Vacuum-isolation vessel and method for measurement of thermal noise in microphones
NASA Technical Reports Server (NTRS)
Zuckerwar, Allan J. (Inventor); Ngo, Kim Chi T. (Inventor)
1992-01-01
The vacuum isolation vessel and method in accordance with the present invention are used to accurately measure thermal noise in microphones. The apparatus and method could be used in a microphone calibration facility or any facility used for testing microphones. Thermal noise is measured to determine the minimum detectable sound pressure by the microphone. Conventional isolation apparatus and methods have been unable to provide an acoustically quiet and substantially vibration free environment for accurately measuring thermal noise. In the present invention, an isolation vessel assembly comprises a vacuum sealed outer vessel, a vacuum sealed inner vessel, and an interior suspension assembly coupled between the outer and inner vessels for suspending the inner vessel within the outer vessel. A noise measurement system records thermal noise data from the isolation vessel assembly. A vacuum system creates a vacuum between an internal surface of the outer vessel and an external surface of the inner vessel. The present invention thus provides an acoustically quiet environment due to the vacuum created between the inner and outer vessels and a substantially vibration free environment due to the suspension assembly suspending the inner vessel within the outer vessel. The thermal noise in the microphone, effectively isolated according to the invention, can be accurately measured.
Ejector/liquid ring pump provides <0. 30 mm Hg vacuum for polymerization vessel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lockwood, A.; Gaines, A.
1982-03-01
Firestone Fibers and Textiles Company, a division of Firestone Tire and Rubber Company, manufactures tire and industrial yarns of polyester and nylon-6. Nylon-6 molding and extrusion resins are also produced at the plant in Hopewell, Virginia. The process for making polyester requires an extremely low vacuum on the polymerization reactor. A consistent polymerization vessel vacuum of 0.3 mm Hg is needed, but the existing vacuum source, a five-stage steam jet ejector, could only provide a 0.5 mm Hg level. Two options were considered when the company decided to replace the original system with a system designed for 0.15 mm Hgmore » with a non-condensible gas load of 10.8 lb/hr. A new five-stage jet ejector system to meet these requirements would use 1395 lb/hr of 100 psig steam. The other option was a hybrid vacuum source composed of a three-stage steam ejector system and a liquid ring vacuum pump that is more energy efficient than ejectors for low vacuum applications. The hybrid system was selected because the three-stage jet ejector would use only 1240 lb/hr of 100 psig steam. The liquid ring vacuum pump would increase the material and installation cost of the system by about $4000, but the savings in steam consumption would pay back the added cost in less than two years. The jet ejector/liquid ring vacuum pump system has provided both the capacity and the extremely low vacuum needed for the polyester polymerization vessel, after making a small modification. The hybrid vacuum source is reliable, requires only routine maintenance, and will contiue to save substantial amounts of steam each year compared to the five-stage steam jet ejector.« less
New baking system for the RFX vacuum vessel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Collarin, P.; Luchetta, A.; Sonato, P.
A heating system based on eddy currents has been developed for the vacuum vessel of the RFX Reversed Field Pinch device. After a testing phase, carried out at low power, the final power supply system has been designed and installed. It has been used during last year to bake out the vessel and the graphite first wall up to 320{degree}C. Recently the heating system has been completed with a control system that allows for baking sessions with an automatic control of the vacuum vessel temperature and for pulse sessions with a heated first wall. After the description of the preliminarymore » analyses and tests, and of the main characteristics of the power supply and control systems, the experimental results of the baking sessions performed during last year are presented. 6 refs., 7 figs.« less
NASA Astrophysics Data System (ADS)
Maheshwari, A.; Pathak, H. A.; Mehta, B. K.; Phull, G. S.; Laad, R.; Shaikh, M. S.; George, S.; Joshi, K.; Khan, Z.
2017-04-01
ITER Vacuum Vessel is a torus-shaped, double wall structure. The space between the double walls of the VV is filled with In-Wall Shielding Blocks (IWS) and Water. The main purpose of IWS is to provide neutron shielding during ITER plasma operation and to reduce ripple of Toroidal Magnetic Field (TF). Although In-Wall Shield Blocks (IWS) will be submerged in water in between the walls of the ITER Vacuum Vessel (VV), Outgassing Rate (OGR) of IWS materials plays a significant role in leak detection of Vacuum Vessel of ITER. Thermal Outgassing Rate of a material critically depends on the Surface Roughness of material. During leak detection process using RGA equipped Leak detector and tracer gas Helium, there will be a spill over of mass 3 and mass 2 to mass 4 which creates a background reading. Helium background will have contribution of Hydrogen too. So it is necessary to ensure the low OGR of Hydrogen. To achieve an effective leak test it is required to obtain a background below 1 × 10-8 mbar 1 s-1 and hence the maximum Outgassing rate of IWS Materials should comply with the maximum Outgassing rate required for hydrogen i.e. 1 x 10-10 mbar 1 s-1 cm-2 at room temperature. As IWS Materials are special materials developed for ITER project, it is necessary to ensure the compliance of Outgassing rate with the requirement. There is a possibility of diffusing the gasses in material at the time of production. So, to validate the production process of materials as well as manufacturing of final product from this material, three coupons of each IWS material have been manufactured with the same technique which is being used in manufacturing of IWS blocks. Manufacturing records of these coupons have been approved by ITER-IO (International Organization). Outgassing rates of these coupons have been measured at room temperature and found in acceptable limit to obtain the required Helium Background. On the basis of these measurements, test reports have been generated and got
NASA Astrophysics Data System (ADS)
Kumar, B. Ramesh; Gangradey, R.
2012-11-01
Advanced fusion reactors like ITER and up coming Indian DEMO devices are having challenges in terms of their materials design and fabrication procedures. The operation of these devices is having various loads like structural, thermo-mechanical and neutron irradiation effects on major systems like vacuum vessel, divertor, magnets and blanket modules. The concept of double wall vacuum vessel (VV) is proposed in view of protecting of major reactor subsystems like super conducting magnets, diagnostic systems and other critical components from high energy 14 MeV neutrons generated from fusion plasma produced by D-T reactions. The double walled vacuum vessel is used in combination with pressurized water circulation and some special grade borated steel blocks to shield these high energy neutrons effectively. The fabrication of sub components in VV are mainly used with high thickness SS materials in range of 20 mm- 60 mm of various grades based on the required protocols. The structural components of double wall vacuum vessel uses various parts like shields, ribs, shells and diagnostic vacuum ports. These components are to be developed with various welding techniques like TIG welding, Narrow gap TIG welding, Laser welding, Hybrid TIG laser welding, Electron beam welding based on requirement. In the present paper the samples of 20 mm and 40 mm thick SS 316 materials are developed with TIG welding process and their mechanical properties characterization with Tensile, Bend tests and Impact tests are carried out. In addition Vickers hardness tests and microstructural properties of Base metal, Heat Affected Zone (HAZ) and Weld Zone are done. TIG welding application with high thick SS materials in connection with vacuum vessel requirements and involved criticalities towards welding process are highlighted.
General and crevice corrosion study of the in-wall shielding materials for ITER vacuum vessel
NASA Astrophysics Data System (ADS)
Joshi, K. S.; Pathak, H. A.; Dayal, R. K.; Bafna, V. K.; Kimihiro, Ioki; Barabash, V.
2012-11-01
Vacuum vessel In-Wall Shield (IWS) will be inserted between the inner and outer shells of the ITER vacuum vessel. The behaviour of IWS in the vacuum vessel especially concerning the susceptibility to crevice of shielding block assemblies could cause rapid and extensive corrosion attacks. Even galvanic corrosion may be due to different metals in same electrolyte. IWS blocks are not accessible until life of the machine after closing of vacuum vessel. Hence, it is necessary to study the susceptibility of IWS materials to general corrosion and crevice corrosion under operations of ITER vacuum vessel. Corrosion properties of IWS materials were studied by using (i) Immersion technique and (ii) Electro-chemical Polarization techniques. All the sample materials were subjected to a series of examinations before and after immersion test, like Loss/Gain weight measurement, SEM analysis, and Optical stereo microscopy, measurement of surface profile and hardness of materials. After immersion test, SS 304B4 and SS 304B7 showed slight weight gain which indicate oxide layer formation on the surface of coupons. The SS 430 material showed negligible weight loss which indicates mild general corrosion effect. On visual observation with SEM and Metallography, all material showed pitting corrosion attack. All sample materials were subjected to series of measurements like Open Circuit potential, Cyclic polarization, Pitting potential, protection potential, Critical anodic current and SEM examination. All materials show pitting loop in OC2 operating condition. However, its absence in OC1 operating condition clearly indicates the activity of chloride ion to penetrate oxide layer on the sample surface, at higher temperature. The critical pitting temperature of all samples remains between 100° and 200°C.
Electrical insulation system for the shell-vacuum vessel and poloidal field gap in the ZTH machine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reass, W.A.; Ballard, E.O.
1989-01-01
The electrical insulation systems for the ZTH machine have many unusual design problems. The poloidal field gap insulation must be capable of conforming to poloidal and toroidal contours, provide a 25 kV hold off, and sufficiently adhere to the epoxy back fill between the overlapping conductors. The shell-vacuum vessel system will use stretchable and flexible insulation along with protective hats, boots and sleeves. The shell-vacuum vessel system must be able to withstand a 12.5 kV pulse with provision for thermal insulation to limit the effects of the 300{degrees}C vacuum vessel during operation and bakeout. Methodology required to provide the electricalmore » protection along with testing data and material characteristics will be presented. 7 figs.« less
Optimization of a vacuum chamber for vibration measurements.
Danyluk, Mike; Dhingra, Anoop
2011-10-01
A 200 °C high vacuum chamber has been built to improve vibration measurement sensitivity. The optimized design addresses two significant issues: (i) vibration measurements under high vacuum conditions and (ii) use of design optimization tools to reduce operating costs. A test rig consisting of a cylindrical vessel with one access port has been constructed with a welded-bellows assembly used to seal the vessel and enable vibration measurements in high vacuum that are comparable with measurements in air. The welded-bellows assembly provides a force transmissibility of 0.1 or better at 15 Hz excitation under high vacuum conditions. Numerical results based on design optimization of a larger diameter chamber are presented. The general constraints on the new design include material yield stress, chamber first natural frequency, vibration isolation performance, and forced convection heat transfer capabilities over the exterior of the vessel access ports. Operating costs of the new chamber are reduced by 50% compared to a preexisting chamber of similar size and function.
Design of a dee vacuum vessel for Doublet III
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, L.G.
1983-04-01
The Doublet III tokamak is to be modified wherein the original 'doublet' plasma containment vacuum vessel will be exchanged with one of a large dee-shaped cross section. The basic dimensions of the dee vessel will allow plasmas of 1.7-m major radius, 0.7-m minor radius, and a vertical elongation of 1.8. Installation of a large dee vessel in Doublet III is made possible by the demountable toroidal field coils and the large, low-ripple volume they include. Ripple at the plasma edge will be less than one percent. The plasma parameters affecting the design of the vessel will be reviewed including plasmamore » current, power, disruption time, allowable error field, impurity control techniques, pulse length, and limiter schemes. A driving requirement for the design of the vessel is to maximize the access to the plasma for auxiliary heating (both neutral beam injection and radio frequency heating), diagnostics, developmental component and material testing, and pumping. The dee vessel is structurally designed along the same lines as the present vessel: an Inconel 625, all-welded, continuous chamber in a corrugated sandwich construction. An overview of the vessel design and its solutions to the design criteria will be presented. An overview will also be presented of the entire modification project which includes replacement of some coils, and addition of support structure, limiters and vessel armor, and power system components.« less
Measurement of eddy-current distribution in the vacuum vessel of the Sino-UNIted Spherical Tokamak.
Li, G; Tan, Y; Liu, Y Q
2015-08-01
Eddy currents have an important effect on tokamak plasma equilibrium and control of magneto hydrodynamic activity. The vacuum vessel of the Sino-UNIted Spherical Tokamak is separated into two hemispherical sections by a toroidal insulating barrier. Consequently, the characteristics of eddy currents are more complex than those found in a standard tokamak. Thus, it is necessary to measure and analyze the eddy-current distribution. In this study, we propose an experimental method for measuring the eddy-current distribution in a vacuum vessel. By placing a flexible printed circuit board with magnetic probes onto the external surface of the vacuum vessel to measure the magnetic field parallel to the surface and then subtracting the magnetic field generated by the vertical-field coils, the magnetic field due to the eddy current can be obtained, and its distribution can be determined. We successfully applied this method to the Sino-UNIted Spherical Tokamak, and thus, we obtained the eddy-current distribution despite the presence of the magnetic field generated by the external coils.
NASTRAN analysis of Tokamak vacuum vessel using interactive graphics
NASA Technical Reports Server (NTRS)
Miller, A.; Badrian, M.
1978-01-01
Isoparametric quadrilateral and triangular elements were used to represent the vacuum vessel shell structure. For toroidally symmetric loadings, MPCs were employed across model boundaries and rigid format 24 was invoked. Nonsymmetric loadings required the use of the cyclic symmetry analysis available with rigid format 49. NASTRAN served as an important analysis tool in the Tokamak design effort by providing a reliable means for assessing structural integrity. Interactive graphics were employed in the finite element model generation and in the post-processing of results. It was felt that model generation and checkout with interactive graphics reduced the modelling effort and debugging man-hours significantly.
Calculation of Eddy Currents In the CTH Vacuum Vessel and Coil Frame
DOE Office of Scientific and Technical Information (OSTI.GOV)
A. Zolfaghari, A. Brooks, A. Michaels, J. Hanson, and G. Hartwell
2012-09-25
Knowledge of eddy currents in the vacuum vessel walls and nearby conducting support structures can significantly contribute to the accuracy of Magnetohydrodynamics (MHD) equilibrium reconstruction in toroidal plasmas. Moreover, the magnetic fields produced by the eddy currents could generate error fields that may give rise to islands at rational surfaces or cause field lines to become chaotic. In the Compact Toroidal Hybrid (CTH) device (R0 = 0.75 m, a = 0.29 m, B ≤ 0.7 T), the primary driver of the eddy currents during the plasma discharge is the changing flux of the ohmic heating transformer. Electromagnetic simulations are usedmore » to calculate eddy current paths and profile in the vacuum vessel and in the coil frame pieces with known time dependent currents in the ohmic heating coils. MAXWELL and SPARK codes were used for the Electromagnetic modeling and simulation. MAXWELL code was used for detailed 3D finite-element analysis of the eddy currents in the structures. SPARK code was used to calculate the eddy currents in the structures as modeled with shell/surface elements, with each element representing a current loop. In both cases current filaments representing the eddy currents were prepared for input into VMEC code for MHD equilibrium reconstruction of the plasma discharge. __________________________________________________« less
Very-Low-Cost, Rugged Vacuum System
NASA Technical Reports Server (NTRS)
Kline-Schoder, Robert; Sorensen, Paul; Passow, Christian; Bilski, Steve
2013-01-01
NASA, DoD, DHS, and commercial industry have a need for miniaturized, rugged, low-cost vacuum systems. Recent advances in sensor technology have led to the development of very small mass spectrometer detectors as well as other miniature analytical instruments. However, the vacuum systems to support these sensors remain large, heavy, and power-hungry. To meet this need, a miniaturized vacuum system was created based on a very small, rugged, and inexpensive- to-manufacture molecular drag pump (MDP). The MDP is enabled by the development of a miniature, veryhigh- speed, rugged, low-power, brushless DC motor optimized for wide temperature operation and long life. Such a pump represents an order-of-magnitude reduction in mass, volume, and cost over current, commercially available, state-ofthe- art vacuum pumps. The vacuum system consists of the MDP coupled to a ruggedized rough pump (for terrestrial applications or for planets with substantial atmospheres). The rotor in the MDP consists of a simple smooth cylinder of aluminum spinning at approximately 200,000 RPM inside an outer stator housing. The pump stator comprises a cylindrical aluminum housing with one or more specially designed grooves that serve as flow channels. To minimize the length of the pump, the gas is forced down the flow channels of the outer stator to the base of the pump. The gas is then turned and pulled toward the top through a second set of channels cut into an inner stator housing that surrounds the motor. The compressed gas then flows down channels in the motor housing to the exhaust port of the pump. The exhaust port of the pump is connected to a diaphragm or scroll pump. This pump delivers very high performance in a very small envelope. The design was simplified so that a smaller compression ratio, easier manufacturing process, and enhanced ruggedness can be achieved at the lowest possible cost. The machining of the rotor and stators is very simple compared to that necessary to fabricate TMP
Protective interior wall and attach8ing means for a fusion reactor vacuum vessel
Phelps, Richard D.; Upham, Gerald A.; Anderson, Paul M.
1988-01-01
An array of connected plates mounted on the inside wall of the vacuum vessel of a magnetic confinement reactor in order to provide a protective surface for energy deposition inside the vessel. All fasteners are concealed and protected beneath the plates, while the plates themselves share common mounting points. The entire array is installed with torqued nuts on threaded studs; provision also exists for thermal expansion by mounting each plate with two of its four mounts captured in an oversize grooved spool. A spool-washer mounting hardware allows one edge of a protective plate to be torqued while the other side remains loose, by simply inverting the spool-washer hardware.
Buckling analysis of Big Dee Vacuum Vessel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lightner, S.; Gallix, R.
1983-12-01
A simplified three-dimensional shell buckling analysis of the GA Technologies Inc., Big Dee Vacuum Vessel (V/V) was performed using the finite element program TRICO. A coarse-mesh linear elastic model, which accommodated the support boundary conditions, was used to determine the buckling mode shape under a uniform external pressure. Using this buckling mode shape, refined models were used to calculate the linear buckling load (P/sub crit/) more accurately. Several different designs of the Big Dee V/V were considered in this analysis. The supports for the V/V were equally-spaced radial pins at the outer diameter of the mid-plane. For all the casesmore » considered, the buckling mode was axisymmetric in the toroidal direction. Therefore, it was possible to use only a small angular sector of a toric shell for the refined analysis. P/sub crit/ for the Big Dee is about 60 atm for a uniform external pressure. Also investigated in this analysis were the effects of geometrical imperfections and non-uniform pressure distributions.« less
Low-Cost, Rugged High-Vacuum System
NASA Technical Reports Server (NTRS)
Sorensen, Paul; Kline-Schoder, Robert
2012-01-01
A need exists for miniaturized, rugged, low-cost high-vacuum systems. Recent advances in sensor technology have led to the development of very small mass spectrometer detectors as well as other analytical instruments such as scanning electron microscopes. However, the vacuum systems to support these sensors remain large, heavy, and power-hungry. To meet this need, a miniaturized vacuum system was developed based on a very small, rugged, and inexpensive-to-manufacture molecular drag pump (MDP). The MDP is enabled by a miniature, very-high-speed (200,000 rpm), rugged, low-power, brushless DC motor optimized for wide temperature operation and long life. The key advantages of the pump are reduced cost and improved ruggedness compared to other mechanical hig-hvacuum pumps. The machining of the rotor and stators is very simple compared to that necessary to fabricate rotor and stator blades for other pump designs. Also, the symmetry of the rotor is such that dynamic balancing of the rotor will likely not be necessary. Finally, the number of parts in the unit is cut by nearly a factor of three over competing designs. The new pump forms the heart of a complete vacuum system optimized to support analytical instruments in terrestrial applications and on spacecraft and planetary landers. The MDP achieves high vacuum coupled to a ruggedized diaphragm rough pump. Instead of the relatively complicated rotor and stator blades used in turbomolecular pumps, the rotor in the MDP consists of a simple, smooth cylinder of aluminum. This will turn at approximately 200,000 rpm inside an outer stator housing. The pump stator comprises a cylindrical aluminum housing with one or more specially designed grooves that serve as flow channels. To minimize the length of the pump, the gas is forced down the flow channels of the outer stator to the base of the pump. The gas is then turned and pulled toward the top through a second set of channels cut into an inner stator housing that surrounds the
Progress and achievements of R&D activities for the ITER vacuum vessel
NASA Astrophysics Data System (ADS)
Nakahira, M.; Takahashi, H.; Koizumi, K.; Onozuka, M.; Ioki, K.
2001-04-01
The Full Scale Sector Model Project, which was initiated in 1995 as one of the Seven Large Projects for ITER R&D, has been continued with the joint effort of the ITER Joint Central Team and the Japanese, Russian Federation and United States Home Teams. The fabrication of a full scale 18° toroidal sector, which is composed of two 9° sectors spliced at the port centre, was successfully completed in September 1997 with a dimensional accuracy of +/-3 mm for the total height and total width. Both sectors were shipped to the test site at the Japan Atomic Energy Research Institute and the integration test of the sectors was begun in October 1997. The integration test involves the adjustment of field joints, automatic narrow gap tungsten inert gas welding of field joints with splice plates and inspection of the joints by ultrasonic testing, as required for the initial assembly of the ITER vacuum vessel. This first demonstration of field joint welding and the performance test of the mechanical characteristics were completed in May 1998, and all the results obtained have satisfied the ITER design. In addition to these tests, integration with the midplane port extension fabricated by the Russian Home Team by using a fully remotized welding and cutting system developed by the US Home Team was completed in March 2000. The article describes the progress, achievements and latest status of the R&D activities for the ITER vacuum vessel.
THERMAL DESIGN OF THE ITER VACUUM VESSEL COOLING SYSTEM
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carbajo, Juan J; Yoder Jr, Graydon L; Kim, Seokho H
RELAP5-3D models of the ITER Vacuum Vessel (VV) Primary Heat Transfer System (PHTS) have been developed. The design of the cooling system is described in detail, and RELAP5 results are presented. Two parallel pump/heat exchanger trains comprise the design one train is for full-power operation and the other is for emergency operation or operation at decay heat levels. All the components are located inside the Tokamak building (a significant change from the original configurations). The results presented include operation at full power, decay heat operation, and baking operation. The RELAP5-3D results confirm that the design can operate satisfactorily during bothmore » normal pulsed power operation and decay heat operation. All the temperatures in the coolant and in the different system components are maintained within acceptable operating limits.« less
Development of advanced manufacturing technologies for low cost hydrogen storage vessels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leavitt, Mark; Lam, Patrick
2014-12-29
The U.S. Department of Energy (DOE) defined a need for low-cost gaseous hydrogen storage vessels at 700 bar to support cost goals aimed at 500,000 units per year. Existing filament winding processes produce a pressure vessel that is structurally inefficient, requiring more carbon fiber for manufacturing reasons, than would otherwise be necessary. Carbon fiber is the greatest cost driver in building a hydrogen pressure vessel. The objective of this project is to develop new methods for manufacturing Type IV pressure vessels for hydrogen storage with the purpose of lowering the overall product cost through an innovative hybrid process of optimizingmore » composite usage by combining traditional filament winding (FW) and advanced fiber placement (AFP) techniques. A numbers of vessels were manufactured in this project. The latest vessel design passed all the critical tests on the hybrid design per European Commission (EC) 79-2009 standard except the extreme temperature cycle test. The tests passed include burst test, cycle test, accelerated stress rupture test and drop test. It was discovered the location where AFP and FW overlap for load transfer could be weakened during hydraulic cycling at 85°C. To design a vessel that passed these tests, the in-house modeling software was updated to add capability to start and stop fiber layers to simulate the AFP process. The original in-house software was developed for filament winding only. Alternative fiber was also investigated in this project, but the added mass impacted the vessel cost negatively due to the lower performance from the alternative fiber. Overall the project was a success to show the hybrid design is a viable solution to reduce fiber usage, thus driving down the cost of fuel storage vessels. Based on DOE’s baseline vessel size of 147.3L and 91kg, the 129L vessel (scaled to DOE baseline) in this project shows a 32% composite savings and 20% cost savings when comparing Vessel 15 hybrid design and the Quantum
Energy cost of vessel disturbance to Kittlitz's Murrelets Brachyramphus brevirostris
Agness, Alison M.; Marshall, Kristin N.; Piatt, John F.; Ha, James C.; VanBlaricom, Glenn R.
2013-01-01
We evaluated the energy cost of vessel disturbance for individual Kittlitz’s Murrelets Brachyramphus brevirostris in Glacier Bay National Park and Preserve in Alaska, USA. We used Monte Carlo simulations to model the daily energy expense associated with flight from vessels by both breeding and non-breeding birds and evaluated risk based on both the magnitude of costs incurred and the degree to which the costs may be chronic. We used two scenarios of vessel disturbance for average- and peak-vessel traffic. Because they are more likely to fly away from vessels, non-breeding birds had a greater increase in energy expenditure when disturbed (up to 30% increase under the average scenario and >50% increase under the peak scenario) than breeders (up to 10% and 30% increases under the average and peak scenarios, respectively). Likewise, non-breeding birds were more likely to experience chronic increases in energy expense (i.e. a greater percentage of days with an increase in energy expenditure) than breeding birds. Our modeling results indicated that breeding and non-breeding birds were both susceptible to fitness consequences (e.g. reduced reproductive success and survival) resulting from the energy cost.
Development of a large low-cost double-chamber vacuum laminator
NASA Technical Reports Server (NTRS)
Burger, D. R.
1983-01-01
A double-chamber vacuum laminator was required to investigate the processing and control of the fabrication of large terrestrial photovoltaic modules, and economic problems arising therefrom. Major design considerations were low cost, process flexibility and the exploration of novel equipment approaches. Spherical end caps for industrial tanks were used for the vacuum chambers. A stepping programmer and adjustable timers were used for process flexibility. New processing options were obtained by use of vacuum sensors. The upper vacuum chamber was provided with a diaphragm support to reduce diaphragm stress. A counterweight was used for handling ease and safety. Heat was supplied by a large electrical strip heater. Thermal isolation and mechanical support were provided inexpensively by a bed of industrial marbles. Operational testing disclosed the need for a differential vacuum gauge and proportional valve. Reprogramming of the process control system was simple and quick.
Maritime vessel obsolescence, life cycle cost and design service life
NASA Astrophysics Data System (ADS)
Dinu, O.; Ilie, A. M.
2015-11-01
Maritime vessels have long service life and great costs of building, manning, operating, maintaining and repairing throughout their life. Major actions are needed to repair, renovate, sometime built or even replace those scrapped when technology or demand changes determine obsolescence. It is regarded as a concern throughout vessel's entire life cycle and reflects changes in expectation regarding performances in functioning, safety and environmental effects. While service live may differ from physical lives, expectations about physical lives is the main factors that determines design service life. Performance and failure are illustrated conceptually and represented in a simplified form considering the evolution of vessels parameters during its service life. In the proposed methodology an accumulated vessel lifecycle cost is analyzed and obsolescence is characterized from ship's design, performances, maintenance and management parameters point of view. Romanian ports feeding Black Sea are investigated in order to provide comprehensive information on: number and types of vessels, transport capacity and life cycle length. Recommendations are to be made in order to insure a best practice in lifecycle management in order to reduce costs.
Fernández-García, P; Marco-Doménech, S F; Lizán-Tudela, L; Ibáñez-Gual, M V; Navarro-Ballester, A; Casanovas-Feliu, E
To determine the cost effectiveness of breast biopsy by 9G vacuum-assisted guided by vertical stereotaxy or ultrasonography in comparison with breast biopsy by 14G core-needle biopsy and surgical biopsy. We analyzed a total of 997 biopsies (181 vacuum-assisted, 626 core, and 190 surgical biopsies). We calculated the total costs (indirect and direct) of the three types of biopsy. We did not calculate intangible costs. We measured the percentage of correct diagnoses obtained with each technique. To identify the most cost-effective option, we calculated the mean ratios for the three types of biopsies. Total costs were €225.09 for core biopsy, €638.90 for vacuum-assisted biopsy, and €1780.01 for surgical biopsy. The overall percentage of correct diagnoses was 91.81% for core biopsy, 94.03% for vacuum-assisted biopsy, and 100% for surgical biopsy; however, these differences did not reach statistical significance (p=0.3485). For microcalcifications, the percentage of correct diagnoses was 50% for core biopsy and 96.77% for vacuum-assisted biopsy (p<0.0001). For nodules, there were no significant differences among techniques. The mean cost-effectiveness ratio considering all lesions was 2.45 for core biopsy, 6.79 for vacuum-assisted biopsy, and 17.80 for surgical biopsy. Core biopsy was the dominant option for the diagnosis of suspicious breast lesions in general. However, in cases with microcalcifications, the low percentage of correct diagnoses achieved by core biopsy (50%) advises against its use in this context, where vacuum-assisted biopsy would be the technique of choice because it is more cost-effective than surgical biopsy, the other technique indicated for biopsying microcalcifications. Copyright © 2016 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.
Activation and Environmental Aspects of In-Vacuum Vessel Components of CFETR
NASA Astrophysics Data System (ADS)
Zhang, Xiaokang; Liu, Songlin; Zhu, Qingjun; Gao, Fangfang; Li, Jia
2016-11-01
The water-cooled ceramic breeder (WCCB) blanket is one of the three candidates of China's Fusion Engineering Test Reactor (CFETR). The evaluation of the radioactivity and decay heat produced by neutrons for the in-vacuum vessel components is essential for the assessment of radioactive wastes and the safety of CFETR. The activation calculation of CFETR in-vacuum vessel components was carried out by using the Monte Carlo N-Particle Transport Code MCNP, IAEA Fusion Evaluated Nuclear Data Library FENDL2.1, and the nuclear inventory code FISPACT-2007 and corresponding EAF-2007 libraries. In these analyses, the three-dimensional (3-D) neutronics model was employed and the WCCB blanket, the divertor, and the shield were modeled in detail to provide the detailed spatial distribution of the neutron flux and energy spectra. Then the neutron flux, energy spectra and the materials specification were transferred to FISPACT for the activation calculation with an assumed irradiation scenario of CFETR. This paper presents the main results of the activation analysis to evaluate the radioactivity, the decay heat, the contact dose, and the waste classification of the radioactive materials. At the time of shutdown, the activity of the WCCB blanket is 1.88×1019 Bq and the specific activity, the decay heat and the contact dose rate are 1.7 × 1013 Bq/kg, 3.05 MW, and 2.0 × 103 Sv/h respectively. After cooling for 100 years, 79% (4166.4 tons) radioactive wastes produced from the blanket, divertor, high temperature shield (HTS) and low temperature shield (LTS) need near surface disposal, while 21% (1112.3 tons) need geological disposal. According to results of the contact dose rate, all the components of the blanket, divertor, HTS and LTS could potentially be recycled after shutdown by using advanced remote handling equipment. In addition, the selection of Eurofer97 or RAFM for the divertor is better than that of SS316 because SS316 makes the activity of the divertor-body keep at a
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maslenikov, O.R.; Mraz, M.J.; Johnson, J.J.
1986-03-01
This report documents the seismic analyses performed by SMA for the MFTF-B Axicell vacuum vessel. In the course of this study we performed response spectrum analyses, CLASSI fixed-base analyses, and SSI analyses that included interaction effects between the vessel and vault. The response spectrum analysis served to benchmark certain modeling differences between the LLNL and SMA versions of the vessel model. The fixed-base analysis benchmarked the differences between analysis techniques. The SSI analyses provided our best estimate of vessel response to the postulated seismic excitation for the MFTF-B facility, and included consideration of uncertainties in soil properties by calculating responsemore » for a range of soil shear moduli. Our results are presented in this report as tables of comparisons of specific member forces from our analyses and the analyses performed by LLNL. Also presented are tables of maximum accelerations and relative displacements and plots of response spectra at various selected locations.« less
33 CFR 74.20-1 - Buoy and vessel use costs.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 7310 (series) which is available from the District Budget Office of the appropriate Coast Guard District Commander. (b) Buoy and vessel use charges under this part are made for the cost or value of time... obstruction. No charge for time and expense of Coast Guard vessels is made when the marking of the obstruction...
33 CFR 74.20-1 - Buoy and vessel use costs.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 7310 (series) which is available from the District Budget Office of the appropriate Coast Guard District Commander. (b) Buoy and vessel use charges under this part are made for the cost or value of time... obstruction. No charge for time and expense of Coast Guard vessels is made when the marking of the obstruction...
Design of the ZTH vacuum liner
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prince, P.P.; Dike, R.S.
1987-01-01
The current status of the ZTH vacuum liner design is covered by this report. ZTH will be the first experiment to be installed in the CPRF (Confinement Physics Research Facility) at the Los Alamos National Laboratory and is scheduled to be operational at the rated current of 4 MA in 1992. The vacuum vessel has a 2.4 m major radius and a 40 cm minor radius. Operating parameters which drive the vacuum vessel mechanical design include a 300 C bakeout temperature, an armour support system capable of withstanding 25 kV, a high toroidal resistance, 1250 kPa magnetic loading, a 10more » minute cycle time, and high positional accuracy with respect to the conducting shell. The vacuum vessel design features which satisfy the operating parameters are defined. The liner is constructed of Inconel 625 and has a geometry which alternates sections of thin walled bellows with rigid ribs. These composite sections span between pairs of the 16 diagnostic stations to complete the torus. The thin bellows sections maximize the liner toroidal resistance and the ribs provide support and positional accuracy for the armour in relation to the conducting shell. Heat transfer from the vessel is controlled by a blanket wrap of ceramic fiber insulation and the heat flux is dissipated to a water cooling jacket in the conducting shell.« less
Vacuum packing: a model system for laboratory-scale silage fermentations.
Johnson, H E; Merry, R J; Davies, D R; Kell, D B; Theodorou, M K; Griffith, G W
2005-01-01
To determine the utility of vacuum-packed polythene bags as a convenient, flexible and cost-effective alternative to fixed volume glass vessels for lab-scale silage studies. Using perennial ryegrass or red clover forage, similar fermentations (as assessed by pH measurement) occurred in glass tube and vacuum-packed silos over a 35-day period. As vacuum-packing devices allow modification of initial packing density, the effect of four different settings (initial packing densities of 0.397, 0.435, 0.492 and 0.534 g cm(-3)) on the silage fermentation over 16 days was examined. Significant differences in pH decline and lactate accumulation were observed at different vacuum settings. Gas accumulation was apparent within all bags and changes in bag volume with time was observed to vary according to initial packing density. Vacuum-packed silos do provide a realistic model system for lab-scale silage fermentations. Use of vacuum-packed silos holds potential for lab-scale evaluations of silage fermentations, allowing higher throughput of samples, more consistent packing as well as the possibility of investigating the effects of different initial packing densities and use of different wrapping materials.
A low cost imaging displacement measurement system for spacecraft thermal vacuum testing
NASA Technical Reports Server (NTRS)
Dempsey, Brian
2006-01-01
A low cost imaging displacement technique suitable for use in thermal vacuum testing was built and tested during thermal vacuum testing of the space infrared telescope facility (SIRTF, later renamed Spitzer infrared telescope facility). The problem was to measure the relative displacement of different portions of the spacecraft due to thermal expansion or contraction. Standard displacement measuring instrumentation could not be used because of the widely varying temperatures on the spacecraft and for fear of invalidating the thermal vacuum testing. The imaging system was conceived, designed, purchased, and installed in approximately 2 months at very low cost. The system performed beyond expectations proving that sub millimeter displacements could be measured from over 2 meters away. Using commercial optics it was possible to make displacement measurements down to 10 (mu)m. An automated image processing tool was used to process the data, which not only speeded up data reduction, but showed that velocities and accelerations could also be measured. Details of the design and capabilities of the system are discussed along with the results of the test on the observatory. Several images from the actual test are presented.
33 CFR 74.20-1 - Buoy and vessel use costs.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Buoy and vessel use costs. 74.20-1 Section 74.20-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Aids to Navigation Costs § 74.20-1 Buoy...
33 CFR 74.20-1 - Buoy and vessel use costs.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Buoy and vessel use costs. 74.20-1 Section 74.20-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Aids to Navigation Costs § 74.20-1 Buoy...
33 CFR 74.20-1 - Buoy and vessel use costs.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Buoy and vessel use costs. 74.20-1 Section 74.20-1 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY AIDS TO NAVIGATION CHARGES FOR COAST GUARD AIDS TO NAVIGATION WORK Aids to Navigation Costs § 74.20-1 Buoy...
Bowers, Joel M.
1994-01-01
An improved evacuated optical structure is disclosed comprising an optical bench mounted in a vacuum vessel in a manner which inhibits transmission of movement of the vacuum vessel to the optical bench, yet provides a compact and economical structure. The vacuum vessel is mounted, through a sidewall thereof, to a support wall at four symmetrically positioned and spaced apart areas, each of which comprises a symmetrically positioned group of mounting structures passing through the sidewall of the vacuum vessel. The optical bench is pivotally secured to the vacuum vessel by four symmetrically spaced apart bolts and spherical bearings, each of which is centrally positioned within one of the four symmetrically positioned groups of vacuum vessel mounting structures. Cover plates and o-ring seals are further provided to seal the vacuum vessel mounting structures from the interior of the vacuum vessel, and venting bores are provided to vent trapped gases in the bores used to secure the cover plates and o-rings to the vacuum vessel. Provision for detecting leaks in the mounting structures from the rear surface of the vacuum vessel sidewall facing the support wall are also provided. Deflection to the optical bench within the vacuum vessel is further minimized by tuning the structure for a resonant frequency of at least 100 Hertz.
Bowers, J.M.
1994-04-19
An improved evacuated optical structure is disclosed comprising an optical bench mounted in a vacuum vessel in a manner which inhibits transmission of movement of the vacuum vessel to the optical bench, yet provides a compact and economical structure. The vacuum vessel is mounted, through a sidewall thereof, to a support wall at four symmetrically positioned and spaced apart areas, each of which comprises a symmetrically positioned group of mounting structures passing through the sidewall of the vacuum vessel. The optical bench is pivotally secured to the vacuum vessel by four symmetrically spaced apart bolts and spherical bearings, each of which is centrally positioned within one of the four symmetrically positioned groups of vacuum vessel mounting structures. Cover plates and o-ring seals are further provided to seal the vacuum vessel mounting structures from the interior of the vacuum vessel, and venting bores are provided to vent trapped gases in the bores used to secure the cover plates and o-rings to the vacuum vessel. Provision for detecting leaks in the mounting structures from the rear surface of the vacuum vessel sidewall facing the support wall are also provided. Deflection to the optical bench within the vacuum vessel is further minimized by tuning the structure for a resonant frequency of at least 100 Hertz. 10 figures.
Changing vessel routes could significantly reduce the cost of future offshore wind projects.
Samoteskul, Kateryna; Firestone, Jeremy; Corbett, James; Callahan, John
2014-08-01
With the recent emphasis on offshore wind energy Coastal and Marine Spatial Planning (CMSP) has become one of the main frameworks used to plan and manage the increasingly complex web of ocean and coastal uses. As wind development becomes more prevalent, existing users of the ocean space, such as commercial shippers, will be compelled to share their historically open-access waters with these projects. Here, we demonstrate the utility of using cost-effectiveness analysis (CEA) to support siting decisions within a CMSP framework. In this study, we assume that large-scale offshore wind development will take place in the US Mid-Atlantic within the next decades. We then evaluate whether building projects nearshore or far from shore would be more cost-effective. Building projects nearshore is assumed to require rerouting of the commercial vessel traffic traveling between the US Mid-Atlantic ports by an average of 18.5 km per trip. We focus on less than 1500 transits by large deep-draft vessels. We estimate that over 29 years of the study, commercial shippers would incur an additional $0.2 billion (in 2012$) in direct and indirect costs. Building wind projects closer to shore where vessels used to transit would generate approximately $13.4 billion (in 2012$) in savings. Considering the large cost savings, modifying areas where vessels transit needs to be included in the portfolio of policies used to support the growth of the offshore wind industry in the US. Copyright © 2014 Elsevier Ltd. All rights reserved.
Grady, Ian; Vasquez, Tony; Tawfik, Sara; Grady, Sean
2017-03-01
To evaluate the cost-efficacy of vacuum-assisted ultrasound-guided breast biopsy instruments compared to ultrasound-guided 14-gauge spring-loaded core-needle biopsy. The American Society of Breast Surgeons' Mastery of Breast Surgery Registry was reviewed. Biopsy findings, any rebiopsy, and the instrument used were abstracted for 31,451 ultrasound-guided biopsy procedures performed between 2001 and July 2014. Rates of cancer diagnosis and rebiopsy were calculated for each instrument. A linear mathematical model was developed to calculate total cost per cancer diagnosis, including procedural costs and the costs of any additional surgical rebiopsy procedures. Mean cost per cancer diagnosis with confidence limits was then determined for 14-gauge spring-loaded core-needle biopsy and 14 different vacuum-assisted instruments. For 14-gauge spring-loaded core-needle biopsy, mean cost per cancer diagnosis was $4346 (4327-$4366). For the vacuum-assisted instruments, mean cost per cancer diagnosis ranged from a low of $3742 ($3732-$3752) to a high of $4779 ($4750-$4809). Vacuum-assisted instruments overall were more cost-effective than core with a mean cost per cancer diagnosis of $4052 ($4038-$4067) (p < 0.05). Tethered vacuum-assisted instruments performed best with a mean cost per cancer diagnosis of $3978 ($3964-$3991) (p < 0.05). Nontethered devices had a mean cost per cancer diagnosis of $4369 ($4350-$4388), a result no better than core (p < 0.05). Ultrasound-guided vacuum-assisted breast biopsy had a lower mean cost per cancer diagnosis than 14-gauge spring-loaded core-needle biopsy. This advantage was only seen in tethered vacuum-assisted instruments. Within device families, larger instruments tended to outperform smaller instruments.
Overall behaviour of PFC integrated SST-1 vacuum system
NASA Astrophysics Data System (ADS)
Khan, Ziauddin; Raval, Dilip C.; Paravasu, Yuvakiran; Semwal, Pratibha; Dhanani, Kalpeshkumar R.; George, Siju; Shoaib, Mohammad; Prakash, Arun; Babu, Gattu R.; Thankey, Prashant; Pathan, Firozkhan S.; Pradhan, Subrata
2017-04-01
As a part of phase-I up-gradation of Steady-state Superconducting Tokamak (SST-1), Graphite Plasma Facing Components (PFCs) have been integrated inside SST-1 vacuum vessel as a first wall (FW) during Nov 14 and May 2015. The SST-1 FW has a total surface area of the installed PFCs exposed to plasma is ∼ 40 m2 which is nearly 50% of the total surface area of stainless steel vacuum chamber (∼75 m2). The volume of the vessel within the PFCs is ∼ 16 m3. After the integration of PFCs, the entire vessel as well as the PFC cooling/baking circuits has been qualified with an integrated helium leak tightness of < 1.0 x 10-8 mbar 1/s. The pumping system of the SST-1 vacuum vessel comprises of one number of Roots’ pump, four numbers of turbomolecular pumps and a cryopump. After the initial pump down, the PFCs were baked at 250 °C for nearly 20 hours employing hot nitrogen gas to remove the absorbed water vapours. Thereafter, Helium glow discharges cleaning were carried out towards the removal of surface impurities. The pump down characteristics of SST-1 vacuum chamber and the changes in the residual gaseous impurities after the installation of the PFCs will be discussed in this paper.
Shore Power for Vessels Calling at U.S. Ports: Benefits and Costs.
Vaishnav, Parth; Fischbeck, Paul S; Morgan, M Granger; Corbett, James J
2016-02-02
When in port, ships burn marine diesel in on-board generators to produce electricity and are significant contributors to poor local and regional air quality. Supplying ships with grid electricity can reduce these emissions. We use two integrated assessment models to quantify the benefits of reducing the emissions of NOX, SO2, PM2.5, and CO2 that would occur if shore power were used. Using historical vessel call data, we identify combinations of vessels and berths at U.S. ports that could be switched to shore power to yield the largest gains for society. Our results indicate that, depending on the social costs of pollution assumed, an air quality benefit of $70-150 million per year could be achieved by retrofitting a quarter to two-thirds of all vessels that call at U.S. ports. Such a benefit could be produced at no net cost to society (health and environmental benefits would be balanced by the cost of ship and port retrofit) but would require many ships to be equipped to receive shore power, even if doing so would result in a private loss for the operator. Policy makers could produce a net societal gain by implementing incentives and mandates to encourage a shift toward shore power.
Analysis and Design of Cryogenic Pressure Vessels for Automotive Hydrogen Storage
NASA Astrophysics Data System (ADS)
Espinosa-Loza, Francisco Javier
Cryogenic pressure vessels maximize hydrogen storage density by combining the high pressure (350-700 bar) typical of today's composite pressure vessels with the cryogenic temperature (as low as 25 K) typical of low pressure liquid hydrogen vessels. Cryogenic pressure vessels comprise a high-pressure inner vessel made of carbon fiber-coated metal (similar to those used for storage of compressed gas), a vacuum space filled with numerous sheets of highly reflective metalized plastic (for high performance thermal insulation), and a metallic outer jacket. High density of hydrogen storage is key to practical hydrogen-fueled transportation by enabling (1) long-range (500+ km) transportation with high capacity vessels that fit within available spaces in the vehicle, and (2) reduced cost per kilogram of hydrogen stored through reduced need for expensive structural material (carbon fiber composite) necessary to make the vessel. Low temperature of storage also leads to reduced expansion energy (by an order of magnitude or more vs. ambient temperature compressed gas storage), potentially providing important safety advantages. All this is accomplished while simultaneously avoiding fuel venting typical of cryogenic vessels for all practical use scenarios. This dissertation describes the work necessary for developing and demonstrating successive generations of cryogenic pressure vessels demonstrated at Lawrence Livermore National Laboratory. The work included (1) conceptual design, (2) detailed system design (3) structural analysis of cryogenic pressure vessels, (4) thermal analysis of heat transfer through cryogenic supports and vacuum multilayer insulation, and (5) experimental demonstration. Aside from succeeding in demonstrating a hydrogen storage approach that has established all the world records for hydrogen storage on vehicles (longest driving range, maximum hydrogen storage density, and maximum containment of cryogenic hydrogen without venting), the work also
Basic experiments during loss of vacuum event (LOVE) in fusion experimental reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ogawa, Masuro; Kunugi, Tomoaki; Seki, Yasushi
If a loss of vacuum event (LOVE) occurs due to damage of the vacuum vessel of a nuclear fusion experimental reactor, some chemical reactions such as a graphic oxidation and a buoyancy-driven exchange flow take place after equalization of the gas pressure between the inside and outside of the vacuum vessel. The graphite oxidation would generate inflammable carbon monoxide and release tritium retained in the graphite. The exchange flow through the breaches may transport the carbon monoxide and tritium out of the vacuum vessel. To add confidence to the safety evaluations and analyses, it is important to grasp the basicmore » phenomena such as the exchange flow and the graphite oxidation. Experiments of the exchange flow and the graphite oxidation were carried out to obtain the exchange flow rate and the rate constant for the carbon monoxide combustion, respectively. These experimental results were compared with existing correlations. The authors plan a scaled-model test and a full-scale model test for the LOVE.« less
Versatile, low-cost, computer-controlled, sample positioning system for vacuum applications
NASA Technical Reports Server (NTRS)
Vargas-Aburto, Carlos; Liff, Dale R.
1991-01-01
A versatile, low-cost, easy to implement, microprocessor-based motorized positioning system (MPS) suitable for accurate sample manipulation in a Second Ion Mass Spectrometry (SIMS) system, and for other ultra-high vacuum (UHV) applications was designed and built at NASA LeRC. The system can be operated manually or under computer control. In the latter case, local, as well as remote operation is possible via the IEEE-488 bus. The position of the sample can be controlled in three linear orthogonal and one angular coordinates.
Modeling and Analysis of Alternative Concept of ITER Vacuum Vessel Primary Heat Transfer System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carbajo, Juan J; Yoder Jr, Graydon L; Dell'Orco, Giovanni
2010-01-01
A RELAP5-3D model of the ITER (Latin for the way ) vacuum vessel (VV) primary heat transfer system has been developed to evaluate a proposed design change that relocates the heat exchangers (HXs) from the exterior of the tokamak building to the interior. This alternative design protects the HXs from external hazards such as wind, tornado, and aircraft crash. The proposed design integrates the VV HXs into a VV pressure suppression system (VVPSS) tank that contains water to condense vapour in case of a leak into the plasma chamber. The proposal is to also use this water as the ultimatemore » sink when removing decay heat from the VV system. The RELAP5-3D model has been run under normal operating and abnormal (decay heat) conditions. Results indicate that this alternative design is feasible, with no effects on the VVPSS tank under normal operation and with tank temperature and pressure increasing under decay heat conditions resulting in a requirement to remove steam generated if the VVPSS tank low pressure must be maintained.« less
NASA Astrophysics Data System (ADS)
Kim, Sang-Young; Shim, Chun Sik; Sturtevant, Caleb; Kim, Dave (Dae-Wook); Song, Ha Cheol
2014-09-01
Glass Fiber Reinforced Plastic (GFRP) structures are primarily manufactured using hand lay-up or vacuum infusion techniques, which are cost-effective for the construction of marine vessels. This paper aims to investigate the mechanical properties and failure mechanisms of the hybrid GFRP composites, formed by applying the hand lay-up processed exterior and the vacuum infusion processed interior layups, providing benefits for structural performance and ease of manufacturing. The hybrid GFRP composites contain one, two, and three vacuum infusion processed layer sets with consistent sets of hand lay-up processed layers. Mechanical properties assessed in this study include tensile, compressive and in-plane shear properties. Hybrid composites with three sets of vacuum infusion layers showed the highest tensile mechanical properties while those with two sets had the highest mechanical properties in compression. The batch homogeneity, for the GFRP fabrication processes, is evaluated using the experimentally obtained mechanical properties
Vacuum Studies of a Prototype Composite Coil Dewar for HTSC Transformers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schwenterly, S W; Zhang, Y.; Pleva, E. F.
Oak Ridge National Laboratory (ORNL) is collaborating with Waukesha Electric Systems (WES) to develop a high-temperature superconducting (HTSC) utility power transformer with primary and secondary coils cooled by liquid nitrogen. Since the vacuum-insulated cryogenic coil dewar surrounds the magnetic core limb and cannot form a shorted turn, non-conductive materials are required. Two test vessels and a small prototype dewar have been fabricated by Scorpius Space Launch Company with epoxy/fiberglass composites, using their proprietary PRESSURMAXX vessel technology. The effects of pumping time, bakeout temperature, and cryogenic vessel temperature on vacuum outgassing rates have been investigated. Outgassing rates of the individual materialsmore » used in vessel construction have also been measured. The results will be scaled up to determine the required pumping capacity for a full-size 25-MVA commercial transformer dewar.« less
NASA Technical Reports Server (NTRS)
Swanger, Adam M.; Notardonato, William U.; Jumper, Kevin M.
2015-01-01
The Ground Operations Demonstration Unit for Liquid Hydrogen (GODU-LH2) has been developed at NASA Kennedy Space Center in Florida. GODU-LH2 has three main objectives: zero-loss storage and transfer, liquefaction, and densification of liquid hydrogen. A cryogenic refrigerator has been integrated into an existing, previously certified, 33,000 gallon vacuum-jacketed storage vessel built by Minnesota Valley Engineering in 1991 for the Titan program. The dewar has an inner diameter of 9.5 and a length of 71.5; original design temperature and pressure ranges are -423 F to 100 F and 0 to 95 psig respectively. During densification operations the liquid temperature will be decreased below the normal boiling point by the refrigerator, and consequently the pressure inside the inner vessel will be sub-atmospheric. These new operational conditions rendered the original certification invalid, so an effort was undertaken to recertify the tank to the new pressure and temperature requirements (-12.7 to 95 psig and -433 F to 100 F respectively) per ASME Boiler and Pressure Vessel Code, Section VIII, Division 1. This paper will discuss the unique design, analysis and implementation issues encountered during the vessel recertification process.
Zollinger, William T.
1993-01-01
Apparatus for manipulating a vacuum hose in a reactor vessel comprises a housing with two opposing openings, an arm carried by the housing and deployable from a stowed position essentially completely within the housing to an extended position where the arm extends through the two openings in a generally horizontal position. The arm preferably has a two-fingered gripping device for gripping the vacuum hose but may carry a different end effector such as a grinding wheel. The fingers are opened and closed by one air cylinder. A second air cylinder extends the device. A third air cylinder within the housing pivotally pulls the opposing end of the arm into the housing via a pivoting member pivotally connected between the third air cylinder shaft and the arm.
Mengelkoch, Larry J; Clark, Kirby
2006-03-01
The purpose of this study was to evaluate two types of industrial vacuum cleaners, in terms of cleaning rates, energy expenditure, and perceived exertion. Twelve industrial cleaners (six males and six females, age 28-39 yr) performed two 1-h vacuuming tasks with an upright vacuum cleaner (UVC) and a backpack vacuum cleaner (BPVC). Measures for oxygen uptake (VO2) and ratings of perceived exertion (RPE) were collected continuously during the 1-h vacuuming tasks. Cleaning rates for the UVC and BPVC were 7.23 and 14.98 m2min(-1), respectively. On a separate day subjects performed a maximal treadmill exercise test to determine their maximal aerobic capacity (peak VO2). Average absolute energy costs (in Metabolic equivalents), relative energy costs of the vacuum task compared to the subjects' maximal aerobic capacity (% peak VO2), and RPE responses for the 1-h vacuuming tasks were similar between vacuum cleaners, but % peak VO2 and RPE values differed between genders. These results indicate that the BPVC was more efficient than the UVC. With the BPVC, experienced workers vacuumed at a cleaning rate 2.07 times greater than the UVC and had similar levels of energy expenditure and perceived effort, compared to the slower cleaning rate with the UVC.
Cryogenic Vacuum Insulation for Vessels and Piping
NASA Technical Reports Server (NTRS)
Kogan, A.; Fesmire, J.; Johnson, W.; Minnick, J.
2010-01-01
Cryogenic vacuum insulation systems, with proper materials selection and execution, can offer the highest levels of thermal performance. Three areas of consideration are vital to achieve the optimum result: materials, representative test conditions, and engineering approach for the particular application. Deficiency in one of these three areas can prevent optimum performance and lead to severe inefficiency. Materials of interest include micro-fiberglass, multilayer insulation, and composite arrangements. Cylindrical liquid nitrogen boil-off calorimetry methods were used. The need for standard thermal conductivity data is addressed through baseline testing. Engineering analysis and design factors such as layer thickness, density, and practicality are also considered.
Optimized Baking of the DIII-D Vessel
DOE Office of Scientific and Technical Information (OSTI.GOV)
P.M. Anderson; A.G. Kellman
The DIII-D tokamak vacuum vessel baking system is used to heat the vessel walls and internal hardware to an average temperature of 350 C to allow rapid conditioning of the vacuum surfaces. The system combines inductive heating and a circulating hot air system to provide rapid heating with temperature uniformity required by stress considerations. In recent years, the time to reach 350 C had increased from 9 hrs to 14 hrs. To understand and remedy this sluggish heating rate, an evaluation of the baking system was recently performed. The evaluation indicated that the mass of additional in-vessel hardware (50% increasemore » in mass) was primarily responsible. This paper reports on this analysis and the results of the addition of an electric air heater and procedural changes that have been implemented. Preliminary results indicate that the time to 350 C has been decreased to 4.5 hours and the temperature uniformity has improved.« less
NASA Astrophysics Data System (ADS)
Zhang, Linna; Zhang, Shengzhao; Sun, Meixiu; Li, Hongxiao; Li, Yingxin; Fu, Zhigang; Guan, Yang; Li, Gang; Lin, Ling
2017-03-01
Discrimination of human and nonhuman blood is crucial for import-export ports and inspection and quarantine departments. Current methods are usually destructive, complicated and time-consuming. We had previously demonstrated that visible diffuse reflectance spectroscopy combining PLS-DA method can successfully realize human blood discrimination. In that research, the spectra were measured with the fiber probe under the surface of blood samples. However, open sampling may pollute the blood samples. Virulence factors in blood samples can also endanger inspectors. In this paper, we explored the classification effect with the blood samples measured in the original containers-vacuum blood vessel. Furthermore, we studied the impact of different conditions of blood samples, such as coagulation and hemolysis, on the prediction ability of the discrimination model. The calibration model built with blood samples in different conditions displayed a satisfactory prediction result. This research demonstrated that visible and near-infrared diffuse reflectance spectroscopy method was potential for noncontact discrimination of human blood.
ITER-FEAT vacuum vessel and blanket design features and implications for the R&D programme
NASA Astrophysics Data System (ADS)
Ioki, K.; Dänner, W.; Koizumi, K.; Krylov, V. A.; Cardella, A.; Elio, F.; Onozuka, M.; ITER Joint Central Team; ITER Home Teams
2001-03-01
A configuration in which the vacuum vessel (VV) fits tightly to the plasma aids the passive plasma vertical stability, and ferromagnetic material in the VV reduces the toroidal field ripple. The blanket modules are supported directly by the VV. A full scale VV sector model has provided critical information related to fabrication technology and for testing the magnitude of welding distortions and achievable tolerances. This R&D validated the fundamental feasibility of the double wall VV design. The blanket module configuration consists of a shield body to which a separate first wall is mounted. The separate first wall has a facet geometry consisting of multiple flat panels, where 3-D machining will not be required. A configuration with deep slits minimizes the induced eddy currents and loads. The feasibility and robustness of solid hot isostatic pressing joining were demonstrated in the R&D by manufacturing and testing several small and medium scale mock-ups and finally two prototypes. Remote handling tests and assembly tests of a blanket module have demonstrated the basic feasibility of its installation and removal.
Zollinger, W.T.
1993-11-23
Apparatus for manipulating a vacuum hose in a reactor vessel comprises a housing with two opposing openings, an arm carried by the housing and deployable from a stowed position essentially completely within the housing to an extended position where the arm extends through the two openings in a generally horizontal position. The arm preferably has a two-fingered gripping device for gripping the vacuum hose but may carry a different end effector such as a grinding wheel. The fingers are opened and closed by one air cylinder. A second air cylinder extends the device. A third air cylinder within the housing pivotally pulls the opposing end of the arm into the housing via a pivoting member pivotally connected between the third air cylinder shaft and the arm. 6 figures.
Bakeout Chamber Within Vacuum Chamber
NASA Technical Reports Server (NTRS)
Taylor, Daniel M.; Soules, David M.; Barengoltz, Jack B.
1995-01-01
Vacuum-bakeout apparatus for decontaminating and measuring outgassing from pieces of equipment constructed by mounting bakeout chamber within conventional vacuum chamber. Upgrade cost effective: fabrication and installation of bakeout chamber simple, installation performed quickly and without major changes in older vacuum chamber, and provides quantitative data on outgassing from pieces of equipment placed in bakeout chamber.
Metal vapor vacuum arc switching - Applications and results. [for launchers
NASA Technical Reports Server (NTRS)
Cope, D.; Mongeau, P.
1984-01-01
The design of metal-vapor vacuum-arc switches (MVSs) for electromagnetic launchers is discussed, and preliminary results are presented for an experimental MVS. The general principles of triggered-vacuum-gap and vacuum-interrupter MVSs are reviewed, and the requirements of electromagnetic launchers are analyzed. High-current design problems such as electrode erosion, current sharing, magnetic effects, and thermal effects are examined. The experimental MVS employs stainless-steel flanges, a glass vacuum vessel, an adjustable electrode gap, autonomous internal magnetic-field coils, and a tungsten-pin trigger assembly. Some results from tests without magnetic augmentation are presented graphically.
Analysis of RFQ vacuum system for HINS tests at MDB
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piekarz, Henryk; /Fermilab
The arrangement of RFQ vacuum system is briefly described. The projections of the vacuum level using standard out-gassing rates for the RFQ major components are compared with measurements. The permeation of water through the Viton O-rings of the LCW manifold inside the RFQ vacuum vessel is analyzed and compared with RGA data. A model where the out-gassing water from the vanes inner surfaces affects seriously RFQ operation is devised and compared with RFQ performance. The rate of a hydrogen gas spill from the LEBT into the RFQ vacuum space is also projected. Suggestions to correct and improve RFQ operation aremore » presented.« less
Manufacturing and assembly of IWS support rib and lower bracket for ITER vacuum vessel
NASA Astrophysics Data System (ADS)
Laad, R.; Sarvaiya, Y.; Pathak, H. A.; Raval, J. R.; Choi, C. H.
2017-04-01
ITER Vacuum Vessel (VV) is made of double walls connected by ribs structure and flexible housings. Space between these walls is filled up with In Wall Shielding (IWS) blocks to (1) shield neutrons streaming out of plasma and (2) reduce toroidal magnetic field ripple. These blocks will be connected to the VV through a supporting structure of Support Rib (SR) and Lower Bracket (LB) assembly. SR and LB are two independent components manufactured from SS 316L(N)-IG, Total 1584 support ribs and 3168 lower bracket of different sizes and shapes will be manufactured for the IWS. Two lower brackets will be welded with one support rib to make an assembly. The welding between SR and LB is a full penetration welding. Total 1584 assemblies of different sizes and shapes will be manufactured. Sufficient experience gained from manufacturing and testing of mock ups, final manufacturing of IWS support rib and lower bracket has been started at the site of IWS manufacturer M/s. Avasarala Technologies Limited (ATL). This paper will describe, optimization of water jet cutting speed on IWS material, selection criteria for K type weld joint, unique features of fixture of assembly, manufacturing of Mock ups, and welding processes with NDTs.
Thin film application device and method for coating small aperture vacuum vessels
Walters, Dean R; Este, Grantley O
2015-01-27
A device and method for coating an inside surface of a vessel is provided. In one embodiment, a coating device comprises a power supply and a diode in electrical communication with the power supply, wherein electrodes comprising the diode reside completely within the vessel. The method comprises reversibly sealing electrodes in a vessel, sputtering elemental metal or metal compound on the surface while maintaining the surface in a controlled atmosphere.
NASA Astrophysics Data System (ADS)
Khan, Ziauddin; Pathan, Firozkhan S.; Yuvakiran, Paravastu; George, Siju; Manthena, Himabindu; Raval, Dilip C.; Thankey, Prashant L.; Dhanani, Kalpesh R.; Gupta, Manoj Kumar; Pradhan, Subrata
2012-11-01
SST-1 Tokamak, a steady state super-conducting device, is under refurbishment to demonstrate the plasma discharge for the duration of 1000 second. The major fabricated components of SST-1 like vacuum vessel, thermal shields, superconducting magnets etc have to be tested for their functional parameters. During machine operation, vacuum vessel will be baked at 150 °C, thermal shields will be operated at 85 K and magnet system will be operated at 4.5 K. All these components must have helium leak tightness under these conditions so far as the machine operation is concerned. In order to validate the helium leak tightness of these components, in-house high vacuum chamber is fabricated. This paper describes the analysis, design and fabrication of high vacuum chamber to demonstrate these functionalities. Also some results will be presented.
Silicon crystal growth in vacuum
NASA Technical Reports Server (NTRS)
Khattak, C. P.; Schmid, F.
1982-01-01
The most developed process for silicon crystal growth is the Czochralski (CZ) method which was in production for over two decades. In an effort to reduce cost of single crystal silicon for photovoltaic applications, a directional solidification technique, Heat Exchanger Method (HEM), was adapted. Materials used in HEM and CZ furnaces are quite similar (heaters, crucibles, insulation, etc.). To eliminate the cost of high purity argon, it was intended to use vacuum operation in HEM. Two of the major problems encountered in vacuum processing of silicon are crucible decomposition and silicon carbide formation in the melt.
46 CFR 154.1335 - Pressure and vacuum protection.
Code of Federal Regulations, 2012 CFR
2012-10-01
... audible and visual alarm at the cargo control station, and a remote group alarm in the wheelhouse. (c) If... SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and...) Has remote readouts at the cargo control station. (2) If vacuum protection is required under § 154.804...
46 CFR 154.1335 - Pressure and vacuum protection.
Code of Federal Regulations, 2011 CFR
2011-10-01
... audible and visual alarm at the cargo control station, and a remote group alarm in the wheelhouse. (c) If... SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and...) Has remote readouts at the cargo control station. (2) If vacuum protection is required under § 154.804...
46 CFR 154.1335 - Pressure and vacuum protection.
Code of Federal Regulations, 2013 CFR
2013-10-01
... audible and visual alarm at the cargo control station, and a remote group alarm in the wheelhouse. (c) If... SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and...) Has remote readouts at the cargo control station. (2) If vacuum protection is required under § 154.804...
46 CFR 154.1335 - Pressure and vacuum protection.
Code of Federal Regulations, 2010 CFR
2010-10-01
... audible and visual alarm at the cargo control station, and a remote group alarm in the wheelhouse. (c) If... SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and...) Has remote readouts at the cargo control station. (2) If vacuum protection is required under § 154.804...
Understanding microwave vessel contamination by chloride species.
Recchia, Sandro; Spanu, Davide; Bianchi, Davide; Dossi, Carlo; Pozzi, Andrea; Monticelli, Damiano
2016-10-01
Microwaves are widely used to assist digestion, general sample treatment and synthesis. The use of aqua regia is extensively adopted for the closed vessel mineralization of samples prior to trace element detection, leading to the contamination of microwave vessels by chlorine containing species. The latter are entrapped in the polymeric matrix of the vessels, leading to memory effects that are difficult to remove, among which the risk of silver incomplete recoveries by removal of the sparingly soluble chloride is the predominant one. In the present paper, we determined by mass spectrometry that hydrogen chloride is the species entrapped in the polymeric matrix and responsible for vessel contamination. Moreover, several decontamination treatments were considered to assess their efficiency, demonstrating that several cleaning cycles with water, nitric acid or silver nitrate in nitric acid were inefficient in removing chloride contamination (contamination reduction around 90%). Better results (≈95% decrease) were achieved by a single decontamination step in alkaline environment (sodium hydroxide or ammonia). Finally, a thermal treatment in a common laboratory oven (i.e. without vacuum and ventilation) was tested: a one hour heating at 150°C leads to a 98.5% decontamination, a figure higher than the ones obtained by wet treatments which requires comparable time. The latter treatment is a major advancement with respect to existing treatments as it avoids the need of a vacuum oven for at least 17h as presently proposed in the literature. Copyright © 2016 Elsevier B.V. All rights reserved.
Tritium release from SS316 under vacuum condition
DOE Office of Scientific and Technical Information (OSTI.GOV)
Torikai, Y.; Penzhorn, R.D.
The plasma facing surface of the ITER vacuum vessel, partly made of low carbon austenitic stainless steel type 316L, will incorporate tritium during machine operation. In this paper the kinetics of tritium release from stainless steel type 316 into vacuum and into a noble gas stream are compared and modelled. Type 316 stainless steel specimens loaded with tritium either by exposure to 1.2 kPa HT at 573 K or submersion into liquid HTO at 298 K showed characteristic thin surface layers trapping tritium in concentrations far higher than those determined in the bulk. The evolution of the tritium depth profilemore » in the bulk during heating under vacuum was non-discernible from that of tritium liberated into a stream of argon. Only the relative amount of the two released tritium-species, i.e. HT or HTO, was different. Temperature-dependent depth profiles could be predicted with a one-dimensional diffusion model. Diffusion coefficients derived from fitting of the tritium release into an evacuated vessel or a stream of argon were found to be (1.4 ± 1.0)*10{sup -7} and (1.3 ± 0.9)*10{sup -9} cm{sup 2}/s at 573 and 423 K, respectively. Polished surfaces on type SS316 stainless steel inhibit considerably the thermal release rate of tritium.« less
46 CFR 98.30-3 - Vessels carrying MPTs.
Code of Federal Regulations, 2013 CFR
2013-10-01
... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Portable Tanks § 98.30-3... corrosion-resistant tag— (a) An inspection date for pressure relief devices and vacuum relief devices in...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dameron, Arrelaine
During the duration of this CRADA, V-Glass and NREL will partner in testing, analysis, performance forecasting, costing, and evaluation of V-Glass’s GRIPWELD™ process technology for creating a low cost hermetic seal for conventional and vacuum glazing. Upon successful evaluation of hermeticity, V-Glass’s GRIPWELD™ will be evaluated for its potential use in highly insulating window glazing.
Vacuum pumps and systems: A review of current practice
NASA Technical Reports Server (NTRS)
Giles, Stuart
1986-01-01
A review of the fundamental characteristics of the many types of vacuum pumps and vacuum pumping systems is given. The optimum pumping range, relative cost, performance limitations, maintenance problems, system operating costs and similar subjects are discussed. Experiences from the thin film deposition, chemical processing, material handling, food processing and other industries, as well as space simulation are used to support conclusions and recommendations.
Impact of stereotactic 11-g vacuum-assisted breast biopsy on cost of diagnosis in Austria.
Gruber, R; Walter, E; Helbich, T H
2011-01-01
To determine the frequency with which stereotactic 11-g vacuum-assisted breast biopsy (11-g SVAB) obviates an open surgical biopsy (OSB), to compare the costs of these two biopsy methods, and to estimate the potential cost savings attributable to 11-g SVAB in the diagnosis of suspicious breast lesions in patients in Austria. We retrospectively reviewed 318 consecutive breast lesions of BI-RADS categories IV and V (microcalcifications n=166; masses n=152) on which 11-g SVAB and OSB were performed. Cost savings were calculated using nationally allowed flat rates and patient charges. Costs were measured from a hospital and a socioeconomic perspective. Common clinical scenarios and sensitivity analyses assessed the extent of achievable cost savings. 11-g SVAB obviated the need for an OSB in 93 (29%) of 318 women. Overall cost savings per 11-g SVAB over OSB were € 242 per case from a hospital perspective, and € 422 per case from a socioeconomic perspective. The use of 11-g SVAB decreased the cost of diagnosis by 7% from a hospital perspective, and by 10% from a socioeconomic perspective. In Austria, annual national savings of over 5 million Euro could be realized with the use of 11-g SVAB for the diagnosis of suspicious breast lesions. Although savings per case are modest, the national health care system realizes significant cost reduction as women benefit from a faster and less invasive approach to diagnosis. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.
Special treatment reduces helium permeation of glass in vacuum systems
NASA Technical Reports Server (NTRS)
Bryant, P. J.; Gosselin, C. M.
1966-01-01
Internal surfaces of the glass component of a vacuum system are exposed to cesium in gaseous form to reduce helium permeation. The cesium gas is derived from decomposition of cesium nitrate through heating. Several minutes of exposure of the internal surfaces of the glass vessel are sufficient to complete the treatment.
Wafer-Level Vacuum Packaging of Smart Sensors.
Hilton, Allan; Temple, Dorota S
2016-10-31
The reach and impact of the Internet of Things will depend on the availability of low-cost, smart sensors-"low cost" for ubiquitous presence, and "smart" for connectivity and autonomy. By using wafer-level processes not only for the smart sensor fabrication and integration, but also for packaging, we can further greatly reduce the cost of sensor components and systems as well as further decrease their size and weight. This paper reviews the state-of-the-art in the wafer-level vacuum packaging technology of smart sensors. We describe the processes needed to create the wafer-scale vacuum microchambers, focusing on approaches that involve metal seals and that are compatible with the thermal budget of complementary metal-oxide semiconductor (CMOS) integrated circuits. We review choices of seal materials and structures that are available to a device designer, and present techniques used for the fabrication of metal seals on device and window wafers. We also analyze the deposition and activation of thin film getters needed to maintain vacuum in the ultra-small chambers, and the wafer-to-wafer bonding processes that form the hermetic seal. We discuss inherent trade-offs and challenges of each seal material set and the corresponding bonding processes. Finally, we identify areas for further research that could help broaden implementations of the wafer-level vacuum packaging technology.
Vacuum chamber-free centrifuge with magnetic bearings.
Park, Cheol Hoon; Kim, Soohyun; Kim, Kyung-Soo
2013-09-01
Centrifuges are devices that separate particles of different densities and sizes through the application of a centrifugal force. If a centrifuge could be operated under atmospheric conditions, all vacuum-related components such as the vacuum chamber, vacuum pump, diffusion pump, and sealing could be removed from a conventional centrifuge system. The design and manufacturing procedure for centrifuges could then be greatly simplified to facilitate the production of lightweight centrifuge systems of smaller volume. Furthermore, the maintenance costs incurred owing to wear and tear due to conventional ball bearings would be eliminated. In this study, we describe a novel vacuum chamber-free centrifuge supported by magnetic bearings. We demonstrate the feasibility of the vacuum chamber-free centrifuge by presenting experimental results that verify its high-speed support capability and motoring power capacity.
Multipurpose Vacuum Induction Processing System
NASA Astrophysics Data System (ADS)
Govindaraju, M.; Kulkarni, Deepak; Balasubramanian, K.
2012-11-01
Multipurpose vacuum processing systems are cost effective; occupy less space, multiple functional under one roof and user friendly. A multipurpose vacuum induction system was designed, fabricated and installed in a record time of 6 months time at NFTDC Hyderabad. It was designed to function as a) vacuum induction melting/refining of oxygen free electronic copper/pure metals, b) vacuum induction melting furnace for ferrous materials c) vacuum induction melting for non ferrous materials d) large vacuum heat treatment chamber by resistance heating (by detachable coil and hot zone) e) bottom discharge vacuum induction melting system for non ferrous materials f) Induction heat treatment system and g) directional solidification /investment casting. It contains provision for future capacity addition. The attachments require to manufacture multiple shaped castings and continuous rod casting can be added whenever need arises. Present capacity is decided on the requirement for 10years of development path; presently it has 1.2 ton liquid copper handling capacity. It is equipped with provision for capacity addition up to 2 ton liquid copper handling capacity in future. Provision is made to carry out the capacity addition in easy steps quickly. For easy operational maintenance and troubleshooting, design was made in easily detachable sections. High vacuum system is also is detachable, independent and easily movable which is first of its kind in the country. Detailed design parameters, advantages and development history are presented in this paper.
Demonstration of Microsphere Insulation in Cryogenic Vessels
NASA Astrophysics Data System (ADS)
Baumgartner, R. G.; Myers, E. A.; Fesmire, J. E.; Morris, D. L.; Sokalski, E. R.
2006-04-01
While microspheres have been recognized as a legitimate insulation material for decades, actual use in full-scale cryogenic storage tanks has not been demonstrated until now. The performance and life-cycle-cost advantages previously predicted have now been proven. Most bulk cryogenic storage tanks are insulated with either multilayer insulation (MLI) or perlite. Microsphere insulation, consisting of hollow glass bubbles, combines in a single material the desirable properties that other insulations only have individually. The material has high crush strength, low density, is noncombustible, and performs well in soft vacuum. These properties were proven during recent field testing of two 22,700-L (6,000-gallon) liquid nitrogen tanks, one insulated with microsphere insulation and the other with perlite. Normal evaporation rates (NER) for both tanks were monitored with precision test equipment and insulation levels within the tanks were observed through view ports as an indication of insulation compaction. Specific industrial applications were evaluated based on the test results and beneficial properties of microsphere insulation. Over-the-road trailers previously insulated with perlite will benefit not only from the reduced heat leak, but also the reduced mass of microsphere insulation. Economic assessments for microsphere-insulated cryogenic vessels including life-cycle cost are also presented.
Self-contained in-vacuum in situ thin film stress measurement tool
NASA Astrophysics Data System (ADS)
Reinink, J.; van de Kruijs, R. W. E.; Bijkerk, F.
2018-05-01
A fully self-contained in-vacuum device for measuring thin film stress in situ is presented. The stress was measured by measuring the curvature of a cantilever on which the thin film was deposited. For this, a dual beam laser deflectometer was used. All optics and electronics needed to perform the measurement are placed inside a vacuum-compatible vessel with the form factor of the substrate holders of the deposition system used. The stand-alone nature of the setup allows the vessel to be moved inside a deposition system independently of optical or electronic feedthroughs while measuring continuously. A Mo/Si multilayer structure was analyzed to evaluate the performance of the setup. A radius of curvature resolution of 270 km was achieved. This allows small details of the stress development to be resolved, such as the interlayer formation between the layers and the amorphous-to-crystalline transition of the molybdenum which occurs at around 2 nm. The setup communicates with an external computer via a Wi-Fi connection. This wireless connection allows remote control over the acquisition and the live feedback of the measured stress. In principle, the vessel can act as a general metrology platform and add measurement capabilities to deposition setups with no modification to the deposition system.
Venturi vacuum systems for hypobaric chamber operations.
Robinson, R; Swaby, G; Sutton, T; Fife, C; Powell, M; Butler, B D
1997-11-01
Physiological studies of the effects of high altitude on man often require the use of a hypobaric chamber to simulate the reduced ambient pressures. Typical "altitude" chambers in use today require complex mechanical vacuum systems to evacuate the chamber air, either directly or via reservoir system. Use of these pumps adds to the cost of both chamber procurement and maintenance, and service of these pumps requires trained support personnel and regular upkeep. In this report we describe use of venturi vacuum pumps to perform the function of mechanical vacuum pumps for human and experimental altitude chamber operations. Advantages of the venturi pumps include their relatively low procurement cost, small size and light weight, ease of installation and plumbing, lack of moving parts, and independence from electrical power sources, fossil fuels and lubricants. Conversion of three hyperbaric chambers to combined hyper/hypobaric use is described.
Vacuum Studies of a Prototype Composite Coil Dewar for HTSC Transformers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schwenterly, S W; Zhang, Y.; Pleva, Ed
2010-01-01
Oak Ridge National Laboratory (ORNL) is collaborating with Waukesha Electric Systems (WES) to develop a high-temperature superconducting (HTSC) utility power transformer with primary and secondary coils cooled by liquid nitrogen. Since the vacuuminsulated cryogenic coil dewar surrounds the magnetic core limb and cannot form a shorted turn, non-conductive materials are required. Two test vessels and a small prototype dewar have been fabricated by Scorpius Space Launch Company with epoxy/fiberglass composites, using their proprietary PRESSURMAXX vessel technology. The effects of pumping time, bakeout temperature, and cryogenic vessel temperature on vacuum outgassing rates have been investigated. Outgassing rates of the individual materialsmore » used in vessel construction have also been measured. The results will be scaled up to determine the required pumping capacity for a full-size 25-MVA commercial transformer dewar.« less
Vacuum-deposited polymer/silver reflector material
NASA Astrophysics Data System (ADS)
Affinito, John D.; Martin, Peter M.; Gross, Mark E.; Bennett, Wendy D.
1994-09-01
Weatherable, low cost, front surface, solar reflectors on flexible substrates would be highly desirable for lamination to solar concentrator panels. The method to be described in this paper may permit such reflector material to be fabricated for less the 50$CNT per square foot. Vacuum deposited Polymer/Silver/Polymer reflectors and Fabry-Perot interference filters were fabricated in a vacuum web coating operation on polyester substrates. Reflectivities were measured in the wavelength range from .4 micrometers to .8 micrometers . It is hoped that a low cost substrate can be used with the substrate laminated to the concentrator and the weatherable acrylic polymer coating facing the sun. This technique should be capable of deposition line speeds approaching 1500 linear feet/minute2. Central to this technique is a new vacuum deposition process for the high rate deposition of polymer films. This polymer process involves the flash evaporation of an acrylic monomer onto a moving substrate. The monomer is subsequently cured by an electron beam or ultraviolet light. This high speed polymer film deposition process has been named the PML process- for Polymer Multi- Layer.
Static-stress analysis of dual-axis confinement vessel
NASA Astrophysics Data System (ADS)
Bultman, D. H.
1992-11-01
This study evaluates the static-pressure containment capability of a 6-ft-diameter, spherical vessel, made of HSLA-100 steel, to be used for high-explosive (HE) containment. The confinement vessel is designed for use with the Dual-Axis Radiographic Hydrotest Facility (DARHT) being developed at Los Alamos National Laboratory. Two sets of openings in the vessel are covered with x-ray transparent covers to allow radiographic imaging of an explosion as it occurs inside the vessel. The confinement vessel is analyzed as a pressure vessel based on the ASME Boiler and Pressure Vessel Code, Section 8, Division 1, and the Welding Research Council Bulletin, WRC-107. Combined stresses resulting from internal pressure and external loads on nozzles are calculated and compared with the allowable stresses for HSLA-100 steel. Results confirm that the shell and nozzles of the confinement vessel are adequately designed to safely contain the maximum residual pressure of 1675 psi that would result from an HE charge of 24.2 kg detonated in a vacuum. Shell stresses at the shell-to-nozzle interface, produced from external loads on the nozzles, were less than 400 psi. The maximum combined stress resulting from the internal pressure plus external loads was 16,070 psi, which is less than half the allowable stress of 42,375 psi for HSLA-100 steel.
Core Vessel Insert Handling Robot for the Spallation Neutron Source
DOE Office of Scientific and Technical Information (OSTI.GOV)
Graves, Van B; Dayton, Michael J
2011-01-01
The Spallation Neutron Source provides the world's most intense pulsed neutron beams for scientific research and industrial development. Its eighteen neutron beam lines will eventually support up to twenty-four simultaneous experiments. Each beam line consists of various optical components which guide the neutrons to a particular instrument. The optical components nearest the neutron moderators are the core vessel inserts. Located approximately 9 m below the high bay floor, these inserts are bolted to the core vessel chamber and are part of the vacuum boundary. They are in a highly radioactive environment and must periodically be replaced. During initial SNS construction,more » four of the beam lines received Core Vessel Insert plugs rather than functional inserts. Remote replacement of the first Core Vessel Insert plug was recently completed using several pieces of custom-designed tooling, including a highly complicated Core Vessel Insert Robot. The design of this tool are discussed.« less
Main Vacuum Technical Issues of Evacuated Tube Transportation
NASA Astrophysics Data System (ADS)
Zhang, Y. P.; Li, S. S.; Wang, M. X.
In the future, Evacuated Tube Transportation (ETT) would be built and faster than jets. ETT tube with diameter 2∼4m and length over 1000 km will be the largest scale vacuum equipment on earth. This paper listed some main vacuum technical issues to be solved in ETT as follow. How to build ultra-large-scale vacuum chamber like ETT tube with low cost and high reliability? How to pump gas out off the ETT tube in short time? How to release heat or reduce temperature in the vacuum tube? Hot to avoid vacuum electricity discharge? How to manufacture vehicles with airproof shells and equip the life support system? How to detect leakage and find leakage position efficiently and fast as possible? Some relative solutions and suggestions are put up.
Use of Vacuum Degreasing for Precision Cleaning
NASA Technical Reports Server (NTRS)
Fox, Eric; Edwards, Kevin; Mitchell, Mark; Boothe, Richard
2017-01-01
Increasingly strict environmental regulations and the consequent phase out of many effective cleaning solvents has necessitated the development of novel cleaning chemistries and technologies. Among these is vacuum degreasing, a fully enclosed process that eliminates fugitive solvent emissions, thereby reducing cost, environmental, and health related exposure impacts. The effectiveness of vacuum degreasing using modified alcohol for common aerospace contaminants is reported and compared to current and legacy solvents.
Very high-vacuum heat treatment facility
NASA Technical Reports Server (NTRS)
Folkner, W. M.; Moody, M. V.; Richard, J.-P.
1987-01-01
A vacuum heat treatment facility, with hot zone dimensions of 12 x 19 x 19 cm, has been designed and constructed at a cost substantially below that of a commercial unit. The design incorporates efficient water cooling and a resistive heating element. A vacuum pressure of 1.5 x 10 to the -8th torr at room temperature has been obtained after baking. The temperature limit is approximately 1900 C. This limit results from the choice of niobium as the hot zone material.
Vacuum Pump System Optimization Saves Energy at a Dairy Farm
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
In 1998, S&S Dairy optimized the vacuum pumping system at their dairy farm in Modesto, California. In an effort to reduce energy costs, S&S Dairy evaluated their vacuum pumping system to determine if efficiency gains and energy savings were possible.
Takase, Yuta; Tadokoro, Ryosuke; Takahashi, Yoshiko
2013-12-01
To understand how blood vessels form to establish the intricate network during vertebrate development, it is helpful if one can visualize the vasculature in embryos. We here describe a novel labeling method using highlighter ink, easily obtained in stationery stores with a low cost, to visualize embryo-wide vasculatures in avian and mice. We tested 50 different highlighters for fluorescent microscopy with filter sets equipped in a standard fluorescent microscope. The yellow and violet inks yielded fluorescent signals specifically detected by the filters used for green fluorescent protein (GFP) and red fluorescent protein (RFP) detections, respectively. When the ink solution was infused into chicken/quail and mouse embryos, vasculatures including large vessels and capillaries were labeled both in living and fixed embryos. Ink-infused embryos were further subjected to histological sections, and double stained with antibodies including QH-1 (quail), α smooth muscle actin (αSMA), and PECAM-1 (mouse), revealing that the endothelial cells were specifically labeled by the infused highlighter ink. Highlighter-labeled signals were detected with a resolution comparable to or higher than signals of fluorescein isothiocyanate (FITC)-lectin and Rhodamine-dextran, conventionally used for angiography. Furthermore, macroconfocal microscopic analyses with ink-infused embryos visualized fine vascular structures of both embryo proper and extra-embryonic plexus in a Z-stack image of 2400 μm thick with a markedly high resolution. Together, the low cost highlighter ink serves as an alternative reagent useful for visualization of blood vessels in developing avian and mouse embryos and possibly in other animals. © 2013 The Authors Development, Growth & Differentiation © 2013 Japanese Society of Developmental Biologists.
46 CFR 39.20-11 - Vapor overpressure and vacuum protection-TB/ALL.
Code of Federal Regulations, 2012 CFR
2012-10-01
...-11 Section 39.20-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS VAPOR CONTROL SYSTEMS Design and Equipment § 39.20-11 Vapor overpressure and vacuum protection—TB/ALL. (a) The cargo... connected to the vapor collection system does not exceed: (i) The maximum design working pressure for the...
46 CFR 39.20-11 - Vapor overpressure and vacuum protection-TB/ALL.
Code of Federal Regulations, 2011 CFR
2011-10-01
...-11 Section 39.20-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS VAPOR CONTROL SYSTEMS Design and Equipment § 39.20-11 Vapor overpressure and vacuum protection—TB/ALL. (a) The cargo... connected to the vapor collection system does not exceed: (i) The maximum design working pressure for the...
46 CFR 39.20-11 - Vapor overpressure and vacuum protection-TB/ALL.
Code of Federal Regulations, 2010 CFR
2010-10-01
...-11 Section 39.20-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS VAPOR CONTROL SYSTEMS Design and Equipment § 39.20-11 Vapor overpressure and vacuum protection—TB/ALL. (a) The cargo... connected to the vapor collection system does not exceed: (i) The maximum design working pressure for the...
In-vessel visible inspection system on KSTAR
NASA Astrophysics Data System (ADS)
Chung, Jinil; Seo, D. C.
2008-08-01
To monitor the global formation of the initial plasma and damage to the internal structures of the vacuum vessel, an in-vessel visible inspection system has been installed and operated on the Korean superconducting tokamak advanced research (KSTAR) device. It consists of four inspection illuminators and two visible/H-alpha TV cameras. Each illuminator uses four 150W metal-halide lamps with separate lamp controllers, and programmable progressive scan charge-coupled device cameras with 1004×1004 resolution at 48frames/s and a resolution of 640×480 at 210frames/s are used to capture images. In order to provide vessel inspection capability under any operation condition, the lamps and cameras are fully controlled from the main control room and protected by shutters from deposits during plasma operation. In this paper, we describe the design and operation results of the visible inspection system with the images of the KSTAR Ohmic discharges during the first plasma campaign.
Fabricate-On-Demand Vacuum Insulating Glazings
DOE Office of Scientific and Technical Information (OSTI.GOV)
McCamy, James W.
PPG proposed to design a fabricate-on-demand manufacturing process to overcome the cost and supply chain issues preventing widespread adoption of vacuum insulated glazing (VIG) units. To do so, we focused on improving three areas of VIG manufacturing that drive high costs and limit the ability for smaller manufacturers to enter the market: edge sealing, pillar design/placement, and evacuating the VIG.
Window-assisted nanosphere lithography for vacuum micro-nano-electronics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Nannan; Institute of Electronic Engineering, Chinese Academy of Engineering Physics, Mianyang, 621900; Pang, Shucai
2015-04-15
Development of vacuum micro-nano-electronics is quite important for combining the advantages of vacuum tubes and solid-state devices but limited by the prevailing fabricating techniques which are expensive, time consuming and low-throughput. In this work, window-assisted nanosphere lithography (NSL) technique was proposed and enabled the low-cost and high-efficiency fabrication of nanostructures for vacuum micro-nano-electronic devices, thus allowing potential applications in many areas. As a demonstration, we fabricated high-density field emitter arrays which can be used as cold cathodes in vacuum micro-nano-electronic devices by using the window-assisted NSL technique. The details of the fabricating process have been investigated. This work provided amore » new and feasible idea for fabricating nanostructure arrays for vacuum micro-nano-electronic devices, which would spawn the development of vacuum micro-nano-electronics.« less
Cold cathode vacuum gauging system
Denny, Edward C.
2004-03-09
A vacuum gauging system of the cold cathode type is provided for measuring the pressure of a plurality of separate vacuum systems, such as in a gas centrifuge cascade. Each casing is fitted with a gauge tube assembly which communicates with the vacuum system in the centrifuge casing. Each gauge tube contains an anode which may be in the form of a slender rod or wire hoop and a cathode which may be formed by the wall of the gauge tube. The tube is provided with an insulated high voltage connector to the anode which has a terminal for external connection outside the vacuum casing. The tube extends from the casing so that a portable magnet assembly may be inserted about the tube to provide a magnetic field in the area between the anode and cathode necessary for pressure measurements in a cold cathode-type vacuum gauge arrangement. The portable magnetic assembly is provided with a connector which engages the external high voltage terminal for providing power to the anode within in the gauge tube. Measurement is made in the same manner as the prior cold cathode gauges in that the current through the anode to the cathode is measured as an indication of the pressure. By providing the portable magnetic assembly, a considerable savings in cost, installation, and maintenance of vacuum gauges for pressure measurement in a gas centrifuge cascade is realizable.
Wireless Integrated Microelectronic Vacuum Sensor System
NASA Technical Reports Server (NTRS)
Krug, Eric; Philpot, Brian; Trott, Aaron; Lawrence, Shaun
2013-01-01
NASA Stennis Space Center's (SSC's) large rocket engine test facility requires the use of liquid propellants, including the use of cryogenic fluids like liquid hydrogen as fuel, and liquid oxygen as an oxidizer (gases which have been liquefied at very low temperatures). These fluids require special handling, storage, and transfer technology. The biggest problem associated with transferring cryogenic liquids is product loss due to heat transfer. Vacuum jacketed piping is specifically designed to maintain high thermal efficiency so that cryogenic liquids can be transferred with minimal heat transfer. A vacuum jacketed pipe is essentially two pipes in one. There is an inner carrier pipe, in which the cryogenic liquid is actually transferred, and an outer jacket pipe that supports and seals the vacuum insulation, forming the "vacuum jacket." The integrity of the vacuum jacketed transmission lines that transfer the cryogenic fluid from delivery barges to the test stand must be maintained prior to and during engine testing. To monitor the vacuum in these vacuum jacketed transmission lines, vacuum gauge readings are used. At SSC, vacuum gauge measurements are done on a manual rotation basis with two technicians, each using a handheld instrument. Manual collection of vacuum data is labor intensive and uses valuable personnel time. Additionally, there are times when personnel cannot collect the data in a timely fashion (i.e., when a leak is detected, measurements must be taken more often). Additionally, distribution of this data to all interested parties can be cumbersome. To simplify the vacuum-gauge data collection process, automate the data collection, and decrease the labor costs associated with acquiring these measurements, an automated system that monitors the existing gauges was developed by Invocon, Inc. For this project, Invocon developed a Wireless Integrated Microelectronic Vacuum Sensor System (WIMVSS) that provides the ability to gather vacuum
Lightweight cryogenic-compatible pressure vessels for vehicular fuel storage
Aceves, Salvador; Berry, Gene; Weisberg, Andrew H.
2004-03-23
A lightweight, cryogenic-compatible pressure vessel for flexibly storing cryogenic liquid fuels or compressed gas fuels at cryogenic or ambient temperatures. The pressure vessel has an inner pressure container enclosing a fuel storage volume, an outer container surrounding the inner pressure container to form an evacuated space therebetween, and a thermal insulator surrounding the inner pressure container in the evacuated space to inhibit heat transfer. Additionally, vacuum loss from fuel permeation is substantially inhibited in the evacuated space by, for example, lining the container liner with a layer of fuel-impermeable material, capturing the permeated fuel in the evacuated space, or purging the permeated fuel from the evacuated space.
Robust Low Cost Aerospike/RLV Combustion Chamber by Advanced Vacuum Plasma Process
NASA Technical Reports Server (NTRS)
Holmes, Richard; Ellis, David; McKechnie
1999-01-01
Next-generation, regeneratively cooled rocket engines will require materials that can withstand high temperatures while retaining high thermal conductivity. At the same time, fabrication techniques must be cost efficient so that engine components can be manufactured within the constraints of a shrinking NASA budget. In recent years, combustion chambers of equivalent size to the Aerospike chamber have been fabricated at NASA-Marshall Space Flight Center (MSFC) using innovative, relatively low-cost, vacuum-plasma-spray (VPS) techniques. Typically, such combustion chambers are made of the copper alloy NARloy-Z. However, current research and development conducted by NASA-Lewis Research Center (LeRC) has identified a Cu-8Cr-4Nb alloy which possesses excellent high-temperature strength, creep resistance, and low cycle fatigue behavior combined with exceptional thermal stability. In fact, researchers at NASA-LeRC have demonstrated that powder metallurgy (P/M) Cu-8Cr-4Nb exhibits better mechanical properties at 1,200 F than NARloy-Z does at 1,000 F. The objective of this program was to develop and demonstrate the technology to fabricate high-performance, robust, inexpensive combustion chambers for advanced propulsion systems (such as Lockheed-Martin's VentureStar and NASA's Reusable Launch Vehicle, RLV) using the low-cost, VPS process to deposit Cu-8Cr-4Nb with mechanical properties that match or exceed those of P/M Cu-8Cr-4Nb. In addition, oxidation resistant and thermal barrier coatings can be incorporated as an integral part of the hot wall of the liner during the VPS process. Tensile properties of Cu-8Cr-4Nb material produced by VPS are reviewed and compared to material produced previously by extrusion. VPS formed combustion chamber liners have also been prepared and will be reported on following scheduled hot firing tests at NASA-Lewis.
Wafer-Level Vacuum Packaging of Smart Sensors
Hilton, Allan; Temple, Dorota S.
2016-01-01
The reach and impact of the Internet of Things will depend on the availability of low-cost, smart sensors—“low cost” for ubiquitous presence, and “smart” for connectivity and autonomy. By using wafer-level processes not only for the smart sensor fabrication and integration, but also for packaging, we can further greatly reduce the cost of sensor components and systems as well as further decrease their size and weight. This paper reviews the state-of-the-art in the wafer-level vacuum packaging technology of smart sensors. We describe the processes needed to create the wafer-scale vacuum microchambers, focusing on approaches that involve metal seals and that are compatible with the thermal budget of complementary metal-oxide semiconductor (CMOS) integrated circuits. We review choices of seal materials and structures that are available to a device designer, and present techniques used for the fabrication of metal seals on device and window wafers. We also analyze the deposition and activation of thin film getters needed to maintain vacuum in the ultra-small chambers, and the wafer-to-wafer bonding processes that form the hermetic seal. We discuss inherent trade-offs and challenges of each seal material set and the corresponding bonding processes. Finally, we identify areas for further research that could help broaden implementations of the wafer-level vacuum packaging technology. PMID:27809249
Cryogenic Insulation System for Soft Vacuum
NASA Technical Reports Server (NTRS)
Augustynowicz, S. D.; Fesmire, J. E.
1999-01-01
The development of a cryogenic insulation system for operation under soft vacuum is presented in this paper. Conventional insulation materials for cryogenic applications can be divided into three levels of thermal performance, in terms of apparent thermal conductivity [k-value in milliwatt per meter-kelvin (mW/m-K)]. System k-values below 0.1 can be achieved for multilayer insulation operating at a vacuum level below 1 x 10(exp -4) torr. For fiberglass or powder operating below 1 x 10(exp -3) torr, k-values of about 2 are obtained. For foam and other materials at ambient pressure, k-values around 30 are typical. New industry and aerospace applications require a versatile, robust, low-cost thermal insulation with performance in the intermediate range. The target for the new composite insulation system is a k-value below 4.8 mW/m-K (R-30) at a soft vacuum level (from 1 to 10 torr) and boundary temperatures of approximately 77 and 293 kelvin (K). Many combinations of radiation shields, spacers, and composite materials were tested from high vacuum to ambient pressure using cryostat boiloff methods. Significant improvement over conventional systems in the soft vacuum range was demonstrated. The new layered composite insulation system was also shown to provide key benefits for high vacuum applications as well.
NASA Astrophysics Data System (ADS)
Han, Yongquan
2015-03-01
To study on vacuum force, we must clear what is vacuum, vacuum is a space do not have any air and also ray. There is not exist an absolute the vacuum of space. The vacuum of space is relative, so that the vacuum force is relative. There is a certain that vacuum vacuum space exists. In fact, the vacuum space is relative, if the two spaces compared to the existence of relative vacuum, there must exist a vacuum force, and the direction of the vacuum force point to the vacuum region. Any object rotates and radiates. Rotate bend radiate- centripetal, gravity produced, relative gravity; non gravity is the vacuum force. Gravity is centripetal, is a trend that the objects who attracted wants to Centripetal, or have been do Centripetal movement. Any object moves, so gravity makes the object curve movement, that is to say, the radiation range curve movement must be in the gravitational objects, gravity must be existed in non vacuum region, and make the object who is in the region of do curve movement (for example: The earth moves around the sun), or final attracted in the form gravitational objects, and keep relatively static with attract object. (for example: objects on the earth moves but can't reach the first cosmic speed).
Steam ejector-condenser: stage I of a differential vacuum pumping station
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanson, C.L.; Alger, T.W.
1981-04-01
A steam ejector-condenser unit was built and tested to produce a 10 Torr (13.3 x 10/sup 2/Pa) vacuum with a 2 cm aperture to the atmosphere. This unit is the first stage of a differential vacuum pumping station that will be used with the Experimental Test Accelerator. The accelerator's electron beam will pass through a series of openings from a high vacuum (5 x 10/sup -6/ Torr) to the atmosphere. The differential system consists of four vacuum pumping units separated by 2 cm-diam apertures. Superheated steam is injected near the final beamline orifice to reduce the quantity of atmospheric airmore » flowing into the steam ejector--condenser unit. The steam ejector in the condenser vessel is open at its center to permit passage of the accelerator beam. Five nozzles mounted in a conical array produce the ejector vacuum of 10 Torr. The ejector exhausts into the condenser and forms a barrier to air flow into the lower pressure region. This feature permits high volume cold trapping and cryopumping of water vapor in the remaining lower-pressure stages. Tests have proven that the steam ejector--condenser is a reliable operating unit and suitable for long-term, steady-state accelerator operation.« less
Lung vessel segmentation in CT images using graph-cuts
NASA Astrophysics Data System (ADS)
Zhai, Zhiwei; Staring, Marius; Stoel, Berend C.
2016-03-01
Accurate lung vessel segmentation is an important operation for lung CT analysis. Filters that are based on analyzing the eigenvalues of the Hessian matrix are popular for pulmonary vessel enhancement. However, due to their low response at vessel bifurcations and vessel boundaries, extracting lung vessels by thresholding the vesselness is not sufficiently accurate. Some methods turn to graph-cuts for more accurate segmentation, as it incorporates neighbourhood information. In this work, we propose a new graph-cuts cost function combining appearance and shape, where CT intensity represents appearance and vesselness from a Hessian-based filter represents shape. Due to the amount of voxels in high resolution CT scans, the memory requirement and time consumption for building a graph structure is very high. In order to make the graph representation computationally tractable, those voxels that are considered clearly background are removed from the graph nodes, using a threshold on the vesselness map. The graph structure is then established based on the remaining voxel nodes, source/sink nodes and the neighbourhood relationship of the remaining voxels. Vessels are segmented by minimizing the energy cost function with the graph-cuts optimization framework. We optimized the parameters used in the graph-cuts cost function and evaluated the proposed method with two manually labeled sub-volumes. For independent evaluation, we used 20 CT scans of the VESSEL12 challenge. The evaluation results of the sub-volume data show that the proposed method produced a more accurate vessel segmentation compared to the previous methods, with F1 score 0.76 and 0.69. In the VESSEL12 data-set, our method obtained a competitive performance with an area under the ROC curve of 0.975, especially among the binary submissions.
Commercial Vessel Safety. Economic Costs. Preliminary.
1979-12-01
or "rippled" through the economy when a regulation is implemented. The survey associated with determination of costs focused upon two basic areas...in their application of standard financial principles and in their utilization of basic ship cost components (e.g., investment and operating costs...on the estimation of costs per ton of capacity provided. The basic unit for analyzing ships’ costs used is a single voyage (round trip) on a particular
Design of large vacuum chamber for VEC superconducting cyclotron beam line switching magnet
NASA Astrophysics Data System (ADS)
Bhattacharya, Sumantra; Nandi, Chinmoy; Gayen, Subhasis; Roy, Suvadeep; Mishra, Santosh Kumar; Ramrao Bajirao, Sanjay; Pal, Gautam; Mallik, C.
2012-11-01
VEC K500 superconducting cyclotron will be used to accelerate heavy ion. The accelerated beam will be transported to different beam halls by using large switching magnets. The vacuum chamber for the switching magnet is around 1000 mm long. It has a height of 85 mm and width varying from 100 mm to 360 mm. The material for the chamber has been chosen as SS304.The material for the vacuum chamber for the switching magnet has been chosen as SS304. Design of the vessel was done as per ASME Boiler and Pressure Vessel Code, Section VIII, Division 1. It was observed that primary stress values exceed the allowable limit. Since, the magnet was already designed with a fixed pole gap; increase of the vacuum chamber plate thickness restricts the space for beam transport. Design was optimized using stress analysis software ANSYS. Analysis was started using plate thickness of 4 mm. The stress was found higher than the allowable level. The analysis was repeated by increasing plate thickness to 6 mm, resulting in the reduction of stress level below the allowable level. In order to reduce the stress concentration due to sharp bend, chamfering was done at the corner, where the stress level was higher. The thickness of the plate at the corner was increased from 6 mm to 10 mm. These measures resulted in reduction of localized stress.
NASA Astrophysics Data System (ADS)
Bhattachryya, Pranab; Gupta, Anjan Dutta; Dhar, S.; Sarma, P. R.; Mukherjee, Paramita
2017-06-01
The helium vessel of the superconducting cyclotron (SCC) at the Variable Energy Cyclotron centre (VECC), Kolkata shows a gradual loss of insulation vacuum from 10-7 mbar to 10-4 mbar with increasing coil current in the magnet. The insulation vacuum restores back to its initial value with the withdrawal of current. The origin of such behavior has been thought to be related to the electromagnetic stress in the magnet. The electromagnetic stress distribution in the median plane of the helium vessel was studied to figure out the possible location of the helium leak. The stress field from the possible location was transferred to a simplified 2D model with different leak geometries to study the changes in conductance with coil current. The leak rate calculated from the changes in the leak geometry was compared with the leak rate calculated from the experimental insulation vacuum degradation behavior to estimate the initial leak shape and size.
The proposal of recommendations for the operation of vacuum sewerage
NASA Astrophysics Data System (ADS)
Mazák, J.; Dvorský, T.; Václavík, V.; Zajac, R.; Hluštík, P.
2017-10-01
This article deals with a comparison of vacuum sewerage system and gravity based sewerage system. It also includes the results of the comparison of both of these systems from various cities, and there are measures suggested on the basis of the findings focused on increasing the efficiency and reducing the operational costs of the selected vacuum sewerage system.
Code of Federal Regulations, 2010 CFR
2010-04-01
...., vessels equipped with automated self- unloading conveyor belts or vacuum-actuated systems) to use alien...) With intent or design to influence an election of a bargaining representative for workers at the U.S...
Robust Low Cost Liquid Rocket Combustion Chamber by Advanced Vacuum Plasma Process
NASA Technical Reports Server (NTRS)
Holmes, Richard; Elam, Sandra; Ellis, David L.; McKechnie, Timothy; Hickman, Robert; Rose, M. Franklin (Technical Monitor)
2001-01-01
Next-generation, regeneratively cooled rocket engines will require materials that can withstand high temperatures while retaining high thermal conductivity. Fabrication techniques must be cost efficient so that engine components can be manufactured within the constraints of shrinking budgets. Three technologies have been combined to produce an advanced liquid rocket engine combustion chamber at NASA-Marshall Space Flight Center (MSFC) using relatively low-cost, vacuum-plasma-spray (VPS) techniques. Copper alloy NARloy-Z was replaced with a new high performance Cu-8Cr-4Nb alloy developed by NASA-Glenn Research Center (GRC), which possesses excellent high-temperature strength, creep resistance, and low cycle fatigue behavior combined with exceptional thermal stability. Functional gradient technology, developed building composite cartridges for space furnaces was incorporated to add oxidation resistant and thermal barrier coatings as an integral part of the hot wall of the liner during the VPS process. NiCrAlY, utilized to produce durable protective coating for the space shuttle high pressure fuel turbopump (BPFTP) turbine blades, was used as the functional gradient material coating (FGM). The FGM not only serves as a protection from oxidation or blanching, the main cause of engine failure, but also serves as a thermal barrier because of its lower thermal conductivity, reducing the temperature of the combustion liner 200 F, from 1000 F to 800 F producing longer life. The objective of this program was to develop and demonstrate the technology to fabricate high-performance, robust, inexpensive combustion chambers for advanced propulsion systems (such as Lockheed-Martin's VentureStar and NASA's Reusable Launch Vehicle, RLV) using the low-cost VPS process. VPS formed combustion chamber test articles have been formed with the FGM hot wall built in and hot fire tested, demonstrating for the first time a coating that will remain intact through the hot firing test, and with
Space environmental considerations for a long-term cryogenic storage vessel
NASA Technical Reports Server (NTRS)
Nakanishi, Shigeo
1987-01-01
Information is given on the kind of protection that is needed against impact and perforation of a long-term cryogenic storage vessel in space by meteoroids and space debris. The long-term effects of the space environment on thermal control surfaces and coatings, and the question of whether the insulation and thermal control surfaces should be encased in a vacuum jacket shell are discussed.
78 FR 14053 - Vessel Documentation Renewal Fees
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-04
... fee of $26 per documented vessel. This proposed rule impacts a diverse set of industry sectors with a wide range of fleet sizes and revenues. Table 4 provides example data for three affected small..., Vessel Count, and Cost for Three Affected Small Entities Small entity Small entity Category representing...
ERIC Educational Resources Information Center
Young, Edmond W. K.; Simmons, Craig A.
2009-01-01
We describe a simple, low-cost laboratory session to demonstrate the Fahraeus-Lindqvist effect, a microphase flow phenomenon that occurs in small blood vessels and alters the effective rheological properties of blood. The experiments are performed by flowing cells through microchannels fabricated by soft lithography and characterization of cell…
Isolated Bacterial Spores at High-velocity Survive Surface Impacts in Vacuum
NASA Astrophysics Data System (ADS)
Austin, Daniel; Barney, Brandon
We present experiments in which bacterial spores were found to survive being accelerated in vacuum to velocities in the range 30-120 m/s and impacted on a dense target. In these experiments, spores of Bacillus subtilis spores were charged using electrospray at atmospheric pressure, dried, and then introduced into high vacuum. Through choice of skimmers and beam tubes, different velocity ranges were achieved. An image-charge detector observed the charged spores, providing total charge and velocity. The spores then impacted a glass target within a collection vessel. After the experiment, the collection vessel contents were extracted and cultured. Several positive and negative controls were used, including the use of antibiotic-resistant spores and antibiotic-containing (rifampicin) agar for culturing. These impact velocities are of particular interest for possible transport of bacterial spores from Mars to Phobos, and may have implications for planetary protection in a Phobos sample return mission. In addition, bacteria may reach similar velocities during a spacecraft crash (e.g., within components, or from spacecraft to surface materials during impact, etc.), raising concerns about forward contamination. The velocities of interest to transport of life between planets (panspermia) are somewhat higher, but these results complement shock-based experiments and contribute to the general discussion of impact survivability of organisms.
Tubing vs. buckets: a cost comparison
Neil K. Huyler
1975-01-01
Equipment investment for tubing-vacuum systems was significantly less than that for bucket systems. Tubing-vacuum systems required about 22 percent less labor input, the major labor input being completed before sap-flow periods. Annual cost of operation was less for tubing-vacuum than the bucket system. Small tubing-vacuum operations showed more profit potential than...
Aluminum and Other Coatings for the Passivation of Tritium Storage Vessels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spencer, W.; Korinko, P.
. All of the studies indicated that vessels needed several days of vacuum baking at 350-450° C to fully outgas the residual gases, which were mostly hydrogen. The current standard practice of out-gassing from ultra-clean, electro-polished 304L vessels with both vacuum bake-out and followed by an oxidative bake out to enhance the chromium surface performed the best in these studies.« less
True random numbers from amplified quantum vacuum.
Jofre, M; Curty, M; Steinlechner, F; Anzolin, G; Torres, J P; Mitchell, M W; Pruneri, V
2011-10-10
Random numbers are essential for applications ranging from secure communications to numerical simulation and quantitative finance. Algorithms can rapidly produce pseudo-random outcomes, series of numbers that mimic most properties of true random numbers while quantum random number generators (QRNGs) exploit intrinsic quantum randomness to produce true random numbers. Single-photon QRNGs are conceptually simple but produce few random bits per detection. In contrast, vacuum fluctuations are a vast resource for QRNGs: they are broad-band and thus can encode many random bits per second. Direct recording of vacuum fluctuations is possible, but requires shot-noise-limited detectors, at the cost of bandwidth. We demonstrate efficient conversion of vacuum fluctuations to true random bits using optical amplification of vacuum and interferometry. Using commercially-available optical components we demonstrate a QRNG at a bit rate of 1.11 Gbps. The proposed scheme has the potential to be extended to 10 Gbps and even up to 100 Gbps by taking advantage of high speed modulation sources and detectors for optical fiber telecommunication devices.
Development of in-vessel components of the microfission chamber for ITER.
Ishikawa, M; Kondoh, T; Ookawa, K; Fujita, K; Yamauchi, M; Hayakawa, A; Nishitani, T; Kusama, Y
2010-10-01
Microfission chambers (MFCs) will measure the total neutron source strength in ITER. The MFCs will be installed behind blanket modules in the vacuum vessel (VV). Triaxial mineral insulated (MI) cables will carry signals from the MFCs. The joint connecting triaxial MI cables in the VV must be considered because the MFCs and the MI cables will be installed separately at different times. Vacuum tight triaxial connector of the MI cable has been designed and a prototype has been constructed. Performance tests indicate that the connector can be applied to the ITER environment. A small bending-radius test of the MI cable indicates no observed damage at a curvature radius of 100 mm.
Low-cost insulation system for cryostats eliminates need for a vacuum
NASA Technical Reports Server (NTRS)
Calvert, H. F.
1964-01-01
In order to eliminate the hazard caused by residual air trapped between the concentric shells of a cryostat, these annular spaces are pressurized with helium gas. This system is more economical than the use of powdered insulation maintained at low vacuums.
33 CFR 154.2103 - Facility requirements for vessel vapor overpressure and vacuum protection.
Code of Federal Regulations, 2014 CFR
2014-07-01
... HAZARDOUS MATERIAL IN BULK Marine Vapor Control Systems Transfer Facilities-Vcs Design and Installation... rate, unless there is experimental data for actual vapor growth for turbulent transferring under the... vapor growth. (b) A facility VCS must be designed to prevent the pressure in a vessel's cargo tanks from...
Indian Vacuum Society: The Indian Vacuum Society
NASA Astrophysics Data System (ADS)
Saha, T. K.
2008-03-01
The Indian Vacuum Society (IVS) was established in 1970. It has over 800 members including many from Industry and R & D Institutions spread throughout India. The society has an active chapter at Kolkata. The society was formed with the main aim to promote, encourage and develop the growth of Vacuum Science, Techniques and Applications in India. In order to achieve this aim it has conducted a number of short term courses at graduate and technician levels on vacuum science and technology on topics ranging from low vacuum to ultrahigh vacuum So far it has conducted 39 such courses at different parts of the country and imparted training to more than 1200 persons in the field. Some of these courses were in-plant training courses conducted on the premises of the establishment and designed to take care of the special needs of the establishment. IVS also regularly conducts national and international seminars and symposia on vacuum science and technology with special emphasis on some theme related to applications of vacuum. A large number of delegates from all over India take part in the deliberations of such seminars and symposia and present their work. IVS also arranges technical visits to different industries and research institutes. The society also helped in the UNESCO sponsored post-graduate level courses in vacuum science, technology and applications conducted by Mumbai University. The society has also designed a certificate and diploma course for graduate level students studying vacuum science and technology and has submitted a syllabus to the academic council of the University of Mumbai for their approval, we hope that some colleges affiliated to the university will start this course from the coming academic year. IVS extended its support in standardizing many of the vacuum instruments and played a vital role in helping to set up a Regional Testing Centre along with BARC. As part of the development of vacuum education, the society arranges the participation of
33 CFR 154.814 - Facility requirements for vessel vapor overpressure and vacuum protection.
Code of Federal Regulations, 2013 CFR
2013-07-01
... vapor at a rate of not less than 1.25 times the facility's maximum liquid transfer rate for cargo for... GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION FACILITIES TRANSFERRING OIL OR HAZARDOUS... in the vessel's cargo tanks within this range at any cargo transfer rate less than or equal to the...
Commissioning of the vacuum system of the KATRIN Main Spectrometer
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arenz, M.; Babutzka, M.; Bahr, M.
The KATRIN experiment will probe the neutrino mass by measuring the β-electron energy spectrum near the endpoint of tritium β-decay. We performed an integral energy analysis by an electro-static spectrometer (``Main Spectrometer''), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m 3, and a complex inner electrode system with about 120 000 individual parts. The strong magnetic field that guides the β-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. Furthermore, a system consisting of 6 turbo-molecular pumps andmore » 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300 °C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10 -11 mbar range. We demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.« less
Commissioning of the vacuum system of the KATRIN Main Spectrometer
Arenz, M.; Babutzka, M.; Bahr, M.; ...
2016-04-07
The KATRIN experiment will probe the neutrino mass by measuring the β-electron energy spectrum near the endpoint of tritium β-decay. We performed an integral energy analysis by an electro-static spectrometer (``Main Spectrometer''), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m 3, and a complex inner electrode system with about 120 000 individual parts. The strong magnetic field that guides the β-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. Furthermore, a system consisting of 6 turbo-molecular pumps andmore » 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300 °C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10 -11 mbar range. We demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.« less
The vacuum system reform and test of the super-critical 600mw unit
NASA Astrophysics Data System (ADS)
Yan, Tao; Wan, Zhonghai; Lu, Jin; Chen, Wen; Cai, Wen
2017-11-01
The deficiencies of the designed vacuum system of the super-critical unit is pointed out in this paper, and then it is reformed by the steam ejector. The experimental results show that the vacuum of the condenser can be improved, the coal consumption can be reduced and the plant electricity consumption can be lowered dramatically at a small cost of the steam energy consumption. Meanwhile, the water-ring vacuum pumps cavitation problems can be solved.
Evaluation of Vacuum Blasting and Heat Guns as Methods for Abating Lead- Based Paint on Buildings
1993-09-01
INCOMPATIBILITY - Contact with powerful oxidizing agents such as FLUORINE, CHLORINE TRIFLUORIDE , MANGANESE TRIOXIDE, OXYGEN DIFLUORIDE, MANGANESE...investigating new technologies for lead-based paint abatement. This research evaluates the effectiveness , safety, LEC1L•.T• and cost of vacuum abrasive...paint abatement. This research evaluates the effectiveness , safety, and cost of vacuum abrasive units and heat guns as methods of removing lead-based
Upgrade of The Thermal Vacuum Data System at NASA/GSFC
NASA Technical Reports Server (NTRS)
Palmer, John; Powers, Edward I. (Technical Monitor)
2000-01-01
The Goddard Space Flight Center's new thermal vacuum data acquisition system is a networked client-sever application that enables lab operations crews to monitor all tests from a central location. The GSFC thermal vacuum lab consists of eleven chambers in Building 7 and one chamber in Building 10. The new data system was implemented for several reasons. These included the need for centralized data collection, more flexible and easier to use operator interface, greater data accessibility, a reduction in testing time and cost, and increased payload and personnel safety. Additionally, a new data system was needed for year-2000 compliance. This paper discusses the incorporation of the Thermal Vacuum Data System (TVDS) within the thermal vacuum lab at GSFC, its features and capabilities and lessons learned in its implementation. Additional topics include off-center (Internet) capability for remote monitoring and the role of TVDS in the efforts to automate thermal vacuum chamber operations.
Upgrade of the Thermal Vacuum Data System at NASA/GSFC
NASA Technical Reports Server (NTRS)
Palmer, John
2000-01-01
The Goddard Space Flight Center's new thermal vacuum data acquisition system is a networked client-sever application that enables lab operations crews to monitor all tests from a central location. The GSFC thermal vacuum lab consists of eleven chambers in Building 7 and one chamber in Building 10. The new data system was implemented for several reasons. These included the need for centralized data collection, more flexible and easier to use operator interface, greater data accessibility, a reduction in testing time and cost, and increased payload and personnel safety. Additionally, a new data system was needed for year-2000 compliance. This paper discusses the incorporation of the Thermal Vacuum Data System (TVDS) within the thermal vacuum lab at GSFC, its features and capabilities and lessons learned in its implementation. Additional topics include off-center (Internet) capability for remote monitoring and the role of TVDS in the efforts to automate thermal vacuum chamber operations.
NASA Astrophysics Data System (ADS)
Dalesandro, Andrew A.; Theilacker, Jay; Van Sciver, Steven
2012-06-01
Safe operation of superconducting radio frequency (SRF) cavities require design consideration of a sudden catastrophic loss of vacuum (SCLV) adjacent with liquid helium (LHe) vessels and subsequent dangers. An experiment is discussed to test the longitudinal effects of SCLV along the beam line of a string of scaled SRF cavities. Each scaled cavity includes one segment of beam tube within a LHe vessel containing 2 K saturated LHe, and a riser pipe connecting the LHe vessel to a common gas header. At the beam tube inlet is a fast acting solenoid valve to simulate SCLV and a high/low range orifice plate flow-meter to measure air influx to the cavity. The gas header exit also has an orifice plate flow-meter to measure helium venting the system at the relief pressure of 0.4 MPa. Each cavity is instrumented with Validyne pressure transducers and Cernox thermometers. The purpose of this experiment is to quantify the time required to spoil the beam vacuum and the effects of transient heat and mass transfer on the helium system. Heat transfer data is expected to reveal a longitudinal effect due to the geometry of the experiment. Details of the experimental design criteria and objectives are presented.
Development of in-vessel components of the microfission chamber for ITER1
Ishikawa, M.; Kondoh, T.; Ookawa, K.; Fujita, K.; Yamauchi, M.; Hayakawa, A.; Nishitani, T.; Kusama, Y.
2010-01-01
Microfission chambers (MFCs) will measure the total neutron source strength in ITER. The MFCs will be installed behind blanket modules in the vacuum vessel (VV). Triaxial mineral insulated (MI) cables will carry signals from the MFCs. The joint connecting triaxial MI cables in the VV must be considered because the MFCs and the MI cables will be installed separately at different times. Vacuum tight triaxial connector of the MI cable has been designed and a prototype has been constructed. Performance tests indicate that the connector can be applied to the ITER environment. A small bending-radius test of the MI cable indicates no observed damage at a curvature radius of 100 mm. PMID:21033834
Vacuum system design and tritium inventory for the TFTR charge exchange diagnostic
DOE Office of Scientific and Technical Information (OSTI.GOV)
Medley, S.S.
The charge exchange diagnostic for the TFTR is comprised of two analyzer systems which contain a total of twenty independent mass/energy analyzers and one diagnostic neutral beam tentatively rated at 80 keV, 15 A. The associated vacuum systems were analyzed using the Vacuum System Transient Simulator (VSTS) computer program which models the transient transport of multi-gas species through complex networks of ducts, valves, traps, vacuum pumps, and other related vacuum system components. In addition to providing improved design performance at reduced cost, the analysis yields estimates for the exchange of tritium from the torus to the diagnostic components and ofmore » the diagnostic working gases to the torus.« less
Dynamic Cost Risk Assessment for Controlling the Cost of Naval Vessels
2008-04-23
for each individual RRA at the start of the project are depicted in Figures 2a and 2b, respectively. The PDFs are multimodal and cannot be...underestimates cost. 7 Probabilistic cost analysis A physician metaphor Adapted from Yacov Y. Haimes, NPS 2007 8 Dynamic cost risk management A physician... metaphor Adapted from Yacov Y. Haimes, NPS 2007 9 Sources of cost uncertainty Macroscopic analysis Economic, Materials & Labor, Learning rates
NASA Technical Reports Server (NTRS)
Hackwood, Susan; Belinski, Steven E.; Beni, Gerardo
1989-01-01
The discipline of vacuum mechatronics is defined as the design and development of vacuum-compatible computer-controlled mechanisms for manipulating, sensing and testing in a vacuum environment. The importance of vacuum mechatronics is growing with an increased application of vacuum in space studies and in manufacturing for material processing, medicine, microelectronics, emission studies, lyophylisation, freeze drying and packaging. The quickly developing field of vacuum mechatronics will also be the driving force for the realization of an advanced era of totally enclosed clean manufacturing cells. High technology manufacturing has increasingly demanding requirements for precision manipulation, in situ process monitoring and contamination-free environments. To remove the contamination problems associated with human workers, the tendency in many manufacturing processes is to move towards total automation. This will become a requirement in the near future for e.g., microelectronics manufacturing. Automation in ultra-clean manufacturing environments is evolving into the concept of self-contained and fully enclosed manufacturing. A Self Contained Automated Robotic Factory (SCARF) is being developed as a flexible research facility for totally enclosed manufacturing. The construction and successful operation of a SCARF will provide a novel, flexible, self-contained, clean, vacuum manufacturing environment. SCARF also requires very high reliability and intelligent control. The trends in vacuum mechatronics and some of the key research issues are reviewed.
NASA Technical Reports Server (NTRS)
Leggett, Nickolaus
1990-01-01
The ambient natural vacuum of space is proposed as a basis for electron valves. Each valve is an electron controlling structure similiar to a vacuum tube that is operated without a vacuum sustaining envelope. The natural vacuum electron valves discussed offer a viable substitute for solid state devices. The natural vacuum valve is highly resistant to ionizing radiation, system generated electromagnetic pulse, current transients, and direct exposure to space conditions.
Vacuum forming of thermoplastic sheet results in low-cost investment casting patterns
NASA Technical Reports Server (NTRS)
Clarke, A. E., Jr.
1964-01-01
Vacuum forming of a sheet of thermoplastic material around a mandrel conforming to the shape of the finished object provides a pattern for an investment mold. The thickness of the metal part is determined by the thickness of the plastic pattern.
Gordon, H.S.
1959-09-15
An improved adsorption vacuum trap for use in vacuum systems was designed. The distinguishing feature is the placement of a plurality of torsionally deformed metallic fins within a vacuum jacket extending from the walls to the central axis so that substantially all gas molecules pass through the jacket will impinge upon the fin surfaces. T fins are heated by direct metallic conduction, thereby ol taining a uniform temperature at the adeorbing surfaces so that essentially all of the condensible impurities from the evacuating gas are removed from the vacuum system.
Low Cost Processing of Commingled Thermoplastic Composites
NASA Astrophysics Data System (ADS)
Chiasson, Matthew Lee
A low cost vacuum consolidation process has been investigated for use with commingled thermoplastic matrix composites. In particular, the vacuum consolidation behaviour of commingled polypropylene/glass fibre and commingled nylon/carbon fibre precursors were studied. Laminates were consolidated in a convection oven under vacuum pressure. During processing, the consolidation of the laminate packs was measured by use of non-contact eddy current sensors. The consolidation curves are then used to tune an empirical consolidation model. The overall quality of the resulting laminates is also discussed. Dynamic mechanical analysis, differential scanning calorimetry and mechanical tensile testing were also performed in order to determine the effects of varying processing parameters on the physical and mechanical properties of the laminates. Through this analysis, it was determined that the nylon/carbon fibre blend was not suitable for vacuum consolidation, while the polypropylene/glass fibre blend is a viable option for vacuum consolidation. The ultimate goal of this work is to provide a foundation from which low cost unmanned aerial vehicle (UAV) components can be designed and manufactured from thermoplastic matrix composites using a low cost processing technique as an alternative to traditional thermoset composite materials.
Development of FB-MultiPier dynamic vessel-collision analysis models, phase 2 : [summary].
DOT National Transportation Integrated Search
2014-07-01
When collisions between large vessels and bridge : supports occur, they can result in significant : damage to bridge and vessel. These collisions : are extremely hazardous, often taking lives on : the vessel and the bridge. Direct costs of repair : a...
NASA Technical Reports Server (NTRS)
Selcuk, M. K.
1976-01-01
A solar heat collection system employing non-tracking reflectors integrated with a fixed vacuum tube receiver which achieves modest year-round concentration (about 2) of the sunlight at low capital costs is discussed. The axis of the vee-trough reflector lies in a east-west direction and requires reversal of the reflector surfaces only twice a year without disturbing the receiver tubes and associated plumbing. It collects most of the diffuse flux. The vacuum tube receiver with selective absorber has no convection losses while radiation and conduction losses are minimal. Significant cost reductions are offered since the vee-trough can be fabricated from inexpensive polished or plastic reflector laminated sheet metal covering 2/3 of the collection area, and only about 1/3 of the area is covered with the more expensive vacuum tube receivers. Thermal and economic performance of the vee-trough vacuum tube system, year-round variation of the concentration factor, incident flux, useful heat per unit area at various operation temperatures and energy cost estimates are presented. The electrical energy cost is estimated to be 77 mills/kWh, and the system construction cost is estimated to be $1140/kWe.
Varela, P; Belo, J H; Quental, P B
2016-11-01
The design of the in-vessel antennas for the ITER plasma position reflectometry diagnostic is very challenging due to the need to cope both with the space restrictions inside the vacuum vessel and with the high mechanical and thermal loads during ITER operation. Here, we present the work carried out to assess and optimise the design of the antenna. We show that the blanket modules surrounding the antenna strongly modify its characteristics and need to be considered from the early phases of the design. We also show that it is possible to optimise the antenna performance, within the design restrictions.
Accelerator Vacuum Protection System
NASA Astrophysics Data System (ADS)
Barua, Pradip; Kothari, Ashok; Archunan, M.; Joshi, Rajan
2012-11-01
A new and elaborate automatic vacuum protection system using fast acting valve has been installed to avoid accidental venting of accelerator from experimental chamber side. To cover all the beam lines and to reduce the system cost, it has been installed at a common point from where all the seven beam lines originate. The signals are obtained by placing fast response pressure sensing gauges (HV SENSOR) near all the experimental stations. The closing time of the fast valve is 10 milli-second. The fast closing system protects only one vacuum line at a time. At IUAC, we have seven beam lines so one sensor was placed in each of the beam lines near experimental chamber and a multiplexer was incorporated into the fast closing system. At the time of experiment, the sensor of the active beam line is selected through the multiplexer and the Fast closing valve is interlocked with the selected sensor. As soon as the pressure sensor senses the pressure rise beyond a selected pressure, the signal is transferred and the fast valve closes within 10 to 12 millisecond.
Ultra high vacuum broad band high power microwave window
Nguyen-Tuong, V.; Dylla, H.F. III
1997-11-04
An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost. 5 figs.
Ultra high vacuum broad band high power microwave window
Nguyen-Tuong, Viet; Dylla, III, Henry Frederick
1997-01-01
An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost.
Thermal/vacuum measurements of the Herschel space telescope by close-range photogrammetry
NASA Astrophysics Data System (ADS)
Parian, J. Amiri; Cozzani, A.; Appolloni, M.; Casarosa, G.
2017-11-01
In the frame of the development of a videogrammetric system to be used in thermal vacuum chambers at the European Space Research and Technology Centre (ESTEC) and other sites across Europe, the design of a network using micro-cameras was specified by the European Space agency (ESA)-ESTEC. The selected test set-up is the photogrammetric test of the Herschel Satellite Flight Model in the ESTEC Large Space Simulator. The photogrammetric system will be used to verify the Herschel Telescope alignment and Telescope positioning with respect to the Cryostat Vacuum Vessel (CVV) inside the Large Space Simulator during Thermal-Vacuum/Thermal-Balance test phases. We designed a close-range photogrammetric network by heuristic simulation and a videogrammetric system with an overall accuracy of 1:100,000. A semi-automated image acquisition system, which is able to work at low temperatures (-170°C) in order to acquire images according to the designed network has been constructed by ESA-ESTEC. In this paper we will present the videogrammetric system and sub-systems and the results of real measurements with a representative setup similar to the set-up of Herschel spacecraft which was realized in ESTEC Test Centre.
NASA Astrophysics Data System (ADS)
McGillivary, P. A.; Borges de Sousa, J.; Martins, R.; Rajan, K.
2012-12-01
use of UAS on oceanographic research vessels is just beginning. We report on several initial field efforts which demonstrated that UAS improve spatial and temporal mapping of ocean features, as well as monitoring marine mammal populations, ocean color, sea ice and wave fields and air-sea gas exchange. These studies however also confirm the challenges for shipboard computer systems ingesting and archiving UAS high resolution video, SAR and lidar data. We describe the successful inclusion of DTN communications for: 1) passing video data between two UAS or a UAS and ship; 2) for inclusion of ASVs as communication nodes for AUVs; as well as, 3) enabling extension of adaptive sampling software from AUVs and ASVs to include UAS. In conclusion, we describe how autonomous sampling systems may be best integrated into shipboard oceanographic vessel research to provide new and more comprehensive time-space ocean and atmospheric data collection that is important not only for scientific study, but also for sustainable ocean management, including emergency response capabilities. The recent examples of such integrated studies highlighted confirm ocean and atmospheric studies can more cost-effectively pursued, and in some cases only accomplished, by combining underwater, surface and aircraft autonomous systems with research vessel operations.
Comparison of vacuum and non-vacuum urine tubes for urinary sediment analysis.
Topcuoglu, Canan; Sezer, Sevilay; Kosem, Arzu; Ercan, Mujgan; Turhan, Turan
2017-12-01
Urine collection systems with aspiration system for vacuum tubes are becoming increasingly common for urinalysis, especially for microscopic examination of the urine. In this study, we aimed to examine whether vacuum aspiration of the urine sample has any adverse effect on sediment analysis by comparing results from vacuum and non-vacuum urine tubes. The study included totally 213 urine samples obtained from inpatients and outpatients in our hospital. Urine samples were collected to containers with aspiration system for vacuum tubes. Each sample was aliquoted to both vacuum and non-vacuum urine tubes. Urinary sediment analysis was performed using manual microscope. Results were evaluated using chi-square test. Comparison of the sediment analysis results from vacuum and non-vacuum urine tubes showed that results were highly concordant for erythrocyte, leukocyte and epithelial cells (gamma values 1, 0.997, and 0.994, respectively; p < .001). Results were also concordant for urinary casts, crystals and yeast (kappa values 0.815, 0.945 and 1, respectively; p < .001). The results show that in urinary sediment analysis, vacuum aspiration has no adverse effect on the cellular components except on casts.
Device for inspecting vessel surfaces
Appel, D. Keith
1995-01-01
A portable, remotely-controlled inspection crawler for use along the walls of tanks, vessels, piping and the like. The crawler can be configured to use a vacuum chamber for supporting itself on the inspected surface by suction or a plurality of magnetic wheels for moving the crawler along the inspected surface. The crawler is adapted to be equipped with an ultrasonic probe for mapping the structural integrity or other characteristics of the surface being inspected. Navigation of the crawler is achieved by triangulation techniques between a signal transmitter on the crawler and a pair of microphones attached to a fixed, remote location, such as the crawler's deployment unit. The necessary communications are established between the crawler and computers external to the inspection environment for position control and storage and/or monitoring of data acquisition.
K(3)EDTA Vacuum Tubes Validation for Routine Hematological Testing.
Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Poli, Giovanni; Solero, Giovanni Pietro; Picheth, Geraldo; Guidi, Gian Cesare
2012-01-01
Background and Objective. Some in vitro diagnostic devices (e.g, blood collection vacuum tubes and syringes for blood analyses) are not validated before the quality laboratory managers decide to start using or to change the brand. Frequently, the laboratory or hospital managers select the vacuum tubes for blood collection based on cost considerations or on relevance of a brand. The aim of this study was to validate two dry K(3)EDTA vacuum tubes of different brands for routine hematological testing. Methods. Blood specimens from 100 volunteers in two different K(3)EDTA vacuum tubes were collected by a single, expert phlebotomist. The routine hematological testing was done on Advia 2120i hematology system. The significance of the differences between samples was assessed by paired Student's t-test after checking for normality. The level of statistical significance was set at P < 0.05. Results and Conclusions. Different brand's tubes evaluated can represent a clinically relevant source of variations only on mean platelet volume (MPV) and platelet distribution width (PDW). Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according to him/her technical or economical reasons for routine hematological tests.
Magnesium fluoride reduction-vessel liners. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Latham-Brown, C.E.
1986-03-26
The work described in this report details a program that demonstrated a method by which magnesium fluoride, the by-product of the reduction reaction of uranium tetrafluoride to uranium metal could be used to replace the present graphite used to line the reduction vessel. Utilization of magnesium fluoride (MgF2) as a reduction-vessel liner has the potential to decrease carbon contamination and thereby reduce DU derby rejects due to chemistry. Additionally, there would be the elimination of the cost of the graphite crucible liner and the associated disposal costs by replacement with the by-product of the reduction reaction, which is magnesium fluoride.more » The process would ultimately result in reduced manufacturing costs for derby metal and higher yield of finished penetrators. This was to be accomplished in such a manner as to produce uranium metal derbies which would be accommodated into the present Nuclear Metals-Carolina Metals penetrator production process with minimal changes in equipment and procedures.« less
49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.
Code of Federal Regulations, 2010 CFR
2010-10-01
.... The following requirements apply to vehicles with vacuum brake assist units and vacuum brake systems. (a) Vacuum brake assist unit integrity. The vacuum brake assist unit shall demonstrate integrity as... maintained on the pedal. (1) Inspection procedure. Stop the engine and apply service brake several times to...
Demonstrations with a Vacuum: Old Demonstrations for New Vacuum Pumps.
ERIC Educational Resources Information Center
Greenslade, Thomas B., Jr.
1989-01-01
Explains mechanisms of 19th-century vacuum pumps. Describes demonstrations using the pump including guinea and feather tube, aurora tube, electric egg, Gassiots cascade, air mill, bell in vacuum, density and buoyancy of air, fountain in vacuum, mercury shower, palm and bladder glasses, Bacchus demonstration, pneumatic man-lifter, and Magdeburg…
OceanRoute: Vessel Mobility Data Processing and Analyzing Model Based on MapReduce
NASA Astrophysics Data System (ADS)
Liu, Chao; Liu, Yingjian; Guo, Zhongwen; Jing, Wei
2018-06-01
The network coverage is a big problem in ocean communication, and there is no low-cost solution in the short term. Based on the knowledge of Mobile Delay Tolerant Network (MDTN), the mobility of vessels can create the chances of end-to-end communication. The mobility pattern of vessel is one of the key metrics on ocean MDTN network. Because of the high cost, few experiments have focused on research of vessel mobility pattern for the moment. In this paper, we study the traces of more than 4000 fishing and freight vessels. Firstly, to solve the data noise and sparsity problem, we design two algorithms to filter the noise and complement the missing data based on the vessel's turning feature. Secondly, after studying the traces of vessels, we observe that the vessel's traces are confined by invisible boundary. Thirdly, through defining the distance between traces, we design MR-Similarity algorithm to find the mobility pattern of vessels. Finally, we realize our algorithm on cluster and evaluate the performance and accuracy. Our results can provide the guidelines on design of data routing protocols on ocean MDTN.
Ship Compliance in Emission Control Areas: Technology Costs and Policy Instruments.
Carr, Edward W; Corbett, James J
2015-08-18
This paper explores whether a Panama Canal Authority pollution tax could be an effective economic instrument to achieve Emission Control Area (ECA)-like reductions in emissions from ships transiting the Panama Canal. This tariff-based policy action, whereby vessels in compliance with International Maritime Organisation (IMO) ECA standards pay a lower transit tariff than noncompliant vessels, could be a feasible alternative to petitioning for a Panamanian ECA through the IMO. A $4.06/container fuel tax could incentivize ECA-compliant emissions reductions for nearly two-thirds of Panama Canal container vessels, mainly through fuel switching; if the vessel(s) also operate in IMO-defined ECAs, exhaust-gas treatment technologies may be cost-effective. The RATES model presented here compares current abatement technologies based on hours of operation within an ECA, computing costs for a container vessel to comply with ECA standards in addition to computing the Canal tax that would reduce emissions in Panama. Retrofitted open-loop scrubbers are cost-effective only for vessels operating within an ECA for more than 4500 h annually. Fuel switching is the least-cost option to industry for vessels that operate mostly outside of ECA regions, whereas vessels operating entirely within an ECA region could reduce compliance cost with exhaust-gas treatment technology (scrubbers).
NASA Astrophysics Data System (ADS)
Cockman, John
2003-04-01
This apparatus is a modification to the well-known "vacuum bazooka" (PIRA 2B30.70). My vacuum bazooka is easy to construct and demonstrate, requires no precise fittings, foil, or vacuum grease, and propels ping-pong balls at a tremendous velocity!
Apollo experience report: Manned thermal-vacuum testing of spacecraft
NASA Technical Reports Server (NTRS)
Mclane, J. C., Jr.
1974-01-01
Manned thermal-vacuum tests of the Apollo spacecraft presented many first-time problems in the areas of test philosophy, operational concepts, and program implementation. The rationale used to resolve these problems is explained and examined critically in view of actual experience. The series of 12 tests involving 1517 hours of chamber operating time resulted in the disclosure of numerous equipment and procedural deficiencies of significance to the flight mission. Test experience and results in view of subsequent flight experience confirmed that thermal-vacuum testing of integrated manned spacecraft provides a feasible, cost-effective, and safe technique with which to obtain maximum confidence in spacecraft flight worthiness early in the program.
NASA Astrophysics Data System (ADS)
Rahaman, Sabina; Sunil, M. Anantha; Shaik, Habibuddin; Ghosh, Kaustab
2018-05-01
Deposition of Cu2SnS3 (CTS) thin films is successfully carried out on soda lime glass substrate using low cost ultrasonic spray pyrolysis technique. Vacuum annealing of CTS films is carried out at different temperatures 350°C, 400°C and 450°C. The present work is to study the effect of annealing temperature on the crystal structure, surface morphology and optical properties of CTS thin films. Structural studies confirm the formation of CTS phase. Raman analysis is carried out to study presence of defects with annealing temperature. Optical studies confirm that film prepared at 450°C temperature is suitable as absorber material for photovoltaic applications.
Rotating Vessels for Growing Protein Crystals
NASA Technical Reports Server (NTRS)
Cottingham, Paul
2005-01-01
Rotating vessels have been proposed as means of growing larger, more nearly uniform protein crystals than would otherwise be possible in the presence of normal Earth gravitation. Heretofore, nonrotating vessels have been used. It is difficult to grow high-quality protein crystals in the terrestrial gravitational field because of convection plumes created by the interaction between gravitation and density gradients in protein-solution depletion layers around growing crystals. The density gradients and the associated convection plumes cause the surfaces of growing crystals to be exposed to nonuniform solution densities, thereby causing the crystals to form in irregular shapes. The microgravitational environment of outer space has been utilized to eliminate gravitation-induced convection, but this approach is generally not favorable because of the high cost and limited availability of space flight. The use of a rotating vessel according to the proposal is intended to ameliorate the effects of gravitation and the resultant convection, relative to the corresponding effects in a non-rotating vessel. The rotation would exert an averaging effect over time, distributing the convective force on the depletion layer. Therefore, the depletion layer would be more nearly uniform and, as a result, the growing crystal would be more nearly perfect. The proposal admits of variations (see figure), including the following: The growing crystal could be rotated about its own central axis or an external axis. The crystal-growth vessel could be of any of various shapes, including cylindrical, hemispherical, conical, and combinations thereof. The crystal-growth vessel could be suspended in a viscous fluid in an outer vessel to isolate the growing crystal from both ambient vibrations and vibrations induced by a mechanism that drives the rotation. The rotation could be coupled to the crystal-growth vessel by viscous or magnetic means. The crystal-growth vessel could be supported within the
ERIC Educational Resources Information Center
Boyer, Timothy H.
1985-01-01
The classical vacuum of physics is not empty, but contains a distinctive pattern of electromagnetic fields. Discovery of the vacuum, thermal spectrum, classical electron theory, zero-point spectrum, and effects of acceleration are discussed. Connection between thermal radiation and the classical vacuum reveals unexpected unity in the laws of…
NASA Astrophysics Data System (ADS)
Kohri, Kazunori; Matsui, Hiroki
2017-08-01
In this work, we investigated the electroweak vacuum instability during or after inflation. In the inflationary Universe, i.e., de Sitter space, the vacuum field fluctuations < δ phi 2 > enlarge in proportion to the Hubble scale H2. Therefore, the large inflationary vacuum fluctuations of the Higgs field < δ phi 2 > are potentially catastrophic to trigger the vacuum transition to the negative-energy Planck-scale vacuum state and cause an immediate collapse of the Universe. However, the vacuum field fluctuations < δ phi 2 >, i.e., the vacuum expectation values have an ultraviolet divergence, and therefore a renormalization is necessary to estimate the physical effects of the vacuum transition. Thus, in this paper, we revisit the electroweak vacuum instability from the perspective of quantum field theory (QFT) in curved space-time, and discuss the dynamical behavior of the homogeneous Higgs field phi determined by the effective potential V eff( phi ) in curved space-time and the renormalized vacuum fluctuations < δ phi 2 >ren via adiabatic regularization and point-splitting regularization. We simply suppose that the Higgs field only couples the gravity via the non-minimal Higgs-gravity coupling ξ(μ). In this scenario, the electroweak vacuum stability is inevitably threatened by the dynamical behavior of the homogeneous Higgs field phi, or the formations of AdS domains or bubbles unless the Hubble scale is small enough H< ΛI .
K3EDTA Vacuum Tubes Validation for Routine Hematological Testing
Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Poli, Giovanni; Solero, Giovanni Pietro; Picheth, Geraldo; Guidi, Gian Cesare
2012-01-01
Background and Objective. Some in vitro diagnostic devices (e.g, blood collection vacuum tubes and syringes for blood analyses) are not validated before the quality laboratory managers decide to start using or to change the brand. Frequently, the laboratory or hospital managers select the vacuum tubes for blood collection based on cost considerations or on relevance of a brand. The aim of this study was to validate two dry K3EDTA vacuum tubes of different brands for routine hematological testing. Methods. Blood specimens from 100 volunteers in two different K3EDTA vacuum tubes were collected by a single, expert phlebotomist. The routine hematological testing was done on Advia 2120i hematology system. The significance of the differences between samples was assessed by paired Student's t-test after checking for normality. The level of statistical significance was set at P < 0.05. Results and Conclusions. Different brand's tubes evaluated can represent a clinically relevant source of variations only on mean platelet volume (MPV) and platelet distribution width (PDW). Basically, our validation will permit the laboratory or hospital managers to select the brand's vacuum tubes validated according to him/her technical or economical reasons for routine hematological tests. PMID:22888448
Germanium detector vacuum encapsulation
NASA Technical Reports Server (NTRS)
Madden, N. W.; Malone, D. F.; Pehl, R. H.; Cork, C. P.; Luke, P. N.; Landis, D. A.; Pollard, M. J.
1991-01-01
This paper describes an encapsulation technology that should significantly improve the viability of germanium gamma-ray detectors for a number of important applications. A specialized vacuum chamber has been constructed in which the detector and the encapsulating module are processed in high vacuum. Very high vacuum conductance is achieved within the valveless encapsulating module. The detector module is then sealed without breaking the chamber vacuum. The details of the vacuum chamber, valveless module, processing, and sealing method are presented.
Research of vacuum polymer film on three-dimension surface (Conference Presentation)
NASA Astrophysics Data System (ADS)
Bau, Yung-Han
2016-09-01
This study focused on UV-curable acrylic hybrid of solute in vacuum-deposited on the surface and make it smooth. On the surface coating of the entire process, including the pre-treatment of organic solutes, vacuum, nozzle pressure, airflow, frequency ratio, the surface of the rotation rate, nozzle angle, UV light irradiation time, waste solute recycling.Organic solutes through a flow meter and precise measured,by high pressure or vibration of a piezoelectric material, spray our organic solute in a certain degree of vacuum,leaving nozzle of tiny micro-mist volatiles in a vacuum to form secondary atomization,deposited our surface,Since no UV light irradiation, the surface is a liquid having fluidity, so the non-planar substrates can have good performance, finally it is irradiated by UV light of sufficient energy solidify to form a solid film.The advantage of this approach is that a smooth surface,Strong adhesion, low-cost equipment, low temperature, a wide range of high deposition rate can be combined with other deposition method,Under vacuum have not waste because excess paint can be recycled.Avoid solute direct contact with human, relative to the environment-friendly.
NASA Astrophysics Data System (ADS)
Niwa, Yoshimitsu; Kaneko, Eiji
Vacuum circuit breakers (VCB) have been widely used for power distribution systems. Vacuum Interrupters, which are the current interruption unit, have been increased its interruption capability with the development of vacuum arc control technology by magnetic field. There are three major type electrodes: disk shaped electrodes, radial magnetic field electrodes, axial magnetic field (AMF) electrodes. In the disk shaped electrode, the vacuum arc between the electrodes is not controlled. In the AMF electrode, the vacuum arc is diffused and stabilized by an axial magnetic field, which is parallel to the arc current. In the last type of electrodes, the vacuum arc column is rotated by magnetic force generated by the current flowing in the electrodes. The interruption current and the voltage of one break VCB is increased to 100 kA, 144 kV respectively. This paper describes basic configurations and functions of VCB, vacuum arc control technology in vacuum interrupters, recent researches and applications of VCB.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kohri, Kazunori; Matsui, Hiroki, E-mail: kohri@post.kek.jp, E-mail: matshiro@post.kek.jp
In this work, we investigated the electroweak vacuum instability during or after inflation. In the inflationary Universe, i.e., de Sitter space, the vacuum field fluctuations < δ φ {sup 2} > enlarge in proportion to the Hubble scale H {sup 2}. Therefore, the large inflationary vacuum fluctuations of the Higgs field < δ φ {sup 2} > are potentially catastrophic to trigger the vacuum transition to the negative-energy Planck-scale vacuum state and cause an immediate collapse of the Universe. However, the vacuum field fluctuations < δ φ {sup 2} >, i.e., the vacuum expectation values have an ultraviolet divergence, andmore » therefore a renormalization is necessary to estimate the physical effects of the vacuum transition. Thus, in this paper, we revisit the electroweak vacuum instability from the perspective of quantum field theory (QFT) in curved space-time, and discuss the dynamical behavior of the homogeneous Higgs field φ determined by the effective potential V {sub eff}( φ ) in curved space-time and the renormalized vacuum fluctuations < δ φ {sup 2} >{sub ren} via adiabatic regularization and point-splitting regularization. We simply suppose that the Higgs field only couples the gravity via the non-minimal Higgs-gravity coupling ξ(μ). In this scenario, the electroweak vacuum stability is inevitably threatened by the dynamical behavior of the homogeneous Higgs field φ, or the formations of AdS domains or bubbles unless the Hubble scale is small enough H < Λ {sub I} .« less
Luparia, A; Durando, M; Campanino, P; Regini, E; Lucarelli, D; Talenti, A; Mattone, G; Mariscotti, G; Sapino, A; Gandini, G
2011-04-01
The authors sought to evaluate the diagnostic accuracy and cost-effectiveness of vacuum-assisted core biopsy (VACB) in comparison with diagnostic surgical excision for characterisation of nonpalpable breast lesions classified as Breast Imaging Reporting and Data System (BI-RADS) categories R3 and R4. From January 2004 to December 2008, we conducted 602 stereotactic, 11-gauge, VACB procedures on 243 nonpalpable breast lesions categorised as BI-RADS R3, 346 categorised as BI-RADS R4 and 13 categorised as BI-RADS R5. We calculated the diagnostic accuracy and cost savings of VACB by subtracting the cost of the stereotactic biopsy from that of the diagnostic surgical procedure. A total of 56% of the lesions were benign and required no further assessment. Lesions of uncertain malignant potential (B3) (23.6%) were debated at multidisciplinary meetings, and diagnostic surgical biopsy was recommended for 83.1% of them. All malignant lesions (B4 and B5) underwent surgical excision. VACB had a sensitivity of 94.9%, specificity of 98.3% and diagnostic accuracy of 97.7%. The cost savings per VACB procedure were 464.00 euro; by obviating 335 surgical biopsies, the overall cost savings was 155,440.00 euro over 5 years. VACB proved to have high diagnostic accuracy for characterising abnormalities at low to intermediate risk of malignancy and obviated surgical excision in about half of the cases, allowing for considerable cost savings.
Vacuum-sintered body of a novel apatite for artificial bone
NASA Astrophysics Data System (ADS)
Tamura, Kenichi; Fujita, Tatsushi; Morisaki, Yuriko
2013-12-01
We produced regenerative artificial bone material and bone parts using vacuum-sintered bodies of a novel apatite called "Titanium medical apatite (TMA®)" for biomedical applications. TMA was formed by chemically connecting a Ti oxide molecule with the reactive [Ca10(PO4)6] group of Hydroxyapatite (HAp). The TMA powders were kneaded with distilled water, and solid cylinders of compacted TMA were made by compression molding at 10 MPa using a stainless-steel vessel. The TMA compacts were dried and then sintered in vacuum (about 10-3 Pa) or in air using a resistance heating furnace in the temperature range 1073-1773 K. TMA compacts were sintered at temperatures greater than 1073 K, thus resulting in recrystallization. The TMA compact bodies sintered in the range 1273-1773 K were converted into mixtures composed of three crystalline materials: α-TCP (tricalcium phosphate), β-TCP, and Perovskite-CaTiO3. The Perovskite crystals were stable and hard. In vacuum-sintering, the Perovskite crystals were transformed into fibers (approximately 1 µm in diameter × 8 µm in length), and the fiber distribution was uniform in various directions. We refer to the TMA vacuum-sintered bodies as a "reinforced composite material with Perovskite crystal fibers." However, in atmospheric sintering, the Perovskite crystals were of various sizes and were irregularly distributed as a result of the effect of oxygen. After sintering temperature at 1573 K, the following results were obtained: the obtained TMA vacuum-sintered bodies (1) were white, (2) had a density of approximately 2300 kg/m3 (corresponding to that of a compact bone or a tooth), and had a thermal conductivity of approximately 31.3 W/(m·K) (corresponding to those of metal or ceramic implants). Further, it was possible to cut the TMA bodies into various forms with a cutting machine. An implant made of TMA and inserted into a rabbit jaw bone was covered by new bone tissues after just one month because of the high
Kinetics of scrap tyre pyrolysis under vacuum conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lopez, Gartzen; Aguado, Roberto; Olazar, Martin
2009-10-15
Scrap tyre pyrolysis under vacuum is attractive because it allows easier product condensation and control of composition (gas, liquid and solid). With the aim of determining the effect of vacuum on the pyrolysis kinetics, a study has been carried out in thermobalance. Two data analysis methods have been used in the kinetic study: (i) the treatment of experimental data of weight loss and (ii) the deconvolution of DTG (differential thermogravimetry) curve. The former allows for distinguishing the pyrolysis of the three main components (volatile components, natural rubber and styrene-butadiene rubber) according to three successive steps. The latter method identifies themore » kinetics for the pyrolysis of individual components by means of DTG curve deconvolution. The effect of vacuum in the process is significant. The values of activation energy for the pyrolysis of individual components of easier devolatilization (volatiles and NR) are lower for pyrolysis under vacuum with a reduction of 12 K in the reaction starting temperature. The kinetic constant at 503 K for devolatilization of volatile additives at 0.25 atm is 1.7 times higher than that at 1 atm, and that corresponding to styrene-butadiene rubber at 723 K is 2.8 times higher. Vacuum enhances the volatilization and internal diffusion of products in the pyrolysis process, which contributes to attenuating the secondary reactions of the repolymerization and carbonization of these products on the surface of the char (carbon black). The higher quality of carbon black is interesting for process viability. The large-scale implementation of this process in continuous mode requires a comparison to be made between the economic advantages of using a vacuum and the energy costs, which will be lower when the technologies used for pyrolysis require a lower ratio between reactor volume and scrap tyre flow rate.« less
Kinetics of scrap tyre pyrolysis under vacuum conditions.
Lopez, Gartzen; Aguado, Roberto; Olazar, Martín; Arabiourrutia, Miriam; Bilbao, Javier
2009-10-01
Scrap tyre pyrolysis under vacuum is attractive because it allows easier product condensation and control of composition (gas, liquid and solid). With the aim of determining the effect of vacuum on the pyrolysis kinetics, a study has been carried out in thermobalance. Two data analysis methods have been used in the kinetic study: (i) the treatment of experimental data of weight loss and (ii) the deconvolution of DTG (differential thermogravimetry) curve. The former allows for distinguishing the pyrolysis of the three main components (volatile components, natural rubber and styrene-butadiene rubber) according to three successive steps. The latter method identifies the kinetics for the pyrolysis of individual components by means of DTG curve deconvolution. The effect of vacuum in the process is significant. The values of activation energy for the pyrolysis of individual components of easier devolatilization (volatiles and NR) are lower for pyrolysis under vacuum with a reduction of 12K in the reaction starting temperature. The kinetic constant at 503K for devolatilization of volatile additives at 0.25atm is 1.7 times higher than that at 1atm, and that corresponding to styrene-butadiene rubber at 723K is 2.8 times higher. Vacuum enhances the volatilization and internal diffusion of products in the pyrolysis process, which contributes to attenuating the secondary reactions of the repolymerization and carbonization of these products on the surface of the char (carbon black). The higher quality of carbon black is interesting for process viability. The large-scale implementation of this process in continuous mode requires a comparison to be made between the economic advantages of using a vacuum and the energy costs, which will be lower when the technologies used for pyrolysis require a lower ratio between reactor volume and scrap tyre flow rate.
Preventing Clogging In A Vacuum Plasma Spray Gun
NASA Technical Reports Server (NTRS)
Krotz, Phillip D.; Daniel, Ronald L., Jr.; Davis, William M.
1994-01-01
Modification of powder-injection ports enables lengthy, high-temperature deposition operations. Graphite inserts prevent clogging of ports through which copper powder injected into vacuum plasma spray (VPS) gun. Graphite liners eliminate need to spend production time refurbishing VPS gun, reducing cost of production and increasing productivity. Concept also applied to other material systems used for net-shape fabrication via VPS.
Innovative Vacuum Distillation for Magnesium Recycling
NASA Astrophysics Data System (ADS)
Zhu, Tianbai; Li, Naiyi; Mei, Xiaoming; Yu, Alfred; Shang, Shixiang
Magnesium recycling now becomes a very important subject as magnesium consumption increases fast around the world. All commonly used magnesium die-casting alloys can be recycled and recovered to the primary metal quality. The recycled materials may be comprised of biscuits, sprues, runners, flash, overflows, dross, sludge, scrap parts, and old parts that are returned from service, An innovative magnesium recycle method, vacuum distillation, is developed and proved out to be able to recycle magnesium scraps, especially machining chips, oily magnesium, smelting sludge, dross or the mixture. With this process at a specific temperature and environment condition, magnesium in scraps can be gasified and then solidified to become crystal magnesium crown. This `recycled' magnesium crown is collected and used as the raw material of magnesium alloys. The experimental results show the vacuum distillation is a feasible and plausible method to recycle magnesium. Further, the cost analysis will be addressed in this paper.
Invasive Electrical Impedance Tomography for Blood Vessel Detection
Martinsen, Ørjan G.; Kalvøy, Håvard; Grimnes, Sverre; Nordbotten, Bernt; Hol, Per Kristian; Fosse, Erik; Myklebust, Helge; Becker, Lance B
2010-01-01
We present a novel method for localization of large blood vessels using a bioimpedance based needle positioning system on an array of ten monopolar needle electrodes. The purpose of the study is to develop a portable, low cost tool for rapid vascular access for cooling and controlled reperfusion of cardiac arrest patients. Preliminary results show that localization of blood vessels is feasible with this method, but larger studies are necessary to improve the technology. PMID:21611140
Rai, Ansaar T; Evans, Kim; Riggs, Jack E; Hobbs, Gerald R
2016-04-01
Owing to their severity, large vessel occlusion (LVO) strokes may be associated with higher costs that are not reflected in current coding systems. This study aimed to determine whether intravenous thrombolysis costs are related to the presence or absence of LVO. Patients who had undergone intravenous thrombolysis over a 9-year period were divided into LVO and no LVO (nLVO) groups based on admission CT angiography. The primary outcome was hospital cost per admission. Secondary outcomes included admission duration, 90-day clinical outcome, and discharge destination. 119 patients (53%) had LVO and 104 (47%) had nLVO. Total mean±SD cost per LVO patient was $18,815±14,262 compared with $15,174±11,769 per nLVO patient (p=0.04). Hospital payments per admission were $17,338±13,947 and $15,594±16,437 for LVO and nLVO patients, respectively (p=0.4). A good outcome was seen in 33 LVO patients (27.7%) and in 69 nLVO patients (66.4%) (OR 0.2, 95% CI 0.1 to 0.3, p<0.0001). Hospital mortality occurred in 31 LVO patients (26.1%) and in 7 nLVO patients (6.7%) (OR 0.2, 95% CI 0.08 to 0.5, p<0.0001). 31 LVO patients (32.6%) were discharged to home versus 64 nLVO patients (61.5%) (OR 4.5, 95% CI 2.6 to 8, p<0.0001). Admission duration was 7.5±6.9 days in LVO patients versus 4.9±4.2 days in nLVO patients (p=0.0009). Multivariate regression analysis after controlling for comorbidities showed the presence of LVO to be an independent predictor of higher total hospital costs. The presence or absence of LVO is associated with significant differences in hospital costs, outcomes, admission duration, and home discharge. These differences can be important when developing systems of care models for acute ischemic stroke. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Behaviour of tritium in the vacuum vessel of JT-60U
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kobayashi, K.; Miya, N.; Ikeda, Y.
2015-03-15
The disassembly of the JT-60U torus started in 2010 after 18 years of deuterium plasma operations. The vessel is made of Inconel 625. Therefore, it was very important to study the hydrogen isotope (particularly tritium) behavior in Inconel 625 from the viewpoint of the clearance procedure. Inconel 625 specimen was exposed to the D{sub 2} (92.8 %) - T{sub 2} (7.2 %) gas mixture at 573 K for 5 hours. The tritium release from the specimen at 298 K was controlled for about 1 year. After that a part of tritium remaining in the specimen was released by heating upmore » to 1073 K. Other part of tritium trapped in the specimen was measured by chemical etching method. Most of the chemical form of the released tritium was HTO. The contaminated specimen by tritium was released continuously the diffusible tritium under the ambient condition. In the tritium release experiment, the amount of desorbed tritium was about 99% during 1 year. It was considered that the tritium in Inconel 625 was released easily.« less
Device for inspecting vessel surfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Appel, D.K.
1995-12-12
A portable, remotely-controlled inspection crawler is described for use along the walls of tanks, vessels, piping and the like. The crawler can be configured to use a vacuum chamber for supporting itself on the inspected surface by suction or a plurality of magnetic wheels for moving the crawler along the inspected surface. The crawler is adapted to be equipped with an ultrasonic probe for mapping the structural integrity or other characteristics of the surface being inspected. Navigation of the crawler is achieved by triangulation techniques between a signal transmitter on the crawler and a pair of microphones attached to amore » fixed, remote location, such as the crawler`s deployment unit. The necessary communications are established between the crawler and computers external to the inspection environment for position control and storage and/or monitoring of data acquisition. 5 figs.« less
NASA Astrophysics Data System (ADS)
Dorier, J.-L.; Hilleret, N.
1998-11-01
Dust particle contamination is known to be responsible for reduced quality and yield in microelectronic processing. However it may also limit the operation of particle accelerators as a result of beam lifetime reduction or enhanced field emission in radio-frequency accelerating cavities. Intrinsic dust contamination from sources such as valves or ion pumps has not yet been studied due to the inability of commercial particle counters to be able to detect across large cross sections under ultrahigh vacuum (UHV) conditions. This motivated the development of the dust particle detector described here which is able to quantify, in situ, the level of contamination on a representative part of a vacuum vessel. This system operates under UHV conditions and measures flashes of scattered light from free falling dust particles as they cross a thin laser light sheet across a 100 mm diam vacuum vessel. A calibration using microspheres of known diameter has allowed estimation of the particle size from the scattered signal amplitude. Measurements of particulate contamination generated by shocks onto the vessel walls are presented and determination of the height of origin of dust particles from their transit time across the irradiation sheet is discussed. Measurements of dust particle release right to operation of an all-metal gate valve are also presented in the form of time resolved measurements of dust occurrence during the open/close cycles of the valve, as well as histograms of the particle size distribution. A partial self-cleaning effect is witnessed during the first 10 operation cycles following valve installation. The operation of an ion pump has also been investigated and revealed that, in our conditions, particles were released only at pump startup.
Boettcher, Gordon E.
1990-01-01
A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.
Boettcher, Gordon E.
1990-03-06
A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.
Vacuum MOCVD fabrication of high efficience cells
NASA Technical Reports Server (NTRS)
Partain, L. D.; Fraas, L. M.; Mcleod, P. S.; Cape, J. A.
1985-01-01
Vacuum metal-organic-chemical-vapor-deposition (MOCVD) is a new fabrication process with improved safety and easier scalability due to its metal rather than glass construction and its uniform multiport gas injection system. It uses source materials more efficiently than other methods because the vacuum molecular flow conditions allow the high sticking coefficient reactants to reach the substrates as undeflected molecular beams and the hot chamber walls cause the low sticking coefficient reactants to bounce off the walls and interact with the substrates many times. This high source utilization reduces the materials costs power device and substantially decreases the amounts of toxic materials that must be handled as process effluents. The molecular beams allow precise growth control. With improved source purifications, vacuum MOCVD has provided p GaAs layers with 10-micron minority carrier diffusion lengths and GaAs and GaAsSb solar cells with 20% AMO efficiencies at 59X and 99X sunlight concentration ratios. Mechanical stacking has been identified as the quickest, most direct and logical path to stacked multiple-junction solar cells that perform better than the best single-junction devices. The mechanical stack is configured for immediate use in solar arrays and allows interconnections that improve the system end-of-life performance in space.
Compact ECEI system with in-vessel reflective optics for WEST.
Nam, Y B; Park, H K; Lee, W; Yun, G S; Kim, M; Sabot, R; Elbeze, D; Lotte, P; Shen, J
2016-11-01
An electron cyclotron emission imaging (ECEI) diagnostic system for WEST (W Environment for Steady state Tokamak) is under development to study the MHD instabilities affected by tungsten impurities. The system will provide 2-D T e fluctuation images (width × height = ∼18 cm × ∼ 34 cm at low field side and ∼13 cm × ∼ 39 cm at high field side) from a poloidal cross section with high spatial (≤1.7 cm) and temporal (≤2 μs) resolutions. While the key concept and electronic structure are similar to that of prior ECEI systems on other tokamak devices such as KSTAR, DIII-D, or ASDEX-U, part of the imaging optics have to be placed inside the vacuum vessel in order to resolve issues on limited installation space and longer beam path to the detector position. The in-vessel optics consisting of two large curvature-radius mirrors are expected to withstand the extreme heating on long-pulse operation scenario (∼1000 s). The out-vessel optical housing is constructed as compact as possible to remove easily from the installation site in case of necessity. Commissioning of the system is scheduled on the second experimental WEST campaign end of 2017.
Evaluation of Data-Logging Transducer to Passively Collect Pressure Vessel p/T History
NASA Technical Reports Server (NTRS)
Wnuk, Stephen P.; Le, Son; Loew, Raymond A.
2013-01-01
Pressure vessels owned and operated by NASA are required to be regularly certified per agency policy. Certification requires an assessment of damage mechanisms and an estimation of vessel remaining life. Since detail service histories are not typically available for most pressure vessels, a conservative estimate of vessel pressure/temperature excursions is typically used in assessing fatigue life. This paper details trial use of a data-logging transducer to passively obtain actual pressure and temperature service histories of pressure vessels. The approach was found to have some potential for cost savings and other benefits in certain cases.
Reactor pressure vessel with forged nozzles
Desai, Dilip R.
1993-01-01
Inlet nozzles for a gravity-driven cooling system (GDCS) are forged with a cylindrical reactor pressure vessel (RPV) section to which a support skirt for the RPV is attached. The forging provides enhanced RPV integrity around the nozzle and substantial reduction of in-service inspection costs by eliminating GDCS nozzle-to-RPV welds.
NASA Astrophysics Data System (ADS)
Gholami, Mehrdad; Behkami, Shima; Zain, Sharifuddin Md.; Bakirdere, Sezgin
2016-11-01
The objective of this work is to prepare a cost-effective, low reagent consumption and high performance polytetrafluoroethylene (PTFE) vessel that is capable to work in domestic microwave for digesting food and environmental samples. The designed vessel has a relatively thicker wall compared to that of commercial vessels. In this design, eight vessels are placed in an acrylonitrile butadiene styrene (ABS) holder to keep them safe and stable. This vessel needs only 2.0 mL of HNO3 and 1.0 mL H2O2 to digest 100 mg of biological sample. The performance of this design is then evaluated with an ICP-MS instrument in the analysis of the several NIST standard reference material of milk 1849a, rice flour 1568b, spinach leave 1570a and Peach Leaves 1547 in a domestic microwave oven with inverter technology. Outstanding agreement to (SRM) values are observed by using the suggested power to time microwave program, which simulates the reflux action occurring in this closed vessel. Taking into account the high cost of commercial microwave vessels and the volume of chemicals needed for various experiments (8-10 mL), this simple vessel is cost effective and suitable for digesting food and environmental samples.
Vacuum fluctuations in an ancestor vacuum: A possible dark energy candidate
NASA Astrophysics Data System (ADS)
Aoki, Hajime; Iso, Satoshi; Lee, Da-Shin; Sekino, Yasuhiro; Yeh, Chen-Pin
2018-02-01
We consider an open universe created by bubble nucleation, and study possible effects of our "ancestor vacuum," a de Sitter space in which bubble nucleation occurred, on the present universe. We compute vacuum expectation values of the energy-momentum tensor for a minimally coupled scalar field, carefully taking into account the effect of the ancestor vacuum by the Euclidean prescription. We pay particular attention to the so-called supercurvature mode, a non-normalizable mode on a spatial slice of the open universe, which has been known to exist for sufficiently light fields. This mode decays in time most slowly, and may leave residual effects of the ancestor vacuum, potentially observable in the present universe. We point out that the vacuum energy of the quantum field can be regarded as dark energy if mass of the field is of order the present Hubble parameter or smaller. We obtain preliminary results for the dark energy equation of state w (z ) as a function of the redshift.
Wollina, Uwe; Heinig, Birgit; Schönlebe, Jaqueline; Nowak, Andreas
2014-01-01
Elephantiasis nostras is a rare complication in advanced lipo-lymphedema. While lipedema can be treated by liposuction and lymphedema by decongestive lymphatic therapy, elephantiasis nostras may need debulking surgery. We present 2 cases of advanced lipo-lymphedema complicated by elephantiasis nostras. After tumescent microcannular laser-assisted liposuction both patients underwent a debulking surgery with a modification of Auchincloss-Kim's technique. Histologic examination of the tissue specimen was performed. The surgical treatment was well tolerated and primary healing was uneventful. After primary wound healing and ambulation of the patients, a delayed ulceration with lymphorrhea developed. It was treated by surgical necrectomy and vacuum-assisted closure leading to complete healing. Mobility of the leg was much improved. Histologic examination revealed massive ectatic lymphatic vessels nonreactive for podoplanin. Debulking surgery can be an adjuvant technique for elephantiasis nostras in advanced lipo-lymphedema. Although delayed postoperative wound healing problems were observed, necrectomy and vacuum-assisted closure achieved a complete healing. Histologic data suggest that the ectatic lymphatic vessels in these patients resemble finding in podoplanin knockout mice. The findings would explain the limitations of decongestive lymphatic therapy and tumescent liposuction in such patients and their predisposition to relapsing erysipelas.
2D Fast Vessel Visualization Using a Vessel Wall Mask Guiding Fine Vessel Detection
Raptis, Sotirios; Koutsouris, Dimitris
2010-01-01
The paper addresses the fine retinal-vessel's detection issue that is faced in diagnostic applications and aims at assisting in better recognizing fine vessel anomalies in 2D. Our innovation relies in separating key visual features vessels exhibit in order to make the diagnosis of eventual retinopathologies easier to detect. This allows focusing on vessel segments which present fine changes detectable at different sampling scales. We advocate that these changes can be addressed as subsequent stages of the same vessel detection procedure. We first carry out an initial estimate of the basic vessel-wall's network, define the main wall-body, and then try to approach the ridges and branches of the vasculature's using fine detection. Fine vessel screening looks into local structural inconsistencies in vessels properties, into noise, or into not expected intensity variations observed inside pre-known vessel-body areas. The vessels are first modelled sufficiently but not precisely by their walls with a tubular model-structure that is the result of an initial segmentation. This provides a chart of likely Vessel Wall Pixels (VWPs) yielding a form of a likelihood vessel map mainly based on gradient filter's intensity and spatial arrangement parameters (e.g., linear consistency). Specific vessel parameters (centerline, width, location, fall-away rate, main orientation) are post-computed by convolving the image with a set of pre-tuned spatial filters called Matched Filters (MFs). These are easily computed as Gaussian-like 2D forms that use a limited range sub-optimal parameters adjusted to the dominant vessel characteristics obtained by Spatial Grey Level Difference statistics limiting the range of search into vessel widths of 16, 32, and 64 pixels. Sparse pixels are effectively eliminated by applying a limited range Hough Transform (HT) or region growing. Major benefits are limiting the range of parameters, reducing the search-space for post-convolution to only masked regions
The Costs and Benefits of High Speed Vessels Relative to Traditional C-17 Military Airlift
2003-12-01
37 APPENDIX D SWOT Analysis...Port Action Officers Group IBCT Interim Brigade Combat Team LCS Littoral Combat Ship LST Landing ship tank LSV Logistics Support Vessel... SWOT Strength Weakness Opportunity Threat TACOM Tank and Automotive Command TSV Theater Support Vessel USS United States Ship USTRANSCOM
ERIC Educational Resources Information Center
Rathey, Allen
2007-01-01
Upright vacuums, like cars, vary in quality, features and performance. Like automobiles, some uprights are reliable, others may be problematic, and some become a problem as a result of neglect or improper use. So, how do education institutions make an informed choice and, having done so, ensure that an upright vacuum goes the distance? In this…
Rowan, W L; Houshmandyar, S; Phillips, P E; Austin, M E; Beno, J H; Hubbard, A E; Khodak, A; Ouroua, A; Taylor, G
2016-11-01
Measurement of the electron cyclotron emission (ECE) is one of the primary diagnostics for electron temperature in ITER. In-vessel, in-vacuum, and quasi-optical antennas capture sufficient ECE to achieve large signal to noise with microsecond temporal resolution and high spatial resolution while maintaining polarization fidelity. Two similar systems are required. One views the plasma radially. The other is an oblique view. Both views can be used to measure the electron temperature, while the oblique is also sensitive to non-thermal distortion in the bulk electron distribution. The in-vacuum optics for both systems are subject to degradation as they have a direct view of the ITER plasma and will not be accessible for cleaning or replacement for extended periods. Blackbody radiation sources are provided for in situ calibration.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rowan, W. L., E-mail: w.l.rowan@austin.utexas.edu; Houshmandyar, S.; Phillips, P. E.
2016-11-15
Measurement of the electron cyclotron emission (ECE) is one of the primary diagnostics for electron temperature in ITER. In-vessel, in-vacuum, and quasi-optical antennas capture sufficient ECE to achieve large signal to noise with microsecond temporal resolution and high spatial resolution while maintaining polarization fidelity. Two similar systems are required. One views the plasma radially. The other is an oblique view. Both views can be used to measure the electron temperature, while the oblique is also sensitive to non-thermal distortion in the bulk electron distribution. The in-vacuum optics for both systems are subject to degradation as they have a direct viewmore » of the ITER plasma and will not be accessible for cleaning or replacement for extended periods. Blackbody radiation sources are provided for in situ calibration.« less
Microfabricated triggered vacuum switch
Roesler, Alexander W [Tijeras, NM; Schare, Joshua M [Albuquerque, NM; Bunch, Kyle [Albuquerque, NM
2010-05-11
A microfabricated vacuum switch is disclosed which includes a substrate upon which an anode, cathode and trigger electrode are located. A cover is sealed over the substrate under vacuum to complete the vacuum switch. In some embodiments of the present invention, a metal cover can be used in place of the trigger electrode on the substrate. Materials used for the vacuum switch are compatible with high vacuum, relatively high temperature processing. These materials include molybdenum, niobium, copper, tungsten, aluminum and alloys thereof for the anode and cathode. Carbon in the form of graphitic carbon, a diamond-like material, or carbon nanotubes can be used in the trigger electrode. Channels can be optionally formed in the substrate to mitigate against surface breakdown.
ITER in-vessel system design and performance
NASA Astrophysics Data System (ADS)
Parker, R. R.
2000-03-01
The article reviews the design and performance of the in-vessel components of ITER as developed for the Engineering Design Activities (EDA) Final Design Report. The double walled vacuum vessel is the first confinement boundary and is designed to maintain its integrity under all normal and off-normal conditions, e.g. the most intense vertical displacement events (VDEs) and seismic events. The shielding blanket consists of modules connected to a toroidal backplate by flexible connectors which allow differential displacements due to temperature non-uniformities. Breeding blanket modules replace the shield modules for the Enhanced Performance Phase. The divertor concept is based on a cassette structure which is convenient for remote installation and removal. High heat flux (HHF) components are mechanically attached and can be removed and replaced in the hot cell. Operation of the divertor is based on achieving partially detached plasma conditions along and near the separatrix. Nominal heat loads of 5-10 MW/m2 are expected on the target. These are accommodated by HHF technology developed during the EDA. Disruptions and VDEs can lead to melting of the first wall armour but no damage to the underlying structure. Stresses in the main structural components remain within allowable ranges for all postulated disruption and seismic events.
NASA Astrophysics Data System (ADS)
Cheng, Shaoyong; Xiu, Shixin; Wang, Jimei; Shen, Zhengchao
2006-11-01
The greenhouse effect of SF6 is a great concern today. The development of high voltage vacuum circuit breakers becomes more important. The vacuum circuit breaker has minimum pollution to the environment. The vacuum interrupter is the key part of a vacuum circuit breaker. The interrupting characteristics in vacuum and arc-controlling technique are the main problems to be solved for a longer gap distance in developing high voltage vacuum interrupters. To understand the vacuum arc characteristics and provide effective technique to control vacuum arc in a long gap distance, the arc mode transition of a cup-type axial magnetic field electrode is observed by a high-speed charge coupled device (CCD) video camera under different gap distances while the arc voltage and arc current are recorded. The controlling ability of the axial magnetic field on vacuum arc obviously decreases when the gap distance is longer than 40 mm. The noise components and mean value of the arc voltage significantly increase. The effective method for controlling the vacuum arc characteristics is provided by long gap distances based on the test results. The test results can be used as a reference to develop high voltage and large capacity vacuum interrupters.
Facile generation of cell microarrays using vacuum degassing and coverslip sweeping.
Wang, Min S; Luo, Zhen; Cherukuri, Sundar; Nitin, Nitin
2014-07-15
A simple method to generate cell microarrays with high-percentage well occupancy and well-defined cell confinement is presented. This method uses a synergistic combination of vacuum degassing and coverslip sweeping. The vacuum degassing step dislodges air bubbles from the microwells, which in turn enables the cells to enter the microwells, while the physical sweeping step using a glass coverslip removes the excess cells outside the microwells. This low-cost preparation method provides a simple solution to generating cell microarrays that can be performed in basic research laboratories and point-of-care settings for routine cell-based screening assays. Copyright © 2014 Elsevier Inc. All rights reserved.
Do xylem fibers affect vessel cavitation resistance?
Jacobsen, Anna L; Ewers, Frank W; Pratt, R Brandon; Paddock, William A; Davis, Stephen D
2005-09-01
Possible mechanical and hydraulic costs to increased cavitation resistance were examined among six co-occurring species of chaparral shrubs in southern California. We measured cavitation resistance (xylem pressure at 50% loss of hydraulic conductivity), seasonal low pressure potential (P(min)), xylem conductive efficiency (specific conductivity), mechanical strength of stems (modulus of elasticity and modulus of rupture), and xylem density. At the cellular level, we measured vessel and fiber wall thickness and lumen diameter, transverse fiber wall and total lumen area, and estimated vessel implosion resistance using (t/b)(h)(2), where t is the thickness of adjoining vessel walls and b is the vessel lumen diameter. Increased cavitation resistance was correlated with increased mechanical strength (r(2) = 0.74 and 0.76 for modulus of elasticity and modulus of rupture, respectively), xylem density (r(2) = 0.88), and P(min) (r(2) = 0.96). In contrast, cavitation resistance and P(min) were not correlated with decreased specific conductivity, suggesting no tradeoff between these traits. At the cellular level, increased cavitation resistance was correlated with increased (t/b)(h)(2) (r(2) = 0.95), increased transverse fiber wall area (r(2) = 0.89), and decreased fiber lumen area (r(2) = 0.76). To our knowledge, the correlation between cavitation resistance and fiber wall area has not been shown previously and suggests a mechanical role for fibers in cavitation resistance. Fiber efficacy in prevention of vessel implosion, defined as inward bending or collapse of vessels, is discussed.
NASA Astrophysics Data System (ADS)
Entler, S.; Duran, I.; Kocan, M.; Vayakis, G.
2017-07-01
Three vacuum vessel sectors in ITER will be instrumented by the outer vessel steady-state magnetic field sensors. Each sensor unit features a pair of metallic Hall sensors with a sensing layer made of bismuth to measure tangential and normal components of the local magnetic field. The influence of temperature and magnetic field on the Hall coefficient was tested for the temperature range from 25 to 250 oC and the magnetic field range from 0 to 0.5 T. A fit of the Hall coefficient normalized temperature function independent of magnetic field was found, and a model of the Hall coefficient functional dependence at a wide range of temperature and magnetic field was built with the purpose to simplify the calibration procedure.
NASA Technical Reports Server (NTRS)
Zahlava, B. A. (Inventor)
1973-01-01
A vacuum probe surface sampler is described for rapidly sampling relatively large surface areas which possess relatively light loading densities of micro-organism, drug particles or the like. A vacuum head with a hollow handle connected to a suitable vacuum source is frictionally attached to a cone assembly terminating in a flared tip adapted to be passed over the surface to be sampled. A fine mesh screen carried by the vacuum head provides support for a membrane filter which collects the microorganisms or other particles. The head assembly is easily removed from the cone assembly without contacting the cone assembly with human hands.
Development of a Control System for the Teat-End Vacuum in Individual Quarter Milking Systems
Ströbel, Ulrich; Rose-Meierhöfer, Sandra; Öz, Hülya; Brunsch, Reiner
2013-01-01
Progress in sensor technique and electronics has led to a decrease in the costs of electronic and sensor components. In modern dairy farms, having udders in good condition, a lower frequency of udder disease and an extended service life of dairy cows will help ensure competitiveness. The objective of this study was to develop a teat-end vacuum control system with individual quarter actor reaction. Based on a review of the literature, this system is assumed to protect the teat tissue. It reduces the mean teat-end vacuum in the maximum vacuum phase (b) to a level of 20 kPa at a flow rate of 0.25 L/min per quarter. At flow rates higher than 1.50 L/min per quarter, the teat-end vacuum can be controlled to a level of 30 kPa, because in this case it is desirable to have a higher vacuum for the transportation of the milk to the receiver. With this system it is possible for the first time to supply the teat end with low vacuum at low flow rates and with higher vacuum at increasing flow rates in a continuous process with a three second reaction-rate on individual quarter level. This system is completely automated. PMID:23765272
46 CFR 42.05-63 - Ship(s) and vessel(s).
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 2 2010-10-01 2010-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63... BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s) and vessel(s) are interchangeable or synonymous words, and include every description of watercraft...
A thermal vacuum test optimization procedure
NASA Technical Reports Server (NTRS)
Kruger, R.; Norris, H. P.
1979-01-01
An analytical model was developed that can be used to establish certain parameters of a thermal vacuum environmental test program based on an optimization of program costs. This model is in the form of a computer program that interacts with a user insofar as the input of certain parameters. The program provides the user a list of pertinent information regarding an optimized test program and graphs of some of the parameters. The model is a first attempt in this area and includes numerous simplifications. The model appears useful as a general guide and provides a way for extrapolating past performance to future missions.
46 CFR 381.8 - Subsidized vessel participation.
Code of Federal Regulations, 2010 CFR
2010-10-01
... from MARAD an amount for the operating-differential subsidy (ODS) likely to be paid for the carriage of... subsidized bidders; (2) Deriving “augmented bids” for the subsidized operators by adding the ODS amount to... on MARAD's calculation of anticipated costs (less ODS in the case of a subsidized vessel) for the...
Rowan, W. L.; Houshmandyar, S.; Phillips, P. E.; ...
2016-09-07
Measurement of the electron cyclotron emission (ECE) is one of the primary diagnostics for electron temperature in ITER. In-vessel, in-vacuum, and quasi-optical antennas capture sufficient ECE to achieve large signal to noise with microsecond temporal resolution and high spatial resolution while maintaining polarization fidelity. Two similar systems are required. One views the plasma radially. The other is an oblique view. Both views can be used to measure the electron temperature, while the oblique is also sensitive to non-thermal distortion in the bulk electron distribution. The in-vacuum optics for both systems are subject to degradation as they have a direct viewmore » of the ITER plasma and will not be accessible for cleaning or replacement for extended periods. Here, blackbody radiation sources are provided for in situ calibration.« less
A radiation hard vacuum switch
Boettcher, G.E.
1988-07-19
A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction. 3 figs.
Han, Young Keun; Miller, Kevin M
2009-08-01
To compare vacuum rise time, vacuum limit accuracy, and occlusion break surge of 3 new phacoemulsification machines. Jules Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. The vacuum rise time under normal and enhanced aspiration modes, vacuum limit accuracy, and occlusion break surge of the Infiniti Vision System, Stellaris Vision Enhancement System, and WhiteStar Signature Phacoemulsification System were tested. Vacuum rise time and limit accuracy were measured at limit settings of 400 mm Hg and 600 mm Hg. Surge area was recorded at vacuum limit settings of 200 mm Hg, 300 mm Hg, 400 mm Hg, and 500 mm Hg. The Infiniti had the fastest vacuum rise times under normal and enhanced aspiration modes. At 4 seconds, the vacuum limit accuracy was greatest with the Infiniti at the 400 mm Hg limit and the Signature at the 600 mm Hg limit. The Stellaris did not reach either vacuum target. The Infiniti performed better than the other 2 machines during testing of occlusion break surge at all vacuum limit settings above 200 mm Hg. Under controlled laboratory test conditions, the Infiniti had the fastest vacuum rise time, greatest vacuum limit accuracy at 400 mm Hg, and least occlusion break surge. These results can be explained by the lower compliance of the Infiniti system.
Wollina, Uwe; Heinig, Birgit; Schönlebe, Jaqueline; Nowak, Andreas
2014-01-01
Objective: Elephantiasis nostras is a rare complication in advanced lipo-lymphedema. While lipedema can be treated by liposuction and lymphedema by decongestive lymphatic therapy, elephantiasis nostras may need debulking surgery. Methods: We present 2 cases of advanced lipo-lymphedema complicated by elephantiasis nostras. After tumescent microcannular laser-assisted liposuction both patients underwent a debulking surgery with a modification of Auchincloss-Kim's technique. Histologic examination of the tissue specimen was performed. Results: The surgical treatment was well tolerated and primary healing was uneventful. After primary wound healing and ambulation of the patients, a delayed ulceration with lymphorrhea developed. It was treated by surgical necrectomy and vacuum-assisted closure leading to complete healing. Mobility of the leg was much improved. Histologic examination revealed massive ectatic lymphatic vessels nonreactive for podoplanin. Conclusions: Debulking surgery can be an adjuvant technique for elephantiasis nostras in advanced lipo-lymphedema. Although delayed postoperative wound healing problems were observed, necrectomy and vacuum-assisted closure achieved a complete healing. Histologic data suggest that the ectatic lymphatic vessels in these patients resemble finding in podoplanin knockout mice. The findings would explain the limitations of decongestive lymphatic therapy and tumescent liposuction in such patients and their predisposition to relapsing erysipelas. PMID:24741382
Air bearing vacuum seal assembly
Booth, Rex
1978-01-01
An air bearing vacuum seal assembly capable of rotating at the speed of several thousand revolutions per minute using an air cushion to prevent the rotating and stationary parts from touching, and a two stage differential pumping arrangement to maintain the pressure gradient between the air cushion and the vacuum so that the leak rate into the vacuum is, for example, less than 1 .times. 10.sup.-4 Pa m.sup.3 /s. The air bearing vacuum seal has particular application for mounting rotating targets to an evacuated accelerator beam tube for bombardment of the targets with high-power charged particle beams in vacuum.
Vacuum-Gauge Connection For Shipping Container
NASA Technical Reports Server (NTRS)
Henry, Robert H.
1990-01-01
External connector enables measurement of vacuum in stored part. Remote-readout connector added to shipping container and connected to thermo-couple vacuum gauge in vacuum-insulated cryogenic line packed in container. Enables monitoring of condition of vacuum without opening container.
Rodriguez, Maria Isabel; Mendoza, Willis Simancas; Guerra-Palacio, Camilo; Guzman, Nelson Alvis; Tolosa, Jorge E
2015-02-01
The majority of abortions in Colombia continue to take place outside the formal health system under a range of conditions, with the majority of women obtaining misoprostol from a thriving black market for the drug and self-administering the medication. We conducted a cost analysis to compare the costs to the health system of three approaches to the provision of abortion care in Colombia: post-abortion care for complications of unsafe abortions, and for legal abortions in a health facility, misoprostol-only medical abortion and vacuum aspiration abortion. Hospital billing records from three institutions, two large maternity hospitals and one specialist reproductive health clinic, were analysed for procedure and complication rates, and costs by diagnosis. The majority of visits (94%) were to the two hospitals for post-abortion care; the other 6% were for legal abortions. Only one minor complication was found among the women having legal abortions, a complication rate of less than 1%. Among the women presenting for post-abortion care, 5% had complications during their treatment, mainly from infection or haemorrhage. Legal abortions were associated not only with far fewer complications for women, but also lower costs for the health system than for post-abortion care. We calculated based on our findings that for every 1,000 women receiving post-abortion care instead of a legal abortion within the health system, 16 women experienced avoidable complications, and the health system spent US $48,000 managing them. Increasing women's access to safe abortion care would not only reduce complications for women, but would also be a cost-saving strategy for the health system. Copyright © 2015 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ferreira, M.; Doom, L.; Hseuh, H.
2009-09-13
National Synchrotron Light Source II, being constructed at Brookhaven, is a 3-GeV, 500 mA, 3rd generation synchrotron radiation facility with ultra low emittance electron beams. The storage ring vacuum system has a circumference of 792 m and consists of over 250 vacuum chambers with a simulated average operating pressure of less than 1 x 10{sup -9} mbar. A summary of the update design of the vacuum system including girder supports of the chambers, gauges, vacuum pumps, bellows, beam position monitors and simulation of the average pressure will be shown. A brief description of the techniques and procedures for cleaning andmore » mounting the chambers are given.« less
Norrgard, E B; Sitaraman, N; Barry, J F; McCarron, D J; Steinecker, M H; DeMille, D
2016-05-01
We demonstrate a simple and easy method for producing low-reflectivity surfaces that are ultra-high vacuum compatible, may be baked to high temperatures, and are easily applied even on complex surface geometries. Black cupric oxide (CuO) surfaces are chemically grown in minutes on any copper surface, allowing for low-cost, rapid prototyping, and production. The reflective properties are measured to be comparable to commercially available products for creating optically black surfaces. We describe a vacuum apparatus which uses multiple blackened copper surfaces for sensitive, low-background detection of molecules using laser-induced fluorescence.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-07
... charter vessels in the guided halibut sport fishery in International Pacific Halibut Commission Areas 2C... Pacific halibut is allocated between the guided sport (i.e., the charter sector) and the commercial... Fisheries Science Center proposes to conduct a survey of charter vessel owners to collect annual cost and...
NASA Astrophysics Data System (ADS)
Lee, T. J.; Lee, K. S., , Dr; Lee, S. K.
2017-12-01
One of the most important factors in measuring effective porosity by vacuum saturation method is that the air in the pore space can be fully substituted by water during the vacuum saturation process. International Society of Rock Mechanics (ISRM) suggests vacuuming a rock sample submerged in the water, while American Society of Test and Materials (ASTM) vacuuming the sample and water separately and then pour the water to the sample. In this study, we call the former wet-type vacuum saturation (WVS) method and the latter dry-type vacuum saturation (DVS) method, and compare the effective porosity measured by the two different vacuum saturation processes. For that purpose, a vacuum saturation system has been developed, which can support both WVS and DVS by only changing the process by programming. Comparison of effective porosity has been made for a cement mortar and rock samples. As a result, DVS can substitute more void volume to water than WVS, which in turn insists that DVS can provide more exact value of effective porosity than WVS.
Primo vessel inside a lymph vessel emerging from a cancer tissue.
Lee, Sungwoo; Ryu, Yeonhee; Cha, Jinmyung; Lee, Jin-Kyu; Soh, Kwang-Sup; Kim, Sungchul; Lim, Jaekwan
2012-10-01
Primo vessels were observed inside the lymph vessels near the caudal vena cava of a rabbit and a rat and in the thoracic lymph duct of a mouse. In the current work we found a primo vessel inside the lymph vessel that came out from the tumor tissue of a mouse. A cancer model of a nude mouse was made with human lung cancer cell line NCI-H460. We injected fluorescent nanoparticles into the xenografted tumor tissue and studied their flow in blood, lymph, and primo vessels. Fluorescent nanoparticles flowed through the blood vessels quickly in few minutes, and but slowly in the lymph vessels. The bright fluorescent signals of nanoparticles disappeared within one hour in the blood vessels but remained much longer up to several hours in the case of lymph vessels. We found an exceptional case of lymph vessels that remained bright with fluorescence up to 24 hours. After detailed examination we found that the bright fluorescence was due to a putative primo vessel inside the lymph vessel. This rare observation is consistent with Bong-Han Kim's claim on the presence of a primo vascular system in lymph vessels. It provides a significant suggestion on the cancer metastasis through primo vessels and lymph vessels. Copyright © 2012. Published by Elsevier B.V.
1979-12-01
Subsistence: Includes the cost of all edibles , sales taxes, delivery charges, and loading costs. Stores, Supplies, and Equipment: The cost of all...consumable stores, supplies, and expendable equipment other than edibles , fuel, and water. 89 Insurance: Annual cost for H&M, P&I, and port risk for the...Products (50) 3441 3442 3444 3446 3449 105 Screw Machine Products (51) 3450 106 Metal Stampings (51) 3460 107 Cutlery , Hand Tools, Hardware (52) 3420
David Florida Laboratory Thermal Vacuum Data Processing System
NASA Technical Reports Server (NTRS)
Choueiry, Elie
1994-01-01
During 1991, the Space Simulation Facility conducted a survey to assess the requirements and analyze the merits for purchasing a new thermal vacuum data processing system for its facilities. A new, integrated, cost effective PC-based system was purchased which uses commercial off-the-shelf software for operation and control. This system can be easily reconfigured and allows its users to access a local area network. In addition, it provides superior performance compared to that of the former system which used an outdated mini-computer and peripheral hardware. This paper provides essential background on the old data processing system's features, capabilities, and the performance criteria that drove the genesis of its successor. This paper concludes with a detailed discussion of the thermal vacuum data processing system's components, features, and its important role in supporting our space-simulation environment and our capabilities for spacecraft testing. The new system was tested during the ANIK E spacecraft test, and was fully operational in November 1991.
Microgravity Storage Vessels and Conveying-Line Feeders for Cohesive Regolith
NASA Technical Reports Server (NTRS)
Walton, Otis R.; Vollmer, Hubert J.
2013-01-01
Under microgravity, the usual methods of placing granular solids into, or extracting them from, containers or storage vessels will not function. Alternative methods are required to provide a motive force to move the material. New configurations for microgravity regolith storage vessels that do not resemble terrestrial silos, hoppers, or tanks are proposed. The microgravity-compatible bulk-material storage vessels and exit feed configurations are designed to reliably empty and feed cohesive material to transfer vessels or conveying ducts or lines without gravity. A controllable motive force drives the cohesive material to the exit opening(s), and provides a reliable means to empty storage vessels and/or to feed microgravity conveying lines. The proposed designs will function equally well in vacuum, or inside of pressurized enclosures. Typical terrestrial granular solids handling and storage equipment will not function under microgravity, since almost all such equipment relies on gravity to at least move material to an exit location or to place it in the bottom of a container. Under microgravity, there effectively are no directions of up or down, and in order to effect movement of material, some other motive force must be applied to the material. The proposed storage vessels utilize dynamic centrifugal force to effect movement of regolith whenever material needs to be removed from the storage vessel. During simple storage, no dynamic motion or forces are required. The rotation rate during emptying can be controlled to ensure that material will move to the desired exit opening, even if the material is highly cohesive, or has acquired an electrostatic charge. The general concept of this Swirl Action Utilized for Centrifugal Ejection of Regolith (SAUCER) microgravity storage unit/dynamic feeder is to have an effective slot-hopper (based on the converging angles of the top and bottom conical section of the vessel) with an exit slot around the entire periphery of the
Port Needs Study (Vessel Traffic Services Benefits) Volume III
DOT National Transportation Integrated Search
1991-08-01
This study documents the benefits and costs of potential U.S. Coast Guard Vessel : Traffic Services (VTS) in selected U.S. deep water ports on the Atlantic, Gulf and : Pacific Coasts. The U.S. Department of Transportation's Research and Special Progr...
Effects of ultralow oxygen and vacuum treatments on bed bug (Heteroptera: Cimicidae) survival
USDA-ARS?s Scientific Manuscript database
Control of bed bugs has always been problematic, balancing among efficacy, safety, and cost. In this study, ultralow oxygen (ULO) and vacuum treatments were tested on bed bugs to develop a safer, effective, and environmental friendly solution to bed bug infestations. ULO treatments were establishe...
New Developments in Nickel-Hydrogen Dependent Pressure Vessel (DPV) Cell and Battery Design
NASA Technical Reports Server (NTRS)
Caldwell, Dwight B.; Fox, Chris L.; Miller, Lee E.
1997-01-01
THe Dependent Pressure Vessel (DPV) Nickel-Hydrogen (NiH2) design is being developed as an advanced battery for military and commercial, aerospace and terrestrial applications. The DPV cell design offers high specific energy and energy density as well as reduced cost, while retaining the established Individual Pressure Vessel (IPV) technology flight heritage and database. This advanced DPV design also offers a more efficient mechanical, electrical and thermal cell and battery configuration and a reduced part count. The DPV battery design promotes compact, minimum volume packaging and weight efficiency, and delivers cost and weight savings with minimal design risk.
Sustainable Oceanographic Vessels - Setting an Example
NASA Astrophysics Data System (ADS)
van Leer, J. C.
2009-12-01
In response to climate change, global warming and post “peak oil” fuel scarcity, the oceanographic community should consider reducing its carbon foot print. Why should scientists operate inefficient vessels while lecturing the general public on the need to reduce CO2 emissions? We have already seen curtailment of ship schedules and ship lay-ups, due in part to rising fuel costs, following $140/barrel crude oil. When the global recession ends, upward pressure on oil prices will again commence. Who can forecast how high fuel prices may ultimately rise during the typical 25-30 year lifetime of a research vessel? Are we to curtail future work at sea when oceanic climate research is becoming ever more important? A catamaran research vessel has been designed which can be electrically propelled from by a combination of high efficiency generators, photovoltaic panels and/or sails. Sail produced power is transformed with propellers and motor/generators into electric power which is stored in battery banks. This vessel could operate as the first true hybrid oceanographic research vessel. It could even continue operations without fuel in cases of a severe fuel shortage or fueling denial. Since the power produced by any water turbine increases with the cube of the velocity flowing over its propeller, the low fluid friction and high stability of a catamaran, with reasonably slender hulls, provide an important boost to efficient hybrid operation. The author has chartered a 42’ hybrid catamaran sailboat and found it efficient and extremely easy to operate and control. A 79’ motor sailing catamaran research vessel by Lock Crowther Designs will be presented as one example of a sustainable research vessel with excellent speed and sea-keeping. A center well makes operation as a small drilling/coring ship for coastal climate investigation possible. The center well also supports a host of remote sensing and robotic gear handling capabilities.
Niobium Application, Metallurgy and Global Trends in Pressure Vessel Steels
NASA Astrophysics Data System (ADS)
Jansto, Steven G.
Niobium-containing high strength steel materials have been developed for a variety of pressure vessel applications. Through the application of these Nb-bearing steels in demanding applications, the designer and end user experience improved toughness at low temperature, excellent fatigue resistance and fracture toughness and excellent weldability. These enhancements provide structural engineers the opportunity to further improve the pressure vessel design and performance. The Nb-microalloy alloy designs also result in reduced operational production cost at the steel operation, thereby embracing the value-added attribute Nb provides to both the producer and the end user throughout the supply chain. For example, through the adoption of these Nb-containing structural materials, several design-manufacturing companies are considering improved designs which offer improved manufacturability, lower overall cost and better life cycle performance.
Sperstad, Iver Bakken; Stålhane, Magnus; Dinwoodie, Iain; ...
2017-09-23
Optimising the operation and maintenance (O&M) and logistics strategy of offshore wind farms implies the decision problem of selecting the vessel fleet for O&M. Different strategic decision support tools can be applied to this problem, but much uncertainty remains regarding both input data and modelling assumptions. Our paper aims to investigate and ultimately reduce this uncertainty by comparing four simulation tools, one mathematical optimisation tool and one analytic spreadsheet-based tool applied to select the O&M access vessel fleet that minimizes the total O&M cost of a reference wind farm. The comparison shows that the tools generally agree on the optimalmore » vessel fleet, but only partially agree on the relative ranking of the different vessel fleets in terms of total O&M cost. The robustness of the vessel fleet selection to various input data assumptions was tested, and the ranking was found to be particularly sensitive to the vessels' limiting significant wave height for turbine access. Also the parameter with the greatest discrepancy between the tools, implies that accurate quantification and modelling of this parameter is crucial. The ranking is moderately sensitive to turbine failure rates and vessel day rates but less sensitive to electricity price and vessel transit speed.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sperstad, Iver Bakken; Stålhane, Magnus; Dinwoodie, Iain
Optimising the operation and maintenance (O&M) and logistics strategy of offshore wind farms implies the decision problem of selecting the vessel fleet for O&M. Different strategic decision support tools can be applied to this problem, but much uncertainty remains regarding both input data and modelling assumptions. Our paper aims to investigate and ultimately reduce this uncertainty by comparing four simulation tools, one mathematical optimisation tool and one analytic spreadsheet-based tool applied to select the O&M access vessel fleet that minimizes the total O&M cost of a reference wind farm. The comparison shows that the tools generally agree on the optimalmore » vessel fleet, but only partially agree on the relative ranking of the different vessel fleets in terms of total O&M cost. The robustness of the vessel fleet selection to various input data assumptions was tested, and the ranking was found to be particularly sensitive to the vessels' limiting significant wave height for turbine access. Also the parameter with the greatest discrepancy between the tools, implies that accurate quantification and modelling of this parameter is crucial. The ranking is moderately sensitive to turbine failure rates and vessel day rates but less sensitive to electricity price and vessel transit speed.« less
In-vacuum multi-modal monochromator for synchrotron-based hard x-ray micro-imaging
DOE Office of Scientific and Technical Information (OSTI.GOV)
Renier, M., E-mail: renier@esrf.fr; Rack, A.; Valade, J. P.
2016-07-27
The original monochromator design we present consists in a high-vacuum vessel comprising three monochromators mounted side-by-side: a Lauë/Lauë, a Bragg/Bragg, and a double-multilayer monochromator. The selection of one monochromator type is done remotely by sliding laterally the crystal support in the monochromator vessel. In this way, exotic combinations such as Lauë/Bragg are also possible. Installation and commissioning of the new monochromator at ESRF beamline ID19 was carried out 2013-2014 (the multilayers not being installed yet). Beamline ID19 offers not only superb beam characteristics for phase-contrast imaging with a high level of sensitivity but also compared to other synchrotron X-ray imagingmore » facilities a large beam of currently up to 7 cm × 1.3 cm. A wide energy range can be accessed in a fixed-exit mode (depending on the optics chosen the accessible energy range is between 10 keV and 200 keV). A beryllium exit window (10 cm × 10 cm active opening) completes the monochromator assembly.« less
Effects of Ultralow Oxygen and Vacuum Treatments on Bed Bug (Heteroptera: Cimicidae) Survival.
Liu, Yong-Biao; Haynes, Kenneth F
2016-04-22
Control of bed bugs is problematic, balancing among efficacy, safety, and cost. In this study, ultralow oxygen (ULO) and vacuum treatments were tested on bed bugs to develop a safer, effective, and environmentally friendly solution to kill bed bugs on infested items. ULO treatments were established by flushing sealed enclosures with nitrogen. All life stages of bed bugs were found to be susceptible to ULO and vacuum treatments, and efficacy of the treatments increased with reduced oxygen levels, increased treatment time, and temperature. In the ULO treatments, 100% mortality of bed bug nymphs and adults and >98% mortality of bed bug eggs were achieved in the 8-h treatment under 0.1% O 2 atmosphere at 30°C. Different levels of vacuum that yielded different oxygen levels were tested on all life stages of bed bugs. The susceptibility of different stages to vacuum treatments increased from nymphs to adults to eggs. Complete control of all life stages was achieved in 12 h under -982 mbar (-29.0 inHg) vacuum at 30°C. This study demonstrated that bed bugs were very susceptible to low oxygen stresses and ULO and vacuum treatments have potential to be used as effective and safe treatments to decontaminate bed bug-infested removable objects. Published by Oxford University Press on behalf of Entomological Society of America 2016.This work is written by US Government employees and is in the public domain in the United States.
Mushin, Oren P; Bogue, Jarrod T; Esquenazi, Mica D; Toscano, Nicole; Bell, Derek E
2017-05-01
The vacuum assisted closure device (VAC) improves wound-healing when utilized as a bolster to secure split thickness skin grafts (STSG). Patients typically remain hospitalized for VAC therapy; however, home VACs (hVAC) are now available. Limited studies examine burns treated with hVAC as a STSG bolster. A retrospective study of records from an ABA verified regional burn center was conducted over 23 months. Patients included STSGs for burn. Data points included demographics, burn mechanism and location, graft characteristics, hospital length of stay (LOS), and time to heal. Fifty patients were included, with average age of 39 years (range <1-83years). Average burn TBSA was 1.27±1.42 (range 0.05-8.18). Grafted area average was 102.9±128.1cm 2 . The most commonly treated areas were the leg/foot, thigh, and torso (53%, 16%, and 16%, respectively). Average LOS was 1.1±1.2 days. Mean graft-take was 99.2±2.8% with one patient undergoing repeat STSG. Average post-operative time to heal was 16±6 days. A 5-day inpatient stay with a VAC costs an average of $34,635, compared to $9134 for an hVAC over the same period. The hVAC is a cost-effective STSG bolster in the burn population for appropriate candidates. Excellent graft-take and low morbidity rates imply that this is an efficacious alternative for STSG bolster. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.
Vacuum leak detector and method
Edwards, Jr., David
1983-01-01
Apparatus and method for detecting leakage in a vacuum system involves a moisture trap chamber connected to the vacuum system and to a pressure gauge. Moisture in the trap chamber is captured by freezing or by a moisture adsorbent to reduce the residual water vapor pressure therein to a negligible amount. The pressure gauge is then read to determine whether the vacuum system is leaky. By directing a stream of carbon dioxide or helium at potentially leaky parts of the vacuum system, the apparatus can be used with supplemental means to locate leaks.
Robot design for a vacuum environment
NASA Technical Reports Server (NTRS)
Belinski, S.; Trento, W.; Imani-Shikhabadi, R.; Hackwood, S.
1987-01-01
The cleanliness requirements for many processing and manufacturing tasks are becoming ever stricter, resulting in a greater interest in the vacuum environment. Researchers discuss the importance of this special environment, and the development of robots which are physically and functionally suited to vacuum processing tasks. Work is in progress at the Center for robotic Systems in Microelectronics (CRSM) to provide a robot for the manufacture of a revolutionary new gyroscope in high vacuum. The need for vacuum in this and other processes is discussed as well as the requirements for a vacuum-compatible robot. Finally, researchers present details on work done at the CRSM to modify an existing clean-room compatible robot for use at high vacuum.
Tracking Vessels to Illegal Pollutant Discharges Using Multisource Vessel Information
NASA Astrophysics Data System (ADS)
Busler, J.; Wehn, H.; Woodhouse, L.
2015-04-01
Illegal discharge of bilge waters is a significant source of oil and other environmental pollutants in Canadian and international waters. Imaging satellites are commonly used to monitor large areas to detect oily discharges from vessels, off-shore platforms and other sources. While remotely sensed imagery provides a snap-shot picture useful for detecting a spill or the presence of vessels in the vicinity, it is difficult to directly associate a vessel to an observed spill unless the vessel is observed while the discharge is occurring. The situation then becomes more challenging with increased vessel traffic as multiple vessels may be associated with a spill event. By combining multiple sources of vessel location data, such as Automated Information Systems (AIS), Long Range Identification and Tracking (LRIT) and SAR-based ship detection, with spill detections and drift models we have created a system that associates detected spill events with vessels in the area using a probabilistic model that intersects vessel tracks and spill drift trajectories in both time and space. Working with the Canadian Space Agency and the Canadian Ice Service's Integrated Satellite Tracking of Pollution (ISTOP) program, we use spills observed in Canadian waters to demonstrate the investigative value of augmenting spill detections with temporally sequenced vessel and spill tracking information.
Amplatzer vascular plug for rapid vessel occlusion in interventional neuroradiology
Banfield, Jillian C
2016-01-01
The purpose of this paper is to report different uses of endovascular Amplatzer vascular plug (AVP) treatment for rapid vessel occlusion in the field of interventional neuroradiology. We retrospectively reviewed our interventional neuroradiology database from November 2010 to July 2015 and found nine patients who were treated with endovascular AVP. AVP was used for rapid vessel occlusion of common carotid artery (1 patient), internal carotid artery (5 patients), vertebral artery (2 patients), and internal jugular vein (1 patient). A median of three AVPs were used with almost immediate occlusion and no thromboembolic complications. Use of AVP is feasible, safe, rapid, and potentially cost-effective method for rapid occlusion of larger size vessels in the head and neck region for different indications. PMID:26515699
Technical specification for vacuum systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khaw, J.
The vacuum systems at the Stanford Linear Accelerator Center (SLAC) are primarily of all-metal construction and operate at pressures from 10/sup -5/ to 10/sup -11/ Torr. The primary gas loads during operation result from thermal desorption and beam-induced desorption from the vacuum chamber walls. These desorption rates can be extremely high in the case of hydrocarbons and other contaminants. These specifications place a major emphasis on eliminating contamination sources. The specifications and procedures have been written to insure the cleanliness and vacuum integrity of all SLAC vacuum systems, and to assist personnel involved with SLAC vacuum systems in choosing andmore » designing components that are compatible with existing systems and meet the quality and reliability of SLAC vacuum standards. The specification includes requirements on design, procurement, fabrication, chemical cleaning, clean room practices, welding and brazing, helium leak testing, residual gas analyzer testing, bakeout, venting, and pumpdown. Also appended are specifications regarding acceptable vendors, isopropyl alcohol, bakeable valve cleaning procedure, mechanical engineering safety inspection, notes on synchrotron radiation, and specifications of numerous individual components. (LEW)« less
Modelling of nectarine drying under near infrared - Vacuum conditions.
Alaei, Behnam; Chayjan, Reza Amiri
2015-01-01
Drying of nectarine slices was performed to determine the thermal and physical properties in order to reduce product deterioration due to chemical reactions, facilitate storage and lower transportation costs. Because nectarine slices are sensitive to heat with long drying period, the selection of a suitable drying approach is a challenging task. Infrared-vacuum drying can be used as an appropriate method for susceptible materials with high moisture content such as nectarine slices. Modelling of nectarine slices drying was carried out in a thin layer near infraredvacuum conditions. Drying of the samples was implemented at the absolute pressures of 20, 40 and 60 kPa and drying temperatures of 50, 60 and 70°C. Drying behaviour of nectarine slices, as well as the effect of drying conditions on moisture loss trend, drying rate, effective diffusion coefficient, activation energy, shrinkage, colour and energy consumption of nectarine slices, dried in near infrared-vacuum dryer are discussed in this study. Six mathematical models were used to predict the moisture ratio of the samples in thin layer drying. The Midilli model had supremacy in prediction of nectarine slices drying behaviour. The maximum drying rates of the samples were between 0.014-0.047 gwater/gdry material·min. Effective moisture diffusivity of the samples was estimated in the ranges of 2.46·10-10 to 6.48·10-10 m2/s. Activation energy were computed between 31.28 and 35.23 kJ/mol. Minimum shrinkage (48.4%) and total colour difference (15.1) were achieved at temperature of 50°C and absolute pressure of 20 kPa. Energy consumption of the tests was estimated in the ranges of 0.129 to 0.247 kWh. Effective moisture diffusivity was increased with decrease of vacuum pressure and increase of drying temperature but effect of drying temperature on effective moisture diffusivity of nectarine slices was more than vacuum pressure. Activation energy was decreased with decrease in absolute pressure. Total colour
NASA Technical Reports Server (NTRS)
1997-01-01
Under a Space Act Agreement between the Kirby company and Lewis Research Center, NASA technology was applied to a commercial vacuum cleaner product line. Kirby engineers were interested in advanced operational concepts, such as particle flow behavior and vibration, critical factors to improve vacuum cleaner performance. An evaluation of the company 1994 home care system, the Kirby G4, led to the refinement of the new G5 and future models. Under the cooperative agreement, Kirby had access to Lewis' holography equipment, which added insight into how long a vacuum cleaner fan would perform, as well as advanced computer software that can simulate the flow of air through fans. The collaboration resulted in several successes including fan blade redesign and continuing dialogue on how to improve air-flow traits in various nozzle designs.
Controlling air pollution from passenger ferries: cost-effectiveness of seven technological options.
Farrell, Alexander E; Corbett, James J; Winebrake, James J
2002-12-01
Continued interest in improving air quality in the United States along with renewed interest in the expansion of urban passenger ferry service has created concern about air pollution from ferry vessels. This paper presents a methodology for estimating the air pollution emissions from passenger ferries and the costs of emissions control strategies. The methodology is used to estimate the emissions and costs of retrofitting or re-powering ferries with seven technological options (combinations of propulsion and emission control systems) onto three vessels currently in service in San Francisco Bay. The technologies include improved engine design, cleaner fuels (including natural gas), and exhaust gas cleanup devices. The three vessels span a range of ages and technologies, from a 25-year-old monohull to a modern, high-speed catamaran built only four years ago. By looking at a range of technologies, vessel designs, and service conditions, a sense of the broader implications of controlling emissions from passenger ferries across a range of vessels and service profiles is provided. Tier 2-certified engines are the most cost-effective choice, but all options are cost-effective relative to other emission control strategies already in place in the transportation system.
46 CFR 42.05-63 - Ship(s) and vessel(s).
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 2 2011-10-01 2011-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s...
46 CFR 42.05-63 - Ship(s) and vessel(s).
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 2 2013-10-01 2013-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s...
46 CFR 42.05-63 - Ship(s) and vessel(s).
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 2 2012-10-01 2012-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s...
46 CFR 42.05-63 - Ship(s) and vessel(s).
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 2 2014-10-01 2014-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s...
Kaplan, Mark; Daly, Darron; Stemkowski, Stephen
2009-03-01
The cost of treating complex traumatic wounds is substantial because of trauma severity, potential for infection, and delayed closure. Negative pressure wound therapy using reticulated open cell foam (NPWT/ROCF) as delivered by Vacuum-Assisted Closure* (KCI Licensing, Inc, San Antonio, Texas) is an established, viable option for treating traumatic wounds. The authors used retrospective data to study the clinical and cost-effective benefits of using NPWT/ROCF early on day 1 or day 2 of treatment for traumatic wounds as compared with using it late (on day 3 or later). Hospital data records from trauma wound patients treated with NPWT/ROCF were retrospectively analyzed. Data were subdivided into 2 groups based on start of treatment. The group of patients treated on day 1 or 2 of their hospital stay was referred to as the early group, and that composed of patients treated on day 3 or later as the late group. Clinical and cost-effective metrics were compared between the 2 groups. For the early group, 518 patient records were included; 1000 records were reviewed for the late group. Early-group patients had fewer hospital inpatient days (10.6 vs 20.6 days; P < .0001), fewer treatment days (5.1 vs 6.0 days; P = .0498), shorter intensive care unit (ICU) stays (5.3 vs 12.4 days; P < .0001), and higher ICU admission rates (51.5 vs 44.5%; P = .0091) than the late group. Compared with late-group patients, early-group patients had lower total and variable costs per patient discharge ($43,956 vs $32,175; P < .0001 and $22,891 vs $15,805; P < .0001, respectively). Acute-care trauma wound patients receiving early NPWT/ROCF demonstrated significant reductions in length of stay, treatment days, and ICU stay, which resulted in significant reduced patient treatment costs. These results indicate that early intervention with NPWT/ROCF has potential clinical and cost-effective benefits for the treatment of traumatic wounds.
Lange, P; Greco, K; Partington, L; Carvalho, C; Oliani, S; Birchall, M A; Sibbons, P D; Lowdell, M W; Ansari, T
2017-03-01
Tissue engineered tracheae have been successfully implanted to treat a small number of patients on compassionate grounds. The treatment has not become mainstream due to the time taken to produce the scaffold and the resultant financial costs. We have developed a method for decellularization (DC) based on vacuum technology, which when combined with an enzyme/detergent protocol significantly reduces the time required to create clinically suitable scaffolds. We have applied this technology to prepare porcine tracheal scaffolds and compared the results to scaffolds produced under normal atmospheric pressures. The principal outcome measures were the reduction in time (9 days to prepare the scaffold) followed by a reduction in residual DNA levels (DC no-vac: 137.8±48.82 ng/mg vs. DC vac 36.83±18.45 ng/mg, p<0.05.). Our approach did not impact on the collagen or glycosaminoglycan content or on the biomechanical properties of the scaffolds. We applied the vacuum technology to human tracheae, which, when implanted in vivo showed no significant adverse immunological response. The addition of a vacuum to a conventional decellularization protocol significantly reduces production time, whilst providing a suitable scaffold. This increases clinical utility and lowers production costs. To our knowledge this is the first time that vacuum assisted decellularization has been explored. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
Superconducting magnetic energy storage apparatus structural support system
Withers, Gregory J.; Meier, Stephen W.; Walter, Robert J.; Child, Michael D.; DeGraaf, Douglas W.
1992-01-01
A superconducting magnetic energy storage apparatus comprising a cylindrical superconducting coil; a cylindrical coil containment vessel enclosing the coil and adapted to hold a liquid, such as liquefied helium; and a cylindrical vacuum vessel enclosing the coil containment vessel and located in a restraining structure having inner and outer circumferential walls and a floor; the apparatus being provided with horizontal compression members between (1) the coil and the coil containment vessel and (2) between the coil containment vessel and the vacuum vessel, compression bearing members between the vacuum vessel and the restraining structure inner and outer walls, vertical support members (1) between the coil bottom and the coil containment vessel bottom and (2) between the coil containment vessel bottom and the vacuum vessel bottom, and external supports between the vacuum vessel bottom and the restraining structure floor, whereby the loads developed by thermal and magnetic energy changes in the apparatus can be accommodated and the structural integrity of the apparatus be maintained.
Switching Circuit for Shop Vacuum System
NASA Technical Reports Server (NTRS)
Burley, R. K.
1987-01-01
No internal connections to machine tools required. Switching circuit controls vacuum system draws debris from grinders and sanders in machine shop. Circuit automatically turns on vacuum system whenever at least one sander or grinder operating. Debris safely removed, even when operator neglects to turn on vacuum system manually. Pickup coils sense alternating magnetic fields just outside operating machines. Signal from any coil or combination of coils causes vacuum system to be turned on.
Vacuum Brazing of Accelerator Components
NASA Astrophysics Data System (ADS)
Singh, Rajvir; Pant, K. K.; Lal, Shankar; Yadav, D. P.; Garg, S. R.; Raghuvanshi, V. K.; Mundra, G.
2012-11-01
Commonly used materials for accelerator components are those which are vacuum compatible and thermally conductive. Stainless steel, aluminum and copper are common among them. Stainless steel is a poor heat conductor and not very common in use where good thermal conductivity is required. Aluminum and copper and their alloys meet the above requirements and are frequently used for the above purpose. The accelerator components made of aluminum and its alloys using welding process have become a common practice now a days. It is mandatory to use copper and its other grades in RF devices required for accelerators. Beam line and Front End components of the accelerators are fabricated from stainless steel and OFHC copper. Fabrication of components made of copper using welding process is very difficult and in most of the cases it is impossible. Fabrication and joining in such cases is possible using brazing process especially under vacuum and inert gas atmosphere. Several accelerator components have been vacuum brazed for Indus projects at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore using vacuum brazing facility available at RRCAT, Indore. This paper presents details regarding development of the above mentioned high value and strategic components/assemblies. It will include basics required for vacuum brazing, details of vacuum brazing facility, joint design, fixturing of the jobs, selection of filler alloys, optimization of brazing parameters so as to obtain high quality brazed joints, brief description of vacuum brazed accelerator components etc.
Diffuser/ejector system for a very high vacuum environment
NASA Technical Reports Server (NTRS)
Riggs, K. E.; Wojciechowski, C. J. (Inventor)
1984-01-01
Turbo jet engines are used to furnish the necessary high temperature, high volume, medium pressure gas to provide a high vacuum test environment at comparatively low cost for space engines at sea level. Moreover, the invention provides a unique way by use of the variable area ratio ejectors with a pair of meshing cones are used. The outer cone is arranged to translate fore and aft, and the inner cone is interchangeable with other cones having varying angles of taper.
NASA Astrophysics Data System (ADS)
Shioiri, Tetsu; Asari, Naoki; Sato, Junichi; Sasage, Kosuke; Yokokura, Kunio; Homma, Mitsutaka; Suzuki, Katsumi
To investigate the reliability of equipment of vacuum insulation, a study was carried out to clarify breakdown probability distributions in vacuum gap. Further, a double-break vacuum circuit breaker was investigated for breakdown probability distribution. The test results show that the breakdown probability distribution of the vacuum gap can be represented by a Weibull distribution using a location parameter, which shows the voltage that permits a zero breakdown probability. The location parameter obtained from Weibull plot depends on electrode area. The shape parameter obtained from Weibull plot of vacuum gap was 10∼14, and is constant irrespective non-uniform field factor. The breakdown probability distribution after no-load switching can be represented by Weibull distribution using a location parameter. The shape parameter after no-load switching was 6∼8.5, and is constant, irrespective of gap length. This indicates that the scatter of breakdown voltage was increased by no-load switching. If the vacuum circuit breaker uses a double break, breakdown probability at low voltage becomes lower than single-break probability. Although potential distribution is a concern in the double-break vacuum cuicuit breaker, its insulation reliability is better than that of the single-break vacuum interrupter even if the bias of the vacuum interrupter's sharing voltage is taken into account.
Vacuum-insulated catalytic converter
Benson, David K.
2001-01-01
A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.
Vacuum-Induction, Vacuum-Arc, and Air-Induction Melting of a Complex Heat-Resistant Alloy
NASA Technical Reports Server (NTRS)
Decker, R. F.; Rowe, John P.; Freeman, J. W.
1959-01-01
The relative hot-workability and creep-rupture properties at 1600 F of a complex 55Ni-20Cr-15Co-4Mo-3Ti-3Al alloy were evaluated for vacuum-induction, vacuum-arc, and air-induction melting. A limited study of the role of oxygen and nitrogen and the structural effects in the alloy associated with the melting process was carried out. The results showed that the level of boron and/or zirconium was far more influential on properties than the melting method. Vacuum melting did reduce corner cracking and improve surface during hot-rolling. It also resulted in more uniform properties within heats. The creep-rupture properties were slightly superior in vacuum heats at low boron plus zirconium or in heats with zirconium. There was little advantage at high boron levels and air heats were superior at high levels of boron plus zirconium. Vacuum heats also had fewer oxide and carbonitride inclusions although this was a function of the opportunity for separation of the inclusions from high oxygen plus nitrogen heats. The removal of phosphorous by vacuum melting was not found to be related to properties. Oxygen plus nitrogen appeared to increase ductility in creep-rupture tests suggesting that vacuum melting removes unidentified elements detrimental to ductility. Oxides and carbonitrides in themselves did not initiate microcracks. Carbonitrides in the grain boundaries of air heats did initiate microcracks. The role of microcracking from this source and as a function of oxygen and nitrogen content was not clear. Oxygen and nitrogen did intensify corner cracking during hot-rolling but were not responsible for poor surface which resulted from rolling heats melted in air.
Konerman, Monica A; Price, Jennifer; Torres, Dawn; Li, Zhiping
2014-09-01
Large-volume paracentesis (LVP) can be time and labor intensive depending on the amount of ascites removed and the method of drainage. Wall suction has been adopted as the preferred method of drainage at many centers, though the safety and benefits of this technique have not been formally evaluated. The primary objective of this study was to define the cost and time savings of wall suction over the traditional glass vacuum bottle method for ascites drainage. The secondary objective was to compare the safety profile and patient satisfaction using these two techniques. We conducted a randomized, controlled pilot study of the wall suction versus vacuum bottle methods for LVP in hospitalized patients. All LVPs were performed under ultrasound guidance by a single proceduralist. Patients with at least 4 liters removed received 25% intravenous albumin, 8 g/liter fluid removed. Demographic, clinical characteristics, and procedure details were recorded. Laboratory and hemodynamic data were recorded for 24 h prior to and 24-48 h post LVP. An electronic chart review was conducted to evaluate procedure-related complications. Data were compared using Fisher's exact test, t test, or Mann-Whitney U test. Thirty-four patients were randomized to wall suction at 200 mmHg (n = 17) or glass vacuum bottle drainage (n = 17). Wall suction was significantly faster and less costly than vacuum bottle drainage (7 versus 15 min, p = 0.002; $4.59 versus $12.73, p < 0.001). There were no differences in outcomes at 24 and 48 h post LVP, or at 60-day follow up. Performing LVP using wall suction resulted in significantly shorter procedure time and supply cost savings. There were no differences in outcomes between the groups, suggesting equivalent safety, though larger studies powered to detect small differences are needed. Given its efficiency, convenience, and cost effectiveness, wall suction may be a superior method of ascites drainage for LVP.
Shao, Yuchuan; Wang, Qi; Dong, Qingfeng; ...
2015-06-25
The efficiency of organometal trihalide perovskites (OTP) solar cells have reached that parity of single crystal silicon, and its nature abundant raw material and solution-process capability promise a bright future for commercialization. However, the vacuum based techniques for metal electrode deposition and additional encapsulation layer increase the cost of the perovskite solar cells dramatically and impede their commercialization process. Here, we report a vacuum-free low temperature lamination technique to fabricate the top electrode by commercial conductive tapes (C-tape). The simple fabrication method yields good quality contact and high efficiency device of 12.7%. The C-tapes also encapsulated the devices effectively, resultingmore » in greatly improved device stability. As a result, the combination of lamination of electrodes and encapsulation layers into a single step significantly reduce the cost of device fabrication.« less
Computer assisted thermal-vacuum testing
NASA Technical Reports Server (NTRS)
Petrie, W.; Mikk, G.
1977-01-01
In testing complex systems and components under dynamic thermal-vacuum environments, it is desirable to optimize the environment control sequence in order to reduce test duration and cost. This paper describes an approach where a computer is utilized as part of the test control operation. Real time test data is made available to the computer through time-sharing terminals at appropriate time intervals. A mathematical model of the test article and environmental control equipment is then operated on using the real time data to yield current thermal status, temperature analysis, trend prediction and recommended thermal control setting changes to arrive at the required thermal condition. The data acquisition interface and the time-sharing hook-up to an IBM-370 computer is described along with a typical control program and data demonstrating its use.
Improved Methodology for Developing Cost Uncertainty Models for Naval Vessels
2008-09-01
Growth: Last 700 Years (From: Deegan , 2007b) ................13 Figure 3. Business Rules to Consider: Choosing an acceptable cost risk point...requires an understanding of consequence (From: Deegan , 2007b)...............16 Figure 4. Basic Steps in Estimating Probable Systems Cost (From: Book...her guidance and assistance in the development of this thesis. Additionally, I thank Mr. Chris Deegan , the former Director of Cost Engineering and
The thin-wall tube drift chamber operating in vacuum (prototype)
NASA Astrophysics Data System (ADS)
Alexeev, G. D.; Glonti, L. N.; Kekelidze, V. D.; Malyshev, V. L.; Piskun, A. A.; Potrbenikov, Yu. K.; Rodionov, V. K.; Samsonov, V. A.; Tokmenin, V. V.; Shkarovskiy, S. N.
2013-08-01
The goal of this work was to design drift tubes and a chamber operating in vacuum, and to develop technologies for tubes independent assembly and mounting in the chamber. These design and technology were tested on the prototype. The main features of the chamber are the following: the drift tubes are made of flexible mylar film (wall thickness 36 μm, diameter 9.80 mm, length 2160 mm) using ultrasonic welding along the generatrix; the welding device and methods were developed at JINR. Drift tubes with end plugs, anode wires and spacers were completely assembled outside the chamber. "Self-centering" spacers and bushes were used for precise setting of the anode wires and tubes. The assembled tubes were sealed with O-rings in their seats in the chamber which simplified the chamber assembling. Moreover the tube assembly and the chamber manufacture can be performed independently and in parallel; this sufficiently reduces the total time of chamber manufacture and assembling, its cost and allows tubes to be tested outside the chamber. The technology of independent tube assembling is suitable for a chamber of any shape but a round chamber is preferable for operation in vacuum. Single channel amplifier-discriminator boards which are more stable against cross talks were used for testing the tubes. Independently assembled tubes were mounted into the chamber prototype and its performance characteristic measured under the vacuum conditions. The results showed that both the structure and the tubes themselves normally operate. They are suitable for making a full-scale drift chamber for vacuum.
Running vacuum cosmological models: linear scalar perturbations
NASA Astrophysics Data System (ADS)
Perico, E. L. D.; Tamayo, D. A.
2017-08-01
In cosmology, phenomenologically motivated expressions for running vacuum are commonly parameterized as linear functions typically denoted by Λ(H2) or Λ(R). Such models assume an equation of state for the vacuum given by bar PΛ = - bar rhoΛ, relating its background pressure bar PΛ with its mean energy density bar rhoΛ ≡ Λ/8πG. This equation of state suggests that the vacuum dynamics is due to an interaction with the matter content of the universe. Most of the approaches studying the observational impact of these models only consider the interaction between the vacuum and the transient dominant matter component of the universe. We extend such models by assuming that the running vacuum is the sum of independent contributions, namely bar rhoΛ = Σibar rhoΛi. Each Λ i vacuum component is associated and interacting with one of the i matter components in both the background and perturbation levels. We derive the evolution equations for the linear scalar vacuum and matter perturbations in those two scenarios, and identify the running vacuum imprints on the cosmic microwave background anisotropies as well as on the matter power spectrum. In the Λ(H2) scenario the vacuum is coupled with every matter component, whereas the Λ(R) description only leads to a coupling between vacuum and non-relativistic matter, producing different effects on the matter power spectrum.
Cohen, David J; Osnabrugge, Ruben L; Magnuson, Elizabeth A; Wang, Kaijun; Li, Haiyan; Chinnakondepalli, Khaja; Pinto, Duane; Abdallah, Mouin S; Vilain, Katherine A; Morice, Marie-Claude; Dawkins, Keith D; Kappetein, A Pieter; Mohr, Friedrich W; Serruys, Patrick W
2014-09-30
The Synergy Between Percutaneous Coronary Intervention With TAXUS and Cardiac Surgery (SYNTAX) trial demonstrated that in patients with 3-vessel or left main coronary artery disease, coronary artery bypass graft surgery (CABG) was associated with a lower rate of cardiovascular death, myocardial infarction, stroke, or repeat revascularization compared with percutaneous coronary revascularization with drug-eluting stents (DES-PCI)). The long-term cost-effectiveness of these strategies is unknown. Between 2005 and 2007, 1800 patients with left main or 3-vessel coronary artery disease were randomized to CABG (n=897) or DES-PCI (n=903). Costs were assessed from a US perspective, and health state utilities were evaluated with the EuroQOL questionnaire. A patient-level microsimulation model based on the 5-year in-trial data was used to extrapolate costs, life expectancy, and quality-adjusted life expectancy over a lifetime horizon. Although initial procedural costs were $3415 per patient lower with CABG, total hospitalization costs were $10 036 per patient higher. Over the next 5 years, follow-up costs were higher with DES-PCI as a result of more frequent hospitalizations, revascularization procedures, and higher medication costs. Over a lifetime horizon, CABG remained more costly than DES-PCI, but the incremental cost-effectiveness ratio was favorable ($16 537 per quality-adjusted life-year gained) and remained <$20 000 per quality-adjusted life-year in most bootstrap replicates. Results were consistent across a wide range of assumptions about the long-term effect of CABG versus DES-PCI on events and costs. In patients with left main disease or a SYNTAX score ≤22, however, DES-PCI was economically dominant compared with CABG, although these findings were less certain. For most patients with 3-vessel or left main coronary artery disease, CABG is a clinically and economically attractive revascularization strategy compared with DES-PCI. However, among patients with less
14 CFR 29.1433 - Vacuum systems.
Code of Federal Regulations, 2010 CFR
2010-01-01
... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe. (b) Each vacuum air system line and fitting on the discharge side of the pump that might contain...
Vacuum Technology Considerations For Mass Metrology
Abbott, Patrick J.; Jabour, Zeina J.
2011-01-01
Vacuum weighing of mass artifacts eliminates the necessity of air buoyancy correction and its contribution to the measurement uncertainty. Vacuum weighing is also an important process in the experiments currently underway for the redefinition of the SI mass unit, the kilogram. Creating the optimum vacuum environment for mass metrology requires careful design and selection of construction materials, plumbing components, pumping, and pressure gauging technologies. We review the vacuum technology1 required for mass metrology and suggest procedures and hardware for successful and reproducible operation. PMID:26989593
Gas propagation in a liquid helium cooled vacuum tube following a sudden vacuum loss
NASA Astrophysics Data System (ADS)
Dhuley, Ram C.
This dissertation describes the propagation of near atmospheric nitrogen gas that rushes into a liquid helium cooled vacuum tube after the tube suddenly loses vacuum. The loss-of-vacuum scenario resembles accidental venting of atmospheric air to the beam-line of a superconducting radio frequency particle accelerator and is investigated to understand how in the presence of condensation, the in-flowing air will propagate in such geometry. In a series of controlled experiments, room temperature nitrogen gas (a substitute for air) at a variety of mass flow rates was vented to a high vacuum tube immersed in a bath of liquid helium. Pressure probes and thermometers installed on the tube along its length measured respectively the tube pressure and tube wall temperature rise due to gas flooding and condensation. At high mass in-flow rates a gas front propagated down the vacuum tube but with a continuously decreasing speed. Regression analysis of the measured front arrival times indicates that the speed decreases nearly exponentially with the travel length. At low enough mass in-flow rates, no front propagated in the vacuum tube. Instead, the in-flowing gas steadily condensed over a short section of the tube near its entrance and the front appeared to `freeze-out'. An analytical expression is derived for gas front propagation speed in a vacuum tube in the presence of condensation. The analytical model qualitatively explains the front deceleration and flow freeze-out. The model is then simplified and supplemented with condensation heat/mass transfer data to again find the front to decelerate exponentially while going away from the tube entrance. Within the experimental and procedural uncertainty, the exponential decay length-scales obtained from the front arrival time regression and from the simplified model agree.
Okut, Dilara; Devseren, Esra; Koç, Mehmet; Ocak, Özgül Özdestan; Karataş, Haluk; Kaymak-Ertekin, Figen
2018-01-01
Purpose of this study was to develop prototype cooking equipment that can work at reduced pressure and to evaluate its performance for production of strawberry jam. The effect of vacuum cooking conditions on color soluble solid content, reducing sugars total sugars HMF and sensory properties were investigated. Also, the optimum vacuum cooking conditions for strawberry jam were optimized for Composite Rotatable Design. The optimum cooking temperature and time were determined targeting maximum soluble solid content and sensory attributes (consistency) and minimum Hue value and HMF content. The optimum vacuum cooking conditions determined were 74.4 °C temperature and 19.8 time. The soluble solid content strawberry jam made by vacuum process were similar to those prepared by traditional method. HMF contents of jams produced with vacuum cooking method were well within limit of standards.
Vesselness propagation: a fast interactive vessel segmentation method
NASA Astrophysics Data System (ADS)
Cai, Wenli; Dachille, Frank; Harris, Gordon J.; Yoshida, Hiroyuki
2006-03-01
With the rapid development of multi-detector computed tomography (MDCT), resulting in increasing temporal and spatial resolution of data sets, clinical use of computed tomographic angiography (CTA) is rapidly increasing. Analysis of vascular structures is much needed in CTA images; however, the basis of the analysis, vessel segmentation, can still be a challenging problem. In this paper, we present a fast interactive method for CTA vessel segmentation, called vesselness propagation. This method is a two-step procedure, with a pre-processing step and an interactive step. During the pre-processing step, a vesselness volume is computed by application of a CTA transfer function followed by a multi-scale Hessian filtering. At the interactive stage, the propagation is controlled interactively in terms of the priority of the vesselness. This method was used successfully in many CTA applications such as the carotid artery, coronary artery, and peripheral arteries. It takes less than one minute for a user to segment the entire vascular structure. Thus, the proposed method provides an effective way of obtaining an overview of vascular structures.
14 CFR 29.1433 - Vacuum systems.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a.... (b) Each vacuum air system line and fitting on the discharge side of the pump that might contain...
Vacuum status-display and sector-conditioning programs
NASA Astrophysics Data System (ADS)
Skelly, J.; Yen, S.
1990-08-01
Two programs have been developed for observation and control of the AGS vacuum system, which include the following notable features: (1) they incorporate a graphical user interface and (2) they are driven by a relational database which describes the vacuum system. The vacuum system comprises some 440 devices organized into 28 vacuum sectors. The status-display program invites menu selection of a sector, interrogates the relational database for relevant vacuum devices, acquires live readbacks and posts a graphical display of their status. The sector-conditioning program likewise invites sector selection, produces the same status display and also implements process control logic on the sector devices to pump the sector down from atmospheric pressure to high vacuum over a period extending several hours. As additional devices are installed in the vacuum system, the devices are added to the relational database; these programs then automatically include the new devices.
ERIC Educational Resources Information Center
Rathey, Allen
2005-01-01
In this article, the author discusses several myths about vacuum cleaners and offers tips on evaluating and purchasing this essential maintenance tool. These myths are: (1) Amps mean performance; (2) Everyone needs high-efficiency particulate air (HEPA): (3) Picking up a "bowling ball" shows cleaning power; (4) All vacuum bags are the same; (5)…
Port Needs Study (Vessel Traffic Services Benefits) Volume 1: Study Report
DOT National Transportation Integrated Search
1991-08-01
This study documents the benefits and costs of potential U.S. Coast Guard Vessel Traffic Services (VTS) in selected U.S. deep draft ports on the Atlantic, Gulf and Pacific Coasts. The U.S. Department of Transportation's Research and Special Programs ...
Venting and High Vacuum Performance of Low Density Multilayer Insulation
NASA Astrophysics Data System (ADS)
Riesco, M. E.; McLean, C. H.; Mills, G. L.; Buerger, S.; Meyer, M. L.
2010-04-01
The NASA Exploration Program is currently studying the use liquid oxygen, liquid methane and liquid hydrogen for propulsion in future spacecraft for Exploration of the Moon and Mars. This will require the efficient long term, on-orbit storage of these cryogenic propellants. Multilayer Insulation (MLI) will be critical to achieving the required thermal performance since it has much lower heat transfer than any other insulation when used in a vacuum. MLI with a low density (⩽10 layers/cm) has been shown in previous work to be the most mass efficient. The size and mass constraints of these propulsion systems will not allow a structural shell to be used to provide vacuum for the MLI during ground hold and launch. The baseline approach is to purge the MLI during ground hold with an inert gas which is then vented during launch ascent and on-orbit. This paper presents the results on experimental tests and modeling performed by Ball Aerospace on low density, non-perforated MLI used to insulate a cryogenic tank simulating an Exploration cryogenic propellant storage vessel. These include measurements of the rate of venting and of the heat transfer of gas filled insulation, fully evacuated insulation and during the transition in between. Results of transient computer modeling of the MLI venting and heat transfer process are also presented. Previous work by some of the authors performed vent testing using MLI with perforations and slits and a slow pump down rate.
NASA Astrophysics Data System (ADS)
Davydov, A.; Sveshnikov, K.; Voronina, Yu.
2018-01-01
Based on the original combination of analytical methods, computer algebra tools and numerical calculations, proposed recently in Refs. 1-3, the nonperturbative vacuum polarization effects in the 2+1D supercritical Dirac-Coulomb system with Z > Zcr,1 are explored. Both the vacuum charge density ρV P(r→) and vacuum energy ℰV P are considered. The main result of the work is that in the overcritical region ℰV P turns out to be a rapidly decreasing function ˜-ηeffZ3/R with ηeff > 0 and R being the size of the external Coulomb source. Due to a lot of details of calculation the whole work is divided into two parts I and II. In the present part I, we consider the evaluation and behavior of the vacuum density ρV P, which further is used in part II for evaluation of the vacuum energy, with emphasis on the renormalization, convergence of the partial expansion for ρV P and behavior of the integral induced charge QV P in the overcritical region.
NASA Astrophysics Data System (ADS)
Davydov, A.; Sveshnikov, K.; Voronina, Yu.
2018-01-01
Nonperturbative vacuum polarization effects are explored for a supercritical Dirac-Coulomb system with Z > Zcr,1 in 2+1D, based on the original combination of analytical methods, computer algebra and numerical calculations, proposed recently in Refs. 1-3. Both the vacuum charge density ρV P(r→) and vacuum energy ℰV P are considered. Due to a lot of details of calculation the whole work is divided into two parts I and II. Taking account of results, obtained in the part I4 for ρV P, in the present part II, the evaluation of the vacuum energy ℰV P is investigated with emphasis on the renormalization and convergence of the partial expansion for ℰV P. It is shown that the renormalization via fermionic loop turns out to be the universal tool, which removes the divergence of the theory both in the purely perturbative and essentially nonperturbative regimes of the vacuum polarization. The main result of calculation is that for a wide range of the system parameters in the overcritical region ℰV P turns out to be a rapidly decreasing function ˜-ηeffZ3/R with ηeff > 0 and R being the size of the external Coulomb source. To the end the similarity in calculations of ℰV P in 2+1 and 3+1D is discussed, and qualitative arguments are presented in favor of the possibility for complete screening of the classical electrostatic energy of the Coulomb source by the vacuum polarization effects for Z ≫ Zcr,1 in 3+1D.
Quantum vacuum noise in physics and cosmology.
Davies, P. C. W.
2001-09-01
The concept of the vacuum in quantum field theory is a subtle one. Vacuum states have a rich and complex set of properties that produce distinctive, though usually exceedingly small, physical effects. Quantum vacuum noise is familiar in optical and electronic devices, but in this paper I wish to consider extending the discussion to systems in which gravitation, or large accelerations, are important. This leads to the prediction of vacuum friction: The quantum vacuum can act in a manner reminiscent of a viscous fluid. One result is that rapidly changing gravitational fields can create particles from the vacuum, and in turn the backreaction on the gravitational dynamics operates like a damping force. I consider such effects in early universe cosmology and the theory of quantum black holes, including the possibility that the large-scale structure of the universe might be produced by quantum vacuum noise in an early inflationary phase. I also discuss the curious phenomenon that an observer who accelerates through a quantum vacuum perceives a bath of thermal radiation closely analogous to Hawking radiation from black holes, even though an inertial observer registers no particles. The effects predicted raise very deep and unresolved issues about the nature of quantum particles, the role of the observer, and the relationship between the quantum vacuum and the concepts of information and entropy. (c) 2001 American Institute of Physics.
Running vacuum cosmological models: linear scalar perturbations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perico, E.L.D.; Tamayo, D.A., E-mail: elduartep@usp.br, E-mail: tamayo@if.usp.br
In cosmology, phenomenologically motivated expressions for running vacuum are commonly parameterized as linear functions typically denoted by Λ( H {sup 2}) or Λ( R ). Such models assume an equation of state for the vacuum given by P-bar {sub Λ} = - ρ-bar {sub Λ}, relating its background pressure P-bar {sub Λ} with its mean energy density ρ-bar {sub Λ} ≡ Λ/8π G . This equation of state suggests that the vacuum dynamics is due to an interaction with the matter content of the universe. Most of the approaches studying the observational impact of these models only consider the interactionmore » between the vacuum and the transient dominant matter component of the universe. We extend such models by assuming that the running vacuum is the sum of independent contributions, namely ρ-bar {sub Λ} = Σ {sub i} ρ-bar {sub Λ} {sub i} . Each Λ i vacuum component is associated and interacting with one of the i matter components in both the background and perturbation levels. We derive the evolution equations for the linear scalar vacuum and matter perturbations in those two scenarios, and identify the running vacuum imprints on the cosmic microwave background anisotropies as well as on the matter power spectrum. In the Λ( H {sup 2}) scenario the vacuum is coupled with every matter component, whereas the Λ( R ) description only leads to a coupling between vacuum and non-relativistic matter, producing different effects on the matter power spectrum.« less
33 CFR 83.25 - Sailing vessels underway and vessels under oars (Rule 25).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Sailing vessels underway and... OF HOMELAND SECURITY INLAND NAVIGATION RULES RULES Lights and Shapes § 83.25 Sailing vessels underway and vessels under oars (Rule 25). (a) Sailing vessels underway. A sailing vessel underway shall...
33 CFR 83.25 - Sailing vessels underway and vessels under oars (Rule 25).
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Sailing vessels underway and... OF HOMELAND SECURITY INLAND NAVIGATION RULES RULES Lights and Shapes § 83.25 Sailing vessels underway and vessels under oars (Rule 25). (a) Sailing vessels underway. A sailing vessel underway shall...
Altfeder, Igor; Voevodin, Andrey A; Roy, Ajit K
2010-10-15
Field-induced phonon tunneling, a previously unknown mechanism of interfacial thermal transport, has been revealed by ultrahigh vacuum inelastic scanning tunneling microscopy (STM). Using thermally broadened Fermi-Dirac distribution in the STM tip as in situ atomic-scale thermometer we found that thermal vibrations of the last tip atom are effectively transmitted to sample surface despite few angstroms wide vacuum gap. We show that phonon tunneling is driven by interfacial electric field and thermally vibrating image charges, and its rate is enhanced by surface electron-phonon interaction.
21 CFR 884.4340 - Fetal vacuum extractor.
Code of Federal Regulations, 2011 CFR
2011-04-01
... means of a suction cup attached to the scalp and is powered by an external vacuum source. This generic type of device may include the cup, hosing, vacuum source, and vacuum control. (b) Classification...
21 CFR 884.4340 - Fetal vacuum extractor.
Code of Federal Regulations, 2010 CFR
2010-04-01
... means of a suction cup attached to the scalp and is powered by an external vacuum source. This generic type of device may include the cup, hosing, vacuum source, and vacuum control. (b) Classification...
Measurement of partial pressures in vacuum technology and vacuum physics
NASA Technical Reports Server (NTRS)
Huber, W. K.
1986-01-01
It is pointed out that the measurement of gaseous pressures of less than 0.0001 torr is based on the ionization of gas atoms and molecules due to collisions with electrons. The particle density is determined in place of the pressure. The ionization cross sections for molecules of various gases are discussed. It is found that the true pressure in a vacuum system cannot be determined with certainty if it is unknown which gas is present. Effects of partial pressure determination on the condition of the vacuum system are discussed together with ion sources, systems of separation, and ion detection.
VACUUM TRAP AND VALVE COMBINATION
Milleron, N.; Levenson, L.
1963-02-19
This patent relates to a vacuum trap and valve combination suitable for use in large ultra-high vacuum systems. The vacuum trap is a chamber having an inlet and outlet opening which may be made to communicate with a chamber to be evacuated and a diffusion pump, respectively. A valve is designed to hermeticaliy seal with inlet opening and, when opened, block the line-of- sight'' between the inlet and outlet openings, while allowing a large flow path between the opened vaive and the side walls of the trap. The interior of the trap and the side of the valve facing the inlet opening are covered with an impurity absorbent, such as Zeolite or activated aluminum. Besides the advantage of combining two components of a vacuum system into one, the present invention removes the need for a baffle between the pump and the chamber to be evacuated. In one use of a specific embodiment of this invention, the transmission probability was 45 and the partial pressure of the pump fluid vapor in the vacuum chamber was at least 100 times lower than its vapor pressure. (AEC)
Cryostat including heater to heat a target
Pehl, R.H.; Madden, N.W.; Malone, D.F.
1990-09-11
A cryostat is provided which comprises a vacuum vessel; a target disposed within the vacuum vessel; a heat sink disposed within the vacuum vessel for absorbing heat from the detector; a cooling mechanism for cooling the heat sink; a cryoabsorption mechanism for cryoabsorbing residual gas within the vacuum vessel; and a heater for maintaining the target above a temperature at which the residual gas is cryoabsorbed in the course of cryoabsorption of the residual gas by the cryoabsorption mechanism. 2 figs.
Vacuum enhanced cutaneous biopsy instrument
Collins, Joseph
2000-01-01
A syringe-like disposable cutaneous biopsy instrument equipped with a tubular blade at its lower end, and designed so that a vacuum is created during use, said vacuum serving to retain undeformed a plug of tissue cut from a patient's skin.
Troubleshooting crude vacuum tower overhead ejector systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lines, J.R.; Frens, L.L.
1995-03-01
Routinely surveying tower overhead vacuum systems can improve performance and product quality. These vacuum systems normally provide reliable and consistent operation. However, process conditions, supplied utilities, corrosion, erosion and fouling all have an impact on ejector system performance. Refinery vacuum distillation towers use ejector systems to maintain tower top pressure and remove overhead gases. However, as with virtually all refinery equipment, performance may be affected by a number of variables. These variables may act independently or concurrently. It is important to understand basic operating principles of vacuum systems and how performance is affected by: utilities, corrosion and erosion, fouling, andmore » process conditions. Reputable vacuum-system suppliers have service engineers that will come to a refinery to survey the system and troubleshoot performance or offer suggestions for improvement. A skilled vacuum-system engineer may be needed to diagnose and remedy system problems. The affect of these variables on performance is discussed. A case history is described of a vacuum system on a crude tower in a South American refinery.« less
320 x 240 uncooled IRFPA with pixel wise thin film vacuum packaging
NASA Astrophysics Data System (ADS)
Yon, J.-J.; Dumont, G.; Rabaud, W.; Becker, S.; Carle, L.; Goudon, V.; Vialle, C.; Hamelin, A.; Arnaud, A.
2012-10-01
Silicon based vacuum packaging is a key enabling technology for achieving affordable uncooled Infrared Focal Plane Arrays (IRFPA) as required by the promising mass market for very low cost IR applications, such as automotive driving assistance, energy loss monitoring in buildings, motion sensors… Among the various approaches studied worldwide, the CEA, LETI is developing a unique technology where each bolometer pixel is sealed under vacuum at the wafer level, using an IR transparent thin film deposition. This technology referred to as PLP (Pixel Level Packaging), leads to an array of hermetic micro-caps each containing a single microbolometer. Since the successful demonstration that the PLP technology, when applied on a single microbolometer pixel, can provide the required vacuum < 10-3 mbar, the authors have pushed forward the development of the technology on fully operational QVGA readout circuits CMOS base wafers (320 x 240 pixels). In this outlook, the article reports on the electro optical performance obtained from this preliminary PLP based QVGA demonstrator. Apart from the response, noise and NETD distributions, the paper also puts emphasis on additional key features such as thermal time constant, image quality, and ageing properties.
Stone, Christopher M.; Williams, Derrick C.; Price, Jeremy P.
2016-09-23
The Extended Q-Range Small-Angle Neutron Scattering Diffractometer (EQ-SANS) instrument at the Spallation Neutron Source (SNS), Oak Ridge, Tennessee, incorporates a 69m3 detector vessel with a vacuum system which required an upgrade with respect to performance, ease of operation, and maintenance. The upgrade focused on improving pumping performance as well as optimizing system design to minimize opportunity for operational error. This upgrade provided the following practical contributions: Reduced time required to evacuate from atmospheric pressure to 2mTorr from 500-1,000 minutes to 60-70 minutes Provided turn-key automated control with a multi-faceted interlock for personnel and machine safety.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stone, Christopher M.; Williams, Derrick C.; Price, Jeremy P.
The Extended Q-Range Small-Angle Neutron Scattering Diffractometer (EQ-SANS) instrument at the Spallation Neutron Source (SNS), Oak Ridge, Tennessee, incorporates a 69m3 detector vessel with a vacuum system which required an upgrade with respect to performance, ease of operation, and maintenance. The upgrade focused on improving pumping performance as well as optimizing system design to minimize opportunity for operational error. This upgrade provided the following practical contributions: Reduced time required to evacuate from atmospheric pressure to 2mTorr from 500-1,000 minutes to 60-70 minutes Provided turn-key automated control with a multi-faceted interlock for personnel and machine safety.
Joshi, Vinayak S; Reinhardt, Joseph M; Garvin, Mona K; Abramoff, Michael D
2014-01-01
The separation of the retinal vessel network into distinct arterial and venous vessel trees is of high interest. We propose an automated method for identification and separation of retinal vessel trees in a retinal color image by converting a vessel segmentation image into a vessel segment map and identifying the individual vessel trees by graph search. Orientation, width, and intensity of each vessel segment are utilized to find the optimal graph of vessel segments. The separated vessel trees are labeled as primary vessel or branches. We utilize the separated vessel trees for arterial-venous (AV) classification, based on the color properties of the vessels in each tree graph. We applied our approach to a dataset of 50 fundus images from 50 subjects. The proposed method resulted in an accuracy of 91.44% correctly classified vessel pixels as either artery or vein. The accuracy of correctly classified major vessel segments was 96.42%.
A generator for unique quantum random numbers based on vacuum states
NASA Astrophysics Data System (ADS)
Gabriel, Christian; Wittmann, Christoffer; Sych, Denis; Dong, Ruifang; Mauerer, Wolfgang; Andersen, Ulrik L.; Marquardt, Christoph; Leuchs, Gerd
2010-10-01
Random numbers are a valuable component in diverse applications that range from simulations over gambling to cryptography. The quest for true randomness in these applications has engendered a large variety of different proposals for producing random numbers based on the foundational unpredictability of quantum mechanics. However, most approaches do not consider that a potential adversary could have knowledge about the generated numbers, so the numbers are not verifiably random and unique. Here we present a simple experimental setup based on homodyne measurements that uses the purity of a continuous-variable quantum vacuum state to generate unique random numbers. We use the intrinsic randomness in measuring the quadratures of a mode in the lowest energy vacuum state, which cannot be correlated to any other state. The simplicity of our source, combined with its verifiably unique randomness, are important attributes for achieving high-reliability, high-speed and low-cost quantum random number generators.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Medley, S.S.
The application of charge exchange analyzers for the measurement of ion temperature in fusion plasma experiments requires a direct connection between the diagnostic and plasma-discharge vacuum chambers. Differential pumping of the gas load from the diagnostic stripping cell operated at > or approx. = 10/sup -3/ Torr is required to maintain the analyzer chamber at a pressure of < or approx. = 10/sup -6/ Torr. The migration of gases between the diagnostic and plasma vacuum chambers must be minimized. In particular, introduction of the analyzer stripping cell gas into the plasma chamber having a base pressure of < or approx.more » = 10/sup -8/ Torr must be suppressed. The charge exchange diagnostic for the Tokamak Fusion Test Reactor (TFTR) is comprised of two analyzer systems designed to contain a total of 18 independent mass/energy analyzers and one diagnostic neutral beam rated at 80 keV, 15 A. The associated arrays of multiple, interconnected vacuum systems were analyzed using the Vacuum System Transient Simulator (Vsts) computer program which models the transient transport of multigas species through complex networks of ducts, valves, traps, vacuum pumps, and other related vacuum system components. In addition to providing improved design performance at reduced costs, the analysis yields estimates for the exchange of tritium from the torus to the diagnostic components and of the diagnostic working gases to the torus.« less
Vapor-barrier Vacuum Isolation System
NASA Technical Reports Server (NTRS)
Weinstein, Leonard M. (Inventor); Taminger, Karen M. (Inventor)
2014-01-01
A system includes a collimated beam source within a vacuum chamber, a condensable barrier gas, cooling material, a pump, and isolation chambers cooled by the cooling material to condense the barrier gas. Pressure levels of each isolation chamber are substantially greater than in the vacuum chamber. Coaxially-aligned orifices connect a working chamber, the isolation chambers, and the vacuum chamber. The pump evacuates uncondensed barrier gas. The barrier gas blocks entry of atmospheric vapor from the working chamber into the isolation chambers, and undergoes supersonic flow expansion upon entering each isolation chamber. A method includes connecting the isolation chambers to the vacuum chamber, directing vapor to a boundary with the working chamber, and supersonically expanding the vapor as it enters the isolation chambers via the orifices. The vapor condenses in each isolation chamber using the cooling material, and uncondensed vapor is pumped out of the isolation chambers via the pump.
7 CFR 58.423 - Cheese vacuumizing chamber.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 3 2010-01-01 2010-01-01 false Cheese vacuumizing chamber. 58.423 Section 58.423 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....423 Cheese vacuumizing chamber. The vacuum chamber shall be satisfactorily constructed and maintained...
7 CFR 58.423 - Cheese vacuumizing chamber.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 3 2011-01-01 2011-01-01 false Cheese vacuumizing chamber. 58.423 Section 58.423 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....423 Cheese vacuumizing chamber. The vacuum chamber shall be satisfactorily constructed and maintained...
Engineering Matter Interactions Using Squeezed Vacuum
NASA Astrophysics Data System (ADS)
Zeytinoǧlu, Sina; Imamoǧlu, Ataç; Huber, Sebastian
2017-04-01
Virtually all interactions that are relevant for atomic and condensed matter physics are mediated by quantum fluctuations of the electromagnetic field vacuum. Consequently, controlling the vacuum fluctuations can be used to engineer the strength and the range of interactions. Recent experiments have used this premise to demonstrate novel quantum phases or entangling gates by embedding electric dipoles in photonic cavities or wave guides, which modify the electromagnetic fluctuations. Here, we show theoretically that the enhanced fluctuations in the antisqueezed quadrature of a squeezed vacuum state allow for engineering interactions between electric dipoles without the need for a photonic structure. Thus, the strength and range of the interactions can be engineered in a time-dependent way by changing the spatial profile of the squeezed vacuum in a traveling-wave geometry, which also allows the implementation of chiral dissipative interactions. Using experimentally realized squeezing parameters and including realistic losses, we predict single-atom cooperativities C of up to 10 for the squeezed-vacuum-enhanced interactions.
Lightweight Vacuum Jacket for Cryogenic Insulation. Volume 1
NASA Technical Reports Server (NTRS)
Barclay, D. L.; Bell, J. E.; Brogren, E. W.; Straayer, J. W.
1975-01-01
The feasibility of producing a lightweight vacuum jacket using state-of-the-art technology and materials was examined. Design and analytical studies were made on a full-scale, orbital maneuvering system fuel tank. Preliminary design details were made for the tank assembly, including an optimized vacuum jacket and multilayer insulation system. A half-scale LH2 test model was designed and fabricated, and a force/stiffness proof test was conducted on the vacuum jacket. A vacuum leak rate of .000001 atmosphere ml of helium per second was measured, approximately 1500 hours of vacuum pressure were sustained, and 29 vacuum-pressure cycles were experienced prior to failure.
NASA Astrophysics Data System (ADS)
Forsberg, Fredrik; Roxhed, Niclas; Fischer, Andreas C.; Samel, Björn; Ericsson, Per; Hoivik, Nils; Lapadatu, Adriana; Bring, Martin; Kittilsland, Gjermund; Stemme, Göran; Niklaus, Frank
2013-09-01
Imaging in the long wavelength infrared (LWIR) range from 8 to 14 μm is an extremely useful tool for non-contact measurement and imaging of temperature in many industrial, automotive and security applications. However, the cost of the infrared (IR) imaging components has to be significantly reduced to make IR imaging a viable technology for many cost-sensitive applications. This paper demonstrates new and improved fabrication and packaging technologies for next-generation IR imaging detectors based on uncooled IR bolometer focal plane arrays. The proposed technologies include very large scale heterogeneous integration for combining high-performance, SiGe quantum-well bolometers with electronic integrated read-out circuits and CMOS compatible wafer-level vacuum packing. The fabrication and characterization of bolometers with a pitch of 25 μm × 25 μm that are arranged on read-out-wafers in arrays with 320 × 240 pixels are presented. The bolometers contain a multi-layer quantum well SiGe thermistor with a temperature coefficient of resistance of -3.0%/K. The proposed CMOS compatible wafer-level vacuum packaging technology uses Cu-Sn solid-liquid interdiffusion (SLID) bonding. The presented technologies are suitable for implementation in cost-efficient fabless business models with the potential to bring about the cost reduction needed to enable low-cost IR imaging products for industrial, security and automotive applications.
7 CFR 305.29 - Vacuum heat treatment schedule.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 5 2010-01-01 2010-01-01 false Vacuum heat treatment schedule. 305.29 Section 305.29... SERVICE, DEPARTMENT OF AGRICULTURE PHYTOSANITARY TREATMENTS Heat Treatments § 305.29 Vacuum heat treatment... vacuum at 8 hours. Maintain the vacuum until the end of the treatment. Gradually increase the temperature...
[The evolution of vacuum extraction in obstetrics].
Nikolov, A
2010-01-01
Vacuum extraction is one of the methods for assisted vaginal delivery. In this article the evolution of vacuum extraction in obstetrics is been discussed. Historical facts and data from the invention up to state-of-the-art vacuum systems in modern obstetrics are presented.
Major, Matthew J.; Caldwell, Ryan; Fatone, Stefania
2015-01-01
Vacuum-assisted suspension (VAS) of prosthetic sockets utilizes a pump to evacuate air from between the prosthetic liner and socket, and are available as mechanical or electric systems. This technical note describes a hybrid pump that benefits from the advantages of mechanical and electric systems, and evaluates a prototype as proof-of-concept. Cyclical bench testing of the hybrid pump mechanical system was performed using a materials testing system to assess the relationship between compression cycles and vacuum pressure. Phase 1 in vivo testing of the hybrid pump was performed by an able-bodied individual using prosthesis simulator boots walking on a treadmill, and phase 2 involved an above-knee prosthesis user walking with the hybrid pump and a commercial electric pump for comparison. Bench testing of 300 compression cycles produced a maximum vacuum of 24 in-Hg. In vivo testing demonstrated that the hybrid pump continued to pull vacuum during walking, and as opposed to the commercial electric pump, did not require reactivation of the electric system during phase 2 testing. The novelty of the hybrid pump is that while the electric system provides rapid, initial vacuum suspension, the mechanical system provides continuous air evacuation while walking to maintain suspension without reactivation of the electric system, thereby allowing battery power to be reserved for monitoring vacuum levels. PMID:27462383
Gravitational collapse and the vacuum energy
NASA Astrophysics Data System (ADS)
Campos, M.
2014-03-01
To explain the accelerated expansion of the universe, models with interacting dark components (dark energy and dark matter) have been considered recently in the literature. Generally, the dark energy component is physically interpreted as the vacuum energy of the all fields that fill the universe. As the other side of the same coin, the influence of the vacuum energy on the gravitational collapse is of great interest. We study such collapse adopting different parameterizations for the evolution of the vacuum energy. We discuss the homogeneous collapsing star fluid, that interacts with a vacuum energy component, using the stiff matter case as example. We conclude this work with a discussion of the Cahill-McVittie mass for the collapsed object.
Gravitational baryogenesis in running vacuum models
NASA Astrophysics Data System (ADS)
Oikonomou, V. K.; Pan, Supriya; Nunes, Rafael C.
2017-08-01
We study the gravitational baryogenesis mechanism for generating baryon asymmetry in the context of running vacuum models. Regardless of whether these models can produce a viable cosmological evolution, we demonstrate that they produce a nonzero baryon-to-entropy ratio even if the universe is filled with conformal matter. This is a sound difference between the running vacuum gravitational baryogenesis and the Einstein-Hilbert one, since in the latter case, the predicted baryon-to-entropy ratio is zero. We consider two well known and most used running vacuum models and show that the resulting baryon-to-entropy ratio is compatible with the observational data. Moreover, we also show that the mechanism of gravitational baryogenesis may constrain the running vacuum models.
Probabilistic retinal vessel segmentation
NASA Astrophysics Data System (ADS)
Wu, Chang-Hua; Agam, Gady
2007-03-01
Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.
Zhou, Yihui; Wu, Wenbiao; Qiu, Keqiang
2010-11-01
In this research, a two-step process consisting of vacuum pyrolysis and vacuum centrifugal separation was employed to treat waste printed circuit boards (WPCBs). Firstly, WPCBs were pyrolysed under vacuum condition at 600 °C for 30 min in a lab-scale reactor. Then, the obtained pyrolysis residue was heated under vacuum until the solder was melted, and then the molten solder was separated from the pyrolysis residue by the centrifugal force. The results of vacuum pyrolysis showed that the type-A of WPCBs (the base plates of which was made from cellulose paper reinforced phenolic resin) pyrolysed to form an average of 67.97 wt.% residue, 27.73 wt.% oil, and 4.30 wt.% gas; and pyrolysis of the type-B of WPCBs (the base plates of which was made from glass fiber reinforced epoxy resin) led to an average mass balance of 72.20 wt.% residue, 21.45 wt.% oil, and 6.35 wt.% gas. The results of vacuum centrifugal separation showed that the separation of solder was complete when the pyrolysis residue was heated at 400 °C, and the rotating drum was rotated at 1200 rpm for 10 min. The pyrolysis oil and gas can be used as fuel or chemical feedstock after treatment. The pyrolysis residue after solder separation contained various metals, glass fibers and other inorganic materials, which could be recycled for further processing. The recovered solder can be reused directly and it can also be a good resource of lead and tin for refining. Copyright © 2010 Elsevier Ltd. All rights reserved.
Diffraction-limited storage-ring vacuum technology
Al-Dmour, Eshraq; Ahlback, Jonny; Einfeld, Dieter; Tavares, Pedro Fernandes; Grabski, Marek
2014-01-01
Some of the characteristics of recent ultralow-emittance storage-ring designs and possibly future diffraction-limited storage rings are a compact lattice combined with small magnet apertures. Such requirements present a challenge for the design and performance of the vacuum system. The vacuum system should provide the required vacuum pressure for machine operation and be able to handle the heat load from synchrotron radiation. Small magnet apertures result in the conductance of the chamber being low, and lumped pumps are ineffective. One way to provide the required vacuum level is by distributed pumping, which can be realised by the use of a non-evaporable getter (NEG) coating of the chamber walls. It may not be possible to use crotch absorbers to absorb the heat from the synchrotron radiation because an antechamber is difficult to realise with such a compact lattice. To solve this, the chamber walls can work as distributed absorbers if they are made of a material with good thermal conductivity, and distributed cooling is used at the location where the synchrotron radiation hits the wall. The vacuum system of the 3 GeV storage ring of MAX IV is used as an example of possible solutions for vacuum technologies for diffraction-limited storage rings. PMID:25177979
Electric Propulsion Laboratory Vacuum Chamber
1964-06-21
Engineer Paul Reader and his colleagues take environmental measurements during testing of a 20-inch diameter ion engine in a vacuum tank at the Electric Propulsion Laboratory (EPL). Researchers at the Lewis Research Center were investigating the use of a permanent-magnet circuit to create the magnetic field required power electron bombardment ion engines. Typical ion engines use a solenoid coil to create this magnetic field. It was thought that the substitution of a permanent magnet would create a comparable magnetic field with a lower weight. Testing of the magnet system in the EPL vacuum tanks revealed no significant operational problems. Reader found the weight of the two systems was similar, but that the thruster’s efficiency increased with the magnet. The EPL contained a series of large vacuum tanks that could be used to simulate conditions in space. Large vacuum pumps reduced the internal air pressure, and a refrigeration system created the cryogenic temperatures found in space.
Applying the TOC Project Management to Operation and Maintenance Scheduling of a Research Vessel
NASA Astrophysics Data System (ADS)
Manti, M. Firdausi; Fujimoto, Hideo; Chen, Lian-Yi
Marine research vessels and their systems are major assets in the marine resources development. Since the running costs for the ship are very high, it is necessary to reduce the total cost by an efficient scheduling for operation and maintenance. To reduce project period and make it efficient, we applied TOC project management method that is a project management approach developed by Dr. Eli Goldratt. It challenges traditional approaches to project management. It will become the most important improvement in the project management since the development of PERT and critical path methodologies. As a case study, we presented the marine geology research project for the purpose of operations in addition to repair on the repairing dock projects for maintenance of vessels.
Vacuum Energy and Inflation: 4. An Inflationary Universe
ERIC Educational Resources Information Center
Huggins, Elisha
2013-01-01
This is the fourth paper in a series of four. The first paper in the series, "Vacuum Energy and Inflation: 1. A Liter of Vacuum Energy" [EJ1024183] discusses an example of vacuum energy. Vacuum energy is explained as an energy with a negative pressure whose energy density remains constant in an expanding space. Paper 2, "Vacuum…
Tirelli, G; Del Piero, G C; Valentinuz, G; Monte, A; Gatto, A; Rebelli, A; Quatela, E
2018-04-01
To evaluate the clinical efficacy and cost-effectiveness of ultrasonic shears and the electrothermal bipolar vessel sealing system, in comparison to the traditional cold knife and bipolar forceps, in oral and oropharyngeal cancer surgery. Patients who underwent oral or oropharyngeal cancer resection and neck dissection with either ultrasonic shears (n = 36) or electrothermal bipolar vessel sealing (n = 32) were enrolled. Surgical time, intra-operative bleeding, blood drainage, post-operative pain, neck oedema, complications and hospitalisation duration were compared to those of an historical cohort of 36 patients treated using a cold knife and bipolar forceps. Additionally, a cost-effectiveness evaluation was performed. Ultrasonic shears and, in particular, electrothermal bipolar vessel sealing, were advantageous compared to the traditional techniques. The cost of ultrasonic shears and electrothermal bipolar vessel sealing was completely offset by declining time-driven costs for the surgical team and operating theatre. Ultrasonic shears and, in particular, electrothermal bipolar vessel sealing, are more advantageous compared to the traditional techniques, from both a clinical and economic point of view.
21 CFR 884.5070 - Vacuum abortion system.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...
46 CFR 153.368 - Pressure-vacuum valves.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 46 Shipping 5 2014-10-01 2014-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...
46 CFR 153.368 - Pressure-vacuum valves.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 5 2011-10-01 2011-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...
46 CFR 153.368 - Pressure-vacuum valves.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 46 Shipping 5 2012-10-01 2012-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...
46 CFR 153.368 - Pressure-vacuum valves.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 46 Shipping 5 2013-10-01 2013-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...
46 CFR 153.368 - Pressure-vacuum valves.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 5 2010-10-01 2010-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...
21 CFR 884.5070 - Vacuum abortion system.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...
21 CFR 884.5070 - Vacuum abortion system.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...
21 CFR 884.5070 - Vacuum abortion system.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...
21 CFR 884.5070 - Vacuum abortion system.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...
The localized quantum vacuum field
NASA Astrophysics Data System (ADS)
Dragoman, D.
2008-03-01
A model for the localized quantum vacuum is proposed in which the zero-point energy (ZPE) of the quantum electromagnetic field originates in energy- and momentum-conserving transitions of material systems from their ground state to an unstable state with negative energy. These transitions are accompanied by emissions and re-absorptions of real photons, which generate a localized quantum vacuum in the neighborhood of material systems. The model could help resolve the cosmological paradox associated with the ZPE of electromagnetic fields, while reclaiming quantum effects associated with quantum vacuum such as the Casimir effect and the Lamb shift. It also offers a new insight into the Zitterbewegung of material particles.
NASA Astrophysics Data System (ADS)
Munn, Lance
2009-11-01
``Normalization'' of tumor blood vessels has shown promise to improve the efficacy of chemotherapeutics. In theory, anti-angiogenic drugs targeting endothelial VEGF signaling can improve vessel network structure and function, enhancing the transport of subsequent cytotoxic drugs to cancer cells. In practice, the effects are unpredictable, with varying levels of success. The predominant effects of anti-VEGF therapies are decreased vessel leakiness (hydraulic conductivity), decreased vessel diameters and pruning of the immature vessel network. It is thought that each of these can influence perfusion of the vessel network, inducing flow in regions that were previously sluggish or stagnant. Unfortunately, when anti-VEGF therapies affect vessel structure and function, the changes are dynamic and overlapping in time, and it has been difficult to identify a consistent and predictable normalization ``window'' during which perfusion and subsequent drug delivery is optimal. This is largely due to the non-linearity in the system, and the inability to distinguish the effects of decreased vessel leakiness from those due to network structural changes in clinical trials or animal studies. We have developed a mathematical model to calculate blood flow in complex tumor networks imaged by two-photon microscopy. The model incorporates the necessary and sufficient components for addressing the problem of normalization of tumor vasculature: i) lattice-Boltzmann calculations of the full flow field within the vasculature and within the tissue, ii) diffusion and convection of soluble species such as oxygen or drugs within vessels and the tissue domain, iii) distinct and spatially-resolved vessel hydraulic conductivities and permeabilities for each species, iv) erythrocyte particles advecting in the flow and delivering oxygen with real oxygen release kinetics, v) shear stress-mediated vascular remodeling. This model, guided by multi-parameter intravital imaging of tumor vessel structure
Vacuum casting of thick polymeric films
NASA Technical Reports Server (NTRS)
Cuddihy, E. F.; Moacanin, J.
1979-01-01
Bubble formation and layering, which often plague vacuum-evaporated films, are prevented by properly regulating process parameters. Vacuum casting may be applicable to forming thick films of other polymer/solvent solutions.
14 CFR 25.1433 - Vacuum systems.
Code of Federal Regulations, 2010 CFR
2010-01-01
... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe. [Doc. No...
Ceramic vacuum tubes for geothermal well logging
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kelly, R.D.
1977-01-12
The results of investigations carried out into the availability and suitability of ceramic vacuum tubes for the development of logging tools for geothermal wells are summarized. Design data acquired in the evaluation of ceramic vacuum tubes for the development of a 500/sup 0/C instrumentation amplifier are presented. The general requirements for ceramic vacuum tubes for application to the development of high temperature well logs are discussed. Commercially available tubes are described and future contract activities that specifically relate to ceramic vacuum tubes are detailed. Supplemental data is presented in the appendix. (MHR)
Compressed Air/Vacuum Transportation Techniques
NASA Astrophysics Data System (ADS)
Guha, Shyamal
2011-03-01
General theory of compressed air/vacuum transportation will be presented. In this transportation, a vehicle (such as an automobile or a rail car) is powered either by compressed air or by air at near vacuum pressure. Four version of such transportation is feasible. In all versions, a ``c-shaped'' plastic or ceramic pipe lies buried a few inches under the ground surface. This pipe carries compressed air or air at near vacuum pressure. In type I transportation, a vehicle draws compressed air (or vacuum) from this buried pipe. Using turbine or reciprocating air cylinder, mechanical power is generated from compressed air (or from vacuum). This mechanical power transferred to the wheels of an automobile (or a rail car) drives the vehicle. In type II-IV transportation techniques, a horizontal force is generated inside the plastic (or ceramic) pipe. A set of vertical and horizontal steel bars is used to transmit this force to the automobile on the road (or to a rail car on rail track). The proposed transportation system has following merits: virtually accident free; highly energy efficient; pollution free and it will not contribute to carbon dioxide emission. Some developmental work on this transportation will be needed before it can be used by the traveling public. The entire transportation system could be computer controlled.
Vacuum deposition and curing of liquid monomers
Affinito, J.D.
1993-11-09
The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of standard polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.
Vacuum deposition and curing of liquid monomers
Affinito, J.D.
1995-03-07
The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of ``standard`` polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal or oxide may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.
Vacuum deposition and curing of liquid monomers
Affinito, John D.
1993-01-01
The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of "standard" polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.
Vacuum deposition and curing of liquid monomers
Affinito, John D.
1995-01-01
The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of "standard" polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal or oxide may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.
Spacecraft attitude impacts on COLD-SAT non-vacuum jacketed LH2 supply tank thermal performance
NASA Technical Reports Server (NTRS)
Arif, Hugh
1990-01-01
The Cryogenic On-Orbit Liquid Depot - Storage, Acquisition and Transfer (COLD-SAT) spacecraft will be launched into low earth orbit to perform fluid management experiments on the behavior of subcritical liquid hydrogen (LH2). For determining the optimum on-orbit attitude for the COLD-SAT satellite, a comparative analytical study was performed to determine the thermal impacts of spacecraft attitude on the performance of the COLD-SAT non-vacuum jacketed LH2 supply tank. Tank thermal performance was quantitied by total conductive and radiative heat leakage into the pressure vessel due to the absorbed solar, earth albedo and infra-red on-orbit fluxes, and also by the uniformity of the variation of this leakage on the vessel surface area. Geometric and thermal analysis math models were developed for the spacecraft and the tank as part of this analysis, based on their individual thermal/structural designs. Two quasi-inertial spacecraft attitudes were investigated and their effects on the tank performance compared. The results are one of the criteria by which the spacecraft orientation in orbit was selected for the in-house NASA Lewis Research Center design.
Spacecraft attitude impacts on COLD-SAT non-vacuum jacketed LH2 supply tank thermal performance
NASA Technical Reports Server (NTRS)
Arif, Hugh
1990-01-01
The Cryogenic On-Orbit Liquid Depot - Storage, Acquisition and Transfer (COLD-SAT) spacecraft will be launched into low earth orbit to perform fluid management experiments on the behavior of subcritical liquid hydrogen (LH2). For determining the optimum on-orbit attitude for the COLD-SAT satellite, a comparative analytical study was performed to determine the thermal impacts of spacecraft attitude on the performance of the COLD-SAT non-vacuum jacketed LH2 supply tank. Tank thermal performance was quantified by total conductive and radiative heat leakage into the pressure vessel due to the absorbed solar, earth albedo and infra-red on-orbit fluxes, and also by the uniformity of the variation of this leakage on the vessel surface area. Geometric and thermal analysis math models were developed for the spacecraft and the tank as part of this analysis, based on their individual thermal/structural designs. Two quasi-inertial spacecraft attitudes were investigated and their effects on the tank performance compared. The results are one of the criteria by which the spacecraft orientation in orbit was selected for the in-house NASA Lewis Research Center design.
Vacuum-assisted venous return reduces blood usage.
Banbury, Michael K; White, Jennifer A; Blackstone, Eugene H; Cosgrove, Delos M
2003-09-01
To determine whether vacuum-assisted venous return has clinical advantages over conventional gravity drainage apart from allowing the use of smaller cannulas and shorter tubing. A total of 150 valve operations were performed at our institution between February and July 1999 using vacuum-assisted venous return with small venous cannulas connected to short tubing. These were compared with (1) 83 valve operations performed between April 1997 and January 1998 using the initial version of vacuum-assisted venous return, and (2) 124 valve operations performed between January and April of 1997 using conventional gravity drainage. Priming volume, hematocrit value, red blood cell usage, and total blood product usage were compared multivariably. These comparisons were covariate and propensity adjusted for dissimilarities between the groups and confirmed by propensity-matched pairs analysis. Priming volume was 1.4 +/- 0.4 L for small-cannula vacuum-assisted venous return, 1.7 +/- 0.4 L for initial vacuum-assisted venous return, and 2.0 +/- 0.4 L for gravity drainage (P <.0001). Smaller priming resulted in higher hematocrit values both at the beginning of cardiopulmonary bypass (27% +/- 5% compared with 26% +/- 4% and 25% +/- 4%, respectively, P <.0001) and at the end (30% +/- 4% compared with 28% +/- 4% and 27% +/- 4%, respectively, P <.0001). Red cell transfusions were used in 17% of the patients having small-cannula vacuum-assisted venous return, 27% of the initial patients having vacuum-assisted venous return, and 37% of the patients having gravity drainage (P =.001); total blood product usage was 19%, 27%, and 39%, respectively (P =.002). Although ministernotomy also was associated with reduced blood product usage (P <.004), propensity matching on type of sternotomy confirmed the association of vacuum-assisted venous return with lowered blood product usage. Vacuum-assisted venous return results in (1) higher hematocrit values during cardiopulmonary bypass and (2) decreased
Haynie, Alan C.
2016-01-01
Time spent fishing is the effort metric often studied in fisheries but it may under-represent the effort actually expended by fishers. Entire fishing trips, from the time vessels leave port until they return, may prove more useful for examining trends in fleet dynamics, fisher behavior, and fishing costs. However, such trip information is often difficult to resolve. We identified ~30,000 trips made by vessels that targeted walleye pollock (Gadus chalcogrammus) in the Eastern Bering Sea from 2008–2014 by using vessel monitoring system (VMS) and landings data. We compared estimated trip durations to observer data, which were available for approximately half of trips. Total days at sea were estimated with < 1.5% error and 96.4% of trip durations were either estimated with < 5% error or they were within expected measurement error. With 99% accuracy, we classified trips as fishing for pollock, for another target species, or not fishing. This accuracy lends strong support to the use of our method with unobserved trips across North Pacific fisheries. With individual trips resolved, we examined potential errors in datasets which are often viewed as “the truth.” Despite having > 5 million VMS records (timestamps and vessel locations), this study was as much about understanding and managing data errors as it was about characterizing trips. Missing VMS records were pervasive and they strongly influenced our approach. To understand implications of missing data on inference, we simulated removal of VMS records from trips. Removal of records straightened (i.e., shortened) vessel trajectories, and travel distances were underestimated, on average, by 1.5–13.4% per trip. Despite this bias, VMS proved robust for trip characterization and for improved quality control of human-recorded data. Our scrutiny of human-reported and VMS data advanced our understanding of the potential utility and challenges facing VMS users globally. PMID:27788174
Watson, Jordan T; Haynie, Alan C
2016-01-01
Time spent fishing is the effort metric often studied in fisheries but it may under-represent the effort actually expended by fishers. Entire fishing trips, from the time vessels leave port until they return, may prove more useful for examining trends in fleet dynamics, fisher behavior, and fishing costs. However, such trip information is often difficult to resolve. We identified ~30,000 trips made by vessels that targeted walleye pollock (Gadus chalcogrammus) in the Eastern Bering Sea from 2008-2014 by using vessel monitoring system (VMS) and landings data. We compared estimated trip durations to observer data, which were available for approximately half of trips. Total days at sea were estimated with < 1.5% error and 96.4% of trip durations were either estimated with < 5% error or they were within expected measurement error. With 99% accuracy, we classified trips as fishing for pollock, for another target species, or not fishing. This accuracy lends strong support to the use of our method with unobserved trips across North Pacific fisheries. With individual trips resolved, we examined potential errors in datasets which are often viewed as "the truth." Despite having > 5 million VMS records (timestamps and vessel locations), this study was as much about understanding and managing data errors as it was about characterizing trips. Missing VMS records were pervasive and they strongly influenced our approach. To understand implications of missing data on inference, we simulated removal of VMS records from trips. Removal of records straightened (i.e., shortened) vessel trajectories, and travel distances were underestimated, on average, by 1.5-13.4% per trip. Despite this bias, VMS proved robust for trip characterization and for improved quality control of human-recorded data. Our scrutiny of human-reported and VMS data advanced our understanding of the potential utility and challenges facing VMS users globally.
Preventing Pirates from Boarding Commercial Vessels - A Systems Approach
2014-09-01
was developed in MATLAB to run simulations designed to estimate the relative effectiveness of each assessed countermeasure. A cost analysis was...project indicated that the P-Trap countermeasure, designed to entangle the pirate’s propellers with thin lines, is both effective and economically viable...vessels. A model of the operational environment was developed in MATLAB to run simulations designed to estimate the relative effectiveness of each
Purifying Aluminum by Vacuum Distillation
NASA Technical Reports Server (NTRS)
Du Fresne, E. R.
1985-01-01
Proposed method for purifying aluminum employs one-step vacuum distillation. Raw material for process impure aluminum produced in electrolysis of aluminum ore. Impure metal melted in vacuum. Since aluminum has much higher vapor pressure than other constituents, boils off and condenses on nearby cold surfaces in proportions much greater than those of other constituents.
Vacuum infusion method for woven carbon/Kevlar reinforced hybrid composite
NASA Astrophysics Data System (ADS)
Hashim, N.; Majid, D. L.; Uda, N.; Zahari, R.; Yidris, N.
2017-12-01
The vacuum assisted resin transfer moulding (VaRTM) or Vacuum Infusion (VI) is one of the fabrication methods used for composite materials. Compared to other methods, this process costs lower than using prepregs because it does not need to use the autoclave to cure. Moreover, composites fabricated using this VI method exhibit superior mechanical properties than those made through hand layup process. In this study, the VI method is used in fabricating woven carbon/Kevlar fibre cloth with epoxy matrix. This paper reports the detailed methods on fabricating the hybrid composite using VI process and several precautions that need to be taken to avoid any damage to the properties of the composite material. The result highlights that the successfully fabricated composite has approximately 60% of fibres weight fraction. Since the composites produced by the VI process have a higher fibre percentage, this process should be considered for composites used in applications that are susceptible to the conditions where the fibres need to be the dominant element such as in tension loading.
Dual shell pressure balanced vessel
Fassbender, Alexander G.
1992-01-01
A dual-wall pressure balanced vessel for processing high viscosity slurries at high temperatures and pressures having an outer pressure vessel and an inner vessel with an annular space between the vessels pressurized at a pressure slightly less than or equivalent to the pressure within the inner vessel.
Breakdown-Resistant RF Connectors for Vacuum
NASA Technical Reports Server (NTRS)
Caro, Edward R.; Bonazza, Walter J.
1987-01-01
Resilient inserts compensate for insulation shrinkage. Coaxial-cable connector for radio-frequency (RF) energy resists electrical breakdown in vacuum. Used on RF equipment in vacuum chambers as well as in spaceborne radar and communication gear.
A versatile approach to vacuum injection casting for materials research and development.
Xu, Donghua; Xu, Yifan
2017-03-01
Vacuum injection casting (VIC) is important for research and development (R&D) of materials that are prone to oxidation at high temperatures, particularly metals and metallic alloys (e.g., metallic glasses and high entropy alloys). VIC in R&D laboratories often involves initial melting/alloying in a prior step, transporting the sample to a dedicated vacuum chamber, re-melting the sample in a quartz tube, and finally injecting the melt with an inert gas to a dedicated mold. Here we present a new approach to laboratory VIC that requires no sample transfer (for a variety of materials), no dedicated vacuum chamber/space nor dedicated mold, and hence provides more versatility and higher efficiency and yet lowers the capital equipment cost. Our approach takes advantage of the exceptional portability, thermal and chemical stability, and thermoplastic processability of quartz glass and uses quartz tubes for all the melting, re-melting, injection casting, and molding. In addition, our approach includes oxygen gettering to remove residual oxygen for all the steps and allows for slow or fast cooling (e.g., water quenching) upon injection. This paper focuses on the design, the procedures, and the versatile features of this new approach while also demonstrating the practical implementation of this approach and computational modeling of the heat transfer and the cooling rates for two exemplary cases. The new approach is expected to bring notable expedition to sample fabrication and materials discovery, as well as wider adoption of vacuum injection casting in materials science and condensed matter physics research laboratories.
A versatile approach to vacuum injection casting for materials research and development
NASA Astrophysics Data System (ADS)
Xu, Donghua; Xu, Yifan
2017-03-01
Vacuum injection casting (VIC) is important for research and development (R&D) of materials that are prone to oxidation at high temperatures, particularly metals and metallic alloys (e.g., metallic glasses and high entropy alloys). VIC in R&D laboratories often involves initial melting/alloying in a prior step, transporting the sample to a dedicated vacuum chamber, re-melting the sample in a quartz tube, and finally injecting the melt with an inert gas to a dedicated mold. Here we present a new approach to laboratory VIC that requires no sample transfer (for a variety of materials), no dedicated vacuum chamber/space nor dedicated mold, and hence provides more versatility and higher efficiency and yet lowers the capital equipment cost. Our approach takes advantage of the exceptional portability, thermal and chemical stability, and thermoplastic processability of quartz glass and uses quartz tubes for all the melting, re-melting, injection casting, and molding. In addition, our approach includes oxygen gettering to remove residual oxygen for all the steps and allows for slow or fast cooling (e.g., water quenching) upon injection. This paper focuses on the design, the procedures, and the versatile features of this new approach while also demonstrating the practical implementation of this approach and computational modeling of the heat transfer and the cooling rates for two exemplary cases. The new approach is expected to bring notable expedition to sample fabrication and materials discovery, as well as wider adoption of vacuum injection casting in materials science and condensed matter physics research laboratories.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-28
... Vessel Operator Financial Responsibility Requirements for Non-Performance of Transportation AGENCY..., 2011, the Commission issued its Notice of Proposed Rulemaking (NPRM) to update its financial... cost of financial responsibility coverage because of the use of alternative coverage options. However...
NASA Astrophysics Data System (ADS)
Radtke, W.
1992-10-01
Cylindrical liners made of Al 2219 may be spinrolled if both recrystallization and metastable precipitates can be avoided during forging or preparatory heat treatment. So welding is to be limited to circumferential joints. Pore-free welds are attainable immediately after hydroxide layer removal by diamond cutting without grease application. The EB vacuum is favorable to porosity suppression. A complete heat treatment of the liner incorporating solutionizing, water quenching and ageing leads to 100 percent weld efficiency. Pressure stabilization avoids buckling. Subsequent carbon fiber winding, curing and plastic prestressing of the liner results in an efficient high pressure vessel for hydrogen service.
Breather cloth for vacuum curing
NASA Technical Reports Server (NTRS)
Reed, M. W.
1979-01-01
Finely-woven nylon cloth that has been treated with Teflon improves vacuum adhesive bonding of coatings to substrates. Cloth is placed over coating; entire assembly, including substrate, coating, and cloth, is placed in plastic vacuum bag for curing. Cloth allows coating to "breathe" when bag is evacuated. Applications include bonding film coatings to solar concentrators and collectors.
Vacuum Gas Tungsten Arc Welding
NASA Technical Reports Server (NTRS)
Weeks, J. L.; Todd, D. T.; Wooten, J. R.
1997-01-01
A two-year program investigated vacuum gas tungsten arc welding (VGTAW) as a method to modify or improve the weldability of normally difficult-to-weld materials. After a vacuum chamber and GTAW power supply were modified, several difficult-to-weld materials were studied and key parameters developed. Finally, Incoloy 903 weld overlays were produced without microfissures.
Yesil, Mustafa; Kasler, David R; Huang, En; Yousef, Ahmed E
2017-07-01
Foodborne disease outbreaks associated with the consumption of fresh produce pose a threat to public health, decrease consumer confidence in minimally processed foods, and negatively impact the sales of these commodities. The aim of the study was to determine the influence of population size of inoculated pathogen on its inactivation by gaseous ozone treatment during vacuum cooling. Spinach leaves were spot inoculated with Escherichia coli O157:H7 at approximate initial populations of 10 8 , 10 7 , and 10 5 CFU/g. Inoculated leaves were vacuum cooled (28.5 inHg; 4°C) in a custom-made vessel and then were subjected to a gaseous ozone treatment under the following conditions: 1.5 g of ozone per kg of gas mixture, vessel pressure at 10 lb/in 2 gauge, 94 to 98% relative humidity, and 30 min of holding time at 9°C. Treatment of the leaves, having the aforementioned inocula, decreased E. coli populations by 0.2, 2.1, and 2.8 log CFU/g, respectively, compared with the inoculated untreated controls. Additionally, spinach leaves were inoculated at 1.4 × 10 3 CFU/g, which approximates natural contamination level, and the small populations remaining after ozone treatment were quantified using the most-probable-number (MPN) method. Vacuum and ozone sequential treatment decreased this E. coli O157:H7 population to <3 MPN/g (i.e., greater than 3-log reduction). Resulting log reductions were greater (P < 0.05) at the lower rather than the higher inoculum levels. In conclusion, treatment of spinach leaves with gaseous ozone is effective against pathogen loads comparable to those found in naturally contaminated fresh produce, but efficacy decreases as inoculum level increases.
NASA Technical Reports Server (NTRS)
Knoell, A. C.
1972-01-01
Computer program has been specifically developed to handle, in an efficient and cost effective manner, planar wound pressure vessels fabricated of either boron-epoxy or graphite-epoxy advanced composite materials.
Apparatus For Metal/Inert-Gas Welding In Vacuum
NASA Technical Reports Server (NTRS)
Stocks, C. O.
1994-01-01
Metal/inert-gas welding-torch assembly operates in vacuum. Plasma generated in interior chamber and focused onto workpiece in vacuum. Pinch rollers feed wire to weld puddle. Controlled flow of plasma reduces dispersal in vacuum, preventing extinction.
TFTR diagnostic vacuum controller
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olsen, D.; Persons, R.
1981-01-01
The TFTR diagnostic vacuum controller (DVC) provides in conjunction with the Central Instrumentation Control and Data Acquisition System (CICADA), control and monitoring for the pumps, valves and gauges associated with each individual diagnostic vacuum system. There will be approximately 50 systems on TFTR. Two standard versions of the controller (A and B) wil be provided in order to meet the requirements of two diagnostic manifold arrangements. All pump and valve sequencing, as well as protection features, will be implemented by the controller.
Improved Methodology for Developing Cost Uncertainty Models for Naval Vessels
2009-04-22
Deegan , 2007). Risk cannot be assessed with a point estimate, as it represents a single value that serves as a best guess for the parameter to be...or stakeholders ( Deegan & Fields, 2007). This paper analyzes the current NAVSEA 05C Cruiser (CG(X)) probabilistic cost model including data...provided by Mr. Chris Deegan and his CG(X) analysts. The CG(X) model encompasses all factors considered for cost of the entire program, including
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-23
... Collection; Comment Request; Foreign Fishing Vessel Permits, Vessel, and Gear Identification, and Reporting..., vessels and certain gear be marked for identification purposes, and for permit holders to report their... information for a permit, mark their vessels and gear, or submit information about their fishing activities...
Wang, Lingling; Sun, Lingbin; Wang, Lijun; Chen, Huifang; Ouyang, Xue; Qiu, Huiling
2015-11-01
The aim of this study was to determine the feasibility and effects of temporary bilateral uterine artery occlusion with silicone tubing on blood loss during vacuum aspiration of cesarean scar pregnancies (CSP). Six patients with CSP underwent removal of gestational masses via vacuum aspiration. At the beginning of the procedure, all patients underwent laparoscopic temporary bilateral uterine artery occlusion with tubing. The main measurements were the operating time, operative blood loss, Doppler examination of the uterine arteries, and complications of procedure. The median operation time was 99 min, the median time needed to put the tubing in place (the time from the opening of the retroperitoneum to positioning of the tubing) was 45.5 min and the median time of bilateral uterine artery occlusion with tubing was 32.5 min. The median blood loss was 97.5 mL, and none of the patients required blood transfusion. Doppler examination showed no difference in the pre- and postoperative resistance or pulsatility indices of the uterine vessels. There were no conspicuous complications. The serum ß-human chorionic gonadotrophin level decreased to normal within 14-27 days after the operation. Laparoscopic temporary bilateral uterine artery occlusion with silicone tubing is an effective, minimally invasive procedure for reducing blood loss during vacuum aspiration in patients with CSP. © 2015 Japan Society of Obstetrics and Gynecology.
Fate of electroweak vacuum during preheating
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ema, Yohei; Mukaida, Kyohei; Nakayama, Kazunori
2016-10-28
Our electroweak vacuum may be metastable in light of the current experimental data of the Higgs/top quark mass. If this is really the case, high-scale inflation models require a stabilization mechanism of our vacuum during inflation. A possible candidate is the Higgs-inflaton/-curvature coupling because it induces an additional mass term to the Higgs during the slow roll regime. However, after inflation, the additional mass term oscillates, and it can destabilize our electroweak vacuum via production of large Higgs fluctuations during the inflaton oscillation era. In this paper, we study whether or not the Higgs-inflaton/-curvature coupling can save our vacuum bymore » properly taking account of Higgs production during the preheating stage. We put upper bounds on the Higgs-inflaton and -curvature couplings, and discuss possible dynamics that might relax them.« less
Cryostat including heater to heat a target
Pehl, Richard H.; Madden, Norman W.; Malone, Donald F.
1990-01-01
A cryostat is provided which comprises a vacuum vessel; a target disposed within the vacuum vessel; a heat sink disposed within the vacuum vesssel for absorbing heat from the detector; a cooling mechanism for cooling the heat sink; a cryoabsorption mechanism for cryoabsorbing residual gas within the vacuum vessel; and a heater for maintaining the target above a temperature at which the residual gas is cryoabsorbed in the course of cryoabsorption of the residual gas by the cryoabsorption mechanism.
Industrializing Offshore Wind Power with Serial Assembly and Lower-cost Deployment - Final Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kempton, Willett
A team of engineers and contractors has developed a method to move offshore wind installation toward lower cost, faster deployment, and lower environmental impact. A combination of methods, some incremental and some breaks from past practice, interact to yield multiple improvements. Three designs were evaluated based on detailed engineering: 1) a 5 MW turbine on a jacket with pin piles (base case), 2) a 10 MW turbine on a conventional jacket with pin piles, assembled at sea, and 3) a 10 MW turbine on tripod jacket with suction buckets (caissons) and with complete turbine assembly on-shore. The larger turbine, assemblymore » ashore, and the use of suction buckets together substantially reduce capital cost of offshore wind projects. Notable capital cost reductions are: changing from 5 MW to 10 MW turbine, a 31% capital cost reduction, and assembly on land then single-piece install at sea an additional 9% capital cost reduction. An estimated Design 4) estimates further cost reduction when equipment and processes of Design 3) are optimized, rather than adapted to existing equipment and process. Cost of energy for each of the four Designs are also calculated, yielding approximately the same percentage reductions. The methods of Design 3) analyzed here include accepted structures such as suction buckets used in new ways, innovations conceived but previously without engineering and economic validation, combined with new methods not previously proposed. Analysis of Designs 2) and 3) are based on extensive engineering calculations and detailed cost estimates. All design methods can be done with existing equipment, including lift equipment, ports and ships (except that design 4 assumes a more optimized ship). The design team consists of experienced offshore structure designers, heavy lift engineers, wind turbine designers, vessel operators, and marine construction contractors. Comparing the methods based on criteria of cost and deployment speed, the study selected the
NASA Technical Reports Server (NTRS)
Wingett, Paul (Inventor)
2001-01-01
A mounting assembly for mounting a composite pressure vessel to a vehicle includes a saddle having a curved surface extending between two pillars for receiving the vessel. The saddle also has flanged portions which can be bolted to the vehicle. Each of the pillars has hole in which is mounted the shaft portion of an attachment member. A resilient member is disposed between each of the shaft portions and the holes and loaded by a tightening nut. External to the holes, each of the attachment members has a head portion to which a steel band is attached. The steel band circumscribes the vessel and translates the load on the springs into a clamping force on the vessel. As the vessel expands and contracts, the resilient members expand and contract so that the clamping force applied by the band to the vessel remains constant.
NASA Technical Reports Server (NTRS)
Dever, Joyce A.; Degroh, Kim K.; Stidham, Curtis R.; Stueber, Thomas J.; Dever, Therese M.; Rodriguez, Elvin; Terlep, Judith A.
1992-01-01
In order to assess the low Earth orbit (LEO) durability of candidate space materials, it is necessary to use ground laboratory facilities which provide LEO environmental effects. A facility combining vacuum thermal cycling and vacuum ultraviolet (VUV) radiation has been designed and constructed at NASA Lewis Research Center for this purpose. This facility can also be operated without the VUV lamps. An additional facility can be used to provide VUV exposure only. By utilizing these facilities, followed by atomic oxygen exposure in an RF plasma asher, the effects of the individual vacuum thermal cycling and VUV environments can be compared to the effect of the combined vacuum thermal cycling/VUV environment on the atomic oxygen durability of materials. The synergistic effects of simulated LEO environmental conditions on materials were evaluated by first exposing materials to vacuum thermal cycling, VUV, and vacuum thermal cycling/VUV environments followed by exposure to atomic oxygen in an RP plasma asher. Candidate space power materials such as atomic oxygen protected polyimides and solar concentrator mirrors were evaluated using these facilities. Characteristics of the Vacuum Thermal Cycling/VUV Exposure Facility which simulates the temperature sequences and solar ultraviolet radiation exposure that would be experienced by a spacecraft surface in LEO are discussed. Results of durability evaluations of some candidate space power materials to the simulated LEO environmental conditions will also be discussed. Such results have indicated that for some materials, atomic oxygen durability is affected by previous exposure to thermal cycling and/or VUV exposure.
Nearly Seamless Vacuum-Insulated Boxes
NASA Technical Reports Server (NTRS)
Stepanian, Christopher J.; Ou, Danny; Hu, Xiangjun
2010-01-01
A design concept, and a fabrication process that would implement the design concept, have been proposed for nearly seamless vacuum-insulated boxes that could be the main structural components of a variety of controlled-temperature containers, including common household refrigerators and insulating containers for shipping foods. In a typical case, a vacuum-insulated box would be shaped like a rectangular parallelepiped conventional refrigerator box having five fully closed sides and a hinged door on the sixth side. Although it is possible to construct the five-closed-side portion of the box as an assembly of five unitary vacuum-insulated panels, it is not desirable to do so because the relatively high thermal conductances of the seams between the panels would contribute significant amounts of heat leakage, relative to the leakage through the panels themselves. In contrast, the proposal would make it possible to reduce heat leakage by constructing the five-closed-side portion of the box plus the stationary portion (if any) of the sixth side as a single, seamless unit; the only remaining seam would be the edge seal around the door. The basic cross-sectional configuration of each side of a vacuum-insulated box according to the proposal would be that of a conventional vacuum-insulated panel: a low-density, porous core material filling a partially evacuated space between face sheets. However, neither the face sheets nor the core would be conventional. The face sheets would be opposite sides of a vacuum bag. The core material would be a flexible polymer-modified silica aerogel of the type described in Silica/Polymer and Silica/Polymer/Fiber Composite Aero - gels (MSC-23736) in this issue of NASA Tech Briefs. As noted in that article, the stiffness of this core material against compression is greater than that of prior aerogels. This is an important advantage because it translates to greater retention of thickness and, hence, of insulation performance when pressure is
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stettenheim, Joel
Norwich Technologies (NT) is developing a disruptively superior solar field for trough concentrating solar power (CSP). Troughs are the leading CSP technology (85% of installed capacity), being highly deployable and similar to photovoltaic (PV) systems for siting. NT has developed the SunTrap receiver, a disruptive alternative to vacuum-tube concentrating solar power (CSP) receivers, a market currently dominated by the Schott PTR-70. The SunTrap receiver will (1) operate at higher temperature (T) by using an insulated, recessed radiation-collection system to overcome the energy losses that plague vacuum-tube receivers at high T, (2) decrease acquisition costs via simpler structure, and (3) dramaticallymore » increase reliability by eliminating vacuum. It offers comparable optical efficiency with thermal loss reduction from ≥ 26% (at presently standard T) to ≥ 55% (at high T), lower acquisition costs, and near-zero O&M costs.« less
Benson, D.K.; Potter, T.F.
1993-01-05
An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially point'' or line'' contacts with the metal wall sheets. In the case of monolithic spacers that form line'' contacts, two such spacers with the line contacts running perpendicular to each other form effectively point'' contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.
Benson, David K.; Potter, Thomas F.
1993-01-01
An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially "point" or "line" contacts with the metal wall sheets. In the case of monolithic spacers that form "line" contacts, two such spacers with the line contacts running perpendicular to each other form effectively "point" contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.
Winter, S; Smith, A; Lappin, D; McDonagh, G; Kirk, B
2017-12-01
Dental handpieces are required to be sterilized between patient use. Vacuum steam sterilization processes with fractionated pre/post-vacuum phases or unique cycles for specified medical devices are required for hollow instruments with internal lumens to assure successful air removal. Entrapped air will compromise achievement of required sterilization conditions. Many countries and professional organizations still advocate non-vacuum sterilization processes for these devices. To investigate non-vacuum downward/gravity displacement, type-N steam sterilization of dental handpieces, using thermometric methods to measure time to achieve sterilization temperature at different handpiece locations. Measurements at different positions within air turbines were undertaken with thermocouples and data loggers. Two examples of widely used UK benchtop steam sterilizers were tested: a non-vacuum benchtop sterilizer (Little Sister 3; Eschmann, Lancing, UK) and a vacuum benchtop sterilizer (Lisa; W&H, Bürmoos, Austria). Each sterilizer cycle was completed with three handpieces and each cycle in triplicate. A total of 140 measurements inside dental handpiece lumens were recorded. The non-vacuum process failed (time range: 0-150 s) to reliably achieve sterilization temperatures within the time limit specified by the international standard (15 s equilibration time). The measurement point at the base of the handpiece failed in all test runs (N = 9) to meet the standard. No failures were detected with the vacuum steam sterilization type B process with fractionated pre-vacuum and post-vacuum phases. Non-vacuum downward/gravity displacement, type-N steam sterilization processes are unreliable in achieving sterilization conditions inside dental handpieces, and the base of the handpiece is the site most likely to fail. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-27
... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Proposed Information Collection; Comment Request; Permitting, Vessel Identification, and Vessel Monitoring System Requirements for... satellite- based vessel monitoring system (VMS). This collection of information is needed for permit...
Using vessels as artificial reefs is an option for disposal. Artificial reefs serve to benefit the environment. Vessel-to-reef projects can follow the best management practices guidance. Guidance are provided for how to clean up vessels for use as reefs.
Study on convection improvement of standard vacuum tube
NASA Astrophysics Data System (ADS)
He, J. H.; Du, W. P.; Qi, R. R.; He, J. X.
2017-11-01
For the standard all-glass vacuum tube collector, enhancing the vacuum tube axial natural convection can improve its thermal efficiency. According to the study of the standard all-glass vacuum tube, three kinds of guide plates which can inhibit the radial convection and increase axial natural convection are designed, and theory model is established. Experiments were carried out on vacuum tubes with three types of baffles and standard vacuum tubes without the improvement. The results show that T-type guide plate is better than that of Y-type guide plate on restraining convection and increasing axial radial convection effect, Y type is better than that of flat plate type, all guide plates are better than no change; the thermal efficiency of the tube was 2.6% higher than that of the unmodified standard vacuum tube. The efficiency of the system in the experiment can be increased by 3.1%.
21 CFR 864.9125 - Vacuum-assisted blood collection system.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...
21 CFR 864.9125 - Vacuum-assisted blood collection system.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...
21 CFR 864.9125 - Vacuum-assisted blood collection system.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...
21 CFR 864.9125 - Vacuum-assisted blood collection system.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...
21 CFR 864.9125 - Vacuum-assisted blood collection system.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...
33 CFR 90.3 - Pushing vessel and vessel being pushed: Composite unit.
Code of Federal Regulations, 2010 CFR
2010-07-01
... pushed: Composite unit. 90.3 Section 90.3 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... vessel being pushed: Composite unit. Rule 24(b) of the Inland Rules states that when a pushing vessel and a vessel being pushed ahead are rigidly connected in a composite unit, they are regarded as a power...
CHF Enhancement by Vessel Coating for External Reactor Vessel Cooling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fan-Bill Cheung; Joy L. Rempe
2004-06-01
In-vessel retention (IVR) is a key severe accident management (SAM) strategy that has been adopted by some operating nuclear power plants and advanced light water reactors (ALWRs). One viable means for IVR is the method of external reactor vessel cooling (ERVC) by flooding of the reactor cavity during a severe accident. As part of a joint Korean – United States International Nuclear Energy Research Initiative (K-INERI), an experimental study has been conducted to investigate the viability of using an appropriate vessel coating to enhance the critical heat flux (CHF) limits during ERVC. Toward this end, transient quenching and steady-state boilingmore » experiments were performed in the SBLB (Subscale Boundary Layer Boiling) facility at Penn State using test vessels with micro-porous aluminum coatings. Local boiling curves and CHF limits were obtained in these experiments. When compared to the corresponding data without coatings, substantial enhancement in the local CHF limits for the case with surface coatings was observed. Results of the steady state boiling experiments showed that micro-porous aluminum coatings were very durable. Even after many cycles of steady state boiling, the vessel coatings remained rather intact, with no apparent changes in color or structure. Moreover, the heat transfer performance of the coatings was found to be highly desirable with an appreciable CHF enhancement in all locations on the vessel outer surface but with very little effect of aging.« less
Radiant vessel auxiliary cooling system
Germer, John H.
1987-01-01
In a modular liquid-metal pool breeder reactor, a radiant vessel auxiliary cooling system is disclosed for removing the residual heat resulting from the shutdown of a reactor by a completely passive heat transfer system. A shell surrounds the reactor and containment vessel, separated from the containment vessel by an air passage. Natural circulation of air is provided by air vents at the lower and upper ends of the shell. Longitudinal, radial and inwardly extending fins extend from the shell into the air passage. The fins are heated by radiation from the containment vessel and convect the heat to the circulating air. Residual heat from the primary reactor vessel is transmitted from the reactor vessel through an inert gas plenum to a guard or containment vessel designed to contain any leaking coolant. The containment vessel is conventional and is surrounded by the shell.
Blood vessel rupture by cavitation
Chen, Hong; Brayman, Andrew A.; Bailey, Michael R.
2011-01-01
Cavitation is thought to be one mechanism for vessel rupture during shock wave lithotripsy treatment. However, just how cavitation induces vessel rupture remains unknown. In this work, a high-speed photomicrography system was set up to directly observe the dynamics of bubbles inside blood vessels in ex vivo rat mesenteries. Vascular rupture correlating to observed bubble dynamics were examined by imaging bubble extravasation and dye leakage. The high-speed images show that bubble expansion can cause vessel distention, and bubble collapse can lead to vessel invagination. Liquid jets were also observed to form. Our results suggest that all three mechanisms, vessel distention, invagination and liquid jets, can contribute to vessel rupture. PMID:20680255
14 CFR 25.1433 - Vacuum systems.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Vacuum systems. 25.1433 Section 25.1433 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There...
50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.
Code of Federal Regulations, 2010 CFR
2010-10-01
... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...
50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.
Code of Federal Regulations, 2013 CFR
2013-10-01
... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...
50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.
Code of Federal Regulations, 2011 CFR
2011-10-01
... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...
50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.
Code of Federal Regulations, 2014 CFR
2014-10-01
... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...
50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.
Code of Federal Regulations, 2012 CFR
2012-10-01
... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...
46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.
Code of Federal Regulations, 2013 CFR
2013-10-01
... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...
46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.
Code of Federal Regulations, 2010 CFR
2010-10-01
... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...
46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.
Code of Federal Regulations, 2014 CFR
2014-10-01
... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...
46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.
Code of Federal Regulations, 2012 CFR
2012-10-01
... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...
46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.
Code of Federal Regulations, 2011 CFR
2011-10-01
... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...
Plates for vacuum thermal fusion
Davidson, James C.; Balch, Joseph W.
2002-01-01
A process for effectively bonding arbitrary size or shape substrates. The process incorporates vacuum pull down techniques to ensure uniform surface contact during the bonding process. The essence of the process for bonding substrates, such as glass, plastic, or alloys, etc., which have a moderate melting point with a gradual softening point curve, involves the application of an active vacuum source to evacuate interstices between the substrates while at the same time providing a positive force to hold the parts to be bonded in contact. This enables increasing the temperature of the bonding process to ensure that the softening point has been reached and small void areas are filled and come in contact with the opposing substrate. The process is most effective where at least one of the two plates or substrates contain channels or grooves that can be used to apply vacuum between the plates or substrates during the thermal bonding cycle. Also, it is beneficial to provide a vacuum groove or channel near the perimeter of the plates or substrates to ensure bonding of the perimeter of the plates or substrates and reduce the unbonded regions inside the interior region of the plates or substrates.
33 CFR 82.3 - Pushing vessel and vessel being pushed: Composite unit.
Code of Federal Regulations, 2010 CFR
2010-07-01
... pushed: Composite unit. 82.3 Section 82.3 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... vessel being pushed: Composite unit. Rule 24(b) of the 72 COLREGS states that when a pushing vessel and a vessel being pushed ahead are rigidly connected in a composite unit, they are regarded as a power-driven...
Researches on Position Detection for Vacuum Switch Electrode
NASA Astrophysics Data System (ADS)
Dong, Huajun; Guo, Yingjie; Li, Jie; Kong, Yihan
2018-03-01
Form and transformation character of vacuum arc is important influencing factor on the vacuum switch performance, and the dynamic separations of electrode is the chief effecting factor on the transformation of vacuum arcs forms. Consequently, how to detect the position of electrode to calculate the separations in the arcs image is of great significance. However, gray level distribution of vacuum arcs image isn’t even, the gray level of burning arcs is high, but the gray level of electrode is low, meanwhile, the forms of vacuum arcs changes sharply, the problems above restrict electrode position detection precisely. In this paper, algorithm of detecting electrode position base on vacuum arcs image was proposed. The digital image processing technology was used in vacuum switch arcs image analysis, the upper edge and lower edge were detected respectively, then linear fitting was done using the result of edge detection, the fitting result was the position of electrode, thus, accurate position detection of electrode was realized. From the experimental results, we can see that: algorithm described in this paper detected upper and lower edge of arcs successfully and the position of electrode was obtained through calculation.
Advanced Photon Source accelerator ultrahigh vacuum guide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, C.; Noonan, J.
1994-03-01
In this document the authors summarize the following: (1) an overview of basic concepts of ultrahigh vacuum needed for the APS project, (2) a description of vacuum design and calculations for major parts of APS, including linac, linac waveguide, low energy undulator test line, positron accumulator ring (PAR), booster synchrotron ring, storage ring, and insertion devices, and (3) cleaning procedures of ultrahigh vacuum (UHV) components presently used at APS.
Ceramic vacuum tubes for geothermal well logging
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kelly, R.D.
1977-01-01
Useful design data acquired in the evaluation of ceramic vacuum tubes for the development of a 500/sup 0/C instrumentation amplifier are presented. The general requirements for ceramic vacuum tubes are discussed for application to the development of high temperature well logs. Commercially available tubes are described and future contract activities that specifically relate to ceramic vacuum tubes are detailed. Supplemental data are presented in the appendix.
46 CFR 105.10-20 - Pressure vacuum relief valve.
Code of Federal Regulations, 2011 CFR
2011-10-01
... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2011-10-01 2011-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...
46 CFR 105.10-20 - Pressure vacuum relief valve.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2010-10-01 2010-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...
46 CFR 105.10-20 - Pressure vacuum relief valve.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2014-10-01 2014-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...
46 CFR 105.10-20 - Pressure vacuum relief valve.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2012-10-01 2012-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...
46 CFR 105.10-20 - Pressure vacuum relief valve.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2013-10-01 2013-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...
7 CFR 58.913 - Evaporators and vacuum pans.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 3 2010-01-01 2010-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...
7 CFR 58.913 - Evaporators and vacuum pans.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 3 2014-01-01 2014-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...
7 CFR 58.913 - Evaporators and vacuum pans.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 3 2011-01-01 2011-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...
7 CFR 58.913 - Evaporators and vacuum pans.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 3 2013-01-01 2013-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...
7 CFR 58.913 - Evaporators and vacuum pans.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 3 2012-01-01 2012-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...
A computational algorithm addressing how vessel length might depend on vessel diameter
Jing Cai; Shuoxin Zhang; Melvin T. Tyree
2010-01-01
The objective of this method paper was to examine a computational algorithm that may reveal how vessel length might depend on vessel diameter within any given stem or species. The computational method requires the assumption that vessels remain approximately constant in diameter over their entire length. When this method is applied to three species or hybrids in the...
Vacuum coupling of rotating superconducting rotor
Shoykhet, Boris A.; Zhang, Burt Xudong; Driscoll, David Infante
2003-12-02
A rotating coupling allows a vacuum chamber in the rotor of a superconducting electric motor to be continually pumped out. The coupling consists of at least two concentric portions, one of which is allowed to rotate and the other of which is stationary. The coupling is located on the non-drive end of the rotor and is connected to a coolant supply and a vacuum pump. The coupling is smaller in diameter than the shaft of the rotor so that the shaft can be increased in diameter without having to increase the size of the vacuum seal.
Dissolver vessel bottom assembly
Kilian, Douglas C.
1976-01-01
An improved bottom assembly is provided for a nuclear reactor fuel reprocessing dissolver vessel wherein fuel elements are dissolved as the initial step in recovering fissile material from spent fuel rods. A shock-absorbing crash plate with a convex upper surface is disposed at the bottom of the dissolver vessel so as to provide an annular space between the crash plate and the dissolver vessel wall. A sparging ring is disposed within the annular space to enable a fluid discharged from the sparging ring to agitate the solids which deposit on the bottom of the dissolver vessel and accumulate in the annular space. An inlet tangential to the annular space permits a fluid pumped into the annular space through the inlet to flush these solids from the dissolver vessel through tangential outlets oppositely facing the inlet. The sparging ring is protected against damage from the impact of fuel elements being charged to the dissolver vessel by making the crash plate of such a diameter that the width of the annular space between the crash plate and the vessel wall is less than the diameter of the fuel elements.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Webber, Nels W.
Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.Themore » project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.« less
Low-cost far infrared bolometer camera for automotive use
NASA Astrophysics Data System (ADS)
Vieider, Christian; Wissmar, Stanley; Ericsson, Per; Halldin, Urban; Niklaus, Frank; Stemme, Göran; Källhammer, Jan-Erik; Pettersson, Håkan; Eriksson, Dick; Jakobsen, Henrik; Kvisterøy, Terje; Franks, John; VanNylen, Jan; Vercammen, Hans; VanHulsel, Annick
2007-04-01
A new low-cost long-wavelength infrared bolometer camera system is under development. It is designed for use with an automatic vision algorithm system as a sensor to detect vulnerable road users in traffic. Looking 15 m in front of the vehicle it can in case of an unavoidable impact activate a brake assist system or other deployable protection system. To achieve our cost target below €100 for the sensor system we evaluate the required performance and can reduce the sensitivity to 150 mK and pixel resolution to 80 x 30. We address all the main cost drivers as sensor size and production yield along with vacuum packaging, optical components and large volume manufacturing technologies. The detector array is based on a new type of high performance thermistor material. Very thin Si/SiGe single crystal multi-layers are grown epitaxially. Due to the resulting valence barriers a high temperature coefficient of resistance is achieved (3.3%/K). Simultaneously, the high quality crystalline material provides very low 1/f-noise characteristics and uniform material properties. The thermistor material is transferred from the original substrate wafer to the read-out circuit using adhesive wafer bonding and subsequent thinning. Bolometer arrays can then be fabricated using industry standard MEMS process and materials. The inherently good detector performance allows us to reduce the vacuum requirement and we can implement wafer level vacuum packaging technology used in established automotive sensor fabrication. The optical design is reduced to a single lens camera. We develop a low cost molding process using a novel chalcogenide glass (GASIR®3) and integrate anti-reflective and anti-erosion properties using diamond like carbon coating.
In-Vacuum Dissociator for Atomic-Hydrogen Masers
NASA Technical Reports Server (NTRS)
Vessot, R. F.
1987-01-01
Thermal control and vacuum sealing achieved while contamination avoided. Simple, relatively inexpensive molecular-hydrogen dissociator for atomic-hydrogen masers used on Earth or in vacuum of space. No air cooling required, and absence of elastomeric O-ring seals prevents contamination. In-vacuum dissociator for atomic hydrogen masers, hydrogen gas in glass dissociator dissociated by radio-frequency signal transmitted from surrounding 3-turn coil. Heat in glass conducted away by contacting metal surfaces.
Vacuum-jacketed transfer line installation technique
NASA Technical Reports Server (NTRS)
Bowers, W. M.
1968-01-01
Rolling-type spacers in the form of steel balls retained in appropriate sleeves affixed at intervals to the exterior of the transfer line facilitate the installation of a vacuum-jacketed line. They act as standoffs to position the transfer line concentrically within the vacuum jacket line.
Thermodynamic performance of multi-stage gradational lead screw vacuum pump
NASA Astrophysics Data System (ADS)
Zhao, Fan; Zhang, Shiwei; Sun, Kun; Zhang, Zhijun
2018-02-01
As a kind of dry mechanical vacuum pump, the twin-screw vacuum pump has an outstanding pumping performance during operation, widely used in the semiconductor industry. Compared with the constant lead screw (CLS) vacuum pump, the gradational lead screw (GLS) vacuum pump is more popularly applied in recent years. Nevertheless, not many comparative studies on the thermodynamic performance of GLS vacuum pump can be found in the literature. Our study focuses on one type of GLS vacuum pump, the multi-stage gradational lead screw (MGLS) vacuum pump, gives a detailed description of its construction and illustrates it with the drawing. Based on the structural analysis, the thermodynamic procedure is divided into four distinctive processes, including sucking process, transferring (compressing) process, backlashing process and exhausting process. The internal mechanism of each process is qualitatively illustrated and the mathematical expressions of seven thermodynamic parameters are given under the ideal situation. The performance curves of MGLS vacuum pump are plotted by MATLAB software and compared with those of the CLS vacuum pump in the same case. The results can well explain why the MGLS vacuum pump has more favorable pumping performance than the CLS vacuum pump in saving energy, reducing noise and heat dissipation.
REVIEWS OF TOPICAL PROBLEMS: Cosmic vacuum
NASA Astrophysics Data System (ADS)
Chernin, Artur D.
2001-11-01
Recent observational studies of distant supernovae have suggested the existence of cosmic vacuum whose energy density exceeds the total density of all the other energy components in the Universe. The vacuum produces the field of antigravity that causes the cosmological expansion to accelerate. It is this accelerated expansion that has been discovered in the observations. The discovery of cosmic vacuum radically changes our current understanding of the present state of the Universe. It also poses new challenges to both cosmology and fundamental physics. Why is the density of vacuum what it is? Why do the densities of the cosmic energy components differ in exact value but agree in order of magnitude? On the other hand, the discovery made at large cosmological distances of hundreds and thousands Mpc provides new insights into the dynamics of the nearby Universe, the motions of galaxies in the local volume of 10 - 20 Mpc where the cosmological expansion was originally discovered.
Source replenishment device for vacuum deposition
Hill, Ronald A.
1988-01-01
A material source replenishment device for use with a vacuum deposition apparatus. The source replenishment device comprises an intermittent motion producing gear arrangement disposed within the vacuum deposition chamber. An elongated rod having one end operably connected to the gearing arrangement is provided with a multiarmed head at the opposite end disposed adjacent the heating element of the vacuum deposition apparatus. An inverted U-shaped source material element is releasably attached to the outer end of each arm member whereby said multiarmed head is moved to locate a first of said material elements above said heating element, whereupon said multiarmed head is lowered to engage said material element with the heating element and further lowered to release said material element on the heating element. After vaporization of said material element, second and subsequent material elements may be provided to the heating element without the need for opening the vacuum deposition apparatus to the atmosphere.
Source replenishment device for vacuum deposition
Hill, R.A.
1986-05-15
A material source replenishment device for use with a vacuum deposition apparatus is described. The source replenishment device comprises an intermittent motion producing gear arrangement disposed within the vacuum deposition chamber. An elongated rod having one end operably connected to the gearing arrangement is provided with a multiarmed head at the opposite end disposed adjacent the heating element of the vacuum deposition apparatus. An inverted U-shaped source material element is releasably attached to the outer end of each arm member whereby said multiarmed head is moved to locate a first of said material elements above said heating element, whereupon said multiarmed head is lowered to engage said material element with the heating element and further lowered to release said material element on the heating element. After vaporization of said material element, second and subsequent material elements may be provided to the heating element without the need for opening the vacuum deposition apparatus to the atmosphere.
Waveguide quantum electrodynamics in squeezed vacuum
NASA Astrophysics Data System (ADS)
You, Jieyu; Liao, Zeyang; Li, Sheng-Wen; Zubairy, M. Suhail
2018-02-01
We study the dynamics of a general multiemitter system coupled to the squeezed vacuum reservoir and derive a master equation for this system based on the Weisskopf-Wigner approximation. In this theory, we include the effect of positions of the squeezing sources which is usually neglected in the previous studies. We apply this theory to a quasi-one-dimensional waveguide case where the squeezing in one dimension is experimentally achievable. We show that while dipole-dipole interaction induced by ordinary vacuum depends on the emitter separation, the two-photon process due to the squeezed vacuum depends on the positions of the emitters with respect to the squeezing sources. The dephasing rate, decay rate, and the resonance fluorescence of the waveguide-QED in the squeezed vacuum are controllable by changing the positions of emitters. Furthermore, we demonstrate that the stationary maximum entangled NOON state for identical emitters can be reached with arbitrary initial state when the center-of-mass position of the emitters satisfies certain conditions.
78 FR 64523 - Agency Information Collection Activities: Vessel Entrance or Clearance Statement
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-29
... respondents or record keepers from the collection of information (a total capital/startup costs and operations... vessel data at time of formal entrance and clearance in U.S. ports. The form allows the master to attest... Responses per Respondent: 22. Estimated Total Annual Responses: 264,000. Estimated Time per Response: 30...
The extension of the thermal-vacuum test optimization program to multiple flights
NASA Technical Reports Server (NTRS)
Williams, R. E.; Byrd, J.
1981-01-01
The thermal vacuum test optimization model developed to provide an approach to the optimization of a test program based on prediction of flight performance with a single flight option in mind is extended to consider reflight as in space shuttle missions. The concept of 'utility', developed under the name of 'availability', is used to follow performance through the various options encountered when the capabilities of reflight and retrievability of space shuttle are available. Also, a 'lost value' model is modified to produce a measure of the probability of a mission's success, achieving a desired utility using a minimal cost test strategy. The resulting matrix of probabilities and their associated costs provides a means for project management to evaluate various test and reflight strategies.
Carbon fiber internal pressure vessels
NASA Technical Reports Server (NTRS)
Simon, R. A.
1973-01-01
Internal pressure vessels were designed; the filament was wound of carbon fibers and epoxy resin and tested to burst. The fibers used were Thornel 400, Thornel 75, and Hercules HTS. Additional vessels with type A fiber were made. Polymeric linears were used, and all burst testing was done at room temperature. The objective was to produce vessels with the highest attainable PbV/W efficiencies. The type A vessels showed the highest average efficiency: 2.56 x 10 to the 6th power cm. Next highest efficiency was with Thornel 400 vessels: 2.21 x 10 to the 6th power cm. These values compare favorably with efficiency values from good quality S-glass vessels, but strains averaged 0.97% or less, which is less than 1/3 the strain of S-glass vessels.
NASA Astrophysics Data System (ADS)
Wilcox, C.; Ford, J.
2016-12-01
Crimes involving fishers impose significant costs on fisheries, managers and national governments. These crimes also lead to unsustainable harvesting practices, as they undermine both knowledge of the status of fisheries stocks and limits on their harvesting. One of the greatest contributors to fisheries crimes globally is transfer of fish catch among vessels, otherwise known as transshipment. While legal transshipment provides economic advantages to vessels by increasing their efficiency, illegal transshipment can allow them to avoid regulations, catch prohibited species, and fish with impunity in prohibited locations such as waters of foreign countries. Despite the presence of a number of monitoring technologies for tracking fishing vessels, transshipment is frequently done clandestinely. Here we present a statistical model for transshipment in a Southeast Asian tuna fishery. We utilize both spatial and temporal information on vessel movement patterns in a statistical model to infer unobserved transshipment events among vessels. We provide a risk analysis framework for forecasting likely transshipment events, based on our analysis of vessel movement patterns. The tools we present are widely applicable to a variety of fisheries and types of tracking data, allowing managers to more effectively screen the large volume of data tracking systems create and quickly identify suspicious behavior.
Sugar maple sap volume increases as vacuum level is increased
Russell S. Walters; H. Clay Smith
1975-01-01
Maple sap yields collected by using plastic tubing with a vacuum pump increased as the vacuum level was increased. Sap volumes collected at the 10- and 15-inch mercury vacuum levels were statistically significantly higher than volumes collected at the 5-inch level. Although the 15-inch vacuum yielded more sap than the 10-inch vacuum, the difference was not...
Outgassing of solid material into vacuum thermal insulation spaces
NASA Technical Reports Server (NTRS)
Wang, Pao-Lien
1994-01-01
Many cryogenic storage tanks use vacuum between inner and outer tank for thermal insulation. These cryogenic tanks also use a radiation shield barrier in the vacuum space to prevent radiation heat transfer. This shield is usually constructed by using multiple wraps of aluminized mylar and glass paper as inserts. For obtaining maximum thermal performance, a good vacuum level must be maintained with the insulation system. It has been found that over a period of time solid insulation materials will vaporize into the vacuum space and the vacuum will degrade. In order to determine the degradation of vacuum, the rate of outgassing of the insulation materials must be determined. Outgassing rate of several insulation materials obtained from literature search were listed in tabular form.
Mass spectrometer vacuum housing and pumping system
Coutts, G.W.; Bushman, J.F.; Alger, T.W.
1996-07-23
A vacuum housing and pumping system is described for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof. 7 figs.
Mass spectrometer vacuum housing and pumping system
Coutts, Gerald W.; Bushman, John F.; Alger, Terry W.
1996-01-01
A vacuum housing and pumping system for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sarantopoulou, E., E-mail: esarant@eie.gr; Stefi, A.; Kollia, Z.
Ultraviolet photons can damage microorganisms, which rarely survive prolonged irradiation. In addition to the need for intact DNA, cell viability is directly linked to the functionality of the cell wall and membrane. In this work, Cladosporium herbarum spore monolayers exhibit high viability (7%) when exposed to 157 nm laser irradiation (412 kJm⁻²) or vacuum-ultraviolet irradiation (110–180 nm) under standard pressure and temperature in a nitrogen atmosphere. Spore viability can be determined by atomic-force microscopy, nano-indentation, mass, μ-Raman and attenuated reflectance Fourier-transform far-infrared spectroscopies and DNA electrophoresis. Vacuum ultraviolet photons cause molecular damage to the cell wall, but radiation resistance inmore » spores arises from the activation of a photon-triggered signaling reaction, expressed via the exudation of intracellular substances, which, in combination with the low penetration depth of vacuum-ultraviolet photons, shields DNA from radiation. Resistance to phototoxicity under standard conditions was assessed, as was resistance to additional environmental stresses, including exposure in a vacuum, under different rates of change of pressure during pumping time and low (10 K) temperatures. Vacuum conditions were far more destructive to spores than vacuum-ultraviolet irradiation, and UV-B photons were two orders of magnitude more damaging than vacuum-ultraviolet photons. The viability of irradiated spores was also enhanced at 10 K. This work, in addition to contributing to the photonic control of the viability of microorganisms exposed under extreme conditions, including decontamination of biological warfare agents, outlines the basis for identifying bio-signaling in vivo using physical methodologies.« less
Vacuum deposition and curing of liquid monomers apparatus
Affinito, John D.
1996-01-01
The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of "standard" polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal or oxide may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.
Development of a MEMS-Scale Turbomachinery Based Vacuum Pump
2012-06-01
MEMS -SCALE TURBOMACHINERY BASED VACUUM PUMP by Michael J. Shea June 2012 Thesis Advisor: Anthony J. Gannon Second Reader...June 2012 3. REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE Development of a MEMS -Scale Turbomachinery Based Vacuum Pump 5...to develop a MEMS scale turbomachinery based vacuum pump. This would allow very high vacuum to be drawn for handheld mass spectroscopy. This
Vacuum system for the SAMURAI spectrometer
NASA Astrophysics Data System (ADS)
Shimizu, Y.; Otsu, H.; Kobayashi, T.; Kubo, T.; Motobayashi, T.; Sato, H.; Yoneda, K.
2013-12-01
The first commissioning experiment of the SAMURAI spectrometer and its beam line was performed in March, 2012. The vacuum system for the SAMURAI spectrometer includes its beam line and the SAMURAI vacuum chamber with the windows for detecting neutrons and charged particles. The window for neutrons was made of stainless steel with a thickness of 3 mm and was designed with a shape of partial cylinder to support itself against the atmospheric pressure. The window for charged particles was of the combination of Kevlar and Mylar with the thickness of 280 and 75 μm, respectively. The pressure in the vacuum system was at a few Pa throughout the commissioning experiment.
Moving characteristics of electrodes for vacuum circuit breaker
NASA Astrophysics Data System (ADS)
Yuan, Shun; Wang, Jimei
1994-05-01
This paper analyzes the effect of the gap of electrodes on the state of vacuum arc by experiment and theory. And the model of vacuum arc is set up. The optimal gap can be deduced from controlling the vacuum arc to be diffusion state, in order to get the optimal moving characteristics of electrodes.
Three stage vacuum system for ultralow temperature installation
NASA Astrophysics Data System (ADS)
Das, N. K.; Pradhan, J.; Naser, Md Z. A.; Mandal, B. Ch; Roy, A.; Kumar, P.; Mallik, C.; Bhandari, R. K.
2012-11-01
We use a three stage vacuum system for developing a dilution fridge at VECC, Kolkata. We aim at achieving a cooling power of 20μW at 100mK for various experiments especially in the field of condensed matter and nuclear physics. The system is essentially composed of four segments-bath cryostat, vacuum system, dilution insert and 3He circulation circuit. Requirement of vacuum system at different stages are different. The vacuum system for cryostat and for internal vacuum chamber located within the helium bath is a common turbo molecular pump backed by scroll pump as to maintain a vacuum ~10-6mbar. For bringing down the temperature of the helium evaporator, we use a high throughput Roots pump backed by a dry pump. The pumping system for 3He distillation chamber (still) requires a high pumping speed, so a turbo drag pump backed by a scroll pump has been installed. As the fridge use precious 3He gas for operation, the entire system has been made to be absolutely leak proof with respect to the 3He gas.
Carbon nanotubes based vacuum gauge
NASA Astrophysics Data System (ADS)
Rudyk, N. N.; Il'in, O. I.; Il'ina, M. V.; Fedotov, A. A.; Klimin, V. S.; Ageev, O. A.
2017-11-01
We have created an ionization type Vacuum gauge with sensor element based on an array of vertically aligned carbon nanotubes. Obtained asymmetrical current-voltage characteristics at different voltage polarity on the electrode with the CNTs. It was found that when applying a negative potential on an electrode with the CNTs, the current in the gap is higher than at a positive potential. In the pressure range of 1 ÷ 103 Torr vacuum gauge sensitivity was 6 mV/Torr (at a current of 4.5·10-5 A) and in the range of 10-5 ÷ 1 Torr was 10 mV/Torr (at a current of 1.3·10-5 A). It is shown that the energy efficiency of vacuum gauge can be increased in the case where electrode with CNT operates as an emitter of electrons.
DOT National Transportation Integrated Search
1999-01-01
Vessel Loading Observations Procedures for P.L. 480, Titles II & III, : Section 416(b) and Food for Progress programs. Notice advises steamship lines and other interested parties that the vessel loading observation (VLO) procedure will continue to be...
NASA Astrophysics Data System (ADS)
Hamada, Yuta; Yamada, Masatoshi
2017-09-01
The null result in the LHC may indicate that the standard model is not drastically modified up to very high scales, such as the GUT/string scale. Having this in the mind, we suggest a novel leptogenesis scenario realized in the false vacuum of the Higgs field. If the Higgs field develops a large vacuum expectation value in the early universe, a lepton number violating process is enhanced, which we use for baryogenesis. To demonstrate the scenario, several models are discussed. For example, we show that the observed baryon asymmetry is successfully generated in the standard model with higher-dimensional operators.
Comparative Evaluation of Vacuum-based Surface Sampling ...
Journal Article Following a biological contamination incident, collection of surface samples is necessary to determine the extent and level of contamination, and to deem an area safe for reentry upon decontamination. Current sampling strategies targeting Bacillus anthracis spores prescribe vacuum-based methods for rough and/or porous surfaces. In this study, four commonly-used B. anthracis spore sampling devices (vacuum socks, 37 mm 0.8 µm MCE filter cassettes, 37 mm 0.3 µm PTFE filter cassettes, and 3MTM forensic filters) were comparatively evaluated for their ability to recover surface-associated spores. The vacuum sock device was evaluated at two sampling speeds (slow and fast), resulting in five total methods evaluated. Aerosolized spores (~105 cm-2) of a surrogate Bacillus species (Bacillus atrophaeus) were allowed to settle onto three material types (concrete, carpet, and upholstery). Ten replicate samples were collected using each vacuum method, from each of the three material types. In addition, stainless steel (i.e., nonporous) surfaces inoculated simultaneously were sampled with pre-moistened wipes. Recoveries from wipes of steel surfaces were utilized to verify the inoculum, and to normalize vacuum-based recoveries across trials. Recovery (CFU cm-2) and relative recovery (vacuum recovery/wipe recovery) were determined for each method and material type. Relative recoveries were compared by one-way and three-way ANOVA. Data analysis by one-
Vacuum energy from noncommutative models
NASA Astrophysics Data System (ADS)
Mignemi, S.; Samsarov, A.
2018-04-01
The vacuum energy is computed for a scalar field in a noncommutative background in several models of noncommutative geometry. One may expect that the noncommutativity introduces a natural cutoff on the ultraviolet divergences of field theory. Our calculations show however that this depends on the particular model considered: in some cases the divergences are suppressed and the vacuum energy is only logarithmically divergent, in other cases they are stronger than in the commutative theory.
Sealed vacuum canister and method for pick-up and containment of material
Stoutenburgh, Roger R.
1996-01-01
A vacuum canister including a housing with a sealed vacuum chamber having a predetermined vacuum pressure therein and a valve having a first port for fluid communication with the vacuum chamber and a second port for receiving at least one of a fluid and a particulate material. The valve is operable between a first position to seal the vacuum chamber and retain the predetermined vacuum within the vacuum chamber, and a second position to access the vacuum chamber to permit vacuum fluid flow through the valve from the second port into the vacuum chamber. In operation of the vacuum canister to pick up material with the valve in the second position, when the second port is located adjacent at least one of a fluid and a particulate material, is effective to displace through the valve at least one of a fluid and a particulate material into the housing. The vacuum canister is desirably suitable for picking up and containing hazardous material such as radioactive material, in which the vacuum canister includes a protective layer of lead having a predetermined thickness that is effective to shield radiation emitted from the radioactive material contained within the housing. Advantageously, the vacuum canister includes a vacuum means for establishing a predetermined vacuum pressure within the vacuum chamber.
Phase-sensitive dual-inversion recovery for accelerated carotid vessel wall imaging.
Bonanno, Gabriele; Brotman, David; Stuber, Matthias
2015-03-01
Dual-inversion recovery (DIR) is widely used for magnetic resonance vessel wall imaging. However, optimal contrast may be difficult to obtain and is subject to RR variability. Furthermore, DIR imaging is time-inefficient and multislice acquisitions may lead to prolonged scanning times. Therefore, an extension of phase-sensitive (PS) DIR is proposed for carotid vessel wall imaging. The statistical distribution of the phase signal after DIR is probed to segment carotid lumens and suppress their residual blood signal. The proposed PS-DIR technique was characterized over a broad range of inversion times. Multislice imaging was then implemented by interleaving the acquisition of 3 slices after DIR. Quantitative evaluation was then performed in healthy adult subjects and compared with conventional DIR imaging. Single-slice PS-DIR provided effective blood-signal suppression over a wide range of inversion times, enhancing wall-lumen contrast and vessel wall conspicuity for carotid arteries. Multislice PS-DIR imaging with effective blood-signal suppression is enabled. A variant of the PS-DIR method has successfully been implemented and tested for carotid vessel wall imaging. This technique removes timing constraints related to inversion recovery, enhances wall-lumen contrast, and enables a 3-fold increase in volumetric coverage at no extra cost in scanning time.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Englund, Carl-Johan; Agåker, Marcus, E-mail: marcus.agaker@physics.uu.se; Fredriksson, Pierre
2015-09-15
A concept that enables in-vacuum continuous variation of the angle between two ports in one plane has been developed and implemented. The vacuum chamber allows for measuring scattering cross sections as a function of scattering angle and is intended for resonant inelastic X-ray scattering experiments. The angle between the ports can be varied in the range of 30°-150°, while the pressure change is less than 2 × 10{sup −10} mbars.
Vacuum-Ultraviolet Photovoltaic Detector.
Zheng, Wei; Lin, Richeng; Ran, Junxue; Zhang, Zhaojun; Ji, Xu; Huang, Feng
2018-01-23
Over the past two decades, solar- and astrophysicists and material scientists have been researching and developing new-generation semiconductor-based vacuum ultraviolet (VUV) detectors with low power consumption and small size for replacing traditional heavy and high-energy-consuming microchannel-detection systems, to study the formation and evolution of stars. However, the most desirable semiconductor-based VUV photovoltaic detector capable of achieving zero power consumption has not yet been achieved. With high-crystallinity multistep epitaxial grown AlN as a VUV-absorbing layer for photogenerated carriers and p-type graphene (with unexpected VUV transmittance >96%) as a transparent electrode to collect excited holes, we constructed a heterojunction device with photovoltaic detection for VUV light. The device exhibits an encouraging VUV photoresponse, high external quantum efficiency (EQE) and extremely fast tempera response (80 ns, 10 4 -10 6 times faster than that of the currently reported VUV photoconductive devices). This work has provided an idea for developing zero power consumption and integrated VUV photovoltaic detectors with ultrafast and high-sensitivity VUV detection capability, which not only allows future spacecraft to operate with longer service time and lower launching cost but also ensures an ultrafast evolution of interstellar objects.
Overview of Fabrication Techniques and Lessons Learned with Accelerator Vacuum Windows
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ader, C. R.; McGee, M. W.; Nobrega, L. E.
Vacuum thin windows have been used in Fermilab's accelerators for decades and typically have been overlooked in terms of their criticality and fragility. Vacuum windows allow beam to pass through while creating a boundary between vacuum and air or high vacuum and low vacuum areas. The design of vacuum windows, including Titanium and Beryllium windows, will be discussed as well as fabrication, testing, and operational concerns. Failure of windows will be reviewed as well as safety approaches to mitigating failures and extending the lifetimes of vacuum windows. Various methods of calculating the strengths of vacuum windows will be explored, includingmore » FEA.« less
Safety shield for vacuum/pressure-chamber windows
NASA Technical Reports Server (NTRS)
Shimansky, R. A.; Spencer, R.
1980-01-01
Optically-clear shatter-resistant safety shield protects workers from implosion and explosion of vacuum and pressure windows. Plastic shield is inexpensive and may be added to vacuum chambers, pressure chambers, and gas-filling systems.
Hadjiiski, Lubomir; Liu, Jordan; Chan, Heang-Ping; Zhou, Chuan; Wei, Jun; Chughtai, Aamer; Kuriakose, Jean; Agarwal, Prachi; Kazerooni, Ella
2016-01-01
The detection of stenotic plaques strongly depends on the quality of the coronary arterial tree imaged with coronary CT angiography (cCTA). However, it is time consuming for the radiologist to select the best-quality vessels from the multiple-phase cCTA for interpretation in clinical practice. We are developing an automated method for selection of the best-quality vessels from coronary arterial trees in multiple-phase cCTA to facilitate radiologist's reading or computerized analysis. Our automated method consists of vessel segmentation, vessel registration, corresponding vessel branch matching, vessel quality measure (VQM) estimation, and automatic selection of best branches based on VQM. For every branch, the VQM was calculated as the average radial gradient. An observer preference study was conducted to visually compare the quality of the selected vessels. 167 corresponding branch pairs were evaluated by two radiologists. The agreement between the first radiologist and the automated selection was 76% with kappa of 0.49. The agreement between the second radiologist and the automated selection was also 76% with kappa of 0.45. The agreement between the two radiologists was 81% with kappa of 0.57. The observer preference study demonstrated the feasibility of the proposed automated method for the selection of the best-quality vessels from multiple cCTA phases.
Extreme-UV lithography vacuum chamber zone seal
Haney, Steven J.; Herron, Donald Joe; Klebanoff, Leonard E.; Replogle, William C.
2001-01-01
Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.
Extreme-UV lithography vacuum chamber zone seal
Haney, Steven J.; Herron, Donald Joe; Klebanoff, Leonard E.; Replogle, William C.
2003-04-08
Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.
Extreme-UV lithography vacuum chamber zone seal
Haney, Steven J.; Herron, Donald Joe; Klebanoff, Leonard E.; Replogle, William C.
2003-04-15
Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.
Vacuum deposition and curing of liquid monomers apparatus
Affinito, J.D.
1996-08-20
The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of ``standard`` polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal or oxide may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface. 3 figs.
Reduction of energy needs for fish harvesting through the use of sails on fishing vessels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1983-05-10
The fishing industry has been hurt by rising fuel costs. This study was undertaken to determine the fuel savings that might occur if sails were used on fishing vessels as an auxiliary means of propulsion. Attention was also paid to vessel safety, crew efficiency and 'come-home' capabilities as they were effected by the use of sails. A boat was designed, built and equipped for sail assisted fishing operations. Data was collected during sea trials, test runs and actual fishing operations. These data were analysed with the help of the Virginia Institute of Marine Science to determine the fuel savings andmore » the economic viability of the configuration. Assessment of the observations of crew performance and vessel safety were analyzed.« less
Measurement of toroidal vessel eddy current during plasma disruption on J-TEXT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, L. J.; Yu, K. X.; Zhang, M., E-mail: zhangming@hust.edu.cn
2016-01-15
In this paper, we have employed a thin, printed circuit board eddy current array in order to determine the radial distribution of the azimuthal component of the eddy current density at the surface of a steel plate. The eddy current in the steel plate can be calculated by analytical methods under the simplifying assumptions that the steel plate is infinitely large and the exciting current is of uniform distribution. The measurement on the steel plate shows that this method has high spatial resolution. Then, we extended this methodology to a toroidal geometry with the objective of determining the poloidal distributionmore » of the toroidal component of the eddy current density associated with plasma disruption in a fusion reactor called J-TEXT. The preliminary measured result is consistent with the analysis and calculation results on the J-TEXT vacuum vessel.« less
Measurement of toroidal vessel eddy current during plasma disruption on J-TEXT.
Liu, L J; Yu, K X; Zhang, M; Zhuang, G; Li, X; Yuan, T; Rao, B; Zhao, Q
2016-01-01
In this paper, we have employed a thin, printed circuit board eddy current array in order to determine the radial distribution of the azimuthal component of the eddy current density at the surface of a steel plate. The eddy current in the steel plate can be calculated by analytical methods under the simplifying assumptions that the steel plate is infinitely large and the exciting current is of uniform distribution. The measurement on the steel plate shows that this method has high spatial resolution. Then, we extended this methodology to a toroidal geometry with the objective of determining the poloidal distribution of the toroidal component of the eddy current density associated with plasma disruption in a fusion reactor called J-TEXT. The preliminary measured result is consistent with the analysis and calculation results on the J-TEXT vacuum vessel.
Microbial analysis of meatballs cooled with vacuum and conventional cooling.
Ozturk, Hande Mutlu; Ozturk, Harun Kemal; Koçar, Gunnur
2017-08-01
Vacuum cooling is a rapid evaporative cooling technique and can be used for pre-cooling of leafy vegetables, mushroom, bakery, fishery, sauces, cooked food, meat and particulate foods. The aim of this study was to apply the vacuum cooling and the conventional cooling techniques for the cooling of the meatball and to show the vacuum pressure effect on the cooling time, the temperature decrease and microbial growth rate. The results of the vacuum cooling and the conventional cooling (cooling in the refrigerator) were compared with each other for different temperatures. The study shows that the conventional cooling was much slower than the vacuum cooling. Moreover, the microbial growth rate of the vacuum cooling was extremely low compared with the conventional cooling. Thus, the lowest microbial growth occurred at 0.7 kPa and the highest microbial growth was observed at 1.5 kPa for the vacuum cooling. The mass loss ratio for the conventional cooling and vacuum cooling was about 5 and 9% respectively.
Recycling of waste lead storage battery by vacuum methods.
Lin, Deqiang; Qiu, Keqiang
2011-07-01
Waste lead storage battery is the most important recyclable lead material not only in various European and other OECD countries but also in China. Pollution control of lead has become the focus of people's attention in the world. A vacuum process for recycling waste lead storage battery was developed in this work. The experimental results showed that all the valuable materials in waste lead storage battery could be satisfactorily recycled by vacuum technologies. The vacuum melting of lead grids and the vacuum reduction of lead pastes produce the lead bullion with the direct recovery ratio of 96.29% and 98.98%, respectively. The vacuum pyrolysis of plastics can produce pyrolysis oil with yield of more than 93 wt.%. These vacuum recycling technologies offer improvements in metallurgical and environmental performance. Copyright © 2011 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Parsons-Wingerter, Patricia; Radhakrishnan, Krishnan; DiCorleto, Paul E.; Leontiev, Dmitry; Anand-Apte, Bela; Albarran, Brian; Farr, Andrew G.
2005-01-01
Vascular endothelial growth factor-165 (VEGF(sub 165)) stimulated angiogenesis in the quail chorioallantoic membrane (CAM) by vessel expansion from the capillary network. However, lymphangiogenesis was stimulated by the filopodial guidance of tip cells located on blind-ended lymphatic sprouts. As quantified by fractal/generational branching analysis using the computer code VESGEN, vascular density increased maximally at low VEGF concentrations, and vascular diameter increased most at high VEGF concentrations. Increased vascular density and diameter were statistically independent events (r(sub s), -0.06). By fluorescence immunohistochemistry of VEGF receptors VEGFR-1 and VEGFR-2, alpha smooth muscle actin ((alpha) SMA) and a vascular/lymphatic marker, VEGF(sub 165) increased the density and diameter of sprouting lymphatic vessels guided by tip cells (accompanied by the dissociation of lymphatics from blood vessels). Isolated migratory cells expressing (alpha)SMA were recruited to blood vessels, whereas isolated cells expressing VEGFR-2 were recruited primarily to lymphatics. In conclusion, VEGF(sub 165) increased lymphatic vessel density by lymphatic sprouting, but increased blood vessel density by vascular expansion from the capillary network.
Sealed vacuum canister and method for pick-up and containment of material
Stoutenburgh, R.R.
1996-02-13
A vacuum canister is described including a housing with a sealed vacuum chamber having a predetermined vacuum pressure therein and a valve having a first port for fluid communication with the vacuum chamber and a second port for receiving at least one of a fluid and a particulate material. The valve is operable between a first position to seal the vacuum chamber and retain the predetermined vacuum within the vacuum chamber, and a second position to access the vacuum chamber to permit vacuum fluid flow through the valve from the second port into the vacuum chamber. The vacuum canister, in the operation to pick up material with the valve in the second position, when the second port is located adjacent at least one of a fluid and a particulate material, is effective to displace through the valve at least one of a fluid and a particulate material into the housing. The vacuum canister is desirably suitable for picking up and containing hazardous material such as radioactive material, in which the vacuum canister includes a protective layer of lead having a predetermined thickness that is effective to shield radiation emitted from the radioactive material contained within the housing. Advantageously, the vacuum canister includes a vacuum means for establishing a predetermined vacuum pressure within the vacuum chamber. 6 figs.
46 CFR 169.119 - Vessel status.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 7 2010-10-01 2010-10-01 false Vessel status. 169.119 Section 169.119 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS General.... 883 a sailing school vessel is not deemed a merchant vessel or a vessel engaged in trade or commerce. ...
46 CFR 169.119 - Vessel status.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 7 2011-10-01 2011-10-01 false Vessel status. 169.119 Section 169.119 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS General.... 883 a sailing school vessel is not deemed a merchant vessel or a vessel engaged in trade or commerce. ...
Vacuum transfer system increases sugar maple sap yield
Russell S. Walters
1978-01-01
Yields of sugar maple sap collected from three plastic pipeline systems by gravity, vacuum pump, and a vacuum pump with a transfer tank were compared during 2 years in northern Vermont. The transfer system yielded 27 percent more sap one year and 17 percent more the next year. Higher vacuum levels at the tapholes were observed in the transfer system.
Vacuum plasma coatings for turbine blades
NASA Technical Reports Server (NTRS)
Holmes, R. R.
1985-01-01
Turbine blades, vacuum plasma spray coated with NiCrAlY, CoCrAlY or NiCrAlY/Cr2O3, were evaluated and rated superior to standard space shuttle main engine (SSME) coated blades. Ratings were based primarily on 25 thermal cycles in the MSFC Burner Rig Tester, cycling between 1700 F (gaseous H2) and -423 F (liquid H2). These tests showed no spalling on blades with improved vacuum plasma coatings, while standard blades spalled. Thermal barrier coatings of ZrO2, while superior to standard coatings, lacked the overall performance desired. Fatigue and tensile specimens, machined from MAR-M-246(Hf) test bars identical to the blades were vacuum plasma spray coated, diffusion bond treated, and tested to qualify the vacuum plasma spray process for flight hardware testing and application. While NiCrAlY/Cr2O3 offers significant improvement over standard coatings in durability and thermal protection, studies continue with an objective to develop coatings offering even greater improvements.
Vessel disposal general permits are issued by the EPA under the Marine Protection, Research and Sanctuaries Act. Information is provided for vessel disposal permit applicants and where to dispose a vessel.
Self contained, independent, in-vacuum spinner motor
Ayers, Marion J.
2002-01-01
An independent, self contained apparatus for operation within a vacuum chamber. A sealed enclosure is located in the chamber. The enclosure contains its own atmosphere independent of the vacuum in the chamber. A motor, power unit, and controls are located entirely within the enclosure. They do not have a direct structural connection outside of the enclosure in any way that would effect the atmosphere within the enclosure. The motor, power unit, and controls drive a spinner plate located outside the enclosure but within the vacuum chamber.
Microscale Digital Vacuum Electronic Gates
NASA Technical Reports Server (NTRS)
Manohara, Harish (Inventor); Mojarradi, Mohammed M. (Inventor)
2014-01-01
Systems and methods in accordance with embodiments of the invention implement microscale digital vacuum electronic gates. In one embodiment, a microscale digital vacuum electronic gate includes: a microscale field emitter that can emit electrons and that is a microscale cathode; and a microscale anode; where the microscale field emitter and the microscale anode are disposed within at least a partial vacuum; where the microscale field emitter and the microscale anode are separated by a gap; and where the potential difference between the microscale field emitter and the microscale anode is controllable such that the flow of electrons between the microscale field emitter and the microscale anode is thereby controllable; where when the microscale anode receives a flow of electrons, a first logic state is defined; and where when the microscale anode does not receive a flow of electrons, a second logic state is defined.
Instrument for measurement of vacuum in sealed thin wall packets
Kollie, T.G.; Thacker, L.H.; Fine, H.A.
1995-04-18
An instrument is disclosed for the measurement of vacuum within sealed packets, the packets having a wall that it can be deformed by the application of an external dynamic vacuum to an area thereof. The instrument has a detector head for placement against the deformable wall of the packet to apply the vacuum in a controlled manner to accomplish a limited deformation or lift of the wall with this deformation or lift monitored by the application of light as via a bifurcated light pipe. Retro-reflected light through the light pipe is monitored with a photo detector. A change (e.g., a decrease) of retro-reflected light signals the wall movement such that the value of the dynamic vacuum applied through the head be to achieve this initiation of movement is equal to the vacuum within the packet. In a preferred embodiment a vacuum plate is placed beneath the packet to ensure that no deformation occurs on the reverse surface of the packet. A vacuum can be applied to a recess in this vacuum plate, the value of which can be used to calibrate the vacuum transducer in the detector head. 4 figs.
Ferry Lifecycle Cost Model for Federal Land Management Agencies : User's Guide.
DOT National Transportation Integrated Search
2011-09-30
The Ferry Lifecycle Cost Model (model) is a spreadsheet-based sketch planning tool that estimates capital, operating, and total cost for various vessels that could be used to provide ferry service on a particular route given known service parameters....
Dyonic Flux Tube Structure of Nonperturbative QCD Vacuum
NASA Astrophysics Data System (ADS)
Chandola, H. C.; Pandey, H. C.
We study the flux tube structure of the nonperturbative QCD vacuum in terms of its dyonic excitations by using an infrared effective Lagrangian and show that the dyonic condensation of QCD vacuum has a close connection with the process of color confinement. Using the fiber bundle formulation of QCD, the magnetic symmetry condition is presented in a gauge covariant form and the gauge potential has been constructed in terms of the magnetic vectors on global sections. The dynamical breaking of the magnetic symmetry has been shown to lead the dyonic condensation of QCD vacuum in the infrared energy sector. Deriving the asymptotic solutions of the field equations in the dynamically broken phase, the dyonic flux tube structure of QCD vacuum is explored which has been shown to lead the confinement parameters in terms of the vector and scalar mass modes of the condensed vacuum. Evaluating the charge quantum numbers and energy associated with the dyonic flux tube solutions, the effect of electric excitation of monopole is analyzed using the Regge slope parameter (as an input parameter) and an enhancement in the dyonic pair correlations and the confining properties of QCD vacuum in its dyonically condensed mode has been demonstrated.
Flow Visualization Proposed for Vacuum Cleaner Nozzle Designs
NASA Technical Reports Server (NTRS)
2005-01-01
In 1995, the NASA Lewis Research Center and the Kirby Company (a major vacuum cleaner company) began negotiations for a Space Act Agreement to conduct research, technology development, and testing involving the flow behavior of airborne particulate flow behavior. Through these research efforts, we hope to identify ways to improve suction, flow rate, and surface agitation characteristics of nozzles used in vacuum cleaner nozzles. We plan to apply an advanced visualization technology, known as Stereoscopic Imaging Velocimetry (SIV), to a Kirby G-4 vacuum cleaner. Resultant data will be analyzed with a high-speed digital motion analysis system. We also plan to evaluate alternative vacuum cleaner nozzle designs. The overall goal of this project is to quantify both velocity fields and particle trajectories throughout the vacuum cleaner nozzle to optimize its "cleanability"--its ability to disturb and remove embedded dirt and other particulates from carpeting or hard surfaces. Reference
Containment vessel drain system
Harris, Scott G.
2018-01-30
A system for draining a containment vessel may include a drain inlet located in a lower portion of the containment vessel. The containment vessel may be at least partially filled with a liquid, and the drain inlet may be located below a surface of the liquid. The system may further comprise an inlet located in an upper portion of the containment vessel. The inlet may be configured to insert pressurized gas into the containment vessel to form a pressurized region above the surface of the liquid, and the pressurized region may operate to apply a surface pressure that forces the liquid into the drain inlet. Additionally, a fluid separation device may be operatively connected to the drain inlet. The fluid separation device may be configured to separate the liquid from the pressurized gas that enters the drain inlet after the surface of the liquid falls below the drain inlet.
Red rubber bulb, cheap and effective vacuum drainage.
Vatanasapt, V; Areemit, S; Jeeravipoolvarn, P; Kuyyakanond, T; Kuptarnond, C
1989-04-01
Red rubber bulbs have been used for vacuum drainage in head, neck, breast and several other operations by the authors since 1975 quite effectively without any major problems. The vacuum pressure of the red rubber bulbs was found to be higher than the expensive commercially available vacuum wound drainage device. The question of remaining old blood and infective microorganisms inside the reservoir for the reused ones were tested by the manual cleaning process and the standard sterile technique using steam under increased pressure (autoclave). The result is quite satisfactory. We encourage the use of this cheap and effective (made in Thailand) vacuum wound drainage in Thai hospitals and Thai medical schools.
Study of Vacuum Energy Physics for Breakthrough Propulsion
NASA Technical Reports Server (NTRS)
Millis, Marc G. (Technical Monitor); Maclay, G. Jordan; Hammer, Jay; Clark, Rod; George, Michael; Kim, Yeong; Kir, Asit
2004-01-01
This report summarizes the accomplishments during a three year research project to investigate the use of surfaces, particularly in microelectromechanical systems (MEMS), to exploit quantum vacuum forces. During this project, we developed AFM instrumentation to repeatably measure Casimir forces in the nanoNewton range at 10 6 torr, designed an experiment to measure attractive and repulsive quantum vacuum forces, developed a QED based theory of Casimir forces that includes non-ideal material properties for rectangular cavities and for multilayer slabs, developed theoretical models for a variety of microdevices utilizing vacuum forces, applied vacuum physics to a gedanken spacecraft, and investigated a new material with a negative index of refraction.
Code of Federal Regulations, 2012 CFR
2012-10-01
... oil spill response vessel certification. 126.225 Section 126.225 Shipping COAST GUARD, DEPARTMENT OF... Inspection § 126.225 Alternate tonnage for offshore supply vessels seeking oil spill response vessel... also be certificated as an oil spill response vessel. [76 FR 77131, Dec. 12, 2011] ...
Fast MRI-guided vacuum-assisted breast biopsy: initial experience.
Liberman, Laura; Morris, Elizabeth A; Dershaw, D David; Thornton, Cynthia M; Van Zee, Kimberly J; Tan, Lee K
2003-11-01
The purpose of this study was to evaluate a new method for performing MRI-guided vacuum-assisted breast biopsy in a study of lesions that had subsequent surgical excision. SUBJECTS AND METHODS. Twenty women scheduled for MRI-guided needle localization and surgical biopsy were prospectively entered in the study. MRI-guided biopsy was performed with a vacuum-assisted probe, followed by placement of a localizing clip, and then needle localization for surgical excision. Vacuum-assisted biopsy and surgical histology were correlated. Vacuum-assisted biopsy was successfully performed in 19 (95%) of the 20 women. The median size of 27 MRI-detected lesions that had biopsy was 1.0 cm (range, 0.4-6.4 cm). Cancer was present in eight (30%) of 27 lesions and in six (32%) of 19 women; among these eight cancers, five were infiltrating and three were ductal carcinoma in situ (DCIS). Among these 27 lesions, histology was benign at vacuum-assisted biopsy and at surgery in 19 (70%), cancer at vacuum-assisted biopsy in six (22%), atypical ductal hyperplasia at vacuum-assisted biopsy and DCIS at surgery in one (4%), and benign at vacuum-assisted biopsy with surgery showing microscopic DCIS that was occult at MRI in one (4%). The median time to perform vacuum-assisted biopsy of a single lesion was 35 min (mean, 35 min; range, 24-48 min). Placement of a localizing clip, attempted in 26 lesions, was successful in 25 (96%) of 26, and the clip was retrieved on specimen radiography in 22 (96%) of 23. One complication occurred: a hematoma that resolved with compression. MRI-guided vacuum-assisted biopsy is a fast, safe, and accurate alternative to surgical biopsy for breast lesions detected on MRI.
Tailoring vessel morphology in vivo
NASA Astrophysics Data System (ADS)
Gould, Daniel Joseph
Tissue engineering is a rapidly growing field which seeks to provide alternatives to organ transplantation in order to address the increasing need for transplantable tissues. One huge hurdle in this effort is the provision of thick tissues; this hurdle exists because currently there is no way to provide prevascularized or rapidly vascularizable scaffolds. To design thick, vascularized tissues, scaffolds are needed that can induce vessels which are similar to the microvasculature found in normal tissues. Angiogenic biomaterials are being developed to provide useful scaffolds to address this problem. In this thesis angiogenic and cell signaling and adhesion factors were incorporated into a biomimetic poly(ethylene glycol) (PEG) hydrogel system. The composition of these hydrogels was precisely tuned to induce the formation of differing vessel morphology. To sensitively measure induced microvascular morphology and to compare it to native microvessels in several tissues, this thesis developed an image-based tool for quantification of scale invariant and classical measures of vessel morphology. The tool displayed great utility in the comparison of native vessels and remodeling vessels in normal tissues. To utilize this tool to tune the vessel response in vivo, Flk1::myr-mCherry fluorescently labeled mice were implanted with Platelet Derived Growth Factor-BB (PDGF-BB) and basic Fibroblast Growth Factor (FGF-2) containing PEG-based hydrogels in a modified mouse corneal angiogenesis assay. Resulting vessels were imaged with confocal microscopy, analyzed with the image based tool created in this thesis to compare morphological differences between treatment groups, and used to create a linear relationship between space filling parameters and dose of growth factor release. Morphological parameters of native mouse tissue vessels were then compared to the linear fit to calculate the dose of growth factors needed to induce vessels similar in morphology to native vessels
19 CFR 4.5 - Government vessels.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 19 Customs Duties 1 2010-04-01 2010-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...
19 CFR 4.5 - Government vessels.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 19 Customs Duties 1 2013-04-01 2013-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...
19 CFR 4.5 - Government vessels.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 19 Customs Duties 1 2011-04-01 2011-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...
19 CFR 4.5 - Government vessels.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 19 Customs Duties 1 2014-04-01 2014-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...
19 CFR 4.5 - Government vessels.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 19 Customs Duties 1 2012-04-01 2012-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...
Rudyanto, Rina D.; Kerkstra, Sjoerd; van Rikxoort, Eva M.; Fetita, Catalin; Brillet, Pierre-Yves; Lefevre, Christophe; Xue, Wenzhe; Zhu, Xiangjun; Liang, Jianming; Öksüz, İlkay; Ünay, Devrim; Kadipaşaogandcaron;lu, Kamuran; Estépar, Raúl San José; Ross, James C.; Washko, George R.; Prieto, Juan-Carlos; Hoyos, Marcela Hernández; Orkisz, Maciej; Meine, Hans; Hüllebrand, Markus; Stöcker, Christina; Mir, Fernando Lopez; Naranjo, Valery; Villanueva, Eliseo; Staring, Marius; Xiao, Changyan; Stoel, Berend C.; Fabijanska, Anna; Smistad, Erik; Elster, Anne C.; Lindseth, Frank; Foruzan, Amir Hossein; Kiros, Ryan; Popuri, Karteek; Cobzas, Dana; Jimenez-Carretero, Daniel; Santos, Andres; Ledesma-Carbayo, Maria J.; Helmberger, Michael; Urschler, Martin; Pienn, Michael; Bosboom, Dennis G.H.; Campo, Arantza; Prokop, Mathias; de Jong, Pim A.; Ortiz-de-Solorzano, Carlos; Muñoz-Barrutia, Arrate; van Ginneken, Bram
2016-01-01
The VESSEL12 (VESsel SEgmentation in the Lung) challenge objectively compares the performance of different algorithms to identify vessels in thoracic computed tomography (CT) scans. Vessel segmentation is fundamental in computer aided processing of data generated by 3D imaging modalities. As manual vessel segmentation is prohibitively time consuming, any real world application requires some form of automation. Several approaches exist for automated vessel segmentation, but judging their relative merits is difficult due to a lack of standardized evaluation. We present an annotated reference dataset containing 20 CT scans and propose nine categories to perform a comprehensive evaluation of vessel segmentation algorithms from both academia and industry. Twenty algorithms participated in the VESSEL12 challenge, held at International Symposium on Biomedical Imaging (ISBI) 2012. All results have been published at the VESSEL12 website http://vessel12.grand-challenge.org. The challenge remains ongoing and open to new participants. Our three contributions are: (1) an annotated reference dataset available online for evaluation of new algorithms; (2) a quantitative scoring system for objective comparison of algorithms; and (3) performance analysis of the strengths and weaknesses of the various vessel segmentation methods in the presence of various lung diseases. PMID:25113321
NASA Astrophysics Data System (ADS)
Chaturvedi, Amal; Shukair, Shetha A.; Le Rolland, Paul; Vijayvergia, Mayank; Subramanian, Hariharan; Gunn, Jonathan W.
2016-03-01
Minimally invasive operations require surgeons to make difficult cuts to blood vessels and other tissues with impaired tactile and visual feedback. This leads to inadvertent cuts to blood vessels hidden beneath tissue, causing serious health risks to patients and a non-reimbursable financial burden to hospitals. Intraoperative imaging technologies have been developed, but these expensive systems can be cumbersome and provide only a high-level view of blood vessel networks. In this research, we propose a lean reflectance-based system, comprised of a dual wavelength LED, photodiode, and novel signal processing algorithms for rapid vessel characterization. Since this system takes advantage of the inherent pulsatile light absorption characteristics of blood vessels, no contrast agent is required for its ability to detect the presence of a blood vessel buried deep inside any tissue type (up to a cm) in real time. Once a vessel is detected, the system is able to estimate the distance of the vessel from the probe and the diameter size of the vessel (with a resolution of ~2mm), as well as delineate the type of tissue surrounding the vessel. The system is low-cost, functions in real-time, and could be mounted on already existing surgical tools, such as Kittner dissectors or laparoscopic suction irrigation cannulae. Having been successfully validated ex vivo, this technology will next be tested in a live porcine study and eventually in clinical trials.
Feed-through connector couples RF power into vacuum chamber
NASA Technical Reports Server (NTRS)
Grandy, G. L.
1967-01-01
Feed-through device connects RF power to an RF coil in a vacuum chamber. The coil and leads are water cooled and vacuum tight seals are provided at the junctions. The device incorporates silver soldered copper tubes, polytetrafluoroethylene electrical insulators, and O-ring vacuum seals.
Tokamak DEMO-FNS: Concept of magnet system and vacuum chamber
DOE Office of Scientific and Technical Information (OSTI.GOV)
Azizov, E. A., E-mail: Azizov-EA@nrcki.ru; Ananyev, S. S.; Belyakov, V. A.
The level of knowledge accumulated to date in the physics and technologies of controlled thermonuclear fusion (CTF) makes it possible to begin designing fusion—fission hybrid systems that would involve a fusion neutron source (FNS) and which would admit employment for the production of fissile materials and for the transmutation of spent nuclear fuel. Modern Russian strategies for CTF development plan the construction to 2023 of tokamak-based demonstration hybrid FNS for implementing steady-state plasma burning, testing hybrid blankets, and evolving nuclear technologies. Work on designing the DEMO-FNS facility is still in its infancy. The Efremov Institute began designing its magnet systemmore » and vacuum chamber, while the Kurchatov Institute developed plasma-physics design aspects and determined basic parameters of the facility. The major radius of the plasma in the DEMO-FNS facility is R = 2.75 m, while its minor radius is a = 1 m; the plasma elongation is k{sub 95} = 2. The fusion power is P{sub FUS} = 40 MW. The toroidal magnetic field on the plasma-filament axis is B{sub t0} = 5 T. The plasma current is I{sub p} = 5 MA. The application of superconductors in the magnet system permits drastically reducing the power consumed by its magnets but requires arranging a thick radiation shield between the plasma and magnet system. The central solenoid, toroidal-field coils, and poloidal-field coils are manufactured from, respectively, Nb{sub 3}Sn, NbTi and Nb{sub 3}Sn, and NbTi. The vacuum chamber is a double-wall vessel. The space between the walls manufactured from 316L austenitic steel is filled with an iron—water radiation shield (70% of stainless steel and 30% of water).« less
Heat transfer in a liquid helium cooled vacuum tube following sudden vacuum loss
NASA Astrophysics Data System (ADS)
Dhuley, R. C.; Van Sciver, S. W.
2015-12-01
Condensation of nitrogen gas rapidly flowing into a liquid helium (LHe) cooled vacuum tube is studied. This study aims to examine the heat transfer in geometries such as the superconducting RF cavity string of a particle accelerator following a sudden loss of vacuum to atmosphere. In a simplified experiment, the flow is generated by quickly venting a large reservoir of nitrogen gas to a straight long vacuum tube immersed in LHe. Normal LHe (LHe I) and superfluid He II are used in separate experiments. The rate of condensation heat transfer is determined from the temperature of the tube measured at several locations along the gas flow. Instantaneous heat deposition rates in excess of 200 kW/m2 result from condensation of the flowing gas. The gas flow is then arrested in its path to pressurize the tube to atmosphere and estimate the heat transfer rate to LHe. A steady LHe I heat load of ≈25 kW/m2 is obtained in this scenario. Observations from the He II experiment are briefly discussed. An upper bound for the LHe I heat load is derived based on the thermodynamics of phase change of nitrogen.
Intravascular perfusion of carbon black ink allows reliable visualization of cerebral vessels.
Hasan, Mohammad R; Herz, Josephine; Hermann, Dirk M; Doeppner, Thorsten R
2013-01-04
The anatomical structure of cerebral vessels is a key determinant for brain hemodynamics as well as the severity of injury following ischemic insults. The cerebral vasculature dynamically responds to various pathophysiological states and it exhibits considerable differences between strains and under conditions of genetic manipulations. Essentially, a reliable technique for intracranial vessel staining is essential in order to study the pathogenesis of ischemic stroke. Until recently, a set of different techniques has been employed to visualize the cerebral vasculature including injection of low viscosity resin, araldite F, gelatin mixed with various dyes (i.e. carmine red, India ink) or latex with or without carbon black. Perfusion of white latex compound through the ascending aorta has been first reported by Coyle and Jokelainen. Maeda et al. have modified the protocol by adding carbon black ink to the latex compound for improved contrast visualization of the vessels after saline perfusion of the brain. However, inefficient perfusion and inadequate filling of the vessels are frequently experienced due to high viscosity of the latex compound. Therefore, we have described a simple and cost-effective technique using a mixture of two commercially available carbon black inks (CB1 and CB2) to visualize the cerebral vasculature in a reproducible manner. We have shown that perfusion with CB1+CB2 in mice results in staining of significantly smaller cerebral vessels at a higher density in comparison to latex perfusion. Here, we describe our protocol to identify the anastomotic points between the anterior (ACA) and middle cerebral arteries (MCA) to study vessel variations in mice with different genetic backgrounds. Finally, we demonstrate the feasibility of our technique in a transient focal cerebral ischemia model in mice by combining CB1+CB2-mediated vessel staining with TTC staining in various degrees of ischemic injuries.
Instrument for measurement of vacuum in sealed thin wall packets
Kollie, Thomas G.; Thacker, Louis H.; Fine, H. Alan
1995-01-01
An instrument for the measurement of vacuum within sealed packets 12, the packets 12 having a wall 14 that it can be deformed by the application of an external dynamic vacuum to an area thereof. The instrument has a detector head 18 for placement against the deformable wall 14 of the packet to apply the vacuum in a controlled manner to accomplish a limited deformation or lift of the wall 14, with this deformation or lift monitored by the application of light as via a bifurcated light pipe 20. Retro-reflected light through the light pipe is monitored with a photo detector 26. A change (e.g., a decrease) of retro-reflected light signals the wall movement such that the value of the dynamic vacuum applied through the head be to achieve this initiation of movement is equal to the vacuum within the packet 12. In a preferred embodiment a vacuum plate 44 is placed beneath the packet 12 to ensure that no deformation occurs on the reverse surface 16 of the packet. A vacuum can be applied to a recess in this vacuum plate, the value of which can be used to calibrate the vacuum transducer in the detector head.
7 CFR 58.217 - Evaporators and/or vacuum pans.
Code of Federal Regulations, 2011 CFR
2011-01-01
....217 Evaporators and/or vacuum pans. Evaporators or vacuum pans or both, with open type condensers shall be equipped with an automatic condenser water level control, barometric leg, or so constructed so... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. When enclosed type condensers...
Quantum vacuum effects from boundaries of designer potentials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Konopka, Tomasz
2009-04-15
Vacuum energy in quantum field theory, being the sum of zero-point energies of all field modes, is formally infinite but yet, after regularization or renormalization, can give rise to finite observable effects. One way of understanding how these effects arise is to compute the vacuum energy in an idealized system such as a large cavity divided into disjoint regions by pistons. In this paper, this type of calculation is carried out for situations where the potential affecting a field is not the same in all regions of the cavity. It is shown that the observable parts of the vacuum energymore » in such potentials do not fall off to zero as the region where the potential is nontrivial becomes large. This unusual behavior might be interesting for tests involving quantum vacuum effects and for studies on the relation between vacuum energy in quantum field theory and geometry.« less
A squeezed light source operated under high vacuum
Wade, Andrew R.; Mansell, Georgia L.; Chua, Sheon S. Y.; Ward, Robert L.; Slagmolen, Bram J. J.; Shaddock, Daniel A.; McClelland, David E.
2015-01-01
Non-classical squeezed states of light are becoming increasingly important to a range of metrology and other quantum optics applications in cryptography, quantum computation and biophysics. Applications such as improving the sensitivity of advanced gravitational wave detectors and the development of space-based metrology and quantum networks will require robust deployable vacuum-compatible sources. To date non-linear photonics devices operated under high vacuum have been simple single pass systems, testing harmonic generation and the production of classically correlated photon pairs for space-based applications. Here we demonstrate the production under high-vacuum conditions of non-classical squeezed light with an observed 8.6 dB of quantum noise reduction down to 10 Hz. Demonstration of a resonant non-linear optical device, for the generation of squeezed light under vacuum, paves the way to fully exploit the advantages of in-vacuum operations, adapting this technology for deployment into new extreme environments. PMID:26657616
A squeezed light source operated under high vacuum
NASA Astrophysics Data System (ADS)
Wade, Andrew R.; Mansell, Georgia L.; Chua, Sheon S. Y.; Ward, Robert L.; Slagmolen, Bram J. J.; Shaddock, Daniel A.; McClelland, David E.
2015-12-01
Non-classical squeezed states of light are becoming increasingly important to a range of metrology and other quantum optics applications in cryptography, quantum computation and biophysics. Applications such as improving the sensitivity of advanced gravitational wave detectors and the development of space-based metrology and quantum networks will require robust deployable vacuum-compatible sources. To date non-linear photonics devices operated under high vacuum have been simple single pass systems, testing harmonic generation and the production of classically correlated photon pairs for space-based applications. Here we demonstrate the production under high-vacuum conditions of non-classical squeezed light with an observed 8.6 dB of quantum noise reduction down to 10 Hz. Demonstration of a resonant non-linear optical device, for the generation of squeezed light under vacuum, paves the way to fully exploit the advantages of in-vacuum operations, adapting this technology for deployment into new extreme environments.
Ultrahigh vacuum and low-temperature cleaning of oxide surfaces using a low-concentration ozone beam
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pratt, A.; Department of Physics, University of York, Heslington, York YO10 5DD; Graziosi, P.
We present a novel method of delivering a low-concentration (<15%) ozone beam to an ultra-high vacuum environment for the purpose of cleaning and dosing experimental samples through oxidation processing. The system described is safe, low-cost, and practical and overcomes the limitations of ozone transport in the molecular flow environment of high or ultrahigh vacuum whilst circumventing the use of pure ozone gas which is potentially highly explosive. The effectiveness of this method in removing surface contamination is demonstrated through comparison of high-temperature annealing of a simple oxide (MgO) in ozone and oxygen environments as monitored using quadrupole mass spectroscopy andmore » Auger electron spectroscopy. Additionally, we demonstrate the potential of ozone for obtaining clean complex oxide surfaces without the need for high-temperature annealing which may significantly alter surface structure.« less
Vacuum Outgassing of High Density Polyethylene
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dinh, L N; Sze, J; Schildbach, M A
A combination of thermogravimetric analysis (TGA) and temperature programmed decomposition (TPD) was employed to identify the outgassing species, the total amount of outgassing, and the outgassing kinetics of high density polyethylene (HDPE) in a vacuum environment. The isoconversional kinetic analysis was then used to analyze the outgassing kinetics and to predict the long-term outgassing of HDPE in vacuum applications at ambient temperature. H{sub 2}O and C{sub n}H{sub x} with n as high as 9 and x centering around 2n are the major outgassing species from solid HDPE, but the quantities evolved can be significantly reduced by vacuum baking at 368more » K for a few hours prior to device assembly.« less
Code of Federal Regulations, 2013 CFR
2013-10-01
... oil spill response vessel certification. 126.225 Section 126.225 Shipping COAST GUARD, DEPARTMENT OF... Inspection § 126.225 Alternate tonnage for offshore supply vessels seeking oil spill response vessel... also be certificated as an oil spill response vessel. [82-004 and CGD 86-074, 62 FR 49324, Sept. 19...
Code of Federal Regulations, 2014 CFR
2014-10-01
... oil spill response vessel certification. 126.225 Section 126.225 Shipping COAST GUARD, DEPARTMENT OF... Inspection § 126.225 Alternate tonnage for offshore supply vessels seeking oil spill response vessel... also be certificated as an oil spill response vessel. [82-004 and CGD 86-074, 62 FR 49324, Sept. 19...
NASA Astrophysics Data System (ADS)
Zhang, F.; Chen, Y.; Tian, C.; Li, J.; Zhang, G.; Matthias, V.
2015-09-01
Shipping emissions have significant influence on atmospheric environment as well as human health, especially in coastal areas and the harbor districts. However, the contribution of shipping emissions on the environment in China still need to be clarified especially based on measurement data, with the large number ownership of vessels and the rapid developments of ports, international trade and shipbuilding industry. Pollutants in the gaseous phase (carbon monoxide, sulfur dioxide, nitrogen oxides, total volatile organic compounds) and particle phase (particulate matter, organic carbon, elemental carbon, sulfates, nitrate, ammonia, metals) in the exhaust from three different diesel engine power offshore vessels in China were measured in this study. Concentrations, fuel-based and power-based emissions factors for various operating modes as well as the impact of engine speed on emissions were determined. Observed concentrations and emissions factors for carbon monoxide, nitrogen oxides, total volatile organic compounds, and particulate matter were higher for the low engine power vessel than for the two higher engine power vessels. Fuel-based average emissions factors for all pollutants except sulfur dioxide in the low engine power engineering vessel were significantly higher than that of the previous studies, while for the two higher engine power vessels, the fuel-based average emissions factors for all pollutants were comparable to the results of the previous studies. The fuel-based average emissions factor for nitrogen oxides for the small engine power vessel was more than twice the International Maritime Organization standard, while those for the other two vessels were below the standard. Emissions factors for all three vessels were significantly different during different operating modes. Organic carbon and elemental carbon were the main components of particulate matter, while water-soluble ions and elements were present in trace amounts. Best-fit engine speeds
Cuff for Blood-Vessel Pressure Measurements
NASA Technical Reports Server (NTRS)
Shimizu, M.
1982-01-01
Pressure within blood vessel is measured by new cufflike device without penetration of vessel. Device continuously monitors blood pressure for up to 6 months or longer without harming vessel. Is especially useful for vessels smaller than 4 or 5 millimeters in diameter. Invasive methods damage vessel wall, disturb blood flow, and cause clotting. They do not always give reliable pressure measurements over prolonged periods.
Vacuum birefringence detection in all-optical scenarios
NASA Astrophysics Data System (ADS)
Ataman, Stefan
2018-06-01
In this paper we propose an all-optical vacuum birefringence experiment and evaluate its feasibility for various scenarios. Many petawatt-class lasers became operational and many more are expected to enter operation in the near future, therefore unprecedented electromagnetic fields (EL˜1014-1015 V/m and intensities IL˜1021-1023W/cm 2 ) will become available for experiments. In our proposal a petawatt-class laser disturbs the quantum vacuum and creates a delay in a counterpropagating probe laser beam. Placing this delayed beam in one arm of a Mach-Zehnder interferometer (MZI), allows the measurement of the vacuum refraction coefficient via a phase shift. Coherent as well as squeezed light are both considered and the minimum phase sensitivity evaluated. We show that using existing technology with some moderately optimistic assumptions, at least part of the discussed scenarios are feasible for a vacuum birefringence detection experiment.
Relaxation of vacuum energy in q-theory
NASA Astrophysics Data System (ADS)
Klinkhamer, F. R.; Savelainen, M.; Volovik, G. E.
2017-08-01
The q-theory formalism aims to describe the thermodynamics and dynamics of the deep quantum vacuum. The thermodynamics leads to an exact cancellation of the quantum-field zero-point-energies in equilibrium, which partly solves the main cosmological constant problem. But, with reversible dynamics, the spatially flat Friedmann-Robertson-Walker universe asymptotically approaches the Minkowski vacuum only if the Big Bang already started out in an initial equilibrium state. Here, we extend q-theory by introducing dissipation from irreversible processes. Neglecting the possible instability of a de-Sitter vacuum, we obtain different scenarios with either a de-Sitter asymptote or collapse to a final singularity. The Minkowski asymptote still requires fine-tuning of the initial conditions. This suggests that, within the q-theory approach, the decay of the de-Sitter vacuum is a necessary condition for the dynamical solution of the cosmological constant problem.
Optimization of Helium Vessel Design for ILC Cavities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fratangelo, Enrico
2009-01-01
certify the compliance of the Helium vessel and the cavity to the ASME code standard. After briefly recalling to the main contents of the the ASME Code (Sections II and Vlll - Division ll), the procedure used for finding all relevant stresses and comparing the obtained results with the maximum values allowed are explained. This part also includes the buckling verification of the cavity. In Chapter 5 the manufacturing process of the cavity end-caps, whose function is to link the Helium vessel with the cavity, is studied. The present configuration of the dies is described and the manufacturing process is simulated in order to explain the origin of some defects fol.llld on real parts. Finally a new design of the dies is proposed and the resulting deformed piece is compared with the design requirements. Chapter 6 describes a finite elements analysis to assess the efficiency and the stiffness of the Helium vessel. Furthermore the results of the optimization of the Helium vessel (in order to increase the value of the efficiency) are reported. The same stiffness analysis is used in Chapter 7 for the Blade-Tuner study. After a description of this tuner and of its function, the preliminary analyses done to confirm the results provided by the vendor are described and then its limiting load conditions are found. Chapter 8 shows a study of the resistance of all the welds present in between the cavity and the end-cap and between the end-caps and the He vessel for a smaller superconducting cavity operating at 3.9 GHz. Finally Chapter 9 briefly describes some R&D activities in progress at INFN (Section of Pisa) and Fermilab that could produce significant cost reductions of the Helium vessel design. All the finite elements analyses contained and described in this thesis made possible the certification of the whole superconducting cavity-Helium vessel assembly at Fermilab. Furthermore they gave several useful indications to the Fermilab staff to improve the performance of the Helium
Vacuum Strength of Two Candidate Glasses for a Space Observatory
NASA Technical Reports Server (NTRS)
Manning, Timothy Andrew; Tucker, Dennis S.; Herren, Kenneth A.; Gregory, Don A.
2007-01-01
The strengths of two candidate glass types for use in a space observatory were measured. Samples of ultra-low expansion glass (ULE) and borosilicate (Pyrex) were tested in air and in vacuum at room temperature (20 degrees C) and in vacuum after being heated to 200 degrees C. Both glasses tested in vacuum showed a significant increase in strength over those tested in air. However, there was no statistical difference between the strength of samples tested in vacuum at room temperature and those tested in vacuum after heating to 200 degrees C.
Vacuum Strength of Two Candidate Glasses for a Space Observatory
NASA Technical Reports Server (NTRS)
Manning, T. a.; Tucker, D. S.; Herren, K. A.; Gregory, D. A.
2007-01-01
The strengths of two candidate glass types for use in a space observatory were measured. Samples of ultra-low expansion glass (ULE) and borosilicate (Pyrex) were tested in air and in vacuum at room temperature (20 C) and in vacuum after being heated to 200 C. Both glasses tested in vacuum showed an increase in strength over those tested in air. However, there was no statistical difference between the strength of samples tested in vacuum at room temperature and those tested in vacuum after heating to 200 C.
Expanding space-time and variable vacuum energy
NASA Astrophysics Data System (ADS)
Parmeggiani, Claudio
2017-08-01
The paper describes a cosmological model which contemplates the presence of a vacuum energy varying, very slightly (now), with time. The constant part of the vacuum energy generated, some 6 Gyr ago, a deceleration/acceleration transition of the metric expansion; so now, in an aged Universe, the expansion is inexorably accelerating. The vacuum energy varying part is instead assumed to be eventually responsible of an acceleration/deceleration transition, which occurred about 14 Gyr ago; this transition has a dynamic origin: it is a consequence of the general relativistic Einstein-Friedmann equations. Moreover, the vacuum energy (constant and variable) is here related to the zero-point energy of some quantum fields (scalar, vector, or spinor); these fields are necessarily described in a general relativistic way: their structure depends on the space-time metric, typically non-flat. More precisely, the commutators of the (quantum field) creation/annihilation operators are here assumed to depend on the local value of the space-time metric tensor (and eventually of its curvature); furthermore, these commutators rapidly decrease for high momentum values and they reduce to the standard ones for a flat metric. In this way, the theory is ”gravitationally” regularized; in particular, the zero-point (vacuum) energy density has a well defined value and, for a non static metric, depends on the (cosmic) time. Note that this varying vacuum energy can be negative (Fermi fields) and that a change of its sign typically leads to a minimum for the metric expansion factor (a ”bounce”).
Vacuum system of the cyclotrons in VECC, Kolkata
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roy, Anindya; Bhole, R.B.; Akhtar, J.
2011-07-01
The vacuum system of the K=130 Room Temperature Cyclotron (RTC) (operational since 1978) has been recently modernized and the same of the K{sub bend}=520 Superconducting Cyclotron (SCC), currently under commissioning, is being deployed for remote monitoring and control. The vacuum system of RTC is designed to achieve and maintain vacuum level of 2 X 10{sup -6} mbar inside 23 m{sup 3} volume of Resonator tank and DEE tank. This has been upgraded by replacing several valves, Freon units, gauges and pumps. The relay based manual control system has been replaced by PLC based automated system. The SCC vacuum system alsomore » has an elaborate arrangement comprising of turbo molecular pumping modules with associated isolation valves and characteristic gauges. This paper describes essential elements, typically used to obtain high (1X10{sup -7} mbar) vacuum using rotary pumps, diffusion pumps and cold traps/turbo-molecular pumps and other system components such as valves, gauges and baffles. The supervisory control methodology/scheme of both the vacuum systems, developed in-house using EPICS (Experimental Physics and Industrial Control System), a standard open-source software tool for designing distributed control system, is also elaborated here. (author)« less
Phacoemulsification tip vacuum pressure: Comparison of 4 devices.
Payne, Marielle; Georgescu, Dan; Waite, Aaron N; Olson, Randall J
2006-08-01
To determine the vacuum pressure generated by 4 phacoemulsification devices measured at the phacoemulsification tip. University ophthalmology department. The effective vacuum pressures generated by the Sovereign (AMO), Millennium (Bausch & Lomb), Legacy AdvanTec (Alcon Laboratories), and Infiniti (Alcon Laboratories) phacoemulsification machines were measured with a device that isolated the phacoemulsification tip in a chamber connected to a pressure gauge. The 4 machines were tested at multiple vacuum limit settings, and the values were recorded after the foot pedal was fully depressed and the pressure had stabilized. The AdvanTec and Infiniti machines were tested with and without occlusion of the Aspiration Bypass System (ABS) side port (Alcon Laboratories). The Millennium machine was tested using venturi and peristaltic pumps. The machines generated pressures close to the expected at maximum vacuum settings between 100 mm Hg and 500 mm Hg with few intermachine variations. There was no significant difference between pressures generated using 19- or 20-gauge tips (Millennium and Sovereign). The addition of an ABS side port decreased vacuum by a mean of 12.1% (P < .0001). Although there were some variations in vacuum pressures among phacoemulsification machines, particularly when an aspiration bypass tip was used, these discrepancies are probably not clinically significant.
Vacuum fusion bonding of glass plates
Swierkowski, Steve P.; Davidson, James C.; Balch, Joseph W.
2001-01-01
An improved apparatus and method for vacuum fusion bonding of large, patterned glass plates. One or both glass plates are patterned with etched features such as microstructure capillaries and a vacuum pumpout moat, with one plate having at least one hole therethrough for communication with a vacuum pumpout fixture. High accuracy alignment of the plates is accomplished by a temporary clamping fixture until the start of the fusion bonding heat cycle. A complete, void-free fusion bond of seamless, full-strength quality is obtained through the plates; because the glass is heated well into its softening point and because of a large, distributed force that is developed that presses the two plates together from the difference in pressure between the furnace ambient (high pressure) and the channeling and microstructures in the plates (low pressure) due to the vacuum drawn. The apparatus and method may be used to fabricate microcapillary arrays for chemical electrophoresis; for example, any apparatus using a network of microfluidic channels embedded between plates of glass or similar moderate melting point substrates with a gradual softening point curve, or for assembly of glass-based substrates onto larger substrates, such as in flat panel display systems.
Vacuum fusion bonding of glass plates
Swierkowski, Steve P.; Davidson, James C.; Balch, Joseph W.
2000-01-01
An improved apparatus and method for vacuum fusion bonding of large, patterned glass plates. One or both glass plates are patterned with etched features such as microstructure capillaries and a vacuum pumpout moat, with one plate having at least one hole therethrough for communication with a vacuum pumpout fixture. High accuracy alignment of the plates is accomplished by a temporary clamping fixture until the start of the fusion bonding heat cycle. A complete, void-free fusion bond of seamless, full-strength quality is obtained through the plates; because the glass is heated well into its softening point and because of a large, distributed force that is developed that presses the two plates together from the difference in pressure between the furnace ambient (high pressure) and the channeling and microstructures in the plates (low pressure) due to the vacuum drawn. The apparatus and method may be used to fabricate microcapillary arrays for chemical electrophoresis; for example, any apparatus using a network of microfluidic channels embedded between plates of glass or similar moderate melting point substrates with a gradual softening point curve, or for assembly of glass-based substrates onto larger substrates, such as in flat panel display systems.
Cost Differences in Public and Private Shipyards
1981-01-01
block number) coefficients, costs, maintenance, naval shore facilities, naval vessels, nuclear powered ships, regression analysis, repair, salaries...of overhauls of nucler submarines, we mnight exp.,_t to find both production costs and the price of labor to be higher in naval shipyardi than in...about 18 months; in addition to the type of work done during regular overhauls, they include replacement of the nuclear core which powers the submarine
Recent advances in vacuum sciences and applications
NASA Astrophysics Data System (ADS)
Mozetič, M.; Ostrikov, K.; Ruzic, D. N.; Curreli, D.; Cvelbar, U.; Vesel, A.; Primc, G.; Leisch, M.; Jousten, K.; Malyshev, O. B.; Hendricks, J. H.; Kövér, L.; Tagliaferro, A.; Conde, O.; Silvestre, A. J.; Giapintzakis, J.; Buljan, M.; Radić, N.; Dražić, G.; Bernstorff, S.; Biederman, H.; Kylián, O.; Hanuš, J.; Miloševič, S.; Galtayries, A.; Dietrich, P.; Unger, W.; Lehocky, M.; Sedlarik, V.; Stana-Kleinschek, K.; Drmota-Petrič, A.; Pireaux, J. J.; Rogers, J. W.; Anderle, M.
2014-04-01
Recent advances in vacuum sciences and applications are reviewed. Novel optical interferometer cavity devices enable pressure measurements with ppm accuracy. The innovative dynamic vacuum standard allows for pressure measurements with temporal resolution of 2 ms. Vacuum issues in the construction of huge ultra-high vacuum devices worldwide are reviewed. Recent advances in surface science and thin films include new phenomena observed in electron transport near solid surfaces as well as novel results on the properties of carbon nanomaterials. Precise techniques for surface and thin-film characterization have been applied in the conservation technology of cultural heritage objects and recent advances in the characterization of biointerfaces are presented. The combination of various vacuum and atmospheric-pressure techniques enables an insight into the complex phenomena of protein and other biomolecule conformations on solid surfaces. Studying these phenomena at solid-liquid interfaces is regarded as the main issue in the development of alternative techniques for drug delivery, tissue engineering and thus the development of innovative techniques for curing cancer and cardiovascular diseases. A review on recent advances in plasma medicine is presented as well as novel hypotheses on cell apoptosis upon treatment with gaseous plasma. Finally, recent advances in plasma nanoscience are illustrated with several examples and a roadmap for future activities is presented.
Compact vacuum insulation embodiments
Benson, David K.; Potter, Thomas F.
1992-01-01
An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially "point" or "line" contacts with the metal wall sheets. In the case of monolithic spacers that form "line" contacts, two such spacers with the line contacts running perpendicular to each other form effectively "point" contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.
46 CFR 169.249 - Pressure vessels.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 46 Shipping 7 2011-10-01 2011-10-01 false Pressure vessels. 169.249 Section 169.249 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Inspection and Certification Inspections § 169.249 Pressure vessels. Pressure vessels must meet the requirements...
46 CFR 169.249 - Pressure vessels.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 7 2010-10-01 2010-10-01 false Pressure vessels. 169.249 Section 169.249 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Inspection and Certification Inspections § 169.249 Pressure vessels. Pressure vessels must meet the requirements...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-13
... Compliance for the Offshore Supply Vessel/Well Stimulation Vessel BLUE TARPON AGENCY: Coast Guard, DHS... issued for the offshore supply vessel BLUE TARPON as required by 33 U.S.C. 1605(c) and 33 CFR 81.18... Regulation, Parts 81 and 89, has been issued for the offshore supply vessel BLUE TARPON, O.N. 1226288. The...
Vacuum decay in an interacting multiverse
NASA Astrophysics Data System (ADS)
Robles-Pérez, S.; Alonso-Serrano, A.; Bastos, C.; Bertolami, O.
2016-08-01
We examine a new multiverse scenario in which the component universes interact. We focus our attention to the process of "true" vacuum nucleation in the false vacuum within one single element of the multiverse. It is shown that the interactions lead to a collective behavior that might lead, under specific conditions, to a pre-inflationary phase and ensued distinguishable imprints in the comic microwave background radiation.
Vacuum extraction failure is associated with a large head circumference.
Kabiri, Doron; Lipschuetz, Michal; Cohen, Sarah M; Yagel, Oren; Levitt, Lorinne; Herzberg, Shmuel; Ezra, Yossef; Yagel, Simcha; Amsalem, Hagai
2018-04-24
To determine whether large head circumference increases the risk of vacuum extraction failure. This EMR-based study included all attempted vacuum extractions performed in a tertiary center between January 2010 and June 2015. All term singleton live births were eligible. Cases were divided into four groups: head circumference ≥90th percentile both with birth weight ≥90th percentile and <90th percentile and fetal head circumference <90th percentile with birth weight ≥90th and <90th percentile. Risk of failed vacuum extraction was compared among these groups. Other neonatal and maternal parameters were also evaluated as potential risk factors. Multinomial multivariable regression provided adjusted odds ratio for vacuum extraction failure while controlling for potential confounders. During the study period, 48,007 deliveries met inclusion criteria, of which 3835 had an attempt at vacuum extraction. We identified 215 (5.6%) cases of vacuum extraction failure. The adjusted odds ratios (aOR) for vacuum extraction failure in cases of large fetal head circumference was 2.31 (95%CI, 1.7-3.15, p < .001). Primiparity, prolonged second stage and occipito-posterior presentation were also found to be significant risk factors for failed vacuum extraction. In this study, we found that large head circumference was associated with vacuum extraction failure rather than high birth weight.
Development of a Modified Vacuum Cleaner for Lunar Surface Systems
NASA Technical Reports Server (NTRS)
Toon, Katherine P.; Lee, Steve A.; Edgerly, Rachel D.
2009-01-01
The National Aeronautics and Space Administration (NASA) mission to expand space exploration will return humans to the Moon with the goal of maintaining a long-term presence. One challenge that NASA will face returning to the Moon is managing the lunar regolith found on the Moon's surface, which will collect on extravehicular activity (EVA) suits and other equipment. Based on the Apollo experience, the issues astronauts encountered with lunar regolith included eye/lung irritation, and various hardware failures (seals, screw threads, electrical connectors and fabric contamination), which were all related to inadequate lunar regolith mitigation. A vacuum cleaner capable of detaching, transferring, and efficiently capturing lunar regolith has been proposed as a method to mitigate the lunar regolith problem in the habitable environment on lunar surface. In order to develop this vacuum, a modified "off-the-shelf" vacuum cleaner has been used to determine detachment efficiency, vacuum requirements, and optimal cleaning techniques to ensure efficient dust removal in habitable lunar surfaces, EVA spacesuits, and air exchange volume. During the initial development of the Lunar Surface System vacuum cleaner, systematic testing was performed with varying flow rates on multiple surfaces (fabrics and metallics), atmospheric (14.7 psia) and reduced pressures (10.2 and 8.3 psia), different vacuum tool attachments, and several vacuum cleaning techniques to determine the performance requirements for the vacuum cleaner. The data recorded during testing was evaluated by calculating percent removal, relative to the retained simulant on the tested surface. In addition, Scanning Electron Microscopy (SEM) imaging was used to determine particle size distribution retained on the surface. The scope of this paper is to explain the initial phase of vacuum cleaner development, including historical Apollo mission data, current state-of-the-art vacuum cleaner technology, and vacuum cleaner
Development of a Modified Vacuum Cleaner for Lunar Surface Systems
NASA Technical Reports Server (NTRS)
Toon, Katherine P.; Lee, Steve A.; Edgerly, Rachel D.
2010-01-01
The National Aeronautics and Space Administration (NASA) mission to expand space exploration will return humans to the Moon with the goal of maintaining a long-term presence. One challenge that NASA will face returning to the Moon is managing the lunar regolith found on the Moon's surface, which will collect on extravehicular activity (EVA) suits and other equipment. Based on the Apollo experience, the issues astronauts encountered with lunar regolith included eye/lung irritation, and various hardware failures (seals, screw threads, electrical connectors and fabric contamination), which were all related to inadequate lunar regolith mitigation. A vacuum cleaner capable of detaching, transferring, and efficiently capturing lunar regolith has been proposed as a method to mitigate the lunar regolith problem in the habitable environment on lunar surface. In order to develop this vacuum, a modified "off-the-shelf' vacuum cleaner will be used to determine detachment efficiency, vacuum requirements, and optimal cleaning techniques to ensure efficient dust removal in habitable lunar surfaces, EVA spacesuits, and air exchange volume. During the initial development of the Lunar Surface System vacuum cleaner, systematic testing was performed with varying flow rates on multiple surfaces (fabrics and metallics), atmospheric (14.7 psia) and reduced pressures (10.2 and 8.3 psia), different vacuum tool attachments, and several vacuum cleaning techniques in order to determine the performance requirements for the vacuum cleaner. The data recorded during testing was evaluated by calculating particulate removal, relative to the retained simulant on the tested surface. In addition, optical microscopy was used to determine particle size distribution retained on the surface. The scope of this paper is to explain the initial phase of vacuum cleaner development, including historical Apollo mission data, current state-of-the-art vacuum cleaner technology, and vacuum cleaner testing that has
Flexible Composite-Material Pressure Vessel
NASA Technical Reports Server (NTRS)
Brown, Glen; Haggard, Roy; Harris, Paul A.
2003-01-01
A proposed lightweight pressure vessel would be made of a composite of high-tenacity continuous fibers and a flexible matrix material. The flexibility of this pressure vessel would render it (1) compactly stowable for transport and (2) more able to withstand impacts, relative to lightweight pressure vessels made of rigid composite materials. The vessel would be designed as a structural shell wherein the fibers would be predominantly bias-oriented, the orientations being optimized to make the fibers bear the tensile loads in the structure. Such efficient use of tension-bearing fibers would minimize or eliminate the need for stitching and fill (weft) fibers for strength. The vessel could be fabricated by techniques adapted from filament winding of prior composite-material vessels, perhaps in conjunction with the use of dry film adhesives. In addition to the high-bias main-body substructure described above, the vessel would include a low-bias end substructure to complete coverage and react peak loads. Axial elements would be overlaid to contain damage and to control fiber orientation around side openings. Fiber ring structures would be used as interfaces for connection to ancillary hardware.
Vacuum Plasma Spraying Replaces Electrodeposition
NASA Technical Reports Server (NTRS)
Holmes, Richard R.; Power, Chris; Burns, David H.; Daniel, Ron; Mckechnie, Timothy N.
1992-01-01
Vacuum plasma spraying used to fabricate large parts with complicated contours and inner structures, without uninspectable welds. Reduces time, and expense of fabrication. Wall of combustion chamber built up inside of outer nickel-alloy jacket by plasma spraying. Particles of metal sprayed partially melted in plasma gun and thrown at supersonic speed toward deposition surface. Vacuum plasma-spray produces stronger bond between the grooves and covering layer completing channels and wall of combustion chamber. In tests, bond withstood pressure of 20 kpsi, three times allowable limit by old method.
Traction force during vacuum extraction: a prospective observational study.
Pettersson, K; Ajne, J; Yousaf, K; Sturm, D; Westgren, M; Ajne, G
2015-12-01
To investigate the traction force employed during vacuum extractions. Observational cross-sectional study. Obstetric Department, Karolinska University Hospital, Sweden, and the Swedish National Congress of Obstetrics and Gynaecology, 2013. Two hundred women with vacuum extraction at term and 130 obstetricians participating in a simulated setting. In a normal clinical setting, we used a specially adapted device to measure and record the force used to undertake vacuum extraction. In a subsequent part of the study, the force employed for vacuum extraction by a group of obstetricians in a fictive setting was estimated and objectively measured. Applied force during vacuum extraction in relation to the estimated level of difficulty in the delivery; perinatal diagnoses of asphyxia or head trauma; estimated force compared with objectively measured force employed in the fictive setting. The median (minimum-maximum) peak forces for minimum, average and excessive vacuum extraction in the clinical setting were 176 N (5-360 N), 225 N (115-436 N), and 241 N (164-452 N), respectively. In 34% of cases a force in excess of 216 N was employed. There was no correlation between the umbilical arterial pH at delivery and the traction force employed during extraction. Four cases of mild hypoxic ischaemic encephalopathy were observed, three of which were associated with a delivery whereby excessive traction force was employed during the vacuum extraction. In the fictive setting, the actual exerted force was twice the quantitative estimation. The measured forces in the clinical setting were four times higher than that estimated in the fictive setting. Higher than expected levels of traction force were used for vacuum extraction delivery. As obstetricians tend to underestimate the force applied during vacuum extraction, objective measurement with instantaneous feedback may be valuable in raising awareness. © 2015 Royal College of Obstetricians and Gynaecologists.