WorldWideScience
1

Degradation of malathion by salt-marsh microorganisms.  

UK PubMed Central (United Kingdom)

Numerous bacteria from a salt-marsh environment are capable of degrading malathion, an organophosphate insecticide, when supplied with additional nutrients as energy and carbon sources. Seven isolates...Full Text Available

1977-02-01

2

How microcystin-degrading bacteria express microcystin degradation activity  

British Library Electronic Table of Contents (United Kingdom)

Abstract Alkali tolerance and the mechanism of microcystin (MC) degradation were investigated in the MC-degrading bacterial species, Sphingopyxis sp. C-1, to better understand the increased MC degradation under the alkaline conditions that arise during the disappearance of water blooms. MC-degrading bacteria harbour mlrA, mlrB and mlrC that encode MC-degrading enzymes. Sphingopyxis sp. C-1 also possesses these genes, as well as the mlrD gene that has been assumed to encode MC and its degradation transporter. This study demonstrated that MC degradation activity was promoted by the intermittent addition of microcystin-LR (MCLR) to cultures of strain C-1. That the expression of mlrA, mlrB and mlrC is induced by MCLR also was indicated, whereas that of mlrA and mlrB is induced by the MCLR degr...

2011-01-01

3

Modification of Spatial Distribution of 2,4-Dichlorophenoxyacetic Acid Degrader Microhabitats during Growth in Soil Columns  

UK PubMed Central (United Kingdom)

Bacterial processes in soil, including biodegradation, require contact between bacteria and substrates. Knowledge of the three-dimensional spatial distribution of bacteria at the microscale is necessary...Full Text Available

2004-05-01

4

Isolation and characterization of quinoline-degrading bacteria from subsurface sediments.  

UK PubMed Central (United Kingdom)

Two gram-negative, motile bacteria isolated from deep subsurface sediments mineralized the nitrogen-containing polyaromatic hydrocarbon quinoline under aerobic conditions and transformed quinoline to...Full Text Available

1989-04-01

5

Microbial treatment of high explosives  

Energy Technology Data Exchange (ETDEWEB)

Both DOE and DOD use water and/or steam in the process of removing high explosives, resulting in large quantities of contaminated water, which is then run through activated carbon, which then has to be decontaminated. Research has been underway to utilize microorganisms to degrade RDX and HMX.

1997-07-01

6

Biotransformation of Explosives by the Old Yellow Enzyme Family of Flavoproteins  

UK PubMed Central (United Kingdom)

Several independent studies of bacterial degradation of nitrate ester explosives have demonstrated the involvement of flavin-dependent oxidoreductases related to the old yellow enzyme (OYE) of yeast....Full Text Available

2004-06-01

7

Eukaryotic Diversity in an Anaerobic Aquifer Polluted with Landfill Leachate?  

UK PubMed Central (United Kingdom)

Eukaryotes may influence pollutant degradation processes in groundwater ecosystems by activities such as predation on bacteria and recycling of nutrients. Culture-independent community profiling and...Full Text Available

2008-07-01

8

Isolation and characterization of a novel gamma-hexachlorocyclohexane-degrading bacterium.  

UK PubMed Central (United Kingdom)

The natural biotic capacity of soils to degrade gamma-hexachlorocyclohexane (gamma-HCH, lindane) was estimated using an enrichment technique based on the ability of soil bacteria to develop on synthetic...Full Text Available

1996-10-01

9

Syntrophic microorganisms in anaerobic environments. Zettai kenki kankyoka ni okeru biseibutsu no kyosei  

Energy Technology Data Exchange (ETDEWEB)

The most classic information on the syntrophic microorganisms in an anaerobic bacteria symbiotic system may be methanobacillus omelianskii. These bacteria were isolated as ones degrading alcohols such as ethanol into methane and were stably preserved for more than 20 years. But, it was clarified by later researches that this was a kind of symbiotic cocultivation system of the bacteria (S strain) which oxidizes ethanol into acetic acid, hydrogen, and carbon dioxide, and a kind of bacteria of the methanobacterium genus which produces or synthesizes methane from hydrogen and carbon dioxide. Such a symbiotic system of two kinds of anaerobic bacteria is the one of a kind of bacteria which produces hydrogen by oxidizing substances and of another kind of bacteria which consume hydrogen. Various kinds of symbiotic systems ...

1992-07-10

10

Low-temperature oxidative degradation of PBX 9501 and its components determined via molecular weight analysis of the Poly[ester urethane] binder  

British Library Electronic Table of Contents (United Kingdom)

The results of following the oxidative degradation of a plastic-bonded explosive (PBX 9501) are reported. Into over 1100 sealed containers were placed samples of PBX 9501 and combinations of its components and aged at relatively low temperatures to induce oxidative degradation of the samples. One of the components of the explosive is a poly(ester urethane) polymer and the oxidative degradation of the samples were following by measuring the molecular weight change of the polymer by gel permeation chromatography (coupled with both differential refractive index and multiangle laser light scattering detectors). Multiple temperatures between 40 and 64 degreeC were used to accelerate the aging of the samples. Interesting induction period behavior, along with both molecular weight increasing (cro...

2009-01-01

11

Thermophilic slurry-phase treatment of petroleum hydrocarbon waste sludges  

Energy Technology Data Exchange (ETDEWEB)

Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The ...

1995-12-31

12

Thermophilic slurry-phase treatment of petroleum hydrocarbon waste sludges  

International Nuclear Information System (INIS)

Chemoheterotrophic thermophilic bacteria were used to achieve enhanced hydrocarbon degradation during slurry-phase treatment of oily waste sludges from petroleum refinery operations. Aerobic and anaerobic bacterial cultures were examined under thermophilic conditions to assess the effects of mode of metabolism on the potential for petroleum hydrocarbon degradation. The study determined that both aerobic and anaerobic thermophilic bacteria are capable of growth on petroleum hydrocarbons. Thermophilic methanogenesis is feasible during the degradation of hydrocarbons when a strict anaerobic condition is achieved in a slurry bioreactor. Aerobic thermophilic bacteria achieved the largest apparent reduction in chemical oxygen demand, freon extractable oil, total and volatile solid,s and polycyclic aromatic hydrocarbons (PAHs) when treating oily waste sludges. The ...

1995-04-24

13

Ecotoxicology of Explosives  

Energy Technology Data Exchange (ETDEWEB)

Managing sites contaminated with munitions constituents is an international challenge. Although the choice of approach and the use of Ecological Risk Assessment (ERA) tools may vary from country to country, the assurance of quality and the direction of ecotoxicological research are universally recognized as shared concerns. Drawing on a multidisciplinary team of contributors, 'Ecotoxicology of Explosives' provides comprehensive and critical reviews available to date on fate, transport, and effects of explosives. The book delineates the state of the science of the ecotoxicology of explosives, past, present, and recently developed. It reviews the accessible fate and ecotoxicological data for energetic materials (EMs) and the methods for their development. The chapters characterize the fate of explosives in the environment, then provide information on their ecological effects in key ...

2009-04-01

14

Energetics and kinetics of anaerobic aromatic and fatty acid degradation  

Science.gov (United States)

The kinetics of benzoate degradation by the anaerobic syntrophic bacterium, Syntrophus buswellii, was studied in coculture with Desulfovibrio strain G11. The threshold value for benzoate degradation was dependent on the acetate concentration with benzoate threshold values ranging from 2.4 [mu]M at 20 mM acetate to 30.0 [mu]M at 65 mM acetate. Increasing acetate concentrations also inhibited the rate of benzoate degradation with a apparent K[sub i] for acetate inhibition of 7.0 mM. Lower threshold values were obtained when nitrate rather than sulfate was the terminal electron acceptor. These data are consistent with a thermodynamic explanation for the threshold, and suggest that there is a minimum Gibbs free energy value required for the degradation of benzoate. An acetoacetyl-CoA thiolase has been isolated from Syntrophomonas wolfei; it is apparently a key enzyme controlling the synthesis of ...

1992-11-16

15

Anaerobic degradation of DCM diffusing through clay  

Energy Technology Data Exchange (ETDEWEB)

Two series of diffusion tests were performed to examine the degradation of dichloromethane (DCM) as it diffuses through clay. The first series showed the use of a synthetic leachate with no significant initial bacterial population diffusing through a plug of intact clay; there was an induction period of 95--135 d, during which diffusion was as expected in the absence of degradation, followed by a second stage, where degradation occurred with an apparent half-life of less than 55 d at a temperature of 24 C. The second series of tests examined the diffusion of an actual leachate from the Keele Valley Landfill (KVL) (which provided both nutrients and a source of bacteria), through a compacted clay. In these tests, the induction period was reduced to 40--60 d, after which the apparent half-life was 20 d or less at 27 C. The diffusion coefficient for DCM was approximately 8 {times} 10{sup {minus}10} m{sup ...

1997-12-01

16

Corrosion of gold bridgewire in electronic components  

Energy Technology Data Exchange (ETDEWEB)

Accelerated aging tests on gold bridgewired detonator assemblies to determine compatibility of the Au and Pd-In-Sn solder with the organic explosive, PENT, have revealed an unusual corrosion process. These tests, conducted at 74/sup 0/C and 54/sup 0/C indicated a preferential attack of the gold. A matrix of corrosion test units was established to study this corrosion problem with accelerating temperatures up to 100/sup 0/C. Scanning electron microscopy (SEM), energy dispersive x-ray (EDX), and x-ray diffraction techniques were used to determine the extent of the corrosion and identify the corrosion products. Results indicate the preferential attack of the gold was due to HCN formed by decomposition of the explosive powder (PETN) at high temperatures. Other associated reactions were also observed including subsequent attack of the solder by the gold corrosion product and degradation of the plastic header.

1986-01-01

17

Dynamic mechanical and molecular weight measurements on polymer bonded explosives from thermally accelerated aging tests. III. Kraton block copolymer binder and plasticizers  

Energy Technology Data Exchange (ETDEWEB)

The dynamic mechanical properties and molecular weight distribution of two experimental polymer bonded explosives, X-0287 and X-0298, maintained at 23, 60, and 74/sup 0/C for 3 years were examined. X-0287 is 97% 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane explosive, 1.8% Kraton G-1650, and 1.2% B/sup 2/ was 170. X-0298 is 97.4% explosive, 1.4% Kraton G-1650, and 1.2% Cenco Hi-vac oil. The relaxation associated with the Kraton rubber block glass transition is observed in both X-0287 and X-0298. In the unaged X-0298 it occurs at -59/sup 0/C and in the aged explosive at 50/sup 0/C. This is caused by migration of the oil plasticizer out of the explosive. In X-0287 the Kraton rubber block T/sub g/ is weak and broad due to the presence of the wax plasticizer. X-0287 has a second broad relaxation associated with the melting of the wax from 10 to 65/sup 0/C. The molecular weight of the ...

1981-01-01

18

Biological treatment of wine of distilleries  

International Nuclear Information System (INIS)

The potential of the yeast Candida tropicalis and Candida guillermondii was evaluated and an isolated partnership of microorganisms of waters of the Medellin River, conformed by two bacteria and one leavening, to degrade the content of organic matter present in wine produced by the factory of Licores and Alcoholes de Antioquia (FLA) in aerobic process with biomass production. For each one of the microorganisms in study this capacity of removal in units of chemical demand of oxygen was quantified (CDO); in addition, parameters were analyzed such as yield of the biomass in relation to the removed CDO and to total reducing sugars (TRS) consumed, time of fermentation and speed of growth different dilutions from wine. Also the possible inhibition was analyzed that the present phenolic compounds in this wine can cause in the biological process of degradation.

19

Degradation of a poly(ester urethane) elastomer. IV. Sorption and diffusion of water in PBX 9501 and its components  

British Library Electronic Table of Contents (United Kingdom)

In preparation for studying the hydrolytic degradation of Estane 5703 in the plastic-bonded explosive PBX 9501, the sorption (solubility) and diffusion of water in PBX 9501 and each of its components are studied experimentally and modeled theoretically. Experiments are reported that measure the weight gain or loss due to a change in the relative humidity (RH). For all of the components, the equilibrium amount of water sorbed per gram of sample is linear in the RH at low relative humidities but curves upwards at higher relative humidities. This behavior is modeled with a water cluster model. Diffusion coefficients are determined by modeling the time dependence of the water concentrations assuming Fickian diffusion, and that fits the data for some of the materials. However, all the samples t...

2007-01-01

20

Isolation of imidacloprid degrading bacteria from industrial sites  

International Nuclear Information System (INIS)

Immidacloprid is a cyclodiene organochlorine used as an insecticide all over the world and possessing a serous environmental threat. It is mostly used for cotton insects (bollworm, aphid and white fly). For isolation of imidacloprid degrading bacteria, two soil samples were collected from industrial contaminated sites of Kala Shah Kahu district sheikupura, having ten year history of use. Soil samples were analyzed by measuring pH and electric conductivity. The isolation of imidacroprid degrading bacteria was performed by enrichment technique. Eight bacterial strains, S/sub 1-a/ S/2-2-b/ S/2-c/ S/2-d/ S/2-e/ S/sub 2-f/ and S/sub 2-g/ and S/sub e-a/ were isolated on the basis of their colony morphologies. The purified colonies were characterized morphologically, physiologically and biochemically. Gram staining was done and Gram negative strain were confirmed on MacConkey agar and Eosin Methylene Blue. ...

22

Engineering of a psychrophilic bacterium for the bioremediation of aromatic compounds  

Science.gov (United States)

Microbial degradation of aromatic hydrocarbons has been studied with the aim of developing applications for the removal of toxic compounds. Efforts have been directed toward the genetic manipulation of mesophilic bacteria to improve their ability to degrade pollutants, even though many pollution problems occur in sea waters and in effluents of industrial processes which are characterized by low temperatures. From these considerations the idea of engineering a psychrophilic microorganism for the oxidation of aromatic compounds was developed.In a previous paper it was demonstrated that the recombinant Antarctic Pseudoalteromonas haloplanktis TAC125 (PhTAC/tou) expressing a toluene-o-xylene monooxygenase (ToMO) is able to convert several aromatic compounds into corresponding catechols. In our work we improved the metabolic capability of PhTAC/tou cells by combining action of recombinant ToMO enzyme with that of the endogenous ...

2010-01-27

23

Means for the Elimination of a Cartridge Rim.  

Science.gov (United States)

... Descriptors : *Combustible cartridge cases, *Patents, Cartridge cases, Explosive trains, Explosives initiators, Consumption. ...

1975-12-30

24

The anaerobic digestion process  

Energy Technology Data Exchange (ETDEWEB)

The microbial process of converting organic matter into methane and carbon dioxide is so complex that anaerobic digesters have long been treated as {open_quotes}black boxes.{close_quotes} Research into this process during the past few decades has gradually unraveled this complexity, but many questions remain. The major biochemical reactions for forming methane by methanogens are largely understood, and evolutionary studies indicate that these microbes are as different from bacteria as they are from plants and animals. In anaerobic digesters, methanogens are at the terminus of a metabolic web, in which the reactions of myriads of other microbes produce a very limited range of compounds - mainly acetate, hydrogen, and formate - on which the methanogens grow and from which they form methane. {open_quotes}Interspecies hydrogen-transfer{close_quotes} and {open_quotes}interspecies formate-transfer{close_quotes} are major mechanisms by which methanogens obtain their ...

1996-01-01

25

Regulation and secretion of Xanthomonas virulence factors  

British Library Electronic Table of Contents (United Kingdom)

Abstract Plant pathogenic bacteria of the genus Xanthomonas cause a variety of diseases in economically important monocotyledonous and dicotyledonous crop plants worldwide. Successful infection and bacterial multiplication in the host tissue often depend on the virulence factors secreted including adhesins, polysaccharides, LPS and degradative enzymes. One of the key pathogenicity factors is the type III secretion system, which injects effector proteins into the host cell cytosol to manipulate plant cellular processes such as basal defense to the benefit of the pathogen. The coordinated expression of bacterial virulence factors is orchestrated by quorum-sensing pathways, multiple two-component systems and transcriptional regulators such as Clp, Zur, FhrR, HrpX and HpaR. Furthermore, virule...

2010-01-01

26

IL-1b enhances the antibacterial activity of astrocytes by activation of NF-kB  

British Library Electronic Table of Contents (United Kingdom)

Astrocytes have important immune functions in CNS, and astrocytes stimulated by interferon-g were showed to have direct antimicrobial function. However whether astrocytes without the stimulation of cytokines have antibacterial function, and how this function is regulated are still largely unknown. In this study, we found that primary cultured astrocytes inhibited the growth of both gram-negative and gram-positive bacteria. Further more, we showed that interleukin-1b (IL-1b) enhanced the antibacterial effect in a dose-dependent manner, and the antibacterial effect of astrocytes from IL-1b receptor-deficient mice failed to be enhanced by IL-1b. IL-1b stimulated IkBa degradation, NF-kB nuclear translocation, and transactivation in astrocytes. NF-kB inhibitors blocked NF-kB activation and the ...

2010-01-01

27

Insensitive fuze train for high explosives  

Energy Technology Data Exchange (ETDEWEB)

A generic insensitive fuze train to initiate insensitive high explosives, such as PBXW-124. The insensitive fuze train uses a slapper foil to initiate sub-gram quantities of an explosive, such as HNS-IV or PETN. This small amount of explosive drives a larger metal slapper onto a booster charge of an insensitive explosive, such as UF-TATB. The booster charge initiates a larger charge of an explosive, such as LX-17, which in turn, initiates the insensitive high explosive, such as PBXW-124.

1994-01-01

28

Evaluation of chicken manure, kenaf, and phanerochaete chrysosporium (white rot fungus) as enhancers of polychlorinated biphenyl biodegradation  

Energy Technology Data Exchange (ETDEWEB)

In this 150-day study, chicken manure, kenaf, and white rot fungus were added to soil microcosms in an attempt to enhance the degradation of polychlorinated biphenyls. The soil was contaminated with commercial PCB mixtures. Dishes were ammended with 5% dry weight chicken manure, 1% dry weight kenaf, and 1% dry weight kenaf plus Phanerochaete chrysosporium inoculant. PCB concentrations were determined at 30 day intervals by soxhlet extraction and gas chromatography analyses. Preliminary results of microbial populations and PCB degradation are presented. At 90 days, the microcosms amended with chicken manure had significantly higher populations of bacteria, fungi, and actinomycetes. However, at 120 days, these soils underwent great reductions in actinomycete and bacterial populations. Through 60 days, the concentration of the PCBs Aroclor 1242 and 1248 had its greatest reduction in the kenaf amended soils. The concentration ...

1995-12-31

29

Adaptation of oral streptococci to low pH.  

Science.gov (United States)

The strategies employed by oral streptococci to resist the inimical influences of acidification reflect the diverse and dynamic niches of the human mouth. All of the oral streptococci are capable of rapid degradation of sugar to acidic end-products. As a result, the pH value of their immediate environment can plummet to levels where glycolysis and growth cease. At this point, the approaches for survival in acid separate the organisms. Streptococcus mutans, for example, relies on its F-ATPase, to protect itself from acidification by pumping protons out of the cells. S. salivarius responds by degrading urea to ammonia and S. sanguis produces ammonia by arginolysis. The mechanisms by which these organisms regulate their particular escape route are now being explored experimentally. The picture that emerges is that the acid-adaptive regulatory mechanisms of the oral streptococci differ markedly from those employed by Gram-negative ...

2000-01-01

30

Explosives - hazard management  

Energy Technology Data Exchange (ETDEWEB)

The management of risks of explosives are described. Administrative and procedural controls are considered. The safety management plan involves hazard identification, risk analysis, assessment and control. The current position of explosives safety is considered. 4 tabs.

1998-12-31

33

Microbiological Comparison of Core and Groundwater Samples Collected from a Fractured Basalt Aquifier with that of Dialysis Chamber Incubated in Situ  

Energy Technology Data Exchange (ETDEWEB)

Microorganisms associated with fractured basalt core were compared to those suspended in groundwater pumped from the same well in the eastern Snake River Plain Aquifer (Idaho, USA). Two wells influenced to different degrees by a mixed-waste plume in the fractured basalt aquifer were examined. In one well, an array of dialysis cells filled with either deionized water or crushed basalt was equilibrated to compare the microorganisms collected in this fashion with those from core and groundwater samples collected in a traditional manner from the same well. Analyses were performed to characterize these samples and to provide a basis for comparison. These included total cell counts by microscopy; total biomass by phospholipid fatty acid analysis; enumerations of viable aerobic heterotrophs, groups of putative aerobic co-metabolic TCE-degraders and aerobic H2-oxidizing bacteria; mineralization of 14C- labeled acetate; and enrichments for dissimilatory ...

2004-04-01

34

Green primary explosives: 5-Nitrotetrazolato-N2-ferrate hierarchies  

UK PubMed Central (United Kingdom)

The sensitive explosives used in initiating devices like primers and detonators are called primary explosives. Successful detonations of secondary explosives are accomplished by suitable sources of...Full Text Available

2006-07-05

36

Determination of the performance of explosives  

Energy Technology Data Exchange (ETDEWEB)

The author attempts to calculate the absolute characteristics of explosives unrelated to the effects of environment, particularly for that part of the work of the explosion done by the expansion of the detonation products. Setting forth his equations and noting their agreement with experimental data, he concludes that for a complete characterization of the relative effectiveness of explosives it is necessary to know the pressure, mass velocity, and polytropic index of the detonation products, but that developed considerations of the relation between performance and detonation characteristics permit a more exact evaluation of various explosives and unification of the nomenclature of explosives and methods of testing them.

1984-11-01

37

Emulsion explosives  

Energy Technology Data Exchange (ETDEWEB)

Emulsion explosives were discovered by Richard S Egley in 1961, but remained little known prior to rapid commercial development in the late 1970s. Their introduction has a significance that may in future be compared with the formulation of dynamite by Nobel in 1867 and the development of ammonium nitrate explosives in the mid 1950s. For the mining engineer emulsion explosives provide advantages of being inherently waterproof and having high strength with a high and stable velocity of detonation giving good fragmentation in hard rock. This is available at moderate cost, from an explosive that typically does not contain any self explosive ingredients and with fume properties that offer considerable advantages over other explosives. 2 figs., 1 tab.

1989-01-01

38

Slurry explosives  

Energy Technology Data Exchange (ETDEWEB)

In a slurry explosive, the fine droplets of the aqueous phase are dispersed in a continuous oily phase which comprises a thin film surrounding each droplet, the latter being less than one micron in size. The authors present these commercial explosives in three different forms, indicate their explosive properties and discuss their advantages from the safety viewpoint. They also report on tests undertaken with slurry explosives in quarries possessing different types of rock and using deep vertical shotholes.

1984-12-01

39

Method and apparatus for detecting explosives  

Energy Technology Data Exchange (ETDEWEB)

A method and apparatus is provided for detecting explosives by thermal imaging. The explosive material is subjected to a high energy wave which can be either a sound wave or an electromagnetic wave which will initiate a chemical reaction in the explosive material which chemical reaction will produce heat. The heat is then sensed by a thermal imaging device which will provide a signal to a computing device which will alert a user of the apparatus to the possibility of an explosive device being present.

2011-05-10

40

Explosives detection: the problem and prospects  

Energy Technology Data Exchange (ETDEWEB)

The history of explosives vapor detection includes almost every detection strategy known to man. Initial attempts to utilize these techniques were dismal failures. However, with the development of the Electron Capture Detector (ECD), the first promising detection of explosives vapors became possible. The present commercial explosives detectors detect the higher vapor pressure materials but not the whole spectrum. This paper describes the basic properties of explosives molecules and our research to utilize these properties for increased detection sensitivity.

1984-01-01

41

Sortases and the Art of Anchoring Proteins to the Envelopes of Gram-Positive Bacteria  

UK PubMed Central (United Kingdom)

The cell wall envelopes of gram-positive bacteria represent a surface organelle that not only functions as a cytoskeletal element but also promotes interactions between bacteria and their environment....Full Text Available

2006-03-01

42

Comparative analysis of nitrifying bacteria associated with freshwater and marine aquaria.  

UK PubMed Central (United Kingdom)

Three nucleic acid probes, two for autotrophic ammonia-oxidizing bacteria of the beta subdivision of the class Proteobacteria and one for alpha subdivision nitrite-oxidizing bacteria, were developed...Full Text Available

1996-08-01

43

Radioisotope space power generator annual report for the period October 1, 1976-September 30, 1978  

Energy Technology Data Exchange (ETDEWEB)

Techniques for fabricating P-type (Cu,Ag)/sub 2/Se with mesh-type bonds have been developed and are being evaluated for long-term use. In addition, methods for reducing vapor suppression by the use of coatings and/or baffling continue to show gains. The N-type alloy Gd/sub 2/Se/sub 3/ has been shown to be thermally unstable. It undergoes a sluggish cubic-to-orthorhombic phase change below 1000/sup 0/C, with an accompanying degradation in mechanical and thermoelectric properties. Fabrication studies conducted with the (Bi,Sb)/sub 2/(Se,Te)/sub 3/ alloys showed these materials to be sensitive to oxygen contamination if reproducible properties are to be obtained. Preparation of powdered material by explosive techniques was investigated. This technique appears to be useful in preparing homogeneous -325 mesh material, but it does not yield a useful amount of submicron-size powder.

1980-01-01

44

Mound Facility explosives incinerator  

Energy Technology Data Exchange (ETDEWEB)

The design and performance of small incinerators used at the Mound Laboratory for the disposal of explosives are described. These units, which cost less than $1000 each, are about the size of a 55-gal drum, have water jackets for cooling, and have provided a flexible, efficient, and clean burning explosives disposal unit. (LCL)

1980-01-01

45

Improved Understanding of Broadband Lg/P Ratio and Its Application to Discriminating Earthquakes from Explosions, Including Decoupled Shots.  

Science.gov (United States)

An understanding of the mechanism of generation of Lg from underground nuclear explosions is essential for seismic monitoring and source discrimination. Near-source scattering of explosion-generated Rg into S appears to be responsible for the low-frequenc...

1996-01-01

46

Explosives detection The problem and prospects  

Energy Technology Data Exchange (ETDEWEB)

Explosives molecules have a number of unique properties. These properties are discussed. They include low vapor pressures, electronegativity, ''stickiness,'' frangibility, and thermal instability. The program for developing an advanced explosives detector is described.

1984-07-01

47

Effect of different nitroheterocyclic compounds on aerobic, microaerophilic, and anaerobic bacteria.  

UK PubMed Central (United Kingdom)

The antibacterial activities of different nitroheterocyclic compounds were assessed by an agar dilution method against aerobic, microaerophilic, and anaerobic bacteria. Nitronaphthofurans inhibited...Full Text Available

1986-11-01

48

Interim explosives detection alternatives  

Energy Technology Data Exchange (ETDEWEB)

There is a general concern with insiders smuggling bomb quantities of explosives into sensitive facilities such as nuclear facilities. At this time, there is no single explosives detection device that is suitable for monitoring personnel and their packages for explosives in an operational facility environment. However, there are techniques combining available commercial technologies with procedures and threat analysis that can significantly increase the insiders risk and reduce the population of adversaries. This paper describes the available applicable explosives detection technologies and discusses the techniques that could be implemented on an interim basis. It is important that these techniques be considered, so that some interim level of security against the explosives threat can be established until more sophisticated equipment that is under development becomes available.

1991-01-01

49

Explosives synthesis at Los Alamos  

Energy Technology Data Exchange (ETDEWEB)

During the past two decades, the explosives synthetic effort at Los Alamos has been directed toward energetic heterocylic compounds and has produced some useful thermally stable explosives. The recent evolution of crystal-density predictive methods is guiding our current efforts toward ultrahigh performance explosives. Much of our effort is now on the development of new methods for preparing unique nitro compounds that are inaccessible by conventional techniques. This paper reviews the Los Alamos synthetic program with emphasis on the development of novel thermally stable explosives, and current efforts to synthesize high-density/performance explosives will be discussed.

1986-03-01

50

Trinitrotoluene: assessment of occupational absorption during manufacture of explosives.  

UK PubMed Central (United Kingdom)

Trinitrotoluene (TNT) absorption was assessed in groups of workers at two explosives factories by measuring the urinary concentrations of dinitroaminotoluene (DNAT) metabolites. DNAT was detected in...Full Text Available

1986-07-01

51

Treatment of persons exposed in radiation accidents or nuclear explosions. Omhaendertagande av skadade vid radiakolyckor och kaernvapenexplosioner  

Energy Technology Data Exchange (ETDEWEB)

The report gives general principles of treatment and care of casualties caused by radiation accidents or nuclear explosions.

1991-01-01

52

REVIEW OF EXPLOSIVE (CHEMICAL) FORMING  

Science.gov (United States)

... explosive (shotgun shells, etc.) method of forming is being replaced--for the most part--by the electri- cal discharge and magnetic forming methods. ...

1965-04-01

53

Hazards of explosives dusts  

Energy Technology Data Exchange (ETDEWEB)

The Bureau of Mines has investigated the hazards of military explosives dispersed as dust clouds in a 20-L test chamber. For purposes of personnel safety, the spark ignitability of the explosives in the form of unconfined dust layers was also studied. The 20-L data show that most of the explosives dusts were capable of sustaining explosions as dust clouds dispersed in air and some dusts were even capable of sustaining explosions when dispersed in nitrogen. The finest sizes of explosives dusts were less reactive than the larger sizes; this is opposite to the particle size effect observed previously for the pure fuel dusts. The data for the explosives dusts were compared to those for pure fuel dusts. 27 refs., 47 figs.

1989-01-01

55

Microbial remediation of soil pollution from ore mining. Part 3: Cyanide removal and biosorption of heavy metals in mining and processing water; Untersuchungen zur mikrobiellen Sicherung von Erzbergbaualtlasten. Teilvorhaben 3: Cyanidabbau und Biosorption von Schwermetallen in Abwaessern aus Erzbergbau- und Aufbereitungsbetrieben. Abschlussbericht  

Energy Technology Data Exchange (ETDEWEB)

1. Cyanide degradation: Of the cyanide- and thiocyanate-degrading bacteria, Burkholderia cepacia and Pseudomonas spec. were the most effective. 2. Biosorption: Of the isolates suited for biosorption of heavy metals, 597-A (non-identifiable) and 597-A2 (Aspergillus fumigatis) had the biggest potential. The sorption capacity of the fungi for metals varied with the C source used for their growth: apple juice > molasses > glucose. The fungi are not cyanide-sensitive and can even degrade cyanide. Living biomass had better metal sorption efficiencies than dead mycelium. The biosorption rates in waste water were usually higher than in broth. Depending on the metal composition and concentrations and on the exposure time and volume of the mycelia, up to 85 % of the initial concentration was removed from the liquid phase. The capacity of different biomasses for the sorption of metal mixtures was ...

1999-12-01

56

Toxicity of N-substituted aromatics to acetoclastic methanogenic activity in granular sludge  

Energy Technology Data Exchange (ETDEWEB)

N-substituted aromatics are important priority pollutants entering the environment primarily through anthropogenic activities associated associated with the industrial production of dyes, explosives, pestides, and pharmaceuticals. Anaerobic treatment of wastewaters discharged by these industries could potentially be problematical as a result of the high toxicity of N-substituted aromatics. The objective of this study was to examine the structure-toxicity relationship of N-substituted aromatic compounds to acetoclastic methanogenic bacteria. The toxicity was assayed to serum flasks by measuring methane production in granular sludge. Unacclimated cultures were used to minimize the biotransformation of the toxic organic chemicals during the test. The nature and the degree of the aromatic substitution were observed to have a profound effect on the toxicity of the test compound. Nitroaromatic compounds were, on the average, over 500-fold more toxic ...

1995-11-01

58

Shale oil explosives  

Energy Technology Data Exchange (ETDEWEB)

Ammonium nitrate shale oil explosives are provided which are effective, powerful, inexpensive, and safe. The explosives contain about 2% to 10% by weight shale oil and about 90% to 98% by weight ammonium nitrate. The shale oil can be whole shale oil or heavy shale oil containing from 0.1% to 65% by weight oil shale dust. The ammonium nitrate is preferably in the form of explosive grade ammonium nitrate prills.

1984-10-09

59

SIMPLIFIED METHODS FOR COMMUNICATING ...  

Science.gov (United States)

... COMBINATION WHICH DISCUSSES AND ILLUSTRATES THE CONSTRUCTION OF AN EXPLODING BRIDGEWIRE ELECTRO-EXPLOSIVE ...

1968-10-01

60

Neutrino processes and pair formation in massive stars and supernovae.  

Science.gov (United States)

Neutrino processes role in star evolution and onset of supernovae explosion

1964-01-01

61

Initiation thresholds of unusual explosives  

Energy Technology Data Exchange (ETDEWEB)

We have used an electric gun to measure the initiation thresholds of more than twenty unusual explosive materials as well as the thresholds of several common explosives for comparison. The purpose of the work was to obtain experimental data for a theoretical study of the effects of various chemical groups on the detonation sensitivity of explosives. 2 refs., 3 figs., 1 tab.

1988-10-01

62

Explosives for mining  

Energy Technology Data Exchange (ETDEWEB)

The explosive known under the name Saletrol (mixture of ammonium nitrate and hydrocarbon fuel or a mixture of ammonium nitrate, hydrocarbon fuel and aluminum powder) is characterized by the absence of physical stability during storage (the oily fluid flows from the upper layers of the explosive downward) and as a consequence of this, decrease in the required effectiveness of blasting and increased release of toxic gaseous blasting products. In order to eliminate this shortcoming, lightening clay is added to Saletrol in a quantity of 3-12% by weight of the total explosive mass.

1982-07-31

63

Explosives and blasting  

Energy Technology Data Exchange (ETDEWEB)

There have been no radically new commercial bulk explosives since Atlas Powder Company's introduction of emulsions onto the market in 1968. But the effectiveness, safety and management of these familiar explosives is continuously being improved by the development of blast design techniques, explosives delivery and initiation systems, and monitoring methods. The author looks at developments in blasting technology and discusses experiences with Handibulk emulsion delivery systems.

1994-02-01

64

Explosion protection in nuclear power plants with LWR and HTR reactors. As of August 14, 1989. Explosionsschutz in Kernkraftwerken mit Leichtwasser- und Hochtemperaturreaktoren (allgemeine und fallbezogene Anforderungen). Vom 14. August 1989  

Energy Technology Data Exchange (ETDEWEB)

The technical rule intends to maintain the function of the safety facilities in case of explosion hazards resulting from materials capable of generating explosive atmospheres or forming explosive mixtures if such materials are brought or released into the nuclear facility or are generated on site. (orig.).

1989-12-07

65

Explosion protection in nuclear power plants with LWR and HTR reactors (general and case depending requirements). Explosionsschutz in Kernkraftwerken mit Leichtwasser- und Hochtemperaturreaktoren (allgemeine und fallbezogene Anforderungen)  

Energy Technology Data Exchange (ETDEWEB)

The technical rule intends to maintain the function of the safety facilities in case of explosion hazards resulting from materials capable of generating explosive atmospheres or forming explosive mixtures if such materials are brought or released into the nuclear facility or are generated on site. (orig.).

1989-01-01

66

Direct process for explosives  

Energy Technology Data Exchange (ETDEWEB)

A direct process of making ethylenediamine dinitrate through the reaction of ethylenediamine and ammonium nitrate.

1982-01-01

67

Direct process for explosives  

Energy Technology Data Exchange (ETDEWEB)

A direct process of making ethylenediamine dinitrate through the reaction of ethylenediamine and ammonium nitrate is described.

1982-10-12

68

Benefits seen in liquid explosives  

Energy Technology Data Exchange (ETDEWEB)

Explosives have been used in the removal of offshore wellhead devices for a number of years. In 1975, the first liquid explosives were run to remove wellheads and have proved to be a safe and reliable method of severing and salvaging the wellhead equipment from most depths of water. Methods of explosive wellhead removal and the areas of safety, reliability, and economics are discussed.

1981-09-01

69

A STUDY TO DETERMINE THE DEFORMATION ...  

Science.gov (United States)

... crystals and polycrystals. Nevertheless, explosive forming, magnetic forming, etc., are all high-strain-rate processes that ...

1963-04-01

70

Suitability of permitted explosives and sheathed explosives for blasting in mines  

Energy Technology Data Exchange (ETDEWEB)

This paper discusses use of chemical explosives for blasting in underground coal mines endangered by methane, and reviews safety regulations on blasting in mines endangered by methane in Poland. Results of tests carried out by the Institute for Mine Safety of the Central Mining Institute in Katowice are reviewed. The following types of explosives were tested: the L permitted Barbaryt, the FGH2 permitted Barbaryt, the D6G permitted Metanit, the D5G permitted Metanit, the W2AG permitted Metanit, the CG sheathed permitted Metanit. Test results are given in a table and 2 diagrams. Comparative evaluations show that the CG sheathed permitted Metanit and the W2AG permitted metanit are superior to other explosives. Methods for evaluating safety of explosives for blasting in coal mines endangered by methane are reviewed. Indices characterizing safety of chemical explosives are evaluated. (3 ...

1983-11-01

71

Relocatable explosives storage magazine  

Energy Technology Data Exchange (ETDEWEB)

A relocatable storage magazine apparatus for storing and retrieving explosives and ordnance and for partially containing and attenuating the blast, conflagration and flying debris from an accidental explosion is described comprising: (a) a container having an access hole; (b) a debris trap attached to the container, the debris trap communicating with said container via the access hole, said debris trap having vent holes for venting the pressure of an explosion from said debris trap to the atmosphere; (c) means for covering said access hole; (d) means for suspending explosives and ordnance from the covering means; (e) means for entering the storage magazine to store and retrieve explosives and ordnance; (f) means for retaining said covering means in a position above the access hole wherein said explosives and ordnance are accessible from the entering means.

1993-06-08

72

DOE explosives safety manual  

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy (DOE) policy requires that all DOE activities be conducted in a manner that protects the safety of the public and provides a safe and healthful workplace for employees. DOE has also prescribed that all personnel be protected in any explosives operation undertaken. The level of safety provided shall be at least equivalent to that of the best industrial practice. The risk of death or serious injury shall be limited to the lowest practicable minimum. DOE and contractors shall continually review their explosives operations with the aim of achieving further refinements and improvements in safety practices and protective features. This manual describes the Department's explosive safety requirements applicable to operations involving the development, testing, handling, and processing of explosives or assemblies containing explosives. It is intended to ...

1991-10-01

73

Explosives Regulation 2005 under the Explosives Act 2003  

Energy Technology Data Exchange (ETDEWEB)

The object of this Regulation is to provide for those matters that may be, or that are required to be, the subject of regulations under the Explosives Act 2003, The Regulation deals with the following maters: a) a register of authorised and prohibited explosives (Part. 2), b) the classification of explosives (Part. 3), c) matters related to licences under the Explosives Act 2003, including the types of licences, requirements for obtaining licences, certain prescribed licence conditions and certain exemptions from the requirement to have a licences (Part. 4), d) specific control measures relating to the handling of explosives (Part. 5), e) matters of a savings, transitional or administrative nature (Part. 1 and 6). This Regulation refers to the following documents: a) AS 2187, Explosives-storage, transport and use, as published by Standards Australia and in force ...

2005-09-02

74

LLNL explosives handbook: properties of chemical explosives and explosives and explosive simulants  

Energy Technology Data Exchange (ETDEWEB)

This handbook presents information and data for high explosives (HEs) of interest to programs at the Lawrence Livermore National Laboratory (LLNL) and other Department of Energy (DOE) facilities. It is intended to be useful to the scientist or engineer, the novice or expert, who needs to develop a new weapon system, design a physics experiment, or select and/or evaluate an existing explosive. This compilation is limited to production HEs and their components. High explosives are divided into two classes: initial detonating (or primary) and noninitiating (or secondary) explosives. The primary HEs, such as azides and fulminates, are extremely sensitive to ignition by heat, shock, and electrical discharge; ignition leads to high-order detonation of the material - even for milligram quantities. The use of these HEs is therefore limited to squibs and starting materials for low-energy detonators. Because ...

1981-03-16

75

Role of periodontal pathogenic bacteria in RANKL-mediated bone destruction in periodontal disease  

UK PubMed Central (United Kingdom)

Accumulated lines of evidence suggest that hyperimmune responses to periodontal bacteria result in the destruction of periodontal connective tissue and alveolar bone. The etiological roles of periodontal...Full Text Available

76

Numerical Taxonomy of Some Bacteria Isolated from Antarctic and Tropical Seawaters1  

UK PubMed Central (United Kingdom)

Pfister, Robert M. (Lamont Geological Observatory, Palisades, N.Y.), and Paul R. Burkholder. Numerical taxonomy of some bacteria isolated from Antarctic and tropical seawaters. J....Full Text Available

1965-10-01

77

Nitrogen Cycling and Community Structure of Proteobacterial ?-Subgroup Ammonia-Oxidizing Bacteria within Polluted Marine Fish Farm Sediments  

UK PubMed Central (United Kingdom)

A multidisciplinary approach was used to study the effects of pollution from a marine fish farm on nitrification rates and on the community structure of ammonia-oxidizing bacteria in the underlying...Full Text Available

1999-01-01

78

Lizards in the ecology of salmonellosis in Panama.  

UK PubMed Central (United Kingdom)

Enteropathogenic bacteria was isolated from 131 of 447 (29.4%) neotropical Panamanian lizards belonging to 34 species of seven families. Overall, 147 strains of bacteria were isolated comprising 26...Full Text Available

1981-05-01

79

Insights into the Genome of Large Sulfur Bacteria Revealed by Analysis of Single Filaments  

UK PubMed Central (United Kingdom)

Marine sediments are frequently covered by mats of the filamentous Beggiatoa and other large nitrate-storing bacteria that oxidize hydrogen sulfide using either oxygen or nitrate, which...Full Text Available

2007-09-01

80

Influence of Species Specificity and Other Factors on Bacteria Associated with the Coral Stylophora pistillata in Taiwan ?  

UK PubMed Central (United Kingdom)

Species of bacteria associated with Stylophora pistillata were determined by analyses of 16S ribosomal genes. Coral samples were taken from two distinct sites at Kenting, in the far...Full Text Available

2009-12-01

81

Identification of immune genes and proteins involved in the response of bovine mammary tissue to Staphylococcus aureus infection  

UK PubMed Central (United Kingdom)

BackgroundMastitis in dairy cattle results from infection of mammary tissue by a range of micro-organisms but principally coliform bacteria and Gram positive bacteria such as Staphylococcus...Full Text Available

82

Growth, cell division and sporulation in mycobacteria  

UK PubMed Central (United Kingdom)

Bacteria have the ability to adapt to different growth conditions and to survive in various environments. They have also the capacity to enter into dormant states and some bacteria form spores when...Full Text Available

2010-08-01

83

Functional Exoenzymes as Indicators of Metabolically Active Bacteria in 124,000-Year-Old Sapropel Layers of the Eastern Mediterranean Sea  

UK PubMed Central (United Kingdom)

Hydrolytic exoenzymes as indicators of metabolically active bacteria were investigated in four consecutive sapropel layers collected from bathyal sediments of the eastern Mediterranean Sea. For comparison,...Full Text Available

2000-06-01

84

Evaluation of broth disk elution methods for susceptibility testing of anaerobic bacteria with the newer beta-lactam antibiotics.  

UK PubMed Central (United Kingdom)

Broth disk elution procedures represent one of the most practical means for clinical laboratories to perform routine antibiotic susceptibility tests on anaerobic bacteria. The accuracy of five disk...Full Text Available

1986-03-01

85

Enrichment of Thermophilic Propionate-Oxidizing Bacteria in Syntrophy with Methanobacterium thermoautotrophicum or Methanobacterium thermoformicicum  

UK PubMed Central (United Kingdom)

Thermophilic propionate-oxidizing, proton-reducing bacteria were enriched from the granular methanogenic sludge of a bench-scale upflow anaerobic sludge bed reactor operated at 55°C with a mixture...Full Text Available

1992-01-01

86

Detection of Unculturable Bacteria in Periodontal Health and Disease by PCR  

UK PubMed Central (United Kingdom)

Recently developed molecular methods have made it possible to characterize mixed microflora in their entirety, including the substantial numbers of bacteria which do not grow on artificial culture media....Full Text Available

1999-05-01

87

Comparison of oral and vaginal metronidazole for treatment of bacterial vaginosis in pregnancy: impact on fastidious bacteria  

UK PubMed Central (United Kingdom)

BackgroundBacterial vaginosis (BV) is a common condition that is associated with preterm birth and acquisition of complex communities of vaginal bacteria that include several fastidious...Full Text Available

88

Chemical structure and inhalation toxicity of lipopolysaccharides from bacteria on cotton.  

UK PubMed Central (United Kingdom)

Lipopolysaccharides from different bacteria isolated from cotton were purified and chemically analyzed. Their pulmonary toxicity to animals was tested in inhalation tests. Lipopolysaccharides from Agrobacterium...Full Text Available

1980-09-01

89

Antibiotic resistance of gram-negative enteric bacteria from pigs in three herds with different histories of antibiotic exposure.  

UK PubMed Central (United Kingdom)

The antibiotic resistance patterns of gram-negative fecal bacteria from pigs in three herds with different histories of antibiotic exposure were examined. In general, smaller proportions of antibiotic-resistant...Full Text Available

1989-09-01

90

AGEs Secreted by Bacteria Are Involved in the Inflammatory Response  

UK PubMed Central (United Kingdom)

Advanced Glycated End Products (AGEs) are formed by non-enzymatic protein glycation and are implicated in several physiological aspects including cell aging and diseases. Recent data indicate that bacteria...Full Text Available

93

Upflow anaerobic sludge reactors for the treatment of combined industrial effluent in subtropical conditions: a comparison between UASB and UASF reactors  

International Nuclear Information System (INIS)

The performance of anaerobic biological process is heavily process conditions dependent. In this study, an attempt has been made to investigate the influence of process conditions like temperature, sludge age and hydraulic retention time (HRT) on the efficiency of an upflow anaerobic sludge blanket (UASB) reactor and upflow anaerobic sludge filter (UASF) to treat combined industrial wastewater. Reactors were operated at easing ambient temperatures (38, 30, 20 and 14 deg. C) and correspondingly increasing sludge ages (60, 90, 120 and 150 days). At temperature 38 deg. C and sludge age of 60 days, UASF showed better performance than VASE reactor. This mainly due to the enhanced filtration through well-graded sand filter and fairly good biological activity in UASF. At this stage, lack of sludge granulation in VASE reactor resulted in poor biological activity; hence, relatively poor performance. At temperatures 30 and 20 deg. C with sludge ages of 90 and 120 days, respectively, UASB gave ...

2004-06-07

94

Development of a microbiological ammonium to nitrate recycling bioreactor for space capsules  

International Nuclear Information System (INIS)

Since 1988, the Expertise group of Molecular and Cellular Biology (MCB) is an important partner in the development of the Micro-Ecological Life Support System Alternative (MELiSSA). The MELiSSA was designed to allow a small crew to survive on an Antarctic, lunar or Mars outpost, and is a joint research project currently fostered by the European Space Agency, ESA. The MELiSSA functions through a series of five interconnected compartments, of which four are microbial bioreactors and was engineered to degrade organic waste, regenerate the outpost's atmosphere and water, and provide the crew with an additional vegetarian diet. The bioreactor of the third compartment provides the edible cyanobacteria and plants of the fourth compartment with nitrate instead of ammonium as a source of nitrogen. The two bacteria responsible for the biological transformation of ammonium to nitrate (nitrification) are Nitrosomonas europaea and Nitrobacter winogradskyi. ...

2009-09-01

95

The influence of the explosion of the conductor of an electric cable on the dielectric properties of the polymer insulator  

British Library Electronic Table of Contents (United Kingdom)

The electric explosion of a conductor being part of an electric cable is studied. It is ascertained that the electric properties of a polymeric dielectric depend nonlinearly on the maintenance of the ultradisperse metal filler. In the course of the numerous heating-cooling processes of an insulator, a streamlining of the structure of a polymeric composite occurs.

2010-01-01

96

DOE explosives safety manual  

Energy Technology Data Exchange (ETDEWEB)

The Department of Energy (DOE) policy requires that all activities be conducted in a manner that protects the safety of the public and provides a safe and healthful workplace for employees. DOE has also prescribed that all personnel be protected in any explosives operation undertaken. The level of safety provided shall be at least equivalent to that of the best industrial practice. The risk of death or serious injury shall be limited to the lowest practicable minimum. DOE and contractors shall continually review their explosives operations with the aim of achieving further refinements and improvements in safety practices and protective features. This manual describes the Department's explosive safety requirements applicable to operations involving the development, testing, handling, and processing of explosives or assemblies containing explosives. It is intended to reflect ...

1990-05-01

97

(Packaging regulations for chemical explosives)  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the trip was to visit Nobel Chemicals in Sweden and to confer with the Department of Transportation personnel in Sweden and in England on the technical and regulatory problems in the bulk shipping of the high explosives RDX and HMX. It is customary in the United States (US) to add isopropyl alcohol to the bulk shipment of water-wet high explosives RDX and HMX. The explosives are packed in cloth bags which are placed in plastic-lined fiber drums. The addition of alcohol presumably prevents mildewing of cloth bags and freezing of the wet explosives in cold weather. In Europe, however, these explosives are shipped in polyethylene-lined fiber drums with not less than 15% water only, even in cold weather. Water-wet frozen explosives have not proved to be any more sensitive than its unfrozen counterpart and no mildew problem has been encountered. It ...

1988-02-17

98

In Situ Detection, Isolation, and Physiological Properties of a Thin Filamentous Microorganism Abundant in Methanogenic Granular Sludges: a Novel Isolate Affiliated with a Clone Cluster, the Green Non-Sulfur Bacteria, Subdivision I  

UK PubMed Central (United Kingdom)

We previously showed that very thin filamentous bacteria affiliated with the division green non-sulfur bacteria were abundant in the outermost layer of thermophilic methanogenic sludge granules fed...Full Text Available

2001-12-01

99

The use of combustible metals in explosive incendiary devices  

Energy Technology Data Exchange (ETDEWEB)

We have investigated tailoring damage effects of explosive devices by addition of unconventional materials, specifically combustible metals. Initial small-scale as well as full-scale testing has been performed. The explosives functioned to disperse and ignite these materials. Incendiary, enhanced-blast, and fragment-damage effect have been identified. These types of effects can be used to extend the damage done to hardened facilities. In other cases it is desirable to disable the target with minimal collateral damage. Use of unconventional materials allows the capability to tailor the damage and effects of explosive devices for these and other applications. Current work includes testing of an incendiary warhead for a penetrator.

1996-08-01

100

Some Properties of Australian Produced Explosive ...  

Science.gov (United States)

... The rounds were initiated by an exploding bridgewire detonator (EBW) and the ionisation probes were progressively cloud by the detonation front. ...

1987-10-01

101

Signatures of testing: On-site inspection technologies  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the phenomenology of nuclear explosions and technologies for their detection as relevant to On-Site Inspection (OSI) for a comprehensive test-ban (CTB). Our experience with the US nuclear test program which has been primarily carried out at the Nevada Test Site (NTS) and in the Pacific Ocean. The goals of OSI are to resolve ambiguous events, reduce uncertainty, deter attempts at evasion, and provide responsive and technically competent means of confirming the occurrence of a nuclear explosion should deterrence fail. These goals would include finding evidence of an evasive nuclear explosion or evidence that the event was non-nuclear, such as an earthquake or large chemical explosion.

1995-01-01

102

INITIATION OF EXPLOSIVES BY EXPLODING WIRES. VII. ...  

Science.gov (United States)

... The results should be of interest to personnel engaged in initiation research and design of exploding bridgewire ordnance systems. ...

1965-06-25

103

Explosives 92. Conference proceedings  

Energy Technology Data Exchange (ETDEWEB)

17 papers are presented. Topics covered include: the POG system - a new concept in the use of ANFO; demolition of a motorway bridge; presplit and smooth blasting; VIBReX - a predictive code for assessing the effect of blast design on ground vibration; ground vibrations from blasting; digital seismographs; human response to blasting and the effects on planning conditions; landform construction by restoration blasting; use of small diameter explosives; efficient priming; safety management in the explosives industry; and the law on packaging of explosives. Two papers have been abstracted separately.

1992-01-01

104

Explosive Performance Modification by Cosolidification of ...  

Science.gov (United States)

... A booster pellet, normally Comp B, was placed in the tube and an exploding bridgewire (EBW) detonator in a plastic holder was glued in with a ...

1976-10-01

105

Experimental Testing of a Combustible Case for the 155mm ...  

Science.gov (United States)

... Descriptors : *INTERIOR BALLISTICS, *COMBUSTIBLE CARTRIDGE CASES, FIRING TESTS(ORDNANCE), EXPLOSIVE CHARGES, ARTILLERY ...

1982-03-01

106

EXPLODING BRIDGEWIRE INITIATION OF CAST ...  

Science.gov (United States)

... Accession Number : AD0368940. Title : EXPLODING BRIDGEWIRE INITIATION OF CAST EXPLOSIVES. Descriptive Note : Final rept. ...

1965-12-01

107

A Profile of Defense Manufacturing Costs and Enabling ...  

Science.gov (United States)

... Casting Explosive forming Forging Electrohydraulic forming Extruding Magnetic forming Rolling Electroforming Drawing Powdered metal forming ...

1992-01-01

108

A GENERAL STUDY OF PROCESSES FOR THE ...  

Science.gov (United States)

... fields, materials can be subjected to energy densities exceeding those realized in high explosives, a fact which forms the basis for magnetic forming ...

1962-11-01

109

Thermal hazards of explosives  

Energy Technology Data Exchange (ETDEWEB)

Small-scale methods for determining the reaction rates of explosives that make it possible to predict safe temperatures for using them, and methods for testing the accuracy of these predictions were developed. Each different size and shape of each different explosive has its own critical temperature. The ability to predict these critical temperatures is required before high-energy materials can be used safely.

1981-03-01

110

Improving airport explosives detection  

Energy Technology Data Exchange (ETDEWEB)

ORNL has developed the technology to detect hidden explosives in luggage using X ray and neutron detection devices. The Federal Aviation Administration has ordered the airlines to buy and install Thermal Neutron Analysis (TNA) units. The combined pulsed-neutron and X-ray interrogation inspection (CPNX) system developed at ORNL uses less radioactive materials as well as being more sensitive to weapons, electronic devices and plastic explosives.

1990-01-01

111

High-explosives test facility  

Energy Technology Data Exchange (ETDEWEB)

This report describes a high explosives test facility that makes efficient use of equipment and combines utility, convenience, and safety in a modest amount of space. It is a dedicated facility for exploratory development efforts that previously were conducted in a single room having very limited capabilities. Two explosives testing areas are now available and several projects are supported concurrently.

1982-08-01

112

Explosives simulants: Preliminary report  

Energy Technology Data Exchange (ETDEWEB)

Two TNT high explosives simulants have been developed. Small scale testing has shown them to be insensitive to: impact, spark, friction, temperature, and shock. The materials have been scaled to 0.5 kg quantities and samples given to the Protective Services Department for field evaluation using explosives detecting canines.

1992-03-04

113

Detonation of explosives  

Energy Technology Data Exchange (ETDEWEB)

In recent years new, less-sensitive explosives have been developed together with new types of detonator. Four sections are covered: 1) Description of various developments achieved by the laboratories of Nobel Explosifs over the past 12 years; 2) Explanation of the limits of application of the various products; 3) Thoughts on the various detonator systems and their effectiveness; and 4) Advice and recommendations for the use of the new product range. The products in question are : dynamites, nitrates, oil nitrates, gels and slurry explosives. (17 refs.)

1983-04-01

114

Nuclear explosives for peaceful purposes  

Energy Technology Data Exchange (ETDEWEB)

The US Plowshare program, designed to develop peaceful uses of nuclear explosives, was vigorous between 1957-73 and was of concern during US and USSR nuclear treaty negotiations within that period. In order to accommodate possible future applications, the Peaceful Nuclear Explosions Treaty was signed in 1976. The US program explored the phenomenology of nuclear explosions and tested their use in industrial applications. Due to waning industrial interest and public concern over environmental issues, the US program was terminated in 1977. The Soviet counterpart to the Plowshare program, which has involved more than 100 experiments throughout the USSR, continued until the self-imposed moratorium in 1985. As any peaceful use of nuclear explosives has the potential of furthering weapons research, the US takes the position that all such experiments would have to be banned in a comprehensive test ban treaty. ...

1986-11-01

115

Nuclear explosives for peaceful purposes  

Energy Technology Data Exchange (ETDEWEB)

The US Plowshare programme, designed to develop peaceful uses of nuclear explosives, was vigorous between 1957 to 1973 and was of concern during US and USSR nuclear treaty negotiations within that period. In order to accommodate possible future applications, the Peaceful Nuclear Explosions (PNE) Treaty was signed in 1976. The US programme explored the phenomenology of nuclear explosions and tested their use in industrial applications. Due to waning industrial interest and public concern over environmental issues, the US program was terminated in 1977. The Soviet counterpart to the Plowshare programme, which has involved roughly 100 experiments throughout the USSR, continued until the self-imposed moratorium in 1985. As any peaceful use of nuclear explosives has the potential of furthering weapons research, the US takes the position that all such experiments would have to be banned in a comprehensive ...

1986-07-01

116

Idaho Explosives Detection System  

Energy Technology Data Exchange (ETDEWEB)

The Idaho Explosives Detection System was developed at the Idaho National Laboratory (INL) to respond to threats imposed by delivery trucks potentially carrying explosives into military bases. A full-scale prototype system has been built and is currently undergoing testing. The system consists of two racks, one on each side of a subject vehicle. Each rack includes a neutron generator and an array of NaI detectors. The two neutron generators are pulsed and synchronized. A laptop computer controls the entire system. The control software is easily operable by minimally trained staff. The system was developed to detect explosives in a medium size truck within a 5-min measurement time. System performance was successfully demonstrated with explosives at the INL in June 2004 and at Andrews Air Force Base in July 2004.

2005-12-01

117

Explosive performance on the non-proliferation experiment  

Energy Technology Data Exchange (ETDEWEB)

The non-proliferation experiment, originally called the chemical kiloton experiment, was planned and executed by Lawrence Livermore National Laboratory to investigate the seismic yield relationship and distinguishing seismic signals between a nuclear event and a large mass conventional explosion. The Los Alamos National Laboratory planned and conducted experiments to further their studies of the source function for signals observed seismically. Since all investigations were contingent on the performance of the emplaced chemical explosive, an array of diagnostic measurements was fielded in the emplaced explosive. The CORRTEX system was used to investigate the explosive initiation and to determine the detonation velocities in multiple levels and in numerous directions. A description of the CORRTEX experiments fielded, a review of the data obtained and some interpretations of the data are reported.

1994-03-01

118

Bubble nucleation, growth and coalescence during the 1997 Vulcanian explosions of Soufriere Hills Volcano, Montserrat  

British Library Electronic Table of Contents (United Kingdom)

Soufriere Hills Volcano had two periods of repetitive Vulcanian activity in 1997. Each explosion discharged the contents of the upper 0.5-2km of the conduit as pyroclastic flows and fallout: frothy pumices from a deep, gas-rich zone, lava and breadcrust bombs from a degassed lava plug, and dense pumices from a transition zone. Vesicles constitute 1-66vol.% of breadcrust bombs and 24-79% of pumices, all those larger than a few tens of m being interconnected. Small vesicles (few hundreds of m) in pumices are interpreted as pre-dating explosion, implying pre-explosive conduit porosities up to 55%. About a sixth of large vesicles in pumices, and all those in breadcrust bombs, are angular voids formed by syn-explosive fracturing of amphibole phenocrysts. An intermediate-sized vesicle population...

2010-01-01

119

A simple model for explosives formulation  

Energy Technology Data Exchange (ETDEWEB)

A simple model based on surface chemistry is developed, based an simple concepts of contact angle, wetting and spreading. Results of the modeling can be stated by two simplified rules of thumb'': (1) A liquid will spread on the surface of a solid if the surface tension of the liquid is lose than the surface free energy of the solid, and (2) The liquid having the surface tension nearest that of the solid will preferentially wet the surface of the solid. These two rules can then be used to define the parameters that constitute a process for formulating a plastic bonded explosive (PBX), which is a crystalline high-explosive material coated with a small amount of plastic polymeric material (the binder). The PBX then can be pressed to a high density, and machined to a specific shape. The pressed and machined explosive material can then be used in a physics experiment to study fundamental properties of either ...

1993-01-01

120

A simple model for explosives formulation  

Energy Technology Data Exchange (ETDEWEB)

A simple model based on surface chemistry is developed, based an simple concepts of contact angle, wetting and spreading. Results of the modeling can be stated by two simplified ``rules of thumb``: (1) A liquid will spread on the surface of a solid if the surface tension of the liquid is lose than the surface free energy of the solid, and (2) The liquid having the surface tension nearest that of the solid will preferentially wet the surface of the solid. These two rules can then be used to define the parameters that constitute a process for formulating a plastic bonded explosive (PBX), which is a crystalline high-explosive material coated with a small amount of plastic polymeric material (the binder). The PBX then can be pressed to a high density, and machined to a specific shape. The pressed and machined explosive material can then be used in a physics experiment to study fundamental properties of either the ...

1993-04-01

121

A primer on explosives costs  

Energy Technology Data Exchange (ETDEWEB)

There are a multitude of cost centers in the typical coal mine, and almost as many ways to calculate their individual and collective effect on the bottom line. The costs of explosives is, in some ways, very difficult to determine without consideration of drilling, loading, hauling and breaking costs. Saving a nickel in explosive costs, for example, could end up costing a dollar more in crushing expenses. Typically, mines request quotations for explosives products on a weight basis. Were the market one of pure commodities, this would give a valid comparison. However, the energy being purchased often is not considered. The cost of any explosive should be considered in light of the work it can do, not the air it displaces or the price per pound. Consider in essence, the purchase of explosive energy as you would the sale of coal, in terms of dollars per Btu. Recent new developments in ...

1987-03-01

122

Nylon biodegradation by lignin-degrading fungi.  

UK PubMed Central (United Kingdom)

The biodegradation of nylon by lignin-degrading fungi was investigated. The fungus IZU-154 significantly degraded nylon-66 membrane under ligninolytic conditions. Nuclear magnetic resonance analysis...Full Text Available

1997-01-01

123

Degradation of Proteins Artificially Introduced into Vacuoles of Chara australis1  

UK PubMed Central (United Kingdom)

When an exogenous protein, bovine serum albumin, was introduced into the vacuole of a Chara australis internodal cell, it was degraded with time. This degradation proceeded only in...Full Text Available

1988-12-01

124

The formation and degradation of Ti-Ag and Ti-Pd-Ag solar cell contacts  

Science.gov (United States)

Ti-Ag and Ti-Pd-Ag solar cell contacts structure and degradation dependence on high temperature and humidity environmental exposure

1970-01-01

125

Concerns of Hydrothermal Degradation in CAD/CAM Zirconia  

UK PubMed Central (United Kingdom)

Zirconia-based restorations are widely used in prosthetic dentistry; however, their susceptibility to hydrothermal degradation remains elusive. We hypothesized that CAD/CAM machining and subsequent...Full Text Available

2010-01-01

126

Phytoremediation of Ionic and Methyl Mercury P  

Science.gov (United States)

Our long-term goal is to enable highly productive plant species to extract, resist, detoxify, and/or sequester toxic heavy metal pollutants as an environmentally friendly alternative to physical remediation methods. We have focused this phytoremediation research on soil and water-borne ionic and methylmercury. Mercury pollution is a serious world-wide problem affecting the health of human and wild-life populations. Methylmercury, produced by native bacteria at mercury-contaminated wetland sites, is a particularly serious problem due to its extreme toxicity and efficient biomagnification in the food chain. We engineered several plant species (e.g., Arabidopsis, tobacco, canola, yellow poplar, rice) to express the bacterial genes, merB and/or merA, under the control of plant regulatory sequences. These transgenic plants acquired remarkable properties for mercury remediation. (1) Transgenic plants expressing merB (organomercury lyase) extract methylmercury from their ...

1999-06-01

127

Aging of Pentaerythritol Tetranitrate (PETN)  

Science.gov (United States)

Pentaerythritol tetranitrate (PETN) is a relatively sensitive explosive used in many electroexplosive devices as well as in medicine. Of primary interest to LLNL is its use in items such as exploding bridgewire (EBW) detonators and exploding bridge foil initiators (EFI). In these devices the crystalline powder is pressed into a granular, low-density compact that can be initiated by an exploding wire or foil. The long-term stability of this pressed compact is of interest to weapon stockpile lifetime prediction studies. Key points about potential aging mechanisms can be summarized as follows: (1) There are a number of factors that can contribute to PETN instability. These include particle size, polymorphic phase transitions, crystal structure, impurities, moisture, occlusions, chemical incompatibility and biological (microorganism) action. of these factors the most important for long-term aging of high surface area powders used in detonators appears to be that of ...

2009-04-22

128

Uncoupler-resistant mutants of bacteria.  

UK PubMed Central (United Kingdom)

The chemiosmotic model of energy transduction offers a satisfying and widely confirmed understanding of the action of uncouplers on such processes as oxidative phosphorylation; the uncoupler, by facilitating...Full Text Available

1990-03-01

129

Thermokinetic investigation of effects of carbon source on petroleum bacterial growth  

Energy Technology Data Exchange (ETDEWEB)

The growth power-time curves of a strain of petroleum bacteria, B-2, in various kinds of cultures containing different kinds of carbon sources, glucose, n-tetradecane, n-hexadecane and n-octadecane, and different kinds of microemulsions have been determined by using a 2277 Thermal Activity Monitor. The curves showed a single peak for cultures containing a single carbon source, glucose, and two peaks for cultures containing two kinds of carbon sources, glucose and one of the n-alkanes. The first peak indicated that bacteria grew by consuming glucose and the second peak indicated that bacteria grew by consuming n-alkane. The curves were complex when the bacterium grows in a microemulsion culture. According to a kinetic equation of bacterial growth under limited conditions, the rate constants of bacterial growth were obtained. The results showed that the microemulsion culture was more appropriate to ...

2002-02-07

130

Sirtuins, Bioageing, and Cancer  

UK PubMed Central (United Kingdom)

The Sirtuins are a family of orthologues of yeast Sir2 found in a wide range of organisms from bacteria to man. They display a high degree of conservation between species, in both sequence and function,...Full Text Available

131

Probiotic Bacteria as Biological Control Agents in Aquaculture  

UK PubMed Central (United Kingdom)

There is an urgent need in aquaculture to develop microbial control strategies, since disease outbreaks are recognized as important constraints to aquaculture production and trade and since the development...Full Text Available

2000-12-01

132

Growth regulation of Legionella Pneumophila in biofilms and amoebae; Wachstumsregulation von Legionella Pneumophila in Biofilmen und Amoeben  

Energy Technology Data Exchange (ETDEWEB)

This final report for the Swiss Federal Office of Energy (SFOE) presents the results of studies made on the regulation of the growth of Legionella Pneumophila bacteria in biofilms and amoebae. In a first project, the formation of biofilms by Legionella Pneumophila bacteria was analysed in static and dynamic systems using a complex growth medium. Under static and dynamic clinical and environmental conditions, the adherence of the biofilms on polystyrene tissue was studied. This was also examined under dynamic flow conditions. In a second part of the project, the regulation of growth of Legionella Pneumophila in amoebae was examined in that changes were made to the genome of the bacteria. The importance of the work for the de-activation of Legionella Pneumophila bacteria in biofilms is noted in the conclusions of the report.

2006-07-01

133

Factors Influencing the Effectiveness of Swimming Pool Bactericides  

UK PubMed Central (United Kingdom)

Techniques for culturing, harvesting, and testing bacteria to evaluate bactericidal chemicals for swimming pools are described. Concentrations of 25, 50, and 100 mg of the chlorine stabilizer cyanuric...Full Text Available

1967-05-01

134

FLUOROMETRIC MEASUREMENT OF OXIDATIVE BURST IN LOBSTER HEMOCYTES AND INHIBITING EFFECT OF PATHOGENIC BACTERIA AND ...  

Science.gov (United States)

... Hunter. 2003. The resistance to ammonia stress of Penaeus monodon Fabricius juveniles fed diets supplemented with astaxanthin. J. Exp. ... ...

135

Detection and Identification of Bacteria by Gas Chromatography1  

UK PubMed Central (United Kingdom)

Ether extracts of cultures of 29 strains representing 6 species of Bacillus, and of individual strains of Escherichia coli, Aerobacter aerogenes, and Pseudomonas...Full Text Available

1966-07-01

136

Biosorption of heavy metal ions on Rhodobacter sphaeroides and Alcaligenes eutrophus H16  

Energy Technology Data Exchange (ETDEWEB)

A fundamental study of the application of bacteria to the recovery of toxic heavy metals from aqueous environments was carried out. The biosorption characteristics of cadmium and lead ions were determined with purple nonsulfur bacteria, Rhodobacter sphaeroides and hydrogen bacteria, Alcaligenes eutrophus H16 that were inactivated by steam sterilization. A simplified version of the metal binding model proposed by Plette et al. was used for the description of meal binding data. The results showed that the biosorption of bivalent metal ions to whole cell bodies of the bacteria was due to monodentate binding to two different types of acidic sites: carboxilic and phosphatic-type sites. The number of metal binding sites of A. eutrophus was 2.4-fold larger than that of R. sphaeroides.

1998-01-15

137

Thermodynamic Model of Aluminum Combustion in SDF Explosions  

Energy Technology Data Exchange (ETDEWEB)

Thermodynamic states encountered during combustion of Aluminum powder in Shock-Dispersed-Fuel (SDF) explosions were analyzed with the Cheetah code. Results are displayed in the Le Chatelier diagram: the locus of states of specific internal energy versus temperature. Accuracy of the results was confirmed by comparing the fuel and products curves with the heats of detonation and combustion, and species composition as measured in bomb calorimeter experiments. Results were fit with analytic functions u = f(T) suitable for specifying the thermodynamic properties required for gas-dynamic models of combustion in explosions.

2006-06-19

138

Phenomena of Time Resonances Explosions for the Compound-Clot Decays in High-Energy Nuclear Reactions  

CERN Document Server

The phenomenon of time resonances (or explosions) can explain the exponential reduction of the energy, which is accompanied for the certain degree by slight fluctuations under some conditions in the range of the energy strongly overlapped compound-resonances. These resonant explosions correspond to formation of several highly-exited non-exponentially decaying nuclear clots (partial compound nuclei consisting of several small groups of projectile nucleons and targets). This paper is a continuation and expansion of theoretical authors' work, which is a more general self-consistent version of the time-evolution approach in comparison with the traditional Izumo-Araseki time compound-nucleus model.

2009-01-01

139

Nonequilibrium detonation of composite explosives  

Energy Technology Data Exchange (ETDEWEB)

The effect of nonequilibrium diffusional flow on detonation velocities in composite explosives is examined. Detonation conditions are derived for complete equilibrium, temperature and pressure equilibrium, and two forms of pressure equilibrium. Partial equilibria are associated with systems which have not had sufficient time for transport to smooth out the gradients between spatially separate regions. The nonequilibrium detonation conditions are implemented in the CHEQ equation of state code. We show that the detonation velocity decreases as the non-chemical degrees of freedom of the explosive are allowed to equilibrate. It is only when the chemical degrees of freedom are allowed to equilibrate that the detonation velocity increases. {copyright} {ital 1998 American Institute of Physics.}

1998-07-01

140

Microcantilever detector for explosives  

Energy Technology Data Exchange (ETDEWEB)

Methods and apparatus for detecting the presence of explosives by analyzing a vapor sample from the suspect vicinity utilize at least one microcantilever. Explosive gas molecules which have been adsorbed onto the microcantilever are subsequently heated to cause combustion. Heat, along with momentum transfer from combustion, causes bending and a transient resonance response of the microcantilever which may be detected by a laser diode which is focused on the microcantilever and a photodetector which detects deflection of the reflected laser beam caused by heat-induced deflection and resonance response of the microcantilever. 2 figs.

1999-06-29

141

Method and system for detecting explosives  

Energy Technology Data Exchange (ETDEWEB)

A method of detecting explosives in a vehicle includes providing a first rack on one side of the vehicle, the rack including a neutron generator and a plurality of gamma ray detectors; providing a second rack on another side of the vehicle, the second rack including a neutron generator and a plurality of gamma ray detectors; providing a control system, remote from the first and second racks, coupled to the neutron generators and gamma ray detectors; using the control system, causing the neutron generators to generate neutrons; and performing gamma ray spectroscopy on spectra read by the gamma ray detectors to look for a signature indicative of presence of an explosive. Various apparatus and other methods are also provided.

2009-03-10

142

Explosives detection system and method  

Energy Technology Data Exchange (ETDEWEB)

A method of detecting explosives in a vehicle includes providing a first rack on one side of the vehicle, the rack including a neutron generator and a plurality of gamma ray detectors; providing a second rack on another side of the vehicle, the second rack including a neutron generator and a plurality of gamma ray detectors; providing a control system, remote from the first and second racks, coupled to the neutron generators and gamma ray detectors; using the control system, causing the neutron generators to generate neutrons; and performing gamma ray spectroscopy on spectra read by the gamma ray detectors to look for a signature indicative of presence of an explosive. Various apparatus and other methods are also provided.

2007-12-11

143

Compaction of salt by means of explosives  

Energy Technology Data Exchange (ETDEWEB)

One of the concerns with locating radioactive waste storage sites in salt deposits is how to permanently seal the underground storage areas once they have reached their storage capacity. The compaction of salt using explosives has been identified as a potential method of producing permanent seals in both entryways and shafts to storage areas. This paper describes the test procedure and results of a preliminary investigation to determine the feasibility of utilizing explosives in the compaction of salt. Three simple tests were carried out to measure the degree to which loose salt could be compacted.

1996-12-01

146

Prediction of the gain degradation induced by neutrons in dipolar transistors: spectrum dependence, electrical characteristic correlations  

International Nuclear Information System (INIS)

An original evaluating method of gain degradation has been found for neutron irradiated transistors. It establishes a correlation between degradation and the product of two coefficients: spectra factor and an electrical parameter which is measured or directly deduced from manufacturer's data. Equivalence for several type of spectra (fission, 14MeV and degradation sensitivity to electrical parameters values of individual components of a batch are obtained.

1974-06-01

149

Forest Carbon Projects: Avoided Deforestation (Hovani)  

Science.gov (United States)

... entitled: In-country Pilot Activities: Reducing Emissions from Deforestation and Degradation)...

152

Transient / Structural Analysis of a Combustor under Explosive Loads  

Science.gov (United States)

Ultimate Compressive Strength = 3000.0 psi. 3.0 Failure Criteria. The structural criteria used to evaluate the combustor components was chosen ...

153

The explosion reason analysis of urea reactor of Pingyin  

British Library Electronic Table of Contents (United Kingdom)

In allusion to the explosion of a urea reactor took place in a fertilizer plant at Pingyin, Shandong, China, a series of evidence collection and inspection jobs which includes collecting operation condition and parameters, sampling the explosion fracture, reactor body apart from explosion fracture, and leak detection medium and its hangover, etc., had been carried out firstly. Based on these jobs, farther analysis and computation work has been done to the structural and materials characteristics and the operation condition of the urea reactor, including compositions, metallographic phases, tensile properties, impact energy, strain ageing characteristics, and fracture toughness of the urea reactor steels, the compositions of leak detection medium and its hangover in the urea reactor, and ex...

2009-01-01

154

The application of a figure of merit for nuclear explosive utility as a metric for material attractiveness in a nuclear material theft scenario  

British Library Electronic Table of Contents (United Kingdom)

Effective integration of nonproliferation management into the design process is key to the broad deployment of advanced nuclear energy systems, and is an explicit goal of the Laser Inertial Fusion Energy (LIFE) project at Lawrence Livermore National Laboratory. The nuclear explosives utility of a nuclear material to a state (proliferator) or sub-state (terrorist) is a critical factor to be assessed and is one aspect of material attractiveness. In this work, we approached nuclear explosives utility through the calculation of a ''figure of merit'' (FOM) that has recently been developed to capture the relative viability and difficulty of constructing nuclear explosives starting from various nuclear material forms and compositions. We discuss the integration of the figure of merit into an asse...

2010-01-01

155

The Landsat Program - Images  

Science.gov (United States)

On April 20, 2010 the Deepwater Horizon offshore drilling rig located in the Gulf of Mexico experienced an explosion resulting in at least 11 deaths and creating ...

156

The Expanded Large Scale Gap Test  

Science.gov (United States)

... an Page 15. NSWC TR 86-32 exploding bridgewire detonator containing PETN rather, than a pri'mary explosive. However ...

1987-03-01

157

Sheep prefer clean forage over forage contaminated with military explosives TNT, RDX and HMX  

British Library Electronic Table of Contents (United Kingdom)

The common military explosives 2-methyl-1,3,5-trinitrobenzene (TNT), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) are distributed in many military training areas, and are thus encountered by grazing animals. The aim of this study was to examine small ruminant's intake of forage contaminated with explosives. An indoor, experimental setup was used to determine if contamination of forage by these compounds affected intake by sheep. The results clearly demonstrate that contamination by any of the three explosives reduced forage intake in sheep; in order of increasing avoidance: RDX

2011-01-01

158

Quantitative Spectroscopy of Photospheric-Phase Type II SN  

Science.gov (United States)

... and high-quality photospheric-phase Type II SN spectra to constrain core- collapse SN explosions, massive star evolution, and distances in the Universe ...

159

Optimal dynamic detection of explosives  

Energy Technology Data Exchange (ETDEWEB)

The detection of explosives is a notoriously difficult problem, especially at stand-off distances, due to their (generally) low vapor pressure, environmental and matrix interferences, and packaging. We are exploring optimal dynamic detection to exploit the best capabilities of recent advances in laser technology and recent discoveries in optimal shaping of laser pulses for control of molecular processes to significantly enhance the standoff detection of explosives. The core of the ODD-Ex technique is the introduction of optimally shaped laser pulses to simultaneously enhance sensitivity of explosives signatures while reducing the influence of noise and the signals from background interferents in the field (increase selectivity). These goals are being addressed by operating in an optimal nonlinear fashion, typically with a single shaped laser pulse inherently containing within it coherently locked control and probe ...

2009-01-01

160

Nanoengineered explosives  

Energy Technology Data Exchange (ETDEWEB)

A complex modulated structure is described for reactive elements that have the capability of considerably more heat than organic explosives while generating a working fluid or gas. The explosive and method of fabricating same involves a plurality of very thin, stacked, multilayer structures, each composed of reactive components, such as aluminum, separated from a less reactive element, such as copper oxide, by a separator material, such as carbon. The separator material not only separates the reactive materials, but it reacts therewith when detonated to generate higher temperatures. The various layers of material, thickness of 10 to 10,000 angstroms, can be deposited by magnetron sputter deposition. The explosive detonates and combusts a high velocity generating a gas, such as CO, and high temperatures. 2 figs.

1996-04-09

161

Minutes of the Third Explosives Safety Seminar on High ...  

Science.gov (United States)

... for. Now there already exists under the SPIA aegis a document which is called the JANAP mailing list. This is the joint Army ...

1961-12-01

162

Lightning Detection for an Air Force Automated Observation ...  

Science.gov (United States)

... of six lightning warning systems was carried out in 1979 as a result of lightning-induced premature explosions in open-pit mining operations. ...

1988-06-08

163

LDRD summary report. Part 1: initiation studies of thin film explosvies used for scabbling concrete. Part 2: investigation of spray techniques for use in explosive scabbling of concrete  

Energy Technology Data Exchange (ETDEWEB)

We describe a new method for the scabbling of concrete surfaces using a thin layer of explosive material sprayed onto the surfaces. We also developed a new explosive mixture that could be applied with commercial spray painting equipment. The first part of our record describes experiments that studied methods for the initiation of the sprayed explosive. We successfully initiated layers 0.36 mm thick using a commercial EBW detonator, a flying plate detonator, and by pellet impact. The second part of our report describes a survey of spray methods and tests with two commercial spray systems that we believe could be used for developing a robotic spray system.

1996-11-01

164

In Situ Seismic Investigation of Folsom Dam and Reservoir ...  

Science.gov (United States)

... An explosive charge (exploding bridgewire (EBW) detonator) was used for the crosshole P-wave tests. For the crosshole S-wave tests a ...

1989-09-01

165

Google Crisis Response: Gulf of Mexico Oil Spill - GCMD - NASA  

Science.gov (United States)

May 13, 2010 ... Abstract: On April 20, 2010, an explosion occurred on the semi-submersible offshore drilling rig Deepwater Horizon in the Gulf of Mexico, ...

166

Fundamental research on explosives  

Energy Technology Data Exchange (ETDEWEB)

The nitric oxide molecule is being studied in order to understand the energetics and chemistry of initiation and detonation in liquid NO at the molecular level. An overview is presented of the work being done. (DLC)

1983-01-01

167

Explosives sensor  

Energy Technology Data Exchange (ETDEWEB)

A compact and supersensitive device that can rapidly detect minute trace vapors from concealed explosives has been developed by scientists at Oak Ridge National Laboratory (ORNL). The new explosives sensor can detect and chemically identify organic nitrogen-oxygen compounds which are the building blocks of explosives such as TNT, plastiques, and nitroglycerine. The device could be used to scan persons entering airport terminals, nuclear power plants, defense installations, or other sensitive locations, providing greater security against potential terrorism. This device works on a glow discharge principle, and is more specifically called an ''Atmospheric Sampling Glow Discharge Ionization'' (ASGDI) source. The new detector is a highly automated, miniaturized version of research mass spectrometers widely used to trace constituents of chemical mixtures. Detail of this device's ...

1987-01-01

168

Creation of the iron-group elements in a supernova explosion  

Energy Technology Data Exchange (ETDEWEB)

The relative abundances of iron-peak elements produced by the e-process in a supernova outburst are calculated. The results agree quite well with the cosmic abundances of elements in the range Z=23--28.

1980-01-01

169

Computer simulation of explosive fracture of oil shale  

Energy Technology Data Exchange (ETDEWEB)

The steps in assembling the computational tools needed to simulate the explosive fracture of oil shale have been described. The resulting code, with its input data, then was used to simulate 3 explosive field experiments. The results of the calculations are in good agreement with what actually occurred in the field. Further detailed comparisons are in progress for these experiments and the others that have been conducted. The development of computer codes as tools to predict rock breakage makes a variety of studies possible. The properties of the explosive can be changed to see how the extent of rubbling is affected. Studies of spacing and delays for decked charges also are possible. The codes can be applied in situations, such as confined-volume blasting, at the frontiers of blasting technology. These areas are vital to the effective utilization of oil shale resources, especially with in situ techniques. 13 references.

1981-01-01

170

Coal industry of South Africa  

Energy Technology Data Exchange (ETDEWEB)

This paper discusses geology, coalfields, coal quality, seams and strata, coal reserves, mining methods, production, coal liquefaction, and research on spontaneous combustion and methane explosions.

1980-06-01

171

Adhesive 'PED-B' for Cementing Plastics of Formula 57-40 to ...  

Science.gov (United States)

... Title : Adhesive 'PED-B' for Cementing Plastics of Formula 57-40 to the Surfaces of Contruction Units,. ... Glue PED-B is not explosive. ...

1964-08-20

172

A Late Holocene explosive mafic eruption of Villarrica volcano, Southern Andes: The Chaimilla deposit  

British Library Electronic Table of Contents (United Kingdom)

Villarrica (Chile) is one of the most active volcanoes in South America having erupted about 60 times in the last 460years. Although its historical eruptive activity has been mainly effusive and weakly explosive, it had strong explosive behaviour in postglacial times. Chaimilla (<3.1ka) is one of the best exposed and widely dispersed pyroclastic deposits, related to both fall and flow activity. The deposit is dispersed over an area of 250km^2 and consists of 8 units (A-H) which were grouped into four sequences. Stratigraphic data suggest that the eruption had a relatively short duration and evolved from i) an Opening phase, dispersing ash, lapilli clasts, accretionary lapilli, blocks and bombs, to ii) a Pulsatory phase, originating a series of magmatic explosions, to iii) a Collapsing phas...

2011-01-01

173

The microbiology of forest soils: a literature review  

Energy Technology Data Exchange (ETDEWEB)

This report discusses the activities of two major groups of forest soil microorganisms, the bacteria and the fungi. Special attention is paid to their participation in the decay of major forest litter substrates, including leaves, branches and roots. The influence of bacteria and fungi in symbiotic associations with woody plant roots upon the cycles of carbon and nitrogen is described. The impacts of certain forest mamagement alternatives are assessed in terms of the creation of elimination of suitable environments for the activity of soil microorganisms. A bibliography is included. 507 refs., 1 tab.

1982-01-01

174

Extended Spectrum ?-Lactamases among Gram-negative bacteria of nosocomial origin from an Intensive Care Unit of a tertiary health facility in Tanzania  

UK PubMed Central (United Kingdom)

BackgroundResistance to third generation cephalosporins due to acquisition and expression of extended spectrum β-lactamase (ESBL) enzymes among Gram-negative bacteria is...Full Text Available

175

Elucidating novel pathways and regulation of nitrogen assimilation in alpha proteobacteria exemplified by the soil organism Paracoccus denitrificans  

Environmental Research Database

DescriptionThe importance of inorganic nitrate for the nutrition and growth of marine and freshwater autotrophic phytoplankton has long been recognised, in particularly because of the 'blooms' formed in nitrate and phosphate polluted water and their possible roles as carbon dioxide sinks. By contrast, the utilisation of nitrate by heterotrophic bacteria has historically received less attention. Up until now, the primary role of heterotrophic bacteria has classically been considered to be the decomposition [continued...

2010-01-31

176

Characteristics of CDC group 1 and group 1-like coryneform bacteria isolated from clinical specimens.  

UK PubMed Central (United Kingdom)

Fifteen strains of CDC group 1 coryneform and biochemically similar bacteria were isolated from clinical specimens. Of the 15 strains isolated, 11 were derived from abscesses and purulent lesions, mostly...Full Text Available

1993-11-01

177

Development and application of microbial selective plugging processes  

Energy Technology Data Exchange (ETDEWEB)

Phillips Petroleum Company recently completed a microbial selective plugging (MSP) pilot at the North Burbank Unit (NBU), Shidler, Oklahoma. Nutrients were selected for the pilot that could stimulate indigenous microflora in the reservoir brine to grow and produce exopolymer. It was found that soluble corn starch polymers (e.g., maltodextrins) stimulated the indigenous bacteria to produce exopolymer, whereas simple sugars (e.g., glucose and sucrose), as well as complex media (e.g., molasses and Nutrient Broth), did not. Injection of maltodextrin into rock cores in the presence of indigenous NBU bacteria resulted in stable permeability reductions (> 90%) across the entire length, while injection of glucose resulted only in face plugging. In addition, it was found that organic phosphate esters (OPE) served as a preferable source of phosphorus for the indigenous bacteria, since orthophosphates and condensed phosphates ...

1995-12-31

178

Repowering and retrofits: building on past value  

Energy Technology Data Exchange (ETDEWEB)

Amidst the explosion of greenfield natural gas-fired combined-cycle plant development, opportunities still exist for valuable plant repowering and retrofits by taking advantages of unique technical and market conditions. One of the projects discussed is the rebuilding of the coal-fired Hawthorne unit 5 damaged by a boiler explosion. 3 tabs., 5 photos.

2000-01-01

179

Realistic Probability Estimates For Destructive Overpressure Events In Heated Center Wing Tanks Of Commercial Jet Aircraft  

Energy Technology Data Exchange (ETDEWEB)

The Federal Aviation Administration (FAA) identified 17 accidents that may have resulted from fuel tank explosions on commercial aircraft from 1959 to 2001. Seven events involved JP 4 or JP 4/Jet A mixtures that are no longer used for commercial aircraft fuel. The remaining 10 events involved Jet A or Jet A1 fuels that are in current use by the commercial aircraft industry. Four fuel tank explosions occurred in center wing tanks (CWTs) where on-board appliances can potentially transfer heat to the tank. These tanks are designated as ''Heated Center Wing Tanks'' (HCWT). Since 1996, the FAA has significantly increased the rate at which it has mandated airworthiness directives (ADs) directed at elimination of ignition sources. This effort includes the adoption, in 2001, of Special Federal Aviation Regulation 88 of 14 CFR part 21 (SFAR 88 ''Fuel Tank System Fault Tolerance Evaluation ...

2007-02-07

180

Monitoring for Xenon Radionuclides and CTBT Verification  

International Nuclear Information System (INIS)

The Comprehensive Nuclear-Test-Ban-Treaty (CTBT), which was opened for signature in 1996, bans all nuclear explosions in all environments. Republic of Korea has been working to monitor compliance with CTBT by deterring and detecting any nuclear explosions conducted anywhere on Earth. For the verification of CTBT, several techniques are implemented. Radionuclide monitoring is of particular importance since it is the only method which can provide absolute assurance that a nuclear detonation has occurred

2010-10-01

181

Explosive acceleration of liquid from a cylindrical container using the implosive technique  

British Library Electronic Table of Contents (United Kingdom)

Tthe acceleration of a liquid from a cylindrical container by the products of instantaneous detonation of a superimposed explosive charge (implosion method) is studies numerically in a two-dimensional formulation. Analytical formulas for the asymptotic velocities of liquid expansion and acceleration of the container body were obtained using numerical calculations in a one-dimensional approximation. The effect of the fracture of the body on the velocity of liquid expansion was studied in a two-dimensional formulation.

2011-01-01

182

Excess transit time as a function of burst current in an exploding bridgewire detonator  

Energy Technology Data Exchange (ETDEWEB)

Transit time, the time from bridgewire burst until breakout of detonation from the output pellet of an exploding bridgewire detonator, was measured as a function of burst current. From this data, in conjunction with known equations for run distance versus pressure, unreacted explosive Hugoniots, and detonation properties of the initial pressing pellet, the run distance in the initial pressing explosive pellet and shock pressure from the exploding bridgewire were determined, both as a function of burst current.

1990-01-01

183

Detection of drugs and explosives using neutron computerized tomography and artificial intelligence techniques  

International Nuclear Information System (INIS)

In this study the development of a methodology to detect illicit drugs and plastic explosives is described with the objective of being applied in the realm of public security. For this end, non-destructive assay with neutrons was used and the technique applied was the real time neutron radiography together with computerized tomography. The system is endowed with automatic responses based upon the application of an artificial intelligence technique. In previous tests using real samples, the system proved capable of identifying 97% of the inspected materials.

2010-06-01

184

Treatment of Difficult Wastes with Molten Salt Oxidation  

Energy Technology Data Exchange (ETDEWEB)

Molten salt oxidation (MSO) is a good alternative to incineration for the treatment of a variety of organic wastes such as explosives, low-level mixed waste streams, PCB contaminated oils, spent resins and carbon. Since mid-1990s, the U.S. Army Defense Ammunition Center (DAC) and the Department of Energy (DOE) have jointly invested in MSO development at the Lawrence Livermore National Laboratory (LLNL). LLNL first demonstrated the MSO process for the effective destruction of explosives, explosives-contaminated materials, and other wastes on a 1.5-kg/hr bench-scale unit, and then in an integrated MSO facility capable of treating 8 kg/hr of low-level radioactive mixed wastes. Several MSO systems have been built with sizes up to 10 ft in height and 16 inches in diameter. LLNL in 2001 completed a MSO plant for DAC for the destruction of explosives-contaminated sludge and ...

2003-02-21

185

Seal Monitoring System for an Explosive Containment Vessel  

Energy Technology Data Exchange (ETDEWEB)

Researchers at Lawrence Livermore National Laboratory are developing high-performance explosive firing vessels to contain (one time) explosive detonations that contain toxic metals and hazardous gases. The filament-wound polymer composite vessels are designed to contain up to 80 lb (TNT equivalent) explosive in a 2-meter sphere without leakage. So far, two half-scale (1-meter diameter) vessels have been tested; one up to 150% of the design explosive limit. Peak dynamic pressures in excess of 280 MPa (40 Ksi) in the vessel were calculated and measured. Results indicated that there was a small amount of gas and particle leakage past the first two of the seven o-ring seals. However, the remaining five seals prevented any transient leakage of the toxic gases and particulates out of the vessel. These results were later confirmed by visual inspection and particulate analysis of swipes taken from the sealing ...

2004-06-28

186

Jet initiation and penetration of explosives  

Energy Technology Data Exchange (ETDEWEB)

The two-dimensional Eulerian hydrodynamic code 2DE, with the shock initiation of heterogeneous explosive burn model called Forest Fire, is used to model numerically the interaction of jets of steel, copper, tantalum, aluminum, and water with steel, water, and explosive targets. The calculated and experimental critical condition for propagating detonation may be described by the Held V/sup 2/d expression (jet velocity squared times the jet diameter). In PBX 9502, jets initiate an overdriven detonation smaller than the critical diameter, which either fails or enlarges to greater than the critical diameter while the overdriven detonation decays to the C-J state. In PBX 9404, the jet initiates a detonation that propagates only if it is maintained by the jet for an interval sufficient to establish a stable curved detonation front. The calculated penetration velocities into explosives, initiated by a low-velocity jet, are ...

1983-01-01

187

Jet initiation and penetration of explosives  

Energy Technology Data Exchange (ETDEWEB)

The two-dimensional Eulerian hydrodynamic code 2DE with the shock initiation of heterogeneous explosive burn model called Forest Fire, is used to model numerically the interaction of jets of steel, copper, tantalum, aluminum, and water with steel, water, and explosive targets. The calculated and experimental critical condition for propagating detonation may be described by the Held V/sup 2/d expression (jet velocity squared times the jet diameter). In PBX 9502, jets initiate an overdriven detonation smaller than the critical diameter, which either fails or enlarges to greater than the critical diameter while the overdriven detonation decays to the C-J state. In PBX 9404, the jet initiates a detonation that propagates only if it is maintained by the jet for an interval sufficient to establish a stable curved detonation front. The calculated penetration velocities into explosives, initiated by a low-velocity jet, are ...

1983-01-01

188

Explosion confinement system for exploitations by sublevels; Sistema de Confinamiento de Explosiones para Explotaciones por Subniveles  

Energy Technology Data Exchange (ETDEWEB)

The objective of this project was to develop a explosion suppression system capable to confine and extinguish gas explosions of the type produced in sub level caving faces when blasting to the coal pillar. Existing systems, such as triggered barriers, were considered not to be valid because of size, weight, cost, and other operational constraints. The research activities have been focused in the development of a mixed water/air spray system that should be manually activated some second before blasting. Two prototypes have been developed and tested, the first one using nozzle operating at the standard ranges of pressure that are normally available in underground coal mines, and a second one based in high-pressure nozzles. In this case, bottles containing a pressurized air/water mixtures are required. The works carried out included theoretical studies, hydraulic nozzles characterization, and modelling of the explosion ...

1999-11-01

189

Comparison of Mount Saint Helens volcanic eruption to a nuclear explosion. Technical note  

Energy Technology Data Exchange (ETDEWEB)

The phenomena and effects of airblast, ground shock, thermal radiation, cratering and ejecta, and debris cloud and deposition from the eruption of Mt. St. Helens were compared to those that would result from a nuclear explosion to determine if phenomena or effects were analogous and thus might provide useful data for military nuclear weapon effects studies. It is concluded that the phenomena are not analogous. In particular, airblast destruction was caused by clouds of ash driven by subsonic winds, rather than by a supersonic shock wave that would be the damage mechanism of a nuclear explosion. Because of the lack of analogy between the eruption and nuclear explosion phenomena, it appears questionable that any of the effects are analogous; therefore, it is unlikely that anything more of military interest can be gained from studying the effects of the eruption. However, key contacts for further information on the eruption ...

1981-01-01

190

Modeling of drug release from bulk-degrading polymers  

British Library Electronic Table of Contents (United Kingdom)

This paper aims to provide a comprehensive review of the various models or simulations for predicting drug release from bulk-degrading systems. A brief description of bulk degradation processes and factors affecting the degradation rate, and consequently the release kinetics, is presented first. Next, several important classical models, often used as the basis for subsequent model development, are discussed. Both mathematical models and Monte-Carlo based simulations have been developed for controlled release from bulk-degrading systems. The mathematical models can be further subdivided into two categories. First, the diffusion-based models whose transport mechanism is mainly governed by diffusion, but with degradation-dependent diffusion coefficients. These are generally simpler and easier...

2011-01-01

191

A comparative study on thermal and catalytic degradation of polybutylene terephthalate  

British Library Electronic Table of Contents (United Kingdom)

A comparative study on the thermal and catalytic degradation of polybutylene terephthalate (PBT) at atmospheric pressure was conducted. The weight loss of PBT under thermal degradation was significantly influenced by the temperature between 360degreeC and 380degreeC, but little affected by the PBT particle size. Four groups of catalysts include metal chloride, metal oxide, metal acetate, and metal copper powder were used to test PBT degradation activity. Copper (II) chloride is the most active one for increasing the percentage PBT weight loss more than 100% in comparison with the result of thermal degradation at a temperature of 360degreeC for 30min. PBT and catalyst mixtures can be prepared by impregnation and physical method, the former resulted in a better PBT degradation. The percentag...

2009-01-01

192

Competitive degradation between the fumigants chloropicrin and 1,3-dichloropropene in unamended and amended soils.  

Science.gov (United States)

The mixture of 1,3-dichloropropene (1,3-D) and chloropicrin (CP) is used as a preplant soil fumigant. In comparison with individual fumigants, application of a mixture may affect the environmental dissipation and fate of each chemical, such as emission and degradation. We investigated the degradation of CP, 1,3-D, and their mixture in fresh soils and sterile soils, and evaluated the competitive characteristic of fumigants in the mixture. The degradation of low concentrations of CP in fresh soil was accelerated at early times in the presence of 1,3-D, whereas the addition of CP reduced the degradation rate of trans-1,3-D, possibly by inhibiting the activity of trans-1,3-D degrading microorganisms. The potential of applying amendments to the soil to increase the rate of CP and 1,3-D degradation was also illustrated. The degradation of both ...

193

Bactericidal effects of non-thermal argon plasma in vitro, in biofilms and in the animal model of infected wounds.  

Science.gov (United States)

Non-thermal (low-temperature) physical plasma is under intensive study as an alternative approach to control superficial wound and skin infections when the effectiveness of chemical agents is weak due to natural pathogen or biofilm resistance. The purpose of this study was to test the individual susceptibility of pathogenic bacteria to non-thermal argon plasma and to measure the effectiveness of plasma treatments against bacteria in biofilms and on wound surfaces. Overall, Gram-negative bacteria were more susceptible to plasma treatment than Gram-positive bacteria. For the Gram-negative bacteria Pseudomonas aeruginosa, Burkholderia cenocepacia and Escherichia coli, there were no survivors among the initial 10(5) c.f.u. after a 5 min plasma treatment. The susceptibility of Gram-positive bacteria was species- and strain-specific. Streptococcus pyogenes was the ...

2010-09-09

194

Oil from coal  

Energy Technology Data Exchange (ETDEWEB)

The conversion of coal to oil can be carried out in two ways. A synthesis route and a degradation route. Each of these routes are described and several degradation processes are explored. The testing of several fuels produced from coal is also given considerations.

1986-06-01

195

Nanostructure and mechanics of mummified type I collagen from the 5300-year-old Tyrolean Iceman  

UK PubMed Central (United Kingdom)

Skin protects the body from pathogens and degradation. Mummified skin in particular is extremely resistant to decomposition. External influences or the action of micro-organisms, however, can degrade...Full Text Available

2010-08-07

196

NOVEL EMBEDDED CERAMIC ELECTRODE SYSTEM TO ACTIVATE NANOSTRUCTURED TITANIUM DIOXIDE FOR DEGRADATION OF MTBE  

Science.gov (United States)

A novel reactor combining a flame-deposited nanostructured titanium dioxide film and a set of embedded ceramic electrodes was designed, developed and tested for degradation of methyl tert-butyl ether (MTBE) in water. On applying a voltage to the ceramic electrodes, a surface coro...

197

Method of restoring degraded solar cells  

Energy Technology Data Exchange (ETDEWEB)

Amorphous silicon solar cells have been shown to have efficiencies which degrade as a result of long exposure to light. Annealing such cells in air at a temperature of about 200.degree. C. for at least 30 minutes restores their efficiency.

1983-01-01

198

Kinetics of chlorinated hydrocarbon degradation by Methylosinus trichosporium OB3b and toxicity of trichloroethylene.  

UK PubMed Central (United Kingdom)

The kinetics of the degradation of trichloroethylene (TCE) and seven other chlorinated aliphatic hydrocarbons by Methylosinus trichosporium OB3b were studied. All experiments were performed with cells...Full Text Available

1991-01-01

199

Effects of pH, Temperature, and Nutrients on Propionate Degradation by a Methanogenic Enrichment Culture  

UK PubMed Central (United Kingdom)

Enrichment cultures were used to determine the conditions promoting fastest methanogenic propionate degradation and growth by adapting the cultures to various physical and chemical conditions and measuring...Full Text Available

1987-07-01

200

Explosive treatment of Illinois No.6 coal with a mixed solvent of water and cyclohexanol; Mizu-cyclohexanol kongo yozai ni yoru Illinois tan no bakusai shori  

Energy Technology Data Exchange (ETDEWEB)

Coal was treated at high temperature under high pressure in the binary system mixed solvent of water and organic solvent, and the solvent treated coal was liquefied. When the treated coal was treated again by the explosive method in which high temperature and pressure were released immediately, the oil yield was higher than that by the normal method in which high temperature and pressure were reduced gradually to room temperature and atmospheric pressure. In this study, an explosive treatment unit with increased scale of sample amount was newly fabricated. Illinois No.6 coal was treated by the explosive method in a mixed solvent of water and cyclohexanol using this unit. Changes in shape on the surface, specific surface area, and functional groups were analyzed. The explosively treated coal contained more amount of low boiling point components than the normally treated coal. It was suggested that the ...

1996-10-28

201

Use of radiosensitivity to identify irradiated fresh poultry products  

International Nuclear Information System (INIS)

Microbiological comparison between irradiated and non-irradiated foodstuff has been studied for a long time as a way to detect whether a foodstuff has been irradiated or not. Generally, the proposed methods are based on the fact that ionization select species of bacteria which are recognized to be radioresistant. So reduction or elimination of known radiation sensitive microbes from the normal endogenous microflora could give an indication that the foodstuff has been irradiated, predominance of known radioresistant bacteria should be another indication. In the present work, we try to develop a test based on the radiosensitivity of the bacteria independently of their place. These first experiments show that the determination of radiosensitivity of strains isolated from a product or even of global radioresistance of mesophilic microflora could indicate if this product has been previously submitted to ionizing radiations. (4 ...

1990-02-14

202

Strength and stability of microbial plugs in porous media  

Energy Technology Data Exchange (ETDEWEB)

Mobility reduction induced by the growth and metabolism of bacteria in high-permeability layers of heterogeneous reservoirs is an economically attractive technique to improve sweep efficiency. This paper describes an experimental study conducted in sandpacks using an injected bacterium to investigate the strength and stability of microbial plugs in porous media. Successful convective transport of bacteria is important for achieving sufficient initial bacteria distribution. The chemotactic and diffusive fluxes are probably not significant even under static conditions. Mobility reduction depends upon the initial cell concentrations and increase in cell mass. For single or multiple static or dynamic growth techniques, permeability reduction was approximately 70% of the original permeability. The stability of these microbial plugs to increases in pressure gradient and changes in cell physiology in a nutrient-depleted ...

1995-12-31

203

PREPARATION AND PROPERTIES OF ANTIBACTERIAL ALGINATE FILMS INCORPORATING EXTRUDED WHITE GINSENG EXTRACT  

British Library Electronic Table of Contents (United Kingdom)

Abstract Preparation of antibacterial alginate films incorporating extruded white ginseng (EWG) extracts was attempted. The antibacterial effect of EWG extract on six selected food pathogenic bacteria was compared with the effect of red ginseng (RG) and white ginseng (WG) extracts. The EWG was processed in a twin-screw extruder with feed moisture of 20% and barrel temperature of 115 and 130C. The data obtained by agar diffusion assay demonstrated that the film containing 1-g/mL of EWG at barrel temperatures of 115 (EWG-115) and 130C (EWG-130) exhibited stronger antibacterial activity against the four strains of bacteria than the other extracts RG and WG. All films sampled showed reduction in bacteria cell counts (log cycle) compared with the control. After 24-h of incubation, Pseudomonas a...

2011-01-01

204

Optimal conditions for stability of photoemission and freeze drying of two luminescent bacteria for use in a biosensor  

British Library Electronic Table of Contents (United Kingdom)

Abstract Bioluminescent bacteria have been used for many years for biotoxicological analysis. One of the main concerns with this microorganism is the low experimental repeatability when subjected to external factors. The aim of the present study was to obtain accurate, sensitive, and repeatable measurements with stable signals (during the detection and over days) for application in a water-analysis device for the detection of pollutants. Growth conditions were tested and optimized. An optimal freeze-drying procedure for the constitutive bioluminescent bacteria Vibrio fischeri and Photobacterium phosphoreum was developed. The luminescence stability after rehydration was also investigated. Freeze drying was found to be a critical process in survival and signal stability of luminescent bacter...

2011-01-01

205

Leaching of zinc sulfide by Thiobacillus ferrooxidans: Bacterial oxidation of the sulfur product layer increases the rate of zinc sulfide dissolution at high concentrations of ferrous ions  

Energy Technology Data Exchange (ETDEWEB)

This paper reports the results of leaching experiments conducted with and without Thiobacillus ferroxidans at the same conditions in solution. The extent of leaching of ZnS with Bacteria is significantly higher than that without bacteria at high concentrations of ferrous ions. A porous layer of elemental sulfur is present on the surfaces of the chemically leached particles, which no sulfur is present on the surfaces of the bacterially leached particles. The analysis of the data using the shrinking-core model shows that the chemical leaching of ZnS is limited by the diffusion of ferrous ions through the sulfur product layer at high concentrations of ferrous ions. The analysis of the data shows that diffusion through the product layer does not limit the rate of dissolution when bacteria are present. This suggests that the action of T.ferroxidans in oxidizing the sulfur formed on the particle surface is to remove the barrier ...

1999-12-01

206

Decolorization of textile azo dyes by newly isolated halophilic and halotolerant bacteria  

British Library Electronic Table of Contents (United Kingdom)

Studies were carried out on the decolorization of textile azo dyes by newly isolated halophilic and halotolerant bacteria. Among the 27 strains of halophilic and halotolerant bacteria isolated from effluents of textile industries, three showed remarkable ability in decolorizing the widely utilized azo dyes. Phenotypic characterization and phylogenetic analysis based on 16S rDNA sequence comparisons indicate that these strains belonged to the genus Halomonas. The three strains were able to decolorize azo dyes in a wide range of NaCl concentration (up to 20%w/v), temperature (25-40degreeC), and pH (5-11) after 4 days of incubation in static culture. They could decolorize the mixture of dyes as well as pure dyes. These strains also readily grew in and decolorized the high concentrations of dy...

2007-01-01

207

Thermal degradation and crystallisation studies of reactively compatibilised polymer blends  

British Library Electronic Table of Contents (United Kingdom)

The thermal degradation and crystallisation behaviours of polyamide12/isotactic polypropylene (PA12/PP) blends were studied. Effects of blend ratio and compatibiliser concentration on the thermal degradation properties of the blends were analysed. The activation energy for degradation in compatibilised and uncompatibilised blends computed using Horowitz-Metzger equation was reported. The blend ratio as well as the presence of compatibiliser has significant effect on the thermal stability of the blends. Phase morphology was found to be one of the decisive factors that affected the thermal stability of both uncompatibilised and compatibilised blends. Melting and crystallisation behaviours of the blends in the presence and absence of compatibiliser were evaluated. It was observed that blendin...

2008-01-01

208

PRODUCTION ENGINEERING MEASURE RELIABILITY ...  

Science.gov (United States)

... without the problem of purple plague. The Au-Ni-In evaporated ... surface and bonding degradation (purple plague) St step-stress ...

1963-09-30

209

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

Energy Technology Data Exchange (ETDEWEB)

The biodegradation of ring-/sup 14/C- and methyl-/sup 14/C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO/sub 2/. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

1985-05-01

210

Mechanism of biodegradation of paraquat by Lipomyces starkeyi  

International Nuclear Information System (INIS)

The biodegradation of ring-"1"4C- and methyl-"1"4C-labeled paraquat by the soil yeast Lipomyces starkeyi was studied in vitro. It was found that the degradation of paraquat (acting as a sole source of culture nitrogen) resulted in the accumulation in the extracellular medium of radiolabeled acetic acid. The culture also evolved radiolabeled CO_2. The results suggest that the degradation of paraquat by L. starkeyi is associated with the integrity of the cell wall and that disruption or removal of the wall results in a complete loss of degradative capability. A mechanism for the degradation of paraquat by this organism is postulated.

211

Electron Beam and Gamma Radiolysis of Solid-State Metoclopramide  

British Library Electronic Table of Contents (United Kingdom)

Purpose Study the radiolysis of solid-state metoclopramide hydrochloride at various absorbed doses. Elucidate the structure of the degradation products to gain information on the radiolysis mechanisms. Methods Solid-state metoclopramide samples were irradiated at several doses with gamma rays and high-energy electrons to evaluate the influence of the dose rate. High-performance liquid chromatography with a diode array detector was used to measure the chemical potency as a function of the absorbed dose and to quantify the degradation products. The characterization of degradation products was performed by liquid chromatography/atmospheric pressure chemical ionization/tandem mass spectrometry. Results The degradation of solid-state metoclopramide after irradiation was negligible. No qualitati...

2006-01-01

212

Accelerated aging tests for radiation degradation of organic materials  

International Nuclear Information System (INIS)

(Jun 1984). United States Clough, RL Gillen, KT Sandia Nat'l Laboratories

1984-06-03

213

Physiological effects of manipulating the level of insulin-degrading enzyme in insulin-producing cells of Drosophila  

UK PubMed Central (United Kingdom)

Insulin-degrading enzyme (IDE) degrades insulin and other peptides, including the Aβ peptide of Alzheimer’s disease. However, the mechanism by which IDE acts on its substrates...Full Text Available

2011-01-01

214

Impact of repeated two-phase olive mill waste application on phosphorus fractionation in a degraded olive grove soil  

Energy Technology Data Exchange (ETDEWEB)

Loss of organic matter is one of the main forms of soil degradation in Mediterranean agricultural soils, and external sources of organic matter are required to improve soil properties. the two-phase centrifugation system in the olive-oil extraction industry produces a large amount of olive mill waste sludge (TPOMW) which can be used to add organic C to degraded soils. (Author)

2009-07-01

215

Video and seismic observations of Strombolian eruptions at Erebus volcano, Antarctica  

British Library Electronic Table of Contents (United Kingdom)

Between 1986 and 1990 the eruptive activity of Erebus volcano was monitored by a video camera with on-screen time code and recorded on video tape. Corresponding seismic and acoustic signals were recorded from a network of 6 geophones and 2 infrasonic microphones. Two hundred Strombolian explosions and three lava flows which were erupted from 7 vents were captured on video. In December 1986 the Strombolian eruptions ejected bombs and ash. In November 1987 large bubble-bursting Strombolian eruptions were observed. The bubbles burst when the bubble walls thinned to ?20?cm. Explosions with bomb flight-times up to 14.5?s were accompanied by seismic signals with our local size estimate, ?unified magnitudes?? (mu), up to 2.3. Explosions in pools of lava formed by flows in the Inner Crater were co...

2008-01-01

216

The response of small scale rigid targets to shallow buried explosive detonations  

British Library Electronic Table of Contents (United Kingdom)

Experimental and computational investigations were performed in order to better understand the mechanical response of rigid targets with various geometries to the detonation of shallow buried explosives. The motion of the targets was measured by use of high-speed digital video photography. This work involved flat targets, targets that were downwardly convex, and targets that were downwardly concave with explosive charges located at various positions beneath the targets. It was observed that, in general, angled hulls - whether downwardly concave or convex - tended to reduce the amount of momentum imparted to the center of mass of the targets. Computations were performed by use of an arbitrary Langrangian-Eulerian treatment in a nonlinear finite element code. A model based on quasi-static te...

2011-01-01

217

Photodestruction of explosives in process water  

Energy Technology Data Exchange (ETDEWEB)

Photodestruction has received much attention in recent years. In particular, titanium dioxide (TiO{sub 2}) and ozonolysis have attained a position of prominence. These technologies hold promise for the destruction of trace amounts of aqueous high explosives that are generated by load and pack operations, as well as demilitarization activities. Currently this water is treated by passing through a bed of activated carbon. The carbon is then steam regenerated and reused, thus creating a second waste stream which must be disposed of, or the carbon is burned directly. Recent trends in environmental regulation have shown that this may not be a viable option for process water remediation in the future. This talk will discuss efforts to employ alternate aqueous treatment techniques that not only remove the explosives compounds but are able to transform the parent compound into carbon dioxide and water. Titanium dioxide photocatalysis as well as ...

1995-12-31

218

Peel-off case failure in thermal explosions observed by the deflagration cylinder test  

British Library Electronic Table of Contents (United Kingdom)

We have discovered a previously unidentified thermal explosion mode using the Los Alamos deflagration cylinder test (DFCT). The DFCT is a "pipe bomb"-style test similar to the detonation cylinder test (DTCT), which has been used for many years to calibrate detonation product equations of state. The shot is heated in an oven to a uniform test temperature. The pre-heated high explosive (HE) is triggered by a hot wire initiator on one end. The tube is back-illuminated by a bright light source, and its combustion-driven deformation and subsequent break-up are observed by a high-speed framing camera. Like the DTCT, the DFCT tube wall motion provides the primary diagnostic. A variety of reactive responses are possible, including quasi-steady deflagration and deflagration-to-detonation transition...

2009-01-01

219

Overheated detonation in condensed explosives  

Energy Technology Data Exchange (ETDEWEB)

The authors examine the overheating of a chemical detonation wave, which results in hybrid detonation processes, for example, photochemical or electrochemical detonation, depending on the source. The schemes for obtaining the overheated detonation are shown. Analysis has shown that: normal stationary overheated detonation waves are possible when the overheating power density is constant, just as when the specific energy of overheating is constant; the use of the ''gas'' equation of state for describing overheated detonation in condensed explosives yields wave parameters which are too high; and the assumption that the chemical energy released in the explosive is independent of the overheating energy also leads to wave parameters which are too high, and the overestimation increases as the overheating is intensified.

1986-03-01

220

Measurement of dynamic fracture toughness and failure behavior for explosive mock materials  

British Library Electronic Table of Contents (United Kingdom)

In this work, a pre-cracked semi-circular shaped explosive simulant was loaded using a split Hopkinson pressure bar (SHPB). A high-speed camera was used to capture the deformation and fracture process of the specimen in situ. The digital images were processed using the digital image correlation (DIC) method. Next, full displacement and strain fields were obtained. The displacement vector field shows that the specimen fractured under tensile stress action. The strain field can be used to predict the crack propagation. Results show that the method of combined DIC and SHPB is effective to study the dynamic deformation and fracture behavior of explosive simulants. In addition, the specimen was loaded using a drop weight. The fracture toughness of the specimen was preliminary measured.

2011-01-01

221

MSHA (Mine Safety and Health Administration) approved mine rescue - training module (coal): fires, fire fighting, and explosions. Mine rescue team series  

Science.gov (United States)

Mine rescue teams frequently must fight fires and guard against the propagation of fires or explosions during a rescue and recovery operation. The team's ability to fight fires depends a great deal on hands-on experience with different fire fighting agents and equipment. The team's work includes an assessment of fire conditions, mine fire gases and other potential hazards associated with fire fighting activity. This training module covers the underlying principles of the fire triangle and the different methods for controlling, containing and extinguishing fires in a mine. The manual also covers fire-fighting equipment, considerations involved in a sealing operation and the cause-effect of explosions.

1984-01-01

222

Formulation of multi-component explosives  

Energy Technology Data Exchange (ETDEWEB)

In a method for formulating a multi-component explosive composition, the steps are described comprising: (a) providing a defined body of unconsolidated particulate aluminum fuel granules having an average particle size within the range of 1/64-1/4 inch and an average bulk density within the range of 0.2-1.0 gm/cc; (b) providing a phase oxidizing liquid; and (c) flooding said body of particulate aluminum fuel of step (a) with the oxidizing liquid of step (b) to provide a bulk density of said mixture of oxidizing liquid and particulate aluminum fuel mass within the range of 1.2-1.7 gm/cc and provide an explosive formulation detonable at 20 C in a diameter of 4 inches by a one pound pentolite booster.

1993-07-13

223

Fire and explosion assessment on oil and gas floating production storage offloading (FPSO): An effective screening and comparison tool  

British Library Electronic Table of Contents (United Kingdom)

Fires and explosions have been identified as major potential hazards for Oil and Gas Floating Production Storage Offloading (FPSO) installations and pose risk to personnel, assets, and the environment. Current fire and explosion assessment (FEA) tools require physical effect modeling software and follows standards from API, ISO, and engineering practices. However, the tools are not specific to any particular system such as an FPSO, and do not provide comprehensive guidance for safety engineers to perform FEA. This paper discusses the development of a screening and comparison tool for FEA on FPSOs and the incorporation of an expert system into the tool. The results are computerized using MS Excel/VBA to provide a structured and comprehensive assessment on each equipment and module handling ...

2009-01-01

224

Explosives detector  

Energy Technology Data Exchange (ETDEWEB)

An apparatus for non-invasively inspecting an object, such as an item of luggage, for explosives material is described. It comprises a multi-channel thermal neutron inspection system having a plurality of neutron irradiation chambers. Simultaneous operation of several channels increases the maximum system throughput several times. Each chamber has a lithium neutron source which is stimulated to neutron production by a proton beam. Beam switching magnets are energised by pulsing to divert a common proton beam to each source in turn. The initial beam is generated by a radio frequency quadrupole accelerator. The advantages of this system are very low residual source activity and controllable neutron production thereby minimising safety hazards. The irradiation chamber may contain several different gamma ray detectors to identify the elements present in explosives material. In addition, a neutron radiography imaging means may be employed to ...

1991-10-02

225

Exploring the Physics of Type Ia Supernovae Through the X-ray Spectra of their Remnants  

CERN Document Server

We present the results of an ongoing project to use the X-ray observations of Type Ia Supernova Remnants to constrain the physical processes involved in Type Ia Supernova explosions. We use the Tycho Supernova Remnant (SN 1572) as a benchmark case, comparing its observed spectrum with models for the X-ray emission from the shocked ejecta generated from different kinds of Type Ia explosions. Both the integrated spectrum of Tycho and the spatial distribution of the Fe and Si emission in the remnant are well reproduced by delayed detonation models with stratified ejecta. All the other Type Ia explosion models fail, including well-mixed deflagrations calculated in three dimensions.

2005-01-01

226

Dismantling by explosives  

Energy Technology Data Exchange (ETDEWEB)

Explosives have rarely been used in decommissioning of nuclear reactors. Nevertheless, controlled blasting can be used advantageously during careful destruction of nuclear power plants for removal of concrete, pipe systems, and other components. Experiments performed within a former nuclear power plant demonstrate the feasibility of this method, employing explosive masses up to 15 kg per blast. The loadings of the components and the total plant structure were measured and compared with code predictions. The experiments show a response of the containment predominantly in frequency ranges above 100 Hz, thus keeping the building and components below German regulation limits for shock excitation. The blast wave pressures are reduced drastically within short distances in the building. Dust and debris can be contained with simple methods such as curtains. Use of this method seems to be applicable to actual dismantling projects.

1989-08-01

227

Comparison of constitutive models for plastic-bonded explosives  

British Library Electronic Table of Contents (United Kingdom)

A constitutive model for an explosive consists of three parts: equation of state of reactants, equation of state of products, and reaction rate. In the absence of a good physical theory, models are empirical and based on heuristics. For the HMX based plastic-bonded explosive PBX 9501, three models have previously been calibrated and used in numerical simulations. Here, these three models are compared. They illustrate several generic difficulties with developing and validating models. The available data is insufficient to determine a constitutive model uniquely. Different models can be calibrated to fit the available data yet differ significantly in regions of phase space of importance to applications. Comparing models gives an indication of the uncertainty in model predictions outside the ...

2008-01-01

228

Vancomycin-resistant Enterococcus domination of intestinal microbiota is enabled by antibiotic treatment in mice and precedes bloodstream invasion in humans  

UK PubMed Central (United Kingdom)

Bloodstream infection by highly antibiotic-resistant bacteria, such as vancomycin-resistant Enterococcus (VRE), is a growing clinical problem that increasingly defies medical intervention....Full Text Available

2010-12-01

229

USGS Water-Quality Information: Fecal Indicator Bacteria  

Science.gov (United States)

USGS - science for a changing world USGS Home Contact USGS Search USGS USGS Water-Quality Information * Home * Data * Methods * Labs * Publications * Topics * Programs * Contact Us...

2011-08-27

230

Type IVB Secretion Systems of Legionella and Other Gram-Negative Bacteria  

UK PubMed Central (United Kingdom)

Type IV secretion systems (T4SSs) play a central role in the pathogenicity of many important pathogens, including Agrobacterium tumefaciens, Helicobacter pylori, and...Full Text Available

231

Toxic Effects of Linear Alkylbenzene Sulfonate on Metabolic Activity, Growth Rate, and Microcolony Formation of Nitrosomonas and Nitrosospira Strains  

UK PubMed Central (United Kingdom)

Strong inhibitory effects of the anionic surfactant linear alkylbenzene sulfonate (LAS) on four strains of autotrophic ammonia-oxidizing bacteria (AOB) are reported. Two Nitrosospira...Full Text Available

2001-06-01

232

The prosthetic group of methanol dehydrogenase. Purification and some of its properties.  

UK PubMed Central (United Kingdom)

Methanol dehydrogenases isolated from bacteria belonging to different classes of methylotrophs contain the same prosthetic group. A procedure for its purification from whole cells is given. The reduced...Full Text Available

1980-04-01

233

The efflux of a fluorescent probe is catalyzed by an ATP-driven extrusion system in Lactococcus lactis.  

UK PubMed Central (United Kingdom)

Many bacteria, both gram positive and gram negative, extrude in an energy-dependent manner the fluorescent pH indicator 2',7'-bis-(2-carboxyethyl)-5[and -6]-carboxyfluorescein (BCECF) (D. Molenaar,...Full Text Available

1992-05-01

234

The control of sulphate reduction in bacteria  

UK PubMed Central (United Kingdom)

1. An enzyme from Escherichia coli 9723 that reduces adenosine 3′-phosphate 5′-sulphatophosphate to inorganic sulphite is described. Extracts of E. coli...Full Text Available

1965-07-01

235

The bacterial signal indole increases epithelial-cell tight-junction resistance and attenuates indicators of inflammation  

UK PubMed Central (United Kingdom)

Interkingdom signaling is established in the gastrointestinal tract in that human hormones trigger responses in bacteria; here, we show that the corollary is true, that a specific bacterial signal,...Full Text Available

2010-01-05

236

The RNA Chaperone Hfq Is Important for Growth and Stress Tolerance in Francisella novicida  

UK PubMed Central (United Kingdom)

The RNA-binding protein Hfq is recognized as an important regulatory factor in a variety of cellular processes, including stress resistance and pathogenesis. Hfq has been shown in several bacteria to...Full Text Available

237

The Pseudomonas aeruginosa PA01 Gene Collection  

UK PubMed Central (United Kingdom)

Pseudomonas aeruginosa, a common inhabitant of soil and water, is an opportunistic pathogen of growing clinical relevance. Its genome, one of the largest among bacteria [5570 open reading...Full Text Available

2004-10-01

238

Surprising Alteration of Antibacterial Activity of 5?-Modified Neomycin against Resistant Bacteria  

UK PubMed Central (United Kingdom)

A facile synthetic protocol for the production of neomycin B derivatives with various modifications at the 5″ position has been developed. Structural activity relationship (SAR) against...Full Text Available

2008-12-11

239

Sulfate Reduction by a Desulfovibrio Species Isolated from Sheep Rumen1  

UK PubMed Central (United Kingdom)

Several dissimilatory, sulfate-reducing bacteria were isolated from the rumen fluid of sheep fed purified diets containing sulfate. One isolate, strain D, was selected for characterization. This organism...Full Text Available

1974-09-01

240

Succession of Indigenous Pseudomonas spp. and Actinomycetes on Barley Roots Affected by the Antagonistic Strain Pseudomonas fluorescens DR54 and the Fungicide Imazalil  

UK PubMed Central (United Kingdom)

In recent years, the interest in the use of bacteria for biological control of plant-pathogenic fungi has increased. We studied the possible side effects of coating barley seeds with the antagonistic...Full Text Available

2001-03-01

241

Structural basis of ligand binding by a c-di-GMP riboswitch  

UK PubMed Central (United Kingdom)

The second messenger signaling molecule bis-(3′-5′)-cyclic dimeric guanosine monophosphate (c-di-GMP) regulates many processes in bacteria, including motility, pathogenesis,...Full Text Available

2009-12-01

242

Sex and space destabilize intransitive competition within and between species  

UK PubMed Central (United Kingdom)

Organisms ranging from bacteria and corals to plants and vertebrates can form intransitive competitive networks, in which coexistence can be maintained because no one species or genotype is superior...Full Text Available

2008-08-22

243

Self-Chaperoning of the Type III Secretion System needle tip proteins IpaD and BipD  

UK PubMed Central (United Kingdom)

Bacteria expressing type III secretion systems (T3SS) have been responsible for the deaths of millions worldwide, acting as key virulence elements in diseases ranging from plague to typhoid...Full Text Available

2007-02-09

244

Reduction of Selenate to Selenide by Sulfate-Respiring Bacteria: Experiments with Cell Suspensions and Estuarine Sediments  

UK PubMed Central (United Kingdom)

Washed cell suspensions of Desulfovibrio desulfuricans subsp. aestuarii were capable of reducing nanomolar levels of selenate to selenide as well as sulfate to sulfide....Full Text Available

1987-06-01

245

Pseudomonas aeruginosa selective adherence to and entry into human endothelial cells.  

UK PubMed Central (United Kingdom)

The pathogenesis of Pseudomonas aeruginosa disseminated infections depends on bacterial interaction with blood vessels. We have hypothesized that in order to traverse the endothelial barrier, bacteria...Full Text Available

1994-12-01

246

Primary structure and regulation of vegetative specific genes of Dictyostelium discoideum.  

UK PubMed Central (United Kingdom)

We have examined the expression and structure of several genes belonging to two classes of vegetative specific genes of the simple eukaryote, Dictyostelium discoideum. In amebae grown on bacteria, deactivation...Full Text Available

1989-12-11

247

Preterm low birthweight and the role of oral bacteria  

UK PubMed Central (United Kingdom)

Preterm and low birthweight (PTLBW) continues to be a major cause of mortality and morbidity across the world. In recent years, maternal periodontal disease has been implicated as a risk factor for...Full Text Available

248

Physiological Adaptation of a Nitrate-Storing Beggiatoa sp. to Diel Cycling in a Phototrophic Hypersaline Mat?  

UK PubMed Central (United Kingdom)

The aim of this study was to investigate the supposed vertical diel migration and the accompanying physiology of Beggiatoa bacteria from hypersaline microbial mats. We combined microsensor,...Full Text Available

2007-11-01

249

PCR-based method for targeting 16S-23S rRNA intergenic spacer regions among Vibrio species  

UK PubMed Central (United Kingdom)

BackgroundThe genus Vibrio is a diverse group of Gram-negative bacteria comprised of 74 species. Furthermore, the genus has and is expected to continue expanding...Full Text Available

250

On Being the Right Size: The Impact of Population Size and Stochastic Effects on the Evolution of Drug Resistance in Hospitals and the Community  

UK PubMed Central (United Kingdom)

The evolution of drug resistant bacteria is a severe public health problem, both in hospitals and in the community. Currently, some countries aim at concentrating highly specialized services in large...Full Text Available

2011-04-01

251

Occurrence of fecal indicator bacteria in surface waters and the subsurface aquifer in Key Largo, Florida.  

UK PubMed Central (United Kingdom)

Sewage waste disposal facilities in the Florida Keys include septic tanks and individual package plants in place of municipal collection facilities in most locations. In Key Largo, both facilities discharge...Full Text Available

1995-06-01

252

Name of Presentation!  

Wastenet

Up-flow anaerobic attached-growth bioreactors filled with pre-treated coir fibres ...coir-fibre arranged in bottle-brush configuration bounded by a novel plastic binding technique ...-three anaerobic filter reactors in series -coir fibre as the bacteria growth media a sedimentation

253

Mutagenic and cytotoxic activity of doxorubicin and daunorubicin derivatives on prokaryotic and eukaryotic cells.  

UK PubMed Central (United Kingdom)

The mutagenic and cytotoxic activity of two newly synthesized doxorubicin derivatives and of one daunorubicin derivative were studied in V79 Chinese hamster cells and bacteria (Salmonella typhimurium...Full Text Available

1984-07-01

254

Molecular biological enhancement of coal biodesulfurization. Final report, October 1988--December 1991  

Energy Technology Data Exchange (ETDEWEB)

The overall objective of this project was to use molecular genetics to develop strains of bacteria with enhanced ability to remove sulfur from coal, and to obtain data that will allow the performance and economics of a coal biodesulfurization process to be predicted. (VC)

1991-12-01

255

Microbial indicators of environmental water pollution. Mizu kankyo ni okeru biseibutsu shihyo  

Energy Technology Data Exchange (ETDEWEB)

Microbial indicators in the environmental water are categorized as follows. 1. Index for pathogenic microbial contamination, especially enteric canal based ones. 2. Index for the ordinary microbial contamination. 3. Index for nutritive assessment. 4. Index for the treating effect of final effluent discharged into an environmental water. 5. Index for distinction of of the contamination source. Above 1 and 2'' are among the indices which cannot be replaced by other physico-chemical substances or indices. Up to the present time, 1'' is assessed by a coliform group and 2'' by the bacteria. Recently, however, the status on the microbial contamination of the environmental water is changing, thus urging the reexamination of the assessment systems. This report describes the following items. Characteristics and the elements of the indices (enteric canal based pathogenic microbial contamination); indices under examination ...

1990-08-10

256

Induction of autolysis in nongrowing Escherichia coli.  

UK PubMed Central (United Kingdom)

Unless relaxation of the stringent response is achieved, all nongrowing bacteria rapidly develop resistance to autolysis induced by a variety of agents, including all classes of cell wall synthesis...Full Text Available

1986-09-01

257

Identification of CTX-M-Type Extended-Spectrum-?-Lactamase Genes Using Real-Time PCR and Pyrosequencing?  

UK PubMed Central (United Kingdom)

CTX-M extended-spectrum β-lactamases (ESBLs) are increasingly prevalent worldwide among Escherichia coli bacteria, mostly in community-acquired urinary tract infections. Finding...Full Text Available

2007-01-01

258

Heavy metals alter the electrokinetic properties of bacteria, yeasts, and clay minerals.  

UK PubMed Central (United Kingdom)

The electrokinetic patterns of four bacterial species (Bacillus subtilis, Bacillus megaterium, Pseudomonas aeruginosa, and Agrobacterium radiobacter), two yeasts (Saccharomyces cerevisiae and Candida...Full Text Available

1992-05-01

259

Gingival crevicular fluid levels of clindamycin compared with its minimal inhibitory concentrations for periodontal bacteria.  

UK PubMed Central (United Kingdom)

Clindamycin concentrations in gingival crevicular fluid and in blood were determined over a 7-h period and were related to the minimal inhibitory concentrations of this agent for 340 bacterial strains...Full Text Available

1981-05-01

260

Generation of Novel Bacterial Regulatory Proteins That Detect Priority Pollutant Phenols  

UK PubMed Central (United Kingdom)

The genetic systems of bacteria that have the ability to use organic pollutants as carbon and energy sources can be adapted to create bacterial biosensors for the detection of industrial pollution....Full Text Available

2000-01-01

261

Evolutionary Trajectories of Beta-Lactamase CTX-M-1 Cluster Enzymes: Predicting Antibiotic Resistance  

UK PubMed Central (United Kingdom)

Extended-spectrum beta-lactamases (ESBL) constitute a key antibiotic-resistance mechanism affecting Gram-negative bacteria, and also an excellent model for studying evolution in real time. A shift in...Full Text Available

2010-01-01

262

Epidemiological Risk Factors for Isolation of Ceftriaxone-Resistant versus -Susceptible Citrobacter freundii in Hospitalized Patients  

UK PubMed Central (United Kingdom)

Antimicrobial resistance is an emerging problem among nosocomial bacteria. Risk factors for the recovery of ceftriaxone-resistant (CRCF) or -susceptible (CSCF) Citrobacter freundii...Full Text Available

2003-09-01

263

Endometrial biopsy in Holstein-Friesian dairy cows. III. Bacteriological analysis and correlations with histological findings.  

UK PubMed Central (United Kingdom)

This study examines the results of bacterial culture from 159 endometrial biopsy samples from 97 commercial dairy cows and correlations between bacteriological and histological findings. Bacteria were...Full Text Available

1991-04-01

264

Endogenous Nitric Oxide Protects Bacteria Against a Wide Spectrum of Antibiotics  

UK PubMed Central (United Kingdom)

Bacterial nitric oxide synthases (bNOS) are present in many Gram-positive species and have been demonstrated to synthesize NO from arginine in vitro and in vivo. However, the physiological role...Full Text Available

2009-09-11

265

Effect of clindamycin on neutrophil killing of gram-negative periodontal bacteria.  

UK PubMed Central (United Kingdom)

Periodontal diseases are infections of the tissues supporting the dentition. Recognition that relatively specific microfloras are associated with distinct clinical forms of periodontal disease has prompted...Full Text Available

1988-10-01

266

Effect of Length of Time before Incorporation on Survival of Pathogenic Bacteria Present in Livestock Wastes Applied to Agricultural Soil  

UK PubMed Central (United Kingdom)

In response to reports that the contamination of food can occur during the on-farm primary phase of food production, we report data that describes a possible cost-effective intervention measure. The...Full Text Available

2004-09-01

267

Dynamics of Microbial Communities on Marine Snow Aggregates: Colonization, Growth, Detachment, and Grazing Mortality of Attached Bacteria  

UK PubMed Central (United Kingdom)

We studied the dynamics of microbial communities attached to model aggregates (4-mm-diameter agar spheres) and the component processes of colonization, detachment, growth, and grazing mortality. Agar...Full Text Available

2003-06-01

268

Distribution Frequency of Pathogenic Bacteria Isolated from Cutaneus Leishmaniasis Lesions  

UK PubMed Central (United Kingdom)

Cutaneous leishmaniasis (CL) is a parasitic disease characterized by single or multiple ulcerations. Secondary bacterial infections are one of the complications that can increase the tissue destruction...Full Text Available

2008-09-01

269

Cyclic Diguanylate Signaling Proteins Control Intracellular Growth of Legionella pneumophila  

UK PubMed Central (United Kingdom)

Proteins that metabolize or bind the nucleotide second messenger cyclic diguanylate regulate a wide variety of important processes in bacteria. These processes include motility, biofilm formation, cell...Full Text Available

270

Critical superparamagnetic/single-domain grain sizes in interacting magnetite particles: implications for magnetosome crystals  

UK PubMed Central (United Kingdom)

Magnetotactic bacteria contain chains of magnetically interacting crystals (magnetosome crystals), which they use for navigation (magnetotaxis). To improve magnetotaxis efficiency, the magnetosome crystals...Full Text Available

2009-12-06

271

Coryneform bacteria in infectious diseases: clinical and laboratory aspects.  

UK PubMed Central (United Kingdom)

Coryneform isolates from clinical specimens frequently cannot be identified by either reference laboratories or research laboratories. Many of these organisms are skin flora that belong to a large number...Full Text Available

1990-07-01

272

Comparison of maintenance energy expenditures and growth yields among several rumen bacteria grown on continuous culture.  

Science.gov (United States)

Maintenance energy expenditures were mesured for five rumen bacteria, Selenomonas ruminantium, Butyrivibrio fibrisolvens, Bacteroides ruminicola, Megasphaera elsdenii, and Streptococcus bovis, by using a complex medium with glucose as the carbon source. Large differences (as high as 8.5-fold) in maintenance energy expenditures were seen among these bacteria. The suggestion is made that maintenance requirements could be a significant determinant of bacterial competition in the rumen. Theoretical maximum growth yields, calculated from double reciprocal plots of yield versus dilution rate, were compared to theoretical Y(ATP) values in order to estimate minimum molar adenosine 5'-triphosphate yields from glucose for each bacterium. Results showed that relative yield among the bacteria was growth rate dependent. At high dilution rates, both S. ruminantium and S. bovis produced lactate as their principal fermentation product. At ...

1979-03-01

273

Comparative in vitro activity of Meropenem, Imipenem and Piperacillin/tazobactam against 1071 clinical isolates using 2 different methods: a French multicentre study  

UK PubMed Central (United Kingdom)

BackgroundMeropenem is a carbapenem that has an excellent activity against many gram-positive and gram-negative aerobic, facultative, and anaerobic bacteria. The major objective...Full Text Available

274

Comparative genomics reveals 104 candidate structured RNAs from bacteria, archaea, and their metagenomes  

UK PubMed Central (United Kingdom)

BackgroundStructured noncoding RNAs perform many functions that are essential for protein synthesis, RNA processing, and gene regulation. Structured RNAs can be detected by comparative...Full Text Available

2010-01-01

275

Community Structure of Ammonia-Oxidizing Bacteria within Anoxic Marine Sediments  

UK PubMed Central (United Kingdom)

The potential for oxidation of ammonia in anoxic marine sediments exists through anaerobic oxidation by Nitrosomonas-like organisms, utilizing nitrogen dioxide, coupling of nitrification,...Full Text Available

2003-03-01

276

Cloning of an insecticidal cholesterol oxidase gene and its expression in bacteria and in plant protoplasts.  

UK PubMed Central (United Kingdom)

We cloned and sequenced structural gene choM, which encodes an insecticidally active cholesterol oxidase in Streptomyces sp. strain A19249. The primary translation product was predicted to be a 547-amino-acid...Full Text Available

1994-12-01

277

Cloning and expression of portions of the 34-kilodalton-protein gene of Mycobacterium paratuberculosis: its application to serological analysis of Johne's disease.  

UK PubMed Central (United Kingdom)

Paratuberculosis (Johne's disease), an endemic mycobacteriosis of cattle that is caused by Mycobacterium paratuberculosis, is characterized by incoercible diarrhea and fecal shedding of bacteria. The...Full Text Available

1993-04-01

278

Chemical and biological monitoring of MIOR on the pilot area of Vyngapour oil field, West Sibera, Russia  

Energy Technology Data Exchange (ETDEWEB)

The pilot area of the Vyngapour oil field allotted for MIOR tests contains three injection and three producing wells. These wells were treated in summer 1993 and 1994. Before, during, and after MIOR treatments on the pilot area the chemical compounds of injected and formation waters were studied, as well as the amount and species of microorganisms entering the stratum with the injected water and indigenous bacteria presented in bottomhole zones of the wells. The results of monitoring showed that the bottomhole zone of the injection well already had biocenosis of heterotrophic, hydrocarbon-oxidizing, methanogenic, and sulfate-reducing bacteria, which were besides permanently introduced into the reservoir during the usual waterflooding. The nutritious composition activated vital functions of all bacterial species presented in the bottomhole zone of the injection well. The formation waters from producing wells showed the increase of the content of ...

1995-12-31

279

Characterization of Airborne Microbial Communities at a High-Elevation Site and Their Potential To Act as Atmospheric Ice Nuclei?  

UK PubMed Central (United Kingdom)

Bacteria and fungi are ubiquitous in the atmosphere. The diversity and abundance of airborne microbes may be strongly influenced by atmospheric conditions or even influence atmospheric conditions themselves...Full Text Available

2009-08-01

280

Changes in Tetracycline Susceptibility of Enteric Bacteria following Switching to Nonmedicated Milk Replacer for Dairy Calves?  

UK PubMed Central (United Kingdom)

A randomized intervention study was conducted to determine if discontinuing use of calf milk replacer medicated with oxytetracycline results in increased tetracycline susceptibility in Salmonella...Full Text Available

2008-06-01

281

Buoyant Densities and Dry-Matter Contents of Microorganisms: Conversion of a Measured Biovolume into Biomass  

UK PubMed Central (United Kingdom)

Several isolates of bacteria and fungi from soil, together with cells released directly from soil, were studied with respect to buoyant density and dry weight. The specific volume (cubic centimeters...Full Text Available

1983-04-01

282

Attachment Stimulates Exopolysaccharide Synthesis by a Bacterium  

UK PubMed Central (United Kingdom)

This study examined the hypothesis that solid surfaces may stimulate attached bacteria to produce exopolymers. Addition of sand to shake-flask cultures seemed to induce exopolymer synthesis by a number...Full Text Available

1993-10-01

283

Association of Nasophyaryngeal Bacterial Colonization during Upper Respiratory Tract Infection and the Development of Acute Otitis Media  

UK PubMed Central (United Kingdom)

Acute Otitis Media occurs mostly after upper respiratory tract infection; the causative bacteria are those colonized in the nasopharynx. We studied 709 URI episodes and found that children with...Full Text Available

2008-02-15

284

Antimicrobial susceptibilities of bacteria associated with periodontal disease.  

UK PubMed Central (United Kingdom)

A total of 193 bacterial strains were tested for their susceptibilities to 14 antimicrobial agents. Penicillin G was active at 2 U/ml against 98% of the oral isolates. Other antibiotics with good activity...Full Text Available

1983-03-01

285

Analysis of the Sulfate-Reducing Bacterial and Methanogenic Archaeal Populations in Contrasting Antarctic Sediments  

UK PubMed Central (United Kingdom)

The distribution and activity of communities of sulfate-reducing bacteria (SRB) and methanogenic archaea in two contrasting Antarctic sediments were investigated. Methanogenesis dominated in freshwater...Full Text Available

2003-06-01

286

Analysis of genomic differences among Clostridium botulinum type A1 strains  

UK PubMed Central (United Kingdom)

BackgroundType A1 Clostridium botulinum strains are a group of Gram-positive, spore-forming anaerobic bacteria that produce a genetically, biochemically, and biophysically...Full Text Available

287

Aggregation Substance Promotes Adherence, Phagocytosis, and Intracellular Survival of Enterococcus faecalis within Human Macrophages and Suppresses Respiratory Burst  

UK PubMed Central (United Kingdom)

The aggregation substance (AS) of Enterococcus faecalis, encoded on sex pheromone plasmids, is a surface-bound glycoprotein that mediates aggregation between bacteria thereby facilitating...Full Text Available

2000-09-01

288

Activity of Four Cephalosporin Antibiotics In Vitro Against Bovine Udder Pathogens and Pathogenic Bacteria Isolated from Newborn Calves  

UK PubMed Central (United Kingdom)

The in vitro activity of chephaloridine, cephalexin, cefatrizine (BL-S640), and cephapirin (BL-P-1322) was evaluated by the serial dilution method against pathogenic gram-positive and gram-negative...Full Text Available

1976-03-01

289

ADP-Glucose Pyrophosphorylase, a Regulatory Enzyme for Bacterial Glycogen Synthesis  

UK PubMed Central (United Kingdom)

The accumulation of α-1,4-polyglucans is an important strategy to cope with transient starvation conditions in the environment. In bacteria and plants, the synthesis of glycogen and starch occurs...Full Text Available

2003-06-01

290

A survey of the sensitivity of fresh clinical isolates to cefuroxime and other antibiotics.  

UK PubMed Central (United Kingdom)

The sensitivities to cefuroxime and cephradine of potentially pathogenic bacteria isolated in two British general hospitals comprising 900 beds have been assessed. In a three-month period 2537 strains...Full Text Available

1979-09-01

291

A small RNA promotes siderophore production through transcriptional and metabolic remodeling  

UK PubMed Central (United Kingdom)

Siderophores are essential factors for iron (Fe) acquisition in bacteria during colonization and infection of eukaryotic hosts, which restrain iron access through iron-binding protein, such as lactoferrin...Full Text Available

2010-08-24

292

A role of ygfZ in the Escherichia coli response to plumbagin challenge  

UK PubMed Central (United Kingdom)

Plumbagin is found in many herbal plants and inhibits the growth of various bacteria. Escherichia coli strains are relatively resistant to this drug. The mechanism of resistance is...Full Text Available

293

Geospatial tools for assessing land degradation in Budgam district, Kashmir Himalaya, India  

British Library Electronic Table of Contents (United Kingdom)

Land degradation reduces the ability of the land to perform many biophysical and chemical functions. The main aim of this study was to determine the status of land degradation in the Budgam area of Kashmir Himalaya using remote sensing and geographic information system. The satellite data together with other geospatial datasets were used to quantify different categories of land degradation. The results were validated in the field and an accuracy of 85% was observed. Land use/land cover of the study area was determined in order to know the effect of land use on the rate of land degradation. Normalized differential vegetation index (NDVI) and slope of the area were determined using LANDSAT-enhanced thematic mapper plus (ETM+) data, advanced space borne thermal emission and reflection radiome...

2011-01-01

294

Degradation Improves Tissue Formation in (Un)Loaded Chondrocyte-laden Hydrogels  

British Library Electronic Table of Contents (United Kingdom)

Background Photopolymerizable poly(ethylene glycol) (PEG) hydrogels offer a platform to deliver cells in vivo and support three-dimensional cell culture but should be designed to degrade in sync with neotissue development and endure the physiologic environment. Questions/purposes We asked whether (1) incorporation of degradation into PEG hydrogels facilitates tissue development comprised of essential cartilage macromolecules; (2) with early loading before pericellular matrix formation, the duration of load affects matrix production; and (3) dynamic loading in general influences macroscopic tissue development. Methods Primary bovine chondrocytes were encapsulated in hydrogels (n?=?3 for each condition). The independent variables were hydrogel degradation (nondegrading PEG and degrading olig...

2011-01-01

295

Rapid preparation of pyrogen-free 2H2(18)O for human-nutrition studies  

International Nuclear Information System (INIS)

We describe a compact ultrafiltration system for the removal of pyrogens and bacteria from water labeled with the stable isotopes of deuterium and oxygen-18. The ultrafiltration system is constructed from readily available commercial components and can achieve complete removal of pyrogens and bacteria from 1L contaminated water within 30 min. By use of our procedure, loss of the isotopically labeled water by retention in the filtration system was minimal. The purified water is suitable for both oral and intravenous administration to healthy human subjects participating in nutrition studies.

296

One-dimensional free boundary problem for actin-based propulsion of Listeria  

Science.gov (United States)

Some bacteria move inside cells by recruiting the actin filaments of the host cells. The filaments are polymerized at the back surface of the bacteria, and they move away, forming a "comet" tail behind the bacterium, which consists of gel network. We develop a one-dimensional mathematical model of the gel based on partial differential equations which involve the number of filaments, the density and velocity of the gel, and the pressure. The two end-points of the gel form two free boundaries. The resulting free boundary problem is rather non-standard. We prove local existence and uniqueness.

2007-04-01

297

Effect of microwaves on microorganisms in foods  

Energy Technology Data Exchange (ETDEWEB)

The microbial safety of foods cooked in microwave ovens was investigated. The mechanisms of microwave destruction of microorganisms were examined. Effects of time and temperature on microorganisms in different food systems were described. Studies showed that: microwave heating of food is more ''''food dependent'' than conventional heating; recommended microwave treatment time for some foods may not destroy high levels of bacteria; use of microwaves in combination with conventional heating methods results in more uniform heating of foods and destruction of bacteria; and microwaves exert different killing effects on individual bacterial species. (78 references, 2 tables)

1980-08-01

298

Characterisation of anti-Staphylococcus aureus activity of quercetin  

British Library Electronic Table of Contents (United Kingdom)

Summary Although many antibiotics are available for the treatment of bacterial infections, the emergence and global spread of antibiotic-resistant bacteria is a community-wide problem. To overcome this problem, we must explore alternative antimicrobials. This study investigated the antibacterial properties of quercetin, a flavonoid present in vegetables and fruits. Quercetin was tested against gram-positive and gram-negative bacteria and was found to exert selective antibacterial activity against Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), and Staphylococcus epidermidis. Some clinical MRSA strains showed remarkable susceptibility to quercetin. In combination with antibiotics, such as oxacillin, ampicillin, vancomycin, gentamicin, and erythromycin, quercetin sho...

2010-01-01

299

Toxicity of N-substituted aromatics to acetoclastic methanogenic activity in granular sludge.  

UK PubMed Central (United Kingdom)

N-substituted aromatics are important priority pollutants entering the environment primarily through anthropogenic activities associated with the industrial production of dyes, explosives, pesticides,...Full Text Available

1995-11-01

300

Terminated Exploding Wire Energy Source.  

Science.gov (United States)

By placing a discharge or 'dump' tube across an exploding bridgewire load, it is possible to by-pass the electrical energy and terminate the explosion of the wire. The dump tube is triggered by a signal derived from the energy removed from the storage cap...

1965-01-01

301

Standardization of rules for manufacturing normal electrical equipment for mining  

Energy Technology Data Exchange (ETDEWEB)

Information is provided about standardization and unification of rules for manufacturing normal electrical equipment designed for operating in underground shafts when there is no danger of explosion of gas, dust or steam. An analysis is made of the requirements included in the CEMA standard and in the state standard.

1983-01-01

302

Possible explosive compounds in the Savannah River Site waste tank farm facilities  

Energy Technology Data Exchange (ETDEWEB)

This report will be revised upon completion of current testing investigating the radiolytic stability of additional energetic materials and the analysis of tank farm samples for volatile and semi-volatile organic compounds.

2000-04-13

303

Oil Leak from Damaged Well in Gulf of ... - NASA Earth Observatory  

Science.gov (United States)

Apr 25, 2010... oil per day were leaking from an oil well in the Gulf of Mexico in late April, following an explosion at an offshore drilling rig on April 20, 2010. ...

304

Near-surface velocity modeling at Yucca Mountain using borehole and surface records from underground nuclear explosions  

International Nuclear Information System (INIS)

The Department of Energy is investigating Yucca Mountain, Nevada as a potential site for commercial radioactive waste disposal in a mined geologic repository. One critical aspect of site suitability is the tectonic stability of the repository site. The levels of risk from both actual fault displacements in the repository block and ground shaking from nearby earthquakes are being examined. In particular, it is necessary to determine the expected level of ground shaking at the repository depth for large seismic sources such as nearby large earthquakes or underground nuclear explosions (UNEs). Earthquakes are expected to cause the largest ground motions at the site, however, only underground nuclear explosion data have been obtained at the repository depth level (about 350m below the ground level) to date. In this study we investigate ground motion from Nevada Test Site underground nuclear explosions recorded at Yucca Mountain ...

2004-02-01

305

Exposure to nitroaromatic explosives and health effects during disposal of military waste  

UK PubMed Central (United Kingdom)

Aims: To investigate the exposure to dinitrotoluene (DNT) and trinitrotoluene (TNT) and the resulting effects in workers which occur during the disposal of military waste. Methods:...Full Text Available

2003-07-01

306

Explosions of chaotic sets  

Science.gov (United States)

Large-scale invariant sets such as chaotic attractors undergo bifurcations as a parameter is varied. These bifurcations include sudden changes in the size and/or type of the set. An explosion is a bifurcation in which new recurrent points suddenly appear at a non-zero distance from any pre-existing recurrent points. We discuss the following. In a generic one-parameter family of dissipative invertible maps of the plane there are only four known mechanisms through which an explosion can occur: (1) a saddle-node bifurcation isolated from other recurrent points, (2) a saddle-node bifurcation embedded in the set of recurrent points, (3) outer homoclinic tangencies, and (4) outer heteroclinic tangencies. (The term ``outer tangency'' refers to a particular configuration of the stable and unstable manifolds at tangency.) In particular, we examine different types of tangencies of stable and unstable manifolds from orbits of pre-existing invariant sets. ...

2000-09-01

307

Energy transfer in solid explosives  

Energy Technology Data Exchange (ETDEWEB)

The nonequilibrium Zeldovich-von Neumann-Doring theory of detonation in solid explosives is extended to include recent nanosecond and picosecond experimental and theoretical results on each of the four main regions of the reaction zone. The first region is the three-dimensional, Mach stem dominated leading shock front which excites the phonon modes of the explosive molecules in less than a picosecond. The second region is the multiphonon up-pumping process in which the excited phonons anharmonically couple to the low frequency (doorway) vibrational modes which in turn equilibrate with the higher frequency modes by internal vibrational redistribution. This process may require on the order of tens of picoseconds. The third region is the chemical reconstitution region in which the vibrationally equilibrated transition state decomposes in a series of chain reaction steps into highly vibrationally excited diatomic and triatomic molecules in ...

1993-07-01

308

Effect of the steam explosion pretreatment on enzymatic hydrolysis of eucalyptus wood and sweet sorghum baggages; Efecto del pretratamiento con explosion por vapor en la hidrolisis enzimatica de madera de eucalipto y bagazo de sorgo  

Energy Technology Data Exchange (ETDEWEB)

The effect of steam explosion treatment on the enzymatic hydrolysis yield of two different lignocellulosic substrates is studied. Raw materials have been pretreated in a pilot plant designed to work in batch and equipped with a reactor vessel of 2 1 working volume where biomass was heated at the desired temperature and then exploded and recovered in a cyclone. Temperatures from 190 to 230 degree celsius and reaction times from 2 to 8 min. have been assayed. The efficiency of the steam explosion treatment has been evaluated on the composition of the lignocellulosic materials as well as on their enzymatic hydrolysis yield using a cellulolytic complex from T. reesel. Results show a high solubilization rate of hemicelluloses and variable losses of cellulose and lignin depending on the conditions tested. Enzymatic hydrolysis yields of both substrates experimented remarkable increments, corresponding the highest values obtained to 210 degree celsius; ...

1991-07-01

309

Computerised, remote monitoring systems for underground coal mines  

Energy Technology Data Exchange (ETDEWEB)

This report presents a study on the use of computerised, continuous remote monitoring systems for fire and explosive atmosphere safety in underground coal mines. The effects of these systems on the safety level in mines are investigated, and the relationship between mine safety regulations and computerised, continuous, remote monitoring is analysed.

1983-03-01

310

Canadian upstream oil and gas industry fire and explosion incident analysis based on the investigative work of the IRP18 Committee working with the University of Calgary Department of Chemical and Petroleum Engineering. Revision 1  

Energy Technology Data Exchange (ETDEWEB)

This report presented an analysis of incidents gathered by the Canadian upstream oil and gas industry committee in relation to explosive atmospheres in wellbores, vessels, tanks, and piping systems. The aim of the report was to develop industry recommended practices for oil and gas industry fires and explosions. Two accident theory models were used to set out the relationships between hazards, defenses, and losses. Three levels of defenses were identified based on organizational, local workplace, and human factors. An organizational responsibility approach was used to examine the activities of key people with the system. Incidents were analyzed based on an expanded fire triangle used to identify fire and explosion hazards. The study showed that the ignition of hydrocarbons into the air was a factor in nearly 50 per cent of the incidents. A lack of understanding of liquid-hydrocarbon properties was demonstrated in incidents ...

2005-05-15

311

Anaesthetic management of post-burn contractures, a recurrent challenge from oil pipeline vandalization in Nigeria: a case report  

UK PubMed Central (United Kingdom)

A 13 year- old girl presented to the department with sternomental contractures as a result of facial burns from kerosene explosion. Difficult airway was envisaged. Over the period of time she developed...Full Text Available

312

A Latent Variable Approach for Meta-Analysis of Gene Expression Data from Multiple Microarray Experiments  

UK PubMed Central (United Kingdom)

BackgroundWith the explosion in data generated using microarray technology by different investigators working on similar experiments, it is of interest to combine results across...Full Text Available

313

1996 Hazardous Substances and New Organisms No. 30  

Wastenet

ii) Flammability: (iii) A capacity to oxidise: (iv) Corrosiveness: (v) Toxicity (including chronic ...an explosion or fire: (d) For substances with corrosive properties: (i) To reduce the ...likelihood of any unintended corrosion:(ii) To control the adverse effects of any corrosion:

314

Study of degradation diagnosis for low voltage cable aged by thermal and radiation with time domain dielectric spectrometer  

International Nuclear Information System (INIS)

Non-destructive methods of diagnosis for detecting cable degradation by aging are being studied recently for improvement of electric wires and cables. This study examines degradation behaviors of cable sheath and insulation by combined accelerated aging tests applying thermal and radiation stresses simultaneously using a typical low voltage cable. According to experiments, elongation of cross-linked polyethylene insulation deteriorated at a faster rate than PVC sheath did under low doses below 50 Gy/h. Therefore, measurements using a time domain dielectric spectrometer (TDS) were carried out for the purpose of developing a method of degradation diagnosis of insulation. It was found that values of tan#delta# measured at very low frequencies below 0.1 Hz increase in pace with degradation of insulation reflecting the level of degradation more effectively than those measured at ...

2000-05-01

315

Degradation mechanisms and accelerated aging test design  

Energy Technology Data Exchange (ETDEWEB)

The fundamental mechanisms underlying the chemical degradation of polymers can change as a function of environmental stress level. When this occurs, it greatly complicates any attempt to use accelerated tests for predicting long-term material degradation behaviors. Understanding how degradation mechanisms can change at different stress levels facilitates both the design and the interpretation of aging tests. Oxidative degradation is a predominant mechanism for many polymers exposed to a variety of different environments in the presence of air, and there are two mechanistic considerations which are widely applicable to material oxidation. One involves a physical process, oxygen diffusion, as a rate-limiting step. This mechanism can predominate at high stress levels. The second is a chemical process, the time-dependent decomposition of peroxide species. This leads to chain branching and can become a ...

1985-01-01

316

Open-pit explosives  

Energy Technology Data Exchange (ETDEWEB)

This paper explains how mine operators are taking a closer look at the power of explosives and how primary breakage affects other open-pit mining costs. Slurries have overcome most of the disadvantages attributed to them in their early years and may replace Anfo. Effective blasting is the key to an efficient, low-cost mining operation. Reviews are presented on research in crater studies, computer-aided design, the expanding gas theory, and high-speed motion picture cameras that show the importance of shock energy in fracturing the rock interfaces throughout the burden. The paper concludes with MSHA-approved courses in blasting offered throughout the US.

1982-07-01

317

On the development of a laser detonator  

Science.gov (United States)

The initiation of explosives by laser illumination has been known for many years. In this paper we will discuss the development of a working detonator design that reduces the energy required for detonation in a low-density secondary explosive by vaporizing a thin metal coating. We present data on the development of the design for a workhorse laser detonator that provides enhanced safety over existing exploding bridgewire detonators (EBWs). Comparison of this laser initiated data to an exploding-bridgewire (EBW) provides insight into the mechanism of initiation of detonation in low-density PETN by the plasma source. A novel diagnostic technique to determine the run-distance to detonation also known as the apparent Center-of-Initiation (COI) will also be discussed.

2005-09-01

318

Nuclear forensics  

International Nuclear Information System (INIS)

Nuclear forensics is the analysis of nuclear materials recovered from either the capture of unused materials, or from the radioactive debris following a nuclear explosion and can contribute significantly to the identification of the sources of the materials and the industrial processes used to obtain them. In the case of an explosion, nuclear forensics can also reconstruct key features of the nuclear device. Nuclear forensic analysis works best in conjunction with other law enforcement, radiological protection dosimetry, traditional forensics, and intelligence work to provide the basis for attributing the materials and/or nuclear device to its originators. Nuclear forensics is a piece of the overall attribution process, not a stand-alone activity

2010-02-01

319

Initiation transient in dilute explosives  

Energy Technology Data Exchange (ETDEWEB)

In the context of the shock-initiation problem, we study analytically the first effects of chemistry, treating a small chemical heat release as a perturbation on an inert flow. Specifically, we study the initial transient in plane-shock initiation in a dilute explosive, where the chemical energy is small relative to the mechanical-thermal energy. The vehicle for the study is the mathematical analog for reactive flow. The solution resembles a double refraction: to first order, the pressure or density is a superposition of two forward-going waves, both originating at the rear boundary, and carrying the same function, but running at different velocities. Surprisingly, this first-order solution is independent of the sensitivity of the reaction rate to the state, which appears only at second order.

1981-01-01

320

Evolution of the white dwarf mass and spin in cataclysmic variables  

International Nuclear Information System (INIS)

We consider the spin-up of the white dwarf in non-magnetic cataclysmic variables (CVs) during secular evolution. If this is unresisted, CVs are quenched as boundary-layer emitters once the binary period has decreased by #approx# 1 hr. Angular momentum loss in nova explosions may, however, prevent the star reaching breakup. If the explosions remove (1 + #epsilon#) x the mass accreted between outbursts, values 0.5 < #approx# #epsilon# < #approx# 1 allow CVs to be modest boundary-layer emitters for most of their lifetimes. Spectral effects will limit their detection as soft X-ray sources. (author).

321

Direct laser initiation of PETN  

Energy Technology Data Exchange (ETDEWEB)

In the early 1970s Yang and Menichelli demonstrated that direct laser illumination of low-density secondary explosive prr:ssings through a transparent window could produce detonation. 'The energy requirement for threshold initiation of detonation was reduced when a thin metal coating of metal covered the side of the window against which the low-density explosive was pressed. We have obtained experimental results that are in general agreement with the results of Renllund, Stanton and Trott (1 989) and recent: work by Nagayama, hou and Nakahara (2001). We report exploration of the effects of laser beam diameter, PEiTN density and specific surface area, and thickness of a titanium coating on the window.

2001-01-01

322

A quantitative method to detect explosives and selected semivolatiles in soil samples by Fourier transform infrared spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a novel Fourier transform infrared (FTIR) spectroscopic method that can be used to rapidly screen soil samples from potentially hazardous waste sites. Samples are heated in a thermal desorption unit and the resultant vapors are collected and analyzed in a long-path gas cell mounted in a FTIR. Laboratory analysis of a soil sample by FTIR takes approximately 10 minutes. This method has been developed to identify and quantify microgram concentrations of explosives in soil samples and is directly applicable to the detection of selected volatile organics, semivolatile organics, and pesticides.

1995-06-01

323

Life evaluation of insulating materials for electric cable by accelerated thermal-radiation combined aging. 2  

International Nuclear Information System (INIS)

Radiation-and-thermal-combined degradation of some kinds of cable insulating and jacketing materials was evaluated by accelerated aging tests. Plasticized polyvinyl chloride (PVC), silicone rubber, crosslinked and non-crosslinked halogen-free flame-retardant polyolefins (NH-XLPO and NH-PO) and ethylene-propylene rubber (EP rubber) of experimental formulation were degraded at accelerated rates, that are 50-1000 times the degradation rate under standard conditions (e.g.; 1Gy/h, 50degC), and a method to assess the lifetime of these materials under standard conditions was studied. The degradation was investigated by measuring tensile properties. In the accelerated aging tests, rates of elongation decrease owing to degradation for these materials were in proportion to the increase in accelerated rate. The PVC lifetime estimated from sequential aging tests had a tendency to extend beyond ...

1994-01-01

324

Stability of model recycled mixed plastic waste compatibilised with a cooperative compatibilisation system  

British Library Electronic Table of Contents (United Kingdom)

The effect of the degree of degradation of the components of a model municipal plastic waste (a mixture of low-density polyethylene, high-density polyethylene, polypropylene and high-impact polystyrene) on the toughness and stability of recyclates compatibilised with a cooperative compatibilisation system (a mixture of ethylene-propylene statistical and styrene-butadiene block copolymers with a secondary amine-based stabiliser) was studied. It was shown that good impact strength was achieved for recyclates having components with a low or medium degree of degradation. Mechanical properties of recyclates having the components with a high degree of degradation are deteriorated. The addition of the cooperative compatibilisation system leads to a higher thermo-oxidative stability of recyclates ...

2011-01-01

325

Resistance of radiation-induced tropical wood-polymer composites to fungal degradation  

Energy Technology Data Exchange (ETDEWEB)

The resistance of six tropical hardwoods to fungal degradation by two wild-type strains of Phanerochaete chrysosporium Burdsall was investigated using vermiculite burial and wood-block weight loss techniques. Radiation-induced wood-polymer composites (WPC), based on two hardwoods Ramin and Rubberwood with methyl methacrylate, were prepared, and samples were also exposed to the wood-rotting fungus. A significant improvement in resistance to fungal decay was observed in the WPC. Scanning-electron micrographs of the two woods and their composites after fungal degradation are presented and discussed.

1987-01-01

326

U.V. repair in deep-sea bacteria  

International Nuclear Information System (INIS)

Exposure of cells to light of less than 320 nanometers wavelengths may lead to lethal lesions and perhaps carcinogenesis. Many organisms have evolved mechanisms to repair U.V. light-induced damage. Organisms such as deep-sea bacteria are presumably never exposed to U.V. light and perhaps occasionally to visible from bioluminescence. Thus, the repair of U.V. damage in deep-sea bacterial DNA might be inefficient and repair by photoreactivation unlikely. The bacteria utilized in this investigation are temperature sensitive and barophilic. Four deep-sea isolates were chosen for this study: PE-36 from 3584 m, CNPT-3 from 5782 m, HS-34 from 5682 m, and MT-41 from 10,476 m, all are from the North Pacific ocean. The deep-sea extends from 1100 m to depths greater than 7000 m. It is a region of relatively uniform conditions. The temperature ranges from 5 to -1"0C. There is no solar light in the deep-sea. Deep-sea bacteria are ...

1986-06-08

327

Interaction of aerobic soil bacteria with plutonium(VI)  

Energy Technology Data Exchange (ETDEWEB)

We studied the interaction of Pu(VI) with Pseudomonas stutzeri ATCC 17588 and Bacillus sphaericus ATCC 14577, representatives of the main aerobic groups of soil bacteria present in the upper soil layers. The accumulation studies have shown that these soil bacteria accumulate high amounts of Pu(VI). The sorption efficiency toward Pu(VI) decreased with increasing biomass concentration due to increased agglomeration of the bacteria resulting in a decreased total surface area and number of available complexing groups. Spores of Bacillus sphaericus showed a higher biosorption than the vegetative cells at low biomass concentration which decreased significantly with increasing biomass concentration. At higher biomass concentrations (> 0.7 g/L), the vegetative cells of both strains and the spores of B. sphaericus showed comparable sorption efficiencies. Investigations on the pH dependency of the biosorption and extraction ...

2000-08-22

328

Improved oil recovery using bacteria isolated from North Sea petroleum reservoirs  

Energy Technology Data Exchange (ETDEWEB)

During secondary oil recovery, water is injected into the formation to sweep out the residual oil. The injected water, however, follows the path of least resistance through the high-permeability zones, leaving oil in the low-permeability zones. Selective plugging of these their zones would divert the waterflood to the residual oil and thus increase the life of the well. Bacteria have been suggested as an alternative plugging agent to the current method of polymer injection. Starved bacteria can penetrate deeply into rock formations where they attach to the rock surfaces, and given the right nutrients can grow and produce exo-polymer, reducing the permeability of these zones. The application of microbial enhanced oil recovery has only been applied to shallow, cool, onshore fields to date. This study has focused on the ability of bacteria to enhance oil recovery offshore in the North Sea, where the environment can be ...

1995-12-31

329

Appendix W: deep sea biophysics (microbiology and amphiped studies)  

International Nuclear Information System (INIS)

CNPT-3 is the laboratory designation of a strain of bacteria that reproduces best at deep-sea pressures. It was isolated from a sample collected at a 5800 m depth of the Pacific Ocean. This isolation was achieved from a sample that had been retrieved without warning. This year we demonstrated that there are similarly behaving bacteria that can be isolated from samples even when retrieved with decompression. The purpose of this project was to define the temperatures and pressures over which CNPT-3 can exist and function. (1) At 2"0C CNPT-3 is eurybathic from about 1000 to 6500 m, as judged from an only slightly pressure dependent generation time. (2) CNPT-3 is unquestionably barophilic at 2"0C, with doubling times of 9 hours at 580 bars and over 18 hours at 1 bar. (3) At 10"0C, reproduction is adversely affected at 1 bar to the extent that CNPT-3 becomes obligately barophilic at 10"0C. Yet reproduction is enhanced above 280 bars and occurs with ...

1981-04-01

330

A study of bacterial isolates from corneal specimens and their antibiotic resistance profile  

International Nuclear Information System (INIS)

We aim to examine the spectrum of bacteria causing corneal infections and their antibiotic susceptibility patterns. This will serve as a guideline for empiric therapy of corneal infections. We conducted the study over a period of 18 months from March 2001 through December 2002 in King Abdul-Aziz University Hospital, Riyadh, Kingdom of Saudi Arabia. Corneal specimens taken from 200 patients were inoculated directly onto different types of media. The isolates were identified and then tested against the appropriate topical or systemic antibiotics. Sixty-seven (33.5%) of the total specimens were culture positive and 133 (66.5%) were culture negative. Fourteen (7%) of these showed organisms in the Gram stained smears and correlated well with the culture reports. Of the 67 positive cultures, 53 (79.1%) were Gram-positive bacteria mostly coagulase-negative Staphylococci 29 (43.3%) followed by Streptococcus pneumoniae (S. pneumoniae) 13 (19.4%). Among ...

331

The multiple roles of autophagy in cancer  

UK PubMed Central (United Kingdom)

Autophagy is an evolutionarily conserved, catabolic process that involves the entrapment of cytoplasmic components within characteristic vesicles for their delivery to and degradation within lysosomes....Full Text Available

2011-07-01

332

The estimation of lifetime distribution of Alloy 800 steam generator tubing  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors worldwide and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under appropriate operating conditions. In planning refurbishment of nuclear plants stations, a key concern is the longevity of existing SGs up to the 60-year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and refines its estimation based on data specific to CANDU operating conditions. The paper presents a more advanced Bayesian probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of ...

2009-10-15

333

The estimation of lifetime distribution of Alloy 800 steam generator tubing  

International Nuclear Information System (INIS)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors worldwide and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under appropriate operating conditions. In planning refurbishment of nuclear plants stations, a key concern is the longevity of existing SGs up to the 60-year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and refines its estimation based on data specific to CANDU operating conditions. The paper presents a more advanced Bayesian probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of ...

2009-10-01

334

Telomeres in cancer and ageing  

UK PubMed Central (United Kingdom)

Telomeres protect the chromosome ends from unscheduled DNA repair and degradation. Telomeres are heterochromatic domains composed of repetitive DNA (TTAGGG repeats) bound to an array of specialized...Full Text Available

2011-01-12

335

Radiosterilization of drugs in aqueous solutions may be achieved by the use of radioprotective excipients  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was to assess the feasibility of radiosterilization of drugs aqueous solutions and to evaluate the effects of some additives, such as mannitol, nicotinamide and pyridoxine, which might protect the drug from degradation. Metoclopramide was selected as a model drug. The structures of the degradation products were determined to gain insight on the radiolysis mechanisms in aqueous solution in order to design strategies to lower the drug degradation.Metoclopramide hydrochloride aqueous solutions with and without excipients were irradiated either with gamma rays or high-energy electrons. HPLC-DAD was used to measure the loss of chemical potency and to quantify the degradation products which were also characterized by LC-APCI-MS-MS. Metoclopramide recovery for gamma and elec...

2008-01-01

336

Pathways for the degradation of organic photovoltaic P3HT:PCBM based devices  

Energy Technology Data Exchange (ETDEWEB)

We report on studies of device degradation in organic photovoltaic devices based on blends of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM). Since delamination, oxidation, and chemical interactions at the metal electrode/organic interface have long been posited as degradation pathways in organic electronic devices, we first investigated the stability of a variety of electrodes for devices stored in an inert, dark environment. Second, a set of experiments was designed to separate the effects at the metal/organic interface from the degradation of the active layer or the hole extraction interface. To do this, Ca/Al electrodes were deposited to complete half of a substrate's devices, and samples were left both under constant illumination and 10% illumination (10% duty cycle of 1 sun illumination) in a glovebox environment. After more than 200 h of measurement, additional electrodes ...

2008-07-15

337

Negative regulation of autophagy  

UK PubMed Central (United Kingdom)

Autophagy is an evolutionarily conserved catabolic process that involves the invagination and degradation of cytoplasmic components through an autophagosomelysosome track. Autophagy functions...Full Text Available

2010-12-01

338

Evaluation of the Influence That Was Produced by Phytoremediation of Soil Microorganisms at Oil Showings  

Science.gov (United States)

Phytoremediation has been identified as a potentially environmentally friendly and cost effective technique for the treatment of contaminated soil. However, phytoremediation has an unknown mechanism. In this study, we focus on the effects of the cultivation of Italian ryegrass on the soil microbes collected at oil showings, which were expected to have a variety of crude oil degradable microorganisms. We evaluated the number of crude oil degradable microorganism, microbial activity, microflora using the PCR-DGGE method and the change in the concentration of crude oil in the soil. The results indicated that the microflora was affected by the cultivation of Itarian ryegrass, and that the microbial activity and the number of crude oil degradable microorganisms were also improved by the cultivation. Moreover, the concentration of crude oil in the rhizosphere soil decreased significantly when compared to the uncultivated soil. ...

2009-01-01

339

DEGRADED TBP SOLVENT REGENERATION TECHNOLOGY USING BUTYLAMINE AS A SOLVENT WASHING TO REDUCE SOLID SALT WASTE  

Energy Technology Data Exchange (ETDEWEB)

Normal butylamine compounds are studied as salt-free wash reagents for degraded solvent used in PUREX process in spent fuel reprocessing. The solvent wash tests were carried out with two types of butylamine compounds, n-butylamine oxalate and n-butylamine bicarbonate, by counter-current mode using a small size mixer-settler composed of two 4-stage wash steps. Di-n-butyl phosphoric acid (HDBP), the main degradation product from TBP, was removed from real degraded solvent with decontamination factor of 2.5 {approx} 7.9. The study on electrolytic decomposition of butylamine compounds was also conducted for waste treatment.

2003-02-27

340

BC  

Wastenet

added to provide resistance to UV degradation, and vulcanization control. ...Sulphur is used to vulcanize the rubber ...additives and solvents age resistors, processing aids, accelerators, vulcanizing agents, softeners and fillers

341

A probabilistic approach to the estimation of lifetime distribution of Alloy 800 SG tubing  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under specified and appropriate operating conditions. In planning refurbishment of CANDU stations, a key concern is the longevity of existing SGs up to the 60 year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and estimates it based on experimental data specific to CANDU operating conditions. The paper presents a more advanced probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of ...

2008-07-01

342

A probabilistic approach to the estimation of lifetime distribution of Alloy 800 SG tubing  

International Nuclear Information System (INIS)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors and in reactors in Germany. Extensive laboratory testing and in-service experience suggest that the Alloy 800 tubing has excellent resistance to corrosion-related degradation under specified and appropriate operating conditions. In planning refurbishment of CANDU stations, a key concern is the longevity of existing SGs up to the 60 year lifetime of the refurbished plant. The paper reviews an existing methodology based on the concept of the improvement factor, and estimates it based on experimental data specific to CANDU operating conditions. The paper presents a more advanced probabilistic approach to estimate the degradation free lifetime distribution of Alloy 800 tubing, which is used to quantify the probability of degradation during the service life and to evaluate the impact of potential occurrences of ...

2008-06-01

343

A feedforward architecture accounts for rapid categorization  

UK PubMed Central (United Kingdom)

Primates are remarkably good at recognizing objects. The level of performance of their visual system and its robustness to image degradations still surpasses the best computer vision systems despite...Full Text Available

2007-04-10

344

9902631 - Lysozyme - NASA  

Science.gov (United States)

Protein isolated from hen egg-white and functions as a bacteriostatic enzyme by degrading bacterial cell walls. First enzyme ever characterized by protein ...

345

1 Title: Historic Emissions from Deforestation and Forest ...  

Science.gov (United States)

on the range of available deforestation, forest degradation, ... Results: Deforestation estimates showed good agreement for multi-year trends of increasing ...

346

Some properties of explosive mixtures containing peroxides  

International Nuclear Information System (INIS)

This study concerns mixtures of triacetone triperoxide (3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexoxonane, TATP) and ammonium nitrate (AN) with added water (W), as the case may be, and dry mixtures of TATP with urea nitrate (UN). Relative performances (RP) of the mixtures and their individual components, relative to TNT, were determined by means of ballistic mortar. The detonation energies, E_0, and detonation velocities, D, were calculated for the mixtures studied by means of the thermodynamic code CHEETAH. Relationships have been found and are discussed between the RP and the E_0 values related to unit volume of gaseous products of detonation of these mixtures. These relationships together with those between RP and oxygen balance values of the mixtures studied indicate different types of participation of AN and UN in the explosive decomposition of the respective mixtures. Dry TATP/UN mixtures exhibit lower RP than analogous mixtures TATP/AN containing up to 25% of ...

2008-06-15

347

Science at the Theater: Hot Technology, Cool Science  

ScienceCinema

...and welcome to ...lab also known as berkeley lab my name is jeff miller and ...and a public affairs i'd like to ? ...but space is science center and ...berkeley albany high school science department and berkeley high school science department and oakland high school science ...be a q. and ...here please use and because we wanna make sure that your questions are here ...heard of also for the latest developments on science and technology ...guy we're going to be any more and more new features i hope ...and change ...thank you ? much and thank you for coming on the welcome to my world of and mayotte science journalist and what i've done for the last almost thirty years ...people about things about which there passionate and national religion tonight and ...people to explain the science and and i asking the question so what ...and ...worldwide and what it does best ? uh ...bench science and turn it into reality what do you scientists and ...uh they take scientific theory and they turn ...

348

Phenotypic characterization of human pathogenic bacteria in fish from the coastal waters of South West Cameroon: public health implications.  

Science.gov (United States)

Increasing economic and recreational opportunities, attractive scenery and a perception of a better quality of life are luring people to the coast. Unfortunately, these activities together with the commensurate increase in population in the area inevitably result in pollution of coastal waters with excessive microorganisms and other pollutants. Microbial pollutants not only contaminate the coastal water but also aquatic food sources, thus posing a health risk to consumers. Fish is a major source of protein in Cameroon, especially in the coastal areas. In this study, we investigated the microbiological quality of fish from the Limbe and Tiko beaches in South West Cameroon from May to October 2007. We isolated human pathogenic bacteria from three anatomic sites (skin, gills, intestine) of 50 fish (150 specimens) and investigated their susceptibility patterns to a battery of antibiotics. Data were analyzed statistically using chi2 with significance set at p South West ...

349

Mine drainage treatment; Kogyo haisui shori  

Energy Technology Data Exchange (ETDEWEB)

The generation of acidic mine drainage is based on the oxidation dissolution of sulfide minerals due to the contact of ores with the natural water and the air. Namely, the sulfuric acid promotes the dissolution of sulfide minerals and gangue minerals, and Fe{sup 2+} is further oxidized to turn into Fe{sup 3+}, which acts as an oxidizer for other sulfide minerals and promotes the dissolution of the same. This paper roughly describes a mine drainage treatment focusing on an Fe{sup 2+} neutralization method and an iron bacteria oxidation method. The iron bacteria oxidation method is a method of oxidizing Fe{sup 2+} into Fe{sup 3+} by using iron bacteria, and then removing Fe{sup 3+} with calcium carbonate. This method has been used for treating the drainage in the Sakuhara Mine and the former Matsuo Mine, with good results. The paper finally introduces, as power-saving low-cost mine drainage treatment methods, a method of ...

1996-05-25

350

Identification of culturable and originally non-culturable endophytic bacteria isolated from shoot tip cultures of banana cv. Grand Naine  

British Library Electronic Table of Contents (United Kingdom)

In this article we describe the identification of endophytic bacteria belonging to three groups isolated from shoot tip cultures of banana cv. Grand Naine in a recent study (Thomas et?al. 2008) based on partial 16S rRNA gene sequence homology analysis. The first group included banana stocks that displayed obvious colony growth on MS based tissue culture medium during the first in?vitro passage. The second group constituted stocks that were tissue index-negative for cultivable bacteria initially but turned index-positive after a few to several (4?8) in?vitro passages while the third group formed one sub-stock that turned index-positive after about 18 passages. The organisms belonged to about 20 different genera comprising of ?, ?, ?-proteobacteria, Gram-positive firmicutes and actinobacteri...

2008-01-01

351

Growth and reproduction of nematodes isolated from tap water; Suidosui kara bunrisareta senchurui no zoshoku tokusei  

Energy Technology Data Exchange (ETDEWEB)

This paper elucidates morphological characteristics, reproduction forms and ecological characteristics of Plectus sp. and Rhabditis sp. which are most frequently detected nematodes separated from tap water. The paper also discussed experimentally establishment of cultivating conditions for these nematodes, and behavior and reproduction characteristics of nematodes under widely ranging conditions of temperatures, bacteria concentrations and pH. Plectus sp. grows in hermaphroditic individuals, while Rhabditis sp. grows only in female. An LE culture medium can cultivate nematodes that appear in tap water, and is suitable for subculture of nematodes. Conditions of temperatures from 20{degree}C to 25{degree}C, pH and inoculated concentration of bacteria at 10{sup 8} cell {center_dot} ml{sup -1} are suitable for reproduction of Plectus sp. and Rhabditis sp. Plectus sp. and Rhabditis sp. prefer mild temperatures for reproduction, cannot reproduce ...

1996-08-10

352

Effects of microwaves on cell survival at elevated temperatures  

Energy Technology Data Exchange (ETDEWEB)

Since microwaves are used in human cancer therapy, information on specific biological effects of microwaves at elevated temperatures is important. To help supply this information, we exposed mammalian cells (CHO) and bacteria (Serratia marcescens) to hyperthermal temperatures (43, 44, and 45/sup o/C for CHO and 48, 49, and 50/sup o/C for the bacteria) with and without microwave irradiation. Temperature control was maintained by a refrigeration-reheat system and high-velocity water recirculation. The 2450-MHz microwave source was operated in a pulsed mode with power density up to 500 mW/cm/sup 2/. As expected, the survival curve slopes for both cell types increased rapidly with temperature, doubling for each degree Celsius. Microwave irradiation produced no significant change in extrapolation number for either cell type. However, survival curves of CHO cells which received microwaves were steeper by a factor of 1.25 than their sham-irradiated ...

1981-12-01

353

Biocatalytic desulfurization of petroleum and middle distillates  

Energy Technology Data Exchange (ETDEWEB)

Biocatalytic Desulfurization (BDS) represents an alternative approach to the reduction of sulfur in fossil fuels. The objective is to use bacteria to selectively remove sulfur from petroleum and middle distillate fractions, without the concomitant release of carbon. Recently, bacteria have been developed which have the ability to desulfurize dibenzothiophene (DBT) and other organosulfur molecules. These bacteria are being developed for use in a biocatalyst-based desulfurization process. Analysis of preliminary conceptual engineering designs has shown that this process has the potential to complement conventional technology as a method to temper the sulfur levels in crude oil, or remove the recalcitrant sulfur in middle distillates to achieve the deep desulfurization mandated by State and Federal regulations. This paper describes the results of initial feasibility studies, sensitivity analyses and conceptual design work. ...

1993-02-01

354

Use of explosive quick depressurization valves in the SBWR project. Dynamic loads induced by their operation  

International Nuclear Information System (INIS)

In General Electric's design of the Simplified Boiling Water Reactor (SBWR), The depressurization valves (DPV) are installed in the reactor pressure boundary: four are connected to the reactor vessel by means of nozzles, and two more are located on the main steam pipes (one DPV for each line), which act during particular transients and/or loss of coolant accidents (LOCA), consequently providing the reactor vessel with a safe quick depressurization system. Once the vessel is de pressurised, the passive gravity-driven cooling system (GDCS) starts to operate, permitting the injection of water required for continuous core cooling. DPVs are leak tight, with welded flaps, actuated by a [striker[hammer***] which is activated by an explosive mixture. The dynamic loads that open these valves include, in addition to those produced by steam (typical in any thermodynamic transient with open/close valves), other important loads that are characteristic of this type of ...

355

Theoretical Support for the Hydrodynamic Mechanism of Pulsar Kicks  

CERN Document Server

The collapse of a massive star's core, followed by a neutrino-driven, asymmetric supernova explosion, can naturally lead to pulsar recoils and neutron star kicks. Here, we present a two-dimensional, radiation-hydrodynamic simulation in which core collapse leads to significant acceleration of a fully-formed, nascent neutron star (NS) via an induced, neutrino-driven explosion. During the explosion, a ~10% anisotropy in the low-mass, high-velocity ejecta lead to recoil of the high-mass neutron star. At the end of our simulation, the NS has achieved a velocity of ~150 km s$^{-1}$ and is accelerating at ~350 km s$^{-2}$, but has yet to reach the ballistic regime. The recoil is due almost entirely to hydrodynamical processes, with anisotropic neutrino emission contributing less than 2% to the overall kick magnitude. Since the observed distribution of neutron star kick velocities peaks at ~300-400 km s$^{-1}$, recoil due to ...

2010-01-01

356

Plane Shock Generator Explosive Lens: Shock characterization of 4340 and PH13-8Mo steels, C360 brass and PZT 65/35 ferro-electric ceramic  

Energy Technology Data Exchange (ETDEWEB)

Sandia National Laboratories is currently involved in the optimization of a Plane Shock Generator Explosive Lens (PSGEL). The PSGEL component consists of a detonator, explosive, brass cone and tamper housing. The purpose of the PSGEL component is to transmit a plane shock wave through the 4340 steel bulkhead (wave separator) which has a ferro-electric (PZT)ceramic disk attached to the opposite surface of the steel bulkhead. The planar shock wave depolarizes the PZT 65/35 ferro-electric ceramic to produce an electrical output. One aspect of the optimization program involves the possible replacement of 4340 steel with PH13-8Mo steel for the bulkhead. These materials, as well as the PZT 65/35 ferro-electric ceramic and the brass for the cone, required the stock characterization with respect to Hugoniot parameters. The work presented here gives the shock Hugoniot values for these four materials and documents their measurements.

1994-03-01

357

Evaluating Systematic Dependencies of Type Ia Supernovae: The Influence of Progenitor Ne22 Content on Dynamics  

CERN Document Server

We present a theoretical framework for formal study of systematic effects in Supernovae Type Ia (SN Ia) that utilizes 2-d simulations to implement a form of the deflagration-detonation transition (DDT) explosion scenario. The framework is developed from a randomized initial condition that leads to a sample of simulated SN Ia whose Ni56 masses have a similar average and range to those observed, and have many other modestly realistic features such as the velocity extent of intermediate mass elements. The intended purpose is to enable statistically well-defined studies of both physical and theoretical parameters of the SN Ia explosion simulation. We present here a thorough description of the outcome of the SN Ia explosions produced by our current simulations. A first application of this framework is utilized to study the dependence of the SN Ia on the Ne22 content, which is known to be directly influenced by the progenitor ...

2009-01-01

358

Continuation application for the Amarillo National Resource Center for Plutonium, a higher education consortium consisting of Texas A and M University, Texas Tech University, and the University of Texas at Austin  

Energy Technology Data Exchange (ETDEWEB)

This report describes the 5 tasks to be covered under this project and compiles budget information. Task 1 is to establish a Plutonium Information Resource, which has been established in Amarillo, Texas. Task 2, Advisory Functions, coordinates studies and activities relating to the disposition of excess weapons-grade plutonium. Task 3, Environmental, Public Health, and Safety, supports soil remediation activities. Task 4, Education and Outreach, is supporting four programs: K--12 education improvement in science and math courses; Academic intervention to identify and encourage high ability high school and middle school students with potential to become scientists and engineers; Graduate education evaluation; and Public outreach programs. Task 5, Plutonium and other Materials Studies, is currently funding two projects for the disposition of high explosives: a feasibility study of burning a mixture of high explosives and other materials in a ...

1995-06-29

359

Are HI Supershells the Remnants of $\\gamma$-Ray Bursts?  

CERN Document Server

Gamma-Ray Bursts (GRBs) are thought to originate at cosmological distances from the most powerful explosions in the Universe. If GRBs are not beamed then the distribution of their number as a function of gamma-ray flux implies that they occur once per (0.3-40) million years per bright galaxy and that they deposit >10^{53} ergs into their surrounding interstellar medium. The blast wave generated by a GRB explosion would be washed out by interstellar turbulence only after tens of millions of years when it finally slows down to a velocity of 10 km/s. This rather long lifetime implies that there could be up to several tens of active GRB remnants in each galaxy at any given time. For many years, radio observations have revealed the enigmatic presence of expanding neutral-hydrogen (HI) supershells of kpc radius in the Milky Way and in other nearby galaxies. The properties of some supershells cannot be easily explained in terms of conventional ...

1998-01-01

360

Synergistic interaction of eugenol with antibiotics against Gram negative bacteria  

British Library Electronic Table of Contents (United Kingdom)

Eugenol, the principal chemical component of clove oil from Eugenia aromatica has been long known for its analgesic, local anesthetic, anti-inflammatory, and antibacterial effects. The interaction of the eugenol with ten different hydrophobic and hydrophilic antibiotics was studied against five different Gram negative bacteria. The MIC of the combination was found to decrease by a factor of 5-1000 with respect to their individual MIC. This synergy is because of the membrane damaging nature of eugenol, where 1mM of its concentration is able to damage nearly 50% of the bacterial membrane. Eugenol was also able to enhance the activities of lysozyme, Triton X-100 and SDS in damaging the bacterial cell membrane. The hydrophilic antibiotics such as vancomycin and b-lactam antibiotics which have ...

2009-01-01

361

Responses of Bark Beetle-Associated Bacteria to Host Monoterpenes and Their Relationship to Insect Life Histories  

British Library Electronic Table of Contents (United Kingdom)

Bark beetles that colonize living conifers and their microbial associates encounter constitutive and induced chemical defenses of their host. Monoterpene hydrocarbons comprise a major component of these allelochemicals, and many are antibiotic to insects, fungi, and bacteria. Some bark beetle species exhaust these defenses by killing their host through mass attacks mediated by aggregation pheromones. Others lack adult aggregation pheromones and do not engage in pheromone-mediated mass attacks, but rather have the ability to complete development within live hosts. In the former species, the larvae develop in tissue largely depleted of host terpenes, whereas in the latter exposure to these compounds persists throughout development. A substantial literature exists on how monoterpenes affect b...

2011-01-01

362

Pit lakes: their characteristics and the potential for their remediation  

Energy Technology Data Exchange (ETDEWEB)

Pit lakes form when open-pit mining operations are discontinued and dewatering ceases. The increase in open-pit metal mining since the 1970s will lead to the formation of numerous pit lakes over the next 50 years. Many of these lakes will develop acid sulfate conditions with high levels of dissolved metals. Approaches to remediation of these conditions that have been recommended include the addition of lime or other alkaline materials and the stimulation of sulfate-reducing bacteria. However, prevention rather than remediation is probably the preferable approach. Measures to prevent oxidation of mining waste and wall rocks, including measures to fill pits quickly with water, to inhibit the activity of acidophilic sulfur-oxidizing bacteria, and to promote anoxic conditions at the lake bottoms may minimize the formation of acids and dissolved metals. (orig.)

2000-10-01

363

In vitro competitive adhesion and production of antagonistic compounds by lactic acid bacteria against fish pathogens  

British Library Electronic Table of Contents (United Kingdom)

The present study describes the screening of five lactic acid bacteria (LAB) for use as probiotics based on their competitive adhesion and production of antagonistic substances against some fish pathogens. A reduction of adhesion of all pathogenic strains tested was obtained with three of the LAB strains (Lactococcus lactis subsp. lactis CLFP100, Lactococcus lactis subsp. cremoris CLFP102 and Lactobacillus curvatus CLFP150). With the exception of fish pathogens Flavobacterium psychrophilum and Renibacterium salmoninarum that were not inhibited by LAB strains, production of antagonistic compounds by all tested LAB was observed against at least one of the indicator strains. Based on mucus adhesion, competitive exclusion, and suppression of fish pathogen growth, the selected LAB strains can b...

2007-01-01

364

Immobilization of bacteria in microgel grafted onto macroporous polyethylene  

Energy Technology Data Exchange (ETDEWEB)

The development of 'Green Chemistry' requires new materials to replace the conventional organic chemistry by biological catalysts, to produce fine chemicals in an environmentally friendly manner. Microbial whole cells can be directly used as biocatalysts, providing a simple and cheap methodology since enzyme isolation and purification are avoided. High-density polyethylene (HDPE) is a very stable polymer though it can be activated by gamma radiation to induce grafting. Glycidyl methacrylate was grafted onto macroporous HDPE and PP in the range of 1-6%, proportional to the initial monomer concentration. Grafted polymers were further chemically modified with ethylenediamine to generate a cationic hydrogel of micron-size thickness onto the internal polymer surfaces. Modified polymers were able to immobilize Gram-positive and Gram-negative bacteria that can catalyze a chemical reaction as efficient as free cells do.

2010-03-15

365

Food-grade gene expression in lactic acid bacteria  

British Library Electronic Table of Contents (United Kingdom)

Abstract In the 1990s, significant efforts were invested in the research and development of food-grade expression systems in lactic acid bacteria (LAB). At this time, Lactococcus lactis in particular was demonstrated to be an ideal cell factory for the food-grade production of recombinant proteins. Steady progress has since been made in research on LAB, including Lactococcus, Lactobacillus and Streptococcus, in the areas of recombinant enzyme production, industrial food fermentation, and gene and metabolic pathway regulation. Over the past decade, this work has also led to new approaches on chromosomal integration vectors and host/vector systems. These newly constructed food-grade gene expression systems were designed with specific attention to self-cloning strategies, food-grade selection...

2011-01-01

366

Electrochemistry of a semiconductor chalcopyrite concentrate leaching by Thiobacillus ferrooxidans  

Energy Technology Data Exchange (ETDEWEB)

Using carbon-paste-CuFeS{sub 2} electrodes and a cyclic voltammetric technique, it was found that a large number of intermediate electrochemical oxidation reactions were associated with the dissolution of chalcopyrite in presence and absence of bacteria. The effects of concentrations of copper, ferrous and ferric ions, as well as of agitation on the peaks of cyclic voltammograms were measured. It was established that chalcopyrite oxidation was solid-state controlled as suggested by the data of chronopotentiometric and chronoamperometric measurements. The activation energy of solid state diffusion of chalcopyrite leaching was determined by the Sand's method to be {triangle}E{sub a} = 20.5 kJ. The leaching mechanism is discussed in terms of solid-state properties (energy bonding) of the n-type semiconductor chalcopyrite and energy density states of redox systems of acidic bacterial leach media. A generalized model for the mechanism of chalcopyrite leaching ...

1991-01-01

367

Efficacy of three commercially available ballast water biocides against vegetative microalgae, dinoflagellate cysts and bacteria  

British Library Electronic Table of Contents (United Kingdom)

One proposed solution to the problem of ballast-mediated aquatic invasions involves chemically treating ballast water to kill key target organisms. Here, we examine the efficacy of three commercially available ballast water biocides using vegetative microalgae, dinoflagellate resting cysts and bacteria as test organisms. Chemicals tested were the ballast water biocides SeaKleen and Peraclean Ocean, and the chlorine dioxide biocide Vibrex. Results demonstrate that the applicability of each of the three chemical biocides as a routine ballast water treatment is limited by factors such as cost, biological effectiveness and possible residual toxicity of the discharged ballast water (assessed on the basis of impact on motility of vegetative marine microalgae). Of the three biocides tested, Perac...

2007-01-01

368

Comparative activity of tigecycline and tetracycline on Gram-negative and Gram-positive bacteria revealed by a multicentre study in four North European countries  

British Library Electronic Table of Contents (United Kingdom)

Abstract Background: This study involves a multicentre surveillance of tigecycline and tetracycline activity against Gram-negative and Gram-positive bacteria from primary care centres (PCCs), general hospital wards (GHWs) and intensive care units (ICUs) in Denmark (n == 9), Finland (n == 10), Norway (n == 7) and Sweden (n == 19). Methods: The hospitals were each asked to test 30 consecutive Gram-positive and 30 Gram-negative clinical isolates. Supportive information accompanying each isolate included the study centre, ward level (PCC, GHW, or ICU), patient identification and source of the isolate. Minimum inhibitory concentrations (MICs) for tetracycline and tigecycline were determined with the Etest. Results: The isolates collected comprised 1610 Gram-negative and 1767 Gram-positive clini...

2011-01-01

369

Antimicrobial silver-montmorillonite nanoparticles to prolong the shelf life of fresh fruit salad  

British Library Electronic Table of Contents (United Kingdom)

In this work, silver-montmorillonite (Ag-MMT) antimicrobial nanoparticles have been obtained by allowing silver ions from nitrate solutions to replace the Na^+ of natural montmorillonite and then to be reduced by a thermal treatment. Ag-MMT were used as active antimicrobial compounds to improve the shelf life of fresh fruit salad. In order to assess their influence on product shelf life, sensorial and microbiological quality has been monitored during the storage. The microbiological quality was determined by monitoring the principal spoilage microorganisms (mesophilic and psychrotrophic bacteria, coliforms, lactic acid bacteria, yeasts and molds). Additionally, the evolution of sensorial quality was assessed by monitoring color, odor, firmness and product overall quality. The Ag-MMT nanopa...

2011-01-01

370

A lytic enzyme cocktail from Streptomyces sp. B578 for the control of lactic and acetic acid bacteria in wine  

British Library Electronic Table of Contents (United Kingdom)

Beside yeasts, lactic acid bacteria (LAB) are the most abundant microbes in must during vinification. Whereas Oenococcos oeni is commercially used as a starter culture for the biological acid reduction in wines, other species are responsible for different types of wine spoilage. Members of the genera Pediococcus, Weissella, Leuconostoc, and Lactobacillus are producers of exopolysaccharide slimes, biogenic amines, acetic acid, and other off-flavors. In order to control microbial growth, different procedures such as heating of must and addition of sulfite or lysozyme from egg white are generally applied. Yet, because of health risks, the application of sulfite should be reduced and lysozyme is not effective against all LAB. In this study, we describe exoenzymes from a Streptomyces sp. strain...

2009-01-01

371

Two Different Types of Dehalogenases, LinA and LinB, Involved in ?-Hexachlorocyclohexane Degradation in Sphingomonas paucimobilis UT26 Are Localized in the Periplasmic Space without Molecular Processing  

UK PubMed Central (United Kingdom)

γ-Hexachlorocyclohexane (γ-HCH) is one of several highly chlorinated insecticides that cause serious environmental problems. The cellular proteins of a γ-HCH-degrading bacterium,...Full Text Available

1999-09-01

372

Thermochemical alkaline degradation of polysaccharide materials: Product characterization and identification  

Energy Technology Data Exchange (ETDEWEB)

Degradation of cellulosics or starch in alkaline solution produces mostly organic acids which are monocarboxylic in nature. Seven of the organic acids have been identified as formic, acetic, glycolic, lactic, 2-hydroxybutyric, 2-hydroxyisobutyric and 2-hydroxyvaleric acids. In total, their yields amount to 41-46% of starting material weight.

1985-01-01

373

Signal transduction pathway controlling synthesis of a class of degradative enzymes in Bacillus subtilis: expression of the regulatory genes and analysis of mutations in degS and degU.  

UK PubMed Central (United Kingdom)

The rates of synthesis of a class of both secreted and intracellular degradative enzymes in Bacillus subtilis are controlled by a signal transduction pathway defined by at least four regulatory genes:...Full Text Available

1990-02-01

374

Organization of lin Genes and IS6100 among Different Strains of Hexachlorocyclohexane-Degrading Sphingomonas paucimobilis: Evidence for Horizontal Gene Transfer  

UK PubMed Central (United Kingdom)

The organization of lin genes and IS6100 was studied in three strains of Sphingomonas paucimobilis (B90A, Sp+, and UT26) which degraded hexachlorocyclohexane...Full Text Available

2004-04-01

375

Low concentrations of primaquine inhibit degradation but not receptor-mediated endocytosis of asialoorosomucoid by HepG2 cells  

Energy Technology Data Exchange (ETDEWEB)

Asialoorosomucoid (ASOR) is internalized and degraded by HepG2 cells after binding to the asialoglycoprotein (ASGP) receptor, internalization through the coated pit/coated vesicle pathway, and trafficking to lysosomes. Primaquine, an 8-aminoquinoline antimalarial compound, inhibits ASOR degradation at concentrations greater than 0.2 mM by neutralizing intracellular acid compartments. This leads to alterations in surface receptor number, receptor-ligand dissociation, and receptor recycling. We have investigated the effects of primaquine on 125I-ASOR uptake and degradation as a function of primaquine concentration and duration of exposure. Concentrations below those required for neutralization of acidic compartments block 125I-ASOR degradation in HepG2 cells and lead to intracellular ligand accumulation. This effect is maximal at 80 microM primaquine. The intracellular 125I-ASOR is undegraded, dissociated ...

1991-02-01

376

Low concentrations of primaquine inhibit degradation but not receptor-mediated endocytosis of asialoorosomucoid by HepG2 cells  

International Nuclear Information System (INIS)

Asialoorosomucoid (ASOR) is internalized and degraded by HepG2 cells after binding to the asialoglycoprotein (ASGP) receptor, internalization through the coated pit/coated vesicle pathway, and trafficking to lysosomes. Primaquine, an 8-aminoquinoline antimalarial compound, inhibits ASOR degradation at concentrations greater than 0.2 mM by neutralizing intracellular acid compartments. This leads to alterations in surface receptor number, receptor-ligand dissociation, and receptor recycling. We have investigated the effects of primaquine on 125I-ASOR uptake and degradation as a function of primaquine concentration and duration of exposure. Concentrations below those required for neutralization of acidic compartments block 125I-ASOR degradation in HepG2 cells and lead to intracellular ligand accumulation. This effect is maximal at 80 microM primaquine. The intracellular 125I-ASOR is undegraded, dissociated ...

377

Internalized insulin-receptor complexes are unidirectionally translocated to chloroquine-sensitive degradative sites. Dependence on metabolic energy  

Energy Technology Data Exchange (ETDEWEB)

Insulin receptors on the surface of isolated rat adipocytes were photoaffinity labeled at 12 degrees C with the iodinated photoreactive insulin analogue, 125I-B2 (2-nitro-4-azidophenylacetyl)-des-PheB1-insulin, and the pathways in the intracellular processing of the labeled receptors were studied at 37 degrees C. During 37 degrees C incubations, the labeled 440-kDa insulin receptors were continuously internalized (as assessed by trypsin inaccessibility) and degraded such that up to 50% of the initially labeled receptors were lost by 120 min. Metabolic poisons (0.125-0.75 mM 2,4-dinitrophenol (DNP) and 1-10 mM NaF), which led to dose-dependent depletion of adipocyte ATP pools, inhibited receptor loss, and caused up to 3-fold increase in intracellular receptor accumulation. This effect was due to inhibition of intracellular receptor degradation, and there was no apparent effect of the metabolic poisons on initial internalization of the receptors. ...

1988-04-25

378

Incorporation of "1"4C-linoleic acid in cerebrosides of psoriatic and normal human skin  

International Nuclear Information System (INIS)

It was shown that the incorporation of "1"4C-linoleic acid in cerebrosides of normal and psoriatic human skin is different. In psoriatic epidermis and corium the turnover of this fatty acid is significantly elevated. It is suggested that in psoriasis the epidermal cell is not able to build up a regular carbohydrate sequences of lipids because the false carbohydrate chain activates the degradation of glycolipids and in compensating for the increased degradation raises the synthesis rate of glycolipids. (orig./MG).

379

Enhanced Degradation of an Endocrine-Disrupting Chemical, Butyl Benzyl Phthalate, by Fusarium oxysporum f. sp. pisi Cutinase  

UK PubMed Central (United Kingdom)

Compared to yeast esterase, fungal cutinase degraded butyl benzyl phthalate (BBP) far more efficiently; i.e., almost 60% of the BBP disappeared within 7.5 h. Also, the final chemical composition significantly...Full Text Available

2002-09-01

380

DIMINISHED DEGRADATION OF MYELIN BASIC PROTEIN BY ANTI-SULFATIDE ANTIBODY AND INTERFERON-? IN MYELIN FROM GLIA MATURATION FACTOR-DEFICIENT MICE  

UK PubMed Central (United Kingdom)

In this study we show the effect of anti-sulfatide (RmAb) antibodies and inflammatory cytokines, TNF-α and IFN-γ in inducing myelin basic protein (MBP) degradation in myelin...Full Text Available

2007-06-01

381

Alkane degradation under anoxic conditions by a nitrate-reducing bacterium with possible involvement of the electron acceptor in substrate activation  

UK PubMed Central (United Kingdom)

Microorganisms can degrade saturated hydrocarbons (alkanes) not only under oxic but also under anoxic conditions. Three denitrifying isolates (strains HxN1, OcN1, HdN1) able to grow under anoxic conditions...Full Text Available

2011-02-01

382

Volatiles of Mount St. Helens and their origins  

Energy Technology Data Exchange (ETDEWEB)

Analyses have been made of gases in clouds apparently emanating from Mount Saint Helens. Despite appearances, most of the water in these clouds does not issue from the volcano. Even directly above a large fumarole deltaD and delta/sup 10/O data indicate that only half the water can come from the volcano. Isotopic and chemical evidence also shows the steam in the volcano (-33.0 per mol deltaD) from which a condensate of 0.2 N HCl was obtained is not a major cause of the explosions. The steam in the volcano is derived from a metamorphic brine in the underlying Tertiary meta andesite. The gas that caused the explosive eruptions is carbon dioxide.

1984-09-01

383

Tetrazine explosives  

Energy Technology Data Exchange (ETDEWEB)

The synthesis and properties of various 1,2,4,5-tetrazine explosives and energetic materials are described. These are the nitrate and perchlorate salts of 3,6-diguanidino-1,2,4,5-tetrazine, the nitrate and perchlorate salts of 3,6-diguanidino-1,2,4,5-tetrazine-1,4-di-N-oxide, 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine and its 1,4-di-N-oxide derivative, 3,3'-azobis(6-amino-1,2,4,5-tetrazine) and its oxidation products. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

2004-08-01

384

Safety designs for sludge ducts in brown coal briquetting plants  

Energy Technology Data Exchange (ETDEWEB)

Studies technological safety of installing a water spray pressure vessel between electrostatic dedusters and coal sludge ducts. These sprays are in use elsewhere for steam generator ash removal. Dust ignition and explosion tests were carried out to examine flame and pressure wave propagation through the vessel into ducts. Water jet diameter, amount of water sprayed and coal dust removed were varied. Pressure waves exceeded 250 Pa. Test results show the vessel to be suitable for installation in briquetting plants due to its flame and explosion barrier effect and extermination of smoldering dust fires. The only disadvantage of the vessel is seen as its water and electric power consumption; about 8/sup 3//h of water and 1.5 kW/h of power per vessel serving dedusters of a 2,200 m/sup 2/ rotary brown coal dryer.

1987-06-01

385

Safe design of mud ditches in briquetting factories  

Energy Technology Data Exchange (ETDEWEB)

The authors study technological safety of installing a water spray pressure vessel between electrostatic deduster and coal sludge ducts. These sprays are in use elsewhere for steam generator ash removal. Dust ignition and explosion tests were carried out to examine flame and pressure wave propagation through the vessel into ducts. Water jet diameter, amount of water sprayed and coal dust removed were varied. Pressure waves exceeded 250 Pa. Test results show the vessel to be suitable for installation in briquetting plants due to its flame and explosion barrier effect and extermination of smoldering dust fires. The only disadvantage of the vessel is seen as its water and electric power consumption: about 8 m/sup 3//h of water and 1.5 kW/h of power per vessel serving dedusters of a 2,200 m/sup 2/ rotary brown coal dryer. (MOS).

1987-06-01

386

Loading of wellbores with explosives  

Energy Technology Data Exchange (ETDEWEB)

Bags of explosive are loaded rapidly into deep wellbores by suspending a rigid positioning tube partway into the wellbore, and loading the bags into the tube, the bags being prevented from dropping through the open bottom end of the tube by a cord attached to the lowermost bag and secured at the upper end of the tube when the tube-suspending cable is in tension by a cordsecuring/releasing means, E.G., a pivotable bar having a hook on one end. When the bag-laden tube is lowered to the bottom of the wellbore, or to a column of bags previously placed therein, the tension on the cable is relaxed and the cord is released, allowing the positioning tube thereafter to be raised to the surface for re-use, leaving the cord and bags in the wellbore. Freedom of the bag-supporting cord to move with respect to the positioning tube when the latter is raised to the surface is assured by threading the cord through plastic tubing mounted to the wall of the positioning tube and ...

1983-04-26

387

Genomic architecture of aggression: Rare copy number variants in intermittent explosive disorder  

British Library Electronic Table of Contents (United Kingdom)

Abstract Copy number variants (CNVs) are known to be associated with complex neuropsychiatric disorders (e.g., schizophrenia and autism) but have not been explored in the isolated features of aggressive behaviors such as intermittent explosive disorder (IED). IED is characterized by recurrent episodes of aggression in which individuals act impulsively and grossly out of proportion from the involved stressors. Previous studies have identified genetic variants in the serotonergic pathway that play a role in susceptibility to this behavior, but additional contributors have not been identified. Therefore, to further delineate possible genetic influences, we investigated CNVs in individuals diagnosed with IED and/or personality disorder (PD). We carried out array comparative genomic hybridizati...

2011-01-01

388

Gas-dynamic signs of explosive eruptions of volcanoes. 2. Model of homogeneous-heterogeneous nucleation. Specific features of destruction of the cavitating magma  

British Library Electronic Table of Contents (United Kingdom)

The dynamics of state of the crystallite-containing magma is studied within the framework of the gas-dynamic model of bubble cavitation. The effect of crystallites on flow evolution is considered for two cases: where the crystallites are cavitation nuclei (homogeneous-heterogeneous nucleation model) and where large clusters of crystallites are formed in the magma in the period between eruptions. In the first case, decompression jumps are demonstrated to arise as early as in the wave precursor; the intensity of these jumps turns out to be sufficient to form a series of discrete zones of nucleation ahead of the front of the main decompression wave. Results of experimental modeling of an explosive eruption with ejection of crystallite clusters (magmatic ?bombs??) suggest that a cocurrent flow...

2009-01-01

389

Flame spread across surfaces of PBX 9501  

British Library Electronic Table of Contents (United Kingdom)

There is little flame spread data for homogeneous energetic materials and no data for nitramines. We report the results of flame spread experiments of PBX 9501 (HMX (cyclotetramethylenetetranitramine) based explosive). The horizontal flame spread rate, Sf, is of the same order of magnitude as normal deflagration and varies nearly as the square root of pressure, as our scaling analysis presented here predicts. In the vertical orientation, the flame propagation downward was observed to be slightly faster than horizontal flame spread, presumably because of the melt layer flowing downward on the sample. In an accident scenario, a charge may be fractured or the surface roughened. Consequently, we also examined the effect of roughness. Minor roughness created by explosives machining was found to...

2007-01-01

390

Explosives solve downhole problems  

Energy Technology Data Exchange (ETDEWEB)

Shaped charges were first used more than 30 years ago to perforate casing, cement sheath and reservoir to provide selective communication between the reservoir and well bore. Since then, advances have been made in design of shaped charge sand ancillary equipment. Penetration has increased considerably. Miniaturization of equipment allows passing through relatively small restrictions and effectively communicating with reservoirs. Gun debris has been drastically reduced and in some designs eliminated. Deep reservoirs can be effectively penetrated under down-hole environments exceeding 500 F and 20,000 psi. This work covers the problems encountered and reviews successful devices employing shaped charge and explosive technology.

1981-11-01

391

Electrical installations in locations with explosion hazards  

Energy Technology Data Exchange (ETDEWEB)

The optimization of the safety characteristics of electrical installations in industrial plants with explosion or fire hazards can be obtained only through a careful interdisciplinary study and analysis carried out at the onset of the plant project design phase. The least complex and costly and safest solutions are those which are born from plant designs which take into account the typology of the industrial process or technology, or which incorporate pollution abatement measures and adequate safety measures for the electrical installations. This paper provides examples to illustrate how the global plant economy is fundamentally dependant upon a multi-disciplinary initial effort in design analyses. Comments are made relevant to the adequacy of the safety requirements established by existing and planned Italian norms in dealing with safety and fire protection for high-tech industrial plant electrical installations.

1987-11-01

392

Detection of explosives in traces by laser induced breakdown spectroscopy: Differences from organic interferents and conditions for a correct classification  

British Library Electronic Table of Contents (United Kingdom)

With the aim to study and to improve LIBS capability for detecting residues of energetic compounds in air surrounding, nine types of explosives and some potential interferents, placed in small quantities on a metallic support, were interrogated by a laser. Shot-to-shot behavior of the line intensities relative to the sample constituents was studied. The detected plasma was not stoichiometric and the line intensities, as well as their ratios, were changing even for an order of magnitude from one sampling point to another, particularly in the case of aromatic compounds. We explained some sources of such LIBS signal's behavior and this allowed us to establish a data processing procedure, which leads to a good linearization among the data sets. In this way, it was possible to determine some re...

2011-01-01

393

Comparison of the Influence of Temperature on the High-Strain-Rate Mechanical Responses of PBX 9501 and EDC37  

British Library Electronic Table of Contents (United Kingdom)

Many high-strain-rate compression measurements (2000 per second) using a specially designed split Hopkinson pressure bar (SHPB) for the plastic-bonded explosive PBX9501 have been reported in the literature, but there is a sparsity of data for a United Kingdom polymer-bonded explosives (PBX) known as EDC37. Both EDC37 and PBX9501 are cyclotetramethylenetetranitramine-based (HMX-based) PBXs with high filler contents. The binder systems for the PBXs are very different: EDC37 consists of a nitroplasticized nitrocellulose and PBX9501 a nitroplasticized ESTANE. PBX9501 exhibits nearly invariant fracture strains of ?1.5?pct as a function of temperature at high strain rates, whereas EDC37 fails at ?2 to 2.5?pct. The maximum compressive strengths for both PBXs were measured at 150?Mpa at ?55??C, bu...

2008-01-01

394

Analysis of in-situ fracture of oil sand formations by explosives  

Energy Technology Data Exchange (ETDEWEB)

An analytical model is proposed for the design and simulation of in-situ fracture of deep oil sand formations. This model is based on the finite element variational principle in conjunction with special empirical modules to characterize in-situ oil sands behavior. A computer code by the name of SANFRAC was developed to handle the dynamic fracture of formations induced by explosives. Simulation of hydraulic fracture processes can be treated by the same code as special cases using the quasi-static analysis. Numerical case studies by the SANFRAC code indicate that extensive horizontal fracture can be achieved by dynamic loads with proper fracture starters configured at the injection well. The unique advantage of the dynamic fracturing technique over the hydraulic fracture methods is also demonstrated by these studies.

1987-03-01

395

A Complete Detonator, Booster, and Main Charge Study of LX-07/PBX 9502  

British Library Electronic Table of Contents (United Kingdom)

Abstract A complete study of an exploding bridgewire detonator (EBW), an LX-07 hemispherical booster and a PBX 9502 outer shell are described. Breakout times from all three are listed in terms of first impact on the booster, i.e., code times. Lucite windows are also used to obtain particle velocities at the edges of each explosive, and these are converted into explosive pressures. The key to modeling is the use of the profile of the aluminum detonator can as it impacts the booster, i.e., we need to know the curvature of the end of the booster can. Modeling even with coarse zoning shows that (i) using reactive flow in the booster is better than programmed burn, (ii) creating the flyer curvature helps, and (iii) creating the time differences of flyer impact helps even more.

2011-01-01

396

Life evaluation of insulating materials for electric cable by accelerated thermal-radiation combined aging  

Energy Technology Data Exchange (ETDEWEB)

Radiation-and-thermal-combined degradation of ethylene-propylene rubber (EP rubber) and chlorosulfonated polyethylene (CSM) as cable insulating and jacketing materials were evaluated by accelerated aging tests and a method to assess the lifetime of these materials under practical application was studied. EP rubber and CSM of experimental formulation were degraded at accelerated rates, that are 50 [approx] 1000 times the degradation rate under a standard condition (1Gy/h, 50degC). The degradation was investigated by measuring the tensile properties. In the accelerated aging tests, rates of elongation decrease owing to degradation for both EP rubber and CSM were in proportion to increase in accelerated rate. Behaviors of elongation changes showed little difference with accelerated rate. EP rubber lifetime estimated from sequential aging test had a tendency to extend beyond that from ...

1992-10-01

397

Life evaluation of insulating materials for electric cable by accelerated thermal-radiation combined aging  

International Nuclear Information System (INIS)

Radiation-and-thermal-combined degradation of ethylene-propylene rubber (EP rubber) and chlorosulfonated polyethylene (CSM) as cable insulating and jacketing materials were evaluated by accelerated aging tests and a method to assess the lifetime of these materials under practical application was studied. EP rubber and CSM of experimental formulation were degraded at accelerated rates, that are 50 #approx# 1000 times the degradation rate under a standard condition (1Gy/h, 50degC). The degradation was investigated by measuring the tensile properties. In the accelerated aging tests, rates of elongation decrease owing to degradation for both EP rubber and CSM were in proportion to increase in accelerated rate. Behaviors of elongation changes showed little difference with accelerated rate. EP rubber lifetime estimated from sequential aging test had a tendency to extend beyond that from ...

1992-01-01

398

Fundamental study on evaluation method for alkali-resistance of fibers. Kakushu sen'i no tai arukarisei no hyokaho ni kansuru kiso kenkyu  

Energy Technology Data Exchange (ETDEWEB)

In order to clarify the alkali-resistance of fibers to be utilized as reinforcing materials for concrete, such as glass fiber, Aramid fiber, and carbon fiber, accelerated aging tests in alkaline solution were conducted. In detail, the degree of degradation of the fracture strength and Young's modulus were investigated through static tensile strength tests after soaking in alkaline solution of these fibers and then the mechanism of degradation was examined by observation using a scanning electron microscope. The conclusion obtained was as follows. Glass fiber was easily degraded in the alkaline solution and the progress of degradation was simulated quantitatively by the method proposed in this paper, which was based on a diffusion theory. Both Aramid fiber and carbon fiber showed a significant alkali-resistance without degrading. The reaction of glass fiber with alkaline ...

1994-05-20

399

Effects of DC gate and drain bias stresses on the degradation of excimer laser crystallized polysilicon thin film transistors  

Energy Technology Data Exchange (ETDEWEB)

The effects of gate and drain bias stresses on thin film transistors fabricated in polysilicon films crystallized using the advanced sequential lateral solidification excimer laser annealing (SLS ELA) process, which yields very elongated polysilicon grains and allows the fabrication of TFTs without grain boundary barriers to current flow, are investigated as a function of the active layer thickness and of the TFT orientation relative to the grains. The application of hot carrier stress, with a condition of V{sub GS} = V{sub DS}/2, was determined to induce threshold voltage, subthreshold swing and transconductance degradation for TFTs in thicker polysilicon films and the associated stress-induced increase in the active layer trap density was evaluated. However, this device degradation was drastically reduced for TFTs fabricated in ultra-thin films. Furthermore, the application of the same stress condition to TFTs oriented vertically to the ...

2005-01-01

400

Effects of DC gate and drain bias stresses on the degradation of excimer laser crystallized polysilicon thin film transistors  

International Nuclear Information System (INIS)

The effects of gate and drain bias stresses on thin film transistors fabricated in polysilicon films crystallized using the advanced sequential lateral solidification excimer laser annealing (SLS ELA) process, which yields very elongated polysilicon grains and allows the fabrication of TFTs without grain boundary barriers to current flow, are investigated as a function of the active layer thickness and of the TFT orientation relative to the grains. The application of hot carrier stress, with a condition of V_G_S = V_D_S/2, was determined to induce threshold voltage, subthreshold swing and transconductance degradation for TFTs in thicker polysilicon films and the associated stress-induced increase in the active layer trap density was evaluated. However, this device degradation was drastically reduced for TFTs fabricated in ultra-thin films. Furthermore, the application of the same stress condition to TFTs oriented vertically to the elongated ...

2005-01-01

401

Development of Nuclear Materials and Degradation Database  

International Nuclear Information System (INIS)

There are about 440 operating nuclear power reactors in the world including 20 units from Korea. The average age of the reactors is more than 20 years and many of them are approaching to their original 30 or 40 years licensing terms. Even though some failures were reported in components or pipes of nuclear power plants (NPPs), these NPPs are considered to be too valuable to stop their operation at the end of design life. Therefore, the long-term operation of NPPs has become a worldwide trend based on technical and economic consideration. In order to ensure safe long-term operation of NPPs, it is increasingly necessary to adopt new approaches to deal with nuclear materials aging and degradation. Proactive Material Degradation Assessment (PMDA) is one of the key elements of these new approaches. Many kinds of background information such as materials and degradation history of components or piping in NPP plant are also needed ...

2010-10-01

402

Coupling of Realistic Rate Estimates with Genomics for Assessing Contaminant Attenuation and Long-Term Plume Containment - Task 4: Modeling - Final Report  

Energy Technology Data Exchange (ETDEWEB)

Trichloroethene (TCE), a common groundwater contaminant, can be degraded under certain conditions by microorganisms that occur naturally in the subsurface. TCE can be degraded under anaerobic conditions to less chlorinated compounds and ultimately into the non-chlorinated, non-hazardous end product, ethene, via anaerobic reductive dechlorination (ARD). ARD is widely recognized as a TCE degradation mechanism, and occurs in active groundwater remediation and can occur during monitored natural attenuation (MNA). MNA relies on natural processes, such as dispersion and degradation, to reduce contaminant concentrations to acceptable levels without active human intervention other than monitoring. TCE can also be biodegraded under aerobic conditions via cometabolism, in which microbial enzymes produced for other purposes fortuitously also react with TCE. In cometabolism, TCE is oxidized directly to ...

2005-10-31

403

Vertical and Horizontal Variations in the Physiological Diversity of the Aerobic Chemoheterotrophic Bacterial Microflora in Deep Southeast Coastal Plain Subsurface Sediments  

UK PubMed Central (United Kingdom)

Aerobic chemoheterotrophic bacteria were isolated from surface soils and coastal plain subsurface (including deep aquifer) sediments (depths to 265 m) at a study site near Aiken, S.C., by plating on...Full Text Available

1989-05-01

404

Telavancin versus Standard Therapy for Treatment of Complicated Skin and Skin Structure Infections Caused by Gram-Positive Bacteria: FAST 2 Study  

UK PubMed Central (United Kingdom)

Telavancin is a bactericidal lipoglycopeptide with a multifunctional mechanism of action. We conducted a randomized, double blind, active-control phase II trial. Patients ≥18 years of age with...Full Text Available

2006-03-01

405

Staphylococcus aureus Enterotoxin D Is Secreted in Milk and Stimulates Specific Antibody Responses in Cows in the Course of Experimental Intramammary Infection  

UK PubMed Central (United Kingdom)

An enterotoxin D (SED)-producing strain of Staphylococcus aureus was used to infect one mammary gland of each of 17 lactating dairy cows. All glands became infected and shed bacteria...Full Text Available

2006-06-01

406

Radiation higienization possibility and perspectives  

International Nuclear Information System (INIS)

Food irradiation is the process of exposing food to an ionizing energy to kill harmful bacteria and other organisms and extend shelf-life. It is a safe process and has been approved by some 50 countries worldwide and applied commercially in the USA, Japan, China and several European countries for many years. Trends law regulations and new applications in Europe and another countries has been described. (author)

2005-09-07

407

Quality engineering and control. Annual progress report, January-December 1981  

International Nuclear Information System (INIS)

Brief summaries are given of research carried out in the following areas: absorption spectroscopy of titanium, niobium, and molybdenum in uranium alloys; atomic absorption spectroscopy of selenium in stainless steel, computer program improvements for spectrophotometer control, and detection of beryllium in stack gases; electrolysis for inactivation of bacteria in cooling-tower water; improved solvent analysis by gas chromatography; sequential radionuclide separation for various sample matrices; progress on an electron microprobe analyzer; and miscellaneous projects.

408

One-carbon metabolism in methanogenic bacteria: analysis of short-term fixation products of 14CO2 and 14CH3OH incorporated into whole cells.  

UK PubMed Central (United Kingdom)

Methanobacterium thermoautotrophicum, M. ruminantium, and Methanosarcina barkeri were labeled with 14CO2 (14CO2 + H14CO3- + 14CO32-) for from 2 to 45 s. Radioactivity was recovered in coenzyme M derivatives,...Full Text Available

1978-10-01

409

Moessbauer studies of the molybdenum-iron-protein in the nitrogenase of Xanthobacter autotrophicus GZ 29. Moessbaueruntersuchungen am Molybdaen-Eisen-Protein der Nitrogenase von Xanthobacter Autotrophicus GZ 29  

Energy Technology Data Exchange (ETDEWEB)

Biological cells of the nitrogen fixating bacteria Xanthobacter autotrophicus GZ 29 have been cultivated with 57-Fe, and from the nitrogenase of these cells the 57-Fe marked molybdenum-iron-protein is extracted. The Moessbauer spectra of this enzyme show that the structure of the iron cluster is similar to the structure in the molybdenum-iron-proteins of Azotobacter vinelandii, Klebsiella pneumoniae or Clostridium pasteurianum.

1983-05-01

410

Mercury Removal, Methylmercury Formation, and Sulfate-Reducing Bacteria Profiles in Wetland Mesocosms Containing Gypsum-Amended Sediments and Scirpus californicus  

Energy Technology Data Exchange (ETDEWEB)

A pilot-scale model was constructed to determine if a wetland treatment system (WTS) could effectively remove low-level mercury from an outfall located at the Department of Energy's Savannah River Site.

2001-03-02

411

Ecology and resistance of Moraxella-Acinetobacter  

International Nuclear Information System (INIS)

The diverse microenvironments of foods, changing with processing and preservation, might provide conditions that would enhance the growth of microorganisms which are the principal cause of spoilage, off-odor and unpleasant flavor in foods. Radiation is a potential process which may provide a product with far superior microbial quality for food preservation, by reduction of microbial population; elimination of food-borne pathogens; extension of shelf-life; and reduction of spoilage. The aim of irradiation at low dose level is to eliminate certain microorganisms, especially spoilage types and those of public health significance. But, the radurization dose allows the outgrowth of radioresistant bacteria. Certain strains of Moraxella-Acinetobacter (M-A) groups have been recognized as radioresistant bacteria (Welch and Maxcy, 1975), which may have gone unnoticed by food microbiologists, since these bacteria have not been ...

1977-01-01

412

Crystallization and preliminary X-ray analysis of three dUTPases from Gram-positive bacteria  

UK PubMed Central (United Kingdom)

All organisms examined to date possess a dUTPase that performs the important function of efficiently hydrolyzing dUTP to dUMP in order to prevent the incorporation of dUTP into DNA. Three putative dUTPases...Full Text Available

413

Comparative In Vitro Activity Profiles of Novel Bis-Indole Antibacterials against Gram-Positive and Gram-Negative Clinical Isolates?  

UK PubMed Central (United Kingdom)

Antimicrobial susceptibilities of 233 Gram-positive and 180 Gram-negative strains to two novel bis-indoles were evaluated. Both compounds were potent inhibitors of Gram-positive bacteria, with MIC90...Full Text Available

2010-09-01

414

Campylobacter jejuni Fatty Acid Synthase II: Structural and functional analysis of ?-hydroxyacyl-ACP dehydratase (FabZ)  

UK PubMed Central (United Kingdom)

Fatty acid biosynthesis is crucial for all living cells. In contrast to higher organisms, bacteria use a type II fatty acid synthase (FAS II) composed of a series of individual proteins, making...Full Text Available

2009-03-06

415

Biosorption for the separation of radionuclides from drainage and process waters of the uranium mining industry  

Energy Technology Data Exchange (ETDEWEB)

Biosorption means the storage of substances at the cell envelope. Different microbial biomasses were tested for the separation of radionuclides from mining waters. Results of a pilot plant demonstrate the ability of these techniques for water cleaning processes. An effluent concentration of lower than 1 mg/l (in most cases 0.1 mg/1) could be realized in a pilot plant by using pure cells of a methylotrophic strain of bacteria as well as using of a fungal mycelia.

1995-12-31

416

Ozone hazards incurred in #gamma#-plant operation  

International Nuclear Information System (INIS)

The irradiation of air produces some toxic gases such as ozone, nitric oxide, nitrogen dioxide, nitrogen trioxide, nitrogen tetroxide, nitric anhydride and nitrous oxide. Of these gases, ozone is the most important because of its toxicity and may be produced in such quantities as to constitute a health hazard within the irradiation room. The toxicity, and explosive characteristics of ozone and quantitative aspects of ozone production are discussed and ventilation requirements considered. (U.K.).

417

Mechanisms of EBW HE initiation  

Science.gov (United States)

Exploding bridgewire (EBW) initiation of high explosives (HE) has been used for many years without a clear understanding of the mechanisms involved. Evidence indicates that the shock pressures produced by the EBW may be insufficient for direct initiation and that the electric field about the wire at the time of burst ionizes the surface of the HE. We hypothesize that the ionization pre-sensitizes the HE so that a weak shock can then initiate a detonation wave. 13 refs., 7 figs.

1991-05-15

418

Galactic deuterium abundance as a test of cosmological models  

Energy Technology Data Exchange (ETDEWEB)

The problem on change of deuterium abundance in the process of galactic evolution (star evolution, supernova explosions, nucleosynthesis in supermassive objects) is considered. It is shown that the observable deuterium quantity in the interstellar medium must correspond to its cosmological abundance. This conclusion is independent of the rate of accretion of intergalactic gas by Galaxy. The effect of hypothetical pregalactic active objects on cosmological deuterium is small. It is poind out that observations of interstellar deuterium in absorbtion at lambda=91.6 cm are significant.

1982-02-01

419

Eliminating explosives  

Energy Technology Data Exchange (ETDEWEB)

The paper describes a way to control methane that is almost self-sufficient. The Methane Buster extracts methane from longwall mines. The machinery can run virtually unattended and is fuelled by a small proportion of the methane that it extracts. The most popular model is the size of a car and weighs 3000 lbs. With pump inlet sizes varying from 6 to 24 ins. The pumps can handle up to 30,000 CFM. 3 photos.

2005-12-01

420

Effect of the PVC system?s topology on the dielectric losses in the region of strong electric fields  

British Library Electronic Table of Contents (United Kingdom)

The electrophysical characteristics of the electric cable?s transition into a state of a heterogenic polymer system due to a wire?s explosion were examined. Using cyclic heating-cooling of the composite, the changes in its topology were observed. The latter makes it possible to regulate the dielectric characteristics of the system.

2011-01-01

421

Detection device for high explosives  

Energy Technology Data Exchange (ETDEWEB)

A portable fiber optic detector that senses the presence of specific target chemicals by electrostatically attracting the target chemical to an aromatic compound coating on an optical fiber. Attaching the target chemical to the coated fiber reduces the fluorescence so that a photon sensing detector records the reduced light level and activates an appropriate alarm or indicator.

1992-01-01

422

Characterization of detonator performance using photonic Doppler velocimetry  

Science.gov (United States)

Detonators are used to convert electrical or other energy into an explosive output. This output can then be used to initiate further explosive charges. To aid in the development of explosive systems, it is important to characterize the output of detonators, in particularly the pressure produced. Recent advances over the last five years in high-speed digitizing oscilloscopes and high-bandwidth photodiodes, driven primarily by the telecommunications industry, have enabled the development of a new type of interferometer for measuring high velocities, such as those found in detonics experiments. The Photonic Doppler Velocimeter (PDV) can be visualized as a fiber-based Michelson interferometer. The light from a single-mode fiber laser at 1550 nm is passed through a circulator, which acts to separate bi-directional light. The beam is then reflected via free-space optics off the surface of interest, and then focused back into the ...

2008-08-01

423

APSTNG: Neutron interrogation for detection of nuclear and CW weapons, explosives, and drugs  

Energy Technology Data Exchange (ETDEWEB)

A recently developed neutron diagnostic probe system has the potential to satisfy a significant number of van-mobile and fixed- portal requirements for nondestructive verification of sealed munitions and detection of contraband explosives and drugs. The probe is based on a unique associated-particle sealed-tube neutron generator (APSTNG) that interrogates the object of interest with a low-intensity beam of 14-MeV neutrons generated from the deuterium-tritium reaction and that detects the alpha-particle associated with each neutron. Gamma-ray spectra of resulting neutron inelastic scattering and fission reactions identify nuclides associated with all major chemicals in chemical warfare agents, explosives, and drugs, as well as many pollutants and fissile and fertile special nuclear material. Flight times determined from determined from detection times of the gamma-rays and alpha-particles yield a separate tomographic image of each identified ...

1992-07-01

424

Waste Handling Shaft concrete liner degradation conclusions and recommendations  

International Nuclear Information System (INIS)

The primary function of the Waste Handling Shaft (WHS) at the Waste Isolation Pilot Plant (WIPP) is to permit the transfer of radioactive waste from the surface waste handling building to the underground storage area. It also serves as an intake shaft for small volumes of air during normal storage operations and as an emergency escape route. Part of the construction was the placement of a concrete liner and steel reinforced key in 1984. During a routine shaft inspection in May 1990, some degradation of the WHS concrete liner was observed between the depths of 800 and 900 feet below the ground surface. Detailed investigations of the liner had been carried out by Sandia National Laboratories and by Westinghouse Electric Corporation Waste Isolation Division (WID) through Lankard Materials Laboratory. Observations, reports, and data support the conclusion that the concrete degradation, resulting from attack by chemically aggressive brine, is a ...

425

Phytoremediation potential of Portulaca grandiflora Hook. (Moss-Rose) in degrading a sulfonated diazo reactive dye Navy Blue HE2R (Reactive Blue 172)  

British Library Electronic Table of Contents (United Kingdom)

Wild and tissue cultured plants of Portulaca grandiflora Hook. have shown to be able to decolorize a sulfonated diazo dye Navy Blue HE2R (NBHE2R) up to 98% in 40h. A significant induction in the activities of lignin peroxidase, tyrosinase and DCIP reductase was observed in the roots during dye decolorization. The wild plants and tissue cultures could independently decolorize and degrade NBHE2R into metabolites viz. N-benzylacetamide and 6-diazenyl-4-hydroxynaphthalene-2-sulfonic acid. A dye mixture and a textile effluent were also decolorized efficiently by P. grandiflora. The phytotoxicity study revealed reduction in the toxicity due to metabolites formed after dye degradation.

2011-01-01

426

Photocatalytic degradation of gaseous pyridine over zeolite-supported titanium dioxide  

Energy Technology Data Exchange (ETDEWEB)

The photocatalyzed degradation of pyridine in the gas phase was investigated using titanium dioxide semiconductor supported on mordenite. The complete mineralization was found to occur over a catalyst containing 75 wt% TiO{sub 2} and 25 wt% mordenite in about 180 min in the presence of saturated water vapor at O{degrees}C (4.6 Torr). Low water vapor pressure of 0.096 Torr was found to be sufficient to achieve a reasonably high percentage and rate of degradation. Diffusion of pyridine within the catalyst adversely affects the activity when the thickness of the catalyst coating exceeds the penetration depth of illumination. The activity of the zeolite-supported catalysts was higher than that of TiO{sub 2}. The photonic efficiency for the complete mineralization of pyridine to CO{sub 2} was determined to be 0.48. 29 refs., 6 refs., 1 tab.

1994-09-01

427

Oxidation of polycaprolactone to induce compatibility with other degradable polyesters  

British Library Electronic Table of Contents (United Kingdom)

Chemical modification of poly(?-caprolactone) PCL by oxidation with potassium permanganate in solution was investigated. According to the data obtained from Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance 1H NMR, after the oxidation reactions the PCL chains exhibited new functional groups (vinyl and hydroxyl) and possible intermolecular recombination, producing an oxidized-polycaprolactone (PCL-OX). Solution viscometry indicated that degradation also occurred during the oxidation reactions (30% drop in viscosity average molecular weight was detected). Differential scanning calorimetry (DSC) also indicated that PCL was chemically modified and degraded. The successive self-nucleation/annealing (SSA) treatment confirmed that a reduction (or interruption) in line...

2007-01-01

428

Measurements of bragg curve for 75 MeV/u "1"2C ion beam and its inactivation effect on melanoma cells  

International Nuclear Information System (INIS)

Relative doses of 75 MeV/u "1"2C ion beam after passing through different thickness of degraders were measured with the double ionization chamber method. The degrader's thickness equalized to penetration depth of the beam in water and its Bragg curve were obtained. The measured Bragg curve is compared with that calculated based on a model set up by the authors. Meanwhile, the inactivation effect of the ion beam passing through different thickness of degraders on melanoma (B_1_6) cells was measured, and the corresponding survival fraction data for B_1_6 cells were acquired

1998-08-01

429

Degradation of gas turbine coatings and life assessment  

Energy Technology Data Exchange (ETDEWEB)

MCrAlY coatings are widely used on hot section components of gas turbines to provide hot corrosion and/or oxidation protection by formation of an oxide layer on the surface. As the protective oxide scale exfoliates during service, aluminum from the coating diffuses outward for reformation of the protective scale. Aluminum may also diffuse inward due to the differences in composition between the coating and the substrate. Thus, the coatings degrade due to oxidation, oxide scale spallation, and inward and outward diffusion of aluminum. Service life of these coatings is controlled by the aluminum content in the coating, operating temperature and start- shutdown cycles. In-service degradation of CoCrAlY and CoNiCrAlY coatings is presented. A procedure to predict the remaining service life of coatings under oxidizing conditions is discussed. (orig.) 12 refs.

1998-12-31

430

Degradation of antibiotics in water by non-thermal plasma treatment.  

Science.gov (United States)

The decomposition of three ?-lactam antibiotics (amoxicillin, oxacillin and ampicillin) in aqueous solution was investigated using a dielectric barrier discharge (DBD) in coaxial configuration. Solutions of concentration 100 mg/L were made to flow as a film over the surface of the inner electrode of the plasma reactor, so the discharge was generated at the gas-liquid interface. The electrical discharge was operated in pulsed regime, at room temperature and atmospheric pressure, in oxygen. Amoxicillin was degraded after 10 min plasma treatment, while the other two antibiotics required about 30 min for decomposition. The evolution of the degradation process was continuously followed using liquid chromatography-mass spectrometry (LC-MS), total organic carbon (TOC) and chemical oxygen demand (COD) analyses. PMID:21514950

2011-04-06

431

Collapse pressures of bilayered biodegradable stents  

British Library Electronic Table of Contents (United Kingdom)

Biodegradable helicoidal stent prototypes made up of layers of poly-L-lactic acid (PLLA) and poly(L-lactic-co-glycolic acid) (PLGA) polymers were fabricated by temperature conditioning the stents at different stages of fabrication. The process incorporated elastic memory, or self-expandability in the stent, which is desirable to minimize stent recoil. The collapse pressures of such stents were studied, with and without in vitro degradation. The effects of thickness and the composition of each layer on the collapse pressure were modeled using the simple series model. Results of the in vitro studies for over 3 months showed that collapse pressure of the stents depended mainly on the degradation and other side-effects brought about by the degradation of different polymer compositions. General...

2006-01-01

432

Catalyzed oxidative degradation of methylene blue by in situ generated cobalt (II)-bicarbonate complexes with hydrogen peroxide  

British Library Electronic Table of Contents (United Kingdom)

Oxidative degradation of methylene blue (MB) by Co^2^+-HCO3^- system with H2O2 in aqueous solution was studied. Nearly complete decolorization of the dye was obtained in less than 50min in diluted NaHCO3 solution (25mM) in the presence of only 20mM Co^2^+ ions. Meanwhile, the conjugated structure and phenyl rings of the MB molecule were destroyed or even broken down into small organic acids and inorganic ions, as indicated by FT-IR spectra and ion-chromatography. Photoluminescence probing and radical scavenging technologies suggested that the reaction of MB degradation in this system mainly involved the generation and participation of hydroxyl radicals. Furthermore, by cyclovoltammetric measurements, the in situ formed different complexes between Co^2^+ and HCO3^- were observed at differen...

2011-01-01

433

Analysis on anomalous degradation in silicon solar cell designed for space use  

Energy Technology Data Exchange (ETDEWEB)

Recently, we have found the anomalous degradation of electrical performance in silicon solar cells irradiated with charged particles in a high-fluence region. This anomalous phenomenon has two typical features, which are sudden-drop-down of electrical performances in a high-fluence region and slight recovery of the short circuit current I{sub SC} just before the sudden-drop-down. These features cannot be understood by a conventional model coming from the decrease of minority-carriers life-time. We introduce this anomalous degradation of the electrical performance in Si solar cells irradiated with electrons or protons. We also report the result of simulation for the fluence dependence of the I{sub SC}, and discuss the mechanism of this anomalous phenomenon. (author)

1997-03-01

434

Wire chamber degradation at the Argonne ZGS  

International Nuclear Information System (INIS)

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

1986-01-16

435

Wire chamber degradation at the Argonne ZGS  

Energy Technology Data Exchange (ETDEWEB)

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

1986-01-01

436

Ubiquitin-Dependent Degradation of p53 Protein despite Phosphorylation at its N-Terminus by Acetaminophen  

UK PubMed Central (United Kingdom)

We previously reported that acetaminophen (APAP) caused apoptosis of C6 glioma cells. Therefore, we hypothesized that the level of p53, which usually stimulates apoptosis, might be increased...Full Text Available

2006-04-01

437

The Subtilisin-Like Protease AprV2 Is Required for Virulence and Uses a Novel Disulphide-Tethered Exosite to Bind Substrates  

UK PubMed Central (United Kingdom)

Many bacterial pathogens produce extracellular proteases that degrade the extracellular matrix of the host and therefore are involved in disease pathogenesis. Dichelobacter nodosus...Full Text Available

2010-11-01

438

The IBR5 phosphatase promotes Arabidopsis auxin responses through a novel mechanism distinct from TIR1-mediated repressor degradation  

UK PubMed Central (United Kingdom)

BackgroundIn Arabidopsis, INDOLE-3-BUTYRIC ACID RESPONSE5 (IBR5), a putative dual-specificity protein phosphatase,...Full Text Available

439

THE ANAEROBIC TREATMENT OF WASTES CONTAINING RECALCITRANT AND INHIBITORY COMPOUNDS  

Environmental Research Database

ObjectivesObjectives Not AvailableDescriptionA collaborative study of the anaerobic treatment of wastes containing recalcitrant and inhibitory compounds using the SERC Anaerobic facility, in particular biomass structure, monitoring and control, catabolism and toxicity, pre-acidification and microbial growth and mesophilic and thermophilic lignocellulose degradation.~%~

1995-01-20

440

Synthesis and degradation of dinoflagellate plastid-encoded psbA proteins are light-regulated, not circadian-regulated  

UK PubMed Central (United Kingdom)

In many dinoflagellate species, the plastid genome has been proposed to exist as a limited number of single-gene minicircles, and many genes normally found in the plastid genome are nuclear-encoded....Full Text Available

2005-02-22

441

Synergistic Operation of the CAR2 (Ornithine Transaminase) Promoter Elements in Saccharomyces cerevisiae  

UK PubMed Central (United Kingdom)

Dal82p binds to the UISALL sites of allophanate-induced genes of the allantoin-degradative pathway and functions synergistically with the GATA family Gln3p and Gat1p transcriptional...Full Text Available

1999-11-01

442

Stability of prothrombin and factor VII in freeze-dried plasma  

UK PubMed Central (United Kingdom)

The stability of prothrombin and factor VII was studied using accelerated degradation tests in three preparations of freeze-dried pooled normal plasmas. In a previous report (Brozović, Gurd,...Full Text Available

1971-11-01

443

Soluble Epoxide Hydrolase Inhibition: Targeting Multiple Mechanisms of Ischemic Brain Injury with a Single Agent  

UK PubMed Central (United Kingdom)

SummarySoluble epoxide hydrolase (sEH) is a key enzyme in the metabolic conversion and degradation of P450 eicosanoids called epoxyeicosatrienoic acids (EETs). Genetic variations...Full Text Available

2009-03-01

444

Slow-Release Inoculation Allows Sustained Biodegradation of ?-Hexachlorocyclohexane  

UK PubMed Central (United Kingdom)

This study investigated the feasibility of a slow-release inoculation approach as a bioaugmentation strategy for the degradation of lindane (γ-hexachlorocyclohexane [γ-HCH]). Slow-release...Full Text Available

2006-01-01

445

Short-Term Metal/Organic Interface Stability Investigations of Organic Photovoltaic Devices: Preprint  

Energy Technology Data Exchange (ETDEWEB)

This paper addresses one source of degradation in OPV devices: the metal/organic interface. The basic approach was to study the completed device stability vs. the stability of the organic film itself as shown in subsequent devices fabricated from the films.

2008-05-01

446

Selective Degradation of Newly Synthesized Nonmessenger Simian Virus 40 Transcripts  

UK PubMed Central (United Kingdom)

By pretreating simian virus 40-infected BSC-1 cells with glucosamine, [3H]uridine labeling of both cellular and viral RNA can be halted instantaneously by addition of cold uridine. We have...Full Text Available

1978-11-01

447

SAMHD1: a new insight into HIV-1 restriction in myeloid cells  

UK PubMed Central (United Kingdom)

Human myeloid-lineage cells are refractory to HIV-1 infection. The Vpx proteins from HIV-2 and sooty mangabey SIV render these cells permissive to HIV-1 infection through proteasomal degradation of...Full Text Available

448

Raiders of the Lost Bark: Orangutan Foraging Strategies in a Degraded Landscape  

UK PubMed Central (United Kingdom)

Deforestation is rapidly transforming primary forests across the tropics into human-dominated landscapes. Consequently, conservationists need to understand how different taxa respond and adapt to these...Full Text Available

449

Purification and Characterization of a Membrane-Bound Protease from Chlamydomonas reinhardtii 1  

UK PubMed Central (United Kingdom)

In Chlamydomonas reinhardtii y-1, newly synthesized chlorophyll a/b-binding apoproteins are degraded when chlorophylls are not present for assembly of stable light-harvesting...Full Text Available

1992-07-01

450

Proteasomal chymotrypsin-like peptidase activity is required for essential functions of human monocyte-derived dendritic cells  

UK PubMed Central (United Kingdom)

The ubiquitin–proteasome pathway is the principal system for extralysosomal protein degradation in eukaryotic cells, and is essential for the regulation and maintenance of basic cellular processes,...Full Text Available

2007-01-01

451

Program listing for heat-pump seasonal-performance model (SPM). [CNHSPM  

Science.gov (United States)

The computer program CNHSPM is listed which predicts heat pump seasonal energy consumption (including defrost, cyclic degradation, and supplementary heat) using steady state rating point performance and binned weather data. (LEW)

1982-06-30

452

Permeability of frog mesenteric capillaries after partial pronase digestion of the endothelial glycocalyx.  

UK PubMed Central (United Kingdom)

1. The proteolytic enzyme pronase, which degrades the endothelial cell glycocalyx, was perfused through single capillaries of frog mesentery. Hydraulic conductivity (Lp) of each vessel was determined...Full Text Available

1990-09-01

453

Nucleoside Drugs Induce Cellular Differentiation by Caspase-Dependent Degradation of Stem Cell Factors  

UK PubMed Central (United Kingdom)

BackgroundStem cell characteristics are an important feature of human cancer cells and play a major role in the therapy resistance of tumours. Strategies to target cancer stem cells...Full Text Available

454

Nitrogen limitation and nitrogen fixation during alkane biodegradation in a sandy soil.  

UK PubMed Central (United Kingdom)

We investigated nutrient limitations during hydrocarbon degradation in a sandy soil and found that fixed nitrogen was initially a limiting nutrient but that N limitation could sometimes be overcome...Full Text Available

1993-09-01

455

Motion management with phase-adapted 4D-optimization  

UK PubMed Central (United Kingdom)

Cancer treatment with ionizing radiation is often compromised by organ motion, in particular for lung cases. Motion uncertainties can significantly degrade an otherwise optimized treatment plan....Full Text Available

2010-09-07

456

Molecular mechanisms of genetic adaptation to xenobiotic compounds.  

UK PubMed Central (United Kingdom)

Microorganisms in the environment can often adapt to use xenobiotic chemicals as novel growth and energy substrates. Specialized enzyme systems and metabolic pathways for the degradation of man-made...Full Text Available

1992-12-01

457

Microbial Anaerobic Demethylation and Dechlorination of Chlorinated Hydroquinone Metabolites Synthesized by Basidiomycete Fungi  

UK PubMed Central (United Kingdom)

The synthesis and degradation of anthropogenic and natural organohalides are the basis of a global halogen cycle. Chlorinated hydroquinone metabolites (CHMs) synthesized by basidiomycete fungi and present...Full Text Available

2004-01-01

458

Isolation and Identification of Achromobacter sp. DN-06 and Evaluation of Its Pyridine Degradation Kinetics  

British Library Electronic Table of Contents (United Kingdom)

We report the isolation of a new bacterium species (named as DN-06) that degrades pyridine, a model compound containing both carbon and nitrogen, from the aerobic activated sludge in a coking wastewater treatment plant. DN-06 was identified as Achromobacter sp. using 16S rDNA sequence analysis. In batch culture, more than 95% of pyridine (500?mg/L) was degraded within 18?h by DN-06 grown at 35?C and pH?8 with agitation at 170?rpm. Degradation experiments of pyridine at different initial concentrations (50?4,300?mg/L) revealed that pyridine was an inhibitory substrate, and that neither yield coefficient Y nor endogenous decay coefficient K d was a constant. The values of Y and K d were 0.55?0.74 and 0.0032?0.0057?h?1, respectively. Five kinetic models (Haldane, Yano, Aiba, Webb, and Monod) ...

2011-01-01

459

Increased degradation of MYPT1 contributes to the development of tolerance to nitric oxide in porcine pulmonary artery  

UK PubMed Central (United Kingdom)

Myosin phosphatase target subunit 1 (MYPT1) is the regulatory subunit of myosin light chain phosphatase (MLCP). It plays a critical role in vasodilatation induced by cGMP-elevating agents such as nitric...Full Text Available

2010-07-01

460

Increased Expression and Activity of Matrix Metalloproteinases Characterize Embolic Cardiac Myxomas  

UK PubMed Central (United Kingdom)

Tumor embolism occurs in 30 to 50% of all cases of cardiac myxoma, but the causes are still uncertain. Matrix metalloproteinases (MMPs) are proteolytic enzymes that degrade the extracellular matrix...Full Text Available

2005-06-01

461

In service inspection for steam generator tubes  

International Nuclear Information System (INIS)

In this paper the authors show the means putting in place for examination of steam generators tubes. These means (eddy current probes, ultrasonic testing) associated with a knowledge on degradation phenomena allow mapping controlled tubes and limiting undesirable obturations.

1987-11-24

462

Hierarchical and serial processing in the spatial auditory cortical pathway is degraded by natural aging  

UK PubMed Central (United Kingdom)

The compromised abilities to localize sounds and to understand speech are two hallmark deficits in aged individuals. The auditory cortex is necessary for these processes, yet we know little...Full Text Available

2010-11-03

463

Hexadecane mineralization in oxygen-controlled sediment-seawater cultivations with autochthonous microorganisms.  

UK PubMed Central (United Kingdom)

Laboratory studies investigated the influence of dissolved oxygen tension (DOT) on microbial degradation of hexadecane in cultures with sediment-seawater suspensions. With a fermentor system, it was...Full Text Available

1992-09-01

464

Hepatocyte entry leads to degradation of autoreactive CD8 T cells  

UK PubMed Central (United Kingdom)

Although most self-reactive T cells are eliminated in the thymus, mechanisms to inactivate or control T cells specific for extrathymic antigens are required and exist in the periphery. By investigating...Full Text Available

2011-10-04

465

Evaluation of the potential of pentachlorophenol degradation in soil by pulsed corona discharge plasma from soil characteristics.  

Science.gov (United States)

Chlorinated organics are frequently found as harmful soil contaminants and persisted for extended periods of time. A novel approach, named pulsed corona discharge plasma (PCDP), was employed for the degradation of pentachlorophenol (PCP) in soil. Experimental results showed that 87% of PCP could be smoothly removed in 60 min. Increasing pulse voltage, enhancing soil pH, lowering humic acid (HA) in soil and reducing granular size of the soil were found to be favorable for PCP degradation efficiency. Oxidation and physical processes simultaneously contributed to PCP removal in soil and ozone was the main factor in PCDP treatment. C-Cl bonds in PCP were cleaved during PCDP treatment by Fourier transform infrared spectroscopy (FTIR) analysis. The mineralization of PCP was confirmed by total organic carbon (TOC) and dechlorination analyses. The main intermediate products such as tetrachlorocatechol, tetrachlorohydroquinone, acetic acid, formic acid, ...

2010-04-15

466

Euryarchaeal ?-CASP Proteins with Homology to Bacterial RNase J Have 5?- to 3?-Exoribonuclease Activity*  

UK PubMed Central (United Kingdom)

In the Archaea only a handful of ribonucleases involved in RNA processing and degradation have been characterized. One potential group of archaeal ribonucleases are homologues of the bacterial RNase...Full Text Available

2010-06-04

467

Engineering of a psychrophilic bacterium for the bioremediation of aromatic compounds  

UK PubMed Central (United Kingdom)

Microbial degradation of aromatic hydrocarbons has been studied with the aim of developing applications for the removal of toxic compounds. Efforts have been directed toward the genetic manipulation...Full Text Available

2010-05-01

468

Degradation of the Ferric Chelate of EDTA by a Pure Culture of an Agrobacterium sp  

UK PubMed Central (United Kingdom)

A pure culture of an Agrobacterium sp. (deposited as ATCC 55002) that mineralizes the ferric chelate of EDTA (ferric-EDTA) was isolated by selective enrichment from a treatment facility...Full Text Available

1990-11-01

469

Degradation mechanisms of nylon separator materials for a nickel-cadmium cell in KOH electrolytes  

Energy Technology Data Exchange (ETDEWEB)

Degradation reactions of a nylon 6 battery separator material have been studied in 4-34% aqueous KOH electrolytes at 35/sup 0/-110/sup 0/C. In a Ni/Cd cell, this degradation involves a slow hydrolysis reaction followed by fast electrochemical oxidations of the hydrolysis reaction products. Arrhenius activation energy of the hydrolysis reaction in 34% KOH was 20.0 +- 0.3 kcal/mole. A plot of the hydrolysis rate at 100/sup 0/C vs. hydroxyl ion concentration gave a rate maximum at about 16% KOH, and the mechanism for this effect is discussed. Electrochemical oxidations of the hydrolysis product, 6-aminocaproate ion, appear to proceed rapidly in several sequential steps at a nickel oxide electrode. In a Ni/Cd cell, the combination of nylon separator hydrolysis followed by electrochemical oxidation of the products can seriously degrade the battery lifetime. The rate of the hydrolysis of nylon 66 separator material was ...

1989-03-01

470

Cloning and sequencing of a dehalogenase gene encoding an enzyme with hydrolase activity involved in the degradation of gamma-hexachlorocyclohexane in Pseudomonas paucimobilis.  

UK PubMed Central (United Kingdom)

In Pseudomonas paucimobilis UT26, gamma-hexachlorocyclohexane (gamma-HCH) is converted by two steps of dehydrochlorination to a chemically unstable intermediate, 1,3,4,6-tetrachloro-1,4-cyclohexadiene...Full Text Available

1993-10-01

471

Cloning and Sequencing of a Novel meta-Cleavage Dioxygenase Gene Whose Product Is Involved in Degradation of ?-Hexachlorocyclohexane in Sphingomonas paucimobilis  

UK PubMed Central (United Kingdom)

Sphingomonas (formerly Pseudomonas) paucimobilis UT26 utilizes γ-hexachlorocyclohexane (γ-HCH), a halogenated organic insecticide,...Full Text Available

1999-11-01

472

Cloning and Sequencing of a 2,5-Dichlorohydroquinone Reductive Dehalogenase Gene Whose Product Is Involved in Degradation of ?-Hexachlorocyclohexane by Sphingomonas paucimobilis  

UK PubMed Central (United Kingdom)

Sphingomonas (formerly Pseudomonas) paucimobilis UT26 utilizes γ-hexachlorocyclohexane (γ-HCH), a halogenated organic insecticide,...Full Text Available

1998-03-01

473

Cloning and Characterization of lin Genes Responsible for the Degradation of Hexachlorocyclohexane Isomers by Sphingomonas paucimobilis Strain B90  

UK PubMed Central (United Kingdom)

Hexachlorocyclohexane (HCH) has been used extensively against agricultural pests and in public health programs for the control of mosquitoes. Commercial formulations of HCH consist of a mixture of four...Full Text Available

2002-12-01

474

Cellulase-Xylanase Synergy in Designer Cellulosomes for Enhanced Degradation of a Complex Cellulosic Substrate  

UK PubMed Central (United Kingdom)

Designer cellulosomes are precision-engineered multienzyme complexes in which the molecular architecture and enzyme content are exquisitely controlled. This system was used to examine enzyme cooperation...Full Text Available

475

Boron-Dependent Degradation of NIP5;1 mRNA for Acclimation to Excess Boron Conditions in Arabidopsis.  

Science.gov (United States)

Boron (B) is an essential plant micronutrient that is toxic at higher levels. NIP5;1 is a boric acid channel required for B uptake and growth under B deficiency. Accumulation of the NIP5;1 transcript is upregulated under B deficiency in Arabidopsis thaliana roots. To elucidate the mechanism of regulation, the 5' untranslated region (UTR) of NIP5;1 was tested for its ability to confer B-dependent regulation using ?-glucuronidase and green fluorescent protein as reporters. This analysis showed that the 5' UTR was involved in NIP5;1 transcript accumulation in response to B conditions. We also found that high-B conditions trigger NIP5;1 mRNA degradation and that the sequence from +182 to +200 bp in the 5' UTR is required for this mRNA destabilization. In the nip5;1-1 mutant background, a NIP5;1 complementation construct without the 5' UTR produced high levels of mRNA accumulation, increased B concentrations in tissues, and reduced growth under high-B conditions. These ...

2011-09-01

476

Biological processing and interactions with coal: Summary of activities for the period January 1, 1988--March 31, 1988  

Science.gov (United States)

Biodegradation/solubilization of coal is described. The degradation of dibenzothiophene by two bacterial strains is reported. The effects of adding salicylate to the treatments was also investigated. 2 figs., 5 tabs. (CBS)

1988-01-01

477

Autophosphorylation Within the Atg1 Activation Loop Is Required for Both Kinase Activity and the Induction of Autophagy in Saccharomyces cerevisiae  

UK PubMed Central (United Kingdom)

Autophagy is an evolutionarily conserved degradative pathway that has been implicated in a number of physiological events important for human health. This process was originally identified as a response...Full Text Available

2010-07-01

478

Assessing phytoremediation potentials of selected tropical plants for acrylamide  

Science.gov (United States)

In biotechnology, acrylamide is being used in DNA and RNA analysis using the polyacrylamide gel electrophoreses procedure. Polymerized acrylamide is degraded into acrylamide through time; it is converted into a hazardous contaminant that is carcinogenic and neurotoxic to animals and humans. Because ...

479

Aging mechanism of Sulfonated poly(aryl ether ketone) (sPAEK) in an hydroperoxide solution and in fuel cell  

Energy Technology Data Exchange (ETDEWEB)

Ex situ and in situ fuel cell degradation of a sPAEK membrane were investigated. Post-mortem analyses of the aged membrane and of the degradation products eluted in water were carried out by NMR, IR, SEC and EDX. Ex situ agings were performed in a low concentration H{sub 2}O{sub 2} solution (0.07%) without any metallic catalyst. We exemplify that ex situ accelerated aging tests in such hydrogen peroxide solution are relevant to the chemical degradation in fuel cell. We have shown that a 500 h fuel cell test at moderate temperature (60 C) induces significant modifications on the macromolecules such as a 40% molecular weight reduction. Degradation appears heterogeneous and limited to the cathode side. The model compound approach developed in the previous article (Perrot et al.) has allowed the identification of the aging path in fuel cell. Phenolic and carboxylic acid chain ends have been identified as ...

2010-01-15

480

Superconductivity in irradiated A-15 compounds at low fluences. I. Neutron-irradiated V_3Si  

International Nuclear Information System (INIS)

The behavior of the superconducting transition temperature T/sub c/ of single-crystal and polycrystalline V_3Si was investigated as a function of low-fluence neutron irradiation. It is found that the initial degradation of T/sub c/ is sample-dependent, some specimens showing no degradation in T/sub c/ up to a fluence of 2 x 10"1"8 n/cm"2. This and many other earlier observations on low-fluence behavior are explained in terms of a recently proposed model of radiation damage in A-15 compounds.

481

Radiation hardening characterization of a VDMOS developed at CAS institute of microelectronics  

International Nuclear Information System (INIS)

Total dose irradiation effects on a VDMOS developed at Institute of Microelectronics, CAS were investigated, particularly the electric parameter changes under different bias conditions. It was found that the breakdown voltage degradation by the irradiation depended mainly on the drain bias, whereas the threshold voltage degradation depended mainly on the gate bias. Thus, an innovative and effective method to domestic VDMOS total dose ionization characterization is that threshold voltage radiation hardening characterization should be tested on gate bias condition, and the breakdown voltage radiation hardening characterization, be tested on the drain bias. (authors)

2008-08-01

482

Non-thermal plasma destruction of allyl alcohol in waste gas: kinetics and modelling  

International Nuclear Information System (INIS)

Non-thermal plasma treatment is a promising technique for the destruction of volatile organic compounds in waste gas. A relatively unexplored technique is the atmospheric negative dc multi-pin-to-plate glow discharge. This paper reports experimental results of allyl alcohol degradation and ozone production in this type of plasma. A new model was developed to describe these processes quantitatively. The model contains a detailed chemical degradation scheme, and describes the physics of the plasma by assuming that the fraction of electrons that takes part in chemical reactions is an exponential function of the reduced field. The model captured the experimental kinetic data to less than 2 ppm standard deviation.

2008-02-01

483

Infrared spectroscopy analysis of MgO-doped silicon nitride  

Energy Technology Data Exchange (ETDEWEB)

Silicon nitride hybrid ball bearings used in high temperature applications undergo mechanical and environmental degradation. To study the surface chemistry of silicon nitride, a CAChe{trademark} Worksystem* has been used to generate the clusters and corresponding transmission vibrational spectra of silicon nitride. In the present study, the effect of surface conditions on the surface chemistry and wear degradation of silicon nitride was evaluated. Infrared reflection spectroscopy (IRRS) used to determine molecular orientations shows a difference in reflectance spectra for fractured and as-received.

1997-12-31

484

Inactivation of aflatoxin B1 by using the synergistic effect of hydrogen peroxide and gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

Inactivation of aflatoxin B1 was studied by using gamma radiation and hydrogen peroxide. A 100-krad dose of gamma radiation was sufficient to inactivate 50 micrograms of aflatoxin B1 in the presence of 5% hydrogen peroxide, and 400 krad was required for total degradation of 100 micrograms of aflatoxin in the same system. Degradation of aflatoxin B1 was confirmed by high-pressure liquid chromatographic and thin-layer chromatographic analysis. Ames microsomal mutagenicity test showed loss of aflatoxin activity. This method of detoxification also reduces the toxin levels effectively in artificially contaminated groundnuts.

1989-02-01

485

Complex radiation degradation behaviour of PVC materials under accelerated aging conditions  

International Nuclear Information System (INIS)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the levelling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests. (author).

1982-10-01

486

Complex radiation degradation behavior of PVC materials under accelerated aging conditions  

Energy Technology Data Exchange (ETDEWEB)

The radiation degradation behavior of three commercial polyvinyl chloride (PVC) materials has been investigated. All three exhibit an interesting reversal in the trend of the tensile strength part way through the aging experiment: the tensile strength first drops, then rises. The early drop is associated with oxidative scission; the rise is associated with crosslinking and is preceded by the material reaching the gel point. It was also found that the tensile elongation tended to level out in advanced stages of aging with the leveling-out values dependent on the dose rate. These phenomena pose complications for the design of accelerated aging tests.

1983-07-01

487

Reference scenarios for deforestation and forest degradation in support of REDD: a review of data and methods  

Energy Technology Data Exchange (ETDEWEB)

Global climate policy initiatives are now being proposed to compensate tropical forest nations for reducing carbon emissions from deforestation and forest degradation (REDD). These proposals have the potential to include developing countries more actively in international greenhouse gas mitigation and to address a substantial share of the world's emissions which come from tropical deforestation. For such a policy to be viable it must have a credible benchmark against which emissions reduction can be calculated. This benchmark, sometimes termed a baseline or reference emissions scenario, can be based directly on historical emissions or can use historical emissions as input for business as usual projections. Here, we review existing data and methods that could be used to measure historical deforestation and forest degradation reference scenarios including FAO (Food and Agricultural Organization of the United Nations) national statistics ...

2008-04-15

488

Reference scenarios for deforestation and forest degradation in support of REDD: a review of data and methods  

International Nuclear Information System (INIS)

Global climate policy initiatives are now being proposed to compensate tropical forest nations for reducing carbon emissions from deforestation and forest degradation (REDD). These proposals have the potential to include developing countries more actively in international greenhouse gas mitigation and to address a substantial share of the world's emissions which come from tropical deforestation. For such a policy to be viable it must have a credible benchmark against which emissions reduction can be calculated. This benchmark, sometimes termed a baseline or reference emissions scenario, can be based directly on historical emissions or can use historical emissions as input for business as usual projections. Here, we review existing data and methods that could be used to measure historical deforestation and forest degradation reference scenarios including FAO (Food and Agricultural Organization of the United Nations) national statistics and ...

489

Eddy current signal analysis techniques for assessing degradation of support plate structures in nuclear steam generators  

Energy Technology Data Exchange (ETDEWEB)

The steam generator (SG) is one of the most critical components of the heat transfer system in nuclear generation stations. Testing the structural integrity of SG tubing and SG internals is a key element of the fitness-for-service assessments to assure the safe and continuous operation of nuclear power plants. Recent eddy current (ET) inspections of two nuclear power plants revealed degradation of some of the tube support plate (TSP) structures, which was also confirmed by visual inspection. The phenomena was described as metal loss, caused by flow-accelerated corrosion of the carbon steel trefoil support plate and varying from minor to complete loss of the ligaments. This loss of TSP ligaments results in lack of support for the adjacent tubes making them more susceptible to fretting-wear damage and fatigue cracking. A signal analysis method, based on the responses at low frequency of two types of eddy current probes, has been developed to assess the degree of ...

2006-07-01

490

Use of DNA probes to study tetracycline resistance determinants in gram-negative bacteria from swine  

Energy Technology Data Exchange (ETDEWEB)

Specific {sup 32}P-labeled DNA probes were prepared and used to evaluate the distribution of tetracycline resistance determinants carried by gram-negative enteric bacteria isolated from pigs in 3 swine herds with different histories of antibiotic exposure. Plasmid DNA, ranging in size from 2.1 to 186 Kb, was observed in over 84% of 114 isolates studied. Two of 78 tetracycline resistant strains did not harbor plasmids. The DNA probes were isolated from plasmids pSL18, pRT29/Tn10, pBR322 and pSL106, respectively, and they represented class A, B, C and D tetracycline resistance determinants. Hybridization conditions using 0.5X SSPE at 65{degrees}C minimize cross-hybridization between the different class of tetracycline resistance genes. Cross-hybridization between class A and class C determinants could be distinguished by simultaneous comparison of the intensity of their hybridization signals. Plasmids from over 44% of the tetracycline resistant isolates did not ...

1989-01-01

491

Test of electron beam technology on Savannah River Laboratory low-activity aqueous waste for destruction of benzene, benzene derivatives, and bacteria  

Energy Technology Data Exchange (ETDEWEB)

High energy radiation was studied as a means for destroying hazardous organic chemical wastes. Tests were conducted at bench scale with a {sup 60}Co source, and at full scale (387 l/min) with a 1.5 MV electron beam source. Bench scale tests for both benzene and phenol included 32 permutations of water quality factors. For some water qualities, as much as 99.99% of benzene or 90% of phenol were removed by 775 krads of {sup 60}Co irradiation. Full scale testing for destruction of benzene in a simulated waste-water mix showed loss of 97% of benzene following an 800 krad dose and 88% following a 500 krad dose. At these loss rates, approximately 5 Mrad of electron beam irradiation is required to reduce concentrations from 100 g/l to drinking water quality (5 {mu}g/l). Since many waste streams are also inhabited by bacterial populations which may affect filtering operations, the effect of irradiation on those populations was also studied. {sup 60}Co and electron beam irradiation were both ...

1993-08-01

492

Synthesis, characterization and biological evaluation of mononuclear Co(II), Ni(II), Cu(II) and Pd(II) complexes with new N2O2 Schiff base ligands.  

Science.gov (United States)

New tetradentate N(2)O(2) donor Schiff bases and their mononuclear Co(II), Ni(II), Cu(II), and Pd(II) complexes were synthesized and characterized extensively by IR, (1)H-, (13)C-NMR, mass, ESR, conductivity measurements, elemental and thermal analysis. Specifically the magnetic and electronic spectral measurements demonstrate the octahedral structures of cobalt(II), nickel(II) complexes and square planar geometries of copper(II), palladium(II) complexes. All the ligands and complexes were screened for their in vitro antibacterial activity against two gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus) and two gram-negative bacteria (Escherichia coli, Klebsiella pneumonia). In this study, Pd(II) complexes exhibited potent antibacterial activity against B. subtilis, S. aureus whereas other metal complexes also exerted good activity towards all tested strains even than standard drugs streptomycin and ampicillin. PMID:21297294

2011-02-01

493

Influence of substrates on nitrogen removal performance and microbiology of anaerobic ammonium oxidation by operating two UASB reactors fed with different substrate levels.  

Science.gov (United States)

Both ammonium and nitrite act as substrates as well as potential inhibitors of anoxic ammonium-oxidizing (Anammox) bacteria. To satisfy demand of substrates for Anammox bacteria and to prevent substrate inhibition simultaneously; two strategies, namely high or low substrate concentration, were carefully compared in the operation of two Anammox upflow anaerobic sludge blanket (UASB) reactors fed with different substrate concentrations. The reactor working at relatively low influent substrate concentration (NO(2)(-)-N, 240 mg-NL(-1)) was shown to avoid the inhibition caused by nitrite and free ammonia. Using the strategy of low substrate concentration, a record super high volumetric nitrogen removal rate of 45.24 kg-Nm(-3) day(-1) was noted after the operation of 230 days. To our knowledge, such a high value has not been reported previously. The evidence from transmission electron microscopy (TEM) showed that the morphology and ultrastructure of ...

2010-04-13

494

Gene discovery in the Acanthamoeba castellanii genome  

Energy Technology Data Exchange (ETDEWEB)

Acanthamoeba castellanii is a free-living amoeba found in soil, freshwater, and marine environments and an important predator of bacteria. Acanthamoeba castellanii is also an opportunistic pathogen of clinical interest, responsible for several distinct diseases in humans. In order to provide a genomic platform for the study of this ubiquitous and important protist, we generated a sequence survey of approximately 0.5 x coverage of the genome. The data predict that A. castellanii exhibits a greater biosynthetic capacity than the free-living Dictyostelium discoideum and the parasite Entamoeba histolytica, providing an explanation for the ability of A. castellanii to inhabit adversity of environments. Alginate lyase may provide access to bacteria within biofilms by breaking down the biofilm matrix, and polyhydroxybutyrate depolymerase may facilitate utilization of the bacterial storage compound polyhydroxybutyrate as a food source. Enzymes for the ...

2005-08-01

495

Development and application of bio-sensor. Production of ammonia sensor  

Energy Technology Data Exchange (ETDEWEB)

The objectives of this study are to make a biosensor on a trial basis which can instantaneously measure the nitrogen in wastewater, and to develop a wastewater treatment system which is capable of on-line measurement and controlling. The system provides easier operational control relating to such a high efficient treatment as the removal of nitrogen content in wastewater, serving as a solution to the eutrophication problem. It can be applied also to the analysis of fertilizer components for agriculture. Ammonia oxidizing bacteria were immobilized with cellulose acetate film, which is mounted on a diaphragm type oxygen electrode to make a sensor, and its responsibility was studied. The gradient is slow in high concentration but sharp in low concentration, and it seems possible to use it for the measurement for less than 20 ppm nitrogen concentration. The dependence of the sensor including electrodes and activity of bacteria on temperature is ...

1989-08-01

496

Antenna organization in green photosynthetic bacteria. Progress report, March 1986--February 1987  

Energy Technology Data Exchange (ETDEWEB)

This project is concerned with the structure and function of the unique antenna system found in the green photosynthetic bacteria. The antenna system in these organisms is contained within a vesicle known as a chlorosome, which is attached to the cytoplasmic side of the cell membrane. Additional antenna pigments and reaction centers are contained in integral membrane proteins. Energy absorbed by the bacteriochlorophyll c (BChl c) pigments in the chlorosome is transferred via a ``baseplate`` array of BChl a antenna pigments into the membrane and to the reaction center. This system is similar in some respects to the phycobilisome antenna system found in cyanobacteria and some types of algae, in that a membrane-associated structure absorbs light and transfers it to the membrane where conversion to chemical energy takes place. However, the overall structure, the type of pigments utilized and the nature of the proteins in these two types of membrane-associated antenna ...

1987-12-31

497

The effects of cefazolin on cirrhotic patients with acute variceal hemorrhage after endoscopic interventions  

British Library Electronic Table of Contents (United Kingdom)

Background The American Association for the Study of Liver Diseases (AASLD) guidelines recommend that antibiotic prophylaxis should be instituted in any patient with cirrhosis and gastrointestinal hemorrhage, and that oral norfloxacin, intravenous ciprofloxacin, and ceftriaxone are preferable. However, the antimicrobial spectrum of the first generation of cephalosporins (cefazolin) covers a wide range of bacteria species, including community-acquired strains of Escherichia coli and Klebsiella pneumoniae, but their efficacy as prophylactic antibiotics in cirrhotic patients with acute hemorrhage was seldom warranted in the literature. This study aimed to explore the effects of cefazolin on the outcome of cirrhotic patients with acute variceal hemorrhage after endoscopic interventions. Method...

2011-01-01

498

Effects of Acetate Competition, pH and Soil Structure on the Rates and Pathways of Methane Formation in Tropical Rain Forest Soils  

Science.gov (United States)

The C isotopic composition of CH4 emissions are strongly influenced by the pathway of CH4 formation. Contrary to data from other freshwater systems, soil gas and surface flux measurements made in the tropical rain forests of Puerto Rico strongly suggest that CH4 produced in these environments was derived from CO2 reduction, rather than from acetate consumption. This study explored the effects of bacterial competition for acetate, pH, and soil structure on the pathways of CH4 formation in tropical rain forest soils. Our goal was to test two principal hypotheses: (1) ferric iron-reducing bacteria out-competed methanogens for acetate, resulting in greater CO2 reduction rather than aceticlastic methanogenesis, and (2) the low pH of tropical rain forest soils favors CO2 reduction rather than aceticlastic methanogenesis. In addition, this study also investigated the effect of destroying soil aggregate structure on the pathways and rates of CH4 production. Ferric ...

2004-12-01

499

Antimicrobial potential of Glycyrrhiza glabra roots  

British Library Electronic Table of Contents (United Kingdom)

The present study was aimed to investigate antimicrobial potential of Glycyrrhiza glabra roots. Antimycobacterial activity of Glycyrrhiza glabra was found at 500mg/mL concentration. Bioactivity guided phytochemical analysis identified glabridin as potentially active against both Mycobacterium tuberculosis H37Ra and H37Rv strains at 29.16mg/mL concentration. It exhibited antimicrobial activity against both Gram-positive and Gram-negative bacteria. Our results indicate potential use of licorice as antitubercular agent through systemic experiments and sophisticated anti-TB assay.

2008-01-01

500

Acceleration of Emergence of Bacterial Antibiotic Resistance in Connected Microenvironments.  

Science.gov (United States)

The emergence of bacterial antibiotic resistance is a growing problem, yet the variables that influence the rate of emergence of resistance are not well understood. In a microfluidic device designed to mimic naturally occurring bacterial niches, resistance of Escherichia coli to the antibiotic ciprofloxacin developed within 10 hours. Resistance emerged with as few as 100 bacteria in the initial inoculation. Whole-genome sequencing of the resistant organisms revealed that four functional single-nucleotide polymorphisms attained fixation. Knowledge about the rapid emergence of antibiotic resistance in the heterogeneous conditions within the mammalian body may be helpful in understanding the emergence of drug resistance during cancer chemotherapy. PMID:21940899

2011-09-23