WorldWideScience
1

Technical description of parameters influencing the pH value of suspension absorbent used in flue gas desulfurization systems.  

Science.gov (United States)

As a result of the large limestone deposits available in Poland, the low cost of reagent acquisition for the largescale technological use and relatively well-documented processes of flue gas desulfurization (FGD) technologies based on limestone sorbent slurry, wet scrubbing desulfurization is a method of choice in Poland for flue gas treatment in energy production facilities, including power plants and industrial systems. The efficiency of FGD using the above method depends on several technological and kinetic parameters, particularly on the pH value of the sorbent (i.e., ground limestone suspended in water). Consequently, many studies in Poland and abroad address the impact of various parameters on the pH value of the sorbent suspension, such as the average diameter of sorbent particles (related to the limestone pulverization degree), sorbent quality (in terms of pure calcium carbonate [CaCO3] content of the sorbent material), stoichiometric ...

2010-08-01

2

Behavior of Aqueous Electrolytes in Steam Cycles - The Final Report on the Solubility and Volatility of copper(I) and Copper(II) Oxides  

Energy Technology Data Exchange (ETDEWEB)

Measurements were completed on the solubility of cupric and cuprous oxides in liquid water and steam at controlled pH conditions from 25 to 400 C (77 to 752 F). The results of this study have been combined with those reported from this laboratory in two previous EPRI reports to provide a complete description of the solubility of these oxides and the speciation of copper dissolved in liquid water and steam as a function of oxidation state, temperature, pH, and in the case of steam, pressure. These constitute the first set of reliable data for cuprous oxide solubility over this range of conditions. For the more intensively studied CuO case, agreement was found between our results and those of previous studies of its solubility in steam, whereas only partial agreement was evident for its solubility in liquid water. For both oxides this disagreement often amounted to orders of magnitude. The solubility of ...

2004-05-01

3

Modification of streaming potential by precipitation of calcite in a sand-water system: laboratory measurements in the pH range from 4 to 12  

British Library Electronic Table of Contents (United Kingdom)

SUMMARY Spontaneous potentials associated with volcanic activity are often interpreted by means of the electrokinetic potential, which is usually positive in the flow direction (i.e. Zeta potential of the rock is negative). The water-rock interactions in hydrothermal zones alter the primary minerals leading to the formation of secondary minerals. This work addresses the study of calcite precipitation in a sand composed of 98 per cent quartz and 2 per cent calcite using streaming potential measurements. The precipitation of calcite as a secondary mineral phase, inferred by high calcite saturation indices and by a fall in permeability, has a significant effect on the electrokinetic behaviour, leading to a significant reduction in the Zeta potential (in absolute value) and even a change in si...

2006-01-01

4

Experimental Evaluation of Tude Support Plate Crevice Chemistry  

Energy Technology Data Exchange (ETDEWEB)

A test methodology for measuring temperature, impedance, pH, and electrochemical potential distributions within a sludge-packed tube support plate crevice in a laboratory test is described. The method successfully showed that there were large concentration gradients between the tube and tube support plate sides of the crevice. The testing also showed that strong bases concentrated more effectively than strong acids, and that the crevice pH, when exposed to seawater-based solutions, increased with increasing superheat and decreasing bulk concentration. The large variations in the crevice chemistry observed under heat transfer were eliminated upon shutdown. These new test data suggest that it might be beneficial to evaluate the variation in the extent of stress corrosion cracking with tube support plate elevation found in some steam generators in light of local chemistry changes, as well as the variation ...

2001-05-08

5

Coal slurry pH studies  

Energy Technology Data Exchange (ETDEWEB)

Coal slurry pH values can be used to characterize coals. pH values depend on the coal, time since slurry preparation, contact with gas atmosphere, particle size, and stirring. Measured values reflect a sequence of reactions including: carbon dioxide absorption by water from the air, wetting of the coal (pH may be affected by the elemental composition of the mineral matter), and further equilibration with species in the water. The pH initially drops as carbon dioxide is absorbed, then rapidly increases as the coal is wetted, and then slowly decreases as some reactions with species in the water take place.

1995-12-01

6

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

Energy Technology Data Exchange (ETDEWEB)

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

1994-03-01

7

European multicentre evaluation of the Super Aution SA-4220 urinalysis analyser.  

Science.gov (United States)

A multicentre evaluation of the urine test strip analyser Super Aution-4220 was carried out in six laboratories. The analytical performance of the instrument with regard to imprecision, linearity, detection limit, drift, carry-over and method comparison was studied. Using the Aution stick 8 test strip the pH, glucose, protein, ketones, bilirubin, blood, urobilinogen and leukocyte esterase were analysed. Specific gravity measurements were performed by refractive index method. Within-run and between-run imprecision determined at three levels of analyte were good. No carry-over was observed. Obtained results were linear through all the described analytical range. No significant drift was detected. Method comparison with some quantitative methods was performed and showed a good correlation with most of the analytes. The study of interferences showed minor interferences by common therapeutic drugs with the ...

1998-12-01

8

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

Science.gov (United States)

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

2004-12-01

9

Memories of John N. Brady: scientist, mentor and friend  

UK PubMed Central (United Kingdom)

Friends and colleagues remember John N. Brady, Ph.D., Chief of the Virus Tumor Biology Section of the Laboratory of Cellular Oncology, who died much too young at the age of 57 on April 27, 2009 of colon...Full Text Available

10

Automation in urinalysis: evaluation of three urine test strip analysers  

UK PubMed Central (United Kingdom)

A clinical laboratory evaluation was conducted on the Clinitek Auto 2000, the Super Aution Analyzer and the Urotron RL9 for the determination of glucose, protein, pH, blood, ketone-bodies and bilirubin....Full Text Available

1988-01-01

11

A non-invasive approach for the determination of rumen pH  

Environmental Research Database

DescriptionAt present, measurement of rumen pH for differnt diets and feeding regimes is only possible through direct sampling of the rumen fluid. Such invasive procedures are not practical at the farm level and they have ethical implications for research programmes. This approach also has limitations to its reliability due to spatial variations in acidity within the rumen. Mathematical modelling offers a non-invasive real-time alternative for monitoring rumen pH, and the purpose of the research propose [continued...

2004-01-31

12

Acid mine drainage and its impact in the Black Creek watershed, Virginia  

International Nuclear Information System (INIS)

A one-year study was conducted to determine the impacts of acid min drainage (AMD) on the Black Creek watershed in Wise County, Virginia. Water quality, metal content of sediment and water column, soil pH, macroinvertebrate assemblages, habitat assessment and toxicity testing were used to assess the impact in the watershed. A total of 22 sites in the creek and surrounding watershed were actively monitored. This included six primary sources of AMD. Conductivity measurements > 1,000 microhmos/cm were found at eight sites and pH was consistently below 6.0 at seven. Of six metals analyzed, magnesium was highest in the water column, ranging from 16.5 mg/L to 130 mg/L. Aluminum and iron were both elevated in the sediment with iron concentrations as high as 176,000 mg/kg. An increase in sediment metal concentrations was noted when progressing downstream in the creek. Of nine high wall and spoils areas sampled, soil ...

1996-11-17

13

Effect of lead and silicon on localized corrosion of Alloy 800 in steam generator crevice environments  

Energy Technology Data Exchange (ETDEWEB)

The Alloy 800 tubes used in CANDU 6 steam generators have not experienced significant corrosion damage to date, which may be attributed to successful water chemistry control strategies. However, it is known that Alloy 800, like other steam generator (SG) tubing materials, is not immune to corrosion, especially pitting, under some plausible but off-specification operating scenarios. Electrochemical measurements provide information on corrosion susceptibility and rate, which are known to be a function of water chemistry. Using laboratory data in combination with chemistry monitoring and diagnostic software it is possible to assess the impact of plant operating conditions on SG tube corrosion for plant life management (PLIM). In this context, this paper discusses the results of electrochemical measurements made to elucidate the corrosion behaviour of Alloy 800 SG tubes under conditions simulating those plausible in SG ...

2001-09-01

14

Statement of work for analytical services provided by PNNL`sanalytical chemistry laboratory  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this statement of work (SOW) is to establish laboratory analytical criteria and requirements for radioactive airborne emissions measurement sample and/or analysis activities.

1997-06-30

15

Effects of variable hardness, ph, alkalinity, suspended clay, and humics on the chemical speciation and aquatic toxicity of copper  

Science.gov (United States)

The effects of variable hardness, pH, alkalinity, humics, and suspended clay on the chemical speciation of copper and its toxicity to fathead minnow larvae in Lake Superior water were investigated. Two proposed methods (toxicity factors and chemical speciation) for predicting LC50 values in specific natural waters from laboratory toxicity data and the average site specific values of general water quality parameters were evaluated. The accuracy of the cupric ion-selective electrode in determining CU/sup +2/ activities in ambient and chemically altered Lake Superior water was also determined.

1986-03-01

16

Anaerobic thermophilic bacteria isolated from a Venezuelan oil field and its potential use in microbial improved oil recovery  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work is to determine the ability of indigenous bacteria from a Venezuelan oil field to grow under reservoir conditions inside a porous media, and to produce metabolites capable of recovering residual crude oil. For this purpose, samples of formation waters from a central-eastern Venezuelan oil reservoir were enriched with different carbon sources and a mineral basal media. Formation water was used as a source of trace metals. The enrichments obtained were incubated at reservoir temperature (71{degrees}C), reservoir pressure (1,200 psi), and under anaerobic conditions for both outside and inside porous media (Berea core). Growth and metabolic activity was followed outside porous media by measuring absorbance at 660 nm, increases in pressure, and decreases in pH. Inside porous media bacterial activity was determined by visual examination of the produced waters (gas bubbles and bacterial cells). All the carbohydrates tested ...

1995-12-31

17

Measurement and interpretation of delayed photoneutron effects in multizone criticals with partial D{sub 2}O moderation  

Energy Technology Data Exchange (ETDEWEB)

The effective fraction of delayed photoneutrons ({beta}{sup ph}) has been theoretically defined and experimentally determined in various different configurations of the LWR-PROTEUS critical facility. The peculiarity lies in the fact that the reactor has D{sub 2}O in only one of the four fuelled zones, thus D({gamma},n)H reactions take place mainly in this region. The work is divided into three parts. The first part is devoted to the description of the LWR-PROTEUS facility and to the measurements of {beta}{sup ph}. These experimental values are derived from standard inverse-kinetics analysis of neutron flux decay experiments for each of seven different configurations, with nine additional groups of neutron precursors to account for photoneutron effects. In the second part, the coupled neutron and gamma Boltzmann equations are reduced to exact point kinetics equations using the photon infinite-velocity approximation, and then ...

2003-11-01

18

Capacitance behaviour of passive films on ferritic and austenitic stainless steel  

Energy Technology Data Exchange (ETDEWEB)

The electrochemical behaviour of passive films formed on one austenitic stainless steel (AISI 304) and one ferritic stainless steel (AISI 446) in solutions with pH between 0.6 and 8.4 was studied by capacitance measurements and photocurrent spectroscopy. Compositional characterization of the passive films was done by X-ray photoelectron spectroscopy. The capacitance increases with decreasing pH. Doping densities evaluated from Mott-Schottky plots are in the range 2-6 x 10{sup 20} cm{sup -3} and increased with the pH in the neutral/alkaline range while in pH 0.6, values above 10{sup 21} cm{sup -3} were found. The bandgap energy indicates two transitions, at 2.5-2.8 and 3.2 eV. The analytical data reveal that, as the pH increased, the films become enriched in Fe(II) and Fe(III), whereas the Cr(III) gradually decreases. The films formed at very low ...

2005-03-01

19

Capacitance behaviour of passive films on ferritic and austenitic stainless steel  

International Nuclear Information System (INIS)

The electrochemical behaviour of passive films formed on one austenitic stainless steel (AISI 304) and one ferritic stainless steel (AISI 446) in solutions with pH between 0.6 and 8.4 was studied by capacitance measurements and photocurrent spectroscopy. Compositional characterization of the passive films was done by X-ray photoelectron spectroscopy. The capacitance increases with decreasing pH. Doping densities evaluated from Mott-Schottky plots are in the range 2-6 x 10"2"0 cm"-"3 and increased with the pH in the neutral/alkaline range while in pH 0.6, values above 10"2"1 cm"-"3 were found. The bandgap energy indicates two transitions, at 2.5-2.8 and 3.2 eV. The analytical data reveal that, as the pH increased, the films become enriched in Fe(II) and Fe(III), whereas the Cr(III) gradually decreases. The films formed at very low pH had a ...

2005-03-01

20

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 ...

1994-07-01

21

Augmenting Clinical Evaluation of Hemiparetic Arm Movement With a Laboratory-Based Quantitative Measurement of Kinematics as a Function of Limb Loading  

UK PubMed Central (United Kingdom)

BackgroundKinematic and kinetic measurements used in laboratory settings can quantify upper extremity movement impairment following stroke, but their relationship...Full Text Available

2008-01-01

22

Wetland treatment of oil and gas well wastewaters. Quarterly technical report, May 25, 1993-August 24, 1993  

Energy Technology Data Exchange (ETDEWEB)

In the third quarterly report adsorption of heavy metals ions such as Cu(II) and Cr(VI) onto soils drawn from the laboratory-type wetland was shown to be weak. Secondly, it was shown that modified-clays did adsorb Cr(VI) ions strongly at pH 4.5. Further, studies on the pH dependence of the adsorption of {beta}-naphthoic acid, (NA), a well-documented contaminant in many oil and gas well waste waters onto modified-clays were undertaken and it was shown that uptake of NA by modified-clays was of the high affinity type at pH 4.5 and 7.0, but weak at pH 9.0. Adsorption of heavy metal ions, Cu{sup 2+}, and Cr(VI) onto algae, a proposed wetland amendment, was carried out and the results were presented and discussed in the fourth quarterly report. Uptake of NA by the soil component of the laboratory-type wetland was monitored as a function of pH. ...

1993-10-04

23

Influence of pH on the passivation behavior of 254SMO stainless steel in 3.5% NaCl solution  

Energy Technology Data Exchange (ETDEWEB)

The potentiodynamic polarization measurement of 254SMO stainless steel (UNS 31254) was conducted in 3.5% NaCl solutions with pH ranging from 0.1 to 5. The results indicated that this stainless steel offered excellent pitting corrosion resistance in corrosive environments. Further, it also exhibited various features on the polarization curves in different pH solutions. The electrochemical constant-potential passivation treatment performed at different pH followed by XPS analysis revealed that the primary constituents of the outermost layer of the passive films formed in the weak (pH 5) and strong (pH 0.8) acid solutions are iron oxides and Cr{sub 2}O{sub 3} and Cr(OH){sub 3}, respectively. Molybdenum oxides, primarily in the six-valence state, existed in the outermost layer of the passive film. Only very weak signals corresponding to that of nickel oxides were ...

2007-05-15

24

Influence of pH on the passivation behavior of 254SMO stainless steel in 3.5% NaCl solution  

International Nuclear Information System (INIS)

The potentiodynamic polarization measurement of 254SMO stainless steel (UNS 31254) was conducted in 3.5% NaCl solutions with pH ranging from 0.1 to 5. The results indicated that this stainless steel offered excellent pitting corrosion resistance in corrosive environments. Further, it also exhibited various features on the polarization curves in different pH solutions. The electrochemical constant-potential passivation treatment performed at different pH followed by XPS analysis revealed that the primary constituents of the outermost layer of the passive films formed in the weak (pH 5) and strong (pH 0.8) acid solutions are iron oxides and Cr_2O_3 and Cr(OH)_3, respectively. Molybdenum oxides, primarily in the six-valence state, existed in the outermost layer of the passive film. Only very weak signals corresponding to that of nickel oxides were detected in the ...

2007-05-01

25

Limestone Dissolution in Flue Gas Desulfurization Processes.  

Science.gov (United States)

The report gives results of the measurement of dissolution rates of reagent CaCO3 and commercial limestones (9 types/19 grinds) at constant pH and solution composition by batch titration with HC1. Conditions were selected to simulate flue gas desulfurizat...

1983-01-01

26

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

UK PubMed Central (United Kingdom)

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

1987-07-01

27

Quality assurance handbook for measurement laboratories  

International Nuclear Information System (INIS)

This handbook provides guidance in the application of quality assurance to measurement activities. It is intended to help those persons making measurements in applying quality assurance to their work activities by showing how laboratory practices and quality assurance requirements are integrated to provide control within those activities. The use of the guidance found in this handbook should help provide consistency in the interpretation of quality assurance requirements across all types of measurement laboratories. This handbook also can assist quality assurance personnel in understanding the relationships between laboratory practices and quality assurance requirements. The handbook is composed of three chapters and several appendices. Basic guidance is provided by the three chapters. In Chapter 1, the role of quality assurance in obtaining quality data and the ...

28

Electrochemical and conversion electron Moessbauer study of corrosion induced by acid rain  

Energy Technology Data Exchange (ETDEWEB)

The passivation of low carbon steel was studied in aqueous solution of 0.5M Na[sub 2]SO[sub 4]+0.001M NaHSO[sub 3] (pH 3.5, 6.5 and 8.5) which can be considered as a model of acid rain. The used conversion electron Moessbauer spectroscopy (CEMS) with the complementary electrochemical investigations proved that the sulfite ions induce pitting corrosion at pH 3.5 and 6.5, while the measurements showed much weaker pitting at pH 8.5. The compositions and thicknesses of the passive films formed during the electrochemical treatments are determined from the CEM spectra. Only [gamma]-FeOOH was found on the surface of the samples at pH 6.5 and 8.5. Nevertheless, at pH 3.5 the sextet belonging to Fe[sub 3]C appears in the spectra, and also FeSO[sub 4].H[sub 2]O could be detected in low concentration. (orig.).

1993-04-01

29

Strontium removal from caustic carbonate waste solutions using carrier coprecipitation  

Energy Technology Data Exchange (ETDEWEB)

A carrier coprecipitation procedures has been developed for the removal of radioactive strontium from caustic liquid low-level waste (LLLW) generated at Oak Ridge National Laboratory. The two-step treatment process involves the addition of normal Sr (as SrCl{sub 2}) to the waste matrix, which is composed primarily of 0.3 M NaOH and 0.6 M Na{sub 2}CO{sub 3}. The active Sr equilibrates with the normal Sr carrier and coprecipitates as SrCO{sub 3} at pH 13. A liquid/solid separation is made before the pH of the supernate is reduced to pH 8 with sulfuric acid. During the neutralization step, the aluminum is the waste precipitates as Al(OH){sub 3}. Further Sr decontamination is achieved as traces of active Sr sorb to the Al(OH){sub 3} that precipitates during the neutralization step. A final liquid/solid separation is made at pH 8 to remove the sorbed active Sr. Maximum Sr decontamination ...

1994-12-31

30

Matrix diffusion studies by electrical conductivity methods. Comparison between laboratory and in-situ measurements  

Energy Technology Data Exchange (ETDEWEB)

Traditional laboratory diffusion experiments in rock material are time consuming, and quite small samples are generally used. Electrical conductivity measurements, on the other hand, provide a fast means for examining transport properties in rock and allow measurements on larger samples as well. Laboratory measurements using electrical conductivity give results that compare well to those from traditional diffusion experiments. The measurement of the electrical resistivity in the rock surrounding a borehole is a standard method for the detection of water conducting fractures. If these data could be correlated to matrix diffusion properties, in-situ diffusion data from large areas could be obtained. This would be valuable because it would make it possible to obtain data very early in future investigations of potentially suitable sites for a repository. This study ...

1998-09-01

31

Extraction-spectrophotometric determination of terbium in its mixture with lanthanum  

International Nuclear Information System (INIS)

A spectrophotometric study of the extraction with isobutanol of rare-earth elements in the form of complexes with quinoilizarin and N-benzene-N-phenylhydroxylamine has been made. The purpose of the study is to find out whether this reaction can be used in determining the concentration of elements in the presence of other rare-earth elements. In determining the relationship between the pH and light absorption the pH of the solution is measured after the extraction. The extraction of complexes begins at pH approximately 4 and reaches a maximum at pH7-8 (for La) and pH6-9 (for Er). The complexes underge decomposition when pH of the solution increased. The composition of complex compounds is determined by spectrophotometric methods for isomolar series, molar ratios and from the slope of logarithmic plots. Under optimal conditions ...

1975-01-01

32

A study of electrochemically-induced corrosion of low carbon steel in a medium modelling acid rain  

Energy Technology Data Exchange (ETDEWEB)

Complementary electrochemical, spectrophotometric and electron microsopic investigations were made in addition to the conversion electron Moessbauer spectroscopic (CEMS) measurements to learn more about the mechanism of corrosion of low carbon steel samples in aqueous sulfate and sulfite containing sulfate solutions (pH 3.5, 6.5 and 8.5). Passivation of iron in pure sulfate solution was studied in detail in earlier papers. In the present work, we used a solution containing both sulfate and sulfite anions to obtain more information about the effect of acid rain on low carbon steel samples. The compositions and thicknesses of the passive films formed due to the electrochemical treatments were determined from the CEM spectra. [gamma]-FeOOH was found in each case on the surface of the samples; nevertheless, at pH 3.5 the sextet belonging to Fe[sub 3]C appears in the CEM spectra, and also FeSO[sub 4] . H[sub 2]O was detected in ...

1994-11-01

33

Removal of boron from aqueous solution by using neutralized red mud  

International Nuclear Information System (INIS)

The adsorptive removal of boron from aqueous solution by using the neutralized red mud was studied in batch equilibration technique. The effects of pH, adsorbent dosage, initial boron concentration and contact time on the adsorption were investigated. The experiments demonstrated that boron removal was of a little fluctuation in pH range of 2-7 and it takes 20 min to attain equilibrium. The adsorption data was analyzed using the Langmuir and the Freundlich isotherm models and it was found that the Freundlich isotherm model represented the measured sorption data well.

2007-04-02

34

Effect of chloride concentration and pH on pitting corrosion of waste package container materials  

Energy Technology Data Exchange (ETDEWEB)

Electrochemical cyclic potentiodynamic polarization experiments were performed on several candidate waste package container materials to evaluate their susceptibility to pitting corrosion at 90 degrees C in aqueous environments relevant to the potential underground high-level nuclear waste repository. Results indicate that of all the materials tested, Alloy C-22 and Ti Grade-12 exhibited the maximum corrosion resistance, showing no pitting or observable corrosion in any environment tested. Efforts were also made to study the effect of chloride ion concentration and pH on the measured corrosion potential (Ecorr), critical pitting and protection potential values.

1996-12-01

35

Low-pH injection grout for deep repositories. Summary report from a co-operation project between NUMO (Japan), Posiva (Finland) and SKB (Sweden)  

Energy Technology Data Exchange (ETDEWEB)

The use of standard cementitious material creates pulses of pH in the magnitude of 12-13 in the leachates and release alkalis. Such a high pH is detrimental and also unnecessarily complicates the safety analysis of the repository. As no reliable pH-plume models exist, the use of products giving a pH below 11 in the leachates facilitates the safety analysis. Also, according to current understanding, the use of low-pH cement (pH = 11) will not disturb the functioning of the bentonite, although limiting the amount of low-pH cement is recommended. A result of the project is that there are both low-pH cementitious material for grouting larger fractures (= 100 {mu}m) and non-cementitious material for grouting smaller fractures (< 100 {mu}m) that will, after further optimisation work, be recommended for grouting of deep repositories. This project concentrated on the technical development of properties ...

2005-06-01

36

Pitting corrosion of welded joints of chromomanganese with nitrogen austenite steel  

International Nuclear Information System (INIS)

The tendency of welded joints from 10Kh14AG15 and 10Kh14AG9 steels to pitting corrosion under the conditions of operating blast-furnace gas purification scrubbers has been investigated. Water in scrubbers contains various quantities of chlorides and sulfates, has pH from 6 to 9 and temperature 65-75 deg. The laboratory corrosion tests have been carried out also on samples turned from the heat-affected zone (h.a.z.) of welded plates at 20 and 65 deg. Anode polarization curves have been read from the Vk corrosion potential at potential shifting rate 0.01 V/min. It is established that in most rigid conditions of scrubbers operating pitting corrosion (PC) rate of chrome-manganese nitrogen-containing steel can reach 2.5 mm/year. At high content of chlorides in water the elevated temperature and external tensile stresses intensify PC. The resistance of welded joints to PC when using welding materials on chromonickel molybdenum base is determined in ...

37

Environmental Measurements Laboratory fiscal year 1998: Accomplishments and technical activities  

Energy Technology Data Exchange (ETDEWEB)

The Environmental Measurements Laboratory (EML) is government-owned, government-operated, and programmatically under the DOE Office of Environmental Management. The Laboratory is administered by the Chicago Operations Office. EML provides program management, technical assistance and data quality assurance for measurements of radiation and radioactivity relating to environmental restoration, global nuclear nonproliferation, and other priority issues for the Department of Energy, as well as for other government, national, and international organizations. This report presents the technical activities and accomplishments of EML for Fiscal Year 1998.

1999-01-01

38

Laboratory studies of gas generation and potential for tank wall corrosion during blending of high-level wastes at the West Valley Demonstration Project  

Energy Technology Data Exchange (ETDEWEB)

Laboratory experiments were conducted to simulate the transfer of acidic THOREX waste from Tank 8D-4 into the alkaline PUREX waste in Tank 8D-2 at West Valley. The purpose of the experiments was to explore means of minimizing the production of nitric oxide (NO) gas during mixing of the two wastes and to assess the potential for the gas to further react in the vapor space possibly leading to enhanced corrosion of the tank walls. Forty one THOREX/PUREX mixing tests were conducted to explore the effects of stirring rate, pH, THOREX addition rate, THOREX or PUREX dilution, and temperature. The two most important criteria for minimizing NO production were to maintain some degree of agitation and the keep the pH in the PUREX high, preferably >12. Steel corrosion tests were performed in the presence of low partial pressures of NO{sub 2} and liquid water or water vapor. The NO{sub 2} (from oxidation of NO in the vapor space) ...

1995-05-01

39

Lysozyme dimer formation on lysozyme oxidation with B./2 as studied by fluorescence evolution  

International Nuclear Information System (INIS)

Lysozyme dimers produced on oxidation of lysozyme with Br_2anion radicals in aqueous solutions exhibit a fluorescence spectrum (lambdasub(max) = 400 nm) closely similar to that of bi-tyrosine. This suggests that the dimer is likely to have a tyrosine-tyrosine bond resulting from the combination of tyrosine phenoxy radicals of two lysozyme molecules. Kinetic studies on dimer formation were made by measuring time-dependent fluorescence after pulsed-electron irradiation over wide pH range. The results lead to the following conclusions. The second-order growth of the dimer fluorescence observed at pH 10.7-12.5 reflects the combination process of the lysozyme radicals, which is rate-determining in the pH range. On the other hand, the first-order growth observed at pH 6.8-10.2 is attributable to the enolization of the keto-form of the dimer. A tentative reaction scheme is proposed for the ...

40

Multi-centre evaluation of the urine test strip analyser Rapimat.  

Science.gov (United States)

A multi-centre evaluation of the test strip analyser, Rapimat, was performed by four laboratories following the ECCLS 2nd draft guidelines for the evaluation of analysers in clinical chemistry. Using the Rapignost urine test strip with the test fields for bilirubin, urobilinogen, acetoacetate, ascorbic acid, glucose, protein, nitrite, pH and haemoglobin, the Rapimat was found to be analytically reliable in comparison with other, in most cases quantitative procedures. During the observation period of about 6 months no breakdown occurred in any laboratory. Interferences and sensitivity as discussed for the bilirubin and urobilinogen test field are more related to the test strip than to the instrument. Several improvements for further developments are suggested. This multi-centre study has shown that the ECCLS protocol is applicable to analytical procedures leading to discrete results. PMID:4056663

1985-08-01

41

Influence of calcite on the electrokinetic treatment of a natural clay  

British Library Electronic Table of Contents (United Kingdom)

After presenting a geochemical model for the interaction between calcite and varying environmental conditions, the paper discusses the experimental results of long duration electrokinetic tests, run on a natural clayey soil in unbuffered conditions. Local measurements of electrical potential, temperature and water flow were performed during the tests, while pH and fluid conductivity were measured locally once the tests had been dismantled. Sharp change of pH and reduction of the soil electrical conductivity, that in pure clays usually occur in the proximity of the cathode, were observed in the region close to the anode. As well, the soil in the anode area systematically tended to develop fractures, that mostly persisted until the end of the experiments. The features observed, that are not ...

2009-01-01

42

Thermal conductivity of polyisocyanurate foam board insulation blown with CFC-11 substitutes: Laboratory and long-term field measurements  

Energy Technology Data Exchange (ETDEWEB)

This paper reports on a series of laboratory and controlled test site measurements of the thermal conductivity of polyisocyanurate foam laminated boardstock roof insulations produced with several different blowing agents; CFC-11, HCFC-123, HCFC-14lb, and two blends of the HCFCs. The behavior of the experimental foams with HCFCs is compared to that of conventional polyisocyanurate foam blown with CFC-11. Thermal drift observed from two years of field exposure is compared to laboratory accelerated aging tests and the laboratory and field measurement techniques are described. This work is part of a Joint Industry/Government Project established in the United States to evaluate the technical viability of HCFC alternative blowing agents for polyisocyanurate foam roof insulations.

1992-01-01

43

A mobile remote sensing laboratory for water vapor, trace gas, aerosol, and wind speed measurements  

Energy Technology Data Exchange (ETDEWEB)

The Lawrence Livermore National Laboratory has developed a mobile field laboratory for remote measurement of atmospheric processes and observables that are important in global climate change, dispersal of hazardous materials, and atmospheric pollution. Specific observables of interest are water vapor, trace gases, aerosol size and density, wind, and temperature. The goal is to study atmospheric processes continuously for extended periods in remote field locations. This laboratory has just reached field ready status with sensors for aerosol and trace gas measurement based on established techniques. A development program is underway to enhance the sensor suite with several new techniques and instruments that are expected to significantly extend the state of the art in remote trace gas analysis. The new sensors will be incorporated into the lab during the next two years.

1993-03-19

44

Clinical Correlates to Laboratory Measures for use in Non-Contact Anterior Cruciate Ligament Injury Risk Prediction Algorithm  

UK PubMed Central (United Kingdom)

BackgroundProspective measures of high knee abduction moment during landing identify female athletes at high risk for non-contact anterior cruciate ligament injury....Full Text Available

2010-08-01

45

Intercomparison of soil radon concentration measurements  

International Nuclear Information System (INIS)

In October last year the first intercomparison of measurements of the soil radon concentrations between various laboratories in Slovakia was realised. The organisation of this intercomparison was conducted by the Slovak Legal Metrology in Banska Bystrica together with the Slovak National Accreditation Service in Bratislava (SNAS). The scientific guarantee of the exercise was the State metrological Centre for radon quantities, which is working at the Research base of Slovak Medical University in Bratislava. The main objective of the intercomparison was to verify the correctness of the methods for the soil radon measurements of the authorised laboratories for radon volume activities in soil air. The intercomparison (signed as SLM ILC 3/03) was performed as a 'circular' metrology comparison, in accordance with a methodical directive MSA 0117-98, published by SNAS. Six laboratories were ...

2004-11-01

46

Reactivity of aliphatic amines toward platinum(II) complexes  

Energy Technology Data Exchange (ETDEWEB)

Reaction kinetics for the displacement of 5-aminoquinoline (5-Aq) and diethyl sulfide (SEt{sub 2}) from cis-[PtPh{sub 2}(CO)(L)] (L = 5-Aq or SEt{sub 2}) by aliphatic amines was measured for a wide array of amines. Reaction products were characterized by IR and NMR spectroscopies and crystalk structures of selected products were reported. Steric effects on the substitutions were discussed.

1994-08-31

47

Deposition and removal of sub-micron particles of magnetite at the surface of alloy 800. AECL research No. AECL-11015  

Energy Technology Data Exchange (ETDEWEB)

This report measured the rate of isothermal deposition of sub-micron particles of magnetite onto the surface of Alloy 800 at pH of 4.2-9.3 at Re=10,000 and a fluid temperature of 25C. Deposition is modelled as a two-step process, the transport of particles to the surface region followed by attachment to the surface.

1994-12-31

48

IMPROVED NATURAL GAS STORAGE WELL REMEDIATION  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the research conducted during Budget Period One on the project ''Improved Natural Gas Storage Well Remediation''. The project team consisted of Furness-Newburge, Inc., the technology developer; TechSavants, Inc., the technology validator; and Nicor Technologies, Inc., the technology user. The overall objectives for the project were: (1) To develop, fabricate and test prototype laboratory devices using sonication and underwater plasma to remove scale from natural gas storage well piping and perforations; (2) To modify the laboratory devices into units capable of being used downhole; (3) To test the capability of the downhole units to remove scale in an observation well at a natural gas storage field; (4) To modify (if necessary) and field harden the units and then test the units in two pressurized injection/withdrawal gas storage wells; and (5) To prepare the project's final ...

2001-12-01

49

Mitochondrial sequestration of BCECF after ester loading in the giant alga Chara australis  

British Library Electronic Table of Contents (United Kingdom)

Summary. Ratiometric fluorescent dyes are often used to monitor free ion concentrations in vivo, especially in cells that are recalcitrant to transformation with genetically encoded fluorescent markers. Although intracellular dye distributions are often found to be cytosolic, dye localisation has often not been examined in detail. We began exploring the use of BCECF (2?,7?-bis(2-carboxyethyl)-5(6)-carboxyfluorescein) to monitor pH in the giant alga Chara australis and discovered that younger leaf cells could be loaded using the acetoxymethyl ester of BCECF. However, we were puzzled to find in microphotometric measurements that the fluorescence ratio appeared insensitive to manipulations affecting cytosolic pH. Confocal imaging of C. australis cells loaded with BCECF showed an accumulation ...

2007-01-01

50

Electrochemical characterization and CFD simulation of flow-assisted corrosion of aluminum alloy in ethylene glycol-water solution  

British Library Electronic Table of Contents (United Kingdom)

An impingement jet system was used to study flow-assisted corrosion (FAC) of 3003 aluminum (Al) alloy in ethylene glycol-water solutions that simulates the automotive coolant by corrosion potential and electrochemical impedance spectroscopy (EIS) measurements as well as computational fluid dynamics (CFD) simulation. The effects of solution pH and fluid impact angle on Al FAC were determined. An increase of solution pH enhances the activity of Al due to dissolution of Al oxide film in alkaline environment. Moreover, Al activity decreases with the increasing fluid impact angle to the specimen. A CFD simulation shows that, with the increase of impact angle, the electrode area under high-velocity flow field decreases and that under low-velocity flow field increases. Consequently, the shear str...

2008-01-01

51

Dissolution rate of limestone for wet flue gas desulfurization in the presence of sulfite.  

Science.gov (United States)

Limestone dissolution rate was measured by a pH-stat method with CO(2) sparging and dissolved sulfite. The dissolution rate of limestone under these conditions was found to be controlled by mass transfer and surface kinetics. As can be seen from the results, in the presence of sulfite, limestone dissolution rate increases with increasing stirring speed, reaction temperature and CO(2) partial pressure. The crystallinity of limestone has a great impact on the dissolution rate: The lower the value of the crystallinity of limestone is, the higher the dissolution rate is. The presence of sulfite promotes the dissolution rate when pH value is below 5.5 but inhibits it when pH value is above 5.5. PMID:19359093

2009-03-11

52

Production of a cellulolytic enzyme system in mixed-culture solid-state fermentation of soybean hulls supplemented with wheat bran  

British Library Electronic Table of Contents (United Kingdom)

Solid-state fermentation of soybean hulls supplemented with wheat bran using a co-culture of Trichoderma reesei and Aspergillus oryzae was performed. Three parameters - initial moisture content, incubation temperature, and initial pH - were optimized in culture flasks using response surface methodology. Parameter optimization was carried out with respect to filter paper activity and b-glucosidase activity in the culture. Temperature of 30^oC, pH of 5, and moisture content of 70% were found to be optimum. Optimized parameters were used for laboratory scale-up in static tray fermenters. The maximum filter paper activity of 10.7FPU/g-ds and b-glucosidase of 10.7IU/g-ds were obtained after 96-h incubation period in static tray fermenters in agreement with optimized activities at shake flask le...

2010-01-01

53

ELECTROLYTIC MEMBRANE DIALYSIS FOR TREATING WASTEWATER STREAMS  

Energy Technology Data Exchange (ETDEWEB)

This project will determine whether electrolytic dialysis has promise in the separation of charged particles in an aqueous solution. The ability to selectively move ions from one aqueous solution to another through a semipermeable membrane will be studied as a function of emf, amperage, and particle electrical charge. The ions selected for the study are Cl{sup -} and SO{sub 4}{sup 2-}. These ions are of particular interest because of their electrical conduction properties in aqueous solution resulting with their association with the corrosive action of metals. The studies will be performed with commercial membranes on solutions prepared in the laboratory from reagent salts. pH adjustments will be made with dilute reagent acid and base. Specific objectives of the project include testing a selected membrane currently available for electrolytic dialysis, membrane resistance to extreme pH conditions, the effectiveness of ...

2000-04-01

54

Measurement of oxidation rate of sulfite in rain water in Yokohama, Japan  

Energy Technology Data Exchange (ETDEWEB)

In recent years, the influences of acid rain such as the acidification of lake water, on bio-system by the heavy metals from effluent of soils with acid rain and also on the structural materials of buildings are seriously discussed. Sulfur and nitrogen that are contained in fossil fuels are released into the atmosphere by the fuel combustion as their oxides dissolve in rain drops as sulfite and nitrous ions, where they are further oxidized into sulfate and nitrate ions These ions lower the pH of rain water resulting so-called acid rain. Therefore, it is important to accurately determine these ions in rain water for the investigation of reality of acid rain. However, it is not easy to accurately determine these ions, especially for sulfite ions in rain water, since they are quickly oxidized by the catalytic action of metallic ions such as ferric and manganous ions. And light, temperature, pH of solution and also species and concentrations of ...

1986-04-01

55

Enhancement of N-nitrosamine formation on granular-activated carbon from N-methylaniline and nitrite  

Energy Technology Data Exchange (ETDEWEB)

Sterile aqueous N-methylaniline solutions were allowed to equilibrate at various nitrite, F-400 granular-activated carbon, and pH levels for 1 week. The aqueous and activated carbon phases were extracted and analyzed for nitrosamines relative to an added internal standard. Selected ion monitoring GC/MS, utilizing continuous monitoring of the NO/sup +/ ion (m/z 29.9980) characteristic of nitrosamines, at medium resolution (R = 2500-3000) was applied to quantitatively measure nitrosamines at picograms per microliter concentrations. This method selected for nitrosamine products only and eliminated interferences from non-nitrosamine reaction products. Results indicate that the pressure of granular-activated carbon significantly enhanced the formation of nitrosamine from N-methyl-aniline (F = 145, P< 0.0001). The amount of N-nitrosomethylaniline formed in the presence of activated carbon was 75 times more than that formed in the absence of ...

1986-10-01

56

Chemical properties of positive singly charged astatine ion in aqueous solution  

Energy Technology Data Exchange (ETDEWEB)

The mobility of oxidized astatine in solutions H(Na)ClO/sub 4/ (..mu..=0.4M)-1.10/sup -4/M K/sub 2/Cr/sub 2/O/sub 7/ has been measured at 25 degC in the interval 0.63<=pH<=1.68. Under these conditions astatine migrates to the cathode only. The speeds of the migration depends upon the concentration of hydrogen ions in solutions are: pH 1.68 Usub(c)=1.17.10/sup -4/ cm/sup 2/ V/sup -1/ s/sup -1/; pH 0.63 Usub(c)=2.67.10/sup -4/ cm/sup 2/ V/sup -1/ s/sup -1/. The effect agrees with the opinion that the singly charged cation of astatine formed in acidic solutions is a strong aquacomplex ((H/sub 2/O)sub(x)At)/sup +/ (x=1-2) (protonated hypoastatic acid). Deprotonation constant of this cation is Ksub(dp)=0.032+-0.005. Specific properties of the astatine cation are given. They can be explained, probably, through the peculiarities of its structure. 14 refs.

1984-08-01

57

Chemical properties of positive singly charged astatine ion in aqueous solution  

International Nuclear Information System (INIS)

The mobility of oxidized astatine in solutions H(Na)ClO_4 (#mu#=0.4M)-1.10"-"4M K_2Cr_2O_7 has been measured at 25 degC in the interval 0.63<=pH<=1.68. Under these conditions astatine migrates to the cathode only. The speeds of the migration depends upon the concentration of hydrogen ions in solutions are: pH 1.68 Usub(c)=1.17.10"-"4 cm"2 V"-"1 s"-"1; pH 0.63 Usub(c)=2.67.10"-"4 cm"2 V"-"1 s"-"1. The effect agrees with the opinion that the singly charged cation of astatine formed in acidic solutions is a strong aquacomplex [(H_2O)sub(x)At]"+ (x=1-2) (protonated hypoastatic acid). Deprotonation constant of this cation is Ksub(dp)=0.032+-0.005. Specific properties of the astatine cation are given. They can be explained, probably, through the peculiarities of its structure. (author).

58

Measuring equipment for the monitoring of air pollution control - a market review  

Energy Technology Data Exchange (ETDEWEB)

The paper abstracted gives a tabular survey of the suppliers and applications of measuring equipment. Equipment is available for the following fields of application: Continuous measuring instruments for stationary operation, laboratory equipment for sampling and hand equipment for mobile measurement, sampling equipment for examining emissions and gases, detectors, storage and evaluation equipment and meteorological instruments. (PW).

1986-01-01

59

Measurement of time of travel in streams by dye tracing  

Energy Technology Data Exchange (ETDEWEB)

The US Geological survey is active in measuring time of travel in streams using dye tracers. This manual describes methods of measuring time of travel of water and waterborne solutes by dye tracing. The fluorescent dyes, measuring equipment used, and field and laboratory procedures are also described. Methods of analysis and presentation to illustrate time of travel of streams are provided.

1989-01-01

60

Results of the Interlaboratory Exercise CSN/CIEMAT-100 Among Environmental Radioactivity Laboratories (Soil); Resultados del Ejercicio Interlaboratorios de Radiactividad Ambiental CSN/CIEMAT-00 (Suelo)  

Energy Technology Data Exchange (ETDEWEB)

The document describes the outcome of the CSN/CIEMAT-00 interlaboratory test comparison among environmental radioactivity laboratories. the exercise was organised according to the ISO-43 and the ISO/IUPAC/AOAC Harmonized Protocol for the proficiency testing of analytical laboratories. the test sample was a soil containing environmental levels of K-40, Ra-226, Ac-228, Sr-90, Cs-137, Cs-134, Pu (239-240) y Am-241. the Universidad Autonoma de Barcelona prepared the material and reported adequate statistical studies of homogeneity. The results of the exercise were computed for 30 participating laboratories, and their analytical performance was assessed using the u-score approach. A raised percentage of satisfactory laboratory performance has been obtained for all the analysis, being the best performance in gamma measurements. The exercise has drawn that several ...

2002-07-01

61

Selective detection of hexachromium ions by localized surface plasmon resonance measurements using gold nanoparticles/chitosan composite interfaces.  

Science.gov (United States)

Selective removal of hexavalent chromium ions from aqueous solutions using a chitosan/gold nanoparticles composite film was demonstrated. Localized surface plasmon resonance (LSPR) was used to measure the interface stability and detect the incorporation of chromium ions over time. The effects of pH, ethylenediaminetetraacetic acid (EDTA), and various foreign ions such as trivalent chromium, sodium, calcium, phosphate, sulfate and chloride on the adsorption of hexavalent chromium were investigated. PMID:19381379

2009-03-04

63

Exploiting unique germplasm resources of leguminous trees: Prosopis, leucaena and acacia. Final report, August 31, 1982-August 30, 1992  

Energy Technology Data Exchange (ETDEWEB)

In Haiti, and other semiarid regions of the world, the need for fuelwood and forage is critical. The report summarizes research conducted over a ten year period on developing replicable plantations of leguminous trees in semiarid lands, especially in areas near seawater salinity levels. Research included greenhouse and laboratory work followed by field trials in Haiti and focused on two species: Prosopis and Leucaena. (Acacia is mentioned in the report's title but not in the report itself.) Results were as follows. (1) Greenhouse experiments identified leaf diagnostic criteria indicating mineral nutrient deficiencies in field trees. It also established the importance of micronutrients, especially zinc, in permitting growth in high pH (9.0) soils.

1992-01-01

64

Automation in urinalysis: evaluation of three urine test strip analysers.  

Science.gov (United States)

A clinical laboratory evaluation was conducted on the Clinitek Auto 2000, the Super Aution Analyzer and the Urotron RL9 for the determination of glucose, protein, pH, blood, ketone-bodies and bilirubin.Precision of the systems was tested using three commercial control urine materials, and reported as the percentage of times the instrument repeats a certain value. Good repeatability was obtained with all the instruments.Accuracy of the systems was evaluated by comparison with quantitative procedures, and to check agreement between methods yielding semi-quantitative and quantitative results, ranges of acceptability were defined, based on the criteria reported in a previous paper [2]. It was then found that 87.5 to 98.9% of results from the Urotron RL9 and the Clinitek Auto 2000 were acceptable. With the Super Aution Analyzer the level of agreement was apparently lower because of the higher number of concentration steps used by this instrument. ...

1988-01-01

65

Optical properties of fly ash. Volume 2, Final report  

Energy Technology Data Exchange (ETDEWEB)

Research performed under this contract was divided into four tasks under the following headings: Task 1, Characterization of fly ash; Task 2, Measurements of the optical constants of slags; Task 3, Calculations of the radiant properties of fly ash dispersions; and Task 4, Measurements of the radiant properties of fly ash dispersions. Tasks 1 and 4 constituted the Ph.D. research topic of Sarbajit Ghosal, while Tasks 2 and 3 constituted the Ph.D. research topic of Jon Ebert. Together their doctoral dissertations give a complete account of the work performed. This final report, issued in two volumes consists of an executive summary of the whole program followed by the dissertation of Ghosal and Ebert. Volume 2 contains the dissertation of Ebert which covers the measurements of the optical constants of slags, and calculations of the radiant properties of fly ash dispersions. A list of ...

1994-12-01

66

Beam emittance measurements of ORNL negative ion sources  

Energy Technology Data Exchange (ETDEWEB)

The emittances of hydrogen and deuterium negative ion beams produced by volume ion sources have been measured in a transverse plane normal to the beam trajectory. The extraction voltage was varied from 10 to 40 kV, and the transverse magnetic field in the Penning discharges was varied from 0.1 to 0.2 T. Measurements were made on beams with current densities up to 60 mA/cm/sup 2/ at Oak Ridge National Laboratory with an emittance scanner originally developed at Los Alamos National Laboratory. The beam profile at the scanner can be used to improve the accuracy of the emittance measurements. Other factors affecting emittance measurements are discussed. This analysis may be applicable to other ion sources. 6 figs.

1989-01-01

67

HPA - Radon Calibration Facilities  

Wastenet

... Radon gas concentrations are measured using instruments with calibrations traceable to the UK National Physical Laboratory and PTB, Germany. The primary facility is a 43 m3 walk-in chamber accessed by an airlock. Radon gas is maintained at a level in this chamber that is ...

68

Oxidation inhibition of sulfite in dual alkali flue gas desulfurization system.  

Science.gov (United States)

A laboratory-scale well-mixed thermostatic reactor with continuously blasting air was used to investigate the oxidation inhibition of sulfite in dual alkali flue gas desulfurization (FGD) system. The effects of operating parameters such as pH value and catalyst concentration on the oxidation were studied. Sodium thiosulfate was used in the system, and was found that it significantly inhabited the sulfite oxidation. In the absence of catalyst, sodium thiosulfate at 12.67 mmol/L had an inhibition efficiency of approximately 98%. While in the presence of catalyst, sodium thiosulfate at 26.72 mmol/L had an inhibition efficiency less than 85.0%. The oxidation reaction order of sulfite in the sodium thiosulfate was determined to be -1.90 and -0.55 in the absence and presence of the catalyst, respectively. Apparent activation energy of oxidation inhibition was calculated to be 53.9 kJ/mol. Pilot tests showed that the consumption rate of thiosulfate ...

2007-01-01

69

Growth model and on-line measurement of pitting corrosion on carbon steel  

Energy Technology Data Exchange (ETDEWEB)

A growth model of pitting corrosion of carbon steel in cooling water systems was developed on microscopic observations of pits and electrochemical studies. Results of pitting corrosion measurements in laboratory and field conditions with the model, using a newly developed electrochemical device, are discussed. For an actual heat exchanger up to a year operation, the values of pitting depth estimated were in good agreement with the measured values.

1996-12-01

70

Mixed waste landfill corrective measures study final report Sandia National Laboratories, Albuquerque, New Mexico.  

Energy Technology Data Exchange (ETDEWEB)

The Mixed Waste Landfill occupies 2.6 acres in the north-central portion of Technical Area 3 at Sandia National Laboratories, Albuquerque, New Mexico. The landfill accepted low-level radioactive and mixed waste from March 1959 to December 1988. This report represents the Corrective Measures Study that has been conducted for the Mixed Waste Landfill. The purpose of the study was to identify, develop, and evaluate corrective measures alternatives and recommend the corrective measure(s) to be taken at the site. Based upon detailed evaluation and risk assessment using guidance provided by the U.S. Environmental Protection Agency and the New Mexico Environment Department, the U.S. Department of Energy and Sandia National Laboratories recommend that a vegetative soil cover be deployed as the preferred corrective measure for the Mixed Waste Landfill. The cover would be ...

2004-03-01

71

Realistic Earth matter effects and a method to measure small \\theta_{13} in the detection of supernova neutrinos  

CERN Document Server

In this paper, we first calculate the realistic Earth matter effects on the detection of type II supernova neutrinos at the Daya Bay reactor neutrino experiment which is currently under construction. It is found that the Earth matter effects depend on the neutrino incident angle \\theta, the neutrino mass hierarchy \\Delta m_{31}^{2}, the crossing probability at the high resonance region inside the supernova, P_H, the neutrino temperature, T_{\\alpha}, and the pinching parameter in the neutrino spectrum, \\eta_{\\alpha}. We give the expression for the dependence of P_H on the neutrino mixing angle \\theta_{13}. With this we obtain the relations between \\theta_{13} and the event numbers for various reaction channels of supernova neutrinos. Using these relations, we propose a possible way to measure \\theta_{13} smaller than 1.5^\\circ. Such a sensitivity cannot be achieved by the Daya Bay neutrino experiment (the ...

2008-01-01

72

( sup 14 C)-Sucrose uptake by guard cell protoplasts of pisum sativum, argenteum mutant  

Energy Technology Data Exchange (ETDEWEB)

Guard cells rely on import for their supply with reduced carbon. The authors tested by silicone oil centrifugation the ability of guard cell protoplasts to accumulated ({sup 14}C)-sucrose. Uptake rates were corrected after measurement of {sup 14}C-sorbitol and {sup 3}H{sub 2}O spaces. Sucrose uptake followed biphasic kinetics, with a high-affinity component below 1 mM external sucrose (apparent K{sub m} 0.8 mM at 25C) and a low-affinity nonsaturable component above. Uptake depended on pH (optimum at pH 5.0). Variations in the concentrations of external KCl, CCCP, and valinomycin indicated that about one-half of the sucrose uptake rate could be related to an electrochemical gradient across the plasmalemma. Total uptake rates measured at 5 mM external sucrose seem to be sufficient to replenish emptied plastids with starch within a few hours.

1991-05-01

73

The SUERC AMS laboratory after 3 years  

British Library Electronic Table of Contents (United Kingdom)

The new SUERC AMS Laboratory was described at AMS-9. Since then there have been technological developments, added and improved analysis capability, the formation of additional complementary groups, the purchase of another instrument, and many samples measured. Be, C, Al, Cl, Ca and I-AMS are established with measured species changing weekly. Full-terminal potential running is now routine and 5MV is proving sufficient for all species. Ion detection and evaluation has also been improved by the use of even thinner detector windows as necessary and a more powerful on-line data analysis system. Routine radiocarbon measurement is to 4permil reproducibility at middling current and graphite samples of as little as 100mg C can be accommodated. Even smaller samples can be measured as CO2 using He ca...

2007-01-01

74

Comparison of effectiveness of three radon detectors (LR115, CR39 and silicon diode pin) placed in a cylindrical device -theory and experimental techniques  

Energy Technology Data Exchange (ETDEWEB)

Researchers at the Laboratory of Nuclear Microanalysis in Besancon (France) are developing and improving radon measurements in order to detect and analyse, more precisely radon emanation anomalies in both fields of Earth Sciences and Radioprotection. In order to characterize radon emanation, two complementary techniques are developed; continuous measurement through a portable proportional counter and passive measurements by nuclear track detectors for both fieldwork and laboratory analysis. A mathematical model is being devised to interpret the nuclear track detector response. This model is performed according to the device characteristics: type of detectors, shape and size of cells and whether a membrane is used or not. In addition to the theoritical study, experimental radon concentration measurements will be reported. (author).

1993-12-31

75

Comparison of effectiveness of three radon detectors (LR115, CR39 and silicon diode pin) placed in a cylindrical device -theory and experimental techniques  

International Nuclear Information System (INIS)

Researchers at the Laboratory of Nuclear Microanalysis in Besancon (France) are developing and improving radon measurements in order to detect and analyse, more precisely radon emanation anomalies in both fields of Earth Sciences and Radioprotection. In order to characterize radon emanation, two complementary techniques are developed; continuous measurement through a portable proportional counter and passive measurements by nuclear track detectors for both fieldwork and laboratory analysis. A mathematical model is being devised to interpret the nuclear track detector response. This model is performed according to the device characteristics: type of detectors, shape and size of cells and whether a membrane is used or not. In addition to the theoritical study, experimental radon concentration measurements will be reported. (author).

76

Passivity of polycrystalline NiMnGa alloys for magnetic shape memory applications  

Energy Technology Data Exchange (ETDEWEB)

The corrosion and passivation behaviour of bulk polycrystalline martensite Ni{sub 50}Mn{sub 30}Ga{sub 20} and austenite Ni{sub 48}Mn{sub 30}Ga{sub 22} alloys was compared in electrolytes with different pH values. Linear anodic and cyclic potentiodynamic polarisation methods and anodic current transient measurements have been conducted for the alloys and their constituents to analyze free corrosion, anodic dissolution and passive layer formation processes. Electrochemically treated alloy surfaces were characterized with scanning electron microscopy (SEM) and angle-resolved x-ray photoelectron spectroscopy (XPS). The electrochemical response of both alloys is in principal similar and is dominated by the Ni oxidation. In acidic solutions (pH 0.5 and 5) a slightly higher reactivity is detectable for the martensitic alloy which is mainly attributed to enhanced dissolution processes at the multiple twin boundaries. In weakly ...

2009-05-15

77

Passivity of polycrystalline NiMnGa alloys for magnetic shape memory applications  

International Nuclear Information System (INIS)

The corrosion and passivation behaviour of bulk polycrystalline martensite Ni50Mn30Ga20 and austenite Ni48Mn30Ga22 alloys was compared in electrolytes with different pH values. Linear anodic and cyclic potentiodynamic polarisation methods and anodic current transient measurements have been conducted for the alloys and their constituents to analyze free corrosion, anodic dissolution and passive layer formation processes. Electrochemically treated alloy surfaces were characterized with scanning electron microscopy (SEM) and angle-resolved x-ray photoelectron spectroscopy (XPS). The electrochemical response of both alloys is in principal similar and is dominated by the Ni oxidation. In acidic solutions (pH 0.5 and 5) a slightly higher reactivity is detectable for the martensitic alloy which is mainly attributed to enhanced dissolution processes at the multiple twin boundaries. In weakly acidic to strongly alkaline solutions ...

2009-05-01

78

Mitochondrial sequestration of BCECF after ester loading in the giant alga Chara australis.  

Science.gov (United States)

Ratiometric fluorescent dyes are often used to monitor free ion concentrations in vivo, especially in cells that are recalcitrant to transformation with genetically encoded fluorescent markers. Although intracellular dye distributions are often found to be cytosolic, dye localisation has often not been examined in detail. We began exploring the use of BCECF (2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein) to monitor pH in the giant alga Chara australis and discovered that younger leaf cells could be loaded using the acetoxymethyl ester of BCECF. However, we were puzzled to find in microphotometric measurements that the fluorescence ratio appeared insensitive to manipulations affecting cytosolic pH. Confocal imaging of C. australis cells loaded with BCECF showed an accumulation of the dye in two locations: (1) on the outside of the chloroplasts in irregularly shaped stationary bodies; (2) within 1-1.5 mum structures that ...

2007-12-19

79

Effective laser luminescence of nanocomposites Eu(TTA)2(Ph3PO)2NO3-polyvinylpyrrolidone  

International Nuclear Information System (INIS)

Thin films (1-10 ?m thickness) of nanocomposites (NC) based on organic coordinated compound (OCC) Eu(TTA)2(Ph3PO)2NO3 (where TTA is thenoyl trifluoroacetonate (C8H5F3O2S), Ph3PO - triphenylphosphine (C6H5PO) and polymer-polyvinylpyrrolidone ((C6H9NO)n) (PVP)) were obtained by chemical methods and with different molar ratios into organic polymer matrix. NC have been characterized by measurements of optical transmission, excitation spectra of photoluminescence (PL) and photoluminescence of NC at different concentrations of Eu(TTA)2(Ph3PO)2NO3 in NC. In the optical transmission of NC, the characteristic parameters of NC such as threshold absorbance, dependence on the concentration of the organic coordinated compound in NC, etc., have been determined The displacement of threshold absorption to infrared is observed with increasing of the concentration of the coordination material in NC. The excitation ...

2011-07-07

80

The ''Complex Reality'' of Research Capacity Development in Mathematics Education in Southern African Development Community Countries  

Science.gov (United States)

This paper explores how an aid-funded Ph.D.-programme in mathematics education instituted in some Southern African Development Community countries measures up to issues related to research capacity development projects. The research capacity development programme is described and reflected against mutual benefit, relevance, sustainability and prioritization of the location of project funding expenditure--some of the constructs in the discourse on research capacity development initiatives. It is found that the benefits of the programme are indeed mutual; the outcomes regarding relevance and sustainability are more uncertain and the location of expenditure of the funding is not overtly in favour of the donor country.

2005-11-01

81

Pitting corrosion of zirconium and hafnium  

Energy Technology Data Exchange (ETDEWEB)

The initiation and inhibition of pitting corrosion on zirconium and hafnium in aqueous solutions have been investigated by potentiodynamic, potentiostatic and galvanostatic measurements at 25/sup 0/C. Effects of Cl/sup -/, Br/sup -/and I/sup -/ have been examined over a range of salt concentrations and pH. All three halide ions cause pitting attack on the two metals, but this may be inhibited by other anions. The results show that hafnium is more easily protected against pitting than is zirconium. The data are treated by the Butler-Volmer equation to yield more information about the mechanisms of the pitting corrosion.

1988-02-01

82

Enhancement of the absorption of CO{sub 2} in alkaline buffer solutions: Joint action of two enhancers  

Energy Technology Data Exchange (ETDEWEB)

The authors measured the absorption of CO{sub 2} in alkaline 0.5 M/0.5 M sodium carbonate/bicarbonate buffers containing either saccharose and sodium arsenite or saccharose and formaldehyde. Absorption enhancement increased upon increasing the concentration of either of the catalysts, but the joint action of the two was always less than the sum of their individual effects, the difference being a function of the acidities and concentrations of the catalysts and the pH of the carbonate/bicarbonate buffer solution

1999-05-01

83

Conductivity and Viscosity Measurements for Binary Lysozyme Chloride Aqueous Solution and Ternary Lysozyme-Salt-Water Solution  

CERN Document Server

We use the conductimetric method, adequate to electrolytes, to determine the lysozyme charge in lys-water and ternary lys-salt-water systems. We measured also the viscosities for the above binary and ternary systems in the same conditions at pH$=4.5$ and T$=298$ K, measurements that allow us to see any effect of viscosity on cations mobilities and implicitly on the lysozyme charge. The method is illustrated for the lysozyme chloride aqueous solution system at 25$^o$ C, using the data reported here for pH$=4.5$ at 0.15, 0.6, 0.8, 1., 1.5, 2., 2.5, 3., 3.5 mM (mg/mL) lysozyme chloride concentrations. The method was also applied to ternary lys-salt-water systems in the same conditions at pH$=4.5$ and T$=25^o$ C. Ternary conductivities are reported for a mean concentration 0.6 mM of lysozyme chloride in all systems and a mean concentration 0.01, 0.025, 0.05, 0.1, 0.175, 0.2, 0.5, 0.7, ...

2004-01-01

84

FY 1992 Measurements and Characterization Branch annual report  

Energy Technology Data Exchange (ETDEWEB)

The Measurements and Characterization Branch actively supports the advancement of DOE/NREL goals for the development and implementation of the solar photovoltaic (PV) technology. The primary focus of the laboratories is to provide state-of-the-art analytical capabilities for materials and device characterization and fabrication. The branch houses a comprehensive facility that Is capable of providing information on the full range of PV components. A major objective of the branch is to aggressively pursue collaborative research with other government laboratories, universities, and industrial firms for the advancement of Pv technologies. Members of the branch disseminate research findings to the technical community in publications and presentations. The Measurements and Characterization Branch encompasses seven coordinated research groups, providing integrated research and development that covers all ...

1993-03-01

85

Intercomparison of irradiance measurements based on WRR and ETL irradiance scales  

Energy Technology Data Exchange (ETDEWEB)

We report the corrected intercomparison of the World Radiometer Reference (WRR) irradiance scale and the Electrotechnical Laboratory (ETL) spectral irradiance scale. In addition, we confirm the intercomparison precision using the test facility where the irradiance of ETL 500 W standard lamp can be measured directly with the cavity radiometer. The results showed that the irradiance based on the WRR scale was 0.5-0.7% lower than the one based on the ETL scale

1997-10-14

86

Development of a real-time, neutron and gamma dosimeter  

Energy Technology Data Exchange (ETDEWEB)

In 1998, research began at Idaho National Engineering and Environmental Laboratory to investigate the application of {sup 6}Li and {sup 7}Li isotopes to the measurement of neutron and gamma radiation. Various size pairs of {sup 6}Li and {sup 7}Li based detectors were exposed to mixed neutron and gamma radiation. Experiments demonstrated that these detectors could be used to measure low level neutron radiation in the presence of high level gamma radiation. (author)

2001-07-01

87

Development of a real-time, neutron and gamma dosimeter  

International Nuclear Information System (INIS)

In 1998, research began at Idaho National Engineering and Environmental Laboratory to investigate the application of "6Li and "7Li isotopes to the measurement of neutron and gamma radiation. Various size pairs of "6Li and "7Li based detectors were exposed to mixed neutron and gamma radiation. Experiments demonstrated that these detectors could be used to measure low level neutron radiation in the presence of high level gamma radiation. (author)

2001-06-10

88

A novel fluorescent pH probe for expression in plants  

UK PubMed Central (United Kingdom)

BackgroundThe pH is an important parameter controlling many metabolic and signalling pathways in living cells. Recombinant fluorescent pH indicators (pHluorins) have come into vogue...Full Text Available

89

Study of passive films formed on AISI 304 stainless steel by impedance measurements and photoelectrochemistry  

Energy Technology Data Exchange (ETDEWEB)

Moss-Schottky plots and photoelectrochemical measurements were made on films formed at different potentials on AISI 304 stainless steel in a borate/boric acid solution, pH 9.2. The results allowed the determination of the semiconductive properties and band structure of the films, which account for the existence of two kinds of films depending on the formation potential. For potentials below 0 V (SCE), the results point out for a film with an inverse spinel structure constituted by Cr-substituted magnetite with two donor levels. Above 0 V only one donor level is detected, which should be Fe{sup 2 +} on tetrahedral sites.

1990-01-01

90

Study of passive films formed on AISI 304 stainless steel by impedance measurements and photoelectrochemistry  

International Nuclear Information System (INIS)

Moss-Schottky plots and photoelectrochemical measurements were made on films formed at different potentials on AISI 304 stainless steel in a borate/boric acid solution, pH 9.2. The results allowed the determination of the semiconductive properties and band structure of the films, which account for the existence of two kinds of films depending on the formation potential. For potentials below 0 V (SCE), the results point out for a film with an inverse spinel structure constituted by Cr-substituted magnetite with two donor levels. Above 0 V only one donor level is detected, which should be Fe"2 "+ on tetrahedral sites.

1990-01-01

91

Chemical, electrical and electrochemical characterization of hybrid organic/inorganic polypyrrole/PW12O40^3^- coating deposited on polyester fabrics  

British Library Electronic Table of Contents (United Kingdom)

A study of the stability of conducting fabrics of polyester (PES) coated with polypyrrole/PW12O40^3^- (organic/inorganic hybrid material) in different pH solutions (1, 7, 13) has been done. Washing tests were also done in views of its possible application in electronic textiles such as antistatic clothing. X-ray photoelectron spectroscopy (XPS) studies have been done to quantify the amount of counter ion that remains in the polymer matrix and determine the doping ratio (N^+/N) after the different tests. Scanning electron microscopy (SEM) was also used to observe morphological differences after the different tests. Surface resistivity changes were measured by means of electrochemical impedance spectroscopy (EIS). Scanning electrochemical microscopy (SECM) was employed to measure changes in ...

2011-01-01

92

Chemical transformations of organic matter during the composting of wood industry wastes (residues); Transformacoes quimicas da materia organica durante a compostagem de residuos da industria madeireira  

Energy Technology Data Exchange (ETDEWEB)

Composting of sawdust and paper mill sludge, using a 'Kneer' process reactor, was studied in an attempt to elaborate upon organic matter transformation during the process and to define parameters to measure the compost maturity level. Temperature, electron paramagnetic resonance data, ash and C, H, N and S contents, and a spectroscopic method using ultraviolet-visible (UV-VIS) for alkaline (pH = 8.5) and solid samples was used to study the maturity of the compost samples. These parameters were measured in 6 humic acids extracted from the compost samples during 29 days. The results of this work show that the 'Kneer' process is efficient in transforming ligno-celulitic residues in a short time (29 days), into an organic fertilizer material with application perspectives (author)

2004-06-01

93

Accelerated aging corrosion tests for buried metal structures  

Energy Technology Data Exchange (ETDEWEB)

It is necessary to identify those measurable soil parameters which dictate the severity of the corrosion problem for coated irons and steels. When this is done, meaningful accelerated aging tests can be designed to validate the reduced corrosion rate for the planned coating. The following discussion introduces the important concepts and measurement parameters in the (a) design of accelerated aging tests, and (b) evaluation of the planned installation site for corrosion potential. Certain combinations of soil oxidation reduction potential (ORP) or electric potential (Eh), acidity (pH), fertilizer, water table, and soil hydraulic conductivity can result in severe corrosion of buried steel/iron vessels. If there are power lines nearby, additional loss of vessel material to the soil will occur. These factors are discussed.

1996-10-01

94

The application of high pH operation to the secondary water chemistry at Genkai Nuclear Power Station  

International Nuclear Information System (INIS)

PWR plants have made efforts to maintain the long-term integrity of the steam generators (SG) by reducing the amount of corrosion products entering the secondary side of the SG. Iron entered the SG can cause several problems: degraded heat conductivity of the SG tubes in locations where iron is deposited, water level oscillations in the SG due to tube support plate hole blockage, and initiation and propagation of inter-granular attacks (IGA) and stress corrosion cracking (SCC). One of the most effective measures, high all-volatile treatment (AVT) chemistry has been applied to actual plants to reduce the flow-accelerated corrosion (FAC) coming from the carbon steel piping. The secondary water chemistry at Genkai NPS 1 and 2 changed, from the Low AVT chemistry to the High AVT chemistry, in November 2006. In this paper, we will describe the results of experiments in applying the use of High pH water in the secondary water system at Genkai NPS. ...

2009-02-01

95

Synthesis and characterization of diastereomeric (substituted iminodiacetato)(1,2-diaminocyclohexane)platinum(II) complexes  

Energy Technology Data Exchange (ETDEWEB)

Novel complexes of the type (Pt(DACH)(N-R-iminodiacetate)), wherein DACH represents (R,S)- and (R,R)-1,2 diaminocyclohexane and R represents /minus/Me, /minus/EtOH, and /minus/CH/sub 2/Ph groups, have been prepared, purified, and characterized by spectroscopic techniques (/sup 1/H, /sup 13/C, and /sup 195/Pt NMR;MS(FAB);IR) and by the measurement of selected physical properties (pH, pK/sub a/, conductivity, and molecular weights). The data are consistent with the formation of two diastereomeric complexes in unequal proportions in which the N-R-iminodiacetate ligand appears to be bonded as a pseudofacial tridentate chelate. One are of the ligand forms a stable five-membered-ring O,N-chelate while the other arm appears to be involved in ion-pair formation (zwitterion-like) involving the carboxylate anion and the formally positive Pt(II) central metal atom. It has been demonstrated indirectly that an active impurity was ...

1988-11-16

96

Studies on accumulation of uranium by fungus Lentinus sajor-caju  

Energy Technology Data Exchange (ETDEWEB)

The untreated, heat- and alkali-treated Lentinus sajor-caju mycelia were used for the recovery of uranium from aqueous solutions. The effect of pH, temperature, initial concentration of UO{sub 2} {sup 2+} ions and contact time parameters were investigated in a batch system. The particles sizes of the fungal mycelia were ranging from 100 to 200 {mu}m. Biosorption equilibriums were established in about 30 min and the correlation regression coefficients show that the adsorption process can be well defined by the Freundlich equation. The alkali treated form had a high biosorption capacity (378 mg/g) than those of the untreated (268 mg/g) and heat-treated fungal mycelia (342 mg/g). Optimum biosorption was observed at pH 4.5 for all the tested fungal preparations and was independent of temperature (5-35 deg. C). In addition, the polarity and surface energy of the fungal biomass film preparations were determined by contact angle ...

2006-08-21

97

Pitting corrosion of Alloy 690 in thiosulfate-containing chloride solutions  

Energy Technology Data Exchange (ETDEWEB)

The effects of thiosulfate ion and solution pH on pitting corrosion of Alloy 690 in chloride solution were explored. Potentiodynamic polarization measurements were conducted to evaluate pitting corrosion susceptibility of Alloy 690 in these environments. The results showed that pitting corrosion occurred in the mill-annealed (1050 deg. C/5min) Alloy 690 in 1 wt% NaCl solution but not in 0.1 M Na{sub 2}S{sub 2}O{sub 3} solution. The value of pitting nucleation potential (E{sub np}) determined in 1 wt% NaCl solution (without Na{sub 2}S{sub 2}O{sub 3} ) increased with increasing solution pH value in the range of 2-10. The addition of Na{sub 2}S{sub 2}O{sub 3} to 1 wt% NaCl solution greatly affected the pitting corrosion behavior, which was dependent on concentration. The preformed nickel sulfide surface film due to the presence of Na{sub 2}S{sub 2}O{sub 3} caused Alloy 690 to become more susceptible to pitting corrosion in 1 ...

2000-02-01

98

Evaluation of heterogeneity in thickness of passive films on pure iron by scanning electrochemical microscopy  

Energy Technology Data Exchange (ETDEWEB)

Scanning electrochemical microscopy (SECM) was applied to evaluate the heterogeneity of a passive film formed on a pure iron electrode in deaerated pH 8.4 borate solution. A probe current image of SECM was measured with a tip-generation/sub-strate-collection (TO/SC) mode in deaerated pH 8.4 borate solution containing 0.03 moldm{sup -3} Fe(CN){sub 6}{sup 4-} as a mediator. The difference in thickness of passive films formed on two iron plates at different potentials could be evaluated from the probe current image. The probe current image of the passivated iron surface with distinctive crystal grains was composed of the patch patterns, the shapes of which coincided completely with the shapes of the substrate crystal grains. The probe current flowed above the grain surface oriented to {l_brace}100{r_brace} plane was less than that above the grain surface oriented to {l_brace}110{r_brace} or {l_brace}111{r_brace} plane. The ...

1999-04-01

99

Characterisation of passive films formed on low carbon steel in borate buffer solution (pH 9.2) by electrochemical impedance spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The comprehension of passivity and its protective character against corrosion is closely connected with the electronic properties of passive films. Passive films formed anodically on carbon steel in borate/boric acid solution, pH 9.2, have been characterised by electrochemical impedance spectroscopy (EIS). Mott-Schottky plots and impedance measurements were made on films formed at different potentials and times. The investigation allowed the determination of the semiconductive properties of the films. The results of the capacitance response indicate that the passive films behave like highly doped n-type semiconductors, showing that the passive film properties are dominated by iron. The value of donors density (N {sub D}) for the passive film is of the order of 10{sup 21} cm{sup -3} and decreases with increasing formation time and potential, indicating that defects decrease with increasing film thickness. Based on the information about the ...

2005-12-15

100

Characterisation of passive films formed on low carbon steel in borate buffer solution (pH 9.2) by electrochemical impedance spectroscopy  

International Nuclear Information System (INIS)

The comprehension of passivity and its protective character against corrosion is closely connected with the electronic properties of passive films. Passive films formed anodically on carbon steel in borate/boric acid solution, pH 9.2, have been characterised by electrochemical impedance spectroscopy (EIS). Mott-Schottky plots and impedance measurements were made on films formed at different potentials and times. The investigation allowed the determination of the semiconductive properties of the films. The results of the capacitance response indicate that the passive films behave like highly doped n-type semiconductors, showing that the passive film properties are dominated by iron. The value of donors density (N _D) for the passive film is of the order of 10"2"1 cm"-"3 and decreases with increasing formation time and potential, indicating that defects decrease with increasing film thickness. Based on the information about the physical ...

2005-12-15

101

Boiler and HRSG tube failures. Lesson 2. Corrosion fatigue  

Energy Technology Data Exchange (ETDEWEB)

Fatigue damage occurs in general when a boiler tube is subject to repeat cyclic or fluctuating loading although the stress produced is below the material yield strength. The types of fatigue damage include, e.g., corrosion, thermal, mechanical, vibration, and creep fatigue. It is important to determine which form of fatigue is active, because measures to avoid repeat failures differ as the case arises. In this lesson, the focus is exclusively on corrosion fatigue. Corrosion fatigue occurs by the combined synergistic actions of cyclic loading and a corrosive environment. It is a discontinuous process with crack initiation and growth during transient periods. The excessive stresses may be caused during boiler operation by the restraint at tube attachments and by load changes (in particular during cold starts or forced cools) or during shutdown or restart of circulation boilers by thermal stratification of water along the tube length. Poor water chemistry and its ...

2009-10-15

102

Laboratory evaluation of the hazard to wood mice, Apodemus sylvaticus, from the agricultural use of methiocarb molluscicide pellets  

Energy Technology Data Exchange (ETDEWEB)

Laboratory studies have been carried out to determine the toxicity of methiocarb pellets to wild trapped wood mice in order to provide some background data prior to any further evaluation of hazard in the field. In this study, wood mice were exposed to dry and to dampened methiocarb pellets in order to reproduce field trial application conditions. Field observations of methiocarb pellets indicate that the physical character changes under dry and wet weather conditions. This may affect their relative attractiveness and potential toxicity to wood mice. The laboratory assessment of exposed wood mice included measurement of brain esterase activities, methiocarb residues in selected mouse tissue, carcasses, and histological evaluation of kidney, liver and lungs.

1988-01-01

103

Gases in insulating oil - analysis of dissolved gases using a portable chromatograph  

Energy Technology Data Exchange (ETDEWEB)

New technological advances make it possible to perform on site gas-in-oil analysis quickly and efficiently. Gas-in-oil analysis is crucial in assessing the status of oil-filled electrical equipment. The new technique is used for extracting and measuring gases dissolved in electrical insulating oil. On-site sampling requires the use of a specially designed 100 ml capacity syringe. Extraction of the dissolved gases is made with a precise ratio of oil to air. A comparison was made between the analysis of the on-site and the laboratory techniques. Results showed that the detection limits of the on-site technique were comparable to those obtained by laboratory methods.

1996-07-01

104

Electromagnetic coupling of high-altitude, nuclear electromagnetic pulses  

International Nuclear Information System (INIS)

We have used scale models to measure the predicted coupling of electromagnetic fields simulating the effects of high-altitude nuclear electromagnetic pulses (HEMP) on the interior surfaces of electronic components. Predictive tools for exterior coupling are adequate. For interior coupling, however, such tools are in their infancy. Our methodological approach combines analytical, computational, and laboratory techniques in a complementary way to take advantage of their separate strengths. Computer models are a promising tool, as they can be used to treat complex objects with arbitrary shapes, dielectrics, and cables, and multiple apertures. Laboratory tests can expand the domain of investigation even further.

1984-11-01

105

Electrochemical properties of passive films on 440C stainless steel. Ph. D. Thesis  

Energy Technology Data Exchange (ETDEWEB)

Type 440C stainless steel is a high-C, high-Cr martensitic steel used in applications requiring high hardness and wear resistance in combination with moderate corrosion resistance. Typical applications include precision aerospace bearings and critical components in computer disk drives. The properties of passive films formed on 440C steel were investigated using advanced electrochemical techniques with a view to establishing a method to measure film stability directly in the passivation baths. Electrochemical measurements were sensitive to the passive film properties and were able to quantify the effect of cooling rate on passive film stability. The techniques used included linear polarization, AC impedance, small amplitude cyclic voltammetry, and coulostatic transient measurements. These provided results that exhibited excellent agreement with the AC impedance technique providing the most information about the interfacial ...

1990-10-01

106

Development of low-level liquid-waste treatment systems: April-September 1982  

Energy Technology Data Exchange (ETDEWEB)

A preliminary investigation was conducted on ion specific membranes. This investigation concentrated on testing candidate organic compounds for transporting cesium ions through a membrane composed of the organic compound supported on a substrate. Solid PVC membranes were initially tried, but were found to be too slow. Thereafter, only liquid membranes were tested. These were faster and cesium concentration factors up to 2.96 were achieved in a single membrane cell. A cell with two membranes achieved a cesium concentration factor of 4.19. Cesium precipitation with sodium tetraphenyl borate in high sodium concentrations was explored. No interference from sodium was found until the sodium nitrite concentration reached 4.5 moles. Concurrently, cesium concentrations as high as 5.4 g/L were precipitated. Potassium tetraphenyl borate is being investigated for use in exchange columns for the removal of cesium from solutions. Initial investigations show that cesium removal is affected by (K/sup ...

1982-12-22

107

Development of low-level liquid-waste treatment systems: April-September 1982  

International Nuclear Information System (INIS)

A preliminary investigation was conducted on ion specific membranes. This investigation concentrated on testing candidate organic compounds for transporting cesium ions through a membrane composed of the organic compound supported on a substrate. Solid PVC membranes were initially tried, but were found to be too slow. Thereafter, only liquid membranes were tested. These were faster and cesium concentration factors up to 2.96 were achieved in a single membrane cell. A cell with two membranes achieved a cesium concentration factor of 4.19. Cesium precipitation with sodium tetraphenyl borate in high sodium concentrations was explored. No interference from sodium was found until the sodium nitrite concentration reached 4.5 moles. Concurrently, cesium concentrations as high as 5.4 g/L were precipitated. Potassium tetraphenyl borate is being investigated for use in exchange columns for the removal of cesium from solutions. Initial investigations show that cesium removal is affected by [K"+] ...

108

Decontamination of LRW of low and intermediate level of activity with a new bio-sorbent mycoton  

International Nuclear Information System (INIS)

An absorption method of elimination of liquid radioactive wastes (LRW) of low and intermediate activity level by decreasing their contamination up to the level permitting their discharge into the environment is proposed in the paper. The LRW decontamination is accompanied with efficient compacting the resulting secondary solid wastes. The method is based on the use of a new very efficient, chitin containing natural fiber bio-sorbent, Mycoton, which is manufactured commercially in Ukraine. The chemical composition of the sorbent and its highly developed surface provide practically unrestricted opportunities for producing its modifications having any necessary absorption and operational characteristics. The effects of pH, the presence of various salts and complexing agents, as well as of some other factors to the distribution coefficients of the most important radionuclides have been carefully studied in experiments with Mycoton and its modifications. It appeared, ...

2005-10-09

109

Effects of oxygen, copper and acid chlorides on denting corrosion  

Energy Technology Data Exchange (ETDEWEB)

The effect of dissolved oxygen and copper on denting corrosion at 280/sup 0/C in solutions of NaCl at pH 9 with ammonia was investigated using a packed tube/support plate crevice in a laboratory simulation. The onset of corrosion was detected with a hydrogen analyzer sensitive to 0.2 ppB. In the absence of copper, rapidly rising hydrogen concentrations were detected only when the product of the chloride and oxygen concentrations were detected only when the product of the chloride and oxygen concentrations in the boiler-water exceeded 25 (ppM)/sup 2/, but at these high concentrations, unheated low-carbon steel surfaces in the system were as sensitive to corrosion as the heated crevice. When copper metal was present in the feed system, corrosion of the heated crevice occurred in the absence of oxygen, provided the copper had previously been exposed to dissolved oxygen. Dosing hydrazine into the feedwater eventually suppressed the ability of ...

1986-07-01

110

Design of pilot-scale constructed wetlands for tertiary treatment of refinery effluent  

Energy Technology Data Exchange (ETDEWEB)

Two pilot-scale constructed wetlands (4:1 length:width aspect) were designed for tertiary treatment of refinery effluent. As requirements for removal of contaminants from NPDES effluents become more stringent, cost-effective technological approaches are needed to achieve the necessary treatment levels and be efficient, effective and low maintenance. The fundamental design of these constructed wetlands was based on biogeochemical principles that regulate the fate and persistence of the targeted elements (Cu, Zn, Pb). In order to maximize opportunities to learn more about the internal function of the wetlands, they were built to operate in series or in parallel permitting hydraulic retention times of 24 to 48 hours. The wetlands were lined with {approximately}76 cm of compacted clay as well as a 30 mil polyethylene liner. The hydrosoil selected for use in the constructed wetlands is 74.1% sand, 25.6% silt, 0.3% clay. Based on laboratory studies, this hydrosoil ...

1994-12-31

111

Correlated charge-changing ion-atom collisions. Progress report, February 16, 1990--February 15, 1993  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the progress and accomplishments in accelerator atomic physics research supported by DOE grant DE-FG02-87ER13778 from February 16, 1990 through February 15, 1993. This work involves the experimental investigation of atomic interactions in collisions of charged projectiles with neutral targets or electrons, with particular emphasis on two-electron interactions and electron-correlation effects. The processes studied are of interest both from fundamental and applied points of view. In the latter case, results are obtained which are relevant to the understanding of laboratory and astrophysical plasmas, highly-excited (Rydberg) and continuum states of atoms and ions, atomic structure effects, the interaction of ions with surfaces, and the development of heavy-ion storage-rings. The results obtained have provided the basis for several M.A. thesis projects at Western Michigan and several Ph.D. dissertation projects are currently ...

1993-02-01

112

Chemical neutralization to control denting in nuclear steam generators  

International Nuclear Information System (INIS)

Laboratory testing at Combustion Engineering has indicated promise in controlling simulated steam generator tube denting through chemical neutralization. Testing was limited to on-line treatment, and two neutralizers have been evaluated: calcium hydroxide and boric acid. On-line treatment with calcium hydroxide successfully halted active denting whenever the bulk calcium concentration (in ppm) equaled or exceeded the bulk chloride concentration (in ppm). Calcium hydroxide also was effective as an alternative to ammonia as a pH controlling agent in two tests conducted without ingress of chloride. On-line treatment with boric acid consisted of a four-day soak at simulated low (approximately 30 percent) power with 50 ppm B followed by one month full-power operation with 10 ppm B. This treatment also halted denting. Nondestructive and destructive examination of test boilers gave no indication of adverse side effects associated with either ...

113

Response of a non-Hodgkin lymphoma to "6"0Co therapy monitored by 31P MRS in situ  

International Nuclear Information System (INIS)

High quality "3"1P MR spectra (signal to noise ratio (S/N) approximately 18, 15 min acquisition for each spectrum) were consistently obtained with surface coils over a period of 6-week RT. Both transient and steady state alterations in metabolites in response to RT were found in this case. The transient changes occurred during the first 3 hr immediately after the 3rd fractionated RT, these changes include the transient elevation of the PCr resonance, a decrease in PDE and an increase in intracellular pH. The monitoring showed that the metabolites approached steady state approximately 2 hr after the fractionated radiation intervention, suggesting that in vivo MRS can be useful for studying the dynamics of tumor response to RT such as repair of potential lethal damage, growth delay, and reoxygenation etc. The steady-state MR spectra showed the net response to each intervention and can clinically be useful for predicting and measuring the result ...

114

In vitro comparison of rat and chicken brain neurotoxic esterase  

Energy Technology Data Exchange (ETDEWEB)

A systematic comparison was undertaken to characterize neurotoxic esterase (NTE) from rat and chicken brain in terms of inhibitor sensitivities, pH optima, and molecular weights. Paraoxon titration of phenyl valerate (PV)-hydrolyzing carboxylesterases showed that rat esterases were more sensitive than chicken to paraoxon inhibition at concentrations less than or equal to microM and superimposable with chicken esterases at concentrations of 2.5-1000 microM. Mipafox titration of the paraoxon-resistant esterases at a fixed paraoxon concentration of 100 microM (mipafox concentration: 0-1000 microM) resulted in a mipafox I50 of 7.3 microM for chicken brain NTE and 11.6 microM for rat brain NTE. NTE (i.e., paraoxon-resistant, mipafox-sensitive esterase activity) comprised 80% of chicken and 60% of rat brain paraoxon-resistant activity with the specific activity of chicken brain NTE approximately twice that of rat brain NTE. The pH maxima for NTE from ...

1986-04-01

115

Effect of steric hindrance on carbon dioxide absorption into new amine solutions. Thermodynamic and spectroscopic verification through solubility and NMR analysis  

Energy Technology Data Exchange (ETDEWEB)

Aqueous solutions of 2-amino-2-hydroxymethyl-1,3-propanediol (AHPD), a sterically hindered amine, was examined as a potential CO{sub 2} absorbent and compared with the most commonly used absorbent, monoethanolamine (MEA) solution, through equilibrium solubility measurements and {sup 13}C NMR spectroscopic analyses. The solubilities of CO{sub 2} in aqueous 10 mass % AHPD solutions were higher than those in aqueous 10 mass% MEA solutions above 4 kPa at 298.15 K, but lower below 4 kPa. The solubility difference between these two solutions increased with the CO{sub 2} partial pressures above the crossover pressure. Equilibrated CO{sub 2}-MEA-H{sub 2}O and CO{sub 2}-AHPD-H{sub 2} solutions at various CO{sub 2} partial pressures ranging from 0.01 to 3000 kPa were analyzed by {sup 13}C NMR spectroscopy. AHPD contains more hydroxyl groups than nonhindered MEA, and hence the chemical shifts in its {sup 13}C NMR spectra were strongly influenced by the solution ...

2003-04-15

116

Use of portable HPGE detector and multichannel analyzer for in-situ gamma spectrometry of soil  

International Nuclear Information System (INIS)

Measurement of fission and activation products in the soil or over a plane grass land of a nuclear power station environment is required to find out the long term changes. The inventory of radionuclides in the soil is routinely determined by soil sampling, processing and gamma spectrometry in the laboratory. The method although is proven and accurate is time consuming and largely dependent on homogenous distribution. Therefore, an alternative and rapid method of in-situ gamma spectrometry using portable devices was standardized to determine the concentration of radionuclides in soil, for regular environmental monitoring as well as during emergency condition. The paper presents the methodology, ready to use factors and compares the results of a few measurements made in the environment of Tarapur Atomic Power Station by both in-situ and laboratory methods. (author)

2005-11-23

117

Sample requirements and design of an inter-laboratory trial for radiocarbon laboratories  

International Nuclear Information System (INIS)

An on-going inter-comparison programme which is focused on assessing and establishing consensus protocols to be applied in the identification, selection and sub-sampling of materials for subsequent "1"4C analysis is described. The outcome of the programme will provide a detailed quantification of the uncertainties associated with "1"4C measurements including the issues of accuracy and precision. Such projects have become recognised as a fundamental aspect of continuing laboratory quality assurance schemes, providing a mechanism for the harmonisation of measurements and for demonstrating the traceability of results. The design of this study and its rationale are described. In summary, a suite of core samples has been defined which will be made available to both AMS and radiometric laboratories. These core materials are representative of routinely dated material and their ages span the full range of the ...

2000-10-01

118

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

Energy Technology Data Exchange (ETDEWEB)

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

1989-08-01

119

Developement of the method for realization of spectral irradiance scale featuring system of spectral comparisons  

Energy Technology Data Exchange (ETDEWEB)

Realization of the scale of spectral responsivity of the detectors in the Directorate of Measures and Precious Metals (DMDM) is based on silicon detectors traceable to LNE-INM. In order to realize the unit of spectral irradiance in the laboratory for photometry and radiometry of the Bureau of Measures and Precious Metals, the new method based on the calibration of the spectroradiometer by comparison with standard detector has been established. The development of the method included realization of the System of Spectral Comparisons (SSC), together with the detector spectral responsivity calibrations by means of a primary spectrophotometric system. The linearity testing and stray light analysis were preformed to characterize the spectroradiometer. Measurement of aperture diameter and calibration of transimpedance amplifier were part of the overall experiment. In this paper, the developed method is ...

2010-10-15

120

Developement of the method for realization of spectral irradiance scale featuring system of spectral comparisons  

International Nuclear Information System (INIS)

Realization of the scale of spectral responsivity of the detectors in the Directorate of Measures and Precious Metals (DMDM) is based on silicon detectors traceable to LNE-INM. In order to realize the unit of spectral irradiance in the laboratory for photometry and radiometry of the Bureau of Measures and Precious Metals, the new method based on the calibration of the spectroradiometer by comparison with standard detector has been established. The development of the method included realization of the System of Spectral Comparisons (SSC), together with the detector spectral responsivity calibrations by means of a primary spectrophotometric system. The linearity testing and stray light analysis were preformed to characterize the spectroradiometer. Measurement of aperture diameter and calibration of transimpedance amplifier were part of the overall experiment. In this paper, the developed method is ...

2010-10-01

121

Laboratory differential simulation design method of pressure absorbers for carbonization of phenolate solution by carbon dioxide in coal-tar processing  

Energy Technology Data Exchange (ETDEWEB)

A laboratory differential simulation method is used for the design of carbonization columns at coal-tar processing in which phenols are regenerated from phenolate solution by carbon dioxide absorption. The design method is based on integration of local absorption rates of carbon dioxide along the column. The local absorption rates into industrial phenolate mixture are measured in a laboratory model contactor for various compositions of the gas and liquid phases under the conditions that ensure the absorption rates in the laboratory absorber simulate the local rates in the industrial column. On the bases of the calculations, two-step carbonization columns were designed for 30000 t/year of the phenolate solution treatment by carbon dioxide. The absorption proceeds at higher pressure of 500 kPa and temperatures from 50 to 65 C, pure carbon dioxide is used and toluene is added. These conditions have the ...

2009-01-15

122

Epidemiologic studies of coronary heart disease and stroke in Japanese men living in Japan, Hawaii, and California: demographic, physical, dietary, and biochemical characteristics  

International Nuclear Information System (INIS)

These summary descriptive data of ethnically similar cohorts of indigenous and migrant Japanese males have shown similarities or slight differences in characteristics wholly or largely genetically determined, such as blood groups, stature, and skeletal size. Differences have been noted in characteristics largely environmental or behavioral, such as diet and cigarette smoking habit, as well as in characteristics determined by a varying mixture of genetic and environmental influences, such as weight, blood pressure, glucose tolerance, and serum lipid and uric acid levels. Detailed analyses of the distributions of laboratory variables, of dietary data obtained by different methods, and of correlations among laboratory, dietary, physical, and demographic variables are currently in progress. Also part of the study plan are determinations of disease prevalence from evaluation of examination, laboratory, and electrocardiographic ...

123

Sealants for sources emanating Rn-222  

International Nuclear Information System (INIS)

(Oct 1974). United Kingdom Bedrosian, PH Sensintaffar, EL Gels, GL

125

Effect of Elicitation and Changes in Extracellular pH on the Cytoplasmic and Vacuolar pH of Suspension-Cultured Soybean Cells 1  

UK PubMed Central (United Kingdom)

We have employed both 31P nuclear magnetic resonance spectroscopy and two intracellular fluorescent pH indicator dyes to monitor the pH of the vacuole and cytoplasm of suspension-cultured...Full Text Available

1992-02-01

127

Alloy 800 SG tubing: current status and future challenges  

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors and in reactors in Germany. The grade of Alloy 800 tubing used for this service has a controlled Ti/C ratio ({>=}12 for CANDU SGs), and this specification is sometimes termed Alloy 800 M or Alloy 800 NG . There have been very few corrosion-related flaws detected in this material in SG service, and, until recently, no incidences of cracking. There has been extensive R and D carried out on Alloy 800 tubing, both in Canada and elsewhere, under a variety of operating conditions, including shutdowns, which show that it has excellent resistance to corrosion-related degradation under specified and appropriate operating conditions. These R and D findings are reflected in the in-service experience. It has been shown from the R and D that Alloy 800 is susceptible to corrosion under acidic conditions, in particular those that can arise as a consequence of phosphate water treatment or ...

2007-07-01

128

Alloy 800 SG tubing: current status and future challenges  

International Nuclear Information System (INIS)

Alloy 800 has been used for steam generator (SG) tubing for more than 30 years, primarily in CANDU reactors and in reactors in Germany. The grade of Alloy 800 tubing used for this service has a controlled Ti/C ratio (#>=#12 for CANDU SGs), and this specification is sometimes termed Alloy 800 M or Alloy 800 NG . There have been very few corrosion-related flaws detected in this material in SG service, and, until recently, no incidences of cracking. There has been extensive R and D carried out on Alloy 800 tubing, both in Canada and elsewhere, under a variety of operating conditions, including shutdowns, which show that it has excellent resistance to corrosion-related degradation under specified and appropriate operating conditions. These R and D findings are reflected in the in-service experience. It has been shown from the R and D that Alloy 800 is susceptible to corrosion under acidic conditions, in particular those that can arise as a consequence of phosphate water treatment or ...

2007-08-19

129

Semiconducting properties of passive films formed on stainless steels: Influence of the alloying elements  

Energy Technology Data Exchange (ETDEWEB)

Passive films formed on stainless steels in a borate buffer solution (pH 9.2) have been investigated by capacitance measurements and photoelectrochemistry. The study was carried out on films formed on AISI type 304 and 316 stainless steels and high purity alloys with differing chromium, nickel, and molybdenum contents. Complementary research by Auger analysis shows that the passive films are composed essentially of an inner chromium region in contact with the metallic substrate and an outer iron oxide region developed at the film/electrolyte interface. The semiconducting properties of the passive films are determined by those of the constituent chromium and iron oxides which are of p-type and n-type, respectively. Thus the influence of the alloying elements on the semiconducting properties of the passive films is explained by changes in the electronic structure of each of these two oxide regions.

1998-11-01

130

Passivity of iron in red mud's water solutions  

International Nuclear Information System (INIS)

Red mud suspensions are studied as passivating agents for iron in alkaline chloride media. Red mud particles in alkaline media are negatively charged, and can absorb considerable amounts of protons without significant changes in pH. These particles adhere easily to an iron surface forming aggregates of heterogeneous shape, smaller than 10 #mu#mx10 #mu#m. These adhered particles recrystallise on potential cycling, and hinder metal dissolution and magnetite formation. Carbon steel samples passivated in red mud suspensions become resistant to corrosion in alkaline chloride media. Corrosion potential versus time records and impedance spectroscopy measurements allow formulating some hypotheses about the inhibiting mechanism.

2004-07-30

131

Passivity of iron in red mud's water solutions  

Energy Technology Data Exchange (ETDEWEB)

Red mud suspensions are studied as passivating agents for iron in alkaline chloride media. Red mud particles in alkaline media are negatively charged, and can absorb considerable amounts of protons without significant changes in pH. These particles adhere easily to an iron surface forming aggregates of heterogeneous shape, smaller than 10 {mu}mx10 {mu}m. These adhered particles recrystallise on potential cycling, and hinder metal dissolution and magnetite formation. Carbon steel samples passivated in red mud suspensions become resistant to corrosion in alkaline chloride media. Corrosion potential versus time records and impedance spectroscopy measurements allow formulating some hypotheses about the inhibiting mechanism.

2004-07-30

132

Determination of selected elements by radionuclide X-ray fluorescence analysis after the separation on different kinds of sorption materials  

International Nuclear Information System (INIS)

This paper aimed to the evaluation of different kinds of sorbent material preparation and to the evaluation of their characteristics at different pH conditions by X-ray fluorescence analysis. This method is suitable for identification and determination of elements in samples of different character, state and origin because it is a polycomponent, non-destructive, fast and simple analytical method. Moreover, it allows timeadvantageous and reliable measurements. This paper studies problems concerning the determination of some selected elements (Mn, Fe, Ni, Cu, Zn, Pb) in pharmaceutical samples of sodium chloride in the solid state as well as in its solution by sorption on chelating extraction membrane 3M Empore"T"M and on the strongly acidic ion-exchanger Dowex 50Wx8. Conditions for the most effective sorption of determined elements are also interpreted. (author)

2008-03-01

133

Determination of selected elements by radionuclide X-ray fluorescence analysis after the separation on different kinds of sorption materials  

British Library Electronic Table of Contents (United Kingdom)

This paper aimed to the evaluation of different kinds of sorbent material preparation and to the evaluation of their characteristics at different pH conditions by X-ray fluorescence analysis. This method is suitable for identification and determination of elements in samples of different character, state and origin because it is a polycomponent, non-destructive, fast and simple analytical method. Moreover, it allows time-advantageous and reliable measurements. This paper studies problems concerning the determination of some selected elements (Mn, Fe, Ni, Cu, Zn, Pb) in pharmaceutical samples of sodium chloride in the solid state as well as in its solution by sorption on chelating extraction membrane 3M Empore? and on the strongly acidic ion-exchanger Dowex 50Wx8. Conditions for the most ef...

2008-01-01

134

CO2 CAPTURE BY ABSORPTION WITH POTASSIUM CARBONATE  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work is to improve the process for CO{sub 2} capture by alkanolamine absorption/stripping by developing an alternative solvent, aqueous K{sub 2}CO{sub 3} promoted by piperazine. Stripper modeling suggests the energy requirement with a simple stripper will be about the same for 5 m K{sup +}/2.5 m PZ and 7 m MEA. Modeling with a generic solvent shows that the optimum heat of CO{sub 2} desorption to minimize heat duty lies between 15 and 25 kcal/gmol. On-line pH and density measurements are effective indicators of loading and total alkalinity for the K+/PZ solvent. The baseline pilot plant campaign with 30% MEA has been started.

2005-04-29

135

University of Central Lancashire - Facilities  

Wastenet

...specialised laboratories for pharmaceutics, tissue culture and molecular biology Excellent Laboratory Facilities Tissue Culture Facilities Molecular Biology Laboratory ...

136

Use of internal quality control materials for the preparation and maintenance of reliable methods for the measurement of lead in blood  

Energy Technology Data Exchange (ETDEWEB)

The performance of a group of reference laboratories measuring lead in blood, has been monitored by an intensive external quality assessment programme, since 1974. Performance was similar to that observed in other, larger quality control surveys but rapidly improved following detailed investigations of critical factors in the analytical methodology. The introduction of a rigorous internal quality control protocol, with all laboratories using the same well-characterised materials, has produced external quality control results that are both accurate and very tightly distributed. Between-laboratory coefficients of variation of less than 5%, less than 6% and less than 20% are now obtained at concentrations of over 1.0 ..mu..mol/l (20.7 ..mu..g/dl), 0.5-1.0 ..mu..mol/l (10-20 ..mu..g/dl) and less than 0.5 ..mu..mol/l (10 ..mu..g/dl), respectively. These results represent the best that can be achieved by ...

1988-12-01

137

APMP/TCRI key comparison report of measurement of air kerma for medium-energy x-rays (APMP.RI(I)-K3)  

Energy Technology Data Exchange (ETDEWEB)

The APMP/TCRI Dosimetry Working Group performed the APMP.RI(I)-K3 key comparison of measurement of air kerma for medium-energy x-rays (100 kV to 250 kV) between 2000 and 2003. In total, 11 institutes took part in the comparison, among which 8 were APMP member laboratories. Two commercial cavity ionization chambers were used as transfer instruments and circulated among the participants. All the participants established the 100 kV, 135 kV, 180 kV and 250 kV x-ray beam qualities equivalent to those of the BIPM. The results showed that the maximum difference between the participants and the BIPM in the medium-energy x-ray range, evaluated using the comparison data of the linking laboratories ARPANSA and PTB, is less than 1.4%. The degrees of equivalence between the participants are presented and this comparison confirms the calibration capabilities of the participating laboratories. (authors)

2008-10-15

138

The influence of pH on the structure of adenine monolayers adsorbed at Au(110)/electrolyte interfaces  

Energy Technology Data Exchange (ETDEWEB)

The pH of the solution is shown to significantly effect the reflection anisotropy spectroscopy (RAS) profiles of adenine adsorbed at Au(110)/electrolyte interfaces. At pH 12.8 the net adsorption is very weak due the formation of negative adenine ions in solution. The sensitivity of the RAS profiles to the pH of the solution is probably due to a change in the geometry of the adsorbed molecules caused by a disruption of the base stacking configuration that is adopted when adenine is adsorbed from solutions at pH 7.1. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

2010-08-15

142

Hydrologic analysis for ecological risk assessment of watersheds with abandoned mine lands  

International Nuclear Information System (INIS)

As part of on-going study of acid mine drainage (AMD), a comprehensive ecological risk assessment was conducted in the Leading Creek Watershed in southeast Ohio. The watershed is influenced by agriculture and active and abandoned coal-mining operations. This work presents a broad overview of several quantitative measures of hydrology and hydraulic watershed properties available for in risk assessment and evaluates their relation to metrics of ecology. Data analysis included statistical comparisons of metrics of ecology, ecotoxicology, water quality, and physically based parameters describing land use, geomorphology, flow, velocity, and particle size. A multiple regression analysis indicated that abandoned mining operations dominated impacts upon aquatic ecology. It also indicated low flow velocity measurements and a ratio of maximum velocity to average velocity at low flow where helpful in describing variation in macroinvertebrate Total Taxa ...

1999-07-25

143

Emissions of nitrogen oxides from equatorial rain forest in central Africa: origin and regulation of NO emission from soils  

Energy Technology Data Exchange (ETDEWEB)

Emissions of nitric oxide from soils of equatorial rain forest were measured in the Dimonika Natural Park (4 degrees 30'S, 12 degrees 30'E) in the Mayombe Forest in Congo. Three research campaigns were carried out in June and July 1991 and in February 1992. Fluxes were measured by dynamic chamber techniques using a chemiluminescence instrument Scintrex LMA3. NO fluxes measured on natural soils are in between 5 and 17x10[sup 9] molecules cm[sup -2]s[sup -1]; they are of the same order of magnitude as those observed in similar tropical forest media. Soil treatment experiments show that the auto-decomposition of HNO[sub 2] in these acid soils (pH 4) (chemodenitrification) is a potentially important cause of nitric oxide production in this type of ecosystem. Nitrous acid comes from autotrophic nitrification all the year around, and also from biological denitrification, shown by N[sub 2]O ...

1994-09-01

144

Top physics at the Tevatron Collider  

Energy Technology Data Exchange (ETDEWEB)

The top quark has been discovered in 1995 at the CDF and DO experiments located in the Tevatron ring at the Fermilab laboratory. After more than a decade the Tevatron collider, with its center-of-mass energy collisions of 1.96 TeV, is still the only machine capable of producing such exceptionally heavy particle. Here I present a selection of the most recent CDF and DO measurements performed analyzing {approx} 1 fb{sup -1} of integrated luminosity.

2007-10-01

145

The proton microprobe: Applications in the biomedical field  

Energy Technology Data Exchange (ETDEWEB)

This book explores the development, present, and future applications of proton microprobes in the micrometer range. Among the topics discussed: the use of proton beams for analytical purposes; techniques of focusing or collimating ion beams; improving and measuring beam spots; the analytical capabilities of the nuclear microprobe in comparison to other micro techniques; and applications and results by several internationally known microprobe laboratories.

1986-01-01

146

Real time neutron diffraction experiments using Bragg edges  

Energy Technology Data Exchange (ETDEWEB)

Time resolved phase transition and strain experiments have been performed on the millisecond time scale using a Bragg-edge transmission technique that has been developed at the Los Alamos National Laboratory. The precision with which lattice parameters can be determined from edge positions is sufficient to perform high-resolution strain measurements in uniaxial stress.

1995-12-31

147

Real time neutron diffraction experiments using Bragg edges  

International Nuclear Information System (INIS)

Time resolved phase transition and strain experiments have been performed on the millisecond time scale using a Bragg-edge transmission technique that has been developed at the Los Alamos National Laboratory. The precision with which lattice parameters can be determined from edge positions is sufficient to perform high-resolution strain measurements in uniaxial stress.

1994-12-02

148

Performance estimates for attached-sunspace passive solar heated buildings  

Energy Technology Data Exchange (ETDEWEB)

Performance predictions have been made for attached-sunspace types of passively solar heated buildings. The predictions are based on hour-by-hour computer simulations using computer models developed in the framework of PASOLE, the Los Alamos Scientific Laboratory (LASL) passive solar energy simulation program. The models have been validated by detailed comparison with actual hourly temperature measurements taken in attached-sunspace test rooms at LASL.

1980-01-01

149

Off-line and on-line-monitoring of power transformers using the transfer function method  

Energy Technology Data Exchange (ETDEWEB)

The transfer function concept is well known as an additional method to evaluate the impulse test of power transformers in the test laboratory. Another application for the transfer function method is monitoring of transformers in service. Thereby, Off-line and On-line monitoring can be realized. Both kinds of monitoring are demonstrated with on-site measurements on a power transformer in service.

1996-12-31

150

Final Report: Planetary Instrument Definition and Design Program (PIDDP) Support Project  

Energy Technology Data Exchange (ETDEWEB)

The results of Sandia National Laboratories' participation in the NASA Planetary Definition and Design Program are summarized. Areas reported include the characterization of large area cadmium zinc telluride spectrometers and the application of simulation techniques to the prediction of device performance. Also investigated was the response of mercuric iodide devices in the region from 1 to 100 KeV. A literature study to determine the status or radiation damage measurements in room temperature semiconductor devices is also reported.

1999-03-01

151

Experimental Verification of the Hall Effect during Magnetic Reconnection in a Laboratory Plasma  

Energy Technology Data Exchange (ETDEWEB)

In this letter we report a clear and unambiguous observation of the out-of-plane quadrupole magnetic field suggested by numerical simulations in the reconnecting current sheet in the Magnetic Reconnection Experiment (MRX). Measurements show that the Hall effect is large in collisionless regime and becomes small as the collisionality increases, indicating that the Hall effect plays an important role in collisionless reconnection.

2005-06-16

152

Dispersant Effectiveness Of Heavy Fuel Oils Using The Baffled Flask Test  

Science.gov (United States)

Dispersants have been widely used as a primary response measure for marine oil spills around the world. Recently, the U.S. Environmental Protection Agency (EPA) developed an improved laboratory dispersant testing protocol, called the Baffled Flask Test (BFT). The BFT protocol w...

153

Cumulative kaon production by 10 GeV protons  

International Nuclear Information System (INIS)

The K"+- and K"-meson cumulative production cross sections are measured at 119"0 in the laboratory system on nuclei Be, Al, Cu and Ta bombarded by 10 GeV protons. Spectra of the K"-mesons consisting of only sea quarks show universal features characteristic of the spectra of cumulative particles, which contain valence quarks. Evidence is obtained for the fact that the energy density in a flucton can exceed the mean nuclear density by an order of magnitude.

154

Comparison of calculated and measured irradiated wire data for HEU and mixed HEU/LEU cores in the ORR (Oak Ridge Research Reactor)  

Energy Technology Data Exchange (ETDEWEB)

Low power wire activations are being performed in the Oak Ridge Research Reactor (ORR) as part of the whole-core LEU demonstration experiments. Calculations of the demonstration cores, including simulation of the wire activations, are being performed at Argonne National Laboratory (ANL). This paper presents the results of comparisons for 293 wires from five cores and shows that, on the average, the integrated activities agree within 6%.

1986-01-01

155

Comment on 'Magnetic braking revisited: activities for the undergraduate laboratory'  

International Nuclear Information System (INIS)

Here, we consider a recent paper concerned with magnetic braking by induced currents (Ireson and Twidle 2008 Eur. J. Phys. 29 745-51). Our objective is to elucidate why measurement of speed in which a magnet is dropped through a non-ferromagnetic conductive tube depends on its geometry in a non-monotonic way, which was not clearly explained by the authors. (letters and comments)

2009-03-01

156

Automated remote positioning and examination of FFTF reactor power characterization dosimeters  

Energy Technology Data Exchange (ETDEWEB)

The Fast Flux Test Facility (FFTF) reactor characterization by the Hanford Engineering Development Laboratory (HEDL) includes extensive neutronic measurements during startup and initial operation. To aid in the handling and counting of the thousands of passive dosimeters used as part of this effort, an automated dosimetry specimen handling, positioning, and counting system was designed and developed by Westinghouse Hanford for the Department of Energy.

1981-05-04

157

Analytical peak fitting for gamma-ray spectrum analysis with Ge detectors  

Energy Technology Data Exchange (ETDEWEB)

A comparison of maximum likelihood (or chi-square) and Bayesian peak fitting techniques shows that the latter can reduce peak intensity uncertainties by a factor of up to ten in the case of closely separated doublets, leading to greatly improved doublet resolution. The need for laboratories to demonstrate the reliability of their chosen peak fitting techniques and measures of peak intensity is also demonstrated. (orig.)

1993-10-01

158

Analytical peak fitting for gamma-ray spectrum analysis with Ge detectors  

International Nuclear Information System (INIS)

A comparison of maximum likelihood (or chi-square) and Bayesian peak fitting techniques shows that the latter can reduce peak intensity uncertainties by a factor of up to ten in the case of closely separated doublets, leading to greatly improved doublet resolution. The need for laboratories to demonstrate the reliability of their chosen peak fitting techniques and measures of peak intensity is also demonstrated. (orig.).

159

An instrument for measuring spatial and time characteristics of sea agitation in coastal zones  

Energy Technology Data Exchange (ETDEWEB)

Resistive analogous meters for spatial and time characteristics in ocean agitation are most often used in practical oceanography in coastal zones but are based on bridge circuits determined to have shortcomings in their linearity range. This shortcoming is eliminated in the circuit of an instrument developed in an oceanographic laboratory (IMIO, Vana). Principle and block circuits are indicated, and static calibration curves are presented as are the correlative functions in the frequency spectrums obtained with the help of sea agitation recorded at a fixed point and at a depth of 6 meters.

1981-01-01

160

Crosscheck of different techniques for two dimensional power spectral density measurements of x-ray optics  

Energy Technology Data Exchange (ETDEWEB)

The consistency of different instruments and methods for measuring two-dimensional (2D) power spectral density (PSD) distributions are investigated. The instruments are an interferometric microscope, an atomic force microscope (AFM) and the X-ray Reflectivity and Scattering experimental facility, all available at Lawrence Berkeley National Laboratory. The measurements were performed with a gold-coated mirror with a highly polished stainless steel substrate. It was shown that these three techniques provide essentially consistent results. For the stainless steel mirror, an envelope over all measured PSD distributions can be described with an inverse power-law PSD function. It is also shown that the measurements can be corrected for the specific spatial frequency dependent systematic errors of the instruments. The AFM and the X-ray scattering measurements were used ...

2005-07-12

161

Cross-check of different techniques for two-dimensional powerspectral density measurements of X-ray optics  

Energy Technology Data Exchange (ETDEWEB)

The consistency of different instruments and methods for measuring two-dimensional (2D) power spectral density (PSD) distributions are investigated. The instruments are an interferometric microscope, an atomic force microscope (AFM) and the X-ray Reflectivity and Scattering experimental facility, all available at Lawrence Berkeley National Laboratory. The measurements were performed with a gold-coated mirror with a highly polished stainless steel substrate. It was shown that these three techniques provide essentially consistent results. For the stainless steel mirror, an envelope over all measured PSD distributions can be described with an inverse power-law PSD function. It is also shown that the measurements can be corrected for the specific spatial frequency dependent systematic errors of the instruments. The AFM and the X-ray scattering measurements were used ...

2005-04-17

162

Proposed subcritical measurements for fresh and spent highly enriched plate type fuel assemblies  

Energy Technology Data Exchange (ETDEWEB)

A collaborative experimental research program has been established between industry and university partners to evaluate the subcritical behavior of fresh and spent highly enriched fuel assemblies at the University of Missouri Research Reactor (MURR). This proposed program will involve a series of subcritical measurements using the Oak Ridge National Laboratory (ORNL) developed {sup 252}Cf source-driven noise technique. Measurements evaluating the subcritical behavior of simple arrays of fresh MURR assemblies will be performed for evaluating the spectral effects of materials typically found in shipping casks such as lead, steel, aluminum, and boron. Also, measurements will be performed on spent assemblies to characterize physics parameters which may be useful in determining the subcritical behavior of fuels for reactivity credit of actinide burnup and fission product poisoning.

1997-09-01

163

High-precision Absolute Distance and Vibration Measurement using Frequency Scanned Interferometry  

CERN Document Server

In this paper, we report high-precision absolute distance and vibration measurements performed simultaneously with frequency scanned interferometry using a pair of single mode optical fibers. Absolute distance was determined by counting the interference fringes produced while scanning the laser frequency. A high-finesse Fabry-Perot interferometer(F-P) was used to determine frequency changes during scanning. Two multi-distance-measurement analysis techniques were developed to improve distance precision and to extract the amplitude and frequency of vibrations. Under laboratory conditions, a precision of 40 nm was demonstrated for an absolute distance of approximately 0.45 meters using the first analysis technique. The second analysis technique has capability to measure vibration frequencies ranging from 0.1 Hz to 100 Hz with minimal amplitude on few nanometers order without a priori knowledge.

2004-01-01

164

Development of in-vessel reflood instrumentation at ORNL  

International Nuclear Information System (INIS)

A program under the sponsorship of the United States Nuclear Regulatory Commission was intiated at the Oak Ridge National Laboratory (ORNL) in late 1977. The program, Advanced Instrumentation for Reflood Studies (AIRS), is charged with developing instrumentation for measurement of in-vessel fluid phenomena in pressurized water reactor reflood facilities. The goal of the ORNL program is to develop techniques and systems for measuring fluid flow in-core, deentrainment in the upper plenum and liquid fallback from the upper plenum into the core. A large portion of the development at ORNL is devoted to the impedance probes for measurement of two-phase flow velocities and void fractions. Film probe development at ORNL is limited to adapting the present techniques to the environment of a reflood facility. As the development progresses on all the measurement techniques, ORNL will fabricate ...

2004-09-06

165

Corrective measures evaluation work plan Technical Area V groundwater.  

Energy Technology Data Exchange (ETDEWEB)

This document, which is prepared as directed by the Compliance Order on Consent (COOC) issued by the New Mexico Environment Department, identifies and outlines a process to evaluate remedial alternatives to identify a corrective measure for the Sandia National Laboratories New Mexico Technical Area (TA)-V Groundwater. The COOC provides guidance for implementation of a Corrective Measures Evaluation (CME) for the TA-V Groundwater. This Work Plan documents an initial screening of remedial technologies and presents a list of possible remedial alternatives for those technologies that passed the screening. This Work Plan outlines the methods for evaluating these remedial alternatives and describes possible site-specific evaluation activities necessary to estimate remedy effectiveness and cost. These methods will be reported in the CME Report. This Work Plan outlines the CME Report, including key components and a description of ...

2004-04-01

166

Corrective measures evaluation work plan : Technical Area V Groundwater : revision 0.  

Energy Technology Data Exchange (ETDEWEB)

This document, which is prepared as directed by the Compliance Order on Consent (COOC) issued by the New Mexico Environment Department, identifies and outlines a process to evaluate remedial alternatives to identify a corrective measure for the Sandia National Laboratories/New Mexico Technical Area (TA)-V Groundwater. The COOC provides guidance for implementation of a Corrective Measures Evaluation (CME) for the TA-V Groundwater. This Work Plan documents an initial screening of remedial technologies and presents a list of possible remedial alternatives for those technologies that passed the screening. This Work Plan outlines the methods for evaluating these remedial alternatives and describes possible site-specific evaluation activities necessary to estimate remedy effectiveness and cost. These methods will be reported in the CME Report. This Work Plan outlines the CME Report, including key components and a description of ...

2004-12-01

167

A high sensitivity two-color interferometer for pulsed power plasmas  

International Nuclear Information System (INIS)

A high sensitivity, high bandwidth, two-color interferometer (1064 and 532 nm) has been tested on the Hawk pulsed power generator at the Naval Research Laboratory. The phase resolution is 10"-"5 waves with a rise time of 3 ns, a new capability for diagnosing plasmas, and neutrals in pulsed power experiments. The two-color feature is used to distinguish phase shifts from free (plasma) electrons and bound (neutral and ion) electrons. Simultaneous electron and neutral density measurements were demonstrated in a plasma opening switch (POS) experiment. The ability to measure small phase shifts with fast rise time were demonstrated in a plasma filled diode experiment. The high sensitivity and vibration isolation enable neutral gas distribution measurements from supersonic nozzles used in plasma radiation source experiments. Examples of these measurements and future applications are ...

168

Warm waters, bleached corals  

Science.gov (United States)

Two researchers, Tom Goreau of the Discovery Laboratory in Jamaica and Raymond Hayes of Howard University, claim that they have evidence that nearly clinches the temperature connection to the bleached corals in the Caribbean and that the coral bleaching is an indication of Greenhouse warming. The incidents of scattered bleaching of corals, which have been reported for decades, are increasing in both intensity and frequency. The researchers based their theory on increased temperature of the seas measured by satellites. However, some other scientists feel that the satellites measure the temperature of only the top few millimeters of the water and that since corals lie on reefs perhaps 60 to 100 feet below the ocean surface, the elevated temperatures are not significant.

1990-10-12

169

The Daya Bay reactor neutrino experiment  

International Nuclear Information System (INIS)

Search for the value of ?13 mixing angle is of importance in understanding the lepton flavor mixing matrix, and in motivating future experiments to probe CP violation in the lepton sector. Among the present experimental approaches, reactor experiment can provide a clean laboratory for the ?13-measurement. The Daya Bay experiment will start civil construction this year at Daya Bay, Guangdong, China. The goal of this experiment is to reach a sensitivity in sin2 2?13 of < 0.01 at 90% C.L. by precisely measuring the disappearance and spectral distortion of reactor electron anti-neutrinos with multiple identical detectors at different baselines. The talk will present the current status and prospects of the experiment.

2008-07-01

170

Residual stress measurements on a stress relieved Zircaloy-4 weld by neutron diffraction  

Energy Technology Data Exchange (ETDEWEB)

The macroscopic stress distribution across an annealed Zircaloy-4 gas tungsten arc weld was measured by neutron time-of-flight diffraction at the SMARTS diffractometer at Los Alamos National Laboratory. The stresses after annealing are about 40% lower than those in the same weld prior to heat treatment. The intergranular strains in the reference coupons, which give the macroscopic stress free lattice spacings, are consistent with the difference in cooling the strongly textured plate and the weakly textured weld.

2006-12-15

171

INEEL BNCT research program. Annual report, January 1, 1996--December 31, 1996  

Energy Technology Data Exchange (ETDEWEB)

This report is a summary of the progress and research produced for the Idaho National Engineering and Environmental Laboratory (INEEL) Boron Neutron Capture Therapy (BNCT) Research Program for calendar year 1996. Contributions from the individual investigators about their projects are included, specifically, physics: treatment planning software, real-time neutron beam measurement dosimetry, measurement of the Finnish research reactor epithermal neutron spectrum, BNCT accelerator technology; and chemistry: analysis of biological samples and preparation of {sup 10}B enriched decaborane.

1997-04-01

172

Gamma Radiation Detectors of the TA-55 Waste Line Monitoring System  

Energy Technology Data Exchange (ETDEWEB)

This report covers the gamma detectors, measurement instrumentation, and testing results of a system developed at Los Alamos National Laboratory. This system monitors the process liquid waste streams at the Plutonium Facility (TA-55) for the presence of radioactive contamination. The detectors are at various points on the acid, caustic, and industrial waste lines. Two of the detectors are on the sanitary sewer lines from the facility. A custom interface unit associated with these two detectors furnishes the facility operation center with a notification of the detection of material. All of the detectors furnish measurement information to a central computer system for storage and trending.

1999-06-01

173

Fission neutron multiplicity for the /sup 242m/Am(n,f) reaction  

International Nuclear Information System (INIS)

This paper analyzes fission neutron multiplicity for the /sup 242m/Am(n,f) reaction. The fission neutron multiplicity, v bar, of /sup 242m/Am(n,f) was measured relative to that of /sup 235/U(n,f) using the neutron time-of-flight facility at the Lawrence Livermore National Laboratory 100-MeV electron Linac. A comparison of the measured energy dependence of v-bar is made with semi-empirical models of neutron emission from the actinides. 22 refs.

174

Examination of the natural radioactivity of building materials  

International Nuclear Information System (INIS)

Most important radionuclides naturally appearing in minerals used to form building materials are described. The frequently met ranges of concentrations of these radionuclides in the building materials composed from natural products as well as from power-plant wastes and metallurgic plant wastes are discussed and propositions concerning the limitation of presence of radioactive nuclides in the building materials are given, with special concern paid to materials for dwelling and public utility buildings. The elaborated technique of measuring potassium 40, radium 226 and thorium 228 concentrations is presented. Data on the organization of controlling-and-measuring laboratories in this field are given. (author).

1982-01-01

175

Directional wind-measurement derived from elastic backscatter lidar data in real-time  

Energy Technology Data Exchange (ETDEWEB)

The development of a capability to infer wind velocities simultaneously at a number of ranges along one direction in real time is described. The elastic backscatter lidar data used was obtained using the XM94 lidar, developed by Los Alamos National Laboratory for the US Army Chemical and Biological Detection Command. In some respects this problem is simpler than measuring wind velocities on meso-meteorological scales. Other requirements, particularly high temporal fidelity, have driven the development of faster software algorithms and suggested opportunities for the evolution of the hardware.

1996-04-01

176

Comprehensive view of BMFT-funded research on forest decline. Gesamtdarstellung der oeffentlich gefoerderten Forschung ueber Waldschaeden  

Energy Technology Data Exchange (ETDEWEB)

Since 1983, about 600 research projects received a total of DM 250 million public funds for the following tasks: - Development of scientific fundamentals for monitoring and observation of forest decline and its ecological and economic consequences. - Investigation of the cause-effect relationship of forest damage, with particular regard to the involvement of the various compartments of the forest ecosystem and to the contribution of different pollutants. - Development of the scientific fundamentals required for forestry measures to accompany the air pollution abatement measures. The investigations comprised both laboratory and field tests. The findings and conclusion are summarized. (orig./MG).

1988-12-01

177

Effect of external pH on the cytoplasmic and vacuolar pHs in Mung bean root-tip cells. A T P nuclear magnetic resonance study  

Energy Technology Data Exchange (ETDEWEB)

The effect of the external pH on the intracellular pH in mung bean (Vigna mungo (L.) Hepper) root-tip cells was investigated with the T P nuclear magnetic resonance (NMR) method. The T P NMR spectra showed three peaks caused by cytoplasmic G-6-P, cytoplasmic Psub(i) and vacuolar Psub(i). The cytoplasmic and vacuolar pHs could be determined by comparing the Psub(i) chemical shifts with the titration curve. When the external pH was changed over a range from pH 3 to 10, the cytoplasmic pH showed smaller changes than the vacuolar pH, suggesting that the former is regulated more strictly than the latter. The H -ATPase inhibitor, DCCD, caused the breakdown of the mechanism that regulates the intracellular pH. H -ATPase appears to have an important part in the regulation of the intracellular pH.

1984-12-01

178

Effect of external pH on the cytoplasmic and vacuolar pHs in Mung bean root-tip cells  

International Nuclear Information System (INIS)

The effect of the external pH on the intracellular pH in mung bean (Vigna mungo (L.) Hepper) root-tip cells was investigated with the "3"1P nuclear magnetic resonance (NMR) method. The "3"1P NMR spectra showed three peaks caused by cytoplasmic G-6-P, cytoplasmic Psub(i) and vacuolar Psub(i). The cytoplasmic and vacuolar pHs could be determined by comparing the Psub(i) chemical shifts with the titration curve. When the external pH was changed over a range from pH 3 to 10, the cytoplasmic pH showed smaller changes than the vacuolar pH, suggesting that the former is regulated more strictly than the latter. The H"+-ATPase inhibitor, DCCD, caused the breakdown of the mechanism that regulates the intracellular pH. H"+-ATPase appears to have an important part in the regulation of the intracellular pH. (author).

179

Reference materials to evaluate measurement systems for the nutrient composition of foods: results from USDA?s National Food and Nutrient Analysis Program (NFNAP)  

British Library Electronic Table of Contents (United Kingdom)

Over a 6.5-year period a total of 2554 values were reported by nine laboratories for 259 certified or reference nutrient concentrations in 26 certified reference materials (CRM) submitted to contract laboratories, blinded, as part of the qualifying process for analytical contracts and in the routine sample stream as part of the National Food and Nutrient Analysis Program. Each value was converted to a Z?-score, reflecting the difference from the assigned value related to the combined expected analytical uncertainty plus the uncertainty in the CRM value. Z?-scores >|3.0| were considered unacceptable. For some nutrients (Na, folate, dietary fiber, pantothenic acid, thiamin, tocopherols, carotenoids, monounsaturated, and polyunsaturated fatty acids), >20% of Z?-scores were >|3.0|. For total f...

2007-01-01

180

Neutron star evolution and emission  

Science.gov (United States)

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The authors investigated the evolution and radiation characteristics of individual neutron stars and stellar systems. The work concentrated on phenomena where new techniques and observations are dramatically enlarging the understanding of stellar phenomena. Part of this project was a study of x-ray and gamma-ray emission from neutron stars and other compact objects. This effort included calculating the thermal x-ray emission from young neutron stars, deriving the radio and gamma-ray emission from active pulsars and modeling intense gamma-ray bursts in distant galaxies. They also measured periodic optical and infrared fluctuations from rotating neutron stars and search for high-energy TeV gamma rays from discrete celestial sources.

1997-08-01

181

Interfacial Charge Transport in Organic Electronic Materials: the Key to a New Electronics Technology  

Energy Technology Data Exchange (ETDEWEB)

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The primary aim of this project is to obtain a basic scientific understanding of electrical transport processes at interfaces that contain an organic electronic material. Because of their processing advantages and the tunability of their electronic properties, organic electronic materials are revolutionizing major technological areas such as information display. We completed an investigation of the fundamental electronic excitation energies in the prototype conjugated polymer MEH-PPV. We completed a combined theoretical/experimental study of the energy relation between charged excitations in a conjugated polymer and the metal at a polymer/metal interface. We developed a theoretical model that explains injection currents at polymer/metal interfaces. We have made electrical ...

1999-06-04

182

Insitu Assessment of Contaminant Containment Systems  

Environmental Research Database

Objectives(1) Evaluate various insitu techniques for determination of the permeability of slurry walls and investigate the extent of material disturbance and fracturing during drilling and testing.~%~~%~(2) Perform laboratory tests of block samples obtained from the field testing site and compare the results with field measurements.~%~~%~(3) Investigate the mechanisms of drilling using a newly developed instrumented self-boring device and develop a theoretical framework for drilling mechanisms in soils.~% [continued...]DescriptionCement-bentonite and clay liner systems are used as components of containment systems by the environmental industry to control the migration of pollution. In the interest of public safety, following construction, there is a requirement to test these structures in orde to assess if they meet the design critetia. At present this is done only indirectly via ...

2006-01-30

183

Impact of the addition of chicken litter on mercury speciation and emissions from coal combustion in a laboratory-scale fluidized bed combustor  

Energy Technology Data Exchange (ETDEWEB)

Co-combustion of chicken litter with coal was performed in a laboratory-scale fluidized bed combustor to investigate the effect of chicken litter addition on the partitioning behavior of mercury. Gaseous total and elemental mercury concentrations in the flue gas were measured online, and ash was analyzed for particle-bound mercury along with other elemental and surface properties. The mercury mass balance was between 85 and 105%. The experimental results show that co-combustion of chicken litter decreases the amount of elemental and total mercury in the gas phase. Mercury content in fly ash increases with an increasing chicken litter share. 22 refs., 6 figs., 5 tabs.

2008-07-15

184

Explosive performance on the non-proliferation experiment  

Energy Technology Data Exchange (ETDEWEB)

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

1994-03-01

185

EBIT - Electronic Beam Ion Trap: N Divison experimental physics annual report 1995  

Energy Technology Data Exchange (ETDEWEB)

The multi-faceted research effort of the EBIT (Electron Beam Ion Trap) program in N-Division of the Physics and Space Technology Department at Lawrence Livermore National Laboratory (LLNL) continues to contribute significant results to the physical sciences from studies with low energy very highly charged heavy ions. The EBIT program attracts a number of collaborators from the US and abroad for the different projects. The collaborations are partly carried out through participating graduate students demonstrating the excellent educational capabilities at the LLNL EBIT facilities. Moreover, participants from Historically Black Colleges and Universities are engaged in the EBIT project. This report describes EBIT work for 1995 in atomic structure measurements and radiative transition probabilities, spectral diagnostics for laboratory and astrophysical plasmas, ion/surface interaction studies, electron-ion interactions studies, ...

1996-10-01

186

Development and validation of control materials for the measurement of vitamin D3 in selected US foods  

British Library Electronic Table of Contents (United Kingdom)

As part of the United States Department of Agricultures (USDA) National Food and Nutrient Analysis Program (NFNAP), food composition data for vitamin D in the USDA National Nutrient Database for Standard Reference are being updated and expanded, focusing on high priority foods and validated analytical methodology. A lack of certified reference materials and analytical methods validated for these key foods required the development of five matrix-specific control composite materials (CC) (canned salmon and vitamin D3 fortified cereal, orange juice, milk, and cheese). Each of six experienced laboratories (research and commercial) analyzed vitamin D3 in five subsamples of each CC in five separate analytical batches, with one subsample of each material in each run. Research laboratories perform...

2008-01-01

187

Systems Analysis of Safeguards Effectiveness in a Uranium Conversion Facility  

Energy Technology Data Exchange (ETDEWEB)

The U.S. Department of Energy (DOE) is interested in developing tools and methods for potential U.S. use in designing and evaluating safeguards systems. For this goal several DOE National Laboratories are defining the characteristics of typical facilities of several size scales, and the safeguards measures and instrumentation that could be applied. Lawrence Livermore National Laboratory is providing systems modeling and analysis of facility and safeguards operations, diversion path generation, and safeguards system effectiveness. The constituent elements of diversion scenarios are structured using directed graphs (digraphs) and fault trees. Safeguards indicator probabilities are based on sampling statistics and/or measurement accuracies. Scenarios are ranked based on value and quantity of material removed and the estimated probability of non-detection. Significant scenarios, especially those involving ...

2004-06-16

188

Radioxenons: Their role in monitoring a Comprehensive Test Ban Treaty  

Energy Technology Data Exchange (ETDEWEB)

Monitoring for xenon radionuclides which are produced in a nuclear detonation can provide a strong deterrent to the violation of a Comprehensive nuclear Test Ban Treaty (CTBT). There are 18 known radioactive xenon isotopes produced in nuclear fission with half-lives ranging from less than one second to 11.9 days. However, only four of these remain in significant amounts more than a day after a detonation. In order for radioxenon monitoring to be practical, it was necessary to develop an automated measurement system which could operate unattended for periods of months, measure the entire spectrum of radioxenons, and provide hundreds of times better sensitivities than current laboratory procedures. This capability was developed at the US Department of Energy`s Pacific Northwest National Laboratory based on rapid separation of atmospheric xenon coupled with a unique high sensitivity ...

1996-06-01

189

Performance of the upgraded LTP-II at the ALS Optical Metrology Laboratory  

Energy Technology Data Exchange (ETDEWEB)

The next generation of synchrotrons and free electron laser facilities requires x-ray optical systems with extremely high performance, generally of diffraction limited quality. Fabrication and use of such optics requires adequate, highly accurate metrology and dedicated instrumentation. Previously, we suggested ways to improve the performance of the Long Trace Profiler (LTP), a slope measuring instrument widely used to characterize x-ray optics at long spatial wavelengths. The main way is use of a CCD detector and corresponding technique for calibration of photo-response non-uniformity [J. L. Kirschman, et al., Proceedings of SPIE 6704, 67040J (2007)]. The present work focuses on the performance and characteristics of the upgraded LTP-II at the ALS Optical Metrology Laboratory. This includes a review of the overall aspects of the design, control system, the movement and measurement regimes for the stage, and analysis of the ...

2008-07-14

190

Isochron measurements of naturally irradiated K-feldspar grains  

International Nuclear Information System (INIS)

The equivalent doses of K-feldspar grains in a range of grain sizes from 90 to 250#mu#m diameter were measured using a single-aliquot regenerative-dose protocol for the infrared stimulated luminescence (IRSL) signals for two samples of desert sand. The equivalent doses for each sample were compared with that for the 125-150#mu#m grains of quartz from the same samples. The results suggested that the K-feldspar equivalent doses were underestimated because of anomalous fading. Measurements of the decay of the IRSL signals following laboratory irradiation for these two samples, and an additional one from a previously published isochron study, showed anomalous fading during the period of laboratory storage. The decay rate was about 3% per decade for all samples and was independent of the grain size used. Using plots of equivalent doses for K-feldspars as a function of their calculated internal dose rate, and ...

2007-09-01

191

Phosphate/UO{sub 2} interaction during in vitro dissolution of inhalable particles in a medium simulating the phagolysosomal compartment  

Energy Technology Data Exchange (ETDEWEB)

Qualitative and quantitative methods have been developed to relate phosphate/UO{sub 2} interactions and U dissolution, in vitro, in a medium containing 0 or 10 mM phosphate concentrations at pH 5. This was performed by Energy Dispersive X ray Spectrometry (EDS) at 200 kV on entire particles and by fluorimetric measurement. The U dissolution rate was larger in a medium without phosphate than in a medium containing 10 mM phosphate. During the first day, the initial U dissolution involved 80.55% and 91.13% of the powder in media with and without phosphate respectively. From 5 to 15 d after beginning the assay, the dissolution half-times were longer than 92 d and 22 d for media with and without phosphate. EDS analyses have shown a constant P/U X ray intensity ratio for reference U{sub 2}O(PO{sub 4}){sub 2} for the same range of particle diameter. A gradual increase of this ratio was measured for UO{sub 2} incubated in a 10 mM ...

1998-07-01

192

Passivation behavior of SUS 304 stainless steel in neutral solutions at elevated temperature  

International Nuclear Information System (INIS)

Cyclic voltammograms of SUS 304 stainless steel in various neutral solutions such as Na_2SO_4 at high temperature were measured, as a successive study to previous report in which effects of temperature and pH on polarization behavior of stainless steel were studied. In this measurement Ag/AgCl reference electrode and platinum counter electrode were used in a static autoclave lined with inconel. Passive films formed in various conditions were analysed by electron diffraction and Auger spectroscopy. Results obtained were compared with anodic behavior of iron, chromium and nickel and with thermodynamical stabilities of their compounds. The main results are summarized as follows. (1) Stainless steel shows such electrochemical behavior as active dissolution, passivation and transpassivation in a deaerated neutral solution at 250"0C after fully reductive treatment of the specimen. In air-saturated solution, the peak of active ...

1981-01-01

193

Kinetic studies of preactivated derivatives of cyclophosphamide by "3"1P NMR spectroscopy  

International Nuclear Information System (INIS)

Selected derivatives of cyclophosphamide (CP) metabolites were synthesized and the solution chemistry of each was studied by "3"1P nuclear magnetic resonance (NMR) spectroscopy under a standard set of reaction conditions at physiological pH (7.4) and temperature (37"0C). Complementary "2H and "1"3C NMR spectral data was obtained using isotopically ("2G and "1"3C) enriched CP metabolites. The CP derivatives were synthesized by the ozonolysis of substituted 3-butenyl phosphorodiamidates, and were isolated as analogues of either cis and trans 4-hydroperoxy-CP or aldophosphamide (AP). The relative ratios of the tautomeric species, 4-hydroxy-CP and AP, and their half-lives (T/sub 1/2/) were measured by "3"1P NMR spectroscopy. The influence of CP metabolites on perfused U-937 cells, a CP-sensitive human lymphoma, was observed by high resolution "3"1P NMR spectroscopy. In this manner, it was possible to measure, for the first ...

194

Impedance analysis of hydrogen adsorption on palladium in 0. 1 M NaOH solution  

Energy Technology Data Exchange (ETDEWEB)

The behaviour of hydrogen adsorption on palladium has been investigated by a.c. impedance measurements in 0.1 M NaOH solution of pH 13 at 298 K. The electrode impedance has been measured by superimposing an a.c. voltage of 5 mV amplitude ranging between 10{sup -1} and 10{sup 4} Hz on a d.c. potential range from -0.76 to 0.44 V (standard hydrogen electrode (SHE)). The equivalent circuit representing the hydrogen adsorption reaction is proposed from the analysis of the frequency dependence of electrode admittance. The capacitance, arising from the adsorbed hydrogen, has been determined as a function of applied potential by complex non-linear least-squares curve fitting method based on the proposed equivalent circuit. As the cathodic applied potential increased from -0.36 to -0.76 V (SHE), the adsorption capacitance considerably increased owing to the enhanced coverage of hydrogen adsorbed on the palladium surface. In the ...

1991-10-21

195

2008 Data Report: Groundwater Monitoring Program Area 5 Radioactive Waste Management Site  

Science.gov (United States)

This report is a compilation of the groundwater sampling results from the Area 5 Radioactive Waste Management Site (RWMS) including calendar year 2008 results. Each of the three Pilot Wells was sampled on March 11, 2008, and September 10, 2008. These wells were sampled for the following indicators of contamination: pH, specific conductance, total organic carbon, total organic halides, and tritium. Indicators of general water chemistry (cations and anions) were also monitored. Results from all samples collected in 2008 were within the limits established by agreement with the Nevada Division of Environmental Protection for each analyte. These data indicate that there has been no measurable impact to the uppermost aquifer from the Area 5 RWMS. There were no significant changes in measured groundwater parameters compared to previous years. Other information in the report includes an updated Cumulative Chronology for the Area ...

2009-01-13

196

2006 Data Report: Groundwater Monitoring Program Area 5 Radioactive Waste Management Site  

Science.gov (United States)

This report is a compilation of the groundwater sampling results from the Area 5 Radioactive Waste Management Site (RWMS) for calendar year 2006. Pilot wells UE5PW-1, UE5PW-2, and UE5PW-3 were sampled in April and October 2006 for the following indicators of contamination: pH, specific conductance, total organic carbon, total organic halides, and tritium. Indicators of general water chemistry (cations and anions) were also monitored. Results from all samples collected in 2006 were within the limits established by agreement with the Nevada Division of Environmental Protection for each analyte. These data indicate that there has been no measurable impact to the uppermost aquifer from the Area 5 RWMS. There were no significant changes in measured groundwater parameters compared to previous years. Other information in the report includes an updated Cumulative Chronology for the Area 5 RWMS Groundwater Monitoring Program and a ...

2007-02-01

197

Plasma testosterone levels are related to various aspects of locomotor activity in wild-caught male meadow voles (Microtus pennsylvanicus).  

Science.gov (United States)

The relationship between plasma testosterone levels and locomotor activity in wild-caught sexually mature male meadow voles (Microtus pennsylvanicus) was assessed in the laboratory. Several aspects of locomotor activity were monitored for 1 h on two consecutive days using the automated Digiscan activity monitoring system. Plasma testosterone levels were determined immediately following the second day of activity monitoring. Significant Pearson correlations were obtained between plasma testosterone levels and total distance traveled [r(10) = 0.55, p < 0.05] and amount of time spent in movement [r(10) - 0.55, p < 0.05] on the second day. The wild voles showed a reduction in activity levels from the first to the second day of activity monitoring, which is indicative of habituation to a novel environment. This study provides direct evidence for a significant correlation between laboratory measures of behavioral activity ...

1998-04-01

198

Advances on experimental techniques for the characterization of THM behaviour of bentonite  

Energy Technology Data Exchange (ETDEWEB)

The design of high level radioactive waste (HLW) repositories in deep geological media in which bentonite clay is proposed as a sealing material leads to the need of further studying the behaviour of highly compacted expansive soils when subjected to mechanical, hydraulic and thermal changes. Laboratory tests may help to understand the processes that take place in the clay barrier under simple and controlled conditions and to develop the governing equations. The laboratory tests enable to isolate the different processes, making their interpretation easier, and provide with fundamental data concerning the parameters to be used in the models. The extremely low permeability of these materials, their avidity for water (high suction) and their high swelling capacity make necessary the modification of the conventional laboratory techniques and procedures to determine basic physical parameters. The main hydraulic properties of the ...

2005-07-01

199

Turn-key Raman lidar for profiling atmospheric water vapor, clouds, and aerosols at the US Southern Great Plains Climate Study Site  

Energy Technology Data Exchange (ETDEWEB)

There are clearly identified scientific requirements for continuous profiling of atmospheric water vapor at the Department of Energy, Atmospheric Radiation Measurement program, Southern Great Plains CART (Cloud and Radiation Testbed) site in northern Oklahoma. Research conducted at several laboratories has demonstrated the suitability of Raman lidar for providing measurements that are an excellent match to those requirements. We have developed and installed a ruggedized Raman lidar system that resides permanently at the CART site, and that is computer automated to eliminate the requirements for operator interaction. In addition to the design goal of profiling water vapor through most of the troposphere during nighttime and through the boundary layer during daytime, the lidar provides quantitative characterizations of aerosols and clouds, including depolarization measurements for particle phase studies.

1997-12-31

200

Thermal electron attachment and detachment, and electron affinities  

International Nuclear Information System (INIS)

Knighton et al. used a pulsed high pressure mass spectrometer to examine thermal electron detachment from C_6F_6"-. This technique had been used earlier for the measurement or detachment rate coefficients for azulene anions as a function of temperature. C_6F_6"- and c-C_4F_6"- have been studied by Datskos et al. using a pulsed drift tube. In our laboratory, we have used a flowing afterglow Langmuir probe (FALP) apparatus to measure the thermal electron detachment rate coefficient for c-C_4F_8"- ions at 375 K. We have also measured the electron attachment rate coefficient for c-C_4F_8 at 303 K and 375 K. (author).

1994-03-20

201

Neutrino cross sections with the MINER?A Experiment  

British Library Electronic Table of Contents (United Kingdom)

MINER?A is a high resolution, fully active detector designed to study neutrino interactions on nuclei in the NuMI beam at Fermi National Accelerator Laboratory. The active volume of the detector consists of 3 tons of plastic scintillator and includes embedded targets of 4He, C, H2O, Fe and Pb. The MINER?A collaboration expects to perform precision, A-dependent neutrino cross section measurements in the 1?10 GeV region, measure the axial form factor, and study nuclear shadowing of F2, quark-hadron duality and coherent pion production, among other topics. MINER?A began data taking in the fall of 2009. This paper describes the MINER?A experiment and provides an overview of the physics objectives along with estimated uncertainties of the measurements and the tentative projected schedule of dat...

2011-01-01

202

Indoor and outdoor Radon concentration measurements in Sivas, Turkey, in comparison with geological setting  

British Library Electronic Table of Contents (United Kingdom)

Indoor and soil gas Radon (222Rn) concentration measurements were accomplished in two stages in Sivas, a central eastern city in Turkey. In the first stage, CR-39 passive nuclear track detectors supplied by the Turkish Atomic Energy Authority (TAEA) were placed in the selected houses throughout Sivas centrum in two seasons; summer and winter. Before the setup of detectors, a detailed questionnaire form was distributed to the inhabitants of selected houses to investigate construction parameters and properties of the houses, and living conditions of inhabitants. Detectors were collected back two months later and analysed at TAEA laboratories to obtain indoor 222Rn gas concentration values. In the second stage, soil gas 222Rn measurements were performed using an alphameter near the selected h...

2010-01-01

203

Characteristics of infrared-stimulated luminescence from a feldspar at low temperatures  

International Nuclear Information System (INIS)

The characteristics of infrared-stimulated luminescence (IRSL) from a sample of potassium feldspar at low temperatures are presented. These studies extend the previous work from this laboratory on the optical bleaching characteristics and emission spectra of feldspars at room temperature and recent measurements of the stimulated spectrum for a sample of potassium feldspar at room temperature. Stimulation spectra have been measured at 290, 160 and 145 K. By fitting Gaussian functions to the spectra, the peak position is shown to shift to higher photon energies at lower temperatures and the full-width half-maximum of the peak to reduce with decreasing temperature. The variation of IRSL intensity with temperature for several stimulating wavelengths has been determined and the form of the IRSL decay curve measured at 290 and 160 K. No substantial differences were observed in the form of the decay curves at ...

1993-07-01

204

Use of a predictor for total body potassium content: application to nutrition and hypertension  

International Nuclear Information System (INIS)

Total body potassium (TBK), measured at different institutions, has no reference standard for comparison. A useful reference formula, however, based on body size and age, has been derived at the Brookhaven National Laboratory. This formula was used to help calibrate a simple whole body counter for measuring total potassium and applied to nutrition and hypertension studies. A sodium iodide detector was used for counting gamma rays emitted by potassium-40 to estimate TBK. The mean ratio (+/- S.D.) of adjusted TBK measurements to predicted values was 1.002 +/- 0.047. The ratio of lean body mass estimated by the TBK measurement to that derived from skin fold thickness was 1.069 +/- 0.056. In hypertensives on low dose thiazide, the ratio of TBK measurements to predicted values was 0.994 +/- 0.052. Thus, our TBK measurements were adjusted in close ...

205

The models of experimental magnetic measurements of various biological samples  

International Nuclear Information System (INIS)

Complete text of publication follows. At the Geomagnetic Institute, in the Laboratory for paleomagnetism and archeomagnetism research and at the Geomagnetic Observatory, Grocka (GCK) during the period from November 2004 to February 2008 the researchers carried out experimental magnetic measurements of the total-intensity gradient of the magnetic field vector (changes in the total magnetisation vector) of various biomaterials. Measurements of the gradient total intensity of the magnetic field vector were carried out by GSM-19 magnetometers of high accuracy and recording resolution (accuracy: #DELTA#F=0.1 nT; sampling rate: 1-5 per second). During these experimental biomagnetic measurements samples of water, tissue, blood, cotton, wool, pitch and magnetite-powder were used. In this study, the part of the biomagnetic measurement results relate to the water, blood and tissue. The ...

2009-08-23

206

Effect of borehole size, mudcake, and standoff on the photoelectric absorption index measurement  

Energy Technology Data Exchange (ETDEWEB)

The photoelectric absorption index, I/sub Pe/, is accepted as an accurate measurement for the description of formation lithology. The measured I/sub Pe/ has been shown to deviate slightly for a given lithology because of the effects of porosity. Properly calibrated and measured I/sub Pe/'s, however, have been observed to deviate from predicted values in practice, even considering the influence of porosity. Such departures were traced to variations in borehole size and tool standoff. The nature of the physical method of recording an I/sub Pe/ does not ensure independence from the influence of the borehole environment. A series of laboratory experiments has been conducted in test formations to verify and to characterize the influence of borehole size, mudcake, and standoff on I/sub Pe/ measurement. A set of nomographs has been constructed that allows correction of I/sub Pe/ ...

1989-06-01

207

Intestinal alkaline phosphatase regulates protective surface microclimate pH in rat duodenum  

UK PubMed Central (United Kingdom)

Regulation of localized extracellular pH (pHo) maintains normal organ function. An alkaline microclimate overlying the duodenal enterocyte brush border protects the mucosa from luminal acid....Full Text Available

2009-07-15

208

Effect of pH and Temperature on Denitrification Gene Expression and Activity in Pseudomonas mandelii?  

UK PubMed Central (United Kingdom)

Pseudomonas mandelii liquid cultures were studied to determine the effect of pH and temperature on denitrification gene expression, which was quantified by quantitative reverse transcription-PCR....Full Text Available

2009-06-01

209

Cytoplasmic pH Regulation in Acer pseudoplatanus Cells  

UK PubMed Central (United Kingdom)

Qualitative and quantitative aspects of the mechanisms involved in the regulation of cytoplasmic pH during an acid-load have been studied in Acer pseudoplatanus cells. Two main processes,...Full Text Available

1986-11-01

210

Comparison of Disulfide Contents and Solubility at Alkaline pH of Insecticidal and Noninsecticidal Bacillus thuringiensis Protein Crystals  

UK PubMed Central (United Kingdom)

We compared two insecticidal and eight noninsecticidal soil isolates of Bacillus thuringiensis with regard to the solubility of their proteinaceous crystals at alkaline pH values. The...Full Text Available

1994-10-01

211

Bimodal MR-PET agent for quantitative pH imaging  

UK PubMed Central (United Kingdom)

Activatable or “smart” magnetic resonance contrast agents have relaxivities that depend on environmental factors such as pH or enzymatic activity, but the MR signal depends on...Full Text Available

2010-03-22

212

Uranium isotopic assay instrument  

International Nuclear Information System (INIS)

Full text: The isotopic assay instrument under development at Pacific Northwest National Laboratory (PNNL) is capable of rapid prescreening to detect small and rare particles containing high concentrations of uranium in a heterogeneous sample. The isotopic measurement concept is based on laser vaporization of solid samples followed by sensitive isotope-specific detection using either uranium atomic fluorescence emission or uranium atomic absorbance. Both isotopes are measured concurrently, following a single ablation laser pulse using two external-cavity violet diode lasers. The simultaneous measurement of both isotopes enables the correlation of the fluorescence and absorbance signals on a shot-to-shot basis. This measurement approach demonstrated negligible channel crosstalk between isotopes. Scanning the heterogeneous samples provides high-resolution imagery of sample isotopic ...

2006-10-16

213

Intercomparison of Retrospective Radon Detectors  

Energy Technology Data Exchange (ETDEWEB)

We performed both a laboratory and field intercomparison of two novel glass-based retrospective radon detectors previously used in major radon case-control studies performed in Missouri and Iowa. The new detectors estimate retrospective residential radon exposure from the accumulation of a long-lived radon decay product, Pb-210, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha emission of a Pb-210 decay product, Po-210. The detector's track density generation rate (tracks cm{sup -2} hr{sup -1}) is proportional to the surface alpha activity. In the absence of other strong sources of alpha emission in the glass, the implanted surface alpha activity should be proportional to the accumulated Po-210 and hence, the cumulative radon gas exposure. The goals of the intercomparison were to: (1) perform collocated measurements using two different glass-based ...

1998-11-01

215

The virtual fast-ion loss detector  

International Nuclear Information System (INIS)

English 2009 p. 79 Ukraine Brudgam, M. Lauber, Ph. Garcia Munoz, M.

2009-09-21

217

Fundamental Investigations in Operations Research  

Science.gov (United States)

... in the Vicinity of Terminal Areas," Ph. ... WORDS Operations Research Stochastic processes Mathematical ... theory Aut',matic control Queueing theory ...

1970-09-30

218

Extraction of magnesium as the iodide by tributyl phosphate  

Science.gov (United States)

The extraction of magnesium by tributyl phosphate from KI solutions was investigated. With increasing KI and TBP concentrations, the extraction increased. The maximum extraction (82%) was attained at pH 4, and it did not decrease with a further pH increase. With decreasing pH, the extraction decreased because of HI extraction. The magnesium was extracted as the compound MgI/sub 2/ x 4TBP. Complexone III (at pH 3-4) does not affect the extraction of magnesium, which makes it possible to use it to mask other metals.

1987-08-20

219

Incident angle modifiers for flat-plate solar collectors: analysis of measurement and calculation procedures  

Energy Technology Data Exchange (ETDEWEB)

Existing test procedures for measuring and rating thermal performance require the determination of the angular response of collectors in order to account for nonnormal incident beam irradiance. Angular response measurements for four different types of collectors, each type tested by three different laboratories, are presented and analyzed. Substantial differences, both within and between laboratories, are reported for the same type collectors. An analysis of the measurement procedure shows that experimentally determined angular response parameters are subject to relatively large uncertainties. The problem results to a large extent from measuring collector efficiencies at non-normal incident angles where measurement uncertainty is of the same order of magnitude as the efficiency reduction attributable to these off-normal angles. Other factors ...

1982-11-01

220

Iodine-123-labeled pH shift brain-imaging agents  

International Nuclear Information System (INIS)

HIPDM is an "1"2"3I-labeled agent with a distribution in brain reflecting regional perfusion. This compound is neutral and lipid soluble at blood pH and freely crosses the blood-brain barrier. At the lower pH in brain, it picks up a hydrogen ion and becomes positively charged. In this form the molecule is not lipid soluble and it is trapped in brain.

1982-05-03

221

Humic substances in natural waters and their complexation with trace metals and radionuclides: a review. [129 references  

Energy Technology Data Exchange (ETDEWEB)

Dissolved humic substances (humic and fulvic acids) occur in surface waters and groundwaters in concentrations ranging from less than 1 mg(C)/L to more than 100 mg(C)/L. Humic substances are strong complexing agents for many trace metals in the environment and are also capable of forming stable soluble complexes or chelates with radionuclides. Concentrations of humic materials as low as 1 mg(C)/L can produce a detectable increase in the mobility of some actinide elements by forming soluble complexes that inhibit sorption of the radionuclides onto rock materials. The stability of trace metal- or radionuclide-organic complexes is commonly measured by an empirically determined conditional stability constant (K'), which is based on the ratio of complexed metal (radionuclide) in solution to the product concentration of uncomplexed metal and humic complexant. Larger values of stability constants indicate greater complex stability. The stability of ...

1985-07-01

222

Enhanced biosorption of nickel(II) ions by silica-gel-immobilized waste biomass: Biosorption characteristics in batch and dynamic flow mode  

Energy Technology Data Exchange (ETDEWEB)

Batch and dynamic flow biosorption studies were carried out using the waste biomass entrapped in silica-gel matrix for the removal of nickel(II) ions from synthetic solutions and real wastewater. Batch biosorption conditions were examined with respect to initial pH, S/L ratio, contact time, and initial nickel ion concentration. Zeta potential measurements showed that immobilized biosorbent was negatively charged in the pH range of 3.0-8.0. The immobilized biomass was found to possess relatively high biosorption capacity (98.01 mg g{sup -1}), and biosorption equilibrium was established in a short time of operation (5 min). The equilibrium data were followed by Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models. Scanning electron microscope analysis was used to screen the changes on the surface structure of the waste biomass after immobilization and nickel(II) biosorption. Sorbent-sorbate interactions were ...

2009-04-30

223

Electrodeposition and electrochemical characterisation of thick and thin coatings of Sb and Sb/Sb{sub 2}O{sub 3} particles for Li-ion battery anodes  

Energy Technology Data Exchange (ETDEWEB)

The possibilities to electrodeposit thick coatings composed of nanoparticles of Sb and Sb{sub 2}O{sub 3} for use as high-capacity anode materials in Li-ion batteries have been investigated. It is demonstrated that the stability of the coatings depends on their Sb{sub 2}O{sub 3} concentrations as well as microstructure. The electrodeposition reactions in electrolytes with different pH and buffer capacities were studied using chronopotentiometry and electrochemical quartz crystal microbalance measurements. The obtained deposits, which were characterised with XRD and SEM, were also tested as anode materials in Li-ion batteries. The influence of the pH and buffer capacity of the deposition solution on the composition and particle size of the deposits were studied and it is concluded that depositions from a poorly buffered solution of antimony-tartrate give rise to good anode materials due to the inclusion of precipitated Sb{sub ...

2007-12-20

224

Preliminary study of the application of natural olivine in Cenozoic dating  

Energy Technology Data Exchange (ETDEWEB)

The study investigated the luminescence behaviour of natural olivine to discuss the potential for Cenozoic (quaternary) dating. The UV-blue thermoluminescence (TL) glow curves of irradiated olivines have a resolved peak at 190 deg. C and other peaks at higher temperature at lower dose levels, and broad signals around 275-310 and 375-400 deg. C at higher dose levels. The UV-blue TL increases with additional laboratory dose to {approx}1.6kGy within a plateau temperature region, suggesting the possibility of dosimetry and Cenozoic dating. Both infrared stimulated luminescence (IRSL) and blue light stimulated luminescence (BLSL) were detected from laboratory-irradiated olivines although the BLSL was weaker than the IRSL. Furthermore, post-BL IRSL was detected but post-IR BLSL was not observed. Therefore, IR stimulation is recommended for optically stimulated luminescence measurements with natural olivine. The growth of the IRSL ...

2006-08-15

225

Radionuclide Distribution Coefficients for Sediments Collected from Borehole 299-E17-21: Final Report for Subtask 1a  

Energy Technology Data Exchange (ETDEWEB)

Over 360 distribution coefficients (KJ for cesium, iodine, selenium, Strontium, technetium, and uranium were measured in fiscal year 1998 using 20 sediments collected fkom borehole 299-El 7-21 on the Hanford Site as part of the Immobilized Low-Activity Waste-Performance Assessment (ILAW-PA). Additionally, the pH and cation-exchange capacity (a measure of the total quantity of cations that a sediment can adsorb) of these sediment samples were measured. The sediment samples originated from the Hanford formation (informal name). Statistical analyses, using Student's t-test and correlation were conducted with the measured values. There were no significant differences between layers 1 and 2 for the selenium, strontium, technetium, and uranium & values (statistics could not be applied to evaluate layer 3 &values). Significant differences between the cesium and ...

1998-10-14

226

NPDGamma: A Measurement of the Parity-Violating Gamma Asymmetry A in n-p Capture  

Energy Technology Data Exchange (ETDEWEB)

The NPDGamma Experiment measures the parity-violating correlation A{sub {Gamma}Y} between neutron spin and photon momentum in the reaction {rvec n} + p {yields} d + {gamma}. Knowledge of A{sub {Gamma}Y} and other parity-violating observables in few-body nuclear systems will provide constraints for a parameterized description of {Delta}S = 0 parity-violating phenomena free from complications of nuclear structure. The NPDGamma experiment uses a polarized cold pulsed neutron beam, a liquid parahydrogen target, and a cylindrical array of 48 CsI(Tl) scintillation detectors operated in current mode to search for the asymmetry. NPDGamma recently completed the first phase of the program to measure A{sub {Gamma}Y} at the Los Alamos Neutron Science Center with the preliminary result A{sub {Gamma}Y} = (-1.2 {+-} 2.1(stat.) {+-} 0.1(sys.)) x 10{sup -7}, reproducing the previous upper limit from a measurement at a reactor facility. We ...

2010-01-01

227

[Fast neutron cross section measurements]. Progress report  

Energy Technology Data Exchange (ETDEWEB)

In this report, we outline the progress achieved in two distinct under the DOE-sponsored cross section project: the initial results obtained from the pulsed 14 MeV neutron facility, and a cooperative effort with Argonne National Laboratory in the measurement of fast neutron cross sections in yttrium. In the 14 MeV neutron laboratory, this year has seen the maturation of the project into one in which initial scattering measurements are now underway. We have improved the accelerator and ion source in several significant ways, so that neutron intensities have now been proven to be adequate for our series of elastic scattering angular distribution measurements outlined in our initial proposal of two years ago. We have successfully tested all components of the time-of-flight spectrometer and recorded initial neutron spectra from the ring targets that we have obtained for our first ...

1991-12-31

228

Bench-scale Kinetics Study of Mercury Reactions in FGD Liquors  

Energy Technology Data Exchange (ETDEWEB)

This document is the final report for Cooperative Agreement DE-FC26-04NT42314, 'Kinetics Study of Mercury Reactions in FGD Liquors'. The project was co-funded by the U.S. DOE National Energy Technology Laboratory and EPRI. The objective of the project has been to determine the mechanisms and kinetics of the aqueous reactions of mercury absorbed by wet flue gas desulfurization (FGD) systems, and develop a kinetics model to predict mercury reactions in wet FGD systems. The model may be used to determine optimum wet FGD design and operating conditions to maximize mercury capture in wet FGD systems. Initially, a series of bench-top, liquid-phase reactor tests were conducted and mercury species concentrations were measured by UV/visible light spectroscopy to determine reactant and byproduct concentrations over time. Other measurement methods, such as atomic absorption, were used to measure ...

2008-03-31

229

Refractometry of organosilica microspheres  

CERN Document Server

The refractive index of novel organosilica (nano/micro)material is determined using two methods. The first method is based on analysis of optical extinction efficiency of organosilica beads versus wavelength, which is obtained by a standard laboratory spectrometer. The second method relies on the measurable trapping potential of these beads in the focused light beam (laser tweezers). Polystyrene beads were used to test these methods, and the determined dispersion curves of refractive index values have been found accurate. The refractive index of organosilica beads has been determined to range from 1.60-1.51 over the wavelength range of 300-1100 nm.

2007-01-01

230

Radon in soil-air and in groundwater related to major geophysical events: A survey  

Energy Technology Data Exchange (ETDEWEB)

The various technical aspects of radon concentration measurements in the ground or in the groundwater are reviewed. The emphasis is put on the most convenient techniques particularly suited for in situ monitoring in the field. Some attention is paid to the thoron problem. Historical and most recent findings in the field or earthquake related radon anomalies are presented and briefly discussed. A similar approach is made to rarer volcanic cases that have been documented up to now. A short discussion regarding the various models that intend to provide satisfactory explanations is presented, supported, whenever it is possible, by experimental laboratory results. Finally a glimpse on the possible and future application of the method to hydrogeology is given. (orig.).

1992-04-15

231

Midwest Superconductivity Consortium: 1994 Progress report  

Energy Technology Data Exchange (ETDEWEB)

The mission of the Midwest Superconductivity Consortium, MISCON, is to advance the science and understanding of high {Tc} superconductivity. During the past year, 27 projects produced over 123 talks and 139 publications. Group activities and interactions involved 2 MISCON group meetings (held in August and January); with the second MISCON Workshop held in August; 13 external speakers; 79 collaborations (with universities, industry, Federal laboratories, and foreign research centers); and 48 exchanges of samples and/or measurements. Research achievements this past year focused on understanding the effects of processing phenomena on structure-property interrelationships and the fundamental nature of transport properties in high-temperature superconductors.

1995-01-01

232

Kinetics of salt concentration in heated crevices  

International Nuclear Information System (INIS)

In PWR steam-generators, the crevice between tube and tube-support plate tends to fill with porous deposits during operation and acts as a concentration site for chemicals in the boiler water, which may lead to corrosion of the tube and tube-support-plate. The rate of concentration, the magnitude of the concentration factor and the rate of release of solute when conditions change are important parameters for devising strategies to minimize corrosion. Values of these parameters for salt concentration have therefore been measured in a laboratory simulation of the crevice and are used to formulate a model of the concentrating process.

1985-03-01

233

Hydrogen flame acceleration and transition to detonation  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the results obtained from two large experimental facilities built at Sandia National Laboratories in Albuquerque, NM. FLAME (Flame Acceleration Measurements and Experiments) is a large horizontal rectangular channel designed to study flame acceleration, transition to detonation, simulation of combustion in containment geometries, component heating, and other problems in hydrogen combustion relevant to reactor safety. The Heated Detonation Tube has been designed to study detonations in hydrogen-air-steam mixtures. Both facilities have been in operation for just over a year. 12 figures.

1984-01-01

234

Hydrogen flame acceleration and transition to detonation  

International Nuclear Information System (INIS)

This paper describes the results obtained from two large experimental facilities built at Sandia National Laboratories in Albuquerque, NM. FLAME (Flame Acceleration Measurements and Experiments) is a large horizontal rectangular channel designed to study flame acceleration, transition to detonation, simulation of combustion in containment geometries, component heating, and other problems in hydrogen combustion relevant to reactor safety. The Heated Detonation Tube has been designed to study detonations in hydrogen-air-steam mixtures. Both facilities have been in operation for just over a year. 12 figures.

1984-10-23

235

Evaluation of Townsend's first ionization and attachment coefficients from prebreakdown current measurements  

International Nuclear Information System (INIS)

Hitherto in this laboratory, ionization coefficients alpha and attachment coefficients #eta# have been determined from Townsend's discharge experiments by a curve-fitting method. However, the method proved to be laborious, Formulae have been derived in this paper to give value of alpha and #eta# as a function of Isubo, Isub1 and Isub2 where Isubo is the photoelectric current at a gap setting d and Isub2 the current at another gap setting 2 d. The values of alpha and #eta# obtained give currents in agreement to within 3% in the best cases with the observed currents.

236

Development of high resolution imaging detectors for X-ray astronomy  

Energy Technology Data Exchange (ETDEWEB)

High (spatial) resolution imaging detectors for X-ray astronomy were developed. Several prototype detectors built and their feasibility and baseline performance were assessed. Two of these detector types are proposed for investigations on the advanced X-ray astrophysics facility (AXAF). The readiness of a new X-ray imaging system, the charge coupled device (CCD) imaging specctrometer is outlined, and state of the art performance parameters for microchannel plate (MCP) and CCD detectors are measured. Laboratory facilities and procedures for coating MCP are developed general high resolution imagery systems are analyzed.

1985-03-01

237

Development of high resolution imaging detectors for X-ray astronomy  

International Nuclear Information System (INIS)

High (spatial) resolution imaging detectors for X-ray astronomy were developed. Several prototype detectors built and their feasibility and baseline performance were assessed. Two of these detector types are proposed for investigations on the advanced X-ray astrophysics facility (AXAF). The readiness of a new X-ray imaging system, the charge coupled device (CCD) imaging specctrometer is outlined, and state of the art performance parameters for microchannel plate (MCP) and CCD detectors are measured. Laboratory facilities and procedures for coating MCP are developed general high resolution imagery systems are analyzed.

1985-01-01

238

Determining surface profile from sequential interference patterns from a long trace profiler  

Energy Technology Data Exchange (ETDEWEB)

The Long Trace Profiler (Takacs et al.) is a slope-measuring instrument which was introduced several years ago. Development of this instrument continues at Lawrence Berkeley Laboratory in improving both hardware design and software algorithms for turning the raw interference data (a sequence of intensity patterns) into properly interpreted representations of surface slope and height. This report presents a mathematical model of the interference pattern and methods of extracting the slope and height profile from such patterns. 9 refs.

1991-07-01

239

Constraints on extra dimensions from cosmological and terrestrial measurements  

CERN Document Server

If quantum fields exist in extra compact dimensions, they will give rise to a quantum vacuum or Casimir energy. That vacuum energy will manifest itself as a cosmological constant. The fact that supernova and cosmic microwave background data indicate that the cosmological constant is of the same order as the critical mass density to close the universe supplies a lower bound on the size of the extra dimensions. Recent laboratory constraints on deviations from Newton's law place an upper limit. The allowed region is so small as to suggest that either extra compact dimensions do not exist, or their number is about to be tightly constrained by experimental data.

2001-01-01

240

Constraints on Extra Dimensions from Cosmological and Terrestrial Measurements  

CERN Document Server

If quantum fields exist in extra compact dimensions, they will give rise to a quantum vacuum or Casimir energy. That vacuum energy will manifest itself as a cosmological constant. The fact that supernova and cosmic microwave background data indicate that the cosmological constant is of the same order as the critical mass density to close the universe supplies a lower bound on the size of the extra dimensions. Recent laboratory constraints on deviations from Newton's law place an upper limit. The allowed region is so small as to suggest that either extra compact dimensions do not exist, or their properties are about to be tightly constrained by experimental data.

2000-01-01

241

Calculations of the self-amplified spontaneous emission performance of a free-electron laser.  

Energy Technology Data Exchange (ETDEWEB)

The linear integral equation based computer code (RON: Roger Oleg Nikolai), which was recently developed at Argonne National Laboratory, was used to calculate the self-amplified spontaneous emission (SASE) performance of the free-electron laser (FEL) being built at Argonne. Signal growth calculations under different conditions are used for estimating tolerances of actual design parameters. The radiation characteristics are discussed, and calculations using an ideal undulator magnetic field and a real measured magnetic field will be compared and discussed.

1999-04-20

242

Application of the GEM shutdown device to the FFTF reactor  

Energy Technology Data Exchange (ETDEWEB)

A novel device called the gas expansion model (GEM) is being developed at the Hanford Engineering Development Laboratory for testing in the 400-MW(th) fast flux test facility (FFTF) reactor. Incorporation of the GEM into liquid-metal reactor designs is intended to measurably contribute to the achievement of inherent safety, by allowing the reactor to passively shut down even in the extremely remote (hypothetical) event of an unprotected (no scram) loss-of-flow accident. The purpose of this paper is to describe the GEM and present predictive analyses of the effectiveness of the device during unprotected loss-of-flow experiments in the FFTF.

1986-01-01

243

Application of the GEM shutdown device to the FFTF reactor  

International Nuclear Information System (INIS)

A novel device called the gas expansion model (GEM) is being developed at the Hanford Engineering Development Laboratory for testing in the 400-MW(th) fast flux test facility (FFTF) reactor. Incorporation of the GEM into liquid-metal reactor designs is intended to measurably contribute to the achievement of inherent safety, by allowing the reactor to passively shut down even in the extremely remote (hypothetical) event of an unprotected (no scram) loss-of-flow accident. The purpose of this paper is to describe the GEM and present predictive analyses of the effectiveness of the device during unprotected loss-of-flow experiments in the FFTF.

1986-11-16

244

Algorithm for assessment of mean annual gonad dose and genetically significant dose from the data of personal dosimetry  

International Nuclear Information System (INIS)

During one year more than 40,000 items of information on radiation exposure of personnel involved in the handling of radiation sources and more than 5,000,000 items on irradiation of other people are collected in the authors' laboratory. Considerable progress in assessment of mean annual gonad dose of genetically sifnificant dose was attained by means of an algorithm for a personal computer. This simple and inexpensive system has led to a higher accuracy in the application of protective measures. (author).

1985-10-22

245

A study on diagnostic techniques of pump operating condition  

Energy Technology Data Exchange (ETDEWEB)

The scope and contents investigate and reviewed are as follows : establishment of study plan and references survey, review of related problems and inservice test standards of safety injection pump in use nuclear power plant, review of the study results in laboratory, the theoretical investigation of temperature rise according to mini-flow rate of pump, mini-flow rate working characteristics of high and low pressure injection pumps at nuclear power plants, setup of testing equipment for measuring ampere, discharge pressure and vibration, selection and behaviors analysis of major parameters concerning pump degradation.

1998-03-15

246

A study of aging effects in gas proportional detectors at the BAC calorimeter of the ZEUS experiment  

Energy Technology Data Exchange (ETDEWEB)

The multicell proportional chambers at the backing calorimeter of the ZEUS experiment at the storage ring HERA are supplied with a gas mixture of Ar/CO[sub 2] by an open gas system. Flow proportional counters with the build-up [sup 55]Fe sources are used as gas system monitoring detectors. The ZEUS experiment is planned to collect data for about 10 years. Therefore, the lifetime of the Ar/CO[sub 2] mixture should be known. In this paper, the results of laboratory tests and preliminary measurements of the aging effects for monitoring counters are presented. ((orig.))

1994-09-01

247

WASTE SOLIDIFICATION BUILDING BENCH SCALE HIGH ACTIVITY WASTE SIMULANT VARIABILITY STUDY FY2008  

Energy Technology Data Exchange (ETDEWEB)

The primary objective of this task was to perform a variability study of the high activity waste (HAW) acidic feed to determine the impact of feed variability on the quality of the final grout and on the mixability of the salt solution into the dry powders. The HAW acidic feeds were processed through the neutralization/pH process, targeting a final pH of 12. These fluids were then blended with the dry materials to make the final waste forms. A secondary objective was to determine if elemental substitution for cost prohibitive or toxic elements in the simulant affects the mixing response, thus providing a more economical simulant for use in full scale tests. Though not an objective, the HAW simulant used in the full scale tests was also tested and compared to the results from this task. A statistically designed test matrix was developed based on the maximum molarity inputs used to make the acidic solutions. The maximum molarity inputs were: 7.39 HNO{sub 3}, 0.11618 ...

2009-03-20

248

pH and iodide ion effect on corrosion inhibition of histidine self-assembled monolayer on copper  

International Nuclear Information System (INIS)

Self-assembled monolayer (SAM) of histidine (His) was prepared on copper surface at various pH values. The effect of KI additives on corrosion protection efficiency of His SAM was also studied. The protection abilities of these films against copper corrosion in 0.5 M HCl aqueous solution were investigated using electrochemical impedance spectroscopy and polarization techniques. The results show that the film formed on the electrode is more stable at pH = 10 than that at other pH values. When the iodide ions were added into the His self-assembly solution (pH = 10), protection efficiency was further improved. The inhibition mechanism has been discussed by quantum chemical calculations.

2010-03-01

249

Synthesis and Crystal Structures of Octahedral Metal Complexes containing the New Dianion [PhP(Se,O)Se-Se(O,Se)PPh]2-  

British Library Electronic Table of Contents (United Kingdom)

The synthesis and structures of three new compounds are reported. [Mg2{PhP(Se,O)Se-Se(O,Se)PPh}2(thf)7(H2O)3] (1), [Mg{PhP(Se,O)Se-Se(O,Se)PPh}(thf)3(H2O)] (2), and [Mn{PhP(Se,O)Se-Se(O,Se)PPh}(thf)3(H2O)] (3) were prepared by treatment of Woollins reagent [PhP(Se)(m-Se)]2 with the corresponding hydrated metal acetates.

2007-01-01

250

Investigation of passive films on nickel Alloy 690 in lead-containing environments  

Energy Technology Data Exchange (ETDEWEB)

Passive films formed on Alloy UNS N06690 were investigated in simulated crevice chemistries. It was found the role of lead in corrosion processes is strongly dependent on the pH value of the testing solutions. At pH 1.5 the effect of lead is narrowly noticeable; while at pH 12.7, lead has a significant influence on the electrochemical performance of alloy UNS N06690. The lead alters the surface morphologies at both pH and account for higher hydroxide content in the surface film at pH 12.7. The lead incorporation hinders the formation of spinel oxides during the passivation in alkaline solution. Nanoindentation tests indicate a significant lead-induced degradation in the mechanical properties of passive films. The passivation degradation is attributed to detrimental effects of lead via interrupting the dehydration process and hindering the formation of protective layers on the alloy ...

2008-09-01

251

Mathematical modeling of x-probe eddy current array coils used in tube inspection  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a mathematical model that calculates eddy current signals from laterally spaced transmit-receive pancake coils. This model was validated by comparing calculations with laboratory measurements and it has been applied to evaluating design variations in X-Probe eddy current array coils. This model was used to quantify detection capabilities of probe designs with different numbers of coils. The current standard X-Probe design for 13 mm (0.5 inch) diameter steam generator tubes uses 3 rows of coils with 8 coils per row. This design is commonly referred to as the '8 coil X-Probe'. A significant improvement in detection capability was predicted for an X-Probe with 12 coils per row (called the '12 coil X-Probe') detecting short circumferential crack-like flaws. Based on these calculations, a prototype 12 coil X-Probe was constructed and used in laboratory ...

2004-11-15

252

Aggregation of silica nanoparticles directed by adsorption of lysozyme.  

Science.gov (United States)

The interaction of the globular protein lysozyme with silica nanoparticles of diameter 20 nm was studied in a pH range between the isoelectric points (IEPs) of silica and the protein (pH 3-11). The adsorption affinity and capacity of lysozyme on the silica particles is increasing progressively with pH, and the adsorbed protein induces bridging aggregation of the silica particles. Structural properties of the aggregates were studied as a function of pH at a fixed protein-to-silica concentration ratio which corresponds to a surface concentration of protein well below a complete monolayer in the complete-binding regime at pH > 6. Sedimentation studies indicate the presence of compact aggregates at pH 4-6 and a loose flocculated network at pH 7-9, followed by a sharp decrease of aggregate size near the IEP of lysozyme. The structure of the ...

2011-07-20

253

Study of Pd-Sn/Al{sub 2}O{sub 3} catalysts prepared by an oxide colloidal route; Etude de catalyseurs Pd-Sn/Al{sub 2}O{sub 3} prepares par voie colloidale oxyde  

Energy Technology Data Exchange (ETDEWEB)

The oxide colloidal route, developed in the laboratory for mono-metallic catalysts, consists in preparing a metallic oxide hydro-sol which leads to the supported catalyst after deposition onto a support and an activation stage. In this work, this method has been adapted to the preparation of alumina supported bimetallic Pd-Sn catalysts to determine its interest for the control of the properties of the bimetallic phase (size, composition and structure). In the preliminary study concerning tin oxide sols, SnO{sub 2} (size=2,3 nm) and Sn{sub 6}O{sub 4}(OH){sub 4} (size = 25 nm) nano-particles were synthesized by neutralization respectively for tin(IV) and tin(H). The control through the pH of the aggregation of the PdO and SnO{sub 2} particles revealed that increasing oxide solubility promotes integral re-dispersion of the oxide particles. To synthesize oxide bimetallic sols, three strategies were defined. Copolymerization (formation of a mixed ...

2001-09-01

254

Evaluation of a process for the decontamination of radioactive hotspots due to activated stellite particles  

International Nuclear Information System (INIS)

Some of the Indian pressurized heavy water reactors (PHWRs) which use Stellite balls in the ball and screw mechanism of the adjustor rod drive mechanism in the moderator circuit have encountered high radiation fields in the moderator system due to "6"0Co. Release of particulate Stellite is responsible for the hotspots in addition to the general uniform contamination of internal surfaces with "6"0Co. Extensive laboratory studies have shown that it is possible to dissolve these Stellite particles by adopting a three-step redox process with permanganic acid as the oxidizing agent. These investigations with inactive Stellite in powder form helped to optimize the process conditions. Permanganic acid was found to have the highest dissolution efficiency as compared to alkaline and nitric acid permanganate. The susceptibility of Stellite to corrode or dissolve was found to depend on the concentration of the permanganate, pH and temperature of the ...

2011-06-01

255

Effect of energy intake on the metabolism of glucose and glutamine in rumen epithelial tissue  

International Nuclear Information System (INIS)

Ten Holstein steers (579 kg average body weight) were fed either alfalfa hay (12.2% crude protein) or a 90% concentrate diet to supply 14.2 or 25.2 Mcal ME respectively for a minimum of 28 days. Samples of rumen epithelial tissue were removed at slaughter from the anterior ventral sac, washed free of feed particles and transported to the laboratory in oxygenated Krebs-Ringer bicarbonate buffer (KRB; pH 7.4). Papillae were weighed (100-200 mg) in triplicate into flasks containing 3 ml KRB with 1 mM glutamine or 5 mM glucose and acetate (50 mM), propionate (25 mM), butyrate (15 mM), lactate (1 mM) and glucose (5 mM) or glutamine (1 mM) as competing substrates. A parallel set of flasks contained 1 or .5 #mu#Ci of [U-"1"4C]-glutamine or glucose respectively for "1"4CO_2 production. There were no interactions with dietary energy intake and substrate addition. Increasing the dietary energy intake increased (P < .01) rates of uptake, "1"4CO_2 ...

1986-04-13

256

Combined distiller waste utilisation and combustion gases desulphurisation method. The case study of soda-ash industry  

Energy Technology Data Exchange (ETDEWEB)

In this paper, a concept of technology that can be helpful for lowering the negative influence of the synthetic (based on the Solvay process) soda ash plant on the natural environment is presented. We describe the desulphurisation of combustion gases from the factory's power plant, which is based on their absorption in the overflow of distiller waste. The excess of lime milk, which is added in the process of ammonia regeneration from filter liquor, results in a strong alkalinity of distiller waste. The high pH of distiller waste favours absorption of acidic combustion gases. The laboratory-scale tests showed about 80% efficiency of the desulphurisation process. The suspension samples we obtained consist mainly of CaCO{sub 3}. We suggest using the obtained solid phase as an adsorbent-insert in Fluidised Bed Combustion technology (FBC). Based on raw material prices, production costs, and average sell prices of the product, economic ...

2007-09-15

257

Characterization of aluminum surfaces: Sorption and etching  

Science.gov (United States)

Aluminum, due to its low density and low cost, is a key material for future lightweight applications. However, like other structural materials, aluminum is subject to various forms of corrosion damage that annually costs the United States approximately 5% of its GNP [1]. The main goal is to investigate the effects of various solution anions on aluminum surfaces, and specifically probe pit initiation and inhibition. Using surface analysis techniques including X-ray photoelectron spectroscopy, Auger electron spectroscopy, and scanning electron microscopy, results have been correlated with those obtained from electrochemical methods and a radiolabeling technique developed in the Wieckowski laboratory. Analysis of data has indicated that important variables include type of anion, solution pH, and applied electrode potential. While aggressive anions such as chloride are usually studied to elucidate corrosion processes to work ultimately toward ...

2001-01-01

258

Urinary tract infection: diabetic women's strategies for prevention.  

Science.gov (United States)

Urinary tract infection (UTI) is a common problem in the female population. Women with diabetes mellitus are possibly at a higher risk. The usual medical therapy for UTI is antibiotic treatment. The aim of this study is to explore strategies employed by diabetic women for prevention and self-treatment of UTI. Forty-two women with diabetes mellitus who had experienced at least one episode of UTI in the last six months were included. Data collection included background information, questions about prevention and self-treatment strategies and a clinical examination to measure maximal urine flow, residual urine, a blood test evaluating diabetic control (HbA1c) and a urine test strip for determination of glucose, leucocytes, nitrite, blood, protein and pH. Thirty-five participants (83.3%) reported changes in daily routines like 'always keeping warm', 'increased fluid intake', 'good personal hygiene' as prevention strategies. Different herb and plant ...

259

The influence of copper and chromium on the semiconducting behaviour of passive films formed on weathering steels  

Energy Technology Data Exchange (ETDEWEB)

The influence of small amounts of alloying elements (0.36% Cu and 0.47% Cr) on the semiconducting properties of passive films formed on weathering steels was investigated either in tetraborate/boric acid buffer solution (pH 9.2) or artificial atmospheric environment (SO{sub 2}-containing environment). The electrochemical behaviour was assessed by potentiodynamic polarisation, capacitance measurements and photoelectrochemistry. The chemical characterisation of the films was carried by Auger electron spectroscopy. The polarization results obtained in the buffer solution show that the addition of chromium decreases the passive current density. The capacitance results show that the films behave as an n-type semiconductor with shallow and deep donor levels situated in the forbidden gap. The presence of copper seems to affect the density of the shallow and of the deep donor levels in the forbidden gap, and as chromium, it also decreases the doping ...

2006-12-05

260

The influence of copper and chromium on the semiconducting behaviour of passive films formed on weathering steels  

International Nuclear Information System (INIS)

The influence of small amounts of alloying elements (0.36% Cu and 0.47% Cr) on the semiconducting properties of passive films formed on weathering steels was investigated either in tetraborate/boric acid buffer solution (pH 9.2) or artificial atmospheric environment (SO_2-containing environment). The electrochemical behaviour was assessed by potentiodynamic polarisation, capacitance measurements and photoelectrochemistry. The chemical characterisation of the films was carried by Auger electron spectroscopy. The polarization results obtained in the buffer solution show that the addition of chromium decreases the passive current density. The capacitance results show that the films behave as an n-type semiconductor with shallow and deep donor levels situated in the forbidden gap. The presence of copper seems to affect the density of the shallow and of the deep donor levels in the forbidden gap, and as chromium, it also decreases the doping density ...

2006-12-05

261

Suitability of filter ash surfaces as locations for plants  

Energy Technology Data Exchange (ETDEWEB)

The possibility of a positive agricultural use of flue gas filter ash from brown coal power plants is investigated. The suggested measure is mixing ash dump surfaces with extremely acidic spoil bank soils, which balances the high pH value of the alkaline ash and contributes to improved nutrient and soil sorptive conditions. Optimum quantity of spoil bank sands in the mixture with ash is between 10% and 40%. The optimum quantity must be determined for each type of ash considering improvement of soil chemical conditions and water retention capacity. Filter ash properties vary widely; the required amount of spoil bank sand added to investigated ash surfaces near 3 brown coal power plants was between 25% and 30% of the mixture. The same favourable soil and ash mixture can be produced by adding 60% to 75% filter ash to acidic raw spoil bank soil surfaces forming a top soil layer in a thickness of minimum 60 cm. Tests of plant growth showed high crop ...

1980-01-01

262

Study of passive films formed on stainless steel surfaces, using Auger spectroscopy  

International Nuclear Information System (INIS)

This paper deals with the characterization of passive films formed on stainless steel (26% Cr and 0 to 3%Mo). The influence of the applied passivation potential and the effect of molybdenum additions to steel upon the composition profiles of passive films formed in an aqueous NaCl solution (3.5% at pH 2.5) are studied. The technique involved is Auger electron spectroscopy combined with ion sputtering. Some electrochemical techniques have been used in conjunction. A quantitative approach of the Auger spectra during the progressive removal of the passive film is described. The peak-to-peak height of the Auger lines are treated in order to yield the atomic fraction of the various elements present in a given subsurface layer. The analytical study of the film by electron spectroscopy indicates that molybdenum plays a part at the metal-oxide interface where this element acts on the chromium diffusion process. This phenomenon, which depends on the imposed potential, may ...

1975-01-01

263

Simultaneous biosorption of chromium(VI) and copper(II) on Rhizopus arrhizus in packed column reactor: Application of the competitive Freundlich model  

Energy Technology Data Exchange (ETDEWEB)

The simultaneous biosorption of Cr(VI) and Cu(II) on free Rhizopus arrhizus in a packed column operated in the continuous mode was investigated and compared to the single metal ion situation. The breakthrough curves were measured as a function of feed flow rate, feed pH, and different combinations of metal ion concentrations in the feed solutions. Column competitive biosorption data were evaluated in terms of the maximum (equilibrium) capacity in the column, the amount of metal loading on the R. arrhizus surface, the adsorption yield, and the total adsorption yield. In the single-ion situation the adsorption isotherms were developed for optimum conditions, and it was seen that the adsorption equilibrium data fit the noncompetitive Freundlich model. For the multicomponent adsorption equilibrium the competitive adsorption isotherms were also developed. The competitive Freundlich model for binary metal mixtures represented most the column ...

1999-12-01

264

Selective adsorption of uranium on activated charcoal from electrolytic aqueous solutions  

Energy Technology Data Exchange (ETDEWEB)

Adsorption of uranium onto various solids is important from purification, environmental, and radioactive waste disposal points of view. Adsorption of uranium on activated charcoal has been studied as a function of shaking time, amount of adsorbent, pH, concentration of adsorbate, and temperature. Uranium adsorption obeys the Langmuir isotherm. {Delta}H{degrees} and {Delta}S{degrees} were calculated from the slope and intercept of plots ln K{sub D} vs 1/T. The influence of different anions and cations on uranium adsorption has been examined. The adsorption of other metal ions on activated charcoal has been studied under specified conditions to check its selectivity; consequently, uranium was removed from Cs, Ba, Zn, and Co. More than 98% adsorbed uranium on activated charcoal can be recovered with 65 ml of 3 M HNO{sub 3} solution. A wavelength dispersive x-ray fluorescence spectrometer was used for measuring uranium concentration.

1992-02-01

265

Potential biogas scrubbing using a high rate pond  

Energy Technology Data Exchange (ETDEWEB)

The potential to scrub biogas in a high rate pond (HRP) was evaluated using apparatus designed to maximize gas-liquid contact. Experiments compared the removal of carbon dioxide from synthetic biogas by an 'in-pond angled gutter' to that by a simulated 'counter-current pit'. Results showed that the counter current pit has potential for use in biogas scrubbing, with synthetic biogas carbon dioxide composition consistently reduced from 40% to<5%. The in-pond angled gutter was less effective due to bubble coalescence which reduced the total bubble surface surface area available for gas transfer. Measurement of oxygen levels in the scrubbed biogas showed that despite supersaturation of oxygen in the HRP water, there was little transfer to the biogas, so that explosive methane/oxygen mixtures would not be formed. Theoretical calculations indicated that the amount of biogas likely to be formed during anaerobic treatment of ...

2005-07-01

266

Nanostructured p-CuIn3Se5/n-CdS heterojunction engineered using simple wet chemical approach at room temperature for photovoltaic application  

British Library Electronic Table of Contents (United Kingdom)

Herein, we report engineering of nanostructured p-CuIn3Se5/n-CdS heterojunction thin film on a glass substrate, which is prepared at room temperature using simple wet chemical approach involving ion exchange reactions between CdS and Cu^+, In^3^+ and Se^2^- ions in alkaline medium. The uniform deposition of heterojunction thin films is achieved by optimizing the pH, temperature and molarity of the reactant bath. The as-deposited thin-films were annealed at 200^oC in air for 1h and further characterized for structural, optical and electrical properties using UV-Vis spectrophotometer, X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), Hall effect for type of conductivity, and I-V measurement to investigate the char...

2011-01-01

267

Mine waste disposal and managements  

Energy Technology Data Exchange (ETDEWEB)

Acid Rock Drainage (ARD) is the product formed by the atmospheric oxidation of the relatively common pyrite and pyrrhotite. Waste rock dumps and tailings containing sulfide mineral have been reported at toxic materials producing ARD. Mining in sulphide bearing rock is one of activity which may lead to generation and release of ARD. ARD has had some major detrimental affects on mining areas. The purpose of this study was carried out to develop disposal method for preventing contamination of water and soil environment by waste rocks dump and tailings, which could discharge the acid drainage with high level of metals. Scope of this study was as following: environmental impacts by mine wastes, geochemical characteristics such as metal speciation, acid potential and paste pH of mine wastes, interpretation of occurrence of ARD underneath tailings impoundment, analysis of slope stability of tailings dam etc. The following procedures were used as part of ARD evaluation and ...

1998-12-01

268

In-Situ Analysis of Electronic Properties of Passive Film on Fe by Photo-Electrochemical and Impedance Techniques  

Energy Technology Data Exchange (ETDEWEB)

Electronic properties of passive films formed on Fe at various applied potentials in pH 8.5 buffer solution were examined through the photocurrent measurement and impedance spectroscopy. Passive film formed on Fe at relatively low potentials was found to be r-FeOOH layer and internal r-Fe{sub 2}O{sub 3} layer. However, the r-FeOOH layer became unstable and disappeared at potentials below 400mV and hence may be an adsorbed layer. An electronic band structure model for the passive film of Fe was suggested on the basis of the spinel band model with involving two types of electronic excitation processes, i. e., the p-d and the d-d transition together. The effects of applied potential on the photocurrent behaviors of the passive film on Fe were explained appropriately by separating the photocurrent spectra depending on the transition type. The Mott-Schottky behavior for the passive film on Fe and the photocurrent variation with applied potential ...

1999-04-01

269

Fatigue crack growth in steam turbine rotor steels in near realistic media  

International Nuclear Information System (INIS)

In this study, growth measurements of fatigue cracks in air and various simulated media for steam turbines were made by means of rupture-mechanical methods. In this connection, it was detected that even pure water leads to a clear increase in the fatigue crack rates of low-pressure rotor steels. In this connection, it was striking to observe that the crack propagation velocities at 100"0C were higher than at 160"0C. It is probable that the kinetics of the film formation at the crack tip was of importance. The inhibiting effect of the alkaline solutions is explained by the increasing stability of a film of Fe(OH)_2 at an increased pH value. Neither the frequency response nor the fractographic result indicate an influence of the stress crack corrosion. This can be explained by the fact that the incubation period (= the period to initiate an intercrystalline crack caused by stress crack corrosion at a transcrystalline fatigue crack tip) in the ...

1988-03-17

270

Effect of dissolved oxygen, hydrazine and pH outside the crevice on the galvanic corrosion of support plate alloys  

International Nuclear Information System (INIS)

A study has been performed of the initial corrosion of support structure alloys in crevices of various geometries, when galvanically coupled to alloy 600. Corrosion rates were monitored continuously by measuring the galvanic current flowing in each couple, transduced by a zero impedance ammeter. Experiments were performed in a single-pass flowing electrolyte system, with AVT water pumped through alloy 600 tubing past the orifice of each crevice. Fourteen crevices were studied simultaneously in two parallel flow arms containing seven specimens each. The steady state AVT water pH/hydrazine/oxygen concentrations were controlled by microcomputer, allowing the effect of secondary water chemistry on the corrosion rate to be studied easily. Control of the crevice electrolyte composition was achieved by separately pumping electrolyte, at a low rate, directly into the crevices of the seven specimens in the lower flow arm. In addition, a high pressure syringe was used to ...

1985-03-01

271

Development program for magnetically assisted chemical separation: Evaluation of cesium removal from Hanford tank supernatant  

International Nuclear Information System (INIS)

Magnetic particles (MAG*SEP"S"M) coated with various absorbents were evaluated for the separation and recovery of low concentrations of cesium from nuclear waste solutions. The MAG*SEP"S"M particles were coated with (1) clinoptilolite, (2) transylvanian volcanic tuff, (3) resorcinol formaldehyde, and (4) crystalline silico-titanate, and then were contacted with a Hanford supernatant simulant. Particles coated with the crystalline silico-titanate were identified by Bradtec as having the highest capacity for cesium removal under the conditions tested (variation of pH, ionic strength, cesium concentration, and absorbent/solution ratio). The MAG*SEP"S"M particles coated with resorcinol formaldehyde had high distribution ratios values and could also be used to remove cesium from Hanford supernant simulant. Gamma irradiation studies were performed on the MAG*SEP"S"M particles with a gamma dose equivalent to 100 cycles of use. This irradiation decreased the loading ...

1994-05-09

272

Continuous monitoring of conventional parameters to assess receiving water quality in support of combined sewer overflow abatement plans.  

Science.gov (United States)

As part of its long-term control plan for combined sewer overflow (CSO) abatement, the city of Buffalo, New York, maintained a network of Hydrolab Datasondes (Hydrolab-Hach Company, Loveland, Colorado) to assess receiving water-quality effects by continuously logging dissolved oxygen, pH, temperature, conductivity, and turbidity. Although the effect of individual CSOs could be visualized, turbidity levels entering the Buffalo River from the upper watershed often were greater than from CSO discharges. Turbidity data showed that the Buffalo River was a net-sediment sink. Low dissolved oxygen levels were observed in the summer during dry weather, baseflow, and watershed-wide storms and CSO events. Some CSOs did not produce dissolved oxygen sags in the receiving waters, but others did. This information, together with the sampling done for organic and inorganic contaminants, can aid the decisionmaking process when prioritizing outfalls for abatement work and provides a ...

273

Anodic stripping voltammetric determination of uranium at a thin palladium film-aluminum electrode. Analysis of some uranium mineral ores  

International Nuclear Information System (INIS)

In the present work, a rapid deposition anodic stripping voltammetry (ASV) for determination of uranium is presented. For this purpose, the uranyl hexacyanoferrate (K2UO2[Fe(CN)6]) is deposited electrochemically on a thin palladium-aluminum electrode (Pd-Al) from a UO22+ solution in the presence of K3Fe(CN)6. Then, the well stable (K2UO2[Fe(CN)6]) on the electrode was stripped by anodic differential pulse voltammetry for measuring the UO22+ ion concentration. The effect of operational parameters, including: concentration of K3Fe(CN)6, solution pH, deposition potential, and deposition time were studied. In optimum conditions, the calibration graph was linear in the concentration range 105-7 x 10-4 mol L-1 with a detection limit of 6.2 x 10-6 mol L-1. The influence of some concomitant ions in K2UO2[Fe(CN)6] formation was investigated. The proposed method was used for the rapid determination of uranium in some uranium mineral ores. (orig.)

2010-01-01

274

Use of a point-of-care beta-hydroxybutyrate sensor for detection of ketonemia in dogs.  

Science.gov (United States)

The urine test strip is the most common test used to detect ketones in veterinary patients, but it can underestimate the degree of ketonuria and hence, ketonemia. Additionally, adequate urine samples for analysis may be difficult to obtain from dehydrated animals. The standard method used to detect and monitor ketonemia in human medicine is measurement of serum or whole blood beta-hydroxybutyrate (?HOB). A point-of-care (POC) analyzer has been validated for this purpose in humans. This study compared the accuracy of the POC device to an enzymatic reaction laboratory method for measurement of ?HOB in dogs. Although the POC sensor tended to overestimate ?HOB concentrations, there was good correlation (R(2) = 0.96) and good agreement between the 2 methods with a bias +/- precision of 0.0860 +/- 0.3410 mmol/L ?HOB. The POC ?HOB sensor can be useful for assessing ketonemia in dogs. PMID:21119867

2010-09-01

275

Unitary constraints on Deeply Virtual Compton Scattering  

Energy Technology Data Exchange (ETDEWEB)

At moderately low momentum transfer ($-t$ up to 1 GeV$^2$) the coupling to the vector meson production channels gives the dominant contribution to real Compton and deeply virtual Compton scattering (DVCS). Starting from a Regge Pole approach that successfully describes vector meson production, the singular part of the corresponding box diagrams (where the intermediate vector meson-baryon pair propagates on-shell) is evaluated without any further assumptions (unitarity). Such a treatment explains not only the unexpectedly large DVCS unpolarized cross section that has been recently measured at Jefferson Laboratory (JLab), but also all the beam spin and charge asymmetries that has been measured at JLab and Hermes, without explicit need of Generalized Parton Distributions (GPD). The issue of the relationship between the two approaches is addressed.

2007-11-01

276

Ultraviolet-B Phototoxicity and Hypothetical Photomelanomagenesis: Intraocular and Crystalline Lens Photoprotection  

British Library Electronic Table of Contents (United Kingdom)

Purpose Ultraviolet-B (UV-B) radiation can cause phototoxic macular injuries in young people who have been sunbathing but not sungazing and in welders. Welders have a reportedly increased risk of uveal melanoma. We analyze phakic and pseudophakic risks for solar and welding arc UV-B exposure. Design Optical radiation measurement, analysis, and perspective. Methods Spectral transmittances were measured for UV-transmitting, UV-blocking, and blue-blocking intraocular lenses (IOLs). The photoprotective performances of crystalline and intraocular lenses were analyzed using relevant epidemiologic and laboratory data and action spectra for acute retinal phototoxicity and melanoma photocarcinogenesis. Results Crystalline lens UV-B retinal protection is deficient in children and young adults, incre...

2010-01-01

277

Surface characteristics and overlaying properties of flat-pressed wood plastic composites  

British Library Electronic Table of Contents (United Kingdom)

This study evaluated surface characteristics and overlaying properties of wood plastic composite (WPC) panels made from dry-blended rubber wood fiber-polypropylene (PP) powder formulations using a conventional flat-press process under laboratory conditions. Three levels of rubberwood fibers (Hevea brasiliensis), 40%, 50%, and 60%, based on the composition by weight, were mixed with the PP powder without and with 3% (based on weight) maleic anhydride grafted PP (MAPP) as a coupling agent. Contact angle measurements on the WPC samples were performed using a goniometer connected with a digital camera which collected one image per second. Roughness measurements, average roughness (R a), mean peak-to-valley height (R z), and maximum roughness (R y), were taken from the sanded samples along and ...

2011-01-01

278

Strain gauge validation experiments for the Sandia 34-meter VAWT (Vertical Axis Wind Turbine) test bed  

Science.gov (United States)

Sandia National Laboratories has erected a research oriented, 34- meter diameter, Darrieus vertical axis wind turbine near Bushland, Texas. This machine, designated the Sandia 34-m VAWT Test Bed, is equipped with a large array of strain gauges that have been placed at critical positions about the blades. This manuscript details a series of four-point bend experiments that were conducted to validate the output of the blade strain gauge circuits. The output of a particular gauge circuit is validated by comparing its output to equivalent gauge circuits (in this stress state) and to theoretical predictions. With only a few exceptions, the difference between measured and predicted strain values for a gauge circuit was found to be of the order of the estimated repeatability for the measurement system.

1988-08-01

279

Relationships of radon diffusion coefficient with saturated hydraulic conductivity, fines content and moisture saturation of radon/infiltration barriers for the UMTRA Project  

Energy Technology Data Exchange (ETDEWEB)

The release of {sup 222}Radon to the atmosphere is controlled by the rate of its gas transport through earthen materials. Of the many soil-related parameters, radon diffusion coefficient is the key parameter that characterizes this transport. We compared the radon diffusion coefficients measured at the laboratories for the UMTRA Project with simple empirical correlations developed by others. The empirical correlations predict the radon diffusion coefficient based on the fraction of moisture saturation and porosity. One of the more recent correlations agrees reasonably well with the measurements. In addition, by using a series of correlation curves, we studied the empirical relationships of the. radon diffusion coefficient with the saturated hydraulic conductivity, the fines content, and the moisture saturation in soil. The results reveal that a reliable determination of the long-term moisture and porosity is essential in ...

1994-01-24

280

Quality control and evaluation for environmental radiological baseline study of Guangdong Daya Bay nuclear power station  

International Nuclear Information System (INIS)

The main points of quality control methods and technique of environmental radiological baseline study of Guangdong Daya Bay Nuclear Power Station are reported. Results of intercalibration of international and inland laboratories are given. The random chosen samples are checked and compared with two measurement methods. The data obtained in Daya Bay environment are put to the correlation statistics test using the linear regression analysis method between the correlative items such as "4"0K activity by gamma spectrum measurement and potassium content by chemical analysis, total #alpha#(#beta#) activity and nuclide content, as well as environmental gamma radiation dose rate and TLD accumulation dose. The data of Daya Bay environmental radioactivity baseline level show good concordance and reliability.

281

Measurements to be taken after a nuclear accident in order to limit the uptake of radionuclides from the soil by nutrition crops  

International Nuclear Information System (INIS)

By the department Radio-ecology of the Laboratory for Radiation Research, in the period 1981 up to 1989 inclusive, the transfer has been studied, from soil to plant, of a number of important activation and fission products, originating in the nuclear-power production in nuclear power plants. The purpose of this study was twofold: on the one side the quantification of this transfer for various agrarian systems and on the other side to find out in how far, after an accidental contamination, certain agriculture activities can influence essentially the transfer and subsequently the radiation burden for the population. Emphasis lay, the last years, in particular upon this second aspect. The results of this study form essential basic data for diffusion models for radioactive materials which, in turn, are important in estimating the effects of measures. (author). 6 refs.; 4 figs.

282

Measurement of beta-decay half-lives of short-lived nuclei with Spectrum Multi-Scaler (SMS)  

Energy Technology Data Exchange (ETDEWEB)

The half-lives of short-lived nuclei produced by 14 MeV or thermal neutron bombardments were measured with a Ge detector, a Spectrum Multi-Scaler (Laboratory Equipment Corporation SMS-48) and a High-Rate Spectroscopy Amplifier (EG and G ORTEC Model 973) in the multi-scaling mode. The corrections for pile-up and dead-time losses were performed by applying source and pulser methods. The half-lives of {sup 91m}Mo, {sup 97m}Nb, {sup 138}Cs, {sup 139}Ba, {sup 174}Tm and {sup 203m}Pb were determined with accuracy of 0.22-0.6% and the accuracy has been much improved. (author)

1996-03-01

283

Indoor climate seminar; Sisaeilmastoseminaari  

Energy Technology Data Exchange (ETDEWEB)

The national energy research programme LVIS-2000: Future Building Services is concerned with the control of energy use and indoor climate in buildings of the future. The projects were presented at a one day seminar arranged by the Laboratory of Heating and Ventilation of the Technical Research Centre in Finland which is coordinating the programme. The presentations at the seminar were: Impurity emission from materials, Building materials and indoor air quality, analysis of organic compounds in indoor air, effect of the return air, effect of the return air on health and comfort, electric heating as an indoor climate factor, calculations of air flows in ventilated rooms, effect of energy saving measures on hospital hygiene, application of modern aerosol measurement technique on indoor climate research.

1989-12-31

284

Emittance of boehmite and alumina films on 6061 aluminium alloy between 295 and 773 K  

International Nuclear Information System (INIS)

The total hemispherical emittance of an oxide film that formed on 6061-T6 aluminium alloy parts in the Tower Shielding Reactor-II at Oak Ridge National Laboratory was measured from 295 to 773 K using an emissometer and/or a calorimeter. The emittance of this film was critically needed for heat transfer calculations in a simulated loss-of-coolant accident of the reactor. X-ray diffraction analysis identified the film as boehmite (Al_2O_3 x H_2O), which dehydrated to alumina (Al_2O_3) upon heating above 473 K. The measured emittances for the alumina film are in excellent agreement with published values for anodized aluminum films and for bulk alumina. Published values of the emittance of boehmite could not be found for comparison, but evidence is presented that some anodization processes for aluminum yield boehmite and not alumina films.

1991-01-01

285

Eluates from pyrolysed refuse. Eluate aus pyrolysiertem Hausmuell  

Energy Technology Data Exchange (ETDEWEB)

The solubility behavior of solid residues from the heat treatment of domestic rubbish was examined by simulated precipitation in laboratory lysimeters. The precipitation corresponded to the average amount of rain in West Germany and was applied at different time periods. Specific soil characteristics, the value of k/sub f/ and the water retention capacity was determined in this way. In parallel with the lysimeter flood ions, extraction (by batch process) was done, in order to find the maximum solubility of the materials used. It was found that for pyrolysis residues from reactor temperatures of 450/sup 0/ to 1000/sup 0/C, a greater solubility was measured than for slag from combustion. The eluates from these residues gave information about the degree of contamination or on the solubility of the measured parameters and materials in organoleptic, physical, organic and inorganic examinations. The concentrations of harmful ...

1981-01-01

286

Design properties of coal liquids: edited workshop proceedings  

Science.gov (United States)

The advent of synfuels will require a large measurement and modeling effort of new thermodynamic and physical properties. These data are required for the economic design and operation of proposed synfuel plants. The areas of data need are well defined. The pace of measurement will be restricted by laboratory availability. The cost for the required data and for their correlation and modeling will be substantial. And finally, the cost of doing all this work will be substantial. The plants we are talking about are energy plants and synfuel plants. They are energy intensive plants, and as such, they offer the prospects for a great deal of energy saving. To do so requires good data. In those critical areas where we start hunting the energy hogs, we will find that with +-20% data those hogs are pretty well hidden.

1981-08-01

287

Deep inelastic scattering of leptons on nuclei  

International Nuclear Information System (INIS)

Experimental studied of deep-inelastic scattering of neutrino, antineutrino, #mu#-mesons, electron reactions on He, D, Al, Fe, Au, Be, C, Ca, Ag, N nuclei conducted in recent years at different laboratories the world for consideration of modern status of the problems of R(x, Q"2) = #sigma#sub(L)/#sigma#sub(T) parameter variation and for study on nuclear effects in structural functions of nucleons are described in the review. Experimental information on measurements of the R parameter by data on EMS and SLAK groups is analyzed. It is noted that experimental data on measuring R contain essential errors that hampers unambiguous interpretation of data on nucleon structure. Present experimental data and predictions for explanation of the EMS effect are analyzed from the view point of quark and flucton models of a nucleus.

1984-06-19

288

A method for measuring effective radon diffusion coefficients in radon barriers by using modified Lucas cells  

Energy Technology Data Exchange (ETDEWEB)

Radon proof barriers are used for lowering of radon transport from the soil into the house and the determination of the radon diffusion coefficient is an important parameter to be determined in order to design the minimal thickness of the radon proof insulation. A method has been developed in our laboratory by using modified Lucas cells connected to a radon source and tightly closed onto the top by the tested membranes whose radon diffusion coefficients are being measured. Solving the time-dependent differential equation for radon diffusion in the membrane for well-defined experimental conditions the effective radon diffusion coefficient of the insulating material can be evaluated by comparing the radon concentration decrease in the cell for the first hours with the well-known radioactive decay. First results obtained in several preliminary tests carried out with a parafilm M barrier and two polyethylene membranes are shown in this paper.

2005-01-01

289

NRL Fact Book 2010  

Science.gov (United States)

... Tactical Electronic Warfare Division (Code 5700) Visualization Laboratory Transportable step frequency radar Vehicle development laboratory ...

2011-05-15

290

NRL Fact Book  

Science.gov (United States)

... Tactical Electronic Warfare Division (Code 5700) Visualization Laboratory Transportable step frequency radar Vehicle development laboratory ...

2011-05-15

291

Preliminary study of the {alpha} ratio measurement, ratio of the neutron capture cross section to the fission one for {sup 233}U, on the PEREN platform. Development and study of the experimental setup; Etude preliminaire de la mesure du rapport {alpha}, rapport de la section efficace moyenne de capture sur celle de fission de l'{sup 233}U, sur la plateforme PEREN. Developpement et etude du dispositif experimental  

Energy Technology Data Exchange (ETDEWEB)

Producing nuclear energy in order to reduce anthropic CO{sub 2} emission and to meet high energy demand, implies three conditions to the nuclear plants of the IV. generation: safety improvements, radioactive waste minimization, and fuel breeding for a sustainable use of the resources. The Thorium fuel cycle used in Molten Salt Reactors seems promising. Many numerical studies based on probabilistic codes are carried out in order to analyse the behaviour of such reactors. Nevertheless, one of the most important parameters is badly known: the alpha ratio of {sup 233}U, ratio of the neutron capture cross section to fission one for {sup 233}U. This key-parameter is necessary to calculate the breeding ratio and thus, the deployment capacities of those reactors. This Ph-D thesis was intended to prepare a precise measurement of the alpha ratio of {sup 233}U between 1 eV and 10 keV. Preliminary measurements have been performed on ...

2007-12-15

292

Optical diagnostics for turbulent and multiphase flows: Particle image velocimetry and photorefractive optics  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the work performed under the Sandia Laboratory Directed Research and Development (LDRD) project ``Optical Diagnostics for Turbulent and Multiphase Flows.`` Advanced optical diagnostics have been investigated and developed for flow field measurements, including capabilities for measurement in turbulent, multiphase, and heated flows. Particle Image Velocimetry (PIV) includes several techniques for measurement of instantaneous flow field velocities and associated turbulence quantities. Nonlinear photorefractive optical materials have been investigated for the possibility of measuring turbulence quantities (turbulent spectrum) more directly. The two-dimensional PIV techniques developed under this LDRD were shown to work well, and were compared with more traditional laser Doppler velocimetry (LDV). Three-dimensional PIV techniques were developed and tested, but due ...

1997-01-01

293

Measuring head for radionuclide X-ray fluorescence analyzer  

International Nuclear Information System (INIS)

The design of a gaging head for a portable radionuclide X-ray fluorescence analyzer is described. The gaging head is designed as a construction unit system which enables the application of lateral reflexion geometry as well as of coaxial geometry. It is designed so that adjustment from one geometry to the other is labour and time saving. The selection of characteristic radiation is performed by a couple of Ross' differential filters. These filters are prepared by a novel technique developed by our laboratory. The filter exchange is effected by the longitudinal move of the couple of filters encapsulated in a holder. The shift of the filters is controlled by means of a triggering mechanism situated in the body of the gaging head handle. This design makes is possible to handle the gaging head during measurements with one hand. A simple interchange of the absorption filter for the transmissive filter allows the operator to avoid any unwanted shift ...

1976-05-21

294

Measurement of cumulative-photon spectra at high transverse momenta in 12C 9Be interactions at an energy of 3.2 GeV per nucleon  

International Nuclear Information System (INIS)

For 12C 9Be interactions at a kinetic beam energy of 3.2 GeV per nucleon, the spectra of photons at laboratory angles in the range 55o-73o were measured off the kinematical region available to the interaction of single nucleons within colliding nuclei. The use of a fast trigger for selecting events involving the production of high-transverse-momentum photons made it possible to measure spectra off the kinematical boundary of four-nucleon interaction. It is shown that the proposed procedure is adequate to the problem of searches for and investigation of flucton-flucton interaction. In the kinematical region where flucton-flucton interaction can manifest itself, the cross sections in question are on the same order of magnitude as respective model predictions. In order to draw definitive conclusions on the role of flucton-flucton interaction, it is highly desirable to extend the angular range of the ...

2008-11-01

295

Indoor and outdoor Radon concentration measurements in Sivas, Turkey, in comparison with geological setting  

Energy Technology Data Exchange (ETDEWEB)

Indoor and soil gas Radon ({sup 222}Rn) concentration measurements were accomplished in two stages in Sivas, a central eastern city in Turkey. In the first stage, CR-39 passive nuclear track detectors supplied by the Turkish Atomic Energy Authority (TAEA) were placed in the selected houses throughout Sivas centrum in two seasons; summer and winter. Before the setup of detectors, a detailed questionnaire form was distributed to the inhabitants of selected houses to investigate construction parameters and properties of the houses, and living conditions of inhabitants. Detectors were collected back two months later and analysed at TAEA laboratories to obtain indoor {sup 222}Rn gas concentration values. In the second stage, soil gas {sup 222}Rn measurements were performed using an alphameter near the selected houses for the indoor measurements. Although {sup 222}Rn concentrations in Sivas were quite low in ...

2010-11-15

296

Comparison of methods to measure the rate of neutral free radical production by photo-deionization of negative ion beams  

Energy Technology Data Exchange (ETDEWEB)

Two measurement methods to determine the rate of neutral free radical production by the photo-deionization of negative ion beams (PDINIB) are introduced. These methods, namely, photoelectron-current measurement by low-frequency electro-modulation probe (PMMP) and measurement of decrease in the negative-ion beam current (DNIC) were employed to evaluate the production rate in a trial surface-processing apparatus developed in the author's laboratory utilizing a steady-flux refined beam of neutral free radicals (RBNR) produced by the PDINIB procedure. A {sup 63}Cu{sup -} negative ion beam of kinetic energy E{sub i} varied up to 15 keV was irradiated with a 514.5 nm visible light beam from a 25 W CW Ar{sup +} ion laser. The detection limit of the production rate by the PMMP setup was as high as 6 x 10{sup 9} s{sup -1} under the condition that E{sub i}=15 keV, the negative-ion beam current I{sub i}=4 ...

2003-05-01

297

Sandia National Laboratories/California site environmental report for 1997  

Energy Technology Data Exchange (ETDEWEB)

Sandia National Laboratories (SNL) is committed to conducting its operations in an environmentally safe and sound manner. It is mandatory that activities at SNL/California comply with all applicable environmental statutes, regulations, and standards. Moreover, SNL/California continuously strives to reduce risks to employees, the public, and the environment to the lowest levels reasonably possible. To help verify effective protection of public safety and preservation of the environment, SNL/California maintains an extensive, ongoing environmental monitoring program. This program monitors all significant effluents and the environment at the SNL/California site perimeter. Lawrence Livermore National Laboratory (LLNL) performs off-site external radiation monitoring for both sites. These monitoring efforts ensure that emission controls are effective in preventing contamination of the environment. As part of SNL/California`s Environmental Monitoring ...

1998-06-01

298

Hydrogeology and tritium transport in Chicken Creek Canyon,Lawrence Berkeley National Laboratory, Berkeley, California  

Energy Technology Data Exchange (ETDEWEB)

This study of the hydrogeology of Chicken Creek Canyon wasconducted by the Environmental Restoration Program (ERP) at LawrenceBerkeley National Laboratory (LBNL). This canyon extends downhill fromBuilding 31 at LBNL to Centennial Road below. The leading edge of agroundwater tritium plume at LBNL is located at the top of the canyon.Tritium activities measured in this portion of the plume during thisstudy were approximately 3,000 picocuries/liter (pCi/L), which issignificantly less than the maximum contaminant level (MCL) for drinkingwaterof 20,000 pCi/L established by the Environmental ProtectionAgency.There are three main pathways for tritium migration beyond theLaboratory s boundary: air, surface water and groundwater flow. Thepurpose of this report is to evaluate the groundwater pathway.Hydrogeologic investigation commenced with review of historicalgeotechnical reports including 35 bore logs and 27 test pit/trench logsas ...

2007-10-31

299

Air quality monitoring Lloydminster area : 2002, 2003 and 2004 seasonal monitoring : final report  

Energy Technology Data Exchange (ETDEWEB)

As part of its air quality monitoring activities, Alberta Environment conducts unannounced mobile air quality surveys each year using the Department's Mobile Air Monitoring Laboratory (MAML). This laboratory provides a snapshot of the air quality at the location monitored for a particular time and space. The MAML measures several pollutants in the air including ammonia, carbon monoxide, hydrocarbons, oxides of nitrogen, ozone, particulate matter, reduced sulphur compounds and sulphur dioxide. Alberta Environment conducted a series of ambient air quality monitoring surveys in the Lloydminster Area in 2002, 2003 and 2004. This report presents the results of the five monitored locations over eight seasons of monitoring, which were selected in consultation with stakeholders and staff from Alberta Environment's Central Region office. Canister samples were also collected during these surveys for later ...

2005-11-01

300

Dosimetric Implications of Atmospheric Dispersal of Tritium Near a Heavy-water Research Reactor Facility  

Energy Technology Data Exchange (ETDEWEB)

An estimate of the tritium dose to the public in the vicinity of the heavy water research reactor facility at AECL-Chalk River Laboratories, Ontario, Canada, has largely been accomplished from analyses on regularly-collected samples of air, precipitation, drinking water and foodstuffs (pasture, fruit, vegetables and milk) and environmental dose models. To increase the confidence with which public doses are calculated, tritium doses were estimated directly from the ratio of tritiated species in urine samples from members of the general public. Single cumulative 24 h urine samples from a few adults living in the vicinity of the heavy-water research reactor facility at Chalk River Laboratories, Canada were collected and analysed for tritiated water and organically bound tritium. The participants were from Ottawa (200 km east), Deep River (10 km west) and Chalk River Laboratories. Tritiated water concentrations in urine ranged ...

2001-07-01

301

Future needs and requirements for AMS "1"4C standards and reference materials  

International Nuclear Information System (INIS)

"1"4C measurement uses a number of standards and reference materials with different properties. Historically the absolute calibration of "1"4C measurement was tied to 1890 wood, through the 'primary' standard of NBS-OxI (produced by the National Bureau of Standards, now NIST - National Institute of Standards and technology) subsequently replaced by NBS-OxII. These are both internationally calibrated and certified materials, whose "1"4C activities are known absolutely. A second tier of materials, often called secondary standards or reference materials, and including internationally recognised materials such as ANU-sucrose (now also IAEA-C6), Chinese - sucrose and the IAEA C1-C6 series, augmented by additional oxalic acid samples are also used routinely. The activity of these materials has been estimated from large numbers of measurements made by many laboratories. Recently, further natural materials from ...

2004-08-01

302

[Determination of glucose, proteins, blood and leucocytes in urines: evaluation of automated analyzer Aution Max AX 4280].  

Science.gov (United States)

The aim of this study was to evaluate the automated urine test strip analyzer Aution Max AX 4280 which uses strips able to measure 12 urinary parameters. For precision study, we considered glucose, protein, blood, leukocytes, nitrite, and pH and the four first were compared with usual methods: chemical measurement or microscopic examination. Reproducibility of the semi quantitative results was determined as the proportion of results falling into the same concentration range. Within-run reproducibility assessed using urine specimens were between 83% and 96%. Between day on quality controlled materials, it was higher (96%), and leukocytes were shared between two classes 250 and 500 cells/microL. For glucose and proteins, linearity was good and comparison with quantitative methods yielded high correlation. The false negative fraction was low and there was no false positive results. For blood, fraction of false positive was ...

303

Study of ytterbium doping effects on structural, mechanical and opto-thermal properties of sprayed ZnO thin films using the Boubaker Polynomials Expansion Scheme (BPES)  

Energy Technology Data Exchange (ETDEWEB)

In this work, ZnO thin films have been grown on glass substrates by using a solution of propanol (C{sub 3}H{sub 8}O), water (H{sub 2}O) and zinc acetate (Z{sub n}(CH{sub 3}CO{sub 2}){sub 2}) in acidified medium (pH 5). The obtained films were n doped with ytterbium (Yb) at the rates of 100, 200 and 300 ppm. The structural features of the doped films were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. XRD analysis shows a strong (0 0 2) X-ray diffraction line for increasing Yb-doping amounts. This c-axis preferential orientation of ZnO crystallites is naturally required to use this oxide as transparent conductor in optoelectronic applications. Atomic force microscopy (AFM) analysis shows an enhancement in the surface roughness of the doped ZnO:Yb thin films. Optical measurements were performed in 300-1800 nm domain via transmittance T(lambda) and reflectance R(lambda) spectra. Conjoint optical and ...

2009-10-19

304

Study of ytterbium doping effects on structural, mechanical and opto-thermal properties of sprayed ZnO thin films using the Boubaker Polynomials Expansion Scheme (BPES)  

International Nuclear Information System (INIS)

In this work, ZnO thin films have been grown on glass substrates by using a solution of propanol (C3H8O), water (H2O) and zinc acetate (Zn(CH3CO2)2) in acidified medium (pH 5). The obtained films were n doped with ytterbium (Yb) at the rates of 100, 200 and 300 ppm. The structural features of the doped films were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. XRD analysis shows a strong (0 0 2) X-ray diffraction line for increasing Yb-doping amounts. This c-axis preferential orientation of ZnO crystallites is naturally required to use this oxide as transparent conductor in optoelectronic applications. Atomic force microscopy (AFM) analysis shows an enhancement in the surface roughness of the doped ZnO:Yb thin films. Optical measurements were performed in 300-1800 nm domain via transmittance T(?) and reflectance R(?) spectra. Conjoint optical and thermal properties were deduced from the optical ...

2009-10-19

305

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 ...

2008-12-15

306

Origin of {gamma}-rays from young open clusters  

Energy Technology Data Exchange (ETDEWEB)

The young open cluster Berkeley 87 was predicted to be associated with the COS B {gamma}-ray source 2CG 075+00 on the basis of the experimental evidence of the presence of a shock front around the Wolf - Rayet star ST3 placed in the inner part of the cluster. The CGRO phase-1 data confirm this identification. Protons accelerated at the shock boundary can produce {pi} deg. via p-p interactions and then {gamma}-rays. With the measured flux F{sub {gamma}} (E > 100 MeV) {approx_equal} 9x10{sup -7} ph cm{sup -2} s{sup -1} and the power-law proton spectrum with spectral index {gamma} = 2, the cosmic-ray-energy-density in the inner part ({approx} 0.8 pc radius) of Berk 87 is about 100 times greater than that in the vicinity of the Earth. We have calculated {gamma}-ray spectra expected from the decay of {pi}{sup d}eg. produced in p-p interactions. The spectra have been normalized to the observed flux of Berk 87 by using different input proton ...

1996-08-01

307

Operational experiences with cathodic protection of Statoil's main onshore pipelines: a description of the online monitoring systems  

Energy Technology Data Exchange (ETDEWEB)

Statoil is operating an increasing number of offshore and onshore pipelines in the North Sea area and elsewhere. Cathodic protection is a significant part of the corrosion management for these lines and we have collected a significant amount of experience with respect to design and operation of the systems. This paper deals with our comprehensive program for the onshore cathodic protection systems and the various challenges in different countries with respect to technical matters, such as operating conditions and different terrain. Generally, the systems are based on automatically controlled rectifier systems with a wide range of current drainage and very comprehensive monitoring of potentials and current flowing. The use of coupons, polarisation cells and buried reference cells are essential, as well as the use of intensive measurements along the route. The use of online monitoring of selected test posts and all rectifier units is considered essential for remote ...

1999-07-01

308

Methods and results for calibration and track separation of a GEM based TPC using an UV-laser  

Energy Technology Data Exchange (ETDEWEB)

In the last 30 years high energy physics could write an impressive story of success. Since the introduction of the Standard Model (SM), it has met every experimental test. However the final confirmation has to prove the mechanism of electroweak symmetry breaking, which could not be confirmed yet. The most favored theory, which includes the introduction of a Higgs field, could not be verified experimentally. Furthermore there is clear evidence, that the SM is only a low energy description of nature and its principles, as the SM describes only 4 % of the known matter in the universe. There are two different approaches in accelerator driven high energy physics to clarify the open questions. The Large Hadron Collider (LHC) have a good opportunity to measure some of the missing pieces with its high center of mass energy. The International Linear Collider (ILC) will then measure their parameters with high precision. To guarantee this high precision ...

2008-12-15

309

Winter study of power plant effects  

Energy Technology Data Exchange (ETDEWEB)

As a part of DOE's Meteorological Effects of Thermal Energy Releases (METER) program a field study was undertaken at the Bowen Electric Generating Plant (Plant Bowen) in December 1979. The study was a joint endeavor of Battelle Pacific Northwest Laboratories (PNL), Pennsylvania State University (PSU), and Oak Ridge National Laboratory (ORNL) with the main objective of determining the effects of the plant's smokestack effluents on aerosol characteristics and precipitation chemistry. Other objectives included studies of cooling tower temperature and humidity (T/h) plumes and drift drop concentrations. Conducted over a period of three weeks, the study involved an instrumented aircraft, pilot balloons, a tethered balloon system, a dense network of wetfall chemistry collectors and numerous ground- and tower-based meteorological instruments. Rainfall samples collected during the precipitation event of December 13, 1979, revealed ...

1980-10-01

310

Use of the WNR spallation neutron source at LAMPF to determine the absolute efficiency of a neutron scintillation detector  

Energy Technology Data Exchange (ETDEWEB)

Prompt fission neutron spectrum measurements at the University of Massachusetts Lowell 5.5 MV Van de Graaff accelerator laboratory require that the neutron detector efficiency be well known over a neutron energy range of 100 keV to 20 MeV. The efficiency of the detector, has been determined for energies greater than 5.0 MeV using the Weapons Neutron Research (WNR) white neutron source at the Los Alamos Meson Physics Facility (LAMPF) in a pulsed beam, time-of-flight (TOF) experiment. Carbon matched polyethylene and graphite scatterers were used to obtain a hydrogen spectrum. The detector efficiency was determined using the well known H(n,n) scattering cross section. Results are compared to the detector efficiency calculation program SCINFUL available from the Radiation Shielding Information Center at Oak Ridge National Laboratory.

1994-06-01

311

Theoretical and experimental investigation of thermohydrologic processes in a partially saturated, fractured porous medium  

Energy Technology Data Exchange (ETDEWEB)

The performance of a geologic repository for high-level nuclear waste will be influenced to a large degree by thermohydrologic phenomena created by the emplacement of heat-generating radioactive waste. The importance of these phenomena is manifest in that they can greatly affect the movement of moisture and the resulting transport of radionuclides from the repository. Thus, these phenomena must be well understood prior to a definitive assessment of a potential repository site. An investigation has been undertaken along three separate avenues of analysis: (i) laboratory experiments, (ii) mathematical models, and (iii) similitude analysis. A summary of accomplishments to date is as follows. (1) A review of the literature on the theory of heat and mass transfer in partially saturated porous medium. (2) A development of the governing conservation and constitutive equations. (3) A development of a dimensionless form of the governing equations. (4) A numerical study of ...

1993-07-01

312

Proceedings of the summary seminar within the NKS-B programme 2002-2005[Radioecology  

Energy Technology Data Exchange (ETDEWEB)

This report contains the proceedings of the NKS-B Summary Seminar held on 24-25 October 2005 in Tartu, Estonia. The aim of the seminar was to provide a forum for presenting and discussing the results obtained in the NKS-B programme during the project period 2002 - 2005. The main attention was focused on radioecology and measurement techniques including presentations on the work done in the Projects INDOFERN (New Indicator Organisms for Environmental Radioactivity), LABINCO (Intercomparison of Laboratory Analyses of Radionuclides in Environmental Samples) and ECODOSES (Improving Radiological Assessments of Doses to Humans from Terrestrial Ecosystems). The total number of presentations in the seminar was 27. The seminar was also the final seminar of the four-year INDOFERN Project. The objective of the project was to identify new indicator organisms and biomarkers for assessment of environmental radioactivity in normal and emergency situations. ...

2006-04-15

313

On-line analysis of chemical composition using an FT-Raman spectrometer in the near-ir  

Science.gov (United States)

Newly commercialized Fourier transform Raman spectroscopic instrumentation provides a simpler alternative for vibrational spectroscopic analysis. Instrument vendors currently design for laboratory use, but there are many potential process applications of these stable, easy to use instruments. Raman spectroscopy is highly suited to analysis of aqueous samples. Near infrared excitation minimized fluorescence interference and allows for remote operation via fiber optic probes. The Department of Energy has funded research at the Measurement and Control Center to establish the utility of this method for on-line composition analysis in distillation columns. Laboratory evaluation and instrument employs an air-cooled laser and a thermoelectrically cooled detector. The device is mounted on a three by foot cart for convenient location in control rooms. Current fiber optic extension cables allow for analysis in a cell thirty five ...

1992-01-01

314

Mixed waste solidification testing on polymer and cement-based waste forms in support of Hanford`s WRAP 2A facility  

Energy Technology Data Exchange (ETDEWEB)

A testing program has been conducted by the Westinghouse Hanford Company to confirm the baseline waste form selection for use in Waste Receiving and Processing (WRAP) Module 2A. WRAP Module 2A will provide treatment required to properly dispose of containerized contact-handled, mixed low-level waste at the US Department of Energy Hanford Site in south-central Washington State. Solidification/stabilization has been chosen as the appropriate treatment for this waste. This work is intended to test cement-based, thermosetting polymer, and thermoplastic polymer solidification media to substantiate the technology approach for WRAP Module 2A. Screening tests were performed using the major chemical constituent of each waste type to measure the gross compatibility with the immobilization media and to determine formulations for more detailed testing. Surrogate materials representing each of the eight waste types were prepared in the laboratory. These ...

1993-10-01

315

Investigations of biomimetic light energy harvesting pigments  

Energy Technology Data Exchange (ETDEWEB)

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Nature uses chlorophyll and other porphyrinic pigments to capture and transfer light energy as a preliminary step in photosynthesis. The design of synthetic assemblies of light harvesting and energy directing pigments has been explored through synthesis and characterization of porphyrin oligomers. In this project, pigment electronic and vibrational structures have been explored by electrochemistry and dynamic and static optical measurements. Transient absorption data reveal energy transfer between pigments with lifetimes on the order of 20--200 picoseconds, while Raman data reveal that the basic porphyrin core structure is unperturbed relative to the individual monomer units. These two findings, along with an extensive series of experiments on the oxidized oligomers, reveal that ...

1998-12-01

316

Evaluation of selected elastomer O-ring pump seals for service at the Wilsonville, Alabama, Advanced Coal Liquefaction Research and Development Facility. [Ethylenepropylenediene monomer compounds  

Energy Technology Data Exchange (ETDEWEB)

Previous laboratory tests of elastomer O-rings in coal liquefaction solvents conducted at L'Garde, Inc., indicated that certain ethylenepropylenediene monomer (EPDM) compounds provided the best performance when a backup ring was used to limit swelling. Before service testing in a pump at the Wilsonville, Alabama, Advanced Coal Liquefaction Research and Development Facility, tests of six selected elastomers in the appropriate Wilsonville-produced solvent were conducted at Oak Ridge National Laboratory (ORNL). The ORNL tests measured the elastomers' changes in cross section, weight, density, and relative flexibility. Although two perfluoroelastomers showed less degradation of most properties during these tests, it was decided to proceed with service testing of two EPDM elastomers because of their much lower cost. 5 refs., 14 figs., 7 tabs.

1986-08-01

317

Current status and future plan of JMTR Hot Laboratory  

Energy Technology Data Exchange (ETDEWEB)

The newly developed techniques by the Hot Laboratory (JMTR HL) have provided for us the key information on behavior of specimens due to mechanical / physical / chemical / synergistic effects of radiation, stress and water for fission and fusion reactor environment. These techniques are focused on several topics as follows; (1) miniaturized specimen test for the development of fusion reactor materials, (2) slow strain rate tensile testing (SSRT) and crack propagation measuring tests for the study of Irradiation Assisted Stress Corrosion Cracking (IASCC) of core internals of LWR, (3) handling technique on specimens including tritium for the research and development of tritium breeders and neutron multiplier as fusion blanket materials, (4) joining method using the Tungsten Inert Gas (TIG) welding technique for re-assembling of capsule and re-fabrication of specimen and (5) nondestructive evaluation using ultrasonic wave and infrared thermography ...

1999-08-01

318

Bendable Focusing X-Ray Optics for the ALS and the LCLS/FEL: Design, Metrology, and Performance  

Energy Technology Data Exchange (ETDEWEB)

We review the recent development of bendable x-ray optics used for focusing of beams of soft and hard x-rays at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory and at the Linac Coherent Light Source (LCLS) x-ray free electron laser (FEL) at the Stanford Linear Accelerator Center (SLAC) National Accelerator Laboratory. For simultaneous focusing in the tangential and sagittal directions, two elliptically cylindrical reflecting elements, a Kirkpatrick-Baez (KB) pair, are used. Because fabrication of elliptical surfaces is complicated, the cost of directly fabricated tangential elliptical cylinders is often prohibitive. Moreover, such optics cannot be easily readjusted for use in multiple, different experimental arrangements, e.g. at different focal distances. This is in contrast to flat optics that are simpler to manufacture and easier to measure by conventional interferometry. The tangential figure of ...

2010-06-02

319

A Permeability Model for Coal and Other Fractured, Sorptive-Elastic Media  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the derivation of a new equation that can be used to model the permeability behavior of a fractured, sorptive-elastic media, such as coal, under variable stress conditions commonly used during measurement of permeability data in the laboratory. The model is derived for cubic geometry under biaxial or hydrostatic confining pressures. The model is also designed to handle changes in permeability caused by adsorption and desorption of gases from the matrix blocks. The model equations can be used to calculate permeability changes caused by the production of methane from coal as well as the injection of gases, such as carbon dioxide, for sequestration in coal. Sensitivity analysis of the model found that each of the input variables can have a significant impact on the outcome of the permeability forecast as a function of changing pore pressure; thus, accurate input data are essential. The permeability model can also be used as a ...

2006-10-01

320

Transmutation of technetium in the Petten HFR. A comparison of measurements and calculations  

Energy Technology Data Exchange (ETDEWEB)

Within the framework of the EFTTRA cooperation between CEA, ECN, EDF, FZK, IAM and ITU, six metallic {sup 99}Tc rods have been irradiated in the Petten HFR for 193 effective full power days. During this irradiation, more than 6% of the {sup 99}Tc has been transmuted to the stable {sup 100}Ru. At ECN, one of the six rods has been examined in the hot cell laboratory. The ruthenium concentration in the rod measured by Isotope Dilution Mass Spectrometry reaches 6.4% at 5 mm from the bottom of the rod and 6.0% at 5 mm from the top. Also the axial and radial distributions of the ruthenium have been measured by Electron Probe Micro Analysis. The ruthenium concentrations calculated by the three-dimensional Monte Carlo code KENO reach 6.1% at 5 mm from the bottom of the rod and 5.7% at 5 mm from the top. These values are in reasonable agreement with the measured ones. However, the calculated radial distribution ...

1996-10-01

321

Procedure for obtaining visas for Switzerland and France - Signature rights  

CERN Multimedia

In accordance with the Status Agreements with CERN, Switzerland and France facilitate the entry of members of the Organization’s personnel onto their territories. Where relevant, detailed procedures for obtaining visas apply. Within the framework of those procedures, only the following individuals are authorised to initiate the Note verbale procedure as well as to sign the Official Invitation Letters and the Protocoles d’accueil. Kirsti ASPOLA (PH – CMO) Oliver BRÜNING (BE – ABP) Michelle CONNOR (PH – AGS) Sylvie DETHURENS FAVEZ (HR – SPS) David FOSTER (IT – DI) Nathalie GRUB (PH – AGS) Tadeusz KURTYKA (DG – PRJ) Jean-Pol MATHEYS (BE – ASR) Cécile NOELS (DG – PRJ) Connie POTTER (PH – AGS) Maria QUINTAS (HR – ...

2010-01-01

322

Effect of fulvic and humic acids and inorganic phase of soil on the sorption and extractability of /sup 239/Pu(IV)  

Science.gov (United States)

The effect of organic (fulvic and humic acids) and inorganic fractions of soil on the sorption and extractability of /sup 239/Pu(IV) as a function of pH was determined by using an equilibrium batch technique. The results indicated that Pu(IV) is strongly sorbed on the inorganic fraction of the soil under soil pH conditions normally encountered in natural environments. Plutonium appeared to form stable complexes or chelates with fulvic and humic acids in the pH range studied (1.3 to 11.7). In mixtures of pure fulvic or humic acids with soil inorganic fractions, extractability of Pu was substantially influenced by organic-inorganic interaction. The influence of the inorganic fractions was most evident in the lower pH ranges, whereas that of the organic materials was most evident in the higher pH ranges, generally above pH 6. Some implications of the results on ...

1979-11-01

323

The influence of amino acids on the biomineralization of hydroxyapatite in gelatin.  

Science.gov (United States)

The effects of pH on the calcium phosphate phase, of Tris and of amino acids, such as aspartic acid, glutamic acid, and serine on hydroxyapatite formation and morphology, were studied in double diffusion experiments. In this system, hydroxyapatite was only formed when the pH was around 7.4 or higher for the duration of the reaction. A decrease in pH resulted in the transformation of hydroxyapatite to octacalcium phosphate. Amino acids and Tris or the buffering capacity of Tris have an effect on the morphology of the synthetic hydroxyapatite. The presence of the additive results in spheres consisting of needles, blades or plates depending on the reaction system. PMID:12175941

2002-08-30

324

Effect of D-amino acids at Asp"2"3 and Ser"2"6 residues on the conformational preference of A#beta#_2_0_-_2_9 peptides  

International Nuclear Information System (INIS)

The effects of D-amino acids at Asp"2"3 and Ser"2"6 residues on the conformational preference of #beta#-amyloid (A#beta#) peptide fragment (A#beta#_2_0_-_2_9) have been studied using different spectroscopic techniques, namely vibrational circular dichroism (VCD), vibrational absorption, and electronic circular dichroism. To study the structure of the A#beta#_2_0_-_2_9, [D-Asp"2"3]A#beta#_2_0_-_2_9, and [D-Ser"2"6]A#beta#_2_0_-_2_9 peptides under different conditions, the spectra were measured in 10 mM acetate buffer (pH 3) and in 2,2,2-trifluoroethanol (TFE). The spectroscopic results indicated that at pH 3, A#beta#_2_0_-_2_9 peptide takes random coil with #beta#-turn structure, while [D-Ser"2"6]A#beta#_2_0_-_2_9 peptide adopts significant amount of polyproline II (PPII) type structure along with #beta#-turn contribution and D-Asp-substituted peptide ([D-Asp"2"3]A#beta#_2_0_-_2_9) adopts predominantly PPII type structure. ...

2005-09-30

325

Environmental trace gas analysis by proton-transfer-reaction mass spectrometry (PTR-MS)  

International Nuclear Information System (INIS)

The work presented here demonstrates the ability of proton-transfer-reaction mass spectrometry (PTR-MS) to perform fast-response measurements of volatile organic compounds (VOCs) (including methanol, acetonitrile, acetaldehyde, acetone, PAN-type compounds, alpha- and beta-pinene, nopinone and pinonaldehyde) at the pptv level and its versatile applicability in the field of environmental trace gas analysis. Laboratory and field experiments including various calibration techniques and intercomparisons with other measurement techniques such as gas chromatography, atmospheric pressure chemical ionization and Fourier transformation infrared spectroscopy were performed providing a first characterization of the PTR-MS instrument performance (sensitivity, detection limit, precision, accuracy). Typically a detection limit (S/N=2) of 50 pptv for a 10 s signal integration time, a precision of 5 % and an accuracy in the range between 10 ...

326

The Importance of Health Physics and Medical Integration in ...  

Science.gov (United States)

Richard E. Toohey, PhD, CHP. " Dose Coefficients for Intakes of Radionuclides via Contaminated Wounds; Application of the. NCRP Wound Model ...

327

Selenium and iodine labeled pH shift brain imaging agents  

International Nuclear Information System (INIS)

(Jan - Feb 1981). United Kingdom Kung, HF Tramposch, K. Blau, M. Buffalo

328

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

329

NPS Fees Report Part 1&2combined,db  

Science.gov (United States)

... A., M.A. David Ostergren, Ph.D. Northern Arizona University June 2003 NPS SOCIALSOCIAL RESEARCH LA...

330

Levels in "9"7Tc, "9"9Tc, "1"0"1Tc and "1"0"1Ru  

International Nuclear Information System (INIS)

... Thesis (Ph.D.). coincidence spectrometry excited states gamma spectra internal

331

Influence of pH, temperature and thermal treatment on site corrosion of SAE 304 steel in chlorinated solutions  

International Nuclear Information System (INIS)

The electrochemical behaviour and fracture morphology of homogenized and sensitized type SAE 304 stainless steel U bent specimens, in 3% NaCl solution, at pH=2.0 and pH=7.0 both at room temperature and 100"0C was studied. Polarization curves, galvanostatic and potentiostatic experiments were run. It could be observed that high temperature and low pH favour transgranular cracking and longer sensitization times lower fracture time and tend to give rise to intergranular fracture. Light sensitization can produce transgranular cracking even at room temperature, when the homogenized alloy does not present stress-corrosion cracking for the same condition. (Author).

332

Gene expression analysis identifies potential biomarkers of phenanthrene in human hepatocytes (HepG2)  

British Library Electronic Table of Contents (United Kingdom)

Polycyclic aromatic hydrocarbons (PAHs) are ubiquious in the environment both as natural products and as environmental contaminants. Among PAHs, phenanthrene (PH) that is ubiquitously distributed throughout the environment was subjected in this study. Although environmental distribution and metabolism of PH have been well reported, there are only a few studies examined the expression of mRNA and their functions on PH-induced toxicity. A new paradigm in toxicity screening, toxicogenomic technology represents a useful approach for evaluating the toxic properties of environmental pollutants. In this respect, we elicited the genes which were changed more than 2-fold by analysis of gene expression profiles in human hepatocellular carcinoma (HepG2) cells, exposed to PH by using human oligonucleo...

2011-01-01

333

Effect of headgroup dissociation on the structure of Langmuir monolayers  

Energy Technology Data Exchange (ETDEWEB)

The authors present results of grazing incidence X-ray diffraction studies concerning the effect of pH (and thus, of headgroup dissociation) on Langmuir monolayers of fatty acids, in the absence of any divalent cations in the aqueous subphase. An increase in pH transforms the distorted-hexagonal S phase first to the partially disordered Rotator-I phase with less distortion, and then to the completely disordered Rotator-II phase with an undistorted hexagonal structure. The S-Rotator-I and Rotator-I-Rotator-II transitions are pushed to lower temperatures with increase in pH. The fact that the effects of pH increase are almost identical to the effects of increasing temperature indicates the important role of headgroup-headgroup interactions in these monolayer phases.

2000-02-08

334

Correlation between proton pumping and the bacteriorhodopsin photocycle  

Energy Technology Data Exchange (ETDEWEB)

In an attempt to establish a relationship between proton pumping and the photocycle intermediates of bacteriorhodopsin, we have studied the effects of pH and temperature of flash-induced proton pumping and the photointermediates O/sub 640/ and M/sub 412/. The relative quantum yield of flash-induced proton pumping is both pH and temperature dependent. It is high in the acid pH range and at low temperatures but decreases in the basic pH range and at high temperatures. The decay of M/sub 412/ is biphasic. The amplitude of the slowly decaying component (M/sup s/) was found to be pH dependent with a pK similar to that of the ..delta..pH. The pH dependence of the fast-decaying component (M/sup f/) is opposite to that of M/sup s/ and ..delta..pH. Like that of M/sup s/, the amplitude of O/sub 640/ is high in the acid pH range, but unlike the ...

1984-11-01

335

Chromatography of metal ions with a triazine chelating resin  

International Nuclear Information System (INIS)

The synthesis, characterization, and some analytical applications of a new triazine resin are described. Separation of group IB, IIB, VIB, and VIIB metal ions from group VIII metal ions is achieved by this PDT-4 resin. Calcium(II) and magnesium(II) are taken up at pH = 6, 0.1 M acetate and are eluted at pH = 6, 0.1 M sodium nitrate. Copper(II) is retained at pH = 6, 0.1 M acetate and pH = 1 hydrochloric acid and is eluted subsequently by 5 M perchloric acid. Molybdenum(VI) is sorbed selectively from 0.1 N sulfuric acid or hydrochloric acid and is eluted in a tight band by 0.1 N sodium hydroxide. Numerous rapid column chromatographic separations are reported using this new resin, including analysis of NBS standard samples.

336

Asynchronous Digital Regulators  

Science.gov (United States)

... (tb*it 06(M WfIio[td) Page 2. Asynchronous Digital Regulators Vernon Scott Ritchey, Ph.D. ... Page 3. ASYNCHRONOUS DIGITAL REGULATORS ...

2011-05-13

338

X-Ray Fluorescence in Research on the Cultural Heritage  

Energy Technology Data Exchange (ETDEWEB)

Radionuclide X-ray fluorescence analysis is a method, which has many advantages for analysing various historic artefacts, as it is relatively cheap, sensitive and non-destructive, and it allows measurements in-situ. However, this analysis has also certain limitations especially concerning sensitivity to chemical elements only, irrespective of the compounds or chemical forms in which these elements have been bonded. In addition, light elements emitting very soft X-rays cannot be measured, and in order to detect a wide range of elements, it is necessary to carry out repeated measurements with different radiation sources. Despite these limitations, valuable information can be obtained about the composition of historic materials and data about the origin and age of these artefacts can be derived. Analyses of wall paintings, ancient metal sculptures or other objects of art provide the basis for historic considerations documented ...

2001-09-15

339

X-Ray Fluorescence in Research on the Cultural Heritage  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis is a method, which has many advantages for analysing various historic artefacts, as it is relatively cheap, sensitive and non-destructive, and it allows measurements in-situ. However, this analysis has also certain limitations especially concerning sensitivity to chemical elements only, irrespective of the compounds or chemical forms in which these elements have been bonded. In addition, light elements emitting very soft X-rays cannot be measured, and in order to detect a wide range of elements, it is necessary to carry out repeated measurements with different radiation sources. Despite these limitations, valuable information can be obtained about the composition of historic materials and data about the origin and age of these artefacts can be derived. Analyses of wall paintings, ancient metal sculptures or other objects of art provide the basis for historic considerations documented ...

2001-09-01

340

Wireline well logging an underutilized technique in reservoir evaluation  

Energy Technology Data Exchange (ETDEWEB)

Wireline well logs have three general uses in geothermal exploration and reservoir evaluation: reservoir parameter analysis, lithologic column determination, and reservoir size resolution. Reservoir flow testing data are acquired to understand the flow rate, life, and production potential of the geothermal reservoir. These data are a coarse subsurface measurement of the geothermal prospect. Wireline logs acquired from wells in a geothermal prospect are used to define in detail, or estimate the reservoir parameters of temperature, thickness, lateral size, amount of fracture and intergranular pore space, and the quantity and quality of fluid that might be produced. Laboratory measurements can be made on core samples and drill cuttings samples to define the intrinsic behavior of the materials and fluid that compose the geotheraml reservoir. Wireline log measurements are needed to correlate and link the ...

1981-01-01

341

Thermal infrared spectra of surface rocks. Comparison of in the laboratory, in situ, and remote sensing data; Chihyo ganseki no netsusekigaiiki bunko tokusei. Chijo sokutei data to remote sensing data no hikaku  

Energy Technology Data Exchange (ETDEWEB)

An ASTER (advanced spaceborne thermal emission and reflection radiometer) is one of the image sensors. It is to be installed in an earth survey polar orbit platform satellite, EOS-AM1, which is to be launched in 1998, and it is going to start its operation. Data observed by the thermal infrared remote sensing of ASTER include the spectral emissivity, and the spectral emission reflectivity which is expressed by the function of temperature. It is required to overcome technical problems how to extract the spectral emissivity from the observed data. The spectral emissivity extracted from the remote sensing data by the MMD method, measured for samples collected in Cuprite area, Nevada, and/or measured at sampled points were compared to each other and discussed. The hemisphere spectral reflectivity, which is indirect spectral emissivity, agreed well with the direct spectral emissivity. Data suggesting the establishment of Kirchhoff`s law were ...

1996-10-01

342

Testing of Critical Features of Polysilicon MEMS  

Energy Technology Data Exchange (ETDEWEB)

The behavior of MEMS devices is limited by the strength of critical features such as thin ligaments, oxide cuts joining layers, pin joints and hinges. Devices fabricated at Sandia's Microelectronic Development Laboratory have been successfully tested to investigate these features. A series of measurements were performed on samples with gage lengths of 15 to 1000 microns, using conventional and tungsten coated samples as well as samples that include the critical features of standard components in the test section. Specimens have a freely moving pin joint on one end that anchors the sample to the silicon die to allow rotation to reduce effects of bending. Each sample is loaded in uniaxial tension by pulling laterally with a flat tipped diamond in a computer-controlled Nanoindenter. Load is calculated by resolving the measured lateral and normal forces into the applied tensile force and frictional losses. The specimen ...

1999-12-02

343

Radionuclide release rates from spent fuel for performance assessment modeling  

Energy Technology Data Exchange (ETDEWEB)

In a scenario of aqueous transport from a high-level radioactive waste repository, the concentration of radionuclides in water in contact with the waste constitutes the source term for transport models, and as such represents a fundamental component of all performance assessment models. Many laboratory experiments have been done to characterize release rates and understand processes influencing radionuclide release rates from irradiated nuclear fuel. Natural analogues of these waste forms have been studied to obtain information regarding the long-term stability of potential waste forms in complex natural systems. This information from diverse sources must be brought together to develop and defend methods used to define source terms for performance assessment models. In this manuscript examples of measures of radionuclide release rates from spent nuclear fuel or analogues of nuclear fuel are presented. Each example represents a very different ...

1994-11-01

344

PIXE-PIGE analysis of some Indian medicinal plants  

Energy Technology Data Exchange (ETDEWEB)

The quantitative estimation of various trace element concentrations in medicinal plants is necessary for determining their effectiveness in treating various diseases and for understanding their pharmacological action. Elemental concentrations of some selected medicinal plants of north east India was measured by proton induced X-ray emission (PIXE) and proton induced {gamma}-ray emission (PIGE) techniques. PIXE measurements were carried out using 2.4 MeV collimated protons from the 3 MV tandetron accelerator of NCCCM, Hyderabad (India) while the PIGE measurements were carried out using 3 MeV protons from the same accelerator in the same laboratory. Accuracy and precision of the techniques were assured by analyzing certified reference materials in the same experimental conditions. Various elements of biological importance in man's metabolism were found to be present in varying concentrations in ...

2010-06-15

345

Neutron scattering and models: iron  

Energy Technology Data Exchange (ETDEWEB)

Differential elastic and inelastic neutron-scattering cross sections of elemental iron are measured from 4.5 to 10 MeV in increments of {approx}0.5 MeV. The measurements are made at >or{approx}40 scattering angles distributed between {approx}17 and 160 , with emphasis on elastic scattering and inelastic scattering due to the excitation of the yrast 2{sup +} state. The measured data is combined with earlier lower-energy results from this laboratory, with recent high-precision {approx}9.5-15 MeV results from the Physikalisch. Technische Bundesanstalt and with selected values from the literature to provide a detailed neutron-scattering data base extending from {approx}1.5 to 26 MeV. This data is interpreted in the context of spherical-optical and coupled-channels (vibrational and rotational) models, and the physical implications are discussed. Deformation, coupling, asymmetry and dispersive effects are ...

1996-08-12

346

Measurement of the parity violating asymmetry A{sub {gamma}} in n{yields}+p{yields}d+{gamma}  

Energy Technology Data Exchange (ETDEWEB)

The weak interaction between neutrons and protons has never been resolved experimentally. In analogy with the strong NN interaction, the weak NN interaction at low energy can be parametrized in terms of a meson exchange model with parity violating meson-nucleon couplings. Unlike the measured proton-proton weak interaction, the neutron-proton weak interaction is sensitive to the weak pion-nucleon coupling constant H{sub {pi}}{sup 1}. This coupling, which is responsible for the longest-ranged part of the weak NN interaction and is therefore an essential part of any description of weak interactions in nuclei, remains undetermined despite many years of effort. A measurement of the gamma ray directional asymmetry A{sub {gamma}} in the capture of polarized neutrons by parahydrogen has been proposed at Los Alamos National Laboratory. The goal of this experiment is to determine A{sub {gamma}} with a relative standard uncertainty of ...

2000-02-11

347

MONITORING POWER PLANT EFFICIENCY USING THE MICROWAVE-EXCITED PHOTOACOUSTIC EFFECT TO MEASURE UNBURNED CARBON  

Energy Technology Data Exchange (ETDEWEB)

Three test instruments are being evaluated to determine the feasibility of using photoacoustic technology for measuring unburned carbon in fly ash. The first test instrument is a single microwave frequency system previously constructed to measure photoacoustic signals in an off-line configuration. A second off-line instrument was constructed based in part on lessons learned with the first instrument, but which also expands the capabilities of the first instrument. Improvements include a control loop to allow more constant microwave power output and an ability to operate over a range of microwave frequencies. The third instrument, the on-line version of the fly ash monitor, has been designed, constructed, and initial efficiency tests have been conducted on the monitor's electrical components. This quarter focused on improving the signal strength of the accelerometer by increasing the power level of the microwaves that induced the ...

2004-07-01

348

Laboratory Evaluation of an Electrochemical Noise System for Detection of Localized and General Corrosion of Natural Gas Transmission Pipelines  

Energy Technology Data Exchange (ETDEWEB)

Gas transmission pipelines are susceptible to both internal (gas side) and external (soil side) corrosion attack. Internal corrosion is caused by the presence of salt laden moisture, CO{sub 2}, H{sub 2}S, and perhaps O{sub 2} in the natural gas. Internal corrosion usually manifests itself as general corrosion. However, the presence of chlorides in entrained water also can lead to pitting corrosion damage. The electrochemical noise technique can differentiate general from localized corrosion and provide estimates of corrosion rates without external perturbation of the corroding system. It is increasingly being applied to field and industrial installations for in situ corrosion monitoring. It has been used here to determine its suitability for monitoring internal and external corrosion damage on gas transmission pipelines. Corrosion measurements were made in three types of environments: (1) aqueous solutions typical of those found within gas pipelines in equilibrium ...

2003-03-16

349

Characterization system for Germanium detectors dedicated to gamma spectroscopy applied to nuclear waste  

International Nuclear Information System (INIS)

CEA-Valduc produces some radioactive waste (mainly alpha emitters). Legislation requires producers to sort their waste by activity and type of isotopes, and to package them in order to forward them to the appropriate reprocessing or storage facility. Our lab LMDE (laboratory for measurements on nuclear wastes and valuation) is in charge of the characterization of the majority of waste produced by CEA-Valduc. Among non-destructive methods to characterize a radioactive object, gamma-spectroscopy is one of the most efficient. We present to this conference the method we use to characterize nuclear waste and the system we developed to characterize our germanium detectors. The goal of this system is to obtain reliable numerical models of our detectors and calculate their efficiency curves. Measurements are necessary to checks models and improve them. These measurements are made on a bench using pinpoint ...

2009-06-07

350

Beam Test of a Prototype Detector Array for the PoGO Astronomical Hard X-Ray/Soft Gamma-Ray Polarimeter  

CERN Document Server

Polarization measurements in the X-ray and gamma-ray energy range can provide crucial information on massive compact objects such as black holes and neutron stars. The Polarized Gamma-ray Observer (PoGO) is a new balloon-borne instrument designed to measure polarization from astrophysical objects in the 30-100 keV range, under development by an international collaboration with members from United States, Japan, Sweden and France. To examine PoGO's capability, a beam test of a simplified prototype detector array was conducted at the Argonne National Laboratory Advanced Photon Source. The detector array consisted of seven plastic scintillators, and was irradiated by polarized photon beams at 60, 73, and 83 keV. The data showed a clear polarization signal, with a measured modulation factor of $0.42 \\pm 0.01$. This was successfully reproduced at the 10% level by the computer simulation package Geant4 after ...

2005-01-01

351

Absolute differential cross sections for the scattering of kilo-electron-volt O atoms  

International Nuclear Information System (INIS)

This paper reports measurements of absolute differential cross sections for the direct scattering of oxygen atoms by He, Ne, Ar, Kr, Xe, H_2, N_2, O_2, CO, CO_2, H_2O, SO_2, NH_3, CH_4, CF_4, and SF_6 targets. The measured cross sections include contributions from all elastic and inelastic processes that result in a fast neutral oxygen atom product. Cross sections are presented for 0.5- and 1.5-keV projectile energies over the laboratory angular range 0.2 degree endash 5 degree. When compared in the center-of-mass reference frame, these cross sections exhibit a high degree of similarity in both amplitude and angular dependence. The cross sections for N_2, CO, CO_2, and H_2O are inverted using a partial-wave analysis to yield empirical interaction potentials, which can then be used to extrapolate the measurements down to lower energies. Using these potentials, cross sections are evaluated at 0.1 keV. ...

352

Subcritical Noise Analysis Measurements with Fresh and Spent Research Reactor Fuels Elements  

Energy Technology Data Exchange (ETDEWEB)

The verification of the subcriticality is of utmost importance for the safe transportation and storage of nuclear reactor fuels. Transportation containers and storage facilities are designed such that nuclear fuels remain in a subcritical state. Such designs often involve excess conservatism because of the lack of relevant experimental data to verify the accuracy of Monte Carlo codes used in nuclear criticality safety analyses. A joint experimental research program between Oak Ridge National Laboratory, Westinghouse Safety Management Solutions, Inc., and the University of Missouri was initiated to obtain measured quantities that could be directly related to the subcriticality of simple arrays of Missouri University Research Reactor (MURR) fuel elements. A series of measurement were performed to assess the reactivity of materials such as BORAL, stainless steel, aluminum, and lead that are typically used in the construction ...

1999-02-01

353

Radon in soil gas survey in Curitiba (Brazil)  

International Nuclear Information System (INIS)

This work describes the radon in soil gas measurements performed during the last two years in cooperation between the Laboratory of Applied Nuclear Physics of the Federal University of Technology (UTFPR), the Nuclear Technology Development Center (CDTN) and the Institute of Radiation Protection and Dosimetry (IRD) from the Brazilian Nuclear Energy Commission (CNEN). Following previously concluded measurements of radon concentration in dwellings and the measurements of 222Rn activity in drinking water collected at artesian bores of Curitiba urban area, present step of activities has been dedicated to measurements of radon concentration in soil gas. Experimental setup was based on the Professional Radon Monitor (ALPHA GUARD) connected to specially developed for such measurements Soil Gas Probe through the air pump and filter system. After the Probe was inserted, ...

2002-10-08

354

Prompt fission neutron energy spectra induced by fast neutrons  

International Nuclear Information System (INIS)

Prompt fission neutron energy spectra for "2"3"5U and "2"3"9Pu have been measured for fission neutron energies greater than the energy of the incident neutrons inducing fission. The measurements were undertaken to investigate the shape dependence of the fission neutron spectra upon both the incident neutron energy and the mass of the nucleus undergoing fission. Measurements were made for both nuclides at incident neutron energies of 0.50, 1.50, 2.50 and 3.50 MeV. The data are presented either as relative yields or as ratios of measured spectra to that of "2"3"5U at 0.50 MeV. Incident neutrons were produced by the "7Li(p,n)"7Be reaction using a pulsed, bunched proton beam from the 5.5 MV Van de Graaff accelerator at the University of Massachusetts Lowell Radiation Laboratory. Fission neutrons were detected by a thin liquid scintillator with good time resolution capabilities. Neutron ...

355

Partitioning Tracers for In-Situ Measurement of Nonaqueous Phase Liquids in the Subsurface - Final Report - 09/15/1996 - 09/14/2000  

Energy Technology Data Exchange (ETDEWEB)

The overall goal of the proposed project is to explore the use of partitioning tracers to characterize dense nonaqueous phase liquids (DNAPLs) in aquifer systems. Bulk-phase partitioning tracers will be investigated to detect and determine DNAPL saturation, while interface partitioning tracers will be investigated to measure the area of the DNAPL-water interface. The specific objectives that will be addressed to accomplish this goal are: (1) Investigate the use of partitioning tracers to detect and determine both the saturation and interfacial area of DNAPLs in saturated porous media. (2) Investigate the effect of rate-limited mass transfer on the transport behavior of partitioning tracers. (3) Investigate the effect of porous-media heterogeneity on the transport behavior of partitioning tracers. (4) Develop and evaluate mathematical models capable of simulating the transport of partitioning tracers in complex systems. This proposal outlines an integrated approach ...

2000-09-14

356

Electrochemical noise measurements of sustained microbially influenced pitting corrosion in a laboratory flow loop system.  

Energy Technology Data Exchange (ETDEWEB)

Because of the chaotic nature of the corrosion process and the complexity of the electrochemical noise signals that are generated, there is no generally accepted method of measuring and interpreting these signals that allows the consistent detection and identification of sustained localized pitting (SLP) as compared to general corrosion. We have reexamined electrochemical noise analysis (ENA) of localized corrosion using different hardware, signal collection, and signal processing designs than those used in conventional ENA techniques. The new data acquisition system was designed to identify and monitor the progress of SLP by analyzing the power spectral density (PSD) of the trend of the corrosion current noise level (CNL) and potential noise level (PNL). Each CNL and PNL data point was calculated from the root-mean- square value of the ac components of current and potential fluctuation signals, which were measured simultaneously during a short ...

1999-01-13

357

Dosimetry measurements of x-ray and neutron radiation levels near the shuttle and end beam dump at the advanced test accelerator: Beam Research Program  

International Nuclear Information System (INIS)

Electron beams as a source of directed energy are under study at the Lawrence Livermore National Laboratory (LLNL). An intense 10-kA, 50-MeV, 50-ns full-width half-maximum, pulsed electron beam is generated by the prototype Advanced Test Accelerator (ATA) at the Laboratory's Site 300. Whenever the electron beam is stopped in materials, intense radiation is generated. Estimates based on available data in the literature show that for materials such as lead, photon radiation (x ray, gamma, bremsstrahlung) levels can be as large as 10"4 roentgens per pulse at 1 m in the zero-degree direction (i.e., the electron-beam direction). Neutrons, which are emitted isotropically, are produced at a level of 10"1"3 n/m"2 per pulse. Depending upon the number of pulses and the shielding geometry, the accumulated dose is potentially lethal to personnel and potentially damaging to instrumentation that may be used for diagnostics. To provide shielding for ...

358

Corrosion probes for fireside monitoring in coal-fired boilers  

Energy Technology Data Exchange (ETDEWEB)

Corrosion probes are being developed and combined with an existing measurement technology to provide a tool for assessing the extent of corrosion of metallic materials on the fireside in coal-fired boilers. The successful development of this technology will provide power plant operators the ability to (1) accurately monitor metal loss in critical regions of the boiler, such as waterwalls, superheaters, and reheaters; and (2) use corrosion rates as process variables. In the former, corrosion data could be used to schedule maintenance periods and in the later, processes can be altered to decrease corrosion rates. The research approach involves laboratory research in simulated environments that will lead to field tests of corrosion probes in coal-fired boilers. Laboratory research has already shown that electrochemically-measured corrosion rates for ash-covered metals are similar to actual mass loss ...

2005-01-01

359

X-ray fluorescence in research on Czech cultural monuments  

Energy Technology Data Exchange (ETDEWEB)

Radionuclide X-ray fluorescence analysis (RXRFA), as a non-destructive method, relatively simple and allowing measurements to be carried out in situ, is an excellent tool in research on various objects of art. A range of artefacts have been investigated by our laboratory, in part for the purposes of history of art and in part as a basis for restoration works - medieval frescoes in some Czech castles and churches, metal sculptures and objects of applied art, paints and inks of old manuscripts, paintings. Some of these are among the most valuable monuments in the Czech cultural heritage. The contribution of the results of the tests to the investigation of their 'life story' and, in some cases, to their conservation, is not negligible. Later additions and repairs can be recognised, and materials and technologies that are close to their historic counterparts can be used in restoration work.

2004-01-01

360

X-ray fluorescence in research on Czech cultural monuments  

International Nuclear Information System (INIS)

Radionuclide X-ray fluorescence analysis (RXRFA), as a non-destructive method, relatively simple and allowing measurements to be carried out in situ, is an excellent tool in research on various objects of art. A range of artefacts have been investigated by our laboratory, in part for the purposes of history of art and in part as a basis for restoration works - medieval frescoes in some Czech castles and churches, metal sculptures and objects of applied art, paints and inks of old manuscripts, paintings. Some of these are among the most valuable monuments in the Czech cultural heritage. The contribution of the results of the tests to the investigation of their 'life story' and, in some cases, to their conservation, is not negligible. Later additions and repairs can be recognised, and materials and technologies that are close to their historic counterparts can be used in restoration work.

2004-01-01

361

Use of a novel acoustic dissolved oxygen transmitter for fish telemetry  

DEFF Research Database (Denmark)

The multiple responses of fishes to changes in dissolved oxygen saturations have been studied widely in the laboratory. In contrast only few studies have included field observations. The objective of the present study was to evaluate the performance of a novel acoustic dissolved oxygen transmitter for field biotelemetry. The results demonstrated that the output of the transmitter was unaffected by three different temperatures (10 to 30 degrees C) and described the dissolved oxygen saturation with high accuracy (r(2) > 0.99) over the entire range of 0 to 191% saturation. The response time (>= 90% of end value) of the transmitter was 12 s both in terms of decreasing (100 to 0%) and increasing (0 to 100%) oxygen saturations. When externally attached to fishes the present findings support the use of the transmitter for reliable dissolved oxygen measurements on individuals living in environments that may change both temporally and spatially ...

2006-01-01

362

Uranium Mass and Isotopic Analysis. A new drum tomographic gamma scanning system  

Energy Technology Data Exchange (ETDEWEB)

The NIS-6 group at Los Alamos National Laboratory pioneered the development of Tomographic Gamma Scanning and continue to improve its utility in real measurement situations. Building on this experience we report the development of a state of the art TGS system suitable for industrial applications. The image reconstruction and visualization software has been integrated into the familiar Canberra NDA2000 software suite which also handles all other aspects of the data acquisition and management. In this paper we describe the salient design and performance parameters of the system. The application of gamma-ray tomography to safeguards for improved assay accuracy and knowledge confirmation is discussed. In particular we compare and contrast the relative merits of this TGS and a traditional Segmented Gamma Scanner and illustrate how the 3-D visualization of the TGS image can provide valuable additional information.

2003-05-01

363

Three-dimensional elastic lidar winds  

Energy Technology Data Exchange (ETDEWEB)

Maximum cross-correlation techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum cross-correlation technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a function of range and altitude from incoherent elastic backscatter lidar data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three- dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain following winds in the Rio Grande valley.

1996-07-01

364

Survival of gas phase amino acids and nucleobases in space radiation conditions  

CERN Document Server

We present experimental studies on the photoionization and photodissociation processes (photodestruction) of gaseous amino acids and nucleobases in interstellar and interplanetary radiation conditions analogs. The measurements have been undertaken at the Brazilian Synchrotron Light Laboratory (LNLS), employing vacuum ultraviolet (VUV) and soft X-ray photons. The experimental set up basically consists of a time-of-flight mass spectrometer kept under high vacuum conditions. Mass spectra were obtained using photoelectron photoion coincidence technique. We have shown that the amino acids are effectively more destroyed (up to 70-80%) by the stellar radiation than the nucleobases, mainly in the VUV. Since polycyclic aromatic hydrocarbons have the same survival capability and seem to be ubiquitous in the ISM, it is not unreasonable to predict that nucleobases could survive in the interstellar medium and/or in comets, even as a stable cation.

2008-01-01

365

Surface analysis by Fourier-transform infrared (FTIR) spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

A diffuse-reflectance capability for the Fourier transform infrared spectrometer at the Y-12 Plant Laboratory has been implemented. A sample cell with a 25 to 400/sup 0/C temperature-controlled sample stage and an ultrahigh-vacuum-to-atmospheric pressure gas-handling capability has been developed. Absorbance of light from the spectrometer beam, resulting from the beam being scattered from a powder sample, can be measured. This capability of detecting molecular species on and in powders is to be used to study chemisorption on actinide and rare-earth metals, alloys, and compounds. Cell design is described along with experiments demonstrating its performance in detecting moisture absorption on uranium oxide, moisture and carbon dioxide absorption on the lithium hydride/hydroxide system, and carbon dioxide absorption on potassium borohydride. 13 figures.

1981-08-12

366

Structural aging program to assess the adequacy of critical concrete components in nuclear power plants  

International Nuclear Information System (INIS)

The Structural Aging (SAG) Program is carried out by the Oak Ridge National Laboratory (ORNL) under sponsorship of the United States Nuclear Regulatory Commission (USNRC). The Program has evolved from preliminary studies conducted to evaluate the long-term environmental challenges to light-water reactor safety-related concrete civil structures. An important conclusion of these studies was that a damage methodology, which can provide a quantitative measure of a concrete structure's durability with respect to potential future requirements, needs to be developed. Under the SAG Program, this issue is being addressed through: establishment of a structural materials information center, evaluation of structural component assessment and repair technologies, and development of a quantitative methodology for structural aging determinations. Progress to date of each of these activities is presented as well as future plans. 7 refs., 5 figs.

1989-08-14

367

Standardisation of "2"1"0Pb by Cerenkov counting  

International Nuclear Information System (INIS)

A standard of "2"1"0Pb in solution was produced at the National Physical Laboratory by a novel technique combining Cerenkov counting with the established liquid scintillation efficiency tracing technique known as the CIEMAT/NIST method. Coincidence counting was applied in order to validate the measurements and the activity concentrations of the solution determined with each technique are shown to be in agreement. Radiochemical separation of the "2"1"0Pb from its daughters was also necessary and the scheme for the separation is described. After performing this two-stage standardisation, the uncertainty was successfully lowered to 0.66% (k=1). This uncertainty is approximately a factor of four lower than previously achieved at NPL by the classical method of standardisation of radionuclides, i.e. coincidence counting.

2011-05-01

368

Some aspects of concentrated sulphuric acid storage tank corrosion  

Energy Technology Data Exchange (ETDEWEB)

Carbon steel is frequently used to construct concentrated sulphuric acid storage tanks. This paper discussed the corrosion performance of carbon steel tanks and outlined the underlying mechanisms responsible for major corrosion modes. Analyses of hydrogen grooving and dilute acid corrosion failure mechanisms were presented. Recent corrosion-induced leak failures were also discussed. The use of anodic protection and organic coatings as a corrosion control measure was also evaluated. The results of laboratory studies that were conducted to understand corrosion-induced failures showed that carbon steel electrodes exhibited transpassive corrosion at relatively high anodic potentials, while stainless steel electrodes exhibited transpassive corrosion at anodic potentials less than 1 V. It was concluded that corrosion-induced leaks can be prevented by using anodic protection and baked phenolic coating technologies. 23 refs., 9 figs.

2009-07-01

369

Radiation hazard control report  

Energy Technology Data Exchange (ETDEWEB)

The radiation control carried out in Atomic Energy Research Institute, Kinki University, for the reactor installation and the tracer/accelerator facilities from April, 1981, to March, 1982, is described. The reactor was operated for total 1057.1 hours at the maximum heat output of 1 W. The persons subject to radiation protection as of April, 1981, were 126 persons in all, including 23 in radiation work and 11 in X-ray work, etc. The contents of this report are as follows: personnel monitoring (health examination, the control of individual exposure dose); laboratory monitoring (the measurement of area dose rate, radioactive concentration in air and water, and surface contamination density); field monitoring (environmental ..gamma..-ray dose rate, radioactive concentration in environmental samples); the use of unsealed radioisotopes, etc.

1982-12-01

370

Quantitative measurements of injections into porous media with contrast based MRI  

British Library Electronic Table of Contents (United Kingdom)

Porous flow occurs in a wide range of materials and applies to many commercially relevant applications such as oil recovery, chemical reactors and contaminant transport in soils. Typically, breakthrough and pressure curves of column floods are used in the laboratory characterization of these materials. These characterization methods lack the detail to easily and unambiguously resolve flow mechanisms with similar effects at the core scale that can dominate at the aquifer or oil field scale, as well as the effects of geometry that control the flow at interfaces as in a perforated well or the inlet of an improperly designed column. Non-invasive imaging techniques such as MRI have been shown to provide a far more detailed characterization of the properties of the solid matrix and flow, but usu...

2011-01-01

371

Prospects for the direct detection of the cosmic neutrino background  

Energy Technology Data Exchange (ETDEWEB)

The existence of a cosmic neutrino background - the analogue of the cosmic microwave background - is a fundamental prediction of standard big bang cosmology. Up to now, the observational evidence for its existence is rather indirect and rests entirely on cosmological observations of, e.g., the light elemental abundances, the anisotropies in the cosmic microwave background, and the large scale distribution of matter. Here, we review more direct, weak interaction based detection techniques for the cosmic neutrino background in the present epoch and in our local neighbourhood. We show that, with current technology, all proposals are still off by some orders of magnitude in sensitivity to lead to a guaranteed detection of the relic neutrinos. The most promising laboratory search, based on neutrino capture on beta decaying nuclei, may be done in future experiments designed to measure the neutrino mass through decay kinematics. (orig.)

2009-01-15

372

Progress Report Towards the ICANOE Detector  

CERN Document Server

We present a proposal for a combined ICARUS & NOE general purpose detector, to be installed in Hall B of the Gran Sasso Laboratory.The main scientific goal is the one of elucidating in a comprehensive way the pattern of neutrino $9 masses and mixings, following both (1) the S-KAM results and (2) the predictions on atmospheric neutrinos of the large solution of the Solar Neutrinos deficit. To achieve these goals, the experimental method is based upon the $9 complementary and simultaneous detection of CERN beam (CNGS) and cosmic ray (CR) events. This is made possible because of the complete isotropy of the detection technique. For the currently allowed values of the S-KAM results, both $9 CNGS and cosmic ray data will give independent measurements and provide a precise $(sin^{2}2\\theta; \\Delta m^{2})$ determination rather than a wide band of allowed values. Since we can observe and unambiguously identify $9 $\

1999-01-01

373

Programmable radionuclide X-ray fluorescence multi-channel spectrometric analyzer, type 123-1  

International Nuclear Information System (INIS)

The whole equipment consists of three separate portable parts: a detector case, a microprocessor and a graphic TV monitor. Magnetic tape memory and an x-y recorder can be connected for recording the measured spectra. The analyzer contains two built-in exchangeable excitation radionuclides. Fluorescence and scattered radiation is detected using a proportional detector. The detected pulses are analyzed by a 256-channel analyzer and the results are shown on the display. The device may be used in mining laboratories, coal and ore dressing plant control rooms or in mining fields of open cast mines for quick detection of the quality of mined or dressed raw materials. (E.S.). 1 fig.

1988-01-01

374

Penile Rehabilitation after Radical Prostatectomy: Where Do We Stand and Where Are We Going?  

British Library Electronic Table of Contents (United Kingdom)

ABSTRACT Introduction. Postprostatectomy erectile dysfunction (ED) remains a serious quality-of-life issue. Recent advances in the understanding of the mechanism of postprostatectomy ED have stimulated great attention toward penile rehabilitation. Aim. This review presents and analyzes a contemporary series of the recent medical literature pertaining to penile rehabilitation therapy after radical prostatectomy (RP). Main Outcome Measures. The laboratory and clinical studies related to penile rehabilitation are analyzed. The validity of the methodology and the conclusion of the findings from each study are determined. Methods. The published and presented reports dealing with penile rehabilitation following RP in human and cavernous nerve injury in animal models are reviewed. Results. Exciti...

2007-01-01

375

PHOTON-HADRON INTERACTIONS AT RHIC AND LHC ENERGIES.  

Energy Technology Data Exchange (ETDEWEB)

Heavy Ion Collisions at RHIC and LHC energies are potentially an interesting laboratory for the study of QED. In these collisions, a Heavy Ion in one beam sees a highly Lorentz contracted electric field due to an oncoming beam particle. The Electric field reaches a maximum value of E {approx_equal} {gamma}{sub eff} {center_dot} Z {center_dot} e/b{sup 2}, where the apparent Lorentz factor, {gamma}{sub eff} = 2 {center_dot} {gamma}{sub beam}{sup 2} - 1. The collision may be viewed in terms of a flux of photons colliding with a stationary ion target using the equivalent photon approximation, originally introduced by Fermi in 1924. We show that the cross section for Inelastic Electromagnetic Interactions of Heavy Ions are both calculable and have been measured in the first RHIC running period.

2002-03-01

376

New Permeameters for In Situ Characterization of Unsaturated Heterogeneous Permeability: Development, Design, Testing, and Application  

Energy Technology Data Exchange (ETDEWEB)

The original objective of our EMSP research was to design, develop, and test new in situ field permeameters for use in spatial variability studies of unsaturated hydraulic properties. We initially focused on activities related to development and testing of techniques for inverting permeameter data, development of numerical tools for data inversion, error evaluation for permeameter design, and permeameter component design. However, the results of error evaluations for permeameter design caused us to redirect our research, and reformulate our research objectives. We discovered that small, simple measurement errors lead to significant bias in the estimated hydraulic properties and their spatial statistics. Our reformulated research objective became the evaluation of the origin, impact and relevance of spatial bias in field-and laboratory-estimated unsaturate hydraulic properties, with an emphasis on spatial statistics and the resulting predictions ...

2001-12-01

377

Modeling of lean premixed combustion in stationary gas turbines  

Energy Technology Data Exchange (ETDEWEB)

Lean premixed combustion (LPC) of natural gas is of considerable interest in land-based gas turbines for power generation. However, modeling such combustors and adequately addressing the concerns of LPC, which include emissions of nitrogen oxides, carbon monoxide and unburned hydrocarbons, remains a significant challenge. In this paper, characteristics of published simulations of gas turbine combustion are summarised and methods of modeling turbulent combustion are reviewed. The velocity-composition PDF method is selected for implementation in a new comprehensive model that uses an unstructured-grid flow solver. Reduced mechanisms for methane combustion are evaluated in a partially stirred reactor model. Comprehensive model predictions of swirl-stabilised LPC of natural gas are compared with detailed measurements obtained in a laboratory-scale combustor. The model is also applied to industrial combustor geometries. (Author)

1999-07-01

378

Idaho Explosives Detection System  

Energy Technology Data Exchange (ETDEWEB)

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

2005-12-01

379

Follow-up of pregnant women exposed to chicken pox: an audit of relationship between level of antibody and development of chicken pox  

British Library Electronic Table of Contents (United Kingdom)

The purpose of this study was to validate through natural exposure a cut-off level of varicella zoster IgG as protective against infection with varicella zoster virus (VZV). Laboratory testing to determine VZV immune status of pregnant women exposed to varicella is recommended. Quantitative assays are now available which are sensitive and specific. More than 200 consecutive requests for screening in pregnant patients with recent varicella contacts were followed-up by questionnaire. DiaSorin LIAISON and VZV time resolved fluorescence immuno assay (VZV TRFIA) were used to measure VZV antibody level. One hundred fifty out of 209 (72%) questionnaires were returned; 14 patients developed varicella, 129 did not and seven were not known. Patients who had been given VZIG and developed varicella on...

2011-01-01

380

FIRESET  

Science.gov (United States)

FIRESET is a PC-based computer code which calculates current as a function of time for an RLC circuit containing up to fifteen series conductors which undergo rapid heating and subsequent explosion as a consequence of an electric current which passes through them. In its original form, the code was developed to model electrical waveforms measured when a large, typically 25.4 x 25.4 x 0.051-mm, aluminum foil was exploded using a capacitor bank with tens of kilojoules of stored energy. The code proved to be useful for this purpose, and it was recognized that it could also be used for modeling the electrical response of detonator bridgewires. In view of the increasing use of slapper detonators for DOD applications, we wish to make the latest version of the code, available to DOD laboratories and contractors for use in designing firing systems which employ slapper or exploding bridgewire detonators. This document provides instructions for the code.

1988-02-19

381

Exclusive ?0 electroproduction on transversely polarized protons  

International Nuclear Information System (INIS)

The exclusive electroproduction of ?0 mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. Spin density matrix elements for this process were determined from the measured production- and decay-angle distributions of the produced ?0 mesons. These matrix elements embody information on helicity transfer and the validity of s-channel helicity conservation in the case of a transversely polarized target. From the spin density matrix elements, the leading-twist term in the single-spin asymmetry was calculated separately for longitudinally and transversely polarized ?0 mesons. Neglecting s-channel helicity changing matrix elements, results for the former can be compared to calculations based on generalized parton distributions, which are sensitive to the contribution of the total angular momentum of the quarks to the proton spin.

2009-08-17

382

Energy saving in existing buildings. Experiences with 'Therma' buildings. Energieeinsparung im Bestand. Erfahrungen mit den Therma-Bauten  

Energy Technology Data Exchange (ETDEWEB)

A number of buildings dating from the 1950s and 1960s were retrofitted with thermal insulation in order to cut energy consumption. This took place within the building competition 'Therma' nitrated by the Federal Ministry of Regional Planning, Building and Town Planning in 1974. Result at that time were so encouraging that now, 15 years later the results were checked again with special attention to the long-term performance of the thermal insulation measures. Laboratory tests prove that the building materials are still in good condition and that humidity has not increased with age. Cracks in the surface plaster of the compound insulation systems occurred at different frequencies and intensities and usually caused by thermal tensions. (BWI).

1992-04-01

383

Electronics Personal Dosemeter (EPD-N) Test and Evaluation Report  

Energy Technology Data Exchange (ETDEWEB)

Three electronic personal dosimeters (EPD-N) manufactured by Siemens, serial numbers 0635, 0658, and 0683, were tested at the Radiation Calibration Laboratory for an evaluation of their response to neutron, gamma and x-ray radiation. Designed to provide real-time neutron and photon dosimetry, the EPD-N is capable of estimating and displaying neutron and gamma dose components separately for a range of energies from 50 keV to 7 MeV for photon and 0.025 eV to > 10 MeV for neutron. All tests were conducted using the factory calibrations. A technical representative of the manufacturer indicated that site-specific calibrations are required as factory settings are calibrated for the lowest neutron energy limit of 0.025 eV. This raises concerns about the reliability of these devices in measuring neutrons when calibrations are made for a specific site radiological characterization then used at another site.

2003-04-08

384

Constraining Parity Violation in Gravity with Measurements of Neutron-Star Moments of Inertia  

CERN Document Server

Neutron stars are sensitive laboratories for testing general relativity, especially when considering deviations where velocities are relativistic and gravitational fields are strong. One such deviation is described by dynamical, Chern-Simons modified gravity, where the Einstein-Hilbert action is modified through the addition of the gravitational parity-violating Pontryagin density coupled to a field. This four-dimensional effective theory arises naturally both in perturbative and non-perturbative string theory, loop quantum gravity, and generic effective field theory expansions. We calculate here Chern-Simons modifications to the properties and gravitational fields of slowly spinning neutron stars. We find that the Chern-Simons correction affects only the gravitomagnetic sector of the metric to leading order, thus introducing modifications to the moment of inertia but not to the mass-radius relation. We show that an observational determination of the moment of ...

2009-01-01

385

Collisions between H"+ and H_2 at kilo-electron-volt energies: Absolute differential cross sections for small-angle direct, single-, and double-charge-transfer scattering  

International Nuclear Information System (INIS)

Measurements of absolute differential cross sections for H"+-H_2 direct, single-, and double-charge-transfer scattering at 0.5, 1.5, and 5.0 keV are reported at laboratory scattering angles less than 1 degree with an angular resolution of approximately 0.02 degree. The cross sections exhibit deep interference oscillations in single-charge-transfer scattering, but no such oscillations are present in direct and double-charge-transfer scattering. Theoretical cross sections derived using the diatoms-in-molecules method to describe the molecular states in a semiclassical molecular-orbital three-state close-coupling model within a semiclassical framework agree satisfactorily with the experimental results.

386

CO and CO2 emissions from spontaneous heating of coal under different ventilation rates  

British Library Electronic Table of Contents (United Kingdom)

Carbon monoxide (CO) and carbon dioxide (CO2) emissions during a spontaneous heating event in a coal mine are important gases to monitor for detecting the spontaneous heating at an early stage. However, in underground coal mines, the CO and CO2 concentrations and their related fire ratios may be affected by mine ventilation. In this study, CO and CO2 emissions from spontaneous heating of a U.S. coal sample were evaluated in an isothermal oven under different airflow ventilation rates ranging from 100 to 500cm^3/min. Laboratory experiments were conducted at oven temperatures of 70, 90, and 100^oC. The temperature at the center of the coal sample was continually monitored, while the CO, CO2, and oxygen (O2) concentrations of the exit gas were continually measured. The results indicate that C...

2011-01-01

387

CANDU 6 fuel behaviour in power ramp conditions  

International Nuclear Information System (INIS)

The facilities in the Institute for Nuclear Research at Pitesti allow the testing, handling and examination of nuclear fuel and irradiated materials. The most important facilities are the TRIGA Steady State Research and Material Test Reactor and the Post-Irradiation Examination Laboratory (PIEL). The purpose of this work is to determine by post-irradiation examination, the behavior of CANDU fuel, irradiated in 14 MW TRIGA reactor. The fuel was irradiated in power ramp conditions. The results of post-irradiation examination are: - Visual inspection and photography of the outer appearance of sheath; - Profilometry (diameter, bending, ovality) and length measuring; - Determination of axial and radial distribution of the fusion products activity by gamma scanning and tomography; - Microstructural characterization by metallographic and ceramographic analyzes; - Mechanical properties determination. The data obtained from the post-irradiation ...

2009-10-12

388

Basic mechanisms of radiation effects in the natural space radiation environment  

Energy Technology Data Exchange (ETDEWEB)

Four general topics are covered in respect to the natural space radiation environment: (1) particles trapped by the earth`s magnetic field, (2) cosmic rays, (3) radiation environment inside a spacecraft, (4) laboratory radiation sources. The interaction of radiation with materials is described by ionization effects and displacement effects. Total-dose effects on MOS devices is discussed with respect to: measurement techniques, electron-hole yield, hole transport, oxide traps, interface traps, border traps, device properties, case studies and special concerns for commercial devices. Other device types considered for total-dose effects are SOI devices and nitrided oxide devices. Lastly, single event phenomena are discussed with respect to charge collection mechanisms and hard errors. (GHH)

1994-06-01

389

Analysis of neutron emission spectra for 30-50 MeV #alpha#-particle induced reactions in thick targets  

International Nuclear Information System (INIS)

Comparisons of calculated neutron yield distributions from #alpha#-particle induced reactions on thick targets are made with measured data to analyze the initial reaction process in the framework of the exciton (hybrid) model code ALICE91 (M. Blann, Lawrence Livermore National Laboratory Report UCID 19614, 1982). We have considered two reaction mechanisms: dissolution of the #alpha# in the nuclear field, and preequilibrium processes initiated by #alpha#-nucleon collisions. Both these processes seem to contribute to the emitted neutron spectra in varying proportions depending on the incident #alpha# energy and possibly on the target nucleus. Contributions from other processes appear to be non-negligible.

2003-06-01

390

Absolute differential cross sections for electron capture and loss by kilo-electron-volt hydrogen atoms  

International Nuclear Information System (INIS)

This paper reports measurements of absolute differential cross sections for electron capture and loss for fast hydrogen atoms incident on H_2, N_2, O_2, Ar, and He. Cross sections have been determined in the 2.0- to 5.0-keV energy range over the laboratory angular range 0.02 degree--2 degree, with an angular resolution of 0.02 degree. The high angular resolution allows us to observe structure at small angles in some of the cross sections. Comparison of the present results with those of other authors generally shows very good agreement.

391

A beam funnelling demonstration: Experiment and simulation  

Energy Technology Data Exchange (ETDEWEB)

Accelerator concepts for heavy-ion fusion require small emittance, high-current beams. Such applications could include funnels in which high-current, like-charged particle beams are interlaced to double beam current while retaining small emittances. The first experimental demonstration confirming the beam dynamics of the funnel principle was recently completed at Los Alamos National Laboratory. A single-leg prototype 5-MeV, H{sup {minus}} funnel was successfully tested. This single-beam demonstration explored physics issues of a two-beam funnel. It contained elements for emittance control, position control, and rf deflection, as well as diagnostics for measurement of beam intensity, position and angle centroids, energy and phase centroids, and transverse and longitudinal phase-space distributions. Results of the experiment will be presented along with comparisons to simulations. 7 refs., 5 figs.

1990-01-01

392

A Model for Chlorine Dioxide Delignification of Chemical Pulp  

British Library Electronic Table of Contents (United Kingdom)

A phenomenon based model for chlorine dioxide delignification of chemical pulp is introduced. The pulp suspension environment is modeled using the concept of two liquid phases, one inside and the other external to the fiber wall. Physico-chemical processes taking place during delignification are implemented with thermodynamic, mass transfer and reaction kinetic models. A broad library of chemical reactions is introduced. Inclusion of each reaction is justified. The model response is tested against experimental laboratory delignification results (o-delignified birch pulp). The experimental data consists of kappa number, hexenuronic acid, inorganic oxy-chlorine compound, and organochlorine (AOX, OX) measurements at several time points during five delignification experiments. The model predic...

2010-01-01

393

Steam generator local water chemistry and SCC of austenitic steel  

Energy Technology Data Exchange (ETDEWEB)

The titanium stabilized austenitic steel similar to the type of 321 is sensitive to the stress corrosion crackingunder horizontal steam generator operating condition. SCC was observed under crevice corrosion parameters and has resulted in the transgranular or intergranular cracking at the both, components primary collectors and heat exchange tubes. The crevice environment is characterized by aggressive impurities and 'non aggressive' compounds. Sulfates and chlorides as aggressive species and silicates and alumino-silicates as 'non aggressive' species on the other hand are present in significant amount in the crevice environment under operating condition. Local water chemistry parameters were evaluated with MULTEQ Code. As input data the measured operational values of local and bulk environments have been used. The determined parameters were compared with the results of thread hole environment analyses and tube surface ...

1998-07-01

394

Passivation behavior of SUS 304 stainless steel in neutral solutions at elevated temperature  

Energy Technology Data Exchange (ETDEWEB)

Cyclic voltammograms of SUS 304 stainless steel in various neutral solutions such as Na/sub 2/SO/sub 4/ at high temperature were measured, as a successive study to previous report in which effects of temperature and pH on polarization behavior of stainless steel were studied. In this measurement Ag/AgCl reference electrode and platinum counter electrode were used in a static autoclave lined with inconel. Passive films formed in various conditions were analysed by electron diffraction and Auger spectroscopy. Results obtained were compared with anodic behavior of iron, chromium and nickel and with thermodynamical stabilities of their compounds. The main results are summarized as follows. (1) Stainless steel shows such electrochemical behavior as active dissolution, passivation and transpassivation in a deaerated neutral solution at 250/sup 0/C after fully reductive treatment of the specimen. In air-saturated solution, the ...

1981-03-01

395

NMR of a synthetic peptide spanning the triphosphate binding site of adenosine 5'-triphosphate in actin  

Energy Technology Data Exchange (ETDEWEB)

The amino acid residues 114-118 in actin were found to be implicated strongly in the binding of nucleotide, and as would be expected for such an important binding site, they are located in a completely conserved region of the actin sequence. A 19-residue peptide with the actin sequence 106-124 was synthesized in order to span the putative triphosphate binding site. Proton NMR spectra of the actin peptide 114-118 in the presence and absence of ATP indicated that Arg-116 and Lys-118 are particularly involved in binding ATP. A strong binding of ATP to the peptide 106-124 also was measured. Tripolyphosphate bound to the peptide 106-124 somewhat more weakly than ATP. Binding involved residues 115-118 and 121-124, indicating the presence of a reverse turn between these segments. Proton resonances were assigned by using two-dimensional double quantum correlated spectroscopy, one-dimensional spin decoupling techniques, one-dimensional nuclear Overhauser enhancement ...

1987-03-10

396

Gas evolution in aluminum electrolytic capacitors  

Science.gov (United States)

Gas evolution in aluminum electrolytic capacitors constitutes one of their main drawbacks in comparison to other types of capacitors lacking a liquid electrolyte. In this respect, one of the most common causes of failure shown by liquid electrolyte capacitors is electrolyte leakage through the seal or even explosions produced by internal pressure buildup. In order to prevent these hazards, some substances, known as depolarizers, are usually added to the capacitor electrolyte with the purpose of absorbing the hydrogen evolved at the cathode (1, 2). Although the gas evolution problem in electrolytic capacitors has been known for a long time, there is a lack of literature on both direct measurements of the gas evolved and assessments of the amount of depolarizer active for the hydrogen absorption process. Aluminum electrolytic capacitors of 100..mu..F and 40V nominal voltage, miniature type (diam 8 mm, height 18.5 mm), were manufactured under standard specifications. ...

1984-03-01

397

Effects of acid mine drainage on a headwater stream ecosystem in Colorado  

International Nuclear Information System (INIS)

The ecological effects of acid mine drainage were investigated during the summer of 1993 on St. Kevin Gulch, a headwater stream near Leadville, Colorado. The stream currently receives acidic water from an abandoned mine. The pH downstream of the mine is between 3.5 and 4.5, and several metals exceed concentrations toxic to aquatic organisms. Zinc is present at especially high concentrations (1 to 10 mg/L) Furthermore, the stream bottom is covered with a thick layer of iron hydroxide precipitates. Effects on stream biota have been dramatic. Aquatic flora in the affected reach is limited to a green filamentous alga, Ulothrix subtilissima. Macroinvertebrate densities are significantly lower in the affected reach (mean = 99 indiv/m"2; SD = 88 indiv/M"2) compared to an upstream (pristine) reference reach (mean = 1,735 indiv/m"2; SD = 652 indiv/M"2). Functional processes were also studied in the stream. Net primary production (NPP) was measured ...

398

A newly synthesized glycine derivative to control uniform and pitting corrosion processes of Al induced by SCN"- anions - Chemical, electrochemical and morphological studies  

International Nuclear Information System (INIS)

A newly synthesized glycine derivative (termed GlyD), 2-(4-(dimethylamino)benzylamino)acetic acid hydrochloride, was used to inhibit uniform and pitting corrosion processes of Al in 0.50 M KSCN solutions (pH 6.8) at 25 "oC. For uniform corrosion inhibition study, Tafel extrapolation, linear polarization resistance and impedance methods were used, complemented with SEM examinations. An independent method of chemical analysis, namely ICP-AES (inductively coupled plasma atomic emission spectrometry) was also used to test validity of corrosion rate measured by Tafel extrapolation method. GlyD inhibited uniform corrosion, even at low concentrations, reaching a value of inhibition efficiency up to 97% at a concentration of 5 x 10"-"3 M. Results obtained from the different corrosion evaluation techniques were in good agreement. This new synthesized glycine derivative was also used to control pit nucleation and growth on the pitted Al surface based on ...

2010-10-01

399

Repeated laboratory ozone exposures of volunteer Los Angeles residents: an apparent seasonal variation in response  

Energy Technology Data Exchange (ETDEWEB)

This study was intended to help explain individual differences in susceptibility to irritant effects of ozone (O3), by determining whether prior ambient O3 exposures and/or recent acute respiratory illness modified response to laboratory O3 exposures. Response was measured in terms of lung function changes and irritant symptoms. Initially, 59 adult volunteer Los Angeles area residents underwent screening exposures in spring, before the season of frequent high ambient O3 levels. Unusually responsive and nonresponsive individuals (N = 12 and 13 respectively) underwent followup exposures in autumn (late in the high-O3 season) and in winter (low-O3 season). All exposures were to 0.18 ppm O3 for 2 hr with intermittent heavy exercise at 31 degrees C and 35% relative humidity. Nonresponders tended to remain nonresponsive throughout. In fall, responders had lost much of their reactivity, as if they had adapted to summer ambient O3 exposures. They did ...

1988-12-01

400

Determination of radon-222 concentration in inside environments of the Instituto de Engenharia Nuclear, Brazil; Determinacao da concentracao de radonio-222 nos ambientes internos das instalacoes do Instituto de Engenharia Nuclear  

Energy Technology Data Exchange (ETDEWEB)

The gotten concentrations of radon-222 in the installations of the IEN had been determined using the active and passive methods. The active method consisted on the use of the alpha spectrometry with a portable equipment Tracerlab Instruments WLM- Plus. In the determination for the passive method, one used detectors of nuclear strokes of type LEXAN. The raised values had been gotten in the wastes deposit and its annexes, room of the press and laboratory of wastes handling. It was observed, in this sector, an instantaneous measure of alpha spectrometry, concentrations around 1000 Bq.m-3, which had over all to the function of storage, the sector, a great volume of natural radioactive materials, especially of radium-226. This determination was carried through in an extreme situation of ventilation zero, where the gates had been kept closed during the execution of the same one. It was observed, however, a considerable fall, with values ten times ...

2000-07-01

401

A laboratory and field investigation of naphthenic acid corrosion inhibition  

Energy Technology Data Exchange (ETDEWEB)

This paper presents results of a laboratory and field study of naphthenic acid corrosion and the development of an effective chemical inhibitor for this type of corrosive attack. In the laboratory corrosion test, which involved 20 hour weight loss measurements in high flash solvent with a total acid number (TAN) of 16 mg KOH/gm at a temperature of 600 F (316 C), blank corrosion rates averaged 140 to 150 mpy (3.56 to 3.81 mm/y). Inhibited rates averaged about 10 to 12 mpy (0.254 to 0.305 mm/y). The field test was carried out on a heavy vacuum gas oil (HVGO) stream at 550 F (288 C) . Blanks varied from a high of 425 mpy (10.79 mm/y) for a 24 hour test to a low of about 100 mpy (2.54 mm/y) for a 150 hour test. Both electrical resistance (ER) probes and weight loss coupons showed corrosion rates below 5 mpy (0.127 mm/y) as long as they were adequately passivated. Passivation consisted of exposing the coupons to a high inhibitor ...

1995-11-01

402

Measurements of actinides in soil, sediments, water and vegetation in Northern New Mexico  

Energy Technology Data Exchange (ETDEWEB)

This study was undertaken during 1991 - 1998 to identify the origin of plutonium uranium in northern New Mexico Rio Grande and tributary stream sediments. Isotopic fingerprinting techniques help distinguish radioactivity from Los Alamos National Laboratory (LANL) and from global fallout or natural sources. The geographic area covered by the study extended from the headwaters of the Rio Grande in southern Colorado to Elephant Butte Reservoir in southern New Mexico. Over 100 samples of stream channel and reservoir bottom sediments were analyzed for the atom ratios of plutonium and uranium isotopes using thermal ionization mass spectrometry (TIMS). Comparison of these ratios against those for fallout or natural sources allowed for quantification of the Laboratory impact. Of the seven major drainages crossing LANL, movement of LANL plutonium into the Rio Grande can only be traced via Los Alamos Canyon. The majority of sampled locations within and ...

2002-01-01

403

Measurement of magnetic fields in the Area Metropolitana  

International Nuclear Information System (INIS)

The operation and proper handling of equipment for measuring EMR-300 electromagnetic waves are studied and apply that knowledge to determine which areas of the metropolitan area are mostly affected by exposure to the emission of radiation. This team is able to measure magnetic field strength, electric field strength and power density, also can measure the most important parameters in a simple manner. International standards provide maximum values for these parameters that limit human exposure to such radiation. These standards are based on epidemiological several and laboratory that have been carried out in order to determine in which circumstances a biological entity is exposed to a level of radiation that can cause harm to their health. It focuses on measuring the level of radiation in certain areas of interest, which were chosen because are areas with high population density and ...

404

PhET Teacher Ideas and Activities: Images from Convex Lenses  

Science.gov (United States)

This is an inquiry-based module created specifically for use with the PhET simulation Geometric Optics. It includes a lesson plan for teaching about convex lenses, step-by-step student directions, and a set of Power Point "clicker" questions for use as warm-up questions or informal assessment. This resource is part of a larger collection of interactive Java simulations for students of physics, developed by the Physics Education Technology project at the University of Colorado.

2009-05-20

405

Modification of ion-exchange resin composition for the removal of gadolinium from moderator system of 540 MWe PHWRs  

International Nuclear Information System (INIS)

Gadolinium removal during the first approach to criticality of TAPP-4 540 MWe reactor using mixed bed resin (strong acid cation resin and weak base anion resin) topped with strong acid cation exchange resin yielded IX column outlet pH of >6 during the first 6 h of run during which [Gd] decreased from 2.1 to 1 mg/kg. However, the main moderator system pH was between 5.0-5.5. Technical specification for pH of moderator is in the range 5.0-5.5 as long as Gd is present. This is to avoid any precipitation of Gd in the core and a pH of 5.8 or even a pH of 5.6 when carbonate is present is specified as the upper limit of the moderator system pH for this purpose. The situation of IX column outlet pH being #>=# 6 mixing with a system water having Gd results in local mixing zone pH in the range of 6- 5.4. In order to have an ...

2005-11-01

406

Corrosion Behavior of Titanium Grade 7 in Fluoride-Containing NaCl Brines.  

Science.gov (United States)

The effects of fluoride on the corrosion behavior of Titanium Grade 7 (0.12-0.25% Pd) have been investigated. Up to 0.1 mol/L fluoride was added to the NaCl brines at 95oC, and three pH values of 4, 8, and 11 were selected for studying pH dependence of fl...

2004-01-01

407

Contribution of calcium ions and hydrogen ions to the signal transduction chain in phytochrome-mediated spore germination. [Onoclea sensibilis L  

Energy Technology Data Exchange (ETDEWEB)

Red light stimulates germination in the spores of Onoclea sensibilis L. Phytochrome is confirmed to be the photoreceptor pigment in the germination response by demonstrating red-far-red photoreversibility. External Ca/sup 2 +/ is required for this response with a threshold at a submicromolar concentration. Red light stimulates an increase in the total concentration of intracellular calcium in the spores as determined by atomic absorption spectroscopy. Subsequent exposure to far-red light inhibits the red light-induced increase in intracellular calcium. The majority of the increase occurs 5 minutes after the onset of irradiation. The calcium-antagonist, La/sup 3 +/ inhibits both germination and the red light-induced increase in intracellular calcium. Using /sup 31/P-nuclear magnetic resonance spectroscopy, the author tested the hypothesis that a sustained increase in intracellular pH contributes to the signal transduction chain. He never detected a red light-induced ...

1985-01-01

408

31P NMR Observations on the Effect of the External pH on the Intracellular pH Values in Plant Cell Suspension Cultures 1  

UK PubMed Central (United Kingdom)

31P nuclear magnetic resonance (NMR) spectroscopy was used to monitor the response of oil palm (Elaeis guineensis) and carrot (Daucus carota) cell suspensions...Full Text Available

1990-06-01

409

Scale-up of Multidrug-Resistant Tuberculosis Laboratory Services, Peru  

UK PubMed Central (United Kingdom)

Over the past 10 years, the Peruvian National Tuberculosis (TB) Program, the National Reference Laboratory (NRL), Socios en Salud, and US partners have worked to strengthen the national TB laboratory...Full Text Available

2008-05-01

410

Coryneform bacteria in infectious diseases: clinical and laboratory aspects.  

UK PubMed Central (United Kingdom)

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

1990-07-01

411

Native legume establishment on acidic coal mining overburden at Collie, Western Australia  

Energy Technology Data Exchange (ETDEWEB)

Nitrogen is often provided to impoverished overburden dumps through the establishment of legumes. Low indigenous soil nutrient levels, summer drought conditions and an acidic mining overburden represent major obstacles to successful rehabilitation of open-cut coal mining at Collie in southwest Western Australia. In this study, Acacia pulchella, a native Western Australian species often used in rehabilitation of mined lands, was shown to nodulate and grow in coal mining overburden with pH values less than 4.0 under glasshouse conditions. Plant growth (both top and root dry weight), nodule fresh weight, and nodulation success was best at pH near 5.0, a value only slightly lower than the typical soil pH of the native jarrah (Eucalyptus marginata) forest. Acetylene reduction rates were reduced by acidity and ranged from 8.2..mu..m C/sub 2/H/sub 4//g hr at pH 6.77 to 3.0..mu..m C/sub 2/H/sub 4//g hr at a ...

1985-12-01

412

Improved primary water chemistry control of PWR plant in Japan  

International Nuclear Information System (INIS)

Elevated pH operation to the pH value of 7.3 at 285degC is known to be effective for the reduction of radiation source in the primary water system of PWRs. A research project was started in 1989 and concluded in 1996 to study and verify the optimum pH and/or Li concentration from the viewpoint of radiation source reduction and materials integrity under improved water chemistry. This research project is sponsored by the Ministry of International Trade and Industries (MITI) in Japan and has two programs; high pH and high Li. The high Li program was conducted to establish the optimum Li concentration for the high boron concentration region (1100 - 1800 ppm) of the high burn up operation. In this paper, we shall discuss radiation source behavior under high pH conditions and PWSCC (Primary Water Stress Corrosion Cracking) susceptibility of materials with change of primary water chemistry ...

1998-04-01

413

Effect of pH on the phase separation in the ternary aqueous system containing the hydrophilic ionic liquid 1-butyl-3-methylimidazolium bromide and the kosmotropic salt potassium citrate at T=298.15K  

British Library Electronic Table of Contents (United Kingdom)

The goal of this work is to study the effect of the aqueous medium pH on the two-phase equilibrium behaviour of the aqueous {1-butyl-3-methylimidazolium bromide ([C4mim]Br)+potassium citrate} system in order to obtain further information about the salting-out effect produced by the addition of a kosmotropic salt to an aqueous solution of a hydrophilic ionic liquid (IL). For this purpose the phase diagrams and the liquid-liquid equilibrium (LLE) data of the {[C4mim]Br+potassium citrate} aqueous two-phase system (ATPS) were determined experimentally at different pH values. Four medium pH values (5.00, 6.00, 7.00 and 8.00) were assayed at T=298.15K. The effect of pH on the ATPS-promoting capability of citrate anions in the aqueous [C4mim]Br solutions was explained based on the structural hydr...

2011-01-01

414

A conceptual model for laboratory ventilation greenhouse gas planning  

British Library Electronic Table of Contents (United Kingdom)

There is increasing pressure to operate laboratory facilities in environmentally and financially sustainable ways. A key factor in achieving this goal is careful consideration of how energy is used by the buildings' ventilation system, both for conditioning air supplied to the laboratories and the energy used moving air through the building. Traditionally, laboratory energy use is treated as an engineering concern within the scope of the building's overall design and operation. However, this approach limits the involvement of key stakeholders in many important decisions and can lead to unexpected safety concerns for the laboratory's users. We believe that a broad view of the parties affected by a laboratory building's operations is necessary to avoid having the various stakeholders working...

2011-01-01

415

Widespread duplications in the genomes of laboratory stocks of Dictyostelium discoideum  

UK PubMed Central (United Kingdom)

BackgroundDuplications of stretches of the genome are an important source of individual genetic variation, but their unrecognized presence in laboratory organisms would be a confounding...Full Text Available

2008-01-01

416

Today in History: December 17  

Science.gov (United States)

as manufacturing plants and laboratories, including the Chemical Laboratory at the House of David in Benton Harbor, Michigan. Built in America: Historic Building Buildings Survey/...

2010-12-17

417

The Laboratory for Research on the Structure of Matter (LRSM...  

Science.gov (United States)

as one of the first Materials Research Laboratories to be funded by the forerunner of DARPA. In 1972 funding was taken over by the National Science Foundation's Division of...

2011-08-18

418

Savannah River Laboratory monthly report, November 1991  

Energy Technology Data Exchange (ETDEWEB)

This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation; tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)

1991-01-01

419

Savannah River Laboratory monthly report, November 1991  

Energy Technology Data Exchange (ETDEWEB)

This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation; tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)

1991-12-31

420

Pigment Analysis by HPLC at Horn Point Laboratory  

Science.gov (United States)

Oct 30, 2006 ... Pigment Analysis by HPLC at Horn Point Laboratory. Laurie Van Heukelem. Crystal Thomas. Meg Maddox. University of Maryland Center for ...

421

Funding will push battery technology from Argonne Laboratory  

Science.gov (United States)

Publications Science Highlights Researcher Profiles Internship Funding to push battery technology from Argonne Laboratory to marketplace Bookmark and Share (Download...

2011-08-27

422

Thermal modelling of underground coal fires in Northern China  

Energy Technology Data Exchange (ETDEWEB)

The thesis describes work undertaken as part of a larger remote sensing based project which aims to detect, measure and monitor coal fires in two test areas in northern China. The first main topic addressed in this thesis is the detection of fires using several different thermal remote sensing data sets. The synergistic use of the different data sets is emphasised. The second major part of the thesis deals with thermal modelling of the coal fires. Three different models are developed, which allow a fire's depth, temperature, extent, total heat output and rate of movement to be determined. The models are tested both in the laboratory and using various field data sets. A model based on the assumption that the fire is a point heat source and that the temperature distribution around it is spherically symmetrical is shown to be the most effective. A simpler, one-dimensional coal fire model and a model based on the finite element method are ...

1998-07-01

423

The Development of a Neutral Particle Detector for Observations of the Thermosphere  

Science.gov (United States)

One of the least understood regions of the upper atmosphere is the thermosphere, principally due to the difficulty of making observations. The neutral atmosphere is known to be highly variable, and its composition and density varies by several orders of magnitude due to solar activity, diurnal cycles, latitude, geomagnetic activity, and gravity waves. In the past, most in-situ measurements of the neutral atmosphere have utilized detectors that are dependent on arrival angle and energy accommodation of incoming species, so that information related to nascent velocity distribution and reactive species abundances is often masked. This paper will review design concepts and laboratory tests related to the development of a novel open-ionizer, neutral particle detector for space environment measurements which can overcome these limitations. The sensor features a very large field-of-view suitable for sounding rocket missions. ...

2006-12-01

424

The Bunch Injection Controller for the PEP-II Storage Rings  

CERN Document Server

The PEP-II storage rings at SLAC each have 3492 'buckets' into which electrons and positrons can be injected into the high- and low-energy rings. Equipment to measure the currents of all the individual buckets was originally provided by the Lawrence Berkeley Laboratory and is implemented in VXI-based hardware. Data from this equipment as well as high precision direct current measurement provide the hard data for the Bunch Injection Controller. A large number of parameters determined by injection design considerations as well as set by operators for different circumstances are also used by the software algorithms to determine the desired bucket injection order and charge quantity for each injection pulse. These requests are then passed on to the venerable SLAC master pattern generator, which provides beams for other applications as well. This highly visible and highly successful system is implemented using the EPICS toolkit, ...

2001-01-01

425

Synopsis of hydrologic data collected by waste management for characterization of unsaturated transport at Area G  

Energy Technology Data Exchange (ETDEWEB)

Data which have been collected by Los Alamos National Laboratory waste management for the hydrologic characterization of the subsurface at the low level radioactive waste disposal facility, Area G, are reported and discussed briefly. The data includes Unsaturated Flow Apparatus measurements of the unsaturated conductivity in samples from borehole G-5. Analysis compares these values to the predictions from van Genuchten estimates, and the implications for transport and data matching are discussed, especially at the location of the Vapor Phase Notch (VPN). There, evaporation drives a significant vapor flux and the liquid flux cannot be measured accurately by the UFA device. Data also include hydrologic characterization of samples from borehole G-5, Area G surface soils, Los Alamos (Cerros de Rio) basalt, Tsankawi and Cerro-Toledo layers, the Vapor Phase Notch (VPN), and additional new samples from the uppermost tuff layer at ...

1998-03-01

426

Study of the Photon Strength Functions for Gadolinium Isotopes with the DANCE Array  

Science.gov (United States)

The gadolinium isotopes are interesting for reactor applications as well as for medicine and astrophysics. The gadolinium isotopes have some of the largest neutron capture cross sections. As a consequence they are used in the control rod in reactor fuel assembly. From the basic science point of view, there are seven stable isotopes of gadolinium with varying degrees of deformation. Therefore they provide a good testing ground for the study of deformation dependent structure such as the scissors mode. Decay gamma rays following neutron capture on Gd isotopes are detected by the DANCE array, which is located at flight path 14 at the Lujan Neutron Scattering Center at Los Alamos National Laboratory. The high segmentation and close packing of the detector array enable gamma-ray multiplicity measurements. The calorimetric properties of the DANCE array coupled with the neutron time-of-flight technique enables one to gate on a specific resonance of a ...

2009-03-10

427

Shallow hydrothermal regime of the East Brawley and Glamis known geothermal resource areas, Salton Trough, California  

Energy Technology Data Exchange (ETDEWEB)

Thermal gradients and thermal conductivities were obtained in real time using an in situ heat-flow technique in 15 shallow (90 to 150 m) wells drilled between Brawley and Glamis in the Imperial Valley, Southern California. The in situ measurements were supplemented by follow-up conventional temperature logs in seven of the wells and by laboratory measurements of thermal conductivity on drill cuttings. The deltaic sedimentary material comprising the upper approx. 100 m of the Salton Trough generally is poorly sorted and high in quartz resulting in quite high thermal conductivities (averaging 2.0 Wm/sup -1/ K/sup -1/ as opposed to 1.2 to 1.7 for typical alluvium). A broad heat-flow anomaly with maximum of about 200 mWm/sup -2/ (approx. 5 HFU) is centered between Glamis and East Brawley and is superimposed on a regional heat-flow high in excess of 100 mWm/sup -2/ (> 2.5 HFU). The heat-flow high corresponds with a gravity ...

1981-01-01

428

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 < ...

2006-11-01

429

Optimal alignment of mirror based pentaprisms for scanning deflectometric devices  

Science.gov (United States)

In the recent work [Proc. of SPIE 7801, 7801-2/1-12 (2010), Opt. Eng. 50(5) (2011), in press], we have reported on improvement of the Developmental Long Trace Profiler (DLTP), a slope measuring profiler available at the Advanced Light Source Optical Metrology Laboratory, achieved by replacing the bulk pentaprism with a mirror based pentaprism (MBPP). An original experimental procedure for optimal mutual alignment of the MBPP mirrors has been suggested and verified with numerical ray tracing simulations. It has been experimentally shown that the optimally aligned MBPP allows the elimination of systematic errors introduced by inhomogeneity of the optical material and fabrication imperfections of the bulk pentaprism. In the present article, we provide the analytical derivation and verification of easily executed optimal alignment algorithms for two different designs of mirror based pentaprisms. We also provide an analytical description for the ...

2011-03-04

430

Nuclear forensics-metrological basis for legal defensibility  

International Nuclear Information System (INIS)

The admissibility of nuclear forensics measurements and opinions derived from them in US Federal and State courts are based on criteria established by the US Supreme Court in the case of Daubert v. Merrell Dow and the 2000 Amendment of Rule 702 of the Federal Rules of Evidence. These criteria are being addressed by new efforts that include the development of certified reference materials (CRMs) to provide the basis for analytical method development, optimization, calibration, validation, quality control, testing, readiness, and declaration of measurement uncertainties. Quality data is crucial for all stages of the program, from R and D, and database development, to actual casework. Weakness at any point in the program can propagate to reduce the confidence of final conclusions. The new certified reference materials will provide the necessary means to demonstrate a high level of metrological rigor for nuclear forensics evidence and will form a ...

2009-12-01

431

Inventory of tritium concentration of waters in the Manche department; Inventaire des concentrations en tritium des eaux du Departement de La Manche  

Energy Technology Data Exchange (ETDEWEB)

For the inventory of water tritium concentration in the Manche department, it is the complementarity that animated the work opened during year 2001. To answer to a commune sensitivity such water quality, particularly drinking water at tap, the A.C.R.O. laboratory brought its know how to make and its technical means in the area of tritium analysis and the general council brought its know how to make and its logistics means in matter of sanitary control. This collaboration has allowed to supply an indication on the tritium content of the distribution waters of thirty of the most important cities of the department. Then, it allowed to inform on the radiological situation (in relation with the tritium presence) of coast waters and principal rivers waters. More than 160 controls have been realised between the months of march 2001 and february 2002. Only the tritium under the shape of tritiated water has been measured. The ...

2007-07-01

432

Identifying primary stressors impacting macroinvertebrates in the Salinas River (California, USA): Relative effects of pesticides and suspended particles  

International Nuclear Information System (INIS)

Laboratory dose-response experiments with organophosphate and pyrethroid pesticides, and dose-response experiments with increasing particle loads were used to determine which of these stressors were likely responsible for the toxicity and macroinvertebrate impacts previously observed in the Salinas River. Experiments were conducted with the amphipod Hyalella azteca, the baetid mayfly Procloeon sp., and the midge Chironomus dilutus (Shobanov, formerly Chironomus tentans). The results indicate the primary stressor impacting H. azteca was pesticides, including chlorpyrifos and permethrin. The mayfly Procloeon sp. was sensitive to chlorpyrifos and permethrin within the range of concentrations of these pesticides measured in the river. Chironomus dilutus were sensitive to chlorpyrifos within the ranges of concentrations measured in the river. None of the species tested were affected by turbidity as high as 1000 NTUs. The current ...

2006-06-01

433

Evaluation of light-water-moderated, mixed-oxide, hexagonal pitch lattices  

International Nuclear Information System (INIS)

The use of previously measured mixed-oxide (MOX) fuel systems as benchmarks can be valuable tool in computational analysis and quality assurance efforts. The Fissile Materials Disposition Program (FMDP) has identified these experiments as potential benchmarks, or standards, for VVER's employing MOX fuel. Standards for the analysis of these benchmark experiments were based on those used in the recent compilation International Handbook of Evaluated Criticality Safety Benchmark Experiments begun in 1992 by the U.S. Department of Energy. The Los Alamos National Laboratory's archives were explored for log-book records of these experiments without success. These experiments were the first to use MOX fuel in light water. Three approach-to-critical experiments were performed using fuel rods at various pitches and different plutonium-oxide concentrations. A parallel program verified the prediction of critical condition as similar materials and ...

1997-11-16

434

Evaluating created wetlands through comparisons with natural wetlands  

Energy Technology Data Exchange (ETDEWEB)

The report summarizes the evaluation and recommendations regarding an approach to wetland sampling and characterization developed by the Wetlands Research Program (WRP) at U.S. Environmental Protection Agency, Environmental Research Laboratory, Corvallis, OR. Between trials, team members discussed at length the methodology and field protocols and modified them to reflect the conditions and difficulties encountered in sampling herbaceous wetlands in urban areas of Florida. Major emphasis is placed on the appropriateness of measured variables for determining successful wetland re-creation. Numerous physical and biological parameters were measured and compared in the nine created and nine natural wetlands. Analysis of these data has shown some important similarities and differences between created and natural wetlands and lends insight into the complex questions surrounding wetland creation and the equivalency of created ...

1991-11-01

435

Environmental status of Technical Area 49, Los Alamos, New Mexico  

Energy Technology Data Exchange (ETDEWEB)

A series of experiments involving high explosives and radioactive materials were conducted at Los Alamos, New Mexico, primarily to understand certain safety aspects of operational nuclear weapons. The experiments were conducted underground in large diameter holes as deep as 120 ft. The location was selected because it had geologic and hydrologic characteristics that assured complete containment of the experiments and precluded any possible contamination of groundwater. Important features verified by the USGS included the absence of any recharge and about 1200 feet of dry rock above the groundwater aquifer. Residual materials dispersed by detonation of the high explosives remain at the bottom of the experimental holes. The materials of significance from an environmental standpoint include about 40 kg of plutonium, 93 kg of enriched uranium, at least 82 kg of depleted uranium, 13 kg of beryllium, and an undetermined amount of lead. Environmental monitoring has been carried out regularly ...

1987-11-01

436

Emittance of boehmite and alumina films on 6061 aluminium alloy between 295 and 773 K  

Energy Technology Data Exchange (ETDEWEB)

The total hemispherical emittance of an oxide film that formed on 6061-T6 aluminium alloy parts in the Tower Shielding Reactor-II at Oak Ridge National Laboratory was measured from 295 to 773 K using an emissometer and/or a calorimeter. The emittance of this film was critically needed for heat transfer calculations in a simulated loss-of-coolant accident of the reactor. X-ray diffraction analysis identified the film as boehmite (Al{sub 2}O{sub 3} {times} H{sub 2}O), which dehydrated to alumina (Al{sub 2}O{sub 3}) upon heating above 473 K. The measured emittances for the alumina film are in excellent agreement with published values for anodized aluminum films and for bulk alumina. Published values of the emittance of boehmite could not be found for comparison, but evidence is presented that some anodization processes for aluminum yield boehmite and not alumina films.

1991-02-01

437

Damage to metallic samples produced by measured lightning currents  

Energy Technology Data Exchange (ETDEWEB)

A total of 10 samples disks of 2024-T3 aluminum and 4130 ferrous steel were exposed to rocket-triggered lightning currents at the Kennedy Space Center test site in Florida during the summer of 1990. The experimental configuration was arranged so that the samples were not exposed to the preliminary streamer, wire-burn, or following currents that are associated with an upward-initiated rocket-triggered flash but which are a typical of naturally initiated lightning. Return-stroke currents and continuing currents actually attaching to the sample were measured, augmented by close-up video recordings of approximately 3 feet of the channel above the sample and by 16-mm movies with 5-ms resolution. From these data it was possible to correlate individual damage spots with streamer, return-stroke, and continuing currents that produced them. Substantial penetration of 80-mil aluminum was produced by a continuing current of submedian amplitude and duration, and full ...

1991-01-01

438

Combined Scanning Electron Microscope and Micro-InfraRed measurements on Interplanetary Dust Particles  

CERN Document Server

Laboratory characterization of Interplanetary Dust Particles (IDPs) collected in the lower stratosphere represents a concrete analysis of cosmic dust properties which played a fundamental role in the origin and evolution of Solar System. The IDPs were characterized by Field Emission Scanning Electron Microscope (FESEM) analyses and by InfraRed (IR) micro-spectroscopy. We present the FESEM images of six IDPs: three smooth grains, two porous and one a compact sphere. We also show the results of micro-IR transmission measurements on four IDPs that allowed us to identify their spectral class according to the criteria defined by Sandford and Walker. Only three of the analyzed particles show IR transmission spectra with a dominant "silicate absorption feature" so that they could be assigned to the three IR spectral classes: one has been classified as "amorphous olivine", one appears to be a mixture of "olivines" and "pyroxenes" and one belongs to the ...

2007-01-01

439

Brine chemistry and control of adverse chemical reactions with natural gas production. Annual report, January-December 1986  

Energy Technology Data Exchange (ETDEWEB)

Monitoring brine chemistry to determine the extent of potential adverse reactions has been simplified by the development of a field-brine test kit and a series of nomographs. Results of the kit analyses serve as input to the nomographs, which provide a graphic means of determining the scaling tendency (Saturation Index value) of a brine. Brines that do not tend to form scale may be corrosive. Saturation Index values were correlated with various processes using data from geopressured wells in the Gulf Coast area. Control of scale in surface equipment with chemical inhibitors has been successful. Numerous laboratory simulations of inhibitor squeeze operations were completed using core material with calcite present and absent. The corresponding wells were squeezed with phosphorous-containing inhibitors, and the flowback of brine was monitored for phosphorous concentrations vs time. A new procedure to measure the concentration of ...

1987-01-01

440

Assessment of a non-dedicated GPS receiver system for precise airborne attitude determination  

Energy Technology Data Exchange (ETDEWEB)

The use of a non-dedicated GPS receiver system for attitude determination was assessed in airborne mode through a test conducted at Sandia National Laboratories. Four independent NovAtel GPSCard{trademark} receivers were installed in Sandia`s Twin Engine Otter with two antennas mounted on the fuselage and two on the wing tips at separations of 6 to 18 m. A strapdown INS was also on board the aircraft in order to provide an independent attitude reference at rates between 4 and 10 Hz. During the multi-day test, GPS measurements were recorded between 1 and 10 Hz. Carrier phase measurements were post-processed using a double difference approach developed at The University of Calgary in which integer ambiguities were resolved in seconds using the known antenna separations as constraints. The tracking capability of the system is demonstrated under dynamics consisting of roll and pitch angles up to 45 and 12 degrees, respectively. ...

1994-09-01

441

An ecologically relevant exposure assessment for a polluted river using an integrated multivariate PLS approach  

International Nuclear Information System (INIS)

A case study is presented where an integrated, ecologically relevant exposure assessment is presented for a polluted lowland river. Using partial least squares regression of latent structures (PLS), an analysis of the impact of two effluents on physico-chemical water quality measures, macroinvertebrate and diatom communities, and in situ bioassay responses with four different test species are combined into an integrative exposure assessment. Bioassays focussed on growth and condition related endpoints, because they are key functional processes of organisms and populations. Integrating these multiple lines of evidence, we were able to discriminate among the impact of both effluents, link changes in physico-chemical water quality with bioassay endpoints and ecological quality of the ecosystem, and address the importance of integrating all information into one exposure assessment framework. The bioassays under field conditions indicated that most endpoints ...

2004-11-01

442

A new approach towards anomalous fading correction for feldspar IRSL dating - tests on samples in field saturation  

Energy Technology Data Exchange (ETDEWEB)

Anomalous fading of the feldspar infrared stimulated luminescence (IRSL) signal hampers possibilities of using feldspar IRSL to obtain burial ages for sediments beyond the dating range of quartz optically stimulated luminescence. Here, we propose a new approach to quantify anomalous fading of the feldspar IRSL signal over geological burial times based on laboratory fading experiments. The approach builds on the description of the quantum mechanical tunnelling process recently proposed by Huntley [2006. An explanation of the power-law decay of luminescence. J. Phys. Condensed Matter 18, 1359-1365]. We show that our methods allow the construction of un-faded and natural IRSL dose-response curves as well as anomalous fading rates in field saturation. The predicted level of field saturation closely approximates the measured saturation level for five samples from fluvial deposits (Lower Rhine) known to be older than 1 Ma. The modelled anomalous ...

2008-02-15

443

A Wide-Band Electromagnetic Impedance Profiling System forNon-Invasive Subsurface Characterization  

Energy Technology Data Exchange (ETDEWEB)

A non-invasive, wide-band electromagnetic (EM) impedance difference system for shallow subsurface electrical structure characterization in environmental and engineering problems has been developed at the Lawrence Berkeley National Laboratory (LBNL). Electrical parameters of interest are electrical conductivity and dielectric permittivity that are deduced from the impedance difference data. The prototype system includes a magnetic loop transmitter, which operates between 0.1 MHz and 100 MHz, an electrical dipole antenna for observing the electric field, and a loop antenna for measuring the magnetic field.All antennas are mounted on a cart made of non-metallic material for easy movement of the whole array for profiling. Surface EM impedance difference is obtained by taking the difference of the ratios of the electric fields to the magnetic fields at selected frequencies at two different levels. Numerical simulations will be presented to verify ...

2004-12-17

444

A New Measurement of Kaonic Hydrogen X rays  

CERN Document Server

The $\\bar{K}N$ system at threshold is a sensitive testing ground for low energy QCD, especially for the explicit chiral symmetry breaking. Therefore, we have measured the $K$-series x rays of kaonic hydrogen atoms at the DA$\\Phi$NE electron-positron collider of Laboratori Nazionali di Frascati, and have determined the most precise values of the strong-interaction energy-level shift and width of the $1s$ atomic state. As x-ray detectors, we used large-area silicon drift detectors having excellent energy and timing resolution, which were developed especially for the SIDDHARTA experiment. The shift and width were determined to be $\\epsilon_{1s} = -283 \\pm 36 \\pm 6 {(syst)}$ eV and $\\Gamma_{1s} = 541 \\pm 89 {(stat)} \\pm 22 {(syst)}$ eV, respectively. The new values will provide vital constraints on the theoretical description of the low-energy $\\bar{K}N$ interaction.

2011-01-01

445

Tomography and Methods of Travel-Time Calculation for Regional Seismic Location  

Energy Technology Data Exchange (ETDEWEB)

We are developing a laterally variable velocity model of the crust and upper mantle across Eurasia and North Africa to reduce event location error by improving regional travel-time prediction accuracy. The model includes both P and S velocities and we describe methods to compute travel-times for Pn, Sn, Pg, and Lg phases. For crustal phases Pg and Lg we assume that the waves travel laterally at mid-crustal depths, with added ray segments from the event and station to the mid crustal layer. Our work on Pn and Sn travel-times extends the methods described by Zhao and Xie (1993). With consideration for a continent scale model and application to seismic location, we extend the model parameterization of Zhao and Xie (1993) by allowing the upper-mantle velocity gradient to vary laterally. This extension is needed to accommodate the large variation in gradient that is known to exist across Eurasia and North African. Further, we extend the linear travel-time calculation method to mantle-depth ...

2007-07-02

446

Relationship between acute ozone responsiveness and chronic loss of lung function in residents of a high-ozone community  

Energy Technology Data Exchange (ETDEWEB)

The authors hypothesized that acute respiratory responsiveness to ozone predicts chronic lung injury from repeated exposure to ozone-containing air pollution. They tested this hypothesis in 164 middle-aged nonsmoking residents of an ozone-polluted community who underwent lung-function measurements during 1986 and 1987 (i.e., time 3). The time-3 study was a follow up of more comprehensive studies conducted in 1977--1978 (time 1) and in 1982--1983 (time 2). In contrast to the apparent rapid (i.e., {approx} 60 ml/y) decline in lung-function measurements between times 1 and 2, their subjects showed little change in forced vital capacity (FVC) or forced expired volume in 1 s (FEV{sub 1.0}) between times 2 and 3, and they experienced a normal decline between times 1 and 3. A subgroup (n = 45) underwent 2-h laboratory ozone exposures to 0.4 ppm ozone, accompanied by intermittent exercise, and they experienced mild acute reductions ...

1998-09-01

447

Heavy fuel oil combustion in a cylindrical laboratory furnace: measurements and modeling  

Energy Technology Data Exchange (ETDEWEB)

The finite-volume based commercial CFD-code Fluent was used to simulate the reacting flow in a heavy fuel oil fired laboratory furnace. Both the standard {kappa}-{epsilon} turbulence model and the Reynolds stress model (RSM) were tested. The combustion model was based on the conserved scalar (mixture fraction) and prescribed probability density function approach. The heavy fuel oil droplet trajectories were predicted by solving the momentum equations for the droplets using the Lagrangian treatment. The soot distribution in the furnace was calculated by solving a transport equation for the soot mass fraction. Simple expressions for the soot formation and oxidation rates were employed. The radiation heat transfer equation was solved using the finite volume method. The formation of thermal NO from molecular nitrogen was modeled according to the extended Zeldovich mechanism. Fuel-based NO was modeled assuming that all the nitrogen in the fuel is released as hydrogen ...

2005-03-01

448

Studies of aerosol formation in power plant plumes - II. Secondary aerosol formation in the Navajo generating station plume  

Energy Technology Data Exchange (ETDEWEB)

Aerosol and gas measurements were made with the University of Minnesota Mobile Laboratory (UMML) during the VISTTA programme near Page, Arizona. The UMML was stationed on Zilnez Mesa approx. 65 km east of the Navajo coal-fired power plant. Measurements were made both in and out of the power plant plume and were made during the day and night. Measured parameters included aerosol size distributions, Aitken nuclei count, ozone and sulphur dioxide concentrations, the aerosol light scattering coefficient, and meteorological parameters including ultraviolet radiation intensity. Concentrations of NO and NO/SUB/x were occasionally measured. Data show clear evidence of gas-to-particle conversion in the plume with aerosol volume being added in the 0.01 MUm - 0.32 MUm dia. range and new particles being formed. The observed excess aerosol volume depends strongly upon the SO/SUB/2 concentrations ...

1981-01-01

449

Radon emanation and soil moisture effects on airborne gamma-ray measurements  

Energy Technology Data Exchange (ETDEWEB)

A theoretical model is developed to explain variations in airborne gamma-ray measurements over a calibration range near Ottawa, Ontario. The gamma-ray flux from potassium and the thorium decay series showed an expected decrease with increasing soil moisture. However, the gamma-ray flux from the uranium decay series was highest in the spring when the ground was water-saturated and even covered with snow. These results are explained through the build-up of radon and its associated gamma-ray-emitting decay products in the clay soil of the calibration range with increasing soil moisture. Similar results were found from airborne measurements over other clay soils. However, measurements over sandy soils showed that the count rates from all three radio elements increased with decreasing soil moisture. This difference between soil types was attributed to the lower radon emanation of the more coarse-grained sandy soils compared to ...

1997-09-01

450

Radon emanation and soil moisture effects on airborne gamma-ray measurements  

International Nuclear Information System (INIS)

A theoretical model is developed to explain variations in airborne gamma-ray measurements over a calibration range near Ottawa, Ontario. The gamma-ray flux from potassium and the thorium decay series showed an expected decrease with increasing soil moisture. However, the gamma-ray flux from the uranium decay series was highest in the spring when the ground was water-saturated and even covered with snow. These results are explained through the build-up of radon and its associated gamma-ray-emitting decay products in the clay soil of the calibration range with increasing soil moisture. Similar results were found from airborne measurements over other clay soils. However, measurements over sandy soils showed that the count rates from all three radio elements increased with decreasing soil moisture. This difference between soil types was attributed to the lower radon emanation of the more coarse-grained sandy soils compared to ...

451

Measurements of water vapor adsorption on the Geysers rocks  

Energy Technology Data Exchange (ETDEWEB)

The ORNL high temperature isopiestic apparatus was adapted for adsorption measurements. The quantity of water retained by rock samples taken from three different wells of The Geysers was measured at 150 °C and at 200 °C as a function of pressure in the range 0.00 ≤ p/p0 ≤ 0.98, where p0 is the saturated water vapor pressure. The rocks were crushed and sieved into three fractions of different grain sizes (with different specific surface areas). Both adsorption (increasing pressure) and desorption (decreasing pressure) runs were made in order to investigate the nature and extent of the hysteresis. Additionally, BET surface area analyses were performed by Porous Materials Inc. on the same rock samples using nitrogen or krypton adsorption measurements at 77 K. Specific surface areas and pore volumes were determined. These parameters are important in ...

1996-01-24

452

High-speed surface temperature measurements on plasma facing materials for fusion applications  

International Nuclear Information System (INIS)

For the lifetime evaluation of plasma facing materials in fusion experimental machines, it is essential to investigate their surface behavior and their temperature responses during an off-normal event such as the plasma disruptions. An infrared thermometer with a sampling speed as fast as 1x10"-"6 s/data, namely, the high-speed infrared thermometer (HSIR), has been developed by the National Research Laboratory of Metrology in Japan. To evaluate an applicability of the newly developed HSIR on the surface temperature measurement of plasma facing materials, high heat flux beam irradiation experiments have been performed with three different materials under the surface heat fluxes up to 170 MW/m"2 for 0.04 s in a hydrogen ion beam test facility at the Japan Atomic Energy Research Institute. As for the results, HSIR can be applicable for measuring the surface temperature responses of the armor tile materials with a little ...

453

Evaluation of methods to measure surface level in waste storage tanks: Second test sequence  

Energy Technology Data Exchange (ETDEWEB)

This report describes the results of a program conducted at the Pacific Northwest Laboratory (PNL) and Westinghouse Hanford Company (WHC) to identify alternative methods to measure the surface level in the waste tanks. This program examined commercially available devices for measuring the distance to a target. This is a continuation of a program started in FY93. In the first test sequence, tests were performed.on five devices to determine their applicability to measure the surface level in the waste tanks. The devices were the Enraf-Nonius{trademark} Model 872 Radar Gauge, the Enraf-Nonius{trademark} Model 854 Advanced Technology Gauge (ATG), the Stanley Tool Laser Measuring Device, the Robertshaw Inven-Tel{reg_sign} Precision Level Gauge, and the Micro Switch Model 942 Acoustic Sensor. In addition, discussions were held with several manufacturer representatives regarding other ...

1993-09-01

454

A comprehensive understanding of the efficacy of N-Ring hardening methodologies in SiGe HBTs  

International Nuclear Information System (INIS)

We investigate the efficacy of mitigating radiation-based single event effects (SEE) within circuits incorporating SiGe heterojunction bipolar transistors (HBTs) built with an N-Ring, a transistor-level layout-based radiation hardened by design (RHBD) technique. Previous work of single-device ion-beam induced charge collection (IBICC) studies has demonstrated significant reductions in peak collector charge collection and sensitive area for charge collection; however, few circuit studies using this technique have been performed. Transient studies performed with Sandia National Laboratory's (SNL) 36 MeV 16O microbeam on voltage references built with N-Ring SiGe HBTs have shown mixed results, with reductions in the number of large voltage disruptions in addition to new sensitive areas of low-level output voltage disturbances. Similar discrepancies between device-level IBICC results and circuit measurements are found for the case of digital shift ...

2010-07-19

455

(Fast neutron cross section measurements)  

Energy Technology Data Exchange (ETDEWEB)

In the 14 MeV Neutron Laboratory, we have continued the development of a facility that is now the only one of its kind in operation in the United States. We have refined the klystron bunching system described in last year's report to the point that 1.2 nanosecond pulses have been directly measured. We have tested the pulse shape discrimination capability of our primary NE 213 neutron detector. We have converted the RF sweeper section of the beamline to a frequency of 1 MHz to replace the function of the high voltage pulser described in last year's report which proved to be difficult to maintain and unreliable in its operation. We have also overcome several other significant experimental difficulties, including a major problem with a vacuum leak in the main accelerator column. We have completed additional testing to prove the remainder of the generation and measurement systems, but overcoming some of these ...

1991-01-01

456

Delayed neutron energy spectra following fast fission of "2"3"8U  

International Nuclear Information System (INIS)

Delayed neutron energy spectra have been measured for six delay-time intervals following the fast fission of "2"3"8U nuclei. The delay-time intervals span the range 0.17 to 10.2 seconds following initial fission while the measured spectra span neutron energies from 10 keV to 4 MeV. The experiment was performed utilizing the UMass/Lowell 5.5 MV Van de Graff accelerator to produce fast neutrons for inducing fission in a "2"3"8U lined fission chamber. The fission fragments were flushed via a helium jet stream to a well-shielded counting room where they were deposited onto a moving tape (magnetic audio tape) and transferred to a beta-neutron time-of-flight spectrometer. By adjusting the tape speed, composite delayed neutron time-of-flight spectra were measured for several different delay-time intervals. These measurements involved beta-neutron coincidences with "6Li-loaded glass scintillators for neutron ...

457

Effects of pH and phosphate on metal distribution with emphasis on As speciation and mobilization in soils from a lead smelting site  

Energy Technology Data Exchange (ETDEWEB)

Arsenic in soils from the Asarco lead smelter in East Helena, Montana was characterized by X-ray absorption spectroscopy (XAS). Arsenic oxidation state and geochemical speciation were analyzed as a function of depth (two sampling sites) and surface distribution. These results were compared with intensive desorption/dissolution experiments performed in a pH stat reactor for samples from the site with the highest degree of As heterogeneity. The objectives of the study were to investigate the solid-phase geochemical As speciation, assess the speciation of As in solutions equilibrated with the solids under controlled pH (pH=4 or 6) and Eh (using hydrogen or air) environments, observe the effects of phosphate on the release of As into solution, and examine the effects of phosphate on metal mobility in the systems. Arsenic was predominantly found in the As(V) valence state, though there was evidence that As(III) and As(0) were ...

2005-06-01

458

Decolorization of basic, direct and reactive dyes by pre-treated narrow-leaved cattail (Typha angustifolia Linn.).  

Science.gov (United States)

The efficiency of basic, direct and reactive dye removal from water by narrow-leaved cattail (NLC) powder treated with distilled water (DW-NLC), 37% formaldehyde+0.2 N sulfuric acid (FH-NLC), or 0.1 N sodium hydroxide (NaOH-NLC) at various pH levels (3, 5, 7, and 9) was tested. Desorption of the adsorbed dyes was also investigated. The type of NLC treatment and pH of the dye solution had little effect on removal of basic dyes, and efficiencies ranged from 97% to 99% over the range of pH used. Over a wide range of pH levels, all types of treated cattail powder had negative charges and probably attracted the basic dyes possessing positive charges. Efficiency of removal by the three NLC treatments ranged from 37% to 42% for direct dyes and from 22% to 54% for direct dyes at pH 7. The pH of the dye solution had substantial effects on the efficiency of removal in ...

2004-09-01

459

SOLVENT EXTRACTION OF CESIUM BY DIPICRYLAMINE. III. SEMIWORKS DEMONSTRATION  

Science.gov (United States)

The extraction and recovery of cesium from simulated Purex waste solutions was successfully demonstrated in the pilot plant pulse column. Stable volumetric capacities as high as 670 gph/ft/sup 2/ (sum of both phases) were obtained for alkaline supernate-type waste; however, for efficient operation (transfer unit height - HTU -of two feet or less), the maximum throughput rate was limited to about 500 gph/ft/sup 2/. This rate could be achieved with feeds diluted to densities within 0.08 g/cc of the solvent density. Stable feed was prepared from simulated current, denitrated waste by addition of citric acid to complex the iron before neutralization to the desired operating pH of 7 to 8. Capacities of 500 gph/ft/sup 2/ were readily achieved with this feed, together with HTU's of 1.0 to 1.3 feet. Sodium extracted with the cesium was satisfactorily scrubbed from the solvent with a dilute citric acid solution. Scrub section sodium ...

1963-03-15

460

Plasma nitriding and plasma nitrocarburizing of electroplated hard chromium to increase the wear and the corrosion properties  

Energy Technology Data Exchange (ETDEWEB)

We have investigated the effect of plasma nitriding and plasma nitrocarburizing on the microstructure and properties of electroplated chromium. Plasma nitriding and plasma nitrocarburizing are applied to 15-100 [mu]m thick electroplated hard chromium coatings to increase both the wear and the corrosion resistance. The properties of the plasma-modified hard chromium layers are characterized by measuring the wear resistance with a Taber wear tester and the corrosion resistance with a salt spray fog test. Cyclic voltammetry is performed in a standard electrochemical cell using a 0.5 M H[sub 2]SO[sub 4] solution acidified to pH 0.3. The compound layer after plasma nitriding consists of CrN and Cr[sub 2]N with a maximum hardness of about 1100 HK[sub 0.01]. After plasma nitrocarburizing, Cr[sub 3]C[sub 2] and Cr[sub 7]C[sub 3] are formed. After plasma nitrocarburizing, the maximum hardness is increased up to 2200 HK[sub 0.01]. The wear rate is ...

1999-02-01

461

Peroxi-coagulation degradation of C.I. Basic Yellow 2 based on carbon-PTFE and carbon nanotube-PTFE electrodes as cathode  

International Nuclear Information System (INIS)

The electrochemical treatment of solutions containing C.I. Basic Yellow 2 (BY2) in aqueous solutions with carbon-PTFE (polytetrafluoroethylene) and carbon nanotube (CNT)-PTFE electrodes as cathode has been studied. The fabricated electrodes were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The amount of electrogenerated H2O2 on the surface of these electrodes was investigated, too. The results showed that the amount of H2O2 obtained with the CNT-PTFE electrode was nearly three times higher than that of carbon-PTFE electrode. The decolorization efficiency of BY2 in peroxi-coagulation process reached 62% and 96% in the first 10 min by carbon-PTFE and CNT-PTFE electrodes at 100 mA, respectively. The effect of operational parameters such as applied current, initial pH and initial dye concentration was studied in an attempt to reach higher decolorization efficiency. The degradation and mineralization of BY2 using CNT-PTFE ...

2009-11-01

462

Permafrost at Lupin: Report of Phase II  

International Nuclear Information System (INIS)

The aim of the project is to study the conditions and processes occurring in permanently frozen crystalline bedrock, with special reference to deep (i.e., several hundreds of meters) bedrock conditions. The target of the study is the Lupin mine in Nunavut Territory, Northern Canada. The results may be utilized in assessing the long-term performance of deep underground constructions (e.g., nuclear waste repositories) in cooling climatic conditions. In Phase I of the project versatile background information was collected from the site e.g., on climate, geology and on hydrogeological and hydrogeochemical conditions. During Phase II a broad range of research was conducted including (i) electromagnetic soundings to investigate the distribution of permafrost in the surroundings of the mine; (ii) drilling of three research boreholes at the base of the permafrost for groundwater research; (iii) application of borehole video surveys to study the distribution of open fracturing and iv) sealing ...

2004-01-01

463

Kinetic, spectroscopic and chemical modification study of iron release from transferrin; iron(III) complexation to adenosine triphosphate  

Energy Technology Data Exchange (ETDEWEB)

Amino acids other than those that serve as ligands have been found to influence the chemical properties of transferrin iron. The catalytic ability of pyrophosphate to mediate transferrin iron release to a terminal acceptor is largely quenched by modification non-liganded histine groups on the protein. The first order rate constants of iron release for several partially histidine modified protein samples were measured. A statistical method was employed to establish that one non-liganded histidine per metal binding domain was responsible for the reduction in rate constant. These results imply that the iron mediated chelator, pyrophosphate, binds directly to a histidine residue on the protein during the iron release process. EPR spectroscopic results are consistent with this interpretation. Kinetic and amino acid sequence studies of ovotransferrin and lactoferrin, in addition to human serum transferrin, have allowed the tentative assignment of His-207 in the ...

1985-01-01

464

Isolation of imidacloprid degrading bacteria from industrial sites  

International Nuclear Information System (INIS)

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

465

Instrumentation for monitoring and control of water chemistry for light-water-cooled nuclear power plants  

Energy Technology Data Exchange (ETDEWEB)

Based on the IAPWS technical guidance on ''Instrumentation for Monitoring and Control of Cycle Chemistry for Steam-Water Circuits of Fossil-Fired and Combined Cycle Power Plants,'' the latest situation regarding instrumentation for nuclear power plants is discussed. As a result of the discussion, it is concluded that: (1) Reliable and safe operation of plants is established by the application of suitable chemical conditions in plant cooling systems, which should be supported by the selection of suitable control targets for monitoring and by the application of reliable instruments. (2) The minimum level of key instrumentation consists of on-line as well as off-line instruments for monitoring the key parameters: - on-line: pH, conductivity, cation conductivity, O{sub 2} and H{sub 2} concentrations, electrochemical corrosion potential; - off-line: radioactive nuclides ({sup 60}Co, {sup 58}Co, {sup 131}I, etc.), and the ...

2010-05-15

466

In situ scanning tunneling microscope study of the passivation of Cu(111)  

Energy Technology Data Exchange (ETDEWEB)

In situ scanning tunneling microscopy has been used to study the nucleation and growth mechanisms and the structure of passive films formed on Cu(111) surfaces in 0.1 M borate buffer solution (pH 9.3). A surface topography characterized by terraces with monoatomic steps is obtained after potentiodynamic reduction down to {minus}1.12 V/standard hydrogen electrode (SHE), of the electropolished surface exposed to air. The formation of a single Cu{sub 2}O passive layer at 0.03 V/SHE proceeds first by a roughening of the steps assigned to a locally blocked step flow process due to a competition between dissolution and preferential nucleation of the oxide at the steps. The observed oxide nuclei are 2--3 nm wide and about one atomic plane high. This process leads to the complete coverage of the terraces by a grain-like structure of the oxide film. The initial terrace topography is completely altered. Thickening of this oxide layer leads to unstable scanning tunneling ...

1999-02-01

467

Electrocatalytic oxidation of deferiprone and its determination on a carbon nanotube-modified glassy carbon electrode  

Energy Technology Data Exchange (ETDEWEB)

The electrochemical behavior of the anti-thalassemia and anti-HIV replication drug, deferiprone, was investigated on a carbon nanotube-modified glassy carbon (GC-CNT) electrode in phosphate buffer solution, pH 7.40 (PBS). During oxidation of deferiprone, two irreversible anodic peaks, with E{sub 1}{sup 0}=452 and E{sub 2}{sup 0}=906mV, appeared, using GC-CNT. Cyclic voltammetric study indicated that the oxidation process is irreversible and diffusion controlled. The number of exchanged electrons in the electro-oxidation process was obtained, and the data indicated that deferiprone is oxidized via two two-electron steps. The results revealed that carbon nanotube (CNT) promotes the rate of oxidation by increasing the peak current, so that deferiprone is oxidized at lower potentials, which thermodynamically is more favorable. This result was confirmed by impedance measurements. The diffusion coefficient, electron-transfer coefficient and ...

2008-02-15

468

Effect of phlorizin on sugar uptake by broadbean leaf discs. [Vica faba L  

Energy Technology Data Exchange (ETDEWEB)

Phlorizin is a competitive inhibitor of Na/sup +//glucose symport in animal cells and of H/sup +//3-O-methylglucose (3-O-MeG) symport in liverworts. The effects of this compound on the uptake of (U-/sup 14/C) sucrose and of (/sup 14/C) 3-O-MeG by broadbean (Vicia faba L.) leaf discs were studied. Leaf discs without lower epidermis were preincubated in the dark for 30 min (fresh discs) or for 12 h (aged discs) on a medium buffered at pH 5.0 containing mannitol as an osmoticum. They were then incubated for 30 min in the light on a similar solution added with 1 mM (/sup 14/C) sucrose or (/sup 14/C) 3-O-MeG and 5 mM phlorizin. Phlorizin inhibited uptake of 3-O-MeG by 37 and 50% respectively in fresh and aged discs. Sucrose uptake was more sensitive to the inhibitor than 3-O-MeG uptake and was also more inhibited in aged than in fresh discs (76% inhibition vs 54%). Kinetic studies showed that the inhibition exerted by phlorizin in fresh material is of competitive type ...

1986-04-01

469

Ecological risk assessment of the east branch, Finniss River  

International Nuclear Information System (INIS)

Quantitative ecological risk assessment (ERA) is a means whereby the risk posed by a toxicant in any system can be evaluated by comparing the distribution of its measured or modelled concentrations (water quality data (WQD)) with available information on the range of concentrations that are known to adversely affect biota within that, or similar, habitats (dose-response data (DRD)). Initially, the WQD are compared with regulatory criteria (e.g. ANZECC and ARMCANZ, 2000). If they fail this test, then, on the assumption that both data sets comprise subsets of the entire range of concentrations, probability density functions are derived assuming a standard distribution form a typically log-normal. In this paper, AQUARISK has been used to estimate the risk posed by copper in effluent from the Rum Jungle mine site, pre- and post-remediation, and the proportion of taxa likely to be affected in the East Branch (EB) of the Finniss River downstream of the mine. In addition, ...

2002-03-01

470

Direct screening of tetracyclines in water and bovine milk using room temperature phosphorescence detection  

Energy Technology Data Exchange (ETDEWEB)

A fast and simple flow-through optosensor was designed and characterized for the direct screening of four tetracycline (TCC) antibiotics (tetracycline, oxytetracycline, chlortetracycline and doxycycline) in water and bovine milk samples. The proposed optosensor provides rapid binary yes/no overall responses, being appropriate for the screening of this family of antibiotics above or below a pre-set concentration threshold. The experimental set-up is based on a flow-injection manifold coupled on-line to a phosphorescence detector. Aliquots of the samples are pretreated with Eu(III) to form room temperature phosphorescent metal chelates and injected in the flow manifold. Those chelates are then on-line retained on a conventional flow-cell (packed with polymeric Amberlite XAD-4 particles) which is placed inside the cell holder of the phosphorimeter. After the emission is registered, the antibiotic-metal complexes are eluted from the packed resin with 1 M HCl (for milk samples a second ...

2007-04-18

471

Consideration on relationship between radon concentration in soil gas and distribution of hot springs. Radon nodo tokusei to onsen no bunpu tono kankei ni kansuru ichikosatsu  

Energy Technology Data Exchange (ETDEWEB)

This paper describes considerations given on factors affecting radon concentrations, and the radon concentration measurements in hot springs distributed in the northern part of Kumamoto Prefecture. As a result of analyzing radon concentration attenuation in the vertically upward direction using a diffusion equation, it was revealed that radon carrier gas velocities affect strongly the radon concentration, and the [sup 220]Rn source is limited to a very shallow bed below the ground surface. An inclined face was prepared against the [sup 222]Rn decay constant distribution using an inclined face analyzing method. The [sup 222]Rn concentration direction based on this inclined face harmonized approximately well with the hot spring distribution direction. Base rocks that well up hot springs were inferred to be granite from the concentration distribution and pH of chemical components in each hot spring. As a result of surveying joints and linearments ...

1993-02-01

472

All focused ion beam fabricated MgB_2 inter-grain nanobridge dc SQUIDs  

International Nuclear Information System (INIS)

We have fabricated MgB_2 dc SQUIDs (superconducting quantum interference devices) containing inter-grain nanobridges as Josephson elements by a focused ion beam (FIB) etching method and measured their transport properties. The entire structure including the SQUID loop was patterned only using a FIB. The beam energy was 30 kV and the current was 0.9 nA for larger structures and 34 and 1.5 pA for the nanobridge pattern. Each bridge with a nominal width of 100 nm crossed a single grain boundary in the normal direction. The SQUID loop had a 3.1 #mu#m x 3.1 #mu#m hole with a 2 #mu#m average linewidth, corresponding to an inductance of 5.1 pH. The nanobridges had a two-step transition with an increase in the resistivity of more than a decade and a substantial decrease in the critical current density. Current-voltage characteristics showed a resistively shunted junction behavior at all temperatures below T_c, which implies that the current in the ...

2009-06-01

473

2003 Data Report: Groundwater Monitoring Program, Area 5 Radioactive Waste Management Site, Nevada Test Site  

Energy Technology Data Exchange (ETDEWEB)

This report is a compilation of the calendar year 2003 groundwater sampling results from the Area 5 Radioactive Waste Management Site, Nevada Test Site. Wells Ue5PW-1, Ue5PW-2, and Ue5PW-3 were sampled semi-annually for the required analytes: pH, specific conductance, total organic carbon (TOC), total organic halides (TOX), tritium, and major cations/anions. Results from all samples collected in 2003 were within established criteria. These data indicate that there has been no measurable impact to the uppermost aquifer from the Resource Conservation and Recovery Act (RCRA) regulated unit within the Area 5 Radioactive Waste Management Site and confirm that any previous detections of TOC and TOX were false positives. Contamination indicator data are presented in control chart and tabular form with investigation levels indicated. Gross water chemistry data are presented in graphical and tabular form. There were no major changes noted in the ...

2004-02-01

474

Volatilization of fluorides from solid uranium(IV)fluoride  

International Nuclear Information System (INIS)

... deposition evaporation fission products fluorides iodine 134 laboratory

1971-02-01

478

Interstellar PAH Analogs in the Laboratory: Comparison with Astronomical Data  

Science.gov (United States)

Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing

2005-01-01

481

'__-_ _! _/_/ _  

Science.gov (United States)

In 1963, Grover and co-workers at the Los Alamos. Scientific. Laboratory ...... and A. P. Watkins. (1986) "The Computation of Compressible ...

482

 

UK PubMed Central (United Kingdom)

Health surveillance program This article outlines the principal components of quality control of laboratory rodents.

1986-02-01

483

The mechanism of thorium biosorption by Rhizopus arrhizus  

Energy Technology Data Exchange (ETDEWEB)

Inactive cells of Rhizopus arrhizus have been documented to exhibit a high thorium biosorptive uptake (170 mg/g) from aqueous solutions. The mechanism of thorium sequestering by this biomass type was investigated following the same method as for the uranium biosorption emchanism. The thorium sequestering mechanism appeared somewhat different from that of uranium. Experimental evidence is presented which indicates that, at optimum biosorption pH (4), thorium coordinates with the nitroge of the chitin cell wall network and, in addition, more thorium is adsorbed by the external section of the fungal cell wall. At pH 2 the overall thorium uptake is reduced. The kinetic study of thorium biosorption revealed a very rapid rate of uptake. Unlike uranium at optimum solution pH, Fe/sup 2 +/ and Zn/sup 2 +/ did not interfere significantly with the thorium biosorptive uptake capacity of R. arrhizus.

1982-04-01

484

Solubility of Sn(IV) oxide in dilute NaClO{sub 4} solution at ambient temperature  

Energy Technology Data Exchange (ETDEWEB)

The solubility of Sn(IV) oxide was determined in a dilute NaClO{sub 4} solution with pH 2 through 12 at ambient temperature. Both oversaturation and undersaturation experiments were carried out in an inert gas glovebox where the concentration of the oxygen and carbon dioxide were less than 1 ppm. The solubility of Sn(IV) oxide was 3 {times} 10{sup {minus}8} mol/l at neutral pH, and increased at pH > 7.5. Equilibrium constants of soluble reactions were calculated from the experimental data, using curve fitting method. The study suggests that the solubility of Sn(IV) oxide would be higher than that provisionally used in current safety assessments of HLW disposal sites.

1997-12-31

485

Solubility of Sn(IV) oxide in dilute NaClO_4 solution at ambient temperature  

International Nuclear Information System (INIS)

The solubility of Sn(IV) oxide was determined in a dilute NaClO_4 solution with pH 2 through 12 at ambient temperature. Both oversaturation and undersaturation experiments were carried out in an inert gas glovebox where the concentration of the oxygen and carbon dioxide were less than 1 ppm. The solubility of Sn(IV) oxide was 3 x 10"-"8 mol/l at neutral pH, and increased at pH > 7.5. Equilibrium constants of soluble reactions were calculated from the experimental data, using curve fitting method. The study suggests that the solubility of Sn(IV) oxide would be higher than that provisionally used in current safety assessments of HLW disposal sites.

1996-12-02

486

Shear rigidity of spread stearic acid monolayers on water  

Energy Technology Data Exchange (ETDEWEB)

The effect of Al/sup 3 +/, Fe/sup 3 +/, Ca/sup 2 +/, and Mg/sup 2 +/ ions and of pH on the two-dimensional shear modulus of stearic acid spread on a water substrate was determined. A large shear modulus was displayed by the films when the subphase contained Al/sup 3 +/ and Fe/sup 3 +/ ions at the self-buffered pH. With Fe/sup 2 +/ dissolved in the subphase, the film displayed a viscous relaxation when strained but no residual stress was observed. No effect was observed with the Ca/sup 2 +/ or Mg/sup 2 +/. Reducing the pH value in the subphase with the trivalent ions caused the shear modulus to disappear. The observations are interpreted in terms of hydrogen bonding.

1981-09-15

487

Ru/SiO2 AND CuRu/SiO2 PREPARED BY SOL-GEL: EFFECT OF pH AND WATER AMOUNT  

Scientific Electronic Library Online (English)

Abstract in english Ru(1%)/SiO2 and Cu(1%)Ru(1%)/SiO2 catalysts were prepared by cogelation. The effect of pH and the amount of water on the physical-chemical properties and the catalytic properties of them were analyzed. The acid medium increased the formation of microporosity and the formation of small size of metallic ruthenium particle. The variation of the water quantity used in the gelation not modify considerably the texture neither the dispersion of the noble metal. The reduction lev (more) el of all prepared catalyst was similar, showing displacement in some of reduction peaks. The toluene hydrogenation indicated that the conversion and the quantity of hydrogenate product varied with the pH and the quantity of water used in the gelation. The addition of copper to Ru/SiO2 catalysts diminished the reactive conversion and their hydrogenant activity

2003-06-01

488

Polyhydroxyflavones as extractants. Communication 7. Solvent extraction of europrium complexes with morin from alkaline media  

Energy Technology Data Exchange (ETDEWEB)

This paper studies the analytical application of europium (III)-morin complex which is formed in alkaline medium and has an intense color. The extent of europium extraction was determined by adding to the extract a morin solution in isoamyl alcohol in a 50-100-fold excess with respect to europium. The dependence of the optical density of the extracts on the ph in the system europium (III)-morin-water-organic solvent for different excesses of the reagent is shown: this indicates formation of two extractable complexes, one being dominant in the pH range 4-7, the other at pH greater than or equal to 8.5. The extraction of the europium (III)-morin complex from alkaline solution is used for direct extraction-photometric determination of europium(III) in compounds of elements having amphoteric properties or forming amines (Zns, Mo0/sub 3/).

1985-09-01

489

Optimization of band gap of photonic crystals fabricated by holographic lithography  

Science.gov (United States)

Generally the photonic band gap (PBG) is a multi-variable function of several parameters related to the shape and size of the dielectric columns of photonic crystals (PhCs), and a time-consuming step-by-step scanning process for each parameter has to be used to find their best combination yielding maximum PBG. In this letter, the widely used Nelder-Mead simplex algorithm is introduced to optimize these parameters simultaneously to find a larger PBG for a new kind of two-dimensional (2D) hexagonal GaAs-Air PhC. This structure can be conveniently produced by the single-exposure holographic lithography, and the specific holographic design is also systematically investigated. This study reveals that the band gaps of PhCs made by holographic lithography may be widened by introducing irregularity of the columns and lowering the symmetry of the structure.

2008-01-01

490

Optimisation of pectin acid extraction from passion fruit peel (Passiflora edulis flavicarpa) using response surface methodology  

British Library Electronic Table of Contents (United Kingdom)

Summary Pectin was extracted from passion fruit peel using three different acids (citric, hydrochloric or nitric) at different temperatures (40-90 degreeC), pH (1.2-2.6) and extraction times (10-90 min), with and without skins using a 24 factorial design. Temperature, pH and extraction time had highly significant effects on the pectin yield. A central composite design with face centring was used to optimise the extraction process conditions for citric acid without skins. Pectin yields varied from 10% to 70%. The optimal conditions for maximisation of pectin yield were the use of citric acid at 80 degreeC and pH 1 with an extraction time of 10 min considering model extrapolation.

2009-01-01

491

On the interaction of vanadium (4) with derivatives 3,4,5-trihydroxy-isoxanthene  

International Nuclear Information System (INIS)

A study was made on interaction of vanadium (4) ions with dyes-pyrogallol red, brompyrogallol red and gallein- in the range of pH = 0-6. The maximal light absorption for gallein and brompyrogallol red is observed at pH=4 and #lambda#max = 545 nm and 560 nm respectively. The compound of vanadium (4) with pyrogalloe red is characterized by the maximal light absorption at pH=5 and #lambda#max=560 nm. Component ratio in all analyzed compounds is equal to 1:2. Molar extinction coefficients for compounds with gallein, pyrogallol red and brompyrogallol red are equal to 5000, 550 and 7400, and logarithms of stability constants - to 9.27, 13.17 and 13.25 respectively.

492

Lead, copper and zinc biosorption from bicomponent systems modelled by empirical Freundlich isotherm  

Energy Technology Data Exchange (ETDEWEB)

The biosorption of lead, copper and zinc ions on Rhizopus arrhizus has been studied for three single-component and two binary systems. The equilibrium data have been analysed using the Freundlich adsorption model. The characteristic parameters for the Freundlich adsorption model have been determined and the competition coefficients for the competitive biosorption of Pb(II)-Cu(II) at pH 4.0 and 5.0, and Pb(II)-Zn(II) at pH 5.0 have been calcualted. For the individual single-component isotherms, lead has the highest biosorption capacity followed by copper, then zinc. The capacity of lead in the two binary systems is always significantly greater than those of the other metal ions, in agreement with the single-component data. Only a partial selectivity for copper ions has been obtained at pH 4.0. (orig.)

2000-07-01

493

Hydrogen-atom attack on methyl viologen in aqueous solution studied by pulse radiolysis  

International Nuclear Information System (INIS)

Using hydrogen at high pressures of up to 150 bar as an OH scavenger in aqueous MV"2"+ solutions (pH 1) it is possible to differentiate between two kinds of transient formed simultaneously by H-atom attack on methyl viologen. One of them is assigned to an H adduct on the N atom, MV"+H"+, with absorption bands identical to those of the radical cation, MV"+. The MV"+H"+ species deprotonates forming the long-lived radical cation, MV"+. The second type of transient produced is attributed to an H-adduct on the ring carbon, MV"2"+H, decaying by second-order kinetics. The formation of MV"+ by electron transfer from the propan-2-ol radical has been reinvestigated (pH 0 to 7); its absorption spectrum does not change in this pH range. Rate constants and molar extinction coefficients are presented. (U.K.).

1984-01-01

494

Extraction of rare earths by carbonic acids melts  

Energy Technology Data Exchange (ETDEWEB)

Extraction of rare earths (La, Ce, Pr, Eu, Gd, Er, Yb) from nitrate solutions by melts of carboxylic acids of the C/sub 17/-C/sub 20/ fraction and stearic acid with paraffin, depending on the temperature (60-90 deg), phase contact time and their volume ratio (O:B from 1:5 up to 1:100), pH of the aqueous phase (2-6), rare earth concentration (10/sup -6/-10/sup -3/ m) is studied. It is shown that in the whole concentration range investigated rare earths are extracted quantitatively into the carboxylic acid melt of C/sub 17/-C/sub 20/ fraction at the equilibrium value of pH>=3.8, while into the melt of 0.1 M stearic acid in paraffin at pH>=4.5.

1980-10-01

495

Biosorption of uranium (VI) by immobilized Aspergillus fumigatus beads  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of uranium (VI) ions by immobilized Aspergillus fumigatus beads was investigated in a batch system. The influences of solution pH, biosorbent dose, U (VI) concentration, and contact time on U (VI) biosorption were studied. The results indicated that the adsorption capacity was strongly affected by the solution pH, the biosorbent dose and initial U (VI) concentration. Optimum biosorption was observed at pH 5.0, biosrobent dose (w/v) 2.5%, initial U (VI) concentration 60 mg L{sup -1}. Biosorption equilibrium was established in 120 min. The adsorption process conformed to the Freunlich and Temkin isothermal adsorption models. The dynamic adsorption model conformed to pseudo-second order model.

2010-06-15

496

Abundance response of western European forest species along canopy openness and soil pH gradients  

British Library Electronic Table of Contents (United Kingdom)

In order to better understand the structure and composition of forest plant communities, we aimed to predict the abundance of understory herbaceous species locally at the stand level and according to different environments. For this, we seeked to model species distributions of abundance at a regional scale in relationship with the local stand structure (canopy openness) and regional soil resources (soil pH). Floristic inventories, performed in different light and soil conditions located in 1202 records of north eastern France, were used to analyze the combined effect of canopy openness and soil pH on the abundance of 12 common western European forest species: Anemone nemorosa, Deschampsia flexuosa, Festuca altissima, Hedera helix, Lamium galeobdolon, Lonicera periclymenum, Molinia caerulea...

2011-01-01

497

Radon gas monitoring survey for the determination of Radon Prone Areas in Lombardia  

Energy Technology Data Exchange (ETDEWEB)

Region Lombardia has carried out a radon gas monitoring survey on its territory to localize radon prone areas as by law 241/00 enacted. To plan the survey, the Lombardia territory has been divided into two different types according to the morphology as well as the presence of a substratum of rock. The area with hills and mountains has been investigated with more attention compared to the plain because we can assume higher variability in radon concentration distribution due to the geological and morphological characteristics. The territory subdivision was based on the standard grid.. of the techniregional cartography (8 x 5 km). To perform radon indoor concentration measurements about 3600 measuring points were selected. They are located at the ground floor of buildings with the characteristics to ensure the tests are representative and comparable. It has also been taken into account evaluations done with previous surveys in accordance with the ...

2006-07-01