High Vacuum Creep Facility in the Materials Processing Laboratory

NASA Image and Video Library

1973-01-21

Technicians at work in the Materials Processing Laboratory’s Creep Facility at the National Aeronautics and Space Administration (NASA) Lewis Research Center. The technicians supported the engineers’ studies of refractory materials, metals, and advanced superalloys. The Materials Processing Laboratory contained laboratories and test areas equipped to prepare and develop these metals and materials. The ultra-high vacuum lab, seen in this photograph, contained creep and tensile test equipment. Creep testing is used to study a material’s ability to withstand long durations under constant pressure and temperatures. The equipment measured the strain over a long period of time. Tensile test equipment subjects the test material to strain until the material fails. The two tests were used to determine the strength and durability of different materials. The Materials Processing Laboratory also housed arc and electron beam melting furnaces, a hydraulic vertical extrusion press, compaction and forging equipment, and rolling mills and swagers. There were cryogenic and gas storage facilities and mechanical and oil diffusion vacuum pumps. The facility contained both instrumental and analytical chemistry laboratories for work on radioactive or toxic materials and the only shop to machine toxic materials in the Midwest.

Space simulation facilities providing a stable thermal vacuum facility

NASA Technical Reports Server (NTRS)

Tellalian, Martin L.

1990-01-01

CBI has recently constructed the Intermediate Thermal Vacuum Facility. Built as a corporate facility, the installation will first be used on the Boost Surveillance and Tracking System (BSTS) program. It will also be used to develop and test other sensor systems. The horizontal chamber has a horseshoe shaped cross section and is supported on pneumatic isolators for vibration isolation. The chamber structure was designed to meet stability and stiffness requirements. The design process included measurement of the ambient ground vibrations, analysis of various foundation test article support configurations, design and analysis of the chamber shell and modal testing of the chamber shell. A detailed 3-D finite element analysis was made in the design stage to predict the lowest three natural frequencies and mode shapes and to identify local vibrating components. The design process is described and the results are compared of the finite element analysis to the results of the field modal testing and analysis for the 3 lowest natural frequencies and mode shapes. Concepts are also presented for stiffening large steel structures along with methods to improve test article stability in large space simulation facilities.

Cold Vacuum Drying facility civil structural system design description (SYS 06)

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

PITKOFF, C.C.

This document describes the Cold Vacuum Drying (CVD) Facility civil - structural system. This system consists of the facility structure, including the administrative and process areas. The system's primary purpose is to provide for a facility to house the CVD process and personnel and to provide a tertiary level of containment. The document provides a description of the facility and demonstrates how the design meets the various requirements imposed by the safety analysis report and the design requirements document.

The target vacuum storage facility at iThemba LABS

NASA Astrophysics Data System (ADS)

Neveling, R.; Kheswa, N. Y.; Papka, P.

2018-05-01

A number of nuclear physics experiments at iThemba LABS require target foils that consist of specific isotopes of elements which are reactive in air. Not only is it important to prepare these targets in a suitable environment to prevent oxidation, but consideration should also be given to the long term storage and handling facilities of such targets. The target vacuum storage facility at iThemba LABS, as well as additional hardware necessary to transport and install the target foils in the experimental chamber, will be discussed.

ISRU Soil Mechanics Vacuum Facility: Soil Bin Preparation and Simulant Strength Characterization

NASA Technical Reports Server (NTRS)

Kleinhenz, Julie; Wilkinson, Allen

2012-01-01

Testing in relevant environments is key to exploration mission hardware development. This is true on both the component level (in early development) and system level (in late development stages). During ISRU missions the hardware will interface with the soil (digging, roving, etc) in a vacuum environment. A relevant test environment will therefore involve a vacuum chamber with a controlled, conditioned simulant bed. However, in earth-based granular media, such as lunar soil simulant, gases trapped within the material pore structures and water adsorbed to all particle surfaces will release when exposed to vacuum. Early vacuum testing has shown that this gas release can occur violently, which loosens and weakens the simulant, altering the consolidation state. The Vacuum Facility #13, a mid-size chamber (3.66m tall, 1.5m inner diameter) at the NASA Glenn Research Center has been modified to create a soil mechanics test facility. A 0.64m deep by 0.914m square metric ton bed of lunar simulant was placed under vacuum using a variety of pumping techniques. Both GRC-3 and LHT-3M simulant types have been used. An electric cone penetrometer was used to measure simulant strength properties at vacuum including: cohesion, friction angle, bulk density and shear modulus. Simulant disruptions, caused by off gassing, affected the strength properties, but could be mitigated by reducing pump rate. No disruptions were observed at pressures below 2.5Torr, regardless of the pump rate. However, slow off gassing of the soil lead to long test times, a full week, to reach 10-5Torr. This work highlights the need for robotic machine-simulant hardware and operations in vacuum to expeditiously perform (sub-)systems tests.

Vacuum Radiance-Temperature Standard Facility for Infrared Remote Sensing at NIM

NASA Astrophysics Data System (ADS)

Hao, X. P.; Song, J.; Xu, M.; Sun, J. P.; Gong, L. Y.; Yuan, Z. D.; Lu, X. F.

2018-06-01

As infrared remote sensors are very important parts of Earth observation satellites, they must be calibrated based on the radiance temperature of a blackbody in a vacuum chamber prior to launch. The uncertainty of such temperature is thus an essential component of the sensors' uncertainty. This paper describes the vacuum radiance-temperature standard facility (VRTSF) at the National Institute of Metrology of China, which will serve to calibrate infrared remote sensors on Chinese meteorological satellites. The VRTSF can be used to calibrate vacuum blackbody radiance temperature, including those used to calibrate infrared remote sensors. The components of the VRTSF are described in this paper, including the VMTBB, the LNBB, the FTIR spectrometer, the reduced-background optical system, the vacuum chamber used to calibrate customers' blackbody, the vacuum-pumping system and the liquid-nitrogen-support system. The experimental methods and results are expounded. The uncertainty of the radiance temperature of VMTBB is 0.026 °C at 30 °C over 10 μm.

2-kW Solar Dynamic Space Power System Tested in Lewis' Thermal Vacuum Facility

NASA Technical Reports Server (NTRS)

1995-01-01

Working together, a NASA/industry team successfully operated and tested a complete solar dynamic space power system in a large thermal vacuum facility with a simulated sun. This NASA Lewis Research Center facility, known as Tank 6 in building 301, accurately simulates the temperatures, high vacuum, and solar flux encountered in low-Earth orbit. The solar dynamic space power system shown in the photo in the Lewis facility, includes the solar concentrator and the solar receiver with thermal energy storage integrated with the power conversion unit. Initial testing in December 1994 resulted in the world's first operation of an integrated solar dynamic system in a relevant environment.

Design and performance of vacuum system for high heat flux test facility

NASA Astrophysics Data System (ADS)

Swamy Kidambi, Rajamannar; Mokaria, Prakash; Khirwadkar, Samir; Belsare, Sunil; Khan, M. S.; Patel, Tushar; Krishnan, Deepu S.

2017-04-01

High heat flux test facility (HHFTF) at IPR is used for testing thermal performance of plasma facing materials or components. It consists of various subsystems like vacuum system, high power electron beam system, diagnostic and calibration system, data acquisition and control system and high pressure high temperature water circulation system. Vacuum system consists of large D-shaped chamber, target handling system, pumping systems and support structure. The net volume of vacuum chamber is 5 m3 was maintained at the base pressure of the order of 10-6 mbar for operation of electron gun with minimum beam diameter which is achieved with turbo-molecular pump (TMP) and cryo pump. A variable conductance gate valve is used for maintaining required vacuum in the chamber. Initial pumping of the chamber was carried out by using suitable rotary and root pumps. PXI and PLC based faster real time data acquisition and control system is implemented for performing the various operations like remote operation, online vacuum data measurements, display and status indication of all vacuum equipments. This paper describes in detail the design and implementation of various vacuum system for HHFTF.

Proposed Facility Modifications to Support Propulsion Systems Testing Under Simulated Space Conditions at Plum Brook Station's Spacecraft Propulsion Research Facility (B-2)

NASA Technical Reports Server (NTRS)

Edwards, Daryl A.

2008-01-01

Preparing NASA's Plum Brook Station's Spacecraft Propulsion Research Facility (B-2) to support NASA's new generation of launch vehicles has raised many challenges for B-2's support staff. The facility provides a unique capability to test chemical propulsion systems/vehicles while simulating space thermal and vacuum environments. Designed and constructed in the early 1960s to support upper stage cryogenic engine/vehicle system development, the Plum Brook Station B-2 facility will require modifications to support the larger, more powerful, and more advanced engine systems for the next generation of vehicles leaving earth's orbit. Engine design improvements over the years have included large area expansion ratio nozzles, greater combustion chamber pressures, and advanced materials. Consequently, it has become necessary to determine what facility changes are required and how the facility can be adapted to support varying customers and their specific test needs. Exhaust system performance, including understanding the present facility capabilities, is the primary focus of this work. A variety of approaches and analytical tools are being employed to gain this understanding. This presentation discusses some of the challenges in applying these tools to this project and expected facility configuration to support the varying customer needs.

Proposed Facility Modifications to Support Propulsion Systems Testing Under Simulated Space Conditions at Plum Brook Station's Spacecraft Propulsion Research Facility (B-2)

NASA Technical Reports Server (NTRS)

Edwards, Daryl A.

2007-01-01

Preparing NASA's Plum Brook Station's Spacecraft Propulsion Research Facility (B-2) to support NASA's new generation of launch vehicles has raised many challenges for B-2 s support staff. The facility provides a unique capability to test chemical propulsion systems/vehicles while simulating space thermal and vacuum environments. Designed and constructed 4 decades ago to support upper stage cryogenic engine/vehicle system development, the Plum Brook Station B-2 facility will require modifications to support the larger, more powerful, and more advanced engine systems for the next generation of vehicles leaving earth's orbit. Engine design improvements over the years have included large area expansion ratio nozzles, greater combustion chamber pressures, and advanced materials. Consequently, it has become necessary to determine what facility changes are required and how the facility can be adapted to support varying customers and their specific test needs. Instrumental in this task is understanding the present facility capabilities and identifying what reasonable changes can be implemented. A variety of approaches and analytical tools are being employed to gain this understanding. This paper discusses some of the challenges in applying these tools to this project and expected facility configuration to support the varying customer needs.

Development and Testing of an ISRU Soil Mechanics Vacuum Test Facility

NASA Technical Reports Server (NTRS)

Kleinhenz, Julie E.; Wilkinson, R. Allen

2014-01-01

For extraterrestrial missions, earth based testing in relevant environments is key to successful hardware development. This is true for both early component level development and system level integration. For In-Situ Resource Utilization (ISRU) on the moon, hardware must interface with the surface material, or regolith, in a vacuum environment. A relevant test environment will therefore involve a vacuum chamber with a controlled, properly conditioned bed of lunar regolith simulant. However, in earth-based granular media, such as lunar regolith simulant, gases trapped within the material pore structures and water adsorbed to all particle surfaces will release when exposed to vacuum. Early vacuum testing has shown that this gas release can occur violently, which loosens and weakens the simulant, altering the consolidation state. A mid-size chamber (3.66 m tall, 1.5 m inner diameter) at the NASA Glenn Research Center has been modified to create a soil mechanics test facility. A 0.64 m deep by 0.914 m square metric ton bed of lunar simulant was placed under vacuum using a variety of pumping techniques. Both GRC-3 and LHT-3M simulant types were used. Data obtained from an electric cone penetrometer can be used to determine strength properties at vacuum including: cohesion, friction angle, bulk density and shear modulus. Simulant disruptions, caused by off-gassing, affected the strength properties, but could be mitigated by reducing pump rate. No disruptions were observed at pressures below 2.5 Torr, regardless of the pump rate. The slow off-gassing of the soil at low pressure lead to long test times; a full week to reach 10(exp -5) Torr. Robotic soil manipulation would enable multiple ISRU hardware test within the same vacuum cycle. The feasibility of a robotically controlled auger and tamper was explored at vacuum conditions.

Centaur Rocket in Space Propulsion Research Facility (B-2)

NASA Image and Video Library

1969-07-21

A Centaur second-stage rocket in the Space Propulsion Research Facility, better known as B‒2, operating at NASA’s Plum Brook Station in Sandusky, Ohio. Centaur was designed to be used with an Atlas booster to send the Surveyor spacecraft to the moon in the mid-1960s. After those missions, the rocket was modified to launch a series of astronomical observation satellites into orbit and send space probes to other planets. Researchers conducted a series of systems tests at the Plum Brook test stands to improve the Centaur fuel pumping system. Follow up full-scale tests in the B-2 facility led to the eventual removal of the boost pumps from the design. This reduced the system’s complexity and significantly reduced the cost of a Centaur rocket. The Centaur tests were the first use of the new B-2 facility. B‒2 was the world's only high altitude test facility capable of full-scale rocket engine and launch vehicle system level tests. It was created to test rocket propulsion systems with up to 100,000 pounds of thrust in a simulated space environment. The facility has the unique ability to maintain a vacuum at the rocket’s nozzle while the engine is firing. The rocket fires into a 120-foot deep spray chamber which cools the exhaust before it is ejected outside the facility. B‒2 simulated space using giant diffusion pumps to reduce chamber pressure 10-6 torr, nitrogen-filled cold walls create cryogenic temperatures, and quartz lamps replicate the radiation of the sun.

Characterization of Vacuum Facility Background Gas Through Simulation and Considerations for Electric Propulsion Ground Testing

NASA Technical Reports Server (NTRS)

Yim, John T.; Burt, Jonathan M.

2015-01-01

The background gas in a vacuum facility for electric propulsion ground testing is examined in detail through a series of cold flow simulations using a direct simulation Monte Carlo (DSMC) code. The focus here is on the background gas itself, its structure and characteristics, rather than assessing its interaction and impact on thruster operation. The background gas, which is often incorrectly characterized as uniform, is found to have a notable velocity within a test facility. The gas velocity has an impact on the proper measurement of pressure and the calculation of ingestion flux to a thruster. There are also considerations for best practices for tests that involve the introduction of supplemental gas flows to artificially increase the background pressure. All of these effects need to be accounted for to properly characterize the operation of electric propulsion thrusters across different ground test vacuum facilities.

Facility and Methods Developed for Simulated Space Vacuum Ultraviolet Exposure Testing of Polymer Films

NASA Technical Reports Server (NTRS)

Dever, Joyce A.; Pietromica, Anthony J.; Stueber, Thomas J.; Sechkar, Edward A.; Messer, Russell K.

2002-01-01

Vacuum ultraviolet (VUV) radiation of wavelengths between 115 and 200 nm produced by the Sun in the space environment can degrade polymer films, producing changes in their optical, mechanical, and chemical properties. These effects are particularly important for thin polymer films being considered for ultralightweight space structures, because, for most polymers, VUV radiation is absorbed in a thin surface layer. The NASA Glenn Research Center has developed facilities and methods for long-term ground testing of polymer films to evaluate space environmental VUV radiation effects. VUV exposure can also be used as part of combined or sequential simulated space environmental exposures to determine combined damaging effects with other aspects of the space environment, which include solar ultraviolet radiation, solar flare x-rays, electron and proton radiation, atomic oxygen (for low-Earth-orbit missions), and temperature effects. Because the wavelength sensitivity of VUV damage is not well known for most materials, Glenn's VUV facility uses a broad-spectrum deuterium lamp with a magnesium fluoride window that provides output between 115 and 200 nm. Deuterium lamps of this type were characterized by the National Institute of Standards and Technology and through measurements at Glenn. Spectral irradiance measurements show that from approximately 115 to 160 nm, deuterium lamp irradiance can be many times that of air mass zero solar irradiance, and as wavelength increases above approximately 160 nm, deuterium lamp irradiance decreases in comparison to the Sun. The facility is a cryopumped vacuum chamber that achieves a system pressure of approximately 5310(exp -6) torr. It contains four individual VUV-exposure compartments in vacuum, separated by water-cooled copper walls to minimize VUV radiation and any sample contamination cross interactions between compartments. Each VUV-exposure compartment contains a VUV deuterium lamp, a motor-controlled sample stage coupled with a

Changes in CR-39 proton sensitivity due to prolonged exposure to high vacuums relevant to the National Ignition Facility and OMEGA.

PubMed

Manuel, M J-E; Rosenberg, M J; Sinenian, N; Rinderknecht, H; Zylstra, A B; Séguin, F H; Frenje, J; Li, C K; Petrasso, R D

2011-09-01

When used at facilities like OMEGA and the NIF, CR-39 is exposed to high vacuum environments before and after irradiation by charged particles and neutrons. Using an electrostatic linear accelerator at MIT, studies have been conducted to investigate the effects of high vacuum exposure on the sensitivity of CR-39 to fusion protons in the ~1-9 MeV energy range. High vacuum conditions, of order 10(-5) Torr, experienced by CR-39 samples at these facilities were emulated. It is shown that vacuum exposure times longer than ~16 h before proton irradiation result in a decrease in proton sensitivity, whereas no effect was observed for up to 67 h of vacuum exposure after proton irradiation. CR-39 sensitivity curves are presented for samples with prolonged exposure to high vacuum before and after proton irradiation. © 2011 American Institute of Physics

Axicabtagene ciloleucel (KTE-C19), an anti-CD19 CAR T therapy for the treatment of relapsed/refractory aggressive B-cell non-Hodgkin's lymphoma.

PubMed

Jain, Michael D; Bachmeier, Christina A; Phuoc, Vania H; Chavez, Julio C

2018-01-01

Adoptive T-cell immunotherapy is a rapidly growing field and is shifting the paradigm of clinical cancer treatment. Axicabtagene ciloleucel (axi-cel) is an anti-CD19 chimeric antigen receptor T-cell therapy that was initially developed at the National Cancer Institute and has recently been commercially approved by the US Food and Drug Administration for relapsed or refractory aggressive non-Hodgkin's lymphomas including diffuse large B-cell lymphoma and its variants. The ZUMA-1 Phase I and II clinical trials formed the basis of the US Food and Drug Administration approval of this product, and we discuss the particulars of the clinical trials and the pharmacology of axi-cel. In addition, we review the CD19 chimeric antigen receptor T-specific toxicities of cytokine release syndrome and neurotoxicity, which remain the challenges to the safe delivery of this important therapy for aggressive B-cell lymphomas with poor prognosis.

[Sterilization effect analysis of B-class pulsation table top vacuum sterilizer to dental handpieces].

PubMed

Zeng, Shu-Rong; Jiang, Bo; Xiao, Xiao-Rong

2007-06-01

Discuss sterilization effect of B-class pulsation table top vacuum pressure steam sterilizer for dental handpiece. Analysis selection of sterilizer for dental handpiece and sterilization management processes and sterilization effect monitoring, evaluation of monitoring result and effective sterilization method. The B-class pulsation table top vacuum pressure steam sterilizer to dental handpiece in West China Stomatological Hospital of Sichuan University met the requirement of the chemical and biological monitoring. Its efficiency of sterilization was 100%. The results of aerobic culture, anaerobic culture, B-type hepatitis mark monitoring to sterilized dental handpiece were negative. It is effective method for dental handpiece sterilization to use B-class pulsation table top vacuum pressure steam sterilizer.

Axicabtagene ciloleucel (KTE-C19), an anti-CD19 CAR T therapy for the treatment of relapsed/refractory aggressive B-cell non-Hodgkin’s lymphoma

PubMed Central

Jain, Michael D; Bachmeier, Christina A; Phuoc, Vania H; Chavez, Julio C

2018-01-01

Adoptive T-cell immunotherapy is a rapidly growing field and is shifting the paradigm of clinical cancer treatment. Axicabtagene ciloleucel (axi-cel) is an anti-CD19 chimeric antigen receptor T-cell therapy that was initially developed at the National Cancer Institute and has recently been commercially approved by the US Food and Drug Administration for relapsed or refractory aggressive non-Hodgkin’s lymphomas including diffuse large B-cell lymphoma and its variants. The ZUMA-1 Phase I and II clinical trials formed the basis of the US Food and Drug Administration approval of this product, and we discuss the particulars of the clinical trials and the pharmacology of axi-cel. In addition, we review the CD19 chimeric antigen receptor T-specific toxicities of cytokine release syndrome and neurotoxicity, which remain the challenges to the safe delivery of this important therapy for aggressive B-cell lymphomas with poor prognosis. PMID:29910620

Simulation of the synergistic low Earth orbit effects of vacuum thermal cycling, vacuum UV radiation, and atomic oxygen

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.

Space ultra-vacuum facility and method of operation

NASA Technical Reports Server (NTRS)

Naumann, Robert J. (Inventor)

1986-01-01

A wake shield facility providing an ultrahigh vacuum level for space processing is described. The facility is in the shape of a truncated, hollow hemispherical section, one side of the shield convex and the other concave. The shield surface is preferably made of material that has low out-gassing characteristics such as stainless steel. A material sample supporting fixture in the form of a carousel is disposed on the convex side of the shield at its apex. Movable arms, also on the convex side, are connected by the shield in proximity to the carousel, the arms supporting processing fixtures, and providing for movement of the fixtures to predetermined locations required for producing interations with material samples. For MBE processes a vapor jet projects a stream of vaporized material onto a sample surface. The fixtures are oriented to face the surface of the sample being processed when in their extended position, and when not in use they are retractable to a storage position. The concave side of the shield has a support structure including metal struts connected to the shield, extending radially inward. The struts are joined to an end plate disposed parallel to the outer edge of the shield. This system eliminates outgassing contamination.

Mathematical Models of IABG Thermal-Vacuum Facilities

NASA Astrophysics Data System (ADS)

Doring, Daniel; Ulfers, Hendrik

2014-06-01

IABG in Ottobrunn, Germany, operates thermal-vacuum facilities of different sizes and complexities as a service for space-testing of satellites and components. One aspect of these tests is the qualification of the thermal control system that keeps all onboard components within their save operating temperature band. As not all possible operation / mission states can be simulated within a sensible test time, usually a subset of important and extreme states is tested at TV facilities to validate the thermal model of the satellite, which is then used to model all other possible mission states. With advances in the precision of customer thermal models, simple assumptions of the test environment (e.g. everything black & cold, one solar constant of light from this side) are no longer sufficient, as real space simulation chambers do deviate from this ideal. For example the mechanical adapters which support the spacecraft are usually not actively cooled. To enable IABG to provide a model that is sufficiently detailed and realistic for current system tests, Munich engineering company CASE developed ESATAN models for the two larger chambers. CASE has many years of experience in thermal analysis for space-flight systems and ESATAN. The two models represent the rather simple (and therefore very homogeneous) 3m-TVA and the extremely complex space simulation test facility and its solar simulator. The cooperation of IABG and CASE built up extensive knowledge of the facilities thermal behaviour. This is the key to optimally support customers with their test campaigns in the future. The ESARAD part of the models contains all relevant information with regard to geometry (CAD data), surface properties (optical measurements) and solar irradiation for the sun simulator. The temperature of the actively cooled thermal shrouds is measured and mapped to the thermal mesh to create the temperature field in the ESATAN part as boundary conditions. Both models comprise switches to easily

Space ultra-vacuum facility and method of operation

NASA Technical Reports Server (NTRS)

Naumann, Robert J. (Inventor)

1988-01-01

A wake shield space processing facility (10) for maintaining ultra-high levels of vacuum is described. The wake shield (12) is a truncated hemispherical section having a convex side (14) and a concave side (24). Material samples (68) to be processed are located on the convex side of the shield, which faces in the wake direction in operation in orbit. Necessary processing fixtures (20) and (22) are also located on the convex side. Support equipment including power supplies (40, 42), CMG package (46) and electronic control package (44) are located on the convex side (24) of the shield facing the ram direction. Prior to operation in orbit the wake shield is oriented in reverse with the convex side facing the ram direction to provide cleaning by exposure to ambient atomic oxygen. The shield is then baked-out by being pointed directed at the sun to obtain heating for a suitable period.

Electroweak vacuum stability in classically conformal B - L extension of the standard model

DOE PAGES

Das, Arindam; Okada, Nobuchika; Papapietro, Nathan

2017-02-23

Here, we consider the minimal U(1) B - L extension of the standard model (SM) with the classically conformal invariance, where an anomaly-free U(1) B - L gauge symme- try is introduced along with three generations of right-handed neutrinos and a U(1) B - L Higgs field. Because of the classi- cally conformal symmetry, all dimensional parameters are forbidden. The B - L gauge symmetry is radiatively bro- ken through the Coleman–Weinberg mechanism, generating the mass for the U(1) B - L gauge boson (Z' boson) and the right-handed neutrinos. Through a small negative coupling betweenmore » the SM Higgs doublet and the B - L Higgs field, the negative mass term for the SM Higgs doublet is gener- ated and the electroweak symmetry is broken. We investigate the electroweak vacuum instability problem in the SM in this model context. It is well known that in the classically conformal U(1) B - L extension of the SM, the electroweak vacuum remains unstable in the renormalization group anal- ysis at the one-loop level. In this paper, we extend the anal- ysis to the two-loop level, and perform parameter scans. We also identify a parameter region which not only solve the vacuum instability problem, but also satisfy the recent ATLAS and CMS bounds from search for Z ' boson resonance at the LHC Run-2. Considering self-energy corrections to the SM Higgs doublet through the right-handed neutrinos and the Z ' boson, we derive the naturalness bound on the model parameters to realize the electroweak scale without fine-tunings.« less

Electroweak vacuum stability in classically conformal B - L extension of the standard model

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

Das, Arindam; Okada, Nobuchika; Papapietro, Nathan

Here, we consider the minimal U(1) B - L extension of the standard model (SM) with the classically conformal invariance, where an anomaly-free U(1) B - L gauge symme- try is introduced along with three generations of right-handed neutrinos and a U(1) B - L Higgs field. Because of the classi- cally conformal symmetry, all dimensional parameters are forbidden. The B - L gauge symmetry is radiatively bro- ken through the Coleman–Weinberg mechanism, generating the mass for the U(1) B - L gauge boson (Z' boson) and the right-handed neutrinos. Through a small negative coupling betweenmore » the SM Higgs doublet and the B - L Higgs field, the negative mass term for the SM Higgs doublet is gener- ated and the electroweak symmetry is broken. We investigate the electroweak vacuum instability problem in the SM in this model context. It is well known that in the classically conformal U(1) B - L extension of the SM, the electroweak vacuum remains unstable in the renormalization group anal- ysis at the one-loop level. In this paper, we extend the anal- ysis to the two-loop level, and perform parameter scans. We also identify a parameter region which not only solve the vacuum instability problem, but also satisfy the recent ATLAS and CMS bounds from search for Z ' boson resonance at the LHC Run-2. Considering self-energy corrections to the SM Higgs doublet through the right-handed neutrinos and the Z ' boson, we derive the naturalness bound on the model parameters to realize the electroweak scale without fine-tunings.« less

SNS Cryogenic Test Facility Kinney Vacuum Pump Commissioning and Operation at 2 K

NASA Astrophysics Data System (ADS)

DeGraff, B.; Howell, M.; Kim, S.; Neustadt, T.

2017-12-01

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) has built and commissioned an independent Cryogenic Test Facility (CTF) in support of testing in the Radio-frequency Test Facility (RFTF). Superconducting Radio-frequency Cavity (SRF) testing was initially conducted with the CTF cold box at 4.5 K. A Kinney vacuum pump skid consisting of a roots blower with a liquid ring backing pump was recently added to the CTF system to provide testing capabilities at 2 K. System design, pump refurbishment and installation of the Kinney pump will be presented. During the commissioning and initial testing period with the Kinney pump, several barriers to achieve reliable operation were experienced. Details of these lessons learned and improvements to skid operations will be presented. Pump capacity data will also be presented.

Phase Formation and Superconductivity of Fe-TUBE Encapsulated and Vacuum-Annealed MgB2

NASA Astrophysics Data System (ADS)

Singh, K. P.; Awana, V. P. S.; Shahabuddin, Md.; Husain, M.; Saxena, R. B.; Nigam, Rashmi; Ansari, M. A.; Gupta, Anurag; Narayan, Himanshu; Halder, S. K.; Kishan, H.

We report optimization of the synthesis parameters viz. heating temperature (TH), and hold time (thold) for vacuum-annealed (10-5 Torr) and LN2 (liquid nitrogen) quenched MgB2 compound. These are single-phase compounds crystallizing in the hexagonal structure (space group P6/mmm) at room temperature. Our XRD results indicated that for phase-pure MgB2, the TH for 10-5 Torr annealed and LN2-quenched samples is 750°C. The right stoichiometry i.e., MgB2 of the compound corresponding to 10-5 Torr and TH of 750°C is found for the hold time (thold) of 2.30 hours. With varying thold from 1-4 hours at fixed TH (750°C) and vacuum (10-5 Torr), the c-lattice parameter decreases first and later increases with thold (hours) before a near saturation, while the a-lattice parameter first increases and later decreases beyond a thold of 2.30 hours. The c/a ratio versus thold plot showed an inverted bell-shaped curve, touching the lowest value of 1.141, which is the reported value for perfect stoichiometry of MgB2. The optimized stoichimetric MgB2 compound exhibited superconductivity at 39.2 K with a transition width of 0.6 K. In conclusion, the synthesis parameters for phase pure stoichimetric vacuum-annealed MgB2 compound are optimized and are compared with widely-reported Ta tube encapsulated samples.

SNS Cryogenic Test Facility Kinney Vacuum Pump Commissioning and Operation at 2 K

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

Degraff, Brian D.; Howell, Matthew P.; Kim, Sang-Ho

The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) has built and commissioned an independent Cryogenic Test Facility (CTF) in support of testing in the Radio-frequency Test Facility (RFTF). Superconducting Radio-frequency Cavity (SRF) testing was initially conducted with the CTF cold box at 4.5 K. A Kinney vacuum pump skid consisting of a roots blower with a liquid ring backing pump was recently added to the CTF system to provide testing capabilities at 2 K. System design, pump refurbishment and installation of the Kinney pump will be presented. During the commissioning and initial testing period with the Kinneymore » pump, several barriers to achieve reliable operation were experienced. Details of these lessons learned and improvements to skid operations will be presented. Pump capacity data will also be presented.« less

A large high vacuum, high pumping speed space simulation chamber for electric propulsion

NASA Technical Reports Server (NTRS)

Grisnik, Stanley P.; Parkes, James E.

1994-01-01

Testing high power electric propulsion devices poses unique requirements on space simulation facilities. Very high pumping speeds are required to maintain high vacuum levels while handling large volumes of exhaust products. These pumping speeds are significantly higher than those available in most existing vacuum facilities. There is also a requirement for relatively large vacuum chamber dimensions to minimize facility wall/thruster plume interactions and to accommodate far field plume diagnostic measurements. A 4.57 m (15 ft) diameter by 19.2 m (63 ft) long vacuum chamber at NASA Lewis Research Center is described. The chamber utilizes oil diffusion pumps in combination with cryopanels to achieve high vacuum pumping speeds at high vacuum levels. The facility is computer controlled for all phases of operation from start-up, through testing, to shutdown. The computer control system increases the utilization of the facility and reduces the manpower requirements needed for facility operations.

Vacuum mechatronics

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.

Improved Vacuum Bazooka

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!

A new thermal vacuum facility at the Martin Marietta Waterton plant

NASA Technical Reports Server (NTRS)

Watson, Robert N.; Bonn, John W.

1992-01-01

A new thermal-vacuum facility has been recently completed at the Martin Marietta Waterton plant near Denver, Colorado. The facility was designed, fabricated, installed, and tested as a turn-key project by Pitt-Des Moines Inc. and CVI Inc. The chamber has a 5.49 M by 6.10 M (18 ft by 20 ft) flat floor and a half-cylindrical roof with a diameter of 5.49 M (18 ft). Both ends of the chamber have full cross section doors, with one equipped with translating motors for horizontal motion. The chamber is provided with four 0.91 M (36 inches) cryopumps to obtain an ultimate pressure of 9 x 10(exp -8) Torr (Clean-Dry-Empty). The thermal shroud is designed to operate at a maximum of -179 C (-290 F) with an internal heat input of 316 MJ/Hr (300,000 BTU/Hr) using liquid nitrogen. The shroud is also designed to operate at any temperature between -156 C (-250 F) and 121 C (+250 F) using gaseous nitrogen, and heat or cool at a rate of 1.1 C (2 F) per minute.

NSLS II Vacuum System

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

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.

Chamber B Thermal/Vacuum Chamber: User Test Planning Guide

NASA Technical Reports Server (NTRS)

Montz, Mike E.

2012-01-01

Test process, milestones and inputs are unknowns to first-time users of Chamber B. The User Test Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their test engineering personnel in test planning and execution. Material covered includes a roadmap of the test process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, test article interfaces, and inputs necessary to define test scope, cost, and schedule are included as an appendix to the guide.

COR1 Engineering Test Unit Measurements at the NCAR/HAO Vacuum Tunnel Facility, October-November 2002

NASA Technical Reports Server (NTRS)

Thompson, William

2002-01-01

The Engineering Test Unit (ETU) of COR1 was made in two configurations. The first configuration, ETU-1, was for vibration testing, while the second, ETU-2, was for optical testing. This is a report on the optical testing performed on ETU-2 at the NCAR/HAO Vacuum Tunnel Facility during the months of October and November, 2002. This was the same facility used to test the two previous breadboard models. In both configurations, the first two tube sections were complete, with all optical elements aligned. The vibration model ETU-1 had the remaining tube sections attached, with mass models for the remaining optics, for the various mechanisms, and for the focal plane assembly. It was then converted into the optical model ETU-2 by removing tube sections 3 to 5, and mounting the remaining optics on commercial mounts. (The bandpass filter was also installed into tube 2, which had been replaced in ETU-1 by a mass model, so that pre- and post-vibration optical measurements could be made.) Doublet 2 was installed in a Newport LP-2 carrier, and aligned to the other optics in the first two tube sections. The LP-2 adjustment screws were then uralened so that the alignment could be maintained during shipping. Because neither the flight polarizer nor Hollow Core Motor were available, they were simulated by a commercial polarizer and rotational mount, both from Oriel corporation. The Oriel rotational stage was not designed for vacuum use, but it was determined after consultation with the company, and lab testing, that the stage could be used in the moderate vacuum conditions at the NCAR/HAO facility. The shutter and focal plane assembly were simulated with the same camera used for the previous two breadboard tests. The focal plane mask was simulated with a plane of BK7 glass with a mask glued on, using the same procedure as for the Lyot spot on Doublet 1, and mounted in an adjustable LP-2 carrier. Two masks were made, one made to the precise specifications of the optical design, the

Integrated Cryogenic Propulsion Test Article Thermal Vacuum Hotfire Testing

NASA Technical Reports Server (NTRS)

Morehead, Robert L.; Melcher, J. C.; Atwell, Matthew J.; Hurlbert, Eric A.

2017-01-01

In support of a facility characterization test, the Integrated Cryogenic Propulsion Test Article (ICPTA) was hotfire tested at a variety of simulated altitude and thermal conditions in the NASA Glenn Research Center Plum Brook Station In-Space Propulsion Thermal Vacuum Chamber (formerly B2). The ICPTA utilizes liquid oxygen and liquid methane propellants for its main engine and four reaction control engines, and uses a cold helium system for tank pressurization. The hotfire test series included high altitude, high vacuum, ambient temperature, and deep cryogenic environments, and several hundred sensors on the vehicle collected a range of system level data useful to characterize the operation of an integrated LOX/Methane spacecraft in the space environment - a unique data set for this propellant combination.

Completed Gravity Probe B Undergoes Thermal Vacuum Testing

NASA Technical Reports Server (NTRS)

2000-01-01

The Gravity Probe B (GP-B) is the relativity experiment developed at Stanford University to test two extraordinary predictions of Albert Einstein's general theory of relativity. The experiment will measure, very precisely, the expected tiny changes in the direction of the spin axes of four gyroscopes contained in an Earth-orbiting satellite at a 400-mile altitude. So free are the gyroscopes from disturbance that they will provide an almost perfect space-time reference system. They will measure how space and time are very slightly warped by the presence of the Earth, and, more profoundly, how the Earth's rotation very slightly drags space-time around with it. These effects, though small for the Earth, have far-reaching implications for the nature of matter and the structure of the Universe. In this photograph, the completed space vehicle is undergoing thermal vacuum environment testing. GP-B is among the most thoroughly researched programs ever undertaken by NASA. This is the story of a scientific quest in which physicists and engineers have collaborated closely over many years. Inspired by their quest, they have invented a whole range of technologies that are already enlivening other branches of science and engineering. Launched April 20, 2004 , the GP-B program was managed for NASA by the Marshall Space Flight Center. Development of the GP-B is the responsibility of Stanford University along with major subcontractor Lockheed Martin Corporation. (Image credit to Russ Underwood, Lockheed Martin Corporation.)

Vacuum System and Modeling for the Materials Plasma Exposure Experiment

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

Lumsdaine, Arnold; Meitner, Steve; Graves, Van

Understanding the science of plasma-material interactions (PMI) is essential for the future development of fusion facilities. The design of divertors and first walls for the next generation of long-pulse fusion facilities, such as a Fusion Nuclear Science Facility (FNSF) or a DEMO, requires significant PMI research and development. In order to meet this need, a new linear plasma facility, the Materials Plasma Exposure Experiment (MPEX) is proposed, which will produce divertor relevant plasma conditions for these next generation facilities. The device will be capable of handling low activation irradiated samples and be able to remove and replace samples without breakingmore » vacuum. A Target Exchange Chamber (TEC) which can be disconnected from the high field environment in order to perform in-situ diagnostics is planned for the facility as well. The vacuum system for MPEX must be carefully designed in order to meet the requirements of the different heating systems, and to provide conditions at the target similar to those expected in a divertor. An automated coupling-decoupling (“autocoupler”) system is designed to create a high vacuum seal, and will allow the TEC to be disconnected without breaking vacuum in either the TEC or the primary plasma materials interaction chamber. This autocoupler, which can be actuated remotely in the presence of the high magnetic fields, has been designed and prototyped, and shows robustness in a variety of conditions. The vacuum system has been modeled using a simplified finite element analysis, and indicates that the design goals for the pressures in key regions of the facility are achievable.« less

Vacuum System and Modeling for the Materials Plasma Exposure Experiment

DOE PAGES

Lumsdaine, Arnold; Meitner, Steve; Graves, Van; ...

2017-08-07

Understanding the science of plasma-material interactions (PMI) is essential for the future development of fusion facilities. The design of divertors and first walls for the next generation of long-pulse fusion facilities, such as a Fusion Nuclear Science Facility (FNSF) or a DEMO, requires significant PMI research and development. In order to meet this need, a new linear plasma facility, the Materials Plasma Exposure Experiment (MPEX) is proposed, which will produce divertor relevant plasma conditions for these next generation facilities. The device will be capable of handling low activation irradiated samples and be able to remove and replace samples without breakingmore » vacuum. A Target Exchange Chamber (TEC) which can be disconnected from the high field environment in order to perform in-situ diagnostics is planned for the facility as well. The vacuum system for MPEX must be carefully designed in order to meet the requirements of the different heating systems, and to provide conditions at the target similar to those expected in a divertor. An automated coupling-decoupling (“autocoupler”) system is designed to create a high vacuum seal, and will allow the TEC to be disconnected without breaking vacuum in either the TEC or the primary plasma materials interaction chamber. This autocoupler, which can be actuated remotely in the presence of the high magnetic fields, has been designed and prototyped, and shows robustness in a variety of conditions. The vacuum system has been modeled using a simplified finite element analysis, and indicates that the design goals for the pressures in key regions of the facility are achievable.« less

Steady-State Vacuum Ultraviolet Exposure Facility With Automated Lamp Calibration and Sample Positioning Fabricated

NASA Technical Reports Server (NTRS)

Sechkar, Edward A.; Steuber, Thomas J.; Banks, Bruce A.; Dever, Joyce A.

2000-01-01

The Next Generation Space Telescope (NGST) will be placed in an orbit that will subject it to constant solar radiation during its planned 10-year mission. A sunshield will be necessary to passively cool the telescope, protecting it from the Sun s energy and assuring proper operating temperatures for the telescope s instruments. This sunshield will be composed of metalized polymer multilayer insulation with an outer polymer membrane (12 to 25 mm in thickness) that will be metalized on the back to assure maximum reflectance of sunlight. The sunshield must maintain mechanical integrity and optical properties for the full 10 years. This durability requirement is most challenging for the outermost, constantly solar-facing polymer membrane of the sunshield. One of the potential threats to the membrane material s durability is from vacuum ultraviolet (VUV) radiation in wavelengths below 200 nm. Such radiation can be absorbed in the bulk of these thin polymer membrane materials and degrade the polymer s optical and mechanical properties. So that a suitable membrane material can be selected that demonstrates durability to solar VUV radiation, ground-based testing of candidate materials must be conducted to simulate the total 10- year VUV exposure expected during the Next Generation Space Telescope mission. The Steady State Vacuum Ultraviolet exposure facility was designed and fabricated at the NASA Glenn Research Center at Lewis Field to provide unattended 24-hr exposure of candidate materials to VUV radiation of 3 to 5 times the Sun s intensity in the wavelength range of 115 to 200 nm. The facility s chamber, which maintains a pressure of approximately 5 10(exp -6) torr, is divided into three individual exposure cells, each with a separate VUV source and sample-positioning mechanism. The three test cells are separated by a water-cooled copper shield plate assembly to minimize thermal effects from adjacent test cells. Part of the interior sample positioning mechanism of one

ART Attrition across Health Facilities Implementing Option B+ in Haiti.

PubMed

Myrtil, Martine Pamphile; Puttkammer, Nancy; Gloyd, Stephen; Robinson, Julia; Yuhas, Krista; Domercant, Jean Wysler; Honoré, Jean Guy; Francois, Kesner

2018-01-01

Describing factors related to high attrition is important in order to improve the implementation of the Option B+ strategy in Haiti. We conducted a retrospective cohort study to describe the variability of antiretroviral therapy (ART) retention across health facilities among pregnant and lactating women and assess for differences in ART retention between Option B+ clients and other ART patients. There were 1989 Option B+ clients who initiated ART in 45 health facilities. The percentage of attrition varied from 9% to 81% across the facilities. The largest health facilities had 38% higher risk of attrition (relative risk [RR]: 1.38, 95% confidence interval [CI]: 1.08-1.77, P = .009). Private institutions had 18% less risk of attrition (RR: 0.82, 95% CI: 0.70-0.96, P = .020). Health facilities located in the West department and the South region had lower risk of attrition. Being on treatment in a large or public health facility or a facility located in the North region was a significant risk factor associated with high attrition among Option B+ clients. The implementation of the Option B+ strategy must be reevaluated in order to effectively eliminate mother-to-child HIV transmission.

Supplemental multilayer insulation research facility

NASA Technical Reports Server (NTRS)

Dempsey, P. J.; Stochl, R. J.

1995-01-01

The Supplemental Multilayer Insulation Research Facility (SMIRF) provides a small scale test bed for conducting cryogenic experiments in a vacuum environment. The facility vacuum system is capable of simulating a Space Shuttle launch pressure profile as well as providing a steady space vacuum environment of 1.3 x 10(exp -4) Newton/sq meter (1 x 10(exp -6) torr). Warm side boundary temperatures can be maintained constant between 111 K (200 R) and 361 K (650 R) using a temperature controlled shroud. The shroud can also simulate a typical lunar day-night temperature profile. The test hardware consists of a cryogenic calorimeter supported by the lid of the vacuum chamber. A 0.45 cu meter (120 gallon) vacuum jacketed storage/supply tank is available for conditioning the cryogen prior to use in the calorimeter. The facility was initially designed to evaluate the thermal performance of insulation systems for long-term storage in space. The facility has recently been used to evaluate the performance of various new insulation systems for LH2 and LN2 ground storage dewars.

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...

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...

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...

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...

Test facility requirements for the thermal vacuum thermal balance test of the Cosmic Background Explorer Observatory

NASA Technical Reports Server (NTRS)

Milam, Laura J.

1991-01-01

The Cosmic Background Explorer Observatory (COBE) underwant a thermal vacuum thermal balance test in the Space Environment Simulator (SES). This was the largest and most complex test ever conducted at this facility. The 4 x 4 m (13 x 13 ft) spacecraft weighed approx. 2223 kg (4900 lbs) for the test. The test set up included simulator panels for the inboard solar array panels, simulator panels for the flight cowlings, Sun and Earth Sensor stimuli, Thermal Radio Frequency Shield heater stimuli and a cryopanel for thermal control in the Attitude Control System Shunt Dissipator area. The fixturing also included a unique 4.3 m (14 ft) diameter Gaseous Helium Cryopanel which provided a 20 K environment for the calibration of one of the spacecraft's instruments, the Differential Microwave Radiometer. This cryogenic panel caused extra contamination concerns and a special method was developed and written into the test procedure to prevent the high buildup of condensibles on the panel which could have led to backstreaming of the thermal vacuum chamber. The test was completed with a high quality simulated space environment provided to the spacecraft. The test requirements, test set up, and special fixturing are described.

13. VIEW OF VACUUM CHAMBER AND WELDING EQUIPMENT IN MODULE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. VIEW OF VACUUM CHAMBER AND WELDING EQUIPMENT IN MODULE E. PARTS WERE WELDED UNDER A VACUUM TO PREVENT CORROSION. (11/6/73) - Rocky Flats Plant, Plutonium Manufacturing Facility, North-central section of Plant, just south of Building 776/777, Golden, Jefferson County, CO

7 CFR 15b.38 - Health care facilities.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 1 2012-01-01 2012-01-01 false Health care facilities. 15b.38 Section 15b.38... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Other Aid, Benefits, or Services § 15b.38 Health care... impaired. A recipient hospital that provides health services or benefits shall establish a procedure for...

7 CFR 15b.38 - Health care facilities.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Health care facilities. 15b.38 Section 15b.38... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Other Aid, Benefits, or Services § 15b.38 Health care... impaired. A recipient hospital that provides health services or benefits shall establish a procedure for...

7 CFR 15b.38 - Health care facilities.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 1 2011-01-01 2011-01-01 false Health care facilities. 15b.38 Section 15b.38... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Other Aid, Benefits, or Services § 15b.38 Health care... impaired. A recipient hospital that provides health services or benefits shall establish a procedure for...

7 CFR 15b.38 - Health care facilities.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 1 2013-01-01 2013-01-01 false Health care facilities. 15b.38 Section 15b.38... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Other Aid, Benefits, or Services § 15b.38 Health care... impaired. A recipient hospital that provides health services or benefits shall establish a procedure for...

48 CFR 47.303-2 - F.o.b. origin, contractor's facility.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false F.o.b. origin, contractor... REGULATION CONTRACT MANAGEMENT TRANSPORTATION Transportation in Supply Contracts 47.303-2 F.o.b. origin, contractor's facility. (a) Explanation of delivery term. F.o.b. origin, contractor's facility means free of...

Assessing the prospects for achieving double-shell ignition on the National Ignition Facility using vacuum hohlraums

NASA Astrophysics Data System (ADS)

Amendt, Peter

2006-10-01

The goal of demonstrating ignition on the National Ignition Facility (NIF) has motivated a revisit of double-shell (DS) [1] targets as a complementary path to the baseline cryogenic single-shell approach [2]. Benefits of DS targets include room-temperature deuterium-tritium (DT) fuel preparation, minimal hohlraum-plasma-mediated laser backscatter, low threshold-ignition temperatures (4 keV) for relaxed hohlraum x-ray flux asymmetry tolerances [3], and loose shock timing requirements. On the other hand, DS ignition presents several challenges, including room-temperature containment of high-pressure DT (790 atm) in the inner shell; strict concentricity requirements on the two shells; development of nanoporous, low-density, metallic foams for structural support of the inner shell and hydrodynamic instability mitigation; and effective control of perturbation growth on the high-Atwood number interface between the DT fuel and the high-Z inner shell. Recent progress in DS ignition target designs using vacuum hohlraums is described, offering the potential for low levels of laser backscatter from stimulated Raman and Brillouin processes. In addition, vacuum hohlraums have the operational advantages of room temperature fielding and fabrication simplicity, as well as benefiting from extensive benchmarking on the Nova and Omega laser facilities. As an alternative to standard cylindrical hohlraums, a rugby-shaped geometry is also introduced that may provide energetics and symmetry tuning benefits for more robust DS designs with yields exceeding 10 MJ for 2 MJ of 3w laser energy. The recent progress in hohlraum designs and required advanced materials development are scheduled to culminate in a prototype demonstration of a NIF-scale ignition-ready DS in 2007. [1] P. Amendt et al., PoP 9, 2221 (2002). [2] J.D. Lindl et al., PoP 11, 339 (2004). [3] M.N. Chizhkov et al., Laser Part. Beams 23, 261 (2005). In collaboration with C. Cerjan, A. Hamza, J. Milovich and H. Robey.

14. VIEW OF VACUUM COATING CHAMBER. THE SYSTEM USED TITANIUM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. VIEW OF VACUUM COATING CHAMBER. THE SYSTEM USED TITANIUM VAPORS TO DEPOSIT TITANIUM COATING ONTO URANIUM PARTS UNDER A VACUUM. (1/11/83) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

Indian Vacuum Society: The Indian Vacuum Society

NASA Astrophysics Data System (ADS)

Saha, T. K.

2008-03-01

has instituted the `IVS- Professor D Y Phadke Memorial Prize' in memory of our founder president, the late Professor D Y Phadke at the University of Mumbai. The prize is given every year to the student ranked top in the MSc (PHY.) examination conducted by the university. The IVS Kolkata Chapter has established the Dr A S Divatia Memorial Trust with the objective of organizing the Dr A S Divatia Memorial Lecture and a seminar once a year and to set up a vacuum testing and calibration facility. IVS has instituted an award in memory of the late Shri C Ambasankaran, its past president and pioneer of vacuum technology in India. This award is given to one of the best papers presented in the national symposium conducted by IVS. One more best paper award `Smt. Shakuntalabai Vyawahare Memorial Prize' is established from a donation given by Shri Mohan R Vyawahare, a life member and a present EC member of the society, in memory of his mother. During the symposia, IVS felicitates two of its members, one from Industry and one from an R & D Institution for their lifetime contribution to vacuum science and technology. Dr A K Gupta, Ex BARC, Ex Generla Manager, IBP, Head, Energy Group, Shapoorji Pallonji & Co Ltd (Industry), and Dr S R Gowariker, Ex BARC, Ex Director, CSIO, Chandigarh, Director, Tolani Education Foundation (R & D) are being honoured this year. T K Saha Geneneral Secretary, IVS

REQUIREMENTS AND GUIDELINES FOR NSLS EXPERIMENTAL BEAM LINE VACUUM SYSTEMS-REVISION B.

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

FOERSTER,C.

Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas aftermore » a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are used at various beam line locations so that the monochromator, mirror box or sample chamber may be used in a helium atmosphere or rough vacuum. The window separates ring vacuum from the environment of the downstream beam line components. The stored beam lifetime in the storage rings and the maintenance of desirable reflection properties of optical surfaces depend upon hydrocarbon-free, ultra-high vacuum systems. Storage ring vacuum systems will operate at pressures of {approximately} 1 x 10{sup {minus}10} Torr without beam and {approximately} 1 x 10{sup {minus}9} Torr with beam. Systems are free of hydrocarbons in the sense that no pumps, valves, etc. containing organics are used. Components are all-metal, chemically cleaned and bakeable. To the extent that beam lines share a common vacuum with the storage ring, the same criteria will hold for beam line components. The design philosophy for NSLS beam lines is to use all-metal, hydrocarbon-free front end components and recommend that experimenters use this approach for common vacuum hardware downstream

The test facility requirements for the thermal vacuum thermal balance test of the Cosmic Background Explorer Observatory

NASA Technical Reports Server (NTRS)

Milam, Laura J.

1990-01-01

The Cosmic Background Explorer Observatory (COBE) underwent a thermal vacuum thermal balance test in the Space Environment Simulator (SES). This was the largest and most complex test ever conducted at this facility. The 4 x 4 m (13 x 13 ft) spacecraft weighed approx. 2223 kg (4900 lbs) for the test. The test set up included simulator panels for the inboard solar array panels, simulator panels for the flight cowlings, Sun and Earth Sensor stimuli, Thermal Radio Frequency Shield heater stimuli and a cryopanel for thermal control in the Attitude Control System Shunt Dissipator area. The fixturing also included a unique 4.3 m (14 ft) diameter Gaseous Helium Cryopanel which provided a 20 K environment for the calibration of one of the spacecraft's instruments, the Differential Microwave Radiometer. This cryogenic panel caused extra contamination concerns and a special method was developed and written into the test procedure to prevent the high buildup of condensibles on the panel which could have led to backstreaming of the thermal vacuum chamber. The test was completed with a high quality simulated space environment provided to the spacecraft. The test requirements, test set up, and special fixturing are described.

48 CFR 52.247-30 - F.o.b. Origin, Contractor's Facility.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false F.o.b. Origin, Contractor... Clauses 52.247-30 F.o.b. Origin, Contractor's Facility. As prescribed in 47.303-2(c), insert the following clause in solicitations and contracts when the delivery term is f.o.b. origin, contractor's facility: F.o...

A proposed search for dark-matter axions in the 0.6-16 micro-eV range

NASA Technical Reports Server (NTRS)

Vanbibber, Karl; Sikivie, P.; Sullivan, N. S.; Tanner, D. B.; Turner, Michael S.; Moltz, D. M.

1991-01-01

A proposed experiment is described to search for dark matter axions in the mass range 0.6 to 16 micro-eV. The method is based on the Primakoff conversion of axions into monochromatic microwave photons inside a tunable microwave cavity in a large volume high field magnet, as described by Sikivie. This proposal capitalizes on the availability of two Axicell magnets from the decommissioned Mirror Fusion Test Facility (MFTF-B) fusion machine at LLNL. Assuming a local dark matter density in axions of rho = 0.3 GeV/cu cm, the axion would be found or ruled out at the 97 pct. c.l. in the above mass range in 48 months.

The Effect of Temperature on the Survival of Microorganisms in a Deep Space Vacuum

NASA Technical Reports Server (NTRS)

Hagen, C. A.; Godfrey, J. F.; Green, R. H.

1971-01-01

A space molecular sink research facility (Molsink) was used to evaluate the ability of microorganisms to survive the vacuum of outer space. This facility could be programmed to simulate flight spacecraft vacuum environments at pressures in the .1 nanotorr range and thermal gradients (30 to 60 C) closely associated to surface temperatures of inflight spacecraft. Initial populations of Staphylococcus epidermidis and a Micrococcus sp. were reduced approximately 1 log while exposed to -105 and 34 C, and approximately 2 logs while exposed to 59 C for 14 days in the vacuum environment. Spores of Bacillus subtilis var. niger were less affected by the environment. Initial spore populations were reduced 0.2, 0.3, and 0.8 log during the 14-day vacuum exposure at -124, 34, and 59 C, respectively.

Facile generation of cell microarrays using vacuum degassing and coverslip sweeping.

PubMed

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.

Compactified Vacuum in Ten Dimensions.

NASA Astrophysics Data System (ADS)

Wurmser, Daniel

1987-09-01

Since the 1920's, theories which unify gravity with the other fundamental forces have called for more than the four observed dimensions of space-time. According to such a theory, the vacuum consists of flat four-dimensional space-time described by the Minkowski metric M ^4 and a "compactified" space B. The dimensions of B are small, and the space can only be observed at distance scales smaller than the present experimental limit. These theories have had serious difficulties. The equations of gravity severely restrict the possible choices for the space B. The allowed spaces are complicated and difficult to study. The vacuum is furthermore unstable in the sense that a small perturbation causes the compactified dimensions to expand indefinitely. There is an addition a semi-classical argument which implies that the compactified vacuum be annihilated by virtual black holes. It follows that a universe with compactified extra dimensions could not have survived to the present. These results were derived by applying the equations of general relativity to spaces of more than four dimensions. The form of these equations was assumed to be unchanged by an increase in the number of dimensions. Recently, it has been proposed that gravity in more than four dimensions may involve terms of higher order in the curvature as well as the linear terms present in ordinary general relativity. I illustrate the effect of such terms by considering the example B = S^6 where S ^6 is the six-dimensional sphere. Only when the extra terms are included is this choice of the compactified space allowed. I explore the effect of a small perturbation on such a vacuum. The ten-dimensional spherically symmetric potential is examined, and I determine conditions under which the formation of virtual black holes is forbidden. The example M^4 times S^6 is still plagued by the semi -classical instability, but this result does not hold in general. The requirement that virtual black holes be forbidden provides a

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.

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.

7 CFR 15b.18 - Existing facilities.

Code of Federal Regulations, 2010 CFR

2010-01-01

... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Accessibility § 15b.18 Existing facilities. (a) Accessibility. A recipient shall operate each assisted program or activity so that when each part is viewed in... results in making its program or activity accessible to qualified handicapped persons. A recipient is not...

Vacuum Chamber Documentation for U of H Collection

NASA Image and Video Library

2006-06-16

Documentation for the University of Houston (UH) Clear Lake collection of their library books after the Vacuum Chamber runs were performed to remove the water from them. Vacuum Chamber B in Building 32 was used.

Vacuum statistics and stability in axionic landscapes

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

Masoumi, Ali; Vilenkin, Alexander, E-mail: ali@cosmos.phy.tufts.edu, E-mail: vilenkin@cosmos.phy.tufts.edu

2016-03-01

We investigate vacuum statistics and stability in random axionic landscapes. For this purpose we developed an algorithm for a quick evaluation of the tunneling action, which in most cases is accurate within 10%. We find that stability of a vacuum is strongly correlated with its energy density, with lifetime rapidly growing as the energy density is decreased. On the other hand, the probability P(B) for a vacuum to have a tunneling action B greater than a given value declines as a slow power law in B. This is in sharp contrast with the studies of random quartic potentials, which foundmore » a fast exponential decline of P(B). Our results suggest that the total number of relatively stable vacua (say, with B>100) grows exponentially with the number of fields N and can get extremely large for N∼> 100. The problem with this kind of model is that the stable vacua are concentrated near the absolute minimum of the potential, so the observed value of the cosmological constant cannot be explained without fine-tuning. To address this difficulty, we consider a modification of the model, where the axions acquire a quadratic mass term, due to their mixing with 4-form fields. This results in a larger landscape with a much broader distribution of vacuum energies. The number of relatively stable vacua in such models can still be extremely large.« less

The Berkeley extreme ultraviolet calibration facility

NASA Technical Reports Server (NTRS)

Welsh, Barry Y.; Jelinsky, Patrick; Malina, Roger F.

1988-01-01

The vacuum calibration facilities of the Space Sciences Laboratory, University of California at Berkeley are designed for the calibration and testing of EUV and FUV spaceborne instrumentation (spectral range 44-2500 A). The facility includes one large cylindrical vacuum chamber (3 x 5 m) containing two EUV collimators, and it is equipped with a 4-axis manipulator of angular-control resolution 1 arcsec for payloads weighing up to 500 kg. In addition, two smaller cylindrical chambers, each 0.9 x 1.2 m, are available for vacuum and thermal testing of UV detectors, filters, and space electronics hardware. All three chambers open into class-10,000 clean rooms, and all calibrations are referred to NBS secondary standards.

SLUDGE TREATMENT PROJECT KOP DISPOSITION - THERMAL AND GAS ANALYSIS FOR THE COLD VACUUM DRYING FACILITY

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

SWENSON JA; CROWE RD; APTHORPE R

2010-03-09

The purpose of this document is to present conceptual design phase thermal process calculations that support the process design and process safety basis for the cold vacuum drying of K Basin KOP material. This document is intended to demonstrate that the conceptual approach: (1) Represents a workable process design that is suitable for development in preliminary design; and (2) Will support formal safety documentation to be prepared during the definitive design phase to establish an acceptable safety basis. The Sludge Treatment Project (STP) is responsible for the disposition of Knock Out Pot (KOP) sludge within the 105-K West (KW) Basin.more » KOP sludge consists of size segregated material (primarily canister particulate) from the fuel and scrap cleaning process used in the Spent Nuclear Fuel process at K Basin. The KOP sludge will be pre-treated to remove fines and some of the constituents containing chemically bound water, after which it is referred to as KOP material. The KOP material will then be loaded into a Multi-Canister Overpack (MCO), dried at the Cold Vacuum Drying Facility (CVDF) and stored in the Canister Storage Building (CSB). This process is patterned after the successful drying of 2100 metric tons of spent fuel, and uses the same facilities and much of the same equipment that was used for drying fuel and scrap. Table ES-l present similarities and differences between KOP material and fuel and between MCOs loaded with these materials. The potential content of bound water bearing constituents limits the mass ofKOP material in an MCO load to a fraction of that in an MCO containing fuel and scrap; however, the small particle size of the KOP material causes the surface area to be significantly higher. This relatively large reactive surface area represents an input to the KOP thermal calculations that is significantly different from the calculations for fuel MCOs. The conceptual design provides for a copper insert block that limits the volume

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.

National Synchrotron Light Source II storage ring vacuum systems

DOE PAGES

Hseuh, Hsiao-Chaun; Hetzel, Charles; Leng, Shuwei; ...

2016-04-05

The National Synchrotron Light Source II, completed in 2014, is a 3-GeV synchrotron radiation (SR) facility at Brookhaven National Laboratory and has been in steady operation since. With a design electron current of 500 mA and subnanometer radians horizontal emittance, this 792-m circumference storage ring is providing the highest flux and brightness x-ray beam for SR users. Also, the majority of the storage ring vacuum chambers are made of extruded aluminium. Chamber sections are interconnected using low-impedance radiofrequency shielded bellows. SR from the bending magnets is intercepted by water-cooled compact photon absorbers resided in the storage ring chambers. Finally, thismore » paper presents the design of the storage ring vacuum system, the fabrication of vacuum chambers and other hardware, the installation, the commissioning, and the continuing beam conditioning of the vacuum systems.« less

National Synchrotron Light Source II storage ring vacuum systems

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

Hseuh, Hsiao-Chaun, E-mail: hseuh@bnl.gov; Hetzel, Charles; Leng, Shuwei

2016-05-15

The National Synchrotron Light Source II, completed in 2014, is a 3-GeV synchrotron radiation (SR) facility at Brookhaven National Laboratory and has been in steady operation since. With a design electron current of 500 mA and subnanometer radians horizontal emittance, this 792-m circumference storage ring is providing the highest flux and brightness x-ray beam for SR users. The majority of the storage ring vacuum chambers are made of extruded aluminium. Chamber sections are interconnected using low-impedance radiofrequency shielded bellows. SR from the bending magnets is intercepted by water-cooled compact photon absorbers resided in the storage ring chambers. This paper presents themore » design of the storage ring vacuum system, the fabrication of vacuum chambers and other hardware, the installation, the commissioning, and the continuing beam conditioning of the vacuum systems.« less

10 CFR 140.13b - Amount of liability insurance required for uranium enrichment facilities.

Code of Federal Regulations, 2010 CFR

2010-01-01

... enrichment facilities. 140.13b Section 140.13b Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) FINANCIAL... required for uranium enrichment facilities. Each holder of a license issued under Parts 40 or 70 of this chapter for a uranium enrichment facility that involves the use of source material or special nuclear...

Vacuum Processing Technique for Development of Primary Standard Blackbodies

PubMed Central

Navarro, M.; Bruce, S. S.; Johnson, B. Carol; Murthy, A. V.; Saunders, R. D.

1999-01-01

Blackbody sources with nearly unity emittance that are in equilibrium with a pure freezing metal such as gold, silver, or copper are used as primary standard sources in the International Temperature Scale of 1990 (ITS-90). Recently, a facility using radio-frequency induction heating for melting and filling the blackbody crucible with the freeze metal under vacuum conditions was developed at the National Institute of Standards and Technology (NIST). The blackbody development under a vacuum environment eliminated the possibility of contamination of the freeze metal during the process. The induction heating, compared to a resistively heated convection oven, provided faster heating of crucible and resulted in shorter turn-around time of about 7 h to manufacture a blackbody. This paper describes the new facility and its application to the development of fixed-point blackbodies.

Vehicle-Level Oxygen/Methane Propulsion System Hotfire Testing at Thermal Vacuum Conditions

NASA Technical Reports Server (NTRS)

Morehead, Robert L.; Melcher, J. C.; Atwell, Matthew J.; Hurlbert, Eric A.; Desai, Pooja; Werlink, Rudy

2017-01-01

A prototype integrated liquid oxygen/liquid methane propulsion system was hot-fire tested at a variety of simulated altitude and thermal conditions in the NASA Glenn Research Center Plum Brook Station In-Space Propulsion Thermal Vacuum Chamber (formerly B2). This test campaign served two purposes: 1) Characterize the performance of the Plum Brook facility in vacuum accumulator mode and 2) Collect the unique data set of an integrated LOX/Methane propulsion system operating in high altitude and thermal vacuum environments (a first). Data from this propulsion system prototype could inform the design of future spacecraft in-space propulsion systems, including landers. The test vehicle for this campaign was the Integrated Cryogenic Propulsion Test Article (ICPTA), which was constructed for this project using assets from the former Morpheus Project rebuilt and outfitted with additional new hardware. The ICPTA utilizes one 2,800 lbf main engine, two 28 lbf and two 7 lbf reaction control engines mounted in two pods, four 48-inch propellant tanks (two each for liquid oxygen and liquid methane), and a cold helium system for propellant tank pressurization. Several hundred sensors on the ICPTA and many more in the test cell collected data to characterize the operation of the vehicle and facility. Multiple notable experiments were performed during this test campaign, many for the first time, including pressure-fed cryogenic reaction control system characterization over a wide range of conditions, coil-on-plug ignition system demonstration at the vehicle level, integrated main engine/RCS operation, and a non-intrusive propellant mass gauging system. The test data includes water-hammer and thermal heat leak data critical to validating models for use in future vehicle design activities. This successful test campaign demonstrated the performance of the updated Plum Brook In-Space Propulsion thermal vacuum chamber and incrementally advanced the state of LOX/Methane propulsion

Phase equilibrium in system Ti-Si-C-B and synthesis of MAX phase layers in vacuum under the influence of electron beam

NASA Astrophysics Data System (ADS)

Smirnyagina, N. N.; Khaltanova, V. M.; Dasheev, D. E.; Lapina, A. E.

2017-05-01

Composite layers on the basis of carbides and borides the titan and silicon on titanic alloy VТ-1 are generated at diffused saturation by electron beam treatment in vacuum. Formation in a composite of MAX phase Ti3SiC2 is shown. Thermodynamic research of phase equilibrium in systems Ti-Si-C and Ti-B-C in the conditions of high vacuum is executed. The thermodynamics, formation mechanisms of superfirm layers borides and carbides of the titan and silicon are investigated.

Use of space ultra-vacuum for high quality semiconductor thin film growth

NASA Technical Reports Server (NTRS)

Ignatiev, A.; Sterling, M.; Sega, R. M.

1992-01-01

The utilization of space for materials processing is being expanded through a unique concept of epitaxial thin film growth in the ultra-vacuum of low earth orbit (LEO). This condition can be created in the wake of an orbiting space vehicle; and assuming that the vehicle itself does not pertub the environment, vacuum levels of better than 10 exp -14 torr can be attained. This vacuum environment has the capacity of greatly enhancing epitaxial thin film growth and will be the focus of experiments conducted aboard the Wake Shield Facility (WSF) currently being developed by the Space Vacuum Epitaxy Center (SVEC), Industry, and NASA.

Atomic Oxygen Lamp Cleaning Facility Fabricated and Tested

NASA Technical Reports Server (NTRS)

Sechkar, Edward A.; Stueber, Thomas J.

1999-01-01

NASA Lewis Research Center's Atomic Oxygen Lamp Cleaning Facility was designed to produce an atomic oxygen plasma within a metal halide lamp to remove carbon-based contamination. It is believed that these contaminants contribute to the high failure rate realized during the production of these lamps. The facility is designed to evacuate a metal halide lamp and produce a radio frequency generated atomic oxygen plasma within it. Oxygen gas, with a purity of 0.9999 percent and in the pressure range of 150 to 250 mtorr, is used in the lamp for plasma generation while the lamp is being cleaned. After cleaning is complete, the lamp can be backfilled with 0.9999-percent pure nitrogen and torch sealed. The facility comprises various vacuum components connected to a radiation-shielded box that encloses the bulb during operation. Radiofrequency power is applied to the two parallel plates of a capacitor, which are on either side of the lamp. The vacuum pump used, a Leybold Trivac Type D4B, has a pumping speed of 4-m3/hr, has an ultimate pressure of <8x10-4, and is specially adapted for pure oxygen service. The electronic power supply, matching network, and controller (500-W, 13.56-MHz) used to supply the radiofrequency power were purchased from RF Power Products Inc. Initial test results revealed that this facility could remove the carbon-based contamination from within bulbs.

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

Requirements Doc for Refurb of JASPER Facility in B131HB

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

Knittel, Kenn M.

The Joint Actinide Shock Physics Experimental Research (JASPER) Program target fabrication facility is currently located in building 131 (B131) of the Lawrence Livermore National Laboratory (LLNL). A portion of this current facility has been committed to another program as part of a larger effort to consolidate LLNL capabilities into newer facilities. This facility assembles precision targets for scientific studies at the Nevada National Security Site (NNSS). B131 is also going through a modernization project to upgrade the infrastructure and abate asbestos. These activities will interrupt the continuous target fabrication efforts for the JASPER Program. Several options are explored to meetmore » the above conflicting requirements, with the final recommendation to prepare a new facility for JASPER target fabrication operations before modernization efforts begin in the current facility assigned to JASPER. This recommendation fits within all schedule constraints and minimizes the disruption to the JASPER Program. This option is not without risk, as it requires moving an aged, precision coordinate measuring machine, which is essential to the JASPER Program’s success. The selected option balances the risk to the machine with continuity of operations.« less

Vacuum Ultraviolet (VUV) radiation-induced degradation of Fluorinated Ethylene Propylene (FEP) Teflon aboard the Long Duration Exposure Facility (LDEF)

NASA Technical Reports Server (NTRS)

Brinza, David E.; Stiegman, A. E.; Staszak, Paul R.; Laue, Eric G.; Liang, Ranty H.

1992-01-01

Examination of fluorinated ethylene propylene (FEP) copolymer specimens recovered from the Long Duration Exposure Facility (LDEF) provides evidence for degradation attributed to extended solar vacuum ultraviolet (VUV) irradiation. Scanning electron microscope (SEM) images of sheared FEP film edges reveal the presence of a highly embrittled layer on the exposed surface of specimens obtained from the trailing edge of the LDEF. Similar images obtained for leading edge and control FEP films do not exhibit evidence for such an embrittled layer. Laboratory VUV irradiation of FEP films is found to produce a damage layer similar to that witnessed in the LDEF trailing edge films. Spectroscopic analyses of irradiated films provide data to advance a photochemical mechanism for degradation.

Vacuum force

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).

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.

Skylab Shroud in the Space Power Facility

NASA Image and Video Library

1970-12-21

The 56-foot tall, 24,400-pound Skylab shroud installed in the Space Power Facility’s vacuum chamber at the National Aeronautics and Space Administration’s (NASA) Plum Brook Station. The Space Power Facility, which began operations in 1969, is the largest high vacuum chamber ever built. The chamber is 100 feet in diameter and 120 feet high. It can produce a vacuum deep enough to simulate the conditions at 300 miles altitude. The Space Power Facility was originally designed to test nuclear-power sources for spacecraft during long durations in a space atmosphere, but it was never used for that purpose. Payload shrouds are aerodynamic fairings to protect the payload during launch and ascent to orbit. The Skylab mission utilized the largest shroud ever attempted. Unlike previous launches, the shroud would not be jettisoned until the spacecraft reached orbit. NASA engineers designed these tests to verify the dynamics of the jettison motion in a simulated space environment. Fifty-four runs and three full-scale jettison tests were conducted from mid-September 1970 to June 1971. The shroud behaved as its designers intended, the detonators all fired, and early design issues were remedied by the final test. The Space Power Facility continues to operate today. The facility can sustain a high vacuum; simulate solar radiation via a 4-megawatt quartz heat lamp array, solar spectrum by a 400-kilowatt arc lamp, and cold environments. Test programs at the facility include high-energy experiments, shroud separation tests, Mars Lander system tests, deployable Solar Sail tests and International Space Station hardware tests.

40 CFR 60.110b - Applicability and designation of affected facility.

Code of Federal Regulations, 2010 CFR

2010-07-01

... an attachment to the notification required by 40 CFR 65.5(b). [52 FR 11429, Apr. 8, 1987, as amended... designation of affected facility. (a) Except as provided in paragraph (b) of this section, the affected..., reconstruction, or modification is commenced after July 23, 1984. (b) This subpart does not apply to storage...

40 CFR 60.110b - Applicability and designation of affected facility.

Code of Federal Regulations, 2013 CFR

2013-07-01

... an attachment to the notification required by 40 CFR 65.5(b). [52 FR 11429, Apr. 8, 1987, as amended... designation of affected facility. (a) Except as provided in paragraph (b) of this section, the affected..., reconstruction, or modification is commenced after July 23, 1984. (b) This subpart does not apply to storage...

40 CFR 60.110b - Applicability and designation of affected facility.

Code of Federal Regulations, 2012 CFR

2012-07-01

... an attachment to the notification required by 40 CFR 65.5(b). [52 FR 11429, Apr. 8, 1987, as amended... designation of affected facility. (a) Except as provided in paragraph (b) of this section, the affected..., reconstruction, or modification is commenced after July 23, 1984. (b) This subpart does not apply to storage...

40 CFR 60.110b - Applicability and designation of affected facility.

Code of Federal Regulations, 2011 CFR

2011-07-01

... an attachment to the notification required by 40 CFR 65.5(b). [52 FR 11429, Apr. 8, 1987, as amended... designation of affected facility. (a) Except as provided in paragraph (b) of this section, the affected..., reconstruction, or modification is commenced after July 23, 1984. (b) This subpart does not apply to storage...

40 CFR 60.110b - Applicability and designation of affected facility.

Code of Federal Regulations, 2014 CFR

2014-07-01

... an attachment to the notification required by 40 CFR 65.5(b). [52 FR 11429, Apr. 8, 1987, as amended... designation of affected facility. (a) Except as provided in paragraph (b) of this section, the affected..., reconstruction, or modification is commenced after July 23, 1984. (b) This subpart does not apply to storage...

Research regarding the vacuuming of liquid steel on steel degassing

NASA Astrophysics Data System (ADS)

Magaon, M.; Radu, M.; Şerban, S.; Zgripcea, L.

2018-01-01

When the liquid steel comes in contact with the atmosphere of the elaboration aggregates, a process of gas diffusion into the metal bath takes place on the one hand, and on the other hand a process that allows them to pass from the metal bath into the atmosphere. The meaning of these processes is determined by a number of factors as follows: the quality of raw and auxiliary materials (moisture content, oils, etc.), the boiling intensity, the evacuation duration, the properties of used slags, the values of the casting ladle processing parameters (bubbling, vacuuming, etc.). The research was carried out at an electrical steelwork, equipped with an electric arc furnace type EBT (Electric Bottom Tapping) capacity 100t, LF (Ladle-Furnace) and VD (Vacuum Degassing) facilities, establishing some correlations between the vacuuming parameters from the V.D.facility and the amounts of hydrogen and nitrogen removed from the metal bath, as well as their removal efficiency, were taken into consideration. The obtained data was processed in MATLAB calculation program, the established correlations form was presented both in analytical and graphical form. The validity of these correlations was verified in practice, being particularly useful in research.

Development of High vacuum facility for baking and cool down experiments for SST-1 Tokamak components

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.

High-Energy Vacuum Birefringence and Dichroism in an Ultrastrong Laser Field

NASA Astrophysics Data System (ADS)

Bragin, Sergey; Meuren, Sebastian; Keitel, Christoph H.; Di Piazza, Antonino

2017-12-01

A long-standing prediction of quantum electrodynamics, yet to be experimentally observed, is the interaction between real photons in vacuum. As a consequence of this interaction, the vacuum is expected to become birefringent and dichroic if a strong laser field polarizes its virtual particle-antiparticle dipoles. Here, we derive how a generally polarized probe photon beam is influenced by both vacuum birefringence and dichroism in a strong linearly polarized plane-wave laser field. Furthermore, we consider an experimental scheme to measure these effects in the nonperturbative high-energy regime, where the Euler-Heisenberg approximation breaks down. By employing circularly polarized high-energy probe photons, as opposed to the conventionally considered linearly polarized ones, the feasibility of quantitatively confirming the prediction of nonlinear QED for vacuum birefringence at the 5 σ confidence level on the time scale of a few days is demonstrated for upcoming 10 PW laser systems. Finally, dichroism and anomalous dispersion in vacuum are shown to be accessible at these facilities.

The Zwicky Transient Facility Camera

NASA Astrophysics Data System (ADS)

Dekany, Richard; Smith, Roger M.; Belicki, Justin; Delacroix, Alexandre; Duggan, Gina; Feeney, Michael; Hale, David; Kaye, Stephen; Milburn, Jennifer; Murphy, Patrick; Porter, Michael; Reiley, Daniel J.; Riddle, Reed L.; Rodriguez, Hector; Bellm, Eric C.

2016-08-01

The Zwicky Transient Facility Camera (ZTFC) is a key element of the ZTF Observing System, the integrated system of optoelectromechanical instrumentation tasked to acquire the wide-field, high-cadence time-domain astronomical data at the heart of the Zwicky Transient Facility. The ZTFC consists of a compact cryostat with large vacuum window protecting a mosaic of 16 large, wafer-scale science CCDs and 4 smaller guide/focus CCDs, a sophisticated vacuum interface board which carries data as electrical signals out of the cryostat, an electromechanical window frame for securing externally inserted optical filter selections, and associated cryo-thermal/vacuum system support elements. The ZTFC provides an instantaneous 47 deg2 field of view, limited by primary mirror vignetting in its Schmidt telescope prime focus configuration. We report here on the design and performance of the ZTF CCD camera cryostat and report results from extensive Joule-Thompson cryocooler tests that may be of broad interest to the instrumentation community.

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

FACILITY 802B, BEDROOM ADJACENT TO BATHROOM, VIEW FACING NORTH. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FACILITY 802B, BEDROOM ADJACENT TO BATHROOM, VIEW FACING NORTH. - Schofield Barracks Military Reservation, Bachelor Officers' Quarters Type, Between Grimes & Tidball Streets near Ayres Avenue, Wahiawa, Honolulu County, HI

Optimized photonic gauge of extreme high vacuum with Petawatt lasers

NASA Astrophysics Data System (ADS)

Paredes, Ángel; Novoa, David; Tommasini, Daniele; Mas, Héctor

2014-03-01

One of the latest proposed applications of ultra-intense laser pulses is their possible use to gauge extreme high vacuum by measuring the photon radiation resulting from nonlinear Thomson scattering within a vacuum tube. Here, we provide a complete analysis of the process, computing the expected rates and spectra, both for linear and circular polarizations of the laser pulses, taking into account the effect of the time envelope in a slowly varying envelope approximation. We also design a realistic experimental configuration allowing for the implementation of the idea and compute the corresponding geometric efficiencies. Finally, we develop an optimization procedure for this photonic gauge of extreme high vacuum at high repetition rate Petawatt and multi-Petawatt laser facilities, such as VEGA, JuSPARC and ELI.

FACILITY 802B, LIVING ROOM AND ENTRY, VIEW FACING EASTNORTHEAST. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FACILITY 802B, LIVING ROOM AND ENTRY, VIEW FACING EAST-NORTHEAST. - Schofield Barracks Military Reservation, Bachelor Officers' Quarters Type, Between Grimes & Tidball Streets near Ayres Avenue, Wahiawa, Honolulu County, HI

MINERVA: A facility to study Microstructure and INterface Evolution in Realtime under VAcuum

NASA Astrophysics Data System (ADS)

Nicklin, Chris; Martinez-Hardigree, Josue; Warne, Adam; Green, Stephen; Burt, Martin; Naylor, John; Dorman, Adam; Wicks, Dean; Din, Salahud; Riede, Moritz

2017-10-01

A sample environment to enable real-time X-ray scattering measurements to be recorded during the growth of materials by thermal evaporation in vacuum is presented. The in situ capabilities include studying microstructure development with time or during exposure to different environmental conditions, such as temperature and gas pressure. The chamber provides internal slits and a beam stop, to reduce the background scattering from the X-rays passing through the entrance and exit windows, together with highly controllable flux rates of the evaporants. Initial experiments demonstrate some of the possibilities by monitoring the growth of bathophenanthroline (BPhen), a common molecule used in organic solar cells and organic light emitting diodes, including the development of the microstructure with time and depth within the film. The results show how BPhen nanocrystal structures coarsen at room temperature under vacuum, highlighting the importance of using real time measurements to understand the as-deposited pristine film structure and its development with time. More generally, this sample environment is versatile and can be used for investigation of structure-property relationships in a wide range of vacuum deposited materials and their applications in, for example, optoelectronic devices and energy storage.

Capabilities, Design, Construction and Commissioning of New Vibration, Acoustic, and Electromagnetic Capabilities Added to the World's Largest Thermal Vacuum Chamber at NASA's Space Power Facility

NASA Technical Reports Server (NTRS)

Motil, Susan M.; Ludwiczak, Damian R.; Carek, Gerald A.; Sorge, Richard N.; Free, James M.; Cikanek, Harry A., III

2011-01-01

NASA s human space exploration plans developed under the Exploration System Architecture Studies in 2005 included a Crew Exploration Vehicle launched on an Ares I launch vehicle. The mass of the Crew Exploration Vehicle and trajectory of the Ares I coupled with the need to be able to abort across a large percentage of the trajectory generated unprecedented testing requirements. A future lunar lander added to projected test requirements. In 2006, the basic test plan for Orion was developed. It included several types of environment tests typical of spacecraft development programs. These included thermal-vacuum, electromagnetic interference, mechanical vibration, and acoustic tests. Because of the size of the vehicle and unprecedented acoustics, NASA conducted an extensive assessment of options for testing, and as result, chose to augment the Space Power Facility at NASA Plum Brook Station, of the John H. Glenn Research Center to provide the needed test capabilities. The augmentation included designing and building the World s highest mass capable vibration table, the highest power large acoustic chamber, and adaptation of the existing World s largest thermal vacuum chamber as a reverberant electromagnetic interference test chamber. These augmentations were accomplished from 2007 through early 2011. Acceptance testing began in Spring 2011 and will be completed in the Fall of 2011. This paper provides an overview of the capabilities, design, construction and acceptance of this extraordinary facility.

Title I, Part B, Institutionalized Facilities Program, Summer 1982. Annual Evaluation Report.

ERIC Educational Resources Information Center

New York City Board of Education, Brooklyn, NY. Office of Educational Evaluation.

This 1982 summer Title I, Part B, Institutionalized Facilities Program provided supplementary career instruction to 188 students residing in facilities for neglected and delinquent children and youth. This report briefly describes the program, providing information on methodology, physical setting, equipment, and supplies; population and class…

Coil-On-Plug Ignition for LOX/Methane Liquid Rocket Engines in Thermal Vacuum Environments

NASA Technical Reports Server (NTRS)

Melcher, John C.; Atwell, Matthew J.; Morehead, Robert L.; Hurlbert, Eric A.; Bugarin, Luz; Chaidez, Mariana

2017-01-01

A coil-on-plug ignition system has been developed and tested for Liquid Oxygen (LOX) / liquid methane rocket engines operating in thermal vacuum conditions. The igniters were developed and tested as part of the Integrated Cryogenic Propulsion Test Article (ICPTA), previously tested as part of the Project Morpheus test vehicle. The ICPTA uses an integrated, pressure-fed, cryogenic LOX/methane propulsion system including a reaction control system (RCS) and a main engine. The ICPTA was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. In order to successfully demonstrate ignition reliability in the vacuum conditions and eliminate corona discharge issues, a coil-on-plug ignition system has been developed. The ICPTA uses spark-plug ignition for both the main engine igniter and the RCS. The coil-on-plug configuration eliminates the conventional high-voltage spark plug cable by combining the coil and the spark-plug into a single component. Prior to ICPTA testing at Plum Brook, component-level reaction control engine (RCE) and main engine igniter testing was conducted at NASA Johnson Space Center (JSC), which demonstrated successful hot-fire ignition using the coil-on-plug from sea-level ambient conditions down to 10(exp.-2) torr. Integrated vehicle hot-fire testing at JSC demonstrated electrical and command/data system performance. Lastly, Plum Brook testing demonstrated successful ignitions at simulated altitude conditions at 30 torr and cold thermal-vacuum conditions at 6 torr. The test campaign successfully proved that coil-on-plug technology will enable integrated LOX/methane propulsion systems in future spacecraft.

FACILITY 810, CORNER ENTRY TO UNIT B, OBLIQUE VIEW FACING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FACILITY 810, CORNER ENTRY TO UNIT B, OBLIQUE VIEW FACING SOUTH-SOUTHWEST. - Schofield Barracks Military Reservation, Duplex Housing Type with Corner Entries, Between Hamilton & Tidball Streets near Williston Avenue, Wahiawa, Honolulu County, HI

Leak rate measurements for satellite subsystems and residual gas analysis during space environment tests. [thermal vacuum and solar simulation tests

NASA Technical Reports Server (NTRS)

Nuss, H. E.

1975-01-01

The measuring and evaluation procedure for the determination of leak rates of satellite subsystems with a quadrupole mass spectrometer, and the results of the residual gas analysis are described. The method selected for leak rate determination was placing the system into a vacuum chamber and furnishing the chamber with a mass spectrometer and calibrated leaks. The residual gas of a thermal vacuum test facility, in which the thermal balance test radiation input was simulated by a heated canister, was analyzed with the mass spectrometer in the atomic mass unit range up to 300 amu. In addition to the measurements during the space environment tests, mass spectrometric studies were performed with samples of spacecraft materials. The studies were carried out during tests for the projects HELIOS, AEROS B and SYMPHONIE.

Reconfiguration of NASA GRC's Vacuum Facility 6 for Testing of Advanced Electric Propulsion System (AEPS) Hardware

NASA Technical Reports Server (NTRS)

Peterson, Peter; Kamhawi, Hani; Huang, Wensheng; Yim, John; Haag, Tom; Mackey, Jonathan; McVetta, Mike; Sorrelle, Luke; Tomsik, Tom; Gilligan, Ryan;

Reconfiguration of NASA GRC's Vacuum Facility 6 for Testing of Advanced Electric Propulsion System (AEPS) Hardware

NASA Technical Reports Server (NTRS)

Peterson, Peter Y.; Kamhawi, Hani; Huang, Wensheng; Yim, John; Haag, Tom; Mackey, Jonathan; McVetta, Mike; Sorrelle, Luke; Tomsik, Tom; Gilligan, Ryan;

Reconfiguration of NASA GRC's Vacuum Facility 6 for Testing of Advanced Electric Propulsion System (AEPS) Hardware

NASA Technical Reports Server (NTRS)

Peterson, Peter Y.; Kamhawi, Hani; Huang, Wensheng; Yim, John T.; Haag, Thomas W.; Mackey, Jonathan A.; McVetta, Michael S.; Sorrelle, Luke T.; Tomsik, Thomas M.; Gilligan, Ryan P.;

Recovery of materials from waste printed circuit boards by vacuum pyrolysis and vacuum centrifugal separation.

PubMed

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.

Enhanced Photocatalytic Activity of Vacuum-activated TiO2 Induced by Oxygen Vacancies.

PubMed

Dong, Guoyan; Wang, Xin; Chen, Zhiwu; Lu, Zhenya

2018-05-01

TiO 2 (Degussa P25) photocatalysts harboring abundant oxygen vacancies (Vacuum P25) were manufactured using a simple and economic Vacuum deoxidation process. Control experiments showed that temperature and time of vacuum deoxidation had a significant effect on Vacuum P25 photocatalytic activity. After 240 min of visible light illumination, the optimal Vacuum P25 photocatalysts (vacuum deoxidation treated at 330 °C for 3 h) reach as high as 94% and 88% of photodegradation efficiency for rhodamine B (RhB) and tetracycline, respectively, which are around 4.5 and 4.9 times as that of pristine P25. The XPS, PL and EPR analyses indicated that the oxygen vacancies were produced in the Vacuum P25 during the vacuum deoxidation process. The oxygen vacancy states can produce vacancy energy level located below the conduction band minimum, which resulting in the bandgap narrowing, thus extending the photoresponse wavelength range of Vacuum P25. The positron annihilation analysis indicated that the concentrations ratio of bulk and surface oxygen vacancies could be adjusted by changing the vacuum deoxidation temperature and time. Decreasing the ratio of bulk and surface oxygen vacancies was shown to improve photogenerated electron-hole pair separation efficiency, which leads to an obvious enhancement of the visible photocatalytic activities of Vacuum P25. © 2017 The American Society of Photobiology.

Optomechanical design of the vacuum compatible EXCEDE's mission testbed

NASA Astrophysics Data System (ADS)

Bendek, Eduardo A.; Belikov, Ruslan; Lozi, Julien; Schneider, Glenn; Thomas, Sandrine; Pluzhnik, Eugene; Lynch, Dana

2014-08-01

In this paper we describe the opto-mechanical design, tolerance error budget an alignment strategies used to build the Starlight Suppression System (SSS) for the Exoplanetary Circumstellar Environments and Disk Explorer (EXCEDE) NASA's mission. EXCEDE is a highly efficient 0.7m space telescope concept designed to directly image and spatially resolve circumstellar disks with as little as 10 zodis of circumstellar dust, as well as large planets. The main focus of this work was the design of a vacuum compatible opto-mechanical system that allows remote alignment and operation of the main components of the EXCEDE. SSS, which are: a Phase Induced Amplitude Apodization (PIAA) coronagraph to provide high throughput and high contrast at an inner working angle (IWA) equal to the diffraction limit (IWA = 1.2 l/D), a wavefront (WF) control system based on a Micro-Electro-Mechanical-System deformable mirror (MEMS DM), and low order wavefront sensor (LOWFS) for fine pointing and centering. We describe in strategy and tolerance error budget for this system, which is especially relevant to achieve the theoretical performance that PIAA coronagraph can offer. We also discuss the vacuum cabling design for the actuators, cameras and the Deformable Mirror. This design has been implemented at the vacuum chamber facility at Lockheed Martin (LM), which is based on successful technology development at the Ames Coronagraph Experiment (ACE) facility.

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

Performance of a 12-coil superconducting 'bumpy torus' magnet facility.

NASA Technical Reports Server (NTRS)

Roth, J. R.; Holmes, A. D.; Keller, T. A.; Krawczonek, W. M.

1972-01-01

The NASA-Lewis 'bumpy torus' facility consists of 12 superconducting coils, each 19 cm ID and capable of 3.0 tesla on their axes. The coils are equally spaced around a toroidal array with a major diameter of 1.52 m, and are mounted with the major axis of the torus vertical in a single vacuum tank 2.6 m in diameter. Final shakedown tests of the facility mapped out its magnetic, cryogenic, vacuum, mechanical, and electrical performance. The facility is now ready for use as a plasma physics research facility. A maximum magnetic field on the magnetic axis of 3.23 teslas has been held for a period of more than sixty minutes without a coil normalcy.

APPLICATION OF VACUUM SALT DISTILLATION TECHNOLOGY FOR THE REMOVAL OF FLUORIDE

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

Pierce, R.; Pak, D.

2011-08-10

Vacuum distillation of chloride salts from plutonium oxide (PuO{sub 2}) and simulant PuO{sub 2} has been previously demonstrated at Department of Energy (DOE) sites using kilogram quantities of chloride salt. The apparatus for vacuum distillation contains a zone heated using a furnace and a zone actively cooled using either recirculated water or compressed air. During a vacuum distillation operation, a sample boat containing the feed material is placed into the apparatus while it is cool, and the system is sealed. The system is evacuated using a vacuum pump. Once a sufficient vacuum is attained, heating begins. Volatile salts distill frommore » the heated zone to the cooled zone where they condense, leaving behind the non-volatile materials in the feed boat. The application of vacuum salt distillation (VSD) is of interest to the HB-Line Facility and the MOX Fuel Fabrication Facility (MFFF) at the Savannah River Site (SRS). Both facilities are involved in efforts to disposition excess fissile materials. Many of these materials contain chloride and fluoride salt concentrations which make them unsuitable for dissolution without prior removal of the chloride and fluoride salts. Between September 2009 and January 2011, the Savannah River National Laboratory (SRNL) and HB-Line designed, developed, tested, and successfully deployed a system for the distillation of chloride salts. Subsequent efforts are attempting to adapt the technology for the removal of fluoride. Fluoride salts of interest are less-volatile than the corresponding chloride salts. Consequently, an alternate approach is required for the removal of fluoride without significantly increasing the operating temperature. HB-Line Engineering requested SRNL to evaluate and demonstrate the feasibility of an alternate approach using both non-radioactive simulants and plutonium-bearing materials. Whereas the earlier developments targeted the removal of sodium chloride (NaCl) and potassium chloride (KCl), the

A squeezed light source operated under high vacuum

PubMed Central

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.

EVA Training and Development Facilities

NASA Technical Reports Server (NTRS)

Cupples, Scott

2016-01-01

Overview: Vast majority of US EVA (ExtraVehicular Activity) training and EVA hardware development occurs at JSC; EVA training facilities used to develop and refine procedures and improve skills; EVA hardware development facilities test hardware to evaluate performance and certify requirement compliance; Environmental chambers enable testing of hardware from as large as suits to as small as individual components in thermal vacuum conditions.

Modified coulomb law in a strongly magnetized vacuum.

PubMed

Shabad, Anatoly E; Usov, Vladimir V

2007-05-04

We study the electric potential of a charge placed in a strong magnetic field B>B(0) approximately 4.4x10(13) G, as modified by the vacuum polarization. In such a field the electron Larmour radius is much less than its Compton length. At the Larmour distances a scaling law occurs, with the potential determined by a magnetic-field-independent function. The scaling regime implies short-range interaction, expressed by the Yukawa law. The electromagnetic interaction regains its long-range character at distances larger than the Compton length, the potential decreasing across B faster than along. Correction to the nonrelativistic ground-state energy of a hydrogenlike atom is found. In the limit B = infinity, the modified potential becomes the Dirac delta function plus a regular background. With this potential the ground-state energy is finite--the best pronounced effect of the vacuum polarization.

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.

FACILITY 802B, BATHROOM CONVERTED TO LAUNDRY ROOM, VIEW FACING WESTNORTHWEST. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FACILITY 802B, BATHROOM CONVERTED TO LAUNDRY ROOM, VIEW FACING WEST-NORTHWEST. - Schofield Barracks Military Reservation, Bachelor Officers' Quarters Type, Between Grimes & Tidball Streets near Ayres Avenue, Wahiawa, Honolulu County, HI

Transfer orbit stage mechanisms thermal vacuum test

NASA Technical Reports Server (NTRS)

Oleary, Scott T.

1990-01-01

A systems level mechanisms test was conducted on the Orbital Sciences Corp.'s Transfer Orbit Stage (TOS). The TOS is a unique partially reusable transfer vehicle which will boost a satellite into its operational orbit from the Space Shuttle's cargo bay. The mechanical cradle and tilt assemblies will return to earth with the Space Shuttle while the Solid Rocket Motor (SRM) and avionics package are expended. A mechanisms test was performed on the forward cradle and aft tilting assemblies of the TOS under thermal vacuum conditions. Actuating these assemblies under a 1 g environment and thermal vacuum conditions proved to be a complex task. Pneumatic test fixturing was used to lift the forward cradle, and tilt the SRM, and avionics package. Clinometers, linear voltage displacement transducers, and load cells were used in the thermal vacuum chamber to measure the performance and characteristics of the TOS mechanism assembly. Incorporation of the instrumentation and pneumatic system into the test setup was not routine since pneumatic actuation of flight hardware had not been previously performed in the facility. The methods used are presented along with the problems experienced during the design, setup and test phases.

FACILITY 802B, HALLWAY, LOOKING TOWARD REAR OF HOUSE, VIEW FACING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FACILITY 802B, HALLWAY, LOOKING TOWARD REAR OF HOUSE, VIEW FACING SOUTH-SOUTHWEST. - Schofield Barracks Military Reservation, Bachelor Officers' Quarters Type, Between Grimes & Tidball Streets near Ayres Avenue, Wahiawa, Honolulu County, HI

Comparative Evaluation of Vacuum-based Surface Sampling ...

EPA Pesticide Factsheets

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-

Double Vacuum Bag Process for Resin Matrix Composite Manufacturing

NASA Technical Reports Server (NTRS)

Hou, Tan-Hung (Inventor); Jensen, Brian J. (Inventor)

2007-01-01

A double vacuum bag molding assembly with improved void management and laminate net shape control which provides a double vacuum enviromnent for use in fabricating composites from prepregs containing air and/or volatiles such as reactive resin matrix composites or composites from solvent containing prepregs with non-reactive resins matrices. By using two vacuum environments during the curing process, a vacuum can be drawn during a B-stage of a two-step cycle without placing the composite under significant relative pressure. During the final cure stage, a significant pressure can be applied by releasing the vacuum in one of the two environments. Inner and outer bags are useful for creating the two vacuum environments with a perforated tool intermediate the two. The composite is placed intermediate a tool plate and a caul plate in the first environment with the inner bag and tool plate defining the first environment. The second environment is characterized by the outer bag which is placed over the inner bag and the tool plate.

Space Power Facility at NASA’s Plum Brook Station

NASA Image and Video Library

1969-02-21

Exterior view of the Space Power Facility at the National Aeronautics and Space Administration’s (NASA) Plum Brook Station in Sandusky, Ohio. The $28.4-million facility, which began operations in 1969, is the largest high vacuum chamber ever built. The chamber is 100 feet in diameter and 120 feet high. It produces a vacuum deep enough to simulate the conditions at 300 miles altitude. The facility can sustain a high vacuum; simulate solar radiation via a 4-megawatt quartz heat lamp array, solar spectrum by a 400-kilowatt arc lamp, and cold environments. The Space Power Facility was originally designed to test nuclear power sources for spacecraft during long durations in a space atmosphere, but it was never used for that purpose. The facility’s first test in 1970 involved a 15 to 20-kilowatt Brayton Cycle Power System for space applications. Three different methods of simulating solar heat were employed during the Brayton tests. The facility was also used for jettison tests of the Centaur Standard Shroud. The shroud was designed for the new Titan-Centaur rocket that was scheduled to launch the Viking spacecraft to Mars. The new shroud was tested under conditions that simulated the time from launch to the separation of the stages. Test programs at the facility include high-energy experiments, shroud separation tests, Mars Lander system tests, deployable Solar Sail tests and International Space Station hardware tests.

Investigating steam penetration using thermometric methods in dental handpieces with narrow internal lumens during sterilizing processes with non-vacuum or vacuum processes.

PubMed

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.

Natural vacuum electronics

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.

Characteristics of ring type traveling wave ultrasonic motor in vacuum.

PubMed

Qu, Jianjun; Zhou, Ningning; Tian, Xiu; Jin, Long; Xu, Zhike

2009-03-01

The characteristics of ultrasonic motor strongly depend on the properties of stator/rotor contact interface which are affected by ambient environment. With the developed apparatus, load properties of two ring type traveling wave ultrasonic motors in atmosphere, low vacuum and high vacuum were studied, respectively. Wear of friction material, variations of vacuum degree and the temperature of motor during the experiment were also measured. The results show that load properties of motor A in vacuum were poorer than those in atmosphere, when load torque M(f) was less than 0.55 N m. Compared to motor A, load properties of motor B were affected a little by environmental pressure. Wear of friction material in vacuum was more severe than wear in atmosphere. The temperature of motor in vacuum rose more quickly than it in atmosphere and had not reached equilibrium in 2 h experiment. However, the temperature of motor in atmosphere had reached equilibrium in about forth minutes. Furthermore, outgas was also observed during experiment under vacuum conditions.

Cryopumping of hydrogen in vacuum chambers is aided by catalytic oxidation of hydrogen

NASA Technical Reports Server (NTRS)

Childs, J. H.; Grobman, J.; Rayle, W.

1964-01-01

Vacuum test facilities are required for high speed cryopumping of gaseous hydrogen at low pressures. One method involves the catalytic oxidation of hydrogen and condensation of the resulting water on a liquid nitrogen-cooled surface.

40 CFR Appendix B to Subpart I of... - Allowance for Facilities Planning and Design

Code of Federal Regulations, 2013 CFR

2013-07-01

... Design B Appendix B to Subpart I of Part 35 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Pt. 35, Subpt. I, App. B Appendix B to Subpart I of Part 35—Allowance for Facilities Planning and... initial award amount of all prime subagreements for building the project. b. The initial amounts approved...

40 CFR Appendix B to Subpart I of... - Allowance for Facilities Planning and Design

Code of Federal Regulations, 2011 CFR

2011-07-01

... Design B Appendix B to Subpart I of Part 35 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Pt. 35, Subpt. I, App. B Appendix B to Subpart I of Part 35—Allowance for Facilities Planning and... initial award amount of all prime subagreements for building the project. b. The initial amounts approved...

A NEW, SMALL DRYING FACILITY FOR WET RADIOACTIVE WASTE AND LIQUIDS

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

Oldiges, Olaf; Blenski, Hans-Juergen

2003-02-27

Due to the reason, that in Germany every Waste, that is foreseen to be stored in a final disposal facility or in a long time interim storage facility, it is necessary to treat a lot of waste using different drying technologies. In Germany two different drying facilities are in operation. The GNS Company prefers a vacuum-drying-technology and has built and designed PETRA-Drying-Facilities. In a lot of smaller locations, it is not possible to install such a facility because inside the working areas of that location, the available space to install the PETRA-Drying-Facility is too small. For that reason, GNS decidedmore » to design a new, small Drying-Facility using industrial standard components, applying the vacuum-drying-technology. The new, small Drying-Facility for wet radioactive waste and liquids is presented in this paper. The results of some tests with a prototype facility are shown in chapter 4. The main components of that new facility are described in chapter 3.« less

VACUUM TRAP

DOEpatents

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.

Design and fabrication of the vacuum systems for TPS pulsed septum magnets

NASA Astrophysics Data System (ADS)

Chan, C. K.; Chang, C. C.; Chen, C. L.; Yang, C. S.; Chen, C. S.; Lin, F. Y.; Chen, J. R.

2014-11-01

Three in-air pulsed septum magnets were developed to inject and extract electron beams for the 3 GeV synchrotron facility, the Taiwan Photon Source (TPS). The vacuum chamber is a novel combined aluminium-stainless steel design, using a bimetallic flange to connect the two material types. To evaluate the vacuum performances of these vacuum chambers, we set up a test bench at which we simultaneously measure the rates of thermal outgassing of the aluminium chamber and the septum tube with a throughput method. The test result indicates that the rate q72 of thermal outgassing measured after 1 day from baking at 150 °C was 1×10-13 mbar L s-1 cm-2. The magnetic leakage measurements show the combination of conductor slitting, magnetic shielding and the aluminium vacuum chamber reduce the peak value of the leakage field integral to ~10 G cm along the trajectory of the stored beam.

Viability of Cladosporium herbarum spores under 157 nm laser and vacuum ultraviolet irradiation, low temperature (10 K) and vacuum

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

Coil-On-Plug Ignition for Oxygen/Methane Liquid Rocket Engines in Thermal-Vacuum Environments

NASA Technical Reports Server (NTRS)

Melcher, John C.; Atwell, Matthew J.; Morehead, Robert L.; Hurlbert, Eric A.; Bugarin, Luz; Chaidez, Mariana

2017-01-01

A coil-on-plug ignition system has been developed and tested for Liquid Oxygen (LOX)/liquid methane (LCH4) rocket engines operating in thermal vacuum conditions. The igniters were developed and tested as part of the Integrated Cryogenic Propulsion Test Article (ICPTA), previously tested as part of the Project Morpheus test vehicle. The ICPTA uses an integrated, pressure-fed, cryogenic LOX/LCH4 propulsion system including a reaction control system (RCS) and a main engine. The ICPTA was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. A coil-on-plug ignition system has been developed to successfully demonstrate ignition reliability at these conditions while preventing corona discharge issues. The ICPTA uses spark plug ignition for both the main engine igniter and the RCS. The coil-on-plug configuration eliminates the conventional high-voltage spark plug cable by combining the coil and the spark plug into a single component. Prior to ICPTA testing at Plum Brook, component-level reaction control engine (RCE) and main engine igniter testing was conducted at NASA Johnson Space Center (JSC), which demonstrated successful hot-fire ignition using the coil-on-plug from sea-level ambient conditions down to 10(exp -2) torr. Integrated vehicle hot-fire testing at JSC demonstrated electrical and command/data system performance. Lastly, hot-fire testing at Plum Brook demonstrated successful ignitions at simulated altitude conditions at 30 torr and cold thermal-vacuum conditions at 6 torr. The test campaign successfully proved that coil-on-plug technology will enable integrated LOX/LCH4 propulsion systems in future spacecraft.

Flammability, odor, offgassing, thermal vacuum stability, and compatibility with aerospace fluids of wire insulations

NASA Technical Reports Server (NTRS)

Hirsch, David; Johnson, Harry

1994-01-01

The NASA Lewis Research Center requested NASA Johnson Space Center White Sands Test Facility to conduct flammability, odor, offgassing, thermal vacuum stability, and compatibility tests with aerospace fluids of several wire insulations.

MMS Observatory Thermal Vacuum Results Contamination Summary

NASA Technical Reports Server (NTRS)

Rosecrans, Glenn P.; Errigo, Therese; Brieda, Lubos

2014-01-01

The MMS mission is a constellation of 4 observatories designed to investigate the fundamental plasma physics of reconnection in the Earths magnetosphere. Each spacecraft has undergone extensive environmental testing to prepare it for its minimum 2 year mission. The various instrument suites measure electric and magnetic fields, energetic particles, and plasma composition. Thermal vacuum testing was conducted at the Naval Research Laboratory (NRL) in their Big Blue vacuum chamber. The individual spacecraft were tested and enclosed in a cryopanel enclosure called a Hamster cage. Specific contamination control validations were actively monitored by several QCMs, a facility RGA, and at times, with 16 Ion Gauges. Each spacecraft underwent a bakeout phase, followed by 4 thermal cycles. Unique aspects of the TV environment included slow pump downs with represses, thruster firings, Helium identification, and monitoring pressure spikes with Ion gauges. Various data from these TV tests will be shown along with lessons learned.

Vacuum injection of hydrogen micro-sphere beams

NASA Astrophysics Data System (ADS)

Trostell, Bertil

1995-02-01

The design, construction and operation of a facility producing hydrogen micro-sphere beams in vacuum are summarized. A scheme is utilized, where a liquid hydrogen jet is broken up into droplets, which are injected into vacuum through a capillary at continuum gas flow conditions. In a typical beam, 40 μm diameter micro-spheres, generated at a frequency of 70 kHz, travel at free flight speeds of 60 m/s. The angular divergence of the beam amounts to ±0.04°. The intention is to use the micro-sphere beams as high luminosity internal targets in the WASA experimental station at the CELSIUS cooler storage ring in Uppsala. A time averaged target density profile, having a FWHM and peak density of 3.5 mm and 5 × 10 16 atoms/cm 2, respectively, is obtained 2.5 m downstream of the capillary exit.

Description and Operation of the Mark 1B Plasma Focus Radiation Facility,

DTIC Science & Technology

plasma focus facility (Mk 1B) at The Aerospace Corporation produces x-ray fluences that are applicable to most radiation testing problems (e.g., integrated circuits or transistors). Although the facility has only one beryllium window for exposing 1.6-cm-dia samples to doses of 25 to 45 krad (Si) per shot, three more windows could be added and the additional samples exposed simultaneously. The facility is experiencing switch problems and is presently averaging 50 shots per week--15 shots per day for 3 or 4 days. The results of a comprehensive switch analysis should

Health facility challenges to the provision of Option B+ in western Kenya: a qualitative study

PubMed Central

Akama, Eliud; Bukusi, Elizabeth A; Musoke, Pamela; Nalwa, Wafula Z; Odeny, Thomas A; Onono, Maricianah; Spangler, Sydney A; Turan, Janet M; Wanga, Iris; Abuogi, Lisa L

2017-01-01

Current WHO guidelines recommend lifelong antiretroviral therapy (ART) for all HIV-positive individuals, including pregnant and breastfeeding women (Option B+) in settings with generalized HIV epidemics. While Option B+ is scaled-up in Kenya, insufficient adherence and retention to care could undermine the expected positive impact of Option B+. To explore challenges to the provision of Option B+ at the health facility level, we conducted forty individual gender-matched in-depth interviews with HIV-positive pregnant/postpartum women and their male partners, and four focus groups with thirty health care providers at four health facilities in western Kenya between September-November 2014. Transcripts were coded with the Dedoose software using a coding framework based on the literature, topics from interview guides, and emerging themes from transcripts. Excerpts from broad codes were then fine-coded using an inductive approach. Three major themes emerged: 1) Option B+ specific challenges (same-day initiation into treatment, health care providers unconvinced of the benefits of Option B+, insufficient training); 2) facility resource constraints (staff and drug shortages, long queues, space limitations); and 3) lack of client-friendly services (scolding of patients, inconvenient operating hours, lack of integration of services, administrative requirements). This study highlights important challenges at the health facility level related to Option B+ rollout in western Kenya. Addressing these specific challenges may increase linkage, retention and adherence to life-long ART treatment for pregnant HIV-positive women in Kenya, contribute towards elimination of mother-to-child HIV transmission, and improve maternal and child outcomes. PMID:28207061

Health facility challenges to the provision of Option B+ in western Kenya: a qualitative study.

PubMed

Helova, Anna; Akama, Eliud; Bukusi, Elizabeth A; Musoke, Pamela; Nalwa, Wafula Z; Odeny, Thomas A; Onono, Maricianah; Spangler, Sydney A; Turan, Janet M; Wanga, Iris; Abuogi, Lisa L

2017-03-01

Current WHO guidelines recommend lifelong antiretroviral therapy (ART) for all HIV-positive individuals, including pregnant and breastfeeding women (Option B+) in settings with generalized HIV epidemics. While Option B+ is scaled-up in Kenya, insufficient adherence and retention to care could undermine the expected positive impact of Option B+. To explore challenges to the provision of Option B+ at the health facility level, we conducted forty individual gender-matched in-depth interviews with HIV-positive pregnant/postpartum women and their male partners, and four focus groups with thirty health care providers at four health facilities in western Kenya between September-November 2014. Transcripts were coded with the Dedoose software using a coding framework based on the literature, topics from interview guides, and emerging themes from transcripts. Excerpts from broad codes were then fine-coded using an inductive approach. Three major themes emerged: 1) Option B+ specific challenges (same-day initiation into treatment, health care providers unconvinced of the benefits of Option B+, insufficient training); 2) facility resource constraints (staff and drug shortages, long queues, space limitations); and 3) lack of client-friendly services (scolding of patients, inconvenient operating hours, lack of integration of services, administrative requirements). This study highlights important challenges at the health facility level related to Option B+ rollout in western Kenya. Addressing these specific challenges may increase linkage, retention and adherence to life-long ART treatment for pregnant HIV-positive women in Kenya, contribute towards elimination of mother-to-child HIV transmission, and improve maternal and child outcomes.

Heat Flow Measurement and Analysis of Thermal Vacuum Insulation

NASA Astrophysics Data System (ADS)

Laa, C.; Hirschl, C.; Stipsitz, J.

2008-03-01

A new kind of calorimeter has been developed at Austrian Aerospace to measure specific material parameters needed for the analysis of thermal vacuum insulation. A detailed description of the measuring device and the measurement results will be given in this paper. This calorimeter facility allows to measure the heat flow through the insulation under vacuum conditions in a wide temperature range from liquid nitrogen to ambient. Both boundary temperatures can be chosen within this range. Furthermore the insulation can be characterized at high vacuum or under degraded vacuum, the latter is simulated by using helium or nitrogen gas. The mechanisms of heat transfer have been investigated, namely infrared radiation between the reflective layers of the insulation and conduction through the interleaving spacer material. A mathematical description of the heat flow through the insulation has been derived. Based on this, the heat flow for a typical insulation material has been calculated by finite element analysis by use of the sotware tool Ansys®. Such a transient calculation is needed to determine the time to reach thermal equilibrium, which is mandatory for a proper interpretation and evaluation of the measurement. The new insulation measurement results combined with the proposed type of analysis can be applied to better understand the thermal behavior of any kind of cryogenic system.

Improvement of an Atomic Clock using Squeezed Vacuum

NASA Astrophysics Data System (ADS)

Kruse, I.; Lange, K.; Peise, J.; Lücke, B.; Pezzè, L.; Arlt, J.; Ertmer, W.; Lisdat, C.; Santos, L.; Smerzi, A.; Klempt, C.

2016-09-01

Since the pioneering work of Ramsey, atom interferometers are employed for precision metrology, in particular to measure time and to realize the second. In a classical interferometer, an ensemble of atoms is prepared in one of the two input states, whereas the second one is left empty. In this case, the vacuum noise restricts the precision of the interferometer to the standard quantum limit (SQL). Here, we propose and experimentally demonstrate a novel clock configuration that surpasses the SQL by squeezing the vacuum in the empty input state. We create a squeezed vacuum state containing an average of 0.75 atoms to improve the clock sensitivity of 10000 atoms by 2.05-0.37 +0 .34 dB . The SQL poses a significant limitation for today's microwave fountain clocks, which serve as the main time reference. We evaluate the major technical limitations and challenges for devising a next generation of fountain clocks based on atomic squeezed vacuum.

Thin film microelectronics materials production in the vacuum of space

NASA Astrophysics Data System (ADS)

Ignatiev, A.; Sterling, M.; Horton, C.; Freundlich, A.; Pei, S.; Hill, R.

1997-01-01

The international Space Station era will open up a new dimension in the use of one of the unique attributes of space, vacuum, for the production of advanced semiconductor materials and devices for microelectronics applications. Ultra-vacuum is required for the fabrication in thin film form of high quality semiconductors. This can be accomplished behind a free flying platform similar to the current Wake Shield Facility which is specifically designed to support in-space production. The platform will require apparatus for thin film growth, a robotics interface to allow for the change out of raw materials and the harvesting of finished product, and a servicing plant incorporating Space Station that will support long-term utilization of the platform.

Comparison of vacuum and non-vacuum urine tubes for urinary sediment analysis.

PubMed

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.

40 CFR Appendix B to Subpart I of... - Allowance for Facilities Planning and Design

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Allowance for Facilities Planning and Design B Appendix B to Subpart I of Part 35 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GRANTS AND OTHER FEDERAL ASSISTANCE STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works Pt. 35, Subpt. I, App. B Appendix B to...

Space Simulation, 7th. [facilities and testing techniques

NASA Technical Reports Server (NTRS)

1973-01-01

Space simulation facilities and techniques are outlined that encompass thermal scale modeling, computerized simulations, reentry materials, spacecraft contamination, solar simulation, vacuum tests, and heat transfer studies.

NNSA B-Roll: MOX Facility

ScienceCinema

None

2017-12-09

In 1999, the National Nuclear Security Administration (NNSA) signed a contract with a consortium, now called Shaw AREVA MOX Services, LLC to design, build, and operate a Mixed Oxide (MOX) Fuel Fabrication Facility. This facility will be a major component in the United States program to dispose of surplus weapon-grade plutonium. The facility will take surplus weapon-grade plutonium, remove impurities, and mix it with uranium oxide to form MOX fuel pellets for reactor fuel assemblies. These assemblies will be irradiated in commercial nuclear power reactors.

NNSA B-Roll: MOX Facility

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

None

2010-05-21

In 1999, the National Nuclear Security Administration (NNSA) signed a contract with a consortium, now called Shaw AREVA MOX Services, LLC to design, build, and operate a Mixed Oxide (MOX) Fuel Fabrication Facility. This facility will be a major component in the United States program to dispose of surplus weapon-grade plutonium. The facility will take surplus weapon-grade plutonium, remove impurities, and mix it with uranium oxide to form MOX fuel pellets for reactor fuel assemblies. These assemblies will be irradiated in commercial nuclear power reactors.

Investigation of the cylindrical vacuum hohlraum energy in the first implosion experiment at the SGIII laser facility

NASA Astrophysics Data System (ADS)

Zhang, Huasen; Jiang, Wei; Ge, Fengjun; Song, Peng; Zou, Shiyang; Huang, Tianxuan; Li, Sanwei; Yang, Dong; Li, Zhichao; Hou, Lifei; Guo, Liang; Che, Xingsen; Du, Huabing; Xie, Xufei; He, Xiaoan; Li, Chaoguang; Zha, Weiyi; Xu, Tao; Liu, Yonggang; Wei, Huiyue; Liu, Xiangming; Chen, Zhongjing; Zhang, Xing; Yan, Ji; Pu, Yudong; Peng, Xiaoshi; Li, Yulong; Gu, Peijun; Zheng, Wudi; Liu, Jie; Ding, Yongkun; Zhu, Shaoping

2018-02-01

The cylindrical vacuum hohlraum energy at the SGIII laser facility [X. T. He and W. Y. Zhang, Eur. Phys. J. D 44, 227 (2007) and W. Zheng et al., High Power Laser Sci. Eng. 4, e21 (2016)] is investigated for the first time. The hohlraum size and the laser energy are intermediate between the Nova and NIF typical hohlraum experiments. It is found that the SGIII hohlraum exhibits an x-ray conversion efficiency of about 85%, which is more close to that of the NIF hohlraum. The LARED simulations of the SGIII hohlraum underestimate about 15% of the radiation flux measured from the laser entrance hole, while the capsule radiation drive inferred from the x-ray bangtime is roughly consistent with the experiments. The underestimation of the SGIII hohlraum radiation flux is mainly caused by the more enclosed laser entrance hole in the LARED simulation. The comparison between the SGIII and NIF hohlraum simulations by LARED indicates that the LARED generally underestimates the measured radiation flux by 15% for the high x-ray conversion efficiency hohlraums, while it can roughly predict the capsule radiation drive inside the hohlraum.

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...

Alaskan refiner raced against winter to relocate vacuum unit

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

Gdula, L.M.; Wentworth, J.A.

In late November 1994, San Antonio-based Tesoro Petroleum Corp. and Litwin Engineers and Constructors Inc. completed the relocation and refurbishment of a $25 million vacuum unit at Tesoro`s 72,000 b/d Kenai refinery. The addition of the vacuum distillation unit is a critical component in Tesoro`s market-driven strategy to enhance operating profits by maximizing production of higher-margin products such as gasoline and jet fuel. With its new vacuum distillation unit, Tesoro has reduced production of lower-value residual fuel oil while recovering more lighter, high-value material. The paper discusses the economic and strategic merits of purchasing and relocating an existing vacuum unit,more » the project schedule, new equipment, dismantling and transport, installation, tie-ins and start-up, products, operating changes, corrosion concerns, off gas, steam generation, design changes, environmental issues, reporting requirements, and accomplishments.« less

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…

Astronaut Frederick Gregory vacuums air filters in avionics bay

NASA Image and Video Library

1985-05-03

51B-13-008 (29 April-6 May 1985) --- Astronaut Frederick D. Gregory vacuums air filters in avionics bay. The 51-B pilot is physically located in the overhead area of the middeck on Challenger, but his activity is only a few meters away from the flight deck.

Characterization of the Inductively Heated Plasma Source IPG6-B

NASA Astrophysics Data System (ADS)

Dropmann, Michael; Laufer, Rene; Herdrich, Georg; Matthews, Lorin; Hyde, Truell

2014-10-01

In close collaboration between the Center for Astrophysics, Space Physics and Engineering Research (CASPER) at Baylor University, Texas, and the Institute of Space Systems (IRS) at the University of Stuttgart, Germany, two plasma facilities have been established using the Inductively heated Plasma Generator 6 (IPG6). The facility at Baylor University (IPG6-B) works at a frequency of 13.56 MHz and a maximum power of 15 kW. A vacuum pump of 160 m3/h in combination with a butterfly valve allows pressure control over a wide range. Intended fields of research include basic investigation into thermo-chemistry and plasma radiation, space plasma environments and high heat fluxes e.g. those found in fusion devices or during atmospheric re-entry of spacecraft. After moving the IPG6-B facility to the Baylor Research and Innovation Collaborative (BRIC) it was placed back into operation during the summer of 2014. Initial characterization in the new lab, using a heat flux probe, Pitot probe and cavity calorimeter, has been conducted for Air, Argon and Helium. The results of this characterization are presented.

Brayton Cycle Power System in the Space Power Facility

NASA Image and Video Library

1969-07-21

Set up of a Brayton Cycle Power System test in the Space Power Facility’s massive vacuum chamber at the National Aeronautics and Space Administration’s (NASA) Plum Brook Station in Sandusky, Ohio. The $28.4-million facility, which began operations in 1969, is the largest high vacuum chamber ever built. The chamber is 100 feet in diameter and 120 feet high. It can produce a vacuum deep enough to simulate the conditions at 300 miles altitude. The Space Power Facility was originally designed to test nuclear-power sources for spacecraft, but it was never used for that purpose. The Space Power Facility was first used to test a 15 to 20-kilowatt Brayton Cycle Power System for space applications. Three different methods of simulating solar heat were employed during the tests. Lewis researchers studied the Brayton power system extensively in the 1960s and 1970s. The Brayton engine converted solar thermal energy into electrical power. The system operated on a closed-loop Brayton thermodynamic cycle with a helium-xenon gas mixture as its working fluid. A space radiator was designed to serve as the system’s waste heat rejecter. The radiator was later installed in the vacuum chamber and tested in a simulated space environment to determine its effect on the power conversion system. The Brayton system was subjected to simulated orbits with 62 minutes of sun and 34 minutes of shade.

Acute hepatitis B outbreaks in 2 skilled nursing facilities and possible sources of transmission: North Carolina, 2009-2010.

PubMed

Seña, Arlene C; Moorman, Anne; Njord, Levi; Williams, Roxanne E; Colborn, James; Khudyakov, Yury; Drobenuic, Jan; Xia, Guo-Liang; Wood, Hattie; Moore, Zack

2013-07-01

Acute hepatitis B virus (HBV) infections have been reported in long-term care facilities (LTCFs), primarily associated with infection control breaks during assisted blood glucose monitoring. We investigated HBV outbreaks that occurred in separate skilled nursing facilities (SNFs) to determine factors associated with transmission. Outbreak investigation with case-control studies. Two SNFs (facilities A and B) in Durham, North Carolina, during 2009-2010. Residents with acute HBV infection and controls randomly selected from HBV-susceptible residents during the outbreak period. After initial cases were identified, screening was offered to all residents, with repeat testing 3 months later for HBV-susceptible residents. Molecular testing was performed to assess viral relatedness. Infection control practices were observed. Case-control studies were conducted to evaluate associations between exposures and acute HBV infection in each facility. Six acute HBV cases were identified in each SNF. Viral phylogenetic analysis revealed a high degree of HBV relatedness within, but not between, facilities. No evaluated exposures were significantly associated with acute HBV infection in facility A; those associated with infection in facility B (all odds ratios >20) included injections, hospital or emergency room visits, and daily blood glucose monitoring. Observations revealed absence of trained infection control staff at facility A and suboptimal hand hygiene practices during blood glucose monitoring and insulin injections at facility B. These outbreaks underscore the vulnerability of LTCF residents to acute HBV infection, the importance of surveillance and prompt investigation of incident cases, and the need for improved infection control education to prevent transmission.

Fourth-generation plasma immersion ion implantation and deposition facility for hybrid surface modification layer fabrication.

PubMed

Wang, Langping; Huang, Lei; Xie, Zhiwen; Wang, Xiaofeng; Tang, Baoyin

2008-02-01

The fourth-generation plasma immersion ion implantation and deposition (PIIID) facility for hybrid and batch treatment was built in our laboratory recently. Comparing with our previous PIIID facilities, several novel designs are utilized. Two multicathode pulsed cathodic arc plasma sources are fixed on the chamber wall symmetrically, which can increase the steady working time from 6 h (the single cathode source in our previous facilities) to about 18 h. Meanwhile, the inner diameter of the pulsed cathodic arc plasma source is increased from the previous 80 to 209 mm, thus, large area metal plasma can be obtained by the source. Instead of the simple sample holder in our previous facility, a complex revolution-rotation sample holder composed of 24 shafts, which can rotate around its axis and adjust its position through revolving around the center axis of the vacuum chamber, is fixed in the center of the vacuum chamber. In addition, one magnetron sputtering source is set on the chamber wall instead of the top cover in the previous facility. Because of the above characteristic, the PIIID hybrid process involving ion implantation, vacuum arc, and magnetron sputtering deposition can be acquired without breaking vacuum. In addition, the PIIID batch treatment of cylinderlike components can be finished by installing these components on the rotating shafts on the sample holder.

Physical property characterization of Fe-tube encapsulated and vacuum annealed bulk MgB 2

NASA Astrophysics Data System (ADS)

Awana, V. P. S.; Rawat, Rajeev; Gupta, Anurag; Isobe, M.; Singh, K. P.; Vajpayee, Arpita; Kishan, H.; Takayama-Muromachi, E.; Narlikar, A. V.

2006-08-01

We report the phase formation, and present a detailed study of magnetization and resistivity under magnetic field of MgB 2 polycrystalline bulk samples prepared by the Fe-tube encapsulated and vacuum (10 -5 Torr) annealed (750 ∘C) route. Zero-field-cooled magnetic susceptibility (χ) measurements exhibited a sharp transition to the superconducting state with a sizeable diamagnetic signal at 39 K (Tc). The measured magnetization loops of the samples, despite the presence of flux jumps, exhibited a stable current density (Jc) of around 2.4×10 5 A/cm 2 in up to 2 T (Tesla) field and at temperatures (T) up to 10 K. The upper critical field is estimated from resistivity measurements in various fields and shows a typical value of 8 T at 21 K. Further, χ measurements at an applied field of 0.1 T reveal a paramagnetic Meissner effect (PME) that is briefly discussed.

An electric propulsion long term test facility

NASA Technical Reports Server (NTRS)

Trump, G.; James, E.; Vetrone, R.; Bechtel, R.

1979-01-01

An existing test facility was modified to provide for extended testing of multiple electric propulsion thruster subsystems. A program to document thruster subsystem characteristics as a function of time is currently in progress. The facility is capable of simultaneously operating three 2.7-kW, 30-cm mercury ion thrusters and their power processing units. Each thruster is installed via a separate air lock so that it can be extended into the 7m x 10m main chamber without violating vacuum integrity. The thrusters exhaust into a 3m x 5m frozen mercury target. An array of cryopanels collect sputtered target material. Power processor units are tested in an adjacent 1.5m x 2m vacuum chamber or accompanying forced convection enclosure. The thruster subsystems and the test facility are designed for automatic unattended operation with thruster operation computer controlled. Test data are recorded by a central data collection system scanning 200 channels of data a second every two minutes. Results of the Systems Demonstration Test, a short shakedown test of 500 hours, and facility performance during the first year of testing are presented.

High-energy vacuum birefringence and dichroism in an ultrastrong laser field

NASA Astrophysics Data System (ADS)

Meuren, Sebastian; Bragin, Sergey; Keitel, Christoph H.; di Piazza, Antonino

2017-10-01

The interaction between real photons in vacuum is a long-standing prediction of quantum electrodynamics, which has never been observed experimentally. Upcoming 10 PW laser systems like the Extreme Light Infrastructure (ELI) will provide laser pulses with unprecedented intensities. If combined with highly energetic gamma photons - obtainable via Compton backscattering from laser-wakefield accelerated electron beams - the QED critical field becomes accessible. In we have derived how a generally polarized probe photon beam is influenced by both vacuum birefringence and dichroism in a strong linearly polarized plane-wave laser field. We put forward an experimental scheme to measure these effects in the nontrivial high-energy regime, where the QED critical field is reached and the Euler-Heisenberg approximation, valid for low-frequency electromagnetic fields, breaks down. Our results suggest the feasibility of verifying/rejecting the QED prediction for vacuum birefringence/dichroism at the 3 σ confidence level on the time scale of a few days at several upcoming laser facilities. Now at Princeton University, Princeton, NJ.

[Caesarean section with vacuum extraction of the head].

PubMed

Dimitrov, A; Pavlova, E; Krŭsteva, K; Nikolov, A

2008-01-01

The aim of the study is to investigate the benefits and the limits in using the soft cup vacuum extractor on the fetal scalp during the caesarean section. The prospective study includes 19 cases of caesarean sections (group A), with vacuum assisted delivery using the soft cup vacuum extractor on the fetal scalp (diameter 6 cm) and 25 cases (group B) of caesarean sections with usual, manual extraction of the head assisted by fundal compression. All of the patients had undergone a planned caesarean section on term in absence of uterine activity and preserved amniotic membranes. Our results doesn't show differences in the Apgar score on the first and 5-th minute in the newborns of the two groups. The duration of the scalp traction was significantly shorter (30 +/- 4 sec) in comparison to the classical manual extraction (53 +/- 21 sec). The mean duration for applying the vacuum cup was 10 sec and 25 sec for tractions. The total blood loose and total duration of the caesarean sections were shorter than in the control group. The applied traction with the vacuum cup was sufficient for head extraction and there was no need for additional fundal compression. In conclusion we consider that the extraction of the fetal head in high position in caesarean section with vacuum extractor is an easy, non traumatic and rapid method which can put away the need of rough and prolonged fundal compression and its consequences.

The Classical Vacuum.

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…

Electroweak vacuum instability and renormalized Higgs field vacuum fluctuations in the inflationary universe

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 .

42 CFR 52b.7 - How is the grantee obligated to use the facility?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 1 2014-10-01 2014-10-01 false How is the grantee obligated to use the facility? 52b.7 Section 52b.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.7 How is the grantee obligated to use the...

42 CFR 52b.7 - How is the grantee obligated to use the facility?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 1 2013-10-01 2013-10-01 false How is the grantee obligated to use the facility? 52b.7 Section 52b.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.7 How is the grantee obligated to use the...

42 CFR 52b.7 - How is the grantee obligated to use the facility?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 1 2012-10-01 2012-10-01 false How is the grantee obligated to use the facility? 52b.7 Section 52b.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.7 How is the grantee obligated to use the...

42 CFR 52b.7 - How is the grantee obligated to use the facility?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 1 2011-10-01 2011-10-01 false How is the grantee obligated to use the facility? 52b.7 Section 52b.7 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.7 How is the grantee obligated to use the...

A highly miniaturized vacuum package for a trapped ion atomic clock

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

Schwindt, Peter D. D., E-mail: pschwin@sandia.gov; Jau, Yuan-Yu; Partner, Heather

2016-05-15

We report on the development of a highly miniaturized vacuum package for use in an atomic clock utilizing trapped ytterbium-171 ions. The vacuum package is approximately 1 cm{sup 3} in size and contains a linear quadrupole RF Paul ion trap, miniature neutral Yb sources, and a non-evaporable getter pump. We describe the fabrication process for making the Yb sources and assembling the vacuum package. To prepare the vacuum package for ion trapping, it was evacuated, baked at a high temperature, and then back filled with a helium buffer gas. Once appropriate vacuum conditions were achieved in the package, it wasmore » sealed with a copper pinch-off and was subsequently pumped only by the non-evaporable getter. We demonstrated ion trapping in this vacuum package and the operation of an atomic clock, stabilizing a local oscillator to the 12.6 GHz hyperfine transition of {sup 171}Y b{sup +}. The fractional frequency stability of the clock was measured to be 2 × 10{sup −11}/τ{sup 1/2}.« less

Recent advances and applications of gas chromatography vacuum ultraviolet spectroscopy.

PubMed

Santos, Inês C; Schug, Kevin A

2017-01-01

The vacuum ultraviolet spectrophotometer was developed recently as an alternative to existing gas chromatography detectors. This detector measures the absorption of gas-phase chemical species in the range of 120-240 nm, where all chemical compounds present unique absorption spectra. Therefore, qualitative analysis can be performed and quantification follows standard Beer-Lambert law principles. Different fields of application, such as petrochemical, food, and environmental analysis have been explored. Commonly demonstrated is the capability for facile deconvolution of co-eluting analytes. The concept of additive absorption for co-eluting analytes has also been advanced for classification and speciation of complex mixtures using a data treatment procedure termed time interval deconvolution. Furthermore, pseudo-absolute quantitation can be performed for system diagnosis, as well as potentially calibrationless quantitation. In this manuscript an overview of these features, the vacuum ultraviolet spectrophotometer instrumentation, and performance capabilities are given. A discussion of the applications of the vacuum ultraviolet detector is provided by describing and discussing the papers published thus far since 2014. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

Development of High Interruption Capability Vacuum Circuit Breaker -Technology of Vacuum Arc Control-

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.

Electroweak vacuum instability and renormalized Higgs field vacuum fluctuations in the inflationary universe

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

Power Control and Monitoring Requirements for Thermal Vacuum/Thermal Balance Testing of the MAP Observatory

NASA Technical Reports Server (NTRS)

Johnson, Chris; Hinkle, R. Kenneth (Technical Monitor)

2002-01-01

The specific heater control requirements for the thermal vacuum and thermal balance testing of the Microwave Anisotropy Probe (MAP) Observatory at the Goddard Space Flight Center (GSFC) in Greenbelt, Maryland are described. The testing was conducted in the 10m wide x 18.3m high Space Environment Simulator (SES) Thermal Vacuum Facility. The MAP thermal testing required accurate quantification of spacecraft and fixture power levels while minimizing heater electrical emissions. The special requirements of the MAP test necessitated construction of five (5) new heater racks.

Vacuum aspiration with the IPAS Modified Gynecologic Syringe.

PubMed

Balogh, S A

1983-01-01

The IPAS Modified Gynecologic Syringe was compared with the electric pump and standard hand pump in a clinical trial of 1227 women undergoing vacuum aspiration. This modified double-valve syringe was designed to fit larger 8 mm, 10 mm and 12 mm cannulae, which are more suitable for late first trimester procedures. The study was conducted at four centers in which the double-valve syringe was used alternately with the vacuum source normally used at each clinic. Although there were notable inter-center differences with respect to certain outcome variables, results were similar for procedures performed at the same center. The only significant finding was the lower proportion of women requiring D & C to complete uterine evacuation among double-valve syringe patients than among hand pump cases at one center. The data indicate that the double-valve syringe is safe and effective for uterine aspiration in women up to 14 weeks' gestation and may be preferable for use in clinics with limited facilities.

Thermodynamic modelling of phase equilibrium in system Ti-B-Si-C, synthesis and phases composition of borides and carbides layers on titanic alloyVT-1 at electron beam treatment in vacuum

NASA Astrophysics Data System (ADS)

Smirnyagina, N. N.; Khaltanova, V. M.; Lapina, A. E.; Dasheev, D. E.

2017-01-01

Composite layers on the basis of carbides and borides the titan and silicon on titanic alloy VT-1 are generated at diffused saturation in vacuum. Formation in a composite of MAX phase Ti3SiC2 is shown. Thermodynamic research of phase equilibrium in systems Ti-Si-C and Ti-B-C in the conditions of high vacuum is executed. The thermodynamics, formation mechanisms of superfirm layers borides and carbides of the titan and silicon are investigated.

Status of NSLS-II Storage Ring Vacuum Systems

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

Doom,L.; Hseuh,H.; Ferreira, M.

2009-05-04

National Synchrotron Light Source II (NSLS-II), being constructed at Brookhaven National Laboratory, is a 3-GeV, high-flux and high- brightness synchrotron radiation facility with a nominal current of 500 mA. The storage ring vacuum system will have extruded aluminium chambers with ante-chamber for photon fans and distributed NEG strip pumping. Discrete photon absorbers will be used to intercept the un-used bending magnet radiation. In-situ bakeout will be implemented to achieve fast conditioning during initial commissioning and after interventions.

47 CFR 36.341 - Cable and wire facilities expenses-Account 6410 (Class B telephone companies); Accounts 6411...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Cable and wire facilities expenses-Account 6410... Operating Expenses and Taxes Cable and Wire Facilities Expenses § 36.341 Cable and wire facilities expenses... network cable, aerial wire, and conduit systems. (b) The general method of separating cable and wire...

47 CFR 36.341 - Cable and wire facilities expenses-Account 6410 (Class B telephone companies); Accounts 6411...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 2 2011-10-01 2011-10-01 false Cable and wire facilities expenses-Account 6410... Operating Expenses and Taxes Cable and Wire Facilities Expenses § 36.341 Cable and wire facilities expenses... network cable, aerial wire, and conduit systems. (b) The general method of separating cable and wire...

109(b) State Training Center Facility Assessment, Program Evaluation, and Guide Development. Final Report.

ERIC Educational Resources Information Center

Miklas, Michael P., Jr.

Section 109(b) of the 1972 Federal Water Pollution Control Act Amendments authorized funding for the construction of statewide water treatment training facilities. Described in this report is work conducted by Southwest Research Institute (SwRI) to: (1) aid in developing updated 109(b) Guidance Documents; (2) characterize and evaluate existing…

Thermal-vacuum response of polymer matrix composites in space

NASA Technical Reports Server (NTRS)

Tennyson, R. C.; Matthews, R.

1993-01-01

This report describes a thermal-vacuum outgassing model and test protocol for predicting outgassing times and dimensional changes for polymer matrix composites. Experimental results derived from 'control' samples are used to provide the basis for analytical predictions to compare with the outgassing response of Long Duration Exposure Facility (LDEF) flight samples. Coefficient of thermal expansion (CTE) data are also presented. In addition, an example is given illustrating the dimensional change of a 'zero' CTE laminate due to moisture outgassing.

Arsenic interactions with a fullerene-like BN cage in the vacuum and aqueous phase.

PubMed

Beheshtian, Javad; Peyghan, Ali Ahmadi; Bagheri, Zargham

2013-02-01

Adsorption of arsenic ions, As (III and V), on the surface of fullerene-like B(12)N(12) cage has been explored in vacuum and aqueous phase using density functional theory in terms of Gibbs free energies, enthalpies, geometry, and density of state analysis. It was found that these ions can be strongly chemisorbed on the surface of the cluster in both vacuum and aqueous phase, resulting in significant changes in its electronic properties so that the cluster transforms from a semi-insulator to a semiconductor. The solvent significantly affects the geometry parameters and electronic properties of the As/B(12)N(12) complexes and the interaction between components is considerably weaker in the aqueous phase than that in the vacuum.

Radiation hard vacuum switch

DOEpatents

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.

Radiation hard vacuum switch

DOEpatents

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.

In-Vacuum Photogrammetry of a 10-Meter Solar Sail

NASA Technical Reports Server (NTRS)

Meyer, Chris G.; Jones, Thomas W.; Lunsford, Charles B.; Pappa, Richard S.

2005-01-01

In July 2004, a 10-meter solar sail structure developed by L Garde, Inc. was tested in vacuum at the NASA Glenn 30-meter Plum Brook Space Power Facility in Sandusky, Ohio. The three main objections of the test were to demonstrate unattended deployment from a stowed configuration, to measure the deployed shape of the sail at both ambient and cryogenic room temperatures, and to measure the deployed structural dynamic characteristics (vibration modes). This paper summarizes the work conducted to fulfill the second test objective. The deployed shape was measured photogrammetrically in vacuum conditions with four 2-megapixel digital video cameras contained in custom made pressurized canisters. The canisters included high-intensity LED ring lights to illuminate a grid of retroreflective targets distributed on the solar sail. The test results closely matched pre-test photogrammetry numerical simulations and compare well with ABAQUS finite-element model predictions.

Indian LSSC (Large Space Simulation Chamber) facility

NASA Technical Reports Server (NTRS)

Brar, A. S.; Prasadarao, V. S.; Gambhir, R. D.; Chandramouli, M.

1988-01-01

The Indian Space Agency has undertaken a major project to acquire in-house capability for thermal and vacuum testing of large satellites. This Large Space Simulation Chamber (LSSC) facility will be located in Bangalore and is to be operational in 1989. The facility is capable of providing 4 meter diameter solar simulation with provision to expand to 4.5 meter diameter at a later date. With such provisions as controlled variations of shroud temperatures and availability of infrared equipment as alternative sources of thermal radiation, this facility will be amongst the finest anywhere. The major design concept and major aspects of the LSSC facility are presented here.

A novel dehydration technique for carrot slices implementing ultrasound and vacuum drying methods.

PubMed

Chen, Zhi-Gang; Guo, Xiao-Yu; Wu, Tao

2016-05-01

A novel drying technique using a combination of ultrasound and vacuum dehydration was developed to shorten the drying time and improve the quality of carrot slices. Carrot slices were dried with ultrasonic vacuum (USV) drying and vacuum drying at 65 °C and 75 °C. The drying rate was significantly influenced by the drying techniques and temperatures. Compared with vacuum drying, USV drying resulted in a 41-53% decrease in the drying time. The drying time for the USV and vacuum drying techniques at 75 °C was determined to be 140 and 340 min for carrot slices, respectively. The rehydration potential, nutritional value (retention of β-carotene and ascorbic acid), color, and textural properties of USV-dried carrot slices are predominately better compared to vacuum-dried carrot slices. Moreover, lower energy consumption was used in the USV technique. The drying data (time versus moisture ratio) were successfully fitted to Wang and Singh model. Copyright © 2015. Published by Elsevier B.V.

Profile of hepatitis B and C virus infection in prisoners in Lubuk Pakam correctional facilities

NASA Astrophysics Data System (ADS)

Rey, I.; Saragih, R. H.; Effendi-YS, R.; Sembiring, J.; Siregar, G. A.; Zain, L. H.

2018-03-01

Prisoners in correctional facilities are predisposed to chronic viral infections because of their high-risk behaviors or unsafe lifestyle. The economic and public health burden of chronic hepatitis B and C and its sequelae need to be addressed, such as by finding the risk factors and therefore reducing the spread of HCV and HBV infection in prisons. This study aimed to see the profile of Hepatitis B and C Virus Infection in prisoners in Lubuk Pakam Correctional Facilities. This cross-sectional study was in Lubuk Pakam Correctional Facilities in 2016. From 1114 prisoners in Lubuk Pakam correctional facility, we randomly examined 120 prisoners for HBV and HCV serology markers. From 120 prisoners, six prisoners were HBV positive, 21 prisoners were HCV positive and one prisoner positive for both HCV and HBV infection. The most common risk factors for prisoners getting HBV infection are tattoos and free sex (36.4% and 36.4%, respectively). The most common risk factors for HCV infection in prisoners are tattoos and free sex (40% and 35%, respectively).

Assessment of heavy metals exposure, noise and thermal safety in the ambiance of a vacuum metallurgy separation system for recycling heavy metals from crushed e-wastes.

PubMed

Zhan, Lu; Xu, Zhenming

2014-12-01

Vacuum metallurgy separation (VMS) is a technically feasible method to recover Pb, Cd and other heavy metals from crushed e-wastes. To further determine the environmental impacts and safety of this method, heavy metals exposure, noise and thermal safety in the ambiance of a vacuum metallurgy separation system are evaluated in this article. The mass concentrations of total suspended particulate (TSP) and PM10 are 0.1503 and 0.0973 mg m(-3) near the facilities. The concentrations of Pb, Cd and Sn in TSP samples are 0.0104, 0.1283 and 0.0961 μg m(-3), respectively. Health risk assessments show that the hazard index of Pb is 3.25 × 10(-1) and that of Cd is 1.09 × 10(-1). Carcinogenic risk of Cd through inhalation is 1.08 × 10(-5). The values of the hazard index and risk indicate that Pb and Cd will not cause non-cancerous effects or carcinogenic risk on workers. The noise sources are mainly the mechanical vacuum pump and the water cooling pump. Both of them have the noise levels below 80 dB (A). The thermal safety assessment shows that the temperatures of the vacuum metallurgy separation system surface are all below 303 K after adopting the circulated water cooling and heat insulation measures. This study provides the environmental information of the vacuum metallurgy separation system, which is of assistance to promote the industrialisation of vacuum metallurgy separation for recovering heavy metals from e-wastes. © The Author(s) 2014.

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.

Lipid oxidation and color changes of goose meat stored under vacuum and modified atmosphere conditions.

PubMed

Orkusz, A; Haraf, G; Okruszek, A; Werenska-Sudnik, M

2017-03-01

The objective of the work was to investigate the color and lipid oxidation changes of goose breast meat packaged in vacuum and modified atmosphere (MA) conditions consisting of 80% O2, 20% CO2, and stored in refrigerated conditions at 4°C. Color stability was monitored by determining total heme pigments concentration; relative concentration of myoglobin, oxymyoglobin, and metmyoglobin; parameters of color L*, a*, b*, and sensory evaluation of the surface color. Lipid stability was measured by determining thiobarbituric acid reactive substances (TBARS). The samples were examined in 24 h after slaughter (unpacked muscles) and on d 4, 7, 9, 11 of storage (muscles packed in vacuum and in MA). Through the time of storage, samples packed in MA had higher TBARS values in comparison to the meat packed in vacuum. For samples packed in two types of atmospheres, the total pigments concentration decreased gradually within 11 d of storage. It was observed that relative metmyoglobin concentration increased whereas relative oxymyoglobin concentration decreased in total heme pigments in the MA stored muscle. The relative concentration of all three myoglobin forms sample packed in vacuum remained unchanged. The color parameters (L*, a*, b*) did not change for 11 d of storage for the vacuum packed meat. The value of the color parameter a* decreased and the value of the color parameters L* and b* increased in the samples packaged in MA. The data prove that if you store goose meat in MA (consisting of 80% O2, 20% CO2) or vacuum, the unchanged surface color is preserved for 9 and 11 day, respectively.Vacuum appears to be a better method as regards the maintaining of lipid stability in goose meat. © 2016 Poultry Science Association Inc.

Performance of a 12-coil superconducting bumpy torus magnet facility

NASA Technical Reports Server (NTRS)

Roth, J. R.; Holmes, A. D.; Keller, T. A.; Krawczonek, W. M.

1972-01-01

The bumpy torus facility consists of 12 superconducting coils, each 19 cm i.d. and capable of 3.0 teslas on their axes. The coils are equally spaced around a toroidal array with a major diameter of 1.52 m, and are mounted with the major axis of the torus vertical in a single vacuum tank 2.6 m in diameter. Final shakedown tests of the facility mapped out its magnetic, cryogenic, vacuum, mechanical, and electrical performance. The facility is now ready for use as a plasma physics research facility. A maximum magnetic field on the magnetic axis of 3.23 teslas was held for a period of more than sixty minutes without a coil normalcy. The design field was 3.00 teslas. The steady-state liquid helium boil-off rate was 87 liters per hour of liquid helium without the coils charged. The coil array was stable when subjected to an impulsive loading, even with the magnets fully charged. When the coils were charged to a maximum magnetic field of 3.35 teslas, the system was driven normal without damage.

Vacuum Virtues

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…

James Webb Space Telescope (JWST) Integrated Science Instruments Module (ISIM) Cryo-Vacuum (CV) Test Campaign Summary

NASA Technical Reports Server (NTRS)

Yew, Calinda; Lui, Yan; Whitehouse, Paul; Banks, Kimberly

2016-01-01

JWST Integrated Science Instruments Module (ISIM) completed its system-level space simulation testing program at the NASA Goddard Space Flight Center (GSFC). In March 2016, ISIM was successfully delivered to the next level of integration with the Optical Telescope Element (OTE), to form OTIS (OTE + ISIM), after concluding a series of three cryo-vacuum (CV) tests. During these tests, the complexity of the mission has generated challenging requirements that demand highly reliable system performance and capabilities from the Space Environment Simulator (SES) vacuum chamber. The first test served as a risk reduction test; the second test provided the initial verification of the fully-integrated flight instruments; and the third test verified the system in its final flight configuration following mechanical environmental tests (vibration and acoustics). From one test to the next, shortcomings of the facility were uncovered and associated improvements in operational capabilities and reliability of the facility were required to enable the project to verify system-level requirements. This paper: (1) provides an overview of the integrated mechanical and thermal facility systems required to achieve the objectives of JWST ISIM testing, (2) compares the overall facility performance and instrumentation results from the three ISIM CV tests, and (3) summarizes lessons learned from the ISIM testing campaign.

Ultrahigh vacuum process for the deposition of nanotubes and nanowires

DOEpatents

Das, Biswajit; Lee, Myung B

2015-02-03

A system and method A method of growing an elongate nanoelement from a growth surface includes: a) cleaning a growth surface on a base element; b) providing an ultrahigh vacuum reaction environment over the cleaned growth surface; c) generating a reactive gas of an atomic material to be used in forming the nanoelement; d) projecting a stream of the reactive gas at the growth surface within the reactive environment while maintaining a vacuum of at most 1.times.10.sup.-4 Pascal; e) growing the elongate nanoelement from the growth surface within the environment while maintaining the pressure of step c); f) after a desired length of nanoelement is attained within the environment, stopping direction of reactive gas into the environment; and g) returning the environment to an ultrahigh vacuum condition.

Microfabricated triggered vacuum switch

DOEpatents

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.

Facile Aqueous Phase Synthesis of Pd3Cu-B/C Nanocatalyst for Glucose Electrooxidation

NASA Astrophysics Data System (ADS)

Chai, Dan; Lu, Haibin; Wang, Yaqian; Hua, Xiuwen; Ren, Na; Zhang, Xiongwen

2018-01-01

A novel Pd3Cu-B/C nanocatalyst was facilely synthesized through an aqueous phase process. And it was developed for use in the glucose electrooxidation reaction in fuel cells. Cyclic voltammetry shown that the electrochemical surface area of Pd3Cu-B/C is 2.25 times that of Pd/C. Glucose electrooxidation curves revealed that peak current on the Pd3Cu-B/C is actually 1.73 times of the Pd/C. This high performance of Pd3Cu-B/C could be ascribed to the synergistic effect between Pd, Cu and B.

Measurement of the accumulation of water ice on optical components in cryogenic vacuum environments

NASA Astrophysics Data System (ADS)

Moeller, Trevor M.; Montgomery Smith, L.; Collins, Frank G.; Labello, Jesse M.; Rogers, James P.; Lowry, Heard S.; Crider, Dustin H.

2012-11-01

Standard vacuum practices mitigate the presence of water vapor and contamination inside cryogenic vacuum chambers. However, anomalies can occur in the facility that can cause the accumulation of amorphous water ice on optics and test articles. Under certain conditions, the amorphous ice on optical components shatters, which leads to a reduction in signal or failure of the component. An experiment was performed to study and measure the deposition of water (H2O) ice on optical surfaces under high-vacuum cryogenic conditions. Water was introduced into a cryogenic vacuum chamber, via a hydrated molecular sieve zeolite, through an effusion cell and impinged upon a quartz-crystal microbalance (QCM) and first-surface gold-plated mirror. A laser and photodiode setup, external to the vacuum chamber, monitored the multiple-beam interference reflectance of the ice-mirror configuration while the QCM measured the mass deposition. Data indicates that water ice, under these conditions, accumulates as a thin film on optical surfaces to thicknesses over 45 microns and can be detected and measured by nonintrusive optical methods which are based upon multiple-beam interference phenomena. The QCM validated the interference measurements. This experiment established proof-of-concept for a miniature system for monitoring ice accumulation within the chamber.

Influence of Gap Distance on Vacuum Arc Characteristics of Cup Type AMF Electrode in Vacuum Interrupters

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.

PREFACE: International Symposium on `Vacuum Science and Technology' (IVS 2007)

NASA Astrophysics Data System (ADS)

Mittal, K. C.; Gupta, S. K.

2008-03-01

equipments, accessories, products etc by different manufacturers and suppliers has been organized at the venue of the symposium hall for the benefit of the participants. The interest shown by the exhibitors reveals that the industry has come of age and the advances that have taken place over the years is quite significant. During the symposium, the Indian Vacuum Society felicitated two distinguished personalities who have contributed significantly for the development of vacuum science and technology in the country. The C AMBASANKARAN memorial and Smt SHAKUNTALABAI VYAWAHARE memorial Awards were also conferred on the two best contributed papers. A committee constituted by the Symposium Organizing Committee evaluated the relevance, scientific content, and clarity of presentation to decide the award winning papers. It is hoped that the discussion generated by the delegates at the symposium will help in a better understanding vacuum science and technology. K C Mittal Convener S K Gupta Co Convener International Advisory Committee Kakodkar, Anil DAE/India, Chairman Badve, Cdr A.V.(IN Retd.) Pfeiffer Vac India Banerjee, S. BARC/India Bhandari, R.K. BRNS/India Chander, Shekhar CEERI/India Chopra, K.L. IIT Delhi/India Day, Chris ITER Grover, R.B DAE,BARC/India Jakub, Szajman VSA/ Australia Jayaraj, R.N. NFC/India Kamath, H.S. BARC/India Kaw, P.K. IPR/India Kobayashi, M. VSJ/Japan Kumar, Lalit MTRDC, India Kumar, Vikram NPL., India Langley, Robert AVS, USA Larour, Jean Ecole/France Mendonsa, R.H. Lawrence and Mayo Myneni, Ganapatirao Jlab/USA Narsaiah, S.V. HHV Padamsee, Hasan Cornell/USA Pillay, R.G. TIFR Raj, Baldev IGCAR/India Raju, P.T. IVS/India Ramasami, T. DST/India Ray, A.K. BARC/India Reid, RJ IUVSTA/UK Roy, Amit IUAC/india Sahni, V.C. RRCAT, BARC/India Schamiloglu, E. UNM/USA Shankara, K.N. VSSC,ISRO/India Sinha, Bikash VEC,SINP/India Strubin, P. CERN/Switzerland Local Organizing Committee Ray, A.K. BARC (Chairman) Kailas, S. BARC, (Co Chairman) Chakravarty, D.P. BARC

Carbon Nanotube Vacuum Gauges Utilizing Long, Dissipative Tubes

NASA Technical Reports Server (NTRS)

Kaul, Anupama B.; Manohara, Harish M.

2008-01-01

CNT Vacuum Gauges: a) have a broad range of pressure response from 760 - 10(exp -6) Torr. b) have current changes approx. 100's nA in high vacuum regime (10(exp -6) Torr) and sensitivity increases with power and substrate removal. c) have a negative dR/dT (TCR negative) where a thermal hopping energy E(sub a) was determined to be approx. 40 meV. d) have compatible fabrication requirements for their integration with micromachined structures. e) can be operated at low power (nW - micro-W). f) have an active device region footprint of < 10 sq microns. g) are non-intrusive due to small size and passive operation.

49 CFR 393.51 - Warning signals, air pressure and vacuum gauges.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Warning signals, air pressure and vacuum gauges... REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Brakes § 393.51 Warning signals, air pressure... paragraphs (b), (c), (d) or (e) of this section. (b) Hydraulic brakes. Vehicles manufactured on or after...

49 CFR 393.51 - Warning signals, air pressure and vacuum gauges.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Warning signals, air pressure and vacuum gauges... REGULATIONS PARTS AND ACCESSORIES NECESSARY FOR SAFE OPERATION Brakes § 393.51 Warning signals, air pressure... paragraphs (b), (c), (d) or (e) of this section. (b) Hydraulic brakes. Vehicles manufactured on or after...

Space Power Facility-Capabilities for Space Environmental Testing Within a Single Facility

NASA Technical Reports Server (NTRS)

Sorge, Richard N.

2013-01-01

The purpose of this paper is to describe the current and near-term environmental test capabilities of the NASA Glenn Research Center's Space Power Facility (SPF) located at Sandusky, Ohio. The paper will present current and near-term capabilities for conducting electromagnetic interference and compatibility testing, base-shake sinusoidal vibration testing, reverberant acoustic testing, and thermal-vacuum testing. The paper will also present modes of transportation, handling, ambient environments, and operations within the facility to conduct those tests. The SPF is in the midst of completing and activating new or refurbished capabilities which, when completed, will provide the ability to conduct most or all required full-scale end-assembly space simulation tests at a single test location. It is envisioned that the capabilities will allow a customer to perform a wide range of space simulation tests in one facility at reasonable cost.

Canadian macromolecular crystallography facility: a suite of fully automated beamlines.

PubMed

Grochulski, Pawel; Fodje, Michel; Labiuk, Shaunivan; Gorin, James; Janzen, Kathryn; Berg, Russ

2012-06-01

The Canadian light source is a 2.9 GeV national synchrotron radiation facility located on the University of Saskatchewan campus in Saskatoon. The small-gap in-vacuum undulator illuminated beamline, 08ID-1, together with the bending magnet beamline, 08B1-1, constitute the Canadian Macromolecular Crystallography Facility (CMCF). The CMCF provides service to more than 50 Principal Investigators in Canada and the United States. Up to 25% of the beam time is devoted to commercial users and the general user program is guaranteed up to 55% of the useful beam time through a peer-review process. CMCF staff provides "Mail-In" crystallography service to users with the highest scored proposals. Both beamlines are equipped with very robust end-stations including on-axis visualization systems, Rayonix 300 CCD series detectors and Stanford-type robotic sample auto-mounters. MxDC, an in-house developed beamline control system, is integrated with a data processing module, AutoProcess, allowing full automation of data collection and data processing with minimal human intervention. Sample management and remote monitoring of experiments is enabled through interaction with a Laboratory Information Management System developed at the facility.

X-Ray Calibration Facility/Advanced Video Guidance Sensor Test

NASA Technical Reports Server (NTRS)

Johnston, N. A. S.; Howard, R. T.; Watson, D. W.

2004-01-01

The advanced video guidance sensor was tested in the X-Ray Calibration facility at Marshall Space Flight Center to establish performance during vacuum. Two sensors were tested and a timeline for each are presented. The sensor and test facility are discussed briefly. A new test stand was also developed. A table establishing sensor bias and spot size growth for several ranges is detailed along with testing anomalies.

Safety studies on vacuum insulated liquid helium cryostats

NASA Astrophysics Data System (ADS)

Weber, C.; Henriques, A.; Zoller, C.; Grohmann, S.

2017-12-01

The loss of insulating vacuum is often considered as a reasonable foreseeable accident for the dimensioning of cryogenic safety relief devices (SRD). The cryogenic safety test facility PICARD was designed at KIT to investigate such events. In the course of first experiments, discharge instabilities of the spring loaded safety relief valve (SRV) occurred, the so-called chattering and pumping effects. These instabilities reduce the relief flow capacity, which leads to impermissible over-pressures in the system. The analysis of the process dynamics showed first indications for a smaller heat flux than the commonly assumed 4W/cm2. This results in an oversized discharge area for the reduced relief flow rate, which corresponds to the lower heat flux. This paper presents further experimental investigations on the venting of the insulating vacuum with atmospheric air under variation of the set pressure (p set) of the SRV. Based on dynamic process analysis, the results are discussed with focus on effective heat fluxes and operating characteristics of the spring-loaded SRV.

Risk factors for anal sphincter tears in vacuum-assisted delivery.

PubMed

Ryman, P; Ahlberg, M; Ekéus, C

2015-10-01

The aim of the present study was to describe the prevalence of anal sphincter tears (AST) in relation to obstetric management and technique during vacuum extraction deliveries (VE) (re: indications, the station of the fetal head at application of the cup, number of tractions, the length for the extraction, cup detachments, pain relief, episiotomy, fetal presentation, and experience of the operator) as well as maternal and infant anthropometrics. Descriptive study. Data on six hundred vacuum extraction deliveries were consecutively collected from six different delivery units in Sweden. Each unit contributed with data on 100 deliveries. The final study population included 596 women who delivered by vacuum extraction. There was no correlation between the management of the vacuum extraction and risk for anal sphincter tear. Women from Africa had nearly a fourfold risk for anal sphincter tear during vacuum-assisted delivery compared with Swedish-born women (OR 3.82 CI 1.47-9.89). Compared with infants with birth weight less than 4000 g, birth weight above 4000 g was associated with increased risk of AST (OR 1.87 CI 1.06-3.28). In this study, the obstetric management in VE-assisted deliveries did not impact the risk of AST. Copyright © 2015 Elsevier B.V. All rights reserved.

42 CFR 52b.11 - What are the requirements for acquisition and modernization of existing facilities?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 1 2012-10-01 2012-10-01 false What are the requirements for acquisition and modernization of existing facilities? 52b.11 Section 52b.11 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.11 What are the...

42 CFR 52b.11 - What are the requirements for acquisition and modernization of existing facilities?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 1 2013-10-01 2013-10-01 false What are the requirements for acquisition and modernization of existing facilities? 52b.11 Section 52b.11 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.11 What are the...

42 CFR 52b.11 - What are the requirements for acquisition and modernization of existing facilities?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 1 2014-10-01 2014-10-01 false What are the requirements for acquisition and modernization of existing facilities? 52b.11 Section 52b.11 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.11 What are the...

42 CFR 52b.11 - What are the requirements for acquisition and modernization of existing facilities?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 1 2011-10-01 2011-10-01 false What are the requirements for acquisition and modernization of existing facilities? 52b.11 Section 52b.11 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.11 What are the...

42 CFR 52b.11 - What are the requirements for acquisition and modernization of existing facilities?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false What are the requirements for acquisition and modernization of existing facilities? 52b.11 Section 52b.11 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.11 What are the...

The U.S. Lab placed in vacuum chamber for leak test

NASA Technical Reports Server (NTRS)

2000-01-01

In the Operations and Checkout Building, the U.S. Lab, a component of the International Space Station, is lowered into a three-story vacuum chamber. The 32,000-pound scientific research lab, named Destiny, is the first Space Station element to spend seven days in the renovated vacuum chamber for a leak test. Destiny is scheduled to be launched on Shuttle mission STS-98, the 5A assembly mission, targeted for Jan. 18, 2001. During the mission, the crew will install the Lab in the Space Station during a series of three space walks. The STS-98 mission will provide the Station with science research facilities and expand its power, life support and control capabilities. The U.S. Lab module continues a long tradition of microgravity materials research, first conducted by Skylab and later Shuttle and Spacelab missions. Destiny is expected to be a major feature in future research, providing facilities for biotechnology, fluid physics, combustion, and life sciences research.

Vacuum probe surface sampler

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.

13. Building H9; view of stainless steel probes and vacuum ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. Building H-9; view of stainless steel probes and vacuum line, looking W. (Ryan and Harms) - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

Comparison of work rates, energy expenditure, and perceived exertion during a 1-h vacuuming task with a backpack vacuum cleaner and an upright vacuum cleaner.

PubMed

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.

Development of a EUV Test Facility at the Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

West, Edward; Pavelitz, Steve; Kobayashi, Ken; Robinson, Brian; Cirtain, Johnathan; Gaskin, Jessica; Winebarger, Amy

2011-01-01

This paper will describe a new EUV test facility that is being developed at the Marshall Space Flight Center (MSFC) to test EUV telescopes. Two flight programs, HiC - high resolution coronal imager (sounding rocket) and SUVI - Solar Ultraviolet Imager (GOES-R), set the requirements for this new facility. This paper will discuss those requirements, the EUV source characteristics, the wavelength resolution that is expected and the vacuum chambers (Stray Light Facility, Xray Calibration Facility and the EUV test chamber) where this facility will be used.

Credit PSR. This interior view shows the vacuum tumble dryer. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Credit PSR. This interior view shows the vacuum tumble dryer. The tumble dryer is lined with a water jacket to maintain temperature during the drying of ammonium perchlorate ("AP"); water enters and exits the dryer jacket through the pipe fittings along the horizontal center line of the dryer. The wall at the right is constructed to blow out in the event of an explosion - Jet Propulsion Laboratory Edwards Facility, Oxidizer Dryer Building, Edwards Air Force Base, Boron, Kern County, CA

A radiation hard vacuum switch

DOEpatents

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.

Comparison of vacuum rise time, vacuum limit accuracy, and occlusion break surge of 3 new phacoemulsification systems.

PubMed

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.

Air bearing vacuum seal assembly

DOEpatents

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.

Findings from a hepatitis B birth dose assessment in health facilities in the Philippines: opportunities to engage the private sector.

PubMed

Patel, Minal K; Capeding, Rosario Z; Ducusin, Joyce U; de Quiroz Castro, Maricel; Garcia, Luzviminda C; Hennessey, Karen

2014-09-03

Hepatitis B vaccination in the Philippines was introduced in 1992 to reduce the high burden of chronic hepatitis B virus (HBV) infection in the population; in 2007, a birth dose (HepB-BD) was introduced to decrease perinatal HBV transmission. Timely HepB-BD coverage, defined as doses given within 24h of birth, was 40% nationally in 2011. A first step in improving timely HepB-BD coverage is to ensure that all newborns born in health facilities are vaccinated. In order to assess ways of improving the Philippines' HepB-BD program, we evaluated knowledge, attitudes, and practices surrounding HepB-BD administration in health facilities. Teams visited selected government clinics, government hospitals, and private hospitals in regions with low reported HepB-BD coverage and interviewed immunization and maternity staff. HepB-BD coverage was calculated in each facility for a 3-month period in 2011. Of the 142 health facilities visited, 12 (8%) did not provide HepB-BD; seven were private hospitals and five were government hospitals. Median timely HepB-BD coverage was 90% (IQR 80%-100%) among government clinics, 87% (IQR 50%-97%) among government hospitals, and 50% (IQR 0%-90%) among private hospitals (p=0.02). The private hospitals were least likely to receive supervision (53% vs. 6%-31%, p=0.0005) and to report vaccination data to the national Expanded Programme on Immunization (36% vs. 96%-100%, p<0.0001). Private sector hospitals in the Philippines, which deliver 18% of newborns, had the lowest timely HepB-BD coverage. Multiple avenues exist to engage the private sector in hepatitis B prevention including through existing laws, newborn health initiatives, hospital accreditation processes, and raising awareness of the government's free vaccine program. Copyright © 2013 World Health Organization (WHO). Published by Elsevier Ltd.. All rights reserved.

Interplay between Vacuum-Grown Monolayers of Alkylphosphonic Acids and the Performance of Organic Transistors Based on Dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene.

PubMed

Hannah, Stuart; Cardona, Javier; Lamprou, Dimitrios A; Šutta, Pavol; Baran, Peter; Al Ruzaiqi, Afra; Johnston, Karen; Gleskova, Helena

2016-09-28

Monolayers of six alkylphosphonic acids ranging from C8 to C18 were prepared by vacuum evaporation and incorporated into low-voltage organic field-effect transistors based on dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DNTT). Similar to solution-assembled monolayers, the molecular order for vacuum-deposited monolayers improved with increasing length of the aliphatic tail. At the same time, Fourier transform infrared (FTIR) measurements suggested lower molecular coverage for longer phosphonic acids. The comparison of FTIR and vibration frequencies calculated by density functional theory indicated that monodentate bonding does not occur for any phosphonic acid. All monolayers exhibited low surface energy of ∼17.5 mJ/m(2) with a dominating Lifshitz-van der Waals component. Their surface roughness was comparable, while the nanomechanical properties were varied but not correlated to the length of the molecule. However, large improvement in transistor performance was observed with increasing length of the aliphatic tail. Upon going from C8 to C18, the mean threshold voltage decreased from -1.37 to -1.24 V, the field-effect mobility increased from 0.03 to 0.33 cm(2)/(V·s), the off-current decreased from ∼8 × 10(-13) to ∼3 × 10(-13) A, and for transistors with L = 30 μm the on-current increased from ∼3 × 10(-8) to ∼2 × 10(-6) A, and the on/off-current ratio increased from ∼3 × 10(4) to ∼4 × 10(6). Similarly, transistors with longer phosphonic acids exhibited much better air and bias-stress stability. The achieved transistor performance opens up a completely "dry" fabrication route for ultrathin dielectrics and low-voltage organic transistors.

Tensile Properties and Structure of Several Superalloys after Long- Term Exposure to LiF and Vacuum at 1173 K

NASA Astrophysics Data System (ADS)

Whittenberger, J. D.

1995-12-01

The use of the solid- to- liquid phase transformation of LiF to store thermal energy is under consideration for a space- based solar dynamic system. Although advantageous in terms of its energy density, the melting point of this salt (1121K) is beyond the commonly accepted upper- use temperature of 1100 K for chromium- bearing superalloys in vacuum. However, one commercially available nickel- base superalloy (Hastelloy B- 2) is chromium free; unfortunately, because of its high molybdenum content, this alloy can form phases that cause high- temperature embrittlement. To test the suitability of Hastelloy B- 2, it has been exposed to molten LiF, its vapor and vacuum at 1173 K for 2500, 5000, and 10 h. For control, the chromium- containing cobalt- base Haynes alloy 188 and nickel- base Haynes alloy 230 were also exposed to LiF and vacuum at 1173 K for 5000 h. Neither LiF nor vacuum exposures had any significant effect on Hastelloy B- 2 in terms of microstructural surface damage or weight change. Measurement of the post exposure tensile properties of Hastelloy B- 2, nevertheless, revealed low tensile ductility at 1050 K. Such embrittlement and low strength at elevated temperatures appear to preclude the use of Hastelloy B- 2 as a containment material for LiF. Little evidence of significant attack by LiF was seen in either of the chromium- containing superalloys; however, considerable weight loss and near- surface microstructural damage occurred in both alloys exposed to vacuum. Although measurement of the post exposure room-temperature tensile properties of Haynes alloys 188 and 230 revealed no significant loss of strength or ductility, the severe degree of microstructural damage found in unshielded alloys exposed to vacuum indicates that chromium-bearing superalloys might also be unsuitable for prolonged containment of LiF in space above 1100 K. Keywords

DFL, Canada's Space AIT Facilities - Current and Planned Capabilities

NASA Astrophysics Data System (ADS)

Singhal, R.; Mishra, S.; Choueiry, E.; Dumoulin, J.; Ahmed, S.

2004-08-01

The David Florida Laboratory (DFL) of the Canadian Space Agency is the Canadian national ISO 9001:2000 registered facility for the assembly, integration, and (environmental) testing of space hardware. This paper briefly describes the three main qualification facilities: Structural Qualification Facilities (SQF); Radio Frequency Qualification Facilities (RFQF); and Thermal Qualification Facilities (TQF). The paper also describes the planned/new upgrades/improvements to the DFL's existing capabilities. These include: cylindrical near-field antenna measurement system, current capabilities in multi-frequency multi-band passive intermodulation (PIM) measurement; combined thermal/vibration test facility, improvement in efficiency and performance of the photogrammetry capability, acquisition of an additional mass properties measurement system for small and micro-satellites; combined control and data acquisition system for all existing thermal vacuum facilities, plus a new automatic thermal control system and hypobaric chamber.

Effective Porosity Measurements by Wet- and Dry-type Vacuum Saturations using Process-Programmable Vacuum Saturation System

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.

Extreme plasma states in laser-governed vacuum breakdown.

PubMed

Efimenko, Evgeny S; Bashinov, Aleksei V; Bastrakov, Sergei I; Gonoskov, Arkady A; Muraviev, Alexander A; Meyerov, Iosif B; Kim, Arkady V; Sergeev, Alexander M

2018-02-05

Triggering vacuum breakdown at laser facility is expected to provide rapid electron-positron pair production for studies in laboratory astrophysics and fundamental physics. However, the density of the produced plasma may cease to increase at a relativistic critical density, when the plasma becomes opaque. Here, we identify the opportunity of breaking this limit using optimal beam configuration of petawatt-class lasers. Tightly focused laser fields allow generating plasma in a small focal volume much less than λ 3 and creating extreme plasma states in terms of density and produced currents. These states can be regarded to be a new object of nonlinear plasma physics. Using 3D QED-PIC simulations we demonstrate a possibility of reaching densities over 10 25  cm -3 , which is an order of magnitude higher than expected earlier. Controlling the process via initial target parameters provides an opportunity to reach the discovered plasma states at the upcoming laser facilities.

Aerospace test facilities at NASA LERC Plumbrook

NASA Astrophysics Data System (ADS)

1992-10-01

An overview of the facilities and research being conducted at LeRC's Plumbrook field station is given. The video highlights four main structures and explains their uses. The Space Power Facility is the worlds largest space environment simulation chamber, where spacebound hardware is tested in simulations of the vacuum and extreme heat and cold of the space plasma environment. This facility was used to prepare Atlas 1 rockets to ferry CRRES into orbit; it will also be used to test space nuclear electric power generation systems. The Spacecraft Propulsion Research Facility allows rocket vehicles to be hot fired in a simulated space environment. In the Cryogenic Propellant Tank Facility, researchers are developing technology for storing and transferring liquid hydrogen in space. There is also a Hypersonic Wind Tunnel which can perform flow tests with winds up to Mach 7.

Method of correcting eddy current magnetic fields in particle accelerator vacuum chambers

DOEpatents

Danby, G.T.; Jackson, J.W.

1990-03-19

A method for correcting magnetic field aberrations produced by eddy currents induced in a particle accelerator vacuum chamber housing is provided wherein correction windings are attached to selected positions on the housing and the windings are energized by transformer action from secondary coils, which coils are inductively coupled to the poles of electro-magnets that are powered to confine the charged particle beam within a desired orbit as the charged particles are accelerated through the vacuum chamber by a particle-driving rf field. The power inductively coupled to the secondary coils varies as a function of variations in the power supplied by the particle-accelerating rf field to a beam of particles accelerated through the vacuum chamber, so the current in the energized correction coils is effective to cancel eddy current flux fields that would otherwise be induced in the vacuum chamber by power variations (dB/dt) in the particle beam.

42 CFR 52b.8 - How will NIH monitor the use of facilities constructed with federal funds?

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 1 2014-10-01 2014-10-01 false How will NIH monitor the use of facilities constructed with federal funds? 52b.8 Section 52b.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.8 How will NIH...

42 CFR 52b.8 - How will NIH monitor the use of facilities constructed with federal funds?

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 1 2012-10-01 2012-10-01 false How will NIH monitor the use of facilities constructed with federal funds? 52b.8 Section 52b.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.8 How will NIH...

42 CFR 52b.8 - How will NIH monitor the use of facilities constructed with federal funds?

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 1 2013-10-01 2013-10-01 false How will NIH monitor the use of facilities constructed with federal funds? 52b.8 Section 52b.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.8 How will NIH...

42 CFR 52b.8 - How will NIH monitor the use of facilities constructed with federal funds?

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 1 2011-10-01 2011-10-01 false How will NIH monitor the use of facilities constructed with federal funds? 52b.8 Section 52b.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.8 How will NIH...

42 CFR 52b.8 - How will NIH monitor the use of facilities constructed with federal funds?

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false How will NIH monitor the use of facilities constructed with federal funds? 52b.8 Section 52b.8 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GRANTS NATIONAL INSTITUTES OF HEALTH CONSTRUCTION GRANTS § 52b.8 How will NIH...

The U.S. Lab is placed in vacuum chamber for leak test

NASA Technical Reports Server (NTRS)

2000-01-01

With the lid of the three-story vacuum chamber in place, a worker on top checks release of the cables. Inside the chamber is the U.S. Lab, a component of the International Space Station. The 32,000-pound scientific research lab, named Destiny, is the first Space Station element to spend seven days in the renovated vacuum chamber for a leak test. Destiny is scheduled to be launched on Shuttle mission STS-98, the 5A assembly mission, targeted for Jan. 18, 2001. During the mission, the crew will install the Lab in the Space Station during a series of three space walks. The STS-98 mission will provide the Station with science research facilities and expand its power, life support and control capabilities. The U.S. Lab module continues a long tradition of microgravity materials research, first conducted by Skylab and later Shuttle and Spacelab missions. Destiny is expected to be a major feature in future research, providing facilities for biotechnology, fluid physics, combustion, and life sciences research.

The U.S. Lab is placed in vacuum chamber for leak test

NASA Technical Reports Server (NTRS)

2000-01-01

A worker in the Operations and Checkout Building checks the placement of the lid on the vacuum chamber containing the U.S. Lab, a component of the International Space Station. The 32,000-pound scientific research lab, named Destiny, is the first Space Station element to spend seven days in the renovated vacuum chamber for a leak test. Destiny is scheduled to be launched on Shuttle mission STS-98, the 5A assembly mission, targeted for Jan. 18, 2001. During the mission, the crew will install the Lab in the Space Station during a series of three space walks. The STS-98 mission will provide the Station with science research facilities and expand its power, life support and control capabilities. The U.S. Lab module continues a long tradition of microgravity materials research, first conducted by Skylab and later Shuttle and Spacelab missions. Destiny is expected to be a major feature in future research, providing facilities for biotechnology, fluid physics, combustion, and life sciences research.

The U.S. Lab is placed in vacuum chamber for leak test

NASA Technical Reports Server (NTRS)

2000-01-01

Workers in the Operations and Checkout Building check the placement of the lid on the vacuum chamber containing the U.S. Lab, a component of the International Space Station. The 32,000-pound scientific research lab, named Destiny, is the first Space Station element to spend seven days in the renovated vacuum chamber for a leak test. Destiny is scheduled to be launched on Shuttle mission STS-98, the 5A assembly mission, targeted for Jan. 18, 2001. During the mission, the crew will install the Lab in the Space Station during a series of three space walks. The STS-98 mission will provide the Station with science research facilities and expand its power, life support and control capabilities. The U.S. Lab module continues a long tradition of microgravity materials research, first conducted by Skylab and later Shuttle and Spacelab missions. Destiny is expected to be a major feature in future research, providing facilities for biotechnology, fluid physics, combustion, and life sciences research.

Infra-red lamp panel study and assessment application to thermal vacuum testing of sigma telescope

NASA Technical Reports Server (NTRS)

Mauduyt, Jacques; Merlet, Joseph; Poux, Christiane

1986-01-01

A research and development program of the Infra-Red Test has been conducted by the French Space Agency (CNES). A choice, after characterization, among several possibilities has been made on the type of methods and facilities for the I.R. test. An application to the Thermal Vacuum Test of the SIGMA Telescope is described.

Modernization of B-2 Data, Video, and Control Systems Infrastructure

NASA Technical Reports Server (NTRS)

Cmar, Mark D.; Maloney, Christian T.; Butala, Vishal D.

2012-01-01

The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Spacecraft Propulsion Research Facility, commonly referred to as B-2, is NASA s third largest thermal-vacuum facility with propellant systems capability. B-2 has completed a modernization effort of its facility legacy data, video and control systems infrastructure to accommodate modern integrated testing and Information Technology (IT) Security requirements. Integrated systems tests have been conducted to demonstrate the new data, video and control systems functionality and capability. Discrete analog signal conditioners have been replaced by new programmable, signal processing hardware that is integrated with the data system. This integration supports automated calibration and verification of the analog subsystem. Modern measurement systems analysis (MSA) tools are being developed to help verify system health and measurement integrity. Legacy hard wired digital data systems have been replaced by distributed Fibre Channel (FC) network connected digitizers where high speed sampling rates have increased to 256,000 samples per second. Several analog video cameras have been replaced by digital image and storage systems. Hard-wired analog control systems have been replaced by Programmable Logic Controllers (PLC), fiber optic networks (FON) infrastructure and human machine interface (HMI) operator screens. New modern IT Security procedures and schemes have been employed to control data access and process control flows. Due to the nature of testing possible at B-2, flexibility and configurability of systems has been central to the architecture during modernization.

Modernization of B-2 Data, Video, and Control Systems Infrastructure

NASA Technical Reports Server (NTRS)

Cmar, Mark D.; Maloney, Christian T.; Butala, Vishal D.

2012-01-01

The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Spacecraft Propulsion Research Facility, commonly referred to as B-2, is NASA's third largest thermal-vacuum facility with propellant systems capability. B-2 has completed a modernization effort of its facility legacy data, video and control systems infrastructure to accommodate modern integrated testing and Information Technology (IT) Security requirements. Integrated systems tests have been conducted to demonstrate the new data, video and control systems functionality and capability. Discrete analog signal conditioners have been replaced by new programmable, signal processing hardware that is integrated with the data system. This integration supports automated calibration and verification of the analog subsystem. Modern measurement systems analysis (MSA) tools are being developed to help verify system health and measurement integrity. Legacy hard wired digital data systems have been replaced by distributed Fibre Channel (FC) network connected digitizers where high speed sampling rates have increased to 256,000 samples per second. Several analog video cameras have been replaced by digital image and storage systems. Hard-wired analog control systems have been replaced by Programmable Logic Controllers (PLC), fiber optic networks (FON) infrastructure and human machine interface (HMI) operator screens. New modern IT Security procedures and schemes have been employed to control data access and process control flows. Due to the nature of testing possible at B-2, flexibility and configurability of systems has been central to the architecture during modernization.

The vacuum tribology model (VTM) of TriboLAB

NASA Astrophysics Data System (ADS)

Garmendia, I.; Landaberea, A.; Anglada, E.; Fernández-Sanz, R.; Santiago, R.; Herrada, F.; Encinas, J. M.

2003-09-01

TriboLAB is a tribology instrument that is planned for installation in the EuteF Flight Segment Platform, along with several other European scientific instruments. EuteF will be fixed onto an Express Pallet Adapter (ExPA), which provides standard structural, mechanical, electrical and communications interfaces to the Columbus External Payload Facility of the International Space Station (ISS). As a part of the model philosophy, a vacuum tribological model (VTM) has been developed to generate "on ground" tribological data of selected lubricants. The idea is to compare the results obtained "on ground" with those that will be produced in the space, in order to investigate the different behaviors of same tribological films and to be able to compare the performance of specific lubricants in Low Earth Orbit (LEO) conditions. The VTM is composed of six double experiment cells that perform respectively ball bearing (BB) experiments (with liquid and solid lubrication) and pin-on-disk (PoD) tests of solid lubricants. Thin films of alloyed MoS2 are being tested in the VTM under controlled vacuum conditions. In this work, the two sections of the VTM are described.

Optimal Operation of a Josephson Parametric Amplifier for Vacuum Squeezing

NASA Astrophysics Data System (ADS)

Malnou, M.; Palken, D. A.; Vale, Leila R.; Hilton, Gene C.; Lehnert, K. W.

2018-04-01

A Josephson parametric amplifier (JPA) can create squeezed states of microwave light, lowering the noise associated with certain quantum measurements. We experimentally study how the JPA's pump influences the phase-sensitive amplification and deamplification of a coherent tone's amplitude when that amplitude is commensurate with vacuum fluctuations. We predict and demonstrate that, by operating the JPA with a single current pump whose power is greater than the value that maximizes gain, the amplifier distortion is reduced and, consequently, squeezing is improved. Optimizing the singly pumped JPA's operation in this fashion, we directly observe 3.87 ±0.03 dB of vacuum squeezing over a bandwidth of 30 MHz.

Fermionic vacuum polarization in a higher-dimensional global monopole spacetime

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

Bezerra de Mello, E. R.

2007-12-15

In this paper we analyze the vacuum polarization effects associated with a massless fermionic field in a higher-dimensional global monopole spacetime in the 'braneworld' scenario. In this context we admit that our Universe, the bulk, is represented by a flat (n-1)-dimensional brane having a global monopole in an extra transverse three-dimensional submanifold. We explicitly calculate the renormalized vacuum average of the energy-momentum tensor, B}(x)>{sub Ren}, admitting the global monopole as being a pointlike object. We observe that this quantity depends crucially on the value of n, and provide explicit expressions to it for specific values attributed to n.

Vacuum leak detector and method

DOEpatents

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.

Marination and Physicochemical Characteristics of Vacuum-aged Duck Breast Meat.

PubMed

Khan, Muhammad Issa; Lee, Hyun Jung; Kim, Hyun-Joo; Young, Hae In; Lee, Haelim; Jo, Cheorun

2016-11-01

We investigated marinade absorption and physicochemical characteristics of vacuum-aged duck breasts that were halved and individually vacuum-packed for chiller aging at 4°C for 14 d. One half was marinated for 0, 7, or 14 d, while the second half was used as a control. Marinade absorption, cooking loss, cooking yield, texture profile, pH, color, protein solubility, and thiobarbituric acid reactive substances (TBARS) values were evaluated, and protein sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was performed. Marinade absorption and pH did not vary significantly after 14 d of aging. Marination increased the pH, color (a* and b*) values, and cooking yield and reduced cooking loss. TBARS values significantly increased with aging time, but were significantly reduced by marination. Myofibril and total protein solubility increased with aging and marination, while SDS-PAGE showed protein degradation. Hence, aging and marination can be used simultaneously to improve physicochemical quality and cooking yield of vacuum-aged duck breast.

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.

James Webb Space Telescope (JWST) Integrated Science Instruments Module (ISIM) Cryo-Vacuum (CV) Test Campaign Summary

NASA Technical Reports Server (NTRS)

Yew, Calinda; Whitehouse, Paul; Lui, Yan; Banks, Kimberly

2016-01-01

JWST Integrated Science Instruments Module (ISIM) has completed its system-level testing program at the NASA Goddard Space Flight Center (GSFC). In March 2016, ISIM was successfully delivered for integration with the Optical Telescope Element (OTE) after the successful verification of the system through a series of three cryo-vacuum (CV) tests. The first test served as a risk reduction test; the second test provided the initial verification of the fully-integrated flight instruments; and the third test verified the system in its final flight configuration. The complexity of the mission has generated challenging requirements that demand highly reliable system performance and capabilities from the Space Environment Simulator (SES) vacuum chamber. As JWST progressed through its CV testing campaign, deficiencies in the test configuration and support equipment were uncovered from one test to the next. Subsequent upgrades and modifications were implemented to improve the facility support capabilities required to achieve test requirements. This paper: (1) provides an overview of the integrated mechanical and thermal facility systems required to achieve the objectives of JWST ISIM testing, (2) compares the overall facility performance and instrumentation results from the three ISIM CV tests, and (3) summarizes lessons learned from the ISIM testing campaign.

Double-Vacuum-Bag Process for Making Resin-Matrix Composites

NASA Technical Reports Server (NTRS)

Bradford, Larry J.

2007-01-01

A double-vacuum-bag process has been devised as a superior alternative to a single-vacuum-bag process used heretofore in making laminated fiber-reinforced resin-matrix composite-material structural components. This process is applicable to broad classes of high-performance matrix resins including polyimides and phenolics that emit volatile compounds (solvents and volatile by-products of resin-curing chemical reactions) during processing. The superiority of the double-vacuum-bag process lies in enhanced management of the volatile compounds. Proper management of volatiles is necessary for making composite-material components of high quality: if not removed and otherwise properly managed, volatiles can accumulate in interior pockets as resins cure, thereby forming undesired voids in the finished products. The curing cycle for manufacturing a composite laminate containing a reactive resin matrix usually consists of a two-step ramp-and-hold temperature profile and an associated single-step pressure profile as shown in Figure 1. The lower-temperature ramp-and-hold step is known in the art as the B stage. During the B stage, prepregs are heated and volatiles are generated. Because pressure is not applied at this stage, volatiles are free to escape. Pressure is applied during the higher-temperature ramp-and-hold step to consolidate the laminate and impart desired physical properties to the resin matrix. The residual volatile content and fluidity of the resin at the beginning of application of consolidation pressure are determined by the temperature and time parameters of the B stage. Once the consolidation pressure is applied, residual volatiles are locked in. In order to produce a void-free, high-quality laminate, it is necessary to design the curing cycle to obtain the required residual fluidity and the required temperature at the time of application of the consolidation pressure.

Venturi air-jet vacuum ejectors for high-volume atmospheric sampling on aircraft platforms

NASA Technical Reports Server (NTRS)

Hill, Gerald F.; Sachse, Glen W.; Young, Douglas C.; Wade, Larry O.; Burney, Lewis G.

1992-01-01

Documentation of the installation and use of venturi air-jet vacuum ejectors for high-volume atmospheric sampling on aircraft platforms is presented. Information on the types of venturis that are useful for meeting the pumping requirements of atmospheric-sampling experiments is also presented. A description of the configuration and installation of the venturi system vacuum line is included with details on the modifications that were made to adapt a venturi to the NASA Electra aircraft at GSFC, Wallops Flight Facility. Flight test results are given for several venturis with emphasis on applications to the Differential Absorption Carbon Monoxide Measurement (DACOM) system at LaRC. This is a source document for atmospheric scientists interested in using the venturi systems installed on the NASA Electra or adapting the technology to other aircraft.

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

Cryogenic testing of Planck sorption cooler test facility

NASA Technical Reports Server (NTRS)

Zhang, B.; Pearson, D.; Borders, J.; Franklin, B.; Prina, M.; Hardy, J.; Crumb, D.

2004-01-01

A test facility has been upgraded in preparation for testing of two hydrogen sorption cryocoolers operating at 18/20 K. these sorption coolers are currently under development at the Jet Propulsion Laboratory. This work summarizes the scope of the test facility upgrade, including design for cryogenic cooling power delivery, system thermal management, insulation schemes, and data acquisition techniques. Ground support equipment for the sorption coolers, structural features of the test chamber, and the vacuum system involved for system testing will also be described in detail.

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...

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.

Aerospace Test Facilities at NASA LeRC Plumbrook

NASA Technical Reports Server (NTRS)

1992-01-01

An overview of the facilities and research being conducted at LeRC's Plumbrook field station is given. The video highlights four main structures and explains their uses. The Space Power Facility is the world's largest space environment simulation chamber, where spacebound hardware is tested in simulations of the vacuum and extreme heat and cold of the space plasma environment. This facility was used to prepare Atlas 1 rockets to ferry CRRES into orbit; it will also be used to test space nuclear electric power generation systems. The Spacecraft Propulsion Research Facility allows rocket vehicles to be hot fired in a simulated space environment. In the Cryogenic Propellant Tank Facility, researchers are developing technology for storing and transferring liquid hydrogen in space. There is also a Hypersonic Wind Tunnel which can perform flow tests with winds up to Mach 7.

Exploring vacuum birefringence based on a 100 PW laser and an x-ray free electron laser beam

NASA Astrophysics Data System (ADS)

Shen, Baifei; Bu, Zhigang; Xu, Jiancai; Xu, Tongjun; Ji, Liangliang; Li, Ruxin; Xu, Zhizhan

2018-04-01

Exploring vacuum birefringence with the station of extreme light at Shanghai Coherent Light Facility is considered. Laser pulses of intensity beyond 1023 W cm-2 are capable of polarizing the vacuum due to the ultra-strong electro-magnetic fields. The subtle difference of the vacuum refractive indexes along electric and magnetic fields leads to a birefringence effect for lights propagating through. The vacuum birefringence effect can now be captured by colliding a hard x-ray free electron laser (XFEL) beam with a high-power laser. The initial XFEL beam of pure linear polarization is predicated to gain a very small ellipticity after passing through the laser stimulated vacuum. Various interaction geometries are considered, showing that the estimated ellipticity lies between 1.8 × 10-10 and 10-9 for a 100 PW laser interacting with a 12.9 keV XFEL beam, approaching the threshold for todays’ polarity detection technique. The detailed experimental set-up is designed, including the polarimeter, the focusing compound refractive lens and the optical path. When taking into account the efficiencies of the x-ray instruments, it is found that about 10 polarization-flipped x-ray photons can be detected for a single shot for our design. Considering the background noise level, accumulating runs are necessary to obtain high confident measurement.

Inspection qualification (IQ) and operational qualification (OQ) for a vacuum freeze-dryer--Part I. General discussion.

PubMed

Jennings, T A; Scheer, A; Emodi, A; Puderbach, L; King, S; Norton, T

1996-01-01

The principle objectives of this paper are (a), to develop the rationale for conducting an inspection qualification (IQ) and operational qualification (OQ) of a vacuum freeze-dryer; (b), to identify the key elements that require verification for completion of the IQ; and (c), to establish the necessary environmental and operational parameters necessary for the OQ of the vacuum freeze-dryer.

Lunar placement of Mars quarantine facility

NASA Technical Reports Server (NTRS)

Davidson, James E.; Mitchell, W. F.

1988-01-01

Advanced mission scenarios are currently being contemplated that would call for the retrieval of surface samples from Mars, from a comet, and from other places in the solar system. An important consideration for all of these sample return missions is quarantine. Quarantine facilities on the Moon offer unique advantages over other locations. The Moon offers gravity, distance, and vacuum. It is sufficiently near the Earth to allow rapid resupply and easy communication. It is sufficiently distant to lessen the psychological impact of a quarantine facility on Earth's human inhabitants. Finally, the Moon is airless, and seems to be devoid of life. It is, therefore, more suited to contamination control efforts.

Improving Vacuum Cleaners

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.

Cleaning of inner vacuum surfaces in the Uragan-3M facility by radio-frequency discharges

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

Lozin, A. V., E-mail: alexlozin@meta.ua; Moiseenko, V. E.; Grigor’eva, L. I.

2013-08-15

A method for cleaning vacuum surfaces by a low-temperature (T{sub e} ∼ 10 eV) relatively dense (n{sub e} ≈ 10{sup 12} cm{sup −3}) plasma of an RF discharge was developed and successfully applied at the Uragan-3M torsatron. The convenience of the method is that it can be implemented with the same antenna system and RF generators that are used to produce and heat the plasma in the operating mode and does not require retuning the frequencies of the antennas and RF generators. The RF discharge has a high efficiency from the standpoint of cleaning vacuum surfaces. After performing a seriesmore » of cleanings by the low-temperature RF discharge plasma (about 20000 pulses), (i) the intensity of the CIII impurity line was substantially reduced, (ii) a quasi-steady operating mode with a duration of up to 50 ms, a plasma density of n{sub e} ≈ 10{sup 12} cm{sup −3}, and an electron temperature of up to T{sub e} ∼ 1 keV was achieved, and (iii) mass spectrometric analysis of the residual gas in the chamber indicated a significant reduction in the impurity content.« less

Introduction to the magnet and vacuum systems of an electron storage ring

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

Weng, W.T.

An accelerator or storage ring complex is a concerted interplay of various functional systems. For the convenience of discussion we can divide it into the following systems: injector, magnet, RF, vacuum, instrumentation and control. In addition, the conventional construction of the building and radiation safety consideration are also needed and finally the beam lines, detector, data acquisition and analysis set-ups for research programs. Dr. L. Teng has given a comprehensive review of the whole complex and the operation of such a facility. I concentrate on the description of magnet and vacuum systems. Only the general function of each system andmore » the basic design concepts will be introduced, no detailed engineering practice will be given which will be best done after a machine design is produced. For further understanding and references a table of bibliography is provided at the end of the paper.« less

Quantification of rectifications for the Northwestern University Flexible Sub-Ischial Vacuum Socket.

PubMed

Fatone, Stefania; Johnson, William Brett; Tran, Lilly; Tucker, Kerice; Mowrer, Christofer; Caldwell, Ryan

2017-06-01

The fit and function of a prosthetic socket depend on the prosthetist's ability to design the socket's shape to distribute load comfortably over the residual limb. We recently developed a sub-ischial socket for persons with transfemoral amputation: the Northwestern University Flexible Sub-Ischial Vacuum Socket. This study aimed to quantify the rectifications required to fit the Northwestern University Flexible Sub-Ischial Vacuum Socket to teach the technique to prosthetists as well as provide a computer-aided design-computer-aided manufacturing option. Development project. A program was used to align scans of unrectified and rectified negative molds and calculate shape change as a result of rectification. Averaged rectifications were used to create a socket template, which was shared with a central fabrication facility engaged in provision of Northwestern University Flexible Sub-Ischial Vacuum Sockets to early clinical adopters. Feedback regarding quality of fitting was obtained. Rectification maps created from 30 cast pairs of successfully fit Northwestern University Flexible Sub-Ischial Vacuum Sockets confirmed that material was primarily removed from the positive mold in the proximal-lateral and posterior regions. The template was used to fabricate check sockets for 15 persons with transfemoral amputation. Feedback suggested that the template provided a reasonable initial fit with only minor adjustments. Rectification maps and template were used to facilitate teaching and central fabrication of the Northwestern University Flexible Sub-Ischial Vacuum Socket. Minor issues with quality of initial fit achieved with the template may be due to inability to adjust the template to patient characteristics (e.g. tissue type, limb shape) and/or the degree to which it represented a fully mature version of the technique. Clinical relevance Rectification maps help communicate an important step in the fabrication of the Northwestern University Flexible Sub-Ischial Vacuum

Facile synthesis of cyclopentenone B1- and L1-type Phytoprostanes

NASA Astrophysics Data System (ADS)

Guy, Alexandre; Flanagan, Seamus; Durand, Thierry; Oger, Camille; Galano, Jean-Marie

2015-07-01

Phytoprostanes (PhytoPs) represent non-enzymatic metabolites of α-linolenic acid (ALA), the essential omega-3 polyunsaturated fatty acid (PUFA) derived from plants. PhytoPs are present in the plant kingdom and represent endogenous mediators capable of protecting cells from oxidative stress damages in plants. Recently, it was found that such metabolites are present in cooking oil in high quantities, and also that B1-PhytoPs protect immature neurons from oxidant injury and promote differentiation of oligodendrocyte progenitors through PPAR-γ activation. We report a novel and facile synthesis of natural 2,3-substituted cyclopentenone PhytoPs, 16-B1-PhytoP and 9-L1-PhytoP. Our strategy is based on reductive alkylation at the 2-position of 1,3-cyclopentanedione using a recent protocol developed by Ramachary et al., and on a cross-coupling metathesis to access conjugate dienone system. In conclusion, this strategy permitted access to B1- and L1-PhytoPs in a relative short sequence process, and afford the possibility to easily develop analogs of PhytoPs.

Facile synthesis of cyclopentenone B1- and L1-type phytoprostanes

PubMed Central

Guy, Alexandre; Flanagan, Séamus; Durand, Thierry; Oger, Camille; Galano, Jean-Marie

2015-01-01

Phytoprostanes (PhytoPs) represent non-enzymatic metabolites of α-linolenic acid (ALA), the essential omega-3 polyunsaturated fatty acid (PUFA) derived from plants. PhytoPs are present in the plant kingdom and represent endogenous mediators capable of protecting cells from oxidative stress damages in plants. Recently, it was found that such metabolites are present in cooking oil in high quantities, and also that B1-PhytoPs protect immature neurons from oxidant injury and promote differentiation of oligodendrocyte progenitors through PPAR-γ activation. We report a novel and facile synthesis of natural 2,3-substituted cyclopentenone PhytoPs, 16-B1-PhytoP, and 9-L1-PhytoP. Our strategy is based on reductive alkylation at the 2-position of 1,3-cyclopentanedione using a recent protocol developed by Ramachary et al. and on a cross-coupling metathesis to access conjugate dienone system. In conclusion, this strategy permitted access to B1- and L1-PhytoPs in a relative short sequence process, and afford the possibility to easily develop analogs of PhytoPs. PMID:26217659

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.

First High-Convergence Cryogenic Implosion in a Near-Vacuum Hohlraum

NASA Astrophysics Data System (ADS)

Berzak Hopkins, L. F.; Meezan, N. B.; Le Pape, S.; Divol, L.; Mackinnon, A. J.; Ho, D. D.; Hohenberger, M.; Jones, O. S.; Kyrala, G.; Milovich, J. L.; Pak, A.; Ralph, J. E.; Ross, J. S.; Benedetti, L. R.; Biener, J.; Bionta, R.; Bond, E.; Bradley, D.; Caggiano, J.; Callahan, D.; Cerjan, C.; Church, J.; Clark, D.; Döppner, T.; Dylla-Spears, R.; Eckart, M.; Edgell, D.; Field, J.; Fittinghoff, D. N.; Gatu Johnson, M.; Grim, G.; Guler, N.; Haan, S.; Hamza, A.; Hartouni, E. P.; Hatarik, R.; Herrmann, H. W.; Hinkel, D.; Hoover, D.; Huang, H.; Izumi, N.; Khan, S.; Kozioziemski, B.; Kroll, J.; Ma, T.; MacPhee, A.; McNaney, J.; Merrill, F.; Moody, J.; Nikroo, A.; Patel, P.; Robey, H. F.; Rygg, J. R.; Sater, J.; Sayre, D.; Schneider, M.; Sepke, S.; Stadermann, M.; Stoeffl, W.; Thomas, C.; Town, R. P. J.; Volegov, P. L.; Wild, C.; Wilde, C.; Woerner, E.; Yeamans, C.; Yoxall, B.; Kilkenny, J.; Landen, O. L.; Hsing, W.; Edwards, M. J.

2015-05-01

Recent experiments on the National Ignition Facility [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] demonstrate that utilizing a near-vacuum hohlraum (low pressure gas-filled) is a viable option for high convergence cryogenic deuterium-tritium (DT) layered capsule implosions. This is made possible by using a dense ablator (high-density carbon), which shortens the drive duration needed to achieve high convergence: a measured 40% higher hohlraum efficiency than typical gas-filled hohlraums, which requires less laser energy going into the hohlraum, and an observed better symmetry control than anticipated by standard hydrodynamics simulations. The first series of near-vacuum hohlraum experiments culminated in a 6.8 ns, 1.2 MJ laser pulse driving a 2-shock, high adiabat (α ˜3.5 ) cryogenic DT layered high density carbon capsule. This resulted in one of the best performances so far on the NIF relative to laser energy, with a measured primary neutron yield of 1.8 ×1015 neutrons, with 20% calculated alpha heating at convergence ˜27 × .

First high-convergence cryogenic implosion in a near-vacuum hohlraum

DOE PAGES

Berzak Hopkins, L.  F.; Meezan, N.  B.; Le Pape, S.; ...

2015-04-29

Recent experiments on the National Ignition Facility [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] demonstrate that utilizing a near-vacuum hohlraum (low pressure gas-filled) is a viable option for high convergence cryogenic deuterium-tritium (DT) layered capsule implosions. This is made possible by using a dense ablator (high-density carbon), which shortens the drive duration needed to achieve high convergence: a measured 40% higher hohlraum efficiency than typical gas-filled hohlraums, which requires less laser energy going into the hohlraum, and an observed better symmetry control than anticipated by standard hydrodynamics simulations. The first series of near-vacuum hohlraum experiments culminated inmore » a 6.8 ns, 1.2 MJ laser pulse driving a 2-shock, high adiabat (α ~ 3.5) cryogenic DT layered high density carbon capsule. This resulted in one of the best performances so far on the NIF relative to laser energy, with a measured primary neutron yield of 1.8 X 10¹⁵ neutrons, with 20% calculated alpha heating at convergence ~27X.« less

40 CFR Table 31 to Subpart G of... - Typical Number of Vacuum Breakers, NF6 and Roof Drains, a NF7

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Typical Number of Vacuum Breakers, NF6..., and Wastewater Pt. 63, Subpt. G, Table 31 Table 31 to Subpart G of Part 63—Typical Number of Vacuum Breakers, NF6 and Roof Drains, a NF7 Tank diameter D (feet) b No. of vacuum breakers, NF6 Pontoon roof...

Development of a Control System for the Teat-End Vacuum in Individual Quarter Milking Systems

PubMed Central

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

Investigation of Dielectric Breakdown Characteristics for Double-break Vacuum Interrupter and Dielectric Breakdown Probability Distribution in Vacuum Interrupter

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

DOEpatents

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.

Astronaut Charles Conrad poses in shower facility in crew quarters

NASA Technical Reports Server (NTRS)

1973-01-01

Astronaut Charles Conrad Jr., Skylab 2 commander, smiles for the camera after a hot bath in the shower facility in the crew quarters of the Orbital Workshop of the Skylab 2 space station cluster in Earth orbit. In deploying the shower facility the shower curtain is pulled up from the floor and attached to the ceiling. The water comes through a push-button shower head attached to a flexible hose. Water is drawn off by a vacuum system.

Technicians Manufacture a Nozzle for the Kiwi B-1-B Engine

NASA Image and Video Library

1964-05-21

Technicians manufacture a nozzle for the Kiwi B-1-B nuclear rocket engine in the Fabrication Shop’s vacuum oven at the National Aeronautics and Space Administration (NASA) Lewis Research Center. The Nuclear Engine for Rocket Vehicle Applications (NERVA) was a joint NASA and Atomic Energy Commission (AEC) endeavor to develop a nuclear-powered rocket for both long-range missions to Mars and as a possible upper-stage for the Apollo Program. The early portion of the program consisted of basic reactor and fuel system research. This was followed by a series of Kiwi reactors built to test basic nuclear rocket principles in a non-flying nuclear engine. The next phase, NERVA, would create an entire flyable engine. The final phase of the program, called Reactor-In-Flight-Test, would be an actual launch test. The AEC was responsible for designing the nuclear reactor and overall engine. NASA Lewis was responsible for developing the liquid-hydrogen fuel system. The turbopump, which pumped the fuels from the storage tanks to the engine, was the primary tool for restarting the engine. The NERVA had to be able to restart in space on its own using a safe preprogrammed startup system. Lewis researchers endeavored to design and test this system. This non-nuclear Kiwi engine, seen here, was being prepared for tests at Lewis’ High Energy Rocket Engine Research Facility (B-1) located at Plum Brook Station. The tests were designed to start an unfueled Kiwi B-1-B reactor and its Aerojet Mark IX turbopump without any external power.

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.

Vacuum Technology Considerations For Mass Metrology

PubMed Central

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.

Developing a vacuum cooking equipment prototype to produce strawberry jam and optimization of vacuum cooking conditions.

PubMed

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.

E.C.I.A. Chapter 1, Part B, Institutionalized Facilities Program, 1989-90. OREA Report.

ERIC Educational Resources Information Center

Miller, Ronald C.

This report evaluates a program funded under the Educational Consolidation and Improvement Act (ECIA), Chapter 1, Part B, in New York (New York). The Program for Neglected and Delinquent Children, District 75/Citywide Institutionalized Facilities Program provides after-school supplementary instruction in prevocational skills, activities of daily…

Symmetry control in subscale near-vacuum hohlraums

NASA Astrophysics Data System (ADS)

Turnbull, D.; Berzak Hopkins, L. F.; Le Pape, S.; Divol, L.; Meezan, N.; Landen, O. L.; Ho, D. D.; Mackinnon, A.; Zylstra, A. B.; Rinderknecht, H. G.; Sio, H.; Petrasso, R. D.; Ross, J. S.; Khan, S.; Pak, A.; Dewald, E. L.; Callahan, D. A.; Hurricane, O.; Hsing, W. W.; Edwards, M. J.

2016-05-01

Controlling the symmetry of indirect-drive inertial confinement fusion implosions remains a key challenge. Increasing the ratio of the hohlraum diameter to the capsule diameter (case-to-capsule ratio, or CCR) facilitates symmetry tuning. By varying the balance of energy between the inner and outer cones as well as the incident laser pulse length, we demonstrate the ability to tune from oblate, through round, to prolate at a CCR of 3.2 in near-vacuum hohlraums at the National Ignition Facility, developing empirical playbooks along the way for cone fraction sensitivity of various laser pulse epochs. Radiation-hydrodynamic simulations with enhanced inner beam propagation reproduce most experimental observables, including hot spot shape, for a majority of implosions. Specular reflections are used to diagnose the limits of inner beam propagation as a function of pulse length.

Protoflight photovoltaic power module system-level tests in the space power facility

NASA Technical Reports Server (NTRS)

Rivera, Juan C.; Kirch, Luke A.

1989-01-01

Work Package Four, which includes the NASA-Lewis and Rocketdyne, has selected an approach for the Space Station Freedom Photovoltaic (PV) Power Module flight certification that combines system level qualification and acceptance testing in the thermal vacuum environment: The protoflight vehicle approach. This approach maximizes ground test verification to assure system level performance and to minimize risk of on-orbit failures. The preliminary plans for system level thermal vacuum environmental testing of the protoflight PV Power Module in the NASA-Lewis Space Power Facility (SPF), are addressed. Details of the facility modifications to refurbish SPF, after 13 years of downtime, are briefly discussed. The results of an evaluation of the effectiveness of system level environmental testing in screening out incipient part and workmanship defects and unique failure modes are discussed. Preliminary test objectives, test hardware configurations, test support equipment, and operations are presented.

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.

Working in a Vacuum

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)…

High School E.C.I.A. Chapter 1, Part B, Institutionalized Facilities Program 1989-90. State Report. OREA Report.

ERIC Educational Resources Information Center

New York City Board of Education, Brooklyn, NY. Office of Research, Evaluation, and Assessment.

This report describes and evaluates high school programs funded under Chapter 1, Part B, of the Education Consolidation and Improvement Act (ECIA) and administered by the Institutionalized Facilities Program of the New York City Public Schools in 1989-90. The program is designed to address the educational needs of students in facilities for…

Nonperturbative vacuum polarization effects in two-dimensional supercritical Dirac-Coulomb system I. Vacuum charge density

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.

The Lewis Research Center geomagnetic substorm simulation facility

NASA Technical Reports Server (NTRS)

Berkopec, F. D.; Stevens, N. J.; Sturman, J. C.

1977-01-01

A simulation facility was established to determine the response of typical spacecraft materials to the geomagnetic substorm environment and to evaluate instrumentation that will be used to monitor spacecraft system response to this environment. Space environment conditions simulated include the thermal-vacuum conditions of space, solar simulation, geomagnetic substorm electron fluxes and energies, and the low energy plasma environment. Measurements for spacecraft material tests include sample currents, sample surface potentials, and the cumulative number of discharges. Discharge transients are measured by means of current probes and oscilloscopes and are verified by a photomultiplier. Details of this facility and typical operating procedures are presented.

Nonperturbative vacuum polarization effects in two-dimensional supercritical Dirac-Coulomb system II. Vacuum energy

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.

Seeds in space experiment. [long duration exposure facility

NASA Technical Reports Server (NTRS)

Alston, Jim A.

1992-01-01

Two million seeds of 120 different varieties representing 106 species, 97 genera, and 55 plant families were flown aboard the Long Duration Exposure Facility (LDEF). The seeds were housed in one sealed canister and in two small vented canisters. After being returned to earth, the seeds were germinated and the germination rates and development of the resulting plants were compared to the performance of the control seeds that stayed in the Park Seed's seed storage facility. There was a better survival rate in the sealed canister in space than at the storage facility at Park Seed. At least some of the seeds in each of the vented canisters survived the exposure to vacuum for almost six years. The number of observed apparent mutations was very low.

Quantum vacuum noise in physics and cosmology.

PubMed

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

Effects of vigorous mixing of blood vacuum tubes on laboratory test results.

PubMed

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Gelati, Matteo; Volanski, Waldemar; Boritiza, Katia Cristina; Picheth, Geraldo; Guidi, Gian Cesare

2013-02-01

To evaluate the effect of tubes mixing (gentle vs. vigorous) on diagnostic blood specimens collected in vacuum tube systems by venipuncture. Blood was collected for routine coagulation, immunochemistry and hematological testing from one hundred volunteers into six vacuum tubes: two 3.6 mL vacuum tubes containing 0.4 mL of buffered sodium citrate (9NC) 0.109 mol/L: 3.2 W/V%; two 3.5 mL vacuum tubes with clot activator and gel separator; and two 3.0 mL vacuum tubes containing 5.9 mg K(2)EDTA (Terumo Europe, Belgium). Immediately after the venipuncture all vacuum tubes (each of one additive type) were processed through two different procedures: i) Standard: blood specimens in K(2)EDTA- or sodium citrate-vacuum tubes were gently inverted five times whereas the specimens in tubes with clot activator and gel separator were gently inverted ten times, as recommended by the manufacturer; ii) Vigorous mix: all blood specimens were shaken up vigorously during 3-5s independently of the additive type inside the tubes. The significance of the differences between samples was assessed by Student's t-test or Wilcoxon ranked-pairs test after checking for normality. The level of statistical significance was set at P<0.05. No significant difference (P<0.05) was detected between the procedures for all tested parameters. Surprisingly only a visual alteration (presence of foam on the top) was shown by all the tubes mixed vigorously before centrifugation (Fig. 1 A, B and C). Moreover the serum tubes from vigorous mixing procedure shows a "blood ring" on the tube top after stopper removal (Fig. 1 D). Our results drop out a paradigm suggesting that the incorrect primary blood tubes mixing promotes laboratory variability. We suggest that similar evaluation should be done using other brands of vacuum tubes by each laboratory manager. Copyright © 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Vacuum phonon tunneling.

PubMed

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.

Atmospheres and spectra of strongly magnetized neutron stars - II. The effect of vacuum polarization

NASA Astrophysics Data System (ADS)

Ho, Wynn C. G.; Lai, Dong

2003-01-01

We study the effect of vacuum polarization on the atmosphere structure and radiation spectra of neutron stars with surface magnetic fields B= 1014-1015 G, as appropriate for magnetars. Vacuum polarization modifies the dielectric property of the medium and gives rise to a resonance feature in the opacity; this feature is narrow and occurs at a photon energy that depends on the plasma density. Vacuum polarization can also induce resonant conversion of photon modes via a mechanism analogous to the Mikheyev-Smirnov-Wolfenstein (MSW) mechanism for neutrino oscillation. We construct atmosphere models in radiative equilibrium with an effective temperature of a few ×106 K by solving the full radiative transfer equations for both polarization modes in a fully ionized hydrogen plasma. We discuss the subtleties in treating the vacuum polarization effects in the atmosphere models and present approximate solutions to the radiative transfer problem which bracket the true answer. We show from both analytic considerations and numerical calculations that vacuum polarization produces a broad depression in the X-ray flux at high energies (a few keV <~E<~ a few tens of keV) as compared to models without vacuum polarization; this arises from the density dependence of the vacuum resonance feature and the large density gradient present in the atmosphere. Thus the vacuum polarization effect softens the high-energy tail of the thermal spectrum, although the atmospheric emission is still harder than the blackbody spectrum because of the non-grey opacities. We also show that the depression of continuum flux strongly suppresses the equivalent width of the ion cyclotron line and therefore makes the line more difficult to observe.

Cold cathode vacuum gauging system

DOEpatents

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.

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

DOEpatents

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)

Facile synthesis of the Ti3+ self-doped TiO2-graphene nanosheet composites with enhanced photocatalysis.

PubMed

Qiu, Bocheng; Zhou, Yi; Ma, Yunfei; Yang, Xiaolong; Sheng, Weiqin; Xing, Mingyang; Zhang, Jinlong

2015-02-26

This study developed a facile approach for preparing Ti(3+) self-doped TiO2-graphene photocatalyst by a one-step vacuum activation technology involved a relative lower temperature, which could be activated by the visible light owing to the synergistic effect among Ti(3+) doping, some new intersurface bonds generation and graphene oxide reduction. Compared with the traditional methods, the vacuum activation involves a low temperature and low-costing, which can achieve the reduction of GO, the self doping of Ti(3+) in TiO2 and the loading of TiO2 nanoparticles on GR surface at the same time. These resulting TiO2-graphene composites show the high photodegradation rate of MO, high hydrogen evolution activity and excellent IPCE in the visible light irradiation. The facile vacuum activation method can provide an effective and practical approach to improve the performance of TiO2-graphene and other metal oxides-graphene towards their practical photocatalytic applications.

Facile synthesis of the Ti3+ self-doped TiO2-graphene nanosheet composites with enhanced photocatalysis

NASA Astrophysics Data System (ADS)

Qiu, Bocheng; Zhou, Yi; Ma, Yunfei; Yang, Xiaolong; Sheng, Weiqin; Xing, Mingyang; Zhang, Jinlong

2015-02-01

This study developed a facile approach for preparing Ti3+ self-doped TiO2-graphene photocatalyst by a one-step vacuum activation technology involved a relative lower temperature, which could be activated by the visible light owing to the synergistic effect among Ti3+ doping, some new intersurface bonds generation and graphene oxide reduction. Compared with the traditional methods, the vacuum activation involves a low temperature and low-costing, which can achieve the reduction of GO, the self doping of Ti3+ in TiO2 and the loading of TiO2 nanoparticles on GR surface at the same time. These resulting TiO2-graphene composites show the high photodegradation rate of MO, high hydrogen evolution activity and excellent IPCE in the visible light irradiation. The facile vacuum activation method can provide an effective and practical approach to improve the performance of TiO2-graphene and other metal oxides-graphene towards their practical photocatalytic applications.

Effect of Air and Vacuum Storage on the Tensile Properties of X-Ray Exposed Aluminized-FEP

NASA Technical Reports Server (NTRS)

deGroh, Kim K.; Gummow, Jonathan D.

2000-01-01

Metallized Teflon(Registered Trademark) FEP (fluorinated ethylene propylene), a common spacecraft thermal control material, from the exterior layer of the Hubble Space Telescope (HST) has become embrittled and suffers from extensive cracking. Teflon samples retrieved during Hubble servicing missions and from the Long Duration Exposure Facility (LDEF) indicate that there may be continued degradation in tensile properties over time. An investigation has been conducted to evaluate the effect of air and vacuum storage on the mechanical properties of x-ray exposed FEP. Aluminized-FEP (Al-FEP) tensile samples were irradiated with 15.3 kV Cu x-rays and stored in air or under vacuum for various time periods. Tensile data indicate that samples stored in air display larger decreases in tensile properties than for samples stored under vacuum. Air-stored samples developed a hazy appearance, which corresponded to a roughening of the aluminized surface. Optical property changes were also characterized. These findings indicate that air exposure plays a role in the degradation of irradiated FEP, therefore proper sample handling and storage is necessary with materials retrieved from space.

Contamination Sources Effects Analysis (CSEA) - A Tool to Balance Cost/Schedule While Managing Facility Availability

NASA Technical Reports Server (NTRS)

Wilcox, Margaret

2008-01-01

A CSEA is similar to a Failure Modes Effects Analysis (FMEA). A CSEA tracks risk, deterrence, and occurrence of sources of contamination and their mitigation plans. Documentation is provided spanning mechanical and electrical assembly, precision cleaning, thermal vacuum bake-out, and thermal vacuum testing. These facilities all may play a role in contamination budgeting and reduction ultimately affecting test and flight. With a CSEA, visibility can be given to availability of these facilities, test sequencing and trade-offs. A cross-functional team including specialty engineering, contamination control, electrostatic dissipation, manufacturing, testing, and material engineering participate in an exercise that identifies contaminants and minimizes the complexity of scheduling these facilities considering their volatile schedules. Care can be taken in an efficient manner to insure correct cleaning processes are employed. The result is reduction in cycle time ("schedule hits"), reduced cost due to rework, reduced risk and improved communication and quality while achieving adherence to the Contamination Control Plan.

High Current Density Cathodes for Future Vacuum Electronics Applications

DTIC Science & Technology

2008-05-30

Tube - device for generating high levels of RF power DARPA Defense Advanced Research Agency PBG Photonic band gap W- Band 75-111 GHz dB Decibels GHz...Extended interaction klystron 1. Introduction All RF vacuum electron sources require a high quality electron beam for efficient operation. Research on...with long life. Pres- ently, only thermionic dispenser cathodes are practical for high power RF sources. Typical thermi- onic cathodes consists of a

Vacuum enhanced cutaneous biopsy instrument

DOEpatents

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.

Vacuum Magnetic Field Mapping of the Compact Toroidal Hybrid (CTH)

NASA Astrophysics Data System (ADS)

Peterson, J. T.; Hanson, J.; Hartwell, G. J.; Knowlton, S. F.; Montgomery, C.; Munoz, J.

2007-11-01

Vacuum magnetic field mapping experiments are performed on the CTH torsatron with a movable electron gun and phosphor-coated screen or movable wand at two different toroidal locations. These experiments compare the experimentally measured magnetic configuration produced by the as-built coil set, to the magnetic configuration simulated with the IFT Biot-Savart code using the measured coil set parameters. Efforts to minimize differences between the experimentally measured location of the magnetic axis and its predicted value utilizing a Singular Value Decomposition (SVD) process result in small modifications of the helical coil winding law used to model the vacuum magnetic field geometry of CTH. Because these studies are performed at relatively low fields B = 0.01 - 0.05 T, a uniform ambient magnetic field is included in the minimization procedure.

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

Vacuum Ultraviolet Absorption Measurements of Atomic Oxygen in a Shock Tube

NASA Technical Reports Server (NTRS)

Meyer, Scott Andrew

1995-01-01

The absorption of vacuum ultraviolet light by atomic oxygen has been measured in the Electric Arc-driven Shock Tube (EAST) Facility at NASA-Ames Research Center. This investigation demonstrates the instrumentation required to determine atomic oxygen concentrations from absorption measurements in impulse facilities. A shock wave dissociates molecular oxygen, producing a high temperature sample of atomic oxygen in the shock tube. A probe beam is generated with a Raman-shifted ArF excimer laser. By suitable tuning of the laser, absorption is measured over a range of wavelengths in the region of the atomic line at 130.49 nm. The line shape function is determined from measurements at atomic oxygen densities of 3 x 10(exp 17) and 9 x 10(exp 17)/cu cm. The broadening coefficient for resonance interactions is deduced from this data, and this value is in accord with available theoretical models.

Vacuum Ultraviolet Absorption Measurements of Atomic Oxygen in a Shock Tube

NASA Technical Reports Server (NTRS)

Meyer, Scott Andrew

1995-01-01

The absorption of vacuum ultraviolet light by atomic oxygen has been measured in the Electric Arc-driven Shock Tube (EAST) Facility at NASA-Ames Research Center. This investigation demonstrates the instrumentation required to determine atomic oxygen concentrations from absorption measurements in impulse facilities. A shock wave dissociates molecular oxygen, producing a high temperature sample of atomic oxygen in the shock tube. A probe beam is generated with a Raman-shifted ArF excimer laser. By suitable tuning of the laser, absorption is measured over a range of wavelengths in the region of the atomic line at 130.49 nm. The line shape function is determined from measurements at atomic oxygen densities of 3x10(exp 17) and 9x10(exp 17) cm(exp -3). The broadening coefficient for resonance interactions is deduced from this data, and this value is in accord with available theoretical models.

Vacuum Ultraviolet Absorption Measurements of Atomic Oxygen in a Shock Tube

NASA Technical Reports Server (NTRS)

Meyer, Scott Andrew

1995-01-01

The absorption of vacuum ultraviolet light by atomic oxygen has been measured in the Electric Arc-driven Shock Tube (EAST) Facility at NASA-Ames Research Center. This investigation demonstrates the instrumentation required to determine atomic oxygen concentrations from absorption measurements in impulse facilities. A shock wave dissociates molecular oxygen, producing a high temperature sample of atomic oxygen in the shock tube. A probe beam is generated with a Raman-shifted ArF excimer laser. By suitable tuning of the laser, absorption is measured over a range of wavelengths in the region of the atomic line at 130.49 nm. The line shape function is determined from measurements at atomic oxygen densities of 3 x 10(exp 17) and 9 x 10(exp 17) cm(exp -3). The broadening coefficient for resonance interactions is deduced from this data, and this value is in accord with available theoretical models.

Characteristics and performance of a superconducting bumpy-torus magnet facility for plasma research

NASA Technical Reports Server (NTRS)

Roth, J. R.; Holmes, A. D.; Keller, T. A.; Krawczonek, W. M.

1973-01-01

The NASA Lewis bumpy-torus facility consists of 12 superconducting coils, each 19 cm i.d. and capable of 3.0 T on its axis. The coils are equally spaced around a toroidal array with a major diameter of 1.52 m; they are mounted with the major axis of the torus vertical in a single vacuum tank 2.6 m in diameter. Tests of the facility mapped out its magnetic, cryogenic, vacuum, mechanical, and electrical performance. The design value of the maximum magnetic field on the magnetic axis, 3.0 T, was reached and exceeded. A maximum magnetic field of 3.23 T was held for a period of 60 minutes. When the coils were charged to a maximum magnetic field of 3.35 T, the coil system went normal without apparent damage or degradation of performance.

TOP 01-1-011B Vehicle Test Facilities at Aberdeen Test Center and Yuma Test Center

DTIC Science & Technology

2017-12-12

TYPE Final 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Test Operations Procedure (TOP) 01-1-011B Vehicle Test Facilities at Aberdeen... Test Center and Yuma Test Center 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHORS 5d. PROJECT NUMBER 5e... Test Center 400 Colleran Road Aberdeen Proving Ground, MD 21005-5059 U.S. Army Yuma Proving Ground Yuma Test Center 301 C. Street Yuma, AZ

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.

Symmetry control in subscale near-vacuum hohlraums

DOE PAGES

Turnbull, D.; Berzak Hopkins, L. F.; Le Pape, S.; ...

2016-05-18

Controlling the symmetry of indirect-drive inertial confinement fusion implosions remains a key challenge. Increasing the ratio of the hohlraum diameter to the capsule diameter (case-to-capsule ratio, or CCR) facilitates symmetry tuning. By varying the balance of energy between the inner and outer cones as well as the incident laser pulse length, we demonstrate the ability to tune from oblate, through round, to prolate at a CCR of 3.2 in near-vacuum hohlraums at the National Ignition Facility, developing empirical playbooks along the way for cone fraction sensitivity of various laser pulse epochs. Radiation-hydrodynamic simulations with enhanced inner beam propagation reproduce mostmore » experimental observables, including hot spot shape, for a majority of implosions. In conclusion, specular reflections are used to diagnose the limits of inner beam propagation as a function of pulse length.« less

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.

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.

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].

PubMed

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.

Evaluation of a Prototype Hybrid Vacuum Pump to Provide Vacuum-Assisted Suspension for Above-Knee Prostheses

PubMed Central

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.

TEMPUS: A facility for containerless electromagnetic processing onboard spacelab

NASA Technical Reports Server (NTRS)

Lenski, H.; Willnecker, R.

1990-01-01

The electromagnetic containerless processing facility TEMPUS was recently assigned for a flight on the IML-2 mission. In comparison to the TEMPUS facility already flown on a sounding rocket, several improvements had to be implemented. These are in particular related to: safety; resource management; and the possibility to process different samples with different requirements in one mission. The basic design of this facility as well as the expected processing capabilities are presented. Two operational aspects turned out to strongly influence the facility design: control of the sample motion (first experimental results indicate that crew or ground interaction will be necessary to minimize residual sample motions during processing); and exchange of RF-coils (during processing in vacuum, evaporated sample materials will condense at the cold surface and may force a coil exchange, when a critical thickness is exceeded).

Diffraction-limited storage-ring vacuum technology

PubMed Central

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

NASA Image and Video Library

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.

Cryogenic Test Capability at Marshall Space Flight Center's X-ray Cryogenic Test Facility

NASA Technical Reports Server (NTRS)

Kegley, Jeffrey; Baker, Mark; Carpenter, Jay; Eng, Ron; Haight, Harlan; Hogue, William; McCracken, Jeff; Siler, Richard; Wright, Ernie

2006-01-01

Marshall Space Flight Center's X-ray & Cryogenic Test Facility (XRCF) has been performing sub-liquid nitrogen temperature testing since 1999. Optical wavefront measurement, thermal structural deformation, mechanism functional & calibration, and simple cryo-conditioning tests have been completed. Recent modifications have been made to the facility in support of the James Webb Space Telescope (JWST) program. The chamber's payload envelope and the facility s refrigeration capacity have both been increased. Modifications have also been made to the optical instrumentation area improving access for both the installation and operation of optical instrumentation outside the vacuum chamber. The facility's capabilities, configuration, and performance data will be presented.

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…

Shipboard Facilities Maintenance and Manpower Utilization: Problem and Approach

DTIC Science & Technology

1975-11-01

sweeping, butting, polishing, lacquering, stenciling, vacuuming and shampooing , garbage disposal and trash removal, and all manner of sanitary and...spaces, passageways, heads and showers, crew lounge, mess decks, exterior deck and ship sides, and all office spaces; and limited facilities...maintenance in all passageways, heads , mess decks, office spaces, and berthing areas. They will also per- form sanitization and exterior deck and

Modeling Analysis for NASA GRC Vacuum Facility 5 Upgrade

NASA Technical Reports Server (NTRS)

Yim, J. T.; Herman, D. A.; Burt, J. M.

2013-01-01

A model of the VF5 test facility at NASA Glenn Research Center was developed using the direct simulation Monte Carlo Hypersonic Aerothermodynamics Particle (HAP) code. The model results were compared to several cold flow and thruster hot fire cases. The main uncertainty in the model is the determination of the effective sticking coefficient -- which sets the pumping effectiveness of the cryopanels and oil diffusion pumps including baffle transmission. An effective sticking coefficient of 0.25 was found to provide generally good agreement with the experimental chamber pressure data. The model, which assumes a cold diffuse inflow, also fared satisfactorily in predicting the pressure distribution during thruster operation. The model was used to assess other chamber configurations to improve the local effective pumping speed near the thruster. A new configuration of the existing cryopumps is found to show more than 2x improvement over the current baseline configuration.

Planetary and Space Simulation Facilities PSI at DLR for Astrobiology

NASA Astrophysics Data System (ADS)

Rabbow, E.; Rettberg, P.; Panitz, C.; Reitz, G.

2008-09-01

Ground based experiments, conducted in the controlled planetary and space environment simulation facilities PSI at DLR, are used to investigate astrobiological questions and to complement the corresponding experiments in LEO, for example on free flying satellites or on space exposure platforms on the ISS. In-orbit exposure facilities can only accommodate a limited number of experiments for exposure to space parameters like high vacuum, intense radiation of galactic and solar origin and microgravity, sometimes also technically adapted to simulate extraterrestrial planetary conditions like those on Mars. Ground based experiments in carefully equipped and monitored simulation facilities allow the investigation of the effects of simulated single environmental parameters and selected combinations on a much wider variety of samples. In PSI at DLR, international science consortia performed astrobiological investigations and space experiment preparations, exposing organic compounds and a wide range of microorganisms, reaching from bacterial spores to complex microbial communities, lichens and even animals like tardigrades to simulated planetary or space environment parameters in pursuit of exobiological questions on the resistance to extreme environments and the origin and distribution of life. The Planetary and Space Simulation Facilities PSI of the Institute of Aerospace Medicine at DLR in Köln, Germany, providing high vacuum of controlled residual composition, ionizing radiation of a X-ray tube, polychromatic UV radiation in the range of 170-400 nm, VIS and IR or individual monochromatic UV wavelengths, and temperature regulation from -20°C to +80°C at the sample size individually or in selected combinations in 9 modular facilities of varying sizes are presented with selected experiments performed within.

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.

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)

Near-vacuum hohlraums for driving fusion implosions with high density carbon ablatorsa)

NASA Astrophysics Data System (ADS)

Berzak Hopkins, L. F.; Le Pape, S.; Divol, L.; Meezan, N. B.; Mackinnon, A. J.; Ho, D. D.; Jones, O. S.; Khan, S.; Milovich, J. L.; Ross, J. S.; Amendt, P.; Casey, D.; Celliers, P. M.; Pak, A.; Peterson, J. L.; Ralph, J.; Rygg, J. R.

2015-05-01

Recent experiments at the National Ignition Facility [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] have explored driving high-density carbon ablators with near-vacuum hohlraums, which use a minimal amount of helium gas fill. These hohlraums show improved efficiency relative to conventional gas-filled hohlraums in terms of minimal backscatter, minimal generation of suprathermal electrons, and increased hohlraum-capsule coupling. Given these advantages, near-vacuum hohlraums are a promising choice for pursuing high neutron yield implosions. Long pulse symmetry control, though, remains a challenge, as the hohlraum volume fills with material. Two mitigation methodologies have been explored, dynamic beam phasing and increased case-to-capsule ratio (larger hohlraum size relative to capsule). Unexpectedly, experiments have demonstrated that the inner laser beam propagation is better than predicted by nominal simulations, and an enhanced beam propagation model is required to match measured hot spot symmetry. Ongoing work is focused on developing a physical model which captures this enhanced propagation and on utilizing the enhanced propagation to drive longer laser pulses than originally predicted in order to reach alpha-heating dominated neutron yields.

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.

Preparation of a Frozen Regolith Simulant Bed for ISRU Component Testing in a Vacuum Chamber

NASA Technical Reports Server (NTRS)

Klenhenz, Julie; Linne, Diane

2013-01-01

In-Situ Resource Utilization (ISRU) systems and components have undergone extensive laboratory and field tests to expose hardware to relevant soil environments. The next step is to combine these soil environments with relevant pressure and temperature conditions. Previous testing has demonstrated how to incorporate large bins of unconsolidated lunar regolith into sufficiently sized vacuum chambers. In order to create appropriate depth dependent soil characteristics that are needed to test drilling operations for the lunar surface, the regolith simulant bed must by properly compacted and frozen. While small cryogenic simulant beds have been created for laboratory tests, this scale effort will allow testing of a full 1m drill which has been developed for a potential lunar prospector mission. Compacted bulk densities were measured at various moisture contents for GRC-3 and Chenobi regolith simulants. Vibrational compaction methods were compared with the previously used hammer compaction, or "Proctor", method. All testing was done per ASTM standard methods. A full 6.13 m3 simulant bed with 6 percent moisture by weight was prepared, compacted in layers, and frozen in a commercial freezer. Temperature and desiccation data was collected to determine logistics for preparation and transport of the simulant bed for thermal vacuum testing. Once in the vacuum facility, the simulant bed will be cryogenically frozen with liquid nitrogen. These cryogenic vacuum tests are underway, but results will not be included in this manuscript.

75 FR 76019 - Compliance Policy Guide Sec. 390.500 Definition of “High-Voltage Vacuum Switch”-21 CFR 1002.61(a...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-07

...] Compliance Policy Guide Sec. 390.500 Definition of ``High-Voltage Vacuum Switch''--21 CFR 1002.61(a)(3) and... Sec. 390.500 Definition of ``High-Voltage Vacuum Switch''--21 CFR 1002.61(a)(3) and (b)(2) (CPG Sec.... 2010-30677 Filed 12-6-10; 8:45 am] BILLING CODE 4160-01-P ...

Vacuum Levels Needed to Simulate Internal Fatigue Crack Growth in Titanium Alloys and Nickel-base Superalloys: Thermodynamic Considerations

DTIC Science & Technology

2012-03-01

AFRL-RX-WP-TP-2012-0250 VACUUM LEVELS NEEDED TO SIMULATE INTERNAL FATIGUE CRACK GROWTH IN TITANIUM ALLOYS AND NICKEL - BASE SUPERALLOYS...TITANIUM ALLOYS AND NICKEL - BASE SUPERALLOYS: THERMODYNAMIC CONSIDERATIONS (PREPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM...surface growth in Ti- alloys and Ni - base superalloys. Even with the highest vacuum level attained using “state-of-the-art” pumps, it is unclear if

Vacuum chamber-free centrifuge with magnetic bearings.

PubMed

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.

Vacuum deposition and curing of liquid monomers

DOEpatents

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

DOEpatents

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

DOEpatents

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

DOEpatents

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.

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.

Air pollution effects field research facility: 3. UV-B exposure and monitoring system

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

McEvers, J.A.; Hileman, M.S.; Edwards, N.T.

1993-03-01

The Oak Ridge National Laboratory Outdoor UltraViolet-B (UV-B) Exposure and Monitoring Facility was developed in 1980 to provide well-controlled and -monitored exposure of specific terrestrial plant. species to elevated levels of ultraviolet (UV) radiation. The introduction of various anthropogenic agents into the earth`s stratosphere has resulted in a decrease in the volume of ozone (O{sub 3}) present here. The decrease in O{sub 3} has resulted in an increase in the level of UV radiation reaching thee earth`s surface. Of particular interest is the level of UV-B, because it has the most detrimental effect on living tissue. A thorough understanding ofmore » the effects of elevated levels of UV-B on living tissue is critical to the formulation of economic policy regarding production of such agents and alternative strategies. The UV region of interest is referred to as UV-B and corresponds to radiation with a wavelength of 290 to 320 nm. Design, operation, and performance of the automated generation, exposure, and monitoring system are described. The system has proved to be reliable and easy to maintain and operate, and it provides significant flexibility in exposure programs. The system software is described, and detailed listings are provided. The ability to expose plants to controlled set point percentages of UV-B above the ambient level was developed.« less

Vacuum-assisted venous return reduces blood usage.

PubMed

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

Description of Liquid Nitrogen Experimental Test Facility

NASA Technical Reports Server (NTRS)

Jurns, John M.; Jacobs, Richard E.; Saiyed, Naseem H.

1991-01-01

The Liquid Nitrogen Test Facility is a unique test facility for ground-based liquid nitrogen experimentation. The test rig consists of an insulated tank of approximately 12.5 cubic ft in volume, which is supplied with liquid nitrogen from a 300 gal dewar via a vacuum jacketed piping system. The test tank is fitted with pressure and temperature measuring instrumentation, and with two view ports which allow visual observation of test conditions. To demonstrate the capabilities of the facility, the initial test program is briefly described. The objective of the test program is to measure the condensation rate by injecting liquid nitrogen as a subcooled spray into the ullage of a tank 50 percent full of liquid nitrogen at saturated conditions. The condensation rate of the nitrogen vapor on the subcooled spray can be analytically modeled, and results validated and corrected by experimentally measuring the vapor condensation on liquid sprays.

Description of liquid nitrogen experimental test facility

NASA Technical Reports Server (NTRS)

Jurns, J. M.; Jacobs, R. E.; Saiyed, N. H.

1992-01-01

The Liquid Nitrogen Test Facility is a unique test facility for ground-based liquid nitrogen experimentation. The test rig consists of an insulated tank of approximately 12.5 cubic ft in volume, which is supplied with liquid nitrogen from a 300 gal dewar via a vacuum jacketed piping system. The test tank is fitted with pressure and temperature measuring instrumentation, and with two view ports which allow visual observation of test conditions. To demonstrate the capabilities of the facility, the initial test program is briefly described. The objective of the test program is to measure the condensation rate by injecting liquid nitrogen as a subcooled spray into the ullage of a tank 50 percent full of liquid nitrogen at saturated conditions. The condensation rate of the nitrogen vapor on the subcooled spray can be analytically modeled, and results validated and corrected by experimentally measuring the vapor condensation on liquid sprays.

A composite thin vacuum window for the CLAS photon tagger at Jefferson lab

NASA Astrophysics Data System (ADS)

Matthews, S. K.; Crannell, Hall; O'Brien, J. T.; Sober, D. I.

1999-01-01

The construction of a thin vacuum window, currently in use on the CLAS photon tagging system at the Thomas Jefferson National Accelerator Facility, is described. A layer of woven Kevlar cloth supports a much thinner membrane of aluminized Mylar. Notable features of this particular window include its overall length (9.6 m), and the fact that the entire load is supported by the epoxy seal with no mechanical clamping around the edges. Results from a diverse program of materials testing, including a clear dependence of leak rate on relative humidity, are also reported.

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.

Formation of protein sub-visible particles during vacuum degassing of etanercept solutions.

PubMed

Wang, Haibin; Zheng, Hong-Jian; Wang, Zhao; Bai, Hua; Carpenter, John F; Chen, Shuqing; Fang, Wei-Jie

2014-05-01

The main purpose of this manuscript is to describe a phenomenon in which vacuum degassing a reconstituted freeze-dried fusion protein etanercept formulation caused a significant amount of protein sub-visible particles (SbVP). Physical stability of etanercept was monitored by micro-flow imaging (MFI), dynamic light scattering (DLS), size-exclusion high pressure liquid chromatography (SE-HPLC) and far- and near-ultraviolet circular dichroism (far- and near-UV CD). One potential explanation of this phenomenon is that bubble collapses when the vacuum is applied, leads to substantial heat formation, and ultimately free radical formation. Subsequently, the effect of a free-radical scavenger (ascorbic acid, AA) on SbVP formation was also evaluated. Degassing of etanercept solution by applying vacuum caused substantial increase of SbVP, as detected by MFI and DLS. However, traditional techniques such as SE-HPLC could not detect any change. The addition of free-radical scavenger had minimal effect on SbVP formation, therefore the formation of free radicals was probably not the main cause for this effect. Copyright © 2014 Elsevier B.V. All rights reserved.

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.

Radiometric calibration of the vacuum-ultraviolet spectrograph SUMER on the SOHO spacecraft with the B detector.

PubMed

Schühle, U; Curdt, W; Hollandt, J; Feldman, U; Lemaire, P; Wilhelm, K

2000-01-20

The Solar Ultraviolet Measurement of Emitted Radiation (SUMER) vacuum-ultraviolet spectrograph was calibrated in the laboratory before the integration of the instrument on the Solar and Heliospheric Observatory (SOHO) spacecraft in 1995. During the scientific operation of the SOHO it has been possible to track the radiometric calibration of the SUMER spectrograph since March 1996 by a strategy that employs various methods to update the calibration status and improve the coverage of the spectral calibration curve. The results for the A Detector were published previously [Appl. Opt. 36, 6416 (1997)]. During three years of operation in space, the B detector was used for two and one-half years. We describe the characteristics of the B detector and present results of the tracking and refinement of the spectral calibration curves with it. Observations of the spectra of the stars alpha and rho Leonis permit an extrapolation of the calibration curves in the range from 125 to 149.0 nm. Using a solar coronal spectrum observed above the solar disk, we can extrapolate the calibration curves by measuring emission line pairs with well-known intensity ratios. The sensitivity ratio of the two photocathode areas can be obtained by registration of many emission lines in the entire spectral range on both KBr-coated and bare parts of the detector's active surface. The results are found to be consistent with the published calibration performed in the laboratory in the wavelength range from 53 to 124 nm. We can extrapolate the calibration outside this range to 147 nm with a relative uncertainty of ?30% (1varsigma) for wavelengths longer than 125 nm and to 46.5 nm with 50% uncertainty for the short-wavelength range below 53 nm.

DEVELOPMENT AND DEPLOYMENT OF VACUUM SALT DISTILLATION AT THE SAVANNAH RIVER SITE

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

Pierce, R.; Pak, D.; Edwards, T.

2010-10-28

The Savannah River Site has a mission to dissolve fissile materials and disposition them. The primary fissile material is plutonium dioxide (PuO{sub 2}). To support dissolution of these materials, the Savannah River National Laboratory (SRNL) designed and demonstrated a vacuum salt distillation (VSD) apparatus using both representative radioactive samples and non-radioactive simulant materials. Vacuum salt distillation, through the removal of chloride salts, increases the quantity of materials suitable for processing in the site's HB-Line Facility. Small-scale non-radioactive experiments at 900-950 C show that >99.8 wt % of the initial charge of chloride salt distilled from the sample boat with recoverymore » of >99.8 wt % of the ceric oxide (CeO{sub 2}) - the surrogate for PuO{sub 2} - as a non-chloride bearing 'product'. Small-scale radioactive testing in a glovebox demonstrated the removal of sodium chloride (NaCl) and potassium chloride (KCl) from 13 PuO{sub 2} samples. Chloride concentrations were distilled from a starting concentration of 1.8-10.8 wt % to a final concentration <500 mg/kg chloride. Initial testing of a non-radioactive, full-scale production prototype is complete. A designed experiment evaluated the impact of distillation temperature, time at temperature, vacuum, product depth, and presence of a boat cover. Significant effort has been devoted to mechanical considerations to facilitate simplified operation in a glovebox.« less

Vacuum Ultraviolet Radiation Desorption of Molecular Contaminants Deposited on Quartz Crystal Microbalances

NASA Technical Reports Server (NTRS)

Albyn, Keith; Burns, Dewitt

2006-01-01

Recent quartz crystal microbalance measurements made in the Marshall Space Flight Center, Photo-Deposition Facility, for several materials, recorded a significant loss of deposited contaminants when the deposition surface of the microbalance was illuminated by a deuterium lamp. These measurements differ from observations made by other investigators in which the rate of deposition increased significantly when the deposition surface was illuminated with vacuum ultraviolet radiation. These observations suggest that the accelerated deposition of molecular contaminants on optically sensitive surfaces is dependant upon the contaminant being deposited and must be addressed during the materials selection process by common material screening techniques.

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.

Test facilities for high power electric propulsion

NASA Technical Reports Server (NTRS)

Sovey, James S.; Vetrone, Robert H.; Grisnik, Stanley P.; Myers, Roger M.; Parkes, James E.

1991-01-01

Electric propulsion has applications for orbit raising, maneuvering of large space systems, and interplanetary missions. These missions involve propulsion power levels from tenths to tens of megawatts, depending upon the application. General facility requirements for testing high power electric propulsion at the component and thrust systems level are defined. The characteristics and pumping capabilities of many large vacuum chambers in the United States are reviewed and compared with the requirements for high power electric propulsion testing.

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.

2,3-Butanediol recovery from fermentation broth by alcohol precipitation and vacuum distillation.

PubMed

Jeon, Sangjun; Kim, Duk-Ki; Song, Hyohak; Lee, Hee Jong; Park, Sunghoon; Seung, Doyoung; Chang, Yong Keun

2014-04-01

This study presents a new and effective downstream process to recover 2,3-butanediol (2,3-BD) from fermentation broth which is produced by a recombinant Klebsiella pneumoniae strain. The ldhA-deficient K. pneumoniae strain yielded about 90 g/L of 2,3-BD, along with a number of by-products, such as organic acids and alcohols, in a 65 h fed-batch fermentation. The pH-adjusted cell-free fermentation broth was firstly concentrated until 2,3-BD reached around 500 g/L by vacuum evaporation at 50°C and 50 mbar vacuum pressure. The concentrated solution was further treated using light alcohols, including methanol, ethanol, and isopropanol, for the precipitation of organic acids and inorganic salts. Isopropanol showed the highest removal efficiency, in which 92.5% and 99.8% of organic acids and inorganic salts were precipitated, respectively. At a final step, a vacuum distillation process enabled the recovery of 76.2% of the treated 2,3-BD, with 96.1% purity, indicating that fermentatively produced 2,3-BD is effectively recovered by a simple alcohol precipitation and vacuum distillation. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Focal Point Inside the Vacuum Chamber for Solar Thermal Propulsion

NASA Technical Reports Server (NTRS)

1999-01-01

Researchers at the Marshall Space Flight Center (MSFC) have designed, fabricated, and tested the first solar thermal engine, a non-chemical rocket engine that produces lower thrust but has better thrust efficiency than a chemical combustion engine. MSFC turned to solar thermal propulsion in the early 1990s due to its simplicity, safety, low cost, and commonality with other propulsion systems. Solar thermal propulsion works by acquiring and redirecting solar energy to heat a propellant. The 20- by 24-ft heliostat mirror (not shown in this photograph) has dual-axis control that keeps a reflection of the sunlight on an 18-ft diameter concentrator mirror, which then focuses the sunlight to a 4-in focal point inside the vacuum chamber. The focal point has 10 kilowatts of intense solar power. This photograph is a close-up view of a 4-in focal point inside the vacuum chamber at the MSFC Solar Thermal Propulsion Test facility. As part of MSFC's Space Transportation Directorate, the Propulsion Research Center serves as a national resource for research of advanced, revolutionary propulsion technologies. The mission is to move the Nation's capabilities beyond the confines of conventional chemical propulsion into an era of aircraft-like access to Earth orbit, rapid travel throughout the solar system, and exploration of interstellar space.

DKIST facility management system integration

NASA Astrophysics Data System (ADS)

White, Charles R.; Phelps, LeEllen

2016-07-01

The Daniel K. Inouye Solar Telescope (DKIST) Observatory is under construction at Haleakalā, Maui, Hawai'i. When complete, the DKIST will be the largest solar telescope in the world. The Facility Management System (FMS) is a subsystem of the high-level Facility Control System (FCS) and directly controls the Facility Thermal System (FTS). The FMS receives operational mode information from the FCS while making process data available to the FCS and includes hardware and software to integrate and control all aspects of the FTS including the Carousel Cooling System, the Telescope Chamber Environmental Control Systems, and the Temperature Monitoring System. In addition it will integrate the Power Energy Management System and several service systems such as heating, ventilation, and air conditioning (HVAC), the Domestic Water Distribution System, and the Vacuum System. All of these subsystems must operate in coordination to provide the best possible observing conditions and overall building management. Further, the FMS must actively react to varying weather conditions and observational requirements. The physical impact of the facility must not interfere with neighboring installations while operating in a very environmentally and culturally sensitive area. The FMS system will be comprised of five Programmable Automation Controllers (PACs). We present a pre-build overview of the functional plan to integrate all of the FMS subsystems.

Nike Facility Diagnostics and Data Acquisition System

NASA Astrophysics Data System (ADS)

Chan, Yung; Aglitskiy, Yefim; Karasik, Max; Kehne, David; Obenschain, Steve; Oh, Jaechul; Serlin, Victor; Weaver, Jim

2013-10-01

The Nike laser-target facility is a 56-beam krypton fluoride system that can deliver 2 to 3 kJ of laser energy at 248 nm onto targets inside a two meter diameter vacuum chamber. Nike is used to study physics and technology issues related to laser direct-drive ICF fusion, including hydrodynamic and laser-plasma instabilities, material behavior at extreme pressures, and optical and x-ray diagnostics for laser-heated targets. A suite of laser and target diagnostics are fielded on the Nike facility, including high-speed, high-resolution x-ray and visible imaging cameras, spectrometers and photo-detectors. A centrally-controlled, distributed computerized data acquisition system provides robust data management and near real-time analysis feedback capability during target shots. Work supported by DOE/NNSA.

Plasma interpenetration study on the Omega laser facility

NASA Astrophysics Data System (ADS)

Le Pape, Sebastien; Divol, Laurent; Ross, Steven; Wilks, Scott; Amendt, Peter; Berzak Hopkins, Laura; Huser, Gael; Moody, John; MacKinnon, Andy; Meezan, Nathan

2016-10-01

The Near Vacuum Campaign on the National Ignition Facility has sparked an interest on the nature of the gold/carbon interface at high velocity, high electron temperature, low-electron density. Indeed radiation-hydrodynamic simulations have been unable to accurately reproduce the experimental shape of the hot spot resulting from implosion driven in Near Vacuum Holhraum. The experimental data are suggesting that the inner beams are freely propagating to the waist of the hohlraum when simulations predict that a density ridge at the gold/carbon interface blocks the inner beams. The discrepancy between experimental data and simulation might be explained by the fluid description of the plasma interface in a rad-hydro code which is probably not valid in when two plasma at high velocity, high temperature are meeting. To test our assumption, we went to the Omega laser facility to study gold/carbon interface in the relevant regime. Time resolved images of the self-emission as well as Thomson scattering data will be presented. For the first time, a transition from a multifluid to a single fluid is observed as plasmas are interacting. This work was performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344.

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

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

A Heated Tube Facility for Rocket Coolant Channel Research

NASA Technical Reports Server (NTRS)

Green, James M.; Pease, Gary M.; Meyer, Michael L.

1995-01-01

The capabilities of a heated tube facility used for testing rocket engine coolant channels at the NASA Lewis Research Center are presented. The facility uses high current, low voltage power supplies to resistively heat a test section to outer wall temperatures as high as 730 C (1350 F). Liquid or gaseous nitrogen, gaseous helium, or combustible liquids can be used as the test section coolant. The test section is enclosed in a vacuum chamber to minimize heat loss to the surrounding system. Test section geometry, size, and material; coolant properties; and heating levels can be varied to generate heat transfer and coolant performance data bases.

Feasibility of Conducting J-2X Engine Testing at the Glenn Research Center Plum Brook Station B-2 Facility

NASA Technical Reports Server (NTRS)

Schafer, Charles F.; Cheston, Derrick J.; Worlund, Armis L.; Brown, James R.; Hooper, William G.; Monk, Jan C.; Winstead, Thomas W.

2008-01-01

A trade study of the feasibility of conducting J-2X testing in the Glenn Research Center (GRC) Plum Brook Station (PBS) B-2 facility was initiated in May 2006 with results available in October 2006. The Propulsion Test Integration Group (PTIG) led the study with support from Marshall Space Flight Center (MSFC) and Jacobs Sverdrup Engineering. The primary focus of the trade study was on facility design concepts and their capability to satisfy the J-2X altitude simulation test requirements. The propulsion systems tested in the B-2 facility were in the 30,000-pound (30K) thrust class. The J-2X thrust is approximately 10 times larger. Therefore, concepts significantly different from the current configuration are necessary for the diffuser, spray chamber subsystems, and cooling water. Steam exhaust condensation in the spray chamber is judged to be the key risk consideration relative to acceptable spray chamber pressure. Further assessment via computational fluid dynamics (CFD) and other simulation capabilities (e.g. methodology for anchoring predictions with actual test data and subscale testing to support investigation.

Compact vacuum insulation

DOEpatents

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.

Compact vacuum insulation

DOEpatents

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.

Manufacturing Demonstration Facility: Roll-to-Roll Processing

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

Datskos, Panos G; Joshi, Pooran C; List III, Frederick Alyious

This Manufacturing Demonstration Facility (MDF)e roll-to-roll processing effort described in this report provided an excellent opportunity to investigate a number of advanced manufacturing approaches to achieve a path for low cost devices and sensors. Critical to this effort is the ability to deposit thin films at low temperatures using nanomaterials derived from nanofermentation. The overarching goal of this project was to develop roll-to-roll manufacturing processes of thin film deposition on low-cost flexible substrates for electronics and sensor applications. This project utilized ORNL s unique Pulse Thermal Processing (PTP) technologies coupled with non-vacuum low temperature deposition techniques, ORNL s clean roommore » facility, slot dye coating, drop casting, spin coating, screen printing and several other equipment including a Dimatix ink jet printer and a large-scale Kyocera ink jet printer. The roll-to-roll processing project had three main tasks: 1) develop and demonstrate zinc-Zn based opto-electronic sensors using low cost nanoparticulate structures manufactured in a related MDF Project using nanofermentation techniques, 2) evaluate the use of silver based conductive inks developed by project partner NovaCentrix for electronic device fabrication, and 3) demonstrate a suite of low cost printed sensors developed using non-vacuum deposition techniques which involved the integration of metal and semiconductor layers to establish a diverse sensor platform technology.« less

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...

Effect of mesh-peel ply variation on mechanical properties of E-glas composite by infusion vacuum method

NASA Astrophysics Data System (ADS)

Abdurohman, K.; Siahaan, Mabe

2018-04-01

Composite materials made of glass fiber EW-135 with epoxy lycal resin with vacuum infusion method have been performed. The dried glass fiber is arranged in a mold then connected to a vacuum machine and a resin tube. Then, the vacuum machine is turned on and at the same time the resin is sucked and flowed into the mold. This paper reports on the effect of using mesh- peel ply singles on upper-side laminates called A and the effect of using double mesh-peel ply on upper and lower-side laminates call B with glass fiber arrangement is normal and ± 450 in vacuum infusion process. Followed by the manufacture of tensile test specimen and tested its tensile strength with universal test machine 100kN Tensilon RTF 2410, at room temperature with constant crosshead speed. From tensile test results using single and double layers showed that double mesh-peel ply can increase tensile strength 14% and Young modulus 17%.

Thermal vacuum life test facility for radioisotope thermoelectric generators

NASA Astrophysics Data System (ADS)

Deaton, R. L.; Goebel, C. J.; Amos, W. R.

In the late 1970's, the Department of Energy (DOE) assigned Monsanto Research Corporation, Mound Facility, now operated by EG and G Mound Applied Technologies, the responsibility for assembling and testing General Purpose Heat Source (GPHS) radioisotope thermoelectric generators (RTGs). Assembled and tested were five RTGs, which included four flight units and one non-flight qualification unit. Figure 1 shows the RTG, which was designed by General Electric AstroSpace Division (GE/ASD) to produce 285 W of electrical power. A detailed description of the processes for RTG assembly and testing is presented by Amos and Goebel (1989). The RTG performance data are described by Bennett, et al., (1986). The flight units will provide electrical power for the National Aeronautics and Space Administration's (NASA) Galileo mission to Jupiter (two RTGs) and the joint NASA/European Space Agency (ESA) Ulysses mission to study the polar regions of the sun (one RTG). The remaining flight unit will serve as the spare for both missions, and a non-flight qualification unit was assembled and tested to ensure that performance criteria were adequately met.

Development and fabrication of the vacuum systems for an elliptically polarized undulator at Taiwan Photon Source

NASA Astrophysics Data System (ADS)

Chang, Chin-Chun; Chan, Che-Kai; Wu, Ling-Hui; Shueh, Chin; Shen, I.-Ching; Cheng, Chia-Mu; Yang, I.-Chen

2017-05-01

Three sets of a vacuum system were developed and fabricated for elliptically polarized undulators (EPU) of a 3-GeV synchrotron facility. These chambers were shaped with low roughness extrusion and oil-free machining; the design combines aluminium and stainless steel. The use of a bimetallic material to connect the EPU to the vacuum system achieves the vacuum sealing and to resolve the leakage issue due to bake process induced thermal expansion difference. The interior of the EPU chamber consists of a non-evaporable-getter strip pump in a narrow space to absorb photon-stimulated desorption and to provide a RF bridge design to decrease impedance effect in the two ends of EPU chamber. To fabricate these chambers and to evaluate the related performance, we performed a computer simulation to optimize the structure. During the machining and welding, the least deformation was achieved, less than 0.1 mm near 4 m. In the installation, the linear slider can provide a stable and precision moved along parallel the electron beam direction smoothly for the EPU chamber to decrease the twist issue during baking process. The pressure of the EPU chamber attained less than 2×10-8 Pa through baking. These vacuum systems of the EPU magnet have been installed in the electron storage ring of Taiwan Photon Source in 2015 May and have normally operated at 300 mA continuously since, and to keep beam life time achieved over than 12 h.

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...

Plates for vacuum thermal fusion

DOEpatents

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.

Inflation from the Superstring Vacuum

NASA Astrophysics Data System (ADS)

Pollock, M. D.

Quartic higher-derivative gravitational terms in the effective Lagrangian of the heterotic superstring theory renormalize the bare, four-dimensional gravitational coupling κ 02≡ 8π G0, due to the reduction process hat { R}4-> Rbar { R}3, according to the formula κ -2 = κ 0-2 [1+15ζ (3)bar χ/16λ B r3 + bar χ/384π 2 Ar ], where Ar and Br are the moduli for the physical space gij(xk) and internal space bar {g}μ ν (yξ ), respectively. The Euler characteristic bar χ is negative for a three-generation Calabi-Yau manifold, and therefore both the additional terms, of tree-level and one-loop origin, produce a decrease in κ-2, which changes sign when κ-2 = 0. The corresponding tree-level critical point is B rc = [15 ζ (3)|bar χ|/16λ ]1/3 = 0.357, if we set bar χ = -6 and λ = 15π2, for compactification onto a torus. Values B r < B rc yield the anti-gravity region κ-2 < 0, which is analytically accessible from the normal gravity region κ-2 > 0. The only non-singular, vacuum minimum of the potential V(B r) ≡ (15)/(32)ζ (3)bar χλ -1κ 0-2R B r-3-A tilde r {B} { R}2 B r-2 is located at the point B r=[1 + 1.58(2/A r) (4/˜ B) × 10-4] B rc, where κ -2 = 4.73(2/Ar )(4/˜ B) × 10-4κ 0-2, the quadratic trace anomaly { R}2 anom dominates over { R}4, and a phase of de Sitter expansion may occur, as first envisaged by Starobinsky, in approximate agreement with the constraint due to the effect of gravitational waves upon the anisotropy of the cosmic microwave background radiation. There is no non-singular minimum of the potential V(A r) ≡ bar χκ 0-2RA_ r-1/768π 2 - ((1)/(4) { R}2E + ˜ {B} B r-2 { R}2 )Ar.

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...

Relocation of the Cryo-Test Facility to NASA-MSFC

NASA Technical Reports Server (NTRS)

Sisco, Jimmy D.; McConnaughey, Paul K. (Technical Monitor)

2002-01-01

The Environmental Test Facility (ETF), located at NASA-Marshall Space Flight Center, Huntsville, Alabama, has provided thermal vacuum testing for several major programs since the 1960's. The ETF consists of over 13 thermal vacuum chambers sized and configured to handle the majority of test payloads. Testing is performed around the clock with multiple tests being conducted simultaneously. Chamber selection to achieve the best match with test articles and juggling program schedules, at times, can be a challenge. The ETF's Sunspot chamber has had tests scheduled and operated back-to-back for several years and provides the majority of schedule conflicts. Future test programs have been identified which surpass the current Sunspot availability. This paper describes a very low cost alternate to reduce schedule conflicts by utilizing government excess equipment

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. ...

Hazard Analysis for Building 34 Vacuum Glove Box Assembly

NASA Technical Reports Server (NTRS)

Meginnis, Ian

2014-01-01

One of the characteristics of an effective safety program is the recognition and control of hazards before mishaps or failures occur. Conducting potentially hazardous tests necessitates a thorough hazard analysis in order to prevent injury to personnel, and to prevent damage to facilities and equipment. The primary purpose of this hazard analysis is to define and address the potential hazards and controls associated with the Building 34 Vacuum Glove Box Assembly, and to provide the applicable team of personnel with the documented results. It is imperative that each member of the team be familiar with the hazards and controls associated with his/her particular tasks, assignments and activities while interfacing with facility test systems, equipment and hardware. In fulfillment of the stated purposes, the goal of this hazard analysis is to identify all hazards that have the potential to harm personnel, damage the facility or its test systems or equipment, test articles, Government or personal property, or the environment. This analysis may also assess the significance and risk, when applicable, of lost test objectives when substantial monetary value is involved. The hazards, causes, controls, verifications, and risk assessment codes have been documented on the hazard analysis work sheets in Appendix A of this document. The preparation and development of this report is in accordance with JPR 1700.1, "JSC Safety and Health Handbook" and JSC 17773 Rev D "Instructions for Preparation of Hazard Analysis for JSC Ground Operations".

Vacuum coupling of rotating superconducting rotor

DOEpatents

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.

9 CFR 590.548 - Drying, blending, packaging, and heat treatment rooms and facilities.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Drying, blending, packaging, and heat..., blending, packaging, and heat treatment rooms and facilities. (a) General. Processing rooms shall be... vacuum cleaned daily. (c) The heat treatment room shall be of an approved construction and be maintained...

9 CFR 590.548 - Drying, blending, packaging, and heat treatment rooms and facilities.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Drying, blending, packaging, and heat..., blending, packaging, and heat treatment rooms and facilities. (a) General. Processing rooms shall be... vacuum cleaned daily. (c) The heat treatment room shall be of an approved construction and be maintained...

9 CFR 590.548 - Drying, blending, packaging, and heat treatment rooms and facilities.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Drying, blending, packaging, and heat..., blending, packaging, and heat treatment rooms and facilities. (a) General. Processing rooms shall be... vacuum cleaned daily. (c) The heat treatment room shall be of an approved construction and be maintained...

9 CFR 590.548 - Drying, blending, packaging, and heat treatment rooms and facilities.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Drying, blending, packaging, and heat..., blending, packaging, and heat treatment rooms and facilities. (a) General. Processing rooms shall be... vacuum cleaned daily. (c) The heat treatment room shall be of an approved construction and be maintained...

10 CFR 70.64 - Requirements for new facilities or new processes at existing facilities.

Code of Federal Regulations, 2011 CFR

2011-01-01

... behavior of items relied on for safety. (b) Facility and system design and facility layout must be based on... existing facilities. (a) Baseline design criteria. Each prospective applicant or licensee shall address the following baseline design criteria in the design of new facilities. Each existing licensee shall address the...

10 CFR 70.64 - Requirements for new facilities or new processes at existing facilities.

Code of Federal Regulations, 2013 CFR

2013-01-01

... behavior of items relied on for safety. (b) Facility and system design and facility layout must be based on... existing facilities. (a) Baseline design criteria. Each prospective applicant or licensee shall address the following baseline design criteria in the design of new facilities. Each existing licensee shall address the...

10 CFR 70.64 - Requirements for new facilities or new processes at existing facilities.

Code of Federal Regulations, 2012 CFR

2012-01-01

... behavior of items relied on for safety. (b) Facility and system design and facility layout must be based on... existing facilities. (a) Baseline design criteria. Each prospective applicant or licensee shall address the following baseline design criteria in the design of new facilities. Each existing licensee shall address the...

10 CFR 70.64 - Requirements for new facilities or new processes at existing facilities.

Code of Federal Regulations, 2014 CFR

2014-01-01

... behavior of items relied on for safety. (b) Facility and system design and facility layout must be based on... existing facilities. (a) Baseline design criteria. Each prospective applicant or licensee shall address the following baseline design criteria in the design of new facilities. Each existing licensee shall address the...

Pressure-Fed LOX/LCH4 Reaction Control System for Spacecraft: Transient Modeling and Thermal Vacuum Hotfire Test Results

NASA Technical Reports Server (NTRS)

Atwell, Matthew J.; Hurlbert, Eric A.; Melcher, J. C.; Morehead, Robert L.

2017-01-01

An integrated cryogenic liquid oxygen, liquid methane (LOX/LCH4) reaction control system (RCS) was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. The RCS is a subsystem of the Integrated Cryogenic Propulsion Test Article (ICPTA), a pressure-fed LOX/LCH4 propulsion system composed of a single 2,800 lbf main engine, two 28 lbf RCS engines, and two 7 lbf RCS engines. Propellants are stored in four 48 inch diameter 5083 aluminum tanks that feed both the main engine and RCS engines in parallel. Helium stored cryogenically in a composite overwrapped pressure vessel (COPV) flows through a heat exchanger on the main engine before being used to pressurize the propellant tanks to a design operating pressure of 325 psi. The ICPTA is capable of simultaneous main engine and RCS operation. The RCS engines utilize a coil-on-plug (COP) ignition system designed for operation in a vacuum environment, eliminating corona discharge issues associated with a high voltage lead. There are two RCS pods on the ICPTA, with two engines on each pod. One of these two engines is a heritage flight engine from Project Morpheus. Its sea level nozzle was removed and replaced by an 85:1 nozzle machined using Inconel 718, resulting in a maximum thrust of 28 lbf under altitude conditions. The other engine is a scaled down version of the 28 lbf engine, designed to match the core and overall mixture ratios as well as other injector characteristics. This engine can produce a maximum thrust of 7 lbf with an 85:1 nozzle that was additively manufactured using Inconel 718. Both engines are film-cooled and capable of limited duration gas-gas and gas-liquid operation, as well as steady-state liquid-liquid operation. Each pod contains one of each version, such that two engines of the same thrust level can be fired as a couple on opposite pods. The RCS feed system is composed of symmetrical 3/8 inch lines

Small dark energy and stable vacuum from Dilaton-Gauss-Bonnet coupling in TMT

NASA Astrophysics Data System (ADS)

Guendelman, Eduardo I.; Nishino, Hitoshi; Rajpoot, Subhash

2017-04-01

In two measures theories (TMT), in addition to the Riemannian measure of integration, being the square root of the determinant of the metric, we introduce a metric-independent density Φ in four dimensions defined in terms of scalars \\varphi _a by Φ =\\varepsilon ^{μ ν ρ σ } \\varepsilon _{abcd} (partial _{μ }\\varphi _a)(partial _{ν }\\varphi _b) (partial _{ρ }\\varphi _c) (partial _{σ }\\varphi _d). With the help of a dilaton field φ we construct theories that are globally scale invariant. In particular, by introducing couplings of the dilaton φ to the Gauss-Bonnet (GB) topological density {√{-g}} φ ( R_{μ ν ρ σ }^2 - 4 R_{μ ν }^2 + R^2 ) we obtain a theory that is scale invariant up to a total divergence. Integration of the \\varphi _a field equation leads to an integration constant that breaks the global scale symmetry. We discuss the stabilizing effects of the coupling of the dilaton to the GB-topological density on the vacua with a very small cosmological constant and the resolution of the `TMT Vacuum-Manifold Problem' which exists in the zero cosmological-constant vacuum limit. This problem generically arises from an effective potential that is a perfect square, and it gives rise to a vacuum manifold instead of a unique vacuum solution in the presence of many different scalars, like the dilaton, the Higgs, etc. In the non-zero cosmological-constant case this problem disappears. Furthermore, the GB coupling to the dilaton eliminates flat directions in the effective potential, and it totally lifts the vacuum-manifold degeneracy.

Analysis of Fe V and Ni V Wavelength Standards in the Vacuum Ultraviolet

NASA Astrophysics Data System (ADS)

Ward, Jacob Wolfgang; Nave, Gillian

2015-01-01

The recent publication[1] by J.C. Berengut et al. tests for a potential variation in the fine-structure constant in the presence of high gravitational potentials through spectral analysis of white-dwarf stars.The spectrum of the white-dwarf star studied in the paper, G191-B2B, has prominent Fe V and Ni V lines, which were used to determine any variation in the fine-structure constant via observed shifts in the wavelengths of Fe V and Ni V in the vacuum ultraviolet region. The results of the paper indicate no such variation, but suggest that refined laboratory values for the observed wavelengths could greatly reduce the uncertainty associated with the paper's findings.An investigation of Fe V and Ni V spectra in the vacuum ultraviolet region has been conducted to reduce wavelength uncertainties currently limiting modern astrophysical studies of this nature. The analyzed spectra were produced by a sliding spark light source with electrodes made of invar, an iron nickel alloy, at peak currents of 750-2000 A. The use of invar ensures that systematic errors in the calibration are common to both species. The spectra were recorded with the NIST Normal Incidence Vacuum Spectrograph on phosphor image plate and photographic plate detectors. Calibration was done with a Pt II spectrum produced by a Platinum Neon Hollow Cathode lamp.[1] J. C. Berengut, V. V. Flambaum, A. Ong, et al Phys. Rev. Lett. 111, 010801 (2013)

Optomechanical design and construction of a vacuum-compatible optical parametric oscillator for generation of squeezed light

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

Wade, A. R.; Mansell, G. L.; McRae, T. G., E-mail: Terry.Mcrae@anu.edu.au

With the recent detection of gravitational waves, non-classical light sources are likely to become an essential element of future detectors engaged in gravitational wave astronomy and cosmology. Operating a squeezed light source under high vacuum has the advantages of reducing optical losses and phase noise compared to techniques where the squeezed light is introduced from outside the vacuum. This will ultimately provide enhanced sensitivity for modern interferometric gravitational wave detectors that will soon become limited by quantum noise across much of the detection bandwidth. Here we describe the optomechanical design choices and construction techniques of a near monolithic glass opticalmore » parametric oscillator that has been operated under a vacuum of 10{sup −6} mbar. The optical parametric oscillator described here has been shown to produce 8.6 dB of quadrature squeezed light in the audio frequency band down to 10 Hz. This performance has been maintained for periods of around an hour and the system has been under vacuum continuously for several months without a degradation of this performance.« less

Optomechanical design and construction of a vacuum-compatible optical parametric oscillator for generation of squeezed light.

PubMed

Wade, A R; Mansell, G L; McRae, T G; Chua, S S Y; Yap, M J; Ward, R L; Slagmolen, B J J; Shaddock, D A; McClelland, D E

2016-06-01

With the recent detection of gravitational waves, non-classical light sources are likely to become an essential element of future detectors engaged in gravitational wave astronomy and cosmology. Operating a squeezed light source under high vacuum has the advantages of reducing optical losses and phase noise compared to techniques where the squeezed light is introduced from outside the vacuum. This will ultimately provide enhanced sensitivity for modern interferometric gravitational wave detectors that will soon become limited by quantum noise across much of the detection bandwidth. Here we describe the optomechanical design choices and construction techniques of a near monolithic glass optical parametric oscillator that has been operated under a vacuum of 10(-6) mbar. The optical parametric oscillator described here has been shown to produce 8.6 dB of quadrature squeezed light in the audio frequency band down to 10 Hz. This performance has been maintained for periods of around an hour and the system has been under vacuum continuously for several months without a degradation of this performance.

Optomechanical design and construction of a vacuum-compatible optical parametric oscillator for generation of squeezed light

NASA Astrophysics Data System (ADS)

Wade, A. R.; Mansell, G. L.; McRae, T. G.; Chua, S. S. Y.; Yap, M. J.; Ward, R. L.; Slagmolen, B. J. J.; Shaddock, D. A.; McClelland, D. E.

2016-06-01

With the recent detection of gravitational waves, non-classical light sources are likely to become an essential element of future detectors engaged in gravitational wave astronomy and cosmology. Operating a squeezed light source under high vacuum has the advantages of reducing optical losses and phase noise compared to techniques where the squeezed light is introduced from outside the vacuum. This will ultimately provide enhanced sensitivity for modern interferometric gravitational wave detectors that will soon become limited by quantum noise across much of the detection bandwidth. Here we describe the optomechanical design choices and construction techniques of a near monolithic glass optical parametric oscillator that has been operated under a vacuum of 10-6 mbar. The optical parametric oscillator described here has been shown to produce 8.6 dB of quadrature squeezed light in the audio frequency band down to 10 Hz. This performance has been maintained for periods of around an hour and the system has been under vacuum continuously for several months without a degradation of this performance.

Ongoing transmission of hepatitis B virus infection among inmates at a state correctional facility.

PubMed

Khan, Amy J; Simard, Edgar P; Bower, William A; Wurtzel, Heather L; Khristova, Marina; Wagner, Karla D; Arnold, Kathryn E; Nainan, Omana V; LaMarre, Madeleine; Bell, Beth P

2005-10-01

We sought to determine hepatitis B virus (HBV) infection prevalence, associated exposures, and incidence among male inmates at a state correctional facility. A cross-sectional serological survey was conducted in June 2000, and susceptible inmates were retested in June 2001. At baseline, 230 inmates (20.5%; 95% confidence interval [CI]=18.2%, 22.9%) exhibited evidence of HBV infection, including 11 acute and 11 chronic infections. Inmates with HBV infection were more likely than susceptible inmates to have injected drugs (38.8% vs 18.0%; adjusted prevalence odds ratio [OR]=3.0; 95% CI=1.9, 4.9), to have had more than 25 female sex partners (27.7% vs 17.5%; adjusted prevalence OR=2.0; 95% CI=1.4, 3.0), and to have been incarcerated for more than 14 years (38.4% vs 17.6%; adjusted prevalence OR=1.7; 95% CI=1.1, 2.6). One year later, 18 (3.6%) showed evidence of new HBV infection. Among 19 individuals with infections, molecular analysis identified 2 clusters involving 10 inmates, each with a unique HBV sequence. We documented ongoing HBV transmission at a state correctional facility. Similar transmission may occur at other US correctional facilities and could be prevented by vaccination of inmates.

Primordial gravitational waves in running vacuum cosmologies

NASA Astrophysics Data System (ADS)

Tamayo, D. A.; Lima, J. A. S.; Alves, M. E. S.; de Araujo, J. C. N.

2017-01-01

We investigate the cosmological production of gravitational waves in a nonsingular flat cosmology powered by a "running vacuum" energy density described by ρΛ ≡ ρΛ(H), a phenomenological expression potentially linked with the renormalization group approach in quantum field theory in curved spacetimes. The model can be interpreted as a particular case of the class recently discussed by Perico et al. (2013) [25] which is termed complete in the sense that the cosmic evolution occurs between two extreme de Sitter stages (early and late time de Sitter phases). The gravitational wave equation is derived and its time-dependent part numerically integrated since the primordial de Sitter stage. The generated spectrum of gravitons is also compared with the standard calculations where an abrupt transition, from the early de Sitter to the radiation phase, is usually assumed. It is found that the stochastic background of gravitons is very similar to the one predicted by the cosmic concordance model plus inflation except at higher frequencies (ν ≳ 100 kHz). This remarkable signature of a "running vacuum" cosmology combined with the proposed high frequency gravitational wave detectors and measurements of the CMB polarization (B-modes) may provide a new window to confront more conventional models of inflation.

Portable ultrahigh-vacuum sample storage system for polarization-dependent total-reflection fluorescence x-ray absorption fine structure spectroscopy

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

Watanabe, Yoshihide, E-mail: e0827@mosk.tytlabs.co.jp; Nishimura, Yusaku F.; Suzuki, Ryo

A portable ultrahigh-vacuum sample storage system was designed and built to investigate the detailed geometric structures of mass-selected metal clusters on oxide substrates by polarization-dependent total-reflection fluorescence x-ray absorption fine structure spectroscopy (PTRF-XAFS). This ultrahigh-vacuum (UHV) sample storage system provides the handover of samples between two different sample manipulating systems. The sample storage system is adaptable for public transportation, facilitating experiments using air-sensitive samples in synchrotron radiation or other quantum beam facilities. The samples were transferred by the developed portable UHV transfer system via a public transportation at a distance over 400 km. The performance of the transfer system was demonstratedmore » by a successful PTRF-XAFS study of Pt{sub 4} clusters deposited on a TiO{sub 2}(110) surface.« less

Development of a Test Facility for Air Revitalization Technology Evaluation

NASA Technical Reports Server (NTRS)

Lu, Sao-Dung; Lin, Amy; Campbell, Melissa; Smith, Frederick; Curley, Su

2007-01-01

Development of new air revitalization system (ARS) technology can initially be performed in a subscale laboratory environment, but in order to advance the maturity level, the technology must be tested in an end-to-end integrated environment. The Air Revitalization Technology Evaluation Facility (ARTEF) at the NASA Johnson Space Center serves as a ground test bed for evaluating emerging ARS technologies in an environment representative of spacecraft atmospheres. At the center of the ARTEF is a hypobaric chamber which serves as a sealed atmospheric chamber for closed loop testing. A Human Metabolic Simulator (HMS) was custom-built to simulate the consumption of oxygen, and production of carbon dioxide, moisture and heat of up to eight persons. A multitude of gas analyzers and dew point sensors are used to monitor the chamber atmosphere upstream and downstream of a test article. A robust vacuum system is needed to simulate the vacuum of space. A reliable data acquisition and control system is required to connect all the subsystems together. This paper presents the capabilities of the integrated test facility and some of the issues encountered during the integration.

Space Power Facility Readiness for Space Station Power System Testing

NASA Technical Reports Server (NTRS)

Smith, Roger L.

1995-01-01

This document provides information which shows that the NASA Lewis Research Center's Space Power Facility (SPF) will be ready to execute the Space Station electric power system thermal vacuum chamber testing. The SPF is located at LeRC West (formerly the Plum Brook Station), Sandusky, Ohio. The SPF is the largest space environmental chamber in the world, having an inside horizontal diameter of 100 ft. and an inside height at the top of the hemisphere of 122 ft. The vacuum system can achieve a pressure lower than 1 x 10(exp -5) Torr. The cryoshroud, cooled by gaseous nitrogen, can reach a temperature of -250 F, and is 80 ft. long x 40 ft. wide x 22 ft. high. There is access to the chamber through two 50 ft. x 50 ft. doors. Each door opens into an assembly area about 150 ft. long x 70 ft. wide x 80 ft. high. Other available facilities are offices, shop area, data acquisition system with 930 pairs of hard lines, 7 megawatts of power to chamber, 245K gal. liquid nitrogen storage, cooling tower, natural gas, service air, and cranes up to 25 tons.

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.

Vacuum tool manipulator

DOEpatents

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.

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

DOEpatents

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

DOEpatents

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.

Production of primordial gravitational waves in a simple class of running vacuum cosmologies

NASA Astrophysics Data System (ADS)

Tamayo, D. A.; Lima, J. A. S.; Bessada, D. F. A.

The problem of cosmological production of gravitational waves (GWs) is discussed in the framework of an expanding, spatially homogeneous and isotropic FRW type universe with time-evolving vacuum energy density. The GW equation is established and its modified time-dependent part is analytically resolved for different epochs in the case of a flat geometry. Unlike the standard ΛCDM cosmology (no interacting vacuum), we show that GWs are produced in the radiation era even in the context of general relativity. We also show that for all values of the free parameter, the high frequency modes are damped out even faster than in the standard cosmology both in the radiation and matter-vacuum dominated epoch. The formation of the stochastic background of gravitons and the remnant power spectrum generated at different cosmological eras are also explicitly evaluated. It is argued that measurements of the CMB polarization (B-modes) and its comparison with the rigid ΛCDM model plus the inflationary paradigm may become a crucial test for dynamical dark energy models in the near future.

In-Vacuum Photogrammetry of a Ten-Meter Square Solar Sail

NASA Technical Reports Server (NTRS)

Pappa, Richard S.; Jones, Thomas W.; Lunsford, Charles B.; Meyer, Christopher G.

2006-01-01

Solar sailing is a promising, future in-space propulsion method that uses the small force of reflecting sunlight to accelerate a large, reflective membrane without expendable propellants. One of two solar sail configurations under development by NASA is a striped net approach by L'Garde, Inc. This design uses four inflatably deployed, lightweight booms supporting a network of thin strings onto which four quadrants of ultrathin aluminized membranes are attached. The NASA Langley Research Center (LaRC) provided both experimental and analytical support to L'Garde for validating the structural characteristics of this unique, ultralightweight spacecraft concept. One of LaRC's responsibilities was to develop and apply photogrammetric methods to measure sail shape. The deployed shape provides important information for validating the accuracy of finite-element modeling techniques. Photogrammetry is the science and art of calculating 3D coordinates of targets or other distinguishing features on structures using images. A minimum of two camera views of each target is required for 3D determination, but having four or more camera views is preferable for improved reliability and accuracy. Using retroreflective circular targets typically provides the highest measurement accuracy and automation. References 3 and 4 provide details of photogrammetry technology, and reference 5 discusses previous experiences with photogrammetry for measuring gossamer spacecraft structures such as solar sails. This paper discusses the experimental techniques used to measure a L Garde 10-m solar sail test in vacuum with photogrammetry. The test was conducted at the NASA-Glenn Space Power Facility (SPF) located at Plum Brook Station in Sandusky, Ohio. The SPF is the largest vacuum chamber in the United States, measuring 30 m in diameter by 37 m in height. High vacuum levels (10(exp -6) torr) can be maintained inside the chamber, and cold environments (-195 C) are possible using variable

Sugar maple sap volume increases as vacuum level is increased

Treesearch

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...