Systemic toxicity of dermally applied crude oils in rats

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

Feuston, M.H.; Mackerer, C.R.; Schreiner, C.A.

1997-12-31

Two crude oils, differing in viscosity (V) and nitrogen (N) and sulfur (S) content, were evaluated for systemic toxicity, In the Crude I (low V, low N, low S) study, the material was applied to the clipped backs of rats at dose levels of 0, 30, 125, and 500 mg/kg. In the Crude II (high V, high N, moderate S) study, the oil was applied similarly at the same dose levels. The crude oils were applied for 13 wk, 5 d/wk. Exposure sites were not occluded. Mean body weight gain (wk 1-14) was significantly reduced in male rats exposed tomore » Crude II; body weight gain of all other animals was not adversely affected by treatment. An increase in absolute (A) and relative (R) liver weights and a decrease in A and R thymus weights were observed in male and female rats exposed to Crude II at 500 mg/kg; only liver weights (A and R) were adversely affected in male and female rats exposed to Crude I. In general, there was no consistent pattern of toxicity for serum chemistry endpoints; however, more parameters were adversely affected in Crude II-exposed female rats than in the other exposed groups. A consistent pattern of toxicity for hematology endpoints was observed among male rats exposed to Crude I and male and female rats exposed to Crude II. Parameters affected included: Crudes I and II, red blood cell count, hemoglobin, and hematocrit, Crude II, platelet count. Microscopic evaluation of tissues revealed the following treatment-related findings: Crude I, treated skin, thymus, and thyroid; Crude II, bone marrow, treated skin, thymus, and thyroid. The LOEL (lowest observable effect level) for skin irritation and systemic toxicity (based on marginal effects on the thyroid) for both crude oils was 30 mg/kg; effects were more numerous and more pronounced in animals exposed to Crude II. Systemic effects are probably related to concentrations of polycyclic aromatic compounds (PAC) found in crude oil.« less

18. VIEW OF CRUDE ORE BINS FROM WEST. WEST CRUDE ...

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

18. VIEW OF CRUDE ORE BINS FROM WEST. WEST CRUDE ORE BIN AND TRESTLE FROM TWO JOHNS TRAMLINE TO SOUTH, CRUDE ORE BIN IN FOREGROUND. MACHINE SHOP IN BACKGROUND. THE TRAM TO PORTLAND PASSED TO NORTH OF MACHINE SHOP. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Methods of cracking a crude product to produce additional crude products

DOEpatents

Mo, Weijian [Sugar Land, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX; Nair, Vijay [Katy, TX

2009-09-08

A method for producing a crude product is disclosed. Formation fluid is produced from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. The liquid stream is fractionated to produce one or more crude products. At least one of the crude products has a boiling range distribution from 38.degree. C. and 343.degree. C. as determined by ASTM Method D5307. The crude product having the boiling range distribution from 38.degree. C. and 343.degree. C. is catalytically cracked to produce one or more additional crude products. At least one of the additional crude products is a second gas stream. The second gas stream has a boiling point of at most 38.degree. C. at 0.101 MPa.

Enhanced crude oil biodegradation in soil via biostimulation.

PubMed

Al-Saleh, Esmaeil; Hassan, Ali

2016-08-02

Research on feasible methods for the enhancement of bioremediation in soil contaminated by crude oil is vital in oil-exporting countries such as Kuwait, where crude oil is a major pollutant and the environment is hostile to biodegradation. This study investigated the possibility of enhancing crude oil bioremediation by supplementing soil with cost-effective organic materials derived from two widespread locally grown trees, Conocarpus and Tamarix. Amendments in soils increased the counts of soil microbiota by up to 98% and enhanced their activity by up to 95.5%. The increase in the biodegradation of crude oil (75%) and high levels of alkB expression substantiated the efficiency of the proposed amendment technology for the bioremediation of hydrocarbon-contaminated sites. The identification of crude-oil-degrading bacteria revealed the dominance of the genus Microbacterium (39.6%), Sphingopyxis soli (19.3%), and Bordetella petrii (19.6%) in unamended, Conocarpus-amended, and Tamarix-amended contaminated soils, respectively. Although soil amendments favored the growth of Gram-negative bacteria and reduced bacterial diversity, the structures of bacterial communities were not significantly altered.

Apparatus For Metal/Inert-Gas Welding In Vacuum

NASA Technical Reports Server (NTRS)

Stocks, C. O.

1994-01-01

Metal/inert-gas welding-torch assembly operates in vacuum. Plasma generated in interior chamber and focused onto workpiece in vacuum. Pinch rollers feed wire to weld puddle. Controlled flow of plasma reduces dispersal in vacuum, preventing extinction.

A laboratory study of particulate and gaseous emissions from crude oil and crude oil-dispersant contaminated seawater due to breaking waves

NASA Astrophysics Data System (ADS)

Afshar-Mohajer, Nima; Li, Cheng; Rule, Ana M.; Katz, Joseph; Koehler, Kirsten

2018-04-01

Crude oil spill incidents occur frequently causing a verity of occupational, ecological and environmental problems. Dispersants are applied to enhance the dispersion rate of crude oil slicks into the water column. In this study, the aerosol size distribution from 10 nm to 20 μm, total particle-bound aromatic hydrocarbons (pPAH) and volatile organic compounds (VOCs) are measured in a 6 x 0.3 x 0.6 m tank as plunging breaking waves entrain oil slicks. The experiments are performed for seawater with slicks of crude oil, crude oil-dispersant mixture and dispersant only. The measurements investigate the effects of wave energy and slick properties on the temporal evolution of the emissions. The total number concentrations of particles originating from the oil-dispersant mixture are 1-2 orders of magnitude higher than those of crude oil across the entire nano-scale range, reaching 100x for 20 nm particles. Conversely, the differences in concentration are small in the micron range. The average concentrations of pPAH are variable but similar (150-270 ng/m3). The VOC concentrations for crude oil-dispersant mixtures are 2-3 times lower than those of crude oil, presumably due to the surfactant effect on mass diffusion. The drastic increase in ultrafine particle concentrations may raise concerns about effects of inhalation by cleanup workers and downstream communities though VOC emissions reduce. Findings through this study provide insight into how the spray of dispersant may change the ratio of airborne particulate matter and VOC emissions from seawater due to natural processes.

Microbial ecology of a crude oil contaminated aquifer

USGS Publications Warehouse

Bekins, B.A.; Cozzarelli, I.M.; Warren, E.; Godsy, E.M.

2002-01-01

Detailed microbial analyses of a glacial outwash aquifer contaminated by crude oil provide insights into the pattern of microbial succession from iron reducing to methanogenic in the anaerobic portion of the contaminant plume. We analysed sediments from this area for populations of aerobes, iron reducers, fermenters and methanogens, using the most probable number method. On the basis of the microbial data the anaerobic area can be divided into distinct physiological zones dominated by either iron-reducers or a consortium of fermenters and methanogens. Chemistry and permeability data show that methanogenic conditions develop first in areas of high hydrocarbon flux. Thus, we find methanogens both in high permeability horizons and also where separate-phase crude oil is present in either the saturated or unsaturated zone. Microbial numbers peak at the top of the separate-phase oil suggesting that growth is most rapid in locations with access to both hydrocarbons and nutrients infiltrating from the surface.

Vacuum force

NASA Astrophysics Data System (ADS)

Han, Yongquan

2015-03-01

To study on vacuum force, we must clear what is vacuum, vacuum is a space do not have any air and also ray. There is not exist an absolute the vacuum of space. The vacuum of space is relative, so that the vacuum force is relative. There is a certain that vacuum vacuum space exists. In fact, the vacuum space is relative, if the two spaces compared to the existence of relative vacuum, there must exist a vacuum force, and the direction of the vacuum force point to the vacuum region. Any object rotates and radiates. Rotate bend radiate- centripetal, gravity produced, relative gravity; non gravity is the vacuum force. Gravity is centripetal, is a trend that the objects who attracted wants to Centripetal, or have been do Centripetal movement. Any object moves, so gravity makes the object curve movement, that is to say, the radiation range curve movement must be in the gravitational objects, gravity must be existed in non vacuum region, and make the object who is in the region of do curve movement (for example: The earth moves around the sun), or final attracted in the form gravitational objects, and keep relatively static with attract object. (for example: objects on the earth moves but can't reach the first cosmic speed).

19. VIEW OF CRUDE ORE BINS FROM EAST. EAST CRUDE ...

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

19. VIEW OF CRUDE ORE BINS FROM EAST. EAST CRUDE ORE BIN IN FOREGROUND WITH DISCHARGE TO GRIZZLY AT BOTTOM OF VIEW. CONCRETE RETAINING WALL TO LEFT (SOUTH) AND BOTTOM (EAST EDGE OF EAST BIN). - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Vacuum deposition and curing of liquid monomers

DOEpatents

Affinito, J.D.

1993-11-09

The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of standard polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.

Vacuum deposition and curing of liquid monomers

DOEpatents

Affinito, J.D.

1995-03-07

The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of ``standard`` polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal or oxide may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.

Vacuum deposition and curing of liquid monomers

DOEpatents

Affinito, John D.

1993-01-01

The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of "standard" polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.

Vacuum deposition and curing of liquid monomers

DOEpatents

Affinito, John D.

1995-01-01

The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of "standard" polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal or oxide may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.

Crude cacao Theobroma cacao extract reduces mutagenicity induced by benzo[a]pyrene through inhibition of CYP1A activity in vitro.

PubMed

Ohno, Marumi; Sakamoto, Kentaro Q; Ishizuka, Mayumi; Fujita, Shoichi

2009-08-01

Polyphenols have been shown to have potent antioxidant activity, and therefore, food containing polyphenols is expected to contribute to the prevention of cancer. However, food contains not only polyphenols but also various other constituents. We used the Ames test to investigate the effects of crude extracts of whole cacao products, which are known to be rich in polyphenols, on the mutagenicity of benzo[a]pyrene (B[a]P) in Salmonella typhimurium strain TA 98 and tert-butyl hydroperoxide (t-BuOOH) in S. typhimurium strain TA 102. B[a]P induces mutagenicity by metabolic activation and t-BuOOH induces it by generation of free radicals. While white chocolate did not modulate the numbers of revertant colonies produced by B[a]P treatment, milk chocolate and cacao powder extracts did. On the other hand, surprisingly, none of the cacao products tested affected the number of revertant colonies when t-BuOOH was used as the mutagen. At maximum concentration (13.25 mg cacao powder/ml), the crude cacao powder extract reduced ethoxyresorufin O-deethylase activity to 17.4% of the control, suggesting that whole cacao products inhibit cytochrome P450 (CYP) 1A activity. In conclusion, inhibition of CYP1A activity by cacao products may prevent DNA damage by reducing metabolic activation of carcinogens. Copyright 2009 John Wiley & Sons, Ltd.

Electric Propulsion Laboratory Vacuum Chamber

NASA Image and Video Library

1964-06-21

Engineer Paul Reader and his colleagues take environmental measurements during testing of a 20-inch diameter ion engine in a vacuum tank at the Electric Propulsion Laboratory (EPL). Researchers at the Lewis Research Center were investigating the use of a permanent-magnet circuit to create the magnetic field required power electron bombardment ion engines. Typical ion engines use a solenoid coil to create this magnetic field. It was thought that the substitution of a permanent magnet would create a comparable magnetic field with a lower weight. Testing of the magnet system in the EPL vacuum tanks revealed no significant operational problems. Reader found the weight of the two systems was similar, but that the thruster’s efficiency increased with the magnet. The EPL contained a series of large vacuum tanks that could be used to simulate conditions in space. Large vacuum pumps reduced the internal air pressure, and a refrigeration system created the cryogenic temperatures found in space.

19 CFR 10.179 - Canadian crude petroleum subject to a commercial exchange agreement between United States and...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Canadian crude petroleum subject to a commercial... CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions Canadian Crude Petroleum § 10.179 Canadian crude petroleum subject to a commercial exchange agreement between United States and Canadian...

19 CFR 10.179 - Canadian crude petroleum subject to a commercial exchange agreement between United States and...

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 1 2011-04-01 2011-04-01 false Canadian crude petroleum subject to a commercial... CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions Canadian Crude Petroleum § 10.179 Canadian crude petroleum subject to a commercial exchange agreement between United States and Canadian...

Vacuum distillation residue upgrading by an indigenous bacillus cereus

PubMed Central

2013-01-01

Background Biological processing of heavy fractions of crude oils offers less severe process conditions and higher selectivity for refining. Biochemical Processes are expected to be low demand energy processes and certainly ecofriendly. Results A strain of biosurfactant producing bacterium was isolated from an oil contaminated soil at Tehran refinery distillation unit. Based on selected phenotypic and genotypic characteristic including morphology, biochemical proprety, and 16 SrRNA sequencing identified as a novel strain of Bacillus cereus (JQ178332). This bacterium endures a wide range of pH, salinity and temperature. This specific strain utilizes both paraffin and anthracene as samples of aliphatic and polycyclic aromatic hydrocarbons. The ability of this bacterium to acquire all its energy and chemical requirements from Vacuum Distillation Residue (VR), as a net sample of problematic hydrocarbons in refineries, was studied. SARA test ASTM D4124-01 revealed 65.5% decrease in asphaltenic, 22.1% in aliphatics and 30.3% in Aromatics content of the VR in MSM medium. Further results with 0.9% saline showed 55% decrease in asphaltene content and 2.1% Aromatics respectively. Conclusion Remarkable abilities of this microorganism propose its application in an ecofriendly technology to upgrade heavy crude oils. PMID:24499629

Vacuum distillation residue upgrading by an indigenous Bacillus cereus.

PubMed

Tabatabaee, Mitra Sadat; Mazaheri Assadi, Mahnaz

2013-07-16

Biological processing of heavy fractions of crude oils offers less severe process conditions and higher selectivity for refining. Biochemical Processes are expected to be low demand energy processes and certainly ecofriendly. A strain of biosurfactant producing bacterium was isolated from an oil contaminated soil at Tehran refinery distillation unit. Based on selected phenotypic and genotypic characteristic including morphology, biochemical proprety, and 16 SrRNA sequencing identified as a novel strain of Bacillus cereus (JQ178332). This bacterium endures a wide range of pH, salinity and temperature. This specific strain utilizes both paraffin and anthracene as samples of aliphatic and polycyclic aromatic hydrocarbons. The ability of this bacterium to acquire all its energy and chemical requirements from Vacuum Distillation Residue (VR), as a net sample of problematic hydrocarbons in refineries, was studied. SARA test ASTM D4124-01 revealed 65.5% decrease in asphaltenic, 22.1% in aliphatics and 30.3% in Aromatics content of the VR in MSM medium. Further results with 0.9% saline showed 55% decrease in asphaltene content and 2.1% Aromatics respectively. Remarkable abilities of this microorganism propose its application in an ecofriendly technology to upgrade heavy crude oils.

Methods of analyzing crude oil

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

Cooks, Robert Graham; Jjunju, Fred Paul Mark; Li, Anyin

The invention generally relates to methods of analyzing crude oil. In certain embodiments, methods of the invention involve obtaining a crude oil sample, and subjecting the crude oil sample to mass spectrometry analysis. In certain embodiments, the method is performed without any sample pre-purification steps.

Identification of crude-oil components and microorganisms that cause souring under anaerobic conditions.

PubMed

Hasegawa, R; Toyama, K; Miyanaga, K; Tanji, Y

2014-02-01

Oil souring has important implications with respect to energy resources. Understanding the physiology of the microorganisms that play a role and the biological mechanisms are both important for the maintenance of infrastructure and mitigation of corrosion processes. The objective of this study was to identify crude-oil components and microorganisms in oil-field water that contribute to crude-oil souring. To identify the crude-oil components and microorganisms that are responsible for anaerobic souring in oil reservoirs, biological conversion of crude-oil components under anaerobic conditions was investigated. Microorganisms in oil field water in Akita, Japan degraded alkanes and aromatics to volatile fatty acids (VFAs) under anaerobic conditions, and fermenting bacteria such as Fusibacter sp. were involved in VFA production. Aromatics such as toluene and ethylbenzene were degraded by sulfate-reducing bacteria (Desulfotignum sp.) via the fumarate-addition pathway and not only degradation of VFA but also degradation of aromatics by sulfate-reducing bacteria was the cause of souring. Naphthenic acid and 2,4-xylenol were not converted.

Optimization of a vacuum chamber for vibration measurements.

PubMed

Danyluk, Mike; Dhingra, Anoop

2011-10-01

A 200 °C high vacuum chamber has been built to improve vibration measurement sensitivity. The optimized design addresses two significant issues: (i) vibration measurements under high vacuum conditions and (ii) use of design optimization tools to reduce operating costs. A test rig consisting of a cylindrical vessel with one access port has been constructed with a welded-bellows assembly used to seal the vessel and enable vibration measurements in high vacuum that are comparable with measurements in air. The welded-bellows assembly provides a force transmissibility of 0.1 or better at 15 Hz excitation under high vacuum conditions. Numerical results based on design optimization of a larger diameter chamber are presented. The general constraints on the new design include material yield stress, chamber first natural frequency, vibration isolation performance, and forced convection heat transfer capabilities over the exterior of the vessel access ports. Operating costs of the new chamber are reduced by 50% compared to a preexisting chamber of similar size and function.

Improving performance of electrostatic heater-theaters for light crude doped heavy crude; A case study

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

Bhattacharya, A.; Ray, S.; Rai, R.

1995-12-31

Crude oil treatment systems for heavy oil assume paramount importance due to the difficult nature of emulsions formed and presence of water in the form of small droplets. With the aging of heavy oil fields, operating under active water drive, water content in the emulsion produced increases substantially. This has a direct impact on heater-treater performance and treated crude quality. A typical problem is discussed in this paper where the gradual increase in emulsion production over a period of time in heavy oil belts of ONGC have affected the electrostatic heater-treater performance, treating light crude doped heavy crude, resulting inmore » increased BS&W (basic sediments and water) in the treated crude. Critical levels of water cut in both heavy and light crudes have been identified beyond which the existing emulsion treating system becomes ineffective. Analysis have also been carried out to identify optimum mixing proportion which result in the most effective demulsification.« less

Rhamnolipid produced by Pseudomonas aeruginosa USM-AR2 facilitates crude oil distillation.

PubMed

Asshifa Md Noh, Nur; Al-Ashraf Abdullah, Amirul; Nasir Mohamad Ibrahim, Mohamad; Ramli Mohd Yahya, Ahmad

2012-01-01

A biosurfactant-producing and hydrocarbon-utilizing bacterium, Pseudomonas aeruginosa USM-AR2, was used to assist conventional distillation. Batch cultivation in a bioreactor gave a biomass of 9.4 g L(-1) and rhamnolipid concentration of 2.4 g L(-1) achieved after 72 h. Biosurfactant activity (rhamnolipid) was detected by the orcinol assay, emulsification index and drop collapse test. Pretreatment of crude oil TK-1 and AG-2 with a culture of P. aeruginosa USM-AR2 that contains rhamnolipid was proven to facilitate the distillation process by reducing the duration without reducing the quality of petroleum distillate. It showed a potential in reducing the duration of the distillation process, with at least 2- to 3-fold decreases in distillation time. This is supported by GC-MS analysis of the distillate where there was no difference between compounds detected in distillate obtained from treated or untreated crude oil. Calorimetric tests showed the calorie value of the distillate remained the same with or without treatment. These two factors confirmed that the quality of the distillate was not compromised and the incubation process by the microbial culture did not over-degrade the oil. The rhamnolipid produced by this culture was the main factor that enhanced the distillation performance, which is related to the emulsification of hydrocarbon chains in the crude oil. This biotreatment may play an important role to improve the existing conventional refinery and distillation process. Reducing the distillation times by pretreating the crude oil with a natural biosynthetic product translates to energy and cost savings in producing petroleum products.

U.S. Crude Oil and Natural Gas Proved Reserves

EIA Publications

2016-01-01

U.S. oil and natural gas proved reserves declined in 2015 due to lower prices. U.S. crude oil and lease condensate proved reserves declined 4.7 billion barrels (11.8%) from their year-end 2014 level to 35.2 billion barrels at year-end 2015, according to U.S. Crude Oil and Natural Gas Proved Reserves, Year-end 2015, released today by the U.S. Energy Information Administration. U.S natural gas proved reserves decreased 64.5 trillion cubic feet, a 16.6% decline, reducing the U.S. total to 324.3 Tcf at year-end 2015.

Vacuum-assisted drainage in cardiopulmonary bypass: advantages and disadvantages

PubMed Central

de Carvalho Filho, Élio Barreto; Marson, Fernando Augusto de Lima; da Costa, Loredana Nilkenes Gomes; Antunes, Nilson

2014-01-01

Systematic review of vacuum assisted drainage in cardiopulmonary bypass, demonstrating its advantages and disadvantages, by case reports and evidence about its effects on microcirculation. We conducted a systematic search on the period 1997-2012, in the databases PubMed, Medline, Lilacs and SciELO. Of the 70 selected articles, 26 were included in the review. Although the vacuum assisted drainage has significant potential for complications and requires appropriate technology and professionalism, prevailed in literature reviewed the concept that vacuum assisted drainage contributed in reducing the rate of transfusions, hemodilutions, better operative field, no significant increase in hemolysis, reduced complications surgical, use of lower prime and of smaller diameter cannulas. PMID:25140478

Vacuum-assisted drainage in cardiopulmonary bypass: advantages and disadvantages.

PubMed

Carvalho Filho, Elio Barreto de; Marson, Fernando Augusto de Lima; Costa, Loredana Nilkenes Gomes da; Antunes, Nilson

2014-01-01

Systematic review of vacuum assisted drainage in cardiopulmonary bypass, demonstrating its advantages and disadvantages, by case reports and evidence about its effects on microcirculation. We conducted a systematic search on the period 1997-2012, in the databases PubMed, Medline, Lilacs and SciELO. Of the 70 selected articles, 26 were included in the review. Although the vacuum assisted drainage has significant potential for complications and requires appropriate technology and professionalism, prevailed in literature reviewed the concept that vacuum assisted drainage contributed in reducing the rate of transfusions, hemodilutions, better operative field, no significant increase in hemolysis, reduced complications surgical, use of lower prime and of smaller diameter cannulas.

Vacuum-Induction, Vacuum-Arc, and Air-Induction Melting of a Complex Heat-Resistant Alloy

NASA Technical Reports Server (NTRS)

Decker, R. F.; Rowe, John P.; Freeman, J. W.

1959-01-01

The relative hot-workability and creep-rupture properties at 1600 F of a complex 55Ni-20Cr-15Co-4Mo-3Ti-3Al alloy were evaluated for vacuum-induction, vacuum-arc, and air-induction melting. A limited study of the role of oxygen and nitrogen and the structural effects in the alloy associated with the melting process was carried out. The results showed that the level of boron and/or zirconium was far more influential on properties than the melting method. Vacuum melting did reduce corner cracking and improve surface during hot-rolling. It also resulted in more uniform properties within heats. The creep-rupture properties were slightly superior in vacuum heats at low boron plus zirconium or in heats with zirconium. There was little advantage at high boron levels and air heats were superior at high levels of boron plus zirconium. Vacuum heats also had fewer oxide and carbonitride inclusions although this was a function of the opportunity for separation of the inclusions from high oxygen plus nitrogen heats. The removal of phosphorous by vacuum melting was not found to be related to properties. Oxygen plus nitrogen appeared to increase ductility in creep-rupture tests suggesting that vacuum melting removes unidentified elements detrimental to ductility. Oxides and carbonitrides in themselves did not initiate microcracks. Carbonitrides in the grain boundaries of air heats did initiate microcracks. The role of microcracking from this source and as a function of oxygen and nitrogen content was not clear. Oxygen and nitrogen did intensify corner cracking during hot-rolling but were not responsible for poor surface which resulted from rolling heats melted in air.

Reducing Wear of Steel Rolling Against Ti6Al4V Operating in Vacuum

NASA Technical Reports Server (NTRS)

Krantz, Timothy L.

2014-01-01

This work was motivated by a qualification test of a mechanism for a space telescope. During the test undesired wear debris was formed. In this project alterative materials and coatings were tested with intent to reduce wear and debris when steel has a misaligned rolling contact against Ti6Al4V. Testing was done using a vacuum roller rig mimicking the mechanism's contact conditions. Ten configurations were tested. Most configurations resulted in significant debris. A sputtered 1-micrometer-thick nan-ocomposite molybdenum disulfide (MoS2) film provided the best wear protection. The best configuration made use of the MoS2 coating on both materials, and in preparing for sputtering the anodized Ti6Al4V working surface was smoothed using an ultrasonic process.

Retention of antioxidant capacity of vacuum microwave dried cranberry.

PubMed

Leusink, Gwen J; Kitts, David D; Yaghmaee, Parastoo; Durance, Tim

2010-04-01

In this study, cranberries were dried by vacuum-microwave drying (VMD), freeze-drying (FD), or hot air-drying (AD), to compare the effects of different drying processes on both physical changes as well as the retention of bioactive components in dried samples. Total porosity (%) and average pore radius of dehydrated cranberries were greater using VMD compared to FD and AD (P < 0.05). Crude methanol cranberry powdered extracts were fractionated by solid phase extraction (SPE) into organic acid-, total phenolics-, anthocyanin-, or proanthocyanidin-enriched extracts, respectively. The chemical composition of the 60% acidified methanol fractions contained cyanidin-3-galactoside, cyanidin-3-arabinoside, peonidin-3-galactoside, and peonidin-3-arabinoside, as assessed by HPLC. Antioxidant activities of cranberry fractions were measured using chemical ORAC and ABTS methods. The 60% acidified methanol fraction had a significantly higher (P < 0.05) antioxidant potential than the other chemical fractions, which was largely attributed to the relatively higher anthocyanin content. In general, vacuum-microwave drying and freeze-drying resulted in similar retention of anthocyanins and antioxidant activity, which were both relatively higher (P < 0.05) than that recovered from cranberries dried by hot air drying.

Vacuum Plasma Spraying Replaces Electrodeposition

NASA Technical Reports Server (NTRS)

Holmes, Richard R.; Power, Chris; Burns, David H.; Daniel, Ron; Mckechnie, Timothy N.

1992-01-01

Vacuum plasma spraying used to fabricate large parts with complicated contours and inner structures, without uninspectable welds. Reduces time, and expense of fabrication. Wall of combustion chamber built up inside of outer nickel-alloy jacket by plasma spraying. Particles of metal sprayed partially melted in plasma gun and thrown at supersonic speed toward deposition surface. Vacuum plasma-spray produces stronger bond between the grooves and covering layer completing channels and wall of combustion chamber. In tests, bond withstood pressure of 20 kpsi, three times allowable limit by old method.

Main Vacuum Technical Issues of Evacuated Tube Transportation

NASA Astrophysics Data System (ADS)

Zhang, Y. P.; Li, S. S.; Wang, M. X.

In the future, Evacuated Tube Transportation (ETT) would be built and faster than jets. ETT tube with diameter 2∼4m and length over 1000 km will be the largest scale vacuum equipment on earth. This paper listed some main vacuum technical issues to be solved in ETT as follow. How to build ultra-large-scale vacuum chamber like ETT tube with low cost and high reliability? How to pump gas out off the ETT tube in short time? How to release heat or reduce temperature in the vacuum tube? Hot to avoid vacuum electricity discharge? How to manufacture vehicles with airproof shells and equip the life support system? How to detect leakage and find leakage position efficiently and fast as possible? Some relative solutions and suggestions are put up.

Vacuum deposition and curing of liquid monomers apparatus

DOEpatents

Affinito, John D.

1996-01-01

The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of "standard" polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal or oxide may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface.

Indian Vacuum Society: The Indian Vacuum Society

NASA Astrophysics Data System (ADS)

Saha, T. K.

2008-03-01

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

33 CFR 157.130 - Crude oil washing with more than one grade of crude oil.

Code of Federal Regulations, 2010 CFR

2010-07-01

... RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Design... vessel having a COW system under §§ 157.10(e), 157.10a(a)(2), or 157.10c(b)(2) carries more than one grade of crude oil, the COW system must be capable of washing the cargo tanks with the grades of crude...

Carcass characteristics of feedlot lambs fed crude glycerin contaminated with high concentrations of crude fat.

PubMed

Lage, J F; Paulino, P V R; Pereira, L G R; Duarte, M S; Valadares Filho, S C; Oliveira, A S; Souza, N K P; Lima, J C M

2014-01-01

Thirty non-castrated male lambs with 20±2.3 kg average body weight (BW) were randomly assigned to five treatments consisted of different dietary concentrations of crude glycerin (CG; 0, 3, 6, 9 and 12% on DM basis) to evaluate the effects on performance, carcass and meat quality traits. A quadratic effect was observed for performance (P=0.04), final BW (P<0.01) and hot carcass weight (P<0.01). No effects of CG were observed (P>0.05) on carcass pH neither on shear-force, cooking loss and ether extract content in longissimus. The inclusion of CG tended to reduce the Zn content in meat (P=0.09). The data suggests that CG (36.2% of glycerol and 46.5% of crude fat) may be used in diets of finishing lambs with concentrations up to 3% without negative effects on performance and main carcass traits. Moreover, inclusion of CG seems to not affect quality and safety of meat for human consumption. Copyright © 2013 Elsevier Ltd. All rights reserved.

Vacuum deposition and curing of liquid monomers apparatus

DOEpatents

Affinito, J.D.

1996-08-20

The present invention is the formation of solid polymer layers under vacuum. More specifically, the present invention is the use of ``standard`` polymer layer-making equipment that is generally used in an atmospheric environment in a vacuum, and degassing the monomer material prior to injection into the vacuum. Additional layers of polymer or metal or oxide may be vacuum deposited onto solid polymer layers. Formation of polymer layers under a vacuum improves material and surface characteristics, and subsequent quality of bonding to additional layers. Further advantages include use of less to no photoinitiator for curing, faster curing, fewer impurities in the polymer electrolyte, as well as improvement in material properties including no trapped gas resulting in greater density, and reduced monomer wetting angle that facilitates spreading of the monomer and provides a smoother finished surface. 3 figs.

Milking performance evaluation and factors affecting milking claw vacuum levels with flow simulator.

PubMed

Enokidani, Masafumi; Kawai, Kazuhiro; Shinozuka, Yasunori; Watanabe, Aiko

2017-08-01

Milking performance of milking machines that matches the production capability of dairy cows is important in reducing the risk of mastitis, particularly in high-producing cows. This study used a simulated milking device to examine the milking performance of the milking system of 73 dairy farms and to analyze the factors affecting claw vacuum. Mean claw vacuum and range of fluctuation of claw vacuum (claw vacuum range) were measured at three different flow rates: 5.7, 7.6 and 8.7 kg/min. At the highest flow rate, only 16 farms (21.9%) met both standards of mean claw vacuum ≥35 kPa and claw vacuum range ≤ 7 kPa, showing that milking systems currently have poor milking performance. The factors affecting mean claw vacuum were claw type, milk-meter and vacuum shut-off device; the factor affecting claw vacuum range was claw type. Examination of the milking performance of the milking system using a simulated milking device allows an examination of the performance that can cope with high producing cows, indicating the possibility of reducing the risk of mastitis caused by inappropriate claw vacuum. © 2016 Japanese Society of Animal Science.

Vacuum Outgassing of High Density Polyethylene

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

Dinh, L N; Sze, J; Schildbach, M A

A combination of thermogravimetric analysis (TGA) and temperature programmed decomposition (TPD) was employed to identify the outgassing species, the total amount of outgassing, and the outgassing kinetics of high density polyethylene (HDPE) in a vacuum environment. The isoconversional kinetic analysis was then used to analyze the outgassing kinetics and to predict the long-term outgassing of HDPE in vacuum applications at ambient temperature. H{sub 2}O and C{sub n}H{sub x} with n as high as 9 and x centering around 2n are the major outgassing species from solid HDPE, but the quantities evolved can be significantly reduced by vacuum baking at 368more » K for a few hours prior to device assembly.« less

Use of Vacuum Degreasing for Precision Cleaning

NASA Technical Reports Server (NTRS)

Fox, Eric; Edwards, Kevin; Mitchell, Mark; Boothe, Richard

2017-01-01

Increasingly strict environmental regulations and the consequent phase out of many effective cleaning solvents has necessitated the development of novel cleaning chemistries and technologies. Among these is vacuum degreasing, a fully enclosed process that eliminates fugitive solvent emissions, thereby reducing cost, environmental, and health related exposure impacts. The effectiveness of vacuum degreasing using modified alcohol for common aerospace contaminants is reported and compared to current and legacy solvents.

California crude-pipeline plans detailed

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

Ronco, M.J.

1986-06-09

California and the U.S. West have recently become a center for crude-oil pipeline activity. That activity includes existing and proposed lines, offshore and onshore terminals, and some unusual permitting and construction requirements. Operation of existing pipelines is influenced by the varying gravities of crudes in the area. California has three distinct producing areas from which pipelines deliver crude to refineries or marines terminals: 1. The inland Los Angeles basin and coast from Orange County to Ventura County. 2. The San Joaquin Valley in central California which is between the coastal mountains and the Sierras. 3. That portion of the Outermore » Continental Shelf (OCS) located primarily in federal waters off Santa Barbara and San Luis Obispo counties on the central coast. The Los Angeles coastal and inland basin crude-oil pipeline system consists of gathering lines to move crude from the many wells throughout Ventura, Orange, and Los Angeles counties to operating refineries in the greater Los Angeles area. Major refineries include ARCO at Carson, Chevron at El Segundo, Mobil at Torrance, and Shell, Texaco, and Unical at Wilmington. The many different crude-oil pipelines serving these refineries from Ventura County and Orange County and from the many sites around Los Angeles County are too numerous to list.« less

Silicon crystal growth in vacuum

NASA Technical Reports Server (NTRS)

Khattak, C. P.; Schmid, F.

1982-01-01

The most developed process for silicon crystal growth is the Czochralski (CZ) method which was in production for over two decades. In an effort to reduce cost of single crystal silicon for photovoltaic applications, a directional solidification technique, Heat Exchanger Method (HEM), was adapted. Materials used in HEM and CZ furnaces are quite similar (heaters, crucibles, insulation, etc.). To eliminate the cost of high purity argon, it was intended to use vacuum operation in HEM. Two of the major problems encountered in vacuum processing of silicon are crucible decomposition and silicon carbide formation in the melt.

Improved Aerogel Vacuum Thermal Insulation

NASA Technical Reports Server (NTRS)

Ruemmele, Warren P.; Bue, Grant C.

2009-01-01

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

Isolation and characterization of two crude oil-degrading fungi strains from Rumaila oil field, Iraq.

PubMed

Al-Hawash, Adnan B; Alkooranee, Jawadayn T; Abbood, Hayder A; Zhang, Jialong; Sun, Jin; Zhang, Xiaoyu; Ma, Fuying

2018-03-01

Among four crude oil-degrading fungi strains that were isolated from a petroleum-polluted area in the Rumaila oil field, two fungi strains showed high activity in aliphatic hydrocarbon degradation. ITS sequencing and analysis of morphological and biochemical characteristics identified these strains as Penicillium sp. RMA1 and RMA2. Gravimetric and gas chromatography analysis of the crude oil remaining in the culture medium after 14 days of incubation at 30 °C showed that RMA1 and RMA2 degraded the crude oil by 57% and 55%, respectively. These strains reduced surface tension when cultured on crude oil (1% v/v) and exhibited a cell surface hydrophobicity of more than 70%. These results suggested that RMA1 and RMA2 performed effective crude oil-degrading activity and crude oil emulsification. In conclusion, these fungal strains can be used in bioremediation process and oil pollution reduction in aquatic ecosystems.

Plates for vacuum thermal fusion

DOEpatents

Davidson, James C.; Balch, Joseph W.

2002-01-01

A process for effectively bonding arbitrary size or shape substrates. The process incorporates vacuum pull down techniques to ensure uniform surface contact during the bonding process. The essence of the process for bonding substrates, such as glass, plastic, or alloys, etc., which have a moderate melting point with a gradual softening point curve, involves the application of an active vacuum source to evacuate interstices between the substrates while at the same time providing a positive force to hold the parts to be bonded in contact. This enables increasing the temperature of the bonding process to ensure that the softening point has been reached and small void areas are filled and come in contact with the opposing substrate. The process is most effective where at least one of the two plates or substrates contain channels or grooves that can be used to apply vacuum between the plates or substrates during the thermal bonding cycle. Also, it is beneficial to provide a vacuum groove or channel near the perimeter of the plates or substrates to ensure bonding of the perimeter of the plates or substrates and reduce the unbonded regions inside the interior region of the plates or substrates.

[Dual chamber safety vacuum--initial experiences with a new suction cup].

PubMed

Korell, M; King, S; Hepp, H

1994-06-01

The main problem with vacuum extraction methods, alongside the cephalhaematoma produced, is the premature separation of the suction cup under traction, since the resulting sudden change in pressure can lead to severe intra-cerebral damage to the child. To reduce the risk of vaginal operative delivery, a new double-chamber safety vacuum extractor has been developed by Hepp/King. The basic feature of this instrument is an additional chamber with a thin overlapping area, which surrounds the actual suction cup and serves as a safety vacuum. If the suction cup starts to slip, the external vacuum is released and sounds an alarm. In addition, the inner vacuum has been designed to be convex and to reduce the volume of scalp, which is sucked into the vacuum, thus reducing the size of the cephalhaematoma produced. First experiences in clinical use demonstrated the reliability of the early warning signal, if the direction of traction is false or the applied traction is too strong. The inner vacuum remains constant at 0.8 atu, so that with care, the extraction can continue without interruption. We have used the new instrument in 18 deliveries. In 15 cases, the indication was failure to progress into the second stage of labour; in one case history of retinal detachment and in two cases signs of foetal asphyxia. In all cases, the child was delivered following one or two contractions with traction, without losing the vacuum. The average weight of the newborn was 3566 g. As expected, the cephalohaematoma produced was very much smaller than usual. Further clinical trials are necessary before the value of this new instrument can be assessed.

Impacts of the Venezuelan Crude Oil Production Loss

EIA Publications

2003-01-01

This assessment of the Venezuelan petroleum loss examines two areas. The first part of the analysis focuses on the impact of the loss of Venezuelan crude production on crude oil supply for U.S. refiners who normally run a significant fraction of Venezuelan crude oil. The second part of the analysis looks at the impact of the Venezuelan production loss on crude markets in general, with particular emphasis on crude oil imports, refinery crude oil throughput levels, stock levels, and the changes in price differences between light and heavy crude oils.

Research on construction settlement of different soft foundation under vacuum preloading condition

NASA Astrophysics Data System (ADS)

Bin, LI; Changquan, YIN

2017-11-01

Vacuum preloading, rigid foundation, raft foundation and piled raft foundation are more commonly used in soft foundation treatment. PLAXIS is large finite element software of rock and soil, which can simulate the influence of different foundation forms. After the vacuum preloading treatment, the foundation settlement is reduced by 80%, the raft foundation settlement is reduced by 60%, the pile raft foundation settlement is reduced by 40%. It is suggested that the vacuum preloading is used to deal with the foundation of the building. If the time limit, the pile raft foundation is used as the foundation form of the foundation is better than others.

7 CFR 30.20 - Crude.

Code of Federal Regulations, 2011 CFR

2011-01-01

... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.20 Crude. A subdegree of maturity, crude leaves usually have the general appearance of being raw and...

7 CFR 30.20 - Crude.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.20 Crude. A subdegree of maturity, crude leaves usually have the general appearance of being raw and...

7 CFR 30.20 - Crude.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.20 Crude. A subdegree of maturity, crude leaves usually have the general appearance of being raw and...

7 CFR 30.20 - Crude.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.20 Crude. A subdegree of maturity, crude leaves usually have the general appearance of being raw and...

7 CFR 30.20 - Crude.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.20 Crude. A subdegree of maturity, crude leaves usually have the general appearance of being raw and...

Vacuum Pump System Optimization Saves Energy at a Dairy Farm

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

None

In 1998, S&S Dairy optimized the vacuum pumping system at their dairy farm in Modesto, California. In an effort to reduce energy costs, S&S Dairy evaluated their vacuum pumping system to determine if efficiency gains and energy savings were possible.

The effect of vacuum devices on penile hemodynamics

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

Katz, P.G.; Haden, H.T.; Mulligan, T.

1990-01-01

External vacuum devices are being used increasingly for the management of erectile dysfunction. There is limited information regarding the effect of vacuum devices on penile blood flow and potential for ischemic penile injury. The penile xenon washout rate was measured before and after application of 2 vacuum systems in 15 subjects. Compared to flaccid state measurements the xenon washout rate did not change significantly with the Synergist Erection System but it was significantly reduced with the Osbon ErecAid System. However, the degree and duration of decrease in penile blood flow that may result in ischemic changes are unknown.

Rubber-coated bellows improves vibration damping in vacuum lines

NASA Technical Reports Server (NTRS)

Hegland, D. E.; Smith, R. J.

1966-01-01

Compact-vibration damping systems, consisting of rubber-coated metal bellows with a sliding O-ring connector, are used in vacuum lines. The device presents a metallic surface to the vacuum system and combines flexibility with the necessary stiffness. It protects against physical damage, reduces fatigue failure, and provides easy mating of nonparallel lines.

Vacuum mechatronics

NASA Technical Reports Server (NTRS)

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

1989-01-01

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

Effect of surface polishing and vacuum firing on electron stimulated desorption from 316LN stainless steel

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

Malyshev, Oleg B., E-mail: oleg.malyshev@stfc.ac.uk; Hogan, Benjamin T.; Pendleton, Mark

2014-09-01

The reduction of thermal outgassing from stainless steel by surface polishing or vacuum firing is well-known in vacuum technology, and the consequent use of both techniques allows an even further reduction of outgassing. The aim of this study was to identify the effectiveness of surface polishing and vacuum firing for reducing electron-stimulated desorption (ESD) from 316LN stainless steel, which is a frequently used material for particle accelerator vacuum chambers and components. It was found that, unlike for thermal outgassing, surface polishing does not reduce the ESD yield and may even increase it, while vacuum firing of nonpolished sample reduces onlymore » the H{sub 2} ESD yield by a factor 2.« less

Thermodynamic performance of multi-stage gradational lead screw vacuum pump

NASA Astrophysics Data System (ADS)

Zhao, Fan; Zhang, Shiwei; Sun, Kun; Zhang, Zhijun

2018-02-01

As a kind of dry mechanical vacuum pump, the twin-screw vacuum pump has an outstanding pumping performance during operation, widely used in the semiconductor industry. Compared with the constant lead screw (CLS) vacuum pump, the gradational lead screw (GLS) vacuum pump is more popularly applied in recent years. Nevertheless, not many comparative studies on the thermodynamic performance of GLS vacuum pump can be found in the literature. Our study focuses on one type of GLS vacuum pump, the multi-stage gradational lead screw (MGLS) vacuum pump, gives a detailed description of its construction and illustrates it with the drawing. Based on the structural analysis, the thermodynamic procedure is divided into four distinctive processes, including sucking process, transferring (compressing) process, backlashing process and exhausting process. The internal mechanism of each process is qualitatively illustrated and the mathematical expressions of seven thermodynamic parameters are given under the ideal situation. The performance curves of MGLS vacuum pump are plotted by MATLAB software and compared with those of the CLS vacuum pump in the same case. The results can well explain why the MGLS vacuum pump has more favorable pumping performance than the CLS vacuum pump in saving energy, reducing noise and heat dissipation.

Natural vacuum electronics

NASA Technical Reports Server (NTRS)

Leggett, Nickolaus

1990-01-01

The ambient natural vacuum of space is proposed as a basis for electron valves. Each valve is an electron controlling structure similiar to a vacuum tube that is operated without a vacuum sustaining envelope. The natural vacuum electron valves discussed offer a viable substitute for solid state devices. The natural vacuum valve is highly resistant to ionizing radiation, system generated electromagnetic pulse, current transients, and direct exposure to space conditions.

VACUUM TRAP

DOEpatents

Gordon, H.S.

1959-09-15

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

Characterization of crude glycerol from biodiesel plants.

PubMed

Hu, Shengjun; Luo, Xiaolan; Wan, Caixia; Li, Yebo

2012-06-13

Characterization of crude glycerol is very important to its value-added conversion. In this study, the physical and chemical properties of five biodiesel-derived crude glycerol samples were determined. Three methods, including iodometric-periodic acid method, high performance liquid chromatography (HPLC), and gas chromatography (GC), were shown to be suitable for the determination of glycerol content in crude glycerol. The compositional analysis of crude glycerol was successfully achieved by crude glycerol fractionation and characterization of the obtained fractions (aqueous and organic) using titrimetric, HPLC, and GC analyses. The aqueous fraction consisted mainly of glycerol, methanol, and water, while the organic fraction contained fatty acid methyl esters (FAMEs), free fatty acids (FFAs), and glycerides. Despite the wide variations in the proportion of their components, all raw crude glycerol samples were shown to contain glycerol, soap, methanol, FAMEs, water, glycerides, FFAs, and ash.

Degumming of crude palm oil by membrane filtration.

PubMed

Ong, K K; Fakhru'l-Razi, A; Baharin, B S; Hassan, M A

1999-01-01

The application of membrane separation in palm oil refining process has potential for energy and cost savings. The conventional refining of crude palm oil results in loss of oil and a contaminated effluent. Degumming of crude palm oil by membrane technology is conducted in this study. The objective of this research is to study the feasibility of membrane filtration for the removal of phospholipids in the degumming of crude palm oil, including analyses of phosphorus content, carotene content free fatty acids (as palmitic acid), colour and volatile matter. A PCI membrane module was used which was equipped with polyethersulfone membranes having a molecular weight cut off of 9,000 (type ES209). In this study, phosphorus content was the most important parameter monitored. The membrane effectively removed phospholipids resulting in a permeate with a phosphorus content of less than 0.3 ppm The percentage removal of phosphorus was 96.4% and was considered as a good removal. Lovibond colour was reduced from 27R 50Y to 20R 30Y. The percentage removal of carotene was 15.8%. The removal of colour was considered good but the removal of carotene was considered insignificant by the membrane. Free fatty acids and volatile matter were not removed. Typical of membrane operations, the permeate flux decreased with time and must be improved in order to be adopted on an industrial scale. Membrane technology was found to have good potential in crude palm oil degumming. However, an appropriate method has to be developed to clean the membranes for reuse.

Rapid comprehensive characterization of crude oils by thermogravimetry coupled to fast modulated gas chromatography-single photon ionization time-of-flight mass spectrometry.

PubMed

Wohlfahrt, S; Fischer, M; Saraji-Bozorgzad, M; Matuschek, G; Streibel, T; Post, E; Denner, T; Zimmermann, R

2013-09-01

Comprehensive multi-dimensional hyphenation of a thermogravimetry device (i.e. a thermobalance) to gas chromatography and single photon ionization-time-of-flight mass spectrometry (TG-GC×SPI-MS) has been used to investigate two crude oil samples of different geographical origin. The source of the applied vacuum ultraviolet radiation is an electron beam pumped rare gas excimer lamp (EBEL). The soft photoionization favors the formation of molecular ions. Introduction of a fast, rapidly modulated gas chromatographic separation step in comparison with solely TG-SPI-MS enables strongly enhanced detection especially with such highly complex organic matrices as crude oil. In contrast with former TG-SPI-MS measurements, separation and identification of overlying substances is possible because of different GC retention times. The specific contribution of isobaric compounds to one mass signal is determined for alkanes, naphthalenes, alkylated benzenes, and other compounds.

Integrated structure vacuum tube

NASA Technical Reports Server (NTRS)

Dimeff, J.; Kerwin, W. J. (Inventor)

1976-01-01

High efficiency, multi-dimensional thin film vacuum tubes suitable for use in high temperature, high radiation environments are described. The tubes are fabricated by placing thin film electrode members in selected arrays on facing interior wall surfaces of an alumina substrate envelope. Cathode members are formed using thin films of triple carbonate. The photoresist used in photolithography aids in activation of the cathodes by carbonizing and reacting with the reduced carbonates when heated in vacuum during forming. The finely powdered triple carbonate is mixed with the photoresist used to delineate the cathode locations in the conventional solid state photolithographic manner. Anode and grid members are formed using thin films of refractory metal. Electron flow in the tubes is between grid elements from cathode to anode as in a conventional three-dimensional tube.

Embryotoxic effects of crude oil in mallard ducks and chicks

USGS Publications Warehouse

Hoffman, David J.

1978-01-01

Recent studies in this laboratory have revealed that surface applications of microliter amounts of some crude and fuel oils that coat less than 10% of the egg surface reduce hatching considerably in different avian species. Applications of paraffin compounds that coat equal areas of the egg surface do not reduce hatching suggesting that toxicity is due to causes other than asphyxia. In the present study, 1–10 μl of South Louisiana crude oil, an API reference oil, were applied to the surface of fertile mallard (Anas platyrhynchos) and chicken (Gallus gallus) eggs. Early embryolethality was greater in mallard embryos than in chick embryos, but later embryolethality that coincided with the time of rapid outgrowth of the chorioallantoic membrane was more prevalent in chick embryos. The overall incidence of embryolethality was similar in both species. Retardation of growth as reflected by embryonic body weight, crown-rump length, beak length, and general appearance was more pronounced in chick than mallard embryos. Teratogenic defects were more frequent in chick embryos, and incomplete or abnormal ossification of the skull was the most common. External application of equivalent amounts of a mixture of paraffin compounds present in crude oil had virtually no embryotoxic effects in either species, suggesting that other components including aromatic hydrocarbons and organometallics may cause the embryotoxicity.

19 CFR 19.22 - Withdrawal of metal refined in part from imported crude metal and in part from crude metal...

Code of Federal Regulations, 2011 CFR

2011-04-01

... 19 Customs Duties 1 2011-04-01 2011-04-01 false Withdrawal of metal refined in part from imported crude metal and in part from crude metal produced from imported materials. 19.22 Section 19.22 Customs... § 19.22 Withdrawal of metal refined in part from imported crude metal and in part from crude metal...

19 CFR 19.22 - Withdrawal of metal refined in part from imported crude metal and in part from crude metal...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Withdrawal of metal refined in part from imported crude metal and in part from crude metal produced from imported materials. 19.22 Section 19.22 Customs... § 19.22 Withdrawal of metal refined in part from imported crude metal and in part from crude metal...

Degassing procedure for ultrahigh vacuum

NASA Technical Reports Server (NTRS)

Moore, B. C.

1979-01-01

Calculations based on diffusion coefficients and degassing rates for stainless-steel vacuum chambers indicate that baking at lower temperatures for longer periods give lower ultimate pressures than rapid baking at high temperatures. Process could reduce pressures in chambers for particle accelerators, fusion reactors, material research, and other applications.

Impact of vacuum frying on quality of potato crisps and frying oil.

PubMed

Belkova, Beverly; Hradecky, Jaromir; Hurkova, Kamila; Forstova, Veronika; Vaclavik, Lukas; Hajslova, Jana

2018-02-15

This research was focused on a critical assessment of vacuum frying as a technology enabling minimization of acrylamide formation in potato crisps and reducing undesirable chemical changes that occur in frying oil at high temperatures. The potato slices were fried in rapeseed oil under vacuum at 125°C and atmospheric pressure at 165°C. The experiments were performed on two potato varieties, Saturna and Impala. Vacuum frying reduced the formation of acrylamide by 98% and also other Maillard reaction products, specifically alkylpyrazines. Concurrently a lower extent of oxidative changes was observed in the frying oil, while 3-MCPD esters decreased fairly quickly during conventional frying. Sensory characteristics of the vacuum and conventionally fried potato crisps were evaluated by a 23-member panel. The majority of panellists preferred the flavour of 'conventional crisps', while only a few of them appreciated potato-like fresh flavour of 'vacuum crisps' and classified this product as 'tasty'. Copyright © 2017. Published by Elsevier Ltd.

Adsorption of crude and engine oils from water using raw rice husk.

PubMed

Razavi, Zahra; Mirghaffari, Nourollah; Rezaei, Behzad

2014-01-01

The raw rice husk (RRH) was used as a low cost adsorbent to remove three oil compounds with different viscosities (crude oil, engine oil and spent engine oil) from an aqueous environment. Some of the sorbent specifications were characterized using a CHNSO analyzer, Fourier transform infrared, scanning electron microscope and inductively coupled plasma spectroscopy. With decreasing RRH particles size, the oil adsorption percentage was reduced for crude, spent and engine oils from 50 to 30%, 65 to 20% and 70 to 0.01%, respectively. This was probably due to damage of the microcavities. The removal percentage by sorbent at optimized conditions was 88, 80 and 55% for engine, spent and crude oils, respectively, corresponding to their descending viscosity. The adsorption of crude and spent oils on rice husk followed the Freundlich isotherm model, while the adsorption of engine oil was fitted by the Langmuir model. The maximum adsorption capacity (qmax), calculated from the Langmuir model for the adsorption of engine oil on RRH, was 1,250 mg/g.

Plasma corticosterone and thyroxine concentrations during chronic ingestion of crude oil in mallard ducks (Anas platyrhynchos)

USGS Publications Warehouse

Rattner, B.A.; Eastin, W.C.

1981-01-01

1. Blood samples were collected from mallard ducks after 6, 12, and 18 weeks of dietary exposure to mash containing 0.015%, 0.150%, and 1.500% crude oil.2. Plasma corticosterone concentrations in ducks fed mash containing 0.150% or 1.500% Alaskan Prudhoe Bay crude oil were uniformly depressed when compared to values in untreated control birds.3. Plasma thyroxine concentration was not altered in ducks chronically exposed to crude oil.4. The observed alteration in corticosterone concentration could reduce tolerance to temperature and dietary fluctuations in the environment.

7 CFR 29.2261 - Crude.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Crude. 29.2261 Section 29.2261 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing.... A similar condition may result from fire-kill, sunburn, or sunscald. Any leaf which is crude to the...

Method and apparatus for in-cell vacuuming of radiologically contaminated materials

DOEpatents

Spadaro, Peter R.; Smith, Jay E.; Speer, Elmer L.; Cecconi, Arnold L.

1987-01-01

A vacuum air flow operated cyclone separator arrangement for collecting, handling and packaging loose contaminated material in accordance with acceptable radiological and criticality control requirements. The vacuum air flow system includes a specially designed fail-safe prefilter installed upstream of the vacuum air flow power supply. The fail-safe prefilter provides in-cell vacuum system flow visualization and automatically reduces or shuts off the vacuum air flow in the event of an upstream prefilter failure. The system is effective for collecting and handling highly contaminated radiological waste in the form of dust, dirt, fuel element fines, metal chips and similar loose material in accordance with radiological and criticality control requirements for disposal by means of shipment and burial.

Synthetic Minor NSR Permit: Van Hook Crude Terminal, LLC - Van Hook Crude Terminal/Rail Loading Facility

EPA Pesticide Factsheets

This page contains the current effective synthetic minor NSR permit for the Van Hook Crude Terminal, LLC, Van Hook Crude Terminal/Rail Loading Facility, located on the Fort Berthold Indian Reservation in Mountrail County, ND.

Crude protein supplementation to reduce lupine consumption by pregnant cattle in the scablands of eastern Washington.

USDA-ARS?s Scientific Manuscript database

Lupinus leucophyllus (velvet lupine) is prevalent in eastern Washington, and when consumed by pregnant cows, can cause “crooked calf disease.” Rangelands in this region are dominated by poor quality annual grasses. The objective of this study was to determine if feeding supplemental crude protein...

7 CFR 29.3015 - Crude.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Crude. 29.3015 Section 29.3015 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... immaturity. A similar condition may result from sunburn or sunscald. Any leaf which is crude to the extent of...

Comprehensive Chemical Characterization of Hydrocarbons in NIST Standard Reference Material 2779 Gulf of Mexico Crude Oil.

PubMed

Worton, David R; Zhang, Haofei; Isaacman-VanWertz, Gabriel; Chan, Arthur W H; Wilson, Kevin R; Goldstein, Allen H

2015-11-17

Comprehensive chemical information is needed to understand the environmental fate and impact of hydrocarbons released during oil spills. However, chemical information remains incomplete because of the limitations of current analytical techniques and the inherent chemical complexity of crude oils. In this work, gas chromatography (GC)-amenable C9-C33 hydrocarbons were comprehensively characterized from the National Institute of Standards and Technology Standard Reference Material (NIST SRM) 2779 Gulf of Mexico crude oil by GC coupled to vacuum ultraviolet photoionization mass spectrometry (GC/VUV-MS), with a mass balance of 68 ± 22%. This technique overcomes one important limitation faced by traditional GC and even comprehensive 2D gas chromatography (GC×GC): the necessity for individual compounds to be chromatographically resolved from one another in order to be characterized. VUV photoionization minimizes fragmentation of the molecular ions, facilitating the characterization of the observed hydrocarbons as a function of molecular weight (carbon number, NC), structure (number of double bond equivalents, NDBE), and mass fraction (mg kg(-1)), which represent important metrics for understanding their fate and environmental impacts. Linear alkanes (8 ± 1%), branched alkanes (11 ± 2%), and cycloalkanes (37 ± 12%) dominated the mass with the largest contribution from cycloalkanes containing one or two rings and one or more alkyl side chains (27 ± 9%). Linearity and good agreement with previous work for a subset of >100 components and for the sum of compound classes provided confidence in our measurements and represents the first independent assessment of our analytical approach and calibration methodology. Another crude oil collected from the Marlin platform (35 km northeast of the Macondo well) was shown to be chemically identical within experimental errors to NIST SRM 2779, demonstrating that Marlin crude is an appropriate surrogate oil for researchers conducting

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

PubMed

Topcuoglu, Canan; Sezer, Sevilay; Kosem, Arzu; Ercan, Mujgan; Turhan, Turan

2017-12-01

Urine collection systems with aspiration system for vacuum tubes are becoming increasingly common for urinalysis, especially for microscopic examination of the urine. In this study, we aimed to examine whether vacuum aspiration of the urine sample has any adverse effect on sediment analysis by comparing results from vacuum and non-vacuum urine tubes. The study included totally 213 urine samples obtained from inpatients and outpatients in our hospital. Urine samples were collected to containers with aspiration system for vacuum tubes. Each sample was aliquoted to both vacuum and non-vacuum urine tubes. Urinary sediment analysis was performed using manual microscope. Results were evaluated using chi-square test. Comparison of the sediment analysis results from vacuum and non-vacuum urine tubes showed that results were highly concordant for erythrocyte, leukocyte and epithelial cells (gamma values 1, 0.997, and 0.994, respectively; p < .001). Results were also concordant for urinary casts, crystals and yeast (kappa values 0.815, 0.945 and 1, respectively; p < .001). The results show that in urinary sediment analysis, vacuum aspiration has no adverse effect on the cellular components except on casts.

Embryotoxicity of weathered crude oil from the Gulf of Mexico in mallard ducks (Anas platyrhynchos).

PubMed

Finch, Bryson E; Wooten, Kimberly J; Smith, Philip N

2011-08-01

Weathered crude oil in the Gulf of Mexico can result from oil spills such as the Deepwater Horizon incident that occurred on April 20, 2010 or from natural seeps. Adult waterbirds of the Gulf Coast region may become exposed to weathered crude oil while foraging, wading, or resting, and residues can then be transferred to nests, eggs, and hatchlings. Although the toxicity of many types of crude oil to avian embryos has been thoroughly studied, the effects of weathered crude oil on developing avian embryos are not well characterized. The objective of the present study was to examine embryotoxicity of weathered crude oil collected from the Gulf of Mexico in June 2010 using mallard ducks (Anas platyrhynchos) as a model species. Weathered crude oil was applied to fertilized mallard duck eggs by paintbrush in masses ranging from 0.1 to 99.9 mg on day 3 of incubation. Mortality occurred as early as day 7 and the conservatively derived median lethal application of weathered crude oil was 30.8 mg/egg (0.5 mg/g egg) or 30.7 µl/egg (0.5 µl/g egg). Body mass, liver and spleen mass, crown-rump and bill lengths, and frequency of deformities were not significantly different among hatchlings from oiled and control eggs. In comparison to published reports of fresh crude oil embryotoxicity, weathered crude oil was considerably less toxic. We conclude that avian toxicity varies according to the degree of crude oil weathering and the stage of embryonic development at the time of exposure. Results indicate bird eggs exposed to weathered crude oil from the Gulf of Mexico during summer 2010 may have had reduced hatching success. Copyright © 2011 SETAC.

Research on crude oil storage and transportation based on optimization algorithm

NASA Astrophysics Data System (ADS)

Yuan, Xuhua

2018-04-01

At present, the optimization theory and method have been widely used in the optimization scheduling and optimal operation scheme of complex production systems. Based on C++Builder 6 program development platform, the theoretical research results are implemented by computer. The simulation and intelligent decision system of crude oil storage and transportation inventory scheduling are designed. The system includes modules of project management, data management, graphics processing, simulation of oil depot operation scheme. It can realize the optimization of the scheduling scheme of crude oil storage and transportation system. A multi-point temperature measuring system for monitoring the temperature field of floating roof oil storage tank is developed. The results show that by optimizing operating parameters such as tank operating mode and temperature, the total transportation scheduling costs of the storage and transportation system can be reduced by 9.1%. Therefore, this method can realize safe and stable operation of crude oil storage and transportation system.

DOE/DOT Crude Oil Characterization Research Study, Task 2 Test Report on Evaluating Crude Oil Sampling and Analysis Methods

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

Lord, David; Allen, Ray; Rudeen, David

The Crude Oil Characterization Research Study is designed to evaluate whether crude oils currently transported in North America, including those produced from "tight" formations, exhibit physical or chemical properties that are distinct from conventional crudes, and how these properties associate with combustion hazards with may be realized during transportation and handling.

Development of a large low-cost double-chamber vacuum laminator

NASA Technical Reports Server (NTRS)

Burger, D. R.

1983-01-01

A double-chamber vacuum laminator was required to investigate the processing and control of the fabrication of large terrestrial photovoltaic modules, and economic problems arising therefrom. Major design considerations were low cost, process flexibility and the exploration of novel equipment approaches. Spherical end caps for industrial tanks were used for the vacuum chambers. A stepping programmer and adjustable timers were used for process flexibility. New processing options were obtained by use of vacuum sensors. The upper vacuum chamber was provided with a diaphragm support to reduce diaphragm stress. A counterweight was used for handling ease and safety. Heat was supplied by a large electrical strip heater. Thermal isolation and mechanical support were provided inexpensively by a bed of industrial marbles. Operational testing disclosed the need for a differential vacuum gauge and proportional valve. Reprogramming of the process control system was simple and quick.

49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... The following requirements apply to vehicles with vacuum brake assist units and vacuum brake systems. (a) Vacuum brake assist unit integrity. The vacuum brake assist unit shall demonstrate integrity as... maintained on the pedal. (1) Inspection procedure. Stop the engine and apply service brake several times to...

The proposal of recommendations for the operation of vacuum sewerage

NASA Astrophysics Data System (ADS)

Mazák, J.; Dvorský, T.; Václavík, V.; Zajac, R.; Hluštík, P.

2017-10-01

This article deals with a comparison of vacuum sewerage system and gravity based sewerage system. It also includes the results of the comparison of both of these systems from various cities, and there are measures suggested on the basis of the findings focused on increasing the efficiency and reducing the operational costs of the selected vacuum sewerage system.

Demonstrations with a Vacuum: Old Demonstrations for New Vacuum Pumps.

ERIC Educational Resources Information Center

Greenslade, Thomas B., Jr.

1989-01-01

Explains mechanisms of 19th-century vacuum pumps. Describes demonstrations using the pump including guinea and feather tube, aurora tube, electric egg, Gassiots cascade, air mill, bell in vacuum, density and buoyancy of air, fountain in vacuum, mercury shower, palm and bladder glasses, Bacchus demonstration, pneumatic man-lifter, and Magdeburg…

Assessment of crude oil biodegradation in arctic seashore sediments: effects of temperature, salinity, and crude oil concentration.

PubMed

Sharma, Priyamvada; Schiewer, Silke

2016-08-01

The expected increase in offshore oil exploration and production in the Arctic may lead to crude oil spills along arctic shorelines. To evaluate the potential effectiveness of bioremediation to treat such spills, oil spill bioremediation in arctic sediments was simulated in laboratory microcosms containing beach sediments from Barrow (Alaska), spiked with North Slope Crude, and incubated at varying temperatures and salinities. Biodegradation was measured via respiration rates (CO2 production); volatilization was quantified by gas chromatography/mass spectrophotometry (GC/MS) analysis of hydrocarbons sorbed to activated carbon, and hydrocarbons remaining in the sediment were quantified by GC/flame ionization detector (FID). Higher temperature leads to increased biodegradation by naturally occurring microorganisms, while the release of volatile organic compounds was similar at both temperatures. Increased salinity had a small positive impact on crude oil removal. At higher crude oil dosages, volatilization increased, however CO2 production did not. While only a small percentage of crude oil was completely biodegraded, a larger percentage was volatilized within 6-9 weeks.

Phytoremediation of crude oil contaminated soil using nut grass, Cyperus rotundus.

PubMed

Basumatary, Budhadev; Saikia, Rubul; Bordoloi, Sabitry

2012-09-01

The aim of this study was to evaluate the efficacy of Cyperus rotundus (nut grass), that could be effective in phytoremediation of crude oil contaminated soil. A net house experiment was conducted with different concentrations (2.05, 4.08, 6.1, 8.15 and 10.2%) of crude oil-contaminated soil for 180 days. Plant growth, biomass, total oil and grease (TOG) degradation and microbial numbers were analyzed at different intervals i.e. 60,120 and 180 days in different percentages of crude oil contaminated soil. In presence of crude oil, plant biomass and heights reduced up to 26 and 21.9% respectively. Concerning TOG content in soil, C. rotundus could decrease up to 50.01, 46.1, 42.6, 38.8 and 32.6% in treatment I, II, III, IV and V respectively in vegetated pots during 180 days. In case of unvegetated pots, the reductions of TOG were 4.4, 5.6, 6.6, 7.6 and 9.6% in treatment A, B, C, D and E respectively. However, there was significant degradation (P = 0.05) of TOG in vegetated pots in comparison to unvegetated pots thereby proving the efficacy of this plant species for use in phytoremediation.

Improved Vacuum Bazooka

NASA Astrophysics Data System (ADS)

Cockman, John

2003-04-01

This apparatus is a modification to the well-known "vacuum bazooka" (PIRA 2B30.70). My vacuum bazooka is easy to construct and demonstrate, requires no precise fittings, foil, or vacuum grease, and propels ping-pong balls at a tremendous velocity!

Chemical demulsification of tanker crude emulsions. Memorandum report

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

Little, R.C.

1980-02-13

The chemical demulsification of tanker crude emulsions was studied as a function of oil type (light vs. heavy crude), demulsifier concentrations, and temperature. Aerosol OT shows promise as a chemical demulsifier of tanker crude emulsions provided that ambient temperatures are not too cold and that an appropriate concentration range is used for specific oil. The evaporation rates and viscosities of the six crudes studied are also reported in the text.

A high-vacuum wound drainage system reduces pain and length of treatment for pediatric soft tissue abscesses.

PubMed

Yang, Chao; Wang, Shan; Li, Chang-Chun; Kong, Xiang-Ru; Zhao, Zhenzhen; Deng, Xiao-Bin; Peng, Liang; Zhang, Jun

2017-02-01

Open incision and drainage (I&D) and wound packing is accepted as the standard treatment for soft tissue abscesses. However, conventional I&D has a number of problems in practice which prompt us to improve the I&D methods that would minimize the pain associated with packing during dressing changes. In order to compare the pain associated with dressing changes in the conventional I&D group to the vacuum system group and the treatment time of both groups, we performed a randomized trial in pediatric patients between 0 and 18 years of age who are undergoing abscess drainage in the operating room from April 2011 to April 2015. Patients treated with open I&D (n = 648) were compared to those treated with placement of high-vacuum wound drainage system (n = 776) through the abscess cavities. Both groups received equivalent antibiotic treatment, and all patients were followed up in the outpatient clinics until the infection has been resolved. The mean FACES scale pain scores were significantly higher in the open I&D group than in the vacuum system group. The vacuum system group had a shorter length of stay and less need for community doctor or outpatient dressing changes than the open I&D group (p < 0.001). No recurrent abscesses were observed in the vacuum system group, and 10 patients in the open I&D group required another drainage at the exact same location. High-vacuum wound drainage system was an efficient and safe alternative to the traditional I&D for community-acquired soft tissue abscesses with few complications in short term. What is Known: • Open incision and drainage (I&D) followed by irrigation and wound packing is the standard treatment for soft tissue abscesses. • The painful daily packing may cause emotional trauma to the child and lead to an unwelcoming challenge to the caretakers and health care providers. What is New: • We modified the method of I&D by adding primary suturing of the wound and placement of a high-vacuum wound drainage system

Vacuum-integrated electrospray deposition for highly reliable polymer thin film.

PubMed

Park, Soohyung; Lee, Younjoo; Yi, Yeonjin

2012-10-01

Vacuum electrospray deposition (ESD) equipment was designed to prepare polymer thin films. The polymer solution can be injected directly into vacuum system through multi-stage pumping line, so that the solvent residues and ambient contaminants are highly reduced. To test the performance of ESD system, we fabricated organic photovoltaic cells (OPVCs) by injecting polymer solution directly onto the substrate inside a high vacuum chamber. The OPVC fabricated has the structure of Al∕P3HT:PCBM∕PEDOT:PSS∕ITO and was optimized by varying the speed of solution injection and concentration of the solution. The power conversion efficiency (PCE) of the optimized OPVC is 3.14% under AM 1.5G irradiation without any buffer layer at the cathode side. To test the advantages of the vacuum ESD, we exposed the device to atmosphere between the deposition steps of the active layer and cathode. This showed that the PCE of the vacuum processed device is 24% higher than that of the air exposed device and confirms the advantages of the vacuum prepared polymer film for high performance devices.

The Classical Vacuum.

ERIC Educational Resources Information Center

Boyer, Timothy H.

1985-01-01

The classical vacuum of physics is not empty, but contains a distinctive pattern of electromagnetic fields. Discovery of the vacuum, thermal spectrum, classical electron theory, zero-point spectrum, and effects of acceleration are discussed. Connection between thermal radiation and the classical vacuum reveals unexpected unity in the laws of…

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

NASA Astrophysics Data System (ADS)

Kohri, Kazunori; Matsui, Hiroki

2017-08-01

In this work, we investigated the electroweak vacuum instability during or after inflation. In the inflationary Universe, i.e., de Sitter space, the vacuum field fluctuations < δ phi 2 > enlarge in proportion to the Hubble scale H2. Therefore, the large inflationary vacuum fluctuations of the Higgs field < δ phi 2 > are potentially catastrophic to trigger the vacuum transition to the negative-energy Planck-scale vacuum state and cause an immediate collapse of the Universe. However, the vacuum field fluctuations < δ phi 2 >, i.e., the vacuum expectation values have an ultraviolet divergence, and therefore a renormalization is necessary to estimate the physical effects of the vacuum transition. Thus, in this paper, we revisit the electroweak vacuum instability from the perspective of quantum field theory (QFT) in curved space-time, and discuss the dynamical behavior of the homogeneous Higgs field phi determined by the effective potential V eff( phi ) in curved space-time and the renormalized vacuum fluctuations < δ phi 2 >ren via adiabatic regularization and point-splitting regularization. We simply suppose that the Higgs field only couples the gravity via the non-minimal Higgs-gravity coupling ξ(μ). In this scenario, the electroweak vacuum stability is inevitably threatened by the dynamical behavior of the homogeneous Higgs field phi, or the formations of AdS domains or bubbles unless the Hubble scale is small enough H< ΛI .

Effects of Louisiana crude oil on the sheepshead minnow ...

EPA Pesticide Factsheets

Determining the long-term effects of crude oil exposure is critical for ascertaining population-level ecological risks of spill events. A 19-week complete life-cycle experiment was conducted with the estuarine sheepshead minnow (Cyprinodon variegatus) exposed to reference (uncontaminated) sediment spiked with laboratory weathered South Louisiana crude (SLC) oil at five concentrations as well as one unspiked sediment control and one seawater (no sediment) control. Newly hatched larvae were exposed to the oiled sediments at measured concentrations of < 1 (sediment control), 50, 103, 193, 347, and 711 mg total polyaromatic hydrocarbons (tPAH)/kg dry sediment. Juveniles were exposed through the reproductively active adult phase at measured concentrations of <1 (sediment control), 52, 109, 199, 358, and 751 mg tPAH/kg sediment. Throughout the exposure, fish were assessed for growth, survival, and reproduction. Resulting F1 embryos were then collected, incubated, and hatched in clean water to determine if parental full life-cycle exposure to oiled sediment produced trans-generational effects. Larvae experienced significantly reduced standard length (5–13% reduction) and wet weight (13–35% reduction) at concentrations at and above 50 and 103 mg tPAH/kg sediment, respectively. At 92 and 132 days post hatch (dph), standard length was reduced (7–13% reduction) at 199 and 109 mg tPAH/kg dry sediment, respectively, and wet weight for both time periods was reduced

Expanding space-time and variable vacuum energy

NASA Astrophysics Data System (ADS)

Parmeggiani, Claudio

2017-08-01

The paper describes a cosmological model which contemplates the presence of a vacuum energy varying, very slightly (now), with time. The constant part of the vacuum energy generated, some 6 Gyr ago, a deceleration/acceleration transition of the metric expansion; so now, in an aged Universe, the expansion is inexorably accelerating. The vacuum energy varying part is instead assumed to be eventually responsible of an acceleration/deceleration transition, which occurred about 14 Gyr ago; this transition has a dynamic origin: it is a consequence of the general relativistic Einstein-Friedmann equations. Moreover, the vacuum energy (constant and variable) is here related to the zero-point energy of some quantum fields (scalar, vector, or spinor); these fields are necessarily described in a general relativistic way: their structure depends on the space-time metric, typically non-flat. More precisely, the commutators of the (quantum field) creation/annihilation operators are here assumed to depend on the local value of the space-time metric tensor (and eventually of its curvature); furthermore, these commutators rapidly decrease for high momentum values and they reduce to the standard ones for a flat metric. In this way, the theory is ”gravitationally” regularized; in particular, the zero-point (vacuum) energy density has a well defined value and, for a non static metric, depends on the (cosmic) time. Note that this varying vacuum energy can be negative (Fermi fields) and that a change of its sign typically leads to a minimum for the metric expansion factor (a ”bounce”).

Germanium detector vacuum encapsulation

NASA Technical Reports Server (NTRS)

Madden, N. W.; Malone, D. F.; Pehl, R. H.; Cork, C. P.; Luke, P. N.; Landis, D. A.; Pollard, M. J.

1991-01-01

This paper describes an encapsulation technology that should significantly improve the viability of germanium gamma-ray detectors for a number of important applications. A specialized vacuum chamber has been constructed in which the detector and the encapsulating module are processed in high vacuum. Very high vacuum conductance is achieved within the valveless encapsulating module. The detector module is then sealed without breaking the chamber vacuum. The details of the vacuum chamber, valveless module, processing, and sealing method are presented.

Rheological behavior on treated Malaysian crude oil

NASA Astrophysics Data System (ADS)

Chandran, Krittika; Sinnathambi, Chandra Mohan

2016-11-01

Crude oil is always produced with water. This association causes many problems during oil production, arising from the formation of emulsion. Emulsion is an undesirable substance that increases operational and capital cost in the pipeline and processing equipment. To overcome this issue, demulsifiers are formulated to break the emulsion, where they are able to separate the water-oil emulsions to their respective phases. The emulsifier's main function is to reduce the interfacial tension properties of the emulsion. For this research, both the EOR and natural water-in-oil emulsions were treated with low a concentration demulsifier. The main objective of this paper is to determine the dynamic viscosity and rheological properties of the treated EOR and natural emulsion. The dynamic viscosity was obtained using the Brook-field Digital Viscometer. The components that influence the emulsion's rheological properties are the temperature, shear rate and shear stress. The results obtained demonstrate that the viscosity of the treated crude decreases and portrays the Non-Newtonian shear thinning "pseudo-plastic" behavior. Besides that, to determine the interfacial film of the treated crude, the spinning drop tensiometer was used. With the addition of demulsifier, the thinning rate of the oil film accelerates whereby there is a linear decrease in the interfacial tension with an increase in time. Therefore, from the results, it can be observed that the rheology study plays a significant role in the demulsification test. Furthermore, both the rheology approaches showed that time, temperature, shear rate and shear stress have a great impact on the viscosity behavior as well as the IFT.

Crude oil degradation by bacterial consortia under four different redox and temperature conditions.

PubMed

Xiong, Shunzi; Li, Xia; Chen, Jianfa; Zhao, Liping; Zhang, Hui; Zhang, Xiaojun

2015-02-01

There is emerging interest in the anaerobic degradation of crude oil. However, there is limited knowledge about the geochemical effects and microbiological activities for it. A mixture of anaerobic sludge and the production water from an oil well was used as an inoculum to construct four consortia, which were incubated under sulfate-reducing or methanogenic conditions at either mesophilic or thermophilic temperatures. Significant degradation of saturated and aromatic hydrocarbons and the changing quantities of some marker compounds, such as pristane, phytane, hopane and norhopane, and their relative quantities, suggested the activity of microorganisms in the consortia. Notably, the redox conditions and temperature strongly affected the diversity and structure of the enriched microbial communities and the oil degradation. Although some specific biomarker showed larger change under methanogenic condition, the degradation efficiencies for total aromatic and saturated hydrocarbon were higher under sulfate-reducing condition. After the 540-day incubation, bacteria of unknown classifications were dominant in the thermophilic methanogenic consortia, whereas Clostridium dominated the mesophilic methanogenic consortia. With the exception of the dominant phylotypes that were shared with the methanogenic consortia, the sulfate-reducing consortia were predominantly composed of Thermotogae, Deltaproteobacteria, Spirochaeta, and Synergistetes phyla. In conclusion, results in this study demonstrated that the different groups of degraders were responsible for degradation in the four constructed crude oil degrading consortia and consequently led to the existence of different amount of marker compounds under these distinct conditions. There might be distinct metabolic mechanism for degrading crude oil under sulfate-reducing and methanogenic conditions.

Enrichment and isolation of crude oil degrading bacteria from some mussels collected from the Persian Gulf.

PubMed

Bayat, Zeynab; Hassanshahian, Mehdi; Hesni, Majid Askari

2015-12-15

To date, little is known about existing relationships between mussels and bacteria in hydrocarbon-contaminated marine environments. The aim of this study is to find crude oil degrading bacteria in some mussels at the Persian Gulf. Twenty eight crude oil degrading bacteria were isolated from three mussels species collected from oil contaminated area at Persian Gulf. According to high growth and degradation of crude oil four strains were selected between 28 isolated strains for more study. Determination the nucleotide sequence of the gene encoding for 16S rRNA show that these isolated strains belong to: Shewanella algae isolate BHA1, Micrococcus luteus isolate BHA7, Pseudoalteromonas sp. isolate BHA8 and Shewanella haliotis isolate BHA35. The residual crude oil in culture medium was analysis by Gas Chromatography (GC). The results confirmed that these strains can degrade: 47.24%, 66.08%, 27.13% and 69.17% of crude oil respectively. These strains had high emulsification activity and biosurfactant production. Also, the effects of some factors on crude oil degradation by isolated strains were studied. The results show that the optimum concentration of crude oil was 2.5% and the best degradation take place at 12% of salinity. This research is the first reports on characterization of crude oil degrading bacteria from mussels at Persian Gulf and by using of these bacteria in the field the effect of oil pollution can be reduce on this marine environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Simultaneous valorization and biocatalytic upgrading of heavy vacuum gas oil by the biosurfactant-producing Pseudomonas aeruginosa AK6U.

PubMed

Ismail, Wael Ahmed; Mohamed, Magdy El-Said; Awadh, Maysoon N; Obuekwe, Christian; El Nayal, Ashraf M

2017-11-01

Heavy vacuum gas oil (HVGO) is a complex and viscous hydrocarbon stream that is produced as the bottom side product from the vacuum distillation units in petroleum refineries. HVGO is conventionally treated with thermochemical process, which is costly and environmentally polluting. Here, we investigate two petroleum biotechnology applications, namely valorization and bioupgrading, as green approaches for valorization and upgrading of HVGO. The Pseudomonas aeruginosa AK6U strain grew on 20% v/v of HVGO as a sole carbon and sulfur source. It produced rhamnolipid biosurfactants in a growth-associated mode with a maximum crude biosurfactants yield of 10.1 g l -1 , which reduced the surface tension of the cell-free culture supernatant to 30.6 mN m -1 within 1 week of incubation. The rarely occurring dirhamnolipid Rha-Rha-C 12 -C 12 dominated the congeners' profile of the biosurfactants produced from HVGO. Heavy vacuum gas oil was recovered from the cultures and abiotic controls and the maltene fraction was extracted for further analysis. Fractional distillation (SimDist) of the biotreated maltene fraction showed a relative decrease in the high-boiling heavy fuel fraction (BP 426-565 °C) concomitant with increase in the lighter distillate diesel fraction (BP 315-426 °C). Analysis of the maltene fraction revealed compositional changes. The number-average (Mn) and weight-average (Mw) molecular weights, as well as the absolute number of hydrocarbons and sulfur heterocycles were higher in the biotreated maltene fraction of HVGO. These findings suggest that HVGO can be potentially exploited as a carbon-rich substrate for production of the high-value biosurfactants by P. aeruginosa AK6U and to concomitantly improve/upgrade its chemical composition. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

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

NASA Astrophysics Data System (ADS)

Niwa, Yoshimitsu; Kaneko, Eiji

Vacuum circuit breakers (VCB) have been widely used for power distribution systems. Vacuum Interrupters, which are the current interruption unit, have been increased its interruption capability with the development of vacuum arc control technology by magnetic field. There are three major type electrodes: disk shaped electrodes, radial magnetic field electrodes, axial magnetic field (AMF) electrodes. In the disk shaped electrode, the vacuum arc between the electrodes is not controlled. In the AMF electrode, the vacuum arc is diffused and stabilized by an axial magnetic field, which is parallel to the arc current. In the last type of electrodes, the vacuum arc column is rotated by magnetic force generated by the current flowing in the electrodes. The interruption current and the voltage of one break VCB is increased to 100 kA, 144 kV respectively. This paper describes basic configurations and functions of VCB, vacuum arc control technology in vacuum interrupters, recent researches and applications of VCB.

Venturi vacuum systems for hypobaric chamber operations.

PubMed

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.

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

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

Kohri, Kazunori; Matsui, Hiroki, E-mail: kohri@post.kek.jp, E-mail: matshiro@post.kek.jp

In this work, we investigated the electroweak vacuum instability during or after inflation. In the inflationary Universe, i.e., de Sitter space, the vacuum field fluctuations < δ φ {sup 2} > enlarge in proportion to the Hubble scale H {sup 2}. Therefore, the large inflationary vacuum fluctuations of the Higgs field < δ φ {sup 2} > are potentially catastrophic to trigger the vacuum transition to the negative-energy Planck-scale vacuum state and cause an immediate collapse of the Universe. However, the vacuum field fluctuations < δ φ {sup 2} >, i.e., the vacuum expectation values have an ultraviolet divergence, andmore » therefore a renormalization is necessary to estimate the physical effects of the vacuum transition. Thus, in this paper, we revisit the electroweak vacuum instability from the perspective of quantum field theory (QFT) in curved space-time, and discuss the dynamical behavior of the homogeneous Higgs field φ determined by the effective potential V {sub eff}( φ ) in curved space-time and the renormalized vacuum fluctuations < δ φ {sup 2} >{sub ren} via adiabatic regularization and point-splitting regularization. We simply suppose that the Higgs field only couples the gravity via the non-minimal Higgs-gravity coupling ξ(μ). In this scenario, the electroweak vacuum stability is inevitably threatened by the dynamical behavior of the homogeneous Higgs field φ, or the formations of AdS domains or bubbles unless the Hubble scale is small enough H < Λ {sub I} .« less

Reduction of benzene and naphthalene mass transfer from crude oils by aging-induced interfacial films.

PubMed

Ghoshal, Subhasis; Pasion, Catherine; Alshafie, Mohammed

2004-04-01

Semi-rigid films or skins form at the interface of crude oil and water as a result of the accumulation of asphaltene and resin fractions when the water-immiscible crude oil is contacted with water for a period of time or "aged". The time varying patterns of area-independent mass transfer coefficients of two compounds, benzene and naphthalene, for dissolution from crude oil and gasoline were determined. Aqueous concentrations of the compounds were measured in the eluent from flow-through reactors, where a nondispersed oil phase and constant oil-water interfacial area were maintained. For Brent Blend crude oil and for gasoline amended with asphaltenes and resins, a rapid decrease in both benzene and naphthalene mass transfer coefficients over the first few days of aging was observed. The mass transfer coefficients of the two target solutes were reduced by up to 80% over 35 d although the equilibrium partition coefficients were unchanged. Aging of gasoline, which has negligible amounts of asphaltene and resin, did not result in a change in the solute mass transfer coefficients. The study demonstrates that formation of crude oil-water interfacial films comprised of asphaltenes and resins contribute to time-dependent decreases in rates of release of environmentally relevant solutes from crude oils and may contribute to the persistence of such solutes at crude oil-contaminated sites. It is estimated that the interfacial film has an extremely low film mass transfer coefficient in the range of 10(-6) cm/min.

Superconducting Vacuum-Gap Crossovers for High Performance Microwave Applications

NASA Technical Reports Server (NTRS)

Denis, Kevin L.; Brown, Ari D.; Chang, Meng-Ping; Hu, Ron; U-Yen, Kongpop; Wollack, Edward J.

2016-01-01

The design and fabrication of low-loss wide-bandwidth superconducting vacuum-gap crossovers for high performance millimeter wave applications are described. In order to reduce ohmic and parasitic losses at millimeter wavelengths a vacuum gap is preferred relative to dielectric spacer. Here, vacuum-gap crossovers were realized by using a sacrificial polymer layer followed by niobium sputter deposition optimized for coating coverage over an underlying niobium signal layer. Both coplanar waveguide and microstrip crossover topologies have been explored in detail. The resulting fabrication process is compatible with a bulk micro-machining process for realizing waveguide coupled detectors, which includes sacrificial wax bonding, and wafer backside deep reactive ion etching for creation of leg isolated silicon membrane structures. Release of the vacuum gap structures along with the wax bonded wafer after DRIE is implemented in the same process step used to complete the detector fabrication. ?

Alaskan refiner raced against winter to relocate vacuum unit

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

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

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

Ethanol production from food waste at high solids content with vacuum recovery technology.

PubMed

Huang, Haibo; Qureshi, Nasib; Chen, Ming-Hsu; Liu, Wei; Singh, Vijay

2015-03-18

Ethanol production from food wastes does not only solve environmental issues but also provides renewable biofuels. This study investigated the feasibility of producing ethanol from food wastes at high solids content (35%, w/w). A vacuum recovery system was developed and applied to remove ethanol from fermentation broth to reduce yeast ethanol inhibition. A high concentration of ethanol (144 g/L) was produced by the conventional fermentation of food waste without a vacuum recovery system. When the vacuum recovery is applied to the fermentation process, the ethanol concentration in the fermentation broth was controlled below 100 g/L, thus reducing yeast ethanol inhibition. At the end of the conventional fermentation, the residual glucose in the fermentation broth was 5.7 g/L, indicating incomplete utilization of glucose, while the vacuum fermentation allowed for complete utilization of glucose. The ethanol yield for the vacuum fermentation was found to be 358 g/kg of food waste (dry basis), higher than that for the conventional fermentation at 327 g/kg of food waste (dry basis).

Thermal/vacuum vs. thermal atmospheric testing of space flight electronic assemblies

NASA Technical Reports Server (NTRS)

Gibbel, Mark

1990-01-01

For space flight hardware, the thermal vacuum environmental test is the best test of a system's flight worthiness. Substituting an atmospheric pressure thermal test for a thermal/vacuum test can effectively reduce piece part temperatures by 20 C or more, even for low power density designs. Similar reductions in test effectiveness can also result from improper assembly level T/V test boundary conditions. The net result of these changes may reduce the effective test temperatures to the point where there is zero or negative margin over the flight thermal environment.

Multiwall carbon nanotubes increase the microbial community in crude oil contaminated fresh water sediments.

PubMed

Abbasian, Firouz; Lockington, Robin; Palanisami, Thavamani; Megharaj, Mallavarapu; Naidu, Ravi

2016-01-01

Since crude oil contamination is one of the biggest environmental concerns, its removal from contaminated sites is of interest for both researchers and industries. In situ bioremediation is a promising technique for decreasing or even eliminating crude oil and hydrocarbon contamination. However, since these compounds are potentially toxic for many microorganisms, high loads of contamination can inhibit the microbial community and therefore reduce the removal rate. Therefore, any strategy with the ability to increase the microbial population in such circumstances can be of promise in improving the remediation process. In this study, multiwall carbon nanotubes were employed to support microbial growth in sediments contaminated with crude oil. Following spiking of fresh water sediments with different concentrations of crude oil alone and in a mixture with carbon nanotubes for 30days, the microbial profiles in these sediments were obtained using FLX-pyrosequencing. Next, the ratios of each member of the microbial population in these sediments were compared with those values in the untreated control sediment. This study showed that combination of crude oil and carbon nanotubes can increase the diversity of the total microbial population. Furthermore, these treatments could increase the ratios of several microorganisms that are known to be effective in the degradation of hydrocarbons. Copyright © 2015 Elsevier B.V. All rights reserved.

Vacuum energy density kicked by the electroweak crossover

NASA Astrophysics Data System (ADS)

Klinkhamer, F. R.; Volovik, G. E.

2009-10-01

Using q-theory, we show that the electroweak crossover can generate a remnant vacuum energy density Λ˜Eew8/EPlanck4, with effective electroweak energy scale Eew˜103GeV and reduced Planck-energy scale EPlanck˜1018GeV. The obtained expression for the effective cosmological constant Λ may be a crucial input for the suggested solution by Arkani-Hamed et al. of the triple cosmic coincidence puzzle (why the orders of magnitude of the energy densities of vacuum, matter, and radiation are approximately the same in the present Universe).

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

NASA Technical Reports Server (NTRS)

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

1971-01-01

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

Neutron scattering studies of crude oil viscosity reduction with electric field

NASA Astrophysics Data System (ADS)

Du, Enpeng

data that contains information on the properties of a sample. We can analyze the data acquisition from the detectors and get the information on size, shape, etc. This is why we choose SANS as our research tool. The world's top energy problems are security concerns, climate concerns and environmental concerns. So far, oil (37%) is still the No.1 fuel in world energy consumption (Oil 37%, Coal 25%, Bio-fuels 0.2%, Gas 23%, Nuclear 6%, Biomass 4%, Hydro 3%, Solar heat 0.5%, Wind 0.3%, Geothermal 0.2% and Solar photovoltaic 0.04%). Even more and more alternative energy: bio-fuels, nuclear and solar energy will be used in the future, but nuclear energy has a major safety issue after the Japanese Fukushima I nuclear accidents, and other energies contribute only a small percent. Thus, it is very important to improve the efficiency and reduce the population of petroleum products. There is probably one thing that we can all agree on: the world's energy reserves are not unlimited. Even though it is limited, only 30% of the oil reserves is conventional oil, so in order to produce, transport, and refine of heavy crude oil without wasting huge amounts of energy, we need to reduce the viscosity without using high temperature stream heating or diluent; As more and more off-shore oil is exploited at that we need reduce the viscosity without increasing temperature. The whole petroleum consumed in U.S. in 2009 was 18.7 million barrels per day and 35% of all the energy we consumed. Diesel is one of the very important fossil fuel which is about 20% of petroleum consumed. Most of the world's oils are non-conventional, 15 % of heavy oil, 25 % of extra heavy oil, 30 % of the oil sands and bitumen, and the conventional oil reserves is only 30%. The oil sand is closely related to the heavy crude oil, the main difference being that oil sands generally do not flow at all. For efficient energy production and conservation, how to lower the liquated fuel and crude oil viscosity is a very important

Effect of incubation time of sago (metroxylon sago) waste by local microorganism ″ginta″ on ph, crude protein, and crude fiber content

NASA Astrophysics Data System (ADS)

Ginting, Nurzainah; Pase, E.

2018-03-01

This study aims to examine the effect of incubation times of sago waste by local microorganism (MOL) “Ginta” to the crude protein and crude fiber content in relation to finding a cheap and good quality ruminants feed alternative. Incubation times were 0 hours to 144 hours. The data obtained were analyzed using Completely Randomize Design consisting of seven treatments and three replications. The result showed that the duration of incubation of sago waste by local microorganism (MOL) “Ginta” caused pH reduction, improved crude protein and crude fiber content. pH reduction was from 7.03 at 0 hour to 4.05 at 144 hours incubation. The highest increased in crude protein was H6U3 (5.58%) : 144 hours incubation and the lowest was H0U2 (3.22%) : 0 hour incubation while the highest crude fiber was H0U1 (19.99%) : 0 hour incubation and the lowest was H6U3 (18.23%) : 144 hours incubation. It can be concluded that incubation of sago waste triggered lower pH, higher crude protein and lower crude fiber than uninoculated. A recommendation could be given on using MOL ‘Ginta” in order to produce a cheap and good quality ruminans feed alternative.

10 CFR 212.78 - Tertiary incentive crude oil.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 3 2014-01-01 2014-01-01 false Tertiary incentive crude oil. 212.78 Section 212.78 Energy DEPARTMENT OF ENERGY OIL MANDATORY PETROLEUM PRICE REGULATIONS Producers of Crude Oil § 212.78 Tertiary incentive crude oil. Annual prepaid expenses report. By January 31 of each year after 1980, the project...

10 CFR 212.78 - Tertiary incentive crude oil.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 3 2013-01-01 2013-01-01 false Tertiary incentive crude oil. 212.78 Section 212.78 Energy DEPARTMENT OF ENERGY OIL MANDATORY PETROLEUM PRICE REGULATIONS Producers of Crude Oil § 212.78 Tertiary incentive crude oil. Annual prepaid expenses report. By January 31 of each year after 1980, the project...

10 CFR 212.78 - Tertiary incentive crude oil.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 3 2012-01-01 2012-01-01 false Tertiary incentive crude oil. 212.78 Section 212.78 Energy DEPARTMENT OF ENERGY OIL MANDATORY PETROLEUM PRICE REGULATIONS Producers of Crude Oil § 212.78 Tertiary incentive crude oil. Annual prepaid expenses report. By January 31 of each year after 1980, the project...

Crude oil degradation as an explanation of the depth rule

USGS Publications Warehouse

Price, L.C.

1980-01-01

Previous studies of crude oil degradation by water washing and bacterial attack have documented the operation of these processes in many different petroleum basins of the world. Crude oil degradation substantially alters the chemical and physical makeup of a crude oil, changing a light paraffinic low-S "mature" crude to a heavy naphthenic or asphalt base, "immature appearing" high-S crude. Rough calculations carried out in the present study using experimentally determined solubility data of petroleum in water give insight into the possible magnitude of water washing and suggest that the process may be able to remove large amounts of petroleum in small divisions of geologic time. Plots of crude oil gravity vs. depth fail to show the expected correlation of increasing API gravity (decreasing specific gravity) with depth below 2.44 km (8000 ft.). Previous studies which have been carried out to document in-reservoir maturation have used crude oil gravity data shallower than 2.44 km (8000 ft.). The changes in crude oil composition as a function of depth which have been attributed to in-reservoir maturation over these shallower depths, are better explained by crude oil degradation. This study concludes that changes in crude oil composition that result from in-reservoir maturation are not evident from existing crude oil gravity data over the depth and temperature range previously supposed, and that the significant changes in crude oil gravity which are present over the shallow depth range are due to crude oil degradation. Thus the existence of significant quantities of petroleum should not necessarily be ruled out below an arbitrarily determined depth or temperature limit when the primary evidence for this is the change in crude oil gravity at shallow depths. ?? 1980.

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

PubMed

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

2016-11-01

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

Inhibition of hepatitis B virus gene expression & replication by crude destruxins from Metarhizium anisopliae var. dcjhyium

PubMed Central

Dong, Cong; Yu, Jiuru; Zhu, Ying; Dong, Changjin

2013-01-01

Background & objectives: Destruxin A, destruxin B and destruxin E isolated from entomopathogenic fungus Metarhizium anisopliae showed a strong suppressive effect on the replication of hepatitis B virus (HBV) in human hepatoma cells. In this study, the anti-HBV effects of the crude destruxins extracted from M. anisopliae var. dcjhyium were detected both in vitro and in vivo. Methods: HepG2.2.15 cells were cultured to observe the inhibitory effects of the crude destruxins on the gene expression and replication of HBV by radioimmunoassay detection and real-time quantitative PCR. In vivo, duck HBV (DHBV)-infected ducks were treated with the crude destruxins at 2.0, 4.0, 6.0 μg/kg once a day for 15 days, DHBV DNA was examined by real-time quantitative PCR. Results: The crude destruxins suppressed the replication of HBV-DNA and the production of HBsAg and HBeAg with IC50 of about 1.2 and 1.4 μg/ml. Transcript of viral mRNA was significantly suppressed by the crude destruxins in HepG2.2.15 cells. In vivo, the duck serum DHBV-DNA levels were markedly reduced in the group of the crude destruxins. Interpretation & conclusions: The crude destruxins inhibited the gene expression and replication of HBV both in vitro and in vivo, and their anti-HBV effect was stronger than that with destruxin B. Our results indicate that the crude destruxins from M.anisopliae var. dcjhyium may be potential antivirus agents. Further studies need to be done to confirm these findings. PMID:24521644

Development of a Modified Vacuum Cleaner for Lunar Surface Systems

NASA Technical Reports Server (NTRS)

Toon, Katherine P.; Lee, Steve A.; Edgerly, Rachel D.

2009-01-01

The National Aeronautics and Space Administration (NASA) mission to expand space exploration will return humans to the Moon with the goal of maintaining a long-term presence. One challenge that NASA will face returning to the Moon is managing the lunar regolith found on the Moon's surface, which will collect on extravehicular activity (EVA) suits and other equipment. Based on the Apollo experience, the issues astronauts encountered with lunar regolith included eye/lung irritation, and various hardware failures (seals, screw threads, electrical connectors and fabric contamination), which were all related to inadequate lunar regolith mitigation. A vacuum cleaner capable of detaching, transferring, and efficiently capturing lunar regolith has been proposed as a method to mitigate the lunar regolith problem in the habitable environment on lunar surface. In order to develop this vacuum, a modified "off-the-shelf" vacuum cleaner has been used to determine detachment efficiency, vacuum requirements, and optimal cleaning techniques to ensure efficient dust removal in habitable lunar surfaces, EVA spacesuits, and air exchange volume. During the initial development of the Lunar Surface System vacuum cleaner, systematic testing was performed with varying flow rates on multiple surfaces (fabrics and metallics), atmospheric (14.7 psia) and reduced pressures (10.2 and 8.3 psia), different vacuum tool attachments, and several vacuum cleaning techniques to determine the performance requirements for the vacuum cleaner. The data recorded during testing was evaluated by calculating percent removal, relative to the retained simulant on the tested surface. In addition, Scanning Electron Microscopy (SEM) imaging was used to determine particle size distribution retained on the surface. The scope of this paper is to explain the initial phase of vacuum cleaner development, including historical Apollo mission data, current state-of-the-art vacuum cleaner technology, and vacuum cleaner

Development of a Modified Vacuum Cleaner for Lunar Surface Systems

NASA Technical Reports Server (NTRS)

Toon, Katherine P.; Lee, Steve A.; Edgerly, Rachel D.

2010-01-01

The National Aeronautics and Space Administration (NASA) mission to expand space exploration will return humans to the Moon with the goal of maintaining a long-term presence. One challenge that NASA will face returning to the Moon is managing the lunar regolith found on the Moon's surface, which will collect on extravehicular activity (EVA) suits and other equipment. Based on the Apollo experience, the issues astronauts encountered with lunar regolith included eye/lung irritation, and various hardware failures (seals, screw threads, electrical connectors and fabric contamination), which were all related to inadequate lunar regolith mitigation. A vacuum cleaner capable of detaching, transferring, and efficiently capturing lunar regolith has been proposed as a method to mitigate the lunar regolith problem in the habitable environment on lunar surface. In order to develop this vacuum, a modified "off-the-shelf' vacuum cleaner will be used to determine detachment efficiency, vacuum requirements, and optimal cleaning techniques to ensure efficient dust removal in habitable lunar surfaces, EVA spacesuits, and air exchange volume. During the initial development of the Lunar Surface System vacuum cleaner, systematic testing was performed with varying flow rates on multiple surfaces (fabrics and metallics), atmospheric (14.7 psia) and reduced pressures (10.2 and 8.3 psia), different vacuum tool attachments, and several vacuum cleaning techniques in order to determine the performance requirements for the vacuum cleaner. The data recorded during testing was evaluated by calculating particulate removal, relative to the retained simulant on the tested surface. In addition, optical microscopy was used to determine particle size distribution retained on the surface. The scope of this paper is to explain the initial phase of vacuum cleaner development, including historical Apollo mission data, current state-of-the-art vacuum cleaner technology, and vacuum cleaner testing that has

Thermal Considerations for Reducing the Cooldown and Warmup Duration of the James Webb Space Telescope OTIS Cryo-Vacuum Test

NASA Technical Reports Server (NTRS)

Yang, Kan; Glazer, Stuart; Ousley, Wes; Burt, William

2017-01-01

The James Webb Space Telescope (JWST), set to launch in 2018, is NASAs next-generation flagship telescope. The Optical Telescope Element (OTE) and Integrated Science Instrument Module (ISIM) contain all of the optical surfaces and instruments to capture and analyze the telescopes infrared targets. The integrated OTE and ISIM are denoted as OTIS, and will be tested as a single unit in a critical thermal-vacuum test in mid-2017 at NASA Johnson Space Centers Chamber A facility. The payload will be evaluated for workmanship and functionality in a 20K simulated flight environment during this thermal-vacuum test. However, the sheer thermal mass of the OTIS payload as well as the restrictive gradient, rate, and contamination-related constraints placed on test components precludes rapid cooldown or warmup to its steady-state cryo-balance condition. Hardware safety considerations precludes injection of helium gas for free molecular heat transfer. Initial thermal analysis predicted that transient radiative cooldown from ambient temperatures, while meeting all limits and constraints, would take 33.3 days; warmup similarly would take 28.4 days. This paper discusses methods used to reduce transition times from the original predictions through modulation of boundary temperatures and environmental conditions. By optimizing helium shroud transition rates and heater usage, as well as rigorously re-examining previously imposed constraints, savings of up to three days on cooldown and up to a week on warmup can be achieved. The efficiencies gained through these methods allow the JWST thermal test team to create faster cooldown and warmup profiles, thus reducing the overall test duration and cost, while keeping all of the required test operations.

Effects of Removing Restrictions on U.S. Crude Oil Exports

EIA Publications

2015-01-01

This report examines the implications of removing current restrictions on U.S. crude oil exports for the price of domestic and global marker crude oil streams, gasoline prices, domestic crude oil production, domestic refining activity, and trade in crude oil and petroleum products.

The vacuum system reform and test of the super-critical 600mw unit

NASA Astrophysics Data System (ADS)

Yan, Tao; Wan, Zhonghai; Lu, Jin; Chen, Wen; Cai, Wen

2017-11-01

The deficiencies of the designed vacuum system of the super-critical unit is pointed out in this paper, and then it is reformed by the steam ejector. The experimental results show that the vacuum of the condenser can be improved, the coal consumption can be reduced and the plant electricity consumption can be lowered dramatically at a small cost of the steam energy consumption. Meanwhile, the water-ring vacuum pumps cavitation problems can be solved.

Exposure to crude oil micro-droplets causes reduced food uptake in copepods associated with alteration in their metabolic profiles.

PubMed

Hansen, Bjørn Henrik; Altin, Dag; Nordtug, Trond; Øverjordet, Ida Beathe; Olsen, Anders J; Krause, Dan; Størdal, Ingvild; Størseth, Trond R

2017-03-01

Acute oil spills and produced water discharges may cause exposure of filter-feeding pelagic organisms to micron-sized dispersed oil droplets. The dissolved oil components are expected to be the main driver for oil dispersion toxicity; however, very few studies have investigated the specific contribution of oil droplets to toxicity. In the present work, the contribution of oil micro-droplet toxicity in dispersions was isolated by comparing exposures to oil dispersions (water soluble fraction with droplets) to concurrent exposure to filtered dispersions (water-soluble fractions without droplets). Physical (coloration) and behavioral (feeding activity) as well as molecular (metabolite profiling) responses to oil exposures in the copepod Calanus finmarchicus were studied. At high dispersion concentrations (4.1-5.6mg oil/L), copepods displayed carapace discoloration and reduced swimming activity. Reduced feeding activity, measured as algae uptake, gut filling and fecal pellet production, was evident also for lower concentrations (0.08mg oil/L). Alterations in metabolic profiles were also observed following exposure to oil dispersions. The pattern of responses were similar between two comparable experiments with different oil types, suggesting responses to be non-oil type specific. Furthermore, oil micro-droplets appear to contribute to some of the observed effects triggering a starvation-type response, manifested as a reduction in metabolite (homarine, acetylcholine, creatine and lactate) concentrations in copepods. Our work clearly displays a relationship between crude oil micro-droplet exposure and reduced uptake of algae in copepods. Copyright © 2017 Elsevier B.V. All rights reserved.

Comprehensive Chemical Characterization of Hydrocarbons in NIST Standard Reference Material 2779 Gulf of Mexico Crude Oil

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

Worton, David R.; Zhang, Haofei; Isaacman-VanWertz, Gabriel

Comprehensive chemical information is needed to understand the environmental fate and impact of hydrocarbons released during oil spills. However, chemical information remains incomplete because of the limitations of current analytical techniques and the inherent chemical complexity of crude oils. In this study, gas chromatography (GC)-amenable C 9-C 33 hydrocarbons were comprehensively characterized from the National Institute of Standards and Technology Standard Reference Material (NIST SRM) 2779 Gulf of Mexico crude oil by GC coupled to vacuum ultraviolet photoionization mass spectrometry (GC/VUV-MS), with a mass balance of 68 ± 22%. This technique overcomes one important limitation faced by traditional GC andmore » even comprehensive 2D gas chromatography (GC×GC): the necessity for individual compounds to be chromatographically resolved from one another in order to be characterized. VUV photoionization minimizes fragmentation of the molecular ions, facilitating the characterization of the observed hydrocarbons as a function of molecular weight (carbon number, N C), structure (number of double bond equivalents, N DBE), and mass fraction (mg kg -1), which represent important metrics for understanding their fate and environmental impacts. Linear alkanes (8 ± 1%), bran ched alkanes (11 ± 2%), and cycloalkanes (37 ± 12%) dominated the mass with the largest contribution from cycloalkanes containing one or two rings and one or more alkyl side chains (27 ± 9%). Linearity and good agreement with previous work for a subset of >100 components and for the sum of compound classes provided confidence in our measurements and represents the first independent assessment of our analytical approach and calibration methodology. Another crude oil collected from the Marlin platform (35 km northeast of the Macondo well) was shown to be chemically identical within experimental errors to NIST SRM 2779, demonstrating that Marlin crude is an appropriate surrogate oil for

Comprehensive Chemical Characterization of Hydrocarbons in NIST Standard Reference Material 2779 Gulf of Mexico Crude Oil

DOE PAGES

Worton, David R.; Zhang, Haofei; Isaacman-VanWertz, Gabriel; ...

2015-10-13

Comprehensive chemical information is needed to understand the environmental fate and impact of hydrocarbons released during oil spills. However, chemical information remains incomplete because of the limitations of current analytical techniques and the inherent chemical complexity of crude oils. In this study, gas chromatography (GC)-amenable C 9-C 33 hydrocarbons were comprehensively characterized from the National Institute of Standards and Technology Standard Reference Material (NIST SRM) 2779 Gulf of Mexico crude oil by GC coupled to vacuum ultraviolet photoionization mass spectrometry (GC/VUV-MS), with a mass balance of 68 ± 22%. This technique overcomes one important limitation faced by traditional GC andmore » even comprehensive 2D gas chromatography (GC×GC): the necessity for individual compounds to be chromatographically resolved from one another in order to be characterized. VUV photoionization minimizes fragmentation of the molecular ions, facilitating the characterization of the observed hydrocarbons as a function of molecular weight (carbon number, N C), structure (number of double bond equivalents, N DBE), and mass fraction (mg kg -1), which represent important metrics for understanding their fate and environmental impacts. Linear alkanes (8 ± 1%), bran ched alkanes (11 ± 2%), and cycloalkanes (37 ± 12%) dominated the mass with the largest contribution from cycloalkanes containing one or two rings and one or more alkyl side chains (27 ± 9%). Linearity and good agreement with previous work for a subset of >100 components and for the sum of compound classes provided confidence in our measurements and represents the first independent assessment of our analytical approach and calibration methodology. Another crude oil collected from the Marlin platform (35 km northeast of the Macondo well) was shown to be chemically identical within experimental errors to NIST SRM 2779, demonstrating that Marlin crude is an appropriate surrogate oil for

Radiation hard vacuum switch

DOEpatents

Boettcher, Gordon E.

1990-01-01

A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.

Radiation hard vacuum switch

DOEpatents

Boettcher, Gordon E.

1990-03-06

A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.

Hypolipidemic effects of crude green tea polysaccharide on rats, and structural features of tea polysaccharides isolated from the crude polysaccharide.

PubMed

Nakamura, Michiko; Miura, Sayaka; Takagaki, Akiko; Nanjo, Fumio

2017-05-01

Crude tea polysaccharide (crude TPS) was prepared from instant green tea by ethanol precipitation followed by ultrafiltration membrane treatment and its effects on blood lipid, liver lipid, and fecal lipid levels were examined with Sprague-Dawley rats fed a high-fat diet. Although crude TPS showed no effects on the serum lipid levels, it suppressed the liver lipid accumulation and increased the fecal excretion of dietary fat. Then, the structural features of crude TPS were investigated. After separation of crude TPS by DEAE-cellulose and gel-filtration column chromatography, two kinds of neutral tea polysaccharides (NTPS-LP and NTPS-HH) and an acidic polysaccharide (ATPS-MH) were obtained. According to monosaccharide composition, methylation, and NMR analyses, NTPS-LP, NPTS-HH, and ATPS-MH were presumed to be starch, arabinogalactan with β-1,3-linked galactosyl backbone blanched at position 6 and with 1,5-linked arabinofuranosyl residues, and α-1,4-linked galacturonic acid backbone with arabinogalactan region, respectively.

Impact of Expanded North Slope of Alaska Crude Oil Production on Crude Oil Flows in the Contiguous United States

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

DeRosa, Sean E.; Flanagan, Tatiana Paz

The National Transportation Fuels Model was used to simulate a hypothetical increase in North Slope of Alaska crude oil production. The results show that the magnitude of production utilized depends in part on the ability of crude oil and refined products infrastructure in the contiguous United States to absorb and adjust to the additional supply. Decisions about expanding North Slope production can use the National Transportation Fuels Model take into account the effects on crude oil flows in the contiguous United States.

Year in Review: Crude Oil Prices 2014

EIA Publications

2015-01-01

This report gives an overview of the primary drivers of crude oil price movements in 2014, in particular the substantial price decline that took place during the second half of the year. Factors such as increased global supply of crude oil, lower crude oil supply disruptions, lower economic growth expectations, and currency exchange rate movements are explored in the report. In addition, links are provided to several other published EIA articles with further in-depth discussion of topics related to the oil price decline.

Vacuum Baking To Remove Volatile Materials

NASA Technical Reports Server (NTRS)

Muscari, J. A.

1985-01-01

Outgassing reduced in some but not all nonmetallic materials. Eleven polymeric materials tested by determining outgassing species as temperature of conditioned and unconditioned materials raised to 300 degrees C. Conditioning process consisted of vacuum bake for 24 hours at 80 degrees C in addition to usual cure. Baking did not change residual gas percentage of water molecules.

Vacuum system design and tritium inventory for the TFTR charge exchange diagnostic

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

Medley, S.S.

The charge exchange diagnostic for the TFTR is comprised of two analyzer systems which contain a total of twenty independent mass/energy analyzers and one diagnostic neutral beam tentatively rated at 80 keV, 15 A. The associated vacuum systems were analyzed using the Vacuum System Transient Simulator (VSTS) computer program which models the transient transport of multi-gas species through complex networks of ducts, valves, traps, vacuum pumps, and other related vacuum system components. In addition to providing improved design performance at reduced cost, the analysis yields estimates for the exchange of tritium from the torus to the diagnostic components and ofmore » the diagnostic working gases to the torus.« less

Vacuum fluctuations in an ancestor vacuum: A possible dark energy candidate

NASA Astrophysics Data System (ADS)

Aoki, Hajime; Iso, Satoshi; Lee, Da-Shin; Sekino, Yasuhiro; Yeh, Chen-Pin

2018-02-01

We consider an open universe created by bubble nucleation, and study possible effects of our "ancestor vacuum," a de Sitter space in which bubble nucleation occurred, on the present universe. We compute vacuum expectation values of the energy-momentum tensor for a minimally coupled scalar field, carefully taking into account the effect of the ancestor vacuum by the Euclidean prescription. We pay particular attention to the so-called supercurvature mode, a non-normalizable mode on a spatial slice of the open universe, which has been known to exist for sufficiently light fields. This mode decays in time most slowly, and may leave residual effects of the ancestor vacuum, potentially observable in the present universe. We point out that the vacuum energy of the quantum field can be regarded as dark energy if mass of the field is of order the present Hubble parameter or smaller. We obtain preliminary results for the dark energy equation of state w (z ) as a function of the redshift.

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

NASA Astrophysics Data System (ADS)

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

2018-06-01

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

Analysis of crude oil markets with improved multiscale weighted permutation entropy

NASA Astrophysics Data System (ADS)

Niu, Hongli; Wang, Jun; Liu, Cheng

2018-03-01

Entropy measures are recently extensively used to study the complexity property in nonlinear systems. Weighted permutation entropy (WPE) can overcome the ignorance of the amplitude information of time series compared with PE and shows a distinctive ability to extract complexity information from data having abrupt changes in magnitude. Improved (or sometimes called composite) multi-scale (MS) method possesses the advantage of reducing errors and improving the accuracy when applied to evaluate multiscale entropy values of not enough long time series. In this paper, we combine the merits of WPE and improved MS to propose the improved multiscale weighted permutation entropy (IMWPE) method for complexity investigation of a time series. Then it is validated effective through artificial data: white noise and 1 / f noise, and real market data of Brent and Daqing crude oil. Meanwhile, the complexity properties of crude oil markets are explored respectively of return series, volatility series with multiple exponents and EEMD-produced intrinsic mode functions (IMFs) which represent different frequency components of return series. Moreover, the instantaneous amplitude and frequency of Brent and Daqing crude oil are analyzed by the Hilbert transform utilized to each IMF.

Measurement of the Rheology of Crude Oil in Equilibrium with CO2 at Reservoir Conditions.

PubMed

Hu, Ruien; Crawshaw, John

2017-06-06

A rheometer system to measure the rheology of crude oil in equilibrium with carbon dioxide (CO2) at high temperatures and pressures is described. The system comprises a high-pressure rheometer which is connected to a circulation loop. The rheometer has a rotational flow-through measurement cell with two alternative geometries: coaxial cylinder and double gap. The circulation loop contains a mixer, to bring the crude oil sample into equilibrium with CO2, and a gear pump that transports the mixture from the mixer to the rheometer and recycles it back to the mixer. The CO2 and crude oil are brought to equilibrium by stirring and circulation and the rheology of the saturated mixture is measured by the rheometer. The system is used to measure the rheological properties of Zuata crude oil (and its toluene dilution) in equilibrium with CO2 at elevated pressures up to 220 bar and a temperature of 50 °C. The results show that CO2 addition changes the oil rheology significantly, initially reducing the viscosity as the CO2 pressure is increased and then increasing the viscosity above a threshold pressure. The non-Newtonian response of the crude is also seen to change with the addition of CO2.

Analysis of inland crude oil spill threats, vulnerabilities, and emergency response in the midwest United States.

PubMed

Brody, Thomas M; Di Bianca, Paisly; Krysa, Jan

2012-10-01

Although coastal oil spills tend to be highly publicized, crude oil spills in the United States affect inland areas relatively often. Spills to inland areas often affect sensitive environments and can have greater impacts to health and welfare than spills to coastal areas. For these reasons, the authors investigated inland crude oil spill threats, vulnerabilities, and emergency response in the midwestern U.S. states of Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin. These states work with the Region 5 Offices of the U.S. Environmental Protection Agency. Region 5's geospatial data in the Inland Sensitivity Atlas were turned into metrics indicating inland crude oil spill threats and vulnerabilities among the Region's sub-watersheds. These threats and vulnerabilities were weighted using data from the National Response Center and the Department of Energy's Environmental Restoration Priority System. The locations of the Region's emergency responders were geocoded in GIS. The GIS calculated the emergency response times to the Region's sub-watersheds. The resulting scatter plots are connected to the sub-watersheds in the map so stakeholders can (1) see the outlying sub-watersheds of concern and (2) better understand how reducing threats and better response time can reduce the risk of inland crude oil spills. Published 2012. This article is a U.S. Government work and is in the public domain in the U.S.A.

Interactions between Zooplankton and Crude Oil: Toxic Effects and Bioaccumulation of Polycyclic Aromatic Hydrocarbons

PubMed Central

Almeda, Rodrigo; Wambaugh, Zoe; Wang, Zucheng; Hyatt, Cammie; Liu, Zhanfei; Buskey, Edward J.

2013-01-01

We conducted ship-, shore- and laboratory-based crude oil exposure experiments to investigate (1) the effects of crude oil (Louisiana light sweet oil) on survival and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in mesozooplankton communities, (2) the lethal effects of dispersant (Corexit 9500A) and dispersant-treated oil on mesozooplankton, (3) the influence of UVB radiation/sunlight exposure on the toxicity of dispersed crude oil to mesozooplankton, and (4) the role of marine protozoans on the sublethal effects of crude oil and in the bioaccumulation of PAHs in the copepod Acartia tonsa. Mortality of mesozooplankton increased with increasing oil concentration following a sigmoid model with a median lethal concentration of 32.4 µl L−1 in 16 h. At the ratio of dispersant to oil commonly used in the treatment of oil spills (i.e. 1∶20), dispersant (0.25 µl L−1) and dispersant- treated oil were 2.3 and 3.4 times more toxic, respectively, than crude oil alone (5 µl L−1) to mesozooplankton. UVB radiation increased the lethal effects of dispersed crude oil in mesozooplankton communities by 35%. We observed selective bioaccumulation of five PAHs, fluoranthene, phenanthrene, pyrene, chrysene and benzo[b]fluoranthene in both mesozooplankton communities and in the copepod A. tonsa. The presence of the protozoan Oxyrrhis marina reduced sublethal effects of oil on A. tonsa and was related to lower accumulations of PAHs in tissues and fecal pellets, suggesting that protozoa may be important in mitigating the harmful effects of crude oil exposure in copepods and the transfer of PAHs to higher trophic levels. Overall, our results indicate that the negative impact of oil spills on mesozooplankton may be increased by the use of chemical dispersant and UV radiation, but attenuated by crude oil-microbial food webs interactions, and that both mesozooplankton and protozoans may play an important role in fate of PAHs in marine environments. PMID:23840628

Vacuum Pyrolysis and Related ISRU Techniques

NASA Technical Reports Server (NTRS)

Cardiff, Eric H.; Pomeroy, Brian R.; Banks, Ian S.; Benz, Alexis

2007-01-01

A number of ISRU-related techniques have been developed at NASA Goddard Space Flight Center. The focus of the team has been on development of the vacuum pyrolysis technique for the production of oxygen from the lunar regolith. However, a number of related techniques have also been developed, including solar concentration, solar heating of regolith, resistive heating of regolith, sintering, regolith boiling, process modeling, parts manufacturing, and instrumentation development. An initial prototype system was developed to vaporize regolith simulants using a approx. l square meter Fresnel lens. This system was successfully used to vaporize quantities of approx. lg, and both mass spectroscopy of the gasses produced and Scanning Electron Microscopy (SEM) of the slag were done to show that oxygen was produced. Subsequent tests have demonstrated the use of a larger system With a 3.8m diameter reflective mirror to vaporize the regolith. These results and modeling of the vacuum pyrolysis reaction have indicated that the vaporization of the oxides in the regolith will occur at lower temperature for stronger vacuums. The chemical modeling was validated by testing of a resistive heating system that vaporized quantities of approx. 10g of MLS-1A. This system was also used to demonstrate the sintering of regolith simulants at reduced temperatures in high vacuum. This reduction in the required temperature prompted the development of a small-scale resistive heating system for application as a scientific instrument as well as a proof-of principle experiment for oxygen production.

Vacuum Virtues

ERIC Educational Resources Information Center

Rathey, Allen

2007-01-01

Upright vacuums, like cars, vary in quality, features and performance. Like automobiles, some uprights are reliable, others may be problematic, and some become a problem as a result of neglect or improper use. So, how do education institutions make an informed choice and, having done so, ensure that an upright vacuum goes the distance? In this…

Crude oil treatment leads to shift of bacterial communities in soils from the deep active layer and upper permafrost along the China-Russia Crude Oil Pipeline route.

PubMed

Yang, Sizhong; Wen, Xi; Zhao, Liang; Shi, Yulan; Jin, Huijun

2014-01-01

The buried China-Russia Crude Oil Pipeline (CRCOP) across the permafrost-associated cold ecosystem in northeastern China carries a risk of contamination to the deep active layers and upper permafrost in case of accidental rupture of the embedded pipeline or migration of oil spills. As many soil microbes are capable of degrading petroleum, knowledge about the intrinsic degraders and the microbial dynamics in the deep subsurface could extend our understanding of the application of in-situ bioremediation. In this study, an experiment was conducted to investigate the bacterial communities in response to simulated contamination to deep soil samples by using 454 pyrosequencing amplicons. The result showed that bacterial diversity was reduced after 8-weeks contamination. A shift in bacterial community composition was apparent in crude oil-amended soils with Proteobacteria (esp. α-subdivision) being the dominant phylum, together with Actinobacteria and Firmicutes. The contamination led to enrichment of indigenous bacterial taxa like Novosphingobium, Sphingobium, Caulobacter, Phenylobacterium, Alicylobacillus and Arthrobacter, which are generally capable of degrading polycyclic aromatic hydrocarbons (PAHs). The community shift highlighted the resilience of PAH degraders and their potential for in-situ degradation of crude oil under favorable conditions in the deep soils.

Crude Oil Treatment Leads to Shift of Bacterial Communities in Soils from the Deep Active Layer and Upper Permafrost along the China-Russia Crude Oil Pipeline Route

PubMed Central

Yang, Sizhong; Wen, Xi; Zhao, Liang; Shi, Yulan; Jin, Huijun

2014-01-01

The buried China-Russia Crude Oil Pipeline (CRCOP) across the permafrost-associated cold ecosystem in northeastern China carries a risk of contamination to the deep active layers and upper permafrost in case of accidental rupture of the embedded pipeline or migration of oil spills. As many soil microbes are capable of degrading petroleum, knowledge about the intrinsic degraders and the microbial dynamics in the deep subsurface could extend our understanding of the application of in-situ bioremediation. In this study, an experiment was conducted to investigate the bacterial communities in response to simulated contamination to deep soil samples by using 454 pyrosequencing amplicons. The result showed that bacterial diversity was reduced after 8-weeks contamination. A shift in bacterial community composition was apparent in crude oil-amended soils with Proteobacteria (esp. α-subdivision) being the dominant phylum, together with Actinobacteria and Firmicutes. The contamination led to enrichment of indigenous bacterial taxa like Novosphingobium, Sphingobium, Caulobacter, Phenylobacterium, Alicylobacillus and Arthrobacter, which are generally capable of degrading polycyclic aromatic hydrocarbons (PAHs). The community shift highlighted the resilience of PAH degraders and their potential for in-situ degradation of crude oil under favorable conditions in the deep soils. PMID:24794099

Partial-Vacuum-Gasketed Electrochemical Corrosion Cell

NASA Technical Reports Server (NTRS)

Bonifas, Andrew P.; Calle, Luz M.; Hintze, Paul E.

2006-01-01

An electrochemical cell for making corrosion measurements has been designed to prevent or reduce crevice corrosion, which is a common source of error in prior such cells. The present cell (see figure) includes an electrolyte reservoir with O-ring-edged opening at the bottom. In preparation for a test, the reservoir, while empty, is pressed down against a horizontal specimen surface to form an O-ring seal. A purge of air or other suitable gas is begun in the reservoir, and the pressure in the reservoir is regulated to maintain a partial vacuum. While maintaining the purge and partial vacuum, and without opening the interior of the reservoir to the atmosphere, the electrolyte is pumped into the reservoir. The reservoir is then slowly lifted a short distance off the specimen. The level of the partial vacuum is chosen such that the differential pressure is just sufficient to keep the electrolyte from flowing out of the reservoir through the small O-ring/specimen gap. Electrochemical measurements are then made. Because there is no gasket (and, hence, no crevice between the specimen and the gasket), crevice corrosion is unlikely to occur.

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

NASA Technical Reports Server (NTRS)

Grisnik, Stanley P.; Parkes, James E.

1994-01-01

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

Nearly Seamless Vacuum-Insulated Boxes

NASA Technical Reports Server (NTRS)

Stepanian, Christopher J.; Ou, Danny; Hu, Xiangjun

2010-01-01

A design concept, and a fabrication process that would implement the design concept, have been proposed for nearly seamless vacuum-insulated boxes that could be the main structural components of a variety of controlled-temperature containers, including common household refrigerators and insulating containers for shipping foods. In a typical case, a vacuum-insulated box would be shaped like a rectangular parallelepiped conventional refrigerator box having five fully closed sides and a hinged door on the sixth side. Although it is possible to construct the five-closed-side portion of the box as an assembly of five unitary vacuum-insulated panels, it is not desirable to do so because the relatively high thermal conductances of the seams between the panels would contribute significant amounts of heat leakage, relative to the leakage through the panels themselves. In contrast, the proposal would make it possible to reduce heat leakage by constructing the five-closed-side portion of the box plus the stationary portion (if any) of the sixth side as a single, seamless unit; the only remaining seam would be the edge seal around the door. The basic cross-sectional configuration of each side of a vacuum-insulated box according to the proposal would be that of a conventional vacuum-insulated panel: a low-density, porous core material filling a partially evacuated space between face sheets. However, neither the face sheets nor the core would be conventional. The face sheets would be opposite sides of a vacuum bag. The core material would be a flexible polymer-modified silica aerogel of the type described in Silica/Polymer and Silica/Polymer/Fiber Composite Aero - gels (MSC-23736) in this issue of NASA Tech Briefs. As noted in that article, the stiffness of this core material against compression is greater than that of prior aerogels. This is an important advantage because it translates to greater retention of thickness and, hence, of insulation performance when pressure is

Crude oil options market found to be efficient

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

Not Available

1992-08-17

This paper reports that the U.S. crude oil options market operates efficiently and does not overreact. The authors, with the JFK School of Government, studied the crude oil options market under a Department of Energy grant. The current market was created in November 1986 when the New York Mercantile Exchange introduced an options contract for delivery of West Texas intermediate crude futures. it has grown greatly since then.

Accelerator Vacuum Protection System

NASA Astrophysics Data System (ADS)

Barua, Pradip; Kothari, Ashok; Archunan, M.; Joshi, Rajan

2012-11-01

A new and elaborate automatic vacuum protection system using fast acting valve has been installed to avoid accidental venting of accelerator from experimental chamber side. To cover all the beam lines and to reduce the system cost, it has been installed at a common point from where all the seven beam lines originate. The signals are obtained by placing fast response pressure sensing gauges (HV SENSOR) near all the experimental stations. The closing time of the fast valve is 10 milli-second. The fast closing system protects only one vacuum line at a time. At IUAC, we have seven beam lines so one sensor was placed in each of the beam lines near experimental chamber and a multiplexer was incorporated into the fast closing system. At the time of experiment, the sensor of the active beam line is selected through the multiplexer and the Fast closing valve is interlocked with the selected sensor. As soon as the pressure sensor senses the pressure rise beyond a selected pressure, the signal is transferred and the fast valve closes within 10 to 12 millisecond.

Enzymatic lipophilization of epicatechin with free fatty acids and its effect on antioxidative capacity in crude camellia seed oil.

PubMed

Chen, Sa-Sa; Luo, Shui-Zhong; Zheng, Zhi; Zhao, Yan-Yan; Pang, Min; Jiang, Shao-Tong

2017-02-01

Crude camellia seed oil is rich in free fatty acids, which must be removed to produce an oil of acceptable quality. In the present study, we reduced the free fatty acid content of crude camellia seed oil by lipophilization of epicatechin with these free fatty acids in the presence of Candida antarctica lipase B (Novozym 435), and this may enhance the oxidative stability of the oil at the same time. The acid value of crude camellia seed oil reduced from 3.7 to 2.5 mgKOH g -1 after lipophilization. Gas chomatography-mass spectrometry analysis revealed that epicatechin oleate and epicatechin palmitate were synthesized in the lipophilized oil. The peroxide, p-anisidine, and total oxidation values during heating of the lipophilized oil were much lower than that of the crude oil and commercially available camellia seed oil, suggesting that lipophilized epicatechin derivatives could help enhance the oxidative stability of edible oil. The enzymatic process to lipophilize epicatechin with the free fatty acids in crude camellia seed oil described in the present study could decrease the acid value to meet the quality standards for commercial camellia seed oil and, at the same time, obtain a new edible camellia seed oil product with good oxidative stability. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Advanced performance of small diaphragm vacuum pumps through the use of mechatronics

NASA Astrophysics Data System (ADS)

Lachenmann, R.; Dirscherl, J.

Oil-free diaphragm vacuum pumps have proven to be the best way in vacuum generation for the chemical laboratory and they also find increasing use as backing pumps for modern wide-range turbo molecular pumps. The majority of vacuum pumps in practical use pump only a rather small percentage of their lifetime at full gas load. A pump backing a turbo molecular pump does not have to pump a significant gas load when the high-vacuum pump is running at ultimate vacuum pressure. Also, for a vacuum distillation the vacuum pump has to operate at full speed only at the beginning to lower the pressure inside the system to a vacuum level where evaporation starts. In a rather leak-tight system the distillation process continues by evaporating from the hot liquid and condensing at the cold condenser without the need of a mechanical vacuum pump. Rotational speed controlled diaphragm pumps are now available through progress in mechatronics and offer high pumping speed capability for fast pump-down cycles and precise pressure control for distillations. At low gas load the rotational speed can be reduced, improving maintenance intervals, power consumption, noise, vibration and - surprisingly - also ultimate pressure. The different behaviour in pumping speed and ultimate pressure of rotational speed controlled diaphragm pumps in comparison to constant-speed pumps is related to the mechanical properties of the valves and gas dynamics .

Microfabricated triggered vacuum switch

DOEpatents

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

2010-05-11

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

Wet/Dry Vacuum Cleaner

NASA Technical Reports Server (NTRS)

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

1995-01-01

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

Contents of lecithin and choline in crude drugs.

PubMed

Yamasaki, K; Kikuoka, M; Nishi, H; Kokusenya, Y; Miyamoto, T; Matsuo, M; Sato, T

1994-01-01

The determination of lecithin and choline in crude drugs was established by a combination of high performance liquid chromatography (HPLC) with electrochemical detector (ECD) and enzyme reaction. Lecithin in crude drugs extracted with a mixture of chloroform-methanol (2:1) at room temperature was hydrolyzed by phospholipase D. The hydrolyzate was injected to HPLC, and choline was separated from impurities by reverse phase column. The choline was converted to betaine and hydrogen peroxide by passing through column packed with immobilized choline oxidase. This hydrogen peroxide was detected by ECD. The peak area of hydrogen peroxide derived from lecithin was proportional to the concentration of lecithin from 0.10 to 1.52 microgram/ml. Choline in crude drugs was extracted with ethanol under reflux and determined under the same HPLC conditions as lecithin. The peak area of hydrogen peroxide derived from choline was proportional to the concentration of choline from 0.01 to 0.45 microgram/ml. The contents of lecithin and choline in 31 kinds of crude drugs were determined by these established methods. The results showed that Cervi Parvum Cornu, Kokurozin, Foenigraeci Semen and Psoraleae Semen contained more lecithin than other crude drugs, while Angelicae Radix, Foenigraeci Semen, Psoraleae Semen, and especially Hippocampus were found to contain more choline than other crude drugs.

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

NASA Astrophysics Data System (ADS)

Cheng, Shaoyong; Xiu, Shixin; Wang, Jimei; Shen, Zhengchao

2006-11-01

The greenhouse effect of SF6 is a great concern today. The development of high voltage vacuum circuit breakers becomes more important. The vacuum circuit breaker has minimum pollution to the environment. The vacuum interrupter is the key part of a vacuum circuit breaker. The interrupting characteristics in vacuum and arc-controlling technique are the main problems to be solved for a longer gap distance in developing high voltage vacuum interrupters. To understand the vacuum arc characteristics and provide effective technique to control vacuum arc in a long gap distance, the arc mode transition of a cup-type axial magnetic field electrode is observed by a high-speed charge coupled device (CCD) video camera under different gap distances while the arc voltage and arc current are recorded. The controlling ability of the axial magnetic field on vacuum arc obviously decreases when the gap distance is longer than 40 mm. The noise components and mean value of the arc voltage significantly increase. The effective method for controlling the vacuum arc characteristics is provided by long gap distances based on the test results. The test results can be used as a reference to develop high voltage and large capacity vacuum interrupters.

Radical Anions of Oxidized vs. Reduced Oxytocin: Influence of Disulfide Bridges on CID and Vacuum UV Photo-Fragmentation

NASA Astrophysics Data System (ADS)

MacAleese, Luke; Girod, Marion; Nahon, Laurent; Giuliani, Alexandre; Antoine, Rodolphe; Dugourd, Philippe

2018-06-01

The nonapeptide oxytocin (OT) is used as a model sulfur-containing peptide to study the damage induced by vacuum UV (VUV) radiations. In particular, the effect of the presence (or absence in reduced OT) of oxytocin's internal disulfide bridge is evaluated in terms of photo-fragmentation yield and nature of the photo-fragments. Intact, as well as reduced, OT is studied as dianions and radical anions. Radical anions are prepared and photo-fragmented in two-color experiments (UV + VUV) in a linear ion trap. VUV photo-fragmentation patterns are analyzed and compared, and radical-induced mechanisms are proposed. The effect of VUV is principally to ionize but secondary fragmentation is also observed. This secondary fragmentation seems to be considerably enabled by the initial position of the radical on the molecule. In particular, the possibility to form a radical on free cysteines seems to increase the susceptibility to VUV fragmentation. Interestingly, disulfide bridges, which are fundamental for protein structure, could also be responsible for an increased resistance to ionizing radiations. [Figure not available: see fulltext.

Wafer-Level Vacuum Packaging of Smart Sensors.

PubMed

Hilton, Allan; Temple, Dorota S

2016-10-31

The reach and impact of the Internet of Things will depend on the availability of low-cost, smart sensors-"low cost" for ubiquitous presence, and "smart" for connectivity and autonomy. By using wafer-level processes not only for the smart sensor fabrication and integration, but also for packaging, we can further greatly reduce the cost of sensor components and systems as well as further decrease their size and weight. This paper reviews the state-of-the-art in the wafer-level vacuum packaging technology of smart sensors. We describe the processes needed to create the wafer-scale vacuum microchambers, focusing on approaches that involve metal seals and that are compatible with the thermal budget of complementary metal-oxide semiconductor (CMOS) integrated circuits. We review choices of seal materials and structures that are available to a device designer, and present techniques used for the fabrication of metal seals on device and window wafers. We also analyze the deposition and activation of thin film getters needed to maintain vacuum in the ultra-small chambers, and the wafer-to-wafer bonding processes that form the hermetic seal. We discuss inherent trade-offs and challenges of each seal material set and the corresponding bonding processes. Finally, we identify areas for further research that could help broaden implementations of the wafer-level vacuum packaging technology.

Wafer-Level Vacuum Packaging of Smart Sensors

PubMed Central

Hilton, Allan; Temple, Dorota S.

2016-01-01

The reach and impact of the Internet of Things will depend on the availability of low-cost, smart sensors—“low cost” for ubiquitous presence, and “smart” for connectivity and autonomy. By using wafer-level processes not only for the smart sensor fabrication and integration, but also for packaging, we can further greatly reduce the cost of sensor components and systems as well as further decrease their size and weight. This paper reviews the state-of-the-art in the wafer-level vacuum packaging technology of smart sensors. We describe the processes needed to create the wafer-scale vacuum microchambers, focusing on approaches that involve metal seals and that are compatible with the thermal budget of complementary metal-oxide semiconductor (CMOS) integrated circuits. We review choices of seal materials and structures that are available to a device designer, and present techniques used for the fabrication of metal seals on device and window wafers. We also analyze the deposition and activation of thin film getters needed to maintain vacuum in the ultra-small chambers, and the wafer-to-wafer bonding processes that form the hermetic seal. We discuss inherent trade-offs and challenges of each seal material set and the corresponding bonding processes. Finally, we identify areas for further research that could help broaden implementations of the wafer-level vacuum packaging technology. PMID:27809249

[Adaptability of Helianthus annuus seedlings to crude oil pollution in soil and its improvement measures under salinization stress].

PubMed

Zhang, Jing-lei; Ci, Hua-cong; He, Xing-dong; Liang, Yu-ting; Zhao, Xuan; Sun, Hui-ting; Xie, Hong-tao

2015-11-01

To explore the adaptability of plant under salt stress to crude oil pollution of soil and improvement measures, a pot experiment of Helianthus annuus seedlings was conducted using orthogonal experiment method with crude oil-sodium chloride-desulfurization gypsum and cinder-zeolite-desulfurization gypsum-sawdust. The results showed that, with the increase of soil crude oil concentration, the relative growth rate (RGR) of plant height, RGR of aboveground biomass and root N: P ratios of H. annuus seedlings decreased significantly, while the activity of SOD and CAT increased at first and then decreased significantly. The RGR of plant height and aboveground biomass significantly increased (P < 0.05), while the activity of SOD decreased gradually with the increase of the volume fraction of sawdust, indicating that sawdust had the most significant effect in comparison with cinder, zeolite, desulfurization gypsum under salinization condition. The crude oil pollution of soil could decrease the relative growth rate of H. annuus seedling, and sawdust could reduce the influence of crude oil pollution on plant growth under salt stress.

Potential biodegradation of crude petroleum oil by newly isolated halotolerant microbial strains from polluted Red Sea area.

PubMed

Shetaia, Yousseria M H; El Khalik, Wafaa A A; Mohamed, Tarek M; Farahat, Laila A; ElMekawy, Ahmed

2016-10-15

Two microbial isolates from oil polluted Red Sea water in Egypt, designated as RS-Y1 and RS-F3, were found capable of degrading Belayim mix (BX) crude oil. Strains RS-Y1 and RS-F3 were assigned to the genera Lipomyces tetrasporus and Paecilomyces variotii based on their morphological and physiological characteristics. Both isolates were compared for the biodegradation of crude petroleum-oil hydrocarbons in basal salt medium supplemented with 5% (w/v) of BX-crude oil. Gas chromatography profile showed that the biodegradation of total petroleum hydrocarbons (TPHs) inoculated with L. tetrasporus (68.3%) and P. variotii (58.15%) along with their consortium (66%) significantly reduced TPHs levels as compared to the control after 30days. L. tetrasporus (44.5%) was more effective than P. variotii strain (32.89%) in reducing the unresolved complex mixtures (UCM) content from the medium. Both isolates exhibited a strong growth over a wide range of salinity (5-45g/L NaCl). Copyright © 2016 Elsevier Ltd. All rights reserved.

Vacuum probe surface sampler

NASA Technical Reports Server (NTRS)

Zahlava, B. A. (Inventor)

1973-01-01

A vacuum probe surface sampler is described for rapidly sampling relatively large surface areas which possess relatively light loading densities of micro-organism, drug particles or the like. A vacuum head with a hollow handle connected to a suitable vacuum source is frictionally attached to a cone assembly terminating in a flared tip adapted to be passed over the surface to be sampled. A fine mesh screen carried by the vacuum head provides support for a membrane filter which collects the microorganisms or other particles. The head assembly is easily removed from the cone assembly without contacting the cone assembly with human hands.

Removal of crude oil polycyclic aromatic hydrocarbons via organoclay-microbe-oil interactions.

PubMed

Ugochukwu, Uzochukwu C; Fialips, Claire I

2017-05-01

Clay minerals are quite vital in biogeochemical processes but the effect of organo-clays in the microbial degradation of crude oil polycyclic aromatic hydrocarbons is not well understood. The role of organo-saponite and organo-montmorillonite in comparison with the unmodified clays in crude oil polycyclic aromatic hydrocarbons (PAHs) removal via adsorption and biodegradation was studied by carrying out microcosm experiments in aqueous clay/oil systems with a hydrocarbon degrading microbial community that is predominantly alcanivorax spp. Montmorillonite and saponite samples were treated with didecyldimethylammonium bromide to produce organo-montmorillonite and organo-saponite used in this study. Obtained results indicate that clays with high cation exchange capacity (CEC) such as montmorillonite produced organo-clay (organomontmorillonite) that was not stimulatory to biodegradation of crude oil polycyclic aromatic compounds, especially the low molecular weight (LMW) ones, such as dimethylnaphthalenes. It is suggested that interaction between the organic phase of the organo-clay and the crude oil PAHs which is hydrophobic in nature must have reduced the availability of the polycyclic aromatic hydrocarbons for biodegradation. Organo-saponite did not enhance the microbial degradation of dimethylnaphthalenes but enhanced the biodegradation of some other PAHs such as phenanthrene. The unmodified montmorillonite enhanced the microbial degradation of the PAHs and is most likely to have done so as a result of its high surface area that allows the accumulation of microbes and nutrients enhancing their contact. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

PubMed

Mengelkoch, Larry J; Clark, Kirby

2006-03-01

The purpose of this study was to evaluate two types of industrial vacuum cleaners, in terms of cleaning rates, energy expenditure, and perceived exertion. Twelve industrial cleaners (six males and six females, age 28-39 yr) performed two 1-h vacuuming tasks with an upright vacuum cleaner (UVC) and a backpack vacuum cleaner (BPVC). Measures for oxygen uptake (VO2) and ratings of perceived exertion (RPE) were collected continuously during the 1-h vacuuming tasks. Cleaning rates for the UVC and BPVC were 7.23 and 14.98 m2min(-1), respectively. On a separate day subjects performed a maximal treadmill exercise test to determine their maximal aerobic capacity (peak VO2). Average absolute energy costs (in Metabolic equivalents), relative energy costs of the vacuum task compared to the subjects' maximal aerobic capacity (% peak VO2), and RPE responses for the 1-h vacuuming tasks were similar between vacuum cleaners, but % peak VO2 and RPE values differed between genders. These results indicate that the BPVC was more efficient than the UVC. With the BPVC, experienced workers vacuumed at a cleaning rate 2.07 times greater than the UVC and had similar levels of energy expenditure and perceived effort, compared to the slower cleaning rate with the UVC.

Value-added uses for crude glycerol--a byproduct of biodiesel production

PubMed Central

2012-01-01

Biodiesel is a promising alternative, and renewable, fuel. As its production increases, so does production of the principle co-product, crude glycerol. The effective utilization of crude glycerol will contribute to the viability of biodiesel. In this review, composition and quality factors of crude glycerol are discussed. The value-added utilization opportunities of crude glycerol are reviewed. The majority of crude glycerol is used as feedstock for production of other value-added chemicals, followed by animal feeds. PMID:22413907

Overcoming bottlenecks of enzymatic biofuel cell cathodes: crude fungal culture supernatant can help to extend lifetime and reduce cost.

PubMed

Sané, Sabine; Jolivalt, Claude; Mittler, Gerhard; Nielsen, Peter J; Rubenwolf, Stefanie; Zengerle, Roland; Kerzenmacher, Sven

2013-07-01

Enzymatic biofuel cells (BFCs) show great potential for the direct conversion of biochemically stored energy from renewable biomass resources into electricity. However, enzyme purification is time-consuming and expensive. Furthermore, the long-term use of enzymatic BFCs is hindered by enzyme degradation, which limits their lifetime to only a few weeks. We show, for the first time, that crude culture supernatant from enzyme-secreting microorganisms (Trametes versicolor) can be used without further treatment to supply the enzyme laccase to the cathode of a mediatorless BFC. Polarization curves show that there is no significant difference in the cathode performance when using crude supernatant that contains laccase compared to purified laccase in culture medium or buffer solution. Furthermore, we demonstrate that the oxygen reduction activity of this enzymatic cathode can be sustained over a period of at least 120 days by periodic resupply of crude culture supernatant. This is more than five times longer than control cathodes without the resupply of culture supernatant. During the operation period of 120 days, no progressive loss of potential is observed, which suggests that significantly longer lifetimes than shown in this work may be possible. Our results demonstrate the possibility to establish simple, cost efficient, and mediatorless enzymatic BFC cathodes that do not require expensive enzyme purification procedures. Furthermore, they show the feasibility of an enzymatic BFC with an extended lifetime, in which self-replicating microorganisms provide the electrode with catalytically active enzymes in a continuous or periodic manner. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improving Lowland Rice (O. sativa L. cv. MR219) Plant Growth Variables, Nutrients Uptake, and Nutrients Recovery Using Crude Humic Substances.

PubMed

Palanivell, Perumal; Ahmed, Osumanu Haruna; Ab Majid, Nik Muhamad; Jalloh, Mohamadu Boyie; Susilawati, Kasim

2015-01-01

High cation exchange capacity and organic matter content of crude humic substances from compost could be exploited to reduce ammonia loss from urea and to as well improve rice growth and soil chemical properties for efficient nutrients utilization in lowland rice cultivation. Close-dynamic air flow system was used to determine the effects of crude humic substances on ammonia volatilization. A pot experiment was conducted to determine the effects of crude humic substances on rice plant growth, nutrients uptake, nutrients recovery, and soil chemical properties using an acid soil mixed with three rates of crude humic substances (20, 40, and 60 g pot(-1)). Standard procedures were used to evaluate rice plant dry matter production, nutrients uptake, nutrients recovery, and soil chemical properties. Application of crude humic substances increased ammonia volatilization. However, the lowest rate of crude humic substances (20 g pot(-1)) significantly improved total dry matter, nutrients uptake, nutrients recovery, and soil nutrients availability compared with crude humic substances (40 and 60 g pot(-1)) and the normal fertilization. Apart from improving growth of rice plants, crude humic substances can be used to ameliorate acid soils in rice cultivation. The findings of this study are being validated in our ongoing field trials.

Improving Lowland Rice (O. sativa L. cv. MR219) Plant Growth Variables, Nutrients Uptake, and Nutrients Recovery Using Crude Humic Substances

PubMed Central

Palanivell, Perumal; Ahmed, Osumanu Haruna; Ab Majid, Nik Muhamad; Jalloh, Mohamadu Boyie; Susilawati, Kasim

2015-01-01

High cation exchange capacity and organic matter content of crude humic substances from compost could be exploited to reduce ammonia loss from urea and to as well improve rice growth and soil chemical properties for efficient nutrients utilization in lowland rice cultivation. Close-dynamic air flow system was used to determine the effects of crude humic substances on ammonia volatilization. A pot experiment was conducted to determine the effects of crude humic substances on rice plant growth, nutrients uptake, nutrients recovery, and soil chemical properties using an acid soil mixed with three rates of crude humic substances (20, 40, and 60 g pot−1). Standard procedures were used to evaluate rice plant dry matter production, nutrients uptake, nutrients recovery, and soil chemical properties. Application of crude humic substances increased ammonia volatilization. However, the lowest rate of crude humic substances (20 g pot−1) significantly improved total dry matter, nutrients uptake, nutrients recovery, and soil nutrients availability compared with crude humic substances (40 and 60 g pot−1) and the normal fertilization. Apart from improving growth of rice plants, crude humic substances can be used to ameliorate acid soils in rice cultivation. The findings of this study are being validated in our ongoing field trials. PMID:25977938

Guatemala switch to crude saves over $1 million a month

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

de Biasi, V.

1980-03-01

In a two-step program designed to reduce fuel costs and improve operating efficiency, Empresa Electrica de Guatemala has modified two General Electric PG 5341 gas turbines at Laguna to run on crude oil and installed heat recovery equipment for repowering two existing steam turbines. The gas turbines, nominally rated at around 19,000 kW for base load operation at 70/sup 0/F average ambient temperature and 4000 feet altitude, were installed in 1977-78 as a base load backup to hydro power during the dry season. Original plan was to put them into immediate service as simple cycle units and then convert tomore » combined cycle operation. Priorities were shifted to switch over from distillate to crude oil firing before going ahead with the combined cycle istallation. Their economic evaluation showed the initial investment would be paid off in a few months by the savings in fuel costs.« less

Application of Biosurfactants Produced by Pseudomonas putida using Crude Palm Oil (CPO) as Substrate for Crude Oil Recovery using Batch Method

NASA Astrophysics Data System (ADS)

Suryanti, V.; Handayani, D. S.; Masykur, A.; Septyaningsih, I.

2018-03-01

The application of biosurfactants which have been produced by Pseudomonas putida in nutrient broth medium supplemented with NaCl and crude palm oil (CPO) for oil recovery has been evaluated. The crude and purified biosurfactants have been examined for oil recovery from a laboratory oil-contaminated sand in agitated flask (batch method). Two synthetic surfactants and water as control was also performed for oil recovery as comparisons. Using batch method, the results showed that removing ability of crude oil from the oil-contaminated sand by purified and crude biosurfactants were 79.40±3.10 and 46.84±2.23 %, respectively. On other hand, the recoveries obtained with the SDS, Triton X-100 and water were 94.33±0.47, 74.84±7.39 and 34.42±1.21%respectively.

A radiation hard vacuum switch

DOEpatents

Boettcher, G.E.

1988-07-19

A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction. 3 figs.

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

PubMed

Han, Young Keun; Miller, Kevin M

2009-08-01

To compare vacuum rise time, vacuum limit accuracy, and occlusion break surge of 3 new phacoemulsification machines. Jules Stein Eye Institute and Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California, USA. The vacuum rise time under normal and enhanced aspiration modes, vacuum limit accuracy, and occlusion break surge of the Infiniti Vision System, Stellaris Vision Enhancement System, and WhiteStar Signature Phacoemulsification System were tested. Vacuum rise time and limit accuracy were measured at limit settings of 400 mm Hg and 600 mm Hg. Surge area was recorded at vacuum limit settings of 200 mm Hg, 300 mm Hg, 400 mm Hg, and 500 mm Hg. The Infiniti had the fastest vacuum rise times under normal and enhanced aspiration modes. At 4 seconds, the vacuum limit accuracy was greatest with the Infiniti at the 400 mm Hg limit and the Signature at the 600 mm Hg limit. The Stellaris did not reach either vacuum target. The Infiniti performed better than the other 2 machines during testing of occlusion break surge at all vacuum limit settings above 200 mm Hg. Under controlled laboratory test conditions, the Infiniti had the fastest vacuum rise time, greatest vacuum limit accuracy at 400 mm Hg, and least occlusion break surge. These results can be explained by the lower compliance of the Infiniti system.

Natural seepage of crude oil into the marine environment

USGS Publications Warehouse

Kvenvolden, K.A.; Cooper, C.K.

2003-01-01

Recent global estimates of crude-oil seepage rates suggest that about 47% of crude oil currently entering the marine environment is from natural seeps, whereas 53% results from leaks and spills during the extraction, transportation, refining, storage, and utilization of petroleum. The amount of natural crude-oil seepage is currently estimated to be 600,000 metric tons per year, with a range of uncertainty of 200,000 to 2,000,000 metric tons per year. Thus, natural oil seeps may be the single most important source of oil that enters the ocean, exceeding each of the various sources of crude oil that enters the ocean through its exploitation by humankind.

Vacuum pull down method for an enhanced bonding process

DOEpatents

Davidson, James C.; Balch, Joseph W.

1999-01-01

A process for effectively bonding arbitrary size or shape substrates. The process incorporates vacuum pull down techniques to ensure uniform surface contact during the bonding process. The essence of the process for bonding substrates, such as glass, plastic, or alloys, etc., which have a moderate melting point with a gradual softening point curve, involves the application of an active vacuum source to evacuate interstices between the substrates while at the same time providing a positive force to hold the parts to be bonded in contact. This enables increasing the temperature of the bonding process to ensure that the softening point has been reached and small void areas are filled and come in contact with the opposing substrate. The process is most effective where at least one of the two plates or substrates contain channels or grooves that can be used to apply vacuum between the plates or substrates during the thermal bonding cycle. Also, it is beneficial to provide a vacuum groove or channel near the perimeter of the plates or substrates to ensure bonding of the perimeter of the plates or substrates and reduce the unbonded regions inside the interior region of the plates or substrates.

Air bearing vacuum seal assembly

DOEpatents

Booth, Rex

1978-01-01

An air bearing vacuum seal assembly capable of rotating at the speed of several thousand revolutions per minute using an air cushion to prevent the rotating and stationary parts from touching, and a two stage differential pumping arrangement to maintain the pressure gradient between the air cushion and the vacuum so that the leak rate into the vacuum is, for example, less than 1 .times. 10.sup.-4 Pa m.sup.3 /s. The air bearing vacuum seal has particular application for mounting rotating targets to an evacuated accelerator beam tube for bombardment of the targets with high-power charged particle beams in vacuum.

Extraction, Antimicrobial, and Antioxidant Activities of Crude Polysaccharides from the Wood Ear Medicinal Mushroom Auricularia auricula-judae (Higher Basidiomycetes).

PubMed

Cai, Ming; Lin, Yang; Luo, Yin-long; Liang, Han-hua; Sun, Pei-long

2015-01-01

In this study, crude polysaccharides of culinary-medicinal mushroom Auricularia auricular-judae were extracted by hot water extraction and alcohol precipitation, and their antimicrobial and antioxidant activities were investigated. An optimum extraction condition was obtained at a ratio of liquid to solid 70 mL/g, temperature 90°C, time 4 h and extraction number 4. Accordingly, the best yield of crude polysaccharides was 6.89% with 76.12% in purity. Some bacteria and fungi were used for antimicrobial studies. It was found that crude A. auricula-judae had great antimicrobial activities against Escherichia coli and Staphylococcus aureus, but no activities on the others. The inhibitory diameters of antimicrobial zones for the two were 5.55 ± 0.182 and 9.84 ± 0.076 mm, respectively. Moreover, crude A. auricula-judae had significant antioxidant activities in scavenging free radicals, reducing power assays, and Fe2+ chelating ability assay. Results revealed that crude A. auricula-judae has a great potential as antimicrobial and antioxidant, and it can be a supplementary food for human health.

Vacuum frying as a route to produce novel snacks with desired quality attributes according to new health trends.

PubMed

Dueik, V; Bouchon, P

2011-03-01

Consumers look for products that contribute to their wellness and health, however, even health-conscious consumers are not willing to sacrifice organoleptic properties, and intense full-flavor snacks remain an important trend. The objective of this study was to examine most important quality parameters of vacuum (1.92 inHg) and atmospheric-fried carrot, potato, and apple slices to determine specific advantages of vacuum technology. Slices were fried using equivalent thermal driving forces, maintaining a constant difference between oil temperature and the boiling point of water at the working pressure (ΔT = 60 and 80 °C). This resulted in frying temperatures of 160 and 180 °C, and 98 and 118 °C, for atmospheric and vacuum frying, respectively. Vacuum-fried carrot and potato chips absorbed about 50% less oil than atmospheric-fried chips, whereas vacuum-fried apple chips reduced oil absorption by 25%. Total carotenoids and ascorbic acid (AA) were greatly preserved during vacuum frying. Carrot chips vacuum fried at 98 °C retained about 90% of total carotenoids, whereas potato and apple slices vacuum fried at 98 °C, preserved around 95% of their initial AA content. Interestingly, results showed that the antioxidant capacity of chips may be related to both the presence of natural antioxidants and brown pigments developed at elevated temperatures. A way to reduce detrimental effects of deep-fat frying is through operating-pressure reduction, the essence behind vacuum deep-fat frying. In this way, it is possible to remove product moisture at a low temperature in a low-oxygen environment. The objective of this research was to study the effect of oil temperature reduction when vacuum frying traditional (potatoes) and nontraditional products (carrots and apples) on most important quality attributes (vitamins, color, and oil uptake). Results are promising and show that vacuum frying can be an alternative to produce nutritious and novel snacks with desired quality

Vacuum-Gauge Connection For Shipping Container

NASA Technical Reports Server (NTRS)

Henry, Robert H.

1990-01-01

External connector enables measurement of vacuum in stored part. Remote-readout connector added to shipping container and connected to thermo-couple vacuum gauge in vacuum-insulated cryogenic line packed in container. Enables monitoring of condition of vacuum without opening container.

Flux tubes and coherence length in the SU(3) vacuum

NASA Astrophysics Data System (ADS)

Cea, P.; Cosmai, L.; Cuteri, F.; Papa, A.

An estimate of the London penetration and coherence lengths in the vacuum of the SU(3) pure gauge theory is given downstream an analysis of the transverse profile of the chromoelectric flux tubes. Within ordinary superconductivity, a simple variational model for the magnitude of the normalized order parameter of an isolated vortex produces an analytic expression for magnetic field and supercurrent density. In the picture of SU(3) vacuum as dual superconductor, this expression provides us with the function that fits the chromoelectric field data. The smearing procedure is used in order to reduce noise.

Research on thermal conductivity of HGMs at vacuum in room temperature

NASA Astrophysics Data System (ADS)

Wang, Ping; Liao, Bin; An, Zhenguo; Yan, Kaiqi; Zhang, Jingjie

2018-05-01

Hollow glass microspheres (HGMs) can be used as thermal insulation materials owing to its hollow structure which brings excellent thermal insulation property and low density. At present, most researches on thermal conductivity of HGMs are focused on polymer matrix/HGMs composite materials. However, thermal conductivity of HGMs at vacuum in room temperature has rarely been investigated. In this work, thermal conductivity of six types of HGMs (T17 (0.17g/cm3), T20 (0.20g/cm3), T22 (0.22g/cm3), T25 (0.25g/cm3), T32 (0.32g/cm3) and T40 (0.40g/cm3)) at vacuum in room temperature were calculated by heat transfer of solid conduction and radiation. The calculation results showed that thermal conductivity of HGMs would be decreased by an order of magnitude compared with no vacuum. In order to verify the calculation and study vacuum thermal insulation properties of HGMs, thermal conductivity of above-mentioned HGMs at no vacuum and high vacuum in room temperature were measured by a self-made thermal conductivity measuring apparatus which was based on the transient plane source (TPS) method. The experimental results showed that thermal conductivity of HGMs were in the range of 4.2030E-02 to 6.3300E-02 W/m.K (at no vacuum) and 3.8160E-03 to 4.9660E-03 W/m.K (at high vacuum). The results indicated that experimental thermal conductivity was consistent with the calculation results and both of them were all decreased by 8-13 times at vacuum compared with no vacuum. In addition, the relationship with physical properties and thermal conductivity of HGMs has been discussed in detail. In conclusion, HGMs possess excellent thermal insulation performance at high vacuum in room temperature and have potential to further reduce thermal conductivity at the same conditions.

Cold cathode vacuum discharge tube

DOEpatents

Boettcher, Gordon E.

1998-01-01

A cold cathode vacuum discharge tube, and method for making same, with an interior surface of the trigger probe coated with carbon deposited by carbon vapor deposition (CVD) or diamond-like carbon (DLC) deposition. Preferably a solid graphite insert is employed in the probe-cathode structure in place of an aluminum bushing employed in the prior art. The CVD or DLC probe face is laser scribed to allow resistance trimming to match available trigger voltage signals and to reduce electrical aging.

NSLS II Vacuum System

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

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

2009-09-13

National Synchrotron Light Source II, being constructed at Brookhaven, is a 3-GeV, 500 mA, 3rd generation synchrotron radiation facility with ultra low emittance electron beams. The storage ring vacuum system has a circumference of 792 m and consists of over 250 vacuum chambers with a simulated average operating pressure of less than 1 x 10{sup -9} mbar. A summary of the update design of the vacuum system including girder supports of the chambers, gauges, vacuum pumps, bellows, beam position monitors and simulation of the average pressure will be shown. A brief description of the techniques and procedures for cleaning andmore » mounting the chambers are given.« less

Future global crude oil supply

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

Ivanhoe, L.F.

Inexpensive crude oil fuels the world's economies and armies. In 1986, for the first time, the global production of crude oil and natural liquids exceeded new reserves added. Proved oil reserves at the end of 1985 stood 707.6 billion bbl (BBO), but declined to 703.1 BBO by the end of 1986. The 1986 reserve decrease, 4.5 BBO, was 20.4% of total global production of 22.0 BBO. This handwriting on the wall is very bad news. The world's recoverable crude oil and natural gas liquids discovered through 1985 totaled 1258 BBO, including cumulative production of 551 BBO and 707 BBO ofmore » reserves. At current production rates, half of all discovered oil will have been burned up by 1989. Timing of the end of our oil age can be extrapolated from a modified Hubbert curve, with future production resembling a mirror image of past production. The watershed beginning of the inevitable decline in global crude oil supplies can be expected in the late 1990s, although the date may be over 30 years later in some super-oily Organization of Petroleum Exporting Countries (OPEC). Clearly the day of reckoning will be postponed by any new oil discoveries. These will probably be distributed much as are the present global reserves (e.g., 68% OPEC; 11% USSR and China; 21% rest of world). Of this 56% will be in the Persian Gulf area. Giant fields (more than 0.5 BBO reserves) contain 75% of the world's reserves. Discoveries of oil in the globe's 320 known giant fields peaked at 125 BBO during the period 1961-1965, after which giant field discoveries plunged to only 10 BBO during 1981-1985. Henceforth, they should expect to find few giant whales (but many minnows) in the non-OPEC world's fished-out basins. Every new field will help as global crude oil supplies dwindle. Therefore, it is essential that all large prospects outside the Persian Gulf be tested promptly, so the oil-importing nations will known what size of non-OPEC reserves are available.« less

15 CFR 754.3 - Petroleum products not including crude oil.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 15 Commerce and Foreign Trade 2 2011-01-01 2011-01-01 false Petroleum products not including crude... SUPPLY CONTROLS § 754.3 Petroleum products not including crude oil. (a) License requirement. As indicated... required to all destinations, including Canada, for the export of petroleum products, excluding crude oil...

15 CFR 754.3 - Petroleum products not including crude oil.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Petroleum products not including crude... SUPPLY CONTROLS § 754.3 Petroleum products not including crude oil. (a) License requirement. As indicated... required to all destinations, including Canada, for the export of petroleum products, excluding crude oil...

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

NASA Astrophysics Data System (ADS)

Lee, T. J.; Lee, K. S., , Dr; Lee, S. K.

2017-12-01

One of the most important factors in measuring effective porosity by vacuum saturation method is that the air in the pore space can be fully substituted by water during the vacuum saturation process. International Society of Rock Mechanics (ISRM) suggests vacuuming a rock sample submerged in the water, while American Society of Test and Materials (ASTM) vacuuming the sample and water separately and then pour the water to the sample. In this study, we call the former wet-type vacuum saturation (WVS) method and the latter dry-type vacuum saturation (DVS) method, and compare the effective porosity measured by the two different vacuum saturation processes. For that purpose, a vacuum saturation system has been developed, which can support both WVS and DVS by only changing the process by programming. Comparison of effective porosity has been made for a cement mortar and rock samples. As a result, DVS can substitute more void volume to water than WVS, which in turn insists that DVS can provide more exact value of effective porosity than WVS.

4. TROJAN MILL, DETAIL OF CRUDE ORE BINS FROM NORTH, ...

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

4. TROJAN MILL, DETAIL OF CRUDE ORE BINS FROM NORTH, c. 1912. SHOWS TIMBER FRAMING UNDER CONSTRUCTION FOR EAST AND WEST CRUDE ORE BINS AT PREVIOUS LOCATION OF CRUSHER HOUSE, AND SNOW SHED PRESENT OVER SOUTH CRUDE ORE BIN WITH PHASE CHANGE IN SNOW SHED CONSTRUCTION INDICATED AT EAST END OF EAST CRUDE ORE BIN. THIS PHOTOGRAPH IS THE FIRST IMAGE OF THE MACHINE SHOP, UPPER LEFT CORNER. CREDIT JW. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Value-added processing of crude glycerol into chemicals and polymers.

PubMed

Luo, Xiaolan; Ge, Xumeng; Cui, Shaoqing; Li, Yebo

2016-09-01

Crude glycerol is a low-value byproduct which is primarily obtained from the biodiesel production process. Its composition is significantly different from that of pure glycerol. Crude glycerol usually contains various impurities, such as water, methanol, soap, fatty acids, and fatty acid methyl esters. Considerable efforts have been devoted to finding applications for converting crude glycerol into high-value products, such as biofuels, chemicals, polymers, and animal feed, to improve the economic viability of the biodiesel industry and overcome environmental challenges associated with crude glycerol disposal. This article reviews recent advances of biological and chemical technologies for value-added processing of crude glycerol into chemicals and polymers, and provides strategies for addressing production challenges. Copyright © 2016 Elsevier Ltd. All rights reserved.

Toxicity of oil dispersant, crude oil and dispersed crude oil to a marine amphipod and gastropod

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

Gulec, I.; Holdway, D.A.

1995-12-31

The importance of appropriate oil spill remedial action was emphasized during the recent Iron Barron oil spill off of the Tamar river in North Tasmania. One important potential oil spill response is dispersion, but little information exists on the toxicity of dispersants and dispersed oil to Australian marine species. This research was undertaken to assess the acute toxicity of Corexit 9527 (a widely used dispersant), water accommodated fractions of Bass Strait crude oil and dispersed Bass Strait crude oil, to the saltwater amphipod, Allorchestes compressa under semi-static conditions. Acute 96 h LC50`s were determined for each toxicant as well asmore » for the reference toxicants sodium dodecyl sulfate (SDS) and zinc sulfate. Sublethal bioassays were undertaken for the same 3 toxicants utilizing the marines and snail Polinices conicus as the test species. No-observed-effect-concentrations (NOEC) and lowest-observed-effect-concentrations (LOEC) were determined using ANOVA while EC50`s and EC0`s were calculated using regression analysis. Mean acute 96 h LC50 (S.E.) values for A. compressa exposed to SDS and zinc sulfate were 3.6 mg/l (0.28) and 41.6 mg/l (9.01) respectively. EC50 (S.E.) concentrations for P. conicus exposed to SDS and zinc sulfate for 30 minutes were 44.7 mg/l and 246 mg/l respectively using burying behavior as an endpoint. These sublethal EC50`s were reduced to 20.7 mg/l for SDS and 23.5 mg/l for zinc sulfate following 24 hours of exposure.« less

Study on vacuum packaging reliability of micromachined quartz tuning fork gyroscopes

NASA Astrophysics Data System (ADS)

Fan, Maoyan; Zhang, Lifang

2017-09-01

Packaging technology of the micromachined quartz tuning fork gyroscopes by vacuum welding has been experimentally studied. The performance of quartz tuning fork is influenced by the encapsulation shell, encapsulation method and fixation of forks. Alloy solder thick film is widely used in the package to avoid the damage of the chip structure by the heat resistance and hot temperature, and this can improve the device performance and welding reliability. The results show that the bases and the lids plated with gold and nickel can significantly improve the airtightness and reliability of the vacuum package. Vacuum packaging is an effective method to reduce the vibration damping, improve the quality factor and further enhance the performance. The threshold can be improved nearly by 10 times.

North Sea Emerald crude oil assayed

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

Rhodes, A.K.

1991-09-16

This book reports on an analysis of crude from Emerald field, 70 miles east of the Shetland Islands in the British North Sea, which shows that the crude is much heavier than typical North Sea crude. Elements of the long- delayed project appear to be in place, but production has not yet begun. Plans calls for producing the field at a rate of 30,000-40,000 b/d from a floating storage unit. Sovereign Oil and Gas plc has completed and fully tested seven production wells and four injectors in the marginal Emerald oil field. All flow lines are in place and themore » floating storage unit is ready to be installed. Production from Emerald will be sold to Neste Oy of Finland, at a minimum price of $17.90/bbl for Sullom Voe. Increases in spot prices above that level will be shared equally by the owners and purchaser.« less

State-of-the-art of recycling e-wastes by vacuum metallurgy separation.

PubMed

Zhan, Lu; Xu, Zhenming

2014-12-16

In recent era, more and more electric and electronic equipment wastes (e-wastes) are generated that contain both toxic and valuable materials in them. Most studies focus on the extraction of valuable metals like Au, Ag from e-wastes. However, the recycling of metals such as Pb, Cd, Zn, and organics has not attracted enough attentions. Vacuum metallurgy separation (VMS) processes can reduce pollution significantly using vacuum technique. It can effectively recycle heavy metals and organics from e-wastes in an environmentally friendly way, which is beneficial for both preventing the heavy metal contaminations and the sustainable development of resources. VMS can be classified into several methods, such as vacuum evaporation, vacuum carbon reduction and vacuum pyrolysis. This paper respectively reviews the state-of-art of these methods applied to recycling heavy metals and organics from several kinds of e-wastes. The method principle, equipment used, separating process, optimized operating parameters and recycling mechanism of each case are illustrated in details. The perspectives on the further development of e-wastes recycling by VMS are also presented.

Brine-in-crude-oil emulsions at the Strategic Petroleum Reserve

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

Nemer, Martin B.; Lord, David L.; MacDonald, Terry L.

2013-10-01

Metastable water-in-crude-oil emulsion formation could occur in a Strategic Petroleum Reserve (SPR) cavern if water were to flow into the crude-oil layer at a sufficient rate. Such a situation could arise during a drawdown from a cavern with a broken-hanging brine string. A high asphaltene content (> 1.5 wt %) of the crude oil provides the strongest predictor of whether a metastable water-in-crude-oil emulsion will form. However there are many crude oils with an asphaltene content > 1.5 wt % that don't form stable emulsions, but few with a low asphaltene content that do form stable emulsions. Most of themore » oils that form stable emulsions are "sour" by SPR standards indicating they contain total sulfur > 0.50 wt %.« less

Life cycle environmental impacts of vacuum cleaners and the effects of European regulation.

PubMed

Gallego-Schmid, Alejandro; Mendoza, Joan Manuel F; Jeswani, Harish Kumar; Azapagic, Adisa

2016-07-15

Energy efficiency of vacuum cleaners has been declining over the past decades while at the same time their number in Europe has been increasing. The European Commission has recently adopted an eco-design regulation to improve the environmental performance of vacuum cleaners. In addition to the existing directive on waste electrical and electronic equipment (WEEE), the regulation could potentially have significant effects on the environmental performance of vacuum cleaners. However, the scale of the effects is currently unknown, beyond scant information on greenhouse gas emissions. Thus, this paper considers for the first time life cycle environmental impacts of vacuum cleaners and the effects of the implementation of these regulations at the European level. The effects of electricity decarbonisation, product lifetime and end-of-life disposal options are also considered. The results suggest that the implementation of the eco-design regulation alone will reduce significantly the impacts from vacuum cleaners (37%-44%) by 2020 compared with current situation. If business as usual continued and the regulation was not implemented, the impacts would be 82%-109% higher by 2020 compared to the impacts with the implementation of the regulation. Improvements associated with the implementation of the WEEE directive will be much smaller (<1% in 2020). However, if the WEEE directive did not exist, then the impacts would be 2%-21% higher by 2020 relative to the impacts with the implementation of the directive. Further improvements in most impacts (6%-20%) could be achieved by decarbonising the electricity mix. Therefore, energy efficiency measures must be accompanied by appropriate actions to reduce the environmental impacts of electricity generation; otherwise, the benefits of improved energy efficiency could be limited. Moreover, because of expected lower life expectancy of vacuum cleaners and limited availability of some raw materials, the eco-design regulation should be

Cold cathode vacuum discharge tube

DOEpatents

Boettcher, G.E.

1998-03-10

A cold cathode vacuum discharge tube, and method for making same, are disclosed with an interior surface of the trigger probe coated with carbon deposited by carbon vapor deposition (CVD) or diamond-like carbon (DLC) deposition. Preferably a solid graphite insert is employed in the probe-cathode structure in place of an aluminum bushing employed in the prior art. The CVD or DLC probe face is laser scribed to allow resistance trimming to match available trigger voltage signals and to reduce electrical aging. 15 figs.

Cold cathode vacuum discharge tube

DOEpatents

Boettcher, G.E.

1998-04-14

A cold cathode vacuum discharge tube, and method for making same, with an interior surface of the trigger probe coated with carbon deposited by chemical vapor deposition (CVD) or diamond-like carbon (DLC) deposition are disclosed. Preferably a solid graphite insert is employed in the probe-cathode structure in place of an aluminum bushing employed in the prior art. The CVD or DLC probe face is laser scribed to allow resistance trimming to match available trigger voltage signals and to reduce electrical aging. 14 figs.

Removing antimony from waste lead storage batteries alloy by vacuum displacement reaction technology.

PubMed

Liu, Tiantian; Qiu, Keqiang

2018-04-05

With the wide application of lead acid battery, spent lead acid battery has become a serious problem to environmental protection and human health. Though spent battery can be a contaminant if not handled properly, it is also an important resource to obtain refined lead. Nowadays, the Sb-content in lead storage batteries is about 0.5-3 wt%, which is higher than the Sb-content in the crude lead. However, there are few reports about the process of removing antimony from high-antimony lead bullion. In this study, vacuum displacement reaction technology, a new process for removing antimony from high-antimony lead melts, was investigated. During this process, lead oxide was added to the system and antimony from lead melts was converted into antimony trioxide, which easily was evaporated under vacuum so that antimony was removed from lead melts. The experimental results demonstrated that Sb-content in lead melts decreased from 2.5% to 23 ppm under following conditions: mass ratio of PbO/lead bullion of 0.33, residual gas pressure of 30 Pa, melt temperature of 840 °C, reaction time of 60 min. The distillate gotten can be used as by-product to produce antimony white. Moreover, this study is of importance to recycling of waste lead storage batteries alloy. Copyright © 2018 Elsevier B.V. All rights reserved.

Ground water contamination by crude oil near Bemidji, Minnesota

USGS Publications Warehouse

Delin, G.N.; Essaid, H.I.; Cozzarelli, I.M.; Lahvis, M.H.; Bekins, B.A.

1998-01-01

Ground-water contamination by crude oil, and other petroleum-based liquids, is a widespread problem. An average of 83 crude-oil spills occurred per year during 1994-96 in the United States, each spilling about 50,000 barrels of crude oil (U.S. Office of Pipeline Safety, electronic commun., 1997). An understanding of the fate of organic contaminants (such as oil and gasoline) in the subsurface is needed to design innovative and cost-effective remedial solutions at contaminated sites.

Multipurpose Vacuum Induction Processing System

NASA Astrophysics Data System (ADS)

Govindaraju, M.; Kulkarni, Deepak; Balasubramanian, K.

2012-11-01

Multipurpose vacuum processing systems are cost effective; occupy less space, multiple functional under one roof and user friendly. A multipurpose vacuum induction system was designed, fabricated and installed in a record time of 6 months time at NFTDC Hyderabad. It was designed to function as a) vacuum induction melting/refining of oxygen free electronic copper/pure metals, b) vacuum induction melting furnace for ferrous materials c) vacuum induction melting for non ferrous materials d) large vacuum heat treatment chamber by resistance heating (by detachable coil and hot zone) e) bottom discharge vacuum induction melting system for non ferrous materials f) Induction heat treatment system and g) directional solidification /investment casting. It contains provision for future capacity addition. The attachments require to manufacture multiple shaped castings and continuous rod casting can be added whenever need arises. Present capacity is decided on the requirement for 10years of development path; presently it has 1.2 ton liquid copper handling capacity. It is equipped with provision for capacity addition up to 2 ton liquid copper handling capacity in future. Provision is made to carry out the capacity addition in easy steps quickly. For easy operational maintenance and troubleshooting, design was made in easily detachable sections. High vacuum system is also is detachable, independent and easily movable which is first of its kind in the country. Detailed design parameters, advantages and development history are presented in this paper.

3. EAGLE MILL, DETAIL OF CRUDE ORE BIN FROM NORTH, ...

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

3. EAGLE MILL, DETAIL OF CRUDE ORE BIN FROM NORTH, c. 1908-10. SHOWS EXPOSED CRUSHER HOUSE IN FRONT OF (SOUTH) CRUDE ORE BIN AND SNOW SHED ADDED OVER TRAM TRACKS. NOTE LACK OF EAST OR WEST CRUDE ORE BINS. CREDIT JW. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Inhibition of Acetoclastic Methanogenesis in Crude Oil- and Creosote-Contaminated Groundwater

USGS Publications Warehouse

Warren, E.; Bekins, B.A.; Godsy, E.M.; Smith, V.K.

2003-01-01

The inhibition of acetoclastic methanogenesis in crude oil- and creosote-contaminated groundwater was studied. The crude oil and water-soluble components of creosote contributed to the inhibition of acetoclastic methanogens. Acetoclastic methanogenesis was much more susceptible to the toxic inhibition of crude oil and creosote than either hydrogen- or formate-utilizing methanogenesis. The effect of this toxic inhibition was apparent in the population of the methanogenic trophic groups near nonaqueous crude oil at the Bemidji, MN, site. At a crude oil-contaminated site, numbers of acetoclastic methanogens found close to crude oil were 100 times fewer than those of hydrogen- and formate-utilizing methanogens. In laboratory toxicity assays, crude oil collected from the site inhibited methane production from acetate but not from formate or hydrogen. Toxicity assays with aqueous creosote extract completely inhibited acetate utilization over the range of tested dilutions but only mildly affected formate and hydrogen utilization. Wastewater reactor studies indicated that this toxicity would result in a decrease in the biodegradation rate of contaminants at sites where toxic compounds are present.

Evaluation and decontamination of crude oil-polluted soils using Centrosema pubescen Benth and amendment-support options.

PubMed

Nwaichi, Eucharia O; Osuji, Leo C; Onyeike, Eugene N

2011-04-01

Growth performance and phytoremediation of soil of the Niger Delta Region of Nigeria artificially-contaminated with crude oil (up to 100 mL/2 kg soil) using centrosema pubescen Benth was investigated for 12 weeks. The soil samples in which the plants were established were either un-amended, or amended with NPK, or UREA or chicken manure. The extents of removal of PAHs and BTEX were measured as well as the rates of growth of the plants. Gas Chromatographic analysis confirmed the degradation of carcinogenic hydrocarbons like BTEXs and PAHs with this technique. At the highest dose of crude, the contaminant concentrations were 43 mg/kg PAHs, 10 mg/kg BTEX, and 5,613 mg/kg O&G. The greatest percent removal of BTEX was observed at the highest contaminant dose, and with the manure amendment. Similar trends were observed with PAHs and although they were less marked, the trends with PAHs may have been more highly statistically significant. There was no measurable plant uptake of contaminants. Inhibition of plant growth (measured as leaf area, shoot length and production of dry weight) was proportional to the dose of crude oil, but the manure amendment was very effective at reducing the growth inhibition. Interestingly, manure amendment reduced the phytotoxicity significantly in this study.

Robot design for a vacuum environment

NASA Technical Reports Server (NTRS)

Belinski, S.; Trento, W.; Imani-Shikhabadi, R.; Hackwood, S.

1987-01-01

The cleanliness requirements for many processing and manufacturing tasks are becoming ever stricter, resulting in a greater interest in the vacuum environment. Researchers discuss the importance of this special environment, and the development of robots which are physically and functionally suited to vacuum processing tasks. Work is in progress at the Center for robotic Systems in Microelectronics (CRSM) to provide a robot for the manufacture of a revolutionary new gyroscope in high vacuum. The need for vacuum in this and other processes is discussed as well as the requirements for a vacuum-compatible robot. Finally, researchers present details on work done at the CRSM to modify an existing clean-room compatible robot for use at high vacuum.

Applications of crude incidence curves.

PubMed

Korn, E L; Dorey, F J

1992-04-01

Crude incidence curves display the cumulative number of failures of interest as a function of time. With competing causes of failure, they are distinct from cause-specific incidence curves that treat secondary types of failures as censored observations. After briefly reviewing their definition and estimation, we present five applications of crude incidence curves to show their utility in a broad range of studies. In some of these applications it is helpful to model survival-time distributions with use of two different time metameters, for example, time from diagnosis and age of the patient. We describe how one can incorporate published vital statistics into the models when secondary types of failure correspond to common causes of death.

Effects of Subsurface Microbial Ecology on Geochemical Evolution of a Crude-Oil Contaminated Aquifer

NASA Astrophysics Data System (ADS)

Bekins, B. A.; Cozzarelli, I. M.; Godsy, E. M.; Warren, E.; Hostettler, F. D.

2001-12-01

We have identified several subsurface habitats for microorganisms in a crude oil contaminated located near Bemidji, Minnesota. These aquifer habitats include: 1) the unsaturated zone contaminated by hydrocarbon vapors, 2) the zones containing separate-phase crude oil, and 3) the aqueous-phase contaminant plume. The surficial glacial outwash aquifer was contaminated when a crude oil pipeline burst in 1979. We analyzed sediment samples from the contaminated aquifer for the most probable numbers of aerobes, iron reducers, fermenters, and three types of methanogens. The microbial data were then related to gas, water, and oil chemistry, sediment extractable iron, and permeability. The microbial populations in the various contaminated subsurface habitats each have special characteristics and these affect the aquifer and contaminant chemistry. In the eight-meter-thick, vapor-contaminated vadose zone, a substantial aerobic population has developed that is supported by hydrocarbon vapors and methane. Microbial numbers peak in locations where access to both hydrocarbons and nutrients infiltrating from the surface is maximized. The activity of this population prevents hydrocarbon vapors from reaching the land surface. In the zone where separate-phase crude oil is present, a consortium of methanogens and fermenters dominates the populations both above and below the water table. Moreover, gas concentration data indicate that methane production has been active in the oily zone since at least 1986. Analyses of the extracted separate-phase oil show that substantial degradation of C15 -C35 n-alkanes has occurred since 1983, raising the possibility that significant degradation of C15 and higher n-alkanes has occurred under methanogenic conditions. However, lab and field data suggest that toxic inhibition by crude oil results in fewer acetate-utilizing methanogens within and adjacent to the separate-phase oil. Data from this and other sites indicate that toxic inhibition of

Distillation fraction-specific ecotoxicological evaluation of a paraffin-rich crude oil.

PubMed

Erlacher, Elisabeth; Loibner, Andreas P; Kendler, Romana; Scherr, Kerstin E

2013-03-01

Crude oil is a complex mixture of petroleum hydrocarbons (PHC) with distinct chemical, physical and toxicological properties relevant for contaminated site risk assessment. Ecotoxicological effects of crude oil distillation fractions on luminescent bacteria (Vibrio fischeri), earthworms (Dendrobaena hortensis) and invertebrates (Heterocypris incongruens) were tested using two spiked soils and their elutriates. Fraction 2 (F2) had an equivalent carbon number (ECN) range of >10 to 16, and F3 from >16 to 39. F2 showed a substantially higher ecotoxicological effect than F3 for Vibrio and Dendrobaena. In contrast, severe inhibition of Heterocypris by the poorly soluble F3 is attributed to mechanical organ blockage. Immediate sequestration of PHC to the organic matter-rich soil effected reduced toxicity for all organisms. This study indicates that a more differentiated consideration (i) of PHC mixtures based on ECN range and (ii) of model soil properties employed for ecotoxicity testing should be included into PHC-contaminated site risk assessment. Copyright © 2012 Elsevier Ltd. All rights reserved.

Classification of crude oils produced by in situ combustion

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

Ryabov, V.D.; Dauda, S.; Tabasaranskaya, T.Z.

1995-05-01

It was shown in that oil from the Karazhanbas field undergoes thermal and thermooxidative conversions in the course of production by in situ combustion (ISC). It has been proposed that crudes produced by this method should be assigned to three classes - those that have been subjected to thermal action only, those that have been subjected to thermooxidative action, and unconverted (native) crudes. This sort of classification is necessary in resolving questions of logical mixing of crudes, transportation, storage, and subsequent processing.

Safety studies on vacuum insulated liquid helium cryostats

NASA Astrophysics Data System (ADS)

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

2017-12-01

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

Induction of reactive oxygen species in marine phytoplankton under crude oil exposure.

PubMed

Ozhan, Koray; Zahraeifard, Sara; Smith, Aaron P; Bargu, Sibel

2015-12-01

Exposure of phytoplankton to the water-accommodated fraction of crude oil can elicit a number of stress responses, but the mechanisms that drive these responses are unclear. South Louisiana crude oil was selected to investigate its effects on population growth, chlorophyll a (Chl a) content, antioxidative defense, and lipid peroxidation, for the marine diatom, Ditylum brightwellii, and the dinoflagellate, Heterocapsa triquetra, in laboratory-based microcosm experiments. The transcript levels of several possible stress-responsive genes in D. brightwellii were also measured. The microalgae were exposed to crude oil for up to 96 h, and Chl a content, superoxide dismutase (SOD), the glutathione pool (GSH and GSSG), and lipid peroxidation content were analyzed. The cell growth of both phytoplankton species was inhibited with increasing crude oil concentrations. Crude oil exposure did not affect Chl a content significantly in cells. SOD activities showed similar responses in both species, being enhanced at 4- and 8-mg/L crude oil exposure. Only H. triquetra demonstrated enhanced activity in GSSG pool and lipid peroxidation at 8-mg/L crude oil exposure, suggesting that phytoplankton species have distinct physiological responses and tolerance levels to crude oil exposure. This study indicated the activation of reactive oxygen species (ROS) in phytoplankton under crude oil exposure; however, the progressive damage in cells is still unknown. Thus, ROS-related damage in nucleic acid, lipids, proteins, and DNA, due to crude oil exposure could be a worthwhile subject of study to better understand crude oil toxicity at the base of the food web.

Technical specification for vacuum systems

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

Khaw, J.

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

Bakeout Chamber Within Vacuum Chamber

NASA Technical Reports Server (NTRS)

Taylor, Daniel M.; Soules, David M.; Barengoltz, Jack B.

1995-01-01

Vacuum-bakeout apparatus for decontaminating and measuring outgassing from pieces of equipment constructed by mounting bakeout chamber within conventional vacuum chamber. Upgrade cost effective: fabrication and installation of bakeout chamber simple, installation performed quickly and without major changes in older vacuum chamber, and provides quantitative data on outgassing from pieces of equipment placed in bakeout chamber.

10 CFR 212.78 - Tertiary incentive crude oil.

Code of Federal Regulations, 2010 CFR

2010-01-01

... operator with respect to any enhanced oil recovery project for which a report had been filed previously... 10 Energy 3 2010-01-01 2010-01-01 false Tertiary incentive crude oil. 212.78 Section 212.78 Energy DEPARTMENT OF ENERGY OIL MANDATORY PETROLEUM PRICE REGULATIONS Producers of Crude Oil § 212.78 Tertiary...

Potential uses of vacuum bubbles in noise and vibration control

NASA Technical Reports Server (NTRS)

Ver, Istvan L.

1989-01-01

Vacuum bubbles are new acoustic elements which are dynamically more compliant than the gas volume they replace, but which are statically robust. They are made of a thin metallic shell with vacuum in their cavity. Consequently, they pose no danger in terms of contamination or fire hazard. The potential of the vacuum bubble concept for noise and vibration control was assessed with special emphases on spacecraft and aircraft applications. The following potential uses were identified: (1) as a cladding, to reduce sound radiation of vibrating surfaces and the sound excitation of structures, (2) as a screen, to reflect or absorb an incident sound wave, and (3) as a liner, to increase low frequency sound transmission loss of double walls and to increase the low frequency sound attenuation of muffler baffles. It was found that geometric and material parameters must be controlled to a very high accuracy to obtain optimal performance and that performance is highly sensitive to variations in static pressure. Consequently, it was concluded that vacuum bubbles have more potential in spacecraft applications where static pressure is controlled more than in aircraft applications where large fluctuations in static pressure are common.

Development and Testing of an ISRU Soil Mechanics Vacuum Test Facility

NASA Technical Reports Server (NTRS)

Kleinhenz, Julie E.; Wilkinson, R. Allen

2014-01-01

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

Leadership Strategies for Maintaining Profitability in a Volatile Crude Oil Market

NASA Astrophysics Data System (ADS)

Braimoh, Lucky Anderson

Volatile crude oil prices significantly affect the profitability of crude oil firms. The purpose of this single case study was to explore strategies some crude oil and gas business leaders used to remain profitable during periods of crude oil price volatility. The target population comprised 8 crude oil and gas business leaders located in Calgary, Canada, whose company remained profitable despite crude oil price volatility. The transformational leadership theory formed the conceptual framework for the study. Data were collected through the use of semistructured face-to-face interviews, company reports, and field notes. Data analysis involved a modified Van Kamm method, which included descriptive coding, a sequential review of the interview transcripts, and member checking. Based on methodological triangulation and thematic analysis, 5 themes emerged from the study, including communication and engagement; motivation and empowerment; measurement, monitoring, and control; self-awareness and humility; and efficiency and optimization. The implications for social change include the potential for crude oil and gas companies in Calgary, Canada to manage production costs, ensure earnings and profitability, and thus improve the socioeconomic well-being of Calgary indigenes through improved employment opportunities.

Prediction of physical-chemical properties of crude oils by 1H NMR analysis of neat samples and chemometrics.

PubMed

Masili, Alice; Puligheddu, Sonia; Sassu, Lorenzo; Scano, Paola; Lai, Adolfo

2012-11-01

In this work, we report the feasibility study to predict the properties of neat crude oil samples from 300-MHz NMR spectral data and partial least squares (PLS) regression models. The study was carried out on 64 crude oil samples obtained from 28 different extraction fields and aims at developing a rapid and reliable method for characterizing the crude oil in a fast and cost-effective way. The main properties generally employed for evaluating crudes' quality and behavior during refining were measured and used for calibration and testing of the PLS models. Among these, the UOP characterization factor K (K(UOP)) used to classify crude oils in terms of composition, density (D), total acidity number (TAN), sulfur content (S), and true boiling point (TBP) distillation yields were investigated. Test set validation with an independent set of data was used to evaluate model performance on the basis of standard error of prediction (SEP) statistics. Model performances are particularly good for K(UOP) factor, TAN, and TPB distillation yields, whose standard error of calibration and SEP values match the analytical method precision, while the results obtained for D and S are less accurate but still useful for predictions. Furthermore, a strategy that reduces spectral data preprocessing and sample preparation procedures has been adopted. The models developed with such an ample crude oil set demonstrate that this methodology can be applied with success to modern refining process requirements. Copyright © 2012 John Wiley & Sons, Ltd.

Vacuum MOCVD fabrication of high efficience cells

NASA Technical Reports Server (NTRS)

Partain, L. D.; Fraas, L. M.; Mcleod, P. S.; Cape, J. A.

1985-01-01

Vacuum metal-organic-chemical-vapor-deposition (MOCVD) is a new fabrication process with improved safety and easier scalability due to its metal rather than glass construction and its uniform multiport gas injection system. It uses source materials more efficiently than other methods because the vacuum molecular flow conditions allow the high sticking coefficient reactants to reach the substrates as undeflected molecular beams and the hot chamber walls cause the low sticking coefficient reactants to bounce off the walls and interact with the substrates many times. This high source utilization reduces the materials costs power device and substantially decreases the amounts of toxic materials that must be handled as process effluents. The molecular beams allow precise growth control. With improved source purifications, vacuum MOCVD has provided p GaAs layers with 10-micron minority carrier diffusion lengths and GaAs and GaAsSb solar cells with 20% AMO efficiencies at 59X and 99X sunlight concentration ratios. Mechanical stacking has been identified as the quickest, most direct and logical path to stacked multiple-junction solar cells that perform better than the best single-junction devices. The mechanical stack is configured for immediate use in solar arrays and allows interconnections that improve the system end-of-life performance in space.

Comparison of occlusion break responses and vacuum rise times of phacoemulsification systems.

PubMed

Sharif-Kashani, Pooria; Fanney, Douglas; Injev, Val

2014-07-30

Occlusion break surge during phacoemulsification cataract surgery can lead to potential surgical complications. The purpose of this study was to quantify occlusion break surge and vacuum rise time of current phacoemulsification systems used in cataract surgery. Occlusion break surge at vacuum pressures between 200 and 600 mmHg was assessed with the Infiniti® Vision System, the WhiteStar Signature® Phacoemulsification System, and the Centurion® Vision System using gravity-fed fluidics. Centurion Active FluidicsTM were also tested at multiple intraoperative pressure target settings. Vacuum rise time was evaluated for Infiniti, WhiteStar Signature, Centurion, and Stellaris® Vision Enhancement systems. Rise time to vacuum limits of 400 and 600 mmHg was assessed at flow rates of 30 and 60 cc/minute. Occlusion break surge was analyzed by 2-way analysis of variance. The Centurion system exhibited substantially less occlusion break surge than the other systems tested. Surge area with Centurion Active Fluidics was similar to gravity fluidics at an equivalent bottle height. At all Centurion Active Fluidics intraoperative pressure target settings tested, surge was smaller than with Infiniti and WhiteStar Signature. Infiniti had the fastest vacuum rise time and Stellaris had the slowest. No system tested reached the 600-mmHg vacuum limit. In this laboratory study, Centurion had the least occlusion break surge and similar vacuum rise times compared with the other systems tested. Reducing occlusion break surge may increase safety of phacoemulsification cataract surgery.

Steam ejector-condenser: stage I of a differential vacuum pumping station

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

Hanson, C.L.; Alger, T.W.

1981-04-01

A steam ejector-condenser unit was built and tested to produce a 10 Torr (13.3 x 10/sup 2/Pa) vacuum with a 2 cm aperture to the atmosphere. This unit is the first stage of a differential vacuum pumping station that will be used with the Experimental Test Accelerator. The accelerator's electron beam will pass through a series of openings from a high vacuum (5 x 10/sup -6/ Torr) to the atmosphere. The differential system consists of four vacuum pumping units separated by 2 cm-diam apertures. Superheated steam is injected near the final beamline orifice to reduce the quantity of atmospheric airmore » flowing into the steam ejector--condenser unit. The steam ejector in the condenser vessel is open at its center to permit passage of the accelerator beam. Five nozzles mounted in a conical array produce the ejector vacuum of 10 Torr. The ejector exhausts into the condenser and forms a barrier to air flow into the lower pressure region. This feature permits high volume cold trapping and cryopumping of water vapor in the remaining lower-pressure stages. Tests have proven that the steam ejector--condenser is a reliable operating unit and suitable for long-term, steady-state accelerator operation.« less

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

NASA Astrophysics Data System (ADS)

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

2014-11-01

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

Achieving ultrahigh vacuum in an unbaked chamber with glow discharge conditioning

NASA Astrophysics Data System (ADS)

Khan, Ziauddin; Semwal, Pratibha; Dhanani, Kalpesh R.; Raval, Dilip C.; Pradhan, Subrata

2017-01-01

Glow discharge conditioning (GDC) has long been accepted as one of the basic wall conditioning techniques for achieving ultrahigh vacuum in an unbaked chamber. As a part of this fundamental experimental study, a test chamber has been fabricated from stainless steel 304 L with its inner surface electropolished on which a detailed investigation has been carried out. Both helium and hydrogen gases have been employed as discharge cleaning medium. The discharge cleaning was carried out at 0.1 A / m 2 current density with working pressure maintained at 1.0 × 10 -2 mbar. It was experimentally observed that the pump-down time to attain the base pressure 10 -8 mbar was reduced by 62% compared to the unbaked chamber being pumped to this ultimate vacuum. The results were similar irrespective of whether the discharge cleaning medium is either hydrogen or helium. It was also experimentally established that a better ultimate vacuum could be achieved as compared to theoretically calculated ultimate vacuum with the help of discharge cleaning.

Catalytic hydrothermal upgrading of crude bio-oils produced from different thermo-chemical conversion routes of microalgae.

PubMed

Duan, Peigao; Wang, Bing; Xu, Yuping

2015-06-01

This study presents experimental results that compare the use of hydrothermal liquefaction (HTL), alcoholysis (Al), pyrolysis (Py) and hydropyrolysis (HPy) for the production of bio-oil from a microalga (Chlorella pyrenoidosa) and the catalytic hydrothermal upgrading of crude bio-oils produced by these four conversion routes. The yields and compositions of bio-oil, solid residue, and gases were evaluated and compared. HTL resulted in a bio-oil that has a higher energy density and superior fuel properties, such as thermal and storage stabilities, compared with the other three conversion routes. The N in crude bio-oils produced from Py and HPy is more easily removed than that in the bio-oils produced from HTL and Al. The upgraded bio-oils contain reduced amounts of certain O-containing and N-containing compounds and significantly increased saturated hydrocarbon contents. All of the upgraded bio-oils have a larger fraction boiling below 350°C than their corresponding crude bio-oils. Copyright © 2015 Elsevier Ltd. All rights reserved.

Improving Vacuum Cleaners

NASA Technical Reports Server (NTRS)

1997-01-01

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

Crude glycerin for monogastrics

USDA-ARS?s Scientific Manuscript database

With the rapid expansion of the biodiesel industry there will be substantial amounts of crude glycerol (the principal co-product of biodiesel production) that will become available for use as a livestock feedstuff. Because glycerol is a precursor to glucose via gluconeogenesis, is a backbone of fat ...

Adjuvant treatment with crude rhubarb for patients with acute organophosphorus pesticide poisoning: A meta-analysis of randomized controlled trials.

PubMed

Wang, Lina; Pan, Shuming

2015-12-01

Crude rhubarb has been used to treat critically ill patients for many years. However, no previous meta-analysis has been investigated the benefits of crude rhubarb in patients with acute organophosphorus pesticide poisoning (AOPP). To summarize the beneficial effects of adjuvant treatment with crude rhubarb in patients with AOPP by conducting a meta-analysis. A literature search of the databases through Pubmed, EMBASE, China National Knowledge Infrastructure, VIP, and Wanfang were performed for studies published up to October 2014. Randomized controlled trials (RCTs) investigating the effects of crude rhubarb as adjuvant treatment for patients with AOPP were included. A total of 12 RCTs with 886 patients were identified. Adjuvant treatment with crude rhubarb was associated with a significantly lower incidence of intermediate syndrome (risk ratio [RR] 0.22; 95% confidence interval [CI] 0.10-0.48), as well as multiple organ dysfunction syndrome (RR 0.34; 95% CI 0.20-0.56). Crude rhubarb as adjuvant treatment reduced the total dose of pralidoxime (mean difference [MD] -5.12 g; 95% CI -8.24 to -2.00) or atropine (MD -94.89 mg; 95% CI -156.22 to -33.57), and hospital length of stay (MD -2.79 days; 95% CI -4.19 to -1.39) compared with the controls. This meta-analysis suggests that crude rhubarb as adjuvant treatment appears to have additional beneficial effects in patients with AOPP. More well-designed trials are needed to confirm our findings due to the methodological flaws of the included trials. Copyright © 2015 Elsevier Ltd. All rights reserved.

Low-Cost, Rugged High-Vacuum System

NASA Technical Reports Server (NTRS)

Sorensen, Paul; Kline-Schoder, Robert

2012-01-01

A need exists for miniaturized, rugged, low-cost high-vacuum systems. Recent advances in sensor technology have led to the development of very small mass spectrometer detectors as well as other analytical instruments such as scanning electron microscopes. However, the vacuum systems to support these sensors remain large, heavy, and power-hungry. To meet this need, a miniaturized vacuum system was developed based on a very small, rugged, and inexpensive-to-manufacture molecular drag pump (MDP). The MDP is enabled by a miniature, very-high-speed (200,000 rpm), rugged, low-power, brushless DC motor optimized for wide temperature operation and long life. The key advantages of the pump are reduced cost and improved ruggedness compared to other mechanical hig-hvacuum pumps. The machining of the rotor and stators is very simple compared to that necessary to fabricate rotor and stator blades for other pump designs. Also, the symmetry of the rotor is such that dynamic balancing of the rotor will likely not be necessary. Finally, the number of parts in the unit is cut by nearly a factor of three over competing designs. The new pump forms the heart of a complete vacuum system optimized to support analytical instruments in terrestrial applications and on spacecraft and planetary landers. The MDP achieves high vacuum coupled to a ruggedized diaphragm rough pump. Instead of the relatively complicated rotor and stator blades used in turbomolecular pumps, the rotor in the MDP consists of a simple, smooth cylinder of aluminum. This will turn at approximately 200,000 rpm inside an outer stator housing. The pump stator comprises a cylindrical aluminum housing with one or more specially designed grooves that serve as flow channels. To minimize the length of the pump, the gas is forced down the flow channels of the outer stator to the base of the pump. The gas is then turned and pulled toward the top through a second set of channels cut into an inner stator housing that surrounds the

Weak stability of the plasma-vacuum interface problem

NASA Astrophysics Data System (ADS)

Catania, Davide; D'Abbicco, Marcello; Secchi, Paolo

2016-09-01

We consider the free boundary problem for the two-dimensional plasma-vacuum interface in ideal compressible magnetohydrodynamics (MHD). In the plasma region, the flow is governed by the usual compressible MHD equations, while in the vacuum region we consider the Maxwell system for the electric and the magnetic fields. At the free interface, driven by the plasma velocity, the total pressure is continuous and the magnetic field on both sides is tangent to the boundary. We study the linear stability of rectilinear plasma-vacuum interfaces by computing the Kreiss-Lopatinskiĭ determinant of an associated linearized boundary value problem. Apart from possible resonances, we obtain that the piecewise constant plasma-vacuum interfaces are always weakly linearly stable, independently of the size of tangential velocity, magnetic and electric fields on both sides of the characteristic discontinuity. We also prove that solutions to the linearized problem obey an energy estimate with a loss of regularity with respect to the source terms, both in the interior domain and on the boundary, due to the failure of the uniform Kreiss-Lopatinskiĭ condition, as the Kreiss-Lopatinskiĭ determinant associated with this linearized boundary value problem has roots on the boundary of the frequency space. In the proof of the a priori estimates, a crucial part is played by the construction of symmetrizers for a reduced differential system, which has poles at which the Kreiss-Lopatinskiĭ condition may fail simultaneously.

Feasibility Process for Remediation of the Crude Oil Contaminated Soil

NASA Astrophysics Data System (ADS)

Keum, H.; Choi, H.; Heo, H.; Lee, S.; Kang, G.

2015-12-01

More than 600 oil wells were destroyed in Kuwait by Iraqi in 1991. During the war, over 300 oil lakes with depth of up to 2m at more than 500 different locations which has been over 49km2. Therefore, approximately 22 million m3was crude oil contaminated. As exposure of more than 20 years under atmospheric conditions of Kuwait, the crude oil has volatile hydrocarbons and covered heavy oily sludge under the crude oil lake. One of crude oil contaminated soil which located Burgan Oilfield area was collected by Kuwait Oil Company and got by H-plus Company. This contaminated soil has about 42% crude oil and could not biodegraded itself due to the extremely high toxicity. This contaminated soil was separated by 2mm sieve for removal oil sludge ball. Total petroleum hydrocarbons (TPH) was analysis by GC FID and initial TPH concentration was average 48,783 mg/kg. Ten grams of the contaminated soil replaced in two micro reactors with 20mL of bio surfactant produce microorganism. Reactor 1 was added 0.1g powder hemoglobin and other reactor was not added hemoglobin at time 0 day. Those reactors shake 120 rpm on the shaker for 7 days and CO2 produced about 150mg/L per day. After 7 days under the slurry systems, the rest days operated by hemoglobin as primary carbon source for enhanced biodegradation. The crude oil contaminated soil was degraded from 48,783mg/kg to 20,234mg/kg by slurry process and final TPH concentration degraded 11,324mg/kg for 21days. Therefore, highly contaminated soil by crude oil will be combined bio slurry process and biodegradation process with hemoglobin as bio catalytic source. Keywords: crude-oil contaminated soil, bio slurry, biodegradation, hemoglobin ACKOWLEDGEMENTS This project was supported by the Korea Ministry of Environment (MOE) GAIA Program

Technical Proposal for Loading 3000 Gallon Crude Oil Samples from Field Terminal to Sandia Pressurized Tanker to Support US DOE/DOT Crude Oil Characterization Research Study

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

Lord, David L.; Allen, Raymond

Sandia National Laboratories is seeking access to crude oil samples for a research project evaluating crude oil combustion properties in large-scale tests at Sandia National Laboratories in Albuquerque, NM. Samples must be collected from a source location and transported to Albuquerque in a tanker that complies with all applicable regulations for transportation of crude oil over public roadways. Moreover, the samples must not gain or lose any components, to include dissolved gases, from the point of loading through the time of combustion at the Sandia testing facility. In order to achieve this, Sandia designed and is currently procuring a custommore » tanker that utilizes water displacement in order to achieve these performance requirements. The water displacement procedure is modeled after the GPA 2174 standard “Obtaining Liquid Hydrocarbons Samples for Analysis by Gas Chromatography” (GPA 2014) that is used routinely by crude oil analytical laboratories for capturing and testing condensates and “live” crude oils, though it is practiced at the liter scale in most applications. The Sandia testing requires 3,000 gallons of crude. As such, the water displacement method will be upscaled and implemented in a custom tanker. This report describes the loading process for acquiring a ~3,000 gallon crude oil sample from commercial process piping containing single phase liquid crude oil at nominally 50-100 psig. This document contains a general description of the process (Section 2), detailed loading procedure (Section 3) and associated oil testing protocols (Section 4).« less

Dispersion Of Crude Oil And Petroleum Products In Freshwater

EPA Science Inventory

The objective of this research was to investigate the relationship between dispersion effectiveness in freshwater and the surfactant composition for fresh and weathered crude oil. Although limited research on the chemical dispersion of crude oil and petroleum products in freshwat...

Chronic crude garlic-feeding modified adult male rat testicular markers: mechanisms of action

PubMed Central

Hammami, Imen; Amara, Souheila; Benahmed, Mohamed; El May, Michèle V; Mauduit, Claire

2009-01-01

Background Garlic or Allium sativum (As) shows therapeutic effects such as reduction of blood pressure or hypercholesterolemia but side-effects on reproductive functions remain poorly investigated. Because of garlic's chemical complexity, the processing methods and yield in preparations differ in efficacy and safety. In this context, we clarify the mechanisms of action of crushed crude garlic on testicular markers. Methods During one month of treatment, 24 male rats were fed 5%, 10% and 15% crude garlic. Results We showed that crude garlic-feeding induced apoptosis in testicular germ cells (spermatocytes and spermatids). This cell death process was characterized by increased levels of active CASP3 but not CASP6. Expression of the caspase inhibitors BIRC3 and BIRC2 was increased at all doses of As while expression of XIAP and BIRC5 was unchanged. Moreover, expression of the IAP inhibitor DIABLO was increased at doses 10% and 15% of As. The germ cell death process induced by As might be related to a decrease in testosterone production because of the reduced expression of steroidogenic enzymes (Star, Cyp11a, Hsd3b5 and Hsd17b). Evaluation of Sertoli markers showed that TUBB3 and GSTA2 expression was unchanged. In contrast, AMH, RHOX5 and CDKN1B expression was decreased while GATA4 expression was increased. Conclusion In summary, we showed that feeding with crude garlic inhibited Leydig steroidogenic enzyme expression and Sertoli cell markers. These alterations might induce apoptosis in testicular germ cells. PMID:19552815

[Vacuum-assisted therapy for various wound types including diabetic foot ulcer].

PubMed

Farah, Raymond; Gantus, Maher; Kogan, Leonid

2011-03-01

Vacuum is a noninvasive system that creates a localized controlled negative pressure environment. In this study, vacuum was provided by the V.A.C. Therapy system, which promotes wound healing by delayed primary or secondary intention through creating a moist wound environment, preparing the wound bed for closure, reducing edema, and promoting formation and perfusion of granulation tissue. Vacuum-assisted closure therapy is indicated for use in all care settings and for a variety of wound types including diabetic foot ulcers. The purpose of this study was to evaluate safety and clinical efficacy of negative pressure wound therapy (NPWT) compared with advanced moist wound therapy and standard treatment to treat foot ulcers in diabetic patients. This trial enrolled 43 patients; most of them were diabetic patients at any age with various skin ulcers and diabetic foot. These patients were divided into two groups, 17 patients were treated with vacuum and the 26 patients in the control group were treated with standard therapy including debridement. A greater proportion of foot and skin ulcers achieved complete ulcer closure with vacuum-assisted therapy p<0.001 compared with the standard therapy. Vacuum therapy significantly decreased the duration and frequency of admission p=0.032 and decreased the rate of amputation p<0.001. Results of our trial support other studies and demonstrate that vacuum is as safe as and more efficacious than standard therapy in the treatment of diabetic foot ulcers. A significantly greater number of patients achieved complete ulcer closure and granulation tissue formation with this therapy. The study group showed a significant reduction in the median time needed to heal ulcers, reduction of the number of admissions and amputation frequency.

Sol-gel derived flexible silica aerogel as selective adsorbent for water decontamination from crude oil.

PubMed

Abolghasemi Mahani, A; Motahari, S; Mohebbi, A

2018-04-01

Oil spills are the most important threat to the sea ecosystem. The present study is an attempt to investigate the effects of sol-gel parameters on seawater decontamination from crude oil by use of flexible silica aerogel. To this goal, methyltrimethoxysilane (MTMS) based silica aerogels were prepared by two-step acid-base catalyzed sol-gel process, involving ambient pressure drying (APD) method. To investigate the effects of sol-gel parameters, the aerogels were prepared under two different acidic and basic pH values (i.e. 4 and 8) and varied ethanol/MTMS molar ratios from 5 to 15. The adsorption capacity of the prepared aerogels was evaluated for two heavy and light commercial crude oils under multiple adsorption-desorption cycles. To reduce process time, desorption cycles were carried out by using roll milling for the first time. At optimum condition, silica aerogels are able to uptake heavy and light crude oils with the order of 16.7 and 13.7, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Switching Circuit for Shop Vacuum System

NASA Technical Reports Server (NTRS)

Burley, R. K.

1987-01-01

No internal connections to machine tools required. Switching circuit controls vacuum system draws debris from grinders and sanders in machine shop. Circuit automatically turns on vacuum system whenever at least one sander or grinder operating. Debris safely removed, even when operator neglects to turn on vacuum system manually. Pickup coils sense alternating magnetic fields just outside operating machines. Signal from any coil or combination of coils causes vacuum system to be turned on.

Corresponding morphological and molecular indicators of crude oil toxicity to the developing hearts of mahi mahi

NASA Astrophysics Data System (ADS)

Edmunds, Richard C.; Gill, J. A.; Baldwin, David H.; Linbo, Tiffany L.; French, Barbara L.; Brown, Tanya L.; Esbaugh, Andrew J.; Mager, Edward M.; Stieglitz, John; Hoenig, Ron; Benetti, Daniel; Grosell, Martin; Scholz, Nathaniel L.; Incardona, John P.

2015-12-01

Crude oils from distinct geological sources worldwide are toxic to developing fish hearts. When oil spills occur in fish spawning habitats, natural resource injury assessments often rely on conventional morphometric analyses of heart form and function. The extent to which visible indicators correspond to molecular markers for cardiovascular stress is unknown for pelagic predators from the Gulf of Mexico. Here we exposed mahi (Coryphaena hippurus) embryos to field-collected crude oil samples from the 2010 Deepwater Horizon disaster. We compared visible heart defects (edema, abnormal looping, reduced contractility) to changes in expression of cardiac-specific genes that are diagnostic of heart failure in humans or associated with loss-of-function zebrafish cardiac mutants. Mahi exposed to crude oil during embryogenesis displayed typical symptoms of cardiogenic syndrome as larvae. Contractility, looping, and circulatory defects were evident, but larval mahi did not exhibit downstream craniofacial and body axis abnormalities. A gradation of oil exposures yielded concentration-responsive changes in morphometric and molecular responses, with relative sensitivity being influenced by age. Our findings suggest that 1) morphometric analyses of cardiac function are more sensitive to proximal effects of crude oil-derived chemicals on the developing heart, and 2) molecular indicators reveal a longer-term adverse shift in cardiogenesis trajectory.

Corresponding morphological and molecular indicators of crude oil toxicity to the developing hearts of mahi mahi

PubMed Central

Edmunds, Richard C.; Gill, J. A.; Baldwin, David H.; Linbo, Tiffany L.; French, Barbara L.; Brown, Tanya L.; Esbaugh, Andrew J.; Mager, Edward M.; Stieglitz, John; Hoenig, Ron; Benetti, Daniel; Grosell, Martin; Scholz, Nathaniel L.; Incardona, John P.

2015-01-01

Crude oils from distinct geological sources worldwide are toxic to developing fish hearts. When oil spills occur in fish spawning habitats, natural resource injury assessments often rely on conventional morphometric analyses of heart form and function. The extent to which visible indicators correspond to molecular markers for cardiovascular stress is unknown for pelagic predators from the Gulf of Mexico. Here we exposed mahi (Coryphaena hippurus) embryos to field-collected crude oil samples from the 2010 Deepwater Horizon disaster. We compared visible heart defects (edema, abnormal looping, reduced contractility) to changes in expression of cardiac-specific genes that are diagnostic of heart failure in humans or associated with loss-of-function zebrafish cardiac mutants. Mahi exposed to crude oil during embryogenesis displayed typical symptoms of cardiogenic syndrome as larvae. Contractility, looping, and circulatory defects were evident, but larval mahi did not exhibit downstream craniofacial and body axis abnormalities. A gradation of oil exposures yielded concentration-responsive changes in morphometric and molecular responses, with relative sensitivity being influenced by age. Our findings suggest that 1) morphometric analyses of cardiac function are more sensitive to proximal effects of crude oil-derived chemicals on the developing heart, and 2) molecular indicators reveal a longer-term adverse shift in cardiogenesis trajectory. PMID:26658479

Vacuum Brazing of Accelerator Components

NASA Astrophysics Data System (ADS)

Singh, Rajvir; Pant, K. K.; Lal, Shankar; Yadav, D. P.; Garg, S. R.; Raghuvanshi, V. K.; Mundra, G.

2012-11-01

Commonly used materials for accelerator components are those which are vacuum compatible and thermally conductive. Stainless steel, aluminum and copper are common among them. Stainless steel is a poor heat conductor and not very common in use where good thermal conductivity is required. Aluminum and copper and their alloys meet the above requirements and are frequently used for the above purpose. The accelerator components made of aluminum and its alloys using welding process have become a common practice now a days. It is mandatory to use copper and its other grades in RF devices required for accelerators. Beam line and Front End components of the accelerators are fabricated from stainless steel and OFHC copper. Fabrication of components made of copper using welding process is very difficult and in most of the cases it is impossible. Fabrication and joining in such cases is possible using brazing process especially under vacuum and inert gas atmosphere. Several accelerator components have been vacuum brazed for Indus projects at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore using vacuum brazing facility available at RRCAT, Indore. This paper presents details regarding development of the above mentioned high value and strategic components/assemblies. It will include basics required for vacuum brazing, details of vacuum brazing facility, joint design, fixturing of the jobs, selection of filler alloys, optimization of brazing parameters so as to obtain high quality brazed joints, brief description of vacuum brazed accelerator components etc.

Crude glycerin in swine

USDA-ARS?s Scientific Manuscript database

With the rapid expansion of the bio-diesel industry, there will be substantial amounts of crude glycerol (the principal co-product of bio-diesel production) that will become available for use as a livestock feedstuff. Because glycerol is a precursor to glucose via gluconeogenesis, is a backbone of f...

Optimal Operation of a Josephson Parametric Amplifier for Vacuum Squeezing

NASA Astrophysics Data System (ADS)

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

2018-04-01

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

Preventing Clogging In A Vacuum Plasma Spray Gun

NASA Technical Reports Server (NTRS)

Krotz, Phillip D.; Daniel, Ronald L., Jr.; Davis, William M.

1994-01-01

Modification of powder-injection ports enables lengthy, high-temperature deposition operations. Graphite inserts prevent clogging of ports through which copper powder injected into vacuum plasma spray (VPS) gun. Graphite liners eliminate need to spend production time refurbishing VPS gun, reducing cost of production and increasing productivity. Concept also applied to other material systems used for net-shape fabrication via VPS.

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

NASA Astrophysics Data System (ADS)

Shioiri, Tetsu; Asari, Naoki; Sato, Junichi; Sasage, Kosuke; Yokokura, Kunio; Homma, Mitsutaka; Suzuki, Katsumi

To investigate the reliability of equipment of vacuum insulation, a study was carried out to clarify breakdown probability distributions in vacuum gap. Further, a double-break vacuum circuit breaker was investigated for breakdown probability distribution. The test results show that the breakdown probability distribution of the vacuum gap can be represented by a Weibull distribution using a location parameter, which shows the voltage that permits a zero breakdown probability. The location parameter obtained from Weibull plot depends on electrode area. The shape parameter obtained from Weibull plot of vacuum gap was 10∼14, and is constant irrespective non-uniform field factor. The breakdown probability distribution after no-load switching can be represented by Weibull distribution using a location parameter. The shape parameter after no-load switching was 6∼8.5, and is constant, irrespective of gap length. This indicates that the scatter of breakdown voltage was increased by no-load switching. If the vacuum circuit breaker uses a double break, breakdown probability at low voltage becomes lower than single-break probability. Although potential distribution is a concern in the double-break vacuum cuicuit breaker, its insulation reliability is better than that of the single-break vacuum interrupter even if the bias of the vacuum interrupter's sharing voltage is taken into account.

Switchable Adhesion in Vacuum Using Bio-Inspired Dry Adhesives.

PubMed

Purtov, Julia; Frensemeier, Mareike; Kroner, Elmar

2015-11-04

Suction based attachment systems for pick and place handling of fragile objects like glass plates or optical lenses are energy-consuming and noisy and fail at reduced air pressure, which is essential, e.g., in chemical and physical vapor deposition processes. Recently, an alternative approach toward reversible adhesion of sensitive objects based on bioinspired dry adhesive structures has emerged. There, the switching in adhesion is achieved by a reversible buckling of adhesive pillar structures. In this study, we demonstrate that these adhesives are capable of switching adhesion not only in ambient air conditions but also in vacuum. Our bioinspired patterned adhesive with an area of 1 cm(2) provided an adhesion force of 2.6 N ± 0.2 N in air, which was reduced to 1.9 N ± 0.2 N if measured in vacuum. Detachment was induced by buckling of the structures due to a high compressive preload and occurred, independent of air pressure, at approximately 0.9 N ± 0.1 N. The switch in adhesion was observed at a compressive preload between 5.6 and 6.0 N and was independent of air pressure. The difference between maximum adhesion force and adhesion force after buckling gives a reasonable window of operation for pick and place processes. High reversibility of the switching behavior is shown over 50 cycles in air and in vacuum, making the bioinspired switchable adhesive applicable for handling operations of fragile objects.

Switchable Adhesion in Vacuum Using Bio-Inspired Dry Adhesives

PubMed Central

2015-01-01

Suction based attachment systems for pick and place handling of fragile objects like glass plates or optical lenses are energy-consuming and noisy and fail at reduced air pressure, which is essential, e.g., in chemical and physical vapor deposition processes. Recently, an alternative approach toward reversible adhesion of sensitive objects based on bioinspired dry adhesive structures has emerged. There, the switching in adhesion is achieved by a reversible buckling of adhesive pillar structures. In this study, we demonstrate that these adhesives are capable of switching adhesion not only in ambient air conditions but also in vacuum. Our bioinspired patterned adhesive with an area of 1 cm2 provided an adhesion force of 2.6 N ± 0.2 N in air, which was reduced to 1.9 N ± 0.2 N if measured in vacuum. Detachment was induced by buckling of the structures due to a high compressive preload and occurred, independent of air pressure, at approximately 0.9 N ± 0.1 N. The switch in adhesion was observed at a compressive preload between 5.6 and 6.0 N and was independent of air pressure. The difference between maximum adhesion force and adhesion force after buckling gives a reasonable window of operation for pick and place processes. High reversibility of the switching behavior is shown over 50 cycles in air and in vacuum, making the bioinspired switchable adhesive applicable for handling operations of fragile objects. PMID:26457864

Ultrasound Assisted Synthesis of Hydroxylated Soybean Lecithin from Crude Soybean Lecithin as an Emulsifier.

PubMed

Chiplunkar, Pranali P; Pratap, Amit P

2017-10-01

Soybean lecithin is a by-product obtained during degumming step of crude soybean oil refining. Crude soybean lecithin (CSL) contains major amount of phospholipids (PLs) along with minor amount of acylglycerols, bioactive components, etc. Due to presence of PLs, CSL can be used as an emulsifier. Crude soybean lecithin (CSL) was utilized to synthesize hydroxylated soybean lecithin (HSL) by hydroxylation using hydrogen peroxide and catalytic amount of lactic acid to enhance the hydrophilicity and emulsifying properties of CSL. To reduce the reaction time and to increase rate of reaction, HSL was synthesized under ultrasound irradiation. The effect of different operating parameters such as lactic acid, hydrogen peroxide, temperature, ultrasonic power and duty cycle in synthesis of HSL were studied and optimized. The surface tension (SFT), interfacial tension (IFT) and the critical micelle concentration (CMC) of the HSL (26.11 mN/m, 2.67 mN/m, 112 mg/L) were compared to CSL (37.53 mN/m, 6.22 mN/m, 291 mg/L) respectively. The HSL has better emulsion stability and low foaming characteristics as compared to CSL. Therefore, the product as an effective emulsifier can be used in food, pharmacy, lubricant, cosmetics, etc.

Antiulcerogenic activity of crude extract, fractions and populnoic acid isolated from Austroplenckia populnea (Celastraceae).

PubMed

Andrade, Sérgio F; Antoniolli, Daiane; Comunello, Eros; Cardoso, Luis G V; Carvalho, José C T; Bastos, Jairo K

2006-01-01

Many plant crude extracts and their isolated compounds are the most attractive sources of new drugs and show promising results for the treatment of gastric ulcers. Austroplenckia populnea is commonly known as "marmelinho-do campo, mangabeira-brava, mangabarana and vime" and it has been used in folk medicine as anti-dysenteric and anti-rheumatic. Powdered bark wood (3.25 kg) was macerated with aqueous ethanol (96%) and the extract was concentrated under reduced pressure to yield 406 g of crude hydralcoholic extract. The hydralcoholic extract was suspended in aqueous methanol and partitioned with hexane, chloroform and ethyl acetate (EtOAc) in sequence, yielding 8.0 g, 9.5 g and 98.17 g of crude extracts, respectively. Chromatography of the hexane extract over a silica gel column led to the isolation of the triterpene populnoic acid. The oral administration of hydralcoholic, hexane, chloroform and EtOAc extracts (200 mg/kg) decreased the ulcer lesion index (ULI) by 83.15%, 46.87%, 32.2%, 68.12%, respectively. Oral administration of populnoic acid (100 mg/kg) diminished the ULI by 55.29%. All the obtained results were significant in comparison with the negative control, with exception of the chloroform extract.

Vacuum-insulated catalytic converter

DOEpatents

Benson, David K.

2001-01-01

A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

Multi-step-ahead crude oil price forecasting using a hybrid grey wave model

NASA Astrophysics Data System (ADS)

Chen, Yanhui; Zhang, Chuan; He, Kaijian; Zheng, Aibing

2018-07-01

Crude oil is crucial to the operation and economic well-being of the modern society. Huge changes of crude oil price always cause panics to the global economy. There are many factors influencing crude oil price. Crude oil price prediction is still a difficult research problem widely discussed among researchers. Based on the researches on Heterogeneous Market Hypothesis and the relationship between crude oil price and macroeconomic factors, exchange market, stock market, this paper proposes a hybrid grey wave forecasting model, which combines Random Walk (RW)/ARMA to forecast multi-step-ahead crude oil price. More specifically, we use grey wave forecasting model to model the periodical characteristics of crude oil price and ARMA/RW to simulate the daily random movements. The innovation also comes from using the information of the time series graph to forecast crude oil price, since grey wave forecasting is a graphical prediction method. The empirical results demonstrate that based on the daily data of crude oil price, the hybrid grey wave forecasting model performs well in 15- to 20-step-ahead prediction and it always dominates ARMA and Random Walk in correct direction prediction.

Jet fuels from synthetic crudes

NASA Technical Reports Server (NTRS)

Antoine, A. C.; Gallagher, J. P.

1977-01-01

An investigation was conducted to determine the technical problems in the conversion of a significant portion of a barrel of either a shale oil or a coal synthetic crude oil into a suitable aviation turbine fuel. Three syncrudes were used, one from shale and two from coal, chosen as representative of typical crudes from future commercial production. The material was used to produce jet fuels of varying specifications by distillation, hydrotreating, and hydrocracking. Attention is given to process requirements, hydrotreating process conditions, the methods used to analyze the final products, the conditions for shale oil processing, and the coal liquid processing conditions. The results of the investigation show that jet fuels of defined specifications can be made from oil shale and coal syncrudes using readily available commercial processes.

Phytoremediation of crude oil-contaminated soil employing Crotalaria pallida Aiton.

PubMed

Baruah, P; Deka, S; Baruah, P P

2016-06-01

The purpose of the study was to evaluate the phytoremediation potentiality of a herb named Crotalaria pallida which are abundantly grown on crude oil-contaminated soil of oil field situated at upper Assam, India, so that this plant could be used to remediate hydrocarbon from contaminated soil. To evaluate the potentiality of the plant, a pot culture experiment was conducted taking 3 kg of rice field soil mixed with crude oil at a concentration of 10,000 (10 g/kg), 20,000 (20 g/kg), 30,000 (30 g/kg), 40,000 (40 g/kg), 50,000 (50 g/kg), 60,000 (60 g/kg), 70,000 (70 g/kg), 80,000 (80 g/kg), 90,000 (90 g/kg), and 100,000 (100 g/kg) ppm. Ten numbers of healthy seeds of C. pallida were sown in three pots of each concentration for germination, and after 15 days of germination, single healthy seedling in each pot was kept for the study. A control setup was also maintained without adding crude oil. The duration of the experiment was fixed for 6 months. The results showed that uptake of hydrocarbon by the plants was increased with increasing the concentration of crude oil in the soil up to 60,000 ppm. After that, uptake of hydrocarbon by the plants was found to be lower with increasing doses of crude oil concentration. Uptake of hydrocarbon by the shoot was found to be maximum, i.e., 35,018 ppm in 60,000 ppm concentration. Dissipation of total petroleum hydrocarbon (TPH) from the soil was also gradually increased with increasing concentration of crude oil in the soil up to 60,000 ppm. Maximum dissipation, i.e., 78.66 %, occurred in 60,000 ppm concentration of crude oil-mixed soil. The plant could not survive in 100,000 ppm concentration of crude oil-mixed soil. The results also demonstrated that there was a reduction in plant shoot and root biomass with an increase of crude oil concentration. Furthermore, results revealed that the shoot biomass was higher than root biomass in all the treatments.

Comparison of occlusion break responses and vacuum rise times of phacoemulsification systems

PubMed Central

2014-01-01

Background Occlusion break surge during phacoemulsification cataract surgery can lead to potential surgical complications. The purpose of this study was to quantify occlusion break surge and vacuum rise time of current phacoemulsification systems used in cataract surgery. Methods Occlusion break surge at vacuum pressures between 200 and 600 mmHg was assessed with the Infiniti® Vision System, the WhiteStar Signature® Phacoemulsification System, and the Centurion® Vision System using gravity-fed fluidics. Centurion Active FluidicsTM were also tested at multiple intraoperative pressure target settings. Vacuum rise time was evaluated for Infiniti, WhiteStar Signature, Centurion, and Stellaris® Vision Enhancement systems. Rise time to vacuum limits of 400 and 600 mmHg was assessed at flow rates of 30 and 60 cc/minute. Occlusion break surge was analyzed by 2-way analysis of variance. Results The Centurion system exhibited substantially less occlusion break surge than the other systems tested. Surge area with Centurion Active Fluidics was similar to gravity fluidics at an equivalent bottle height. At all Centurion Active Fluidics intraoperative pressure target settings tested, surge was smaller than with Infiniti and WhiteStar Signature. Infiniti had the fastest vacuum rise time and Stellaris had the slowest. No system tested reached the 600-mmHg vacuum limit. Conclusions In this laboratory study, Centurion had the least occlusion break surge and similar vacuum rise times compared with the other systems tested. Reducing occlusion break surge may increase safety of phacoemulsification cataract surgery. PMID:25074069

Wireless Integrated Microelectronic Vacuum Sensor System

NASA Technical Reports Server (NTRS)

Krug, Eric; Philpot, Brian; Trott, Aaron; Lawrence, Shaun

2013-01-01

NASA Stennis Space Center's (SSC's) large rocket engine test facility requires the use of liquid propellants, including the use of cryogenic fluids like liquid hydrogen as fuel, and liquid oxygen as an oxidizer (gases which have been liquefied at very low temperatures). These fluids require special handling, storage, and transfer technology. The biggest problem associated with transferring cryogenic liquids is product loss due to heat transfer. Vacuum jacketed piping is specifically designed to maintain high thermal efficiency so that cryogenic liquids can be transferred with minimal heat transfer. A vacuum jacketed pipe is essentially two pipes in one. There is an inner carrier pipe, in which the cryogenic liquid is actually transferred, and an outer jacket pipe that supports and seals the vacuum insulation, forming the "vacuum jacket." The integrity of the vacuum jacketed transmission lines that transfer the cryogenic fluid from delivery barges to the test stand must be maintained prior to and during engine testing. To monitor the vacuum in these vacuum jacketed transmission lines, vacuum gauge readings are used. At SSC, vacuum gauge measurements are done on a manual rotation basis with two technicians, each using a handheld instrument. Manual collection of vacuum data is labor intensive and uses valuable personnel time. Additionally, there are times when personnel cannot collect the data in a timely fashion (i.e., when a leak is detected, measurements must be taken more often). Additionally, distribution of this data to all interested parties can be cumbersome. To simplify the vacuum-gauge data collection process, automate the data collection, and decrease the labor costs associated with acquiring these measurements, an automated system that monitors the existing gauges was developed by Invocon, Inc. For this project, Invocon developed a Wireless Integrated Microelectronic Vacuum Sensor System (WIMVSS) that provides the ability to gather vacuum

Compost and Crude Humic Substances Produced from Selected Wastes and Their Effects on Zea mays L. Nutrient Uptake and Growth

PubMed Central

Palanivell, Perumal; Susilawati, Kasim; Ahmed, Osumanu Haruna; Majid, Nik Muhamad

2013-01-01

Production of agriculture and timber commodities leads generation of enormous quantity of wastes. Improper disposal of these agroindustrial wastes pollutes the environment. This problem could be reduced by adding value to them. Therefore, a study was carried out to analyse and compare the nutrients content of RS, RH, SD, and EFB of composts and crude humic substances; furthermore, their effect on growth, dry matter production, and nutrient uptake for Zea mays L., and selected soil chemical properties were evaluated. Standard procedures were used to analyze humic acids (HA), crude fulvic acids (CFA), crude humin (CH), soil, dry matter production and nutrient uptake. Sawdust and RS compost matured at 42 and 47 days, respectively, while RH and EFB composts were less matured at 49th day of composting. Rice straw compost had higher ash, N, P, CEC, HA, K, and Fe contents with lower organic matter, total organic carbon, and C/N and C/P ratios. The HA of sawdust compost showed higher carbon, carboxylic, K, and Ca contents compared to those of RS, RH, and EFB. Crude FA of RS compost showed highest pH, total K, Ca, Mg, and Na contents. Crude humin from RS compost had higher contents of ash, N, P, and CEC. Rice straw was superior in compost, CFA, and CH, while sawdust compost was superior in HA. Application of sawdust compost significantly increased maize plants' diameter, height, dry matter production, N, P, and cations uptake. It also reduced N, P, and K based chemical fertilizer use by 90%. Application of CH and the composts evaluated in this study could be used as an alternative for chemical fertilizers in maize cultivation. PMID:24319353

Running vacuum cosmological models: linear scalar perturbations

NASA Astrophysics Data System (ADS)

Perico, E. L. D.; Tamayo, D. A.

2017-08-01

In cosmology, phenomenologically motivated expressions for running vacuum are commonly parameterized as linear functions typically denoted by Λ(H2) or Λ(R). Such models assume an equation of state for the vacuum given by bar PΛ = - bar rhoΛ, relating its background pressure bar PΛ with its mean energy density bar rhoΛ ≡ Λ/8πG. This equation of state suggests that the vacuum dynamics is due to an interaction with the matter content of the universe. Most of the approaches studying the observational impact of these models only consider the interaction between the vacuum and the transient dominant matter component of the universe. We extend such models by assuming that the running vacuum is the sum of independent contributions, namely bar rhoΛ = Σibar rhoΛi. Each Λ i vacuum component is associated and interacting with one of the i matter components in both the background and perturbation levels. We derive the evolution equations for the linear scalar vacuum and matter perturbations in those two scenarios, and identify the running vacuum imprints on the cosmic microwave background anisotropies as well as on the matter power spectrum. In the Λ(H2) scenario the vacuum is coupled with every matter component, whereas the Λ(R) description only leads to a coupling between vacuum and non-relativistic matter, producing different effects on the matter power spectrum.

Stable distribution and long-range correlation of Brent crude oil market

NASA Astrophysics Data System (ADS)

Yuan, Ying; Zhuang, Xin-tian; Jin, Xiu; Huang, Wei-qiang

2014-11-01

An empirical study of stable distribution and long-range correlation in Brent crude oil market was presented. First, it is found that the empirical distribution of Brent crude oil returns can be fitted well by a stable distribution, which is significantly different from a normal distribution. Second, the detrended fluctuation analysis for the Brent crude oil returns shows that there are long-range correlation in returns. It implies that there are patterns or trends in returns that persist over time. Third, the detrended fluctuation analysis for the Brent crude oil returns shows that after the financial crisis 2008, the Brent crude oil market becomes more persistence. It implies that the financial crisis 2008 could increase the frequency and strength of the interdependence and correlations between the financial time series. All of these findings may be used to improve the current fractal theories.

Investigating the characteristic strength of flocs formed from crude and purified Hibiscus extracts in water treatment.

PubMed

Jones, Alfred Ndahi; Bridgeman, John

2016-10-15

The growth, breakage and re-growth of flocs formed using crude and purified seed extracts of Okra (OK), Sabdariffa (SB) and Kenaf (KE) as coagulants and coagulant aids was assessed. The results showed floc size increased from 300 μm when aluminium sulphate (AS) was used as a coagulant to between 696 μm and 722 μm with the addition of 50 mg/l of OK, KE and SB crude samples as coagulant aids. Similarly, an increase in floc size was observed when each of the purified proteins was used as coagulant aid at doses of between 0.123 and 0.74 mg/l. The largest floc sizes of 741 μm, 460 μm and 571 μm were obtained with a 0.123 mg/l dose of purified Okra protein (POP), purified Sabdariffa (PSP) and purified Kenaf (PKP) respectively. Further coagulant aid addition from 0.123 to 0.74 mg/l resulted in a decrease in floc size and strength in POP and PSP. However, an increase in floc strength and reduced d50 size was observed in PKP at a dose of 0.74 mg/l. Flocs produced when using purified and crude extract samples as coagulant aids exhibited high recovery factors and strength. However, flocs exhibited greater recovery post-breakage when the extracts were used as a primary coagulant. It was observed that the combination of purified proteins and AS improved floc size, strength and recovery factors. Therefore, the applications of Hibiscus seeds in either crude or purified form increases floc growth, strength, recoverability and can also reduce the cost associated with the import of AS in developing countries. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Vacuum-assisted closure therapy in the management of lung abscess.

PubMed

Sziklavari, Zsolt; Ried, Michael; Hofmann, Hans-Stefan

2014-09-06

Despite significant advances in the treatment of thoracic infections, complex lung abscess remains a problem in modern thoracic surgery. We describe the novel application of vacuum-assisted closure for the treatment of a lung abscess. The technical details and preliminary results are reported. After the initial failed conservative treatment of an abscess, minimally invasive surgical intervention was performed with vacuum-assisted closure. The vacuum sponges were inserted in the abscess cavity at the most proximal point to the pleural surface. The intercostal space of the chest wall above the entering place was secured by a soft tissue retractor. The level of suction was initially set to 100 mm Hg, with a maximum suction of 125 mm Hg. The sponge was changed once on the 3rd postoperative day. The abscess cavity was rapidly cleaned and decreased in size. The mini-thoracotomy could be closed on the 9th postoperative day. Closure of the cavity was simple, without any short- or long-term treatment failure. This technique reduced the trauma associated with the procedure. The patient was discharged on the 11th postoperative day. Vacuum-assisted closure systems should be considered for widespread use as an alternative option for the treatment of complicated pulmonary abscess in elderly, debilitated, immunocompromised patients after failed conservative treatment.

Monthly Crude Oil and Natural Gas Production Report

EIA Publications

2017-01-01

Crude oil production (including lease condensate) and natural gas production (gross withdrawals) from data collected on Form EIA-914 (Monthly Crude Oil, Lease Condensate, and Natural Gas Production Report) for Federal Offshore Gulf of Mexico, Texas, Louisiana, New Mexico, Oklahoma, Texas, Wyoming, other states and lower 48 states. Alaska data are from the Alaska state government and included to obtain a U.S. total.

Impact of Expanded North Slope of Alaska Crude Oil Production on Oil Flows in the Contiguous United States (Summary)

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

DeRosa, Sean e.; Flanagan, Tatiana Paz

Crude oil produced on the North Slope of Alaska (NSA) is primarily transported on the Trans-Alaska Pipeline System (TAPS) to in-state refineries and the Valdez Marine Terminal in southern Alaska. From the Terminal, crude oil is loaded onto tankers and is transported to export markets or to three major locations along the U.S. West Coast: Anacortes-Ferndale area (Washington), San Francisco Bay area, and Los Angeles area. North Slope of Alaska production has decreased about 75% since the 1980s, which has reduced utilization of TAPS.

14 CFR 29.1433 - Vacuum systems.

Code of Federal Regulations, 2010 CFR

2010-01-01

... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe. (b) Each vacuum air system line and fitting on the discharge side of the pump that might contain...

Vacuum Technology Considerations For Mass Metrology

PubMed Central

Abbott, Patrick J.; Jabour, Zeina J.

2011-01-01

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

Learning and memory promoting effects of crude garlic extract.

PubMed

Mukherjee, Dhrubajyoti; Banerjee, Sugato

2013-12-01

Chronic administration of aged garlic extract has been shown to prevent memory impairment in mice. Acute and chronic (21 days) effects of marketed formulation of crude garlic extract (Lasuna) were evaluated on learning and memory in mice using step down latency (SDL) by passive avoidance response and transfer latency (TL) using elevated plus maze. Scopolamine (0.4 mg/kg, ip) was used to induce amnesia in mice and piracetam (200 mg/kg, ip) served as positive control. In the acute study, Lasuna (65 mg/kg, po) partially reversed the scopolamine-induced amnesia but failed to improve learning and memory in untreated animals. Chronic administration of Lasuna (40 mg/kg/day for 21 days) significantly improved learning both in control and scopolamine induced amnesic animals. Influence of Lasuna on central cholinergic activity and its antioxidant properties were also studied by estimating the cortical acetylcholinesterase (AchE) activity and reduced glutathione (GSH) levels respectively. Chronic administration of Lasuna inhibited AchE, while increasing GSH levels. Thus the results indicate that long-term administration of crude garlic extract may improve learning and memory in mice while the underlying mechanism of action may be attributed to the anti-AchE activity and anti-oxidant property of garlic.

Gas propagation in a liquid helium cooled vacuum tube following a sudden vacuum loss

NASA Astrophysics Data System (ADS)

Dhuley, Ram C.

This dissertation describes the propagation of near atmospheric nitrogen gas that rushes into a liquid helium cooled vacuum tube after the tube suddenly loses vacuum. The loss-of-vacuum scenario resembles accidental venting of atmospheric air to the beam-line of a superconducting radio frequency particle accelerator and is investigated to understand how in the presence of condensation, the in-flowing air will propagate in such geometry. In a series of controlled experiments, room temperature nitrogen gas (a substitute for air) at a variety of mass flow rates was vented to a high vacuum tube immersed in a bath of liquid helium. Pressure probes and thermometers installed on the tube along its length measured respectively the tube pressure and tube wall temperature rise due to gas flooding and condensation. At high mass in-flow rates a gas front propagated down the vacuum tube but with a continuously decreasing speed. Regression analysis of the measured front arrival times indicates that the speed decreases nearly exponentially with the travel length. At low enough mass in-flow rates, no front propagated in the vacuum tube. Instead, the in-flowing gas steadily condensed over a short section of the tube near its entrance and the front appeared to `freeze-out'. An analytical expression is derived for gas front propagation speed in a vacuum tube in the presence of condensation. The analytical model qualitatively explains the front deceleration and flow freeze-out. The model is then simplified and supplemented with condensation heat/mass transfer data to again find the front to decelerate exponentially while going away from the tube entrance. Within the experimental and procedural uncertainty, the exponential decay length-scales obtained from the front arrival time regression and from the simplified model agree.

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

NASA Technical Reports Server (NTRS)

Kleinhenz, Julie; Wilkinson, Allen

2012-01-01

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

Axial bone-socket displacement for persons with a traumatic transtibial amputation: The effect of elevated vacuum suspension at progressive body-weight loads.

PubMed

Darter, Benjamin J; Sinitski, Kirill; Wilken, Jason M

2016-10-01

Elevated vacuum suspension systems use a pump to draw air from the socket with the intent of reducing bone-socket motion as compared to passive suction systems. However, it remains unknown if elevated vacuum suspension systems decrease limb displacement uniformly during transitions from unloaded to full-body-weight support. To compare limb-socket motion between elevated vacuum and passive suction suspension sockets using a controlled loading paradigm. Comparative analysis. Persons with transtibial amputation were assessed while wearing either an elevated vacuum or passive suction suspension socket. Digital video fluoroscopy was used to measure axial bone-socket motion while the limb was loaded in 20% body-weight increments. An analysis of variance model was used to compare between suspension types. Total axial displacement (0%-100% body weight) was significantly lower using the elevated vacuum (vacuum: 1.3 cm, passive suction: 1.8 cm; p < 0.0001). Total displacement decreased primarily due to decreased motion during initial loading (0%-20%; p < 0.0001). Other body-weight intervals were not significantly different between systems. Elevated vacuum suspension reduced axial limb-socket motion by maintaining position of the limb within the socket during unloaded conditions. Elevated vacuum provided no meaningful improvement in limb-socket motion past initial loading. Excessive bone-socket motion contributes to poor residual limb health. Our results suggest elevated vacuum suspensions can reduce this axial displacement. Visual assessment of the images suggests that this occurs through the reduction or elimination of the air pocket between the liner and socket wall while the limb is unloaded. © The International Society for Prosthetics and Orthotics 2015.

14 CFR 29.1433 - Vacuum systems.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a.... (b) Each vacuum air system line and fitting on the discharge side of the pump that might contain...

On-site production of crude glucoamylase for kitchen waste hydrolysis.

PubMed

Wang, Xiao Qiang; Wang, Qun Hui; Liu, Ying Ying; Ma, Hong Zhi

2010-06-01

Kitchen waste from dining rooms accounts for a considerable proportion of municipal solid garbage, and economical recycle ways are needed to be developed. This study investigated glucoamylase production from kitchen waste and the feasibility of kitchen waste hydrolysis by the crude enzymes produced. The key problems of high water content and poor porosity in kitchen waste for glucoamylase production under solid-state fermentation could be solved readily by the addition of corn stover or paddy husk. As a support medium, corn stover was better than paddy husk. Smashed kitchen waste (sKW) mixed with corn stover in the ratio of 3.75 : 1 (dry basis) produced 1838 U g(-1) of glucoamylase by Aspergillus niger UV-60 within 96 h. The enzyme productivity from kitchen waste was over two-fold higher than that from wheat bran with additional nutrients. Without any recovery treatment, the produced glucoamylase could be used directly to hydrolyse sKW slurry. The optimum enzyme dose 8% (crude enzyme/kichen waste, w/w) was not too big, and was sufficient to hydrolyse 10% (dry basis) sKW slurry to produce a maximum amount of reducing sugar of 55.4 g L(-1).

Metals purification by improved vacuum arc remelting

DOEpatents

Zanner, Frank J.; Williamson, Rodney L.; Smith, Mark F.

1994-12-13

The invention relates to improved apparatuses and methods for remelting metal alloys in furnaces, particularly consumable electrode vacuum arc furnaces. Excited reactive gas is injected into a stationary furnace arc zone, thus accelerating the reduction reactions which purify the metal being melted. Additionally, a cooled condensation surface is disposed within the furnace to reduce the partial pressure of water in the furnace, which also fosters the reduction reactions which result in a purer produced ingot. Methods and means are provided for maintaining the stationary arc zone, thereby reducing the opportunity for contaminants evaporated from the arc zone to be reintroduced into the produced ingot.

Vacuum status-display and sector-conditioning programs

NASA Astrophysics Data System (ADS)

Skelly, J.; Yen, S.

1990-08-01

Two programs have been developed for observation and control of the AGS vacuum system, which include the following notable features: (1) they incorporate a graphical user interface and (2) they are driven by a relational database which describes the vacuum system. The vacuum system comprises some 440 devices organized into 28 vacuum sectors. The status-display program invites menu selection of a sector, interrogates the relational database for relevant vacuum devices, acquires live readbacks and posts a graphical display of their status. The sector-conditioning program likewise invites sector selection, produces the same status display and also implements process control logic on the sector devices to pump the sector down from atmospheric pressure to high vacuum over a period extending several hours. As additional devices are installed in the vacuum system, the devices are added to the relational database; these programs then automatically include the new devices.

Working in a Vacuum

ERIC Educational Resources Information Center

Rathey, Allen

2005-01-01

In this article, the author discusses several myths about vacuum cleaners and offers tips on evaluating and purchasing this essential maintenance tool. These myths are: (1) Amps mean performance; (2) Everyone needs high-efficiency particulate air (HEPA): (3) Picking up a "bowling ball" shows cleaning power; (4) All vacuum bags are the same; (5)…

The utilization of crude fish oil (CFO) to increase mudcrab (Scylla serrata) feed quality

NASA Astrophysics Data System (ADS)

Lamid, Mirni; Agustono

2017-02-01

Crude fish oil is one of essential fatty acid sources, which is found in Sardinella lemuru. This research aims to study the quality improvement of mudcrab(Scylla serrata) feed. Four feed formulations were designed by using completely randomized design, including P0 = trash fish + 1% tapioca starch; P1=trash fish + 2.0% crude fish oil + 1% tapioca starch;, P2= trash fish +4.0% crude fish oil + 1% tapioca starch; P3=trash fish + 6.0% crude fish oil + 1% tapioca starch; P4=trash fish +8.0% crude fish oil + 1% tapioca starch, respectively, which were carried out in quadruplicate. This study showed that feed formulation significantly affected crude protein, crude fiber, crude lipid, ash, organic matter and nitrogen free extract and energy of mudcrab. The P2 feed was the best formulation but had a slight different from P3 formulation.

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

NASA Astrophysics Data System (ADS)

Davydov, A.; Sveshnikov, K.; Voronina, Yu.

2018-01-01

Based on the original combination of analytical methods, computer algebra tools and numerical calculations, proposed recently in Refs. 1-3, the nonperturbative vacuum polarization effects in the 2+1D supercritical Dirac-Coulomb system with Z > Zcr,1 are explored. Both the vacuum charge density ρV P(r→) and vacuum energy ℰV P are considered. The main result of the work is that in the overcritical region ℰV P turns out to be a rapidly decreasing function ˜-ηeffZ3/R with ηeff > 0 and R being the size of the external Coulomb source. Due to a lot of details of calculation the whole work is divided into two parts I and II. In the present part I, we consider the evaluation and behavior of the vacuum density ρV P, which further is used in part II for evaluation of the vacuum energy, with emphasis on the renormalization, convergence of the partial expansion for ρV P and behavior of the integral induced charge QV P in the overcritical region.

Argentation chromatography coupled to ultrahigh-resolution mass spectrometry for the separation of a heavy crude oil.

PubMed

Molnárné Guricza, Lilla; Schrader, Wolfgang

2017-02-10

Simplification of highly complex mixtures such as crude oil by using chromatographic methods makes it possible to get more detailed information about the composition of the analyte. Separation by argentation chromatography can be achieved based on the interaction of different strength between the silver ions (Ag + ) immobilized through a spacer on the silica gel surface and the π-bonds of the analytes. Heavy crude oils contain compounds with a high number of heteroatoms (N, O, S) and a high degree of unsaturation thus making them the perfect analyte for argentation chromatography. The direct coupling of argentation chromatography and ultrahigh-resolution mass spectrometry allows to continuously tracking the separation of the many different compounds by retention time and allows sensitive detection on a molecular level. Direct injection of a heavy crude oil into a ultrahigh-resolution mass spectrometer showed components with DBE of up to 25, whereas analytes with DBE of up to 35 could be detected only after separation with argentation chromatography. The reduced complexity achieved by the separation helps increasing the information depth. Copyright © 2016. Published by Elsevier B.V.

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

PubMed Central

Ströbel, Ulrich; Rose-Meierhöfer, Sandra; Öz, Hülya; Brunsch, Reiner

2013-01-01

Progress in sensor technique and electronics has led to a decrease in the costs of electronic and sensor components. In modern dairy farms, having udders in good condition, a lower frequency of udder disease and an extended service life of dairy cows will help ensure competitiveness. The objective of this study was to develop a teat-end vacuum control system with individual quarter actor reaction. Based on a review of the literature, this system is assumed to protect the teat tissue. It reduces the mean teat-end vacuum in the maximum vacuum phase (b) to a level of 20 kPa at a flow rate of 0.25 L/min per quarter. At flow rates higher than 1.50 L/min per quarter, the teat-end vacuum can be controlled to a level of 30 kPa, because in this case it is desirable to have a higher vacuum for the transportation of the milk to the receiver. With this system it is possible for the first time to supply the teat end with low vacuum at low flow rates and with higher vacuum at increasing flow rates in a continuous process with a three second reaction-rate on individual quarter level. This system is completely automated. PMID:23765272

Vacuum system of the compact Energy Recovery Linac

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

Honda, T., E-mail: tohru.honda@kek.jp; Tanimoto, Y.; Nogami, T.

2016-07-27

The compact Energy Recovery Linac (cERL), a test accelerator to establish important technologies demanded for future ERL-based light sources, was constructed in late 2013 at KEK. The accelerator was successfully commissioned in early 2014, and demonstrated beam circulation with energy recovery. In the cERL vacuum system, low-impedance vacuum components are required to circulate high-intensity, low-emittance and short-bunch electron beams. We therefore developed ultra-high-vacuum (UHV)-compatible flanges that can connect beam tubes seamlessly, and employed retractable beam monitors, namely, a movable Faraday cup and screen monitors. In most parts of the accelerator, pressures below 1×10{sup −7} Pa are required to mitigate beam-gasmore » interactions. Particularly, near the photocathode electron gun and the superconducting (SC) cavities, pressures below 1×10{sup −8} Pa are required. The beam tubes in the sections adjoining the SC cavities were coated with non-evaporable getter (NEG) materials, to reduce gas condensation on the cryo-surfaces. During the accelerator commissioning, stray magnetic fields from the permanent magnets of some cold cathode gauges (CCGs) were identified as a source of the disturbance to the beam orbit. Magnetic shielding was specially designed as a remedy for this issue.« less

Study on the Removal of Gases in RH Refining Progress through Experiments Using Vacuum Induction Furnace

NASA Astrophysics Data System (ADS)

Niu, Deliang; Liu, Qingcai; Wang, Zhu; Ren, Shan; Lan, Yuanpei; Xu, Minren

Removal of gas is the major function of RH degasser. To optimize the RH refining craft in Chongqing Iron and Steel Co. Ltd, the degassing effect of RH degasser at different degrees of vacuum was investigated using a vacuum induction furnace. In addition, the effect of processing time on the gas content dissolved in molten steel was also studied. The results showed that degree of vacuum was one of the important factors that determined the degassing efficiency in RH refining process. High vacuum degree is helpful in the removal of gas, especially in the removal of [H] dissolved in molten steel. The processing time could be reduced from 25-30 min to 15 minutes and gas content could also meet the demand of RH refining.

Crude oil desulfurization

NASA Technical Reports Server (NTRS)

Kalvinskas, J. J.; Hsu, G. C.; Ernest, J. B. (Inventor)

1982-01-01

High sulfur crude oil is desulfurized by a low temperature (25-80 C.) chlorinolysis at ambient pressure in the absence of organic solvent or diluent but in the presence of water (water/oil=0.3) followed by a water and caustic wash to remove sulfur and chlorine containing reaction products. The process described can be practiced at a well site for the recovery of desulfurized oil used to generate steam for injection into the well for enhanced oil recovery.

The influences of ambient temperature and crude protein levels on performance and serum biochemical parameters in broilers.

PubMed

Liu, Q W; Feng, J H; Chao, Z; Chen, Y; Wei, L M; Wang, F; Sun, R P; Zhang, M H

2016-04-01

This study was undertaken to investigate the effects of ambient temperature, crude protein levels and their interaction on performance and serum biochemical parameters of broiler chickens. A total of 216 Arbor Acre broiler chickens (108 males and 108 females) were used in a 2 × 3 factorial arrangement and randomly reared at two temperatures (normal temperature: 23 °C; daily cyclic high temperature: 28-32 °C) and fed on three diets with different crude protein levels (153.3, 183.3 or 213.3 g/kg, with constant essential amino acids) from 28 to 42 days of age. Daily cyclic high ambient temperature decreased final body weight, average daily weight gain, average daily feed intake and serum total protein contents (p < 0.001, p < 0.001, p < 0.001, p = 0.008 respectively), but increased feed/gain, mortality, respiratory rate, rectal temperature, serum uric acid contents and serum creatine kinase activity (p = 0.008, p = 0.003, p < 0.0001, p < 0.0001, p < 0.0001, p = 0.003 respectively), irrespective of crude protein levels. At the ambient temperature, reducing crude protein levels resulted in an increase in feed/gain (p < 0.001), but a decrease in serum total protein and uric acid contents. Only serum creatine kinase activity in broiler chickens was interacted by daily cyclic high ambient temperature and dietary crude protein levels (p = 0.003). These results indicated that daily cyclic high ambient temperature had a great effect on performance and serum biochemical parameters in broiler chickens, whereas dietary crude protein levels affected them partially. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

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

NASA Astrophysics Data System (ADS)

Davydov, A.; Sveshnikov, K.; Voronina, Yu.

2018-01-01

Nonperturbative vacuum polarization effects are explored for a supercritical Dirac-Coulomb system with Z > Zcr,1 in 2+1D, based on the original combination of analytical methods, computer algebra and numerical calculations, proposed recently in Refs. 1-3. Both the vacuum charge density ρV P(r→) and vacuum energy ℰV P are considered. Due to a lot of details of calculation the whole work is divided into two parts I and II. Taking account of results, obtained in the part I4 for ρV P, in the present part II, the evaluation of the vacuum energy ℰV P is investigated with emphasis on the renormalization and convergence of the partial expansion for ℰV P. It is shown that the renormalization via fermionic loop turns out to be the universal tool, which removes the divergence of the theory both in the purely perturbative and essentially nonperturbative regimes of the vacuum polarization. The main result of calculation is that for a wide range of the system parameters in the overcritical region ℰV P turns out to be a rapidly decreasing function ˜-ηeffZ3/R with ηeff > 0 and R being the size of the external Coulomb source. To the end the similarity in calculations of ℰV P in 2+1 and 3+1D is discussed, and qualitative arguments are presented in favor of the possibility for complete screening of the classical electrostatic energy of the Coulomb source by the vacuum polarization effects for Z ≫ Zcr,1 in 3+1D.

Quantum vacuum noise in physics and cosmology.

PubMed

Davies, P. C. W.

2001-09-01

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

Crude production still jumping in Libya

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

Wells, M.J.

1969-03-01

With the continued shutdown of the Suez Canal, Libya may become the world's fourth largest crude producer within the next few months, and become the leading Arab oil producing nation. Big field and terminal expansions now on hand for nearly all producing companies will raise crude capacity to over 3.8 million bpd by the end of 1969. The current year also is likely to be marked by some important changes in Libyan petroleum legislation and the basis of crude postings. All this is being reflected in Libya's growing voice in Arab oil councils. The steepness in the upward oil productionmore » curve is such that the 1968 average output of 2,599,800 bpd was a jump of 49.4% over the previous years. This gain raised Libya to sixth among the world's oil producers. A breakdown of production figures shows the amount of oil in barrels produced by the various companies in Libya for 1968. In addition to large capacity expansions now on hand for existing fields, virtually all of the producing companies, there are now several concessionaires which have made field discoveries in the past few months and who are negotiating with neighboring producers in the hopes of tying in with an existing pipeline system.« less

Running vacuum cosmological models: linear scalar perturbations

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

Perico, E.L.D.; Tamayo, D.A., E-mail: elduartep@usp.br, E-mail: tamayo@if.usp.br

In cosmology, phenomenologically motivated expressions for running vacuum are commonly parameterized as linear functions typically denoted by Λ( H {sup 2}) or Λ( R ). Such models assume an equation of state for the vacuum given by P-bar {sub Λ} = - ρ-bar {sub Λ}, relating its background pressure P-bar {sub Λ} with its mean energy density ρ-bar {sub Λ} ≡ Λ/8π G . This equation of state suggests that the vacuum dynamics is due to an interaction with the matter content of the universe. Most of the approaches studying the observational impact of these models only consider the interactionmore » between the vacuum and the transient dominant matter component of the universe. We extend such models by assuming that the running vacuum is the sum of independent contributions, namely ρ-bar {sub Λ} = Σ {sub i} ρ-bar {sub Λ} {sub i} . Each Λ i vacuum component is associated and interacting with one of the i matter components in both the background and perturbation levels. We derive the evolution equations for the linear scalar vacuum and matter perturbations in those two scenarios, and identify the running vacuum imprints on the cosmic microwave background anisotropies as well as on the matter power spectrum. In the Λ( H {sup 2}) scenario the vacuum is coupled with every matter component, whereas the Λ( R ) description only leads to a coupling between vacuum and non-relativistic matter, producing different effects on the matter power spectrum.« less

Effects of ingested crude and dispersed crude oil on thermoregulation in ducks (Anas platyrhynchos)

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

Jenssen, B.M.

1989-02-01

Thermoregulatory effects of ingested doses of Statfjord A crude oil and of this oil mixed with the dispersant Finasol OSR-5 were studied in adult domestic ducks (Anas platyrhynchos) exposed to ambient temperatures of +16 degrees C and -17 degrees C. The data show that ingestion of both the crude and the oil-dispersant mixture resulted in an increased body temperature during exposure to the low ambient temperature (-17 degrees C). Neither contaminant had any effect on body temperature during exposure to +16 degrees C. Ingestion of the contaminants had no effect on metabolic heat production at either ambient temperature. The breastmore » skin temperature of the ducks in both contaminated groups was significantly decreased when the ducks were exposed to the low ambient temperature. This indicates that the increase in body temperature observed in the contaminated ducks at the low ambient temperature is due to an increase in peripheral vasoconstriction.« less

Antimicrobial susceptibility and internalization of Salmonella Typhimurium in vacuum-tumbled marinated beef products.

PubMed

Pokharel, S; Brooks, J C; Martin, J N; Brashears, M M

2016-12-01

As the incidence of multidrug resistance (MDR) Salmonella enterica serotype Typhimurium is increasing, data regarding the antimicrobial interventions and pathogen internalization in marinated meat products are important. This study evaluated the antimicrobial intervention and internalization of Salm. Typhimurium in marinated beef sirloin steaks. Beef bottom sirloin flaps (IMPS #185A; USDA Select) inoculated (10 8  log 10  CFU ml -1 ) with Salm. Typhimurium were sprayed (lactic acid (4%) and buffered vinegar (2%)) prior to vacuum-tumbled marination (0·35% sodium chloride and 0·45% sodium tripolyphosphate) for 30 min. Pathogen presence after antimicrobial spray, vacuum-tumbled marination, and translocation was determined by direct plating on Xylose Lysine Deoxycholate (XLD) agar with tryptic soy agar (TSA) overlay. The data imply varied internalization and antimicrobial susceptibility pattern of Salm. Typhimurium in marinated meat. Lactic acid (4%) spray (P < 0·0001) and buffered vinegar (2%; P < 0·0001) reduced surface populations of Salm. Typhimurium on inoculated beef sirloin flaps prior to vacuum marination. However, lactic acid treated sirloin flaps had greater reductions (~2 log 10  CFU cm -2 ) than buffered vinegar when compared with control prior to vacuum marination. However, the translocation of Salm. Typhimurium following vacuum marination was not influenced (P < 0·333) by the application of a surface organic acid spray prior to marination. As detailed in the Federal Register FSIS final rule (9 CFR part 317), vacuum-marinated, vacuum-tumbled meat products are not designated as 'mechanically tenderized'. As such, the internalization and potential survival of Salmonella spp. in marinated beef products is a major concern. These results highlight the internalization of pathogens in vacuum-tumbled meat products and emphasize the importance of considering these products as nonintact. Similarly, these data confirm the efficacy and utility

Vacuum phonon tunneling.

PubMed

Altfeder, Igor; Voevodin, Andrey A; Roy, Ajit K

2010-10-15

Field-induced phonon tunneling, a previously unknown mechanism of interfacial thermal transport, has been revealed by ultrahigh vacuum inelastic scanning tunneling microscopy (STM). Using thermally broadened Fermi-Dirac distribution in the STM tip as in situ atomic-scale thermometer we found that thermal vibrations of the last tip atom are effectively transmitted to sample surface despite few angstroms wide vacuum gap. We show that phonon tunneling is driven by interfacial electric field and thermally vibrating image charges, and its rate is enhanced by surface electron-phonon interaction.

21 CFR 884.4340 - Fetal vacuum extractor.

Code of Federal Regulations, 2011 CFR

2011-04-01

... means of a suction cup attached to the scalp and is powered by an external vacuum source. This generic type of device may include the cup, hosing, vacuum source, and vacuum control. (b) Classification...

21 CFR 884.4340 - Fetal vacuum extractor.

Code of Federal Regulations, 2010 CFR

2010-04-01

... means of a suction cup attached to the scalp and is powered by an external vacuum source. This generic type of device may include the cup, hosing, vacuum source, and vacuum control. (b) Classification...

Effects of vacuum rapid thermal annealing on the electrical characteristics of amorphous indium gallium zinc oxide thin films

NASA Astrophysics Data System (ADS)

Lee, Hyun-Woo; Cho, Won-Ju

2018-01-01

We investigated the effects of vacuum rapid thermal annealing (RTA) on the electrical characteristics of amorphous indium gallium zinc oxide (a-IGZO) thin films. The a-IGZO films deposited by radiofrequency sputtering were subjected to vacuum annealing under various temperature and pressure conditions with the RTA system. The carrier concentration was evaluated by Hall measurement; the electron concentration of the a-IGZO film increased and the resistivity decreased as the RTA temperature increased under vacuum conditions. In a-IGZO thin-film transistors (TFTs) with a bottom-gate top-contact structure, the threshold voltage decreased and the leakage current increased as the vacuum RTA temperature increased. As the annealing pressure decreased, the threshold voltage decreased, and the leakage current increased. X-ray photoelectron spectroscopy indicated changes in the lattice oxygen and oxygen vacancies of the a-IGZO films after vacuum RTA. At higher annealing temperatures, the lattice oxygen decreased and oxygen vacancies increased, which suggests that oxygen was diffused out in a reduced pressure atmosphere. The formation of oxygen vacancies increased the electron concentration, which consequently increased the conductivity of the a-IGZO films and reduced the threshold voltage of the TFTs. The results showed that the oxygen vacancies and electron concentrations of the a-IGZO thin films changed with the vacuum RTA conditions and that high-temperature RTA treatment at low pressure converted the IGZO thin film to a conductor.

A MODEL FOR DIFFUSION CONTROLLED BIOAVAILABILITY OF CRUDE OIL COMPONENTS

EPA Science Inventory

Crude oil is a complex mixture of several different structural classes of compounds including alkanes, aromatics, heterocyclic polar compounds, and asphaltenes. The rate and extent of microbial degradation of crude oil depends on the interaction between the physical and biochemi...

Cold cathode vacuum gauging system

DOEpatents

Denny, Edward C.

2004-03-09

A vacuum gauging system of the cold cathode type is provided for measuring the pressure of a plurality of separate vacuum systems, such as in a gas centrifuge cascade. Each casing is fitted with a gauge tube assembly which communicates with the vacuum system in the centrifuge casing. Each gauge tube contains an anode which may be in the form of a slender rod or wire hoop and a cathode which may be formed by the wall of the gauge tube. The tube is provided with an insulated high voltage connector to the anode which has a terminal for external connection outside the vacuum casing. The tube extends from the casing so that a portable magnet assembly may be inserted about the tube to provide a magnetic field in the area between the anode and cathode necessary for pressure measurements in a cold cathode-type vacuum gauge arrangement. The portable magnetic assembly is provided with a connector which engages the external high voltage terminal for providing power to the anode within in the gauge tube. Measurement is made in the same manner as the prior cold cathode gauges in that the current through the anode to the cathode is measured as an indication of the pressure. By providing the portable magnetic assembly, a considerable savings in cost, installation, and maintenance of vacuum gauges for pressure measurement in a gas centrifuge cascade is realizable.

Pneumatically Actuated Miniature Peristaltic Vacuum Pumps

NASA Technical Reports Server (NTRS)

Feldman, Sabrina; Feldman, Jason; Svehla, Danielle

2003-01-01

pressure or to a partial vacuum source. The design would be such that the higher pneumatic pressure would be sufficient to push the silicone arches down onto the substrates, blocking the channels. Thus, by connecting pneumatic- actuation channels to the two pneumatic sources in spatial and temporal alternation, waves of opening and closing, equivalent to peristalsis, could be made to move along the pump channels. A pump according to this concept could be manufactured inexpensively. Pneumatic sources (compressors and partial vacuum sources) similar those needed for actuation are commercially available; they typically have masses of .100 g and power demands of the order of several W. In a design-optimization effort, it should be possible to reduce masses and power demands below even these low levels and to integrate pneumatic sources along with the proposed pumps into miniature units with overall dimensions of no more than a few centimeters per side.

Measurement of partial pressures in vacuum technology and vacuum physics

NASA Technical Reports Server (NTRS)

Huber, W. K.

1986-01-01

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

VACUUM TRAP AND VALVE COMBINATION

DOEpatents

Milleron, N.; Levenson, L.

1963-02-19

This patent relates to a vacuum trap and valve combination suitable for use in large ultra-high vacuum systems. The vacuum trap is a chamber having an inlet and outlet opening which may be made to communicate with a chamber to be evacuated and a diffusion pump, respectively. A valve is designed to hermeticaliy seal with inlet opening and, when opened, block the line-of- sight'' between the inlet and outlet openings, while allowing a large flow path between the opened vaive and the side walls of the trap. The interior of the trap and the side of the valve facing the inlet opening are covered with an impurity absorbent, such as Zeolite or activated aluminum. Besides the advantage of combining two components of a vacuum system into one, the present invention removes the need for a baffle between the pump and the chamber to be evacuated. In one use of a specific embodiment of this invention, the transmission probability was 45 and the partial pressure of the pump fluid vapor in the vacuum chamber was at least 100 times lower than its vapor pressure. (AEC)

Crude oil as a microbial seed bank with unexpected functional potentials

PubMed Central

Cai, Man; Nie, Yong; Chi, Chang-Qiao; Tang, Yue-Qin; Li, Yan; Wang, Xing-Biao; Liu, Ze-Shen; Yang, Yunfeng; Zhou, Jizhong; Wu, Xiao-Lei

2015-01-01

It was widely believed that oil is a harsh habitat for microbes because of its high toxicity and hydrophobicity. However, accumulating evidence has revealed the presence of live microbes in crude oil. Therefore, it’s of value to conduct an in-depth investigation on microbial communities in crude oil. To this end, microorganisms in oil and water phases were collected from four oil-well production mixtures in Qinghai Oilfield, China, and analyzed for their taxonomic and functional compositions via pyrosequencing and GeoChip, respectively. Hierarchical clustering of 16S rRNA gene sequences and functional genes clearly separated crude oil and water phases, suggestive of distinct taxonomic and functional gene compositions between crude oil and water phases. Unexpectedly, Pseudomonas dominated oil phase where diverse functional gene groups were identified, which significantly differed from those in the corresponding water phases. Meanwhile, most functional genes were significantly more abundant in oil phase, which was consistent with their important roles in facilitating survival of their host organisms in crude oil. These findings provide strong evidence that crude oil could be a “seed bank” of functional microorganisms with rich functional potentials. This offers novel insights for industrial applications of microbial-enhanced oil recovery and bioremediation of petroleum-polluted environments. PMID:26525361

Measurement of H2S in Crude Oil and Crude Oil Headspace Using Multidimensional Gas Chromatography, Deans Switching and Sulfur-selective Detection

PubMed Central

Heshka, Nicole E.; Hager, Darcy B.

2015-01-01

A method for the analysis of dissolved hydrogen sulfide in crude oil samples is demonstrated using gas chromatography. In order to effectively eliminate interferences, a two dimensional column configuration is used, with a Deans switch employed to transfer hydrogen sulfide from the first to the second column (heart-cutting). Liquid crude samples are first separated on a dimethylpolysiloxane column, and light gases are heart-cut and further separated on a bonded porous layer open tubular (PLOT) column that is able to separate hydrogen sulfide from other light sulfur species. Hydrogen sulfide is then detected with a sulfur chemiluminescence detector, adding an additional layer of selectivity. Following separation and detection of hydrogen sulfide, the system is backflushed to remove the high-boiling hydrocarbons present in the crude samples and to preserve chromatographic integrity. Dissolved hydrogen sulfide has been quantified in liquid samples from 1.1 to 500 ppm, demonstrating wide applicability to a range of samples. The method has also been successfully applied for the analysis of gas samples from crude oil headspace and process gas bags, with measurement from 0.7 to 9,700 ppm hydrogen sulfide. PMID:26709594

Laboratory Validation and Field Assessment of Petroleum Laboratory Technicians' Dermal Exposure to Crude Oil Using a Wipe Sampling Method.

PubMed

Galea, Karen S; Mueller, Will; Arfaj, Ayman M; Llamas, Jose L; Buick, Jennifer; Todd, David; McGonagle, Carolyn

2018-05-21

Crude oil may cause adverse dermal effects therefore dermal exposure is an exposure route of concern. Galea et al. (2014b) reported on a study comparing recovery (wipe) and interception (cotton glove) dermal sampling methods. The authors concluded that both methods were suitable for assessing dermal exposure to oil-based drilling fluids and crude oil but that glove samplers may overestimate the amount of fluid transferred to the skin. We describe a study which aimed to further evaluate the wipe sampling method to assess dermal exposure to crude oil, with this assessment including extended sample storage periods and sampling efficiency tests being undertaken at environmental conditions to mimic those typical of outdoor conditions in Saudi Arabia. The wipe sampling method was then used to assess the laboratory technicians' actual exposure to crude oil during typical petroleum laboratory tasks. Overall, acceptable storage efficiencies up to 54 days were reported with results suggesting storage stability over time. Sampling efficiencies were also reported to be satisfactory at both ambient and elevated temperature and relative humidity environmental conditions for surrogate skin spiked with known masses of crude oil and left up to 4 h prior to wiping, though there was an indication of reduced sampling efficiency over time. Nineteen petroleum laboratory technicians provided a total of 35 pre- and 35 post-activity paired hand wipe samples. Ninety-three percent of the pre-exposure paired hand wipes were less than the analytical limit of detection (LOD), whereas 46% of the post-activity paired hand wipes were less than the LOD. The geometric mean paired post-activity wipe sample measurement was 3.09 µg cm-2 (range 1.76-35.4 µg cm-2). It was considered that dermal exposure most frequently occurred through direct contact with the crude oil (emission) or via deposition. The findings of this study suggest that the wipe sampling method is satisfactory in quantifying

Crude protein and essential amino acid requirements in chicks during the first week posthatch.

PubMed

Sklan, D; Noy, Y

2003-05-01

1. This study examined optimal lysine and sulphur amino acid supply in the first week posthatch in broilers and the relationship between essential amino acids and dietary crude protein during the first week posthatch on performance at 7 d and through marketing. 2. The optimal supply during the 7 d posthatch using a 230 g/kg crude protein diet for sulphur amino acids was 9.1 and for lysine was 10.3-10.8 g/kg with maximal body weight (BW) or feed efficiency as the criteria. 3. Feeding diets with crude protein content ranging from 200 to 260 g/kg with either constant amounts of essential amino acids at different crude protein levels or constant ratios of essential amino acids to crude protein resulted in enhanced performance at 7 but not at 4 d with high protein intake and proportionally increased essential amino acids. 4. Performance on diets with crude protein ranging from 160 to 280 g/kg, with constant ratios of essential amino acid to crude protein, was much enhanced with the high crude protein diets at 7 d. All chicks were transferred to standard diets after 7 d and the BW advantage due to the balanced amino acid-high crude protein diet remained through marketing. 5. Thus increasing essential amino acids in a constant ratio to crude protein enhanced performance during the 7 d posthatch.

Co-processing of olive bagasse with crude rapeseed oil via pyrolysis.

PubMed

Uçar, Suat; Karagöz, Selhan

2017-05-01

The co-pyrolysis of olive bagasse with crude rapeseed oil at different blend ratios was investigated at 500ºC in a fixed bed reactor. The effect of olive bagasse to crude rapeseed oil ratio on the product distributions and properties of the pyrolysis products were comparatively investigated. The addition of crude rapeseed oil into olive bagasse in the co-pyrolysis led to formation of upgraded biofuels in terms of liquid yields and properties. While the pyrolysis of olive bagasse produced a liquid yield of 52.5 wt %, the highest liquid yield of 73.5 wt % was obtained from the co-pyrolysis of olive bagasse with crude rapeseed oil at a blend ratio of 1:4. The bio-oil derived from olive bagasse contained 5% naphtha, 10% heavy naphtha, 30% gas oil, and 55% heavy gas oil. In the case of bio-oil obtained from the co-pyrolysis of olive bagasse with crude rapeseed oil at a blend ratio of 1:4, the light naphtha, heavy naphtha, and light gas oil content increased. This is an indication of the improved characteristics of the bio-oil obtained from the co-processing. The heating value of bio-oil from the pyrolysis of olive bagasse alone was 34.6 MJ kg -1 and the heating values of bio-oils obtained from the co-pyrolysis of olive bagasse with crude rapeseed oil ranged from 37.6 to 41.6 MJ kg -1 . It was demonstrated that the co-processing of waste biomass with crude plant oil is a good alternative to improve bio-oil yields and properties.

Vacuum enhanced cutaneous biopsy instrument

DOEpatents

Collins, Joseph

2000-01-01

A syringe-like disposable cutaneous biopsy instrument equipped with a tubular blade at its lower end, and designed so that a vacuum is created during use, said vacuum serving to retain undeformed a plug of tissue cut from a patient's skin.

Studies of Lubricating Materials in Vacuum

NASA Technical Reports Server (NTRS)

Buckley, D. H.; Johnson, R. L.; Swikert, M. A.

1964-01-01

Lubricating materials for use in a vacuum environment have been the subject of a series of experimental investigations. Evaporation properties were evaluated for solid polymeric compositions. Friction and wear studies explored the behavior during sliding contact for series of polymeric compositions, binary alloys containing soft film-forming phases, complex alloys with film-forming materials, and a burnished MoS2 film. Friction and wear experiments were conducted at 10(exp-9)mm Hg with a 3/16-inch-radius-hemisphere rider specimen sliding on the flat surface of a rotating 2-1/2-inch-diameter disk specimen with materials that had low rates of evaporation. The influence of fillers in polytetrafluoroethylene (PTFE) on decomposition during vacuum friction studies was determined with a mass spectrometer. A real advantage in reducing decomposition and improving friction wear properties is gained by adding fillers (e.g., copper) that improve thermal conductivity through the composite materials. A polyimide and an epoxy-MoS2 composition material were found to have better friction and wear properties than PTFE compositions. A series of alloys (cast binary as well as more complex alloys) that contained microinclusions of potential film-forming material was studied. These materials replaced the normal surface oxides as they were worn away on sliding contact. Iron sulfide, nickel oxide, and tin are typical film-forming materials employed and were demonstrated to be effective in inhibiting surface welding and reducing friction. A burnished MoS2 film applied to type 440-C stainless steel in argon with a rotating soft wire brush had good endurance properties but somewhat higher friction than commercially available bonded films. An oil film applied to the burnished MoS2 markedly reduced its endurance life.

Effect of fabrication parameters on coating properties of tubular solid oxide fuel cell electrolyte prepared by vacuum slurry coating

NASA Astrophysics Data System (ADS)

Son, Hui-Jeong; Song, Rak-Hyun; Lim, Tak-Hyoung; Lee, Seung-Bok; Kim, Sung-Hyun; Shin, Dong-Ryul

The process of vacuum slurry coating for the fabrication of a dense and thin electrolyte film on a porous anode tube is investigated for application in solid oxide fuel cells. 8 mol% yttria stabilized zirconia is coated on an anode tube by vacuum slurry-coating process as a function of pre-sintering temperature of the anode tube, vacuum pressure, slurry concentration, number of coats, and immersion time. A dense electrolyte layer is formed on the anode tube after final sintering at 1400 °C. With decrease in the pre-sintering temperature of the anode tube, the grain size of the coated electrolyte layer increases and the number of surface pores in the coating layer decreases. This is attributed to a reduced difference in the respective shrinkage of the anode tube and the electrolyte layer. The thickness of the coated electrolyte layer increases with the content of solid powder in the slurry, the number of dip-coats, and the immersion time. Although vacuum pressure has no great influence on the electrolyte thickness, higher vacuum produces a denser coating layer, as confirmed by low gas permeability and a reduced number of defects in the coating layer. A single cell with the vacuum slurry coated electrolyte shows a good performance of 620 mW cm -2 (0.7 V) at 750 °C. These experimental results indicate that the vacuum slurry-coating process is an effective method to fabricate a dense thin film on a porous anode support.

7 CFR 29.3512 - Crude.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Crude. 29.3512 Section 29.3512 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... of extreme immaturity. A similar condition may result from firekill, sunburn, or sunscald. Any leaf...

7 CFR 29.1010 - Crude.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Crude. 29.1010 Section 29.1010 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... of extreme immaturity. A similar condition may result from fire-kill, sunburn, or sunscald. Any leaf...

Inferential control -- Part 1: Crude unit advanced controls pass accuracy and repeatability tests

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

San, Y.P.; Landells, K.C.; Mackay, D.C.

1994-11-28

An inferential model is one that provides a quality for which an analyzer is not available. This type of model uses readily available physical measurements -- such as temperatures, pressures, and flow rates -- to infer a quality such as kerosine flash point. The No. 2 crude distillation unit (CDU-2) at Singapore Refining Co. Pte. Ltd.'s Pulau Merlimau refinery has a nominal 130,000 b/d capacity. It produces naphtha, kerosine, diesel, and residue products from a wide range of crude blends. Over the past 12 months, extensive advanced control applications have been implemented on the unit. This first of two articlesmore » will describe the control system and its implementation. The second will outline the project's achievements, including reduced quality giveaway and increased profits. The paper describes background of the company and unit, the process, project implementation, the Infer model, model tuning, closed-loop control, feed rate maximization, and economic monitoring.« less

33 CFR 157.162 - Crude oil washing during a voyage.

Code of Federal Regulations, 2010 CFR

2010-07-01

... OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Cow Operations § 157.162 Crude oil washing during a voyage. The master of a tank vessel having a COW system under § 157.10(e), § 157.10a(a)(2), or...

Ex-situ bioremediation of crude oil in soil, a comparative kinetic analysis.

PubMed

Mohajeri, Leila; Aziz, Hamidi Abdul; Isa, Mohamed Hasnain; Zahed, Mohammad Ali; Mohajeri, Soraya

2010-07-01

Weathered crude oil (WCO) removals in shoreline sediment samples were monitored for 60 days in bioremediation experimentation. Experimental modeling was carried out using statistical design of experiments. At optimum conditions maximum of 83.13, 78.06 and 69.92% WCO removals were observed for 2, 16 and 30 g/kg initial oil concentrations, respectively. Significant variations in the crude oil degradation pattern were observed with respect to oil, nutrient and microorganism contents. Crude oil bioremediation were successfully described by a first-order kinetic model. The study indicated that the rate of hydrocarbon biodegradation increased with decrease of crude oil concentrations.

Vapor-barrier Vacuum Isolation System

NASA Technical Reports Server (NTRS)

Weinstein, Leonard M. (Inventor); Taminger, Karen M. (Inventor)

2014-01-01

A system includes a collimated beam source within a vacuum chamber, a condensable barrier gas, cooling material, a pump, and isolation chambers cooled by the cooling material to condense the barrier gas. Pressure levels of each isolation chamber are substantially greater than in the vacuum chamber. Coaxially-aligned orifices connect a working chamber, the isolation chambers, and the vacuum chamber. The pump evacuates uncondensed barrier gas. The barrier gas blocks entry of atmospheric vapor from the working chamber into the isolation chambers, and undergoes supersonic flow expansion upon entering each isolation chamber. A method includes connecting the isolation chambers to the vacuum chamber, directing vapor to a boundary with the working chamber, and supersonically expanding the vapor as it enters the isolation chambers via the orifices. The vapor condenses in each isolation chamber using the cooling material, and uncondensed vapor is pumped out of the isolation chambers via the pump.

Crude oil price analysis and forecasting based on variational mode decomposition and independent component analysis

NASA Astrophysics Data System (ADS)

E, Jianwei; Bao, Yanling; Ye, Jimin

2017-10-01

As one of the most vital energy resources in the world, crude oil plays a significant role in international economic market. The fluctuation of crude oil price has attracted academic and commercial attention. There exist many methods in forecasting the trend of crude oil price. However, traditional models failed in predicting accurately. Based on this, a hybrid method will be proposed in this paper, which combines variational mode decomposition (VMD), independent component analysis (ICA) and autoregressive integrated moving average (ARIMA), called VMD-ICA-ARIMA. The purpose of this study is to analyze the influence factors of crude oil price and predict the future crude oil price. Major steps can be concluded as follows: Firstly, applying the VMD model on the original signal (crude oil price), the modes function can be decomposed adaptively. Secondly, independent components are separated by the ICA, and how the independent components affect the crude oil price is analyzed. Finally, forecasting the price of crude oil price by the ARIMA model, the forecasting trend demonstrates that crude oil price declines periodically. Comparing with benchmark ARIMA and EEMD-ICA-ARIMA, VMD-ICA-ARIMA can forecast the crude oil price more accurately.

Cytotoxic Activity and Antiproliferative Effects of Crude Skin Secretion from Physalaemus nattereri (Anura: Leptodactylidae) on in vitro Melanoma Cells

PubMed Central

Cruz e Carvalho, Andréa; Prías Márquez, César Augusto; Azevedo, Ricardo Bentes; Joanitti, Graziella Anselmo; Pires Júnior, Osmindo Rodrigues; Fontes, Wagner; Castro, Mariana S.

2015-01-01

Anuran secretions are rich sources of bioactive molecules, including antimicrobial and antitumoral compounds. The aims of this study were to investigate the therapeutic potential of Physalaemus nattereri skin secretion against skin cancer cells, and to assess its cytotoxic action mechanisms on the murine melanoma cell line B16F10. Our results demonstrated that the crude secretion reduced the viability of B16F10 cells, causing changes in cell morphology (e.g., round shape and structure shrinkage), reduction in mitochondrial membrane potential, increase in phosphatidylserine exposure, and cell cycle arrest in S-phase. Together, these changes suggest that tumor cells die by apoptosis. This skin secretion was also subjected to chromatographic fractioning using RP-HPLC, and eluted fractions were assayed for antiproliferative and antibacterial activities. Three active fractions showed molecular mass components in a range compatible with peptides. Although the specific mechanisms causing the reduced cell viability and cytotoxicity after the treatment with crude secretion are still unknown, it may be considered that molecules, such as the peptides found in the secretion, are effective against B16F10 tumor cells. Considering the growing need for new anticancer drugs, data presented in this study strongly reinforce the validity of P. nattereri crude secretion as a rich source of new anticancer molecules. PMID:26457717

Cytotoxic Activity and Antiproliferative Effects of Crude Skin Secretion from Physalaemus nattereri (Anura: Leptodactylidae) on in vitro Melanoma Cells.

PubMed

Cruz e Carvalho, Andréa; Márquez, César Augusto Prías; Azevedo, Ricardo Bentes; Joanitti, Graziella Anselmo; Pires Júnior, Osmindo Rodrigues; Fontes, Wagner; Castro, Mariana S

2015-10-08

Anuran secretions are rich sources of bioactive molecules, including antimicrobial and antitumoral compounds. The aims of this study were to investigate the therapeutic potential of Physalaemus nattereri skin secretion against skin cancer cells, and to assess its cytotoxic action mechanisms on the murine melanoma cell line B16F10. Our results demonstrated that the crude secretion reduced the viability of B16F10 cells, causing changes in cell morphology (e.g., round shape and structure shrinkage), reduction in mitochondrial membrane potential, increase in phosphatidylserine exposure, and cell cycle arrest in S-phase. Together, these changes suggest that tumor cells die by apoptosis. This skin secretion was also subjected to chromatographic fractioning using RP-HPLC, and eluted fractions were assayed for antiproliferative and antibacterial activities. Three active fractions showed molecular mass components in a range compatible with peptides. Although the specific mechanisms causing the reduced cell viability and cytotoxicity after the treatment with crude secretion are still unknown, it may be considered that molecules, such as the peptides found in the secretion, are effective against B16F10 tumor cells. Considering the growing need for new anticancer drugs, data presented in this study strongly reinforce the validity of P. nattereri crude secretion as a rich source of new anticancer molecules.

7 CFR 58.423 - Cheese vacuumizing chamber.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Cheese vacuumizing chamber. 58.423 Section 58.423 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....423 Cheese vacuumizing chamber. The vacuum chamber shall be satisfactorily constructed and maintained...

7 CFR 58.423 - Cheese vacuumizing chamber.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 3 2011-01-01 2011-01-01 false Cheese vacuumizing chamber. 58.423 Section 58.423 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards....423 Cheese vacuumizing chamber. The vacuum chamber shall be satisfactorily constructed and maintained...

Dynamics of emulsification and demulsification of water in crude oil emulsions

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

Bhardwaj, A.; Hartland, S.

1994-05-01

The effect of aging on the crude oil/water interface has been studied, and the slow buildup of natural surfactants present in the crude oil at the interface was observed. Interfacial tension data and microvideography were used to evaluate the buildup of surface concentration. The methodology adopted in this work permits the calculation of the actual surface excess of natural surfactants at the crude oil/water interface, without having to isolate them from the crude oil and without knowing their bulk molar concentration. The rate of adsorption of demulsifier at the interface was determined by measurement of the dynamic interfacial tension bymore » a microprocessor-controlled drop volume method apparatus. Temperature, concentration, and nature of the medium (crude oil or brine) were found to be very important parameters governing adsorption of demulsifier at the interface. Diffusion of the emulsifier to the oil/water interface was much slower when demulsifier was present in the oil phase than when it was present in the water phase.« less

Effect of crude and pure glycerol on biomass production and trehalose accumulation by Propionibacterium freudenreichii ssp. shermanii 1.

PubMed

Pawlicka-Kaczorowska, Joanna; Czaczyk, Katarzyna

2017-01-01

The dairy propionibacteria, which are traditionally used for the production of Swiss cheeses, are able to synthesize valuable biomolecules, e.g. B group vitamins, propionic acid, and trehalose with unique chemical and physical properties. Both, dairy propionibacteria cells and trehalose, have found many applications as attractive and effective components in food, beauty and health care products. This study confirmed the ability of several strains from the Propionibacterium genus to create trehalose from glycerol. The research aimed to investigate the effect of crude and pure glycerol on biomass production and on trehalose accumulation by Propionibacterium freudenreichii ssp. shermanii 1. The results indicated that the capacity for trehalose accumulation by Propionibacterium spp. was strain dependent. Propionibacterium freudenreichii ssp. shermanii 1 was able to grow on crude glycerol. For both, pure and crude glycerol, the highest amount of dry biomass leveled off at about 4 g/L. While the use of crude glycerol had no effect on the final concentration of biomass, it reduced the accumulation of trehalose in the cells. An increase in the concentration of carbon source (2-8%) resulted in more than a 5-fold rise in trehalose production. The highest trehalose concentration of 195.04 mg/L was obtained with cultures of the said strain supplemented to 8% with pure glycerol.

7 CFR 29.2511 - Crude.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Crude. 29.2511 Section 29.2511 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... leaves are usually hard and slick as a result of extreme immaturity. A similar condition may result from...

Engineering Matter Interactions Using Squeezed Vacuum

NASA Astrophysics Data System (ADS)

Zeytinoǧlu, Sina; Imamoǧlu, Ataç; Huber, Sebastian

2017-04-01

Virtually all interactions that are relevant for atomic and condensed matter physics are mediated by quantum fluctuations of the electromagnetic field vacuum. Consequently, controlling the vacuum fluctuations can be used to engineer the strength and the range of interactions. Recent experiments have used this premise to demonstrate novel quantum phases or entangling gates by embedding electric dipoles in photonic cavities or wave guides, which modify the electromagnetic fluctuations. Here, we show theoretically that the enhanced fluctuations in the antisqueezed quadrature of a squeezed vacuum state allow for engineering interactions between electric dipoles without the need for a photonic structure. Thus, the strength and range of the interactions can be engineered in a time-dependent way by changing the spatial profile of the squeezed vacuum in a traveling-wave geometry, which also allows the implementation of chiral dissipative interactions. Using experimentally realized squeezing parameters and including realistic losses, we predict single-atom cooperativities C of up to 10 for the squeezed-vacuum-enhanced interactions.

MERCURY IN CRUDE OIL PROCESSED IN THE UNITED STATES (2004)

EPA Science Inventory

The mean and range of concentrations of mercury in crude oil processed in the U.S. were investigated using two analytical methods. The sample ensemble consisted of 329 samples from 170 separate crude oil streams that are processed by U.S. refineries. Samples were retrieved imme...

Progressive response of large intestinal bacterial community and fermentation to the stepwise decrease of dietary crude protein level in growing pigs.

PubMed

Peng, Yu; Yu, Kaifan; Mu, Chunlong; Hang, Suqin; Che, Lianqiang; Zhu, Weiyun

2017-07-01

The study aimed to determine the effects of reduction of dietary crude protein (CP) level with balanced essential amino acids (EAA) on intestinal bacteria and their metabolites of growing pigs. Forty pigs (initial BW 13.50 ± 0.50 kg, 45 ± 2 days of age) were randomly assigned to four dietary treatments containing CP levels at 20.00% (normal crude protein, NP); 17.16% (medium crude protein, MP); 15.30% (low crude protein, LP); and 13.90% (extremely low crude protein, ELP), respectively. Crystalline AAs were added to meet the EAA requirement of pigs. After 4-week feeding, eight pigs per treatment (n = 8) were randomly selected and slaughtered for sampling of ileal, cecal, and colonic digesta and mucosa. Pigs with moderately reduced CP level had increased bacterial diversity, with the Shannon diversity indices for the colon digesta in the LP group and mucosa in the MP and LP groups significantly (P < 0.05) higher than those in the NP and ELP groups. As the CP level reduces, the Bifidobacterium population were linearly decreased (P < 0.05) both in ileum, cecum, and colon, and the ELP group had the lowest Bifidobacterium population in the cecum and colon, with its value significantly lower than NP and MP groups (P < 0.05). However, the ELP group had the highest population of Escherichia coli in the colon, with its value significantly higher than the LP group (P < 0.05). For bacterial metabolites, as CP level decreased, total short-chain fatty acid (T-SCFA), acetate, and butyrate were linearly increased (linear, P < 0.05) in the ileum, while all SCFAs except formate in the cecum and T-SCFA and acetate in the colon, were linearly decreased (P < 0.05). Reducing CP level led to a linear decrease of microbial crude protein (MCP) in the ileum (P < 0.05) and ammonia in all intestine segments (P < 0.05). The spermidine in cecum and total amines, cadaverine, methylamine, and spermidine in colon were shown a quadratic change (P < 0.05) as dietary CP

Lightweight Vacuum Jacket for Cryogenic Insulation. Volume 1

NASA Technical Reports Server (NTRS)

Barclay, D. L.; Bell, J. E.; Brogren, E. W.; Straayer, J. W.

1975-01-01

The feasibility of producing a lightweight vacuum jacket using state-of-the-art technology and materials was examined. Design and analytical studies were made on a full-scale, orbital maneuvering system fuel tank. Preliminary design details were made for the tank assembly, including an optimized vacuum jacket and multilayer insulation system. A half-scale LH2 test model was designed and fabricated, and a force/stiffness proof test was conducted on the vacuum jacket. A vacuum leak rate of .000001 atmosphere ml of helium per second was measured, approximately 1500 hours of vacuum pressure were sustained, and 29 vacuum-pressure cycles were experienced prior to failure.

7 CFR 305.29 - Vacuum heat treatment schedule.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 5 2010-01-01 2010-01-01 false Vacuum heat treatment schedule. 305.29 Section 305.29... SERVICE, DEPARTMENT OF AGRICULTURE PHYTOSANITARY TREATMENTS Heat Treatments § 305.29 Vacuum heat treatment... vacuum at 8 hours. Maintain the vacuum until the end of the treatment. Gradually increase the temperature...

Biodegradation of marine crude oil pollution using a salt-tolerant bacterial consortium isolated from Bohai Bay, China.

PubMed

Li, Xinfei; Zhao, Lin; Adam, Mohamed

2016-04-15

This study aims at constructing an efficient bacterial consortium to biodegrade crude oil spilled in China's Bohai Sea. In this study, TCOB-1 (Ochrobactrum), TCOB-2 (Brevundimonas), TCOB-3 (Brevundimonas), TCOB-4 (Bacillus) and TCOB-5 (Castellaniella) were isolated from Bohai Bay. Through the analysis of hydrocarbon biodegradation, TCOB-4 was found to biodegrade more middle-chain n-alkanes (from C17 to C23) and long-chain n-alkanes (C31-C36). TCOB-5 capable to degrade more n-alkanes including C24-C30 and aromatics. On the basis of complementary advantages, TCOB-4 and TCOB-5 were chosen to construct a consortium which was capable of degrading about 51.87% of crude oil (2% w/v) after 1week of incubation in saline MSM (3% NaCl). It is more efficient compared with single strain. In order to biodegrade crude oil, the construction of bacterial consortia is essential and the principle of complementary advantages could reduce competition between microbes. Copyright © 2016. Published by Elsevier Ltd.

[The evolution of vacuum extraction in obstetrics].

PubMed

Nikolov, A

2010-01-01

Vacuum extraction is one of the methods for assisted vaginal delivery. In this article the evolution of vacuum extraction in obstetrics is been discussed. Historical facts and data from the invention up to state-of-the-art vacuum systems in modern obstetrics are presented.

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

PubMed Central

Major, Matthew J.; Caldwell, Ryan; Fatone, Stefania

2015-01-01

Vacuum-assisted suspension (VAS) of prosthetic sockets utilizes a pump to evacuate air from between the prosthetic liner and socket, and are available as mechanical or electric systems. This technical note describes a hybrid pump that benefits from the advantages of mechanical and electric systems, and evaluates a prototype as proof-of-concept. Cyclical bench testing of the hybrid pump mechanical system was performed using a materials testing system to assess the relationship between compression cycles and vacuum pressure. Phase 1 in vivo testing of the hybrid pump was performed by an able-bodied individual using prosthesis simulator boots walking on a treadmill, and phase 2 involved an above-knee prosthesis user walking with the hybrid pump and a commercial electric pump for comparison. Bench testing of 300 compression cycles produced a maximum vacuum of 24 in-Hg. In vivo testing demonstrated that the hybrid pump continued to pull vacuum during walking, and as opposed to the commercial electric pump, did not require reactivation of the electric system during phase 2 testing. The novelty of the hybrid pump is that while the electric system provides rapid, initial vacuum suspension, the mechanical system provides continuous air evacuation while walking to maintain suspension without reactivation of the electric system, thereby allowing battery power to be reserved for monitoring vacuum levels. PMID:27462383

Effects of Ultralow Oxygen and Vacuum Treatments on Bed Bug (Heteroptera: Cimicidae) Survival.

PubMed

Liu, Yong-Biao; Haynes, Kenneth F

2016-04-22

Control of bed bugs is problematic, balancing among efficacy, safety, and cost. In this study, ultralow oxygen (ULO) and vacuum treatments were tested on bed bugs to develop a safer, effective, and environmentally friendly solution to kill bed bugs on infested items. ULO treatments were established by flushing sealed enclosures with nitrogen. All life stages of bed bugs were found to be susceptible to ULO and vacuum treatments, and efficacy of the treatments increased with reduced oxygen levels, increased treatment time, and temperature. In the ULO treatments, 100% mortality of bed bug nymphs and adults and >98% mortality of bed bug eggs were achieved in the 8-h treatment under 0.1% O 2 atmosphere at 30°C. Different levels of vacuum that yielded different oxygen levels were tested on all life stages of bed bugs. The susceptibility of different stages to vacuum treatments increased from nymphs to adults to eggs. Complete control of all life stages was achieved in 12 h under -982 mbar (-29.0 inHg) vacuum at 30°C. This study demonstrated that bed bugs were very susceptible to low oxygen stresses and ULO and vacuum treatments have potential to be used as effective and safe treatments to decontaminate bed bug-infested removable objects. Published by Oxford University Press on behalf of Entomological Society of America 2016.This work is written by US Government employees and is in the public domain in the United States.

Gravitational collapse and the vacuum energy

NASA Astrophysics Data System (ADS)

Campos, M.

2014-03-01

To explain the accelerated expansion of the universe, models with interacting dark components (dark energy and dark matter) have been considered recently in the literature. Generally, the dark energy component is physically interpreted as the vacuum energy of the all fields that fill the universe. As the other side of the same coin, the influence of the vacuum energy on the gravitational collapse is of great interest. We study such collapse adopting different parameterizations for the evolution of the vacuum energy. We discuss the homogeneous collapsing star fluid, that interacts with a vacuum energy component, using the stiff matter case as example. We conclude this work with a discussion of the Cahill-McVittie mass for the collapsed object.

Gravitational baryogenesis in running vacuum models

NASA Astrophysics Data System (ADS)

Oikonomou, V. K.; Pan, Supriya; Nunes, Rafael C.

2017-08-01

We study the gravitational baryogenesis mechanism for generating baryon asymmetry in the context of running vacuum models. Regardless of whether these models can produce a viable cosmological evolution, we demonstrate that they produce a nonzero baryon-to-entropy ratio even if the universe is filled with conformal matter. This is a sound difference between the running vacuum gravitational baryogenesis and the Einstein-Hilbert one, since in the latter case, the predicted baryon-to-entropy ratio is zero. We consider two well known and most used running vacuum models and show that the resulting baryon-to-entropy ratio is compatible with the observational data. Moreover, we also show that the mechanism of gravitational baryogenesis may constrain the running vacuum models.

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

PubMed

Zhou, Yihui; Wu, Wenbiao; Qiu, Keqiang

2010-11-01

In this research, a two-step process consisting of vacuum pyrolysis and vacuum centrifugal separation was employed to treat waste printed circuit boards (WPCBs). Firstly, WPCBs were pyrolysed under vacuum condition at 600 °C for 30 min in a lab-scale reactor. Then, the obtained pyrolysis residue was heated under vacuum until the solder was melted, and then the molten solder was separated from the pyrolysis residue by the centrifugal force. The results of vacuum pyrolysis showed that the type-A of WPCBs (the base plates of which was made from cellulose paper reinforced phenolic resin) pyrolysed to form an average of 67.97 wt.% residue, 27.73 wt.% oil, and 4.30 wt.% gas; and pyrolysis of the type-B of WPCBs (the base plates of which was made from glass fiber reinforced epoxy resin) led to an average mass balance of 72.20 wt.% residue, 21.45 wt.% oil, and 6.35 wt.% gas. The results of vacuum centrifugal separation showed that the separation of solder was complete when the pyrolysis residue was heated at 400 °C, and the rotating drum was rotated at 1200 rpm for 10 min. The pyrolysis oil and gas can be used as fuel or chemical feedstock after treatment. The pyrolysis residue after solder separation contained various metals, glass fibers and other inorganic materials, which could be recycled for further processing. The recovered solder can be reused directly and it can also be a good resource of lead and tin for refining. Copyright © 2010 Elsevier Ltd. All rights reserved.

Diffraction-limited storage-ring vacuum technology

PubMed Central

Al-Dmour, Eshraq; Ahlback, Jonny; Einfeld, Dieter; Tavares, Pedro Fernandes; Grabski, Marek

2014-01-01

Some of the characteristics of recent ultralow-emittance storage-ring designs and possibly future diffraction-limited storage rings are a compact lattice combined with small magnet apertures. Such requirements present a challenge for the design and performance of the vacuum system. The vacuum system should provide the required vacuum pressure for machine operation and be able to handle the heat load from synchrotron radiation. Small magnet apertures result in the conductance of the chamber being low, and lumped pumps are ineffective. One way to provide the required vacuum level is by distributed pumping, which can be realised by the use of a non-evaporable getter (NEG) coating of the chamber walls. It may not be possible to use crotch absorbers to absorb the heat from the synchrotron radiation because an antechamber is difficult to realise with such a compact lattice. To solve this, the chamber walls can work as distributed absorbers if they are made of a material with good thermal conductivity, and distributed cooling is used at the location where the synchrotron radiation hits the wall. The vacuum system of the 3 GeV storage ring of MAX IV is used as an example of possible solutions for vacuum technologies for diffraction-limited storage rings. PMID:25177979

Carotenoid-cleavage activities of crude enzymes from Pandanous amryllifolius.

PubMed

Ningrum, Andriati; Schreiner, Matthias

2014-11-01

Carotenoid degradation products, known as norisoprenoids, are aroma-impact compounds in several plants. Pandan wangi is a common name of the shrub Pandanus amaryllifolius. The genus name 'Pandanus' is derived from the Indonesian name of the tree, pandan. In Indonesia, the leaves from the plant are used for several purposes, e.g., as natural colorants and flavor, and as traditional treatments. The aim of this study was to determine the cleavage of β-carotene and β-apo-8'-carotenal by carotenoid-cleavage enzymes isolated from pandan leaves, to investigate dependencies of the enzymatic activities on temperature and pH, to determine the enzymatic reaction products by using Headspace Solid Phase Microextraction Gas Chromatography/Mass Spectrophotometry (HS-SPME GC/MS), and to investigate the influence of heat treatment and addition of crude enzyme on formation of norisoprenoids. Crude enzymes from pandan leaves showed higher activity against β-carotene than β-apo-8'-carotenal. The optimum temperature of crude enzymes was 70°, while the optimum pH value was 6. We identified β-ionone as the major volatile reaction product from the incubations of two different carotenoid substrates, β-carotene and β-apo-8'-carotenal. Several treatments, e.g., heat treatment and addition of crude enzymes in pandan leaves contributed to the norisoprenoid content. Our findings revealed that the crude enzymes from pandan leaves with carotenoid-cleavage activity might provide a potential application, especially for biocatalysis, in natural-flavor industry. Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich.

Biosurfactant production by Mucor circinelloides on waste frying oil and possible uses in crude oil remediation.

PubMed

Hasanizadeh, Parvin; Moghimi, Hamid; Hamedi, Javad

2017-10-01

Biosurfactants are biocompatible surface active agents which many microorganisms produce. This study investigated the production of biosurfactants by Mucor circinelloides. The effects of different factors on biosurfactant production, including carbon sources and concentrations, nitrogen sources, and iron (II) concentration, were studied and the optimum condition determined. Finally, the strain's ability to remove the crude oil and its relationship with biosurfactant production was evaluated. The results showed that M. circinelloides could reduce the surface tension of the culture medium to 26.6 mN/m and create a clear zone of 12.9 cm diameter in an oil-spreading test. The maximum surface tension reduction was recorded 3 days after incubation. The optimum condition for biosurfactant production was achieved in the presence of 8% waste frying oil as a carbon source, 2 g/L yeast extract as a nitrogen source, and 0.01 mM FeSO 4 . M. circinelloides could consume 8% waste frying oil in 5 days of incubation, and 87.6% crude oil in 12 days of incubation. A direct correlation was observed between oil degradation and surface tension reduction in the first 3 days of fungal growth. The results showed that the waste frying oil could be recommended as an inexpensive oily waste substance for biosurfactant production, and M. circinelloides could have the potential to treat waste frying oil. According to the results, the produced crude biosurfactant or fungal strain could be directly used for the mycoremediation of crude oil contamination in oil fields.

Solids precipitation in crude oils, gas-to-liquids and their blends

NASA Astrophysics Data System (ADS)

Ramanathan, Karthik

Gas-to-liquids (GTL) liquids are obtained from syngas by the Fischer-Tropsch synthesis. The blending of GTL liquids produced from natural gas/coal reserves and crude oils is a possibility in the near future for multiple reasons. Solids precipitation is a major problem in pipelines and refineries leading to significant additional operating costs. The effect of the addition of a paraffinic GTL liquid to crude oils on solids precipitation was investigated in this study. A Fourier transform infrared (FT-IR) spectroscopic technique was used to obtain solid-liquid equilibria (SLE) data for the various samples. The SLE of multiple systems of model oils composed of n-alkanes was investigated preliminarily. Blends of a model oil simulating a GTL liquid composition and a crude oil showed that the wax precipitation temperature (WPT) decreased upon blending. Three crude oils from different geographic regions (Alaskan North Slope, Colorado and Venezuela) and a laboratory-produced GTL liquid were used in the preparation of blends with five different concentrations of the GTL liquid. The wax precipitation temperatures of the blends were found to decrease with the increasing addition of the GTL liquid for all the oils. This effect was attributed to the solvent effect of the low molecular weight-paraffinic GTL liquid on the crude oils. The weight percent solid precipitated that was estimated as a function of temperature did not show a uniform trend for the set of crude oils. The asphaltene onset studies done on the blends with near-infrared spectroscopy indicated that the addition of GTL liquid could have a stabilizing effect on the asphaltenes in some oils. Analytical techniques such as distillation, solvent separation, HPLC, GC, and GPC were used to obtain detailed composition data on the samples. Two sets of compositional data with 49 and 86 pseudo-components were used to describe the three crude oils used in the blending work. The wax precipitation was calculated using a

Nonlinear joint dynamics between prices of crude oil and refined products

NASA Astrophysics Data System (ADS)

Zhang, Tao; Ma, Guofeng; Liu, Guangsheng

2015-02-01

In this paper, we investigate the relationships between crude oil and refined product prices. We find that nonlinear correlations are stronger in the long-term than in the short-term. Crude oil and product prices are cointegrated and financial crisis in 2007-2008 caused a structural break of the cointegrating relationship. Moreover, different from the findings in most studies, we reveal that the relationships are almost symmetric based on a threshold error correction model. The so-called 'asymmetric relationships' are caused by some outliers and financial crisis. Most of the time, crude oil prices play the major role in the adjustment process of the long-term equilibrium. However, refined product prices dominated crude oil prices during the period of financial crisis. Important policy and risk management implications can be learned from the empirical findings.

Volatile hydrocarbons inhibit methanogenic crude oil degradation

PubMed Central

Sherry, Angela; Grant, Russell J.; Aitken, Carolyn M.; Jones, D. Martin; Head, Ian M.; Gray, Neil D.

2014-01-01

Methanogenic degradation of crude oil in subsurface sediments occurs slowly, but without the need for exogenous electron acceptors, is sustained for long periods and has enormous economic and environmental consequences. Here we show that volatile hydrocarbons are inhibitory to methanogenic oil biodegradation by comparing degradation of an artificially weathered crude oil with volatile hydrocarbons removed, with the same oil that was not weathered. Volatile hydrocarbons (nC5–nC10, methylcyclohexane, benzene, toluene, and xylenes) were quantified in the headspace of microcosms. Aliphatic (n-alkanes nC12–nC34) and aromatic hydrocarbons (4-methylbiphenyl, 3-methylbiphenyl, 2-methylnaphthalene, 1-methylnaphthalene) were quantified in the total hydrocarbon fraction extracted from the microcosms. 16S rRNA genes from key microorganisms known to play an important role in methanogenic alkane degradation (Smithella and Methanomicrobiales) were quantified by quantitative PCR. Methane production from degradation of weathered oil in microcosms was rapid (1.1 ± 0.1 μmol CH4/g sediment/day) with stoichiometric yields consistent with degradation of heavier n-alkanes (nC12–nC34). For non-weathered oil, degradation rates in microcosms were significantly lower (0.4 ± 0.3 μmol CH4/g sediment/day). This indicated that volatile hydrocarbons present in the non-weathered oil inhibit, but do not completely halt, methanogenic alkane biodegradation. These findings are significant with respect to rates of biodegradation of crude oils with abundant volatile hydrocarbons in anoxic, sulphate-depleted subsurface environments, such as contaminated marine sediments which have been entrained below the sulfate-reduction zone, as well as crude oil biodegradation in petroleum reservoirs and contaminated aquifers. PMID:24765087

Microbial degradation of crude oil and some model hydrocarbons

USGS Publications Warehouse

Chang, Fu-Hsian; Noben, N.N.; Brand, Danny; Hult, Marc F.

1988-01-01

Research on microbial degradation of crude oil in the shallow subsurface at a spill site near Bemidji, Minn. (fig. C-l), began in 1983 (Hull, 1984; Chang and Ehrlich, 1984). The rate and extent of crude oil and model hydrocarbon biodegradation by the indigenous microbial community was measured in the laboratory at several concentrations of inorganic nutrients, conditions of oxygen availability, incubation temperatures, and incubation time.

Burning crude oil without pollution

NASA Technical Reports Server (NTRS)

Houseman, J.

1979-01-01

Crude oil can be burned at drilling sites by two-stage combustion process without producing pollution. Process allows easier conformance to strict federal or state clean air standards without installation of costly pollution removal equipment. Secondary oil recovery can be accomplished with injection of steam heating by burning oil.

Vacuum Energy and Inflation: 4. An Inflationary Universe

ERIC Educational Resources Information Center

Huggins, Elisha

2013-01-01

This is the fourth paper in a series of four. The first paper in the series, "Vacuum Energy and Inflation: 1. A Liter of Vacuum Energy" [EJ1024183] discusses an example of vacuum energy. Vacuum energy is explained as an energy with a negative pressure whose energy density remains constant in an expanding space. Paper 2, "Vacuum…

Modelling of nectarine drying under near infrared - Vacuum conditions.

PubMed

Alaei, Behnam; Chayjan, Reza Amiri

2015-01-01

Drying of nectarine slices was performed to determine the thermal and physical properties in order to reduce product deterioration due to chemical reactions, facilitate storage and lower transportation costs. Because nectarine slices are sensitive to heat with long drying period, the selection of a suitable drying approach is a challenging task. Infrared-vacuum drying can be used as an appropriate method for susceptible materials with high moisture content such as nectarine slices. Modelling of nectarine slices drying was carried out in a thin layer near infraredvacuum conditions. Drying of the samples was implemented at the absolute pressures of 20, 40 and 60 kPa and drying temperatures of 50, 60 and 70°C. Drying behaviour of nectarine slices, as well as the effect of drying conditions on moisture loss trend, drying rate, effective diffusion coefficient, activation energy, shrinkage, colour and energy consumption of nectarine slices, dried in near infrared-vacuum dryer are discussed in this study. Six mathematical models were used to predict the moisture ratio of the samples in thin layer drying. The Midilli model had supremacy in prediction of nectarine slices drying behaviour. The maximum drying rates of the samples were between 0.014-0.047 gwater/gdry material·min. Effective moisture diffusivity of the samples was estimated in the ranges of 2.46·10-10 to 6.48·10-10 m2/s. Activation energy were computed between 31.28 and 35.23 kJ/mol. Minimum shrinkage (48.4%) and total colour difference (15.1) were achieved at temperature of 50°C and absolute pressure of 20 kPa. Energy consumption of the tests was estimated in the ranges of 0.129 to 0.247 kWh. Effective moisture diffusivity was increased with decrease of vacuum pressure and increase of drying temperature but effect of drying temperature on effective moisture diffusivity of nectarine slices was more than vacuum pressure. Activation energy was decreased with decrease in absolute pressure. Total colour

21 CFR 884.5070 - Vacuum abortion system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...

46 CFR 153.368 - Pressure-vacuum valves.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 5 2014-10-01 2014-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...

46 CFR 153.368 - Pressure-vacuum valves.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 5 2011-10-01 2011-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...

46 CFR 153.368 - Pressure-vacuum valves.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 5 2012-10-01 2012-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...

46 CFR 153.368 - Pressure-vacuum valves.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...

46 CFR 153.368 - Pressure-vacuum valves.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve...

21 CFR 884.5070 - Vacuum abortion system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...

21 CFR 884.5070 - Vacuum abortion system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...

21 CFR 884.5070 - Vacuum abortion system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...

21 CFR 884.5070 - Vacuum abortion system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vacuum abortion system. 884.5070 Section 884.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... § 884.5070 Vacuum abortion system. (a) Identification. A vacuum abortion system is a device designed to...

Very-Low-Cost, Rugged Vacuum System

NASA Technical Reports Server (NTRS)

Kline-Schoder, Robert; Sorensen, Paul; Passow, Christian; Bilski, Steve

2013-01-01

NASA, DoD, DHS, and commercial industry have a need for miniaturized, rugged, low-cost vacuum systems. Recent advances in sensor technology have led to the development of very small mass spectrometer detectors as well as other miniature analytical instruments. However, the vacuum systems to support these sensors remain large, heavy, and power-hungry. To meet this need, a miniaturized vacuum system was created based on a very small, rugged, and inexpensive- to-manufacture molecular drag pump (MDP). The MDP is enabled by the development of a miniature, veryhigh- speed, rugged, low-power, brushless DC motor optimized for wide temperature operation and long life. Such a pump represents an order-of-magnitude reduction in mass, volume, and cost over current, commercially available, state-ofthe- art vacuum pumps. The vacuum system consists of the MDP coupled to a ruggedized rough pump (for terrestrial applications or for planets with substantial atmospheres). The rotor in the MDP consists of a simple smooth cylinder of aluminum spinning at approximately 200,000 RPM inside an outer stator housing. The pump stator comprises a cylindrical aluminum housing with one or more specially designed grooves that serve as flow channels. To minimize the length of the pump, the gas is forced down the flow channels of the outer stator to the base of the pump. The gas is then turned and pulled toward the top through a second set of channels cut into an inner stator housing that surrounds the motor. The compressed gas then flows down channels in the motor housing to the exhaust port of the pump. The exhaust port of the pump is connected to a diaphragm or scroll pump. This pump delivers very high performance in a very small envelope. The design was simplified so that a smaller compression ratio, easier manufacturing process, and enhanced ruggedness can be achieved at the lowest possible cost. The machining of the rotor and stators is very simple compared to that necessary to fabricate TMP

The localized quantum vacuum field

NASA Astrophysics Data System (ADS)

Dragoman, D.

2008-03-01

A model for the localized quantum vacuum is proposed in which the zero-point energy (ZPE) of the quantum electromagnetic field originates in energy- and momentum-conserving transitions of material systems from their ground state to an unstable state with negative energy. These transitions are accompanied by emissions and re-absorptions of real photons, which generate a localized quantum vacuum in the neighborhood of material systems. The model could help resolve the cosmological paradox associated with the ZPE of electromagnetic fields, while reclaiming quantum effects associated with quantum vacuum such as the Casimir effect and the Lamb shift. It also offers a new insight into the Zitterbewegung of material particles.

Dispersion of Louisiana crude oil in salt water environment by Corexit 9500A in the presence of natural coastal materials

NASA Astrophysics Data System (ADS)

Tansel, Berrin; Lee, Mengshan; Berbakov, Jillian; Tansel, Derya Z.; Koklonis, Urpiana

2014-04-01

Effectiveness of Corexit 9500A for dispersing Louisiana crude oil was evaluated in salt water solutions containing natural materials in relation to salinity and dispersant-to-oil ratio (DOR). Experimental results showed that both salinity and DOR had significant effects on dispersion of Louisiana crude oil in the presence of different natural materials. The natural materials added to the salt water solutions included sea sand (South Beach, Miami, Florida), red mangrove leaves (Rhizophora mangle), seaweed (Sargassum natans), and sea grass (Halodule wrightii). Dispersant effectiveness (amount of oil dispersed into the water) was reduced significantly with increasing salinity with the minimum effectiveness observed in the salinity range between 30 and 50 ppt in all aqueous samples containing natural materials. When significant amounts of floating oil were present, the partially submerged natural materials enhanced the transfer of oil into the water column, which improved the dispersion effectiveness. However, dispersant effectiveness was significantly reduced when the amount of floating oil was relatively small and could not be released back to the water column. Surface tension may not be an adequate parameter for monitoring the effectiveness of dispersants in salt water environment. When distilled water was used (i.e., zero salinity), surface tension was significantly reduced with increasing dispersant concentration. However, there was no clear trend in the surface tension of the salt water solutions (17-51 ppt) containing crude oil and natural materials with increasing dispersant concentration.

Vacuum casting of thick polymeric films

NASA Technical Reports Server (NTRS)

Cuddihy, E. F.; Moacanin, J.

1979-01-01

Bubble formation and layering, which often plague vacuum-evaporated films, are prevented by properly regulating process parameters. Vacuum casting may be applicable to forming thick films of other polymer/solvent solutions.

14 CFR 25.1433 - Vacuum systems.

Code of Federal Regulations, 2010 CFR

2010-01-01

... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe. [Doc. No...

Ceramic vacuum tubes for geothermal well logging

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

Kelly, R.D.

1977-01-12

The results of investigations carried out into the availability and suitability of ceramic vacuum tubes for the development of logging tools for geothermal wells are summarized. Design data acquired in the evaluation of ceramic vacuum tubes for the development of a 500/sup 0/C instrumentation amplifier are presented. The general requirements for ceramic vacuum tubes for application to the development of high temperature well logs are discussed. Commercially available tubes are described and future contract activities that specifically relate to ceramic vacuum tubes are detailed. Supplemental data is presented in the appendix. (MHR)

Effect of surfactants on dielectric strength of crude oil

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

Yunusov, A.A.

1995-09-01

In all the methods used for crude oil demulsification, including electrodemulsification, surfactants are used to aid the demulsification. Therefore, the present work has been aimed at studying the character and degree of influence of surfactants on the dielectric strength of crude oil. Our experiments were performed with a standard discharger at an AC frequency of 50 Hz. The high-voltage source was a universal breakdown unit of the UPU-1 type.

Compressed Air/Vacuum Transportation Techniques

NASA Astrophysics Data System (ADS)

Guha, Shyamal

2011-03-01

General theory of compressed air/vacuum transportation will be presented. In this transportation, a vehicle (such as an automobile or a rail car) is powered either by compressed air or by air at near vacuum pressure. Four version of such transportation is feasible. In all versions, a ``c-shaped'' plastic or ceramic pipe lies buried a few inches under the ground surface. This pipe carries compressed air or air at near vacuum pressure. In type I transportation, a vehicle draws compressed air (or vacuum) from this buried pipe. Using turbine or reciprocating air cylinder, mechanical power is generated from compressed air (or from vacuum). This mechanical power transferred to the wheels of an automobile (or a rail car) drives the vehicle. In type II-IV transportation techniques, a horizontal force is generated inside the plastic (or ceramic) pipe. A set of vertical and horizontal steel bars is used to transmit this force to the automobile on the road (or to a rail car on rail track). The proposed transportation system has following merits: virtually accident free; highly energy efficient; pollution free and it will not contribute to carbon dioxide emission. Some developmental work on this transportation will be needed before it can be used by the traveling public. The entire transportation system could be computer controlled.

Vacuum chamber-free centrifuge with magnetic bearings.

PubMed

Park, Cheol Hoon; Kim, Soohyun; Kim, Kyung-Soo

2013-09-01

Centrifuges are devices that separate particles of different densities and sizes through the application of a centrifugal force. If a centrifuge could be operated under atmospheric conditions, all vacuum-related components such as the vacuum chamber, vacuum pump, diffusion pump, and sealing could be removed from a conventional centrifuge system. The design and manufacturing procedure for centrifuges could then be greatly simplified to facilitate the production of lightweight centrifuge systems of smaller volume. Furthermore, the maintenance costs incurred owing to wear and tear due to conventional ball bearings would be eliminated. In this study, we describe a novel vacuum chamber-free centrifuge supported by magnetic bearings. We demonstrate the feasibility of the vacuum chamber-free centrifuge by presenting experimental results that verify its high-speed support capability and motoring power capacity.

Cryogenic Insulation System for Soft Vacuum

NASA Technical Reports Server (NTRS)

Augustynowicz, S. D.; Fesmire, J. E.

1999-01-01

The development of a cryogenic insulation system for operation under soft vacuum is presented in this paper. Conventional insulation materials for cryogenic applications can be divided into three levels of thermal performance, in terms of apparent thermal conductivity [k-value in milliwatt per meter-kelvin (mW/m-K)]. System k-values below 0.1 can be achieved for multilayer insulation operating at a vacuum level below 1 x 10(exp -4) torr. For fiberglass or powder operating below 1 x 10(exp -3) torr, k-values of about 2 are obtained. For foam and other materials at ambient pressure, k-values around 30 are typical. New industry and aerospace applications require a versatile, robust, low-cost thermal insulation with performance in the intermediate range. The target for the new composite insulation system is a k-value below 4.8 mW/m-K (R-30) at a soft vacuum level (from 1 to 10 torr) and boundary temperatures of approximately 77 and 293 kelvin (K). Many combinations of radiation shields, spacers, and composite materials were tested from high vacuum to ambient pressure using cryostat boiloff methods. Significant improvement over conventional systems in the soft vacuum range was demonstrated. The new layered composite insulation system was also shown to provide key benefits for high vacuum applications as well.

Pectinesterase inhibitor from jelly-fig (Ficus awkeotsang Makino) achenes reduces methanol content in carambola wine.

PubMed

Wu, James Swi-Bea; Wu, Ming-Chang; Jiang, Chii-Ming; Hwang, Ya-Ping; Shen, Szu-Chuan; Chang, Hung-Min

2005-11-30

Crude pectinesterase (PE) inhibitor (PEI) extracted from jelly-fig achenes (JFA) (Ficus awakeosang Makino) was added to carambola (Averrhoa carambola L.) puree to determine the change in methanol production during fermentation. Addition of pectin or microbial pectic enzyme to puree increased dose-dependently the methanol content in fermented products. Decreasing ratio (from 1:0 to 1:19, v:v) of pectic enzyme to diluted crude PEI solution in the puree-enzyme mixture decreased the PE activity remarkably. Except for transmittance (%T), addition of crude PEI to puree did not affect apparently the physical and chemical properties of wine; however, it reduced methanol content in the control from 256 to 58 ppm. The degree of esterification (DE) of pectin in starting puree was approximately 70%. It decreased to approximately 27% in the control group and reduced slightly to approximately 67% in fermented puree with crude PEI added after 14 days of fermentation. This reveals that crude PEI solution was potent in inhibiting intrinsic carambola PE activity and appeared to be a potential alternative for methanol reduction in wines.

33 CFR 157.172 - Limitations on grades of crude oil carried.

Code of Federal Regulations, 2010 CFR

2010-07-01

... VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Cow Operations § 157.172 Limitations on grades of crude oil carried. If a tank vessel having a COW system meeting § 157.10a(a)(2) or...

Crude oil metabolites in groundwater at two spill sites

USGS Publications Warehouse

Bekins, Barbara A.; Cozzarelli, Isabelle M.; Erickson, Melinda L.; Steenson, Ross; Thorn, Kevin A.

2016-01-01

Two groundwater plumes in north central Minnesota with residual crude oil sources have 20 to 50 mg/L of nonvolatile dissolved organic carbon (NVDOC). These values are over 10 times higher than benzene and two to three times higher than Diesel Range Organics in the same wells. On the basis of previous work, most of the NVDOC consists of partial transformation products from the crude oil. Monitoring data from 1988 to 2015 at one of the sites located near Bemidji, MN show that the plume of metabolites is expanding toward a lakeshore located 335 m from the source zone. Other mass balance studies of the site have demonstrated that the plume expansion is driven by the combined effect of continued presence of the residual crude oil source and depletion of the electron accepting capacity of solid phase iron oxide and hydroxides on the aquifer sediments. These plumes of metabolites are not covered by regulatory monitoring and reporting requirements in Minnesota and other states. Yet, a review of toxicology studies indicates that polar metabolites of crude oil may pose a risk to aquatic and mammalian species. Together the results suggest that at sites where residual sources are present, monitoring of NVDOC may be warranted to evaluate the fates of plumes of hydrocarbon transformation products.

Breakthrough Adsorption Study of Crude Oil Removal Using Buffing Dust

NASA Astrophysics Data System (ADS)

Setyaningsih, L. W. N.; Yuliansyah, A. T.; Prasetyo, A.; Arimanintan, S. K.; Putri, D. R.

2018-05-01

The utilization of leather industry solid waste as adsorbent to separate oil from water emulsions of surfactant flooding process is a solution that is relatively inexpensive. This study was conducted aiming to obtain a mathematical model that is appropriate for the adsorption process of crude oil by buffing dust in emulsion phase with a continuous adsorption method. Variations in the column adsorption experiments were carried out, such as: flow rate of feed of water-crude oil-surfactant, the concentration of crude oil in the feed, and mass of adsorbent used. Data were evaluated using three models: Adams Bohart, Thomas and Yan. Best results are obtained on the following conditions, the feed flow rate of 60 mL/minute, the crude oil concentration in feed is 1.5% volume and the mass of adsorbent used was 10 g. The values of kinetic constant and adsorption capacity obtained from Yan Model was 21.7774 mL/mg/minute and 220.9581 mg/g with the relative error obtained is 5.4424%.

Effect of a commercial steam-vacuuming treatment implemented after slaughtering for the decontamination of cattle carcasses

PubMed Central

Hochreutener, Mirjam; Zweifel, Claudio; Corti, Sabrina; Stephan, Roger

2017-01-01

To assess the antimicrobial effect of a commercial steam-vacuuming system newly implemented after slaughtering, 105 cattle carcasses were examined for total viable counts (TVC) at four different areas. Before steam vacuuming, mean TVC of the excision samples were comparable at the perineal area and brisket (3.0-3.1 log CFU cm-2) or the hind leg and shoulder (2.6-2.7 log CFU cm-2). Steam vacuuming reduced mean TVC by 0.9, 0.7, 0.6, and 0.4 log CFU cm-2 at the perineal area, hind leg, shoulder, and brisket, respectively. With regard to the distribution of counts, steam vacuuming increased the proportion of TVC results <3.0 log CFU cm-2 from 74.8% (62.9-87.6% at carcass areas) to 86.7% (71.4-97.1% at carcass areas). Thus, steam vacuuming after slaughtering might be useful for the reduction of contamination in designated carcass areas, but the effect must not be overestimated and decontamination treatments always must be seen part of an integral food safety system. PMID:29071245

Purifying Aluminum by Vacuum Distillation

NASA Technical Reports Server (NTRS)

Du Fresne, E. R.

1985-01-01

Proposed method for purifying aluminum employs one-step vacuum distillation. Raw material for process impure aluminum produced in electrolysis of aluminum ore. Impure metal melted in vacuum. Since aluminum has much higher vapor pressure than other constituents, boils off and condenses on nearby cold surfaces in proportions much greater than those of other constituents.

Crude oil contaminated soil washing in air sparging assisted stirred tank reactor using biosurfactants.

PubMed

Urum, Kingsley; Pekdemir, Turgay; Ross, David; Grigson, Steve

2005-07-01

This study investigated the removal of crude oil from soil using air sparging assisted stirred tank reactors. Two surfactants (rhamnolipid and sodium dodecyl sulfate, SDS) were tested and the effects of different parameters (i.e. temperature, surfactant concentrations, washing time, volume/mass ratio) were investigated under varying washing modes namely, stirring only, air sparging only and the combination of stirring and air sparging. The results showed that SDS removed more than 80% crude oil from non-weathered soil samples, whilst rhamnolipid showed similar oil removal at the third and fourth levels of the parameters tested. The oil removal ability of the seawater prepared solutions were better than those of the distilled water solutions at the first and second levels of temperature and concentration of surfactant solutions. This approach of soil washing was noted to be effective in reducing the amount of oil in soil. Therefore we suggested that a field scale test be conducted to assess the efficiency of these surfactants.

Breakdown-Resistant RF Connectors for Vacuum

NASA Technical Reports Server (NTRS)

Caro, Edward R.; Bonazza, Walter J.

1987-01-01

Resilient inserts compensate for insulation shrinkage. Coaxial-cable connector for radio-frequency (RF) energy resists electrical breakdown in vacuum. Used on RF equipment in vacuum chambers as well as in spaceborne radar and communication gear.

Tanker spills Norwegian crude oil off Shetlands

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

Not Available

1993-01-11

This paper reports that crude oil was spilling last week from the U.S. owned Braer tanker after the 89,000 dwt vessel ran aground on the south end of Scotland's Shetland Islands. Workers were trying to assess the extent of damage to the tanker, shoreline, and wildlife after the January 5 accident. Braer's cargo amounted to 607,000 bbl of Norwegian oil bound for Canada. Braer loaded its cargo and sailed January 3 from Den norske stats oljeselskap AS's Mongstad, Norway, terminal with crude from Gullfaks field in the Norwegian North Sea. The $11 million shipment was destined for Ultramar Canada Inc.'smore » 125,000 b/d refinery at St. Romuald, Que.« less

Breather cloth for vacuum curing

NASA Technical Reports Server (NTRS)

Reed, M. W.

1979-01-01

Finely-woven nylon cloth that has been treated with Teflon improves vacuum adhesive bonding of coatings to substrates. Cloth is placed over coating; entire assembly, including substrate, coating, and cloth, is placed in plastic vacuum bag for curing. Cloth allows coating to "breathe" when bag is evacuated. Applications include bonding film coatings to solar concentrators and collectors.

Vacuum Gas Tungsten Arc Welding

NASA Technical Reports Server (NTRS)

Weeks, J. L.; Todd, D. T.; Wooten, J. R.

1997-01-01

A two-year program investigated vacuum gas tungsten arc welding (VGTAW) as a method to modify or improve the weldability of normally difficult-to-weld materials. After a vacuum chamber and GTAW power supply were modified, several difficult-to-weld materials were studied and key parameters developed. Finally, Incoloy 903 weld overlays were produced without microfissures.

Self-Lubricating, Wear-Resistant Diamond Films Developed for Use in Vacuum Environment

NASA Technical Reports Server (NTRS)

1996-01-01

Diamond's outstanding properties--extreme hardness, chemical and thermal inertness, and high strength and rigidity--make it an ideal material for many tribological applications, such as the bearings, valves, and engine parts in the harsh environment found in internal-combustion engines, jet engines, and space propulsion systems. It has been demonstrated that chemical-vapor-deposited diamond films have low coefficients of friction (on the order of 0.01) and low wear rates (less than 10(sup -7) mm (sup 3/N-m)) both in humid air and dry nitrogen but that they have both high coefficients of friction (greater than 0.4) and high wear rates (on the order of 1(sup -4) mm sup 3/N-m)) in vacuum. It is clear that surface modifications that provide acceptable levels of friction and wear properties will be necessary before diamond films can be used for tribological applications in a space-like, vacuum environment. Previously, it was found that coatings of amorphous, non-diamond carbon can provide low friction in vacuum. Therefore, to reduce the friction and wear of diamond film in vacuum, carbon ions were implanted in an attempt to form a surface layer of amorphous carbon phases on the diamond films.

TFTR diagnostic vacuum controller

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

Olsen, D.; Persons, R.

1981-01-01

The TFTR diagnostic vacuum controller (DVC) provides in conjunction with the Central Instrumentation Control and Data Acquisition System (CICADA), control and monitoring for the pumps, valves and gauges associated with each individual diagnostic vacuum system. There will be approximately 50 systems on TFTR. Two standard versions of the controller (A and B) wil be provided in order to meet the requirements of two diagnostic manifold arrangements. All pump and valve sequencing, as well as protection features, will be implemented by the controller.

Evaluation of the ability of Eleutherine americana crude extract as natural food additive in cooked pork.

PubMed

Ifesan, B O T; Siripongvutikorn, S; Hutadilok-Towatana, N; Voravuthikunchai, S P

2009-09-01

The scavenging activities of crude ethanolic extract from Eleutherine americana, on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl free radicals were investigated. The results revealed that the extract produced IC(50) values of 8.4 microg/mL and 0.78 mg/mL on DPPH and hydroxyl free radicals, respectively. The total phenolic content of the extract was determined using the Folin-Ciocalteu reagent and the crude extract yielded high phenolic content of 4.56 mumol gallic acid equivalent per milligram dried extract. The extract, at different concentrations, was incorporated into pork, cooked in the microwave, and stored at 4 degrees C for 9 d. The crude extract demonstrated antioxidant activity, which increases with increased extract concentrations and retarded lipid oxidation in the cooked pork. Antibacterial activity of the extract against Staphylococcus aureus in the cooked pork revealed that at a concentration of 10.8 mg/100 g, the extract reduced the bacterial population by 0.57 log compared to control at 9 d of storage. The sensory results revealed that the pork samples treated with the extract and the control sample were not significantly different from day 0 to 6; however, on day 9 the treatments were significantly scored higher than the control. Furthermore, addition of the extract led to an increase in the redness values of the pork and this was acceptable from the sensory point of view. E. americana crude extract could be a promising novel antioxidant to prevent lipid oxidation and a potential natural color enhancer of red meat and meat products.

Vacuum polarization of the electromagnetic field near a rotating black hole

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

Frolov, V.P.; Zel'nikov, A.I.

1985-12-15

The electromagnetic field contribution to the vacuum polarization near a rotating black hole is considered. It is shown that the problem of calculating the renormalized average value of the stress-energy tensor /sup ren/ for the Hartle-Hawking vacuum state at the pole of the event horizon can be reduced to the problem of electro- and magnetostatics in the Kerr spacetime. An explicit expression for /sup ren/ at the pole of the event horizon is obtained and its properties are discussed. It is shown that in the case of a nonrotating black hole the Page-Brown approximation for the electromagnetic stress-energy tensor givesmore » a result which coincides at the event horizon with the exact value of /sup ren/. .AE« less

Impact of formation water geochemistry and crude oil biodegradation on microbial methanogenesis

USGS Publications Warehouse

Shelton, Jenna L.; McIntosh, Jennifer C.; Warwick, Peter D.; McCray, John E.

2016-01-01

Shallow wells (393–442 m depth) contained highly biodegraded oils associated with low extent of methanogenesis, while the deepest (> 1208 m) wells contained minimally degraded oils and produced fluids suggesting a low extent of methanogenesis. Mid-depth wells (666–857 m) in the central field had the highest indicators of methanogenesis and contained moderately biodegraded oils. Little correlation existed between extents of crude oil biodegradation and methanogenesis across the whole transect (avg.R2 = 0.13). However, when wells with the greatest extent of crude oil biodegradation were eliminated (3 of 6 oilfields), better correlation between extent of methanogenesis and biodegradation (avg. R2 = 0.53) was observed. The results suggest that oil quality and salinity impact methanogenic crude oil biodegradation. Reservoirs indicating moderate extent of crude oil biodegradation and high extent of methanogenesis, such as the central field, would be good candidates for attempting to enhance methanogenic crude oil biodegradation as a result of the observations from the study.

Fate of electroweak vacuum during preheating

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

Ema, Yohei; Mukaida, Kyohei; Nakayama, Kazunori

2016-10-28

Our electroweak vacuum may be metastable in light of the current experimental data of the Higgs/top quark mass. If this is really the case, high-scale inflation models require a stabilization mechanism of our vacuum during inflation. A possible candidate is the Higgs-inflaton/-curvature coupling because it induces an additional mass term to the Higgs during the slow roll regime. However, after inflation, the additional mass term oscillates, and it can destabilize our electroweak vacuum via production of large Higgs fluctuations during the inflaton oscillation era. In this paper, we study whether or not the Higgs-inflaton/-curvature coupling can save our vacuum bymore » properly taking account of Higgs production during the preheating stage. We put upper bounds on the Higgs-inflaton and -curvature couplings, and discuss possible dynamics that might relax them.« less

Pelagia noctiluca (Scyphozoa) Crude Venom Injection Elicits Oxidative Stress and Inflammatory Response in Rats

PubMed Central

Bruschetta, Giuseppe; Impellizzeri, Daniela; Morabito, Rossana; Marino, Angela; Ahmad, Akbar; Spanò, Nunziacarla; La Spada, Giuseppa; Cuzzocrea, Salvatore; Esposito, Emanuela

2014-01-01

Cnidarian toxins represent a rich source of biologically active compounds. Since they may act via oxidative stress events, the aim of the present study was to verify whether crude venom, extracted from the jellyfish Pelagia noctiluca, elicits inflammation and oxidative stress processes, known to be mediated by Reactive Oxygen Species (ROS) production, in rats. In a first set of experiments, the animals were injected with crude venom (at three different doses 6, 30 and 60 µg/kg, suspended in saline solution, i.v.) to test the mortality and possible blood pressure changes. In a second set of experiments, to confirm that Pelagia noctiluca crude venom enhances ROS formation and may contribute to the pathophysiology of inflammation, crude venom-injected animals (30 µg/kg) were also treated with tempol, a powerful antioxidant (100 mg/kg i.p., 30 and 60 min after crude venom). Administration of tempol after crude venom challenge, caused a significant reduction of each parameter related to inflammation. The potential effect of Pelagia noctiluca crude venom in the systemic inflammation process has been here demonstrated, adding novel information about its biological activity. PMID:24727391

Development of Electromagnetically Actuated Vacuum Circuit Breaker for 72kV Rated Switchgear

NASA Astrophysics Data System (ADS)

Kim, Tae-Hyun; Tsukima, Mitsuru; Maruyama, Akihiko; Takahara, Osamu; Haruna, Kazushi; Yano, Tomotaka; Matsunaga, Toshihiro; Imamura, Kazuaki; Arioka, Masahiro; Takeuchi, Toshie

A new electromagnetically actuated vacuum circuit breaker (VCB) has been developed for a 72kV rated switchgear. Each phase of this VCB has a plurality of compact electromagnetic actuators linked mechanically providing the required driving energy. The mechanical linkage working as a lever magnifies an actuator stroke to the required stroke of a 72kV rated vacuum interrupter. An electromagnetic analysis coupled with motion, which considers the mechanical linkage of the plural actuators, has been developed for designing the driving behavior of this VCB. Using this analytical method and a quality engineering method known as the Taguchi method, we have clarified effective parameters to reduce the time difference of the driving behavior for tolerance specifications. Moreover, analyzing the oscillatory behavior closing the contacts, a structure of this VCB has been designed to reduce the bounce duration. The developed new VCB has been confirmed that a time difference is short enough and bounce duration is reduced. This VCB is highly reliable against variations in manufacturing and environment.

Physico-chemical characterization of products from vacuum oil under delayed coking process by infrared spectroscopy and chemometrics methods

NASA Astrophysics Data System (ADS)

Meléndez, L. V.; Cabanzo, R.; Mejía-Ospino, E.; Guzmán, A.

2016-02-01

Eight vacuum residues and their delayed coking liquids products from Colombian crude were study by infrared spectroscopy with attenuated total reflectance (FTIR-ATR) and principal component analysis (PCA). For the samples the structural parameters of aromaticity factor (fa), alifaticity (A2500-3100cm-1), aromatic condensation degree (GCA), length of aliphatic chains (LCA) and aliphatic chain length associated with aromatic (LACAR) were determined through the development of a methodology, which includes the previous processing of spectroscopy data, identifying the regions in the IR spectra of greatest variance using PCA and molecules patterns. The parameters were compared with the results obtained from proton magnetic resonance (1H-NMR) and 13C-NMR. The results showed the influence and correlation of structural parameters with some physicochemical properties such as API gravity, weight percent sulphur (% S) and Conradson carbon content (% CCR)

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

NASA Technical Reports Server (NTRS)

Dever, Joyce A.; Degroh, Kim K.; Stidham, Curtis R.; Stueber, Thomas J.; Dever, Therese M.; Rodriguez, Elvin; Terlep, Judith A.

1992-01-01

In order to assess the low Earth orbit (LEO) durability of candidate space materials, it is necessary to use ground laboratory facilities which provide LEO environmental effects. A facility combining vacuum thermal cycling and vacuum ultraviolet (VUV) radiation has been designed and constructed at NASA Lewis Research Center for this purpose. This facility can also be operated without the VUV lamps. An additional facility can be used to provide VUV exposure only. By utilizing these facilities, followed by atomic oxygen exposure in an RF plasma asher, the effects of the individual vacuum thermal cycling and VUV environments can be compared to the effect of the combined vacuum thermal cycling/VUV environment on the atomic oxygen durability of materials. The synergistic effects of simulated LEO environmental conditions on materials were evaluated by first exposing materials to vacuum thermal cycling, VUV, and vacuum thermal cycling/VUV environments followed by exposure to atomic oxygen in an RP plasma asher. Candidate space power materials such as atomic oxygen protected polyimides and solar concentrator mirrors were evaluated using these facilities. Characteristics of the Vacuum Thermal Cycling/VUV Exposure Facility which simulates the temperature sequences and solar ultraviolet radiation exposure that would be experienced by a spacecraft surface in LEO are discussed. Results of durability evaluations of some candidate space power materials to the simulated LEO environmental conditions will also be discussed. Such results have indicated that for some materials, atomic oxygen durability is affected by previous exposure to thermal cycling and/or VUV exposure.

Compact vacuum insulation

DOEpatents

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

1993-01-05

An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially point'' or line'' contacts with the metal wall sheets. In the case of monolithic spacers that form line'' contacts, two such spacers with the line contacts running perpendicular to each other form effectively point'' contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

Compact vacuum insulation

DOEpatents

Benson, David K.; Potter, Thomas F.

1993-01-01

An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially "point" or "line" contacts with the metal wall sheets. In the case of monolithic spacers that form "line" contacts, two such spacers with the line contacts running perpendicular to each other form effectively "point" contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

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

PubMed

Winter, S; Smith, A; Lappin, D; McDonagh, G; Kirk, B

2017-12-01

Dental handpieces are required to be sterilized between patient use. Vacuum steam sterilization processes with fractionated pre/post-vacuum phases or unique cycles for specified medical devices are required for hollow instruments with internal lumens to assure successful air removal. Entrapped air will compromise achievement of required sterilization conditions. Many countries and professional organizations still advocate non-vacuum sterilization processes for these devices. To investigate non-vacuum downward/gravity displacement, type-N steam sterilization of dental handpieces, using thermometric methods to measure time to achieve sterilization temperature at different handpiece locations. Measurements at different positions within air turbines were undertaken with thermocouples and data loggers. Two examples of widely used UK benchtop steam sterilizers were tested: a non-vacuum benchtop sterilizer (Little Sister 3; Eschmann, Lancing, UK) and a vacuum benchtop sterilizer (Lisa; W&H, Bürmoos, Austria). Each sterilizer cycle was completed with three handpieces and each cycle in triplicate. A total of 140 measurements inside dental handpiece lumens were recorded. The non-vacuum process failed (time range: 0-150 s) to reliably achieve sterilization temperatures within the time limit specified by the international standard (15 s equilibration time). The measurement point at the base of the handpiece failed in all test runs (N = 9) to meet the standard. No failures were detected with the vacuum steam sterilization type B process with fractionated pre-vacuum and post-vacuum phases. Non-vacuum downward/gravity displacement, type-N steam sterilization processes are unreliable in achieving sterilization conditions inside dental handpieces, and the base of the handpiece is the site most likely to fail. Copyright © 2017 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Anti-Quorum Sensing Potential of Crude Kigelia africana Fruit Extracts

PubMed Central

Chenia, Hafizah Y.

2013-01-01

The increasing incidence of multidrug-resistant pathogens has stimulated the search for novel anti-virulence compounds. Although many phytochemicals show promising antimicrobial activity, their power lies in their anti-virulence properties. Thus the quorum sensing (QS) inhibitory activity of four crude Kigelia africana fruit extracts was assessed qualitatively and quantitatively using the Chromobacterium violaceum and Agrobacterium tumefaciens biosensor systems. Inhibition of QS-controlled violacein production in C. violaceum was assayed using the qualitative agar diffusion assay as well as by quantifying violacein inhibition using K. africana extracts ranging from 0.31–8.2 mg/mL. Qualitative modulation of QS activity was investigated using the agar diffusion double ring assay. All four extracts showed varying levels of anti-QS activity with zones of violacein inhibition ranging from 9–10 mm. The effect on violacein inhibition was significant in the following order: hexane > dichloromethane > ethyl acetate > methanol. Inhibition was concentration-dependent, with the ≥90% inhibition being obtained with ≥1.3 mg/mL of the hexane extract. Both LuxI and LuxR activity were affected by crude extracts suggesting that the phytochemicals target both QS signal and receptor. K. africana extracts with their anti-QS activity, have the potential to be novel therapeutic agents, which might be important in reducing virulence and pathogenicity of drug-resistant bacteria in vivo. PMID:23447012

Study on convection improvement of standard vacuum tube

NASA Astrophysics Data System (ADS)

He, J. H.; Du, W. P.; Qi, R. R.; He, J. X.

2017-11-01

For the standard all-glass vacuum tube collector, enhancing the vacuum tube axial natural convection can improve its thermal efficiency. According to the study of the standard all-glass vacuum tube, three kinds of guide plates which can inhibit the radial convection and increase axial natural convection are designed, and theory model is established. Experiments were carried out on vacuum tubes with three types of baffles and standard vacuum tubes without the improvement. The results show that T-type guide plate is better than that of Y-type guide plate on restraining convection and increasing axial radial convection effect, Y type is better than that of flat plate type, all guide plates are better than no change; the thermal efficiency of the tube was 2.6% higher than that of the unmodified standard vacuum tube. The efficiency of the system in the experiment can be increased by 3.1%.

21 CFR 864.9125 - Vacuum-assisted blood collection system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...

21 CFR 864.9125 - Vacuum-assisted blood collection system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...

21 CFR 864.9125 - Vacuum-assisted blood collection system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...

21 CFR 864.9125 - Vacuum-assisted blood collection system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...

21 CFR 864.9125 - Vacuum-assisted blood collection system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vacuum-assisted blood collection system. 864.9125... Blood and Blood Products § 864.9125 Vacuum-assisted blood collection system. (a) Identification. A vacuum-assisted blood collection system is a device intended for medical purposes that uses a vacuum to...

Brazilian sugarcane ethanol as an expandable green alternative to crude oil use

NASA Astrophysics Data System (ADS)

Jaiswal, Deepak; de Souza, Amanda P.; Larsen, Søren; Lebauer, David S.; Miguez, Fernando E.; Sparovek, Gerd; Bollero, Germán; Buckeridge, Marcos S.; Long, Stephen P.

2017-11-01

Reduction of CO2 emissions will require a transition from fossil fuels to alternative energy sources. Expansion of Brazilian sugarcane ethanol provides one near-term scalable solution to reduce CO2 emissions from the global transport sector. In contrast to corn ethanol, the Brazilian sugarcane ethanol system may offset 86% of CO2 emissions compared to oil use, and emissions resulting from land-use change to sugarcane are paid back in just 2-8 years. But, it has been uncertain how much further expansion is possible given increasing demand for food and animal feed, climate change impacts and protection of natural ecosystems. We show that Brazilian sugarcane ethanol can provide the equivalent of 3.63-12.77 Mb d-1 of crude oil by 2045 under projected climate change while protecting forests under conservation and accounting for future land demand for food and animal feed production. The corresponding range of CO2 offsets is 0.55-2.0 Gigatons yr-1. This would displace 3.8-13.7% of crude oil consumption and 1.5-5.6% of net CO2 emission globally relative to data for 2014.

Testing the weak-form efficiency of the WTI crude oil futures market

NASA Astrophysics Data System (ADS)

Jiang, Zhi-Qiang; Xie, Wen-Jie; Zhou, Wei-Xing

2014-07-01

The weak-form efficiency of energy futures markets has long been studied and empirical evidence suggests controversial conclusions. In this work, nonparametric methods are adopted to estimate the Hurst indexes of the WTI crude oil futures prices (1983-2012) and a strict statistical test in the spirit of bootstrapping is put forward to verify the weak-form market efficiency hypothesis. The results show that the crude oil futures market is efficient when the whole period is considered. When the whole series is divided into three sub-series separated by the outbreaks of the Gulf War and the Iraq War, it is found that the Gulf War reduced the efficiency of the market. If the sample is split into two sub-series based on the signing date of the North American Free Trade Agreement, the market is found to be inefficient in the sub-periods during which the Gulf War broke out. The same analysis on short-time series in moving windows shows that the market is inefficient only when some turbulent events occur, such as the oil price crash in 1985, the Gulf war, and the oil price crash in 2008.

Biosurfactant-assisted bioremediation of crude oil by indigenous bacteria isolated from Taean beach sediment.

PubMed

Lee, Dong Wan; Lee, Hanbyul; Kwon, Bong-Oh; Khim, Jong Seong; Yim, Un Hyuk; Kim, Beom Seok; Kim, Jae-Jin

2018-05-25

Crude oil and its derivatives are considered as one group of the most pervasive environmental pollutants in marine environments. Bioremediation using oil-degrading bacteria has emerged as a promising green cleanup alternative in more recent years. The employment of biosurfactant-producing and hydrocarbon-utilizing indigenous bacteria enhances the effectiveness of bioremediation by making hydrocarbons bioavailable for degradation. In this study, the best candidates of biosurfactant-producing indigenous bacteria were selected by screening of biochemical tests. The selected bacteria include Bacillus algicola (003-Phe1), Rhodococcus soli (102-Na5), Isoptericola chiayiensis (103-Na4), and Pseudoalteromonas agarivorans (SDRB-Py1). In general, these isolated species caused low surface tension values (33.9-41.3 mN m -1 ), high oil spreading (1.2-2.4 cm), and hydrocarbon emulsification (up to 65%) warranting active degradation of hydrocarbons. FT-IR and LC-MS analyses indicated that the monorhamnolipid (Rha-C 16:1 ) and dirhamnolipid (Rha-Rha-C 6 -C 6:1 ) were commonly produced by the bacteria as potent biosurfactants. The residual crude oil after the biodegradation test was quantitated using GC-MS analysis. The bacteria utilized crude oil as their sole carbon source while the amount of residual crude oil significantly decreased. In addition the cell-free broth containing biosurfactants produced by bacterial strains significantly desorbed crude oil in oil-polluted marine sediment. The selected bacteria might hold additional capacity in crude oil degradation. Biosurfactant-producing indigenous bacteria therefore degrade crude oil hydrocarbon compounds, produce biosurfactants that can increase the emulsification of crude oil and are thus more conducive to the degradation of crude oil. Copyright © 2018 Elsevier Ltd. All rights reserved.

Seahorse (Hippocampus reidi) as a bioindicator of crude oil exposure.

PubMed

Delunardo, Frederico Augusto Cariello; de Carvalho, Luciano Rodrigues; da Silva, Bruno Ferreira; Galão, Michel; Val, Adalberto Luís; Chippari-Gomes, Adriana R

2015-07-01

This study explored the suitability of the seahorse Hippocampus reidi (Ginsburg, 1933) for assessing biomarkers of genotoxic effects and its use as a sentinel organism to detect the effects of acute exposure to petroleum hydrocarbons. Fish were exposed to three concentrations of crude oil (10, 20 and 30 g/kg) for 96 h, and the activity of phase II biotransformation enzyme glutathione S-transferase (GST) was measured. In addition, we performed genotoxicity assays, such as comet assay, micronucleus (MN) test and nuclear abnormalities (NA) induction, on the erythrocytes of the fish species. Our results revealed that the inhibition of hepatic GST activity in H. reidi was dependent on increasing crude oil concentrations. In contrast, an increase in the damage index (DI) and MN frequency were observed with increased crude oil concentrations. These results indicate that the alkaline comet assay and micronucleus test were suitable and useful in the evaluation of the genotoxicity of crude oil, which could improve determinations of the impact of oil spills on fish populations. In addition, H. reidi is a promising "sentinel organism" to detect the genotoxic impact of petroleum hydrocarbons. Copyright © 2015 Elsevier Inc. All rights reserved.

Method for treating reactive metals in a vacuum furnace

DOEpatents

Hulsey, W.J.

1975-10-28

The invention is directed to a method for reducing the contamination of reactive metal melts in vacuum furnaces due to the presence of residual gaseous contaminants in the furnace atmosphere. This reduction is achieved by injecting a stream of inert gas directly over the metal confined in a substantially closed crucible with the flow of the gas being sufficient to establish a pressure differential between the interior of the crucible and the furnace atmosphere.

New hermetic sealing material for vacuum brazing of stainless steels

NASA Astrophysics Data System (ADS)

Hildebrandt, S.; Wiehl, G.; Silze, F.

2016-03-01

For vacuum brazing applications such as in vacuum interrupter industry Hermetic Sealing Materials (HSM) with low partial pressure are widely used. AgCu28 dominates the hermetic sealing market, as it has a very good wetting behavior on copper and metallized ceramics. Within recent decades wetting on stainless steel has become more and more important. However, today the silver content of HSMs is more in focus than in the past decades, because it has the biggest impact on the material prices. Umicore Technical Materials has developed a new copper based HSM, CuAg40Ga10. The wettability on stainless steel is significantly improved compared to AgCu28 and the total silver content is reduced by almost 44%. In this article the physical properties of the alloy and its brazed joints will be presented compared to AgCu28.

14 CFR 25.1433 - Vacuum systems.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Vacuum systems. 25.1433 Section 25.1433 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There...

The thin-wall tube drift chamber operating in vacuum (prototype)

NASA Astrophysics Data System (ADS)

Alexeev, G. D.; Glonti, L. N.; Kekelidze, V. D.; Malyshev, V. L.; Piskun, A. A.; Potrbenikov, Yu. K.; Rodionov, V. K.; Samsonov, V. A.; Tokmenin, V. V.; Shkarovskiy, S. N.

2013-08-01

The goal of this work was to design drift tubes and a chamber operating in vacuum, and to develop technologies for tubes independent assembly and mounting in the chamber. These design and technology were tested on the prototype. The main features of the chamber are the following: the drift tubes are made of flexible mylar film (wall thickness 36 μm, diameter 9.80 mm, length 2160 mm) using ultrasonic welding along the generatrix; the welding device and methods were developed at JINR. Drift tubes with end plugs, anode wires and spacers were completely assembled outside the chamber. "Self-centering" spacers and bushes were used for precise setting of the anode wires and tubes. The assembled tubes were sealed with O-rings in their seats in the chamber which simplified the chamber assembling. Moreover the tube assembly and the chamber manufacture can be performed independently and in parallel; this sufficiently reduces the total time of chamber manufacture and assembling, its cost and allows tubes to be tested outside the chamber. The technology of independent tube assembling is suitable for a chamber of any shape but a round chamber is preferable for operation in vacuum. Single channel amplifier-discriminator boards which are more stable against cross talks were used for testing the tubes. Independently assembled tubes were mounted into the chamber prototype and its performance characteristic measured under the vacuum conditions. The results showed that both the structure and the tubes themselves normally operate. They are suitable for making a full-scale drift chamber for vacuum.

Hydrothermal Liquefaction Biocrude Compositions Compared to Petroleum Crude and Shale Oil

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

Jarvis, Jacqueline M.; Billing, Justin M.; Hallen, Richard T.

We provide a direct and detailed comparison of the chemical composition of petroleum crude oil (from the Gulf of Mexico), shale oil, and three biocrudes (i.e., clean pine, microalgae Chlorella sp., and sewage sludge feedstocks) generated by hydrothermal liquefaction (HTL). Ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) reveals that HTL biocrudes are compositionally more similar to shale oil than petroleum crude oil and that only a few heteroatom classes (e.g., N1, N2, N1O1, and O1) are common to organic sediment- and biomass-derived oils. All HTL biocrudes contain a diverse range of oxygen-containing compounds when compared tomore » either petroleum crude or shale oil. Overall, petroleum crude and shale oil are compositionally dissimilar to HTL oils, and >85% of the elemental compositions identified within the positive-ion electrospray (ESI) mass spectra of the HTL biocrudes were not present in either the petroleum crude or shale oil (>43% for negative-ion ESI). Direct comparison of the heteroatom classes that are common to both organic sedimentand biomass-derived oils shows that HTL biocrudes generally contain species with both smaller core structures and a lower degree of alkylation relative to either the petroleum crude or the shale oil. Three-dimensional plots of carbon number versus molecular double bond equivalents (with observed abundance as the third dimension) for abundant molecular classes reveal the specific relationship of the composition of HTL biocrudes to petroleum and shale oils to inform the possible incorporation of these oils into refinery operations as a partial amendment to conventional petroleum feeds.« less

Researches on Position Detection for Vacuum Switch Electrode

NASA Astrophysics Data System (ADS)

Dong, Huajun; Guo, Yingjie; Li, Jie; Kong, Yihan

2018-03-01

Form and transformation character of vacuum arc is important influencing factor on the vacuum switch performance, and the dynamic separations of electrode is the chief effecting factor on the transformation of vacuum arcs forms. Consequently, how to detect the position of electrode to calculate the separations in the arcs image is of great significance. However, gray level distribution of vacuum arcs image isn’t even, the gray level of burning arcs is high, but the gray level of electrode is low, meanwhile, the forms of vacuum arcs changes sharply, the problems above restrict electrode position detection precisely. In this paper, algorithm of detecting electrode position base on vacuum arcs image was proposed. The digital image processing technology was used in vacuum switch arcs image analysis, the upper edge and lower edge were detected respectively, then linear fitting was done using the result of edge detection, the fitting result was the position of electrode, thus, accurate position detection of electrode was realized. From the experimental results, we can see that: algorithm described in this paper detected upper and lower edge of arcs successfully and the position of electrode was obtained through calculation.

Advanced Photon Source accelerator ultrahigh vacuum guide

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

Liu, C.; Noonan, J.

1994-03-01

In this document the authors summarize the following: (1) an overview of basic concepts of ultrahigh vacuum needed for the APS project, (2) a description of vacuum design and calculations for major parts of APS, including linac, linac waveguide, low energy undulator test line, positron accumulator ring (PAR), booster synchrotron ring, storage ring, and insertion devices, and (3) cleaning procedures of ultrahigh vacuum (UHV) components presently used at APS.

Ceramic vacuum tubes for geothermal well logging

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

Kelly, R.D.

1977-01-01

Useful design data acquired in the evaluation of ceramic vacuum tubes for the development of a 500/sup 0/C instrumentation amplifier are presented. The general requirements for ceramic vacuum tubes are discussed for application to the development of high temperature well logs. Commercially available tubes are described and future contract activities that specifically relate to ceramic vacuum tubes are detailed. Supplemental data are presented in the appendix.

46 CFR 105.10-20 - Pressure vacuum relief valve.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2011-10-01 2011-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...

46 CFR 105.10-20 - Pressure vacuum relief valve.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2010-10-01 2010-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...

46 CFR 105.10-20 - Pressure vacuum relief valve.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2014-10-01 2014-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...

46 CFR 105.10-20 - Pressure vacuum relief valve.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2012-10-01 2012-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...

46 CFR 105.10-20 - Pressure vacuum relief valve.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in enclosed... 46 Shipping 4 2013-10-01 2013-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10...

7 CFR 58.913 - Evaporators and vacuum pans.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 3 2010-01-01 2010-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...

7 CFR 58.913 - Evaporators and vacuum pans.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 3 2014-01-01 2014-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...

7 CFR 58.913 - Evaporators and vacuum pans.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 3 2011-01-01 2011-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...

7 CFR 58.913 - Evaporators and vacuum pans.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 3 2013-01-01 2013-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...

7 CFR 58.913 - Evaporators and vacuum pans.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 3 2012-01-01 2012-01-01 false Evaporators and vacuum pans. 58.913 Section 58.913....913 Evaporators and vacuum pans. All equipment used in the removal of moisture from milk or milk... Sanitary Standards for Milk and Milk Products Evaporators and Vacuum Pans. ...

Development of secondary chamber for tar cracking-improvement of wood pyrolysis performance in pre-vacuum chamber

NASA Astrophysics Data System (ADS)

Siahaan, S.; Homma, H.; Homma, H.

2018-02-01

Energy crisis and global warming, in other words, climate change are critical topics discussed in various parts of the world. Global warming primarily result from too much emission of carbon dioxide (CO2) in the atmosphere. To mitigate global warming, or climate change and improve electrification in rural areas, wood pyrolysis technology is developed in a laboratory scale, of which gases are directly applicable to the gas engine generator. Our laboratory has developed a prototype of wood pyrolysis plant with a pre-vacuum chamber. However, tar yield was around 40 wt% of feedstock. This research aims to reduce tar yield by secondary tar cracking. For the secondary tar cracking, a secondary pre-vacuum chamber is installed after primary pre-vacuum chamber. Gases generated in the primary pre-vacuum chamber are lead into the secondary chamber that is heated up to 1000 K. This paper reports performance of the secondary chamber for secondary tar cracking in homogeneous mode and heterogeneous mode with char.

Flux tubes in the SU(3) vacuum: London penetration depth and coherence length

NASA Astrophysics Data System (ADS)

Cea, Paolo; Cosmai, Leonardo; Cuteri, Francesca; Papa, Alessandro

2014-05-01

Within the dual superconductor scenario for the QCD confining vacuum, the chromoelectric field generated by a static qq¯ pair can be fitted by a function derived, by dual analogy, from a simple variational model for the magnitude of the normalized order parameter of an isolated Abrikosov vortex. Previous results for the SU(3) vacuum are revisited, but here the transverse chromoelectric field is measured by means of the connected correlator of two Polyakov loops and, in order to reduce noise, the smearing procedure is used instead of cooling. The penetration and coherence lengths of the flux tube are then extracted from the fit and compared with previous results.

Siphonic Concepts Examined: A Carbon Dioxide Gas Siphon and Siphons in Vacuum

ERIC Educational Resources Information Center

Ramette, Joshua J.; Ramette, Richard W.

2011-01-01

Misconceptions of siphon action include assumptions that intermolecular attractions play a key role and that siphons will operate in a vacuum. These are belied by the siphoning of gaseous carbon dioxide and behaviour of siphons under reduced pressure. These procedures are suitable for classroom demonstrations. The principles of siphon action are…

Measuring efficiency of international crude oil markets: A multifractality approach

NASA Astrophysics Data System (ADS)

Niere, H. M.

2015-01-01

The three major international crude oil markets are treated as complex systems and their multifractal properties are explored. The study covers daily prices of Brent crude, OPEC reference basket and West Texas Intermediate (WTI) crude from January 2, 2003 to January 2, 2014. A multifractal detrended fluctuation analysis (MFDFA) is employed to extract the generalized Hurst exponents in each of the time series. The generalized Hurst exponent is used to measure the degree of multifractality which in turn is used to quantify the efficiency of the three international crude oil markets. To identify whether the source of multifractality is long-range correlations or broad fat-tail distributions, shuffled data and surrogated data corresponding to each of the time series are generated. Shuffled data are obtained by randomizing the order of the price returns data. This will destroy any long-range correlation of the time series. Surrogated data is produced using the Fourier-Detrended Fluctuation Analysis (F-DFA). This is done by randomizing the phases of the price returns data in Fourier space. This will normalize the distribution of the time series. The study found that for the three crude oil markets, there is a strong dependence of the generalized Hurst exponents with respect to the order of fluctuations. This shows that the daily price time series of the markets under study have signs of multifractality. Using the degree of multifractality as a measure of efficiency, the results show that WTI is the most efficient while OPEC is the least efficient market. This implies that OPEC has the highest likelihood to be manipulated among the three markets. This reflects the fact that Brent and WTI is a very competitive market hence, it has a higher level of complexity compared against OPEC, which has a large monopoly power. Comparing with shuffled data and surrogated data, the findings suggest that for all the three crude oil markets, the multifractality is mainly due to long

Well-to-refinery emissions and net-energy analysis of China's crude-oil supply

NASA Astrophysics Data System (ADS)

Masnadi, Mohammad S.; El-Houjeiri, Hassan M.; Schunack, Dominik; Li, Yunpo; Roberts, Samori O.; Przesmitzki, Steven; Brandt, Adam R.; Wang, Michael

2018-03-01

Oil is China's second-largest energy source, so it is essential to understand the country's greenhouse gas emissions from crude-oil production. Chinese crude supply is sourced from numerous major global petroleum producers. Here, we use a per-barrel well-to-refinery life-cycle analysis model with data derived from hundreds of public and commercial sources to model the Chinese crude mix and the upstream carbon intensities and energetic productivity of China's crude supply. We generate a carbon-denominated supply curve representing Chinese crude-oil supply from 146 oilfields in 20 countries. The selected fields are estimated to emit between 1.5 and 46.9 g CO2eq MJ-1 of oil, with volume-weighted average emissions of 8.4 g CO2eq MJ-1. These estimates are higher than some existing databases, illustrating the importance of bottom-up models to support life-cycle analysis databases. This study provides quantitative insight into China's energy policy and the economic and environmental implications of China's oil consumption.

Vacuum coupling of rotating superconducting rotor

DOEpatents

Shoykhet, Boris A.; Zhang, Burt Xudong; Driscoll, David Infante

2003-12-02

A rotating coupling allows a vacuum chamber in the rotor of a superconducting electric motor to be continually pumped out. The coupling consists of at least two concentric portions, one of which is allowed to rotate and the other of which is stationary. The coupling is located on the non-drive end of the rotor and is connected to a coolant supply and a vacuum pump. The coupling is smaller in diameter than the shaft of the rotor so that the shaft can be increased in diameter without having to increase the size of the vacuum seal.

Geospatial Hydrochemical and Microbiological Implications on the Occurrence of Crude Oil Biodegradation and Methanogenesis

NASA Astrophysics Data System (ADS)

Shelton, J.; McIntosh, J. C.; Warwick, P.; McCray, J. E.

2014-12-01

Technologies that serve as a bridge between renewable energy and fossil fuels are needed to meet growing energy demands and to mitigate climate change. Many reservoirs contain difficult to produce residual and/or heavily biodegraded (i.e., geochemically altered) crude oil, which remains a relatively untapped resource. Production of this residual crude oil via unconventional methods, such as enhanced oil recovery (EOR), has offset some of the decline in conventional oil production. EOR is not efficient enough to recover all of the original oil in place, and some methods are not effective for very heavy crude oils. Stimulation of in-situ microorganisms to convert the residual crude oil to natural gas (i.e., microbial methane) is one promising strategy to "extract" residual and /or heavy crude oil. Although the hydrogeochemical conditions necessary for the occurrence of both crude oil biodegradation and microbial methanogenesis in various reservoirs have been studied, there are still gaps in research. Many hydrogeochemical factors have been researched individually (not as part of a multifactor or lithologically similar system) and little work has assessed the microbiological limitations of both processes. Our goal is to determine the hydrogeochemical and microbiological conditions required for maximum crude oil biodegradation and microbial methanogenesis across a lithologically similar unit. Produced water, oil, gas, and microbial biomass samples were collected from wells completed in the Paleocene—Eocene Wilcox Group in central Louisiana. Initial results indicate potential relationships between the amount of crude oil biodegradation, indicators of microbial methanogenesis, and aqueous geochemistry. For example, produced waters with the lowest salinity had the highest crude oil biodegradation, and wells exhibiting the most microbial methane generation produce waters with hydrogeochemical conditions most fit for methanogenesis to occur. In sampled wells displaying

Geochemical study of crude oils from the Xifeng oilfield of the Ordos basin, China

NASA Astrophysics Data System (ADS)

Duan, Y.; Wang, C. Y.; Zheng, C. Y.; Wu, B. X.; Zheng, G. D.

2008-01-01

The Xifeng oilfield is the largest newly-discovered oilfield in the Ordos basin. In order to determine the possible source, crude oils collected systematically from the oilfield and an adjacent oilfield have been examined isotopically and molecularly. The predominance of long-chain n-alkanes, high abundance of C 29 sterane, lower ratios of C 25/C 26 tricyclic terpane and C 25 tricyclic terpane/C 24 tetracyclic terpane and high C 24 tetracyclic terpane/(C 24 tetracyclic terpane + C 26 tricyclic terpanes ratio in the studied oils suggest generation from a source with mixed terrigenous and algal-bacterial organic matter. The presence of diterpenoid hydrocarbon with abietane skeletons is characteristic of the main contribution of higher land plants to the oils. The biomarker distributions in the oils show that they were formed under a weakly reducing freshwater environment. Molecular maturity parameters indicate that the crude oils are mature. The oil-source rock correlation and oil migration investigation suggest that the oils in the Xifeng oilfield originated from the source rocks of the Yanchang formation deposited in a shallow to deep freshwater lacustrine environment, especially Chang-7 source rocks. The data from the distribution of pyrrolic nitrogen compounds indicate that the charging direction of the Chang-8 crude oils is mainly from the Zhuang 12 well northeast of the oilfield toward the southwest. This direction of oil migration is consistent with that indicated by regional geological data.

Exploring the WTI crude oil price bubble process using the Markov regime switching model

NASA Astrophysics Data System (ADS)

Zhang, Yue-Jun; Wang, Jing

2015-03-01

The sharp volatility of West Texas Intermediate (WTI) crude oil price in the past decade triggers us to investigate the price bubbles and their evolving process. Empirical results indicate that the fundamental price of WTI crude oil appears relatively more stable than that of the market-trading price, which verifies the existence of oil price bubbles during the sample period. Besides, by allowing the WTI crude oil price bubble process to switch between two states (regimes) according to a first-order Markov chain, we are able to statistically discriminate upheaval from stable states in the crude oil price bubble process; and in most of time, the stable state dominates the WTI crude oil price bubbles while the upheaval state usually proves short-lived and accompanies unexpected market events.

Systematic Engineering of Escherichia coli for d-Lactate Production from Crude Glycerol.

PubMed

Wang, Zei Wen; Saini, Mukesh; Lin, Li-Jen; Chiang, Chung-Jen; Chao, Yun-Peng

2015-11-04

Crude glycerol resulting from biodiesel production is an abundant and renewable resource. However, the impurities in crude glycerol usually make microbial fermentation problematic. This issue was addressed by systematic engineering of Escherichia coli for the production of d-lactate from crude glycerol. First, mgsA and the synthetic pathways of undesired products were eliminated in E. coli, rendering the strain capable of homofermentative production of optically pure d-lactate. To direct carbon flux toward d-lactate, the resulting strain was endowed with an enhanced expression of glpD-glpK in the glycerol catabolism and of a heterologous gene encoding d-lactate dehydrogenase. Moreover, the strain was evolved to improve its utilization of cruder glycerol and subsequently equipped with the FocA channel to export intracellular d-lactate. Finally, the fed-batch fermentation with two-phase culturing was carried out with a bioreactor. As a result, the engineered strain enabled production of 105 g/L d-lactate (99.9% optical purity) from 121 g/L crude glycerol at 40 h. The result indicates the feasibility of our approach to engineering E. coli for the crude glycerol-based fermentation.

Feasibility of low frequency ultrasound for water removal from crude oil emulsions.

PubMed

Antes, Fabiane G; Diehl, Liange O; Pereira, Juliana S F; Guimarães, Regina C L; Guarnieri, Ricardo A; Ferreira, Bianca M S; Dressler, Valderi L; Flores, Erico M M

2015-07-01

The feasibility of indirect application of low frequency ultrasound for demulsification of crude oil was investigated without using chemical demulsifiers. Experiments were performed in an ultrasonic bath with frequency of 35 kHz. Synthetic emulsions with water content of 12%, 35% and 50% and median of droplet size distribution (DSD), median D(0.5), of 5, 10 and 25 μm were prepared from crude oil with API density of 19 (heavy crude oil) and submitted to the proposed ultrasound-assisted demulsification procedure. Experimental conditions as temperature, time of exposition to ultrasound and ultrasonic power were evaluated. Separation of water from crude oil emulsion was observed for all emulsions investigated. Demulsification efficiency up to 65% was obtained for emulsion with 50% of water content and DSD of 10 μm. Higher efficiency of demulsification was achieved using US temperature of 45 °C and ultrasound power of 160 W by 15 min. Results obtained in this study showed that ultrasound could be considered a promising technology for industrial crude oil treatment and respective water removal. Copyright © 2015 Elsevier B.V. All rights reserved.

Level shift two-components autoregressive conditional heteroscedasticity modelling for WTI crude oil market

NASA Astrophysics Data System (ADS)

Sin, Kuek Jia; Cheong, Chin Wen; Hooi, Tan Siow

2017-04-01

This study aims to investigate the crude oil volatility using a two components autoregressive conditional heteroscedasticity (ARCH) model with the inclusion of abrupt jump feature. The model is able to capture abrupt jumps, news impact, clustering volatility, long persistence volatility and heavy-tailed distributed error which are commonly observed in the crude oil time series. For the empirical study, we have selected the WTI crude oil index from year 2000 to 2016. The results found that by including the multiple-abrupt jumps in ARCH model, there are significant improvements of estimation evaluations as compared with the standard ARCH models. The outcomes of this study can provide useful information for risk management and portfolio analysis in the crude oil markets.

Enantioselective Reduction by Crude Plant Parts: Reduction of Benzofuran-2-yl Methyl Ketone with Carrot ("Daucus carota") Bits

ERIC Educational Resources Information Center

Ravia, Silvana; Gamenara, Daniela; Schapiro, Valeria; Bellomo, Ana; Adum, Jorge; Seoane, Gustavo; Gonzalez, David

2006-01-01

The use of biocatalysis and biotransformations are important tools in green chemistry. The enantioselective reduction of a ketone by crude plant parts, using carrot ("Daucus carota") as the reducing agent is presented. The experiment introduces an example of a green chemistry procedure that can be tailored to fit in a regular laboratory session.…

Spacecraft thermal blanket cleaning: Vacuum bake of gaseous flow purging

NASA Technical Reports Server (NTRS)

Scialdone, John J.

1990-01-01

The mass losses and the outgassing rates per unit area of three thermal blankets consisting of various combinations of Mylar and Kapton, with interposed Dacron nets, were measured with a microbalance using two methods. The blankets at 25 deg C were either outgassed in vacuum for 20 hours, or were purged with a dry nitrogen flow of 3 cu. ft. per hour at 25 deg C for 20 hours. The two methods were compared for their effectiveness in cleaning the blankets for their use in space applications. The measurements were carried out using blanket strips and rolled-up blanket samples fitting the microbalance cylindrical plenum. Also, temperature scanning tests were carried out to indicate the optimum temperature for purging and vacuum cleaning. The data indicate that the purging for 20 hours with the above N2 flow can accomplish the same level of cleaning provided by the vacuum with the blankets at 25 deg C for 20 hours, In both cases, the rate of outgassing after 20 hours is reduced by 3 orders of magnitude, and the weight losses are in the range of 10E-4 gr/sq cm. Equivalent mass loss time constants, regained mass in air as a function of time, and other parameters were obtained for those blankets.

Spacecraft thermal blanket cleaning - Vacuum baking or gaseous flow purging

NASA Technical Reports Server (NTRS)

Scialdone, John J.

1992-01-01

The mass losses and the outgassing rates per unit area of three thermal blankets consisting of various combinations of Mylar and Kapton, with interposed Dacron nets, were measured with a microbalance using two methods. The blankets at 25 deg C were either outgassed in vacuum for 20 hours, or were purged with a dry nitrogen flow of 3 cu. ft. per hour at 25 deg C for 20 hours. The two methods were compared for their effectiveness in cleaning the blankets for their use in space applications. The measurements were carried out using blanket strips and rolled-up blanket samples fitting the microbalance cylindrical plenum. Also, temperature scanning tests were carried out to indicate the optimum temperature for purging and vacuum cleaning. The data indicate that the purging for 20 hours with the above N2 flow can accomplish the same level of cleaning provided by the vacuum with the blankets at 25 deg C for 20 hours. In both cases, the rate of outgassing after 20 hours is reduced by 3 orders of magnitude, and the weight losses are in the range of 10E-4 gr/sq cm. Equivalent mass loss time constants, regained mass in air as a function of time, and other parameters were obtained for those blankets.

In-Vacuum Dissociator for Atomic-Hydrogen Masers

NASA Technical Reports Server (NTRS)

Vessot, R. F.

1987-01-01

Thermal control and vacuum sealing achieved while contamination avoided. Simple, relatively inexpensive molecular-hydrogen dissociator for atomic-hydrogen masers used on Earth or in vacuum of space. No air cooling required, and absence of elastomeric O-ring seals prevents contamination. In-vacuum dissociator for atomic hydrogen masers, hydrogen gas in glass dissociator dissociated by radio-frequency signal transmitted from surrounding 3-turn coil. Heat in glass conducted away by contacting metal surfaces.

Vacuum-jacketed transfer line installation technique

NASA Technical Reports Server (NTRS)

Bowers, W. M.

1968-01-01

Rolling-type spacers in the form of steel balls retained in appropriate sleeves affixed at intervals to the exterior of the transfer line facilitate the installation of a vacuum-jacketed line. They act as standoffs to position the transfer line concentrically within the vacuum jacket line.

Vacuum tool manipulator

DOEpatents

Zollinger, William T.

1993-01-01

Apparatus for manipulating a vacuum hose in a reactor vessel comprises a housing with two opposing openings, an arm carried by the housing and deployable from a stowed position essentially completely within the housing to an extended position where the arm extends through the two openings in a generally horizontal position. The arm preferably has a two-fingered gripping device for gripping the vacuum hose but may carry a different end effector such as a grinding wheel. The fingers are opened and closed by one air cylinder. A second air cylinder extends the device. A third air cylinder within the housing pivotally pulls the opposing end of the arm into the housing via a pivoting member pivotally connected between the third air cylinder shaft and the arm.

REVIEWS OF TOPICAL PROBLEMS: Cosmic vacuum

NASA Astrophysics Data System (ADS)

Chernin, Artur D.

2001-11-01

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

Source replenishment device for vacuum deposition

DOEpatents

Hill, Ronald A.

1988-01-01

A material source replenishment device for use with a vacuum deposition apparatus. The source replenishment device comprises an intermittent motion producing gear arrangement disposed within the vacuum deposition chamber. An elongated rod having one end operably connected to the gearing arrangement is provided with a multiarmed head at the opposite end disposed adjacent the heating element of the vacuum deposition apparatus. An inverted U-shaped source material element is releasably attached to the outer end of each arm member whereby said multiarmed head is moved to locate a first of said material elements above said heating element, whereupon said multiarmed head is lowered to engage said material element with the heating element and further lowered to release said material element on the heating element. After vaporization of said material element, second and subsequent material elements may be provided to the heating element without the need for opening the vacuum deposition apparatus to the atmosphere.

Source replenishment device for vacuum deposition

DOEpatents

Hill, R.A.

1986-05-15

A material source replenishment device for use with a vacuum deposition apparatus is described. The source replenishment device comprises an intermittent motion producing gear arrangement disposed within the vacuum deposition chamber. An elongated rod having one end operably connected to the gearing arrangement is provided with a multiarmed head at the opposite end disposed adjacent the heating element of the vacuum deposition apparatus. An inverted U-shaped source material element is releasably attached to the outer end of each arm member whereby said multiarmed head is moved to locate a first of said material elements above said heating element, whereupon said multiarmed head is lowered to engage said material element with the heating element and further lowered to release said material element on the heating element. After vaporization of said material element, second and subsequent material elements may be provided to the heating element without the need for opening the vacuum deposition apparatus to the atmosphere.

Waveguide quantum electrodynamics in squeezed vacuum

NASA Astrophysics Data System (ADS)

You, Jieyu; Liao, Zeyang; Li, Sheng-Wen; Zubairy, M. Suhail

2018-02-01

We study the dynamics of a general multiemitter system coupled to the squeezed vacuum reservoir and derive a master equation for this system based on the Weisskopf-Wigner approximation. In this theory, we include the effect of positions of the squeezing sources which is usually neglected in the previous studies. We apply this theory to a quasi-one-dimensional waveguide case where the squeezing in one dimension is experimentally achievable. We show that while dipole-dipole interaction induced by ordinary vacuum depends on the emitter separation, the two-photon process due to the squeezed vacuum depends on the positions of the emitters with respect to the squeezing sources. The dephasing rate, decay rate, and the resonance fluorescence of the waveguide-QED in the squeezed vacuum are controllable by changing the positions of emitters. Furthermore, we demonstrate that the stationary maximum entangled NOON state for identical emitters can be reached with arbitrary initial state when the center-of-mass position of the emitters satisfies certain conditions.

Effects of Dual-Pump Recovery on Crude-Oil Contamination of Groundwater, Bemidji, Minnesota

NASA Astrophysics Data System (ADS)

Delin, G. N.; Herkelrath, W. N.; Lounsbury, S.

2009-12-01

wells, average oil thicknesses measured in wells at the north pool (0.6 m) and south pool (0.3 m) were largely unaffected. Dissolved-oxygen measurements indicate that a new plume caused by injection of wastewater in the infiltration gallery expanded rapidly immediately following the start of the remediation in 1999. The result was an expansion of the anoxic plume of groundwater upgradient and beneath the existing natural attenuation plume. Vapor sampling results were ambiguous. From 2004-2008, CH4 and CO2 vapor concentrations decreased in upgradient areas above the floating crude oil and increased in downgradient areas above the crude oil. Conversely, O2 vapor concentrations increased in upgradient areas above the floating crude oil and decreased in downgradient areas above the crude oil. Observed changes in vapor concentrations appear to be unrelated to the renewed remediation but instead are consistent with a continuing shift in microbial population from iron reducing to methanogenic conditions. Results indicate that oil phase recovery at this site is challenging, and that considerable volumes of mobile and entrapped oil may still remain in the subsurface in spite of remediation efforts.

Combustion characteristics of crude jatropha oil droplets using rhodium liquid as a homogeneous combustion catalyst

NASA Astrophysics Data System (ADS)

Nanlohy, Hendry Y.; Wardana, I. N. G.; Hamidi, N.; Yuliati, L.

2018-01-01

Combustion characteristics of crude jatropha oil droplet at room temperature with and without catalyst have been studied experimentally. Its combustion characteristics have been observed by igniting the oil droplet on a junction of a thermocouple, and the combustion characteristics of oil droplets are observed using a high-speed camera. The results show that the uniqueness of crude jatropha oil as alternative fuel is evidenced by the different stages of combustion caused by thermal cracking in burning droplets. The results also show that the role of the catalyst is not only an accelerator agent, but there are other unique functions and roles as a stabilizer. Moreover, the results also found that the catalyst was able to shorten the ignition timing and burnout time. This phenomenon proves that the presence of catalysts alters and weakens the structure of the triglyceride geometry so that the viscosity and flash point is reduced, the fuel absorbs heat well and flammable.

Sugar maple sap volume increases as vacuum level is increased

Treesearch

Russell S. Walters; H. Clay Smith

1975-01-01

Maple sap yields collected by using plastic tubing with a vacuum pump increased as the vacuum level was increased. Sap volumes collected at the 10- and 15-inch mercury vacuum levels were statistically significantly higher than volumes collected at the 5-inch level. Although the 15-inch vacuum yielded more sap than the 10-inch vacuum, the difference was not...

Outgassing of solid material into vacuum thermal insulation spaces

NASA Technical Reports Server (NTRS)

Wang, Pao-Lien

1994-01-01

Many cryogenic storage tanks use vacuum between inner and outer tank for thermal insulation. These cryogenic tanks also use a radiation shield barrier in the vacuum space to prevent radiation heat transfer. This shield is usually constructed by using multiple wraps of aluminized mylar and glass paper as inserts. For obtaining maximum thermal performance, a good vacuum level must be maintained with the insulation system. It has been found that over a period of time solid insulation materials will vaporize into the vacuum space and the vacuum will degrade. In order to determine the degradation of vacuum, the rate of outgassing of the insulation materials must be determined. Outgassing rate of several insulation materials obtained from literature search were listed in tabular form.

Mass spectrometer vacuum housing and pumping system

DOEpatents

Coutts, G.W.; Bushman, J.F.; Alger, T.W.

1996-07-23

A vacuum housing and pumping system is described for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof. 7 figs.

Mass spectrometer vacuum housing and pumping system

DOEpatents

Coutts, Gerald W.; Bushman, John F.; Alger, Terry W.

1996-01-01

A vacuum housing and pumping system for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof.

49 CFR 172.327 - Petroleum sour crude oil in bulk packaging.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Bulk packaging used to transport petroleum crude oil containing hydrogen sulfide (i.e., sour crude oil... hydrogen sulfide vapors may occur. (b) The border of the square-on-point must be black or red on a white or...., manhole, loading head) where exposure to hydrogen sulfide vapors may occur. The label, tag, or sign must...

49 CFR 172.327 - Petroleum sour crude oil in bulk packaging.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Bulk packaging used to transport petroleum crude oil containing hydrogen sulfide (i.e., sour crude oil... hydrogen sulfide vapors may occur. (b) The border of the square-on-point must be black or red on a white or...., manhole, loading head) where exposure to hydrogen sulfide vapors may occur. The label, tag, or sign must...

49 CFR 172.327 - Petroleum sour crude oil in bulk packaging.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Bulk packaging used to transport petroleum crude oil containing hydrogen sulfide (i.e., sour crude oil... hydrogen sulfide vapors may occur. (b) The border of the square-on-point must be black or red on a white or...., manhole, loading head) where exposure to hydrogen sulfide vapors may occur. The label, tag, or sign must...

Progress Toward Optimizing Prosthetic Socket Fit and Suspension Using Elevated Vacuum to Promote Residual Limb Health.

PubMed

Wernke, Matthew M; Schroeder, Ryan M; Haynes, Michael L; Nolt, Lonnie L; Albury, Alexander W; Colvin, James M

2017-07-01

Objective: Prosthetic sockets are custom made for each amputee, yet there are no quantitative tools to determine the appropriateness of socket fit. Ensuring a proper socket fit can have significant effects on the health of residual limb soft tissues and overall function and acceptance of the prosthetic limb. Previous work found that elevated vacuum pressure data can detect movement between the residual limb and the prosthetic socket; however, the correlation between the two was specific to each user. The overall objective of this work is to determine the relationship between elevated vacuum pressure deviations and prosthetic socket fit. Approach: A tension compression machine was used to apply repeated controlled forces onto a residual limb model with sockets of different internal volume. Results: The vacuum pressure-displacement relationship was dependent on socket fit. The vacuum pressure data were sensitive enough to detect differences of 1.5% global volume and can likely detect differences even smaller. Limb motion was reduced as surface area of contact between the limb model and socket was maximized. Innovation: The results suggest that elevated vacuum pressure data provide information to quantify socket fit. Conclusions: This study provides evidence that the use of elevated vacuum pressure data may provide a method for prosthetists to quantify and monitor socket fit. Future studies should investigate the relationship between socket fit, limb motion, and limb health to define optimal socket fit parameters.

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

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

Sarantopoulou, E., E-mail: esarant@eie.gr; Stefi, A.; Kollia, Z.

Ultraviolet photons can damage microorganisms, which rarely survive prolonged irradiation. In addition to the need for intact DNA, cell viability is directly linked to the functionality of the cell wall and membrane. In this work, Cladosporium herbarum spore monolayers exhibit high viability (7%) when exposed to 157 nm laser irradiation (412 kJm⁻²) or vacuum-ultraviolet irradiation (110–180 nm) under standard pressure and temperature in a nitrogen atmosphere. Spore viability can be determined by atomic-force microscopy, nano-indentation, mass, μ-Raman and attenuated reflectance Fourier-transform far-infrared spectroscopies and DNA electrophoresis. Vacuum ultraviolet photons cause molecular damage to the cell wall, but radiation resistance inmore » spores arises from the activation of a photon-triggered signaling reaction, expressed via the exudation of intracellular substances, which, in combination with the low penetration depth of vacuum-ultraviolet photons, shields DNA from radiation. Resistance to phototoxicity under standard conditions was assessed, as was resistance to additional environmental stresses, including exposure in a vacuum, under different rates of change of pressure during pumping time and low (10 K) temperatures. Vacuum conditions were far more destructive to spores than vacuum-ultraviolet irradiation, and UV-B photons were two orders of magnitude more damaging than vacuum-ultraviolet photons. The viability of irradiated spores was also enhanced at 10 K. This work, in addition to contributing to the photonic control of the viability of microorganisms exposed under extreme conditions, including decontamination of biological warfare agents, outlines the basis for identifying bio-signaling in vivo using physical methodologies.« less

Physical properties of nanometer graphene oxide films partially and fully reduced by annealing in ultra-high vacuum

NASA Astrophysics Data System (ADS)

Jernigan, Glenn G.; Nolde, Jill A.; Mahadik, Nadeem A.; Cleveland, Erin R.; Boercker, Janice E.; Katz, Michael B.; Robinson, Jeremy T.; Aifer, Edward H.

2017-08-01

The properties of reduced graphene oxide (GO) are reported from a non-chemical reduction method. Ultra-high vacuum annealing of GO films in the thickness of 1-80 nm was studied by XPS, AFM, UV-Vis-NIR, Raman, and TEM to observe the controlled removal of oxygen. We observed the loss of hydroxyl (C-OH) at low temperatures (<600 °C) followed by the complete loss of carbonyls (C = O) and epoxy (C-O-C) species by 1200 °C. As oxygen was removed, we observed a decrease in the layer spacing between the GO sheets and a concurrent decrease in the film resistance. While the Raman spectroscopy showed no change with reduction, indicating no change in the overall defect density or the general structure of the GO, the transmission spectra showed a shift in the transmission minimum from 245 nm to 260 nm, and a total decrease in transmission above 800 nm occurs as the films visibly darken. TEM indicated that there is turbostratic stacking of the graphene layers as the reduction occurs, leading us to conclude that at a certain threshold of reduction the film properties are similar to epitaxial graphene growth on the C-face of SiC, but that a reduction gone too far results in a layer spacing equivalent to graphite.

Crude Oil Metabolites in Groundwater at Two Spill Sites.

PubMed

Bekins, Barbara A; Cozzarelli, Isabelle M; Erickson, Melinda L; Steenson, Ross A; Thorn, Kevin A

2016-09-01

Two groundwater plumes in north central Minnesota with residual crude oil sources have 20 to 50 mg/L of nonvolatile dissolved organic carbon (NVDOC). These values are over 10 times higher than benzene and two to three times higher than Diesel Range Organics in the same wells. On the basis of previous work, most of the NVDOC consists of partial transformation products from the crude oil. Monitoring data from 1988 to 2015 at one of the sites located near Bemidji, MN show that the plume of metabolites is expanding toward a lakeshore located 335 m from the source zone. Other mass balance studies of the site have demonstrated that the plume expansion is driven by the combined effect of continued presence of the residual crude oil source and depletion of the electron accepting capacity of solid phase iron oxide and hydroxides on the aquifer sediments. These plumes of metabolites are not covered by regulatory monitoring and reporting requirements in Minnesota and other states. Yet, a review of toxicology studies indicates that polar metabolites of crude oil may pose a risk to aquatic and mammalian species. Together the results suggest that at sites where residual sources are present, monitoring of NVDOC may be warranted to evaluate the fates of plumes of hydrocarbon transformation products. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

The human health implications of crude oil spills in the Niger delta, Nigeria: An interpretation of published studies.

PubMed

Ordinioha, Best; Brisibe, Seiyefa

2013-01-01

The health hazards created by oil exploration and exploitation are covert and slow in action. They are not given the deserved attention in official documents in Nigeria, even as they can be major contributors to the disease burden in oil-bearing communities. This study is an interpretation of the data reported in several published studies on crude oil spills in the Niger delta region, Nigeria. A manual and Internet search was conducted to extract quantitative data on the quantity of crude oil spilled; the concentrations of the pollutants in surface water, ground water, ambient air and plant and animal tissue; and the direct impact on human health and household food security. An average of 240,000 barrels of crude oil are spilled in the Niger delta every year, mainly due to unknown causes (31.85%), third party activity (20.74%), and mechanical failure (17.04%). The spills contaminated the surface water, ground water, ambient air, and crops with hydrocarbons, including known carcinogens like polycyclic aromatic hydrocarbon and benxo (a) pyrene, naturally occurring radioactive materials, and trace metals that were further bioaccumulated in some food crops. The oil spills could lead to a 60% reduction in household food security and were capable of reducing the ascorbic acid content of vegetables by as much as 36% and the crude protein content of cassava by 40%. These could result in a 24% increase in the prevalence of childhood malnutrition. Animal studies indicate that contact with Nigerian crude oil could be hemotoxic and hepatotoxic, and could cause infertility and cancer. The oil spills in the Niger delta region have acute and long-term effects on human health. Material relief and immediate and long-term medical care are recommended, irrespective of the cause of the spill, to ensure that the potential health effects of exposures to the spills are properly addressed.

Examinations on Laser Remote Welding of Ultra-thin Metal Foils Under Vacuum Conditions

NASA Astrophysics Data System (ADS)

Petrich, Martin; Stambke, Martin; Bergmann, Jean Pierre

Metal foils are commonly used for catalytic converters, vacuum insulations, in medical and electrical industry as well as for sensor applications and packaging. The investigations in this paper determine the influence of reduced atmospheric pressure during the welding process with a highly brilliant 400 W single-mode fiber laser combined with a 2D-scanning system. The laser beam is transmitted through a highly transparent glass into a vacuum chamber, where AISI 304 stainless steel foils with a thickness of 25 μm, 50 μm and 100 μm are positioned. The effects of reduced atmospheric pressure on the plasma formation are investigated by means of high-speed videography. Furthermore, the geometry of the weld seam is compared to atmospheric conditions as well as means of the process stability and the process efficiency. The welds were also evaluated by means of metallography. The research is a contribution for extending the range of micro welding applications and shows new aspects for future developments.

Development of a MEMS-Scale Turbomachinery Based Vacuum Pump

DTIC Science & Technology

2012-06-01

MEMS -SCALE TURBOMACHINERY BASED VACUUM PUMP by Michael J. Shea June 2012 Thesis Advisor: Anthony J. Gannon Second Reader...June 2012 3. REPORT TYPE AND DATES COVERED Master’s Thesis 4. TITLE AND SUBTITLE Development of a MEMS -Scale Turbomachinery Based Vacuum Pump 5...to develop a MEMS scale turbomachinery based vacuum pump. This would allow very high vacuum to be drawn for handheld mass spectroscopy. This

Vacuum system for the SAMURAI spectrometer

NASA Astrophysics Data System (ADS)

Shimizu, Y.; Otsu, H.; Kobayashi, T.; Kubo, T.; Motobayashi, T.; Sato, H.; Yoneda, K.

2013-12-01

The first commissioning experiment of the SAMURAI spectrometer and its beam line was performed in March, 2012. The vacuum system for the SAMURAI spectrometer includes its beam line and the SAMURAI vacuum chamber with the windows for detecting neutrons and charged particles. The window for neutrons was made of stainless steel with a thickness of 3 mm and was designed with a shape of partial cylinder to support itself against the atmospheric pressure. The window for charged particles was of the combination of Kevlar and Mylar with the thickness of 280 and 75 μm, respectively. The pressure in the vacuum system was at a few Pa throughout the commissioning experiment.

Moving characteristics of electrodes for vacuum circuit breaker

NASA Astrophysics Data System (ADS)

Yuan, Shun; Wang, Jimei

1994-05-01

This paper analyzes the effect of the gap of electrodes on the state of vacuum arc by experiment and theory. And the model of vacuum arc is set up. The optimal gap can be deduced from controlling the vacuum arc to be diffusion state, in order to get the optimal moving characteristics of electrodes.