WorldWideScience
1

Method and composition for acidizing subterranean formations  

Energy Technology Data Exchange (ETDEWEB)

The present invention relates to a method of acidizing a subterranean formation or well bore employing an acidic solution containing a corrosion inhibitor composition comprising an inhibiting effective amount of an acetylenic alcohol, a quaternary ammonium compound, an aromatic hydrocarbon and an antimony compound.

1985-02-12

2

Extraction of americium of different oxidation states in two-phase aqueous system based on polyethylene glycol  

International Nuclear Information System (INIS)

Americium extraction in different oxidation states in two-phase aqueous system based on polyethylene glycol is investigated. Conditions for quantitative extraction of americium (3) and americium (5) from ammonium sulfate solutions within pH=3-5 interval in the presence of arsenazo 3 are found. Composition of the produced americium complexes with reagent is determined; americium (3) interacts with arsenazo 3 in ammonium sulfate solutions with the formation of MeR and Me_2R composition complexes. Absorption spectrum characteristics of americium (3) and- (5) complexes with arsenazo 3 in ammonium sulfate solutions and extracts based polyethylene glycol aqueous solutions are given. Molar extinction coefficients of americium complexes with arsenazo (3) in these solutions are determined.

1987-01-01

4

Radiation damage studies on CrO_4"2"- doped alums  

International Nuclear Information System (INIS)

Radiation damage studies have been carried out on undoped and CrO_4"2"- doped potassium and ammonium alums. The optical absorption bands observed around 27100 and 36500 cm"-"1 before irradiation have been attributed to the transitions t_1 #-># e and t_1 #-># t_2, on the basis of Ball-hausen and Liehr scheme. On prolonged X-irradiation, these bands disappear in both the alums and three new bands seem to grow in ammonium alum while only two new bands could be seen in potassium alum. EPR studies at RT reveal that there are two lines at g = 2.004 and g = 2.010 in ammonium alum and only one line at g = 2.004 in potassium alum. Besides these two nearly isotropic lines, there is a set of lines around g = 1.95 in both the alums. Correlating the optical and EPR studies it is concluded that SO_3"- and O_3"- centres have formed on X-irradiation in ammonium alum while only SO_3"- seems to have formed in ...

5

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 fumigants was significantly enhanced in soils amended with ammonium thiosulfate (ATS) and sodium diethyldithiocarbamate ...

6

Formation of complex Langmuir and Langmuir-Blodgett films of water soluble rosebengal  

British Library Electronic Table of Contents (United Kingdom)

This communication reports the formation of complex Langmuir monolayer at the air-water interface by charge transfer types of interaction with the water soluble N-cetyl Formula Not Shown -trimethyl ammonium bromide (CTAB) molecules doped with rosebengal (RB), with the stearic acid (SA) molecules of a preformed SA Langmuir monolayer. The reaction kinetics of the formation of RB-CTAB-SA complex monolayer was monitored by observing the increase in surface pressure with time while the barrier was kept fixed. Completion of interaction kinetics was confirmed by FTIR study. This complex Langmuir films at the air-water interface was transferred onto solid substrates at a desired surface pressure to form multilayered Langmuir-Blodgett films. Spectroscopic characterizations reveal some molecular lev...

2007-01-01

7

Some observations on amino acid racemization under pyrolytic temperatures and inorganic oxide-catalyzed intermolecular condensation.  

Science.gov (United States)

The problem of homochirality is of crucial importance for the origins of Life. While most laboratory studies are focused on the search of physical and chemical sources of handedness in the Universe, they reflect only one aspect of the problem: the origin of homochiral biomolecules. At the same time, any space environments where biomolecules are expected to form and where they have to pass through before the first primitive forms of Life emerge, include strong irradiation or/and high temperatures. This automatically implies the possibility of losing the optical activity, i.e. racemization. The simulation experiments performed by our group deal with the following two aspects of amino acid abiotic chemistry: (1) amino acid pyrolysis associated with their extraterrestrial delivery; and (2) peptide formation from amino acids catalyzed by inorganic oxides. According to our observations, the racemization phenomena are very common in the systems ...

2001-01-01

8

Processing and characterization of polyethylene/Brazilian clay nanocomposites  

Energy Technology Data Exchange (ETDEWEB)

Nanocomposites containing polyethylene (PE) and montmorillonite clay organically modified (OMMT) with quaternary ammonium salts were obtained via direct melt intercalation. A montmorillonite sample from the Brazilian state of Paraiba was treated with four different types of quaternary ammonium salts. After the treatment, the powder was characterized by X-ray diffraction and scanning electron microscopy. The dispersion and morphologies of OMMT within PE were investigated by X-ray diffraction and transmission electron microscopy. The results revealed the formation of intercalated montmorillonite layers in the PE matrix. The thermal stability and flammability of the PE/montmorillonite clay nanocomposites were measured by thermogravimetry and horizontal burning tests for HB classification, Underwrites Laboratories (UL 94), respectively. It was shown that the samples do not degrade at the processing temperature. By adding only 3 ...

2007-02-15

9

Subcellular localization of ammonium transporters in Dictyostelium discoideum  

UK PubMed Central (United Kingdom)

BackgroundWith the exception of vertebrates, most organisms have plasma membrane associated ammonium transporters which primarily serve to import a source of nitrogen for nutritional...Full Text Available

10

Formation and stabilization of anionic metal complexes in concentrated aqueous quaternary ammonium salt solutions  

Energy Technology Data Exchange (ETDEWEB)

Anionic complexes of transition metals were stabilized in aqueous solutions containing high concentrations of various short-chain quaternary ammonium salts. Compounds with longer paraffin chains were effective in much less concentrated solution. Complex ions were detected spectrophotometrically. FeCl/sub 4//sup -/, which is usually formed in concentrated HCl, was the predominant Fe(III) complex in 30 m choline chloride containing only 0.12 M HCl. A yellow transitory Tc(VII) chloro-addition intermediate, formed in the reduction of TcO/sub 4//sup -/ by concentrated HCl, was stabilized when the solution also contained 25 m choline chloride. Its spectrum, as well as the isolation of an already known Tc(VII) bipyridyl complex, is reported. Concentrated organic electrolytes also stabilized Tc(V) oxide halides against disproportionation and Tc(IV) hexahalides against hydrolysis. Halochromates of Cr(VI) were formed and stabilized in dilute acid containing quaternary ...

1985-02-04

11

Duplex surface treatment of AISI 1045 steel via plasma nitriding of chromized layer  

British Library Electronic Table of Contents (United Kingdom)

In this work AISI 1045 steel were duplex treated via plasma nitriding of chromized layer. Samples were pack chromized by using a powder mixture consisting of ferrochromium, ammonium chloride and alumina at 1273K for 5h. The samples were then plasma-nitrided for 5h at 803K and 823K, in a gas mixture of 75%N2+25%H2. The treated specimens were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis and Vickers micro-hardness test. The thickness of chromized layer before nitriding was about 8mm and it was increased after plasma nitriding. According to XRD analysis, the chromized layer was composed of chromium and iron carbides. Plasma nitriding of chromized layer resulted in the formation of chromium and iron nitrides and carbides. The hardness of the duplex layer...

2011-01-01

12

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

13

Obtainment of lanthanum oxide by fractionated precipitation method  

International Nuclear Information System (INIS)

... ammonium compounds benzilic acid chemical preparation lanthanum oxides

1979-01-01

14

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

15

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

16

Importance of eelgrass early life history stages in response to oyster aquaculture disturbance  

Science.gov (United States)

Aquaculture is increasing worldwide, however we have little understanding of its impacts on marine communities. A critical element of many marine communities are seagrasses, a group of globally distributed marine angiosperms that are drivers of many abiotic and biotic processes in estuarine and mari...

17

Glossary - Helmholtz-Centre for Environmental Research - UFZ - Research for the environment  

Wastenet

... Contrary to this definition, abiotic environmental factors are those in which no organisms participate - e.g. the geological underground, light, temperature and heat. Biotope The biotope is an area of uniform environmental conditions providing living place for a specific assemblage of plants and animals....

18

Ectopic Expression of Constitutively Activated RACB in Barley Enhances Susceptibility to Powdery Mildew and Abiotic Stress1  

UK PubMed Central (United Kingdom)

Small RAC/ROP-family G proteins regulate development and stress responses in plants. Transient overexpression and RNA interference experiments suggested that the barley (Hordeum vulgare)...Full Text Available

2005-09-01

19

Manganese removal from mine waters - investigating the occurrence and importance of manganese carbonates  

International Nuclear Information System (INIS)

Manganese is a common contaminant of mine water and other waste waters. Due to its high solubility over a wide pH range, it is notoriously difficult to remove from contaminated waters. Previous systems that effectively remove Mn from mine waters have involved oxidising the soluble Mn(II) species at an elevated pH using substrates such as limestone and dolomites. However it is currently unclear what effect the substrate type has upon abiotic Mn removal compared to biotic removal by in situ micro-organisms (biofilms). In order to investigate the relationship between substrate type, Mn precipitation and the biofilm community, net-alkaline Mn-contaminated mine water was treated in reactors containing one of the pure materials: dolomite, limestone, magnesite and quartzite. Mine water chemistry and Mn removal rates were monitored over a 3-month period in continuous-flow reactors. For all substrates except quartzite, Mn was removed from the mine water during this period, ...

2006-08-01

20

Use of carbon stable isotope to investigate chloromethane formation in the electrolytic dechlorination of trichloroethylene  

International Nuclear Information System (INIS)

Carbon stable isotope trichloroethylene ("1"3C TCE) was used to investigate the formation of chloromethane (CM) during the electrolytic dechlorination of trichloroethylene (TCE) at a granular-graphite packed cathode. A method was developed to use a conventional GC/MS to analyze and quantify regular and "1"3C TCE and their dechlorination products. The concentration of a "1"3C compound can be calculated, based on the concentration of its regular counterpart, from the response ratio of two fragments of different mass per charge values from the compounds in a sample and two characteristic MS spectrum ratios: one is the response ratio of the two fragments of the regular compound, and the other is the response ratio of the corresponding fragments of the regular and "1"3C compounds at the same concentrations. The method was used to analyze the regular and "1"3C compounds observed in an experiment of dechlorination in an ammonium acetate solution that ...

2007-03-22

21

Tanana River Floodplain Dissolved Organic Nitrogen (DON) Budget, GPS coordinates for Tanana River Floodplain study plots  

Science.gov (United States)

Ammonium, Nitrate, and Amino Acid concentrations in .5M K2SO4 extracted T0 Tanana Floodplain soils Ammonium, Nitrate, and Amino Acid concentrations in . ... ...

22

Process and apparatus for chemically removing ash from coal  

Science.gov (United States)

Finely divided ash-containing coal is immersed in an aqueous solution of hydrochloric acid or citric acid, and acidic ammonium fluoride to cause the ash to react with the acid and the acidic ammonium fluoride, and the deashed coal is thereafter separated from the solution.

1984-01-03

23

Determining insoluble impurities in spent sulfuric acid from the production of synthetic alcohols  

Energy Technology Data Exchange (ETDEWEB)

Ammonium sulfate is produced from spent sulfuric acid from the production of alcohols. Certain mineral and organic impurities exist in the sulfuric acid that impair the quality of the ammonium sulfate. A detailed method for the chemical analysis for the impurities is presented.

1983-01-01

24

Adverse Effect of Ammonium Salts on the Antibacterial Activity of Paraformaldehyde Solutions  

UK PubMed Central (United Kingdom)

The antibacterial activity of aqueous solutions of paraformaldehyde in concentrations from 0.1 to 0.4% (w/v) is bacteriostatic rather than bactericidal in the presence or absence of ammonium chloride....Full Text Available

1963-07-01

25

Application of the exergy method to environmental impact estimation: The ammonium nitrate production as a case study  

Energy Technology Data Exchange (ETDEWEB)

The exergy method is used to compare different production processes and various methods for emission abatement with respect to their overall environmental impact. Some ammonium nitrate production processes are studied as examples, because the pollutants (ammonia and ammonium nitrate), emitted from these processes into the air and/or into the water, are really a feedstock and a product from the production process. Therefore, the essential result of the waste flows treatment is the recycling of the pollutants (ammonia and ammonium nitrate) back into the production process, decreasing simultaneously the exergy input and cumulative exergy consumption. (author)

2010-08-15

26

Analysis of S-adenosylmethionine and related sulfur metabolites in bacterial isolates of Pseudomonas aeruginosa (BAA-47) by liquid chromatography/electrospray ionization coupled to a hybrid linear quadrupole ion trap and Fourier transform ion cyclotron resonance mass spectrometry  

British Library Electronic Table of Contents (United Kingdom)

A comprehensive and highly selective method for detecting in bacterial supernatants a modified sulfur nucleoside, S-adenosyl-L-methionine (SAM), and its metabolites, i.e., S-adenosylhomocysteine (SAH), adenosine (Ado), 5prime-deoxy-5prime-methylthioadenosine (MTA), adenine (Ade), S-adenosyl-methioninamine (dcSAM), homocysteine (Hcy) and methionine (Met), was developed. The method is based on reversed-phase liquid chromatography with positive electrospray ionization (ESI+) coupled to a hybrid linear quadrupole ion trap (LTQ) and 7-T Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS). A gradient elution was employed with a binary solvent of 0.05 M ammonium formate at pH 4 and acetonitrile. The assay involves a simultaneous cleanup of cell-free bacterial broths by solid-pha...

2009-01-01

27

Primary productivity C-14 and algal assay in the study of water pollution effects in the Citarum River and Jatiluhur Reservoir  

International Nuclear Information System (INIS)

Water quality of the Citarum River and the Jatiluhur Reservoir in Indonesia was evaluated using C-14 radioisotope. A close relationship between the abiotic (physical and chemical) and the biotic (algal growth potential, primary productivity, chlorophylla and diversity index of planktonic and benthic macroinvertebrate) parameters was obtained. Algal growth potential to abiotic parameters relationship has the highest correlation coefficient and can be used as a pollution indicator. The other biotic parameters do not show clear relationship with the abiotic parameters. The Citarum water quality is the lowest in those locations which receive human and industrial waste from Bandung and its environment. This water cannot be used for drinking purposes and fishery. The water quality in other locations of the river, however, meets the criteria for agriculture. Agricultural waste does not show any drastic effect on the water quality ...

1983-03-01

28

Comparative Uptake and Interaction of Several Radionuclides in the Trophic Levels Surrounding the Los Alamos Meson Physics Facility (LAMPF) Waste Water Ponds.  

Science.gov (United States)

A study was undertaken to examine the uptake, distribution, and interaction of five activation products (Co-57, Be-7, Cs-134, Rb-83, and Mn-54) within the biotic and abiotic components surrounding the waste treatment lagoons of the Los Alamos Meson Physic...

1989-01-01

29

Zhdanovka coking chemists and agriculture  

Energy Technology Data Exchange (ETDEWEB)

The Zhdanovka Coking Plant supplies materials for commercial use, e.g. ammonium sulfate and colloidal sulfur for agriculture and road-cementing materials. The method used for the production of colloidal sulfur is described briefly.

1984-01-01

31

System for cooling primary gas coolers using return water stabilized by means of ammonium sulfate  

Energy Technology Data Exchange (ETDEWEB)

Discusses scaling of closed systems for cooling coal gas from black coal coking. Scaling rate and factors that influence scaling are analyzed. Physical and chemical properties of scale buildup on the inner walls of pipe cooling systems are evaluated. Water pH value and its effects on scaling and solubility of chemical compounds that form scale are discussed. Use of ammonium sulfate for scale control is analyzed. Consumption rate of ammonium sulfate depends on ambient temperature, water pH value and chloride content in return water. Formulae for calculating optimum content of ammonium sulfates for scale control are derived. 3 refs.

1989-08-01

32

Summaries of Competitive Food Defense Research Reports, 2005  

Science.gov (United States)

... The least effective disinfectant was CTACl, which is a quaternary ammonium surfactant similar to those used in common household disinfectants. ...

33

Metal phthalocyanine catalysts  

Energy Technology Data Exchange (ETDEWEB)

As a new composition of matter, alkali metal or ammonium or tetraalkylammonium diazidoperfluorophthalocyanatoferrate. Other embodiments of the invention comprise compositions wherein the metal of the coordination complex is cobalt, manganese and chromium.

1994-01-01

34

Induction and Repression of Nitrate Reductase in Neurospora crassa  

UK PubMed Central (United Kingdom)

Synthesis of wild-type Neurospora crassa assimilatory nitrate reductase is induced in the presence of nitrate ions and repressed in the presence of ammonium ions. Effects of several...Full Text Available

1978-02-01

35

EVALUATION OF AMMONIUM NITRATE, ALUMINUM ...  

Science.gov (United States)

... 24 5 Exploding Bridgewire Test Vehicle.... . 0..... 25 ... 18 7 Results of Exploding Bridgewire TestLng of TP-41 and TP-41 Mixtures ..... ...

1964-05-14

36

Formation of double hafnium sulfates in the systems HfO"2-H"2SO"4-Me"2SO"4-H"2O (Me-Na, K, Rb, Cs and NH"4)  

International Nuclear Information System (INIS)

Influence of alkali elements on formation, composition, solubility and region of stability of complex hafnium sulfates, separated in the HfO"2-H"2SO"4-Me"2SO"4-H"2O (Me-Na, K, Rb, Cs and NH"4 group) systems is studied. In all cases hafnium forms the complex sulfates of three types differing by basicity or ratio HfO"2:SO"3 1:1, 1:1.5, 1:2. Three basic and three medium sulfates are crystallized in the systems with sodium; with rubidium, cesium and ammonium - two basic and two medium sulfates and with potassium - two basic and one medium salts. Anhydrous salts do not form in the investigated systems. Potassium salt approximately 0.3% according to HfO"2 is characterized by minimum solubility from the salts of 2HfOSO"4x(1-3)Me"2SO"4x(4-6)xH"2O while solubility of the same salts with rubidium, cesium and sodium increases from (0.25-1.0); (0.5-1.5) till (1.0-5)% according to HfO"2 correspondingly.

1982-01-01

37

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

38

AMMONIA ABSORPTION/AMMONIUM BISULFATE REGENERATION PILOT PLANT FOR FLUE GAS DESULFURIZATION  

Science.gov (United States)

The report gives results of a pilot-plant study of the ammonia absorption/ammonium bisulfate regeneration process for removing SO2 from the stack gas of coal-fired power plants. Data were developed on the effects of such operating variable in the absorption of SO2 by ammoniacal l...

39

A precise structure redetermination of nickel ammonium sulfate hexahydrate, Ni(H_2O)_6.2NH_4.2SO_4  

International Nuclear Information System (INIS)

The Ni(H_2O)_6 ion is located at an inversion center. Six octahedral water molecules surround the Ni"I"I ion and form hydrogen bonds with the sulfate groups. Each ammonium group binds to the sulfate groups through hydrogen bonds. (orig.).

1994-05-01

40

Abiotic systems for the catalytic treatment of solvent-contaminated water  

Energy Technology Data Exchange (ETDEWEB)

Three abiotic systems are described that catalyze the reductive dehalogenation of heavily halogenated environmental pollutants, including carbon tetrachloride, trichloroethene, and perchloroethene. These systems include (a) an electrolytic reactor in which the potential on the working electrode (cathode) is fixed by using a potentiostat, (b) a light-driven system consisting of a semiconductor and (covalently attached) macrocycle that can accept light transmitted via an optical fiber, and a light-driven, two-solvent (isopropanol/acetone) system that promotes dehalogenation reactions via an unknown mechanism. Each is capable of accelerating reductive dehalogenation reactions to very high rates under laboratory conditions. Typically, millimolar concentrations of aqueous-phase targets can be dehalogenated in minutes to hours. The description of each system includes the elements of reaction mechanism (to the extent known), typical kinetic data, and a discussion of the ...

1996-12-31

41

Analysis of acidic compound classes in crude oil by negative ion electrospray ionization high resolution FT-ICR mass spectrometry  

Energy Technology Data Exchange (ETDEWEB)

Acidic constituents in crude oil are associated with the formation of stable emulsions during production and present a challenge for efficient oil recovery and processing. Acid molecules, including naphthenic acids and acidic sulfur in crude oil cause corrosion in refineries and pipelines. Naphthenic acids are also significant because of their surface activity and marginal water solubility, so that they may leach to wastewaters and cause adverse environmental effects. Acidic components of oil are not limited to carboxylic acids but also molecules that contain sulfur and nitrogen. As such, an improved understanding of the chemistry and physics of petroleum at the molecular level is needed in order to understand the range of problems associated with acidic oil components and to design better solutions. The applications of negative-ion electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) for speciation of acidic oil ...

2008-07-01

42

Studies on the separation of Ag(I) during the recovery of Pu by ammonium plutonium(III) oxalate precipitation methodology  

International Nuclear Information System (INIS)

Studies on the separation of Ag(I) during the recovery of Pu from analytical waste generated during potentiometric determination of Pu using AgO as oxidant, by precipitation of Pu as ammonium plutonium (III) oxalate have shown that most of the Ag(I) is separated during the reduction of Pu to Pu(III) state by ascorbic acid. A decontamination factor of 54 was obtained. Additional a decontamination factor of 5.8 was obtained during the precipitation of Pu as ammonium plutonium (III) oxalate. The Ag content was determined by gamma spectrometry, using "1"1"1Ag as a tracer (T_1_/_2 7.45 d, #gamma# 342.1 keV) and HPGe as detector. The studies indicate that Ag is preferentially separated almost quantitatively during the recovery of plutonium, when acidity adjustment is done with NaOH instead of NH_3. (author)

2007-02-14

43

Prevention of chain cleavage in the chemical synthesis of 2'-silylated oligoribonucleotides.  

UK PubMed Central (United Kingdom)

Strong aqueous ammonium hydroxide used to remove N-acyl protecting groups from synthetic oligoribonucleotides causes removal of some alkylsilyl protecting groups from 2'-hydroxyls and leads to chain...Full Text Available

1989-05-11

44

Dietary Ammonium Chloride for the Acidification of Mouse Urine  

UK PubMed Central (United Kingdom)

A novel therapeutic compound was found to induce bladder tumors in male rats. Given the location of the tumors and the increased amounts of calcium- and magnesium-containing solids found in the urine...Full Text Available

2009-03-01

45

Development and testing of a technology for insulating influx of stratum waters into producing wells with the use of a copolymer of methacrylic acid and diethyl ammonium salt  

Energy Technology Data Exchange (ETDEWEB)

Cited are the results of physico-chemical studies and industrial tests of a copolymer of methacrylic acid and diethylammonium salt, used for limiting the influx of stratum waters into a well.

1981-01-01

46

Cation Involvement in Telomestatin Binding to G-Quadruplex DNA  

UK PubMed Central (United Kingdom)

The binding mode of telomestatin to G-quadruplex DNA has been investigated using electrospray mass spectrometry, by detecting the intact complexes formed in ammonium acetate. The mass measurements show...Full Text Available

47

Ammonium and Nitrate Uptake by the Floating Plant Landoltia punctata  

UK PubMed Central (United Kingdom)

Background and AimsPlants from the family Lemnaceae are widely used in ecological engineering projects to purify wastewater and eutrophic water bodies. However, the biology of nutrient...Full Text Available

2007-02-01

48

Impedance spectroscopy study with H-doped ammonium uranylphosphate self supported membranes  

International Nuclear Information System (INIS)

Equivalent circuit and electrical parameters for H-doped NH_4UO_2PO_4.3H_2O self supported membranes have been determined by impedance spectroscopy. The measurements were carried out with a dry membrane, at different temperatures, and a wet membrane in contact with different electrolyte solutions. Resistance values for the dry membrane decrease with temperature increase, which agrees with the weak protonic character of the H-doped ammonium uranylphosphate. On the other hand, differences in the electrical parameters, depending on the electrolyte considered were also obtained and are attributed to different conduction mechanisms. (Author).

49

Flue gas desulfurization. Rauchgasentschwefelung  

Energy Technology Data Exchange (ETDEWEB)

Low-dust flue gases can be washed efficiently of SO/sub 2/, and the flue gas heat can be utilized. The residual heat fraction still required by the process is characterized by a temperature of 15/sup 0/K above the temperature of the purified flue gas. Marketable crystalline ammonium sulfate is produced. The high efficiency and low heat consumption are achieved by combining all process stages in a single, fully integrated cycle process free of heat and materials losses. The process is characterized by high efficiency, low investment and operating costs, recovery of thermal energy, and production of an ammonium sulfate fertilizer.

1983-04-07

50

Emulsans. [Acinetobacter sp. ATCC 31012  

Energy Technology Data Exchange (ETDEWEB)

The production and uses are described for extracellular microbial polysaccharides (generically called emulsans) and for a new class of extracellular microbial protein-associated lipopolysaccharides (collectively called alpha-emulsans) produced by Acinetobacter Sp. ATCC 31012, its mutants or recombinants. Also included are the deproteinized lipopolysaccharides (collectively called apoemulsans) obtained from such emulsans, as well as to the divalent metal, ammonium, and quaternary ammonium salts of such emulsans and apoemulsans. The materials can be used (1) in cleaning oil-contaminated vessels used to transport or store crude oil or petroleum fractions in such a manner that the residual oil may be recovered for fuel value or for refining and (2) in enhanced oil recovery.

1983-07-05

51

Crystal structure of telluric acid ammonium phosphate (TAAP) in the paraelectric phase  

Energy Technology Data Exchange (ETDEWEB)

Crystal structure of monoclinic telluric acid ammonium phosphate (TAAP) has been studied by an X-ray diffraction method in the paraelectric phase at 333 K and in the ferroelectric phase at room temperature. It is confirmed that the space group in the paraelectric phase is P2/n. Comparison of the results between the two temperatures suggests that the plane which is made by the PO{sub 4} tetrahedron linked by hydrogen bonds has an important role for the ferroelectric phase transition. This plane is almost parallel to the direction of spontaneous polarization.

2005-01-15

52

Hydration of swelling clay and bacteria interaction. An experimental in situ reaction study; Hydratation des argiles gonflantes et influence des bacteries. Etude experimentale de reaction in situ  

Energy Technology Data Exchange (ETDEWEB)

This study reports on the physical-chemical behaviour of swelling di-octahedral clays (smectites) and their interaction with aqueous solutions and bacteria (Shewanella putrefaciens). Experimental results are presented for compacted clays, hydrated under confined volume conditions, using a new type of reaction-cell (the 'wet-cell' of Warr and Hoffman, 2004) that was designed for in situ X-ray diffraction (XRD) measurement. For comparison, dispersed clay systems were studied using standard batch solutions subjected to varying degrees of agitation. The combination of time-dependent in situ XRD measurements with gravimetric measurements and calculated diffraction patterns using the CALCMIX software (Plancon and Drits, 1999) allowed to successful quantification of the dynamics of water uptake and storage. This analytical procedure combined with published water vapour adsorption data enabled determination of the abundance of structured water layers, developed in the ...

2008-01-15

53

Influence of migrant tundra swans (Cygnus columbianus) and Canada geese (Branta canadensis) on aquatic vegetation at Long Point, Lake Erie, Ontario  

British Library Electronic Table of Contents (United Kingdom)

Numerous studies have shown that large, herbivorous waterfowl can reduce quantity of aquatic plants during the breeding or wintering season, but relatively few document herbivory effects at staging areas. This study was done to determine if feeding activities of tundra swans (Cygnus columbianus columbianus) and Canada geese (Branta canadensis) had a measurable additive influence on the amount of aquatic plants, primarily muskgrass (Chara vulgaris), wild celery (Vallisneria americana), and sago pondweed (Potamogeton pectinatus), removed during the fall migration period at Long Point, Lake Erie, Ontario. Exclosure experiments done in fall 1998 and 1999 showed that, as compared to ducks and abiotic factors, these two large herbivorous waterfowl did not have any additional impact on above or b...

2006-01-01

54

How to detect acidification in flowing bodies of water? Chemical and zoo-ecological indication along an acidification gradient in two brooks in the western Harz mountains  

International Nuclear Information System (INIS)

The population of the hyporheic interstice and moss cushions by meso- and macroinvertebrates as found at the three measuring points along the Alte Riefensbeek and the Grosse Soese, respectively, in the period from March 1987 to May 1988 is studied and evaluated together with chemical measurements performed between 1987 and 1990. The six measuring points are positioned along an acidification gradient ranging from non-acid to severely acidified. Chemical and biological paramerters are studied with regard to their suitability as indicators of acidification. A model is presented which decribes the influence of abiotic anthropogenic and natural factors on invertebrate species diversity and populations and which can serve as a basis for the calculation of critical deposition burdens. (orig.).

1991-09-24

55

Near-real time infrared observations of acidic sulfates in /open quotes/clean/close quotes/ air at Mauna Loa, Hawaii  

Energy Technology Data Exchange (ETDEWEB)

Sulfuric acid and its partially or completely neutralized salts with ammonia are believed to result from the oxidation of sulfur dioxide in cloud water and in other heterogeneous media present in the atmosphere. Due to the natural abundance of ammonia and the ubiquitous presence of sulfur in the atmosphere, (NH/sub 4/)/sub 2/SO/sub 4/ is commonly the dominant chemical species in the ambient aerosol. The amounts of ammonium sulfates are expected to be very low in areas far removed from anthropogenic emissions of sulfur dioxide. The chemical composition of submicrometer aerosol particles was determined at the Mauna Loa Observatory (MLO) on Mauna Loa in Hawaii during an eight-day period in August 1986. The MLO site was selected for this measurement because it is the only ground-based aerosol observatory in the remote Pacific Ocean that allows extended sampling of aerosols in the free troposphere. Measurements were made using an attenuated total internal reflection ...

1988-01-01

56

The comparative uptake and interaction of several radionuclides in the trophic levels surrounding the Los Alamos Meson Physics Facility (LAMPF) waste water ponds  

International Nuclear Information System (INIS)

A study was undertaken to examine the uptake, distribution, and interaction of five activation products (Co-57, Be-7, Cs-134, Rb-83, and Mn-54) within the biotic and abiotic components surrounding the waste treatment lagoons of the Los Alamos Meson Physics Facility (LAMPF). The study attempted to ascertain where, and what specific interactions were taking place among the isotopes and the biotic/abiotic components. A statistical approach, utilizing Multivariate Analysis of Variance (MANOVA), was conducted testing the radioisotopic concentrations by (1) the trophic levels (TROPLVL) in each position sampled on the grid, (2) where sampled on the grid (TRAN), (3) where sampled with-in each grid line (PLOT), and (4) the side with which sampled (SIDE). This provided both the dependent and independent variables that would be tested. The Null Hypothesis (Ho) tested the difference in the mean values of the isotopes within/between each of the four ...

1983-05-01

57

The comparative uptake and interaction of several radionuclides in the trophic levels surrounding the Los Alamos Meson Physics Facility (LAMPF) waste water ponds  

Energy Technology Data Exchange (ETDEWEB)

A study was undertaken to examine the uptake, distribution, and interaction of five activation products (Co-57, Be-7, Cs-134, Rb-83, and Mn-54) within the biotic and abiotic components surrounding the waste treatment lagoons of the Los Alamos Meson Physics Facility (LAMPF). The study attempted to ascertain where, and what specific interactions were taking place among the isotopes and the biotic/abiotic components. A statistical approach, utilizing Multivariate Analysis of Variance (MANOVA), was conducted testing the radioisotopic concentrations by (1) the trophic levels (TROPLVL) in each position sampled on the grid, (2) where sampled on the grid (TRAN), (3) where sampled with-in each grid line (PLOT), and (4) the side with which sampled (SIDE). This provided both the dependent and independent variables that would be tested. The Null Hypothesis (Ho) tested the difference in the mean values of the isotopes within/between each of the four ...

1989-08-01

58

Contaminant assimilation in newly created prairie wetlands  

Energy Technology Data Exchange (ETDEWEB)

Increased use of wetlands for habitat and water quality improvement emphasize the need for further study of abiotic-biotic interactions in these systems. This research examined contaminant assimilation within the water column of two newly created Colorado prairie wetlands (RMA3 and RMA4). To examine the influence of abiotic factors (e.g., alkalinity, suspended solids), ten chronic toxicity tests were performed from December 1991 through November 1993. In the first set of tests, Ceriodaphnia dubia were exposed to water from the two wetlands which was spiked with various concentrations of zinc. These tests suggested that water from RMA4 had higher contaminant assimilative capacity than water from RMA3. Preliminary analysis suggested suspended solids, pH, conductivity, and temperature were important factors affecting neonate production by C. dubia when exposed to zinc-spiked wetland water. To test the importance of suspended solids in contaminant ...

1994-12-31

59

Time-Resolved Aerosol Collector for CCSEM/EDX Single Particle Analysis  

Energy Technology Data Exchange (ETDEWEB)

An automated Time Resolved Aerosol Collector (TRAC) has been developed for sequential sampling of field-collected aerosols for laboratory-based Computer Controlled Scanning Electron Microscopy/Energy Dispersed X-ray (CCSEM/EDX) single particle analysis. The collector is optimized for use of grid-supported 20 nm carbon films as deposition substrates. The carbon films have low enough X-ray background to permit EDX analysis down to 0.1-0.2 ?m particles, including detection of low-Z elements: C, N, & O. The TRAC provides unattended sampling onto a set of 151 individual grids, at sequential time intervals as short as 1 min. After collection, the samples are sealed and refrigerated pending analysis. The utility of the TRAC-CCSEM/EDX approach is exemplified using the aerosol samples collected during the Texas 2000 Air Quality Studies (Aug. 15 ? Sept. 15, 2000). We are able to quantitatively follow the time evolution in the relative contribution of non-volatile particles such as ...

2003-01-02

60

Synthesis of alkylated deoxyno irimycin and 1,5-dideoxy-1,5-iminoxylitol analogues: : Polar side-chain modification, sulfonium and selenonium heteroatom variants, conformational analysis, and evaluation as glycosidase inhibitors  

DEFF Research Database (Denmark)

The syntheses of N-alkylated deoxynojirimycin and 1,5-dideoxy-1,5-iminoxylitol derivatives having either a D- or an L-erythritol-3-sulfate functionalized N-substituent are reported. The alkylating agent used was a cyclic sulfate derivative, whereby selective attack of the nitrogen atom at the least hindered primary center afforded the desired ammonium salt. In aqueous solution, these salts were configurationally labile at the ammonium center. Sulfonium and/or selenonium analogues of the ammonium salts were prepared by analogous reactions. The chalcogen salts were obtained as mixtures of diastereomers, separable in some cases, differing only in the stereochemistry at the configurationally stable sulfur or selenium atoms. Proof of configuration and conformation of each compound was obtained by detailed NMR experiments. The compounds are six-membered ring analogues of salacinol, a known sulfonium-salt glucosidase inhibitor. ...

2004-01-01

61

Proton spin lattice relaxation studies in lithium ammonium sulfate LiNH_4SO_4  

International Nuclear Information System (INIS)

Lithium ammonium sulfate (LAS) undergoes a phase transition at Tsub(c1) = 459.5deg K from a paraelectric phase (phase 1) to a ferroelectric phase (phase II) and again at Tsub(c2) = 283deg K to a polar ferroelastic phase (phase III). Proton spin lattice relaxation investigations in the temperature range 480-77deg K at 10 MHz show discontinuous changes in Tsub(1) at the transition temperatures, indicating first order phase transitions. The absence of the slow motion region (#omega#sub(not)tausub(not)>>1) shows that the ammonium ions are reorienting fast enough to keep the resonance absorption line narrow down to liquid nitrogen temperatures. The possibility of a second minimum and a low activation energy, Esub(a) = 2.659 kcal/mole, in phase III suggest the possibility of tunnelling of the protons at low temperatures. The nature of the transitions have been discussed in the light of the available literature. The unusually high activation ...

1978-12-31

62

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

63

Foam for combating mine fires  

Energy Technology Data Exchange (ETDEWEB)

The application of foam in dealing with underground fire is well known due to its smothering action by cutting off air feed to burning fuel as well as acting as coolant. Besides plugging air feed to fire, water could be virtually reached to the fire affected areas much beyond the jet range as underground galleries with low roof restrict jet range of water. This method also enables a closer approach of a fire fighting team by isolating the toxic gases and smoke with a foam plug. The paper describes the development of high expansion foam composition and its application technology in order that foam plug method can be suitably utilized for combating mine fires in India. Three compositions were recommended for generation of high expansion foam: (a) 0.5% sodium/ammonium lauryl sulphate, 0.15 to 0.2% sodium carboxy methyl cellulose, 0.1% booster; (b) 0.5% sodium/ammonium lauryl sulfate, 0.12 to 0.15% alkaline solution of gum arabic, 0.1 to 0.2% ...

1989-09-01

64

Sensitive characteristics of BAMO/NMMO/AN propellants; BAMO/NMMO/AN kei suishinyaku no kando tokusei  

Energy Technology Data Exchange (ETDEWEB)

Very important performances in the practical use of solid propellants are combustion and physical properties. Among the present solid propellants, composite propellants used ammonium perchlorate (AP) as oxidizers are adopted widely now due to these excellent performances. Recently, a combination of ammonium nitrates (AN) as oxidizers and azido polymers as binders in expected as the propellants which control decrease of combustion properties and satisfy unsensitivity. However, in order to use these azido polymers/AN propellants in practice, further, it is necessary to improve the specific impulse and the burning rate. In this report, aiming to improve the combustion properties of BAMO/NMMO/AN propellants, the sensitivity and the combustion properties of propellants added high energetic plasticizers in binders, further, displaced a part of AN to cyclotetramethylenetetranitramine (HMX) and double based base-grain (BG) are described. 8 refs., 3 ...

1998-01-01

65

Impedance spectroscopy study with H-doped ammonium uranylphosphate self supported membranes  

Energy Technology Data Exchange (ETDEWEB)

Equivalent circuit and electrical parameters for H-doped NH{sub 4}UO{sub 2}PO{sub 4}.3H{sub 2}O self supported membranes have been determined by impedance spectroscopy. The measurements were carried out with a dry membrane, at different temperatures, and a wet membrane in contact with different electrolyte solutions. Resistance values for the dry membrane decrease with temperature increase, which agrees with the weak protonic character of the H-doped ammonium uranylphosphate. On the other hand, differences in the electrical parameters, depending on the electrolyte considered were also obtained and are attributed to different conduction mechanisms. (Author).

1995-01-01

66

Effect of Coating of Ammonium Perchlorate with Fluorocarbon on Ballistic and Sensitivity Properties of AP/Al/HTPB Propellant  

British Library Electronic Table of Contents (United Kingdom)

Fluorocarbon polymers are used to enhance thermal stability and electrostatic protection of composite propellant compositions. A precipitation technique has been developed to coat ammonium perchlorate (AP) using a copolymer of hexafluoropropylene and vinylidene fluoride (HFP-VF) with the help of solvent-counter solvent method. The coated AP has been used to prepare propellant compositions in different ratio based on hydroxyl terminated polybutadiene (HTPB), aluminium powder along with uncoated AP and studied for viscosity build-up and visco-elastic behaviour as well as mechanical, ballistic, thermal and sensitivity properties keeping 86% solid loading. The data on viscosity build-up indicate that as the percentage of viton coated AP increases end of mix viscosity and viscosity build-up inc...

2009-01-01

67

Do spatial effects appear at low dilution rate in chemostat?  

British Library Electronic Table of Contents (United Kingdom)

The chemostat theory on two species competition has shown that the dilution rate where transition of dominance occurs - transition-dilution rate - is independent of limiting-nutrient concentration. However, we obtained the experimental data indicating that the transition-dilution rate changed with variations in limiting-ammonium concentrations, using the chemostat mixed-culture of the cyanobacterium Microcystis novacekii and the green alga Scenedesmus quadricauda. The transition-dilution rate was dependent on the concentration of limiting ammonium in the influx culture medium. We tried to simulate the experimental results. Though the dilution rate has been considered independent of nutrient concentration, we introduce the effective dilution rate that depends on nutrient concentration (ammo...

2009-01-01

68

Comparative resilience of soil and natural zeolite against adverse features of a municipal sewage. A preliminary investigation  

International Nuclear Information System (INIS)

A research was started aiming at evaluating the possible use of natural zeolites as exchange conditioners to improve and make durable the soil resilience against the adverse effects of the use of anomalous waters for irrigation purposes. This paper deals with a preliminary investigation on the comparative resilience of an Entisol with poor exchange properties and of a Neapolitan yellow tuff (NYT) sample against the adverse features of a dirty municipal sewage (DSW). Results showed that NYT treatment largely and significantly improved the poor soil exchange activity. In particular. NYT exchange sites selectively took up ammonium from DSW. As a consequence, ammonium was trapped, then protected against losses in the environment and, concurrently, exchangeable cations, such as K and Ca, were made free as plant nutrients. The results highlight the possible positive role of zeolitized tuff in restoring and sustaining soil resilience.

69

Chemical stability of {gamma}-butyrolactone-based electrolytes for aluminium electrolytic capacitors  

Energy Technology Data Exchange (ETDEWEB)

{gamma}-Butyrolactone-based electrolytes have been used as the operating electrolytes for aluminum electrolytic capacitors. The chemical stability of these electrolytes at elevated temperatures has been examined by monitoring the decrease in their electrolytic conductivities. The deteriorated electrolytes were analyzed by gas and liquid chromatography and the conductivity decrease was directly correlated with the loss of acid components. In quaternary ammonium hydrogen maleate/{gamma}-butyrolactone electrolytes, the maleate anion decomposed by decarboxylation resulting in a complex polymer containing polyester and polyacrylate structures. Quaternary ammonium benzoate/{gamma}-butyrolactone electrolytes decomposed by SN2 reactions giving alkyl benzoates and trialkylamines. The deterioration of the carboxylate salt/{gamma}-butyrolactone electrolytes was accelerated by electrolysis. (orig.)

1996-06-01

70

Ammonium azide: a commented example of an Ab initio structure (Re-) determination from X-ray powder diffraction  

Energy Technology Data Exchange (ETDEWEB)

The structure of ammonium azide (NH{sub 4})N{sub 3} was (re-)determined ab initio from x-ray powder diffraction experiment using synchrotron radiation. We tried to detail and comment the different steps involved in the structure determination. The compound crystallize in the orthorhombic Pmna space group (no.53) with a = 8.937(1) A, b= 3.8070(5) A, c = 8.664(1) A, V = 294.79(7) A{sup 3}; Z= 4. It was possible to locate and refine the hydrogen coordinates, in two different approaches, and to establish the H-bonds. The final structural parameters are in good agreement with previous results based on three-dimensional neutron diffraction. (Author)

2002-07-01

71

Ammonium azide: a commented example of an Ab initio structure (Re-) determination from X-ray powder diffraction  

International Nuclear Information System (INIS)

The structure of ammonium azide (NH_4)N_3 was (re-)determined ab initio from x-ray powder diffraction experiment using synchrotron radiation. We tried to detail and comment the different steps involved in the structure determination. The compound crystallize in the orthorhombic Pmna space group (no.53) with a = 8.937(1) A, b= 3.8070(5) A, c = 8.664(1) A, V = 294.79(7) A"3; Z= 4. It was possible to locate and refine the hydrogen coordinates, in two different approaches, and to establish the H-bonds. The final structural parameters are in good agreement with previous results based on three-dimensional neutron diffraction. (Author)

73

Use of magnetic treatment to intensify certain processes in the refining of chemical products of coking  

Energy Technology Data Exchange (ETDEWEB)

The results of the investigations show that magnetic treatment is a quite practical and effective method of intensifying certain technological processes in the coking industry. Magnetic treatment was utilized for improving the production of ammonium sulfate, refining of the naphthalene fraction, removal of sludge from wash oil in the benzol division, and the treatment of tar before fractionation. 2 references, 3 tables.

1983-01-01

74

The research on new production technique of yellow cake  

International Nuclear Information System (INIS)

As a new production technique of yellow cake, resorption with loaded resin-elution with acid ammonium nitrate-precipitation in two steps is studied. The results show that the produced yellow cake by the new production technique has better performance of settlement, filtration and dehydration. Each index of yellow cake accords with the first grade level issued by CNNC without washing, uranium and water content are 70% and 25%, respectively

2001-11-01

75

Pyrolysis of dichlorodithiourea cadmium(II)  

Energy Technology Data Exchange (ETDEWEB)

By means of infrared spectroscopy, x-ray diffraction, and differential thermal analysis, the authors investigate the pyrolysis of dichlorodithiourea cadmium, the vapor phase epitaxy of the cadmium sulfide film, and the composition of the solid and gaseous pyrolysis products. Those products are found to include the thiocyanates of guanidine, ammonium, and hydrogen along with cadmium oxides and sulfates and hydrochloric acid.

1987-02-20

76

Phosphorus-containing catalyst and catalytic cracking process utilizing the same  

Energy Technology Data Exchange (ETDEWEB)

A phosphorus-containing low alkali metal content zeolitic catalyst made from a clay starting material is provided. The catalyst is obtained by contacting a partially cation exchanged calcined zeolite-containing catalyst with an anion such as a dihydrogen phosphate anion or a dihydrogen phosphite anion and additionally with an ammonium salt other than a salt of an inorganic acid of phosphorus. A hydrocarbon catalytic cracking process utilizing the phosphorus-containing catalyst is also provided.

1985-03-12

77

Novel Method for Processing Respiratory Specimens for Detection of Mycobacteria by Using C18-Carboxypropylbetaine: Blinded Study  

UK PubMed Central (United Kingdom)

A novel method for processing respiratory specimens to improve culture and acid-fast staining of mycobacteria is introduced. This new method utilized N,N-dimethyl-N-(n-octadecyl)-N-(3-carboxypropyl)ammonium...Full Text Available

1998-07-01

78

Effects of electric field on the II-III phase transition in lithium ammonium sulphate and its deuterated analogue  

International Nuclear Information System (INIS)

Experimental results are presented on the quasi-statistic polarization reversal and on the effect of high dc electric field on the behaviour of LiNH_4SO_4 and LiND_4SO_4 monocrystals, namely in the vicinity of the II-III phase transformation.

1984-03-01

79

Catalysis over activated zeolites  

Science.gov (United States)

A process is provided for conducting organic compound conversion over a catalyst composition comprising a supported crystalline zeolite having a high initial silica-to-alumina mole ratio, said supported zeolite being prepared by compositing said crystalline zeolite with alumina, reacting the composite with a particular hydrogen fluoride solution in a specified way, drying the hydrogen fluoride reacted composite, treating the dried composite by hydrolysis, ammonolysis and/or by contact with an ammonium salt solution, and calcining the resulting material.

1985-02-19

80

Transcriptome analysis reveals salt-stress-regulated biological processes and key pathways in roots of cotton (Gossypium hirsutum L.).  

Science.gov (United States)

High salinity is one of the main factors limiting cotton growth and productivity. The genes that regulate salt stress in TM-1 upland cotton were monitored using microarray and real-time PCR (RT-PCR) with samples taken from roots. Microarray analysis showed that 1503 probe sets were up-regulated and 1490 probe sets were down-regulated in plants exposed for 3h to 100mM NaCl, and RT-PCR analysis validated 42 relevant/related genes. The distribution of enriched gene ontology terms showed such important processes as the response to water stress and pathways of hormone metabolism and signal transduction were induced by the NaCl treatment. Some key regulatory gene families involved in abiotic and biotic sources of stress such as WRKY, ERF, and JAZ were differentially expressed. Our transcriptome analysis might provide some useful insights into salt-mediated signal transduction pathways in cotton and offer a number of candidate genes as potential markers of tolerance to ...

2011-04-30

81

Expression profiles of precursor and mature microRNAs under dehydration and high salinity shock in Populus euphratica  

British Library Electronic Table of Contents (United Kingdom)

MicroRNAs (miRNAs) are small non-coding RNAs that play vital roles in plant abiotic stress responses via cleavage or translational inhibition of their target mRNAs. Populus euphratica is a typical stress-resistant sessile organism that grows in desert areas. Here, we identified sequences of 12 miRNA precursors from 11 families and 13 mature miRNAs from 12 families by PCR amplification in P. euphratica. To detect expression differences in mature miRNAs and their precursors under dehydration and high salinity shock in P. euphratica, we examined 14 miRNA precursors from 13 miRNA families and 17 mature miRNAs from 17 miRNA families using the SYBR Green RT?PCR assay. This is the first report of expression profiles for both precursor and mature miRNAs in P. euphratica. By profiling both the matu...

2011-01-01

82

Differences in p,p'-DDE bioaccumulation from compost and soil by the plants Cucurbita pepo and Cucurbita maxima and the earthworms Eisenia fetida and Lumbricus terrestris  

International Nuclear Information System (INIS)

Two plant species, Cucurbita pepo and Cucurbita maxima, and two earthworm species, Eisenia fetida and Lumbricus terrestris, were exposed to soil and compost with equivalent p,p'-DDE contamination. Pollutant bioconcentration was equal in plant roots in both media, but translocation was higher in C. pepo. Bioaccumulation by E. fetida was approximately 6- and 3-fold higher than that by L. terrestris in the soil and compost, respectively. For all species, p,p'-DDE uptake was significantly greater from soil than from compost; 7- to 8-fold higher for plant roots and 3- to 7-fold higher for worms. Abiotic desorption from soil was approximately twice that from the compost. When all the data are normalized for organic-carbon content of the media, the contaminant is more tightly bound by soil than compost. Although the risk associated with p,p'-DDE is higher in soil than compost, important mechanistic differences exist in contaminant binding to organic carbon in the two ...

2007-07-01

83

A habitat template approach to green building surfaces  

Energy Technology Data Exchange (ETDEWEB)

The use of entire plant communities of native species is gaining interest in the green roof industry. Plant communities must be matched with environmental conditions that mimic conditions in their original habitats. Urban built environments do not differ significantly from the rocky outcrops with poor, shallow soil that many plants colonize. This paper provided details of an experiment investigating the impact of plant community structure and species diversity on living roof performance. The aim of the experiment was to determine the impact of species diversity on precipitation interception, nutrient retention, temporal biomass constancy and roof temperature constancy. The diversity treatment included separate monocultures of 8 species in the community, randomly determined mixtures of 4 species, and a mixture of all 8. Functional groups included mosses, liverworts, colonial algae and a mycorrhizal inoculum. In a second experiment, between 1 and 4 of the functional groups were added to ...

2005-07-01

84

Multiple-shell planetary nebula formation  

Energy Technology Data Exchange (ETDEWEB)

Predictions of the combination of our recent model for the formation of planetary nebulae (due to a diverging pulsational instability) together with nuclear-burning shell flashing, with regard to formation of multiple shells, are explored and discussed.

1980-11-15

85

Thin TiO2 grown by metal?organic chemical vapor deposition on (NH4)2S x -treated InP  

British Library Electronic Table of Contents (United Kingdom)

The electrical characteristics of thin TiO2 films prepared by metal?organic chemical vapor deposition grown on a p-type InP substrate were studied. For a TiO2 film of 4.7?nm on InP without and with ammonium sulfide treatment, the leakage currents are 8.8?10?2 and 1.1?10?4?A/cm2 at +2 V bias and 1.6?10?1 and 8.3?10?4?A/cm2 at ?2?V bias. The lower leakage currents of TiO2 with ammonium sulfide treatment arise from the improvement of interface quality. The dielectric constant and effective oxide charge number density are 33 and 2.5?1013?cm2, respectively. The lowest mid-gap interface state density is around 7.6?1011?cm?2?eV?1. The equivalent oxide thickness is 0.52?nm. The breakdown electric field increases with decreasing thickness in the range of 2.5 to 7.6?nm and reaches 9.3?MV/cm at 2.5?n...

2011-01-01

86

Responses to ammonium and nitrate additions by boreal plants and their natural enemies  

Energy Technology Data Exchange (ETDEWEB)

Separate effects of ammonium (NH{sub 4} {sup +}) and nitrate (NO{sub 3} {sup -}) on boreal forest understorey vegetation were investigated in an experiment where 12.5 and 50.0 kg nitrogen (N) ha{sup -1} year{sup -1} was added to 2 m{sup 2} sized plots during 4 years. The dwarf-shrubs dominating the plant community, Vaccinium myrtillus and V. vitis-idaea, took up little of the added N independent of the chemical form, and their growth did not respond to the N treatments. The grass Deschampsia flexuosa increased from the N additions and most so in response to NO{sub 3} {sup -}. Bryophytes took up predominately NH{sub 4} {sup +} and there was a negative correlation between moss N concentration and abundance. Plant pathogenic fungi increased from the N additions, but showed no differences in response to the two N forms. Because the relative contribution of NH{sub 4} {sup +} and NO{sub 3} {sup -} to the total N deposition on a regional scale can vary substantially, the ...

2006-05-15

87

Oxide growth on aluminium alloys in the presence of ammonium fluoborate  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study as to determine the mechanisms involved in using ammonium fluoborate as a reducing atmosphere when preheating a high magnesium content aluminium alloy. Rutherford Backscattering (RBS) has been the major technique used in the analysis of samples, it revealed significant reduction in both the diffusion of magnesium to the surface and the calculated oxide thickness in the presence of NH{sub 4}BF{sub 4}. At temperatures above 500 deg C in air, SEM images revealed depressions and voids due to incipient melting at various stages, around the grain boundaries. Grain boundaries effectively acted as pipes aiding the diffusion of magnesium to the surface. These results have been verified through compositional analysis with both RBS and auger electron spectroscopy (AES). Results from NH{sub 4}BF{sub 4} atmosphere preheat conditions showed significant improvements. It was verified experimentally that above 500 deg C , AA5182 alloys undergo incipient ...

1996-12-31

88

Inhibition of corrosion resistant alloys in hot hydrochloric acid solutions  

Energy Technology Data Exchange (ETDEWEB)

Weight loss measurements were performed in 20% and 28% hydrochloric acid at 90/sup 0/C on carbon steel, 22Cr5Ni duplex stainless steel, and two superaustenitic steels - 27Cr31Ni3Mo and 19Cr25Ni4Mo -, in presence of organic substances used singly or mixed. The organic substances examined were quaternary ammonium salts (1-4-pyridyl)-pyridinium chloride hydrochloride, dodecylpyridiniumchloride, benzyldimethylstearylammonium chloride, and dodecyltrimethylammonium bromide), alkynols (1-octyn-3-ol, propargyl alcohol) and trans-cinnamaldehyde. The synergistic effect of potassium iodide on the inhibitive efficiency of the organic substances was studied. The variations of corrosion rate during the test time (normally six hours) were recorded by means of polarization resistance measurements. Polarization curves were also recorded. The results showed that the corrosion rates of the four steels examined can be reduced to less than 1 mg/cm/sup -2/ . h/sup -1/ using ternary ...

1988-12-01

89

Economic evaluation of an electrolytic process to recover lead from scrap batteries. Information circular/1986  

Energy Technology Data Exchange (ETDEWEB)

The publication is an economic evaluation of the Bureau of Mines electrolytic process for recovering lead from scrap lead-acid batteries. In this process, scrap batteries are crushed and separated into metal and sludge fractions. The metal fraction is cast as anodes and electro-refined. Lead in the sludge fraction is converted to lead carbonate by reaction with an ammonium carbonate-ammonium bisulfite solution. The lead carbonate is then dissolved in a fluosilicic acid electrolyte from which pure lead metal is electrowon. A cost estimate is presented for a plant capable of processing 10,000 scrap batteries per day. The fixed capital cost for the plant is estimated to be $14 million on a fourth quarter 1984 basis. Operating costs are estimated to be $0.15/lb Pb recovered. Assuming a lead selling price of $0.17/lb, the interest rate of return on investment after taxes is 11 pct. A lead selling price of about $0.21/lb is needed to obtain a ...

1986-01-01

93

Acidizing subterranean well formations containing deposits of metal compounds  

Science.gov (United States)

Methods of acidizing a subterranean well formation, acidizing compositions, and sequestering additives for preventing the precipitation of metal compounds in the formation are described. Use of the methods and chemicals described should lead to improved formation permeability as compared to use of previous methods and chemicals. 12 claims.

1979-04-24

94

Tracing of salicylic acid additive during precipitation of zirconium  

International Nuclear Information System (INIS)

This paper presents the results of experimental study carried out to know whether the salicylic acid used as an additive during the precipitation of zirconium using ammonium hydroxide solution goes into the filtrate, remains in the hydrated zirconia or gets distributed between the both under the ambient conditions of precipitation. Keeping its simplicity and amenability to adopt on a routine basis, spectrophotometric method has been chosen for the purpose among the many methods available and the problems associated in determining salicylic acid in the presence of zirconium and the medial measures to circumvent the same have been brought out in detail. (author)

2011-02-22

95

State of molybdenum ions in ultrastable Y zeolite  

Energy Technology Data Exchange (ETDEWEB)

The methods of diffuse-reflection optical spectroscopy and EPR were used to study the state of molybdenum in catalysts prepared by impregnating ultrastable zeolite with molybdenum salt solutions and by mixing in the solid phase with MoCl/sub 5/. It has been shown that molybdenum introduced into zeolites in small amounts is found basically in the form of isolated hexavalent ions of molybdenum. In addition, Mo/sup 5 +/ and Mo/sup 4 +/ ions are also present. Heteropolycompounds also form. The molybdenum ions are most readily reduced in the zeolite prepared by impregnation with a solution of ammonium paramolybdate.

1987-10-01

96

Review of experience gained in fabricating nuclear grade uranium and thorium compounds and their analytical quality control at the Instituto de Energia Atomica, Sao Paulo, Brazil  

International Nuclear Information System (INIS)

The main activities developed at 'Instituto de Energia Atomica' Sao Paulo, Brazil, on the recovery of uranium from ores, the purification of uranium and thorium raw concentrates and their transformation in nuclear grade compounds, are reviewed. The design and assemble of pilot facilities for ammonium diuranate (ADV) uranium tetrafluoride, uranium trioxide, uranium oxide microspheres, uranyl nitrate denitration, uranim hexafluoride and thorium compounds are discussed. The establishment of analytical procedures are emphasized.

1980-08-22

97

Process for the chemical removal of ash from coal and device for carrying out this process. Verfahren zur chemischen Entfernung der Asche aus Kohle sowie Vorrichtungen zur Durchfuehrung dieses Verfahrens  

Energy Technology Data Exchange (ETDEWEB)

In order to remove ash from coal, it is introduced into an aqueous ash removal solution, which contains nitric acid or citric acid and ammonium hydrogen fluoride. The coal without ash is then separated from the aqueous solution. According to the process, either finely ground coal is introduced into the ash removel solution or the coal with the solution is ground in a wet pulveriser.

1981-03-13

98

Primary explosives  

Energy Technology Data Exchange (ETDEWEB)

The present invention provides a compound of the formula (Cat).sup.+.sub.z[M.sup.++(5-nitro-1H-tetrazolato-N2).sup.-.sub.x(H.sub.2- O).sub.y] where x is 3 or 4, y is 2 or 3, x+y is 6, z is 1 or 2, and M.sup.++ is selected from the group consisting of iron, cobalt, nickel, copper, zinc, chromium, and manganese, and (Cat).sup.+ is selected from the group consisting of ammonium, sodium, potassium, rubidium and cesium. A method of preparing the compound of that formula is also disclosed.

2009-03-03

99

Primary explosives  

Energy Technology Data Exchange (ETDEWEB)

The present invention provides a compound of the formula (Cat).sup.+.sub.z[M.sup.++(5-nitro-1H-tetrazolato-N2).sup.-.sub.x(H.sub.2- O).sub.y] where x is 3 or 4, y is 2 or 3, x+y is 6, z is 1 or 2, and M.sup.++ is selected from the group consisting of iron, cobalt, nickel, copper, zinc, chromium, and manganese, and (Cat).sup.+ is selected from the group consisting of ammonium, sodium, potassium, rubidium and cesium. A method of preparing the compound of that formula is also disclosed.

2011-01-25

100

Interaction between flavonoid, quercetin and surfactant aggregates with different charges  

British Library Electronic Table of Contents (United Kingdom)

The interactions of flavonoid, quercetin with sodium dodecyl sulfate (anionic surfactant) and cetyltrimethyl ammonium bromide (cationic surfactant) micelles were investigated. The average location site of quercetin in different micelles was determined by the cyclic voltammetry method with the aid of molecular optimization. The interaction parameters of quercetin with micelles of different charges such as binding constant K and normal binding energy DG were calculated. Furthermore, the morphologic change of the SDS and CTAB spherical micelles and rod-like micelles upon their interaction with quercetin was also observed.

2006-01-01

101

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

102

Electron beam curable phenol-formaldehyde resin  

International Nuclear Information System (INIS)

The novolac type phenolic resins were synthesized and electron beam curing was carried out to the prepolymer obtained by the reaction of the phenolic resin and glycidyl meth acrylate in the presence of triethylbenzyl ammonium chloride. When the prepolymer and its mixtures with monomers were irradiated using electron beams at a dose rate of 3 Mrad/sec, the curing were completed at a dose 2.5 and 3 Mrad respectively. The effects of oxygen and that of hydroxyl group in the prepolymer on electron beam curing were also examined. (author).

103

Coordination compounds of oxovanadium(4), nickel(2) and copper(2) with bis-(salicyliden)-thiocarbazide  

International Nuclear Information System (INIS)

A reaction of aqueous-methanol solutions of thiocarbazide and salycilic aldehyde, taken in a molal ratio of 1:2 on the matrix of oxovanadium(VO) in the presence of aqueous ammonium results in a coordination compound of the VC_1_5H_1_2N_4O_3S composition. Similar compounds are obtained with salts of nickel(2) and copper(2). Complexes of oxovanadium(4) and copper(2) have effective magnetic moments normal for systems with a spin of 1/2. The compound with nickel is diamagnetic. These data agree with the configuration of the coordination compounds obtained.

104

Combustion flames of high energy substance  

Energy Technology Data Exchange (ETDEWEB)

The currently available propellants achieve about 95% of the combustion performance which can be expected theoretically at this time, consequently a technological breakthrough concerning new propellants have been demanded. Among high energy substances which are being studied, polymer azide which can continue combustion without relying on the oxidation reaction is a typical high energy substance to be used for a propellant of the next generation. The composite propellant which has polymer azide as fuel component and ammonium nitrate as oxidizer is considered to be the extremely promising propellant, since it provides no combution product which causes the environmental destruction. (6 figs, 4 refs)

1988-04-30

105

Amberlyst A-15: Reusable catalyst for the synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted-1H-imidazoles under MW irradiation  

British Library Electronic Table of Contents (United Kingdom)

One-pot multi-component condensation of benzyl, aldehydes, ammonium acetate and primary amines were used for synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted-1H-imidazole derivatives under MW radiation using amberlyst A-15 as a catalysts. This catalyst has several advantages (simple work-up, low cost and reusability).

2011-01-01

106

Rates of galactic star formation  

Energy Technology Data Exchange (ETDEWEB)

A remarkably simple argument successfully accounts for the rate of star formation in different galaxies. The snag is that the timescale is uncomfortably short.

1985-08-29

107

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

108

Transfer of 137Cs and 60Co in a waste retention pond with emphasis on aquatic insects  

International Nuclear Information System (INIS)

The objectives of this research were (1) to analyze the transfers of 137Cs and 60Co in a retention pond, with emphasis on aquatic insects and (2) to determine if detectable concentrations of these radionuclides are exported by emerging aquatic insects. We analyzed the radionuclide concentrations in the following components: water solution, bottom sediments, suspended particulate matter, plankton, floating mats of filamentous algae, benthic macroinvertebrates, and emerging aquatic insects. Samples were collected quarterly from June 1981 to April 1982. The lowest concentrations (in picocuries per milliliter) occurred in solution (range: 1.4 X 10(2) to 3.2 X 10(2) for 137Cs and 8.1 X 10(-1) to 2.2 X 10(0) for 60Co). The highest concentrations (in picocuries per gram dry weight) occurred in the sediments (range: 1.5 X 10(4) to 1.1 X 10(8) for 137Cs and 1.0 X 10(2) to 4.3 X 10(6) for 60Co). The primary producers and aquatic insect consumers had concentrations of both radionuclides that were ...

109

The Effects of Surface Chemistry on the Properties of Proteins Confined in Nano-porous Materials  

Energy Technology Data Exchange (ETDEWEB)

The entrapment of proteins using the sol-gel route provides a means to retain its native properties and artificially reproduce the molecular crowding and confinement experienced by proteins in the cell allowing investigation of the physico-chemical and structural properties of biomolecules at the biotic/abiotic interface. The biomolecules are spatially separated and 'caged' in the gel structure but solutes can freely permeate the matrix. Thus, properties such as the folding of ensembles of individual molecules can be examined in the absence of aggregation effects that can occur in solution studies. Green fluorescent protein from Aequorea coerulescens was used as a model protein to examine the unfolding/re-folding properties of protein in silica gels. The recombinant protein was isolated and purified from Escherichia coli extracts by cell lysis, three-phase partitioning, dialysis, and anion exchange chromatography. The purity of the protein was ...

2007-09-01

110

Kootenai River Floodplain Ecosystem Operational Loss Assessment, Protection, Mitigation and Rehabilitation, 2007-2008 Annual Report.  

Science.gov (United States)

The overarching goals of the 'Kootenai River Floodplain Ecosystem Operational Loss Assessment, Protection, Mitigation and Rehabilitation' Project (BPA Project No.2002-011-00) are to: (1) assess abiotic and biotic factors (i.e., geomorphologic, hydrological, aquatic and riparian/floodplain communities) in determining a definitive composition of ecological integrity, (2) develop strategies to assess and mitigate losses of ecosystem functions, and (3) produce a regional operational loss assessment framework. To produce a scientifically defensible, repeatable, and complete assessment tool, KTOI assembled a team of top scientists in the fields of hydrology, hydraulics, ornithology, entomology, statistics, and river ecology, among other expertise. This advisory team is known as the Research Design and Review Team (RDRT). The RDRT scientists drive the review, selection, and adaptive management of the research designs to evaluate the ecologic functions ...

2009-02-18

111

Heats (enthalpies) of formation of coals and the thermodynamic evaluation of the coal formation process  

British Library Electronic Table of Contents (United Kingdom)

An approach to the calculation of the quantity of heat consumed in the process of coal formation is presented. The variability of this parameter in a coalification series is analyzed using coals from the Kuznetsk and Tunguska Basins as an example.

2011-01-01

112

Formation and evolution of the protoplanetary disk  

International Nuclear Information System (INIS)

A disk formation model during collapse of the protosolar nebula, yielding a low-mass protoplanetary disk is presented. The following subject areas are covered: (1) circumstellar disks; (2) conditions for the formation of stars with disks; (3) early evolution of the protoplanetary disk; and (4) temperature conditions and the convection in the protoplanetary disk.

1989-01-02

113

Formate Dehydrogenase of Clostridium thermoaceticum: Incorporation of Selenium-75, and the Effects of Selenite, Molybdate, and Tungstate on the Enzyme  

UK PubMed Central (United Kingdom)

The formation of the nicotinamide adenine dinucleotide phosphate-dependent formate dehydrogenase in Clostridium thermoaceticum is stimulated by the presence of molybdate and selenite...Full Text Available

1973-11-01

114

Wastewater treatment; Abwasserreinigung  

Energy Technology Data Exchange (ETDEWEB)

The methods introduced for the field of cleaning waste water can be classified under various processes. Chemical oxidation is done with ozone, hydrogen peroxide and ultraviolet irradiation with subsequent biological decomposition. Another method is ultra-filtration with recovery of valuable materials or waste water ponds with algae biomass to decompose ammonium compounds, nitrates and phosphates. (EF) [Deutsch] Die auf dem Gebiet der Abwasserreinigung vorgestellten Methoden kann man in verschiedene Verfahren einordnen. Die chemische Oxidation erfolgt mit Ozon, Wasserstoff-Peroxid, UV Bestrahlung und anschliessenden biologischen Abbau. Eine andere Methode ist die Ultrafiltration mit Rueckgewinnung von Wertstoffen oder Abwasserteiche mit Algenbiomasse zum Abbau von Ammoniumverbindungen, Nitraten und Phosphaten. (EF)

1994-11-01

115

Synthesis and investigation of tungsten-phosphorus catalysts  

Energy Technology Data Exchange (ETDEWEB)

The authors present the results of their investigation of the effect of phosphorus compounds on the activity of tungsten-containing catalysts in the oxidation of ethane. They investigated tungsten-phosphorus catalysts with different phosphorus concentrations (calculated on the basis of P/sub 2/O/sub 5/). The catalysts were prepared by heat decomposition of the starting compounds at 750/sup 0/C for 4 h. As their starting compounds, they used two types of materials: heteropoly acids mixtures of monosubstituted ammonium phosphoric and tungstic acids. The specific surface area of the catalysts was determined using the nitrogen desorption method. The x-ray phase analysis was carried out using a DRON-1.5 diffractometer. The catalytic activity was determined using the impulse method in a reactor with a vibrofluidized catalyst layer.

1988-11-10

116

Preparation and evaluation of a novel glass-ionomer cement with antibacterial functions  

British Library Electronic Table of Contents (United Kingdom)

Objective.The objective of this study was to use the newly synthesized poly(quaternary ammonium salt) (PQAS)-containing polyacid to formulate the light-curable glass-ionomer cements and study the effect of the PQAS on the compressive strength and antibacterial activity of the formed cements.Materials and methods.The functional QAS and their constructed PQAS were synthesized, characterized and formulated into the experimental high-strength cements. Compressive strength (CS) and Streptococcus mutans viability were used to evaluate the mechanical strength and antibacterial activity of the cements. Fuji II LC cement was used as control. The specimens were conditioned in distilled water at 37 degrees C for 24 h prior to testing. The effects of the substitute chain length, loading as well as gra...

2011-01-01

117

Morphology, structure, and conductivity of polypyrrole prepared in the presence of mixed surfactants in aqueous solutions  

British Library Electronic Table of Contents (United Kingdom)

Polypyrrole (PPy) was prepared from different mixed-surfactant solutions with ammonium persulfate as an oxidant. Three types of combinations were selected, including cationic/anionic, cationic/nonionic, and anionic/nonionic mixed-surfactant solutions. The surfactants used in the experiments included cetyltrimethylammonium bromide (cationic surfactant), sodium dodecyl sulfate (anionic surfactant), sodium dodecyl sulfonic acid salt (anionic surfactant), poly(vinyl pyrrolidone) (nonionic surfactant), and poly(ethylene glycol) (nonionic surfactant). The morphology, structure, and conductivity of the resulting PPy were investigated in detail with scanning electron microscopy, Fourier transform infrared spectra, and the typical four-probe method, respectively. The results showed that the interac...

2007-01-01

118

Minimizing sulfur contamination and rinse water volume required following a sulfuric acid/hydrogen peroxide clean by performing a chemically basic rinse  

Energy Technology Data Exchange (ETDEWEB)

Sulfuric acid hydrogen peroxide mixtures (SPM) are commonly used in the semiconductor industry to remove organic contaminants from wafer surfaces. This viscous solution is very difficult to rinse off wafer surfaces. Various rinsing conditions were tested and the resulting residual contamination on the wafer surface was measured. The addition of small amounts of a chemical base such as ammonium hydroxide to the rinse water has been found to be effective in reducing the surface concentration of sulfur and also mitigates the particle growth that occurs on SPM cleaned wafers. The volume of room temperature water required to rinse these wafers is also significantly reduced.

1997-08-01

119

Growth and defects of explosives crystals  

Energy Technology Data Exchange (ETDEWEB)

Large single crystals of PETN, RDX, and TNT can be grown easily from evaporating ethyl acetate solutions. The crystals all share a similar type of defect that may not be commonly recognized. The defect generates conical faces ideally mosaic crystals, and may account for the polymorphs'' of TNT and detonator grades of PETN. TATB crystals manufactured by the amination of trichlorotrinitrobenzene in dry toluene entrain two forms of ammonium chloride. One of these forms causes worm holes'' in the TATB crystals that may be the reason for its unusually low failure diameters. Strained HMX crystals form mechanical twins that can spontaneously revert back to the untwinned form when the straining force is removed. Large strains or temperatures above 100[degrees]C lock in the mechanical twins.

1992-01-01

120

Growth and defects of explosives crystals  

Energy Technology Data Exchange (ETDEWEB)

Large single crystals of PETN, RDX, and TNT can be grown easily from evaporating ethyl acetate solutions. The crystals all share a similar type of defect that may not be commonly recognized. The defect generates conical faces ideally mosaic crystals, and may account for the ``polymorphs`` of TNT and detonator grades of PETN. TATB crystals manufactured by the amination of trichlorotrinitrobenzene in dry toluene entrain two forms of ammonium chloride. One of these forms causes ``worm holes`` in the TATB crystals that may be the reason for its unusually low failure diameters. Strained HMX crystals form mechanical twins that can spontaneously revert back to the untwinned form when the straining force is removed. Large strains or temperatures above 100{degrees}C lock in the mechanical twins.

1992-12-01

121

Desulphurisation of fumes as a potential source of prime materials  

Energy Technology Data Exchange (ETDEWEB)

A survey is given by the authors of methods of removing the sulphur dioxide content of fumes which can be linked together with producing useful final products. From these technologies those suppling well utilizable gypsum, the Walther process, producing ammonium sulphate, the Wellman-Lord and Bergbau-Forschung processes, respectively adapted to produce sulphuric acid or sulphur, may be of interest. Also in the method of fumes desulphurisation by catalysis by manganese, developed in KBFI, utilizable final products are given. Background of the work of developing this method. Detailed description of the manganese catalytic method based on the use of a red mud desulphurizing agent. By this process, in addition to desulphurizing fumes, enriched red mud with reduced Na/sub 2/O content is produced, which as an iron carrier, is to be reckoned with, or to be used in the cement industry for replacing imported calcined pyrites.

1986-01-01

122

Comparison of levels of trace elements extracted from fly ash and levels found in effluent waters from a coal-fired power plant  

Science.gov (United States)

Trace elements were extracted from a coal-fired power plant electrostatic precipitator ash with nitric acid, hydrochloric acid, citric acid, redistilled water, and ammonium hydroxide as extractants. Effluent waters at this plant were sampled to assess the elevation of trace element concentrations compared with intake waters. The results showed a positive correlation between those elements most extractable by water (B, F, Mo, and Se) or acid (As, B, Cd, F, Mo, and Se) and those elements most elevated in effluent waters (As, B, F, Mo, and Se).

1977-10-01

123

Chemically produced nanostructured ODS-lanthanum oxide-tungsten composites sintered by spark plasma  

British Library Electronic Table of Contents (United Kingdom)

High purity W and W-0.9La2O3 (wt.%) nanopowders were produced by a wet chemical route. The precursor was prepared by the reaction of ammonium paratungstate (APT) with lanthanum salt in aqueous solutions. High resolution electron microscopy investigations revealed that the tungstate particles were coated with oxide precipitates. The precursor powder was reduced to tungsten metal with dispersed lanthanum oxide. Powders were consolidated by spark plasma sintering (SPS) at 1300 and 1400degreeC to suppress grain growth during sintering. The final grain size relates to the SPS conditions, i.e. temperature and heating rate, regardless of the starting powder particle size. Scanning electron microscopy revealed that oxide phases were mainly accumulated at grain boundaries while the tungsten matrix ...

2011-01-01

124

Anaerobic treatment of biodiesel by-products in a pilot scale reactor  

British Library Electronic Table of Contents (United Kingdom)

In this work, long-term operation of a pilot scale mixed anaerobic reactor processing crude glycerol and rapeseed meal is discussed. These materials are generated as by-products of biodiesel production. Mixed reactor was operated under mesophilic conditions for the period of 654 days. Total cumulative production of biogas reached 379 m3 (at atmospheric pressure and ambient temperature). Maximum volumetric loading achieved during the operation was 2.17 kg m?3 d?1 for the crude glycerol dose of 2 L. When dosing crude glycerol as a single substrate, average specific production of biogas of 0.76 m3 per L of the g-phase was achieved. The lack of nutrients in the g-phase had to be compensated by an addition of ammonium nitrogen in the form of urea into the reactor. Long term processing of crude ...

2011-01-01

125

Alkylaldehyde-bisulfite adducts as cleavable surfactants  

British Library Electronic Table of Contents (United Kingdom)

Alkylaldehyde-bisulfite adducts with octyl, decyl, and dodecyl groups (CnS: n=8,10,12) were synthesized and the surface-active properties of the water-soluble compounds were compared. Exchange of the counter anions of C10S and C12S from sodium to tetramethylammonium solubilized them in water. The latter ammonium salt (C12S-QA) had surface activities as good as a classical surfactant, sodium dodecylsulfate, and dissociated promptly in weakly basic solution at room temperature to be a non-surfactant. It was also found that C12S-QA solubilized a hydrophobic substrate (solid), N,N-dimethyl-3-nitroaniline, in water and then separated it as a precipitate after alkali treatment.

2007-01-01

126

Active hydrogen by chemical ionization mass spectrometry.  

Science.gov (United States)

A means of determination of a ctive hydrogen of hydroxyl, carboxyl, sulfhydryl, amino, amido and sulfonamido groups by chemical ionization mass spectrometry using ammonia and trideuterioammonia as reagent gases is described. The method is based on exchange of active hydrogen for deuterium occurring during the chemical ionization process using trideuterioammonia, with comparison of m/z for ammonium adduct [M + NH1]+ and trideuterioammonium adduct [M--nH + nD + ND4]+, or of protonated molecular ion [M + H]+ and deuteronated molecular ion [M--nH + nD + D]+ yielding the number of active hydrogens. Applications have been made to several classes of biologically important compounds. PMID:427257

1979-01-01

127

A novel process for extraction of natural sweetener from licorice (Glycyrrhiza glabra) roots  

British Library Electronic Table of Contents (United Kingdom)

Pressurized hot water extraction (PHWE) is a very useful technique for recovering bioactive molecules from natural materials using subcritical compressed liquid water in the temperature range of 50-150degreeC. A novel process has been developed for making a natural sweetener from licorice (Glycyrrhiza glabra) roots involving selective chemical reaction and easy separation, for recovering mono-ammonium glycyrrhizate (MAG) using hot water with dissolved ammonia and pressurized with carbon dioxide. The performance of the novel PHWE process has been evaluated to ascertain the optimum process parameters to maximize the recovery of MAG by varying the parameters, such as temperature (30-120degreeC), pressure (1-10atm), extraction time (60-120min), water-to-feed ratio (20-40ml/g), number of stages...

2008-01-01

128

A novel method of single step hydrophobic interaction chromatography for the purification of phycocyanin from Phormidium fragile and its characterization for antioxidant property  

British Library Electronic Table of Contents (United Kingdom)

Phycocyanin - a major phycobiliprotein constitutively produced by many cyanobacteria hold several promising applications in diagnostics, biomedical research, and therapeutics. This paper discusses a novel rapid method for the purification of cyanobacterial phycocyanin (C-PC) from Phormidium fragile using hydrophobic interaction chromatography. The protein was extracted and concentrated by grinding under liquid nitrogen and ammonium sulfate fractionation. C-PC was purified by single step hydrophobic interaction chromatography. Purified phycocyanin showed absorbance maximum (lmax) at 624nm. The criterion of purity (R) achieved was 4.52. Phycocyanin to phycoerythrin and phycocyanin to allophycocyanin purity ratio were 3.85 and 7.49, respectively. The purified protein showed a pI of 5.2 and ha...

2008-01-01

129

Nascent Aneurysm Formation at the Basilar Terminus Induced by Hemodynamics  

UK PubMed Central (United Kingdom)

Background and PurposeHemodynamic insults at arterial bifurcations are hypothesized to play a key role in intracranial aneurysm formation. This study investigates...Full Text Available

2008-07-01

130

International Patenting Trends in Advanced Materials: Ceramics  

Science.gov (United States)

International Patenting Trends in Advanced Materials: Ceramics (June 18, 1999) This report is the ... manufacturing, biotechnology, and advanced materials. Hypertext Format Portable Document Format ...

131

Fate of gypsum-sulphur applied to soybean on Typic haplustepts  

International Nuclear Information System (INIS)

Field experiments were conducted on the sulphur-deficient Typic Haplustepts of the IARI farm for two consecutive, kharif seasons viz. 1996 and 1997 with soybean cultivar Pusa 22 as the crop. Varying rates of S as gypsum were basally applied in the main plots adjacent to the micro plots (1 m x 1 m) to quantify the partitioning of the fertilizer-sulphur taken up by soybean and its distribution in the soil profile. Soybean responded to the application of sulphur, with increase in yield being obtained up to rate of 40 kg S ha"-"1. Data computed on distribution of the S derived from labelled gypsum and percent S utilization by the soybean crop increased from 13.23 and 4.15 to 23.41 and 6.39, respectively. During 1996, the per cent utilization of labelled S ranged from 5.6 to 8.8. Monitoring of added sulphur in the soil profile up to a depth of 1 m revealed maximum accumulation of the added S in 30-60 cm soil layer. With the help of "3"5S around 11 to 18 per cent of the added S was traced in ...

2004-06-01

132

Bioavailability of nitrogen from sewage sludge using "1"5N-labelled ammonium sulphate  

International Nuclear Information System (INIS)

The high nutrient nitrogen and organic matter contents of sewage sludge (SS) make it a potential organic fertilizer for sandy soil. In this study, "1"5N-labelled ammonium sulphate was used to investigate the availability of nitrogen from irradiated and non-irradiated sewage sludge to tomato plants. The application of sewage sludge to sandy soil increased dry matter production (DMP), nitrogen yield (NY) and nitrogen recovery (NR) over two successive years. A positive relationship was found between sludge application rate and DMP and NY. The increase was significantly higher (P=0.05) in irradiated than non-irradiated sewage sludge. Total nitrogen derived from non-irradiated sewage sludge are : 48.0, 63.7, 73.5, 105.2 Kg/ha, whereas, the total nitrogen derived from irradiated sewage sludge are: 55.1, 72.5, 88.9, 141.4 Kg/ha corresponding to application rates of 10 t/ha, 20 t/ha, 30 t/ha, respectively. This was attributed to higher dry matter production in the later ...

2001-01-01

136

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

137

Luminescence dating of Beach-Rock formations  

International Nuclear Information System (INIS)

... excessive. Due to the response being too weak, attempts to use Infrared

2000-05-15

140

Formation of interphase layers in titanium alloys under repeated loading  

International Nuclear Information System (INIS)

Cyclic strength of #alpha#+#beta#-titanium alloy BT3-1 is studied under load frequencies of 33 and 300 Hz. The increase in the cyclic strength with growing frequency is caused by formation of FCC interphase layers of titanium hydrides. Their formation is one of possible ways of raising the fatigue strength of titanium alloys. Peculiarities of FCC interlayer formation in #alpha#+#beta# phases under loading frequency variation are revealed.

142
143

Formation and Evolution of Bulges  

CERN Document Server

After presenting three ways of defining a bulge component in disc galaxies, we introduce the various types of bulges, namely the classical bulges, the boxy/peanut bulges and the disc-like bulges. We then discuss three specific topics linked to bulge formation and evolution, namely the coupled time evolution of the bar, buckling and peanut strengths; the effect of velocity anisotropy on peanut formation; and bulge formation via bar destruction.

2007-01-01

146

Chloropicrin formation during oxidative treatments in the preparation of drinking water  

Energy Technology Data Exchange (ETDEWEB)

Chlorination of water can lead to the formation of chloropicrin. The numerous potential precursors (of various reactivities) observed during this study, confirm this hypothesis. Combination of ozonation and chlorination can also lead to the formation of this compound, dangerous to health; however, the conditions of the formation and particularly the impact of a nitration reaction in the gas phase are still not clearly defined.

1985-12-01

148

APOD: 2004 September 4 - Neutron Mars  

Science.gov (United States)

ice could be responsible for the formation of martian gullies. Tomorrow's picture: whirlpool ...

2011-10-07

150

Stratigraphy and sedimentary environment of the Coalspur Formation  

Energy Technology Data Exchange (ETDEWEB)

The Coalspur Formation is a continental succession of interbedded mudstone, siltstone and fine grained sandstone with subordinate coarser grained sandstone layers and channel lag deposits. Chert-pebble conglomerate (the Entrance conglomerate) occurs at the base of the formation, and coal beds interbedded with coaly shale and numerous thin bentonites occur in the upper part of the formation. An economically significant amount of high-quality thermal coal occurs within the upper, Paleocene part of the formation named the Coalspur coal zone. Coal from this zone, also known as the Coal Valley coal zone is being exploited in the Coal Valley Mine. 17 refs., 4 figs.

1990-01-01

151

Calibration and analysis of soil carbon efflux estimates with closed chambers at Forsmark and Laxemar  

International Nuclear Information System (INIS)

The Forsmark and the Laxemar investigation areas are examined by the Swedish Nuclear Fuel and Waste Management Co. for a possible construction of a deep repository for nuclear waste. In the case of a future leakage of waste, the radioactive isotopes could end up in the ecosystems above the repository. The fate of the radionuclides and their possible radiological impacts are then highly determined by ecosystem carbon cycling. An important part of the carbon cycling is the soil carbon effluxes, and in the investigation areas soil carbon effluxes have been examined with the closed chamber technique. This paper is divided into two parts. Firstly, there were problems with the equipment measuring the soil carbon dioxide efflux, and the first part is a description of the problem, how it was corrected and its possible causes. The second part is a manual in how to analyse data and calculate annual estimates of soil carbon efflux. The field measurement by the EGM-4 is just an occasional estimate ...

2007-01-01

152

Complexing of vanadium(3) with chromotropic acid derivatives  

International Nuclear Information System (INIS)

A spectrophotometric study has been made of the complex formation of vanadium (3) with arsenazo(1), arsenazo(3) and some monosubstituted derivatives of chromotropic acid and sulphanylamides. In acid medium vanadium (3) reacts with each of these reagents to produce a 1:1 complex. Optimum conditions of the complex formation was found. The effect of H"+ on the complex formation of vanadium (3) with chromotropic acid derivatives was established. It was found by the graphical method that the formation of the complex is accompanied by the elimination of one proton. Patterns were found of the influence of the nature of substituents in the organic compound on the ionization constants of acid groups and stability of complexes. Molar extinction coefficients, equilibrium constants of the formation reactions and instability constants for the complexes were calculated. The structure of complexes ...

1976-01-01

153

White oils for high voltage cables  

Energy Technology Data Exchange (ETDEWEB)

''S-220'' white oil is used currently to impregnate and fill high voltage cables for 110-500 kilovolts; it has high electrical characteristics and meets production and use standards. High pressure and cooling problems, however, require filling cables with lower viscosity oils, while insulation needs still demand high viscosity. The authors developed a new white oil similar to S-220 using a neutral oil made in producing sulfonate additives. The process involved vacuum distillation, low-temperature paraffination, sulfation with oleum, neutralizing with ammonium hydroxide and simultaneous extraction of sulfo-salts and contact purification. The lowest content of aromatic hydrocarbons was sought. Dielectric qualities varied with viscosity. Satisfactory thermooxidational capability was found at 50/sup 0/C with an oil of no less than 50 mm/sup 2//sec viscosity. The final white oil had no more than 2% aromatic hydrocarbons, thus assuring ...

1982-10-01

154

Synthesis and characterization of MoO_3 nanostructures by solution combustion method employing morphology and size control  

International Nuclear Information System (INIS)

Molybdenum oxide nanostructures were synthesized utilizing the solution combustion method where the ammonium molybdate powder and an organic additive were used as precursors. Different organic additives including ethylene diamine tetra-acetic acid (EDTA), polyethylene glycol 200 (PEG 200), sorbitol and urea were used as surfactants in order to investigate the effect of additive structure on morphology and particle size of products. Also various reaction parameters such as the additive/Mo molar ratio, concentration of metal ion in solution, pH of the reaction, and temperature of the synthesis media were changed to study effects on product morphology and size. Outcomes were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction, and Transmission Electron Microscopy (TEM) techniques. Results show a variety of MoO_3 nanoparticles and nanorods produced within the size range of 10-80 nm. Furthermore, microrods and microsheets were also obtained through ...

2010-05-01

155

Remediation of contaminated agricultural soils near a former Pb/Zn smelter in Austria: Batch, pot and field experiments  

International Nuclear Information System (INIS)

Metal contaminated crops from contaminated soils are possible hazards for the food chain. The aim of this study was to find practical and cost-effective measures to reduce metal uptake in crops grown on metal contaminated soils near a former metal smelter in Austria. Metal-inefficient cultivars of crop plants commonly grown in the area were investigated in combination with in-situ soil amendments. A laboratory batch experiment using 15 potential amendments was used to select 5 amendments to treat contaminated soil in a pot study using two Barley (Hordeum vulgare L.) cultivars that differed in their ability to accumulate cadmium. Results from this experiment identified 3 of these amendments for use in a field trial. In the pot experiment a reduction in ammonium nitrate extractable Cd (<41%) and Pb (<49%) compared to the controls was measured, with a concurrent reduction of uptake into barley grain (Cd < 62%, Pb < 68%). In the field extractable fractions ...

2006-11-01

156

Radiolabeling of a wound-inducible pyridoxal phosphate utilizing protein from tomato: evidence for its identification as ACC synthase  

International Nuclear Information System (INIS)

Aminocyclopropane 1-carboxylic acid (ACC) synthase, a pyridoxal phosphate utilizing enzyme, catalyzes the conversion of S-adenosylmethionine to ACC, the rate limiting step in the biosynthesis of the plant hormone, ethylene. Ethylene, besides being involved in normal plant growth processes, is also produced in response to stress, e.g. wounding, pathogen infection, etc. The authors report the partial purification (400 fold) of ACC synthase from wounded pink tomato pericarp by classical techniques including ammonium sulfate precipitation, ion exchange and phenyl sepharose chromatography. Further purification results in a decrease in specific activity apparently due to the instability of the enzyme and the low levels present in plant tissue. Radiolabeling of a pyridoxal phosphate-utilizing protein in the ACC synthase enriched fraction was achieved. Evidence that this radiolabeled protein is ACC synthase will be presented. Amino acid sequence determination of putative ...

1986-06-08

157

Preparation of CaWO{sub 4}:Ln{sup 3+} SiO{sub 2} (Ln=Tb, Dy and Ho) nanoparticles by a combustion reaction and their optical properties  

Energy Technology Data Exchange (ETDEWEB)

The CaWO{sub 4}:Ln{sup 3+} SiO{sub 2} (Ln=Tb, Dy and Ho) nanoparticles were synthesized via a combustion process at 800 {sup o}C, using citric acid as chelating agent and fuel, ammonium nitrate as fuel, boric acid as flux material and silica as supports. The persistent phosphor nanoparticles were characterized by X-ray diffraction (XRD), reflectance UV-vis and fluorescence spectroscopy (PL) and transmission electron microscopy (TEM) techniques. XRD patterns indicated that crystalline calcium tungstate with scheelite structure was produced. The reflectance UV-vis spectra showed the broad absorption band of WO{sub 4}{sup 2-} groups and the PL spectra showed the WO{sub 4}{sup 2-} wide excitation band, broad emission band of WO{sub 4}{sup 2-} and characteristic emissions of Ln{sup 3+} ions. The average particle sizes were determined by TEM, which are about 50 nm.

2010-11-15

158

Preparation of CaWO_4:Ln"3"+ SiO_2 (Ln=Tb, Dy and Ho) nanoparticles by a combustion reaction and their optical properties  

International Nuclear Information System (INIS)

The CaWO_4:Ln"3"+ SiO_2 (Ln=Tb, Dy and Ho) nanoparticles were synthesized via a combustion process at 800 "oC, using citric acid as chelating agent and fuel, ammonium nitrate as fuel, boric acid as flux material and silica as supports. The persistent phosphor nanoparticles were characterized by X-ray diffraction (XRD), reflectance UV-vis and fluorescence spectroscopy (PL) and transmission electron microscopy (TEM) techniques. XRD patterns indicated that crystalline calcium tungstate with scheelite structure was produced. The reflectance UV-vis spectra showed the broad absorption band of WO_4"2"- groups and the PL spectra showed the WO_4"2"- wide excitation band, broad emission band of WO_4"2"- and characteristic emissions of Ln"3"+ ions. The average particle sizes were determined by TEM, which are about 50 nm.

2010-11-01

159

Preparation and characterization of lithium-ion-conductive Li{sub 1.3}Al{sub 0.3}Ti{sub 1.7}(PO{sub 4}){sub 3} thin films by the solution deposition  

Energy Technology Data Exchange (ETDEWEB)

Li{sub 1.3}Al{sub 0.3}Ti{sub 1.7}(PO{sub 4}){sub 3} thin films were successfully prepared by the solution deposition using lithium acetate, aluminum nitrate, ammonium dihydrogen phosphate and titanium butoxide as starting materials. The structure, surface morphology, electrochemical window, and ionic conductivity of the films were studied by X-ray diffraction, scanning electron microscopy, cyclic voltammetry and AC impedance. The results showed that Li{sub 1.3}Al{sub 0.3}Ti{sub 1.7}(PO{sub 4}){sub 3} thin films annealed between 750 deg. C and 900 deg. C prepared by this method were well crystallized, homogenous and crack-free. The electrochemical window was beyond 2.4 V and the ionic conductivity was approximately 1.57x10{sup -5} S/cm at room temperature for the film annealed at 800 deg. C for 30 min.

2003-02-03

160

Preparation and characterization of lithium-ion-conductive Li_1_._3Al_0_._3Ti_1_._7(PO_4)_3 thin films by the solution deposition  

International Nuclear Information System (INIS)

Li_1_._3Al_0_._3Ti_1_._7(PO_4)_3 thin films were successfully prepared by the solution deposition using lithium acetate, aluminum nitrate, ammonium dihydrogen phosphate and titanium butoxide as starting materials. The structure, surface morphology, electrochemical window, and ionic conductivity of the films were studied by X-ray diffraction, scanning electron microscopy, cyclic voltammetry and AC impedance. The results showed that Li_1_._3Al_0_._3Ti_1_._7(PO_4)_3 thin films annealed between 750 deg. C and 900 deg. C prepared by this method were well crystallized, homogenous and crack-free. The electrochemical window was beyond 2.4 V and the ionic conductivity was approximately 1.57x10"-"5 S/cm at room temperature for the film annealed at 800 deg. C for 30 min.

2003-02-03

161

Innovative coal gas cleaning at Sparrows Point Coal Chemical Plant, Maryland for Bethlehem Steel Corporation  

Energy Technology Data Exchange (ETDEWEB)

In response to the Clean Coal II solicitation, Bethlehem Steel Corporation (BSC) submitted a proposal to the DOE in May 1988. The proposal submitted by BSC describes a Unique integration of commercial technologies developed by Davy/Still Otto to clean coke oven gas being produced at its Sparrows Point, Maryland steel plant. This innovative coke oven gas cleaning system combines secondary gas cooling with hydrogen sulfide and ammonia removal, hydrogen sulfide and ammonia recovery, ammonia destruction and sulfur recovery to produce a cleaner fuel gas for plant use. The primary environmental benefit associated with employing this innovative coke oven gas cleaning system is realized when the fuel gas is burned within the steel plant. Emissions of sulfur dioxide are reduced by more than 60 percent. The removal, recovery and destruction of ammonia eliminates the disposal problems associated with an unmarketable ammonium sulfate by-product. Significant reduction in ...

1990-01-01

162

Hydrous oxide activated charcoal  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a process for preparing of an ion exchanger, comprising: treating an ionically inert activated charcoal porous support with an aqueous solution of metal oxychloride selected from the group consisting of zirconium and titanium oxychlorides so as to impregnate the pores of the support with the solution; separating the treated support from excess metal oxychloride solution; converting the metal oxychloride to a hydrous metal oxide precipitate in the pores of the support at a pH above 8 and above the pH whereat the hydrous metal oxide and activated charcoal support have opposite zeta potentials and sufficient to hydrolyze the metal oxychloride. It also describes a process for preparing an ion exchanger comprising: treating granulated activated charcoal with a concentrated solution of a metal oxychloride from the group consisting of zirconium and titanium oxychlorides, degassing the mixture; and treating the resultant mixture with a base selected from the group ...

1987-09-08

163

Highly Porous, Water-Soluble, Superparamagnetic, and Biocompatible Magnetite Nanocrystal Clusters for Targeted Drug Delivery.  

Science.gov (United States)

Magnetic particles have become very promising materials for drug delivery. However, preparation of magnetite particles with high surface area, biocompatibility, strong magnetic response, and suitable particle size still remains a major challenge. In this report, magnetite nanocrystal clusters with high surface areas were fabricated through a solvothermal process by introducing ammonium acetate as a porogen and trisodium citrate as a surface modification agent. The porosity, which was controlled by the reactant concentration, has been investigated in detail. The surface area of the nanocrystal clusters was as high as 141?m(2) g(-1) . Ibuprofen, as a model drug, was entrapped into the magnetite carriers. The interfacial interaction between the carboxylic groups on the drug molecules and the carboxylate groups on the carriers enhanced the loading efficiency. Low cytotoxicity in MCF-7 cell and in vitro constant drug release behavior combined with the high drug loading ...

2011-09-27

164

Fluorimetric determination of uranium in certain refractory minerals, environmental samples and industrial waste materials  

International Nuclear Information System (INIS)

A simple sample decomposition and laser fluorimetric determination of uranium at trace level is reported in certain refractory minerals, like ilmenite, rutile, zircon and monazite; environmental samples viz. soil and sediments; industrial waste materials, such as, coal fly ash and red mud. Ilmenite sample is decomposed by heating with ammonium fluoride. Rutile, zircon and monazite minerals are decomposed by fusion using a mixture of potassium bifluoride and sodium fluoride. Environmental and industrial waste materials are brought into solution by treating with a mixture of hydrofluoric and nitric acids. The laser induced fluorimetric determination of uranium is carried out directly in rutile, zircon and in monazite minerals and after separation in other samples. The determination limit was 1 #mu#g x g"-"1 for ilmenite, soil, sediment, coal fly ash and red mud samples, and it is 5 #mu#g x g"-"1 for rutile, zircon and monazite. The method is also developed for the ...

2005-10-01

165

Effects of Soil Properties and Nitrogen Fertilization on Distribution of NO3-N in Soils of Eastern Poland  

British Library Electronic Table of Contents (United Kingdom)

The effects of anthropogenic (nitrogen fertilization) and natural [soil texture, pH content of humus, ammonium nitrogen (N-NH4), and the available forms of phosphorus (P), potassium (K), magnesium (Mg)] factors on nitrate nitrogen (NO3-N) content and distribution were shown. The dependencies between these factors and the content of NO3-N in soil were estimated in three soil layers: 0-30 cm; 31-60 cm; 61-90 cm. The research was carried out in 2004-2006, and the soil samples were taken from 411 places throughout eastern Poland in two seasons: spring and autumn. The concentration of NO3-N significantly depended on the year of investigation, season of the year, and depth of sampling. Distribution of NO3-N in the soil profile indicates possibility of NO3 leaching during winter and early spring....

2011-01-01

166

Drying characteristics and nitrogen loss of biogas digestate during drying process  

Energy Technology Data Exchange (ETDEWEB)

The cost of transporting biogas digestate can be decreased by reducing its water content. However, the digestate emits volatile compounds during drying. This study investigated the drying behaviour and the change of digestate composition. Drying took place in a hybrid solar/waste-heat dryer that used solar energy as well as waste heat from a combined heat and power unit (CHP) and the exhaust air of a microturbine. The experiment involved the use of 60 t of liquid digestate. Climatic conditions were measured inside and outside the drying hall. Dry matter (DM) and organic dry matter (ODM) were also measured on a daily basis. In addition, the energy consumption of waste and solar heat were recorded and related to the quantity of dried feedstock. The total nitrogen, ammonium, phosphate, potassium oxide, magnesium oxide and calcium oxide in the digestate were subjected to chemical analysis before and after the drying process. Losses of nitrogen were calculated. Specific ...

2010-07-01

167

Co-precipitated ZnAl2O4 spinel precursor as potential sintering aid for pure alumina system  

British Library Electronic Table of Contents (United Kingdom)

Ultra-fine ZnAl2O4 spinel hydrogel precursor synthesized from mixed salt solutions of Zn^2^+ and Al^3^+ ions using ammonium hydroxide-hexamethylenetetramine as basic media for co-precipitation was used as bonding material and sintering aid for pure alumina system. The hydrogel powder exhibited some well-defined ZnAl2O4 spinel phases at 800^oC. Alumina compacts were fabricated by incorporating small proportions of the precursor in alumina powder and firing at different temperatures (1350-1500^oC). The degree of densification was studied by measurement of fired shrinkage, apparent porosity, bulk density and cold crushing strength. Phase compositions and microstructural features of sintered samples were evaluated by XRD and SEM respectively. Addition of 0.2% hydrogel powder to alumina exhibit...

2010-01-01

168

Analysis of lagoon sludge characteristics for choice of treatment process  

Energy Technology Data Exchange (ETDEWEB)

The Korea Atomic Energy Research Institute has launched a decommissioning program of uranium conversion plant. One of the important tasks in the decommissioning program is the treatment of the sludge, which was generated during operation and stored in the two ponds of the lagoon. The treatment requires the volume reduction of lagoon sludges for the low cost of the program and the conversion of the chemical forms, including uranium, for the acceptance at the final disposal site. The physical properties, such as densities, were measured and chemical compositions and radiological properties were analyzed. The denitration was a candidate process which would satisfy the requirements for sludge treatment, and the characteristics of thermal decomposition and dissolution with water were analyzed. The main compounds of the sludge were ammonium and sodium nitrate from conversion plant and calcium nitrate, calcium carbonate from Ca precipitation and impurities of the yellow ...

2002-04-01

169

Actinide, strontium, and cesium removal from Hanford radioactive tank sludge  

International Nuclear Information System (INIS)

A pretreatment flowsheet was tested for separating key radionuclide components from the sludge stored in one of the high level waste tanks (B-110) at the Hanford Site; this sludge resulted primarily from the bismuth phosphate process, which was one of the three major plutonium separation processes used at Handford. This test involved (1) washing with water, (2) caustic leaching, (3) acid dissolution, (4) separation of transuranic elements (TRUs) by extraction with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide(CMPO), (5) separation of Sr by extraction with di-t-butylcyclohexano-18-crown-6, (6) separation of Cs from the acid-dissolved sludge solution by treatment with ammonium molybdophosphate (AMP), and (7) separation of Cs from the sludge wash and caustic leach solutions by ion exchange using a phenol-formaldehyde resin (CS-100). The results of the radionuclide separation steps indicated that the proposed flowsheet is a viable approach to pretreating ...

170

Acidity of H-Y zeolites: Role of extralattice aluminum  

Science.gov (United States)

The nature of extralattice aluminum and its effect on acidity in zeolites was studied. A series of zeolites (some commercial), dealuminated by various methods, were obtained having Si/Al ratios between 1.5 and 20. These were characterized using volumetric sorption, XRD, AA, NMR, and reaction studies. Samples dealuminated using ammonium hexafluorosilicate were found to contain little or no extralattice aluminum. In contrast, steam-dealuminated zeolites had large amounts of extralattice aluminum. In some cases a significant portion of the extralattice aluminum was unobservable by [sup 27]Al NMR, suggesting the existence of an aluminum species of low symmetry. Proton NMR indicated that all the protons were associated with the lattice aluminum atoms. Depending on the preparation history, different groups of H-Y zeolites exhibited different maxima in catalytic activity as a function of aluminum content. The maxima in catalytic activity for n-pentane cracking was found ...

1993-02-01

171

Uncovering the Mechanisms of Estrogen Effects on Hippocampal Function  

UK PubMed Central (United Kingdom)

Estrogens have direct effects on the brain areas controlling cognition. One of the most studied of these regions is the dorsal hippocampal formation, which governs the formation of spatial and...Full Text Available

2008-05-01

172

The inhibition of staphylococcus epidermidis biofilm formation by vancomycin-modified titanium alloy and implications for the treatment of periprosthetic infection  

UK PubMed Central (United Kingdom)

Peri-prosthetic infections are notoriously difficult to treat as the biomaterial implant is ideal for bacterial adhesion and biofilm formation, resulting in decreased antibiotic sensitivity....Full Text Available

2008-12-01

173

Star-formation triggers and chemical evolution  

Energy Technology Data Exchange (ETDEWEB)

Comparative studies of flocculent and grand-design spirals suggest that density waves are not the predominant trigger of star formation in most galaxies. Implications for chemical evolution are profound. It may be possible to ignore the details of the spiral-wave phenomenon in research aimed at unifying the chemical properties of spiral disks. 16 references.

1986-10-01

174

Osteopontin is elevated during neointima formation in rat arteries and is a novel component of human atherosclerotic plaques.  

UK PubMed Central (United Kingdom)

In an earlier report, we used differential cloning to identify genes that might be critical in controlling arterial neointima formation (Giachelli, C., N. Bae, D. Lombardi, M. Majesky, and S. Schwartz....Full Text Available

1993-10-01

175

Nonsteroidal Anti-Inflammatory Drugs for Wounds: Pain Relief or Excessive Scar Formation?  

UK PubMed Central (United Kingdom)

The inflammatory process has direct effects on normal and abnormal wound healing. Hypertrophic scar formation is an aberrant form of wound healing and is an indication of an exaggerated function of...Full Text Available

2010-01-01

176

Influence of pore structure in coke on CO and NO formation during coke combustion  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the investigation into the influence of coke pore structure on the formation of nitrogen oxides and carbon monoxide during the combustion of coke. Two samples of coke were compared; pulverized coke and lump coke.

1981-01-01

177

In Vitro Flower Bud Formation in Tobacco: Interaction of Hormones 1  

UK PubMed Central (United Kingdom)

External application of auxin and cytokinin is required for the formation of flower buds on thin-layer tissue explants of Nicotiana tabacum cv Samsun. Interaction between both plant...Full Text Available

1991-09-01

178

Identification of LRRc17 as a Negative Regulator of Receptor Activator of NF-?B Ligand (RANKL)-induced Osteoclast Differentiation*S?  

UK PubMed Central (United Kingdom)

Osteoblasts are the primary cells responsible for bone formation. They also support osteoclast formation from bone marrow precursors in response to osteotropic factors by inducing receptor activator...Full Text Available

2009-05-29

179

Hydrodynamics of primordial black hole formation: dependence on the equation of state  

Energy Technology Data Exchange (ETDEWEB)

An analysis is made of the manner in which the process of primordial black-hole formation and the subsequent accretion of gas depend on the equation of state. On the assumption that the process is spherically symmetric, the problem is solved numerically.

1980-03-01

180

Determination of bilayer membrane bending stiffness by tether formation from giant, thin-walled vesicles.  

UK PubMed Central (United Kingdom)

The curvature elastic modulus (bending stiffness) of stearoyloleoyl phosphatidylcholine (SOPC) bilayer membrane is determined from membrane tether formation experiments. R. E. Waugh and R. M. Hochmuth...Full Text Available

1989-03-01

181

Cytokinins and Flower Bud Formation in Vitro in Tobacco  

UK PubMed Central (United Kingdom)

Explants from flower stalks of Nicotiana tabacum L. were cultured on different cytokinins to induce flower bud formation. All cytokinins tested except zeatin and zeatin-riboside induced...Full Text Available

1990-03-01

182

Advances in metallography. Fortschritte in der Metallographie  

Energy Technology Data Exchange (ETDEWEB)

The 52 papers discuss the following subjects: 1. Preparation and structural development; 2. Structural constitution; 3. Structural formation and phase transition; 4. Structure and mechanical properties; 5. Structural formation of metallic and nonmetallic materials; 6. Quantitative metallography, and 7. Quality assurance.

1983-01-01

183

Phosphorus, nitrogen, and radionuclide retention and leaching from a Joel sand amended with red mud/gypsum  

International Nuclear Information System (INIS)

The leaching of phosphorus (P), nitrogen (N), and radionuclides "2"3"2Th, "2"2"6Ra, "2"2"8Ra, and "4"0K from Joel sands amended with red mud/gypsum (RMG) at 9 rates (0, 2, 4, 8, 16, 32, 64, 128, and 256 t/ha) was measured using columns. Intense leaching conditions (34 mm/day for 12 days) and a high rate of applied P (320 kg/ha as superphosphate) and N (680 kg/ha as ammonium nitrate) were used to simulate extremes of irrigated vegetable production on the Swan Coastal Plain. Addition of the highest rate of RMG (256 t/ha) reduced leaching of fertiliser P and ammonium-nitrogen (NH4-N) by 85% and 50%, respectively, compared with 0 t/ha after 12 days. At 64 t RMG/ha P leaching was reduced 50% compared with 0 t/ha. Nitrate-nitrogen (NO3-N) leaching was not affected by addition of RMG. Reduced leaching of NH4-N was attributed to an increase in cation exchange capacity of the soil with the addition of RMG. Bicarbonate-extractable P in the soil increased ...

185

The Effect of the Temperature to Which the Material is Heated ...  

Science.gov (United States)

... The Effect of the Temperature to Which the Material is Heated on the Process of Formation of Intermetallic Compounds in Magnetic Pulse Welding,. ...

1980-09-01

186

Survey of Biodegradation of Electronic Components and ...  

Science.gov (United States)

... This pinhole process may be similar to the formation of an oxide layer in aluminum electrolytic capacitors immersed in a borax solution. ...

1991-08-01

187

Protostar Formation in the Early Universe  

CERN Document Server

The nature of the first generation of stars in the Universe remains largely unknown. Observations imply the existence of massive primordial stars early in the history of the universe, and the standard theory for the growth of cosmic structure predicts that structures grow hierarchically through gravitational instability. We have developed an ab initio computer simulation of the formation of primordial stars that follows the relevant atomic and molecular processes in a primordial gas in an expanding universe. The results show that primeval density fluctuations left over from the Big Bang can drive the formation of a tiny protostar with a mass of just one percent that of the sun. The protostar is a seed for the subsequent formation of a massive primordial star.

2008-01-01

189

Honing the Dagger: The formation of a Standing Joint Special ...  

Science.gov (United States)

... Admiral Olson mentions the requirement for a standing joint task force headquarters in USSOCOM in order to fulfill the command's charter as a ...

2005-05-26

190

Formation and coarsening of Ga droplets on focused-ion-beam irradiated GaAs surfaces  

International Nuclear Information System (INIS)

We have investigated the formation and coarsening of Ga droplets on focused-ion-beam (FIB) irradiated GaAs surfaces. To separately examine formation and coarsening, Ga droplets were fabricated by Ga"+ FIB irradiation of GaAs substrates with and without pre-patterned holes. We determined the droplet growth rate and size distribution as a function of FIB energy following irradiation. The data suggest a droplet formation mechanism that involves Ga precipitation from a Ga-rich layer, followed by droplet coarsening via a combination of diffusion and Ostwald ripening or coalescence via droplet migration (dynamic coalescence).

2009-10-12

191

Estimation of static formation temperatures in geothermal wells  

Energy Technology Data Exchange (ETDEWEB)

Stabilized formation temperatures were estimated at different depths in 40 wells from the Los Humeros geothermal field, Mexico, using the Horner and the spherical radial flow (SRF) methods. The results showed that the Horner method underestimates formation temperatures, while the SRF method gives temperatures that are closer to the true formation temperatures. This was supported by numerical simulation of a combined circulation and shut-in period in several wells, and results for well H-26 are presented. Numerical reproduction of logged temperature is more feasible if an initial temperature profile based on the SRF method is employed instead of using an initial temperature profile based on the Horner method. (Author)

2003-05-01

192

Effect of cross rolling parameters on texture formation and parameters on texture formation and anisotropy of mechanical properties of (#alpha#+#beta#)-titanium alloy sheets  

International Nuclear Information System (INIS)

Formation of basis type texture at rolling of Ti + 6.0% Al + 1.5% V + 1.0% Mo system alloy with initial prismatic texture is investigated by means of X-ray techniques. Variations of mechanical features in titanium alloy sheets depending on temperature-deformation conditions of rolling are investigated. Main conditions for formation of the intensive basis textute in the investigated alloy sheets which provides for isotropic properties in sheet plane and for increased ductility are determined.

194

Combustion chemistry and formation of pollutants; Chimie de la combustion et formation des polluants  

Energy Technology Data Exchange (ETDEWEB)

This book of proceedings reports on 7 papers on combustion chemistry and formation of pollutants presented during the workshop organized by the `Combustion and Flames` section of the French society of thermal engineers. The chemistry of combustion is analyzed in various situations such as: turbojet engines, spark ignition engines, industrial burners, gas turbines etc... Numerical simulation is used to understand the physico-chemical processes involved in combustion, to describe the kinetics of oxidation, combustion and flame propagation, and to predict the formation of pollutants. (J.S.)

1996-12-31

195

CHAM_CLOUD_3 - HEASARC  

Science.gov (United States)

Main purpose of mapping observations of the cloud is to make clear the mechanism of star formation and star evolution. Scientific objectives are summarized ...

196

The Analysis of Turbulence and Rotation U-3M Torsatron Plasma During Transport Barriers Formation  

International Nuclear Information System (INIS)

The analysis of plasma density oscillations and ExB rotation of U-3M torsatron plasma was performed by UHR correlation reflectometry during the transport barrier formation. The connections between these characteristics and the phenomenon of inner and edge transport barrier formation were determined experimentally at the different values of HF power and plasma density.

2006-01-01

197

Nonuniqueness of self-propagating spiral galaxy models  

Energy Technology Data Exchange (ETDEWEB)

We demonstrate the nonuniqueness of the basic assumptions leading to spiral structure in self-propagating star formation models. Even in the case where star formation occurs purely spontaneously and does not propagate, we have generated spiral structure by adopting the radically different assumption where star formation is systematically inhibited.

1984-05-15

198

Modification of the AN/TGC-26 Multiple Address Processing Unit to Accept JANAP 128 Format.  

Science.gov (United States)

The Multiple Address Processing Unit (MAPU) of the AN/TGC-26 tape relay center was originally designed to process ACP 127 message format. With the advent of JANAP 128 as a standardized message format a pressing need was felt for a MAPU modification to all...

1977-01-01

199

Method of altering the permeability of a subterranean formation  

Science.gov (United States)

The production of water from a subterranean formation is reduced by contacting the formation with a water dispersible hydrophilic organic polymer having a molecular weight greater than 100,000 and containing carboxyl functionality and a crosslinking composition comprising water, a zirconium compound having a value of 4+, an alpha-hydroxy acid and an amine compound.

1985-06-25

200

Formation of streamers in nitrogen and dry air; Vorming van streamers in stikstof en lucht  

Energy Technology Data Exchange (ETDEWEB)

The results of a time-resolved study of the avalanche and streamer formation phases leading to breakdown in atmospheric nitrogen and dry air. Results of experiments and two-dimensional simulations are presented. It is shown what processes are responsible for the formation of a streamer. The trends of externally measured quantities correspond with those predicted by our model. 3 figs., 5 refs.

1997-01-01

201

Device for laying cut peat in a drying formation  

Energy Technology Data Exchange (ETDEWEB)

A device for laying cut peat in drying formations is proposed consisting of separate compartments, reinforced on a common frame and with mechanisms for both vertical and horizontal mixing. In order to intensify the drying process, within the scope of laying cut peat, uniform clearances and spacing in formations is applied. The mixing compartments are joined in sections with capabilities for separate mixing in each unit. The compartments are joined together by hinges and can be turned 180 degrees on the hinges horizontal to the plane.

1980-06-17

202

Aspen Winter Conference Series  

Science.gov (United States)

(B204) The meeting will bring together observers and theorists in a highly interactive format, to further connect the local and cosmological star formation communities. Forward looking talks, aimed at the other communities, will survey terminology, achievements, problems and aspirations. Discussion will focus on the definition of the key questions, how the different communities can help each other, and preparations for the incorporation of realistic star formation into cosmological simulations.

1999-01-01

203

Time-resolved neutron diffraction study of the superconducting phase formation process in the Bi(PB)-Sr-Ca-Cu-O system  

Energy Technology Data Exchange (ETDEWEB)

The results of real-time neutron diffraction measurements during the superconducting phase formation process in the Bi(Pb)-Sr-Ca-Cu-O system are reported. A Sr-Ca-Cu-O type precursor, with the same stoichiometry as the 2223 phase, was used as starting material, and the temperature range favorable to the formation of the 2223 phase was investigated. The diffraction patterns were processed by a multiphase Rietveld refinement. The formation and decomposition of the 2201 and 2212 phases were directly observed. Experimental evidence on the existence of a partially melted phase in the range 855-860[degrees]C, involved in the formation of the 2223 phase, is discussed. 14 refs., 9 figs., 1 tab.

1993-08-01

204

Time-resolved neutron diffraction study of the superconducting phase formation process in the Bi(PB)-Sr-Ca-Cu-O system  

International Nuclear Information System (INIS)

The results of real-time neutron diffraction measurements during the superconducting phase formation process in the Bi(Pb)-Sr-Ca-Cu-O system are reported. A Sr-Ca-Cu-O type precursor, with the same stoichiometry as the 2223 phase, was used as starting material, and the temperature range favorable to the formation of the 2223 phase was investigated. The diffraction patterns were processed by a multiphase Rietveld refinement. The formation and decomposition of the 2201 and 2212 phases were directly observed. Experimental evidence on the existence of a partially melted phase in the range 855-860 degrees C, involved in the formation of the 2223 phase, is discussed. 14 refs., 9 figs., 1 tab.

205

Redistribution of implanted dopants after metal-silicide formation  

Science.gov (United States)

The redistribution of implanted As and Sb following metal-silicide formation of Pt, Pd, and Ni has been studied. The phases of the silicides used were PtSi, Pd/sub 2/Si, and NiSi. Investigations with Rutherford backscattering analysis showed that after the formation of the silicides, the Sb was always found in the silicide layer near the surface of the samples, whereas PtSi and Pd/sub 2/Si caused a partial rejection of As for implanted doses of 2 x 10/sup 15/ cm/sup -2/ and higher. No rejection of As was found after the formation of NiSi. The results are discussed in terms of solid solubilities and impurity-metal compound formation. The data presented has implications in the fabrication of Ohmic contacts and the adjustments of the heights of Schottky barriers on silicon.

1978-12-01

206

Redistribution of implanted dopants after metal-silicide formation  

International Nuclear Information System (INIS)

The redistribution of implanted As and Sb following metal-silicide formation of Pt, Pd, and Ni has been studied. The phases of the silicides used were PtSi, Pd_2Si, and NiSi. Investigations with Rutherford backscattering analysis showed that after the formation of the silicides, the Sb was always found in the silicide layer near the surface of the samples, whereas PtSi and Pd_2Si caused a partial rejection of As for implanted doses of 2 x 10"1"5 cm"-"2 and higher. No rejection of As was found after the formation of NiSi. The results are discussed in terms of solid solubilities and impurity-metal compound formation. The data presented has implications in the fabrication of Ohmic contacts and the adjustments of the heights of Schottky barriers on silicon.

207

Nanoparticle formation during laser ablation of metals at different pressures of surrounding noble gases  

Energy Technology Data Exchange (ETDEWEB)

We demonstrate that the nanoparticle formation during laser ablation of metals by short (of a few tens of ps) laser pulses strongly depends on the concentration of surrounding gas. While, at vacuum conditions, nanoparticle formation shows very ''sharp'' atomic force microscope images of aggregated clusters, following with clear appearance of plasmon resonance on the absorption spectra of deposited films, an addition of gas particles starts to decrease the probability of cluster formation. This process shows a threshold for both helium (33 torr) and xenon (12 torr) above which no surface plasmon resonance and correspondingly no observable nanoparticles on the deposited surfaces were detected. The destruction of nanoparticle formation was attributed to the negative influence of surrounding gas particles on ablated particles aggregation. (orig.)

2010-07-15

208

KEGGtranslator: visualizing and converting the KEGG PATHWAY database to various formats  

British Library Electronic Table of Contents (United Kingdom)

Summary: The KEGG PATHWAY database provides a widely used service for metabolic and nonmetabolic pathways. It contains manually drawn pathway maps with information about the genes, reactions and relations contained therein. To store these pathways, KEGG uses KGML, a proprietary XML-format. Parsers and translators are needed to process the pathway maps for usage in other applications and algorithms. We have developed KEGGtranslator, an easy-to-use stand-alone application that can visualize and convert KGML formatted XML-files into multiple output formats. Unlike other translators, KEGGtranslator supports a plethora of output formats, is able to augment the information in translated documents (e.g. MIRIAM annotations) beyond the scope of the KGML document, and amends missing components to fr...

2011-01-01

209

Adding channels with PSBT format at 40Gbit/s in an existing 10Gbit/s optical network  

British Library Electronic Table of Contents (United Kingdom)

Until recently, the wavelength-division-multiplexed (WDM) transmission system has reached record capacities and distances due to innovations such as FEC (Forward Error Correction), distributed Raman amplification, new transmission fiber and advanced optical format. Optical-communication systems exclusively employed conventional On-Off Keying signals in either Non-Return-To-Zero (NRZ) or Return-To-Zero (RZ) format. Recently a number of advanced modulation formats have attracted attention. Some of these formats carry information through On-Off-Keying but also modulate the optical phase in order to enhance the robustness of signal to chromatic dispersion, optical filtering and non-linearities. Through extensive sets of simulation results, we showed that it is possible to replace a channel wit...

2011-01-01

210

A study of methyl formate in astrochemical environments  

CERN Document Server

Several complex organic molecules are routinely detected in high abundances towards hot cores and hot corinos. For many of them, their paths of formation in space are uncertain, as gas phase reactions alone seem to be insufficient. In this paper, we investigate a possible solid-phase route of formation for methyl formate (HCOOCH3). We use a chemical model updated with recent results from an experiment where simulated grain surfaces were irradiated with 200 keV protons at 16 K, to simulate the effects of cosmic ray irradiation on grain surfaces. We find that this model may be sufficient to reproduce the observed methyl formate in dark clouds, but not that found in hot cores and corinos.

2011-01-01

211

Geology of the central Roan Plateau area, northwestern Colorado  

Energy Technology Data Exchange (ETDEWEB)

The geology of the central Roam Plateau area in the south-central part of the Piceance Creek basin, comprising four 7.5-minute quadrangles, is described. Subsurface rocks penetrated by drill holes include the Mancos Shale and Mesaverde Formation of Later Cretaceous age, and parts of the Wasatch Formation of Paleocene and Eocene age, and Green River Formation of Eocene age. Exposed rocks, aggregating as much as 4,550 feet in thickness, are all Eocene in age and include the upper part of the Wasatch Formation , and the Green River and Uinta formations. The Green River and Uinta formations are extensively intertongued. Surficial deposits of Quaternary age include alluvium, talus, slopewash, and landslides. Two northwesterly trending folds, the Clear Creek Syncline and the Crystal Creek anticlinal nose, are present in the northern part of the area. There are no ...

1992-01-01

212

Analysis on depositional system and discussion on ore-formation conditions of channel sandstone type uranium deposit. Taking Dongsheng area, Ordos meso-cenozoic basin as an example  

International Nuclear Information System (INIS)

Applying the theory of depositional system, the depositional facies and depositional systems of the Zhiluo Formation in Dongsheng area are systematically analysed, and the authors proposed that sediments of the Zhiluo Formation are of fluvial facies, and streams of the Zhiluo time experienced three evolution stages, namely: the early braided stream, the middle low sinuosity meandering stream and the late high sinuosity meandering stream. Based on features of paleoclimatic evolution, the Zhiluo Formation is divided into two lithological members. The lower lithological member consists of sediments of braided and low sinuosity meandering streams under humid-ward paleoclimatic conditions forming grey sedimentary formation. The upper member is composed of sediments of meandering streams under arid-hot paleoclimatic conditions representing complex-colored (mainly red) sedimentary ...

2003-03-01

213

Long term mineralogical changes in salt formations due to water and brine interactions  

International Nuclear Information System (INIS)

Four very common long term mineralogical changes in salt formations are discussed in the view of the safety considerations for underground repositories. Two of these processes, the 'Hartsalz' and 'Carnallite' dissolution were studied in two scale in situ experiments. The results are presented and compared with the results of the geochemical modelling with the computer code EQ3/6. Furthermore the reactions leading to the formation of the gypsum cap rock on the top of the Zechstein salt formations and to the polyhalitization of anhydrite are discussed. Geological field observations and mineral assemblages agree well with the results of the geochemical modelling employing the Pitzer formalism along with the Harvie, Moller and Weare database. We conclude that once the mechanisms of the chemical reactions are well understood it becomes possible to evaluate realistically whether such processes, when encountered in the repository, ...

1994-09-01

214

Application of quantitative sedimentology in the characterization of subsurface reservoirs and outcrop analogs  

Energy Technology Data Exchange (ETDEWEB)

The thesis deals with methods of describing the reservoir rock in central oil and gas fields on the Norwegian continental shelf. Methods of enhancing the level of recovery are dealt with. Following topics are given: Sand body dimensions and infill sequences of stable, humid-climate delta plain channels; minipermeameter-based study of permeability trends in channel sand bodies; significance of tidal cyclicity for modelling of reservoir heterogeneities in the lower Jurassic Tilje Formation, mid-Norwegian shelf; geometry and facies of large-scale flow units in fluvial-dominated fan-delta-front sequences; quantified fluvial architecture in ephemeral stream deposits of the Esplugafreda Formation (Palaeocene), Tremp-Graus Basin, northern Spain; the Safari project - collection and storage of field analogue data for quantitative reservoir modelling; sedimentary architecture of field analogues for reservoir information (SAFARI): a case study of the ...

1994-12-31

215

Study on high-resolution sequence stratigraphy framework of uranium-hosting rock series in Qianjiadian sag  

International Nuclear Information System (INIS)

The ore-hosting Yaojia Formation is composed of a set of braided stream medium-fine grained sediments. Guided by the basic theory of high-resolution sequence stratigraphy, and based on the core observation, the analysis of chemical composition of rocks, and data of natural potential logging and apparent resistivity logging, the authors have set up the high-resolution sequence stratigraphy framework of the ore-hosting Yaojia Formation, and discussed the relation of the stratigraphic structure of the middle cycle, as well as the paleotopography, the micro-facies to the formation of uranium deposit. (authors)

2005-07-01

216

Star Formation in the Outer Disks of Spiral Galaxies  

Science.gov (United States)

This is a study done in collaboration with Deidre Hunter at Lowell Observatory studying star formation in two luminous spiral galaxies NGC 801 and UGC 2885. We used ultra-deep H? images taken at the KPNO 2.1 m telescope. We compare these data to stellar images at various wavelengths and to HI maps to determine the extent of star formation activity into the outer disk in these galaxies and its relationship to the gas and older stars. TW is grateful for an REU internship during the summer of 2010 at Northern Arizona University, funded by NSF through grant AST-1004107.

2011-01-01

217

Silicidation in Pd/Si thin film junction-Defect evolution and silicon surface segregation  

Energy Technology Data Exchange (ETDEWEB)

Depth resolved positron annihilation studies on Pd/Si thin film system have been carried out to investigate silicide phase formation and vacancy defect production induced by thermal annealing. The evolution of defect sensitive S-parameter clearly indicates the presence of divacancy defects across the interface, due to enhanced Si diffusion beyond 870 K consequent to silicide formation. Corroborative glancing incidence X-ray diffraction (GIXRD), Auger electron spectroscopy (AES) and Rutherford backscattering spectrometry (RBS) have elucidated the aspects related to silicide phase formation and Si surface segregation.

2007-09-25

218

Investigation of formation of Sn-PM tetracycline and Sn-PM-tetracycline-_9_9Tc complexes  

International Nuclear Information System (INIS)

The formation and stability constants of the [sup(99m)Tc]PM tetracycline have been investigated by the potentiometric method. The pK value of the complex formed was measured as pK = 5.49 +- 0.19. The spectrophotometric study has been performed on the formation of a complex of Sn(II) and TcO"4"- in the presence of PM Tetracycline. This study shows that Sn(II) forms with PMT a complex at a mole ratio of 1:1. The molar extinction coefficients of the Sn-PMT and [_9_9Tc]PMT complexes have been measured. (author).

1983-01-01

219

Gold and gold-silver core-shell nanoparticle constructs with defined size based on DNA hybridization  

Energy Technology Data Exchange (ETDEWEB)

Nanoparticles represent versatile building blocks in material science and nanotechnology. Thereby, the defined assembly of nanostructures (13 and 56 nm in diameter, respectively) is of significant importance. Short DNA sequences can be bound to the nanoparticle surface thus enabling highly specific DNA hybridization-driven events that direct the formation of nanoparticle constructs.In this paper, examples for the defined formation of gold nanoparticle constructs are demonstrated. In addition, gold-silver core-shell nanoparticles are introduced as further building blocks for the hybridization-controlled formation of nanoparticle constructs.

2009-04-15

220

Formation evaluation MWD enters new capability realm  

Energy Technology Data Exchange (ETDEWEB)

Recent industry advances in formation evaluation measurement-while-drilling (FEMWD) have been achieved in well log data acquisition quality and in geosteering drilling applications. This paper presents new technology as applied by Baker Hughes INTEQ which includes: geosteering techniques which help navigate through horizontally drilled reservoirs including improved quality dual propagation resistivity, neutron-porosity and formation-density measurements; predictive modeling of tool responses in reservoir geosteering applications; environmental computer modeling which aids interpretation, including tool eccentering; and new measurement enhancements.

1994-11-01

221

First investigations of complex formation of At(I) with phosphorous organic compounds  

Energy Technology Data Exchange (ETDEWEB)

Reaction of At(I) with triphenylphosphine, triethylphosphite and tri-n-octylphosphine oxide was investigated in ethanolic solution by means of electromigration. A cationic complex with triphenylphosphine was identified being stable at pH = 1,9 in the concentration range of the ligand between c = 10{sup -5} to 10{sup -3} M. At a higher ligand concentration and at pH>2, the reduction effect of phosphine is superimposed on the complex formation. Complex formation is confirmed by ligand exchange reactions with Br{sup -} and I{sup -}. A comparatively weak complex is formed by triethylphosphite and At(I). No compound is formed by tri-n-octylphosphine oxide and At(I). (orig.).

1989-01-01

222

First investigations of complex formation of At(I) with phosphorous organic compounds  

International Nuclear Information System (INIS)

Reaction of At(I) with triphenylphosphine, triethylphosphite and tri-n-octylphosphine oxide was investigated in ethanolic solution by means of electromigration. A cationic complex with triphenylphosphine was identified being stable at pH = 1,9 in the concentration range of the ligand between c = 10"-"5 to 10"-"3 M. At a higher ligand concentration and at pH>2, the reduction effect of phosphine is superimposed on the complex formation. Complex formation is confirmed by ligand exchange reactions with Br"- and I"-. A comparatively weak complex is formed by triethylphosphite and At(I). No compound is formed by tri-n-octylphosphine oxide and At(I). (orig.).

223

The structure of molecular clouds - III. A link between cloud structure and star formation mode  

British Library Electronic Table of Contents (United Kingdom)

Abstract We analyse extinction maps of nearby giant molecular clouds to forge a link between driving processes of turbulence and modes of star formation. Our investigation focuses on cloud structure in the column density range above the self-shielding threshold of 1-mag AV and below the star formation threshold - the regime in which turbulence is expected to dominate. We identify clouds with shallow mass distributions as cluster forming. Clouds that form stars in a less clustered or isolated mode show a steeper mass distribution. Structure functions prove inadequate to distinguish between clouds of different star formation mode. They may, however, suggest that the turbulence in the average cloud is governed by solenoidal forcing. The same is found using the -variance analysis which also in...

2011-01-01

224
225

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

226

The Factors Determining the Level of Virus Production. Report ...  

Science.gov (United States)

... After formation of the monolayer (usually in 48 hours), the growth medium was poured off, and the cells washed twice with a Henkes solution and ...

1971-12-02

228

T-bet controls severity of hypersensitivity pneumonitis  

UK PubMed Central (United Kingdom)

Hypersensitivity Pneumonitis (HP) is an interstitial lung disease that develops following repeated exposure to inhaled environmental antigens. The disease is characterized by alveolitis, granuloma formation...Full Text Available

229

Surface and Interface Study of PdCr/SiC Schottky Diode Gas Sensor ...  

Science.gov (United States)

indications of the formation of palladium silicides. 2, 4. It has been reported .... At room temperature, palladium silicides formed in a relatively narrow interface ...

230

State II Dissociation Element Formation Following Activator Excision in Maize  

UK PubMed Central (United Kingdom)

Active Activator (Ac) elements undergo mutations to become nonautonomous Dissociation (Ds) elements at a low frequency. To understand...Full Text Available

2007-10-01

231

South Downs Lifescapes Joint Data Management  

Environmental Research Database

ObjectivesTo determine what biodiversity data is held by record centres for the South Downs Lifescapes pilot area and the format in which it is stored.

2004-01-31

232

Scenario Authoring and Visualization for Advanced Graphical ...  

Science.gov (United States)

... TEXT FORMAT (XML-MTF)....34 1. Public Beta Release 1.02 of MTF2XML Converter.....35 G ...

2001-09-01

233

SURFACE AND INTERFACE PROPERTIES OF PdCr/SiC SCHOTTKY DIODE GAS ...  

Science.gov (United States)

The formation of palladium silicides near the interface may decrease hydrogen solubility at the effective metal/semiconductor ...

234

Report Out of the C4I Study Group  

Science.gov (United States)

... Tactical Electronic Intelligence (TACELINT), and a variety of other messages in US Message Text Format (USMTF) in both JANAP 128 and DOI 103 ...

2001-06-01

235

Real Time Trajectory Planning for Groups of Unmanned ...  

Science.gov (United States)

... kinematic model for the robots and designed ... theoretic approach for modeling mobile robot teamn formations". ... "UUV teams, control from a biological ...

2005-08-22

236

Radius of thawing around an injection well and time of complete freezeback  

Science.gov (United States)

An approximate method of calculating the radius of thawing around an injection well is presented. The method is based on the assumption that for a cylindrical system the position of the phase interface in the Stefan problem can be approximated through two functions: one function determines the position of the melting-temperature isotherm in the problem without phase transitions and the second function does not depend on time. The adjusted heating time concept was used to describe the first function. The second function is a known analytical relationship and is expressed in terms of ice content, thermal properties of thawed/frozen formations, formation temperature and the temperature of the injected fluid. Simple approximate formulae are suggested to estimate the duration of the freezeback period. To verify the proposed formulae, the results of numerical solutions were used. An example which shows that the duration of the 'safety period' (free ...

2006-06-01

237

Production of Amylase in Liquid Culture by a Strain of Aspergillus oryzae  

UK PubMed Central (United Kingdom)

The effect of different media and pH on the formation of amylase by Aspergillus oryzae EI 212 is described. Depending upon the composition of the medium and growth...Full Text Available

1970-04-01

238

Photodegradation of polypropylene/polystyrene blends: Styrene-butadiene-styrene compatibilisation effect  

British Library Electronic Table of Contents (United Kingdom)

The mutual influence between the PP/PS polymer blend components during UV photodegradation was studied. Polypropylene (PP) and polystyrene (PS) have different photodegradation mechanisms, due to the larger UV absorption of polystyrene and formation of more stable tertiary carbon radicals. To compare the stabilities the kinetics of carbonyl formation was measured in different blend compositions. The results show that polystyrene presented a faster carbonyl formation than polypropylene, while the blends display faster kinetics than the isolated components. The kinetics of carbonyl formation of the blends was a function of polypropylene content. This result is unexpected if one considers the behaviour of each component alone. The kinetics and mechanism of UV degradation can be only explained ...

2008-01-01

239

Palynostratigraphy and palaeoenvironment of the Middle Jurassic Sortehat Formation (Neill Klinter Group), Jameson Land, East Greenland  

Energy Technology Data Exchange (ETDEWEB)

The grey-black mudstones of the Sonehat Formation form part of the Middle Jurassic fill of the Jameson Land Basin in East Greenland. The formation is exposed in the southernmost part of the north south-trending, Mesozoic rift system in East Greenland that was part of the epeiric seaway betaveen East Greenland and Norway. Sedimentological observations of the Sortehat Formation indicate deposition in an offshore marine setting that was typically low energy and periodically oxygen-deficient but was influenced by storm currents on occasion. Detailed palynological studies of the Sortehat Formation have resulted in the definition of theee palynological assemblage zones recognised at four localities, namely Enhjoerningen Dal and Pelion (north Jameson Land), the type section at Sortehat (central Jameson Land) and Albuen at Neill Klinter along Hurry Inlet (south-east Jameson Land). In stratigraphic order, these ...

2003-07-01

240

NASA - Spitzer Sees Spider Web of Stars  

Science.gov (United States)

star formation. To either side of the center, a small bar of dust and gas is helping to fuel the new stars. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the...

2011-07-20

241

Measurements of the concentration and composition of nuclei for cirrus formation  

UK PubMed Central (United Kingdom)

This article addresses the need for new data on indirect effects of natural and anthropogenic aerosol particles on atmospheric ice clouds. Simultaneous measurements of the concentration and composition...Full Text Available

2003-12-09

242

Mass public health programmes and the obligations of sponsoring and participating organisations  

UK PubMed Central (United Kingdom)

The obligations of organisations associated with policy formation and implementation of international mass public health programmes are explored. Lines of responsibility are considered to become unclear...Full Text Available

2006-10-01

244

Lithium abundance in two halo stars  

Energy Technology Data Exchange (ETDEWEB)

Observation of lithium lines in two halo stars could bring some information about /sup 7/Li abundance at the time of the formation of the galaxy.

1981-10-05

245

Late Life-Threatening Hemorrhage after Percutaneous Tracheostomy  

UK PubMed Central (United Kingdom)

Purpose. Formation of a tracheoinnominate artery fistula (TIF) and consecutive hemorrhage is a rare and life-threatening complication with high mortality. Warning symptoms can...Full Text Available

2011-01-01

246

Humoral BMP-2 is Sufficient for Inducing Breast Cancer Microcalcification  

UK PubMed Central (United Kingdom)

Microcalcifications are an important diagnostic marker for breast cancer on mammograms, yet the mechanism of their formation is poorly understood. Indeed, there is presently no short-latency,...Full Text Available

2008-01-01

247

Heat shock proteins as emerging therapeutic targets  

UK PubMed Central (United Kingdom)

Chaperones (stress proteins) are essential proteins to help the formation and maintenance of the proper conformation of other proteins and to promote cell survival after a large variety of environmental...Full Text Available

2005-11-01

248

Formation of particles in combustion of biofuels  

International Nuclear Information System (INIS)

Biomass combustion is an important part in a sustainable energy system, but as well a source of submicron (particles < 1 #mu#m) particles in the air. Consequently, to obtain a good air quality together with increased biomass combustion there is a need for a better understanding of particle formation. This work is a part of a larger project about formation and emissions of particles from biofuel combustion. The report includes the work performed in the project during the year 2004. The aim of the project is to describe the release of inorganic components, which cause particle emissions, during combustion of single fuel particles of biofuel, e.g. wood pellets. The work is carried out by emission measurements, systematic combustion experiments and modelling work. The results are expected to contribute to the understanding of which parameters that influence the formation of fine particles and thus gain a better insight into ...

249

Fabrication and characterization of Pd/Ag alloy hollow spheres by the solvothermal method  

Energy Technology Data Exchange (ETDEWEB)

Pd/Ag alloy hollow spheres have been synthesized in ethylene glycol solution by the solvothermal method and have been characterized extensively. TEM results have revealed the formation of Pd/Ag hollow spheres. Moreover, HRTEM results confirmed the formation of Pd/Ag alloy spheres, where the lattice fringe spacing is 0.229 nm corresponding to the (111) plane of Pd/Ag alloy. SEM, XRD and UV-vis results have further suggested the formation of alloy hollow spheres. The preliminary results showed the reaction time may be an importance factor influencing the formation of Pd/Ag alloy hollow spheres.

2008-03-15

250

Evaluating concentration estimation errors in ELISA microarray experiments  

UK PubMed Central (United Kingdom)

BackgroundEnzyme-linked immunosorbent assay (ELISA) is a standard immunoassay to estimate a protein's concentration in a sample. Deploying ELISA in a microarray format permits simultaneous...Full Text Available

251

Endothelial von Willebrand factor regulates angiogenesis  

UK PubMed Central (United Kingdom)

The regulation of blood vessel formation is of fundamental importance to many physiological processes, and angiogenesis is a major area for novel therapeutic approaches to diseases from ischemia to...Full Text Available

2011-01-20

252

Dietary plant materials reduce acrylamide formation in cookie and starch-based model systems  

British Library Electronic Table of Contents (United Kingdom)

Abstract BACKGROUND: Dietary plant materials have attracted much attention because of their health benefits to humans. Acrylamide is found in various heated carbohydrate-rich foods. Our previous results showed that crude aqueous extracts from diverse dietary plants and some phenolic compounds could mitigate acrylamide formation in an asparagine-glucose model system. Based on our previous study, several plant materials were selected to further investigate their inhibitory effects on acrylamide formation in cookies and starch-based model systems. RESULTS: Addition of raw powders from selected dietary plants and their crude aqueous extracts could considerably reduce acrylamide formation in both cookie and potato starch-based models. Aqueous extracts of clove at 4% caused the largest reduction...

2011-01-01

253

Diagenesis and porosity development in the carbonate reservoirs in the Ordovician Majiagou Formation, northern Ordos Basin, China  

Energy Technology Data Exchange (ETDEWEB)

The carbonate rocks of the Lower Ordovician Majiagou Formation represent important hydrocarbon reservoirs in the Ordos basin in the western part of the North China plate. Cores and thin sections from more than 60 wells were examined. The main reservoir in the Majiagou Formation consists of fine crystalline dolomite, which was altered by meteoric water during an extended subaerial exposure. Three phreatic zones have been identified in the Majiagou Formation in the northern part of the basin. Oxygen isotopes and fluid inclusion microthermometry data indicates that the porosity developed during the early karst event was considerably reduced by the late-stage, coarse crystalline calcite cements that appear to be related to hydrothermal fluids during deep burial. It was concluded that the main factors that determine the porosity and permeability of these carbonate reservoirs are dolomitization, karstification, and calcite ...

2006-07-01

254

Dense and diffuse gas in dynamically active clouds  

CERN Document Server

We investigate the chemical and observational implications of repetitive transient dense core formation in molecular clouds. We allow a transient density fluctuation to form and disperse over a period of 1 Myr, tracing its chemical evolution. We then allow the same gas immediately to undergo further such formation and dispersion cycles. The chemistry of the dense gas in subsequent cycles is similar to that of the first, and a limit cycle is reached quickly (2 - 3 cycles). Enhancement of hydrocarbon abundances during a specific period of evolution is the strongest indicator of previous dynamical history. The molecular content of the diffuse background gas in the molecular cloud is expected to be strongly enhanced by the core formation and dispersion process. Such enhancement may remain for as long as 0.5 Myr. The frequency of repetitive core formation should strongly determine the level of background ...

2006-01-01

255

Crystallization after intravitreal ganciclovir injection  

UK PubMed Central (United Kingdom)

Purpose:To report crystal formation as a complication of intravitreal ganciclovir injection.Patients and methods:A 73-year-old female patient with...Full Text Available

2010-01-01

256

Crystal Chemistry of Ceramic/Mineral Systems  

Science.gov (United States)

... 1. Reeber, RR, Kusy, RP, Yu, N. and Chu, WK " Formation of a Solid Lubricant in Boron Carbide by Nitrogen Ion Implantation and Laser Annealing ...

1992-12-08

258

Cloud Formation and Dynamics in Cool Dwarf and Hot Exoplanetary Atmospheres  

CERN Document Server

The lowest-mass stars, brown dwarfs and extrasolar planets present challenges and opportunities for understanding dynamics and cloud formation processes in low-temperature atmospheres. For brown dwarfs, the formation, variation and rapid depletion of photospheric clouds in L- and T-type dwarfs, and spectroscopic evidence for non-equilibrium chemistry associated with vertical mixing, all point to a fundamental role for dynamics in vertical abundance distributions and cloud/grain formation cycles. For exoplanets, azimuthal heat variations and the detection of stratospheric and exospheric layers indicate multi-layered, asymmetric atmospheres that may also be time-variable (particularly for systems with highly elliptical orbits). Dust and clouds may also play an important role in the thermal energy balance of exoplanets through albedo effects. For all of these cases, 3D atmosphere models are becoming an increasingly essential ...

2009-01-01

259

Chemical and physical conversion in cold atmosphere and the effect of radiation  

Energy Technology Data Exchange (ETDEWEB)

The project is focusing on the formation and growth mechanisms of atmospheric aerosol and cloud droplets. Both aerosol particles and cloud droplets affect strongly on the atmospheric radiation fluxes by scattering and absorption. The droplet formation results from physical and chemical processes occurring simultaneously. The studies concerning the tropospheric cloud droplet formation, laboratory experiments with a cloud chamber and stratospheric cloud formation are summarized. The recent studies summarized in this presentation indicate that both aerosol particles and cloud droplets have a significant role in climatic change and ozone depletion problems. The anthropogenic emissions of gaseous and particulate pollutants change the properties of atmospheric aerosols and cloud droplets. The research in this field will be continued and more quantitative understanding based both experimental and theoretical ...

1996-12-31

260

Cellular and Molecular Mechanisms of Bone Remodeling*  

UK PubMed Central (United Kingdom)

Physiological bone remodeling is a highly coordinated process responsible for bone resorption and formation and is necessary to repair damaged bone and to maintain mineral homeostasis. In addition to...Full Text Available

2010-08-13

262

Calcium-Actin Waves and Oscillations of Cellular Membranes  

UK PubMed Central (United Kingdom)

AbstractWe propose a mechanism for the formation of membrane oscillations and traveling waves, which arise due to the coupling between the actin cytoskeleton and the calcium flux through...Full Text Available

2009-09-16

263

Benefits of Using the Photosimulation Laboratory Environment ...  

Science.gov (United States)

... with the ability to capture imagery in raw 24-bit format, combined with large memory storage devices enable high resolution imagery to be captured ...

2002-08-01

264

Autocatalytic nucleation of omega phase in a beta-titanium alloy  

International Nuclear Information System (INIS)

Observations concerned with the formation of isothermal #omega# in the beta-titanium alloy RMI (38-6-44) are presented as part of a more general study of the aging characteristics of the alloy.

265

Assessment of the oil source-rock potential of the Pedregoso Formation (Early Miocene) in the Falcon Basin of northwestern Venezuela  

British Library Electronic Table of Contents (United Kingdom)

The early Miocene Pedregoso Formation is one of the numerous formations rich in organic matter within the stratigraphic record of the Urumaco Trough, in the central area of the Falcon Basin. Due to its lithological characteristics and stratigraphic position, this formation is of great interest regarding the basin's petroliferous systems. The evaluation of various inorganic and organic geochemical parameters indicates that the organic matter is primarily of marine origin, deposited in a marine carbonate environment typical of reefal systems, under oxic-to-dysoxic conditions. The low variability in the TOC concentrations and in the distributions of the biomarkers extracted from the samples suggests that the paleoenvironmental conditions and the organic-matter supply remained approximately co...

2010-01-01

266

Aromatics oxidation and soot formation in flames. Progress report, August 15, 1993--June 30, 1994  

Energy Technology Data Exchange (ETDEWEB)

This project is concerned with the kinetics and mechanisms of aromatic oxidation and soot and fullerenes formation in flames. The objective of the aromatics oxidation work is to identify and measure the concentration of important intermediates and products in benzene oxidation, and to determine reaction mechanisms and kinetics properties consistent with the behavior seen in flames. The research on soot formation is concerned primarily with the particle inception stages, but the work includes study of soot structure at all stages of growth in order to obtain mechanistic information from evidence of growth steps recorded in the structure of the particles. The ultimate objective is to understand how nascent soot particles are formed from high molecular weight compounds, including the roles of planar and curved PAH and the relationship between soot and fullerenes. The objective of the proposed research on fullerenes is to develop a more ...

1994-10-01

267

Army Transformation to Expeditionary Formations  

Science.gov (United States)

... gap" between the arrival ofquick response forces, such as the 82nd Airborne Division and the ... nd Airborne is just exactly that, light airborne infantry. ...

2011-05-14

268

Ambulatory Care Data Base (ACDB) Data Dictionary ...  

Science.gov (United States)

... DATA ELEMENT NAME MNEZONIC M codes MCODE DATA ELEMENT NUMBER FORMAT RECORD POSITION 34 Char 172-177 6 ...

1989-11-01

269

The greenhouse gases N{sub 2}O, CH{sub 4} and CO{sub 2} in coniferous forest soils as influenced by nitrogen input, acidity, moisture and temperature; Drivhusgassene N{sub 2}O, CH{sub 4} og CO{sub 2} i barskogsjord under paavirking av N-tilfoersel, surhet, fuktighet og temperatur  

Energy Technology Data Exchange (ETDEWEB)

The thesis relates to an investigation done on greenhouse gases in coniferous forest soils. The production of nitrous oxide (N{sub 2}O) and carbon dioxide (CO{sub 2}), and the consumption of methane (CH{sub 4}) in a temperate forest soil were studied by a rapid and sensitive gas chromatographic (GC) method for analysing all three greenhouse gases at or below ambient levels. Gas fluxes were measured in soil incubation and lysimeter experiments. 15 soil samples were taken at random within a 100 m{sup 2} area in a Norway spruce forest stand (Picea abies). The fluxes of N{sub 2}O, CH{sub 4} and CO{sub 2} were measured under standardized laboratory incubation conditions to investigate spatial variability in relation to other factors such as nitrogen (N) mineralization rate, nitrification rate, organic carbon (OC), total N and pH. The effects of temperature, soil moisture content, and ammonium addition were also studied in an incubation experiment. A more detailed study ...

1994-07-01

270

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

271

Sanitation of the River Lahn concerning organic loads from waste water. Pt. 2. The impact of effluents from waste water treatment plants; Sanierung der Abwasserbelastung eines Fliessgewaessers am Beispiel der Lahn. T. 2. Klaeranlagenemissionen  

Energy Technology Data Exchange (ETDEWEB)

In a case study of the River Lahn, Hessen, Germany, the ecological impact of effluents from sewage treatment plants was investigated. These emissions have a significant impact on the receiving water quality with ammonia, nitrite, phosphorus and the eutrophication as most important factors. Current legislation standards seem to be sufficent for the sanitation of the nitrogen load. The potential of phosphorus removal in sewage treatment plants however may not reach the demand for eutrophication abatement. Therefore, integrated and immission oriented strategies are required including in site measures of river restoration. (orig.) [Deutsch] An der hessischen Lahn wurde in einem mehrjaehrigen Forschungsvorhabens die Bedeutung von Abwasserereinleitungen aus Klaeranlagen hinsichtlich ihrer gewaesseroekologischen Relevanz untersucht. Wesentliche Belastungen beziehen sich auf die Parameter Ammonium, Nitrit und Phosphor sowie eutrophierungsbedingte Folgeerscheinungen. ...

1995-12-01

272

Responses of aquatic organisms to metal pollution in a lowland river in Flanders: A comparison of diatoms and macroinvertebrates  

International Nuclear Information System (INIS)

The role of macroinvertebrates and diatoms as indicator for metal pollution was investigated by assessing both biota along a metal gradient in the Belgian river the Dommel. Macroinvertebrates and diatoms were sampled in summer and winter and physical-chemical characteristics of the water were measured at four different sample periods and related to sediment characteristics. Although metal concentrations, except cadmium, in the water nowhere exceeded water quality standards, high metal concentrations were measured in the sediment, indicating historical contamination of the Dommel. At the sites that were situated downstream of the pollution source, high levels of conductivity and chloride were measured in the water. Redundancy Analysis (RDA) indicated pH, phosphate and zinc as the significant environmental variables explaining each respectively 7.7%, 11.6% and 22.6% of the macroinvertebrate community composition. Two clusters could be separated, with Gammarus pulex, Leptocerus ...

2008-12-15

273

Production of yellow cake from rock phosphate deposits and its characterization  

International Nuclear Information System (INIS)

This study was carried out mainly to produce uranium trioxide (UO_3), with the standard of commercial specifications from rock phosphate deposits in eastern part of Nuba mountains, south Kurdufan state. A simplified hydrometallurgical procedure has been adopted for production of yellow cake from the ore. Elemental analysis has shown that the ore is rich in Ca and deficient in elements of potential interest such as Fe, Cu and Zn. Uranium content in ore, phosphoric acid and purified yellow cake (UO_3) obtained with different precipitants was analyzed using alpha-spectrometry. On the average, the activity concentration of uranium in ore corresponds to 82 #+-# 24 ppm (0.10%). From the data of pregnant liquor, it was observed that the addition of KCIO_3 as an oxidant improves the dissolution of uranium from the ore by almost 20%. Data has also indicated that the yellow cake purified by hydrogen peroxide has higher concentration of uranium by 44.5% over the one purified by TBP extraction. ...

2002-01-01

274

Phase 2 report on the evaluation of polyacrylonitrile (PAN) as a binding polymer for absorbers used to treat liquid radioactive wastes  

Energy Technology Data Exchange (ETDEWEB)

The performance of PAN-based composite absorbers was evaluated in dynamic experiments at flow rates ranging from 25--100 bed volumes (BV) per hour. Composite absorbers with active components of ammonium molybdophosphate (AMP) PAN and K-Co ferrocyanide (KCoFC) PAN were used for separating Cs from a 1 M HNO{sub 3} + 1 M NaNO{sub 3} + 2 {times} 10{sup {minus}5} M CsCl acidic simulant solution. KCoFC-PAN and two other FC-based composite absorbers were tested for separating Cs from alkaline simulant solutions containing 0.01 M to 1 M NaOH and 1 M NaNO{sub 3} + x {times} 10{sup {minus}4} M CsCl. The efficiency of the Cs sorption on the AMP-PAN absorber from acidic simulant solutions was negatively influenced by the dissolution of the AMP active component. At flow rates of 50 BV/hr, the decontamination factor of about 10{sup 3} could be maintained for treatment of 380 BV of the feed. With the KCoFC-PAN absorber, the decontamination factor of about 10{sup 3} could be ...

1996-05-01

275

High-affinity lead binding proteins in rat kidney cytosol mediate cell-free nuclear translocation of lead  

Energy Technology Data Exchange (ETDEWEB)

The PbII binding characteristics of the previously reported PbII binding proteins of rat kidney cytosol were investigated further. Saturation and Scatchard analysis of /sup 203/Pb binding in whole cytosol and in 40% saturated ammonium sulfate precipitated fractions disclosed a class of relatively high-affinity sites with an apparent Kd of approximately 50 nM and binding capacities of approximately 41 and 9 pmol/mg of protein, respectively. Two /sup 203/Pb binding proteins with approximate molecular masses of 63K and 11.5K daltons and a high molecular weight component (greater than 200K) were isolated by Sepharose-6B column chromatography. The time course of association of /sup 203/Pb with cytosol and the 63K protein showed maximum binding at 18 hr which was stable up to 25 hr at 4 degrees C. The approximate half-time dissociation rate (T 1/2) of specifically bound /sup 203/Pb to the 63K protein was 100 min at 4 degrees C whereas the 11.5K protein showed little ...

1985-02-01

276

High-affinity lead binding proteins in rat kidney cytosol mediate cell-free nuclear translocation of lead  

International Nuclear Information System (INIS)

The PbII binding characteristics of the previously reported PbII binding proteins of rat kidney cytosol were investigated further. Saturation and Scatchard analysis of "2"0"3Pb binding in whole cytosol and in 40% saturated ammonium sulfate precipitated fractions disclosed a class of relatively high-affinity sites with an apparent Kd of approximately 50 nM and binding capacities of approximately 41 and 9 pmol/mg of protein, respectively. Two "2"0"3Pb binding proteins with approximate molecular masses of 63K and 11.5K daltons and a high molecular weight component (greater than 200K) were isolated by Sepharose-6B column chromatography. The time course of association of "2"0"3Pb with cytosol and the 63K protein showed maximum binding at 18 hr which was stable up to 25 hr at 4 degrees C. The approximate half-time dissociation rate (T 1/2) of specifically bound "2"0"3Pb to the 63K protein was 100 min at 4 degrees C whereas the 11.5K protein showed little dissociation of ...

277

Electrochemical and chemical dissolution behavior of Zn-Fe alloy coatings and its application to the analysis of Zn-Fe alloy layer. Zn-Fe kei mekki so no bunkyokuter dot yokai kyodo to teiryo bunseki eno oyo  

Energy Technology Data Exchange (ETDEWEB)

As surface treated steel sheets, steel sheets with Zn-Fe coatings as well as double-layer steel sheets with Fe-P alloy coatings on Zn-Fe alloy coatings are often used practically. Two treatment methods, which are used to dissolve only alloy layers without dissolving steel sheets in order to find amount and composition of alloy layersr have already been reported. This report investigates the mechanisms of these methods, particularly the mechanisms to control dissolution of steel sheets. In the alkali-dissolution method, Zn-Fe alloy coatings are dissolved in a strong alkaline solution(NaOH-triethanolamine (TEA)-H{sub 2}O{sub 2}). In this case, steel sheets are insoluble because passive films are formed on the surface. In the cathodic polarization electrolysis method, alloy layers are electrolyzed({minus}l.2V) and dissolved in an ammonium nitrate-0-phen electrolyte. At this potential, dissolution of steel sheets can be prevented by the 0-phen films adsorbed on the ...

1991-11-01

278

Effects of chronic NH4Cl dosage and swimming exercise on bone metabolic turnover in rats.  

Science.gov (United States)

To determine the effects of ammonium chloride (NH4Cl) dosage and swimming exercise training during 4 weeks on bone metabolic turnover in rats, seven-week-old female 24 Wister-Kyoto (WKY) rats were investigated by bone status including bone mineral density (BMD) and biomechanical markers from blood and urine. Twenty-four rats (initial weight: 191.2+/-7.6 g) were randomly divided into four groups: baseline (8 weeks old) control group (n=6, BC), 4-week control group (n=6, Con), 4-week swimming exercise loading group (n=6, Swim) and 4-week chronic NH4Cl dosage group (n=6, Acid). All rats were fed an AIN93M diet (Ca: 0.5%, P: 0.3%), and both Con and Swim groups were pair-fed by feeding volume of the NH4Cl dosage group. The acid group only received 0.25 M NH4Cl distilled water ad libitum. At the end of the experimental period, rats were sacrificed with blood drawn and femur and tibia were removed for analysis of bone mineral density (BMD) by dual energy X-ray ...

2005-11-01

279

A sample preparation for quantitative determination of magnesium in individual lymphocytes by electron probe X-ray microanalysis.  

Science.gov (United States)

We present a sample preparation method for measuring magnesium in individual whole lymphocytes by electron probe X-ray microanalysis. We use Burkitt's lymphoma cells in culture as the test sample and compare X-ray microanalysis of individual cells with atomic absorption analysis of pooled cell populations. We determine the magnesium peak-to-local continuum X-ray intensity ratio by electron probe X-ray microanalysis and calculate a mean cell magnesium concentration of 39 +/- 19 mmol/kg dry weight from analysis of 100 cells. We determine a mean cell magnesium concentration of 34 +/- 4 mmol/kg dry weight by atomic absorption analysis of pooled cells in three cell cultures. The mean cell magnesium concentrations determined by the two methods are not significantly different. We find a 10% coefficient of variation for both methods of analysis and a 30% coefficient of variation in magnesium concentration among individual cells by electron probe X-ray microanalysis. We wash cells in ...

1986-01-01

280

A field demonstration of the microbial treatment of sour produced water  

Energy Technology Data Exchange (ETDEWEB)

The potential for detoxification and deodorization of sulfide-laden water (sour water) by microbial treatment was evaluated at a petroleum production site under field conditions. A sulfide-tolerant strain of the chemautotroph and facultative anaerobe, Thiobacillus denitrificans, was introduced into an oil-skimming pit of the Amoco Production Company LACT 10 Unit of the Salt Creek Field, Wyoming. Field-produced water enters this pit from the oil/water separation treatment train at an average flowrate of 5,000 bbl/D (795 m{sup 3}/D) with a potential maximum of 98,000 bbl/D (15,580 m{sup 3}/D). Water conditions at the pit inlet are 4,800 mg/l TDS, 100 mg/l sulfide, pH 7.8, and 107{degrees}F. To this water an aqueous solution of ammonium nitrate and diphosphorous pentoxide was added to provide required nutrients for the bacteria. The first 20% of the pit was aerated to a maximum depth of 5 ft (1.5 m) to facilitate the aerobic oxidation of sulfide. No provisions for pH ...

1995-12-31

281

The formation of counterrotating cores in elliptical galaxies  

International Nuclear Information System (INIS)

The mechanism proposed by Kormendy (1984) for the formation of counterrotating cores in elliptical galaxies is investigated using self-consistent numerical simulations of mergers between a high- and a low-luminosity elliptical galaxies. The conditions for a counterrotation to appear are determined, observational properties of the remnants are described, and the evolution of the structural and kinematic parameters of the larger galaxy is analyzed. It is shown that a counterrotation results only when the merging orbits are retrograde, due to a large change in the secondary spin during the merger. 36 refs.

282

Stability ranges of Li-#alpha#'-sialons  

International Nuclear Information System (INIS)

The formation of #alpha#'-sialon using Li as a modifying cation was investigated. The effects of the Li content, firing temperatures and Si/Al ratios on #alpha#'- yield were studied. The results indicated that at lower sintering temperatures the stabilisation of #alpha#'-sialons was obtained but the high weight losses of Li at higher temperatures limited the stabilisation. Increased ''Al'' content in the compositions resulted in an increase in the stability of Li-#alpha#'-sialon at higher temperatures, by the formation of a liquid phase which retains Li in the system. (orig.).

1993-10-04

283

Silicon electrochemistry related to the formation of porous silicon  

Energy Technology Data Exchange (ETDEWEB)

We have examined in detail the electrochemistry of both n- and p-type single crystal (100) silicon in the porous silicon formation regime using a rotating Si disk apparatus with a Ag/AgCl reference electrode. Our findings impact the use and optimization of buried n- or p-type layer anodization for silicon-on-insulator (SOI) wafer synthesis. Results are briefly discussed. 3 refs.

1988-01-01

284

Radiation doses in adults and children in standardized diagnostic radiology  

International Nuclear Information System (INIS)

For comparison of radiation exposure and risk in different diagnostic procedures for adults and children dose measurements and calculations of organs with special risk were carried out. Parameters of image formation influencing image quality as well as of exposure concerning infants and children are recorded and discussed as to radiation exposure and protection. Conclusions are drawn with respect to systems of image formation and to standards of examination and quality assurance.

1987-01-01

285

Polysulfone/Metal Nanocomposites by Simultaneous Photoinduced Crosslinking and Redox Reaction  

British Library Electronic Table of Contents (United Kingdom)

Abstract A diacrylate polysulfone oligomer is synthesized and used as the acrylic oligomer for the in situ synthesis of noble metal/PSU nanocomposites through UV-induced simultaneous radical polymerization of acrylic functionalities and NP formation by reduction of their precursors. Thus, silver or gold NPs are formed in situ during polymer network formation. FESEM analysis of the morphology of the cured systems demonstrates that the nanoparticles of the noble metals are homogeneously distributed in the network without macroscopic agglomeration.

2011-01-01

286

Physicochemical basis for formation of renal stones of calcium phosphate origin: calculation of the degree of saturation of urine with respect to brushite  

UK PubMed Central (United Kingdom)

Brushite (CaHPO4·2H2O) was considered to govern the formation of renal calculus of calcium phosphate origin. The degree of saturation of urine with respect to this phase...Full Text Available

1969-10-01

287

NO{sub x} formation in lean premixed combustion of methane at high pressures  

Energy Technology Data Exchange (ETDEWEB)

High pressure experiments in a jet-stirred reactor have been performed to study the NO{sub x} formation in lean premixed combustion of methane/air mixtures. The experimental results are compared with numerical predictions using four well known reaction mechanisms and a model which consists of a series of two perfectly stirred reactors and a plug flow reactor. (author) 2 figs., 7 refs.

1999-08-01

288

Modeling Transient Discharge into a Tunnel Drilled in a Heterogeneous Formation  

British Library Electronic Table of Contents (United Kingdom)

Abstract An analytical model is developed to predict transient discharge flow into a tunnel drilled at various speeds through a heterogeneous formation. This model relies on simplifying assumptions commonly enforced in hydrogeologic engineering, and combines the convolution and superposition principles to account for composite sections with arbitrary parametric contrasts. An application to the data monitored during the exploratory drilling of an Alpine tunnel confirms the validity of the approach.

2007-01-01

289

Mechanism of zirconium complexing with biphenyl mono- and biscatecholylazo derivatives  

Energy Technology Data Exchange (ETDEWEB)

The complex formation of zirconium with biphenyl mono- and biscatecholyazo derivatives has been studied spectrophotometrically. The composition of the complexes, form and charge of complex-forming zirconium ions have been established. A procedure is suggested for calculation of molar absorptivities and stability constants for each of the complexes formed simultaneously in the system. Possible complex formation schemes have been studied. The data obtained were used to develop a spectrophotometric method of determining zirconium in the presence of large amounts of copper.

1982-05-01

290

Massive Stars in the Local Group: Star Formation and Stellar Evolution  

CERN Document Server

The galaxies of the Local Group that are currently forming stars can serve as our laboratories for understanding star formation and the evolution of massive stars. In this talk I will summarize what I think we've learned about these topics over the past few decades of research, and briefly mention what I think needs to happen next.

2003-01-01

291

Marker studies of silicide formation, silicon self-diffusion and silicon epitaxy using radioactive silicon and Rutherford backscattering  

International Nuclear Information System (INIS)

Radioactive "3"1Si(Tsub(1/2) = 2.62 h) and Rutherford backscattering were used to study Ni_2Si, Pd_2Si and Pt_2Si formation, silicon self-diffusion in silicides and silicon epitaxy in the Si(100)/Pd_2Si/Si (amorphous) system. (Auth.).

292

Marine cables for high power; Sjoekabel med hoeyere effekt  

Energy Technology Data Exchange (ETDEWEB)

A new type of impregnation jelly can be used instead of traditional oil may reduce the formation of cavities in marine high-voltage direct current cables. This provides a foundation for the development of cables with improved insulation and for higher power. This was a conclusion of the Norwegian ''EFFEKT''-project. Using the jelly reduces the size of the cavities substantially and no discharges seem to occur during formation, growth and collapse of cavities. It is also environmentally friendly, since there is no leakage of oil.

2001-07-01

293

LC-MS analysis in the e-beam and gamma radiolysis of metoprolol tartrate in aqueous solution: Structure elucidation and formation mechanism of radiolytic products  

British Library Electronic Table of Contents (United Kingdom)

E-beam and gamma products from the radiolysis of aqueous solutions of (+-)-metoprolol tartrate, saturated in nitrogen, are analyzed by HPLC with on-line mass and UV detectors. The structures of 10 radiolytic products common to e-beam and gamma irradiations are elucidated by comparing their fragmentation pattern to that of (+-)-metoprolol. Two of the radiolytic products are also metabolites. Different routes for the formation of the radiolytic products are proposed.

2006-01-01

294

Intravenous Formulation of HET0016 for Inhibition of Rat Brain 20-Hydroxyeicosatetraenoic Acid (20-HETE) Formation  

UK PubMed Central (United Kingdom)

N-Hydroxy-N′-(4-n-butyl-2-methylphenyl)formamidine (HET0016) is a potent inhibitor of 20-hydroxyeicosatetraenoic acid (20-HETE) formation by specific cytochrome P450 (CYP) isoforms....Full Text Available

2008-11-01

295

Global effects of interactions on galaxy evolution  

International Nuclear Information System (INIS)

Recent observations of the evolutionary properties of paired and interacting galaxies are reviewed, with special emphasis on their global emission properties and star formation rates. Data at several wavelengths provide strong confirmation of the hypothesis, proposed originally by Larson and Tinsley, that interactions trigger global bursts of star formation in galaxies. The nature and properties of the starbursts, and their overall role in galactic evolution are also discussed.

1990-11-01

296

Formation of iron oxides during mechanical activation in water  

International Nuclear Information System (INIS)

It has been shown that mechanical milling of iron in water results in formation of nanocrystalline magnetite Fe3O4 with an average particle size of 0.6 ?m, saturation magnetization of 77 Am2/kg and coercivity of ?150 A/cm. Along with magnetite, an antiferromagnetic Fe-O phase (?10 wt%), which is an aggregate of small iron-oxygen clusters forms.

2007-05-21

297

Formation of hammer fragments in inelastic collisions of /sup 12/C nuclei at 3. 6 GeV/nucleon with emulsion nuclei  

Energy Technology Data Exchange (ETDEWEB)

The emission of hammer fragments in inelastic collisions of carbon nuclei at 3.6 GeV/nucleon with the nuclei of a photographic emulsion has been studied experimentally. The results show that the formation of these fragments is determined primarily by the extent to which the heavy target nucleus breaks up and does not depend directly on the mass of the incident nucleus.

1980-09-01

298

Formation and stability of astatide-mercury complexes  

International Nuclear Information System (INIS)

The formation of astatide-mercury complexes was investigated in aqueous solutions.The obtained complexes were examined by paper electrophoresis. It was found that Hg(OH)At and Hg(OH)I complexes were formed in neutral solution. The stability constants of the obtained complexes were determined by ion-exchange. The preliminary results indicate that the complex of mercury with astatide is much more stable than similar complexes with iodide. (author)

2006-04-01

299

Factors affecting the development of the pressure differential in Upper Paleozoic gas reservoirs in the Sulige and Yulin areas of the Ordos Basin, China  

Energy Technology Data Exchange (ETDEWEB)

The Sulige gas field and the Yulin gas field are located in the north of the Ordos Basin. Reservoir pressure in the Sulige area is subnormal, whereas reservoirs in the Yulin area have normal hydrostatic pressure. This paper provides an explanation of this difference. The characteristics of reservoir sediment and formation water chemistry in the gas reservoirs of these two areas were analyzed. The results showed that both reservoirs have good sealing ability. Data of numerical simulation showed that tectonic uplift resulted in a great reduction in formation pressure in the northern Ordos Basin during the late Cretaceous period, and the decrease was greater in the Yulin gas field than in the Sulige gas field. However, because the total hydrocarbon-generating intensity of the Sulige area (< 24 x 10{sup 8} m{sup 3}/km{sup 2}) was less than that of the Yulin area (> 32 x 10{sup 8} m{sup 3}/km{sup 2}), the gas supply intensity of the ...

2011-01-01

300

FORMATION PROCESS OF THE CIRCUMSTELLAR DISK: LONG-TERM SIMULATIONS IN THE MAIN ACCRETION PHASE OF STAR FORMATION  

International Nuclear Information System (INIS)

The formation and evolution of the circumstellar disk in unmagnetized molecular clouds is investigated using three-dimensional hydrodynamic simulations from the prestellar core until the end of the main accretion phase. In collapsing cloud cores, the first (adiabatic) core with a size of #approx#>3 AU forms prior to the formation of the protostar. At its formation, the first core has a thick disk-like structure and is mainly supported by the thermal pressure. After the protostar formation, it decreases the thickness gradually and becomes supported by the centrifugal force. We found that the first core is a precursor of the circumstellar disk with a size of >3 AU. This means that unmagnetized protoplanetary disk smaller than <3 AU does not exist. Reflecting the thermodynamics of the collapsing gas, at the protostar formation epoch, the first core (or the circumstellar disk) ...

2010-12-01

301

Ephrin B1 Regulates Bone Marrow Stromal Cell Differentiation and Bone Formation by Influencing TAZ Transactivation via Complex Formation with NHERF1?  

UK PubMed Central (United Kingdom)

Mutations of ephrin B1 in humans result in craniofrontonasal syndrome. Because little is known of the role and mechanism of action of ephrin B1 in bone, we examined the function of osteoblast-produced...Full Text Available

2010-02-01

302

Effect of catalysts and solvents on the direct hydroliquefaction of Turkish lignites  

Energy Technology Data Exchange (ETDEWEB)

This paper reports the effectiveness of solvents on the liquefaction of 11 different Turkish lignites investigated by using tetralin, creosote, and anthracene oils. The highest total conversions were obtained with tetralin. The catalytic effects of CoMo and red mud were compared by using creosote oil as the solvent. It was found that red mud catalyzed mainly the asphaltene formation reaction for the given experimental conditions. The additional of CoMo significantly catalyzed the liquefaction reaction, thus increasing the lignite conversion and oil formation.

1990-01-01

303

Effect of Exogenous Indole-3-Acetic Acid and Indole-3-Butyric Acid on Internal Levels of the Respective Auxins and Their Conjugation with Aspartic Acid during Adventitious Root Formation in Pea Cuttings  

UK PubMed Central (United Kingdom)

The influence of exogenous indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) on the internal levels of these auxins was studied during the first 4 days of adventitious root formation in cuttings...Full Text Available

1991-07-01

304

Drilling fluid/formation interaction at simulated in situ geothermal conditions. Final report  

Energy Technology Data Exchange (ETDEWEB)

Interaction of drilling fluids with a geothermal reservoir formation can result in significant permeability impairment and therefore reduced well productivity. This interaction is studied under simulated in situ geothermal conditions of overburden stress, pore fluid pressure, temperature, and pore fluid chemistry. Permeability impairment of an East Mesa KGRA reservoir material is evaluated as a function of stagnation time, drilling fluid, and temperature. Results indicate that all of these parameters contribute significantly to the magnitude and the reversibility of the impairment.

1980-07-01

305

Assessment of the efficacy of braking radiation beam formation of electron accelerators  

International Nuclear Information System (INIS)

Proceeding from analysis of the influence of parameters of the target-filter system on radiation-physical characteristics of braking radiation, some recommendations were issued for assessment of the forming systems of medical accelerators of electrons. A new criterion - a coefficient of the forming system efficacy - was introduced, characterizing a beam formation tract with relation to a whole set of radiotherapeutic problems.

306

A time-resolved optical study of the avalanche and streamer formation in atmospheric nitrogen  

Energy Technology Data Exchange (ETDEWEB)

This work deals with a time-resolved optical study of the avalanche and streamer formation phases leading to breakdown in atmospheric nitrogen. The authors present the results obtained for nitrogen, from experiments and two-dimensional model simulations. This model is used to obtain a better insight in the relevant mechanisms and processes by a comparison of measurements and simulation data. The trends of externally measured quantities correspond with those predicted by the model.

1996-12-31

307

Radiostrontium clearance and bone formation in response to simulated internal screw fixation  

Energy Technology Data Exchange (ETDEWEB)

Changes in radiostrontium clearance (SrC) and bone formation (tetracycline labeling) were observed in the femurs of skeletally mature dogs following the various operative steps involved in bone screw fixation. Drilling, but not periosteal stripping, produced a small but statistically significant increase in SrC and endosteal bone formation in the distal third of the bone. Strontium clearance values equivalent to those produced by drilling alone were recorded after screw fixation at low or high torque (5 versus 20 inch pounds), as well as by the insertion of loosely fitting stainless steel implants. Bone formation (equals the percentage tetracycline-labeled trabecular bone surfaces) was increased by 30% when SrC values exceeded 3.5 ml/100 g bone/min, and the relationship was linear when SrC values ranged between 1.0 and 7.0 ml/100 g bone/min. The changes in SrC and bone formation one-week after bone ...

1987-06-01

308

Lipid domain formation modulates activities of snake venom phospholipase A(2) enzymes.  

Science.gov (United States)

The goal of the present study is to elucidate the effect of lipid domain formation on activities of Naja naja atra and Bungarus multicinctus phospholipase A(2) (PLA(2)) enzymes. Sphingomyelin inhibited enzymatic activity and membrane-damaging activity of PLA(2) against egg yolk phosphatidylcholine (EYPC), while cholesterol and cholesterol sulfate abrogated the inhibitory effect of sphingomyelin. The ability of cholesterol and cholesterol sulfate to abolish the inhibitory effect of sphingomyelin was closely related to their capacity to induce domain formation in EYPC/sphingomyelin vesicles. Laurdan fluorescence measurement revealed that membrane packing of EYPC/sphingomyelin vesicles was differently affected by cholesterol and cholesterol sulfate. Unlike cholesterol, cholesterol sulfate was unable to promote domain formation in dipalmitoylphosphatidylcholine (DPPC) vesicles. Cholesterol increased but cholesterol sulfate ...

2010-08-10

309

In situ ellipsometric studies of formation kinetics of rare earth metal conversion coatings on magnesium alloy  

International Nuclear Information System (INIS)

In situ spectroscopic ellipsometry was employed to investigate the initial regime of rare earth metal (REM) conversion coatings formation on AZ31 magnesium alloy. Three REM salts solutions, 0.05 mol.dm"-"3 Ce(NO_3)_3, La(NO)_3 and Sm(NO)_3 solutions, were used for REM conversion coatings preparation. By deconvoluting the ellipsometric data, the surface of the fresh well-polished AZ31 magnesium alloy was found to be covered with 15.80 nm thick native (hydr)oxide film; the refractive indices and the thickness of Ce, La and Sm conversion coatings were obtained. The formation kinetics of three REM coatings follows different exponential functions and the coatings exhibit different optical properties. La conversion coating has the largest n values and the lowest k values while Sm conversion coating is just opposite. Moreover, the pH variation of the bulk conversion solutions upon the coatings formation was recorded. It is ...

2008-05-01

310

Greater Green River Basin Production Improvement Project  

Energy Technology Data Exchange (ETDEWEB)

The Greater Green River Basin (GGRB) of Wyoming has produced abundant oil and gas out of multiple reservoirs for over 60 years, and large quantities of gas remain untapped in tight gas sandstone reservoirs. Even though GGRB production has been established in formations from the Paleozoic to the Tertiary, recent activity has focused on several Cretaceous reservoirs. Two of these formations, the Ahnond and the Frontier Formations, have been classified as tight sands and are prolific producers in the GGRB. The formations typically naturally fractured and have been exploited using conventional well technology. In most cases, hydraulic fracture treatments must be performed when completing these wells to to increase gas production rates to economic levels. The objectives of the GGRB production improvement project were to apply the concept of horizontal and directional drilling to the Second Frontier ...

1997-10-01

311

Geology of the lower Yellow Creek area, northwestern Colorado  

Energy Technology Data Exchange (ETDEWEB)

The geology and resources of the lower Yellow Creek area, an area at the northwestern margin of the Piceance Creek basin comprising of four 7.5-minute quadrangles, are described. Subsurface face rocks penetrated by drill holes range in age from Pennsylvania to Cretaceous. Measured sections show the Mancos Shale and the Castlegate Sandstone, Iles Formation, and Williams Fork Formation of the Mesaverde Group of Late Cretaceous age and the Fort Union, Wasatch, Green River, and Uinta formations of Tertiary age. Surficial deposits of Quaternary age include terrace gravels, alluvium, and landslides. Fold axes and faults in the area trend northwesterly. The southern part of the area contains major oil-shale resources. Coal-bearing zones in the Williams Fork and Iles formations contain considerable coal. The coal-resources potential is limited, however, by nonpersistence of the thicker coal beds. Small amounts ...

1990-01-01

312

Formation of methyl formate and other organic species in the warm-up phase of hot molecular cores  

CERN Document Server

Aims: The production of saturated organic molecules in hot cores and corinos is not well understood. The standard approach is to assume that, as temperatures heat up during star formation, methanol and other species evaporate from grain surfaces and undergo a warm gas-phase chemistry at 100 K or greater to produce species such as methyl formate, dimethyl ether, and others. But a series of laboratory results shows that protonated ions, typical precursors to final products in ion-molecule schemes, tend to fragment upon dissociative recombination with electrons rather than just ejecting a hydrogen atom. Moreover, the specific proposed reaction to produce protonated methyl formate is now known not to occur at all. Methods: We utilize a gas-grain chemical network to probe the chemistry of the relatively ignored stage of hot core evolution during which the protostar switches on and the temperature of the surrounding gas and dust ...

2006-01-01

313

Formation kinetics and work function tuning of Pd_2Si fully silicided metal gate  

International Nuclear Information System (INIS)

The formation kinetics of Pd_2Si for fully silicided (FUSI) gate formation and the work function tuning of a Pd_2Si FUSI gate by impurity predoping were investigated. It has been found that the morphology and phase of a formed FUSI layer depend not only on the silicidation annealing temperature but also on the heating ramp-up rate and the presence of impurities. Fast ramp-up annealing was necessary to avoid defect formation, such as voids in the silicide film at the oxide interface, and to obtain a homogeneous silicide film containing only Pd_2Si phase. The most severe effect on the silicidation reaction, that is the increase in defect formation, was brought about by As predoping. The work function of the Pd_2Si FUSI gate was modulated by impurity pileup at the Pd_2Si/SiO_2 interface, as in the case of the NiSi FUSI gate. However, the work function shifted in the opposite direction to that of the NiSi ...

2007-04-01

314

Fault-related-folding structure and reflection seismic sections. Construction of earth model using balanced cross section; Danso ga kaizaisuru shukyoku kozo no keitai to jishin tansa danmen. 1. Balanced cross section wo mochiita chika model no kochiku  

Energy Technology Data Exchange (ETDEWEB)

Pre-stacking depth migration treatment is studied for the estimation of the fold configuration from seismic survey cross sections. The estimation of a velocity structure is necessary for the execution of such treatment, and the utilization of structural-geological knowledge is required for its interpretation. The concept of balanced cross section in relation to the fault-bend fold constructs a stratum structure model under conditions that the deformation during fold and fault formation is a planar strain, that there is no change in volume due to deformation, and that a fold is a parallel fold. In addition to the above geometric and kinetic approach, there is another fold formation process simulation model using a Newtonian fluid for study from the viewpoint of dynamics. This simulation stands on the presumption that the boundary contains a ramp that had been in presence before fold formation and that an incompressible ...

1997-05-27

315

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

316

Temporal response of bone to unloading  

Energy Technology Data Exchange (ETDEWEB)

A model of weightlessness in which the hindlimbs of rats are elevated by their tails at a 40 degrees angle to unload the hindlimbs while maintaining normal weight bearing on the forelimbs has been used to simulate certain conditions of space flight. When we used this model in growing rats, we found that growth in bone weight ceased by 1 week in the hindlimbs and lumbar vertebrae, whereas growth in bone weight in the forelimbs and cervical vertebrae remained unaffected. Within 2 weeks, however, the accretion of bone weight in the hindlimbs and lumbar vertebrae returned to normal despite continued skeletal unloading. Since bone weight in the growing rat is primarily determined by bone formation (bone resorption is modest), we investigated the effects of selective skeletal unloading on bone formation during 2 weeks of hindlimb elevation using radioisotope incorporation (with /sup 45/Ca and (/sup 3/H)proline) and histomorphometry (with tetracycline ...

1986-02-01

317

New oil exploration play in Florida: The upper Fredericksberg Dollar Bay Formation  

Energy Technology Data Exchange (ETDEWEB)

The Fredericksberg of South Florida may have a great oil potential that has been overlooked as a primary target in past decades. Previous exploration in the area has targeted the Lower Cretaceous oil-producing Sunniland Formation lower in the stratigraphic section. The Fredericksberg Dollar Bay Formation has hydrocarbon shows in many wells occurring in limestone biohermal deposits as well as in an upper dolomitic section. The Dollar Bay Formation is part of the Big Cypress Group of the Comanchean Series of the Lower Cretaceous. The Lower Cretaceous lithology is composed of evaporitic-carbonate cycles consisting of anhydrites, dolomites, and limestones. There are also present some calcareous shales, mudstones, salt, lignitic material, and carbonaceous material, especially in the anhydrite and limestone intervals. The limestones are usually micritic, chalky, calcarenitic, sometimes argillaceous, containing skeletal particles ...

1990-09-01

318

High-resolution sequence stratigraphy of Lower-Middle Guadalupian outcrops, western Guadalupe Mountains, Texas and New Mexico  

Energy Technology Data Exchange (ETDEWEB)

The authors describe parts of three third-order depositional sequences and their associated system tracts within seismic-scale outcrops of the Lower-Middle Guadalupian Northwestern shelf-to-Delaware basin transition. These sequences are well exposed along a 20-km dip-oriented transect in the western Guadalupe Mountains, Texas and New Mexico. Systems tracts are defined on the basis of lithofacies distribution, stratal geometry, and bounding (stratal termination) surfaces. These Lower-Middle Guadalupian sequences record (1) carbonate platform retrogradation, basin margin erosion, and sediment starvation followed by platform aggradation and progradation (lower San Andres Formation-Cutoff Formation; transgressive and highstand systems tracts), (2) major basin infill by terrigenous clastics bypassed over the underlying lower San Andres highstand carbonate bank and development of a shelf-margin-restricted carbonate bank and coeval base-of-slope apron ...

1990-05-01

319

ARM AND INTERARM STAR FORMATION IN SPIRAL GALAXIES  

International Nuclear Information System (INIS)

We investigate the relationship between spiral arms and star formation in the grand-design spirals NGC 5194 and NGC 628 and in the flocculent spiral NGC 6946. Filtered maps of near-IR (3.6 #mu#m) emission allow us to identify 'arm regions' that should correspond to regions of stellar mass density enhancements. The two grand-design spirals show a clear two-armed structure, while NGC 6946 is more complex. We examine these arm and interarm regions, looking at maps that trace recent star formation-far-ultraviolet (GALEX NGS) and 24 #mu#m emission (Spitzer SINGS)-and cold gas-CO (HERACLES) and H I (THINGS). We find the star formation tracers and CO more concentrated in the spiral arms than the stellar 3.6 #mu#m flux. If we define the spiral arms as the 25% highest pixels in the filtered 3.6 #mu#m images, we find that the majority (60%) of star formation tracers occur in the interarm regions; this result ...

2010-12-10

320

A study on natural convection heat transfer with crust formation in the corium pool  

International Nuclear Information System (INIS)

Experimental and analytical studies in convection cooling and boiling cooling conditions have been performed on natural convection heat transfer with solidified crust formation in the molten metal pool. The present experimental results on the relationship between the Nusselt number and Rayleigh number in the molten metal pool were compared with existing correlations on Rayleigh-Bebard natural convection in an enclosure. A new correlation on the relationship between the Nusselt number and Rayleigh number in the molten metal pool with crust formation has been developed using the experimental data. The experimental results were verified by the analytical study. The experimental study has shown that the bottom surface temperature of the molten metal layer, in all experiments, is the major influential parameter in the crust formation, due to the natural convection flow. The Nusselt number of the case without a crust ...

321

Wave formation mechanism in magnetic pulse welding  

British Library Electronic Table of Contents (United Kingdom)

Wavy interface morphology is observed in Magnetic Pulse Welding (MPW) similarly to that of the Explosion Welding process (EXW). It is recognized that interfacial waves are formed in a periodic manner and have well defined wavelength and amplitude. The phenomenon of wave formation in EXW has been subjected to extensive investigations in which empirical and numerical models have been published. In the present study, a wave formation mechanism for MPW is presented. This wave-creation mechanism was studied by evaluating the influence of sample geometry on wave morphology using stereoscopic optical microscopy. It was found that interfacial waves are formed in a Kelvin-Helmholtz instability mechanism. Reflected shock waves interact with the welding collision point at the weld interface, where in...

2010-01-01

322

The probability distribution of cluster formation times and implied Einstein Radii  

CERN Document Server

We provide a quantitative assessment of the probability distribution function of the concentration parameter of galaxy clusters. We do so by using the probability distribution function of halo formation times, calculated by means of the excursion set formalism, and a formation redshift-concentration scaling derived from results of N-body simulations. Our results suggest that the observed high concentrations of several clusters are quite unlikely in the standard Lambda CDM cosmological model, but that due to various inherent uncertainties, the statistical range of the predicted distribution may be significantly wider than commonly acknowledged. In addition, the probability distribution function of the Einstein radius of A1689 is evaluated, confirming that the observed value of ~45" +/- 5" is very improbable in the currently favoured cosmological model. If, however, a variance of ~20% in the theoretically predicted value of the virial radius is ...

2008-01-01

323

The anisotropic growth in amorphous materials and the latent track formation induced by energetic ion bombardment  

Energy Technology Data Exchange (ETDEWEB)

The thermal spike model has been successfully applied to track formation by swift heavy ions in insulators. Arguments are given supporting the assumption that the thermal spike mechanism is also valid for the anisotropic growth. The glass transition temperature is used as the main thermal parameter of the amorphous solids. Experimental results on the track formation in {alpha}-quartz and in crystalline Ni{sub 3}B and also on the anisotropic growth in Pyrex and Synsil glasses, in amorphous Pd{sub 80}Si{sub 20}, Ni{sub 3}B and Fe{sub 85}B{sub 15} are discussed. Good agreement is found with the predictions of the thermal spike model. (orig.).

1996-02-01

324

The Formation of the Low-sized High Density Plasma Structures in the Self-maintained Plasma-beam Discharge  

International Nuclear Information System (INIS)

The opportunity of use self-maintained plasma-beam discharge in an extended pulsing plasma diode of low pressure for making powerful sources of the soft X-rays is investigated. Conditions of formation of the self-maintained plasma-beam discharge are determined. The mode of making of dense high-temperature plasma on the basis of stannum ions in the discharge is shown. The stannum ions are used as a working element of a radiation sources at pulsing power of electron beam P?10...100 MW. Results of the examination on formation of the dense (np?1016 cm3), small sizes (le?100 eV in conditions of working material evaporation from the anode are given. The total contribution of energy to the discharge has made W < 20 J.

2006-01-01

325

Sulfonaphtholazoresorcinol as reagent for tungsten  

International Nuclear Information System (INIS)

Interaction of W(6) with sulphonaphtholazoresorcinol (SNAR) in aqueous solution has been studied. Tungsten is determined in the form of sulphonaphtholazoresorcinate by extraction with higher alcohols. The optimum conditions for the formation of a complex of W with SNAR in aqueous solution are as follows: a 10-fold excess of SNAR, concentration of HCl 1-1.5N, ethanol content 5-10 vol.%, time of formation of the complex 30 min. A component ratio for the complex has been established in the case of aqueous solution and extract; molar extinction coefficients are 0.9x10"4 and 1.7x10"4, respectively. The formation constant for the complex being extracted is 2.2x10"2"3. A method has been developed for determination of microgram quantities of W in a vanadium specimen.

1977-01-01

326

Structure formation and the origin of dark energy  

CERN Document Server

Cosmological constant a.k.a. dark energy problem is considered to be one major challenge in modern cosmology. Here we present a model where large scale structure formation causes spatially-flat FRW universe to fragment into numerous `FRW islands' surrounded by vacuum. We show that this mechanism can explain the origin of dark energy as well as the late time cosmic acceleration. This explanation of dark energy does not require any exotic matter source nor an extremely fine-tuned cosmological constant. This explanation is given within classical general relativity and relies on the fact that our universe has been undergoing structure formation since its recent past.

2007-01-01

327

Stability of A-15 compounds in multifilamentary superconducting wires  

International Nuclear Information System (INIS)

With the preeminence of A-15 superconducting multifilamentary wires in magnet technology, it has become important to understand the thermodynamic factors influencing the formation of these compounds under solid-state reaction conditions. The six systems Nb--Sn, Nb--Ga, Nb--Ge, Nb--Al, V--Si, and V--Ga were prepared as single filament bronze wires and heat treated in an attempt to precipitate the appropriate A-15 compound. The compounds observed to form were categorized using a formation temperature ratio (stability index) based on the melting temperatures of the constituents which make up the single filament composites. This study has led to several predictions regarding the formation of A-15 compounds using a solid-state bronze diffusion technique. The results of experimentation based on these predictions are presented.

328

Slip and fatigue crack formation processes in an #alpha#/#beta# titanium alloy in relation to crystallographic texture on different scales  

International Nuclear Information System (INIS)

The purpose of this experimental study is to investigate the micromechanical fatigue behavior, in terms of slip nature and preferential cracking sites, of a commercial #alpha#/#beta#-forged Ti-6Al-4V alloy. Electron backscattering diffraction is extensively used to identify the deformation (prismatic, basal, pyramidal slip) and crack formation modes activated by fatigue at the surface of several hundred primary #alpha# nodules. Some fatal crack formation sites are also characterized. Cracking in basal planes is identified as the most critical damage mode leading to fracture. An explanation is proposed which involves the resolved shear stress, taking into account the Schmid factor and the normal stress in relation to the elastic anisotropy of the #alpha#-phase. Finally, the spatial distribution of the secondary cracks is analyzed according to the crystallographic textures (macrozones) present on a mesoscopic scale in the Ti-6Al-4V alloy.

2008-09-01

329

Shallow-lacustrine sand-rich deltaic depositional cycles and sequence stratigraphy of the Upper Triassic Yanchang Formation, Ordos Basin, China  

British Library Electronic Table of Contents (United Kingdom)

ABSTRACT Shallow-lacustrine delta deposits of the Upper Triassic Yanchang Formation form the most important petroleum reservoir sandstone units in the Ordos Basin, China. Recent hydrocarbon exploration and outcrop studies demonstrated that shallow-lacustrine sand-rich deltas developed extensively along the gentle flanks and central part of the basin. The vertical succession of facies indicates that the Yanchang Formation records the entire lacustrine life cycle of the Late Triassic Ordos Basin. Four third-order transgressive-regressive cycles and two larger shallow-lacustrine deltaic cycles have been recognized. A process-based depositional model, derived in part from the modern Ganjiang delta in Poyang Lake, China, is used to infer the origins of the sand-rich lacustrine delta deposits. S...

2010-01-01

330

Selective formation of ZnO nanodots on nanopatterned substrates by metalorganic chemical vapor deposition  

International Nuclear Information System (INIS)

Selective formation of ZnO nanodots was accomplished by metalorganic chemical vapor deposition on nanopatterned SiO_2/Si substrates. Self-organized ZnO nanodots were selectively formed in nanopatterned lines of Si created by etching of SiO_2 with focused ion beam (FIB), whereas any nanodots were hardly observed on the SiO_2 surface in the vicinity of the FIB-sputtered Si areas. The mechanism of the selective formation of ZnO nanodots on FIB-nanopatterned lines is mainly attributed to the effective migration of Zn adatoms diffusing on the SiO_2 surface into the Si lines followed by the nucleation at surface atomic steps and kinks created by Ga"+ ion sputtering. Cathodoluminescence measurements confirmed that the emission originated from the selectively grown ZnO nanodots.

2003-10-27

331

Protoplanetary Disks of Binary Systems in Orion  

CERN Document Server

Dusty primordial disks surrounding young low-mass stars are revealing tracers of stellar and planetary formation. The evolution and lifetime of these disks define the boundary conditions of the mechanisms of planet formation. Stellar companions, however, can significantly change this evolution through their tidal interactions. Stellar evolution and planet formation in binaries have to respond to an environment of truncated, quickly disappearing disks--very different compared to an isolated star environment. In order to investigate details of the influence of binarity on circumstellar disk evolution, we obtained adaptive optics supported near-infrared imaging and spectroscopy of the individual components of 22 low-mass binaries in the well-known Orion Nebula Cluster. Brackett gamma emission, which we detect in several systems, is used as a tracer for the presence of an active accretion disk around each binary component. We ...

2010-01-01

332

Production of titanium alloys with uniform distribution of heat resisting metals  

International Nuclear Information System (INIS)

Consideration is given to the process of the formation of a titanium sponge alloyed with niobium or tantalum, in the joint metallic reduction of titanium, niobium and tantanum chlorides. A percentage composition of the phases observed and the structure of the alloyed sponge have been studied. It is shown that after one remelting operation of the alloyed sponge the alloys of titanium with niobium and tantalum have a uniform component distribution. At the stage of chloride reduction there appear solid solutions based on titanium and an alloying component. The stage of vacuum separation of the reaction mass is associated with a mutual dissolution of the primary phases and the formation of the solid solutions of the alloyed titanium sponge, which, by their composition, are close to the desired alloy composition. The principal features of the formation of a titanium sponge alloyed with niobium and tantalum are in a perfect ...

333

Preparation and characterization of nano hydroxyapatite/polymeric composites materials. Part I  

British Library Electronic Table of Contents (United Kingdom)

The present study is focused on preparation of nano composite materials and the effect of citric acid on their different properties. The formation of nano HA and its interaction with chitosan (C), gelatin (G) polymers and citric acid (CA) materials were studied. The Fourier Transformed Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), transmission electron microscope (TEM), and scanning electron microscope (SEM) were used to characterize these composite materials. The compressive strength (CS) was also measured to know the reinforcement of the prepared composites. The results show that carboxylic and amino groups play crucial role for HA formation on chitosan-gelatin polymeric matrix in the presence of citric acid (CA). The formation of nano HA part...

2011-01-01

334

Pore formation during hybrid laser-tungsten inert gas arc welding of magnesium alloy AZ31B--mechanism and remedy  

International Nuclear Information System (INIS)

One of the major concerns during high speed welding of magnesium alloys is the presence of porosity in the weld metal that can deteriorate mechanical properties. This study seeks to analyze the presence method and quantity of pore during hybrid laser-tungsten inert gas arc (TIG) welding of magnesium alloy AZ31B by radiography, optical microscopy and electron probe microanalysis (EMPA). At the same time, it identifies both the mechanism of pore formation and a remedy for this problem. The experimental results indicate that lacking of shielding gas for laser beam is the dominant cause of macroporosity formation during the hybrid of laser-TIG welding of magnesium Alloys AZ31B plate, and hydrogen is not main cause to form large pores. A favorable weld without porosity can be obtained by appending lateral shielding gas for laser beam.

2005-01-15

335

Ozone generation in a negative corona discharge fed with N_2O and O_2  

International Nuclear Information System (INIS)

Ozone production in a negative corona discharge has been studied experimentally at atmospheric pressure in mixtures of N_2O+O_2 at ambient temperature. Ozone formation was found to be dramatically reduced with increase in the content of N_2O in the mixture. The reaction of O("1D) with nitrous oxide is the most likely process reducing the rate of ozone generation. A considerable decrease in the mean discharge current at a constant voltage was also observed with increasing content of nitrous oxide in the mixture and is attributed to the formation of anions in the discharge. The low values of the calculated mobility of negative charge carriers in the drift region of the discharge is caused by the formation of O"- #centre dot# (N_2O)_n and NO"-#centre dot#(N_2O)_n cluster anions in the drift region of the negative corona discharge.

2004-04-07

336

Origin of water salinity in the coastal Sarafand aquifer (South-Lebanon)  

International Nuclear Information System (INIS)

Author.The geochemical and isotopic study, based on the analysis of twenty water samples from well in the coastal plain of Sarafand (South-Lebanon), permit to eliminate the hypothesis of marine intrusion in this aquifer. The increase of salinity observed in certain wells is due to the contamination of cretaceous aquifer water by the quaternary formations. The two poles of mixing are respectively characterized: by weak tritium contents (between 2 and 3 UT) and a value of stable isotopes (-5,9<0,18<-5,5) corresponding to the appearance of cretaceous formation area; by the high tritium contents and enrichment relative to heavy isotope in the mineralized water of superficial formations. On the other hand, the isotope contents permit the set a rapid renewal of the cretaceous aquifer water due to quick circulation in the Karstic system

337

Oil shale resources of the United States  

Energy Technology Data Exchange (ETDEWEB)

Oil shales of the US represent a tremendous store of potential oil. Most of the deposits are relatively unknown and warrant additional investigation. The summary presented cannot hope to cover all of the deposits. Information about them is usually available only locally. However, the 3 best known deposits - the Green River formation, the Devonian black shales, and the retort member of the Phosphoria formation - represent well over 2 trillion bbl (300 x 10/sup 12/ ton) of potential oil in place. This is an oil resource large enough to supplement quite adequately the US petroleum supply, to extend the time available for realigning our energy supply mixes, and to help reach a satisfactory solution to our current energy dilemma. The concentrated resource in the Green River formation is obviously the next most feasible source of oil. If it cannot be developed, all the other deposits will have to wait until it can be. 100 ...

1980-11-01

338

Microwave sintering of titanium diboride  

Energy Technology Data Exchange (ETDEWEB)

Titanium diboride was heated to high temperatures using microwaves. The highest temperature obtained was 2245/degree/C. Unfortunately, oxidation was a problem, especially at the higher temperatures, although an argon flush and a carbon getter were used. To completely stop oxidation, the oxygen potential must be below 10/sup /minus/18/ atmospheres. Using an argon flush and a carbon getter, titanium diboride was successfully densified to 82% of theoretical without measurable oxidation by heating with microwaves to 1860/degree/C. Density actually decreased upon reaching temperatures above 1860/degree/C due to void formation adjacent to the surface. Void formation is thought to be due to the formation of B/sub 2/O/sub 3/(g) which evolves rapidly above 1860/degree/C because of the loss of a TiO/sub 2/ protective film which melts at this temperature. 9 refs., 12 figs., 2 tabs.

1989-01-01

339

Mechanical-activation-assisted combustion synthesis of #alpha#-SiAlON in air  

International Nuclear Information System (INIS)

With the assistance of mechanical activation, yttrium-stabilized #alpha#-SiAlON was prepared by combustion synthesis in air, instead of high-pressure N_2 atmosphere for the first time. The reaction activity of metallic particles was remarkably enhanced by mechanical activation, which conduced the reduction of grain size, increased the total surface area and formation of fresh surface. The formation of #alpha#-SiAlON by combustion synthesis in air was explained by a kinetically induced reaction mechanism, in which both initial formation of #alpha#-SiAlON and following avoidance of oxidation were fulfilled by the retardation of O_2 infiltration owing to the short reaction period and fast cooling rate.

2007-06-05

340

Lithologic facies, seismic facies, and strike-slip setting of the lower carboniferous alluvial/fluvial/lacustrine Albert formation of New Brunswick. Geoscience report No. 92-2  

Energy Technology Data Exchange (ETDEWEB)

In the early 1980s, a program was begun to evaluate the oil shale resources of the Albert Formation by undertaking a geological lithofacies study of the Albert strata in the Moncton Subbasin of southeastern New Brunswick. Most rock exposures of the Albert were examined from 1982-84 and additional field work was carried out in the summers of 1989 and 1990. In January 1989, 1,900 km of Vibroseis seismic reflection profiles shot from 1981-84 by Chevron Canada Resources Ltd. in the Moncton and Sackville subbasins became publicly available. This report gives the results of the geological investigations on the Albert Formation in the southeastern Moncton Subbasin and the integration of interpreted seismic reflection profiles to help resolve some of the geological problems encountered.

1992-01-01

341

Ionizing feedback from massive stars in massive clusters: fake bubbles and untriggered star formation  

British Library Electronic Table of Contents (United Kingdom)

Abstract We use Smoothed Particle Hydrodynamics to simulate the formation of a massive (106-M-) stellar cluster system formed from the gravitational collapse of a turbulent molecular cloud. We investigate the hierarchical clustering properties of our model system and we study the influence of the photoionizing radiation produced by the system's multiple O-type stars on the evolution of the protocluster. We find that dense gas near the ionizing sources prevents the radiation from eroding the filaments in which most of the star formation occurs and that instead, ionized gas fills pre-existing voids and bubbles originally created by the turbulent velocity field.

2011-01-01

342

In situ strain measurements during the formation of palladium silicide films  

Energy Technology Data Exchange (ETDEWEB)

The evolution of strain in the Pd-Si system during the growth of Pd{sub 2}Si thin films on Si (100) substrate has been followed in situ using a double optical beam technique. As was observed for the Pt-Si system, the reaction to form Pd{sub 2}Si yields a compressive intrinsic surface film stress as well as for the silicon-rich suicides as proposed by Angilello et al. [Thin Film Interfaces and Interactions, edited by J. Baglin and J. Poate (The Electrochemical Society, Pennington, NJ, 1980)]. A transmission electron microscopy analysis has revealed grain growth during the formation of Pd{sub 2}Si which cannot account for the compressive film stresses. The formation of silicide at the interfaces rather than the overall change in volume agrees with the sign of the stresses formed. 29 refs., 4 figs., 3 tabs.

1993-03-01

343

High-resolution sequence stratigraphy and its controls on uranium mineralization. Taking middle Jurassic Qingtujing formation in Chaoshui basin as an example  

International Nuclear Information System (INIS)

By applying the high-resolution sequence stratigraphy, the different sub-divisions of base-level cycles of Qingtujing Formation, Middle Jurassic in Chaoshui Basin are analyzed in detail. 23 short, 3 middle and 1 long base-level cycles are recognized. On the above basis, the corresponding frameworks of high-resolution sequence stratigraphy have been established in northern and southern sub-basins respectively, and the detailed sedimentary facies of MSC_1_-_3 and the special distribution of Qintujing Formation are discussed. It is pointed out that MSC_2 is the most favorable layer for the localization of sandstone-type uranium deposits. (authors)

2006-06-01

344

Graphite as negative electrode in Li-ion batteries; Le graphite comme electrode negative dans les accumulateurs Li-ion  

Energy Technology Data Exchange (ETDEWEB)

The last developments in lithium batteries design have demonstrated the advantages of graphite: competitive cost, flat output curve, high capacity thanks to the obtention of a final compound close to LiC{sub 6}, good behaviour during cycling and a high mass energy. However, these advantages are slightly tarnished by parasite secondary reactions during the evolution of the element. Two different cases are encountered: the formation of a passivation layer (loss of Li ions and formation of irreversible bounds) and the formation of a passivation layer with a reaction between graphite and the solvent (partial destruction of the graphite crystal lattice). In the first case, the theoretical graphite insertion capacity remains at 372 mAh/g while in the second case the insertion capacity is greatly reduced. Abstract only. (J.S.)

1996-12-31

345

Electron-microscopic study of amorphous boron structure  

Energy Technology Data Exchange (ETDEWEB)

Using the method of high resolution electron microscopy (HEM) the shape and structure of powder particles of elementary amorphous boron, prepared by plasmochemical reduction of boron trichloride by hydrogen before and after their heat treatment in vacuum of approximately 1 x 10 SPa at the temperature of approximately 800 deg C for 30 min, have been studied. It is established, that ultradispersed particles of amorphous boron present flat formations (discs) of stable configurations, composed of several icosahedrons (structural elements); their growth during heat treatment takes place first in habitus plane without far order formation, and then, after attaining the diameter of approximately 500 A, the process of three-dimensional crystallization starts, which leads to the formation of crystal lattice of boron US -rhombohedric modification.

1985-05-01

346

Effects of surfaces and leachables on the stability of biopharmaceuticals  

British Library Electronic Table of Contents (United Kingdom)

Abstract Therapeutic proteins are exposed to various potential contact surfaces, particles, and leachables during manufacturing, shipping, storage, and delivery. In this review, we present published examples of interfacial- or leachable-induced aggregation or particle formation, and discuss the mitigation strategies that were successfully utilized. Adsorption to interfaces or interactions with leachables and/or particles in some cases has been reported to cause protein aggregation or particle formation. Identification of the cause(s) of particle formation involving minute amounts of protein over extended periods of time can be challenging. Various formulation strategies such as addition of a nonionic surfactant (e.g., polysorbate) have been demonstrated to effectively mitigate adsorption-i...

2011-01-01

347

Development of Point Arguello field, offshore California  

Energy Technology Data Exchange (ETDEWEB)

Development drilling from Chevron-operated Platform Hermosa, located on OCS-P 0316 of the Point Arguello field, began on January 30, 1987. To date, seven development wells have been drilled in to the northwest-southeast-trending, doubly plunging anticlinal structure. The results from drilling have confirmed the presence of intense folding and fracturing in the targeted Monterey Formation. Over 700 ft of conventional core were recovered from the B-2 well in the lower Sisquoc and Monterey Formations. Analysis of the core material has yielded important information on lithologic variations and fracture patterns in the productive Monterey Formation. Initial results of core studies, DST data, and wireline studies indicate a correlation between rock type and fracturing. Fracture trends and directional permeability suggested by drill-stem testing may affect future drilling patterns in the field.

1988-03-01

348

Description of Cretaceous Sedimentary Sequence of the Yaojia Formation Recovered by CCSD-SK-Is Borehole in Songliao Basin: Lithostratigraphy, Sedimentary Facies and Cyclic Stratigraphy  

British Library Electronic Table of Contents (United Kingdom)

The Yaojia Formation recovered by CCSD-SK-Is borehole (China Cretaceous Continental Scientific Drilling-SongkeI-the south borehole) is 157.67 m long and 99.96% of cores recovery. The age of the formation corresponds with a range from the Santonian to the early Campanian. The sequences and processes of lithology-lithofacies and cyclic stratigraphy are revealed by a detailed core description. Eleven rock types and three kinds of sedimentary subfacies, including shallow lake, deep lake, and delta front, are recognized from the drilling core. There are eleven sedimentary microfacies including dolostone, argillaceous limestone, shallow lake turbidite, deep lake turbidite, subaqueous mouth bar, distal bar, sheet sandstone, subaqueous distributary bay, slump deposits, shallow lake mudstone, and d...

2009-01-01

349

Description of Cretaceous Sedimentary Sequence of the Quantou Formation Recovered by CCSD-SK-Is Borehole in Songliao Basin: Lithostratigraphy, Sedimentary Facies and Cyclic Stratigraphy  

British Library Electronic Table of Contents (United Kingdom)

The Quantou Formation recovered by CCSD-SK-Is borehole (China Cretaceous Continental Scientific Drilling-SongkeI-the south borehole) is 132.07 m long and the recovery of cores is 100%. The sequence and process of lithology-lithofacies and cyclostratigraphy are revealed by a detailed core description. Nine rock types and three kinds of sedimentary facies including meandering river, shallow lake, and delta front are recognized from the drilling core, there are ten sedimentary microfacies, which are point bar, natural levee, crevasse splay, crevasse channel, floodplain, flood lake, distributary mouth bar, interdistributary bay, mudstone of still water, and turbidite. The Quantou Formation represents seventy-six meter-scale cycles (sixth-order cycle), twenty-five fifth-order cycles, eight four...

2009-01-01

350

Description of Cretaceous Sedimentary Sequence of the First Member of the Qingshankou Formation Recovered by CCSD-SK-Is Borehole in Songliao Basin: Lithostratigraphy, Sedimentary Facies, and Cyclic Stratigraphy  

British Library Electronic Table of Contents (United Kingdom)

The first member of the Qingshankou Formation recovered by CCSD-SK-Is borehole (China Cretaceous Continental Scientific Drilling-SongkeI-the south borehole) is 81.41 m long, and the recovery of cores is 100%. The age of the member is approximately Turonian. The sequence and process of lithology-lithofacies and cyclic stratigraphy were revealed by a detailed core description. 6 rock types (mudstone, dolomite, marl, limestone, ostracode limestone, and volcanic ash) comprise the sedimentary strata. Deposition occurred in a deep lake, including 6 sedimentary microfacies: mudstone, sandy turbidite, dolomite, marl, limestone, and volcanic ash microfacies. The first member of the Qingshankou Formation represents 81 meter-scale cycles (sixth-order cycle), 25 fifth-order cycles, 6 fourth-order cycl...

2009-01-01

351

Dependence of ion-induced Pd-silicide formation on nuclear energy deposition density  

Energy Technology Data Exchange (ETDEWEB)

Pd/sub 2/Si formation at the Pd-Si interface induced by irradiation with ions having a wide range of nuclear energy of deposition density has been investigated. It is found that the thickness of the silicide layer formed by irradiation is proportional to the ion fluence for irradiation with ions having low energy-deposition densities, while it is proportional to the square root of the fluence for irradiation with ions having energy-deposition densities. The results indicate that Pd/sub 2/Si formation is reaction limited when the energy-deposition density at the interface is low and is diffusion limited when it is high. The results are compared with the phenomenological theory developed by Horino et al. and it is shown that such a dependence of the limiting processes on the energy depositon density is induced when the diffusion is thermally activated while the reaction at the interface is radiation-enhanced.

1986-05-01

352

Decreased dendritic spine density and abnormal spine morphology in Fyn knockout mice  

British Library Electronic Table of Contents (United Kingdom)

Fyn is a Src-family tyrosine kinase that affects long term potentiation (LTP), synapse formation, and learning and memory. Fyn is also implicated in dendritic spine formation both in vitro and in vivo. However, whether Fyn's regulation of dendritic spine formation is brain-region specific and age-dependent is unknown. In the present study, we systematically examined whether Fyn altered dendritic spine density and morphology in the cortex and hippocampus and if these effects were age-dependent. We found that Fyn knockout mice trended toward a decrease in dendritic spine density in cortical layers II/III, but not in the hippocampus, at 1month of age. Additionally, Fyn knockout mice had significantly decreased dendritic spine density in both the cortex and hippocampus at 3months and 1year, an...

2011-01-01

353

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

354

A two-component Frenkel-Kontorowa model for surface alloy formation  

Energy Technology Data Exchange (ETDEWEB)

It has been shown by recent experiments that bulk immiscible metals (e.g. Ag/Cu, Ag/Co and Au/Ni) can form binary alloys on certain surfaces where the substrate mediates the elastic misfits between the two components, thus relieving the elastic strain in the overlayer. These novel surface alloys exhibit a rich phase structure. We formulate a two-component Frenkel-Kontorova model in one dimension to study surface alloy formation. This model can naturally incorporate dislocation formation that plays a crucial role in determining the actual structure of the system. Using energy minimization calculations we provide a phase diagram in terms of average alloy composition and the energy of mixing. Monte Carlo simulations were also performed to study the structure and interaction of the emerging dislocations.

2003-04-02

355

A DFT study of the reactivity of Cp_2AnMe_2 with pyridine N-oxide: Towards a predicted different reactivity of U/Pu and Np  

International Nuclear Information System (INIS)

A predictive reactivity of Cp_2An(IV)Me_2 (with An = uranium [U], neptunium [Np] and plutonium [Pu]) with pyridine N-oxide has been studied at the theoretical level. The predictive reaction, which consists in the formation of a formaldehyde complex, begins after the initial formation of a cyclo-metalated complex produced by a C-H activation of the pyridine N-oxide. A difference of reactivity between U/Pu and Np has been observed and has been attributed to the presence of a more covalent bond between Np and the carbene group in the transition state of formation of a transient carbene intermediate. (authors)

356

misty somites, a maternal effect gene identified by transposon-mediated insertional mutagenesis in zebrafish that is essential for the somite boundary maintenance  

UK PubMed Central (United Kingdom)

Somite boundary formation is crucial for segmentation of vertebrate somites and vertebrae and skeletal muscle morphogenesis. Previously, we developed a Tol2 transposon-mediated...Full Text Available

2008-04-15

357

Use of synthetic oligoribonucleotides to probe RNA-protein interactions in the MS2 translational operator complex.  

UK PubMed Central (United Kingdom)

Synthetic oligoribonucleotides have been used to probe the interaction of MS2 coat protein with the translational operator of the MS2 replicase gene. We have investigated the possible formation of a...Full Text Available

1990-06-25

358

Unusual Topological Arrangement of Structural Motifs in the Baboon Reovirus Fusion-Associated Small Transmembrane Protein  

UK PubMed Central (United Kingdom)

Select members of the Reoviridae are the only nonenveloped viruses known to induce syncytium formation. The fusogenic orthoreoviruses accomplish cell-cell fusion through a distinct...Full Text Available

2005-05-01

359

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

360

The role of metallothionein IIa in defending lens epithelial cells against cadmium and TBHP induced oxidative stress  

UK PubMed Central (United Kingdom)

PurposeHeavy metals and other forms of oxidative stress have been implicated as key factors in the formation of age-related cataract in humans. Metallothioneins are...Full Text Available

361

The role of Holliday junction resolvases in the repair of spontaneous and induced DNA damage  

UK PubMed Central (United Kingdom)

DNA double-strand breaks (DSBs) and other lesions occur frequently during cell growth and in meiosis. These are often repaired by homologous recombination (HR). HR may result in the formation of DNA...Full Text Available

2011-09-01

362

The protein encoded by the rolB plant oncogene hydrolyses indole glucosides.  

UK PubMed Central (United Kingdom)

The rolB gene of Agrobacterium rhizogenes, whose expression stimulates the formation of roots by transformed plant tissues and other growth alterations in transgenic plants, codes for a beta-glucosidase...Full Text Available

1991-11-01

363

The p14 FAST Protein of Reptilian Reovirus Increases Vesicular Stomatitis Virus Neuropathogenesis?  

UK PubMed Central (United Kingdom)

The fusogenic orthoreoviruses express nonstructural fusion-associated small transmembrane (FAST) proteins that induce cell-cell fusion and syncytium formation. It has been speculated that the FAST proteins...Full Text Available

2009-01-01

364

The neurobiology of social attachment: A comparative approach to behavioral, neuroanatomical, and neurochemical studies*  

UK PubMed Central (United Kingdom)

The formation and maintenance of social bonds in adulthood is an essential component of human health. However studies investigating the underlying neurobiology of such behaviors have been scarce....Full Text Available

2008-11-01

365

The influence of tethered epidermal growth factor on connective tissue progenitor colony formation  

UK PubMed Central (United Kingdom)

Strategies to combine aspirated marrow cells with scaffolds to treat connective tissue defects are gaining increasing clinical attention and use. In situations such as large defects where initial...Full Text Available

2009-09-01

366

The formation mechanism of textured YBa sub 2 Cu sub 3 O sub 7-. delta  

Energy Technology Data Exchange (ETDEWEB)

The formation of textured YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (123) from a liquid phase according to the peritectic reaction Y{sub 2}BaCuO{sub 5} (211) + liquid {yields} 123 was analyzed using real-time analysis techniques of high-temperature X-ray diffraction, high-temperature optical microscopy, and environmental scanning electron microscopy (ESEM). Results were coupled with conventional ''post-mortem'' SEM analysis of processed samples at various stages of microstructural development. Observations of 123 formation and growth from the peritectic melt permit the conclusion that the presence of crystalline 211 primarily acts as a source of yttrium. The slow dissolution of 211 into the yttrium deficient liquid phase is the rate controlled step in the formation and growth of the textured 123, rather that its acting as a nucleation site for 123 grains as has been widely assumed. (orig.).

1992-05-20

367

The effect of deposits on the tubes of a horizontal steam generator on its thermal-hydraulic characteristics  

British Library Electronic Table of Contents (United Kingdom)

Analytical relations are obtained for estimating how the distributions of temperature and heat flux vary along a steam-generating tube and how the steam-generator power output reduces due to formation and accumulation of deposits.

2007-01-01

368

The effect of deposits on the tubes of a horizontal steam generator on its thermal-hydraulic characteristics  

Science.gov (United States)

Analytical relations are obtained for estimating how the distributions of temperature and heat flux vary along a steam-generating tube and how the steam-generator power output reduces due to formation and accumulation of deposits.

2007-12-01

369

The effect of an ?-globulin preparation and of polyribonuclease complexes on humoral antibody formation  

UK PubMed Central (United Kingdom)

The effects of bovine α-globulin (BAG), bovine-ribonuclease serum albumin (BSA-RNase) and polyribonuclease (poly-RNase) complexes on the primary response of rodents to sheep erythrocytes have...Full Text Available

1968-06-01

370

The behaviour of iron in the formation of #beta#'-sialon from a fireclay  

International Nuclear Information System (INIS)

The carbothermal reduction of clay minerals in a nitrogen atmosphere is a well established method for producing #beta#'-sialon. There has been some debate within the literature concerning the role that Fe plays in the formation of the #beta#'-sialon phase. However, most workers accept that Fe is able to either catalyze or promote the formation of #beta#'-sialon although some workers have indicated that the function of the Fe is controlled by gas flow rate and there is evidence that Fe also promotes formation of additional phases. The aim of the present study was to characterize the behaviour of Fe within the #beta#'-sialon synthesis. "5"7Fe Moessbauer spectroscopy was employed for the study because this technique is specific to Fe and does not suffer interference from other elements. Moreover, both the coordination and oxidation state and the relative abundances of the various Fe-containing phases are able to be monitored. ...

371

The Stability and Formation of Native Proteins from Unfolded Monomers Is Increased through Interactions with Unrelated Proteins  

UK PubMed Central (United Kingdom)

The intracellular concentration of protein may be as high as 400 mg per ml; thus it seems inevitable that within the cell, numerous protein-protein contacts are constantly occurring. A basic biochemical...Full Text Available

372

The Herschel revolution: unveiling the morphology of the high mass star formation sites N44 and N63 in the LMC  

CERN Document Server

We study the structure of the medium surrounding sites of high-mass star formation to determine the interrelation between the HII regions and the environment from which they were formed. The density distribution of the surroundings is key in determining how the radiation of the newly formed stars interacts with the surrounds in a way that allows it to be used as a star formation tracer. We present new Herschel/SPIRE 250, 350 and 500 mum data of LHA 120-N44 and LHA 120-N63 in the LMC. We construct average spectral energy distributions (SEDs) for annuli centered on the IR bright part of the star formation sites. The annuli cover ~10-~100 pc. We use a phenomenological dust model to fit these SEDs to derive the dust column densities, characterise the incident radiation field and the abundance of polycyclic aromatic hydrocarbon molecules. We see a factor 5 decrease in the radiation field energy density as a function of radial ...

2010-01-01

373

The Formation of Anthocyanic Vacuolar Inclusions in Arabidopsis thaliana and Implications for the Sequestration of Anthocyanin Pigments  

UK PubMed Central (United Kingdom)

Anthocyanins are flavonoid pigments that accumulate in the large central vacuole of most plants. Inside the vacuole, anthocyanins can be found uniformly distributed or as part of sub-vacuolar pigment...Full Text Available

2010-01-01

374

The Candida albicans Dse1 Protein Is Essential and Plays a Role in Cell Wall Rigidity, Biofilm Formation, and Virulence  

UK PubMed Central (United Kingdom)

The fungal pathogen Candida albicans is one of the leading causative agents of death in immunocompromised individuals. It harbors an arsenal of cell wall anchored factors that are implicated...Full Text Available

2011-01-01

375

Ternary Complex Formation on the Adenovirus Packaging Sequence by the IVa2 and L4 22-Kilodalton Proteins?  

UK PubMed Central (United Kingdom)

Assembly of infectious adenovirus particles requires seven functionally redundant elements at the left end of the genome, termed A repeats, that direct packaging of the DNA. Previous studies revealed...Full Text Available

2007-11-01

376

THE OGIP FORMAT FOR 2-D (IMAGE) POINT SPREAD FUNCTION ... - NASA  

Science.gov (United States)

tial/angular spreading of incident photons from a point source caused by the instrument (de- .... Filter. CDTP0001= 'DATA. ' / Type of calibration. CCNM0001= '2D_PSF ' ... the final resolution of sigma=0.5 arcmin in all energy bands. ...

377

Superconductivity in transition-metal germanium systems  

International Nuclear Information System (INIS)

The variation in the superconducting properties of various binary alloys of transition metal-germanium systems was surveyed by studying sputter deposited samples prepared under various conditions. The primary interest has been to study the formation of the stoichiometric A-15 compounds T_3Ge.

378

Substance P Signaling Contributes to Granuloma Formation in Taenia crassiceps Infection, a Murine Model of Cysticercosis  

UK PubMed Central (United Kingdom)

Cysticercosis is an infection with larval cysts of the cestode Taenia solium. Through pathways that are incompletely understood, dying parasites initiate a granulomatous reaction that,...Full Text Available

2010-01-01

379

Stabilization of ?-catenin induces pancreas tumor formation  

UK PubMed Central (United Kingdom)

Background & Aimsβ-catenin signaling within the canonical Wnt pathway is essential for pancreas development. However, the pathway is normally down-regulated...Full Text Available

2008-10-01

380

Septum Formation in Escherichia coli: Characterization of Septal Structure and the Effects of Antibiotics on Cell Division  

UK PubMed Central (United Kingdom)

Septa can be demonstrated in sections of Escherichia coli strains B and B/r after fixation with acrolein and glutaraldehyde. The septum consists of an ingrowth of the cytoplasmic membrane...Full Text Available

1974-07-01

381

Semi-Analytical Models for the Formation of Disk Galaxies; 1, Constraints from the Tully-Fisher Relation  

CERN Document Server

We present new semi-analytical models for the formation of disk galaxies with the purpose of investigating the origin of the near-infrared Tully-Fisher (TF) relation. The models assume that disks are formed by cooling of the baryons inside dark halos with realistic density profiles, and that the baryons conserve their specific angular momentum. Only gas with densities above the critical density given by Toomre's stability criterion is considered eligible for star formation, and a simple recipe for supernovae feedback is included. We emphasize the importance of extracting the proper luminosity and velocity measures from the models, something that has often been ignored in the past. The observed K-band TF relation has a slope that is steeper than simple predictions based on dynamical arguments suggest. Taking the stability related star formation threshold densities into account steepens the TF relation, decreases its scatter, ...

1999-01-01

382

Secondary structure formation and DNA instability at fragile site FRA16B  

UK PubMed Central (United Kingdom)

Human chromosomal fragile sites are specific loci that are especially susceptible to DNA breakage following conditions of partial replication stress. They often are found in genes involved in tumorigenesis...Full Text Available

2010-05-01

383

Santonian To ?Earliest Campanian (Late Cretaceous) Fungi from the Milk River Formation, Southern Alberta, Canada  

Science.gov (United States)

... its infancy. However, the geological record of many fossil fungi is well established (Elsik, 1996; Kalgutkar and Jansonius, ... 1988). A comprehensive account of the history of fossil fungi, and the impor...

384

Same-sex social behavior in meadow voles: multiple and rapid formation of attachments  

UK PubMed Central (United Kingdom)

Adult meadow voles (Microtus pennsylvanicus) are solitary in the spring–summer reproductive season, but during winter months, females and males are socially tolerant...Full Text Available

2009-04-20

385

STUDY OF SYSTEMS AND COST/PERFORMANCE METHODOLOGIES FOR ...  

Science.gov (United States)

of first unit and learning curve (LC) factor for hardware, ETR, and WTR recurring cost respectively. ...... 105 FORMAT (12,A6,F4.2,6X.F7 0,F6 OF7 0.12. 2012) ...

386

Rapamycin inhibits trypanosome cell growth by preventing TOR complex 2 formation  

UK PubMed Central (United Kingdom)

Target of rapamycin (TOR) kinases control cell growth through two functionally distinct multiprotein complexes. TOR complex 1 (TORC1) controls temporal cell growth and is sensitive to rapamycin, whereas...Full Text Available

2008-09-23

387

Radioprotective Effect of American Ginseng on Human Lymphocytes at 90 Minutes Postirradiation: A Study of 40 Cases  

UK PubMed Central (United Kingdom)

AbstractBackgroundIonizing radiation (IR) initiates intracellular oxidative stress through enhanced formation of reactive oxygen species (ROS) that attack DNA leading...Full Text Available

2010-05-01

388

Purification and properties of adenylyl sulphate:ammonia adenylyltransferase from Chlorella catalysing the formation of adenosine 5?-phosphoramidate from adenosine 5?-phosphosulphate and ammonia  

UK PubMed Central (United Kingdom)

Extracts of Chlorella pyrenoidosa, Euglena gracilis var. bacillaris, spinach, barley, Dictyostelium discoideum and Escherichia coli...Full Text Available

1981-06-01

389

Puncture of a Disc and Application of Nucleus Pulposus Induces Disc Herniation-Like Changes and Osteophytes. An Experimental Study in Rats  

UK PubMed Central (United Kingdom)

It has been observed that puncture of a lumbar disc may induce formation of a nodule on the surface of the disc and osteophytes. It is not known if this is based on the presence of a foreign tissue...Full Text Available

390

PtdIns 3-Kinase Orchestrates Autophagosome Formation in Yeast  

UK PubMed Central (United Kingdom)

Eukaryotic cells can massively transport their own cytoplasmic contents into a lytic compartment, the vacuole/lysosome, for recycling through a conserved system called autophagy. The key process in...Full Text Available

2011-01-01

391

Pseudomonas aeruginosa-Plant Root Interactions. Pathogenicity, Biofilm Formation, and Root Exudation1  

UK PubMed Central (United Kingdom)

Pseudomonas aeruginosa is an opportunistic human pathogen capable of forming a biofilm under physiological conditions that contributes to its persistence despite long-term treatment...Full Text Available

2004-01-01

392

Product toxicity and cometabolic competitive inhibition modeling of chloroform and trichloroethylene transformation by methanotrophic resting cells.  

UK PubMed Central (United Kingdom)

The rate and capacity for chloroform (CF) and trichloroethylene (TCE) transformation by a mixed methanotrophic culture of resting cells (no exogenous energy source) and formate-fed cells were measured....Full Text Available

1991-04-01

393

Phase separation, pore structure, and properties of nanofibrous gelatin scaffolds  

UK PubMed Central (United Kingdom)

The development of three-dimensional (3D) biomimetic scaffolds which provide an optimal environment for cells adhesion, proliferation and differentiation, and guide new tissue formation has...Full Text Available

2009-09-01

394

Pattern formation and traveling waves in myxobacteria: Theory and modeling  

UK PubMed Central (United Kingdom)

Recent experiments have provided new quantitative measurements of the rippling phenomenon in fields of developing myxobacteria cells. These measurements have enabled us to develop a mathematical model...Full Text Available

2001-12-18

395

PROBABILISTIC SYSTEMS MODELING AND COST/PERFORMANCE METHODOLOGIES ...  

Science.gov (United States)

sidered as produced in one period of time for learning curve purposes. A ...... 61 FORMAT (6X,13,3XTARGET DATE 1,13,1X,A6,' NO LATER THAN',F4.0, ...

396

PDS_VERSION_ID = PDS3 /* FILE FORMAT AND LENGTH */ RECORD_TYPE ...  

Science.gov (United States)

KDZ@PEDEL@6RRD>ME0HBF?73 96:IE4K?8814# &=83J46:7A4;/??/D;69>B,F=9>E6L@8A82? ...

397

PAS Domain of the Aer Redox Sensor Requires C-Terminal Residues for Native-Fold Formation and Flavin Adenine Dinucleotide Binding  

UK PubMed Central (United Kingdom)

The Aer protein in Escherichia coli is a membrane-bound, FAD-containing aerotaxis and energy sensor that putatively monitors the redox state of the electron transport system. Binding...Full Text Available

2004-10-01

398

On the ease of predicting the thermodynamic properties of beta-cyclodextrin inclusion complexes  

UK PubMed Central (United Kingdom)

BackgroundIn this study we investigated the predictability of three thermodynamic quantities related to complex formation. As a model system we chose the host-guest complexes of...Full Text Available

399

Naturally occurring double-stranded RNA and immune responses. Effects on plaque-forming cells and antibody formation.  

UK PubMed Central (United Kingdom)

A highly purified preparation of double-stranded RNA, obtained from virus-like particles in Penicillium cultures, was found to affert humoral immune responses in mice differentially depending on its...Full Text Available

1975-03-01

400

National Uranium Resource Evaluation: Lander Quadrangle, Wyoming  

Energy Technology Data Exchange (ETDEWEB)

The Lander Quadrangle, Wyoming, was evaluated to a depth of 1500 m to identify environments and delineate areas that exhibit characteristics favorable for the the occurrence of uranium deposits. The evaluation used criteria established for the National Uranium Resources Evaluation program. The methods of surface investigations included evaluation of aerial radiometric and hydrogeochemical stream-sediment reconnaissance data, verification of some reported uranium occurrences, and general field geology with rock, water, and sediment sampling. The subsurface evaluation was accomplished through the use of 230 various oil-well logs. The results of this investigation identified three environments favorable for sandstone uranium deposits in Eocene fluvial sediments. These environments are within the Battle Spring and upper Fort Union Formations of the northern Great Divide Basin and within the Wind River and the Wagon Bed Formations of the southwest ...

1982-07-01

401

National Uranium Resource Evaluation: Lander Quadrangle, Wyoming  

International Nuclear Information System (INIS)

The Lander Quadrangle, Wyoming, was evaluated to a depth of 1500 m to identify environments and delineate areas that exhibit characteristics favorable for the the occurrence of uranium deposits. The evaluation used criteria established for the National Uranium Resources Evaluation program. The methods of surface investigations included evaluation of aerial radiometric and hydrogeochemical stream-sediment reconnaissance data, verification of some reported uranium occurrences, and general field geology with rock, water, and sediment sampling. The subsurface evaluation was accomplished through the use of 230 various oil-well logs. The results of this investigation identified three environments favorable for sandstone uranium deposits in Eocene fluvial sediments. These environments are within the Battle Spring and upper Fort Union Formations of the northern Great Divide Basin and within the Wind River and the Wagon Bed Formations of the southwest ...

1982-01-01

402

Nasal retention of budesonide and fluticasone in man: Formation of airway mucosal budesonide-esters in vivo  

UK PubMed Central (United Kingdom)

AimsThe efficacy of topical glucocorticosteroids in rhinitis and asthma is likely to depend on drug retention in the airway mucosa. With fluticasone propionate, retention may be...Full Text Available

2001-02-01

403

Myosin II transport, organization, and phosphorylation: evidence for cortical flow/solation-contraction coupling during cytokinesis and cell locomotion.  

UK PubMed Central (United Kingdom)

The mechanism of cytokinesis has been difficult to define because of the short duration and the temporal-spatial dynamics involved in the formation, activation, force production, and disappearance of...Full Text Available

1996-08-01

404

Muscularis mucosae in desmoplastic stroma formation of early invasive rectal adenocarcinoma  

UK PubMed Central (United Kingdom)

The origin of myofibroblasts or myofibroblastic cells in the desmoplastic stroma associated with carcinoma invasion has been controversial. In the early invasive area of a rectal adenocarcinoma reported...Full Text Available

2009-10-21

405

Molecular Architecture of the Centriole Proteome: The Conserved WD40 Domain Protein POC1 Is Required for Centriole Duplication and Length Control  

UK PubMed Central (United Kingdom)

Centrioles are intriguing cylindrical organelles composed of triplet microtubules. Proteomic data suggest that a large number of proteins besides tubulin are necessary for the formation and maintenance...Full Text Available

2009-02-15

406

Model and simulation of heat transfer, magnetite oxidation and NOx formation in a grate-kiln taconite pellet induration furnace  

Energy Technology Data Exchange (ETDEWEB)

A numerical model was developed to simulate the combined effects of heat transfer, magnetite oxidation, and NO{sub x} formation in a grate-kiln furnace for taconite pellet induration. Heat transfer from the flame in the kiln was described by the net radiation method. The shrinking core model was used to account for magnetite oxidation on the grate. A novel approach to oxidation of tumbling pellets in a kiln was derived. The Zeldovich mechanism was used to predict thermal NO generation. Temperature fluctuations in the gas streams were estimated with a clipped Gaussian probability density function. The thermal energy balances and mass balances resulted in coupled systems of first-order differential equations, which were solved numerically. The model is capable of predicting NO production and magnetite oxidation in agreement with observation of plant performance. Although the design of the grate-kiln system is for efficient heat and mass transfer, it may not be the ...

1996-12-31

407

Misregulation of the Kinesin-like Protein Subito Induces Meiotic Spindle Formation in the Absence of Chromosomes and Centrosomes  

UK PubMed Central (United Kingdom)

Bipolar spindles assemble in the absence of centrosomes in the oocytes of many species. In Drosophila melanogaster oocytes, the chromosomes have been proposed to initiate spindle assembly...Full Text Available

2007-09-01

408

Method for inhibiting fouling of petrochemical processing equipment  

Energy Technology Data Exchange (ETDEWEB)

Method for inhibiting the formation of foulants on petrochemical equipment which involves adding to the petrochemical, during processing, a composition comprising a thiodipropionate and either a dialkyl acid phosphate ester or a dialkyl acid phosphite ester.

1980-10-07

409

Metacad programmer's guide  

Energy Technology Data Exchange (ETDEWEB)

Metacad is a collection of routines which creates a randomly accessible data structure from Applicon's APPLE-3D data format and supplies a logical method for manipulation of the data structure by a CAD application program.

1983-05-01

410

Mesenchymal cell re-modeling during mouse secondary palate re-orientation  

UK PubMed Central (United Kingdom)

The formation of mammalian secondary palate requires a series of developmental events such as growth, elevation and fusion. Despite recent advances in the field of palate development, the process...Full Text Available

2010-07-01

411

Membrane nanotubes induced by aqueous phase separation and stabilized by spontaneous curvature  

UK PubMed Central (United Kingdom)

Tubular membrane structures are widespread in eukaryotic cells, but the mechanisms underlying their formation and stability are not well understood. Previous work has focused on tube extrusion from...Full Text Available

2011-03-22

412

Melilite formation in a samarium-stabilized #alpha#-sialon ceramic during postsintering heat treatments  

International Nuclear Information System (INIS)

The formation of the melilite solid solution phase (M'), Sm_2Si_3_-_xAl_xO_3_+_xN_4_-_x, in an #alpha#-sialon sample of overall composition Sm_0_._6Si_9_._2_8Al_2_._6_9O_1_._3_6N_1_4_._7_6, was studied as a function of time in the temperature interval 1,375--1,525 C. The #alpha#-sialon ceramic contained only minor amounts of the 21R sialon polytype and some residual grain-boundary glass before heat treatment. In situ studies by high-temperature X-ray diffraction were combined with postsintering heat treatment followed by quenching. The M'-phase was found to be formed by two different mechanisms: either crystallization of the residual grain-boundary liquid or a direct decomposition of the #alpha#-sialon phase. The liquid crystallized during the first 10--15 min of heat treatment, yielding a rapid M'-phase formation, and further formation of M'-phase continued at a much slower rate, related to the decomposition of ...

413

MARINE INFLUENCE IN THE UPPER ORDOVICIAN JUNIATA FORMATION (POTTERS MILLS, PENNSYLVANIA): IMPLICATIONS FOR THE HISTORY ...  

Science.gov (United States)

... on a transgressive surface; examples from the Silurian Whirlpool Sandstone of southern Ontario, Canada. Journal of Sedimentary ... and C. J. Salas. 1991. The Lower Silurian Whirlpool Sandstone. in Cheel, ...

414

Knockdown of Bicaudal C in Zebrafish (Danio rerio) Causes Cystic Kidneys: A Nonmammalian Model of Polycystic Kidney Disease  

UK PubMed Central (United Kingdom)

Polycystic kidney disease (PKD) is one of the leading causes of end-stage renal disease in humans and is characterized by progressive cyst formation, renal enlargement, and abnormal tubular development....Full Text Available

2010-04-01

415

Kinetics and mechanism of superoxide radical reactions with some biologically important compounds in aqueous solutions. Pulse radiolysis  

International Nuclear Information System (INIS)

Microsecond pulse radiolysis of oxygenated aqueous solutions containing 0.02 mol dm"-"3 sodium formate and 2 mmol dm"-"3 phosphate buffer at pH 7 was used to generate superoxide anion radicals. The influence of some biologically important compounds upon the rate of O_2"."-"b"a"r decay as monitored spectrophotometrically in the range of 245-300 nm. Hematoporphyrin (HP), hemin C (HC), catalase (Cat), cobalt sulfophthalocyanine (CoTSPc) were studied. Among the investigated compounds only Cat was found to show a high catalytic efficiency towards the self-decay of O_2"."-"b"a"r. A red shift of 0_2"."-"b"a"r absorption band and slowing down of its decay were observed to take place by adding HP or CoTSPc to the solutions containing formate ions in excess. This effect is associated with the formation of a transient superoxo-complex. An appearance of an intermediate species with absorption maxima at 350 nm and half-life of about 2 s ...

416

Investigation of #alpha#-sialon formation by high temperature X-ray diffraction  

International Nuclear Information System (INIS)

A technique for following sialon formation in situ by high temperature X-ray diffraction (HT-XRD) was developed. The composition chosen for study was an yttrium #alpha#-sialon with x=0.4. Powder compacts containing silicon nitride, aluminum nitride and yttria powders were pre-sintered at 1350 C and then studied by HT-XRD at temperatures between 1450 and 1580 C and nitrogen pressures of 0.11 MPa. The furnace was made from graphite coated with porous silicon nitride/silicon carbide. The coating prevented silicon carbide formation in the sample up to 1600 C. X-ray diffraction results show the formation of a Y_1_0Al_2Si_3O_1_8N_4 phase at 1350 C, which dissolved to form #alpha#-sialon and other phases at higher temperatures. The amounts of #alpha#-sialon formed are similar to the amounts reported by other authors. An empirical method was used for the calculation of activation energy for the silicon nitride to #alpha#-sialon ...

1993-10-04

417

Intracellular Copper Does Not Catalyze the Formation of Oxidative DNA Damage in Escherichia coli?  

UK PubMed Central (United Kingdom)

Because copper catalyzes the conversion of H2O2 to hydroxyl radicals in vitro, it has been proposed that oxidative DNA damage may be an important component of copper toxicity....Full Text Available

2007-03-01

418

Insulin receptor signaling in the development of neuronal structure and function  

UK PubMed Central (United Kingdom)

Sensory experience plays a crucial role in regulating neuronal shape and in developing synaptic contacts during brain formation. These features are required for a neuron to receive, integrate, and transmit...Full Text Available

419

In silico modeling of the specific inhibitory potential of thiophene-2,3-dihydro-1,5-benzothiazepine against BChE in the formation of ?-amyloid plaques associated with Alzheimer's disease  

UK PubMed Central (United Kingdom)

BackgroundAlzheimer's disease, known to be associated with the gradual loss of memory, is characterized by low concentration of acetylcholine in the hippocampus and cortex part of...Full Text Available

420

Identification of a new gene, molR, essential for utilization of molybdate by Escherichia coli.  

UK PubMed Central (United Kingdom)

A mutation in a new gene, molR, prevented the synthesis in Escherichia coli of molybdoenzymes, including the two formate dehydrogenase isoenzymes, nitrate reductase and trimethylamine-N-oxide reductase....Full Text Available

1990-04-01

421

Identification of a distant cis-regulatory element controlling pharyngeal arch-specific expression of zebrafish gdf6a/radar  

UK PubMed Central (United Kingdom)

Skeletal formation is an essential and intricately regulated part of vertebrate development. Humans and mice deficient in Growth and Differentiation Factor 6 (Gdf6) have numerous...Full Text Available

2010-04-01

422

Identification and mobilization by cointegrate formation of a nodulation plasmid in Rhizobium trifolii.  

UK PubMed Central (United Kingdom)

A nodulation plasmid, pRtr-514a, of molecular size 180 megadaltons (Mdal) was identified in Rhizobium trifolii strain NZP514. This plasmid was absent in both spontaneous and heat-cured Nod- derivatives...Full Text Available

1982-07-01

423

Host derived inflammatory phospholipids regulate rahU (PA0122) Gene, Protein, and Biofilm Formation in Pseudomonas aeruginosa  

British Library Electronic Table of Contents (United Kingdom)

This study describes the role of "inflammatory" oxidized (Ox) phospholipids in regulation of rahU (PA0122) expression and biofilm formation in Pseudomonas aeruginosa (383) wild type (rahU+) and rahU mutant (rahU-) strains. Functional analysis of RahU protein from P. aeruginosa in presence of Ox-phospholipids show: (a) LysoPC modulates RahU gene/and protein expression in rahU+ cells; (b) rahU promoter activity is increased by lysoPC and inhibited by PAPC, Ox-PAPC and arachidonic acid; the latter inhibitory effect can be reversed by lysoPC, which was enzymatically derived from PAPC; (c) biofilm formation increased in rahU- cells as compared to rahU+; and (d) inhibition of rahU promoter activity by PAPC and AA (but not lysoPC) showed significantly augmented biofilm formation in rahU+ but not ...

2011-01-01

424

Horizontal liquid film mist two-phase flow, 2. Droplet deposition and entrainment rates  

Energy Technology Data Exchange (ETDEWEB)

In the region of annular liquid film-mist flow, the behavior of the droplets formed from the liquid film and the rate of formation are the subjects to be clarified in connection with the forecast of dry-out point, which becomes a problem in the region of high dryness such as reactor cooling system and steam generators. Many researches have been performed on such problem in vertical tubes, but the characteristics in horizontal flow have not yet been sufficiently clarified. This series of research is to clarify various characteristics, such as the velocity of vapor phase, the flow rate distribution of droplets, the formation and adhesion of droplets and the structure of liquid film, in the region of liquid film-mist flow, where liquid film exists on the bottom of a horizontal rectangular channel, and vapor flow is accompanied by droplets. In this study, by the measurement of the flow rate distribution of droplets on respective cross sections ...

1984-06-01

425

Horizontal liquid film mist two-phase flow, 2  

International Nuclear Information System (INIS)

In the region of annular liquid film-mist flow, the behavior of the droplets formed from the liquid film and the rate of formation are the subjects to be clarified in connection with the forecast of dry-out point, which becomes a problem in the region of high dryness such as reactor cooling system and steam generators. Many researches have been performed on such problem in vertical tubes, but the characteristics in horizontal flow have not yet been sufficiently clarified. This series of research is to clarify various characteristics, such as the velocity of vapor phase, the flow rate distribution of droplets, the formation and adhesion of droplets and the structure of liquid film, in the region of liquid film-mist flow, where liquid film exists on the bottom of a horizontal rectangular channel, and vapor flow is accompanied by droplets. In this study, by the measurement of the flow rate distribution of droplets on respective cross sections ...

1984-01-01

426

Honing the Dagger: The formation of a Standing Joint Special Operations Task Force Headquarters.  

Science.gov (United States)

This monograph explores an alternative way of providing a JSOTF headquarters to the Joint Force Commander. Beginning with a history of joint SOF doctrine, the monograph outlines the evolution of special operations command and control and the subsequent ne...

2005-01-01

427

High-resolution sequence stratigraphic character and sandstone-type uranium ore formation. A case from Saihan Formation in Baiyinwula area, Erlian Basin  

International Nuclear Information System (INIS)

High-resolution sequence stratigraphy has been applied widely in the petroleum exploration and development, many achievements have been achieved. However, it is in the beginning stage that high-resolution sequence stratigraphy is applied to explore the sandstone-type uranium deposits in Erlian Basin. By applying principles of high-resolution sequence stratigraphy and taking typical boreholes as an example, sedimentary cycles of Saihan Formation, the ore-bearing formation in Baiyinwula area are divided and correlated through cross sections. One long-term cycle (LSC_1), two middle-term cycles (MSC_1, MSC_2) have been identified in this study. Based on this and combined with the mineralization character of sandstone uranium deposits in this area, it is presented that the interlayer oxidation zone is developed mainly in the rising hemicycle of MSC_1 and uranium ore bodies predominantly in channel sand bodies that were developed in the system tract ...

2006-12-01

428

High-resolution infrared observations in IC 5146  

Energy Technology Data Exchange (ETDEWEB)

High-resolution near-infrared and far-infrared observations are presented of the southeastern molecular cloud fragment in the IC 5146 dark cloud. These observations rule out earlier suggestions for the formation of massive stars in this fragment.

1984-04-01

429

Heterogeneity of the supramammillary-hippocampal pathways: Evidence for a unique GABAergic neurotransmitter phenotype and regional differences  

UK PubMed Central (United Kingdom)

The supramammillary nucleus (SuM) provides substantial projections to the hippocampal formation. This hypothalamic structure is involved in the regulation of hippocampal theta rhythm and therefore...Full Text Available

2010-09-01

430

H_2 emission arises outside photodissociation regions in ultra-luminous infrared galaxies  

CERN Document Server

Ultra-luminous infrared galaxies are among the most luminous objects in the local universe and are thought to be powered by intense star formation. It has been shown that in these objects the rotational spectral lines of molecular hydrogen observed at mid-infrared wavelengths are not affected by dust obscuration, leaving unresolved the source of excitation of this emission. Here I report an analysis of archival Spitzer Space Telescope data on ultra-luminous infrared galaxies and demonstrate that star formation regions are buried inside optically thick clouds of gas and dust, so that dust obscuration affects star-formation indicators but not molecular hydrogen. I thereby establish that the emission of H_2 is not co-spatial with the buried starburst activity and originates outside the obscured regions. This is rather surprising in light of the standard view that H_2 emission is directly associated with ...

2010-01-01

431

Further investigation of the structure and properties of austenitic stainless steel after plasma nitriding  

Energy Technology Data Exchange (ETDEWEB)

A series of plasma nitriding experiments has been conducted on AISI 304L austenitic stainless steel at temperatures ranging from 375 to 475 C using pulsed-DC plasma with different pulse duty cycles, N{sub 2}-H{sub 2} gas mixtures and treatment times. It is shown that a wide range of treatment parameters exist that allow the formation of the S-phase. The formation and growth of this surface layer depend strongly on the treatment parameters, such as nitrogen partial pressure and duty cycle. Within the parameter range investigated, the layer growth appears to be diffusion controlled with an activation energy about 107 kJ/mol. The formation of CrN precipitates during plasma nitriding is not accompanied by the formation of bcc iron, which might be expected due to the loss of free chromium. However, the S-phase transforms into CrN and bcc iron following a heat treatment at 450 C or higher for 25 h. The wear ...

1999-09-01

432

Free radical mediated cell toxicity by redox cycling chemicals.  

UK PubMed Central (United Kingdom)

Free radical formation has been implicated in the toxicity of a wide range of xenobiotics. In recent years, particular interest has been paid to compounds which can undergo a one electron reduction...Full Text Available

1987-06-01

433

Formation, Repair, and Genotoxic Properties of Bulky DNA Adducts Formed from Tobacco-Specific Nitrosamines  

UK PubMed Central (United Kingdom)

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N′-nitrosonornicotine (NNN) are tobacco-specific nitrosamines present in tobacco products and smoke. Both compounds...Full Text Available

434

Formation of the electret state of polymers in a gas discharge plasma  

Science.gov (United States)

The present article studies the electret state of polymers when moving through an alternating-current corona discharge plasma and investigates means for the determination of the transition of the polymeric material from the initial state of the electret when the corona-displaying voltage is increased.

1983-02-01

435

Formation and fate of gaseous and particulate mutagens and carcinogens in real and simulated atmospheres.  

UK PubMed Central (United Kingdom)

The growing use of coal for heating and electric power generation and diesel engines in light duty motor vehicles will increase not only the existing atmospheric concentrations of criteria pollutants...Full Text Available

1983-01-01

436

Formation and dynamical evolution of galaxies and of their components  

CERN Document Server

From this vast subject, I will pick out and review three specific topics, namely the formation and evolution of bars, the formation of bulges, and the evolution during multiple major mergers. Bars form naturally in galactic discs. Their evolution is driven by the exchange of angular momentum within the galaxy. This is emitted mainly by near-resonant material in the inner disc (bar), and is absorbed by near-resonant material in the outer disc and in the halo. As a result of this, the bar becomes stronger and rotates slower. Bulges are not a homogeneous class of objects. Based on their formation history, one can distinguish three types. Classical bulges are mainly formed before the actual disc component, from collapses or mergers and the corresponding dissipative processes. Boxy/peanut bulges are parts of bars seen edge-on. Finally, disc-like bulges are formed by the inflow of material to the center due to bar torques. Major ...

2005-01-01

437

Formation Energies of Antiphase Boundaries in GaAs and GaP: An ab Initio Study  

UK PubMed Central (United Kingdom)

Electronic and structural properties of antiphase boundaries in group III-V semiconductor compounds have been receiving increased attention due to the potential to integration of optically-active III-V...Full Text Available

438

Exploration petrology of Sunoco Felda trend of south Florida  

Energy Technology Data Exchange (ETDEWEB)

The Sunoco Felda oil trend of the South Florida basin has been a prolific oil producer. All the oil is produced from the Cretaceous Sunniland formation, a leached limestone bioherm. Although the producing section has been considered reefal in the literature, petrographic and biostratigraphic analyses of various cores in producing fields have determined that these deposits are composed of particles of fragmented rudist and other fauna deposited in a tidal shoal. Atop this debris an algae and gastropod section has been deposited, typical of a mound deposited on a tidal mud flat. This model is exemplified in the Sunoco Felda and West Sunoco fields and was used in exploring the Sunoco Felda trend. From the petrological analysis of these two fields and from knowledge of other wells in the basin, biostratigraphic and lithologic trends can be determined and extended offshore into the eastern Gulf of Mexico. The author stresses petrology in exploring the Sunniland ...

1986-09-01

439

Exit from the Golgi Is Required for the Expansion of the Autophagosomal Phagophore in Yeast Saccharomyces cerevisiae  

UK PubMed Central (United Kingdom)

The delivery of proteins and organelles to the vacuole by autophagy involves membrane rearrangements that result in the formation of large vesicles called autophagosomes. The mechanism underlying autophagosome...Full Text Available

2010-07-01

440

Evidence of FCC titanium hydride formation in #beta# titanium alloy: An X-ray diffraction study  

International Nuclear Information System (INIS)

Three types of titanium hydrides have been reported: #delta#, #epsilon# and #gamma# hydrides. The #delta# hydride forms in the composition range from TiH/sub 1.5/ to TiH/sub 1.99/ and has a CaF/sub 2/ structure with metal atoms on an fcc lattice and hydrogen atoms randomly occupying tetrahedral interstitial sites. At higher hydrogen concentrations, TiH/sub 2/, the fct (c/a # #epsilon# transformation is apparently diffusionless, similar to that operating in the cubic/tetragonal transformation in zirconium hydride. The metastable fct #gamma# hydride having a c/a value of 1.09 or 1.12 forms from solid solutions of hydrogen in the hcp #alpha# matrix. While the titanium hydride precipitation in #alpha#-Ti and its alloys has attracted extensive investigation, hydride formation in bcc #beta#-Ti alloys has rarely been studied because they have not been thought to be liable to hydride formation. This paper shows conclusive evidence for the fcc #delta# ...

441

Evaluation of the Curve-fitting method and the Horner-plot method for estimation of the true formation temperature using temperature recovery logging data  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the method to estimate the true formation temperature using temperature recovery logging data after the well reach to total depth (T.D.). The method designated as ''Curve-fitting method (CFM)'' is based on mathematical model proposed by Middleton (1979, 1982). The accuracy and applicability of this method are evaluated with several field data and compared advantageously with the Horner-plot method. Then, real-time data acquisition system including interpretation software has also been successfully developed. As a conclusion, the followings are confirmed: (1) The developed CFM can be applicable to the estimation of the true formation temperature even using 24 hours temperature recovery data, although the Horner-plot method might need up to 120 hours recovery data, usually. (2) Though depending upon the quality of the data and/or number of the temperature recovery logging data, it might be ...

1995-01-26

442

Etudes Fractographiques De Fontes GS Traitees Par Trempe ...  

Science.gov (United States)

... que celle precedemment decrite, dont la formation peut etre causee par une trempabilite inadequate, un temps de maintien isotherme trop court ou ...

1987-01-01

443

Establishment of trophectoderm and inner cell mass lineages in the mouse embryo  

UK PubMed Central (United Kingdom)

The first cell lineage specification in mouse embryo development is the formation of trophectoderm (TE) and inner cell mass (ICM) of the blastocyst. This article is to review and discuss the...Full Text Available

2009-11-01

444

EphB Receptors Couple Dendritic Filopodia Motility to Synapse Formation  

UK PubMed Central (United Kingdom)

SUMMARYMotile dendritic filopodial processes are thought to be precursors of spine synapses, but how motility relates to cell-surface cues required for axon-dendrite recognition...Full Text Available

2008-07-10

445

Effects of extracts from Italian medicinal plants on planktonic growth, biofilm formation and adherence of methicillin-resistant Staphylococcus aureus  

UK PubMed Central (United Kingdom)

One-third of botanical remedies from southern Italy are used to treat skin and soft tissue infection (SSTI). Staphylococcus aureus, a common cause of SSTI, has generated increasing...Full Text Available

2008-08-13

446

Effects of epidermal growth factor on bone formation and resorption in vivo  

Energy Technology Data Exchange (ETDEWEB)

The effects of mouse epidermal growth factor (EGF) on bone formation and resorption were examined in male mice. EGF administration (2-200 ng.g-1.day-1 ip for 7 days) induced a dose-dependent rise in plasma EGF levels that remained within physiological range. Histomorphometric analysis of caudal vertebrae showed that EGF (20 and 200 ng.g-1.day-1) reduced the endosteal matrix and mineral appositional rates after 5 days of treatment as measured by double (3H)proline labeling and double tetracycline labeling, respectively. This effect was transitory and was not observed after 7 days of EGF administration. EGF administered for 7 days induced a dose-dependent increase in the periosteal osteoblastic and tetracycline double-labeled surfaces. At high dosage (200 ng.g-1.day-1) EGF administration increased the osteoclastic surface and the number of acid phosphatase-stained osteoclasts, although plasma calcium remained normal. The results show that EGF administration at ...

1990-02-01

447

Effects of Mo, Cr, and V Additions on Tensile and Charpy Impact Properties of API X80 Pipeline Steels  

Science.gov (United States)

In this study, four API X80 pipeline steels were fabricated by varying Mo, Cr, and V additions, and their microstructures and crystallographic orientations were analyzed to investigate the effects of their alloying compositions on tensile properties and Charpy impact properties. Because additions of Mo and V promoted the formation of fine acicular ferrite (AF) and granular bainite (GB) while prohibiting the formation of coarse GB, they increased the strength and upper-shelf energy (USE) and decreased the energy transition temperature (ETT). The addition of Cr promoted the formation of coarse GB and hard secondary phases, thereby leading to an increased effective grain size, ETT, and strength, and a decreased USE. The addition of V resulted in a higher strength, a higher USE, a smaller effective grain size, and a lower ETT, because it promoted the formation of fine and homogeneous of AF and GB. The steel ...

2009-08-01

448

Earth and Environment: Person detail  

Wastenet

...October 2006 - present: University of Leeds, UK PhD Candidate in Geochemistry Thesis Title: Magnetite formation in reducing natural environments Supervisors: Dr Liane G. Benning ...Germany Bachelor of Science in Geosciences and Astrophysics Project Details Project Title: \\

449

Diabetes Enhances Periodontal Bone Loss through Enhanced Resorption and Diminished Bone Formation  

UK PubMed Central (United Kingdom)

Using a ligature-induced model in type-2 Zucker diabetic fatty (ZDF) rat and normoglycemic littermates, we investigated whether diabetes primarily affects periodontitis by enhancing bone loss...Full Text Available

2006-06-01

450

Determination of principal and impurity components in monocrystals of erbium and yttrium formates grown on the basis of high-pure substances  

International Nuclear Information System (INIS)

Determination of principal and impurity components in monocrystals of erbium and yttrium formates grown on the basis of high-pure formates from oriental primers, using the method of isothermal evaporation of the salt aqueous solutions with pH 4.4 - 4.5, is described. Er and Y were determined complexonometrically by the titration of the complex with arsenazo 1 by EDTA solution, and formate-ion was determined iodometrically. Impurities were analyzed by atomic-absorption and titrimetric methods. The atomic-absorption method permits to determine in the monocrystal from 1 x 10"-"4 to 5 x 10"-"3 % Mg at relative standard deviation S_r = 0.05; from 1 x 10"-"3 to 2.5 x 10"-"2 % Ca at S_r = 0.07 and from 2 x 0"-"4 to 5 x 10"-"3 % Pb ar S_r = 0.08.

451

Determination of heptacaine hydrochloride in solution using nuclear analytical methods  

Energy Technology Data Exchange (ETDEWEB)

The applicability of two nuclear analytical methods: radionuclide X-ray fluorescence analysis and radiometric titrations based on precipitate formations was studied in order to determine the heptacaine hydrochloride in solutions. The applied methods were evaluated based on the obtained sensitivity values.

1984-01-20

452

Determination of heptacaine hydrochloride in solution using nuclear analytical methods  

International Nuclear Information System (INIS)

The applicability of two nuclear analytical methods: radionuclide X-ray fluorescence analysis and radiometric titrations based on precipitate formations was studied in order to determine the heptacaine hydrochloride in solutions. The applied methods were evaluated based on the obtained sensitivity values. (author).

1984-01-01

453

Design of 240,000 orthogonal 25mer DNA barcode probes  

UK PubMed Central (United Kingdom)

DNA barcodes linked to genetic features greatly facilitate screening these features in pooled formats using microarray hybridization, and new tools are needed to design large sets of barcodes to allow...Full Text Available

2009-02-17

454

Deposit formation tendency of lubricants at high temperatures  

Energy Technology Data Exchange (ETDEWEB)

A thin film microoxidation test utilizing the concept of the Lubricant Stability Map has been used to study the effect of temperature on deposit formation by lubricants on upper piston locations of low heat rejection engines. The stability maps were established for two formulated lubricants in this study. These two lubricants were also evaluated in a series of engine tests with various piston temperatures. The deposition phenomena observed in the engine tests have been adequately simulated and described by the stability maps. It is concluded that lubricants at upper piston locations are under a thin film condition similar to that achieved by the thin film microoxidation test. The deposit formation trend is determined by the volatility, thermal stability, and oxidative stability of the base stock. Additives have little effect on deposit formation at very high temperatures. A combined consideration of all competing reaction ...

1995-05-01

455

Demonstration and Evaluation of Magnetic Descalers.  

Science.gov (United States)

Mineral scale formation in water distribution piping impedes flow, resulting in pressure and volume reduction and increasing operational costs. Chemical cleaning is both costly and time consuming, and there are health concerns when chemically cleaning pot...

2001-01-01

456

Cyst Formation in Kidney via B-Raf Signaling in the PKD2 Transgenic Mice*  

UK PubMed Central (United Kingdom)

The pathogenic mechanisms of human autosomal dominant polycystic kidney disease (ADPKD) have been well known to include the mutational inactivation of PKD2. Although haploinsufficiency...Full Text Available

2009-03-13

457

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

458

Critical nucleus size for disease-related polyglutamine aggregation is repeat length dependent  

UK PubMed Central (United Kingdom)

Since polyglutamine (polyQ) aggregate formation has been implicated as playing an important role in expanded CAG repeat diseases, it is important to understand the biophysics underlying the...Full Text Available

2011-03-01

459

Correlation of Byrd and Selborne groups, with implications for the Byrd Glacier discontinuity, central Transantarctic Mountains, Antarctica  

International Nuclear Information System (INIS)

South of Byrd Glacier, central Transantarctic Mountains, Antarctica, Lower Cambrian Shackleton Limestone (Byrd Group) is divided into four informal members. The transition from Shackleton carbonates to clastics of Starshot Formation is conformable, with alternating units of limestone and argillite, and a thick succession of pillow basalt. Douglas Conglomerate is interbedded with and overlies Starshot Formation, and overlies folded Shackleton Limestone unconformably. Lower amphibolite-grade Selborne Group is composed of Madison Marble and Contortion Schist. The contact between the two formations is interbedded marble and schist, and includes metabasalt. We correlate Byrd Group with Selborne Group, Shackleton Limestone with Madison Marble, and Starshot Formation and Douglas Conglomerate with Contortion Schist. These correlations and the lack of equivalent lithologies to the north of Byrd Glacier imply ...

2004-06-01

460

Common Database Format for Network Security Data  

Science.gov (United States)

Page 1. Page 2. Page 3. Page 4. Page 5. Page 6. Page 7. Page 8. Page 9. Page 10. Page 11. Page 12. Page 13. Page 14. Page 15. Page 16. Page ...

1999-07-26

461

Colour television, an imitation of the human visual system.  

UK PubMed Central (United Kingdom)

Colour television is examined as an attempt to imitate the human visual system in image formation, spectral sensitivities, adaptation, contrast effects, signal processing, signal modulation, signal...Full Text Available

1975-07-01

462

Citrate Uptake in Exchange with Intermediates in the Citrate Metabolic Pathway in Lactococcus lactis IL1403?  

UK PubMed Central (United Kingdom)

Carbohydrate/citrate cometabolism in Lactococcus lactis results in the formation of the flavor compound acetoin. Resting cells of strain IL1403(pFL3) rapidly consumed citrate while...Full Text Available

2011-02-01

463

Cell Polarity Regulator PARD6B Is Essential for Trophectoderm Formation in the Preimplantation Mouse Embryo1  

UK PubMed Central (United Kingdom)

In preimplantation mouse development, the first cell lineages to be established are the trophectoderm (TE) and inner cell mass. TE possesses epithelial features, including apical-basal cell polarity...Full Text Available

2010-09-01

464

Catalyst for olefin production  

Energy Technology Data Exchange (ETDEWEB)

A process is claimed for selectively preparing alpha-olefins having from 2 to about 22 carbon atoms by contacting a gaseous mixture containing carbon monoxide and hydrogen with an iron titanate alkali metal hydroxide catalyst at reaction conditions correlated so as to favor the formation of a substantial proportion of such alpha-olefin product.

1981-04-14

465

Carotenoid Crystal Formation in Arabidopsis and Carrot Roots Caused by Increased Phytoene Synthase Protein Levels  

UK PubMed Central (United Kingdom)

BackgroundAs the first pathway-specific enzyme in carotenoid biosynthesis, phytoene synthase (PSY) is a prime regulatory target. This includes a number of biotechnological approaches...Full Text Available

466

Brg1 Is Required for Cdx2-Mediated Repression of Oct4 Expression in Mouse Blastocysts  

UK PubMed Central (United Kingdom)

During blastocyst formation the segregation of the inner cell mass (ICM) and trophectoderm is governed by the mutually antagonistic effects of the transcription factors Oct4 and Cdx2. Evidence indicates...Full Text Available

467

Blood Group A Antigen Is a Coreceptor in Plasmodium falciparum Rosetting  

UK PubMed Central (United Kingdom)

The malaria parasite Plasmodium falciparum utilizes molecules present on the surface of uninfected red blood cells (RBC) for rosette formation, and a dependency on ABO antigens has...Full Text Available

2000-05-01

468

Biodiversity of Costa Rican salamanders: Implications of high levels of genetic differentiation and phylogeographic structure for species formation  

UK PubMed Central (United Kingdom)

Although salamanders are characteristic amphibians in Holarctic temperate habitats, in tropical regions they have diversified evolutionarily only in tropical America. An adaptive radiation centered...Full Text Available

2000-02-15

469

Baryon history and cosmic star formation in non-Gaussian cosmological models: numerical simulations  

British Library Electronic Table of Contents (United Kingdom)

Abstract We present the first numerical,-N-body, hydrodynamical, chemical simulations of cosmic structure formation in the framework of non-Gaussian models. We study the impact of primordial non-Gaussianities on early chemistry (e-, H, H+, H-, He, He+, He++, H2, H+2, D, D+, HD, HeH+), molecular and atomic gas cooling, star formation, metal (C, O, Si, Fe, Mg, S) enrichment, Population-III (popIII) and Population-II-I (popII) transition and on the evolution of -visible- objects. We find that non-Gaussianities can have some consequences on baryonic structure formation at very early epochs, but the subsequent evolution at later times washes out any difference among the various models. When assuming reasonable values for primordial non-Gaussian perturbations, it turns out that they are responsi...

2011-01-01

470

Assay for the enzymatic conversion of indoleacetic acid to 3-methylindole in a ruminal Lactobacillus species.  

UK PubMed Central (United Kingdom)

An assay to measure the rate of enzymatic formation of 3-methylindole (3MI) from indoleacetic acid (IAA) in Lactobacillus sp. strain 11201 was developed. The reaction mixture contained 50 micrograms...Full Text Available

1990-03-01

472

Analysis of the astray/robo2 zebrafish mutant reveals that degenerating tracts do not provide strong guidance cues for regenerating optic axons  

UK PubMed Central (United Kingdom)

During formation of the optic projection in astray/robo2 mutant zebrafish, optic axons exhibit rostro-caudal pathfinding errors, ectopic midline crossing and...Full Text Available

2010-10-13

473

Analysis of semiconductor structures by nuclear and electrical techniques. Final technical report  

Science.gov (United States)

This report summarizes the results obtained under a contract from 1974 to 1977, focusing on silicide formation of thin metal films on a Si substrate. The main thrust of the effort was directed at: (1) Development of the data base on thin-film silicide formation, and the investigation of the influence of the Si substrate on the silicide formation. When taken in context with results of other studies, the data obtained exhibit a clear pattern of behavior among the various metal films, but the detailed picture appears to be complex; (2) Development of marker experiments by ion-implanted Ar or Xe markers; (3) Clarification of the role played by oxygen contamination in silicide formation; (4) Stability of silicide layers; (5) Reaction of metal layers with SiO/sub 2/; (6) Electrical characteristics of Pd/sub 2/Si; and (7) A computer program was written to synthesize backscattering spectra for thin-film samples ...

1978-06-01

474

Analysis of illegitimate genomic integration mediated by zinc-finger nucleases: implications for specificity of targeted gene correction  

UK PubMed Central (United Kingdom)

BackgroundFormation of site specific genomic double strand breaks (DSBs), induced by the expression of a pair of engineered zinc-finger nucleases (ZFNs), dramatically increases the...Full Text Available

475

Ambassade Des Etats-Unis Kinshasa, Congo - Accueil  

Science.gov (United States)

sur la médiatisation des élections Il s'est ouverte le 16 septembre 2011 à Matadi dans le Bas-Congo une formation sur la médiatisation des questions électorales,...

2011-10-13

476

Altering high temperature subterranean formation permeability  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a delayed acrylamide containing polymer crosslinker having stability in an aqueous solution at high temperatures. It comprises: a combination of an aldehyde and a salicylic acid derivative selected from salicylamide and acetysalicylic acid.

1991-02-19

477

A discrete cell model with adaptive signalling for aggregation of Dictyostelium discoideum.  

UK PubMed Central (United Kingdom)

Dictyostelium discoideum (Dd) is a widely studied model system from which fundamental insights into cell movement, chemotaxis, aggregation and pattern formation can be gained. In this system aggregation...Full Text Available

1997-03-29

478

A conserved switch in sensory processing prepares developing neocortex for vision  

UK PubMed Central (United Kingdom)

Developing cortex generates endogenous activity that modulates the formation of functional units, but how this activity is altered to support mature function is poorly understood. Using recordings...Full Text Available

2010-08-12

479

A combined saline formation and gas reservoir CO2 injection pilotin Northern California  

Energy Technology Data Exchange (ETDEWEB)

A geologic sequestration pilot in the Thornton gas field in Northern California, USA involves injection of up to 4000 tons of CO{sub 2} into a stacked gas and saline formation reservoir. Lawrence Berkeley National Laboratory (LBNL) is leading the pilot test in collaboration with Rosetta Resources, Inc. and Calpine Corporation under the auspices of the U.S. Department of Energy and California Energy Commission's WESTCARB, Regional Carbon Sequestration Partnership. The goals of the pilot include: (1) Demonstrate the feasibility of CO{sub 2} storage in saline formations representative of major geologic sinks in California; (2) Test the feasibility of Enhanced Gas Recovery associated with the early stages of a CO{sub 2} storage project in a depleting gas field; (3) Obtain site-specific information to improve capacity estimation, risk assessment, and performance prediction; (4) Demonstrate and test methods for monitoring CO{sub 2} storage ...

2006-04-28

480

A View of NASA's International Cooperation - External Relations - NASA  

Science.gov (United States)

international vehicles, control centers, and ground support personnel. ... consists of thin membranes made from a polymer-based film and ..... (including airplanes and submarines), environmental monitoring, and control ...... sciences can use it to analyze the birth and death of stars, the formation of solar ...

481

A Time-Slotted On-Demand Routing Protocol for Mobile Ad Hoc Unmanned Vehicle Systems  

Energy Technology Data Exchange (ETDEWEB)

The popularity of UAVs has increased dramatically because of their successful deployment in military operations, their ability to preserve human life, and the continual improvements in wireless communication that serves to increase their capabilities. We believe the usefulness of UAVs would be dramatically increased if formation flight were added to the list of capabilities. Currently, sustained formation flight with a cluster of UAVs has only been achieved with two nodes by the Multi-UAV Testbed at the Massachusetts Institute of Technology. (Park, 2004) Formation flight is a complex operation requiring the ability to adjust the flight patterns on the fly and correct for wind gusts, terrain, and differences in node equipment. All of which increases the amount of inner node communication. Since one of the problems with MANET communication is network congestion, we believe a first step towards formation ...

2007-04-01

482

A Patchy Growth via Successive and Simultaneous Cambia: Key to Success of the Most Widespread Mangrove Species Avicennia marina?  

UK PubMed Central (United Kingdom)

Background and AimsSecondary growth via successive cambia has been intriguing researchers for decades. Insight into the mechanism of growth layer formation is, however, limited to...Full Text Available

2008-01-01

483

A Bifunctional Geranyl and Geranylgeranyl Diphosphate Synthase Is Involved in Terpene Oleoresin Formation in Picea abies1[W][OA  

UK PubMed Central (United Kingdom)

The conifer Picea abies (Norway spruce) defends itself against herbivores and pathogens with a terpenoid-based oleoresin composed chiefly of monoterpenes (C10) and diterpenes...Full Text Available

2010-02-01

484

4-17-03 8-page format copy - The Marshall Star - NASA  

Science.gov (United States)

Apr 17, 2003 ... cooktop, $35; JennAir, $50. 883-5168. Bowflex, all manuals and attachments included, $800. 426-3203. Punching bag for boxing training, ...

485

Research of the ecosystem in coastal Baltic waters. Trace analysis under prior consideration of selenium and molybdenum. Final report; Oekosystemforschung in Litoralgewaessern der Ostsee. Spurenanalytik unter besonderer Beruecksichtigung von Selen und Molybdaen. Schlussbericht  

Energy Technology Data Exchange (ETDEWEB)

To study the biogeochemical behaviour, mobility and transport of trace metals in seawater (Se, Mo, Cd, Pb, Hg, Cu, Co, Fe, Ni, Zn), in suspended particulate matter (Mo, Cd, Pb, Cu, Co, Fe, Ni, Zn, Al, Mn) and in sediments of the inner and outer coastal regions, samples were collected on 3 separate cruises during a one year period (Mai 1993 - April 1994) at 20 stations in the coastal area of Mecklenburg-Vorpommern. Standard hydrographic parameters, nutrients and dissolved oxygen were also measured. Priority was taken to establish the methods for the determination of molybdenum and selenium. To study the behaviour of these two elements in detail, longterm measurements were carried out weekly between January 1993 and June 1994 at the `Messsteg/Warnemuende`. Because of parallel measurements correlations to biological, chemical and hydrographic parameters have been tested. The total database is summarized in the Appendix. The results are presented in 30 figures and 13 tables and are ...

1995-04-01

486

Production and Purification of UO_3 from rock phosphate deposits and its characterization  

International Nuclear Information System (INIS)

This study was carried out mainly to produce uranium trioxide (UO_3), matching standard commercial specification from rock phosphate deposits in Uro and Kurun at eastern part of the Nuba Mountains. A simplified hydrometallurgical procedure has been adopted for production of yellow cake from the ore. The powdered ore sample was leached with concentrated H_2SO_4 acid with and without addition of KCIO_3 as an oxidant. The crude yellow cake was precipitated from the resulting green solution of phosphoric acid as Na_2U_2O_7 and (NH_4)_2U_2O_7 and subsequently purified by TBP extraction (tributylphosphate) and hydrogen peroxide as UO_4.2H_2O. TBP purified product was dried and calcined to UO_3 whereas UO_4.2H-2O was dried and reduced to UO_3 by Na_2S_2O_3. Prior to precipitation of crude yellow cake, Fe in the phosphoric acid solution was precipitated using magnesia. Elemental analysis has shown that the ore is rich in Ca and deficient in elements of potential interest such as Fe, Cu and Zn. ...

2005-03-01

487

Progress in developing a portable blood irradiator for medical applications  

International Nuclear Information System (INIS)

This year was spent in perfecting details of the new design blood irradiator, i.e., having male fittings made for shunt insertion and in acquiring preliminary biological data on its effectiveness. Fabrication of units was slowed by an unanticipated reaction of the resin with the steel injection mold, by occasional thrombogenic flaws in the blood interface layer, by thrombus formation at the points of connection to the shunt and by nonavailability of a reactor for activating the "1"6"9Tm to "1"7"0Tm. The remaining unsolved problem is that of thrombus formation at the connectors.

1977-05-01

488

Positronium formation in liquid nitrogen as a function of electric field  

International Nuclear Information System (INIS)

The intensity of the orthopositronium component and its lifetime have been measured in liquid nitrogen as a function of electric field. While the lifetime remains constant at about 12.5 ns, the fraction of positronium formed is about 20% at zero field and decreases monotonically to an asymptotic value near 6% as the field is raised to 3.2 MV m"-"1. The decrease is roughly exponential with a drop off rate of 2.0 MV m"-"1. The results are a further indication of the importance of Mogensen's spur mechanism in the positronium formation process. (author).

1993-07-01

489

Overview of macroautophagy regulation in mammalian cells  

British Library Electronic Table of Contents (United Kingdom)

Macroautophagy is a multistep, vacuolar, degradation pathway terminating in the lysosomal compartment, and it is of fundamental importance in tissue homeostasis. In this review, we consider macroautophagy in the light of recent advances in our understanding of the formation of autophagosomes, which are double-membrane-bound vacuoles that sequester cytoplasmic cargos and deliver them to lysosomes. In most cases, this final step is preceded by a maturation step during which autophagosomes interact with the endocytic pathway. The discovery of AuTophaGy-related genes has greatly increased our knowledge about the mechanism responsible for autophagosome formation, and there has also been progress in the understanding of molecular aspects of autophagosome maturation. Finally, the regulation of au...

2010-01-01

490

Origin of binary stars  

Energy Technology Data Exchange (ETDEWEB)

Results of analytical study of early stages of a single star evolution are used investigation of the rotational fragmentation of the collapsing gas-dust cloud which leads to formation of two types of binaries. Wide ..cap alpha..-systems (Psub(orb) > or approximately 100 yrs) with usually unequal masses of components are formed before the formation of gas-dust core in hydrostatical equilibrium. Close ..beta..-systems (Psub(orb) < or approximation 100 yrs) with usually nearly equal masses of components are formed in the course of the collapse of gas-dust core.

1983-03-01

491

Multi-nucleon transfer reactions and the formation of light charged particles in the system sup(nat)Ag + /sup 40/Ar(285MeV)  

Energy Technology Data Exchange (ETDEWEB)

In the reaction sup(nat)Ag + /sup 40/Ar (285 MeV) there have been measured the energy spectra of the isotopes of elements from H to Cl at an emission angle of 40/sup 0/, the energy spectra and angular distributions of /sup 1/H, /sup 2/H, /sup 3/H, and /sup 4/He, and the angular distributions of Li, Be, B, and C. The contribution from multinucleon transfer reactions to the formation of light charged particles is discussed.

1981-11-01

492

Interference phenomena at the elastic collision of atoms with formation of the Feshbach resonance in the presence of laser radiation field  

British Library Electronic Table of Contents (United Kingdom)

Resonant scattering of atoms with formation of the Feshbach resonance in the presence of a laser radiation coupling the levels of two bound atoms (a molecule) is considered. The laser field leads to a second resonance in scattering and broadening of resonances, which facilitates the possibility of experimental observation of asymmetry of the total scattering cross-section arising because of interference between resonant and potential scatterings. The effects associated with interference of the two channels of decay of a bound system of two atoms (a molecule) in the laser field are studied. An expression is obtained for the scattering length in collision of two cold atoms in the field of laser radiation.

2011-01-01

493

Influence of surface layers on the formation of the electrophysical properties of heterogeneous polymer systems  

British Library Electronic Table of Contents (United Kingdom)

There is investigated the role of polymer layers on the metal surface of a fine filler in the formation of a PVC system with electrophysical properties. It is shown that a physicochemical polymer modification takes place under the surface active center influence. Thus, the surface layer properties (density and geometrical characteristics) differ from the PVC ones. The correlation between the electrophysical properties of the PVC composite and the surface layer in the range of the fine copper fraction of 0?11.3 vol % at E ? 106 V m?1 and a frequency response of 20?2 ? 105 Hz is determined. An explanation of the investigated relation is presented.

2008-01-01

494

Formation of oriented nanocrystals in an amorphous alloy by focused-ion-beam irradiation  

International Nuclear Information System (INIS)

Structural changes of a Ni-P amorphous alloy under focused-ion-beam (FIB) irradiation have been examined using transmission electron microscopy. On the irradiated plane, the formation of crystallographically orientated nanosized crystals (NCs), with the particle size of approximately 10 nm, was observed. A series of electron diffraction analyses have revealed that NCs have a face-centered-cubic (fcc) structure and the following orientation relationships between the NCs and the FIB direction were found. These are, irradiated plane//(111)_f_c_c and FIB direction//_f_c_c.

2002-12-09

495

Formation and stability of self-assembled coherent islands in highly mismatched heteroepitaxy  

CERN Document Server

We study the energetics of island formation in Stranski-Krastanow growth within a parameter-free approach. It is shown that an optimum island size exists for a given coverage and island density if changes in the wetting layer morphology after the 3D transition are properly taken into account. Our approach reproduces well the experimental island size dependence on coverage, and indicates that the critical layer thickness depends on growth conditions. The present study provides a new explanation for the (frequently found) rather narrow size distribution of self-assembled coherent islands.

1999-01-01

496

Effect of water on the formation of HSO/sub 3//sup -/ ions upon SO/sub 2/ adsorption onto faujasite-type zeolites  

Energy Technology Data Exchange (ETDEWEB)

SO/sub 2/ adsorption onto faujasite-type zeolites (Na-X, Na-Y) was investigated by combined UV and IR spectroscopy. Formation of chemisorbed HSO/sub 3//sup -/ species, indicated by a UV band around 215 nm and a low-frequency IR band at 1240 cm/sup -1/, was shown to depend significantly upon the presence of water. Differences in the behavior of Na-X and Na-Y were discussed in terms of different site populations.

1987-01-01

497

Effect of different fuels on the strontium hexaferrite nanopowder synthesized by a surfactant-assisted sol-gel auto-combustion method  

British Library Electronic Table of Contents (United Kingdom)

In this research a sol-gel auto-combustion route has been proposed to synthesize strontium hexaferrite nanopowder, using metal nitrates, ammonia as pH adjusting agent, n-decyltrimethylammonium bromide as a cationic surfactant and different fuels such as citric acid, glycine, acetylacetone and oxalic acid. The formation temperature of strontium hexaferrite and its crystallite size in presence of different fuels were compared together. The results showed the lowest formation temperature as well as the smallest crystallite size in the presence of citric acid as 900degreeC and 37.3nm respectively.

2007-01-01

498

Chiral crystallization and the origin of chiral life on earth  

British Library Electronic Table of Contents (United Kingdom)

Abstract The creation of chirality on Earth and the development of chiral life have been discussed in this highlight. Convincing evidence for the introduction of chirality on Earth is still fragmentary. We believe that by a combination of chiral crystallization and formation of helical polymers with preferred chiral conformational structure is the key to this question. This concept of macromolecular asymmetry has inspired ideas and resulted in possible rules for how chiral life as we know it, could have been introduced. These investigations needed the understanding of the requirements for chiral crystallization, for the stereochemistry of the initial formation of helical polymers, the measurements of optical activity of solids and their coordination with the fundamentals of chirality. Spac...

2011-01-01

499

Anion formation from gaseous and condensed molecules on low-energy electron impact  

International Nuclear Information System (INIS)

The interaction of free electrons in the energy range from 0 to 10 eV with molecules at different stages of aggregation is investigated. The mechanism in the gas phase under single collision conditions is described. Fullerenes C_6_0 and C_7_0 are used as targets. Electron impact on condensed molecules can lead to temporary negative ions. The formation of Cl"- from gas phase CCl_4 and the desorption of Cl"- from 6 monolayer CCl_4 film on an Au substrate is determined experimentally. (Suda).

1994-03-20

500

A hierarchical lattice structure and formation mechanism of ZnO nano-tetrapods  

International Nuclear Information System (INIS)

The existence of characteristic longitudinal optical and transverse optical phonons of cubic ZnO in ZnO nano-tetrapods is determined by Raman spectroscopy and first-principles calculations. Stacking sequence change at the boundary of the core and legs is also identified by high-resolution transmission electron microscopy. Based on this experimental and theoretical evidence, we demonstrate that the lattice structure of ZnO nano-tetrapods is hierarchical with a zinc blende core connecting to four wurtzite legs. Furthermore, we establish the atomic configuration and propose a formation mechanism induced by Laplace pressure in the initial growth stage of ZnO nano-tetrapods.

2009-08-12