinear function of arc length. This study focuses on investigation of unbalanced voltage due to Electrics Arc Furnace operation mode. The simulation results show the major problem of unbalanced voltage affecting secondary of furnace transformer is caused by the different continues movement of electrodes.

  15. Minimization of Blast furnace Fuel Rate by Optimizing Burden and Gas Distribution

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Chenn Zhou


    The goal of the research is to improve the competitive edge of steel mills by using the advanced CFD technology to optimize the gas and burden distributions inside a blast furnace for achieving the best gas utilization. A state-of-the-art 3-D CFD model has been developed for simulating the gas distribution inside a blast furnace at given burden conditions, burden distribution and blast parameters. The comprehensive 3-D CFD model has been validated by plant measurement data from an actual blast furnace. Validation of the sub-models is also achieved. The user friendly software package named Blast Furnace Shaft Simulator (BFSS) has been developed to simulate the blast furnace shaft process. The research has significant benefits to the steel industry with high productivity, low energy consumption, and improved environment.



    V. I. Timoshpolskiy; I. A. Trusova; D. V. Mendelev


    The main schemes of recovery of waste gases heat, applied in fuel furnaces of metallurgical and machinebuilding production, are analysed, and also criteria of choice of recuperators construction depending on function and constructions of furnaces are considered.


    Directory of Open Access Journals (Sweden)

    V. I. Timoshpolskiy


    Full Text Available The main schemes of recovery of waste gases heat, applied in fuel furnaces of metallurgical and machinebuilding production, are analysed, and also criteria of choice of recuperators construction depending on function and constructions of furnaces are considered.

  18. A combined arc-melting and tilt-casting furnace for the manufacture of high-purity bulk metallic glass materials (United States)

    Soinila, E.; Pihlajamäki, T.; Bossuyt, S.; Hänninen, H.


    An arc-melting furnace which includes a tilt-casting facility was designed and built, for the purpose of producing bulk metallic glass specimens. Tilt-casting was chosen because reportedly, in combination with high-purity processing, it produces the best fatigue endurance in Zr-based bulk metallic glasses. Incorporating the alloying and casting facilities in a single piece of equipment reduces the amount of laboratory space and capital investment needed. Eliminating the sample transfer step from the production process also saves time and reduces sample contamination. This is important because the glass forming ability in many alloy systems, such as Zr-based glass-forming alloys, deteriorates rapidly with increasing oxygen content of the specimen. The challenge was to create a versatile instrument, in which high purity conditions can be maintained throughout the process, even when melting alloys with high affinity for oxygen. Therefore, the design provides a high-vacuum chamber to be filled with a low-oxygen inert atmosphere, and takes special care to keep the system hermetically sealed throughout the process. In particular, movements of the arc-melting electrode and sample manipulator arm are accommodated by deformable metal bellows, rather than sliding O-ring seals, and the whole furnace is tilted for tilt-casting. This performance of the furnace is demonstrated by alloying and casting Zr55Cu30Al10Ni5 directly into rods up to ø 10 mm which are verified to be amorphous by x-ray diffraction and differential scanning calorimetry, and to exhibit locally ductile fracture at liquid nitrogen temperature.

  19. Impacts on Dissipative Sonic Vacuum (United States)

    Xu, Yichao; Nesterenko, Vitali

    We investigate the propagating compression bell shape stress waves generated by the strikers with different masses impacting the sonic vacuum - the discrete dissipative strongly nonlinear metamaterial with zero long wave sound speed. The metamaterial is composed of alternating steel disks and Nitrile O-rings. Being a solid material, it has exceptionally low speed of the investigated stress waves in the range of 50 - 74 m/s, which is a few times smaller than the speed of sound or shock waves in air generated by blast. The shape of propagating stress waves was dramatically changed by the viscous dissipation. It prevented the incoming pulses from splitting into trains of solitary waves, a phenomenon characteristic of the non-dissipative strongly nonlinear discrete systems when the striker mass is larger than the cell mass. Both high-speed camera images and numerical simulations demonstrate the unusual rattling behavior of the top disk between the striker and the rest of the system. The linear momentum and energy from the striker were completely transferred to the metamaterial. This strongly nonlinear dissipative metamaterial can be designed for the optimal attenuation of dynamic loads generated by impact or contact explosion. Author 1 wants to acknowledge the support provided by UCSD.

  20. Vacuum-Ultraviolet Photovoltaic Detector. (United States)

    Zheng, Wei; Lin, Richeng; Ran, Junxue; Zhang, Zhaojun; Ji, Xu; Huang, Feng


    Over the past two decades, solar- and astrophysicists and material scientists have been researching and developing new-generation semiconductor-based vacuum ultraviolet (VUV) detectors with low power consumption and small size for replacing traditional heavy and high-energy-consuming microchannel-detection systems, to study the formation and evolution of stars. However, the most desirable semiconductor-based VUV photovoltaic detector capable of achieving zero power consumption has not yet been achieved. With high-crystallinity multistep epitaxial grown AlN as a VUV-absorbing layer for photogenerated carriers and p-type graphene (with unexpected VUV transmittance >96%) as a transparent electrode to collect excited holes, we constructed a heterojunction device with photovoltaic detection for VUV light. The device exhibits an encouraging VUV photoresponse, high external quantum efficiency (EQE) and extremely fast tempera response (80 ns, 10 4 -10 6 times faster than that of the currently reported VUV photoconductive devices). This work has provided an idea for developing zero power consumption and integrated VUV photovoltaic detectors with ultrafast and high-sensitivity VUV detection capability, which not only allows future spacecraft to operate with longer service time and lower launching cost but also ensures an ultrafast evolution of interstellar objects.

  1. Decarburization and Inclusion Removal Process in Single Snorkel Vacuum Degasser (United States)

    Dian-Qiao, Geng; Lei, Hong; He, Ji-Cheng


    In the current work, the coupled mathematical models for decarburization, fluid flow model and inclusion collision-aggregation model were solved to investigate the spatial distribution of carbon, inclusion's collision-aggregation and removal in a single snorkel vacuum refining furnace (SSF). The numerical results show that the turbulence kinetic energy of ladle in SSF is much greater than that in RH, which can shrink the dead zone and prompt the mixing in the ladle. The overall decarburization reaction rate can be described as a first-order reaction. On the condition of the same gas flow rate, the volumetric mass transfer coefficient for decarburization in SSF is almost twenty times bigger than that in RH, which leads to a much greater decarburization rate in SSF. The spatial distribution of carbon mass fraction in SSF is quite different from that in RH. There is the greater mass fraction of carbon at the recirculation zone under up-snorkel in RH, but this phenomenon disappears in SSF. The inclusion removal can be simplified as the mass transfer between liquid steel to slag, refractory wall and bubble surface. And the overall inclusion removal rate can be regarded as a first-order reaction. The volumetric mass transfer coefficient for inclusion removal in SSF is about three times as that in RH, the inclusion removal rate in SSF is greater than that in RH. The inclusions with different size have different removal rates in SSF. For inclusion flotation after deoxidization, the treatment time in SSF is less than that in RH.

  2. Reports on research achievements in developing high-performance industrial furnaces in fiscal 1998 (Research and development of high-performance industrial furnaces). Volume 1; 1998 nendo koseino kogyoro nado ni kansuru kenkyu kaihatsu seika hokokusho. 1

    Energy Technology Data Exchange (ETDEWEB)



    From the reports on research achievements in developing high-performance industrial furnaces in fiscal 1998, the report volume 1 was prepared as a research achievement report of each working group, detailing fundamental researches, heating furnaces, and heat treatment furnaces. The fundamental researches have researched combustion evaluating technology, characteristics of the area in the vicinity of a combustor, characteristics of combustion of high-temperature air, heating characteristics of a furnace to investigate effect of local heat absorption, and combustion evaluation. For the heating furnaces, the following subjects were studied: development of an in-furnace combustion model, summary of an experiment for evaluating high-temperature air combustion, furnace height relative to combustion heat transfer characteristics, heat loss minimizing technology, combustion heat transfer characteristics of liquid fuels, optimal operation of the high-temperature air combustion, basic control in heating control, and steel piece heating control. Studies were performed for the heat treatment furnaces on the case of a direct firing furnace in evaluating the heat transfer characteristics, the case of a radiant tube furnace, application of thermal fluid simulation technology, furnace averaging technology, soot reducing technology, control technology, and trial design on a high-performance heat treatment furnace. (NEDO)

  3. Some aspects of vacuum ultraviolet radiation physics

    CERN Document Server

    Damany, Nicole; Vodar, Boris


    Some Aspects of Vacuum Ultraviolet Radiation Physics presents some data on the state of research in vacuum ultraviolet radiation in association with areas of physics. Organized into four parts, this book begins by elucidating the optical properties of solids in the vacuum ultraviolet region (v.u.v.), particularly the specific methods of determination of optical constants in v.u.v., the properties of metals, and those of ionic insulators. Part II deals with molecular spectroscopy, with emphasis on the spectra of diatomic and simple polyatomic molecules, paraffins, and condensed phases. Part III

  4. Ultra-high vacuum technology for accelerators

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit; Hilleret, Noël; Strubin, Pierre M


    The lectures will start with a review of the basics of vacuum physics required to build Ultra High Vacuum (UHV) systems, such as static and dynamic outgassing. Before reviewing the various pumping and measurement devices, including the most modern one like Non Evaporable Getter (NEG) coatings, an overview of adequate materials to be used in UHV systems will be given together with their treatment (e.g. cleaning procedures and bake out). Practical examples based on existing or future accelerators will be used to illustrate the topics. Finally, a short overview of modern vacuum controls and interlocks will be given.

  5. Vacuum engineering, calculations, formulas, and solved exercises

    CERN Document Server

    Berman, Armand


    This book was written with two main objectives in mind-to summarize and organize the vast material of vacuum technology in sets of useful formulas, and to provide a collection of worked out exercises showing how to use these formulas for solving technological problems. It is an ideal reference source for those with little time to devote to a full mathematical treatment of the many problems issued in vacuum practice, but who have a working knowledge of the essentials of vacuum technology, elementary physics, and mathematics. This time saving book employs a problem-solving approach throughout, p

  6. Radiation of superluminal sources in vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Bolotovskii, B.M. [P.N. Lebedev Physical Institute, Leninsky prospect 53, Moscow 119991 (Russian Federation)]. E-mail:; Serov, A.V. [P.N. Lebedev Physical Institute, Leninsky prospect 53, Moscow 119991 (Russian Federation)]. E-mail:


    Vavilov-Cherenkov radiation is emitted by a charged body uniformly moving in a medium when the body velocity exceeds that of light in the medium. Therefore, it was believed that Vavilov-Cherenkov radiation is impossible in vacuum, because the velocity of any material body cannot exceed the light velocity in vacuum. However, it is possible to realize distributions of charges and currents which propagate with any given velocity. Such a superluminal distribution can be used as a source of Vavilov-Cherenkov radiation in vacuum.

  7. Report of the Synchrotron Radiation Vacuum Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Avery, R.T.


    The Synchrotron Radiation Vacuum Workshop was held to consider two vacuum-related problems that bear on the design of storage rings and beam lines for synchrotron radiation facilities. These problems are gas desorption from the vacuum chamber walls and carbon deposition on optical components. Participants surveyed existing knowledge on these topics and recommended studies that should be performed as soon as possible to provide more definitive experimental data on these topics. This data will permit optimization of the final design of the Advanced Light Source (ALS) and its associated beam lines. It also should prove useful for other synchrotron radiation facilities as well.

  8. Gases and vacua handbook of vacuum physics

    CERN Document Server

    Beck, A H


    Handbook of Vacuum Physics, Volume 1: Gases and Vacua presents three major topics, which are the fourth to sixth parts of this volume. These topics are the remarks on units of physical quantities; kinetic theory of gases and gaseous flow; and theory of vacuum diffusion pumps. The first topic aims to present concisely the significance of units of physical quantities, catering the need and interest of those who take measurements and make calculations in different fields of vacuum sciences. The technique and applications of this particular topic are also provided. The second main topic focuses sp

  9. The fine art of preparing a vacuum

    CERN Multimedia


    The vacuum chambers, or beam pipes, of the LHC experiments are located right at the interface between the detectors and the accelerator, and are therefore crucial to the LHC project as a whole. In this domain, the ALICE and CMS experiments have just passed an important milestone, with the completion of the first of CMS's two end-cap vacuum chambers, together with the completion and bakeout of an 18-metre section of the ALICE vacuum chamber. These complex projects, for which CERN's AT/VAC Group is responsible, involved dozens of people over a number of years.

  10. Coke properties in simulated blast furnace conditions:investigation on hot strength, chemical reactivity and reaction mechanism


    Haapakangas, J. (Juho)


    Abstract The blast furnace – basic oxygen furnace route remains the most utilised process route in the production of steel worldwide. Coke is the main fuel of the blast furnace process, however, coke producers and blast furnace operators are facing significant challenges due to increased demands on coke quality and decrease of prime coking coals. The estimation of coke performance in the industrial process through accurate laboratory analyses is of increasing importance. In this doctor...


    Energy Technology Data Exchange (ETDEWEB)

    Pierce, R.; Pak, D.


    Vacuum distillation of chloride salts from plutonium oxide (PuO{sub 2}) and simulant PuO{sub 2} has been previously demonstrated at Department of Energy (DOE) sites using kilogram quantities of chloride salt. The apparatus for vacuum distillation contains a zone heated using a furnace and a zone actively cooled using either recirculated water or compressed air. During a vacuum distillation operation, a sample boat containing the feed material is placed into the apparatus while it is cool, and the system is sealed. The system is evacuated using a vacuum pump. Once a sufficient vacuum is attained, heating begins. Volatile salts distill from the heated zone to the cooled zone where they condense, leaving behind the non-volatile materials in the feed boat. The application of vacuum salt distillation (VSD) is of interest to the HB-Line Facility and the MOX Fuel Fabrication Facility (MFFF) at the Savannah River Site (SRS). Both facilities are involved in efforts to disposition excess fissile materials. Many of these materials contain chloride and fluoride salt concentrations which make them unsuitable for dissolution without prior removal of the chloride and fluoride salts. Between September 2009 and January 2011, the Savannah River National Laboratory (SRNL) and HB-Line designed, developed, tested, and successfully deployed a system for the distillation of chloride salts. Subsequent efforts are attempting to adapt the technology for the removal of fluoride. Fluoride salts of interest are less-volatile than the corresponding chloride salts. Consequently, an alternate approach is required for the removal of fluoride without significantly increasing the operating temperature. HB-Line Engineering requested SRNL to evaluate and demonstrate the feasibility of an alternate approach using both non-radioactive simulants and plutonium-bearing materials. Whereas the earlier developments targeted the removal of sodium chloride (NaCl) and potassium chloride (KCl), the current

  12. Vacuum-sintered body of a novel apatite for artificial bone (United States)

    Tamura, Kenichi; Fujita, Tatsushi; Morisaki, Yuriko


    We produced regenerative artificial bone material and bone parts using vacuum-sintered bodies of a novel apatite called "Titanium medical apatite (TMA®)" for biomedical applications. TMA was formed by chemically connecting a Ti oxide molecule with the reactive [Ca10(PO4)6] group of Hydroxyapatite (HAp). The TMA powders were kneaded with distilled water, and solid cylinders of compacted TMA were made by compression molding at 10 MPa using a stainless-steel vessel. The TMA compacts were dried and then sintered in vacuum (about 10-3 Pa) or in air using a resistance heating furnace in the temperature range 1073-1773 K. TMA compacts were sintered at temperatures greater than 1073 K, thus resulting in recrystallization. The TMA compact bodies sintered in the range 1273-1773 K were converted into mixtures composed of three crystalline materials: α-TCP (tricalcium phosphate), β-TCP, and Perovskite-CaTiO3. The Perovskite crystals were stable and hard. In vacuum-sintering, the Perovskite crystals were transformed into fibers (approximately 1 µm in diameter × 8 µm in length), and the fiber distribution was uniform in various directions. We refer to the TMA vacuum-sintered bodies as a "reinforced composite material with Perovskite crystal fibers." However, in atmospheric sintering, the Perovskite crystals were of various sizes and were irregularly distributed as a result of the effect of oxygen. After sintering temperature at 1573 K, the following results were obtained: the obtained TMA vacuum-sintered bodies (1) were white, (2) had a density of approximately 2300 kg/m3 (corresponding to that of a compact bone or a tooth), and had a thermal conductivity of approximately 31.3 W/(m·K) (corresponding to those of metal or ceramic implants). Further, it was possible to cut the TMA bodies into various forms with a cutting machine. An implant made of TMA and inserted into a rabbit jaw bone was covered by new bone tissues after just one month because of the high

  13. [Multi-spectral measurement of Basic oxygen furnace flame temperature]. (United States)

    Wang, Yong-Qing; Chen, Yan-Ru; Zhao, Qi; Chen, Fei-Nan; Chen, Jing-Jing


    A multi-wavelength analysis method is introduced to measure the temperature of basic oxygen furnace flame. In this study, USB4000 spectrometer was applied to obtain radiation spectrum of flame within wavelength range 200-1 100 nm, from which the flame temperature and monochromatic emissivity was derived by Levenberg-Marquart modeling method. Wavelet neural network was applied to process the spectral measurement data, which could cancel the assumption model of emissivity and wavelengths. It is a kind of valid method to acquire the true temperature and spectral emissivity. Each neuron in the hidden layer of a feed-forward network is a combination of the sigmoidal activation function (SAF) and morlet wavelet activation function (WAF). The output of the hidden neuron is the product of the output from these two activation functions.

  14. Oxidation Character of Carbon Composite Bricks Used in Blast Furnace (United States)

    Zuo, Haibin; Wang, Cong; Zhang, Jianliang; Jiao, Kexin; Zhao, Yongan

    The carbon composite brick is a new refractory used in blast furnace hearth and bottom. It caused wide attention due to its high thermal conductivity and low erosion by molten iron. In this paper, chemical constituents, SEM-EDS and X-ray diffraction were carried out in order to understand reaction mechanisms. A series of experiments of oxidation resistance characteristics were made. The oxidation mechanisms of carbon composite bricks in the presence of air were analyzed. According to the analysis on many experimental results, the oxidation process of carbon composite bricks under different temperatures were controlled by different mechanisms. In the condition of high temperature, SiO2 as oxidation product hindered the diffusion of O2, and reduced the oxidation loss of graphite in the internal.

  15. Modeling of Radiative Heat Transfer in an Electric Arc Furnace (United States)

    Opitz, Florian; Treffinger, Peter; Wöllenstein, Jürgen


    Radiation is an important means of heat transfer inside an electric arc furnace (EAF). To gain insight into the complex processes of heat transfer inside the EAF vessel, not only radiation from the surfaces but also emission and absorption of the gas phase and the dust cloud need to be considered. Furthermore, the radiative heat exchange depends on the geometrical configuration which is continuously changing throughout the process. The present paper introduces a system model of the EAF which takes into account the radiative heat transfer between the surfaces and the participating medium. This is attained by the development of a simplified geometrical model, the use of a weighted-sum-of-gray-gases model, and a simplified consideration of dust radiation. The simulation results were compared with the data of real EAF plants available in literature.

  16. Pragmatic analysis of the electric submerged arc furnace continuum (United States)

    Karalis, K.; Karkalos, N.; Antipas, G. S. E.; Xenidis, A.


    A transient mathematical model was developed for the description of fluid flow, heat transfer and electromagnetic phenomena involved in the production of ferronickel in electric arc furnaces. The key operating variables considered were the thermal and electrical conductivity of the slag and the shape, immersion depth and applied electric potential of the electrodes. It was established that the principal stimuli of the velocities in the slag bath were the electric potential and immersion depth of the electrodes and the thermal and electrical conductivities of the slag. Additionally, it was determined that, under the set of operating conditions examined, the maximum slag temperature ranged between 1756 and 1825 K, which is in accordance with industrial measurements. Moreover, it was affirmed that contributions to slag stirring due to Lorentz forces and momentum forces due to the release of carbon monoxide bubbles from the electrode surface were negligible.

  17. Optimisation of metal charge material for electric arc furnace

    Directory of Open Access Journals (Sweden)

    T. Lis


    Full Text Available The analysis of the changes in the crude steel production volumes implies gradual increase of production since the mid 20th century. This tendency has been slightly hampered by the economic depression. At the same time, the market requirements enforce improvement of the quality of the products manufactured on simultaneous minimisation of the production costs. One of the tools applied to solve these problems is mathematical optimisation. The author of this paper has presented an example of application of the multi-criteria optimisation method to improvement of efficiency of steel smelting in an electric arc furnace (EAF through appropriate choice of the charge scrap. A measurable effect of applying such a methodology of choosing the metal charge is the ability to reduce the unit cost of steel smelting.

  18. Practical Active Disturbance Rejection Solution for Furnace Temperature Control System

    Directory of Open Access Journals (Sweden)

    Jian Huan Su


    Full Text Available A practical active disturbance rejection control (ADRC solution is proposed for the furnace temperature system. Employing a linear reduced-order model with optimized parameters, the practical ADRC is simple to use, easy to tune and energy-efficient in dealing with the uncertainties and disturbances in plant dynamics. Through the order reduction in both the plant model and the state observer, we develop a first order extended state observer for estimating in real-time the total value of the external and internal disturbances. The practical and standard ADRCs outperform the Smith Predictor and the PID controller in disturbance-rejection and robustness; however, the practical ADRC has fewer adjustable parameters and significantly smaller energy consumption than the standard ADRC, making it a viable candidate for industrial applications.

  19. Characterization of a Mono-Ellipsoidal Imaging Furnace

    Energy Technology Data Exchange (ETDEWEB)

    Guesdon, C.; Alxneit, I.; Tschudi, H.R.; Wuillemin, D.; Brunner, Y.; Winkel, L.; Sturzenegger, M.


    An imaging furnace was built and tested for investigating chemical reactions that involve melts and the release of condensable gases. A key feature is the sample stage with a water-cooled sample support to avoid reaction of the sample with crucible material. A built-in hammer allows for freezing the high-temperature composition of the sample and a glass dome above the sample allows for experiments under defined atmospheres. Measured peak flux densities on samples with a diameter of 5 mm clearly exceed 500 Wcm{sub -2} producing sample temperatures of at least 2500 K. Cold experiments with a smoke source at the place of the sample as well as decomposition experiments with chalcocite (Cu{sub 2}S) proved that an appropriate gas flow through the dome keeps the dome free of condensates. (author)

  20. A Review of Granulation Process for Blast Furnace Slag

    Directory of Open Access Journals (Sweden)

    Yu Pengfei


    Full Text Available Molten slags of blast furnace is a second resources with great value of 1600~1 800 MJ sensible heat per ton. At present, water-quenching process plays a leading role in recovering waste heat of the molten slags. However, this method not only cost lots of water, but also recover little sensible heat and can pollute the surrounding environment. Dry granulation process, as an environmentally friendly method with high-efficiency heat recovery, have attracted widespread attentions. In this paper, the water quenching and dry granulation processes were discussed in detail. After a thorough comparative analysis of various treatment technologies, it can be concluded that centrifugal granulation affiliated with dry granulation is the optimum process, with smaller slag particle size (about 2mm, more glassy phase and higher recovery rate.

  1. Iron loss in high-power arc steelmaking furnaces

    Directory of Open Access Journals (Sweden)

    V. P. Karasyov


    Full Text Available There is considered the power operating mode of a high-power arc steelmaking furnaces (ASMF in the period of the flat bath. It is revealed that electric energy is mainly spent for heating and overheating the foamed slag. Heat transferring from slag to metal is carried out by the convective agitation of the bath. For agitation there is used intensive purging of the bath with oxygen that causes increased iron losses with the running foamed slag. There are noted the negative points of working with the foamed slag. It is recommended to expand R&D in the field of optimizing the power operating mode of high-power ASMF.

  2. Nickel recovery from electric arc furnace slag by magnetic separation

    Directory of Open Access Journals (Sweden)

    Sakaroglou Marianna


    Full Text Available During the pyrometallurgical treatment of the nickel-bearing laterite in the plant of G.M.M. S.A. LARCO, slag is produced after treatment in electric-arc furnace (EAF that contains 0.10 to 0.20 % Ni. Taking into account the great quantity of slag produced per year, the recovery of nickel from the EAF slag will add benefits to the entire process. The target of the current work is to investigate the possibility of nickel recovery from EAF slag by magnetic separation. To meet the target, the effect of the following parameters was studied: grain size, magnetic field intensity, thickness of slag layer, moisture content, and re-grinding of the coarser slag particles. The results show that it is possible to obtain a magnetic product with nickel grade close to that of the primary raw material or even better, with sufficient nickel recovery.

  3. Challenges in simulation of chemical processes in combustion furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M.; Kilpinen, P. [Aabo Akademi, Turku (Finland)


    The presentation gives an introduction to some of the present issues and problems in treating the complex chemical processes in combustion. The focus is in the coupling of the hydrocarbon combustion process with nitrogen oxide formation and destruction chemistry in practical furnaces or flames. Detailed kinetic modelling based on schemes of elementary reactions are shown to be a useful novel tool for identifying and studying the key reaction paths for nitrogen oxide formation and destruction in various systems. The great importance of the interaction between turbulent mixing and combustion chemistry is demonstrated by the sensitivity of both methane oxidation chemistry and fuel nitrogen conversion chemistry to the reactor and mixing pattern chosen for the kinetic calculations. The fluidized bed combustion (FBC) nitrogen chemistry involves several important heterogeneous reactions. Particularly the char in the bed plays an essential role. Recent research has advanced rapidly and the presentation proposes an overall picture of the fuel nitrogen reaction routes in circulating FBC conditions. (author)

  4. The Microgravity Science Glovebox (MSG), a Resource for Gravity-Dependent Phenomena Research on the International Space Station (ISS) (United States)

    Spivey, Reggie A.; Jeter, Linda B.; Vonk, Chris


    The Microgravity Science Glovebox (MSG) is a double rack facility aboard the International Space Station (ISS) designed for gravity-dependent phenomena investigation handling. The MSG has been operating in the ISS US Laboratory Module since July 2002. The MSG facility provides an enclosed working area for investigation manipulation and observation in the ISS. The MSG s unique design provides two levels of containment to protect the ISS crew from hazardous operations. Research investigations operating inside the MSG are provided a large 255 liter work volume, 1000 watts of dc power via a versatile supply interface (120,28, +/-12, and 5 Vdc), 1000 watts of cooling capability, video and data recording and real time downlink, ground commanding capabilities, access to ISS Vacuum Exhaust and Vacuum Resource Systems, and gaseous nitrogen supply. With these capabilities, the MSG is an ideal platform for research required to advance the technology readiness levels (TRL) needed for the Crew Exploration Vehicle and the Exploration Initiative. Areas of research that will benefit from investigations in the MSG include thermal management, fluid physics, spacecraft fire safety, materials science, combustion and reacting control systems, in situ fabrication and repair, and advanced life support technologies. This paper will provide a detailed explanation of the MSG facility, a synopsis of the research that has already been accomplished in the MSG, an overview of investigations planning to operate in the MSG, and possible augmentations that can be added to the MSG facility to further enhance the resources provided to investigations.

  5. 40 CFR 424.10 - Applicability; description of the open electric furnaces with wet air pollution control devices... (United States)


    ... electric furnaces with wet air pollution control devices subcategory. 424.10 Section 424.10 Protection of... MANUFACTURING POINT SOURCE CATEGORY Open Electric Furnaces With Wet Air Pollution Control Devices Subcategory § 424.10 Applicability; description of the open electric furnaces with wet air pollution control devices...

  6. Nodal wear model: corrosion in carbon blast furnace hearths

    Directory of Open Access Journals (Sweden)

    Verdeja, L. F.


    Full Text Available Criterions developed for the Nodal Wear Model (NWM were applied to estimate the shape of the corrosion profiles that a blast furnace hearth may acquire during its campaign. Taking into account design of the hearth, the boundary conditions, the characteristics of the refractory materials used and the operation conditions of the blast furnace, simulation of wear profiles with central well, mushroom and elephant foot shape were accomplished. The foundations of the NWM are constructed considering that the corrosion of the refractory is a function of the temperature present at each point (node of the liquid metal-refractory interface and the corresponding physical and chemical characteristics of the corrosive fluid.

    Se aplican los criterios del Modelo de Desgaste Nodal (MDN para la estimación de los perfiles de corrosión que podría ir adquiriendo el crisol de un homo alto durante su campaña. Atendiendo al propio diseño del crisol, a las condiciones límites de contorno, a las características del material refractario utilizado y a las condiciones de operación del horno, se consiguen simular perfiles de desgaste con "pozo central", con "forma de seta" ó de "pie de elefante". Los fundamentos del MDN se apoyan en la idea de considerar que la corrosión del refractario es función de la temperatura que el sistema pueda presentar en cada punto (nodo de la intercara refractario-fundido y de las correspondientes características físico-químicas del fluido corrosivo.


    Directory of Open Access Journals (Sweden)

    R.N. Khrestin


    Full Text Available Purpose. The aim is to build a mathematical model of the electric arc of arc furnace (EAF. The model should clearly show the relationship between the main parameters of the arc. These parameters determine the properties of the arc and the possibility of optimization of melting mode. Methodology. We have built a fairly simple model of the arc, which satisfies the above requirements. The model is designed for the analysis of electromagnetic processes arc of varying length. We have compared the results obtained when testing the model with the results obtained on actual furnaces. Results. During melting in real chipboard under the influence of changes in temperature changes its properties arc plasma. The proposed model takes into account these changes. Adjusting the length of the arc is the main way to regulate the mode of smelting chipboard. The arc length is controlled by the movement of the drive electrode. The model reflects the dynamic changes in the parameters of the arc when changing her length. We got the dynamic current-voltage characteristics (CVC of the arc for the different stages of melting. We got the arc voltage waveform and identified criteria by which possible identified stage of smelting. Originality. In contrast to the previously known models, this model clearly shows the relationship between the main parameters of the arc EAF: arc voltage Ud, amperage arc id and length arc d. Comparison of the simulation results and experimental data obtained from real particleboard showed the adequacy of the constructed model. It was found that character of change of magnitude Md, helps determine the stage of melting. Practical value. It turned out that the model can be used to simulate smelting in EAF any capacity. Thus, when designing the system of control mechanism for moving the electrode, the model takes into account changes in the parameters of the arc and it can significantly reduce electrode material consumption and energy consumption

  8. Slagging and Fouling Characteristics of HRSG for Ferrosilicon Electric Furnaces

    Directory of Open Access Journals (Sweden)

    Yungang Wang


    Full Text Available The slagging and fouling characteristics of the heat recovery steam generator (HRSG for ferrosilicon electric furnaces are discussed in this paper. Three ash samples were taken from the HRSG of a ferrosilicon furnace in Ningxia Province, China, which suffered from serious slagging and fouling. X-ray fluorescence (XRF, X-ray powder diffraction (XRD and scanning electron microscope (SEM were used to analyze the ash samples. The results show that low melting point salt Na2SO4 and composite salts Na (AlSi3O8 and 3K2SO4·CaSO4 deposit on the superheater tube walls in aerosol form and solidify to form the initial slag layer. With the continuous deposition of the low melting point compounds, more and more ash particles in the flue gas adhere to the slag surface to form a thicker slag. Low melting point composite salt NaO·Al2O3·SiO2 is absorbed on the evaporator tube walls in aerosol form. With the deposition of NaO·Al2O3·SiO2, more and more ash particles are absorbed to form the fouling. Since there is less space between pin-finned tubes, the large iron-rich slag particles are easily deposited on tube walls and fin surfaces, which is advantageous to the fouling process. There are large quantities of superfine ash particles in the flue gas that easily adhere to other particles or tube walls, which facilitates the slagging and fouling process.

  9. Vacuum maintenance in hermetically sealed MEMs packages (United States)

    Corazza, Alessio; Kullberg, Richard C.


    Packages for many high sensitivity MEM devices (Micro- Electro-Mechanical devices) such as accelerometers need to operate in a vacuum in order to obtain their full performance. This vacuum is destroyed by the outgassing of species such as hydrogen and water vapor from the surfaces of the package exposed to this vacuum. To control this outgassing a getter is needed. MEM packages are too small to accommodate traditional sintered porous getters. A solution has been developed using a high porosity thick film getter material. The getter consists of a highly porous, mechanically stable, getter coating on a metal substrate. This getter reacts with active gases such as water vapor, hydrogen, oxygen, nitrogen, and carbon monoxide that outgas from the inner surfaces of the package. The physical characteristics and performance of this material will be demonstrated per ASTM sorption testing. The results of this testing will be used to demonstrate the potential for vacuum performance in a real world MEM package.

  10. Vapor-barrier Vacuum Isolation System (United States)

    Weinstein, Leonard M. (Inventor); Taminger, Karen M. (Inventor)


    A system includes a collimated beam source within a vacuum chamber, a condensable barrier gas, cooling material, a pump, and isolation chambers cooled by the cooling material to condense the barrier gas. Pressure levels of each isolation chamber are substantially greater than in the vacuum chamber. Coaxially-aligned orifices connect a working chamber, the isolation chambers, and the vacuum chamber. The pump evacuates uncondensed barrier gas. The barrier gas blocks entry of atmospheric vapor from the working chamber into the isolation chambers, and undergoes supersonic flow expansion upon entering each isolation chamber. A method includes connecting the isolation chambers to the vacuum chamber, directing vapor to a boundary with the working chamber, and supersonically expanding the vapor as it enters the isolation chambers via the orifices. The vapor condenses in each isolation chamber using the cooling material, and uncondensed vapor is pumped out of the isolation chambers via the pump.

  11. LCLS XTOD Tunnel Vacuum System (XVTS)

    Energy Technology Data Exchange (ETDEWEB)

    Beale, R; Duffy, P; Kishiyama, K; Mckernan, M; McMahon, D; Lewis, S; Trent, J; Tung, L; Shen, S


    The vacuum system of the XVTS (X-Ray Vacuum Transport System) for the LCLS (Linac Coherent Light Source) XTOD (X-ray Transport, Optics and Diagnostics) system has been analyzed and configured by the Lawrence Livermore National Laboratory's NTED (New Technologies Engineering Division) as requested by the SLAC/LCLS program. The system layout, detailed analyses and selection of the vacuum components for the XTOD tunnel section are presented in this preliminary design report. The vacuum system was analyzed and optimized using a coupled gas load balance model of sub-volumes of the components to be evacuated. Also included are the plans for procurement, mechanical integration, and the cost estimates.

  12. Thermal conductance measurement on vacuum glazing

    Energy Technology Data Exchange (ETDEWEB)

    Ng, N.; Collins, R.E.; So, L. [School of Physics, University of Sydney, A28, NSW 2006 (Australia)


    A method is described for measuring the thermal conductance of vacuum glazing that is well-suited for integration into the manufacturing process of such devices. The sample of vacuum glazing to be measured, initially at elevated temperature, is placed in contact with a second sample of vacuum glazing with a known thermal conductance. The external surfaces of the glazings are then cooled by forced flow of air at room temperature, and a measurement is made of the rate of decrease of the temperature of the contacting glass sheets of the two samples. The method is simple to implement, and can be automated. The results obtained with the method are quite reproducible. The measurement can be made as the production samples of vacuum glazing cool at the completion of the manufacturing process, resulting in significant savings in time and labour compared with other methods. (author)

  13. Production of Lunar Oxygen Through Vacuum Pyrolysis

    National Research Council Canada - National Science Library

    Matchett, John


    .... The vacuum pyrolysis method of oxygen production from lunar regolith presents a viable option for in situ propellant production because of its simple operation involving limited resources from earth...

  14. Cold vacuum drying facility design requirements

    Energy Technology Data Exchange (ETDEWEB)

    Irwin, J.J.


    This release of the Design Requirements Document is a complete restructuring and rewrite to the document previously prepared and released for project W-441 to record the design basis for the design of the Cold Vacuum Drying Facility.

  15. Postural orientation in microgravity depends on straightening up movement performed (United States)

    Vaugoyeau, Marianne; Assaiante, Christine


    Whether the vertical body orientation depends on the initial posture and/or the type of straightening up movement is the main question raised in this paper. Another objective was to specify the compensatory role of visual input while adopting an erected posture during microgravity. The final body orientation was analysed in microgravity during parabolic flights. After either (1) straightening up movement from a crouching or (2) a sitting posture, with and without vision. The main results are the following: (1) a vertical erected final posture is correctly achieved after sit to stand movement, whereas all subjects were tilted forward after straightening up from a crouching posture and (2) vision may contribute to correct final posture. These results suggest the existence of a re-weighting of the remaining sensory information, visual information, contact cutaneous cues and proprioceptive information under microgravity condition. We can put forward the alternative hypothesis that the control of body orientation under microgravity condition may also be achieved on the basis of a postural body scheme, that seems to be dependant on the type of movement and/ or the initial position of the whole body.

  16. Orbital and Intracranial Effects of Microgravity: 3T MRI Findings (United States)

    Kramer, L. A.; Sargsyan, A.; Hasan, K. M.; Polk, J. D.; Hamilton, D. R.


    Goals and Objectives of this presentation are: 1. To briefly describe a newly discovered clinical entity related to space flight. 2. To describe normal anatomy and pathologic changes of the optic nerve, posterior globe, optic nerve sheath and pituitary gland related to exposure to microgravity. 3. To correlate imaging findings with known signs of intracranial hypertension.

  17. FY 1994 annual report. Advanced combustion science utilizing microgravity

    Energy Technology Data Exchange (ETDEWEB)



    Researches on combustion in microgravity were conducted to develop combustion devices for advanced combustion techniques, and thereby to cope with the requirements for diversification of energy sources and abatement of environmental pollution by exhaust gases. This project was implemented under the research cooperation agreement with US's NASA, and the Japanese experts visited NASA's test facilities. NASA's Lewis Research Center has drop test facilities, of which the 2.2-sec drop test facilities are useful for researches by Japan. The cooperative research themes for combustion in microgravity selected include interactions between fuel droplets, high-pressure combustion of binary fuel sprays, and ignition and subsequent flame propagation in microgravity. An ignition test equipment, density field measurement equipment and flame propagation test equipment were constructed in Japan to conduct the combustion tests in microgravity for, e.g., combustion and evaporation of fuel droplets, combustion characteristics of liquid fuels mixed with solid particles, combustion of coal/oil mixture droplets, and estimating flammability limits. (NEDO)


    NARCIS (Netherlands)


    Under microgravity conditions in both parabolic and sounding rocket flights, the mass-transfer-induced Marangoni convection around an air bubble was studied. To prevent the bubble from becoming saturated, the bubble was ventilated. It turned out that the flow rate of the air through the bubble

  19. Micro-gravity Isolation using only Electro-magnetic Actuators

    DEFF Research Database (Denmark)

    Vinther, D.; Alminde, Lars; Bisgaard, Morten

    In this paper the design, construction and test of a free floating micro-gravity isolation platform to reduce the acceleration dose on zero gravity experiments on e.g. the International Space Station (ISS) is discussed. During the project a system is specified and constructed whereupon it is tested...

  20. Micro-gravity Isolation using only Electro-magnetic Actuators

    DEFF Research Database (Denmark)

    Vinther, D.; Alminde, Lars; Bisgaard, Morten


    In this paper the design, construction and test of a free floating micro-gravity isolation platform to reduce the acceleration dose on zero gravity experiments on e.g. the International Space Station (ISS) is discussed. During the project a system is specified and constructed whereupon it is test...