International Nuclear Information System (INIS)

... 45 p. absorption spectroscopy errors lead lead 203 beta decay radioisotopes

Energy Technology Data Exchange (ETDEWEB)

The motivation of this work is to develop high reflectance normal-incidence multilayer mirrors in the 8-12 nm wavelength region for applications in astronomy and extreme ultraviolet lithography. To achieve this goal, Mo/Sr and Mo/Y multilayers were studied. These multilayers were deposited with a UHV magnetron sputtering system and their reflectances were measured with synchrotron radiation. High normal-incidence reflectances of 23% at 8.8 nm, 40.8% at 9.4 nm, and 48.3% at 10.5 nm were achieved. However, the reflectance of Mo/Sr multilayers decreased rapidly after exposure to air. Attempts to use thin layers of carbon to passivate the surface of Mo/Sr multilayers were unsuccessful. Experimental results on the refractive index {tilde n} = 1-{delta} + i{beta} of yttrium and molybdenum in the 50-1300 eV energy region are reported in this work. This is the first time ever that values on the refractive index of yttrium are measured in this energy range. The absorption ...

International Nuclear Information System (INIS)

Cisplatin (cis-diaminedichloroplatinum [II] is a coordination compound, used in the treatment of several solid tumors. Cisplatin and its hydrolysis products exhibit a great pharmacological effect but are very toxic and probably carcinogenic. The present review summarizes the most important advances in the last years in the techniques employed for the detection and quantification of cisplatin and its hydrolysis products and in the different matrixes studied. The new emerging techniques and their modifications recently developed, fundamentally the combined use of detection and separation techniques for the analysis of platinum species and their impact on the speed, sensitivity and specificity of the analytical determination, with regard to the techniques used in the last century are discussed. High-Performance Liquid Chromatography and Capillary Electrophoresis, coupled with detection methods such as Mass Spectrometry, Inductively Coupled Plasma-Mass ...

International Nuclear Information System (INIS)

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

British Library Electronic Table of Contents (United Kingdom)

Microanalytical methods suitable for the determination of Fe, Cu in HT-29 (human colon adenocarcinoma) cells treated with different iron compounds (Fe(II) sulfate, Fe(III) chloride, Fe(III) citrate and Fe(III) transferrin) and cultured in medium supplemented or not with 10% (v/v) fetal calf serum (FCS) by total reflection X-ray fluorescence spectrometry (TXRF) and simultaneous graphite furnace atomic absorption spectrometry (GF-AAS) were developed. The developed TXRF method was also suitable for Zn determination in the samples. The main advantage of the proposed methods is the execution of all sample preparation steps following incubation and prior to the elemental analysis in the same Eppendorf tubes. Sample preparation was performed at microscale (115mL sample volume) with 65% nitric aci...

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A water trap system based on a thermoelectric cooling device is employed to remove a major fraction of the water from air samples, prior to analysis of these samples for chemical composition, by a variety of analytical techniques where water vapor interferes with the measurement process. These analytical techniques include infrared spectroscopy, mass spectrometry, ion mobility spectrometry and gas chromatography. The thermoelectric system for trapping water present in air samples can substantially improve detection sensitivity in these analytical techniques when it is necessary to measure trace analytes with concentrations in the ppm (parts per million) or ppb (parts per billion) partial pressure range. The thermoelectric trap design is compact and amenable to use in a portable gas monitoring instrumentation.

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Research highlights: {yields} The polarization curve of 316L SS possesses five turning potentials in passive region. {yields} Films formed at turning potentials perform different electrochemical and semiconductor properties. {yields} Dissolutions and regenerations of passive film at turning potentials are obtained by AAS and XPS. {yields} Turning potentials appearing in passive region are ascribed to the changes of the compositions of the passive films. - Abstract: The passivity of 316L stainless steel in borate buffer solution has been investigated by Mott-Schottky, atomic absorption spectrometry (AAS) and X-ray photoelectron spectroscopy (XPS). The results indicate that the polarization curve in the passive region possesses several turning potentials (0 V{sub SCE}, 0.2 V{sub SCE}, 0.4 V{sub SCE}, 0.6 V{sub SCE} and 0.85 V{sub SCE}). The passive films formed at turning potentials perform different electrochemical and semiconductor properties. ...

International Nuclear Information System (INIS)

In this work, a water-soluble polymer, polyethylenimine (PEI) was used for the simultaneous separation and preconcentration of trace Cu and Mn prior to their determination by flame atomic absorption spectrometry. For this purpose, the sample and the PEI solution were mixed and the metal-bound polymer was precipitated by adding acetone. The precipitate was separated and dissolved in a minimum amounts of water and aspirated into a flame AAS. By increasing the ratio of the volumes of sample to water used in dissolving the precipitate, the analyte elements were concentrated as needed. The sorption is quantitative in the pH ?6. Detection limits were 5.2 ?g/L for Cu and 5.4 ?g/L for Mn. This method is simple, fast and precise.

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A new method for the separation and determination of trace amounts of cadmium and zinc in water as their thenoyltrifluoroacetone (TTA) complexes with dibenzo-18-crown-6 (DB18C6) in o-dichlorobenzene has been established by means of synergistic extraction and back-extraction combined with atomic absorption spectrometry. The effect of various factors (synergism with TTA and DB18C6, shaking time, composition of the extracted species, and mutual separation etc.) on the extraction and back-extraction of cadmium and zinc has been in- vestigated. When the mixtures were extracted for 4 min at pH 4.9, only zinc was extracted quantitatively, whereas cadmium remained in the aqueous phase. After the phases were separated, cadmium was again extracted quantitatively at pH 7.5. Then, the two phases were each shaken with 0.05-0.1 mol/l HCl in order to back-extract cadmium and zinc from the organic phases; the ions were determined individually by atomic ...

CERN Document Server

A Bragg curve ionization chamber for acceleration mass spectrometry

International Nuclear Information System (INIS)

The paper contains a numerical evaluation of the expressions for the absorptive potential in heavy ion reactions given earlier. With a standard folding expression for the real part of the ion-ion potential general good agreement is found with experimental data for the angular distributions of elastic and inelastic scattering. Special interest is attached to the case of "1"6O + "2"8Si where the calculated imaginary potential is very small at low bombarding energies. (orig.).

International Nuclear Information System (INIS)

This article reviews the principal evidences about aluminum neurotoxicity in vitro, and some evidences in brain tissues of Alzheimer patients; and also show some studies realized with human that suffer renal deficiencies, dealing whit the principal osteodystrophy. The problem of analyzing low aluminum concentration in human fluids is overcome with very sensitive analytical methods as electrothermal atomic absorption spectrometry (ETAS) and voltammetric methods as Anodic Striping Voltammetry with complexing agents that easing adsorption over solid electrodes or mercury hanging drops. Is a vital question to know with accuracy the aluminum concentration in water used in hemodialysis or in fluids used in ambulatory peritoneal dialysis, as a first stage to prevent contamination by aluminum. So the prevention of contamination during sapling storage and analysis of biological fluids should be the first need and the sources of water used in renal ...

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Mass and charge distributions of products from fission of sup(242m)Am induced by thermal neutrons have been investigated by means of the semiconductor spectrometry of ..gamma.. radiation from a mixture of non-separated fragment nuclei. Specimens of the fissible material have been irradiated in the vertical experimental channel of the research reactor then the measurements have been performed with calibrated semiconductor detectors. Three experiments with substantially different irradiation times have been performed to expand the nomenclature of the investigated fission products. The spectra of ..gamma.. radiation from the mixture of fission products, and time dependences of the counting rates at the total absorption peaks have been handled with computers. The obtained yields are compared with data of previous investigations performed with different experimental methods, as well as with the calculated one.

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Ba, Cd, Cr, Cu, Fe, Ni, Pb and Zn were determined in birch leaves (Folium Betulae), dandelion roots (Radix Taraxacae), hawthorn blossom (Inflorescentia Crataegi) and their infusions by graphite furnace atomic absorption spectrometry (GFAAS) after microwave digestion of plant samples. Infusions were made from herbs according to prescription for patients, provided by the producer of medicine on the package. The results obtained were compared with daily requirements for each element. Results show high content of cadmium in the medicinal plants analyzed. The highest level in infusions was observed for Ni and Zn (over 90% of the total element concentration for Ni and in most cases over 50% for Zn), and the lowest for Cd and Pb. The calculated daily intake of majority of the analyzed elements was very low (under 1% of daily requirements)

International Nuclear Information System (INIS)

The activities of the radiochemical section (part of the Analytical Chemistry Group) deal mostly with problems of composition. Activation analysis with thermal neutrons serves for most of the trace element analyses either with or without chemical separations. Ge(Li) spectrometry has been increasingly automated so that many analyses can now be performed by relatively unskilled personnel. In a number of analyses an A.V.F.-cyclotron was employed: such an accelerator can deliver not only different types of charged particles at variable energies but also fast neutrons. (T.G.).

Science.gov (United States)

No Abstract Available

International Nuclear Information System (INIS)

The method of augmented plane wave (APW) is used to obtain the band structure of the SmS compound in the semiconductor and metal phases. The noncentral part of the Coulomb electron-electron interaction is taken into account in the first order perturbation theory. In this case the radial part of the wave APW-function is taken as a zero approximation function. A multiplet structure of the excited configuration f"5d, which provides a good description of the X-ray photoelectron spectrum and optical spectrum epsilon_2(#omega#), is obtained. The configuration fd is calculated for the interpretation of the optical absorption spectrum of the samarium monosulfide metal phase. (author).

Energy Technology Data Exchange (ETDEWEB)

The Monte Carlo simulation method is applied to calculate the nucleon transfer part of the imaginary optical-model potential in colliding heavy ions. In the process of transfer of nucleons from one nucleus to the other, forward and backward neutrons and protons are treated separately by taking into consideration the effect of the Coulomb forces and the potential energy surfaces (driving forces). The Pauli exclusion principle is also incorporated properly in the calculation.

Energy Technology Data Exchange (ETDEWEB)

Recently there has been much concern with the ability of plants to uptake heavy metals from their surroundings. With the development of instrumental techniques with low detection limits such as inductively coupled plasma-mass spectrometry (ICP-MS), attention is shifting toward achieving faster and more elegant ways of oxidizing the organic material inherent in environmental samples. Closed-vessel microwave dissolution was compared with conventional methods for the determination of concentrations of cerium, samarium, europium, terbium, uranium and thorium in a series of samples from the National Institute of Standards and Technology and from fields in Idaho. The ICP-MS technique exhibited detection limits in parts-per-trillion and linear calibration plots over three orders of magnitude for the elements under study. The results obtained by using nitric acid and hydrogen peroxide in a microwave digestion system for the analysis of reference ...

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An investigation was made of the accumulation of laser damage to transparent polymers irradiated with nanosecond pulses from neodymium and ruby lasers. The damage was investigated by the method of scattering and luminescence in the visible and near ultraviolet parts of the spectrum. It was established that there were two stages in laser damage by repeated irradiation with pulses of intensity below the single-shot damage threshold. An absorbing defect evolved during the first stage in such a way as to create a thermal instability in the surrounding matrix. During the second stage this thermal instability caused spatial growth of laser damage because of propagation of an ionization-inducing absorption wave with a front traveling at the rate governed by the electron component of the thermal conductivity.

British Library Electronic Table of Contents (United Kingdom)

Abstract Four stratigraphic sections in the southern part of the Columbia Basin preserve a sequence of aeolian and non-aeolian sediments ranging in age from 943 to >470 14C ka based on accelerator mass spectrometry radiocarbon dating of fossil molluscs, geochemistry of Cascade Mountain-sourced tephra and association with formally recognized pedostratigraphic units (the Washtucna and Old Maid Coulee soils). Study sections are interpreted as representing concurrent deposition of loess and distal Missoula Flood rhythmites in valleys tributary to main drainages backflooded during the Missoula Floods, and formation of carbonate and iron-rich soils. Sediments belong to the formally recognized L-1 and L-2 loess units established for the Palouse loess, which were deposited in the Columbia Basin su...

International Nuclear Information System (INIS)

We report synthesis, characterization and ion transport in polyether-based ionic melt electrolytes consisting of Li salts of low-basicity anions covalently attached to polyether oligomers. Purity of the materials was investigated by HPLC analysis and electrospray ionization mass spectrometry. The highest ionic conductivity of 7.1 x 10-6 S/cm at 30 deg. C was obtained for the sample consisting of a lithium salt of an arylfluorosulfonimide anion attached to a polyether oligomer with an ethyleneoxide (EO) to lithium ratio of 12. The conductivity order of various ionic melts having different polyether chain lengths suggests that at higher EO:Li ratios the conductivity of the electrolytes at room temperature is determined in part by the amount of crystallization of the polyether portion of the ionic melt.

Energy Technology Data Exchange (ETDEWEB)

Specific parts of several plants (fruits, leaves, stem, bark and roots) often used as medicines in the Indian Ayurvedic system have been analysed for 20 elements (As, Ba, Br, Ca, Cl, Co, Cr, Cu, Fe, K, Mn, Mo, Na, P, Rb, Sb, Sc, Se, Sr and Zn) by employing instrumental neutron activation analysis (INAA). The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted using high resolution gamma ray spectrometry. Most of the medicinal herbs have been found to be rich in one or more of the elements under study. (Author).

Energy Technology Data Exchange (ETDEWEB)

Ultratrace analysis of mercury in rain water has been investigated, including recovery of ionic mercury with the addition of acids, treatment and storage and stability studies of mercury in rain water. Recovery of ionic mercury from rain water samples increased with increased acid concentrations and increased substantially with UV-irradiation. Recovery of ionic mercury in the presence of different acids was compared. Treatment studies of rain water for the analysis of total mercury were done using different decomposition methods. More than 20% of the total mercury was found in rain water residue after filtration through 0.45 ..mu..m membrane filters. Methylmercury (MM) content in filtered and unfiltered rain water however was nearly the same. On long term storage of rain water without acids at pH = 2.0 and 4.5 loss of total mercury occurred, but in the presence of acids increasing amounts of ionic mercury were recovered from rain water samples with increasing storage time. Naturally ...

International Nuclear Information System (INIS)

An x-ray fluorescence spectrometer was designed and fabricated which nondestructively determines the thickness of aluminum cladding at small suspected thin spots in the inner or outer surface of actinide reactor tubes. The analysis method is based on the difference in absorption of actinide L/sub #alpha#/ and L/sub #beta#/ fluorescent x-rays in passing through the cladding. Calibration plots of the logarithm of the L/sub #beta#//L/sub #alpha#/ x-ray intensity ratio versus cladding thickness are linear to at least 40 mils for U-Al, U_3O_8-Al, and PuO_2-Al substrates. Accuracy and precision of the experimentally determined cladding thickness and evaluated for both uranium and plutonium substrates. Experimental thickness data are reported for 618 quality assurance analyses on six Mark 41 PuO_2-Al target tubes. An x-ray fluorescence cladding thickness monitor operated with a computer-controlled fluoroscope holds considerable promise for quality assurance because (1) a ...

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The further development of a Guideline (formerly Protocol) for sampling and analysis of 'tars' from biomass producer gases is reported. This Guideline is being developed as a project within the European Fifth Framework Programme with additional partners from Switzerland and North-America. In this paper an outline and the principle of the Guideline are given. The Guideline is based on isokinetic sampling of particles and 'tar' from the main producer gas duct, particle filtration at high temperature, gas cooling in a liquid quench, 'tar' absorption in a solvent at low temperatures, an optional backup adsorber, and flow measurement and control. The Guideline gives a definition for 'Gravimetric tar' which is the 'tar' number to be determined by the Guideline. Also, the Guideline gives procedures for compound analysis by gas chromatography - mass spectrometry ...

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The optoelectronic compounds of GaAs and ZnSe are difficult to analyze by PIXE (particle-induced X-ray emission) due to the strong absorption of the As and Se K{sub {alpha}} X-rays. As part of a program to investigate optoelectronic materials using ion beam techniques, we have explored the possibility of using the high sensitivity of PIXE to check these materials for stoichiometry and dopant concentrations. The K{sub {alpha}} X-ray intensity ratios of Ga to As and Zn to Se have been investigated using H beams of 0.5 to 2.5 MeV and He beams of 1.0 to 2.5 MeV. The variation in the X-ray intensity ratio with beam energy and target thickness is modelled in terms of the cross section for X-ray production and the absorption coefficients of the X-rays in the target. The results of this model show the experimental conditions that must be satisfied in order that the X-ray intensity ratios are not strongly affected by X-ray ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes the design, operation, and performance of an HVAC system installed as part of a project to demonstrate energy efficiency and environmental responsibility in commercial buildings. The systems installed in the 2180 m{sup 2} office building provide superior air quality and thermal comfort while requiring only half the electrical energy of conventional systems primarily because of the hydronic heating and cooling system. Gas use for the building is higher than expected because of longer operating hours and poor performance of the boiler/absorption chiller.

British Library Electronic Table of Contents (United Kingdom)

A novel difunctional acylhydrazone has been synthesized by the reaction of 5-methylisoxazole-4-carboyl hydrazine with benzaldehyde and characterized by X-ray crystallography and spectroscopy. The obtained results demonstrate the crystal belongs to triclinic, space group Formula Not Shown . Moreover, the spectroscopic properties were evaluated through density functional theory (DFT) and time-dependent density functional theory (TD DFT) calculations. The results reveal that UV-Vis absorption peaks at 194, 217.5 and 290.5nm are mainly attributed to (p, p)p*, partly (p, p)p* and partly pp*, and predominantly pp*, respectively, with intraligand charge-transfer transition (ILCT) character. The fluorescence emission peak at 485.96nm should be assigned to ILCT. In addition, the results of antibact...

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The deuterium uptake behavior of Zr-2.5Nb pressure tubes in Wolsung Unit 1 was analyzed in terms of longitudinal location, operation time, and coolant temperature. The results were compared with those obtained from Canadian CANDU reactors. The amount of deuterium uptake was higher at the outlet part than at the inlet part and was also higher when subjected to a longer operation time and a higher coolant temperature. The hydrogen uptake of Zr-2.5Nb in a hydrogen gas atmosphere was dependent on the microstructure of the alloy. The aged Zr-2.5Nb consisting of {alpha}-Zr and {beta}-Zr phases. The hydrogen in the alloy decreased the rate of oxidation. This could be explained in terms of the cathodic controlled reaction of Zr-2.5Nb oxidation. (author)

International Nuclear Information System (INIS)

A method for enrichment of the ppb level of cadmium in water by using the coagulation of soybean protein by adding acids or its complex-forming character with heavy metal ions was investigated. After adding fixed amounts of soybean milk and 2% sodium diethyldithiocarbamate(DDTC) aqueous solution and a suitable amount of delta-gluconic lactone (delta-GL) to a sample solution, the mixture was heated to boiling in order to coagulate the protein. The coagulum(soybean curd) was separated from the suspension by centrifugation and burned to ashes with a low temperature plasma asher. Then the cadmium enriched in it was determined by atomic absorption spectrometry. Various factors such as the pH of the sample solution, the amounts of soybean milk and the collection additives, and the concentration of NaCl in the sample solution on the recovery of cadmium were examined systematically. The best recovery was obtained under the following conditions: To a ...

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Current applications of ..cap alpha..-particle spectrometry in post-irradiation research and reprocessing are reviewed. Implementation of procedures and techniques described in the literature to the particular samples at S.C.K./C.E.N. often results in a combined radiochemical method where ..cap alpha..-particle spectrometry is used to complement or enforce results obtained by other methods. Typical cases are reported and results obtained by different methods are compared to the results obtained by ..cap alpha..-particle spectrometry.

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The retina consists of many kinds of central nervous cells, and some cells contain fatty acids such as palmitic acid, stearic acid and oleic acid. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) has a possibility to detect kinds and quantity of materials in relation to the cell or tissue. We applied TOF-SIMS to detect the palmitic acid, stearic acid and oleic acid in the visual cell of the rat retina. We used 4- and 18-month-old normal Wistar Kyoto rats. After pentobarbital anesthesia, the eyes were enucleated, and immediately put into liquid nitrogen without any fixation and then cut into semithin sections (10 {mu}m) with a cryo-ultramicrotome, and laid it on a silicon wafer plate and air-dried. Ion images were detected with TOF-SIMS. Positive ion images were examined with a Ga{sup +} source at an acceleration voltage of 15 keV. The secondary ion acceleration voltage was 4.5 keV. In the 4-month-old rat, palmitic and stearic acid were detected in the ...

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 ...

International Nuclear Information System (INIS)

... biological effects body burden diet intestinal absorption lead lead 203 man

Energy Technology Data Exchange (ETDEWEB)

The most important kaolin deposits from Campo Alegre region (S C) were formed by the conjunction of at least one hydrothermal phase followed by many others weathering, supergenic, phases. Possibly deposits formed by only one of these processes exist, but these deposits shall be small and smaller than those mined today. Besides kaolinization, illitization/muscovitization and silicification, hydrothermalism also generated pyritized and propilitized zones, with quartz + chlorite. Together, hipogenic alterations related to kaolin deposits are very similar to alterations of high sulfidation epigenetic volcanogenic gold deposits. Most part of the biggest kaolin mines from the southern part of Campo Alegre Basin are distributed along a 13 Km long and 0,5 Km width bent zone that is parallel to structural alignments that point out the eastern Basin border. This zone was originated by deformation that has inclined and broken rocks, generating a fault ...

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The gastrointestinal absorption of lead was markedly increased in human subjects who had fasted before ingesting lead. Food in the gut was found to reduce lead absorption, and the effect of dietary constituents on /sup 203/Pb absorption was investigated. The greatest reduction in absorption was caused by minerals. This dependence of lead absorption on dietary constituents complicates the establishment of safe levels of lead in food and water.

British Library Electronic Table of Contents (United Kingdom)

In this study, wood samples were exposed to light irradiations (direct sunlight, xenon lamp, mercury vapour lamp) and thermal treatments were carried out in dry- and in humid conditions at 90degreeC. One part of the samples was covered by an aluminium plate during light irradiation. The samples under the aluminium plate also suffered considerable chemical changes, monitored by infrared technique and colour measurement. The sunlight produced greater colour change under the aluminium plate than the artificial light sources. During light irradiation, the carbonyl band having two maximum at 1700 and 1746cm-1 increased and the peak of the aromatic skeletal vibration arising from lignin (1510cm-1) decreased together with the guaiacyl vibrations at 1275cm-1. There was absorption decrease at 1174c...

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The concentrations of iron, chromium, zinc, and aluminum were measured by atomic absorption spectroscopy in the lipid-soluble fractions of tar from the process stream of an experimental coal gasifier as part of large study on the health risks of coal gasification. Lipid solubility was inferred from octanol/water-partitioning and benzene-solubility tests. The properties of the lipid-soluble metals were compared to reference compounds by Sephadex LH-20 chromatography. The ability of the lipid-soluble metals to remain lipid soluble after treatment with acid and base was also tested. Lipid-soluble iron, chromium, zinc, and aluminum were present at 360, 12, 3, and 1 ppM, respectively, in the gasifier coal tar. The presence of these metals in lipid-soluble form may have important consequences relative to the potential toxicity of the tar if persons are exposed to it.

UK PubMed Central (United Kingdom)

We have developed a method for dissecting single neurons from the nematode Ascaris suum, in order to determine their peptide content by mass spectrometry (MS). In this paper,...Full Text Available

UK PubMed Central (United Kingdom)

Charge reduction electrospray mass spectrometry (CREMS) reduces the charge states of electrospray-generated ions, which concentrates the ions from a protein into fewer peaks spread over a larger...Full Text Available

International Nuclear Information System (INIS)

... coincidence spectrometry decay excited states gamma spectra half-life

International Nuclear Information System (INIS)

... correlation beta-minus decay coincidence spectrometry experimental data

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 of the ruthenium concentration is not in agreement with the ...

International Nuclear Information System (INIS)

The effects of different exposure concentrations of palladium (Pd) on relative metallothionein (MT) response and bioaccumulation were investigated in zebra mussels (Dreissena polymorpha). The mussels were exposed to 0.05, 5, 50, and 500 ?g/L Pd2+ for 10 weeks under controlled temperature and fasting conditions. Relative MT contents were assessed by a modified Ag-saturation method, which allows to discriminate between MT bound to Pd (Pd-MT) and MT bound to unidentified metals (Ag-MT). Determination of metal contents resulted from atomic absorption spectrometry following a microwave digestion. For unexposed mussels and mussels exposed to 0.05 ?g/L Pd no metal accumulation could be detected. All other exposure concentrations resulted in detectable Pd accumulation in mussels with final tissue concentrations of 96 ?g/g (500 ?g/L), 45 ?g/g (50 ?g/L), and 9 ?g/g (5 ?g/L). Compared with initial levels Pd-MT concentrations at the end of the exposure ...

International Nuclear Information System (INIS)

FexZn1-x alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K?/K? x-ray intensity ratios of Zn and Fe in FexZn1-x thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi 241Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in FexZn1-x thin films for different values of x. The reason for this change may be that the electronegativity of iron is ...

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Bremstrahlung Isochromat Spectroscopy (BIS). The XES spectra were collected using a Specs electron gun for the excitation and the XES 350 grating monochromator and channel plate system from Scienta as the photon detection. Spectra were collected in 'normal mode,' where the electron gun kinetic energy (KE) and the energy position of the center of the channel plate were both fixed and the energy distribution in the photon (hv) spectrum was derived from the intensities distributed across the channel plate detector in the energy dispersal direction. The polycrystalline Ce sample was oxidized by exposure to air at ambient pressures. After introduction to the ultra-high vacuum system, the oxidized sample was bombarded with Ar, to clean the topmost surface region and stabilize the surface and near surface regions. Although CeO{sub 2} would be the thermodynamically preferred composition in an oxygen rich environment, the combination of a vacuum environment and ion etching may ...

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The influence of a decarburisation process during austenitising of the through-hardenable rolling bearing steel 100Cr6 (SAE 52100) on the rim zone properties of the martensitic through-hardened material was investigated by means of material analysis and diffusion calculations. For this purpose, two specimens were prepared under defined heat treatment conditions, and the near-surface carbon distribution was determined micro-chemically by using secondary ion mass spectrometry (SIMS). In part 1 of the present work, these concentration profiles are compared with the depth variation of the micro-hardness and with the distance curves of the residual stresses and the line broadening ({l_brace}211{r_brace} {alpha}'-Fe diffraction line) both measured by X-ray diffraction (XRD). In addition, microstructure investigations were performed. In part 2, a refined kinetics model of a diffusion-controlled reaction based on the ...

UK PubMed Central (United Kingdom)

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

International Nuclear Information System (INIS)

The possibility of gamma-absorption identification of the analyzed substance is considered. the basic provisions of the proposed method are concentrated on the example of carbohydrates and hydrocarbons. The above method is tested experimentally on polyethylenes and polystyrene

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 fluorescence and absorbance. Isotopically selective excitation of uranium vapor also was the basis of the ...

Energy Technology Data Exchange (ETDEWEB)

In this work, we use lasers to enhance possibilities of laser desorption methods and to optimize coating procedure for capillary electrophoresis (CE). We use several different instrumental arrangements to characterize matrix-assisted laser desorption (MALD) at atmospheric pressure and in vacuum. In imaging mode, 488-nm argon-ion laser beam is deflected by two acousto-optic deflectors to scan plumes desorbed at atmospheric pressure via absorption. All absorbing species, including neutral molecules, are monitored. Interesting features, e.g. differences between the initial plume and subsequent plumes desorbed from the same spot, or the formation of two plumes from one laser shot are observed. Total plume absorbance can be correlated with the acoustic signal generated by the desorption event. A model equation for the plume velocity as a function of time is proposed. Alternatively, the use of a static laser beam for observation enables reliable determination of plume ...

International Nuclear Information System (INIS)

The paper is Part 2 of the study on the thermodynamic and thermoeconomic analyses of trigeneration system with a gas-diesel engine. In Part 1, thermodynamic and thermoeconomic methodologies for such a comprehensive analysis were provided, while this paper applies the developed methodology to an actual TRIGEN system with a rated output of 6.5 MW gas-diesel engine installed in the Eskisehir Industry Estate Zone, Turkey. Energy and exergy efficiencies, equivalent electrical efficiency, the Public Utility Regulatory Policies Act (PURPA) efficiency, fuel energy saving ratio, fuel exergy saving ratio and other thermodynamic performance parameters are determined for the TRIGEN system. The efficiencies of energy, exergy, PURPA and equivalent electrical efficiency of the entire system are found to be 58.97%, 36.13%, 45.7% and 48.53%, respectively. For the whole system and its components, exergetic cost allocations and various exergoeconomic performance ...

KoreaScience (Korea)

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International Nuclear Information System (INIS)

We have estimated the mixing height (MH) and investigated the relationship between vertical mixing and ground-level ozone concentrations in Seoul, Korea, by using three ground-based active remote sensing instruments operating side by side: micro-pulse lidar (MPL), differential absorption lidar (DIAL), and differential optical absorption spectroscopy (DOAS). The M H is estimated from MPL measurements of aerosol extinction profiles by the gradient method under convective conditions. Comparisons of the MHs estimated from MPL and radiosonde measurements show a good agreement (r"2 = 0.99). Continuous MPL measurements with high temporal and vertical resolution reveal the diurnal variations of the MH under convective conditions and the presence of a residual layer during the nighttime. Comprehensive measurements of ozone and aerosol by MPL, DIAL and DOAS during an high ozone episode (24-26 May 2000) in Seoul, Korea, reveal that (1) photochemical ozone ...

Energy Technology Data Exchange (ETDEWEB)

During the last 15 years cycles with CO{sub 2} capture have been in focus, due to the growing concern over our climate. Often, a natural gas fired combined cycle with a chemical absorption plant for CO{sub 2} capture from the flue gases have been used as a reference in comparisons between cycles. Neither the integration of the steam production for regeneration of amines in the combined cycle nor the off-design behaviour of such a plant has been extensively studied before. In this paper, the integration of steam production for regeneration of the amines is modelled at design load and studied in off-design conditions for a combined cycle. Different ambient conditions and part-load strategies and their influence on the cycle performance are also examined. Of particular interest is a novel strategy with the possibility of longer life of gas turbine blading, with marginal loss in efficiency. The off-design performance of the combined cycle is ...

CERN Document Server

Recently the D{\\O} Collaboration reported an observation of like-sign charge asymmetry (CA), which is about $3.2 \\sigma$ deviation from the standard model (SM) prediction. Inspired by the observation we investigate the scalar unparticle effects, under the color charge of $SU(3)_c$ symmetry, in the CP violation in neutral B meson oscillations as well as the dispersive and absorptive parts of $\\bar B_q\\leftrightarrow B_q$ transition, which can be related to the CA directly. In order to illustrate the peculiar properties of unparticle, our analysis is carried out in two scenarios for the right-handed section: (I) $\\lambda_R=\\lambda_L$ and $U_D^R=U_D^L$, where $\\lambda_{L,R}$ and $U_D^{L,R}$ are the couplings and flavor mixing matrix of left- and right-handed section, respectively; (II) $\\lambda_R >> \\lambda_L$ and $U_D^R$ is completely a free parameter. In scenario I we found that the wrong- and like-sign CA cannot be changed ...

International Nuclear Information System (INIS)

Carbon-14 was analysed by direct absorption of carbon dioxide on the mixture of organic amine compound and scintillation cocktail then counted by low level liquid scintillation counter. This method can be applied for radiocarbon dating. In this study, the effects of carbon dioxide absorption, and counting efficiency were investigated using various commercial available cocktail. It was found that permafluor V and Ready Gel showed the highest carbon dioxide absorption whereas the Permafluor V showed the highest counting efficiency

KoreaScience (Korea)

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KoreaScience (Korea)

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KoreaScience (Korea)

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International Nuclear Information System (INIS)

Cylindrical test pieces of concrete are used for measurements of "2"2"2Rn exhalation rates. Except one flat end surface of a test piece, other parts of its exteriority are covered with sealant. Radon atoms can escape only through its end surface from the interior into the outside air. This treatment makes the radon transport in the concrete one dimensional phenomena. The piece is put in an airtight container. Time variations of radon concentrations in the air of the container are measured with a plane multiwire-electrode ionization chamber. From this result, the radon areal exhalation rate is deduced for the piece. Exhalation rates are measured for four pieces with different length. Then, the diffusion coefficient is obtained for radon in the concrete as (5.0 #+-# 1.0) x 10"-"8m"2s"-"1 (a one-block method). A two-block method has been invented to obtain simultaneously values of three parameters: diffusion coefficient, porosity of concrete, and radon production rate ...

Energy Technology Data Exchange (ETDEWEB)

A number of ion exchange materials are being evaluated as part of the Tank Waste Remediation System (TWRS) Pacific Northwest Laboratory (PNL) Pretreatment Project for the removal of {sup 137}Cs from aqueous tank wastes. Two of these materials are organic resins; a phenol-formaldehyde resin (Duolite CS-100) produced by Rohm and Haas Co. (Philadelphia, Pennsylvania) and a resorcinol-formaldehyde (RF) resin produced by Boulder Scientific Co. (Mead, Colorado). One of the key parameters in the assessment of the organic based ion exchange materials is its useful lifetime in the radioactive and chemical environment that will be encountered during waste processing. The focus of the work presented in this report is the radiation stability of the CS-100 and the RF resins. The scope of the testing included one test with a sample of the CS-100 resin and testing of two batches of the RF resin (BSC-187 and BSC-210). Samples of the exchangers were irradiated with a {sup 60}Co ...

Energy Technology Data Exchange (ETDEWEB)

Determination, uptake and distribution of various ions such as alkali metals in three different parts (leaf, stem and root) and seeds of radish (Kaiware daikon) were examined using flame emission spectrometry and ICP-AES. In order to examine the influence of concentration alkali metal ion concentration in the radish culture solution on the uptake and distribution of these metals, the radish was grown at pH 5.6 in solutions containing alkali metal chloride at concentrations ranging from 10{sup -5} to 10{sup -1} mol dm{sup -3}. When the radish were grown in culture solution with alkali metal ions of low concentrations (10{sup -5} and 10{sup -4} mol dm{sup -3}), Na, K, Rb and trace Li were detected in leaves, stems and roots while Cs was scarcely detected. However, the contents of Na, K, Li in these organs were the same as those in radish cultivated in pure water. An increase of Rb uptake was observed with an increased Rb concentration. In the ...

Energy Technology Data Exchange (ETDEWEB)

The chemistries of reactants, plasticizers, solvents and additives in an epoxy paint are discussed. Polyamide additives may play an important role in the absorption of molecular iodine by epoxy paints. It is recommended that the unsaturation of the polyamide additive in the epoxy cure be determined. Experimental studies of water absorption by epoxy resins are discussed. These studies show that absorption can disrupt hydrogen bonds among segments of the polymers and cause swelling of the polymer. The water absorption increases the diffusion coefficient of water within the polymer. Permanent damage to the polymer can result if water causes hydrolysis of ether linkages. Water desorption studies are recommended to ascertain how water absorption affects epoxy paint.

International Nuclear Information System (INIS)

Studies of the gastrointestinal absorption of lead-203 chloride were carried out on 11 normal subjects, 7 males and 4 females. Whole body counting of these subjects after administration of 74 kBq (2 #mu#Ci) of cyclotron-produced lead-203 chloride showed a mean absorption of 21.3% of the dose with a range from 10.4 to 47.7%. The male subjects had a lower mean absorption of 18.1% of the dose compared with a mean of 26.9% in the females. Although this difference did not reach statistical significance, it is postulated that male/female differences in absorption may relate to differences in iron saturation of the subjects.

UK PubMed Central (United Kingdom)

The use of stable indole-3yl-acetic acid (IAA) labeled by 6 atoms of ¹³C allowed, after [¹³C]IAA treatment, simultaneous gas chromatography-mass spectrometry quantifications of...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

One of the important aspects in an absorption system is the effectiveness in which the gas and liquid phases come into contact with each other. An effective absorption process will provide sufficient contacting area for the gas and liquid phases to interact upon. With this in mind, work was conducted to evaluate carbon dioxide (CO{sub 2}) absorption into aqueous solutions of monoethanolamine (MEA) using two different types of contacting devices: gas absorption membrane (GAM) modules and traditional packed columns. The performance of these two absorption devices was compared to one another using the overall mass transfer coefficient (K{sub G}a{sub v}) as a basis. The GAM module contained microporous polypropylene hollow fibre membranes and the packed absorption column contained Sulzer DX structured packing. The results indicate that GAM modules tend to have ...

Energy Technology Data Exchange (ETDEWEB)

The quantitative measurement of carbon concentration-distance curves serves as fundamental prerequisite for the evaluation of rim zone properties connected with decarburisation processes in material science. This was shown in part 1 of the present work with two samples from through-hardenable rolling bearing steel 100Cr6 (SAE 52100) austenitised in different oxidising atmospheres by position dependent determination of hardness, residual stresses, and X-ray line broadening ({l_brace}211{r_brace} {alpha}'-Fe diffraction line). In practice, it is important to predict carbon concentration-distance curves under prevailing heat treatment conditions or to conclude conversely from profile measurements. Based on a refined kinetics model of a diffusion-controlled process, part 2 therefore presents a simulation tool developed by means of the finite element method (FEM). Apart from the concentration dependence of the diffusion coefficient, it also ...

Energy Technology Data Exchange (ETDEWEB)

A method of assembling two or more parts together that may be metal, ceramic, metal and ceramic parts, or parts that have different CTE. Individual parts are formed and sintered from particles that leave a network of interconnecting porosity in each sintered part. The separate parts are assembled together and then a fill material is infiltrated into the assembled, sintered parts using a method such as capillary action, gravity, and/or pressure. The assembly is then cured to yield a bonded and fully or near-fully dense part that has the desired physical and mechanical properties for the part's intended purpose. Structural strength may be added to the parts by the inclusion of fibrous materials.

Science.gov (United States)

Photoelectron resonance capture ionization (PERCI) is a soft and sensitive ionization method, based on the attachment of low-energy (<1 eV) photoelectrons to organic analyte molecules. PERCI has been developed in our laboratory for the real-time analysis of organic particles by mass spectrometry, and is employed here to monitor the heterogeneous reaction of ozone with oleic acid. Simplified identification of the reaction products is possible as a result of the soft nature of PERCI, giving predominantly the [M--H](-) ions. The major particle-phase products are identified as: 1-nonanal, nonanoic acid, 9-oxononanoic acid, and azelaic acid, consistent with proposed mechanisms. New insight into this well-studied heterogeneous reaction is gained as additional minor particle-phase products, consistent with the Criegee mechanism, are readily detected. PMID:15468105

Energy Technology Data Exchange (ETDEWEB)

An x-ray diffraction technique for determining thin-film thickness is presented which should prove to be a valuable alternative to the array of spectroscopies (Rutherford backscattering spectrometry, Auger electron spectroscopy, etc.) currently favored for these measurements. Some of the virtues of this x-ray diffraction approach are its nondestructive nature, fast data acquisition rate (enabling in situ observations), thickness resolution better than 5 nm, and conventional equipment requirements. Results are shown for Pd/sub 2/Si thin films grown during isothermal annealing of Pd coatings (100 nm) on Si at 200 /sup 0/C for various amounts of time. A comparison of these x-ray measurements with Rutherford backscattering spectrometry data taken from the same specimens is used to demonstrate the validity of the x-ray technique.

UK PubMed Central (United Kingdom)

A method is reported which permits selective suppression of absorption of radioactive strontium from ingested food material, permitting the calcium to be available to the body. Studies were carried...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundSeveral aromatic amines (AA) could cause bladder cancer and are an occupational hygiene problem in the workplace. However, little is known about the percutaneous absorption...Full Text Available

UK PubMed Central (United Kingdom)

To investigate the fate of intrinsic factor and cobalamin during cobalamin absorption, we incubated enterocytes isolated from guinea pig ileum for periods of up to 30 min with ⁵⁷Co-labeled...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Concentration of an amine solution for removal of hydrogen sulfides and carbon dioxide from natural gas, is tested by carbon dioxide absorption measurement in an apparatus allowing complete reaction to give reliable results.

CERN Document Server

X11 Desktop Environments (KDE and GNOME) - Part II

CERN Document Server

Low Energy Part of the CONCERT High-Power Proton Linac

International Nuclear Information System (INIS)

... Part A: The electromagnetic radiation of a charged tachyon. Part B: Some

Energy Technology Data Exchange (ETDEWEB)

In this note it is suggested that binuclear platinum(II) complexes with a solely inorganic bridging pyrophosphito ligand also possess many of the complementary advantages of inorganic and organic dyes. They are evaluated for their potential use as a luminescent solar concentrator material. The disadvantages include: the high cost of platinum; the absorption spectra in solution shows a weaker absorption at 452 nm which may cause reabsorption of emitted light; the positions of the absorption and emission maxima are not at the optimal wavelengths for absorption of sunlight and emission to a solar cell. In spite of these drawbacks the author believes the platinum complexes merit consideration for fabrication of solar concentrator devices.

Science.gov (United States)

... significant change of spontaneous radiation intensity. It is very sensitive technique allowing the observation of small changes of light absorption. ...

International Nuclear Information System (INIS)

Rats and guinea pigs were fed "2"3"8Pu either biologically incorporated into alfalfa (by growth of the plant on soil containing Pu) or added as a solution to alfalfa, or were gavaged with a Pu solution. Depending upon the plant material fed, there appeared to be a twofold increase in "2"3"8Pu-gut absorption by the rat and a two- to fourfold increase in the guinea pig as compared with absorption from the Pu solution. The data, though limited and variable, suggest that Pu bound to plant tissue may have higher gut absorptivity than inorganic Pu in both herbivorous and nonherbivorous rodents.

Science.gov (United States)

... The data were transformed into total hemispherical emittance values and correlated with respect to ceramic coating thickness and temperature ...

Science.gov (United States)

... energy absorption characteristics of composite sandwich panels, thermoplastic energy-absorbing subfloor structures, and shoulder belt pre- tensioners. ...

International Nuclear Information System (INIS)

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

Energy Technology Data Exchange (ETDEWEB)

In studying the absorption of carbon dioxide by absorbents impregnated with alkanol amines, researchers used a laboratory-scale packed column to determine the overall gas-phase mass-transfer coefficients and enhancement factors. A model derived for the mechanism of the chemical reaction taking place in the interfacial layer accounts for the effect of the reaction upon the absorption rate better than other models.

Energy Technology Data Exchange (ETDEWEB)

The application of differential optical absorption (DOA) techniques for the in-situ determination of the chemical composition of coal gasification process streams is investigated. Absorption spectra of relevant molecular species and the temperature and pressure effects on DOA-determined spectral characteristics of these species will be determined and cataloged. A system will be configured, assembled, and tested.

Energy Technology Data Exchange (ETDEWEB)

The absolute absorption of ozone in the midinfrared has been measured relative to 253.7-nm ultraviolet absorption to an accuracy of 1% using a Bruker Fourier transform spectrometer. These new results agree with previous measurements by diode laser measurements after the latter are corrected for more recent infrared calculations and ultraviolet cross sections. They also agree with a determination based on refractive index measurements in the infrared. 16 refs., 4 figs., 3 tabs.

UK PubMed Central (United Kingdom)

We have developed a method to extract and separate phytochelatins (PCs)—metal(loid) complexes using parallel metal(loid)-specific (inductively coupled plasma-mass spectrometry) and organic-specific...Full Text Available

UK PubMed Central (United Kingdom)

A fast and sensitive LC-ESI-MS method is described for the comparative quantification of 16 estrogen metabolites based on the derivatization of estrogens with a novel derivatizing reagent, N-methyl-nicotinic...Full Text Available

UK PubMed Central (United Kingdom)

Charge-charge interactions dramatically influence the dissociation and proton transfer reactivity of large multiply protonated ions. In combination with tandem mass spectrometry, proton transfer...Full Text Available

International Nuclear Information System (INIS)

Reliable values of x-ray and gamma-ray attenuation coefficients of elements and compounds are required in spectrometry as well as in many other scientific, engineering and medical disciplines involving photon radiation

UK PubMed Central (United Kingdom)

BackgroundThe proteomics approach termed proteome pattern analysis has been shown previously to have potential in the detection and classification of breast cancer. Here we aimed...Full Text Available

UK PubMed Central (United Kingdom)

A liquid chromatography/tandem mass spectrometric (LC/MS/MS) assay was developed for the quantitative determination of salirasib (S-trans, trans-farnesylthiosalicylic acid,...Full Text Available

UK PubMed Central (United Kingdom)

In this study we have profiled the free sterol content of cerebrospinal fluid by a combination of charge tagging and liquid chromatography-tandem mass spectrometry. Surprisingly, the most abundant cholesterol...Full Text Available

International Nuclear Information System (INIS)

A new acquisition and evaluation procedure has been introduced for the measurement of time-dependent processes in gamma-ray spectrometry, in order to extract more information, including half-lives, from the data recorded during acquisition and to enable a more comprehensive analysis of the results. These advanced, off-line data evaluation techniques improve the selectivity and the background subtraction and make it possible to estimate the important analytical parameters (e.g., half-lives) more accurately than with the usual decay curve fitting method. (author)

International Nuclear Information System (INIS)

Correct prediction of the fission products inventory in irradiated nuclear fuels is essential for accurate estimation of fuel burnup, establishing proper requirements for spent fuel transportation and storage, materials accountability and nuclear forensics. Such prediction is impossible without accurate knowledge of neutron induced fission yields. The uncertainty of the fission yields reported in the ENDF/B-VII.0 library is not uniform across all of the data and much of the improvement is desired for certain fissioning isotopes and fission products. We discuss our measurements of cumulative fission yields in nuclear fuels irradiated in thermal and fast reactor spectra using Inductively Coupled Plasma Mass Spectrometry. (author)

International Nuclear Information System (INIS)

Mass spectrometry was instrumental in the discovery of the fullerenes and the characterization of their special structure (truncated icosahedron). High resolution and high sensitivity mass spectrometry in combination with a crossed molecular beam/electron beam ion source is used here to study a further, very unique property of singly and multiply charged fullerene ions (up to Z=7), i.e. their strong resilience towards decomposition via sequential C_2 evaporation and via Coulomb explosion, respectively. (author).

International Nuclear Information System (INIS)

The aim of this thesis is the study of new systems devoted to the real time neutron spectrometry and dosimetry. The microelectronics technologies have been used to research a micro system integrating sensor and data processing in real time. The multi range sensor is based on many pair of semiconductor diodes placed face to face and covered by lithium fluoride. The sensor has been designed and its behavior has been simulated. Its operating in reference neutrons beams has been analyzed. (A.L.B.)

Science.gov (United States)

Studies begun during the first year of this project on biopsies from spontaneous tumors in dogs and from human patients undergoing radiotherapy treatment were continued. The results indicate that significant fractions of the spontaneous tumors in dogs and cervical carcinomas in patients undergoing radiotherapy have a DNA content higher than normal diploid cells. The higher DNA content in tumor cells permits distinguishing them from normal cells in the biopsy material with the aid of flow microfluorometric (FMF) instrumentation or multiangle light-scatter spectrometry.

Energy Technology Data Exchange (ETDEWEB)

{sup 14}C is a is a long-lived beta-emitting nuclide (T{sub 1/2} = 5730 years) produced naturally in the upper atmosphere as a result of reactions between neutrons and stable {sup 14}N({sup 14}N(n,p){sup 14}C). Although in a lesser extent, nuclear power plants produce {sup 14}C as well during their routine operation. Since it is converted in {sup 14}CO{sub 2} and mixed throughout the atmosphere, it is incorporated into plant tissues, via photosynthesis process, and hence in food chain. Because of the biological importance of {sup 14}C and long half-life, it is of interest to quantify the amounts released by nuclear industry. The Brazilian nuclear central named Nuclear Central Admiral Alvaro Alberto (CNAAA) has two nuclear reactors of PWR type in operation, Angra I (657 MWe) and Angra II (1350 MWe), and one under construction, Angra III (1309 MWe PWR). The aim of this study was to determine the strength of the sources and the {sup 14}C content in the environment through analyses of air, ...

Energy Technology Data Exchange (ETDEWEB)

A new method that allows rapid preconcentration and separation of plutonium and neptunium in water samples was developed for the measurement of {sup 237}Np and Pu isotopes by inductively-coupled plasma mass spectrometry (ICP-MS) and alpha spectrometry; a hybrid approach. {sup 238}U can interfere with {sup 239}Pu measurement by ICP-MS as {sup 238}UH{sup +} mass overlap and {sup 237}Np via peak tailing. The method provide enhanced removal of uranium by separating Pu and Np initially on TEVA Resin, then moving Pu to DGA resin for additional removal of uranium. The decontamination factor for uranium from Pu is almost 100,000 and the decontamination factor for U from Np is greater than 10,000. This method uses stacked extraction chromatography cartridges and vacuum box technology to facilitate rapid separations. Preconcentration is performed using a streamlined calcium phosphate precipitation method. Purified solutions are split between ICP-MS and ...

British Library Electronic Table of Contents (United Kingdom)

Gastrointestinal patches represent a novel multiparticulate drug delivery system able to increase the intestinal absorption of drugs with poor bioavailability. The number of patches to administer is a critical issue since it is related to the surface and drug concentration at the absorption site. The objective of this article is to evaluate the effect of the number of administered patches on the final absorption of leuprolide, a peptide chosen as model drug, assuming complete adhesion of all the devices to the intestinal membrane. The same dose of leuprolide was encapsulated into 2, 4 and 6 patches; the resulting intestinal absorption profiles were measured with the Ussing chamber ex vivo experimental setup and compared between them. The results showed that varying the number of patches, t...

International Nuclear Information System (INIS)

The Polarized Gamma-ray Observer (PoGOLite) is a balloon-borne instrument that will measure gamma-ray polarization in the energy range 25-80 keV from astronomical sources such as pulsars, accretion discs and jets from active galactic nuclei. The two additional parameters provided by such observations, polarization angle and degree, will allow these objects to be studied in a new way, providing information about their emission mechanisms and geometries. The instrument measures azimuthal scattering angles of photons within a close packed array of phoswich detector cells (PDCs) based on coincident detection of Compton scattering and photoelectric absorption. Each PDC comprises three different scintillating components and combines photon detection, active collimation and bottom anticoincidence into one single unit. The three parts are viewed by a photomultiplier tube (PMT) and pulse shape discrimination is used to identify signals from dierent ...

International Nuclear Information System (INIS)

This support document summarized the results of botanical surveys conducted as part of a phytoremediation research project that catalogued plants found growing at a petroleum impacted site in Alberta. Phytoremediation refers to the growing of chosen plant species in a polluted site for a period of time in order for the plant to remove contaminants through its natural attributes of absorption, translocation, storage and excretion. Several different plant species with phytoremediation properties are being considered for wide scale bioremediation use. This document described the PhytoPet database which was originally developed as an inventory of plants with phytoremediation capabilities. It was designed to provide easy access to information and help users choose plants with the potential to phytoremediate petroleum hydrocarbons. The information in this document is intended for remediation specialists, site owners and managers as well as ...

Energy Technology Data Exchange (ETDEWEB)

Durability of 28 days compressive strength concrete of 20 to 120 MPa has been studied. The ability of concrete to transport aggressive agents has been determined for four properties: the air permeability, the chloride diffusivity, the water absorption and the carbonation. A chloride migration test for high and very high strength concrete (HSC and VHSC) has been built. The relationship between transport properties and the compressive strength after one and 28 days of humid curing has always the same shape: transport decreases when strength increases. However, transport properties often vary in the ordinary concrete field. Beyond, the domain is much more limited. The relationship between transport properties and strength valid for ordinary concrete can not be simply extrapolated for HSC and VHSC. To determine the part of microcracking of HSC and VHSC, concrete behaviour stored in two mediums has been studied: the ones shaming the storing ...

International Nuclear Information System (INIS)

Fully fluorinated compounds (perfluoro compounds) represent a class of chemicals which include many extremely inert species-inert to both chemical reaction and photodissociation. Well known examples include SF6 and the perfluorocarbons (PFCs) CF_4 and Teflon. SF_6 is used industrially in electrical switch gear and as an atmospheric tracer. CF_4 and C_2F_6 are released into the atmosphere as a by-product of aluminum manufacture. Several perfluoro compounds have been proposed as substitutes for the ozone-destroying Freons and halons; proposed substitutes include SF_6, c-C_4F_8, C_5F_1_2, and C_6F_1_4. These chemicals were chosen in part because they do not harm the stratospheric ozone layer and were therefore considered environmentally friendly. Recently, Ravishankara et al. reported that perfluoro compounds have significant global warming potential (GWP), contributing to the greenhouse effect due to strong infrared absorption. The perfluoro ...

International Nuclear Information System (INIS)

The optical spectra of actinide ions in the compound AnCl_3 and doped into single crystal LaCl_3 were interpreted in terms of transitions within 5f"N configurations. Energy-level calculations were carried out using an effective operator Hamiltonian, the parameters of which were determined by fitting experimental data. Atomic and crystal-field matrices were diagonalized simultaneously assuming an approximate D_3_h site symmetry. The spectroscopic data were taken from the literature but in most cases supplemented by unpublished measurements in absorption and in fluorescence. Spectroscopic data for each ion were analyzed independently, then the model parameters were intercompared and in many cases adjusted such that in the final fitting process the principal interactions showed uniform trends in parameter values with increasing atomic number. Consistent with analyses of the spectra of lanthanide ions in both LaCl_3 and LaF_3, abrupt changes in magnitude of certain ...

Science.gov (United States)

45 Public Welfare 3 2010-10-01 2010-10-01 false Appendix A to Part 611 A Appendix A to Part 611 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE...

Science.gov (United States)

The spectral dependences of absorption photoinduced in a pure bismuth titanium oxide crystal by 532-nm laser pulses are studied. It is shown that optical absorption in the crystal in the range from 492 to 840 nm increases with increasing exposure. The photoinduced absorption relaxes in the dark for more than 60 hours. A model of photoinduced absorption is proposed which assumes the population of two trap centres with the normal energy distribution law for the concentrations of electrons photoexcited from donors to the conduction band. This model well describes the spectral dependences of photoinduced absorption by using the average ionisation energies of the traps E{sub 1} = 1.60 eV and E{sub 2} = 2.57 eV. The model is used to estimate the increase in the photorefractive sensitivity of a bismuth titanium oxide crystal in the near IR region, which was earlier observed after exposing ...

Energy Technology Data Exchange (ETDEWEB)

Three typical Japanese coals of non-coking coal, coking coal and anthracite were heat-treated with KOH, and change in their pore structure was examined by absorption of N2, X-ray diffraction and TEM observation. In addition, the relation between a coal rank and pore structure was also studied by absorption experiment of N2. In experiment, the mixture of coal and KOH in a nickel holder was heat-treated in N2 gas flow at heating rate of 2{degree}C/min, and held at a fixed temperature for one hour. To clarify the pore structure, N2 absorption isotherms were measured at -196{degree}C under nearly 76cmHg using a commercially available full-automatic absorption measurement equipment. Based on the X-ray diffraction and TEM observation results on activated coals, the relation between the N2 absorption and pore structure was studied. The results are summarized as follows: (1) The yield and ...

Energy Technology Data Exchange (ETDEWEB)

The X-ray photoacoustic spectra of copper and brass (64.7 wt.% Cu and 35.3 wt.% Zn) have been measured at XANES (X-ray absorption near-edge structure) regions using synchrotron radiation. These spectra were compared with optical density of X-ray spectra. It is shown that the information derived from XANES is also included in the X-ray photoacoustic spectrum which reflects the heat production processes in copper and brass. However, the results showed that the increases and changes of the photoacoustic signal were different from those of the X-ray absorption coefficient at XANES regions. (author).

Energy Technology Data Exchange (ETDEWEB)

Absorption with aqueous amine solvents is at present the most viable technology for CO{sub 2} capture. While this is a proven technology, efforts are ongoing to improve it in order to make it a more attractive technology for large scale use to reduce CO{sub 2} emissions. Finding solvents with better properties is one approach to improving the technology. In this thesis methods in computational chemistry are used to improve the understanding of the chemistry of CO{sub 2} absorption in amine-water systems. The work is also intended to provide models that can be used to predict the performance of new solvents. Such predictive models are intended to facilitate the screening for new solvents

Science.gov (United States)

... Values of absorption maxima, X.nax, and associated molar extinction coefficients, c, as well as values of the n-octanol/water partition coefficient( ...

International Nuclear Information System (INIS)

Available in abstract form only. Full text of publication follows: In this study. simulation of carbon dioxide absorption by Sodium Hydroxide solution in a packed bed has been investigated. At first, mass and energy balances were applied around a differential height of the bed. So, the governing equations were obtained. Surface renewal theory by Danckwerts was used to represent the mass transfer operation Finally, by changing the operating parameters like solvent temperature, inlet gas composition pressure and height of the bed, the effect of these parameters on the absorption and the composition of carbon dioxide in exit stream have been investigated. (authors)

Energy Technology Data Exchange (ETDEWEB)

Application of an optimization technique to extract the non-ideal parameters of gas absorption with chemical reactions process was described. The gas absorption was modeled using mass transfer theory to represent the realistic behaviors of an absorber. The model was a highly non-linear iterative model which correlated the overall rate of absorption as the function of unknown non-ideal parameters, including the physical liquid mass transfer coefficient and the wetted interfacial area of of packings. The optimization program was developed to minimize the sum of squares of relative errors between the model predictions and the experimental data. Four sets of experimental data (case studies) with different operating conditions were used for extracting parameters. Comparisons between predicted and experimental measured overall absorption rate were in good agreement, average absolute value of relative errors ...

Science.gov (United States)

in early 1992 from Lord Corporation, were also found. For both the reflective and absorptive polyurethanes, the fresh paint fluoresces significantly ...

International Nuclear Information System (INIS)

... School of Plant Biology. v. 23(2) p. 316-322. carbon dioxide absorption carbon

International Nuclear Information System (INIS)

Deferoxamine (DFA) (250 mg/kg), orally administered to rats, decreased Pu absorption from orally administered "2"3"8Pu(NO_3)_4 by about 1/3. The calcium salt of diethylenetriaminepentaacetic acid (Ca-DTPA), given orally 5 to 10 min after the Pu, increased absorption about four times. DFA given 10 min before the DTPA decreased the effect of the latter by a factor of two. Deferoxamine administration prior to inhalation treatment of man with DTPA may be one way to decrease possible DTPA-enhanced gut absorption of Pu.

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

The transfer of /sup 203/Pb and/or /sup 47/Ca across the intestinal epithelium of the chick was investigated, with emphasis given to the functional role of cholecalciferol (vitamin D-3). /sup 203/Pb, after introduction in the intestinal lumen, is rapidly accumulated by the intestinal tissue, and only a fraction of /sup 203/ Pb is translocated parenterally (absorbed). Cholecalciferol did not significantly affect the accumulation of /sup 203/Pb by intestinal tissue but did accelerate /sup 203/Pb movement across the basal-lateral membrane. In contrast, cholecalciferol both decreased /sup 47/Ca tissue levels and increased /sup 47/Ca absorption. In rachitic chicks, the rate of absorption of /sup 203/Pb was greater in the distal than in the proximal segments of the intestine; after cholecalciferol repletion, the degree of absorption in all segments was similar, indicating the order of cholecalciferol effectiveness as duodenum ...

Energy Technology Data Exchange (ETDEWEB)

The significant and rapid reduction of greenhouse gas emissions is recognized as necessary to mitigate the potential climate effects from global warming. The postcombustion capture (PCC) and storage of carbon dioxide (CO{sub 2}) produced from the use of fossil fuels for electricity generation is a key technology needed to achieve these reductions. The most mature technology for CO{sub 2} capture is reversible chemical absorption into an aqueous amine solution. In this study the results from measurements of the CO{sub 2} absorption capacity of aqueous amine solutions for 76 different amines are presented. Measurements were made using both a novel isothermal gravimetric analysis (IGA) method and a traditional absorption apparatus. Seven amines, consisting of one primary, three secondary, and three tertiary amines, were identified as exhibiting outstanding absorption capacities. Most have a number of ...

UK PubMed Central (United Kingdom)

Aerosol particles are ubiquitous in the troposphere and exert an important influence on global climate and the environment. They affect climate through scattering, transmission, and absorption of...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The bulk removal of CO/sub 2/ from industrial gases is a frequently applied process in the field of gas-treating. Usually chemical solvents are used in order to increase both the solvent-loading capacity and the absorption rate. These solvents often are aqueous solutions of alkanolamines. The loaded-liquid is regenerated at high temperatures with the aid steam. In the present study absorption rates are experimentally determined in various mixtures of amines over a wide range of concentrations. Simultaneously, a model was developed for the description of mass transfer accompanied by parallel reversible chemical reactions. The equations of this mass transfer model could not be solved analytically and therefore numerical techniques were used to obtain an exact description of this process. This model also includes the asymptotic situations of homogeneous catalysts and shuttle mechanism for which in the literature several approximate solutions have ...

Science.gov (United States)

The recent development of matrix-assisted UV laser desorption (LD) mass spectrometry has made possible the ionization and detection of extremely large molecules (with molecular weights exceeding 100,000 Daltons). This technique has generated enormous interest in the biological community for the direct examination of large peptides and oligonucleotides. Although this matrix-assisted ionization method has been developed and used almost exclusively with time-of-flight (TOF) mass spectrometers, research is currently in progress to demonstrate this technique with trapped ion mass spectrometers, such as Fourier transform ion cyclotron resonance mass spectrometry (FTMS). The potential capabilities of FTMS for wide mass range, high resolution measurement, and ion trapping experiments suggest that this instrumental technique should be useful for the detailed structural characterization of large ions generated by the matrix-assisted technique. We have ...

Energy Technology Data Exchange (ETDEWEB)

Double-crystal high-resolution X-ray fluorescence spectrometry was applied to the state analysis of sulfur in coal and related fly ash. For total sulfur, a proportional relationship exists between fluorescence intensities and the analytical values obtained by the oxygen-combustion method. Two oxidation states of sulfur were identified by a least square curve fitting method, by assuming that the spectrum profile is identical for each sulfur state but the intensity and the position are different. Sulfur in coal mainly consists of S/sup 2 -/, whereas that in coal fly ash mainly consists of S/sup 6 +/. As much as 0.04-0.08% of S/sup 2 -/ remains in fly ash.

International Nuclear Information System (INIS)

A high-precision Li isotope analysis was developed for determining the Li"+ ion emitted from lithium phosphate as an ion source material by a Re double-filament ionization method in the thermal ionization mass spectrometry. In this method, Li isotopic fractionation is distinctly less sensitive to the filament temperature than those in the previous methods, and stable and high ion beam intensity of more than 8 x 10"-"1"1 A for "7Li is obtained. These advantages in determining the "7Li/"6Li ratio result in the analytical reproducibility of 0.26 per mille (1#sigma#). Furthermore, the sample preparation is simple and the low temperature (850degC) required by this method ensures the analysis of the isotopic composition of small amounts of Li with less influence of Li contamination to the sample, compared with the previous methods. (author).

British Library Electronic Table of Contents (United Kingdom)

The effect of sugar on plant metabolism, which is known to be similar to hormone-like signaling, was metabolomically studied using Melissa officinalis (lemon balm). The metabolite profiles of M. officinalis treated with sucrose were analyzed by gas chromatography-mass spectrometry (GC-MS) and principal component analysis (PCA). A total of 64 metabolites from various chemical classes including alcohols, amines, amino acids, fatty acids, inorganic acids, organic acids, phosphates, and sugars were identified by GC-MS. Three groups treated with different sucrose concentrations were clearly separated by PCA of their metabolite profiles, indicating changes in the levels of many metabolites depending on the sucrose concentration. Metabolite profiling revealed that treatment with a higher sucrose ...

International Nuclear Information System (INIS)

The indium implant damage and diffusion behavior in thin silicon-on-insulator (SOI) with a 200 nm top silicon layer were studied for different implantation energies and doses. Rutherford backscattering spectrometry in the channeling mode (RBS/C) was used to characterize the implant damage before and after annealing. Secondary ion mass spectrometry (SIMS) was used to study the indium transient enhanced diffusion (TED) behavior in the top Si layer of the SOI structure. An anomalous redistribution of indium after relatively high energy (200 keV) and dose (1 x 10"1"4 cm"-"2) implantation was observed in both bulk Si and SOI substrates. However, there exist differences in these two substrates that are attributable to the more predominant out-diffusion of indium as well as the influence of the buried oxide layer in the SOI structure.

British Library Electronic Table of Contents (United Kingdom)

Successful electron capture dissociation (ECD) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) applications to peptide and protein structural analysis have been enabled by constant progress in implementation of improved electron injection techniques. The rate of ECD product ion formation has been increased to match the liquid chromatography and capillary electrophoresis timescales, and ECD has been combined with infrared multiphoton dissociation in a single experimental configuration to provide simultaneous irradiation, fast switching between the two techniques, and good spatial overlap between ion, photon, and electron beams. Here we begin by describing advantages and disadvantages of the various existing electron injection techniques for ECD in FT-ICR MS. We next ...

British Library Electronic Table of Contents (United Kingdom)

High molecular weight products of the ozonolysis reaction of particle-phase 9-octadecenoic acid (oleic acid) have been studied by photoelectron resonance capture ionization (PERCI) mass spectrometry (MS). Oleic acid particles ( Formula Not Shown , Formula Not Shown ) were reacted with ozone (1.8x10-4atm) in a flow reactor at reaction times of 8 and 23s. Particles were sampled on-line with a differentially pumped particle inlet and chemically analyzed by PERCI-MS. PERCI is a soft ionization method that permits the direct measurement of relatively high molecular weight compounds, facilitating molecular identification. In addition to cyclic oxygenates, such as secondary ozonides and geminal diperoxides that were reported previously, we demonstrate the formation of polymers at the particle sur...

International Nuclear Information System (INIS)

The paper describes novel analytical methods developed for the detection of previous neutron irradiation and reprocessing of illicit nuclear materials, which is an important characteristic of nuclear materials of unknown origin in nuclear forensics. Alpha spectrometry and inductively coupled plasma sector-field mass spectrometry (ICP-SFMS) using solution nebulization and direct, quasi-non-destructive laser ablation as sample introduction were applied for the measurement of trace-level "2"3"2U, "2"3"6U and plutonium isotopes deriving from previous neutron irradiation of uranium-containing nuclear materials. The measured radionuclides and isotope ratios give important information on the raw material used for fuel production and enable confirm the supposed provenance of illicit nuclear material.

British Library Electronic Table of Contents (United Kingdom)

Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more attention to the threat of antibiotics to coastal ecosystems, researchers have often focused on relatively few antibiotics, because of the absence of suitable analytical methods. We have therefore developed a method for the rapid detection of 36 antibiotic residues in coastal waters, including tetracyclines (TCs), sulfanilamides (SAs), and quinolones (QLs). The method consists of solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, using electrospray ionization (ESI) in positive mode. The SPE was performed with Oasis HLB and Oasi...

Energy Technology Data Exchange (ETDEWEB)

The alpha particle induced fission of {sup 209}Bi has been investigated for E{sub {alpha}} = 55.7 and 58.6 MeV using gamma ray spectrometry. The cross sections for the production of fission products have been determined. The mass distributions have been found to be broad with a peak near mass 104. The charge distribution has been studied at the same particle energies. The fractional cumulative yields of {sup 97}Zr, {sup 99}Mo, {sup 101}Mo, {sup 112}Pd and {sup 117m}Cd have been determined using gamma ray spectrometry. The width of charge distribution is broad. (orig.).

Science.gov (United States)

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

International Nuclear Information System (INIS)

Full text of publication follows: Understanding the dynamic irradiation effects on silica glasses is important for developing the diagnostic systems used in fusion and fission environments. While fundamental defects having an un-pared electron such as the E' center have been extensively studied, the neutral oxygen deficiency defects have been insufficiently clarified for lack of the detection methods. The ion induced luminescence is one of the probes that can be used to detect non-paramagnetic defects, and to observe creation and annihilation behavior dynamically. In the present study, we examined the characteristics of the ion induced luminescence such as energy, fluence flux and temperature dependence of the luminescence efficiency to analyze damage process quantitatively. Samples of SiO2 glasses were commercially available fused and synthesized silica glasses, produced by Toshiba Ceramics, Co. Ltd.. A thin films of SiO2 deposited on a Si wafer was used to determine the luminescence ...

Environmental Research Database

DescriptionIn young pigs the post-weaning period is generally characterised by a marked reduction in voluntary feed intake, poor growth and development, and diarrhoea. The associated reduction in digestive and absorptive capacity of the gastrointestinal tract decreases the overall efficiency of nutrient capture and utilisation, thereby causing an increase in nutrient loading to the environment. The reduction in digestive and absorptive efficiency after weaning has implications for lifetime performance be [continued...

International Nuclear Information System (INIS)

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

Energy Technology Data Exchange (ETDEWEB)

The kinetics of the reaction of carbon dioxide in MDEA solutions were studied both experimentally and theoretically. It is concluded that MDEA acts as a homogeneous catalyst for CO/sub 2/ hydrolysis, and as a result the rate of absorption in aqueous MDEA solutions is significantly larger than one would calculate by simply taking into account the alkalinity of the reaction. A possible zwitterion mechanism is proposed for this reaction. The minor effect of ionic strength were also studied with the presence of other ions. 19 references, 6 figures.

International Nuclear Information System (INIS)

During electrolysis of a "2"4"8Cm(III) solution in 2M K_2CO_3 at pH=13, partial oxidation of curium to a higher oxidation state, probably Cm(IV), was observed. The absorption spectra of Cm(III) and Cm(IV) in K_2CO_3 solution were recorded and the molar extinction coefficients of main absorption bands of curium were evaluated. (author).

Energy Technology Data Exchange (ETDEWEB)

The carbon content of silicon single crystals and polycrystals has been measured by charged particle activation analysis (CPAA) and infrared absorption. The authors obtained a linear relationship between the absorption coefficient at 605 cm/sup -1/ and the carbon content obtained by CPAA. They obtained a conversion factor of (1.00 +- 0.03) 10/sup 17//cm/sup 2/ for a 100% substitutional carbon.

Energy Technology Data Exchange (ETDEWEB)

A model for combined mass and heat transfer during nonisothermal gas absorption in a two-phase gas- liquid bubbly medium with a high gas content and/or large times of gas-liquid contact is suggested. Diffusion and thermal interactions between bubbles is taken into account in the approximation of a cellular model of a bubbly medium whereby a bubbly medium is viewed as a periodic structure consisting of identical spherical cells with periodic boundary conditions at a cell boundary. Distribution of concentration of dissolved gas, temperature distribution in liquid and coefficients of mass and heat transfer during nonisothermal absorption of a soluble pure gas from a bubble by liquid are determined. In the limiting case of absorption without heat release the derived formulas recover the expressions for isothermal absorption. (orig.). With 1 fig., 1 tab. [Deutsch] Es wird ein Modell vorgestellt, das den ...

International Nuclear Information System (INIS)

An numerical method was developed for measuring radiant temperature using a set of absorption-foils coupled to soft x ray streak camera, SXRSC, in laser plasma experiments. An numerical code, SCC, was given. An x-ray intensity ratio vs temperature was calculated for Parylene, C_3H_6, Mylar and Aluminium. A suitable range of the measuring temperature was discussed to some absorber.

CERN Document Server

Recent high spatial and spectral resolution investigations of the diffuse interstellar medium (ISM) have found significant evidence for small-scale variations in the interstellar gas on scales less than or equal to 1 pc. To better understand the nature of small-scale variations in the ISM, we have used the KPNO WIYN Hydra multi-object spectrograph, which has a mapping advantage over the single-axis, single-scale limitations of studies using high proper motion stars and binary stars, to obtain moderate resolution (~12 km/s) interstellar Na I D absorption spectra of 172 stars toward the double open cluster h and Chi Persei. All of the sightlines toward the 150 stars with spectra that reveal absorption from the Perseus spiral arm show different interstellar Na I D absorption profiles in the Perseus arm gas. Additionally, we have utilized the KPNO Coude Feed spectrograph to obtain high-resolution (~3 km/s) interstellar Na I D ...

International Nuclear Information System (INIS)

The absorption spectra of plutonium ions in nitric acid have been described. There is a characteristic change in the absorption spectra of Pu v in lithium nitrate solutions. In 2 M-lithium nitrate a new peak at 969 nm and high absorption at 1200 nm are noticed. A decrease in the absorption by about 20% and the appearance of a new shoulder at 1120 nm in 6 M-lithium nitrate are found. There is no change in the spectrum in 4 M-lithium nitrate. The absorption spectra of plutonium ions in the spectral range 200 - 400 nm are interesting. All plutonium ions have an intense band in the region 250 - 260 nm as well as a less intense and rather diffuse band at 320 - 330 nm in lithium nitrate solutions the sharp band at 250 - 260 nm has disappeared. This suggests that this band is very sensitive to the environmental field. The band is probably produced by 5 F"q#-># 5 f"q"-"1 6 d transition ...

Energy Technology Data Exchange (ETDEWEB)

This chapter is concerned with standards and guidances for limiting radiation exposures. It is divided into three sections, each of which has several parts. Section 1: Ionizing Radiation -- Standards and Guidances Applicable to the Public: Part A, Radiation Protection Standards; Part B, Environmental Radiation Standards; Part C, Exempt Levels of Radioactivity; Part D, Protective Action Guides for Accidents. Section 2: Ionizing Radiation -- Standards Applicable to the Workplace. Section 3: Medical and Other Standards.

Energy Technology Data Exchange (ETDEWEB)

An indoor survey in order to estimate the population exposure in five towns of an Italian Region is presented. A particular methodology for the campaign was planned and is being applied. Gamma spectrometry of building materials, exposure rate measurements indoors and outdoors and radon concentration measurements indoors were taken with different techniques. A correlation was found between mean gamma exposure rate and mean radon concentration in the houses investigated. An evaluation of mean effective dose equivalents for the inhabitants of the five towns is reported.

International Nuclear Information System (INIS)

We describe the continued development of a portable, real-time neutron spectrometer. The spectrometer is composed of two distinct detector systems: a Helium 3 gas filled proportional counter for the lower neutron energy interval between 20 KeV and 2 MeV and a bulk silicon solid state detector for the higher energy interval between 2 MeV and 500 MeV. Modeling and experimental results with mono-energetic neutron beams are reported.

Energy Technology Data Exchange (ETDEWEB)

Following a recent refurbishment of the NPL Thermal Neutron Facility, the spectrum of the epithermal and fast neutron component of the beam produced by the thermal column of this facility was measured over the energy range from thermal to 20 MeV using a Bonner sphere spectrometry system. The effect of the presence of epithermal and fast neutrons on the measured response of commonly-used thermal neutron dosemeters was calculated. (author)

Science.gov (United States)

Organic molecules are a significant and highly varied component of atmospheric aerosols. Measurement of aerosol composition and improvements in our understanding of the complex chemistry involved in their formation and aging are being aided by innovations in soft ionization aerosol MS. (To listen to a podcast about this feature, please go to the Analytical Chemistry multimedia page at pubs.acs.org/page/ancham/audio/index.html.). PMID:21275431

UK PubMed Central (United Kingdom)

We have used intramolecular cross-linking, MS, and sequence threading to rapidly identify the fold of a model protein, bovine basic fibroblast growth factor (FGF)-2. Its tertiary structure was probed...Full Text Available

International Nuclear Information System (INIS)

Natural radioactive materials were used for detector calibration. We found that KCl is a very suitable material for this purpose. The efficiency curve shape was derived by using #gamma# ray lines of "2"1"4Bi normalised using a known quantity of KCl in the same geometry. The best fit was found by the least squares method. The summing correction coefficients for "2"1"4Bi are determined. (orig.).

International Nuclear Information System (INIS)

The IGC-30 HPGe detector with MCA 'CANBERRA-10 PLUS' allows to determine surface contamination of areas of any type with a minimum error in radius 8-10 m, at a 'uniform' contamination. A modification of the CANBERRA hardware and software is described allowing determination of both the activity of a possible 'radioactive spot' and the activity of the whole observed surface. (author).

Energy Technology Data Exchange (ETDEWEB)

We have undertaken a study of ion mobility resolution in a miniature ion mobility spectrometer with a drift channel 1.7 mm in diameter and 35 mm in length. The device attained a maximum resolution of 14 in separating ions of NO, O{sub 2}, and methyl iodine. The ions were generated by pulses from a frequency-quadrupled Nd:YAG laser. Broadening due to Coulomb repulsion was modeled theoretically and shown experimentally to have a major effect on the resolution of the miniature device.

Energy Technology Data Exchange (ETDEWEB)

An energy dispersive x-ray fluorescence technique was used for the determination of Titanium (Ti) and Zirconium (Zr) in red mud by using a standard addition method. An annular {sup 241}Am source is employed for excitation of K shells of elements. 13 refs., 2 figs., 1 tab.

International Nuclear Information System (INIS)

By treatment of ?-substituted acetylacetone derivatives with boron trifluoride etherate a series of earlier unknown boron difluoride complexes is obtained. The series includes binuclear complexes containing boron in the chelate fragment connected via sulfur or selenium atom. Gas chromatographic and spectral characteristics of the obtained compounds were investigated. By means of chromato-mass spectrometry their reaction with hydrazine in acidic and alkaline media was studied

Energy Technology Data Exchange (ETDEWEB)

This file is devoted to the Chernobyl accident. It is divided in four parts. The first part concerns the accident itself and its technical management. The second part is relative to the radiation doses and the different contaminations. The third part reports the sanitary effects, the determinists ones and the stochastic ones. The fourth and last part relates the consequences for the other European countries with the case of France. Through the different parts a point is tackled with the measures taken after the accident by the other countries to manage an accident, the cooperation between the different countries and the groups of research and studies about the reactors safety, and also with the international medical cooperation, specially for the children, everything in relation with the Chernobyl accident. (N.C.)

Energy Technology Data Exchange (ETDEWEB)

The role of dietary calcium and phosphorus in modifying the intestinal absorption of lead and also the effect of lead ingestion on the metabolism of cholecalciferol were studied in chicks. The efficiency of absorption of /sup 203/Pb and /sup 47/Ca was increased when the animals were fed a low calcium diet and treated with cholecalciferol. The synthesis of the vitamin D-induced calcium-binding protein (CaBP) was correspondingly increased. When the chicks were depleted of vitamin D and repleted with 1,25-dihydroxycholecalciferol (1,25(OH)/sub 2/D/sub 3/) as their only source of the vitamin, the absorption of both /sup 47/Ca and /sup 203/Pb was unaffected by dietary calcium levels, and no change in CaBP levels occurred. Low dietary intake of phosphorus resulted in an increase in /sup 47/Ca and /sup 203/Pb absorption and in CaBP synthesis when the animals were treated with cholecalciferol. However, when the ...

Energy Technology Data Exchange (ETDEWEB)

Fourier transform infrared absorption spectroscopy has been used for the determination of the line strengths of 41 CO and CO[sub 2] absorption lines at temperatures between 295 and 1250 K. The CO vibrational-rotational lines were from the [ital P] branch of the fundamental absorption band (2150--1950 cm[sup [minus]1]) while the CO[sub 2] vibrational-rotational lines were from the far wing of the [ital R] branch of the [nu][sub 3] fundamental band (2395--2380 cm[sup [minus]1]). The intensities of the lines were measured from absorption spectra recorded in a high-temperature gas cell containing known concentrations of CO/CO[sub 2]/N[sub 2] gas mixtures at atmospheric pressure. Absorption spectra were recorded through the cell with the use of a moderate-resolution Fourier transform infrared spectrometer. The absorption spectra were mathematically corrected for ...

Energy Technology Data Exchange (ETDEWEB)

A laser resonance absorption spectrometer is used to investigate the characteristics of both self and nitrogen collision broadened carbon dioxide in resonance with He--Ne laser radiation at 4.2 ..mu..m. The absorption coefficient in these broadening conditions has contributions from the R(28) to R(34) absorption lines of the ..nu../sub 3/ CO/sub 2/ spectrum. The Fletcher-Powell optimization method is used to reduce the raw absorption data and to find the best value average collision broadening coefficient and laser emission frequency for a Lorentzian line shape model of the contributing lines. Pure carbon dioxide absorption in a pressure range of from 0.0016 atm (1.25 Torr) to 0.33 atm (250 Torr) is described well by the model with an average self broadening coefficient of 0.084 +- 0.008 cm/sup -1/ atm/sup -1/ for laser frequencies located at either 2370.591 +- 0.020 cm/sup -1/ or ...

CERN Document Server

Industrial-process control valves Part2 : Flow capacity Section Four : Inherent flow characteristics and rangeability

Energy Technology Data Exchange (ETDEWEB)

There are two types in quench distortion of steel parts: thermal distortion and transformation distortion. Quench distortion is caused mainly by uneven cooling rate of steel parts from Austenitising temperature. The rapid cooled side is lengthened (convex deformation); the slow cooled side is shortened (concave deformation). So, to control the quench distortion, it is necessary to regulate the cooling rate of steel parts during quenching. TWO COMPONENTS produce the quench distortion of steel parts: the thermal stress and transformation stress. Generally, the effect of the thermal stress on the quench distortion is stronger than the transformation stress. The quench distortion is caused by uneven cooling rate of the steel parts, from Austenitising temperature to Ms point and Ms-Mf range. So, to control the quench distortion, it is very important to regulate the cooling rate of the ...

British Library Electronic Table of Contents (United Kingdom)

We fabricate a low noise erbium-doped fiber ring laser that can be continuously tuned over 102nm by insertion of the fiber Fabry-Perot tunable filter (FFP-TF) in the ring cavity with a novel cavity structure and the optimal gain medium length. As an application of this fiber ring laser, we performed the absorption spectroscopy of acetylene (13C2H2) and hydrogen cyanide (H13C14N) and measure the absorption spectra of more than 50 transition lines of these gases with an excellent signal to noise ratio (SNR). The pressure broadening coefficients of four acetylene transition lines are obtained using this fiber ring laser and an external cavity laser diode.

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.

Science.gov (United States)

The development of new efficient afterglow phosphors is currently hampered by a limited understanding of the persistent luminescence mechanism. Radioluminescence (RL) and x-ray absorption measurements on the persistent phosphor SrAl2O4:Eu,Dy were combined to reveal possible valence state changes for the rare earth (co)dopants. Traps in the phosphor material are quickly filled when exposing thermally emptied SrAl2O4:Eu,Dy powder to x rays. On the same time scale a partial oxidation of Eu2+ to Eu3+ is observed by x-ray absorption near-edge spectroscopy (XANES), while for the trivalent dysprosium the valence state remains unchanged. The impact of these observations on the recently proposed models for persistent luminescence is discussed.

International Nuclear Information System (INIS)

We have measured K-edge X-ray absorption spectra of argon in sputtered aluminum films at a synchrotron radiation facility (the Photon Factory). We found that the energy and shape of white line change when the film is annealed at 500 C and the spectrum becomes resembling that of argon implanted in silicon. From the analyses of the X-ray absorption spectra and TEM observation we concluded that argon exists as very small atom clusters with a diameter less than 1 nm or exist as isolated atoms in the as-sputtered aluminum film, and that the size of the clusters become as big as 10 nm diameter when the film is heated. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

CERN Document Server

In their Letter [Phys. Rev. Lett. 92, 121302 (2004)] (also [Astron. Astrophys. 417, 853 (2004)]), Srianand et al. analysed optical spectra of heavy-element species in 23 absorption systems along background quasar sight-lines, reporting limits on relative variations in the fine-structure constant: da/a=(-0.06+/-0.06) x 10^{-5}. Here we demonstrate basic flaws in their analysis, using the same data and absorption profile fits, which led to spurious values of da/a and significantly underestimated uncertainties. We conclude that these data and fits offer no stringent test of previous evidence for a varying alpha.

Energy Technology Data Exchange (ETDEWEB)

A mass transfer model has been developed to describe the rate of absorption (or desorption) of H{sub 2}S and CO{sub 2} in aqueous blends of a tertiary and a secondary or a primary amine. The model is based on penetration theory, and all significant chemical reactions are incorporated in the model. The reactions are taken to be reversible, with reactions involving only a proton transfer considered to be at equilibrium. The particular amines studied in this research were methyldiethanolamine (MDEA), a tertiary amine, and diethanolamine (DEA), a secondary amine. Key physicochemical data needed in the model, such as diffusion coefficients, kinetic rate constants, and gas solubilities, were measured. Experimental absorption rates of CO{sub 2} and H{sub 2}S were measured in a model gas-liquid contacting device and were compared with model predictions. Experiments were carried out for single amine solutions (both MDEA and DEA) and for amine blends.

CERN Document Server

We describe a method of determining the system parameters in non-eclipsing interacting binaries. We find that the extent to which an observer sees the shape of the Roche-lobe of the secondary star governs the amount of distortion of the absorption line profiles. The width and degree of asymmetry of the phase-resolved absorption line profiles show a characteristic shape, which depends primarily on the binary inclination and gravity darkening exponent. We show that, in principle, by obtaining high spectral and time resolution spectra of quiescent cataclysmic variables or low mass X-ray binaries in which the mass-losing star is visible, fitting the shape of absorption line profiles will allow one to determine not only the mass function of the binary, but also the binary inclination and hence the mass of the binary components.

International Nuclear Information System (INIS)

The molar extinction coefficients at the absorption maximum of the solvated electron spectrum have been evaluated to be 900, 970, and 1000 mol-1?m2 for 1,2-ethanediol (12ED), 1,2-propanediol (12PD), and 1,3-propanediol (13PD), respectively. These values are two-third or three-fourth of the value usually reported in the published report. Picosecond pulse radiolysis studies have aided in depicting the radiolytic yield of the solvated electron in these solvents as a function of time from picosecond to microsecond. The radiolytic yield in these viscous solvents is found to be strongly different from that of the water solution. The temperature dependent absorption spectra of the solvated electron in 12ED, 12PD, and 13PD have been also investigated. In all the three solvents, the optical spectra shift to the red with increasing temperature. While the shape of the spectra does not change in 13PD, a widening on the blue side of the ...

UK PubMed Central (United Kingdom)

Assessments of drinking water safety rely on the assumption that ingestion represents the principal route of exposure. A review of the experimental literature revealed that skin penetration rates for...Full Text Available

CERN Document Server

Lyman-limit absorption systems can play many important roles during and after cosmological reionization. Unfortunately, due to the prohibitively large dynamic range required, it is impossible to self-consistently include these systems in cosmological simulations. Using fast and versatile semi-numeric simulations, we systematically explore the spatial distribution of absorption systems during and following reionization. We self-calibrate the resulting number of absorbers to the mean free path (mfp) of the ionizing ultraviolet background (UVB), and present results at a given mfp and neutral hydrogen fraction. We use a simple optical depth criterion to identify the locations of absorbers. Our approach is fairly robust to uncertainties such as missing subgrid structure. Unlike at lower redshifts where the UVB is relatively uniform, at higher redshifts the fluctuations in the UVB and the HII morphology of reionization can drive the large-scale ...

UK PubMed Central (United Kingdom)

U.v.-visible-absorption and e.p.r. spectroscopy were used to study the type 2 and type 3 copper centres in the mercury derivative of laccase. After treatment with peroxide the mercury derivative of...Full Text Available

UK PubMed Central (United Kingdom)

The rate-limiting step in the transit of dietary fat across the intestinal absorptive cell is its exit from the endoplasmic reticulum (ER) in a specialized ER-to-Golgi transport vesicle, the prechylomicron...Full Text Available

International Nuclear Information System (INIS)

Laser-induced change is studied of the optical absorption and luminescence due to F-H pairs generated by an electron pulse in SrF_2. It is found that laser irradiation near 2.34 eV at a delay of 26 #mu#s after an electron pulse by which F-H pairs are generated reduces the component I of the pairs that has a decay time of 59 #mu#s and optical absorption bands at 2.34 and 4.13 eV and enhances the component II that has a decay time of 7.7 ms and has optical absorption bands at 2.7 and 3.35 eV. Laser irradiation near 2.7 eV at a delay of 4 ms after the electron pulse is found to induce the reverse reaction. Studies of dichroism of the laser-induced reduction and enhancement of the optical absorption bands and the luminescence reveal that the direction of the #SIGMA#-#SIGMA# transition of the F_2"- molecular ion is converted by the transformation from I to II and vice versa. It is suggested that the ...

International Nuclear Information System (INIS)

Optical absorptance spectra of A-15 compounds were taken using a calorimetric technique in the range 0.2 eV to 4.0 eV. Thermomodulation spectra were taken on several A-15 sputtered films.

International Nuclear Information System (INIS)

The experiments at the incinerator for low-level wastes processing, (containing transuranium radionuclides) are described. Air decontamination factors and detector readings correction factors for efficiency and absorption are indicated.

UK PubMed Central (United Kingdom)

Bisulfite reductase (desulfoviridin) and an assimilatory sulfite reductase have been purified from extracts of Desulfovibrio vulgaris. The bisulfite reductase has absorption maxima...Full Text Available

International Nuclear Information System (INIS)

2,3-Dimercaptosuccinic acid (DMSA) is a new orally active heavy metal chelator for the treatment of childhood Pb intoxication on an outpatient basis. The influence of DMSA, as well as other chelating agents, on gastrointestinal 203Pb absorption and whole-body "2"0"3Pb retention was examined. Groups of Sprague-Dawley rats (230-260 g) were gavaged with a solution containing approximately 25 mg/kg Pb [as Pb(NO_3)2] plus 15 microCi "2"0"3Pb. Some groups were then immediately given 0.11 mmol/kg of either DMSA, CaNa2EDTA, D-penicillamine, or BAL by oral gavage, while other groups received the same drugs by ip injection. Control groups received solutions of the drug vehicles po or ip. Whole-body Pb retention and gastrointestinal Pb absorption (whole body retention + urinary Pb excretion) were significantly decreased in rats that received DMSA po. This finding implies that the use of DMSA to treat childhood lead intoxication on an outpatient basis is ...

Science.gov (United States)

... the hydroxyl group with the benzene ring. The molar extinction coefficients for the various species at their respective absorption ... Glya Recorded by 1H-NMR Spectroscopy TABLE 2 Molar Extinction Coeff...

International Nuclear Information System (INIS)

Systematic analysis of the energy level schemes, ground state absorption (GSA) and covalency effects for the Ni"2"+ ion in Ca_3Sc_2Ge_3O_1_2 was performed. The recently developed first-principles approach to the analysis of the absorption spectra of impurity ions in crystals based on the discrete variational multi-electron method (DV-ME) [K. Ogasawara et al., Phys. Rev. B 64, 115413 (2001)] was used in the calculations. As a result, complete energy level schemes of Ni"2"+ and its absorption spectra at both possible crystallographic positions (distorted octahedral Sc"3"+ and tetrahedral Ge"4"+ positions) were calculated, assigned and compared with experimental data. Energies of the charge transfer (CT) transitions for both positions are estimated. Numerical contributions of all possible electron configurations into the calculated energy states were determined. By performing analysis of the molecular orbitals (MO) population, ...

Energy Technology Data Exchange (ETDEWEB)

Work continued on the correlations of catalytic activity of metals and surface structure. Work is described in the following areas: CO oxidation on a Cu/Rh(100) Bimetallic catalysts; electronic properties of bimetallic surfaces; and reflection absorption spectroscopy of bimetallic surfaces. 5 figs. (CBS)

International Nuclear Information System (INIS)

The bioavailability of lead was studied in rats fed various baby foods (Babymix-turkey, Babymix-vegetables, Frutolino-fruit, Frutamix-bananas, Babyron-S-26, Truefood), cow's milk, bread, liver and standard rat diet. Lead absorption was determined by measuring the whole body retention of "2"0"3Pb 6 days after a single oral application. Highest absorption values ranging from 17 to 20% were obtained in animals fed cow's milk and fruit foods. Rats on other human diets absorbed between 3 and 8% of the radioactive lead dose. Only in animals on rat diet lead absorption was below 1%. It is concluded that rats fed human diets show absorption values similar to those in humans. This might indicate that the bioavailability of lead is primarily dependent on dietary habits. This experimental model, if confirmed by further work, might be useful for obtaining preliminary data on the bioavailability of metals from ...

UK PubMed Central (United Kingdom)

Albendazole binds to parasite's tubulin inhibiting its glucose absorption. Its common adverse effects are nausea, vomiting, constipation, thirst, dizziness, headache, hair loss and pruritus. Although...Full Text Available

International Nuclear Information System (INIS)

It is answered to a previous letter by Basano, and shown that the difficulties met by that author within ''Extended relativity'' do not exist, but are due to the erroneous assumption that a certain condition for tachyons to be absorbed by a macro-object is sufficient (whilst it is only a necessary one).

Energy Technology Data Exchange (ETDEWEB)

Basic experimental investigations were carried out with an aqueous solution of a mixture of KOH and NaOH for use as an absorbent in absorption heat pumps. Due to its thermophysical properties this mixture allows temperature lifts from evaporator to absorber of more than 75 K (135 F) in a single-stage absorption chiller. Thermophysical and hydrodynamical properties of the solution were measured. Vapor-liquid-equilibrium data and specific heat capacities were determined for concentrations ranging from 35% up to 75% and temperatures up to 200 C (392 F). From these data the enthalpy of the solution was calculated. Additionally the crystallization temperatures, the density, and the viscosity of the solution were determined. The experimental equipment is described. The data are presented as polynomials and diagrams including experimental accuracy. An apparatus was constructed to measure heat and mass transfer coefficients of the ...

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

This device has and head-race pipe with an external part and a coaxial inner part. A measuring head is mounted movable between these 2 parts and has at least a thermocouple and a mobile grid for varying the section and the sodium flow to facilitate the impurities dissolution. This ensemble is completed by a longitudinal body containing the main parts of the indicator and surrounded by a thermal exchanger to cool the sodium.

Energy Technology Data Exchange (ETDEWEB)

A fuel injector comprises first and second housing parts, the first housing part being located within a bore or recess formed in the second housing part, the housing parts defining therebetween an inlet chamber, a delivery chamber axially spaced from the inlet chamber, and a filtration flow path interconnecting the inlet and delivery chambers to remove particulate contaminants from the flow of fuel therebetween.

KoreaScience (Korea)

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