WorldWideScience

Sample records for ltc vacuum blasting

  1. LTC vacuum blasting machine (concrete): Baseline report

    International Nuclear Information System (INIS)

    1997-01-01

    The LTC shot blast technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU's evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The LTC 1073 Vacuum Blasting Machine uses a high-capacity, direct-pressure blasting system which incorporates a continuous feed for the blast media. The blast media cleans the surface within the contained brush area of the blast. It incorporates a vacuum system which removes dust and debris from the surface as it is blasted. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure during maintenance activities was minimal, but due to mechanical difficulties dust monitoring could not be conducted during operation. Noise exposure was significant. Further testing for each of these exposures is recommended because of the outdoor environment where the testing demonstration took place. This may cause the results to be inaccurate. It is feasible that the dust and noise levels will be higher in an enclosed environment. In addition, other safety and health issues found were ergonomics, heat stress, tripping hazards, electrical hazards, lockout/tagout, and arm-hand vibration

  2. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    International Nuclear Information System (INIS)

    McPhee, William S.

    1999-01-01

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

  3. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    International Nuclear Information System (INIS)

    McPhee, William S.

    2001-01-01

    The Department of Energy (DOE) needs improved technologies to decontaminate large areas of both concrete and steel surfaces. The technology should have high operational efficiency, minimize exposures to workers, and produce low levels of secondary waste. In order to meet the DOE's needs, an applied research and development project for the improvement of a current decontamination technology, Vacuum Blasting, is proposed. The objective of this project is to improve the productivity and lower the expense of the existing vacuum blasting technology which has been widely used in DOE sites for removing radioactive contamination, PCBs, and lead-based paint. The proposed work would increase the productivity rate and provide safe and cost-effective decontamination of the DOE sites

  4. PTC-6 vacuum system: WallWaler trademark Blastrac reg-sign shot blast cleaning system

    International Nuclear Information System (INIS)

    1998-02-01

    The LTC Americas, Inc. wall decontamination technology consisted of two pneumatic hand-held tools: (1) a roto-peen scaler that used star cutters and (2) a 3-piston hammer with reciprocating bits. The hand-held tools were used in conjunction with the LTC PTC-6 vacuum system which captured dust and debris as the wall decontamination took place. Recommendations for improved worker safety and health during use of the PTC-6 vacuum system with hand-held tools include: (1) keeping all hoses and lines as orderly as possible in compliance with good housekeeping requirements; (2) ergonomic training to include techniques in lifting, bending, stooping, twisting, etc.; (3) use of a clamping system to hold hoses to the vacuum system; (4) a safety line on the air line connections; (5) use of a mechanical lifting system for waste drum removal; and (6) the use of ergonomically designed tools

  5. Philips LTC 2009/51

    CERN Multimedia

    1999-01-01

    It was part of a range of high-performance monitors (computers screens) that were associated with other units such as Philip's video surveillance systems, cameras or transmission and control equipment. Included in this range of Philips monitors are LTC 2009 (like this one), LTC 2012, LTC 2017 and LTC 2020 Series monochrome monitors. They offer high-performance images with a resolution of 900 TVL (TV-Lines), or in the case of the LTC 2017 monitor, 700 TVL, making them ideal for remote viewing and video applications. The monitor housing consists of a robust rectangular metal case which minimizes interference from external signals and allows “stacking” of monitors when used in large numbers.

  6. PTC-6 vacuum system: WallWalker{trademark} and Blastrac{reg_sign} shot blast cleaning system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    The LTC Americas, Inc. wall decontamination technology consisted of two pneumatic hand-held tools: (1) a roto-peen scaler that used star cutters and (2) a 3-piston hammer with reciprocating bits. The hand-held tools were used in conjunction with the LTC PTC-6 vacuum system which captured dust and debris as the wall decontamination took place. Recommendations for improved worker safety and health during use of the PTC-6 vacuum system with hand-held tools include: (1) keeping all hoses and lines as orderly as possible in compliance with good housekeeping requirements; (2) ergonomic training to include techniques in lifting, bending, stooping, twisting, etc.; (3) use of a clamping system to hold hoses to the vacuum system; (4) a safety line on the air line connections; (5) use of a mechanical lifting system for waste drum removal; and (6) the use of ergonomically designed tools.

  7. 42 CFR 412.515 - LTC-DRG weighting factors.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false LTC-DRG weighting factors. 412.515 Section 412.515 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICARE...-Term Care Hospitals § 412.515 LTC-DRG weighting factors. For each LTC-DRG, CMS assigns an appropriate...

  8. 42 CFR 412.517 - Revision of LTC-DRG group classifications and weighting factors.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Revision of LTC-DRG group classifications and... the LTC-DRG classifications and recalibration of the weighting factors described in paragraph (a) of... SERVICES Prospective Payment System for Long-Term Care Hospitals § 412.517 Revision of LTC-DRG group...

  9. FINAL Report LTC-DOE DE-EE0000537

    Energy Technology Data Exchange (ETDEWEB)

    Gibbs, Michelle [Lakeshore Technical College, Cleveland, WI (United States)

    2013-02-28

    At the time of LTC’s application we were home to a small / mid-sized Wind Energy Research and Teaching Center, funded in part by We Energies, and offered the state of Wisconsin’s first Associate of Applied Science (A.A.S.) Degree in Wind Energy Technology. With President Obama promising investment in wind, LTC and its partners were uniquely situated to meet the challenge through an organized career pathways approach that utilized industry drivers and occupationally verified curriculum to train the workers who “transform our energy sector.” LTC’s employer partners validated the findings of the “20% Wind Energy by 2030: Increasing Wind Energy's Contribution to U.S. Electricity Supply” report by the US Department of Energy which recognized programs like LTC’s as an “excellent beginning,” noting that many more like them are necessary to meet the challenges of the 20% Wind scenario.One of the focuses of the study was the lack of trained technicians to work on installation and maintenance of renewables (and more specifically for our grant application wind turbines). LTC’s goal, made possible with the funding provided in this grant, was to increase the number of skilled graduates to help meet this national objective. LTC was already a leader in wind for the state of Wisconsin but wanted to upscale from a single school to a statewide (and potentially regional) center for wind energy. LTC planned to leverage our facilities, curriculum, and faculty expertise to meet this goal.

  10. Binding sites for 3H-LTC4 in membranes from guinea pig ileal longitudinal muscle

    International Nuclear Information System (INIS)

    Nicosia, S.; Crowley, H.J.; Oliva, D.; Welton, A.F.

    1984-01-01

    Leutriene (LTC4) is one of the components of Slow Reacting Substance of Anaphylaxis (SRS-A) and is a potent constrictor of guinea pig ilea. The contraction is likely to be a receptor-mediated process. Here the authors report the existence of specific binding sites for 3 H-LTC4 in a crude membrane preparation from guinea pig ileal longitudinal muscle. At 4 degrees C in the presence of 20 mM Serine-borate, binding increases linearly with protein concentration, reaches equilibrium in 10 minutes, and is reversible upon addition of 3 x 10(-5) M unlabelled LTC4. The dissociation curve is consistent with the existence of more than one class of binding site. Ca++ and Mg++ greatly enhance the binding of 3 H-LTC4 at equilibrium. In the presence of 5 mM CaCl 2 and MgCl 2 not only LTC4 (IC50 10(-7)M), but also LTD4 and the SRS-A antagonist FPL 55712 can compete with 3 H-LTC4 for its binding sites. FPL 55712 only displaces 60-70% of the total amount bound, while LTC4 displaces 90-95%. These studies indicate that multiple classes of binding sites exist for 3 H-LTC4 in guinea pig ileal longitudinal muscle, and that at least part of these binding sites might be related to the ability of LTC4 to contract guinea pig ilea

  11. Latent trait cortisol (LTC) during pregnancy: Composition, continuity, change, and concomitants.

    Science.gov (United States)

    Giesbrecht, Gerald F; Bryce, Crystal I; Letourneau, Nicole; Granger, Douglas A

    2015-12-01

    Individual differences in the activity of the hypothalamic pituitary adrenal (HPA) axis are often operationalized using summary measures of cortisol that are taken to represent stable individual differences. Here we extend our understanding of a novel latent variable approach to latent trait cortisol (LTC) as a measure of trait-like HPA axis function during pregnancy. Pregnant women (n=380) prospectively collected 8 diurnal saliva samples (4 samples/day, 2 days) within each trimester. Saliva was assayed for cortisol. Confirmatory factor analyses were used to fit LTC models to early morning and daytime cortisol. For individual trimester data, only the daytime LTC models had adequate fit. These daytime LTC models were strongly correlated between trimesters and stable over pregnancy. Daytime LTC was unrelated to the cortisol awakening response and the daytime slope but strongly correlated with the area under the curve from ground. The findings support the validity of LTC as a measure of cortisol during pregnancy and suggest that it is not affected by pregnancy-related changes in HPA axis function. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Saiboku-to, a Kampo herbal medicine, inhibits LTC4 release from eosinophils

    Directory of Open Access Journals (Sweden)

    Koichi Hirai

    1998-01-01

    Full Text Available Saiboku-to (TJ-96, a traditional Kampo herbal formation, has been used in the treatment of bronchial asthma in Japan as an anti-allergy herbal medicine. We investigated the effect of TJ-96 on leukotriene (LTC4 release from eosinophils and basophils isolated from healthy volunteers. Pre-incubation of eosinophils with TJ-96 inhibited ionophore- or formyl-methionyl-leucyl-phenylalanine (FMLP-induced LTC4 generation by eosinophils in a dose-dependent fashion. The TJ-96 was more potent in the release by ionophore (IC50 = 60 mg/mL than the release induced by FMLP (IC50 = 300 mg/mL. Maximal inhibition was observed when eosinophils were pretreated with TJ-96 for 5 min. Although TJ-96 at high concentrations inhibited IgE-mediated histamine release from human basophils, inhibition of IgE-mediated LTC4 release was not statistically significant. The potent inhibitory activity was found in the extract of Glycyrrhiza root, one of the herbal components of TJ-96, but the inhibitory effects were not due to either glycyrrhizin or liquiritin, the main elements of the Glycyrrhiza root. These results raise the possibility that the clinical efficacy of TJ-96 is derived, at least in part, from its potent inhibitory effect on LTC4 release from eosinophils.

  13. In vitro assays for cobblestone area-forming cells, LTC-IC, and CFU-C

    NARCIS (Netherlands)

    van Os, Ronald P; Dethmers-Ausema, Bertien; de Haan, Gerald; Bunting, Kevin

    2008-01-01

    Various assays exist that measure the function of hematopoietic stemcells (HSCs). In this chapter, in vitro assays are described that measure the frequency of progenitors (colony-forming unit in culture; CFU-C), stem cells (long-term culture-initiating cell; LTC-IC), or both (cobblestone

  14. Inhibition effects of perfluoroalkyl acids on progesterone production in mLTC-1.

    Science.gov (United States)

    Zhao, Wei; Cui, Ruina; Wang, Jianshe; Dai, Jiayin

    2017-06-01

    Perfluoroalkyl substances (PFASs) are a class of fluorine substituted carboxylic acid, sulfonic acid and alcohol, structurally similar to their corresponding parent compounds. Previous study demonstrated the potential endocrine disruption and reproductive toxicity of perfluorooctane sulfonic acid and perfluorooctanoic acid, two dominant PFASs in animals and humans. We explored the relationship between eleven perfluoroalkyl acids (PFAAs) with different carbon chain length and their ability to inhibit progesterone production in mouse Leydig tumor cells (mLTC-1). We found an obvious dose-response relationship between progesterone inhibition rate and PFAA exposure concentration in mLTC-1. The relative inhibition rate of progesterone by PFAAs was linearly related to the carbon chain length and molar refractivity of PFAAs. Mitochondrial membrane potential (MMP) decreased after PFAA exposure at the half-maximal inhibitory effect concentration (IC 50 ) of progesterone production in mLTC-1, while the reactive oxygen species (ROS) content increased significantly. These results imply that the inhibition effect of PFAAs on progesterone production might be due, in part, to ROS damage and the decrease in MMP in mLTC-1. Copyright © 2016. Published by Elsevier B.V.

  15. Analysis of ATLAS LTC-04R Test for Loop Seal Reformation Phenomena using RELAP5

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang-Gyu; Kim, Dae-Hun; Kim, Han-Gon [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    The loop seal reformation issue was selected to be the analysis topic of the DSP-04 based on the technical discussion between the participants and the operating agencies (KAERI and KINS) and domestic experts meetings. After that, KAERI performed LTC-04R test which is 4 inch top-slot cold-leg break test using ATLAS facility in December 27, 2015. KHNP CRI, as a participant of the DSP-04, performed the blind calculation and open calculation using RELAP5/Mod3.3 patch 3. This paper deals with the results of open calculation for ATLAS LTC-04R test. The results of several sensitivity analyses such as the critical flow modeling sensitivity and break flow system modeling sensitivity will be discussed. Several possible factors in the loop seal reformation behavior are examined in the sensitivity analysis. Heat loss modeling, fine break system modeling, fine loop seal nodalization and off-take modeling are not significant factor in the loop seal reformation. Still critical flow model and discharge coefficient are dominant factors. Based on the ATLAS LTC-04R, Ransom-Trapp model shows better prediction in the break flow than the Henry-Fauske model.

  16. Blast management

    OpenAIRE

    Shouraki, Mohammad Kargar; Naserkheil, Ali Asghar

    2011-01-01

    Blast Management (BM) is composed of the combination of human resources management (HRM) principles and concepts and various methods of quality management (QM) with a financial approach. BM is made up of three aspects: hard, soft and concept and BLAST means an explosive shift in organization's mindset and thought and rapid action against it. The first aspect, hard, includes a set of managerial toots and philosophies to improve the quality and productivity with a financial approach.

  17. A European classification of services for long-term care—the EU-project eDESDE-LTC

    Science.gov (United States)

    Weber, Germain; Brehmer, Barbara; Zeilinger, Elisabeth; Salvador-Carulla, Luis

    2009-01-01

    Purpose and theory The eDESDE-LTC project aims at developing an operational system for coding, mapping and comparing services for long-term care (LTC) across EU. The projects strategy is to improve EU listing and access to relevant sources of healthcare information via development of SEMANTIC INTER-OPERABILITY in eHEALTH (coding and listing of services for LTC); to increase access to relevant sources of information on LTC services, and to improve linkages between national and regional websites; to foster cooperation with international organizations (OECD). Methods This operational system will include a standard classification of main types of care for persons with LTC needs and an instrument for mapping and standard description of services. These instruments are based on previous classification systems for mental health services (ESMS), disabilities services (DESDE) and ageing services (DESDAE). A Delphi panel made by seven partners developed a DESDE-LTC beta version, which was translated into six languages. The feasibility of DESDE-LTC is tested in six countries using national focal groups. Then the final version will be developed by the Delphi panel, a webpage, training material and course will be carried out. Results and conclusions The eDESDE-LTC system will be piloted in two EU countries (Spain and Bulgaria). Evaluation will focus primarily on usability and impact analysis. Discussion The added value of this project is related to the right of “having access to high-quality healthcare when and where it is needed” by EU citizens. Due to semantic variability and service complexity, existing national listings of services do not provide an adequate framework for patient mobility.

  18. CysLT2 receptor activation is involved in LTC4-induced lung air-trapping in guinea pigs.

    Science.gov (United States)

    Sekioka, Tomohiko; Kadode, Michiaki; Yonetomi, Yasuo; Kamiya, Akihiro; Fujita, Manabu; Nabe, Takeshi; Kawabata, Kazuhito

    2017-01-05

    CysLT 1 receptors are known to be involved in the pathogenesis of asthma. However, the functional roles of CysLT 2 receptors in this condition have not been determined. The purpose of this study is to develop an experimental model of CysLT 2 receptor-mediated LTC 4 -induced lung air-trapping in guinea pigs and use this model to clarify the mechanism underlying response to such trapping. Because LTC 4 is rapidly converted to LTD 4 by γ-glutamyltranspeptidase (γ-GTP) under physiological conditions, S-hexyl GSH was used as a γ-GTP inhibitor. In anesthetized artificially ventilated guinea pigs with no S-hexyl GSH treatment, i.v. LTC 4 -induced bronchoconstriction was almost completely inhibited by montelukast, a CysLT 1 receptor antagonist, but not by BayCysLT 2 RA, a CysLT 2 receptor antagonist. The inhibitory effect of montelukast was diminished by treatment with S-hexyl GSH, whereas the effect of BayCysLT 2 RA was enhanced with increasing dose of S-hexyl GSH. Macroscopic and histological examination of lung tissue isolated from LTC 4 -/S-hexyl-GSH-treated guinea pigs revealed air-trapping expansion, particularly at the alveolar site. Inhaled LTC 4 in conscious guinea pigs treated with S-hexyl GSH increased both airway resistance and airway hyperinflation. On the other hand, LTC 4 -induced air-trapping was only partially suppressed by treatment with the bronchodilator salmeterol. Although montelukast inhibition of LTC 4 -induced air-trapping was weak, treatment with BayCysLT 2 RA resulted in complete suppression of this air-trapping. Furthermore, BayCysLT 2 RA completely suppressed LTC 4 -induced airway vascular hyperpermeability. In conclusion, we found in this study that CysLT 2 receptors mediate LTC 4 -induced bronchoconstriction and air-trapping in S-hexyl GSH-treated guinea pigs. It is therefore believed that CysLT 2 receptors contribute to asthmatic response involving air-trapping. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Brain injuries from blast.

    Science.gov (United States)

    Bass, Cameron R; Panzer, Matthew B; Rafaels, Karen A; Wood, Garrett; Shridharani, Jay; Capehart, Bruce

    2012-01-01

    Traumatic brain injury (TBI) from blast produces a number of conundrums. This review focuses on five fundamental questions including: (1) What are the physical correlates for blast TBI in humans? (2) Why is there limited evidence of traditional pulmonary injury from blast in current military field epidemiology? (3) What are the primary blast brain injury mechanisms in humans? (4) If TBI can present with clinical symptoms similar to those of Post-Traumatic Stress Disorder (PTSD), how do we clinically differentiate blast TBI from PTSD and other psychiatric conditions? (5) How do we scale experimental animal models to human response? The preponderance of the evidence from a combination of clinical practice and experimental models suggests that blast TBI from direct blast exposure occurs on the modern battlefield. Progress has been made in establishing injury risk functions in terms of blast overpressure time histories, and there is strong experimental evidence in animal models that mild brain injuries occur at blast intensities that are similar to the pulmonary injury threshold. Enhanced thoracic protection from ballistic protective body armor likely plays a role in the occurrence of blast TBI by preventing lung injuries at blast intensities that could cause TBI. Principal areas of uncertainty include the need for a more comprehensive injury assessment for mild blast injuries in humans, an improved understanding of blast TBI pathophysiology of blast TBI in animal models and humans, the relationship between clinical manifestations of PTSD and mild TBI from blunt or blast trauma including possible synergistic effects, and scaling between animals models and human exposure to blasts in wartime and terrorist attacks. Experimental methodologies, including location of the animal model relative to the shock or blast source, should be carefully designed to provide a realistic blast experiment with conditions comparable to blasts on humans. If traditional blast scaling is

  20. Advanced closed loop combustion control of a LTC diesel engine based on in-cylinder pressure signals

    International Nuclear Information System (INIS)

    Carlucci, A.P.; Laforgia, D.; Motz, S.; Saracino, R.; Wenzel, S.P.

    2014-01-01

    Highlights: • We have proposed an in-cylinder pressure-based closed loop combustion control. • We have tested the control on an engine at the test bench. • We have tested the control on the engine equipping a Euro 6-compliant vehicle. • The control is effective in increasing torque stability and reduce engine noise. - Abstract: The adoption of diesel LTC combustion concepts is widely recognised as a practical way to reduce simultaneously nitric oxides and particulate emission levels from diesel internal combustion engines. However, several challenges have to be faced up when implementing diesel LTC concepts in real application vehicles. In particular, achieving acceptable performance concerning the drivability comfort, in terms of output torque stability and combustion noise during engine dynamic transients, is generally a critical point. One of the most promising solutions to improve the LTC combustion operation lays in the exploitation of closed loop combustion control, based on in-cylinder pressure signals. In this work, the application of an in-cylinder pressure-based closed loop combustion control to a Euro 6-compliant demonstrator vehicle has been developed. The main challenges deriving from the control of the LTC combustion, directly affecting the engine/vehicle performance, have been analysed in detail. In order to overcome these drawbacks, a new control function, integrated into the base closed loop system, has been designed. The performance of the new function have been experimentally tested at the engine test bench. Results showed a significant enhancement of the LTC operation, in terms of both combustion stability and noise reduction during engine transients. The new function was also implemented on a real vehicle, thus proving the potential of the new control concept in realistic operating conditions

  1. Vacuum Technology

    Energy Technology Data Exchange (ETDEWEB)

    Biltoft, P J

    2004-10-15

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

  2. Remote operated vehicle with carbon dioxide blasting (ROVCO2)

    International Nuclear Information System (INIS)

    Resnick, A.M.

    1995-01-01

    The Remote Operated Vehicle with Carbon Dioxide Blasting (ROVCO 2 ), as shown in a front view, is a six-wheeled remote land vehicle used to decontaminate concrete floors. The remote vehicle has a high pressure Cryogenesis blasting subsystem, Oceaneering Technologies (OTECH) developed a CO 2 xY Orthogonal Translational End Effector (COYOTEE) subsystem, and a vacuum/filtration and containment subsystem. Figure 2 shows a block diagram with the various subsystems labeled

  3. Remote operated vehicle with carbon dioxide blasting (ROVCO{sub 2})

    Energy Technology Data Exchange (ETDEWEB)

    Resnick, A.M. [Oceaneering International, Inc., Upper Marlboro, MD (United States)

    1995-10-01

    The Remote Operated Vehicle with Carbon Dioxide Blasting (ROVCO{sub 2}), as shown in a front view is a six-wheeled remote land vehicle used to decontaminate concrete floors. The remote vehicle has a high pressure Cryogenesis blasting subsystem, Oceaneering Technologies (OTECH) developed a CO{sub 2} xY Orthogonal Translational End Effector (COYOTEE) subsystem, and a vacuum/filtration and containment subsystem. The cryogenesis subsystem performs the actual decontamination work and consists of the dry ice supply unit, the blasting nozzle, the remotely controlled electric and pneumatic valves, and the vacuum work-head. The COYOTEE subsystem positions the blasting work-head within a planar work space and the vacuum subsystem provides filtration and containment of the debris generated by the CO{sub 2} blasting. It employs a High Efficiency Particulate Air (HEPA) filtration unit to separate contaminants for disposal. All of the above systems are attached to the vehicle subsystem via the support structure.

  4. Vacuum extraction

    DEFF Research Database (Denmark)

    Maagaard, Mathilde; Oestergaard, Jeanett; Johansen, Marianne

    2012-01-01

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

  5. Vacuum mechatronics

    Science.gov (United States)

    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.

  6. Calculation of driling and blasting parameters in blasting performance

    OpenAIRE

    Dambov, Risto; Karanakova Stefanovska, Radmila; Dambov, Ilija

    2015-01-01

    In all mining technology drilling and blasting parameters and works are one of the main production processes at each mine. The parameters of drilling and blasting and explosives consumption per ton of blasting mass are define economic indicators of any blasting no matter for what purpose and where mining is performed. The calculation of rock blasting should always have in mind that the methodology of calculation of all drilling and blasting parameters in blasting performance are performed for...

  7. Cosmic vacuum

    International Nuclear Information System (INIS)

    Chernin, Artur D

    2001-01-01

    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. (reviews of topical problems)

  8. Cosmic vacuum

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-11-30

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

  9. Vacuum gauges

    International Nuclear Information System (INIS)

    Power, B.D.; Priestland, C.R.D.

    1978-01-01

    This invention relates to vacuum gauges, particularly of the type known as Penning gauges, which are cold cathode ionisation gauges, in which a magnetic field is used to lengthen the electron path and thereby increase the number of ions produced. (author)

  10. LTC: a novel algorithm to improve the efficiency of contig assembly for physical mapping in complex genomes

    Directory of Open Access Journals (Sweden)

    Feuillet Catherine

    2010-11-01

    Full Text Available Abstract Background Physical maps are the substrate of genome sequencing and map-based cloning and their construction relies on the accurate assembly of BAC clones into large contigs that are then anchored to genetic maps with molecular markers. High Information Content Fingerprinting has become the method of choice for large and repetitive genomes such as those of maize, barley, and wheat. However, the high level of repeated DNA present in these genomes requires the application of very stringent criteria to ensure a reliable assembly with the FingerPrinted Contig (FPC software, which often results in short contig lengths (of 3-5 clones before merging as well as an unreliable assembly in some difficult regions. Difficulties can originate from a non-linear topological structure of clone overlaps, low power of clone ordering algorithms, and the absence of tools to identify sources of gaps in Minimal Tiling Paths (MTPs. Results To address these problems, we propose a novel approach that: (i reduces the rate of false connections and Q-clones by using a new cutoff calculation method; (ii obtains reliable clusters robust to the exclusion of single clone or clone overlap; (iii explores the topological contig structure by considering contigs as networks of clones connected by significant overlaps; (iv performs iterative clone clustering combined with ordering and order verification using re-sampling methods; and (v uses global optimization methods for clone ordering and Band Map construction. The elements of this new analytical framework called Linear Topological Contig (LTC were applied on datasets used previously for the construction of the physical map of wheat chromosome 3B with FPC. The performance of LTC vs. FPC was compared also on the simulated BAC libraries based on the known genome sequences for chromosome 1 of rice and chromosome 1 of maize. Conclusions The results show that compared to other methods, LTC enables the construction of highly

  11. A fast reactor transient analysis methodology for PCs: Volume 3, LTC program manual of the QuickBASIC code

    International Nuclear Information System (INIS)

    Ott, K.O.; Chung, L.

    1992-06-01

    This manual augments the detailed manual of the GW-BASIC version of the LTC code for an application in QuickBASIC. As most of the GW-BASIC coding of this program for ''LMR Transient Calculations'' is compatible with QuickBASIC, this manual pertains primarily to the required changes, such as the handling of input and output. The considerable reduction in computation time achieved by this conversion is demonstrated for two sample problems, using a variety of hardware and execution options. The revised code is listed. Although the severe storage limitations of GW-BASIC no longer apply, the LOF transient path has not been completed in this QuickBASIC code. Its advantages are thus primarily in the much faster running time for TOP and LOHS transients. For the fastest PC hardware (486) and execution option the computation time is reduced by a factor of 124 compared to GW-BASIC on a 386/20

  12. Visualization research on spray atomization, evaporation and combustion processes of ethanol–diesel blend under LTC conditions

    International Nuclear Information System (INIS)

    Huang, Sheng; Deng, Peng; Huang, Ronghua; Wang, Zhaowen; Ma, Yinjie; Dai, Hui

    2015-01-01

    Highlights: • Spray combustion of E20 diesel in LTC condition shows a U-shape flame structure. • The chasing behavior of fuel spray exists near the spray axis. • Fuel ignition doesn’t initiate at the spray tip but in peripheral regions behind it. • An improper chamber structure may lead to a long post-combustion duration. - Abstract: Utilization of ethanol in diesel engines has been widely studied by means of engine experiments and emission detection. However, pertinent studies on the spray combustion process of ethanol–diesel blends are scarce. In order to verify the effect of ethanol in modern diesel engines, an experiment is conducted to visualize the spray combustion process of ethanol–diesel blend under LTC conditions. Stages including atomization, evaporation and combustion, are investigated individually to realize synergistic analysis. Meanwhile, considering the long time scale of combustion after fuel injection finishes, characteristics during and after injection period are both targeted in this paper. Moreover, measurement of macroscopic characteristics, such as spray tip penetration, spray spreading cone angle and flame lift off length, provides a quantitative profile of the spray structure. Results show that, evaporation, different from atomization, has little influence on spray penetration, but promotes the spray spreading angle and spray projected area. So does combustion, which enlarges the spray projected area further. Ignition takes place on the periphery behind the spray tip, then quickly extends to the whole head of the spray and forms a U-shape diffusion structure. After the injection period, the residual spray tail develops into wavelike structures due to absence of subsequent entrainment force. Also, the penetration speed falls greatly to an extent much slower than flame propagation, which frees the flame from the lift-off effect. Subsequently, the flame propagates upstream towards the nozzle orifice. After consumed all fuel in

  13. 真空碳热还原酸浸含钛高炉渣制备 TiC 分析%Preparation of TiC by carbothermal reduction in vacuum and acid leaching process using titanium bearing blast furnace slag

    Institute of Scientific and Technical Information of China (English)

    胡蒙均; 尹方庆; 魏瑞瑞; 邓青宇; 扈玫珑

    2015-01-01

    含钛高炉渣中含有20%~30%的 TiO2,是一种附加值较高的二次资源,但在综合利用过程中存在氧化物还原难度大,硅钛难分离,二次污染严重等问题。基于热力学理论基础,采用真空碳热还原联合酸浸工艺处理含钛高炉渣制备 TiC。结果表明:真空有助于钛氧化物彻底还原,可实现渣中硅钛彻底分离,减少酸耗量,降低二次污染。真空碳热还原联合酸浸工艺处理含钛高炉渣(TiO2含量23%左右)制备 TiC 的最佳条件为:炉渣粒度200目,还原温度1673 K,渣碳质量比100∶38。%Titanium bearing blast furnace slag with 20%-30% titanium dioxide is a valuable second resource.The main problems to utilize the resource are the reduction of the titanium oxides,the separation of titanium and silicon and the second pollution.The main aim of the research is to prepare TiC by the united process of carbothermal reduction in vacuum and acid leaching based on the thermodynamics calculation.The results show that decreasing pressure of the system is helpful for the reduction of the titanium oxides.Titanium and silicon in slag can be separated completely.The second pollution decreases due to evaporation of Mg and SiO produced in vacuum condition.The optimum conditions for the united process to prepare TiC are slag size of 200 mesh,temperature of 1 673 K,and the mass ratio of slag to reductant of 100∶38.

  14. Synthesis of leukotrienes labelled with deuterium: [11,12,14,15-2H4]-LTA4, -LTC4, -LTD4 and -LTE4

    International Nuclear Information System (INIS)

    Lellouche, J.P.; Aubert, F.; Noel, J.P.; Boullais, C.; Beaucourt, J.P.

    1989-01-01

    Semi-hydrogenation by D 2 gas on Lindlar catalyst of an acetylenic precursor led to [11,12,14,15- 2 H 4 ]-LTA 4 methyl ester. Nucleophilic opening of the epoxide ring by amino thioacids accorded, after saponification, the corresponding deuterated peptidoleukotrienes LTC 4 , LTD 4 and LTE 4 . (author)

  15. Leybold vacuum handbook

    CERN Document Server

    Diels, K; Diels, Kurt

    1966-01-01

    Leybold Vacuum Handbook presents a collection of data sets that are essential for numerical calculation of vacuum plants and vacuum processes. The title first covers vacuum physics, which includes gas kinetics, flow phenomena, vacuum gauges, and vapor removal. Next, the selection presents data on vacuum, high vacuum process technology, and gas desorption and gettering. The text also deals with materials, vapor pressure, boiling and melting points, and gas permeability. The book will be of great interest to engineers and technicians that deals with vacuum related technologies.

  16. MEA vacuum system

    International Nuclear Information System (INIS)

    Stroo, R.; Schwebke, H.; Heine, E.

    1984-01-01

    This report describes construction and operation of the MEA vacuum system of NIKHEF (Netherlands). First, the klystron vacuum system, beam transport system, diode pump and a triode pump are described. Next, the isolation valve and the fast valves of the vacuum system are considered. Measuring instruments, vacuum system commands and messages of failures are treated in the last chapter. (G.J.P.)

  17. Vacuum system for ISABELLE

    International Nuclear Information System (INIS)

    Hobson, J.P.

    1975-01-01

    An analysis is presented of the proposed vacuum system for the planned ISABELLE storage rings with respect to acceptability and practicality from the vacuum viewport. A comparison is made between the proposed vacuum system and the vacuum system at the CERN ISR, and some comments on various design and operational parameters are made

  18. What are the beliefs, attitudes and practices of front-line staff in long-term care (LTC facilities related to osteoporosis awareness, management and fracture prevention?

    Directory of Open Access Journals (Sweden)

    Adachi Jonathan D

    2010-10-01

    Full Text Available Abstract Background Compared to the general elderly population, those institutionalized in LTC facilities have the highest prevalence of osteoporosis and subsequently have higher incidences of vertebral and hip fractures. The goal of this study is to determine how well nurses at LTC facilities are educated to properly administer bisphosphonates. A secondary question assessed was the nurse's and PSW's attitudes and beliefs regarding the role and benefits of vitamin D for LTC patients. Methods Eight LTC facilities in Hamilton were surveyed, and all nurses were offered a survey. A total 57 registered nurses were surveyed. A 21 item questionnaire was developed to assess existing management practices and specific osteoporosis knowledge areas. Results The questionnaire assessed the nurse's and personal support worker's (PSWs education on how to properly administer bisphosphonates by having them select all applicable responses from a list of options. These options included administering the drug before, after or with meals, given with or separate from other medications, given with juice, given with or without water, given with the patient sitting up, or finally given with the patient supine. Only 52% of the nurses and 8.7% of PSWs administered the drug properly, where they selected the options: (given before meals, given with water, given separate from all other medications, and given in a sitting up position. If at least one incorrect option was selected, then it was scored as an inappropriate administration. Bisphosphonates were given before meals by 85% of nurses, given with water by 90%, given separately from other medication by 71%, and was administered in an upright position by 79%. Only 52% of the nurses and 8.7% of PSWs surveyed were administering the drug properly. Regarding the secondary question, of the 57 nurses surveyed, 68% strongly felt their patients should be prescribed vitamin D supplements. Of the 124 PSWs who completed the survey

  19. The BLAST experiment

    NARCIS (Netherlands)

    Hasell, D.; Botto, T.; van den Brand, J.F.J.

    2009-01-01

    The Bates large acceptance spectrometer toroid (BLAST) experiment was operated at the MIT-Bates Linear Accelerator Center from 2003 until 2005. The detector and experimental program were designed to study, in a systematic manner, the spin-dependent electromagnetic interaction in few-nucleon systems.

  20. Vacuum-assisted delivery

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000514.htm Vacuum-assisted delivery To use the sharing features on this page, ... through the birth canal. When is Vacuum-assisted Delivery Needed? Even after your cervix is fully dilated ( ...

  1. Blasting agents and initiation systems

    Energy Technology Data Exchange (ETDEWEB)

    Fiscor, S.

    2000-01-01

    Although blasting differs between and within each industry, as a whole, the mines and quarries are making a shift from a purely ammonium nitrate/fuel oil (ANFO) mixture to a blend of emulsion and ANFO on a straight emulsion. Non-electric (shock tube) initiation systems have provided a viable alternative to the electric detonator (blasting cap). Explosives manufacturers are seeing their roles changes to being blasting contractors or consultants rather than just suppliers. The article discusses these trends and gives examples of typical blasting techniques and amounts of blasting agent used at large USA surface coal mines. Electric caps are still used in blasting underground coal. The Ensign Bickford Co. (EBCo) is developing electronic detonators and has been field testing an electronic initiator, the DIGIDET detonator, for the last four years. When commercially available, electronic detonators will be accurate but will come with a hefty price tag. 2 photos.

  2. Blasting agent package

    Energy Technology Data Exchange (ETDEWEB)

    Fox, R.

    1971-03-17

    A protected preassembled package for blasting agents susceptible to desensitization by water consists of, in combination: (1) an inner rigid and self-supporting tube, the upper end of which is suited to be connected, or attached, to the discharge end of a loading hose for a blasting agent and the lower end of which is open; and (2) a flexible tubular liner made of water-resistant film, having a diameter greater than that of the inner tube and a length at least equal to the desired depth of its insertion into the borehole, the liner being sleeved over the length of the inner tube, the upper end of the liner being attached to the inner tube and the lower end of the liner being closed so as to prevent substantial discharge of the explosive mixture therefrom when the latter is pumped into it. (24 claims)

  3. Tunnel blasting - recent developments

    Energy Technology Data Exchange (ETDEWEB)

    White, T.E.

    1999-05-01

    While tunnelling machines are more efficient than previously, there are still areas where blasting is a more efficient method of advance. Drilling and design methods are increasingly sophisticated, as is choice of explosive. Explosive deployment must be carefully calculated so as to avoid desensitisation. Nitroglycerine may be used as slurries; bulk mixing on site of ANFO is also practised in mining in the UK. Electric detonators, Nonel tubes, and electronic detonators are also increasingly employed.

  4. Blasting technology advances

    Energy Technology Data Exchange (ETDEWEB)

    1990-04-01

    Nitroglycerine explosives are increasingly giving way to emulsions and low cost Anfo compositions, the latter sometimes incorporating emulsion in order to improve water resistance and performance. The aim is to produce an explosive which is extremely efficient, relatively safe and can be tailored to meet user requirements. Discussion is presented of emulsion delivery systems, initiation systems, electronic detonators, computer blast modelling, directional explosives, underground automation, and the development of Soviet explosives. 3 refs., 4 figs.

  5. Indian Vacuum Society: The Indian Vacuum Society

    Science.gov (United States)

    Saha, T. K.

    2008-03-01

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

  6. Numerical simulation of muzzle blast

    NARCIS (Netherlands)

    Tyler-Street, M.

    2014-01-01

    Structural design methods for naval ships include environmental, operational and military load cases. One of the operational loads acting on a typical naval vessel is the muzzle blast from a gun. Simulating the muzzle blast load acting on a ship structure with CFD and ALE methods leads to large

  7. Control blasting of reinforced concrete

    International Nuclear Information System (INIS)

    Nagase, Tetsuo

    1981-01-01

    With the need of decommissioning nuclear power plants, it is urgently required to establish its methods and standards. In Shimizu Construction Co., Ltd., experimental feasibility studies have been made on explosive demolition method i.e. the controlled blasting for the massive concrete structures peculiar to nuclear power plants, considering low radiation exposure, safety and high efficiency. As such, four techniques of line drilling, cushion blasting, pre-splitting and guide hole blasting, respectively, are described with photographs. Assuming the selective demolition of activated concrete structures, the series of experiments showed the good results of clear-cut surfaces and the effect of blasting was confined properly. Moreover, the scattering of debris in blasting was able to be entirely prevented by the use of rubber belts. The generation of gas and dust was also little due to the small amount of the charge used. (J.P.N.)

  8. NCBI BLAST+ integrated into Galaxy.

    Science.gov (United States)

    Cock, Peter J A; Chilton, John M; Grüning, Björn; Johnson, James E; Soranzo, Nicola

    2015-01-01

    The NCBI BLAST suite has become ubiquitous in modern molecular biology and is used for small tasks such as checking capillary sequencing results of single PCR products, genome annotation or even larger scale pan-genome analyses. For early adopters of the Galaxy web-based biomedical data analysis platform, integrating BLAST into Galaxy was a natural step for sequence comparison workflows. The command line NCBI BLAST+ tool suite was wrapped for use within Galaxy. Appropriate datatypes were defined as needed. The integration of the BLAST+ tool suite into Galaxy has the goal of making common BLAST tasks easy and advanced tasks possible. This project is an informal international collaborative effort, and is deployed and used on Galaxy servers worldwide. Several examples of applications are described here.

  9. Magnetically induced vacuum decay

    International Nuclear Information System (INIS)

    Xue Shesheng

    2003-01-01

    We study the fermionic vacuum energy of vacua with and without application of an external magnetic field. The energetic difference of two vacua leads to the vacuum decaying and the vacuum energy being released. In the context of quantum field theories, we discuss why and how the vacuum energy can be released by spontaneous photon emission and/or paramagnetically screening the external magnetic field. In addition, we quantitatively compute the vacuum energy released, the paramagnetic screening effect, and the rate and spectrum of spontaneous photon emission. The possibilities of experimentally detecting such an effect of vacuum-energy release and that this effect accounts for the anomalous x-ray pulsar are discussed

  10. Blast from the past

    Science.gov (United States)

    Carlowicz, Michael

    1996-02-01

    Forget dynamite or hydraulic and mechanical drills. Industrial and federal researchers have started boring holes with rocket fuel. In a cooperative arrangement between Sandia National Laboratory, Global Environmental Solutions, and Universal Tech Corp., scientists and engineers extracted fuel from 200 rocket motors and used it as a mining explosive. In a demonstration completed last fall, researchers used 4950 kg of solid rocket propellant to move more than 22,500 metric tons of rock from the Lone Star Quarry in Prairie, Oklahoma. They found that the fuel improved blast energy and detonation velocity over traditional explosives, and it required fewer drill holes.

  11. Trouble shooting problem blasts

    Energy Technology Data Exchange (ETDEWEB)

    Konya, K.D. [Society of Explosive Engineers, Montville, OH (United States)

    1996-02-01

    There have been many occurrences of water-gel or emulsion explosives or heavy Anfo`s (ammonium nitrate and fuel oil) either not detonating in some blast holes in surface coal mining operations, or producing yellow or reddish-brown fumes upon reaction. The explosives rely on entrapped gas to detonate properly. It is important to control the size of the bubble and the dispersion of gas bubbles throughout the explosive. The article discusses and compares the use of microspheres and of gassing agents for detonation control.

  12. Dismounted Complex Blast Injury.

    Science.gov (United States)

    Andersen, Romney C; Fleming, Mark; Forsberg, Jonathan A; Gordon, Wade T; Nanos, George P; Charlton, Michael T; Ficke, James R

    2012-01-01

    The severe Dismounted Complex Blast Injury (DCBI) is characterized by high-energy injuries to the bilateral lower extremities (usually proximal transfemoral amputations) and/or upper extremity (usually involving the non-dominant side), in addition to open pelvic injuries, genitourinary, and abdominal trauma. Initial resuscitation and multidisciplinary surgical management appear to be the keys to survival. Definitive treatment follows general principals of open wound management and includes decontamination through aggressive and frequent debridement, hemorrhage control, viable tissue preservation, and appropriate timing of wound closure. These devastating injuries are associated with paradoxically favorable survival rates, but associated injuries and higher amputation levels lead to more difficult reconstructive challenges.

  13. The use of computer blast simulations to improve blast quality

    International Nuclear Information System (INIS)

    Favreau, R.F.; Kuzyk, G.W.; Babulic, P.J.; Tienkamp, N.J.

    1989-01-01

    Atomic Energy of Canada Limited is constructing an Underground Research Laboratory (URL) as part of a comprehensive program to evaluate the concept of nuclear fuel waste disposal deep in crystalline rock formations. Careful blasting methods have been used to minimize damage to the excavation surfaces. Good wall quality is desirable in any excavation. In excavations required for nuclear waste disposal, the objective will be to minimize blast-induced fractures which may complicate the sealing requirements necessary to control subsequent movement of groundwater around a sealed disposal vault. The construction of the URL has provided an opportunity for the development of controlled blasting methods, especially for drilling accuracy and optimization of explosive loads in the perimeter and cushion holes. The work has been assisted by the use of blast simulations with the mathematical model Blaspa. This paper reviews the results of a recent project to develop a controlled method of full-face blasting, and compares the observed field results with the results of a blast simulator called Blaspa. Good agreement is found between the two, and the Blaspa results indicate quantitatively how the blasting may induce damage in the final excavation surface. In particular, the rock in the final wall may be stressed more severely by the cushion holes than by the perimeter holes. Bootleg of the rock between the perimeter and cushion rows occurs when the burst-out velocity imparted to it by the explosive loads in the perimeter holes is inadequate. In practice, these findings indicate that quantitative rock stress and rock burst-out velocity criteria can be established to minimize wall damage and bootleg. Thus, blast simulations become an efficient way to design controlled blasting and to optimize quality of the excavation surface

  14. Gravitation and vacuum field

    International Nuclear Information System (INIS)

    Tevikyan, R.V.

    1986-01-01

    This paper presents equations that describe particles with spins s = 0, 1/2, 1 completely and which also describe 2s + 2 limiting fields as E → ∞. It is shown that the ordinary Hilbert-Einstein action for the gravitation field must be augmented by the action for the Bose vacuum field. This means that one must introduce in the gravitational equations a cosmological term proportional to the square of the strength of the Bose vacuum field. It is shown that the theory of gravitation describes three realities: matter, field, and vacuum field. A new form of matter--the vacuum field--is introduced into field theory

  15. Centrifugal shot blast system

    International Nuclear Information System (INIS)

    1998-02-01

    This report describes a demonstration of Concrete cleaning, Inc., modified centrifugal shot blast technology to remove the paint coating from concrete flooring. This demonstration is part of the Chicago Pile-5 (CP-5) Large-Scale Demonstration Project (LSDP) sponsored by the US Department of Energy (DOE), office of Science and Technology (OST), Deactivation and Decommissioning Focus Area (DDFA). The objective of the LSDP is to select and demonstrate potentially beneficial technologies at the Argonne National Laboratory-East (ANL) CP-5 Research Reactor. The purpose of the LSDP is to demonstrate that using innovative and improved decontamination and decommissioning (D and D) technologies from various sources can result in significant benefits, such as decreased cost and increased health and safety, as compared with baseline D and D technologies. Potential markets exist for the innovative centrifugal shot blast system at the following sites: Fernald Environmental Management Project, Los Alamos, Nevada, Oak Ridge Y-12 and K-25, Paducah, Portsmouth Gaseous Diffusion site, and the Savannah River Site. This information is based on a revision to the OST Linkage Tables dated August 4, 1997

  16. CO2 pellet blasting studies

    International Nuclear Information System (INIS)

    Archibald, K.E.

    1997-01-01

    Initial tests with CO 2 pellet blasting as a decontamination technique were completed in 1993 at the Idaho Chemical Processing Plant (ICPP) at the Idaho National Engineering Laboratory (INEL). During 1996, a number of additional CO 2 pellet blasting studies with Alpheus Cleaning Technologies, Oak Ridge National Laboratory, and Pennsylvania State University were conducted. After the testing with Alpheus was complete, an SDI-5 shaved CO 2 blasting unit was purchased by the ICPP to test and determine its capabilities before using in ICPP decontamination efforts. Results of the 1996 testing will be presented in this report

  17. Insulation vacuum and beam vacuum overpressure release

    CERN Document Server

    Parma, V

    2009-01-01

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

  18. Modern vacuum physics

    CERN Document Server

    Chambers, Austin

    2005-01-01

    Modern Vacuum Physics presents the principles and practices of vacuum science and technology along with a number of applications in research and industrial production. The first half of the book builds a foundation in gases and vapors under rarefied conditions, The second half presents examples of the analysis of representative systems and describes some of the exciting developments in which vacuum plays an important role. The final chapter addresses practical matters, such as materials, components, and leak detection. Throughout the book, the author''s explanations are presented in terms of first principles and basic physics, augmented by illustrative worked examples and numerous figures.

  19. Evaporation under vacuum condition

    International Nuclear Information System (INIS)

    Mizuta, Satoshi; Shibata, Yuki; Yuki, Kazuhisa; Hashizume, Hidetoshi; Toda, Saburo; Takase, Kazuyuki; Akimoto, Hajime

    2000-01-01

    In nuclear fusion reactor design, an event of water coolant ingress into its vacuum vessel is now being considered as one of the most probable accidents. In this report, the evaporation under vacuum condition is evaluated by using the evaporation model we have developed. The results show that shock-wave by the evaporation occurs whose behavior strongly depends on the initial conditions of vacuum. And in the case of lower initial pressure and temperature, the surface temp finally becomes higher than other conditions. (author)

  20. Helical type vacuum container

    International Nuclear Information System (INIS)

    Owada, Kimio.

    1989-01-01

    Helical type vacuum containers in the prior art lack in considerations for thermal expansion stresses to helical coils, and there is a possibility of coil ruptures. The object of the present invention is to avoid the rupture of helical coils wound around the outer surface of a vacuum container against heat expansion if any. That is, bellows or heat expansion absorbing means are disposed to a cross section of a helical type vacuum container. With such a constitution, thermal expansion of helical coils per se due to temperature elevation of the coils during electric supply can be absorbed by expansion of the bellows or absorption of the heat expansion absorbing means. Further, this can be attained by arranging shear pins in the direction perpendicular to the bellows axis so that the bellows are not distorted when the helical coils are wound around the helical type vacuum container. (I.S.)

  1. Vacuum considerations: summary

    International Nuclear Information System (INIS)

    Blechschmidt, D.; Halama, H.J.

    1978-01-01

    A summary is given of the efforts of a vacuum systems study group of the workshop on a Heavy Ion Demonstration Experiment (HIDE) for heavy ion fusion. An inadequate knowledge of cross-sections prevents a more concrete vacuum system design. Experiments leading to trustworthy numbers for charge exchange, stripping and capture cross-sections are badly needed and should start as soon as possible. In linacs, beam loss will be almost directly proportional to the pressure inside the tanks. The tanks should, therefore, be built in such a way that they can be baked-out in situ to improve their vacuum, especially if the cross-sections turn out to be higher than anticipated. Using standard UHV techniques and existing pumps, an even lower pressure can be achieved. The vacuum system design for circular machines will be very difficult, and in some cases, beyond the present state-of-the-art

  2. Handbook of vacuum technology

    CERN Document Server

    2016-01-01

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

  3. Cold Vacuum Drying Facility

    Data.gov (United States)

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

  4. Vacuum mechatronics first international workshop

    Energy Technology Data Exchange (ETDEWEB)

    Belinski, S.E.; Shirazi, M.; Hackwood, S.; Beni, G. (eds.) (California Univ., Santa Barbara, CA (USA))

    1989-01-01

    This report contains papers on the following topics: proposed epitaxial thin film growth in the ultra-vacuum of space; particle monitoring and control in vacuum processing equipment; electrostatic dust collector for use in vacuum systems; materials evaluation of an electrically noisy vacuum slip ring assembly; an overview of lubrication and associated materials for vacuum service; the usage of lubricants in a vacuum environment; guidelines and practical applications for lubrication in vacuum; recent development in leak detector and calibrator designs; the durability of ballscrews for ultrahigh vacuum; vacuum-compatible robot for self-contained manufacturing systems; the design, fabrication, and assembly of an advanced vacuum robotics system for space payload calibration; design criteria for mechanisms used in space; and concepts and requirements for semiconductor multiprocess integration in vacuum. These papers are indexed separately elsewhere.

  5. TFTR diagnostic vacuum controller

    International Nuclear Information System (INIS)

    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

  6. Ultra high vacuum technology

    CERN Multimedia

    CERN. Geneva

    2001-01-01

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

  7. A Planck Vacuum Cosmology

    Directory of Open Access Journals (Sweden)

    Daywitt W. C.

    2009-04-01

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

  8. The use of computer blast simulations to improve blast quality

    International Nuclear Information System (INIS)

    Favreau, R.F.; Kuzzyk, G.W.; Babulic, P.J.; Morin, R.A.; Tienkamp, N.J.

    1987-01-01

    An underground research laboratory (URL) has been constructed as part of a comprehensive program to evaluate the concept of nuclear fuel waste disposal in deep crystalline rock formations. Careful blasting methods have been used to minimize damage to the excavation surfaces. This paper reviews the results of the program to develop controlled blasting for the full-face method, comparing the field observed results achieved with the simulated theoretical results. The simulated results indicate how the blasting may damage the excavation surface. Results suggest that the rock around the final wall is stressed more severely by the cushion holes than by the perimeter holes and that bootleg of the rock between the perimeter and cushion rows occurs when the burst-out velocity imparted to it by the explosive loads in the perimeter holes is inadequate

  9. Simulating geometrically complex blast scenarios

    Directory of Open Access Journals (Sweden)

    Ian G. Cullis

    2016-04-01

    Full Text Available The effects of blast waves generated by energetic and non-energetic sources are of continuing interest to the ballistics research community. Modern conflicts are increasingly characterised by asymmetric urban warfare, with improvised explosive devices (IEDs often playing a dominant role on the one hand and an armed forces requirement for minimal collateral effects from their weapons on the other. These problems are characterised by disparate length- and time-scales and may also be governed by complex physics. There is thus an increasing need to be able to rapidly assess and accurately predict the effects of energetic blast in topologically complex scenarios. To this end, this paper presents a new QinetiQ-developed advanced computational package called EAGLE-Blast, which is capable of accurately resolving the generation, propagation and interaction of blast waves around geometrically complex shapes such as vehicles and buildings. After a brief description of the numerical methodology, various blast scenario simulations are described and the results compared with experimental data to demonstrate the validation of the scheme and its ability to describe these complex scenarios accurately and efficiently. The paper concludes with a brief discussion on the use of the code in supporting the development of algorithms for fast running engineering models.

  10. Rock fragmentation control in opencast blasting

    Directory of Open Access Journals (Sweden)

    P.K. Singh

    2016-04-01

    Full Text Available The blasting operation plays a pivotal role in the overall economics of opencast mines. The blasting sub-system affects all the other associated sub-systems, i.e. loading, transport, crushing and milling operations. Fragmentation control through effective blast design and its effect on productivity are the challenging tasks for practicing blasting engineer due to inadequate knowledge of actual explosive energy released in the borehole, varying initiation practice in blast design and its effect on explosive energy release characteristic. This paper describes the result of a systematic study on the impact of blast design parameters on rock fragmentation at three mines in India. The mines use draglines and shovel–dumper combination for removal of overburden. Despite its pivotal role in controlling the overall economics of a mining operation, the expected blasting performance is often judged almost exclusively on the basis of poorly defined parameters such as powder factor and is often qualitative which results in very subjective assessment of blasting performance. Such an approach is very poor substitutes for accurate assessment of explosive and blasting performance. Ninety one blasts were conducted with varying blast designs and charging patterns, and their impacts on the rock fragmentation were documented. A high-speed camera was deployed to record the detonation sequences of the blasts. The efficiency of the loading machines was also correlated with the mean fragment size obtained from the fragmentation analyses.

  11. BLEVE blast by expansion-controlled evaporation

    NARCIS (Netherlands)

    Berg, A.C. van den; Voort, M.M. van der; Weerheijm, J.; Versloot, N.H.A.

    2006-01-01

    This report presents a new method to calculate the blast effects originating from an exploding vessel of liquefied gas. Adequate blast calculation requires full knowledge of the blast source characteristics, that is, the release and subsequent evaporation rate of the flashing liquid. Because the

  12. 30 CFR 75.1323 - Blasting circuits.

    Science.gov (United States)

    2010-07-01

    ...) Blasting circuits shall be protected from sources of stray electric current. (b) Detonators made by different manufacturers shall not be combined in the same blasting circuit. (c) Detonator leg wires shall be... used between the blasting cable and detonator circuitry shall— (1) Be undamaged; (2) Be well insulated...

  13. Organizações automatizadas - desenvolvimento e estrutura da empresa moderna. Nélio Oliveira. Rio de Janeiro: Editora LTC, 2007. 228p. ISBN: 8521614985.

    Directory of Open Access Journals (Sweden)

    Mauro de Paula Freitas Filho

    2007-06-01

    Full Text Available A Editora LTC lançou, em 2007, o livro de Nélio Oliveira, Organizações automatizadas: desenvolvimento e estrutura da empresa moderna. Mestre em Administração pela Universidade Federal de Minas Gerais, atuou durante anos em diversas organizações públicas, privadas e de economia mista. Nélio Oliveira, no momento atual, é conceituado professor dos cursos de Administração e Sistemas de Informações na Pontifícia Universidade Católica de Minas Gerais. No meio de muitas literaturas disponíveis, a obra destaca-se pela simplicidade, pela objetividade e pelo cuidado com os quais ele trata uma nova configuração, as organizações automatizadas. Em linhas gerais, o autor concentra-se em um trabalho descritivo e procura caracterizar um novo formato organizacional, o qual surge em muitas empresas, em substituição às formas anteriores, vinculadas a modelos mecanizados ou mecanísticos. A obra tem como foco o modelo de cinco estruturas de Henry Mintzberg, base para todo o trabalho. O autor tem como propósito retratar uma realidade, na qual se observam as mudanças do mundo organizacional contemporâneo, o qual está cada vez mais adquirindo espaço no mundo empresarial.

  14. Control buildings for blast resistance

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G.A.

    1982-08-01

    Offers advice on interior design for blast-resistant control buildings. Suggests that for the comfort and safety of occupants, special attention must be paid to internal finishes and color schemes. Considers external treatment (e.g. panels, cladding fixings, thermal insulation), air intakes and exhausts, internal finishes (e.g. stud lining method), and internal walls and partitions. Presents diagrams showing construction method for a control building; elimination of ''cold bridge'' at eaves level; staggering door openings to minimize blast effects; and flexure of concrete walls without affecting the inner lining.

  15. Porcine head response to blast.

    Science.gov (United States)

    Shridharani, Jay K; Wood, Garrett W; Panzer, Matthew B; Capehart, Bruce P; Nyein, Michelle K; Radovitzky, Raul A; Bass, Cameron R 'dale'

    2012-01-01

    Recent studies have shown an increase in the frequency of traumatic brain injuries related to blast exposure. However, the mechanisms that cause blast neurotrauma are unknown. Blast neurotrauma research using computational models has been one method to elucidate that response of the brain in blast, and to identify possible mechanical correlates of injury. However, model validation against experimental data is required to ensure that the model output is representative of in vivo biomechanical response. This study exposes porcine subjects to primary blast overpressures generated using a compressed-gas shock tube. Shock tube blasts were directed to the unprotected head of each animal while the lungs and thorax were protected using ballistic protective vests similar to those employed in theater. The test conditions ranged from 110 to 740 kPa peak incident overpressure with scaled durations from 1.3 to 6.9 ms and correspond approximately with a 50% injury risk for brain bleeding and apnea in a ferret model scaled to porcine exposure. Instrumentation was placed on the porcine head to measure bulk acceleration, pressure at the surface of the head, and pressure inside the cranial cavity. Immediately after the blast, 5 of the 20 animals tested were apneic. Three subjects recovered without intervention within 30 s and the remaining two recovered within 8 min following respiratory assistance and administration of the respiratory stimulant doxapram. Gross examination of the brain revealed no indication of bleeding. Intracranial pressures ranged from 80 to 390 kPa as a result of the blast and were notably lower than the shock tube reflected pressures of 300-2830 kPa, indicating pressure attenuation by the skull up to a factor of 8.4. Peak head accelerations were measured from 385 to 3845 G's and were well correlated with peak incident overpressure (R(2) = 0.90). One SD corridors for the surface pressure, intracranial pressure (ICP), and head acceleration are

  16. Water in the blast hole

    Energy Technology Data Exchange (ETDEWEB)

    Pilshaw, S.R. [Pilshaw Associates, KS (United States)

    1995-10-01

    Water in the blast area is a considerable problem in US opencast coal mining. While gelatin dynamite was reasonably water resistant, Anfo is not. All potential solutions to this problem: the use of Anfo and emulsion (Heavy Anfo), pumping, draining, and the use of water bags, involve considerable extra cost. With small amounts of water an alternative solution has been formulated: the use of a self inflating gas bag to exclude water, and loading the Anfo from the water line up to the stemming level of the blasthole. Quite substantial water columns may be sealed off in this manner, with little or no deleterious effect on blast effects.

  17. Vacuum arc anode phenomena

    International Nuclear Information System (INIS)

    Miller, H.C.

    1976-01-01

    A brief review of anode phenomena in vacuum arcs is presented. Discussed in succession are: the transition of the arc into the anode spot mode; the temperature of the anode before, during and after the anode spot forms; and anode ions. Characteristically the anode spot has a temperature of the order of the atmospheric boiling point of the anode material and is a copious source of vapor and energetic ions. The dominant mechanism controlling the transition of the vacuum arc into the anode spot mode appears to depend upon the electrode geometry, the electrode material, and the current waveform of the particular vacuum arc being considered. Either magnetic constriction in the gap plasma or gross anode melting can trigger the transition; indeed, a combination of the two is a common cause of anode spot formation

  18. Blast wave parameters at diminished ambient pressure

    Science.gov (United States)

    Silnikov, M. V.; Chernyshov, M. V.; Mikhaylin, A. I.

    2015-04-01

    Relation between blast wave parameters resulted from a condensed high explosive (HE) charge detonation and a surrounding gas (air) pressure has been studied. Blast wave pressure and impulse differences at compression and rarefaction phases, which traditionally determine damage explosive effect, has been analyzed. An initial pressure effect on a post-explosion quasi-static component of the blast load has been investigated. The analysis is based on empirical relations between blast parameters and non-dimensional similarity criteria. The results can be directly applied to flying vehicle (aircraft or spacecraft) blast safety analysis.

  19. Vacuum Arc Ion Sources

    CERN Document Server

    Brown, I.

    2013-12-16

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

  20. Vacuum fusion of uranium

    International Nuclear Information System (INIS)

    Stohr, J.A.

    1957-01-01

    After having outlined that vacuum fusion and moulding of uranium and of its alloys have some technical and economic benefits (vacuum operations avoid uranium oxidation and result in some purification; precision moulding avoids machining, chip production and chemical reprocessing of these chips; direct production of the desired shape is possible by precision moulding), this report presents the uranium fusion unit (its low pressure enclosure and pumping device, the crucible-mould assembly, and the MF supply device). The author describes the different steps of cast production, and briefly comments the obtained results

  1. Baryogenesis in false vacuum

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-09-15

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

  2. Vacuum considerations summary

    International Nuclear Information System (INIS)

    1977-01-01

    The vacuum system for Heavy Ion Fusion machines can be divided according to pressure into 4 parts: (a) Ion Sources; (b) Linear Accelerators; (c) Circular Accelerators, Accumulators and Storage Rings; and (d) Reactors. Since ion sources will need rather conventional pumping arrangements and reactors will operate with greater pressures, depending on their mode of operation, only items b and c will be treated in this report. In particular, the vacuum system design will be suggested for the machines proposed by various scenarios arrived at during the workshop. High mass numbers will be assumed

  3. Handbook of vacuum physics

    CERN Document Server

    1964-01-01

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

  4. Vacuum phonon tunneling.

    Science.gov (United States)

    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.

  5. Fragment Size Distribution of Blasted Rock Mass

    Science.gov (United States)

    Jug, Jasmin; Strelec, Stjepan; Gazdek, Mario; Kavur, Boris

    2017-12-01

    Rock mass is a heterogeneous material, and the heterogeneity of rock causes sizes distribution of fragmented rocks in blasting. Prediction of blasted rock mass fragmentation has a significant role in the overall economics of opencast mines. Blasting as primary fragmentation can significantly decrease the cost of loading, transport, crushing and milling operations. Blast fragmentation chiefly depends on the specific blast design (geometry of blast holes drilling, the quantity and class of explosive, the blasting form, the timing and partition, etc.) and on the properties of the rock mass (including the uniaxial compressive strength, the rock mass elastic Young modulus, the rock discontinuity characteristics and the rock density). Prediction and processing of blasting results researchers can accomplish by a variety of existing software’s and models, one of them is the Kuz-Ram model, which is possibly the most widely used approach to estimating fragmentation from blasting. This paper shows the estimation of fragmentation using the "SB" program, which was created by the authors. Mentioned program includes the Kuz-Ram model. Models of fragmentation are confirmed and calibrated by comparing the estimated fragmentation with actual post-blast fragmentation from image processing techniques. In this study, the Kuz-Ram fragmentation model has been used for an open-pit limestone quarry in Dalmatia, southern Croatia. The resulting calibrated value of the rock factor enables the quality prognosis of fragmentation in further blasting works, with changed drilling geometry and blast design parameters. It also facilitates simulation in the program to optimize blasting works and get the desired fragmentations of the blasted rock mass.

  6. NOBLAST and JAMBLAST: New Options for BLAST and a Java Application Manager for BLAST results.

    Science.gov (United States)

    Lagnel, Jacques; Tsigenopoulos, Costas S; Iliopoulos, Ioannis

    2009-03-15

    NOBLAST (New Options for BLAST) is an open source program that provides a new user-friendly tabular output format for various NCBI BLAST programs (Blastn, Blastp, Blastx, Tblastn, Tblastx, Mega BLAST and Psi BLAST) without any use of a parser and provides E-value correction in case of use of segmented BLAST database. JAMBLAST using the NOBLAST output allows the user to manage, view and filter the BLAST hits using a number of selection criteria. A distribution package of NOBLAST and JAMBLAST including detailed installation procedure is freely available from http://sourceforge.net/projects/JAMBLAST/ and http://sourceforge.net/projects/NOBLAST. Supplementary data are available at Bioinformatics online.

  7. LEP vacuum chamber, prototype

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

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

  8. Cryogenic vacuum pump design

    International Nuclear Information System (INIS)

    Bartlett, A.J.; Lessard, P.A.

    1984-01-01

    This paper is a review of the problems and tradeoffs involved in cryogenic vacuum pump analysis, design and manufacture. Particular attention is paid to the several issues unique to cryopumps, e.g., radiation loading, adsorption of noncondensible gases, and regeneration. A general algorithm for cryopump design is also proposed. 12 references

  9. ISR vacuum system

    CERN Multimedia

    CERN PhotoLab

    1971-01-01

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

  10. ISR vacuum system

    CERN Multimedia

    CERN PhotoLab

    1970-01-01

    A pressure of 5 x 10-11 Torr has been obtained repreatedly in this pilot section of the ISR vacuum system. The pilot section is 45 m long is pumped by 9 sputter-ion pumps pf 350 l/s pumping speed, and is baked out at 200 degrees C before each pump down.

  11. LEP Vacuum Chamber

    CERN Multimedia

    1983-01-01

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

  12. Vacuum distilling vessel

    Energy Technology Data Exchange (ETDEWEB)

    Reik, H

    1928-12-27

    Vacuum distilling vessel for mineral oil and the like, characterized by the ring-form or polyconal stiffeners arranged inside, suitably eccentric to the casing, being held at a distance from the casing by connecting members of such a height that in the resulting space if necessary can be arranged vapor-distributing pipes and a complete removal of the residue is possible.

  13. Scroll vacuum pump

    Energy Technology Data Exchange (ETDEWEB)

    Morishita, Etsuo; Suganami, Takuya; Nishida, Mitsuhiro; Kitora, Yoshihisa; Yamamoto, Sakuei; Fujii, Kosaburo

    1988-02-25

    An effort is made to apply a scroll machine to development of a vacuum pump. In view of mechanical simplification and load patterns, the vacuum pump uses a rotating mechanism to produce paired vortices rotating around each center. Chip seal and atmospheric pressure are utilized for axial gap sealing while a spring and atmospheric pressure for the radial gap sealing. In both gaps, the sealing direction is stationary relative to the environment during rotation, making it much easier to achieve effective sealing as compared to oscillating pumps. Since the compression ratio is high in vacuum pumps, a zero top clearance form is adopted for the central portion of vortices and an gas release valve is installed in the rotating axis. A compact Oldham coupling with a small inertia force is installed behind the vortices to maintain the required phase relations between the vortices. These improvements result in a vacuum of 1 Pa for dry operation and 10/sup -2/ Pa for oil flooded operation of a single-stage scroll machine at 1800 rpm. (5 figs, 1 tab, 4 refs)

  14. On Lovelock vacuum solution

    OpenAIRE

    Dadhich, Naresh

    2010-01-01

    We show that the asymptotic large $r$ limit of all Lovelock vacuum and electrovac solutions with $\\Lambda$ is always the Einstein solution in $d \\geq 2n+1$ dimensions. It is completely free of the order $n$ of the Lovelock polynomial indicating universal asymptotic behaviour.

  15. INCREASED RELIABILITY OF ELECTRIC BLASTING

    OpenAIRE

    Kashuba, Oleh Ivanovych; Skliarov, L I; Skliarov, A L

    2017-01-01

    The problems of improving reliability of an electric blasting method using electric detonators with nichrome filament bridges. It was revealed that in the calculation of the total resistance of the explosive network it is necessary to increase to 24% of the nominal value

  16. An analysis of the heap construction by long hole blasting for in-situ leaching of blasted ore

    International Nuclear Information System (INIS)

    Yang Shijiao

    1999-01-01

    The author establishes specific requirements for heap construction by blasting on the basis of the mechanism for in situ leaching of blasted ore, analyses the feasibility of heap construction by long hole blasting, selection of the blast plan and the relevant technological problems, and gives a case of heap construction by long hole blasting in Renhua uranium mine

  17. High current vacuum closing switch

    International Nuclear Information System (INIS)

    Dolgachev, G.I.; Maslennikov, D.D.; Romanov, A.S.; Ushakov, A.G.

    2005-01-01

    The paper proposes a powerful pulsed closing vacuum switch for high current commutation consisting of series of the vacuum diodes with near 1 mm gaps having closing time determined by the gaps shortening with the near-electrode plasmas [ru

  18. The symmetries of the vacuum

    International Nuclear Information System (INIS)

    Fleming, H.

    1985-01-01

    The vacuum equation of state required by cosmological inflation is taken seriously as a general property of the cosmological vacuum. This correctly restricts the class of theories which admit inflation. A model of such a vacuum is presented that leads naturally to the cosmological principle. (Author) [pt

  19. Nonperturbative QED vacuum birefringence

    Energy Technology Data Exchange (ETDEWEB)

    Denisov, V.I.; Dolgaya, E.E.; Sokolov, V.A. [Physics Department, Moscow State University,Moscow, 119991 (Russian Federation)

    2017-05-19

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

  20. Compact vacuum insulation embodiments

    Science.gov (United States)

    Benson, D.K.; Potter, T.F.

    1992-04-28

    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. 26 figs.

  1. Compact vacuum insulation

    Science.gov (United States)

    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.

  2. Dry vacuum pumps

    International Nuclear Information System (INIS)

    Sibuet, R

    2008-01-01

    For decades and for ultimate pressure below 1 mbar, oil-sealed Rotary Vane Pumps have been the most popular solution for a wide range of vacuum applications. In the late 80ies, Semiconductor Industry has initiated the development of the first dry roughing pumps. Today SC applications are only using dry pumps and dry pumping packages. Since that time, pumps manufacturers have developed dry vacuum pumps technologies in order to make them attractive for other applications. The trend to replace lubricated pumps by dry pumps is now spreading over many other market segments. For the Semiconductor Industry, it has been quite easy to understand the benefits of dry pumps, in terms of Cost of Ownership, process contamination and up-time. In this paper, Technology of Dry pumps, its application in R and D/industries, merits over conventional pumps and future growth scope will be discussed

  3. Temperature control in vacuum

    International Nuclear Information System (INIS)

    Dearnaley, G.

    1986-01-01

    The patent concerns a method for controlling the temperature of silicon wafers (or samples), during ion beam treatment of the wafers, in a vacuum. The apparatus and method are described for irradiation and temperature control of the samples. The wafers are mounted on a drum which is rotated through the ion beam, and are additionally heated by infra-red lamps to achieve the desired temperature. (U.K.)

  4. Electroweak vacuum geometry

    International Nuclear Information System (INIS)

    Lepora, N.; Kibble, T.

    1999-01-01

    We analyse symmetry breaking in the Weinberg-Salam model paying particular attention to the underlying geometry of the theory. In this context we find two natural metrics upon the vacuum manifold: an isotropic metric associated with the scalar sector, and a squashed metric associated with the gauge sector. Physically, the interplay between these metrics gives rise to many of the non-perturbative features of Weinberg-Salam theory. (author)

  5. Vacuum inhomogeneous cosmological models

    International Nuclear Information System (INIS)

    Hanquin, J.-L.

    1984-01-01

    The author presents some results concerning the vacuum cosmological models which admit a 2-dimensional Abelian group of isometries: classifications of these space-times based on the topological nature of their space-like hypersurfaces and on their time evolution, analysis of the asymptotical behaviours at spatial infinity for hyperbolical models as well as in the neighbourhood of the singularity for the models possessing a time singularity during their evolution. (Auth.)

  6. ELETTRA vacuum system

    International Nuclear Information System (INIS)

    Bernardini, M.; Daclon, F.; Giacuzzo, F.; Miertusova, J.; Pradal, F.; Kersevan, R.

    1993-01-01

    Elettra is a third-generation synchrotron light source which is being built especially for the use of high brilliance radiation from insertion devices and bending magnets. The UHV conditions in a storage ring lead to a longer beam lifetime - one of the most important criterion. The Elettra vacuum system presents some pecularities which cannot be found in any already existing machine. The final version of bending magnet vacuum chamber is presented. After chemical and thermal conditioning the specific outgassing rate of about 1.5e-12 Torr. liters sec -1 cm -2 was obtained. A microprocessor-controlled system has been developed to perform bake-out at the uniform temperature. The etched-foil type heaters are glued to the chamber and Microtherm insulation is used. UHV pumps based on standard triode sputter-ion pumps were modified with ST 707 NEG (Non Evaporable Getter) modules. A special installation enables the resistive activation of getters and significantly increases pumping speed for hydrogen and other residual gases (except methane and argon). All these technological innovations improve vacuum conditions in Elettra storage ring and consequently also the other parameters of the light source

  7. PARAFFIN SEPARATION VACUUM DISTILLATION

    Directory of Open Access Journals (Sweden)

    Zaid A. Abdulrahman

    2013-05-01

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

  8. Vacuum system for LHC

    International Nuclear Information System (INIS)

    Groebner, O.

    1995-01-01

    The Large Hadron Collider (LHC) which is planned at CERN will be housed in the tunnel of the Large Electron Positron collider (LEP) and will store two counter-rotating proton beams with energies of up to 7 TeV in a 27 km accelerator/storage ring with superconducting magnets. The vacuum system for the LHC will be at cryogenic temperatures (between 1.9 and 20 K) and will be exposed to synchrotron radiation emitted by the protons. A stringent limitation on the vacuum is given by the energy deposition in the superconducting coils of the magnets due to nuclear scattering of the protons on residual gas molecules because this may provoke a quench. This effect imposes an upper limit to a local region of increased gas density (e.g. a leak), while considerations of beam lifetime (100 h) will determine more stringent requirements on the average gas density. The proton beam creates ions from the residual gas which may strike the vacuum chamber with sufficient energy to lead to a pressure 'run-away' when the net ion induced desorption yield exceeds a stable limit. These dynamic pressure effects will be limited to an acceptable level by installing a perforated 'beam screen' which shields the cryopumped gas molecules at 1.9 K from synchrotron radiation and which also absorbs the synchrotron radiation power at a higher and, therefore, thermodynamically more efficient temperature. (author)

  9. Anomalous vacuum expectation values

    International Nuclear Information System (INIS)

    Suzuki, H.

    1986-01-01

    The anomalous vacuum expectation value is defined as the expectation value of a quantity that vanishes by means of the field equations. Although this value is expected to vanish in quantum systems, regularization in general produces a finite value of this quantity. Calculation of this anomalous vacuum expectation value can be carried out in the general framework of field theory. The result is derived by subtraction of divergences and by zeta-function regularization. Various anomalies are included in these anomalous vacuum expectation values. This method is useful for deriving not only the conformal, chiral, and gravitational anomalies but also the supercurrent anomaly. The supercurrent anomaly is obtained in the case of N = 1 supersymmetric Yang-Mills theory in four, six, and ten dimensions. The original form of the energy-momentum tensor and the supercurrent have anomalies in their conservation laws. But the modification of these quantities to be equivalent to the original one on-shell causes no anomaly in their conservation laws and gives rise to anomalous traces

  10. Blast-Induced Acceleration in a Shock Tube: Distinguishing Primary and Tertiary Blast Injury

    Science.gov (United States)

    2016-10-01

    injury conditions (blast and acceleration vs acceleration alone) undergo neurobehavioral and histopathological assessments to comprehensively... reversal . To facilitate mid-air blasts, a release mechanism was devised. Balls were attached to the bail of the mechanism. The blast wave would cause

  11. CrocoBLAST: Running BLAST efficiently in the age of next-generation sequencing.

    Science.gov (United States)

    Tristão Ramos, Ravi José; de Azevedo Martins, Allan Cézar; da Silva Delgado, Gabrielle; Ionescu, Crina-Maria; Ürményi, Turán Peter; Silva, Rosane; Koca, Jaroslav

    2017-11-15

    CrocoBLAST is a tool for dramatically speeding up BLAST+ execution on any computer. Alignments that would take days or weeks with NCBI BLAST+ can be run overnight with CrocoBLAST. Additionally, CrocoBLAST provides features critical for NGS data analysis, including: results identical to those of BLAST+; compatibility with any BLAST+ version; real-time information regarding calculation progress and remaining run time; access to partial alignment results; queueing, pausing, and resuming BLAST+ calculations without information loss. CrocoBLAST is freely available online, with ample documentation (webchem.ncbr.muni.cz/Platform/App/CrocoBLAST). No installation or user registration is required. CrocoBLAST is implemented in C, while the graphical user interface is implemented in Java. CrocoBLAST is supported under Linux and Windows, and can be run under Mac OS X in a Linux virtual machine. jkoca@ceitec.cz. Supplementary data are available at Bioinformatics online. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

  12. Vacuum pumping concepts for ETF

    International Nuclear Information System (INIS)

    Homeyer, W.G.

    1980-09-01

    The Engineering Test Facility (ETF) poses unique vacuum pumping requirements due to its large size and long burn characteristics. These requirements include torus vacuum pumping initially and between burns and pumping of neutralized gas from divertor collector chambers. It was found that the requirements could be met by compound cryopumps in which molecular sieve 5A is used as the cryosorbent. The pumps, ducts, and vacuum valves required are large but fit with other ETF components and do not require major advances in vacuum pumping technology. Several additional design, analytical, and experimental studies were identified as needed to optimize designs and provide better design definition for the ETF vacuum pumping systems

  13. Human Injury Criteria for Underwater Blasts.

    Directory of Open Access Journals (Sweden)

    Rachel M Lance

    Full Text Available Underwater blasts propagate further and injure more readily than equivalent air blasts. Development of effective personal protection and countermeasures, however, requires knowledge of the currently unknown human tolerance to underwater blast. Current guidelines for prevention of underwater blast injury are not based on any organized injury risk assessment, human data or experimental data. The goal of this study was to derive injury risk assessments for underwater blast using well-characterized human underwater blast exposures in the open literature. The human injury dataset was compiled using 34 case reports on underwater blast exposure to 475 personnel, dating as early as 1916. Using severity ratings, computational reconstructions of the blasts, and survival information from a final set of 262 human exposures, injury risk models were developed for both injury severity and risk of fatality as functions of blast impulse and blast peak overpressure. Based on these human data, we found that the 50% risk of fatality from underwater blast occurred at 302±16 kPa-ms impulse. Conservatively, there is a 20% risk of pulmonary injury at a kilometer from a 20 kg charge. From a clinical point of view, this new injury risk model emphasizes the large distances possible for potential pulmonary and gut injuries in water compared with air. This risk value is the first impulse-based fatality risk calculated from human data. The large-scale inconsistency between the blast exposures in the case reports and the guidelines available in the literature prior to this study further underscored the need for this new guideline derived from the unique dataset of actual injuries in this study.

  14. Alkaline carbonates in blast furnace process

    Directory of Open Access Journals (Sweden)

    P. Besta

    2014-10-01

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

  15. Interspecies Scaling in Blast Neurotrauma

    Science.gov (United States)

    2015-08-27

    and services to assist recovery . Santa Monica, CA: Rand Corporation. Taylor, PA and Ford, CC. 2009. "Simulation of Blast-Induced Early-Time...reducing this burden, to Washington Headquarters Services , Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite... Warden 2006). As of 2008 it was estimated that approximately 19% or 320,000 OIF/OEF veterans had sustained a TBI (Tanielian et al. 2008). In 2011 a

  16. Water in blast holes can improve blasting efficiency and cut costs

    Energy Technology Data Exchange (ETDEWEB)

    O' Regan, G.

    1983-08-01

    Water in blast holes has been a traditional problem faced by blasting engineers and foremen in surface mining. Presently accepted techniques for blasting in water-filled holes include the use of more expensive water-gel explosives which are denser than water, dewatering of holes by pumping, and blowing out the water with a small charge before loading the main ANFO charge column. These methods involve considerable expense and delay to the normal charge-loading procedure. The author describes a method of using the water in blast holes to improve blasting efficiency and reduce the consumption of explosive.

  17. The vacuum platform

    Science.gov (United States)

    McNab, A.

    2017-10-01

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

  18. R&D ERL: Vacuum

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-01-01

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

  19. R and D ERL: Vacuum

    International Nuclear Information System (INIS)

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

    2010-01-01

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

  20. Changing MFTF vacuum environment

    International Nuclear Information System (INIS)

    Margolies, D.; Valby, L.

    1982-12-01

    The Mirror Fusion Test Facility (MFTF) vacuum vessel will be about 60m long and 10m in diameter at the widest point. The allowable operating densities range from 2 x 10 9 to 5 x 10 10 particles per cc. The maximum leak rate of 10 - 6 tl/sec is dominated during operation by the deliberately injected cold gas of 250 tl/sec. This gas is pumped by over 1000 square meters of cryopanels, external sorption pumps and getters. The design and requirements have changed radically over the past several years, and they are still not in final form. The vacuum system design has also changed, but more slowly and less radically. This paper discusses the engineering effort necessary to meet these stringent and changing requirements. Much of the analysis of the internal systems has been carried out using a 3-D Monte Carlo computer code, which can estimate time dependent operational pressures. This code and its use will also be described

  1. Of vacuum and gas

    CERN Multimedia

    Katarina Anthony

    2015-01-01

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

  2. LHC vacuum system

    CERN Document Server

    Gröbner, Oswald

    1999-01-01

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

  3. The use of blast furnace slag

    Directory of Open Access Journals (Sweden)

    V. Václavík

    2012-10-01

    Full Text Available The paper presents the results of experimental research that dealt with the substitution of finely ground blast furnace slag for Portland cement in the course of simple concrete manufacturing. Physical and mechanical properties of experimental concrete mixtures based on finely ground blast furnace slag were observed.

  4. Blast mitigation experimental and numerical studies

    CERN Document Server

    2013-01-01

    Presents experimental methods of material and structural response to dynamic blast loads Includes computational analysis of material and structural response to dynamic blast loads Offers mitigation measures for structures in various environments Relates lab experiments to larger field tests Features more than 150 illustrations

  5. Blast resistance behaviour of steel frame structrures

    NARCIS (Netherlands)

    Mediavilla Varas, J.; Soetens, F.

    2010-01-01

    The effect of a blast explosion on a typical steel frame building is investigated by means of computer simulations. The simulations help to identify possible hot spots that may lead to local or global failure. Since the blast energy is transferred to the structure by means of the façade, it is

  6. Blast resistance behaviour of steel frame structures

    NARCIS (Netherlands)

    Varas, J.M.; Soetens, F.

    2010-01-01

    The effect of a blast explosion on a typical steel frame building is investigated by means of computer simulations. The simulations help to identify possible hot spots that may lead to local or global failure. The blast energy is transferred to the structure by means of the façade. In particular

  7. 30 CFR 56.6312 - Secondary blasting.

    Science.gov (United States)

    2010-07-01

    ... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Use § 56.6312 Secondary blasting. Secondary blasts fired at the same time in the same work area shall be initiated from...

  8. Particle contamination in vacuum systems

    International Nuclear Information System (INIS)

    Martignac, J.; Bonin, B.; Henriot, C.; Poupeau, J.P.; Koltchakian, I.; Kocic, D.; Herbeaux, Ch.; Marx, J.P.

    1996-01-01

    Many vacuum devices, like RF cavities, are sensitive to particle contamination. This fact has motivated a considerable effort of cleanliness from the SRF community. The present paper reports the first results of a general study trying to identify the most contaminating steps during assembly and vacuum operation of the cavity. The steps investigated here are gasket assembly, evacuation and venting of the vacuum system, and operation of sputter ion pumps. (author)

  9. Vacuum guidelines for ISA insertions

    International Nuclear Information System (INIS)

    Edwards, D. Jr.

    1976-01-01

    Vacuum requirements place design restrictions on the ISA insertions. The vacuum tube diameter, given a distance L between pumps, is determined by the desorption of molecules from the wall under the impact of ions created by the beam, whereas the thickness of the tube must be sufficient to prevent collapse. In addition, the entire vacuum chamber must be able to be baked out at approximately 200 0 C

  10. Particle contamination in vacuum systems

    International Nuclear Information System (INIS)

    Martignac, J.; Bonin, B.; Henriot, C.; Poupeau, J.P.; Koltchakian, I.; Kocic, D.; Herbeaux, Ch.; Marx, J.P.

    1996-01-01

    Many vacuum devices, like RF cavities, are sensitive to particle contamination. This fact has motivated a considerable effort of cleanliness from the SRF community. The first results of a general study trying to identify the most contaminating steps during assembly and vacuum operation of the cavity is reported. The steps investigated here are gasket assembly, evacuation and venting of the vacuum system, and operation of sputter ion pumps. (author)

  11. Big Bang or vacuum fluctuation

    International Nuclear Information System (INIS)

    Zel'dovich, Ya.B.

    1980-01-01

    Some general properties of vacuum fluctuations in quantum field theory are described. The connection between the ''energy dominance'' of the energy density of vacuum fluctuations in curved space-time and the presence of singularity is discussed. It is pointed out that a de-Sitter space-time (with the energy density of the vacuum fluctuations in the Einstein equations) that matches the expanding Friedman solution may describe the history of the Universe before the Big Bang. (P.L.)

  12. Vacuum metastability with black holes

    Energy Technology Data Exchange (ETDEWEB)

    Burda, Philipp [Centre for Particle Theory, Durham University,South Road, Durham, DH1 3LE (United Kingdom); Gregory, Ruth [Centre for Particle Theory, Durham University,South Road, Durham, DH1 3LE (United Kingdom); Perimeter Institute, 31 Caroline Street North,Waterloo, ON, N2L 2Y5 (Canada); Moss, Ian G. annd [School of Mathematics and Statistics, Newcastle University,Newcastle Upon Tyne, NE1 7RU (United Kingdom)

    2015-08-24

    We consider the possibility that small black holes can act as nucleation seeds for the decay of a metastable vacuum, focussing particularly on the Higgs potential. Using a thin-wall bubble approximation for the nucleation process, which is possible when generic quantum gravity corrections are added to the Higgs potential, we show that primordial black holes can stimulate vacuum decay. We demonstrate that for suitable parameter ranges, the vacuum decay process dominates over the Hawking evaporation process. Finally, we comment on the application of these results to vacuum decay seeded by black holes produced in particle collisions.

  13. Vacuum metastability with black holes

    International Nuclear Information System (INIS)

    Burda, Philipp; Gregory, Ruth; Moss, Ian G. annd

    2015-01-01

    We consider the possibility that small black holes can act as nucleation seeds for the decay of a metastable vacuum, focussing particularly on the Higgs potential. Using a thin-wall bubble approximation for the nucleation process, which is possible when generic quantum gravity corrections are added to the Higgs potential, we show that primordial black holes can stimulate vacuum decay. We demonstrate that for suitable parameter ranges, the vacuum decay process dominates over the Hawking evaporation process. Finally, we comment on the application of these results to vacuum decay seeded by black holes produced in particle collisions.

  14. PDX vacuum vessel stress analysis

    International Nuclear Information System (INIS)

    Nikodem, Z.D.

    1975-01-01

    A stress analysis of PDX vacuum vessel is described and the summary of results is presented. The vacuum vessel is treated as a toroidal shell of revolution subjected to an internal vacuum. The critical buckling pressure is calculated. The effects of the geometrical discontinuity at the juncture of toroidal shell head and cylindrical outside wall, and the concavity of the cylindrical wall are examined. An effect of the poloidal field coil supports and the vessel outside supports on the stress distribution in the vacuum vessel is determined. A method evaluating the influence of circular ports in the vessel wall on the stress level in the vessel is outlined

  15. Vacuum leak detector and method

    Science.gov (United States)

    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.

  16. Vacuum science, technology, and applications

    CERN Document Server

    Naik, Pramod K

    2018-01-01

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

  17. Surge-damping vacuum valve

    International Nuclear Information System (INIS)

    Bullock, J.C.; Kelley, B.E.

    1977-01-01

    A valve for damping out flow surges in a vacuum system is described. The surge-damping mechanism consists of a slotted, spring-loaded disk adjacent to the valve's vacuum port (the flow passage to the vacuum roughing pump). Under flow surge conditions, the differential pressure forces the disk into a sealing engagement with the vacuum port, thereby restricting the gas flow path to narrow slots in the disk's periphery. The increased flow damps out the flow surge. When pressure is equalized on both sides of the valve, the spring load moves the disk away from the port to restore full flow conductance through the valve

  18. Shiva and Argus target diagnostics vacuum systems

    International Nuclear Information System (INIS)

    Glaros, S.S.; Mayo, S.E.; Campbell, D.; Holeman, D.

    1978-09-01

    The normal operation of LLL's Argus and Shiva laser irradiation facilities demand a main vacuum system for the target chamber and a separate local vacuum system for each of the larger appendage dianostics. This paper will describe the Argus and Shiva main vacuum systems, their respective auxiliary vacuum systems and the individual diagnostics with their respective special vacuum requirements and subsequent vacuum systems. Our latest approach to automatic computer-controlled vacuum systems will be presented

  19. Condition for Contur Blasting use on Openpit Mines

    OpenAIRE

    Krsmanovic, I; Dambov, Risto

    2010-01-01

    For purpose of obtaining a stable final slope in open pit mines practice, the most common approach is the contour blasting method and investigation of possible applications of various primary blasting methods for purpose of gaining the optimal techno-economical effects. This paper presents one of the contour blasting methods, drilling and blasting parameters, construction of explosive charges and method of initiation.

  20. 30 CFR 780.13 - Operation plan: Blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Operation plan: Blasting. 780.13 Section 780.13... SURFACE MINING PERMIT APPLICATIONS-MINIMUM REQUIREMENTS FOR RECLAMATION AND OPERATION PLAN § 780.13 Operation plan: Blasting. (a) Blasting plan. Each application shall contain a blasting plan for the proposed...

  1. Melting the vacuum

    International Nuclear Information System (INIS)

    Rafelski, J.

    1998-01-01

    Results presented at the Quark Matter 97 conference, held in December in Tsukuba, Japan, have provided new insights into the confinement of quarks in matter. The current physics paradigm is that the inertial masses of protons and neutrons, and hence of practically all of the matter around us, originate in the zero-point energy caused by the confinement of quarks inside the small volume of the nucleon. Today, 25 years after Harald Fritzsch, Heinrich Leutwyler and Murray Gell-Mann proposed quantum chromodynamics (QCD) as a means for understanding strongly interacting particles such as nucleons and mesons, our understanding of strong interactions and quark confinement remains incomplete. Quarks and the gluons that bind them together have a ''colour'' charge that may be red, green or blue. But quarks are seen in particles that are white: baryons such as protons and neutrons consist of three quarks with different colour charges, while mesons consist of a quark and an antiquark, and again the colour charge cancels out. To prove that confinement arises from quark-gluon fluctuations in the vacuum that quantum theories dictate exists today, we need to find a way of freeing the colour charge of quarks. Experiments must therefore ''melt'' the vacuum to deconfine quarks and the colour charge. By colliding nuclei at high energies, we hope to produce regions of space filled with free quarks and gluons. This deconfined phase is known as the quark-gluon plasma. At the Tsukuba meeting, Scott Pratt of Michigan State University in the US discussed measurements that show that the hot dense state of matter created in these collisions exists for only 2x10 -23 s. So does the quark gluon plasma exist? No-one doubts that it did at one time, before the vacuum froze into its current state about 20 into the life of the universe, causing the nucleons to form as we know them today. The issue is whether we can recreate this early stage of the universe in laboratory experiments. And if we did

  2. Anorectal injury in pelvic blast.

    Science.gov (United States)

    Brogden, Tom G; Garner, J P

    2013-03-01

    The signature injury of the Afghanistan campaign has, amongst other things, included an increased incidence of destructive anorectal injury. There is no significant body of evidence about this type of injury on which to base management strategies. This review examines the historical military data, later civilian reports, many of which have challenged the military dogmas of Vietnam, and the spartan contemporaneous military data which does not particularly address pelviperineal blast injury. There is no evidence to support a move away from the doctrine of the four D's (diversion, distal washout, drainage and direct repair), but sound surgical judgement remains the mainstay of managing these challenging and highly morbid injuries.

  3. Accelerator vacuum system elements

    International Nuclear Information System (INIS)

    Sivokon', V.V.; Kobets, A.F.; Shvetsov, V.A.; Sivokon', L.V.

    1980-01-01

    Some elements of vacuum systems are investigated. Considerable attention has been given to the investigation into peculiarities in pumping out of a ionoguide for transportation of an accelerated charged particles beam the spread of which often attains a considerable length. The number of pumps over the ionoguide length is experimentally determined. It is shown that as a result of ionoguide warm-up the pumping out time is considerably reduced maximum permissible pressure is decreased by two orders and lesser rate of pump pumping out is required. The investigations have shown that when operating the ionoguide there is no necessity in setting up seals between the ionoguide and magnetodischarged pump. The causes of the phenomenon in which the pressure near the pump is greater than in the end of the ionoguide, are impurities carried in by the pump into the ionoguide volume and the pumping out capacity of the pressure converter

  4. Vacuum strings in FRW models

    Energy Technology Data Exchange (ETDEWEB)

    Dyer, C C; Oattes, L M; Starkman, G D

    1988-01-01

    The authors find that vacuum string solutions cannot be embedded in an FRW model in the spirit of the swiss cheese model for inhomogeneities. Since all standard lensing calculations rely implicitly on the Swiss Cheese model, this result indicates that the previous lensing results for the vacuum string may be in error.

  5. The realm of the vacuum

    International Nuclear Information System (INIS)

    Buchholz, D.; Wanzenberg, R.

    1992-01-01

    The spacelike asymptotic structure of physical states in local quantum theory is analysed. It is shown that this structure can be described in terms of a vacuum state if the theory satisfies a condition of timelike asymptotic abelianess. Theories which violate this condition can have an involved asymptotic vacuum structure as is illustrated by a simple example. (orig.)

  6. Vacuum Technology for Ion Sources

    International Nuclear Information System (INIS)

    Chiggiato, P

    2013-01-01

    The basic notions of vacuum technology for ion sources are presented, with emphasis on pressure profile calculation and choice of pumping technique. A Monte Carlo code (Molflow+) for the evaluation of conductances and the vacuum-electrical analogy for the calculation of time-dependent pressure variations are introduced. The specific case of the Linac4 H - source is reviewed. (author)

  7. ULTRARAPID VACUUM-MICROWAVE HISTOPROCESSING

    NARCIS (Netherlands)

    KOK, LP; BOON, ME

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

  8. Detecting leaks in vacuum bags

    Science.gov (United States)

    Carlstrom, E. E.

    1980-01-01

    Small leaks in vacuum bag can be readily detected by eye, using simple chemical reaction: combination of ammonia and acetic acid vapors to produce cloudy white smoke. Technique has been successfully used to test seam integrity and to identify minute pinholes in vacuum bag used in assembly of ceramic-tile heat shield for Space Shuttle Orbiter.

  9. Vacuum Technology for Superconducting Devices

    Energy Technology Data Exchange (ETDEWEB)

    Chiggiato, P [European Organization for Nuclear Research, Geneva (Switzerland)

    2014-07-01

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

  10. Vacuum Alignment with more Flavors

    DEFF Research Database (Denmark)

    Ryttov, Thomas

    2014-01-01

    We study the alignment of the vacuum in gauge theories with $N_f$ Dirac fermions transforming according to a complex representation of the gauge group. The alignment of the vacuum is produced by adding a small mass perturbation to the theory. We study in detail the $N_f=2,3$ and $4$ case. For $N_...

  11. The AGS Booster vacuum systems

    International Nuclear Information System (INIS)

    Hseuh, H.C.

    1989-01-01

    The AGS Booster is a synchrotron for the acceleration of both protons and heavy ions. The design pressure of low 10 -11 mbar is required to minimize beam loss of the partially stripped heavy ions. To remove contaminants and to reduce outgassing, the vacuum chambers and the components located in them will be chemically cleaned, vacuum fired, baked then treated with nitric oxide. The vacuum sector will be insitu baked to a minimum of 200 degree C and pumped by the combination of sputter ion pumps and titanium sublimation pumps. This paper describes the design and the processing of this ultra high vacuum system, and the performance of some half-cell vacuum chambers. 9 refs., 7 figs

  12. Cosmology with decaying vacuum energy

    International Nuclear Information System (INIS)

    Freese, K.; Adams, F.; Frieman, J.; Mottola, E.

    1987-09-01

    Motivated by recent attempts to solve the cosmological constant problem, we examine the observational consequences of a vacuum energy density which decays in time. For all times later than t ∼ 1 sec, the ratio of the vacuum to the total energy density of the universe must be small. Although the vacuum cannot provide the ''missing mass'' required to close the universe today, its presence earlier in the history of the universe could have important consequences. We discuss restrictions on the vacuum energy arising from primordial nucleosynthesis, the microwave and gamma ray background spectra, and galaxy formation. A small vacuum component at the era of nucleosynthesis, 0.01 5, but in some cases would severely distort the microwave spectrum. 9 refs., 3 figs

  13. Vacuum transitions in dual models

    International Nuclear Information System (INIS)

    Pashnev, A.I.; Volkov, D.V.; Zheltukhin, A.A.

    1976-01-01

    The investigation is continued of the spontaneous vacuum transition problem in the Neview-Schwartz dual model (NSDM). It is shown that vacuum transitions allow disclosing of supplementary degeneration in the resonance state spectrum. The dual amplitudes possess an internal structure corresponding to the presence of an infinite number of quarks with increasing masses and retained charges. The Adler principle holds. Analytic continuation on the constant of induced vacuum transitions makes it possible to establish the existence of spontaneous vacuum transitions in the NSDM. The consequence of this fact is the exact SU(2) symmetry of π, rho meson trajectories and the Higgs mechanism in the model. In this case the ratios of masses of particles leading trajectories are analogous to those obtained in the current algebra. It is shown that in the NSDM there arises chiral SU(2) x SU(2) x U(1) x U(1) x ... symmetry resulting from spontaneous vacuum transitions

  14. Hadron Contribution to Vacuum Polarisation

    CERN Document Server

    Davier, M; Malaescu, B; Zhang, Z

    2016-01-01

    Precision tests of the Standard Theory require theoretical predictions taking into account higher-order quantum corrections. Among these vacuum polarisation plays a predominant role. Vacuum polarisation originates from creation and annihilation of virtual particle–antiparticle states. Leptonic vacuum polarisation can be computed from quantum electrodynamics. Hadronic vacuum polarisation cannot because of the non-perturbative nature of QCD at low energy. The problem is remedied by establishing dispersion relations involving experimental data on the cross section for e+ e− annihilation into hadrons. This chapter sets the theoretical and experimental scene and reviews the progress achieved in the last decades thanks to more precise and complete data sets. Among the various applications of hadronic vacuum polarisation calculations, two are emphasised: the contribution to the anomalous magnetic moment of the muon, and the running of the fine structure constant α to the Z mass scale. They are fundamental ingre...

  15. Primary blast survival and injury risk assessment for repeated blast exposures.

    Science.gov (United States)

    Panzer, Matthew B; Bass, Cameron R Dale; Rafaels, Karin A; Shridharani, Jay; Capehart, Bruce P

    2012-02-01

    The widespread use of explosives by modern insurgents and terrorists has increased the potential frequency of blast exposure in soldiers and civilians. This growing threat highlights the importance of understanding and evaluating blast injury risk and the increase of injury risk from exposure to repeated blast effects. Data from more than 3,250 large animal experiments were collected from studies focusing on the effects of blast exposure. The current study uses 2,349 experiments from the data collection for analysis of the primary blast injury and survival risk for both long- and short-duration blasts, including the effects from repeated exposures. A piecewise linear logistic regression was performed on the data to develop survival and injury risk assessment curves. New injury risk assessment curves uniting long- and short-duration blasts were developed for incident and reflected pressure measures and were used to evaluate the risk of injury based on blast over pressure, positive-phase duration, and the number of repeated exposures. The risk assessments were derived for three levels of injury severity: nonauditory, pulmonary, and fatality. The analysis showed a marked initial decrease in injury tolerance with each subsequent blast exposure. This effect decreases with increasing number of blast exposures. The new injury risk functions showed good agreement with the existing experimental data and provided a simplified model for primary blast injury risk. This model can be used to predict blast injury or fatality risk for single exposure and repeated exposure cases and has application in modern combat scenarios or in setting occupational health limits. .Copyright © 2012 by Lippincott Williams & Wilkins

  16. A Blast Wave Model With Viscous Corrections

    Science.gov (United States)

    Yang, Z.; Fries, R. J.

    2017-04-01

    Hadronic observables in the final stage of heavy ion collision can be described well by fluid dynamics or blast wave parameterizations. We improve existing blast wave models by adding shear viscous corrections to the particle distributions in the Navier-Stokes approximation. The specific shear viscosity η/s of a hadron gas at the freeze-out temperature is a new parameter in this model. We extract the blast wave parameters with viscous corrections from experimental data which leads to constraints on the specific shear viscosity at kinetic freeze-out. Preliminary results show η/s is rather small.

  17. Behavior of coke in large blast furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, N

    1978-01-01

    Three blast furnaces were quenched in operation and the contents were examined; the temperature distribution was also measured, using Tempil pellets. The furnaces examined included a low productivity one, which was examined to see what was wrong. Changes in the quality of coke as it descends in the furnace, and coke behavior in the raceway and hearth are reported. The functions required of coke, and the effects of poor coke quality, are explained, together with the coke quality required in large blast furnaces. A theoretical study of the role of coke in large blast furnaces is included.

  18. A Blast Wave Model With Viscous Corrections

    International Nuclear Information System (INIS)

    Yang, Z; Fries, R J

    2017-01-01

    Hadronic observables in the final stage of heavy ion collision can be described well by fluid dynamics or blast wave parameterizations. We improve existing blast wave models by adding shear viscous corrections to the particle distributions in the Navier-Stokes approximation. The specific shear viscosity η/s of a hadron gas at the freeze-out temperature is a new parameter in this model. We extract the blast wave parameters with viscous corrections from experimental data which leads to constraints on the specific shear viscosity at kinetic freeze-out. Preliminary results show η/s is rather small. (paper)

  19. Blast casting requires fresh assessment of methods

    Energy Technology Data Exchange (ETDEWEB)

    Pilshaw, S.R.

    1987-08-01

    The article discusses the reasons why conventional blasting operations, mainly that of explosive products, drilling and initiation methods are inefficient, and suggests new methods and materials to overcome the problems of the conventional operations. The author suggests that the use of bulk ANFO for casting, instead of high energy and density explosives with high velocity detonation is more effective in producing heave action results. Similarly the drilling of smaller blast holes than is conventional allows better loading distribution of explosives in the rock mass. The author also suggests that casting would be more efficient if the shot rows were loaded differently to produce a variable burden blasting pattern.

  20. Membranes replace irradiated blast cells as growth requirement for leukemic blast progenitors in suspension culture

    International Nuclear Information System (INIS)

    Nara, N.; McCulloch, E.A.

    1985-01-01

    The blast cells of acute myeloblastic leukemia (AML) may be considered as a renewal population, maintained by blast stem cells capable of both self-renewal and the generation of progeny with reduced or absent proliferative potential. This growth requires that two conditions be met: first, the cultures must contain growth factors in media conditioned either by phytohemagglutinin (PHA)-stimulated mononuclear leukocytes (PHA-LCM), or by cells of the continuous bladder carcinoma line HTB9 (HTB9-CM). Second, the cell density must be maintained at 10(6) blasts/ml; this may be achieved by adding irradiated cells to smaller numbers of intact blasts. The authors are concerned with the mechanism of the feeding function. They present evidence that (a) cell-cell contact is required. (b) Blasts are heterogeneous in respect to their capacity to support growth. (c) Fractions containing membranes from blast cells will substitute for intact cells in promoting the generation of new blast progenitors in culture. (d) This membrane function may be specific for AML blasts, since membranes from blasts of lymphoblastic leukemia or normal marrow cells were inactive

  1. Automatic electromagnetic valve for previous vacuum

    International Nuclear Information System (INIS)

    Granados, C. E.; Martin, F.

    1959-01-01

    A valve which permits the maintenance of an installation vacuum when electric current fails is described. It also lets the air in the previous vacuum bomb to prevent the oil ascending in the vacuum tubes. (Author)

  2. Uses of the vacuum

    International Nuclear Information System (INIS)

    Rohrlich, D.M.

    1986-01-01

    Three problems in quantum field theory are analyzed. Each presents the vacuum in a different role. The connections among these significant roles are discussed in Chapter I. Chapter II contains a calculation of the zero-point energy in the Kaluza-Klein model. The zero-point fluctuations induce a potential which makes the compact dimensional contract. The effective potential is seen to be the four-dimensional version of the Casimir effect. Chapter III contains a Monte Carlo study of asymptotic freedom scales in lattice QCD. Two versions of SU(2) gauge theory, having different representations of the gauge group, are compared. A new method is used to calculate the ratio of scale parameters of the two theories. The method directly uses the weak-coupling behavior of the theories. The Monte-Carlo results are compared with perturbative calculations on the lattice, one of which is presented. They are in good agreement. Chapter IV applies the hypothesis of dimensional reduction to five-dimensional SU(2) and four-dimensional SO(3) lattice gauge theories. New analytic results for the strong- and weak-coupling limits are derived. Monte Carlo calculations show dimensional reduction in the strong coupling phases of both theories. At the phase transition, the two theories show a similar loss of dimensional reduction. An external source of random flux does not induce dimensional reduction where it is not already present

  3. Changing MFTF vacuum environment

    International Nuclear Information System (INIS)

    Margolies, D.; Valby, L.

    1982-01-01

    The Mirror Fusion Test Facility (MFTF) vaccum vessel will be about 60m long and 10m in diameter at the widest point. The allowable operating densities range from 2 x 10 9 to 5 x 10 10 particles per cc. The maximum leak rate of 10 -6 tl/sec is dominated during operation by the deliberately injected cold gas of 250 tl/sec. This gas is pumped by over 1000 square meters of cryopanels, external sorbtion pumps and getters. The design and requirements have changed radically over the past several years, and they are still not in final form. The vacuum system design has also changed, but more slowly and less radically. This paper discusses the engineering effort necessary to meet these stringent and changing requirements. Much of the analysis of the internal systems has been carried out using a 3-D Monte Carlo computer code, which can estimate time dependent operational pressures. This code and its use will also be described

  4. Vacuum type D initial data

    Science.gov (United States)

    García-Parrado Gómez-Lobo, Alfonso

    2016-09-01

    A vacuum type D initial data set is a vacuum initial data set of the Einstein field equations whose data development contains a region where the space–time is of Petrov type D. In this paper we give a systematic characterisation of a vacuum type D initial data set. By systematic we mean that the only quantities involved are those appearing in the vacuum constraints, namely the first fundamental form (Riemannian metric) and the second fundamental form. Our characterisation is a set of conditions consisting of the vacuum constraints and some additional differential equations for the first and second fundamental forms These conditions can be regarded as a system of partial differential equations on a Riemannian manifold and the solutions of the system contain all possible regular vacuum type D initial data sets. As an application we particularise our conditions for the case of vacuum data whose data development is a subset of the Kerr solution. This has applications in the formulation of the nonlinear stability problem of the Kerr black hole.

  5. Vacuum vessel for thermonuclear device

    International Nuclear Information System (INIS)

    Hagiwara, Koji; Imura, Yasuya.

    1979-01-01

    Purpose: To provide constituted method for easily performing baking of vacuum vessel, using short-circuiting segments. Constitution: At the time of baking, one turn circuit is formed by the vacuum vessel and short-circuiting segments, and current transformer converting the one turn circuit into a secondary circuit by the primary coil and iron core is formed, and the vacuum vessel is Joule heated by an induction current from the primary coil. After completion of baking, the short-circuiting segments are removed. (Kamimura, M.)

  6. Vacuum system for HIMAC synchrotrons

    International Nuclear Information System (INIS)

    Kanazawa, M.; Sudou, M.; Sato, K.

    1994-01-01

    HIMAC synchrotrons are now under construction, which require vacuum chambers of large aperture and high vacuum of about 10 -9 torr. Wide thin wall vacuum chamber of 0.3 mm thickness reinforced with ribs has been developed as the chamber at dipole magnet. We have just now started to evacuate the lower ring. The obtained average value was about 5x10 -8 torr with turbo-molecular and sputter ion pumps, and 1.1x10 -9 torr after baking. (author)

  7. The localized quantum vacuum field

    International Nuclear Information System (INIS)

    Dragoman, D

    2008-01-01

    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

  8. The localized quantum vacuum field

    Energy Technology Data Exchange (ETDEWEB)

    Dragoman, D [Physics Department, University of Bucharest, PO Box MG-11, 077125 Bucharest (Romania)], E-mail: danieladragoman@yahoo.com

    2008-03-15

    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.

  9. Resistor cooling in a vacuum

    International Nuclear Information System (INIS)

    Crittenden, R.; Krider, J.

    1987-01-01

    This note describes thermal measurements which were done on a resistor operating both in air at one atmosphere pressure and in a vacuum of a few milliTorr. The motivation for this measurement was our interest in operating a BGO crystal-photomultiplier tube-base assembly in a vacuum, as a synchrotron radiation detector to tag electrons in the MT beam. We wished to determine what fraction of the total resistor power was dissipated by convection in air, in order to know whether there would be excessive heating of the detector assembly in a vacuum. 3 figs

  10. Experimental tests of vacuum energy

    CERN Multimedia

    CERN. Geneva

    2015-01-01

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

  11. Blast Mitigation Using Water - A Status Report

    National Research Council Canada - National Science Library

    Kailasanath, K

    2002-01-01

    ..., and aggressive research and development', this report reviews the current knowledge base on blast mitigation using water and identifies the key issues that need to be resolved in order to develop...

  12. International blast furnace hearth and raceway symposium

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    Papers presented discussed some of the physical and chemical processes occuring in the raceway and hearths of blast furnaces. The injection of coal or fuel slurries to replace some of the coke was also covered. Fourteen papers are abstracted separately.

  13. Basic Local Alignment Search Tool (BLAST)

    Data.gov (United States)

    U.S. Department of Health & Human Services — BLAST finds regions of similarity between biological sequences. The program compares nucleotide or protein sequences to sequence databases and calculates the...

  14. A Software Framework for Blast Event Simulation

    National Research Council Canada - National Science Library

    Swensen, D. A; Denison, M. K; Guilkey, James; Harman, Todd; Goetz, Richard

    2006-01-01

    .... The BCF will provide a virtual test-bed where disparate computational models can seamlessly interact with one another to provide a unified modeling solution for blast-vehicle-occupant scenarios...

  15. Bomb blast imaging: bringing order to chaos.

    Science.gov (United States)

    Dick, E A; Ballard, M; Alwan-Walker, H; Kashef, E; Batrick, N; Hettiaratchy, S; Moran, C G

    2018-06-01

    Blast injuries are complex, severe, and outside of our everyday clinical practice, but every radiologist needs to understand them. By their nature, bomb blasts are unpredictable and affect multiple victims, yet require an immediate, coordinated, and whole-hearted response from all members of the clinical team, including all radiology staff. This article will help you gain the requisite expertise in blast imaging including recognising primary, secondary, and tertiary blast injuries. It will also help you understand the fundamental role that imaging plays during mass casualty attacks and how to avoid radiology becoming a bottleneck to the forward flow of severely injured patients as they are triaged and treated. Copyright © 2018. Published by Elsevier Ltd.

  16. On firework blasts and qualitative parameter dependency.

    Science.gov (United States)

    Zohdi, T I

    2016-01-01

    In this paper, a mathematical model is developed to qualitatively simulate the progressive time-evolution of a blast from a simple firework. Estimates are made for the blast radius that one can expect for a given amount of detonation energy and pyrotechnic display material. The model balances the released energy from the initial blast pulse with the subsequent kinetic energy and then computes the trajectory of the material under the influence of the drag from the surrounding air, gravity and possible buoyancy. Under certain simplifying assumptions, the model can be solved for analytically. The solution serves as a guide to identifying key parameters that control the evolving blast envelope. Three-dimensional examples are given.

  17. Blast effects physical properties of shock waves

    CERN Document Server

    2018-01-01

    This book compiles a variety of experimental data on blast waves. The book begins with an introductory chapter and proceeds to the topic of blast wave phenomenology, with a discussion Rankine-Hugoniot equations and the Friedlander equation, used to describe the pressure-time history of a blast wave. Additional topics include arrival time measurement, the initiation of detonation by exploding wires, a discussion of TNT equivalency, and small scale experiments. Gaseous and high explosive detonations are covered as well. The topics and experiments covered were chosen based on the comparison of used scale sizes, from small to large. Each characteristic parameter of blast waves is analyzed and expressed versus scaled distance in terms of energy and mass. Finally, the appendix compiles a number of polynomial laws that will prove indispensable for engineers and researchers.

  18. Blasting at a Superfund chemical waste site

    International Nuclear Information System (INIS)

    Burns, D.R.

    1991-01-01

    During the summer of 1989, Maine Drilling and Blasting of Gardiner, Maine was contracted by Cayer Corporation of Harvard, Massachusetts to drill and blast an interceptor trench at the Nyanza Chemical Superfund Site in Ashland, Massachusetts. The interceptor trench was to be 1,365 feet long and to be blasted out of granite. The trench was to be 12 feet wide at the bottom with 1/1 slopes, the deepest cut being 30 feet deep. A French drain 12 feet wide by 15 to 35 feet deep was blasted below the main trench on a 2% slope from its center to each end. A French drain is an excavation where the rock is blasted but not dug. The trench would be used as a perimeter road with any ground water flow going through the French drain flowing to both ends of the trench. Being a Superfund project turned a simple blasting project into a regulatory nightmare. The US Environmental Protection Agency performed all the chemical related functions on site. The US Army Corps of Engineers was overseeing all related excavation and construction on site, as was the Massachusetts Department of Environmental Quality Engineering, the local Hazardous Wastes Council, and the local Fire Department. All parties had some input with the blasting and all issues had to be addressed. The paper outlines the project, how it was designed and completed. Also included is an outline of the blast plan to be submitted for approval, an outline of the Safety/Hazardous Waste training and a description of all the problems which arose during the project by various regulatory agencies

  19. NCSX Vacuum Vessel Fabrication

    International Nuclear Information System (INIS)

    Viola ME; Brown T; Heitzenroeder P; Malinowski F; Reiersen W; Sutton L; Goranson P; Nelson B; Cole M; Manuel M; McCorkle D.

    2005-01-01

    The National Compact Stellarator Experiment (NCSX) is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in conjunction with the Oak Ridge National Laboratory (ORNL). The goal of this experiment is to develop a device which has the steady state properties of a traditional stellarator along with the high performance characteristics of a tokamak. A key element of this device is its highly shaped Inconel 625 vacuum vessel. This paper describes the manufacturing of the vessel. The vessel is being fabricated by Major Tool and Machine, Inc. (MTM) in three identical 120 o vessel segments, corresponding to the three NCSX field periods, in order to accommodate assembly of the device. The port extensions are welded on, leak checked, cut off within 1-inch of the vessel surface at MTM and then reattached at PPPL, to accommodate assembly of the close-fitting modular coils that surround the vessel. The 120 o vessel segments are formed by welding two 60 o segments together. Each 60 o segment is fabricated by welding ten press-formed panels together over a collapsible welding fixture which is needed to precisely position the panels. The vessel is joined at assembly by welding via custom machined 8-inch (20.3 cm) wide spacer ''spool pieces''. The vessel must have a total leak rate less than 5 X 10 -6 t-l/s, magnetic permeability less than 1.02(micro), and its contours must be within 0.188-inch (4.76 mm). It is scheduled for completion in January 2006

  20. Blasting in hot zone - a case study

    Energy Technology Data Exchange (ETDEWEB)

    Nabiullah, B.M.P.; Pingua, J.; Dhar, B.B. [Central Mining Research Institute, Dhanbad (India)

    1997-12-31

    A significant quantity of coking coal reserves in the country are under fire particularly in Jharia coalfield. To control the fire and prevent loss of coal, an opencast mining method is adopted. The main problem with these opencast mines is drilling in hot strata and selection of suitable explosives and blasting in the fire zone. Trial blasts were conducted at two open cast mines. The problem was tackled by quenching the hot blast holes with water. Temperature of blast holes were recorded soon after drilling, after quenching with water and just before charging with explosives. The rise in temperature of charged explosives with time was also recorded until blasting. The thermal behaviour of commercially available explosives (including slurry, emulsion, ANFO and detonating cord) was investigated in laboratory and field simulated conditions. Emulsion, slurry compositions and detonating cord were found safe to use in hot holes up to 120{degree}C for duration of two hours. This paper describes the blasting practices adopted in the fire zones. 4 refs., 6 figs., 8 tabs.

  1. Ultra Safe And Secure Blasting System

    Energy Technology Data Exchange (ETDEWEB)

    Hart, M M

    2009-07-27

    The Ultra is a blasting system that is designed for special applications where the risk and consequences of unauthorized demolition or blasting are so great that the use of an extraordinarily safe and secure blasting system is justified. Such a blasting system would be connected and logically welded together through digital code-linking as part of the blasting system set-up and initialization process. The Ultra's security is so robust that it will defeat the people who designed and built the components in any attempt at unauthorized detonation. Anyone attempting to gain unauthorized control of the system by substituting components or tapping into communications lines will be thwarted in their inability to provide encrypted authentication. Authentication occurs through the use of codes that are generated by the system during initialization code-linking and the codes remain unknown to anyone, including the authorized operator. Once code-linked, a closed system has been created. The system requires all components connected as they were during initialization as well as a unique code entered by the operator for function and blasting.

  2. The second generation of electronic blasting systems

    Energy Technology Data Exchange (ETDEWEB)

    Hammelmann, F.; Petzold, J. [Dynamit Nobel GmbH (Germany)

    2001-07-01

    8 years after the market introduction of the first commercial electronic detonator - DYNATRONIC - the paper describes a new area of electronic blasting systems Made in Germany: i-kon. The results of a joint development between Dynamit Nobel and Orica is a unique universal electronic detonator, which is as simple to use as a standard non-electric detonator. The delay time or delay interval is not factory preprogrammed and the system is not based on a numbered system like conventional detonators. The miner or Blaster decides on site which delay timing he likes to use and is programming the whole blast on site. The new i-kon system allows delay times between 0 and 8000 ms by increments of 1 ms. With the control equipment it is possible to blast up to 1600 detonators in a single blast. The paper describes the construction and functionality of this new electronic blasting system - manufactured and developed by Precision Blasting Systems, a joint venture between Orica and Dynamic Nobel. (orig.)

  3. Particle creation during vacuum decay

    International Nuclear Information System (INIS)

    Rubakov, V.A.

    1984-01-01

    The hamiltonian approach is developed with regard to the problem of particle creation during the tunneling process, leading to the decay of the false vacuum in quantum field theory. It is shown that, to the lowest order in (h/2π), the particle creation is described by the euclidean Schroedinger equation in an external field of a bounce. A technique for solving this equation is developed in an analogy to the Bogoliubov transformation technique, in the theory of particle creation in the presence of classical background fields. The technique is illustrated by two examples, namely, the particle creation during homogeneous vacuum decay and during the tunneling process leading to the materialization of the thin-wall bubble of a new vacuum in the metastable one. The curious phenomenon of intensive particle annihilation during vacuum decay is discussed and explicitly illustrated within the former example. The non-unitary extension of the Bogoliubov u, v transformations is described in the appendix. (orig.)

  4. Vacuum in intensive gauge fields

    International Nuclear Information System (INIS)

    Matinian, S.G.

    1977-12-01

    The behaviour of vacuum in a covariantly constant Yang-Mills field is considered. The expressions for the effective Lagrangian in an intensive field representing the asymptotic freedom of the theory are found

  5. Effect of blasting on output increase of bucket wheel excavators

    Energy Technology Data Exchange (ETDEWEB)

    Musil, P.

    1987-12-01

    In brown coal surface mines, consolidated sediments become a problem as mining operations advance into greater depth below the original terrain. Owing to higher digging resistance, the output of bucket wheel excavators drops. This problem may be solved by blasting technology and using drilling machines with higher digging force. This paper describes the blasting operations at the Nastup Mines in Tusmice, Czechoslovakia. About 60% of blasting explosives used is a simple mixture of ammonium nitrate and fuel (ANFO), the rest falls on classic blasting gelatines and blasting explosives plasticized by slurry. It is found that blasting improves output by 30% while electric energy consumption is reduced.

  6. Vacuum production; Produccion de vacio

    Energy Technology Data Exchange (ETDEWEB)

    Segovia, J. L. de

    2010-07-01

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

  7. Development of vacuum brazing furnace

    International Nuclear Information System (INIS)

    Singh, Rajvir; Yedle, Kamlesh; Jain, A.K.

    2005-01-01

    In joining of components where welding process is not possible brazing processes are employed. Value added components, high quality RF systems, UHV components of high energy accelerators, carbide tools etc. are produced using different types of brazing methods. Furnace brazing under vacuum atmosphere is the most popular and well accepted method for production of the above mentioned components and systems. For carrying out vacuum brazing successfully it is essential to have a vacuum brazing furnace with latest features of modern vacuum brazing technology. A vacuum brazing furnace has been developed and installed for carrying out brazing of components of copper, stainless steel and components made of dissimilar metals/materials. The above furnace has been designed to accommodate jobs of 700mm diameter x 2000mm long sizes with job weight of 500kgs up to a maximum temperature of 1250 degC at a vacuum of 5 x 10 -5 Torr. Oil diffusion pumping system with a combination of rotary and mechanical booster pump have been employed for obtaining vacuum. Molybdenum heating elements, radiation shield of molybdenum and Stainless Steel Grade 304 have been used. The above furnace is computer controlled with manual over ride facility. PLC and Pentium PC are integrated together to maneuver steps of operation and safety interlocks of the system. Closed loop water supply provides cooling to the system. The installation of the above system is in final stage of completion and it will be ready for use in next few months time. This paper presents insights of design and fabrication of a modern vacuum brazing furnace and its sub-system. (author)

  8. Vacuum energy from noncommutative models

    Science.gov (United States)

    Mignemi, S.; Samsarov, A.

    2018-04-01

    The vacuum energy is computed for a scalar field in a noncommutative background in several models of noncommutative geometry. One may expect that the noncommutativity introduces a natural cutoff on the ultraviolet divergences of field theory. Our calculations show however that this depends on the particular model considered: in some cases the divergences are suppressed and the vacuum energy is only logarithmically divergent, in other cases they are stronger than in the commutative theory.

  9. ITER diagnostic system: Vacuum interface

    International Nuclear Information System (INIS)

    Patel, K.M.; Udintsev, V.S.; Hughes, S.; Walker, C.I.; Andrew, P.; Barnsley, R.; Bertalot, L.; Drevon, J.M.; Encheva, A.; Kashchuk, Y.; Maquet, Ph.; Pearce, R.; Taylor, N.; Vayakis, G.; Walsh, M.J.

    2013-01-01

    Diagnostics play an essential role for the successful operation of the ITER tokamak. They provide the means to observe control and to measure plasma during the operation of ITER tokamak. The components of the diagnostic system in the ITER tokamak will be installed in the vacuum vessel, in the cryostat, in the upper, equatorial and divertor ports, in the divertor cassettes and racks, as well as in various buildings. Diagnostic components that are placed in a high radiation environment are expected to operate for the life of ITER. There are approx. 45 diagnostic systems located on ITER. Some diagnostics incorporate direct or independently pumped extensions to maintain their necessary vacuum conditions. They require a base pressure less than 10 −7 Pa, irrespective of plasma operation, and a leak rate of less than 10 −10 Pa m 3 s −1 . In all the cases it is essential to maintain the ITER closed fuel cycle. These directly coupled diagnostic systems are an integral part of the ITER vacuum containment and are therefore subject to the same design requirements for tritium and active gas confinement, for all normal and accidental conditions. All the diagnostics, whether or not pumped, incorporate penetration of the vacuum boundary (i.e. window assembly, vacuum feedthrough etc.) and demountable joints. Monitored guard volumes are provided for all elements of the vacuum boundary that are judged to be vulnerable by virtue of their construction, material, load specification etc. Standard arrangements are made for their construction and for the monitoring, evacuating and leak testing of these volumes. Diagnostic systems are incorporated at more than 20 ports on ITER. This paper will describe typical and particular arrangements of pumped diagnostic and monitored guard volume. The status of the diagnostic vacuum systems, which are at the start of their detailed design, will be outlined and the specific features of the vacuum systems in ports and extensions will be described

  10. ITER diagnostic system: Vacuum interface

    Energy Technology Data Exchange (ETDEWEB)

    Patel, K.M., E-mail: Kaushal.Patel@iter.org [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-Lez-Durance (France); Udintsev, V.S.; Hughes, S.; Walker, C.I.; Andrew, P.; Barnsley, R.; Bertalot, L. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-Lez-Durance (France); Drevon, J.M. [Bertin Technologies, BP 22, 13762 Aix-en Provence cedex 3 (France); Encheva, A. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-Lez-Durance (France); Kashchuk, Y. [Institution “PROJECT CENTER ITER”, 1, Akademika Kurchatova pl., Moscow (Russian Federation); Maquet, Ph. [Bertin Technologies, BP 22, 13762 Aix-en Provence cedex 3 (France); Pearce, R.; Taylor, N.; Vayakis, G.; Walsh, M.J. [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul-Lez-Durance (France)

    2013-10-15

    Diagnostics play an essential role for the successful operation of the ITER tokamak. They provide the means to observe control and to measure plasma during the operation of ITER tokamak. The components of the diagnostic system in the ITER tokamak will be installed in the vacuum vessel, in the cryostat, in the upper, equatorial and divertor ports, in the divertor cassettes and racks, as well as in various buildings. Diagnostic components that are placed in a high radiation environment are expected to operate for the life of ITER. There are approx. 45 diagnostic systems located on ITER. Some diagnostics incorporate direct or independently pumped extensions to maintain their necessary vacuum conditions. They require a base pressure less than 10{sup −7} Pa, irrespective of plasma operation, and a leak rate of less than 10{sup −10} Pa m{sup 3} s{sup −1}. In all the cases it is essential to maintain the ITER closed fuel cycle. These directly coupled diagnostic systems are an integral part of the ITER vacuum containment and are therefore subject to the same design requirements for tritium and active gas confinement, for all normal and accidental conditions. All the diagnostics, whether or not pumped, incorporate penetration of the vacuum boundary (i.e. window assembly, vacuum feedthrough etc.) and demountable joints. Monitored guard volumes are provided for all elements of the vacuum boundary that are judged to be vulnerable by virtue of their construction, material, load specification etc. Standard arrangements are made for their construction and for the monitoring, evacuating and leak testing of these volumes. Diagnostic systems are incorporated at more than 20 ports on ITER. This paper will describe typical and particular arrangements of pumped diagnostic and monitored guard volume. The status of the diagnostic vacuum systems, which are at the start of their detailed design, will be outlined and the specific features of the vacuum systems in ports and extensions

  11. Proceedings of the twenty-seventh annual conference on explosives and blasting techniques

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Various aspects of explosives and blasting techniques are covered. Those of particular interest to the coal industry buffer blasting versus cast blasting, post-blast cast profile shape prediction, fragmentation model to estimate ROM size distribution of soft rocks, blasting accidents, blast vibrations, ANFO explosives and carbon monoxide poisoning.

  12. DYNAMIC TIME HISTORY ANALYSIS OF BLAST RESISTANT DOOR USING BLAST LOAD MODELED AS IMPACT LOAD

    Directory of Open Access Journals (Sweden)

    Y. A. Pranata

    2012-06-01

    Full Text Available A blast resistant single door was designed to withstand a 0.91 bar blast pressure and 44 ms blast duration. The analysis was done using Dynamic Time History Analysis using Blast Load modeled as Impact Load for given duration. The material properties used have been modified to accommodate dynamic effects. The analysis was done using dynamic finite element method (fem for time of the blast duration, and the maximum/minimum internal forces and displacement were taken from the time history output, in order to know the behavior under blast load and estimate the safety margin of the door. Results obtained from this research indicated that the maximum z-displacement is 1.709 mm, while in the term of serviceability, the permitted is 25 mm. The maximum reaction force is 73,960 N, while the maximum anchor capacity is 82,069 N. On blast condition, the maximum frame stress is 71.71 MPa, the maximum hinge shear stress is 45.28 MPa. While on rebound condition, the maximum frame stress is 172.11 MPa, the maximum hinge shear stress is 29.46 MPa. The maximum door edge rotation is 0.44 degree, which is not exceed the permitted boundary (1.2 degree. Keywords: Dynamic time history, blast resistant door, single door, finite element method.

  13. Raydet non-electric blast initiation system for efficient and environment-friendly surface blasts

    Energy Technology Data Exchange (ETDEWEB)

    Sarathy, M.O. [IDL Chemicals Ltd., Hyderabad (India). Technical Services Cell

    1995-08-01

    This paper discusses the advantages of using the Raydet shock tube based blast initiation system and reviews research work carried out on release of explosive energy in the drillhole, effect of stemming retention (stemming effectiveness) and advantages of `true bottom hole initiation` of drillholes in surface blasting. Some case studies are presented. 6 refs., 5 figs., 1 tab.

  14. Technical specification for vacuum systems

    International Nuclear Information System (INIS)

    Khaw, J.

    1987-01-01

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

  15. Vacuum vessel for thermonuclear device

    International Nuclear Information System (INIS)

    Kikuchi, Mitsuru; Kurita, Gen-ichi; Onozuka, Masaki; Suzuki, Masaru.

    1997-01-01

    Heat of inner walls of a vacuum vessel that receive radiation heat from plasmas by way of first walls is removed by a cooling medium flowing in channels for cooling the inner walls. Nuclear heat generation of constitutional materials of the vacuum vessel caused by fast neutrons and γ rays is removed by a cooling medium flowing in cooling channels disposed in the vacuum vessel. Since the heat from plasmas and the nuclear heat generation are removed separately, the amount of the cooling medium flowing in the channels for cooling inner walls is increased for cooling a great amount of heat from plasmas while the amount of the cooling medium flowing in the channels for cooling the inside of the vacuum vessel is reduced for cooling the small amount of nuclear heat generation. Since the amount of the cooling medium can thus be optimized, the capacity of the facilities for circulating the cooling medium can be reduced. In addition, since the channels for cooling the inner walls and the channels of cooling medium formed in the vacuum vessel are disposed to the inner walls of the vacuum vessel on the side opposite to plasmas, integrity of the channels relative to leakage of the cooling medium can be ensured. (N.H.)

  16. Vacuum vessel for thermonuclear device

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Mitsuru; Kurita, Gen-ichi [Japan Atomic Energy Research Inst., Tokyo (Japan); Onozuka, Masaki; Suzuki, Masaru

    1997-07-31

    Heat of inner walls of a vacuum vessel that receive radiation heat from plasmas by way of first walls is removed by a cooling medium flowing in channels for cooling the inner walls. Nuclear heat generation of constitutional materials of the vacuum vessel caused by fast neutrons and {gamma} rays is removed by a cooling medium flowing in cooling channels disposed in the vacuum vessel. Since the heat from plasmas and the nuclear heat generation are removed separately, the amount of the cooling medium flowing in the channels for cooling inner walls is increased for cooling a great amount of heat from plasmas while the amount of the cooling medium flowing in the channels for cooling the inside of the vacuum vessel is reduced for cooling the small amount of nuclear heat generation. Since the amount of the cooling medium can thus be optimized, the capacity of the facilities for circulating the cooling medium can be reduced. In addition, since the channels for cooling the inner walls and the channels of cooling medium formed in the vacuum vessel are disposed to the inner walls of the vacuum vessel on the side opposite to plasmas, integrity of the channels relative to leakage of the cooling medium can be ensured. (N.H.)

  17. Comparison of Some Blast Vibration Predictors for Blasting in Underground Drifts and Some Observations

    Science.gov (United States)

    Bhagwat, Vaibhab Pramod; Dey, Kaushik

    2016-04-01

    Drilling and blasting are the most economical excavation techniques in underground drifts driven through hard rock formation. Burn cut is the most popular drill pattern, used in this case, to achieve longer advance per blast round. The ground vibration generated due to the propagation of blast waves on the detonation of explosive during blasting is the principal cause for structural and rock damage. Thus, ground vibration is a point of concern for the blasting engineers. The ground vibration from a blast is measured using a seismograph placed at the blast monitoring station. The measured vibrations, in terms of peak particle velocity, are related to the maximum charge detonated at one instant and the distance of seismograph from the blast point. The ground vibrations from a number of blast rounds of varying charge/delay and distances are monitored. A number of scaling factors of these dependencies (viz. Distance and maximum charge/delay) have been proposed by different researchers, namely, square root, cube root, CMRI, Langefors and Kihlstrom, Ghosh-Daemon, Indian standard etc. Scaling factors of desired type are computed for all the measured blast rounds. Regression analysis is carried out between the scaling factors and peak particle velocities to establish the coefficients of the vibration predictor equation. Then, the developed predictor equation is used for designing the blast henceforth. Director General of Mine Safety, India, specified that ground vibrations from eight to ten blast rounds of varying charge/delay and distances should be monitored to develop a predictor equation; however, there is no guideline about the type of scaling factor to be used. Further to this, from the statistical point of view, a regression analysis on a small sample population cannot be accepted without the testing of hypothesis. To show the importance of the above, in this paper, seven scaling factors are considered for blast data set of a hard-rock underground drift using burn

  18. BLAST-EXPLORER helps you building datasets for phylogenetic analysis

    Directory of Open Access Journals (Sweden)

    Claverie Jean-Michel

    2010-01-01

    Full Text Available Abstract Background The right sampling of homologous sequences for phylogenetic or molecular evolution analyses is a crucial step, the quality of which can have a significant impact on the final interpretation of the study. There is no single way for constructing datasets suitable for phylogenetic analysis, because this task intimately depends on the scientific question we want to address, Moreover, database mining softwares such as BLAST which are routinely used for searching homologous sequences are not specifically optimized for this task. Results To fill this gap, we designed BLAST-Explorer, an original and friendly web-based application that combines a BLAST search with a suite of tools that allows interactive, phylogenetic-oriented exploration of the BLAST results and flexible selection of homologous sequences among the BLAST hits. Once the selection of the BLAST hits is done using BLAST-Explorer, the corresponding sequence can be imported locally for external analysis or passed to the phylogenetic tree reconstruction pipelines available on the Phylogeny.fr platform. Conclusions BLAST-Explorer provides a simple, intuitive and interactive graphical representation of the BLAST results and allows selection and retrieving of the BLAST hit sequences based a wide range of criterions. Although BLAST-Explorer primarily aims at helping the construction of sequence datasets for further phylogenetic study, it can also be used as a standard BLAST server with enriched output. BLAST-Explorer is available at http://www.phylogeny.fr

  19. Research on Effects of Blast Casting Vibration and Vibration Absorption of Presplitting Blasting in Open Cast Mine

    Directory of Open Access Journals (Sweden)

    Li Ma

    2016-01-01

    Full Text Available The impact energy produced by blast casting is able to break and cast rocks, yet the strong vibration effects caused at the same time would threaten the safety of mines. Based on the theory of Janbu’s Limit Equilibrium Method (LEM, pseudo-static method has been incorporated to analyze the influence of dynamic loads of blasting on slope stability. The horizontal loads produced by blast vibrations cause an increase in sliding forces, and this leads to a lower slope stability coefficient. When the tensile stresses of the two adjacent blast holes are greater than the tensile strength of rock mass, the radical oriented cracks are formed, which is the precondition for the formation of presplit face. Thus, the formula for calculating the blast hole spacing of presplit blasting can be obtained. Based on the analysis of the principles of vibration tester and vibration pick-up in detecting blast vibrations, a detection scheme of blast vibration is worked out by taking the blast area with precrack rear and non-precrack side of the detection object. The detection and research results of blast vibration show that presplit blasting can reduce the attenuation coefficient of stress wave by half, and the vibration absorption ratio could reach 50.2%; the impact of dynamic loads on the end-wall slope stability coefficient is 1.98%, which proves that presplit blasting plays an important role in shock absorption of blast casting.

  20. Vacuum vessel for thermonuclear device

    International Nuclear Information System (INIS)

    Kikuchi, Mitsuru; Nagashima, Keisuke; Suzuki, Masaru; Onozuka, Masaki.

    1997-01-01

    A vacuum vessel main body and structural members at the inside and the outside of the vacuum vessel main body are constituted by structural materials activated by irradiation of neutrons from plasmas such as stainless steels. Shielding members comprising tungsten or molybdenum are disposed on the surface of the vacuum vessel main body and the structural members of the inside and the outside of the main body. The shielding members have a function also as first walls or a seat member for the first walls. Armor tiles may be disposed to the shielding members. The shielding members and the armor tiles are secured to a securing seat member disposed, for example, to an inner plate of the vacuum vessel main body by bolts. Since the shielding members are disposed, it is not necessary to constitute the vacuum vessel main body and the structural members at the inside and the outside thereof by using a low activation material which is less activated, such as a titanium alloy. (I.N.)

  1. Vacuum vessel for thermonuclear device

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Mitsuru; Nagashima, Keisuke [Japan Atomic Energy Research Inst., Tokyo (Japan); Suzuki, Masaru; Onozuka, Masaki

    1997-07-11

    A vacuum vessel main body and structural members at the inside and the outside of the vacuum vessel main body are constituted by structural materials activated by irradiation of neutrons from plasmas such as stainless steels. Shielding members comprising tungsten or molybdenum are disposed on the surface of the vacuum vessel main body and the structural members of the inside and the outside of the main body. The shielding members have a function also as first walls or a seat member for the first walls. Armor tiles may be disposed to the shielding members. The shielding members and the armor tiles are secured to a securing seat member disposed, for example, to an inner plate of the vacuum vessel main body by bolts. Since the shielding members are disposed, it is not necessary to constitute the vacuum vessel main body and the structural members at the inside and the outside thereof by using a low activation material which is less activated, such as a titanium alloy. (I.N.)

  2. Effectiveness of eye armor during blast loading.

    Science.gov (United States)

    Bailoor, Shantanu; Bhardwaj, Rajneesh; Nguyen, Thao D

    2015-11-01

    Ocular trauma is one of the most common types of combat injuries resulting from the interaction of military personnel with improvised explosive devices. Ocular blast injury mechanisms are complex, and trauma may occur through various injury mechanisms. However, primary blast injuries (PBI) are an important cause of ocular trauma that may go unnoticed and result in significant damage to internal ocular tissues and visual impairment. Further, the effectiveness of commonly employed eye armor, designed for ballistic and laser protection, in lessening the severity of adverse blast overpressures (BOP) is unknown. In this paper, we employed a three-dimensional (3D) fluid-structure interaction computational model for assessing effectiveness of the eye armor during blast loading on human eyes and validated results against free field blast measurements by Bentz and Grimm (2013). Numerical simulations show that the blast waves focused on the ocular region because of reflections from surrounding facial features and resulted in considerable increase in BOP. We evaluated the effectiveness of spectacles and goggles in mitigating the pressure loading using the computational model. Our results corroborate experimental measurements showing that the goggles were more effective than spectacles in mitigating BOP loading on the eye. Numerical results confirmed that the goggles significantly reduced blast wave penetration in the space between the armor and the eyes and provided larger clearance space for blast wave expansion after penetration than the spectacles. The spectacles as well as the goggles were more effective in reducing reflected BOP at higher charge mass because of the larger decrease in dynamic pressures after the impact. The goggles provided greater benefit of reducing the peak pressure than the spectacles for lower charge mass. However, the goggles resulted in moderate, sustained elevated pressure loading on the eye, that became 50-100% larger than the pressure loading

  3. Blast densification trials for oilsands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Port, A. [Klohn Crippen Berger Ltd., Vancouver, BC (Canada); Martens, S. [Klohn Crippen Berger Ltd., Calgary, AB (Canada); Eaton, T. [Shell Canada Ltd., Calgary, AB (Canada)

    2010-07-01

    The Shell Canada Muskeg River Mine External Tailings Facility (ETF) is an upstream constructed tailings facility located near Fort McMurray, Alberta. Raises have incrementally stepped out over the beach since construction of the starter dam and deposition within standing water has left some parts of the beach in a loose state. In order to assess the effectiveness of blast densification, a blast densification trial program that was conducted in 2006 at the ETF. The primary purpose of the test program was to determine the effectiveness of blast densification in tailings containing layers and zones of bitumen. The paper described the site characterization and explosive compaction trial program, with particular reference to test layout; drilling methodology; and blasting and timing sequence. The paper also described the instrumentation, including the seismographs; high pressure electric piezometers; low pressure electric piezometers; vibrating wire piezometers; inclinometers; settlement gauges; and surveys. Trial observations and post-trial observations were also presented. It was concluded that controlled blasting techniques could be used to safely induce liquefaction in localized areas within the tailings deposit, with a resulting increase in the tailings density. 5 refs., 1 tab., 14 figs.

  4. Modelling human eye under blast loading.

    Science.gov (United States)

    Esposito, L; Clemente, C; Bonora, N; Rossi, T

    2015-01-01

    Primary blast injury (PBI) is the general term that refers to injuries resulting from the mere interaction of a blast wave with the body. Although few instances of primary ocular blast injury, without a concomitant secondary blast injury from debris, are documented, some experimental studies demonstrate its occurrence. In order to investigate PBI to the eye, a finite element model of the human eye using simple constitutive models was developed. The material parameters were calibrated by a multi-objective optimisation performed on available eye impact test data. The behaviour of the human eye and the dynamics of mechanisms occurring under PBI loading conditions were modelled. For the generation of the blast waves, different combinations of explosive (trinitrotoluene) mass charge and distance from the eye were analysed. An interpretation of the resulting pressure, based on the propagation and reflection of the waves inside the eye bulb and orbit, is proposed. The peculiar geometry of the bony orbit (similar to a frustum cone) can induce a resonance cavity effect and generate a pressure standing wave potentially hurtful for eye tissues.

  5. Spalling of concrete walls under blast load

    International Nuclear Information System (INIS)

    Kot, C.A.

    1977-01-01

    A common effect of the detonation of explosives in close proximity of concrete shield walls is the spalling (scabbing) of the back face of the wall. Spalling is caused by the free surface reflection of the shock wave induced in the wall by high pressure air blast and occurs whenever the dynamic tensile rupture strength is exceeded. While a complex process, reasonable analytical spall estimates can be obtained for brittle materials with low tensile strengths, such as concrete, by assuming elastic material behavior and instantaneous spall formation. Specifically, the spall thicknesses and velocities for both normal and oblique incidence of the shock wave on the back face of the wall are calculated. The complex exponential decay wave forms of the air blast are locally approximated by simple power law expressions. Variations of blast wave strength with distance to the wall, charge weight and angle of incidence are taken into consideration. The shock wave decay in the wall is also accounted for by assuming elastic wave propagation. For explosions close-in to the wall, where the reflected blast wave pressures are sufficiently high, multiple spall layers are formed. Successive spall layers are of increasing thickness, at the same time the spall velocities decrease. The spall predictions based on elastic theory are in overall agreement with experimntal results and provide a rapid means of estimating spalling trends of concrete walls subjected to air blast. (Auth.)

  6. 30 CFR 75.1316 - Preparation before blasting.

    Science.gov (United States)

    2010-07-01

    ... two working faces are approaching each other, cutting, drilling and blasting shall be done at only one... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Preparation before blasting. 75.1316 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1316 Preparation...

  7. Carbon nanotubes based vacuum gauge

    Science.gov (United States)

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

    2017-11-01

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

  8. Magnetically enhanced vacuum arc thruster

    International Nuclear Information System (INIS)

    Keidar, Michael; Schein, Jochen; Wilson, Kristi; Gerhan, Andrew; Au, Michael; Tang, Benjamin; Idzkowski, Luke; Krishnan, Mahadevan; Beilis, Isak I

    2005-01-01

    A hydrodynamic model of the vacuum arc thruster and its plume is described. Primarily an effect of the magnetic field on the plume expansion and plasma generation is considered. Two particular examples are investigated, namely the magnetically enhanced co-axial vacuum arc thruster (MVAT) and the vacuum arc thruster with ring electrodes (RVAT). It is found that the magnetic field significantly decreases the plasma plume radial expansion under typical conditions. Predicted plasma density profiles in the plume of the MVAT are compared with experimental profiles, and generally a good agreement is found. In the case of the RVAT the influence of the magnetic field leads to plasma jet deceleration, which explains the non-monotonic dependence of the ion current density, on an axial magnetic field observed experimentally

  9. Magnetically enhanced vacuum arc thruster

    Energy Technology Data Exchange (ETDEWEB)

    Keidar, Michael [University of Michigan, Ann Arbor 48109 MI (United States); Schein, Jochen [Alameda Applied Science Corporation, San Leandro, CA 94577 (United States); Wilson, Kristi [Alameda Applied Science Corporation, San Leandro, CA 94577 (United States); Gerhan, Andrew [Alameda Applied Science Corporation, San Leandro, CA 94577 (United States); Au, Michael [Alameda Applied Science Corporation, San Leandro, CA 94577 (United States); Tang, Benjamin [Alameda Applied Science Corporation, San Leandro, CA 94577 (United States); Idzkowski, Luke [Alameda Applied Science Corporation, San Leandro, CA 94577 (United States); Krishnan, Mahadevan [Alameda Applied Science Corporation, San Leandro, CA 94577 (United States); Beilis, Isak I [Tel Aviv University, Tel Aviv (Israel)

    2005-11-01

    A hydrodynamic model of the vacuum arc thruster and its plume is described. Primarily an effect of the magnetic field on the plume expansion and plasma generation is considered. Two particular examples are investigated, namely the magnetically enhanced co-axial vacuum arc thruster (MVAT) and the vacuum arc thruster with ring electrodes (RVAT). It is found that the magnetic field significantly decreases the plasma plume radial expansion under typical conditions. Predicted plasma density profiles in the plume of the MVAT are compared with experimental profiles, and generally a good agreement is found. In the case of the RVAT the influence of the magnetic field leads to plasma jet deceleration, which explains the non-monotonic dependence of the ion current density, on an axial magnetic field observed experimentally.

  10. Divide and Conquer (DC BLAST: fast and easy BLAST execution within HPC environments

    Directory of Open Access Journals (Sweden)

    Won Cheol Yim

    2017-06-01

    Full Text Available Bioinformatics is currently faced with very large-scale data sets that lead to computational jobs, especially sequence similarity searches, that can take absurdly long times to run. For example, the National Center for Biotechnology Information (NCBI Basic Local Alignment Search Tool (BLAST and BLAST+ suite, which is by far the most widely used tool for rapid similarity searching among nucleic acid or amino acid sequences, is highly central processing unit (CPU intensive. While the BLAST suite of programs perform searches very rapidly, they have the potential to be accelerated. In recent years, distributed computing environments have become more widely accessible and used due to the increasing availability of high-performance computing (HPC systems. Therefore, simple solutions for data parallelization are needed to expedite BLAST and other sequence analysis tools. However, existing software for parallel sequence similarity searches often requires extensive computational experience and skill on the part of the user. In order to accelerate BLAST and other sequence analysis tools, Divide and Conquer BLAST (DCBLAST was developed to perform NCBI BLAST searches within a cluster, grid, or HPC environment by using a query sequence distribution approach. Scaling from one (1 to 256 CPU cores resulted in significant improvements in processing speed. Thus, DCBLAST dramatically accelerates the execution of BLAST searches using a simple, accessible, robust, and parallel approach. DCBLAST works across multiple nodes automatically and it overcomes the speed limitation of single-node BLAST programs. DCBLAST can be used on any HPC system, can take advantage of hundreds of nodes, and has no output limitations. This freely available tool simplifies distributed computation pipelines to facilitate the rapid discovery of sequence similarities between very large data sets.

  11. Blast-induced traumatic brain injury: a new trend of blast injury research.

    Science.gov (United States)

    Zhao, Yan; Wang, Zheng-Guo

    2015-01-01

    Blast injury has become the major life- and function-threatening injuries in recent warfares. There is increased research interest in the mental disorders caused by blast-induced traumatic brain injury (bTBI), which has been proved as one of the "signature wounds" in modern battlefield. We reviewed the recent progresses in bTBI-related researches and concluded that the new era of blast injury research has shifted from the traditional physical impairments to cognitive dysfunctional/mental disorders that are proved to be more related to the outcome of combat casualty care.

  12. New techniques for improved performance in surface blasting operation and optimisation of blast design parameters

    Energy Technology Data Exchange (ETDEWEB)

    Roy, P.P. [Central Mining Research Institute, Dhanbad (India). Blasting Dept.

    1999-02-01

    Experimental blasts were conducted for optimisation of blasting parameters using separate technologies involving non-electric initiation systems, air decking accessories in conjunction with different explosive products like emulsion (cartridge and site-mixed), slurries (cartridge and site-mixed) and ANFO. The cost associated with each such technology was then compared with the conventional methods of drilling and blasting operations. The results of cost analyses are given. Theoretical and practical aspects of such technologies and their best possible usage in order to establish the desired fragmentation, muck profile, wall control and ultimately the accepted level of costs are mentioned in subsequent sections. 16 refs., 17 figs., 8 plates, 11 tabs.

  13. Quantum electrodynamics with unstable vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Fradkin, E.S. (P.N. Lebedev Physical Inst., USSR Academy of Sciences, Moscow (USSR)); Gitman, D.M. (Moscow Inst. of Radio Engineering Electronics and Automation (USSR)); Shvartsman, Sh.M. (Tomsk State Pedagogical Inst. (USSR))

    1991-01-01

    Intense external fields destabilize vacuum inducing the creation of particle pairs. In this book the formalism of quantum electrodynamics (QED), using a special perturbation theory with matrix propagators, is systematically analyzed for such systems. The developed approach is, however, general for any quantum field with unstable vacuum. The authors propose solutions for real pair-creating fields. They discuss the general form for the causal function and many other Green's functions, as well as methods for finding them. Analogies to the optical theorem and rules for computing total probabilities are given, as are solutions for non-Abelian theories. (orig.).

  14. QED vacuum loops and inflation

    Energy Technology Data Exchange (ETDEWEB)

    Fried, H.M. [Brown University, Department of Physics, Providence, RI (United States); Gabellini, Y. [UMR 6618 CNRS, Institut Non Lineaire de Nice, Valbonne (France)

    2015-03-01

    A QED-based model of a new version of vacuum energy has recently been suggested, which leads to a simple, finite, one parameter representation of dark energy. An elementary, obvious, but perhaps radical generalization is then able to describe both dark energy and inflation in the same framework of vacuum energy. One further, obvious generalization then leads to a relation between inflation and the big bang, to the automatic inclusion of dark matter, and to a possible understanding of the birth (and death) of a universe. (orig.)

  15. QED vacuum loops and inflation

    International Nuclear Information System (INIS)

    Fried, H.M.; Gabellini, Y.

    2015-01-01

    A QED-based model of a new version of vacuum energy has recently been suggested, which leads to a simple, finite, one parameter representation of dark energy. An elementary, obvious, but perhaps radical generalization is then able to describe both dark energy and inflation in the same framework of vacuum energy. One further, obvious generalization then leads to a relation between inflation and the big bang, to the automatic inclusion of dark matter, and to a possible understanding of the birth (and death) of a universe. (orig.)

  16. FastBLAST: homology relationships for millions of proteins.

    Directory of Open Access Journals (Sweden)

    Morgan N Price

    Full Text Available BACKGROUND: All-versus-all BLAST, which searches for homologous pairs of sequences in a database of proteins, is used to identify potential orthologs, to find new protein families, and to provide rapid access to these homology relationships. As DNA sequencing accelerates and data sets grow, all-versus-all BLAST has become computationally demanding. METHODOLOGY/PRINCIPAL FINDINGS: We present FastBLAST, a heuristic replacement for all-versus-all BLAST that relies on alignments of proteins to known families, obtained from tools such as PSI-BLAST and HMMer. FastBLAST avoids most of the work of all-versus-all BLAST by taking advantage of these alignments and by clustering similar sequences. FastBLAST runs in two stages: the first stage identifies additional families and aligns them, and the second stage quickly identifies the homologs of a query sequence, based on the alignments of the families, before generating pairwise alignments. On 6.53 million proteins from the non-redundant Genbank database ("NR", FastBLAST identifies new families 25 times faster than all-versus-all BLAST. Once the first stage is completed, FastBLAST identifies homologs for the average query in less than 5 seconds (8.6 times faster than BLAST and gives nearly identical results. For hits above 70 bits, FastBLAST identifies 98% of the top 3,250 hits per query. CONCLUSIONS/SIGNIFICANCE: FastBLAST enables research groups that do not have supercomputers to analyze large protein sequence data sets. FastBLAST is open source software and is available at http://microbesonline.org/fastblast.

  17. Drilling-and-blasting method of demolition

    Directory of Open Access Journals (Sweden)

    Sinitsyn Denis

    2018-01-01

    Full Text Available This article analyzes the experience and gives the examples of dismantling and demolition of the construction structures of the buildings and facilities using the drilling-and-blasting method. The drilling-and-blasting method is widely used in construction and reconstruction. The demolition means may be classified according to impact on a material of structures to be demolished and to forces application, where, by virtue of an impact energy type, we choose the blasting method. This method is used during the complete demolition or fragmentation of concrete, reinforced concrete, masonry structures, of old buildings and facilities demolition to their base or in the intended direction. Blasting method may be used as well during the steel and reinforced concrete structures demolition to the smaller easy-to-move parts. Reviewed are the organizational-process activities, which are performed during the various structures dismantling. Given are the areas of application for the various methods of structures demolition. Given is the example of demolition of “Sevemaya” boiler house brick chimney at the territory of Murmansk DSK using the blast in confined spaces of the operating company. Subject of research: methods of construction structures demolition in alarm situations and acts of God. Objects: determination of the most efficient demolition methods in the present conditions of construction operations development. Materials and methods: the developed activities on the construction structures dismantling are given. Results: the most efficient methods and ways of construction structures demolition are defined. Conclusions: it is required for improvement of methods and ways of the structures drilling-and-blasting demolition.

  18. Spalling of concrete subjected to blast loading

    Directory of Open Access Journals (Sweden)

    Foglar M.

    2013-09-01

    Full Text Available This paper presents outcomes of the blast field tests of FRC and reinforced concrete specimens, which were performed in cooperation with the Czech Army corps and Police of the Czech Republic in the military training area Boletice. The numerical evaluation of the experiments focused on the spalling of concrete subjected to blast loading started after the first set of the tests, took almost 3 years and required further small-scale experiments performed in the labs of the Czech Technical University.

  19. Implementations of BLAST for parallel computers.

    Science.gov (United States)

    Jülich, A

    1995-02-01

    The BLAST sequence comparison programs have been ported to a variety of parallel computers-the shared memory machine Cray Y-MP 8/864 and the distributed memory architectures Intel iPSC/860 and nCUBE. Additionally, the programs were ported to run on workstation clusters. We explain the parallelization techniques and consider the pros and cons of these methods. The BLAST programs are very well suited for parallelization for a moderate number of processors. We illustrate our results using the program blastp as an example. As input data for blastp, a 799 residue protein query sequence and the protein database PIR were used.

  20. Dry blasting decontaminating method for radioactive waste

    International Nuclear Information System (INIS)

    Nishiwaki, Hitoshi.

    1993-01-01

    In the present invention, when abrasives are dry blasted on the surface of radioactive wastes and the recovered abrasives are classified for re-use, abrasives having a microvicker's hardness (HMV) of greater than 600 and a grain size of greater than 1mm are used in a case where the radioactive wastes to be abraded are stainless steels. This enables dry blasting decontamination for stainless steels which has been considered to be impossible. In addition since the amount of secondary wastes are reduced, it is extremely effective. (T.M.)

  1. Predictive control of thermal state of blast furnace

    Science.gov (United States)

    Barbasova, T. A.; Filimonova, A. A.

    2018-05-01

    The work describes the structure of the model for predictive control of the thermal state of a blast furnace. The proposed model contains the following input parameters: coke rate; theoretical combustion temperature, comprising: natural gas consumption, blasting temperature, humidity, oxygen, blast furnace cooling water; blast furnace gas utilization rate. The output parameter is the cast iron temperature. The results for determining the cast iron temperature were obtained following the identification using the Hammerstein-Wiener model. The result of solving the cast iron temperature stabilization problem was provided for the calculated values of process parameters of the target area of the respective blast furnace operation mode.

  2. Gases and vacua handbook of vacuum physics

    CERN Document Server

    Beck, A H

    2013-01-01

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

  3. The Source of the Quantum Vacuum

    Directory of Open Access Journals (Sweden)

    Daywitt W. C.

    2009-01-01

    Full Text Available The quantum vacuum consists of virtual particles randomly appearing and disappearing in free space. Ordinarily the wavenumber (or frequency spectrum of the zero-point fields for these virtual particles is assumed to be unbounded. The unbounded nature of the spectrum leads in turn to an infinite energy density for the quantum vacuum and an infinite renormalization mass for the free particle. This paper argues that there is a more fundamental vacuum state, the Planck vacuum, from which the quantum vacuum emerges and that the “graininess” of this more fundamental vacuum state truncates the wavenumber spectrum and leads to a finite energy density and a finite renormalization mass.

  4. The Source of the Quantum Vacuum

    Directory of Open Access Journals (Sweden)

    Daywitt W. C.

    2009-01-01

    Full Text Available The quantum vacuum consists of virtual particles randomly appearing and disappearing in free space. Ordinarily the wavenumber (or frequency spectrum of the zero-point fields for these virtual particles is assumed to be unbounded. The unbounded nature of the spectrum leads in turn to an infinite energy density for the quantum vacuum and an infinite renormalization mass for the free particle. This paper argues that there is a more fundamental vacuum state, the Planck vacuum, from which the quantum vacuum emerges and that the "graininess" of this more fundamental vacuum state truncates the wavenumber spectrum and leads to a finite energy density and a finite renormalization mass.

  5. Low-cost blast wave generator for studies of hearing loss and brain injury: blast wave effects in closed spaces.

    Science.gov (United States)

    Newman, Andrew J; Hayes, Sarah H; Rao, Abhiram S; Allman, Brian L; Manohar, Senthilvelan; Ding, Dalian; Stolzberg, Daniel; Lobarinas, Edward; Mollendorf, Joseph C; Salvi, Richard

    2015-03-15

    Military personnel and civilians living in areas of armed conflict have increased risk of exposure to blast overpressures that can cause significant hearing loss and/or brain injury. The equipment used to simulate comparable blast overpressures in animal models within laboratory settings is typically very large and prohibitively expensive. To overcome the fiscal and space limitations introduced by previously reported blast wave generators, we developed a compact, low-cost blast wave generator to investigate the effects of blast exposures on the auditory system and brain. The blast wave generator was constructed largely from off the shelf components, and reliably produced blasts with peak sound pressures of up to 198dB SPL (159.3kPa) that were qualitatively similar to those produced from muzzle blasts or explosions. Exposure of adult rats to 3 blasts of 188dB peak SPL (50.4kPa) resulted in significant loss of cochlear hair cells, reduced outer hair cell function and a decrease in neurogenesis in the hippocampus. Existing blast wave generators are typically large, expensive, and are not commercially available. The blast wave generator reported here provides a low-cost method of generating blast waves in a typical laboratory setting. This compact blast wave generator provides scientists with a low cost device for investigating the biological mechanisms involved in blast wave injury to the rodent cochlea and brain that may model many of the damaging effects sustained by military personnel and civilians exposed to intense blasts. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Vacuum-insulated catalytic converter

    Science.gov (United States)

    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.

  7. Investigations of Pulsed Vacuum Gap.

    Science.gov (United States)

    1981-02-10

    Violet Spectra of Hot Sparks in Hh’Iacua, ’ ?hys. Rev., Vol. 12, p. 167, (1913). 31A Maitland , "Spark CondiiIoning Equation for Olane ElectrodesI-in...Appl. Phys., Vol. 1, 1291 G. Thecohilus, K. Srivastava, and R. ’ ian Heeswi.k, ’tn-situ Observation of !Microparticles in a Vacuum-Tnsulated Gap Using

  8. PC driven integrated vacuum system

    International Nuclear Information System (INIS)

    Curuia, M.; Culcer, M.; Brandea, I.; Anghel, M.

    2001-01-01

    The paper presents a integrated vacuum system which was designed and manufactured in our institute. The main parts of this system are the power supply unit for turbo-melecular pumps and the vacuummeter. Both parts of the system are driven by means of a personal computer using a serial communication, according to the RS 232 hardware standard.(author)

  9. Vacuum therapy for chronic wounds

    Directory of Open Access Journals (Sweden)

    Ekaterina Leonidovna Zaytseva

    2012-09-01

    Full Text Available Chronic wound in patients with diabetes mellitus (DM is one of the most urgent problems of modern diabetology and surgery. Numberof patients suffering from different types of chronic wounds follows increase in DM incidence. Vacuum therapy is a novel perspectivemethod of topical treatment for non-healing chronic wounds of various etiology. Current review addresses experimental and clinicalevidence for this method.

  10. Filling the vacuum at LHCb

    CERN Multimedia

    Katarina Anthony

    2013-01-01

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

  11. Nineteen-Foot Diameter Explosively Driven Blast Simulator; TOPICAL

    International Nuclear Information System (INIS)

    VIGIL, MANUEL G.

    2001-01-01

    This report describes the 19-foot diameter blast tunnel at Sandia National Laboratories. The blast tunnel configuration consists of a 6 foot diameter by 200 foot long shock tube, a 6 foot diameter to 19 foot diameter conical expansion section that is 40 feet long, and a 19 foot diameter test section that is 65 feet long. Therefore, the total blast tunnel length is 305 feet. The development of this 19-foot diameter blast tunnel is presented. The small scale research test results using 4 inch by 8 inch diameter and 2 foot by 6 foot diameter shock tube facilities are included. Analytically predicted parameters are compared to experimentally measured blast tunnel parameters in this report. The blast tunnel parameters include distance, time, static, overpressure, stagnation pressure, dynamic pressure, reflected pressure, shock Mach number, flow Mach number, shock velocity, flow velocity, impulse, flow duration, etc. Shadowgraphs of the shock wave are included for the three different size blast tunnels

  12. A computational model of blast loading on the human eye.

    Science.gov (United States)

    Bhardwaj, Rajneesh; Ziegler, Kimberly; Seo, Jung Hee; Ramesh, K T; Nguyen, Thao D

    2014-01-01

    Ocular injuries from blast have increased in recent wars, but the injury mechanism associated with the primary blast wave is unknown. We employ a three-dimensional fluid-structure interaction computational model to understand the stresses and deformations incurred by the globe due to blast overpressure. Our numerical results demonstrate that the blast wave reflections off the facial features around the eye increase the pressure loading on and around the eye. The blast wave produces asymmetric loading on the eye, which causes globe distortion. The deformation response of the globe under blast loading was evaluated, and regions of high stresses and strains inside the globe were identified. Our numerical results show that the blast loading results in globe distortion and large deviatoric stresses in the sclera. These large deviatoric stresses may be indicator for the risk of interfacial failure between the tissues of the sclera and the orbit.

  13. Blast noise classification with common sound level meter metrics.

    Science.gov (United States)

    Cvengros, Robert M; Valente, Dan; Nykaza, Edward T; Vipperman, Jeffrey S

    2012-08-01

    A common set of signal features measurable by a basic sound level meter are analyzed, and the quality of information carried in subsets of these features are examined for their ability to discriminate military blast and non-blast sounds. The analysis is based on over 120 000 human classified signals compiled from seven different datasets. The study implements linear and Gaussian radial basis function (RBF) support vector machines (SVM) to classify blast sounds. Using the orthogonal centroid dimension reduction technique, intuition is developed about the distribution of blast and non-blast feature vectors in high dimensional space. Recursive feature elimination (SVM-RFE) is then used to eliminate features containing redundant information and rank features according to their ability to separate blasts from non-blasts. Finally, the accuracy of the linear and RBF SVM classifiers is listed for each of the experiments in the dataset, and the weights are given for the linear SVM classifier.

  14. Regulating vacuum pump speed with feedback control

    International Nuclear Information System (INIS)

    Ludington, D.C.; Aneshansley, D.J.; Pellerin, R.; Guo, F.

    1992-01-01

    Considerable energy is wasted by the vacuum pump/motor on dairy farms. The output capacity (m 3 /min or cfm) of the vacuum pump always exceeds the capacity needed to milk cows and wash pipelines. Vacuum pumps run at full speed and load regardless of actual need for air. Excess air is admitted through a controller. Energy can be saved from electrical demand reduced by regulating vacuum pump speed according to air based on air usage. An adjustable speed drive (ASD) on the motor and controlled based upon air usage, can reduce the energy used by the vacuum pump. However, the ASD unit tested could not maintain vacuum levels within generally accepted guidelines when air usage changed. Adding a high vacuum reserve and a dual vacuum controller between the vacuum pump and the milking pipeline brought vacuum stability within guidelines. The ASD/dual vacuum system can reduce energy consumption and demand by at least 50 percent during milking and provide better vacuum stability than conventional systems. Tests were not run during washing cycles. Using 1990 costs and only the energy saved during milking, the simple payback on investment in new equipment for a 5 hp motor, speed controller and vacuum regulator would be about 5 years

  15. Vacuum polarization and Hawking radiation

    Science.gov (United States)

    Rahmati, Shohreh

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

  16. Compactified vacuum in ten dimensions

    International Nuclear Information System (INIS)

    Wurmser, D.

    1987-01-01

    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 by 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. The authors 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. He 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 examples M 4 x 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 test for any theory which predicts a compactified vacuum

  17. Consideration on local blast vibration control by delay blasting; Danpatsu happa ni yoru kyokuchiteki shindo seigyo ni kansuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Mogi, Gento; Adachi, Tsuyoshi; Yamatomi, Jiro [The University of Tokyo School of Engineering Department of Geosystem Engineering, Tokyo (Japan); Hoshino, Tatsuya [Mitsui Mining and Smelting Corp., Tokyo (Japan)

    1999-10-31

    In this research, local blast vibration control based on the theory of superposition of waves was investigated. Firstly, the influence of delay time errors of conventional electric detonators upon the level of local blast vibration was examined. Secondly, for a further effective local blast vibration control, a new delay blasting design concept 'combined delay blasting' that postulates the use of electronic detonators, which virtually have no delay time errors, is proposed. For a delay blasting with uniform detonation time intervals, an optimum time interval to minimize the local PPV (Peak Particle Velocity) is obtained based on the relationship between the PPV and the time interval, which is derived by superposing identical vibration time histories of each single hole shot. However, due to the scattering of the actual delay time caused by errors, PPV of a production blast seldom coincides with the estimated one. Since the expected value and the variance of PPV mainly depend on sensitivity of PPV around the nominal delay time, it is proposed that not only the optimum but also several sub-optimum candidates of delay time should be examined taking error into consideration. Concerning the 'combined delay blasting', its concept and some simulation results are presented. The estimated reduction effect of blast vibration of a delay blast based on this concept was quite favorable, indicating a possibility for further effective local blast vibration control. (author)

  18. Gauge field vacuum structure in geometrical aspect

    International Nuclear Information System (INIS)

    Konopleva, N.P.

    2003-01-01

    Vacuum conception is one of the main conceptions of quantum field theory. Its meaning in classical field theory is also very profound. In this case the vacuum conception is closely connected with ideas of the space-time geometry. The global and local geometrical space-time conceptions lead to different vacuum definitions and therefore to different ways of physical theory construction. Some aspects of the gauge field vacuum structure are analyzed. It is shown that in the gauge field theory the vacuum Einstein equation solutions describe the relativistic vacuum as common vacuum of all gauge fields and its sources. Instantons (both usual and hyperbolical) are regarded as nongravitating matter, because they have zero energy-momentum tensors and correspond to vacuum Einstein equations

  19. Characteristics of the ISABELLE vacuum system

    International Nuclear Information System (INIS)

    Aggus, J.R.; Edwards, D. Jr.; Halama, H.J.; Herrera, J.C.

    1977-01-01

    A discussion is given of the complete vacuum system of ISABELLE, emphasizing those design characteristics dictated by high vacuum, the avoidance of beam current loss, and the reduction of background. The experimental and theoretical justifications for the design are presented

  20. 8 Museve NBI BombBlast.indd

    African Journals Online (AJOL)

    Professionals, executives, managers, semi professionals and skilled workers comprised 89.5% of the victims when ... dependants. Being inside a building and within 100 metres from the blast carried the largest risk of injury. A ... Kenya had never experienced a suicidal terrorist bombing ..... Rapid assessment of Injuries.

  1. Ice blasting device for washing pump

    International Nuclear Information System (INIS)

    Hirose, Yasuo.

    1992-01-01

    In a nuclear power plant, when the inside of a pump casing such as a recycling pump is scrubbed, since operator's safety should be ensured, it requires a large-scaled operation. Then, a cover is attached to a flange of the pump casing, in which a driving portion is disposed passing through the cover vertically movably and rotatably, an arm is disposed bendably to the top end of the arm, and a blast nozzle is disposed to the top end of the arm for jetting ice particles, with a camera being disposed to the blast nozzle. The inside of the casing can be scrubbed safely and rapidly by an ice blast method by remote operation while monitoring the state of scrubbing for the inside of the casing by a camera. Further, since the flange of the pump casing for installing the ice blast device is covered by the cover, mists are not scattered to the outside. In addition, mists may be sucked and removed by an exhaustion duct. (N.H.)

  2. Modeling of Near-Field Blast Performance

    Science.gov (United States)

    2013-11-01

    The freeze-out temperature is chosen by comparison of calorimetry experiments (2, 3) and thermoequilibrium calculations using CHEETAH (4). The near...P.; Vitello, P. CHEETAH Users Manual; Lawrence Livermore National Laboratory: Livermore, CA, 2012. 5. Walter, P. Introduction to Air Blast

  3. Blast Injuries: What Clinicians Need to Know

    Centers for Disease Control (CDC) Podcasts

    In this podcast, Dr. Richard C. Hunt, Director of the CDC’s Division of Injury Response, National Center for Injury Prevention and Control provides a brief overview for health care providers on how to respond and care for persons injured by an explosion or blast event.

  4. Distinguishing Realistic Military Blasts from Firecrackers in Mitigation Studies of Blast Induced Traumatic Brain Injury

    Energy Technology Data Exchange (ETDEWEB)

    Moss, W C; King, M J; Blackman, E G

    2011-01-21

    In their Contributed Article, Nyein et al. (1,2) present numerical simulations of blast waves interacting with a helmeted head and conclude that a face shield may significantly mitigate blast induced traumatic brain injury (TBI). A face shield may indeed be important for future military helmets, but the authors derive their conclusions from a much smaller explosion than typically experienced on the battlefield. The blast from the 3.16 gm TNT charge of (1) has the following approximate peak overpressures, positive phase durations, and incident impulses (3): 10 atm, 0.25 ms, and 3.9 psi-ms at the front of the head (14 cm from charge), and 1.4 atm, 0.32 ms, and 1.7 psi-ms at the back of a typical 20 cm head (34 cm from charge). The peak pressure of the wave decreases by a factor of 7 as it traverses the head. The blast conditions are at the threshold for injury at the front of the head, but well below threshold at the back of the head (4). The blast traverses the head in 0.3 ms, roughly equal to the positive phase duration of the blast. Therefore, when the blast reaches the back of the head, near ambient conditions exist at the front. Because the headform is so close to the charge, it experiences a wave with significant curvature. By contrast, a realistic blast from a 2.2 kg TNT charge ({approx} an uncased 105 mm artillery round) is fatal at an overpressure of 10 atm (4). For an injury level (4) similar to (1), a 2.2 kg charge has the following approximate peak overpressures, positive phase durations, and incident impulses (3): 2.1 atm, 2.3 ms, and 18 psi-ms at the front of the head (250 cm from charge), and 1.8 atm, 2.5 ms, and 16.8 psi-ms at the back of the head (270 cm from charge). The peak pressure decreases by only a factor of 1.2 as it traverses the head. Because the 0.36 ms traversal time is much smaller than the positive phase duration, pressures on the head become relatively uniform when the blast reaches the back of the head. The larger standoff implies

  5. 29 CFR 1926.906 - Initiation of explosive charges-electric blasting.

    Science.gov (United States)

    2010-07-01

    ...) After firing an electric blast from a blasting machine, the leading wires shall be immediately... 29 Labor 8 2010-07-01 2010-07-01 false Initiation of explosive charges-electric blasting. 1926.906... Use of Explosives § 1926.906 Initiation of explosive charges—electric blasting. (a) Electric blasting...

  6. Oil injection into the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Dongsheng Liao; Mannila, P.; Haerkki, J.

    1997-12-31

    Fuel injection techniques have been extensively used in the commercial blast furnaces, a number of publications concerning the fuels injection have been reported. This present report only summarizes the study achievements of oil injection due to the research need the of authors, it includes the following parts: First, the background and the reasons reducing coke rate of oil injection are analyzed. Reducing coke rate and decreasing the ironmaking costs are the main deriving forces, the contents of C, H and ash are direct reasons reducing coke rate. It was also found that oil injection had great effects on the state of blast furnace, it made operation stable, center gas flow develop fully, pressure drop increase, descent speed of burden materials decrease and generation of thermal stagnation phenomena, the quality of iron was improved. Based on these effects, as an ideal mean, oil injection was often used to adjust the state of blast furnace. Secondly, combustion behavior of oil in the raceway and tuyere are discussed. The distribution of gas content was greatly changed, the location of CO, H{sub 2} generation was near the tuyere; the temperature peak shifts from near the raceway boundary to the tuyere. Oxygen concentration and blast velocity were two important factors, it was found that increasing excess oxygen ratio 0.9 to 1.3, the combustion time of oil decreases 0.5 msec, an increase of the blast velocity results in increasing the flame length. In addition, the nozzle position and oil rate had large effects on the combustion of oil. Based on these results, the limit of oil injection is also discussed, soot formation is the main reason limiting to further increase oil injection rate, it was viewed that there were three types of soot which were generated under blast furnace operating conditions. The reason generating soot is the incomplete conversion of the fuel. Finally, three methods improving combustion of oil in the raceway are given: Improvement of oil

  7. Research on vacuum insulation for cryocables

    International Nuclear Information System (INIS)

    Graneau, P.

    1974-01-01

    Vacuum insulation, as compared with solid insulation, simplifies the construction of both resistive or superconducting cryogenic cables. The common vacuum space in the cable can furnish thermal insulation between the environment and the cryogenic coolant, provide electrical insulation between conductors, and establish thermal isolation between go- and return-coolant streams. The differences between solid and vacuum high voltage insulation are discussed, and research on the design, materials selection, and testing of vacuum insulated cryogenic cables is described

  8. Color-magnetic permeability of QCD vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Saito, T [Kyoto Prefectural Univ. of Medicine (Japan); Shigemoto, K

    1980-03-01

    In the very strong background gauge field the QCD true vacuum has been shown to have lower energy than the ''perturbative vacuum.'' The color-magnetic permeability of the QCD true vacuum is then calculated to be 1/2 within the quark-one-loop approximation.

  9. 46 CFR 154.804 - Vacuum protection.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Vacuum protection. 154.804 Section 154.804 Shipping... Systems § 154.804 Vacuum protection. (a) Except as allowed under paragraph (b) of this section, each cargo tank must have a vacuum protection system meeting paragraph (a)(1) of this section and either paragraph...

  10. Blasting as a method for abandoned mine land reclamation

    International Nuclear Information System (INIS)

    Workman, J.L.; Fletcher, L.R.

    1991-01-01

    Blasting methods have been proposed for reclaiming abandoned underground coal mine sites having unstable conditions. The objective of blasting is twofold: the permanent stabilization of an area by the collapse of underground workings to prevent any future subsidence, and the use of blasting to close existing sinkholes. This paper presents the results of two research projects funded by the Bureau of Mines Abandoned Mine Land Research Program to investigate the feasibility of blasting to assist in the reclamation of shallow abandoned coal mine sites. Blasting tests were conducted at Beulah, North Dakota and at Scobey, Montana, involving different configurations. The first test was a 10-acre site where blasting was used to collapse regular room and pillar panels for which good mine layout information was available. The second test involved a one acre site containing very irregular workings for which there was little available information. Finally, blasting techniques were used to close 13 individual vertical openings. The depths to the coal seams were 60 feet or less at all sites. When blasting for Abandoned Mine Land Reclamation, material must be cast downward into the abandoned developments or laterally into the sinkhole. Designs based on cratering concepts and spherical charges worked well. The blasting techniques successfully collapsed and stabilized the test areas. Cost of reclamation for the two test sites are presented. Data from blast vibration monitoring are presented because control of vibrations is of concern when mitigation efforts are conducted near homes

  11. "Flat-Fish" Vacuum Chamber

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

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

  12. LEP vacuum chamber, early prototype

    CERN Multimedia

    CERN PhotoLab

    1978-01-01

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

  13. Deflated-Victims of vacuum

    International Nuclear Information System (INIS)

    Sanders, Roy E.

    2007-01-01

    Atmospheric pressure combined with a partial vacuum within chemical plant or refinery tanks can result in some ego-deflating moments. This article will review three catastrophic vessel failures in detail and touch on several other incidents. A 4000-gal acid tank was destroyed by a siphoning action; a well maintained tank truck was destroyed during a routine delivery; and a large, brand new refinery mega-vessel collapsed as the steam within it condensed. Seasoned engineers are aware of the frail nature of tanks and provide safeguards or procedures to limit damages. The purpose of this paper is to ensure this new generation of chemical plant/refinery employees understand the problems of the past and take the necessary precautions to guard against tank damages created by partial vacuum conditions

  14. Mirror Fusion vacuum technology developments

    International Nuclear Information System (INIS)

    Batzer, T.H.; Call, W.R.

    1983-01-01

    Magnetic Mirror Fusion experiments, such as MFTF-B+T (Mirror Fusion Test Facility-B, Tritium Upgrade) and foreseeable follow-on devices, have operational and maintenance requirements that have not yet been fully demonstrated. Among those associated with vacuum technology are the very-high continuous-pumping speeds, 10 7 to 10 8 l/s for D 2 , T 2 and, to a lesser extent, He; the early detection of water leaks from the very-high heat-flux neutral-beam dumps and the detection and location of leaks in the superconducting magnets not protected by guard vacuums. Possible solutions to these problems have been identified and considerable progress has been made toward successfully demonstrating their feasibility

  15. Mirror fusion vacuum technology developments

    International Nuclear Information System (INIS)

    Batzer, T.H.; Call, W.R.

    1983-01-01

    Magnetic Mirror Fusion experiments, such as MFTF-B+T (Mirror Fusion Test Facility-B, Tritium Upgrade) and foreseeable follow-on devices, have operational and maintenance requirements that have not yet been fully demonstrated. Among those associated with vacuum technology are the very-high continuous-pumping speeds, 10 7 to 10 8 l/s for D 2 , T 2 and, to a lesser extent, He; the early detection of water leaks from the very-high heat-flux neutral-beam dumps and the detection and location of leaks in the superconducting magnets not protected by guard vacuums. Possible solutions to these problems have been identified and considerable progress has been made toward successfully demonstrating their feasibility

  16. Quantum friction across the vacuum

    International Nuclear Information System (INIS)

    Ebelein, C.

    1998-01-01

    Friction is so ubiquitous that it seems to be almost trivially familiar. The rubbing of two solid surfaces is opposed by a resistance and accompanied by the production of heat. Engineers still dream of perfectly smooth surfaces that can be moved against each other without any friction. However, this dream has now been shattered by John Pendry of Imperial College, London, who has published a theory that shows that even two perfectly smooth surfaces can experience an appreciable friction when moved relative to each other (J. Phys.: Condens. Matter 1997 9 10301-10320). Moreover, the two surfaces he considers are not even in contact but separated by a gap a lattice constant or so wide. The explanation of this lies in what Pendry calls the shearing of the vacuum in the gap. In quantum physics the vacuum is not just empty nothingness; it is full of virtually everything. The vacuum abounds with virtual photons. These zero-point fluctuations cannot normally be seen, but they give the vacuum a structure that manifests itself in a variety of effects (for example, the Casimir effect). A more subtle, yet more familiar, manifestation of these zero-point fluctuations is the van der Waals force. The effect described by Pendry can be understood as a van der Waals interaction between two infinite slabs of dielectric material moving relative to each other. Each slab will be aware of the motion of the other because the virtual photons reflected from the moving surface are Doppler-shifted up or down, depending on the direction of the photon wave vector relative to the motion. Pendry shows that this asymmetry in the exchange of virtual photons can lead to an appreciable effect for materials of reasonably strong dispersion. (author)

  17. Random numbers from vacuum fluctuations

    International Nuclear Information System (INIS)

    Shi, Yicheng; Kurtsiefer, Christian; Chng, Brenda

    2016-01-01

    We implement a quantum random number generator based on a balanced homodyne measurement of vacuum fluctuations of the electromagnetic field. The digitized signal is directly processed with a fast randomness extraction scheme based on a linear feedback shift register. The random bit stream is continuously read in a computer at a rate of about 480 Mbit/s and passes an extended test suite for random numbers.

  18. Acceleration of plasma into vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, John [Los Alamos Scientific Laboratory, University of California, Los Alamos, NM (United States)

    1958-07-01

    The first part of this paper is a discussion of the magnetic acceleration of plasma. The second part contains a description of some experiments which have been performed. In the work reported the intention is: 1. To produce a burst of gas in vacuo; 2. To ionize the gas and heat it to such an extent that it becomes a good electrical conductor. 3. To accelerate the plasma thus produced into vacuum by the use of external time-varying magnetic fields.

  19. Random numbers from vacuum fluctuations

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yicheng; Kurtsiefer, Christian, E-mail: christian.kurtsiefer@gmail.com [Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Center for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore); Chng, Brenda [Center for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore)

    2016-07-25

    We implement a quantum random number generator based on a balanced homodyne measurement of vacuum fluctuations of the electromagnetic field. The digitized signal is directly processed with a fast randomness extraction scheme based on a linear feedback shift register. The random bit stream is continuously read in a computer at a rate of about 480 Mbit/s and passes an extended test suite for random numbers.

  20. Vacuum evaporation of pure metals

    OpenAIRE

    Safarian, Jafar; Engh, Thorvald Abel

    2013-01-01

    Theories on the evaporation of pure substances are reviewed and applied to study vacuum evaporation of pure metals. It is shown that there is good agreement between different theories for weak evaporation, whereas there are differences under intensive evaporation conditions. For weak evaporation, the evaporation coefficient in Hertz-Knudsen equation is 1.66. Vapor velocity as a function of the pressure is calculated applying several theories. If a condensing surface is less than one collision...

  1. Vacuum mammotomy under ultrasound guidance

    International Nuclear Information System (INIS)

    Luczynska, E.; Kocurek, A.; Pawlik, T.; Aniol, J.; Herman, K.; Skotnicki, P.

    2007-01-01

    Breast ultrasound is a non-invasive method of breast examination. You can use it also for fine needle biopsy, core needle biopsy, vacuum mammotomy and for placing the '' wire '' before open surgical biopsy. 106 patients (105 women and 1 man) aged 20-71 years (mean age 46.9) were treated in Cancer Institute in Cracow by vacuum mammotomy under ultrasound guidance. The lesions found in ultrasonography were divided into three groups: benign lesions (BI RADS II), ambiguous lesions (BI RADS 0, III and IVa), and suspicious lesions (BI RADS IV B, IV C and V). Then lesions were qualified to vacuum mammotomy. According to USG, fibroadenoma or '' fibroadenoma-like '' lesions were found in 75 women, in 6 women complicated cysts, in 6 women cyst with dense fluid (to differentiate with FA), and in 19 patients undefined lesions. Fibroadenoma was confirmed in histopathology in 74% patients among patients with fibroadenoma or '' fibroadenoma-like '' lesions in ultrasound (in others also benign lesions were found). Among lesions undefined after ultrasound examination (total 27 patients) cancer was confirmed in 6 % (DCIS and IDC). In 6 patients with complicated cysts in ultrasound examination, histopathology confirmed fibroadenoma in 4 women, an intraductal lesion in 1 woman and inflamatory process in 1 woman. Also in 6 women with a dense cyst or fibroadenoma seen in ultrasound, histopathology confirmed fibroadenoma in 3 women and fibrosclerosis in 3 women. Any breast lesions undefined or suspicious after ultrasound examination should be verified. The method of verification or kind of operation of the whole lesion (vacuum mammotomy or '' wire '') depends on many factors, for example: lesion localization; lesion size; BI RADS category. (author)

  2. QCD contributions to vacuum polarization

    International Nuclear Information System (INIS)

    Reinders, L.J.; Rubinstein, H.R.; Yazaki, S.

    1980-01-01

    We have computed to lowest non-trivial order the perturbative and non-perturbative contributions to the vacuum polarization from all currents up to and including spin 2 ++ . These expressions are important, for example to evaluate QCD sum rules for heavy and light quark systems as shown by Shifman, Vainshtein and Zakharov. Most of the known ones are verified, one slightly changed, and many new ones are displayed. (orig.)

  3. Vacuum vessel for plasma devices

    International Nuclear Information System (INIS)

    Yamada, Masao; Taguchi, Masami.

    1975-01-01

    Object: To permit effective utility of the space in the inner and outer sides of the container wall and also permit repeated assembly for use. Structure: Vacuum vessel wall sections are sealed together by means of welding bellows, and also flange portions formed at the end of the wall sections are coupled together by bolts and are sealed together with a seal ring and a seal cap secured by welding. (Nakamura, S.)

  4. Relaxed plasma-vacuum systems

    International Nuclear Information System (INIS)

    Spies, G.O.; Lortz, D.; Kaiser, R.

    2001-01-01

    Taylor's theory of relaxed toroidal plasmas (states of lowest energy with fixed total magnetic helicity) is extended to include a vacuum between the plasma and the wall. In the extended variational problem, one prescribes, in addition to the helicity and the magnetic fluxes whose conservation follows from the perfect conductivity of the wall, the fluxes whose conservation follows from the assumption that the plasma-vacuum interface is also perfectly conducting (if the wall is a magnetic surface, then one has the toroidal and the poloidal flux in the vacuum). Vanishing of the first energy variation implies a pressureless free-boundary magnetohydrostatic equilibrium with a Beltrami magnetic field in the plasma, and in general with a surface current in the interface. Positivity of the second variation implies that the equilibrium is stable according to ideal magnetohydrodynamics, that it is a relaxed state according to Taylor's theory if the interface is replaced by a wall, and that the surface current is nonzero (at least if there are no closed magnetic field lines in the interface). The plane slab, with suitable boundary conditions to simulate a genuine torus, is investigated in detail. The relaxed state has the same double symmetry as the vessel if, and only if, the prescribed helicity is in an interval that depends on the prescribed fluxes. This interval is determined in the limit of a thin slab

  5. PC driven integrated vacuum system

    International Nuclear Information System (INIS)

    Curuia, Marian; Culcer, Mihai; Brandea, Iulian; Anghel, Mihai

    2001-01-01

    The monitoring of industrial plants by virtual instrumentation represents the most modern trend in the domain of electronic equipment. The integrated vacuum system presented here has several facilities, including the automated data storing of measurement results on hard disk and providing warning messages for operators when the measured parameters are lower or higher upper than the fixed values. The system can also work stand-alone, receiving the commands from the keyboards placed on his front panel but, when it is included in a automation complex system, a remote control from PC is necessary . Both parts of the system, power supply unit for turbo-molecular pump and the vacuum gage, are controlled by an 80C31 microcontroller. Because this microcontroller has a built-in circuitry for a serial communication, we established a serial communication between the PC and the power supply unit for turbo-molecular pump and the vacuum gage, according to the RS-232 hardware standard. As software, after careful evaluation of several options, we chose to develop a hybrid software packing using two different software development tools: LabVIEW, and assembly language. We chose LabVIEW because it is dedicated to data acquisition and communications, containing libraries for data collection, analysis, display and storage. (authors)

  6. Running jobs in the vacuum

    International Nuclear Information System (INIS)

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

    2014-01-01

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

  7. Optimization of a cascade refrigeration system using refrigerant C_3H_8 in high temperature circuits (HTC) and a mixture of C_2H_6/CO_2 in low temperature circuits (LTC)

    International Nuclear Information System (INIS)

    Nasruddin; Sholahudin, S.; Giannetti, N.; Arnas

    2016-01-01

    Highlights: • Multi-objective optimization is conducted in the cascade refrigeration system. • Combination of operating temperature and refrigerant performance has been studied. • Characteristic of C_3H_8 and a mixture of C_2H_6/CO_2 have been investigated. • Determining of CO_2 fraction to optimize refrigeration system has been done. - Abstract: This paper discusses the multi-objectives optimization of a cascade refrigeration system using refrigerant C_3H_8 in high temperature circuits (HTC) and a mixture of C_2H_6/CO_2 in low temperature circuits (LTC). The evaporator temperature, condenser temperature, C_2H_6/CO_2 mixture condensation temperature, cascade temperature differences, and the CO_2 mass fraction are chosen as the decision variables. Whereas cooling capacity, cold space temperature, and ambient temperature are taken as the constraints. The purpose of this research is to design a cascade refrigeration system whose optimum performance are defined in terms of economics and thermodynamics. Accordingly, there are two objective functions that should be simultaneously optimized including the total annual cost which consists of the capital and operational cost and the total exergy destruction of the system. To this aim, the optimum operating temperature of the system and CO_2 fraction should be determined so that the system has minimum exergy destruction and annual cost. Results show that, the optimum value of the decision variables for this system can be determined by trade-off between annual cost and exergy destruction.

  8. CAS CERN Accelerator School vacuum technology. Proceedings

    International Nuclear Information System (INIS)

    Turner, S.

    1999-01-01

    These proceedings present the lectures given at the twelfth specialized course organized by the CERN Accelerator School (CAS), the topic this time being 'Vacuum Technology'. Despite the importance of vacuum technology in the design and operation of particle accelerators at CERN and at the many other accelerators already installed around the world, this was the first time that CAS has organized a course devoted entirely to this topic. Perhaps this reflects the facts that vacuum has become one of the more critical aspects of future accelerators, and that many of the pioneers in the accelerator field are being replaced by new, younger personnel. The lectures start with the basic concepts of the physics and technology of vacuum followed by detailed descriptions of the many different types of gas-pumping devices and methods to measure the pressures achieved. The outgassing characteristics of the different materials used in the construction of vacuum systems and the optimisation of cleaning methods to reduce this outgassing are then explained together with the effects of the residual gases on the particle beams. Then follow chapters on leak detection, materials and vacuum system engineering. Finally, seminars are presented on designing vacuum systems, the history of vacuum devices, the LHC (large hadron collider) vacuum system, vacuum systems for electron storage rings, and quality assurance for vacuum. (orig.)

  9. Development of a Continuous Drill and Blast Tunneling Concept, Phase II

    Science.gov (United States)

    1974-05-01

    A spiral drilling pattern is described which offers high efficiency drill and blast tunnelling via frequent small blasts rather than occasional large blasts. Design work is presented for a machine which would stay at the face to provide essentially c...

  10. 77 FR 31878 - Agency Information Collection Activities; Submission for OMB Review; Comment Request; Blasting...

    Science.gov (United States)

    2012-05-30

    ... requirements designed to protect covered employees working with and around blasting operations. Inventories of... for OMB Review; Comment Request; Blasting Operations and Use of Explosives Standard ACTION: Notice... (OSHA) sponsored information collection request (ICR) titled, ``Blasting Operations and Use of...

  11. Rotary bayonets for cryogenic and vacuum service

    International Nuclear Information System (INIS)

    Rucinski, R.A.; Dixon, K.D.; Krasa, R.; Krempetz, K.J.; Mulholland, G.T.; Trotter, G.R.; Urbin, J.B.

    1993-07-01

    Rotary bayonets were designed, tested, and installed for liquid nitrogen, liquid argon, and vacuum service. This paper will present the design, testing, and service record for two sizes of vacuum jacketed cryogenic rotary bayonets and two sizes of vacuum service rotary bayonets. Materials used in construction provide electrical isolation across the bayonet joint. The joint permits 360 degrees of rotation between the male and female pipe sections while maintaining integrity of service. Assemblies using three such joints were built to allow end connection points to be translated through at least 1 meter of horizontal travel while kept in service. Vacuum jacketed sizes built in-house at Fermi National Accelerator Laboratory are 1-1/2 in. inner pipe size, 3 in. vacuum jacket, and 4 in. inner pipe size, 6 in. vacuum jacket The single wall vacuum service bayonets are in 4 in. and 6 in. pipe sizes. The bayonets have successfully been in active service for over one year

  12. Rotary bayonets for cryogenic and vacuum service

    International Nuclear Information System (INIS)

    Rucinski, R.A.; Dixon, K.D.; Krasa, R.; Krempetz, K.J.; Mulholland, G.T.; Trotter, G.R.; Urbin, J.B.

    1994-01-01

    Rotary bayonets were designed, tested, and installed for liquid nitrogen, liquid argon, and vacuum service. This paper will present the design, testing, and service record for two sizes of vacuum jacketed cryogenic rotary bayonets and two sizes of vacuum service rotary bayonets. Materials used in construction provide electrical isolation across the bayonet joint. The joint permits 360 degrees of rotation between the male and female pipe sections while maintaining integrity of service. Assemblies using three such joints were built to allow end connection points to be translated through at least 1 meter of horizontal travel while kept in service. Vacuum jacketed sizes built in-house at Fermi National Accelerator Laboratory are 1 1/2 inches inner pipe size, 3 inches vacuum jacket, and 4 inches inner pipe size, 6 inches vacuum jacket. The single wall vacuum service bayonets are in 4 inch and 6 inch pipe sizes. The bayonets have successfully been in active service for over one year

  13. Application of Carbon Composite Bricks for Blast Furnace Hearth

    Science.gov (United States)

    Zuo, Haibin; Wang, Cong; Zhang, Jianliang; Zhao, Yongan; Jiao, Kexin

    Traditional refractory materials for blast furnace hearth lining are mainly composed of carbon bricks and the ceramic cup. However, these materials can't meet the demands for long service life design of blast furnaces. In this paper, a new refractory called carbon composite brick (CCB) was introduced, which combined the advantages of carbon bricks and the ceramic cup. In this case, the resistance of the CCB against corrosion was equal to the ceramic cup and the thermal conductivity of the CCB was equal to carbon bricks. From the results of more than 20 blast furnaces, the CCB could be well used in small blast furnaces and large blast furnaces. In the bad condition of low grade burden and high smelting intensity, the CCB gave full play to the role of cooling system, and effectively resisted the erosion of hot metal to improve the service life of blast furnaces.

  14. Safety management system during rock blasting at FRFCF construction site

    International Nuclear Information System (INIS)

    Vijayakumaran, C.; Kandasamy, S.; Satpathy, K.K.

    2016-01-01

    Blasting is an important activity during rock excavation to reach required depth for obtaining stability of the civil structure. For the construction of various Plant Buildings of Fast Reactor Fuel Cycle Facility (FRFCF), IGCAR at Kalpakkam, based on the geological survey it is required to reach a depth of 21.4 meters from existing ground level. This paper details about the procedures and precaution adopted during the rock blasting activities at FRFCF site. The volume of rock removed by blasting was 3 lakh cubic meters. The total number of blasting carried out was 304 using 105.73 tons of blasting material. The entire blasting work could be completed within 174 days without any incident. (author)

  15. Proceedings of the seventeenth annual conference on explosives and blasting technique. Volume 1

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Papers from this conference dealt with the following topics: surface and underground mine blasting, control of blast effects in sensitive areas, blasthole deviation, regulatory impact when blasting at Superfund sites, computer-aided blast design and monitoring, tunneling techniques, shaft excavations, video camera analysis of blasting operations, soil densification, cost optimization, mine blasting accidents, non-electric initiation systems, and delay detonators. Papers have been indexed separately for inclusion on the data base

  16. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    International Nuclear Information System (INIS)

    Mahadtanapuk, S.; Teraarusiri, W.; Phanchaisri, B.; Yu, L.D.; Anuntalabhochai, S.

    2013-01-01

    Highlights: •N-ion beam bombarded Thai jasmine rice seeds to induce mutation. •Mutants with blast-disease resistance and high yield were screened. •Gene involved in the blast-disease resistance was analyzed. •The gene responsible for the resistance was linked to Spotted leaf protein 11. -- Abstract: Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60–80 keV to a beam fluence range of 2 × 10 16 –2 × 10 17 ions/cm 2 . The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 10 6 spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11)

  17. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Mahadtanapuk, S. [School of Agriculture and Natural Resources, University of Phayao, Phayao 56000 (Thailand); Teraarusiri, W. [Central Laboratory, University of Phayao, Phayao 56000 (Thailand); Phanchaisri, B. [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@frnf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Anuntalabhochai, S., E-mail: burinka@hotmail.com [Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2013-07-15

    Highlights: •N-ion beam bombarded Thai jasmine rice seeds to induce mutation. •Mutants with blast-disease resistance and high yield were screened. •Gene involved in the blast-disease resistance was analyzed. •The gene responsible for the resistance was linked to Spotted leaf protein 11. -- Abstract: Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60–80 keV to a beam fluence range of 2 × 10{sup 16}–2 × 10{sup 17} ions/cm{sup 2}. The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 10{sup 6} spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11)

  18. Pathological Fingerprints, Systems Biology and Biomarkers of Blast Brain Injury

    Science.gov (United States)

    2010-06-01

    changes after blast injury. J. Trauma 56, 393–403. Murthy, J.M., Chopra, J.S., and Gulati, D.R. (1979). Subdural hematoma in an adult following a blast...neuronal damage), diffuse brain injury, and subdural hemorrhage. It is still controversial whether primary blast forces directly damage the brain, and if...emboli, leading to infarction (Guy et al., 2000a; Guy et al., 2000b). The most common types of TBI are diffuse axonal injury, contusion, and subdural

  19. A Phased Array Approach to Rock Blasting

    Energy Technology Data Exchange (ETDEWEB)

    Leslie Gertsch; Jason Baird

    2006-07-01

    A series of laboratory-scale simultaneous two-hole shots was performed in a rock simulant (mortar) to record the shock wave interference patterns produced in the material. The purpose of the project as a whole was to evaluate the usefulness of phased array techniques of blast design, using new high-precision delay technology. Despite high-speed photography, however, we were unable to detect the passage of the shock waves through the samples to determine how well they matched the expected interaction geometry. The follow-up mine-scale tests were therefore not conducted. Nevertheless, pattern analysis of the vectors that would be formed by positive interference of the shockwaves from multiple charges in an ideal continuous, homogeneous, isotropic medium indicate the potential for powerful control of blast design, given precise characterization of the target rock mass.

  20. Proceedings of the eighteenth annual conference on explosives and blasting technique

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    This edition of the Proceedings of the Annual Conference on Explosives and Blasting Techniques is the eighteenth in a series published by the International Society of Explosives Engineers. The papers cover a wide variety of explosives and blasting techniques, including: rock mechanics, rock drilling, perimeter control handling and documenting blasting complaints, blast vibration frequencies, blasting techniques for surface and underground coal mines, explosives for permafrost blasting, lightning detection, use of slow motion video to analyze blasts, tunneling, and close-in blasting control. Papers have been processed individually for inclusion on the data base

  1. Experimental Study and Engineering Practice of Pressured Water Coupling Blasting

    Directory of Open Access Journals (Sweden)

    J. X. Yang

    2017-01-01

    Full Text Available Overburden strata movement in large space stope is the major reason that induces the appearance of strong mining pressure. Presplitting blasting for hard coal rocks is crucial for the prevention and control of strong pressure in stope. In this study, pressured water coupling blasting technique was proposed. The process and effect of blasting were analyzed by orthogonal test and field practice. Results showed that the presence of pressure-bearing water and explosive cartridges in the drill are the main influence factors of the blasting effect of cement test block. The high load-transmitting performance of pore water and energy accumulation in explosive cartridges were analyzed. Noxious substances produced during the blasting process were properly controlled because of the moistening, cooling, and diluting effect of pore water. Not only the goal of safe and static rock fragmentation by high-explosive detonation but also a combination of superdynamic blast loading and static loading effect of the pressured water was achieved. Then the practice of blasting control of hard coal rocks in Datong coal mine was analyzed to determine reasonable parameters of pressured water coupling blasting. A good presplitting blasting control effect was achieved for the hard coal rocks.

  2. Assessment of Blasting Operations Effects During Highway Tunnel Construction

    Directory of Open Access Journals (Sweden)

    Valašková Veronika

    2015-12-01

    Full Text Available Blasting operations are one of the fundamental parts of daily civil engineering. Drilling and blasting still remain the only possible ways of tunnelling in very adverse geological conditions. However, this method is a source of various disadvantages, the main one being tremors propagating through the geological environment which not only affect buildings, but also disturb the comfort of living in the vicinity of the source. Designing this procedure is mostly done using standardized empirical relations. This article shows the possibility of using a FEM technique in predicting blast effects. This approach is demonstrated in a simple case study on the impact of blasting operations on steel pipes.

  3. Collapse of rocks by blasting. Razrusheniye gornykh porod Vzryvom

    Energy Technology Data Exchange (ETDEWEB)

    Sukhanov, A F; Kutuzov, B N

    1983-01-01

    Information is provided about drilling boreholes and wells, explosives and the means for initiating them, storage, transporting and calculation of the explosive materials. Physical essence of the destructive, scientific and air effect of the blast are presented, principles of arrangement and calculation of the charges, reasons for malfunctions and methods of eliminating them, measures for protecting the surrounding objects from harmful effect of the industrial blast. Questions are examined of planning, organization and safety of the blasting operations. The second edition (first edition 1967) has been revised with regard for changes that occurred in the field of blasting operations.

  4. Water-Depth-Based Prediction Formula for the Blasting Vibration Velocity of Lighthouse Caused by Underwater Drilling Blasting

    Directory of Open Access Journals (Sweden)

    Wenbin Gu

    2017-01-01

    Full Text Available Lighthouses are the most important hydraulic structures that should be protected during underwater drilling blasting. Thus, the effect of blasting vibration on lighthouse should be studied. On the basis of the dimensional analysis, we deduced a revised formula for water depth based on Sodev’s empirical formula and established the linear fitting model. During the underwater reef project in the main channel of Shipu Harbor in the Ningbo–Zhoushan Port, the blasting vibration data of the lighthouse near the underwater blasting area were monitored. The undetermined coefficient, resolvable coefficient, and F value of the two formulas were then obtained. The comparison of the data obtained from the two formulas showed that they can effectively predict the blasting vibration on the lighthouse. The correction formula that considers water depth can obviously reduce prediction errors and accurately predict blasting vibration.

  5. Blast Injuries: What Clinicians Need to Know

    Centers for Disease Control (CDC) Podcasts

    2008-11-05

    In this podcast, Dr. Richard C. Hunt, Director of the CDC’s Division of Injury Response, National Center for Injury Prevention and Control provides a brief overview for health care providers on how to respond and care for persons injured by an explosion or blast event.  Created: 11/5/2008 by National Center for Injury Prevention and Control (NCIPC), Division of Injury Response (DIR).   Date Released: 11/6/2008.

  6. Prevention of Blast-Related Injuries

    Science.gov (United States)

    2017-09-01

    in a canvas harness. The harness was further supported by a steel frame which was suspended from a metal beam (3.7 m off the ground) mounted on...direction of the wave propagation (Figure 5). After proper alignment of the head with respect to the center of the C4 charge, the steel frame was...further tied to four hooks cemented to the concrete ground with straps to prevent excessive motion during the blast exposure. The intensity of the two

  7. Blast vibration monitoring, July to December, 1983

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    The complexity of the vibration waveforms produced appears at this stage to preclude simple comparison of different blasts. A modelling approach is indicated from the preliminary experiments. The required elemental charge length and the steady state column length of ANFO in 381 mm holes must be determined for further development of a model. This information may be acquired by firing a number of charges of varying lengths with all other variables held constant.

  8. Centrifugal shot blasting. Innovative technology summary report

    International Nuclear Information System (INIS)

    1999-07-01

    At the US Department of Energy (DOE) Fernald Environmental Management Project (FEMP), the Facilities Closure and Demolition Projects Integrated Remedial Design/Remedial Action (RD/RA) work plan calls for the removal of one inch (1 in) depth of concrete surface in areas where contamination with technetium-99 has been identified. This report describes a comparative demonstration between two concrete removal technologies: an innovative system using Centrifugal Shot Blasting (CSB) and a modified baseline technology called a rotary drum planer

  9. Running vacuum cosmological models: linear scalar perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Perico, E.L.D. [Instituto de Física, Universidade de São Paulo, Rua do Matão 1371, CEP 05508-090, São Paulo, SP (Brazil); Tamayo, D.A., E-mail: elduartep@usp.br, E-mail: tamayo@if.usp.br [Departamento de Astronomia, Universidade de São Paulo, Rua do Matão 1226, CEP 05508-900, São Paulo, SP (Brazil)

    2017-08-01

    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 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 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.

  10. Blast furnace hearth lining: post mortem analysis

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-05-15

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

  11. Blast furnace hearth lining: post mortem analysis

    International Nuclear Information System (INIS)

    Almeida, Bruno Vidal de; Vernilli Junior, Fernando

    2017-01-01

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

  12. The Blast Fungus Decoded: Genomes in Flux

    Directory of Open Access Journals (Sweden)

    Thorsten Langner

    2018-04-01

    Full Text Available Plant disease outbreaks caused by fungi are a chronic threat to global food security. A prime case is blast disease, which is caused by the ascomycete fungus Magnaporthe oryzae (syn. Pyricularia oryzae, which is infamous as the most destructive disease of the staple crop rice. However, despite its Linnaean binomial name, M. oryzae is a multihost pathogen that infects more than 50 species of grasses. A timely study by P. Gladieux and colleagues (mBio 9:e01219-17, 2018, https://doi.org/10.1128/mBio.01219-17 reports the most extensive population genomic analysis of the blast fungus thus far. M. oryzae consists of an assemblage of differentiated lineages that tend to be associated with particular host genera. Nonetheless, there is clear evidence of gene flow between lineages consistent with maintaining M. oryzae as a single species. Here, we discuss these findings with an emphasis on the ecologic and genetic mechanisms underpinning gene flow. This work also bears practical implications for diagnostics, surveillance, and management of blast diseases.

  13. D-BLAST OFDM with Channel Estimation

    Directory of Open Access Journals (Sweden)

    Du Jianxuan

    2004-01-01

    Full Text Available Multiple-input and multiple-output (MIMO systems formed by multiple transmit and receive antennas can improve performance and increase capacity of wireless communication systems. Diagonal Bell Laboratories Layered Space-Time (D-BLAST structure offers a low-complexity solution for realizing the attractive capacity of MIMO systems. However, for broadband wireless communications, channel is frequency-selective and orthogonal frequency division multiplexing (OFDM has to be used with MIMO techniques to reduce system complexity. In this paper, we investigate D-BLAST for MIMO-OFDM systems. We develop a layerwise channel estimation algorithm which is robust to channel variation by exploiting the characteristic of the D-BLAST structure. Further improvement is made by subspace tracking to considerably reduce the error floor. Simulation results show that the layerwise estimators require 1 dB less signal-to-noise ratio (SNR than the traditional blockwise estimator for a word error rate (WER of when Doppler frequency is 40 Hz. Among the layerwise estimators, the subspace-tracking estimator provides a 0.8 dB gain for WER with 200 Hz Doppler frequency compared with the DFT-based estimator.

  14. The Blast Fungus Decoded: Genomes in Flux.

    Science.gov (United States)

    Langner, Thorsten; Białas, Aleksandra; Kamoun, Sophien

    2018-04-17

    Plant disease outbreaks caused by fungi are a chronic threat to global food security. A prime case is blast disease, which is caused by the ascomycete fungus Magnaporthe oryzae (syn. Pyricularia oryzae ), which is infamous as the most destructive disease of the staple crop rice. However, despite its Linnaean binomial name, M. oryzae is a multihost pathogen that infects more than 50 species of grasses. A timely study by P. Gladieux and colleagues (mBio 9:e01219-17, 2018, https://doi.org/10.1128/mBio.01219-17) reports the most extensive population genomic analysis of the blast fungus thus far. M. oryzae consists of an assemblage of differentiated lineages that tend to be associated with particular host genera. Nonetheless, there is clear evidence of gene flow between lineages consistent with maintaining M. oryzae as a single species. Here, we discuss these findings with an emphasis on the ecologic and genetic mechanisms underpinning gene flow. This work also bears practical implications for diagnostics, surveillance, and management of blast diseases. Copyright © 2018 Langner et al.

  15. Verification of wet blasting decontamination technology

    International Nuclear Information System (INIS)

    Matsubara, Sachito; Murayama, Kazunari; Yoshida, Hirohisa; Igei, Shigemitsu; Izumida, Tatsuo

    2013-01-01

    Macoho Co., Ltd. participated in the projects of 'Decontamination Verification Test FY 2011 by the Ministry of the Environment' and 'Decontamination Verification Test FY 2011 by the Cabinet Office.' And we tested verification to use a wet blasting technology for decontamination of rubble and roads contaminated by the accident of Fukushima Daiichi Nuclear Power Plant of the Tokyo Electric Power Company. As a results of the verification test, the wet blasting decontamination technology showed that a decontamination rate became 60-80% for concrete paving, interlocking, dense-grated asphalt pavement when applied to the decontamination of the road. When it was applied to rubble decontamination, a decontamination rate was 50-60% for gravel and approximately 90% for concrete and wood. It was thought that Cs-134 and Cs-137 attached to the fine sludge scraped off from a decontamination object and the sludge was found to be separated from abrasives by wet cyclene classification: the activity concentration of the abrasives is 1/30 or less than the sludge. The result shows that the abrasives can be reused without problems when the wet blasting decontamination technology is used. (author)

  16. Vacuum Chambers for LEP sections

    CERN Multimedia

    1983-01-01

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

  17. Machine for extrusion under vacuum

    International Nuclear Information System (INIS)

    Gautier, A.

    1958-01-01

    In a study of the behaviour of easily oxidised metals during the extrusion process, it is first necessary to find an effective mean of fighting corrosion, since this, even when barely detectable, has an important influence on the validity of the results recorded. The neatest and also the most efficient of all the methods tried consists in creating a vacuum around the test piece. Working on this principle, and at the same time respecting the conventional rules for extrusion tests (loading the sample after stabilisation at the testing temperature, differential measurements of lengthening, etc.) we found it necessary to construct an original machine. (author) [fr

  18. Entanglement in the Bogoliubov vacuum

    DEFF Research Database (Denmark)

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

    2005-01-01

    We analyze the entanglement properties of the Bogoliubov vacuum, which is obtained as a second-order approximation to the ground state of an interacting Bose-Einstein condensate. We work in one- and two-dimensional lattices and study the entanglement between two groups of sites as a function...... of the geometry of the configuration and the strength of the interactions. As our measure of entanglement we use the logarithmic negativity, supplemented by an algorithmic check for bound entanglement where appropiate. The short-range entanglement is found to grow approximately linearly with the group sizes...

  19. Water-Depth-Based Prediction Formula for the Blasting Vibration Velocity of Lighthouse Caused by Underwater Drilling Blasting

    OpenAIRE

    Gu, Wenbin; Wang, Zhenxiong; Liu, Jianqing; Xu, Jinglin; Liu, Xin; Cao, Tao

    2017-01-01

    Lighthouses are the most important hydraulic structures that should be protected during underwater drilling blasting. Thus, the effect of blasting vibration on lighthouse should be studied. On the basis of the dimensional analysis, we deduced a revised formula for water depth based on Sodev’s empirical formula and established the linear fitting model. During the underwater reef project in the main channel of Shipu Harbor in the Ningbo–Zhoushan Port, the blasting vibration data of the lighthou...

  20. Numerical Investigation of Structural Response of Corrugated Blast Wall Depending on Blast Load Pulse Shapes

    Directory of Open Access Journals (Sweden)

    Jung Min Sohn

    Full Text Available Abstract Hydrocarbon explosions are one of most hazardous events for workers on offshore platforms. To protect structures against explosion loads, corrugated blast walls are typically installed. However, the profiles of real explosion loads are quite different depending on the congestion and confinement of Topside structures. As the level of congestion and confinement increases, the explosion load increases by up to 8 bar, and the rising time of the load decreases. This study primarily aims to investigate the structural behavior characteristics of corrugated blast walls under different types of explosion loadings. Four loading shapes were applied in the structural response analysis, which utilized a dynamic nonlinear finite element method.

  1. Evaluation of Blast Resistance of Fiber Reinforced Composite Specimens under Contact Blast Load

    Science.gov (United States)

    Janota, O.; Foglar, M.

    2017-09-01

    This paper presents results of experimental programme which took place in 2014, 2015 and 2016. Experiments were focused on the resistance of full scale concrete panels subjected to contact blast loading. Specimens were loaded by contact blast by plastic explosive. All specimens were reinforced concrete slabs made of fiber concrete. Basalt mesh and textile sheets were added to some of the experiments for creating more heterogeneous material to achieve better resistance of the specimens. Evaluation of experiments was mainly focused on the damaged area on the contact side and soffit of the specimens. Dependency of the final damage of concrete panels on the weight of explosive and concrete strength was assessed.

  2. Breeding for blast-disease-resistant and high-yield Thai jasmine rice (Oryza sativa L. cv. KDML 105) mutants using low-energy ion beams

    Science.gov (United States)

    Mahadtanapuk, S.; Teraarusiri, W.; Phanchaisri, B.; Yu, L. D.; Anuntalabhochai, S.

    2013-07-01

    Low-energy ion beam was applied on mutation induction for plant breeding of blast-disease-resistant Thai jasmine rice (Oryza sativa L. cv. KDML 105). Seeds of the wild-type rice were bombarded in vacuum by nitrogen ion beam at energy of 60-80 keV to a beam fluence range of 2 × 1016-2 × 1017 ions/cm2. The ion-bombarded rice seeds were grown in soil for 2 weeks as transplanted rice in plastic pots at 1 seedling/pot. The seedlings were then screened for blast resistance by Pyricularia grisea inoculation with 106 spores/ml concentrations. The blast-resistant rice mutant was planted up to F6 generation with the consistent phenotypic variation. The high percentage of the blast-disease-resistant rice was analyzed with DNA fingerprint. The HAT-RAPD (high annealing temperature-random amplified polymorphic DNA) marker revealed the modified polymorphism fragment presenting in the mutant compared with wild type (KDML 105). The cDNA fingerprints were investigated and the polymorphism fragment was subcloned into pGEM-T easy vector and then sequenced. The sequence of this fragment was compared with those already contained in the database, and the fragment was found to be related to the Spotted leaf protein 11 (Spl11).

  3. Vacuum systems for the ILC helical undulator

    CERN Document Server

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

    2007-01-01

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

  4. Straw detector: 1 - Vacuum: 0

    CERN Multimedia

    Katarina Anthony

    2012-01-01

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

  5. High-vacuum plasma pump

    International Nuclear Information System (INIS)

    Dorodnov, A.M.; Minajchev, V.E.; Miroshkin, S.I.

    1980-01-01

    The action of an electric-arc high-vacuum pump intended for evacuating the volumes in which the operation processes are followed by a high gas evolution is considered. The operation of the pump is based on the principle of controlling the getter feed according to the gas load and effect of plasma sorbtion pumping. The pump performances are given. The starting pressure is about 5 Pa, the limiting residual pressure is about 5x10 -6 Pa, the pumping out rate of nitrogen in the pressure range 5x10 -5 -5x10 -3 Pa accounts for about 4000 l/s, the power consumption comes to 6 kW. Analyzing the results of the test operation of the pump, it has been concluded that its principal advantages are the high starting pressure, controlled getter feed rate and possibility of pumping out the gases which are usually pumped out with difficulty. The operation reliability of the pump is defined mainly by reliable operation of the ignition system of the vacuum arc [ru

  6. The JET vacuum interspace system

    International Nuclear Information System (INIS)

    Orchard, J.; Scales, S.

    1999-01-01

    In the past JET has suffered from a number of vacuum leaks on components such as bellows, windows and feedthroughs due, in part, to the adverse conditions, including high mechanical forces, which may prevail during plasma operation. Therefore before the recent Tritium experiments on JET it was deemed prudent to manufacture and install items with a secondary containment or interspace in order to minimise the effect of failure of the primary vacuum barrier on both the leak integrity of the machine and the outcome of the experiments. This paper describes the philosophy, logistics, method and implementation of an integrated connection and monitoring system on the 330 interspaces currently in position on the JET machine. Using the JET leak database comparisons are drawn of leak failure rates of the components allied to the number of operational hours, prior to the system being present and after installation and commissioning, and the case of detection compared to the previous situation. An argument is also presented on the feasibility and adaptability of this system to any large complex machine and the benefits to be obtained in reduction of leaks and operational down time. (author)

  7. Gases vacuum dedusting and cooling

    Directory of Open Access Journals (Sweden)

    Alexey А. Burov

    2015-03-01

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

  8. Advanced Photon Source accelerator ultrahigh vacuum guide

    International Nuclear Information System (INIS)

    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

  9. TORE SUPRA vacuum vessel and shield manufacturing

    International Nuclear Information System (INIS)

    Blateyron, J.; Lepez, R.

    1984-01-01

    TORE SUPRA vacuum vessel and vacuum chamber shield manufacturing in progress at Jeumont-Schneider consists of three main phases: - Detail engineering and manufacturing fixture construction; - Prototype section manufacturing and process preparation; - Construction of the 6 production modules. The welding techniques adopted, call for three special automatic processes: TIG, MIG and PLASMA welding which guarantee mechanical strength, vacuum tightness and absence of distortion. Production of the modules began July 1984. (author)

  10. Vacuum technology in the chemical industry

    CERN Document Server

    Jorisch, Wolfgang

    2015-01-01

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

  11. Development of a vacuum superinsulation panel

    Energy Technology Data Exchange (ETDEWEB)

    Timm, H; Seefeldt, D; Nitze, C

    1983-05-01

    After completion of the investigations the vacuum-insulated panel is available as prototype. The aim of the investigations was to optimize and to finalize the vacuum superinsulation system with regard to a pressure-resistant, temperature-resistant thermal insulation of high efficiency. In this connection, particularly investigations with regard to vacuum-tight sealing, compression and evacuation of powder filling as well as special material investigations were performed. The application-specific utilization of the vacuum-insulated panel and the adjustment to special operational conditions can now be started. Application possibilities are at present seen in coverings or linings with high temperature and/or pressure requirements.

  12. Dynamical effects of QCD vacuum structure

    International Nuclear Information System (INIS)

    Ferreira, Erasmo

    1994-01-01

    The role of the QCD vacuum structure in the determination of the properties of states and processes occurring in the confinement regime of QCD is reviewed. The finite range of the vacuum correlations is discussed, and an analytical form is suggested for the correlation functions. The role of the vacuum quantum numbers in the phenomenology of high-energy scattering is reviewed. The vacuum correlation model of non-perturbative QCD is mentioned as a bridge between the fundamental theory and the description of the experiments. (author). 13 refs., 1 fig

  13. Cold vacuum drying facility design requirements

    International Nuclear Information System (INIS)

    IRWIN, J.J.

    1999-01-01

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

  14. Vacuum exhaust duct used for thermonuclear device

    International Nuclear Information System (INIS)

    Tachikawa, Nobuo; Kondo, Mitsuaki; Honda, Tsutomu.

    1990-01-01

    The present invention concerns a vacuum exhaust duct used for a thermonuclear device. A cylindrical metal liners is lined with a gap to the inside of a vacuum exhaust duct main body. Bellows are connected to both ends of the metal liners and the end of the bellows is welded to the vacuum exhaust duct main body. Futher, a heater is mounted to the metal liner on the side of the vacuum exhaust duct main body, and the metal liner is heated by the heater to conduct baking for the vacuum exhaust duct main body. Accordingly, since there is no requirement for elevating the temperature of the vacuum exhaust duct upon conducting baking, the vacuum exhaust duct scarcely suffers substantial deformation due to heat expansion. Further, there is also no substantial deformation for the bellows disposed between the outer circumference of the vacuum vessel and a portion of a vacuum exhaust duct, so that the durability of the bellows is greatly improved. (I.S.)

  15. Evacuation of the NET vacuum chamber

    International Nuclear Information System (INIS)

    Muller, R.A.

    1987-01-01

    Parametric calculations of the evacuation process were carried out for the NET-vacuum chamber involving two blanket designs. The results show that with an acceptable vacuum pumping capacity the required start vacuum conditions can be realized within reasonable time. The two blanket concepts do not differ remarkably in their evacuation behaviour. The remaining large pressure differences between the different locations of the vacuum chamber can be reduced if approximately 30% of the total gas flow is extracted from the heads of the blanket replacement ports

  16. Evacuation of the NET vacuum chamber

    International Nuclear Information System (INIS)

    Mueller, R.

    1986-01-01

    Parametric calculations of the evacuation process were carried out for the NET-vacuum chamber involving two blanket designs. The results show that with an acceptable vacuum pumping capacity the required start vacuum conditions can be realized within reasonable time. The two blanket concepts do not differ remarkably in their evacuation behaviour. The remaining large pressure differences between the different locations of the vacuum chamber can be reduced if approximately 30% of the total gas flow is extracted from the heads of the blanket replacement ports. (author)

  17. Cold vacuum drying facility design requirements

    Energy Technology Data Exchange (ETDEWEB)

    IRWIN, J.J.

    1999-07-01

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

  18. 30 CFR 57.6605 - Isolation of blasting circuits.

    Science.gov (United States)

    2010-07-01

    ... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Extraneous Electricity-Surface and Underground § 57.6605 Isolation of blasting circuits. Lead wires and blasting lines shall be isolated and insulated from power conductors, pipelines, and railroad tracks, and...

  19. Blasting Standards for the Ghanaian Mining Industry | Amegbey ...

    African Journals Online (AJOL)

    Ghana is a well known mining nation and hard rock mining has been going on since the 10th century. Mining companies in Ghana are well aware of the regulatory requirements to carry out blasting activities such that neighbouring communities are protected from excessive impact as a result of blast vibrations amongst other ...

  20. Liquid flow in the hearth of the blast furnace

    International Nuclear Information System (INIS)

    Gauje, P.; Nicolle, R.; Steiler, J.M.; Venturini, M.J.; Libralesso, J.M.

    1992-01-01

    The hearth of a blast furnace is poorly known. Our approach to characterize the hearth involves classical methods of chemical engineering, assessing the flow conditions by means of radioactive tracer techniques. The most important feature of this study is to combine measurements on industrial blast furnaces, experiments on a small scale model and flow model. calculations. 8 refs., 16 figs

  1. Implementation of a user defined mine blast model in LSDYNA

    NARCIS (Netherlands)

    Tyler-Street, M.; Leerdam, P.J.C.

    2012-01-01

    A user defined mine blast model has been developed and implemented into the explicit finite element code LS-DYNA to provide a numerically efficient method for simulating an antivehicular mine blast. The objective is to provide a simple and robust numerical method which is able to represent both the

  2. Inheritance of blast resistance and identification of SSR marker ...

    Indian Academy of Sciences (India)

    2013-08-02

    Aug 2, 2013 ... arm of chromosome 6 and in close proximity of blast resis- ... resistance to a M. oryzae race in a gene-for-gene manner. DNA markers have been ... order to identify the new sources of resistance against blast, there is need for ...

  3. 30 CFR 75.1310 - Explosives and blasting equipment.

    Science.gov (United States)

    2010-07-01

    ... for use so long as the present approval is maintained. (e) Electric detonators shall be compatible... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosives and blasting equipment. 75.1310... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1310...

  4. Equipment Specific Optimum Blast-Design Using Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Rahul Upadhyay

    2015-08-01

    Full Text Available Design of blasting parameters plays an important role in the optimization of mining cost as well as cost of subsequent processing of ore. Drilling and handling costs are the major mining cost. This work presents an indirect optimization model for mining cost through optimization of blasting parameters for a particular set of drilling and loading equipment.

  5. Storage stability of flour-blasted brown rice

    Science.gov (United States)

    Brown rice was blasted with rice flour rather than sand in a sand blaster to make microscopic nicks and cuts so that water can easily penetrate into the brown rice endosperm and cook the rice in a shorter time. The flour-blasted American Basmati brown rice, long grain brown rice, and parboiled long...

  6. Advanced light source vacuum policy and vacuum guidelines for beamlines and experiment endstations

    International Nuclear Information System (INIS)

    Hussain, Z.

    1995-08-01

    The purpose of this document is to: (1) Explain the ALS vacuum policy and specifications for beamlines and experiment endstations. (2) Provide guidelines related to ALS vacuum policy to assist in designing beamlines which are in accordance with ALS vacuum policy. This document supersedes LSBL-116. The Advanced Light Source is a third generation synchrotron radiation source whose beam lifetime depends on the quality of the vacuum in the storage ring and the connecting beamlines. The storage ring and most of the beamlines share a common vacuum and are operated under ultra-high-vacuum (UHV) conditions. All endstations and beamline equipment must be operated so as to avoid contamination of beamline components, and must include proper safeguards to protect the storage ring vacuum from an accidental break in the beamline or endstation vacuum systems. The primary gas load during operation is due to thermal desorption and electron/photon induced desorption of contaminants from the interior of the vacuum vessel and its components. The desorption rates are considerably higher for hydrocarbon contamination, thus considerable emphasis is placed on eliminating these sources of contaminants. All vacuum components in a beamline and endstation must meet the ALS vacuum specifications. The vacuum design of both beamlines and endstations must be approved by the ALS Beamline Review Committee (BRC) before vacuum connections to the storage ring are made. The vacuum design is first checked during the Beamline Design Review (BDR) held before construction of the beamline equipment begins. Any deviation from the ALS vacuum specifications must be approved by the BRC prior to installation of the equipment on the ALS floor. Any modification that is incorporated into a vacuum assembly without the written approval of the BRC is done at the user's risk and may lead to rejection of the whole assembly

  7. Reducing Drill and Blast Cost through Blast Optimisation – A Case ...

    African Journals Online (AJOL)

    Michael O. Mensah

    2015-12-02

    Dec 2, 2015 ... Case Study* ... using the proposed blast parameters increased by 14.3 to 50.0% for ore zones and 12.5 ... of gold, compels technologists in the industry to .... 127. Bench Height (H), m. 4. 4. 4.5. 4.5. 4.5. 4.5. Sub-drill (U), m. 0.5.

  8. Evaluating the Effectiveness of Various Blast Loading Descriptors as Occupant Injury Predictors for Underbody Blast Events

    Science.gov (United States)

    2013-08-22

    expressed herein do not necessarily state or reflect those of the United States Government or the DoD, and shall not be used for advertising or...Trembelay, J., “Validation of a Loading Model for Simulating Blast Mine Effects on Armoured Vehicles,” 7th International LS-DYNA Users Conference

  9. Blasting and Blast Effects in Cold Regions. Part 3. Explosions in Ground Materials

    Science.gov (United States)

    1989-05-01

    121- York, Ontario: Technical Marketing Services- 123. Explosives, Canadian Industries, 6th edition. Gaffney, E.S. (1984b) Hugoniot of water ice. In...Mines, blasting. U.S. Bureau of Nlines , Report of Insesti- Report of lnsestigations RI 7751. gations 8507. Piekutoiski. A.J. (1974) I.aborator,, scale

  10. Fusion reactor high vacuum pumping

    International Nuclear Information System (INIS)

    Sedgley, D.W.; Walthers, C.R.; Jenkins, E.M.

    1992-01-01

    This paper reports on recent experiments which have shown the practicality of using activated carbon (coconut charcoal) at 4K to pump helium and hydrogen isotopes for a fusion reactor. Both speed and capacity for deuterium/helium and tritium/helium-3 mixtures were satisfactory. The long-term effects of tritium on the charcoal/cement system developed by Grumman and LLNL was now known; therefore a program was undertaken to see what, if any, effect long-term tritium exposure has on the cryosorber. Several charcoal on aluminum test samples were subjected to six months exposure of tritium at approximately 77 K. The tritium was scanned several times with a residual gas analyzer and the speed-capacity performance of the samples was measured before, approximately one-third way through, and after the exposure. Modest effects were noted which would not seriously restrict the use of charcoal as a cryosorber for fusion reactor high-vacuum pumping applications

  11. Effect of Surface Blasting on Subway Tunnels- A Parametric Study

    Directory of Open Access Journals (Sweden)

    Hossein Entezari Zarch

    2017-01-01

    Full Text Available During wars and crises, the underground tunnels are used as a safe space. Therefore, the stability and safety of them under a blast is of particular importance. In this paper, the Finite Difference Method has been used to study the influence of the change in geotechnical parameters and depth on surface blasting on subway tunnels. Results showed that increasing the internal friction angle, modulus of elasticity and cohesion of the soil reduced the effects of blast loads on the vertical displacement and bending moment in the center of tunnel crown. Furthermore, the results showed that increasing the depth of the tunnel reduced the effects of blast loading. Comparing all parameters collectively showed that the increase in the modulus of elasticity of the soil and depth of the tunnel is the most effective in reducing the influence of the blast loads on the vertical displacement and bending moment of the tunnel crown, respectively.

  12. Confirmation of the decontamination ability using the dry blasting device

    International Nuclear Information System (INIS)

    Izuka, Hirotaka; Tsuhara, Yuuki; Ito, Hajime; Fukuda, Kazuhiro; Sugahara, Yasuhiro; Kanamori, Yoji

    2017-01-01

    The decontamination method of metallic waste was considered to reduce the radioactive waste in decommissioning a nuclear power plant. Stainless steel occupies most for the material of the system equipment of PWR. The contamination by radioactive materials is stuck in the surface in the equipment as the metal oxide (e.g. chromium oxide, iron oxide). The method of efficient abrasion by the dry blasting device was considered to remove metal oxide from stainless steel. The kind of blasting abrasives material and the abrasive operation condition (the blasting angle, rate) were considered to investigate the abrasion ability to stainless steel. The abrasive condition which was appropriate abrasive ability was investigated and appropriate blasting abrasives was selected to stainless steel. The decontamination test by selected blasting abrasives and abrasive operation condition was performed using samples and the relation between abrasive rate and activity concentration was confirmed. The metallic radioactive waste was confirmed to be able to decontaminate to the clearance level. (author)

  13. Progress of ITER vacuum vessel

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-10-15

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

  14. The physics of ''vacuum'' breakdown

    International Nuclear Information System (INIS)

    Schwirzke, F.

    1993-01-01

    Many discharges form small cathode spots which provide such a high energy density that the cathode material explodes into a dense plasma cloud within a very short time. Despite the fundamental importance of cathode spots for the breakdown process and the formation of a discharge, the structure of the cathode spot plasma and the source of the high energy density were not yet well defined. One model, the whisker explosive emission model, assumes that joule heating by field emitted electrons provides the energy. Current densities of j FE = 10 12 - 10 13 A/m 2 would be required. However, the pre-breakdown j FE is self-limiting. The negative space charge caused by j FE in the cathode-anode gap reduces the effective electric field E on the cathode surface. The maximum current density j CL is space charge limited by Child-Langmuir's law. The field emitting spot cannot deliver j CL without turning itself off, since the negative space charge caused by j CL reduces E congruent 0 at the cathode surface. Hence, it must be that the vacuum j FE CL . The development of a current with j > j FE (vacuum) requires that ions exist in front of the electron emitting spot. Ions cannot be emitted from the surface of the field emitting spot, the enhanced electric field would hold them back. The initial ionization must occur in the cathode-anode gap near the electron emitting spot. Ionization of desorbed neutrals provides the mechanism. This ionization process requires considerably less current than the ionization of solid material by joule heating. Field emission and the impact of ions stimulate desorption of weakly bound adsorbates from the surface of the electron emitting spot. The cross section for ionization of the neutrals has a maximum for ∼ 100 eV electrons

  15. Vacuum ultraviolet photochemistry of polymers

    International Nuclear Information System (INIS)

    Skurat, Vladimir

    2003-01-01

    The interaction of vacuum UV radiation (wavelength range from 1 to 200 nm) with polymers is interesting for fundamental and applied sciences. This interest is stimulated by various reasons: - Wide applications of polymeric materials in semiconductor technology, where they are used as photoresist materials in combination with VUV light sources (lasers, excimer lamps, synchrotron radiation and others). - Polymers are widely used as spacecraft materials in the last 20 years. On near-Earth orbits, the polymeric materials of spacecraft surfaces are destroyed by solar radiation. - VUV radiation is one of the components of gas discharge plasmas, which are used for treatment of polymer, with the aim of modifying their surface properties. The main features of interaction of VUV radiation with polymers are discussed. The spectra of intrinsic absorption of saturated polymers (polyethylene, polypropylene, polytetrafluoroethylene and others) are situated mainly in the VUV region. The photochemistry of polymers in the VUV region is very different from their photochemistry at wavelengths longer than 200 nm, where the absorption spectra belong to impurities and polymer defects. The polymer photochemistry in the VUV region is wavelength-dependent. At wavelengths longer than about 140 nm, the main role is played by transformations of primary-formed singlet excited molecules. At shorter wavelengths the role of photoionization increases progressively and the main features of VUV photolysis become similar to the picture of radiolysis, with significant contributions of charge pairs and triplet excited molecules. Very important features of VUV light absorption in polymers are high absorption coefficients. Because of this, the surface layers absorb large doses of energy. This leads to very profound transformation of material on the polymer surface. In particular for polymers which are considered destroyed by radiation (for example, perfluoropolymers), this leads to VUV-induced erosion

  16. Progress of ITER vacuum vessel

    International Nuclear Information System (INIS)

    Ioki, K.; Bayon, A.; Choi, C.H.; Daly, E.; Dani, S.; Davis, J.; Giraud, B.; Gribov, Y.; Hamlyn-Harris, C.; Jun, C.; Levesy, B.; Kim, B.C.; Kuzmin, E.; Le Barbier, R.; Martinez, J.-M.; Pathak, H.; Preble, J.; Sa, J.W.; Terasawa, A.; Utin, Yu.

    2013-01-01

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

  17. Attenuation of blast pressure behind ballistic protective vests.

    Science.gov (United States)

    Wood, Garrett W; Panzer, Matthew B; Shridharani, Jay K; Matthews, Kyle A; Capehart, Bruce P; Myers, Barry S; Bass, Cameron R

    2013-02-01

    Clinical studies increasingly report brain injury and not pulmonary injury following blast exposures, despite the increased frequency of exposure to explosive devices. The goal of this study was to determine the effect of personal body armour use on the potential for primary blast injury and to determine the risk of brain and pulmonary injury following a blast and its impact on the clinical care of patients with a history of blast exposure. A shock tube was used to generate blast overpressures on soft ballistic protective vests (NIJ Level-2) and hard protective vests (NIJ Level-4) while overpressure was recorded behind the vest. Both types of vest were found to significantly decrease pulmonary injury risk following a blast for a wide range of conditions. At the highest tested blast overpressure, the soft vest decreased the behind armour overpressure by a factor of 14.2, and the hard vest decreased behind armour overpressure by a factor of 56.8. Addition of body armour increased the 50th percentile pulmonary death tolerance of both vests to higher levels than the 50th percentile for brain injury. These results suggest that ballistic protective body armour vests, especially hard body armour plates, provide substantial chest protection in primary blasts and explain the increased frequency of head injuries, without the presence of pulmonary injuries, in protected subjects reporting a history of blast exposure. These results suggest increased clinical suspicion for mild to severe brain injury is warranted in persons wearing body armour exposed to a blast with or without pulmonary injury.

  18. Survey of rice blast race identity for blast resistance gene identification in the USA and Puerto Rico

    Science.gov (United States)

    Rice blast disease is a significant threat to stable rice production in the USA and worldwide. The major resistance gene (Pi-ta) located within a cluster of resistance genes on rice chromosome 12 has been demonstrated to confer resistance to the rice blast disease. Katy, a rice cultivar released in ...

  19. Experimental investigation of blast mitigation and particle-blast interaction during the explosive dispersal of particles and liquids

    Science.gov (United States)

    Pontalier, Q.; Loiseau, J.; Goroshin, S.; Frost, D. L.

    2018-05-01

    The attenuation of a blast wave from a high-explosive charge surrounded by a layer of inert material is investigated experimentally in a spherical geometry for a wide range of materials. The blast wave pressure is inferred from extracting the blast wave velocity with high-speed video as well as direct measurements with pressure transducers. The mitigant consists of either a packed bed of particles, a particle bed saturated with water, or a homogeneous liquid. The reduction in peak blast wave overpressure is primarily dependent on the mitigant to explosive mass ratio, M/ C, with the mitigant material properties playing a secondary role. Relative peak pressure mitigation reduces with distance and for low values of M/ C (compaction, deformation, and fracture of the powders plays an important role. The difference in scaled arrival time of the blast and material fronts increases with M/ C and scaled distance, with solid particles giving the largest separation between the blast wave and cloud of particles. Surrounding a high-explosive charge with a layer of particles reduces the positive-phase blast impulse, whereas a liquid layer has no influence on the impulse in the far field. Taking the total impulse due to the blast wave and material impact into account implies that the damage to a nearby structure may actually be augmented for a range of distances. These results should be taken into consideration in the design of explosive mitigant systems.

  20. Proceedings of the seventeenth annual conference on explosives and blasting technique. Volume 2

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Papers from this conference dealt with the following topics: surface and underground mine blasting, ground vibrations and blast effects, design for explosive fracturing of rock, sequential timing for blasting control, design for production optimization, use of blasting for abandoned mine reclamation, chemical explosives, lightning warning systems, magazine security, fire safety, and drilling equipment. Papers have been indexed separately for inclusion on the data base

  1. 22 CFR 121.11 - Military demolition blocks and blasting caps.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Military demolition blocks and blasting caps... blasting caps. Military demolition blocks and blasting caps referred to in Category IV(a) do not include the following articles: (a) Electric squibs. (b) No. 6 and No. 8 blasting caps, including electric...

  2. Vacuum state supersymmetry in d=11 supergravity

    International Nuclear Information System (INIS)

    Vasilevich, D.V.

    1987-01-01

    Supersymmetry of vacuum state in d=11 supergravity is considered. Proceeding on sufficiently general assumptions relatively superformation parameter only Freud-Rubin type solutions may possess supersymmetries. To obtain this result no restrictions on the form of superformation parameter, supealgebra of vacuum global supersymmetry and the form of boson fields were imposed

  3. VACUUM ASSISTED CLOSURE IN DIABETIC FOOT MANAGEMENT

    OpenAIRE

    Moganakannan; `Prema; Arun Sundara Rajan

    2014-01-01

    Comparision of vacuum assisted closure vs conventional dressing in management of diabetic foot patients. 30 patients were taken in that 15 underwent vacuum therapy and remaining 15 underwent conventional dressing.They were analysed by the development of granulation tissue and wound healing.The study showed Vac therapy is the best modality for management of diabetic foot patients.

  4. AA, vacuum tank for stochastic precooling

    CERN Multimedia

    CERN PhotoLab

    1979-01-01

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

  5. Quality Management of CERN Vacuum Controls

    CERN Document Server

    Antoniotti, F; Fortescue-Beck, E; Gama, J; Gomes, P; Le Roux, P; Pereira, H F; Pigny, G

    2014-01-01

    The vacuum controls Section (TE-VSC-ICM) is in charge of the monitoring, maintenance and consolidation of the control systems of all accelerators and detectors in CERN; this represents 6 000 instruments distributed along 128 km of vacuum chambers, often of heterogeneous architectures and of diverse

  6. Silicates materials of high vacuum technology

    CERN Document Server

    Espe, Werner

    2013-01-01

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

  7. The probability of the false vacuum decay

    International Nuclear Information System (INIS)

    Kiselev, V.; Selivanov, K.

    1983-01-01

    The closed expession for the probability of the false vacuum decay in (1+1) dimensions is given. The probability of false vacuum decay is expessed as the product of exponential quasiclassical factor and a functional determinant of the given form. The method for calcutation of this determinant is developed and a complete answer for (1+1) dimensions is given

  8. Rock breaking methods to replace blasting

    Science.gov (United States)

    Zhou, Huisheng; Xie, Xinghua; Feng, Yuqing

    2018-03-01

    The method of breaking rock by blasting has a high efficiency and the cost is relatively low, but the associated vibration, flyrock, production of toxic gases since the 1970’s, the Western developed countries began to study the safety of breaking rock. This paper introduces different methods and their progress to safely break rock. Ideally, safe rock breaking would have little vibration, no fly stone, and no toxic gases, which can be widely used in municipal engineering, road excavation, high-risk mining, quarrying and complex environment.

  9. Explosive and accessories in rock blasting

    Energy Technology Data Exchange (ETDEWEB)

    Pingua, B.M.P.; Nabiullah, M.; Jagdish, S.; Mishra, G.D.; Singh, T.N. [Central Mining Research Institute, Dhanbad (India)

    1999-02-01

    Chemical explosives are commonly used in the mining industry. Those used in India include nitroglycerine (NG) base, ammonium nitrate fuel oil mixture (ANFO), slurry emulsion and liquid oxygen (LOX). Examples of each type and their general properties are lighted. The electric and non-electric detonating systems used are described. Two Indian companies are producing non-electric in-hole delay system. Raydet (IDL-make) and Excel (ICI-make). Their firing characteristics are listed. Tables are given for burden for different density of rock and explosive strength. Causes of bad blast are itemised. 7 refs., 4 figs., 7 tabs.

  10. Reliability of engineered basements as blast shelters

    International Nuclear Information System (INIS)

    Longinow, A.; Mohammadi, J.; Robinson, R.R.

    1983-01-01

    A method for predicting the probability of failure of structures by considering multiple failure modes was formulated. It was applied to the analysis of a reinforced concrete slab when subjected to a uniformly distributed blast load over its surface. Currently available criteria for failure due to flexure and shear were used in predicting the probability of failure. This method is capable of considering all major components of a structure, the respective failure modes of each component, and of predicting the probability of failure of the structure as a whole

  11. Design of blast simulators for nuclear testing

    International Nuclear Information System (INIS)

    Mark, A.; Opalka, K.O.; Kitchens, C.W. Jr.

    1983-01-01

    A quasi-one-dimensional computational technique is used to model the flow of a large, complicated shock tube. The shock tube, or Large Blast Simulator, is used to simulate conventional or nuclear explosions by shaping the pressure history. Results from computations show favorable agreement when compared with data taken in the facility at Gramat, France. Such future shock tubes will include a thermal irradiation capability to better simulate a nuclear event. The computations point to the need for venting of the combustion products since the pressure history will be considerably altered as the shock propagates through these hot gases

  12. Prevention of Blast-Related Injuries

    Science.gov (United States)

    2013-07-01

    influence of cerebrospinal fluid (CSF) on the shock wave response 3. Development of the geometric model for the head of a 23 55-kg Yucatan pig 4...of Tissue-Tek® optimum cutting compound and 20% sucrose (w/v) and frozen in a stream of liquid nitrogen (Saljo et al, 2008). The frozen blocks will...review of current models of the pig head under air blast loading 2. Development of a 2-D pig head FE model to study the influence of cerebrospinal fluid

  13. A new vacuum for loop quantum gravity

    International Nuclear Information System (INIS)

    Dittrich, Bianca; Geiller, Marc

    2015-01-01

    We construct a new vacuum and representation for loop quantum gravity. Because the new vacuum is based on BF theory, it is physical for (2+1)-dimensional gravity, and much closer to the spirit of spin foam quantization in general. To construct this new vacuum and the associated representation of quantum observables, we introduce a modified holonomy–flux algebra that is cylindrically consistent with respect to the notion of refinement by time evolution suggested in Dittrich and Steinhaus (2013 arXiv:1311.7565). This supports the proposal for a construction of the physical vacuum made in Dittrich and Steinhaus (2013 arXiv:1311.7565) and Dittrich (2012 New J. Phys. 14 123004), and for (3+1)-dimensional gravity. We expect that the vacuum introduced here will facilitate the extraction of large scale physics and cosmological predictions from loop quantum gravity. (fast track communication)

  14. Vacuum and ultravacuum physics and technology

    CERN Document Server

    Bello, Igor

    2018-01-01

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

  15. [Ambulant treatment of wounds by vacuum sealing].

    Science.gov (United States)

    Ziegler, U E; Schmidt, K; Breithaupt, B; Menig, R; Debus, E S; Thiede, A

    2000-01-01

    The treatment of chronic wounds by vacuum sealing as an outpatient procedure is a new method of wound conditioning before closing the defect. The quality of life for the patient in his usual surrounding is maintained. Financial aspects also play a role in this treatment since costs for the health care system can be reduced. Various vacuum pumps, drainages and polymere foams are available and suitable for the outpatient treatment. The most important condition is to regularly check the vacuum. This can performed by the patient, the relatives or nursing staff. The main complication consists in loss of vacuum but technical and local or systemic complications can also appear. Individually applied vacuum dressings (polyvinyl foam, drainage tube and polymere foil) are practical. The ideal pump systems for the outpatient treatment are still not trial.

  16. Maxwell electrodynamics subjected to quantum vacuum fluctuations

    International Nuclear Information System (INIS)

    Gevorkyan, A. S.; Gevorkyan, A. A.

    2011-01-01

    The propagation of electromagnetic waves in the vacuum is considered taking into account quantum fluctuations in the limits of Maxwell-Langevin (ML) equations. For a model of “white noise” fluctuations, using ML equations, a second order partial differential equation is found which describes the quantum distribution of virtual particles in vacuum. It is proved that in order to satisfy observed facts, the Lamb Shift etc, the virtual particles should be quantized in unperturbed vacuum. It is shown that the quantized virtual particles in toto (approximately 86 percent) are condensed on the “ground state” energy level. It is proved that the extension of Maxwell electrodynamics with inclusion of the vacuum quantum field fluctuations may be constructed on a 6D space-time continuum with a 2D compactified subspace. Their influence on the refraction indexes of vacuum is studied.

  17. Mechanics and Physics of Precise Vacuum Mechanisms

    CERN Document Server

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

    2010-01-01

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

  18. Approximated calculation of the vacuum wave function and vacuum energy of the LGT with RPA method

    International Nuclear Information System (INIS)

    Hui Ping

    2004-01-01

    The coupled cluster method is improved with the random phase approximation (RPA) to calculate vacuum wave function and vacuum energy of 2 + 1 - D SU(2) lattice gauge theory. In this calculating, the trial wave function composes of single-hollow graphs. The calculated results of vacuum wave functions show very good scaling behaviors at weak coupling region l/g 2 >1.2 from the third order to the sixth order, and the vacuum energy obtained with RPA method is lower than the vacuum energy obtained without RPA method, which means that this method is a more efficient one

  19. Impact of Drill and Blast Excavation on Repository Performance Confirmation

    International Nuclear Information System (INIS)

    Keller, R.; Francis, N.; Houseworth, J.; Kramer, N.

    2000-01-01

    There has been considerable work accomplished internationally examining the effects of drill and blast excavation on rock masses surrounding emplacement openings of proposed nuclear waste repositories. However, there has been limited discussion tying the previous work to performance confirmation models such as those proposed for Yucca Mountain, Nevada. This paper addresses a possible approach to joining the available information on drill and blast excavation and performance confirmation. The method for coupling rock damage data from drill and blast models to performance assessment models for fracture flow requires a correlation representing the functional relationship between the peak particle velocity (PPV) vibration levels and the potential properties that govern water flow rates in the host rock. Fracture aperture and frequency are the rock properties which may be most influenced by drill and blast induced vibration. If it can be shown (using an appropriate blasting model simulation) that the effect of blasting is far removed from the waste package in an emplacement drift, then disturbance to the host rock induced in the process of drill and blast excavation may be reasonably ignored in performance assessment calculations. This paper proposes that the CANMET (Canada Center for Mineral and Energy Technology) Criterion, based on properties that determine rock strength, may be used to define a minimum PPV. This PPV can be used to delineate the extent of blast induced damage. Initial applications have demonstrated that blasting models can successfully be coupled with this criterion to predict blast damage surrounding underground openings. The Exploratory Studies Facility at Yucca Mountain has used a blasting model to generate meaningful estimates of near-field vibration levels and damage envelopes correlating to data collected from pre-existing studies conducted. Further work is underway to expand this application over a statistical distribution of geologic

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

    International Nuclear Information System (INIS)

    Cheng Shaoyong; Xiu Shixin; Wang Jimei; Shen Zhengchao

    2006-01-01

    The greenhouse effect of SF 6 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Kohri, Kazunori [Institute of Particle and Nuclear Studies, KEK, 1-1 Oho, Tsukuba 305-0801 (Japan); Matsui, Hiroki, E-mail: kohri@post.kek.jp, E-mail: matshiro@post.kek.jp [The Graduate University for Advanced Studies (SOKENDAI), 1-1 Oho, Tsukuba 305-0801 (Japan)

    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 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, 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 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} .

  2. Ultra high vacuum systems for accelerators

    International Nuclear Information System (INIS)

    Loefgren, P.

    2001-01-01

    Full text: In order to perform controlled, stable, and reproducible experiments, several research areas today require very low pressures. Maybe the most important example is the research that is performed in storage rings and accelerators where the lifetime and stability of particle beams depends critically on the vacuum conditions. Although the vacuum requirements ultimately depend on the kind of experiments that is performed, the studies of more and more rare and exotic species in storage rings and accelerators today pushes the demands on the vacuum conditions towards lower and lower pressures. The final pressure obtained in the vacuum system can often be the key factor for the outcome of an experiment. Pioneering work in vacuum technology has therefore often been performed at storage rings and accelerator facilities around the world. In order to reach pressures in the low UHV regime and lower (below 10 -11 mbar), several aspects have to be considered which implies choosing the proper materials, pumps and vacuum gauges. In the absence of gases inleaking from the outside, the rate of gas entering a vacuum system is determined by the release of molecules adsorbed on the surfaces and the outgassing from the bulk of the vacuum chamber walls. This means that the choice of material and, equally important, the pre treatment of the material, must be such that these rates are minimised. Today the most widely used material for vacuum applications are stainless steel. Besides its many mechanical advantages, it is resistant to corrosion and oxidation. If treated correctly the major gas source in a stainless steel chamber is hydrogen outgassing from the chamber walls. The hydrogen outgassing can be decreased by vacuum firing at 950 deg. C under vacuum. In addition to choosing the right materials the choice of vacuum pumps is important for the final pressure. Since no vacuum pump is capable of taking care of all kinds of gases found in the rest gas at pressures below 10 -11

  3. Wireless Integrated Microelectronic Vacuum Sensor System

    Science.gov (United States)

    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

  4. Blast-Resistant Improvement of Sandwich Armor Structure with Aluminum Foam Composite

    OpenAIRE

    Yang, Shu; Qi, Chang

    2013-01-01

    Sandwich armor structures with aluminum foam can be utilized to protect a military vehicle from harmful blast load such as a landmine explosion. In this paper, a system-level dynamic finite element model is developed to simulate the blast event and to evaluate the blast-resistant performance of the sandwich armor structure. It is found that a sandwich armor structure with only aluminum foam is capable of mitigating crew injuries under a moderate blast load. However, a severe blast load causes...

  5. Control of City Shallow Buried Tunnel Blasting Hazard to Surface Buildings

    Directory of Open Access Journals (Sweden)

    Yang Deqiang

    2015-01-01

    Full Text Available Combining with the blasting test of an under-construction tunnel, this paper optimizes the overall blasting construction scheme. The optimized blasting scheme is used in the site construction test and the peak particle vibration velocity is strictly controlled under working conditions through blasting vibration monitoring to ensure the safety of surrounding buildings and structures in the construction process. The corresponding control measures are proposed to reduce the blasting vibration which brings certain guiding significance to the following construction project.

  6. Determination of Destress Blasting Effectiveness Using Seismic Source Parameters

    Science.gov (United States)

    Wojtecki, Łukasz; Mendecki, Maciej J.; Zuberek, Wacaław M.

    2017-12-01

    Underground mining of coal seams in the Upper Silesian Coal Basin is currently performed under difficult geological and mining conditions. The mining depth, dislocations (faults and folds) and mining remnants are responsible for rockburst hazard in the highest degree. This hazard can be minimized by using active rockburst prevention, where destress blastings play an important role. Destress blastings in coal seams aim to destress the local stress concentrations. These blastings are usually performed from the longwall face to decrease the stress level ahead of the longwall. An accurate estimation of active rockburst prevention effectiveness is important during mining under disadvantageous geological and mining conditions, which affect the risk of rockburst. Seismic source parameters characterize the focus of tremor, which may be useful in estimating the destress blasting effects. Investigated destress blastings were performed in coal seam no. 507 during its longwall mining in one of the coal mines in the Upper Silesian Coal Basin under difficult geological and mining conditions. The seismic source parameters of the provoked tremors were calculated. The presented preliminary investigations enable a rapid estimation of the destress blasting effectiveness using seismic source parameters, but further analysis in other geological and mining conditions with other blasting parameters is required.

  7. Evaluation of blast-induced vibration effects on structures 1

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Rim; Jeon, Gyu Shick; Lee, Dae Soo; Joo, Kwang Ho; Lee, Woong Keon [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of); Ryu, Chang Ha; Chung, So Keul; Lee, Kyung Won; Shin, Hee Soon; Chun, Sun Woo; Park, Yeon Jun; Synn, Joong Ho; Choi, Byung Hee [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

    1995-12-31

    Due to the difficulties of obtaining construction site for new plants, following ones are inevitably being built in the site adjacent to existing power plants. Therefore considerable thought has been recently given to the dynamic loading generated by blasting works near the plants to maintain the safety of structures and facilities in power plants. Our own standard for safety level of blast vibration is not prepared yet, and foreign standards have been generally employed without theoretical and experimental verification. Safety-related structures of power plants and facilities have to be protected against the effects of possible hazards due to blast vibration. Earthquakes have been considered a major dynamic design loading as a requirement of plant design, but the effects of blast-induced vibration are not. In order to ensure the safety, rational safe criterion should be established and blast design should be satisfy it, which requires the development of a model for prediction of vibration level through more systematic measurement and analysis. The main objectives of the study are : to provide background data for establishing the rational safe vibration limits, to develop models for prediction of blast vibration level, to establish safe blast design criterion, and to accumulate techniques for field measurements, data acquisition and analysis (author). 80 refs., 347 figs.

  8. Spectrum of abdominal organ injury in a primary blast type

    Directory of Open Access Journals (Sweden)

    Amin Abid

    2009-12-01

    Full Text Available Abstract Introduction Abdominal organ injury in a primary blast type is always challenging for diagnosis. Air containing abdominal viscera is most vulnerable to effects of primary blast injury. In any patient exposed to a primary blast wave who presents with an acute abdomen, an abdominal organ injury is to be kept in a clinical suspicion. Aim Study various abdominal organ injuries occurring in a primary type of blast injury. Material and methods: All those who had exploratory laparotomy for abdominal organ injuries after a primary blast injury for a period of 10 years from January 1998 - January 2008 were included in this retrospective study. Results Total 154 patients had laparotomy for abdominal organ injuries with a primary blast type of injury. Small intestine was damaged in 48 patients (31.1% followed by spleen in 22.7% cases. 54 patients (35.06% had more than one organ injured. Liver laceration was present in 30 patients (19.48%. Multiple small gut perforations were present in 37 patients (77.08%. Negative laparotomy was found in 5 patients (3.24% whereas 3 (1.94% had re-exploration. Mortality was present in 6 patients (3.89%. Conclusions Primary blast injury causes varied abdominal organ injuries. Single or multiple organ damage can be there. Small intestine is commonest viscera injured. Laparotomy gives final diagnosis.

  9. Vacuum-Ultraviolet Photovoltaic Detector.

    Science.gov (United States)

    Zheng, Wei; Lin, Richeng; Ran, Junxue; Zhang, Zhaojun; Ji, Xu; Huang, Feng

    2018-01-23

    Over the past two decades, solar- and astrophysicists and material scientists have been researching and developing new-generation semiconductor-based vacuum ultraviolet (VUV) detectors with low power consumption and small size for replacing traditional heavy and high-energy-consuming microchannel-detection systems, to study the formation and evolution of stars. However, the most desirable semiconductor-based VUV photovoltaic detector capable of achieving zero power consumption has not yet been achieved. With high-crystallinity multistep epitaxial grown AlN as a VUV-absorbing layer for photogenerated carriers and p-type graphene (with unexpected VUV transmittance >96%) as a transparent electrode to collect excited holes, we constructed a heterojunction device with photovoltaic detection for VUV light. The device exhibits an encouraging VUV photoresponse, high external quantum efficiency (EQE) and extremely fast tempera response (80 ns, 10 4 -10 6 times faster than that of the currently reported VUV photoconductive devices). This work has provided an idea for developing zero power consumption and integrated VUV photovoltaic detectors with ultrafast and high-sensitivity VUV detection capability, which not only allows future spacecraft to operate with longer service time and lower launching cost but also ensures an ultrafast evolution of interstellar objects.

  10. Vacuum control system of VEC

    International Nuclear Information System (INIS)

    Roy, Anindya; Bhole, R.B.; Bandopadhyay, D.L.; Mukhopadhyay, B.; Pal, Sarbajit; Sarkar, D.

    2009-01-01

    As a part of modernization of VEC (Variable Energy Cyclotron), the Vacuum Control System is being upgraded to PLC based automated system from initial Relay based Manual system. EPICS (Experimental Physics and Industrial Control System), a standard open source software tool for designing distributed control system, is chosen for developing the supervisory control software layer, leading towards a unified distributed control architecture of VEC Control System. A Modbus - TCP based IOC (I/O Controller) has been developed to communicate control data to PLC using Ethernet-TCP LAN. Keeping in mind, the operators' familiarity with MS-Windows, a MS-Windows based operator interface is developed using VB6. It is also used to test and evaluate EPICS compatibility to MS Windows. Several MS Windows ActiveX components e.g. text display, image display, alarm window, set-point input etc. have been developed incorporating Channel Access library of EPICS. Use of such components ease the programming complexity and reduce developmental time of the operator interface. The system is in the final phase of commissioning. (author)

  11. Baking results of KSTAR vacuum vessel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. T.; Kim, Y. J.; Kim, K. M.; Im, D. S.; Joung, N. Y.; Yang, H. L.; Kim, Y. S.; Kwon, M. [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2009-05-15

    The Korea Superconducting Tokamak Advanced Research (KSTAR) is an advanced superconducting tokamak designed to establish a scientific and technological basis for an attractive fusion reactor. The fusion energy in the tokamak device is released through fusion reactions of light atoms such as deuterium or helium in hot plasma state, of which temperature reaches several hundreds of millions Celsius. The high temperature plasma is created in the vacuum vessel that provides ultra high vacuum status. Accordingly, it is most important for the vacuum condition to keep clean not only inner space but also surface of the vacuum vessel to make high quality plasma. There are two methods planned to clean the wall surface of the KSTAR vacuum vessel. One is surface baking and the other is glow discharge cleaning (GDC). To bake the vacuum vessel, De-Ionized (DI) water is heated to 130 .deg. C and circulated in the passage between double walls of the vacuum vessel (VV) in order to bake the surface. The GDC operation uses hydrogen and inert gas discharges. In this paper, general configuration and brief introduction of the baking result will be reported.

  12. Baking results of KSTAR vacuum vessel

    International Nuclear Information System (INIS)

    Kim, S. T.; Kim, Y. J.; Kim, K. M.; Im, D. S.; Joung, N. Y.; Yang, H. L.; Kim, Y. S.; Kwon, M.

    2009-01-01

    The Korea Superconducting Tokamak Advanced Research (KSTAR) is an advanced superconducting tokamak designed to establish a scientific and technological basis for an attractive fusion reactor. The fusion energy in the tokamak device is released through fusion reactions of light atoms such as deuterium or helium in hot plasma state, of which temperature reaches several hundreds of millions Celsius. The high temperature plasma is created in the vacuum vessel that provides ultra high vacuum status. Accordingly, it is most important for the vacuum condition to keep clean not only inner space but also surface of the vacuum vessel to make high quality plasma. There are two methods planned to clean the wall surface of the KSTAR vacuum vessel. One is surface baking and the other is glow discharge cleaning (GDC). To bake the vacuum vessel, De-Ionized (DI) water is heated to 130 .deg. C and circulated in the passage between double walls of the vacuum vessel (VV) in order to bake the surface. The GDC operation uses hydrogen and inert gas discharges. In this paper, general configuration and brief introduction of the baking result will be reported

  13. Quark and gluon condensate in vacuum

    International Nuclear Information System (INIS)

    Vajnshtejn, A.I.; Zakharov, V.I.; Shifman, M.A.

    1979-01-01

    The mechanism of quark confinement has been reviewed. The fact that coloured particles in a free state cannot be observed is connected with specific properties of vacuum in quantum chromodynamics. The basic hypothesis consists in the existence of vacuum fields, quark and gluon condensates, which affect the coloured objects. The vacuum transparent relative to noncharged ''white'' states serves as a source of the force acting upon the coloured particles. It has been a sucess to examine strictly the action of the vacuum fields on quarks when the distance between them is relatively small and the force of the vacuum fields on quarks is relatively small too. It is shown that the interaction with the vacuum fields manifests itself earlier than the forces connected with the gluon exchange do. It is assumed that the vacuum condensate of quarks and gluons and its relation to properties of resonances and to the bag model exist in reality. The dispersion sum rules are used for calculating masses and lepton widths of resonances

  14. High-speed measurement of firearm primer blast waves

    OpenAIRE

    Courtney, Michael; Daviscourt, Joshua; Eng, Jonathan; Courtney, Amy

    2012-01-01

    This article describes a method and results for direct high-speed measurements of firearm primer blast waves employing a high-speed pressure transducer located at the muzzle to record the blast pressure wave produced by primer ignition. Key findings are: 1) Most of the lead styphnate based primer models tested show 5.2-11.3% standard deviation in the magnitudes of their peak pressure. 2) In contrast, lead-free diazodinitrophenol (DDNP) based primers had standard deviations of the peak blast p...

  15. The tank's dynamic response under nuclear explosion blast wave

    International Nuclear Information System (INIS)

    Xu Mei; Wang Lianghou; Li Xiaotian; Yu Suyuan; Zhang Zhengming; Wan Li

    2005-01-01

    To weapons and equipment, blast wave is the primary destructive factor. In this paper, taken the real model-59 tank as an example, we try to transform the damage estimation problem into computing a fluid structure interaction problem with finite element method. The response of tank under nuclear explosion blast wave is computed with the general-coupling algorithm. Also, the dynamical interaction of blast wave and tank is reflected in real time. The deformation of each part of the tank is worked out and the result corresponds to the real-measured data. (authors)

  16. Lateral blasts at Mount St. Helens and hazard zonation

    Science.gov (United States)

    Crandell, D.R.; Hoblitt, R.P.

    1986-01-01

    Lateral blasts at andesitic and dacitic volcanoes can produce a variety of direct hazards, including ballistic projectiles which can be thrown to distances of at least 10 km and pyroclastic density flows which can travel at high speed to distances of more than 30 km. Indirect effect that may accompany such explosions include wind-borne ash, pyroclastic flows formed by the remobilization of rock debris thrown onto sloping ground, and lahars. Two lateral blasts occurred at a lava dome on the north flank of Mount St. Helens about 1200 years ago; the more energetic of these threw rock debris northeastward across a sector of about 30?? to a distance of at least 10 km. The ballistic debris fell onto an area estimated to be 50 km2, and wind-transported ash and lapilli derived from the lateral-blast cloud fell on an additional lobate area of at least 200 km2. In contrast, the vastly larger lateral blast of May 18, 1980, created a devastating pyroclastic density flow that covered a sector of as much as 180??, reached a maximum distance of 28 km, and within a few minutes directly affected an area of about 550 km2. The May 18 lateral blast resulted from the sudden, landslide-induced depressurization of a dacite cryptodome and the hydrothermal system that surrounded it within the volcano. We propose that lateral-blast hazard assessments for lava domes include an adjoining hazard zone with a radius of at least 10 km. Although a lateral blast can occur on any side of a dome, the sector directly affected by any one blast probably will be less than 180??. Nevertheless, a circular hazard zone centered on the dome is suggested because of the difficulty of predicting the direction of a lateral blast. For the purpose of long-term land-use planning, a hazard assessment for lateral blasts caused by explosions of magma bodies or pressurized hydrothermal systems within a symmetrical volcano could designate a circular potential hazard area with a radius of 35 km centered on the volcano

  17. Protecting the lower extremity against a/p blast mines

    CSIR Research Space (South Africa)

    van Dyk, T

    2006-09-01

    Full Text Available the Lower Extremity against a/p Blast Mines J T van Dyk DEFENCE, PEACE, SAFETY AND SECURITY LANDWARDS SCIENCES COMPETENCY AREA Slide 2 © CSIR 2006 www.csir.co.za Contents • R&D overview • Effect of a/p blast mines • Basic... explosive principles – Shock effect (brisance) – Blast effect • Test methods • Protection concepts • Test results Slide 3 © CSIR 2006 www.csir.co.za Goals: Compare LEAP study results with field injuries Investigate energy...

  18. Scale testing of a partially confined blast chamber

    CSIR Research Space (South Africa)

    Grundling, W

    2012-10-01

    Full Text Available in pressure readings. A scale model of the blast chamber, Emily, was constructed with the addition of a pendulum plate hanging concentrically covering 65% of the open area. PURPOSE OF SCALED BLAST CHAMBER The purpose of this particular test is to evaluate... PHASE Illustrated in Figure 3 and 4 are the results obtained during testing of the scaled blast chamber. In both cases the pressure dissipates over time, showing pulsating behaviour as the shockwaves reflect off the chamber walls. By looking...

  19. Is the Free Vacuum Energy Infinite?

    International Nuclear Information System (INIS)

    Shirazi, S. M.; Razmi, H.

    2015-01-01

    Considering the fundamental cutoff applied by the uncertainty relations’ limit on virtual particles’ frequency in the quantum vacuum, it is shown that the vacuum energy density is proportional to the inverse of the fourth power of the dimensional distance of the space under consideration and thus the corresponding vacuum energy automatically regularized to zero value for an infinitely large free space. This can be used in regularizing a number of unwanted infinities that happen in the Casimir effect, the cosmological constant problem, and so on without using already known mathematical (not so reasonable) techniques and tricks

  20. Gases and vacua handbook of vacuum physics

    CERN Document Server

    Beck, A H

    2013-01-01

    Handbook of Vacuum Physics, Volume 1: Gases and Vacua presents three major topics, which are the fourth to sixth parts of this volume. These topics are the remarks on units of physical quantities; kinetic theory of gases and gaseous flow; and theory of vacuum diffusion pumps. The first topic aims to present concisely the significance of units of physical quantities, catering the need and interest of those who take measurements and make calculations in different fields of vacuum sciences. The technique and applications of this particular topic are also provided. The second main topic focuses sp

  1. Plasma instability of a vacuum arc centrifuge

    International Nuclear Information System (INIS)

    Hole, M.J.; Dallaqua, R.S.; Simpson, S.W.; Del Bosco, E.

    2002-01-01

    Ever since conception of the vacuum arc centrifuge in 1980, periodic fluctuations in the ion saturation current and floating potential have been observed in Langmuir probe measurements in the rotation region of a vacuum arc centrifuge. In this work we develop a linearized theoretical model to describe a range of instabilities in the vacuum arc centrifuge plasma column, and then test the validity of the description through comparison with experiment. We conclude that the observed instability is a 'universal' instability, driven by the density gradient, in a plasma with finite conductivity

  2. Cold vacuum drying facility site evaluation report

    International Nuclear Information System (INIS)

    Diebel, J.A.

    1996-01-01

    In order to transport Multi-Canister Overpacks to the Canister Storage Building they must first undergo the Cold Vacuum Drying process. This puts the design, construction and start-up of the Cold Vacuum Drying facility on the critical path of the K Basin fuel removal schedule. This schedule is driven by a Tri-Party Agreement (TPA) milestone requiring all of the spent nuclear fuel to be removed from the K Basins by December, 1999. This site evaluation is an integral part of the Cold Vacuum Drying design process and must be completed expeditiously in order to stay on track for meeting the milestone

  3. Report of the Synchrotron Radiation Vacuum Workshop

    International Nuclear Information System (INIS)

    Avery, R.T.

    1984-06-01

    The Synchrotron Radiation Vacuum Workshop was held to consider two vacuum-related problems that bear on the design of storage rings and beam lines for synchrotron radiation facilities. These problems are gas desorption from the vacuum chamber walls and carbon deposition on optical components. Participants surveyed existing knowledge on these topics and recommended studies that should be performed as soon as possible to provide more definitive experimental data on these topics. This data will permit optimization of the final design of the Advanced Light Source (ALS) and its associated beam lines. It also should prove useful for other synchrotron radiation facilities as well

  4. Ultra-high vacuum technology for accelerators

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit; Hilleret, Noël; Strubin, Pierre M

    2002-01-01

    The lectures will start with a review of the basics of vacuum physics required to build Ultra High Vacuum (UHV) systems, such as static and dynamic outgassing. Before reviewing the various pumping and measurement devices, including the most modern one like Non Evaporable Getter (NEG) coatings, an overview of adequate materials to be used in UHV systems will be given together with their treatment (e.g. cleaning procedures and bake out). Practical examples based on existing or future accelerators will be used to illustrate the topics. Finally, a short overview of modern vacuum controls and interlocks will be given.

  5. Vacuum anti-shielding of monopoles

    International Nuclear Information System (INIS)

    Goebel, D.J.

    1984-01-01

    This chapter examines the difficulties in calculating the vacuum polarization, or magnetization, induced in the vacuum by a monopole. The usual Lagrangian formalism and consequent Feynman rules do not apply. Another problem is that the interaction strength between the monopole and a charge is not small (unless it vanishes exactly) because it is quantized to half integer values. Perturbation theory is therefore not applicable. The discussed problems are solved by using the old fashioned method of calculating a vacuum expectation value as a sum over single particle modes

  6. Quark virtuality and QCD vacuum condensates

    International Nuclear Information System (INIS)

    Zhou Lijuan; Ma Weixing

    2004-01-01

    Based on the Dyson-Schwinger equations (DSEs) in the 'rainbow' approximation, the authors investigate the quark virtuality in the vacuum state and quantum-chromodynamics (QCD) vacuum condensates. In particular, authors calculate the local quark vacuum condensate and quark-gluon mixed condensates, and then the virtuality of quark. The calculated quark virtualities are λ u,d 2 =0.7 GeV 2 for u, d quarks, and λ s 2 =1.6 GeV 2 for s quark. The theoretical predictions are consistent with empirical values used in QCD sum rules, and also fit to lattice QCD predictions

  7. Vacuum engineering, calculations, formulas, and solved exercises

    CERN Document Server

    Berman, Armand

    1992-01-01

    This book was written with two main objectives in mind-to summarize and organize the vast material of vacuum technology in sets of useful formulas, and to provide a collection of worked out exercises showing how to use these formulas for solving technological problems. It is an ideal reference source for those with little time to devote to a full mathematical treatment of the many problems issued in vacuum practice, but who have a working knowledge of the essentials of vacuum technology, elementary physics, and mathematics. This time saving book employs a problem-solving approach throughout, p

  8. The fine art of preparing a vacuum

    CERN Multimedia

    2006-01-01

    The vacuum chambers, or beam pipes, of the LHC experiments are located right at the interface between the detectors and the accelerator, and are therefore crucial to the LHC project as a whole. In this domain, the ALICE and CMS experiments have just passed an important milestone, with the completion of the first of CMS's two end-cap vacuum chambers, together with the completion and bakeout of an 18-metre section of the ALICE vacuum chamber. These complex projects, for which CERN's AT/VAC Group is responsible, involved dozens of people over a number of years.

  9. Some aspects of vacuum ultraviolet radiation physics

    CERN Document Server

    Damany, Nicole; Vodar, Boris

    2013-01-01

    Some Aspects of Vacuum Ultraviolet Radiation Physics presents some data on the state of research in vacuum ultraviolet radiation in association with areas of physics. Organized into four parts, this book begins by elucidating the optical properties of solids in the vacuum ultraviolet region (v.u.v.), particularly the specific methods of determination of optical constants in v.u.v., the properties of metals, and those of ionic insulators. Part II deals with molecular spectroscopy, with emphasis on the spectra of diatomic and simple polyatomic molecules, paraffins, and condensed phases. Part III

  10. Massive injection of coal and superoxygenated blast into the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Toxopeus, H.L.; Danloy, G.; Franssen, R.; Havelange, O. [Corus, IJmuiden (Netherlands)

    2002-07-01

    The aim of the present project was to demonstrate the industrial feasibility of a massive injection of coal, {+-}270 kg/tHM, combined with a high O{sub 2} enrichment of the blast. The coke rate would thus be reduced to well below 250 kg/tHM. A reference level of 200-220 kg coal/tHM was successfully accomplished. However, the technical condition of the blast furnace hearths overruled all ambitions, the anticipated trial scheme had to be abandoned and no further trials were performed. A very short trial was aborted shortly after reaching an injection level of around 265 coal/tHM, due to excessive generation of very fine sludge originating from incomplete combustion. This forced the operators to investigate the merits of combustion more in depth. At the aimed low coke-rate detailed information about the gas distribution is of utmost importance. Therefore, in conjunction with the industrial tests, CRM designed a gas tracing method. Measurement of the transfer time between the injection point (a tuyere) and the sampling points (on an above-burden probe) would allow deduction of the radial gas distribution. CRM made the design and the start-up of an installation built by Hoogovens on blast furnace 7 of IJmuiden. Since then, repeated measurements have shown that the gas transfer time profiles are consistent with the data measured at the blast furnace top and at the wall. The modifications of the moveable armour position are reflected better and faster on the gas distribution as measured by helium tracing than on the skin flow temperatures.

  11. Experimental investigation of blast mitigation and particle-blast interaction during the explosive dispersal of particles and liquids

    Science.gov (United States)

    Pontalier, Q.; Loiseau, J.; Goroshin, S.; Frost, D. L.

    2018-04-01

    The attenuation of a blast wave from a high-explosive charge surrounded by a layer of inert material is investigated experimentally in a spherical geometry for a wide range of materials. The blast wave pressure is inferred from extracting the blast wave velocity with high-speed video as well as direct measurements with pressure transducers. The mitigant consists of either a packed bed of particles, a particle bed saturated with water, or a homogeneous liquid. The reduction in peak blast wave overpressure is primarily dependent on the mitigant to explosive mass ratio, M/C, with the mitigant material properties playing a secondary role. Relative peak pressure mitigation reduces with distance and for low values of M/C (pressure levels in the mid-to-far field. Solid particles are more effective at mitigating the blast overpressure than liquids, particularly in the near field and at low values of M/C, suggesting that the energy dissipation during compaction, deformation, and fracture of the powders plays an important role. The difference in scaled arrival time of the blast and material fronts increases with M/C and scaled distance, with solid particles giving the largest separation between the blast wave and cloud of particles. Surrounding a high-explosive charge with a layer of particles reduces the positive-phase blast impulse, whereas a liquid layer has no influence on the impulse in the far field. Taking the total impulse due to the blast wave and material impact into account implies that the damage to a nearby structure may actually be augmented for a range of distances. These results should be taken into consideration in the design of explosive mitigant systems.

  12. Is there vacuum when there is mass? Vacuum and non-vacuum solutions for massive gravity

    International Nuclear Information System (INIS)

    Martín-Moruno, Prado; Visser, Matt

    2013-01-01

    Massive gravity is a theory which has a tremendous amount of freedom to describe different cosmologies, but at the same time, the various solutions one encounters must fulfil some rather nontrivial constraints. Most of the freedom comes not from the Lagrangian, which contains only a small number of free parameters (typically three depending on counting conventions), but from the fact that one is in principle free to choose the reference metric almost arbitrarily—which effectively introduces a non-denumerable infinity of free parameters. In the current paper, we stress that although changing the reference metric would lead to a different cosmological model, this does not mean that the dynamics of the universe can be entirely divorced from its matter content. That is, while the choice of reference metric certainly influences the evolution of the physically observable foreground metric, the effect of matter cannot be neglected. Indeed the interplay between matter and geometry can be significantly changed in some specific models; effectively since the graviton would be able to curve the spacetime by itself, without the need of matter. Thus, even the set of vacuum solutions for massive gravity can have significant structure. In some cases, the effect of the reference metric could be so strong that no conceivable material content would be able to drastically affect the cosmological evolution. Dedicated to the memory of Professor Pedro F González–Díaz (paper)

  13. Environmental problems associated with blasting in mines: public apprehensions of damage due to blast vibrations - case studies

    Energy Technology Data Exchange (ETDEWEB)

    Padhi, S.N. [DGMS, Bhubaneswar (India)

    1994-12-31

    Blast vibrations may be felt in intensities as small as 1/100 of that required to cause any damage to structures. Therefore, the public response and thus complaints regarding damages are often imaginary. The paper deals with three case studies, involving alleged damage from blasting in surface and underground coal mines where public litigations and agitations resulted due to such apprehensions. The paper is written in simple technical language as the situations warranted that the blast vibration studies should be understood by the general public. 7 tabs.

  14. Linking blast physics to biological outcomes in mild traumatic brain injury: Narrative review and preliminary report of an open-field blast model.

    Science.gov (United States)

    Song, Hailong; Cui, Jiankun; Simonyi, Agnes; Johnson, Catherine E; Hubler, Graham K; DePalma, Ralph G; Gu, Zezong

    2018-03-15

    Blast exposures are associated with traumatic brain injury (TBI) and blast-induced TBIs are common injuries affecting military personnel. Department of Defense and Veterans Administration (DoD/VA) reports for TBI indicated that the vast majority (82.3%) has been mild TBI (mTBI)/concussion. mTBI and associated posttraumatic stress disorders (PTSD) have been called "the invisible injury" of the current conflicts in Iraq and Afghanistan. These injuries induce varying degrees of neuropathological alterations and, in some cases, chronic cognitive, behavioral and neurological disorders. Appropriate animal models of blast-induced TBI will not only assist the understanding of physical characteristics of the blast, but also help to address the potential mechanisms. This report provides a brief overview of physical principles of blast, injury mechanisms related to blast exposure, current blast animal models, and the neurological behavioral and neuropathological findings related to blast injury in experimental settings. We describe relationships between blast peak pressures and the observed injuries. We also report preliminary use of a highly reproducible and intensity-graded blast murine model carried out in open-field with explosives, and describe physical and pathological findings in this experimental model. Our results indicate close relationships between blast intensities and neuropathology and behavioral deficits, particularly at low level blast intensities relevant to mTBI. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. High vacuum tribology of polycrystalline diamond coatings

    Indian Academy of Sciences (India)

    Polycrystalline diamond coatings; hot filament CVD; high vacuum tribology. 1. Introduction .... is a characteristic of graphite. We mark the (diamond ... coefficient of friction due to changes in substrate temperature. The average coefficient of.

  16. Gravitational collapse and the vacuum energy

    International Nuclear Information System (INIS)

    Campos, M

    2014-01-01

    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.

  17. Analytical and numerical tools for vacuum systems

    CERN Document Server

    Kersevan, R

    2007-01-01

    Modern particle accelerators have reached a level of sophistication which require a thorough analysis of all their sub-systems. Among the latter, the vacuum system is often a major contributor to the operating performance of a particle accelerator. The vacuum engineer has nowadays a large choice of computational schemes and tools for the correct analysis, design, and engineering of the vacuum system. This paper is a review of the different type of algorithms and methodologies which have been developed and employed in the field since the birth of vacuum technology. The different level of detail between simple back-of-the-envelope calculations and more complex numerical analysis is discussed by means of comparisons. The domain of applicability of each method is discussed, together with its pros and cons.

  18. Exact vacuum energy of orbifold lattice theories

    International Nuclear Information System (INIS)

    Matsuura, So

    2007-01-01

    We investigate the orbifold lattice theories constructed from supersymmetric Yang-Mills matrix theories (mother theories) with four and eight supercharges. We show that the vacuum energy of these theories does not receive any quantum correction perturbatively

  19. Design of the ZTH vacuum liner

    International Nuclear Information System (INIS)

    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 2.4m 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 10 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

  20. Cold vacuum drying facility design requirements

    Energy Technology Data Exchange (ETDEWEB)

    Irwin, J.J.

    1997-09-24

    This release of the Design Requirements Document is a complete restructuring and rewrite to the document previously prepared and released for project W-441 to record the design basis for the design of the Cold Vacuum Drying Facility.

  1. Cold vacuum drying facility design requirements

    International Nuclear Information System (INIS)

    Irwin, J.J.

    1997-01-01

    This release of the Design Requirements Document is a complete restructuring and rewrite to the document previously prepared and released for project W-441 to record the design basis for the design of the Cold Vacuum Drying Facility

  2. Topology of classical vacuum space-time

    International Nuclear Information System (INIS)

    Cho, Y.M.

    2007-04-01

    We present a topological classification of classical vacuum space-time. Assuming the 3-dimensional space allows a global chart, we show that the static vacuum space-time of Einstein's theory can be classified by the knot topology π 3 (S 3 ) = π 3 (S 2 ). Viewing Einstein's theory as a gauge theory of Lorentz group and identifying the gravitational connection as the gauge potential of Lorentz group, we construct all possible vacuum gravitational connections which give a vanishing curvature tensor. With this we show that the vacuum connection has the knot topology, the same topology which describes the multiple vacua of SU(2) gauge theory. We discuss the physical implications of our result in quantum gravity. (author)

  3. 2XIIB vacuum vessel: a unique design

    International Nuclear Information System (INIS)

    Hibbs, S.M.; Calderon, M.O.

    1975-01-01

    The 2XIIB mirror confinement experiment makes unique demands on its vacuum system. The confinement coil set encloses a cavity whose surface is comprised of both simple and compound curves. Within this cavity and at the core of the machine is the operating vacuum which is on the order of 10 -9 Torr. The vacuum container fits inside the cavity, presenting an inside surface suitable for titanium getter pumping and a means of removing the heat load imposed by incandescent sublimator wires. In addition, the cavity is constructed of nonmagnetic and nonconducting materials (nonmetals) to avoid distortion of the pulsed confinement field. It is also isolated from mechanical shocks induced in the machine's main structure when the coils are pulsed. This paper describes the design, construction, and operation of the 2XIIB high-vacuum vessel that has been performing successfully since early 1974

  4. Production of Lunar Oxygen Through Vacuum Pyrolysis

    National Research Council Canada - National Science Library

    Matchett, John

    2006-01-01

    .... The vacuum pyrolysis method of oxygen production from lunar regolith presents a viable option for in situ propellant production because of its simple operation involving limited resources from earth...

  5. Design of the CLIC Quadrupole Vacuum Chambers

    CERN Document Server

    Garion, C

    2010-01-01

    The Compact Linear Collider, under study, requires vacuum chambers with a very small aperture, of the order of 8 mm in diameter, and with a length up to around 2 m for the main beam quadrupoles. To keep the very tight geometrical tolerances on the quadrupoles, no bake out is allowed. The main issue is to reach UHV conditions (typically 10-9 mbar static pressure) in a system where the vacuum performance is driven by water outgassing. For this application, a thinwalled stainless steel vacuum chamber with two ante chambers equipped with NEG strips, is proposed. The mechanical design, especially the stability analysis, is shown. The key technologies of the prototype fabrication are given. Vacuum tests are carried out on the prototypes. The test set-up as well as the pumping system conditions are presented.

  6. FRIB driver linac vacuum model and benchmarks

    CERN Document Server

    Durickovic, Bojan; Kersevan, Roberto; Machicoane, Guillaume

    2014-01-01

    The Facility for Rare Isotope Beams (FRIB) is a superconducting heavy-ion linear accelerator that is to produce rare isotopes far from stability for low energy nuclear science. In order to achieve this, its driver linac needs to achieve a very high beam current (up to 400 kW beam power), and this requirement makes vacuum levels of critical importance. Vacuum calculations have been carried out to verify that the vacuum system design meets the requirements. The modeling procedure was benchmarked by comparing models of an existing facility against measurements. In this paper, we present an overview of the methods used for FRIB vacuum calculations and simulation results for some interesting sections of the accelerator. (C) 2013 Elsevier Ltd. All rights reserved.

  7. Theorem on axially symmetric gravitational vacuum configurations

    Energy Technology Data Exchange (ETDEWEB)

    Papadopoulos, A; Le Denmat, G [Paris-6 Univ., 75 (France). Inst. Henri Poincare

    1977-01-24

    A theorem is proved which asserts the non-existence of axially symmetric gravitational vacuum configurations with non-stationary rotation only. The eventual consequences in black-hole physics are suggested.

  8. Re-circulating linac vacuum system

    International Nuclear Information System (INIS)

    Wells, Russell P.; Corlett, John N.; Zholents, Alexander A.

    2003-01-01

    The vacuum system for a proposed 2.5 GeV, 10ΜA recirculating linac synchrotron light source [1] is readily achievable with conventional vacuum hardware and established fabrication processes. Some of the difficult technical challenges associated with synchrotron light source storage rings are sidestepped by the relatively low beam current and short beam lifetime requirements of a re-circulating linac. This minimal lifetime requirement leads directly to relatively high limits on the background gas pressure through much of the facility. The 10ΜA average beam current produces very little synchrotron radiation induced gas desorption and thus the need for an ante-chamber in the vacuum chamber is eliminated. In the arc bend magnets, and the insertion devices, the vacuum chamber dimensions can be selected to balance the coherent synchrotron radiation and resistive wall wakefield effects, while maintaining the modest limits on the gas pressure and minimal outgassing

  9. High Vacuum Techniques for Anionic Polymerization

    KAUST Repository

    Ratkanthwar, Kedar; Hadjichristidis, Nikolaos; Mays, Jimmy

    2015-01-01

    Anionic polymerization high vacuum techniques (HVTs) are the most suitable for the preparation of polymer samples with well-defined complex macromolecular architectures. Though HVTs require glassblowing skill for designing and making polymerization

  10. Seismic stations with GSM telemetry for registration of quarry blasts

    Czech Academy of Sciences Publication Activity Database

    Brož, Milan; Číž, Radim; Málek, Jiří; Žanda, Libor

    2000-01-01

    Roč. 2000, 16 (118) (2000), s. 25-32 ISSN 1211-1910 Institutional research plan: CEZ:AV0Z3046908 Keywords : blasting * seismic station * GSM mobile modem Subject RIV: DC - Siesmology, Volcanology, Earth Structure

  11. Analysing Blast and Fragment Penetration Effects on Composite Helicopter Structures

    National Research Council Canada - National Science Library

    van't Hof, C; Herlaar, K; Luyten, J. M; van der Jagt, M. J

    2005-01-01

    .... The last decades the threat of helicopters has increased in military circumstances. Consequently the helicopters will be exposed to weapon effects like high blast loads and fragment impact more frequently...

  12. Gene interactions and genetics of blast resistance and yield ...

    Indian Academy of Sciences (India)

    2014-08-11

    Aug 11, 2014 ... of chemical measures for the control and management of blast, which are not .... tion of genetic components of variation, epistasis model and gene effects in two .... and environmental variance is estimated from mean variance.

  13. Seismic safety in conducting large-scale blasts

    Science.gov (United States)

    Mashukov, I. V.; Chaplygin, V. V.; Domanov, V. P.; Semin, A. A.; Klimkin, M. A.

    2017-09-01

    In mining enterprises to prepare hard rocks for excavation a drilling and blasting method is used. With the approach of mining operations to settlements the negative effect of large-scale blasts increases. To assess the level of seismic impact of large-scale blasts the scientific staff of Siberian State Industrial University carried out expertise for coal mines and iron ore enterprises. Determination of the magnitude of surface seismic vibrations caused by mass explosions was performed using seismic receivers, an analog-digital converter with recording on a laptop. The registration results of surface seismic vibrations during production of more than 280 large-scale blasts at 17 mining enterprises in 22 settlements are presented. The maximum velocity values of the Earth’s surface vibrations are determined. The safety evaluation of seismic effect was carried out according to the permissible value of vibration velocity. For cases with exceedance of permissible values recommendations were developed to reduce the level of seismic impact.

  14. Measurement and Modelling of Blast Movement to Reduce Ore ...

    African Journals Online (AJOL)

    user

    geologists at Newmont Ahafo Mine have realised the impact of blast movement on ore losses and dilution and have ... Movement to Reduce Ore Losses and Dilution at Ahafo Gold Mine in Ghana”, Ghana Mining Journal, pp. .... classification.

  15. Evaluation of Grade 120 Granulated Ground blast Furnace Slag.

    Science.gov (United States)

    1999-06-01

    This study evaluates Grade 120 Granulated Ground Blast Furnace Slag (GGBFS) and its effect on the properties of hydraulic cement concretes used in structural and pavement construction. Several mix designs, structural and pavement, were used for this ...

  16. Assessment of Environmental Effects of Post-Blasted Explosive on ...

    African Journals Online (AJOL)

    PROF HORSFALL

    Assessment of Environmental Effects of Post-Blasted Explosive on the Ecosystem of Old ... intensity and temperature of explosive dissolution in the mine environment shows that TNT ... based on their physical/chemical properties as: gelatin.

  17. An Operational Model for the Prediction of Jet Blast

    Science.gov (United States)

    2012-01-09

    This paper presents an operational model for the prediction of jet blast. The model was : developed based upon three modules including a jet exhaust model, jet centerline decay : model and aircraft motion model. The final analysis was compared with d...

  18. Blast Impact Prediction Studies at Ghana Manganese Company ...

    African Journals Online (AJOL)

    Michael

    2015-06-01

    Jun 1, 2015 ... Keywords: Blast impact, Environment, Prediction, Regulatory threshold. 1 Introduction ... Noise is an environmental nuisance. .... explosion energy released into the ground generates vibration waves within the rock. Several.

  19. Damage to underground coal mines caused by surface blasting

    International Nuclear Information System (INIS)

    Fourie, A.B.; Green, R.W.

    1993-01-01

    An investigation of the potential damage to underground coal workings as a result of surface blasting at an opencast coal mine is described. Seismometers were installed in a worked out area of an underground mine, in the eastern Transvaal region of South Africa, and the vibration caused by nearby surface blasting recorded. These measurements were used to derive peak particle velocities. These velocities were correlated with observed damage underground in order to establish the allowable combination of the two blasting parameters of charge mass per relay, and blast-to-gage point distance. An upper limit of 110mm/sec peak particle velocity was found to be sufficient to ensure that the damage to the particular workings under consideration was minimal. It was further found that a cube-root scaling law provided a better fit to the field data than the common square-root law. 11 refs., 6 figs., 5 tabs

  20. Blast overpressure after tire explosion: a fatal case.

    Science.gov (United States)

    Pomara, Cristoforo; D'Errico, Stefano; Riezzo, Irene; Perilli, Gabriela; Volpe, Umberto; Fineschi, Vittorio

    2013-12-01

    Fatal blast injuries are generally reported in literature as a consequence of the detonation of explosives in war settings. The pattern of lesion depends on the position of the victim in relation to the explosion, on whether the blast tracks through air or water, and whether it happens in the open air or within an enclosed space and the distance from the explosion. Tire explosion-related injuries are rarely reported in literature. This study presents a fatal case of blast overpressure due to the accidental explosion of a truck tire occurring in a tire repair shop. A multidisciplinary approach to the fatality involving forensic pathologists and engineers revealed that the accidental explosion, which caused a series of primary and tertiary blast wave injuries, was due to tire deterioration.

  1. Blast Load Response of Steel Sandwich Panels with Liquid Encasement

    Energy Technology Data Exchange (ETDEWEB)

    Dale Karr; Marc Perlin; Benjamin Langhorst; Henry Chu

    2009-10-01

    We describe an experimental investigation of the response of hybrid blast panels for protection from explosive and impact forces. The fundamental notion is to dissipate, absorb, and redirect energy through plastic collapse, viscous dissipation, and inter-particle forces of liquid placed in sub-structural compartments. The panels are designed to absorb energy from an impact or air blast by elastic-plastic collapse of the panel substructure that includes fluid-filled cavities. The fluid contributes to blast effects mitigation by providing increased initial mass and resistance, by dissipation of energy through viscosity and fluid flow, and by redirecting the momentum that is imparted to the system from the impact and blast impulse pressures. Failure and deformation mechanisms of the panels are described.

  2. Vacuum ultraviolet photochemistry of tetrahydrothiophene and sulfolane

    International Nuclear Information System (INIS)

    Scala, A.A.; Colon, I.

    1979-01-01

    The vacuum uv photolysis of tetrahydrothiophene (THT) involves the breaking of the S to α-C bond. Besides ethylene, C 3 H 6 and 1,3-butadiene are also formed. Photolyses of THT, tetrahydrofuran, and pyrrolidine are similar. The vacuum uv photolysis of tetramethylene sulfone (sulfolane) was also studied; products are SO 2 , cyclobutane, 1-butene, and ethylene. No cis-2-butene was observed

  3. Vacuum-plasma coverings on the aircraft

    International Nuclear Information System (INIS)

    Shvetsov, V.D.; Teksin, Eh.K.; Lysyak, A.A.

    1998-01-01

    In the article are considered the perspectives of vacuum-plasma coverings using for engine components protection. The influence of operating factors on the durability of components which has the vacuum-plasma coverings is show.Leads in using the concept of informational parameter of quality.The recommendation about organization of engine with abolished components maintenance by methods of flyable conditions or reliability level are given

  4. The Effect of Forcing on Vacuum Radiation

    OpenAIRE

    Jones-Smith, Katherine; Mathur, Harsh; Lowenstein, Ashton

    2018-01-01

    Vacuum radiation has been the subject of theoretical study in both cosmology and condensed matter physics for many decades. Recently there has been impressive progress in experimental realizations as well. Here we study vacuum radiation when a field mode is driven both parametrically and by a classical source. We find that in the Heisenberg picture the field operators of the mode undergo a Bogolyubov transformation combined with a displacement, in the Schr\\"odinger picture the oscillator evol...

  5. Cluster expansion for vacuum confining fields

    International Nuclear Information System (INIS)

    Simonov, Yu.A.

    1987-01-01

    Colored particle Green functions in vacuum background random fields are written as path integrals. Averaging over random fields is done using the cluster (cumulant) expansion. The existence of a finite correlation length for vacuum background fields is shown to produce the linear confinement, in agreement with the results, obtained with the help of averaged Hamiltonians. A modified form of cluster expansion for nonabelian fields is introduced using the path-ordered cumulants

  6. Vacuum decay in an interacting multiverse

    Science.gov (United States)

    Robles-Pérez, S.; Alonso-Serrano, A.; Bastos, C.; Bertolami, O.

    2016-08-01

    We examine a new multiverse scenario in which the component universes interact. We focus our attention to the process of "true" vacuum nucleation in the false vacuum within one single element of the multiverse. It is shown that the interactions lead to a collective behavior that might lead, under specific conditions, to a pre-inflationary phase and ensued distinguishable imprints in the comic microwave background radiation.

  7. Vacuum decay in an interacting multiverse

    Energy Technology Data Exchange (ETDEWEB)

    Robles-Pérez, S. [Centro de Física “Miguel Catalán”, Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 121, 28006 Madrid (Spain); Estación Ecológica de Biocosmología, Pedro de Alvarado, 14, 06411 Medellín (Spain); Alonso-Serrano, A. [Centro de Física “Miguel Catalán”, Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 121, 28006 Madrid (Spain); Estación Ecológica de Biocosmología, Pedro de Alvarado, 14, 06411 Medellín (Spain); School of Mathematics and Statistics, Victoria University of Wellington, PO Box 600, Wellington 6140 (New Zealand); Bastos, C., E-mail: catarina.bastos@tecnico.ulisboa.pt [GoLP, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Avenida Rovisco Pais 1, 1049-001 Lisboa (Portugal); Bertolami, O. [Departamento de Física e Astronomia and Centro de Física do Porto, Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto (Portugal)

    2016-08-10

    We examine a new multiverse scenario in which the component universes interact. We focus our attention to the process of “true” vacuum nucleation in the false vacuum within one single element of the multiverse. It is shown that the interactions lead to a collective behavior that might lead, under specific conditions, to a pre-inflationary phase and ensued distinguishable imprints in the comic microwave background radiation.

  8. Vacuum decay in an interacting multiverse

    Directory of Open Access Journals (Sweden)

    S. Robles-Pérez

    2016-08-01

    Full Text Available We examine a new multiverse scenario in which the component universes interact. We focus our attention to the process of “true” vacuum nucleation in the false vacuum within one single element of the multiverse. It is shown that the interactions lead to a collective behavior that might lead, under specific conditions, to a pre-inflationary phase and ensued distinguishable imprints in the comic microwave background radiation.

  9. Vacuum decay in an interacting multiverse

    International Nuclear Information System (INIS)

    Robles-Pérez, S.; Alonso-Serrano, A.; Bastos, C.; Bertolami, O.

    2016-01-01

    We examine a new multiverse scenario in which the component universes interact. We focus our attention to the process of “true” vacuum nucleation in the false vacuum within one single element of the multiverse. It is shown that the interactions lead to a collective behavior that might lead, under specific conditions, to a pre-inflationary phase and ensued distinguishable imprints in the comic microwave background radiation.

  10. On microscopic structure of the QCD vacuum

    Science.gov (United States)

    Pak, D. G.; Lee, Bum-Hoon; Kim, Youngman; Tsukioka, Takuya; Zhang, P. M.

    2018-05-01

    We propose a new class of regular stationary axially symmetric solutions in a pure QCD which correspond to monopole-antimonopole pairs at macroscopic scale. The solutions represent vacuum field configurations which are locally stable against quantum gluon fluctuations in any small space-time vicinity. This implies that the monopole-antimonopole pair can serve as a structural element in microscopic description of QCD vacuum formation.

  11. Constrained potential method for false vacuum decays

    International Nuclear Information System (INIS)

    Park, Jae-hyeon

    2010-11-01

    A procedure is reported for numerical analysis of false vacuum transition in a model with multiple scalar fields. It is a refined version of the approach by Konstandin and Huber. The alteration makes it possible to tackle a class of problems that was difficult or unsolvable with the original method, i.e. those with a distant or nonexistent true vacuum. An example with an unbounded-from-below direction is presented. (orig.)

  12. Vacuum level effects on gait characteristics for unilateral transtibial amputees with elevated vacuum suspension.

    Science.gov (United States)

    Xu, Hang; Greenland, Kasey; Bloswick, Donald; Zhao, Jie; Merryweather, Andrew

    2017-03-01

    The elevated vacuum suspension system has demonstrated unique health benefits for amputees, but the effect of vacuum pressure values on gait characteristics is still unclear. The purpose of this study was to investigate the effects of elevated vacuum levels on temporal parameters, kinematics and kinetics for unilateral transtibial amputees. Three-dimensional gait analysis was conducted in 9 unilateral transtibial amputees walking at a controlled speed with five vacuum levels ranging from 0 to 20inHg, and also in 9 able-bodied subjects walking at self-preferred speed. Repeated ANOVA and Dunnett's t-test were performed to determine the effect of vacuum level and limb for within subject and between groups. The effect of vacuum level significantly affected peak hip external rotation and external knee adduction moment. Maximum braking and propulsive ground reaction forces generally increased for the residual limb and decreased for the intact limb with increasing vacuum. Additionally, the intact limb experienced an increased loading due to gait asymmetry for several variables. There was no systematic vacuum level effect on gait. Higher vacuum levels, such as 15 and 20inHg, were more comfortable and provided some relief to the intact limb, but may also increase the risk of osteoarthritis of the residual limb due to the increased peak external hip and knee adduction moments. Very low vacuum should be avoided because of the negative effects on gait symmetry. A moderate vacuum level at 15inHg is suggested for unilateral transtibial amputees with elevated vacuum suspension. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Blast response of corroded steel plates

    Energy Technology Data Exchange (ETDEWEB)

    Eslamimajd, Alireza; RahbarRanji, Ahmad [AmirKabir University of Technology, Tehran (Korea, Republic of)

    2014-05-15

    Numerical results for one- and both-sided corroded steel plates subjected to blast loading are presented. Finite element analysis, with ABAQUS software, is employed to determine the deformation and stress distributions. The results for the case of triangular pulse pressure on un-corroded plates are validated against literature-based data and then, detailed parametric studies are carried-out. The effects of influential parameters including, plate aspect ratio, degree of pit and different ratio of pit depth at each sides of the plate are investigated. The results show that position of pitted surface in respect to applied pressure is the most influential parameter on reduction of dynamic load carrying capacity of pitted plates. By increasing degree of pitting, reduction of dynamic load carrying capacity decrease more.

  14. Power Tillers for Demining: Blast Test

    Directory of Open Access Journals (Sweden)

    Emanuela Elisa Cepolina

    2007-06-01

    Full Text Available Power tillers are very simple and versatile machines with large scale diffusion in developing countries, where they are commonly used both for agriculture and for transportation purposes. A new integrated participatory approach that makes use of and improves local end-users knowledge has been used to design a new robotic system for humanitarian demining applications in Sri Lanka, using power tiller as core module. A demining machine composed by a tractor unit, a ground processing tool and a vegetation cutting tool is here presented together with results obtained from the first blast test on the preliminary version of tractor unit armouring. Different breakable connections between wheels and axle have been designed to cause physical detachment and interrupt the transmission of the shock wave released by the explosion of a mine under one wheel. Effects of explosions on different types of wheels and on the chassis have been recorded and commented.

  15. Power Tillers for Demining: Blast Test

    Directory of Open Access Journals (Sweden)

    Emanuela Elisa Cepolina

    2008-11-01

    Full Text Available Power tillers are very simple and versatile machines with large scale diffusion in developing countries, where they are commonly used both for agriculture and for transportation purposes. A new integrated participatory approach that makes use of and improves local end-users knowledge has been used to design a new robotic system for humanitarian demining applications in Sri Lanka, using power tiller as core module. A demining machine composed by a tractor unit, a ground processing tool and a vegetation cutting tool is here presented together with results obtained from the first blast test on the preliminary version of tractor unit armouring. Different breakable connections between wheels and axle have been designed to cause physical detachment and interrupt the transmission of the shock wave released by the explosion of a mine under one wheel. Effects of explosions on different types of wheels and on the chassis have been recorded and commented.

  16. Performance evaluation on vacuum pumps using nanolubricants

    Energy Technology Data Exchange (ETDEWEB)

    Lue, Yeou Feng; Hsu, Yu Chun; Teng, Tun Ping [Dept. of Industrial EducationNational Taiwan Normal University, Taiwan (China)

    2016-09-15

    This study produced alumina (Al{sub 2}O{sub 3}) nanovacuum-pump lubricants (NVALs) by involving the dispersion of Al{sub 2}O{sub 3} nanoparticles in a vacuum-pump lubricant (VAL) with oleic as a dispersant. Experiments were conducted to evaluate the suspension performance, thermal conductivity, viscosity, specific heat, tribological performance and vacuum-pump performance of the NVALs. The experimental results obtained from the vacuum-pump performance tests show that the NVALs with Al{sub 2}O{sub 3} concentration of 0.2 wt.% and oleic concentration of 0.025 wt.% yielded the lowest electricity consumption, conserving 2.39% of electricity compared with the VAL. No marked difference was observed between the temperatures of the vacuum pump using VAL and NVAL. Furthermore, evacuation (i.e., the minimal pressure of -99.5 kPa) was reached faster by the vacuum pump with the NVALs, and the evacuation time could be reduced by 4.91% under optimal conditions. In addition, the vacuum pump with the NVALs exhibited superior overall effectiveness under relatively lower ambient temperatures.

  17. Manufacture of superhigh vacuum testing tank

    International Nuclear Information System (INIS)

    Sakai, Kusuo; Suzui, Koichi; Horigome, Toshio

    1981-01-01

    This apparatus is one of the preliminary experiment equipments for the vacuum system of a UVSOR, and the main objective is to obtain the clean vacuum below 10 - 10 Torr. From the viewpoint of manufacture, there is no problem, but all the works from the design through manufacture, assembling and adjustment of the apparatus, to the obtaining of required vacuum were carried out by the authors themselves. The design and its points, and manufacture are described. In order to obtain clean vacuum and maintain it for long period, the surface cleaning of vacuum tanks is very important. Therefore the method of electrolytic polishing was adopted for the purpose, and its effectiveness was examined. After the surface treatment by two methods, the evacuation test was carried out, and the attained pressure was compared. Electrolytic polishing seemed to be effective. As the method of suppressing surface degasification, there is argon bombardment method. It was attempted to improve the pressure attained by baking only further by this method. By baking at 250 deg C for 30 hr only, the final pressure attained was 1.7 x 10 - 10 Torr, and by making argon bombardment twice during baking, it was 0.9 x 10 - 10 Torr, thus slight improvement was obtained. The main objective to obtain vacuum below 10 - 10 Torr was accomplished, but surface treatment requires more experience. (Kako, I.)

  18. Cosmological evolution of vacuum and cosmic acceleration

    International Nuclear Information System (INIS)

    Kaya, Ali

    2010-01-01

    It is known that the unregularized expressions for the stress-energy tensor components corresponding to subhorizon and superhorizon vacuum fluctuations of a massless scalar field in a Friedmann-Robertson-Walker background are characterized by the equation of state parameters ω = 1/3 and ω = -1/3, which are not sufficient to produce cosmological acceleration. However, the form of the adiabatically regularized finite stress-energy tensor turns out to be completely different. By using the fact that vacuum subhorizon modes evolve nearly adiabatically and superhorizon modes have ω = -1/3, we approximately determine the regularized stress-energy tensor, whose conservation is utilized to fix the time dependence of the vacuum energy density. We then show that vacuum energy density grows from zero up to H 4 in about one Hubble time, vacuum fluctuations give positive acceleration of the order of H 4 /M 2 p and they can completely alter the cosmic evolution of the universe dominated otherwise by the cosmological constant, radiation or pressureless dust. Although the magnitude of the acceleration is tiny to explain the observed value today, our findings indicate that the cosmological backreaction of vacuum fluctuations must be taken into account in early stages of cosmic evolution.

  19. Use of vacuum in processing of uranium

    International Nuclear Information System (INIS)

    Saify, M.T.; Rai, C.B.; Singh, S.P.; Singh, R.P.

    2003-01-01

    Full text: Natural uranium in the form of metal and alloys with suitable heat treatment are being used as fuel in research and some of the power reactors. The fuel is required to satisfy the purity specification from the criteria of neutron economy, corrosion resistance and fabricability. Uranium and its alloys fall under the category of reactive materials. They readily react with atmospheric air to form oxides. If molten uranium is exposed to atmosphere, it reacts violently with atmospheric gases and moisture, leading to explosion in extreme cases. Hence, protective inert atmosphere or high vacuum is required in processing of the materials especially during the melting and casting operation. Vacuum is preferred for melting and remelting of metals and alloys to remove the gaseous and high volatile impurities, to improve the mechanical properties of the material. Also, under vacuum sound castings are produced for further processing by mechanical working or use in casting forms. The addition of reactive alloying elements in uranium is efficiently carried out under vacuum. The paper highlights vacuum systems deployed and applications of vacuum in various operations involved in the processing of uranium and its alloys

  20. Vacuum leak test technique of JT-60

    International Nuclear Information System (INIS)

    Kaminaga, Atsushi; Arai, Takashi; Kodama, Kozo; Sasaki, Noboru; Saidoh, Masahiro

    1998-01-01

    Since a vacuum vessel of JT-60 is very large (167 m 3 ) and is combined with many components, such as magnetic coils, neutral beam injection systems and RF heating systems, etc., the position of leak testing exceeds 700. The two kind of techniques for vacuum leak test used in JT-60 has been described. Firstly the probe helium gas can be fed remotely in the three-dimensionally sectioned 54 regions of the JT-60 torus. The leak test was very rapidly performed by using this method. Secondly the helium detector system has been modified by the additional installation of the cryopump, which reduced the background level of the deuterium gas. The sensitivity of vacuum leak test with the cryopump was two orders of magnitude larger than that of without it. The examples of the performed vacuum leak test are stated. The vacuum leaks during experiments were 9 times. They were caused by thermal strain and plasma discharge. The vacuum leaks just after maintenance are 36 times which mainly caused by mis-installation. (author)

  1. Blasting detonators incorporating semiconductor bridge technology

    Energy Technology Data Exchange (ETDEWEB)

    Bickes, R.W. Jr.

    1994-05-01

    The enormity of the coal mine and extraction industries in Russia and the obvious need in both Russia and the US for cost savings and enhanced safety in those industries suggests that joint studies and research would be of mutual benefit. The author suggests that mine sites and well platforms in Russia offer an excellent opportunity for the testing of Sandia`s precise time-delay semiconductor bridge detonators, with the potential for commercialization of the detonators for Russian and other world markets by both US and Russian companies. Sandia`s semiconductor bridge is generating interest among the blasting, mining and perforation industries. The semiconductor bridge is approximately 100 microns long, 380 microns wide and 2 microns thick. The input energy required for semiconductor bridge ignition is one-tenth the energy required for conventional bridgewire devices. Because semiconductor bridge processing is compatible with other microcircuit processing, timing and logic circuits can be incorporated onto the chip with the bridge. These circuits can provide for the precise timing demanded for cast effecting blasting. Indeed tests by Martin Marietta and computer studies by Sandia have shown that such precise timing provides for more uniform rock fragmentation, less fly rock, reduce4d ground shock, fewer ground contaminants and less dust. Cost studies have revealed that the use of precisely timed semiconductor bridges can provide a savings of $200,000 per site per year. In addition to Russia`s vast mineral resources, the Russian Mining Institute outside Moscow has had significant programs in rock fragmentation for many years. He anticipated that collaborative studies by the Institute and Sandia`s modellers would be a valuable resource for field studies.

  2. Investigations of primary blast-induced traumatic brain injury

    Science.gov (United States)

    Sawyer, T. W.; Josey, T.; Wang, Y.; Villanueva, M.; Ritzel, D. V.; Nelson, P.; Lee, J. J.

    2018-01-01

    The development of an advanced blast simulator (ABS) has enabled the reproducible generation of single-pulse shock waves that simulate free-field blast with high fidelity. Studies with rodents in the ABS demonstrated the necessity of head restraint during head-only exposures. When the head was not restrained, violent global head motion was induced by pressures that would not produce similar movement of a target the size and mass of a human head. This scaling artefact produced changes in brain function that were reminiscent of traumatic brain injury (TBI) due to impact-acceleration effects. Restraint of the rodent head eliminated these, but still produced subtle changes in brain biochemistry, showing that blast-induced pressure waves do cause brain deficits. Further experiments were carried out with rat brain cell aggregate cultures that enabled the conduct of studies without the gross movement encountered when using rodents. The suspension nature of this model was also exploited to minimize the boundary effects that complicate the interpretation of primary blast studies using surface cultures. Using this system, brain tissue was found not only to be sensitive to pressure changes, but also able to discriminate between the highly defined single-pulse shock waves produced by underwater blast and the complex pressure history exposures experienced by aggregates encased within a sphere and subjected to simulated air blast. The nature of blast-induced primary TBI requires a multidisciplinary research approach that addresses the fidelity of the blast insult, its accurate measurement and characterization, as well as the limitations of the biological models used.

  3. OPTIMALIZATION OF BLASTING IN »LAKOVIĆI« LIMESTONE QUARRY

    OpenAIRE

    Branko Božić; Karlo Braun

    1992-01-01

    The optimalization of exploitation in »Lakovići« limestone quarry is described. Based on determined discontinuities in the rock mass and their densities, the best possible working site have been located in order to obtain the best possible sizes of blasted rocks and work slope stability. Optimal lowest resistance line size for the quarry has been counted and proved experimentally. New blasting parameters have resulted in considerable saving of drilling and explosive (the paper is published in...

  4. The Pre-Blast Concept for use on Armour Materials

    Science.gov (United States)

    2016-02-01

    distribution is displayed. The (1 1 1) pole figure for TWIP steel (FCC crystal structure) is shown representatively, while (1 0 0) is chosen for Dual...avoid the blasted plates impacting the ceiling of the blast chamber. A type ‘k’ thermocouple was then welded to a corner on the top side of the plates...angle distribution is displayed. The (1 1 1) pole figure for TWIP steel (FCC crystal structure) is shown representatively, while (1 0 0) is chosen

  5. Study of wet blasting of components in nuclear power stations

    International Nuclear Information System (INIS)

    Hall, J.

    1999-12-01

    This report looks at the method of wet blasting radioactive components in nuclear power stations. The wet blaster uses pearl shaped glass beads with the dimensions of 150-250 μm mixed with water as blasting media. The improved design, providing outer operator's positions with proper radiation protection and more efficient blasting equipment has resulted in a lesser dose taken by the operators. The main reason to decontaminate components in nuclear power plants is to enable service on these components. On components like valves, pump shafts, pipes etc. oxides form and bind radiation. These components are normally situated at some distance from the reactor core and will mainly suffer from radiation from so called activation products. When a component is to be decontaminated it can be decontaminated to a radioactive level where it will be declassified. This report has found levels ranging from 150-1000 Bq/kg allowing declassification of radioactive materials. This difference is found between different countries and different organisations. The report also looks at the levels of waste generated using wet blasting. This is done by tracking the contamination to determine where it collects. It is either collected in the water treatment plant or collected in the blasting media. At Barsebaeck the waste levels, from de-contaminating nearly 800 components in one year, results in a waste volume of about 0,250 m 3 . This waste consists of low and medium level waste and will cost about 3 600 EURO to store. The conclusions of the report are that wet blasting is an indispensable way to treat contaminated components in modern nuclear power plants. The wet blasting equipment can be improved by using a robot enabling the operators to remotely treat components from the outer operator's positions. There they will benefit from better radiation protection thus further reduce their taken dose. The wet blasting equipment could also be used to better control the levels of radioactivity on

  6. PaperBLAST: Text Mining Papers for Information about Homologs.

    Science.gov (United States)

    Price, Morgan N; Arkin, Adam P

    2017-01-01

    Large-scale genome sequencing has identified millions of protein-coding genes whose function is unknown. Many of these proteins are similar to characterized proteins from other organisms, but much of this information is missing from annotation databases and is hidden in the scientific literature. To make this information accessible, PaperBLAST uses EuropePMC to search the full text of scientific articles for references to genes. PaperBLAST also takes advantage of curated resources (Swiss-Prot, GeneRIF, and EcoCyc) that link protein sequences to scientific articles. PaperBLAST's database includes over 700,000 scientific articles that mention over 400,000 different proteins. Given a protein of interest, PaperBLAST quickly finds similar proteins that are discussed in the literature and presents snippets of text from relevant articles or from the curators. PaperBLAST is available at http://papers.genomics.lbl.gov/. IMPORTANCE With the recent explosion of genome sequencing data, there are now millions of uncharacterized proteins. If a scientist becomes interested in one of these proteins, it can be very difficult to find information as to its likely function. Often a protein whose sequence is similar, and which is likely to have a similar function, has been studied already, but this information is not available in any database. To help find articles about similar proteins, PaperBLAST searches the full text of scientific articles for protein identifiers or gene identifiers, and it links these articles to protein sequences. Then, given a protein of interest, it can quickly find similar proteins in its database by using standard software (BLAST), and it can show snippets of text from relevant papers. We hope that PaperBLAST will make it easier for biologists to predict proteins' functions.

  7. Application of Grid Planning Method in Drilling-Blasting Operations

    OpenAIRE

    Dambov, Risto; Spasovski, Orce

    2012-01-01

    The problem occurs almost every day in operation and causes troubles to mining engineers. The right performance of drilling-blasting work is important for the successful operation of the entire excavation. The aim of the paper is to point out the importance of planning and how it can contribute to the right organization and make drilling-blasting and other mining activities in mine operations easier. Defining the activities and practical example that has been given are carried out by the u...

  8. Introduction to vacuum technology: supplementary study material developed for IVS sponsored vacuum courses

    International Nuclear Information System (INIS)

    Bhusan, K.G.

    2008-01-01

    Vacuum technology has advanced to a large extent mainly from the demands of experimental research scientists who have more than ever understood the need for clean very low pressure environments. This need only seems to increase as the lowest pressures achievable in a laboratory setup are dropping down by the decade. What is not usually said is that conventional techniques of producing ultrahigh vacuum have also undergone a metamorphosis in order to cater to the multitude of restrictions in modern day scientific research. This book aims to give that practical approach to vacuum technology. The basics are given in the first chapter with more of a definition oriented approach - which is practically useful. The second chapter deals with the production of vacuum and ultrahigh vacuum with an emphasis on the working principles of several pumps and their working pressure ranges. Measurement of low pressures, both total and partial is presented in the third chapter with a note on leak detection and mass spectrometric techniques. Chapter 4 gives an overview of the materials that are vacuum compatible and their material properties. Chapter 5 gives the necessary methods to be followed for cleaning of vacuum components especially critical if ultrahigh vacuum environment is required. The practical use of a ultrahigh vacuum environment is demonstrated in Chapter 6 for production of high quality thin films through vapour deposition

  9. Comprehensive Numerical Modeling of the Blast Furnace Ironmaking Process

    Science.gov (United States)

    Zhou, Chenn; Tang, Guangwu; Wang, Jichao; Fu, Dong; Okosun, Tyamo; Silaen, Armin; Wu, Bin

    2016-05-01

    Blast furnaces are counter-current chemical reactors, widely utilized in the ironmaking industry. Hot reduction gases injected from lower regions of the furnace ascend, reacting with the descending burden. Through this reaction process, iron ore is reduced into liquid iron that is tapped from the furnace hearth. Due to the extremely harsh environment inside the blast furnace, it is difficult to measure or observe internal phenomena during operation. Through the collaboration between steel companies and the Center for Innovation through Visualization and Simulation, multiple computational fluid dynamics (CFD) models have been developed to simulate the complex multiphase reacting flow in the three regions of the furnace, the shaft, the raceway, and the hearth. The models have been used effectively to troubleshoot and optimize blast furnace operations. In addition, the CFD models have been integrated with virtual reality. An interactive virtual blast furnace has been developed for training purpose. This paper summarizes the developments and applications of blast furnace CFD models and the virtual blast furnace.

  10. Characterization of viscoelastic materials for low-magnitude blast mitigation

    Science.gov (United States)

    Bartyczak, S.; Mock, W.

    2014-05-01

    Recent research indicates that exposure to low amplitude blast waves, such as IED detonation or multiple firings of a weapon, causes damage to brain tissue resulting in Traumatic Brain Injury (TBI) and Post Traumatic Stress Disorder (PTSD). Current combat helmets are not sufficiently protecting warfighters from this danger and the effects are debilitating, costly, and long-lasting. The objective of the present work is to evaluate the blast mitigating behavior of current helmet materials and new materials designed for blast mitigation using a test fixture recently developed at the Naval Surface Warfare Center Dahlgren Division for use with an existing gas gun. The 40-mm-bore gas gun was used as a shock tube to generate blast waves (ranging from 0.5 to 2 bar) in the test fixture mounted on the gun muzzle. A fast opening valve was used to release helium gas from the breech which formed into a blast wave and impacted instrumented targets in the test fixture. Blast attenuation of selected materials was determined through the measurement of stress data in front of and behind the target. Materials evaluated in this research include polyurethane foam from currently fielded US Army and Marine Corps helmets, polyurea 1000, and three hardnesses of Sorbothane (48, 58, and 70 durometer, Shore 00). Polyurea 1000 and 6061-T6 aluminum were used to calibrate the stress gauges.

  11. prfectBLAST: a platform-independent portable front end for the command terminal BLAST+ stand-alone suite.

    Science.gov (United States)

    Santiago-Sotelo, Perfecto; Ramirez-Prado, Jorge Humberto

    2012-11-01

    prfectBLAST is a multiplatform graphical user interface (GUI) for the stand-alone BLAST+ suite of applications. It allows researchers to do nucleotide or amino acid sequence similarity searches against public (or user-customized) databases that are locally stored. It does not require any dependencies or installation and can be used from a portable flash drive. prfectBLAST is implemented in Java version 6 (SUN) and runs on all platforms that support Java and for which National Center for Biotechnology Information has made available stand-alone BLAST executables, including MS Windows, Mac OS X, and Linux. It is free and open source software, made available under the GNU General Public License version 3 (GPLv3) and can be downloaded at www.cicy.mx/sitios/jramirez or http://code.google.com/p/prfectblast/.

  12. Numerical analysis of blast flow-field of baffle type muzzle brake

    Energy Technology Data Exchange (ETDEWEB)

    Kim, D.H. [Graduate School, Chungnam National University, Taejon (Korea); Ko, S. [Chungnam National University, Taejon (Korea)

    1998-11-01

    A three-dimensional unsteady, inviscid blast flow-field of a baffle type muzzle brake has been simulated by solving the Euler equation. The blast flow-field includes the effect of the free air blast, precursor blast flow and the propellant blast gas flow. Chimera grid scheme was used to generate 9 multi-block volume grids for the complex geometry. The evolution of the blast flow-field is presented by showing the contours of pressure, density and Mach number for certain time step. The comparison of the calculated and measured peak pressures on the surfaces of the muzzle brake is also presented. (author). 4 refs., 5 figs., 1 tab.

  13. Vacuum Energy and Inflation: 4. An Inflationary Universe

    Science.gov (United States)

    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…

  14. Vacuum system of SST-1 Tokamak

    International Nuclear Information System (INIS)

    Khan, Ziauddin; Pathan, Firozkhan; George, Siju; Semwal, Pratibha; Dhanani, Kalpesh; Paravastu, Yuvakiran; Thankey, Prashant; Ramesh, Gattu; Himabindu, Manthena; Pradhan, Subrata

    2013-01-01

    Highlights: ► Air leaks developed during ongoing SST-1 cooldown campaign were detected online using RGA. ► The presence of N 2 and O 2 gases with the ratio of their partial pressures with ∼3.81:1 confirmed the air leaks. ► Baking of SST-1 was done efficiently by flowing hot N 2 gas in C-channels welded on inner surfaces without any problem. ► In-house fabricated demountable bull nose couplers were demonstrated for high temperature and pressure applications. ► Cryopumping effect was observed when liquid helium cooled superconducting magnets reached below 63 K. -- Abstract: Vacuum chambers of Steady State Superconducting (SST-1) Tokamak comprises of the vacuum vessel and the cryostat. The plasma will be confined inside the vacuum vessel while the cryostat houses the superconducting magnet systems (TF and PF coils), LN 2 cooled thermal shields and hydraulics for these circuits. The vacuum vessel is an ultra-high (UHV) vacuum chamber while the cryostat is a high-vacuum (HV) chamber. In order to achieve UHV inside the vacuum vessel, it would be baked at 150 °C for longer duration. For this purpose, U-shaped baking channels are welded inside the vacuum vessel. The baking will be carried out by flowing hot nitrogen gas through these channels at 250 °C at 4.5 bar gauge pressure. During plasma operation, the pressure inside the vacuum vessel will be raised between 1.0 × 10 −4 mbar and 1.0 × 10 −5 mbar using piezoelectric valves and control system. An ultimate pressure of 4.78 × 10 −6 mbar is achieved inside the vacuum vessel after 100 h of pumping. The limitation is due to the development of few leaks of the order of 10 −5 mbar l/s at the critical locations of the vacuum vessel during baking which was confirmed with the presence of nitrogen gas and oxygen gas with the ratio of ∼3.81:1 indicating air leak. Similarly an ultimate vacuum of 2.24 × 10 −5 mbar is achieved inside the cryostat. Baking of the vacuum vessel up to 110 °C with ±10

  15. Vacuum system of SST-1 Tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Ziauddin, E-mail: ziauddin@ipr.res.in [Institute for Plasma Research, Near Indira Bridge, Bhat, Gandhinagar 382 428 (India); Pathan, Firozkhan; George, Siju; Semwal, Pratibha; Dhanani, Kalpesh; Paravastu, Yuvakiran; Thankey, Prashant; Ramesh, Gattu; Himabindu, Manthena; Pradhan, Subrata [Institute for Plasma Research, Near Indira Bridge, Bhat, Gandhinagar 382 428 (India)

    2013-10-15

    Highlights: ► Air leaks developed during ongoing SST-1 cooldown campaign were detected online using RGA. ► The presence of N{sub 2} and O{sub 2} gases with the ratio of their partial pressures with ∼3.81:1 confirmed the air leaks. ► Baking of SST-1 was done efficiently by flowing hot N{sub 2} gas in C-channels welded on inner surfaces without any problem. ► In-house fabricated demountable bull nose couplers were demonstrated for high temperature and pressure applications. ► Cryopumping effect was observed when liquid helium cooled superconducting magnets reached below 63 K. -- Abstract: Vacuum chambers of Steady State Superconducting (SST-1) Tokamak comprises of the vacuum vessel and the cryostat. The plasma will be confined inside the vacuum vessel while the cryostat houses the superconducting magnet systems (TF and PF coils), LN{sub 2} cooled thermal shields and hydraulics for these circuits. The vacuum vessel is an ultra-high (UHV) vacuum chamber while the cryostat is a high-vacuum (HV) chamber. In order to achieve UHV inside the vacuum vessel, it would be baked at 150 °C for longer duration. For this purpose, U-shaped baking channels are welded inside the vacuum vessel. The baking will be carried out by flowing hot nitrogen gas through these channels at 250 °C at 4.5 bar gauge pressure. During plasma operation, the pressure inside the vacuum vessel will be raised between 1.0 × 10{sup −4} mbar and 1.0 × 10{sup −5} mbar using piezoelectric valves and control system. An ultimate pressure of 4.78 × 10{sup −6} mbar is achieved inside the vacuum vessel after 100 h of pumping. The limitation is due to the development of few leaks of the order of 10{sup −5} mbar l/s at the critical locations of the vacuum vessel during baking which was confirmed with the presence of nitrogen gas and oxygen gas with the ratio of ∼3.81:1 indicating air leak. Similarly an ultimate vacuum of 2.24 × 10{sup −5} mbar is achieved inside the cryostat. Baking of the

  16. Design consideration on the synchrotron ultrahigh vacuum system

    International Nuclear Information System (INIS)

    Tsujikawa, H.; Chida, K.; Mizobuchi, A.; Miyahara, A.

    1982-01-01

    Ultrahigh vacuum production for the high-energy heavy-ion accelerator poses special problems concerning beam-gas molecule and beam-wall interactions. In this paper, summary of the TARN ultrahigh vacuum system and design criteria of the synchrotron ultrahigh vacuum system are presented. On-beam pressure of 4 x 10 -11 Torr is achieved in the TARN ultrahigh vacuum system, of which experiences through the construction and the operation are described and discussed. With emphasis on the application of newly developed technique in the fabrication of vacuum chamber and ultrahigh vacuum pump for the synchrotron ultrahigh vacuum system. (author)

  17. Full-scale testing of leakage of blast waves inside a partially vented room exposed to external air blast loading

    Science.gov (United States)

    Codina, R.; Ambrosini, D.

    2018-03-01

    For the last few decades, the effects of blast loading on structures have been studied by many researchers around the world. Explosions can be caused by events such as industrial accidents, military conflicts or terrorist attacks. Urban centers have been prone to various threats including car bombs, suicide attacks, and improvised explosive devices. Partially vented constructions subjected to external blast loading represent an important topic in protective engineering. The assessment of blast survivability inside structures and the development of design provisions with respect to internal elements require the study of the propagation and leakage of blast waves inside buildings. In this paper, full-scale tests are performed to study the effects of the leakage of blast waves inside a partially vented room that is subjected to different external blast loadings. The results obtained may be useful for proving the validity of different methods of calculation, both empirical and numerical. Moreover, the experimental results are compared with those computed using the empirical curves of the US Defense report/manual UFC 3-340. Finally, results of the dynamic response of the front masonry wall are presented in terms of accelerations and an iso-damage diagram.

  18. Design foundation of vacuum system for electron beam machine

    International Nuclear Information System (INIS)

    Darsono; Suprapto; Djasiman

    1999-01-01

    Vacuum system is a main part of electron beam Machine because (EBM) the electron can not be produced without this vacuum. Vacuum system consists of vacuum pump, connecting pipe, valve, and vacuum gauge. The design vacuum system of EBM, basis knowledge and technology of vacuum is needed. The paper describes types of vacuum pump, calculation of pipe conductance and pumping time of vacuum system then there are used as consideration of criteria to choose vacuum pump for EBM. From the result of study, it is concluded that for EBM of 500 keV/10 mA which is going to use for wood coating and with consideration of economic and technic factor it is better to use diffusion pump. (author)

  19. RELATION BETWEEN FUNCTION AND FORM IN VACUUM CLEANERS DESIGN

    Directory of Open Access Journals (Sweden)

    RADU Ștefan

    2015-11-01

    Full Text Available The paper analyses how robotic vacuum cleaner works, describing their cleaning capabilities and additional features. The paper illustrates advantages of using robotic vacuum cleaners that have intelligent programming and a vacuum cleaning system, the components of a robotic vacuum cleaner. The paper develops aspects concerning to create 2D scale models for the evaluation of specific features of the new components for a prototype robotic vacuum cleaner.

  20. Design of the ITER vacuum vessel

    International Nuclear Information System (INIS)

    Ioki, K.; Johnson, G.; Shimizu, K.; Williamson, D.

    1995-01-01

    The ITER vacuum vessel is a major safety barrier and must support electromagnetic loads during plasma disruptions and vertical displacement events (VDE) and withstand plausible accidents without losing confinement.The vacuum vessel has a double wall structure to provide structural and electrical continuity in the toroidal direction. The inner and outer shells and poloidal stiffening ribs between them are joined by welding, which gives the vessel the required mechanical strength. The space between the shells will be filled with steel balls and plate inserts to provide additional nuclear shielding. Water flowing in this space is required to remove nuclear heat deposition, which is 0.2-2.5% of the total fusion power. The minor and major radii of the tokamak are 3.9 m and 13 m respectively, and the overall height is 15 m. The total thickness of the vessel wall structure is 0.4-0.7 m.The inboard and outboard blanket segments are supported from the vacuum vessel. The support structure is required to withstand a large total vertical force of 200-300 MN due to VDE and to allow for differential thermal expansion.The first candidate for the vacuum vessel material is Inconel 625, due to its higher electric resistivity and higher yield strength, even at high temperatures. Type 316 stainless steel is also considered a vacuum vessel material candidate, owing to its large database and because it is supported by more conventional fabrication technology. (orig.)

  1. Compressed Air/Vacuum Transportation Techniques

    Science.gov (United States)

    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.

  2. Quantum vacuum energy in graphs and billiards

    International Nuclear Information System (INIS)

    Kaplan, L.

    2010-01-01

    The vacuum (Casimir) energy in quantum field theory is a problem relevant both to new nanotechnology devices and to dark energy in cosmology. The crucial question is the dependence of the energy on the system geometry. Despite much progress since the first prediction of the Casimir effect in 1948 and its subsequent experimental verification in simple geometries, even the sign of the force in nontrivial situations is still a matter of controversy. Mathematically, vacuum energy fits squarely into the spectral theory of second-order self-adjoint elliptic linear differential operators. Specifically one promising approach is based on the small-t asymptotics of the cylinder kernel e -t√(H) , where H is the self-adjoint operator under study. In contrast with the well-studied heat kernel e -tH , the cylinder kernel depends in a non-local way on the geometry of the problem. We discuss some results by the Louisiana-Oklahoma-Texas collaboration on vacuum energy in model systems, including quantum graphs and two-dimensional cavities. The results may shed light on general questions, including the relationship between vacuum energy and periodic or closed classical orbits, and the contribution to vacuum energy of boundaries, edges, and corners.

  3. Vacuum pumping for controlled thermonuclear reactors

    International Nuclear Information System (INIS)

    Watson, J.S.; Fisher, P.W.

    1976-01-01

    Thermonuclear reactors impose unique vacuum pumping problems involving very high pumping speeds, handling of hazardous materials (tritium), extreme cleanliness requirements, and quantitative recovery of pumped materials. Two principal pumping systems are required for a fusion reactor, a main vacuum system for evacuating the torus and a vacuum system for removing unaccelerated deuterium from neutral beam injectors. The first system must pump hydrogen isotopes and helium while the neutral beam system can operate by pumping only hydrogen isotopes (perhaps only deuterium). The most promising pumping techniques for both systems appear to be cryopumps, but different cryopumping techniques can be considered for each system. The main vacuum system will have to include cryosorption pumps cooled to 4.2 0 K to pump helium, but the unburned deuterium-tritium and other impurities could be pumped with cryocondensation panels (4.2 0 K) or cryosorption panels at higher temperatures. Since pumping speeds will be limited by conductance through the ducts and thermal shields, the pumping performance for both systems will be similar, and other factors such as refrigeration costs are likely to determine the choice. The vacuum pumping system for neutral beam injectors probably will not need to pump helium, and either condensation or higher temperature sorption pumps can be used

  4. Rising hopes for vacuum tube collectors

    Energy Technology Data Exchange (ETDEWEB)

    Godolphin, D.

    1982-06-01

    The performance, feasibility and use of vacuum tube solar collectors for domestic hot water (DHW) systems are discussed. An introduction to the design of vacuum tube collectors is presented and comparisons are made with flat plate collectors in terms of effectiveness in DHW applications and cost. The use of vacuum tube collectors is well established for high temperature use such as process heat and absorption cooling applications; there is considerable debate concerning their use in DHW and these arguments are presented. It is pointed out that the accepted standardized comparison test (ASHRAE 93-77) is apparently biased towards the flat plate collectors in direct comparisons of collector efficiencies. Recent developments among manufacturers with regard to vacuum tube collectors and their thinking (pro and con) are discussed in some detail. Breakage and other problems are pointed out although advocates look ahead to lower costs, higher efficiencies, and broader markets (particularly in DHW). It is concluded by some that flat plate collector technology has reached its peak and that vacuum tube collectors will be very prominent in the future. (MJJ)

  5. CERN Vacuum-System Activities during the Long Shutdown 1: The LHC Beam Vacuum

    CERN Document Server

    Baglin, V; Chiggiato, P; Jimenez, JM; Lanza, G

    2014-01-01

    After the Long Shutdown 1 (LS1) and the consolidation of the magnet bus bars, the CERN Large Hadron Collider (LHC) will operate with nominal beam parameters. Larger beam energy, beam intensities and luminosity are expected. Despite the very good performance of the beam vacuum system during the 2010-12 physics run (Run 1), some particular areas require attention for repair, consolidation and upgrade. Among the main activities, a large campaign aiming at the repair of the RF bridges of some vacuum modules is conducted. Moreover, consolidation of the cryogenic beam vacuum systems with burst disk for safety reasons is implemented. In addition, NEG cartridges, NEG coated inserts and new instruments for the vacuum system upgrade are installed. Besides these activities, repair, consolidation and upgrades of other beam equipment such as collimators, kickers and beam instrumentations are carried out. In this paper, the motivation and the description for such activities, together with the expected beam vacuum performa...

  6. Vacuum Bellows, Vacuum Piping, Cryogenic Break, and Copper Joint Failure Rate Estimates for ITER Design Use

    Energy Technology Data Exchange (ETDEWEB)

    L. C. Cadwallader

    2010-06-01

    The ITER international project design teams are working to produce an engineering design in preparation for construction of the International Thermonuclear Experimental Reactor (ITER) tokamak. During the course of this work, questions have arisen in regard to safety barriers and equipment reliability as important facets of system design. The vacuum system designers have asked several questions about the reliability of vacuum bellows and vacuum piping. The vessel design team has asked about the reliability of electrical breaks and copper-copper joints used in cryogenic piping. Research into operating experiences of similar equipment has been performed to determine representative failure rates for these components. The following chapters give the research results and the findings for vacuum system bellows, power plant stainless steel piping (amended to represent vacuum system piping), cryogenic system electrical insulating breaks, and copper joints.

  7. BLAST: Building energy simulation in Hong Kong

    Science.gov (United States)

    Fong, Sai-Keung

    1999-11-01

    The characteristics of energy use in buildings under local weather conditions were studied and evaluated using the energy simulation program BLAST-3.0. The parameters used in the energy simulation for the study and evaluation include the architectural features, different internal building heat load settings and weather data. In this study, mathematical equations and the associated coefficients useful to the industry were established. A technology for estimating energy use in buildings under local weather conditions was developed by using the results of this study. A weather data file of Typical Meteorological Years (TMY) has been compiled for building energy studies by analyzing and evaluating the weather of Hong Kong from the year 1979 to 1988. The weather data file TMY and the example weather years 1980 and 1988 were used by BLAST-3.0 to evaluate and study the energy use in different buildings. BLAST-3.0 was compared with other building energy simulation and approximation methods: Bin method and Degree Days method. Energy use in rectangular compartments of different volumes varying from 4,000 m3 to 40,000 m3 with different aspect ratios were analyzed. The use of energy in buildings with concrete roofs was compared with those with glass roofs at indoor temperature 21°C, 23°C and 25°C. Correlation relationships among building energy, space volume, monthly mean temperature and solar radiation were derived and investigated. The effects of space volume, monthly mean temperature and solar radiation on building energy were evaluated. The coefficients of the mathematical relationships between space volume and energy use in a building were computed and found satisfactory. The calculated coefficients can be used for quick estimation of energy use in buildings under similar situations. To study energy use in buildings, the cooling load per floor area against room volume was investigated. The case of an air-conditioned single compartment with 5 m ceiling height was

  8. 30 CFR 56.6404 - Separation of blasting circuits from power source.

    Science.gov (United States)

    2010-07-01

    ... LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL... when closed to fire the blast. (b) Lead wires shall not be connected to the blasting switch until the...

  9. Quality of computerized blast load simulation for non-linear dynamic ...

    African Journals Online (AJOL)

    Quality of computerized blast load simulation for non-linear dynamic response ... commercial software system and a special-purpose, blast-specific software product to ... depend both on the analysis model of choice and the stand-off distances.

  10. Thin walls in regions with vacuum energy

    Energy Technology Data Exchange (ETDEWEB)

    Garfinkle, D [Florida Univ., Gainesville, FL (USA). Dept. of Physics; Vuille, C [Embry-Riddle Aeronautical Univ., Prescott, AZ (USA). Dept. of Math/Physical Science

    1989-12-01

    The motion of a thin wall is treated in the case where the regions on either side of the wall have vacuum energy. This treatment generalises previous results involving domain walls in vacuum and also previous results involving the properties of false vacuum bubbles. The equation of state for a domain wall is{tau} = {sigma} where {tau} is the tension in the wall and {sigma} is the energy density. We consider the motion of a more general class of walls having equation of state {tau}{Gamma}{sigma} with 0{le}{Gamma}{le}1. Spherically symmetric and planar symmetric walls are examined. We also find the global structure of the wall spacetime. (author).

  11. Vacuum instability in scalar field theories

    International Nuclear Information System (INIS)

    McKane, A.J.

    1978-09-01

    Scalar field theories with an interaction of the form gphisup(N) have no stable vacuum state for some range of values of their coupling constant, g. This thesis reports calculations of vacuum instability in such theories. Using the idea that the tunnelling out of the vacuum state is described by the instanton solutions of the theory, the imaginary part of the vertex functions is calculated for the massless theory in the one-loop approximation, near the dimension dsub(c) = 2N/N-2, where the theory is just renormalisable. The calculation differs from previous treatments in that dimensional regularisation is used to control the ultra-violet divergences of the theory. In this way previous analytic calculations in conformally invariant field theories are extended to the case where the theory is almost conformally invariant, since it is now defined in dsub(c) - epsilon dimensions (epsilon > 0). (author)

  12. Quality Management of CERN Vacuum Controls

    CERN Document Server

    Antoniotti, F; Fortescue-Beck, E; Gama, J; Gomes, P; Le Roux, P; Pereira, H; Pigny, G

    2014-01-01

    The vacuum controls Section (TE-VSC-ICM) is in charge of the monitoring, maintenance and consolidation of the control systems of all accelerators and detectors in CERN; this represents 6 000 instruments distributed along 128 km of vacuum chambers, often of heterogeneous architectures and of diverse technical generations. In order to improve the efficiency of the services provided by ICM, to vacuum experts and to accelerator operators, a Quality Management Plan is being put into place. The first step was the standardization of the naming convention across different accelerators. The traceability of problems, requests, repairs, and other actions, has also been put into place (VTL). This was combined with the effort to identify each individual device by a coded label, and register it in a central database (MTF). Occurring in parallel, was the gathering of old documents and the centralization of information concerning architectures, procedures, equipment and settings (EDMS). To describe the topology of control c...

  13. Venturi vacuum systems for hypobaric chamber operations.

    Science.gov (United States)

    Robinson, R; Swaby, G; Sutton, T; Fife, C; Powell, M; Butler, B D

    1997-11-01

    Physiological studies of the effects of high altitude on man often require the use of a hypobaric chamber to simulate the reduced ambient pressures. Typical "altitude" chambers in use today require complex mechanical vacuum systems to evacuate the chamber air, either directly or via reservoir system. Use of these pumps adds to the cost of both chamber procurement and maintenance, and service of these pumps requires trained support personnel and regular upkeep. In this report we describe use of venturi vacuum pumps to perform the function of mechanical vacuum pumps for human and experimental altitude chamber operations. Advantages of the venturi pumps include their relatively low procurement cost, small size and light weight, ease of installation and plumbing, lack of moving parts, and independence from electrical power sources, fossil fuels and lubricants. Conversion of three hyperbaric chambers to combined hyper/hypobaric use is described.

  14. Vacuum instability in a random electric field

    International Nuclear Information System (INIS)

    Krive, I.V.; Pastur, L.A.

    1984-01-01

    The reaction of the vacuum on an intense spatially homogeneous random electric field is investigated. It is shown that a stochastic electric field always causes a breakdown of the boson vacuum, and the number of pairs of particles which are created by the electric field increases exponentially in time. For the choice of potential field in the form of a dichotomic random process we find in explicit form the dependence of the average number of pairs of particles on the time of the action of the source of the stochastic field. For the fermion vacuum the average number of pairs of particles which are created by the field in the lowest order of perturbation theory in the amplitude of the random field is independent of time

  15. Extremal vacuum black holes in higher dimensions

    International Nuclear Information System (INIS)

    Figueras, Pau; Lucietti, James; Rangamani, Mukund; Kunduri, Hari K.

    2008-01-01

    We consider extremal black hole solutions to the vacuum Einstein equations in dimensions greater than five. We prove that the near-horizon geometry of any such black hole must possess an SO(2,1) symmetry in a special case where one has an enhanced rotational symmetry group. We construct examples of vacuum near-horizon geometries using the extremal Myers-Perry black holes and boosted Myers-Perry strings. The latter lead to near-horizon geometries of black ring topology, which in odd spacetime dimensions have the correct number of rotational symmetries to describe an asymptotically flat black object. We argue that a subset of these correspond to the near-horizon limit of asymptotically flat extremal black rings. Using this identification we provide a conjecture for the exact 'phase diagram' of extremal vacuum black rings with a connected horizon in odd spacetime dimensions greater than five.

  16. Metastable electroweak vacuum. Implications for inflation

    Energy Technology Data Exchange (ETDEWEB)

    Lebedev, Oleg; Westphal, Alexander [DESY Theory Group, Hamburg (Germany)

    2012-10-15

    Within the Standard Model, the current Higgs and top quark data favor metastability of the electroweak vacuum, although the uncertainties are still significant. The true vacuum is many orders of magnitude deeper than ours and the barrier separating the two is tiny compared to the depth of the well. This raises a cosmological question: how did the Higgs field get trapped in the shallow minimum and why did it stay there during inflation? The Higgs initial conditions before inflation must be fine-tuned to about one part in 10{sup 8} in order for the Higgs field to end up in the right vacuum. In this note, we show that these problems can be resolved if there is a small positive coupling between the Higgs and the inflaton.

  17. Vacuum electron acceleration by coherent dipole radiation

    International Nuclear Information System (INIS)

    Troha, A.L.; Van Meter, J.R.; Landahl, E.C.; Alvis, R.M.; Hartemann, F.V.; Troha, A.L.; Van Meter, J.R.; Landahl, E.C.; Alvis, R.M.; Li, K.; Luhmann, N.C. Jr.; Hartemann, F.V.; Unterberg, Z.A.; Kerman, A.K.

    1999-01-01

    The validity of the concept of laser-driven vacuum acceleration has been questioned, based on an extrapolation of the well-known Lawson-Woodward theorem, which stipulates that plane electromagnetic waves cannot accelerate charged particles in vacuum. To formally demonstrate that electrons can indeed be accelerated in vacuum by focusing or diffracting electromagnetic waves, the interaction between a point charge and coherent dipole radiation is studied in detail. The corresponding four-potential exactly satisfies both Maxwell's equations and the Lorentz gauge condition everywhere, and is analytically tractable. It is found that in the far-field region, where the field distribution closely approximates that of a plane wave, we recover the Lawson-Woodward result, while net acceleration is obtained in the near-field region. The scaling of the energy gain with wave-front curvature and wave amplitude is studied systematically. copyright 1999 The American Physical Society

  18. Can vacuum decay in our universe?

    International Nuclear Information System (INIS)

    Wang Peng; Meng Xinhe

    2005-01-01

    We take a phenomenological approach to the study of the cosmological evolution of decaying vacuum cosmology (Λ(t)CDM) based on a simple assumption about the form of the modified matter expansion rate. In this framework, almost all current vacuum decaying models can be unified in a simple manner. We argue that the idea of letting vacuum decay to resolve the fine-tuning problem is inconsistent with cosmological observations. We also discuss some issues in confronting Λ(t)CDM with observation. Using the effective equation-of-state formalism, we indicate that Λ(t)CDM is a possible candidate for phantom cosmology. Moreover, confronted with a possible problem with the effective equation-of-state formalism, we construct the effective dark energy density. Finally, we discuss the evolution of linear perturbation

  19. Materials for high vacuum technology, an overview

    CERN Document Server

    Sgobba, Stefano

    2007-01-01

    In modern accelerators stringent requirements are placed on materials of vacuum systems. Their physical and mechanical properties, machinability, weldability or brazeability are key parameters. Adequate strength, ductility, magnetic properties at room as well as low temperatures are important factors for vacuum systems of accelerators working at cryogenic temperatures, such as the Large Hadron Collider (LHC) under construction at CERN. In addition, baking or activation of Non-Evaporable Getters (NEG) at high temperatures impose specific choices of material grades of suitable tensile and creep properties in a large temperature range. Today, stainless steels are the dominant materials of vacuum constructions. Their metallurgy is extensively treated. The reasons for specific requirements in terms of metallurgical processes are detailed, in view of obtaining adequate purity, inclusion cleanliness, and fineness of the microstructure. In many cases these requirements are crucial to guarantee the final leak tightnes...

  20. Metastable electroweak vacuum. Implications for inflation

    International Nuclear Information System (INIS)

    Lebedev, Oleg; Westphal, Alexander

    2012-10-01

    Within the Standard Model, the current Higgs and top quark data favor metastability of the electroweak vacuum, although the uncertainties are still significant. The true vacuum is many orders of magnitude deeper than ours and the barrier separating the two is tiny compared to the depth of the well. This raises a cosmological question: how did the Higgs field get trapped in the shallow minimum and why did it stay there during inflation? The Higgs initial conditions before inflation must be fine-tuned to about one part in 10 8 in order for the Higgs field to end up in the right vacuum. In this note, we show that these problems can be resolved if there is a small positive coupling between the Higgs and the inflaton.

  1. Primary Blast Injury Criteria for Animal/Human TBI Models using Field Validated Shock Tubes

    Science.gov (United States)

    2017-09-01

    acute hemorrhage characterized by partial filling of small groups of alveoli by blood . 240 kPa: Mild multifocal pools of acute hemorrhage which...Neurotrauma, Blast TBI, Primary blast brain injury, Blast overpressure, Blood -brain barrier, Neuroinflammation, Oxidative stress, Neuroproteomics 16...stress, neuroinflammation and BBB damage as a result of blast overpressure in the acute phase (0, 4 and 24 hours post-exposure). Our group

  2. Proceedings of the seventh annual symposium on explosives and blasting research

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Papers from this symposium dealt with the following topics: advanced primer designs, seismic effects of blasting, systems for velocity of detonation measurement and pressure measurement, toxic fumes from explosions, blast performance, blasting for rock fragmentation, computer-aided blast design, characteristics of liquid oxygen explosives, and correlations of performance of explosives with ground vibration, partitioning of energy, and firing time scatter effects. Papers have been indexed separately for inclusion on the data base

  3. Criteria for vacuum breakdown in rf cavities

    International Nuclear Information System (INIS)

    Peter, W.; Faehl, R.J.; Kadish, A.; Thode, L.E.

    1983-01-01

    A new high-voltage scaling based on Kilpatrick's criterion is presented that suggests that voltages more than twice the Kilpatrick limit can be obtained with identical initial conditions of vacuum and surface cleanliness. The calculations are based on the experimentally observed decrease in secondary electron emission with increasing ion-impact energy above 100 keV. A generalized secondary-emission package has been developed to simulate actual cavity dynamics in conjunction with our 2 1/2-dimensional fully electromagnetic particle-in-cell code CEMIT. The results are discussed with application to the suppression of vacuum breakdown in rf accelerator devices

  4. Noncommutative geometry and the standard model vacuum

    International Nuclear Information System (INIS)

    Barrett, John W.; Dawe Martins, Rachel A.

    2006-01-01

    The space of Dirac operators for the Connes-Chamseddine spectral action for the standard model of particle physics coupled to gravity is studied. The model is extended by including right-handed neutrino states, and the S 0 -reality axiom is not assumed. The possibility of allowing more general fluctuations than the inner fluctuations of the vacuum is proposed. The maximal case of all possible fluctuations is studied by considering the equations of motion for the vacuum. While there are interesting nontrivial vacua with Majorana-type mass terms for the leptons, the conclusion is that the equations are too restrictive to allow solutions with the standard model mass matrix

  5. Vacuum distillation/vapor filtration water recovery

    Science.gov (United States)

    Honegger, R. J.; Neveril, R. B.; Remus, G. A.

    1974-01-01

    The development and evaluation of a vacuum distillation/vapor filtration (VD/VF) water recovery system are considered. As a functional model, the system converts urine and condensates waste water from six men to potable water on a steady-state basis. The system is designed for 180-day operating durations and for function on the ground, on zero-g aircraft, and in orbit. Preparatory tasks are summarized for conducting low gravity tests of a vacuum distillation/vapor filtration system for recovering water from urine.

  6. Role of vacuum in food preservation

    International Nuclear Information System (INIS)

    Bongirwar, D.R.

    1997-01-01

    Considerable progress has been made in the processing of foods using operations viz. drying, evaporation, distillation, concentration, centrifugation, filtration, irradiation, freeze drying, osmotic drying etc. to get ready to eat food, convenience food, pre cooked dried food. Vacuum technology in direct or indirect way has played a vital role in carrying out these food processing operations. The role of vacuum in getting these processes developed and its use in the development of these high quality products with respect to colour, flavour, texture and other attributes has been highlighted along with process details. (author)

  7. Is the compactified vacuum semiclassically unstable

    International Nuclear Information System (INIS)

    Maeda, K.

    1987-01-01

    It is shown, by applying the positive-energy theorem, that the present vacuum (M 4 xK D ) in some higher-dimensional theories (e.g. the Candelas-Weinberg model) is stable against decay by quantum tunnelling without change of topology. Frieman and Kolb have found a quantum tunnelling instability of the present vacuum in the same models. But they did not take into account the gravitational effect, which is important and prevents the universe from decaying into the higher-dimensional de Sitter phase. (orig.)

  8. Strangeness condensation and ''clearing'' of the vacuum

    International Nuclear Information System (INIS)

    Brown, G.E.; Kubodera, Kuniharu; Rho, M.; State Univ. of New York, Stony Brook

    1987-01-01

    We show that a substantial amount of strange quark-antiquark pair condensates in the nucleon required by the πN sigma term implies that kaons could condense in nuclear matter at a density about three times that of normal nuclear matter. This phenomenon can be understood as the ''cleansing'' of qanti q condensates from the QCD vacuum by a dense nuclear matter, resulting in a (partial) restoration of the chiral symmetry explicitly broken in the vacuum. It is suggested that the condensation signals a new phase distinct from that of quark plasma and that of ordinary dense hadronic matter. (orig.)

  9. The fate of the Higgs vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Burda, Philipp [Racah Institute of Physics, Hebrew University,Jerusalem 91904 (Israel); Centre for Particle Theory, Durham University,South Road, Durham, DH1 3LE (United Kingdom); Gregory, Ruth [Centre for Particle Theory, Durham University,South Road, Durham, DH1 3LE (United Kingdom); Perimeter Institute,31 Caroline Street North, Waterloo, ON, N2L 2Y5 (Canada); Moss, Ian G. [School of Mathematics and Statistics, Newcastle University,Newcastle Upon Tyne, NE1 7RU (United Kingdom)

    2016-06-06

    We have recently suggested that tiny black holes can act as nucleation seeds for the decay of the metastable Higgs vacuum. Previous results applied only to the nucleation of thin-wall bubbles, and covered a very small region of parameter space. This paper considers bubbles of arbitrary profile and reaches the same conclusion: black holes seed rapid vacuum decay. Seeded and unseeded nucleation rates are compared, and the gravitational back reaction of the bubbles is taken into account. The evolution of the bubble interior is described for the unseeded nucleation. Results are presented for the renormalisation group improved Standard Model Higgs potential, and a simple effective model representing new physics.

  10. The fate of the Higgs vacuum

    International Nuclear Information System (INIS)

    Burda, Philipp; Gregory, Ruth; Moss, Ian G.

    2016-01-01

    We have recently suggested that tiny black holes can act as nucleation seeds for the decay of the metastable Higgs vacuum. Previous results applied only to the nucleation of thin-wall bubbles, and covered a very small region of parameter space. This paper considers bubbles of arbitrary profile and reaches the same conclusion: black holes seed rapid vacuum decay. Seeded and unseeded nucleation rates are compared, and the gravitational back reaction of the bubbles is taken into account. The evolution of the bubble interior is described for the unseeded nucleation. Results are presented for the renormalisation group improved Standard Model Higgs potential, and a simple effective model representing new physics.

  11. Higgs vacuum stability and modified chaotic inflation

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Abhijit Kumar, E-mail: abhijit.saha@iitg.ernet.in; Sil, Arunansu, E-mail: asil@iitg.ernet.in

    2017-02-10

    The issue of electroweak vacuum stability is studied in presence of a scalar field which participates in modifying the minimal chaotic inflation model. It is shown that the threshold effect on the Higgs quartic coupling originating from the Higgs–inflaton sector interaction can essentially make the electroweak vacuum stable up to the Planck scale. On the other hand we observe that the new physics parameters in this combined framework are enough to provide deviation from the minimal chaotic inflation predictions so as to keep it consistent with recent observation by Planck 2015.

  12. Instability of the Kaluza-Klein vacuum

    International Nuclear Information System (INIS)

    Witten, E.

    1982-01-01

    It is argued that the ground state of the Kaluza-Klein unified theory is unstable against a process of semiclassical barrier penetration. This is related to the fact that the positive energy conjecture does not hold for the Kaluza-Klein theory; an explicit counter-example is given. The reasoning presented here assumes that in general relativity one should include manifolds of non-vacuum topology. It is argued that the existence of elementary fermions (not present in the original Kaluza-Klein theory) would stabilize the Kaluza-Klein vacuum. (orig.)

  13. A Foundation for Vacuuming Temporal Databases

    DEFF Research Database (Denmark)

    Skyt, Janne; Jensen, Christian Søndergaard; Mark, L.

    2003-01-01

    A wide range of real-world database applications, including financial and medical applications, are faced with accountability and traceability requirements. These requirements lead to the replacement of the usual update-in-place policy by an append-only policy that retain all previous states...... only received little attention. Such vacuuming is called for by, e.g., the laws of many countries and the policies of many businesses. Although necessary, with vacuuming, the database’s perfect recollection of the past may be compromised via, e.g., selective removal of records pertaining to past states...

  14. Vacuum pumping by the halo plasma

    International Nuclear Information System (INIS)

    Barr, W.L.

    1985-01-01

    An estimate is made of the effective vacuum pumping speed of the halo plasma in a tandem mirror fusion reactor, and it is shown that, if the electron temperature and line density are great enough, the halo can be a very good vacuum pump. One can probably obtain the required density by recycling the ions at the halo dumps. An array of small venting ports in the dump plates allows local variation of the recycle fraction and local removal of the gas at a conveniently high pressure. This vented-port concept could introduce more flexibility in the design of pumped limiters for tokamaks

  15. Evaluating operational vacuum for landfill biogas extraction.

    Science.gov (United States)

    Fabbricino, Massimiliano

    2007-01-01

    This manuscript proposes a practical methodology for estimating the operational vacuum for landfill biogas extraction from municipal landfills. The procedure is based on two sub-models which simulate landfill gas production from organic waste decomposition and distribution of gas pressure and gas movement induced by suction at a blower station. The two models are coupled in a single mass balance equation, obtaining a relationship between the operational vacuum and the amount of landfill gas that can be extracted from an assigned system of vertical wells. To better illustrate the procedure, it is applied to a case study, where a good agreement between simulated and measured data, within +/- 30%, is obtained.

  16. Internal motion in high vacuum systems

    Science.gov (United States)

    Frank, J. M.

    Three transfer and positioning mechanisms have been developed for the non-air exposed, multistep processing of components in vacuum chambers. The functions to be performed in all of the systems include ultraviolet/ozone cleaning, vacuum baking, deposition of thin films, and thermocompression sealing of the enclosures. Precise positioning of the components is required during the evaporation and sealing processes. The three methods of transporting and positioning the components were developed to accommodate the design criteria and goals of each individual system. The design philosophy, goals, and operation of the three mechanisms are discussed.

  17. Structural Analysis of the NCSX Vacuum Vessel

    International Nuclear Information System (INIS)

    Fred Dahlgren; Art Brooks; Paul Goranson; Mike Cole; Peter Titus

    2004-01-01

    The NCSX (National Compact Stellarator Experiment) vacuum vessel has a rather unique shape being very closely coupled topologically to the three-fold stellarator symmetry of the plasma it contains. This shape does not permit the use of the common forms of pressure vessel analysis and necessitates the reliance on finite element analysis. The current paper describes the NCSX vacuum vessel stress analysis including external pressure, thermal, and electro-magnetic loading from internal plasma disruptions and bakeout temperatures of up to 400 degrees centigrade. Buckling and dynamic loading conditions are also considered

  18. Bingham Sealing and Application in Vacuum Clamping

    Science.gov (United States)

    Yao, S. M.; Teo, Wee Kin; Geng, Zunmin; Turner, Sam; Ridgway, Keith

    2011-12-01

    Vacuum clamping is extensively used in shell machining. In this paper a Bingham Sealing (BS) is presented and formulized based on Bingham plastic performance. The sealing capability of BS is evaluated in various cases. A new Bingham plastic is developed and the yield stress is measured. The performances of "O"ring sealing and BS with the developed Bingham plastic are compared to the static experiment. In this experiment the same vacuum is achieved and the distortion of the blade with BS is better than that with "O" ring sealing.

  19. Bingham Sealing and Application in Vacuum Clamping

    International Nuclear Information System (INIS)

    Yao, S M; Teo, Wee Kin; Geng Zunmin; Turner, Sam; Ridgway, Keith

    2011-01-01

    Vacuum clamping is extensively used in shell machining. In this paper a Bingham Sealing (BS) is presented and formulized based on Bingham plastic performance. The sealing capability of BS is evaluated in various cases. A new Bingham plastic is developed and the yield stress is measured. The performances of Or ing sealing and BS with the developed Bingham plastic are compared to the static experiment. In this experiment the same vacuum is achieved and the distortion of the blade with BS is better than that with 'O' ring sealing.

  20. Vacuum stability in neutrinophilic Higgs doublet model

    International Nuclear Information System (INIS)

    Haba, Naoyuki; Horita, Tomohiro

    2011-01-01

    A neutrinophilic Higgs model has tiny vacuum expectation value (VEV), which can naturally explain tiny masses of neutrinos. There is a large energy scale hierarchy between a VEV of the neutrinophilic Higgs doublet and that of usual standard model-like Higgs doublet. In this Letter we at first analyze vacuum structures of Higgs potential in both supersymmetry (SUSY) and non-SUSY neutrinophilic Higgs models, and next investigate a stability of this VEV hierarchy against radiative corrections. We will show that the VEV hierarchy is stable against radiative corrections in both Dirac neutrino and Majorana neutrino scenarios in both SUSY and non-SUSY neutrinophilic Higgs doublet models.