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Sample records for emission spectroscopy phosphorus

  1. Extraction inductively coupled plasma-optical emission spectrometry (ICP-OES). Determination of traces of phosphorus in tungsten

    International Nuclear Information System (INIS)

    Bauer, G.; Wegscheider, W.; Mueller, K.

    1989-01-01

    A method for the separation and preconcentration of traces of phosphorus from tungsten was developed. Solid phase extraction of the phosphovanadomolybdate complex performed on a micro-column was applied. Phosphorus was determined by optical emission spectroscopy (OES) with inductively coupled plasma (ICP) excitation. A limit of detection of 0,4 μg/g P with respect to the solid phase is obtained. By directly coupling the extraction/elution step to the ICP instrument a detection limit of 0,06 μg/g P in W was achieved. Besides, the complexity of spectral evaluation in ICP-OES determinations of traces in spectralline-rich matrices is discussed. (Authors)

  2. Emission bands of phosphorus and calculation of band structure of rare earth phosphides

    International Nuclear Information System (INIS)

    Al'perovich, G.I.; Gusatinskij, A.N.; Geguzin, I.I.; Blokhin, M.A.; Torbov, V.I.; Chukalin, V.I.; AN SSSR, Moscow. Inst. Novykh Khimicheskikh Problem)

    1977-01-01

    The method of x-ray emission spectroscopy has been used to investigate the electronic structure of monophosphides of rare-earth metals (REM). The fluorescence K bands of phosphorus have been obtained in LaP, PrP, SmP, GdP, TbP, DyP, HoP, ErP, TmP, YbP, and LuP and also the Lsub(2,3) bands of phosphorus in ErP, TmP, YbP, and LuP. Using the Green function technique involving the muffin-tin potential, the energy spectrum for ErP has been calculated in the single-electron approximation. The hystogram of electronic state distribution N(E) is compared with the experimental K and Lsub(2,3) bands of phosphorus in ErP. The agreement between the main details of N(E) and that of x-ray spectra allows to state that the model used provides a good description of the electron density distribution in crystals of REM monophosphides. In accordance with the character of the N(E) distribution the compounds under study are classified as semimetals or semiconductors with a very narrow forbidden band

  3. One-pot and ultrafast synthesis of nitrogen and phosphorus co-doped carbon dots possessing bright dual wavelength fluorescence emission

    Science.gov (United States)

    Sun, Xiangcheng; Brückner, Christian; Lei, Yu

    2015-10-01

    Very brief microwave heating of aniline, ethylene diamine, and phosphoric acid in water at ambient pressure generated nitrogen and phosphorus co-doped carbon dots (N,P-CDs) that exhibit bright dual blue (centred at 450 nm; 51% quantum yield) and green (centred at 510 nm, 38% quantum yield) fluorescence emission bands. The N,P-CDs were characterized using TEM, XRD, XPS, IR, UV-vis, and fluorescence spectroscopy, demonstrating their partially crystalline carbon, partially amorphous structures, and the incorporation of O, N, and P into the carbogenic scaffold. The N,P-CDs demonstrated excitation-dependent and nearly pH-independent emission properties. The unique dual emission properties lay the foundation for the use of N,P-CDs in ratiometric sensing applications.Very brief microwave heating of aniline, ethylene diamine, and phosphoric acid in water at ambient pressure generated nitrogen and phosphorus co-doped carbon dots (N,P-CDs) that exhibit bright dual blue (centred at 450 nm; 51% quantum yield) and green (centred at 510 nm, 38% quantum yield) fluorescence emission bands. The N,P-CDs were characterized using TEM, XRD, XPS, IR, UV-vis, and fluorescence spectroscopy, demonstrating their partially crystalline carbon, partially amorphous structures, and the incorporation of O, N, and P into the carbogenic scaffold. The N,P-CDs demonstrated excitation-dependent and nearly pH-independent emission properties. The unique dual emission properties lay the foundation for the use of N,P-CDs in ratiometric sensing applications. Electronic supplementary information (ESI) available: Detailed experimental section, XRD, FTIR, explosive sensing and the applications results. See DOI: 10.1039/c5nr05549k

  4. Phosphorus-31 magnetic resonance spectroscopy of experimentally induced arthritis in rats

    International Nuclear Information System (INIS)

    Blatter, D.D.

    1987-01-01

    Phosphorus-31 magnetic resonance spectroscopy (MRS) of the hind paws of rats was performed at 1.5 Tesla before and during the course of an experimentally-induced inflammatory arthritis. Arthritis was induced by daily subcutaneous administration of 6-sulfanilamidoindazole, an antibacterial sulfa known to produce an acute, self-limited arthritis and periarthritis in the hind paws of rats. Phosphorus-31 spectra obtained after the development of clinical arthritis showed a significant (p 31 P MRS may permit evaluation of the severity of an inflammatory arthritis with greater accuracy than the bony changes definable by plain roentgenograms. (orig.)

  5. Near-Infrared Phosphorus-Substituted Rhodamine with Emission Wavelength above 700 nm for Bioimaging.

    Science.gov (United States)

    Chai, Xiaoyun; Cui, Xiaoyan; Wang, Baogang; Yang, Fan; Cai, Yi; Wu, Qiuye; Wang, Ting

    2015-11-16

    Phosphorus has been successfully fused into a classic rhodamine framework, in which it replaces the bridging oxygen atom to give a series of phosphorus-substituted rhodamines (PRs). Because of the electron-accepting properties of the phosphorus moiety, which is due to effective σ*-π* interactions and strengthened by the inductivity of phosphine oxide, PR exhibits extraordinary long-wavelength fluorescence emission, elongating to the region above 700 nm, with bathochromic shifts of 140 and 40 nm relative to rhodamine and silicon-substituted rhodamine, respectively. Other advantageous properties of the rhodamine family, including high molar extinction coefficient, considerable quantum efficiency, high water solubility, pH-independent emission, great tolerance to photobleaching, and low cytotoxicity, stay intact in PR. Given these excellent properties, PR is desirable for NIR-fluorescence imaging in vivo. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Surface modification by vacuum annealing for field emission from heavily phosphorus-doped homoepitaxial (1 1 1) diamond

    International Nuclear Information System (INIS)

    Yamada, Takatoshi; Nebel, Christoph E.; Somu, Kumaragurubaran; Shikata, Shin-ichi

    2008-01-01

    The relationship between field emission properties and C 1s core level shifts of heavily phosphorus-doped homoepitaxial (1 1 1) diamond is investigated as a function of annealing temperature in order to optimize surface carbon bonding configurations for device applications. A low field emission threshold voltage is observed from surfaces annealed at 800 deg. C for hydrogen-plasma treated surface, while a low field emission threshold voltage of wet-chemical oxidized surface is observed after annealing at 900 deg. C. The C 1s core level by X-ray photoelectron spectroscopy (XPS) showed a shoulder peak at 1 eV below the main peak over 800 and 900 deg. C annealing temperature for hydrogen-plasma treated and wet-chemical oxidized surfaces, respectively. When the shoulder peak intensity is less than 10% of the main peak intensity, lower threshold voltages are observed. This is due to the carbon-reconstruction which gives rise to a small positive electron affinity. By increasing annealing temperature, the shoulder peak ratios also increase, which indicates that a surface graphitization takes place. This leads to higher threshold voltages

  7. Few-layer black phosphorus nanoparticles.

    Science.gov (United States)

    Sofer, Zdenek; Bouša, Daniel; Luxa, Jan; Mazanek, Vlastimil; Pumera, Martin

    2016-01-28

    Herein, black phosphorus quantum dots and nanoparticles of a few layer thickness were prepared and characterized using STEM, AFM, dynamic light scattering, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy and photoluminescence. Impact electrochemistry of the induvidual black phosphorus nanoparticles allows their size determination. The centrifugation of colloidal black phosphorus nanoparticles allowed separation of quantum dots with sizes up to 15 nm. These black phosphorus nanoparticles exhibit a large band gap and are expected to find a wide range of applications from semiconductors to biomolecule tags. The use of black phosphorus nanoparticles for vapour sensing was successfully demonstrated.

  8. Effect of phosphorus incorporation on morphology and optical properties of ZnO nanorods

    International Nuclear Information System (INIS)

    Fan, Donghua; Zhang, Rong; Wang, Xianghu

    2011-01-01

    Graphical abstract: XPS spectra of the P-doped ZnO nanorods: (a) Zn 2p, (b) O 1s, and (c) P 2p spectra. The red curve in c is the Gauss-fitting curve. (d) Raman spectra of P-doped (curve 1) and pure (curve 2) ZnO nanorods. Research highlights: → P-doped ZnO nanorods have been prepared on Si substrates without any catalyst. → The introduction of phosphorus leads to the growth of tapered tip in the nanorods. → The formation of tapered tip is attributed to the relaxation of the lattice strain along the radial direction. → The strong ultraviolet peak is connected with the phosphorus acceptor-related emissions. -- Abstract: Phosphorus-doped ZnO nanorods have been prepared on Si substrates by thermal evaporation process without any catalyst. X-ray photoelectron spectroscopy and Raman spectra indicate that phosphorus entering into ZnO nanorods mainly occupies Zn site rather than O one. The introduction of phosphorus leads to the morphological changes of nanorods from hexagonal tip to tapered one, which should be attributed to the relaxation of the lattice strain caused by phosphorus occupying Zn site along the radial direction. Transmission electron microscopy shows that phosphorus-doped ZnO nanorods still are single crystal and grow along [0 0 0 1] direction. The effect of phosphorous dopant on optical properties of ZnO nanorods also is studied by the temperature-dependent photoluminescence spectra, which indicates that the strong ultraviolet emission is connected with the phosphorus acceptor-related emissions.

  9. Photoluminescence study of novel phosphorus-doped ZnO nanotetrapods synthesized by chemical vapour deposition

    International Nuclear Information System (INIS)

    Yu Dongqi; Hu Lizhong; Qiao Shuangshuang; Zhang Heqiu; Fu Qiang; Chen Xi; Sun Kaitong; Len, Song-En Andy; Len, L K

    2009-01-01

    Novel phosphorus-doped and undoped single crystal ZnO nanotetrapods were fabricated on sapphire by a simple chemical vapour deposition method, using phosphorus pentoxide (P 2 O 5 ) as the dopant source. The optical properties of the samples were investigated by photoluminescence (PL) spectroscopy. Low-temperature PL measurements of phosphorus-doped and undoped samples were compared, and the results indicated a decrease in deep level defects due to the incorporation of a phosphorus acceptor dopant. The PL spectrum of the phosphorus-doped sample at 10 K exhibited several acceptor-bound exciton related emission peaks. The effect of phosphorus doping on the optical characteristics of the samples was investigated by excitation intensity and temperature dependent PL spectra. The acceptor-binding energies of the phosphorus dopant were estimated to be about 120 meV, in good agreement with the corresponding theoretical and experimental values in phosphorus-doped ZnO films and nanowires.

  10. Characterization of phosphorus species in sediments from the Arabian Sea oxygen minimum zone: Combining sequential extractions and X-ray spectroscopy

    NARCIS (Netherlands)

    Kraal, Peter; Bostick, Benjamin C.; Behrends, Thilo; Reichart, Gert-Jan; Slomp, Caroline P.

    2015-01-01

    The bulk phosphorus (P) distribution in sediment samples from the oxygen minimum zone of the northern Arabian Sea was determined using two methods: sequential chemical extraction (the ‘SEDEX’ procedure) and X-ray absorption near-edge structure (XANES) spectroscopy of the phosphorus K-edge. Our

  11. Brain aging: Evaluation of pH using phosphorus magnetic resonance spectroscopy.

    Science.gov (United States)

    Cichocka, Monika; Kozub, Justyna; Urbanik, Andrzej

    2018-02-02

    Very important aspects of aging include age-related changes occurring in the brain. The aim of the present study was to identify the standard pH value in the entire brain volume using phosphorus magnetic resonance spectroscopy in healthy individuals of both sexes in different age groups, and then to determine whether there are differences in these values. A total of 65 individuals aged 20-32 years (mean age 24.5 ± 2.1 years, 31 women and 34 men) and 31 individuals aged 60-81 years (mean age 64.9 ± 5.5 years, 17 women and 14 men) were studied. The phosphorus magnetic resonance spectroscopy examination was carried out using a 1.5-T magnetic resonance system. The signal was acquired from the volume of interest that covered the whole brain. A vast majority of the examined individuals had slightly alkaline brain pH regardless of age. In the ≥20 years group, pH was 7.09 ± 0.11, and in the ≥60 years group, the average pH was 7.03 ± 0.05. This comparison of the pH identified in all the tested individuals shows a negative correlation of pH with age. The present findings might provide a valuable basis for further research into "healthy aging" as well as pathology in older adults. Geriatr Gerontol Int 2018; ••: ••-••. © 2018 Japan Geriatrics Society.

  12. Photon Activation Analysis Of Light Elements Using 'Non-Gamma' Radiation Spectroscopy - The Instrumental Determination Of Phosphorus

    International Nuclear Information System (INIS)

    Segebade, Christian; Goerner, Wolf

    2011-01-01

    Unlike metal determinations the analysis of light elements (e.g., carbon, oxygen, phosphorus) is frequently problematic, in particular if analysed instrumentally. In photon activation analysis (PAA) the respective activation products do not emit gamma radiation in the most cases. Usually, annihilation quanta counting and subsequent decay curve analysis have been used for determinations of C, N, O, and F. However, radiochemical separation of the respective radioisotopes mostly is indispensable. For several reasons, some of the light elements cannot be analysed following this procedure, e.g. phosphorus. In this contribution the instrumental PAA of phosphorus in organic matrix by activation with bremsstrahlung of an electron linear accelerator and subsequent beta spectroscopy is described. The accuracy of the results was excellent as obtained by analysis of a BCR Reference Material.

  13. 31phosphorus spectroscopy of space-occupying lesions of the salivary glands. Clinic results and differential diagnosis

    International Nuclear Information System (INIS)

    Vogl, T.J.; Dadashi, A.; Jassoy, A.; Becker, C.; Reimann, V.; Lissner, J.

    1993-01-01

    In a prospective study, 15 normals and 20 patients with space-occupying lesions of the salivary glands were examined by MRT images and by in vivo 31 phosphorus spectroscopy. The spectra of malignant tumours showed a significant increase in concentration of phosphomonoesters, phosphodiesters and inorganic phosphates when compared with normals. In addition there was an enormous reduction in creatine phosphates. Increased pH values and marked increase in concentration of inorganic phosphates correlated with poorly vascularised necrotic tumour segments. Concentrations of ATP and PCr were similar to normal muscle tissue. High concentrations of PME and PDE correlated directly with the proliferation of tumour cells and were an important marker for the bioenergy and phospholipid metabolism of the growing tumour. Standardised in vivo 31 phosphorus spectroscopy of space-occupying lesions of the salivary glands provides noninvasive prognostic information on the type and behaviour of the lesion and is complementary to clinical and histological findings. (orig.) [de

  14. Liquid-Arc/Spark-Excitation Atomic-Emission Spectroscopy

    Science.gov (United States)

    Schlagen, Kenneth J.

    1992-01-01

    Constituents of solutions identified in situ. Liquid-arc/spark-excitation atomic-emission spectroscopy (LAES) is experimental variant of atomic-emission spectroscopy in which electric arc or spark established in liquid and spectrum of light from arc or spark analyzed to identify chemical elements in liquid. Observations encourage development of LAES equipment for online monitoring of process streams in such industries as metal plating, electronics, and steel, and for online monitoring of streams affecting environment.

  15. Characterizing Exoplanet Habitability with Emission Spectroscopy

    Science.gov (United States)

    Robinson, Tyler

    2018-01-01

    Results from NASA’s Kepler mission and other recent exoplanet surveys have demonstrated that potentially habitable exoplanets are relatively common, especially in the case of low-mass stellar hosts. The next key question that must be addressed for such planets is whether or not these worlds are actually habitable, implying they could sustain surface liquid water. Only through investigations of the potential habitability of exoplanets and through searches for biosignatures from these planets will we be able to understand if the emergence of life is a common phenomenon in our galaxy. Emission spectroscopy for transiting exoplanets (sometimes called secondary eclipse spectroscopy) is a powerful technique that future missions will use to study the atmospheres and surfaces of worlds orbiting in the habitable zones of nearby, low-mass stars. Emission observations that span the mid-infrared wavelength range for potentially habitable exoplanets provide opportunities to detect key habitability and life signatures, and also allow observers to probe atmospheric and surface temperatures. This presentation will outline the case for using emission spectroscopy to understand if an exoplanet can sustain surface liquid water, which is believed to be a critical precursor to the origin of life.

  16. Transient Infrared Emission Spectroscopy

    Science.gov (United States)

    Jones, Roger W.; McClelland, John F.

    1989-12-01

    Transient Infrared Emission Spectroscopy (TIRES) is a new technique that reduces the occurrence of self-absorption in optically thick solid samples so that analytically useful emission spectra may be observed. Conventional emission spectroscopy, in which the sample is held at an elevated, uniform temperature, is practical only for optically thin samples. In thick samples the emission from deep layers of the material is partially absorbed by overlying layers.1 This self-absorption results in emission spectra from most optically thick samples that closely resemble black-body spectra. The characteristic discrete emission bands are severely truncated and altered in shape. TIRES bypasses this difficulty by using a laser to heat only an optically thin surface layer. The increased temperature of the layer is transient since the layer will rapidly cool and thicken by thermal diffusion; hence the emission collection must be correlated with the laser heating. TIRES may be done with both pulsed and cw lasers.2,3 When a pulsed laser is used, the spectrometer sampling must be synchronized with the laser pulsing so that only emission during and immediately after each laser pulse is observed.3 If a cw laser is used, the sample must move rapidly through the beam. The hot, transient layer is then in the beam track on the sample at and immediately behind the beam position, so the spectrometer field of view must be limited to this region near the beam position.2 How much self-absorption the observed emission suffers depends on how thick the heated layer has grown by thermal diffusion when the spectrometer samples the emission. Use of a pulsed laser synchronized with the spectrometer sampling readily permits reduction of the time available for heat diffusion to about 100 acs .3 When a cw laser is used, the heat-diffusion time is controlled by how small the spectrometer field of view is and by how rapidly the sample moves past within this field. Both a very small field of view and a

  17. 210Po and 210Pb emissions to air from the thermal phosphorus plant in Europe: measurements in the environment and dose assessment for regulatory purpose

    International Nuclear Information System (INIS)

    Tanzi, C.P.; Knetsch, G.J.

    2013-01-01

    In 1983 in The Netherlands, an environmental survey at a river estuary revealed elevated radionuclide concentrations above the background level. The source was identified as an industrial plant producing elemental phosphorus, by means of a thermal process. Within a few years a permit for emissions of radionuclides to the environment was requested under the prevailing Nuclear Energy Act, and granted. Since 1987 the industry reports its emission data to the mandated Ministry. This phosphorus plant contributes the highest release of 210 Po and 210 Pb to air in the Netherlands. The difficulty of identifying the enhanced activity due to the elemental phosphorus through environmental measurement is here illustrated by showing, by means of an air dispersion model, that the radioactivity added by the phosphorus plant to the environment is comparable to the natural background level. The estimate of the excess air concentration given exclusively by a continuous annual emission of 500 GBq, bound to aerosols of size less than 1 micron, varies from 450 to 750 micro Bq/m 3 at a distance of 3.5 km from the phosphorus plant, depending on yearly weather variations. This may be compared to the natural background level as it is measured at a distance of over 100 km inland from the phosphorus plant, at RIVM, the National Institute for Public Health and the Environment. The yearly average measured 210 Pb activity concentration in air is 363±5 micro Bq/m 3 in 2009 which is within range of other years. At the coastal site where the phosphorus plant is located, the natural background will be lower. The gross beta activity concentration near the phosphorus plant is 296 micro Bq/m 3 in 2009: this includes the emissions to air from the sintering process. The emission to air for the year 2009 reported by the phosphorus plan is 80 GBq/y of 210 Pb

  18. Overestimation of organic phosphorus in wetland soils by alkaline extraction and molybdate colorimetry.

    Science.gov (United States)

    Turner, Benjamin L; Newman, Susan; Reddy, K Ramesh

    2006-05-15

    Accurate information on the chemical nature of soil phosphorus is essential for understanding its bioavailability and fate in wetland ecosystems. Solution phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy was used to assess the conventional colorimetric procedure for phosphorus speciation in alkaline extracts of organic soils from the Florida Everglades. Molybdate colorimetry markedly overestimated organic phosphorus by between 30 and 54% compared to NMR spectroscopy. This was due in large part to the association of inorganic phosphate with organic matter, although the error was exacerbated in some samples by the presence of pyrophosphate, an inorganic polyphosphate that is not detected by colorimetry. The results have important implications for our understanding of phosphorus biogeochemistry in wetlands and suggest that alkaline extraction and solution 31p NMR spectroscopy is the only accurate method for quantifying organic phosphorus in wetland soils.

  19. The study of human organs by phosphorus-31 topical magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Oberhaensli, R.D.; Galloway, G.J.; Hilton-Jones, David; Bore, P.J.; Styles, Peter; Rajagopalan, Bheeshma; Taylor, D.J.; Radda, G.K.

    1987-01-01

    The potential clinical use of topical magnetic resonance spectroscopy (volume selection by static magnetic field gradients) was tested in 50 studies in volunteers. Topical magnetic resonance spectroscopy (MRS) was shown to be a straightforward method for localising 31 P spectra of brain and liver. However, the spherical shape and fixed position of the selected volume posed serious limitations to the study of heart and transplanted kidney by topical MRS. Phosphorus-31 spectra of approx. 30 cm -3 of brain or liver could be obtained in 8 min. Ratios of metabolite concentrations could be determined with a coefficient of variation ranging from 10% to 30%. The ratios of phosphocreatine/ATP and inorganic phosphate/ATP in brain were 1.8 and 0.3, respectively. The ratio of inorganic phosphate/ATP in liver was 0.9. Intracellular pH was 7.03 in brain and 7.24 in liver. The T 1 relaxation times of phosphocreatine, inorganic phosphate and γ-ATP in brain were 4.8 s, 2.5 s and 1.0 s, respectively. (author)

  20. Thermally emissive sensing materials for chemical spectroscopy analysis

    Science.gov (United States)

    Poole, Zsolt; Ohodnicki, Paul R.

    2018-05-08

    A sensor using thermally emissive materials for chemical spectroscopy analysis includes an emissive material, wherein the emissive material includes the thermally emissive materials which emit electromagnetic radiation, wherein the electromagnetic radiation is modified due to chemical composition in an environment; and a detector adapted to detect the electromagnetic radiation, wherein the electromagnetic radiation is indicative of the chemical interaction changes and hence chemical composition and/or chemical composition changes of the environment. The emissive material can be utilized with an optical fiber sensor, with the optical fiber sensor operating without the emissive material probed with a light source external to the material.

  1. Anthropogenic phosphorus flow analysis of Hefei City, China

    International Nuclear Information System (INIS)

    Li Sisi; Yuan Zengwei; Bi Jun; Wu Huijun

    2010-01-01

    The substance flow analysis (SFA) method was employed to examine phosphorus flow and its connection to water pollution in the city of Hefei, China, in 2008. As human activity is the driving force of phosphorus flux from the environment to the economy, the study provides a conceptual framework for analyzing an anthropogenic phosphorus cycle that includes four stages: extraction, fabrication and manufacturing, use, and waste management. Estimates of phosphorus flow were based on existing data as well as field research, expert advice, local accounting systems, and literature. The total phosphorus input into Hefei in 2008 reached 7810 tons, mainly as phosphate ore, chemical fertilizer, pesticides, crops and animal products. Approximately 33% of the total phosphorus input left the area, and nearly 20% of that amount was discharged as waste to surface water. Effluent containing excessive fertilizer from farming operations plays an important role in phosphorus overloads onto surface water; the other major emission source is sewage discharge. We also provide suggestions for reducing phosphorus emissions, for example reducing fertilizer use, recycling farming residues, and changing human consumption patterns.

  2. Determination of Serum Lithium by Flame Emission Spectroscopy

    Directory of Open Access Journals (Sweden)

    R. Nafissy

    1976-07-01

    Full Text Available Lithum can be de termined both by atomic absorption spectroscopy andflame emission spectroscopy. We have used the later method with a Zeiss Model pMQlI spectro photometer fitt ed with ante-chamber atomizer and a potensiome rric line recorder. Accurate ana lysis for the clement was acco mplished due to a sophisracared measuring instrument.

  3. Modeling diffuse phosphorus emissions to assist in best management practice designing

    Science.gov (United States)

    Kovacs, Adam; Zessner, Matthias; Honti, Mark; Clement, Adrienne

    2010-05-01

    A diffuse emission modeling tool has been developed, which is appropriate to support decision-making in watershed management. The PhosFate (Phosphorus Fate) tool allows planning best management practices (BMPs) in catchments and simulating their possible impacts on the phosphorus (P) loads. PhosFate is a simple fate model to calculate diffuse P emissions and their transport within a catchment. The model is a semi-empirical, catchment scale, distributed parameter and long-term (annual) average model. It has two main parts: (a) the emission and (b) the transport model. The main input data of the model are digital maps (elevation, soil types and landuse categories), statistical data (crop yields, animal numbers, fertilizer amounts and precipitation distribution) and point information (precipitation, meteorology, soil humus content, point source emissions and reservoir data). The emission model calculates the diffuse P emissions at their source. It computes the basic elements of the hydrology as well as the soil loss. The model determines the accumulated P surplus of the topsoil and distinguishes the dissolved and the particulate P forms. Emissions are calculated according to the different pathways (surface runoff, erosion and leaching). The main outputs are the spatial distribution (cell values) of the runoff components, the soil loss and the P emissions within the catchment. The transport model joins the independent cells based on the flow tree and it follows the further fate of emitted P from each cell to the catchment outlets. Surface runoff and P fluxes are accumulated along the tree and the field and in-stream retention of the particulate forms are computed. In case of base flow and subsurface P loads only the channel transport is taken into account due to the less known hydrogeological conditions. During the channel transport, point sources and reservoirs are also considered. Main results of the transport algorithm are the discharge, dissolved and sediment

  4. Steelmaking process control using remote ultraviolet atomic emission spectroscopy

    Science.gov (United States)

    Arnold, Samuel

    Steelmaking in North America is a multi-billion dollar industry that has faced tremendous economic and environmental pressure over the past few decades. Fierce competition has driven steel manufacturers to improve process efficiency through the development of real-time sensors to reduce operating costs. In particular, much attention has been focused on end point detection through furnace off gas analysis. Typically, off-gas analysis is done with extractive sampling and gas analyzers such as Non-dispersive Infrared Sensors (NDIR). Passive emission spectroscopy offers a more attractive approach to end point detection as the equipment can be setup remotely. Using high resolution UV spectroscopy and applying sophisticated emission line detection software, a correlation was observed between metal emissions and the process end point during field trials. This correlation indicates a relationship between the metal emissions and the status of a steelmaking melt which can be used to improve overall process efficiency.

  5. Anthropogenic phosphorus flow analysis of Hefei City, China.

    Science.gov (United States)

    Li, Sisi; Yuan, Zengwei; Bi, Jun; Wu, Huijun

    2010-11-01

    The substance flow analysis (SFA) method was employed to examine phosphorus flow and its connection to water pollution in the city of Hefei, China, in 2008. As human activity is the driving force of phosphorus flux from the environment to the economy, the study provides a conceptual framework for analyzing an anthropogenic phosphorus cycle that includes four stages: extraction, fabrication and manufacturing, use, and waste management. Estimates of phosphorus flow were based on existing data as well as field research, expert advice, local accounting systems, and literature. The total phosphorus input into Hefei in 2008 reached 7810 tons, mainly as phosphate ore, chemical fertilizer, pesticides, crops and animal products. Approximately 33% of the total phosphorus input left the area, and nearly 20% of that amount was discharged as waste to surface water. Effluent containing excessive fertilizer from farming operations plays an important role in phosphorus overloads onto surface water; the other major emission source is sewage discharge. We also provide suggestions for reducing phosphorus emissions, for example reducing fertilizer use, recycling farming residues, and changing human consumption patterns. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.

  6. Estimation of Phosphorus Emissions in the Upper Iguazu Basin (brazil) Using GIS and the More Model

    Science.gov (United States)

    Acosta Porras, E. A.; Kishi, R. T.; Fuchs, S.; Hilgert, S.

    2016-06-01

    Pollution emissions into the drainage basin have direct impact on surface water quality. These emissions result from human activities that turn into pollution loads when they reach the water bodies, as point or diffuse sources. Their pollution potential depends on the characteristics and quantity of the transported materials. The estimation of pollution loads can assist decision-making in basin management. Knowledge about the potential pollution sources allows for a prioritization of pollution control policies to achieve the desired water quality. Consequently, it helps avoiding problems such as eutrophication of water bodies. The focus of the research described in this study is related to phosphorus emissions into river basins. The study area is the upper Iguazu basin that lies in the northeast region of the State of Paraná, Brazil, covering about 2,965 km2 and around 4 million inhabitants live concentrated on just 16% of its area. The MoRE (Modeling of Regionalized Emissions) model was used to estimate phosphorus emissions. MoRE is a model that uses empirical approaches to model processes in analytical units, capable of using spatially distributed parameters, covering both, emissions from point sources as well as non-point sources. In order to model the processes, the basin was divided into 152 analytical units with an average size of 20 km2. Available data was organized in a GIS environment. Using e.g. layers of precipitation, the Digital Terrain Model from a 1:10000 scale map as well as soils and land cover, which were derived from remote sensing imagery. Further data is used, such as point pollution discharges and statistical socio-economic data. The model shows that one of the main pollution sources in the upper Iguazu basin is the domestic sewage that enters the river as point source (effluents of treatment stations) and/or as diffuse pollution, caused by failures of sanitary sewer systems or clandestine sewer discharges, accounting for about 56% of the

  7. ESTIMATION OF PHOSPHORUS EMISSIONS IN THE UPPER IGUAZU BASIN (BRAZIL USING GIS AND THE MORE MODEL

    Directory of Open Access Journals (Sweden)

    E. A. Acosta Porras

    2016-06-01

    Full Text Available Pollution emissions into the drainage basin have direct impact on surface water quality. These emissions result from human activities that turn into pollution loads when they reach the water bodies, as point or diffuse sources. Their pollution potential depends on the characteristics and quantity of the transported materials. The estimation of pollution loads can assist decision-making in basin management. Knowledge about the potential pollution sources allows for a prioritization of pollution control policies to achieve the desired water quality. Consequently, it helps avoiding problems such as eutrophication of water bodies. The focus of the research described in this study is related to phosphorus emissions into river basins. The study area is the upper Iguazu basin that lies in the northeast region of the State of Paraná, Brazil, covering about 2,965 km2 and around 4 million inhabitants live concentrated on just 16% of its area. The MoRE (Modeling of Regionalized Emissions model was used to estimate phosphorus emissions. MoRE is a model that uses empirical approaches to model processes in analytical units, capable of using spatially distributed parameters, covering both, emissions from point sources as well as non-point sources. In order to model the processes, the basin was divided into 152 analytical units with an average size of 20 km2. Available data was organized in a GIS environment. Using e.g. layers of precipitation, the Digital Terrain Model from a 1:10000 scale map as well as soils and land cover, which were derived from remote sensing imagery. Further data is used, such as point pollution discharges and statistical socio-economic data. The model shows that one of the main pollution sources in the upper Iguazu basin is the domestic sewage that enters the river as point source (effluents of treatment stations and/or as diffuse pollution, caused by failures of sanitary sewer systems or clandestine sewer discharges, accounting for

  8. Phosphorus acceptor doped ZnO nanowires prepared by pulsed-laser deposition

    International Nuclear Information System (INIS)

    Cao, B Q; Lorenz, M; Rahm, A; Wenckstern, H von; Czekalla, C; Lenzner, J; Benndorf, G; Grundmann, M

    2007-01-01

    Phosphorus-doped ZnO (ZnO:P) nanowires were successfully prepared by a novel high-pressure pulsed-laser deposition process using phosphorus pentoxide as the dopant source. Detailed cathodoluminescence studies of single ZnO:P nanowires revealed characteristic phosphorus acceptor-related peaks: neutral acceptor-bound exciton emission (A 0 , X, 3.356 eV), free-to-neutral-acceptor emission (e, A 0 , 3.314 eV), and donor-to-acceptor pair emission (DAP, ∼3.24 and ∼3.04 eV). This means that stable acceptor levels with a binding energy of about 122 meV have been induced in the nanowires by phosphorus doping. Moreover, the induced acceptors are distributed homogeneously along the doped nanowires

  9. Dynamic 31phosphorus magnetic resonance spectroscopy of the quadriceps muscle: Metabolic changes resulting from two different forms of exercise

    International Nuclear Information System (INIS)

    Schunk, K.; Kersjes, W.; Schadmand-Fischer, S.; Thelen, M.

    1997-01-01

    Purpose: The aim of the present investigation was to examine the metabolism of the quadriceps muscles of normal young individuals using dynamic 31 phosphorus magnetic resonance spectroscopy. Methods: 22 normal individuals were examined in a 1.5 T-MRT using a 6 cm surface coil. The metabolic changes in the quadriceps muscle as shown by the phosphorus spectrum were evaluated during rest, exercise (isometric and isotonic exercise) and during a 36-second period of recovery. Results: The P i /PCr quotient rose from its resting value of 0.11±0.02 following exercise to a maximum of 0.83±0.47 (isometric) or 1.40±0.59 (isotonic) (difference p=0.0001). Half-time recovery of P i /PCr was 35±11 s or 31±10 s, respectively (p=0.13). During the recovery phase P i /PCr fell briefly but significantly below its rest value. Following an initial rise in pH, there was a continual fall. Minimum pH (6.68±0.21 and 6.53±0.27 respectively; p=0.01) occurred in the early recovery phase. The recovery process of pH values lasted longer following isotonic than after isometric exercise (half-value recovery time 229±72 s and 146±55 s, respectively; p=0.001). Conlcusion: Compared with isometric exercise, isotonic stress is more expensive in terms of metabolism. Dynamic 31 phosphorus MRT spectroscopy can differentiate changes in muscle metabolism during different forms of exercise. (orig.) [de

  10. High-Resolution X-ray Emission and X-ray Absorption Spectroscopy

    NARCIS (Netherlands)

    Groot, F.M.F. de

    2000-01-01

    In this review, high-resolution X-ray emission and X-ray absorption spectroscopy will be discussed. The focus is on the 3d transition-metal systems. To understand high-resolution X-ray emission and reso-nant X-ray emission, it is first necessary to spend some time discussing the X-ray absorption

  11. Stability of passive films on amorphous Fe-Cr alloys with boron and phosphorus with impedance spectroscopy

    International Nuclear Information System (INIS)

    Virtanen, S.; Elsener, B.; Boehni, H.

    1989-01-01

    The mechanism of the passivation and the effect of metalloids on the stability of the passive films of amorphous Fe-Cr-(B,P,C) alloys has been investigated by polarization measurements, impedance spectroscopy and potential decay measurements. The results show that phosphorus facilitates the active/passive-transition by forming a porous iron-phosphate pre-passive layer on the alloy surface in the active range of the dissolution. This layer blocks the active sites of the surface and accelerates the cathodic H 2 -evolution reaction. The formation of the passivating chromium oxide layer takes place in the pores of this layer. In the passive range of the alloys oxidized phosphorus gets incorporated in the outer layer of the passive film. The presence of oxidized phosphorus as PO 4 3- anions in the passive film increases the localized corrosion resistance in Cl-containing solutions. The effect of the incorporated phosphates in the passive film is discussed with respect to the bipolar fixed-charge induced passivity model. The phosphates make the outer layer of the passive film cation-selective and thus hinder the penetration of the chlorides into the film. The oxidized boron species cannot change the ion-selectivity of the film; instead of this they negatively affect the stability of the passive film. (author) 18 refs., 9 figs., 3 tabs

  12. Process control with optical emission spectroscopy in triode ion plating

    International Nuclear Information System (INIS)

    Salmenoja, K.; Korhonen, A.S.; Sulonen, M.S.

    1985-01-01

    Physical vapor deposition (PVD) techniques used to prepare, e.g., hard TiN, HfN, or ZrN coatings include a great variety of processes ranging from reactive evaporation to sputtering and ion plating. In ion plating one effective way to enhance ionization is to use a negatively biased hot filament. The use of an electron emitting filament brings an extra variable to be taken into account in developing the process control. In addition, proper control of the evaporation source is critical in ensuring reproducible results. With optical emission spectroscopy (OES) it should be possible to control the coating process more accurately. The stoichiometry and the composition of the growing coating may then be ensured effectively in subsequent runs. In this work the application of optical emission spectroscopy for process control in triode ion plating is discussed. The composition of the growing coating is determined experimentally using the relative intensities of specific emission lines. Changes in the evaporation rate and the gas flow can be seen directly from emission line intensities. Even the so-called poisoning of the evaporation source with reactive gas can be detected. Several experimental runs were carried out and afterwards the concentration profiles of the deposited coatings were checked with the nuclear resonance broadening (NRB) method. The results show the usefulness of emission spectroscopy in discharge control

  13. New methods and applications in emission spectroscopy (1960); Methodes et applications nouvelles en spectroscopie d'emission (1960)

    Energy Technology Data Exchange (ETDEWEB)

    Baudin, G [Commissariat a l' Energie Atomique, Grenoble (France).Centre d' Etudes Nucleaires

    1960-07-01

    Emission spectroscopy, are already well-established instrumental analytical technique, has in recent years known important developments. Two mains factors are responsible; firstly the demands of metallurgy for purer and purer materials or alloys which are increasingly complex and difficult to analyse by chemical means; secondly, progress in optics, especially in the production of gratings, and in electronics in the field of photomultiplier tubes. We will not here catalogue all the new applications and methods, but we will consider a few amongst the most representative outside the conventional field. (author) [French] La spectroscopie d'emission, technique analytique instrumentale deja ancienne, a pris, depuis quelques annees, une extension notable. Deux facteurs principaux ont contribue a ce succes: d'une part, l'exigence de la metallurgie en materiaux de plus en plus pur ou en alliages de plus en plus complexes, difficiles a analyser chimiquement, d'autre part, les progres realises en optique, principalement dans la fabrication des reseaux, et en electronique dans le domaine des tubes photomultiplicateurs. Nous ne ferons pas ici le recensement de toutes les applications ou methodes nouvelles, mais nous en choisirons quelques unes des plus representatives hors du domaine classique. (auteur)

  14. Emission spectroscopy analysis during Nopal cladodes dethorning by laser ablation

    Science.gov (United States)

    Peña-Díaz, M.; Ponce, L.; Arronte, M.; Flores, T.

    2007-04-01

    Optical emission spectroscopy of the pulsed laser ablation of spines and glochids from Opuntia (Nopal) cladodes was performed. Nopal cladodes were irradiated with Nd:YAG free-running laser pulses on their body, glochids and spines. Emission spectroscopy analyses in the 350-1000 nm region of the laser induced plasma were made. Plasma plume evolution characterization, theoretical calculations of plasma plume temperature and experiments varying the processing atmosphere showed that the process is dominated by a thermally activated combustion reaction which increases the dethorning process efficiency. Therefore, appropriate laser pulse energy for minimal damage of cladodes body and in the area beneath glochids and spines can be obtained.

  15. Emission spectroscopy analysis during Nopal cladodes dethorning by laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Pena-Diaz, M; Ponce, L; Arronte, M; Flores, T [Laboratorio TecnologIa Laser, CICATA-IPN, Unidad Altamira, Carretera Tampico-Puerto Ind. Altamira, 89600, TAMPS (Mexico)

    2007-04-15

    Optical emission spectroscopy of the pulsed laser ablation of spines and glochids from Opuntia (Nopal) cladodes was performed. Nopal cladodes were irradiated with Nd:YAG free-running laser pulses on their body, glochids and spines. Emission spectroscopy analyses in the 350-1000 nm region of the laser induced plasma were made. Plasma plume evolution characterization, theoretical calculations of plasma plume temperature and experiments varying the processing atmosphere showed that the process is dominated by a thermally activated combustion reaction which increases the dethorning process efficiency. Therefore, appropriate laser pulse energy for minimal damage of cladodes body and in the area beneath glochids and spines can be obtained.

  16. Emission spectroscopy analysis during Nopal cladodes dethorning by laser ablation

    International Nuclear Information System (INIS)

    Pena-Diaz, M; Ponce, L; Arronte, M; Flores, T

    2007-01-01

    Optical emission spectroscopy of the pulsed laser ablation of spines and glochids from Opuntia (Nopal) cladodes was performed. Nopal cladodes were irradiated with Nd:YAG free-running laser pulses on their body, glochids and spines. Emission spectroscopy analyses in the 350-1000 nm region of the laser induced plasma were made. Plasma plume evolution characterization, theoretical calculations of plasma plume temperature and experiments varying the processing atmosphere showed that the process is dominated by a thermally activated combustion reaction which increases the dethorning process efficiency. Therefore, appropriate laser pulse energy for minimal damage of cladodes body and in the area beneath glochids and spines can be obtained

  17. X-ray photoelectron spectroscopy study of the functionalization of carbon metal-containing nanotubes with phosphorus atoms

    International Nuclear Information System (INIS)

    Shabanova, I.N.; Terebova, N.S.

    2013-01-01

    Highlights: •Carbon metal-containing nanotubes (Me–Cu, Ni, Fe) were functionalized with chemical groups containing different concentrations of phosphorous. •The C1s and Me3s spectra were measured by the X-ray photoelectron spectroscopy method. •The values of the atomic magnetic moment of the carbon metal-containing nanotubes were determined. -- Abstract: In the present paper, carbon metal-containing (Me: Cu, Ni, Fe) nanotubes functionalized with phosphorus atoms (ammonium polyphosphate) were studied by X-ray photoelectron spectroscopy (XPS) on an X-ray electron magnetic spectrometer. It is found that the functionalization leads to the change of the metal atomic magnetic moment, i.e. the value of the atomic magnetic moment in the functionalized carbon metal-containing (Cu, Ni, Fe) nanotubes increases and is higher than that in pristine nanotubes. It is shown that the covalent bond of Me and P atoms is formed. This leads to an increase in the activity of the nanostructure surface which is necessary for the modification of materials

  18. Erratum: Back reaction, emission spectrum and entropy spectroscopy

    Science.gov (United States)

    Jiang, Qing-Quan; Cai, Xu

    2012-06-01

    In our paper [Qing-Quan Jiang and Xu Cai, Back reaction, emission spectrum and entropy spectroscopy, JHEP 11 (2010) 066], there was an error in using the first law of black hole thermodynamic and the Bohr-Sommerfeld quantization rule. In this erratum, we attempt to rectify them.

  19. SU-F-J-46: Feasibility of Cerenkov Emission for Absorption Spectroscopy

    International Nuclear Information System (INIS)

    Oraiqat, I; Rehemtulla, A; Lam, K; Ten Haken, R; El Naqa, I; Clarke, R

    2016-01-01

    Purpose: Cerenkov emission (CE) is a promising tool for online tumor microenvironment interrogation and targeting during radiotherapy. In this work, we utilize CE generated during radiotherapy as a broadband excitation source for real-time absorption spectroscopy. We demonstrate the feasibility of CE spectroscopy using a controlled experiment of materials with known emission/absorption properties. Methods: A water tank is irradiated with 20 MeV electron beam to induce Cerenkov emission. Food coloring dyes (Yellow #5, Red #40, and Blue #1), which have known emission/absorption properties were added to the water tank with increasing concentration (1 drop (0.05 mL), 2 drops, and 4 drops from a dispenser bottle). The signal is collected using a condensing lens which is coupled into a 20m optical fiber that is fed into a spectrometer that measures the emitted spectra. The resulting spectra from water/food coloring dye solutions were normalized by the reference spectrum, which is the Cerenkov spectrum of pure water, correcting for both the nonlinearity of the broadband Cerenkov emission spectrum as well as the non-uniform spectral response of the spectrometer. The emitted spectra were then converted into absorbance and their characteristics were analyzed. Results: The food coloring dye had a drastic change on the Cerenkov emission, shifting its wavelength according to its visible color. The collected spectra showed various absorbance peaks which agrees with tabulated peak positions of the dyes added within 0.3% for yellow, 1.7% for red, and 0.16% for blue. The CE peak heights proportionally increased as the dye concentration is increased. Conclusion: This work shows the potential for real-time functional spectroscopy using Cerenkov emission during radiotherapy. It was demonstrated that molecule identification as well as relative concentration can be extracted from the Cerenkov emission color shift.

  20. SU-F-J-46: Feasibility of Cerenkov Emission for Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Oraiqat, I; Rehemtulla, A; Lam, K; Ten Haken, R; El Naqa, I [University of Michigan, Radiation Oncology, Ann Arbor, MI (United States); Clarke, R [University of Michigan, Physics Department, Ann Arbor, MI (United States)

    2016-06-15

    Purpose: Cerenkov emission (CE) is a promising tool for online tumor microenvironment interrogation and targeting during radiotherapy. In this work, we utilize CE generated during radiotherapy as a broadband excitation source for real-time absorption spectroscopy. We demonstrate the feasibility of CE spectroscopy using a controlled experiment of materials with known emission/absorption properties. Methods: A water tank is irradiated with 20 MeV electron beam to induce Cerenkov emission. Food coloring dyes (Yellow #5, Red #40, and Blue #1), which have known emission/absorption properties were added to the water tank with increasing concentration (1 drop (0.05 mL), 2 drops, and 4 drops from a dispenser bottle). The signal is collected using a condensing lens which is coupled into a 20m optical fiber that is fed into a spectrometer that measures the emitted spectra. The resulting spectra from water/food coloring dye solutions were normalized by the reference spectrum, which is the Cerenkov spectrum of pure water, correcting for both the nonlinearity of the broadband Cerenkov emission spectrum as well as the non-uniform spectral response of the spectrometer. The emitted spectra were then converted into absorbance and their characteristics were analyzed. Results: The food coloring dye had a drastic change on the Cerenkov emission, shifting its wavelength according to its visible color. The collected spectra showed various absorbance peaks which agrees with tabulated peak positions of the dyes added within 0.3% for yellow, 1.7% for red, and 0.16% for blue. The CE peak heights proportionally increased as the dye concentration is increased. Conclusion: This work shows the potential for real-time functional spectroscopy using Cerenkov emission during radiotherapy. It was demonstrated that molecule identification as well as relative concentration can be extracted from the Cerenkov emission color shift.

  1. Estimating and mapping grass phosphorus concentration in an African savanna using hyperspectral image data

    NARCIS (Netherlands)

    Mutanga, O.; Kumar, L.

    2007-01-01

    We tested the utility of imaging spectroscopy and neural networks to map phosphorus concentration in savanna grass using airborne HyMAP image data. We also sought to ascertain the key wavelengths for phosphorus prediction using hyperspectral remote sensing. The remote sensing of foliar phosphorus

  2. Phosphorus magnetic resonance spectroscopy in malformations of cortical development

    Directory of Open Access Journals (Sweden)

    Celi Santos Andrade

    2013-07-01

    Full Text Available Introduction Malformations of cortical development (MCD result from disruptions in the dynamic process of cerebral corticogenesis and are important causes of epilepsy, motor deficits and cognitive impairment. Objectives The aim of this study was to evaluate phospholipids metabolism in vivo in a series of patients with epilepsy and MCD. Methods Thirty-seven patients with MCD and 31 control subjects were studied using three-dimensional phosphorus magnetic resonance spectroscopy (31P-MRS at a 3.0 T scanner. Quantification methods were applied to the following resonances: phosphoethanolamine (PE, phosphocholine (PC, glycerophosphoethanolamine (GPE, glycerophosphocholine (GPC, inorganic phosphate (Pi, phosphocreatine (PCr, and a-, b-, and g-adenosine triphosphate (ATP. The magnesium (Mg2+ levels and pH were calculated based on PCr, Pi and b-ATP chemical shifts. Results Compared to controls, the MCD lesions exhibited lower pH values and higher Mg2+ levels (p<0.05. The lesions also presented significant reduction of GPC and PDE, and an increased PME/PDE ratio. The otherwise normal appearing parenchyma also demonstrated lower pH values in the frontoparietal cortex and bilateral centrum semiovale. Conclusions Our data support the idea that metabolic impairments occur in the lesions of MCD, with propagation to remote normal appearing parenchyma. The results also suggest that there are membrane turnover disturbances in MCD lesions.

  3. Stimulated X-Ray Emission Spectroscopy in Transition Metal Complexes

    Science.gov (United States)

    Kroll, Thomas; Weninger, Clemens; Alonso-Mori, Roberto; Sokaras, Dimosthenis; Zhu, Diling; Mercadier, Laurent; Majety, Vinay P.; Marinelli, Agostino; Lutman, Alberto; Guetg, Marc W.; Decker, Franz-Josef; Boutet, Sébastien; Aquila, Andy; Koglin, Jason; Koralek, Jake; DePonte, Daniel P.; Kern, Jan; Fuller, Franklin D.; Pastor, Ernest; Fransson, Thomas; Zhang, Yu; Yano, Junko; Yachandra, Vittal K.; Rohringer, Nina; Bergmann, Uwe

    2018-03-01

    We report the observation and analysis of the gain curve of amplified K α x-ray emission from solutions of Mn(II) and Mn(VII) complexes using an x-ray free electron laser to create the 1 s core-hole population inversion. We find spectra at amplification levels extending over 4 orders of magnitude until saturation. We observe bandwidths below the Mn 1 s core-hole lifetime broadening in the onset of the stimulated emission. In the exponential amplification regime the resolution corrected spectral width of ˜1.7 eV FWHM is constant over 3 orders of magnitude, pointing to the buildup of transform limited pulses of ˜1 fs duration. Driving the amplification into saturation leads to broadening and a shift of the line. Importantly, the chemical sensitivity of the stimulated x-ray emission to the Mn oxidation state is preserved at power densities of ˜1020 W /cm2 for the incoming x-ray pulses. Differences in signal sensitivity and spectral information compared to conventional (spontaneous) x-ray emission spectroscopy are discussed. Our findings build a baseline for nonlinear x-ray spectroscopy for a wide range of transition metal complexes in inorganic chemistry, catalysis, and materials science.

  4. External costs of cadmium emissions to soil: a drawback of phosphorus fertilizers

    DEFF Research Database (Denmark)

    Pizzol, Massimo; C.R. Smart, James; Thomsen, Marianne

    2014-01-01

    are exposed to cadmium through their diet causing potential adverse health impacts. Future scenarios for cadmium emissions to soil via agricultural applications of inorganic and organic fertilizers in Denmark were defined. A simplified fate and speciation model allowed the increase in soil cadmium......Abstract: In this study the Impact-Pathway Approach methodology was applied for monetary valuation of health impacts due to cadmium emitted to soil as a micro-pollutant present in phosphorus fertilizers. Due to the high persistency of cadmium in soil, and high soil-to-plant transfer rates, humans...... ammonium phosphate) and mineral fertilizer produced the lowest external health costs, followed by the fertilizer products wastewater sludge and pig manure. The external cost estimates produced in this study could be used to design economic policy instruments to encourage use of cleaner fertilizer products....

  5. Emission Line Imaging and Spectroscopy of Distant Galaxies

    DEFF Research Database (Denmark)

    Zabl, Johannes Florian

    for the gas surrounding a galaxy. Around some objects the extended Ly αemission is so strong that it can be detected for individual objects. In this thesis extremely deep VLT/XSHOOTER rest-frame far-UV spectroscopy is presented for Himiko, a gigantic Ly α emitter at redshift z = 6.6 or a time when...

  6. Photon emission spectroscopy of ion-atom collisions

    International Nuclear Information System (INIS)

    Nystroem, B.

    1995-10-01

    Emission cross sections for the 1snp 1 P 1 -levels have been measured by photon emission spectroscopy for the collision systems He + + He at 10 keV and He 2+ + He at 10-35 keV. Photon spectra of Krypton (Kr VIII) and Xenon (Xe V - IX) have also been obtained using 10q keV beams of Kr q+ (q=7-9) and Xe q+ (q=5-9) colliding with Helium and Argon. The Lifetimes of 3p 2 P-levels in Na-like Nb are reported together with lifetime for the 3s3p 3 P 1 -level in Mg-like Ni, Kr, Y, Zr and Nb where this level has an intercombination transition to the ground state. 45 refs, 20 figs

  7. 15N-urea tracing emission spectroscopy for detecting the infection of Helicobacter pylori

    International Nuclear Information System (INIS)

    Zhu Yayi

    2002-01-01

    Objective: To study a noninvasive and nonradioactive method, 15 N-urea tracing emission spectroscopy, for detecting the Helicobacter pylori (Hp) infection. Methods: A group of 26 patients was tested with a method of 15 N-urea tracing emission spectroscopy for detecting the Hp infection. Results: Taking the bacterial culture or (and) Gram stain as a standard, the specificity, sensitivity and positive predicting rate of the test were 81%, 89% and 84%, respectively. Conclusion: The method could be considered useful for clinical practice

  8. The Application of Moessbauer Emission Spectroscopy to Industrial Cobalt Based Fischer-Tropsch Catalysts

    International Nuclear Information System (INIS)

    Loosdrecht, J. van de; Berge, P. J. van; Craje, M. W. J.; Kraan, A. M. van der

    2002-01-01

    The application of Moessbauer emission spectroscopy to study cobalt based Fischer-Tropsch catalysts for the gas-to-liquids process was investigated. It was shown that Moessbauer emission spectroscopy could be used to study the oxidation of cobalt as a deactivation mechanism of high loading cobalt based Fischer-Tropsch catalysts. Oxidation was observed under conditions that are in contradiction with the bulk cobalt phase thermodynamics. This can be explained by oxidation of small cobalt crystallites or by surface oxidation. The formation of re-reducible Co 3+ species was observed as well as the formation of irreducible Co 3+ and Co 2+ species that interact strongly with the alumina support. The formation of the different cobalt species depends on the oxidation conditions. Iron was used as a probe nuclide to investigate the cobalt catalyst preparation procedure. A high-pressure Moessbauer emission spectroscopy cell was designed and constructed, which creates the opportunity to study cobalt based Fischer-Tropsch catalysts under realistic synthesis conditions.

  9. Hard X-ray emission spectroscopy with pink beam

    Energy Technology Data Exchange (ETDEWEB)

    Kvashnina, Kristina O.; Rossberg, Andre; Exner, Joerg; Scheinost, Andreas C. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Molecular Structures

    2017-06-01

    Valence-band X-ray emission spectroscopy (XES) with a ''pink beam'', i.e. a beam with large energy bandwidth produced by a double-multilayer monochromator, is introduced here to overcome the weak count rate of monochromatic beams produced by conventional double-crystal monochromators. Our results demonstrate that - in spite of the large bandwidth in the order of 100 eV - the high spectral resolution of the Johann-type spectrometer is maintained, while the two orders of magnitude higher flux greatly reduces the required counting time. The short working distance Johann-type X-ray emission spectrometer and multilayer monochromator is available at ROBL.

  10. Absorption spectrum of neutral phosphorus (P I) in the range 7700-8256 A

    International Nuclear Information System (INIS)

    Deng Lunhua; Li Chuanliang; Zhang Junli; Yang Xiaohua; Chen Yangqin

    2010-01-01

    The absorption spectrum of neutral phosphorus was recorded in the range 7700-8256 A using optical heterodyne magnetic rotation concentration modulation spectroscopy with a tunable Ti:sapphire laser as the light source. Phosphorus atoms were excited by discharging the mixed gases of phosphorus vapor and neon gas. The phosphorus vapor was prepared by heating white phosphorus chips placed on a cylindrical copper electrode during discharge. In total, 234 lines of P I were observed, of which 127 were assigned. The transition frequencies were obtained with an uncertainty of 0.007 cm -1 . Empirical line intensities were provided covering four orders of magnitude.

  11. Absorption spectrum of neutral phosphorus (P I) in the range 7700-8256 Å

    Science.gov (United States)

    Deng, Lunhua; Li, Chuanliang; Zhang, Junli; Yang, Xiaohua; Chen, Yangqin

    2010-12-01

    The absorption spectrum of neutral phosphorus was recorded in the range 7700-8256 Å using optical heterodyne magnetic rotation concentration modulation spectroscopy with a tunable Ti:sapphire laser as the light source. Phosphorus atoms were excited by discharging the mixed gases of phosphorus vapor and neon gas. The phosphorus vapor was prepared by heating white phosphorus chips placed on a cylindrical copper electrode during discharge. In total, 234 lines of P I were observed, of which 127 were assigned. The transition frequencies were obtained with an uncertainty of 0.007 cm-1. Empirical line intensities were provided covering four orders of magnitude.

  12. Enhanced visible light photocatalytic degradation of Rhodamine B over phosphorus doped graphitic carbon nitride

    Energy Technology Data Exchange (ETDEWEB)

    Chai, Bo, E-mail: willycb@163.com; Yan, Juntao; Wang, Chunlei; Ren, Zhandong; Zhu, Yuchan

    2017-01-01

    Highlights: • The phosphorus doped g-C{sub 3}N{sub 4} photocatalysts are synthesized by a co-pyrolysis procedure. • The crystal phase, morphology, and optical property of P doped g-C{sub 3}N{sub 4} are characterized. • The P doped g-C{sub 3}N{sub 4} photocatalysts show the improved photocatalytic activity. • The possible mechanism for enhanced photocatalytic activity is proposed. - Abstract: Phosphorus doped graphitic carbon nitride (g-C{sub 3}N{sub 4}) was easily synthesized using ammonium hexafluorophosphate (NH{sub 4}PF{sub 6}) as phosphorus source, and ammonium thiocyanate (NH{sub 4}SCN) as g-C{sub 3}N{sub 4} precursor, through a direct thermal co-polycondensation procedure. The obtained phosphorus doped g-C{sub 3}N{sub 4} was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectra (FTIR), UV–vis diffuse reflectance absorption spectra (UV-DRS), photoelectrochemical measurement and photoluminescence spectra (PL). The photocatalytic activities of phosphorus doped g-C{sub 3}N{sub 4} samples were evaluated by degradation of Rhodamine B (RhB) solution under visible light irradiation. The results showed that the phosphorus doped g-C{sub 3}N{sub 4} had a superior photocatalytic activity than that of pristine g-C{sub 3}N{sub 4}, attributing to the phosphorus atoms substituting carbon atoms of g-C{sub 3}N{sub 4} frameworks to result in light harvesting enhancement and delocalized π-conjugated system of this copolymer, beneficial for the increase of photocatalytic performance. The photoelectrochemical measurements also verified that the charge carrier separation efficiency was promoted by phosphorus doping g-C{sub 3}N{sub 4}. Moreover, the tests of radical scavengers demonstrated that the holes (h{sup +}) and superoxide radicals (·O{sub 2}{sup −}) were the main active species for the

  13. Photon emission spectroscopy of ion-atom collisions

    Energy Technology Data Exchange (ETDEWEB)

    Nystroem, B

    1995-10-01

    Emission cross sections for the 1snp{sup 1}P{sub 1}-levels have been measured by photon emission spectroscopy for the collision systems He{sup +} + He at 10 keV and He{sup 2+} + He at 10-35 keV. Photon spectra of Krypton (Kr VIII) and Xenon (Xe V - IX) have also been obtained using 10q keV beams of Kr{sup q+} (q=7-9) and Xe{sup q+} (q=5-9) colliding with Helium and Argon. The Lifetimes of 3p{sup 2}P-levels in Na-like Nb are reported together with lifetime for the 3s3p{sup 3}P{sub 1}-level in Mg-like Ni, Kr, Y, Zr and Nb where this level has an intercombination transition to the ground state. 45 refs, 20 figs.

  14. Phosphorus dendrimers and photodynamic therapy. Spectroscopic studies on two dendrimer-photosensitizer complexes: Cationic phosphorus dendrimer with rose bengal and anionic phosphorus dendrimer with methylene blue.

    Science.gov (United States)

    Dabrzalska, Monika; Zablocka, Maria; Mignani, Serge; Majoral, Jean Pierre; Klajnert-Maculewicz, Barbara

    2015-08-15

    Dendrimers due to their unique architecture may play an important role in drug delivery systems including chemotherapy, gene therapy and recently, photodynamic therapy as well. We investigated two dendrimer-photosensitizer systems in context of potential use of these systems in photodynamic therapy. The mixtures of an anionic phosphorus dendrimer of the second generation and methylene blue were studied by UV-vis spectroscopy while that of a cationic phosphorus dendrimer (third generation) and rose bengal were investigated by spectrofluorimetric methods. Spectroscopic analysis of these two systems revealed the formation of dendrimer-photosensitizer complexes via electrostatic interactions as well as π stacking. The stoichiometry of the rose bengal-cationic dendrimer complex was estimated to be 7:1 and 9:1 for the methylene blue-anionic dendrimer complex. The results suggest that these polyanionic or polycationic phosphorus dendrimers can be promising candidates as carriers in photodynamic therapy. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. SO2 EMISSION MEASUREMENT BY DOAS (DIFFERENTIAL OPTICAL ABSORPTION SPECTROSCOPY AND COSPEC (CORRELATION SPECTROSCOPY AT MERAPI VOLCANO (INDONESIA

    Directory of Open Access Journals (Sweden)

    Hanik Humaida

    2010-06-01

    Full Text Available The SO2 is one of the volcanic gases that can use as indicator of volcano activity. Commonly, SO2 emission is measured by COSPEC (Correlation Spectroscopy. This equipment has several disadvantages; such as heavy, big in size, difficulty in finding spare part, and expensive. DOAS (Differential Optical Absorption Spectroscopy is a new method for SO2 emission measurement that has advantages compares to the COSPEC. Recently, this method has been developed. The SO2 gas emission measurement of Gunung Merapi by DOAS has been carried out at Kaliadem, and also by COSPEC method as comparation. The differences of the measurement result of both methods are not significant. However, the differences of minimum and maximum result of DOAS method are smaller than that of the COSPEC. It has range between 51 ton/day and 87 ton/day for DOAS and 87 ton/day and 201 ton/day for COSPEC. The measurement of SO2 gas emission evaluated with the seismicity data especially the rockfall showed the presence of the positive correlation. It may cause the gas pressure in the subsurface influencing instability of 2006 eruption lava.   Keywords: SO2 gas, Merapi, DOAS, COSPEC

  16. Laser-Induced Breakdown Spectroscopy Infrared Emission From Inorganic and Organic Substances

    National Research Council Canada - National Science Library

    Yang, C.S; Brown, E; Hommerich, U; Trivedi, S. B; Snyder, A. P; Samuels, A. C

    2006-01-01

    Laser-induced breakdown spectroscopy (LIBS) has been established as a powerful method for identifying trace elemental contaminants by analyzing the atomic spectral emission lines that result subsequent to plasmas generated by laser power...

  17. Molecular speciation of phosphorus in organic amendments and amended soils using nuclear magnetic resonance and X-ray absorption spectroscopies

    International Nuclear Information System (INIS)

    Ajibove, B.

    2007-01-01

    Characterization of phosphorus (P) in organic amendments is essential for environmentally sustainable fertilization of agricultural soils. The sequential chemical extraction (SCE) technique commonly used for P characterization does not provide any direct molecular information about P species. Studies were conducted to characterize P species in organic amendments and amended soils at a molecular level. The SCE was used to fractionate P in organic amendments including biosolids, hog, dairy and beef cattle manures, and poultry litter. The extracts were analyzed for total P and P species using inductively coupled plasma - optical emission spectroscopy (ICP-OES) and solution 31 P nuclear magnetic resonance (NMR) spectroscopy, respectively. The relative proportions of P species in intact organic amendments and residues after each extraction, and calcareous soils amended with organic amendments and monoammonium phosphate (MAP) were estimated using the synchrotron-based P 1s X-ray absorption near edge structure (XANES) spectroscopy. The solution 31 P NMR provided a detailed characterization of organic P in the non-labile NaOH and HCl fractions of organic amendments, but was limited in characterizing the labile fractions of most of these organic amendments due to their proneness to alkaline hydrolysis. The XANES analysis, however, identified the actual chemical species constituting the labile P that was only characterized as inorganic P or orthophosphates by sequential extraction and solution 31 P NMR. In the amended Vertisolic and Chernozemic soils, XANES analysis estimated 'soluble and adsorbed P' as the dominant P species. For the Vertisolic soil, both the unamended and soil amended with biosolids and MAP contained hydroxyapatite (HAP). In addition, soil amended with biosolids, hog and dairy manures contained β-tricalcium phosphate (TRICAL), a more soluble CaP than HAP. TRICAL was found in all amended soils except in that amended with hog manure, while HAP was present

  18. Emission spectroscopy on a supersonically expanding argon/silane plasma

    NARCIS (Netherlands)

    Meeusen, G.J.; Ershov-Pavlov, E.A.; Meulenbroeks, R.F.G.; Sanden, van de M.C.M.; Schram, D.C.

    1992-01-01

    Results from emission spectroscopy measurements on an Ar/SiH/sub 4/ plasma jet which is used for fast deposition of amorphous hydrogenated silicon are presented. The jet is produced by allowing a thermal cascaded arc plasma in argon (I=60 A, V=80 V, Ar flow=60 scc/s and pressure 4*10/sup 4/ Pa) to

  19. The detection of phosphorus in the tissue of bomb victims in Gaza.

    Science.gov (United States)

    Thomsen, Jørgen L; Worm-Leonhard, Martin

    2010-01-01

    One of the authors went on a fact finding mission to Gaza immediately after the termination of the Israeli invasion. One of the allegations towards the invading Israeli army was the use of phosphorus bombs. The author was able to take samples of tissue from burn victims. Attempts were made to demonstrate the presence of phosphorus in the burn wounds. Using histology and Raman spectroscopy it was found with a high degree of probability that phosphorus was present, although it was not proven with absolute certainty.

  20. Deep level transient spectroscopic investigation of phosphorus-doped silicon by self-assembled molecular monolayers.

    Science.gov (United States)

    Gao, Xuejiao; Guan, Bin; Mesli, Abdelmadjid; Chen, Kaixiang; Dan, Yaping

    2018-01-09

    It is known that self-assembled molecular monolayer doping technique has the advantages of forming ultra-shallow junctions and introducing minimal defects in semiconductors. In this paper, we report however the formation of carbon-related defects in the molecular monolayer-doped silicon as detected by deep-level transient spectroscopy and low-temperature Hall measurements. The molecular monolayer doping process is performed by modifying silicon substrate with phosphorus-containing molecules and annealing at high temperature. The subsequent rapid thermal annealing drives phosphorus dopants along with carbon contaminants into the silicon substrate, resulting in a dramatic decrease of sheet resistance for the intrinsic silicon substrate. Low-temperature Hall measurements and secondary ion mass spectrometry indicate that phosphorus is the only electrically active dopant after the molecular monolayer doping. However, during this process, at least 20% of the phosphorus dopants are electrically deactivated. The deep-level transient spectroscopy shows that carbon-related defects are responsible for such deactivation.

  1. Long-wave, infrared laser-induced breakdown (LIBS) spectroscopy emissions from energetic materials.

    Science.gov (United States)

    Yang, Clayton S-C; Brown, Ei E; Hommerich, Uwe; Jin, Feng; Trivedi, Sudhir B; Samuels, Alan C; Snyder, A Peter

    2012-12-01

    Laser-induced breakdown spectroscopy (LIBS) has shown great promise for applications in chemical, biological, and explosives sensing and has significant potential for real-time standoff detection and analysis. In this study, LIBS emissions were obtained in the mid-infrared (MIR) and long-wave infrared (LWIR) spectral regions for potential applications in explosive material sensing. The IR spectroscopy region revealed vibrational and rotational signatures of functional groups in molecules and fragments thereof. The silicon-based detector for conventional ultraviolet-visible LIBS operations was replaced with a mercury-cadmium-telluride detector for MIR-LWIR spectral detection. The IR spectral signature region between 4 and 12 μm was mined for the appearance of MIR and LWIR-LIBS emissions directly indicative of oxygenated breakdown products as well as dissociated, and/or recombined sample molecular fragments. Distinct LWIR-LIBS emission signatures from dissociated-recombination sample molecular fragments between 4 and 12 μm are observed for the first time.

  2. Supplemental Report: Application of Emission Spectroscopy to Monitoring Technetium

    International Nuclear Information System (INIS)

    Spencer, W.A.

    2000-01-01

    This report provides supplemental information to an earlier report BNF-98-003-0199, ''Evaluation of Emission Spectroscopy for the On-Line Analysis of Technetium''. In this report data is included from real Hanford samples as well as for solutions spiked with technetium. This supplemental work confirms the ability of ICP-ES to monitor technetium as it breaks through an ion exchange process

  3. Measurement of Anomalously Strong Emission from the 1s-9p Transition in the Spectrum of H-like Phosphorus Following Charge Exchange with Molecular Hydrogen

    Science.gov (United States)

    Leutenegger, M. A.; Beiersdorfer, P.; Brown, G. V.; Kelley, R. L.; Porter, F. S.

    2010-01-01

    We have measured K-shell x-ray spectra of highly ionized argon and phosphorus following charge exchange with molecular hydrogen at low collision energy in an electron beam ion trap using an x-ray calorimeter array with approx.6 eV resolution. We find that the emission at the high-end of the Lyman series is greater by a factor of two for phosphorus than for argon, even though the measurement was performed concurrently and the atomic numbers are similar. This does not agree with current theoretical models and deviates from the trend observed in previous measurements.

  4. Lamb shift measurement in hydrogenlike phosphorus

    International Nuclear Information System (INIS)

    Mueller, D.; Gassen, J.; Kremer, L.

    1988-01-01

    In hydrogenlike phosphorus ions the 2S 1/2 -2P 1/2 energy splitting (Lamb shift) has been found to be E exp (LS)=0.08343(29) eV using laser spectroscopy. This result is to be compared with the most recent theoretical value E th (LS)=0.08376(4) eV by Mohr and Johnson and Soff

  5. Correlation between substrate bias, growth process and structural properties of phosphorus incorporated tetrahedral amorphous carbon films

    International Nuclear Information System (INIS)

    Liu Aiping; Zhu Jiaqi; Han Jiecai; Wu Huaping; Jia Zechun

    2007-01-01

    We investigate the growth process and structural properties of phosphorus incorporated tetrahedral amorphous carbon (ta-C:P) films which are deposited at different substrate biases by filtered cathodic vacuum arc technique with PH 3 as the dopant source. The films are characterized by X-ray photoelectron spectroscopy (XPS), atomic force microscopy, Raman spectroscopy, residual stress measurement, UV/VIS/NIR absorption spectroscopy and temperature-dependent conductivity measurement. The atomic fraction of phosphorus in the films as a function of substrate bias is obtained by XPS analysis. The optimum bias for phosphorus incorporation is about -80 V. Raman spectra show that the amorphous structures of all samples with atomic-scaled smooth surface are not remarkably changed when PH 3 is implanted, but some small graphitic crystallites are formed. Moreover, phosphorus impurities and higher-energetic impinging ions are favorable for the clustering of sp 2 sites dispersed in sp 3 skeleton and increase the level of structural ordering for ta-C:P films, which further releases the compressive stress and enhances the conductivity of the films. Our analysis establishes an interrelationship between microstructure, stress state, electrical properties, and substrate bias, which helps to understand the deposition mechanism of ta-C:P films

  6. Optical Emission Spectroscopy of Plasma in Hybrid Pulsed Laser Deposition System

    Czech Academy of Sciences Publication Activity Database

    Novotný, Michal; Jelínek, Miroslav; Bulíř, Jiří; Lančok, Ján; Jastrabík, Lubomír; Zelinger, Zdeněk

    2002-01-01

    Roč. 52, Suppl. D (2002), s. 292-298 ISSN 0011-4626 R&D Projects: GA AV ČR IAA1010110 Keywords : optical emission spectroscopy * pulsed laser deposition * RF discharge Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.311, year: 2002

  7. Study of atmospheric air AC glow discharge using optical emission spectroscopy and near infrared diode laser cavity ringdown spectroscopy

    Science.gov (United States)

    Srivastava, Nimisha; Wang, Chuji; Dibble, Theodore S.

    2008-11-01

    AC glow discharges were generated in atmospheric pressure by applying high voltage AC in the range of 3500-15000 V to a pair of stainless steel electrodes separated by an air gap. The discharges were characterized by optical emission spectroscopy (OES) and continuous wave cavity ringdown spectroscopy (cw-CRDS). The electronic (Tex), vibrational (Tv), and rotational (Tr) temperatures were measured. Spectral stimulations of the emission spectra of several vibronic bands of the 2^nd positive system of N2, the 1^st negative system of N2^+, the (0,1,2,3-0) bands of NO (A-X), and the (0-0) band of OH (A-X), which were obtained under various plasma operating conditions, show that Tr, Tv, and Tex are in the ranges of 2000 - 3800, 3500 - 5000, and 6000 - 10500^ K, respectively. Emission spectra show that OH concentration increases while NO concentration decreases with an increase of electrode spacing. The absorption spectra of H2O and OH overtone in the near infrared (NIR) were measured by the cw-CRDS with a telecommunications diode laser at wavelength near 1515 nm.

  8. Characterization of human breast disease using phosphorus magnetic resonance spectroscopy and proton magnetic resonance imaging

    International Nuclear Information System (INIS)

    Merchant, T.E.

    1992-01-01

    This thesis provides the fundamental characterization and differentiation of breast tissues using in vivo and ex vivo MR techniques in the hope that these techniques and experimental findings will be used on a larger scale and in a predictive manner in order to improve the specificity of diagnosis and treatment of breast cancer. In this dissertation, clinical studies were performed using proton magnetic resonance imaging and phosphorus magnetic resonance spectro-scopy ( 31 P MRS) to characterize and differentiate malignant breast tumors, benign breast tumors and normal breast tissues in vivo. These studies were carried out following the methodical characterization of chemical extracts of malignant breast tumor, benign breast tumor and normal breast parenchymal surgical tissue specimens using high resolution 31 P MRS. Alterations in breast tissue metabolism, as a result of pathological processes, were postulated to be responsible for measurable differences between malignant breast tumors, benign breast tumors and normal breast tissues using magnetic resonance techniques. (author). 365 refs.; 37 figs.; 25 tabs

  9. Terrestrial bryophytes as indicators of fluoride emission from a phosphorus plant, Long Harbour, Newfoundland, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, B.A.; Thompson, L.K.; Sidhu, S.S.

    1979-01-01

    A study of the effects of fluoride emissions (HF, SiF/sub 4/) on certain species of bryophytes was carried out in the vicinity of an industrial palnt producing elemental phosphorus at Long Harbour, Nfld. Damage symptoms varied from mild phyllid chlorosis (yellowing) to severe browning of up to 95% of the phyllids. Polytrichum commune Hedw. was the main bryophyte species used in the survey. Random collections from 45 sample sites were analysed for total fluoride. The fluoride concentrations in phyllid tissue ranged from a high of 6066 ppm (dry weight) at a distance of 1 km northeast of the emission source to 44 ppm (dry weight) 11.7 km northeast of the emission source in the direction of the prevailing wind. Control samples were obtained from similar sites in areas far removed from the industrial plant and contained, on average, 11.3 ppm (dry weight). The concentration of fluoride in the bryophyte phyllid tissue was inversely correlated with distance from the emission source, in the direction of the prevailing wind. The severity of acropetal scorching was found to be correlated with the concentration of fluoride in the bryophyte phyllid tissue, and in addition, samples high in fluoride had fewer sporophytes. Fluoride concentrations in bryophyte tissue are compared with concentrations of fluoride in the needles of balsam fir, Abies Balsamea I., in four damage zones, and also with available and total fluoride in soil humus and concentrations of fluoride in air. The total area affected by fluoride emissions was increased using bryophytes as the pollution indicator species, especially in areas far from the industrial plant.

  10. Auger electron spectroscopy, ionization loss spectroscopy, appearance potential spectroscopy

    International Nuclear Information System (INIS)

    Riwan, R.

    1973-01-01

    The spectroscopy of surfaces using an incident electron beam is studied. The fundamental mechanisms are discussed together with the parameters involved in Auger emission: excitation of the atom, de-excitation by electron emission, and the migration of electrons towards the surface and their ejection. Some examples of applications are given (surface structures, metallurgy, chemical information). Two new techniques for analyzing surfaces are studied: ionization spectroscopy, and appearance potential spectroscopy [fr

  11. [Research progress on phosphorus budgets and regulations in reservoirs].

    Science.gov (United States)

    Shen, Xiao; Li, Xu; Zhang, Wang-shou

    2014-12-01

    Phosphorus is an important limiting factor of water eutrophication. A clear understanding of its budget and regulated method is fundamental for reservoir ecological health. In order to pro- mote systematic research further and improve phosphorus regulation system, the budget balance of reservoir phosphorus and its influencing factors were concluded, as well as conventional regulation and control measures. In general, the main phosphorus sources of reservoirs include upstream input, overland runoff, industrial and domestic wastewater, aquaculture, atmospheric deposition and sediment release. Upstream input is the largest phosphorus source among them. The principal output path of phosphorus is the flood discharge, the emission load of which is mainly influenced by drainage patterns. In addition, biological harvest also can export a fraction of phosphorus. There are some factors affecting the reservoir phosphorus balance, including reservoirs' function, hydrological conditions, physical and chemical properties of water, etc. Therefore, the phosphorus budgets of different reservoirs vary greatly, according to different seasons and regions. In order to reduce the phosphorus loading in reservoirs, some methods are carried out, including constructed wetlands, prefix reservoir, sediment dredging, biomanipulation, etc. Different methods need to be chosen and combined according to different reservoirs' characteristics and water quality management goals. Thus, in the future research, it is reasonable to highlight reservoir ecological characteristics and proceed to a complete and systematic analysis of the inherent complexity of phosphorus budget and its impact factors for the reservoirs' management. Besides, the interaction between phosphorus budget and other nutrients in reservoirs also needs to be conducted. It is fundamental to reduce the reservoirs' phosphorus loading to establish a scientific and improved management system based on those researches.

  12. Characterisation of a micro-plasma device sensor using electrical measurements and emission spectroscopy

    International Nuclear Information System (INIS)

    Mariotti, D.

    2002-04-01

    This thesis reports on research undertaken on the characterisation of a micro-plasma device to be used for gas analysis by mean of plasma emission spectroscopy. The work covers aspects related to the micro-plasma electrical and optical emission parameters, and their importance for the utilisation of the micro-plasma device in gas analysis. Experimental results have been used to analyse the fundamental micro-plasma processes and to develop a model, which could provide additional information. This dissertation contains a general literature review of topics related to plasma physics, plasma emission spectroscopy, gas analysis (chemical analysis and artificial olfaction) and other micro-plasma applications. Experimental work focuses on two main areas: electrical measurements and emission measurements. Firstly, electrical measurements are taken and interpretations are given. Where necessary, new theoretical treatments are suggested in order to describe better the physical phenomena. Plasma emission has been considered under different working conditions. This allowed the characterisation of the micro-plasma emission and also a better understanding of the micro-plasma processes. On the basis of the experimental data obtained and other assumptions a model has been developed. A computer simulation based on this model provided additional useful information on the micro- plasma behaviour. The first fundamental implication of this new research is the peculiar behaviour of the micro-plasma. This micro-plasma exhibited deviations from Paschen law and strong dependency on cathode material, which contributed to the formation of a low current stable regime. These results have been followed by physical interpretations and theoretical descriptions. The second implication is the establishment of the boundaries and of the influencing parameters for plasma emission spectroscopy as an analytical tool in this particular micro-plasma. From the applied perspective this study has shown that

  13. A comparative study of the enhancement of molecular emission in a spatially confined plume through optical emission spectroscopy and probe beam deflection measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Dayu; Liang, Peipei; Wu, Jiada; Xu, Ning; Ying, Zhifeng; Sun, Jian, E-mail: jsun@fudan.edu.cn

    2013-01-01

    The spatial confinement effects of shock wave on the expansion of a carbon plume induced by pulsed laser ablation of graphite in air and the enhancement of the plume emission were studied by optical emission spectroscopy and probe beam deflection measurements. A metal disk was set in the way of the ablation-generated shock wave to block and reflect the supersonically propagating shock wave. The reflected shock wave propagated backwards and confined the expanding plume. The optical emission of CN molecules was enhanced in contrast to the case without the block disk and the emission enhancement was dependent on the position of the disk. Based on the results of time-integrated and -resolved optical emission spectroscopy, and the time- and space-resolved probe beam deflection measurements, the processes occurring in the plume were discussed and the mechanisms responsible for the enhancement of molecular emission in the spatially confined plume were investigated. - Highlights: ► Spatial confinement and optical emission enhancement of carbon plume were studied. ► Ablation-generated shockwave propagating in air was reflected by a block disk. ► The effects of reflected shockwave on the emission enhancement were confirmed. ► The reflect shockwave confined the carbon plume and enhanced the plume emission.

  14. A comparative study of the enhancement of molecular emission in a spatially confined plume through optical emission spectroscopy and probe beam deflection measurements

    International Nuclear Information System (INIS)

    Ding, Dayu; Liang, Peipei; Wu, Jiada; Xu, Ning; Ying, Zhifeng; Sun, Jian

    2013-01-01

    The spatial confinement effects of shock wave on the expansion of a carbon plume induced by pulsed laser ablation of graphite in air and the enhancement of the plume emission were studied by optical emission spectroscopy and probe beam deflection measurements. A metal disk was set in the way of the ablation-generated shock wave to block and reflect the supersonically propagating shock wave. The reflected shock wave propagated backwards and confined the expanding plume. The optical emission of CN molecules was enhanced in contrast to the case without the block disk and the emission enhancement was dependent on the position of the disk. Based on the results of time-integrated and -resolved optical emission spectroscopy, and the time- and space-resolved probe beam deflection measurements, the processes occurring in the plume were discussed and the mechanisms responsible for the enhancement of molecular emission in the spatially confined plume were investigated. - Highlights: ► Spatial confinement and optical emission enhancement of carbon plume were studied. ► Ablation-generated shockwave propagating in air was reflected by a block disk. ► The effects of reflected shockwave on the emission enhancement were confirmed. ► The reflect shockwave confined the carbon plume and enhanced the plume emission

  15. Atomic emission spectroscopy for the on-line monitoring of incineration processes

    NARCIS (Netherlands)

    Timmermans, E.A.H.; de Groote, F.P.J.; Jonkers, J.; Gamero, A.; Sola, A.; Mullen, van der J.J.A.M.

    2003-01-01

    A diagnostic measurement system based on atomic emission spectroscopy has been developed for the purpose of on-line monitoring of hazardous elements in industrial combustion gases. The aim was to construct a setup with a high durability for rough and variable experimental conditions, e.g. a strongly

  16. Extracting chemical information from high-resolution Kβ X-ray emission spectroscopy

    Science.gov (United States)

    Limandri, S.; Robledo, J.; Tirao, G.

    2018-06-01

    High-resolution X-ray emission spectroscopy allows studying the chemical environment of a wide variety of materials. Chemical information can be obtained by fitting the X-ray spectra and observing the behavior of some spectral features. Spectral changes can also be quantified by means of statistical parameters calculated by considering the spectrum as a probability distribution. Another possibility is to perform statistical multivariate analysis, such as principal component analysis. In this work the performance of these procedures for extracting chemical information in X-ray emission spectroscopy spectra for mixtures of Mn2+ and Mn4+ oxides are studied. A detail analysis of the parameters obtained, as well as the associated uncertainties is shown. The methodologies are also applied for Mn oxidation state characterization of double perovskite oxides Ba1+xLa1-xMnSbO6 (with 0 ≤ x ≤ 0.7). The results show that statistical parameters and multivariate analysis are the most suitable for the analysis of this kind of spectra.

  17. Evidence from in vivo 31-phosphorus magnetic resonance spectroscopy phosphodiesters that exhaled ethane is a biomarker of cerebral n-3 polyunsaturated fatty acid peroxidation in humans

    Directory of Open Access Journals (Sweden)

    Hamilton Gavin

    2008-04-01

    Full Text Available Abstract Background This study tested the hypothesis that exhaled ethane is a biomarker of cerebral n-3 polyunsaturated fatty acid peroxidation in humans. Ethane is released specifically following peroxidation of n-3 polyunsaturated fatty acids. We reasoned that the cerebral source of ethane would be the docosahexaenoic acid component of membrane phospholipids. Breakdown of the latter also releases phosphorylated polar head groups, giving rise to glycerophosphorylcholine and glycerophosphorylethanolamine, which can be measured from the 31-phosphorus neurospectroscopy phosphodiester peak. Schizophrenia patients were chosen because of evidence of increased free radical-mediated damage and cerebral lipid peroxidation in this disorder. Methods Samples of alveolar air were obtained from eight patients and ethane was analyzed and quantified by gas chromatography and mass spectrometry (m/z = 30. Cerebral 31-phosphorus spectra were obtained from the same patients at a magnetic field strength of 1.5 T using an image-selected in vivo spectroscopy sequence (TR = 10 s; 64 signal averages localized on a 70 × 70 × 70 mm3 voxel. The quantification of the 31-phosphorus signals using prior knowledge was carried out in the temporal domain after truncating the first 1.92 ms of the signal to remove the broad component present in the 31-phosphorus spectra. Results The ethane and phosphodiester levels, expressed as a percentage of the total 31-phosphorus signal, were positively and significantly correlated (rs = 0.714, p Conclusion Our results support the hypothesis that the measurement of exhaled ethane levels indexes cerebral n-3 lipid peroxidation. From a practical viewpoint, if human cerebral n-3 polyunsaturated fatty acid catabolism can be measured by ethane in expired breath, this would be more convenient than determining the area of the 31-phosphorus neurospectroscopy phosphodiester peak.

  18. Infrared-emission spectroscopy of CO on Ni

    International Nuclear Information System (INIS)

    Chiang, S.; Tobin, R.G.; Richards, P.L.

    1982-09-01

    We report the first observation of thermally emitted infrared radiation from vibrational modes of molecules adsorbed on clean, single-crystal metal surfaces. The observation of emission from CO adsorbed on Ni demonstrates the surface sensitivity of a novel apparatus for infrared vibrational spectroscopy, with a resolution of 1 to 15 cm -1 over the frequency range from 330 to 3000 cm -1 . A liquid-helium-cooled grating spectrometer measures the thermal radiation from a room-temperature, single-crystal sample, which is mounted in an ultrahigh-vacuum system. Measurements of frequencies and linewidths of CO on a single-crystal Ni sample, as a function of coverage, are discussed

  19. DETECTION OF REST-FRAME OPTICAL LINES FROM X-SHOOTER SPECTROSCOPY OF WEAK EMISSION-LINE QUASARS

    International Nuclear Information System (INIS)

    Plotkin, Richard M.; Gallo, Elena; Shemmer, Ohad; Trakhtenbrot, Benny; Anderson, Scott F.; Brandt, W. N.; Luo, Bin; Schneider, Donald P.; Fan, Xiaohui; Lira, Paulina; Richards, Gordon T.; Strauss, Michael A.; Wu, Jianfeng

    2015-01-01

    Over the past 15 yr, examples of exotic radio-quiet quasars with intrinsically weak or absent broad emission line regions (BELRs) have emerged from large-scale spectroscopic sky surveys. Here, we present spectroscopy of seven such weak emission line quasars (WLQs) at moderate redshifts (z = 1.4–1.7) using the X-shooter spectrograph, which provides simultaneous optical and near-infrared spectroscopy covering the rest-frame ultraviolet (UV) through optical. These new observations effectively double the number of WLQs with spectroscopy in the optical rest-frame, and they allow us to compare the strengths of (weak) high-ionization emission lines (e.g., C iv) to low-ionization lines (e.g., Mg ii, Hβ, Hα) in individual objects. We detect broad Hβ and Hα emission in all objects, and these lines are generally toward the weaker end of the distribution expected for typical quasars (e.g., Hβ has rest-frame equivalent widths ranging from 15–40 Å). However, these low-ionization lines are not exceptionally weak, as is the case for high-ionization lines in WLQs. The X-shooter spectra also display relatively strong optical Fe ii emission, Hβ FWHM ≲ 4000 km s −1 , and significant C iv blueshifts (≈1000–5500 km s −1 ) relative to the systemic redshift; two spectra also show elevated UV Fe ii emission, and an outflowing component to their (weak) Mg ii emission lines. These properties suggest that WLQs are exotic versions of “wind-dominated” quasars. Their BELRs either have unusual high-ionization components, or their BELRs are in an atypical photoionization state because of an unusually soft continuum

  20. New methods and applications in emission spectroscopy (1960)

    International Nuclear Information System (INIS)

    Baudin, G.

    1960-01-01

    Emission spectroscopy, are already well-established instrumental analytical technique, has in recent years known important developments. Two mains factors are responsible; firstly the demands of metallurgy for purer and purer materials or alloys which are increasingly complex and difficult to analyse by chemical means; secondly, progress in optics, especially in the production of gratings, and in electronics in the field of photomultiplier tubes. We will not here catalogue all the new applications and methods, but we will consider a few amongst the most representative outside the conventional field. (author) [fr

  1. High-resolution X-ray emission spectroscopy with transition-edge sensors: present performance and future potential

    Energy Technology Data Exchange (ETDEWEB)

    Uhlig, J.; Doriese, W. B.; Fowler, J. W.; Swetz, D. S.; Jaye, C.; Fischer, D. A.; Reintsema, C. D.; Bennett, D. A.; Vale, L. R.; Mandal, U.; O' Neil, G. C.; Miaja-Avila, L.; Joe, Y. I.; El Nahhas, A.; Fullagar, W.; Parnefjord Gustafsson, F.; Sundström, V.; Kurunthu, D.; Hilton, G. C.; Schmidt, D. R.; Ullom, J. N.

    2015-04-21

    X-ray emission spectroscopy (XES) is a powerful element-selective tool to analyze the oxidation states of atoms in complex compounds, determine their electronic configuration, and identify unknown compounds in challenging environments. Until now the low efficiency of wavelength-dispersive X-ray spectrometer technology has limited the use of XES, especially in combination with weaker laboratory X-ray sources. More efficient energy-dispersive detectors have either insufficient energy resolution because of the statistical limits described by Fano or too low counting rates to be of practical use. This paper updates an approach to high-resolution X-ray emission spectroscopy that uses a microcalorimeter detector array of superconducting transition-edge sensors (TESs). TES arrays are discussed and compared with conventional methods, and shown under which circumstances they are superior. It is also shown that a TES array can be integrated into a table-top time-resolved X-ray source and a soft X-ray synchrotron beamline to perform emission spectroscopy with good chemical sensitivity over a very wide range of energies.

  2. Fluorescence excitation-emission matrix spectroscopy for degradation monitoring of machinery lubricants

    Science.gov (United States)

    Sosnovski, Oleg; Suresh, Pooja; Dudelzak, Alexander E.; Green, Benjamin

    2018-02-01

    Lubrication oil is a vital component of heavy rotating machinery defining the machine's health, operational safety and effectiveness. Recently, the focus has been on developing sensors that provide real-time/online monitoring of oil condition/lubricity. Industrial practices and standards for assessing oil condition involve various analytical methods. Most these techniques are unsuitable for online applications. The paper presents the results of studying degradation of antioxidant additives in machinery lubricants using Fluorescence Excitation-Emission Matrix (EEM) Spectroscopy and Machine Learning techniques. EEM Spectroscopy is capable of rapid and even standoff sensing; it is potentially applicable to real-time online monitoring.

  3. Organic phosphorus fractionation in wetland soil profiles by chemical extraction and phosphorus-31 nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Li, Min; Zhang, Jing; Wang, Guangqian; Yang, Haijun; Whelan, Michael J.; White, Sue M.

    2013-01-01

    Highlights: ► Chemical sequential extraction and 31 P NMR spectroscopy were used for organic P analysis. ► Organic P includes orthophosphate, monoester and diester phosphate and pyrophosphate. ► Highly resistant organic P and monoester phosphate were the dominant organic P. ► HCl pretreatment can remove most inorganic P and increase organic P recovery rate. ► A comprehensive organic P chemical sequential fractionation approach was proposed. - Abstract: Organic P (OP) plays an important role in soil P cycling and is a potential P source for wetland plants. In this study, a modified chemical sequential fractionation method and 31 P nuclear magnetic resonance spectroscopy ( 31 P NMR) of NaOH–EDTA extracts were used to examine the distribution of organic P fractions and compounds in soil profiles of the Beijing Yeyahu Wetland, China. The influence of acid treatment prior to NaOH–EDTA extraction on 31 P NMR spectra was also investigated. Results show that highly resistant OP was the major class of organic P. The rank order of organic P fractions was highly resistant OP (on average accounting for 68.5% of total OP) > moderately resistant OP (15.8%m of total OP) > moderately labile OP (11.4% of total OP) > labile OP (4.3% of total OP). Most of the organic P fractions decreased with soil depth due to the accumulation of plant residues in surface soils and the deposition and diagenesis of soils. Moderately (r = 0.586, p < 0.01) and highly (r = 0.741, p < 0.01) resistant OP fractions were positively correlated with soil organic matter. Phosphorus compounds including orthophosphate (23–74.6% of total P in spectra), monoester phosphate (18.6–76%), diester phosphate (nil-7.8%) and pyrophosphate (nil-6.7%) were characterized using 31 P NMR. Monoester-P was the dominant soil organic P compound identified. The proportion of monoester-P increased significantly in NaOH–EDTA extracts with HCl pretreatment and it was confirmed by chemical analysis. Therefore, it

  4. Assessment of high precision, high accuracy Inductively Coupled Plasma-Optical Emission Spectroscopy to obtain concentration uncertainties less than 0.2% with variable matrix concentrations

    International Nuclear Information System (INIS)

    Rabb, Savelas A.; Olesik, John W.

    2008-01-01

    The ability to obtain high precision, high accuracy measurements in samples with complex matrices using High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy (HP-ICP-OES) was investigated. The Common Analyte Internal Standard (CAIS) procedure was incorporated into the High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy method to correct for matrix-induced changes in emission intensity ratios. Matrix matching and standard addition approaches to minimize matrix-induced errors when using High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy were also assessed. The High Performance Inductively Coupled Plasma-Optical Emission Spectroscopy method was tested with synthetic solutions in a variety of matrices, alloy standard reference materials and geological reference materials

  5. Electrically-inactive phosphorus re-distribution during low temperature annealing

    Science.gov (United States)

    Peral, Ana; Youssef, Amanda; Dastgheib-Shirazi, Amir; Akey, Austin; Peters, Ian Marius; Hahn, Giso; Buonassisi, Tonio; del Cañizo, Carlos

    2018-04-01

    An increased total dose of phosphorus (P dose) in the first 40 nm of a phosphorus diffused emitter has been measured after Low Temperature Annealing (LTA) at 700 °C using the Glow Discharge Optical Emission Spectrometry technique. This evidence has been observed in three versions of the same emitter containing different amounts of initial phosphorus. A stepwise chemical etching of a diffused phosphorus emitter has been carried out to prepare the three types of samples. The total P dose in the first 40 nm increases during annealing by 1.4 × 1015 cm-2 for the sample with the highly doped emitter, by 0.8 × 1015 cm-2 in the middle-doped emitter, and by 0.5 × 1015 cm-2 in the lowest-doped emitter. The presence of surface dislocations in the first few nanometers of the phosphorus emitter might play a role as preferential sites of local phosphorus gettering in phosphorus re-distribution, because the phosphorus gettering to the first 40 nm is lower when this region is etched stepwise. This total increase in phosphorus takes place even though the calculated electrically active phosphorus concentration shows a reduction, and the measured sheet resistance shows an increase after annealing at a low temperature. The reduced electrically active P dose is around 0.6 × 1015 cm-2 for all the emitters. This can be explained with phosphorus-atoms diffusing towards the surface during annealing, occupying electrically inactive configurations. An atomic-scale visual local analysis is carried out with needle-shaped samples of tens of nm in diameter containing a region of the highly doped emitter before and after LTA using Atom Probe Tomography, showing phosphorus precipitates of 10 nm and less before annealing and an increased density of larger precipitates after annealing (25 nm and less).

  6. Muscular sufficiency, serum protein, enzymes and bioenergetic studies in chronic malnutrition. [31-phosphorus magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, R K; Mittal, R D; Agarwal, K N; Agarwal, D K [Banaras Hindu Univ., Varanasi (India)

    1994-03-01

    Muscle sufficiency was significantly lower in 1336 children with chronic malnutrition of moderate to severe degree. 18 children with a chronic moderate degree of malnutrition and 8 well-nourished age-matched controls were selected for biochemical and 31-phosphorus magnetic resonance spectroscopy (31-P MRS) studies. The results shows that: (a) serum total protein, albumin, iron, calcium and inorganic phosphate were similar in both groups; (b) serum enzyme levels were significantly increased in the malnuourished group; (c) 31-P MRS showed significantly higher means for total ATP, [beta]-ATP, [alpha]-ATP and inorganic phosphate for the malnourished compared to the control group. In chronic malnutrition, proteins are maintained by degradation in muscle resulting in release of amino acids and enzymes. 31-P MRS studies showing increases in total ATP, [beta]-ATP and inorganic phosphate and a decrease in phosphocreatine suggest that ATP is maintained at the cost of phosphocreatine. 22 refs., 4 tabs. 1 fig.

  7. Emission Spectroscopy as a Probe into Photoinduced Intramolecular Electron Transfer in Polyazine Bridged Ru(II,Rh(III Supramolecular Complexes

    Directory of Open Access Journals (Sweden)

    Karen J. Brewer

    2010-08-01

    Full Text Available Steady-state and time-resolved emission spectroscopy are valuable tools to probe photochemical processes of metal-ligand, coordination complexes. Ru(II polyazine light absorbers are efficient light harvesters absorbing in the UV and visible with emissive 3MLCT excited states known to undergo excited state energy and electron transfer. Changes in emission intensity, energy or band-shape, as well as excited state lifetime, provide insight into excited state dynamics. Photophysical processes such as intramolecular electron transfer between electron donor and electron acceptor sub-units may be investigated using these methods. This review investigates the use of steady-state and time-resolved emission spectroscopy to measure excited state intramolecular electron transfer in polyazine bridged Ru(II,Rh(III supramolecular complexes. Intramolecular electron transfer in these systems provides for conversion of the emissive 3MLCT (metal-to-ligand charge transfer excited state to a non-emissive, but potentially photoreactive, 3MMCT (metal-to-metal charge transfer excited state. The details of the photophysics of Ru(II,Rh(III and Ru(II,Rh(III,Ru(II systems as probed by steady-state and time-resolved emission spectroscopy will be highlighted.

  8. Emission Spectroscopy of OH Radical in Water-Argon Arc Plasma Jet

    Czech Academy of Sciences Publication Activity Database

    Mašláni, Alan; Sember, Viktor

    2014-01-01

    Roč. 2014, April (2014), "952138"-"952138" ISSN 2314-4920 R&D Projects: GA ČR GAP205/11/2070 Institutional support: RVO:61389021 Keywords : Emission spectroscopy * OH radical * arc plasma jet Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.538, year: 2014 http://www.hindawi.com/journals/jspec/2014/952138/abs/

  9. Grain boundary phosphorus segregation under thermal aging in low alloy steels

    International Nuclear Information System (INIS)

    Nakata, Hayato; Fujii, Katsuhiko; Fukuya, Koji; Shibata, Masaaki; Kasada, Ryuta; Kimura, Akihiko

    2002-01-01

    Intergranular embrittlement due to grain boundary segregation of phosphorus is recognized as one of the potential degradation factors in irradiated reactor pressure vessel steels at high neutron fluences. In this study, investigations on low alloy steels thermally aged at 400-500degC were conducted to evaluate the correlation between phosphorus segregation and intergranular embrittlement. Phosphorus segregation determined using Auger electron spectroscopy increased after aging above 450degC and was in good agreement with the calculated value based on McLean model. No influence of thermal aging was observed in tensile properties. The ductile brittle transition temperature determined using 1/3 size charpy impact tests increased of 12degC after aging at 450degC for 3000 hours. These results indicated that there is a threshold level of phosphorus segregation for non-hardening embrittlement and that the level is around 0.14 for P/Fe peak ratio. (author)

  10. Grain boundary phosphorus segregation under thermal aging in low alloy steels

    Energy Technology Data Exchange (ETDEWEB)

    Nakata, Hayato; Fujii, Katsuhiko; Fukuya, Koji [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan); Shibata, Masaaki; Kasada, Ryuta; Kimura, Akihiko [Kyoto Univ. (Japan)

    2002-09-01

    Intergranular embrittlement due to grain boundary segregation of phosphorus is recognized as one of the potential degradation factors in irradiated reactor pressure vessel steels at high neutron fluences. In this study, investigations on low alloy steels thermally aged at 400-500degC were conducted to evaluate the correlation between phosphorus segregation and intergranular embrittlement. Phosphorus segregation determined using Auger electron spectroscopy increased after aging above 450degC and was in good agreement with the calculated value based on McLean model. No influence of thermal aging was observed in tensile properties. The ductile brittle transition temperature determined using 1/3 size charpy impact tests increased of 12degC after aging at 450degC for 3000 hours. These results indicated that there is a threshold level of phosphorus segregation for non-hardening embrittlement and that the level is around 0.14 for P/Fe peak ratio. (author)

  11. Utilization of synchrotron radiation in analytical chemistry. Soft X-ray emission and absorption spectroscopy

    International Nuclear Information System (INIS)

    Muramatsu, Yasuji

    2015-01-01

    Synchrotron soft X-ray spectroscopy includes three major types of spectroscopy such as X-ray absorption spectroscopy (XAS), X-ray emission spectroscopy (XES), and X-ray photoelectron spectroscopy (XPS). This paper takes up XAS and XES of soft X-rays, and briefly describes the principle. XAS is roughly classified into XANES (X-ray absorption near-edge structure) and EXAFS (extended X-ray absorption fine structure), and XANES is mainly used in the analysis based on XAS of soft X-rays. As the examples of the latest soft X-ray analyses, the following are introduced: (1) bandgap of boron implantation diamond and the local structure of boron, (2) catalytic sites in solid fuel cell carbon electrode, and (3) soft X-ray analysis under atmospheric pressure. (A.O.)

  12. Anisotropic in-plane thermal conductivity observed in few-layer black phosphorus

    Science.gov (United States)

    Luo, Zhe; Maassen, Jesse; Deng, Yexin; Du, Yuchen; Garrelts, Richard P.; Lundstrom, Mark S; Ye, Peide D.; Xu, Xianfan

    2015-01-01

    Black phosphorus has been revisited recently as a new two-dimensional material showing potential applications in electronics and optoelectronics. Here we report the anisotropic in-plane thermal conductivity of suspended few-layer black phosphorus measured by micro-Raman spectroscopy. The armchair and zigzag thermal conductivities are ∼20 and ∼40 W m−1 K−1 for black phosphorus films thicker than 15 nm, respectively, and decrease to ∼10 and ∼20 W m−1 K−1 as the film thickness is reduced, exhibiting significant anisotropy. The thermal conductivity anisotropic ratio is found to be ∼2 for thick black phosphorus films and drops to ∼1.5 for the thinnest 9.5-nm-thick film. Theoretical modelling reveals that the observed anisotropy is primarily related to the anisotropic phonon dispersion, whereas the intrinsic phonon scattering rates are found to be similar along the armchair and zigzag directions. Surface scattering in the black phosphorus films is shown to strongly suppress the contribution of long mean-free-path acoustic phonons. PMID:26472191

  13. Atomic and electronic structure of exfoliated black phosphorus

    International Nuclear Information System (INIS)

    Wu, Ryan J.; Topsakal, Mehmet; Jeong, Jong Seok; Wentzcovitch, Renata M.; Mkhoyan, K. Andre; Low, Tony; Robbins, Matthew C.; Haratipour, Nazila; Koester, Steven J.

    2015-01-01

    Black phosphorus, a layered two-dimensional crystal with tunable electronic properties and high hole mobility, is quickly emerging as a promising candidate for future electronic and photonic devices. Although theoretical studies using ab initio calculations have tried to predict its atomic and electronic structure, uncertainty in its fundamental properties due to a lack of clear experimental evidence continues to stymie our full understanding and application of this novel material. In this work, aberration-corrected scanning transmission electron microscopy and ab initio calculations are used to study the crystal structure of few-layer black phosphorus. Directly interpretable annular dark-field images provide a three-dimensional atomic-resolution view of this layered material in which its stacking order and all three lattice parameters can be unambiguously identified. In addition, electron energy-loss spectroscopy (EELS) is used to measure the conduction band density of states of black phosphorus, which agrees well with the results of density functional theory calculations performed for the experimentally determined crystal. Furthermore, experimental EELS measurements of interband transitions and surface plasmon excitations are also consistent with simulated results. Finally, the effects of oxidation on both the atomic and electronic structure of black phosphorus are analyzed to explain observed device degradation. The transformation of black phosphorus into amorphous PO 3 or H 3 PO 3 during oxidation may ultimately be responsible for the degradation of devices exposed to atmosphere over time

  14. Cerebral Magnesium Levels in Preeclampsia; A Phosphorus Magnetic Resonance Spectroscopy Study.

    Science.gov (United States)

    Nelander, Maria; Weis, Jan; Bergman, Lina; Larsson, Anders; Wikström, Anna-Karin; Wikström, Johan

    2017-07-01

    Magnesium sulfate (MgSO4) is used as a prophylaxis for eclamptic seizures. The exact mechanism of action is not fully established. We used phosphorus magnetic resonance spectroscopy (31P-MRS) to investigate if cerebral magnesium (Mg2+) levels differ between women with preeclampsia, normal pregnant, and nonpregnant women. This cross-sectional study comprised 28 women with preeclampsia, 30 women with normal pregnancies in corresponding gestational week (range: 23-41 weeks) and 11 nonpregnant healthy controls. All women underwent 31P-MRS from the parieto-occipital region of the brain and were interviewed about cerebral symptoms. Differences between groups were assessed by analysis of variance and Tukey's post-hoc test. Correlations between Mg2+ levels and specific neurological symptoms were estimated with Spearman's rank test. Mean maternal cerebral Mg2+ levels were lower in women with preeclampsia (0.12 mM ± 0.02) compared to normal pregnant controls (0.14 mM ± 0.03) (P = 0.04). Nonpregnant and normal pregnant women did not differ in Mg2+ levels. Among women with preeclampsia, lower Mg2+ levels correlated with presence of visual disturbances (P = 0.04). Plasma levels of Mg2+ did not differ between preeclampsia and normal pregnancy. Women with preeclampsia have reduced cerebral Mg2+ levels, which could explain the potent antiseizure prophylactic properties of MgSO4. Within the preeclampsia group, women with visual disturbances have lower levels of Mg2+ than those without such symptoms. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  15. Viologen-Phosphorus Dendrimers Inhibit α-Synuclein Fibrillation.

    Science.gov (United States)

    Milowska, Katarzyna; Grochowina, Justyna; Katir, Nadia; El Kadib, Abdelkrim; Majoral, Jean-Pierre; Bryszewska, Maria; Gabryelak, Teresa

    2013-03-04

    Inhibition of α-synuclein (ASN) fibril formation is a potential therapeutic strategy in Parkinson's disease and other synucleinopathies. The aim of this study was to examine the role of viologen-phosphorus dendrimers in the α-synuclein fibrillation process and to assess the structural changes in α-synuclein under the influence of dendrimers. ASN interactions with phosphonate and pegylated surface-reactive viologen-phosphorus dendrimers were examined by measuring the zeta potential, which allowed determining the number of dendrimer molecules that bind to the ASN molecule. The fibrillation kinetics and the structural changes were examined using ThT fluorescence and CD spectroscopy. Depending on the concentration of the used dendrimer and the nature of the reactive groups located on the surface, ASN fibrillation kinetics can be significantly reduced, and even, in the specific case of phosphonate dendrimers, the fibrillation can be totally inhibited at low concentrations. The presented results indicate that viologen-phosphorus dendrimers are able to inhibit ASN fibril formation and may be used as fibrillar regulating agents in neurodegenerative disorders.

  16. Lichens as indicators of fluoride emission from a phosphorus plant, Long Harbour, Newfoundland, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, B.A.; Thompson, L.K.

    1980-01-01

    Fluoride concentrations in the terrestrial lichens Cladina rangiferina (L.) Harm. and Cladina stellaris (Opiz.) Brodo. were correlated inversely with distance from an industrial plant producing elemental phosphorus at Long Harbour, Nfld., in the direction (NE) of the prevailing wind. The fluoride concentrations ranged from 2830 ppm dry weight in a severely damaged area close to the emission source to 15.5 ppm (dry weight) 12 km NE of the industrial plant. Control samples from unpolluted areas had an average fluoride content of 6.4 ppm dry weight. The minimum observed damage symptoms occurred when these lichens had a fluoride content of 25 ppm dry weight. Damage symptoms included discolouration and structure loss. Discolouration effects were not as pronounced as observed on Abies balsamea (L.) Mill. or on Polytrichum commune (Hedw.) but combined with structure loss allowed the degree of damage to be readily identified in the field. Fluoride concentrations in these terrestrial lichens are compared with levels in soil humus, A. balsamea and some terrestrial bryophytes in four damage zones. The lichen tissue had, on average, twice as much fluoride as occurred in soil humus from the same site and about one half the amount of fluoride found in the terrestrial bryophyte P. commune. The effects of fluoride emissions on the epiphytic lichens Hypogymnia physodes (L.) W. Wats. and Alectoria sarmentosa (Ach.) Ach. in this area are also discussed.

  17. Imbalanced phosphorus and nitrogen deposition in China's forests

    NARCIS (Netherlands)

    Du, Enzai; Vries, de Wim; Han, Wenxuan; Liu, Xuejun; Yan, Zhengbing; Jiang, Yuan

    2016-01-01

    Acceleration of anthropogenic emissions in China has substantially increased nitrogen (N) deposition during the last 3 decades and may result in an imbalance of atmospheric N and phosphorus (P) inputs in terrestrial ecosystems. However, the status of P deposition in China is poorly understood.

  18. Imaging of buried phosphorus nanostructures in silicon using scanning tunneling microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Oberbeck, Lars [Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); TOTAL Marketing Services, New Energies, La Défense 10, 92069 Paris La Défense Cedex (France); Reusch, Thilo C. G.; Hallam, Toby; Simmons, Michelle Y., E-mail: n.curson@ucl.ac.uk, E-mail: michelle.simmons@unsw.edu.au [Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); Schofield, Steven R. [Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); London Centre for Nanotechnology, UCL, London WC1H 0AH (United Kingdom); Department of Physics and Astronomy, UCL, London WC1E 6BT (United Kingdom); Curson, Neil J., E-mail: n.curson@ucl.ac.uk, E-mail: michelle.simmons@unsw.edu.au [Centre for Quantum Computation and Communication Technology, School of Physics, University of New South Wales, Sydney, New South Wales 2052 (Australia); London Centre for Nanotechnology, UCL, London WC1H 0AH (United Kingdom); Department of Electronic and Electrical Engineering, UCL, London WC1E 7JE (United Kingdom)

    2014-06-23

    We demonstrate the locating and imaging of single phosphorus atoms and phosphorus dopant nanostructures, buried beneath the Si(001) surface using scanning tunneling microscopy. The buried dopant nanostructures have been fabricated in a bottom-up approach using scanning tunneling microscope lithography on Si(001). We find that current imaging tunneling spectroscopy is suited to locate and image buried nanostructures at room temperature and with residual surface roughness present. From these studies, we can place an upper limit on the lateral diffusion during encapsulation with low-temperature Si molecular beam epitaxy.

  19. Imaging of buried phosphorus nanostructures in silicon using scanning tunneling microscopy

    International Nuclear Information System (INIS)

    Oberbeck, Lars; Reusch, Thilo C. G.; Hallam, Toby; Simmons, Michelle Y.; Schofield, Steven R.; Curson, Neil J.

    2014-01-01

    We demonstrate the locating and imaging of single phosphorus atoms and phosphorus dopant nanostructures, buried beneath the Si(001) surface using scanning tunneling microscopy. The buried dopant nanostructures have been fabricated in a bottom-up approach using scanning tunneling microscope lithography on Si(001). We find that current imaging tunneling spectroscopy is suited to locate and image buried nanostructures at room temperature and with residual surface roughness present. From these studies, we can place an upper limit on the lateral diffusion during encapsulation with low-temperature Si molecular beam epitaxy.

  20. Solid-state nuclear magnetic resonance studies of phosphorus and boron in coals and combustion residues

    Energy Technology Data Exchange (ETDEWEB)

    Burchill, P.; Howarth, O.W.; Richards, D.G.; Sword, B.J. (British Coal Corporation, Stoke Orchard (UK). Coal Research Establishment)

    1990-04-01

    Solid-state nuclear magnetic resonance spectroscopy with magic angle spinning (MAS-n.m.r.) was used to study the occurrence of phosphorus and boron in coal, and their fate on combustion. These elements are only minor components of coal, but may significantly influence the utilization properties. {sup 31} P MAS-n.m.r. spectroscopy has confirmed that phosphorus is present in coal predominantly as apatite. This mineral is thermally stable under oxidizing conditions, and survives largely unaltered in high temperature ashes. However, under the semi-reducing bed conditions of certain stoker-fired boilers, it may be decomposed, volatilizing the phosphorus. The {sup 31}P MAS-n.m.r. spectra of bonded deposits show phosphorus in a markedly different coordination environment to that in apatite, the chemical shift suggesting aluminium phosphate or boron phosphate. {sup 11}B MAS-n.m.r. spectra of coals exhibit resonances due to both trigonal and tetrahedrally coordinated boron. Trigonal boron is probably present as tourmaline, but the nature of the tetrahedral boron is less certain; it may be held in tetrahedral sites within certain clay minerals. In common with phosphorus, boron may be volatilized during combustion. The {sup 11}B MAS-n.m.r. spectra of bonded deposits show a tetrahedral resonance with a chemical shift quite consistent with that of boron phosphate. 39 refs., 9 figs., 5 tabs.

  1. Assisted Interpretation of Laser-Induced Fluorescence Spectra of Egg-Based Binding Media Using Total Emission Fluorescence Spectroscopy

    International Nuclear Information System (INIS)

    Anglos, D.; Nevin, A.

    2006-01-01

    Laser-induced fluorescence (LIF) spectroscopy can provide nondestructive, qualitative analysis of protein-based binding media found in artworks. Fluorescence emissions from proteins in egg yolk and egg white are due to auto fluorescent aromatic amino acids as well as other native and age-related fluorophores, but the potential of fluorescence spectroscopy for the differentiation between binding media is dependent on the choice of a suitable excitation wavelength and limited by problems in interpretation. However, a better understanding of emission spectra associated with LIF can be achieved following comparisons with total emission fluorescence spectra where a series of consecutive emission spectra are recorded over a specific range. Results using nanosecond UV laser sources for LIF of egg-based binding media are presented which are rationalised following comparisons with total emission spectra. Specifically, fluorescence is assigned to tryptophan and oxidation products of amino acids; in the case of egg yolk, fatty-acid polymerisation and age-related degradation products account for the formation of fluorophores.

  2. Phosphorus flows and balances of the European Union Member States

    Energy Technology Data Exchange (ETDEWEB)

    Dijk, Kimo C. van, E-mail: kimo.vandijk@wur.nl [Department of Soil Quality, Wageningen University and Research Centre, P.O. Box 47, 6700 AA, Wageningen (Netherlands); Lesschen, Jan Peter, E-mail: janpeter.lesschen@wur.nl [Department of Soil Quality, Wageningen University and Research Centre, P.O. Box 47, 6700 AA, Wageningen (Netherlands); Oenema, Oene, E-mail: oene.oenema@wur.nl [Department of Soil Quality, Wageningen University and Research Centre, P.O. Box 47, 6700 AA, Wageningen (Netherlands); Alterra, Wageningen University and Research Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands)

    2016-01-15

    Global society faces serious “phosphorus challenges” given the scarcity, essentiality, unequal global distribution and, at the same time, regional excess of phosphorus (P). Phosphorus flow studies can be used to analyze these challenges, providing insight into how society (re)uses and loses phosphorus, identifying potential solutions. Phosphorus flows were analyzed in detail for EU-27 and its Member States. To quantify food system and non-food flows, country specific data and historical context were considered. The sectors covered were crop production (CP), animal production (AP), food processing (FP), non-food production (NF) and consumption (HC). The results show that the EU-27 imported 2392 Gg P in 2005, half of which accumulated in agricultural soils (924 Gg) and half was lost as waste (1217 Gg). Net accumulation was 4.9 kg P/ha/year ranging between + 23.2 (Belgium) and − 2.8 (Slovakia). From the system losses, 54% was lost from HC in diverse waste flows and 28% from FP, mainly through incinerated slaughter residues. The largest HC losses (655 Gg) were wastewater (55%), food waste (27%), and pet excreta (11%). Phosphorus recycling rates were 73% in AP, 29% in FP, 21% in HC and ~ 0% in NF. The phosphorus use efficiencies showed that, relative to sector input, about 70% was taken up by crops (CP), 24% was retained in animals (AP), 52% was contained in food products (FP), 76% was stored in non-food materials (NF), and 21% was recycled (HC). Although wide-ranging variation between countries, generally phosphorus use in EU-27 was characterized by relatively (1) large dependency on (primary) imports, (2) long-term accumulation in agricultural soils, especially in west European countries, (3) leaky losses throughout entire society, especially emissions to the environment and sequestered waste, (4) little recycling with the exception of manure, and (5) low use efficiencies, because of aforementioned issues, providing ample opportunities for improvement

  3. Phosphorus flows and balances of the European Union Member States

    International Nuclear Information System (INIS)

    Dijk, Kimo C. van; Lesschen, Jan Peter; Oenema, Oene

    2016-01-01

    Global society faces serious “phosphorus challenges” given the scarcity, essentiality, unequal global distribution and, at the same time, regional excess of phosphorus (P). Phosphorus flow studies can be used to analyze these challenges, providing insight into how society (re)uses and loses phosphorus, identifying potential solutions. Phosphorus flows were analyzed in detail for EU-27 and its Member States. To quantify food system and non-food flows, country specific data and historical context were considered. The sectors covered were crop production (CP), animal production (AP), food processing (FP), non-food production (NF) and consumption (HC). The results show that the EU-27 imported 2392 Gg P in 2005, half of which accumulated in agricultural soils (924 Gg) and half was lost as waste (1217 Gg). Net accumulation was 4.9 kg P/ha/year ranging between + 23.2 (Belgium) and − 2.8 (Slovakia). From the system losses, 54% was lost from HC in diverse waste flows and 28% from FP, mainly through incinerated slaughter residues. The largest HC losses (655 Gg) were wastewater (55%), food waste (27%), and pet excreta (11%). Phosphorus recycling rates were 73% in AP, 29% in FP, 21% in HC and ~ 0% in NF. The phosphorus use efficiencies showed that, relative to sector input, about 70% was taken up by crops (CP), 24% was retained in animals (AP), 52% was contained in food products (FP), 76% was stored in non-food materials (NF), and 21% was recycled (HC). Although wide-ranging variation between countries, generally phosphorus use in EU-27 was characterized by relatively (1) large dependency on (primary) imports, (2) long-term accumulation in agricultural soils, especially in west European countries, (3) leaky losses throughout entire society, especially emissions to the environment and sequestered waste, (4) little recycling with the exception of manure, and (5) low use efficiencies, because of aforementioned issues, providing ample opportunities for improvement

  4. Exploring the Modes of Action of Phosphorus-Based Flame Retardants in Polymeric Systems

    Directory of Open Access Journals (Sweden)

    Sebastian Rabe

    2017-04-01

    Full Text Available Phosphorus-based flame retardants were incorporated into different, easily preparable matrices, such as polymeric thermoset resins and paraffin as a proposed model for polyolefins and investigated for their flame retardancy performance. The favored mode of action of each flame retardant was identified in each respective system and at each respective concentration. Thermogravimetric analysis was used in combination with infrared spectroscopy of the evolved gas to determine the pyrolysis behavior, residue formation and the release of phosphorus species. Forced flaming tests in the cone calorimeter provided insight into burning behavior and macroscopic residue effects. The results were put into relation to the phosphorus content to reveal correlations between phosphorus concentration in the gas phase and flame inhibition performance, as well as phosphorus concentration in the residue and condensed phase activity. Total heat evolved (fire load and peak heat release rate were calculated based on changes in the effective heat of combustion and residue, and then compared with the measured values to address the modes of action of the flame retardants quantitatively. The quantification of flame inhibition, charring, and the protective layer effect measure the non-linear flame retardancy effects as functions of the phosphorus concentration. Overall, this screening approach using easily preparable polymer systems provides great insight into the effect of phosphorus in different flame retarded polymers, with regard to polymer structure, phosphorus concentration, and phosphorus species.

  5. Study of the muscular metabolism using Phosphorus 31 Magnetic Resonance Spectroscopy (31P-MRS) in normal subjects

    International Nuclear Information System (INIS)

    Batista, T.S.; Salmon, C.E.G.; Santos, A.C.

    2008-01-01

    Phosphorus 31 Magnetic Resonance Spectroscopy ( 31 P-MRS) is a powerful technique for evaluating human muscular metabolism. Some reports indicated the behavior of phosphorylated metabolites (PCr, ADP and Pi) and other indirect parameters (intracellular pH and [Mg 2+ ]) in muscles at rest and after an exercise load. The aim of this work is a quantitative study of the phosphorylated metabolite levels in the calf muscle of normal subjects at rest and post-exercise, in order to create a normal control database. 31 P spectra of seven volunteers were acquired in both conditions. Firstly, different quantification methodologies were evaluated to use the more reliable. The P Cr metabolite was the more stable at rest and it had mono-exponential behavior after exercise. The Pi was the more sensible indicator of the physical activities. The time constants of the recuperation process are report for all the evaluated metabolites and parameters. Finally, the temporal behavior of phospho monoesters was quantified. (author)

  6. Evaluation of intergranular corrosion techniques to determine phosphorus segregation in NiCrMoV rotor steel

    International Nuclear Information System (INIS)

    Bruemmer, S.M.; Thomas, M.T.; Arey, B.W.

    1985-01-01

    Several chemical and electrochemical etching techniques have been evaluated for the indirect measurement of grain boundary phosphorus segregation. A picric acid based solution was found to promote intergranular attack proportional to the grain boundary phosphorus composition measured by Auger Electron Spectroscopy. Preliminary results indicate this solution may enable the nondestructive evaluation of a rotor steel's susceptibility to temper embrittlement and IGSCC

  7. Laboratory Studies Of Astrophysically-interesting Phosphorus-bearing Molecules

    Science.gov (United States)

    Ziurys, Lucy M.; Halfen, D. T.; Sun, M.; Clouthier, D. J.

    2009-05-01

    Over the past year, there has been a renewed interest in the presence of phosphorus-containing molecules in the interstellar medium. Recent observations have increased the number of known interstellar phosphorus-bearing species from two (PN, CP) to six with the identification of HCP, CCP, and PH3 in the carbon-rich circumstellar shell of IRC+10216 and PO in the oxygen-rich envelope of VY Canis Majoris. More species of this type may be present in the ISM, but laboratory rest frequencies, necessary for such detections, are not generally known for many potential molecules. To fill in this gap, we have been conducting measurements of the pure rotational spectra of phosphorus-containing molecules of astrophysical interest, using both millimeter/submm direct absorption and Fourier transform microwave (FTMW) spectroscopy. We have developed a new phosphorus source for this purpose. These methods cover the frequency ranges 65-850 GHz and 4-40 GHz, respectively. Our recent study of the CCP radical (X2Πr) using both of these techniques has resulted in its identification in IRC+10216. Rotational spectra of other molecules such as PCN, HPS, and CH3PH2 have been recorded. We will report on these species and additional new laboratory developments

  8. Phosphorus nuclear magnetic resonance in isolated perfused rat pancreas

    International Nuclear Information System (INIS)

    Matsumoto, Takehisa; Kanno, Tomio; Seo, Yoshiteru; Murakami, Masataka; Watari, Hiroshi

    1988-01-01

    Phosphorus nuclear magnetic resonance spectroscopy was applied to measure phosphorus energy metabolites in isolated perfused rat pancreas. The gland was perfused with a modified Krebs-Henseleit solution at room temperature (25 degree C). 31 P resonances of creatine phosphate (PCr), ATP, ADP, inorganic phosphate (P i ) and phosphomonoesters (PMEs) were observed in all the preparations of pancreas. In different individual preparations, the resonance of PCr varied, but those of ATP were almost the same. The initial levels of PCr and ATP in individual preparations, however, remained almost unchanged during perfusion with the standard solution for 2 h. When the perfusion was stopped, the levels of ATP and PCr decreased, while the levels of PME and P i increased. At that time, the P i resonance shfted to a higher magnetic field, indicating that the tissue pH decreased. On reperfusion, the tissue levels of phosphorus compounds and the tissue pH were restored to their initial resting levels. Continuous infusion of 0.1 μM acetylcholine caused marked and sustained increases in the flow of pancreatic juice and protein output. During the stimulation the tissue levels of phosphorus compounds remained unchanged, while the tissue pH was decreased slightly

  9. Atomic and electronic structure of exfoliated black phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Ryan J.; Topsakal, Mehmet; Jeong, Jong Seok; Wentzcovitch, Renata M.; Mkhoyan, K. Andre, E-mail: mkhoyan@umn.edu [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Low, Tony; Robbins, Matthew C.; Haratipour, Nazila; Koester, Steven J. [Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2015-11-15

    Black phosphorus, a layered two-dimensional crystal with tunable electronic properties and high hole mobility, is quickly emerging as a promising candidate for future electronic and photonic devices. Although theoretical studies using ab initio calculations have tried to predict its atomic and electronic structure, uncertainty in its fundamental properties due to a lack of clear experimental evidence continues to stymie our full understanding and application of this novel material. In this work, aberration-corrected scanning transmission electron microscopy and ab initio calculations are used to study the crystal structure of few-layer black phosphorus. Directly interpretable annular dark-field images provide a three-dimensional atomic-resolution view of this layered material in which its stacking order and all three lattice parameters can be unambiguously identified. In addition, electron energy-loss spectroscopy (EELS) is used to measure the conduction band density of states of black phosphorus, which agrees well with the results of density functional theory calculations performed for the experimentally determined crystal. Furthermore, experimental EELS measurements of interband transitions and surface plasmon excitations are also consistent with simulated results. Finally, the effects of oxidation on both the atomic and electronic structure of black phosphorus are analyzed to explain observed device degradation. The transformation of black phosphorus into amorphous PO{sub 3} or H{sub 3}PO{sub 3} during oxidation may ultimately be responsible for the degradation of devices exposed to atmosphere over time.

  10. Optical emission and mass spectroscopy of plasma processes in reactive DC pulsed magnetron sputtering of aluminium oxide

    Czech Academy of Sciences Publication Activity Database

    Novotný, Michal; Bulíř, Jiří; Pokorný, Petr; Bočan, Jiří; Fitl, Přemysl; Lančok, Ján; Musil, Jindřich

    2010-01-01

    Roč. 12, č. 3 (2010), 697-700 ISSN 1454-4164 R&D Projects: GA AV ČR IAA100100718; GA AV ČR KAN400100653; GA ČR GP202/09/P324 Institutional research plan: CEZ:AV0Z10100522 Keywords : reactive magnetron sputtering * alumina * plasma spectroscopy * mass spectroscopy * optical emission spectroscopy Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.412, year: 2010

  11. Atmospheric acidification of mineral aerosols: a source of bioavailable phosphorus for the oceans

    Directory of Open Access Journals (Sweden)

    A. Nenes

    2011-07-01

    Full Text Available Primary productivity of continental and marine ecosystems is often limited or co-limited by phosphorus. Deposition of atmospheric aerosols provides the major external source of phosphorus to marine surface waters. However, only a fraction of deposited aerosol phosphorus is water soluble and available for uptake by phytoplankton. We propose that atmospheric acidification of aerosols is a prime mechanism producing soluble phosphorus from soil-derived minerals. Acid mobilization is expected to be pronounced where polluted and dust-laden air masses mix. Our hypothesis is supported by the soluble compositions and reconstructed pH values for atmospheric particulate matter samples collected over a 5-yr period at Finokalia, Crete. In addition, at least tenfold increase in soluble phosphorus was observed when Saharan soil and dust were acidified in laboratory experiments which simulate atmospheric conditions. Aerosol acidification links bioavailable phosphorus supply to anthropogenic and natural acidic gas emissions, and may be a key regulator of ocean biogeochemistry.

  12. Anomalous Temperature Dependence in Metal-Black Phosphorus Contact.

    Science.gov (United States)

    Li, Xuefei; Grassi, Roberto; Li, Sichao; Li, Tiaoyang; Xiong, Xiong; Low, Tony; Wu, Yanqing

    2018-01-10

    Metal-semiconductor contact has been the performance limiting problem for electronic devices and also dictates the scaling potential for future generation devices based on novel channel materials. Two-dimensional semiconductors beyond graphene, particularly few layer black phosphorus, have attracted much attention due to their exceptional electronic properties such as anisotropy and high mobility. However, due to its ultrathin body nature, few layer black phosphorus-metal contact behaves differently than conventional Schottky barrier (SB) junctions, and the mechanisms of its carrier transport across such a barrier remain elusive. In this work, we examine the transport characteristic of metal-black phosphorus contact under varying temperature. We elucidated the origin of apparent negative SB heights extracted from classical thermionic emission model and also the phenomenon of metal-insulator transition observed in the current-temperature transistor characteristic. In essence, we found that the SB height can be modulated by the back-gate voltage, which beyond a certain critical point becomes so low that the injected carrier can no longer be described by the conventional thermionic emission theory. The transition from transport dominated by a Maxwell-Boltzmann distribution for the high energy tail states, to that of a Fermi distribution by low energy Fermi sea electrons, is the physical origin of the observed metal-insulator transition. We identified two distinctive tunneling limited transport regimes in the contact: vertical and longitudinal tunneling.

  13. Liming induces carbon dioxide (CO2) emission in PSB inoculated alkaline soil supplemented with different phosphorus sources.

    Science.gov (United States)

    Adnan, Muhammad; Shah, Zahir; Sharif, Muhammad; Rahman, Hidayatur

    2018-04-01

    Agricultural land is a major sink of global organic carbon (C). Its suitable management is crucial for improving C sequestration and reducing soil CO 2 emission. Incubation experiments were performed to assess the impact of phosphate solubilizing bacterial (PSB) inoculation (inoculated and uninoculated) and soil calcification (4.78, 10, 15, and 20% crushed CaCO 3 ) with phosphorus (P) sources [single superphosphate (SSP), rock phosphate (RP), farm yard manure (FYM), and poultry manure (PM)] in experiment 1 and with various rates of PM (4, 8, and 12 kg ha -1 ) in experiment 2 on cumulative soil respiration. These experiments were arranged in three factorial, complete randomize design (CRD) with three replications. Interactively, lime with P sources (at day 1 and 3) and lime with PSB (at day 1) significantly expedited soil respiration. Mainly, PSB inoculation, liming, PM fertilization, and its various rates significantly enhanced soil respiration with time over control/minimum in alkaline soil at all incubation periods. Higher CO 2 emission was detected in soil supplemented with organic P sources (PM and FYM) than mineral sources (SSP and RP). CO 2 emission was noted to increase with increasing PM content. Since liming intensified CO 2 discharge from soil, therefore addition of lime to an alkaline soil should be avoided; instead, integrated approaches must be adopted for P management in alkaline calcareous soils for climate-smart agriculture.

  14. Effects of phosphorus doping on structural and optical properties of silicon nanocrystals in a SiO2 matrix

    International Nuclear Information System (INIS)

    Hao, X.J.; Cho, E.-C.; Scardera, G.; Bellet-Amalric, E.; Bellet, D.; Shen, Y.S.; Huang, S.; Huang, Y.D.; Conibeer, G.; Green, M.A.

    2009-01-01

    Promise of Si nanocrystals highly depends on tailoring their behaviour through doping. Phosphorus-doped silicon nanocrystals embedded in a silicon dioxide matrix have been realized by a co-sputtering process. The effects of phosphorus-doping on the properties of Si nanocrystals are investigated. Phosphorus diffuses from P-P and/or P-Si to P-O upon high temperature annealing. The dominant X-ray photoelectron spectroscopy P 2p signal attributable to Si-P and/or P-P (130 eV) at 1100 o C indicates that the phosphorus may exist inside Si nanocrystals. It is found that existence of phosphorus enhances phase separation of silicon rich oxide and thereby Si crystallization. In addition, phosphorus has a considerable effect on the optical absorption and photoluminescence properties as a function of annealing temperature.

  15. Hole emission from Ge/Si quantum dots studied by time-resolved capacitance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kapteyn, C.M.A.; Lion, M.; Heitz, R.; Bimberg, D. [Technische Univ. Berlin (Germany). Inst. fuer Festkoerperphysik; Miesner, C.; Asperger, T.; Brunner, K.; Abstreiter, G. [Technische Univ. Muenchen, Garching (Germany). Walter-Schottky-Inst. fuer Physikalische Grundlagen der Halbleiterelektronik

    2001-03-01

    Emission of holes from self-organized Ge quantum dots (QDs) embedded in Si Schottky diodes is studied by time-resolved capacitance spectroscopy (DLTS). The DLTS signal is rather broad and depends strongly on the filling and detection bias conditions. The observed dependence is interpreted in terms of carrier emission from many-hole states of the QDs. The activation energies obtained from the DLTS measurements are a function of the amount of stored charge and the position of the Fermi level in the QDs. (orig.)

  16. 31P-NMR spectroscopy in measurements of physiological parameters and response to therapy of human melanoma xenografts

    International Nuclear Information System (INIS)

    Olsen, Dag Rune

    1999-01-01

    The aim of the study was to investigate whether ''31P-NMR spectroscopy can be utilized in prediction and monitoring of response to therapy or tumours. The specific aims were: 1) To investigate possible correlations between on the one hand bio energetics status, phospholipids resonance ratios, intracellular pH and phosphorus T 1 s and on the other hand tumour blood supply and oxygenation, tumour proliferation and necrotic fraction across tumour lines. 2) Reveal possible correlations between changes in tumour bio energetics status and phosphorus T 1 s and the changes in tumour blood flow, tumour oxygenation and necrotic fraction. 3) To investigate whether irradiation and hyperthermia treatment of tumours affect bio energetics status and phosphorus T 1 s. 4) To identify the tumour physiological factors that is effected by the treatment and influence the bio energetics status and phosphorus T 1 s. The results are presented in 8 papers with titles: 1)''31P-nuclear magnetic resonance spectroscopy in vivo of six human melanoma zeno graft lines: Tumour bio energetic status and blood supply. 2) ''31P NMR spectroscopy studies of phospholipid metabolism in human melanoma xenograft lines differing in rate of tumour cell proliferation. 3) ''31P-nuclear magnetic resonance spectroscopy in vivo of four human melanoma xenograft lines: Spin-lattice relaxation times. 4) Effect of melanin on phosphorus T 1 s in human melanoma xenografts studied by ''31P MRS 5) Spin-lattice relaxation time of inorganic phosphate in human tumour xenografts measured in vivo by ''31P-magnetic resonance spectroscopy influence of oxygen tension. 6) Effects of hyperthermia on bio energetic status and phosphorus T 1 s in human melanoma xenografts monitored by ''31P-MRS. 7) Monitoring of tumour reoxygenation following irradiation by ''31P magnetic resonance spectroscopy an experimental study of human melanoma xenografts. 8) Radiation-induced changes in phosphorus T 1 values in human melanoma xenografts studied

  17. [Effects of phosphorus sources on phosphorus fractions in rhizosphere soil of wild barley genotypes with high phosphorus utilization efficiency].

    Science.gov (United States)

    Cai, Qiu-Yan; Zhang, Xi-Zhou; Li, Ting-Xuan; Chen, Guang-Deng

    2014-11-01

    High P-efficiency (IS-22-30, IS-22-25) and low P-efficiency (IS-07-07) wild barley cultivars were chosen to evaluate characteristics of phosphorus uptake and utilization, and properties of phosphorus fractions in rhizosphere and non-rhizosphere in a pot experiment with 0 (CK) and 30 mg P · kg(-1) supplied as only Pi (KH2PO4), only Po (phytate) or Pi + Po (KH2PO4+ phytate). The results showed that dry matter and phosphorus accumulation of wild barley in the different treatments was ranked as Pi > Pi + Po > Po > CK. In addition, dry matter yield and phosphorus uptake of wild barley with high P-efficiency exhibited significantly greater than that with low P-efficiency. The concentration of soil available phosphorus was significantly different after application of different phosphorus sources, which was presented as Pi > Pi + Po > Po. The concentration of soil available phosphorus in high P-efficiency wild barley was significantly higher than that of low P-efficiency in the rhizosphere soil. There was a deficit in rhizosphere available phosphorus of high P-efficiency wild barley, especially in Pi and Pi+Po treatments. The inorganic phosphorus fractions increased with the increasing Pi treatment, and the concentrations of inorganic phosphorus fractions in soil were sorted as follows: Ca10-P > O-P > Fe-P > Al-P > Ca2-P > Ca8-P. The contents of Ca2-P and Ca8-P for high P-efficiency wild barley showed deficits in rhizosphere soil under each phosphorus source treatment. In addition, enrichment of Al-P and Fe-P was observed in Pi treatment in rhizosphere soil. The concentrations of organic phosphorus fractions in soil were sorted as follows: moderate labile organic phosphorus > moderate resistant, resistant organic phosphorus > labile organic phosphorus. The labile and moderate labile organic phosphorus enriched in rhizosphere soil and the greatest enrichment appeared in Pi treatment. Furthermore, the concentrations of moderate resistant organic phosphorus and resistant

  18. Experimental analysis of the Schottky barrier height of metal contacts in black phosphorus field-effect transistors

    Science.gov (United States)

    Chang, Hsun-Ming; Fan, Kai-Lin; Charnas, Adam; Ye, Peide D.; Lin, Yu-Ming; Wu, Chih-I.; Wu, Chao-Hsin

    2018-04-01

    Compared to graphene and MoS2, studies on metal contacts to black phosphorus (BP) transistors are still immature. In this work, we present the experimental analysis of titanium contacts on BP based upon the theory of thermionic emssion. The Schottky barrier height (SBH) is extracted by thermionic emission methods to analyze the properties of Ti-BP contact. To examine the results, the band gap of BP is extracted followed by theoretical band alignment by Schottky-Mott rule. However, an underestimated SBH is found due to the hysteresis in electrical results. Hence, a modified SBH extraction for contact resistance that avoids the effects of hysteresis is proposed and demonstrated, showing a more accurate SBH that agrees well with theoretical value and results of transmission electron microscopy and energy-dispersive x-ray spectroscopy.

  19. Remote gas analysis of aircraft exhausts using FTIR-emission-spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Heland, J.; Schaefer, K. [Fraunhofer Inst. for Atmospheric Environmental Research, Garmisch-Partenkirchen (Germany)

    1997-12-31

    FITR emission spectroscopy as a remote sensing multi-component analyzing technique was investigated to determine the composition of aircraft exhausts at ground level. A multi-layer radiative transfer interpretation software based on a line-by-line computer algorithm using the HITRAN data base was developed. Measurements were carried out with different engine types to determine the traceable gas species and their detection limits. Finally validation measurements were made to compare the results of the system to those of conventional equipment. (author) 8 refs.

  20. Remote gas analysis of aircraft exhausts using FTIR-emission-spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Heland, J; Schaefer, K [Fraunhofer Inst. for Atmospheric Environmental Research, Garmisch-Partenkirchen (Germany)

    1998-12-31

    FITR emission spectroscopy as a remote sensing multi-component analyzing technique was investigated to determine the composition of aircraft exhausts at ground level. A multi-layer radiative transfer interpretation software based on a line-by-line computer algorithm using the HITRAN data base was developed. Measurements were carried out with different engine types to determine the traceable gas species and their detection limits. Finally validation measurements were made to compare the results of the system to those of conventional equipment. (author) 8 refs.

  1. Preparation of phosphorus targets using the compound phosphorus nitride

    International Nuclear Information System (INIS)

    Maier-Komor, P.

    1987-01-01

    Commercially available phosphorus nitride (P 3 N 5 ) shows a high oxygen content. Nevertheless, this material is attractive for use as phosphorus targets in experiments where red phosphorus would disappear due to its high vapor pressure and where a metal partner in the phosphide must be excluded due to its high atomic number. Methods are described to produce phosphorus nitride targets by vacuum evaporation condensation. (orig.)

  2. Lithium-ion battery electrolyte emissions analyzed by coupled thermogravimetric/Fourier-transform infrared spectroscopy

    Science.gov (United States)

    Bertilsson, Simon; Larsson, Fredrik; Furlani, Maurizio; Albinsson, Ingvar; Mellander, Bengt-Erik

    2017-10-01

    In the last few years the use of Li-ion batteries has increased rapidly, powering small as well as large applications, from electronic devices to power storage facilities. The Li-ion battery has, however, several safety issues regarding occasional overheating and subsequent thermal runaway. During such episodes, gas emissions from the electrolyte are of special concern because of their toxicity, flammability and the risk for gas explosion. In this work, the emissions from heated typical electrolyte components as well as from commonly used electrolytes are characterized using FT-IR spectroscopy and FT-IR coupled with thermogravimetric (TG) analysis, when heating up to 650 °C. The study includes the solvents EC, PC, DEC, DMC and EA in various single, binary and ternary mixtures with and without the LiPF6 salt, a commercially available electrolyte, (LP71), containing EC, DEC, DMC and LiPF6 as well as extracted electrolyte from a commercial 6.8 Ah Li-ion cell. Upon thermal heating, emissions of organic compounds and of the toxic decomposition products hydrogen fluoride (HF) and phosphoryl fluoride (POF3) were detected. The electrolyte and its components have also been extensively analyzed by means of infrared spectroscopy for identification purposes.

  3. n-type diamond growth by phosphorus doping on (0 0 1)-oriented surface

    International Nuclear Information System (INIS)

    Kato, Hiromitsu; Makino, Toshiharu; Yamasaki, Satoshi; Okushi, Hideyo

    2007-01-01

    The properties of phosphorus incorporation for n-type doping of diamond are discussed and summarized. Doping of (0 0 1)-oriented diamond is introduced and compared with results achieved on (1 1 1) diamond. This review describes detailed procedures and conditions of plasma-enhanced chemical vapour deposition (CVD) growth and characteristics of electrical properties of phosphorus-doped diamond. The phosphorus incorporation was characterized by SIMS analysis including mapping. n-type conductivity is evaluated by Hall-effect measurements over a temperature regime of 300-1000 K. The crystal perfection of (0 0 1)-oriented n-type diamond is also evaluated by x-ray diffraction, Raman spectroscopy, reflection high-energy electron diffraction and cathodoluminescence analyses. The results show that phosphorus atoms are incorporated into the diamond network during (0 0 1) CVD diamond growth and that phosphorus acts as a donor as in (1 1 1)-oriented diamond. This result eliminates the restriction on substrate orientation, which had previously created a bottleneck in the development of diamond electronic devices. (review article)

  4. Further studies on the lithium phosphorus oxynitride solid electrolyte

    International Nuclear Information System (INIS)

    Pichonat, Tristan; Lethien, Christophe; Tiercelin, Nicolas; Godey, Sylvie; Pichonat, Emmanuelle; Roussel, Pascal; Colmont, Marie; Rolland, Paul Alain

    2010-01-01

    First step in the way to the fabrication of an all-solid microbattery for autonomous wireless sensor node, amorphous thin solid films of lithium phosphorus oxynitride (LiPON) were prepared by radio-frequency sputtering of a mixture target of P 2 O 5 /Li 2 O in ambient nitrogen atmosphere. The morphology, composition, and ionic conductivity were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and A.C. impedance spectroscopy. With a thickness of 1.4 μm, the obtained LiPON amorphous layer provided an ionic conductivity close to 6 x 10 -7 S cm -1 at room temperature. MicroRaman UV spectroscopy study was successfully carried out for the first time on LiPON thin films to complete the characterization and bring further information on LiPON structure.

  5. Grain boundary phosphorus segregation under thermal aging in low alloy steels

    International Nuclear Information System (INIS)

    Nakata, Hayato; Fujii, Katsuhiko; Fukuya, Koji; Kasada, Ryuta; Kimura, Akihiko

    2007-01-01

    Intergranular embrittlement due to grain boundary segregation of phosphorus is recognized as one of the potential degradation factors in irradiated reactor low alloy steels at high neutron fluence. In this study, low alloy steels thermally aged at 400-500degC were investigated to evaluate the correlation between phosphorus segregation and intergranular embrittlement. Phosphorus segregation determined using Auger electron spectroscopy increased after thermal aging above 450degC and was in good agreement with the calculated value based on McLean's model. No influence of thermal aging on tensile properties or hardness was observed. The ductile brittle transition temperature determined using a one-third size Charpy impact test increased at a P/Fe peak ratio of 0.14. These results indicated that there is a threshold level of phosphorus segregation for non-hardening embrittlement. DBTT increased with the proportion of intergranular fracture, so this result shows that there is a relationship between DBTT and the properties of intergranular fracture. The fracture stress decreases due to non-hardening embrittlement on the thermally aged material with high proportion of intergranular fracture. (author)

  6. Metastable argon atom density in complex argon/acetylene plasmas determined by means of optical absorption and emission spectroscopy

    International Nuclear Information System (INIS)

    Sushkov, Vladimir; Herrendorf, Ann-Pierra; Hippler, Rainer

    2016-01-01

    Optical emission and absorption spectroscopy has been utilized to investigate the instability of acetylene-containing dusty plasmas induced by growing nano-particles. The density of Ar(1s 5 ) metastable atoms was derived by two methods: tunable diode laser absorption spectroscopy and with the help of the branching ratio method of emitted spectral lines. Results of the two techniques agree well with each other. The density of Ar(1s 3 ) metastable atoms was also measured by means of optical emission spectroscopy. The observed growth instability leads to pronounced temporal variations of the metastable and other excited state densities. An analysis of optical line ratios provides evidence for a depletion of free electrons during the growth cycle but no indication for electron temperature variations. (paper)

  7. Chemical states of piled-up phosphorus and arsenic atoms at the SiO2/Si interface

    International Nuclear Information System (INIS)

    Yoshimura, Yusuke; Ono, Kanta; Fujioka, Hiroshi; Hayakawa, Shinjiro; Sato, Yoshiyuki; Uematsu, Masashi; Baba, Yuji; Hirose, Kazuyuki; Oshima, Masaharu

    1999-01-01

    We have investigated the positions of the piled-up phosphorus atoms at the SiO 2 /Si interface using the extended X-ray absorption fine structure (EXAFS) and X-ray photoelectron spectroscopy (XPS). The EXAFS and XPS data can be well explained on the assumption that the piled-up arsenic atoms exist at the tetrahedral sites. On the contrary, phosphorus atoms exist not at the tetrahedral sites but at the denser sites. The depth profile measurements of XPS have revealed that the piled-up arsenic and phosphorus atoms exist within 20A from the interface. (author)

  8. Isotope analysis by emission spectroscopy; Analyse isotopique par spectroscopie d'emission

    Energy Technology Data Exchange (ETDEWEB)

    Artaud, J; Gerstenkorn, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Blaise, J [Centre National de la Recherche Scientifique (CNRS), Lab. Aime Cotton, 92 - Meudon-Bellevue (France)

    1959-07-01

    Quantitative analysis of isotope mixtures by emission spectroscopy is resulting from the phenomenon called 'isotope shift', say from the fact that spectral lines produced by a mixture of isotopes of a same element are complex. Every spectral line is, indeed, resulting from several lines respectively corresponding to each isotope. Then isotopic components are near one to others, and their separation is effected by means of Fabry-Perot calibration standard: the apparatus allowing to measure abundances is the Fabry-Perot photo-electric spectrometer, designed in 1948 by MM. JACQUINOT and DUFOUR. This method has been used to make abundance determination in the case of helium, lithium, lead and uranium. In the case of lithium, the utilised analysis line depends on the composition of examined isotopic mixture. For mixtures containing 7 to 93 pour cent of one of isotopes of lithium, this line is the lithium blue line: {lambda} = 4603 angstrom. In other cases the red line {lambda} = 6707 angstrom is preferable, though it allows to do easily nothing but relative determinations. Helium shows no particular difficulty and the analysis line selected was {lambda} = 6678 angstrom. For lead the line {lambda} = 5201 angstrom gives the possibility to determine the isotope abundance for the four isotopes of lead notwithstanding the presence of hyperfine structure of {sup 207}Pb. For uranium, line {lambda} 5027 angstrom is used, and this method allows to determine the composition of isotope mixtures, the content of which in {sup 235}U may shorten to 0,1 per cent. Relative precision is about 2 per cent for contents in {sup 235}U over 1 per cent. For lower contents, this line {lambda} = 5027 angstrom will allow relative measures when using previously dosed mixtures. (author) [French] L'analyse quantitative des melanges isotopiques par spectroscopie d'emission doit son existence au phenomene appele 'deplacement isotopique', c'est-a-dire au fait que les raies spectrales emises par un

  9. Electrolytic cell-free 57Co deposition for emission Mössbauer spectroscopy

    Science.gov (United States)

    Zyabkin, Dmitry V.; Procházka, Vít; Miglierini, Marcel; Mašláň, Miroslav

    2018-05-01

    We have developed a simple, inexpensive and efficient method for an electrochemical preparation of samples for emission Mössbauer spectroscopy (EMS) and Mössbauer sources. The proposed electrolytic deposition procedure does not require any special setup, not even an electrolytic cell. It utilizes solely an electrode with a droplet of electrolyte on its surface and the second electrode sunk into the droplet. Its performance is demonstrated using two examples, a metallic glass and a Cu stripe. We present a detailed description of the deposition procedure and resulting emission Mössbauer spectra for both samples. In the case of a Cu stripe, we have performed EMS measurements at different stages of heat-treatment, which are required for the production of Mössbauer sources with the copper matrix.

  10. Phosphorus addition mitigates N2O and CH4 emissions in N-saturated subtropical forest, SW China

    Directory of Open Access Journals (Sweden)

    L. Yu

    2017-06-01

    Full Text Available Chronically elevated nitrogen (N deposition has led to severe nutrient imbalance in forest soils. Particularly in tropical and subtropical forest ecosystems, increasing N loading has aggravated phosphorus (P limitation of biomass production, and has resulted in elevated emissions of nitrous oxide (N2O and reduced uptake of methane (CH4, both of which are important greenhouse gases. Yet, the interactions of N and P and their effects on greenhouse gas emissions remain elusive. Here, we report N2O and CH4 emissions together with soil N and P data for a period of 18 months following a single P addition (79 kg P ha−1, as NaH2PO4 powder to an N-saturated, Masson pine-dominated forest soil at TieShanPing (TSP, Chongqing, south-western (SW China. We observed a significant decline in both nitrate (NO3− concentrations in soil water (5 and 20 cm depths and in soil N2O emissions, following P application. We hypothesise that enhanced N uptake by plants in response to P addition, resulted in less available NO3− for denitrification. By contrast to most other forest ecosystems, TSP is a net source of CH4. P addition significantly decreased CH4 emissions and turned the soil from a net source into a net sink. Based on our observation and previous studies in South America and China, we believe that P addition relieves N inhibition of CH4 oxidation. Within the 1.5 years after P addition, no significant increase of forest growth was observed and P stimulation of forest N uptake by understorey vegetation remains to be confirmed. Our study indicates that P fertilisation of N-saturated, subtropical forest soils may mitigate N2O and CH4 emissions, in addition to alleviating nutrient imbalances and reducing losses of N through NO3− leaching.

  11. Combined equilibrium and non-equilibrium phosphorus segregation to grain boundaries in a 2.25Cr1Mo steel

    International Nuclear Information System (INIS)

    Song, S.-H.; Shen, D.-D.; Yuan, Z.-X.; Liu, J.; Xu, T.-D.; Weng, L.-Q.

    2003-01-01

    Grain boundary segregation of phosphorus in a P-doped 2.25Cr1Mo steel during ageing at 540 deg. C after quenching from 980 deg. C is examined by Auger electron spectroscopy. The segregation is a combined effect of equilibrium segregation and non-equilibrium segregation. The effect of phosphorus non-equilibrium segregation is to enhance the kinetics of its equilibrium segregation

  12. Sustainable Phosphorus Measures: Strategies and Technologies for Achieving Phosphorus Security

    Directory of Open Access Journals (Sweden)

    Stuart White

    2013-01-01

    Full Text Available Phosphorus underpins the world’s food systems by ensuring soil fertility, maximising crop yields, supporting farmer livelihoods and ultimately food security. Yet increasing concerns around long-term availability and accessibility of the world’s main source of phosphorus—phosphate rock, means there is a need to investigate sustainable measures to buffer the world’s food systems against the long and short-term impacts of global phosphorus scarcity. While the timeline of phosphorus scarcity is contested, there is consensus that more efficient use and recycling of phosphorus is required. While the agricultural sector will be crucial in achieving this, sustainable phosphorus measures in sectors upstream and downstream of agriculture from mine to fork will also need to be addressed. This paper presents a comprehensive classification of all potential phosphorus supply- and demand-side measures to meet long-term phosphorus needs for food production. Examples range from increasing efficiency in the agricultural and mining sector, to technologies for recovering phosphorus from urine and food waste. Such measures are often undertaken in isolation from one another rather than linked in an integrated strategy. This integrated approach will enable scientists and policy-makers to take a systematic approach when identifying potential sustainable phosphorus measures. If a systematic approach is not taken, there is a risk of inappropriate investment in research and implementation of technologies and that will not ultimately ensure sufficient access to phosphorus to produce food in the future. The paper concludes by introducing a framework to assess and compare sustainable phosphorus measures and to determine the least cost options in a given context.

  13. Simultaneous denitrification and phosphorus removal by Agrobacterium sp. LAD9 under varying oxygen concentration.

    Science.gov (United States)

    Ma, Tao; Chen, Qian; Gui, Mengyao; Li, Can; Ni, Jinren

    2016-04-01

    Although efficient aerobic denitrification has received increasing attention, few studies have been made on simultaneous denitrification and phosphorus removal (SDPR) under aerobic condition. In this study, SDPR by an efficient aerobic denitrifier, Agrobacterium sp. LAD9, was firstly demonstrated. High nitrate and phosphorus removal rates of 7.50 and 1.02 mg L(-1) h(-1) were achieved in wide range of O2 concentration from 5.92 to 20.02 mg L(-1). The N2O production would be inhibited as O2 concentration exceeded 11.06 mg L(-1), while the phosphorus removal efficiency would be generally improved with increasing O2 concentration. (15)N mass spectrometry revealed that nitrogen removal accorded with the typical aerobic denitrification pathway, while (31)P nuclear magnetic resonance spectroscopy ((31)P NMR) indicated the fate of phosphorus to cells, extracellular polymeric substances (EPS), and polyphosphate (poly-P) of the denitrifier. EPS acted as a reservoir of phosphorus and the transformation of poly-P was dynamic and depended on initial orthophosphate (ortho-P) content. The aerobic SDPR would greatly simplify the conventional wastewater treatment processes which required separated considerations of nitrogen and phosphorus removal.

  14. The Internal Recycle Reactor Enhances Porous Calcium Silicate Hydrates to Recover Phosphorus from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Wei Guan

    2017-01-01

    Full Text Available In this experiment, the porous calcium silicate hydrates (P-CSHs were prepared via a hydrothermal method and then modified by polyethylene glycol (PEG. The modified P-CSHs combined with an internal recycle reactor could successfully recover the phosphorus from electroplating wastewater. The modified P-CSHs were characterized by X-ray diffraction (XRD, N2 adsorption-desorption isotherms, and Fourier transform infrared spectroscopy (FT-IR. After compared with different samples, the modified P-CSHs-PEG2000 sample had larger specific surface area of 87.48 m2/g and higher pore volume of 0.33 cm3/g, indicating a high capacity for phosphorus recovery. In the process of phosphorus recovery, the pH value of solution was increased to 9.5, which would enhance the recovery efficiency of phosphorus. The dissolution rate of Ca2+ from P-CSH-PEG2000 was fast, which was favorable for phosphorus precipitation and phosphorus recovery. The effects of initial concentration of phosphorus, P-CSHs-PEG2000 dosage, and stirring speed on phosphorus recovery were analyzed, so the optimal operation conditions for phosphorus recovery were obtained. The deposition was analyzed by XRD, N2 adsorption-desorption, and SEM techniques; it was indicated that the pore volume and surface area of the P-CSHs-PEG2000 were significantly reduced, and the deposition on the surface of P-CSHs-PEG2000 was hydroxyapatite.

  15. MEASUREMENT OF AMMONIA EMISSIONS FROM MECHANICALLY VENTILATED POULTRY HOUSES USING MULTIPATH TUNABLE DIODE LASER SPECTROSCOPY

    Science.gov (United States)

    Ammonia emissions from mechanically ventilated poultry operations are an important environmental concern. Open Path Tunable Diode Laser Absorption Spectroscopy has emerged as a robust real-time method for gas phase measurement of ammonia concentrations in agricultural settings. ...

  16. Nitrous oxide emissions from soil amended with low-phosphorus broiler litter

    Science.gov (United States)

    Regions of the United States with a high concentration of poultry farms have soils with excess nitrogen (N) and phosphorus (P) far beyond the agronomic requirement of crops because of recurrent land application of broiler litter. A new waste treatment technology developed by USDA-ARS, called “Quick ...

  17. Impacts of European livestock production: nitrogen, sulphur, phosphorus and greenhouse gas emissions, land-use, water eutrophication and biodiversity

    International Nuclear Information System (INIS)

    Leip, Adrian; Grizzetti, Bruna; Weiss, Franz; Billen, Gilles; Garnier, Josette; Lassaletta, Luis; Reis, Stefan; Sutton, Mark A; Simpson, David; De Vries, Wim; Westhoek, Henk

    2015-01-01

    Livestock production systems currently occupy around 28% of the land surface of the European Union (equivalent to 65% of the agricultural land). In conjunction with other human activities, livestock production systems affect water, air and soil quality, global climate and biodiversity, altering the biogeochemical cycles of nitrogen, phosphorus and carbon. Here, we quantify the contribution of European livestock production to these major impacts. For each environmental effect, the contribution of livestock is expressed as shares of the emitted compounds and land used, as compared to the whole agricultural sector. The results show that the livestock sector contributes significantly to agricultural environmental impacts. This contribution is 78% for terrestrial biodiversity loss, 80% for soil acidification and air pollution (ammonia and nitrogen oxides emissions), 81% for global warming, and 73% for water pollution (both N and P). The agriculture sector itself is one of the major contributors to these environmental impacts, ranging between 12% for global warming and 59% for N water quality impact. Significant progress in mitigating these environmental impacts in Europe will only be possible through a combination of technological measures reducing livestock emissions, improved food choices and reduced food waste of European citizens. (letter)

  18. Mechanical design of the two dimensional beam emission spectroscopy diagnostics on mast

    Energy Technology Data Exchange (ETDEWEB)

    Kiss, Istvan Gabor, E-mail: kiss.istvan.gabor@rmki.kfki.hu [Association EURATOM, KFKI-RMKI, P.O. Box 49, H-1525 Budapest (Hungary); Meszaros, Botond; Dunai, Daniel; Zoletnik, Sandor; Krizsanoczi, Tibor [Association EURATOM, KFKI-RMKI, P.O. Box 49, H-1525 Budapest (Hungary); Field, Anthony R.; Gaffka, Rob [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)

    2011-10-15

    A two dimensional beam emission spectroscopy (BES) system optimized for density turbulence measurements has recently been installed on the MAST tokamak. This system observes the emission of a Deuterium heating beam using a rotatable mirror to view from the plasma centre to the outboard edge (0.7-1.5 m), although the optics is optimized for core region (1.2 m). The beam is imaged onto a 4x8 pixel Avalanche Photodiode (APD) array detector, enabling measurements with 1 MHz bandwidth at photon-flux level of few times 10{sup 11} photons/s. This article will present the mechanical design of MAST BES equipment with special emphasis on its in-vessel components.

  19. Spectroscopy of optically selected BL Lac objects and their γ-ray emission

    Energy Technology Data Exchange (ETDEWEB)

    Sandrinelli, A.; Treves, A.; Farina, E. P.; Landoni, M. [Università degli Studi dell' Insubria, Via Valleggio 11, I-22100 Como (Italy); Falomo, R. [INAF-Osservatorio Astronomico di Padova, Vicolo dell Osservatorio 5, I-35122 Padova (Italy); Foschini, L.; Sbarufatti, B., E-mail: angela.sandrinelli@brera.inaf.it [INAF-Osservatorio Astronomico di Brera, Via Emilio Bianchi 46, I-23807 Merate (Italy)

    2013-12-01

    We present Very Large Telescope optical spectroscopy of nine BL Lac objects of unknown redshift belonging to the list of optically selected radio-loud BL Lac candidates. We explore their spectroscopic properties and possible link with gamma-ray emission. From the new observations we determine the redshifts of four objects from faint emission lines or from absorption features of their host galaxies. In three cases we find narrow intervening absorptions from which a lower limit to the redshift is inferred. For the remaining two featureless sources, lower limits to the redshift are deduced from the absence of spectral lines. A search for γ counterpart emission shows that six out of the nine candidates are Fermi γ-ray emitters and we find two new detections. Our analysis suggests that most of the BL Lac objects still lacking redshift information are most likely located at high redshifts.

  20. Spectroscopy stepping stones

    International Nuclear Information System (INIS)

    Hammer, M.R.; Sturman, B.T.

    2003-01-01

    Determining the elemental composition of samples has long been a basic task of analytical science. Some very powerful and convenient approaches are based on the wavelength-specific absorption or emission of light by gas-phase atoms. Techniques briefly described as examples of analytical atomic spectrometry include atomic emission and absorption spectroscopy, inductively coupled plasma emission and mass spectroscopy and laser induced breakdown spectrometry

  1. End point detection in ion milling processes by sputter-induced optical emission spectroscopy

    International Nuclear Information System (INIS)

    Lu, C.; Dorian, M.; Tabei, M.; Elsea, A.

    1984-01-01

    The characteristic optical emission from the sputtered material during ion milling processes can provide an unambiguous indication of the presence of the specific etched species. By monitoring the intensity of a representative emission line, the etching process can be precisely terminated at an interface. Enhancement of the etching end point is possible by using a dual-channel photodetection system operating in a ratio or difference mode. The installation of the optical detection system to an existing etching chamber has been greatly facilitated by the use of optical fibers. Using a commercial ion milling system, experimental data for a number of etching processes have been obtained. The result demonstrates that sputter-induced optical emission spectroscopy offers many advantages over other techniques in detecting the etching end point of ion milling processes

  2. Phosphorus recovery as struvite from eutropic waters by XDA-7 resin.

    Science.gov (United States)

    Li, Huanwen; Ye, Zhiping; Lin, Ying; Wang, Fengying

    2012-01-01

    Phosphorus releases into aquatic environment and its subsequent contribution to eutrophication have resulted in a widespread global pollution issue. However, phosphorus is a non-renewable source. The potential supplies of phosphorus are decreasing worldwide. Therefore, removal and recovery of phosphorus from the eutropic waters is important, emergent and necessary. In this research, experiments for recovering phosphate from eutropic waters by anion exchange combined with struvite precipitation were conducted. The results indicated that the prepared XDA-7 resin was an effective adsorbent for phosphate. The adsorption isotherm of XDA-7 resin was found to be a modified Freundlich type. The maximum phosphate adsorption (20.9 mg/g) occurred in the pH range of 6.0-8.0. Phosphate adsorbed on the XDA-7 resin was effectively desorbed with 8% NaCl solution, and the resin was able to be regenerated with 3% NaClO and 4% NaOH solutions. Phosphate desorbed from the resin was recovered as magnesium ammonium phosphate (struvite). The obtained struvite was analyzed by acid dissolution method, scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The struvite precipitate was found to be 75.8% in purity, a high-value fertilizer.

  3. Inductively coupled plasma for atomic emission spectroscopy at the Savannah River Plant

    International Nuclear Information System (INIS)

    Coleman, J.T.

    1986-01-01

    The Savannah River Plant atomic emission spectroscopy laboratory has been in operation for over 30 years. Routine analytical methods and instrumentation are being replaced with current technology. Laboratory renovation will include the installation of contained dual excitation sources (inductively coupled plasma and d-c arc) with a direct reading spectrometer. The instrument will be used to provide impurity analyses of plutonium, uranium, and other nuclear fuel cycle materials

  4. Mid-infrared, long wave infrared (4-12 μm) molecular emission signatures from pharmaceuticals using laser-induced breakdown spectroscopy (LIBS).

    Science.gov (United States)

    Yang, Clayton S-C; Brown, Ei E; Kumi-Barimah, Eric; Hommerich, Uwe H; Jin, Feng; Trivedi, Sudhir B; Samuels, Alan C; Snyder, A Peter

    2014-01-01

    In an effort to augment the atomic emission spectra of conventional laser-induced breakdown spectroscopy (LIBS) and to provide an increase in selectivity, mid-wave to long-wave infrared (IR), LIBS studies were performed on several organic pharmaceuticals. Laser-induced breakdown spectroscopy signature molecular emissions of target organic compounds are observed for the first time in the IR fingerprint spectral region between 4-12 μm. The IR emission spectra of select organic pharmaceuticals closely correlate with their respective standard Fourier transform infrared spectra. Intact and/or fragment sample molecular species evidently survive the LIBS event. The combination of atomic emission signatures derived from conventional ultraviolet-visible-near-infrared LIBS with fingerprints of intact molecular entities determined from IR LIBS promises to be a powerful tool for chemical detection.

  5. Calcium and phosphorus determination in bones of low value fishes, Sardinella longiceps (Valenciennes and Trichiurus savala (Cuvier, from Parangipettai, Southeast Coast of India

    Directory of Open Access Journals (Sweden)

    Logesh AR

    2012-05-01

    Full Text Available Objective: To investigate calcium and phosphorus levels in the bones of low value fishes Sardinella longiceps (oil sardine and Trichiurus savala (ribbon fish. Methods: Bones and skeletal remains were subjected to alkaline-alcohol treatment for specified period of time and were then dried and pulverized. Calcium and phosphorus levels were determined by both volumetric and instrumental methods using atomic absorption spectroscopy. Results: Volumetric analysis of calcium and phosphorus were 28.98% and 14.2% in oil sardine; 24.2% and 11.6% in ribbon fish respectively. Atomic absorption spectroscopy analysis of calcium and phosphorus were 32.73% and 17.2% for oil sardine and 27.17% and 10.83% for ribbon fish respectively. Protein level was 4.82% in oil sardine and 3.97% in ribbon fishes. Conclusions: The findings of the present study revealed that sardine bones are rich in calcium and will be utilized for the production of calcium powder to treat osteoporosis.

  6. Ballistic electron emission spectroscopy on Ag/Si devices

    Energy Technology Data Exchange (ETDEWEB)

    Bannani, A; Bobisch, C A; Matena, M; Moeller, R [Department of Physics, Center for Nanointegration Duisburg-Essen, University of Duisburg-Essen, 47048 Duisburg (Germany)], E-mail: amin.bannani@uni-due.de

    2008-09-17

    In this work we report on ballistic electron emission spectroscopy (BEES) studies on epitaxial layers of silver grown on silicon surfaces, with either a Si(111)-(7 x 7) or Si(100)-(2 x 1) surface reconstruction. The experiments were done at low temperature and in ultra-high vacuum (UHV). In addition, BEES measurements on polycrystalline Ag films grown on hydrogen-terminated H:Si(111)-(1 x 1) and H:Si(100)-(2 x 1) surfaces were performed. The Schottky barrier heights were evaluated by BEES. The results are compared to the values for the barrier height reported for macroscopic Schottky diodes. We show that the barrier heights for the epitaxial films substantially differ from the values measured on polycrystalline Ag films, suggesting a strong effect of the interface on the barrier height.

  7. Preparation, flame retardancy and thermal behavior of a novel UV-curable coating containing phosphorus and nitrogen

    International Nuclear Information System (INIS)

    Xing Weiyi; Song Lei; Lv Pin; Jie Ganxin; Wang Xin; Lv Xiaoqi; Hu Yuan

    2010-01-01

    A novel phosphorus monomer, 2,2-dimethyl-1,3-propanediol acryloyloxyethyl phosphate (DPHA), has been synthesized through phosphorus oxychloride reacting with neopentyl glycol and 2-hydroxyethyl acrylate (HEA). Its structure was characterized by Fourier transform infrared spectroscopy (FTIR), 1 H nuclear magnetic resonance spectroscopy ( 1 H NMR) and 31 P nuclear magnetic resonance spectroscopy ( 31 P NMR). A series of UV-curable resins were manufactured by blending DPHA with triglycidyl isocyanurate acrylate (TGICA) at different weight ratio. The fire performance was examined by Microscale Combustion Calorimetry (MCC). The results obtained from MCC indicated that the addition of DPHA to TGICA decreased the peak heat release rate (PHRR), heat release capacity (HRC) and total heat of combustion (THC). The char residues of the composites were observed by scanning electron microscopy (SEM). The thermal decomposition behavior of DPHA/TGICA composites was characterized by using thermogravimetric analysis/infrared spectrometry (TGA-IR). The test results indicated that when the weight ratio of DPHA: TGICA = 1/1, the onset temperature of the composite was highest and the largest char residue at 700 deg. C was observed. The change of chemical structure during the thermal degradation process was monitored by real-time FTIR analysis. TGA-IR results indicated that the evolved products were CO, CO 2 , water, NH 3 , carbonyl, phosphorus oxides and aromatic compounds according to the temperature of onset formation.

  8. Zero-field optical magnetic resonance study of phosphorus donors in 28-silicon

    Science.gov (United States)

    Morse, Kevin J.; Dluhy, Phillip; Huber, Julian; Salvail, Jeff Z.; Saeedi, Kamyar; Riemann, Helge; Abrosimov, Nikolay V.; Becker, Peter; Pohl, Hans-Joachim; Simmons, S.; Thewalt, M. L. W.

    2018-03-01

    Donor spins in silicon are some of the most promising qubits for upcoming solid-state quantum technologies. The nuclear spins of phosphorus donors in enriched silicon have among the longest coherence times of any solid-state system as well as simultaneous high fidelity qubit initialization, manipulation, and readout. Here we characterize the phosphorus in silicon system in the regime of "zero" magnetic field, where a singlet-triplet spin clock transition can be accessed, using laser spectroscopy and magnetic resonance methods. We show the system can be optically hyperpolarized and has ˜10 s Hahn echo coherence times, even for applied static magnetic fields below Earth's field.

  9. Investigation of metal ions in fusion plasmas using emission spectroscopy

    International Nuclear Information System (INIS)

    Tale, I.

    2005-01-01

    Full text: The Latvian and Portugal Associations are performing development of advanced plasma - facing system using the liquid metal limiter. The objectives of this project require study of the influence of the liquid metal limiter on the main plasma parameters, including concentration of evaporated metal atoms in plasma. The fusion plasmas are related to the dense hot plasmas. The required average ion temperature according to the ITER project (International Thermonuclear Experimental Reactor) is 8,0 keV (9,3 x 10 7 0 K), the average electron temperature - 8,9 keV (1,04 x 10 8 0 K). Plasma temperature operated in the research tokamak ISSTOK, involved in testing of liquid metal limiter concept is considerably less, being of order of 10 50 K. The ionization degree of metal atoms considerably depends on the plasma ion temperature. Density of metal vapours in plasma can be estimated using the following two spectroscopic methods: The fluorescence of the multiple ionised metal ions in steady state concentration; The charge exchange emission during ionisation of evaporated metal ions. In the first step of development of testing system of metal vapours the equipment and instrumentation for charge exchange spectroscopy of Ga and In has been elaborated taking into account the following features of plasma emission. The Ga emission lines occur on the background high temperature plasma black body emission and stray light. Radial distribution of Ga in plasma in the facing plane of Ga flux is desirable

  10. Time resolved optical emission spectroscopy of cross-beam pulsed laser ablation on graphite targets

    International Nuclear Information System (INIS)

    Sangines, R.; Sanchez Ake, C.; Sobral, H.; Villagran-Muniz, M.

    2007-01-01

    Cross-beam pulsed laser ablation with two delayed lasers is performed on two perpendicular graphite targets. The time delay between lasers is varied by up to 5 μs, and physical changes on the second plasma, due to the interaction with the first generated one, are determined by time resolved optical emission spectroscopy

  11. A rapid screening method for heavy metals in biological materials by emission spectroscopy.

    Science.gov (United States)

    Blacklock, E C; Sadler, P A

    1981-06-02

    A semi-quantitative screening method for heavy metals in biological material is described. The metals are complexed with ammonium pyrrolidine dithiocarbamate, sodium diethyl dithiocarbamate and potassium sodium tartrate. The solutions are adjusted to pH 4 and then extracted into chloroform. The chloroform phase is evaporated onto a matrix mixture of lithium fluoride and graphite. The sample is analysed by direct current arc emission spectroscopy using a 3 metre grating spectrograph. The spectra are recorded on a photographic plate. The method is developed on aqueous and spiked samples and then applied to in vivo samples containing toxic levels of heavy metals. Atomic absorption spectroscopy is used to check standard concentrations and to monitor the efficiency of the extraction procedure.

  12. Comparison endpoint study of process plasma and secondary electron beam exciter optical emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stephan Thamban, P. L.; Yun, Stuart; Padron-Wells, Gabriel; Hosch, Jimmy W.; Goeckner, Matthew J. [Department of Mechanical Engineering, University of Texas at Dallas, 800W Campbell Road, Richardson, Texas 75080 (United States); Department of Electrical Engineering, University of Texas at Dallas, 800W Campbell Road, Richardson, Texas 75080 (United States); Verity Instruments, Inc., 2901 Eisenhower Street, Carrollton, Texas 75007 (United States); Department of Mathematical Sciences, University of Texas at Dallas, 800 W Campbell Road, Richardson, Texas 75080 (United States)

    2012-11-15

    Traditionally process plasmas are often studied and monitored by optical emission spectroscopy. Here, the authors compare experimental measurements from a secondary electron beam excitation and direct process plasma excitation to discuss and illustrate its distinctiveness in the study of process plasmas. They present results that show excitations of etch process effluents in a SF{sub 6} discharge and endpoint detection capabilities in dark plasma process conditions. In SF{sub 6} discharges, a band around 300 nm, not visible in process emission, is observed and it can serve as a good indicator of etch product emission during polysilicon etches. Based on prior work reported in literature the authors believe this band is due to SiF{sub 4} gas phase species.

  13. Evaluation of skeletal muscle during calf exercise by 31-phosphorus magnetic resonance spectroscopy in patients on statin medications.

    Science.gov (United States)

    Wu, Jim S; Buettner, Catherine; Smithline, Howard; Ngo, Long H; Greenman, Robert L

    2011-01-01

    Muscle pain is a common side effect of statin medications, but the cause is poorly understood. We characterized phosphocreatine (PCr) exercise recovery kinetics in 10 patients with hypercholesterolemia before and after a 4-week regimen of statin therapy using 31-phosphorus magnetic resonance spectroscopy ((31) P-MRS). (31) P spectra were obtained before, during, and after exercise on a calf flexion pedal ergometer. Creatine kinase (CK) serum levels were drawn before and after statin therapy. The mean metabolic recovery time constant in subjects increased from 28.1 s (SE = 6.5 s) to 55.4 s (SE = 7.4 s) after statin therapy. The unweighted mean of the pre/post-recovery time difference was -27.3 s (SE = 12.4 s; P = 0.02). Pre- and post-therapy CK levels were not significantly different (P = 0.50). Metabolic recovery time in the calf is prolonged in patients after statin use. This suggests that statins impair mitochondrial oxidative function, and (31) P MRS is a potential study model for statin-associated myopathy. Copyright © 2010 Wiley Periodicals, Inc.

  14. Determination of Metals Present in Textile Dyes Using Laser-Induced Breakdown Spectroscopy and Cross-Validation Using Inductively Coupled Plasma/Atomic Emission Spectroscopy

    Directory of Open Access Journals (Sweden)

    K. Rehan

    2017-01-01

    Full Text Available Laser-induced breakdown spectroscopy (LIBS was used for the quantitative analysis of elements present in textile dyes at ambient pressure via the fundamental mode (1064 nm of a Nd:YAG pulsed laser. Three samples were collected for this purpose. Spectra of textile dyes were acquired using an HR spectrometer (LIBS2000+, Ocean Optics, Inc. having an optical resolution of 0.06 nm in the spectral range of 200 to 720 nm. Toxic metals like Cr, Cu, Fe, Ni, and Zn along with other elements like Al, Mg, Ca, and Na were revealed to exist in the samples. The %-age concentrations of the detected elements were measured by means of standard calibration curve method, intensities of every emission from every species, and calibration-free (CF LIBS approach. Only Sample 3 was found to contain heavy metals like Cr, Cu, and Ni above the prescribed limit. The results using LIBS were found to be in good agreement when compared to outcomes of inductively coupled plasma/atomic emission spectroscopy (ICP/AES.

  15. Time-resolved measurement of emission profiles in pulsed radiofrequency glow discharge optical emission spectroscopy: Investigation of the pre-peak

    International Nuclear Information System (INIS)

    Alberts, D.; Horvath, P.; Nelis, Th.; Pereiro, R.; Bordel, N.; Michler, J.; Sanz-Medel, A.

    2010-01-01

    Radiofrequency glow discharge coupled to optical emission spectroscopy has been used in pulsed mode in order to perform a detailed study of the measured temporal emission profiles for a wide range of copper transitions. Special attention has been paid to the early emission peak (or so-called pre-peak), observed at the beginning of the emission pulse profile. The effects of the important pulse parameters such as frequency, duty cycle, pulse width and power-off time, have been studied upon the Cu pulse emission profiles. The influence of discharge parameters, such as pressure and power, was studied as well. Results have shown that the intensity observed in the pre-peak can be 10 times as large as the plateau value for resonant lines and up to 5 times in case of transitions to the metastable levels. Increasing pressure or power increased the pre-peak intensity while its appearance in time changed. The pre-peak decreased when the discharge off-time was shorter than 100 μs. According to such results, the presence of the pre-peak could be probably due to the lack of self-absorption during the first 50 μs, and not to the ignition of the plasma. Under the selected operation conditions, the use of the pre-peak emission as analytical signals increases the linearity of calibration curves for resonant lines subjected to self-absorption at high concentrations.

  16. Time-resolved measurement of emission profiles in pulsed radiofrequency glow discharge optical emission spectroscopy: Investigation of the pre-peak

    Energy Technology Data Exchange (ETDEWEB)

    Alberts, D. [Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, Julian Claveria 8, 33006 Oviedo (Spain); Horvath, P. [Swiss Federal Laboratories for Materials Testing and Research (EMPA), Feuerwerkerstrasse 39, 3602 Thun (Switzerland); Nelis, Th. [LAPLACE, Universite Paul Sabatier, 118 rte de Narbonne, Bat3R2, 31062 Toulouse Cedex (France); CU Jean Francois Champollion, Place de Verdun 81012 Albi Cedex 9 (France); Pereiro, R. [Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, Julian Claveria 8, 33006 Oviedo (Spain); Bordel, N. [Department of Physics, Faculty of Science, University of Oviedo, Calvo Sotelo, 33007 Oviedo (Spain); Michler, J. [Swiss Federal Laboratories for Materials Testing and Research (EMPA), Feuerwerkerstrasse 39, 3602 Thun (Switzerland); Sanz-Medel, A., E-mail: asm@uniovi.e [Department of Physical and Analytical Chemistry, Faculty of Chemistry, University of Oviedo, Julian Claveria 8, 33006 Oviedo (Spain)

    2010-07-15

    Radiofrequency glow discharge coupled to optical emission spectroscopy has been used in pulsed mode in order to perform a detailed study of the measured temporal emission profiles for a wide range of copper transitions. Special attention has been paid to the early emission peak (or so-called pre-peak), observed at the beginning of the emission pulse profile. The effects of the important pulse parameters such as frequency, duty cycle, pulse width and power-off time, have been studied upon the Cu pulse emission profiles. The influence of discharge parameters, such as pressure and power, was studied as well. Results have shown that the intensity observed in the pre-peak can be 10 times as large as the plateau value for resonant lines and up to 5 times in case of transitions to the metastable levels. Increasing pressure or power increased the pre-peak intensity while its appearance in time changed. The pre-peak decreased when the discharge off-time was shorter than 100 {mu}s. According to such results, the presence of the pre-peak could be probably due to the lack of self-absorption during the first 50 {mu}s, and not to the ignition of the plasma. Under the selected operation conditions, the use of the pre-peak emission as analytical signals increases the linearity of calibration curves for resonant lines subjected to self-absorption at high concentrations.

  17. Non-invasive quantitation of phosphorus metabolites in human brain and brain tumors by magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Naruse, Shoji; Higuchi, Toshihiro; Horikawa, Yoshiharu; Tanaka, Chuzo; Roth, K.; Hubesch, B.; Meyerhoff, D.J.; Weiner, M.W.

    1989-01-01

    In obtaining localized magnetic resonance spectra in the clinical setting, the exact determination of volume of interest (VOI), the relative sensitivity of detection within the VOI, the inhomogeneity of B 1 field, the Q factor of the coil, and saturation factors should be considered. Taking these items into account, a quantitative method for calculating the absolute amount of phosphorus metabolites was developed. Using this method, phosphorus metabolites in the brain were determined in 15 patients with brain tumors - meningioma (8) and astrocytoma (7), and 10 normal volunteers. The integrals for metabolite signals were determined by using the curve-fitting software. The concentrations for ATP, PCr, PDE, inorganic orthophosphate (Pi), and phosphomonosters (PME) were 2.5, 4.9, 11.3, 1.9 and 3.9 mM, respectively, in the normal brain. For the brain tumors, phosphorus metabolites were decreased, except for Pi and PME. These results encourage the clinical use of this method in the quantitative analysis of metabolites of the diseased brain. (Namekawa, K)

  18. Single photon infrared emission spectroscopy: a study of IR emission from UV laser excited PAHs between 3 and 15 micrometers

    Science.gov (United States)

    Cook, D. J.; Schlemmer, S.; Balucani, N.; Wagner, D. R.; Harrison, J. A.; Steiner, B.; Saykally, R. J.

    1998-01-01

    Single-photon infrared emission spectroscopy (SPIRES) has been used to measure emission spectra from polycyclic aromatic hydrocarbons (PAHs). A supersonic free-jet expansion has been used to provide emission spectra of rotationally cold and vibrationally excited naphthalene and benzene. Under these conditions, the observed width of the 3.3-micrometers (C-H stretch) band resembles the bandwidths observed in experiments in which emission is observed from naphthalene with higher rotational energy. To obtain complete coverage of IR wavelengths relevant to the unidentified infrared bands (UIRs), UV laser-induced desorption was used to generate gas-phase highly excited PAHs. Lorentzian band shapes were convoluted with the monochromator-slit function in order to determine the widths of PAH emission bands under astrophysically relevant conditions. Bandwidths were also extracted from bands consisting of multiple normal modes blended together. These parameters are grouped according to the functional groups mostly involved in the vibration, and mean bandwidths are obtained. These bandwidths are larger than the widths of the corresponding UIR bands. However, when the comparison is limited to the largest PAHs studied, the bandwidths are slightly smaller than the corresponding UIR bands. These parameters can be used to model emission spectra from PAH cations and cations of larger PAHs, which are better candidate carriers of the UIRs.

  19. Characterization of cover crops by NMR spectroscopy: impacts on soil carbon, nitrogen and phosphorus under tillage regimes

    Directory of Open Access Journals (Sweden)

    Arminda Moreira de Carvalho

    Full Text Available The objective of this study was to investigate the chemical composition of cover crops by solid-state CPMAS 13C NMR spectroscopy and its effects on carbon, nitrogen and phosphorus in a Typic Acrustox. Cover crops (Crotalaria juncea, Canavalia brasiliensis, Cajanus cajan, Mucuna pruriens and Raphanus sativus and natural fallow were studied in rotation with maize under conventional and no-tillage regimes. Tissues of Crotalaria juncea, Canavalia brasiliensis, Mucuna pruriens and Raphanus sativus were analyzed using CPMAS 13C NMR spectroscopy. Soil samples were collected at the end of the growing season of the cover crops (September 2002 and during the grain filling period in corn from 0-5 and 5-10 cm layers. Cajanus cajan presented the lowest content of polysaccharides and along with Mucuna pruriens presented the highest percentage of aromatic carbon compounds, reflecting the slow decomposition of highly lignified material. Carbon stocks were higher in the superficial soil layer and under no-tillage due to the accumulation and slower decomposition of plant tissues under these conditions. Increases in the C/N ratio of the soil with Mucuna pruriens and the C/P ratio with Cajanus cajan in the dry season were also related to slower rates of decomposition, caused by the large concentration of aromatic compounds in the tissues of these species. The higher C/P ratios found at 0-5 cm layer are due to higher values of P (Mehlich-1 at 5-10 cm (25 mg kg-1 layer and the higher concentration of carbon in the superficial soil layer as a result of the accumulation of plant residues.

  20. Determination of heavy metals in solid emission and immission samples using atomic absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Fara, M.; Novak, F. [EGU Prague, PLC, Bichovice, Prague (Czechoslovakia)

    1995-12-01

    Both flame and electrothermal methods of atomic absorption spectroscopy (AAS) have been applied to the determination of Al, As, Be, Ca, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, TI, Se, V and Zn in emission and emission (deposition) samples decomposed in open PTFE test-tubes by individual fuming-off hydrofluoric, perchloroic and nitric acid. An alternative hydride technique was also used for As and Se determination and Hg was determined using a self-contained AAS analyzer. A graphite platform proved good to overcome non-spectral interferences in AAS-ETA. Methods developed were verified by reference materials (inc. NBS 1633a).

  1. Analysis of two colliding laser-produced plasmas by emission spectroscopy and fast photography

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Ake, C., E-mail: citlali.sanchez@ccadet.unam.m [Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-186, Mexico D.F., C.P. 04510 (Mexico); Mustri-Trejo, D. [Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-186, Mexico D.F., C.P. 04510 (Mexico); Garcia-Fernandez, T. [Universidad Autonoma de la Ciudad de Mexico, Prolongacion San Isidro 151, Col. San Lorenzo Tezonco, Mexico DF, C.P. 09790 (Mexico); Villagran-Muniz, M. [Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-186, Mexico D.F., C.P. 04510 (Mexico)

    2010-05-15

    In this work two colliding laser-induced plasmas (LIP) on Cu and C were studied by means of time resolved emission spectroscopy and fast photography. The experiments were performed using two opposing parallel targets of Cu and C in vacuum, ablated with two synchronized ns lasers. The results showed an increased emission intensity from copper ions Cu II (368.65, 490.97, 493.16, 495.37 and 630.10 nm) and Cu III (374.47 and 379.08 nm) due to the ionization that occurs during collisions of Cu and C species. It was found that the optimum delay between pulses, which yields the maximum emission enhancement of Cu ions, depends on the sampling distance. On the other hand, the emission intensity of C lines, C II (426.70 nm), C III (406.99 and 464.74 nm) and C IV (465.83 nm), decreased and the formation of C{sub 2} molecules was observed. A comparison between the temporal evolution of the individual plasmas and their collision performed by combining imaging and the time resolved emission diagnostics, revealed an increase of the electron temperature and electron density and the splitting of the plume into slow and fast components.

  2. Soil humic-like organic compounds in prescribed fire emissions using nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Chalbot, M.-C.; Nikolich, G.; Etyemezian, V.; Dubois, D.W.; King, J.; Shafer, D.; Gamboa da Costa, G.; Hinton, J.F.; Kavouras, I.G.

    2013-01-01

    Here we present the chemical characterization of the water-soluble organic carbon fraction of atmospheric aerosol collected during a prescribed fire burn in relation to soil organic matter and biomass combustion. Using nuclear magnetic resonance spectroscopy, we observed that humic-like substances in fire emissions have been associated with soil organic matter rather than biomass. Using a chemical mass balance model, we estimated that soil organic matter may contribute up to 41% of organic hydrogen and up to 27% of water-soluble organic carbon in fire emissions. Dust particles, when mixed with fresh combustion emissions, substantially enhances the atmospheric oxidative capacity, particle formation and microphysical properties of clouds influencing the climatic responses of atmospheric aeroso. Owing to the large emissions of combustion aerosol during fires, the release of dust particles from soil surfaces that are subjected to intense heating and shear stress has, so far, been lacking. -- Highlights: •We characterized the water-soluble organic carbon (WSOC) of fire emissions by NMR. •Distinct patterns were observed for soil dust and vegetation combustion emissions. •Soil organic matter accounted for most of WSOC in early prescribed burn emissions. -- Humic-like soil organic matter may be an important component of particulate emissions in the early stages of wildfires

  3. Substoichiometric extraction of phosphorus

    International Nuclear Information System (INIS)

    Shigematsu, T.; Kudo, K.

    1981-01-01

    A study of the substoichiometric extraction of phosphorus is described. Phosphorus was extracted in the form of ternary compounds such as ammonium phosphomolybdate, 8-hydroxyquinolinium phosphomolybdate, tetraphenylarsonium phosphomolybdate and tri-n-octylamine phosphomolybdate. Consequently, phosphorus was extracted substoichiometrically by the addition of a substoichiometric amount of molybdenum for the four phosphomolybdate compounds. On the other hand, phosphorus could be separated substoichiometrically with a substoichiometric amount of tetraphenylarsonium chloride or tri-n-octylamine. Stoichiometric ratios of these ternary compounds obtained substoichiometrically were 1:12:3 for phosphorus, molybdenum and organic reagent. The applicability of these compounds to phosphorus determination is also discussed. (author)

  4. Trichlorosilane and silicon tetrachloride sample preparation for determination of boron, phosphorus and arsenic microelements

    International Nuclear Information System (INIS)

    Stolyarova, I.V.; Orlova, V.A.

    1995-01-01

    The conditions of sample preparation ensuring virtually complete elimination of boron, phosphorus, and arsenic losses are elaborated. Analysis procedures are proposed that involve hydrolysis in an autoclave for exothermic reactions and/or in an open reaction reservoir on frozen twice-distilled water with complexing-agent and oxidant solutionsd applied layer-by-layer, with the possible subsequent atomic-emission, extraction-spectrophotometric, or extraction-colorimetric determination of boron, phosphorus, and arsenic. The procedures improve the accuracy and precision of the results and reduce the duration of chemical preparation due to the quantitative preconcentration of boron, phosphorus, and arsenic; they almost completely eliminate the possibility of the formation of volatile fluoride forms of these elements. 11 refs.; 3 tabs

  5. Minimum TE gradient-recalled phosphorus imaging sequence on a whole-body imager

    International Nuclear Information System (INIS)

    Listerud, J.; Lenkinski, R.E.; Axel, L.

    1989-01-01

    To define the lower limits of spatial resolution in gradient-recalled echo phosphorus studies at 1.5 T, the authors have implemented a phosphorus gradient-recalled imaging sequence on the Signa imager. All gradient ramps for the section-selective rephasing lobe, the phase-encoding pulse, and the dephasing pulse of the frequency-encoding gradient are slowed at the maximal rate. Consequently, with a field of view of 24 cm, an in-plane resolution of 3 cm, an echo appropriately offset, an RF bandwidth of 1.2 KHz, and a section thickness of 5 cm, the echo time may be reduced to 1.35 msec. The reconstruction algorithm has been modified to support oversampled data of low spatial resolution appropriate for phosphorus imaging. The sequence will acquire H-1 images and supports the automatic and manual prescan features of the commercial instrument. To facilitate setup in the phosphorus imaging mode the sequence supports the product spectroscopic mode with a DRESS (depth recalled surface coil spectroscopy) sequence and a section profile sequence for appropriate shimming, receiver characteristics, and averaging requirements. The suitability for adaptation of this sequence to three-dimensional chemical shift imaging is discussed

  6. X-ray absorption and X-ray emission spectroscopy theory and applications

    CERN Document Server

    Lamberti, Carlo

    2016-01-01

    During the last two decades, remarkable and often spectacular progress has been made in the methodological and instrumental aspects of x–ray absorption and emission spectroscopy. This progress includes considerable technological improvements in the design and production of detectors especially with the development and expansion of large-scale synchrotron reactors All this has resulted in improved analytical performance and new applications, as well as in the perspective of a dramatic enhancement in the potential of x–ray based analysis techniques for the near future. This comprehensive two-volume treatise features articles that explain the phenomena and describe examples of X–ray absorption and emission applications in several fields, including chemistry, biochemistry, catalysis, amorphous and liquid systems, synchrotron radiation, and surface phenomena. Contributors explain the underlying theory, how to set up X–ray absorption experiments, and how to analyze the details of the resulting spectra. X-R...

  7. Use of Phosphorus Isotopes for Improving Phosphorus Management in Agricultural Systems

    International Nuclear Information System (INIS)

    2016-10-01

    Phosphorus is an essential element in plant, human and animal nutrition. Soils with low levels of phosphorus are widespread in many regions of the world, and the deficiency limits plant growth and reduces crop production and food quality. This publication provides comprehensive and up to date information on several topics related to phosphorus in soil–plant systems, in agricultural systems and in the environment. It presents the theoretical background as well as practical information on how to use nuclear and radioisotope tracer techniques in both laboratory and greenhouse experiments to assess soil phosphorus forms and plant-available soil phosphorus pools, and to understand the cycling processes in soil–plant systems. The publication focuses on practical applications of radiotracer techniques and can serve as resource material for research projects on improving sustainable phosphorus management in agricultural systems and as practical guidance on the use of phosphate isotopes in soil–plant research

  8. Light emitting diode excitation emission matrix fluorescence spectroscopy.

    Science.gov (United States)

    Hart, Sean J; JiJi, Renée D

    2002-12-01

    An excitation emission matrix (EEM) fluorescence instrument has been developed using a linear array of light emitting diodes (LED). The wavelengths covered extend from the upper UV through the visible spectrum: 370-640 nm. Using an LED array to excite fluorescence emission at multiple excitation wavelengths is a low-cost alternative to an expensive high power lamp and imaging spectrograph. The LED-EEM system is a departure from other EEM spectroscopy systems in that LEDs often have broad excitation ranges which may overlap with neighboring channels. The LED array can be considered a hybrid between a spectroscopic and sensor system, as the broad LED excitation range produces a partially selective optical measurement. The instrument has been tested and characterized using fluorescent dyes: limits of detection (LOD) for 9,10-bis(phenylethynyl)-anthracene and rhodamine B were in the mid parts-per-trillion range; detection limits for the other compounds were in the low parts-per-billion range (LED-EEMs were analyzed using parallel factor analysis (PARAFAC), which allowed the mathematical resolution of the individual contributions of the mono- and dianion fluorescein tautomers a priori. Correct identification and quantitation of six fluorescent dyes in two to six component mixtures (concentrations between 12.5 and 500 ppb) has been achieved with root mean squared errors of prediction (RMSEP) of less than 4.0 ppb for all components.

  9. Determination of rare earth elements in aluminum by inductively coupled plasma-atomic emission spectroscopy

    International Nuclear Information System (INIS)

    Mahanti, H.S.; Barnes, R.M.

    1983-01-01

    Inductively coupled plasma-atomic emission spectroscopy is evaluated for the determination of 14 rare earth elements in aluminum. Spectral line interference, limit of detection, and background equivalent concentration values are evaluated, and quantitative recovery is obtained from aluminum samples spiked with rare earth elements. The procedure is simple and suitable for routine process control analysis. 20 references, 5 tables

  10. Optical emission spectroscopy during fabrication of indium-tin-oxynitride films by RF-sputtering

    International Nuclear Information System (INIS)

    Koufaki, M.; Sifakis, M.; Iliopoulos, E.; Pelekanos, N.; Modreanu, M.; Cimalla, V.; Ecke, G.; Aperathitis, E.

    2006-01-01

    Indium-tin-oxide (ITO) and indium-tin-oxynitride (ITON) films have been deposited on glass by rf-sputtering from an ITO target, using Ar plasma and N 2 plasma, respectively, and different rf-power. Optical emission spectroscopy (OES) was employed to identify the species present in the plasma and to correlate them with the properties of the ITO and ITON thin films. Emission lines of ionic In could only be detected in N 2 plasma, whereas in the Ar plasma additional lines corresponding to atomic In and InO, were detected. The deposition rate of thin films was correlated with the In species, rather than the nitrogen species, emission intensity in the plasma. The higher resistivity and lower carrier concentration of the ITON films, as compared to the respective properties of the ITO films, were attributed to the incorporation of nitrogen, instead of oxygen, in the ITON structure

  11. New chiral zwitterionic phosphorus heterocycles: synthesis, structure, properties and application as chiral solvating agents.

    Science.gov (United States)

    Sheshenev, Andrey E; Boltukhina, Ekaterina V; Grishina, Anastasiya A; Cisařova, Ivana; Lyapkalo, Ilya M; Hii, King Kuok Mimi

    2013-06-17

    A family of new chiral zwitterionic phosphorus-containing heterocycles (zPHC) have been derived from methylene-bridged bis(imidazolines). These structures were unambiguously determined, including single-crystal XRD analysis for two compounds. The stability, acid/base and electronic properties of these dipolar phosphorus heterocycles were subsequently investigated. zPHCs can be successfully employed as a new class of chiral solvating agents for the enantiodifferentiation of chiral carboxylic and sulfonic acids by NMR spectroscopy. The stoichiometry and binding constants for the donor-acceptor complexes formed were established by NMR titration methods. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. 'Beam-emission spectroscopy' diagnostics also measure edge fast-ion light

    International Nuclear Information System (INIS)

    Heidbrink, W W; Bortolon, A; McKee, G R; Smith, D R

    2011-01-01

    Beam-emission spectroscopy (BES) diagnostics normally detect fluctuations in the light emitted by an injected neutral beam. Under some circumstances, however, light from fast ions that charge exchange in the high neutral-density region at the edge of the plasma make appreciable contributions to the BES signals. This 'passive' fast-ion D α (FIDA) light appears in BES signals from both the DIII-D tokamak and the National Spherical Torus Experiment (NSTX). One type of passive FIDA light is associated with classical orbits that traverse the edge. Another type is caused by instabilities that expel fast ions from the core; this light can complicate measurement of the instability eigenfunction.

  13. Analysis of bauxite by inductively coupled plasma-atomic emission spectroscopy

    Science.gov (United States)

    Barnes, Ramon M.; Mahanti, Himansu S.

    Methods are described for the analysis of bauxite by inductively coupled plasma (ICP) emission spectroscopy. Bauxite samples were dissolved either in HCl, HNO 3, and HF at 160°C in all-PTFE bomb or fused with NaOH. Spectral lines were selected after examination of experimental wavelength scans at each potential analyte wavelength. Limits of detection, background equivalent concentration, and analytical figures of merit were established. The accuracy of the method was confirmed by determining 17 elements in NBS-SRM bauxite samples. Silicon in HF solutions was analyzed using a modified ICP torch with a graphite injector tube, an inert nebulizer using PTFE capillary tubes, and a PTFE spray chamber.

  14. Study of optical emission spectroscopy with inductively coupled plasma torch

    International Nuclear Information System (INIS)

    Bauer, M.

    1982-01-01

    Inductively coupled plasma optical emission spectroscopy is an excellent tool for quantitative multielement trace analysis. This paper describes the performance of a computer-controlled sequential measurement system. Chemical and ionization interferences are shown to be negligible due to the characteristics of the inductively coupled plasma, spectral interferences are eliminated by using a high-resolution monochromator and computer data handling. Good accuracy is achieved for most of the interesting elements, as is shown from both an interlaboratory test and from comparison of the results of water samples from the rivers Elbe and Weser with those achieved with neutron activation and X-ray fluorescence analysis. (orig.) [de

  15. Preparation, flame retardancy and thermal behavior of a novel UV-curable coating containing phosphorus and nitrogen

    Energy Technology Data Exchange (ETDEWEB)

    Xing Weiyi [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China); Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren' ai Road, Suzhou, Jiangsu 215123 (China); Song Lei [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China); Lv Pin; Jie Ganxin [State Key Laboratory of Environmental Adaptability for Industrial Products, China National Electric Apparatus Research Institute, Guangzhou 510300 (China); Wang Xin; Lv Xiaoqi [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China); Hu Yuan, E-mail: yuanhu@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzai Road, Hefei, Anhui 230026 (China); Suzhou Institute for Advanced Study, University of Science and Technology of China, 166 Ren' ai Road, Suzhou, Jiangsu 215123 (China)

    2010-10-01

    A novel phosphorus monomer, 2,2-dimethyl-1,3-propanediol acryloyloxyethyl phosphate (DPHA), has been synthesized through phosphorus oxychloride reacting with neopentyl glycol and 2-hydroxyethyl acrylate (HEA). Its structure was characterized by Fourier transform infrared spectroscopy (FTIR), {sup 1}H nuclear magnetic resonance spectroscopy ({sup 1}H NMR) and {sup 31}P nuclear magnetic resonance spectroscopy ({sup 31}P NMR). A series of UV-curable resins were manufactured by blending DPHA with triglycidyl isocyanurate acrylate (TGICA) at different weight ratio. The fire performance was examined by Microscale Combustion Calorimetry (MCC). The results obtained from MCC indicated that the addition of DPHA to TGICA decreased the peak heat release rate (PHRR), heat release capacity (HRC) and total heat of combustion (THC). The char residues of the composites were observed by scanning electron microscopy (SEM). The thermal decomposition behavior of DPHA/TGICA composites was characterized by using thermogravimetric analysis/infrared spectrometry (TGA-IR). The test results indicated that when the weight ratio of DPHA: TGICA = 1/1, the onset temperature of the composite was highest and the largest char residue at 700 deg. C was observed. The change of chemical structure during the thermal degradation process was monitored by real-time FTIR analysis. TGA-IR results indicated that the evolved products were CO, CO{sub 2}, water, NH{sub 3}, carbonyl, phosphorus oxides and aromatic compounds according to the temperature of onset formation.

  16. phosphorus sorption capacity as a guide for phosphorus availability

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    drained, light yellowish brown, loamy sand ... Dongola 2 Akked series: Deep, dark grayish brown, clay ... energy. Statistical analysis. Data collected were statistically analysed using ANOVA of MStatc ... phosphorus sorbed versus phosphorus.

  17. Study of atomic and molecular emission spectra of Sr by laser induced breakdown spectroscopy (LIBS).

    Science.gov (United States)

    Bhatt, Chet R; Alfarraj, Bader; Ayyalasomayajula, Krishna K; Ghany, Charles; Yueh, Fang Y; Singh, Jagdish P

    2015-12-01

    Laser Induced Breakdown Spectroscopy (LIBS) is an ideal analytical technique for in situ analysis of elemental composition. We have performed a comparative study of the quantitative and qualitative analysis of atomic and molecular emission from LIBS spectra. In our experiments, a mixture of SrCl2 and Al2O3 in powder form was used as a sample. The atomic emission from Sr and molecular emission from SrCl and SrO observed in LIBS spectra were analyzed. The optimum laser energies, gate delays, and gate widths for selected atomic lines and molecular bands were determined from spectra recorded at various experimental parameters. These optimum experimental conditions were used to collect calibration data, and the calibration curves were used to predict the Sr concentration. Limits of detection (LODs) for selected atomic and molecular emission spectra were determined.

  18. Diagnosis of the local thermal equilibrium by optical emission spectroscopy in the evolution of electric discharge

    International Nuclear Information System (INIS)

    Valdivia B, R.; Pacheco S, J.; Pacheco P, M.; Ramos F, F.; Cruz A, A.; Velazquez P, S.

    2008-01-01

    In this work applies the technique of optical emission spectroscopy to diagnose the temperature of the species generated in plasma in the transition to glow discharge arc. Whit this diagnosis is possible to determine the local thermal equilibrium conditions of the discharge. (Author)

  19. Bayesian modelling of the emission spectrum of the Joint European Torus Lithium Beam Emission Spectroscopy system.

    Science.gov (United States)

    Kwak, Sehyun; Svensson, J; Brix, M; Ghim, Y-C

    2016-02-01

    A Bayesian model of the emission spectrum of the JET lithium beam has been developed to infer the intensity of the Li I (2p-2s) line radiation and associated uncertainties. The detected spectrum for each channel of the lithium beam emission spectroscopy system is here modelled by a single Li line modified by an instrumental function, Bremsstrahlung background, instrumental offset, and interference filter curve. Both the instrumental function and the interference filter curve are modelled with non-parametric Gaussian processes. All free parameters of the model, the intensities of the Li line, Bremsstrahlung background, and instrumental offset, are inferred using Bayesian probability theory with a Gaussian likelihood for photon statistics and electronic background noise. The prior distributions of the free parameters are chosen as Gaussians. Given these assumptions, the intensity of the Li line and corresponding uncertainties are analytically available using a Bayesian linear inversion technique. The proposed approach makes it possible to extract the intensity of Li line without doing a separate background subtraction through modulation of the Li beam.

  20. Changes in phosphorus magnetic resonance spectra during the cell cycle of phosphorus limited phased culture of Candida utilis

    International Nuclear Information System (INIS)

    Dawson, P.S.S.; MacDonald, J.C.

    1987-01-01

    Cell extracts, serially obtained from Candida utilis grown in continuous (synchrony) culture under phosphate limitation during an 8-h cycle and examined by NMR spectroscopy, revealed changes in polyphosphate content during the cycle period: other phosphorus containing components showed relatively little change. Initially zero, the polyphosphate content increased rapidly to a maximum after 30 min that coincided with exhaustion of phosphate from the culture, and then decreased slowly back to zero at the end of the cycle. The results suggest that polyphosphate, usually considered to function as a reserve material, actively participates during the cell cycle. 12 refs.; 1 figure; 1 table

  1. New Chiral Zwitterionic Phosphorus Heterocycles: Synthesis, Structure, Properties and Application as Chiral Solvating Agents

    Czech Academy of Sciences Publication Activity Database

    Sheshenev, A. E.; Boltukhina, E. V.; Grishina, Anastasia; Císařová, I.; Lyapkalo, Ilya; Hii, K. K.

    2013-01-01

    Roč. 19, č. 25 (2013), s. 8136-8143 ISSN 0947-6539 Grant - others:7th European Community Framework Programme(XE) FP7-252247 Institutional support: RVO:61388963 Keywords : binding constants * chirality * enantioselectivity * NMR spectroscopy * phosphorus heterocycles * zwitterions Subject RIV: CC - Organic Chemistry Impact factor: 5.696, year: 2013

  2. Raman spectra of terbium trichloride, phosphorus pentachloride and their molten mixtures

    International Nuclear Information System (INIS)

    Salyulev, A.B.; Zakir'yanova, I.D.

    2008-01-01

    Raman spectroscopy was used to study in situ the behavior of individual terbium trichloride and phosphorus pentachloride in different aggregative states as a function of temperature, and of solutions of PCl 5 vapors in molten TbCl 3 . A conclusion is drawn about their structure and the nature of phase transformations and chemical reactions in wide ranges of temperature and saturated vapor pressures [ru

  3. p-type ZnO films with solid-source phosphorus doping by molecular-beam epitaxy

    International Nuclear Information System (INIS)

    Xiu, F.X.; Yang, Z.; Mandalapu, L.J.; Liu, J.L.; Beyermann, W. P.

    2006-01-01

    Phosphorus-doped p-type ZnO films were grown on r-plane sapphire substrates using molecular-beam epitaxy with a solid-source GaP effusion cell. X-ray diffraction spectra and reflection high-energy electron diffraction patterns indicate that high-quality single crystalline (1120) ZnO films were obtained. Hall and resistivity measurements show that the phosphorus-doped ZnO films have high hole concentrations and low resistivities at room temperature. Photoluminescence (PL) measurements at 8 K reveal a dominant acceptor-bound exciton emission with an energy of 3.317 eV. The acceptor energy level of the phosphorus dopant is estimated to be 0.18 eV above the valence band from PL spectra, which is also consistent with the temperature dependence of PL measurements

  4. Study of the phosphine plasma decomposition and its formation by ablation of red phosphorus in hydrogen plasma

    Science.gov (United States)

    Bruno, G.; Losurdo, M.; Capezzuto, P.

    1995-03-01

    Mass spectrometry and optical emission spectroscopy have been used to study the chemistry of PH(sub 3) plasma decomposition as well as its formation by ablation of red phosphorus in hydrogen plasma. It has been shown that PH(sub 3) decomposition easily equilibrates at low levels of PH(sub 3) depletion (15%-30%), this depending mainly on the rf power. The ablation of red phosphorus in H(sub 2) plasma produces phosphine in significant amount, depending mainly on the total pressure but also on the rf power. It has also been found that H(sup *) and PH(sup *) emitting species originate not only by the dissociative excitation of H(sub 2) and PH(sub 3), respectively, but also by the direct excitation of the same species in the ground state. Considerations are developed on how to derive the H-atom and PH radical densities by actinometry, under specific experimental conditions. Besides, the linear dependence of PH(sub 3) formation rate, r(sub PH(3)), on H-atom density, (left bracket) H (right bracket), leads to the definition of the kinetic equation r(sub PH(3)) = k (left bracket) H (right bracket), and to the hypothesis that the formation of PH radical on the surface or its desorption is the dominant mechanism for PH(sub 3) production.

  5. Programs in Fortran language for reporting the results of the analyses by ICP emission spectroscopy

    International Nuclear Information System (INIS)

    Roca, M.

    1985-01-01

    Three programs, written in FORTRAN IV language, for reporting the results of the analyses by ICP emission spectroscopy from data stored in files on floppy disks have been developed. They are intended, respectively, for the analyses of: 1) waters, 2) granites and slates, and 3) different kinds of geological materials. (Author) 8 refs

  6. Phosphate ore beneficiation via determination of phosphorus-to-silica ratios by Laser Induced Breakdown Spectroscopy

    International Nuclear Information System (INIS)

    Asimellis, George; Giannoudakos, Aggelos; Kompitsas, Michael

    2006-01-01

    We report development and application of an in-situ applicable method to determine phosphate ore rock quality based on Laser-Induced Breakdown Spectroscopy (LIBS). This is an economically viable method for real-time evaluation of ore phosphate rocks in order to separate high-silica pebbles prior to deep beneficiation. This is achieved by monitoring relative emission line intensities from key probe elements via single laser ablation shots: the ratio of the phosphorous to silica line intensities (P/Si ratio) provides a simple and reliable indicator of ore rock quality. This is a unique LIBS application where no other current analytical spectroscopic method (ICP or XRF) can be applied. Method development is discussed, and results with actual ore samples are presented

  7. High pressure chemistry of red phosphorus by photoactivated simple molecules

    Science.gov (United States)

    Ceppatelli, Matteo; Bini, Roberto; Fanetti, Samuele; Caporali, Maria; Peruzzini, Maurizio

    2013-06-01

    High pressure (HP) is very effective in reducing intermolecular distances and inducing unexpected chemical reactions. In particular the photoactivation of the reactants in HP conditions can lead to very efficient and selective processes. The chemistry of phosphorus is currently based on the white molecular form. The red polymeric allotrope, despite more stable and much less toxic, has not attracted much attention so far. However, switching from the white to the red form would benefit any industrial procedure, especially from an environmental point of view. On the other side, water and ethanol are renewable, environmental friendly and largely available molecules, usable as reactants and photoactivators in HP conditions. Here we report a study on the HP photoinduced reactivity of red phosphorus with water and ethanol, showing the possibility of very efficient and selective processes, leading to molecular hydrogen and valuable phosphorus compounds. The reactions have been studied by means of FTIR and Raman spectroscopy and pressure has been generated using DAC and SAC. HP reactivity has been activated by the two-photon absorption of near-UV wavelengths and occured in total absence of solvents, catalysts and radical initiators, at room T and mild pressure conditions (0.2-1.5 GPa).

  8. Shortened screening method for phosphorus fractionation in sediments A complementary approach to the standards, measurements and testing harmonised protocol

    International Nuclear Information System (INIS)

    Pardo, Patricia; Rauret, Gemma; Lopez-Sanchez, Jose Fermin

    2004-01-01

    The SMT protocol, a sediment phosphorus fractionation method harmonised and validated in the frame of the standards, measurements and testing (SMT) programme (European Commission), establishes five fractions of phosphorus according to their extractability. The determination of phosphate extracted is carried out spectrophotometrically. This protocol has been applied to 11 sediments of different origin and characteristics and the phosphorus extracted in each fraction was determined not only by UV-Vis spectrophotometry, but also by inductively coupled plasma-atomic emission spectrometry. The use of these two determination techniques allowed the differentiation between phosphorus that was present in the extracts as soluble reactive phosphorus and as total phosphorus. From the comparison of data obtained with both determination techniques a shortened screening method, for a quick evaluation of the magnitude and importance of the fractions given by the SMT protocol, is proposed and validated using two certified reference materials

  9. Characterization of phosphorus metabolism in dilated cardiomyopathy

    International Nuclear Information System (INIS)

    Auffermann, W.; Chew, W.; Tavares, N.J.; Donnelly, T.; Parmley, W.W.; Chatterjee, K.; Wolfe, C.; Higgins, C.B.

    1988-01-01

    Five patients with dilated cardiomyopathy (ejection fraction, ∼25%) and six normal volunteers were studied with localized, gated P-31 MR spectroscopy at 1.5 T. The typical peaks of adenogine triphosphate (ATP[, phosphocreatine (PCr), phosphodiesters (PD), and peaks attributable to 2,3 diphosphoglycerate, inorganic phosphate, and phosphomonoesters were identified and the areas under each peak numerically integrated after baseline correction. PCr/β-ATP was not significantly lower (1.42 +- 0.06 vs 1.54 +- 0.04), but PD/PCr (1.1 +- 0.02 vs 0.6 +- 0.1) (P ≤ .01) and PD/β-ATP (1.50 +- 0.04 vs 0.97 +- 0.17) (P ≤ .05) were significantly higher in patients with dilated cardiomyopathy compared with normal volunteers. Thus, localized, gated P-31 MR spectroscopy in cardiomyopathic patients identifies abnormal myocardial phosphorus metabolism, which might become useful to monitor noninvasively the response to positive inotropic therapy

  10. Nuclear spectroscopy with Geant4: Proton and neutron emission & radioactivity

    Science.gov (United States)

    Sarmiento, L. G.; Rudolph, D.

    2016-07-01

    With the aid of a novel combination of existing equipment - JYFLTRAP and the TASISpec decay station - it is possible to perform very clean quantum-state selective, high-resolution particle-γ decay spectroscopy. We intend to study the determination of the branching ratio of the ℓ = 9 proton emission from the Iπ = 19/2-, 3174-keV isomer in the N = Z - 1 nucleus 53Co. The study aims to initiate a series of similar experiments along the proton dripline, thereby providing unique insights into "open quantum systems". The technique has been pioneered in case studies using SHIPTRAP and TASISpec at GSI. Newly available radioactive decay modes in Geant4 simulations are going to corroborate the anticipated experimental results.

  11. FTIR Emission spectroscopy of surfaces

    Science.gov (United States)

    Van Woerkom, P. C. M.

    A number of vibrational spectroscopic techniques are available For the study of surfaces, such as ATR, IR reflection-absorption, IR emission, etc. Infrared emission is hardly used, although interesting applications are possible now due to the high sensitivity of Fourier transform IR (FTIR) spectrometers. Two examples, where infrared emission measurements are very fruitful, will be given. One is the investigation of the curing behaviour of organic coatings, the other is the in situ study of heterogeneously catalyzed reactions. Undoubtedly, infrared emission measurements offer a number of specific advantages in some cases. Especially the less critical demands on the sample preparation are important.

  12. Atom spectroscopy

    International Nuclear Information System (INIS)

    Kodling, K.

    1981-01-01

    Experiments on atom photoabsorption spectroscopy using synchrotron radiation in the 10-1000 eV range are reviewed. Properties of the necessary synchrotron radiation and the experiment on absorption spectroscopy are briefly described. Comparison with other spectroscopy methods is conducted. Some data on measuring photoabsorption, photoelectron emission and atom mass spectra are presented [ru

  13. Organic chemistry of elemental phosphorus

    International Nuclear Information System (INIS)

    Milyukov, V A; Budnikova, Yulia H; Sinyashin, Oleg G

    2005-01-01

    The principal achievements and the modern trends in the development of the chemistry of elemental phosphorus are analysed, described systematically and generalised. The possibilities and advantages of the preparation of organophosphorus compounds directly from white phosphorus are demonstrated. Attention is focused on the activation and transformation of elemental phosphorus in the coordination sphere of transition metal complexes. The mechanisms of the reactions of white phosphorus with nucleophilic and electrophilic reagents are discussed. Electrochemical approaches to the synthesis of organic phosphorus derivatives based on white phosphorus are considered.

  14. Phosphorus removal from aqueous solution in parent and aluminum-modified eggshells: thermodynamics and kinetics, adsorption mechanism, and diffusion process.

    Science.gov (United States)

    Guo, Ziyan; Li, Jiuhai; Guo, Zhaobing; Guo, Qingjun; Zhu, Bin

    2017-06-01

    Parent and aluminum-modified eggshells were prepared and characterized with X-ray diffraction, specific surface area measurements, infrared spectroscopy, zeta potential, and scanning electron microscope, respectively. Besides, phosphorus adsorptions in these two eggshells at different temperatures and solution pH were carried out to study adsorption thermodynamics and kinetics as well as the mechanisms of phosphorus adsorption and diffusion. The results indicated that high temperature was favorable for phosphorus adsorption in parent and aluminum-modified eggshells. Alkaline solution prompted phosphorus adsorption in parent eggshell, while the maximum adsorption amount was achievable at pH 4 in aluminum-modified eggshell. Adsorption isotherms of phosphorus in these eggshells could be well described by Langmuir and Freundlich models. Phosphorus adsorption amounts in aluminum-modified eggshell were markedly higher compared to those in parent eggshell. Adsorption heat indicated that phosphorus adsorption in parent eggshell was a typically physical adsorption process, while chemical adsorption mechanism of ion exchange between phosphorus and hydroxyl groups on the surface of eggshells was dominated in aluminum-modified eggshell. The time-resolved uptake curves showed phosphorus adsorption in aluminum-modified eggshell was significantly faster than that in parent eggshell. Moreover, there existed two clear steps in time-resolved uptake curves of phosphorus in parent eggshell. Based on pseudo-second order kinetic model and intraparticle diffusion model, we inferred more than one process affected phosphorus adsorption. The first process was the diffusion of phosphorus through water to external surface and the opening of pore channel in the eggshells, and the second process was mainly related to intraparticle diffusion.

  15. Wide electrochemical window of supercapacitors from coffee bean-derived phosphorus-rich carbons.

    Science.gov (United States)

    Huang, Congcong; Sun, Ting; Hulicova-Jurcakova, Denisa

    2013-12-01

    Phosphorus-rich carbons (PCs) were prepared by phosphoric acid activation of waste coffee grounds in different impregnation ratios. PCs were characterized by nitrogen and carbon dioxide adsorption and X-ray photoelectron spectroscopy. The results indicate that the activation step not only creates a porous structure, but also introduces various phosphorus and oxygen functional groups to the surface of carbons. As evidenced by cyclic voltammetry, galvanostatic charge/discharge, and wide potential window tests, a supercapacitor constructed from PC-2 (impregnation ratio of 2), with the highest phosphorus content, can operate very stably in 1 M H2 SO4 at 1.5 V with only 18 % degradation after 10 000 cycles at a current density of 5 A g(-1) . Due to the wide electrochemical window, a supercapacitor assembled with PC-2 has a high energy density of 15 Wh kg(-1) at a power density of 75 W kg(-1) . The possibility of widening the potential window above the theoretical potential for the decomposition of water is attributed to reversible electrochemical hydrogen storage in narrow micropores and the positive effect of phosphorus-rich functional groups, particularly the polyphosphates on the carbon surface. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Remote Monitoring of a Multi-Component Liquid-Phase Organic Synthesis by Infrared Emission Spectroscopy: The Recovery of Pure Component Emissivities by Band-Target Entropy Minimization

    Czech Academy of Sciences Publication Activity Database

    Cheng, S.; Tjahjono, M.; Rajarathnam, D.; Chuanzhao, L.; Lyapkalo, Ilya; Chen, D.; Garland, M.

    2007-01-01

    Roč. 61, č. 10 (2007), s. 1057-1062 ISSN 0003-7028 Institutional research plan: CEZ:AV0Z40550506 Keywords : infrared emission spectroscopy * liquid phase reaction * band-target entropy minimization * BTEM * emittance Subject RIV: CC - Organic Chemistry Impact factor: 1.902, year: 2007

  17. Phosphorus doped TiO2 as oxygen sensor with low operating temperature and sensing mechanism

    International Nuclear Information System (INIS)

    Han, Zhizhong; Wang, Jiejie; Liao, Lan; Pan, Haibo; Shen, Shuifa; Chen, Jianzhong

    2013-01-01

    Nano-scale TiO 2 powders doped with phosphorus were prepared by sol–gel method. The characterization of the materials was performed by XRD, BET, FT-IR spectroscopy, Zeta potential measurement and XPS analysis. The results indicate that the phosphorus suppresses the crystal growth and phase transformation and, at the same time, increases the surface area and enhances the sensitivity and selectivity for the P-doped TiO 2 oxygen sensors. In this system, the operating temperature is low, only 116 °C, and the response time is short. The spectra of FT-IR and XPS show that the phosphorus dopant presents as the pentavalent-oxidation state in TiO 2 , further phosphorus can connect with Ti 4+ through the bond of Ti-O-P. The positive shifts of XPS peaks indicate that electron depleted layer of P-doped TiO 2 is narrowed compared with that of pure TiO 2 , and the results of Zeta potential illuminate that the density of surface charge carrier is intensified. The adsorptive active site and Lewis acid characteristics of the surface are reinforced by phosphorus doping, where phosphorus ions act as a new active site. Thus, the sensitivity of P-doped TiO 2 is improved, and the 5 mol% P-doped sample has the optimal oxygen sensing properties.

  18. Pre-concentration of Cr, Mn, Fe and Co of water sea and analysis by plasma emission spectroscopy - DCP

    International Nuclear Information System (INIS)

    Ferreira, E.M.M.

    1985-01-01

    Studies of separation and pre-concentration methods of chromium, manganese, iron and cobalt from seawater, that allow use control methods of 5 1 Cr, 5 4 Mn, 5 5 , 5 9 Fe, 5 8 , 5 9 Co with a better sensibility and the determination of this elements by atomic absorption spectroscopy or plasma emission spectroscopy are described. This methods of seawater analysis will use near the region of Angra I reactor. (author)

  19. Multi-element analysis of the rat hippocampus by proton induced x-ray emission spectroscopy (phosphorus, sulfur, chlorine, potassium, calcium, iron, zinc, copper, lead, bromine, and rubidium)

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, K.; Danscher, G.

    1979-01-22

    A technique for multi-element analysis of brain tissue by proton induced x-ray emission spectroscopy (PIXE) is described and data from analysis of fixed and unfixed samples from rat hippocampus, neocortex, amygdala, and spinal cord are presented and commented on. The atoms present in the tissue are bombarded with protons which cause the ejection of electrons from the inner shells. When the holes are refilled with electrons from outer shells, x-ray quanta characteristic for each element are emitted. Using a high resolution energy dispersive detector, a complete x-ray spectrum of the specimen can be recorded in a single measurement. Detection limits less than or approximately 5 ppM of dry matter are obtained for most elements with atomic number greater than 14 (silicon). Around 13 elements were found in concentrations above the detection limits. The grand means for non-fixed hippocampi were e.g., for Zn-120 ppM; Rb-20 ppM; Fe-150 ppM; Pb-3 ppM; Ni-5 ppM.

  20. Sargasso Sea phosphorus biogeochemistry: an important role for dissolved organic phosphorus (DOP

    Directory of Open Access Journals (Sweden)

    M. W. Lomas

    2010-02-01

    Full Text Available Inorganic phosphorus (SRP concentrations in the subtropical North Atlantic are some of the lowest in the global ocean and have been hypothesized to constrain primary production. Based upon data from several transect cruises in this region, it has been hypothesized that dissolved organic phosphorus (DOP supports a significant fraction of primary production in the subtropical North Atlantic. In this study, a time-series of phosphorus biogeochemistry is presented for the Bermuda Atlantic Time-series Study site, including rates of phosphorus export. Most parameters have a seasonal pattern, although year-over-year variability in the seasonal pattern is substantial, likely due to differences in external forcing. Suspended particulate phosphorus exhibits a seasonal maximum during the spring bloom, despite the absence of a seasonal peak in SRP. However, DOP concentrations are at an annual maximum prior to the winter/spring bloom and decline over the course of the spring bloom while whole community alkaline phosphatase activities are highest. As a result of DOP bioavailability, the growth of particles during the spring bloom occurs in Redfield proportions, though particles exported from the euphotic zone show rapid and significant remineralization of phosphorus within the first 50 m below the euphotic zone. Based upon DOP data from transect cruises in this region, the southward cross gyral flux of DOP is estimated to support ~25% of annual primary production and ~100% of phosphorus export. These estimates are consistent with other research in the subtropical North Atlantic and reinforce the hypothesis that while the subtropics may be phosphorus stressed (a physiological response to low inorganic phosphorus, utilization of the DOP pool allows production and accumulation of microbial biomass at Redfield proportions.

  1. Nanoparticle Enhanced Laser Induced Breakdown Spectroscopy: Effect of nanoparticles deposited on sample surface on laser ablation and plasma emission

    International Nuclear Information System (INIS)

    De Giacomo, A.; Gaudiuso, R.; Koral, C.; Dell'Aglio, M.; De Pascale, O.

    2014-01-01

    In this paper the use of metallic nanoparticles (NPs) for improving Laser Induced Breakdown Spectroscopy (LIBS) is discussed. In the case of conductors an emission signal enhancement up to 1–2 orders of magnitude was obtained depositing NPs on the sample surface by drying a micro-drop of colloidal solution. The basic mechanisms of Nanoparticle Enhanced LIBS (NELIBS) were studied and the main causes of this significantly large enhancement were found to be related to the effect of NPs on the laser ablation process, in terms of a faster and more efficient production of seed electrons with respect to conventional LIBS. The characteristics of NELIBS-produced plasma were investigated by emission spectroscopy and spectrally resolved images. In spite of similar plasma parameters, the NELIBS plasma was found to have larger emission volume and longer persistence than the LIBS one. A method to determine NP concentration and size was also proposed, which involved depositing NPs on non-interacting substrates, and proved the feasibility of LIBS as a fast detection tool for a preliminary characterization of NPs. - Highlights: • Effect of NPs on sample surface enables instantaneous field emission. • More efficient ablation • LIBS emission enhancement up to 1–2 orders of magnitude • Possibility of NP characterization in terms of concentration and size

  2. How phosphorus limitation can control climate-active gas sources and sinks

    Science.gov (United States)

    Gypens, Nathalie; Borges, Alberto V.; Ghyoot, Caroline

    2017-06-01

    Since the 1950's, anthropogenic activities have increased nutrient river loads to European coastal areas. Subsequent implementation of nutrient reduction policies have led to considerably reduction of phosphorus (P) loads from the mid-1980's, while nitrogen (N) loads were maintained, inducing a P limitation of phytoplankton growth in many eutrophied coastal areas such as the Southern Bight of the North Sea (SBNS). When dissolved inorganic phosphorus (DIP) is limiting, most phytoplankton organisms are able to indirectly acquire P from dissolved organic P (DOP). We investigate the impact of DOP use on phytoplankton production and atmospheric fluxes of CO2 and dimethylsulfide (DMS) in the SBNS from 1951 to 2007 using an extended version of the R-MIRO-BIOGAS model. This model includes a description of the ability of phytoplankton organisms to use DOP as a source of P. Results show that primary production can increase up to 30% due to DOP uptake under limiting DIP conditions. Consequently, simulated DMS emissions also increase proportionally while CO2 emissions to the atmosphere decrease, relative to the reference simulation without DOP uptake.

  3. Phosphorus use efficiency of maize: an investigation using radiotracer phosphorus (32P)

    International Nuclear Information System (INIS)

    Meena, S.

    2017-01-01

    A better understanding on the nutrient uptake and utilization by plants is essential for developing better nutrient efficient cultivars suited for optimal production. Precise information on the PUE of crops and P dynamics can be obtained with the help of radiotracer technique. To study the phosphorus acquisition and phosphorus use efficiency of added sources in maize using 32 P, a pot culture experiment was conducted in a medium P soil (21.26 kg ha -1 ). The treatments were P as Single Superphosphate, Enriched FYM with Single Superphosphate (EFYM), DAP, Nutriseed pack (SSP), Nutriseed pack (DAP). The above treatments were applied along with phosphobacteria. Totally there were ten treatments replicated four times. Phosphorus sources were tagged with 32 P (obtained as 32 P in orthophosphoric medium from the Board of Radiation and Isotope Technology) and applied as per the treatments. Radioactive 32 P in the grain and stover sample was determined using Liquid Scintillation Counter (Perkin Elmer Tricarb 2810 R). Using the data, per cent phosphorus derived from fertilizer (%Pdff), per cent phosphorus derived from soil (%Pdfs), Phosphorus Use Efficiency (PUE) and A value were determined. Application of Phosphorus (SSP, DAP, enriched FYM with SSP, Nutriseed pack (SSP) and Nutriseed pack (DAP)) along with PB increased the per cent phosphorus derived from fertilizer (% Pdff), P uptake from fertilizer and PUE. The highest PUE of 25.38 was recorded in the treatment where enriched FYM with SSP was applied along with PB. (author)

  4. Holographic interferometry as electrochemical emission spectroscopy of carbon steel in seawater with low concentration of RA-41 corrosion inhibitor

    International Nuclear Information System (INIS)

    Habib, K.; Al-Muhana, K.; Habib, A.

    2009-01-01

    In the present investigation, holographic interferometry was utilized for the first time to determine the rate change of the number of the fringe evolutions during the corrosion test of carbon steel in blank seawater and with seawater with different concentrations of a corrosion inhibitor. In other words, the anodic dissolution behaviors (corrosion) of the carbon steel were determined simultaneously by holographic interferometry, an electromagnetic method, and by the electrochemical impedance (EI) spectroscopy, an electronic method. So, the abrupt rate change of the number of the fringe evolutions during corrosion test (EI) spectroscopy, of the carbon steel is called electrochemical emission spectroscopy. The corrosion process of the steel samples was carried out in blank seawater and seawater with different concentrations, 5-20 ppm, of RA-41 corrosion inhibitor using the EI spectroscopy method, at room temperature. The electrochemical emission spectra of the carbon steel in different solutions represent a detailed picture of the rate change of the anodic dissolution of the steel throughout the corrosion processes. Furthermore, the optical interferometry data of the carbon steel were compared to the data, which were obtained from the EI spectroscopy. Consequently, holographic interferometric is found very useful for monitoring the anodic dissolution behaviors of metals, in which the number of the fringe evolutions of the steel samples can be determined in situ. (Author)

  5. The grain boundary segregation of phosphorus in thermally aged and irradiated C-Mn submerged-are weld metal

    International Nuclear Information System (INIS)

    Mendes, C.M.

    1999-01-01

    The segregation of free phosphorus atoms to grain boundaries in C-Mn steels has been identified as an embrittlement mechanism. A change in the brittle fracture mechanism from transgranular to intergranular has been observed for materials with higher phosphorus grain boundary coverage. The grain boundary segregation of phosphorus in various steels used in the nuclear power industry has been thermodynamically and kinetically modelled mostly with the Langmuir-McLean model. Recent publications have also suggested that neutron irradiation can affect segregation and various attempts at modelling this are currently under way. The present paper describes a data base assembled on phosphorus grain boundary coverage measured by Auger electron spectroscopy on thermally aged and irradiated C-Mn submerged-arc weld specimens. Software tools were developed to evaluate the changes in phosphorus grain boundary coverage associated with instantaneous temperature changes and temperature gradients. The phosphorus free energy change associated with grain boundary segregation was modelled from the thermally aged data and used with the software to determine the phosphorus segregation in submerged-arc weld metals following the post weld stress relief heat treatments received prior to plant operation. The phosphorus grain boundary coverage changes arising from the thermal history of submerged-arc weld materials during irradiation were also modelled and found to compare well with data obtained on irradiated materials. It was concluded that under the irradiation conditions sampled, phosphorus grain boundary segregation in submerged-arc weld materials can be modelled successfully using only the thermal term without appealing to an irradiation induced segregation process. (author)

  6. Magnetic resonance spectroscopy and imaging in cerebral ischemia

    International Nuclear Information System (INIS)

    Rijen, P.C. van.

    1991-01-01

    In-vivo proton and phosphorus magnetic resonance spectroscopy was used to detect changes in cerebral metabolism during ischemia and other types of metabolic stress. Magnetic resonance imaging was performed in an animal model to observe morphological alterations during focal cerebral ischemia. Spectroscopy was performed in animal models with global ischemia, in volunteers during hyperventilation and pharmaco-logically altered cerebral perfusion, and in patients with acute and prolonged focal cerebral ischemia. (author). 396 refs.; 44 figs.; 14 tabs

  7. Inductively coupled plasma-atomic emission spectroscopy

    International Nuclear Information System (INIS)

    Winge, R.K.; Fassel, V.A.; Peterson, V.J.; Floyd, M.A.

    1985-01-01

    This atlas of inductively coupled plasma-atomic emission spectroscopy records the spectra of the elements in a way that would reveal the general nature of the spectra, in all their simplicity or complexity; and offers a definitive summary of the most prominent spectral lines of the elements, i.e., those most likely to be useful for the determination of trace and ultratrace concentrations; it provides reliable estimates, based on the recorded experimental spectra, of the powers of detection of the listed prominent lines; and assesses the very important problem of spectral interferences. The atlas is composed of three main sections. Part I is concerned with the historical aspects of compilations of spectral information. Part II is based on 232 wavelength scans of 70 elements. Each of the wavelength scans covers an 80 nm spectral region. These scans allow a rapid comparison of the background and spectral line intensities emitted in the ICP and provide a ready means for identification of the most prominent lines of each element and for estimation of the trace element analytical capabilities of these lines. A listing of 973 prominent lines with associated detection limits is also presented. Part III addresses the problem of spectral interferences. On this topic a detailed collection of coincidence profiles is presented for 281 of the most prominent lines, each with profiles of ten of the most prevalent concomitants superimposed. (Auth.)

  8. Nuclear spectroscopy with Geant4: Proton and neutron emission & radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Sarmiento, L. G., E-mail: Luis.Sarmiento@nuclear.lu.se; Rudolph, D. [Department of Physics, Lund University, 22100 Lund (Sweden)

    2016-07-07

    With the aid of a novel combination of existing equipment – JYFLTRAP and the TASISpec decay station – it is possible to perform very clean quantum-state selective, high-resolution particle-γ decay spectroscopy. We intend to study the determination of the branching ratio of the ℓ = 9 proton emission from the I{sup π} = 19/2{sup −}, 3174-keV isomer in the N = Z − 1 nucleus {sup 53}Co. The study aims to initiate a series of similar experiments along the proton dripline, thereby providing unique insights into “open quantum systems”. The technique has been pioneered in case studies using SHIPTRAP and TASISpec at GSI. Newly available radioactive decay modes in Geant4 simulations are going to corroborate the anticipated experimental results.

  9. Application of optical emission spectroscopy to high current proton sources

    International Nuclear Information System (INIS)

    Castro, G; Mazzaglia, M; Nicolosi, D; Mascali, D; Reitano, R; Celona, L; Leonardi, O; Leone, F; Naselli, E; Neri, L; Torrisi, G; Gammino, S; Zaniol, B

    2017-01-01

    Optical Emission Spectroscopy (OES) represents a very reliable technique to carry out non-invasive measurements of plasma density and plasma temperature in the range of tens of eV. With respect to other diagnostics, it also can characterize the different populations of neutrals and ionized particles constituting the plasma. At INFN-LNS, OES techniques have been developed and applied to characterize the plasma generated by the Flexible Plasma Trap, an ion source used as 'testbench' of the proton source built for European Spallation Source. This work presents the characterization of the parameters of a hydrogen plasma in different conditions of neutral pressure, microwave power and magnetic field profile, along with perspectives for further upgrades of the OES diagnostics system. (paper)

  10. Emission Spectroscopy and Radiometric Measurements in the NASA Ames IHF Arc Jet Facility

    Science.gov (United States)

    Winter, Michael W.; Raiche, George A.; Prabhu, Dinesh K.

    2012-01-01

    Plasma diagnostic measurement campaigns in the NASA Ames Interaction Heating Facility (IHF) have been conducted over the last several years with a view towards characterizing the flow in the arc jet facility by providing data necessary for modeling and simulation. Optical emission spectroscopy has been used in the plenum and in the free jet of the nozzle. Radiation incident over a probe surface has also been measured using radiometry. Plenum measurements have shown distinct radial profiles of temperature over a range of operating conditions. For cases where large amounts of cold air are added radially to the main arc-heated stream, the temperature profiles are higher by as much as 1500 K than the profiles assumed in flow simulations. Optical measurements perpendicular to the flow direction in the free jet showed significant contributions to the molecule emission through inverse pre-dissociation, thus allowing determination of atom number densities from molecular emission. This has been preliminarily demonstrated with the N2 1st Positive System. Despite the use of older rate coefficients, the resulting atom densities are reasonable and surprisingly close to flow predictions.

  11. Emission spectroscopy of highly ionized high-temperature plasma jets

    Energy Technology Data Exchange (ETDEWEB)

    Belevtsev, A A; Chinnov, V F; Isakaev, E Kh [Associated Institute for High Temperatures, Russian Academy of Sciences Izhorskaya 13/19, Moscow, 125412 (Russian Federation)

    2006-08-01

    This paper deals with advanced studies on the optical emission spectroscopy of atmospheric pressure highly ionized high-temperature argon and nitrogen plasma jets generated by a powerful arc plasmatron. The emission spectra are taken in the 200-1000 nm range with a spectral resolution of {approx}0.01-0.02 nm. The exposure times are 6 x 10{sup -6}-2 x 10{sup -2} s, the spatial resolution is 0.02-0.03 mm. The recorded jet spectra are abundant in spectral lines originating from different ionization stages. In nitrogen plasmas, tens of vibronic bands are also observed. To interpret and process these spectra such that plasma characteristics can be derived, a purpose-developed automated processing system is applied. The use of a CCD camera at the spectrograph output allows a simultaneous recording of the spectral and chord intensity distributions of spectral lines, which can yet belong to the overlapped spectra of the first and second orders of interference. The modern optical diagnostic means and methods used permit the determination of spatial distributions of electron number densities and temperatures and evaluation of rotational temperatures. The radial profiles of the irradiating plasma components can also be obtained. Special attention is given to the method of deriving rotational temperatures using vibronic bands with an incompletely identified rotational structure.

  12. Towards global phosphorus security: A systems framework for phosphorus recovery and reuse options

    NARCIS (Netherlands)

    Cordell, D.; Rosemarin, A.; Schroder, J.J.; Smit, A.L.

    2011-01-01

    Human intervention in the global phosphorus cycle has mobilised nearly half a billion tonnes of the element from phosphate rock into the hydrosphere over the past half century. The resultant water pollution concerns have been the main driver for sustainable phosphorus use (including phosphorus

  13. Effect of supplemented fungal phytase on performance and phosphorus availability by phosphorus-depleted juvenile rainbow trout (Oncorhynchus mykiss), and on the magnitude and composition of phosphorus waste output

    DEFF Research Database (Denmark)

    Dalsgaard, Anne Johanne Tang; Schøn Ekmann, K.; Pedersen, Per Bovbjerg

    2009-01-01

    The effect of a supplemental fungal phytase on performance and phosphorus availability by juvenile rainbow trout fed diets with a high inclusion of plant based protein and on the magnitude and composition of the waste phosphorus production was tested in a 2 × 3 factorial design at a temperature....../suspended phosphorus waste output from fish fed the phytase supplemented diet containing 0.71% available phosphorus, suggesting that the phosphorus requirement was reached at this phosphorus level. Consistent with this, there was a substantial increase in the dissolved/suspended phosphorus waste output from fish fed...... the phytase supplemented diet containing 0.81% available phosphorus, suggesting that the phosphorus requirement was exceeded in this group. This study demonstrated that phytase supplementation will be advantageous to the fish and the environment if supplemented to low-phosphorus diets containing a large share...

  14. Effects of phosphorus on the electrical characteristics of plasma deposited hydrogenated amorphous silicon carbide thin films

    Science.gov (United States)

    Alcinkaya, Burak; Sel, Kivanc

    2018-01-01

    The properties of phosphorus doped hydrogenated amorphous silicon carbide (a-SiCx:H) thin films, that were deposited by plasma enhanced chemical vapor deposition technique with four different carbon contents (x), were analyzed and compared with those of the intrinsic a-SiCx:H thin films. The carbon contents of the films were determined by X-ray photoelectron spectroscopy. The thickness and optical energies, such as Tauc, E04 and Urbach energies, of the thin films were determined by UV-Visible transmittance spectroscopy. The electrical properties of the films, such as conductivities and activation energies were analyzed by temperature dependent current-voltage measurements. Finally, the conduction mechanisms of the films were investigated by numerical analysis, in which the standard transport mechanism in the extended states and the nearest neighbor hopping mechanism in the band tail states were taken into consideration. It was determined that, by the effect of phosphorus doping the dominant conduction mechanism was the standard transport mechanism for all carbon contents.

  15. Status of electron temperature and density measurement with beam emission spectroscopy on thermal helium at TEXTOR

    NARCIS (Netherlands)

    Schmitz, O.; Beigman, I. L.; Vainshtein, L. A.; Schweer, B.; Kantor, M.; Pospieszczyk, A.; Xu, Y.; Krychowiak, M.; Lehnen, M.; Samm, U.; Unterberg, B.

    2008-01-01

    Beam emission spectroscopy on thermal helium is used at the TEXTOR tokamak as a reliable method to obtain radial profiles of electron temperature T-e(r, t) and electron density ne(r, t). In this paper the experimental realization of this method at TEXTOR and the status of the atomic physics employed

  16. Hydrothermal synthesis of hydroxyapatite nanorods using pyridoxal-5′-phosphate as a phosphorus source

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xin-Yu; Zhu, Ying-Jie, E-mail: y.j.zhu@mail.sic.ac.cn; Lu, Bing-Qiang; Chen, Feng; Qi, Chao; Zhao, Jing; Wu, Jin

    2014-07-01

    Graphical abstract: Hydroxyapatite nanorods are synthesized using biocompatible biomolecule pyridoxal-5′-phosphate as a new organic phosphorus source by the hydrothermal method. - Highlights: • Hydrothermal synthesis of hydroxyapatite nanorods is reported. • Biocompatible pyridoxal-5′-phosphate is used as an organic phosphorus source. • This method is simple, surfactant-free and environmentally friendly. - Abstract: Hydroxyapatite nanorods are synthesized by the hydrothermal method using biocompatible biomolecule pyridoxal-5′-phosphate (PLP) as a new organic phosphorus source. In this method, PLP biomolecules are hydrolyzed to produce phosphate ions under hydrothermal conditions, and these phosphate ions react with pre-existing calcium ions to form hydroxyapatite nanorods. The effects of experimental conditions including hydrothermal temperature and time on the morphology and crystal phase of the products are investigated. This method is simple, surfactant-free and environmentally friendly. The products are characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric (TG) analysis.

  17. A model study of warming-induced phosphorus-oxygen feedbacks in open-ocean oxygen minimum zones on millennial timescales

    Science.gov (United States)

    Niemeyer, Daniela; Kemena, Tronje P.; Meissner, Katrin J.; Oschlies, Andreas

    2017-05-01

    Observations indicate an expansion of oxygen minimum zones (OMZs) over the past 50 years, likely related to ongoing deoxygenation caused by reduced oxygen solubility, changes in stratification and circulation, and a potential acceleration of organic matter turnover in a warming climate. The overall area of ocean sediments that are in direct contact with low-oxygen bottom waters also increases with expanding OMZs. This leads to a release of phosphorus from ocean sediments. If anthropogenic carbon dioxide emissions continue unabated, higher temperatures will cause enhanced weathering on land, which, in turn, will increase the phosphorus and alkalinity fluxes into the ocean and therefore raise the ocean's phosphorus inventory even further. A higher availability of phosphorus enhances biological production, remineralisation and oxygen consumption, and might therefore lead to further expansions of OMZs, representing a positive feedback. A negative feedback arises from the enhanced productivity-induced drawdown of carbon and also increased uptake of CO2 due to weathering-induced alkalinity input. This feedback leads to a decrease in atmospheric CO2 and weathering rates. Here, we quantify these two competing feedbacks on millennial timescales for a high CO2 emission scenario. Using the University of Victoria (UVic) Earth System Climate Model of intermediate complexity, our model results suggest that the positive benthic phosphorus release feedback has only a minor impact on the size of OMZs in the next 1000 years. The increase in the marine phosphorus inventory under assumed business-as-usual global warming conditions originates, on millennial timescales, almost exclusively (> 80 %) from the input via terrestrial weathering and causes a 4- to 5-fold expansion of the suboxic water volume in the model.

  18. Relation of ductile-to-brittle transition temperature to phosphorus grain boundary segregation for a Ti-stabilized interstitial free steel

    International Nuclear Information System (INIS)

    Chen, X.-M.; Song, S.-H.; Weng, L.-Q.; Liu, S.-J.; Wang, K.

    2011-01-01

    Highlights: → The free energy of phosphorus grain boundary segregation in IF steel is ∼44.8 kJ/mol. → A relationship between DBTT and phosphorus segregation is established. → The DBTT increases linearly with increasing phosphorus boundary concentration. → Cold work embrittlement may be severe if the steel is annealed at relatively low temperatures. - Abstract: Equilibrium grain boundary segregation of phosphorus in a Ti-stabilized interstitial free (IF) steel is measured using Auger electron spectroscopy (AES) after the specimens are aged for adequate time at different temperatures between 600 and 850 deg. C. Based on the experimental data of equilibrium grain boundary segregation along with the McLean equilibrium segregation theory, the free energy of segregation of phosphorus is evaluated to be ∼44.8 kJ/mol, being independent of temperature. With the AES results being combined with the ductile-to-brittle transition temperatures (DBTTs) determined by impact tests, a relationship between DBTT and phosphorus boundary concentration is established. Predictions with the relationship indicate that cold work embrittlement may be severe if the steel is annealed at relatively low temperatures after cold rolling.

  19. Mineral distribution in rice: Measurement by Microwave Plasma Atomic Emission Spectroscopy (MP-AES)

    International Nuclear Information System (INIS)

    Ramos, Nerissa C.; Ramos, R.G.A.; Quirit, L.L.; Arcilla, C.A.

    2015-01-01

    Microwave Plasma Atomic Emission Spectroscopy (MP-AES) is a new technology with comparable performance and sensitivity to Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Both instrument use plasma as the energy source that produces atomic and ionic emission lines. However, MP-AES uses nitrogen as the plasma gas instead of argon which is an additional expense for ICP-OES. Thus, MP-AES is more economical. This study quantified six essential minerals (Se, Zn, Fe, Cu, Mn and K) in rice using MP-AES. Hot plate digestion was used for sample extraction and the detection limit for each instrument was compared with respect to the requirement for routine analysis in rice. Black, red and non-pigmented rice samples were polished in various intervals to determine the concentration loss of minerals. The polishing time corresponds to the structure of the rice grains such as outer bran layer (0 to 15), inner bran layer (15 to 30), outer endosperm layer (30 to 45), and middle endosperm layer (45 to 60). Results of MP-AES analysis showed that black rice had all essential materials (except K) in high concentration at the outer bran layer. The red and non-pigmented rice samples on the other hand, contained high levels of Se, Zn, Fe, and Mn in the whole bran portion. After 25 seconds, the mineral concentrations remained constant. The concentration of Cu however, gave consistent value in all polishing intervals, hence Cu might be located in the inner endosperm layer. Results also showed that K was uniformly distributed in all samples where 5% loss was consistently observed for every polishing interval. Therefore, the concentration of K was also affected by polishing time. Thus, the new MP-AES technology with comparable performance to ICP-OES is a promising tool for routine analysis in rice. (author)

  20. III. Quantitative aspects of phosphorus excretionin ruminants

    OpenAIRE

    Bravo , David; Sauvant , Daniel; Bogaert , Catherine; Meschy , François

    2003-01-01

    International audience; Ruminant phosphorus excretion and metabolism were studied through a database. Faecal endogenous phosphorus is the main pathway of phosphorus excretion and averages 0.85 of total faecal phosphorus. The remaining 0.15 is unabsorbed dietary phosphorus. Faecal endogenous phosphorus is mainly unabsorbed phosphorus, with saliva being the major source, and is correlated to factors influencing saliva secretion (DM intake, physical dietary characteristics and dietary phosphorus...

  1. Laser induced aluminiun plasma analysis by optical emission spectroscopy in a nitrogen background gas

    International Nuclear Information System (INIS)

    Chamorro, J C; Uzuriaga, J; Riascos, H

    2012-01-01

    We studied an Al plasma generated by a Nd:YAG laser with a laser fluence of 4 J/cm 2 , a wavelength of 1064 nm, energy pulse of 500 mJ and 10 Hz repetition rate. We studied their spectral characteristics at various ambient nitrogen pressures by optical emission spectroscopy (OES). The N 2 gas pressure was varied from 20 mTorr to 150 mTorr. In Al plume, both atomic and ionic spectra were observed. The electron temperature and electron number density of the plume as of the function ambient gas pressure were determined. The electron temperature was calculated by using the Boltzmann-plot method and the number density was calculated considering the stark effect as dominating on the emission lines.

  2. Determining the phonon energy of highly oriented pyrolytic graphite by scanning tunneling microscope light emission spectroscopy

    Science.gov (United States)

    Uehara, Yoichi; Michimata, Junichi; Watanabe, Shota; Katano, Satoshi; Inaoka, Takeshi

    2018-03-01

    We have investigated the scanning tunneling microscope (STM) light emission spectra of isolated single Ag nanoparticles lying on highly oriented pyrolytic graphite (HOPG). The STM light emission spectra exhibited two types of spectral structures (step-like and periodic). Comparisons of the observed structures and theoretical predictions indicate that the phonon energy of the ZO mode of HOPG [M. Mohr et al., Phys. Rev. B 76, 035439 (2007)] can be determined from the energy difference between the cutoff of STM light emission and the step in the former structure, and from the period of the latter structure. Since the role of the Ag nanoparticles does not depend on the substrate materials, this method will enable the phonon energies of various materials to be measured by STM light emission spectroscopy. The spatial resolution is comparable to the lateral size of the individual Ag nanoparticles (that is, a few nm).

  3. Phosphorus blood test

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003478.htm Phosphorus blood test To use the sharing features on this page, please enable JavaScript. The phosphorus blood test measures the amount of phosphate in the blood. ...

  4. Phosphorus Dendrimers as Carriers of siRNA—Characterisation of Dendriplexes

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Majoral

    2013-04-01

    Full Text Available There are many types of dendrimers used as nanomolecules for gene delivery but there is still an ongoing search for ones that are able to effectively deliver drugs to cells. The possibility of gene silencing using siRNA gives hope for effective treatment of numerous diseases. The aim of this work was to investigate in vitro biophysical properties of dendriplexes formed by siRNA and cationic phosphorus dendrimers of 3rd and 4th generation. First, using the ethidium bromide intercalation method, it was examined whether dendrimers have an ability to form complexes with siRNA. Next, the characterisation of dendriplexes formed at different molar ratios was carried out using biophysical methods. The effects of zeta potential, size and changes of siRNA conformation on the complexation with dendrimers were examined. It was found that both phosphorus dendrimers interacted with siRNA. The zeta potential values of dendriplexes ranged from negative to positive and the hydrodynamic diameter depended on the number of dendrimer molecules in the complex. Furthermore, using circular dichroism spectroscopy it was found that cationic phosphorus dendrimers changed only slightly the shape of siRNA CD spectra, thus they did not induce significant changes in the nucleic acid secondary structure during complex formation.

  5. Phosphorus speciation and solubility in aeolian dust deposited in the interior American West

    Science.gov (United States)

    Zhang, Zhuojun; Goldstein, Harland L.; Reynolds, Richard L.; Hu, Yongfeng; Wang, Xiaoming; Zhu, Mengqiang

    2018-01-01

    Aeolian dust is a significant source of phosphorus (P) to alpine oligotrophic lakes, but P speciation in dust and source sediments and its release kinetics to lake water remain unknown. Phosphorus K-edge XANES spectroscopy shows that calcium-bound P (Ca−P) is dominant in 10 of 12 dust samples (41−74%) deposited on snow in the central Rocky Mountains and all 42 source sediment samples (the fine fraction) (68−80%), with a lower proportion in dust probably because acidic snowmelt dissolves some Ca−P in dust before collection. Iron-bound P (Fe−P, ∼54%) dominates in the remaining two dust samples. Chemical extractions (SEDEX) on these samples provide inaccurate results because of unselective extraction of targeted species and

  6. Screening crops for efficient phosphorus acquisition in a low phosphorus soil using radiotracer technique

    International Nuclear Information System (INIS)

    Meena, S.; Malarvizhi, P.; Rajeswari, R.

    2017-01-01

    Deficiency of phosphorus (P) is the major limitation to agricultural production. Identification of cultivars with greater capacity to grow in soils having low P availability (phosphorus efficiency) will help in P management in a sustainable way. Green house experiment with maize (CO 6) and cotton (MCU 13) as test crops with four levels of phosphorus (0, 3.75, 7.50 and 15 mg P kg -1 soil) was conducted in a P deficient soil (7.2 kg ha -1 ) to study the phosphorus acquisition characteristics and to select efficient crop using 32 P radiotracer technique. Carrier free 32 P obtained as orthophosphoric acid in dilute hydrochloric acid medium from the Board of Radiation and Isotope Technology, Mumbai was used for labeling the soil @ 3200 kBq pot -1 . After 60 days the crops were harvested and the radioactivity was measured in the plant samples using Liquid scintillation counter (PerkinElmer - Tricarb 2810 TR). Different values of specific radioactivity and Isotopically Exchangeable Phosphorus for maize and cotton indicated that chemically different pools of soil P were utilized and maize accessing a larger pool than cotton. Maize having recorded high Phosphorus Use Efficiency, Phosphorus Efficiency and low Phosphorus Stress Factor values, it is a better choice for P deficient soils. Higher Phosphorus Acquisition Efficiency of maize (59 %) than cotton (48%) can be related to the ability of maize to take up P from insoluble inorganic P forms. (author)

  7. Preparation and properties of novel epoxy/graphene oxide nanosheets (GON) composites functionalized with flame retardant containing phosphorus and silicon

    International Nuclear Information System (INIS)

    Li, Kuo-Yi; Kuan, Chen-Feng; Kuan, Hsu-Chiang; Chen, Chia-Hsun; Shen, Ming-Yuan; Yang, Jia-Ming; Chiang, Chin-Lung

    2014-01-01

    2-(Diphenylphosphino)ethyltriethoxy silane (DPPES) was grafted onto the surface of graphene oxide nanosheets (GON) via a condensation reaction. X-ray photoelectron spectroscopy, X-ray diffractometry, Fourier transform infrared spectroscopy and Raman spectroscopy verify that DPPES did not only covalently bond to GON as a functionalization moiety, but partly restored its conjugated structure as a reducing agent. DPPES on graphene sheets oxide was observed by transmission electron microscopy, and contributed to the favorable dispersion of DPPES-GON in nonpolar toluene. Additionally, the flame retardancy and thermal stability of epoxy/DPPES-GON nanocomposites that contain various weight fractions of DPPES-GON were studied using the limiting oxygen index test, UL-94 test and by thermogravimetric analysis in nitrogen. The composites containing 10 wt% DPPES-GON can pass V-0 rating in UL-94 test. Adding 10 wt% DPPES-GON in epoxy greatly increased the char yield and LOI by 42% and 80%, respectively. Epoxy/DPPES-GON nanocomposites with phosphorus, silicon and graphene layer structures were found to exhibit much greater flame retardancy than neat epoxy. The synergistic effects among silicon, phosphorus and GON can improve the flame retardancy of epoxy resin. - Highlights: • Flame retardant was grafted on the surface of graphene oxide nanosheets (GON) by the condensation reaction. • The synergistic effect between silicon, phosphorus and GON improved the flame retardance of epoxy resin. • Epoxy composites have excellent flame retardance at low additive concentrations

  8. Green residues from Bangkok green space for renewable energy recovery, phosphorus recycling and greenhouse gases emission reduction.

    Science.gov (United States)

    Thitanuwat, Bussarakam; Polprasert, Chongchin; Englande, Andrew J

    2017-03-01

    Effective ways to integrate human life quality, environmental pollution mitigation and efficient waste management strategies are becoming a crisis challenge for sustainable urban development. The aims of this study are: (1) to evaluate and recommend an optimum Urban Green Space (UGS) area for the Bangkok Metropolitan Administration (BMA); and (2) to quantify potential renewable resources including electricity generation and potential nutrient recovery from generated ash. Green House Gases (GHGs) emissions from the management of Green Residues (GR) produced in a recommended UGS expansion are estimated and compared with those from the existing BMA waste management practice. Results obtained from this study indicate that an increase in UGS from its current 2.02% to 22.4% of the BMA urban area is recommended. This optimum value is primarily due to the area needed as living space for its population. At this scale, GR produced of about 334kt·y -1 may be used to generate electricity at the rate of 206GWh·y -1 by employing incineration technology. Additionally, instead of going to landfill, phosphorus (P) contained in the ash of 1077 t P·y -1 could be recovered to produce P fertilizer to be recycled for agricultural cultivation. Income earned from selling these products is found to offset all of the operational cost of the proposed GR management methodology itself plus 7% of the cost of BMA's Municipal Solid Waste (MSW) operations. About 70% of the current GHGs emission may be reduced based on incineration simulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Bronx River bed sediments phosphorus pool and phosphorus compound identification

    Science.gov (United States)

    Wang, J.; Pant, H. K.

    2008-12-01

    Phosphorus (P) transport in the Bronx River degraded water quality, decreased oxygen levels, and resulted in bioaccumulation in sediment potentially resulting in eutrophication, algal blooms and oxygen depletion under certain temperature and pH conditions. The anthropogenic P sources are storm water runoff, raw sewage discharge, fertilizer application in lawn, golf course and New York Botanical Garden; manure from the Bronx zoo; combined sewoverflows (CSO's) from parkway and Hunts Point sewage plant; pollutants from East River. This research was conducted in the urban river system in New York City area, in order to control P source, figure out P transport temporal and spatial variations and the impact on water quality; aimed to regulate P application, sharing data with Bronx River Alliance, EPA, DEP and DEC. The sediment characteristics influence the distribution and bioavailbility of P in the Bronx River. The P sequential extraction gave the quantitative analysis of the P pool, quantifying the inorganic and organic P from the sediments. There were different P pool patterns at the 15 sites, and the substantial amount of inorganic P pool indicated that a large amount P is bioavailable. The 31P- NMR (Nuclear Magnetic Resonance Spectroscopy) technology had been used to identify P species in the 15 sites of the Bronx River, which gave a qualitative analysis on phosphorus transport in the river. The P compounds in the Bronx River bed sediments are mostly glycerophophate (GlyP), nucleoside monophosphates (NMP), polynucleotides (PolyN), and few sites showed the small amount of glucose-6-phosphate (G6P), glycerophosphoethanoamine (GPEA), phosphoenopyruvates (PEP), and inosine monophosphate (IMP). The land use spatial and temporal variations influence local water P levels, P distributions, and P compositions.

  10. Investigations of the cathode region of an argon arc plasma by degenerate four-wave mixing laser spectroscopy and optical emission spectroscopy

    International Nuclear Information System (INIS)

    Dzierzega, K; Pokrzywka, B; Pellerin, S

    2004-01-01

    Degenerate four-wave mixing (DFWM) laser spectroscopy was used in local studies of atmospheric pressure argon plasma generated in a free-burning arc. The results of plasma diagnostics using the DFWM method were compared to the results obtained with optical emission measurements. In the cathode region of the arc the maxima of both the DFWM signal and the emission coefficient for the 696.5 nm Ar I line depend on the distance from the cathode tip. This effect proves the departure of the plasma state from local thermal equilibrium (LTE) as it has been reported by many authors. On the other hand the Stark shifts of the 696.5 nm Ar I line determined by the DFWM method in relation to plasma diagnostic results show no deviations from LTE on the arc axis down to 1.0 mm from the cathode tip

  11. Effects of phosphorus availability and genetic variation of leaf terpene content and emission rate in Pinus pinaster seedlings susceptible and resistant to the pine weevil, Hylobius abietis.

    Science.gov (United States)

    Blanch, J-S; Sampedro, L; Llusià, J; Moreira, X; Zas, R; Peñuelas, J

    2012-03-01

    We studied the effects of phosphorus fertilisation on foliar terpene concentrations and foliar volatile terpene emission rates in six half-sib families of Pinus pinaster Ait. seedlings. Half of the seedlings were resistant to attack of the pine weevil Hylobius abietis L., a generalist phloem feeder, and the remaining seedlings were susceptible to this insect. We hypothesised that P stress could modify the terpene concentration in the needles and thus lead to altered terpene emission patterns relevant to plant-insect signalling. The total concentration and emission rate ranged between 5732 and 13,995 μg·g(-1) DW and between 2 and 22 μg·g(-1) DW·h(-1), respectively. Storage and emission were dominated by the isomers α- and β-pinene (77.2% and 84.2% of the total terpene amount amassed and released, respectively). In both resistant and susceptible families, P stress caused an increase of 31% in foliar terpene concentration with an associated 5-fold decrease in terpene emission rates. A higher terpene content in the leaves implies that the 'excess carbon', available under limiting growth conditions (P scarcity), is allocated to terpene production. Sensitive families showed a greater increase in terpene emission rates with increasing P concentrations, which could explain their susceptibility to H. abietis. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

  12. Comparison of three persulfate digestion methods for total phosphorus analysis and estimation of suspended sediments

    International Nuclear Information System (INIS)

    Dayton, Elizabeth Ann; Whitacre, Shane; Holloman, Christopher

    2017-01-01

    As a result of impairments to fresh surface water quality due to phosphorus enrichment, substantial research effort has been put forth to quantify agricultural runoff phosphorus as related to on-field practices. While the analysis of runoff dissolved phosphorus is well prescribed and leaves little room for variability in methodology, there are several methods and variations of sample preparation reagents as well as analysis procedures for determining runoff total phosphorus. Due to the variation in methodology for determination of total phosphorus and an additional laboratory procedure required to measure suspended solids, the objectives of the current study are to i. compare the performance of three persulfate digestion methods (Acid Persulfate, USGS, and Alkaline Persulfate) for total phosphorus percent recovery across a wide range of suspended sediments (SS), and ii. evaluate the ability of using Al and/or Fe in digestion solution to predict SS as a surrogate to the traditional gravimetric method. Percent recovery of total phosphorus was determined using suspensions prepared from soils collected from 21 agricultural fields in Ohio. The Acid Persulfate method was most effective, with an average total phosphorus percent recovery of 96.6%. The second most effective method was the USGS with an average total phosphorus recovery of 76.1%. However, the Alkaline Persulfate method performed poorly with an average 24.5% total phosphorus recovery. As a result application of Alkaline Persulfate digestion to edge of field monitoring may drastically underestimated runoff total phosphorus. In addition to excellent recovery of total phosphorus, the Acid Persulfate method combined with analysis of Al and Fe by inductively coupled plasma atomic emission spectrometry provides a robust estimate of total SS. Due to the large quantity of samples that can result from water quality monitoring, an indirect measure of total SS could be very valuable when time and budget constraints limit

  13. Process control of high rate microcrystalline silicon based solar cell deposition by optical emission spectroscopy

    International Nuclear Information System (INIS)

    Kilper, T.; Donker, M.N. van den; Carius, R.; Rech, B.; Braeuer, G.; Repmann, T.

    2008-01-01

    Silicon thin-film solar cells based on microcrystalline silicon (μc-Si:H) were prepared in a 30 x 30 cm 2 plasma-enhanced chemical vapor deposition reactor using 13.56 or 40.68 MHz plasma excitation frequency. Plasma emission was recorded by optical emission spectroscopy during μc-Si:H absorber layer deposition at deposition rates between 0.5 and 2.5 nm/s. The time course of SiH * and H β emission indicated strong drifts in the process conditions particularly at low total gas flows. By actively controlling the SiH 4 gas flow, the observed process drifts were successfully suppressed resulting in a more homogeneous i-layer crystallinity along the growth direction. In a deposition regime with efficient usage of the process gas, the μc-Si:H solar cell efficiency was enhanced from 7.9 % up to 8.8 % by applying process control

  14. Dietary phosphorus acutely impairs endothelial function.

    Science.gov (United States)

    Shuto, Emi; Taketani, Yutaka; Tanaka, Rieko; Harada, Nagakatsu; Isshiki, Masashi; Sato, Minako; Nashiki, Kunitaka; Amo, Kikuko; Yamamoto, Hironori; Higashi, Yukihito; Nakaya, Yutaka; Takeda, Eiji

    2009-07-01

    Excessive dietary phosphorus may increase cardiovascular risk in healthy individuals as well as in patients with chronic kidney disease, but the mechanisms underlying this risk are not completely understood. To determine whether postprandial hyperphosphatemia may promote endothelial dysfunction, we investigated the acute effect of phosphorus loading on endothelial function in vitro and in vivo. Exposing bovine aortic endothelial cells to a phosphorus load increased production of reactive oxygen species, which depended on phosphorus influx via sodium-dependent phosphate transporters, and decreased nitric oxide production via inhibitory phosphorylation of endothelial nitric oxide synthase. Phosphorus loading inhibited endothelium-dependent vasodilation of rat aortic rings. In 11 healthy men, we alternately served meals containing 400 mg or 1200 mg of phosphorus in a double-blind crossover study and measured flow-mediated dilation of the brachial artery before and 2 h after the meals. The high dietary phosphorus load increased serum phosphorus at 2 h and significantly decreased flow-mediated dilation. Flow-mediated dilation correlated inversely with serum phosphorus. Taken together, these findings suggest that endothelial dysfunction mediated by acute postprandial hyperphosphatemia may contribute to the relationship between serum phosphorus level and the risk for cardiovascular morbidity and mortality.

  15. Effect of phosphorus stress on Microcystis aeruginosa growth and phosphorus uptake.

    Directory of Open Access Journals (Sweden)

    Sajeela Ghaffar

    Full Text Available This study was designed to advance understanding of phosphorus regulation of Microcystis aeruginosa growth, phosphorus uptake and storage in changing phosphorus (P conditions as would occur in lakes. We hypothesized that Microcystis growth and nutrient uptake would fit classic models by Monod, Droop, and Michaelis-Menten in these changing conditions. Microcystis grown in luxury nutrient concentrations was transferred to treatments with phosphorus concentrations ranging from 0-256 μg P∙L-1 and luxury nitrogen. Dissolved phosphorus concentration, cell phosphorus quota, P uptake rate and cell densities were measured at day 3 and 6. Results showed little relationship to predicted models. Microcystis growth was asymptotically related to P treatment from day 0-3, fitting Monod model well, but negatively related to P treatment and cell quota from day 3-6. From day 0-3, cell quota was negatively related to P treatments at <2 μg∙L-1, but increased slightly at higher P. Cell quota decreased greatly in low P treatments from day 3-6, which may have enabled high growths in low P treatments. P uptake was positively and linearly related to P treatment during both periods. Negative uptake rates and increases in measured culture phosphorus concentrations to 5 μg∙L-1 in the lowest P treatments indicated P leaked from cells into culture medium. This leakage during early stages of the experiment may have been sufficient to stimulate metabolism and use of intracellular P stores in low P treatments for rapid growth. Our study shows P regulation of Microcystis growth can be complex as a result of changing P concentrations, and this complexity may be important for modeling Microcystis for nutrient and ecosystem management.

  16. Laser induced breakdown spectroscopy (LIBS) as a rapid tool for material analysis

    International Nuclear Information System (INIS)

    Hussain, T; Gondal, M A

    2013-01-01

    Laser induced breakdown spectroscopy (LIBS) is a novel technique for elemental analysis based on laser-generated plasma. In this technique, laser pulses are applied for ablation of the sample, resulting in the vaporization and ionization of sample in hot plasma which is finally analyzed by the spectrometer. The elements are identified by their unique spectral signatures. LIBS system was developed for elemental analysis of solid and liquid samples. The developed system was applied for qualitative as well as quantitative measurement of elemental concentration present in iron slag and open pit ore samples. The plasma was generated by focusing a pulsed Nd:YAG laser at 1064 nm on test samples to study the capabilities of LIBS as a rapid tool for material analysis. The concentrations of various elements of environmental significance such as cadmium, calcium, magnesium, chromium, manganese, titanium, barium, phosphorus, copper, iron, zinc etc., in these samples were determined. Optimal experimental conditions were evaluated for improving the sensitivity of developed LIBS system through parametric dependence study. The laser-induced breakdown spectroscopy (LIBS) results were compared with the results obtained using standard analytical technique such as inductively couple plasma emission spectroscopy (ICP). Limit of detection (LOD) of our LIBS system were also estimated for the above mentioned elements. This study demonstrates that LIBS could be highly appropriate for rapid online analysis of iron slag and open pit waste.

  17. Laser induced breakdown spectroscopy (LIBS) as a rapid tool for material analysis

    Science.gov (United States)

    Hussain, T.; Gondal, M. A.

    2013-06-01

    Laser induced breakdown spectroscopy (LIBS) is a novel technique for elemental analysis based on laser-generated plasma. In this technique, laser pulses are applied for ablation of the sample, resulting in the vaporization and ionization of sample in hot plasma which is finally analyzed by the spectrometer. The elements are identified by their unique spectral signatures. LIBS system was developed for elemental analysis of solid and liquid samples. The developed system was applied for qualitative as well as quantitative measurement of elemental concentration present in iron slag and open pit ore samples. The plasma was generated by focusing a pulsed Nd:YAG laser at 1064 nm on test samples to study the capabilities of LIBS as a rapid tool for material analysis. The concentrations of various elements of environmental significance such as cadmium, calcium, magnesium, chromium, manganese, titanium, barium, phosphorus, copper, iron, zinc etc., in these samples were determined. Optimal experimental conditions were evaluated for improving the sensitivity of developed LIBS system through parametric dependence study. The laser-induced breakdown spectroscopy (LIBS) results were compared with the results obtained using standard analytical technique such as inductively couple plasma emission spectroscopy (ICP). Limit of detection (LOD) of our LIBS system were also estimated for the above mentioned elements. This study demonstrates that LIBS could be highly appropriate for rapid online analysis of iron slag and open pit waste.

  18. Optical emission spectroscopy of carbon laser plasma ion source

    Science.gov (United States)

    Balki, Oguzhan; Rahman, Md. Mahmudur; Elsayed-Ali, Hani E.

    2018-04-01

    Carbon laser plasma generated by an Nd:YAG laser (wavelength 1064 nm, pulse width 7 ns, fluence 4-52 J cm-2) is studied by optical emission spectroscopy and ion time-of-flight. Up to C4+ ions are detected with the ion flux strongly dependent on the laser fluence. The increase in ion charge with the laser fluence is accompanied by observation of multicharged ion lines in the optical spectra. The time-integrated electron temperature Te is calculated from the Boltzmann plot using the C II lines at 392.0, 426.7, and 588.9 nm. Te is found to increase from ∼0.83 eV for a laser fluence of 22 J cm-2 to ∼0.90 eV for 40 J cm-2. The electron density ne is obtained from the Stark broadened profiles of the C II line at 392 nm and is found to increase from ∼ 2 . 1 × 1017cm-3 for 4 J cm-2 to ∼ 3 . 5 × 1017cm-3 for 40 J cm-2. Applying an external electric field parallel to the expanding plume shows no effect on the line emission intensities. Deconvolution of ion time-of-flight signal with a shifted Maxwell-Boltzmann distribution for each charge state results in an ion temperature Ti ∼4.7 and ∼6.0 eV for 20 and 36 J cm-2, respectively.

  19. Development of a Reference Database for Particle Induced Gamma Ray Emission (PIGE) Spectroscopy

    International Nuclear Information System (INIS)

    2017-09-01

    Ion beam analysis techniques are non-destructive analytical techniques used to identify the composition and structure of surface layers of materials. The applications of these techniques span environmental control, cultural heritage and conservation, materials and fusion technologies. The particle-induced gamma-ray emission (PIGE) spectroscopy technique in particular, is a powerful tool for detecting light elements in certain depths of surface layers. This publication describes the coordinated effort to measure and compile cross section data relevant to PIGE analysis and make these data available to the community of practice through a comprehensive online database.

  20. Can non-point pollutions emissions from agriculture be regulated efficiently using input-output taxes?

    DEFF Research Database (Denmark)

    Hansen, Line Block; Gårn Hansen, Lars

    2014-01-01

    In many parts of Europe and North America, phosphorus loss from cultivated fields is threatening natural ecosystems. Though there are similarities to other non-point agricultural emissions like nitrogen that have been studied extensively, phosphorus is often characterized by the presence of large...

  1. Emission spectroscopy of argon ferrocene mixture jet in a low pressure plasma reactor

    International Nuclear Information System (INIS)

    Tiwari, N.; Tak, A.K.; Chakravarthy, Y.; Shukla, A.; Meher, K.C.; Ghorui, S.; Thiyagarajan, T.K.

    2015-01-01

    Emission spectroscopy is employed to measure the plasma temperature and species identification in a reactor used for studying homogenous nucleation and growth of iron nano particle. Reactor employs segmented non transferred plasma torch mounted on water cooled cylindrical chamber. The plasma jet passes through graphite nozzle and expands in low pressure reactor. Ferrocene is fed into the nozzle where it mixes with Argon plasma jet. A high resolution spectrograph (SHAMROCK 303i, resolution 0.06 nm) has been used to record the spectra over a wide range. Identification of different emission lines has been done using NIST database. Lines from (700 to 860nm) were considered for calculation of temperature. Spectra were recorded for different axial location, pressure and power. Temperature was calculated using Maxwell Boltzman plot method. Variation in temperature with pressure and location is presented and possible reasons for different behaviour are explored. (author)

  2. Brain Phosphorus Magnetic Resonance Spectroscopy Imaging of Sleep Homeostasis and Restoration in Drug Dependence

    Directory of Open Access Journals (Sweden)

    George H. Trksak

    2007-01-01

    Full Text Available Numerous reports have documented a high occurrence of sleep difficulties in drug-dependent populations, prompting researchers to characterize sleep profiles and physiology in drug abusing populations. This mini-review examines studies indicating that drug-dependent populations exhibit alterations in sleep homeostatic and restoration processes in response to sleep deprivation. Sleep deprivation is a principal sleep research tool that results in marked physiological challenge, which provides a means to examine sleep homeostatic processes in response to extended wakefulness. A report from our laboratory demonstrated that following recovery sleep from sleep deprivation, brain high-energy phosphates particularly beta–nucleoside triphosphate (beta-NTP are markedly increased as measured with phosphorus magnetic resonance spectroscopy (MRS. A more recent study examined the effects of sleep deprivation in opiate-dependent methadone-maintained (MM subjects. The study demonstrated increases in brain beta-NTP following recovery sleep. Interestingly, these increases were of a markedly greater magnitude in MM subjects compared to control subjects. A similar study examined sleep deprivation in cocaine-dependent subjects demonstrating that cocaine-dependent subjects exhibit greater increases in brain beta-NTP following recovery sleep when compared to control subjects. The studies suggest that sleep deprivation in both MM subjects and cocaine-dependent subjects is characterized by greater changes in brain ATP levels than control subjects. Greater enhancements in brain ATP following recovery sleep may reflect a greater disruption to or impact of sleep deprivation in drug dependent subjects, whereby sleep restoration processes may be unable to properly regulate brain ATP and maintain brain high-energy equilibrium. These studies support the notion of a greater susceptibility to sleep loss in drug dependent populations. Additional sleep studies in drug abusing

  3. Plasma emission spectroscopy of solids irradiated by intense XUV pulses from a free electron laser

    Czech Academy of Sciences Publication Activity Database

    Dzelzainis, T.W.J.; Chalupský, Jaromír; Fajardo, M.; Fäustlin, R.; Heimann, P.A.; Hájková, Věra; Juha, Libor; Jurek, Karel; Khattak, F.Y.; Kozlová, Michaela; Krzywinski, J.; Lee, R. W.; Nagler, B.; Nelson, A.J.; Rosmej, F.B.; Soberierski, R.; Toleikis, S.; Tschentscher, T.; Vinko, S.M.; Wark, J. S.; Whitcher, T.; Riley, D.

    2010-01-01

    Roč. 6, č. 1 (2010), 109-112 ISSN 1574-1818 R&D Projects: GA MŠk LC510; GA MŠk(CZ) LC528; GA MŠk LA08024; GA AV ČR IAAX00100903 Institutional research plan: CEZ:AV0Z10100523; CEZ:AV0Z10100521 Keywords : XUV emission spectroscopy * free-electron laser * warm dense matter Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.206, year: 2010

  4. Phosphorus in Agriculture : 100 % Zero

    NARCIS (Netherlands)

    Schnug, Ewald; De Kok, Luit J.

    2016-01-01

    Phosphorus is essential for all living organisms, reserves in geogenic deposits are finite, and phosphorus nutrient mining and oversupply are common phenomenons on agricultural soils. Only if the agricultural phosphorus cycle can be closed and the fertilized nutrient been utilized completely,

  5. Dual-array valence emission spectrometer (DAVES): A new approach for hard x-ray photon-in photon-out spectroscopies

    Energy Technology Data Exchange (ETDEWEB)

    Finkelstein, K. D., E-mail: kdf1@cornell.edu; Lyndaker, A.; Krawcyk, T.; Conrad, J. [CHESS Wilson Lab, Cornell University, Ithaca, NY 14853 (United States); Pollock, C. J. [Dept. of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)

    2016-07-27

    CHESS has developed and successfully deployed a novel Dual Array Valence Emission Spectrometer (DAVES) for high energy resolution, hard x-ray spectroscopy. DAVES employs the simplest method for scanning multiple spherical crystals along a Rowland Circle. The new design achieves unique 2-color collection capability and is built to take special advantage of pixel array detectors. Our initial results show why these detectors greatly improve data quality. The presentation emphasizes flexibility of experimental design offered by DAVES. Prospects and benefits of 2-color spectroscopy are illustrated and discussed.

  6. Chemical and structural effects of phosphorus on the corrosion behavior of ion beam mixed Fe-Cr-P alloys

    International Nuclear Information System (INIS)

    Demaree, J.D.; Was, G.S.; Sorensen, N.R.

    1992-01-01

    An experimental program was conducted to determine the mechanisms by which phosphorus affects the corrosion and passivation behavior of Fe-Cr-P alloys. To identify separately the effects of structure and chemistry on the corrosion behavior, thin films of Fe-10Cr-xP (0≤x≤35 at.%) were prepared by ion beam mixing. Films with a phosphorus content greater than approximately 20at.% were found to be entirely amorphous. Devitrification of the amorphous phase was accomplished by heating the samples to 450degC in an inert environment. Standard polarization tests of the sulfuric acid (with and without Cl - ) indicated that the films containing phosphorus were more corrosion resistant than Fe-10Cr, at both active and passive potentials. There was a monotonic relationship between the amount of phosphorus in the alloy and the corrosion resistance, with the open-circuit corrosion rate of Fe-10Cr-35P nearly four orders of magnitude lower than that of Fe-10Cr. Devitrification of the alloys had no significant effect on the corrosion rate, indicating that the primary effect of phosphorus is chemical in nature, and not structural. The passive oxides were depth-profiled using X-ray photoelectron spectroscopy, which indicated that phosphorus was a primary constituent, as phosphate. The presence of phosphate in the passive oxides reduced the overall corrosion rate directly, by suppressing anodic dissolution. The presence of phosphorus did enhance chromium enrichment in the oxide, but that was not thought to be the primary mechanism by which phosphorus increased the corrosion resistance. (orig.)

  7. Weak antilocalization effect in exfoliated black phosphorus revealed by temperature- and angle-dependent magnetoconductivity

    KAUST Repository

    Hou, Zhipeng; Gong, Chen; Wang, Yue; Zhang, Qiang; Yang, Bingchao; Zhang, Hongwei; Liu, Enke; Liu, Zhongyuan; Zeng, Zhongming; Wu, Guangheng; Wang, Wenhong; Zhang, Xixiang

    2018-01-01

    Recently, there have been increasingly debates on whether there exists a surface resonance state (SRS) in black phosphorus (BP), as suggested by recent angle-resolved photoemission spectroscopy (ARPES) results. To resolve this issue, we have performed temperature- and angle-dependent magnetoconductivity measurements on exfoliated, high-quality BP single crystals. A pronounced weak-antilocalization (WAL) effect was observed within a narrow temperature range of 8 - 16 K, with the electrical current flowing parallel to the cleaved ac-plane (along the a- or c-axis) and the magnetic field along the b-axis. The angle-dependent magnetoconductivity and the Hikami-Larkin-Nagaoka (HLN) model-fitted results have revealed that the observed WAL effect shows surface-bulk coherent features, which supports the existence of SRS in black phosphorus.

  8. Weak antilocalization effect in exfoliated black phosphorus revealed by temperature- and angle-dependent magnetoconductivity

    KAUST Repository

    Hou, Zhipeng

    2018-01-10

    Recently, there have been increasingly debates on whether there exists a surface resonance state (SRS) in black phosphorus (BP), as suggested by recent angle-resolved photoemission spectroscopy (ARPES) results. To resolve this issue, we have performed temperature- and angle-dependent magnetoconductivity measurements on exfoliated, high-quality BP single crystals. A pronounced weak-antilocalization (WAL) effect was observed within a narrow temperature range of 8 - 16 K, with the electrical current flowing parallel to the cleaved ac-plane (along the a- or c-axis) and the magnetic field along the b-axis. The angle-dependent magnetoconductivity and the Hikami-Larkin-Nagaoka (HLN) model-fitted results have revealed that the observed WAL effect shows surface-bulk coherent features, which supports the existence of SRS in black phosphorus.

  9. Phosphorus poisoning in waterfowl

    Science.gov (United States)

    Coburn, D.R.; DeWitt, J.B.; Derby, J.V.; Ediger, E.

    1950-01-01

    Black ducks and mallards were found to be highly susceptible to phosphorus poisoning. 3 mg. of white phosphorus per kg. of body weight given in a single dose resulted in death of a black duck in 6 hours. Pathologic changes in both acute and chronic poisoning were studied. Data are presented showing that diagnosis can be made accurately by chemical analysis of stored tissues in cases of phosphorus poisoning.

  10. High pressure chemistry of red phosphorus by photo-activated simple molecules

    Science.gov (United States)

    Ceppatelli, M.; Fanetti, S.; Bini, R.; Caporali, M.; Peruzzini, M.

    2014-05-01

    High pressure (HP) is very effective in reducing intermolecular distances and inducing unexpected chemical reactions. In addition the photo-activation of the reactants in HP conditions can lead to very efficient and selective processes. The chemistry of phosphorus is currently based on the white molecular form. The red polymeric allotrope, despite more stable and much less toxic, has not attracted much attention so far. However, switching from the white to the red form would benefit any industrial procedure, especially from an environmental point of view. On the other side, water and ethanol are renewable, environmental friendly and largely available molecules, usable as reactants and photo-activators in HP conditions. Here we report a study on the HP photo-induced reactivity of red phosphorus with water and ethanol, showing the possibility of very efficient and selective processes, leading to molecular hydrogen and valuable phosphorus compounds. The reactions have been studied by means of FTIR and Raman spectroscopy and pressure has been generated using membrane Diamond (DAC) and Sapphire (SAC) anvil cells. HP reactivity has been activated by the two-photon absorption of near-UV wavelengths and occurred in total absence of solvents, catalysts and radical initiators, at room T and mild pressure conditions (0.2-1.5 GPa).

  11. High pressure chemistry of red phosphorus by photo-activated simple molecules

    International Nuclear Information System (INIS)

    Ceppatelli, M; Bini, R; Caporali, M; Peruzzini, M; Fanetti, S

    2014-01-01

    High pressure (HP) is very effective in reducing intermolecular distances and inducing unexpected chemical reactions. In addition the photo-activation of the reactants in HP conditions can lead to very efficient and selective processes. The chemistry of phosphorus is currently based on the white molecular form. The red polymeric allotrope, despite more stable and much less toxic, has not attracted much attention so far. However, switching from the white to the red form would benefit any industrial procedure, especially from an environmental point of view. On the other side, water and ethanol are renewable, environmental friendly and largely available molecules, usable as reactants and photo-activators in HP conditions. Here we report a study on the HP photo-induced reactivity of red phosphorus with water and ethanol, showing the possibility of very efficient and selective processes, leading to molecular hydrogen and valuable phosphorus compounds. The reactions have been studied by means of FTIR and Raman spectroscopy and pressure has been generated using membrane Diamond (DAC) and Sapphire (SAC) anvil cells. HP reactivity has been activated by the two-photon absorption of near-UV wavelengths and occurred in total absence of solvents, catalysts and radical initiators, at room T and mild pressure conditions (0.2–1.5 GPa).

  12. Phosphorus oxide gate dielectric for black phosphorus field effect transistors

    Science.gov (United States)

    Dickerson, W.; Tayari, V.; Fakih, I.; Korinek, A.; Caporali, M.; Serrano-Ruiz, M.; Peruzzini, M.; Heun, S.; Botton, G. A.; Szkopek, T.

    2018-04-01

    The environmental stability of the layered semiconductor black phosphorus (bP) remains a challenge. Passivation of the bP surface with phosphorus oxide, POx, grown by a reactive ion etch with oxygen plasma is known to improve photoluminescence efficiency of exfoliated bP flakes. We apply phosphorus oxide passivation in the fabrication of bP field effect transistors using a gate stack consisting of a POx layer grown by reactive ion etching followed by atomic layer deposition of Al2O3. We observe room temperature top-gate mobilities of 115 cm2 V-1 s-1 in ambient conditions, which we attribute to the low defect density of the bP/POx interface.

  13. Vibrational emission analysis of the CN molecules in laser-induced breakdown spectroscopy of organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Fernández-Bravo, Ángel; Delgado, Tomás; Lucena, Patricia; Laserna, J. Javier, E-mail: laserna@uma.es

    2013-11-01

    Laser-induced breakdown spectroscopy (LIBS) of organic materials is based on the analysis of atomic and ionic emission lines and on a few molecular bands, the most important being the CN violet system and the C{sub 2} Swan system. This paper is focused in molecular emission of LIBS plasmas based on the CN (B{sup 2}Σ–X{sup 2}Σ) band, one of the strongest emissions appearing in all carbon materials when analyzed in air atmosphere. An analysis of this band with sufficient spectral resolution provides a great deal of information on the molecule, which has revealed that valuable information can be obtained from the plume chemistry and dynamics affecting the excitation mechanisms of the molecules. The vibrational emission of this molecular band has been investigated to establish the dependence of this emission on the molecular structure of the materials. The paper shows that excitation/emission phenomena of molecular species observed in the plume depend strongly on the time interval selected and on the irradiance deposited on the sample surface. Precise time resolved LIBS measurements are needed for the observation of distinctive CN emission. For the organic compounds studied, larger differences in the behavior of the vibrational emission occur at early stages after plasma ignition. Since molecular emission is generally more complex than that involving atomic emission, local plasma conditions as well as plume chemistry may induce changes in vibrational emission of molecules. As a consequence, alterations in the distribution of the emissions occur in terms of relative intensities, being sensitive to the molecular structure of every single material. - Highlights: • Vibrational emission of CN species in laser-induced plasmas has been investigated. • Distribution of vibrational emission of CN has been found to be time dependent. • Laser irradiance affects the vibrational distribution of the CN molecules. • Plume chemistry controls the excitation mechanisms of CN

  14. Sewage-effluent phosphorus: A greater risk to river eutrophication than agricultural phosphorus?

    International Nuclear Information System (INIS)

    Jarvie, Helen P.; Neal, Colin; Withers, Paul J.A.

    2006-01-01

    Phosphorus (P) concentrations from water quality monitoring at 54 UK river sites across seven major lowland catchment systems are examined in relation to eutrophication risk and to the relative importance of point and diffuse sources. The over-riding evidence indicates that point (effluent) rather than diffuse (agricultural) sources of phosphorus provide the most significant risk for river eutrophication, even in rural areas with high agricultural phosphorus losses. Traditionally, the relative importance of point and diffuse sources has been assessed from annual P flux budgets, which are often dominated by diffuse inputs in storm runoff from intensively managed agricultural land. However, the ecological risk associated with nuisance algal growth in rivers is largely linked to soluble reactive phosphorus (SRP) concentrations during times of ecological sensitivity (spring/summer low-flow periods), when biological activity is at its highest. The relationships between SRP and total phosphorus (TP; total dissolved P + suspended particulate P) concentrations within UK rivers are evaluated in relation to flow and boron (B; a tracer of sewage effluent). SRP is the dominant P fraction (average 67% of TP) in all of the rivers monitored, with higher percentages at low flows. In most of the rivers the highest SRP concentrations occur under low-flow conditions and SRP concentrations are diluted as flows increase, which is indicative of point, rather than diffuse, sources. Strong positive correlations between SRP and B (also TP and B) across all the 54 river monitoring sites also confirm the primary importance of point source controls of phosphorus concentrations in these rivers, particularly during spring and summer low flows, which are times of greatest eutrophication risk. Particulate phosphorus (PP) may form a significant proportion of the phosphorus load to rivers, particularly during winter storm events, but this is of questionable relevance for river eutrophication

  15. Effect of phosphorus sources on phosphorus and nitrogen utilization by three sweet potato cultivars

    International Nuclear Information System (INIS)

    Montanez, A.; Zapata, F.; Kumarasinghe, K.S.

    1996-01-01

    A greenhouse experiment was conducted at the FAO/IAEA Agriculture and Biotechnology Laboratory in Seibersdorf, Austria using three sweet potato cultivars, TIS 2, TIS 3053 and TIS 1487. The three sweet potato cultivars were grown at two levels of phosphorus (0 kg P/kg soil and 60 kg P/kg soil). The fertilizer treatments consisted of two sources of phosphorus, Gafza rock Phosphate and triple super phosphate with 14.19 and 19.76% total phosphorus, respectively. 15 N labelled urea was used to study the nitrogen recovery in tubers from the applied nitrogen fertilizer. The results from these preliminary studies indicate that there is considerable genotypic variation among cultivars in the efficiency with which phosphorus and nitrogen are taken up and used to produce biomass. Their response to different sources of phosphorus are also variable. TIS-2 and TIS-1487 have a greater ability to absorb phosphorus from Gafza rock phosphate and produce higher tube yields indicating their greater potential for using alternative sources of natural phosphate fertilizers more effectively. Gafza rock phosphate also increased accumulation of nitrogen in TIS-1487, a characteristic which will place this cultivar at an advantage when growing in soils low in nitrogen. On an overall basis taking into account tuber yield, phosphorus use efficiency, and nitrogen use efficiency, TIS-2 may be considered the better candidate for introduction into soils poor in resources particularly phosphorus. This study was conducted with a limited number of cultivars due to limitation in the availability of germplasma. In spite of this, the differences in their abilities for phosphorus and nitrogen uptake and use are clearly visible which justifies large scale screening experiments using a broader germplasm base, in the future. (author). 14 refs, 1 fig., 3 tabs

  16. Effect of phosphorus sources on phosphorus and nitrogen utilization by three sweet potato cultivars

    Energy Technology Data Exchange (ETDEWEB)

    Montanez, A; Zapata, F [FAO/IAEA Agriculture and Biotechnology Lab., Seibersdorf (Austria). Soils Science Unit; Kumarasinghe, K S [Joint FAO/IAEA Div. of Nuclear Techniques in Food and Agriculture, Vienna (Austria). Soil Fertility, Irrigation and Crop Production Section

    1996-07-01

    A greenhouse experiment was conducted at the FAO/IAEA Agriculture and Biotechnology Laboratory in Seibersdorf, Austria using three sweet potato cultivars, TIS 2, TIS 3053 and TIS 1487. The three sweet potato cultivars were grown at two levels of phosphorus (0 kg P/kg soil and 60 kg P/kg soil). The fertilizer treatments consisted of two sources of phosphorus, Gafza rock Phosphate and triple super phosphate with 14.19 and 19.76% total phosphorus, respectively. {sup 15}N labelled urea was used to study the nitrogen recovery in tubers from the applied nitrogen fertilizer. The results from these preliminary studies indicate that there is considerable genotypic variation among cultivars in the efficiency with which phosphorus and nitrogen are taken up and used to produce biomass. Their response to different sources of phosphorus are also variable. TIS-2 and TIS-1487 have a greater ability to absorb phosphorus from Gafza rock phosphate and produce higher tube yields indicating their greater potential for using alternative sources of natural phosphate fertilizers more effectively. Gafza rock phosphate also increased accumulation of nitrogen in TIS-1487, a characteristic which will place this cultivar at an advantage when growing in soils low in nitrogen. On an overall basis taking into account tuber yield, phosphorus use efficiency, and nitrogen use efficiency, TIS-2 may be considered the better candidate for introduction into soils poor in resources particularly phosphorus. This study was conducted with a limited number of cultivars due to limitation in the availability of germplasma. In spite of this, the differences in their abilities for phosphorus and nitrogen uptake and use are clearly visible which justifies large scale screening experiments using a broader germplasm base, in the future. (author). 14 refs, 1 fig., 3 tabs.

  17. Experimental evidence of six-fold oxygen coordination for phosphorus and XANES calculations

    Energy Technology Data Exchange (ETDEWEB)

    Flank, A-M; Trcera, N; Itie, J-P; Lagarde, P [Synchrotron Soleil, L' Orme des Merisiers, BP 48, 91192 Gif sur Yvette (France); Brunet, F [Laboratoire de Geologie, CNRS-ENS-UMR8538, 24 rue Lhommond, 75005 Paris (France); Irifune, T [Geodynamics Research Center, Ehime University, Matsuyama 790-8577 (Japan)

    2009-11-15

    Phosphorus, a group V element, has always been found so far in minerals, biological systems and synthetic compounds with an oxygen coordination number of four (i.e, PO{sub 4} groups). We demonstrate here using phosphorus K-edge XANES spectroscopy that this element can also adopt a six-fold oxygen coordination (i.e, PO{sub 6} groups). This new coordination was achieved in AlPO{sub 4} doped SiO{sub 2} stishovite synthesized at 18 GPa and 1873 K and quenched down to ambient conditions. The well-crystallized P-bearing stishovite grains (up to 100{mu}m diameter) were embedded in the back-transformation products of high pressure form of AlPO{sub 4} matrix. They were identified by elemental mapping ({mu}-XRF). {mu}-XANES spectra collected at the Si and P K edges in the Si rich region with a very low concentration of P present striking resemblance, Si itself being characteristic of pure stishovite. We can therefore infer that phosphorus in the corresponding stishovite crystal is involved in an octahedral coordination made of six oxygen atoms. First principle XANES calculations using a plane-wave density functional formalism with core-hole effects treated in a supercell approach at the P K edge for a P atom substituting an Si one in the stishovite structure confirm this assertion. This result shows that in the lower-mantle where all silicon is six-fold coordinated, phosphorus has the crystal-chemical ability to remain incorporated into silicate structures.

  18. Experimental evidence of six-fold oxygen coordination for phosphorus and XANES calculations

    Science.gov (United States)

    Flank, A.-M.; Trcera, N.; Brunet, F.; Itié, J.-P.; Irifune, T.; Lagarde, P.

    2009-11-01

    Phosphorus, a group V element, has always been found so far in minerals, biological systems and synthetic compounds with an oxygen coordination number of four (i.e, PO4 groups). We demonstrate here using phosphorus K-edge XANES spectroscopy that this element can also adopt a six-fold oxygen coordination (i.e, PO6 groups). This new coordination was achieved in AlPO4 doped SiO2 stishovite synthesized at 18 GPa and 1873 K and quenched down to ambient conditions. The well-crystallized P-bearing stishovite grains (up to 100μm diameter) were embedded in the back-transformation products of high pressure form of AlPO4 matrix. They were identified by elemental mapping (μ-XRF). μ-XANES spectra collected at the Si and P K edges in the Si rich region with a very low concentration of P present striking resemblance, Si itself being characteristic of pure stishovite. We can therefore infer that phosphorus in the corresponding stishovite crystal is involved in an octahedral coordination made of six oxygen atoms. First principle XANES calculations using a plane-wave density functional formalism with core-hole effects treated in a supercell approach at the P K edge for a P atom substituting an Si one in the stishovite structure confirm this assertion. This result shows that in the lower-mantle where all silicon is six-fold coordinated, phosphorus has the crystal-chemical ability to remain incorporated into silicate structures.

  19. Experimental evidence of six-fold oxygen coordination for phosphorus and XANES calculations

    International Nuclear Information System (INIS)

    Flank, A-M; Trcera, N; Itie, J-P; Lagarde, P; Brunet, F; Irifune, T

    2009-01-01

    Phosphorus, a group V element, has always been found so far in minerals, biological systems and synthetic compounds with an oxygen coordination number of four (i.e, PO 4 groups). We demonstrate here using phosphorus K-edge XANES spectroscopy that this element can also adopt a six-fold oxygen coordination (i.e, PO 6 groups). This new coordination was achieved in AlPO 4 doped SiO 2 stishovite synthesized at 18 GPa and 1873 K and quenched down to ambient conditions. The well-crystallized P-bearing stishovite grains (up to 100μm diameter) were embedded in the back-transformation products of high pressure form of AlPO 4 matrix. They were identified by elemental mapping (μ-XRF). μ-XANES spectra collected at the Si and P K edges in the Si rich region with a very low concentration of P present striking resemblance, Si itself being characteristic of pure stishovite. We can therefore infer that phosphorus in the corresponding stishovite crystal is involved in an octahedral coordination made of six oxygen atoms. First principle XANES calculations using a plane-wave density functional formalism with core-hole effects treated in a supercell approach at the P K edge for a P atom substituting an Si one in the stishovite structure confirm this assertion. This result shows that in the lower-mantle where all silicon is six-fold coordinated, phosphorus has the crystal-chemical ability to remain incorporated into silicate structures.

  20. SEQUENTIAL ELECTRODIALYTIC EXTRACTION OF PHOSPHORUS COMPOUNDS

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to an apparatus for electrodialytic extraction of phosphorus from a particulate material in suspension and to a method for electrodialytic phosphorus recovery, which uses the apparatus. The method may be applied for wastewater treatment, and/or treatment of particulate...... material rich in phosphorus. The present invention provides an apparatus for electrodialytic extraction of phosphorus from a particulate material comprising acidic and/or alkaline soluble phosphorus compounds, in suspension, comprising: • a first electrodialytic cell comprising a first anolyte compartment...

  1. PILCs for trapping phosphorus in a heavy duty engine exhaust system : An experimental evaluation of the phosphorus sorption capability of different clay materials

    OpenAIRE

    Kvarned, Anders

    2016-01-01

    In order to fulfil the requirements in the EURO VI standard, regulating emissions from heavy duty vehicles, the exhaust aftertreatment system needs to maintain its efficiency for at least seven years or 700 000 km. In diesel applications the diesel oxidation catalyst (DOC) is located closest to the engine and is thus the most vulnerable to poisoning contaminants, such as phosphorus originating from fuel and oil additives, which deactivates the catalyst. An idea to reduce the impact from phosp...

  2. Phosphorus containing sintered alloys (review)

    International Nuclear Information System (INIS)

    Muchnik, S.V.

    1984-01-01

    Phosphorus additives are considered for their effect on the properties of sintered alloys of different applications: structural, antifriction, friction, magnetic, hard, superhard, heavy etc. Data are presented on compositions and properties of phosphorus-containing materials produced by the powder metallurgy method. Phosphorus is shown to be an effective activator of sintering in some cases. When its concentration in the material is optimal it imparts the material such properties as strength, viscosity, hardness, wear resistance. Problems concerning powder metallurgy of amorphous phosphorus-containing alloys are reported

  3. Phosphorus and the dairy cow

    OpenAIRE

    Ekelund, Adrienne

    2003-01-01

    The general aim of the present work was to investigate phosphorus balance in the dairy cow, with reference to the amount and source of phosphorus. Furthermore, biochemical bone markers were used to study the bone turnover during the lactation and dry period. Phosphorus is located in every cell of the body and has more known functions than any other mineral element in the animal body. Phosphorus is also an important constituent of milk, and is therefore required in large amounts in a high yiel...

  4. Synergistic Effect of Nanosilica Aerogel with Phosphorus Flame Retardants on Improving Flame Retardancy and Leaching Resistance of Wood

    Directory of Open Access Journals (Sweden)

    Xiaodan Zhu

    2014-01-01

    Full Text Available Nanosilica (Nano-SiO2 sol fabricated by a sol-gel process was introduced into wood modification with phosphorus flame retardants to improve the flame retardancy and leaching resistance of wood. The obtained materials were characterized by scanning electron microscopy and energy dispersive spectrometer (SEM-EDS, thermogravimetric analysis (TGA, cone calorimetric (CONE, and infrared spectroscopy (FT-IR. The residual rate of flame retardants before and after leaching was determinated by a leaching resistance. The results showed that the phosphorus flame retardants and SiO2 sol could reside in the poplar wood and are widely distributed in the vessels, pits, wood timber, and the spaces between wood cells of poplar substrate. TGA and CONE results indicated that the introduction of nano-SiO2 aerogel with phosphorus flame retardants had a significantly synergistic effect on improving the flame retardancy and inhibiting the release of smoke and toxic gases. In addition, the leaching resistance test, combined with infrared analysis and EDS analysis, confirmed that the phosphorus flame retardants were able to be fixed by SiO2 aerogel in the wood.

  5. Optical Emission Spectroscopy of an Atmospheric Pressure Plasma Jet During Tooth Bleaching Gel Treatment.

    Science.gov (United States)

    Šantak, Vedran; Zaplotnik, Rok; Tarle, Zrinka; Milošević, Slobodan

    2015-11-01

    Optical emission spectroscopy was performed during atmospheric pressure plasma needle helium jet treatment of various tooth-bleaching gels. When the gel sample was inserted under the plasma plume, the intensity of all the spectral features increased approximately two times near the plasma needle tip and up to two orders of magnitude near the sample surface. The color change of the hydroxylapatite pastille treated with bleaching gels in conjunction with the atmospheric pressure plasma jet was found to be in correlation with the intensity of OH emission band (309 nm). Using argon as an additive to helium flow (2 L/min), a linear increase (up to four times) of OH intensity and, consequently, whitening (up to 10%) of the pastilles was achieved. An atmospheric pressure plasma jet activates bleaching gel, accelerates OH production, and accelerates tooth bleaching (up to six times faster).

  6. The nature of extreme emission line galaxies at z = 1-2: kinematics and metallicities from near-infrared spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Maseda, Michael V.; Van der Wel, Arjen; Rix, Hans-Walter; Da Cunha, Elisabete; Meidt, Sharon E. [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Pacifici, Camilla [Yonsei University Observatory, Yonsei University, Seoul 120-749 (Korea, Republic of); Momcheva, Ivelina; Van Dokkum, Pieter; Nelson, Erica J. [Department of Astronomy, Yale University, New Haven, CT 06520 (United States); Brammer, Gabriel B.; Ferguson, Henry C.; Koekemoer, Anton M. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Franx, Marijn; Fumagalli, Mattia [Leiden Observatory, Leiden University, Leiden (Netherlands); Bell, Eric F. [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States); Förster-Schreiber, Natascha M. [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany); Koo, David C. [UCO/Lick Observatory and Department of Astronomy and Astrophysics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Lundgren, Britt F. [Department of Astronomy, University of Wisconsin, 475 North Charter Street, Madison, WI 53706 (United States); Marchesini, Danilo [Physics and Astronomy Department, Tufts University, Robinson Hall, Room 257, Medford, MA 02155 (United States); Patel, Shannon G., E-mail: maseda@mpia.de [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); and others

    2014-08-10

    We present near-infrared spectroscopy of a sample of 22 Extreme Emission Line Galaxies at redshifts 1.3 < z < 2.3, confirming that these are low-mass (M{sub *} = 10{sup 8}-10{sup 9} M{sub ☉}) galaxies undergoing intense starburst episodes (M{sub *}/SFR ∼ 10-100 Myr). The sample is selected by [O III] or Hα emission line flux and equivalent width using near-infrared grism spectroscopy from the 3D-HST survey. High-resolution NIR spectroscopy is obtained with LBT/LUCI and VLT/X-SHOOTER. The [O III]/Hβ line ratio is high (≳ 5) and [N II]/Hα is always significantly below unity, which suggests a low gas-phase metallicity. We are able to determine gas-phase metallicities for seven of our objects using various strong-line methods, with values in the range 0.05-0.30 Z{sub ☉} and with a median of 0.15 Z{sub ☉}; for three of these objects we detect [O III] λ4363, which allows for a direct constraint on the metallicity. The velocity dispersion, as measured from the nebular emission lines, is typically ∼50 km s{sup –1}. Combined with the observed star-forming activity, the Jeans and Toomre stability criteria imply that the gas fraction must be large (f{sub gas} ≳ 2/3), consistent with the difference between our dynamical and stellar mass estimates. The implied gas depletion timescale (several hundred Myr) is substantially longer than the inferred mass-weighted ages (∼50 Myr), which further supports the emerging picture that most stars in low-mass galaxies form in short, intense bursts of star formation.

  7. Integral Field Spectroscopy of the Extended Emission-Line Region of 4C 37.43

    Science.gov (United States)

    Fu, Hai; Stockton, Alan

    2007-09-01

    We present Gemini integral field spectroscopy and Keck II long-slit spectroscopy of the extended emission-line region (EELR) around the quasar 4C 37.43. The velocity structure of the ionized gas is complex and cannot be explained globally by a simple dynamical model. The spectra from the clouds are inconsistent with shock or ``shock + precursor'' ionization models, but they are consistent with photoionization by the quasar nucleus. The best-fit photoionization model requires a low-metallicity [12+log(O/H)Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil), and CONICET (Argentina). Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the financial support of the W. M. Keck Foundation.

  8. Nuclear magnetic resonance spectroscopy of living systems : Applications in comparative physiology

    NARCIS (Netherlands)

    VanDenThillart, G; VanWaarde, A

    The most attractive feature of nuclear magnetic resonance spectroscopy (MRS) is the noninvasive and nondestructive measurement of chemical compounds in intact tissues. MRS already has many applications in comparative physiology, usually based on observation of P-31, since the levels of phosphorus

  9. Fertilizer phosphorus in some Finnish soils

    Directory of Open Access Journals (Sweden)

    Armi Kaila

    1961-01-01

    Full Text Available In the present paper it is tried to trace the fate of fertilizer phosphorus in soil by comparing the analyses of soils from treated and untreated plots of field trials. This indirect approach cannot be expected to provide exact values, but it is likely to give an approximate answer. The results reported above do not in any marked degree change our present conception of the forms in which fertilizer phosphorus accumulates in soils. In the acid soils studied (pH 4—6.4 in 0.02 N CaCl2 superphosphate tended to increase the fractions which were extracted by NH4F or NaOH. Hyperphosphate phosphorus was mostly found in the acid-soluble fraction. During a longer period of dressing with phosphate an increase in the organic phosphorus content of a peat soil could be detected. In the incubation experiments the mineralization of organic phosphorus occurred at a higher rate in the samples from the plots treated with superphosphate than in those from the untreated one. It might be supposed that the organic phosphorus mineralized mainly originated from the plant residues. It seems that the fractionation method developed by CHANG and JACKSON (4 for the estimation of discrete forms of soil phosphorus is not quite satisfactory for tracing the fertilizer phosphorus in soils recently dressed with phosphates. In particular, it may be fallacious to conclude that the fraction extracted by NH4F would only represent phosphorus bound to aluminium and its compounds. At least in the absence of soil, a large part of phosphorus in dicalcium phosphate dihydrate falls into this fraction, and also a small amount of hyperphosphate phosphorus may be found in it. The test values for »available» phosphorus showed the effect of fertilizers in accordance with previous observations (9, 13. Acetic acid soluble P revealed the treatment with hyperphosphate, but only slightly the application of superphosphate. The test value for the sorbed P of BRAY and KURTZ (2, or phosphorus

  10. Attaining 2D Black Phosphorus and Investigations into Floating-Electrode Dielectric Barrier Discharge Treatment of Solutions

    Science.gov (United States)

    Smith, Joshua Benjamin

    -ray diffraction, transmission electron microscopy, and Raman spectroscopy have confirmed successful growth of 2D black phosphorus from red phosphorus thin films for potential uses in 2D semiconductor applications. Additionally, this work discusses some of the chemistry occurring in solution as a result of nonthermal plasma treatment from a floating-electrode dielectric barrier discharge (FE-DBD) configuration. Nonthermal plasma generation allows for the treatment of heat sensitive materials. This has opened up the field to numerous clinical applications of nonthermal plasma treatment including sterilization and wound healing along with potentials in dentistry, dermatology, and even food industries. FE-DBD plasma treatment of water was found to provide a wide-range antimicrobial solution that remained active following 2 years of aging. This plasma-treated water was found to generate a number of ROS/RNS and the formation of these components was studied and verified with UV/Vis and ESR spectroscopy. Enhanced effects were observed when cell culture medium was plasma treated, suggesting the formation of additional reactive species from the plasma treatment of a variety of biomolecules. It is essential to understand these effects for a number of reasons. The possibility to generate a wide range of antimicrobial solutions from air, water, and basic biomolecules could provide a solution for those bacteria that have developed antibiotic resistances. Simultaneously, information into the reaction mechanisms of this FE-DBD plasma treatment can be investigated. All of the applications mentioned above involve complex networks of basic biomolecules, from skin tissue to bacteria cell walls. This work analyzes the effects of plasma treatment on several biomolecule solutions and simultaneously takes aim at understanding some of the potential mechanisms of plasma treatment. Studies were carried out using NMR and GC/MS. This information was used to investigate the possible targeted areas for FE

  11. Nanoscale Terahertz Emission Spectroscopy

    DEFF Research Database (Denmark)

    Pedersen, Pernille Klarskov; Kim, Hyewon; Colvin, Vicki L.

    By utilizing plasmonic coupling to an AFM probe, we demonstrate Laser Terahertz Emission Nanoscopy (LTEN) with sub-20 nm resolution. We demonstrate the resolution by imaging a single gold nanorod on an InAs substrate....

  12. Preparation of highly dispersed palladium–phosphorus nanoparticles and its electrocatalytic performance for formic acid electrooxidation

    International Nuclear Information System (INIS)

    Sun Hanjun; Xu Jiangfeng; Fu Gengtao; Mao Xinbiao; Zhang, Lu; Chen Yu; Zhou Yiming; Lu Tianhong; Tang Yawen

    2012-01-01

    Highly dispersed and ultrafine palladium–phosphorus (Pd–P) nanoparticles (NPs) are prepared with a novel phosphorus reduction method. The structural and electronic properties of Pd–P NPs are characterized using Fourier transform infrared (FT-IR), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The electrooxidation of formic acid on Pd–P NPs are investigated by using cyclic voltammetry, chronoamperometry and CO-stripping measurements. The physical characterizations indicate the doped P element can enhance the content of Pd 0 species in Pd NPs, decrease the particle size and improve the dispersion of Pd–P NPs. The electrochemical measurements show the Pd–P NPs have a better catalytic performance for formic acid electrooxidation than Pd NPs.

  13. Electron emission relevant to inner-shell photoionization of condensed water studied by multi-electron coincidence spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hikosaka, Y., E-mail: hikosaka@las.u-toyama.ac.jp [Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama 930-0194 (Japan); Mashiko, R.; Konosu, Y.; Soejima, K. [Department of Environmental Science, Niigata University, Niigata 950-2181 (Japan); Shigemasa, E. [UVSOR Facility, Institute for Molecular Science, Okazaki 444-8585 (Japan); SOKENDAI, Okazaki 444-8585 (Japan)

    2016-11-15

    Highlights: • Multi-electron coincidence spectroscopy is applied to the study of electron emissions from condensed H2O molecules. • Coincidence Auger spectra are obtained for different photoelectron energies. • The energy distribution of the slow electrons ejected in the Auger decay is deduced from three-fold coincidences. - Abstract: Multi-electron coincidence spectroscopy using a magnetic-bottle electron spectrometer has been applied to the study of the Auger decay following O1s photoionization of condensed H{sub 2}O molecules. Coincidence Auger spectra are obtained for three different photoelectron energy ranges. In addition, the energy distribution of the slow electrons ejected in the Auger decay of the O1s core hole is deduced from three-fold coincidences.

  14. Characterization by acoustic emission and electrochemical impedance spectroscopy of the cathodic disbonding of Zn coating

    International Nuclear Information System (INIS)

    Amami, Souhail; Lemaitre, Christian; Laksimi, Abdelouahed; Benmedakhene, Salim

    2010-01-01

    Galvanized steel has been tested in a synthetic sea water solution under different cathodic overprotection conditions. The generated hydrogen flux caused the damage of the metal-zinc interface and led to a progressive coating detachment. Scanning electron microscopy, electrochemical impedance spectroscopy and acoustic emission technique were used to characterize the damage chronology under different cathodic potentials. A damage mechanism was proposed and the acoustic signature related to the coating degradation was statistically identified using clustering techniques.

  15. Characterization by acoustic emission and electrochemical impedance spectroscopy of the cathodic disbonding of Zn coating

    Energy Technology Data Exchange (ETDEWEB)

    Amami, Souhail [Universite de Technologie de Compiegne, Departement de Genie Mecanique, Laboratoire Roberval, UMR 6066 du CNRS, B.P. 20529, 60206 Compiegne Cedex (France)], E-mail: souhail.amami@utc.fr; Lemaitre, Christian; Laksimi, Abdelouahed; Benmedakhene, Salim [Universite de Technologie de Compiegne, Departement de Genie Mecanique, Laboratoire Roberval, UMR 6066 du CNRS, B.P. 20529, 60206 Compiegne Cedex (France)

    2010-05-15

    Galvanized steel has been tested in a synthetic sea water solution under different cathodic overprotection conditions. The generated hydrogen flux caused the damage of the metal-zinc interface and led to a progressive coating detachment. Scanning electron microscopy, electrochemical impedance spectroscopy and acoustic emission technique were used to characterize the damage chronology under different cathodic potentials. A damage mechanism was proposed and the acoustic signature related to the coating degradation was statistically identified using clustering techniques.

  16. Phosphorus Regulation in Chronic Kidney Disease.

    Science.gov (United States)

    Suki, Wadi N; Moore, Linda W

    2016-01-01

    Serum phosphorus levels stay relatively constant through the influence of multiple factors-such as parathyroid hormone, fibroblast growth factor 23, and vitamin D-on the kidney, bone, and digestive system. Whereas normal serum phosphorus ranges between 3 mg/dL to 4.5 mg/dL, large cross-sectional studies have shown that even people with normal kidney function are sometimes found to have levels ranging between 1.6 mg/dL and 6.2 mg/dL. While this may partially be due to diet and the factors mentioned above, total understanding of these atypical ranges of serum phosphorus remains uncertain. Risks for bone disease are high in people aged 50 and older, and this group comprises a large proportion of people who also have chronic kidney disease. Consuming diets low in calcium and high in phosphorus, especially foods with phosphate additives, further exacerbates bone turnover. Existing bone disease increases the risk for high serum phosphorus, and higher serum phosphorus has been associated with increased adverse events and cardiovascular-related mortality both in people with chronic kidney disease and in those with no evidence of disease. Once kidney function has deteriorated to end-stage disease (Stage 5), maintaining normal serum phosphorus requires dietary restrictions, phosphate-binding medications, and dialysis. Even so, normal serum phosphorus remains elusive in many patients with Stage 5 kidney disease, and researchers are testing novel targets that may inhibit intestinal transport of phosphorus to achieve better phosphate control. Protecting and monitoring bone health should also aid in controlling serum phosphorus as kidney disease advances.

  17. [Study on Ammonia Emission Rules in a Dairy Feedlot Based on Laser Spectroscopy Detection Method].

    Science.gov (United States)

    He, Ying; Zhang, Yu-jun; You, Kun; Wang, Li-ming; Gao, Yan-wei; Xu, Jin-feng; Gao, Zhi-ling; Ma, Wen-qi

    2016-03-01

    It needs on-line monitoring of ammonia concentration on dairy feedlot to disclose ammonia emissions characteristics accurately for reducing ammonia emissions and improving the ecological environment. The on-line monitoring system for ammonia concentration has been designed based on Tunable Diode Laser Absorption Spectroscopy (TDLAS) technology combining with long open-path technology, then the study has been carried out with inverse dispersion technique and the system. The ammonia concentration in-situ has been detected and ammonia emission rules have been analyzed on a dairy feedlot in Baoding in autumn and winter of 2013. The monitoring indicated that the peak of ammonia concentration was 6.11 x 10(-6) in autumn, and that was 6.56 x 10(-6) in winter. The concentration results show that the variation of ammonia concentration had an obvious diurnal periodicity, and the general characteristic of diurnal variation was that the concentration was low in the daytime and was high at night. The ammonia emissions characteristic was obtained with inverse dispersion model that the peak of ammonia emissions velocity appeared at noon. The emission velocity was from 1.48 kg/head/hr to 130.6 kg/head/hr in autumn, and it was from 0.004 5 kg/head/hr to 43.32 kg/head/hr in winter which was lower than that in autumn. The results demonstrated ammonia emissions had certain seasonal differences in dairy feedlot scale. In conclusion, the ammonia concentration was detected with optical technology, and the ammonia emissions results were acquired by inverse dispersion model analysis with large range, high sensitivity, quick response without gas sampling. Thus, it's an effective method for ammonia emissions monitoring in dairy feedlot that provides technical support for scientific breeding.

  18. Imaging buried organic islands by spatially resolved ballistic electron emission spectroscopy

    International Nuclear Information System (INIS)

    Goh, Kuan Eng J; Bannani, A; Troadec, C

    2008-01-01

    The well-known Au/n-Si(111) Schottky interface is modified by a discontinuous pentacene film (∼1.5 nm thick) and studied using spatially resolved ballistic electron emission spectroscopy (BEES). The pentacene film introduced subtle changes to the interface which cannot be definitively detected by current-voltage measurements or a standard BEES analysis of the barrier height. In contrast, analyzing the BEES results in a dual-parameter (transmission attenuation and barrier height) space allows the effect of the pentacene film on the Au/n-Si(111) interface to be clearly demonstrated. We found that the pentacene film behaves like a tunneling barrier and increases the distribution of local barrier heights with a tendency toward lower values. Our results highlight the potential of the dual-parameter BEES analysis for understanding local interface modification by molecules.

  19. Observing Solvation Dynamics with Simultaneous Femtosecond X-ray Emission Spectroscopy and X-ray Scattering

    DEFF Research Database (Denmark)

    Haldrup, Kristoffer; Gawelda, Wojciech; Abela, Rafael

    2016-01-01

    and structural changes, and local solvent structural changes are desired. We have studied the intra- and intermolecular dynamics of a model chromophore, aqueous [Fe(bpy)3]2+, with complementary X-ray tools in a single experiment exploiting intense XFEL radiation as a probe. We monitored the ultrafast structural...... rearrangement of the solute with X-ray emission spectroscopy, thus establishing time zero for the ensuing X-ray diffuse scattering analysis. The simultaneously recorded X-ray diffuse scattering atterns reveal slower subpicosecond dynamics triggered by the intramolecular structural dynamics of the photoexcited...

  20. Forms and lability of phosphorus in algae and aquatic macrophytes characterized by solution 31P NMR coupled with enzymatic hydrolysis

    Science.gov (United States)

    Increased information on forms and lability of phosphorus (P) in aquatic macrophytes and algae is crucial for better understanding of P biogeochemical cycling in eutrophic lakes. In this work, solution 31P nuclear magnetic resonance (NMR) spectroscopy coupled with enzymatic hydrolysis (EH) was used ...

  1. Interaction of phosphorus pentachloride with trichlorides of metals of the second half of lanthanide series and scandium subgroup

    International Nuclear Information System (INIS)

    Salyulev, A.B.; Vovkotrub, Eh.G.; Strekalovskij, V.N.

    1999-01-01

    With the use of Raman laser spectroscopy a study is made into interactions of molten TbCl 3 , ErCl 3 , YbCl 3 , YCl 3 and ScCl 3 with phosphorus pentachloride vapors at elevated pressure (up to 30-35 atm) as well as solid REM trichlorides with molten PCl 5 . It is revealed for first time that the interaction can be accompanied by reactions resulting in formation of complex chloride cations [PCl 4 ] + and anions [MCl 6 ] 3- of trivalent metals. The prediction is made about the possibility of chemical interaction of phosphorus pentachloride with trichlorides of all yttrium subgroup lanthanides under similar conditions

  2. Analytical applications of atomic spectroscopy, with particular reference to inductively coupled plasma emission analysis of coal and fly ash

    International Nuclear Information System (INIS)

    Pougnet, M.A.B.

    1983-08-01

    This thesis outlines the analytical applications of atomic emission and absorption spectroscopy to a variety of materials. Special attention was directed to the analysis of coal and coal ashes. A simple slurry sampling technique was developed and used to determine V, Ni, Co, Mo and Mn in the National Bureau of Standards Standard Reference Materials (NBS-SRM) coals 1632a and 1635 by furnace atomic absorption spectroscopy (FAAS). Coal and fly ash were analysed by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The determination of B, Be, Li, C, K and other trace elements by ICP-AES was investigated. Analytical methods were developed for the analysis of coal, fly ash and water samples. Fusion with sodium carbonate and a digestion bomb dissolution method were compared for the determination of boron in a South African boron-rich mineral (Kornerupine). Eight elements were determined in 10 industrial water samples from a power plant. Ca, Mg, Si and B were determined by ICP-AES and V, Ni, Co and Mo by FAAS. Various problems encountered during the course of the work and interferences in ICP-AES analysis are discussed. Some recommendations concerning method development and routine analysis by this technique are suggested

  3. Plasma control using neural network and optical emission spectroscopy

    International Nuclear Information System (INIS)

    Kim, Byungwhan; Bae, Jung Ki; Hong, Wan-Shick

    2005-01-01

    Due to high sensitivity to process parameters, plasma processes should be tightly controlled. For plasma control, a predictive model was constructed using a neural network and optical emission spectroscopy (OES). Principal component analysis (PCA) was used to reduce OES dimensionality. This approach was applied to an oxide plasma etching conducted in a CHF 3 /CF 4 magnetically enhanced reactive ion plasma. The etch process was systematically characterized by means of a statistical experimental design. Three etch outputs (etch rate, profile angle, and etch rate nonuniformity) were modeled using three different approaches, including conventional, OES, and PCA-OES models. For all etch outputs, OES models demonstrated improved predictions over the conventional or PCA-OES models. Compared to conventional models, OES models yielded an improvement of more than 25% in modeling profile angle and etch rate nonuniformtiy. More than 40% improvement over PCA-OES model was achieved in modeling etch rate and profile angle. These results demonstrate that nonreduced in situ data are more beneficial than reduced one in constructing plasma control model

  4. Phosphorus and Nutrition in Chronic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Emilio González-Parra

    2012-01-01

    Full Text Available Patients with renal impairment progressively lose the ability to excrete phosphorus. Decreased glomerular filtration of phosphorus is initially compensated by decreased tubular reabsorption, regulated by PTH and FGF23, maintaining normal serum phosphorus concentrations. There is a close relationship between protein and phosphorus intake. In chronic renal disease, a low dietary protein content slows the progression of kidney disease, especially in patients with proteinuria and decreases the supply of phosphorus, which has been directly related with progression of kidney disease and with patient survival. However, not all animal proteins and vegetables have the same proportion of phosphorus in their composition. Adequate labeling of food requires showing the phosphorus-to-protein ratio. The diet in patients with advanced-stage CKD has been controversial, because a diet with too low protein content can favor malnutrition and increase morbidity and mortality. Phosphorus binders lower serum phosphorus and also FGF23 levels, without decreasing diet protein content. But the interaction between intestinal dysbacteriosis in dialysis patients, phosphate binder efficacy, and patient tolerance to the binder could reduce their efficiency.

  5. The location and nature of accumulated phosphorus in seven sludges from activated sludge plants which exhibited enhanced phosphorus removal

    International Nuclear Information System (INIS)

    Buchan, L.

    1981-01-01

    Electron microscopy combined with the energy dispersive analysis of X-rays (EDX) has been used to examine the nature of the phosphorus accumulated in sludges from seven activated sludge plants exhibiting enhanced phosphorus removal. Large phosphorus accumulations were located in identical structures in the sludges examined. The phosphorus was located in large electron-dense bodies, within large bacterial cells which were characteristically grouped in clusters. The calcium:phosphorus ratio of these electron-dense bodies precluded them from being any form of calcium phosphate precipitate. Quantitative analysis indicated that the electron-dense bodies contained in excess of 30% phosphorus. The results obtained are supportive of a biological mechanism of enhanced phosphorus uptake in activated sludge

  6. Phosphorus vacancy cluster model for phosphorus diffusion gettering of metals in Si

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Renyu; Trzynadlowski, Bart; Dunham, Scott T. [Department of Electrical Engineering, University of Washington, Seattle, Washington 98195 (United States)

    2014-02-07

    In this work, we develop models for the gettering of metals in silicon by high phosphorus concentration. We first performed ab initio calculations to determine favorable configurations of complexes involving phosphorus and transition metals (Fe, Cu, Cr, Ni, Ti, Mo, and W). Our ab initio calculations found that the P{sub 4}V cluster, a vacancy surrounded by 4 nearest-neighbor phosphorus atoms, which is the most favorable inactive P species in heavily doped Si, strongly binds metals such as Cu, Cr, Ni, and Fe. Based on the calculated binding energies, we build continuum models to describe the P deactivation and Fe gettering processes with model parameters calibrated against experimental data. In contrast to previous models assuming metal-P{sub 1}V or metal-P{sub 2}V as the gettered species, the binding of metals to P{sub 4}V satisfactorily explains the experimentally observed strong gettering behavior at high phosphorus concentrations.

  7. Peak Phosphorus: Clarifying the Key Issues of a Vigorous Debate about Long-Term Phosphorus Security

    Directory of Open Access Journals (Sweden)

    Stuart White

    2011-10-01

    Full Text Available This paper reviews the latest information and perspectives on global phosphorus scarcity. Phosphorus is essential for food production and modern agriculture currently sources phosphorus fertilizers from finite phosphate rock. The 2008 food and phosphate fertilizer price spikes triggered increased concerns regarding the depletion timeline of phosphate rock reserves. While estimates range from 30 to 300 years and are shrouded by lack of publicly available data and substantial uncertainty, there is a general consensus that the quality and accessibility of remaining reserves are decreasing and costs will increase. This paper clarifies common sources of misunderstandings about phosphorus scarcity and identifies areas of consensus. It then asks, despite some persistent uncertainty, what would it take to achieve global phosphorus security? What would a ‘hard-landing’ response look like and how could preferred ‘soft-landing’ responses be achieved?

  8. Emission spectrochemical analysis

    International Nuclear Information System (INIS)

    Rives, R.D.; Bruks, R.R.

    1983-01-01

    The emission spectrochemical method of analysis based on the fact that atoms of elements can be excited in the electric arc or in the laser beam and will emit radiation with characteristic wave lengths is considered. The review contains the data on spectrochemical analysis, of liquids geological materials, scheme of laser microprobe. The main characteristics of emission spectroscopy, atomic absorption spectroscopy and X-ray fluorescent analysis, are aeneralized

  9. Phosphorus-31 and proton magnetic resonance spectroscopy of the medial temporal region in schizophrenic patients

    International Nuclear Information System (INIS)

    Yamada, Koichiro

    1996-01-01

    Phosphorus-31 magnetic resonance spectroscopy (MRS) was performed 22 schizophrenic patients and in 22 healthy volunteers. Psychiatric symptoms were estimated on the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Negative Symptoms (SANS) and the Scale for the Assessment of Positive Symptoms (SAPS). The spectra were quantified for phosphomonoesters (PME), inorganic orthophosphate (Pi), phosphodiesters (PDE), phosphocreatine (Pcr) and the γ, α and β phosphates of 5'-adenosine triphosphate (ATP) by peak area measurements. Proton MRS was performed in 15 schizophrenic patients and in 15 healthy volunteers. Psychiatric symptoms were estimated on the Positive and Negative Syndrome Scale (PANSS) and the SANS. The spectra of N-acetylates (NA), choline-containing compounds (Cho) and creatine-phosphocreatine (Cr) were quantified. The patients showed an increase in the % PDE and a decrease in the % β-ATP in the left temporal region. Positive correlations were found between the % PDE and the subscale of positive symptoms on the BPRS and the total score of SAPS. The % β-ATP correlated negatively with the total score on SAPS. The NA/Cho and NA/Cr ratios were significantly lower in patients than in normal subjects. The Cho/Cr ratio was higher in the patient group. The age at onset of illness correlated positively with the NA/Cho and NA/Cr ratios. No significant correlations were observed between the ratios of metabolites and the scores of PANSS and SANS. There were no significant associations between the mole percentages and the ratios and the daily doses of neuroleptics and anticholinergics. These findings suggest that the disturbed membrane phospholipid and high-energy phosphate metabolism in the left medial temporal region may be one of the pathophysiologies of neuroleptic-resistant positive symptoms in schizophrenia and these abnormalities may be related to neuronal loss and/or neuronal dysfunction in this region. (H.O.)

  10. Revisiting the electrochemical impedance spectroscopy of magnesium with online inductively coupled plasma atomic emission spectroscopy.

    Science.gov (United States)

    Shkirskiy, Viacheslav; King, Andrew D; Gharbi, Oumaïma; Volovitch, Polina; Scully, John R; Ogle, Kevin; Birbilis, Nick

    2015-02-23

    The electrochemical impedance of reactive metals such as magnesium is often complicated by an obvious inductive loop with decreasing frequency of the AC polarising signal. The characterisation and ensuing explanation of this phenomenon has been lacking in the literature to date, being either ignored or speculated. Herein, we couple electrochemical impedance spectroscopy (EIS) with online atomic emission spectroelectrochemistry (AESEC) to simultaneously measure Mg-ion concentration and electrochemical impedance spectra during Mg corrosion, in real time. It is revealed that Mg dissolution occurs via Mg(2+) , and that corrosion is activated, as measured by AC frequencies less than approximately 1 Hz approaching DC conditions. The result of this is a higher rate of Mg(2+) dissolution, as the voltage excitation becomes slow enough to enable all Mg(2+) -enabling processes to adjust in real time. The manifestation of this in EIS data is an inductive loop. The rationalisation of such EIS behaviour, as it relates to Mg, is revealed for the first time by using concurrent AESEC. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Phosphorus Speciation of Forest-soil Organic Surface Layers using P K-edge XANES Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    J Prietzel; J Thieme; D Paterson

    2011-12-31

    The phosphorus (P) speciation of organic surface layers from two adjacent German forest soils with different degree of water-logging (Stagnosol, Rheic Histosol) was analyzed by P K-edge XANES and subsequent Linear Combination Fitting. In both soils, {approx}70% of the P was inorganic phosphate and {approx}30% organic phosphate; reduced P forms such as phosphonate were absent. The increased degree of water-logging in the Histosol compared to the Stagnosol did not affect P speciation.

  12. Fluorescence excitation-emission matrix spectroscopy of vitiligo skin in vivo (Conference Presentation)

    Science.gov (United States)

    Zhao, Jianhua; Richer, Vincent; Al Jasser, Mohammed; Zandi, Soodabeh; Kollias, Nikiforos; Kalia, Sunil; Zeng, Haishan; Lui, Harvey

    2016-02-01

    Fluorescence signals depend on the intensity of the exciting light, the absorption properties of the constituent molecules, and the efficiency with which the absorbed photons are converted to fluorescence emission. The optical features and appearance of vitiligo have been explained primarily on the basis of reduced epidermal pigmentation, which results in abnormal white patches on the skin. The objective of this study is to explore the fluorescence properties of vitiligo and its adjacent normal skin using fluorescence excitation-emission matrix (EEM) spectroscopy. Thirty five (35) volunteers with vitiligo were acquired using a double-grating spectrofluorometer with excitation and emission wavelengths of 260-450 nm and 300-700 nm respectively. As expected, the most pronounced difference between the spectra obtained from vitiligo lesions compared to normally pigmented skin was that the overall fluorescence was much higher in vitiligo; these differences increased at shorter wavelengths, thus matching the characteristic spectral absorption of epidermal melanin. When comparing the fluorescence spectra from vitiligo to normal skin we detected three distinct spectral bands centered at 280nm, 310nm, and 335nm. The 280nm band may possibly be related to inflammation, whereas the 335 nm band may arise from collagen or keratin cross links. The source of the 310 nm band is uncertain; it is interesting to note its proximity to the 311 nm UV lamps used for vitiligo phototherapy. These differences are accounted for not only by changes in epidermal pigment content, but also by other optically active cutaneous biomolecules.

  13. X-ray spectral determination of chemical state of phosphorus and sulfur in anodic oxide films on niobium

    International Nuclear Information System (INIS)

    Bokij, L.P.; Kostikov, Yu.P.

    1989-01-01

    Chemical forms of phosphorus and sulfur in niobium oxide anodic film, obtained by electrochemical technique using niobium in H 2 SO 4 and H 3 PO 4 aqueous solutions, are determined using data on chemical shifts of X-ray emission lines. Films represent Nb 2 O 5(1-γ) (SO 4 ) 5γ and Nb 2 O 5(1-γ) (PO 4 ) 10γ/3 (γ -share of oxygen substituted by acid anion) composition oxosalts. Electrolyte role in formation of niobium anodic oxide structure and effect of phosphorus and sulfur compounds on anodic film conductivity are determined

  14. The reproducibility of 31-phosphorus MRS measures of muscle energetics at 3 Tesla in trained men.

    Directory of Open Access Journals (Sweden)

    Lindsay M Edwards

    Full Text Available OBJECTIVE: Magnetic resonance spectroscopy (MRS provides an exceptional opportunity for the study of in vivo metabolism. MRS is widely used to measure phosphorus metabolites in trained muscle, although there are no published data regarding its reproducibility in this specialized cohort. Thus, the aim of this study was to assess the reproducibility of (31P-MRS in trained skeletal muscle. METHODS: We recruited fifteen trained men (VO(2peak = 4.7±0.8 L min(-1/58±8 mL kg(-1 min(-1 and performed duplicate MR experiments during plantar flexion exercise, three weeks apart. RESULTS: Measures of resting phosphorus metabolites were reproducible, with 1.7 mM the smallest detectable difference in phosphocreatine (PCr. Measures of metabolites during exercise were less reliable: exercising PCr had a coefficient of variation (CV of 27% during exercise, compared with 8% at rest. Estimates of mitochondrial function were variable, but experimentally useful. The CV of PCr(1/2t was 40%, yet much of this variance was inter-subject such that differences of <20% were detectable with n = 15, given a significance threshold of p<0.05. CONCLUSIONS: 31-phosphorus MRS provides reproducible and experimentally useful measures of phosphorus metabolites and mitochondrial function in trained human skeletal muscle.

  15. Estimation of phosphorus flux in rivers during flooding.

    Science.gov (United States)

    Chen, Yen-Chang; Liu, Jih-Hung; Kuo, Jan-Tai; Lin, Cheng-Fang

    2013-07-01

    Reservoirs in Taiwan are inundated with nutrients that result in algal growth, and thus also reservoir eutrophication. Controlling the phosphorus load has always been the most crucial issue for maintaining reservoir water quality. Numerous agricultural activities, especially the production of tea in riparian areas, are conducted in watersheds in Taiwan. Nutrients from such activities, including phosphorus, are typically flushed into rivers during flooding, when over 90% of the yearly total amount of phosphorous enters reservoirs. Excessive or enhanced soil erosion from rainstorms can dramatically increase the river sediment load and the amount of particulate phosphorus flushed into rivers. When flow rates are high, particulate phosphorus is the dominant form of phosphorus, but sediment and discharge measurements are difficult during flooding, which makes estimating phosphorus flux in rivers difficult. This study determines total amounts of phosphorus transport by measuring flood discharge and phosphorous levels during flooding. Changes in particulate phosphorus, dissolved phosphorus, and their adsorption behavior during a 24-h period are analyzed owing to the fact that the time for particulate phosphorus adsorption and desorption approaching equilibrium is about 16 h. Erosion of the reservoir watershed was caused by adsorption and desorption of suspended solids in the river, a process which can be summarily described using the Lagmuir isotherm. A method for estimating the phosphorus flux in the Daiyujay Creek during Typhoon Bilis in 2006 is presented in this study. Both sediment and phosphorus are affected by the drastic discharge during flooding. Water quality data were collected during two flood events, flood in June 9, 2006 and Typhoon Bilis, to show the concentrations of suspended solids and total phosphorus during floods are much higher than normal stages. Therefore, the drastic changes of total phosphorus, particulate phosphorus, and dissolved phosphorus in

  16. Total phosphorus, phytate phosphorus contents and the correlation of phytates with amylose in selected edible beans in Sri Lanka

    Directory of Open Access Journals (Sweden)

    Keerthana Sivakumaran

    2018-02-01

    Full Text Available Phytate a major anti nutritional factors in legumes and it accounts for larger portion of the total phosphorus, while limiting the bioavailablity of certain divalent cations to the human body. Legumes of eleven varieties cultivated in Sri Lanka, Mung bean (MI5, MI6, Cowpea (Waruni, MICP1, Bombay, Dhawala, ANKCP1, Soybean (MISB1, Pb1 and Horse gram (ANKBlack, ANKBrown were analyzed for phosphorus content and phytate content. Total phosphorus content was quantified by dry ashing followed by spectrophotometrical measurement of the blue colour intensity of acid soluble phosphate with sodium molybdate in the presence of ascorbic acid while phytate phosphorus using anion exchange chromatographic technique followed by spectrometrical measurement of the digested organic phosphorus and amylose content by Simple Iodine-Colourimetric method. Where the least value for phosphorus was observed 275.04 ±1.44 mg.100g-1 in ANKBlack (Horse gram and the highest in MISB1 (Soyabean with 654.94 ±0.05 mg.100g-1. The phytate phosphorus content (which is a ratio of phyate to total phosphorus was highest in Dhawala (Cowpea. The phytate phosphorus (which is a ratio of phyate to total phosphorus was highest in Dhawala with 67.42% and least in Bombay (Cowpea with 24.87%. The amylose content of the legumes was least in Pb1 with 8.71 ±0.13 mg.100mg-1 and the highest in MI6 22.58 ±0.71 mg.100mg-1. The correlation between phyate and total phosphorus was significant (p <0.05 and positive (r = 0.62. Similarly the correlation coefficient for phytate phosphorus and total phosphorus was significant (p <0.05 and positive (r = 0.63. Amylose content of legumes was significantly correlated negatively (p <0.05 with the total phytates content (r = -0.82.

  17. Potential Phosphorus Mobilisation in Peat Soils

    DEFF Research Database (Denmark)

    Forsmann, Ditte M.; Kjærgaard, Charlotte

    2012-01-01

    Re-establishment of wetlands on peat soils containing phosphorus bound to iron(III)-oxides can lead to an undesirable phosphorus loss to the aquatic environment due to the reductive dissolution of iron(III)-oxides. Thus it is important to be able to assess the potential phosphorus mobilisation from...... peat soils before a re-establishment takes place. The potential phosphorus mobilisation from a peat soil depends not only on the geochemical characteristics but also on the redox conditions, the hydrological regime in the area as well as the hydro-physical properties of the soil. The hypothesis...... for this study is (i) the release of phosphorus in peat is controlled by the geochemistry; (ii) the mobilisation of phosphorus is controlled by both geochemistry and hydro-physics of the soil. For this study, 10 Danish riparian lowland areas with peat soil were selected based on their geochemical characteristics...

  18. Study of the effective inverse photon efficiency using optical emission spectroscopy combined with cavity ring-down spectroscopy approach

    Science.gov (United States)

    Wu, Xingwei; Li, Cong; Wang, Yong; Wang, Zhiwei; Feng, Chunlei; Ding, Hongbin

    2015-09-01

    The hydrocarbon impurities formation is inevitable due to wall erosion in a long pulse high performance scenario with carbon-based plasma facing materials in fusion devices. The standard procedure to determine the chemical erosion yield in situ is by means of inverse photon efficiency D/XB. In this work, the conversion factor between CH4 flux and photon flux of CH A → X transition (effective inverse photon efficiency PE-1) was measured directly using a cascaded arc plasma simulator with argon/methane. This study shows that the measured PE-1 is different from the calculated D/XB. We compared the photon flux measured by optical emission spectroscopy (OES) and calculated by electron impact excitation of CH(X) which was diagnosed by cavity ring-down spectroscopy (CRDS). It seems that charge exchange and dissociative recombination processes are the main channels of CH(A) production and removal which lead to the inconsistency of PE -1 and D/XB at lower temperature. Meanwhile, the fraction of excited CH(A) produced by dissociative recombination processes was investigated, and we found it increased with Te in the range from 4% to 13% at Te definition instead of D/XB since the electron impact excitation is not the only channel of CH(A) production. These results have an effect on evaluating the yield of chemical erosion in divertor of fusion device.

  19. Assessing the Long Term Impact of Phosphorus Fertilization on Phosphorus Loadings Using AnnAGNPS

    OpenAIRE

    Yuan, Yongping; Bingner, Ronald L.; Locke, Martin A.; Stafford, Jim; Theurer, Fred D.

    2011-01-01

    High phosphorus (P) loss from agricultural fields has been an environmental concern because of potential water quality problems in streams and lakes. To better understand the process of P loss and evaluate the effects of different phosphorus fertilization rates on phosphorus losses, the USDA Annualized AGricultural Non-Point Source (AnnAGNPS) pollutant loading model was applied to the Ohio Upper Auglaize watershed, located in the southern portion of the Maumee River Basin. In this study, the ...

  20. Layered Black Phosphorus as a Selective Vapor Sensor.

    Science.gov (United States)

    Mayorga-Martinez, Carmen C; Sofer, Zdeněk; Pumera, Martin

    2015-11-23

    Black phosphorus is a layered material that is sensitive to the surrounding atmosphere. This is generally considered as a disadvantage, especially when compared to more stable layered compounds, such as graphite or MoS2. This sensitivity is now turned into an advantage. A vapor sensor that is based on layered black phosphorus and uses electrochemical impedance spectroscopy as the detection method is presented; the device selectively detects methanol vapor. The impedance phase measured at a constant frequency is used as a distinctive parameter for the selective quantification of methanol, and increases with the methanol concentration. The low detection limit of 28 ppm is well below the approved exposure limit of 200 ppm. The results are highly reproducible, and the vapor sensor is shown to be very selective in the presence of other vapors and to have long-term stability. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

  1. Complex Molecules in the Laboratory - a Comparison of Chriped Pulse and Emission Spectroscopy

    Science.gov (United States)

    Hermanns, Marius; Wehres, Nadine; Maßen, Jakob; Schlemmer, Stephan

    2017-06-01

    Detecting molecules of astrophysical interest in the interstellar medium strongly relies on precise spectroscopic data from the laboratory. In recent years, the advancement of the chirped-pulse technique has added many more options available to choose from. The Cologne emission spectrometer is an additional path to molecular spectroscopy. It allows to record instantaneously broad band spectra with calibrated intensities. Here we present a comparison of both methods: The Cologne chirped-pulse spectrometer as well as the Cologne emission spectrometer both cover the frequency range of 75-110 GHz, consistent with the ALMA Band 3 receivers. High sensitive heterodyne receivers with very low noise temperature amplifiers are used with a typical bandwidth of 2.5 GHz in a single sideband. Additionally the chirped-pulse spectrometer contains a high power amplifier of 200 mW for the excitation of molecules. Room temperature spectra of methyl cyanide and comparison of key features, such as measurement time, sensitivity, limitations and commonalities are shown in respect to identification of complex molecules of astrophysical importance. In addition, future developments for both setups will be discussed.

  2. Phosphorus dendrimers for nanomedicine.

    Science.gov (United States)

    Caminade, Anne-Marie

    2017-08-31

    From biomaterials to imaging, and from drug delivery to drugs by themselves, phosphorus-containing dendrimers offer a large palette of biological properties, depending essentially on their types of terminal functions. The most salient examples of phosphorus dendrimers used for the elaboration of bio-chips and of supports for cell cultures, for imaging biological events, and for carrying and delivering drugs or biomacromolecules are presented in this feature article. Several phosphorus dendrimers can be considered also as drugs per se (by themselves) in particular to fight against cancers, neurodegenerative diseases, and inflammation, both in vitro and in vivo. Toxicity assays are also reported.

  3. Effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus application rates

    Directory of Open Access Journals (Sweden)

    S. Fatih Ergin

    2016-10-01

    Full Text Available In this study, effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus fertilization rates were investigated. Phosphorus were added into growing media as 0, 50, 100 and 200 mg P2O5/kg with and without mycorrhiza applications. Phosphorus applications significantly increased yield criteria of lettuce according to the control treatment statistically. Mycorrhiza application also significantly increased plant diameter, plant dry weight and phosphor uptake by plant. The highest phosphorus uptakes by plants were determined in 200 mg P2O5/kg treatments as 88.8 mg P/pot with mycorrhiza and 83.1 mg P/pot without mycorrhiza application. In the control at 0 doses of phosphorus with mycorrhiza treatment, phosphorus uptake (69.9 mg P/pot, edible weight (84.36 g, dry weight (8.64 g and leaf number (28 of lettuce were higher than that (47.7 mg P/pot, 59.33 g, 6.75 g and 20, respectively in the control without mycorrhiza application. It was determined that mycorrhiza had positive effect on growth criteria and phosphorus nutrition by lettuce plant, and this effect decreased at higher phosphorus application rates.

  4. Environmental Phosphorus Recovery Based on Molecular Bioscavengers

    DEFF Research Database (Denmark)

    Gruber, Mathias Felix

    Phosphorus is a ubiquitous element of all known life and as such it is found throughout numerous key molecules related to various cellular functions. The supply of phosphorus is tightly linked to global food security, since phosphorus is used to produce agricultural fertilizers, without which...... it would not be possible to feed the world population. Sadly, the current supply of phosphorus is based on the gradual depletion of limited fossil reserves, and some estimates predict that within 15-25 years we will consume more phosphorus than we can produce. There is therefore a strong international...... pressure to develop sustainable phosphorus practices as well as new technologies for phosphorus recovery. Nature has spent billions of years refining proteins that interact with phosphates. This has inspired the present work where the overall ambitions are: to facilitate the development of a recovery...

  5. Carbon supported ultrafine gold phosphorus nanoparticles as highly efficient electrocatalyst for alkaline ethanol oxidation reaction

    International Nuclear Information System (INIS)

    Li, Tongfei; Fu, Gengtao; Su, Jiahui; Wang, Yi; Lv, Yinjie; Zou, Xiuyong; Zhu, Xiaoshu; Xu, Lin; Sun, Dongmei; Tang, Yawen

    2017-01-01

    Graphical abstract: We develop a new kind of carbon supported gold-phosphorus (Au-P/C) electrocatalyst by a facile and novel phosphorus reduction method, and demonstrate the Au-P/C is a highly active and stable electrocatalyst for the ethanol oxidation reaction. - Highlights: • Au-P/C catalyst is synthesized by a facile and novel white-phosphorus reduce method. • AuP particles with ultrafine particle-size are uniformly dispersed on carbon support. • Au-P/C catalyst exhibits much higher content of P 0 than reported metal/P catalysts. • Au-P/C catalysts show excellent catalytic properties for ethanol oxidation reaction. - Abstract: Herein, we develop a new kind of carbon supported gold-phosphorus (Au-P/C) electrocatalyst for the alkaline ethanol oxidation reaction (EOR). The Au-P/C catalysts with different Au/P ratio (i.e., AuP/C, Au 3 P 2 /C and Au 4 P 3 /C) can be obtained by a facile and novel hot-reflux method with white phosphorus (P 4 ) as reductant and ethanol as solvent. The crystal structure, composition and particle-size of the Au-P/C catalysts are investigated by X-ray diffraction (XRD), Energy Dispersive Spectrometer (EDS), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), etc. The results demonstrate that Au-P/C catalysts present an alloy phase with the high content of P, ultrafine particle-size and high dispersity on carbon support, which results in excellent electrocatalytic activity and stability towards the EOR compared with that of the free-phosphorus Au/C catalyst. In addition, among the various Au-P/C catalysts with different Au/P ratio, the AuP/C sample exhibits the best electrocatalytic performance in comparison with other Au 3 P 2 /C and Au 4 P 3 /C samples.

  6. Influences on the Emissions of Bacterial Plasmas Generated through Nanosecond Laser-Induced Breakdown Spectroscopy

    Science.gov (United States)

    Malenfant, Dylan J.

    In the past decade, laser-induced breakdown spectroscopy has been shown to provide compositional data that can be used for discrimination between bacterial specimens at the strain level. This work demonstrates the viability of this technique in a clinical setting. Studies were conducted to investigate the impact of emissions generated by a nitrocellulose filter paper background on the classification of four species: E. coli, S. epidermidis, M. smegmatis, and P. aeruginosa. Limits of detection were determined as 48+/-12 kCFU per ablation event for new mounting procedures using standard diagnostic laboratory techniques, and a device for centrifuge filtration was designed for sampling from low-titer bacterial suspensions. Plasma emissions from samples grown at biological levels of magnesium, zinc, and glucose were shown not to deviate from controls. A limit of detection for environmental zinc was found to be 11 ppm. Discrimination with heat-killed samples was demonstrated, providing a sterile diagnostic environment.

  7. Modelling phosphorus transport and its response to climate change at upper stream of Poyang Lake-the largest fresh water lake in China

    Science.gov (United States)

    Jiang, Sanyuan; Zhang, Qi

    2017-04-01

    Phosphorus losses from excessive fertilizer application and improper land exploitation were found to be the limiting factor for freshwater quality deterioration and eutrophication. Phosphorus transport from uplands to river is related to hydrological, soil erosion and sediment transport processes, which is impacted by several physiographic and meteorological factors. The objective of this study was to investigate the spatiotemporal variation of phosphorus losses and response to climate change at a typical upstream tributary (Le'An river) of Poyang Lake. To this end, a process-oriented hydrological and nutrient transport model HYPE (Hydrological Predictions for the Environment) was set up for discharge and phosphorus transport simulation at Le'An catchment. Parameter ESTimator (PEST) was combined with HYPE model for parameter sensitivity analysis and optimisation. In runoff modelling, potential evapotranspiration rate of the dominant land use (forest) is most sensitive; parameters of surface runoff rate and percolation capacity for the red soil are also very sensitive. In phosphorus transport modelling, the exponent of equation for soil erosion processes induced by surface runoff is most sensitive, coefficient of adsorption/desorption processes for red soil is also very sensitive. Flow dynamics and water balance were simulated well at all sites for the whole period (1978-1986) with NSE≥0.80 and PBIAS≤14.53%. The optimized hydrological parameter set were transferable for the independent period (2009-2010) with NSE≥0.90 and highest PBIAS of -7.44% in stream flow simulation. Seasonal dynamics and balance of stream water TP (Total Phosphorus ) concentrations were captured satisfactorily indicated by NSE≥0.53 and highest PBIAS of 16.67%. In annual scale, most phosphorus is transported via surface runoff during heavy storm flow events, which may account for about 70% of annual TP loads. Based on future climate change analysis under three different emission

  8. Doping of ZnO nanowires using phosphorus diffusion from a spin-on doped glass source

    International Nuclear Information System (INIS)

    Bocheux, A.; Robin, I. C.; Bonaimé, J.; Hyot, B.; Feuillet, G.; Kolobov, A. V.; Fons, P.; Mitrofanov, K. V.; Tominaga, J.; Tamenori, Y.

    2014-01-01

    In this article, we report on ZnO nanowires that were phosphorus doped using a spin on dopant glass deposition and diffusion method. Photoluminescence measurements suggest that this process yields p-doped ZnO. The spatial location of P atoms was studied using x-ray near-edge absorption structure spectroscopy and it is concluded that the doping is amphoteric with P atoms located on both Zn and O sites

  9. Cerebral NMR spectroscopy to study intracellular space in vivo: methodological development for diffusion weighted spectroscopy at short time scale and for pH measurement using 31P detection

    International Nuclear Information System (INIS)

    Marchadour, Charlotte

    2013-01-01

    NMR spectroscopy is a unique modality to evaluate intracellular environment in vivo. Indeed observed molecules are specifically intracellular and generally have a biochemistry role and a specific cellular compartmentation. That could be a useful tool to understand cell functioning in their environment. My thesis work consisted in development of new sequence in both diffusion and phosphorus NMR spectroscopy.My first study was to develop a diffusion-weighted spectroscopy at ultra-short diffusion time to look at the anomalous diffusion in the rat brain. ADC evolution as a function of time shows that brain metabolites motion is mainly due to random diffusion and that active transport (if exist) are negligible. Data modeling evidences that diffusion at short diffusion time is sensitive to cytoplasm viscosity and short scale crowding. In collaboration with the pharmaceutical company, this technique was chosen to follow up transgenic mice (rTg4510), model of tau pathology. Preliminary results show significant differences of ADC at an early stage of neuro-degenerescence (3 and 6 months).Phosphorus spectroscopy allows observation of metabolites directly implicated in energetic processes. During this thesis, localization sequences were developed to measure intracellular pH in the primate striatum. These sequences are supposed to be used to evaluate the potential of pH as a bio-marker of neuro-degenerescence in a phenotypic model of the Huntington disease in the non-human primate. (author) [fr

  10. Scrape-off layer-induced beam density fluctuations and their effect on beam emission spectroscopy

    Science.gov (United States)

    Moulton, D.; Marandet, Y.; Tamain, P.; Dif-Pradalier, G.

    2015-07-01

    A statistical model is presented to calculate the magnitude of beam density fluctuations generated by a turbulent scrape-off layer (SOL). It is shown that the SOL can induce neutral beam density fluctuations of a similar magnitude to the plasma density fluctuations in the core, potentially corrupting beam emission spectroscopy measurements. The degree of corruption is quantified by combining simulations of beam and plasma density fluctuations inside a simulated measurement window. A change in pitch angle from the separatrix to the measurement window is found to reduce the effect of beam fluctuations, whose largest effect is to significantly reduce the measured correlation time.

  11. Elemental analysis of halogens using molecular emission by laser-induced breakdown spectroscopy in air

    Energy Technology Data Exchange (ETDEWEB)

    Gaft, M.; Nagli, L.; Eliezer, N.; Groisman, Y. [Laser Distance Spectrometry, 9 Mota Gur St., Petah Tikva 49514 (Israel); Forni, O. [Université de Toulouse, UPS-OMP, IRAP, Toulouse (France); CNRS, IRAP, 9 Av. Colonel Roche, BP 44346, F-31028 Toulouse cedex 4 (France)

    2014-08-01

    Fluorine and chlorine do not produce atomic and ionic line spectra of sufficient intensity to permit their detection by laser-induced breakdown spectroscopy. They do, however, combine with alkali-earths and other elements to form molecules whose spectra may be easily identified, enabling detection in ambient conditions with much higher sensitivity than using F I and Cl I atomic lines. - Highlights: • We studied laser induced breakdown spectra of halogens with alkali-earth elements. • Emission and temporal behavior of CaF and CaCl molecules were determined. • Sensitivity of F and Cl detection by molecules and atoms was compared.

  12. Using FTIR-photoacoustic spectroscopy for phosphorus speciation analysis of biochars

    DEFF Research Database (Denmark)

    Bekiaris, Georgios; Peltre, Clément; Jensen, Lars Stoumann

    2016-01-01

    In the last decade, numerous studies have evaluated the benefits of biochar for improving soil quality. The purposes of the current study were to use Fourier transform infrared-photoacoustic spectroscopy (FTIR-PAS) to analyse P species in biochar and to determine the effect of pyrolysis temperatu...

  13. Traps for phosphorus adsorption

    International Nuclear Information System (INIS)

    Montoya, Nawer D; Villegas, Wilson E; Rodriguez, Lino M; Taborda, Nelson; Montes de C, Consuelo

    2001-01-01

    Several AL 2 O 3 supported oxides such as: NiO, CuO, Co 2 O 3 BaO, CeO 2 and ZnO were investigated for phosphorus adsorption. Zno/y-Al 2 O 3 exhibited the highest phosphorus adsorption capacity. However, since it diminishes the activity of to the reaction mixture it should be located upstream of the NoX catalyst, i.e. 0,3% Pd-H-MOR, in order to protect it against p poisoning. The treatment procedure with citric acid was effective for the removal of more than 70% phosphorus from the adsorbent, ZnO/y-Al 2 O 3

  14. Thermal Infrared Emission Spectroscopy of Synthetic Allophane and its Potential Formation on Mars

    Science.gov (United States)

    Rampe, E. B.; Kraft, M. D.; Sharp, T. G.; Golden, D. C.; Ming, Douglas W.

    2010-01-01

    Allophane is a poorly-crystalline, hydrous aluminosilicate with variable Si/Al ratios approx.0.5-1 and a metastable precursor of clay minerals. On Earth, it forms rapidly by aqueous alteration of volcanic glass under neutral to slightly acidic conditions [1]. Based on in situ chemical measurements and the identification of alteration phases [2-4], the Martian surface is interpreted to have been chemically weathered on local to regional scales. Chemical models of altered surfaces detected by the Mars Exploration Rover Spirit in Gusev crater suggest the presence of an allophane-like alteration product [3]. Thermal infrared (TIR) spectroscopy and spectral deconvolution models are primary tools for determining the mineralogy of the Martian surface [5]. Spectral models of data from the Thermal Emission Spectrometer (TES) indicate a global compositional dichotomy, where high latitudes tend to be enriched in a high-silica material [6,7], interpreted as high-silica, K-rich volcanic glass [6,8]. However, later interpretations proposed that the high-silica material may be an alteration product (such as amorphous silica, clay minerals, or allophane) and that high latitude surfaces are chemically weathered [9-11]. A TIR spectral library of pure minerals is available for the public [12], but it does not contain allophane spectra. The identification of allophane on the Martian surface would indicate high water activity at the time of its formation and would help constrain the aqueous alteration environment [13,14]. The addition of allophane to the spectral library is necessary to address the global compositional dichotomy. In this study, we characterize a synthetic allophane by IR spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM) to create an IR emission spectrum of pure allophane for the Mars science community to use in Martian spectral models.

  15. Complete chemical analysis of produced water by modern inductively coupled plasma spectroscopy (ICP)

    Energy Technology Data Exchange (ETDEWEB)

    Graham, G M; Sorbie, K S; Johnston, A; Boak, L S

    1997-12-31

    ICP (Inductively Coupled Plasma) spectroscopy is recognised as a very effective tool for monitoring ion compositions in many different waters. It has also been used by a number of laboratories to determine residual levels of phosphonate (PH) scale inhibitors in produced waters, based on phosphorus content. Until recently, it had not been used effectively to monitor phosphino-polycarboxylate (PPCA) returns. Large errors had frequently been observed where it had been applied. The poor detection limits and accuracy obtained for PPCA inhibitors relates to much lower amount of phosphorus present when compared with a typical phosphonate inhibitor. This paper demonstrates the effectiveness of IPC detection for PPCA and other phosphorus containing inhibitors by the use of modern instruments without the need of pre-treatment. 6 refs., 3 figs., 10 tabs.

  16. Phosphorus recycling from an unexplored source by polyphosphate accumulating microalgae and cyanobacteria – a step to phosphorus security in agriculture

    Directory of Open Access Journals (Sweden)

    Chandan eMukherjee

    2015-12-01

    Full Text Available Phosphorus (P, an essential element required for crop growth has no substitute. The global food security depends on phosphorus availability in soil for crop production. World phosphorus reserves are fast depleting and with an annual increase of 2.3% in phosphorus demand, the current reserves will be exhausted in coming 50-100 years. India and other Western countries are forced to import phosphorus fertilizers at high costs to meet their agricultural demands due to uneven distribution of phosphate rocks on earth. The present study from India, aims to draw attention to an unnoticed source of phosphorus being wasted as parboiled rice mill effluent and subsequent bio-recovery of the valuable element from this unconventional source. The research was conducted in West Bengal, India, a state with the highest number of parboiled rice mills where its effluent carries on an average ~40 mg/L of soluble phosphorus. Technology to recover and recycle this wastewater P in India in a simple, inexpensive mode is yet to be optimized. Our strategy to use microalgae, Chlorella sp. and cyanobacteria, Cyanobacterium sp., Lyngbya sp. and Anabaena sp. to sequester the excess phosphorus from the effluent as polyphosphate inclusions and its subsequent recycling as slow and moderate release phosphorus biofertilizers to aid plant growth, preventing phosphorus loss and pollution, is a contemporary venture to meet the need of the hour. These polyphosphate accumulating microorganisms play a dual role of remediation and recovery of phosphorus, preliminarily validated in laboratory scale.

  17. The Metal-Halide Lamp Under Varying Gravity Conditions Measured by Emission and Laser Absorption Spectroscopy

    Science.gov (United States)

    Flikweert, A. J.; Nimalasuriya, T.; Kroesen, G. M. W.; Haverlag, M.; Stoffels, W. W.

    2009-11-01

    Diffusive and convective processes in the metal-halide lamp cause an unwanted axial colour segregation. Convection is induced by gravity. To understand the flow phenomena in the arc discharge lamp it has been investigated under normal laboratory conditions, micro-gravity (ISS and parabolic flights) and hyper-gravity (parabolic flights 2 g, centrifuge 1 g-10 g). The measurement techniques are webcam imaging, and emission and laser absorption spectroscopy. This paper aims to give an overview of the effect of different artificial gravity conditions on the lamp and compares the results from the three measurement techniques.

  18. Evaluation of Optical Depths and Self-Absorption of Strontium and Aluminum Emission Lines in Laser-Induced Breakdown Spectroscopy (LIBS).

    Science.gov (United States)

    Alfarraj, Bader A; Bhatt, Chet R; Yueh, Fang Yu; Singh, Jagdish P

    2017-04-01

    Laser-induced breakdown spectroscopy (LIBS) is a widely used laser spectroscopic technique in various fields, such as material science, forensic science, biological science, and the chemical and pharmaceutical industries. In most LIBS work, the analysis is performed using radiative transitions from atomic emissions. In this study, the plasma temperature and the product [Formula: see text] (the number density N and the absorption path length [Formula: see text]) were determined to evaluate the optical depths and the self-absorption of Sr and Al lines. A binary mixture of strontium nitrate and aluminum oxide was used as a sample, consisting of variety of different concentrations in powder form. Laser-induced breakdown spectroscopy spectra were collected by varying various parameters, such as laser energy, gate delay time, and gate width time to optimize the LIBS signals. Atomic emission from Sr and Al lines, as observed in the LIBS spectra of different sample compositions, was used to characterize the laser induced plasma and evaluate the optical depths and self-absorption of LIBS.

  19. Anisotropic Electron-Photon and Electron-Phonon Interactions in Black Phosphorus.

    Science.gov (United States)

    Ling, Xi; Huang, Shengxi; Hasdeo, Eddwi H; Liang, Liangbo; Parkin, William M; Tatsumi, Yuki; Nugraha, Ahmad R T; Puretzky, Alexander A; Das, Paul Masih; Sumpter, Bobby G; Geohegan, David B; Kong, Jing; Saito, Riichiro; Drndic, Marija; Meunier, Vincent; Dresselhaus, Mildred S

    2016-04-13

    Orthorhombic black phosphorus (BP) and other layered materials, such as gallium telluride (GaTe) and tin selenide (SnSe), stand out among two-dimensional (2D) materials owing to their anisotropic in-plane structure. This anisotropy adds a new dimension to the properties of 2D materials and stimulates the development of angle-resolved photonics and electronics. However, understanding the effect of anisotropy has remained unsatisfactory to date, as shown by a number of inconsistencies in the recent literature. We use angle-resolved absorption and Raman spectroscopies to investigate the role of anisotropy on the electron-photon and electron-phonon interactions in BP. We highlight, both experimentally and theoretically, a nontrivial dependence between anisotropy and flake thickness and photon and phonon energies. We show that once understood, the anisotropic optical absorption appears to be a reliable and simple way to identify the crystalline orientation of BP, which cannot be determined from Raman spectroscopy without the explicit consideration of excitation wavelength and flake thickness, as commonly used previously.

  20. Relative efficiency of different methods of phosphorus (32P) application on fertilizer phosphorus uptake by maize (zea may L.)

    International Nuclear Information System (INIS)

    Chaudhary, M.L.; Gupta, A.P.

    1975-01-01

    A green house study was conducted for comparing four methods of phosphorus application (broad cast, below the seed, one side and both sides of the seeds) at the rate of 60 ppm in sierozem soil of H issar (Haryana). Maize crop was planted in 50 cm. bottomless bitumin drums for 70 days i.e. upto tasseling stage. The plant samples were collected at jointing and tasseling stages of plant growth. The results revealed that the highest dry matter yield, total and fertilizer phosphorus uptake was observed when the phosphorus was applied below the seed, followed by both side application of phosphorus. The least yield, total and fertilizer phosphorus uptake were recorded when the phosphorus was broadcast at the time of sowing. (author)

  1. Facile Conversion of Red Phosphorus into Soluble Polyphosphide Anions by Reaction with Potassium Ethoxide.

    Science.gov (United States)

    Dragulescu-Andrasi, Alina; Miller, L Zane; Chen, Banghao; McQuade, D Tyler; Shatruk, Michael

    2016-03-14

    Soluble polyphosphide anions were successfully generated in a number of organic solvents by the reaction between shelf-stable red phosphorus and potassium ethoxide. The species were identified by (31)P NMR spectroscopy in solution and by X-ray crystal-structure determination of (Bu4N)2P16 in the solid state. The reaction was scaled up to gram quantities by using a flow-chemistry process. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Mössbauer emission study on 57Co doped carbon-supported Ni and Ni-Mo sulfide hydrotreating catalysts : the influence of phosphorus on the structure

    NARCIS (Netherlands)

    Crajé, M.W.J.; Beer, de V.H.J.; Kraan, van der A.M.

    1991-01-01

    In the present study it is demonstrated that Mössbauer emission spectroscopy (MES) can generate information on the various Ni phases present in sulfided Ni containing catalysts when a small amount of 57Co is used as a probe for Ni.Application of MES to 57Co:Ni(4.5)Mo(8.0)/C and 57Co:Ni(5.6)/C

  3. Three-dimensional modeling of beam emission spectroscopy measurements in fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Guszejnov, D.; Pokol, G. I. [Department of Nuclear Techniques, Budapest University of Technology and Economics, Association EURATOM, H-1111 Budapest (Hungary); Pusztai, I. [Nuclear Engineering, Applied Physics, Chalmers University of Technology, SE-412 96 Goeteborg (Sweden); Refy, D.; Zoletnik, S. [MTA Wigner FK RMI, Association EURATOM, Pf. 49, H-1525 Budapest (Hungary); Lampert, M. [Department of Nuclear Techniques, Budapest University of Technology and Economics, Association EURATOM, H-1111 Budapest (Hungary); MTA Wigner FK RMI, Association EURATOM, Pf. 49, H-1525 Budapest (Hungary); Nam, Y. U. [National Fusion Research Institute, Gwahangno 113, Daejeon 305-333 (Korea, Republic of)

    2012-11-15

    One of the main diagnostic tools for measuring electron density profiles and the characteristics of long wavelength turbulent wave structures in fusion plasmas is beam emission spectroscopy (BES). The increasing number of BES systems necessitated an accurate and comprehensive simulation of BES diagnostics, which in turn motivated the development of the Rate Equations for Neutral Alkali-beam TEchnique (RENATE) simulation code that is the topic of this paper. RENATE is a modular, fully three-dimensional code incorporating all key features of BES systems from the atomic physics to the observation, including an advanced modeling of the optics. Thus RENATE can be used both in the interpretation of measured signals and the development of new BES systems. The most important components of the code have been successfully benchmarked against other simulation codes. The primary results have been validated against experimental data from the KSTAR tokamak.

  4. Emission spectroscopy diagnostics of rare gases in the PNX-U facility

    International Nuclear Information System (INIS)

    Vetrov, S. I.; Spitsyn, A. V.; Shuvaev, D. A.; Yanchenkov, S. V.

    2006-01-01

    Results are presented from measurements of the electron temperature and neutral atom density in a low-temperature microwave plasma by the method of emission spectroscopy. The measurements were conducted in the PNX-U facility-a magnetic confinement system with a 'magnetic wall.' Multichord measurements of plasma radiation at a wavelength of 750.37 nm were performed with the help of an absolutely calibrated monochromator. The neutral atom density was calculated using the collisional-radiative model. The degree of plasma ionization near the axis of the facility was found to be close to unity. The electron temperature of the argon plasma was measured from the relative intensities of the spectral lines of neutral helium injected in small amounts into the plasma (the so-called helium thermometer method). At a low microwave heating power, the results of these measurements agree well with the results of probe measurements

  5. Contributions to total phosphorus intake: all sources considered.

    Science.gov (United States)

    Calvo, Mona S; Uribarri, Jaime

    2013-01-01

    High serum phosphorus is linked to poor health outcome and mortality in chronic kidney disease (CKD) patients before or after the initiation of dialysis. Dietary intake of phosphorus, a major determinant of serum phosphorus, seems to be systematically underestimated using the available software tools and generalized nutrient content databases. Several sources of dietary phosphorus including the addition of phosphorus ingredients in food processing, and phosphorus content of vitamin and mineral supplements and commonly used over-the-counter or prescription medications are not fully accounted for by the nutrient content databases and software programs in current clinical use or used in large population studies. In this review, we explore the many unknown sources of phosphorus in the food supply to identify all possible contributors to total phosphorus intake of Americans that have escaped inclusion in past intake estimates. Our goal is to help delineate areas for future interventions that will enable tighter control of dietary phosphorus intake, a critical factor to maintaining health and quality of life in CKD and dialysis patients. © 2012 Wiley Periodicals, Inc.

  6. Influence of integrated phosphorus supply and plant growth ...

    African Journals Online (AJOL)

    To guarantee a sufficient phosphorus supply for plants, a rapid and permanent mobilization of phosphorus from the labile phosphorus fractions is necessary, because phosphorus concentrations in soil solution are generally low. Several plant growth-promoting rhizobacteria (PGPR) have shown potential to enhance ...

  7. Updated Spitzer emission spectroscopy of bright transiting hot Jupiter HD 189733b

    Energy Technology Data Exchange (ETDEWEB)

    Todorov, Kamen O. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); Deming, Drake [Department of Astronomy, University of Maryland at College Park, College Park, MD 20742 (United States); Burrows, Adam [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Grillmair, Carl J., E-mail: todorovk@phys.ethz.ch [Spitzer Science Center, California Institute of Technology, Mail Stop 220-6, Pasadena, CA 91125 (United States)

    2014-12-01

    We analyze all existing secondary eclipse time series spectroscopy of hot Jupiter HD 189733b acquired with the now defunct Spitzer/Infrared Spectrograph (IRS) instrument. We describe the novel approaches we develop to remove the systematic effects and extract accurate secondary eclipse depths as a function of wavelength in order to construct the emission spectrum of the exoplanet. We compare our results with a previous study by Grillmair et al. that did not examine all data sets available to us. We are able to confirm the detection of a water feature near 6 μm claimed by Grillmair et al. We compare the planetary emission spectrum to three model families—based on isothermal atmosphere, gray atmosphere, and two realizations of the complex radiative transfer model by Burrows et al., adopted in Grillmair et al.'s study. While we are able to reject the simple isothermal and gray models based on the data at the 97% level just from the IRS data, these rejections hinge on eclipses measured within a relatively narrow wavelength range, between 5.5 and 7 μm. This underscores the need for observational studies with broad wavelength coverage and high spectral resolution, in order to obtain robust information on exoplanet atmospheres.

  8. Black phosphorus-based one-dimensional photonic crystals and microcavities.

    Science.gov (United States)

    Kriegel, Ilka; Toffanin, Stefano; Scotognella, Francesco

    2016-11-10

    The latest achievements in the fabrication of thin layers of black phosphorus (BP), toward the technological breakthrough of a phosphorene atomically thin layer, are paving the way for their use in electronics, optics, and optoelectronics. In this work, we have simulated the optical properties of one-dimensional photonic structures, i.e., photonic crystals and microcavities, in which few-layer BP is one of the components. The insertion of the 5-nm black phosphorous layers leads to a photonic band gap in the photonic crystals and a cavity mode in the microcavity that is interesting for light manipulation and emission enhancement.

  9. The Effect of Chemical Amendments Used for Phosphorus Abatement on Greenhouse Gas and Ammonia Emissions from Dairy Cattle Slurry: Synergies and Pollution Swapping.

    Science.gov (United States)

    Brennan, Raymond B; Healy, Mark G; Fenton, Owen; Lanigan, Gary J

    2015-01-01

    Land application of cattle slurry can result in incidental and chronic phosphorus (P) loss to waterbodies, leading to eutrophication. Chemical amendment of slurry has been proposed as a management practice, allowing slurry nutrients to remain available to plants whilst mitigating P losses in runoff. The effectiveness of amendments is well understood but their impacts on other loss pathways (so-called 'pollution swapping' potential) and therefore the feasibility of using such amendments has not been examined to date. The aim of this laboratory scale study was to determine how the chemical amendment of slurry affects losses of NH3, CH4, N2O, and CO2. Alum, FeCl2, Polyaluminium chloride (PAC)- and biochar reduced NH3 emissions by 92, 54, 65 and 77% compared to the slurry control, while lime increased emissions by 114%. Cumulative N2O emissions of cattle slurry increased when amended with alum and FeCl2 by 202% and 154% compared to the slurry only treatment. Lime, PAC and biochar resulted in a reduction of 44, 29 and 63% in cumulative N2O loss compared to the slurry only treatment. Addition of amendments to slurry did not significantly affect soil CO2 release during the study while CH4 emissions followed a similar trend for all of the amended slurries applied, with an initial increase in losses followed by a rapid decrease for the duration of the study. All of the amendments examined reduced the initial peak in CH4 emissions compared to the slurry only treatment. There was no significant effect of slurry amendments on global warming potential (GWP) caused by slurry land application, with the exception of biochar. After considering pollution swapping in conjunction with amendment effectiveness, the amendments recommended for further field study are PAC, alum and lime. This study has also shown that biochar has potential to reduce GHG losses arising from slurry application.

  10. The Effect of Chemical Amendments Used for Phosphorus Abatement on Greenhouse Gas and Ammonia Emissions from Dairy Cattle Slurry: Synergies and Pollution Swapping.

    Directory of Open Access Journals (Sweden)

    Raymond B Brennan

    Full Text Available Land application of cattle slurry can result in incidental and chronic phosphorus (P loss to waterbodies, leading to eutrophication. Chemical amendment of slurry has been proposed as a management practice, allowing slurry nutrients to remain available to plants whilst mitigating P losses in runoff. The effectiveness of amendments is well understood but their impacts on other loss pathways (so-called 'pollution swapping' potential and therefore the feasibility of using such amendments has not been examined to date. The aim of this laboratory scale study was to determine how the chemical amendment of slurry affects losses of NH3, CH4, N2O, and CO2. Alum, FeCl2, Polyaluminium chloride (PAC- and biochar reduced NH3 emissions by 92, 54, 65 and 77% compared to the slurry control, while lime increased emissions by 114%. Cumulative N2O emissions of cattle slurry increased when amended with alum and FeCl2 by 202% and 154% compared to the slurry only treatment. Lime, PAC and biochar resulted in a reduction of 44, 29 and 63% in cumulative N2O loss compared to the slurry only treatment. Addition of amendments to slurry did not significantly affect soil CO2 release during the study while CH4 emissions followed a similar trend for all of the amended slurries applied, with an initial increase in losses followed by a rapid decrease for the duration of the study. All of the amendments examined reduced the initial peak in CH4 emissions compared to the slurry only treatment. There was no significant effect of slurry amendments on global warming potential (GWP caused by slurry land application, with the exception of biochar. After considering pollution swapping in conjunction with amendment effectiveness, the amendments recommended for further field study are PAC, alum and lime. This study has also shown that biochar has potential to reduce GHG losses arising from slurry application.

  11. Characterization of phosphorus forms in lake macrophytes and algae by solution 31P nuclear magnetic resonance spectroscopy

    Science.gov (United States)

    Aquatic macrophytes and algae are important sources of phosphorus (P) in the lake environment that cause blooms of algae under certain biogeochemical conditions. However, the knowledge of forms of P in these plants and algae and their contribution to internal loads of lake P is very limited. Witho...

  12. Phosphorus determination by various substoichiometric methods

    International Nuclear Information System (INIS)

    Shigematsu, Toshio; Kudo, Kiyoshi

    1981-01-01

    Various substoichiometric methods have been classified from a view point of the substoichiometric separation. Based upon the substoichiometric separation, phosphorus was determined substoichiometrically by a direct method, a method of carrier amount variation and a comparison method for the irradiated sample. The direct method was applied to the determination of phosphorus in orchard leaves (SRM-1571). The analytical value was 0.23 +- 0.01%. Phosphorus in orchard leaves and spinach (SRM-1570) was determined by an ordinary method which devided the sample into equal parts in the method of carrier amount variation. Analytical values of orchard leaves and spinach were 0.22 +- 0.02% and 0.56 +- 0.04%, respectively. Moreover, a new modification of the method of carrier amount variation was studied by the use of various standard samples such as red phosphorus, spinach and orchard leaves. These standard samples were also employed for the determination of phosphorus in orchard leaves and 0.21 +- 0.01% was obtained. All these results are in good agreement with the value reported by NBS. The comparison method was applied to the determination of phosphorus in a semiconductor silicon single crystal. As a result of the correction of 32 P activity induced by the secondary nuclear reaction of 30 Si, 7.9 ppb and 3.1 ppb were obtained for the phosphorus concentrations in the single crystal silicon. (author)

  13. Visualizing alternative phosphorus scenarios for future food security

    Directory of Open Access Journals (Sweden)

    Tina-Simone Neset

    2016-10-01

    Full Text Available The impact of global phosphorus scarcity on food security has increasingly been the focus of scientific studies over the past decade. However, systematic analyses of alternative futures for phosphorus supply and demand throughout the food system are still rare and provide limited inclusion of key stakeholders. Addressing global phosphorus scarcity requires an integrated approach exploring potential demand reduction as well as recycling opportunities. This implies recovering phosphorus from multiple sources, such as food waste, manure and excreta, as well as exploring novel opportunities to reduce the long-term demand for phosphorus in food production such as changing diets. Presently, there is a lack of stakeholder and scientific consensus around priority measures. To therefore enable exploration of multiple pathways and facilitate a stakeholder dialogue on the technical, behavioral and institutional changes required to meet long-term future phosphorus demand, this paper introduces an interactive web-based tool, designed for visualizing global phosphorus scenarios in real-time. The interactive global phosphorus scenario tool builds on several demand and supply side measures that can be selected and manipulated interactively by the user. It provides a platform to facilitate stakeholder dialogue to plan for a soft landing and identify a suite of concrete priority options, such as investing in agricultural phosphorus use efficiency, or renewable fertilizers derived from phosphorus recovered from wastewater and food waste, to determine how phosphorus demand to meet future food security could be attained on a global scale in 2040 and 2070. This paper presents four example scenarios, including (1 the potential of full recovery of human excreta, (2 the challenge of a potential increase in non-food phosphorus demand, (3 the potential of a decreased animal product consumption, and (4 the potential decrease in phosphorus demand from increased efficiency

  14. Visualizing Alternative Phosphorus Scenarios for Future Food Security.

    Science.gov (United States)

    Neset, Tina-Simone; Cordell, Dana; Mohr, Steve; VanRiper, Froggi; White, Stuart

    2016-01-01

    The impact of global phosphorus scarcity on food security has increasingly been the focus of scientific studies over the past decade. However, systematic analyses of alternative futures for phosphorus supply and demand throughout the food system are still rare and provide limited inclusion of key stakeholders. Addressing global phosphorus scarcity requires an integrated approach exploring potential demand reduction as well as recycling opportunities. This implies recovering phosphorus from multiple sources, such as food waste, manure, and excreta, as well as exploring novel opportunities to reduce the long-term demand for phosphorus in food production such as changing diets. Presently, there is a lack of stakeholder and scientific consensus around priority measures. To therefore enable exploration of multiple pathways and facilitate a stakeholder dialog on the technical, behavioral, and institutional changes required to meet long-term future phosphorus demand, this paper introduces an interactive web-based tool, designed for visualizing global phosphorus scenarios in real time. The interactive global phosphorus scenario tool builds on several demand and supply side measures that can be selected and manipulated interactively by the user. It provides a platform to facilitate stakeholder dialog to plan for a soft landing and identify a suite of concrete priority options, such as investing in agricultural phosphorus use efficiency, or renewable fertilizers derived from phosphorus recovered from wastewater and food waste, to determine how phosphorus demand to meet future food security could be attained on a global scale in 2040 and 2070. This paper presents four example scenarios, including (1) the potential of full recovery of human excreta, (2) the challenge of a potential increase in non-food phosphorus demand, (3) the potential of decreased animal product consumption, and (4) the potential decrease in phosphorus demand from increased efficiency and yield gains in

  15. Uranium(VI) speciation by spectroscopy

    International Nuclear Information System (INIS)

    Meinrath, G.

    1997-01-01

    The application of UV-Vis and time-resolved laser-induced fluorescence (TRLF) spectroscopies to direct of uranium(VI) in environmental samples offers various prospects that have, however, serious limitations. While UV-Vis spectroscopy is probably not sensitive enough to detect uranium(VI) species in the majority of environmental samples, TRLFS is principially able to speciate uranium(VI) at very low concentration levels in the nanomol range. Speciation by TRLFS can be based on three parameters: excitation spectrum, emission spectrum and lifetime of the fluorescence emission process. Due to quenching effects, the lifetime may not be expected to be as characteristics as, e.g., the emission spectrum. Quenching of U(VI) fluorescence by reaction with organic substances, inorganic ions and formation of carbonate radicals is one important limiting factor in the application of U(VI) fluorescence spectroscopy. Fundamental photophysical criteria are illustrated using UV-Vis and fluorescence spectra of U(VI) hydrolysis and carbonato species as examples. (author)

  16. Phosphorus K4 Crystal: A New Stable Allotrope

    OpenAIRE

    Jie Liu; Shunhong Zhang; Yaguang Guo; Qian Wang

    2016-01-01

    The intriguing properties of phosphorene motivate scientists to further explore the structures and properties of phosphorus materials. Here, we report a new allotrope named K 4 phosphorus composed of three-coordinated phosphorus atoms in non-layered structure which is not only dynamically and mechanically stable, but also possesses thermal stability comparable to that of the orthorhombic black phosphorus (A17). Due to its unique configuration, K 4 phosphorus exhibits exceptional properties: i...

  17. In vivo NMR spectroscopy of the liver. Spectroscopie RMN du foie in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Jehenson, P.; Cuenod, C.A.; Syrota, A. (CEA, 91 - Orsay (FR). Service Hospitalier Frederic Joliot)

    1989-01-01

    The application of in vivo MR spectroscopy to the study of the liver is currently an expanding field of research. Owing to technical difficulties, the results obtained thus far were mainly those of animal observations. Several nuclei have been considered: hydrogen, phosphorus, carbon or fluorine. This non-traumatic method allows following and quantifying the various metabolic pathways, especially during hepatic diseases. The major metabolic pathways, i.e. neoglycogenesis, glycogenolysis, Krebs' cycle, etc., are studied, as well as their alterations during diseases such as ischemia, diabetes or alcoholism. The development of this promising technique requires the cooperation of various clinical and fundamental disciplines.

  18. Advanced techniques for actinide spectroscopy (ATAS 2012). Abstract book

    Energy Technology Data Exchange (ETDEWEB)

    Foerstendorf, Harald; Mueller, Katharina; Steudtner, Robin [eds.

    2012-07-01

    The abstract book of the International workshop on advanced techniques for actinide spectroscopy (ATAS 2012) include contributions concerning the following issues: environmental applications, NMR spectroscopy, vibrational spectroscopy, X-ray spectroscopy and theory, technical application: separation processes, emission spectroscopy.

  19. Advanced techniques for actinide spectroscopy (ATAS 2012). Abstract book

    International Nuclear Information System (INIS)

    Foerstendorf, Harald; Mueller, Katharina; Steudtner, Robin

    2012-01-01

    The abstract book of the International workshop on advanced techniques for actinide spectroscopy (ATAS 2012) include contributions concerning the following issues: environmental applications, NMR spectroscopy, vibrational spectroscopy, X-ray spectroscopy and theory, technical application: separation processes, emission spectroscopy.

  20. Yellow phosphorus-induced Brugada phenocopy.

    Science.gov (United States)

    Dharanipradab, Mayakrishnan; Viswanathan, Stalin; Kumar, Gokula Raman; Krishnamurthy, Vijayalatchumy; Stanley, Daphene Divya

    Metallic phosphides (of aluminum and phosphide) and yellow phosphorus are commonly used rodenticide compounds in developing countries. Toxicity of yellow phosphorus mostly pertains to the liver, kidney, heart, pancreas and the brain. Cardiotoxicity with associated Brugada ECG pattern has been reported only in poisoning with metallic phosphides. Brugada phenocopy and hepatic dysfunction were observed in a 29-year-old male following yellow phosphorus consumption. He had both type 1 (day1) and type 2 (day2) Brugada patterns in the electrocardiogram, which resolved spontaneously by the third day without hemodynamic compromise. Toxins such as aluminum and zinc phosphide have been reported to induce Brugada ECG patterns due to the generation of phosphine. We report the first case of yellow phosphorus-related Brugada phenocopy, without hemodynamic compromise or malignant arrhythmia. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Probing Transient Valence Orbital Changes with Picosecond Valence-to-Core X-ray Emission Spectroscopy

    DEFF Research Database (Denmark)

    March, Anne Marie; Assefa, Tadesse A.; Boemer, Christina

    2017-01-01

    We probe the dynamics of valence electrons in photoexcited [Fe(terpy)2]2+ in solution to gain deeper insight into the Fe ligand bond changes. We use hard X-ray emission spectroscopy (XES), which combines element specificity and high penetration with sensitivity to orbital structure, making...... valence orbitals to the nascent core-hole. Vtc-XES offers particular insight into the molecular orbitals directly involved in the light-driven dynamics; a change in the metal ligand orbital overlap results in an intensity reduction and a blue energy shift in agreement with our theoretical calculations...... and more subtle features at the highest energies reflect changes in the frontier orbital populations....

  2. Space-resolved characterization of high frequency atmospheric-pressure plasma in nitrogen, applying optical emission spectroscopy and numerical simulation

    International Nuclear Information System (INIS)

    Rajasekaran, Priyadarshini; Ruhrmann, Cornelia; Bibinov, Nikita; Awakowicz, Peter

    2011-01-01

    Averaged plasma parameters such as electron distribution function and electron density are determined by characterization of high frequency (2.4 GHz) nitrogen plasma using both experimental methods, namely optical emission spectroscopy (OES) and microphotography, and numerical simulation. Both direct and step-wise electron-impact excitation of nitrogen emissions are considered. The determination of space-resolved electron distribution function, electron density, rate constant for electron-impact dissociation of nitrogen molecule and the production of nitrogen atoms, applying the same methods, is discussed. Spatial distribution of intensities of neutral nitrogen molecule and nitrogen molecular ion from the microplasma is imaged by a CCD camera. The CCD images are calibrated using the corresponding emissions measured by absolutely calibrated OES, and are then subjected to inverse Abel transformation to determine space-resolved intensities and other parameters. The space-resolved parameters are compared, respectively, with the averaged parameters, and an agreement between them is established. (paper)

  3. Reducing phosphorus runoff and leaching from poultry litter with alum: Twenty-year small plot and paired-watershed studies

    Science.gov (United States)

    Treating poultry litter with alum is a best management practice (BMP) for lowering ammonia (NH3) emissions and phosphorus (P) runoff losses. The objective of this study was to evaluate the long-term (20 year) effects of alum-treated and untreated poultry litter applications on P availability, leachi...

  4. Nitrogen mineralization and nitrous oxide emissions in a sandy soil amended with low-phosphorus broiler litter

    Science.gov (United States)

    Recurrent land application of broiler litter in regions with a high concentration of poultry farms result in soils with phosphorus (P) far beyond the agronomic requirement of crops. A new waste treatment technology developed by USDA-ARS, called “Quick Wash”, chemically extracts and recovers P from b...

  5. Determination of phosphorus using derivative neutron activation

    International Nuclear Information System (INIS)

    Scindia, Y.M.; Nair, A.G.C.; Reddy, A.V.R.; Manohar, S.B.

    2002-01-01

    For the determination of phosphorus in different matrices, the derivative neutron activation analysis is especially applicable to aqueous samples, since the conventional neutron activation analysis is not useful for the determination of phosphorus. Phosphorus when reacted with ammonium molybdate 4 hydrate and ammonium metavanadate forms molybdo vanado phosphoric acid. This complex is preconcentrated by extracting into methyl isobutyl ketone. The organic phase containing the molybdo vanado phosphoric acid is neutron activated and the phosphorus is determined through the activation product of 52 V. Preparation of this complex, its stoichiometry, application to trace level determination of phosphorus and improved detection limit are discussed. This method was applied for the analysis of industrial effluent samples. (author)

  6. Guiding phosphorus stewardship for multiple ecosystem services

    Science.gov (United States)

    Phosphorus is vital to agricultural production and water quality regulation. While the role of phosphorus in agriculture and water quality has been studied for decades, the benefits of sustainable phosphorus use and management for society due to its downstream impacts on multiple ecosystem services...

  7. Handbook of Applied Solid State Spectroscopy

    CERN Document Server

    Vij, D. R

    2006-01-01

    Solid-State spectroscopy is a burgeoning field with applications in many branches of science, including physics, chemistry, biosciences, surface science, and materials science. Handbook of Applied Solid-State Spectroscopy brings together in one volume information about various spectroscopic techniques that is currently scattered in the literature of these disciplines. This concise yet comprehensive volume covers theory and applications of a broad range of spectroscopies, including NMR, NQR, EPR/ESR, ENDOR, scanning tunneling, acoustic resonance, FTIR, auger electron emission, x-ray photoelectron emission, luminescence, and optical polarization, and more. Emphasis is placed on fundamentals and current methods and procedures, together with the latest applications and developments in the field.

  8. Impacts of anthropic pressures on soil phosphorus availability, concentration, and phosphorus forms in sediments in a Southern Brazilian watershed

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, Joao Batista Rossetto; Rheinheimer dos Santos, Danilo; Goncalves, Celso Santos; Copetti, Andre Carlos Cruz [Dept. de Solos, Univ. Federal de Santa Maria, Centro de Ciencias Rurais, Santa Maria, RS (Brazil); Bortoluzzi, Edson Campanhola [Faculdade de Agronomia e Medicina Veterinaria da Univ. de Passo Fundo, RS (Brazil); Tessier, Daniel [Inst. National de la Recherche Agronomique, Versailles (France)

    2010-04-15

    Purpose: The transfer of soil sediments and phosphorus from terrestrial to aquatic systems is a common process in agricultural lands. The aims of this paper are to quantify the soil phosphorus availability and to characterize phosphorus forms in soil sediments as contaminant agents of waters as a function of anthropic pressures. Materials and methods On three subwatersheds with different anthropic pressure, water and sediment samples were collected automatically in upstream and downstream discharge points in six rainfall events during the tobacco growing season. Phosphorus desorption capacity from soil sediments was estimated by successive extractions with anion exchange resins. First-order kinetic models were adjusted to desorption curves for estimating potentially bioavailable particulate phosphorus, desorption rate constant, and bioavailable particulate phosphorus. Results and discussion The amount of bioavailable particulate phosphorus was directly correlated with the iron oxide content. The value of desorption rate constant was directly related with the total organic carbon and inversely with the iron oxide contents. Phosphate ions were released to solution, on average, twice as rapidly from sediments collected in subwatersheds with low anthropic activity than from those ones of highly anthropic subwatersheds. Anthropic pressure on watershed can engender high sediment discharge, but these solid particles seem to present low phosphorus-releasing capacity to water during transport due to the evidenced high affinity between phosphorus and iron oxide from sediments. Conclusions Anthropic pressure was related with sediment concentration and phosphorus release to aquatic systems. While natural vegetation along streams plays a role on soil and water depuration, it is unable to eliminate the phosphorus inputs intrinsic to the agricultural-intensive systems. Recommendations and perspectives The contamination of water in watershed by phosphates is facilitated by the

  9. Phosphorus-containing macrocyclic compounds: synthesis and properties

    International Nuclear Information System (INIS)

    Knyazeva, I R; Burilov, Alexander R; Pudovik, Michael A; Habicher, Wolf D

    2013-01-01

    Main trends in the development of methods for the synthesis of phosphorus-containing macrocyclic compounds in the past 15 years are considered. Emphasis is given to reactions producing macrocyclic structures with the participation of a phosphorus atom and other functional groups involved in organophosphorus molecules and to modifications of macrocycles by phosphorus compounds in different valence states. Possibilities of the practical application of phosphorus-containing macrocyclic compounds in difference areas of science and engineering are discussed. The bibliography includes 205 references.

  10. Intergranular fracture stress and phosphorus grain boundary segregation of a Mn-Ni-Mo steel

    International Nuclear Information System (INIS)

    Naudin, C.; Frund, J.M.; Pineau, A.

    1999-01-01

    Nuclear Reactor Pressure Vessel (RPV) steel A508 class 3 which is a low alloyed steel is not usually sensitive to reversible temper embrittlement when properly heat treated. However heterogeneous zones may be present in particular near the inner side of the vessel. These zones result from the segregation of the alloying elements (C, Mn, Ni, Mo) and impurities (S, P) taking place during solidification of the material. They are called segregated zones (or ghost lines). They can reach 2 mm thick along the radius and 30 mm long through the circumferential direction. Their susceptibility to reversible temper embrittlement is mainly due to grain boundary phosphorus segregation triggering brittle intergranular fracture when the material is tested at low temperature. In this material like in other steels the influence of some other alloying elements (Mo, Mn...) is clearly significant and should also be taken into account. But phosphorus effect has proved to be predominant. The aim of the present study is therefore to find out a quantitative relationship between grain boundary phosphorus segregation and critical intergranular fracture stress. A synthetic steel with a chemical composition representative of an average segregated zone was prepared for the present study. A number of heat treatments were applied to reach different embrittlement conditions. Then brittle fracture properties were obtained by performing cryogenic fracture tests on notched tensile specimens while the corresponding grain boundary phosphorus levels were measured by Auger electron spectroscopy. Systematic fractographic observations were carried out. Moreover an attempt to determine the influence of temperature on the critical intergranular fracture stress was made

  11. Localization of the antimony impurity atoms in the PbTe lattice determined by the Moessbauer emission spectroscopy

    International Nuclear Information System (INIS)

    Masterov, V.F.; Nasredinov, F.S.; Nemov, S.A.; Seregin, P.P.; Troitskaya, N.N.; Bondarevskij, S.I.

    1997-01-01

    The 119 Sb ( 119m Sn) emission Moessbauer spectroscopy has shown that a localization of the antimony impurity atoms in the PbTe lattice is affected by the conductivity type of the host material, the antimony atoms occupied mainly anion and cation sites in n-type and p-type samples, respectively. The 119 Sn impurity in the anion sublattice of PbTe formed an decay. Its charge state was shown to be independent of the Fermi level position

  12. Biological phosphorus uptake under anoxic and aerobic conditions

    DEFF Research Database (Denmark)

    Kerrn-Jespersen, Jens Peter; Henze, Mogens

    1993-01-01

    Biological phosphorus removal was investigated under anoxic and aerobic conditions. Tests were made to establish whether phosphorus accumulating bacteria can take up phosphate under anoxic conditions and thus utilise nitrate as oxidant. Furthermore, it was tested how the amount of organic matter...... as oxidant. The phosphorus uptake was more rapid under aerobic conditions than under anoxic conditions. The explanation of this is that all phosphorus accumulating bacteria take up phosphate under aerobic conditions, whereas only part of the phosphorus accumulating bacteria take up phosphate under anoxic...

  13. Evaluation of self-absorption coefficients of aluminum emission lines in laser-induced breakdown spectroscopy measurements

    International Nuclear Information System (INIS)

    El Sherbini, A.M.; El Sherbini, Th.M.; Hegazy, H.; Cristoforetti, G.; Legnaioli, S.; Palleschi, V.; Pardini, L.; Salvetti, A.; Tognoni, E.

    2005-01-01

    In quantitative Laser Induced Breakdown Spectroscopy (LIBS) measurements it is essential to account for the effect of self-absorption on the emission lines intensity. In order to quantify this effect, in this paper we propose a simple method for evaluating the ratio between the actual measured line intensity and the intensity expected in absence of self-absorption and, if necessary, correcting the effect of self-absorption on line intensity. The method, based on a homogeneous plasma model, is applicable when the plasma electron density is known and in particular to lines whose Stark broadening parameter is available

  14. Spectroscopic studies of the origin of radiation-induced degradation in phosphorus-doped optical fibers and preforms

    International Nuclear Information System (INIS)

    Origlio, G.; Messina, F.; Cannas, M.; Girard, S.; Boukenter, A.; Ouerdane, Y.

    2010-01-01

    In this paper, we study the radiation-induced point defects related to the phosphorus element that is commonly used to improve the optical properties of silica-based glasses but is responsible of a dramatic increase in their radiation sensitivity. To this aim, the influence of x-ray irradiation on prototype phosphorus-doped canonical fibers and their related preforms was investigated by in situ radiation induced attenuation (RIA), optical absorption, and electron spin resonance (ESR) spectroscopy. The RIA spectra in the (1.5-5 eV) range, can be explained by the presence of at least three absorption bands induced by radiation exposure. Additionally the X-dose dependence of such bands was studied. The main responsible defect for these absorption peaks was the phosphorus oxygen hole center (POHC) center, whose presence was also detected by ESR measurements both in irradiated fibers and preforms, together with the lineshape of the so called P2 defect. Correlations between the RIA bands and the ESR results allow us to assign the 2.3 and 3.0 eV bands to POHCs and to propose a scheme for the simultaneous creation of POHC and P2 defects after x-ray exposure.

  15. Sample preparation techniques in trace element analysis by X-ray emission spectroscopy

    International Nuclear Information System (INIS)

    Valkovic, V.

    1983-11-01

    The report, written under a research contract with the IAEA, contains a detailed presentation of the most difficult problem encountered in the trace element analysis by methods of the X-ray emission spectroscopy, namely the sample preparation techniques. The following items are covered. Sampling - with specific consideration of aerosols, water, soil, biological materials, petroleum and its products, storage of samples and their handling. Pretreatment of samples - preconcentration, ashing, solvent extraction, ion exchange and electrodeposition. Sample preparations for PIXE - analysis - backings, target uniformity and homogeneity, effects of irradiation, internal standards and specific examples of preparation (aqueous, biological, blood serum and solid samples). Sample preparations for radioactive sources or tube excitation - with specific examples (water, liquid and solid samples, soil, geological, plants and tissue samples). Finally, the problem of standards and reference materials, as well as that of interlaboratory comparisons, is discussed

  16. Optical emission spectroscopy of metal vapor dominated laser-arc hybrid welding plasma

    International Nuclear Information System (INIS)

    Ribic, B.; DebRoy, T.; Burgardt, P.

    2011-01-01

    During laser-arc hybrid welding, plasma properties affect the welding process and the weld quality. However, hybrid welding plasmas have not been systematically studied. Here we examine electron temperatures, species densities, and electrical conductivity for laser, arc, and laser-arc hybrid welding using optical emission spectroscopy. The effects of arc currents and heat source separation distances were examined because these parameters significantly affect weld quality. Time-average plasma electron temperatures, electron and ion densities, electrical conductivity, and arc stability decrease with increasing heat source separation distance during hybrid welding. Heat source separation distance affects these properties more significantly than the arc current within the range of currents considered. Improved arc stability and higher electrical conductivity of the hybrid welding plasma result from increased heat flux, electron temperatures, electron density, and metal vapor concentrations relative to arc or laser welding.

  17. Application of ultraviolet fluorometry and excitation-emission matrix spectroscopy (EEMS) to fingerprint oil and chemically dispersed oil in seawater.

    Science.gov (United States)

    Bugden, J B C; Yeung, C W; Kepkay, P E; Lee, K

    2008-04-01

    Excitation-emission matrix spectroscopy (EEMS) was used to characterize the ultra violet fluorescence fingerprints of eight crude oils (with a 14,470-fold range of dynamic viscosity) in seawater. When the chemical dispersant Corexit 9500 was mixed with the oils prior to their dispersion in seawater, the fingerprints of each oil changed primarily as an increase in fluorescence over an emission band centered on 445 nm. In order to simplify the wealth of information available in the excitation-emission matrix spectra (EEMs), two ratios were calculated. A 66-90% decrease in the slope ratio was observed with the addition of Corexit. When the slope ratios were reduced in complexity to intensity ratios, similar trends were apparent. As a result either of the ratios could be used as a simple and rapid means of identifying and monitoring chemically dispersed oil in the open ocean.

  18. Flash Spectroscopy: Emission Lines From the Ionized Circumstellar Material Around 10-Day-Old Type II Supernovae

    Science.gov (United States)

    Khazov, D.; Yaron, O.; Gal-Yam, A.; Manulis, I.; Rubin, A.; Kulkarni, S. R.; Arcavi, I.; Kasliwal, M. M.; Ofek, E. O.; Cao, Y.; hide

    2016-01-01

    Supernovae (SNe) embedded in dense circumstellar material (CSM) may show prominent emission lines in their early-time spectra (spectroscopy"), we can measure various physical properties of the CSM, as well as the mass-loss rate of the progenitor during the year prior to its explosion. Searching through the Palomar Transient Factory (PTF and iPTF) SN spectroscopy databases from 2009 through 2014, we found 12 SNe II showing flash-ionized (FI) signatures in their first spectra. All are younger than 10 days. These events constitute 14% of all 84 SNe in our sample having a spectrum within 10 days from explosion, and 18% of SNe II observed at ages <5 days, thereby setting lower limits on the fraction of FI events. We classified as "blue/featureless" (BF) those events having a first spectrum that is similar to that of a blackbody, without any emission or absorption signatures. It is possible that some BF events had FI signatures at an earlier phase than observed, or that they lack dense CSM around the progenitor. Within 2 days after explosion, 8 out of 11 SNe in our sample are either BF events or show FI signatures. Interestingly, we found that 19 out of 21 SNe brighter than an absolute magnitude M(sub R) = -18.2 belong to the FI or BF groups, and that all FI events peaked above M(sub R) = -17.6 mag, significantly brighter than average SNe II.

  19. Phosphorus kinetics in ovine fed with different phosphorus sources, using the isotopic dilution technique

    International Nuclear Information System (INIS)

    Vitti, D.M.S.S.; Abdalla, A.L.; Meirelles, C.F.

    1992-01-01

    Phosphorus kinetics in fluids and tissues of sheep was studied. Sixteen castrated sheep were kept in metabolism cages, receiving a semipuried diet containing as phosphorus sources dicalcium phosphate (BIC), monoammonium phosphate (MAP), superphosphate (SPT) and Tapita phosphate (TAP) 200 μCi P-32 was intravenously injected in each sheep and blood and feces were collected for eight days. From the specific activities in feces and plasma the endogenous phosphorus and the absorption coefficient were calculated. plasma P-32 half-life was determined. Nine days after injection the animals were killed and liver, kidney and muscle and bone samples were collected. P-32 retention and specific activities in tissues were determined. Endogenous phosphorus and absorption coefficient values were 54.44 ± 15.31 mh/kg live weight and 0.60; 47.98 ± 12.44 and 0.56; 39.70 ± 7.29 and 0.49; 59.11 ± 17.12 and 0.58 respectively bor BIC, MAP, TAP and SPT. P-32 retention by tissues was 0.29 ± 0.09; 0.27 ± 0.06; 0.16 ± 0.04 and 0.08 ± 0.03 dose/g fresh matter, respectively for bone, liver, kidney and muscle. It was concluded that animals which received TAP showed differences in absorption, distribution and P-32 retention by fluids and tissues. Phosphorus availability was lower for this source. (author)

  20. Estimate of dietary phosphorus intake using 24-h urine collection

    Science.gov (United States)

    Morimoto, Yuuka; Sakuma, Masae; Ohta, Hiroyuki; Suzuki, Akitsu; Matsushita, Asami; Umeda, Minako; Ishikawa, Makoto; Taketani, Yutaka; Takeda, Eiji; Arai, Hidekazu

    2014-01-01

    Increases in serum phosphorus levels and dietary phosphorus intake induces vascular calcification, arterial sclerosis and cardiovascular diseases. Limiting phosphorus intake is advisable, however, no assessment methods are capable of estimating dietary phosphorus intake. We hypothesized that urinary phosphorus excretion can be translated into estimation of dietary phosphorus intake, and we evaluated whether a 24-h urine collection method could estimate dietary phosphorus intake. Thirty two healthy subjects were recruited for this study. Subjects collected urine samples over 24 h and weighed dietary records. We calculated dietary protein intake and phosphorus intake from dietary records and urine collection, and investigated associations between the two methods in estimating protein and phosphorus intake. Significant positive correlations were observed between dietary records and UC for protein and phosphorus intake. The average intakes determined from dietary records were significantly higher than from urine collection for both protein and phosphorus. There was a significant positive correlation between both the phosphorus and protein difference in dietary records and urine collection. The phosphorus-protein ratio in urine collection was significantly higher than in dietary records. Our data indicated that the 24-h urine collection method can estimate the amount of dietary phosphorus intake, and the results were superior to estimation by weighed dietary record. PMID:25120281

  1. Phosphorus run-off assessment in a watershed.

    Science.gov (United States)

    Chebud, Yirgalem; Naja, Ghinwa M; Rivero, Rosanna

    2011-01-01

    The Watershed Assessment Model was used to simulate the runoff volume, peak flows, and non-point source phosphorus loadings from the 5870 km(2) Lake Okeechobee watershed as a case study. The results were compared to on-site monitoring to verify the accuracy of the method and to estimate the observed/simulated error. In 2008, the total simulated phosphorus contribution was 9634, 6524 and 3908 kg (P) y(-1) from sod farms, citrus farms and row crop farmlands, respectively. Although the dairies represent less than 1% of the total area of Kissimmee basin, the simulated P load from the dairies (9283 kg (P) y(-1) in 2008) made up 5.4% of the total P load during 2008. On average, the modeled P yield rates from dairies, sod farms and row crop farmlands are 3.85, 2.01 and 0.86 kg (P) ha(-1) y(-1), respectively. The maximum sediment simulated phosphorus yield rate is about 2 kg (P) ha(-1) and the particulate simulated phosphorus contribution from urban, improved pastures and dairies to the total phosphorus load was estimated at 9%, 3.5%, and 1%, respectively. Land parcels with P oversaturated soil as well as the land parcels with high phosphorus assimilation and high total phosphorus contribution were located. The most critical sub-basin was identified for eventual targeting by enforced agricultural best management practices. Phosphorus load, including stream assimilation, incoming to Lake Okeechobee from two selected dairies was also determined.

  2. Sustainable use of phosphorus: a finite resource.

    Science.gov (United States)

    Scholz, Roland W; Ulrich, Andrea E; Eilittä, Marjatta; Roy, Amit

    2013-09-01

    Phosphorus is an essential element of life and of the modern agricultural system. Today, science, policy, agro-industry and other stakeholder groups are increasingly concerned about the sustainable use of this resource, given the dissipative nature of phosphorus and difficulties in assessing, evaluating, and coping with phosphorus pollution in aquatic and terrestrial systems. We argue that predictions about a forthcoming peak, followed by a quick reduction (i.e., physical phosphate rock scarcity) are unreasoned and stress that access to phosphorus (economic scarcity) is already, and may increasingly become critical, in particular for smallholders farmers in different parts of the world. The paper elaborates on the design, development, goals and cutting-edge contributions of a global transdisciplinary process (i.e. mutual learning between science and society including multiple stakeholders) on the understanding of potential contributions and risks related to the current mode of using phosphorus on multiple scales (Global TraPs). While taking a global and comprehensive view on the whole phosphorus-supply chain, Global TraPs organizes and integrates multiple transdisciplinary case studies to better answer questions which inform sustainable future phosphorus use. Its major goals are to contribute to four issues central to sustainable resource management: i) long-term management of biogeochemical cycles, in particular the challenge of closing the phosphorus cycle, ii) achieving food security, iii) avoiding environmental pollution and iv) sustainability learning on a global level by transdisciplinary processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Towards a closed phosphorus cycle

    NARCIS (Netherlands)

    Keyzer, M.A.

    2010-01-01

    Summary: This paper stresses the need to address upcoming scarcity of phosphorus, a mineral nutrient that is essential for all life on Earth. Agricultural crops obtain phosphorus from the pool in the soil that can be replenished by recycling of organic material, or by application of inorganic

  4. Spatially Resolved HST Grism Spectroscopy of a Lensed Emission Line Galaxy at z ~ 1

    Science.gov (United States)

    Frye, Brenda L.; Hurley, Mairead; Bowen, David V.; Meurer, Gerhardt; Sharon, Keren; Straughn, Amber; Coe, Dan; Broadhurst, Tom; Guhathakurta, Puragra

    2012-07-01

    We take advantage of gravitational lensing amplification by A1689 (z = 0.187) to undertake the first space-based census of emission line galaxies (ELGs) in the field of a massive lensing cluster. Forty-three ELGs are identified to a flux of i 775 = 27.3 via slitless grism spectroscopy. One ELG (at z = 0.7895) is very bright owing to lensing magnification by a factor of ≈4.5. Several Balmer emission lines (ELs) detected from ground-based follow-up spectroscopy signal the onset of a major starburst for this low-mass galaxy (M * ≈ 2 × 109 M ⊙) with a high specific star formation rate (≈20 Gyr-1). From the blue ELs we measure a gas-phase oxygen abundance consistent with solar (12+log(O/H) = 8.8 ± 0.2). We break the continuous line-emitting region of this giant arc into seven ~1 kpc bins (intrinsic size) and measure a variety of metallicity-dependent line ratios. A weak trend of increasing metal fraction is seen toward the dynamical center of the galaxy. Interestingly, the metal line ratios in a region offset from the center by ~1 kpc have a placement on the blue H II region excitation diagram with f ([O III])/f (Hβ) and f ([Ne III])/f (Hβ) that can be fitted by an active galactic nucleus (AGN). This asymmetrical AGN-like behavior is interpreted as a product of shocks in the direction of the galaxy's extended tail, possibly instigated by a recent galaxy interaction. Based, in part, on data obtained with the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA, and was made possible by the generous financial support of the W. M. Keck Foundation.

  5. Improvement of AOAC Official Method 984.27 for the determination of nine nutritional elements in food products by Inductively coupled plasma-atomic emission spectroscopy after microwave digestion: single-laboratory validation and ring trial.

    Science.gov (United States)

    Poitevin, Eric; Nicolas, Marine; Graveleau, Laetitia; Richoz, Janique; Andrey, Daniel; Monard, Florence

    2009-01-01

    A single-laboratory validation (SLV) and a ring trial (RT) were undertaken to determine nine nutritional elements in food products by inductively coupled plasma-atomic emission spectroscopy in order to improve and update AOAC Official Method 984.27. The improvements involved optimized microwave digestion, selected analytical lines, internal standardization, and ion buffering. Simultaneous determination of nine elements (calcium, copper, iron, potassium, magnesium, manganese, sodium, phosphorus, and zinc) was made in food products. Sample digestion was performed through wet digestion of food samples by microwave technology with either closed or open vessel systems. Validation was performed to characterize the method for selectivity, sensitivity, linearity, accuracy, precision, recovery, ruggedness, and uncertainty. The robustness and efficiency of this method was proved through a successful internal RT using experienced food industry laboratories. Performance characteristics are reported for 13 certified and in-house reference materials, populating the AOAC triangle food sectors, which fulfilled AOAC criteria and recommendations for accuracy (trueness, recovery, and z-scores) and precision (repeatability and reproducibility RSD and HorRat values) regarding SLV and RT. This multielemental method is cost-efficient, time-saving, accurate, and fit-for-purpose according to ISO 17025 Norm and AOAC acceptability criteria, and is proposed as an improved version of AOAC Official Method 984.27 for fortified food products, including infant formula.

  6. To the application of the emission Mössbauer and positron annihilation spectroscopies for detection of carcinogens

    Science.gov (United States)

    Bokov, A. V.; Byakov, V. M.; Kulikov, L. A.; Perfiliev, Yu. D.; Stepanov, S. V.

    2017-11-01

    Being the main cause of cancer, almost all chemical carcinogens are strong electrophiles, that is, they have a high affinity for the electron. We have shown that positron annihilation lifetime spectroscopy (PALS) is able to detect chemical carcinogens by their inhibition of positronium (Ps) formation in liquid media. Electrophilic carcinogens intercept thermalized track electrons, which are precursors of Ps, and as a result, when they are present Ps atom does not practically form. Available biophysical data seemingly indicate that frozen solutions model better an intracellular medium than the liquid ones. So it is reasonable to use emission Mössbauer spectroscopy (EMS) to detect chemical carcinogens, measuring the yield of 57Fe2+ions formed in reactions of Auger electrons and other secondary electrons they produced with 57Fe3+. These reactions are similar to the Ps formation process in the terminal part the positron track: e++ e- =>Ps. So EMS and PALS are complementary methods for detection of carcinogenic compounds.

  7. Transformation of apatite phosphorus and non-apatite inorganic phosphorus during incineration of sewage sludge.

    Science.gov (United States)

    Li, Rundong; Zhang, Ziheng; Li, Yanlong; Teng, Wenchao; Wang, Weiyun; Yang, Tianhua

    2015-12-01

    The recovery of phosphorus from incinerated sewage sludge ash (SSA) is assumed to be economical. Transformation from non-apatite inorganic phosphorus (NAIP) to apatite phosphorus (AP), which has a higher bioavailability and more extensive industrial applications, was studied at 750-950°C by sewage sludge incineration and model compound incineration with a calcium oxide (CaO) additive. Thermogravimetric differential scanning calorimetry analysis and X-ray diffraction measurements were used to analyze the reactions between NAIP with CaO and crystallized phases in SSA. High temperatures stimulated the volatilization of NAIP instead of AP. Sewage sludge incineration with CaO transformed NAIP into AP, and the percentage of AP from the total phosphorus reached 99% at 950°C. Aluminum phosphate reacted with CaO, forming Ca2P2O7 and Ca3(PO4)2 at 750-950°C. Reactions between iron phosphate and CaO occurred at lower temperatures, forming Ca(PO3)2 before reaching 850°C. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. The New Nordic Diet: phosphorus content and absorption.

    Science.gov (United States)

    Salomo, Louise; Poulsen, Sanne K; Rix, Marianne; Kamper, Anne-Lise; Larsen, Thomas M; Astrup, Arne

    2016-04-01

    High phosphorus content in the diet may have adverse effect on cardiovascular health. We investigated whether the New Nordic Diet (NND), based mainly on local, organic and less processed food and large amounts of fruit, vegetables, wholegrain and fish, versus an Average Danish Diet (ADD) would reduce the phosphorus load due to less phosphorus-containing food additives, animal protein and more plant-based proteins. Phosphorus and creatinine were measured in plasma and urine at baseline, week 12 and week 26 in 132 centrally obese subjects with normal renal function as part of a post hoc analysis of data acquired from a 26-week controlled trial. We used the fractional phosphorus excretion as a measurement of phosphorus absorption. Mean baseline fractional phosphorus excretion was 20.9 ± 6.6 % in the NND group (n = 82) and 20.8 ± 5.5 % in the ADD group (n = 50) and was decreased by 2.8 ± 5.1 and 3.1 ± 5.4 %, respectively, (p = 0.6) at week 26. At week 26, the mean change in plasma phosphorus was 0.04 ± 0.12 mmol/L in the NND group and -0.03 ± 0.13 mmol/L in the ADD group (p = 0.001). Mean baseline phosphorus intake was 1950 ± 16 mg/10 MJ in the NND group and 1968 ± 22 mg/10 MJ in the ADD group and decreased less in the NND compared to the ADD (67 ± 36 mg/10 MJ and -266 ± 45 mg/day, respectively, p food concept beneficial regarding phosphorus absorption.

  9. Determination of Cr(VI) and Cr(III) in urine and dextrose by inductively coupled plasma emission spectroscopy

    Science.gov (United States)

    Mianzhi, Zhuang; Barnes, Ramon M.

    The determination of Cr(VI) and Cr(III) in human urine and in commercial dextrose solution is performed by induclively coupled plasma-atomic emission spectroscopy after selective preconcentration of the chromium species at different pH values by poly(dithiocarbamate) and poly(acrylamidoxime) chelating resins. The chelating properties of these resins with chromium, including the kinetics of uptake and removal of Cr(III), and the influence of matrix concentrations were evaluated. Chromium in human urine was found to exist exclusively as Cr(III).

  10. Emission and distribution of phosphine in paddy fields and its relationship with greenhouse gases.

    Science.gov (United States)

    Chen, Weiyi; Niu, Xiaojun; An, Shaorong; Sheng, Hong; Tang, Zhenghua; Yang, Zhiquan; Gu, Xiaohong

    2017-12-01

    Phosphine (PH 3 ), as a gaseous phosphide, plays an important role in the phosphorus cycle in ecosystems. In this study, the emission and distribution of phosphine, carbon dioxide (CO 2 ) and methane (CH 4 ) in paddy fields were investigated to speculate the future potential impacts of enhanced greenhouse effect on phosphorus cycle involved in phosphine by the method of Pearson correlation analysis and multiple linear regression analysis. During the whole period of rice growth, there was a significant positive correlation between CO 2 emission flux and PH 3 emission flux (r=0.592, p=0.026, n=14). Similarly, a significant positive correlation of emission flux was also observed between CH 4 and PH 3 (r=0.563, p=0.036, n=14). The linear regression relationship was determined as [PH 3 ] flux =0.007[CO 2 ] flux +0.063[CH 4 ] flux -4.638. No significant differences were observed for all values of matrix-bound phosphine (MBP), soil carbon dioxide (SCO 2 ), and soil methane (SCH 4 ) in paddy soils. However, there was a significant positive correlation between MBP and SCO 2 at heading, flowering and ripening stage. The correlation coefficients were 0.909, 0.890 and 0.827, respectively. In vertical distribution, MBP had the analogical variation trend with SCO 2 and SCH 4 . Through Pearson correlation analysis and multiple stepwise linear regression analysis, pH, redox potential (Eh), total phosphorus (TP) and acid phosphatase (ACP) were identified as the principal factors affecting MBP levels, with correlative rankings of Eh>pH>TP>ACP. The multiple stepwise regression model ([MBP]=0.456∗[ACP]+0.235∗[TP]-1.458∗[Eh]-36.547∗[pH]+352.298) was obtained. The findings in this study hold great reference values to the global biogeochemical cycling of phosphorus in the future. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Adaptive Evolution of Phosphorus Metabolism in Prochlorococcus

    DEFF Research Database (Denmark)

    Casey, John R; Mardinoglu, Adil; Nielsen, Jens

    2016-01-01

    Inorganic phosphorus is scarce in the eastern Mediterranean Sea, where the high-light-adapted ecotype HLI of the marine picocyanobacterium Prochlorococcus marinus thrives. Physiological and regulatory control of phosphorus acquisition and partitioning has been observed in HLI both in culture...... and in the field; however, the optimization of phosphorus metabolism and associated gains for its phosphorus-limited-growth (PLG) phenotype have not been studied. Here, we reconstructed a genome-scale metabolic network of the HLI axenic strain MED4 (iJC568), consisting of 568 metabolic genes in relation to 794...... through drastic depletion of phosphorus-containing biomass components but also through network-wide reductions in phosphate-reaction participation and the loss of a key enzyme, succinate dehydrogenase. These alterations occur despite the stringency of having relatively few pathway redundancies...

  12. Direct determination of energy level alignment and charge transport at metal-Alq3 interfaces via ballistic-electron-emission spectroscopy.

    Science.gov (United States)

    Jiang, J S; Pearson, J E; Bader, S D

    2011-04-15

    Using ballistic-electron-emission spectroscopy (BEES), we directly determined the energy barrier for electron injection at clean interfaces of Alq(3) with Al and Fe to be 2.1 and 2.2 eV, respectively. We quantitatively modeled the sub-barrier BEES spectra with an accumulated space charge layer, and found that the transport of nonballistic electrons is consistent with random hopping over the injection barrier.

  13. Phosphorus effect on fracture properties of structural steels

    International Nuclear Information System (INIS)

    Goritskij, V.M.; Guseva, I.A.

    1985-01-01

    Phosphorus content is studied for its effect on fracture peculiarities and fracture toughness. It is supposed that the phosphorus effect on ductile fractures is associated with phosphorus segregation on the ferrite-carbide interfaces. An increase of the phosphorus content in heat-treated 10KhSND steel from 0.020 up to 0.043 wt.% results in a decrease of the pore size and asub(p) value. Close linear correlation is established between critical temperature of embrittlement T 50 and √ asub(p) or √ KC values for a number of structural steels with different phosphorus content

  14. Tomography feasibility study on the optical emission spectroscopy diagnostic for the negative ion source of the ELISE test facility

    International Nuclear Information System (INIS)

    Bonomo, F; Agostini, M; Brombin, M; Pasqualotto, R; Fantz, U; Franzen, P; Wünderlich, D

    2014-01-01

    A feasibility study of a spectroscopic tomographic diagnostic for the emissivity reconstruction of the plasma parameters in the large negative ion source of the test facility ELISE is described. Tomographic tools are developed to be applied to the measurements of the ELISE optical emission spectroscopy (OES) diagnostic, in order to reconstruct the emissivity distribution from hydrogen (or deuterium) plasma close to the plasma grid, where negative ions are produced and extracted to be accelerated. Various emissivity phantoms, both symmetric and asymmetric, reproducing different plasma experimental conditions have been simulated to test the tomographic algorithm. The simultaneous algebraic reconstruction technique has been applied, accounting for the OES geometrical layout together with a suitable pixel representation. Even with a limited number of 14 lines of sight (LoSs), the plasma emissivity distribution expected on the ELISE source can be successfully reconstructed. In particular, asymmetries in the emissivity pattern can be detected and reproduced with low errors. A systematic investigation of different geometrical layouts of the LoSs as well as of the pixel arrangements has been carried out, and a final configuration has been identified. Noise on the simulated experimental spectroscopic measurements has been tested, confirming the reliability of the adopted tomographic tools for the plasma emissivity reconstructions of the source plasma in ELISE with the actual OES diagnostic system. (paper)

  15. Sustainable Phosphorus Chemistry: A Silylphosphide Synthon for the Generation of Value-Added Phosphorus Chemicals.

    Science.gov (United States)

    Slootweg, J Chris

    2018-05-07

    Avoiding white phosphorus: Cummins and Geeson have recently described the conversion of phosphoric acid into the novel bis(trichlorosilyl)phosphide anion, which serves as a key intermediate in the synthesis of organophosphines, hexafluorophosphate, and phosphine gas in a reaction sequence that does not rely on white phosphorus. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Electric Conductivity of Phosphorus Nanowires

    International Nuclear Information System (INIS)

    Jing-Xiang, Zhang; Hui, Li; Xue-Qing, Zhang; Kim-Meow, Liew

    2009-01-01

    We present the structures and electrical transport properties of nanowires made from different strands of phosphorus chains encapsulated in carbon nanotubes. Optimized by density function theory, our results indicate that the conductance spectra reveal an oscillation dependence on the size of wires. It can be seen from the density of states and current-voltage curves that the structure of nanowires affects their properties greatly. Among them, the DNA-like double-helical phosphorus nanowire exhibits the distinct characteristic of an approximately linear I – V relationship and has a higher conductance than others. The transport properties of phosphorus nanowires are highly correlated with their microstructures. (condensed matter: structure, mechanical and thermal properties)

  17. Spectroscopy and reactions of vibrationally excited transient molecules

    Energy Technology Data Exchange (ETDEWEB)

    Dai, H.L. [Univ. of Pennsylvania, Philadelphia (United States)

    1993-12-01

    Spectroscopy, energy transfer and reactions of vibrationally excited transient molecules are studied through a combination of laser-based excitation techniques and efficient detection of emission from the energized molecules with frequency and time resolution. Specifically, a Time-resolved Fourier Transform Emission Spectroscopy technique has been developed for detecting dispersed laser-induced fluorescence in the IR, visible and UV regions. The structure and spectroscopy of the excited vibrational levels in the electronic ground state, as well as energy relaxation and reactions induced by specific vibronic excitations of a transient molecule can be characterized from time-resolved dispersed fluorescence in the visible and UV region. IR emissions from highly vibrational excited levels, on the other hand, reveal the pathways and rates of collision induced vibrational energy transfer.

  18. Magnetic resonance spectroscopy studies in migraine

    Energy Technology Data Exchange (ETDEWEB)

    Montagna, P.; Cortelli, P.; Barbiroli, B. (Inst. of Medical Pathology, Univ. of Bologna (Italy))

    1994-06-01

    The authors describe the method of [sup 31]phosphorus magnetic resonance spectroscopy and review the results when it is applied to the study of brain and muscle energy metabolism in migraine subjects. Brain energy metabolism appears to be abnormal in all major subtypes of migraine when measured both during and between attacks. Impaired energy metabolism is also documented in skeletal muscle. It is suggested that migraine is associated with a generalized disorder of mitochondrial oxidative phosphorylation and that this may constitute a threshold for the triggering of migraine attacks. 47 refs., 10 figs., 3 tabs.

  19. Admittance spectroscopy or deep level transient spectroscopy: A contrasting juxtaposition

    Science.gov (United States)

    Bollmann, Joachim; Venter, Andre

    2018-04-01

    A comprehensive understanding of defects in semiconductors remains of primary importance. In this paper the effectiveness of two of the most commonly used semiconductor defect spectroscopy techniques, viz. deep level transient spectroscopy (DLTS) and admittance spectroscopy (AS) are reviewed. The analysis of defects present in commercially available SiC diodes shows that admittance spectroscopy allows the identification of deep traps with reduced measurement effort compared to deep Level Transient Spectroscopy (DLTS). Besides the N-donor, well-studied intrinsic defects were detected in these diodes. Determination of their activation energy and defect density, using the two techniques, confirm that the sensitivity of AS is comparable to that of DLTS while, due to its well defined peak shape, the spectroscopic resolution is superior. Additionally, admittance spectroscopy can analyze faster emission processes which make the study of shallow defects more practical and even that of shallow dopant levels, possible. A comparative summary for the relevant spectroscopic features of the two capacitance methods are presented.

  20. Production of carrier-free phosphorus-33 at MURR

    International Nuclear Information System (INIS)

    Jia, W.; Ketring, A.R.; Schuh, J.; Lanigan, J.; Ma, D.; Manson, L.; Chanley, D.

    1996-01-01

    Phosphorus-33, a new radionuclide used in medical and biochemical research, is produced at the University of Missouri research reactor (MURR) in production quantities. Phosphorus-33 has a longer shelf life and lower dose rates than phosphorus-32. Recently, the MURR and New England Nuclear (NEN) jointly developed a method to recover carrier-free phosphorus-33 as well as the enriched sulfur target using a sublimation technique at reduced pressure

  1. Volcanic SO2 and SiF4 visualization using 2-D thermal emission spectroscopy – Part 1: Slant-columns and their ratios

    Directory of Open Access Journals (Sweden)

    M. Grutter

    2012-02-01

    Full Text Available The composition and emission rates of volcanic gas plumes provide insight of the geologic internal activity, atmospheric chemistry, aerosol formation and radiative processes around it. Observations are necessary for public security and the aviation industry. Ground-based thermal emission infrared spectroscopy, which uses the radiation of the volcanic gas itself, allows for continuously monitoring during day and night from a safe distance. We present measurements on Popocatépetl volcano based on thermal emission spectroscopy during different campaigns between 2006–2009 using a Scanning Infrared Gas Imaging System (SIGIS. The experimental set-up, measurement geometries and analytical algorithms are described. The equipment was operated from a safe distance of 12 km from the volcano at two different spectral resolutions: 0.5 and 4 cm−1. The 2-dimensional scanning capability of the instrument allows for an on-line visualization of the volcanic SO2 plume and its animation. SiF4 was also identified in the infrared spectra recorded at both resolutions. The SiF4/SO2 molecular ratio can be calculated from each image and used as a highly useful parameter to follow changes in volcanic activity. A small Vulcanian eruption was monitored during the night of 16 to 17 November 2008 and strong ash emission together with a pronounced SO2 cloud was registered around 01:00 a.m. LST (Local Standard Time. Enhanced SiF4/SO2 ratios were observed before and after the eruption. A validation of the results from thermal emission measurements with those from absorption spectra of the moon taken at the same time, as well as an error analysis, are presented. The inferred propagation speed from sequential images is used in a subsequent paper (Part 2 to calculate the emission rates at different distances from the crater.

  2. Study of the trace tritium content in deuterium plasmas of the JET tokamak based on neutron emission spectroscopy measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ringmar, David

    2001-02-01

    This thesis describes a study of the evolution of the trace tritium content in the JET tokamak. The study is based on measurements of the neutron emission, which were performed with the magnetic proton recoil (MPR) spectrometer. Data analysis procedures used to extract the results are described in some detail. The thesis also describes a simplified theoretical model to calculate the absolute tritium concentration with a comparison to the experimental results. The present study covers the time period 1996-2000 and the evolution of neutron emission spectroscopy (NES) results are compared with information from related diagnostic sources, and used to discuss the important issue of how tritium is retained in the JET tokamak.

  3. Study of the trace tritium content in deuterium plasmas of the JET tokamak based on neutron emission spectroscopy measurements

    International Nuclear Information System (INIS)

    Ringmar, David

    2001-02-01

    This thesis describes a study of the evolution of the trace tritium content in the JET tokamak. The study is based on measurements of the neutron emission, which were performed with the magnetic proton recoil (MPR) spectrometer. Data analysis procedures used to extract the results are described in some detail. The thesis also describes a simplified theoretical model to calculate the absolute tritium concentration with a comparison to the experimental results. The present study covers the time period 1996-2000 and the evolution of neutron emission spectroscopy (NES) results are compared with information from related diagnostic sources, and used to discuss the important issue of how tritium is retained in the JET tokamak

  4. Optical emission spectroscopy at the large RF driven negative ion test facility ELISE: Instrumental setup and first results

    International Nuclear Information System (INIS)

    Wünderlich, D.; Fantz, U.; Franzen, P.; Riedl, R.; Bonomo, F.

    2013-01-01

    One of the main topics to be investigated at the recently launched large (A source = 1.0 × 0.9 m 2 ) ITER relevant RF driven negative ion test facility ELISE (Extraction from a Large Ion Source Experiment) is the connection between the homogeneity of the plasma parameters close to the extraction system and the homogeneity of the extracted negative hydrogen ion beam. While several diagnostics techniques are available for measuring the beam homogeneity, the plasma parameters are determined by optical emission spectroscopy (OES) solely. First OES measurements close to the extraction system show that without magnetic filter field the vertical profile of the plasma emission is more or less symmetric, with maxima of the emission representing the projection of the plasma generation volumes, and a distinct minimum in between. The profile changes with the strength of the magnetic filter field but under all circumstances the plasma emission in ELISE is much more homogeneous compared to the smaller IPP prototype sources. Planned after this successful demonstration of the ELISE OES system is to combine OES with tomography in order to determine locally resolved values for the plasma parameters

  5. Prevalence of phosphorus containing food additives in grocery stores

    Directory of Open Access Journals (Sweden)

    Janeen B. Leon

    2012-06-01

    In conclusion, phosphorus additives are commonly present in groceries and contribute significantly to the phosphorus content of foods. Moreover, phosphorus additive foods are less costly than additive-free foods. As a result, phosphorus additives may be an important contributor to hyperphosphatemia among persons with chronic kidney disease

  6. The Adequacy of Phosphorus Binder Prescriptions Among American Hemodialysis Patients

    Science.gov (United States)

    Huml, Anne M.; Sullivan, Catherine M.; Leon, Janeen B.; Sehgal, Ashwini R.

    2013-01-01

    Because hemodialysis treatment has a limited ability to remove phosphorus, dialysis patients must restrict dietary phosphorus intake and use phosphorus binding medication. Among patients with restricted dietary phosphorus intake (1000 mg/d), phosphorus binders must bind about 250 mg of excess phosphorus per day and among patients with more typical phosphorus intake (1500 mg/d), binders must bind about 750 mg per day. To determine the phosphorus binding capacity of binder prescriptions among American hemodialysis patients, we undertook a cross-sectional study of a random sample of in-center chronic hemodialysis patients. We obtained data for one randomly selected patient from 244 facilities nationwide. About one-third of patients had hyperphosphatemia (serum phosphorus level > 5.5 mg/dL). Among the 224 patients prescribed binders, the mean phosphorus binding capacity was 256 mg/d (SD 143). 59% of prescriptions had insufficient binding capacity for restricted dietary phosphorus intake, and 100% had insufficient binding capacity for typical dietary phosphorus intake. Patients using two binders had a higher binding capacity than patients using one binder (451 vs. 236 mg/d, p phosphorus balance. Use of two binders results in higher binder capacity. Further work is needed to understand the impact of binder prescriptions on mineral balance and metabolism and to determine the value of substantially increasing binder prescriptions. PMID:23013171

  7. Preliminary analysis of phosphorus flow in Hue Citadel.

    Science.gov (United States)

    Anh, T N Q; Harada, H; Fujii, S; Anh, P N; Lieu, P K; Tanaka, S

    2016-01-01

    Characteristics of waste and wastewater management can affect material flows. Our research investigates the management of waste and wastewater in urban areas of developing countries and its effects on phosphorus flow based on a case study in Hue Citadel, Hue, Vietnam. One hundred households were interviewed to gain insight into domestic waste and wastewater management together with secondary data collection. Next, a phosphorus flow model was developed to quantify the phosphorus input and output in the area. The results showed that almost all wastewater generated in Hue Citadel was eventually discharged into water bodies and to the ground/groundwater. This led to most of the phosphorus output flowing into water bodies (41.2 kg P/(ha year)) and ground/groundwater (25.3 kg P/(ha year)). Sewage from the sewer system was the largest source of phosphorus loading into water bodies, while effluent from on-site sanitation systems was responsible for a major portion of phosphorus into the ground/groundwater. This elevated phosphorus loading is a serious issue in considering surface water and groundwater protection.

  8. Isotopic techniques to study phosphorus cycling in soils

    International Nuclear Information System (INIS)

    Manjaiah, K.M.; Sreenivasa Chari, M.; Sachdev, P.; Sachdev, M.S.

    2008-01-01

    A sound understanding of phosphorus cycling in soil system is essential in order to manage this system in a sustainable manner. Phosphorus transformations are characterized by physico-chemical (sorption-desorption) and biological processes . The transformation rates need to be taken into account while developing nutrient management strategies for economical and sustainable production. One of the important tools and the method gaining popularity for determining the gross transformation rates of nutrients in the soil is the isotopic dilution technique. The major processes in the soil-plant system which determine the distribution and bioavailability of phosphorus in various inorganic and organic soil components consist of: (1) the dissolution of soil mineral phosphates, (2) retention of phosphorus by inorganic soil constituents, (3) decomposition of organic phosphorus contained in plant, animal and microbial detritus and (4) Immobilization of phosphorus via the soil microbial biomass and plan uptake

  9. Characterization of phosphorus forms in lake macrophytes and algae by solution (31)P nuclear magnetic resonance spectroscopy.

    Science.gov (United States)

    Feng, Weiying; Zhu, Yuanrong; Wu, Fengchang; Meng, Wei; Giesy, John P; He, Zhongqi; Song, Lirong; Fan, Mingle

    2016-04-01

    Debris from aquatic macrophytes and algae are important recycling sources of phosphorus (P), which can result in continuing blooms of algae by recycling bioavailable P in the eutrophic lakes. However, knowledge of forms of P in aquatic macrophytes and algae and their contribution to internal loads of P in lakes is limited. Without such knowledge, it is difficult to develop appropriate strategies to remediate and or restore aquatic ecosystems that have become eutrophic. Therefore, in this work, P was extracted from six types of aquatic macrophytes and algae collected from Tai Lake of China and characterized by use of solution (31)P-nuclear magnetic resonance (NMR) spectroscopy. When extracted by 0.5 M NaOH-25 mM EDTA, extraction recovery of total P(TP) and organic P(Po) exceeded 90 %. Concentrations of Po in algae and aquatic macrophytes were 5552 mg kg(-1) and 1005 mg kg(-1) and accounted for 56.0 and 47.2 % of TP, respectively. When Po, including condensed P, was characterized by solution (31)P-NMR Po in algae included orthophosphate monoesters (79.8 %), pyrophosphate (18.2 %), and orthophosphate diester (2.0 %), and Po in aquatic macrophytes included orthophosphate monoesters (90.3 %), pyrophosphate (4.2 %), and orthophosphate diester (5.5 %). Additionally, orthophosphate monoesters in algal debris mainly included β-glycerophosphate (44.1 %), α-glycerophosphate (13.5 %), and glucose 6-phosphate (13.5 %). Orthophosphate monoesters in aquatic macrophytes mainly included β-glycerophosphate (27.9 %), α-glycerophosphate (24.6 %), and adenosine 5' monophosphate (8.2 %). Results derived from this study will be useful in better understanding nutrient cycling, relevant eutrophication processes, and pollution control for freshwater lakes.

  10. Nondestructive determination of nutritional information in oilseed rape leaves using visible/near infrared spectroscopy and multivariate calibrations

    NARCIS (Netherlands)

    Liu Fei, [No Value; Nie PengCheng, [No Value; Huang Min, [No Value; Kong WenWen, [No Value; He Yong, [No Value

    Nitrogen, phosphorus and potassium content are the three most important nutritional parameters for growing oilseed rape. We investigated visible and near infrared (Vis/NIR) spectroscopy combined with chemometrics for the fast and nondestructive determination of nutritional information in oilseed

  11. Photoacoustic and photothermal spectroscopies

    International Nuclear Information System (INIS)

    Sawada, Tsuguo; Kitamori, Takehiko; Nakamura, Masato

    1995-01-01

    Photoacoustic and photothermal spectroscopy methods can be effectively applied to the analysis of microparticles in condensed matter. A more violent photothermal conversion phenomenon of a particle, laser breakdown and accompanying plasma and acoustic emission, was applied to individual detection and analysis of ultrafine particles in ultrapure water. Laser-like nonlinear emission from the plasma was observed. (author)

  12. Spectroscopy Division: progress report for January 1989-December 1989

    International Nuclear Information System (INIS)

    Sharma, A.; Marathe, S.M.

    1990-01-01

    Research and development activities of the Spectroscopy Division during the calendar year 1989 are reported in the form of individual summaries which are grouped under the headings entitled: (i)analysis by optical emission spectroscopy, inductively coupled plasma atomic emission spectrometry and x-ray fluroescence techniques, (ii)atomic, molecular, solid state and laser-spectroscopy, (iii)optics and thin films, (iv)electronics, (v)fabrication, (vi)publications, and (vii)other academic activities. A divisional staff chart is given at the end. (author). figs., tabs

  13. PH Measurements of the Brain Using Phosphorus Magnetic Resonance Spectroscopy (31PMRS) in Healthy Men – Comparison of Two Analysis Methods

    International Nuclear Information System (INIS)

    Cichocka, Monika; Kozub, Justyna; Urbanik, Andrzej

    2015-01-01

    Intracellular pH provides information on homeostatic mechanisms in neurons and glial cells. The aim of this study was to define pH of the brain of male volunteers using phosphorus magnetic resonance spectroscopy ( 31 PMRS) and to compare two methods of calculating this value. In this study, 35 healthy, young, male volunteers (mean age: 25 years) were examined by 31 PMRS in 1.5 T MR system (Signa Excite, GE). The FID CSI (Free Induction Decay Chemical Shift Imaging) sequence was used with the following parameters: TR=4000 ms, FA=90°, NEX=2. Volume of interest (VOI) was selected depending on the size of the volunteers’ brain (11–14 cm 3 , mean 11.53 cm 3 ). Raw data were analyzed using SAGE (GE) software. Based on the chemical shift of peaks in the 31 PMRS spectrum, intracellular pH was calculated using two equations. In both methods the mean pH was slightly alkaline (7.07 and 7.08). Results were compared with a t-test. Significant difference (p<0.05) was found between these two methods. The 31 PMRS method enables non-invasive in vivo measurements of pH. The choice of the calculation method is crucial for computing this value. Comparing the results obtained by different teams can be done in a fully credible way only if the calculations were performed using the same formula

  14. ESR studies of high-energy phosphorus-ion implanted synthetic diamond crystals

    Energy Technology Data Exchange (ETDEWEB)

    Isoya, J [University of Library and Information Science, Tsukuba, Ibaraki (Japan); Kanda, H; Morita, Y; Ohshima, T

    1997-03-01

    Phosphorus is among potential n-type dopants in diamond. High pressure synthetic diamond crystals of type IIa implanted with high energy (9-18 MeV) phosphorus ions have been studied by using electron spin resonance (ESR) technique. The intensity and the linewidth of the ESR signal attributed to the dangling bond of the amorphous phase varied with the implantation dose, suggesting the nature of the amorphization varies with the dose. The ESR signals of point defects have been observed in the low dose as-implanted crystals and in the high dose crystals annealed at high temperature and at high pressure. (author)

  15. Performance of fertigation technique for phosphorus application in cotton

    Directory of Open Access Journals (Sweden)

    M. Aslam

    2009-05-01

    Full Text Available Low native soil phosphorus availability coupled with poor utilization of added phosphorus is one of the major constraints limiting the productivity of the crops. With a view of addressing this issue, field studies were conducted to compare the relative efficacy of broadcast and fertigation techniques for phosphorus application during 2005-2006 using cotton as a test crop. Two methods of phosphorus application i.e. broadcast and fertigation were evaluated using five levels of P2O5 (0, 30, 45, 60 and 75 kg P2O5 ha -1. Fertigation showed an edge over broadcast method at all levels of phosphorus application. The highest seed cotton yield was recorded with 75 kg P2O5 ha-1. Fertilizer phosphorus applied at the rate of 60 kg ha-1 through fertigation produced 3.4 tons ha-1 of seed cotton yield, which was statistically identical to 3.3 tons recorded with 75 kg ha-1 of broadcast phosphorus. Agronomic performance of phosphorus was influenced considerably by either method of fertilizer application. The seed cotton yield per kg of fertigation phosphorus was 48% higher than the corresponding broadcast application. The results of these studies showed that fertigation was the most efficient method of phosphorus application compared with the conventional broadcast application of fertilizers.

  16. Reaching ultra low phosphorus concentrations by filtration techniques

    NARCIS (Netherlands)

    Scherrenberg, S.M.

    2011-01-01

    This research deals with tertiary treatment techniques used for the removal of phosphorus from wastewater treatment plant (WWTP) effluent. The main objective of this research is to obtain ultra low total phosphorus (<0.15 mg total phosphorus/L) concentrations by coagulation, flocculation and

  17. Determination of traces of phosphorus using isotope exchange

    International Nuclear Information System (INIS)

    Zeman, A.; Kratzer, K.

    1976-01-01

    A simple and selective radioanalytical method for the determination of phosphorus (0.015 - 5 μg in a 5 ml sample), based on the heterogeneous isotope exchange, has been developed. The sample containing phosphorus is shaken in the presence of molybdate with a standard solution of tetraphenylarsonium molybdophosphate labelled with phosphorus-32 in 1-2 dicloroethan. From the distribution of the activity between the aqueous and organic phases the amount of phosphorus in the sample can be determined. (Authors)

  18. Patient education for phosphorus management in chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Kalantar-Zadeh K

    2013-05-01

    Full Text Available Kamyar Kalantar-ZadehHarold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, University of California Irvine’s School of Medicine, Irvine, CA, USAObjectives: This review explores the challenges and solutions in educating patients with chronic kidney disease (CKD to lower serum phosphorus while avoiding protein insufficiency and hypercalcemia.Methods: A literature search including terms “hyperphosphatemia,” “patient education,” “food fatigue,” “hypercalcemia,” and “phosphorus–protein ratio” was undertaken using PubMed.Results: Hyperphosphatemia is a strong predictor of mortality in advanced CKD and is remediated via diet, phosphorus binders, and dialysis. Dietary counseling should encourage the consumption of foods with the least amount of inorganic or absorbable phosphorus, low phosphorus-to-protein ratios, and adequate protein content, and discourage excessive calcium intake in high-risk patients. Emerging educational initiatives include food labeling using a “traffic light” scheme, motivational interviewing techniques, and the Phosphate Education Program – whereby patients no longer have to memorize the phosphorus content of each individual food component, but only a “phosphorus unit” value for a limited number of food groups. Phosphorus binders are associated with a clear survival advantage in CKD patients, overcome the limitations associated with dietary phosphorus restriction, and permit a more flexible approach to achieving normalization of phosphorus levels.Conclusion: Patient education on phosphorus and calcium management can improve concordance and adherence and empower patients to collaborate actively for optimal control of mineral metabolism.Keywords: hyperphosphatemia, renal diet, phosphorus binders, educational programs, food fatigue, concordance

  19. The phosphorus and the transition metals chemistry

    International Nuclear Information System (INIS)

    Mathey, F.

    1988-01-01

    The 1988 progress report, concerning the Polytechnic School unit (France), which studies the phosphorus and the transition metals chemistry, is presented. The laboratory activities are related to the following topics: the phosporus heterocyclic chemistry, the phosphorus-carbon double bonds chemistry, the new transition metals phosphorus compounds, the phosphonates and their uses. Some practical applications of homogeneous catalysis and new materials synthesis are investigated. The main results obtained are: the discovery of the tetra-phosphafulvalenes, the utilization of a new synthesis method of the phosphorus-carbon double bonds and the stabilization of the α-phosphonyled carbanions by the lithium diisopropylamidourea. The papers, the congress communications and the thesis are also shown [fr

  20. Management of Natural and Added Dietary Phosphorus Burden in Kidney Disease

    Science.gov (United States)

    Cupisti, Adamasco; Kalantar-Zadeh, Kamyar

    2018-01-01

    Phosphorus retention occurs from higher dietary phosphorus intake relative to its renal excretion or dialysis removal. In the gastrointestinal tract the naturally existing organic phosphorus is only partially (~60%) absorbable; however, this absorption varies widely and is lower for plant-based phosphorus including phytate (80%). The latter phosphorus often remains unrecognized by patients and health care professionals, even though it is widely used in contemporary diets, in particular low-cost foods. In a non-enhanced mixed diet, the digestible phosphorus is closely correlated with total protein content, making protein-rich foods a main source of natural phosphorus. Phosphorus burden is more appropriately limited in pre-dialysis patients who are on low protein diets (~0.6 g/kg/day), whereas dialysis patients who require higher protein intake (~1.2 g/kg/day) are subject to a higher dietary phosphorus load. An effective and patient-friendly approach to reduce phosphorus intake without depriving patients of adequate proteins is to educate patients to avoid foods with high phosphorus relative to protein such as egg yolk and those with high amounts of phosphorus-based preservatives such as certain soft drinks and enhanced cheese and meat. Protein-rich foods should be prepared by boiling, which reduces phosphorus as well as sodium and potassium content, or by other types of cooking induced demineralization. The dose of phosphorus-binding therapy should be adjusted separately for the amount and absorbability of phosphorus in each meal. Dietician counselling to address the foregoing aspects of dietary phosphorus management is instrumental for achieving reduction of phosphorus load. PMID:23465504

  1. phosphorus retention data and metadata

    Science.gov (United States)

    phosphorus retention in wetlands data and metadataThis dataset is associated with the following publication:Lane , C., and B. Autrey. Phosphorus retention of forested and emergent marsh depressional wetlands in differing land uses in Florida, USA. Wetlands Ecology and Management. Springer Science and Business Media B.V;Formerly Kluwer Academic Publishers B.V., GERMANY, 24(1): 45-60, (2016).

  2. Time-dependent Autler-Townes spectroscopy

    International Nuclear Information System (INIS)

    Qamar, Sajid; Zhu, S.-Y.; Zubairy, M Suhail

    2003-01-01

    Autler-Townes spontaneous emission spectroscopy is revisited for a time-dependent case. We report the results of spontaneous emission spectra for nonstationary scattered light signals using the definition of the time-dependent physical spectrum. This is a rare example of problems where time-dependent spectra can be calculated exactly

  3. Time-dependent Autler-Townes spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Qamar, Sajid [Institute for Quantum Studies, Department of Physics, Texas A and M University, College Station, TX 77843-4242 (United States); Zhu, S.-Y. [Institute for Quantum Studies, Department of Physics, Texas A and M University, College Station, TX 77843-4242 (United States); Zubairy, M Suhail [Institute for Quantum Studies, Department of Physics, Texas A and M University, College Station, TX 77843-4242 (United States)

    2003-04-01

    Autler-Townes spontaneous emission spectroscopy is revisited for a time-dependent case. We report the results of spontaneous emission spectra for nonstationary scattered light signals using the definition of the time-dependent physical spectrum. This is a rare example of problems where time-dependent spectra can be calculated exactly.

  4. Assessing the long term impact of phosphorus fertilization on phosphorus loadings using AnnAGNPS.

    Science.gov (United States)

    Yuan, Yongping; Bingner, Ronald L; Locke, Martin A; Stafford, Jim; Theurer, Fred D

    2011-06-01

    High phosphorus (P) loss from agricultural fields has been an environmental concern because of potential water quality problems in streams and lakes. To better understand the process of P loss and evaluate the effects of different phosphorus fertilization rates on phosphorus losses, the USDA Annualized AGricultural Non-Point Source (AnnAGNPS) pollutant loading model was applied to the Ohio Upper Auglaize watershed, located in the southern portion of the Maumee River Basin. In this study, the AnnAGNPS model was calibrated using USGS monitored data; and then the effects of different phosphorus fertilization rates on phosphorus loadings were assessed. It was found that P loadings increase as fertilization rate increases, and long term higher P application would lead to much higher P loadings to the watershed outlet. The P loadings to the watershed outlet have a dramatic change after some time with higher P application rate. This dramatic change of P loading to the watershed outlet indicates that a "critical point" may exist in the soil at which soil P loss to water changes dramatically. Simulations with different initial soil P contents showed that the higher the initial soil P content is, the less time it takes to reach the "critical point" where P loadings to the watershed outlet increases dramatically. More research needs to be done to understand the processes involved in the transfer of P between the various stable, active and labile states in the soil to ensure that the model simulations are accurate. This finding may be useful in setting up future P application and management guidelines.

  5. Quantifying the relative contribution of natural gas fugitive emissions to total methane emissions in Colorado, Utah, and Texas using mobile isotopic methane analysis based on Cavity Ringdown Spectroscopy

    Science.gov (United States)

    Rella, Chris; Winkler, Renato; Sweeney, Colm; Karion, Anna; Petron, Gabrielle; Crosson, Eric

    2014-05-01

    Fugitive emissions of methane into the atmosphere are a major concern facing the natural gas production industry. Because methane is more energy-rich than coal per kg of carbon dioxide emitted into the atmosphere, it represents an attractive alternative to coal for electricity generation, provided that the fugitive emissions of methane are kept under control. A key step in assessing these emissions in a given region is partitioning the observed methane emissions between natural gas fugitive emissions and other sources of methane, such as from landfills or agricultural activities. One effective method for assessing the contribution of these different sources is stable isotope analysis, using the isotopic carbon signature to distinguish between natural gas and landfills or ruminants. We present measurements of methane using a mobile spectroscopic stable isotope analyzer based on cavity ringdown spectroscopy, in three intense natural gas producing regions of the United States: the Denver-Julesburg basin in Colorado, the Uintah basin in Utah, and the Barnett Shale in Texas. Performance of the CRDS isotope analyzer is presented, including precision, calibration, stability, and the potential for measurement bias due to other atmospheric constituents. Mobile isotope measurements of individual sources and in the nocturnal boundary layer have been combined to establish the fraction of the observed methane emissions that can be attributed to natural gas activities. The fraction of total methane emissions in the Denver-Julesburg basin attributed to natural gas emissions is 78 +/- 13%. In the Uinta basin, which has no other significant sources of methane, the fraction is 96% +/- 15%. In addition, results from the Barnett shale are presented, which includes a major urban center (Dallas / Ft. Worth). Methane emissions in this region are spatially highly heterogeneous. Spatially-resolved isotope and concentration measurements are interpreted using a simple emissions model to

  6. Development of a high current 60 keV neutral lithium beam injector for beam emission spectroscopy measurements on fusion experiments

    Science.gov (United States)

    Anda, G.; Dunai, D.; Lampert, M.; Krizsanóczi, T.; Németh, J.; Bató, S.; Nam, Y. U.; Hu, G. H.; Zoletnik, S.

    2018-01-01

    A 60 keV neutral lithium beam system was designed and built up for beam emission spectroscopy measurement of edge plasma on the KSTAR and EAST tokamaks. The electron density profile and its fluctuation can be measured using the accelerated lithium beam-based emission spectroscopy system. A thermionic ion source was developed with a SiC heater to emit around 4-5 mA ion current from a 14 mm diameter surface. The ion optic is following the 2 step design used on other devices with small modifications to reach about 2-3 cm beam diameter in the plasma at about 4 m from the ion source. A newly developed recirculating sodium vapour neutralizer neutralizes the accelerated ion beam at around 260-280 °C even during long (manipulation techniques are applied to allow optimization, aiming, cleaning, and beam modulation. The maximum 60 keV beam energy with 4 mA ion current was successfully reached at KSTAR and at EAST. Combined with an efficient observation system, the Li-beam diagnostic enables the measurement of the density profile and fluctuations on the plasma turbulence time scale.

  7. Atomic emission spectroscopy for the on-line monitoring of incineration processes

    International Nuclear Information System (INIS)

    Timmermans, E.A.H.; Groote, F.P.J. de; Jonkers, J.; Gamero, A.; Sola, A.; Mullen, J.J.A.M. van der

    2003-01-01

    A diagnostic measurement system based on atomic emission spectroscopy has been developed for the purpose of on-line monitoring of hazardous elements in industrial combustion gases. The aim was to construct a setup with a high durability for rough and variable experimental conditions, e.g. a strongly fluctuating gas composition, a high gas temperature and the presence of fly ash and corrosive effluents. Since the setup is primarily intended for the analysis of combustion gases with extremely high concentrations of pollutants, not much effort has been made to achieve low detection limits. It was found that an inductively coupled argon plasma was too sensitive to molecular gas introduction. Therefore, a microwave induced plasma torch, compromising both the demands of a high durability and an effective evaporation and excitation of the analyte was used as excitation source. The analysis system has been installed at an industrial hazardous waste incinerator and successfully tested on combustion gases present above the incineration process. Abundant elements as zinc, lead and sodium could be easily monitored

  8. Ballistic Electron Emission Microscopy/Spectroscopy on Au/Titanylphthalocyanine/GaAs Heterostructures

    International Nuclear Information System (INIS)

    Oezcan, S; Roch, T; Strasser, G; Smoliner, J; Franke, R; Fritz, T

    2007-01-01

    In this article Au/titanylphthalocyanine/GaAs diodes incorporating ultra smooth thin films of the archetypal organic semiconductor titanylphthalocyanine (TiOPc) were investigated by Ballistic Electron Emission Microscopy/Spectroscopy (BEEM/S). Analyzing the BEEM spectra, we find that the TiOPc increases the BEEM threshold voltage compared to reference Au/GaAs diodes. From BEEM images taken we conclude that our molecular beam epitaxial (MBE) grown samples show very homogeneous transmission, compare to wet chemically manufactured organic films. The barrier height measured on the Au- TiOPc-GaAs is V b ∼ 1.2eV, which is in good agreement with the data found in [T. Nishi, K. Tanai, Y. Cuchi, M. R. Willis, and K. Seki Chem. Phys. Lett., vol. 414, pp. 479-482, 2005.]. The results indicate that TiOPc functions as a p-type semiconductor, which is plausible since the measurements were carried out in air [K. Walzer, T. Toccoli, A. Pallaori, R. Verucchi, T. Fritz, K. Leo, A. Boschetti, and S. Iannotte Surf. Scie., vol. 573, pp. 346-358, 2004

  9. X-ray Emission Line Spectroscopy of Nearby Galaxies

    Science.gov (United States)

    Wang, Daniel

    What are the origins of the diffuse soft X-ray emission from non-AGN galaxies? Preliminary analysis of XMM-Newton RGS spectra shows that a substantial fraction of the emission cannot arise from optically-thin thermal plasma, as commonly assumed, and may originate in charge exchange at the interface with neutral gas. We request the support for a comprehensive observing, data analysis, and modeling program to spectroscopically determine the origins of the emission. First, we will use our scheduled XMM-Newton AO-10 368 ks observations of the nearest compact elliptical galaxy M32 to obtain the first spectroscopic calibration of the cumulative soft X-ray emission from the old stellar population and will develop a spectral model for the charge exchange, as well as analysis tools to measure the spatial and kinematic properties of the X-ray line- emitting plasma. Second, we will characterize the truly diffuse emission from the hot plasma and/or its interplay with the neutral gas in a sample of galactic spheroids and active star forming/starburst regions in nearby galaxies observed by XMM-Newton. In particular, we will map out the spatial distributions of key emission lines and measure (or tightly constrain) the kinematics of hot plasma outflows for a few X-ray-emitting regions with high-quality RGS data. For galaxies with insufficient counting statistics in individual emission lines, we will conduct a spectral stacking analysis to constrain the average properties of the X-ray-emitting plasma. We will use the results of these X-ray spectroscopic analyses, together with complementary X-ray CCD imaging/spectral data and observations in other wavelength bands, to test the models of the emission. In addition to the charge exchange, alternative scenarios such as resonance scattering and relic AGN photo-ionization will also be examined for suitable regions. These studies are important to the understanding of the relationship between the diffuse soft X-ray emission and various

  10. Quantitative analysis of phosphosilicate glass films on silicon wafers for calibration of x-ray fluorescence spectrometry standards

    International Nuclear Information System (INIS)

    Weissman, S.H.

    1983-01-01

    The phosphorus and silicon contents of phosphosilicate glass films deposited by chemical vapor deposition (CVD) on silicon wafers were determined. These films were prepared for use as x-ray fluorescence (XRF) spectrometry standards. The thin films were removed from the wafer by etching with dilute hydrofluoric acid, and the P and Si concentrations in solution were determined by inductively coupled plasma atomic emission spectroscopy (ICP). The calculated phosphorus concentration ranged from 2.2 to 12 wt %, with an uncertainty of 2.73 to 10.1 relative percent. Variation between the calculated weight loss (summation of P 2 O 5 and SiO 2 amounts as determined by ICP) and the measured weight loss (determined gravimetrically) averaged 4.9%. Results from the ICP method, Fourier transform-infrared spectroscopy (FT-IR), dispersive infrared spectroscopy, electron microprobe, and x-ray fluorescence spectroscopy for the same samples are compared

  11. Sub-microanalysis of solid samples with near-field enhanced atomic emission spectroscopy

    Science.gov (United States)

    Wang, Xiaohua; Liang, Zhisen; Meng, Yifan; Wang, Tongtong; Hang, Wei; Huang, Benli

    2018-03-01

    A novel approach, which we have chosen to name it as near-field enhanced atomic emission spectroscopy (NFE-AES), was proposed by introducing a scanning tunnelling microscope (STM) system into a laser-induced breakdown spectrometry (LIBS). The near-field enhancement of a laser-illuminated tip was utilized to improve the lateral resolution tremendously. Using the hybrid arrangement, pure metal tablets were analyzed to verify the performance of NFE-AES both in atmosphere and in vacuum. Due to localized surface plasmon resonance (LSPR), the incident electromagnetic field is enhanced and confined at the apex of tip, resulting in sub-micron scale ablation and elemental emission signal. We discovered that the signal-to-noise ratio (SNR) and the spectral resolution obtained in vacuum condition are better than those acquired in atmospheric condition. The quantitative capability of NFE-AES was demonstrated by analyzing Al and Pb in Cu matrix, respectively. Submicron-sized ablation craters were achieved by performing NFE-AES on a Si wafer with an Al film, and the spectroscopic information from a crater of 650 nm diameter was successfully obtained. Due to its advantage of high lateral resolution, NFE-AES imaging of micro-patterned Al lines on an integrated circuit of a SIM card was demonstrated with a sub-micron lateral resolution. These results reveal the potential of the NFE-AES technique in sub-microanalysis of solids, opening an opportunity to map chemical composition at sub-micron scale.

  12. A portable optical emission spectroscopy-cavity ringdown spectroscopy dual-mode plasma spectrometer for measurements of environmentally important trace heavy metals: Initial test with elemental Hg

    Science.gov (United States)

    Sahay, Peeyush; Scherrer, Susan T.; Wang, Chuji

    2012-09-01

    A portable optical emission spectroscopy-cavity ringdown spectroscopy (OES-CRDS) dual-mode plasma spectrometer is described. A compact, low-power, atmospheric argon microwave plasma torch (MPT) is utilized as the emission source when the spectrometer is operating in the OES mode. The same MPT serves as the atomization source for ringdown measurements in the CRDS mode. Initial demonstration of the instrument is carried out by observing OES of multiple elements including mercury (Hg) in the OES mode and by measuring absolute concentrations of Hg in the metastable state 6s6p 3P0 in the CRDS mode, in which a palm-size diode laser operating at a single wavelength 405 nm is incorporated in the spectrometer as the light source. In the OES mode, the detection limit for Hg is determined to be 44 parts per 109 (ppb). A strong radiation trapping effect on emission measurements of Hg at 254 nm is observed when the Hg solution concentration is higher than 50 parts per 106 (ppm). The radiation trapping effect suggests that two different transition lines of Hg at 253.65 nm and 365.01 nm be selected for emission measurements in lower (50 ppm), respectively. In the CRDS mode, the detection limit of Hg in the metastable state 6s6p 3P0 is achieved to be 2.24 parts per 1012 (ppt) when the plasma is operating at 150 W with sample gas flow rate of 480 mL min-1; the detection limit corresponds to 50 ppm in Hg sample solution. Advantage of this novel spectrometer has two-fold, it has a large measurement dynamic range, from a few ppt to hundreds ppm and the CRDS mode can serve as calibration for the OES mode as well as high sensitivity measurements. Measurements of seven other elements, As, Cd, Mn, Ni, P, Pb, and Sr, using the OES mode are also carried out with detection limits of 1100, 33, 30, 144, 576, 94, and 2 ppb, respectively. Matrix effect in the presence of other elements on Hg measurements has been found to increase the detection limit to 131 ppb. These elements in lower

  13. Phosphorus Spectroscopy of Calf Muscles before and after Exercise

    International Nuclear Information System (INIS)

    Wcisło, Bożena; Cichocka, Monika; Urbanik, Andrzej

    2014-01-01

    The aim of this study was to determine 31 PMRS reference spectrum and intracellular pH of calf muscles in the dominant limb of healthy, young, male volunteers before and after intense physical effort. Examinations were performed with a 1.5 T MR system. FID CSI (Free Induction Decay Chemical Shift Imaging) sequence was used with the following parameters: TR=4000 ms, FA=90°, NEX=2 and VOI (Volume Of Interest)=8×8×8 cm 3 (512 cm 3 ) involving in calf muscles. Raw data was preprocessed using SAGE (GE) software. Authors analyzed relative concentrations ratios of selected metabolites: PCr/ATP and PCr/P i . Intracellular pH and relative concentrations ratios of each metabolite (P i , PCr, α-ATP, β-ATP, γ-ATP, ATP) were also calculated relative to the sum of concentrations of all metabolites. Results were compared with a t-test. Based on statistical analysis of results significant differences (p<0.05) were demonstrated for some of the studied metabolites and for intracellular pH. Increase in PCr concentration in relation to the sum of concentrations of all metabolites and to ATP concentration was noted. However, β-ATP, α-ATP and ATP concentrations relative to the sum of concentrations of all metabolites become reduced. Decrease in pH after physical effort was demonstrated. There were no significant differences (p<0.05) in concentrations of remaining metabolites before and after exercise. Increase in PCr concentration relative to P i concentration and decrease of P i and γ-ATP concentration relative to the sum of concentrations of all metabolites were demonstrated. The 31 PMRS method enables assessment of concentrations of phosphorus-containing metabolites as well as intercellular pH before and after exercise. This method is still under examination, but it has already shown promise as a diagnostic tool for the future

  14. Phosphorus sorption-desorption and effects of temperature, pH and salinity on phosphorus sorption in marsh soils from coastal wetlands with different flooding conditions.

    Science.gov (United States)

    Bai, Junhong; Ye, Xiaofei; Jia, Jia; Zhang, Guangliang; Zhao, Qingqing; Cui, Baoshan; Liu, Xinhui

    2017-12-01

    Wetland soils act as a sink or source of phosphorus (P) to the overlaying water due to phosphorus sorption-desorption processes. Litter information is available on sorption and desorption behaviors of phosphorus in coastal wetlands with different flooding conditions. Laboratory experiments were conducted to investigate phosphorus sorption-desorption processes, fractions of adsorbed phosphorus, and the effects of salinity, pH and temperature on phosphorus sorption on soils in tidal-flooding wetlands (TW), freshwater-flooding wetlands (FW) and seasonal-flooding wetlands (SW) in the Yellow River Delta. Our results showed that the freshly adsorbed phosphorus dominantly exists in Occluded-P and Fe/AlP and their percentages increased with increasing phosphorus adsorbed. Phosphorus sorption isotherms could be better described by the modified Langmuir model than by the modified Freundlich model. A binomial equation could be properly used to describe the effects of salinity, pH, and temperature on phosphorus sorption. Phosphorus sorption generally increased with increasing salinity, pH, and temperature at lower ranges, while decreased in excess of some threshold values. The maximum phosphorus sorption capacity (Q max ) was larger for FW soils (256 mg/kg) compared with TW (218 mg/kg) and SW soils (235 mg/kg) (p < 0.05). The percentage of phosphorus desorption (P des ) in the FW soils (7.5-63.5%) was much lower than those in TW (27.7-124.9%) and SW soils (19.2-108.5%). The initial soil organic matter, pH and the exchangeable Al, Fe and Cd contents were important factors influencing P sorption and desorption. The findings of this study indicate that freshwater restoration can contribute to controlling the eutrophication status of water bodies through increasing P sorption. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Emission spectroscopy for coal-fired cyclone furnace diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Wehrmeyer, J.A.; Boll, D.E.; Smith, R. [Vanderbilt University, Nashville, TN (United States). Dept. of Mechanical Engineering

    2003-08-01

    Using a spectrograph and charge-coupled device (CCD) camera, ultraviolet and visible light emission spectra were obtained from a coal-burning electric utility's cyclone furnaces operating at either fuel-rich or fuel-lean conditions. The aim of this effort is to identify light emission signals that can be related to a cyclone furnace's operating condition in order to adjust its air/fuel ratio to minimize pollutant production. Emission spectra at the burner and outlet ends of cyclone furnaces were obtained. Spectra from all cyclone burners show emission lines for the trace elements Li, Na, K, and Rb, as well as the molecular species OH and CaOH. The Ca emission line is detected at the burner end of both the fuel-rich and fuellean cyclone furnaces but is not detected at the outlet ends of either furnace type. Along with the disappearance of Ca is a concomitant increase in the CaOH signal at the outlet end of both types of furnaces. The OH signal strength is in general stronger when viewing at the burner end rather than the exhaust end of both the fuel-rich and fuel-lean cyclone furnaces, probably due to high, non-equilibrium amounts of OH present inside the furnace. Only one molecular species was detected that could be used as a measure of air/fuel ratio: MgOH. It was detected at the burner end of fuel-rich cyclone furnaces but not detected in fuel-lean cyclone furnaces. More direct markers of air/fuel ratio, such as CO and 02 emission, were not detected, probably due to the generally weak nature of molecular emission relative to ambient blackbody emission present in the cyclone furnaces, even at ultraviolet wavelengths.

  16. The study of Phosphorus distribution at Putrajaya Wetland

    Science.gov (United States)

    Mubin Zahari, Nazirul; Malek, Nur Farzana Fasiha Abdul; Fai, Chow Ming; Humaira Haron, Siti; Hafiz Zawawi, Mohd; Nazmi Ismail, Iszmir; Mohamad, Daud; Syamsir, Agusril; Sidek, Lariyah Mohd; Zakwan Ramli, Mohd; Ismail, Norfariza; Zubir Sapian, Ahmad; Noordin, Normaliza; Rahaman, Nurliyana Abdul; Muhamad, Yahzam; Mat Saman, Jarina

    2018-04-01

    This study is concerning phosphorus distribution in Putrajaya Wetland. Phosphorus is one of the important component in nutrients for living things be it aquatic or non – aquatic organisms. Total phosphorus (TP) results will give some information on the trophic status of surface water in water bodies. The focus of this study is to determine the total phosphorus concentration in Putrajaya Wetland which is in the inlet of the wetland then outlet of the wetland (Central Wetland Lake). The water sample is taken from Putrajaya Wetland and the test was conducted in the laboratory. The result from this study shows the results for total phosphorus according to month, sampling station and cells. Lowest total phosphate at the Central Wetland compare with all the wetland arms cells.

  17. In vivo neurochemistry with emission tomography and magnetic resonance spectroscopy: clinical applications

    International Nuclear Information System (INIS)

    Sole, Angelo Del; Gambini, Anna; Falini, Andrea; Lecchi, Michela; Lucignani, Giovanni

    2002-01-01

    The assessment of neurochemical processes in vivo has received much attention in the past decade as techniques such as positron or single photon emission tomography (PET and SPET), and magnetic resonance spectroscopy (MRS) have become more available. With PET and SPET, basic processes, such as blood flow and oxygen or glucose metabolism, can be regionally assessed, along with more specific functions such as the production, release, and reuptake of neurotransmitters and their occupancy of specific receptors. At the same time, MRS can reveal changes in concentration of several hydrogenate compounds in the brain. All these methods have been extensively applied for research in neurology, and some applications have reached the clinical level, namely for the study of degenerative diseases, motor-neuron diseases, movement disorders, cerebrovascular diseases, and epilepsy. This article focuses on the most relevant information that can be obtained with these complementary techniques to help clinicians in the assessment of neurological diseases. (orig.)

  18. In vivo neurochemistry with emission tomography and magnetic resonance spectroscopy: clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Sole, Angelo Del [Azienda Ospedaliera San Paolo e Universita di Milano, 20142 Milan (Italy); Gambini, Anna; Falini, Andrea [IRCCS H San Raffaele e Universita Vita e Salute, 20132 Milan (Italy); Lecchi, Michela [Azienda Ospedaliera L. Sacco e Universita di Milano, 20157 Milan (Italy); Lucignani, Giovanni [Azienda Ospedaliera L. Sacco e Universita di Milano, 20157 Milan (Italy); Universita di Milano, Istituto di Scienze Radiologiche, Cattedra di Medicina Nucleare c/o Ospedale L. Sacco, Via G.B. Grassi, 74, 20157 Milan (Italy)

    2002-10-01

    The assessment of neurochemical processes in vivo has received much attention in the past decade as techniques such as positron or single photon emission tomography (PET and SPET), and magnetic resonance spectroscopy (MRS) have become more available. With PET and SPET, basic processes, such as blood flow and oxygen or glucose metabolism, can be regionally assessed, along with more specific functions such as the production, release, and reuptake of neurotransmitters and their occupancy of specific receptors. At the same time, MRS can reveal changes in concentration of several hydrogenate compounds in the brain. All these methods have been extensively applied for research in neurology, and some applications have reached the clinical level, namely for the study of degenerative diseases, motor-neuron diseases, movement disorders, cerebrovascular diseases, and epilepsy. This article focuses on the most relevant information that can be obtained with these complementary techniques to help clinicians in the assessment of neurological diseases. (orig.)

  19. [Desmoid fibromatosis in absorption infrared spectroscopy, emission spectral analysis and roentgen diffraction recording].

    Science.gov (United States)

    Zejkan, A; Bejcek, Z; Horejs, J; Vrbová, H; Bakosová, M; Macholda, F; Rykl, D

    1989-10-01

    The authors present results of serial quality and quantity microanalyses of bone patterns and dental tissue patterns in patient with desmoid fibromatosis. Methods of absorption spectroscopy, emission spectral analysis and X-ray diffraction analysis with follow-up to x-ray examination are tested. The above mentioned methods function in a on-line system by means of specially adjusted monitor unit which is controlled centrally by the computer processor system. The whole process of measurement is fully automated and the data obtained are recorded processed in the unit data structure classified into index sequence blocks of data. Serial microanalyses offer exact data for the study of structural changes of dental and bone tissues which manifest themselves in order of crystal grid shifts. They prove the fact that microanalyses give new possibilities in detection and interpretation of chemical and structural changes of apatite cell.

  20. Electrical activation of phosphorus in silicon

    International Nuclear Information System (INIS)

    Goh, K.E.J.; Oberbeck, L.; Simmons, M.Y.; Clark, R.G.

    2003-01-01

    Full text: We present studies of phosphorus δ-doping in silicon with a view to determining the degree of electrical activation of the dopants. These results have a direct consequence for the use of phosphorus as a qubit in a silicon-based quantum computer such as that proposed by Kane. Room temperature and 4 K Hall effect measurements are presented for phosphorus δ-doped layers grown in n-type silicon using two different methods. In the first method, the δ-layer was deposited by a phosphorus effusion cell in an MBE chamber. In the second method, the Si surface was dosed with phosphine gas and then annealed to 550 deg C to incorporate P into the substrate. In both methods, the P δ-doped layer was subsequently encapsulated by ∼25 nm of Si grown epitaxially. We discuss the implications of our results on the fabrication of the Kane quantum computer

  1. Recovery of phosphorus from sewerage treatment sludge

    Energy Technology Data Exchange (ETDEWEB)

    Manuilova, Anastasia

    1999-07-01

    This thesis is a review of the current state of technologies for the removal of phosphorus from wastewater and sludge, and the recovery and re-use of phosphorus. It explains the need for phosphorus removal and describes the current removal processes. Focus is given to phosphorus crystallisation processes and to the processes which treat sewage treatment sludges into potential sources of phosphorus. An interesting possibility to recover phosphorus from sewage sludge by use of Psenner fractionation is also discussed. By this method, the following phosphate fractions of technological significance may be distinguished: (1) redox sensitive phosphates, mainly bound to Fe(OH){sub 3}; (2) phosphate adsorbed to surfaces (Al{sub 2}O{sub 3}), exchangeable against OH{sup -}, and alkali-soluble phosphate; (3) phosphate bound to CaCO{sub 3}, MgCO{sub 3} and in apatite; and (4) organically bound phosphate. The basic removal mechanisms, process schemes and treatment results are described. Two experiments with three different types of sludges from Henriksdal wastewater treatment plant in Stockholm were performed in the laboratory. It was shown that the addition of sodium hydroxide or hydrochloric acid cause the significant release of phosphate (about 80%) for all types of sludges. If a whole Psenner fractionation was performed the phosphate release is approximately 100%.

  2. Synthesis and investigation of the structure and chemical properties of acyclic compounds of bicoordinated phosphorus with a phosphorus-carbon (p-p)/sub π/ bond

    International Nuclear Information System (INIS)

    Markovskii, L.N.; Romanenko, V.D.

    1987-01-01

    Five types of reactions of phosphoalkenes can be distinguished according to the nature of the change in the coordination number and valence of the phosphorus atom in the course of chemical conversions. There are: reactions of cyclodimerization, cycloaddition, and 1,2-addition at the P-C double bond; formation of compounds of tricoordinated pentavalent phosphorus; formation of tetracoordinated phosphorus compounds; reactions of functionalization occurring without a change in the valence and coordination number of the phosphorus atom; and reactions of 1,2-elimination, leading to compounds of monocoordinated phosphorus. This paper reviews each of these reactions in detail, using double-resonance hydrogen 1 and phosphorus 31 NMR spectra and analyzing the acquired chemical shift and spin-spin coupling constants, and also demonstrates the complexation of phosphorus with several metals

  3. N-15 analysis by emission spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-12-31

    The stable isotope of nitrogen, N-15, has become widely used as tracer in agriculture, medicine and biology research. The film gives an overview of the sample preparation and analytical procedures followed in the analysis of the nitrogen isotopic composition (14N/15N ratio) by optical emission spectrometry at the Seibersdorf Laboratory. The subsampling of plant material and the several steps of chemical pretreatment such as Kjeldahl digestion, distillation, titration and adjustment of the proper N concentration in the extract are demonstrated. The preparation of the discharge tubes is shown in detail. Final measurement of the 14N/15N ratio is carried out with the NOI-5 and JASCO emission spectrometers

  4. Anthropogenic Nitrogen and Phosphorus Emissions and Related Grey Water Footprints Caused by EU-27′s Crop Production and Consumption

    Directory of Open Access Journals (Sweden)

    Mesfin M. Mekonnen

    2016-01-01

    Full Text Available Water is a prerequisite for life on our planet. Due to climate change and pollution, water availability for agricultural production, industry and households is increasingly put at risk. With agriculture being the largest water user as well as polluter worldwide, we estimate anthropogenic nitrogen and phosphorus emissions to fresh water related to global crop production at a spatial resolution level of 5 by 5 arc min and calculate the grey water footprints (GWF related to EU-27′s crop production. A multiregional input-output model is used to trace the the GWF embodied in the final consumption of crop products by the EU-27. The total GWF related to crop production in the EU-27 in 2007 was 1 × 1012 m3/year. Spain contributed about 40% to this total. Production of cereals (wheat, rice and other cereals take the largest share, accounting for 30% of the GWF, followed by fruits (17%, vegetables (14%, and oil crops (13%. The total agricultural GWF of the EU-27 related to crop consumption was 1830 billion m3/year, which is 3700 m3/year per capita on average. Overall, the EU-27 was able to externalize about 41% of the GWF to the rest of the world through imports of crop products.

  5. The challenge of controlling phosphorus in chronic kidney disease.

    Science.gov (United States)

    Cannata-Andía, Jorge B; Martin, Kevin J

    2016-04-01

    The pathogenesis and management of chronic kidney disease-mineral bone disorders (CKD-MBD) has experienced major changes, but the control of serum phosphorus at all stages of CKD still seems to be a key factor to improve clinical outcomes. High serum phosphorus is the most important uremia-related, non-traditional risk factor associated with vascular calcification in CKD patients and in the general population. Phosphorus may also be one of the key elements linking vascular calcification with low bone turnover. The main hormones and factors that contribute to the kidney regulation of phosphorus and calcium include parathyroid hormone, FGF-23, klotho and 1,25-dihydroxyvitamin D (1,25(OH)2D). Serum phosphorus did not start rising until CKD 3b in contrast with the earlier changes observed with fibroblast growth factor-23 (FGF-23), Klotho, calcitriol and parathyroid hormone (PTH). Despite FGF-23 and PTH having synergic effects regarding phosphorus removal, they have opposite effects on 1,25(OH)2D3. At the same stages of CKD in which phosphorus retention appears to occur, calcium retention also occurs. As phosphorus accumulation is associated with poor outcomes, an important question without a clear answer is at which level-range should serum phosphorus be maintained at different stages of CKD to improve clinical outcomes. There are four main strategies to manage phosphate homeostasis; phosphorus dietary intake, administration of phosphate binder agents, effective control of hyperparathyroidism and to ensure in the CKD 5D setting, an adequate scheme of dialysis. Despite all the available strategies, and the introduction of new phosphate binder agents in the market, controlling serum phosphorus remains challenging, and hyperphosphatemia continues to be extremely common in CKD 5 patients. Furthermore, despite phosphate binding agents having proved to be effective in reducing serum phosphorus, their ultimate effects on clinical outcomes remain controversial. Thus, we still

  6. Optimizing best management practices to control anthropogenic sources of atmospheric phosphorus deposition to inland lakes.

    Science.gov (United States)

    Weiss, Lee; Thé, Jesse; Winter, Jennifer; Gharabaghi, Bahram

    2018-04-18

    Excessive phosphorus loading to inland freshwater lakes around the globe has resulted in nuisance plant growth along the waterfronts, degraded habitat for cold water fisheries, and impaired beaches, marinas and waterfront property. The direct atmospheric deposition of phosphorus can be a significant contributing source to inland lakes. The atmospheric deposition monitoring program for Lake Simcoe, Ontario indicates roughly 20% of the annual total phosphorus load (2010-2014 period) is due to direct atmospheric deposition (both wet and dry deposition) on the lake. This novel study presents a first-time application of the Genetic Algorithm (GA) methodology to optimize the application of best management practices (BMPs) related to agriculture and mobile sources to achieve atmospheric phosphorus reduction targets and restore the ecological health of the lake. The novel methodology takes into account the spatial distribution of the emission sources in the airshed, the complex atmospheric long-range transport and deposition processes, cost and efficiency of the popular management practices and social constraints related to the adoption of BMPs. The optimization scenarios suggest that the optimal overall capital investment of approximately $2M, $4M, and $10M annually can achieve roughly 3, 4 and 5 tonnes reduction in atmospheric P load to the lake, respectively. The exponential trend indicates diminishing returns for the investment beyond roughly $3M per year and that focussing much of this investment in the upwind, nearshore area will significantly impact deposition to the lake. The optimization is based on a combination of the lowest-cost, most-beneficial and socially-acceptable management practices that develops a science-informed promotion of implementation/BMP adoption strategy. The geospatial aspect to the optimization (i.e. proximity and location with respect to the lake) will help land managers to encourage the use of these targeted best practices in areas that

  7. Availability for plants of phosphorus in some virgin peat samples

    Directory of Open Access Journals (Sweden)

    Armi Kaila

    1958-01-01

    Full Text Available The availability to plants of native peat phosphorus was studied by chemical methods and by a pot experiment in which three successive oat crops were grown with peat as the only source of phosphorus. The eight samples were collected from virgin peat lands. They were air-dried and ground. The samples were found to represent three different types of phosphorus condition: the first group contained relatively high amounts of inorganic phosphorus which was fairly easily available; the second group had a very high capacity to fix phosphorus which made its high quantity of inorganic phosphorus difficultly available; the third group was very poor in total and inorganic phosphorus but the latter was easily soluble and available to plants. On the basis of the capacity and intensity factors determined according to the method by Teräsvuori and also on the basis of inorganic phosphorus extractable by water fairly reliable predictions could be made of the mutual order of the samples as phosphorus supplyer to the plants in the pot experiment. In an incubation experiment at 27°C the amounts of organic phosphorus mineralized during the period of four months were in some of the samples quite marked, even 40 mg/l, and in most of the samples they corresponded to 5 to 15 per cent of the organic phosphorus. The amounts of phosphorus taken up by the oat crops under the favourable conditions of the pot experiment varied from 11 to 60 mg/l or from 20 to 120 kg/ha.

  8. Investigation of local thermodynamic equilibrium of laser induced Al2O3–TiC plasma in argon by spatially resolved optical emission spectroscopy

    Directory of Open Access Journals (Sweden)

    K. Alnama

    2016-06-01

    Full Text Available Plasma plume of Al2O3–TiC is generated by third harmonic Q-switched Nd:YAG nanosecond laser. It is characterized using Optical Emission Spectroscopy (OES at different argon background gas pressures 10, 102, 103, 104 and 105 Pa. Spatial evolution of excitation and ionic temperatures is deduced from spectral data analysis. Temporal evolution of Ti I emission originated from different energy states is probed. The correlation between the temporal behavior and the spatial temperature evolution are investigated under LTE condition for the possibility to use the temporal profile of Ti I emission as an indicator for LTE validity in the plasma.

  9. Recovery of phosphorus compounds from thermally-processed wastes

    Science.gov (United States)

    Czechowska-Kosacka, A.; Pawłowski, L.; Niedbala, G.; Cel, W.

    2018-05-01

    Depletion of phosphorus deposits is one of the most serious global problems, which may soon lead to a crisis in food production. It is estimated that if the current living standard is maintained, the available reserves will be depleted in 130 years. Considering the principle of sustainable development, searching for alternative phosphorus sources is extremely important. The work presented the results of the research on the possibility of utilizing wastes as a source of phosphorus. The studies were conducted on poultry manure. The physicochemical properties of phosporus-rich wastes were determined as well. The fertilizing properties of ashes from poultry manure combustion – obtained from different systems, i.e. caged and barn production. The assimilability of phosphorus from the obtained ashes was determined. Potential applications of phosphorus-rich ashes were proposed as well.

  10. Positron probing of phosphorus-vacancy complexes in silicon irradiated with 15 MeV protons

    Science.gov (United States)

    Arutyunov, N.; Emtsev, V.; Krause-Rehberg, R.; Elsayed, M.; Kessler, C.; Kozlovski, V.; Oganesyan, G.

    2015-06-01

    Defects in phosphorus-doped silicon samples of floating-zone material, n-FZ-Si(P), produced under irradiation with 15 MeV protons at room temperature are studied by positron annihilation lifetime spectroscopy over the temperature range of ∼ 30 K - 300 K and by low- temperature Hall effect measurements. After annealing of E-centersand divacancies, we detected for the first time high concentrations of positron traps which had not been observed earlier. These defects are isochronally annealed over the temperature interval of ∼ 320 °C - 700 °C they manifest themselves as electrically neutral deep donor centersin the material of n-type. A long-lived component of the positron lifetime, τ2(I2 enthalpy and entropy of annealing of these centersare Ea ∼ 1.05(0.21) eV and ΔSm ≈ 3.1(0.6)kB, respectively. It is argued that the microstructure of the defect consists of two vacancies, VV, and one atom of phosphorus, P. The split configuration of the VPV complex is shortly discussed.

  11. Fluorescence excitation-emission matrix (EEM) spectroscopy and cavity ring-down (CRD) absorption spectroscopy of oil-contaminated jet fuel using fiber-optic probes.

    Science.gov (United States)

    Omrani, Hengameh; Barnes, Jack A; Dudelzak, Alexander E; Loock, Hans-Peter; Waechter, Helen

    2012-06-21

    Excitation emission matrix (EEM) and cavity ring-down (CRD) spectral signatures have been used to detect and quantitatively assess contamination of jet fuels with aero-turbine lubricating oil. The EEM spectrometer has been fiber-coupled to permit in situ measurements of jet turbine oil contamination of jet fuel. Parallel Factor (PARAFAC) analysis as well as Principal Component Analysis and Regression (PCA/PCR) were used to quantify oil contamination in a range from the limit of detection (10 ppm) to 1000 ppm. Fiber-loop cavity ring-down spectroscopy using a pulsed 355 nm laser was used to quantify the oil contamination in the range of 400 ppm to 100,000 ppm. Both methods in combination therefore permit the detection of oil contamination with a linear dynamic range of about 10,000.

  12. Phosphorus in antique iron music wire.

    Science.gov (United States)

    Goodway, M

    1987-05-22

    Harpsichords and other wire-strung musical instruments were made with longer strings about the beginning of the 17th century. This change required stronger music wire. Although these changes coincided with the introduction of the first mass-produced steel (iron alloyed with carbon), carbon was not found in samples of antique iron harpsichord wire. The wire contained an amount of phosphorus sufficient to have impeded its conversion to steel, and may have been drawn from iron rejected for this purpose. The method used to select pig iron for wire drawing ensured the highest possible phosphorus content at a time when its presence in iron was unsuspected. Phosphorus as an alloying element has had the reputation for making steel brittle when worked cold. Nevertheless, in replicating the antique wire, it was found that lowcarbon iron that contained 0.16 percent phosphorus was easily drawn to appropriate gauges and strengths for restringing antique harpsichords.

  13. Interaction between viologen-phosphorus dendrimers and α-synuclein

    International Nuclear Information System (INIS)

    Milowska, Katarzyna; Grochowina, Justyna; Katir, Nadia; El Kadib, Abdelkrim; Majoral, Jean-Pierre; Bryszewska, Maria; Gabryelak, Teresa

    2013-01-01

    In this study the interaction between viologen-phosphorus dendrimers and α-synuclein (ASN) was examined. Polycationic viologen-phosphorus dendrimers (two positive charges per viologen unit) are novel compounds with relatively unknown properties. The influence of these viologen dendrimers on ASN was tested using fluorimetric and circular dichroism methods. ASN contains four tyrosine residues; therefore, the influence of dendrimers on protein molecular conformation by measuring the changes in the ASN fluorescence in the presence of dendrimers was evaluated. The interaction of dendrimers with free L-tyrosine was also monitored. Results show that viologen-phosphorus dendrimers interact with ASN; they quenched the fluorescence of ASN as well as free tyrosine by dynamic and static ways. However, the quenching was not accompanied by modifications in the ASN secondary structure. - Highlights: ► Interaction between viologen-phosphorus dendrimers and α-synuclein (ASN) was investigated. ► Viologen-phosphorus dendrimers can quench the fluorescence of tyrosine in ASN. ► Dendrimers caused red-shift in maximum of fluorescence. ► Viologen-phosphorus dendrimers did not change the secondary structure of ASN.

  14. Ocean acidification: One potential driver of phosphorus eutrophication.

    Science.gov (United States)

    Ge, Changzi; Chai, Yanchao; Wang, Haiqing; Kan, Manman

    2017-02-15

    Harmful algal blooms which may be limited by phosphorus outbreak increases currently and ocean acidification worsens presently, which implies that ocean acidification might lead to phosphorus eutrophication. To verify the hypothesis, oxic sediments were exposed to seawater with different pH 30days. If pH was 8.1 and 7.7, the total phosphorus (TP) content in sediments was 1.52±0.50 and 1.29±0.40mg/g. The inorganic phosphorus (IP) content in sediments exposed to seawater with pH8.1 and 7.7 was 1.39±0.10 and 1.06±0.20mg/g, respectively. The exchangeable phosphorus (Ex-P) content in sediments was 4.40±0.45 and 2.82±0.15μg/g, if seawater pH was 8.1 and 7.7. Ex-P and IP contents in oxic sediments were reduced by ocean acidification significantly (pocean acidification was one potential facilitator of phosphorus eutrophication in oxic conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Recycling phosphorus by fast pyrolysis of pig manure: concentration and extraction of phosphorus combined with formation of value-added pyrolysis products

    NARCIS (Netherlands)

    Azuara, M.; Kersten, Sascha R.A.; Kootstra, A.M.J.

    2013-01-01

    In order to recycle phosphorus from the livestock chain back to the land, fast pyrolysis of concentrated pig manure at different temperatures (400 °C, 500 °C, 600 °C), was undertaken to concentrate the phosphorus in the char fraction for recovery. Results show that 92%–97% of the phosphorus present

  16. What aspect of dietary modification in broilers controls litter water-soluble phosphorus: dietary phosphorus, phytase, or calcium?

    Science.gov (United States)

    Leytem, A B; Plumstead, P W; Maguire, R O; Kwanyuen, P; Brake, J

    2007-01-01

    Environmental concerns about phosphorus (P) losses from animal agriculture have led to interest in dietary strategies to reduce the concentration and solubility of P in manures and litters. To address the effects of dietary available phosphorus (AvP), calcium (Ca), and phytase on P excretion in broilers, 18 dietary treatments were applied in a randomized complete block design to each of four replicate pens of 28 broilers from 18 to 42 d of age. Treatments consisted of three levels of AvP (3.5, 3.0, and 2.5 g kg(-1)) combined with three levels of Ca (8.0, 6.9, and 5.7 g kg(-1)) and two levels of phytase (0 and 600 phytase units [FTU]). Phytase was added at the expense of 1.0 g kg(-1) P from dicalcium phosphate. Fresh litter was collected from pens when the broilers were 41 d of age and analyzed for total P, soluble P, and phytate P as well as P composition by (31)P nuclear magnetic resonance (NMR) spectroscopy. Results indicated that the inclusion of phytase at the expense of inorganic P or reductions in AvP decreased litter total P by 28 to 43%. Litter water-soluble P (WSP) decreased by up to 73% with an increasing dietary Ca/AvP ratio, irrespective of phytase addition. The ratio of WSP/total P in litter decreased as the dietary Ca/AvP ratio increased and was greater in the phytase-amended diets. This study indicated that while feeding reduced AvP diets with phytase decreased litter total P, the ratio of Ca/AvP in the diet was primarily responsible for effects on WSP. This is important from an environmental perspective as the amount of WSP in litter could be related to potential for off-site P losses following land application of litter.

  17. Simulating Valence-to-Core X-ray Emission Spectroscopy of Transition Metal Complexes with Time-Dependent Density Functional Theory.

    Science.gov (United States)

    Zhang, Yu; Mukamel, Shaul; Khalil, Munira; Govind, Niranjan

    2015-12-08

    Valence-to-core (VtC) X-ray emission spectroscopy (XES) has emerged as a powerful technique for the structural characterization of complex organometallic compounds in realistic environments. Since the spectrum represents electronic transitions from the ligand molecular orbitals to the core holes of the metal centers, the approach is more chemically sensitive to the metal-ligand bonding character compared with conventional X-ray absorption techniques. In this paper we study how linear-response time-dependent density functional theory (LR-TDDFT) can be harnessed to simulate K-edge VtC X-ray emission spectra reliably. LR-TDDFT allows one to go beyond the single-particle picture that has been extensively used to simulate VtC-XES. We consider seven low- and high-spin model complexes involving chromium, manganese, and iron transition metal centers. Our results are in good agreement with experiment.

  18. The effects of phosphorus limitation on carbon metabolism in diatoms.

    Science.gov (United States)

    Brembu, Tore; Mühlroth, Alice; Alipanah, Leila; Bones, Atle M

    2017-09-05

    Phosphorus is an essential element for life, serving as an integral component of nucleic acids, lipids and a diverse range of other metabolites. Concentrations of bioavailable phosphorus are low in many aquatic environments. Microalgae, including diatoms, apply physiological and molecular strategies such as phosphorus scavenging or recycling as well as adjusting cell growth in order to adapt to limiting phosphorus concentrations. Such strategies also involve adjustments of the carbon metabolism. Here, we review the effect of phosphorus limitation on carbon metabolism in diatoms. Two transcriptome studies are analysed in detail, supplemented by other transcriptome, proteome and metabolite data, to gain an overview of different pathways and their responses. Phosphorus, nitrogen and silicon limitation responses are compared, and similarities and differences discussed. We use the current knowledge to propose a suggestive model for the carbon flow in phosphorus-replete and phosphorus-limited diatom cells.This article is part of the themed issue 'The peculiar carbon metabolism in diatoms'. © 2017 The Authors.

  19. Soft X-ray emission spectroscopy used for the characterization of a-C and CN{sub x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Nepijko, S.A., E-mail: nepijko@uni-mainz.de [Institute of Physics, University of Mainz, Staudingerweg 7, 55128 Mainz (Germany); Chernenkaya, A. [Institute of Physics, University of Mainz, Staudingerweg 7, 55128 Mainz (Germany); Graduate School Materials Science in Mainz, Staudingerweg 9, 55128 Mainz (Germany); Medjanik, K.; Chernov, S.V. [Institute of Physics, University of Mainz, Staudingerweg 7, 55128 Mainz (Germany); Klimenkov, M. [Institute for Applied Materials, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Vlasenko, O.V. [Sumy State University, Rimsky-Korsakov str. 2, 40007 Sumy (Ukraine); Petrovskaya, S.S. [Frantsevich Institute for Problems of Materials Science, National Academy of Sciences of Ukraine, Krzhizhanovsky str. 3, 03142 Kiev (Ukraine); Odnodvorets, L.V. [Sumy State University, Rimsky-Korsakov str. 2, 40007 Sumy (Ukraine); Zaulichnyy, Ya.V. [National Technical University of Ukraine (KPI), Pobedy Av. 37, 03056 Kiev (Ukraine); Schönhense, G. [Institute of Physics, University of Mainz, Staudingerweg 7, 55128 Mainz (Germany)

    2015-02-27

    We present the results of a soft X-ray emission spectroscopy study of a-C and CN{sub x} films on a Si(100) substrate. Also for the characterization of the homogeneity in depth of these films electron energy loss spectroscopy measurements with localization better than 4 nm were carried out. In case of CN{sub x} films the highest diamond-like modification occurs in the region close to the Si(100) substrate. The film density decreases with increasing distance from the substrate and becomes almost constant in range of thicknesses more than ~ 2 nm. - Highlights: • CN{sub x} and a-C film densities decrease with the increase of thickness. • Density increases with the decrease of Si(100) substrate temperature at preparation. • Highest concentration of the diamond-like structure is in the substrate vicinity. • It reduces further from the substrate and stabilizes at thickness ≥ 2 nm.

  20. Phosphorus and nitrogen in the eutrophication of waters

    International Nuclear Information System (INIS)

    Salonen, S.; Frisk, T.; Kaermeniemi, T.; Niemi, J.; Pitkaenen, H.; Silvo, K.; Vuoristo, H.

    1992-01-01

    This report is a summary of the contribution of nitrogen and phosphorus in the eutrophication process of inland and coastal waters. Special attention was paid to the mechanisms of these nutrients in regulating biological processes and to the methods available in estimating their effects in the eutrophication of water bodies. The report includes five chapters which are entitled: Introduction, which is a general background to the subject with special attention to the requirements of the Finnish Water Act. Phosphorus and nitrogen as factors regulating biological processes. The topics included are: definition of eutrophication, forms of phosphorus and nitrogen and their sources to inland and coastal waters, effects of these nutrients as growth factors of phytoplankton and macrophytes and consequences of eutrophication. Estimation of the effects of phosphorus and nitrogen. The topics discussed from the point of view of the tasks of the National Board of Waters and the Environment are: estimation of the effects of phosphorus and nitrogen in the planning and supervision of industry, fish farming, peat production, municipalities, agriculture and forestry. A brief state-of-the art of the research carried out in the National Board of Waters and the Environment is given. Methods of estimating the effects of phosphorus and nitrogen loading in waters. The topics are: relationships between phosphorus and nitrogen concentrations in waters, material balances, water quality models, classification of waters and different groups of organisms as indicators of water quality. Conclusions for the estimation of the effects of phosphorus and nitrogen in receiving waters

  1. BATMAN beam properties characterization by the beam emission spectroscopy diagnostic

    Science.gov (United States)

    Bonomo, F.; Ruf, B.; Barbisan, M.; Cristofaro, S.; Schiesko, L.; Fantz, U.; Franzen, P.; Pasqualotto, R.; Riedl, R.; Serianni, G.; Wünderlich, D.

    2015-04-01

    The ITER neutral beam heating systems are based on the production and acceleration of negative ions (H/D) up to 1 MV. The requirements for the beam properties are strict: a low core beam divergence (BATMAN (BAvarian Test MAchine for Negative ions) allows for deepening the knowledge of the determination of the beam properties. One of the diagnostics routinely used to this purpose is the Beam Emission Spectroscopy (BES): the Hα light emitted in the beam is detected and the corresponding spectra are evaluated to estimate the beam divergence and the stripping losses. The BES number of lines of sight in BATMAN has been recently increased: five horizontal lines of sight providing a vertical profile of the beam permit to characterize the negative ion beam properties in relation to the source parameters. Different methods of Hα spectra analysis are here taken into account and compared for the estimation of the beam divergence and the amount of stripping. In particular, to thoroughly study the effect of the space charge compensation on the beam divergence, an additional hydrogen injection line has been added in the tank, which allows for setting different background pressure values (one order of magnitude, from about 0.04 Pa up to the source pressure) in the beam drift region.

  2. Phosphorus solubility in an acid forest soil as influenced by form of applied phosphorus and liming

    International Nuclear Information System (INIS)

    Fransson, Ann-Mari; Bergkvist, Bo; Tyler, Germund

    1999-01-01

    Sedimentary phosphorus, superphosphate, and wood-ash, as well as either sedimentary phosphorus. superphosphate or ash combined with lime, were distributed in selected plots in an 80-yr-old Norway spruce forest [Picea abies (L.) Karst]. After 2 yrs, the sedimentary phosphorus had increased the oxalate/oxalic acid-extractable P in the O-horizon, and the superphosphate had increased the oxalate/oxalic acid-extractable P in the E-horizon. At first, the percolation water from the superphosphate treatment showed high P concentrations. It soon returned to control levels, however. The percolation water from the sedimentary phosphorus treatment gradually showed increased phosphate concentrations. The wood-ash increased neither the amount of extractable P nor the P concentration in the percolation water. The oxalate/oxalic acid-extractable P from the sedimentary P treatment was reduced by liming. The P concentration in the percolation water also tended to be reduced. This was perhaps due to formation of Ca phosphates in the vicinity of the lime particles. In addition, if the solubility rate was similar to the uptake rate, it could account for the decreased P concentration

  3. Effects of white phosphorus on mallard reproduction

    Science.gov (United States)

    Vann, S.I.; Sparling, D.W.; Ottinger, M.A.

    2000-01-01

    Extensive waterfowl mortality involving thousands of ducks, geese, and swans has occurred annually at Eagle River Flats, Alaska since at least 1982. The primary agent for this mortality has been identified as white phosphorus. Although acute and subacute lethality have been described, sublethal effects are less well known. This study reports on the effects of white phosphorus on reproductive function in the mallard (Anas platyrhynchos) in captivity. Fertility, hatching success, teratogenicity, and egg laying frequency were examined in 70 adult female mallards who received up to 7 daily doses of 0, 0.5, 1.0, and 2.0 mg/kg of white phosphorus. Measurements of fertility and hatchability were reduced by the white phosphorus. Teratogenic effects were observed in embryos from hens dosed at all treatment levels. Egg laying frequency was reduced even at the lowest treatment level; treated hens required a greater number of days to lay a clutch of 12 eggs than control hens. After two doses at 2.0 mg/kg, all females stopped laying completely for a minimum of 10 days and laying frequency was depressed for at least 45 days. Fertility of 10 adult male mallards dosed with 1.0 mg/kg of white phosphorus did not differ from 10 controls, but plasma testosterone levels were significantly (p free-ranging mallards may be impaired if they are exposed to white phosphorus at typical field levels.

  4. In vivo 31P MR spectroscopy of breast tumors: preliminary results

    International Nuclear Information System (INIS)

    Choe, Bo Young; Kim, Hak Hee; Suh, Tae Suk; Shinn, Kyung Sub; Jung, Sang Seol

    1995-01-01

    To evaluate the various phosphorus metabolism of breast tumors with use of in vivo phosphorus-31 ( 31 P) MR spectroscopy (MRS). Five patients with breast tumor (benign in two, malignant in three) and three normal healthy volunteers participated in this study. All in vivo 31 P MRS examinations were performed on 1.5T whole-body MRI/MRS system by using a Free Induction Decay (FID) pulse sequence. T1-weighted MR images were used for localization of tumors. Peak areas for each phosphorus metabolite were measured using a Marquart algorithm. Breast carcinoma had a substantially larger phosphomonoester (PME) and a smaller phosphocreatine (PCr) peak intensity than normal breast tissue. This was reflected in the relatively higher PME/PCr ratio of breast carcinomas as well as phosphodiester (PDE)/PCr, inorganic phosphate (Pi)/PCr, and adenosine triphosphate (ATP)/PCr ratios, compared with normal controls. The mean pH value of breast tumor demonstrating the alkaline nature was higher than that of normal controls. Spectral patterns between benign breast disease and normal breast tissue were quite similar, and differentiation was not established. Our preliminary study suggests that in vivo 31 P MRS is a noninvasive examination which may be useful in the early differentiation of malignant breast tumors from normal and benign conditions. However, normal control and benign conditions could not be characterized on the basis of the phosphorus metabolite ratios

  5. Black phosphorus saturable absorber for ultrashort pulse generation

    Energy Technology Data Exchange (ETDEWEB)

    Sotor, J., E-mail: jaroslaw.sotor@pwr.edu.pl; Sobon, G.; Abramski, K. M. [Laser and Fiber Electronics Group, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, Wroclaw 50-370 (Poland); Macherzynski, W.; Paletko, P. [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, Wroclaw 50-372 (Poland)

    2015-08-03

    Low-dimensional materials, due to their unique and versatile properties, are very interesting for numerous applications in electronics and optoelectronics. Recently rediscovered black phosphorus, with a graphite-like layered structure, can be effectively exfoliated up to the single atomic layer called phosphorene. Contrary to graphene, it possesses a direct band gap controllable by the number of stacked atomic layers. For those reasons, black phosphorus is now intensively investigated and can complement or replace graphene in various photonics and electronics applications. Here, we demonstrate that black phosphorus can serve as a broadband saturable absorber and can be used for ultrashort optical pulse generation. The mechanically exfoliated ∼300 nm thick layers of black phosphorus were transferred onto the fiber core, and under pulsed excitation at 1560 nm wavelength, its transmission increases by 4.6%. We have demonstrated that the saturable absorption of black phosphorus is polarization sensitive. The fabricated device was used to mode-lock an Er-doped fiber laser. The generated optical solitons with the 10.2 nm bandwidth and 272 fs duration were centered at 1550 nm. The obtained results unambiguously show that black phosphorus can be effectively used for ultrashort pulse generation with performances similar or even better than currently used graphene or carbon nanotubes. This application of black phosphorus proves its great potential to future practical use in photonics.

  6. Modeling of neutron emission spectroscopy in JET discharges with fast tritons from (T)D ion cyclotron heating

    International Nuclear Information System (INIS)

    Tardocchi, M.; Gorini, G.; Andersson Sunden, E.; Conroy, S.; Ericsson, G.; Gatu Johnson, M.; Giacomelli, L.; Hellesen, C.; Hjalmarsson, A.; Kaellne, J.; Ronchi, E.; Sjoestrand, H.; Weiszflog, M.; Johnson, T.; Lamalle, P. U.

    2006-01-01

    The measurement of fast ion populations is one of the diagnostic capabilities provided by neutron emission spectroscopy (NES). NES measurements were carried out during JET trace tritium campaign with the magnetic proton recoil neutron spectrometer. A favorable plasma scenario is (T)D where the resulting 14 MeV neutron yield is dominated by suprathermal emission from energetic tritons accelerated by radio frequency at their fundamental cyclotron frequency. Information on the triton distribution function has been derived from NES data with a simple model based on two components referred to as bulk (B) and high energy (HE). The HE component is based on strongly anisotropic tritium distribution that can be used for routine best-fit analysis to provide tail temperature values (T HE ). This article addresses to what extent the T HE values are model dependent by comparing the model above with a two-temperature (bi-) Maxwellian model featuring parallel and perpendicular temperatures. The bi-Maxwellian model is strongly anisotropic and frequently used for radio frequency theory

  7. Human Cardiac 31P-MR Spectroscopy at 3 Tesla Cannot Detect Failing Myocardial Energy Homeostasis during Exercise

    NARCIS (Netherlands)

    Bakermans, Adrianus J.; Bazil, Jason N.; Nederveen, Aart J.; Strijkers, Gustav J.; Boekholdt, S. Matthijs; Beard, Daniel A.; Jeneson, Jeroen A. L.

    2017-01-01

    Phosphorus-31 magnetic resonance spectroscopy (31P-MRS) is a unique non-invasive imaging modality for probing in vivo high-energy phosphate metabolism in the human heart. We investigated whether current 31P-MRS methodology would allow for clinical applications to detect exercise-induced changes in

  8. Human Cardiac 31P-MR Spectroscopy at 3 Tesla Cannot Detect Failing Myocardial Energy Homeostasis during Exercise

    NARCIS (Netherlands)

    Bakermans, Adrianus J.; Bazil, Jason N.; Nederveen, Aart J.; Strijkers, Gustav J.; Boekholdt, S. Matthijs; Beard, Daniel A.; Jeneson, Jeroen A. L.

    2017-01-01

    Phosphorus-31 magnetic resonance spectroscopy (P-31-MRS) is a unique non-invasive imaging modality for probing in vivo high-energy phosphate metabolism in the human heart. We investigated whether current P-31-MRS methodology would allow for clinical applications to detect exercise-induced changes in

  9. High resolution X-ray emission spectroscopy: An advanced tool for actinide research

    Science.gov (United States)

    Vitova, T.; Brendebach, B.; Dardenne, K.; Denecke, M. A.; Lebid, A.; Löble, M.; Rothe, J.; Batuk, O. N.; Hormes, J.; Liu, D.; Breher, F.; Geckeis, H.

    2010-03-01

    High resolution X-ray emission spectroscopy (HRXES) is becoming increasingly important for our understanding of electronic and coordination structures. The combination of such information with development of quantum theoretical tools will advance our capability for predicting reactivity and physical behavior especially of 5f elements. HRXES can be used to remove lifetime broadening by registering the partial fluorescence yield emitted by the sample (i.e., recording a windowed signal from the energy dispersed fluorescence emission while varying incident photon energy), thereby yielding highly resolved X-ray absorption fine structure (XAFS) spectra. Such spectra often display resonant features not observed in conventional XAFS. The spectrometer set-up can also be used for a wide range of other experiments, for example, resonant inelastic X-ray scattering (RIXS), where bulk electron configuration information in solids, liquids and gases is obtained. Valence-selective XAFS studies, where the local structure of a selected element's valence state present in a mixture of valence states can be obtained, as well as site-selective XAFS studies, where the coordination structure of a metal bound to selected elements can be differentiated from that of all the other ligating atoms. A HRXES spectrometer has been constructed and is presently being commissioned for use at the INE-Beamline for actinide research at the synchrotron source ANKA at FZK. We present the spectrometer's compact, modular design, optimized for attaining a wide range of energies, and first test measurement results. Examples from HRXES studies of lanthanides, actinides counter parts, are also shown.

  10. In-situ virtual metrology for the silicon-dioxide etch rate by using optical emission spectroscopy data

    International Nuclear Information System (INIS)

    Kim, Boomsoo; Hong, Sangjeen

    2014-01-01

    As a useful tool for process control in a high volume semiconductor manufacturing environment, virtual metrology for the etch rate in a plasma etch process is investigated using optical emission spectroscopy (OES) data. Virtual metrology is a surrogate measurement taken from the process instead of from direct measurement, and it can provide in-situ metrology of a wafer's geometry from a predictive model. A statistical regression model that correlates the selected wavelengths of the optical emission spectra to the etch rate is established using the OES data collected over 20 experimental runs. In addition, an argon actinometry study is employed to quantify the OES data, and it provides valuable insight into the analysis of the OES data. The established virtual metrology model is further verified with an additional 20 runs of data. As a result, the virtual metrology model with both process recipe tool data and in-situ data shows higher prediction accuracy by as much as 56% compared with either the process recipe tool data or the in-situ data alone.

  11. Secondary electron emission studied by secondary electron energy loss coincidence spectroscopy (SE2ELCS)

    International Nuclear Information System (INIS)

    Khalid, R.

    2013-01-01

    Emission of secondary electrons is of importance in many branches of fundamental and applied science. It is widely applied in the electron microscope for the investigation of the structure and electronic state of solid surfaces and particle detection in electron multiplier devices, and generally it is related to the energy dissipation of energetic particles moving inside a solid. The process of secondary electron emission is a complex physical phenomenon, difficult to measure experimentally and treat theoretically with satisfactory accuracy. The secondary electron spectrum measured with single electron spectroscopy does not provide detailed information of the energy loss processes responsible for the emission of secondary electrons. This information can be accessed when two correlated electron pairs are measured in coincidence and the pair consists of a backscattered electron after a given energy loss and a resulting emitted secondary electron. To investigate the mechanisms responsible for the emission of secondary electrons, a reflection (e,2e) coincidence spectrometer named Secondary Electron Electron Energy Loss Coincidence Spectrometer (SE2ELCS) has been developed in the framework of this thesis which allows one to uncover the relation between the features in the spectra which are due to energy losses and true secondary electron emission structures. The correlated electron pairs are measured with a hemispherical mirror analyzer (HMA) and a time of flight analyzer (TOF) by employing a continuous electron beam. An effort has been made to increase the coincidence count rate by increasing the effective solid angle of the TOF analyzer and optimizing the experimental parameters to get optimum energy resolution. Double differential coincidence spectra for a number of materials namely, nearly free electron metals (Al, Si), noble metals (Ag, Au, Cu, W) and highly oriented pyrolytic graphite (HOPG) have been measured using this coincidence spectrometer. The

  12. Interaction between viologen-phosphorus dendrimers and {alpha}-synuclein

    Energy Technology Data Exchange (ETDEWEB)

    Milowska, Katarzyna, E-mail: milowska@biol.uni.lodz.pl [Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz (Poland); Grochowina, Justyna [Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz (Poland); Katir, Nadia [Laboratoire de Chimie de Coordination CNRS, 205 route de Narbonne, 31077 Toulouse (France); El Kadib, Abdelkrim [Institute of Nanomaterials and Nanotechnology (INANOTECH)-MAScIR (Moroccan Foundation for Advanced Science, Innovation and Research), ENSET, Avenue de I' Armee Royale, Madinat El Irfane, 10100 Rabat (Morocco); Majoral, Jean-Pierre [Laboratoire de Chimie de Coordination CNRS, 205 route de Narbonne, 31077 Toulouse (France); Bryszewska, Maria; Gabryelak, Teresa [Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz (Poland)

    2013-02-15

    In this study the interaction between viologen-phosphorus dendrimers and {alpha}-synuclein (ASN) was examined. Polycationic viologen-phosphorus dendrimers (two positive charges per viologen unit) are novel compounds with relatively unknown properties. The influence of these viologen dendrimers on ASN was tested using fluorimetric and circular dichroism methods. ASN contains four tyrosine residues; therefore, the influence of dendrimers on protein molecular conformation by measuring the changes in the ASN fluorescence in the presence of dendrimers was evaluated. The interaction of dendrimers with free L-tyrosine was also monitored. Results show that viologen-phosphorus dendrimers interact with ASN; they quenched the fluorescence of ASN as well as free tyrosine by dynamic and static ways. However, the quenching was not accompanied by modifications in the ASN secondary structure. - Highlights: Black-Right-Pointing-Pointer Interaction between viologen-phosphorus dendrimers and {alpha}-synuclein (ASN) was investigated. Black-Right-Pointing-Pointer Viologen-phosphorus dendrimers can quench the fluorescence of tyrosine in ASN. Black-Right-Pointing-Pointer Dendrimers caused red-shift in maximum of fluorescence. Black-Right-Pointing-Pointer Viologen-phosphorus dendrimers did not change the secondary structure of ASN.

  13. Radiochemical analysis of phosphorus in milk samples

    International Nuclear Information System (INIS)

    Oliveira, R.M. de; Cunha, I.I.L.

    1991-01-01

    The determination of phosphorus in milk samples by thermal neutron activation analysis employing radiochemical separation is described. The radiochemical separation consists of the simultaneous irradiation of samples and standards, dissolution of the milk samples in a perchloric acid and nitric acid mixture, addition of zinc hold-back carrier, precipitation of phosphorus as ammonium phospho molybdate (A.M.P.) and sample counting in a Geiger-Mueller detector. The analysis sources of error were studied and the established method was applied to phosphorus analyses in commercial milk samples. (author)

  14. CLINICAL APPLICABILITY OF HUMAN IN-VIVO LOCALIZED P-31 MAGNETIC-RESONANCE SPECTROSCOPY OF BONE AND SOFT-TISSUE TUMORS

    NARCIS (Netherlands)

    HOEKSTRA, HJ; BOEVE, WJ; KAMMAN, RL; MOOYAART, EL

    1994-01-01

    Background: Magnetic resonance imaging (MRI) is of restricted value for the in vivo characterization of tumor types. The applicability of phosphorus-31 (P-31) magnetic resonance spectroscopy (MRS) in the diagnosis of bone and soft tissue tumors is unknown. Methods: A total of 191 consecutive

  15. A new model of anomalous phosphorus diffusion in silicon

    International Nuclear Information System (INIS)

    Budil, M.; Poetzl, H.; Stingeder, G.; Grasserbauer, M.

    1989-01-01

    A model is presented to describe the 'kink and tail' diffusion of phosphorus. The diffusion behaviour of phosphorus is expplained by the motion of phosphorus-interstitial and phosphorus-vacancy pairs in different charge states. The model yields the enhancement of diffusion in the tail region depending on surface concentration. Furthermore it yields the same selfdiffusion coefficient for interstitials as the gold diffusion experiments. A transformation of the diffusion equation was found to reduce the number of simulation equations. (author) 7 refs., 5 figs

  16. Greenhouse gas emissions from a Danish riparian wetland before and after restoration

    DEFF Research Database (Denmark)

    Audet, Joachim; Elsgaard, Lars; Kjærgaard, Charlotte

    2013-01-01

    Restoration of riparian wetlands often aims at increasing the removal of nitrogen and phosphorus by re-establishing the hydrological connectivity between the stream and the surrounding floodplain. However, the geochemically reduced soil conditions in the newly restored area may favor the emission...

  17. Digestible phosphorus levels for barrows from 50 to 80 kg

    Directory of Open Access Journals (Sweden)

    Viviane Maria Oliveira dos Santos Nieto

    2016-05-01

    Full Text Available ABSTRACT This study was carried out to evaluate the levels of digestible phosphorus in diets for barrows with a high potential for lean meat deposition from 50 to 80 kg. Eighty barrows, with an initial weight of 47.93±3.43 kg, were distributed in completely randomized blocks, with each group given five levels of digestible phosphorus (1.86, 2.23, 2.61, 2.99, and 3.36 g kg−1. There were eight replicates, and two animals per experimental unit. Phosphorus levels did not significantly influence feed intake, weight gain, or feed conversion ratio. Daily digestible phosphorus intake increased linearly as levels of phosphorus in the diet were increased. Phosphorus levels did not significantly influence muscle depth, loin eye area, backfat thickness, or the percentage and quantity of lean meat in the carcass. A linear increase was observed for feeding cost as the levels of digestible phosphorus in the diet were increased, and the level of 1.86 g kg−1 cost 29.4% less when compared with the level of 2.61 g kg−1. The dry matter, natural matter, the coefficient of the residue, and volatile solids of the waste were not significantly influenced by phosphorus levels. Conversely, it was possible to observe an increasing linear effect for total solids, total phosphorus, and total nitrogen in the waste of animals receiving diets with increased levels of digestible phosphorus. The level of 1.86 g kg−1, which corresponded to a daily intake of 4.77 g−1 of digestible phosphorus, meets the requirements of barrows weighing 50 to 80 kg.

  18. Chromatography of phosphorus oxoacids

    International Nuclear Information System (INIS)

    Ohashi, S.

    1975-01-01

    The present state of studies on the chromatographic separation of phosphorus oxoacids is surveyed. In this paper, chromatographic techniques are divided into four groups, i.e. paper and thin-layer chromatography, paper electrophoresis, ion-exchange chromatography, and gel chromatography. The separation mechanisms and characteristics for these chromatographic methods are discussed and some examples for the separation of phosphorus oxoacids are described. As examples of the application of ion-exchange and gel chromatography, studies on the hot atom chemistry of 32 P in solid inorganic phosphates and those on the substitution reactions between diphosphonate (diphosphite) and polyphosphates are reported. (author)

  19. Effect of phosphorus level on nitrogen accumulation and yield in soybean

    International Nuclear Information System (INIS)

    You Yubo; Wu Dongmei; Gong Zhenping; Ma Chunmei

    2012-01-01

    In this paper, the 15 N labeling with sand culture was conducted to study effects of phosphorus level on nitrogen accumulation, nodule nitrogen fixation and yield of soybean plants. Results showed that nitrogen accumulation, fixation and yield of soybean plants all presented a single peak curve with improvement of phosphorus nutrition level, with the peak value of phosphorus concentration in nutrient solution of 31 mg/L. When phosphorus concentration of nutrient solution was 11 mg/L, no obvious promotion was found on the ratio of nodule nitrogen fixation when increasing phosphorus concentration again, However, when phosphorus concentration of nutrient solution was 21 mg/L, increasing phosphorus concentration again had no obvious promotion on soybean plant nitrogen accumulation, nodule nitrogen fixation accumulation and yield, indicating that effect of phosphorus nutrition level on nitrogen fixation was lower than that on yield formation level. (authors)

  20. A separation method to overcome the interference of aluminium on zinc determination by inductively coupled plasma atomic emission spectroscopy

    OpenAIRE

    Jesus, Djane S. de; Korn, Maria das Graças Andrade; Ferreira, Sergio Luis Costa; Carvalho, Marcelo Souza de

    2000-01-01

    Texto completo: acesso restrito. p.389–394 The use of polyurethane foam (PUF) to separate zinc from large amounts of aluminium and its determination by inductively coupled plasma atomic emission spectroscopy technique (ICP-AES) in aluminium matrices is described. The proposed method is based on the solid-phase extraction of the zinc(II) cation as a thiocyanate complex. Parameters such as effect of pH on zinc sorption, zinc desorption from the foam and analytical features of the procedure w...

  1. Radiation induced phosphorus segregation in austenitic and ferritic alloys

    International Nuclear Information System (INIS)

    Brimhall, J.L.; Baer, D.R.; Jones, R.H.

    1984-01-01

    The radiation induced surface segregation (RIS) of phosphorus in stainless steel attained a maximum at a dose of 0.8 dpa then decreased continually with dose. This decrease in the surface segregation of phosphorus at high dose levels has been attributed to removal of the phosphorus layer by ion sputtering. Phosphorus is not replenished since essentially all of the phosphorus within the irradiation zone has been segregated to the surface. Sputter removal can explain the previously reported absence of phosphorus segregation in ferritic alloys irradiated at high dosessup(1,2) (>1 dpa) since irradiation of ferritic alloys to low doses has shown measurable RIS. This sputtering phenomenon places an inherent limitation to the heavy ion irradiation technique for the study of surface segregation of impurity elements. The magnitude of the segregation in ferritics is still much less than in stainless steel which can be related to the low damage accumulation in these alloys. (orig.)

  2. The roles of loosely-bound and tightly-bound extracellular polymer substances in enhanced biological phosphorus removal.

    Science.gov (United States)

    Long, Xiangyu; Tang, Ran; Fang, Zhendong; Xie, Chaoxin; Li, Yongqin; Xian, Guang

    2017-12-01

    Extracellular polymeric substances (EPS) have be founded to participate in the process of enhanced biological phosphorus removal (EBPR), but the exact role of EPS in EBPR process is unclear. In this work, the roles of loosely-bound EPS (LB-EPS), tightly-bound EPS (TB-EPS) and microbial cell in EBPR were explored, taking the activated sludge from 4 lab-scale A/O-SBR reactors with different temperatures and organic substrates as objects. It was founded that the P of EBPR activated sludge was mainly stored in TB-EPS, but the P of non-EBPR activated sludge was primarily located in microbial cell. The P release and uptake of EBPR activated sludge was attributed to the combined action of TB-EPS and microbial cell. Furthermore, TB-EPS played an more important role than microbial cell in EBPR process. With the analysis of 31 P NMR spectroscopy, both polyP and orthoP were the main phosphorus species of TB-EPS in EBPR sludge, but only orthoP was the main phosphorus species of LB-EPS and microbial cell. During the anaerobic-aerobic cycle, the roles of LB-EPS, TB-EPS and microbial cell in transfer and transformation of P in EBPR sludge were obviously different. LB-EPS transported and retained orthoP, and microbial cell directly anaerobically released or aerobically absorbed orthoP. Importantly, TB-EPS not only transported and retained orthoP, but also participated in biological phosphorus accumulation. The EBPR performance of sludge was closely related with the polyp in TB-EPS, which might be synthesized and decomposed by extracellular enzyme. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Ultrafast Laser-Based Spectroscopy and Sensing: Applications in LIBS, CARS, and THz Spectroscopy

    Science.gov (United States)

    Leahy-Hoppa, Megan R.; Miragliotta, Joseph; Osiander, Robert; Burnett, Jennifer; Dikmelik, Yamac; McEnnis, Caroline; Spicer, James B.

    2010-01-01

    Ultrafast pulsed lasers find application in a range of spectroscopy and sensing techniques including laser induced breakdown spectroscopy (LIBS), coherent Raman spectroscopy, and terahertz (THz) spectroscopy. Whether based on absorption or emission processes, the characteristics of these techniques are heavily influenced by the use of ultrafast pulses in the signal generation process. Depending on the energy of the pulses used, the essential laser interaction process can primarily involve lattice vibrations, molecular rotations, or a combination of excited states produced by laser heating. While some of these techniques are currently confined to sensing at close ranges, others can be implemented for remote spectroscopic sensing owing principally to the laser pulse duration. We present a review of ultrafast laser-based spectroscopy techniques and discuss the use of these techniques to current and potential chemical and environmental sensing applications. PMID:22399883

  4. Ultrafast Laser-Based Spectroscopy and Sensing: Applications in LIBS, CARS, and THz Spectroscopy

    Directory of Open Access Journals (Sweden)

    Megan R. Leahy-Hoppa

    2010-04-01

    Full Text Available Ultrafast pulsed lasers find application in a range of spectroscopy and sensing techniques including laser induced breakdown spectroscopy (LIBS, coherent Raman spectroscopy, and terahertz (THz spectroscopy. Whether based on absorption or emission processes, the characteristics of these techniques are heavily influenced by the use of ultrafast pulses in the signal generation process. Depending on the energy of the pulses used, the essential laser interaction process can primarily involve lattice vibrations, molecular rotations, or a combination of excited states produced by laser heating. While some of these techniques are currently confined to sensing at close ranges, others can be implemented for remote spectroscopic sensing owing principally to the laser pulse duration. We present a review of ultrafast laser-based spectroscopy techniques and discuss the use of these techniques to current and potential chemical and environmental sensing applications.

  5. The impact of molecular emission in compositional depth profiling using Glow Discharge-Optical Emission Spectroscopy

    International Nuclear Information System (INIS)

    Bengtson, Arne

    2008-01-01

    The scope of this paper is to investigate and discuss how molecular emission can affect elemental analysis in glow discharge optical emission (GD-OES), particularly in compositional depth profiling (CDP) applications. Older work on molecular emission in glow discharges is briefly reviewed, and the nature of molecular emission spectra described. Work on the influence of hydrogen in the plasma, in particular elevated background due to a continuum spectrum, is discussed. More recent work from sputtering of polymers and other materials with a large content of light elements in a Grimm type source is reviewed, where substantial emission has been observed from several light diatomic molecules (CO, CH, OH, NH, C 2 ). It is discussed how the elevated backgrounds from such molecular emission can lead to significant analytical errors in the form of 'false' depth profile signals of several atomic analytical lines. Results from a recent investigation of molecular emission spectra from mixed gases in a Grimm type glow discharge are presented. An important observation is that dissociation and subsequent recombination processes occur, leading to formation of molecular species not present in the original plasma gas. Experimental work on depth profiling of a polymer coating and a thin silicate film, using a spectrometer equipped with channels for molecular emission lines, is presented. The results confirm that molecular emission gives rise to apparent depth profiles of elements not present in the sample. The possibilities to make adequate corrections for such molecular emission in CDP of organic coatings and very thin films are discussed

  6. The impact of molecular emission in compositional depth profiling using Glow Discharge-Optical Emission Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bengtson, Arne [Corrosion and Metals Research Institute, Dr. Kristinas vaeg 48, Stockholm (Sweden)], E-mail: arne.bengtson@kimab.com

    2008-09-15

    The scope of this paper is to investigate and discuss how molecular emission can affect elemental analysis in glow discharge optical emission (GD-OES), particularly in compositional depth profiling (CDP) applications. Older work on molecular emission in glow discharges is briefly reviewed, and the nature of molecular emission spectra described. Work on the influence of hydrogen in the plasma, in particular elevated background due to a continuum spectrum, is discussed. More recent work from sputtering of polymers and other materials with a large content of light elements in a Grimm type source is reviewed, where substantial emission has been observed from several light diatomic molecules (CO, CH, OH, NH, C{sub 2}). It is discussed how the elevated backgrounds from such molecular emission can lead to significant analytical errors in the form of 'false' depth profile signals of several atomic analytical lines. Results from a recent investigation of molecular emission spectra from mixed gases in a Grimm type glow discharge are presented. An important observation is that dissociation and subsequent recombination processes occur, leading to formation of molecular species not present in the original plasma gas. Experimental work on depth profiling of a polymer coating and a thin silicate film, using a spectrometer equipped with channels for molecular emission lines, is presented. The results confirm that molecular emission gives rise to apparent depth profiles of elements not present in the sample. The possibilities to make adequate corrections for such molecular emission in CDP of organic coatings and very thin films are discussed.

  7. Time-resolved FTIR emission spectroscopy of Cu in the 1800-3800 cm(-1) region: transitions involving f and g states and oscillator strengths

    Czech Academy of Sciences Publication Activity Database

    Civiš, Svatopluk; Matulková, Irena; Cihelka, Jaroslav; Kubelík, Petr; Kawaguchi, K.; Chernov, V. E.

    2011-01-01

    Roč. 44, č. 2 (2011), 025002 ISSN 0953-4075 R&D Projects: GA AV ČR IAA400400705; GA AV ČR KAN100500652 Institutional research plan: CEZ:AV0Z40400503 Keywords : metal poor stars * atomic data * FTIR emission spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.875, year: 2011

  8. Phosphorus conditions at various depths in some mineral soils

    Directory of Open Access Journals (Sweden)

    Armi Kaila

    1963-05-01

    Full Text Available The fractionation method of CHANG and JACKSON (2 was used for the analysing of the distribution of inorganic phosphorus in the topsoil and subsoil of twelve virgin and twelve cultivated soils from various parts of the country; two virgin soils and twenty cultivated soils were studied down to the depths of 60 cm or 70 cm, one even to 2 m. In the more intensively podsolized virgin soils the surface layers, particularly the A2-horizon, are very poor in all the forms of inorganic phosphorus while the enrichment layer will contain fairly high amounts of iron and aluminium bound phosphorus. The application of fertilizers and the other cultivation managements tend to accumulate aluminium and iron bound phosphorus in the plough layer. In some soils the minimum content of calcium bound phosphorus occurs in the layer below the plough layer, but an increase with the depth seems to be typical to it in all the non-Litorina soils, while the first two fractions usually decrease with the depth. In the Litorina soils the iron bound phosphorus is dominant in all the layers studied, but the content of reductant soluble phosphorus is low in these soils, and their content of calcium bound phosphorus is higher than the content of phosphorus bound by aluminium. The predominance of calcium phosphate in the subsoil and the rather low content of reductant soluble and occluded fractions indicate that the chemical weathering in most of our soils is not yet at an advanced stage. The test values determined were in accordance with the results of the fractionation and the estimation of ammonium oxalate soluble aluminium and iron.

  9. Forms and Lability of Phosphorus in Algae and Aquatic Macrophytes Characterized by Solution 31P NMR Coupled with Enzymatic Hydrolysis

    Science.gov (United States)

    Feng, Weiying; Zhu, Yuanrong; Wu, Fengchang; He, Zhongqi; Zhang, Chen; Giesy, John P.

    2016-11-01

    Solution Phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy coupled with enzymatic hydrolysis (EH) with commercially available phosphatases was used to characterize phosphorus (P) compounds in extracts of the dominant aquatic macrophytes and algae in a eutrophic lake. Total extractable organic P (Po) concentrations ranged from 504 to 1643 mg kg-1 and 2318 to 8395 mg kg-1 for aquatic macrophytes and algae, respectively. Using 31P NMR spectroscopy, 11 Po species were detected in the mono- and diester region. Additionally, orthophosphate, pyrophosphate and phosphonates were also detected. Using EH, phytate-like P was identified as the prevalent class of enzyme-labile Po, followed by labile monoester- and diester-P. Comparison of the NMR and EH data indicated that the distribution pattern of major P forms in the samples determined by the two methods was similar (r = 0.712, p < 0.05). Additional 31P NMR spectroscopic analysis of extracts following EH showed significant decreases in the monoester and pyrophosphate regions, with a corresponding increase in the orthophosphate signal, as compared to unhydrolyzed extracts. Based on these quantity and hydrolysis data, we proposed that recycling of Po in vegetative biomass residues is an important mechanism for long-term self-regulation of available P for algal blooming in eutrophic lakes.

  10. Deep level transient spectroscopy studies of charge traps introduced into silicon by channeling ion implantation of phosphorus

    International Nuclear Information System (INIS)

    McCallum, J.C.; Lay, M.; Deenapanray, P.N.K.; Jagadish, C.

    2002-01-01

    Full text: The operating conditions of a silicon-based quantum computer are expected to place stringent requirements on the quality of the material and the processes used to make it. In the Special Research Centre for Quantum Computer Technology, ion implantation is one of the principle processing techniques under investigation for forming an ordered array of phosphorus atoms. This technique introduces defect centres in silicon which act as charge traps. Charge traps are expected to be detrimental to operation of the device. These defect centres, their dependence on ion implantation and thermal annealing conditions are being quantified using Deep Level Transient Spectroscopy (DLTS). Since the aspect ratio of the masks required for the top-down fabrication process restrict the incident ions to a range of angles in which they may undergo channeling implantation in the silicon substrate, we have examined the effect of channeling implantation on the nature and quantity of the charge traps produced. This is the first time that DLTS studies have been performed for channeling implantation of a dopant species in silicon. DLTS is well-suited to the dose regime of ∼10 11 P/cm 3 required for the quantum computer, however, a standard DLTS measurement is unable to probe the shallow depth range of ∼ 20 nm required for the P atoms (∼ 10-15 keV implantation energy). Our aim has therefore been to perform P implants in the appropriate dose regime but using higher implantation energies, ∼ 75-450 keV, where DLTS can directly identify and profile the charge traps induced by the implantation step and monitor their annealing characteristics during subsequent processing. To map the behaviour observed in this energy regime onto the low energy range required for the quantum computer we are comparing the DLTS results to damage profiles predicted by the Monte Carlo code Crystal Trim which is used in the semiconductor industry to simulate ion implantation processes in crystalline

  11. Turbulence imaging and applications using beam emission spectroscopy on DIII-D (invited)

    Science.gov (United States)

    McKee, G. R.; Fenzi, C.; Fonck, R. J.; Jakubowski, M.

    2003-03-01

    Two-dimensional measurements of density fluctuations are obtained in the radial and poloidal plane of the DIII-D tokamak with the Beam Emission Spectroscopy (BES) diagnostic system. The goals are to visualize the spatial structure and time evolution of turbulent eddies, as well as to obtain the 2D statistical properties of turbulence. The measurements are obtained with an array of localized BES spatial channels configured to image a midplane region of the plasma. 32 channels have been deployed, each with a spatial resolution of about 1 cm in the radial and poloidal directions, thus providing measurements of turbulence in the wave number range 0movies have broad application to a wide variety of fundamental turbulence studies: imaging of the highly complex, nonlinear turbulent eddy interactions, measurement of the 2D correlation function, and S(kr,kθ) wave number spectra, and direct measurement of the equilibrium and time-dependent turbulence flow field. The time-dependent, two-dimensional turbulence velocity flow-field is obtained with time-delay-estimation techniques.

  12. A Simple LIBS (Laser-Induced Breakdown Spectroscopy) Laboratory Experiment to Introduce Undergraduates to Calibration Functions and Atomic Spectroscopy

    Science.gov (United States)

    Chinni, Rosemarie C.

    2012-01-01

    This laboratory experiment introduces students to a different type of atomic spectroscopy: laser-induced breakdown spectroscopy (LIBS). LIBS uses a laser-generated spark to excite the sample; once excited, the elemental emission is spectrally resolved and detected. The students use LIBS to analyze a series of standard synthetic silicate samples…

  13. Method validation in plasma source optical emission spectroscopy (ICP-OES) - From samples to results

    International Nuclear Information System (INIS)

    Pilon, Fabien; Vielle, Karine; Birolleau, Jean-Claude; Vigneau, Olivier; Labet, Alexandre; Arnal, Nadege; Adam, Christelle; Camilleri, Virginie; Amiel, Jeanine; Granier, Guy; Faure, Joel; Arnaud, Regine; Beres, Andre; Blanchard, Jean-Marc; Boyer-Deslys, Valerie; Broudic, Veronique; Marques, Caroline; Augeray, Celine; Bellefleur, Alexandre; Bienvenu, Philippe; Delteil, Nicole; Boulet, Beatrice; Bourgarit, David; Brennetot, Rene; Fichet, Pascal; Celier, Magali; Chevillotte, Rene; Klelifa, Aline; Fuchs, Gilbert; Le Coq, Gilles; Mermet, Jean-Michel

    2017-01-01

    Even though ICP-OES (Inductively Coupled Plasma - Optical Emission Spectroscopy) is now a routine analysis technique, requirements for measuring processes impose a complete control and mastering of the operating process and of the associated quality management system. The aim of this (collective) book is to guide the analyst during all the measurement validation procedure and to help him to guarantee the mastering of its different steps: administrative and physical management of samples in the laboratory, preparation and treatment of the samples before measuring, qualification and monitoring of the apparatus, instrument setting and calibration strategy, exploitation of results in terms of accuracy, reliability, data covariance (with the practical determination of the accuracy profile). The most recent terminology is used in the book, and numerous examples and illustrations are given in order to a better understanding and to help the elaboration of method validation documents

  14. [Real time diagnostics of instantaneous temperature of combustion and explosion process by modern spectroscopy].

    Science.gov (United States)

    Zhou, Xue-tie; Wang, Jun-de; Li, Yan; Liu, Da-bing

    2003-04-01

    The combustion temperature is one of the important parameters to express flame combustion and explosion characteristics. It will effectively guide the design and manufacture of new model explosives, industrial explosive materials, and weapons. The recent developments and applications of real time diagnostics of instantaneous temperature of combustion and explosion processes by modern spectroscopic methods, such as atomic absorption-emission method, atomic emission two-line spectroscopy, atomic emission multiline spectroscopy, molecular rotation-vibration spectroscopy, coherent anti-stokes Raman scattering (CARS) and plane laser-induced fluorescence (PLIF), were reviewed in this paper. The maximum time resolution of atomic absorption-emission method is 25 microseconds. The time resolution of atomic emission two-line spectroscopy can reach 0.1 microsecond. These two methods can completely suit the need of real time and instantaneous temperature diagnostics of violent explosion and flame combustion. Other methods will also provide new effective research methods for the processes and characteristics of combustion, flame and explosion.

  15. Iron oxides, divalent cations, silica, and the early earth phosphorus crisis

    DEFF Research Database (Denmark)

    Jones, C.; Nomosatryo, S.; Crowe, S.A.

    2015-01-01

    As a nutrient required for growth, phosphorus regulates the activity of life in the oceans. Iron oxides sorb phosphorus from seawater, and through the Archean and early Proterozoic Eons, massive quantities of iron oxides precipitated from the oceans, producing a record of seawater chemistry...... that is preserved as banded iron formations (BIFs) today. Here we show that Ca2+, Mg2+, and silica in seawater control phosphorus sorption onto iron oxides, influencing the record of seawater phosphorus preserved in BIFs. Using a model for seawater cation chemistry through time, combined with the phosphorus...... waters shifted from phosphorus to iron limiting....

  16. Evaluation of added phosphorus in six volcanic ash soils

    International Nuclear Information System (INIS)

    Pino N, I.; Casas G, L.; Urbinsa P, M.C.

    1984-01-01

    The behaviour of added phosphorus in six volcanic ash soils (Andepts) was studied. Two phosphate retention solution were used; one of them labeled with 32 P carrier free. The phosphate retention solution (25 ml) was added to 5 gr of air dry soil. The remainder phosphorus in solution was measured through colorimetry and liquid scintillation. Over 85% phosphorus retention was measured in five soils. A phosphate retention solution labeled with 32 P carrier free proved to be efficient for the determination of phosphorus retention rates in the volcanic ash soils studied. (Author)

  17. Phosphorus dynamics in and below the redoxcline in the Black Sea and implications for phosphorus burial

    Science.gov (United States)

    Dijkstra, N.; Kraal, P.; Séguret, M. J. M.; Flores, M. R.; Gonzalez, S.; Rijkenberg, M. J. A.; Slomp, C. P.

    2018-02-01

    Marine basins with oxygen-depleted deep waters provide a natural laboratory to investigate the consequences of anoxic and sulfidic (i.e. euxinic) conditions for biogeochemical processes in seawater and sediments. In this study, we investigate the dynamics of the key nutrient phosphorus (P) and associated elements such as manganese (Mn), iron (Fe) and calcium (Ca) in the euxinic deep basin of the Black Sea. By examining water column particles with scanning electron microscope - energy dispersive spectroscopy and synchrotron-based X-ray absorption spectroscopy, we show that Mn(III/IV)-P is the key form of particulate P in the redoxcline. Other forms of particulate P include organic P, Fe(III)-P, and inorganic polyphosphates. Most inorganic P particles that are formed in the redoxcline subsequently dissolve in the underlying sulfidic waters, with the exception of some particulate Fe(III)-P that accounts for <1% of all P settling onto the seafloor. Organic P is the dominant source of P to the sediment. Most of this organic P is degraded in the upper 2 cm of the sediment. Results of sequential extractions and a 33P radiotracer experiment point towards the formation of labile Ca-P and P adsorbed onto calcium-carbonate and clays and a role of these phases as a major sink of P in the sediment. The total P burial efficiency in the sediments is ∼27%, which is relatively high when compared to estimates for sediments in other euxinic basins such as the Baltic Sea (<12%). We suggest that the abundant presence of calcium carbonate may contribute to the more efficient sequestration of P in Black Sea sediments.

  18. Application of X-ray spectroscopy in nondestructive photon activation analysis

    International Nuclear Information System (INIS)

    Weise, H.-P.; Segebade, Chr.

    1977-01-01

    The use of X-ray spectroscopy for the qualitative and quantitative analysis of samples activated by 30 MeV bremsstrahlung from an electron linear accelerator. Detection limits are calculated from the measured X-ray spectra and compared with those for γ-ray spectroscopy. In general, the detection limits for γ-ray and X-ray spectroscopy are comparable. Higher sensitivities for X-ray spectroscopy are observed when only low intensity γ-rays are emitted by the activation products. X-ray spectroscopy should be applied in three cases: (a) low γ-ray emission probability, (b) extremely complicated γ-ray spectrum, (c) overlapping of γ-ray lines from different elements. γ-ray spectroscopy should be preferred for the analysis of light elements for two reasons: very strong absorption of low energy X-rays (low Z) within the sample, low X-ray emission probability for the activation products of light elements. Therefore no attempt was made to use X-ray spectroscopy for the analysis of elements below Ti. Some practical applications of X-ray spectroscopy in nondestructive multielement analysis are quoted. (T.G.)

  19. Total phosphorus recovery in flowback fluids after gelled hydrocarbon fracturing fluid treatments

    Energy Technology Data Exchange (ETDEWEB)

    Fyten, G.; Houle, P.; Taylor, R.S. [Halliburton Energy Services, Calgary, AB (Canada); Stemler, P.S. [Petro-Canada Oil and Gas Inc., Calgary, AB (Canada); Lemieux, A. [Omnicon Consultants Inc., Calgary, AB (Canada)

    2006-07-01

    Carbon dioxide miscible hydrocarbon fracturing fluids are used in unconventional gas reservoirs such as tight gas, shale gas, and coalbed methane. These fracturing fluids address phase trapping concerns by using oil-based fracturing fluid technology for use in reservoirs that are water sensitive. This paper addressed the problem of refinery tower fouling caused by volatile phosphorous components found in phosphate ester oil gellants. In order to address costly unplanned refinery shutdowns, a maximum 0.5 ppm volatile phosphorus in crude specification has been proposed. However, this specification is based on average concentrations of phosphorus added to the oil to gel it. The specification also falsely assumes that the oil is phosphorus free to begin with. The authors noted that refinery tower fouling is actually the result of total phosphorus throughput rather than peak concentrations at any one point. This paper focused on the total phosphorus recovery in addition to peak concentrations. It also examined what percentage of the total recovered phosphorus is in fact volatile, since this is the material that plugs the trays. The total per cent recovery of phosphorus originally added as phosphorus based gellant was examined along with the total percent recovery of volatile phosphorus as a function of total phosphorus. The phosphorus concentrations in both new and reused fracturing fluids before addition of gellants was also examined along with the potential explanations for phosphorus concentrations higher than those originally added. It was shown that the first 50 per cent of a hydraulic fracturing fluid flowback can result in recovery of greater than or less than the amount of phosphorus added to that portion of the fracturing fluid. The initial high concentrations of total and volatile phosphorus are greater than the phosphorus concentrations inherent in the system. Therefore, as flowback continues, there would be a rapid decline in the concentration of phosphorus

  20. Isotopically exchangeable phosphorus

    International Nuclear Information System (INIS)

    Barbaro, N.O.

    1984-01-01

    A critique revision of isotope dilution is presented. The concepts and use of exchangeable phosphorus, the phosphate adsorption, the kinetics of isotopic exchange and the equilibrium time in soils are discussed. (M.A.C.) [pt

  1. Neutron activation analysis for calibration of phosphorus implantation dose

    International Nuclear Information System (INIS)

    Paul, Rick L.; Simons, David S.

    2001-01-01

    A feasibility study was undertaken to determine if radiochemical neutron activation analysis (RNAA) can be used to certify the retained dose of phosphorus implanted in silicon, with the goal of producing a phosphorus SRM. Six pieces of silicon, implanted with a nominal phosphorus dose of 8.5x10 14 atoms·cm -2 were irradiated at a neutron flux of 1.05x10 14 cm -2 ·s -1 . The samples were mixed with carrier, dissolved in acid, the phosphorus isolated by chemical separation, and 32 P measured using a beta proportional counter. A mean phosphorus concentration of (8.35±0.20)x10 14 atoms·cm -2 (uncertainty=1 standard deviation) was determined for the six samples, in agreement with the nominal implanted dose

  2. Goldtraces on wedge-shaped artefacts from late neolithic of south Scandinavia analysed by proton induced x-ray emission spectroscopy

    International Nuclear Information System (INIS)

    Ahlberg, M.; Akselsson, R.; Forkman, B.; Rausing, G.

    1975-01-01

    Visible coloured traces on the surface of two selected wedge-shaped artefacts (pendants) of slate from the late Neolithic of South Scandinavia was analysed by means of proton-induced x-ray emission spectroscopy (PIXE). PIXE is shown to be a feasible tool in investigating surface layers of archeological significance. Three different gold-silver alloys was found on the two pendants. The results indicate that we shall have to reconsider the general accepted theories on the economic basis of the early Bronze Age in the area. (author)

  3. Studies on phosphorus utilization as influenced by bacterial seed inoculation and phosphorus fertilization in summer mung (Vigna radiata L. Wilczek)

    International Nuclear Information System (INIS)

    Kothari, S.K.; Saraf, C.S.

    1988-01-01

    A greenhouse experiment was conducted with four types of bacterial inoculation (Rhizobium alone; Rhizobium along with Azotobacter chroococcum; Rhizobium along with Azospirillum brasilense and no inoculation) and three levels of phosphorus ( 32 P labelled SSP) application (O, 6.5 ppm and 13.0 ppm P). Inoculation with Rhizobium along with Azotobacter chroococcum was found to be better than Rhizobium alone or Rhizobium along with Azospirillum brasilense in respect of leaf, stem, root and nodule dry weight, phosphorus uptake and utilization efficiency. P application upto 6.5 ppm significantly increased leaf, stem, root and nodule dry weight and phosphorus uptake. Per cent phosphorus derived from fertilizer (per cent pdff) and fertilizer P uptake significantly increased while P utilization efficiency significantly decreased with increasing levels of P application. (author). 12 refs., 2 tables

  4. Effects of phosphorus doping by plasma immersion ion implantation on the structural and optical characteristics of Zn0.85Mg0.15O thin films

    International Nuclear Information System (INIS)

    Saha, S.; Nagar, S.; Chakrabarti, S.

    2014-01-01

    ZnMgO thin films deposited on 〈100〉 Si substrates by RF sputtering were annealed at 800, 900, and 1000 °C after phosphorus plasma immersion ion implantation. X-ray diffraction spectra confirmed the presence of 〈101 ¯ 0〉 and 〈101 ¯ 3〉 peaks for all the samples. However, in case of the annealed samples, the 〈0002〉 peak was also observed. Scanning electron microscopy images revealed the variation in surface morphology caused by phosphorus implantation. Implanted and non-implanted samples were compared to examine the effects of phosphorus implantation on the optical properties of ZnMgO. Optical characteristics were investigated by low-temperature (15 K) photoluminescence experiments. Inelastic exciton–exciton scattering and localized, and delocalized excitonic peaks appeared at 3.377, 3.42, and 3.45 eV, respectively, revealing the excitonic effect resulting from phosphorus implantation. This result is important because inelastic exciton–exciton scattering leads to nonlinear emission, which can improve the performance of many optoelectronic devices

  5. Improving phosphorus availability in an acid soil using organic amendments produced from agroindustrial wastes.

    Science.gov (United States)

    Ch'ng, Huck Ywih; Ahmed, Osumanu Haruna; Majid, Nik Muhamad Ab

    2014-01-01

    In acid soils, soluble inorganic phosphorus is fixed by aluminium and iron. To overcome this problem, acid soils are limed to fix aluminium and iron but this practice is not economical. The practice is also not environmentally friendly. This study was conducted to improve phosphorus availability using organic amendments (biochar and compost produced from chicken litter and pineapple leaves, resp.) to fix aluminium and iron instead of phosphorus. Amending soil with biochar or compost or a mixture of biochar and compost increased total phosphorus, available phosphorus, inorganic phosphorus fractions (soluble inorganic phosphorus, aluminium bound inorganic phosphorus, iron bound inorganic phosphorus, redundant soluble inorganic phosphorus, and calcium bound phosphorus), and organic phosphorus. This was possible because the organic amendments increased soil pH and reduced exchangeable acidity, exchangeable aluminium, and exchangeable iron. The findings suggest that the organic amendments altered soil chemical properties in a way that enhanced the availability of phosphorus in this study. The amendments effectively fixed aluminium and iron instead of phosphorus, thus rendering phosphorus available by keeping the inorganic phosphorus in a bioavailable labile phosphorus pool for a longer period compared with application of Triple Superphosphate without organic amendments.

  6. Improving Phosphorus Availability in an Acid Soil Using Organic Amendments Produced from Agroindustrial Wastes

    Directory of Open Access Journals (Sweden)

    Huck Ywih Ch’ng

    2014-01-01

    Full Text Available In acid soils, soluble inorganic phosphorus is fixed by aluminium and iron. To overcome this problem, acid soils are limed to fix aluminium and iron but this practice is not economical. The practice is also not environmentally friendly. This study was conducted to improve phosphorus availability using organic amendments (biochar and compost produced from chicken litter and pineapple leaves, resp. to fix aluminium and iron instead of phosphorus. Amending soil with biochar or compost or a mixture of biochar and compost increased total phosphorus, available phosphorus, inorganic phosphorus fractions (soluble inorganic phosphorus, aluminium bound inorganic phosphorus, iron bound inorganic phosphorus, redundant soluble inorganic phosphorus, and calcium bound phosphorus, and organic phosphorus. This was possible because the organic amendments increased soil pH and reduced exchangeable acidity, exchangeable aluminium, and exchangeable iron. The findings suggest that the organic amendments altered soil chemical properties in a way that enhanced the availability of phosphorus in this study. The amendments effectively fixed aluminium and iron instead of phosphorus, thus rendering phosphorus available by keeping the inorganic phosphorus in a bioavailable labile phosphorus pool for a longer period compared with application of Triple Superphosphate without organic amendments.

  7. Occurrence of phosphorus in groundwater and surface water of northwestern Mississippi

    Science.gov (United States)

    Welch, Heather L.; Kingsbury, James A.; Coupe, Richard H.

    2010-01-01

    Previous localized studies of groundwater samples from the Mississippi River Valley alluvial (MRVA) aquifer have demonstrated that dissolved phosphorus concentrations in the aquifer are much higher than the national background concentration of 0.03 milligram per liter (mg/L) found in 400 shallow wells across the country. Forty-six wells screened in the MRVA aquifer in northwestern Mississippi were sampled from June to October 2010 to characterize the occurrence of phosphorus in the aquifer, as well as the factors that might contribute to high dissolved phosphorus concentrations in groundwater. Dissolved phosphorus concentrations ranged from 0.12 to 1.2 mg/L with a median concentration of 0.62 mg/L. The predominant subunit of the MRVA aquifer in northwestern Mississippi is the Holocene alluvium in which median dissolved phosphorus concentrations were higher than the Pleistocene valley trains deposits subunit. Highest phosphorus concentrations occurred in water from wells located along the Mississippi River. A general association between elevated phosphorus concentrations and dissolved iron concentrations suggests that reducing conditions that mobilize iron in the MRVA aquifer also might facilitate transport of phosphorus. Using baseflow separation to estimate the contribution of baseflow to total streamflow, the estimated contribution to the total phosphorus load associated with baseflow at the Tensas River at Tendal, LA, and at the Bogue Phalia near Leland, MS, was 23 percent and 8 percent, respectively. This analysis indicates that elevated concentrations of dissolved phosphorus in the MRVA aquifer could be a possible source of phosphorus to streams during baseflow conditions. However, the fate of phosphorus in groundwater discharge and irrigation return flow to streams is not well understood.

  8. Secondary poisoning of kestrels by white phosphorus

    Science.gov (United States)

    Sparling, D.W.; Federoff, N.E.

    1997-01-01

    Since 1982, extensive waterfowl mortality due to white phosphorus (P4) has been observed at Eagle River Flats, a tidal marsh near Anchorage, Alaska. Ducks and swans that ingest P4 pellets become lethargic and may display severe convulsions. Intoxicated waterfowl attract raptors and gulls that feed on dead or dying birds. To determine if avian predators can be affected by secondary poisoning, we fed American kestrels (Falco sparverius) 10-day-old domestic chickens that had been dosed with white phosphorus. Eight of 15 kestrels fed intact chicks with a pellet of P4 implanted in their crops died within seven days. Three of 15 kestrels fed chicks that had their upper digestive tracts removed to eliminate any pellets of white phosphorus also died. Hematocrit and hemoglobin in kestrels decreased whereas lactate dehydrogenaseL, glucose, and alanine aminotransferase levels in plasma increased with exposure to contaminated chicks. Histological examination of liver and kidneys showed that the incidence and severity of lesions increased when kestrels were fed contaminated chicks. White phosphorus residues were measurable in 87% of the kestrels dying on study and 20% of the survivors. This study shows that raptors can become intoxicated either by ingesting portions of digestive tracts containing white phosphorus pellets or by consuming tissues of P4 contaminated prey.

  9. Experimental study of radiative energy transport in dense plasmas by emission and absorption spectroscopy

    International Nuclear Information System (INIS)

    Dozieres, Maylis

    2016-01-01

    This PhD work is an experimental study, based on emission and absorption spectroscopy of hot and dense nanosecond laser-produced plasmas. Atomic physics in such plasmas is a complex subject and of great interest especially in the fields of astrophysics or inertial confinement fusion. On the atomic physics point of view, this means determining parameters such as the average ionization or opacity in plasmas at given electronic temperature and density. Atomic physics codes then need of experimental data to improve themselves and be validated so that they can be predictive for a wide range of plasmas. With this work we focus on plasmas whose electronic temperature varies from 10 eV to more than a hundred and whose density range goes from 10 -5 ato10 -2 g/cm 3 . In this thesis, there are two types of spectroscopic data presented which are both useful and necessary to the development of atomic physics codes because they are both characteristic of the state of the studied plasma: 1) some absorption spectra from Cu, Ni and Al plasmas close to local thermodynamic equilibrium; 2) some emission spectra from non local thermodynamic equilibrium plasmas of C, Al and Cu. This work highlights the different experimental techniques and various comparisons with atomic physics codes and hydrodynamics codes. (author) [fr

  10. The Spatial-temperal Distribution of Phosphorus Species and the Main Factors Influencing on Phosphorus Transportation in Middle Reaches of the Yarlung Zangbo River, China

    Science.gov (United States)

    Pu, X.; An, R.; Li, R.; Huang, W.; Li, J.

    2017-12-01

    The objectives of the current study are to investigate the spatial, temperal variation of phisphorus (P) fraction in middle reaches of the Yarlung Zangbo River of China. Samples were collected in April (dry season), August (wet season), and Octber (normal season) along with the middle reaches from Lazi site to Nuxia sitewhich which is about 1000km long. Sequential extraction were applied to determine the forms of phosphorus in suspended particles and to assess the potential bioavailability of particulate P. The results indicated that the distribution of suspended particle size inflenced not only the total phosphorus concentration, but also the proportions of different forms of phosphorus. The exchangeable phosphorus (Ex-P), Fe-bound-P, Ca-bound-P were the most aboundant forms and the highest proportions of total P. The total P concentrations were closely relative to the concentration of suspended particles. According to the characteristics of suspended particles in the Yarlung Zangbo River, the relationship between the suspended particles size and species of phosphorus was established though statistical analysis. The Ex-P increased with the decreasing of suspended particulate size. The content of bioavailable particulate phosphorus varied greatly with the proportions of particulate size. In genral, the higher the proportion of smaller particle size, the higher the content of bioavailable phosphorus. The main factors which affect the phosphorus transportation in Yarlung Zangbo River had also been discussed.

  11. Phytoextraction of excess soil phosphorus

    International Nuclear Information System (INIS)

    Sharma, Nilesh C.; Starnes, Daniel L.; Sahi, Shivendra V.

    2007-01-01

    In the search for a suitable plant to be used in P phytoremediation, several species belonging to legume, vegetable and herb crops were grown in P-enriched soils, and screened for P accumulation potentials. A large variation in P concentrations of different plant species was observed. Some vegetable species such as cucumber (Cucumis sativus) and yellow squash (Cucurbita pepo var. melopepo) were identified as potential P accumulators with >1% (dry weight) P in their shoots. These plants also displayed a satisfactory biomass accumulation while growing on a high concentration of soil P. The elevated activities of phosphomonoesterase and phytase were observed when plants were grown in P-enriched soils, this possibly contributing to high P acquisition in these species. Sunflower plants also demonstrated an increased shoot P accumulation. This study shows that the phytoextraction of phosphorus can be effective using appropriate plant species. - Crop plants such as cucumber, squash and sunflower accumulate phosphorus and thus can be used in the phytoextraction of excess phosphorus from soils

  12. Phytoextraction of excess soil phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Nilesh C. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Starnes, Daniel L. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Sahi, Shivendra V. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States)]. E-mail: shiv.sahi@wku.edu

    2007-03-15

    In the search for a suitable plant to be used in P phytoremediation, several species belonging to legume, vegetable and herb crops were grown in P-enriched soils, and screened for P accumulation potentials. A large variation in P concentrations of different plant species was observed. Some vegetable species such as cucumber (Cucumis sativus) and yellow squash (Cucurbita pepo var. melopepo) were identified as potential P accumulators with >1% (dry weight) P in their shoots. These plants also displayed a satisfactory biomass accumulation while growing on a high concentration of soil P. The elevated activities of phosphomonoesterase and phytase were observed when plants were grown in P-enriched soils, this possibly contributing to high P acquisition in these species. Sunflower plants also demonstrated an increased shoot P accumulation. This study shows that the phytoextraction of phosphorus can be effective using appropriate plant species. - Crop plants such as cucumber, squash and sunflower accumulate phosphorus and thus can be used in the phytoextraction of excess phosphorus from soils.

  13. Do invasive mussels restrict offshore phosphorus transport in Lake Huron?

    Science.gov (United States)

    Cha, Yoonkyung; Stow, Craig A; Nalepa, Thomas F; Reckhow, Kenneth H

    2011-09-01

    Dreissenid mussels were first documented in the Laurentian Great Lakes in the late 1980s. Zebra mussels (Dreissena polymorpha) spread quickly into shallow, hard-substrate areas; quagga mussels (Dreissena rostriformis bugensis) spread more slowly and are currently colonizing deep, offshore areas. These mussels occur at high densities, filter large water volumes while feeding on suspended materials, and deposit particulate waste on the lake bottom. This filtering activity has been hypothesized to sequester tributary phosphorus in nearshore regions reducing offshore primary productivity. We used a mass balance model to estimate the phosphorus sedimentation rate in Saginaw Bay, a shallow embayment of Lake Huron, before and after the mussel invasion. Our results indicate that the proportion of tributary phosphorus retained in Saginaw Bay increased from approximately 46-70% when dreissenids appeared, reducing phosphorus export to the main body of Lake Huron. The combined effects of increased phosphorus retention and decreased phosphorus loading have caused an approximate 60% decrease in phosphorus export from Saginaw Bay to Lake Huron. Our results support the hypothesis that the ongoing decline of preyfish and secondary producers including diporeia (Diporeia spp.) in Lake Huron is a bottom-up phenomenon associated with decreased phosphorus availability in the offshore to support primary production.

  14. Proton-Induced X-Ray Emission Analysis of Crematorium Emissions

    Science.gov (United States)

    Ali, Salina; Nadareski, Benjamin; Yoskowitz, Joshua; Labrake, Scott; Vineyard, Michael

    2014-09-01

    There has been considerable debate in recent years about possible mercury emissions from crematoria due to amalgam tooth restorations. We have performed a proton-induced X-ray emission (PIXE) analysis of aerosol and soil samples taken near the Vale Cemetery Crematorium in Schenectady, NY, to address this concern. The aerosol samples were collected on the roof of the crematorium using a nine-stage, cascade impactor that separates the particulate matter by aerodynamic diameter and deposits it onto thin Kapton foils. The soil samples were collected at several different distances from the crematorium and compressed into pellets with a hydraulic press. The Kapton foils containing the aerosol samples and the soil pellets were bombarded with 2.2-MeV protons from the 1.1-MV tandem Pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. We measured significant concentrations of sulfur, phosphorus, potassium, calcium, and iron, but essentially no mercury in the aerosol samples. The lower limit of detection for airborne mercury in this experiment was approximately 0.2 ng / m3. The PIXE analysis of the soil samples showed the presence of elements commonly found in soil (Si, K, Ca, Ti, Mn, Fe), but no trace of mercury. There has been considerable debate in recent years about possible mercury emissions from crematoria due to amalgam tooth restorations. We have performed a proton-induced X-ray emission (PIXE) analysis of aerosol and soil samples taken near the Vale Cemetery Crematorium in Schenectady, NY, to address this concern. The aerosol samples were collected on the roof of the crematorium using a nine-stage, cascade impactor that separates the particulate matter by aerodynamic diameter and deposits it onto thin Kapton foils. The soil samples were collected at several different distances from the crematorium and compressed into pellets with a hydraulic press. The Kapton foils containing the aerosol samples and the soil pellets were bombarded with 2.2-Me

  15. Spectroscopy of bound multi exciton complexes and deep centers in implanted and annealed silicon

    International Nuclear Information System (INIS)

    Babich, V.M.; Valakh, M.Ya.; Kovalchuk, V.B.; Rudko, G.Yu.; Shakhrajchuk, N.I.

    1989-01-01

    The change of silicon properties relevant to device physics caused by ion implantation and thermal annealing is studied. It is shown that in boron-doped p-Si the increase of P + ions implantation doses from 10 12 to 10 14 ions/cm 2 lead to a decrease of the broadening of boron bound exciton bands. This behaviour is caused by implantation-induced disordering of the lattice. The subsequent thermal annealing restores the intensity and the halfwidth of the above-mentioned bands and initiates the increase of the bands which correspond to excitons bond on the implanted phosphorus ions. Measurements of phosphorus bound exciton band intensities are applicable to the characterization of the process of phosphorus activation. Analysis of low energy region of luminescence spectra of heat treated samples shows that there is a correlation between the process of implanted phosphorus activation and the one of radiation defects transformation. The influence of germanium doping on the generation of thermal donors by means of spectroscopy of deep centres luminescence has been investigated. It is shown that the introduction of germanium in concentrations of 10 19 -10 20 cm -3 effectively suppresses the generation of thermal donors and deep centres under investigation. (author)

  16. The Prevalence of Phosphorus Containing Food Additives in Top Selling Foods in Grocery Stores

    Science.gov (United States)

    León, Janeen B.; Sullivan, Catherine M.; Sehgal, Ashwini R.

    2013-01-01

    Objective To determine the prevalence of phosphorus-containing food additives in best selling processed grocery products and to compare the phosphorus content of a subset of top selling foods with and without phosphorus additives. Design The labels of 2394 best selling branded grocery products in northeast Ohio were reviewed for phosphorus additives. The top 5 best selling products containing phosphorus additives from each food category were matched with similar products without phosphorus additives and analyzed for phosphorus content. Four days of sample meals consisting of foods with and without phosphorus additives were created and daily phosphorus and pricing differentials were computed. Setting Northeast Ohio Main outcome measures Presence of phosphorus-containing food additives, phosphorus content Results 44% of the best selling grocery items contained phosphorus additives. The additives were particularly common in prepared frozen foods (72%), dry food mixes (70%), packaged meat (65%), bread & baked goods (57%), soup (54%), and yogurt (51%) categories. Phosphorus additive containing foods averaged 67 mg phosphorus/100 gm more than matched non-additive containing foods (p=.03). Sample meals comprised mostly of phosphorus additive-containing foods had 736 mg more phosphorus per day compared to meals consisting of only additive-free foods. Phosphorus additive-free meals cost an average of $2.00 more per day. Conclusion Phosphorus additives are common in best selling processed groceries and contribute significantly to their phosphorus content. Moreover, phosphorus additive foods are less costly than phosphorus additive-free foods. As a result, persons with chronic kidney disease may purchase these popular low-cost groceries and unknowingly increase their intake of highly bioavailable phosphorus. PMID:23402914

  17. The prevalence of phosphorus-containing food additives in top-selling foods in grocery stores.

    Science.gov (United States)

    León, Janeen B; Sullivan, Catherine M; Sehgal, Ashwini R

    2013-07-01

    The objective of this study was to determine the prevalence of phosphorus-containing food additives in best-selling processed grocery products and to compare the phosphorus content of a subset of top-selling foods with and without phosphorus additives. The labels of 2394 best-selling branded grocery products in northeast Ohio were reviewed for phosphorus additives. The top 5 best-selling products containing phosphorus additives from each food category were matched with similar products without phosphorus additives and analyzed for phosphorus content. Four days of sample meals consisting of foods with and without phosphorus additives were created, and daily phosphorus and pricing differentials were computed. Presence of phosphorus-containing food additives, phosphorus content. Forty-four percent of the best-selling grocery items contained phosphorus additives. The additives were particularly common in prepared frozen foods (72%), dry food mixes (70%), packaged meat (65%), bread and baked goods (57%), soup (54%), and yogurt (51%) categories. Phosphorus additive-containing foods averaged 67 mg phosphorus/100 g more than matched nonadditive-containing foods (P = .03). Sample meals comprised mostly of phosphorus additive-containing foods had 736 mg more phosphorus per day compared with meals consisting of only additive-free foods. Phosphorus additive-free meals cost an average of $2.00 more per day. Phosphorus additives are common in best-selling processed groceries and contribute significantly to their phosphorus content. Moreover, phosphorus additive foods are less costly than phosphorus additive-free foods. As a result, persons with chronic kidney disease may purchase these popular low-cost groceries and unknowingly increase their intake of highly bioavailable phosphorus. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  18. Phosphorus Processing—Potentials for Higher Efficiency

    Directory of Open Access Journals (Sweden)

    Ludwig Hermann

    2018-05-01

    Full Text Available In the aftermath of the adoption of the Sustainable Development Goals (SDGs and the Paris Agreement (COP21 by virtually all United Nations, producing more with less is imperative. In this context, phosphorus processing, despite its high efficiency compared to other steps in the value chain, needs to be revisited by science and industry. During processing, phosphorus is lost to phosphogypsum, disposed of in stacks globally piling up to 3–4 billion tons and growing by about 200 million tons per year, or directly discharged to the sea. Eutrophication, acidification, and long-term pollution are the environmental impacts of both practices. Economic and regulatory framework conditions determine whether the industry continues wasting phosphorus, pursues efficiency improvements or stops operations altogether. While reviewing current industrial practice and potentials for increasing processing efficiency with lower impact, the article addresses potentially conflicting goals of low energy and material use as well as Life Cycle Assessment (LCA as a tool for evaluating the relative impacts of improvement strategies. Finally, options by which corporations could pro-actively and credibly demonstrate phosphorus stewardship as well as options by which policy makers could enforce improvement without impairing business locations are discussed.

  19. The role of phosphorus sources in the growth of lowland rice plant

    International Nuclear Information System (INIS)

    Sisworo, Widjang Herry

    1975-01-01

    The role of phosphorus sources in the growth of lowland rice plant was studied using P 32 -labelled superphosphate. The experiment was carried out in the glass house. Three high yielding rice varieties used in the experiment were PB 5, IR 22 and Pelita I/1. Results obtained from the experiment showed that, during early growth, seedlings in the nursery did not require any phosphorus from outside. The phosphorus needed was apparently supplied by the seeds themselves. After 10 days seedlings started using phosphorus from outside the plants. Phosphorus in the plants derived from fertilizer reached 5-12% at 16 days old and 25-40% at transplanting time depending on the varieties. Higher response to phosphorus application in the nursery was given by Pelita I/1, the phosphorus in the plants derived from fertilizer was 40% at transplanting time. The phosphorus requirement was mostly supplied by the application of phosphorus fertilizer till 20 days after transplanting but after 40 days soil-phosphorus became the main source for the plants. (author)

  20. Characterization of plant-derived carbon and phosphorus in lakes by sequential fractionation and NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shasha [College of Water Sciences, Beijing Normal University, Beijing 100875 (China); State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Zhu, Yuanrong, E-mail: zhuyuanrong07@mails.ucas.ac.cn [State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Wu, Fengchang, E-mail: wufengchang@vip.skleg.cn [State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Meng, Wei [State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); He, Zhongqi [USDA-ARS Southern Regional Research Center, 1100 Robert E Lee Blvd, New Orleans, LA 70124 (United States); Giesy, John P. [State Key Laboratory of Environment Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Department of Biomedical and Veterinary Biosciences and Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan (Canada)

    2016-10-01

    Although debris from aquatic macrophytes is one of the most important endogenous sources of organic matter (OM) and nutrients in lakes, its biogeochemical cycling and contribution to internal load of nutrients in eutrophic lakes are still poorly understood. In this study, sequential fractionation by H{sub 2}O, 0.1 M NaOH and 1.0 M HCl, combined with {sup 13}C and {sup 31}P NMR spectroscopy, was developed and used to characterize organic carbon (C) and phosphorus (P) in six aquatic plants collected from Tai Lake (Ch: Taihu), China. Organic matter, determined by total organic carbon (TOC), was unequally distributed in H{sub 2}O (21.2%), NaOH (29.9%), HCl (3.5%) and residual (45.3%) fractions. For P in debris of aquatic plants, 53.3% was extracted by H{sub 2}O, 31.9% by NaOH, and 11% by HCl, with 3.8% in residual fractions. Predominant OM components extracted by H{sub 2}O and NaOH were carbohydrates, proteins and aliphatic acids. Inorganic P (P{sub i}) was the primary form of P in H{sub 2}O fractions, whereas organic P (P{sub o}) was the primary form of P in NaOH fractions. The subsequent HCl fractions extracted fewer species of C and P. Some non-extractable carbohydrates, aromatics and metal phytate compounds remained in residual fractions. Based on sequential extraction and NMR analysis, it was proposed that those forms of C (54.7% of TOC) and P (96.2% of TP) in H{sub 2}O, NaOH and HCl fractions are potentially released to overlying water as labile components, while those in residues are stable and likely preserved in sediments of lakes. These results will be helpful in understanding internal loading of nutrients from debris of aquatic macrophytes and their recycling in lakes. - Highlights: • Sequential fractionation combined with NMR analysis was applied on aquatic plants. • Labile and stable C and P forms in aquatic plants were characterized. • 54.7% of OM and 96.2% of P in aquatic plants are potentially available. • 45.3% of OM and 3.8% of P in aquatic