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Sample records for injection ceramic chambers

  1. METALLIZATION OF CERAMIC VACUUM CHAMBERS FOR SNS RING INJECTION KICKER MAGNETS.

    Energy Technology Data Exchange (ETDEWEB)

    HE,P.; HSEUH,H.C.; TODD,R.J.

    2002-04-22

    Ceramic chambers will be used in the pulsed kicker magnets for the injection of H{sup -} into the US Spallation Neutron Source (SNS) accumulator ring. There are two reasons for using ceramic chambers in kickers: (1) to avoid shielding of a fast-changing external magnetic field by metallic chamber walls; and (2) to reduce heating due to eddy currents. The inner surfaces of the ceramic chambers will be coated with a conductive layer, possibly titanium (Ti) or copper with a titanium nitride (TiN) overlayer, to reduce the beam coupling impedance and provide passage for beam image current. This paper describes the development of sputtering method for the 0.83m long 16cm inner diameter ceramic chambers. Coatings of Ti, Cu and TiN with thicknesses up to 10 {micro}m were produced by means of DC magnetron sputtering. The difficulty of coating insulators was overcome with the introduction of an anode screen. Films with good adhesion, uniform longitudinal thickness, and conductivity were produced.

  2. Physical and Electromagnetic Properties of Customized Coatings for SNS Injection Ceramic Chambers and Extraction Ferrite Kickers

    CERN Document Server

    Hseuh Hsiao Chaun; He, Ping; Henderson, Stuart; Pai, Chien; Raparia, Deepak; Todd, Robert J; Wang, Lanfa; Wei, Jie; Weiss, Daniel; Yung Lee, Yong

    2005-01-01

    The inner surfaces of the 248 m SNS accumulator ring vacuum chambers are coated with ~100 nm of titanium nitride (TiN) to reduce the secondary electron yield (SEY) of the chamber walls. All the ring inner surfaces are made of stainless or inconel, except those of the injection and extraction kickers. Ceramic vacuum chambers are used for the 8 injection kickers to avoid shielding of a fast-changing kicker field and to reduce eddy current heating. The internal diameter was coated with Cu to reduce the beam coupling impedance and provide passage for beam image current, and a TiN overlayer to reduce SEY. The ferrite surfaces of the 14 extraction kicker modules were coated with TiN to reduce SEY. Customized masks were used to produce coating strips of 1 cm x 5 cm with 1 to 1.5 mm separation among the strips. The masks maximized the coated area to more than 80%, while minimizing the eddy current effect to the kicker rise time. The coating method, as well as the physical and electromagnetic properties of the coating...

  3. The APS ceramic chambers

    Energy Technology Data Exchange (ETDEWEB)

    Milton, S.; Warner, D.

    1994-07-01

    Ceramics chambers are used in the Advanced Photon Source (APS) machines at the locations of the pulsed kicker and bumper magnets. The ceramic will be coated internally with a resistive paste. The resistance is chosen to allow the low frequency pulsed magnet field to penetrate but not the high frequency components of the circulating beam. Another design goal was to keep the power density experienced by the resistive coating to a minimum. These ceramics, their associated hardware, the coating process, and our recent experiences with them are described.

  4. Using a ceramic chamber in kicker magnets

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S.

    1993-05-01

    A ceramic chamber inside kicker magnets can provide the relevant field risetime. On the other hand, some metallic coating inside has to prevent static charge buildup and shield the beam from ceramic and ferrite at high frequencies to avoid possible resonances. The issues concerning the metallized ceramic chamber, such as coupling impedances and requirements on the coating, are studied to find a compromise solution for kickers of the Medium Energy Booster at the Superconducting Super Collider.

  5. In situ measurement of ceramic vacuum chamber conductive coating quality

    Energy Technology Data Exchange (ETDEWEB)

    Doose, C.; Harkay, K.; Kim, S.; Milton, S.

    1997-08-01

    A method for measuring the relative surface resistivity and quality of conductive coatings on ceramic vacuum chambers was developed. This method is unique in that it allows one to test the coating even after the ceramic chamber is installed in the accelerator and under vacuum; furthermore, the measurement provides a localized surface reading of the coating conductance. The method uses a magnetic probe is calibrated using the measured DC end-to-end resistance of the tube under test and by comparison to a high quality test surface. The measurement method has also been verified by comparison to high frequency impedance measurements. A detailed description, results, and sensitivity of the technique are given here.

  6. Ceramic resistive plate chambers for high rate environments

    Energy Technology Data Exchange (ETDEWEB)

    Laso Garcia, Alejandro; Kaempfer, Burkhard; Kaspar, Markus; Kotte, Roland; Peschke, Richard; Stach, Daniel; Wendisch, Christian; Wuestenfeld, Joern [Helmholtz Zentrum, Dresden-Rossendorf (Germany); Collaboration: CBM-Collaboration

    2012-07-01

    Multi-gap resistive plate chambers will be used to build the time of flight wall of the compressed baryonic matter experiment (CBM) at FAIR with a time resolution better than 80 ps. The high fluxes expected at the innermost part of the detector, 20 x 10{sup 3} cm{sup -2}s{sup -1} have made necessary the development of new materials capable of withstanding such fluxes. At Helmholtz Zentrum Dresden-Rossendorf, several RPC prototypes of 10 x 10 cm{sup 2} and 20 x 20 cm{sup 2} have been built with ceramic plates with bulk resistivities in the range of 10{sup 9}-10{sup 10} Ohm cm. They have been tested at the superconducting electron accelerator facility ELBE with 30 MeV electrons and at COSY, Juelich, with 2.7 Gev/c protons. We present characteristics of the ceramic electrodes and the latest results concerning the performance of these prototypes in electron and proton beams up to fluxes of 10{sup 6} cm{sup -2}s{sup -1}.

  7. Ceramic resistive plate chambers for high rate environments

    Energy Technology Data Exchange (ETDEWEB)

    Laso Garcia, Alejandro; Kaspar, Marcus; Kaempfer, Burkhard; Kotte, Roland; Naumann, Lothar; Stach, Daniel; Wendisch, Christian; Wuestenfeld, Joern [Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Sachsen (Germany); Collaboration: CBM-Collaboration

    2013-07-01

    The future Compressed Baryonic Matter Experiment to be built at FAIR is foreseen to use Resistive Plate Chambers as Time of Flight detectors. However, for the most central part of the ToF Wall high particle fluxes are expected, the simulations predict fluxes in the order of 2.10{sup 4} particles/cm{sup 2} s and even higher the closer the wall approaches the beampipe. This high fluxes show the need to develop new materials. At Helmholtz-Zentrum Dresden Rossendorf, new semiconductor ceramic composites have been developed, several prototypes of RPCs with ceramic electrodes up to 20 x 20 cm{sup 2} have been developed and tested. In this talk, the performance of this detectors in electron (ELBE) and proton (COSY) beams is presented, as well as, the performance of this detectors under irradiation in Ni+Pb collisions at 1.9 AGeV (SIS18, GSI). This performance can be quantified as an efficiency close to 100% and a time resolution better than 100 ps.

  8. Ducted combustion chamber for direct injection engines and method

    Science.gov (United States)

    Mueller, Charles

    2015-03-03

    An internal combustion engine includes an engine block having a cylinder bore and a cylinder head having a flame deck surface disposed at one end of the cylinder bore. A piston connected to a rotatable crankshaft and configured to reciprocate within the cylinder bore has a piston crown portion facing the flame deck surface such that a combustion chamber is defined within the cylinder bore and between the piston crown and the flame deck surface. A fuel injector having a nozzle tip disposed in fluid communication with the combustion chamber has at least one nozzle opening configured to inject a fuel jet into the combustion chamber along a fuel jet centerline. At least one duct defined in the combustion chamber between the piston crown and the flame deck surface has a generally rectangular cross section and extends in a radial direction relative to the cylinder bore substantially along the fuel jet centerline.

  9. Radiation-hard ceramic Resistive Plate Chambers for forward TOF and T0 systems

    Science.gov (United States)

    Akindinov, A.; Dreyer, J.; Fan, X.; Kämpfer, B.; Kiselev, S.; Kotte, R.; Garcia, A. Laso; Malkevich, D.; Naumann, L.; Nedosekin, A.; Plotnikov, V.; Stach, D.; Sultanov, R.; Voloshin, K.

    2017-02-01

    Resistive Plate Chambers with ceramic electrodes are the main candidates for a use in precise multi-channel timing systems operating in high-radiation conditions. We report the latest R&D results on these detectors aimed to meet the requirements of the forward T0 counter at the CBM experiment. RPC design, gas mixture, limits on the bulk resistivity of ceramic electrodes, efficiency, time resolution, counting rate capabilities and ageing test results are presented.

  10. Sintering products molded by injecting ceramic and metal powders

    Institute of Scientific and Technical Information of China (English)

    LIU Ping-an; ZENG Ling-ke; LI Xiu-yan

    2005-01-01

    The injection molding products with different volume ratios of ZrO2 ceramic powder to 316L stainless steel powder were prepared. Properties and structure of the products were characterized by X-ray diffraction(XRD),scanning electron microscope(SEM) and transmission electron microscope (TEM). The results show that the compressive stress exists in the products and the bend strength reaches 300 MPa. ZrO2 phase and stainless steel phase are uniform in samples. The toughness of ceramic increases with the increasing the content of stainless steel.Through TEM study of the interface, some crystalline orientation relationships are determined.

  11. Potential Applications of the Ceramic Thrust Chamber Technology for Future Transpiration Cooled Rocket Engines

    Science.gov (United States)

    Herbertz, Armin; Ortelt, Markus; Müller, Ilja; Hald, Hermann

    The long-term development of ceramic rocket engine thrust chambers at the German Aerospace Center(DLR) currently leads to designs of self-sustaining, transpiration-cooled, fiber-reinforced ceramic rocket engine chamber structures.This paper discusses characteristic issues and potential benefits introduced by this technology. Achievable benefits are the reduction of weight and manufacturing cost, as well as an increased reliability and higher lifetime due to thermal cycle stability.Experiments with porous Ceramic Matrix Composite(CMC) materials for rocket engine chamber walls have been conducted at the DLR since the end of the 1990s.This paper discusses the current status of DLR's ceramic thrust chamber technology and potential applications for high thrust engines.The manufacturing process and the design concept are explained.The impact of variations of engine parameters(chamber pressure and diam-eter)on the required coolant mass flow are discussed.Due to favorable scaling effects a high thrust application utilizes all benefits of the discussed technology, while avoiding the most significant performance drawbacks.

  12. Experimental Evaluation of the RF Shielding Properties of a Thin Resistive Layer in a Ceramic Chamber

    CERN Document Server

    Brandt, D; Mostacci, A; Rinolfi, Louis; Ruggiero, F; Tsutsui, H; Vos, L

    2000-01-01

    In order to better understand the RF shielding properties of a thin resistive layer inside a ceramic vacuum chamber, an experimental set-up has been installed in the Electron Positron Accumulator (EPA) at CERN. A 500 MeV single bunch of about 7 x 1010 electrons (rms s=1 ns) is extracted into this dedicated beam line at a repetition rate of about 1 Hz. Wideband magnetic field probes are installed on the outer surfaces of a resistively coated ceramic test chamber as well as on a reference non-coated chamber located 2.5 m downstream the line. At the end of the extraction line, the beam passes through a thin Aluminum foil and is absorbed in an external dump. The experimental layout and the first results are presented. A comparison with theoretical expectations as well as possible implications for future machines are also discussed.

  13. Development and evaluation of magnesium oxide-based ceramics for chamber parts in mass-production plasma etching equipment

    Science.gov (United States)

    Kasashima, Yuji; Tsutsumi, Kota; Mitomi, Shinzo; Uesugi, Fumihiko

    2017-06-01

    In mass-production plasma etching equipment, the corrosion of ceramic chamber parts reduces the production yield of LSI and overall equipment effectiveness (OEE) owing to contamination, short useful life, and particle generation. Novel ceramics that can improve the production yield and OEE are highly required. We develop magnesium oxide (MgO)-based ceramics and evaluate them under mass-production plasma etching conditions. The results of this study indicate that the developed MgO-based ceramics with high mechanical properties and low electric resistivity have a higher resistance to corrosion in plasma etching using CF4 gas than Si and conventional ceramic materials such as aluminum oxide and yttrium oxide.

  14. All- Ceramic Crown Preparation and the Remained wall Thickness of the Pulp Chamber

    Directory of Open Access Journals (Sweden)

    Mohammadzadeh Akhlaghi N.

    2012-12-01

    Full Text Available tatement of Problem: A minimally invasive method of preparation is essential to prevent tooth structure weakening and pulp irritation; especially for mandibular anterior single-tooth all-ceramic crowns. According to many investigations, one of the most important reasons of pulp injury caused by tooth preparation for different restorative procedures is reduced “remained wall thickness” (RWT. In order to protect the pulp from irritation, it is necessary to maintain a 0.5 mm of RWT.Purpose: The purpose of the present study was to evaluate the effect of all-ceramic crown preparation on pulp chamber RWT of mandibular incisors.Materials and Method: Mesiodistal and buccolingual initial images of 24 ex-tracted mandibular incisors were provided. The pulp chamber initial wall thick-nesses of buccal, lingual and proximal surfaces of cervical, 1and 2 mm above the cervical areas and also the incisal surfaces of incisal sections were measured using digital radiography and Photoshop software. After all-ceramic crown preparation, images were provided at the same initial positions. The initial and remained pulp chamber wall thicknesses were statistically evaluated and analyzed by ANOVA, paired t-test and a post hoc Tukey test.Results: Repeated measures ANOVA showed that the mean of pre- or post-preparation wall thicknesses were not significantly different for each surface at the three horizontal levels (p> 0.05. However, there were significant differences between the surfaces for each section. Comparison of pre- and post-preparation wall thicknesses revealed significant differences (p< 0.05. Proximal surfaces of cervical sections had the least RWT (0.42±0.12.Conclusion: According to the results of the present study, the least amount of initial and remained wall thicknesses of pulp chamber were related to the proximal surfaces, particularly in cervical areas. Therefore a reduction of preparation to 0.7 mm is suggested to prevent future pulp injury for

  15. The effect of injection pressure and fuel viscosity on the spray characteristics of biodiesel blends injected into an atmospheric chamber

    Energy Technology Data Exchange (ETDEWEB)

    Ghurri, Ainul; Kim, Jae Duk; Kim, Hyung Gon; Jung, Jae Youn; Song, Kyu Keun [Chonbuk National Univ., Deokjin Gu (Korea, Republic of)

    2012-09-15

    An experimental study was conducted to examine the effect of injection pressure and fuel type on the spray tip penetration length and the angle of spray injected into atmospheric chamber. The objective of the present study is to formulate empirical correlations of the spray tip penetration and the spray angle for non evaporative condition. The experiment was performed by a common rail type high pressure injector for the diesel engine at the injection pressure 40{approx}100 MPa and four different fuels (D100, BD25, BD45, and BD65). The results showed that the biodiesel content increased the spray tip penetration and decreased the spray angle. The correlation of spray tip penetration is expressed for each region before and after spray break up time in terms of injection pressure, fuel viscosity and time after start of injection. The correlation is also obtained for spray angle equation terms of injection pressure and fuel viscosity.

  16. Experimental Investigation of Comparative Process Capabilities of Metal and Ceramic Injection Molding for Precision Applications

    DEFF Research Database (Denmark)

    Islam, Aminul; Giannekas, Nikolaos; Marhöfer, David Maximilian;

    2016-01-01

    The purpose of this paper is to make a comparative study on the process capabilities of the two branches of the powder injection molding (PIM) process—metal injection molding (MIM) and ceramic injection molding (CIM), for high-end precision applications. The state-of-the-art literature does not m...

  17. Injection of Nucleate-Boiling Slug Flows into a Heat Exchange Chamber in Microgravity

    Science.gov (United States)

    2015-06-01

    AFRL-AFOSR-UK-TR-2015-0029 Injection of nucleate- boiling slug flows into a heat exchange chamber in microgravity Jaume...2015 2. REPORT TYPE Final Report 3. DATES COVERED (From – To) 20 March 2012 – 19 March 2015 4. TITLE AND SUBTITLE Injection of nucleate- boiling ...method to produce controlled boiling through a localized nucleation cavity feeding a capillary crossflow forming regular trains of bubbles. The main

  18. Modeling injection molding of net-shape active ceramic components.

    Energy Technology Data Exchange (ETDEWEB)

    Baer, Tomas (Gram Inc.); Cote, Raymond O.; Grillet, Anne Mary; Yang, Pin; Hopkins, Matthew Morgan; Noble, David R.; Notz, Patrick K.; Rao, Rekha Ranjana; Halbleib, Laura L.; Castaneda, Jaime N.; Burns, George Robert; Mondy, Lisa Ann; Brooks, Carlton, F.

    2006-11-01

    To reduce costs and hazardous wastes associated with the production of lead-based active ceramic components, an injection molding process is being investigated to replace the current machining process. Here, lead zirconate titanate (PZT) ceramic particles are suspended in a thermoplastic resin and are injected into a mold and allowed to cool. The part is then bisque fired and sintered to complete the densification process. To help design this new process we use a finite element model to describe the injection molding of the ceramic paste. Flow solutions are obtained using a coupled, finite-element based, Newton-Raphson numerical method based on the GOMA/ARIA suite of Sandia flow solvers. The evolution of the free surface is solved with an advanced level set algorithm. This approach incorporates novel methods for representing surface tension and wetting forces that affect the evolution of the free surface. Thermal, rheological, and wetting properties of the PZT paste are measured for use as input to the model. The viscosity of the PZT is highly dependent both on temperature and shear rate. One challenge in modeling the injection process is coming up with appropriate constitutive equations that capture relevant phenomenology without being too computationally complex. For this reason we model the material as a Carreau fluid and a WLF temperature dependence. Two-dimensional (2D) modeling is performed to explore the effects of the shear in isothermal conditions. Results indicate that very low viscosity regions exist near walls and that these results look similar in terms of meniscus shape and fill times to a simple Newtonian constitutive equation at the shear-thinned viscosity for the paste. These results allow us to pick a representative viscosity to use in fully three-dimensional (3D) simulation, which because of numerical complexities are restricted to using a Newtonian constitutive equation. Further 2D modeling at nonisothermal conditions shows that the choice of

  19. Demonstrating the self-healing behaviour of some selected ceramics under combustion chamber conditions

    Science.gov (United States)

    Farle, A.; Boatemaa, L.; Shen, L.; Gövert, S.; Kok, J. B. W.; Bosch, M.; Yoshioka, S.; van der Zwaag, S.; Sloof, W. G.

    2016-08-01

    Closure of surface cracks by self-healing of conventional and MAX phase ceramics under realistic turbulent combustion chamber conditions is presented. Three ceramics namely; Al2O3, Ti2AlC and Cr2AlC are investigated. Healing was achieved in Al2O3 by even dispersion of TiC particles throughout the matrix as the MAX phases, Ti2AlC and Cr2AlC exhibit intrinsic self-healing. Fully dense samples (>95%) were sintered by spark plasma sintering and damage was introduced by indentation, quenching and low perpendicular velocity impact methods. The samples were exposed to the oxidizing atmosphere in the post flame zone of a turbulent flame in a combustion chamber to heal at temperatures of approx. 1000 °C at low pO2 levels for 4 h. Full crack-gap closure was observed for cracks up to 20 mm in length and more than 10 μm in width. The reaction products (healing agents) were analysed by scanning electron microscope, x-ray microanalysis and XRD. A semi-quantification of the healing showed that cracks in Al2O3/TiC composite (width 1 μm and length 100 μm) were fully filled with TiO2. In Ti2AlC large cracks were fully filled with a mixture of TiO2 and Al2O3. And in the Cr2AlC, cracks of up to 1.0 μm in width and more than 100 μm in length were also completely filled with Al2O3.

  20. Studies on a diesel engine with ceramic coating of the combustion chamber

    Energy Technology Data Exchange (ETDEWEB)

    Jaskolski, J.

    1985-06-01

    Two piston alloys were developed which were combined with ceramic fibres made of aluminium silicone oxide. These alloys have proved to be wear resistant and resistant to thermal stresses. A simulation stand was used to study the influence of these cylinder head coatings, which are applied by plasma spraying, on the thermal status of the piston, and the influence of the thermic insulation of the sections of the combustion chamber was studied on an engine test stand. The ceramic coating was 0.2 mm thick; the temperature drops in the fire land and in the piston ring groove were 40 K and 20 K respectively. The thermically insulated piston head meant that the combustion of the mixture took less time, altered the fuel consumption, raised the exhaust temperature and reduced exhaust toxicity and the amount of air sucked in. The heat given off with the coolant was reduced by 5 to 15%. The overall finding was that raising the temperature and hence the exhaust energy creates favourable conditions for the application of turbo-charging, thereby improving overall performance.

  1. Challenges Surrounding the Injection and Arrival of Targets at LIFE Fusion Chamber Center

    Energy Technology Data Exchange (ETDEWEB)

    Miles, R; Spaeth, M; Manes, K; Amendt, P; Tabak, M; Bond, T; Kucheyev, S; Latkowski, J; Loosmore, G; Bliss, E; Baker, K; Bhandarkar, S; Petzoldt, R; Alexander, N; Tillack, M; Holdener, D

    2010-12-01

    IFE target designers must consider several engineering requirements in addition to the physics requirements for successful target implosion. These considerations include low target cost, high manufacturing throughput, the ability of the target to survive the injection into the fusion chamber and arrive in a condition and physical position consistent with proper laser-target interaction and ease of post-implosion debris removal. This article briefly describes these considerations for the Laser Inertial Fusion-based Energy (LIFE) targets currently being designed.

  2. Ceramic particle injection during laser treatment of Titanium

    NARCIS (Netherlands)

    Kloosterman, A.J.; de Hosson, J.T.M.; Aliabadi, MH; Brebbia, CA

    1997-01-01

    This paper concentrates on the laser particle injection process. Slight changes in the conditions of injection process, substantially influence the microstructure of the modified layer. TiC, TiN and SiC particles were injected into Ti-6Al-4V, which resulted in the formation of a metal matrix composi

  3. Ceramic particle injection during laser treatment of Titanium

    NARCIS (Netherlands)

    Kloosterman, A.J.; de Hosson, J.T.M.; Aliabadi, MH; Brebbia, CA

    1997-01-01

    This paper concentrates on the laser particle injection process. Slight changes in the conditions of injection process, substantially influence the microstructure of the modified layer. TiC, TiN and SiC particles were injected into Ti-6Al-4V, which resulted in the formation of a metal matrix

  4. METAL-CERAMIC INTERFACES PRODUCED BY LASER MELT INJECTION PROCESSING

    NARCIS (Netherlands)

    DEHOSSON, JTM; VANDENBURG, M; Burg, M. van den

    1995-01-01

    This paper concentrates on the mechanical performance of various ceramic coatings of Cr2O3 on steel (SAF2205), as produced by CO2 laser processing. It is concluded that a firmly bonded coating of Cr2O3 on steel could be produced by high power laser processing. The actual interface strength of a

  5. METAL-CERAMIC INTERFACES PRODUCED BY LASER MELT INJECTION PROCESSING

    NARCIS (Netherlands)

    DEHOSSON, JTM; VANDENBURG, M; Burg, M. van den

    1995-01-01

    This paper concentrates on the mechanical performance of various ceramic coatings of Cr2O3 on steel (SAF2205), as produced by CO2 laser processing. It is concluded that a firmly bonded coating of Cr2O3 on steel could be produced by high power laser processing. The actual interface strength of a (Fe,

  6. Micro powder-injection moulding of metals and ceramics

    Indian Academy of Sciences (India)

    Volker Piotter; Thomas Gietzelt; Lothar Merz

    2003-02-01

    Development of micro-MIM/-CIM was started at Forschungszentrum Karlsruhe with the aim of creating a process suitable for a wide range of materials as well as for medium-scale and large-scale production of micro components. Using enhanced machine technology and special tempering procedures, this process enables the manufacturing of metal and ceramic devices with smallest wall thicknesses of 50 m and structural details of less than 3 m. Using ultra-fine ceramic powders (e.g. zirconia) and high-quality LIGA mould inserts, surface qualities of $R_a =$ 40 nm or $R_{\\text{max}} \\leq$ 3 mm could be obtained. Possible practical applications are demonstrated by components of micro-annular gear pumps made of zirconia for future handling of very small volumes of dangerous fluids and micro samples (tensile and bending specimens) suitable for mechanical testing of metals (316L, 17-4PH) and ceramic materials (Al23, ZrO2) in the micrometre range.

  7. Laser melt injection of ceramic particles in metals : Processing, microstructure and properties

    NARCIS (Netherlands)

    Ocelík, V.; De Hosson, J.Th.M.

    2010-01-01

    The objective of this paper is to present an overview of the possibilities of the laser melt injection (LMI) methodology to enhance the surface of light-weighted metals by adding hard ceramic particles in the top layer, with the aim to enhance the wear resistance and to increase the hardness. In par

  8. Coatings with laser melt injection of ceramic particles

    NARCIS (Netherlands)

    de Hosson, J.T.M.; Ocelik, V.; de Oliveira, U.; Seal, S; Dahotre, NB; Moore, JJ; Suryanarayana, C; Agarwal, A

    2003-01-01

    The conditions for a successful Laser Melt Injection (LMI) of SiC and WC particles into the melt pool of Al8Si and Ti6Al4V alloys were studied experimentally and theoretically by FEM calculations. The laser employed is a high power Nd:YAG The formation of a relatively thick aluminium oxide layer on

  9. Pressureless sintering behavior of injection molded alumina ceramics

    Directory of Open Access Journals (Sweden)

    Liu W.

    2014-01-01

    Full Text Available The pressureless sintering behaviors of two widely used submicron alumina (MgOdoped and undoped with different solid loadings produced by injection molding have been studied systematically. Regardless of the sinterability of different powders depending on their inherent properties, solid loading plays a critical role on the sintering behavior of injection molded alumina, which greatly determines the densification and grain size, and leads to its full densification at low temperatures. As compared to the MgO-doped alumina powder, the undoped specimens exhibit a higher sinterability for its smaller particle size and larger surface area. While full densification could be achieved for MgO-doped powders with only a lower solid loading, due to the fact that MgO addition can reduce the detrimental effect of the large pore space on the pore-boundary separation.

  10. Significance of chamber pressure to complex multi-phase physics in jet engine fuel injection processes

    Science.gov (United States)

    Dahms, Rainer; Oefelein, Joseph

    2014-11-01

    Injection processes in jet engines at chamber pressures in excess of the thermodynamic critical pressure of the liquid fuel are not well understood. Under some conditions, a distinct two-phase interface may not exist anymore which eliminates the presence of classical spray atomization phenomena. A comprehensive model for jet engine fuel injections is derived to quantify the conditions under which the interfacial dynamics transition to diffusion-dominated mixing processes without surface tension. At certain conditions, the model shows two-phase interfaces with substantially increased thicknesses and distinctively reduced mean free paths in comparison to ambient pressure conditions. Then, the underlying assumptions of a distinct two-phase interface do not apply anymore and the interface along with its surface tension is shown to deteriorate as it broadens substantially. As a consequence of this physical complexity, the conceptual view of spray atomization and evaporation as an appropriate model for jet engine injection processes is, contrary to conventional wisdom, questionable at certain operating conditions. Instead, a Large Eddy Simulation using a dense-fluid approximation is applied which takes the complex thermo-physics of real-fluid behavior into account.

  11. A comparative study of metal and ceramic injection moulding for precision applications

    DEFF Research Database (Denmark)

    Islam, Aminul; Giannekas, Nikolaos; Marhöfer, David Maximilian

    2015-01-01

    . The two branches of PIM - metal injection moulding (MIM) and ceramic injection moulding (CIM) have been developed in parallel. Both processes are in a stage now where they can offer exciting possibilities for mass production of extremely precise and complex net shape products. For some applications, PIM...... process presents a dilemma for choosing between MIM and CIMas both the material classes can offer specific advantages and the process steps are identical. So a comparative study about the process capabilities between CIM and MIM will be useful for thorough understanding of the processes and to select...

  12. Closed chamber pupilloplasty with an injectable shape memory alloy clip in enucleated porcine eyes in the laboratory setting.

    Science.gov (United States)

    Erlanger, Michael S; Olson, Jeffrey L

    2012-01-01

    A novel surgical technique and novel surgical instrumentation for closing a pupil defect in a closed chamber eye is described. The technique was performed in a laboratory setting using ex-vivo porcine eyes using a 30-gauge deployment system to repair iris defects. Given the difficulty of suturing in a closed chamber eye, the use of an injectable, shape memory alloy clip offers the advantages of rapid, easy deployment and increased strength over conventional suture techniques.

  13. Flow structure of conical distributed multiple gas jets injected into a water chamber

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Jiajun; Yu, Yonggang [Nanjing University of Science and Technology, Nanjing (China)

    2017-04-15

    Based on an underwater gun firing project, a mock bullet with several holes on the head was designed and experimented to observe the combustion gas injected into a cylindrical water chamber through this mock bullet. The combustion gas jets contain one vertical central jet and 4 to 8 slant lateral jets. A high speed camera system was used to record the expansion of gas jets in the experimental study. In numerical simulations, the Euler two-fluid model and volume of fluid method were adopted to describe the gas-liquid flow. The results show the backflow zone in lateral jet is the main factor influencing the gas-liquid turbulent mixing in downstream. On cross sections, the gas volume fraction increased with time but the growth rate decreased. With a change of nozzle structure, the gas fraction was more affected than the shock structure.

  14. Aphakia Correction by Injection of Foldable Intra Ocular Lens in The Anterior Chamber

    Science.gov (United States)

    Giles, Kagmeni; Ernest, Moukouri; Christelle, Domngang; Georges, Nguefack-Tsague; Raoul, Cheuteu; Come, Ebana Mvogo; Wiedemann, Peter

    2013-01-01

    We assessed the outcomes of the use of anterior chamber foldable lens for unilateral aphakia correction at the University Teaching Hospital of Yaounde. In this retrospective, non-comparative, consecutive case series study, we reviewed the records of patients who underwent an operation for aphakia correction by the means of injection of an angular supported foldable lens between January 2009 and December 2011 in the University Teaching Hospital Yaounde. Student’s paired t-test was carried out to compare pre-operative and post-operative visual acuity (VA) and intraocular pressure (IOP). P-values less than 0.05 were considered statistically significant. Twenty-one patients were included in the study; twelve were male (57.1%) and nine were female (42.9%). The mean age was 55.38 ± 17.67 years (range 9–75 years). The mean follow-up duration was 5.95 ± 3.14 months (range 2–12 months). The mean log-MAR visual acuity was 1.26 ± 0.46 pre-operatively and 0.78 ± 0.57 post-operatively (P = 0.003). The change in intraocular pressure was not statistically significant. Complications included intraocular hypertension (over 21 mmHg) in 3 patients (14.3%) and macular edema, pupillar ovalization, and retinal detachment in one patient each. The results indicate that injection of an angular support foldable lens in the anterior chamber is a useful technique for the correction of aphakia in eyes without capsular support. More extended follow-up, however, and a larger series of patients are needed to ascertain the effectiveness and safety of this procedure. PMID:24324349

  15. Ceramic Matrix Composite Combustion Chamber for HAN-Based Monopropellants Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Ultramet will design and fabricate a lightweight, high temperature 5-lbf combustion chamber. The system will be designed for use with the AF-315 family of...

  16. Simulation of ionization-front-forming process at injection of relativistic electron beam with a gas chamber

    Energy Technology Data Exchange (ETDEWEB)

    Dolya, S.N.; Zhidkov, E.P.; Rubin, S.B.; Semerdzhiev, Kh.I.

    1982-01-01

    The methodical work on creation of computer program for numerical study of the processes of forming and motion of a virtual cathode at the injection of relativistic electron beam into a short cylindrical chamber, filled with gas, has been carried out. The obtained plots of the distributions of fields, potential and density appearing out of ion and electron gas of the beam itself are presented. The dependence of cross-section ionization on the electron velocity has been taken into account at the calculation; the resonance contribution into summarized cross-section of ionization was simulated. It is shown that the injection into the chamber without gas, some oscillations of the virtual cathode are observed. At the presence of the final front of the beam, the fields level at the initial stage is smaller than for the beam with a sharp front. However, in some time the field amplitudes are compared. The motion of simulated probe ions in the chamber is analyzed.

  17. Effects of heat treatment on the properties of powder injection molded AIN ceramics

    Institute of Scientific and Technical Information of China (English)

    DU Xueli; QIN Mingli; Akhtar Farid; FENG Peizhong; QU Xuanhui

    2008-01-01

    The effects of two different heat-treatment atmospheres,nitrogen atmosphere and reducing nitrogen atmosphere with carbon,on the properties of Y2O3-doped aluminum nitride (AlN) ceramics were investigated.The AlN powder as a raw material was synthesized by self-propagating high-temperature synthesis (SHS) and compacts were fabricated by employing powder injection molding technique.The polymer-wax binder consisted of 60 wt.% paraffin wax (PW),35 wt.% polypropylene (PP),and 5 wt.% stearic acid (SA).After the removal of binder,specimens were sintered at 1850℃ in nitrogen atmosphere under atmospheric pressure.To improve the thermal conductivity,sintered samples were reheated.The result reveals that the heat-treatment atmosphere has significant effect on the properties and secondary phase of AlN ceramics.The thermal conductivity and density of AlN ceramics reheated in nitrogen gas are 180 W·m-1 K-1 and 3.28 g,cm-3 and the secondary phase is yttrium aluminate.For the sample reheated in reducing nitrogen atmosphere with carbon,the thermal conductivity and density are 173 W.m-1.K-1 and 3.23 g·cm-3,respectively,and the secondary phase is YN.

  18. Spray combustion of biomass-based renewable diesel fuel using multiple injection strategy in a constant volume combustion chamber

    KAUST Repository

    Jing, Wei

    2016-05-26

    Effect of a two-injection strategy associated with a pilot injection on the spray combustion process was investigated under conventional diesel combustion conditions (1000 K and 21% O2 concentration) for a biomass-based renewable diesel fuel, i.e., biomass to liquid (BTL), and a regular No. 2 diesel in a constant volume combustion chamber using multiband flame measurement and two-color pyrometry. The spray combustion flame structure was visualized by using multiband flame measurement to show features of soot formation, high temperature and low temperature reactions, which can be characterized by the narrow-band emissions of radicals or intermediate species such as OH, HCHO, and CH. The objective of this study was to identify the details of multiple injection combustion, including a pilot and a main injection, and to provide further insights on how the two injections interact. For comparison, three injection strategies were considered for both fuels including a two-injection strategy (Case TI), single injection strategy A (Case SA), and single injection strategy B (Case SB). Multiband flame results show a strong interaction, indicated by OH emissions between the pilot injection and the main injection for Case TI while very weak connection is found for the narrow-band emissions acquired through filters with centerlines of 430 nm and 470 nm. A faster flame development is found for the main injection of Case TI compared to Cases SA and SB, which could be due to the high temperature environment and large air entrainment from the pilot injection. A lower soot level is observed for the BTL flame compared to the diesel flame for all three injection types. Case TI has a lower soot level compared to Cases SA and SB for the BTL fuel, while the diesel fuel maintains a similar soot level among all three injection strategies. Soot temperature of Case TI is lower for both fuels, especially for diesel. Based on these results, it is expected that the two-injection strategy could be

  19. Bisphosphonate-adsorbed ceramic nanoparticles increase bone formation in an injectable carrier for bone tissue engineering

    Directory of Open Access Journals (Sweden)

    Tegan L Cheng

    2015-10-01

    Full Text Available Sucrose acetate isobutyrate (SAIB is a sugar-based carrier. We have previously applied SAIB as a minimally invasive system for the co-delivery of recombinant human bone morphogenetic protein-2 (rhBMP-2 and found synergy when co-delivering zoledronic acid (ZA and hydroxyapatite (HA nanoparticles. Alternative bioceramics were investigated in a murine SAIB/rhBMP-2 injection model. Neither beta-tricalcium phosphate (TCP nor Bioglass (BG 45S5 had a significant effect on bone volume (BV alone or in combination with the ZA. 14C-labelled ZA binding assays showed particle size and ceramic composition affected binding with nano-HA > micro-HA > TCP > BG. Micro-HA and nano-HA increased BV in a rat model of rhBMP-2/SAIB injection (+278% and +337%, and BV was further increased with ZA–adsorbed micro-HA and nano-HA (+530% and +889%. These data support the use of ZA–adsorbed nanoparticle-sized HA as an optimal additive for the SAIB/rhBMP-2 injectable system for bone tissue engineering.

  20. Radon exhalation rates corrected for leakage and back diffusion – Evaluation of radon chambers and radon sources with application to ceramic tile

    Directory of Open Access Journals (Sweden)

    M. Abo-Elmagd

    2014-10-01

    Full Text Available The natural radon decay, leakage and back diffusion are the main removal processes of radon from its container. Ignoring these processes leads to underestimate the measured value of radon related parameters like exhalation rate and radium content. This work is aimed to evaluate two different radon chambers through determining their leakage rate λv and evaluation of radon source by determine its back diffusion rate λb inside the evaluated radon chambers as well as a small sealed cup. Two different methods are adapted for measuring both the leakage rate and the back diffusion rate. The leakage rate can be determined from the initial slope of the radon decay curve or from the exponential fitting of the whole decay curve. This can be achieved if a continuous monitoring of radon concentration inside the chamber is available. Also, the back diffusion rate is measured by sealing the radon source in the chamber and used the initial slope of the buildup curve to determine λb and therefore the exhalation rate of the source. This method was compared with simple equation for λb based on the ratio of the source to the chamber volume. The obtained results are applied to ceramic tile as an important radon source in homes. The measurement is targeted the ceramic glaze before and after firing as well as the obtained tile after adhere the glaze on the tile main body. Also, six different tile brands from Egyptian market are subjected to the study for comparison.

  1. Rheological and thermal performance of newly developed binder systems for ceramic injection molding

    Science.gov (United States)

    Hausnerova, Berenika; Kasparkova, Vera; Hnatkova, Eva

    2016-05-01

    In a novel binder system, carnauba wax was considered to replace the synthetic backbone polymers (polyolefins) enhancing the environmental sustainability of Ceramic Injection Molding (CIM) technology. The paper presents comparison of the rheological performance and thermal behavior of the aluminum oxide CIM feedstocks based on a binder containing carnauba wax with those consisting of a commercial binder. Further, acrawax (N, N'-Ethylene Bis-stearamide) has been considered as another possible substitute of polyolefins. For both proposed substitutes there is a significant reduction in viscosity, and in case of carnauba wax based feedstock also in processing temperature, which is essential for injection molding of reactive powders. Thermal characterization comprised analyses of single neat binders, their mixtures and mixtures with aluminum oxide. The presence of powder lowered melting temperatures of all tested binders except of polyolefin. Further depression in melting point of poly(ethylene glycol) is observed in combination with polyolefin in the presence of powder, and it is related to changes in size of the crystalline domains.

  2. Thermal Studies of the Laser Inertial Fusion Energy (LIFE) Target during Injection into the Fusion Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Miles, R. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Havstad, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); LeBlanc, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chang, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Golosker, I. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rosso, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-09-09

    The tests of the external heat transfer coefficient suggests that the values used in the numerical analysis for the temperature distribution within the fusion fuel target following flight into the target chamber are probably valid. The tests of the heat transfer phenomena occurring within the target due the rapid heating of the LEH window for the hot gasses within the fusion chamber show that the heat does indeed convect via the internal helium environment of the target towards the capsule and that the pressure in the front compartment of the target adjacent to the LEH window increases such that t bypass venting of the internal helium into the second chamber adjacent to the capsule is needed to prevent rupture of the membranes. The bypass flow is cooled by the hohlraum during this venting. However, the experiments suggest that our internal heat flow calculations may be low by about a factor of 2. Further studies need to be conducted to investigate the differences between the experiment and the numerical analysis. Future studies could also possibly bring the test conditions closer to those expected in the fusion chamber to better validate the results. A sacrificial layer will probably be required on the LEH window of the target and this can be used to mitigate any unexpected target heating.

  3. The Expression of the Plasmid DNA Encoding TGF-β1 in Endothelium after Injection into the Anterior Chamber

    Institute of Scientific and Technical Information of China (English)

    胡燕华; 黄琼; 姜发纲; 陈宏

    2002-01-01

    Summary: The method of gene transfer into corneal endothelium was investigated to provide afoundation for the study of TGF-β1 gene transfer to inhibit corneal graft rejection. Two days afterdirect injection of pMAM TGF-β1 mediated by liposome into the anterior chamber of rabbits, onehalf of corneas were made into paraffin slides and the endothelial layer was carefully torn from theother half to make a single layer slide of endothelia. By means of immunohistochemical technique,the plasmid pMAM TGF-β1 expression product TGF-β1 in the endothelia was detected. SpecificTGF-β1 expression was positive in the endothelia on both the paraffin slide and the single layerslide. The results showed that by direct injection into the anterior chamber, foreign plasmid DNAcould be transferred into the endothelia and its expression was obtained. This may provide a foun-dation for further study on TGF-β1 participating in local induction of corneal immune tolerance.

  4. Modeling of diesel/CNG mixing in a pre-injection chamber

    Science.gov (United States)

    Abdul-Wahhab, H. A.; Aziz, A. R. A.; Al-Kayiem, H. H.; Nasif, M. S.

    2015-12-01

    Diesel engines performance can be improved by adding combustible gases to the liquid diesel. In this paper, the propagation of a two phase flow liquid-gas fuel mixture into a pre-mixer is investigated numerically by computational fluid dynamics simulation. CNG was injected into the diesel within a cylindrical conduit operates as pre-mixer. Four injection models of Diesel-CNG were simulated using ANSYS-FLUENT commercial software. Two CNG jet diameters were used of 1 and 2 mm and the diesel pipe diameter was 9 mm. Two configurations were considered for the gas injection. In the first the gas was injected from one side while for the second two side entries were used. The CNG to Diesel pressure ratio was varied between 1.5 and 3. The CNG to Diesel mass flow ratios were varied between 0.7 and 0.9. The results demonstrate that using double-sided injection increased the homogeneity of the mixture due to the swirl and acceleration of the mixture. Mass fraction, in both cases, was found to increase as the mixture flows towards the exit. As a result, this enhanced mixing is likely to lead to improvement in the combustion performance.

  5. Material Characterization of Strontium Ferrite Powders for Producing Sintered Magnets by Ceramic Injection Molding (MagnetPIM)

    OpenAIRE

    Dietmar Drummer; Susanne Messingschlager

    2014-01-01

    For this study, different strontium ferrite powders were mixed with a filling ratio of about 60 vol% in a binder system and formed into green compacts. During the process of injection molding, a magnetic field was generated in the tool via a magnetic coil, which enables magnetization and orientation of the ceramic particles. All powders were successfully processed by MagnetPIM. The investigations identified that it is impossible to extrapolate from the magnetic properties of a green compact t...

  6. Ceramic micro-injection molded nozzles for serial femtosecond crystallography sample delivery

    Energy Technology Data Exchange (ETDEWEB)

    Beyerlein, K. R.; Heymann, M.; Kirian, R. [Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron, Notkestraße 85, 22607 Hamburg (Germany); Adriano, L.; Bajt, S., E-mail: sasa.bajt@desy.de [Photon Science, Deutsches Elektronen-Synchrotron, Notkestraße 85, 22607 Hamburg (Germany); Knoška, J. [Department of Physics, University of Hamburg, Luruper Chaussee 149, 22607 Hamburg (Germany); Wilde, F. [Helmholtz-Zentrum Geesthacht, Max-Planck-Straße 1, 21502 Geesthacht (Germany); Chapman, H. N. [Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron, Notkestraße 85, 22607 Hamburg (Germany); Department of Physics, University of Hamburg, Luruper Chaussee 149, 22607 Hamburg (Germany); Centre for Ultrafast Imaging, Notkestraße 85, 22607 Hamburg (Germany)

    2015-12-15

    Serial femtosecond crystallography (SFX) using X-ray Free-Electron Lasers (XFELs) allows for room temperature protein structure determination without evidence of conventional radiation damage. In this method, a liquid suspension of protein microcrystals can be delivered to the X-ray beam in vacuum as a micro-jet, which replenishes the crystals at a rate that exceeds the current XFEL pulse repetition rate. Gas dynamic virtual nozzles produce the required micrometer-sized streams by the focusing action of a coaxial sheath gas and have been shown to be effective for SFX experiments. Here, we describe the design and characterization of such nozzles assembled from ceramic micro-injection molded outer gas-focusing capillaries. Trends of the emitted jet diameter and jet length as a function of supplied liquid and gas flow rates are measured by a fast imaging system. The observed trends are explained by derived relationships considering choked gas flow and liquid flow conservation. Finally, the performance of these nozzles in a SFX experiment is presented, including an analysis of the observed background.

  7. The Injection of Air/Oxygen Bubble into the Anterior Chamber of Rabbits as a Treatment for Hyphema in Patients with Sickle Cell Disease

    Directory of Open Access Journals (Sweden)

    Emre Ayintap

    2014-01-01

    Full Text Available Purpose. To investigate the changes of partial oxygen pressure (PaO2 in aqueous humour after injecting air or oxygen bubble into the anterior chamber in sickle cell hyphema. Methods. Blood samples were taken from the same patient with sickle cell disease. Thirty-two rabbits were divided into 4 groups. In group 1 (n=8, there was no injection. Only blood injection constituted group 2 (n=8, both blood and air bubble injection constituted group 3 (n=8, and both blood and oxygen bubble injection constituted group 4 (n=8. Results. The PaO2 in the aqueous humour after 10 hours from the injections was 78.45 ± 9.9 mmHg (Mean ± SD for group 1, 73.97 ± 8.86 mmHg for group 2, 123.35 ± 13.6 mmHg for group 3, and 306.47 ± 16.5 mmHg for group 4. There was statistically significant difference between group 1 and group 2, when compared with group 3 and group 4. Conclusions. PaO2 in aqueous humour was increased after injecting air or oxygen bubble into the anterior chamber. We offer to leave an air bubble in the anterior chamber of patients with sickle cell hemoglobinopathies and hyphema undergoing an anterior chamber washout.

  8. Wetting and dispersion in ceramic/polymer melt injection molding systems: Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, M.D.; Williams, J.W.; Batich, C.D.

    1986-11-01

    Research progress is reported in the areas of rheological characterization, mixing/deagglomeration, ceramic/polymer interface modification, polymer matrix chemistry, and microstructure characterization. (DLC)

  9. Wetting and dispersion in ceramic/polymer melt injection molding systems

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, M.D. (Florida Univ., Gainesville, FL (United States). Dept. of Materials Science and Engineering); Williams, J.W. (Florida Univ., Gainesville, FL (United States). Dept. of Materials Science and Engineering 3M Co., St. Paul, MN (United States))

    1993-01-01

    This program had two major areas of emphasis: (1) factors influencing state of particulate dispersion and rheological properties of ceramic powder/polymer melt mixtures, and (2) effect of interfacial bonding strength on mechanical and rheological properties of ceramic particle/polymer composites. Alumina and silica in various polyethylenes were used.

  10. Wetting and dispersion in ceramic/polymer melt injection molding systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, M.D. [Florida Univ., Gainesville, FL (United States). Dept. of Materials Science and Engineering; Williams, J.W. [Florida Univ., Gainesville, FL (United States). Dept. of Materials Science and Engineering]|[3M Co., St. Paul, MN (United States)

    1993-05-01

    This program had two major areas of emphasis: (1) factors influencing state of particulate dispersion and rheological properties of ceramic powder/polymer melt mixtures, and (2) effect of interfacial bonding strength on mechanical and rheological properties of ceramic particle/polymer composites. Alumina and silica in various polyethylenes were used.

  11. In-flight behavior of dissimilar co-injected particles in the spraying of metal-ceramic functionally gradient materials

    Energy Technology Data Exchange (ETDEWEB)

    Fincke, J.R.; Swank, W.D.; Haggard, D.C. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1997-12-31

    In the spraying of functionally gradient coatings the particle ensemble delivered to the substrate can vary from a relatively low melting point metallic particle to a significantly higher melting point ceramic particle. At various stages in the spray process the particle ensemble can be either predominantly metallic, ceramic, or an intermediate combination. For co-injected particles the mixtures do not behave as a simple linear superposition of the spray patterns of the individual particle types. The particle temperature, velocity, size distributions, and pattern characteristics of the resulting spray fields is examined for all ceramic particle sprays (ZrO{sub 2}), all metallic particle sprays (NiCrAlY), and for a 1:1 mixture. The major particle-particle interaction occurs in the injector itself and results in a modified spray pattern which is different from that of either material sprayed alone. The particle velocity distributions generally exhibit a bimodal nature which is dependent on the size and density of the injected particles.

  12. The Impedance of Multi-layer Vacuum Chambers

    CERN Document Server

    Vos, L

    2003-01-01

    Many components of the LHC vacuum chamber have multi-layered walls : the copper coated cold beam screen, the titanium coated ceramic chamber of the dump kickers, the ceramic chamber of the injection kickers coated with copper stripes, only to name a few. Theories and computer programs are available for some time already to evaluate the impedance of these elements. Nevertheless, the algorithm developed in this paper is more convenient in its application and has been used extensively in the design phase of multi-layer LHC vacuum chamber elements. It is based on classical transmission line theory. Closed expressions are derived for simple layer configurations, while beam pipes involving many layers demand a chain calculation. The algorithm has been tested with a number of published examples and was verified with experimental data as well.

  13. Wetting and dispersion in ceramic/polymer melt injection molding systems

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, M.D.; Williams, J.W.; Batich, C.D.

    1985-11-01

    The major goal of this program is to achieve an improved understanding of the factors influencing dispersion of ceramic particles in polymer melts. In general, there are three requirements in the dispersion of a powder in a liquid medium (e.g., a polymer melt): (1) wetting of the powder by the liquid; (2) breaking up powder agglomerates; and (3) maintaining the dispersed state (e.g., avoiding particle coagulation). Work has been initiated in each of these areas. Preliminary results are described.

  14. Material Characterization of Strontium Ferrite Powders for Producing Sintered Magnets by Ceramic Injection Molding (MagnetPIM

    Directory of Open Access Journals (Sweden)

    Dietmar Drummer

    2014-01-01

    Full Text Available For this study, different strontium ferrite powders were mixed with a filling ratio of about 60 vol% in a binder system and formed into green compacts. During the process of injection molding, a magnetic field was generated in the tool via a magnetic coil, which enables magnetization and orientation of the ceramic particles. All powders were successfully processed by MagnetPIM. The investigations identified that it is impossible to extrapolate from the magnetic properties of a green compact to the magnetic properties of a sintered part. It became obvious, though, that, when producing very strong magnetic parts by MagnetPIM, the best results can be obtained by using powders with small particle sizes.

  15. Around the laboratories: Dubna: Physics results and progress on bubble chamber techniques; Stanford (SLAC): Operation of a very rapid cycling bubble chamber; Daresbury: Photographs of visitors to the Laboratory; Argonne: Charge exchange injection tests into the ZGS in preparation for a proposed Booster

    CERN Multimedia

    1969-01-01

    Around the laboratories: Dubna: Physics results and progress on bubble chamber techniques; Stanford (SLAC): Operation of a very rapid cycling bubble chamber; Daresbury: Photographs of visitors to the Laboratory; Argonne: Charge exchange injection tests into the ZGS in preparation for a proposed Booster

  16. A comparative study of metal and ceramic injection moulding for precision applications

    DEFF Research Database (Denmark)

    Islam, Aminul; Giannekas, Nikolaos; Marhöfer, David Maximilian;

    2015-01-01

    process presents a dilemma for choosing between MIM and CIMas both the material classes can offer specific advantages and the process steps are identical. So a comparative study about the process capabilities between CIM and MIM will be useful for thorough understanding of the processes and to select......Powder injection moulding (PIM) process is an attractive process as it combines the possibilities of net-shape and large-scale production with wide range of material varieties. This article presents a comparative study of two branches of PIM processes with the focus on precision application...

  17. Optimization of Alumina Slurry for Oxide-Oxide Ceramic Composites Manufactured by Injection Molding

    Directory of Open Access Journals (Sweden)

    Catherine Billotte

    2017-01-01

    Full Text Available This paper focuses on the rheological study of an alumina suspension intended for the manufacturing of oxide-oxide composites by flexible injection. Given the production constraints, it is required to have stable suspension with low viscosity and a Newtonian behavior. This is achieved with a concentration of nitric acid between 0.08 wt% and 0.2 wt% and amount of 3 wt% of PVA binder. The maximum loading of the suspension of 47 vol% suggests that there is no structure development within the suspension with optimized concentration of acid and PVA.

  18. Tailoring the heat transfer on the injection moulding cavity by plasma sprayed ceramic coatings

    Science.gov (United States)

    Bobzin, K.; Hopmann, Ch; Öte, M.; Knoch, M. A.; Alkhasli, I.; Dornebusch, H.; Schmitz, M.

    2017-03-01

    Inhomogeneous material shrinkage in injection moulding can cause warpage in thermoplastic components. To minimise the deformations of the injection moulding parts, the heat transfer during the cooling phase can be adjusted according to the local cooling demand on the surface of the mould cavity by means of plasma sprayed coatings with locally variable thermal resistance over the surface of the mould. Thermal resistance is a function of thermal conductivity and thickness of the coatings, where thermal conductivity of thermal barrier coatings can be adjusted by altering the chemical composition and the microstructure, which is depending on the thickness. This work evaluates the application of plasma sprayed coatings with variable thickness as thermal barrier coatings in the mould cavity. The thermal resistance of the coating and thereby the heat transfer from the melt into the mould will be influenced locally by varying the coating thickness over the cavity area according to the local cooling demand. Using the laser flash method, the thermal conduction of coatings with different thicknesses will be determined. On the basis of the experimentally determined thermal conduction, the effect of the coatings on the temperature field of the mould cavity will be numerically calculated and the required thickness distribution of the coating for an optimal temperature gradient will be determined.

  19. Continuous soil VOCl measurements with automated flux chambers and micro-ECD gas chromatography coupled with the thermal desorption and cooled injection systems

    Science.gov (United States)

    Molodovskaya, M. S.; Svensson, T.; Pitts, A.; Delmonte, J.; Nesic, Z.; Oberg, G.

    2010-12-01

    automated chamber was continuously pumped through the glass tubes filled with carbon-based absorbent (Carbotrap 300) to capture and retain VOCl. At the end of each measurement period, the tubes are brought back to the lab, and the content is analyzed by Agilent 7890 GC/micro-ECD coupled with the Gerstel Thermal Desorption System (TDS) and Cooled Injection System (CIS). The ultra sensitive micro-ECD detection and high-efficiency capillary column (Rtx®-VMS, 20m x 0.18mm ID x 1.0µm) allows rapid separation and quantification of the mid-weight VOCl such as chloroform, carbon tetrachloride, 1,1,1-trichloroethane and bromochloromethane. The GC-method dynamic range is linear within 0.1-200.0ng, and the analytical precision is determined to be 4%. The described system can be used for the analysis of soil/atmosphere exchange of VOCl at the detection limit of 1.9ng m-2 h-1, which is far below previously reported average soil emission levels from forest soils. The high precision GC analysis combined with the automatic chambers makes it possible to study the high spatial and temporal variability of soil VOCl fluxes.

  20. 陶瓷绘画中戏曲《西厢记》的艺术解读%THE ART INTERPRETATION FOR TRADITIONAL OPERA——ROMANCE OF WESTERN CHAMBER IN CERAMIC

    Institute of Scientific and Technical Information of China (English)

    朱景燕; 董小军

    2012-01-01

    Ceramics and traditional opera are the art treasure of chinese Han nationality,which have long history and rich connotation.The traditional opera—Romance of Western Chamber is the realism masterpiece of classic opera in our country.In the history of chinese porcelain,the ceramic arts which are painted based on Romance of Western Chamber are exquisite beyond compare.The work of art fully display unique wisdom and aesthetic taste of chinese nation.%陶瓷与戏曲都是华夏汉民族的艺术瑰宝,有着悠久的历史和丰富的文化内涵。戏曲《西厢记》是我国古典戏剧的现实主义杰作。而中国制瓷史上以西厢人物为范本绘制出的陶瓷艺术品也精美绝伦,这些艺术品充分展现了华夏民族的独特智慧和审美情趣。

  1. Sample introduction systems for reversed phase LC-ICP-MS of selenium using large amounts of methanol - comparison of systems based on membrane desolvation, a spray chamber and direct injection

    DEFF Research Database (Denmark)

    Bendahl, L.; Gammelgaard, Bente

    2005-01-01

    nebuliser (MCN) in combination with a membrane desolvator ( MD), a MCN in combination with a cyclonic spray chamber ( CS) and a direct injection nebuliser ( DIN), respectively. Thirteen selenium standards diluted in 50% methanol were introduced in each system at a flow rate of 50 mu l min(-1). Except...

  2. Constante de mola de molas cerâmicas injetadas a baixa pressão Spring constant of low-pressure injection molded ceramic springs

    Directory of Open Access Journals (Sweden)

    R. A. Barbieri

    2011-12-01

    the forming processes of green ceramics, or create new processes to obtain the near net shape parts. The production of ceramic parts with complex shapes, free of defects, is a task that involves great difficulties. Ceramic springs exhibits shapes extremely difficult to be molded and therefore are currently commercially produced mainly by machining, a process which is difficult and expensive. An alternative for the production of ceramic springs is by low-pressure injection molding. For the development of ceramic springs for technological applications, it is required in addition to getting parts intact and free of defects, to measure some of its properties, including the spring constant. Since these springs are usually applied at high temperatures, it becomes important to carry out the measurement of resistance imposed by the spring to elastic deformation at different temperatures. Accordingly, in this work we describe the assembly of an experiment for the measurement of the spring constant of low-pressure injection molded ceramic springs, both at ambient temperature and at high temperatures, using the dynamic impulse excitation method to measure the frequency of vibration of a suspended spring inside a furnace. Results are presented for a helical spring of alumina from room temperature to1100 ºC to illustrate the application of this technique.

  3. Focused-microwave-assisted reaction in flow injection spectrophotometry: a new liquid-vapor separation chamber for determination of reducing sugars in wine.

    Science.gov (United States)

    Oliveira, A F; Fatibello-Filho, O; Nóbrega, J A

    2001-10-31

    The usefulness of an unsegmented liquid/vapor phases flow injection system for determining reducing sugars in wines using a focalized poly(tetrafluoroethylene) (PTFE) coiled reactor positioned at the output antenna of a domestic microwave oven at 700 W is demonstrated. In this system, sample or reference solution is mixed to 2.5 mol l(-1) sodium hydroxide and 6.8 mmol l(-1) potassium hexacyanoferrate(III) solutions previously merged in a confluence point and the reducing sugars (glucose plus fructose) were oxidized by potassium hexacyanoferrate(III) solution into the PTFE coiled reactor positioned in the microwave oven cavity. After phases separation at a proposed separation chamber (SC), the decrease of K(3)Fe(CN)(6) concentration in the liquid phase was measured at 420 nm. Using this SC, a favorable dispersion profile and a decrease of hydrodynamic pressure were observed. The flow procedure presented similar sensitivities to glucose and fructose in the experimental conditions adopted, allowing the determination of the reducing sugars content (fructose plus glucose concentrations) in the concentration range from 40 to 400 mumol l(-1) with a detection limit of 9 mumol l(-1). The RSD was 1.9% for a 120 mumol l(-1) fructose solution (n=12) and the analytical frequency was 54 h(-1). The results obtained for reducing sugars in several wines using the proposed flow system and those obtained using the Somogyi-Nelson batch procedure were in agreement at the 95% confidence level.

  4. Design of Injection Cylinder for J1170 Horizontal Cold Chamber Die-casting Machine%J1170型卧式冷室压铸机压射缸结构设计

    Institute of Scientific and Technical Information of China (English)

    张海华

    2013-01-01

    The injection cylinder structure of J1170 horizontal cold chamber die-casting machine was designed,and the injection cylinder structure size was calculated.Combining with practical application,the characters of the design were analyzed.%设计J1170型卧式冷室压铸机压射缸结构,对压射缸的结构尺寸进行理论计算;结合实际应用,分析其设计特点.

  5. Laser melt injection of hard ceramic particles into Al and Ti alloys - processing, microstructure and mechanical behavior

    NARCIS (Netherlands)

    Ocelik, V; Nijman, S; van Ingen, R; Oliveira, U; De Hosson, J Th M

    2003-01-01

    The conditions for a successful Laser Melt Injection (LMI) of SiC and WC particles into the melt pool of Al8Si and Ti6Al4V alloys were studied exptl. and theor. by FEM calcns. The laser employed is a high power Nd:YAG. The formation of a relatively thick aluminum oxide layer on the Al melt surface w

  6. Laser melt injection of hard ceramic particles into Al and Ti alloys - processing, microstructure and mechanical behaviour

    NARCIS (Netherlands)

    Ocelik, V.; Nijman, S.; van Ingen, R.; Oliveira, U.; de Hosson, J.T.M.; Brebbia, CA; DeHosson, JTM; Nishida, SI

    2003-01-01

    The conditions for a successful Laser Melt Injection (LMI) of SiC and WC particles into the melt pool of Al8Si and Ti6A14V alloys were studied experimentally and theoretically by FEM calculations. The laser employed is a high power Nd:YAG. The formation of a relatively thick aluminium oxide layer on

  7. Vacuum Chamber for the Booster Bending Magnets

    CERN Multimedia

    1974-01-01

    To minimize eddy currents, induced by the rising magnetic field, the chamber was made from thin stainless steel of high specific electric resistance. For mechanical stength, it was corrugated in a hydro-forming process. The chamber is curved, to follow the beam's orbital path. Under vacuum, the chamber tends to staighten, the ceramic spacer along half of its length keeps it in place (see also 7402458).

  8. spark chamber

    CERN Multimedia

    A few cosmic rays pass through your body every second of every day, no matter where you are. Look at the spark chamber to your right – every flash is the track made by a cosmic ray from outer space. The spark chamber is filled with a special gas mixture. Cosmic rays knock electrons out of the atoms in the gas. These electrons accelerate towards high voltage metal strips layered throughout the chamber, creating sparks like little bolts of lightning.

  9. spark chamber

    CERN Multimedia

    A few cosmic rays pass through your body every second of every day, no matter where you are. Look at the spark chamber to your right – every flash is the track made by a cosmic ray from outer space. The spark chamber is filled with a special gas mixture. Cosmic rays knock electrons out of the atoms in the gas. These electrons accelerate towards high voltage metal strips layered throughout the chamber, creating sparks like little bolts of lightning.

  10. Reuse of the red brick waste and dust waste of blasting chamber (glass micro spheres) in the red ceramic industry; Reaproveitamento dos residuos de tijolos vermelhos e do residuo de poeira da camara de jateamento (micro esferas de vidro) na industria de ceramica vermelha

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, R.A.; Felippe, C.E.C.; Guimaraes, C.S.; Almeida, V.C., E-mail: valeria@eq.ufrj.b [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Centro de Tecnologia. Escola de Quimica

    2010-07-01

    The search for alternative environmentally less aggressive disposal of solid waste has been adopted to reverse the negative scenario established by the improper disposal of these materials. The aim of this study was to evaluate the reuse of waste: leftover red brick from the civil construction and glass micro spheres, obtained from the blasting chamber, aiming to develop a ceramic product. Mixtures containing various amounts of waste were prepared. The ceramic pieces were burned at 1000 and 1200 deg C being tested for water absorption and tensile strength and characterized by X-ray diffraction. The analysis of volatile organic compounds released during the burning process was performed. The results indicate that the ceramic material produced has a high resistance although the analysis of gases from the burning point to a negative environmental impact. (author)

  11. wire chamber

    CERN Multimedia

    Proportional multi-wire chamber. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle. Proportional wire chambers allow a much quicker reading than the optical or magnetoscriptive readout wire chambers.

  12. Wire Chamber

    CERN Multimedia

    Magnetoscriptive readout wire chamber. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  13. wire chamber

    CERN Multimedia

    1967-01-01

    Magnetoscriptive readout wire chamber.Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  14. Portfolio: Ceramics.

    Science.gov (United States)

    Hardy, Jane; And Others

    1982-01-01

    Describes eight art activities using ceramics. Elementary students created ceramic tiles to depict ancient Egyptian and medieval European art, made ceramic cookie stamps, traced bisque plates on sketch paper, constructed clay room-tableaus, and designed clay relief masks. Secondary students pit-fired ceramic pots and designed ceramic Victorian…

  15. Portfolio: Ceramics.

    Science.gov (United States)

    Hardy, Jane; And Others

    1982-01-01

    Describes eight art activities using ceramics. Elementary students created ceramic tiles to depict ancient Egyptian and medieval European art, made ceramic cookie stamps, traced bisque plates on sketch paper, constructed clay room-tableaus, and designed clay relief masks. Secondary students pit-fired ceramic pots and designed ceramic Victorian…

  16. Wire Chamber

    CERN Multimedia

    1986-01-01

    Two wire chambers made originally for the R807 Experiment at CERN's Intersecting Storage Rings. In 1986 they were used for the PS 201 experiment (Obelix Experiment) at LEAR, the Low Energy Antiproton Ring. The group of researchers from Turin, using the chambers at that time, changed the acquisition system using for the first time 8 bit (10 bit non linear) analog to digital conversion for incoming signals from the chambers. The acquisition system was controlled by 54 CPU and 80 digital signal processors. The power required for all the electronics was 40 kW. For the period, this system was one of the most powerful on-line apparatus in the world. The Obelix Experiment was closed in 1996. To find more about how a wire chamber works, see the description for object CERN-OBJ-DE-038.

  17. Chamber dynamic research with pulsed power

    Energy Technology Data Exchange (ETDEWEB)

    PETERSON,ROBERT R.; OLSON,CRAIG L.; RENK,TIMOTHY J.; ROCHAU,GARY E.; SWEENEY,MARY ANN

    2000-05-15

    In Inertial Fusion Energy (IFE), Target Chamber Dynamics (TCD) is an integral part of the target chamber design and performance. TCD includes target output deposition of target x-rays, ions and neutrons in target chamber gases and structures, vaporization and melting of target chamber materials, radiation-hydrodynamics in target chamber vapors and gases, and chamber conditions at the time of target and beam injections. Pulsed power provides a unique environment for IFE-TCD validation experiments in two important ways: they do not require the very clean conditions which lasers need and they currently provide large x-ray and ion energies.

  18. wire chamber

    CERN Multimedia

    Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  19. wire chamber

    CERN Multimedia

    Was used in ISR (Intersecting Storage Ring) split field magnet experiment. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  20. Wire chamber

    CERN Multimedia

    Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  1. wire chamber

    CERN Multimedia

    1985-01-01

    Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  2. Study on a small diesel engine with direct injection impinging distribution spray combustion system. Optimum of injection system and combustion chamber; Shototsu kakusan hoshiki kogata diesel kikan ni kansuru kenkyu. Funshakei to nenshoshitsu no saitekika

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, K.; Kato, S.; Saito, T. [Kanazawa Institute of Technology, Ishikawa (Japan); Tanabe, H. [Gunma University, Gunma (Japan)

    1997-10-01

    This study is concerned with a small bore (93mm) diesel engine using impinged fuel spray, named OSKA system. The higher rate of injection show lower smoke emission with higher NOx Emission. The exhaust emission and performance were investigated under different compression ratio with higher rate of injection. The experimental results show that this OSKA system is capable for reducing the smoke emission without the deterioration of NOx emission and fuel consumption compared with the conventional DI diesel engine. 5 refs., 8 figs., 3 tabs.

  3. Liquid Wall Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Meier, W R

    2011-02-24

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  4. Integrally cored ceramic investment casting mold fabricated by ceramic stereolithography

    Science.gov (United States)

    Bae, Chang-Jun

    Superalloy airfoils are produced by investment casting (IC), which uses ceramic cores and wax patterns with ceramic shell molds. Hollow cored superalloy airfoils in a gas turbine engine are an example of complex IC parts. The complex internal hollow cavities of the airfoil are designed to conduct cooling air through one or more passageways. These complex internal passageways have been fabricated by a lost wax process requiring several processing steps; core preparation, injection molding for wax pattern, and dipping process for ceramic shell molds. Several steps generate problems such as high cost and decreased accuracy of the ceramic mold. For example, costly tooling and production delay are required to produce mold dies for complex cores and wax patterns used in injection molding, resulting in a big obstacle for prototypes and smaller production runs. Rather than using separate cores, patterns, and shell molds, it would be advantageous to directly produce a mold that has the casting cavity and the ceramic core by one process. Ceramic stereolithography (CerSLA) can be used to directly fabricate the integrally cored ceramic casting mold (ICCM). CerSLA builds ceramic green objects from CAD files from many thin liquid layers of powder in monomer, which are solidified by polymerization with a UV laser, thereby "writing" the design for each slice. This dissertation addresses the integrally cored casting ceramic mold (ICCM), the ceramic core with a ceramic mold shell in a single patternless construction, fabricated by ceramic stereolithography (CerSLA). CerSLA is considered as an alternative method to replace lost wax processes, for small production runs or designs too complex for conventional cores and patterns. The main topic is the development of methods to successfully fabricate an ICCM by CerSLA from refractory silica, as well as related issues. The related issues are the segregation of coarse fused silica powders in a layer, the degree of segregation parameter to

  5. Decreased emissions of CO and NO{sub x} by injection of ammonium sulphate into the combustion chamber; Minskade utslaepp av CO och NO{sub x} genom dosering av ammoniumsulfat i foerbraenningsrummet

    Energy Technology Data Exchange (ETDEWEB)

    Kassman, Haakan; Andersson, Christer; Carlsson, Jonas; Bjoerklund, Ulf; Stroemberg, Birgitta

    2005-02-01

    The purpose of the project was to investigate the possibilities of reducing the emissions of CO, NO{sub x} and NH{sub 3} from biomass-fired boilers by injection of ammonium sulphate to the combustion chamber. Particular focus was directed on addition of ammonium sulphate to the fuel and to the combustion air. This was expected to give an efficient oxidation of CO. The strategy was to use this reduction of the CO level to reduce the air excess and thereby to reduce the NO{sub x} emissions. This method for reduction of NO{sub x} was predicted to be less sensitive to variations in the operating conditions compared to conventional SNCR. The method could also enable reduction of NO{sub x} in boilers less suitable for SNCR, e.g. in cases when the flue gas temperature is too high (> 950 deg C) when the gases enters the superheaters. Experiments have been carried out in a pilot-scale facility at TPS and in full-scale in a 110 MW{sub th} BFB in Eskilstuna. This was done to show where, how and in which amounts ammonium sulphate should be injected to give the lowest possible emissions of CO, NO{sub x} and NH{sub 3}. A literature survey has been made in order to find the mechanisms of oxidation of CO during addition of sulphur. Furthermore, experiences from addition of sulphur and sulphates to combustion facilities have been compiled. The injection of ammonium sulphate to the combustion zone (fuel, secondary air or tertiary air) and to the SNCR-zone (directly downstream the combustion zone) reduced the CO emissions in general by 20-60%. Injection in the tertiary air was somewhat more efficient than the other positions. A reduction of approximately 45 % was achieved with an addition of sulphate corresponding to {approx}23 mg sulphur per MJ fuel. Increased content of CO gave a higher degree of reduction. Injection of ammonia to the SNCR zone had the opposite effect and increased the emissions of CO. The literature survey and the pilot-scale tests in the project have not

  6. Decreased emissions of CO and NO{sub x} by injection of ammonium sulphate into the combustion chamber; Minskade utslaepp av CO och NO{sub x} genom dosering av ammoniumsulfat i foerbraenningsrummet

    Energy Technology Data Exchange (ETDEWEB)

    Kassman, Haakan; Andersson, Christer; Carlsson, Jonas; Bjoerklund, Ulf; Stroemberg, Birgitta

    2005-02-01

    The purpose of the project was to investigate the possibilities of reducing the emissions of CO, NO{sub x} and NH{sub 3} from biomass-fired boilers by injection of ammonium sulphate to the combustion chamber. Particular focus was directed on addition of ammonium sulphate to the fuel and to the combustion air. This was expected to give an efficient oxidation of CO. The strategy was to use this reduction of the CO level to reduce the air excess and thereby to reduce the NO{sub x} emissions. This method for reduction of NO{sub x} was predicted to be less sensitive to variations in the operating conditions compared to conventional SNCR. The method could also enable reduction of NO{sub x} in boilers less suitable for SNCR, e.g. in cases when the flue gas temperature is too high (> 950 deg C) when the gases enters the superheaters. Experiments have been carried out in a pilot-scale facility at TPS and in full-scale in a 110 MW{sub th} BFB in Eskilstuna. This was done to show where, how and in which amounts ammonium sulphate should be injected to give the lowest possible emissions of CO, NO{sub x} and NH{sub 3}. A literature survey has been made in order to find the mechanisms of oxidation of CO during addition of sulphur. Furthermore, experiences from addition of sulphur and sulphates to combustion facilities have been compiled. The injection of ammonium sulphate to the combustion zone (fuel, secondary air or tertiary air) and to the SNCR-zone (directly downstream the combustion zone) reduced the CO emissions in general by 20-60%. Injection in the tertiary air was somewhat more efficient than the other positions. A reduction of approximately 45 % was achieved with an addition of sulphate corresponding to {approx}23 mg sulphur per MJ fuel. Increased content of CO gave a higher degree of reduction. Injection of ammonia to the SNCR zone had the opposite effect and increased the emissions of CO. The literature survey and the pilot-scale tests in the project have not

  7. On Ceramics.

    Science.gov (United States)

    School Arts, 1982

    1982-01-01

    Presents four ceramics activities for secondary-level art classes. Included are directions for primitive kiln construction and glaze making. Two ceramics design activities are described in which students make bizarrely-shaped lidded jars, feet, and footwear. (AM)

  8. Dry low NOx combustion system with pre-mixed direct-injection secondary fuel nozzle

    Science.gov (United States)

    Zuo, Baifang; Johnson, Thomas; Ziminsky, Willy; Khan, Abdul

    2013-12-17

    A combustion system includes a first combustion chamber and a second combustion chamber. The second combustion chamber is positioned downstream of the first combustion chamber. The combustion system also includes a pre-mixed, direct-injection secondary fuel nozzle. The pre-mixed, direct-injection secondary fuel nozzle extends through the first combustion chamber into the second combustion chamber.

  9. Chamber transport

    Energy Technology Data Exchange (ETDEWEB)

    OLSON,CRAIG L.

    2000-05-17

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

  10. Relation between microstructure and dielectric breakdown in the case of aluminous ceramics (SEMM method); Comportement d'alumines face a l'injection de charges. Relation microstructure - claquage dielectrique - mesure des charges d'influence (methode SEMM)

    Energy Technology Data Exchange (ETDEWEB)

    Liebault, J.

    1999-02-01

    The dielectric breakdown is strongly linked to the injection and the accumulation of charges in a non-conducting material. The physics of charged insulators proposes mechanisms of trapping and transport of charges in aluminium oxides by considering defects as localization sources of charges and of energy. In order to measure the influence of defects on dielectric breakdown, various aluminous ceramics have been elaborated. The nature and the quantity of defects have been characterized by the nature and the rate of impurities, by porosity, by the quantity of grain boundaries and by the presence and distribution of secondary phases. These materials have undergone breakdown tests. The dielectric rigidity depends strongly on the nature and the distribution of crystallographic defects (vacancy, interstitial ions and dislocation), on the other hand porosity below 5% has no influence. The doping of an alumina ceramic containing less than 100 ppm of impurities implies a diminution of its dielectric rigidity. The measurement of the SEMM (scanning electron microscopy mirror) effect allows the characterization of insulating materials. This method permits the evaluation of the ability for materials to trap charges, it gives information about the charge kinetic of trapping, charge localization and the energy levels of traps. (A.C.)

  11. Application of Reaction-Bonded Silicon Carbide in Manufacturing of Spacecraft Combustion Chamber

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Silicon carbide (SiC) ceramics is a good structural ceramics material, which have a lot of excellent properties such as superior high-temperature strength up to a temperature of 1 350 ℃, chemical stability, good resistance to thermal shock and high abrasion resistance. The silicon carbide ceramics material has so far been used widely for manufacturing various components such as heat exchangers, rolls, rockets combustion chamber. Sintering of ceramics structural parts have many technological method, the reac...

  12. Drift chambers for a precision measurement of the Michel parameters in muon decay

    CERN Document Server

    Davydov, Y; Comyn, M; Depommier, P; Doornbos, J; Faszer, W; Gagliardi, C A; Gill, D R; Green, P; Gumplinger, P; Hardy, J C; Hasinoff, M D; Helmer, R; Henderson, R; Khruchinsky, A; Kitching, P; Koetke, D D; Korkmaz, E J; Lachin, Yu Yu; Maas, D; MacDonald, J A; MacDonald, R; Manweiler, R; Marshall, G; Mathie, E L; Miassoedov, L; Musser, J R; Nord, P M; Olin, A; Openshaw, R; Ottewell, D; Porcelli, T; Poutissou, J M; Poutissou, R; Price, G; Quraan, M A; Rodning, N L; Schaapman, J; Selivanov, V; Sheffer, G; Shin, B; Sobratee, F; Soukup, J; Stanislaus, T D S; Stinson, G M; Tacik, R; Torokhov, V D; Tribble, R E; Vasilev, M A; Walter, H C; Wright, D

    2001-01-01

    Planar drift chambers will be used in a solenoidal magnetic field to measure the Michel parameters in muon decay. The chamber manufacture procedure uses flat glass tables and precise ceramic glass spacers to provide precise anode-cathode spacing. Results of bench and beam tests of the prototype chambers are discussed.

  13. Ceramic joining

    Energy Technology Data Exchange (ETDEWEB)

    Loehman, R.E. [Sandia National Lab., Albuquerque, NM (United States)

    1996-04-01

    This paper describes the relation between reactions at ceramic-metal interfaces and the development of strong interfacial bonds in ceramic joining. Studies on a number of systems are described, including silicon nitrides, aluminium nitrides, mullite, and aluminium oxides. Joints can be weakened by stresses such as thermal expansion mismatch. Ceramic joining is used in a variety of applications such as solid oxide fuel cells.

  14. Ceramic Processing

    Energy Technology Data Exchange (ETDEWEB)

    EWSUK,KEVIN G.

    1999-11-24

    Ceramics represent a unique class of materials that are distinguished from common metals and plastics by their: (1) high hardness, stiffness, and good wear properties (i.e., abrasion resistance); (2) ability to withstand high temperatures (i.e., refractoriness); (3) chemical durability; and (4) electrical properties that allow them to be electrical insulators, semiconductors, or ionic conductors. Ceramics can be broken down into two general categories, traditional and advanced ceramics. Traditional ceramics include common household products such as clay pots, tiles, pipe, and bricks, porcelain china, sinks, and electrical insulators, and thermally insulating refractory bricks for ovens and fireplaces. Advanced ceramics, also referred to as ''high-tech'' ceramics, include products such as spark plug bodies, piston rings, catalyst supports, and water pump seals for automobiles, thermally insulating tiles for the space shuttle, sodium vapor lamp tubes in streetlights, and the capacitors, resistors, transducers, and varistors in the solid-state electronics we use daily. The major differences between traditional and advanced ceramics are in the processing tolerances and cost. Traditional ceramics are manufactured with inexpensive raw materials, are relatively tolerant of minor process deviations, and are relatively inexpensive. Advanced ceramics are typically made with more refined raw materials and processing to optimize a given property or combination of properties (e.g., mechanical, electrical, dielectric, optical, thermal, physical, and/or magnetic) for a given application. Advanced ceramics generally have improved performance and reliability over traditional ceramics, but are typically more expensive. Additionally, advanced ceramics are typically more sensitive to the chemical and physical defects present in the starting raw materials, or those that are introduced during manufacturing.

  15. Doriot Climatic Chambers

    Data.gov (United States)

    Federal Laboratory Consortium — The Doriot Climatic Chambers are two, 60-feet long, 11-feet high, 15-feet wide chambers that are owned and operated by NSRDEC. The Doriot Climatic Chambers are among...

  16. Directed Energy Anechoic Chamber

    Data.gov (United States)

    Federal Laboratory Consortium — The Directed Energy Anechoic Chamber comprises a power anechoic chamber and one transverse electromagnetic cell for characterizing radiofrequency (RF) responses of...

  17. [Ceramic posts].

    Science.gov (United States)

    Mainjot, Amélie; Legros, Caroline; Vanheusden, Alain

    2006-01-01

    As a result of ceramics and all-ceram technologies development esthetic inlay core and abutments flooded the market. Their tooth-colored appearance enhances restoration biomimetism principally on the marginal gingiva area. This article reviews indications and types of cores designed for natural teeth and implants.

  18. Ceramic Methyltrioxorhenium

    CERN Document Server

    Herrmann, R; Eickerling, G; Helbig, C; Hauf, C; Miller, R; Mayr, F; Krug von Nidda, H A; Scheidt, E W; Scherer, W; Herrmann, Rudolf; Troester, Klaus; Eickerling, Georg; Helbig, Christian; Hauf, Christoph; Miller, Robert; Mayr, Franz; Nidda, Hans-Albrecht Krug von; Scheidt, Ernst-Wilhelm; Scherer, Wolfgang

    2006-01-01

    The metal oxide polymeric methyltrioxorhenium [(CH3)xReO3] is an unique epresentative of a layered inherent conducting organometallic polymer which adopts the structural motifs of classical perovskites in two dimensions (2D) in form of methyl-deficient, corner-sharing ReO5(CH3) octahedra. In order to improve the characteristics of polymeric methyltrioxorhenium with respect to its physical properties and potential usage as an inherentconducting polymer we tried to optimise the synthetic routes of polymeric modifications of 1 to obtain a sintered ceramic material, denoted ceramic MTO. Ceramic MTO formed in a solvent-free synthesis via auto-polymerisation and subsequent sintering processing displays clearly different mechanical and physical properties from polymeric MTO synthesised in aqueous solution. Ceramic MTO is shown to display activated Re-C and Re=O bonds relative to MTO. These electronic and structural characteristics of ceramic MTO are also reflected by a different chemical reactivity compared with its...

  19. Absorbable-susceptor joining of ceramic surfaces

    Science.gov (United States)

    Schroeder, J. E.; Shlichta, P. J. (Inventor)

    1983-01-01

    An assembly of ceramic surfaces particularly refractory metal oxides and carbides, abutting a thin sheet of metal susceptor material are placed in a chamber of an enclosure containing inert gas. An RF coil is activated by power supply to melt the susceptor and adjacent zones of the ceramic. Reactive gas such as oxygen or a carbonizing gas is then fed to the chamber and reacts with the susceptor to form compounds which disperse and dissolve in the zones. On cooling, a strong joint is formed. The susceptor may contain inner perforations and outer perforations to aid in distribution of heat.

  20. The toxic effect observation of the retina after vitreous chamber injected with PDGFR-α ASODN%PDGFR-αASODN玻璃体内注射对视网膜的毒性作用

    Institute of Scientific and Technical Information of China (English)

    彭燕一; 李光辉; 秦程; 蒋姣姣

    2015-01-01

    in each time. ERG examination yielded no difference in the amplitude of b wave between the treated groups and the normal control group. Pathological changes of the retinal tissue were not observed in the examinations of HE and immunohistochemical at the day 28 after injection. Electron microscope observation of retinal photoreceptor cells in the group D showed the parts of gaps between membranous discs were expanding, parts of were fusing, a few of clearances around cell nucleus were slightly enlarged,and the shapes of the cell nucleus were slightly irregular. Conclusions To inject 0.1 mL PDGFR-αASODN/lip2000 into the vitreous chamber, PDGFR-αASODN can be relatively safe when its concentration is less than 1.5μmol/L.

  1. Develop of ceramic effects: surface finishes, through digital inject technology; Desarrollo de efectos ceramicos como acabados superficiales, mediante tecnologia de inyeccion digital

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Ferro Spain SA has tackled the practical viability of tile surfaces decoration by means of applying layers of reduced thickness by means of the use of digital injection technology by ink jet and, specifically, relating to effects and superficial finishes different from colouring. It has been studied several mechanisms which allow to get those effects and the influence of the main variables. It has also been assessed the obtained results dealing with the current regulations as in the case of non-slip effect. (Author)

  2. Contribution to the study of an lpg jet in the combustion chamber of a spark-ignition engine; Contribution a l'etude d'un jet de gpl dans la chambre de combustion d'un moteur a allumage commande, pour differentes strategies d'injection

    Energy Technology Data Exchange (ETDEWEB)

    Duong Viet, D.

    2002-07-01

    It appears tempting to combine the less polluting combustion of LPG with the energy performances of a direct injection spark-ignition engine. To this aim the study of high pressure injection of a liquid LPG jet, directly inside the combustion chamber of an engine was performed in two ways: Experimental studies: one with fast cinematography and another with the method of Doppler phases in an one-cylinder 'transparent' engine for various conditions of injection and without combustion. They respectively deliver empirical laws for the jet development and some informations about size and speed of the droplets of LPG. A modeling of the jet could then be made on the basis of a turbulent and deviated jet the parameters of which could be adjusted using results of the preceding experimental study. (author)

  3. Mush Column Magma Chambers

    Science.gov (United States)

    Marsh, B. D.

    2002-12-01

    Magma chambers are a necessary concept in understanding the chemical and physical evolution of magma. The concept may well be similar to a transfer function in circuit or time series analysis. It does what needs to be done to transform source magma into eruptible magma. In gravity and geodetic interpretations the causative body is (usually of necessity) geometrically simple and of limited vertical extent; it is clearly difficult to `see' through the uppermost manifestation of the concentrated magma. The presence of plutons in the upper crust has reinforced the view that magma chambers are large pots of magma, but as in the physical representation of a transfer function, actual magma chambers are clearly distinct from virtual magma chambers. Two key features to understanding magmatic systems are that they are vertically integrated over large distances (e.g., 30-100 km), and that all local magmatic processes are controlled by solidification fronts. Heat transfer considerations show that any viable volcanic system must be supported by a vertically extensive plumbing system. Field and geophysical studies point to a common theme of an interconnected stack of sill-like structures extending to great depth. This is a magmatic Mush Column. The large-scale (10s of km) structure resembles the vertical structure inferred at large volcanic centers like Hawaii (e.g., Ryan et al.), and the fine scale (10s to 100s of m) structure is exemplified by ophiolites and deeply eroded sill complexes like the Ferrar dolerites of the McMurdo Dry Valleys, Antarctica. The local length scales of the sill reservoirs and interconnecting conduits produce a rich spectrum of crystallization environments with distinct solidification time scales. Extensive horizontal and vertical mushy walls provide conditions conducive to specific processes of differentiation from solidification front instability to sidewall porous flow and wall rock slumping. The size, strength, and time series of eruptive behavior

  4. Engineering ceramics

    CERN Document Server

    Bengisu, Murat

    2001-01-01

    This is a comprehensive book applying especially to junior and senior engineering students pursuing Materials Science/ Engineering, Ceramic Engineering and Mechanical Engineering degrees. It is also a reference book for other disciplines such as Chemical Engineering, Biomedical Engineering, Nuclear Engineering and Environmental Engineering. Important properties of most engineering ceramics are given in detailed tables. Many current and possible applications of engineering ceramics are described, which can be used as a guide for materials selection and for potential future research. While covering all relevant information regarding raw materials, processing properties, characterization and applications of engineering ceramics, the book also summarizes most recent innovations and developments in this field as a result of extensive literature search.

  5. Structural Ceramics Database

    Science.gov (United States)

    SRD 30 NIST Structural Ceramics Database (Web, free access)   The NIST Structural Ceramics Database (WebSCD) provides evaluated materials property data for a wide range of advanced ceramics known variously as structural ceramics, engineering ceramics, and fine ceramics.

  6. ISR Intersection Vacuum Chamber

    CERN Multimedia

    1975-01-01

    This special vacuum chamber presenting a lateral opening at the beam crossing point is one of the many chambers specifically designed for a particular experiment. Here it is shown during assembly at the ISR mechanical worshop.

  7. LEP vacuum chamber, early prototype

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    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).

  8. Ceramic microfabrication by rapid prototyping process chains

    Indian Academy of Sciences (India)

    R Knitter; W Bauer

    2003-02-01

    Fabrication of micropatterned ceramics or ceramic microparts make high demands on the precision and resolution of the moulding process. As finishing of miniaturised or micropatterned ceramic components is nearly impossible, shaping has to be done by a replication step in the green, unfired state. To avoid high tooling costs in product development, a rapid prototyping process chain has been established that enables rapid manufacturing of ceramic microcomponents from functional models to small lot series within a short time. This process chain combines the fast and inexpensive supply of master models by rapid prototyping with accurate and flexible ceramic manufacturing by low-pressure injection moulding. Besides proper feedstock preparation and sufficient small grain size, the quality of the final components is mainly influenced by the quality of the master model. Hence, the rapid prototyping method must be carefully selected to meet the requirements of the component to be fabricated.

  9. Ceramic Seal.

    Energy Technology Data Exchange (ETDEWEB)

    Smartt, Heidi A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Romero, Juan A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Custer, Joyce Olsen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hymel, Ross W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Krementz, Dan [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Gobin, Derek [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Harpring, Larry [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Martinez-Rodriguez, Michael [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Varble, Don [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); DiMaio, Jeff [Tetramer Technologies, Pendleton, SC (United States); Hudson, Stephen [Tetramer Technologies, Pendleton, SC (United States)

    2016-11-01

    Containment/Surveillance (C/S) measures are critical to any verification regime in order to maintain Continuity of Knowledge (CoK). The Ceramic Seal project is research into the next generation technologies to advance C/S, in particular improving security and efficiency. The Ceramic Seal is a small form factor loop seal with improved tamper-indication including a frangible seal body, tamper planes, external coatings, and electronic monitoring of the seal body integrity. It improves efficiency through a self-securing wire and in-situ verification with a handheld reader. Sandia National Laboratories (SNL) and Savannah River National Laboratory (SRNL), under sponsorship from the U.S. National Nuclear Security Administration (NNSA) Office of Defense Nuclear Nonproliferation Research and Development (DNN R&D), have previously designed and have now fabricated and tested Ceramic Seals. Tests have occurred at both SNL and SRNL, with different types of tests occurring at each facility. This interim report will describe the Ceramic Seal prototype, the design and development of a handheld standalone reader and an interface to a data acquisition system, fabrication of the seals, and results of initial testing.

  10. A model to forecast magma chamber rupture

    Science.gov (United States)

    Browning, John; Drymoni, Kyriaki; Gudmundsson, Agust

    2016-04-01

    An understanding of the amount of magma available to supply any given eruption is useful for determining the potential eruption magnitude and duration. Geodetic measurements and inversion techniques are often used to constrain volume changes within magma chambers, as well as constrain location and depth, but such models are incapable of calculating total magma storage. For example, during the 2012 unrest period at Santorini volcano, approximately 0.021 km3 of new magma entered a shallow chamber residing at around 4 km below the surface. This type of event is not unusual, and is in fact a necessary condition for the formation of a long-lived shallow chamber. The period of unrest ended without culminating in eruption, i.e the amount of magma which entered the chamber was insufficient to break the chamber and force magma further towards the surface. Using continuum-mechanics and fracture-mechanics principles, we present a model to calculate the amount of magma contained at shallow depth beneath active volcanoes. Here we discuss our model in the context of Santorini volcano, Greece. We demonstrate through structural analysis of dykes exposed within the Santorini caldera, previously published data on the volume of recent eruptions, and geodetic measurements of the 2011-2012 unrest period, that the measured 0.02% increase in volume of Santorini's shallow magma chamber was associated with magmatic excess pressure increase of around 1.1 MPa. This excess pressure was high enough to bring the chamber roof close to rupture and dyke injection. For volcanoes with known typical extrusion and intrusion (dyke) volumes, the new methodology presented here makes it possible to forecast the conditions for magma-chamber failure and dyke injection at any geodetically well-monitored volcano.

  11. ALICE Injected Beam Accidents

    CERN Document Server

    Appleby, R B

    2009-01-01

    The ALICE (point 2) interaction region is sensitive to beam orbit errors arising from magnet setting errors on injection. In this report, beam accident scenarios under injection for ALICE are described, focusing on ultra- fast error injection scenarios for the interaction straight correctors and dipoles. Beam 1 and beam 2 accident scenarios are considered, where the errors can lead to beam orbits striking the ALICE vacuum chamber or elements of the machine. The required thresholds for magnet current interlocks are calculated to avoid machine and detector risk.

  12. LHCb Injected Beam Accidents

    CERN Document Server

    Appleby, R B

    2009-01-01

    The LHCb (point 8) interaction region is sensitive to beam orbit errors arising from magnet setting errors on injection. In this report, beam accident scenarios under injection for LHCb are described, focusing on ultra- fast error injection scenarios for the interaction straight correctors and dipoles. Beam 1 and beam 2 accident scenarios are considered, where the errors can lead to beam orbits striking the LHCb vacuum chamber or elements of the machine. The required thresholds for magnet current interlocks are calculated to avoid machine and detector risk.

  13. Emprego de nebulizador pneumático de ICP-MS como câmara de diluição em sistemas de injeção em fluxo para determinações multielementares Pneumatic nebulizer as a dilution chamber in a flow-injection system for multielement analysis by ICP-MS

    Directory of Open Access Journals (Sweden)

    José Anchieta Gomes Neto

    1998-07-01

    Full Text Available An automatic dispenser based on a flow-injection system used to introduce sample and analytical solution into an inductively coupled plasma mass spectrometer through a spray chamber is proposed. Analytical curves were constructed after the injection of 20 to 750 µL aliquots of a multielement standard solution (20.0 µg L-1 in Li, Be, Al, V, Cr, Mn, Ni, Co, Cu, Zn, As, Se, Sr, Ag, Cd, Ba, Tl, Pb and the acquisition of the integrated transient signals. The linear concentration range could be extended to ca. five decades. The performance of the system was checked by analyzing a NIST 1643d reference material. Accuracy could be improved by the proper selection of the injected volume. Besides good precision (r.s.d. < 2%, the results obtained with the proposed procedure were closer to the certified values of the reference material than those obtained by direct aspiration or by injecting 125 µL of several analytical solutions and samples.

  14. Streamer chamber: pion decay

    CERN Multimedia

    1992-01-01

    The real particles produced in the decay of a positive pion can be seen in this image from a streamer chamber. Streamer chambers consist of a gas chamber through which a strong pulsed electric field is passed, creating sparks as a charged particle passes through it. A magnetic field is added to cause the decay products to follow curved paths so that their charge and momentum can be measured.

  15. Prototype multiwire proportional chamber

    CERN Multimedia

    1975-01-01

    Chambers of this type were initially developed within the Alpha project (finally not approved). They were designed such to minimize the radiation length with a view to a mass spectrometer of high resolution meant to replace the Omega detector. The chambers were clearly forerunners for the (drift) chambers later built for R606 with the novel technique of crimping the wires. See also photo 7510039X.

  16. Electromagnetic reverberation chambers

    CERN Document Server

    Besnier, Philippe

    2013-01-01

    Dedicated to a complete presentation on all aspects of reverberation chambers, this book provides the physical principles behind these test systems in a very progressive manner. The detailed panorama of parameters governing the operation of electromagnetic reverberation chambers details various applications such as radiated immunity, emissivity, and shielding efficiency experiments.In addition, the reader is provided with the elements of electromagnetic theory and statistics required to take full advantage of the basic operational rules of reverberation chambers, including calibration proc

  17. Refrigeration Test Chamber

    Data.gov (United States)

    Federal Laboratory Consortium — The enclosed and environmentally controlled chamber is able to test four units (single-phase) simultaneously at conditions ranging from tundra to desert temperatures...

  18. DORIOT CLIMATIC CHAMBERS

    Data.gov (United States)

    Federal Laboratory Consortium — The Doriot Climatic Chambers reproduce environmental conditions occurring anywhere around the world. They provide an invaluable service by significantly reducing the...

  19. DELPHI time projection chamber

    CERN Multimedia

    1989-01-01

    The time projection chamber is inserted inside the central detector of the DELPHI experiment. Gas is ionised in the chamber as a charged particle passes through, producing an electric signal from which the path of the particle can be found. DELPHI, which ran from 1989 to 2000 on the LEP accelerator, was primarily concerned with particle identification.

  20. Fluidized bed combustion chamber

    Energy Technology Data Exchange (ETDEWEB)

    Kullendorff, A.; Wikner, J.

    1985-03-25

    The chamber is confined in a pressure vessel. The lower part of the chamber has tilted parallel gutters up to the height of the fluidized bed. The slope of the gutter walls is 5 degrees-15 degrees and the top area of the gutters is 1.3 to 3 times larger than their bottom.

  1. Target chambers for gammashpere

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, M.P.; Falout, J.W.; Nardi, B.G. [and others

    1995-08-01

    One of our responsibilities for Gammasphere, was designing and constructing two target chambers and associated beamlines to be used with the spectrometer. The first chamber was used with the early implementation phase of Gammasphere, and consisted of two spun-Al hemispheres welded together giving a wall thickness of 0.063 inches and a diameter of 12 inches.

  2. Climatic chamber ergometer

    CSIR Research Space (South Africa)

    Atkins, AR

    1968-01-01

    Full Text Available The design and calibration of an ergometer for exercising subjects during calorimetric studies in the climate chamber, are described. The ergometer is built into the climatic chamber and forms an integral part of the whole instrumentation system foe...

  3. BEBC bubble chamber

    CERN Multimedia

    1972-01-01

    Looking up into the interior of BEBC bubble chamber from the expansion cylinder. At the top of the chamber two fish-eye lenses are installed and three other fish-eye ports are blanked off. In the centre is a heat exchanger.

  4. The Mobile Chamber

    Science.gov (United States)

    Scharfstein, Gregory; Cox, Russell

    2012-01-01

    A document discusses a simulation chamber that represents a shift from the thermal-vacuum chamber stereotype. This innovation, currently in development, combines the capabilities of space simulation chambers, the user-friendliness of modern-day electronics, and the modularity of plug-and-play computing. The Mobile Chamber is a customized test chamber that can be deployed with great ease, and is capable of bringing payloads at temperatures down to 20 K, in high vacuum, and with the desired metrology instruments integrated to the systems control. Flexure plans to lease Mobile Chambers, making them affordable for smaller budgets and available to a larger customer base. A key feature of this design will be an Apple iPad-like user interface that allows someone with minimal training to control the environment inside the chamber, and to simulate the required extreme environments. The feedback of thermal, pressure, and other measurements is delivered in a 3D CAD model of the chamber's payload and support hardware. This GUI will provide the user with a better understanding of the payload than any existing thermal-vacuum system.

  5. CHAMBER OF COMMERCE INFORMATION

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Experience Japan The Japanese Chamber of Commerce and Industry will further promote its Japan-experience program and seek cooperation with various Chinese institutions.Between early May and June 2007,the chamber organized a Chinese college student delegation to Japan with the support from its members in China.

  6. PS wire chamber

    CERN Multimedia

    1970-01-01

    A wire chamber used at CERN's Proton Synchrotron accelerator in the 1970s. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  7. OPAL Jet Chamber Prototype

    CERN Multimedia

    OPAL was one of the four experiments installed at the LEP particle accelerator from 1989 - 2000. OPAL's central tracking system consists of (in order of increasing radius) a silicon microvertex detector, a vertex detector, a jet chamber, and z-chambers. All the tracking detectors work by observing the ionization of atoms by charged particles passing by: when the atoms are ionized, electrons are knocked out of their atomic orbitals, and are then able to move freely in the detector. These ionization electrons are detected in the dirfferent parts of the tracking system. This piece is a prototype of the jet chambers

  8. ALICE Time Projection Chamber

    CERN Multimedia

    Lippmann, C

    2013-01-01

    The Time Projection Chamber (TPC) is the main device in the ALICE 'central barrel' for the tracking and identification (PID) of charged particles. It has to cope with unprecedented densities of charges particles.

  9. Vacuum chamber 'bicone'

    CERN Multimedia

    1977-01-01

    This chamber is now in the National Museum of History and Technology, Smithsonian Institution, Washington, DC, USA, where it was exposed in an exhibit on the History of High Energy Accelerators (1977).

  10. High rate drift chambers

    Energy Technology Data Exchange (ETDEWEB)

    Christian, D.C. (Fermilab, Batavia, IL 60510 (United States)); Berisso, M.C. (Fermilab, Batavia, IL 60510 (United States)); Gutierrez, G. (Fermilab, Batavia, IL 60510 (United States)); Holmes, S.D. (Fermilab, Batavia, IL 60510 (United States)); Wehmann, A. (Fermilab, Batavia, IL 60510 (United States)); Avilez, C. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Felix, J. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Moreno, G. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Romero, M. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Sosa, M. (Instituto de Fisica, Universidad de Guanajuato, Leon, Guanajuato (Mexico)); Forbush, M. (Department of Physics, Texas A and M University, College Station, TX 77843 (United States)); Huson, F.R. (Department of Physics, Texas A and M University, College Station, TX 77843 (United States)); Wightman, J.A. (Department of Physi

    1994-06-01

    Fermilab experiment 690, a study of target dissociation reactions pp[yields]pX using an 800 GeV/c proton beam and a liquid hydrogen target, collected data in late 1991. The incident beam and 600-800 GeV/c scattered protons were measured using a system of six 6 in.x4 in. and two 15 in.x8 in. pressurized drift chambers spaced over 260 m. These chambers provided precise measurements at rates above 10 MHz (2 MHz per cm of sense wire). The measurement resolution of the smaller chambers was 90 [mu]m, and the resolution of the larger chambers was 125 [mu]m. Construction details and performance results, including radiation damage, are presented. ((orig.))

  11. Toxic Test Chambers

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Hazardous material test facility Both facilities have 16,000 cubic foot chambers, equipped with 5000 CFM CBR filter systems with an air change...

  12. Bubble chamber: antiproton annihilation

    CERN Multimedia

    1971-01-01

    These images show real particle tracks from the annihilation of an antiproton in the 80 cm Saclay liquid hydrogen bubble chamber. A negative kaon and a neutral kaon are produced in this process, as well as a positive pion. The invention of bubble chambers in 1952 revolutionized the field of particle physics, allowing real tracks left by particles to be seen and photographed by expanding liquid that had been heated to boiling point.

  13. 贝伐单抗兔眼前房注射后在眼组织的分布及其不良反应的研究%Distribution of bevacizumab in ocular tissue and its toxic effect after injection of anterior chamber

    Institute of Scientific and Technical Information of China (English)

    刘琳; 马翔; 季艳丽; 冶卓

    2011-01-01

    消失.结论 前房注射贝伐单抗1.25 mg对正常兔眼组织无明显的毒性作用和不良反应,注射后药物能快速分布于注射眼的前房角、虹膜、睫状体、脉络膜和视网膜,主要堆积在血管样组织中.%Background Bevacizumab has been widely used in the treatment of new blood vessel disease in ophthalmology.The investigation of the pharmacokinetics and safety after intracameral injection of bevacizumab can offer the basis for the management of iris neovascularization and neovascular glaucoma.Objective The present study was to observe the distribution of bevacizumab(avastin)in eye tissue and toxic effects following the injection of anterior chamber.Methods Twenty-four New Zealand albino rabbits were divided into two groups randomly.0.05 ml (1.25mg)of Bevacizumab was intracamerally injected into the left eyes in the experimental group,and a balanced salt solution of 0.05 ml was injected in the same way into the left eyes of the control group.The anterior segment of eyes and ocular fundus were examined by slit-lamp microscope and direct ophthalmoscope after injection.Intraocular pressure was measured and corneal endothelial microscopy was performed before and after the injections.Five rabbits of the two groups were sacrificed on the first day,the fourth day,the seventh day,the fourteenth day,and the thirtieth day after injection,and the eyeballs were enucleated for histopathological examination.The ultrastructure of eye tissue was observed under the transmission electron microscope on the fourth day and the thirtieth day,and then immunofluorescence staining were performed to assess the distribution of bevacizumab in the eye tissues.This experiment complied with the Regulations for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission(Version 1988).Results No abnormality in the cornea,lens,vitreous and retina was observed after the injection of bevacizumab under the slit lamp microscope and direct

  14. Sol-gel layers for ceramic microsystems application

    Science.gov (United States)

    Czok, Mateusz; Golonka, Leszek

    2016-11-01

    This paper describes research on sol-gel solutions preparation process. Utilize of a sol-gel layers in the LTCC technology for reduction of surface roughness and influence on the ceramics properties is examined and described. The influence of sol-gel layer on possible sedimentation of dyes or biological substances in channels, mixers or chambers of ceramic microfluidic structures was investigated. Moreover, properties of sol-gel coated surfaces have been precisely examined and described. Finally, positive results of conducted experiments made it possible to design and manufacture a simple microfluidic ceramic structure, with embedded protective layer of sol-gel, for fluorescence measurements.

  15. Bench measurements of the LHC injection kicker low frequency impedance properties

    CERN Document Server

    Caspers, Friedhelm; CERN. Geneva. SPS and LHC Division

    2002-01-01

    The LHC injection kicker contains a ceramic tube with inside printed metallic strips as a RF bypass in order to minimise the beam coupling impedance. These strips are capacitively coupled at one side to avoid eddy current during kicker transients. Experimentally it was found already earlier, using bench techniques, that in the region between 10 and 30 MHz certain resonances and thus peaks in the coupling impedance occur, related to the transition of the image current from the “cold conductor" to the bypass strips. The presence of these resonances has been reconfirmed as well as their properties. A practical method for reducing their influence by attaching lossy ferrite rings to the ends of the ceramic pipe is proposed and has partly been tested. As the present measurements were done on a mock-up for this RF bypass, which has limited validity towards higher frequencies, a full scale test should be repeated, once the first prototype of the 3 meter long ceramic chamber with printed bypass strips is ava...

  16. 甲壳素神经再生室注入聚乳酸-聚乙醇酸-重组人促红细胞生成素微球促进缺损周围神经的修复%Injection of polylactic acid-polyglycolic acid-recombinant human erythropoietin microspheres into chitin nerve regeneration chamber can promote sciatic nerve regeneration

    Institute of Scientific and Technical Information of China (English)

    黄亚洲; 陈清汉; 任明明

    2012-01-01

    背景:促红细胞生成素除了具有造血的作用以外,对神经系统损伤的修复也起着重要作用.目的:观察聚乳酸-聚乙醇酸-重组人促红细胞生成素微球对大鼠坐骨神经再生的作用.方法:雌性SD大鼠60只,随机分为3组.制备大鼠双侧坐骨神经缺损模型(1 cm缺损)以及可吸收甲壳素神经再生室.实验组室内注入聚乳酸-聚乙醇酸-重组人促红细胞生成素微球;对照组室内注入聚乳酸-聚乙醇酸微球;空白对照组室内注入等渗生理盐水.结果与结论:实验组再生神经的传导速度优于对照组及空白对照组,且12周优于6周,差异有显著性意义(P < 0.05).S-100 免疫组织化学及Loyez氏神经染色法显示:实验组神经纤维数量多于对照组及空白对照组,12周多于6周,差异有显著性意义(P < 0.05).结果提示聚乳酸-聚乙醇酸-重组人促红细胞生成素微球能够促进实验性坐骨神经缺损的再生和功能的恢复.%BACKGROUND: Erythropoietin (EPO) plays an important role in hematopoiesis as well as in the repair of nervous system injury. OBJECTIVE: To observe the effect of polylactic acid-polyglycolic acid-recombinant human erythropoietin microspheres on sciatic nerve regeneration. METHODS: Sixty female SD rats were randomly divided into three groups, 20 rats in each group. The bilateral sciatic nerve defect model was prepared (1 cm defect) and the absorbable chitin nerve regeneration chamber was prepared. The chambers of the rats in the experimental group were injected with polylactic acid-polyglycolic acid-recombinant human erythropoietin microspheres, chambers of the rats in the control group were injected with polylactic acid-polyglycolic acid microspheres and chambers of the rats in the blank control group were injected with normal saline in the same dose. RESULTS AND CONCLUSION: The conduction velocity of the regeneration nerve in the experimental group was better than that in the control group and

  17. Improved Rhenium Thrust Chambers

    Science.gov (United States)

    O'Dell, John Scott

    2015-01-01

    Radiation-cooled bipropellant thrust chambers are being considered for ascent/ descent engines and reaction control systems on various NASA missions and spacecraft, such as the Mars Sample Return and Orion Multi-Purpose Crew Vehicle (MPCV). Currently, iridium (Ir)-lined rhenium (Re) combustion chambers are the state of the art for in-space engines. NASA's Advanced Materials Bipropellant Rocket (AMBR) engine, a 150-lbf Ir-Re chamber produced by Plasma Processes and Aerojet Rocketdyne, recently set a hydrazine specific impulse record of 333.5 seconds. To withstand the high loads during terrestrial launch, Re chambers with improved mechanical properties are needed. Recent electrochemical forming (EL-Form"TM") results have shown considerable promise for improving Re's mechanical properties by producing a multilayered deposit composed of a tailored microstructure (i.e., Engineered Re). The Engineered Re processing techniques were optimized, and detailed characterization and mechanical properties tests were performed. The most promising techniques were selected and used to produce an Engineered Re AMBR-sized combustion chamber for testing at Aerojet Rocketdyne.

  18. Medroxyprogesterone Injection

    Science.gov (United States)

    Medroxyprogesterone intramuscular (into a muscle) injection and medroxyprogesterone subcutaneous (under the skin) injection are used to prevent pregnancy. Medroxyprogesterone subcutaneous injection is also used to treat endometriosis (a condition in which ...

  19. Pentamidine Injection

    Science.gov (United States)

    Pentamidine injection is used to treat pneumonia caused by a fungus called Pneumocystis carinii. It is in ... Pentamidine injection comes as powder to be mixed with liquid to be injected intramuscularly (into a muscle) ...

  20. DELPHI Barrel Muon Chamber Module

    CERN Multimedia

    1989-01-01

    The module was used as part of the muon identification system on the barrel of the DELPHI detector at LEP, and was in active use from 1989 to 2000. The module consists of 7 individual muons chambers arranged in 2 layers. Chambers in the upper layer are staggered by half a chamber width with respect to the lower layer. Each individual chamber is a drift chamber consisting of an anode wire, 47 microns in diameter, and a wrapped copper delay line. Each chamber provided 3 signal for each muon passing through the chamber, from which a 3D space-point could be reconstructed.

  1. The KLOE drift chamber

    Energy Technology Data Exchange (ETDEWEB)

    Adinolfi, M.; Aloisio, A.; Ambrosino, F.; Andryakov, A.; Antonelli, A.; Antonelli, M.; Anulli, F.; Bacci, C.; Bankamp, A.; Barbiellini, G.; Bellini, F.; Bencivenni, G.; Bertolucci, S.; Bini, C.; Bloise, C.; Bocci, V.; Bossi, F.; Branchini, P.; Bulychjov, S.A.; Cabibbo, G.; Calcaterra, A.; Caloi, R.; Campana, P.; Capon, G.; Carboni, G.; Cardini, A.; Casarsa, M.; Cataldi, G.; Ceradini, F.; Cervelli, F.; Cevenini, F.; Chiefari, G.; Ciambrone, P.; Conetti, S.; Conticelli, S.; Lucia, E. De; Robertis, G. De; Sangro, R. De; Simone, P. De; Zorzi, G. De; Dell' Agnello, S.; Denig, A.; Domenico, A. Di; Donato, C. Di; Falco, S. Di; Doria, A.; Drago, E.; Elia, V.; Erriquez, O.; Farilla, A.; Felici, G.; Ferrari, A.; Ferrer, M.L.; Finocchiaro, G.; Forti, C.; Franceschi, A.; Franzini, P.; Gao, M.L.; Gatti, C.; Gauzzi, P.; Giovannella, S.; Golovatyuk, V.; Gorini, E.; Grancagnolo, F.; Grandegger, W.; Graziani, E.; Guarnaccia, P.; Hagel, U.V.; Han, H.G.; Han, S.W.; Huang, X.; Incagli, M.; Ingrosso, L.; Jang, Y.Y.; Kim, W.; Kluge, W.; Kulikov, V.; Lacava, F.; Lanfranchi, G.; Lee-Franzini, J.; Lomtadze, F.; Luisi, C.; Mao, C.S.; Martemianov, M.; Matsyuk, M.; Mei, W.; Merola, L.; Messi, R.; Miscetti, S.; Moalem, A.; Moccia, S.; Moulson, M.; Mueller, S.; Murtas, F.; Napolitano, M.; Nedosekin, A.; Panareo, M.; Pacciani, L.; Pages, P.; Palutan, M.; Paoluzi, L.; Pasqualucci, E.; Passalacqua, L.; Passaseo, M.; Passeri, A.; Patera, V.; Petrolo, E.; Petrucci, G.; Picca, D.; Pirozzi, G.; Pistillo, C.; Pollack, M.; Pontecorvo, L.; Primavera, M.; Ruggieri, F.; Santangelo, P.; Santovetti, E.; Saracino, G.; Schamberger, R.D.; Schwick, C.; Sciascia, B.; Sciubba, A.; Scuri, F.; Sfiligoi, I.; Shan, J.; Silano, P.; Spadaro, T.; Spagnolo, S.; Spiriti, E.; Stanescu, C.; Tong, G.L.; Tortora, L.; Valente, E.; Valente, P. E-mail: paolo.valente@lnf.infn.it; Valeriani, B.; Venanzoni, G.; Veneziano, S.; Wu, Y.; Xie, Y.G.; Zhao, P.P.; Zhou, Y

    2001-04-01

    The tracking detector of the KLOE experiment is 4 m diameter, 3.3 m length drift chamber, designed to contain a large fraction of the decays of low-energy K{sub L} produced at the Frascati DAPHINE phi-factory. The chamber is made by a thin carbon fiber structure and operated with a helium-based gas mixture in order to minimise conversion of low-energy photons and multiple scattering inside the sensitive volume. The tracking information is provided by 58 layers of stereo wires defing 12,582 cells, 2x2 cm{sup 2} in size in the 12 innermost layers and 3x3 cm{sup 2} in the outer ones. Details of the chamber design, calibration procedure and tracking performances are presented.

  2. The KLOE drift chamber

    CERN Document Server

    Adinolfi, M; Ambrosino, F; Andryakov, A; Antonelli, A; Antonelli, M; Anulli, F; Bacci, C; Bankamp, A; Barbiellini, G; Bellini, F; Bencivenni, G; Bertolucci, Sergio; Bini, C; Bloise, C; Bocci, V; Bossi, F; Branchini, P; Bulychjov, S A; Cabibbo, G; Calcaterra, A; Caloi, R; Campana, P; Capon, G; Carboni, G; Cardini, A; Casarsa, M; Cataldi, G; Ceradini, F; Cervelli, F; Cevenini, F; Chiefari, G; Ciambrone, P; Conetti, S; Conticelli, S; Lucia, E D; Robertis, G D; Sangro, R D; Simone, P D; Zorzi, G D; Dell'Agnello, S; Denig, A; Domenico, A D; Donato, C D; Falco, S D; Doria, A; Drago, E; Elia, V; Erriquez, O; Farilla, A; Felici, G; Ferrari, A; Ferrer, M L; Finocchiaro, G; Forti, C; Franceschi, A; Franzini, P; Gao, M L; Gatti, C; Gauzzi, P; Giovannella, S; Golovatyuk, V; Gorini, E; Grancagnolo, F; Grandegger, W; Graziani, E; Guarnaccia, P; Von Hagel, U; Han, H G; Han, S W; Huang, X; Incagli, M; Ingrosso, L; Jang, Y Y; Kim, W; Kluge, W; Kulikov, V; Lacava, F; Lanfranchi, G; Lee-Franzini, J; Lomtadze, F; Luisi, C; Mao Chen Sheng; Martemyanov, M; Matsyuk, M; Mei, W; Merola, L; Messi, R; Miscetti, S; Moalem, A; Moccia, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nedosekin, A; Panareo, M; Pacciani, L; Pagès, P; Palutan, M; Paoluzi, L; Pasqualucci, E; Passalacqua, L; Passaseo, M; Passeri, A; Patera, V; Petrolo, E; Petrucci, Guido; Picca, D; Pirozzi, G; Pistillo, C; Pollack, M; Pontecorvo, L; Primavera, M; Ruggieri, F; Santangelo, P; Santovetti, E; Saracino, G; Schamberger, R D; Schwick, C; Sciascia, B; Sciubba, A; Scuri, F; Sfiligoi, I; Shan, J; Silano, P; Spadaro, T; Spagnolo, S; Spiriti, E; Stanescu, C; Tong, G L; Tortora, L; Valente, E; Valente, P; Valeriani, B; Venanzoni, G; Veneziano, Stefano; Wu, Y; Xie, Y G; Zhao, P P; Zhou, Y

    2001-01-01

    The tracking detector of the KLOE experiment is 4 m diameter, 3.3 m length drift chamber, designed to contain a large fraction of the decays of low-energy K sub L produced at the Frascati DAPHINE phi-factory. The chamber is made by a thin carbon fiber structure and operated with a helium-based gas mixture in order to minimise conversion of low-energy photons and multiple scattering inside the sensitive volume. The tracking information is provided by 58 layers of stereo wires defing 12,582 cells, 2x2 cm sup 2 in size in the 12 innermost layers and 3x3 cm sup 2 in the outer ones. Details of the chamber design, calibration procedure and tracking performances are presented.

  3. MODELING OF FUEL SPRAY CHARACTERISTICS AND DIESEL COMBUSTION CHAMBER PARAMETERS

    Directory of Open Access Journals (Sweden)

    G. M. Kukharonak

    2011-01-01

    Full Text Available The computer model for coordination of fuel spray characteristics with diesel combustion chamber parameters has been created in the paper.  The model allows to observe fuel sprays  develоpment in diesel cylinder at any moment of injection, to calculate characteristics of fuel sprays with due account of a shape and dimensions of a combustion chamber, timely to change fuel injection characteristics and supercharging parameters, shape and dimensions of a combustion chamber. Moreover the computer model permits to determine parameters of holes in an injector nozzle that provides the required fuel sprays characteristics at the stage of designing a diesel engine. Combustion chamber parameters for 4ЧН11/12.5 diesel engine have been determined in the paper.

  4. micro strip gas chamber

    CERN Multimedia

    1998-01-01

    About 16 000 Micro Strip Gas Chambers like this one will be used in the CMS tracking detector. They will measure the tracks of charged particles to a hundredth of a millimetre precision in the region near the collision point where the density of particles is very high. Each chamber is filled with a gas mixture of argon and dimethyl ether. Charged particles passing through ionise the gas, knocking out electrons which are collected on the aluminium strips visible under the microscope. Such detectors are being used in radiography. They give higher resolution imaging and reduce the required dose of radiation.

  5. Charpak hemispherical wire chamber

    CERN Multimedia

    1970-01-01

    pieces. Mesures are of the largest one. Multi-wire detectors contain layers of positively and negatively charged wires enclosed in a chamber full of gas. A charged particle passing through the chamber knocks negatively charged electrons out of atoms in the gas, leaving behind positive ions. The electrons are pulled towards the positively charged wires. They collide with other atoms on the way, producing an avalanche of electrons and ions. The movement of these electrons and ions induces an electric pulse in the wires which is collected by fast electronics. The size of the pulse is proportional to the energy loss of the original particle.

  6. Embedded computer controlled premixing inline injection system for air-assisted variable-rate sprayers

    Science.gov (United States)

    Improvements to reduce chemical waste and environmental pollution for variable-rate sprayers used in orchards and ornamental nurseries require inline injection techniques. A microprocessor controlled premixing inline injection system implementing a ceramic piston chemical metering pump and two small...

  7. Forecasting magma-chamber rupture at Santorini volcano, Greece

    OpenAIRE

    John Browning; Kyriaki Drymoni; Agust Gudmundsson

    2015-01-01

    How much magma needs to be added to a shallow magma chamber to cause rupture, dyke injection, and a potential eruption? Models that yield reliable answers to this question are needed in order to facilitate eruption forecasting. Development of a long-lived shallow magma chamber requires periodic influx of magmas from a parental body at depth. This redistribution process does not necessarily cause an eruption but produces a net volume change that can be measured geodetically by inversion techni...

  8. Heavy liquid bubble chamber

    CERN Multimedia

    1965-01-01

    The CERN Heavy liquid bubble chamber being installed in the north experimental hall at the PS. On the left, the 1180 litre body; in the centre the magnet, which can produce a field of 26 800 gauss; on the right the expansion mechanism.

  9. OPAL Muon Chamber

    CERN Multimedia

    OPAL was one of the 4 experiments installed at the LEP particle accelerator from 1989 to 2000. This is a slice of the outermost layer of OPAL : the muon chambers. This outside layer detects particles which are not stopped by the previous layers. These are mostly muons.

  10. LEP Vacuum Chamber

    CERN Multimedia

    1983-01-01

    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.

  11. Scanning bubble chamber pictures

    CERN Multimedia

    1974-01-01

    These were taken at the 2 m hydrogen bubble chamber. The photo shows an early Shiva system where the pre-measurements needed to qualify the event were done manually (cf photo 7408136X). The scanning tables were located in bld. 12. Gilberte Saulmier sits on foreground, Inge Arents at centre.

  12. LEP vacuum chamber, prototype

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    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.

  13. Secondary emission gas chamber

    CERN Document Server

    In'shakov, V; Skvortsov, V

    2014-01-01

    For a hadron calorimeter active element there is considered a gaseous secondary emis-sion detector (150 micron gap, 50 kV/cm). Such one-stage parallel plate chamber must be a radiation hard, fast and simple. A model of such detector has been produced, tested and some characteristics are presented.

  14. Ceramic Matrix Composites .

    Directory of Open Access Journals (Sweden)

    J. Mukerji

    1993-10-01

    Full Text Available The present state of the knowledge of ceramic-matrix composites have been reviewed. The fracture toughness of present structural ceramics are not enough to permit design of high performance machines with ceramic parts. They also fail by catastrophic brittle fracture. It is generally believed that further improvement of fracture toughness is only possible by making composites of ceramics with ceramic fibre, particulate or platelets. Only ceramic-matrix composites capable of working above 1000 degree centigrade has been dealt with keeping reinforced plastics and metal-reinforced ceramics outside the purview. The author has discussed the basic mechanisms of toughening and fabrication of composites and the difficulties involved. Properties of available fibres and whiskers have been given. The best results obtained so far have been indicated. The limitations of improvement in properties of ceramic-matrix composites have been discussed.

  15. Ceramic Laser Materials

    Directory of Open Access Journals (Sweden)

    Guillermo Villalobos

    2012-02-01

    Full Text Available Ceramic laser materials have come a long way since the first demonstration of lasing in 1964. Improvements in powder synthesis and ceramic sintering as well as novel ideas have led to notable achievements. These include the first Nd:yttrium aluminum garnet (YAG ceramic laser in 1995, breaking the 1 KW mark in 2002 and then the remarkable demonstration of more than 100 KW output power from a YAG ceramic laser system in 2009. Additional developments have included highly doped microchip lasers, ultrashort pulse lasers, novel materials such as sesquioxides, fluoride ceramic lasers, selenide ceramic lasers in the 2 to 3 μm region, composite ceramic lasers for better thermal management, and single crystal lasers derived from polycrystalline ceramics. This paper highlights some of these notable achievements.

  16. Ceramic Laser Materials

    Science.gov (United States)

    Sanghera, Jasbinder; Kim, Woohong; Villalobos, Guillermo; Shaw, Brandon; Baker, Colin; Frantz, Jesse; Sadowski, Bryan; Aggarwal, Ishwar

    2012-01-01

    Ceramic laser materials have come a long way since the first demonstration of lasing in 1964. Improvements in powder synthesis and ceramic sintering as well as novel ideas have led to notable achievements. These include the first Nd:yttrium aluminum garnet (YAG) ceramic laser in 1995, breaking the 1 KW mark in 2002 and then the remarkable demonstration of more than 100 KW output power from a YAG ceramic laser system in 2009. Additional developments have included highly doped microchip lasers, ultrashort pulse lasers, novel materials such as sesquioxides, fluoride ceramic lasers, selenide ceramic lasers in the 2 to 3 μm region, composite ceramic lasers for better thermal management, and single crystal lasers derived from polycrystalline ceramics. This paper highlights some of these notable achievements. PMID:28817044

  17. New Materials for Vacuum Chambers in High Energy Physics

    CERN Document Server

    Garion, Cédric

    2014-01-01

    Vacuum chambers must fulfil ultra-high vacuum requirements while withstanding thermo-mechanical loads. This is particularly true in high energy particle accelerator where interactions of particles with matter may induce thermal load, material activation, background… The choice of the material of the vacuum chamber is crucial for the final application. Metals such as stainless steel, copper and aluminium are usually used. Even with outstanding mechanical and physical properties, beryllium is used for very specific applications because of its cost and toxicity.Ceramics such as alumina are usually used for fast magnet vacuum chambers. With the next generation of high energy physics accelerator generation such as CLIC and TLEP, the problematic of high cyclic thermal load induced by synchrotron radiation is raised. This paper aims at defining some figures of merit of different materials with respect to several load scenarios and presents briefly their vacuum compatibility.

  18. Ceramic art in sculpture

    OpenAIRE

    Rokavec, Eva

    2014-01-01

    Diploma seminar speaks of ceramics as a field of artistic expression and not just as pottery craft. I presented short overview of developing ceramic sculpture and its changing role. Clay inspires design and touch more than other sculpture media. It starts as early as in prehistory. Although it sometimes seems that was sculptural ceramics neglected in art history overview, it was not so in actual praxis. There is a rich tradition of ceramics in the East and also in Europe during the renaissanc...

  19. Ceramic to metal seal

    Energy Technology Data Exchange (ETDEWEB)

    Snow, Gary S. (Albuquerque, NM); Wilcox, Paul D. (Albuquerque, NM)

    1976-01-01

    Providing a high strength, hermetic ceramic to metal seal by essentially heating a wire-like metal gasket and a ceramic member, which have been chemically cleaned, while simultaneously deforming from about 50 to 95 percent the metal gasket against the ceramic member at a temperature of about 30 to 75 percent of the melting temperature of the metal gasket.

  20. Light element ceramics

    OpenAIRE

    Rao, KJ; Varma, KBR; Raju, AR

    1988-01-01

    An overview of a few structually important light element ceramics is presented. Included in the overview are silicon nitide, sialon, aluminium nitride, boron carbide and silicon carbide. Methods of preparation, characterization and industrial applications of these ceramics are summarized. Mechanical properties, industrial production techniques and principal uses of these ceramics are emphasized.

  1. Isolation of Drosophila egg chambers for imaging.

    Science.gov (United States)

    Parton, Richard M; Vallés, Ana Maria; Dobbie, Ian M; Davis, Ilan

    2010-04-01

    The fruit fly Drosophila melanogaster is an important model for basic research into the molecular mechanisms underlying cell function and development, as well as a major biomedical research tool. A significant advantage of Drosophila is the ability to apply live cell imaging to a variety of living tissues that can be dissected and imaged in vivo, ex vivo, or in vitro. Drosophila egg chambers, for example, have proven to be a useful model system for studying border cell migration, Golgi unit transport, the rapid movement of mRNA and protein particles, and the role of microtubules in meiosis and oocyte differentiation. A crucial first step before imaging is preparation of the experimental material to ensure physiological relevance and to achieve the best conditions for image quality. Early- to mid-stage egg chambers cannot be mounted in an aqueous-based medium, because this causes a change in microtubule organization and follicle cell morphology. Such egg chambers survive better in Halocarbon oil, which allows free diffusion of oxygen, has low viscosity, and thus prevents dehydration and hypoxia. With a refractive index similar to glycerol, Halocarbon oil also has good optical properties for imaging. It also provides a good environment for injection and is particularly useful for long-term imaging of embryos. However, unlike with aqueous solutions, changes in the medium are not possible. This protocol describes the isolation of Drosophila egg chambers.

  2. Thin film ceramic thermocouples

    Science.gov (United States)

    Gregory, Otto (Inventor); Fralick, Gustave (Inventor); Wrbanek, John (Inventor); You, Tao (Inventor)

    2011-01-01

    A thin film ceramic thermocouple (10) having two ceramic thermocouple (12, 14) that are in contact with each other in at least on point to form a junction, and wherein each element was prepared in a different oxygen/nitrogen/argon plasma. Since each element is prepared under different plasma conditions, they have different electrical conductivity and different charge carrier concentration. The thin film thermocouple (10) can be transparent. A versatile ceramic sensor system having an RTD heat flux sensor can be combined with a thermocouple and a strain sensor to yield a multifunctional ceramic sensor array. The transparent ceramic temperature sensor that could ultimately be used for calibration of optical sensors.

  3. Forming of superplastic ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Lesuer, D.R.; Wadsworth, J.; Nieh, T.G.

    1994-05-01

    Superplasticity in ceramics has now advanced to the stage that technologically viable superplastic deformation processing can be performed. In this paper, examples of superplastic forming and diffusion bonding of ceramic components are given. Recent work in biaxial gas-pressure forming of several ceramics is provided. These include yttria-stabilized, tetragonal zirconia (YTZP), a 20% alumina/YTZP composite, and silicon. In addition, the concurrent superplastic forming and diffusion bonding of a hybrid ceramic-metal structure are presented. These forming processes offer technological advantages of greater dimensional control and increased variety and complexity of shapes than is possible with conventional ceramic shaping technology.

  4. Ceramic gas turbine shroud

    Science.gov (United States)

    Shi, Jun; Green, Kevin E.

    2014-07-22

    An example gas turbine engine shroud includes a first annular ceramic wall having an inner side for resisting high temperature turbine engine gasses and an outer side with a plurality of radial slots. A second annular metallic wall is positioned radially outwardly of and enclosing the first annular ceramic wall and has a plurality of tabs in communication with the slot of the first annular ceramic wall. The tabs of the second annular metallic wall and slots of the first annular ceramic wall are in communication such that the first annular ceramic wall and second annular metallic wall are affixed.

  5. Creep in ceramics

    CERN Document Server

    Pelleg, Joshua

    2017-01-01

    This textbook is one of its kind, since there are no other books on Creep in Ceramics. The book consist of two parts: A and B. In part A general knowledge of creep in ceramics is considered, while part B specifies creep in technologically important ceramics. Part B covers creep in oxide ceramics, carnides and nitrides. While covering all relevant information regarding raw materials and characterization of creep in ceramics, the book also summarizes most recent innovations and developments in this field as a result of extensive literature search.

  6. Anechoic Radio Frequency Test Chamber

    Data.gov (United States)

    Federal Laboratory Consortium — This chamber is used for characterization test of such systems as communications gear, tanks, radar, missiles, and helicopters. The dimensions of the chamber are 114...

  7. The influence of methods of injection moulding and isostatic pressing on structural ceramics performance Influência de métodos de moldagem por injeção e prensagem isostática no desempenho de cerâmicas estruturais

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Fortulan

    1998-10-01

    Full Text Available Advanced ceramics for structural applications are present in engineering parts subjected to complex solicitations. Such unique combination of properties makes these ceramics the unique solution for material selection in special cases. However a material selection cannot be made independently of the choice of manufacturing processes, shape and cost. The determination of a methodology for the evaluation of the sintered ceramic parts reliability is as important as the selection and processing techniques. This work presents the recent trends in the structural advanced ceramics application, the cold forming isostatic pressing and injection processes molding, the elaboration of a methodology for the performance evaluation and choice of forming processes related with the mechanical properties, microstructure and unlubricated sliding wear.Cerâmicas avançadas para aplicações estruturais estão presentes em componentes de engenharia submetidos a solicitações complexas. Tal combinação única de propriedades torna essas cerâmicas solução sem paralelo para seleção de materiais em casos especiais. Uma seleção de materiais não pode contudo ser feita independentemente da escolha de processos de fabricação, forma e custo. A determinação de uma metodologia para a avaliação do grau de confiança dos componentes cerâmicos sinterizados é tão importante quanto as técnicas de seleção e de processamento. Este trabalho apresenta as tendências recentes na aplicação de cerâmicas estruturais avançadas, na conformação a frio por prensagem isostática e moldagem por processos de injeção, a elaboração de uma metologia para avaliação de desempenho e escolha de processos de corformação relacionados com propriedades mecânicas, microestrutura e desgaste por atrito sem lubrificante.

  8. Liquid fuel injection elements for rocket engines

    Science.gov (United States)

    Cox, George B., Jr. (Inventor)

    1993-01-01

    Thrust chambers for liquid propellant rocket engines include three principal components. One of these components is an injector which contains a plurality of injection elements to meter the flow of propellants at a predetermined rate, and fuel to oxidizer mixture ratio, to introduce the mixture into the combustion chamber, and to cause them to be atomized within the combustion chamber so that even combustion takes place. Evolving from these injectors are tube injectors. These tube injectors have injection elements for injecting the oxidizer into the combustion chamber. The oxidizer and fuel must be metered at predetermined rates and mixture ratios in order to mix them within the combustion chamber so that combustion takes place smoothly and completely. Hence tube injectors are subject to improvement. An injection element for a liquid propellant rocket engine of the bipropellant type is provided which includes tangential fuel metering orifices, and a plurality of oxidizer tube injection elements whose injection tubes are also provided with tangential oxidizer entry slots and internal reed valves.

  9. Innovative Drug Injection via Laser Induced Plasma

    Science.gov (United States)

    Han, Tae-hee; Yoh, Jack J.

    2010-10-01

    A laser based needle-free liquid drug injection device has been developed. A laser beam is focused inside the liquid contained in the rubber chamber of micro scale. The focused laser beam causes explosive bubble growth and the sudden volume increase in a sealed chamber drives a microjet of liquid drug through the micronozzle. The exit diameter of the nozzle is 125 um and the injected microjet reaches an average velocity of 264 m/s. This device adds the time-varying feature of microjet to the current state of liquid injection for drug delivery.

  10. Doripenem Injection

    Science.gov (United States)

    ... injection is in a class of medications called carbapenem antibiotics. It works by killing bacteria.Antibiotics such ... if you are allergic to doripenem injection; other carbapenem antibiotics such as imipenem/cilastatin (Primaxin) or meropenem ( ...

  11. Methotrexate Injection

    Science.gov (United States)

    Methotrexate injection is used alone or in combination with other medications to treat gestational trophoblastic tumors (a ... in bones) after surgery to remove the tumor. Methotrexate injection is also used to treat severe psoriasis ( ...

  12. Bendamustine Injection

    Science.gov (United States)

    Bendamustine injection is used to treat chronic lymphocytic leukemia (CLL; a type of cancer of the white ... injection. You should use birth control to prevent pregnancy in yourself or your partner during your treatment ...

  13. Caspofungin Injection

    Science.gov (United States)

    Caspofungin injection is used in adults and children 3 months of age and older to treat yeast ... people with a weakened ability to fight infection. Caspofungin injection is in a class of antifungal medications ...

  14. Temozolomide Injection

    Science.gov (United States)

    Temozolomide is used to treat certain types of brain tumors. Temozolomide is in a class of medications called alkylating ... Temozolomide injection comes as a powder to be added to fluid and injected over 90 minutes intravenously ( ...

  15. Pembrolizumab Injection

    Science.gov (United States)

    Pembrolizumab injection is used to treat melanoma (a type of skin cancer) that cannot be treated with ... who have a specific type of melanoma tumor. Pembrolizumab injection is also used to treat a certain ...

  16. Lacosamide Injection

    Science.gov (United States)

    ... injection is in a class of medications called anticonvulsants. It works by decreasing abnormal electrical activity in ... older (about 1 in 500 people) who took anticonvulsants like lacosamide injection to treat various conditions during ...

  17. Midazolam Injection

    Science.gov (United States)

    ... injection is in a class of medications called benzodiazepines. It works by slowing activity in the brain ... breast-feeding.talk to your doctor about the risks and benefits of receiving midazolam injection if you ...

  18. Doxycycline Injection

    Science.gov (United States)

    Doxycycline injection is used to treat or prevent bacterial infections, including pneumonia and other respiratory tract infections. ... certain skin, genital, intestine, and urinary system infections. Doxycycline injection may be used to treat or prevent ...

  19. Paclitaxel Injection

    Science.gov (United States)

    ... with other medications. Paclitaxel injection manufactured with polyoxyethylated castor oil is used to treat ovarian cancer (cancer that ... cancer, and lung cancer. Paclitaxel injection with polyoxyethylated castor oil is also used to treat Kaposi's sarcoma (a ...

  20. Etanercept Injection

    Science.gov (United States)

    ... will be using the prefilled syringe or automatic injection device, tell your doctor if you or the person who will be injecting the medication for you are allergic to rubber or latex.tell your doctor and pharmacist what ...

  1. Cyclosporine Injection

    Science.gov (United States)

    Cyclosporine injection is used with other medications to prevent transplant rejection (attack of the transplanted organ by ... who have received kidney, liver, and heart transplants. Cyclosporine injection should only be used to treat people ...

  2. Estrogen Injection

    Science.gov (United States)

    The estradiol cypionate and estradiol valerate forms of estrogen injection are used to treat hot flushes (hot ... should consider a different treatment. These forms of estrogen injection are also sometimes used to treat the ...

  3. Cefotaxime Injection

    Science.gov (United States)

    Cefotaxime injection is used to treat certain infections caused by bacteria including pneumonia and other lower respiratory ... skin, blood, bone, joint, and urinary tract infections. Cefotaxime injection may also be used before surgery, and ...

  4. Microstructure and Mechanical Properties of Alumina Powder Coatings by a New Multi-Chamber Detonation Sprayer

    Science.gov (United States)

    Prozorova, M. S.; Kovaleva, M. G.; Arseenko, M. Yu.; Yapryntsev, M. N.; Tyurin, Yu. N.; Kolisnichenko, O. V.; Vasilik, N. Ya.; Sirota, V. V.; Pavlenko, I. A.; Mamunin, K. N.

    2016-11-01

    The dense ceramic coatings based on alumina with hardness of 1100±25 HV0.3 and porosity of less than 1% have been prepared by multi-chamber detonation sprayer (MCDS) with a barrel length of 500mm. The intermetallic compound of type FeAl was revealed in the area of the coating that adjoins the substrate.

  5. Resin Viscosity Influence on Fiber Compaction in Tapered Resin Injection Pultrusion Manufacturing

    Science.gov (United States)

    Masuram, N. B.; Roux, J. A.; Jeswani, A. L.

    2017-08-01

    Viscosity of the liquid resin effects the chemical and mechanical properties of the pultruded composite. In resin injection pultrusion manufacturing the liquid resin is injected into a specially designed tapered injection chamber through the injection slots present on top and bottom of the chamber. The resin is injected at a pressure so as to completely wetout the fiber reinforcements inside the tapered injection chamber. As the resin penetrates through the fibers, the resin also pushes the fibers away from the wall towards the center of chamber causing compaction of the fiber reinforcements. The fibers are squeezed together due to compaction, making resin penetration more difficult; thus higher resin injection pressures are required to efficaciously penetrate through the compacted fibers and achieve complete wetout. The impact of resin viscosity on resin flow, fiber compaction, wetout and on the final product is further discussed. Injection chamber design predominantly effects the resin flow inside the chamber and the minimum injection pressure required to completely wet the fibers. Therefore, a desirable injection chamber design is such that wetout occurs at lower injection pressures and at low internal pressures inside the injection chamber.

  6. Ustekinumab Injection

    Science.gov (United States)

    ... Do not inject into an area where the skin is tender, bruised, red, or hard or where you have scars or stretch marks.Your doctor or pharmacist will ... injection.you should know that ustekinumab injection may decrease your ability ... new or changing skin lesions, minor infections (such as open cuts or ...

  7. Ranitidine Injection

    Science.gov (United States)

    Ranitidine injection comes as a solution (liquid) to be mixed with another fluid and injected intravenously (into a vein) over 5 to 20 minutes. Ranitidine may also be injected into a muscle. It is usually given every 6 to 8 hours, but may also be given ...

  8. Vacuum Chambers for LEP sections

    CERN Multimedia

    1983-01-01

    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.

  9. Multi-anode ionization chamber

    Energy Technology Data Exchange (ETDEWEB)

    Bolotnikov, Aleksey E. (South Setauket, NY); Smith, Graham (Port Jefferson, NY); Mahler, George J. (Rocky Point, NY); Vanier, Peter E. (Setauket, NY)

    2010-12-28

    The present invention includes a high-energy detector having a cathode chamber, a support member, and anode segments. The cathode chamber extends along a longitudinal axis. The support member is fixed within the cathode chamber and extends from the first end of the cathode chamber to the second end of the cathode chamber. The anode segments are supported by the support member and are spaced along the longitudinal surface of the support member. The anode segments are configured to generate at least a first electrical signal in response to electrons impinging thereon.

  10. Forecasting magma-chamber rupture at Santorini volcano, Greece

    Science.gov (United States)

    Browning, John; Drymoni, Kyriaki; Gudmundsson, Agust

    2015-10-01

    How much magma needs to be added to a shallow magma chamber to cause rupture, dyke injection, and a potential eruption? Models that yield reliable answers to this question are needed in order to facilitate eruption forecasting. Development of a long-lived shallow magma chamber requires periodic influx of magmas from a parental body at depth. This redistribution process does not necessarily cause an eruption but produces a net volume change that can be measured geodetically by inversion techniques. Using continuum-mechanics and fracture-mechanics principles, we calculate the amount of magma contained at shallow depth beneath Santorini volcano, Greece. We demonstrate through structural analysis of dykes exposed within the Santorini caldera, previously published data on the volume of recent eruptions, and geodetic measurements of the 2011-2012 unrest period, that the measured 0.02% increase in volume of Santorini’s shallow magma chamber was associated with magmatic excess pressure increase of around 1.1 MPa. This excess pressure was high enough to bring the chamber roof close to rupture and dyke injection. For volcanoes with known typical extrusion and intrusion (dyke) volumes, the new methodology presented here makes it possible to forecast the conditions for magma-chamber failure and dyke injection at any geodetically well-monitored volcano.

  11. Evaluation of Impinging Stream Vortex Chamber Concepts for Liquid Rocket Engine Applications

    Science.gov (United States)

    Trinh, Huu P.; Bullard, Brad; Kopicz, Charles; Michaels, Scott

    2002-01-01

    To pursue technology developments for future launch vehicles, NASA/Marshall Space Flight Center (MSFC) is examining vortex chamber concepts for liquid rocket engine applications. Past studies indicated that the vortex chamber schemes potentially have a number of advantages over conventional chamber methods. Due to the nature of the vortex flow, relatively cooler propellant streams tend to flow along the chamber wall. Hence, the thruster chamber can be operated without the need of any cooling techniques. This vortex flow also creates strong turbulence, which promotes the propellant mixing process. Consequently, the subject chamber concepts not only offer system simplicity, but also enhance the combustion performance. Test results have shown that chamber performance is markedly high even at a low chamber length-to-diameter ratio (LD). This incentive can be translated to a convenience in the thrust chamber packaging. Variations of the vortex chamber concepts have been introduced in the past few decades. These investigations include an ongoing work at Orbital Technologies Corporation (ORBITEC). By injecting the oxidizer tangentially at the chamber convergence and fuel axially at the chamber head end, Knuth et al. were able to keep the wall relatively cold. A recent investigation of the low L/D vortex chamber concept for gel propellants was conducted by Michaels. He used both triplet (two oxidizer orifices and one fuel orifice) and unlike impinging schemes to inject propellants tangentially along the chamber wall. Michaels called the subject injection scheme an Impinging Stream Vortex Chamber (ISVC). His preliminary tests showed that high performance, with an Isp efficiency of 9295, can be obtained. MSFC and the U. S. Army are jointly investigating an application of the ISVC concept for the cryogenic oxygen/hydrocarbon propellant system. This vortex chamber concept is currently tested with gel propellants at AMCOM at Redstone Arsenal, Alabama. A version of this concept

  12. The friction and wear of ceramic/ceramic and ceramic/metal combinations in sliding contact

    Science.gov (United States)

    Sliney, Harold E.; Dellacorte, Christopher

    1994-01-01

    The tribological characteristics of ceramics sliding on ceramics are compared to those of ceramics sliding on a nickel-based turbine alloy. The friction and wear of oxide ceramics and silicon-based ceramics in air at temperatures from room ambient to 900 C (in a few cases to 1200 C) were measured for a hemispherically-tipped pin on a flat sliding contact geometry. In general, especially at high temperature, friction and wear were lower for ceramic/metal combinations than for ceramic/ceramic combinations. The better tribological performance for ceramic/metal combinations is attributed primarily to the lubricious nature of the oxidized surface of the metal.

  13. Moldagem por injeção de pós cerâmicos: remoção da parafina e do polipropileno utilizados como veículo orgânico Ceramic injection molding: removal of pafafin and polypropylene used as organic binder

    Directory of Open Access Journals (Sweden)

    Ricardo V. B. Oliveira

    2004-09-01

    Full Text Available A moldagem por injeção de pós cerâmicos tem se tornado um processo altamente atrativo por aliar a versatilidade e a produtividade da moldagem por injeção convencional às propriedades inerentes aos materiais cerâmicos. A remoção do ligante, usado como veículo orgânico nesse processo, é uma das etapas críticas para a produção de peças cerâmicas sem defeitos. Neste trabalho avaliou-se a influência da geometria das peças injetadas na remoção do ligante, tanto por imersão em solvente como por decomposição térmica. Alumina em pó foi misturada fisicamente a um ligante composto por polipropileno [PP], parafina [PW] e ácido esteárico [AE]. As peças com diferentes geometrias foram mantidas imersas em hexano, secas sob vácuo e acompanhada a variação de massa devido à solubilização do PW e AE. A determinação da porosidade das peças, realizada por meio das isotermas de adsorção/desorção de nitrogênio, mostrou um aumento de porosidade de 0,5% volume para aproximadamente 20% volume após a imersão em solvente. A remoção térmica do PP remanescente produziu hidrocarbonetos alifáticos e compostos insaturados, determinados e quantificados por espectroscopia de infravermelho, que permearam a estrutura porosa da peça. A geometria das peças tem grande influência na remoção do ligante, podendo afetar não só a qualidade do produto final, mas também as etapas subseqüentes do processo.Powder injection molding [PIM] has become highly attractive as it combines the versatility and productivity of conventional injection molding processes with the intrinsic properties of metallic and ceramic materials. The removal of organic binder, used as vehicles during the process, is one of the most critical stages in the production of ceramic devices in this process. In this work, the influence from the geometry of the injected part on the removal of the organic binder was evaluated for both solvent immersion and thermal

  14. Council Chamber exhibition

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    To complete the revamp of CERN’s Council Chamber, a new exhibition is being installed just in time for the June Council meetings.   Panels will showcase highlights of CERN’s history, using some of the content prepared for the exhibitions marking 50 years of the PS, which were displayed in the main building last November. The previous photo exhibition in the Council Chamber stopped at the 1970s. To avoid the new panels becoming quickly out of date, photos are grouped together around specific infrastructures, rather than following a classic time-line. “We have put the focus on the accelerators – the world-class facilities that CERN has been offering researchers over the years, from the well-known large colliders to the lesser-known smaller facilities,” says Emma Sanders, who worked on the content. The new exhibition will be featured in a future issue of the Bulletin with photos and an interview with Fabienne Marcastel, designer of the exhibit...

  15. Analyses of fine paste ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Sabloff, J A [ed.

    1980-01-01

    Four chapters are included: history of Brookhaven fine paste ceramics project, chemical and mathematical procedures employed in Mayan fine paste ceramics project, and compositional and archaeological perspectives on the Mayan fine paste ceramics. (DLC)

  16. Ceramic laser materials

    Science.gov (United States)

    Ikesue, Akio; Aung, Yan Lin

    2008-12-01

    The word 'ceramics' is derived from the Greek keramos, meaning pottery and porcelain. The opaque and translucent cement and clay often used in tableware are not appropriate for optical applications because of the high content of optical scattering sources, that is, defects. Recently, scientists have shown that by eliminating the defects, a new, refined ceramic material - polycrystalline ceramic - can be produced. This advanced ceramic material offers practical laser generation and is anticipated to be a highly attractive alternative to conventional glass and single-crystal laser technologies in the future. Here we review the history of the development of ceramic lasers, the principle of laser generation based on this material, some typical results achieved with ceramic lasers so far, and discuss the potential future outlook for the field.

  17. Laser Ceramics Sintering by Millimeter-Wave Heating

    Science.gov (United States)

    Egorov, S. V.; Bykov, Yu. V.; Eremeev, A. G.; Sorokin, A. A.

    2014-01-01

    Prospects for using microwave radiation to sinter optically transparent ceramics are stipulated by the absence of the heaters and screens contaminating the sintered material and the presence of the inverse temperature distribution in the product, which allows one to fabricate maximum-density ceramics. In this work, we present the results of studying the process of producing optically transparent Yb:YAG and Yb:(LaY)2O3 ceramics when the samples are sintered in the chamber of a gyrotron complex operated at a frequency of 24 GHz. The various-composition samples were manufactured by compaction of a mixture of commercially available powders (Yb:YAG ceramics) and the powders prepared by the self-propagating high-temperature synthesis (Yb:(LaY)2O3 ceramics). The sintering temperatures were varied in the interval 1700-1900°C, the sintering time was varied from 2 to 20 h, and the residual-air pressure in the working chamber was 10 Pa. Lasing was obtained for the samples of both compositions.

  18. Antibacterial ceramic for sandbox. Sunabayo kokin ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, K. (Ishizuka Glass Co. Ltd. Nagoya (Japan))

    1993-10-01

    Sands in sandboxes in parks have been called into question of being contaminated by colon bacilli and spawns from ascarides. This paper introduces an antibacterial ceramic for sandbox developed as a new material effective to help reduce the contamination. The ceramic uses natural sand as the main raw material, which is added with borax and silver to contain silver ions that have bacteria and fungus resistance and deodorizing effect. The ceramic has an average grain size ranging from 0.5 mm to 0.7 mm, and is so devised as to match specific gravity, grain size and shape of the sand, hence no separation and segregation can occur. The result of weatherability and antibacterial strength tests on sand for a sandbox mixed with the ceramic at 1% suggests that its efficacy lasts for about three years. Its actual use is under observation. Its efficacy has been verified in a test that measures a survival factor of spawns from dog ascardides contacted with aqueous solution containing the ceramic at 1%. Safety and sanitation tests have proved the ceramic a highly safe product that conforms to the food sanitation law. 5 refs., 3 figs., 3 tabs.

  19. Continuous Fiber Ceramic Composites

    Energy Technology Data Exchange (ETDEWEB)

    None

    2002-09-01

    Fiber-reinforced ceramic composites demonstrate the high-temperature stability of ceramics--with an increased fracture toughness resulting from the fiber reinforcement of the composite. The material optimization performed under the continuous fiber ceramic composites (CFCC) included a series of systematic optimizations. The overall goals were to define the processing window, to increase the robustinous of the process, to increase process yield while reducing costs, and to define the complexity of parts that could be fabricated.

  20. Method of injecting fluid propellants into a rocket combustion chamber

    Science.gov (United States)

    Schneider, Steven J. (Inventor)

    1991-01-01

    A rocket injector is provided with multiple sets of manifolds for supplying propellants to injector elements. Sensors transmit the temperatures of the propellants to a suitable controller which is operably connected to valves between these manifolds and propellant storage tanks. Additional valves are opened to furnish propellants to more of the manifolds when cryogenic propellant temperatures are sensed. Only a portion of the valves are opened to furnish propellants to some of the manifolds when lower temperatures are sensed.

  1. Defect production in ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Zinkle, S.J. [Oak Ridge National Lab., TN (United States); Kinoshita, C. [Kyushu Univ. (Japan)

    1997-08-01

    A review is given of several important defect production and accumulation parameters for irradiated ceramics. Materials covered in this review include alumina, magnesia, spinel silicon carbide, silicon nitride, aluminum nitride and diamond. Whereas threshold displacement energies for many ceramics are known within a reasonable level of uncertainty (with notable exceptions being AIN and Si{sub 3}N{sub 4}), relatively little information exists on the equally important parameters of surviving defect fraction (defect production efficiency) and point defect migration energies for most ceramics. Very little fundamental displacement damage information is available for nitride ceramics. The role of subthreshold irradiation on defect migration and microstructural evolution is also briefly discussed.

  2. Posterior Chamber Hemorrhage during Fluorescein Angiography

    Directory of Open Access Journals (Sweden)

    Manuel A. P. Vilela

    2015-01-01

    Full Text Available This paper provides the first reported case of acute posterior chamber hemorrhage during fluorescein angiography (FA. This is a case review with serial color photographs of the anterior segment. A 76-year-old male was referred for angiographic control of age-related macular degeneration. He was pseudophakic OU, BCVA 20/40 OU. He had mild hypertension, but not diabetes. He had had two previous angiograms without adverse effects. Difficulty was experienced in obtaining the images owing to a progressive reduction in the transparency of the media. A dense hemorrhage in the posterior chamber of the right eye was found, involving the visual axis. Thorough biomicroscopy, gonioscopy, and ultrasonic biomicroscopy showed that part of one of the haptics of the right intraocular lens (IOL was touching and tearing the posterior face of the iris, without any visible synechiae, iris, or angle neovascularization. Anterior segment FA and posterior ultrasonography were normal. No similar case has been described in the literature involving dense progressive bleeding located in the capsular bag and posterior chamber, without any detectable triggering ocular event other than mydriasis and fluorescein injection. Contact of the iris or sulcus with part of the intraocular lens, aggravated by the intense use of mydriatics during the FA procedure, probably caused bleeding to happen.

  3. Restoration of Endodontically Treated Molars Using All Ceramic Endocrowns

    Directory of Open Access Journals (Sweden)

    Roopak Bose Carlos

    2013-01-01

    Full Text Available Clinical success of endodontically treated posterior teeth is determined by the postendodontic restoration. Several options have been proposed to restore endodontically treated teeth. Endocrowns represent a conservative and esthetic restorative alternative to full coverage crowns. The preparation consists of a circular equigingival butt-joint margin and central retention cavity into the entire pulp chamber constructing both the crown and the core as a single unit. The case reports discussed here are moderately damaged endodontically treated molars restored using all ceramic endocrowns fabricated using two different systems, namely, CAD/CAM and pressed ceramic.

  4. Subcutaneous Injections

    DEFF Research Database (Denmark)

    Thomsen, Maria

    This thesis is about visualization and characterization of the tissue-device interaction during subcutaneous injection. The tissue pressure build-up during subcutaneous injections was measured in humans. The insulin pen FlexTouchr (Novo Nordisk A/S) was used for the measurements and the pressure...... build-up was evaluated indirectly from the changes in the flow rate between subcutaneous injections and air injections. This method enabled the tissue counter pressure to be evaluated without a formal clinical study approval. The measurements were coupled to a model for the pressure evolution...

  5. The ALICE time projection chamber

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    This time projection chamber is part of the ALICE detector on the new LHC accelerator at CERN. Particles produced in collisions at the core of the detector will follow paths outward through the various sub-detector layers. If these particles carry a charge, they will ionise the gas contained within this chamber producing an electric signal as the ions drift in the chamber's electric field.

  6. Ceramic Technology Project

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    The Ceramic Technology Project was developed by the USDOE Office of Transportation Systems (OTS) in Conservation and Renewable Energy. This project, part of the OTS's Materials Development Program, was developed to meet the ceramic technology requirements of the OTS's automotive technology programs. Significant accomplishments in fabricating ceramic components for the USDOE and NASA advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. These programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and data base and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. A five-year project plan was developed with extensive input from private industry. In July 1990 the original plan was updated through the estimated completion of development in 1993. The objective is to develop the industrial technology base required for reliable ceramics for application in advanced automotive heat engines. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on the structural ceramics for advanced gas turbine and diesel engines, ceramic bearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines. To facilitate the rapid transfer of this technology to US industry, the major portion of the work is being done in the ceramic industry, with technological support from government laboratories, other industrial laboratories, and universities.

  7. Injection MD

    CERN Document Server

    Bartmann, W; Bracco, C; Drosdal, L; Gianfelice, E; Goddard, B; Kain, V; Papaphilippou, Y; Vanbavinckhove, G

    2012-01-01

    This note summarizes the results obtained at injection during the 2nd MD block and the floating MD block in July. Highlights are presented for injection in the LHC with the Q20 SPS optics, influence of the supercycle and injection with 25 ns bunch spacing. Beams were successfully injected into the LHC using the Q20 optics [1, 3]. Small corrections were needed to steer the beam in the transfer lines. Dispersion measurements were conducted for both beams. The horizontal normalized dispersion in TI2 was a factor 2 smaller for Q20 with respect to Q26, for TI8 on the other hand the opposite was observed. The results for injection loss dependency on super cycle composition show only a small increase in losses for beam 2. The losses observed must therefore mainly come from other sources such as shot-by-shot stability or quality of scraping. For the injection with 25 ns bunch spacing bunches were injected for both beams. For B1 up to the maximum of 288 bunches. For B2 on the other only up to 144 bunches were injected...

  8. Industrial Ceramics: Secondary Schools.

    Science.gov (United States)

    New York City Board of Education, Brooklyn, NY. Bureau of Curriculum Development.

    The expanding use of ceramic products in today's world can be seen in the areas of communications, construction, aerospace, textiles, metallurgy, atomic energy, and electronics. The demands of science have brought ceramics from an art to an industry using mass production and automated processes which requires the services of great numbers as the…

  9. Verification of ceramic structures

    NARCIS (Netherlands)

    Behar-Lafenetre, S.; Cornillon, L.; Rancurel, M.; Graaf, D. de; Hartmann, P.; Coe, G.; Laine, B.

    2012-01-01

    In the framework of the "Mechanical Design and Verification Methodologies for Ceramic Structures" contract [1] awarded by ESA, Thales Alenia Space has investigated literature and practices in affiliated industries to propose a methodological guideline for verification of ceramic spacecraft and instr

  10. Subcutaneous Injections

    DEFF Research Database (Denmark)

    Thomsen, Maria

    This thesis is about visualization and characterization of the tissue-device interaction during subcutaneous injection. The tissue pressure build-up during subcutaneous injections was measured in humans. The insulin pen FlexTouchr (Novo Nordisk A/S) was used for the measurements and the pressure...... build-up was evaluated indirectly from the changes in the flow rate between subcutaneous injections and air injections. This method enabled the tissue counter pressure to be evaluated without a formal clinical study approval. The measurements were coupled to a model for the pressure evolution...... in subcutaneous tissue, based on mass conservation and flow in a porous medium. From the measurements the flow permeability and bulk modulus of the tissue were determined. In the adipose tissue the drug forms a bolus from where it is absorbed by the blood capillaries. The spatial distribution of the injected...

  11. The Big European Bubble Chamber

    CERN Multimedia

    1977-01-01

    The 3.70 metre Big European Bubble Chamber (BEBC), dismantled on 9 August 1984. During operation it was one of the biggest detectors in the world, producing direct visual recordings of particle tracks. 6.3 million photos of interactions were taken with the chamber in the course of its existence.

  12. Development of Fission Chamber Assembly

    Institute of Scientific and Technical Information of China (English)

    YANGJinwei; ZHANGWei; SONGXianying; LIXu

    2003-01-01

    The fission chambers which are gas counters with fissile material inside chamber,provide essential information for plasma opcharacteristics. In conjunction with the neutron flux monitor system these provide time-resolved measurements of the global neutron source strength and fusion power from thermal nuclear fusion reactor as ITER for all plasma conditions for which neutrons are produced.

  13. National Ignition Facility Target Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Wavrik, R W; Cox, J R; Fleming, P J

    2000-10-05

    On June 11, 1999 the Department of Energy dedicated the single largest piece of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in Livermore, California. The ten (10) meter diameter aluminum target high vacuum chamber will serve as the working end of the largest laser in the world. The output of 192 laser beams will converge at the precise center of the chamber. The laser beams will enter the chamber in two by two arrays to illuminate 10 millimeter long gold cylinders called hohlraums enclosing 2 millimeter capsule containing deuterium, tritium and isotopes of hydrogen. The two isotopes will fuse, thereby creating temperatures and pressures resembling those found only inside stars and in detonated nuclear weapons, but on a minute scale. The NIF Project will serve as an essential facility to insure safety and reliability of our nation's nuclear arsenal as well as demonstrating inertial fusion's contribution to creating electrical power. The paper will discuss the requirements that had to be addressed during the design, fabrication and testing of the target chamber. A team from Sandia National Laboratories (SNL) and LLNL with input from industry performed the configuration and basic design of the target chamber. The method of fabrication and construction of the aluminum target chamber was devised by Pitt-Des Moines, Inc. (PDM). PDM also participated in the design of the chamber in areas such as the Target Chamber Realignment and Adjustment System, which would allow realignment of the sphere laser beams in the event of earth settlement or movement from a seismic event. During the fabrication of the target chamber the sphericity tolerances had to be addressed for the individual plates. Procedures were developed for forming, edge preparation and welding of individual plates. Construction plans were developed to allow the field construction of the target chamber to occur parallel to other NIF construction activities. This

  14. Ceramics As Materials Of Construction

    OpenAIRE

    Zaki, A.; Eteiba, M. B.; Abdelmonem, N.M.

    1988-01-01

    This paper attempts to review the limitations for using the important ceramics in contact with corrosive media. Different types of ceramics are included. Corrosion properties of ceramics and their electrical properties are mentioned. Recommendations are suggested for using ceramics in different media.

  15. The CLEO III drift chamber

    CERN Document Server

    Peterson, D; Briere, R A; Chen, G; Cronin-Hennessy, D; Csorna, S; Dickson, M; Dombrowski, S V; Ecklund, K M; Lyon, A; Marka, S; Meyer, T O; Patterson, J R; Sadoff, A; Thies, P; Thorndike, E H; Urner, D

    2002-01-01

    The CLEO group at the Cornell Electron Storage Ring has constructed and commissioned a new central drift chamber. With 9796 cells arranged in 47 layers ranging in radius from 13.2 to 79 cm, the new drift chamber has a smaller outer radius and fewer wires than the drift chamber it replaces, but allows the CLEO tracking system to have improved momentum resolution. Reduced scattering material in the chamber gas and in the inner skin separating the drift chamber from the silicon vertex detector provides a reduction of the multiple scattering component of the momentum resolution and an extension of the usable measurement length into the silicon. Momentum resolution is further improved through quality control in wire positioning and symmetry of the electric fields in the drift cells which have provided a reduction in the spatial resolution to 88 mu m (averaged over the full drift range).

  16. Ion chamber based neutron detectors

    Science.gov (United States)

    Derzon, Mark S; Galambos, Paul C; Renzi, Ronald F

    2014-12-16

    A neutron detector with monolithically integrated readout circuitry, including: a bonded semiconductor die; an ion chamber formed in the bonded semiconductor die; a first electrode and a second electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; and the readout circuitry which is electrically coupled to the first and second electrodes. The bonded semiconductor die includes an etched semiconductor substrate bonded to an active semiconductor substrate. The readout circuitry is formed in a portion of the active semiconductor substrate. The ion chamber has a substantially planar first surface on which the first electrode is formed and a substantially planar second surface, parallel to the first surface, on which the second electrode is formed. The distance between the first electrode and the second electrode may be equal to or less than the 50% attenuation length for neutrons in the neutron absorbing material filling the ion chamber.

  17. Why do we develope a ceramics heat insulated engine. Ceramic engine wo ikani kaihatsu suruka

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, H. (Isuzu Motors 1td., Tokyo (Japan))

    1990-10-20

    This paper introduces the development of ceramics engines. If pistons and cylinder liners, etc. are constructed by the use of silicon nitrides which are expected as structure-use ceramics and combined with the insulated structure of the outer circumference of the engine, the cooling system of the engine can be removed and the engine becomes extremely light and compact one without a radiator, a fun and a cooling jacket. The thermal insulated turbo compound engine now under development is the system in which the combustion chamber is constructed by the use of ceramics. The heat energy which used to be diffused into the cooling system is displaced to the exhaust gas side and the high temperature exhaust gas drives turbines to generate power. In order to make use of not only the above-mentioned thermal insulation and heat resistance but light weight, wear resistance and low friction, ceramics parts more than 15 kinds are used for the engine. Improvement over 30% in heat efficiency is aimed at for this engine. 5 refs., 4 figs.

  18. Mepolizumab Injection

    Science.gov (United States)

    ... or do not go away: pain, redness, swelling, warmth, burning, or itching in the place mepolizumab was injected headache dry and itchy skin with or without red, scaly rashes back pain muscle spasms Some side ...

  19. Metoclopramide Injection

    Science.gov (United States)

    ... and feeling of fullness that lasts long after meals. Metoclopramide injection is also used to prevent nausea ... tranylcypromine (Parnate); narcotic medications for pain; sedatives; sleeping pills; tetracycline (Bristacycline, Sumycin); tranquilizers. Your doctor may need ...

  20. Ramucirumab Injection

    Science.gov (United States)

    ... dose of ramucirumab injection. Tell your doctor or nurse if you experience any of the following while you receive ramucirumab: uncontrollable shaking of a part of the body; back pain or spasms; chest pain and tightness; chills; flushing; ...

  1. Alemtuzumab Injection

    Science.gov (United States)

    Alemtuzumab injection is used to treat B-cell chronic lymphocytic leukemia (a slowly developing cancer in which ... of white blood cell accumulate in the body). Alemtuzumab is in a class of medications called monoclonal ...

  2. Ferumoxytol Injection

    Science.gov (United States)

    Ferumoxytol injection is used to treat iron-deficiency anemia (a lower than normal number of red blood ... pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or ...

  3. Fludarabine Injection

    Science.gov (United States)

    Fludarabine injection is used to treat chronic lymphocytic leukemia (CLL; a type of cancer of the white ... a reliable method of birth control to prevent pregnancy during this time. Talk to your doctor for ...

  4. Insulin Injection

    Science.gov (United States)

    ... or buttocks. Do not inject insulin into muscles, scars, or moles. Use a different site for each ... you are using insulin.Alcohol may cause a decrease in blood sugar. Ask your doctor about the ...

  5. Tigecycline Injection

    Science.gov (United States)

    ... in a person who was not in the hospital), skin infections, and infections of the abdomen (area between the ... that developed in people who were in a hospital or foot infections in people who have diabetes. Tigecycline injection is ...

  6. Golimumab Injection

    Science.gov (United States)

    Golimumab injection is used alone or with other medications to relieve the symptoms of certain autoimmune disorders ( ... did not help or could not be tolerated. Golimumab is in a class of medications called tumor ...

  7. Albiglutide Injection

    Science.gov (United States)

    ... will develop tumors of the thyroid gland, including medullary thyroid carcinoma (MTC; a type of thyroid cancer). ... symptoms or those listed in the IMPORTANT WARNING section, stop using albiglutide injection and call your doctor ...

  8. Dexamethasone Injection

    Science.gov (United States)

    ... body tissues,) gastrointestinal disease, and certain types of arthritis. Dexamethasone injection is also used for diagnostic testing. ... effects.tell your doctor if you have a fungal infection (other than on your skin or nails). ...

  9. Hydrocortisone Injection

    Science.gov (United States)

    ... own organs), gastrointestinal disease, and certain types of arthritis. Hydrocortisone injection is also used to treat certain ... effects.tell your doctor if you have a fungal infection (other than on your skin or nails). ...

  10. Methylprednisolone Injection

    Science.gov (United States)

    ... own organs), gastrointestinal disease, and certain types of arthritis. Methylprednisolone injection is also used to treat certain ... effects.tell your doctor if you have a fungal infection (other than on your skin or nails). ...

  11. Glatiramer Injection

    Science.gov (United States)

    ... To inject glatiramer, follow these steps: Remove one blister pack from the carton of glatiramer syringes and place ... paper label and remove the syringe from the blister pack. Check your prefilled syringe to be sure it ...

  12. Dexrazoxane Injection

    Science.gov (United States)

    ... that are used to treat or prevent certain side effects that may be caused by chemotherapy medications. Dexrazoxane injection (Zinecard) is used to prevent or decrease heart damage caused by doxorubicin in women who are ...

  13. Evolocumab Injection

    Science.gov (United States)

    ... autoinjector in hot water, microwave, or place in sunlight.Before you use evolocumab injection, look at the ... chills pain or burning during urination muscle or back pain dizziness stomach pain Some side effects can be ...

  14. Cidofovir Injection

    Science.gov (United States)

    Cidofovir injection is used along with another medication (probenecid) to treat cytomegaloviral retinitis (CMV retinitis) in people with acquired immunodeficiency syndrome (AIDS). Cidofovir is in a class of medications called antivirals. ...

  15. Brivaracetam Injection

    Science.gov (United States)

    ... older. Brivaracetam in a class of medications called anticonvulsants. It works by decreasing abnormal electrical activity in ... older (about 1 in 500 people) who took anticonvulsants like brivaracetam injection to treat various conditions during ...

  16. Diphenhydramine Injection

    Science.gov (United States)

    ... not to use diphenhydramine injection if you are breastfeeding because of the risk of harm to infants.tell your doctor if you have or have ever had asthma or other types of lung disease; glaucoma (a ...

  17. Cefazolin Injection

    Science.gov (United States)

    ... valve, respiratory tract (including pneumonia), biliary tract, and urinary tract infections. Cefazolin injection also may be used before, during, ... to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( ...

  18. Ceftazidime Injection

    Science.gov (United States)

    ... skin, blood, bone, joint, female genital tract, and urinary tract infections. Ceftazidime injection is in a class of medications ... to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( ...

  19. Fluconazole Injection

    Science.gov (United States)

    ... and fungal infections of the eye, prostate (a male reproductive organ), skin and nails. Fluconazole injection is ... Motrin, others) and naproxen (Aleve, Anaprox, Naprelan); oral contraceptives (birth control pills); oral medication for diabetes such ...

  20. Moxifloxacin Injection

    Science.gov (United States)

    ... available.Moxifloxacin injection is in a class of antibiotics called fluoroquinolones. It works by killing the bacteria that cause ... you are allergic to moxifloxacin, other quinolone or fluoroquinolone antibiotics such as ciprofloxacin (Cipro), gatifloxacin (Tequin) (not available ...

  1. Levofloxacin Injection

    Science.gov (United States)

    ... available. Levofloxacin injection is in a class of antibiotics called fluoroquinolones. It works by killing bacteria that cause infections. ... severe reaction to levofloxacin; any other quinolone or fluoroquinolone antibiotic such as ciprofloxacin (Cipro), gatifloxacin (Tequin) (not available ...

  2. Ciprofloxacin Injection

    Science.gov (United States)

    ... available. Ciprofloxacin injection is in a class of antibiotics called fluoroquinolones. It works by killing bacteria that cause infections. ... reaction to ciprofloxacin or any other quinolone or fluoroquinolone antibiotic such as gatifloxacin (Tequin) (not available in the ...

  3. Alirocumab Injection

    Science.gov (United States)

    ... further decrease the amount of low-density lipoprotein (LDL) cholesterol ('bad cholesterol') in the blood. Alirocumab injection is ... antibodies. It works by blocking the production of LDL cholesterol in the body to decrease the amount of ...

  4. Chloramphenicol Injection

    Science.gov (United States)

    ... an arm or leg sudden changes in vision pain with eye movement Chloramphenicol injection may cause a condition called gray syndrome in premature and newborn infants. There have also been reports of gray ...

  5. Technology developments for thrust chambers of future launch vehicle liquid rocket engines

    Energy Technology Data Exchange (ETDEWEB)

    Immich, H.; Alting, J.; Kretschmer, J.; Preclik, D. [Astrium GmbH, Space Infrastructure Div. Advanced Programs and System Engineering, Munich (Germany)

    2003-11-01

    In this paper an overview of recent technology developments for thrust chambers of future launch vehicle liquid rocket engines at Astrium, Space Infrastructure Division (SI), is shown. The main technology developments shown in this paper are: Technologies for enhanced heat transfer to the coolant for expander cycle engines. Advanced injector head technologies. Advanced combustion chamber manufacturing technologies. The main technologies for enhanced heat transfer investigated by subscale chamber hot-firing tests are: Increase of chamber length. Hot gas side ribs in the chamber. Artificially increased surface roughness. The developments for advanced injector head technologies were focused on the design of a new modular subscale chamber injector head. This injector head allows for an easy exchange of different injection elements: By this, cost effective hot-fire tests with different injection element concepts can be performed. The developments for advanced combustion chamber manufacturing technologies are based on subscale chamber tests with a new design of the Astrium subscale chamber. The subscale chamber has been modified by introduction of a segmented cooled cylindrical section which gives the possibility to test different manufacturing concepts for cooled chamber technologies by exchanging the individual segments. The main technology efforts versus advanced manufacturing technologies shown in this paper are: Soldering techniques. Thermal barrier coatings for increased chamber life. A new technology effort is dedicated especially to LOX/Hydrocarbon propellant combinations. Recent hot fire tests on the sub scale chamber with Kerosene and Methane as fuel have already been performed. A comprehensive engine system trade-off between the both propellant combinations (Kerosene vs. Methane) is presently under preparation. (Author)

  6. Technology developments for thrust chambers of future launch vehicle liquid rocket engines

    Science.gov (United States)

    Immich, H.; Alting, J.; Kretschmer, J.; Preclik, D.

    2003-08-01

    In this paper an overview of recent technology developments for thrust chambers of future launch vehicle liquid rocket engines at Astrium, Space Infrastructure Division (SI), is shown. The main technology. developments shown in this paper are: Technologies Technologies for enhanced heat transfer to the coolant for expander cycle engines Advanced injector head technologies Advanced combustion chamber manufacturing technologies. The main technologies for enhanced heat transfer investigated by subscale chamber hot-firing tests are: Increase of chamber length Hot gas side ribs in the chamber Artificially increased surface roughness. The developments for advanced injector head technologies were focused on the design of a new modular subscale chamber injector head. This injector head allows for an easy exchange of different injection elements: By this, cost effective hot-fire tests with different injection element concepts can be performed. The developments for advanced combustion chamber manufacturing technologies are based on subscale chamber tests with a new design of the Astrium subscale chamber. The subscale chamber has been modified by introduction of a segmented cooled cylindrical section which gives the possibility to test different manufacturing concepts for cooled chamber technologies by exchanging the individual segments. The main technology efforts versus advanced manufacturing technologies shown in this paper are: Soldering techniques Thermal barrier coatings for increased chamber life. A new technology effort is dedicated especially to LOX/Hydrocarbon propellant combinations. Recent hot fire tests on the subscale chamber with Kerosene and Methane as fuel have already been performed. A comprehensive engine system trade-off between the both propellant combinations (Kerosene vs. Methane) is presently under preparation.

  7. High pressure ceramic joint

    Science.gov (United States)

    Ward, Michael E.; Harkins, Bruce D.

    1993-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  8. Emissivities of ceramic fibre linings for high-temperature furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, J.D.; Williams, A.

    1984-09-01

    Measurements have been made of the emissivities of ceramic fibre linings of the type used for low thermal mass high-temperature furnaces. The apparatus used consisted of a circular ceramic fibre lined combustion chamber heated by a natural gas burner. The surface temperature of the rear wall was monitored by a number of thermocouples mounted near the surface. The radiant flux from this wall was measured over the temperature range of 700-1400 K and by comparison with emission from a black body, the emissivities of the surface were determined. It was found that the emissivity varied with the type of surface and with temperature. The stack-bonded Kaowool ceramic fibres had a higher emissivity than parallel-bonded fibres, the values at 1400 K being 0.66 and 0.5 respectively; 'damaged' stack-bonded fibres had an intermediate value.

  9. Effects of oxygen and nitrogen on the character of T. pallidum is subcutaneous chambers in mice.

    Science.gov (United States)

    Horvath, I; Arko, R J; Bullard, J C

    1975-01-01

    Nitrogen and oxygen gases were injected into mouse subcutaneous chambers which contained virulent Treponema pallidum. The effect of each gas on the viability and survival of T. pallidum in an in vivo system was determined. In comparison with the effects in nontreated control mice, injection of nitrogen enhanced both motility and survival time, but oxygen exerted a deleterious effect. Images PMID:1104074

  10. Alkaline resistant ceramics; Alkalimotstaandskraftiga keramer

    Energy Technology Data Exchange (ETDEWEB)

    Westberg, Stig-Bjoern [Vattenfall Utveckling AB, Aelvkarleby (Sweden)

    2001-02-01

    Despite durability in several environments, ceramics and refractories can not endure alkaline environments at high temperature. An example of such an environment is when burning biofuel in modern heat and power plants in which the demand for increasing efficiency results in higher combustion temperatures and content of alkaline substances in the flue gas. Some experiences of these environments has been gained from such vastly different equipment as regenerator chambers in the glass industry and MHD-generators. The grains of a ceramic material are usually bonded together by a glassy phase which despite it frequently being a minor constituent render the materials properties and limits its use at elevated temperature. The damage is usually caused by alkaline containing low-melting phases and the decrease of the viscosity of the bonding glass phase which is caused by the alkaline. The surfaces which are exposed to the flue gas in a modern power plant are not only exposed to the high temperature but also a corroding and eroding, particle containing, gas flow of high velocity. The use of conventional refractory products is limited to 1300-1350 deg C. Higher strength and fracture toughness as well as durability against gases, slag and melts at temperatures exceeding 1700 deg C are expected of the materials of the future. Continuous transport of corrosive compounds to the surface and corrosion products from the surface as well as a suitable environment for the corrosion to occur in are prerequisites for extensive corrosion to come about. The highest corrosion rate is therefore found in a temperature interval between the dew point and the melting point of the alkaline-constituent containing compound. It is therefore important that the corrosion resistance is sufficient in the environment in which alkaline containing melts or slag may appear. In environments such as these, even under normal circumstances durable ceramics, such as alumina and silicon carbide, are attacked

  11. Promoted-Combustion Chamber with Induction Heating Coil

    Science.gov (United States)

    Richardson, Erin; Hagood, Richard; Lowery, Freida; Herald, Stephen

    2006-01-01

    An improved promoted-combustion system has been developed for studying the effects of elevated temperatures on the flammability of metals in pure oxygen. In prior promoted-combustion chambers, initial temperatures of metal specimens in experiments have been limited to the temperatures of gas supplies, usually near room temperature. Although limited elevated temperature promoted-combustion chambers have been developed using water-cooled induction coils for preheating specimens, these designs have been limited to low-pressure operation due to the hollow induction coil. In contrast, the improved promoted-combustion chamber can sustain a pressure up to 10 kpsi (69 MPa) and, through utilization of a solid induction coil, is capable of preheating a metal specimen up to its melting point [potentially in excess of 2,000 F (approximately equal to 1,100 C)]. Hence, the improved promoted combustion chamber makes a greater range of physical conditions and material properties accessible for experimentation. The chamber consists of a vertical cylindrical housing with an inner diameter of 8 in. (20.32 cm) and an inner height of 20.4 in. (51.81 cm). A threaded, sealing cover at one end of the housing can be unscrewed to gain access for installing a specimen. Inlet and outlet ports for gases are provided. Six openings arranged in a helical pattern in the chamber wall contain sealed sapphire windows for viewing an experiment in progress. The base of the chamber contains pressure-sealed electrical connectors for supplying power to the induction coil. The connectors feature a unique design that prevents induction heating of the housing and the pressure sealing surfaces; this is important because if such spurious induction heating were allowed to occur, chamber pressure could be lost. The induction coil is 10 in. (25.4 cm) long and is fitted with a specimen holder at its upper end. At its lower end, the induction coil is mounted on a ceramic base, which affords thermal insulation to

  12. Robocasting of Ceramics and Composites Using Fine Particle Suspensions

    Energy Technology Data Exchange (ETDEWEB)

    CESARANO III,JOSEPH

    1999-10-28

    Solid freeform fabrication is the near-net-shape manufacturing of components by sequentially stacking thin layers of material until complicated three dimensional shapes are produced. The operation is computer controlled and requires no molds. This exciting new field of technology provides engineers with the ability to rapidly produce prototype parts directly from CAD drawings and oftentimes little or no machining is necessary after fabrication. Techniques for freeform fabrication with several types of plastics and metals are already quite advanced and maybe reviewed in references 1 and 2. Very complicated plastic models can be fabricated by stereolithography, selective laser sintering, fused deposition modeling, or three-dimensional ink jet printing. Metals may be freeformed by the LENS{trademark} technique and porous ceramic bodies by three dimensional printing into a porous powder bed. However, methods for freeform fabrication that utilize particulate slurries to build dense ceramics and composites are not as well developed. The techniques that are being developed for the freeform fabrication of dense structural ceramics primarily revolve around the sequential layering of ceramic loaded polymers or waxes. Laminated Object Manufacturing and CAM-LEM processing use controlled stacking and laser cutting of ceramic tapes [2,3]. Similar to fused deposition modeling, ceramic loaded polymer/wax filaments are being used for the fused deposition of ceramics [2,4]. Extrusion freeform fabrication uses high pressure extrusion to deposit layers of ceramic loaded polymer/wax systems[1]. Modified stereolithographic techniques are also being developed using ceramic loaded ultraviolet curable resins [2]. Pre-sintered parts made with any of these techniques typically have 40-55 vol.% polymeric binder. In this regard, these techniques are analogous to powder injection molding of ceramics. Very long and complicated burnout heat treatments are necessary to produce a dense ceramic

  13. Noninvasive optical interrogation of the ocular anterior chamber

    Science.gov (United States)

    Blue, Robert; Uttamchandani, Deepak G.; Wilson, Clive G.

    1998-06-01

    Ophthalmic drug research and ocular diagnostics is hampered by an inability to perform continuous sampling of the aqueous humor contained within the anterior chamber by paracentesis is technically problematic and is associated with the use of local or general anesthesia. Moreover, sampling by direct injection exposes the eye to the risk of infection. We report results obtained from an optical instrumentation technique which is concerned with the direct and non-invasive measurements of optical scattering, absorbance and fluorescence produced in the aqueous humor by various compounds, thus avoiding the need for direct sampling. Light scatter in the anterior chamber arises from particulate matter, such as cell debris and chemical precipitates following eye surgery. Absorbance is caused by the presence of materials such as haemoglobin, or results from the penetration of drugs such as hydroxyquinolines applied to the cornea. Fluorescence can be used to provide a sensitive measurements of fluoroquinolines in the anterior chamber.

  14. Advanced Ceramics Property Measurements

    Science.gov (United States)

    Salem, Jonathan; Helfinstine, John; Quinn, George; Gonczy, Stephen

    2013-01-01

    Mechanical and physical properties of ceramic bodies can be difficult to measure correctly unless the proper techniques are used. The Advanced Ceramics Committee of ASTM, C-28, has developed dozens of consensus test standards and practices to measure various properties of a ceramic monolith, composite, or coating. The standards give the "what, how, how not, and why" for measurement of many mechanical, physical, thermal, and performance properties. Using these standards will provide accurate, reliable, and complete data for rigorous comparisons with other test results from your test lab, or another. The C-28 Committee has involved academics, producers, and users of ceramics to write and continually update more than 45 standards since the committee's inception in 1986. Included in this poster is a pictogram of the C-28 standards and information on how to obtain individual copies with full details or the complete collection of standards in one volume.

  15. Ceramic fiber filter technology

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, B.L.; Janney, M.A.

    1996-06-01

    Fibrous filters have been used for centuries to protect individuals from dust, disease, smoke, and other gases or particulates. In the 1970s and 1980s ceramic filters were developed for filtration of hot exhaust gases from diesel engines. Tubular, or candle, filters have been made to remove particles from gases in pressurized fluidized-bed combustion and gasification-combined-cycle power plants. Very efficient filtration is necessary in power plants to protect the turbine blades. The limited lifespan of ceramic candle filters has been a major obstacle in their development. The present work is focused on forming fibrous ceramic filters using a papermaking technique. These filters are highly porous and therefore very lightweight. The papermaking process consists of filtering a slurry of ceramic fibers through a steel screen to form paper. Papermaking and the selection of materials will be discussed, as well as preliminary results describing the geometry of papers and relative strengths.

  16. Making Ceramic Cameras

    Science.gov (United States)

    Squibb, Matt

    2009-01-01

    This article describes how to make a clay camera. This idea of creating functional cameras from clay allows students to experience ceramics, photography, and painting all in one unit. (Contains 1 resource and 3 online resources.)

  17. Making Ceramic Cameras

    Science.gov (United States)

    Squibb, Matt

    2009-01-01

    This article describes how to make a clay camera. This idea of creating functional cameras from clay allows students to experience ceramics, photography, and painting all in one unit. (Contains 1 resource and 3 online resources.)

  18. Chamber and target technology development for inertial fusion energy

    Energy Technology Data Exchange (ETDEWEB)

    Abdou, M; Besenbruch, G; Duke, J; Forman, L; Goodin, D; Gulec, K; Hoffer, J; Khater, H; Kulcinsky, G; Latkowski, J F; Logan, B G; Margevicious, B; Meier, W R; Moir, R W; Morley, N; Nobile, A; Payne, S; Peterson, P F; Peterson, R; Petzoldt, R; Schultz, K; Steckle, W; Sviatoslavsky, L; Tillack, M; Ying, A

    1999-04-07

    Fusion chambers and high pulse-rate target systems for inertial fusion energy (IFE) must: regenerate chamber conditions suitable for target injection, laser propagation, and ignition at rates of 5 to 10 Hz; extract fusion energy at temperatures high enough for efficient conversion to electricity; breed tritium and fuel targets with minimum tritium inventory; manufacture targets at low cost; inject those targets with sufficient accuracy for high energy gain; assure adequate lifetime of the chamber and beam interface (final optics); minimize radioactive waste levels and annual volumes; and minimize radiation releases under normal operating and accident conditions. The primary goal of the US IFE program over the next four years (Phase I) is to develop the basis for a Proof-of-Performance-level driver and target chamber called the Integrated Research Experiment (IRE). The IRE will explore beam transport and focusing through prototypical chamber environment and will intercept surrogate targets at high pulse rep-rate. The IRE will not have enough driver energy to ignite targets, and it will be a non-nuclear facility. IRE options are being developed for both heavy ion and laser driven IFE. Fig. 1 shows that Phase I is prerequisite to an IRE, and the IRE plus NIF (Phase II) is prerequisite to a high-pulse rate. Engineering Test Facility and DEMO for IFE, leading to an attractive fusion power plant. This report deals with the Phase-I R&D needs for the chamber, driver/chamber interface (i.e., magnets for accelerators and optics for lasers), target fabrication, and target injection; it is meant to be part of a more comprehensive IFE development plan which will include driver technology and target design R&D. Because of limited R&D funds, especially in Phase I, it is not possible to address the critical issues for all possible chamber and target technology options for heavy ion or laser fusion. On the other hand, there is risk in addressing only one approach to each technology

  19. The multigap resistive plate chamber

    Energy Technology Data Exchange (ETDEWEB)

    Zeballos, E. Cerron [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Crotty, I. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Hatzifotiadou, D. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Valverde, J. Lamas [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Univ. Louis Pasteur, Strasbourg (France); Neupane, S. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Williams, M. C. S. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Zichichi, A. [Univ. of Bologna, Bologna (Italy)

    2015-02-03

    The paper describes the multigap resistive plate chamber (RPC). This is a variant of the wide gap RPC. However it has much improved time resolution, while keeping all the other advantages of the wide gap RPC design.

  20. Cyclically controlled welding purge chamber

    Science.gov (United States)

    Gallagher, Robert L. (Inventor)

    1996-01-01

    An arrangement for butt-welding cylindrical sections of large, thin-wall tanks includes a rotatable mandrel with side-by-side sets of radial position adjusters. Each set of adjusters bears on one of the tank sections adjacent the seam, to prevent the sections from sagging out-of-round. The mandrel rotates relative to the welder, so that a continuous seam is formed. A purge chamber is fixed in position behind the seam at the weld head, and is flushed with inert gas. The purge chamber includes a two-sided structure which is contiguous with the cylindrical sections and a circumferential vane to form an open-ended tube-like structure, through which the radial position adjusters pass as the mandrel and cylindrical workpiece sections rotate. The tube-like structure is formed into a chamber by a plurality of movable gates which are controlled to maintain a seal while allowing adjusters to progress through the purge chamber.

  1. The PHENIX Time Expansion Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Rosati, M.; Barish, K.; Botelho, S.; Chang, W.C.; Gogoi, A.L. de; Dietzsch, O.; Ferdousi, T.; Franz, A.; Fung, S.Y.; Gannon, J.; Harder, J.; Kandasamy, A.; Khomutnikov, A.; Kotchekov, D.; Lebedev, A.; Li, X.H.; Mahon, J.; Munirassimann, M.; Negrin, J.; O' Brien, E.; O' Connor, P.; Pisani, R.; Rankowitz, S.; Seto, R.; Takagui, E.M.; Wang, H.Q

    1999-12-27

    The TEC/TRD subsystem will track all charged particles and contribute to the particle identification by the measurement of energy loss. The design, construction and testing of the TEC chambers are described.

  2. The PHENIX Time Expansion Chamber

    CERN Document Server

    Rosati, M; Botelho, S; Chang, W C; Gogoi, A L D; Dietzsch, O; Ferdousi, T; Franz, A; Fung, S Y; Gannon, J; Harder, J; Kandasamy, A; Khomutnikov, A; Kotchekov, D; Lebedev, A; Li, X H; Mahon, J; Munirassimann, M; Negrin, J; O'Brien, E; O'Connor, P; Pisani, R; Rankowitz, S; Seto, R; Takagui, E M; Wang, H Q

    1999-01-01

    The TEC/TRD subsystem will track all charged particles and contribute to the particle identification by the measurement of energy loss. The design, construction and testing of the TEC chambers are described.

  3. Vacuum chambers for LHC LSS

    CERN Document Server

    Costa-Pinto, P

    2004-01-01

    The approximately 6 km total length of the Large Hadron Collider (LHC) warm sections consist of about 1000 chambers. Most of these chambers, of various length and cross sections, are made of copper, but different lengths in stainless steel, mumetal, aluminium and beryllium will also be used. All the chambers will be internally coated with a thin film of TiZrV, to reduce both the secondary electron yield and the photon and electron stimulated desorption, with the further advantage of providing a huge additional pumping speed. In order to cope with the tight production schedule, a new dedicated coating facility was created, which allows four chambers to be coated per working day. This coating facility and its operating mode are described, together with the TiZrV film characteristics (structure, morphology) and performance (pumping speed, ultimate pressure, discharge gas outgassing).

  4. Vaporization chambers and associated methods

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Terry D.; Wilding, Bruce M.; McKellar, Michael G.; Shunn, Lee P.

    2017-02-21

    A vaporization chamber may include at least one conduit and a shell. The at least one conduit may have an inlet at a first end, an outlet at a second end and a flow path therebetween. The shell may surround a portion of each conduit and define a chamber surrounding the portion of each conduit. Additionally, a plurality of discrete apertures may be positioned at longitudinal intervals in a wall of each conduit, each discrete aperture of the plurality of discrete apertures sized and configured to direct a jet of fluid into each conduit from the chamber. A liquid may be vaporized by directing a first fluid comprising a liquid into the inlet at the first end of each conduit, directing jets of a second fluid into each conduit from the chamber through discrete apertures in a wall of each conduit and transferring heat from the second fluid to the first fluid.

  5. OXYGEN TRANSPORT CERAMIC MEMBRANES

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2000-07-01

    This is the fourth quarterly report on a new study to develop a ceramic membrane/metal joint. The first experiments using the La-Sr-Fe-O ceramic are reported. Some of the analysis performed on the samples obtained are commented upon. A set of experiments to characterize the mechanical strength and thermal fatigue properties of the joints has been designed and begun. Finite element models of joints used to model residual stresses are described.

  6. BEBC Big European Bubble Chamber

    CERN Multimedia

    CERN PhotoLab

    1974-01-01

    A view of the dismantling of the magnet of BEBC, the 3.7 m European Bubble Chamber : iron magnetic shielding ; lower and upper parts of the vacuum enclosure of the magnet; turbo-molecular vacuum pumps for the "fish-eye" windows; the two superconducting coils; a handling platform; the two cryostats suspended from the bar of the travelling crane which has a 170 ton carrying capacity. The chamber proper, not dismantled, is inside the shielding.

  7. Isotopic evidence for multiple contributions to felsic magma chambers

    DEFF Research Database (Denmark)

    Waight, Tod Earle; Wiebe, R.A.; Krogstad, E.J.

    2007-01-01

    by contemporaneous mafic magmas; the transition between the two now preserved as a zone of chilled mafic sheets and pillows in granite. Mafic components have highly variably isotopic compositions as a result of contamination either at depth or following injection into the magma chamber. Intermediate dikes...... with identical isotopic compositions to more mafic dikes suggest that closed system fractionation may be occurring in deeper level chambers prior to injection to shallower levels. The granitic portion of the pluton has the highest Nd isotopic composition (eNd=+3.0) of plutons in the region whereas the mafic...... lithologies have Nd isotopic compositions (eNd=+3.5) that are the lowest in the region and similar to the granite and suggestive of prolonged interactions and homogenization of the two components. Sr and Nd isotopic data for felsic enclaves are inconsistent with previously suggested models of diffusional...

  8. Degradability of dental ceramics.

    Science.gov (United States)

    Anusavice, K J

    1992-09-01

    The degradation of dental ceramics generally occurs because of mechanical forces or chemical attack. The possible physiological side-effects of ceramics are their tendency to abrade opposing dental structures, the emission of radiation from radioactive components, the roughening of their surfaces by chemical attack with a corresponding increase in plaque retention, and the release of potentially unsafe concentrations of elements as a result of abrasion and dissolution. The chemical durability of dental ceramics is excellent. With the exception of the excessive exposure to acidulated fluoride, ammonium bifluoride, or hydrofluoric acid, there is little risk of surface degradation of virtually all current dental ceramics. Extensive exposure to acidulated fluoride is a possible problem for individuals with head and/or neck cancer who have received large doses of radiation. Such fluoride treatment is necessary to minimize tooth demineralization when saliva flow rates have been reduced because of radiation exposure to salivary glands. Porcelain surface stains are also lost occasionally when abraded by prophylaxis pastes and/or acidulated fluoride. In each case, the solutes are usually not ingested. Further research that uses standardized testing procedures is needed on the chemical durability of dental ceramics. Accelerated durability tests are desirable to minimize the time required for such measurements. The influence of chemical durability on surface roughness and the subsequent effect of roughness on wear of the ceramic restorations as well as of opposing structures should also be explored on a standardized basis.

  9. Anterior chamber depth during hemodialysis

    Directory of Open Access Journals (Sweden)

    Gracitelli CPB

    2013-08-01

    Full Text Available Carolina Pelegrini Barbosa Gracitelli,1 Francisco Rosa Stefanini,1 Fernando Penha,1 Miguel Ângelo Góes,2 Sérgio Antonio Draibe,2 Maria Eugênia Canziani,2 Augusto Paranhos Junior1 1Ophthalmology Department, 2Division of Nephrology, Federal University of São Paulo – UNIFESP, São Paulo, Brazil Background: Exacerbation of chronic glaucoma or acute glaucoma is occasionally observed in patients undergoing hemodialysis (HD because of anterior chamber depth changes during this therapy. Purpose: To evaluate anterior chamber depth and axial length in patients during HD sessions. Methods: A total of 67 eyes of 35 patients were prospectively enrolled. Axial length and anterior chamber depth were measured using ultrasonic biometry, and these measures were evaluated at three different times during HD sessions. Body weight and blood pressure pre- and post-HD were also measured. Results: There was no difference in the axial length between the three measurements (P = 0.241. We observed a significantly decreased anterior chamber depth (P = 0.002 during HD sessions. Conclusion: Our results support the idea that there is a change in anterior chamber depth in HD sessions. Keywords: anterior chamber, hemodialysis, axial length, acute angle-closure glaucoma

  10. Clinical application of bio ceramics

    Science.gov (United States)

    Anu, Sharma; Gayatri, Sharma

    2016-05-01

    Ceramics are the inorganic crystalline material. These are used in various field such as biomedical, electrical, electronics, aerospace, automotive and optical etc. Bio ceramics are the one of the most active areas of research. Bio ceramics are the ceramics which are biocompatible. The unique properties of bio ceramics make them an attractive option for medical applications and offer some potential advantages over other materials. During the past three decades, a number of major advances have been made in the field of bio ceramics. This review focuses on the use of these materials in variety of clinical scenarios.

  11. Hydrogen silsesquioxane mold coatings for improved replication of nanopatterns by injection molding

    DEFF Research Database (Denmark)

    Hobæk, Thor Christian; Matschuk, Maria; Kafka, Jan;

    2015-01-01

    We demonstrate the replication of nanosized pillars in polymer (cyclic olefin copolymer) by injection molding using nanostructured thermally cured hydrogen silsesquioxane (HSQ) ceramic coatings on stainless steel mold inserts with mold nanostructures produced by a simple embossing process...

  12. Sensor for Injection Rate Measurements

    Directory of Open Access Journals (Sweden)

    Milan Marcic

    2006-10-01

    Full Text Available A vast majority of the medium and high speed Diesel engines are equipped withmulti-hole injection nozzles nowadays. Inaccuracies in workmanship and changinghydraulic conditions in the nozzles result in differences in injection rates between individualinjection nozzle holes. The new deformational measuring method described in the paperallows injection rate measurement in each injection nozzle hole. The differences in injectionrates lead to uneven thermal loads of Diesel engine combustion chambers. All today knownmeasuring method, such as Bosch and Zeuch give accurate results of the injection rate indiesel single-hole nozzles. With multihole nozzles they tell us nothing about possibledifferences in injection rates between individual holes of the nozzle. At deformationalmeasuring method, the criterion of the injected fuel is expressed by the deformation ofmembrane occurring due to the collision of the pressure wave against the membrane. Thepressure wave is generated by the injection of the fuel into the measuring space. For eachhole of the nozzle the measuring device must have a measuring space of its own into whichfuel is injected as well as its measuring membrane and its own fuel outlet. Duringmeasurements procedure the measuring space must be filled with fuel to maintain anoverpressure of 5 kPa. Fuel escaping from the measuring device is conducted into thegraduated cylinders for measuring the volumetric flow through each hole of the nozzle.Themembrane deformation is assessed by strain gauges. They are glued to the membrane andforming the full Wheatstone’s bridge. We devoted special attention to the membrane shapeand temperature compensation of the strain gauges.

  13. Sarilumab Injection

    Science.gov (United States)

    ... the needle. Do not try to warm the medication by heating it in a microwave, placing it in warm water or in direct sunlight, or through any other method.Before injecting, check the prefilled syringe to be sure that the expiration date printed on the package has not passed. Look ...

  14. Enfuvirtide Injection

    Science.gov (United States)

    ... inject enfuvirtide into any skin that has a tattoo, scar, bruise, mole, a burn site, or has ... Enfuvirtide may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away: itching, swelling, pain, tingling, discomfort, ...

  15. Fluorouracil Injection

    Science.gov (United States)

    ... of a doctor who is experienced in giving chemotherapy medications for cancer. Treatment with fluorouracil injection may cause serious side effects. ... this medication.If you experience a serious side effect, you or your doctor ... (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/ ...

  16. Lanreotide Injection

    Science.gov (United States)

    Lanreotide injection is used to treat people with acromegaly (condition in which the body produces too much growth hormone, causing enlargement of the hands, feet, and facial features; joint pain; and other symptoms) who have not successfully, or cannot be treated ...

  17. Paliperidone Injection

    Science.gov (United States)

    ... the body slow movements or shuffling walk painful erection of the penis that lasts for hours cough, chills and/or other signs of infection Paliperidone injection may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.If you experience a ...

  18. Ziprasidone Injection

    Science.gov (United States)

    ... stiffness falling confusion sweating loss of consciousness painful erection of the penis that lasts for hours Ziprasidone injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.If you experience a ...

  19. Risperidone Injection

    Science.gov (United States)

    ... control slow movements or shuffling walk falling painful erection of the penis that lasts for hours Risperidone extended-release injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.If you experience a ...

  20. [Ceramic-on-ceramic bearings in total hip arthroplasty (THA)].

    Science.gov (United States)

    Sentürk, U; Perka, C

    2015-04-01

    The main reason for total hip arthroplasty (THA) revision is the wear-related aseptic loosening. Younger and active patients after total joint replacement create high demands, in particular, on the bearings. The progress, especially for alumina ceramic-on-ceramic bearings and mixed ceramics have solved many problems of the past and lead to good in vitro results. Modern ceramics (alumina or mixed ceramics containing alumina) are extremely hard, scratch-resistant, biocompatible, offer a low coefficient of friction, superior lubrication and have the lowest wear rates in comparison to all other bearings in THA. The disadvantage of ceramic is the risk of material failure, i.e., of ceramic fracture. The new generation of mixed ceramics (delta ceramic), has reduced the risk of head fractures to 0.03-0.05 %, but the risk for liner fractures remains unchanged at about 0.02 %. Assuming a non-impinging component implantation, ceramic-on-ceramic bearings have substantial advantages over all other bearings in THA. Due to the superior hardness, ceramic bearings produce less third body wear and are virtually impervious to damage from instruments during the implantation process. A specific complication for ceramic-on-ceramic bearings is "squeaking". The high rate of reported squeaking (0.45 to 10.7 %) highlights the importance of precise implant positioning and the stem and patient selection. With precise implant positioning this problem is rare with many implant designs and without clinical relevance. The improved tribology and the presumable resulting implant longevity make ceramic-on-ceramic the bearing of choice for young and active patients. Georg Thieme Verlag KG Stuttgart · New York.

  1. Recent Developments and Trends in Powder Injection Molding

    Institute of Scientific and Technical Information of China (English)

    Hermina Wang

    2000-01-01

    Injection molding is a productive and widely used technology for shaping plastics. The use of this shaping technique to metal and ceramics powders is termed powder injection molding (PIM). This process combines a certain quantity of a polymer with a metallic or ceramic powder to form a feedstock that can be molded. After shaping, the polymeric binder is extracted and the powder is sintered. When proper powder size or/and its distribution are used, sintered densities of 95% or more, often to near-theoretical densities, are reached and the mechanical properties are, therefore, generally superior to those of traditional PM parts.

  2. Testing method for ceramic armor and bare ceramic tiles

    NARCIS (Netherlands)

    Carton, E.P.; Roebroeks, G.H.J.J.

    2014-01-01

    TNO has developed an alternative, more configuration independent ceramic test method than the standard Depth-of-Penetration test method. In this test ceramic tiles and ceramic based armor are evaluated as target without a semi-infinite backing layer. An energy approach is chosen to evaluate and rank

  3. Testing method for ceramic armour and bare ceramic tiles

    NARCIS (Netherlands)

    Carton, E.P.; Roebroeks, G.H.J.J.

    2016-01-01

    TNO developed an alternative, more configuration independent ceramic test method than the Depth-of-Penetration test method. In this alternative test ceramic tiles and ceramic based armour are evaluated as target without a semi-infinite backing layer. An energy approach is chosen to evaluate and rank

  4. Testing method for ceramic armor and bare ceramic tiles

    NARCIS (Netherlands)

    Carton, E.P.; Roebroeks, G.H.J.J.

    2014-01-01

    TNO has developed an alternative, more configuration independent ceramic test method than the standard Depth-of-Penetration test method. In this test ceramic tiles and ceramic based armor are evaluated as target without a semi-infinite backing layer. An energy approach is chosen to evaluate and rank

  5. Testing method for ceramic armour and bare ceramic tiles

    NARCIS (Netherlands)

    Carton, E.P.; Roebroeks, G.H.J.J.

    2016-01-01

    TNO developed an alternative, more configuration independent ceramic test method than the Depth-of-Penetration test method. In this alternative test ceramic tiles and ceramic based armour are evaluated as target without a semi-infinite backing layer. An energy approach is chosen to evaluate and rank

  6. Cooled Ceramic Turbine Vane Project

    Data.gov (United States)

    National Aeronautics and Space Administration — N&R Engineering will investigate the feasibility of cooled ceramics, such as ceramic matrix composite (CMC) turbine blade concepts that can decrease specific...

  7. Adhesion of Streptococcus mutans to various dental materials in a laminar flow chamber system.

    Science.gov (United States)

    Rosentritt, Martin; Hahnel, Sebastian; Gröger, Gerhard; Mühlfriedel, Bastian; Bürgers, Ralf; Handel, Gerhard

    2008-07-01

    Newly developed dental materials have to be tested for their susceptibility to adhere bacteria causing caries and periodontitis. The objective of this study was to establish an in vitro laminar flow chamber assay for dental material evaluation with regard to the adhesion of oral bacteria. Test specimens of commonly used dental materials (ceramic (five brands of ceramics, n = 15/brand), composite (eight brands of composites, n = 15/brand), and alloy (two brands of alloys, n = 15/brand) specimens) were inserted in a laminar flow chamber system and rinsed with artificial saliva (2 h) and Streptococcus mutans NCTC 10,449 suspension (4 h) successively. The amount of adhered bacteria was quantified using a Resazurin reduction assay (Alamar Blue). Statistical analysis was performed using the Mann-Whitney U-test (alpha = 0.05). Regarding adhesion of Streptococcus mutans, significant differences between the various material classes were found. Highest fluorescence values (ranging from 973 to 3145), correlating with high bacterial adhesion, were found on composite samples, and lowest values (173-272) were found on the alloys. Ceramic specimens showed an intermediate adhesion of Streptococcus mutans (fluorescence values from 532 to 1326). Streptococcus mutans NCTC 10449 adhered differently to the various classes of dental materials. The established laminar flow chamber device provides a suitable method for evaluating the adhesion of oral bacteria to dental material surfaces. 2007 Wiley Periodicals, Inc.

  8. Plasma chemistry in wire chambers

    Energy Technology Data Exchange (ETDEWEB)

    Wise, J.

    1990-05-01

    The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an {sup 55}Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed.

  9. OVA-specific CD8(+)T cells do not express granzyme B during anterior chamber associated immune deviation

    NARCIS (Netherlands)

    Ren, Y.; Yang, P.; Li, B.; Gao, Y.; Zhou, H.; Huang, X.; Zhu, L.; Kijlstra, A.

    2006-01-01

    To examine antigen (Ag)-specific CTL response during anterior chamber associated immune deviation (ACAID). Methods OVA or OVA257-264 peptide was injected into the anterior chamber (AC) of C57BL/6 mice. There were 16 mice in each ACAID group induced with OVA or OVA257-264 peptide. The mice were

  10. Rolling contact fatigue of ceramics

    OpenAIRE

    Hadfield, Mark

    1993-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. Ceramic/ceramic and ceramic/steel contacts under lubricated rolling conditions are studied. This work is of interest to ball bearing manufacturers as the use of ceramics in the design of these components has some advantages over traditional bearing-steel materials. Low density and increased stiffness are the mechanical properties which gas-turbine and machine tool manufacturers are most likel...

  11. OXYGEN TRANSPORT CERAMIC MEMBRANES

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2000-10-01

    This is the third quarterly report on oxygen Transport Ceramic Membranes. In the following, the report describes the progress made by our university partners in Tasks 1 through 6, experimental apparatus that was designed and built for various tasks of this project, thermodynamic calculations, where applicable and work planned for the future. (Task 1) Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. (Task 2) Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. (Task 3) Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. (Task 4) Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. (Task 5) Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. (Task 6) Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

  12. FATIGUE OF DENTAL CERAMICS

    Science.gov (United States)

    Zhang, Yu; Sailer, Irena; Lawn, Brian R

    2013-01-01

    Objectives Clinical data on survival rates reveal that all-ceramic dental prostheses are susceptible to fracture from repetitive occlusal loading. The objective of this review is to examine the underlying mechanisms of fatigue in current and future dental ceramics. Data/sources The nature of various fatigue modes is elucidated using fracture test data on ceramic layer specimens from the dental and biomechanics literature. Conclusions Failure modes can change over a lifetime, depending on restoration geometry, loading conditions and material properties. Modes that operate in single-cycle loading may be dominated by alternative modes in multi-cycle loading. While post-mortem examination of failed prostheses can determine the sources of certain fractures, the evolution of these fractures en route to failure remains poorly understood. Whereas it is commonly held that loss of load-bearing capacity of dental ceramics in repetitive loading is attributable to chemically-assisted 'slow crack growth' in the presence of water, we demonstrate the existence of more deleterious fatigue mechanisms, mechanical rather than chemical in nature. Neglecting to account for mechanical fatigue can lead to gross overestimates in predicted survival rates. Clinical significance Strategies for prolonging the clinical lifetimes of ceramic restorations are proposed based on a crack-containment philosophy. PMID:24135295

  13. Diffusion in ceramics

    CERN Document Server

    Pelleg, Joshua

    2016-01-01

    This textbook provides an introduction to changes that occur in solids such as ceramics, mainly at high temperatures, which are diffusion controlled, as well as presenting research data. Such changes are related to the kinetics of various reactions such as precipitation, oxidation and phase transformations, but are also related to some mechanical changes, such as creep. The book is composed of two parts, beginning with a look at the basics of diffusion according to Fick's Laws. Solutions of Fick’s second law for constant D, diffusion in grain boundaries and dislocations are presented along with a look at the atomistic approach for the random motion of atoms. In the second part, the author discusses diffusion in several technologically important ceramics. The ceramics selected are monolithic single phase ones, including: A12O3, SiC, MgO, ZrO2 and Si3N4. Of these, three refer to oxide ceramics (alumina, magnesia and zirconia). Carbide based ceramics are represented by the technologically very important Si-ca...

  14. OXYGEN TRANSPORT CERAMIC MEMBRANES

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2000-10-01

    This is the third quarterly report on oxygen Transport Ceramic Membranes. In the following, the report describes the progress made by our university partners in Tasks 1 through 6, experimental apparatus that was designed and built for various tasks of this project, thermodynamic calculations, where applicable and work planned for the future. (Task 1) Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. (Task 2) Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. (Task 3) Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. (Task 4) Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. (Task 5) Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. (Task 6) Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

  15. Ceramic impregnated superabrasives

    Science.gov (United States)

    Radtke, Robert P.; Sherman, Andrew

    2009-02-10

    A superabrasive fracture resistant compact is formed by depositing successive layers of ceramic throughout the network of open pores in a thermally stable self-bonded polycrystalline diamond or cubic boron nitride preform. The void volume in the preform is from approximately 2 to 10 percent of the volume of the preform, and the average pore size is below approximately 3000 nanometers. The preform is evacuated and infiltrated under at least about 1500 pounds per square inch pressure with a liquid pre-ceramic polymerizable precursor. The precursor is infiltrated into the preform at or below the boiling point of the precursor. The precursor is polymerized into a solid phase material. The excess is removed from the outside of the preform, and the polymer is pyrolized to form a ceramic. The process is repeated at least once more so as to achieve upwards of 90 percent filling of the original void volume. When the remaining void volume drops below about 1 percent the physical properties of the compact, such as fracture resistance, improve substantially. Multiple infiltration cycles result in the deposition of sufficient ceramic to reduce the void volume to below 0.5 percent. The fracture resistance of the compacts in which the pores are lined with formed in situ ceramic is generally at least one and one-half times that of the starting preforms.

  16. Fatigue of dental ceramics.

    Science.gov (United States)

    Zhang, Yu; Sailer, Irena; Lawn, Brian R

    2013-12-01

    Clinical data on survival rates reveal that all-ceramic dental prostheses are susceptible to fracture from repetitive occlusal loading. The objective of this review is to examine the underlying mechanisms of fatigue in current and future dental ceramics. The nature of various fatigue modes is elucidated using fracture test data on ceramic layer specimens from the dental and biomechanics literature. Failure modes can change over a lifetime, depending on restoration geometry, loading conditions and material properties. Modes that operate in single-cycle loading may be dominated by alternative modes in multi-cycle loading. While post-mortem examination of failed prostheses can determine the sources of certain fractures, the evolution of these fractures en route to failure remains poorly understood. Whereas it is commonly held that loss of load-bearing capacity of dental ceramics in repetitive loading is attributable to chemically assisted 'slow crack growth' in the presence of water, we demonstrate the existence of more deleterious fatigue mechanisms, mechanical rather than chemical in nature. Neglecting to account for mechanical fatigue can lead to gross overestimates in predicted survival rates. Strategies for prolonging the clinical lifetimes of ceramic restorations are proposed based on a crack-containment philosophy. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Mechanical properties of ceramics

    CERN Document Server

    Pelleg, Joshua

    2014-01-01

    This book discusses the mechanical properties of ceramics and aims to provide both a solid background for undergraduate students, as well as serving as a text to bring practicing engineers up to date with the latest developments in this topic so they can use and apply these to their actual engineering work.  Generally, ceramics are made by moistening a mixture of clays, casting it into desired shapes and then firing it to a high temperature, a process known as 'vitrification'. The relatively late development of metallurgy was contingent on the availability of ceramics and the know-how to mold them into the appropriate forms. Because of the characteristics of ceramics, they offer great advantages over metals in specific applications in which hardness, wear resistance and chemical stability at high temperatures are essential. Clearly, modern ceramics manufacturing has come a long way from the early clay-processing fabrication method, and the last two decades have seen the development of sophisticated technique...

  18. Subcutaneous (SQ) injections

    Science.gov (United States)

    SQ injections; Sub-Q injections; Diabetes subcutaneous injection; Insulin subcutaneous injection ... NIH. Giving a subcutaneous injection . Rockville, MD. National ... of Health and Human Services NIH publications; 2015. Available ...

  19. "Flat-Fish" Vacuum Chamber

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

    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.

  20. Impedances of Laminated Vacuum Chambers

    Energy Technology Data Exchange (ETDEWEB)

    Burov, A.; Lebedev, V.; /Fermilab

    2011-06-22

    First publications on impedance of laminated vacuum chambers are related to early 70s: those are of S. C. Snowdon [1] and of A. G. Ruggiero [2]; fifteen years later, a revision paper of R. Gluckstern appeared [3]. All the publications were presented as Fermilab preprints, and there is no surprise in that: the Fermilab Booster has its laminated magnets open to the beam. Being in a reasonable mutual agreement, these publications were all devoted to the longitudinal impedance of round vacuum chambers. The transverse impedance and the flat geometry case were addressed in more recent paper of K. Y. Ng [4]. The latest calculations of A. Macridin et al. [5] revealed some disagreement with Ref. [4]; this fact stimulated us to get our own results on that matter. Longitudinal and transverse impendances are derived for round and flat laminated vacuum chambers. Results of this paper agree with Ref. [5].

  1. The CLAS drift chamber system

    CERN Document Server

    Mestayer, M D; Asavapibhop, B; Barbosa, F J; Bonneau, P; Christo, S B; Dodge, G E; Dooling, T; Duncan, W S; Dytman, S A; Feuerbach, R; Gilfoyle, G P; Gyurjyan, V; Hicks, K H; Hicks, R S; Hyde-Wright, C E; Jacobs, G; Klein, A; Klein, F J; Kossov, M; Kuhn, S E; Magahiz, R A; Major, R W; Martin, C; McGuckin, T; McNabb, J; Miskimen, R A; Müller, J A; Niczyporuk, B B; O'Meara, J E; Qin, L M; Raue, B A; Robb, J; Roudot, F; Schumacher, R A; Tedeschi, D J; Thompson, R A; Tilles, D; Tuzel, W; Vansyoc, K; Vineyard, M F; Weinstein, L B; Wilkin, G R; Yegneswaran, A; Yun, J

    2000-01-01

    Experimental Hall B at Jefferson Laboratory houses the CEBAF Large Acceptance Spectrometer, the magnetic field of which is produced by a superconducting toroid. The six coils of this toroid divide the detector azimuthally into six sectors, each of which contains three large multi-layer drift chambers for tracking charged particles produced from a fixed target on the toroidal axis. Within the 18 drift chambers are a total of 35,148 individually instrumented hexagonal drift cells. The novel geometry of these chambers provides for good tracking resolution and efficiency, along with large acceptance. The design and construction challenges posed by these large-scale detectors are described, and detailed results are presented from in-beam measurements.

  2. Assessment of ceramic membrane filters

    Energy Technology Data Exchange (ETDEWEB)

    Ahluwalia, R.K.; Geyer, H.K.; Im, K.H. [and others

    1995-08-01

    The objectives of this project include the development of analytical models for evaluating the fluid mechanics of membrane coated, dead-end ceramic filters, and to determine the effects of thermal and thermo-chemical aging on the material properties of emerging ceramic hot gas filters. A honeycomb cordierite monolith with a thin ceramic coating and a rigid candle filter were evaluated.

  3. Ceramic composites: Enabling aerospace materials

    Science.gov (United States)

    Levine, S. R.

    1992-01-01

    Ceramics and ceramic matrix composites (CMC) have the potential for significant impact on the performance of aerospace propulsion and power systems. In this paper, the potential benefits are discussed in broad qualitative terms and are illustrated by some specific application case studies. The key issues in need of resolution for the potential of ceramics to be realized are discussed.

  4. Annular-Cross-Section CFE Chamber

    Science.gov (United States)

    Sharnez, Rizwan; Sammons, David W.

    1994-01-01

    Proposed continuous-flow-electrophoresis (CFE) chamber of annular cross section offers advantages over conventional CFE chamber, and wedge-cross-section chamber described in "Increasing Sensitivity in Continuous-Flow Electrophoresis" (MFS-26176). In comparison with wedge-shaped chamber, chamber of annular cross section virtually eliminates such wall effects as electro-osmosis and transverse gradients of velocity. Sensitivity enhanced by incorporating gradient maker and radial (collateral) flow.

  5. Ionization chambers for LET determination

    DEFF Research Database (Denmark)

    Kaiser, Franz-Joachim; Bassler, Niels; Tölli, Heikki

    2010-01-01

    resolution and high sensitivity are necessary. For exact dosimetry which is done using ionization chambers (ICs), the recombination taking place in the IC has to be known. Up to now, recombination is corrected phenomenologically and more practical approaches are currently used. Nevertheless, Jaff´e's theory...... of columnar recombination was designed to model the detector efficiency of an ionization chamber. Here, we have shown that despite the approximations and simplification made, the theory is correct for the LETs typically found in clinical radiotherapy employing particles from protons to carbon ions...

  6. Ionization Chamber Measures Extreme Ultraviolet

    Science.gov (United States)

    Carlson, Robert W.

    1987-01-01

    Ionization chamber operates in nearly total photon absorption as stable, self-calibrating detector of ionizing extreme ultraviolet radiation. Working gas of instrument is neon; photoionization properties well known and readily applicable to absolute measurements. Designed for measurements of solar ultraviolet flux aboard sounding rocket, instrument used on Earth to measure ultraviolet radiation in vacuum systems. Ionization chamber collects positive neon ions and electrons produced by irradiation of neon gas by ultraviolet photons. Approximately one ion produced by each photon; consequently, photoionization current nearly proportional to photon flux.

  7. Advanced Ceramics from Preceramic Polymers Modified at the Nano-Scale: A Review

    Directory of Open Access Journals (Sweden)

    Enrico Bernardo

    2014-03-01

    Full Text Available Preceramic polymers, i.e., polymers that are converted into ceramics upon heat treatment, have been successfully used for almost 40 years to give advanced ceramics, especially belonging to the ternary SiCO and SiCN systems or to the quaternary SiBCN system. One of their main advantages is the possibility of combining the shaping and synthesis of ceramics: components can be shaped at the precursor stage by conventional plastic-forming techniques, such as spinning, blowing, injection molding, warm pressing and resin transfer molding, and then converted into ceramics by treatments typically above 800 °C. The extension of the approach to a wider range of ceramic compositions and applications, both structural and thermo-structural (refractory components, thermal barrier coatings or functional (bioactive ceramics, luminescent materials, mainly relies on modifications of the polymers at the nano-scale, i.e., on the introduction of nano-sized fillers and/or chemical additives, leading to nano-structured ceramic components upon thermal conversion. Fillers and additives may react with the main ceramic residue of the polymer, leading to ceramics of significant engineering interest (such as silicates and SiAlONs, or cause the formation of secondary phases, significantly affecting the functionalities of the polymer-derived matrix.

  8. Environment Conscious Ceramics (Ecoceramics)

    Science.gov (United States)

    Singh, Mrityunjay; Levine, Stanley R. (Technical Monitor)

    2000-01-01

    Environment conscious ceramics (Ecoceramics) are a new class of materials, which can be produced with renewable natural resources (wood) or wood wastes (wood sawdust). Silicon carbide-based ecoceramics have been fabricated by reactive infiltration of carbonaceous preforms by molten silicon or silicon-refractory metal alloys. These carbonaceous preforms have been fabricated by pyrolysis of solid wood bodies at 1000 C. The fabrication approach, microstructure, and mechanical properties of SiC-based ecoceramics are presented. Ecoceramics have tailorable properties and behave like ceramic materials manufactured by conventional approaches.

  9. Displacive Transformation in Ceramics

    Science.gov (United States)

    1994-02-28

    single cycle[21]. In zirconia , ferroelastic domains appeared during the cubic to tetragonal transformation at -2200’C, where [c] axes were elongated...Mechanism in Tetragonal Zirconia ( TZP ) Ceramics," Adv. in Ceramics 24 (1986) 653-662. 26. K. Mehta, J. F. Jue and A. V. Virkar, "Grinding-Liduced...barium copper oxide (YBa2Cu306+x) and dicalcium silicate (Ca 2 SiO4 ). The cubic to tetragonal transformation in PbTiO3 40 was proven to be

  10. Influence of Reduced Mass Flow Rate and Chamber Backpressure on Swirl Injector Fluid Mechanics

    Science.gov (United States)

    Kenny, R Jeremy; Hulka, James R.

    2008-01-01

    Industry interest in variable-thrust liquid rocket engines places a demand on engine injector technology to operate over a wide range of liquid mass flow rates and chamber backpressures. One injection technology of current interest for variable thrust applications is an injector design with swirled fluids. Current swirl injector design methodologies do not take into account how swirl injector design parameters respond to elevated chamber backpressures at less than design mass flow rates. The current work was created to improve state-of-the-art swirl injector design methods in this area. The specific objective was to study the effects of elevated chamber backpressure and off-design mass flow rates on swirl injector fluid mechanics. Using a backpressure chamber with optical access, water was flowed through a swirl injector at various combinations of chamber backpressure and mass flow rates. The film thickness profile down the swirl injector nozzle section was measured through a transparent nozzle section of the injector. High speed video showed measurable increases in the film thickness profile with application of chamber backpressure and mass flow rates less than design. At prescribed combinations of chamber backpressure and injected mass flow rate, a discrete change in the film thickness profile was observed. Measured injector discharge coefficient values showed different trends with increasing chamber backpressure at low mass flow rates as opposed to near-design mass flow rates. Downstream spray angles showed classic changes in morphology as the mass flow rate was decreased below the design value. Increasing chamber backpressure decreased the spray angle at any injection mass flow rate. Experimental measurements and discussion of these results are reported in this paper.

  11. Influence of Reduced Mass Flow Rate and Chamber Backpressure on Swirl Injector Fluid Mechanics

    Science.gov (United States)

    Kenny, R Jeremy; Hulka, James R.

    2008-01-01

    Industry interest in variable-thrust liquid rocket engines places a demand on engine injector technology to operate over a wide range of liquid mass flow rates and chamber backpressures. One injection technology of current interest for variable thrust applications is an injector design with swirled fluids. Current swirl injector design methodologies do not take into account how swirl injector design parameters respond to elevated chamber backpressures at less than design mass flow rates. The current work was created to improve state-of-the-art swirl injector design methods in this area. The specific objective was to study the effects of elevated chamber backpressure and off-design mass flow rates on swirl injector fluid mechanics. Using a backpressure chamber with optical access, water was flowed through a swirl injector at various combinations of chamber backpressure and mass flow rates. The film thickness profile down the swirl injector nozzle section was measured through a transparent nozzle section of the injector. High speed video showed measurable increases in the film thickness profile with application of chamber backpressure and mass flow rates less than design. At prescribed combinations of chamber backpressure and injected mass flow rate, a discrete change in the film thickness profile was observed. Measured injector discharge coefficient values showed different trends with increasing chamber backpressure at low mass flow rates as opposed to near-design mass flow rates. Downstream spray angles showed classic changes in morphology as the mass flow rate was decreased below the design value. Increasing chamber backpressure decreased the spray angle at any injection mass flow rate. Experimental measurements and discussion of these results are reported in this paper.

  12. Fiber Volume Fraction Influence on Fiber Compaction in Tapered Resin Injection Pultrusion Manufacturing

    Science.gov (United States)

    Masuram, N. B.; Roux, J. A.; Jeswani, A. L.

    2016-06-01

    Liquid resin is injected into the tapered injection chamber through the injection slots to completely wetout the fiber reinforcements in a resin injection pultrusion process. As the resin penetrates through the fibers, the resin also pushes the fibers away from the wall towards the centerline causing compaction of the fiber reinforcements. The fibers are squeezed together due to compaction, making resin penetration more difficult; thus higher resin injection pressures are required to effectively penetrate through the fibers and achieve complete wetout. Fiber volume fraction in the final pultruded composite is a key to decide the mechanical and/or chemical properties of the composite. If the fiber volume fraction is too high, more fibers are squeezed together creating a fiber lean region near the wall and fiber rich region away from the wall. Also, the design of the injection chamber significantly affects the minimum injection pressure required to completely wet the fibers. A tapered injection chamber is considered such that wetout occurs at lower injection pressures due to the taper angle of the injection chamber. In this study, the effect of fiber volume fraction on the fiber reinforcement compaction and complete fiber wetout for a tapered injection chamber is investigated.

  13. DELPHI's Ring Imaging Cherenkov Chamber

    CERN Multimedia

    1989-01-01

    The hundreds of mirrors around this Ring Imaging Cherenkov Chamber reflect cones of light created by fast moving particles to a detector. The velocity of a particle can be measured by the size of the ring produced on the detector. DELPHI, which ran from 1989 to 2000 on the LEP accelerator, was primarily concerned with particle identification.

  14. A dual deformable reverberation chamber

    NARCIS (Netherlands)

    Leferink, Frank

    2010-01-01

    There is disclosed an arrangement for measuring the effectiveness of a shielding material against electromagnetic fields. The arrangement comprises a first and a second reverberation chamber sharing a common wall. The common wall is partly made of the shielding material. A first antenna is arranged

  15. Bubble chamber: colour enhanced tracks

    CERN Multimedia

    1998-01-01

    This artistically-enhanced image of real particle tracks was produced in the Big European Bubble Chamber (BEBC). Liquid hydrogen is used to create bubbles along the paths of the particles as a piston expands the medium. A magnetic field is produced in the detector causing the particles to travel in spirals, allowing charge and momentum to be measured.

  16. Testing an hydrogen streamer chamber

    CERN Multimedia

    1975-01-01

    A 2x10 cm gap streamer chamber, 35x55 cm2 in surface, was built and tested at CERN. Good tracks of cosmic rays were obtained up to atmospheric pressure, see F. Rohrbach et al, CERN-LAL (Orsay) Collaboration, Nucl. Instr. Methods 141 (1977) 229. Michel Cathenoz stand on the center.

  17. Distorting the ceramic familiar: materiality and non-ceramic intervention, Conference, Keramik Museum, Germany

    OpenAIRE

    Livingstone, Andrew

    2009-01-01

    Invited conference speaker, Westerwald Keramik Museum, August 2009. Paper title: Distorting the ceramic familiar: materiality and non-ceramic intervention.\\ud \\ud This paper will examine the integration of non-ceramic media into the discourse of ceramics.

  18. Reinfiltration processes for polymer derived fiber reinforced ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Duran, A. [CSIC, Madrid (Spain). Inst. de Ceramica y Vidrio; Aparicio, M. [CSIC, Madrid (Spain). Inst. de Ceramica y Vidrio; Rebstock, K. [Daimler-Benz Aerospace AG, Friedrichshafen (Germany). Dornier Forschung; Vogel, W.D. [Daimler-Benz Aerospace AG, Friedrichshafen (Germany). Dornier Forschung

    1997-06-01

    Ceramic matrix composites (CMCs) are candidate materials for applications like reentry heat-shields for spacecrafts or turbine parts for aircrafts. Taylored mechanical properties, improved oxidation resistance and environmental stability are very important for these materials. To improve the performance of liquid polymer derived ceramic matrix composites (LPI-CMCs), different techniques for reducing porosity by reinfiltration are discussed. Reinfiltration processes have been performed on a carbon fiber reinforced SiC ceramic, using injection of suitable polymers and sol-gel sols. It has been demonstrated that both methods can reduce the porosity and increase the mechanical properties. Different parameters have been controlled including impregnation pressures and times, heat curing and initial porosity of the substrates as well as composition, viscosity and concentration of the infiltrating solution. The infiltrated samples were characterized by Hg porosimetry, interlaminar shear strength and SEM as well as by oxidation tests. (orig.)

  19. Shape forming of ceramics via gelcasting of aqueous particulate slurries

    Indian Academy of Sciences (India)

    S Dhara; R K Kamboj; M Pradhan; P Bhargava

    2002-11-01

    Gelcasting is a promising technique for shape forming of bulk dense or porous ceramic, metal structures. The process offers a number of advantages over processes such as slip casting, injection molding in forming complex ceramic shapes. It is shown here that the optimization of slurry rheology, choice of mold material, mold design and the drying conditions have a significant role in the overall success of the process. In this process, components of simple or complex shapes can be produced to near net shape by direct casting. If required complex shapes can also be produced by machining the green gelcast bodies. The process of gelcasting also has a lot of potential in forming highly porous ceramic shapes.

  20. Hydrostatic Hyperbaric Chamber Ventilation System

    Science.gov (United States)

    Sarguisingh, Miriam J.

    2012-01-01

    The hydrostatic hyperbaric chamber (HHC) represents the merger of several technologies in development for NASA aerospace applications, harnessed to directly benefit global health. NASA has significant experience developing composite hyperbaric chambers for a variety of applications. NASA also has researched the application of water-filled vessels to increase tolerance of acceleration forces. The combination of these two applications has resulted in the hydrostatic chamber, which has been conceived as a safe, affordable means of making hyperbaric oxygen therapy (HBOT) available in the developing world for the treatment of a variety of medical conditions. Specifically, HBOT is highly-desired as a possibly curative treatment for Buruli Ulcer, an infectious condition that afflicts children in sub-Saharan Africa. HBOT is simply too expensive and too dangerous to implement in the developing world using standard equipment. The HHC technology changes the paradigm. The HHC differs from standard hyperbaric chambers in that the majority of its volume is filled with water which is pressurized by oxygen being supplied in the portion of the chamber containing the patient s head. This greatly reduces the amount of oxygen required to sustain a hyperbaric atmosphere, thereby making the system more safe and economical to operate. An effort was taken to develop an HHC system to apply HBOT to children that is simple and robust enough to support transport, assembly, maintenance and operation in developing countries. This paper details the concept for an HHC ventilation and pressurization system to provide controlled pressurization and adequate washout of carbon dioxide while the subject is enclosed in the confined space during the administration of the medical treatment. The concept took into consideration operational complexity, safety to the patient and operating personnel, and physiological considerations. The simple schematic, comprised of easily acquired commercial hardware

  1. OXYGEN TRANSPORT CERAMIC MEMBRANES

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2001-05-01

    The mechanical properties of model systems were analyzed. A reasonably accurate finite element model was implemented and a rational metric to predict the strength of ceramic/metal concentrical joints was developed. The mode of failure of the ceramic/metal joints was determined and the importance of the mechanical properties of the braze material was assessed. Thermal cycling experiments were performed on the model systems and the results were discussed. Additionally, experiments using the concept of placing diffusion barriers on the ceramic surface to limit the extent of the reaction with the braze were performed. It was also observed that the nature and morphology of the reaction zone depends greatly on the nature of the perovskite structure being used. From the experiments, it is observed that the presence of Cr in the Fe-occupied sites decreases the tendency of Fe to segregate and to precipitate out of the lattice. In these new experiments, Ni was observed to play a major role in the decomposition of the ceramic substrate.

  2. Nanocrystalline and Nanoporous Ceramics

    NARCIS (Netherlands)

    Verweij, Henk

    1996-01-01

    Nanocrystalline and nanoporous ceramics, renowned for their special transport properties, have typical applications in the fields of energy, the environment, and separation technology. One example is a solid oxide fuel cell, where an anode with improved characteristics was obtained by an optimized n

  3. Transformation Toughening of Ceramics

    Science.gov (United States)

    1992-03-01

    chanical twing of ualaneeting Ceramica at High Temperatures. ILondo, Patigue-crack growth in overaged and partially stabi- U.K., 198.""IS. Itoribe... Ceramica " Chapter 18 In Mechanical Prop- ŗR. M. !AcMeeding and A. 0. Evans, ’Mechanics of Transformation ertles of Engineering Ceramics. Edited by W.W

  4. Statistic><Ceramics

    DEFF Research Database (Denmark)

    Hansen, Flemming Tvede

    2008-01-01

    Co-organizer for and participant at the exhibition: Statistic><Ceramics The Röhsska Museum of Design and Decorative Arts; Gothenborg 5/2-16/3 2008 Museum fur Kunst und Gewerbe, Hamburg 3/4-27/4 2008...

  5. Growing and Analyzing Biofilms in Flow Chambers

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim; Sternberg, Claus

    2011-01-01

    This unit describes the setup of flow chamber systems for the study of microbial biofilms, and methods for the analysis of structural biofilm formation. Use of flow chambers allows direct microscopic investigation of biofilm formation. The biofilms in flow chambers develop under hydrodynamic...... conditions, and the environment can be carefully controlled and easily changed. The protocols in this unit include construction of the flow chamber and the bubble trap, assembly and sterilization of the flow chamber system, inoculation of the flow chambers, running of the system, image capture and analysis...

  6. Laser beam active brazing of metal ceramic joints

    Science.gov (United States)

    Haferkamp, Heinz; Bach, Friedrich W.; von Alvensleben, Ferdinand; Kreutzburg, K.

    1996-04-01

    The use of engineering ceramics is becoming more and more important. Reasons for this are the specific properties of these materials, such as high strength, corrosion resistance and wear resistance. To apply the advantages of ceramics, joining techniques of metal ceramic parts are required. In this paper, joining of metal ceramic joints by laser beam brazing is presented. This joining technique is characterized by local heat input, and the minimal thermal stress of the brazed components. During the investigations, an Nd:YAG laser and a vacuum chamber were applied. The advantages of Nd:YAG lasers are the simple mechanical construction, and laser beam guidance via quartz glass fibers, which leads to high handling flexibility. In addition, most of the materials show a high absorption rate for this kind of radiation. As materials, ceramic Al2O3 with a purity of 99.4% and metals such as X5CrNi189 and Fe54Ni29Co17 were used. As a filler material, commercially available silver and silver- copper brazes with chemically active elements like titanium were employed. During this study, the brazing wetting behavior and the formation of diffusion layers in dependence on processing parameters were investigated. The results have shown that high brazing qualities can be achieved by means of the laser beam brazing process. Crack-free joining of metal ceramic parts is currently only possible by the use of metals such as Fe54Ni29Co17 because of its low thermal expansion coefficient, which reduces thermal stresses within the joining zone.

  7. Ceramic tubesheet design analysis

    Energy Technology Data Exchange (ETDEWEB)

    Mallett, R.H.; Swindeman, R.W.

    1996-06-01

    A transport combustor is being commissioned at the Southern Services facility in Wilsonville, Alabama to provide a gaseous product for the assessment of hot-gas filtering systems. One of the barrier filters incorporates a ceramic tubesheet to support candle filters. The ceramic tubesheet, designed and manufactured by Industrial Filter and Pump Manufacturing Company (EF&PM), is unique and offers distinct advantages over metallic systems in terms of density, resistance to corrosion, and resistance to creep at operating temperatures above 815{degrees}C (1500{degrees}F). Nevertheless, the operational requirements of the ceramic tubesheet are severe. The tubesheet is almost 1.5 m in (55 in.) in diameter, has many penetrations, and must support the weight of the ceramic filters, coal ash accumulation, and a pressure drop (one atmosphere). Further, thermal stresses related to steady state and transient conditions will occur. To gain a better understanding of the structural performance limitations, a contract was placed with Mallett Technology, Inc. to perform a thermal and structural analysis of the tubesheet design. The design analysis specification and a preliminary design analysis were completed in the early part of 1995. The analyses indicated that modifications to the design were necessary to reduce thermal stress, and it was necessary to complete the redesign before the final thermal/mechanical analysis could be undertaken. The preliminary analysis identified the need to confirm that the physical and mechanical properties data used in the design were representative of the material in the tubesheet. Subsequently, few exploratory tests were performed at ORNL to evaluate the ceramic structural material.

  8. Ceramic Laser Materials

    Energy Technology Data Exchange (ETDEWEB)

    Soules, T F; Clapsaddle, B J; Landingham, R L; Schaffers, K I

    2005-02-15

    Transparent ceramic materials have several major advantages over single crystals in laser applications, not the least of which is the ability to make large aperture parts in a robust manufacturing process. After more than a decade of working on making transparent YAG:Nd, Japanese workers have recently succeeded in demonstrating samples that performed as laser gain media as well as their single crystal counterparts. Since then several laser materials have been made and evaluated. For these reasons, developing ceramic laser materials is the most exciting and futuristic materials topic in today's major solid-state laser conferences. We have established a good working relationship with Konoshima Ltd., the Japanese producer of the best ceramic laser materials, and have procured and evaluated slabs designed by us for use in our high-powered SSHCL. Our measurements indicate that these materials will work in the SSHCL, and we have nearly completed retrofitting the SSHCL with four of the largest transparent ceramic YAG:Nd slabs in existence. We have also begun our own effort to make this material and have produced samples with various degrees of transparency/translucency. We are in the process of carrying out an extensive design-of-experiments to establish the significant process variables for making transparent YAG. Finally because transparent ceramics afford much greater flexibility in the design of lasers, we have been exploring the potential for much larger apertures, new materials, for example for the Mercury laser, other designs for SSHL, such as, edge pumping designs, slabs with built in ASE suppression, etc. This work has just beginning.

  9. Effects of Starch on Properties of Alumina-based Ceramic Cores

    Directory of Open Access Journals (Sweden)

    LI Fengguang

    2016-12-01

    Full Text Available In order to improve the poor leachability of alumina-based ceramic cores, different amount of starch was added to the specimens as pore former. Alumina-based ceramic cores were prepared by hot injection technology using corundum powder as base material, paraffin wax and beeswax as plasticizer, silica powder and magnesium oxide powder as mineralizing agent, wherein the parameters of the hot injection process were as follows:temperature of the slurry was 90℃, hot injection pressure was 0.5 MPa and holding time was 25 s. The effects of starch content on the properties of alumina-based ceramic cores were studied and discussed. The results indicate that during sintering period, the loss of starch in the specimens makes porosity of the alumina-based ceramic cores increase. When starch content increases, the room-temperature flexural strength of the ceramic cores reduces and the apparent porosity increases; the volatile solvent increases and the bulk density decreases. After being sintered at 1560℃ for 2.5 h, room-temperature flexural strength of the alumina-based ceramic cores with starch content of 8%(mass fraction is 24.8 MPa, apparent porosity is 47.98% when the volatile solvent is 1.92 g/h and bulk density is 1.88 g/cm3, the complex properties are optimal.

  10. A portable miniature anechoic chamber

    Science.gov (United States)

    Lorthioir, Jack; Gavin, Paul

    The portable miniature anechoic chamber (PMAC), a low-cost alternative to a full-size anechoic chamber, is presented. The PMAC is a miniature, enclosed, RF-tight microwave antenna range, which approximates the performance of an indoor range over the C through Ku (G through J)-band frequencies. The small footprint, four by six feet, allows for ease of movement by one person to a test site, indoors or outdoors. The PMAC can be used at I (intermediate)-level to support the operational readiness (OR) requirements of the U.S. Army, Navy or Air Force. In conjunction with the antenna test equipment (ATE), and under TPS control, it can be used for performance verification, fault detection and fault isolation. A typical application using the PMAC in this operating mode is described.

  11. Development of multiwire proportional chambers

    CERN Multimedia

    Charpak, G

    1969-01-01

    It has happened quite often in the history of science that theoreticians, confronted with some major difficulty, have successfully gone back thirty years to look at ideas that had then been thrown overboard. But it is rare that experimentalists go back thirty years to look again at equipment which had become out-dated. This is what Charpak and his colleagues did to emerge with the 'multiwire proportional chamber' which has several new features making it a very useful addition to the armoury of particle detectors. In the 1930s, ion-chambers, Geiger- Muller counters and proportional counters, were vital pieces of equipment in nuclear physics research. Other types of detectors have since largely replaced them but now the proportional counter, in new array, is making a comeback.

  12. Actuator System with Dual Chambers

    DEFF Research Database (Denmark)

    2015-01-01

    (8), the lid having a shaft opening (17) for a shaft (6) coupled to the magnetic rotor (5), wherein the magnetic rotor (5), when inserted in the translator cylinder (2), is arranged to translate a linear movement of the translator cylinder (2) into a rotational movement of the magnetic rotor by using...... magnetic flux (82) interacting between the magnetic stator and the magnetic rotor, said rotational movements is being transferred through a shaft (6), the lid (8) with a shaft opening (17) arranged for receiving the shaft (6), wherein the shaft is arranged to make both the linear and the rotational...... movement in the shaft opening (17), the lid (8) being arranged for confining the second end (15) of the translator cylinder (2), the translator cylinder confined by the lid (8) forms,when divided by the magnetic rotor (5), a first chamber (TC) with a first volume and a second chamber(BC) with a second...

  13. Actuator System with Dual Chambers

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to an actuator system with a magnetic lead screw (50), comprises a magnetic rotor (5) and a translator cylinder (2), the translator cylinder (2) comprises a magnetic stator (16), the translator cylinder (2) has a closed first end (14) and a second end confined by a lid...... (8), the lid having a shaft opening (17) for a shaft (6) coupled to the magnetic rotor (5), wherein the magnetic rotor (5), when inserted in the translator cylinder (2), is arranged to translate a linear movement of the translator cylinder (2) into a rotational movement of the magnetic rotor by using...... movement in the shaft opening (17), the lid (8) being arranged for confining the second end (15) of the translator cylinder (2), the translator cylinder confined by the lid (8) forms,when divided by the magnetic rotor (5), a first chamber (TC) with a first volume and a second chamber(BC) with a second...

  14. Microcontroller-driven fluid-injection system for atomic force microscopy.

    Science.gov (United States)

    Kasas, S; Alonso, L; Jacquet, P; Adamcik, J; Haeberli, C; Dietler, G

    2010-01-01

    We present a programmable microcontroller-driven injection system for the exchange of imaging medium during atomic force microscopy. Using this low-noise system, high-resolution imaging can be performed during this process of injection without disturbance. This latter circumstance was exemplified by the online imaging of conformational changes in DNA molecules during the injection of anticancer drug into the fluid chamber.

  15. MPS II drift chamber system

    Energy Technology Data Exchange (ETDEWEB)

    Platner, E.D.

    1982-01-01

    The MPS II detectors are narrow drift space chambers designed for high position resolution in a magnetic field and in a very high particle flux environment. Central to this implementation was the development of 3 multi-channel custom IC's and one multi-channel hybrid. The system is deadtimeless and requires no corrections on an anode-to-anode basis. Operational experience and relevance to ISABELLE detectors is discussed.

  16. Ceramic Stereolithography: Additive Manufacturing for Ceramics by Photopolymerization

    Science.gov (United States)

    Halloran, John W.

    2016-07-01

    Ceramic stereolithography and related additive manufacturing methods involving photopolymerization of ceramic powder suspensions are reviewed in terms of the capabilities of current devices. The practical fundamentals of the cure depth, cure width, and cure profile are related to the optical properties of the monomer, ceramic, and photo-active components. Postpolymerization steps, including harvesting and cleaning the objects, binder burnout, and sintering, are discussed and compared with conventional methods. The prospects for practical manufacturing are discussed.

  17. FIBROUS CERAMIC-CERAMIC COMPOSITE MATERIALS PROCESSING AND PROPERTIES

    OpenAIRE

    1986-01-01

    The introduction of continuous fibers in a ceramic matrix can improve its toughness, if the fiber-matrix bonding is weak enough, due to matrix microcracking and fiber pull-out. Ceramic-ceramic composite materials are processed according to liquid or gas phase techniques. The most important are made of glass, carbide, nitride or oxide matrices reinforced with carbon, SiC or Al2O3 fibers.

  18. GBO RF Anechoic Chamber & Antenna Test Range

    Data.gov (United States)

    Federal Laboratory Consortium — A shielded anechoic chamber measuring 15 by 15 by 37 feet is located in the Jansky Laboratory at Green Bank. This chamber has been outfitted as a far-field antenna...

  19. Experimental Investigation on Active Cooling for Ceramic Matrix Composite

    Institute of Scientific and Technical Information of China (English)

    PENG Li-na; HE Guo-qiang; LIU Pei-jin

    2009-01-01

    Compared with conventional materials, the active cooling ceramic matrix composite used in ramjet or scramjet makes their structures lighter in mass and better in performance. In this paper, an active and a passive cooling refractory composite specimens are designed and tested with an experimental facility composed of multilayer smale scale cooling penel which consists of a water cooling system and a ceramic matrix composite specimen, and a gas generator used for providing lower and higher transfer rate gases to simulate the temperatures in combustion chamber of ramjst. The active cooling specimen can continuously suffer high surface temperature of 2 000K for 30s and that of 3 000 K for 9.3 s, respectively. The experiment results show that the active cooling composite structure is available for high-temperature condition in ramjet.

  20. Study of a ceramic burner for shaftless stoves

    Institute of Scientific and Technical Information of China (English)

    Fang-qin Dai; Suo-yi Huang; Shao-hua Li; Ke Liu

    2009-01-01

    A multi-burner-port annular flameless ceramic burner (MAFCB) of the shaftless stove for blast furnaces was designed.The characteristics of pressure drop, homogeneousness of the flows at burner ports, and distribution of the flows in the chambers and joint were studied by cold model experiments.This type of ceramic burner was successfully applied in 6# blast furnace at Liuzhou Iron & Steel Co.Ltd.(LISC) and this practice proved that it could be used in the hot blast stove and other stoves with a higher effi-ciency and a higher steadiness of hot blast temperature at 1200℃.With the combustion of blast furnace gas alone, the thermal effi- ciency was up to 78.95%, saving energy remarkably.

  1. An integrated environmental perfusion chamber and heating system for long-term, high resolution imaging of living cells.

    Science.gov (United States)

    Hing, W A; Poole, C A; Jensen, C G; Watson, M

    2000-08-01

    This communication presents the design and application of an integrated environmental perfusion chamber and stage heating blanket suitable for time-lapse video microscopy of living cells. The system consists of two independently regulated components: a perfusion chamber suitable for the maintenance of cell viability and the variable delivery of environmental factors, and a separate heating blanket to control the temperature of the microscope stage and limit thermal conduction from the perfusion chamber. Two contrasting experiments are presented to demonstrate the versatility of the system. One long-term sequence illustrates the behaviour of cells exposed to ceramic fibres. The other shows the shrinking response of cultured articular cartilage chondrons under dynamic hyper-osmotic conditions designed to simulate joint loading. The chamber is simple in design, economical to produce and permits long-term examination of dynamic cellular behaviour while satisfying the fundamental requirements for the maintenance of environmental factors that influence cell viability.

  2. Method of fabricating a rocket engine combustion chamber

    Science.gov (United States)

    Holmes, Richard R. (Inventor); Mckechnie, Timothy N. (Inventor); Power, Christopher A. (Inventor); Daniel, Ronald L., Jr. (Inventor); Saxelby, Robert M. (Inventor)

    1993-01-01

    A process for making a combustion chamber for a rocket engine wherein a copper alloy in particle form is injected into a stream of heated carrier gas in plasma form which is then projected onto the inner surface of a hollow metal jacket having the configuration of a rocket engine combustion chamber is described. The particles are in the plasma stream for a sufficient length of time to heat the particles to a temperature such that the particles will flatten and adhere to previously deposited particles but will not spatter or vaporize. After a layer is formed, cooling channels are cut in the layer, then the channels are filled with a temporary filler and another layer of particles is deposited.

  3. Effect of test method on flexural strength of recent dental ceramics.

    Science.gov (United States)

    Jin, Jingyue; Takahashi, Hidekazu; Iwasaki, Naohiko

    2004-12-01

    The purpose of the present study was to evaluate the relationships among three flexural strengths of recent dental ceramics using 3-point and 4-point bending tests and biaxial flexural test. Three brands of porcelain for veneering (d.SIGN, Supper porcelain AAA, Vintage Hallo), two injectable ceramics (Empress 2, OPC 3G), and one castable ceramic (Crys-Cera) were used. Twenty bar-shaped and 10 disc-shaped specimens of each ceramic type were prepared according to manufacturers' instructions, polished, and subjected to 3-point and 4-point bending tests and biaxial flexural test, respectively. Three flexural strengths for each ceramics were compared using one-way analysis of variance and Tukey comparison, and also investigated by Weibull analysis. The biaxial flexural strength and 3-point bending strength of all ceramics, except OPC 3G and Crys-Cera, were significantly greater than the corresponding 4-point bending strength. As for OPC 3G and Crys-Cera, their biaxial flexural strengths were significantly greater than their 3-point bending strengths, which is contrary to the other ceramics. The Weibull moduli ranged from 6.6 to 20.8. The Weibull moduli of examined ceramics, except Crys-cera, were statistically insignificant regardless of test methods.

  4. 21 CFR 868.5470 - Hyperbaric chamber.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hyperbaric chamber. 868.5470 Section 868.5470 Food... DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5470 Hyperbaric chamber. (a) Identification. A hyperbaric chamber is a device that is intended to increase the environmental oxygen pressure to promote...

  5. Growing and analyzing biofilms in flow chambers

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim; Sternberg, Claus

    2011-01-01

    This unit describes the setup of flow chamber systems for the study of microbial biofilms, and methods for the analysis of structural biofilm formation. Use of flow chambers allows direct microscopic investigation of biofilm formation. The biofilms in flow chambers develop under hydrodynamic cond...

  6. Growing and Analyzing Biofilms in Flow Chambers

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim; Sternberg, Claus

    2011-01-01

    This unit describes the setup of flow chamber systems for the study of microbial biofilms, and methods for the analysis of structural biofilm formation. Use of flow chambers allows direct microscopic investigation of biofilm formation. The biofilms in flow chambers develop under hydrodynamic cond...

  7. Wire chamber degradation at the Argonne ZGS

    Energy Technology Data Exchange (ETDEWEB)

    Haberichter, W.; Spinka, H.

    1986-01-01

    Experience with multiwire proportional chambers at high rates at the Argonne Zero Gradient Synchrotron is described. A buildup of silicon on the sense wires was observed where the beam passed through the chamber. Analysis of the chamber gas indicated that the density of silicon was probably less than 10 ppM.

  8. LEP vacuum chamber cross-section

    CERN Multimedia

    1987-01-01

    This diagram shows the layout of the vacuum chambers used at LEP, which was in operation at CERN between 1989 and 2000. Vacuum chambers are necessary in accelerators to prevent unwanted interactions that can destabilise the beam. The pump on the right sucks air out of the chamber allowing the beam to progress with minimal interactions.

  9. Simple Cloud Chambers Using Gel Ice Packs

    Science.gov (United States)

    Kamata, Masahiro; Kubota, Miki

    2012-01-01

    Although cloud chambers are highly regarded as teaching aids for radiation education, school teachers have difficulty in using cloud chambers because they have to prepare dry ice or liquid nitrogen before the experiment. We developed a very simple and inexpensive cloud chamber that uses the contents of gel ice packs which can substitute for dry…

  10. Vacuum chamber at intersection I-6

    CERN Multimedia

    1971-01-01

    The vacuum chamber at intersection region I-6, one of these where experiments in colliding-beam physics will be taking place. The "wheels" prevent the thin wall (1.5 mm) of the chamber from collapsing. The chamber is equipped with heating tapes and its wrapped in thermal insulation. Residual gas pressure at this and other similar regions is around 10_11.

  11. Sol-gel derived ceramics

    OpenAIRE

    1990-01-01

    The synthesis of ceramic raw materials has become an important factor in ceramic technologies. The increasing demands to the performance of ceramic compounds has caused increased activities for the preparation of tailor-made raw materials. Amongst a variety of new syntheses like flame pyrolysis, reactive spray drying, plasma or laser assisted techniques, the sol-gel process plays an important and increasing role. The process describes the building up of an inorganic (in general an oxide) netw...

  12. Tailored Ceramics for Laser Applications

    Energy Technology Data Exchange (ETDEWEB)

    Hollingsworth, Joel [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2007-12-10

    Transparent ceramics match or exceed the performance of single-crystal materials in laser applications, with a more-robust fabrication process. Controlling the distribution of optical dopants in transparent ceramics would allow qualitative improvements in amplifier slab design by allowing gain and loss to be varied within the material. My work aims to achieve a controlled pattern or gradient of dopant prior to sintering, in order to produce tailored ceramics.

  13. Flash sintering of ceramic materials

    OpenAIRE

    Dancer, C. E. J.

    2016-01-01

    During flash sintering, ceramic materials can sinter to high density in a matter of seconds while subjected to electric field and elevated temperature. This process, which occurs at lower furnace temperatures and in shorter times than both conventional ceramic sintering and field-assisted methods such as spark plasma sintering, has the potential to radically reduce the power consumption required for the densification of ceramic materials. This paper reviews the experimental work on flash sint...

  14. Ceramics for High Power Lasers

    Science.gov (United States)

    2013-07-01

    ICP-MS) on 25 elements ranging from transition metals, rare earths , alkali, alkaline earths and silicon on a set of selected YAG ceramics and...our knowledge of the origin of optical losses in ceramic laser host materials while initiating a program of research on 2-micron, thulium- doped fiber...During Year 1 of this program, we produced and characterized laser grade Nd:YAG and low optical loss Gd3+ doped YAG and Tm:YAG ceramics . Laser

  15. Longevity of silicate ceramic restorations.

    Science.gov (United States)

    Beier, Ulrike Stephanie; Dumfahrt, Herbert

    2014-09-01

    The demand for esthetic restorations has resulted in an increased use of dental ceramics as a biocompatible and functionally sufficient alternative to conventional restorative materials. Silicate ceramic restorations are widely used for veneers, inlays, onlays, and crowns in dentistry. Long-term data are of crucial importance to optimize clinical practice. The purpose of the present article is to summarize data of the Innsbruck ceramic evaluation up to 261 months with the focus on longevity and failure characteristics.

  16. Preparation and characteristics of porous ceramics

    Institute of Scientific and Technical Information of China (English)

    Dongmei SHAO; Peiping ZHANG; Liyan MA; Juanjuan LIU

    2007-01-01

    Pyrophyllite is always used for making porous ceramics. In order to design the preparation technics of porous ceramics with pyrophyllite reasonably we must know the classifications, characteristics, properties and applications of porous ceramics. The classification and characteristics of porous ceramics are reviewed in this article; and several common preparations with their advantages and disadvantages are also introduced. The authors discussed the problems existing in researching and developing process for porous ceramics, and forecasted the development prospect of porous ceramics.

  17. Ceramic Composite Thin Films

    Science.gov (United States)

    Ruoff, Rodney S. (Inventor); Stankovich, Sasha (Inventor); Dikin, Dmitriy A. (Inventor); Nguyen, SonBinh T. (Inventor)

    2013-01-01

    A ceramic composite thin film or layer includes individual graphene oxide and/or electrically conductive graphene sheets dispersed in a ceramic (e.g. silica) matrix. The thin film or layer can be electrically conductive film or layer depending the amount of graphene sheets present. The composite films or layers are transparent, chemically inert and compatible with both glass and hydrophilic SiOx/silicon substrates. The composite film or layer can be produced by making a suspension of graphene oxide sheet fragments, introducing a silica-precursor or silica to the suspension to form a sol, depositing the sol on a substrate as thin film or layer, at least partially reducing the graphene oxide sheets to conductive graphene sheets, and thermally consolidating the thin film or layer to form a silica matrix in which the graphene oxide and/or graphene sheets are dispersed.

  18. Insulating Structural Ceramics Program, Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Mark J.; Tandon, Raj; Ott, Eric; Hind, Abi Akar; Long, Mike; Jensen, Robert; Wheat, Leonard; Cusac, Dave; Lin, H. T.; Wereszczak, Andrew A.; Ferber, Mattison K.; Lee, Sun Kun; Yoon, Hyung K.; Moreti, James; Park, Paul; Rockwood, Jill; Boyer, Carrie; Ragle, Christie; Balmer-Millar, Marilou; Aardahl, Chris; Habeger, Craig; Rappe, Ken; Tran, Diana; Koshkarian, Kent; Readey, Michael

    2005-11-22

    New materials and corresponding manufacturing processes are likely candidates for diesel engine components as society and customers demand lower emission engines without sacrificing power and fuel efficiency. Strategies for improving thermal efficiency directly compete with methodologies for reducing emissions, and so the technical challenge becomes an optimization of controlling parameters to achieve both goals. Approaches being considered to increase overall thermal efficiency are to insulate certain diesel engine components in the combustion chamber, thereby increasing the brake mean effective pressure ratings (BMEP). Achieving higher BMEP rating by insulating the combustion chamber, in turn, requires advances in material technologies for engine components such as pistons, port liners, valves, and cylinder heads. A series of characterization tests were performed to establish the material properties of ceramic powder. Mechanical chacterizations were also obtained from the selected materials as a function of temperature utilizing ASTM standards: fast fracture strength, fatique resistance, corrosion resistance, thermal shock, and fracture toughness. All ceramic materials examined showed excellent wear properties and resistance to the corrosive diesel engine environments. The study concluded that the ceramics examined did not meet all of the cylinder head insert structural design requirements. Therefore we do not recommend at this time their use for this application. The potential for increased stresses and temperatures in the hot section of the diesel engine combined with the highly corrosive combustion products and residues has driven the need for expanded materials capability for hot section engine components. Corrosion and strength requirements necessitate the examination of more advanced high temperture alloys. Alloy developments and the understanding of processing, structure, and properties of supperalloy materials have been driven, in large part, by the gas

  19. Rheology of Superplastic Ceramics

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Constitutive equation of rheglogy describing a phenomenological level of superplastic deformation as functional correlation between tensor components of stress and strain rate has been analyzed for the case of superplastic ceramic flow. Rheological properties of material are taken into account by means of scalar rheological coefficients of shear and volume viscosity, which are functions of temperature, effective stress (or strain rate) and density of material.

  20. Processing Nanostructured Structural Ceramics

    Science.gov (United States)

    2006-08-01

    aspects of the processing of nanostructured ceramics, viz. • • • The production of a flowable and compactable dry nanopowder suitable for use in... composition due to the different synthesis routes used. Therefore, ‘industry-standard’ dispersants can cause flocculation rather than dispersion...stabilised zirconia (3-YSZ) were no higher than for conventional, micron-sized material of the same composition . However, detailed crystallographic

  1. Dental ceramics: a current review.

    Science.gov (United States)

    Lawson, Nathaniel C; Burgess, John O

    2014-03-01

    Ceramics are used for many dental applications and are characterized in various ways, including by their hardness, brittleness, thermal and electrical insulation, and biocompatibility. The ceramics most commonly used in dentistry are oxides, particularly silicon dioxide (SiO2), or silica; aluminum oxide (Al2O3), or alumina; and zirconium dioxide (ZrO2), or zirconia. This article reviews the microstructure of current dental ceramic materials and how it relates to their mechanical properties, clinical techniques, and optical properties. Typical ceramics currently in use are described, and their clinically relevant properties such as strength, fracture, polishability, and wear are compared. Cementation methods are also discussed.

  2. Ceramic stationary gas turbine

    Energy Technology Data Exchange (ETDEWEB)

    Roode, M. van [Solar Turbines Inc., San Diego, CA (United States)

    1995-10-01

    The performance of current industrial gas turbines is limited by the temperature and strength capabilities of the metallic structural materials in the engine hot section. Because of their superior high-temperature strength and durability, ceramics can be used as structural materials for hot section components (blades, nozzles, combustor liners) in innovative designs at increased turbine firing temperatures. The benefits include the ability to increase the turbine inlet temperature (TIT) to about 1200{degrees}C ({approx}2200{degrees}F) or more with uncooled ceramics. It has been projected that fully optimized stationary gas turbines would have a {approx}20 percent gain in thermal efficiency and {approx}40 percent gain in output power in simple cycle compared to all metal-engines with air-cooled components. Annual fuel savings in cogeneration in the U.S. would be on the order of 0.2 Quad by 2010. Emissions reductions to under 10 ppmv NO{sub x} are also forecast. This paper describes the progress on a three-phase, 6-year program sponsored by the U.S. Department of Energy, Office of Industrial Technologies, to achieve significant performance improvements and emissions reductions in stationary gas turbines by replacing metallic hot section components with ceramic parts. Progress is being reported for the period September 1, 1994, through September 30, 1995.

  3. Ceramic stationary gas turbine

    Energy Technology Data Exchange (ETDEWEB)

    Roode, M. van

    1995-12-31

    The performance of current industrial gas turbines is limited by the temperature and strength capabilities of the metallic structural materials in the engine hot section. Because of their superior high-temperature strength and durability, ceramics can be used as structural materials for hot section components (blades, nozzles, combustor liners) in innovative designs at increased turbine firing temperatures. The benefits include the ability to increase the turbine inlet temperature (TIT) to about 1200{degrees}C ({approx}2200{degrees}F) or more with uncooled ceramics. It has been projected that fully optimized stationary gas turbines would have a {approx}20 percent gain in thermal efficiency and {approx}40 percent gain in output power in simple cycle compared to all metal-engines with air-cooled components. Annual fuel savings in cogeneration in the U.S. would be on the order of 0.2 Quad by 2010. Emissions reductions to under 10 ppmv NO{sub x} are also forecast. This paper describes the progress on a three-phase, 6-year program sponsored by the U.S. Department of Energy, Office of Industrial Technologies, to achieve significant performance improvements and emissions reductions in stationary gas turbines by replacing metallic hot section components with ceramic parts. Progress is being reported for the period September 1, 1994, through September 30, 1995.

  4. Effects of inhaled ceramic fibres on macrophage function of rat lungs.

    OpenAIRE

    Morimoto, Y.; Yamato, H; Kido, M; Tanaka, I; Higashi, T; Fujino, A; Yokosaki, Y

    1994-01-01

    To evaluate the biological effect of ceramic fibres on the clearance function of alveolar macrophages (AMs) morphological changes and phagocytic activity of AMs were assessed. Rats were exposed to respirable ceramic fibres with a mass median aerodynamic diameter of 4.4 microns and a concentration of 20.1 mg/m3 in an exposure chamber. They were killed after one week (group A) and two weeks (group B) of exposure, and four weeks (group C) and 12 weeks (group D) after exposure for two weeks. The ...

  5. Loss of ions in cavity ionization chambers

    Energy Technology Data Exchange (ETDEWEB)

    Takata, N. [Ionizing Radiation Section, NMIJ/AIST, Tsukuba 305-8568 (Japan)]. E-mail: n.takata@aist.go.jp; Tran, N.T. [Institute for Nuclear Science and Technique, VAEC, Hanoi (Viet Nam); Kim, E. [Radiation Safety Section, NIRS, Inageku, Chiba-city 263-8555 (Japan); Marsoem, P. [P3KRBiN-BATAN, JL Cinere-Pasar Jum' at, Jakarta 12070 (Indonesia); Kurosawa, T. [Ionizing Radiation Section, NMIJ/AIST, Tsukuba 305-8568 (Japan); Koyama, Y. [Ionizing Radiation Section, NMIJ/AIST, Tsukuba 305-8568 (Japan)

    2005-12-01

    Ion losses due to initial recombination, volume recombination, and back diffusion were each determined by measurements and calculations for different size cylindrical ionization chambers and spherical ionization chambers. By measuring signal currents from these ionization chambers irradiated with {sup 60}Co gamma rays, two groups of ion losses were obtained. (Group 1) Ion loss due to initial recombination and diffusion, which changes proportionally to the inverse of the voltage applied to the ionization chambers; (and group 2) ion loss due to volume recombination, which changes proportionally to the inverse of the square of the applied voltage. The diffusion loss was obtained separately by computing electric field distributions in the ionization chambers. It was found that diffusion loss is larger than initial recombination loss for the cylindrical ionization chambers and vise versa for the spherical ionization chambers.

  6. Pupillary block glaucoma following implantation of a posterior chamber pseudophakos in the anterior chamber.

    Directory of Open Access Journals (Sweden)

    Mandal Anil

    2002-01-01

    Full Text Available Pupillary block glaucoma is a common complication of cataract surgery, especially following anterior chamber intraocular lens implantation. We report a case of pupillary block glaucoma with a posterior chamber IOL that was implanted in the anterior chamber following a complicated extracapsular cataract extraction. The case was successfully managed by explantation of the posterior chamber lens, anterior vitrectomy, peripheral iridectomy and secondary anterior chamber intraocular lens implantation. The intraocular pressure was controlled with a single topical antiglaucoma medication.

  7. Lower energy costs in the ceramics industry - via ceramic fibers

    Energy Technology Data Exchange (ETDEWEB)

    Zander, H.P.

    1983-04-01

    Ceramic fibres, due to their high thermal and chemical resistance, receive increasing attention as insulating material for industrial purposes. After a short characterisation, examples of furnace wall lining are given, and a tunnel-kiln car for baking of sanitation ceramics is investigated with a view to possibilities of supplementary insulation.

  8. Basic Aerodynamics of Combustion Chambers,

    Science.gov (United States)

    1981-05-20

    8217, tie imnrulse foree eyuilibr-um c’ the bomd’~ leye - is 173 pv-:irJ p~76vJbK 2sO) IL !-. = Zn pT -- a , bV T. z -,,r y.re C era 3oia * ~~I" onc art-=e...heat by combustion all have very large influences on the capabilities of a combustion chamber. A yellow- colored flame represents diffusion combustion in...the wakes of fuel droplets. Blue- colored flames represent gaseous combustion of evaporated vapors which have already left the fuel droplets. The

  9. Ceramic-on-ceramic total hip arthroplasty: update.

    Science.gov (United States)

    Capello, William N; D'Antonio, James A; Feinberg, Judy R; Manley, Michael T; Naughton, Marybeth

    2008-10-01

    This prospective, randomized, multicenter study of alumina ceramic-on-alumina ceramic bearing couples includes 452 patients (475 hips). Their average age was 53 years with approximately two thirds men and 82% with osteoarthritis. At an average 8-year follow-up, clinical results were excellent and cortical erosions significantly less than in the conventional polyethylene-on-metal bearing group. Nine hips have undergone revision of one or both components for any reason. Of the 380 ceramic liners, 2 (0.5%) have fractured requiring reoperation, and 3 (0.8%) ceramic patients reported a transient squeaking sound, one of which had a head and liner change due to groin pain secondary to psoas tendinitis at 5 years. With no revisions for aseptic loosening and minimal cortical erosions, alumina-ceramic bearing couples are performing in a manner superior to the polyethylene-on-metal bearing in this young, active patient population.

  10. Length scales in cryogenic injection at supercritical pressure

    Energy Technology Data Exchange (ETDEWEB)

    Branam, R.; Mayer, W. [German Aerospace Center, DLR Lampoldshausen, 74239 Hardthausen (Germany)

    2002-09-01

    Length scales provide some understanding of the injection of cryogenic propellants in rocket chambers on mixing efficiency, which translates to burning efficiency and performance. This project uses supercritical cryogenic nitrogen to look at high-density core flows such as those of coaxial injectors used in rocket engines. The investigation considers test conditions from 4.0 to 6.0 MPa chamber pressure at two injection velocities and temperatures. Experimental data taken by using shadowgraph images provides a means of characterizing turbulent flow structures using a two-point correlation method to determine length scales and structure shapes. The experimental results are compared to computational models. (orig.)

  11. Transition duct with late injection in turbine system

    Energy Technology Data Exchange (ETDEWEB)

    LeBegue, Jeffrey Scott; Pentecost, Ronnie Ray; Flanagan, James Scott; Kim, Won -Wook; McMahan, Kevin Weston

    2015-09-15

    A system for supplying an injection fluid to a combustor is disclosed. The system includes a transition duct comprising an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis. The outlet of the transition duct is offset from the inlet along the longitudinal axis and the tangential axis. The passage defines a combustion chamber. The system further includes a tube providing fluid communication for the injection fluid to flow through the transition duct and into the combustion chamber.

  12. Multi-Dimensional Modeling of the Effects of Air Jet and Split Injection on Combustion and Emission of DirectInjection Diesel Engine

    Directory of Open Access Journals (Sweden)

    Mehdi Mansury

    2016-01-01

    Full Text Available One of the most important problems in reducing the emissions of diesel engines is to exchange between the oxides of nitrogen and soot emissions. Fuel multiple injection and air injection into combustion chamber are among the most powerful tools to concurrent reduction of these two emissions. In this research, the effect of multiple injection and air injection on combustion and emission parameters has been studied by AVL fire computational fluid dynamic software. Six states of base and modified combustion chamber have been studied in two different injection patterns including 90 (25 10 and 75 (25 25 mods. Results show that concurrent applying of both multiple injection and air injection methods has resulted in simultaneous reduction of oxide nitrogen and soot pollutants and a negligible loss is seen in the operational parameters of engine. Compression between six studied cases show that the 90 (25 10 mode of injection with modified combustion chamber is the optimum mode by decreasing of soot and oxides of nitrogen emissions about 29% and 20% respectively and 6% indicated power loss in compression to the base combustion chamber and single injection mode. The obtained results from the computational fluid dynamic code have been compared with the existing results in the technical literature and show acceptable behavior.

  13. Physicist makes muon chamber sing

    CERN Document Server

    2007-01-01

    This Monitored Drift Tube detector, consisting of argon-CO2-filled aluminium tubes with a wire down the centre of each, will track muons in ATLAS; Tiecke used a single tube from one of these detectors to create the pipes in his organ. Particle physicists can make good musicians; but did you know particle detectors can make good music? That's what NIKHEF physicist Henk Tiecke learned when he used pipes cut from the ATLAS Monitored Drift Tube detector (MDT) to build his own working Dutch-style barrel organ in the autumn of 2005. 'I like to work with my hands,' said Tiecke, who worked as a senior physicist at NIKHEF, Amsterdam, on ZEUS until his retirement last summer. Tiecke had already constructed his barrel organ when he visited some colleagues in the ATLAS muon chambers production area at Nikhef in 2005. He noticed that the aluminium tubes they were using to build the chambers were about three centimetres in diameter-just the right size for a pipe in a barrel organ. 'The sound is not as nice as from wooden...

  14. Limits to Drift Chamber Resolution

    CERN Document Server

    Riegler, Werner

    1998-01-01

    ATLAS (A Large Toroidal LHC Apparatus) will be a general-purpose experiment at the Large Hadron Collider that will be operational at CERN in the year 2004. The ATLAS muon spectrometer aims for a momentum resolution of 10% for a transverse momentum of pT=1TeV. The precision tracking devices in the muon system will be high pressure drift tubes (MDTs) with a single wire resolution of 1100 chambers covering an area of ≈ 2500m2. The high counting rates in the spectrometer as well as the aim for excellent spatial resolution and high efficiency put severe constraints on the MDT operating parameters. This work describes a detailed study of all the resolution limiting factors in the ATLAS environment. A ’full chain’ simulation of the MDT response to photons and charged particles as well as quantitative comparisons with measurements was performed. The good agreement between simulation and measurements resulted in a profound understanding of the drift chamber processes and the individual contributions to the spat...

  15. Improved Tensile Test for Ceramics

    Science.gov (United States)

    Osiecki, R. A.

    1982-01-01

    For almost-nondestructive tensile testing of ceramics, steel rod is bonded to sample of ceramic. Assembly is then pulled apart in conventional tensile-test machine. Test destroys only shallow surface layer which can be machined away making specimen ready for other uses. Method should be useful as manufacturing inspection procedure for low-strength brittle materials.

  16. Ceramics in nuclear waste management

    Energy Technology Data Exchange (ETDEWEB)

    Chikalla, T D; Mendel, J E [eds.

    1979-05-01

    Seventy-three papers are included, arranged under the following section headings: national programs for the disposal of radioactive wastes, waste from stability and characterization, glass processing, ceramic processing, ceramic and glass processing, leaching of waste materials, properties of nuclear waste forms, and immobilization of special radioactive wastes. Separate abstracts were prepared for all the papers. (DLC)

  17. Improvements to parallel plate flow chambers to reduce reagent and cellular requirements

    Directory of Open Access Journals (Sweden)

    Larson Richard S

    2001-09-01

    Full Text Available Abstract Background The parallel plate flow chamber has become a mainstay for examination of leukocytes under physiologic flow conditions. Several design modifications have occurred over the years, yet a comparison of these different designs has not been performed. In addition, the reagent requirements of many designs prohibit the study of rare leukocyte populations and require large amounts of reagents. Results In this study, we evaluate modifications to a newer parallel plate flow chamber design in comparison to the original parallel plate flow chamber described by Lawrence et al. We show that modifications in the chamber size, internal tubing diameters, injection valves, and a recirculation design may dramatically reduce the cellular and reagent requirements without altering measurements. Conclusions These modifications are simple and easily implemented so that study of rare leukocyte subsets using scarce or expensive reagents can occur.

  18. Method of forming a ceramic matrix composite and a ceramic matrix component

    Energy Technology Data Exchange (ETDEWEB)

    de Diego, Peter; Zhang, James

    2017-05-30

    A method of forming a ceramic matrix composite component includes providing a formed ceramic member having a cavity, filling at least a portion of the cavity with a ceramic foam. The ceramic foam is deposited on a barrier layer covering at least one internal passage of the cavity. The method includes processing the formed ceramic member and ceramic foam to obtain a ceramic matrix composite component. Also provided is a method of forming a ceramic matrix composite blade and a ceramic matrix composite component.

  19. Preparation of Bauxite Ceramic Microsphere

    Institute of Scientific and Technical Information of China (English)

    CHENG Xiaosu; LIU Pingan; LI Xiuyan; SHUI Anze; ZENG Lingke

    2007-01-01

    Ceramic microspheres were prepared by using Chinese bauxite as raw materials through the centrifugal spray drying method. The control technology of microsphere size, degree of sphericity was researched. The ceramic microspheres were sintered by a double sintering process. The microstructure and composition of ceramic microsphere were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray energy spectroscopy. The results show that the degree of sphericity of the ceramic microsphere was good and the particle size was 10-100 μm. The XRD analysis reveals that the main crystalline phase of the ceramic microsphere was α- Al2O3 and mullite (3Al2O3·2SiO2). The product can be used as reinforced material for composite material, especially for antiskid and hard wearing aluminum alloy coating.

  20. Low thermal expansion glass ceramics

    CERN Document Server

    1995-01-01

    This book is one of a series reporting on international research and development activities conducted by the Schott group of companies With the series, Schott aims to provide an overview of its activities for scientists, engineers, and managers from all branches of industry worldwide where glasses and glass ceramics are of interest Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated This volume describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization Thus glass ceramics with thermal c...

  1. Ceramic membrane development in NGK

    Science.gov (United States)

    Araki, Kiyoshi; Sakai, Hitoshi

    2011-05-01

    NGK Insulators, Ltd. was established in 1919 to manufacture the electric porcelain insulators for power transmission lines. Since then, our business has grown as one of the world-leading ceramics manufacturing companies and currently supply with the various environmentally-benign ceramic products to worldwide. In this paper, ceramic membrane development in NGK is described in detail. We have been selling ceramic microfiltration (MF) membranes and ultra-filtration (UF) membranes for many years to be used for solid/liquid separation in various fields such as pharmaceutical, chemical, food and semiconductor industries. In Corporate R&D, new ceramic membranes with sub-nanometer sized pores, which are fabricated on top of the membrane filters as support, are under development for gas and liquid/liquid separation processes.

  2. Ceramic membrane development in NGK

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Kiyoshi; Sakai, Hitoshi, E-mail: kinsakai@ngk.co.jp [Corporate R and D, NGK Insulators, Ltd., Nagoya 467-8530 (Japan)

    2011-05-15

    NGK Insulators, Ltd. was established in 1919 to manufacture the electric porcelain insulators for power transmission lines. Since then, our business has grown as one of the world-leading ceramics manufacturing companies and currently supply with the various environmentally-benign ceramic products to worldwide. In this paper, ceramic membrane development in NGK is described in detail. We have been selling ceramic microfiltration (MF) membranes and ultra-filtration (UF) membranes for many years to be used for solid/liquid separation in various fields such as pharmaceutical, chemical, food and semiconductor industries. In Corporate R and D, new ceramic membranes with sub-nanometer sized pores, which are fabricated on top of the membrane filters as support, are under development for gas and liquid/liquid separation processes.

  3. Transferring calibration coefficients from ionisation chambers used for diagnostic radiology to transmission chambers.

    Science.gov (United States)

    Yoshizumi, Maíra T; Caldas, Linda V E

    2012-07-01

    In this work, the response of a double volume transmission ionisation chamber, developed at the Instituto de Pesquisas Energéticas e Nucleares, was compared to that of a commercial transmission chamber. Both ionisation chambers were tested in different X-ray beam qualities using secondary standard ionisation chambers as reference dosimeters. These standard ionisation chambers were a parallel-plate and a cylindrical ionisation chambers, used for diagnostic radiology and mammography beam qualities, respectively. The response of both transmission chambers was compared to that of the secondary standard chambers to obtain coefficients of equivalence. These coefficients allow the transmission chambers to be used as reference equipment. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Penicillin G Procaine Injection

    Science.gov (United States)

    Penicillin G procaine injection is used to treat certain infections caused by bacteria. Penicillin G procaine injection should not be used to treat ... in the treatment of certain serious infections. Penicillin G procaine injection is in a class of medications ...

  5. In-situ combustion with solvent injection

    Energy Technology Data Exchange (ETDEWEB)

    D' Silva, J.; Kakade, G. [Society of Petroleum Engineers, Kuala Lumpur (Malaysia)]|[Maharashtra Inst. of Technology, Pune (India)

    2008-10-15

    The effects of combining in situ combustion and heavy hydrocarbon naphtha vapor injection techniques in a heavy oil reservoir were investigated. Oil production rates and steam injection efficiencies were considered. The technique was also combined with toe-to-heel air injection (THAI) processes. The study showed that the modified THAI process achieved high rates of recovery for both primary production and as a follow-up technique in partially depleted reservoirs after cyclic steam and cold production. Oil produced using the modified THAI technique was also partially upgraded by the process. Results of the vapour chamber pressure calculations showed that the volume of oil produced by naphtha assisted gravity drainage was between 1 to 3 times higher than amounts of oil produced by SAGD processes during the same amount of time. The naphtha injection process produced more oil than the steam only process. However, high amounts of naphtha were needed to produce oil. Injection and production rates during the naphtha injection process were higher. Naphtha vapor was injected near the heel of a horizontal producer well. The vapor acted as a thermal and diluent mechanism in order to reduce the viscosity of the heavy oil . 9 refs., 4 tabs., 6 figs.

  6. The LHC injection kicker magnet

    CERN Document Server

    Ducimetière, Laurent; Barnes, M J; Wait, G D

    2003-01-01

    Proton beams will be injected into LHC at 450 GeV by two kicker magnet systems, producing magnetic field pulses of approximately 900 ns rise time and up to 7.86 s flat top duration. One of the stringent design requirements of these systems is a flat top ripple of less than ± 0.5%. Both injection systems are composed of 4 travelling wave kicker magnets of 2.7 m length each, powered by pulse forming networks (PFN's). To achieve the required kick strength of 1.2 Tm, a low characteristic impedance has been chosen and ceramic plate capacitors are used to obtain 5 Omega. Conductive stripes in the aperture of the magnets limit the beam impedance and screen the ferrite. The electrical circuit has been designed with the help of PSpice computer modelling. A full size magnet prototype has been built and tested up to 60 kV with the magnet under ultra high vacuum (UHV). The pulse shape has been precision measured at a voltage of 15 kV. After reviewing the performance requirements the paper presents the magnet...

  7. Ion distributions in plane and cylindrical chambers.

    Science.gov (United States)

    Rosen, R; George, E P

    1975-11-01

    The ion chamber equations of Thomson include both ion recombination and space-charge terms. Neglecting the space-charge term, an exact solution is obtained for the ion densities across a plane ionization chamber. The method is extended to the cylindrical chamber, and examples are given of the expected ion distributions in both geometries. Current-voltage relationships are derived for both chambers and compared with those of other workers. If the space-charge term is retained, the ion chamber equations for both geometries are not soluble in closed form. The cylindrical chamber is considered and a computer solution is obtained for the ion distributions and current. Comparison with the nonspace-charge solution shows that while there is only a small difference in the current-voltage relationship, a significant difference can occur in the ion concentrations.

  8. A mathematical model of aerosol holding chambers

    DEFF Research Database (Denmark)

    Zak, M; Madsen, J; Berg, E

    1999-01-01

    A mathematical model of aerosol delivery from holding chambers (spacers) was developed incorporating tidal volume (VT), chamber volume (Vch), apparatus dead space (VD), effect of valve insufficiency and other leaks, loss of aerosol by immediate impact on the chamber wall, and fallout of aerosol...... in the chamber with time. Four different spacers were connected via filters to a mechanical lung model, and aerosol delivery during "breathing" was determined from drug recovery from the filters. The formula correctly predicted the delivery of budesonide aerosol from the AeroChamber (Trudell Medical, London......, Ontario, Canada), NebuChamber (Astra, Södirtälje, Sweden) and Nebuhaler (Astra) adapted for babies. The dose of fluticasone proportionate delivered by the Babyhaler (Glaxco Wellcome, Oxbridge, Middlesex, UK) was 80% of that predicted, probably because of incomplete priming of this spacer. Of the above...

  9. Tests of anechoic chamber for aeroacoustics investigations

    Science.gov (United States)

    Palchikovskiy, V. V.; Bersenev, Yu. V.; Makashov, S. Yu.; Belyaev, I. V.; Korin, I. A.; Sorokin, E. V.; Khramtsov, I. V.; Kustov, O. Yu.

    2016-10-01

    The paper presents the results of qualification tests in the new anechoic chamber of Perm National Research Polytechnic University (PNRPU) built in 2014-2015 and evaluation of the chamber quality in aeroacoustic experiments. It describes design features of the chamber and its sound-absorption lining. The qualification tests were carried out with tonal and broadband noise sources in the frequency range 100 Hz - 20 kHz for two different cases of the source arrangement. In every case, measurements were performed in three directions by traverse microphones. Qualification tests have determined that in the chamber there is a free acoustic field within radius of 2 m for tonal noise and 3 m for broadband noise. There was also evaluated acoustic quality of the chamber by measurements of the jet noise and vortex ring noise. The results of the experiments demonstrate that PNRPU anechoic chamber allows the aeroacoustic measurements to be performed to obtain quantitative results.

  10. High-temperature corrosion resistance of ceramics and ceramic coatings

    Energy Technology Data Exchange (ETDEWEB)

    Tortorelli, P.F.

    1996-06-01

    Ceramics and ceramic composites offer the potential to operate fossil energy systems at the higher temperatures necessary for improved energy efficiency and better environmental control. However, because many fossil fuel-derived processes contain sulfur, chlorine, and carbon, as well as oxygen, degradation from high-temperature corrosion and environmental effects arising from reactions of solids with gases and condensable products is a common life-determining factor in operating systems. Ceramic-based products are not immune to such degradation; adequate corrosion resistance must be assured to exploit the technical and economic potential of such materials. This is normally accomplished by using stable, sound oxides that exist in their bulk form, that naturally grow as surface layers upon exposure to an oxidizing environment, or that are deposited as a coating on a susceptible material. It is therefore important to examine the critical issues with respect to more environmental stability of ceramics that have the potential to be corrosion resistant in particular fossil environments. Key aspects include not only chemical compatibility, but the influence of the environment on the mechanical behavior of the ceramic materials. In addition, for coatings, the mechanical reliability of the ceramic is a key issue in that an otherwise corrosion-resistant surface layer must remain sound and adherent in order to provide protection to the underlying substrate. The purpose of this work is to support the development of advanced ceramics and ceramic composites for applications in fossil environments by examining critical issues related to high-temperature corrosion resistance. More specifically, the overall objective of this task is to examine the chemical compatibility and reliability of potentially corrosion-resistant ceramics being developed as protective overcoats and/or structural materials as parts of other work elements funded by the AR&TD Program.

  11. Simulation of noncondensable gases in SAGD steam chambers

    Energy Technology Data Exchange (ETDEWEB)

    Gittins, Simon; Gupta, Subodh; Zaman, Maliha [Cenovus Energy (Canada)

    2011-07-01

    Cenovus Energy has been successfully using the steam assisted gravity drainage (SAGD) process at various sites. As these and other wells mature, a greater understanding of non-condensable gasses is required to help to optimize other factors such as methane co-injection and the steam ramp-down and blow-down phases. It is very important to understand fully how non-condensable gasses operate in SAGD chambers in order to lower energy intensity, costs, and the environmental impact while increasing the yield from the reserves. Cenovus Energy also plans on reducing pressure in SAGD and solvent-aided processes in future projects by applying their acquired knowledge of non-condensable gasses. The paper shows results from recent simulations that improve understanding of this subject. Simulation has shown that if there are significant flow restrictions in SAGD injection wells, that would cause the steam to flow at a higher pressure axially along the steam chamber as opposed to axially along the liner and out. This accounts for the production of solution gas.

  12. The CAST Time Projection Chamber

    CERN Document Server

    Autiero, D; Cébrian, S; Carmona, J M; Chesi, Enrico Guido; Davenport, M; Delattre, M; Di Lella, L; Formenti, F; Gomez, H; Hasinoff, M; Irastorza, I G; Lakic, B; Luzón, G; Morales, J; Musa, L; Ortiz, A; Placci, A; Rodríguez, A; Ruz, J; Villar, J A; Zioutas, K

    2007-01-01

    One of the three X-ray detectors of the CAST experiment searching for solar axions is a Time Projection Chamber (TPC) with a multi-wire proportional counter (MWPC) as a readout structure. Its design has been optimized to provide high sensitivity to the detection of the low intensity X-ray signal expected in the CAST experiment. A low hardware threshold of 0.8 keV is safely set during normal data taking periods, and the overall efficiency for the detection of photons coming from conversion of solar axions is 62 %. Shielding has been installed around the detector, lowering the background level to 4.10 x 10^-5 counts/cm^2/s/keV between 1 and 10 keV. During phase I of the CAST experiment the TPC has provided robust and stable operation, thus contributing with a competitive result to the overall CAST limit on axion-photon coupling and mass.

  13. The ARGUS microvertex drift chamber

    Science.gov (United States)

    Michel, E.; Schmidt-Parzefall, W.; Appuhn, R. D.; Buchmüller, J.; Kolanoski, H.; Kreimeier, B.; Lange, A.; Siegmund, T.; Walther, A.; Edwards, K. W.; Fernholz, R. C.; Kapitza, H.; MacFarlane, D. B.; O'Neill, M.; Parsons, J. A.; Prentice, J. D.; Seidel, S. C.; Tsipolitis, G.; Ball, S.; Babaev, A.; Danilov, M.; Tichomirov, I.

    1989-11-01

    The ARGUS collaboration is currently building a new microvertex drift chamber (μVDC) as an upgrade of their detector. The μVDC is optimized for B-meson physics at DORIS energies. Important design features are minimal multiple scattering for low-momentum particles and three-dimensional reconstruction of decay vertices with equal resolutions in r- φ and r- z. Vertex resolutions of 15-25 μm are expected. Prototypes of the μVDC have been tested with different gas mixtures at various pressures. Spatial resolutions as small as 20 μm were obtained using CO 2/propane at 4 bar and DME at 1 bar. New readout electronics have been developed for the μVDC aiming at low thresholds for the TDC measurements. Employing a novel idea for noise and cross-talk suppression, which is based on a discrimination against short pulses, very low threshold settings are possible.

  14. Drift chamber tracking with neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Lindsey, C.S.; Denby, B.; Haggerty, H.

    1992-10-01

    We discuss drift chamber tracking with a commercial log VLSI neural network chip. Voltages proportional to the drift times in a 4-layer drift chamber were presented to the Intel ETANN chip. The network was trained to provide the intercept and slope of straight tracks traversing the chamber. The outputs were recorded and later compared off line to conventional track fits. Two types of network architectures were studied. Applications of neural network tracking to high energy physics detector triggers is discussed.

  15. Bubble chamber: Omega production and decay

    CERN Multimedia

    1973-01-01

    This image is taken from one of CERN's bubble chambers and shows the decay of a positive kaon in flight. The decay products of this kaon can be seen spiraling in the magnetic field of the chamber. The invention of bubble chambers in 1952 revolutionized the field of particle physics, allowing real tracks left by particles to be seen and photographed by expanding liquid that has been heated to boiling point.

  16. Free-Flow Open-Chamber Electrophoresis

    Science.gov (United States)

    Sharnez, Rizwan; Sammons, David W.

    1994-01-01

    Free-flow open-chamber electrophoresis variant of free-flow electrophoresis performed in chamber with open ends and in which velocity of electro-osmotic flow adjusted equal to and opposite mean electrophoretic velocity of sample. Particles having electrophoretic mobilities greater than mean mobility of sample particles move toward cathode, those with mobilities less move toward anode. Technique applied to separation of components of mixtures of biologically important substances. Sensitivity enhanced by use of tapered chamber.

  17. Iron Dextran Injection

    Science.gov (United States)

    ... allergic to iron dextran injection; any other iron injections such as ferric carboxymaltose (Injectafer), ferumoxytol (Feraheme), iron sucrose (Venofer), or sodium ferric gluconate (Ferrlecit);any other ...

  18. The effect of filler on the temperature coefficient of the relative permittivity of PTFE/ceramic composites

    Science.gov (United States)

    Rajesh, S.; Murali, K. P.; Jantunen, H.; Ratheesh, R.

    2011-11-01

    High permittivity and low-loss ceramic fillers have been prepared by means of the solid state ceramic route. Ceramic-filled composites were prepared by the Sigma Mixing, Extrusion, Calendering, which was followed by the Hot pressing (SMECH) process. The microwave dielectric properties of the composites were studied using X-band waveguide cavity perturbation technique. The temperature coefficient of the relative permittivity of the composites was investigated in the 0-100 °C temperature range using a hot and cold chamber coupled with an impedance analyzer. The temperature coefficient of the relative permittivity of the composites showed strong dependence on the temperature coefficient of the relative permittivity of the filler material. In the present study, a high-permittivity polymer/ceramic composite, having τεr ∼63 ppm/K, has been realized. This composite is suitable for outdoor wireless applications.

  19. Integral Textile Ceramic Structures

    Science.gov (United States)

    Marshall, David B.; Cox, Brian N.

    2008-08-01

    A new paradigm for ceramic composite structural components enables functionality in heat exchange, transpiration, detailed shape, and thermal strain management that significantly exceeds the prior art. The paradigm is based on the use of three-dimensional fiber reinforcement that is tailored to the specific shape, stress, and thermal requirements of a structural application and therefore generally requires innovative textile methods for each realization. Key features include the attainment of thin skins (less than 1 mm) that are nevertheless structurally robust, transpiration holes formed without cutting fibers, double curvature, compliant integral attachment to other structures that avoids thermal stress buildup, and microcomposite ceramic matrices that minimize spalling and allow the formation of smooth surfaces. All these features can be combined into structures of very varied gross shape and function, using a wide range of materials such as all-oxide systems and SiC and carbon fibers in SiC matrices. Illustrations are drawn from rocket nozzles, thermal protection systems, and gas turbine engines. The new design challenges that arise for such material/structure systems are being met by specialized computational modeling that departs significantly in the representation of materials behavior from that used in conventional finite element methods.

  20. Engineering verification of the biomass production chamber

    Science.gov (United States)

    Prince, R. P.; Knott, W. M., III; Sager, J. C.; Jones, J. D.

    1992-01-01

    The requirements for life support systems, both biological and physical-chemical, for long-term human attended space missions are under serious study throughout NASA. The KSC 'breadboard' project has focused on biomass production using higher plants for atmospheric regeneration and food production in a special biomass production chamber. This chamber is designed to provide information on food crop growth rate, contaminants in the chamber that alter plant growth requirements for atmospheric regeneration, carbon dioxide consumption, oxygen production, and water utilization. The shape and size, mass, and energy requirements in relation to the overall integrity of the biomass production chamber are under constant study.

  1. The Mark II Vertex Drift Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, J.P.; Baggs, R.; Fujino, D.; Hayes, K.; Hoard, C.; Hower, N.; Hutchinson, D.; Jaros, J.A.; Koetke, D.; Kowalski, L.A.

    1989-03-01

    We have completed constructing and begun operating the Mark II Drift Chamber Vertex Detector. The chamber, based on a modified jet cell design, achieves 30 {mu}m spatial resolution and <1000 {mu}m track-pair resolution in pressurized CO{sub 2} gas mixtures. Special emphasis has been placed on controlling systematic errors including the use of novel construction techniques which permit accurate wire placement. Chamber performance has been studied with cosmic ray tracks collected with the chamber located both inside and outside the Mark II. Results on spatial resolution, average pulse shape, and some properties of CO{sub 2} mixtures are presented. 10 refs., 12 figs., 1 tab.

  2. Precision Radio Frequency Anechoic Chamber Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Performs measurements and calibration of antennas for satellites and aircraft or groundbased systems. The chamber is primarily used for optimizing antenna...

  3. Bicone vacuum chamber for ISR intersection

    CERN Document Server

    1975-01-01

    This is one of the bicone chambers made of titanium for experiment R 702. The central corrugated part had a very thin titanium wall (0.28 mm). The first of these chambers collapsed in its central part when baked at 300 C (August 1975). After an intensive effort to develop better quality and reproducible welds for this special material, the ISR workshop was able to build two new chambers of this type. One of them was installed at I 7 for R 702 in 1976 and worked perfectly. It was at that time the most "transparent" intersection vacuum chamber. See also 7609219, 7609221.

  4. High pressure ceramic heat exchanger

    Science.gov (United States)

    Harkins, Bruce D.; Ward, Michael E.

    1998-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  5. A drop-on-demand ink-jet printer for combinatorial libraries and functionally graded ceramics.

    Science.gov (United States)

    Mohebi, Mohammad Masoud; Evans, Julian R G

    2002-01-01

    A printer has been designed and built for the preparation of combinatorial libraries of ceramics and for solid freeforming of functionally graded ceramics with three-dimensionally programmable spatial variation in composition. Several ceramic suspensions (as inks) can be subjected to micromixing behind the nozzle and printed at precise positions. Both mixing and positioning are computer-controlled. The machine consists of an XY table to control the geometry, a set of electromagnetic valves that manage the mixing, a combined electromagnetic valve and sapphire nozzle that form the print head, and a computer that controls the whole system. The mixing valves can eject as little as 1 mg/s ink into the mixing chamber. The printer has been controlled, run, calibrated and tested; the composition and geometry of printed mixtures can be controlled precisely. This method for the controlled mixing of powders facilitates the advance of combinatorial methods within the materials sciences.

  6. Incipient flocculation molding: A new ceramic-forming technique

    Science.gov (United States)

    Arrasmith, Steven Reade

    Incipient Flocculation Molding (IFM) was conceived as a new near-net-shape forming technique for ceramic components. It was hypothesized that the development of a temperature-dependent deflocculant would result in a forming technique that is flexible, efficient, and capable of producing a superior microstructure with improved mechanical properties from highly reactive, submicron ceramic powders. IFM utilizes a concentrated, nonaqueous, sterically stabilized ceramic powder and/or colloidal suspension which is injected into a non-porous mold. The suspension is then flocculated by destabilizing the suspension by lowering the temperature. Flocculation is both rapid and reversible. Cooling to -20°C produces a green body with sufficient strength for removal from the mold. The solvent is removed from the green body by evaporation. The dried green body is subsequently sintered to form a dense ceramic monolith. This is the first ceramic forming method based upon the manipulation of a sterically-stabilized suspension. To demonstrate IFM, the process of grafting polyethylene glycol (PEG), with molecular weights from 600 to 8000, to alumina powders was investigated. The maximum grafted amounts were achieved by the technique of dispersing the alumina powders in molten polymer at 195°C. The ungrafted PEG was then removed by repeated centrifuging and redispersion in fresh distilled water. The rheological behavior of suspensions of the PEG-grafted powders in water, 2-propanol and 2-butanol were characterized. All of the aqueous suspensions were shear thinning. The PEG 4600-grafted alumina powder aqueous suspensions were the most fluid. Sample rods and bars were molded from 52 vol% PEG-grafted alumina suspensions in 2-butanol. The best results were obtained with a preheated aluminum mold lubricated with a fluorinated oil mold-release. The samples were dried, sintered, and their microstructure and density were compared with sintered samples dry pressed from the same alumina powder

  7. Strength and Microstructure of Ceramics.

    Science.gov (United States)

    1991-10-01

    34 microplasticity " stage in crack initiation from the flaw’ " for alumina ceramics has been carried out. Results of (from literal adaptations of the original...us to identify frontal-zone microcracking or even microplasticity . However. bridge degradation as a cause of the fatigue process. "Wear" direct...Ceramics", J. Aust. Ceram. Soc. 16 4-9. [24] A.W. Ruff and S.M. Wiederhorn (1979) "Erosion by Solid Particle Impact ", in Treatise on Materials Science and

  8. Adipose tissue extract promotes adipose tissue regeneration in an adipose tissue engineering chamber model.

    Science.gov (United States)

    Lu, Zijing; Yuan, Yi; Gao, Jianhua; Lu, Feng

    2016-05-01

    An adipose tissue engineering chamber model of spontaneous adipose tissue generation from an existing fat flap has been described. However, the chamber does not completely fill with adipose tissue in this model. Here, the effect of adipose tissue extract (ATE) on adipose tissue regeneration was investigated. In vitro, the adipogenic and angiogenic capacities of ATE were evaluated using Oil Red O and tube formation assays on adipose-derived stem cells (ASCs) and rat aortic endothelial cells (RAECs), respectively. In vivo, saline or ATE was injected into the adipose tissue engineering chamber 1 week after its implantation. At different time points post-injection, the contents were morphometrically, histologically, and immunohistochemically evaluated, and the expression of growth factors and adipogenic genes was analyzed by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time PCR. With the exception of the baseline control group, in which fat flaps were not inserted into a chamber, the total volume of fat flap tissue increased significantly in all groups, especially in the ATE group. Better morphology and structure, a thinner capsule, and more vessels were observed in the ATE group than in the control group. Expression of angiogenic growth factors and adipogenic markers were significantly higher in the ATE group. ATE therefore significantly promoted adipose tissue regeneration and reduced capsule formation in an adipose tissue engineering chamber model. These data suggest that ATE provides a more angiogenic and adipogenic microenvironment for adipose tissue formation by releasing various cytokines and growth factors that also inhibit capsule formation.

  9. Modeling of Liquid Level and Bubble Behavior in Vacuum Chamber of RH Process

    Institute of Scientific and Technical Information of China (English)

    Yi-hong LI; Yan-ping BAO; Rui WANG; Min WANG; Qing-xue HUANG; Yu-gui LI

    2016-01-01

    In the Ruhrstahl-Heraeus (RH)refining process,liquid steel flow pattern in a ladle is controlled by the fluid flow behavior in the vacuum chamber.Potassium chloride solution and NaOH solution saturated with CO 2 were respectively used as a tracer to investigate the liquid and gas flow behaviors in the vacuum chamber.Principal compo-nent and comparative analysis were made to show the factors controlling mixing and circulation flow rate.The liquid level and bubble behavior in the vacuum chamber greatly affect fluid flow in RH process.Experiments were per-formed to investigate the effects of liquid steel level,gas flow rate,bubble residence time,and gas injection mode on mixing,decarburization,and void fraction.The results indicate that the mixing process can be divided into three re-gions:the flow rate-affected zone,the concentration gradient-affected zone,and their combination.The liquid steel level in the vacuum chamber of 300 mm is a critical point in the decarburization transition.For liquid level lower than 300 mm,liquid steel circulation controls decarburization,while for liquid level higher than 300 mm,bubble behavior is the main controlling factor.During the RH process,it is recommended to use the concentrated bubble injection mode for low gas flow rates and the uniform bubble injection mode for high gas flow rates.

  10. Sipuleucel-T Injection

    Science.gov (United States)

    Sipuleucel-T injection is used to treat certain types of advanced prostate cancer. Sipuleucel-T injection is in a class of medications called ... Sipuleucel-T injection comes as a suspension (liquid) to be injected over about 60 minutes into a vein ...

  11. Raymond J. Chambers--A Personal Reflection

    Science.gov (United States)

    Gaffikin, Michael

    2012-01-01

    This paper is presented as a tribute to Raymond J. Chambers. As its title suggests, it is a personal reflection through the eyes of someone who worked closely with him over a period of 10 years during a latter part of his career, and who completed a doctoral thesis with aspects of the work of Chambers as its subject. During this time, author…

  12. Results from the MAC Vertex chamber

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, H.N.

    1987-05-01

    The design, construction, and performance characteristics of a high precision gaseous drift chamber made of thin walled proportional tubes are described. The device achieved an average spatial resolution of 45 ..mu..m in use for physics analysis with the MAC detector. The B-lifetime result obtained with this chamber is discussed.

  13. 21 CFR 866.2120 - Anaerobic chamber.

    Science.gov (United States)

    2010-04-01

    ... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Microbiology Devices § 866.2120 Anaerobic chamber. (a) Identification. An anaerobic chamber is a device intended for medical purposes to maintain an anaerobic...

  14. Supersonic Jet Interactions in a Plenum Chamber

    Directory of Open Access Journals (Sweden)

    K. M. Venugopal

    2004-07-01

    Full Text Available Understanding thè supersonic jet interactions in a plenum chamber is essential for thè design of hot launch systems. Static tests were conducted in a small-scale rocket motor ioaded with a typical nitramine propellaiit to produce a nozzle exit Mach number of 3. This supersonic jet is made to interact with plenum chambers having both open and closed sides. The distance between thè nozzle exit and thè back piate of plenum chamber are varied from 2. 5 to 7. 0 times thè nozzle exit diameter. The pressure rise in thè plenum chamber was measured using pressure transducers mounted at different locatìons. The pressure-time data were analysed to obtain an insight into thè flow field in thè plenum chamber. The maximum pressure exerted on thè back piate of plenum chamber is about 25-35 per cent. of thè maximum stagnation pressure developed in thè rocket motor. Ten static tests were carried out to obtain thè effect of axial distance between thè nozzle exit and thè plenum chamber back piate, and stagnation pressure in thè rocket motoron thè flow field in thè open-sided and closed-sided plenum chambers configurations.

  15. An ionization chamber with magnetic levitated electrodes

    CERN Document Server

    Kawaguchi, T

    1999-01-01

    A new type of ionization chamber which has magnetically levitated electrodes has been developed. The electrodes are supplied voltages for the repelling of ions by a battery which is also levitated with the electrodes. The characteristics of this ionization chamber are investigated in this paper.

  16. ME1/1 Cathode Strip Chambers

    CERN Document Server

    Erchov, Yu V; Kamenev, Alexey; Karjavin, Vladimir; Khabarov, Serguei; Moissenz, P V; Moissenz, K P; Movchan, Sergey; Perelygin, Victor; Vassiliev, S E; Zarubin, Anatoli; Tchekhovski, V A

    2008-01-01

    The 76 innermost ME1/1 cathode strip chambers (CSC) of the CMS Experiment were designed and produced in Dubna. The chambers have been installed in the detector and commissioning has been completed. This paper describes the design of the CSCs, their main mechanical parameters and read-out electronics, and the results of tests with cosmic-ray muons.

  17. HVAC&R Equipment Environmental Chambers

    Data.gov (United States)

    Federal Laboratory Consortium — Description:Large "Truck" ChamberThe large "truck" chamber provides controlled air conditions from -7 °C (20 °F) to 65 °C (150 °F).Air-Conditioner and Heat Pump Test...

  18. Creep in electronic ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Routbort, J. L.; Goretta, K. C.; Arellano-Lopez, A. R.

    2000-04-27

    High-temperature creep measurements combined with microstructural investigations can be used to elucidate deformation mechanisms that can be related to the diffusion kinetics and defect chemistry of the minority species. This paper will review the theoretical basis for this correlation and illustrate it with examples from some important electronic ceramics having a perovskite structure. Recent results on BaTiO{sub 3}, (La{sub 1{minus}x}Sr){sub 1{minus}y}MnO{sub 3+{delta}}, YBa{sub 2}Cu{sub 3}O{sub x}, Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x}, (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} and Sr(Fe,Co){sub 1.5}O{sub x} will be presented.

  19. Low Thermal Expansion Glass Ceramics

    CERN Document Server

    Bach, Hans

    2005-01-01

    This book appears in the authoritative series reporting the international research and development activities conducted by the Schott group of companies. This series provides an overview of Schott's activities for scientists, engineers, and managers from all branches of industry worldwide in which glasses and glass ceramics are of interest. Each volume begins with a chapter providing a general idea of the current problems, results, and trends relating to the subjects treated. This new extended edition describes the fundamental principles, the manufacturing process, and applications of low thermal expansion glass ceramics. The composition, structure, and stability of polycrystalline materials having a low thermal expansion are described, and it is shown how low thermal expansion glass ceramics can be manufactured from appropriately chosen glass compositions. Examples illustrate the formation of this type of glass ceramic by utilizing normal production processes together with controlled crystallization. Thus g...

  20. Bringing Ceramic Parts to Earth

    Institute of Scientific and Technical Information of China (English)

    履之

    1995-01-01

    The benefits of using ceramic engine components are well known:They are tougher than metal parts, weigh less, and can withstand hotter operating temperatures.So why aren’t they being used now? High cost.

  1. Recent progress in ceramic joining

    Energy Technology Data Exchange (ETDEWEB)

    Loehman, R.E.

    1998-09-01

    Both fundamental and practical aspects of ceramic joining are understood well enough for many, if not most, applications requiring moderate strengths at room temperature. This paper argues that the two greatest needs in ceramic joining are for techniques to join buried interfaces by selective heating, and methods for joining ceramics for use at temperatures of 800 to 1,200 C. Heating with microwave radiation or with high-energy electron beams has been used to join buried ceramic interfaces, for example SiC to SiC. Joints with varying levels of strength at temperatures of 600 to 1,000 C have been made using four techniques: (1) transient liquid phase bonding; (2) joining with refractory braze alloys; (3) joining with refractory glass compositions; and (4) joining using preceramic polymers. Joint strengths as high as 550 MPa at 1,000 C have been reported for silicon nitride-silicon nitride bonds tested in four-point flexure.

  2. Microstructure evolution during pressureless sintering of bulk oxide ceramics

    Directory of Open Access Journals (Sweden)

    Karel Maca

    2009-06-01

    Full Text Available The author’s experience concerning the infl uence of the choice of different pressureless heating schedules on the fi nal microstructure of oxide ceramic materials is summarized in the paper. Alumina, ceria, strontium titanate, as well as tetragonal (3 mol% Y2O3 and cubic (8 mol% Y2O3 zirconia were cold isostatically pressed or injection moulded and pressureless sintered with different heating schedules – namely with Constant-Rate of Heating with different dwell temperatures (CRH, with Rate-Controlled Sintering (RCS and with Two-Step Sintering (TSS. It was examined whether some of these three sintering schedules, with the same fi nal density achieved, can lead to a decrease of the grain size of sintered ceramics. The results showed that only TSS (and only for selected materials brought significant decrease of the grain size.

  3. The SAMURAI Time Projection Chamber

    Science.gov (United States)

    Dye, Steven

    2011-10-01

    The SAMURAI Time Projection Chamber (TPC) will be used to study particle collisions by colliding a beam of particles with a stationary gas which will be contained in a field cage inside the TPC. When the beam collides with the gas, charged particles are accelerated into the pad plane by an electric field. The paths of these particles will be curved by a magnetic field created by the SAMURAI magnet at the RIKEN facility in Japan. The charged particles will then collide with the pad plane which will be located on the bottom of the TPC. The pad plane will take these collisions and create electrical signals and send them to supporting electronics where the data can be interpreted. The TPC will be used to help determine the Equation of State for asymmetric nuclear matter. Measurements of neutron, proton, 3H and 3He flow will be taken with the NEBULA array which consists of nebula scintillators. The poster will contain information on the laser calibration system and the electronics that will be used for the TPC. The electronics used are the same electronics used in the STAR TPC experiment.

  4. The CAST time projection chamber

    Science.gov (United States)

    Autiero, D.; Beltrán, B.; Carmona, J. M.; Cebrián, S.; Chesi, E.; Davenport, M.; Delattre, M.; Di Lella, L.; Formenti, F.; Irastorza, I. G.; Gómez, H.; Hasinoff, M.; Lakic, B.; Luzón, G.; Morales, J.; Musa, L.; Ortiz, A.; Placci, A.; Rodrigurez, A.; Ruz, J.; Villar, J. A.; Zioutas, K.

    2007-06-01

    One of the three x-ray detectors of the CERN Axion Solar Telescope (CAST) experiment searching for solar axions is a time projection chamber (TPC) with a multi-wire proportional counter (MWPC) as a readout structure. Its design has been optimized to provide high sensitivity to the detection of the low intensity x-ray signal expected in the CAST experiment. A low hardware threshold of 0.8 keV is set to a safe level during normal data taking periods, and the overall efficiency for the detection of photons coming from conversion of solar axions is 62%. Shielding has been installed around the detector, lowering the background level to 4.10 × 10-5 counts cm-2 s-1 keV-1 between 1 and 10 keV. During phase I of the CAST experiment the TPC has provided robust and stable operation, thus contributing with a competitive result to the overall CAST limit on axion photon coupling and mass.

  5. Ceramic Forum International yearbook 2005

    Energy Technology Data Exchange (ETDEWEB)

    Reh, H. (ed.)

    2004-12-01

    This is the second English-language edition of our 'ceramic forum international Yearbook'. In this year's 'Ceramics World', the perpetually updated textbook section, you will find papers surveying the already in technical ceramics established fields of 'bioceramics' and 'ceramic armouring'. From the traditional ceramics sector, from which news of more and more innovations have been reaching us in recent months, we have picked out 'decorating processes for ceramic tiles' as these are currently enjoying an undreamt-of boom thanks to the development of completely new shaping processes. A soundly researched study on 'rheology in ceramics' completes this section of the yearbook. Interested ceramists will again find everything they need for their day-to-day work - the index will help them to find the information they need fast. This information is available under the following headings: (A) Product News: Short notes on outstanding new machines, kilns, plants and equipment as well as new raw materials on the market, supplied by both European and overseas suppliers. (B) Abstracts: A compilation of abridged articles, all of which published during the last 12 months, discussing interesting processes and products or new directions in research. (C) ESD - European Suppliers Directory: Who supplies what? In English, German, Spanish, Italian and French with about 220 company entries. (D) Appendix: Listing ceramics laboratories in Europe; the periodic system; the most important physical units and the conversion of older ones to SI units (and vice versa); essential formulas for use in the ceramist's daily practice. (orig.)

  6. Method for preparing ceramic composite

    Science.gov (United States)

    Alexander, Kathleen B.; Tiegs, Terry N.; Becher, Paul F.; Waters, Shirley B.

    1996-01-01

    A process for preparing ceramic composite comprising blending TiC particulates, Al.sub.2 O.sub.3 particulates and nickle aluminide and consolidating the mixture at a temperature and pressure sufficient to produce a densified ceramic composite having fracture toughness equal to or greater than 7 MPa m.sup.1/2, a hardness equal to or greater than 18 GPa.

  7. Nano-Ceramic Coated Plastics

    Science.gov (United States)

    Cho, Junghyun

    2013-01-01

    Plastic products, due to their durability, safety, and low manufacturing cost, are now rapidly replacing cookware items traditionally made of glass and ceramics. Despite this trend, some still prefer relatively expensive and more fragile ceramic/glassware because plastics can deteriorate over time after exposure to foods, which can generate odors, bad appearance, and/or color change. Nano-ceramic coatings can eliminate these drawbacks while still retaining the advantages of the plastic, since the coating only alters the surface of the plastic. The surface coating adds functionality to the plastics such as self-cleaning and disinfectant capabilities that result from a photocatalytic effect of certain ceramic systems. These ceramic coatings can also provide non-stick surfaces and higher temperature capabilities for the base plastics without resorting to ceramic or glass materials. Titanium dioxide (TiO2) and zinc oxide (ZnO) are the candidates for a nano-ceramic coating to deposit on the plastics or plastic films used in cookware and kitchenware. Both are wide-bandgap semiconductors (3.0 to 3.2 eV for TiO2 and 3.2 to 3.3 eV for ZnO), so they exhibit a photocatalytic property under ultraviolet (UV) light. This will lead to decomposition of organic compounds. Decomposed products can be easily washed off by water, so the use of detergents will be minimal. High-crystalline film with large surface area for the reaction is essential to guarantee good photocatalytic performance of these oxides. Low-temperature processing (nano-ceramic coatings (TiO2, ZnO) on plastic materials (silicone, Teflon, PET, etc.) that can possess both photocatalytic oxide properties and flexible plastic properties. Processing cost is low and it does not require any expensive equipment investment. Processing can be scalable to current manufacturing infrastructure.

  8. Windows Into an Open-System Magma Chamber: Cognate Xenoliths From the Kameni Islands, Santorini, Greece

    Science.gov (United States)

    Martin, V. M.; Holness, M. B.; Pyle, D. M.

    2003-12-01

    The composition of the dacite forming the Kameni Islands has been remarkably uniform over the last 2200 years, attesting to significant replenishment and mixing in the shallow open-system chamber. Insights into chamber evolution can be gained from the abundant cognate xenoliths in the dacite. The xenoliths include both cumulates from the chamber floor and quenched fragments of replenishing magma. They fall into 7 groups distinguishable by differences in chemistry, texture and mechanical behaviour. Quench xenoliths with linear CSDs are thought to have formed on the injection of aphyric magma into the chamber. Since these xenoliths commonly have an andesitic composition, this suggests the expulsion of an aphyric melt from a crystal mush in a lower chamber by filter-pressing during compaction. Those with strongly bi-modal grain size distributions indicate injection of phenocryst-bearing replenishing magma. Quench xenoliths with evolved compositions are typically found as large isolated blocks randomly dispersed throughout the host lava. In contrast, the more mafic xenoliths are distributed in tight, elongate, clusters aligned in the direction of flow, and comprising up to 100 individuals. The contrasting spatial distributions of the xenoliths reflects the different rheological properties of the xenolith types, with implications for the ease of mixing and assimilation of batches of replenishing melt in the magma chamber. The rare cumulate xenoliths are small, and are characterised by coarse grain-size, low glass and vesicle content, and are predominantly found in lava from the last (1950) eruption. They are generally found enveloped by less dense and highly vesicular quench-type xenoliths, which probably provided the buoyancy forces necessary for entrainment. Mapping of the xenolith types shows that each flow forming the Kameni Islands has a distinct xenolith population, reflecting the changing state of the emptying magma chamber. Seismic activity has preceded most

  9. Ceramic materials and growth factors

    Energy Technology Data Exchange (ETDEWEB)

    Ohgushi, H.; Yoshikawa, T.; Okumura, M.; Nakajima, H.; Takakura, Y. [Nara Medical Univ. (Japan). Dept. of Orhtopaedic Surgery; Dohi, Y. [Nara Medical Univ. (Japan). Dept. of Public Health; Noshi, T.; Ikeuchi, M. [Nara Medical Univ. (Japan). Dept. of Oral and Maxillofacial Surgery

    2001-07-01

    Recently, many types of growth factors have been purified and used for promoting cell differentiation cascade. The activity of growth factors can be detected in vitro such as culture condition. However, the activity is difficult to detect when these factors are locally administered in vivo, because these dissipate soon after the administration. In order to retain growth factors in local milieu, these can be incorporated with biocompatible porous ceramic materials. Such ceramic/factors composites when implanted in vivo, can trigger certain types of cell differentiation cascade resulted in new tissue formation and tissue regeneration. The paper describes the ceramic / growth factors composites especially hydroxyapatite ceramic (HA) / bone morphogenetic protein (BMP) composite to induce osteoblastic differentiation of mesenchymal stem cells. The HA/BMP composite supported the osteoblastic differentiation on the HA surface and finally resulted in bone bonding to the HA. When the marrow mesenchymal stem cells (MSCs) were impregnated in pore areas of HA ceramics, the composites showed more and rapid bone formation than the HA/BMP and HA/MSCs composite, indicating the synergistic effect of BMP and MSCs. These findings indicate the importance of ceramic surface to evoke osteoblastic differentiation as well as to capture the molecules of growth factors for the cell differentiation. (orig.)

  10. Microwave sintering of ceramic materials

    Science.gov (United States)

    Karayannis, V. G.

    2016-11-01

    In the present study, the potential of microwave irradiation as an innovative energy- efficient alternative to conventional heating technologies in ceramic manufacturing is reviewed, addressing the advantages/disadvantages, while also commenting on future applications of possible commercial interest. Ceramic materials have been extensively studied and used due to several advantages they exhibit. Sintering ceramics using microwave radiation, a novel technology widely employed in various fields, can be an efficient, economic and environmentally-friendlier approach, to improve the consolidation efficiency and reduce the processing cycle-time, in order to attain substantial energy and cost savings. Microwave sintering provides efficient internal heating, as energy is supplied directly and penetrates the material. Since energy transfer occurs at a molecular level, heat is generated throughout the material, thus avoiding significant temperature gradients between the surface and the interior, which are frequently encountered at high heating rates upon conventional sintering. Thus, rapid, volumetric and uniform heating of various raw materials and secondary resources for ceramic production is possible, with limited grain coarsening, leading to accelerated densification, and uniform and fine-grained microstructures, with enhanced mechanical performance. This is particularly important for manufacturing large-size ceramic products of quality, and also for specialty ceramic materials such as bioceramics and electroceramics. Critical parameters for the process optimization, including the electromagnetic field distribution, microwave-material interaction, heat transfer mechanisms and material transformations, should be taken into consideration.

  11. Effects of supercritical environment on hydrocarbon-fuel injection

    Science.gov (United States)

    Shin, Bongchul; Kim, Dohun; Son, Min; Koo, Jaye

    2017-04-01

    In this study, the effects of environment conditions on decane were investigated. Decane was injected in subcritical and supercritical ambient conditions. The visualization chamber was pressurized to 1.68 MPa by using nitrogen gas at a temperature of 653 K for subcritical ambient conditions. For supercritical ambient conditions, the visualization chamber was pressurized to 2.52 MPa by using helium at a temperature of 653 K. The decane injection in the pressurized chamber was visualized via a shadowgraph technique and gradient images were obtained by a post processing method. A large variation in density gradient was observed at jet interface in the case of subcritical injection in subcritical ambient conditions. Conversely, for supercritical injection in supercritical ambient conditions, a small density gradient was observed at the jet interface. In a manner similar to that observed in other cases, supercritical injection in subcritical ambient conditions differed from supercritical ambient conditions such as sphere shape liquid. Additionally, there were changes in the interface, and the supercritical injection core width was thicker than that in the subcritical injection. Furthermore, in cases with the same injection conditions, the change in the supercritical ambient normalized core width was smaller than the change in the subcritical ambient normalized core width owing to high specific heat at the supercritical injection and small phase change at the interface. Therefore, the interface was affected by the changing ambient condition. Given that the effect of changing the thermodynamic properties of propellants could be essential for a variable thrust rocket engine, the effects of the ambient conditions were investigated experimentally.

  12. Ferroelectric ceramics in a pyroelectric accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Shchagin, A. V., E-mail: shchagin@kipt.kharkov.ua [Kharkov Institute of Physics and Technology, Kharkov 61108 (Ukraine); Belgorod State University, Belgorod 308015 (Russian Federation); Miroshnik, V. S.; Volkov, V. I. [Kharkov Institute of Physics and Technology, Kharkov 61108 (Ukraine); Oleinik, A. N. [Belgorod State University, Belgorod 308015 (Russian Federation)

    2015-12-07

    The applicability of polarized ferroelectric ceramics as a pyroelectric in a pyroelectric accelerator is shown by experiments. The spectra of X-ray radiation of energy up to tens of keV, generated by accelerated electrons, have been measured on heating and cooling of the ceramics in vacuum. It is suggested that curved layers of polarized ferroelectric ceramics be used as elements of ceramic pyroelectric accelerators. Besides, nanotubes and nanowires manufactured from ferroelectric ceramics are proposed for the use in nanometer-scale ceramic pyroelectric nanoaccelerators for future applications in nanotechnologies.

  13. On Maximal Injectivity

    Institute of Scientific and Technical Information of China (English)

    Ming Yi WANG; Guo ZHAO

    2005-01-01

    A right R-module E over a ring R is said to be maximally injective in case for any maximal right ideal m of R, every R-homomorphism f : m → E can be extended to an R-homomorphism f' : R → E. In this paper, we first construct an example to show that maximal injectivity is a proper generalization of injectivity. Then we prove that any right R-module over a left perfect ring R is maximally injective if and only if it is injective. We also give a partial affirmative answer to Faith's conjecture by further investigating the property of maximally injective rings. Finally, we get an approximation to Faith's conjecture, which asserts that every injective right R-module over any left perfect right self-injective ring R is the injective hull of a projective submodule.

  14. Storing Waste in Ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Bourcier, W L; Sickafus, K

    2004-07-20

    Not all the nuclear waste destined for Yucca Mountain is in the form of spent fuel. Some of it will be radioactive waste generated from the production of nuclear weapons. This so-called defense waste exists mainly as corrosive liquids and sludge in underground tanks. An essential task of the U.S. high-level radioactive waste program is to process these defense wastes into a solid material--called a waste form. An ideal waste form would be extremely durable and unreactive with other repository materials. It would be simple to fabricate remotely so that it could be safely transported to a repository for permanent storage. What's more, the material should be able to tolerate exposure to intense radiation without degradation. And to minimize waste volume, the material must be able to contain high concentrations of radionuclides. The material most likely to be used for immobilization of radioactive waste is glass. Glasses are produced by rapid cooling of high-temperature liquids such that the liquid-like non-periodic structure is preserved at lower temperatures. This rapid cooling does not allow enough time for thermodynamically stable crystalline phases (mineral species) to form. In spite of their thermodynamic instability, glasses can persist for millions of years. An alternate to glass is a ceramic waste form--an assemblage of mineral-like crystalline solids that incorporate radionuclides into their structures. The crystalline phases are thermodynamically stable at the temperature of their synthesis; ceramics therefore tend to be more durable than glasses. Ceramic waste forms are fabricated at temperatures below their melting points and so avoid the danger of handling molten radioactive liquid--a danger that exists with incorporation of waste in glasses. The waste form provides a repository's first line of defense against release of radionuclides. It, along with the canister, is the barrier in the repository over which we have the most control. When a waste

  15. Monitored Drift Chambers in the ATLAS Detector

    CERN Multimedia

    Herten, G

    Monitored Drift Chambers (MDT) are used in the ATLAS Detector to measure the momentum of high energy muons. They consist of drift tubes, which are filled with an Ar-CO2 gas mixture at 3 bar gas pressure. About 1200 drift chambers are required for ATLAS. They are up to 6 m long. Nevertheless the position of every wire needs to be known with a precision of 20 µm within a chamber. In addition, optical alignment sensors are required to measure the relative position of adjacent chambers with a precision of 30µm. This gigantic task seems impossible at first instance. Indeed it took many years of R&D to invent the right tools and methods before the first chamber could be built according to specifications. Today, at the time when 50% of the chambers have been produced, we are confident that the goal for ATLAS can be reached. The mechanical precision of the chambers could be verified with the x-ray tomograph at CERN. This ingenious device, developed for the MDT system, is able to measure the wire position insid...

  16. Making MUSIC: A multiple sampling ionization chamber

    Energy Technology Data Exchange (ETDEWEB)

    Shumard, B. [Argonne National Laboratory, Building 203 H-113, Argonne, IL 60439 (United States)]. E-mail: shumard@phy.anl.gov; Henderson, D.J. [Argonne National Laboratory, Building 203 H-113, Argonne, IL 60439 (United States); Rehm, K.E. [Argonne National Laboratory, Building 203 H-113, Argonne, IL 60439 (United States); Tang, X.D. [Argonne National Laboratory, Building 203 H-113, Argonne, IL 60439 (United States)

    2007-08-15

    A multiple sampling ionization chamber (MUSIC) was developed for use in conjunction with the Atlas scattering chamber (ATSCAT). This chamber was developed to study the ({alpha}, p) reaction in stable and radioactive beams. The gas filled ionization chamber is used as a target and detector for both particles in the outgoing channel (p + beam particles for elastic scattering or p + residual nucleus for ({alpha}, p) reactions). The MUSIC detector is followed by a Si array to provide a trigger for anode events. The anode events are gated by a gating grid so that only ({alpha}, p) reactions where the proton reaches the Si detector result in an anode event. The MUSIC detector is a segmented ionization chamber. The active length of the chamber is 11.95 in. and is divided into 16 equal anode segments (3.5 in. x 0.70 in. with 0.3 in. spacing between pads). The dead area of the chamber was reduced by the addition of a Delrin snout that extends 0.875 in. into the chamber from the front face, to which a mylar window is affixed. 0.5 in. above the anode is a Frisch grid that is held at ground potential. 0.5 in. above the Frisch grid is a gating grid. The gating grid functions as a drift electron barrier, effectively halting the gathering of signals. Setting two sets of alternating wires at differing potentials creates a lateral electric field which traps the drift electrons, stopping the collection of anode signals. The chamber also has a reinforced mylar exit window separating the Si array from the target gas. This allows protons from the ({alpha}, p) reaction to be detected. The detection of these protons opens the gating grid to allow the drift electrons released from the ionizing gas during the ({alpha}, p) reaction to reach the anode segment below the reaction.

  17. Performance of Ceramics in Severe Environments

    Science.gov (United States)

    Jacobson, Nathan S.; Fox, Dennis S.; Smialek, James L.; Deliacorte, Christopher; Lee, Kang N.

    2005-01-01

    Ceramics are generally stable to higher temperatures than most metals and alloys. Thus the development of high temperature structural ceramics has been an area of active research for many years. While the dream of a ceramic heat engine still faces many challenges, niche markets are developing for these materials at high temperatures. In these applications, ceramics are exposed not only to high temperatures but also aggressive gases and deposits. In this chapter we review the response of ceramic materials to these environments. We discuss corrosion mechanisms, the relative importance of a particular corrodent, and, where available, corrosion rates. Most of the available corrosion information is on silicon carbide (SIC) and silicon nitride (Si3N4) monolithic ceramics. These materials form a stable film of silica (SO2) in an oxidizing environment. We begin with a discussion of oxidation of these materials and proceed to the effects of other corrodents such as water vapor and salt deposits. We also discuss oxidation and corrosion of other ceramics: precurser derived ceramics, ceramic matrix composites (CMCs), ceramics which form oxide scales other than silica, and oxide ceramics. Many of the corrosion issues discussed can be mitigated with refractory oxide coatings and we discuss the current status of this active area of research. Ultimately, the concern of corrosion is loss of load bearing capability. We discuss the effects of corrosive environments on the strength of ceramics, both monolithic and composite. We conclude with a discussion of high temperature wear of ceramics, another important form of degradation at high temperatures.

  18. Leakage Current Phenomenon on Ceramics and Epoxy Resin as 20 kV Outdoor Insulator at Tropical Environment

    Directory of Open Access Journals (Sweden)

    Valdi Rizki Yandri

    2011-01-01

    Full Text Available This paper explains the research results of  leakage current, hydrophobicity and flashover voltage comparison on ceramics and epoxy  resin 20 kV outdoor insulator in a  chamber at tropical climate conditions. The waveform of leakage current (LC was measured using a digital oscilloscope. The digital data was transferred to a personal computer using a RS-232 cable. The digital data was analyzed using Fast Fourier Transform. The result showed that LC was affected by various environment conditions like temperature, humidity and pollution. LC of ceramics insulator was higher than epoxy resin insulator in low temperature, high humidity and high pollution condition.

  19. Sample chambers with mother-daughter mode

    Energy Technology Data Exchange (ETDEWEB)

    Wilk, P.A.; Gregorich, K.E.; Hoffman, D.C.

    2001-07-12

    A set of eight stand-alone sample chambers with a common interface were constructed at LBNL for improved detection of alpha and fission decay chains over currently used designs. The stainless steel chambers (see Figure 1 for a schematic and Figure 2 for a photograph of a completed chamber) were constructed to allow for low background detection of a daughter event by removal of the sample following the detection of a parent event. This mother-daughter mode of operation has been utilized successfully with our Merry-go-Round (MG) detection system [Gregorich 1994].

  20. Radiation-induced foil electret chamber

    Science.gov (United States)

    Fallone, B. G.; Podgorsak, E. B.

    1983-10-01

    Saturation current densities, extrapolated electric fields, and electret-charging and -discharging current-density profiles in an ionization electret chamber are discussed as a function of various chamber parameters, such as air-gap and polymer thickness, polarizing electrode material, exposure rate, etc. Both the saturation current density and the extrapolated electric field consist of two components; one is linear with the air-gap thickness and is attributed to primary ionization in air, and the other exhibits exponential saturation and is attributed to air ionization caused by photoelectrons backscattered into the chamber sensitive volume from the polarizing electrode.

  1. LEP vacuum chamber, cross-section

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    Cross-section of the final prototype for the LEP vacuum chamber. The elliptic main-opening is for the beam. The small channel to the left is for the cooling water, to carry away the heat deposited by the synchrotron radiation. The square channel to the right houses the Non-Evaporable Getter (NEG) pump. The chamber is made from extruded aluminium. Its outside is clad with lead, to stop the synchrotron radiation emitted by the beam. For good adherence between Pb and Al, the Al chamber was coated with a thin layer of Ni. Ni being slightly magnetic, some resulting problems had to be overcome. See also 8301153.

  2. Bubble chamber: Omega production and decay

    CERN Multimedia

    1973-01-01

    This image is of real particle tracks taken from the CERN 2 m liquid hydrogen bubble chamber and shows the production and decay of a negative omega particle. A negative kaon enters the chamber which decays into many particles, including a negative omega that travels a short distance before decaying into more particles. The invention of bubble chambers in 1952 revolutionized the field of particle physics, allowing real tracks left by particles to be seen and photographed by expanding liquid that had been heated to boiling point.

  3. A mathematical model of aerosol holding chambers

    DEFF Research Database (Denmark)

    Zak, M; Madsen, J; Berg, E

    1999-01-01

    in the chamber with time. Four different spacers were connected via filters to a mechanical lung model, and aerosol delivery during "breathing" was determined from drug recovery from the filters. The formula correctly predicted the delivery of budesonide aerosol from the AeroChamber (Trudell Medical, London......, Ontario, Canada), NebuChamber (Astra, Södirtälje, Sweden) and Nebuhaler (Astra) adapted for babies. The dose of fluticasone proportionate delivered by the Babyhaler (Glaxco Wellcome, Oxbridge, Middlesex, UK) was 80% of that predicted, probably because of incomplete priming of this spacer. Of the above...

  4. Weld Development for Aluminum Fission Chamber

    Energy Technology Data Exchange (ETDEWEB)

    Cross, Carl Edward [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Martinez, Jesse Norris [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-05-16

    The Sigma welding team was approached to help fabricate a small fission chamber (roughly ½ inch dia. x ½ inch tall cylinder). These chambers are used as radiation sensors that contain small traces of radionuclides (Cf 252, U 235, and U 238) that serve to ionize gas atoms in addition to external radiation. When a voltage is applied within the chamber, the resulting ion flow can be calibrated and monitored. Aluminum has the advantage of not forming radioactive compounds when exposed to high external radiation (except from minor Na alloy content). Since aluminum has not been used before in this application, this presented an unexplored challenge.

  5. APS Storage Ring vacuum chamber fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Goeppner, G.A.

    1990-01-01

    The 1104-m circumference Advanced Photon Source Storage Ring Vacuum System is composed of 240 individual sections, which are fabricated from a combination of aluminum extrusions and machined components. The vacuum chambers will have 3800 weld joints, each subject to strict vacuum requirements, as well as a variety of related design criteria. The vacuum criteria and chamber design are reviewed, including a discussion of the weld joint geometries. The critical fabrication process parameters for meeting the design requirements are discussed. The experiences of the prototype chamber fabrication program are presented. Finally, the required facilities preparation for construction activity is briefly described. 6 refs., 6 figs., 1 tab.

  6. 30 CFR 77.305 - Access to drying chambers, hot gas inlet chambers and ductwork; installation and maintenance.

    Science.gov (United States)

    2010-07-01

    ... chambers and ductwork; installation and maintenance. 77.305 Section 77.305 Mineral Resources MINE SAFETY... drying chambers, hot gas inlet chambers and ductwork; installation and maintenance. Drying chambers, hot gas inlet chambers and all ductwork in which coal dust may accumulate shall be equipped with...

  7. High incidence of squeaking in THAs with alumina ceramic-on-ceramic bearings.

    NARCIS (Netherlands)

    Keurentjes, J.C.; Kuipers, R.M.; Wever, D.J.; Schreurs, B.W.

    2008-01-01

    Ceramic-on-ceramic bearings in THA are a popular alternative to overcome wear concerns in traditional metal-polyethylene bearings. However, squeaking is a potentially worrisome phenomenon in ceramic-on-ceramic THAs which we observed in some of our patients. We reviewed all 42 patients who underwent

  8. FY 1998 annual report. Research and development on ceramic gas turbine (300kW class)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-04-01

    Research and development have been made on a small ceramic gas turbine which is high in efficiency, low in pollutant emission, capable of corresponding to different fuels, and can be utilized in cogeneration and/or movable electric power generation systems. Fundamental researches in developing and researching heat resistant ceramic parts have been carried out on a method for fabricating turbine nozzles using heat resistant silicon nitride, improvement in accuracy in fabricating combustors using the heat resistant silicon nitride, and casting of turbine blades made from sialon. In developing the devices, researches were made on reliability of bond between a ceramic blade and a metallic disk, air-fuel ratio in a combustor, distribution of fuel concentrations, fuel injection methods, reduction of loss in a diffuser in a compressor, and matching of the diffuser with an impeller. In addition, research and development were performed on a single shaft ceramic gas turbine for cogeneration and a double shaft ceramic gas turbine. Researches were executed on reliability of ceramic materials. (NEDO)

  9. Numerical modeling of a Jet Ignition Direct Injection (JIDI) LPG engine

    OpenAIRE

    albert boretti

    2016-01-01

    The paper presents indirectly validated simulations of the operation of a LPG engine fitted with Direct Injection (DI) and Jet Ignition (JI). It is demonstrated that the engine may have diesel like efficiencies and load control by quantity of fuel injected.  As the liquid propane quickly evaporates after injection in the main chamber, the main chamber mixture may be much closer to stoichiometry than a diesel for a better specific power at low engine speeds. This design also works at the high ...

  10. III Advanced Ceramics and Applications Conference

    CERN Document Server

    Gadow, Rainer; Mitic, Vojislav; Obradovic, Nina

    2016-01-01

    This is the Proceedings of III Advanced Ceramics and Applications conference, held in Belgrade, Serbia in 2014. It contains 25 papers on various subjects regarding preparation, characterization and application of advanced ceramic materials.

  11. Origin and Development of Chinese Ceramics

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    CERAMICS is animportant partof traditionalChinese culture and re-flects the wisdomand creativity of theCinese people.Kilnsfrom many differentdynasties have fired anumber of ceramic arti-cles of high artistic val-

  12. Panel report on high temperature ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Nolet, T C [ed.

    1979-01-01

    Fundamental research is reported concerning high temperature ceramics for application in turbines, engines, batteries, gasifiers, MHD, fuel cells, heat exchangers, and hot wall combustors. Ceramics microstructure and behavior are included. (FS)

  13. Epoetin Alfa Injection

    Science.gov (United States)

    ... Combivir), a medication used to treat human immunodeficiency virus (HIV). Epoetin alfa injection is also used before ... inject epoetin alfa, as directed by your doctor. Write down the date, time, dose of epoetin alfa ...

  14. Collagenase Clostridium Histolyticum Injection

    Science.gov (United States)

    Collagenase Clostridium histolyticum injection is used to treat Dupuytren's contracture (a painless thickening and tightening of tissue [cord] beneath ... of tissue can be felt upon examination. Collagenase Clostridium histolyticum injection is also used to treat Peyronie's ...

  15. Iron Sucrose Injection

    Science.gov (United States)

    Iron sucrose injection is used treat iron-deficiency anemia (a lower than normal number of red blood cells due ... and may cause the kidneys to stop working). Iron sucrose injection is in a class of medications called iron ...

  16. Intracytoplasmic sperm injection

    Science.gov (United States)

    Intracytoplasmic sperm injection, or ICSI, is a form of in vitro fertilization in which fertilization occurs outside of the ... laboratory dish. Within a few hours, a single sperm is injected through a fine needle into the ...

  17. Sodium Ferric Gluconate Injection

    Science.gov (United States)

    Sodium ferric gluconate injection is used to treat iron-deficiency anemia (a lower than normal number of ... are also receiving the medication epoetin (Epogen, Procrit). Sodium ferric gluconate injection is in a class of ...

  18. Calcitonin Salmon Injection

    Science.gov (United States)

    Calcitonin salmon injection is used to treat osteoporosis in postmenopausal women. Osteoporosis is a disease that causes bones to weaken and break more easily. Calcitonin salmon injection is also used to treat Paget's disease ...

  19. Other Injectable Medications

    Science.gov (United States)

    ... July 17, 2013 Last Edited: February 22, 2017 Articles from Diabetes Forecast® magazine: cg-infusion-sets,meds-bg-injectables,cg-injection-aids, In this section Treatment and Care Medication Insulin & ...

  20. Injection losses and protection

    CERN Document Server

    Bartmann, W; Baudrenghien, P; Bracco, C; Dehning, B; Di Mauro, A; Drosdal, L; Emery, J; Goddard, B; Holzer, E B; Höfle, W; Kain, V; Meddahi, M; Radaelli, S; Shaposhnilova, E; Uythoven, J; Valuch, D; Wenninger, J; Zamantzas, C; Gianfelice-Wendt, E

    2012-01-01

    Injection losses are compared for 2010 and 2011 operation. Mitigation techniques which were put in place in 2010 to reduce losses at injection are described. Issues in 2011 operation, their potential improvements and the performance reach for 2012 are shown.

  1. Numerical modeling of a Jet Ignition Direct Injection (JIDI LPG engine

    Directory of Open Access Journals (Sweden)

    albert boretti

    2016-12-01

    Full Text Available The paper presents indirectly validated simulations of the operation of a LPG engine fitted with Direct Injection (DI and Jet Ignition (JI. It is demonstrated that the engine may have diesel like efficiencies and load control by quantity of fuel injected.  As the liquid propane quickly evaporates after injection in the main chamber, the main chamber mixture may be much closer to stoichiometry than a diesel for a better specific power at low engine speeds. This design also works at the high engine speeds impossible for the diesel, as combustion within the main chamber is controlled by the turbulent mixing rather than the vaporization and diffusion processes of the injected fuel of the diesel. 

  2. Ordered ceramic membranes

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, M.A.; Hill, C.G. Jr.; Zeltner, W.A.

    1991-10-01

    Ceramic membranes have been formed from colloidal sols coated on porous clay supports. These supported membranes have been characterized in terms of their permeabilities and permselectivities to various aqueous test solutions. The thermal stabilities and pore structures of these membranes have been characterized by preparing unsupported membranes of the correpsonding material and performing N{sub 2} adsorption-desorption and X-ray diffraction studies on these membranes. To date, membranes have been prepared from a variety of oxides, including TiO{sub 2}, SiO{sub 2}, ZrO{sub 2}, and Al{sub 2}O{sub 3}, as well as Zr-, Fe-, and Nb-doped TiO{sub 2}. In many of these membranes pore diameters are less than 2 nm, while in others the pore diameters are between 3 and 5 nm. Procedures for fabricating porous clay supports with reproducible permeabilities for pure water are also discussed. 30 refs., 59 figs., 22 tabs.

  3. Bar piezoelectric ceramic transformers.

    Science.gov (United States)

    Erhart, Jiří; Pulpan, Půlpán; Rusin, Luboš

    2013-07-01

    Bar-shaped piezoelectric ceramic transformers (PTs) working in the longitudinal vibration mode (k31 mode) were studied. Two types of the transformer were designed--one with the electrode divided into two segments of different length, and one with the electrodes divided into three symmetrical segments. Parameters of studied transformers such as efficiency, transformation ratio, and input and output impedances were measured. An analytical model was developed for PT parameter calculation for both two- and three-segment PTs. Neither type of bar PT exhibited very high efficiency (maximum 72% for three-segment PT design) at a relatively high transformation ratio (it is 4 for two-segment PT and 2 for three-segment PT at the fundamental resonance mode). The optimum resistive loads were 20 and 10 kΩ for two- and three-segment PT designs for the fundamental resonance, respectively, and about one order of magnitude smaller for the higher overtone (i.e., 2 kΩ and 500 Ω, respectively). The no-load transformation ratio was less than 27 (maximum for two-segment electrode PT design). The optimum input electrode aspect ratios (0.48 for three-segment PT and 0.63 for two-segment PT) were calculated numerically under no-load conditions.

  4. Disc piezoelectric ceramic transformers.

    Science.gov (United States)

    Erhart, Jirií; Půlpán, Petr; Doleček, Roman; Psota, Pavel; Lédl, Vít

    2013-08-01

    In this contribution, we present our study on disc-shaped and homogeneously poled piezoelectric ceramic transformers working in planar-extensional vibration modes. Transformers are designed with electrodes divided into wedge, axisymmetrical ring-dot, moonie, smile, or yin-yang segments. Transformation ratio, efficiency, and input and output impedances were measured for low-power signals. Transformer efficiency and transformation ratio were measured as a function of frequency and impedance load in the secondary circuit. Optimum impedance for the maximum efficiency has been found. Maximum efficiency and no-load transformation ratio can reach almost 100% and 52 for the fundamental resonance of ring-dot transformers and 98% and 67 for the second resonance of 2-segment wedge transformers. Maximum efficiency was reached at optimum impedance, which is in the range from 500 Ω to 10 kΩ, depending on the electrode pattern and size. Fundamental vibration mode and its overtones were further studied using frequency-modulated digital holographic interferometry and by the finite element method. Complementary information has been obtained by the infrared camera visualization of surface temperature profiles at higher driving power.

  5. Ceramic HEPA Filter Program

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, M A; Bergman, W; Haslam, J; Brown, E P; Sawyer, S; Beaulieu, R; Althouse, P; Meike, A

    2012-04-30

    Potential benefits of ceramic filters in nuclear facilities: (1) Short term benefit for DOE, NRC, and industry - (a) CalPoly HTTU provides unique testing capability to answer questions for DOE - High temperature testing of materials, components, filter, (b) Several DNFSB correspondences and presentations by DNFSB members have highlighted the need for HEPA filter R and D - DNFSB Recommendation 2009-2 highlighted a nuclear facility response to an evaluation basis earthquake followed by a fire (aka shake-n-bake) and CalPoly has capability for a shake-n-bake test; (2) Intermediate term benefit for DOE and industry - (a) Filtration for specialty applications, e.g., explosive applications at Nevada, (b) Spin-off technologies applicable to other commercial industries; and (3) Long term benefit for DOE, NRC, and industry - (a) Across industry, strong desire for better performance filter, (b) Engineering solution to safety problem will improve facility safety and decrease dependence on associated support systems, (c) Large potential life-cycle cost savings, and (d) Facilitates development and deployment of LLNL process innovations to allow continuous ventilation system operation during a fire.

  6. Antiferroelectric Shape Memory Ceramics

    Directory of Open Access Journals (Sweden)

    Kenji Uchino

    2016-05-01

    Full Text Available Antiferroelectrics (AFE can exhibit a “shape memory function controllable by electric field”, with huge isotropic volumetric expansion (0.26% associated with the AFE to Ferroelectric (FE phase transformation. Small inverse electric field application can realize the original AFE phase. The response speed is quick (2.5 ms. In the Pb0.99Nb0.02[(Zr0.6Sn0.41-yTiy]0.98O3 (PNZST system, the shape memory function is observed in the intermediate range between high temperature AFE and low temperature FE, or low Ti-concentration AFE and high Ti-concentration FE in the composition. In the AFE multilayer actuators (MLAs, the crack is initiated in the center of a pair of internal electrodes under cyclic electric field, rather than the edge area of the internal electrodes in normal piezoelectric MLAs. The two-sublattice polarization coupling model is proposed to explain: (1 isotropic volume expansion during the AFE-FE transformation; and (2 piezoelectric anisotropy. We introduce latching relays and mechanical clampers as possible unique applications of shape memory ceramics.

  7. Incorporation of Waste Ceramic Blocks in Structural Ceramics

    Science.gov (United States)

    de Oliveira, Orley Magalhães; das Graças da Silva-Valenzuela, Maria; Andrade, Christiano Gianesi Bastos; Junior, Antonio Hortêncio Munhoz; Valenzuela-Díaz, Francisco Rolando

    In Brazil, Ceramics Industries produce bricks and ceramic tiles in practically all the country. In the southwestern region of Bahia are located some of these industries. A considerable proportion of the material produced do not pass the quality control for not having a uniform visual appearance or have cracks. These burned pieces are generally discarded, resulting in a big quantity of waste. The objective of this work is the characterization of this industrial waste and thus consign them to other industrial applications. Our results demonstrate that the burned waste have potential to be used for incorporation in common clay for structural ceramics, thereby avoiding its disposal in nature and reducing this environmental liability. Experimental bodies were tested with different quantities of waste. The common clay and the burned waste were characterized by XRD, TG/DTA, and SEM. The burned specimens were tested for mechanical strength, water absorption, bulk density, and apparent porosity. An incorporation of 10% of waste furnished the best results.

  8. Developing cloud chambers with high school students

    CERN Document Server

    Ishizuka, Ryo; Sato, Shoma; Zeze, Syoji

    2013-01-01

    The result and outcome of the cloud chamber project, which aims to develop a cloud chamber useful for science education is reported in detail. A project includes both three high school students and a teacher as a part of Super Science High School (SSH) program in our school. We develop a dry ice free cloud chamber using salt and ice (or snow). Technical detail of the chamber is presented. We also argue how the project affects student's cognition, motivation, academic skills and behavior. The research project had been done in very similar way to those of professional researchers, i.e., planning research, applying fund, writing a paper and giving a talk in conferences. From interviews with students, we learn that such style of scientific activity is very effective in promoting student's motivation for learning science.

  9. RADAR Anechoic Chamber/RCS Measurements Lab

    Data.gov (United States)

    Federal Laboratory Consortium — The RF Anechoic Chamber is 56 feet long by 12 feet high by 13.5 feet wide, with an adjoining electronic computer control room. A double door entrance at one end of...

  10. High Performance Methane Thrust Chamber (HPMTC) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — ORBITEC proposes to develop a High-Performance Methane Thrust Chamber (HPMRE) to meet the demands of advanced chemical propulsion systems for deep-space mission...

  11. Resistive plate chambers for tomography and radiography

    National Research Council Canada - National Science Library

    C. Thomay; P. Baesso; D. Cussans; J. Davies; P. Glaysher; S. Quillin; S. Robertson; C. Steer; C. Vassallo; J. Velthuis

    2012-01-01

    Resistive Plate Chambers (RPCs) are widely used in high energy physics for both tracking and triggering purposes, due to their excellent time resolution, rate capability, and good spatial resolution...

  12. MAN-IN-SIMULANT TEST (MIST) CHAMBER

    Data.gov (United States)

    Federal Laboratory Consortium — The MIST chamber uses methyl salicylate (oil of wintergreen) vapor as a simulant for HD agent to conduct system level evaluations of chemical protective ensembles....

  13. Aeroacoustic sound generation in simple expansion chambers.

    Science.gov (United States)

    English, Emmet J; Holland, Keith R

    2010-11-01

    A method is presented for measuring the aeroacoustic source strength in ducts with flow at frequencies at which the wave motion can be considered substantially one-dimensional. The method is based on coherent power flux measurements using pairs of microphones positioned both upstream and downstream of the source region. The method is applied to a flow excited expansion chamber with aeroacoustic source measurements presented for chambers with a range of flow velocities and chamber lengths. The results indicate locked-on flow tones are generated in the chamber. The frequency of these locked-on flow tones is compared with that predicted using describing function theory applied to resonators with a grazing flow as well as that of other literature.

  14. Developing Cloud Chambers with High School Students

    Science.gov (United States)

    Ishizuka, Ryo; Tan, Nobuaki; Sato, Shoma; Zeze, Syoji

    The result and outcome of the cloud chamber project, which aims to develop a cloud chamber useful for science education is reported in detail. A project includes both three high school students and a teacher as a part of Super Science High School (SSH) program in our school. We develop a dry-ice-free cloud chamber using salt and ice (or snow). Technical details of the chamber are described. We also argue how the project have affected student's cognition, motivation, academic skills and behavior. The research project has taken steps of professional researchers, i.e., in planning research, applying fund, writing a paper and giving a talk in conferences. From interviews with students, we have learnt that such style of scientific activity is very effective in promoting student's motivation for learning science.

  15. Ceramic cutting tools materials, development and performance

    CERN Document Server

    Whitney, E Dow

    1994-01-01

    Interest in ceramics as a high speed cutting tool material is based primarily on favorable material properties. As a class of materials, ceramics possess high melting points, excellent hardness and good wear resistance. Unlike most metals, hardness levels in ceramics generally remain high at elevated temperatures which means that cutting tip integrity is relatively unaffected at high cutting speeds. Ceramics are also chemically inert against most workmetals.

  16. Emerging Ceramic-based Materials for Dentistry

    Science.gov (United States)

    Denry, I.; Kelly, J.R.

    2014-01-01

    Our goal is to give an overview of a selection of emerging ceramics and issues for dental or biomedical applications, with emphasis on specific challenges associated with full-contour zirconia ceramics, and a brief synopsis on new machinable glass-ceramics and ceramic-based interpenetrating phase composites. Selected fabrication techniques relevant to dental or biomedical applications such as microwave sintering, spark plasma sintering, and additive manufacturing are also reviewed. Where appropriate, the authors have added their opinions and guidance. PMID:25274751

  17. Micromechanical Evaluation of Ceramic Matrix Composites

    Science.gov (United States)

    1991-02-01

    Materials Sciences Corporation AD-A236 756 M.hM. 9 1 0513 IEIN HIfINU IIl- DTIC JUN 06 1991 MICROMECHANICAL EVALUATION OF S 0 CERAMIC MATRIX COMPOSITES C...Classification) \\() Micromechanical Evaluation of Ceramic Matrix Composites ) 12. PERSONAL AUTHOR(S) C-F. Yen, Z. Hashin, C. Laird, B.W. Rosen, Z. Wang 13a. TYPE...and strengthen the ceramic composites. In this task, various possibilities of crack propagation in unidirectional ceramic matrix composites under

  18. Micro powder injection molding——large scale production technology for micro-sized components

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Micro powder injection molding (μPIM),a miniaturized variant of powder injection molding,has advantages of shape complexity,applicability to many materials and good mechanical properties. Co-injection molding has been realized between met-als and ceramics on micro components,which become the first breakthrough within the PIM field. Combined with the prominent characteristics of high features/cost ratio,micro powder injection molding becomes a potential technique for large scale production of intricate and three-dimensional micro components or micro-structured components in microsystems technology (MST) field.

  19. Micro powder injection molding-large scale production technology for micro-sized components

    Institute of Scientific and Technical Information of China (English)

    YIN HaiQing; JIA ChengChang; QU XuanHui

    2008-01-01

    Micro powder injection molding (μPIM), a miniaturized variant of powder injection molding, has advantages of shape complexity, applicability to many materials and good mechanical properties. Co-injection molding has been realized between metals and ceramics on micro components, which become the first breakthrough within the PIM field. Combined with the prominent characteristics of high features/cost ratio, micro powder injection molding becomes a potential technique for large scale production of intricate and three-dimensional micro components or microstructured components in microsystems technology (MST) field.

  20. Effect of Chamber Backpressure on Swirl Injector Fluid Mechanics

    Science.gov (United States)

    Kenny, R. Jeremy; Hulka, James R.; Moser, Marlow D.; Rhys, Noah O.

    2008-01-01

    A common propellant combination used for high thrust generation is GH2/LOX. Historical GH2/LOX injection elements have been of the shear-coaxial type. Element type has a large heritage of research work to aid in element design. The swirl-coaxial element, despite its many performance benefits, has a relatively small amount of historical, LRE-oriented work to draw from. Design features of interest are grounded in the fluid mechanics of the liquid swirl process itself, are based on data from low-pressure, low mass flow rate experiments. There is a need to investigate how high ambient pressures and mass flow rates influence internal and external swirl features. The objective of this research is to determine influence of varying liquid mass flow rate and ambient chamber pressure on the intact-length fluid mechanics of a liquid swirl element.

  1. The Gargamelle heavy liquid bubble chamber

    CERN Multimedia

    1970-01-01

    This image shows the Gargamelle heavy liquid bubble chamber. It was used to detect particles in experiments at the PS between 1970 and 1976 before being moved to the SPS. In 1973, while working on the PS, it detected the first neutral current, an interaction vital to the electroweak theory. In 1978 a large fissure appeared in the body of the chamber and Gargamelle was stopped in 1979.

  2. The world's largest time projection chamber

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    Peter Glassel, the technical coordinator for the ALICE time projection chamber, is seen sitting inside the detector; the largest in the world at nearly 100 cubic metres. Thousands of wires are connected to read out electronic data produced as particles are created in lead-lead collisions at the centre of the detector. These particles will cause the medium within the time projection chamber to ionise along their tracks allowing the particle paths to be recreated.

  3. Electrostatic fields in an ionization chamber electret

    Science.gov (United States)

    Fallone, B. G.; Podgorsak, E. B.

    1983-09-01

    The theory of linear systems is used to derive the potential and electric field in distance space in a cylindrical polarization/depolarization electret chamber. General solutions for the near, intermediate, and far regions are given and their domains of convergence discussed. On the axis of the chamber the solutions for the electret surface are equal to those obtained from Gauss's and Kirchoff's laws, and at large distances from the surface to those obtained from the introduction of a dipole layer model.

  4. Tracking with wire chambers at high luminosities

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, G.G. (Indiana Univ., Bloomington, IN (USA) Stanford Linear Accelerator Center, Menlo Park, CA (USA))

    1989-12-01

    Radiation damage and rate limitations impose severe constraints on wire chambers at the SSC. Possible conceptual designs for wire chamber tracking systems that satisfy these constraints are discussed. Computer simulation studies of tracking in such systems are presented. Simulations of events from interesting physics at the SSC, including hits from minimum bias background events, are examined. Results of some preliminary pattern recognition studies are given. 11 refs., 10 figs.

  5. Detection of particles with a cloud chamber

    OpenAIRE

    Esteban Muñoz, Iván

    2016-01-01

    Cloud chambers were essential devices in early nuclear and particle physics research. Superseded by more modern detectors in actual research, they still remain very interesting pedagogical apparatus. This thesis attempts to give a global view on this topic. To do so, a review of the physical foundations of the diffusion cloud chamber, in which an alcohol is supersaturated by cooling it with a thermal reservoir, is carried out. Its main results are then applied to analyse the working con...

  6. The drift chambers of the NOMAD experiment

    Energy Technology Data Exchange (ETDEWEB)

    Anfreville, M.; Astier, P.; Authier, M.; Baldisseri, A.; Banner, M.; Besson, N.; Bouchez, J.; Castera, A.; Cloue, O.; Dumarchez, J. E-mail: jacques.dumarchez@cern.ch; Dumps, L.; Gangler, E.; Gosset, J.; Hagner, C.; Jollec, C.; Lachaud, C.; Letessier-Selvon, A.; Levy, J.-M.; Linssen, L.; Meyer, J.-P.; Ouriet, J.-P.; Passerieux, J.-P.; Margaley, T.P.T. Pedrol; Placci, A.; Pluquet, A.; Poinsignon, J.; Popov, B.A.; Rathouit, P.; Schahmaneche, K.; Stolarczyk, T.; Uros, V.; Vannucci, F.; Vo, M.K.; Zaccone, H

    2002-04-01

    We present a detailed description of the drift chambers used as an active target and a tracking device in the NOMAD experiment at CERN. The main characteristics of these chambers are a large area (3{center_dot}3 m{sup 2}), a self-supporting structure made of light composite materials and a low cost. A spatial resolution of 150 {mu}m has been achieved with a single hit efficiency of 97%.

  7. Beam injection into RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, W.; Hahn, H.; MacKay, W.W.; Satogata, T.; Tsoupas, N.; Zhang, W.

    1997-07-01

    During the RHIC sextant test in January 1997 beam was injected into a sixth of one of the rings for the first time. The authors describe the injection zone and its bottlenecks. They report on the commissioning of the injection system, on beam based measurements of the kickers and the application program to steer the beam.

  8. Injection moulding antireflective nanostructures

    DEFF Research Database (Denmark)

    Christiansen, Alexander Bruun; Clausen, Jeppe Sandvik; Mortensen, N. Asger

    2014-01-01

    in an injection moulding process, to fabricate the antireflective surfaces. The cycle-time was 35 s. The injection moulded structures had a height of 125 nm, and the visible spectrum reflectance of injection moulded black polypropylene surfaces was reduced from 4.5±0.5% to 2.5±0.5%. The gradient of the refractive...

  9. Injection moulding antireflective nanostructures

    DEFF Research Database (Denmark)

    Christiansen, Alexander Bruun; Clausen, Jeppe Sandvik; Mortensen, N. Asger

    in an injection moulding process, to fabricate the antireflective surfaces. The cycle-time was 35 s. The injection moulded structures had a height of 125 nm, and the visible spectrum reflectance of injection moulded black polypropylene surfaces was reduced from 4.5±0.5% to 2.5±0.5%. The gradient of the refractive...

  10. Durability of feldspathic veneering ceramic on glass-infiltrated alumina ceramics after long-term thermocycling.

    Science.gov (United States)

    Mesquita, A M M; Ozcan, M; Souza, R O A; Kojima, A N; Nishioka, R S; Kimpara, E T; Bottino, M A

    2010-01-01

    This study compared the bond strength durability of a feldspathic veneering ceramic to glass-infiltrated reinforced ceramics in dry and aged conditions. Disc shaped (thickness: 4 mm, diameter: 4 mm) of glass-infiltrated alumina (In-Ceram Alumina) and glass-infiltrated alumina reinforced by zirconia (In-Ceram Zirconia) core ceramic specimens (N=48, N=12 per groups) were constructed according to the manufacturers' recommendations. Veneering ceramic (VITA VM7) was fired onto the core ceramics using a mold. The core-veneering ceramic assemblies were randomly divided into two conditions and tested either immediately after specimen preparation (Dry) or following 30000 thermocycling (5-55 ºC±1; dwell time: 30 seconds). Shear bond strength test was performed in a universal testing machine (cross-head speed: 1 mm/min). Failure modes were analyzed using optical microscope (x20). The bond strength data (MPa) were analyzed using ANOVA (α=0.05). Thermocycling did not decrease the bond strength results for both In-Ceram Alumina (30.6±8.2 MPa; P=0.2053) and In-Ceram zirconia (32.6±9 MPa; P=0.3987) core ceramic-feldspathic veneering ceramic combinations when compared to non-aged conditions (28.1±6.4 MPa, 29.7±7.3 MPa, respectively). There were also no significant differences between adhesion of the veneering ceramic to either In-Ceram Alumina or In-Ceram Zirconia ceramics (P=0.3289). Failure types were predominantly a mixture of adhesive failure between the veneering and the core ceramic together with cohesive fracture of the veneering ceramic. Long-term thermocycling aging conditions did not impair the adhesion of the veneering ceramic to the glass-infiltrated alumina core ceramics tested.

  11. Influence of immunization on Porphyromonas gingivalis colonization and invasion in the mouse chamber model.

    Science.gov (United States)

    Genco, C A; Kapczynski, D R; Cutler, C W; Arko, R J; Arnold, R R

    1992-01-01

    The effects of immunization with invasive or noninvasive Porphyromonas (Bacteroides) gingivalis strains on the pathogenesis of infection in a mouse chamber model were examined. BALB/c mice were immunized by a single injection of heat-killed P. gingivalis invasive strain A7436 or W83 or noninvasive strain 33277, HG405, or 381 directly into subcutaneous chambers. P. gingivalis-specific antibody was detected in chamber fluid 21 days postimmunization, and mice were subsequently challenged by injection of exponential-phase P. gingivalis into chambers. Immunization with A7436 or W83 followed by challenge with A7436 protected mice against secondary abscess formation and death; however, P. gingivalis persisted in chambers for up to 14 days postchallenge. Immunization with noninvasive strain 33277, HG405, or 381 followed by challenge with invasive strain A7436 or W83 protected mice against secondary lesion formation and death. P. gingivalis was cultured from 33277- or HG405-immunized and nonimmunized animals to day 14. All P. gingivalis strains induced an immunoglobulin G response, as measured by an enzyme-linked immunosorbent assay and Western immunoblotting of P. gingivalis whole-cell and outer membrane protein preparations. Western blot analyses indicated that sera from mice immunized with different invasive and noninvasive strains recognized common P. gingivalis antigens. In summary, immunization with invasive P. gingivalis A7436 and W83 or noninvasive P. gingivalis 33277, HG405, and 381 protected mice from secondary lesion formation and death after challenge with invasive P. gingivalis A7436 or W83. P. gingivalis-specific antibody did not, however, inhibit the colonization of P. gingivalis within chambers. Images PMID:1312515

  12. In vitro penetration of bleaching agents into the pulp chamber

    DEFF Research Database (Denmark)

    Benetti, Ana Raquel; Valera, M C; Mancini, M N G

    2004-01-01

    To investigate pulp chamber penetration of bleaching agents in teeth following restorative procedures.......To investigate pulp chamber penetration of bleaching agents in teeth following restorative procedures....

  13. Chamber for Growing and Observing Fungi

    Science.gov (United States)

    Pierson, Duane L.; Molina, Thomas C.

    2005-01-01

    A chamber has been designed to enable growth and observation of microcolonies of fungi in isolation from the external environment. Unlike prior fungus-growing apparatuses, this chamber makes it possible to examine a fungus culture without disrupting it. Partly resembling a small picture frame, the chamber includes a metal plate having a rectangular through-thethickness opening with recesses for a top and a bottom cover glass, an inlet for air, and an inlet for water. The bottom cover glass is put in place and held there by clips, then a block of nutrient medium and a moisture pad are placed in the opening. The block is inoculated, then the top cover glass is put in place and held there by clips. Once growth is evident, the chamber can be sealed with tape. Little (if any) water evaporates past the edges of the cover glasses, and, hence there is little (if any) need to add water. A microscope can be used to observe the culture through either cover glass. Because the culture is sealed in the chamber, it is safe to examine the culture without risking contamination. The chamber can be sterilized and reused.

  14. The GODDESS ionization chamber: developing robust windows

    Science.gov (United States)

    Blanchard, Rose; Baugher, Travis; Cizewski, Jolie; Pain, Steven; Ratkiewicz, Andrew; Goddess Collaboration

    2015-10-01

    Reaction studies of nuclei far from stability require high-efficiency arrays of detectors and the ability to identify beam-like particles, especially when the beam is a cocktail beam. The Gammasphere ORRUBA Dual Detectors for Experimental Structure Studies (GODDESS) is made up of the Oak Ridge-Rutgers University Barrel Array (ORRUBA) of silicon detectors for charged particles inside of the gamma-ray detector array Gammasphere. A high-rate ionization chamber is being developed to identify beam-like particles. Consisting of twenty-one alternating anode and cathode grids, the ionization chamber sits downstream of the target chamber and is used to measure the energy loss of recoiling ions. A critical component of the system is a thin and robust mylar window which serves to separate the gas-filled ionization chamber from the vacuum of the target chamber with minimal energy loss. After construction, windows were tested to assure that they would not break below the required pressure, causing harm to the wire grids. This presentation will summarize the status of the ionization chamber and the results of the first tests with beams. This work is supported in part by the U.S. Department of Energy and National Science Foundation.

  15. Expandable Purge Chambers Would Protect Cryogenic Fittings

    Science.gov (United States)

    Townsend, Ivan I., III

    2004-01-01

    Expandable ice-prevention and cleanliness-preservation (EIP-CP) chambers have been proposed to prevent the accumulation of ice or airborne particles on quick-disconnect (QD) fittings, or on ducts or tubes that contain cryogenic fluids. In the original application for which the EIP-CP chambers were conceived, there is a requirement to be able to disconnect and reconnect the QD fittings in rapid succession. If ice were to form on the fittings by condensation and freezing of airborne water vapor on the cold fitting surfaces, the ice could interfere with proper mating of the fittings, making it necessary to wait an unacceptably long time for the ice to thaw before attempting reconnection. By keeping water vapor away from the cold fitting surfaces, the EIP-CP chambers would prevent accumulation of ice, preserving the ability to reconnect as soon as required. Basically, the role of an EIP-CP chamber would be to serve as an enclosure for a flow of dry nitrogen gas that would keep ambient air away from QD cryogenic fittings. An EIP-CP chamber would be an inflatable device made of a fabriclike material. The chamber would be attached to an umbilical plate holding a cryogenic QD fitting.

  16. Laser peripheral iridotomy changes anterior chamber architecture.

    Science.gov (United States)

    Theinert, Christian; Wiedemann, Peter; Unterlauft, Jan D

    2017-01-19

    The pressure gradient between anterior and posterior chamber in acute angle closure (AAC) and primary angle closure suspects is balanced by a sufficient laser peripheral iridotomy (LPI). The anterior chamber changes induced by LPI in patients with unilateral AAC were examined and compared to healthy eyes to define threshold values, which may help to discriminate between healthy and diseased eyes. Using Scheimpflug photography, anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), and central corneal thickness (CCT) were measured before and after LPI in both eyes of unilateral AAC cases. These measurements were compared to a group of healthy control eyes to determine threshold values for ACD, ACV, and ACA. The ACD, ACV, and ACA increased significantly in the 25 AAC eyes after LPI. The ACD, ACV, ACA, and CCT values in the AAC eyes obtained before LPI were compared to a control group of 59 healthy eyes with wide open chamber angles. The cutoff values revealed by receiver operating characteristic analysis were 2.1 mm for ACD, 90.5 mm2 for ACV, and 27.25° for ACA. Our results confirm the significant changes of the anterior segments architecture induced by LPI in AAC eyes. The found threshold values for ACD, ACV, and ACA may help in daily clinical routine to discriminate between healthy eyes and those in need for a prophylactic LPI.

  17. Temperature Studies for ATLAS MDT BOS Chambers

    CERN Document Server

    Engl, A; Hertenberger, R; Mameghani, R; Merkl, D; Rauscher, F; Schaile, A D; Ströhmer, R

    2009-01-01

    Data sets with high statistics taken at the cosmic ray facility, equipped with 3 ATLAS BOS MDT chambers, in Garching (Munich) have been used to study temperature and pressure effects on gas gain and drifttime. The deformation of a thermally expanded chamber was reconstructed using the internal RasNik alignment monitoring system and the tracks from cosmic data. For these studies a heating system was designed to increase the temperature of the middle chamber by up to 20 Kelvins over room temperature. For comparison the temperature effects on gas properties have been simulated with Garfield. The maximum drifttime decreased under temperature raise by -2.21 +- 0.08 ns/K, in agreement with the results of pressure variations and the Garfield simulation. The increased temperatures led to a linear increase of the gas gain of about 2.1% 1/K. The chamber deformation has been analyzed with the help of reconstructed tracks. By the comparison of the tracks through the reference chambers with these through the test chamber ...

  18. Patches for Repairing Ceramics and Ceramic-Matrix Composites

    Science.gov (United States)

    Hogenson, Peter A.; Toombs, Gordon R.; Adam, Steven; Tompkins, James V.

    2006-01-01

    Patches consisting mostly of ceramic fabrics impregnated with partially cured polymers and ceramic particles are being developed as means of repairing ceramics and ceramic-matrix composites (CMCs) that must withstand temperatures above the melting points of refractory metal alloys. These patches were conceived for use by space-suited, space-walking astronauts in repairing damaged space-shuttle leading edges: as such, these patches could be applied in the field, in relatively simple procedures, and with minimal requirements for specialized tools. These design characteristics also make the patches useful for repairing ceramics and CMCs in terrestrial settings. In a typical patch as supplied to an astronaut or repair technician, the polymer would be in a tacky condition, denoted as an A stage, produced by partial polymerization of a monomeric liquid. The patch would be pressed against the ceramic or CMC object to be repaired, relying on the tackiness for temporary adhesion. The patch would then be bonded to the workpiece and cured by using a portable device to heat the polymer to a curing temperature above ambient temperature but well below the maximum operating temperature to which the workpiece is expected to be exposed. The patch would subsequently become pyrolized to a ceramic/glass condition upon initial exposure to the high operating temperature. In the original space-shuttle application, this exposure would be Earth-atmosphere-reentry heating to about 3,000 F (about 1,600 C). Patch formulations for space-shuttle applications include SiC and ZrO2 fabrics, a commercial SiC-based pre-ceramic polymer, and suitable proportions of both SiC and ZrO2 particles having sizes of the order of 1 m. These formulations have been tailored for the space-shuttle leading-edge material, atmospheric composition, and reentry temperature profile so as to enable repairs to survive re-entry heating with expected margin. Other formulations could be tailored for specific terrestrial

  19. Ceramics and ceramic matrix composites - Aerospace potential and status

    Science.gov (United States)

    Levine, Stanley R.

    1992-01-01

    Thermostructural ceramics and ceramic-matrix composites are attractive in numerous aerospace applications; the noncatastrophic fracture behavior and flaw-insensitivity of continuous fiber-reinforced CMCs renders them especially desirable. The present development status evaluation notes that, for most highly-loaded high-temperature applications, the requisite fiber-technology base is at present insufficient. In addition to materials processing techniques, the life prediction and NDE methods are immature and require a projection of 15-20 years for the maturity of CMC turbine rotors. More lightly loaded, moderate temperature aircraft engine applications are approaching maturity.

  20. Dense high temperature ceramic oxide superconductors

    Science.gov (United States)

    Landingham, Richard L.

    1993-01-01

    Dense superconducting ceramic oxide articles of manufacture and methods for producing these articles are described. Generally these articles are produced by first processing these superconducting oxides by ceramic processing techniques to optimize materials properties, followed by reestablishing the superconducting state in a desired portion of the ceramic oxide composite.