WorldWideScience
1

On stochastic approximation algorithms for classes of PAC learning problems  

Energy Technology Data Exchange (ETDEWEB)

The classical stochastic approximation methods are shown to yield algorithms to solve several formulations of the PAC learning problem defined on the domain [o,1]{sup d}. Under some assumptions on different ability of the probability measure functions, simple algorithms to solve some PAC learning problems are proposed based on networks of non-polynomial units (e.g. artificial neural networks). Conditions on the sizes of these samples required to ensure the error bounds are derived using martingale inequalities.

1994-03-01

2

HyPac french platform on the hydrogen and fuel cells; HyPac plateforme francaise sur l'hydrogene et les piles a combustible  

Energy Technology Data Exchange (ETDEWEB)

HyPac is a french platform on the hydrogen and fuel cells applications, created in 2008. the authors presents the opportunities of the french platform HyPac, the objectives, the participants and the budget. (A.L.B.)

2008-07-01

3

Spectroscopy of "1"0"1Mo by sub-Coulomb stripping  

International Nuclear Information System (INIS)

... deuteron beams differential cross sections dwba excitation functions mev range

4

Synthesis and characterization of Rosebengal/folicacid-functionalized multiwall carbon nanotubes  

British Library Electronic Table of Contents (United Kingdom)

Multiwall carbon nanotubes (MWCNTs) were functionalized with a photosensitizer, rosebengal (RB), and folicacid (FA), an anti-cancer drug simultaneously and individually, which was characterized with various analytical instruments like Fourier Transform Iinfrared (FTIR) spectroscopy, UV?Vis spectroscopy, Thermogravimetric analysis (TGA), Photoluminescence (PL) spectroscopy, X-ray photoelectron spectroscopy (XPS), and Transmission electron microscopy (TEM). FTIR spectra confirmed the chemical modification of MWCNT. The chemical functionalization of MWCNT with RB was further supported by UV?Vis and PL spectra.

2011-01-01

5

Functional pools of oxidative and glycolytic fibers in human muscle observed by 31P magnetic resonance spectroscopy during exercise.  

UK PubMed Central (United Kingdom)

Quantitative probing of heterogeneous regions in muscle is feasible with phosphorus-31 magnetic resonance spectroscopy because of the differentiation of metabolic patterns of glycolytic and oxidative...Full Text Available

1987-12-01

6

Amorphous to crystalline phase transformation in Metglas reg-sign studied by Moessbauer spectroscopy  

International Nuclear Information System (INIS)

The authors present differential scanning calorimetry (DSC) and in situ Moessbauer spectroscopy results for Metglas ribbons, to which different heat treatments were made. The Curie temperature of the amorphous phase is determined and the evolution of the magnetic field of this phase is studied as a function of temperature

1997-12-01

7

Presence of two independent chromosomes in the Brucella melitensis 16M genome.  

UK PubMed Central (United Kingdom)

Mapping the restriction fragments of the Brucella melitensis 16M genome with a new restriction endonuclease, PacI, which cut the DNA into only eight fragments, indicated that this species contains two...Full Text Available

1993-02-01

8

NOAA ESRL Marine and Air-Sea Interaction Working Group  

Science.gov (United States)

Climate Observations Joint Air-Sea Monsoon Investigation: JASMINE Nauru '99 NTAS PACS SHEBA STRATUS VOCALS WHOTS Data Cruises Tropical Eastern Pacific Synthesis The Research...

2011-10-15

9

Body image and explicit and implicit anti-fat attitudes: the mediating role of physical appearance comparisons.  

Science.gov (United States)

Prejudice against overweight people is rife. However, there is a paucity of research on the underlying reasons for it. In two studies the relationship between body image, the tendency to make physical appearance-related comparisons (PACS), and both explicit and implicit anti-fat attitudes was examined. In Study 1 (n = 227) people with a high tendency to make physical appearance-related comparisons (high PACS scorers) reported lower self-appearance evaluation, but higher appearance orientation and explicit anti-fat attitudes. The PACS fully mediated the relationship between appearance orientation and explicit anti-fat attitudes. Study 2 (n = 134) found that the PACS also mediated the relationship between appearance orientation and implicit anti-fat attitudes. Thus, individual differences in factors such as body image and the tendency to make appearance-related comparisons, appear to play a central role ...

2007-07-24

10

Biosynthesis and Uptake of Siderophores Is Controlled by the PacC-Mediated Ambient-pH Regulatory System in Aspergillus nidulans  

UK PubMed Central (United Kingdom)

Biosynthesis and uptake of siderophores in Aspergillus nidulans are regulated not only by iron availability but also by ambient pH: expression of this high-affinity iron uptake system...Full Text Available

2004-04-01

11

A Picture Archiving and Communication System Module for Radiology  

UK PubMed Central (United Kingdom)

This paper presents the design and implementation of a clinical picture archiving and communication system (PACS) module within the radiology department of a 700-bed teaching hospital. The system is...Full Text Available

1988-11-09

12

Bragg curve spectroscopy  

CERN Document Server

Bragg curve spectroscopy

1981-01-01

13

Tunneling spectroscopy of anisotropic superconductors  

Energy Technology Data Exchange (ETDEWEB)

Tunneling spectroscopy of normal-insulator-superconductor junction is investigated theoretically. In anisotropic superconductors, differently from the case of isotropic superconductor, the effective pair potentials felt by quasiparticles depend on the direction of their motion. By taking this effect into account, it is shown that the conductance spectra strongly depend on the crystal orientation. Using Green`s function method, local density of states (LDOS) in superconductor is also calculated. The close relation between conductance spectra and LDOS is presented. The calculation is compared with experimental spectra of high-{Tc} superconductors.

1996-12-31

14

Subseabed disposal: systematic application of the site qualification plan  

Energy Technology Data Exchange (ETDEWEB)

Two criteria, geologic stability and barrier effectiveness, form the basis of the Subseabed Disposal Program's site qualification plan to evaluate the ocean basins and identify those regions having characteristics most favorable for containment of radioactive waste. Stability criteria are used to define those regions least likely to be disturbed by tectonic forces or oceanographic changes during the lifetime of a waste repository. Barrier criteria define those lithologies most likely to form an effective barrier to the release of radionuclides. Two north Pacific regions and three north Atlantic regions (PAC I and II and ATL I, II, and III, respectively) have thus far been selected for further investigation based on the site qualification plan. The PAC I region, centered on the Shatsky Rise in the northwest Pacific, has been subdivided into areas and locations on the basis of an exhaustive review of data available in the archives of ...

1982-01-01

15

Ensemble quantum computing by NMR?spectroscopy  

UK PubMed Central (United Kingdom)

A quantum computer (QC) can operate in parallel on all its possible inputs at once, but the amount of information that can be extracted from the result is limited by the phenomenon of wave function...Full Text Available

1997-03-04

16

Human cDNA mapping using fluorescence in situ hybridization. Final progress report, April 1, 1994--July 31, 1997  

Energy Technology Data Exchange (ETDEWEB)

The ultimate goal of this research is to generate and apply novel technologies to speed completion and integration of the human genome map and sequence with biomedical problems. To do this, techniques were developed and genome-wide resources generated. This includes a genome-wide Mapped and Integrated BAC/PAC Resource that has been used for gene finding, map completion and anchoring, breakpoint definition and sequencing. In the last period of the grant, the Human Mapped BAC/PAC Resource was also applied to determine regions of human variation and to develop a novel paradigm of primate evolution through to humans. Further, in order to more rapidly evaluate animal models of human disease, a BAC Map of the mouse was generated in collaboration with the MTI Genome Center, Dr. Bruce Birren.

1997-12-31

17

Localisation of the neuropeptide PACAP and its receptors in the rat parathyroid and thyroid glands.  

Science.gov (United States)

PACAP (pituitary adenylate cyclase activating polypeptide) is widely distributed neuropeptide acting via three subtypes of receptors, PAC(1), VPAC(1) and VPAC(2). Here we examined the localisation and nature of PACAP-immunoreactive nerves in the rat thyroid and parathyroid glands and defined the distribution of PAC(1), VPAC(1) and VPAC(2) receptor mRNA's. In the parathyroid gland a large number of nerve fibres displaying PACAP-immunoreactivity were distributed beneath the capsule, around blood vessels and close to glandular cells. Most of the PACAP-nerves were sensory, since they co-stored CGRP (calcitonin-gene-related peptide) and were sensitive to capsaicin-treatment. mRNA's for PAC(1) and VPAC(2) receptors occurred in the parathyroid gland, mainly located in the glandular cells. In the thyroid gland PACAP-immunoreactive nerve fibres were associated with blood vessels, thyroid follicles and parafollicular C-cells. A high ...

2010-12-19

18

Electron momentum density measurements by means of positron annihilation and Compton spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The electron momentum density is measured applying positron annihilation and Compton spectroscopy in order to get information about electron wave functions. Compton spectroscopic measurements of Pd-Ag and Cu-Zn alloy systems are carried out taking into account crystal structure, mixability, and order state. Three-dimensional momentum densities of silicon are determined in order to get better information about its electronic structure. The momentum density and the spin density of ferromagnetic nickel are investigated using angular correlation curves.

1982-01-01

19

A fast model for estimating work-function modifications induced by organic charge-transfer (Sub)monolayers  

Energy Technology Data Exchange (ETDEWEB)

Calculating work-function modifications for flat-lying conjugated molecules on extended metal surfaces using density functional theory (DFT) is an extremely resource intensive task. This prevents fast screening of new molecules for their potential to optimize metal work functions for good electron or hole injection in organic electronic devices. We present a semi-classical model, which avoids that problem. This is achieved by identifying the dominant processes occurring at the interface between metal and adsorbate in the pinning-regime, which are then parameterizing their description using band-structure DFT calculations for a small training set With the resulting interdependent equations at hand, only simple gas-phase calculations are needed to predict the work-function changes induced by new molecules. The model is tested for ten molecules on three different metal surfaces, where it shows excellent ...

2010-07-01

20

Impedance Noise Identification for State-of-Health Prognostics  

Energy Technology Data Exchange (ETDEWEB)

Impedance Noise Identification is an in-situ method of measuring battery impedance as a function of frequency using a random small signal noise excitation source. Through a series of auto- and cross-correlations and Fast Fourier Transforms, the battery complex impedance as a function of frequency can be determined. The results are similar to those measured under a lab-scale electrochemical impedance spectroscopy measurement. The lab-scale measurements have been shown to correlate well with resistance and power data that are typically used to ascertain the remaining life of a battery. To this end, the Impedance Noise Identification system is designed to acquire the same type of data as an on-board tool. A prototype system is now under development, and results are being compared to standardized measurement techniques such as electrochemical impedance spectroscopy. A brief description of the Impedance ...

2008-07-01

21

Fourier transform IR studies on the interaction of selected chemicals with isolated cuticles  

International Nuclear Information System (INIS)

It is known that the plant cuticle represents the first barrier that must be overcome by any chemical reaching the plant surface from the atmosphere before entering the plant. Because of the importance of the cuticle as a barrier to penetration of a wide variety of compounds, its morphology, chemistry, and permeability have been extensively studied. However, only limited information is available on the nature of functional chemical groups present and their interaction and role during the penetration process. The usefulness of in situ Fourier transform infrared spectroscopy studies in identifying functional groups present in isolated cuticles is described and their relationships to the structure of the cuticular membrane are discussed. Applications of infrared spectroscopy on the presence and role of phenolics in the cuticle structure and during the cuticle development, nitrogen oxide binding to isolated ...

22

Bonding and microstructural stability in Ni55Ti45 studied by experimental and theoretical methods  

Energy Technology Data Exchange (ETDEWEB)

Spiral orbit tribometry friction tests performed on Ni-rich Ni55Ti45 titanium ball bearings indicate that this alloy is a promising candidate for future aerospace bearing applications. Microstructural characterization of the bearing specimens was performed using transmission electron microscopy and energy dispersive spectroscopy, with NiTi, Ni4Ti3, Ni3Ti, and Ni2Ti4Ox phases identified within the microstructure of the alloy. Density functional theory was applied to predict the electronic structure of the NixTiy phases, including the band structure and site projected density of states. Ultraviolet photoemission spectroscopy was used to verify the density of states results from the density functional theory calculations, with good agreement observed between experiment and theory.

2010-11-25

23

Calibration free laser-induced breakdown spectroscopy of oxide materials  

Energy Technology Data Exchange (ETDEWEB)

The quantitative determination of oxide concentration by laser-induced breakdown spectroscopy is relevant in various fields of applications (e.g.: analysis of ores, concrete, slag). Calibration free laser-induced breakdown spectroscopy and the multivariate calibration are among the methods employed for quantitative concentration analysis of complex materials. We measured the intensity of neutral and ionized atomic emission lines of oxide materials by laser-induced breakdown spectroscopy and we modified the calibration free laser-induced breakdown spectroscopy method to increase the accuracy. The concentration of oxides was obtained by using stoichiometric relations. Sample materials were prepared from oxide powder (Fe{sub 2}O{sub 3}, MgO, CaO) by mixing and pressing. The concentration was 9.8-33.3 wt.% Fe{sub 2}O{sub 3}, 7.6-33.3 wt.% MgO and 33.3-81.2 wt.% CaO for different samples. Nd:YAG laser ...

2010-08-15

24

In-situ IR reflexion spectroscopy characterization of the passivation layer developed on the surface of lithium electrodes in organic medium; Passivation de surface: une nouvelle voie pour reduire l`autodecharge dans les batteries rechargeables a ions lithium LiMn{sub 2}O{sub 4}/Li  

Energy Technology Data Exchange (ETDEWEB)

the development of lithium metal batteries is hindered by the bad reversibility of the Li{sup +}/Li pair, due to dendrites formation which limits the amount of active matter and can generate short-circuits. The chemical and electrochemical phenomena which take place at the electrode/organic electrolyte interface lead to the formation of a complex passivation film which is of prime importance for the functioning of this type of batteries. The in-situ infrared reflection spectroscopy is well adapted to the chemical study of the passivation layer. Two different techniques were used: the substraction normalized interfacial transform infrared spectroscopy (SNIFTIRS) and the electro-chemically modulated infrared reflectance spectroscopy. These methods have shown that the passivation layer that develops on the surface of the lithium electrode in contact with organic solutions (propylene carbonate, ethylene ...

1996-12-31

25

Generalized functions  

CERN Document Server

Generalized functions

1967-01-01

26

Generalized functions  

CERN Document Server

Generalized functions

1964-01-01

27

Sol-gel coatings with phosphonate functionalities for surface modification of magnesium alloys  

International Nuclear Information System (INIS)

Hybrid organic-inorganic coatings with phosphonate functionalities have been synthesized and evaluated as prospective surface treatments for magnesium materials. These coatings have been processed via a sol-gel route by hydrolysis and condensation of a mixture of diethylphosphonatoethyltriethoxy-silane and tetraethoxy-silane with variable molar ratios. The coatings morphology and the surface chemistry at the coating/substrate interface have been characterized using scanning electron microscopy, X-ray photoelectron spectroscopy, "3"1P nuclear magnetic resonance spectroscopy, and time-of-flight secondary ion mass spectrometry. The corrosion protection performance of the coatings deposited on magnesium alloy AZ31B has been examined by a group of electrochemical techniques including potentiodynamic polarization and electrochemical impedance spectroscopy. In addition, a scanning Kelvin probe technique has ...

2006-08-30

28

Electron temperature diagnostics in the RFX reversed field pinch experiment  

Energy Technology Data Exchange (ETDEWEB)

The paper presents an integrated approach to the problem of electron temperature diagnostics of the plasma in a reversed field pinch. Three different methods, sampling different portions of the electron distribution function, are adopted, namely Thomson scattering, soft X-ray spectroscopy by pulse-height analysis and filtered soft X-ray intensity ratio. A careful analysis of the different sources of systematic errors is performed and a novel statistical approach is adopted to mutually validate the three independent measurements. A satisfactory agreement is obtained over a large range of experimental conditions, indicating that in the plasma core the energy distribution function is well represented by a maxwellian. (author)

2000-08-01

29

EFFECTS OF PH AND PHOSPHATE ON METAL DISTRIBUTION WITH EMPHASIS ON AS SPECIATION AND MOBILIZATION IN SOILS FROM A LEAD SMELTING SITE  

Science.gov (United States)

Arsenic in soils from the Asarco Lead Smelter in East Helena, Montana was characterized by X-ray absorption spectroscopy (XAS). As oxidation state and geochemical speciation were analyzed as a function of depth (two sampling sites) and surface distribution. These results were c...

30

Bragg-curve spectroscopy at high rates  

Energy Technology Data Exchange (ETDEWEB)

The performance of a Bragg ionization chamber has been investigated as a function of the counting rate with approx.= 5 MeV/amu /sup 32/S beams: up to approx.= 20 kHz the energy resolution is below 0.9% and the Z resolving power is more than 50. (orig.).

1986-03-01

31

Removal of tetracycline and sulfonamide classes of antibiotic compound by powdered activated carbon  

Energy Technology Data Exchange (ETDEWEB)

Removal of sulfonamide (SAs) and tetracycline (TAs) classes of antibiotic compound from deionized water and DOC water by powdered activated carbon (PAC) adsorption was evaluated in this study. According to the study results, TAs were more easily adsorbed than SAs although TAs were more hydrophilic than SAs. The phenolic compounds in TAs might be responsible for their high adsorption. Complex formation of TAs with metal and metal oxide on the surface of activated carbon might also contribute to higher adsorption. The hydrophobic effect was important for removal of SAs. More hydrophobic SAs were removed more easily. The carbon type was not important for adsorption of SAs and TAs. Coal based carbon and coconut based carbon showed similar removal efficiencies for these antibiotics. Dissolved organic materials interfered with adsorption of SAs and TAs. Organic interference was more significant for the antibiotic compound, which was more subject to the ...

2008-03-15

32

Infinite-parametric extension of the conformal algebra in D>2 space-time dimensions  

International Nuclear Information System (INIS)

On the basis of the analytic continuations of semisimple Lie algebras discovered recently by us we construct manifestly quasiconformal infinite-dimensional algebras AC(so(4, 1)) and PAC(so(3, 2)) extending the conformal algebras in three-dimensional euclidean and Minkowski space-time like the Virasoro algebra extends so(2, 1). Their higher spin generalizations are also constructed. A counterpart of the central extension for D > 2 and possible appplications in exactly solvable conformal quantum field models in D > 2 are discussed. (orig.).

1991-01-01

33

Chiral and Continuum Extrapolation of Partially-Quenched Hadron Masses  

CERN Document Server

Using the finite-range regularisation (FRR) of chiral effective field theory, the chiral extrapolation formula for the vector meson mass is derived for the case of partially-quenched QCD. We re-analyse the dynamical fermion QCD data for the vector meson mass from the CP-PACS collaboration. A global fit, including finite lattice spacing effects, of all 16 of their ensembles is performed. We study the FRR method together with a naive polynomial approach and find excellent agreement ~1% with the experimental value of M_rho from the former approach. These results are extended to the case of the nucleon mass.

2005-01-01

34

A numerical study of expected accuracy and precision in Calibration-Free Laser-Induced Breakdown Spectroscopy in the assumption of ideal analytical plasma  

Energy Technology Data Exchange (ETDEWEB)

Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS) has been proposed several years ago as an approach for quantitative analysis of Laser-Induced Breakdown Spectroscopy spectra. Recently developed refinement of the spectral processing method is described in the present work. Accurate quantitative results have been demonstrated for several metallic alloys. However, the degree of accuracy that can be achieved with Calibration-Free Laser-Induced Breakdown Spectroscopy analysis of generic samples still needs to be thoroughly investigated. The authors have undertaken a systematic study of errors and biasing factors affecting the calculation in the Calibration-Free Laser-Induced Breakdown Spectroscopy spectra processing. These factors may be classified in three main groups: 1) experimental aberrations (intensity fluctuations and inaccuracy in the correction for spectral efficiency of a detection ...

2007-12-15

35

A numerical study of expected accuracy and precision in Calibration-Free Laser-Induced Breakdown Spectroscopy in the assumption of ideal analytical plasma  

International Nuclear Information System (INIS)

Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS) has been proposed several years ago as an approach for quantitative analysis of Laser-Induced Breakdown Spectroscopy spectra. Recently developed refinement of the spectral processing method is described in the present work. Accurate quantitative results have been demonstrated for several metallic alloys. However, the degree of accuracy that can be achieved with Calibration-Free Laser-Induced Breakdown Spectroscopy analysis of generic samples still needs to be thoroughly investigated. The authors have undertaken a systematic study of errors and biasing factors affecting the calculation in the Calibration-Free Laser-Induced Breakdown Spectroscopy spectra processing. These factors may be classified in three main groups: 1) experimental aberrations (intensity fluctuations and inaccuracy in the correction for spectral efficiency of a detection ...

2007-12-01

37

Point contact Andreev reflection spectroscopy of NdFeAsO_0_._8_5  

International Nuclear Information System (INIS)

The newly discovered oxypnictide family of superconductors show very high critical temperatures of up to 55 K. Whilst there is growing evidence that suggests a nodal order parameter, point contact Andreev reflection spectroscopy can provide crucial information such as the gap value and possibly the number of energy gaps involved. For the oxygen deficient NdFeAsO_0_._8_5 with a T_c of 45.5 K, we show that there is clearly a gap value at 4.2 K that is of the order of 7 meV, consistent with previous studies on oxypnictides with lower T_c. In addition, taking the spectra as a function of gold tip contact pressure reveals important changes in the spectra which may be indicative of more complex physics underlying this structure. (rapid communication)

2008-09-01

38

DBD Surface Modification of Polymers in Relation to the Spatial Distribution of Reactive Oxygen Species  

British Library Electronic Table of Contents (United Kingdom)

The homogeneity of a helium dielectric barrier discharge, working at atmospheric pressure and containing oxygen as contaminant, is assessed by mapping the spatial distribution of oxygen metastable atoms in relation to the uniformity of surface properties. Tunable diode laser absorption spectroscopy is used to monitor the time evolution of the absorption coefficient corresponding to the oxygen metastable atoms on the 35S2 level, as a function of the laser absorbing path, whereas bi-dimensional Abel transform is used to obtain local information on the space distribution of the metastable atoms in the discharge. The radial distribution of the surface properties is investigated using atomic force microscopy, contact angle measurement and X-ray photoelectron spectroscopy. The results show that ...

2011-01-01

39

Functionalizing titania nanoparticle surfaces in a fluidized bed plasma reactor  

International Nuclear Information System (INIS)

Functionalizing nanoparticle surfaces is essential for achieving homogeneous dispersions of monodisperse particles in polymer nanocomposites for successful utilization in engineering applications. Functionalization reduces the surface energy of the nanoparticles, thereby limiting the tendency to agglomerate. Moreover, reactive groups on the surface can also participate in the polymerization, creating covalent bonds between the inorganic and organic phases. In this paper, a fluidized bed inductively coupled plasma (FB-ICP) reactor is used to break apart the agglomerates and functionalize commercial TiO2 nanoparticle powders in a batch of several grams. The fluidized bed could be implemented into a continuous flow reactor, potentially making this a viable method to treat larger quantities of commercial powders. The particles are treated with acrylic acid (AA) and tetraethylorthosilicate (TEOS) plasma and the ...

2009-11-18

40

Alpha-induced reactions in iridium  

Energy Technology Data Exchange (ETDEWEB)

The excitation function of ({alpha},{ital xn}) reactions on {sup 191}Ir (abundance 37.3%) and on {sup 193}Ir (abundance 62.7%) has been measured for the 17--55 MeV alpha-particle bombarding energy range. The stacked foil activation technique and {gamma}-ray spectroscopy were used to determine the cross sections. The experimental data were compared with calculated values obtained by means of a geometry-dependent hybrid model. The initial exciton number {ital n}{sub 0}=4 with {ital n}=2, {ital p}=2, and {ital h}=0 gives the best agreements with the presently measured results. To calculate the excitation function theoretically a computer code was used. This set of excitation functions provides a data basis for probing the validity of combined equilibrium and preequilibrium reaction models in a considerable energy range.

1992-05-01

41

Use of real-time Fourier Transform Infrared Reflectivity as an in situ monitor of YBCO film growth and processing  

CERN Document Server

Fourier Transform Infrared (FTIR) spectroscopy has been utilized during high rate E-beam evaporation/deposition of YBa2Cu3O7 (YBCO). The results demonstrate the great utility of FTIR as an in situ monitor of YBCO deposition and processing. We detect different (amorphous/fine polycrystalline) insulating pre-existing phases to the high Tc superconducting phase which appear to have distinct reflectivity fingerprints dominated by thin film interference effects, as a function of temperature and oxygen pressure. These fingerprints reveal some of the kinetic and thermodynamic pathways during the growth of YBCO.

2007-01-01

42

Phytic acid doped nanoparticles for green anticorrosion coatings  

British Library Electronic Table of Contents (United Kingdom)

In this paper, an environmentally friendly metal corrosion inhibitor, phytic acid, was assembled into the walls of silica nanoparticles via layer-by-layer self-assembly technique (LbL) with poly(allylamine hydrochloride). Such functionalized nanoparticles were uniformly distributed into sol-gel films for metal anticorrosion. The films showed very pronounced and lasting protective efficiency in concentrated salt aqueous solutions as indicated by electrochemical impedance spectroscopy (EIS) measurement. These results may provide a new route for the preparation of environment-friendly anticorrosion coatings.

2010-01-01

43

In vivo magnetic resonance techniques and drug discovery  

International Nuclear Information System (INIS)

The long and resource intensive process of drug discovery and development is confronted with the basic challenge of providing effective and safe therapies at reasonably low costs. The better the mechanism of a disease is known, the higher the probability to find an appropriate therapy. Also, the better and earlier a disease can be diagnosed and characterized, the higher the chance to be able to interfere in this process with a chemical entity. This reasoning sets the framework for the use of imaging in drug discovery. We discuss the relevance of magnetic resonance imaging and spectroscopy to derive anatomical, functional, metabolic and target-related information in the context of pharmacological research in vivo. (author)

2006-03-01

44

Analyzing Morphology and Thermal History of Polybutylene Terephthalate by THz Time-domain Spectroscopy  

British Library Electronic Table of Contents (United Kingdom)

We have measured the frequency-dependent dielectric function of semi-crystalline polybutylene terephthalate (PBT) in the terahertz region between 100?GHz and approximately 2.8?THz. A characteristic band is observed around 2.38?THz. The intensity of this band is a good indicator of the degree of crystallinity of the different samples. A potential assignment of this band is proposed, based on the comparison with spectroscopic data of the structurally very similar polyethylene terephtalate (PET). Furthermore, the frequency-dependent index of refraction of PBT reveals more insight about the morphology and different thermal history of the samples under investigation.

2011-01-01

45

Synthesis, crystal structure, spectroscopic properties, antibacterial activity and theoretical studies of a novel difunctional acylhydrazone  

British Library Electronic Table of Contents (United Kingdom)

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

2011-01-01

46

Spectroscopy and photophysics of mono methyl-substituted alloxazines  

Energy Technology Data Exchange (ETDEWEB)

Singlet-singlet and triplet-triplet absorption spectra of a series of methyl-alloxazines were calculated using the time-dependent density-functional theory approach and compared to experimental results. The B3LYP functional provides good correlation between experimental and theoretical results, given that solvent effects are disregarded in the present calculations. Substituent and solvent dependences of the lowest, closely spaced, n,{pi}* and {pi},{pi}* excited state energies are discussed, their order being of consequence in determining the non-radiative decay rates and thus emission quantum yields and lifetimes. The high quantum yields of singlet oxygen formation indicate that the triplet state is formed by efficient intersystem crossing from the first singlet excited state.

2004-05-31

47

PET/MRI hybrid imaging: devices and initial results  

British Library Electronic Table of Contents (United Kingdom)

The combination of functional and morphological imaging technologies such as positron emission tomography (PET) and X-ray computed tomography (CT) has shown its value in the clinical and preclinical field. However, CT provides only very limited soft-tissue contrast and exposes the examined patient or laboratory animal to a high X-ray radiation dose. In comparison to CT, magnetic resonance tomography (MRI) provides excellent soft-tissue contrast and allows for nuclear magnetic resonance spectroscopy (NMRS) or functional MRI (fMRI). Thus, the combination of PET and MRI has been pursued for several years. First approaches have succeeded using conventional photo multiplier tube (PMT) technology together with light fibers to transfer scintillation light away from the high magnetic field. Latest...

2008-01-01

48

A PAC containing the human mitochondrial DNA polymerase gamma gene (POLG) maps to chromosome 15q25  

Energy Technology Data Exchange (ETDEWEB)

The human mitochondrial DNA (mtDNA) is a closed circular, 16,569-bp double-stranded DNA, encoding 13 genes whose protein products are subunits of the oxidative phosphorylation system required for synthesis of most of the ATP consumed by eukaryotic cells. Point mutations of the mtDNA that cause multi-tissue, loss-of-energy syndromes, called mitochondrial encephalomyopathies (e.g., MERRF and MELAS), have been identified. In addition, large-scale deletions of the human mtDNA have been identified and are the molecular bases for the neonatal and adolescent onset loss-of-energy syndromes Pearson and Kearns-Sayer, respectively. 5 refs., 1 fig.

1997-03-01

54

Spectroscopy, colorimetry, and biological chemistry in the nineteenth century.  

UK PubMed Central (United Kingdom)

The development of colorimetry and spectroscopy in the nineteenth century is described. An account is given of the application of their techniques to biological chemistry during that period.

1981-03-01

55

Resonance ionization spectroscopy at {sup 240f,242f}Am fission isomers  

Energy Technology Data Exchange (ETDEWEB)

Optical Isotope shift measurements have been performed for the {sup 240f,242f}Am fission isomers to test the stability of nuclear deformation as function of the neutron number. The method is based on resonance ionization spectroscopy (RIS) in a buffer gas cell with fission detection of the ionization process. The {sup 240f,242f}Am fission isomers have been produced by {sup 242}Pu(p, 3n), {sup 242}Pu(d, 2n) reactions, respectively. Relative isotope shift ratios X{sub exp}{sup 242f}(500 nm)=IS{sup 242f,241}/IS{sup 243,241}=41.4(8) and X{sub exp}{sup 240f}(500 nm)=IS{sup 240f,241}/IS{sup 243,241}=39.2(8) were measured. From these ratios a small difference {delta}{beta}{sub 2}{sup 242f,240f}=0.0076(14) of the deformation parameter {beta}{sub 2} can be deduced assuming that the isotope shift between the reference isotopes {sup 241,243}Am is caused by a pure volume change. (orig.)

1997-10-01

56

Non-thermal atmospheric pressure HF plasma source: generation of nitric oxide and ozone for bio-medical applications  

International Nuclear Information System (INIS)

A new miniature high-frequency (HF) plasma source intended for bio-medical applications is studied using nitrogen/oxygen mixture at atmospheric pressure. This plasma source can be used as an element of a plasma source array for applications in dermatology and surgery. Nitric oxide and ozone which are produced in this plasma source are well-known agents for proliferation of the cells, inhalation therapy for newborn infants, disinfection of wounds and blood ozonation. Using optical emission spectroscopy, microphotography and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined for varied nitrogen/oxygen flows. The influence of the gas flows on the plasma conditions is studied. Ozone and nitric oxide concentrations in the effluent of the plasma source are measured using absorption spectroscopy and electro-chemical ...

2010-01-01

57

High resolution alpha-particle spectroscopy using CR-39 plastic track detector  

Energy Technology Data Exchange (ETDEWEB)

A technique has been developed for high resolution alpha particle spectroscopy from track length determination in CR-39 plastic. On individual tracks an energy resolution deltaE close to the range straggling limit is obtainable. For 6 MeV alpha-particle deltaE is proportional 35 keV on individual particles and for groups of particles deltaE proportional 20 keV can be achieved using certain data selection criteria. At 100 keV on individual particles deltaE is proportional 20 keV. The analysis requires 1) a knowledge of the track-etch rate (Vsub(T))-range relationship and 2) a theoretical understanding of alpha-particle track structure in CR-39 as a function of particle energy, dip angle and degree of etching. The structure of alpha-particle etched tracks in CR-39 is described and two methods of analysis discussed. Examples are given of the resolution attainable on tracks of alpha-particles as natural decay energy and from alpha-particles ...

1984-06-15

58

Follow up of the functioning of a lithium-polymer battery using confocal Raman micro-spectroscopy; Suivi du fonctionnement d`un accumulateur lithium-polymere par microspectrometrie Raman confocale  

Energy Technology Data Exchange (ETDEWEB)

The confocal Raman micro-spectroscopy has been used for the study of a Lithium/polymer electrolyte-LiTFSI/V{sub 2}O{sub 5} type battery in which the polymer electrolyte thickness is of about 80 {mu}m. The analysis is performed on the side of the battery thanks to a specially designed cell which preserves all the characteristics of the real system. The analysis is performed on 20 points aligned between the anode and the cathode and with a depth of several tenth of {mu}m. The analysis of data obtained during charging/output cycles allows to evaluate the gradients of salt concentration inside the electrolyte, the pollutions of LiOH, Li{sub 2}CO{sub 3}, Li{sub 2}O and Li{sub 3}N -type at the lithium interface, but also the structural modifications of the cathode material. The in-situ study of concentration gradients inside the electrolyte is of prime importance for the understanding of dendrites growth. (J.S.) 11 refs.

1996-12-31

59

Deposition of plasma-polymerized hydroxyethyl methacrylate (HEMA) on silicon in presence of argon plasma  

International Nuclear Information System (INIS)

2-hydroxyethyl methacrylate (HEMA) has been deposited onto the surface of silicon substrate (thickness = 500 ?m) using plasma polymerization technique. Polymerization process was carried out in an in-house developed inductively coupled plasma polymerization setup. The depositions were carried out using RF power supply (13.56 MHz) at power of 75 W for 10 and 40 min. The RF supply was coupled to the inductance through a matching network. The effect of plasma polymerization (surface grafting) on the degree of surface modification has been investigated. The chemical changes on the polymer backbone are followed from the results of Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS), which show the peaks corresponding to the functional groups of the HEMA polymerized onto the silicon surface. The morphology of the modified surfaces has also been investigated using scanning electron microscopy ...

2005-05-30

60

Crystal field and EPR studies of Nd{sup 3+}:YMO{sub 4}(M=V,AS,P)  

Energy Technology Data Exchange (ETDEWEB)

Crystal field calculation and electron paramagnetic resonance (EPR) have been performed on zircon-type materials Nd:YMO{sub 4} (M=V, As, P). Simulation of the energy level schemes has been carried out and the wave functions composition and g tensor principal values associated to the first sub-level of the {sup 4}I{sub 9/2} manifold were calculated. A rather good correlation is obtained between crystal field calculations and the EPR measurements. Furthermore, some extra lines observed by optical spectroscopy (absorption and emission) also appear on the EPR spectra and a correlation between the two spectroscopies indicates that Nd{sup 3+}-Nd{sup 3+} exchange and dipolar interactions occur in the zircon family, even at very low doping content (less than 8 x 10{sup 19} Nd{sup 3+} ions cm{sup -3}). Nd{sup 3+}-Nd{sup 3+} pairs at distances 3.9, 5.9 and 6.3 A have been identified. (orig.) 13 refs.

1998-07-24

61

Crystal field and EPR studies of Nd"3"+:YMO_4(M=V,AS,P)  

International Nuclear Information System (INIS)

Crystal field calculation and electron paramagnetic resonance (EPR) have been performed on zircon-type materials Nd:YMO_4 (M=V, As, P). Simulation of the energy level schemes has been carried out and the wave functions composition and g tensor principal values associated to the first sub-level of the "4I_9_/_2 manifold were calculated. A rather good correlation is obtained between crystal field calculations and the EPR measurements. Furthermore, some extra lines observed by optical spectroscopy (absorption and emission) also appear on the EPR spectra and a correlation between the two spectroscopies indicates that Nd"3"+-Nd"3"+ exchange and dipolar interactions occur in the zircon family, even at very low doping content (less than 8 x 10"1"9 Nd"3"+ ions cm"-"3). Nd"3"+-Nd"3"+ pairs at distances 3.9, 5.9 and 6.3 A have been identified. (orig.)

1998-07-24

62

Composition Dependence of the Photocatalytic Activities of BiOCl1-xBrx Solid Solutions under Visible Light  

British Library Electronic Table of Contents (United Kingdom)

Abstract We prepared BiOCl1-xBrx (x=0-1) solid solutions and characterized their structures, morphologies, and photocatalytic properties by X-ray diffraction, diffuse reflectance spectroscopy, scanning electron microscopy, Raman spectroscopy, photocurrent and photocatalytic activity measurements and also by density functional theory calculations for BiOCl, BiOBr, BiOCl0.5Br0.5. Under visible-light irradiation BiOCl1-xBrx exhibits a stronger photocatalytic activity than do BiOCl and BiOBr, with the activity reaching the maximum at x=0.5 and decreasing gradually as x is increased toward 1 or decreased toward 0. This trend is closely mimicked by the photogenerated current of BiOCl1-xBrx, indicating that the enhanced photocatalytic activity of BiOCl1-xBrx with respect to those of BiOCl and BiO...

2011-01-01

63

An investigation of the capacitance dispersion on the fractal carbon electrode with edge and basal orientations  

Energy Technology Data Exchange (ETDEWEB)

Capacitance dispersion on the fractal carbon electrode with edge and basal orientations was investigated using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and a.c.-impedance spectroscopy. For this purpose, four types of as-received pyrolytic graphite electrode, as-received, mechanically polished, and as-activated glassy carbon electrodes were prepared with different surface irregularities and amounts of edge orientations. The apparent self-similar fractal dimensions of the carbon electrodes were determined from the analyses of AFM images based upon triangulation method. The amounts of edge orientations on the surface of the carbon electrodes were qualitatively estimated from the XPS analysis of surface acidic functional groups that were preferably formed on the edge planes by the heat treatment of the carbon electrodes. The values of the constant phase element exponent {alpha} determined from the ...

2003-10-15

64

A comparative study of natural, formaldehyde-treated and copolymer-grafted orange peel for Pb(II) adsorption under batch and continuous mode  

Energy Technology Data Exchange (ETDEWEB)

Natural, formaldehyde-treated and copolymer-grafted orange peels were evaluated as adsorbents to remove lead ions from aqueous solutions. The optimum pH for lead adsorption was found to be pH 5. The adsorption process was fast, reaching 99% of sorbent capacity in 10 min for the natural and treated biomasses and 20 min for the grafted material. The treated biomass showed the highest sorption rate and capacity in the batch experiments, with the results fitting well to a pseudo-first order rate equation. In the continuous test with the treated biomass, the capacity at complete exhaustion was 46.61 mg g{sup -1} for an initial concentration of 150 mg L{sup -1}. Scanning electronic microscopy and energy dispersive X-ray spectroscopy indicated that the materials had a rough surface, and that the adsorption of the metal took place on the surface. Fourier transform infrared spectroscopy revealed that the functional groups ...

2009-01-30

65

Structure and Function Evolution of Thiolate Monolayers on Gold  

Energy Technology Data Exchange (ETDEWEB)

The use of n-alkanethiolate self-assembled monolayers on gold has blossomed in the past few years. These systems have functioned as models for common interfaces. Thiolate monolayers are ideal because they are easily modified before or after deposition. The works contained within this dissertation include interfacial characterization (inbred reflection absorption spectroscopy, ellipsometry, contact angle, scanning probe microscopy, and heterogeneous electron-transfer kinetics) and various modeling scenarios. The results of these characterizations present ground-breaking insights into the structure, function, and reproducible preparation of these monolayers. Surprisingly, three interfacial properties (electron-transfer, contact angle, and ellipsometry) were discovered to depend directly on the odd-even character of the monolayer components. Molecular modeling was utilized to investigate adlayer orientation, and suggests that ...

2006-05-01

66

Tuning the spin state of iron phthalocyanine by ligand adsorption  

International Nuclear Information System (INIS)

The future use of single-molecule magnets in applications will require the ability to control and manipulate the spin state and magnetization of the magnets by external means. There are different approaches to this control, one being the modification of the magnets by adsorption of small ligand molecules. In this paper we use iron phthalocyanine supported by an Au(111) surface as a model compound and demonstrate, using x-ray photoelectron spectroscopy and density functional theory, that the spin state of the molecule can be tuned to different values (S #approx# 0, 1/2, 1) by adsorption of ammonia, pyridine, carbon monoxide or nitric oxide on the iron ion. The interaction also leads to electronic decoupling of the iron phthalocyanine from the Au(111) support. (fast track communication)

2010-12-01

67

Temperature and time-dependence of the elastic moduli of Pu and Pu-Ga alloys  

International Nuclear Information System (INIS)

In previous work, on cooling from 300 K to 10 K the elastic moduli for both #alpha#- and #delta#-Pu dropped 30%. This large change may reflect effects of 5f-electron localization. In this work, the elastic moduli at ambient temperature of several Pu-Ga alloys were measured using resonant ultrasound spectroscopy (RUS). The strong temperature dependence of the bulk and shear modulus and the temperature independence of Poisson's ratio was confirmed and the upper temperature limit for #alpha#-Pu was extended to 360 K. Measurements of the time dependence of the shear moduli of Pu and Pu-2.36 at.% Ga were determined with high precision as a function of time and temperature. Using a model for time dependence of point defects, we determined the exponential time constant at ambient temperature for such variations. The low temperature results are consistent with Fluss .

2007-10-11

68

Polyester and multiwalled carbon nanotube composites: characterization, electrical conductivity and antibacterial activity  

British Library Electronic Table of Contents (United Kingdom)

Abstract Poly(butylene terephthalate) (PBT) composites containing multiwalled carbon nanotubes (MWCNTs) were prepared using a melt-blending process and used to examine the effects on the composite structure and properties of replacing PBT with acrylic acid-grafted PBT (PBT-g-AA). PBT-g-AA and multihydroxyl-functionalized MWCNTs (MWCNTs-OH) were used to improve the compatibility and dispersibility of the MWCNTs within the PBT matrix. The composites were characterized morphologically using transmission electron microscopy, and chemically using Fourier transform infrared, solid-state 13C NMR and UV-visible absorption spectroscopy. The antibacterial and electrical conductivity properties of the composites were also evaluated. MWCNTs or MWCNTs-OH enhanced the antibacterial activity and electric...

2011-01-01

69

Oxidation of polycaprolactone to induce compatibility with other degradable polyesters  

British Library Electronic Table of Contents (United Kingdom)

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

2007-01-01

70

Layer-by-layer assembly of functional silica and Au nanoparticles for fabricating electrogenerated chemiluminescence sensor  

Energy Technology Data Exchange (ETDEWEB)

We described the use of silica nanoparticles as building blocks for the immobilization of electrogenerated chemiluminescence (ECL) reagent Ru(bpy){sub 3}{sup 2+} and the fabrication of layer-by-layer assembly film by alternating the deposition of the Ru(bpy){sub 3}{sup 2+}-doped silica nanoparticles and Au nanoparticles. UV-vis absorption spectroscopy, scanning electron microscopy (SEM), cyclic voltammetry and ECL were used to characterize the uniform growth of the multilayer film. Since Ru(bpy){sub 3}{sup 2+} could still maintain its ECL property when doped into the silica nanoparticles, the as-prepared multilayer film could be used as an effective ECL sensor, and the sensor showed high sensitivity and good stability.

2008-09-20

71

Layer-by-layer assembly of functional silica and Au nanoparticles for fabricating electrogenerated chemiluminescence sensor  

International Nuclear Information System (INIS)

We described the use of silica nanoparticles as building blocks for the immobilization of electrogenerated chemiluminescence (ECL) reagent Ru(bpy)_3"2"+ and the fabrication of layer-by-layer assembly film by alternating the deposition of the Ru(bpy)_3"2"+-doped silica nanoparticles and Au nanoparticles. UV-vis absorption spectroscopy, scanning electron microscopy (SEM), cyclic voltammetry and ECL were used to characterize the uniform growth of the multilayer film. Since Ru(bpy)_3"2"+ could still maintain its ECL property when doped into the silica nanoparticles, the as-prepared multilayer film could be used as an effective ECL sensor, and the sensor showed high sensitivity and good stability.

2008-09-20

72

Layer-by-layer assembly of functional silica and Au nanoparticles for fabricating electrogenerated chemiluminescence sensor  

British Library Electronic Table of Contents (United Kingdom)

We described the use of silica nanoparticles as building blocks for the immobilization of electrogenerated chemiluminescence (ECL) reagent Ru(bpy)32+ and the fabrication of layer-by-layer assembly film by alternating the deposition of the Ru(bpy)32+-doped silica nanoparticles and Au nanoparticles. UV-vis absorption spectroscopy, scanning electron microscopy (SEM), cyclic voltammetry and ECL were used to characterize the uniform growth of the multilayer film. Since Ru(bpy)32+ could still maintain its ECL property when doped into the silica nanoparticles, the as-prepared multilayer film could be used as an effective ECL sensor, and the sensor showed high sensitivity and good stability.

2008-01-01

73

Kramers-Kronig Analysis of Infrared Reflectance Spectra for Quaternary In_xAl_yGa_1_-_x_-_yN Alloy  

International Nuclear Information System (INIS)

In this paper, a Kramers-Kronig (KK) analysis of infrared (IR) reflectance spectrum of quaternary In_0_._0_1Al_0_._0_6Ga_0_._9_3N film grown by molecular beam epitaxy (MBE) is reported. The infrared measurement is performed in the reflection mode at an incident angle of 15 degree sign by Fourier transform infrared (FTIR) spectroscopy at T = 300 K. The Kramers-Kronig analysis of the reflectivity data has been used to obtain the real and imaginary parts of the index of refraction (n and k), and the real and imaginary parts of the dielectric response function (#epsilon#' and #epsilon#') of the materials. Finally, the transverse optical and longitudinal optical phonons for quaternary In_xAl_yGa_1_-_x_-_yN were obtained.

2010-07-07

74

Exploring the binding of the strong organic acceptor F{sub 4}TCNQ to coinage metals  

Energy Technology Data Exchange (ETDEWEB)

Organic/metal interface properties are of high interest for the application of molecular (sub)monolayers to modify surface properties. They are applied for, e.g., molecular electronics, chemical sensing, or the tuning of injection barriers in organic electronic devices. We present a joint theoretical and experimental study of F{sub 4}TCNQ adsorbed on Cu(111). The electronic and structural properties were determined by ultraviolet photoelectron spectroscopy (UPS) and X-ray standing wave (XSW) measurements. To better understand the complex process of binding, we modelled the system using density-functional theory. We find forward-donation from the lone pairs of the molecule into metallic states and back-donation from the metal into the LUMO of the molecule. The data on Cu(111) are compared to F4TCNQ on Au(111) and Ag(111) as well as to investigations of pyrenetetraone on various coinage metals.

2008-07-01

75

Effect of material aging on parachute pack life: a synopsis of Sandia National Laboratories studies  

Energy Technology Data Exchange (ETDEWEB)

A systematic study of the effects of environmental factors on nylon 66 and Kevlar 29 strength degradation in parachute components is being conducted at Sandia National Laboratories. It includes: (1) accelerated aging studies in air, inert environments, humidity, ozone, and smog; (2) a 25-year surveillance program of parachutes in a variety of natural climatic environments; (3) moisture absorption as a function of humidity; (4) effects of surface coatings normally applied to parachutes; and (5) development of nondestructive evaluation techniques which can be used to map mechanical properties over the entire parachute surface. The accelerated aging and moisture absorption studies show that air, humidity, and smog contribute to degradation. Chemiluminescence, gas chromatographic pyrograms, and uv spectroscopy show promise as nondestructive evaluation techniques.

1984-01-01

76

Degradation of the corrosion resistance of anodic oxide films through immersion in the anodising electrolyte  

Energy Technology Data Exchange (ETDEWEB)

The deterioration of AA2024, AA6061 and AA7475 anodised in an environmentally-compliant tartaric acid/sulphuric acid electrolyte has been examined as a function of the immersion time in the electrolyte after termination of anodising. By transmission electron microscopy and scanning electron microscopy, degradation of the porous oxide film was qualitatively observed on AA2024. Electrochemical impedance spectroscopy revealed that AA2024 and AA7075 were more sensitive to prolonged immersion in the anodising electrolyte compared with AA6061, due to increased barrier layer thinning rates and increased susceptibility to localized corrosion. Salt spray tests confirmed the previous, indicating decay of anticorrosion performance for AA2024 and AA7075.

2010-07-15

77

Cluster model for lattice distortion effects on electronic structure: VO and VO_2  

International Nuclear Information System (INIS)

Molecular cluster predictions for electronic energy levels, wave functions, momentum densities, and Compton profiles of VO and VO_2 are examined within the Hartree-Fock-Slater model. VO_6 clusters are treated in O/subh/, D_4/subh/, and D_2/subh/ symmetry to obtain quantitative relations between distortion parameters and level shifts and splittings. Effects of the crystal environment are taken into account by a potential field. Results for VO are consistent with the augmented plane-wave band calculation of Mattheiss and x-ray emission data; the VO_2 levels are in good agreement with x-ray photoelectron spectroscopy data. A sizable anisotropy is predicted for the Compton profile of VO and VO_2.

78

Cationic cyclization of purified natural rubber in latex form with a trimethylsilyl triflate as a novel catalyst  

British Library Electronic Table of Contents (United Kingdom)

Cyclization of deproteinized natural rubber (DPNR) or purified natural rubber latex was effectively performed in latex phase by using trimethylsilyl-trifluoromethane sulfonate or trimethylsilyl triflate (TMSOTF) as a novel catalyst, which is still not reported in the case of natural rubber latex. Various cyclization conditions affecting the degree of cyclization were studied, such as dry rubber contents, temperature, TMSOTF concentrations, and time. The cyclized products were characterized by FTIR, Raman, 1H-, and 13C-NMR spectroscopies, as well as DSC and TGA. The degree of cyclization was estimated by 1H-NMR spectrum. It was found that the degree of cyclization in NR was a function of cyclization conditions. The thermal stability of cyclized DPNR increased with the degree of cyclization....

2007-01-01

79

Bandgap properties of the indium sulfide thin-films grown by co-evaporation  

British Library Electronic Table of Contents (United Kingdom)

In the present study the optical properties of co-evaporated indium sulfide thin films are investigated. Before being optically characterized, the composition as well as the crystalline properties of the film have been checked with the help of energy dispersive spectroscopy (EDX) and X-Ray diffraction (XRD) analyses. The optical absorption coefficient ? of this indium sulfide film has been deduced from reflectivity R(?) and transmission T(?) measurements. The fit of the curve representing ?(h?) suggests that the ?-In2S3 has an indirect bandgap of 2.01?eV. Density functional theory (DFT) calculations are performed on this indium sulfide compound, using TB-LMTO code. Through these band structure investigations, an indirect bandgap is predicted as observed experimentally. The top of the valen...

2009-01-01

80

Andreev reflection spectroscopy in MgB{sub 2}  

Energy Technology Data Exchange (ETDEWEB)

Our Andreev reflection measurements (Phys. Rev. Lett. 87 (2001) 137005) along with other experiments have led to a general consensus that MgB{sub 2} is a multiband superconductor with two main superconducting gaps closing at the same T{sub c}. Here we show the behavior of the small gap as a function of the temperature and magnetic field. This gap is isotropic with T{sub c} of the bulk material but with a specific small (crossover) critical magnetic field of about 1 T much lower than the real H{sub c2}. The latter field is anisotropic and is rather governed by the large gap and strongly anisotropic Fermi surface of the material.

2003-04-01

81

The effect of oxygen in Ru gate electrode on effective work function of Ru/HfO2 stack structure  

British Library Electronic Table of Contents (United Kingdom)

Effective work function (m,eff) values of Ru gate electrode on SiO2 and HfO2 MOS capacitors were carefully examined and discussed from the viewpoint of an effect of oxygen incorporation in Ru gate electrode on m,eff. Annealing at 400degreeC in the reduction (3%H2) and the oxidation (1%O2) ambient resulted in similar changes in the m,eff of Ru/HfO2/SiO2 and Ru/SiO2 MOS capacitors. Furthermore, the Ru gate MOS capacitor after annealing in the oxidation condition have shown almost the same m,eff value to that of RuO2 gate MOS capacitors. The oxygen concentration in the Ru/HfO2 interface after annealing in oxidizing atmosphere is approximately one order of magnitude higher than that after annealing in reducing atmosphere as confirmed by secondary ion mass spectroscopy analysis. Furthermore, th...

2006-01-01

82

Synchrotron PES and NEXAFS studies of self-assembled aromatic thiol monolayers on Au(1 1 1)  

Energy Technology Data Exchange (ETDEWEB)

Self-assembled monolayers (SAMs) on various metal, semiconductor or insulator substrates can be easily modified with specific functional groups of interest and have promising applications in surface wetting (hydrophobic/hydrophilic modification), tribology, corrosion protection, sensor electrodes modification, molecular and biomolecular recognition, protein adsorption, cell adhesion, and molecular- or organic-electronic device fabrications. In this paper, we highlight recent progress in the development of SAMs on solid substrates as well as their practical applications, with particular emphasis on the characterization of self-assembled aromatic thiol monolayers with different functional groups on Au(1 1 1) using synchrotron-based photoemission spectroscopy and near-edge X-ray absorption fine structure measurements. The SAM-related molecular orientation, electronic structures, and chemical bonding are presented. Using ...

2009-05-15

83

Self-consistent relativistic density-functional theory: Application to neutral uranium atom and some ions of lithium isoelectronic sequence  

Science.gov (United States)

In a relativistic density-functional theory the importance of the transverse photon contribution to the exchange potential in the high-density regime is pointed out. A neutral atom /sup 92/U is studied and its orbital energies calculated in the present scheme are compared with previous calculations based on relativistic Hartree, Dirac-Slater, and Dirac-Fock schemes and with experimental values from (electron spectroscopy for chemical analysis) ESCA studies. The present scheme is also used to calculate the orbital and total energies of some highly stripped ions of the Li isoelectronic sequence which occur as impurities in controlled thermonuclear plasma. These energies are found to be in close agreement with more involved Dirac-Fock results. Also, the relativistic effects significantly increase in going from C/sup 3 +/ to W/sup 71 +/ because the electronic density reaches values for which relativistic effects become large.

1980-07-01

84

PET/MRI hybrid imaging: devices and initial results  

International Nuclear Information System (INIS)

The combination of functional and morphological imaging technologies such as positron emission tomography (PET) and X-ray computed tomography (CT) has shown its value in the clinical and preclinical field. However, CT provides only very limited soft-tissue contrast and exposes the examined patient or laboratory animal to a high X-ray radiation dose. In comparison to CT, magnetic resonance tomography (MRI) provides excellent soft-tissue contrast and allows for nuclear magnetic resonance spectroscopy (NMRS) or functional MRI (fMRI). Thus, the combination of PET and MRI has been pursued for several years. First approaches have succeeded using conventional photo multiplier tube (PMT) technology together with light fibers to transfer scintillation light away from the high magnetic field. Latest PET/MRI developments use solid-state light detectors that can be operated even at high magnetic fields. Initial pilot studies with ...

2008-06-01

85

Mechanism of biosorption of Heavy metals by mucor rouxii  

Energy Technology Data Exchange (ETDEWEB)

Fungi such as Aspergillus niger and Mucor rouxii are capable of removing heavy metals from aqueous solutions. The role various functional groups play in the cell wall of M. rouxii in metal biosorption of lead, cadmium, nickel and zinc was investigated in this paper. The biomass was chemically treated to modify the functional carboxyl, amino and phosphate groups. These modifications were examined by means of infrared spectroscopy. It was found that an esterification of the carboxyl groups and phosphate and a methylation of the amine groups significantly decreased the biosorption of the heavy metals studied. Thus, the carboxylate, amine and phosphate groups were recognized as important in the biosorption of metal ions by M. rouxii biomass. The role the lipids fraction play was not significant. The study showed that Na, K, Ca and Mg ions were released from the biomass after biosorption of Pb,Cd,Ni and Zn, indicating that ion ...

2008-08-15

86

Measurement and analysis of alpha particle induced reactions on praseodymium  

International Nuclear Information System (INIS)

Excitation functions (EFs) for the reaction "1"4"1Pr(#alpha#, n)"1"4"4Pm and "1"4"1Pr(#alpha#, 2n)"1"4"3Pm have been measured using "1"4"1Pr as a target up to 50 MeV #alpha#-particle energy. Stacked foil activation technique and #gamma#-ray spectroscopy using 100 cm"3 Ge (Li) detector, has been used. Excitation functions are also calculated theoretically using Blann's geometry dependent hybrid (GDH) model code ALICE-91, with and without inclusion of pre-equilibrium particle emission. It has been observed that high-energy tails of the EFs are dominated by pre-equilibrium reaction mechanism. With the accepted set of input parameter, initial exciton number n_0=4 (2p + 2n + 0h), a good qualitative agreement is found. However, quantitative agreement for this magic nucleus"1"4"1Pr is also good when theoretical calculations are normalized by a multiple factor of 0.5. (author)

2005-04-01

87

Chemical imaging of wood-polypropylene composites.  

Science.gov (United States)

Recent investigations of wood plastic composites have revealed a detrimental effect of using lubricant systems in production. This includes nullifying part or all of the mechanical benefit of using a polar compatibilizer, maleic anhydride polypropylene (MAPP), in the composite formulation. This investigation utilizes lubricants labeled with deuterium in conjunction with Fourier transform infrared (FT-IR) spectroscopy to allow for the separation of individual lubricants from all other material constituents. All of the deuterium labeled lubricants, used without MAPP, revealed their expulsion from the wood interface during crystallization. MAPP coupling agent was found to exist near the wood, but it is unclear if any covalent bonding with the hydroxyl functionality on the wood surface occurred. The addition of zinc stearate lubricants appears to nullify the activity of the anhydride functionality near the wood surface as ...

2006-08-01

88

A structural and corrosion study of triethoxysilyl and perfluorooctyl functionalized polyhedral silsesquioxane nanocomposite films on AA 2024 alloy  

International Nuclear Information System (INIS)

A tri-functional polyhedral oligomeric silsesquioxane (POSS) based silane precursor R_xR_yR_z(SiO_3_/_2)_n (x + y + z = n = 6, 8, 10, ...) bearing 3-(N-(3-triethoxysilylpropyl)ureido)propyl, isooctyl and perfluoropropyl groups was synthesized and investigated as corrosion protective coating for AA 2024 alloy. Infrared reflection-absorption (IR RA) combined with X-ray photoelectron spectroscopy and atomic force microscopy provided information about partial self-assembling of coatings having a fluorine enriched upper layer with a low surface energy (#gamma#"t"o"t = 12.37 mN/m). The structural changes that accompanied corrosion produced under chronocoulometrical conditions were assessed from ex-situ IR RA spectra. A new band at 1690-1700 cm"-"1 appeared above the corrosion potential, and was assigned to the formation of amidonium ions and consequent relaxation of urea-urea associations.

2010-03-01

89

Modification of ink-jet paper by oxygen-plasma treatment  

International Nuclear Information System (INIS)

A study on oxygen-plasma treatment of ink-jet paper is presented. Paper was exposed to a weakly ionized, highly dissociated oxygen plasma with an electron temperature of 5 eV, a positive-ion density of 8 x 1015 m-3 and a density of neutral oxygen atoms of 5 x 1021 m-3. Optical emission spectroscopy (OES) was applied as a method for detection of the reaction products during the plasma treatment of the paper. OES spectra between 250 and 1000 nm were measured continuously during the plasma treatment. The wettability of the samples before and after the plasma treatment was determined by measuring the contact angle of a water drop. The appearance of the surface-functional groups was determined by using high-resolution x-ray photoelectron spectroscopy (XPS), while changes in the surface morphology were monitored with scanning electron microscopy (SEM). Already after 1 s of the plasma treatment the surface, which was originally ...

2007-06-21

90

CR portal imaging; A linac graphy using storage phosphor imaging systems  

Energy Technology Data Exchange (ETDEWEB)

In portal images with high energy X-ray (10 MV), it is sometimes difficult to verify the irradiation field because of the low contrast. Especially, in the abdominal and pelvic region, the deterioration of portal image quality is remarkable. To solve this problem, we took portal images using computed radiography (FCR). Also, we develop a technique in which a copper plate (3 mm) and lead foil (0.3 mm) are closely set in the front and rear of the photostimulable phosphor plate (imaging plate), for increased energy absorption. As a result, image quality was very high and we confirmed image improvement using observer performance experiments. We made a special cassette which can closely set metallic plates to imaging plate and load FCR-7000 directly. Therefore, image process becomes simple, and suitable for routine work. In computed radiography, image processing (tone scale modification and edge enhancement) is possible, and is advantageous portal imaging. When PACS is ...

1992-07-01

91

CR portal imaging  

International Nuclear Information System (INIS)

In portal images with high energy X-ray (10 MV), it is sometimes difficult to verify the irradiation field because of the low contrast. Especially, in the abdominal and pelvic region, the deterioration of portal image quality is remarkable. To solve this problem, we took portal images using computed radiography (FCR). Also, we develop a technique in which a copper plate (3 mm) and lead foil (0.3 mm) are closely set in the front and rear of the photostimulable phosphor plate (imaging plate), for increased energy absorption. As a result, image quality was very high and we confirmed image improvement using observer performance experiments. We made a special cassette which can closely set metallic plates to imaging plate and load FCR-7000 directly. Therefore, image process becomes simple, and suitable for routine work. In computed radiography, image processing (tone scale modification and edge enhancement) is possible, and is advantageous portal imaging. When PACS is ...

1992-01-01

92

Optical Spectroscopy for Noninvasive Monitoring of Stem Cell Differentiation  

UK PubMed Central (United Kingdom)

There is a requirement for a noninvasive technique to monitor stem cell differentiation. Several candidates based on optical spectroscopy are discussed in this review: Fourier transform infrared (FTIR)...Full Text Available

2010-01-01

93

On the spectroscopy of quantum dots in microcavities  

Energy Technology Data Exchange (ETDEWEB)

At the occasion of the OECS conference in Madrid, we give a succinct account of some recent predictions in the spectroscopy of a quantum dot in a microcavity that remain to be observed experimentally, sometimes within the reach of the current state of the art.

2010-02-01

94

Molecular spectroscopy and planetary atmospheres  

Energy Technology Data Exchange (ETDEWEB)

With the improvements accomplished during the past 15 years in detection techniques and instrumentation and with the opening of space exploration, molecular spectroscopy has become a very efficient way to probe planetary atmospheres.

1984-01-01

95

Kinetic and equilibrium characterization of uranium(VI) adsorption onto carboxylate-functionalized poly(hydroxyethylmethacrylate)-grafted lignocellulosics.  

Science.gov (United States)

This study investigated the feasibility of using a new adsorbent prepared from coconut coir pith, CP (a coir industry-based lignocellulosic residue), for the removal of uranium [U(VI)] from aqueous solutions. The adsorbent (PGCP-COOH) having a carboxylate functional group at the chain end was synthesized by grafting poly(hydroxyethylmethacrylate) onto CP using potassium peroxydisulphate-sodium thiosulphite as a redox initiator and in the presence of N,N'-methylenebisacrylamide as a crosslinking agent. IR spectroscopy results confirm the graft copolymer formation and carboxylate functionalization. XRD studies confirm the decrease of crystallinity in PGCP-COOH compared to CP, and it favors the protrusion of the functional group into the aqueous medium. The thermal stability of the samples was studied using thermogravimetry (TG). Surface charge density of the samples as a function of ...

2008-01-28

96

Reference standard for carbonaceous impurity measurements in carbon nanotubes  

Science.gov (United States)

Near-infrared spectroscopy is a convenient tool for measuring nanotube / carbonaceous impurities

2004-01-01

97

Quality engineering and control semiannual progress report November and December 1976 and January--April 1977  

International Nuclear Information System (INIS)

Research and development activities are reported on absorption spectroscopy, calorimetry, electrolysis, emission spectroscopy, fluorimetry gas chromatography, infrared spectroscopy, liquid chromatography, liquid scintillation counting, mass spectroscopy, microscopy, radiometric analysis, and thermal analysis. A group of miscellaneous projects are also described.

107

A Leptonic-Hadronic Model for the Afterglow of Gamma-Ray ...  

Science.gov (United States)

... PHYSICS ATOMIC AND MOLECULAR PHYSICS AND SPECTROSCOPY NUCLEAR PHYSICS & ELEMENTARY PARTICLE PHYSICS. ...

2010-11-20

108

Time-resolved confocal fluorescence spectroscopy reveals the structure and metabolic state of epithelial tissue  

Science.gov (United States)

Autofluorescence spectroscopy has been a widely explored technique for in vivo and noninvasive diagnosis of pre-cancer lesions in epithelium where 90% cancers originate. For extracting more accurate fluorescence information for cancer diagnosis, depth-resolved fluorescence measurements are crucial to assess NADH and FAD in non-keratinized epithelial layer and collagen in stromal layer, respectively. In this study, we achieved the depth-resolved fluorescence spectral measurements of squamous epithelial tissue based on confocal technique. We found that in non-keratinized epithelial layer the fluorescence signals excited at 405 nm were the combination of NADH and FAD fluorescence and could be used for evaluating the redox ratio. Moreover, we found that confocal time-resolved autofluorescence measurements of epithelial tissue with 405 nm excitations could provide the information on the layered tissue structure. All depth-resolved autofluorescence decays were accurately ...

2007-03-01

109

Reactive biomolecular divergence in genetically altered yeast cells and isolated mitochondria as measured by biocavity laser spectroscopy : a rapid diagnostic method for studying cellular responses to stress and disease.  

Energy Technology Data Exchange (ETDEWEB)

We report an analysis of four strains of baker's yeast (Saccharomyces cerevisiae) using biocavity laser spectroscopy. The four strains are grouped in two pairs (wild type and altered), in which one strain differs genetically at a single locus, affecting mitochondrial function. In one pair, the wild-type rho+ and a rho0 strain differ by complete removal of mitochondrial DNA (mtDNA). In the second pair, the wild-type rho+ and a rho- strain differ by knock-out of the nuclear gene encoding Cox4, an essential subunit of cytochrome c oxidase. The biocavity laser is used to measure the biophysical optic parameter Deltalambda, a laser wavelength shift relating to the optical density of cell or mitochondria that uniquely reflects its size and biomolecular composition. As such, Deltalambda is a powerful parameter that rapidly interrogates the biomolecular state of single cells and mitochondria. Wild-type cells and mitochondria produce ...

2006-12-01

110

Raman Under Nitrogen. The High-Resolution Raman Spectroscopy of Crystalline Uranocene, Thorocene, and Ferrocene  

Science.gov (United States)

The utility of recording Raman spectroscopy under liquid nitrogen, a technique we call Raman Under Nitrogen (RUN), is demonstrated for ferrocene, uranocene and thorocene. Using RUN, low temperature (liquid nitrogen cooled) Raman spectra for these compounds exhibit higher resolution than previous studies and new vibrational features are reported. The first Raman spectra of crystalline uranocene at 77 K are reported using excitation from argon (5145 ) and krypton (6764 ) ion lasers. The spectra obtained showed bands corresponding to vibrational transitions at 212, 236, 259, 379, 753, 897, 1500, and 3042 cm-1 , assigned to ring-metal-ring stretching, ring-metal tilting, out-of-plane CCC bending, in-plane CCC bending, ring-breathing, C-H bending, CC stretching and CH stretching, respectively. The assigned vibrational bands are compared to those of uranocene in THF and thorocene. All vibrational frequencies of the ligands, except the 259 cm-1 out-of-plane CCC bending ...

2004-02-08

111

Raman Under Nitrogen. The High-Resolution Raman Spectroscopy of Crystalline Uranocene, Thorocene, and Ferrocene  

International Nuclear Information System (INIS)

The utility of recording Raman spectroscopy under liquid nitrogen, a technique we call Raman Under Nitrogen (RUN), is demonstrated for ferrocene, uranocene and thorocene. Using RUN, low temperature (liquid nitrogen cooled) Raman spectra for these compounds exhibit higher resolution than previous studies and new vibrational features are reported. The first Raman spectra of crystalline uranocene at 77 K are reported using excitation from argon (5145 ) and krypton (6764 ) ion lasers. The spectra obtained showed bands corresponding to vibrational transitions at 212, 236, 259, 379, 753, 897, 1500, and 3042 cm-1 , assigned to ring-metal-ring stretching, ring-metal tilting, out-of-plane CCC bending, in-plane CCC bending, ring-breathing, C-H bending, CC stretching and CH stretching, respectively. The assigned vibrational bands are compared to those of uranocene in THF and thorocene. All vibrational frequencies of the ligands, except the 259 cm-1 out-of-plane CCC bending ...

2004-02-08

112

Point-contact Andreev-reflection spectroscopy in MgB{sub 2}: The role of substitutions  

Energy Technology Data Exchange (ETDEWEB)

We summarize the results of point-contact Andreev-reflection (PCAR) spectroscopy in MgB{sub 2} doped by chemical substitutions, either magnetic (Mn) or non-magnetic (Al,C), obtained by us and by other groups in the last four years. Despite the variety of samples used (crystals and polycrystals of various origin) and some minor differences in the experimental techniques, these measurements have directly provided a complete and consistent picture of the effects of chemical substitutions on the gaps of MgB{sub 2} shedding light on other relevant parameters (scattering rates, DOSs) affected by doping. In Al-doped crystals and polycrystals, the gap amplitudes {delta}{sub {sigma}} and {delta}{sub {pi}} - obtained through a two-band Blonder-Tinkham-Klapwijk (BTK) fit of the Andreev-reflection conductance curves - decrease on increasing the Al content x (i.e. on decreasing the critical temperature of the contacts T{sub c}{sup A}), but remain clearly distinct with no ...

2007-06-01

113

In situ spectroscopic and corrosion studies of ultra-thin gradient plasma polymer layers on zinc  

International Nuclear Information System (INIS)

By means of an audio frequency plasma polymerisation ultra-thin gradient plasma polymer layers were deposited on zinc and zinc-coated iron. The aim was to generate an interfacial polymeric layer which bonds to an oxidised metal as well as to a subsequently applied organic coating and acts as an interfacial barrier layer for ions and water. Surface modifications were done in an in situ plasma cell with infrared reflection absorption spectroscopy (IRRAS). The zinc surface was first activated by an oxygen plasma to provide a freshly oxidised and contamination free oxide surface. The intermediate stages of the surface reactions could be revealed. Carbon dioxide molecules as oxidation products adsorbed on the growing zinc oxide and were desorbed at a later stage. An organosilicon plasma polymer was deposited directly on top of the oxide layer from a hexamethyldisilane (HMDS) plasma. Afterwards a cyclohexene (CHEX)/hexamethyldisilane co-plasma polymer was deposited. The ...

2003-07-15

115

Chemometric study of functional groups in Pennsylvanian gymnosperm plant organs (Sydney Coalfield, Canada): Implications for chemotaxonomy and assessment of kerogen formation  

Energy Technology Data Exchange (ETDEWEB)

The samples comprise the foliage of four pteridosperm-medullosalean plant fossil species of differing preservation states and one of a cordaitean species from two Canadian Maritime sub-basins of Carboniferous age (300 Ma; Sydney and Stellarton coalfields, Nova Scotia, respectively). Included in the sample set were some coal samples from Sydney Coalfield, along with published data for coal macerals for comparison. By applying Schulze's maceration process to the fossil foliage to obtain the cuticles, five sample forms evolved, viz. compressions, cuticles and fossilized cuticles, and acidic and alkaline solutions from Schulze's process, to which was added the Sydney coal samples as the sixth form. Area integration of the absorbance spectra from solid and liquid state Fourier transform infrared (FTIR) spectroscopy, produced functional chemical parameters which were organized into a data matrix of eight variables and 62 samples (8 ...

2010-12-15

116

Water Repellency Microstructure Oligomer Formulation Cured with Electron Beam  

International Nuclear Information System (INIS)

Water repellency en the microstructure super-hydrophobic cured surface is important for research and industrial purposes. This microstructure film can be cured on polyethylene terephthalate PET surface by electron beam (EB) at different irradiation doses 10-100 kGy. The microstructure formulation composed from hydrophobic acrylate oligomer (EB 244) and monomer (SR 440). The irradiation induced cross linking of the prepared microstructure was proved by FTIR spectroscopy and the adhesion force by abrasion test. Some factors affecting the adhesion force of the prepared microstructure film such as oligomer/monomer composition ratio and the thickness of the microstructure cured film were studied. The contact angles (8) were measured on cured surfaces before and after adding the super hydrophobic nanoparticles (Zonyl 9361). The super-hydrophobic cured surface showed the self-cleaning property. The volume of water droplet affected both the observed contact angle and its ...

117

Use of lanthanide shift reagents with [sup 31]P FT-NMR spectroscopy to analyze concentrated lake-water samples  

Energy Technology Data Exchange (ETDEWEB)

Several lanthanide shift reagents (LSR) were synthesized from praseodymium, europium, dysprosium, and terbium using ethylenediaminetetraacetic acid, trans-1,2-diaminocyclohexane-N,N,N[prime],N[prime]-tetraacetic acid, and diethylenetriaminepentaacetic acid for the purpose of separating overlapping [sup 31]P FT-NMR spectral signals of dissolved organic phosphorus compounds present in concentrated lake-water samples. The extent of change in signal position and line width of several known phosphorus compounds dissolved in pure water was examined as a function of solution pH and the molar ratio of LSR to phosphorus. Praseodymium ethylenediaminetetraacetate (PrEDTA) was determined to be the most effective LSR. Concentrated lake-water samples mixed with PrEDTA were examined with [sup 31]P FT-NMR. The use of PrEDTA provided separation of overlapping signals, indicated that phosphorus compounds were becoming isolated from the solution environment during sample ...

1994-08-01

118

Two-nucleon multiplets near mass A = 88 and the implication for the residual nucleon-nucleon interaction  

Energy Technology Data Exchange (ETDEWEB)

The low excitation energy spectroscopy of /sup 86/Sr, /sup 88/Sr, /sup 89/Sr, /sup 86/Rb, and /sup 87/Rb nuclear systems was studied via one-nucleon transfer reactions. The strontium isotopes, /sup 87/Sr and /sup 88/Sr, were used as targets in this study. Spectroscopic strengths were extracted from the measured transfer reaction cross sections and the distorted wave Born approximation (DWBA) analysis. Efforts have been made to accomplish a complete detection of spectroscopic strengths through the excitation energy region where levels can be resolved and identified. A shell model sum rule analysis is then made. Diagonal matrix elements for the effective two-nucleon interaction were deduced from empirical energy centroid. Matrix elements normalized by their empirical monopole energy was plotted against the semiclassical angle between two spins. They were compared with various analytical function forms of the effective two-nucleon interaction ...

1987-01-01

119

Two-nucleon multiplets near mass A = 88 and the implication for the residual nucleon-nucleon interaction  

International Nuclear Information System (INIS)

The low excitation energy spectroscopy of "8"6Sr, "8"8Sr, "8"9Sr, "8"6Rb, and "8"7Rb nuclear systems was studied via one-nucleon transfer reactions. The strontium isotopes, "8"7Sr and "8"8Sr, were used as targets in this study. Spectroscopic strengths were extracted from the measured transfer reaction cross sections and the distorted wave Born approximation (DWBA) analysis. Efforts have been made to accomplish a complete detection of spectroscopic strengths through the excitation energy region where levels can be resolved and identified. A shell model sum rule analysis is then made. Diagonal matrix elements for the effective two-nucleon interaction were deduced from empirical energy centroid. Matrix elements normalized by their empirical monopole energy was plotted against the semiclassical angle between two spins. They were compared with various analytical function forms of the effective two-nucleon interaction depending on their spins, ...

120

The effect of boron implant energy on transient enhanced diffusion in silicon  

Energy Technology Data Exchange (ETDEWEB)

Transient enhanced diffusion (TED) of boron in silica after low energy boron implantation and annealing was investigated using boron-doping superlattices (DSLs) grown by low temperature molecular beam epitaxy. Boron ions were implanted at 5, 10, 20, and 40 keV at a constant dose of 2{times}10{sup 14}/cm{sup 2}. Subsequent annealing was performed at 750{degree}C for times of 3 min, 15 min, and 2 h in a nitrogen ambient. The broadening of the boron spikes was measured by secondary ion mass spectroscopy and simulated. Boron diffusivity enhancement was quantified as a function of implant energy. Transmission electron microscopy results show that {l_angle}311{r_angle} defects are only seen for implant energies {ge}10 keV at this dose and that the density increases with energy. DSL studies indicate the point defect concentration in the background decays much slower when {l_angle}311{r_angle} defects are present. These results imply there are at least ...

1997-02-01

121

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

International Nuclear Information System (INIS)

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

122

Survey for Transiting Extrasolar Planets in Stellar Systems. II. Spectrophotometry and Metallicities of Open Clusters  

CERN Document Server

We present metallicity estimates for seven open clusters based on spectrophotometric indices from moderate-resolution spectroscopy. Observations of field giants of known metallicity provide a correlation between the spectroscopic indices and the metallicity of open cluster giants. We use \\chi^2 analysis to fit the relation of spectrophotometric indices to metallicity in field giants. The resulting function allows an estimate of the target-cluster giants' metallicities with an error in the method of \\pm0.08 dex. We derive the following metallicities for the seven open clusters: NGC 1245, [m/H]=-0.14\\pm0.04; NGC 2099, [m/H]=+0.05\\pm0.05; NGC 2324, [m/H]=-0.06\\pm0.04; NGC 2539, [m/H]=-0.04\\pm0.03; NGC 2682 (M67), [m/H]=-0.05\\pm0.02; NGC 6705, [m/H]=+0.14\\pm0.08; NGC 6819, [m/H]=-0.07\\pm0.12. These metallicity estimates will be useful in planning future extra-solar planet transit searches since planets may form more readily in metal-rich ...

2005-01-01

123

Structure and magnetic properties of the Al1-xGaxFeO3 family of oxides: A combined experimental and theoretical study  

International Nuclear Information System (INIS)

Magnetic properties of the Al1-xGaxFeO3 family of oxides crystallizing in a non-centrosymmetric space group have been investigated in detail along with structural aspects by employing X-ray and neutron diffraction, Moessbauer spectroscopy and other techniques. The study has revealed the occurrence of several interesting features related to unit cell parameters, site disorder and ionic size. Using first-principles density functional theory based calculations, we have attempted to understand how magnetic ordering and related properties in these oxides depend sensitively on disorder at the cation site. The origin and tendency of cations to disorder and the associated properties are traced to the local structure and ionic sizes. -- Graphical abstract: We have studied both experimentally and theoretically the important role of disorder at the cation site on magnetic and related properties of the Al1-xGaxFeO3 family of oxides crystallizing in a ...

2011-03-01

124

Preparation, characterization and properties of thermochromic tungsten-doped vanadium dioxide by thermal reduction and annealing  

International Nuclear Information System (INIS)

Thermochromic tungsten-doped vanadium dioxide (VO2) powders were successfully synthesized by thermal reduction using V2O5 as a vanadium precursor. The products were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The results indicated that W was successfully doped into the crystal lattice of VO2 matrix, and prepared tungsten-doped VO2 had a rod-like morphology. The effects of reducing temperature and annealing temperature on the crystallographic structures were also discussed. The phase transition temperature (Tt) of VO2 could be simply tuned by changing the doping concentration of tungsten. When the doping concentration was 1.58 mol%, the Tt could be reduced to 37.8 oC from initial 69.5 oC, suggesting that tungsten-doped VO2 possesses prominent thermochromic properties and optical switching characters. It has shown that this convenient and efficient ...

2010-08-20

125

Potassium deposition on a thiophene-terminated alkanethiol monolayer  

International Nuclear Information System (INIS)

Potassium deposition in ultrahigh vacuum on 12-(3-thienyl)dodecanethiol monolayers assembled on gold surfaces has been investigated using X-ray and ultraviolet photoelectron spectroscopies (XPS and UPS). Angle-resolved XPS indicates that initially deposited potassium penetrates the self-assembled monolayer (SAM) and diffuses to the SAM/Au interface. Even after large metal doses, the presence of thiophene ring valence electronic states in the UPS spectra confirms that most of the thiophene rings (at the SAM/vacuum interface) are not covered by potassium. The binding energy shifts of the thiophene ring valence states and the C1s and thiophene S2p peaks, referenced to the Fermi level, are due to the work function changes of the gold substrate. This indicates that these electronic states are pinned to the vacuum level, in contrast to the thiolate S2p orbital, which is pinned to the Fermi level. For large potassium doses, the appearance of new ...

2009-05-01

126

Polypropylene surface modification by active screen plasma nitriding  

International Nuclear Information System (INIS)

Here we describe the use of low energy plasma immersion with active screen as a convenient approach for polypropylene (PP) surface modification. Employing a stainless steel cathodic cage coated with carbon in order to prevent the sputtering of iron from the grid and its deposition onto the polymer sample, the physical chemical properties of PP surface could be effectively modified through the plasma-induced incorporation/formation of nitrogen- and oxygen-containing species. The areal densities of these elements depended on the plasma excitation source, as determined by Rutherford backscattering spectrometry (RBS). Newly formed C-O, C-N, and C=O/O=C-O/N-C=O bonds along with C-C linkages from the PP backbone were identified at the near surface region of the specimens by X-ray photoelectron spectroscopy (XPS). The insertion of such polar reactive functionalities was further confirmed by a substantial decrease in the water contact angle upon plasma ...

2009-03-01

127

Piperidine adsorption on two different silver electrodes: A combined surface enhanced Raman spectroscopy and density functional theory study  

Energy Technology Data Exchange (ETDEWEB)

The surface enhanced Raman scattering (SERS) spectra of piperidine in silver colloid solution, on roughened silver electrode and on roughened silver electrode modified with silver nanoparticles were studied, and the high-quality SERS spectra of piperidine on roughened silver electrode modified with silver nanoparticles were obtained for the first time. Surface selection rules derived from the EM enhancement model were employed to deduce piperidine orientations on the different surfaces. On the basis of this, two models of piperidine adsorbed on the surface of the silver nanoparticles were built, and DFT-B3PW91/LanL2dz was applied to calculate the Raman frequencies. It proves that, at higher potential values, the piperidine is perpendicularly standing on the roughened silver electrode surface though its lone-electron pair, but in silver colloid solution and on the silver nanoparticles modified silver electrode the piperidine molecular lies flat on the silver surface. In the meantime, ...

2007-10-15

128

Lattice relaxation around impurity atoms in semiconductors - arsenic in silicon - a comparison between experiment and theory  

International Nuclear Information System (INIS)

We have measured the lattice relaxation around As in Si at a homogeneous As concentration of 4x10"1"8 cm"-"3 by EXAFS spectroscopy. From the absorption spectra, distances up to the 4th shell could be extracted. A sizeable misfit due to an increased distance is only observed for the 1st shell. Complementing our experimental work we have performed ab initio calculations based on the density functional theory with the WIEN97 package which uses the linearised augmented plane wave method and with the FHI96md program which uses first-principles pseudo-potentials and a plane wave basis set to investigate the size dependence of the super-cells constructed around one substitutional As atom. The calculations yielded good agreement with our EXAFS experiment so that the determined relaxations can be used as a solid basis for further interpretations of derived parameters such as hyperfine interaction parameters in defect complexes.

2003-01-01

129

Interactions of metal cations with anionic groups on the cell Wall of the macroalga vaucheria sp.  

Energy Technology Data Exchange (ETDEWEB)

The aim of this article was to investigate the interactions of metal cations in aqueous solutions with the biomass of the freshwater macroalga Vaucheria sp. This problem is important when elaborating new applications of biosorption, e.g. the production of mineral feed additives for livestock from the biomass of algae enriched with microelement ions. Potentiometric titration was applied as a quick and cheap screening test to search for new efficient biosorbents. It revealed a variety of functional groups capable of cation exchange on the macroalgal surface, including carboxyl, phosphate, hydroxyl or amino groups. Fourier transform infrared spectroscopy on natural and chromium-loaded Vaucheria sp. confirmed that carboxyl groups played a dominant role in the biosorption. The study also showed that Ca(II), Na(I), K(I), and Mg(II) ions were released from the biomass after biosorption of Cu(II), Mn(II), Zn(II), and Co(II) ions, indicating that ion ...

2010-06-15

130

Formation of B_iO_i, B_iC_s, and B_iB_sH_i defects in e-irradiated or ion-implanted silicon containing boron  

International Nuclear Information System (INIS)

The local density functional theory is used to study the electrical levels and thermal stabilities of complexes of interstitial boron with O and C and a boron dimer with H. The energy levels of these defects are compared with those found from deep level transient capacitance spectroscopy experiments on irradiated p-Si containing B. The levels observed at E_c-0.23, E_v+0.29, and E_v+0.51 eV are assigned to B_iO_i, B_iC_s, and B_iB_sH_i respectively. B_iC_s is passivated by one H atom. Evidence for the existence of B_iC_s has implications for mechanisms involved in the suppression of transient-enhanced diffusion of boron in ion-implanted Si by C.

2003-07-28

131

Epitaxial stabilization of MnO(111) overlayers on a Pd(100) surface  

International Nuclear Information System (INIS)

The growth of epitaxial MnO(100) and MnO(111) layers on Pd(100) surface has been investigated by spot-profile analysis low-energy electron diffraction, dynamic atomic force microscopy, photoemission and high-resolution electron energy loss spectroscopy, and density functional theory. We have found that despite the large lattice mismatch to the Pd(100) substrate, the MnO(100) layers are kinetically stabilized at low temperatures (?350 deg. C) and at oxygen pressures between 2x10-7 and 5x10-7 mbar. Annealing in ultrahigh vacuum at 650 deg. C or, alternatively, deposition of manganese metal in oxygen pressure -7 mbar causes the transformation of the MnO(100) to a polar MnO(111) surface, which is decorated by triangular pyramids with (100) side facets. It is suggested that the growth of MnO(111) layers is energetically preferred over MnO(100) due to the epitaxial stabilization at the metal-oxide interface.

2007-06-01

132

Electron momentum spectroscopy of H_2 and D_2: Ionization to ground and excited final states  

International Nuclear Information System (INIS)

The symmetric noncoplanar (e,2e) cross sections (momentum profiles) of H_2 and D_2 for the transitions to the 2p#sigma#_u and 2s#sigma#_g excited ion states have been measured, relative to the ground-state ion transition, using a high-sensitivity multichannel momentum-dispersive electron momentum spectrometer (EMS) at an impact energy of 1200 eV. Newly calculated plane-wave impulse approximation (PWIA) cross sections, based on a full-configuration-interaction H_2 wave function, are compared to the experimental results. These calculations are in better agreement with the experimental results for the transition to the 2s#sigma#_g ion state than the earlier theoretical work of Liu and Smith, Jr. [Phys. Rev. A 31, 3003 (1985)] which has been found to be in error. Nevertheless, significant discrepancies between the relative experimental and theoretical cross sections are observed for the transitions to excited ion states, suggesting a failure of the PWIA description of ...

133

Detection of constitutive heterodimerization of the integrin Mac-1 subunits by fluorescence resonance energy transfer in living cells  

International Nuclear Information System (INIS)

Macrophage differentiation antigen associated with complement three receptor function (Mac-1) belongs to #beta#_2 subfamily of integrins that mediate important cell-cell and cell-extracellular matrix interactions. Biochemical studies have indicated that Mac-1 is a constitutive heterodimer in vitro. Here, we detected the heterodimerization of Mac-1 subunits in living cells by means of two fluorescence resonance energy transfer (FRET) techniques (fluorescence microscopy and fluorescence spectroscopy) and our results demonstrated that there is constitutive heterodimerization of the Mac-1 subunits and this constitutive heterodimerization of the Mac-1 subunits is cell-type independent. Through FRET imaging, we found that heterodimers of Mac-1 mainly localized in plasma membrane, perinuclear, and Golgi area in living cells. Furthermore, through analysis of the estimated physical distances between cyan fluorescent protein (CFP) and yellow fluorescent ...

2006-08-04

134

Crystalline O,O'-di-sec-butyl and O,O'-diethyl dithiophosphate platinum(II) complexes: Synthesis, 13C and 31P CP/MAS NMR, single crystal X-ray diffraction studies and thermal behaviour  

British Library Electronic Table of Contents (United Kingdom)

Crystalline bis(O,O'-di-sec-butyldithiophosphato)platinum(II) was prepared and studied by means of 13C, 31P CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. The unit cell of the platinum(II) compound is comprised of one centrosymmetric mononuclear molecule [Pt{S2P(O-sec-C4H9)2}2], in which the dithiophosphate groups display structural equivalence in both 31P NMR and XRD data. A pair of the dithiophosphate ligands exhibit the same S,S'-bidentate chelating structural function and form two planar four-membered chelate rings, [PtS2P], in this molecule. The planar configuration of the [PtS4] chromophore in structure 1 is governed by the dsp2-hybrid state of platinum(II). The structural states of the dithiophosphate groups in two different samples of complex 1 (one crystallised from...

2011-01-01

135

Comparison of the charge injection barrier at realistic and ideal metal/organic interfaces: metals become faceless  

Energy Technology Data Exchange (ETDEWEB)

Most of the organic electronic devices are nowadays fabricated under poor vacuum conditions. In this regard, there is only little knowledge about the impact of contamination of the metal electrode on the charge injection barrier in this kind of electronic devices. In our study we have performed X-ray and ultra violet photoemission spectroscopy (XPS, UPS) on interfaces between the organic semiconductor -sexithiophene and sputter cleaned (ideal) metals as well as contaminated (realistic) metals. As metal substrates we have used silver, gold, palladium, and platinum. These metals provide us a wide range of metal work functions from 4.2 eV for silver up to 5.5 eV for platinum. For all interfaces of -sexithiophene and contaminated metals we have observed a reduction of the interface dipole and the hole injection barrier. The charge injection barrier in all four cases is almost independent of the underlying metal (within an error of 0.2 eV) and the ...

2007-07-01

136

Chemical synthesis and characterization of Ca-substituted YAlO_3 as electrolyte for solid oxide fuel cells  

International Nuclear Information System (INIS)

In this study, perovskite type oxide YAlO_3 has been doped with different amounts of the divalent cation Ca to synthesize Y_1_-_xCa_xAlO_3_-_#delta# (x = 0-0.21) compositions. The effect of dopant concentration on the crystal structure and electrical properties of YAlO_3 synthesized by citrate gel route has been investigated. The phase purity of the samples has been carried out using X-ray diffraction. The microstructural evaluation of the samples has been conducted by scanning electron microscopy and energy dispersive spectrum analysis. Thermal analysis has been conducted to monitor the decomposition of the intermediate products. The electrical conductivity studies have been performed using a.c. impedance spectroscopy as a function of temperature in the range 200-800 "oC in air. The Y_0_._9_4Ca_0_._0_6AlO_3_-_#delta# composition exhibits a total conductivity of 2.5 mS/cm at 800 "oC.

2010-04-30

137

Apoferritin-Templated Yttrium Phosphate Nanoparticle Conjugates for Radioimmunotherapy of Cancers  

Energy Technology Data Exchange (ETDEWEB)

We report a templated-synthetic approach based on apoferritin to prepare radionuclide nanoparticle (NP) conjugates. Non-radioactive yttrium (89Y) was used as model target and surrogate for radioyttrium (90Y) to prepare the nanoparticle conjugate. The center cavity and multiple channel structure of apoferritin offer a fast and facile method to precipitate yttrium phosphate by diffusing yttrium and phosphate ions into the cavity of apofrritin, resulting a core-shell nanocomposite. The yttrium phosphate/apoferritin nanoparticle was functionalized with biotin for further application. The synthesized nanoparticle was characterized by transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy (XPS). We found that the resulting nanoparticles were uniform in size, with a diameter of around 8 nm. We tested the pre-targeting capability of the biotin-modified yttrium phosphate/apoferritin nanoparticle (yttrium phosphate/apoferritin ...

2008-05-01

138

Advanced organic analysis and analytical methods development: FY 1995 progress report. Waste Tank Organic Safety Program  

Energy Technology Data Exchange (ETDEWEB)

This report describes the work performed during FY 1995 by Pacific Northwest Laboratory in developing and optimizing analysis techniques for identifying organics present in Hanford waste tanks. The main focus was to provide a means for rapidly obtaining the most useful information concerning the organics present in tank waste, with minimal sample handling and with minimal waste generation. One major focus has been to optimize analytical methods for organic speciation. Select methods, such as atmospheric pressure chemical ionization mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry, were developed to increase the speciation capabilities, while minimizing sample handling. A capillary electrophoresis method was developed to improve separation capabilities while minimizing additional waste generation. In addition, considerable emphasis has been placed on developing a rapid screening tool, based on Raman and infrared spectroscopy, for ...

1995-09-01

139

Magnetic excitations studied with time-of-flight spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

An introduction to time-of-flight neutron spectroscopy is presented in the context of the study of magnetic materials. Examples are taken from the class of rare earth and actinide magnetic materials known as `strongly correlated electron` systems. (author) 11 figs., 24 refs.

1996-11-01

140

Low-pressure degenerate four-wave mixing spectroscopy with flam atomization  

Energy Technology Data Exchange (ETDEWEB)

A combination of degenerate four-wave mixing spectroscopy and a low-pressure sampling technique has been studied for isotopic analysis in an air-acetylene flame. Hyperfine spectra of D lines of sodium and several mixtures of lithium isotopes obtained in this way are presented.

1988-08-01

141

Evaluation of the ERETIC Method as an Improved Quantitative Reference for 1H HR-MAS Spectroscopy of Prostate Tissue  

UK PubMed Central (United Kingdom)

The Electronic REference To access In vivo Concentrations (ERETIC) method was applied to 1H HR-MAS spectroscopy. The accuracy, precision, and stability of ERETIC as a quantitative...Full Text Available

2009-03-01

142

Application of spectroscopic techniques for the study of paper documents: A survey  

International Nuclear Information System (INIS)

For many centuries paper was the main material for recording cultural achievements all over the world. Paper is mostly made from cellulose with small amounts of organic and inorganic additives, which allow its identification and characterization and may also contribute to its degradation. Prior to 1850, paper was made entirely from rags, using hemp, flax and cotton fibres. After this period, due to the enormous increase in demand, wood pulp began to be commonly used as raw material, resulting in rapid degradation of paper. Spectroscopic techniques represent one of the most powerful tools to investigate the constituents of paper documents in order to establish its identification and its state of degradation. This review describes the application of selected spectroscopic techniques used for paper characterization and conservation. The spectroscopic techniques that have been used and will be reviewed include: Fourier-Transform Infrared spectroscopy, Raman ...

2009-06-01

143

Application of alpha and gamma spectroscopy to the quantitative analysis of transuranium nuclides in nuclear fuel  

Energy Technology Data Exchange (ETDEWEB)

In nuclear fuel with a burn-up of 33 kg/t U and 52 kg/t U 15 transuranium nuclides /sup 237/Np to /sup 246/Cm have been determined by alpha and gamma spectroscopy after radiochemical separation.

1984-11-01

144

[Determination of sulfite in flue gas desulfurization with seawater by ion chromatography].  

Science.gov (United States)

The technology for flue gas desulfurization (FGD) with seawater is widely adopted by coal-fired power plants in coastal areas. SO2 in the flue gas is absorbed by alkaline seawater and transfered in aqueous phase as sulfite (SO3(2-)), and most SO3(2-) is transformed to sulfate (SO4(2-)) after an aeration process. The remaining SO3(2-) in the seawater discharged to sea area may be harmful to marine organism because of its biological toxicity, thus it is necessary to determine the concentration of SO3(2-) in the seawater for desulfurization. In this study, the method of determination of SO3(2-) in the seawater by ion chromatography was investigated. The separation was achieved on an IonPac AS14A column with 14 mmol/L NaOH-12 mmol/L Na2 CO3 solution as the mobile phase at a flow rate of 1.2 mL/min, and the detection was performed by a pulsed amperometric detector. Formaldehyde was added as a protective agent when sampling because the SO3(2-) is easy to be oxidized. To ...

2009-11-01

145

Studies about oxygen accumulation in palladium silicide formed at Pd/a-Si interface  

International Nuclear Information System (INIS)

... 194 p. auger electron spectroscopy decomposition deposition interfaces oxygen

1986-04-23

146

Nuclear spectroscopy of "1"0"1Mo by sub-Coulomb stripping  

International Nuclear Information System (INIS)

... D.). energy levels molybdenum 101 nuclear properties parity spectroscopic

150

Study of both nature and topology of the nano-porous materials by the positron annihilation spectroscopy  

International Nuclear Information System (INIS)

By the methods of the angular distribution of photon annihilation, time distribution of photon annihilation, photoluminescence spectroscopy, Fourier IR-spectroscopy, atomic force microscopy the detail information on relation of the structural and physical properties of the porous nano-structures is obtained. Study of pores sizes in a different nano-porous materials, such as the porous silicon, porous anode aluminium oxide, porous solids exposed to light atoms ion implantation (hydrogen, deuterium, helium) is carried out.

2003-09-15

151

/sup 18/O isotope effect in carbon-13 nuclear magnetic resonance spectroscopy. Part 8. Oxygen exchange of 2,4,6-trimethylpyrylium cation  

Energy Technology Data Exchange (ETDEWEB)

The rate of the oxygen-exchange reaction in an aqueous solution of a heterocyclic oxygen compound, 2,4,6-trimethylpyrylium perchlorate, was quantitated. The /sup 18/O isotope effect in /sup 13/C NMR spectroscopy affords a direct, continuous, and relatively simple analysis of the reaction and was used to obtain data on the incorporation of /sup 18/O from solvent H/sub 2//sup 18/O into the pyrylium salt. Due to the low solubility of this salt in aqueous solutions, 2,4,6-trimethyl(2-/sup 13/C)pyrylium perchlorate and 2,4,6-trimethyl(2,6-/sup 13/C/sub 2/)pyrylium perchlorate were synthesized to facilitate the acquisition of the data on an NTC-200 spectrometer operating at 50.31 MHz. Upon incorporation of /sup 18/O into the pyrylium salt, the /sup 13/C NMR signal of the directly bonded carbon atom is shifted upfield 0.038 ppm. A /sup 13/C isotope effect is also detected in the doubly /sup 13/C-enriched pyrylium salt where the /sup 13/C NMR signal for /sup 13/C-O-/sup ...

1984-12-12

152

Asymptotic functions and multiplication of distributions  

International Nuclear Information System (INIS)

Considered is a new type of generalized asymptotic functions, which are not functionals on some space of test functions as the Schwartz distributions. The definition of the generalized asymptotic functions is given. It is pointed out that in future the particular asymptotic functions will be used for solving some topics of quantum mechanics and quantum theory.

1976-01-26

153

A numerical study of expected accuracy and precision in Calibration-Free Laser-Induced Breakdown Spectroscopy in the assumption of ideal analytical plasma  

British Library Electronic Table of Contents (United Kingdom)

Calibration-Free Laser-Induced Breakdown Spectroscopy (CF-LIBS) has been proposed several years ago as an approach for quantitative analysis of Laser-Induced Breakdown Spectroscopy spectra. Recently developed refinement of the spectral processing method is described in the present work. Accurate quantitative results have been demonstrated for several metallic alloys. However, the degree of accuracy that can be achieved with Calibration-Free Laser-Induced Breakdown Spectroscopy analysis of generic samples still needs to be thoroughly investigated. The authors have undertaken a systematic study of errors and biasing factors affecting the calculation in the Calibration-Free Laser-Induced Breakdown Spectroscopy spectra processing. These factors may be classified in three main groups: 1) experi...

2007-01-01

157

Multi-functional Biocompatible Coatings  

International Science & Technology Center (ISTC)

Multi-functional Bioactive Nano-structured Coatings for Load-Bearing Implants

158

The Structure of the Amyloid-[beta] Peptide High-Affinity Copper II Binding Site in Alzheimer Disease  

Energy Technology Data Exchange (ETDEWEB)

Neurodegeneration observed in Alzheimer disease (AD) is believed to be related to the toxicity from reactive oxygen species (ROS) produced in the brain by the amyloid-{beta} (A{beta}) protein bound primarily to copper ions. The evidence for an oxidative stress role of A{beta}-Cu redox chemistry is still incomplete. Details of the copper binding site in A{beta} may be critical to the etiology of AD. Here we present the structure determined by combining x-ray absorption spectroscopy (XAS) and density functional theory analysis of A{beta} peptides complexed with Cu{sup 2+} in solution under a range of buffer conditions. Phosphate-buffered saline buffer salt (NaCl) concentration does not affect the high-affinity copper binding mode but alters the second coordination sphere. The XAS spectra for truncated and full-length A{beta}-Cu{sup 2+} peptides are similar. The novel distorted six-coordinated (3N3O) geometry around copper in the A{beta}-Cu{sup ...

2008-11-03

159

Study of the outgassing behavior of SnO_2:F films on glass in vacuum under external energy excitation  

International Nuclear Information System (INIS)

Vacuum glazing consists of an evacuated space between two sheets of glass. Vacuum glazing has a large effect on energy savings in houses and buildings. Vacuum glazing can achieve higher insulating performance than conventional insulated glazing. Nippon Sheet Glass has successfully developed conventional vacuum glazing. In this study we investigated an advanced form of vacuum glazing. Its thermal insulation ability is equivalent to 100 mm thick glass wool thermal insulation. This vacuum glazing contained a SnO_2:F low emissivity surface. The influence of the residual gas in a vacuum space on heat flow is important to performance. For long-term thermal stability, it is very important to maintain vacuum stability. To understand this better, we studied the behavior of outgassing from the inside glass surfaces exposed to an external energy source. We have studied the behavior of outgassing from a glass surface using a Nd:YAG laser (operated at 355 nm wavelength) and Q-mass ...

2005-06-15

160

Study of the electron beam irradiation effect on some properties of aromatic aliphatic copolyester films; Estudo do efeito da radiacao por feixe de eletrons nas propriedades de filmes de copoliester alifatico aromatico  

Energy Technology Data Exchange (ETDEWEB)

Biodegradable and green plastics are the new tendency in the world. The effect of the electron beam irradiation in aromatic aliphatic copolyester and the blend with corn starch films (Ecoflex{sup R} and Ecobras{sup R}) were studied by tensile strength at break, elongation at break, Scanning Electronic Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), crosslinking degree and biodegradability. The measurements in both, the machine direction and the transverse direction were made for mechanical tests. It was found that, the electron irradiation caused an increase in the strength at break of the blend with corn starch film, when doses of up to 10 kGy were applied. A significant decrease of the elongation at break of the blend with corn starch was observed at doses of 10 kGy and 40 kGy. It was not found important change in tensile properties for aromatic aliphatic copolyester. Structural changes of the samples ...

2008-07-01

161

Study of the electron beam irradiation effect on some properties of aromatic aliphatic copolyester films  

International Nuclear Information System (INIS)

Biodegradable and green plastics are the new tendency in the world. The effect of the electron beam irradiation in aromatic aliphatic copolyester and the blend with corn starch films (Ecoflex"R and Ecobras"R) were studied by tensile strength at break, elongation at break, Scanning Electronic Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimetry (DSC), crosslinking degree and biodegradability. The measurements in both, the machine direction and the transverse direction were made for mechanical tests. It was found that, the electron irradiation caused an increase in the strength at break of the blend with corn starch film, when doses of up to 10 kGy were applied. A significant decrease of the elongation at break of the blend with corn starch was observed at doses of 10 kGy and 40 kGy. It was not found important change in tensile properties for aromatic aliphatic copolyester. Structural changes of the samples ...

162

Structural and electrical characteristics of epitaxial CoSi{sub 2} grown on n-Si{sub 0.83}Ge{sub 0.17}/n-Si(001) by reactive chemical vapor deposition using a Si capping layer  

Energy Technology Data Exchange (ETDEWEB)

Epitaxial cobalt disilicide (CoSi{sub 2}) layers are grown on n-Si{sub 0.83}Ge{sub 0.17}/n-Si(001) using a sacrificial Si capping layer at the growth temperature T{sub s}=650 deg. C by reactive chemical vapor deposition using cyclopentadienyl dicarbonyl cobalt (Co({eta}{sup 5}-C{sub 5}H{sub 5})(CO){sub 2}). Structural and electrical properties of epi-CoSi{sub 2}/Si{sub 0.83}Ge{sub 0.17}/Si(001) were measured by transmission electron microscopy, X-ray diffraction, Auger electron spectroscopy and sheet resistance measurement as a function of annealing temperature. The combined results showed that the epitaxial CoSi{sub 2} phase by the reaction of Co with the Si capping layer was formed in the as-grown layers. Rapid thermal anneals for the investigation of thermal stability of the as-grown layers showed good thermal stability of the epitaxial CoSi{sub 2} layers with the low sheet resistance value as low as congruent with 4.4 {omega}/cm up to the ...

2004-06-30

163

Structural and electrical characteristics of epitaxial CoSi_2 grown on n-Si_0_._8_3Ge_0_._1_7/n-Si(001) by reactive chemical vapor deposition using a Si capping layer  

International Nuclear Information System (INIS)

Epitaxial cobalt disilicide (CoSi_2) layers are grown on n-Si_0_._8_3Ge_0_._1_7/n-Si(001) using a sacrificial Si capping layer at the growth temperature T_s=650 deg. C by reactive chemical vapor deposition using cyclopentadienyl dicarbonyl cobalt (Co(#eta#"5-C_5H_5)(CO)_2). Structural and electrical properties of epi-CoSi_2/Si_0_._8_3Ge_0_._1_7/Si(001) were measured by transmission electron microscopy, X-ray diffraction, Auger electron spectroscopy and sheet resistance measurement as a function of annealing temperature. The combined results showed that the epitaxial CoSi_2 phase by the reaction of Co with the Si capping layer was formed in the as-grown layers. Rapid thermal anneals for the investigation of thermal stability of the as-grown layers showed good thermal stability of the epitaxial CoSi_2 layers with the low sheet resistance value as low as congruent with 4.4 #OMEGA#/cm up to the annealing temperature as high as 850 deg. C without ...

2004-06-30

164

Simulation of dopant diffusion and activation during flash lamp annealing  

International Nuclear Information System (INIS)

A set of advanced models implemented into the simulator Sentaurus Process was applied to simulate ultra shallow junction formation by flash lamp annealing (FLA). The full path transient enhanced diffusion model includes equations for small interstitial clusters (I_2, I_3, I_4), #left brace#3 1 1#right brace# defects and dislocation loops. A dopant-point defect clustering model is used for dopant activation simulation. Several cluster types are considered: B_2, B_2I, B_2I_2, B_3I, B_3I_2, B_3I_3 for boron and As_2, As_2V, As_3, As_3V, As_4, As_4V for arsenic. Different point defect and dopant-point defect pair charge states are taken into account to obtain accurate results in the high doping level region. The flux expressions in the three-phase segregation model include a dependence on the doping level and point defect supersaturation. The FLA process was performed at various peak temperatures in a Mattson Millios"T"M fRTP"T"M system. The measured wafer temperature as a ...

2008-12-05

165

Schottky barrier and homojunction gallium arsenide solar cells  

Energy Technology Data Exchange (ETDEWEB)

New techniques were developed to construct Schottky barrier and homojunction solar cells on GaAs substrates. Schottky barrier metal-semiconductor solar cells were produced for the first time on p-type GaAs substrate using a sputter-deposition method to form the barrier. The sputter deposition of gold or gold/palladium is the key to the method since normal thermal evaporation of gold onto p-type GaAs produces ohmic contacts. The results of this investigation are consistent with the idea that sputter damage produces donor type surface states on GaAs. Barrier heights were measured for both p-type sputtered and n-type thermally evaporated diodes using current-voltage and capacitance-voltage methods. Deep-level transient spectroscopy was used to identify the trap center concentration and energy levels for both diodes in an effort to explain the relatively large dark current in the p-type sputtered diodes. Homojunction GaAs solar cells were fabricated using several ...

1983-01-01

166

Properties of dust particles sampled from windboxes of an iron ore sintering plant: Surface structures of unburned carbon  

Energy Technology Data Exchange (ETDEWEB)

Aiming to understand the formation mechanism of dioxins in the iron ore sintering process, dust samples obtained from some windboxes of a commercial iron ore sintering plant have been characterized with a powder X-ray diffraction (XRD), by the transmission electron microscope (TEM) equipped with an electron energy loss spectroscopy (EELS), and by the temperature-programmed desorption (TPD) and temperature-programmed oxidation (TPO) techniques. The elemental and XRD analyses reveal that the content of the Cl present in the samples ranges from 0.075 mass%-dry to 5.1 mass%-dry and tends to be higher at smaller dust particles, and that some of the Cl exists as KCl with the average crystalline size between 40 nm and 50 nm. Dust samples also contain a significant amount of unburned carbon, and the smallest dust particles, < 500 {mu}m, show the highest C contents in many cases and consist partly of C, K, and Cl elements. The TPD and TPO experiments exhibit that the ...

2006-07-01

167

Plasma treatment of the Mg:Ag/tris-(8-hydroxyquinoline) aluminum interface in OLEDs: effects on adhesion and performance  

Energy Technology Data Exchange (ETDEWEB)

The adhesion of a Mg:Ag cathode to the tris-(8-hydroxyquinoline) aluminum (Alq{sub 3}) in organic light emitting devices (OLEDs) can be greatly enhanced by a remote plasma treatment of the Alq{sub 3} layer using either air or N{sub 2} prior to metal deposition. The altered surface properties which lead to increased sticking coefficients of Mg and Ag, as well as enhanced adhesion, are attributed to the introduction of new functional groups into the organic layer, as observed by X-ray photoelectron spectroscopy (XPS). The storage life of the plasma treated devices in air without any capping treatment, as judged by a visible deterioration of the cathode, was increased by approximately five to six times compared to untreated OLEDs. Current-voltage characteristics and EL efficiency, however, were shown to deteriorate for devices incorporating either an air or an N{sub 2} plasma treated Alq{sub 3} layer. For OLEDs subjected to short treatment times ...

2004-05-31

168

Origins of residual stress in Mo and Ta films: The role of impurities, microstructural evolution, and phase transformations  

Energy Technology Data Exchange (ETDEWEB)

Both the sign and magnitude of residual stress can vary with the thickness of sputter deposited films. The origins of this behavior are not well understood. In this work, the authors consider the correlation between the residual stress behavior and the depth dependence of impurities in thin (2.5 nm--150 nm) sputtered Mo and Ta films. They also consider the effects of phase transformations and microstructural changes on the stress behavior. Films were deposited onto Si substrates with native oxide. The residual stress observed in the Mo films varied from highly compressive at 2.5 nm film thickness to {approximately}0 at 10 nm thickness. Ta films also exhibited a high compressive stress, which relaxed from highly compressive to tensile between 10 nm and 50 nm film thickness. Impurities in the films may originate from the sputtering targets, the background gases, and the substrate surfaces. Auger Electron Spectroscopy (AES) results showed the presence of O and C ...

1997-05-01

169

Making porous membranes by chemical etching of heavy-ion tracks in {beta}-PVDF films  

Energy Technology Data Exchange (ETDEWEB)

Production of porous membranes using heavy ion bombardment and subsequent chemical etching of poly(vinylidene difluoride) (PVDF) films has been reported several years ago. However, porous membranes with pore diameter in the nanometer scale requires a better understanding of the chemical etching mechanism. In this work PVDF foils irradiated with Sn ions (2.85 MeV per nucleon) were exposed to several etching conditions which involved permanganate oxidation in different alkaline environments. The solution of KOH 9 mol L{sup -1} and saturated in KMnO{sub 4} was the best etching reactant for PVDF. Functional groups created in the alkaline and oxidative attack by permanganate were studied by FT-IR and UV-vis spectroscopy. The spectroscopic data reveals that the formation of pores occurs by a two-step mechanism: (i) double bonds as a result of dehydrofluorination induced by alkaline media and (ii) oxidation of these double bonds in permanganate ...

2005-07-01

170

Kinetic and mechanistic studies of the reactions of CF{sub 3}O radicals with NO and NO{sub 2}  

Energy Technology Data Exchange (ETDEWEB)

The reactions of CF{sub 3}O radicals with (1) NO and (2) NO{sub 2} were studied using two different experimental techniques. A laser photolysis/LIF detection method was applied for measuring the rate constants as a function of temperature (T=222-302 K) and total pressure (p{sub tot}=7-107 mbar). Whereas the reaction with (1) NO was found to be independent of temperature and pressure with k{sub 1}=(4.5{+-}1.2) x 10{sup -11} cm{sup 3}s{sup -1}, the reaction with (2) NO{sub 2} was found to be dependent on both of these variables. The temperature dependence of k{sub 2} in the high pressure limit can be given by the expression k{sub 2{infinity}}{sup -}(T)=(8{+-}5) x 10{sup -13} exp ((863{+-}194) K/T) cm{sup 3}s{sup -1}. The product distributions of the two reactions were determined in separate experiments using steady-state photolysis combined with FTIR spectroscopy. For reaction (1) only CF{sub 2}O was found as a reaction product with a yield of ...

1997-10-01

171

In-situ FT-IR spectroscopic studies of coal drying. In-situ FT-IR ho wo mochiita sekitan no kanso ni kansuru kenkyu  

Energy Technology Data Exchange (ETDEWEB)

This paper discusses spectral change in brown coal and bituminous coal as a result of low-temperature drying. The experiment used a Fourier transform infrared (FT-IR) spectroscopy disposed with an in-situ diffuse reflector as a water content measuring method. The FT-IR spectra of coal showed the existence of two types of adsorbed water. One of the two spectral peaks was thought to have been caused by isolated water molecules which may have been hydrogen bonded to hydrocarbon in the coal molecules and weakly bound. The other peak was thought to have been caused by water which may have been hydrogen bonded to functional groups such as hydroxyl groups in the coal molecules and strongly bound. Drying behavior in brown coal and bituminous coal showed the absorption peak at 3640 cm[sup -1] reducing faster than the absorption peak at 3360cm[sup -1]. Depressurized drying was found to be more effective than flowing nitrogen gas. The extent of absorption ...

1993-01-29

172

Growth and characterization of new semi-organic L-proline strontium chloride monohydrate single crystals  

International Nuclear Information System (INIS)

The present communication deals with the synthesis, single crystal growth and characterization of a new nonlinear optical material L-proline strontium chloride monohydrate (L-PSCM). Single crystals have been grown using the slow solvent evaporation technique. Single crystal XRD analysis confirmed that the crystal belongs to the orthorhombic structure with lattice parameter a=6.6966(3) A, b=12.4530(5) A, c=15.2432(5) A and space group P2_12_12_1. Presence of various functional groups in L-PSCM and protonation of the ions were confirmed by Fourier transform infrared spectroscopy (FT-IR) analysis. The melting point of the single crystal was found to be 126 "oC using DSC. Ultraviolet-visible spectral analyses showed that the crystal has low UV cut-off at 226 nm combined with very good transparency of 90% in a wide range. The optical band gap was estimated to be 5.82 eV. Capacitance and dielectric-loss measurements were carried out at different ...

2011-01-01

173

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

Energy Technology Data Exchange (ETDEWEB)

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

2005-06-01

174

Effects of ion-induced electron emission on magnetron plasma instabilities  

International Nuclear Information System (INIS)

Some magnetron sputtering systems experience rapid oscillations in the current and voltage of the plasma discharge after several hours when equipped with certain targets. These oscillations often lead to the plasma becoming extinguished, a condition known as ''flame-out.'' This article details the study of two 90% W--10% Ti magnetron targets which differed in density. The higher density targets sometimes experienced flame-out after approximately 3 h of sputtering. The less dense material could be sputtered for the entire 15 h life of the target. Scanning electron microscopy pictures and atomic composition depth profiles were obtained using Auger electron spectroscopy. In addition, a Colutron-based ion source with a high vacuum system was used to measure ion-induced secondary electron emission coefficients as a function of energy, ion specie, and gas coverage. Analysis of the sample from the group that suffers flame-out showed large regions of ...

175

Thulium-doped vanadate crystals: Growth, spectroscopy and laser performance  

British Library Electronic Table of Contents (United Kingdom)

This work is concentrated on growth, spectroscopy and laser performance of thulium-doped vanadate crystals. At the beginning the growth techniques are analyzed and then the matrix of vanadates crystal, its structure and physicochemical properties are explained together with the rare earth activators influence. Detailed spectroscopy of the thulium-doped vanadate crystals then follows. On the background of this theoretical analysis and state of the art of the subject the description of thulium vanadate lasers (especially Tm:YVO"4, Tm:GdVO"4, and Tm:LuVO"4) together with their generated output radiation characteristics are presented.

2011-01-01

176

In-beam spectroscopy of nuclei  

International Nuclear Information System (INIS)

The main features and advantages of a new low energy nuclear spectroscopic method, the in-beam spectroscopy are described. Results of in-beam spectroscopic experiments performed at the Institute of Nuclear Research (ATOMKI, Debrecen, Hungary) are summarized. Gamma spectra of in-beam produced odd-odd nuclei were measured, gamma-energies were determined. Measurement of gamma-gamma coincidences led to the construction of energy level schemes of the investigated nuclei. Internal conversion electron spectroscopy was used to determine the multipolarities of transitions. A few spectra and level schemes are presented to illustrate the review. Theoretical interpretation of experimental results are briefly summarized. (D.Gy.).

1982-01-01

177

In-beam #gamma#-ray spectroscopy of fast beams at the NSCL  

International Nuclear Information System (INIS)

With the development of an array of highly-segmented germanium detectors, it now becomes possible to perform in-flight #gamma#-ray spectroscopy experiments on intermediate energy beams with unprecedented #gamma#-ray energy resolution. Presented in this report are examples of two techniques in which SeGA, the most highly-segmented operational germanium array for in-flight spectroscopy with fast beams, was used for the detection of #gamma# rays. SeGA used in conjunction with a high-resolution magnetic spectrograph (S800) to detect the reaction residues in coincidence represents a powerful combination for in-beam #gamma#-ray studies.

2004-04-05

178

Applications of infrared and Raman spectroscopy in industry  

Energy Technology Data Exchange (ETDEWEB)

There have been many recent explosive advances in both IR and Raman spectroscopy which have developed in response to industrial problems of increasing complexity. Probably the biggest factor in these advances has been computerization, which has contributed not only to substantial improvements in data handling but to enormous gains in sensitivities of analyses as well. In this paper numerous examples of Raman and IR applications in industry are given using many of these recent advances, including in-situ techniques, microprobe analyses, unusual combinations of instruments - i.e., hyphenated methods - and new sample handling techniques. The bright future of FT-IR and Raman spectroscopy is also briefly discussed.

1986-07-01

179

Spatially resolved IR absorption spectroscopy by optical Stark modulation  

Energy Technology Data Exchange (ETDEWEB)

The first application of optical Stark modulation has been applied to measure spatially precise Stark-modulated IR absorption spectra in a flame.

1982-12-01

180

Quantitative Spectroscopy of Photospheric-Phase Type II SN  

Science.gov (United States)

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

181

New and old Sn isomers produced in heavy-ion collisions  

International Nuclear Information System (INIS)

The energy level schemes of tin isotopes produced in the heavy ion reactions are presented. The using of #gamma# spectroscopy technique is also described. 4 refs, 12 figs.

1991-12-01

182

Neutron time-of-flight spectroscopy and the reaction "8"8Sr("3He,n)"9"0Zr  

International Nuclear Information System (INIS)

... states helium 3 reactions ion sources mev range 10-100 neutron spectrometers

183
184

Localized H-1 MR spectroscopy in postnatal brain development  

International Nuclear Information System (INIS)

This paper investigates regional and age-related changes in metabolite ratios using image-localized H-1 MR spectroscopy in children. Twenty-seven children referred for MR imaging of the brain underwent localized H-1 MR spectroscopy with a Siemens 1.5-T whole-body imager. Localization to 2 x 2 x 2-cm volumes of interest was achieved with a stimulated-echo or spin-echo technique. Repetition times of 1,600 and 5,000 msec were used, with echo times varying between 68 and 270 msec. Total combined imaging and spectroscopy times were 90-120 minutes.

1990-11-25

185

Gamma-spectroscopy of "6"4Mn_3_9 and "6"6Mn_4_1 decays  

International Nuclear Information System (INIS)

... v. 33(4). beta-minus decay de-excitation delayed gamma radiation iron 64

188

Asymptotic numbers, asymptotic functions and distributions  

International Nuclear Information System (INIS)

The asymptotic functions are a new type of generalized functions. But they are not functionals on some space of test-functions as the distributions of Schwartz. They are mappings of the set denoted by A into A, where A is the set of the asymptotic numbers introduced by Christov. On its part A is a totally-ordered set of generalized numbers including the system of real numbers R as well as infinitesimals and infinitely large numbers. Every two asymptotic functions can be multiplied. On the other hand, the distributions have realizations as asymptotic functions in a certain sense. (author).

2007-05-18

189

UV photoelectron yield spectroscopy of chalcopyrite structure Cu-In-Se thin films  

International Nuclear Information System (INIS)

Surface-sensitive UV photoelectron yield spectroscopy was employed to study electron acceptor levels at surfaces of chalcopyrite structure Cu-In-Se thin films. Surface Fermi level pinning was observed for Cu-rich films. Shallow acceptor levels ascribable to defects Cu_I_n and V_C_u were observed for near-stoichiometric and In-rich films respectively. (orig.).

190

Quantitative 31P NMR Spectroscopy and 1H MRI Measurements of Bone Mineral and Matrix Density Differentiate Metabolic Bone Diseases in Rat Models  

UK PubMed Central (United Kingdom)

In this study, bone mineral density (BMD) of normal (CON), ovariectomized (OVX) and partially nephrectomized (NFR) rats was measured by 31P NMR spectroscopy; bone matrix density was...Full Text Available

2010-06-01

191

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

International Nuclear Information System (INIS)

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

192

Nitrogen isotope identification by Bragg-curve spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

Projectilelike fragments following the 80 MeV /sup 16/O+/sup 27/Al reaction have been detected using a Bragg-curve spectroscopy ionization chamber (BCS-IC). The atomic number is deduced from the Bragg-peak amplitude. Nitrogen isotopes are clearly resolved using either range or energy loss data. This is the first application of the BCS method for complete ion identification in a heavy-ion-induced reaction.

1984-07-14

193

Nitrogen isotope identification by Bragg-curve spectroscopy  

International Nuclear Information System (INIS)

Projectilelike fragments following the 80 MeV "1"6O+"2"7Al reaction have been detected using a Bragg-curve spectroscopy ionization chamber (BCS-IC). The atomic number is deduced from the Bragg-peak amplitude. Nitrogen isotopes are clearly resolved using either range or energy loss data. This is the first application of the BCS method for complete ion identification in a heavy-ion-induced reaction.

194

Levels in "7"2Se observed via in-beam gamma-ray spectroscopy in the "5"8Ni("1"6O,2p) reaction  

International Nuclear Information System (INIS)

Levels in "7"2Se were observed via in-beam gamma spectroscopy following the "5"8Ni("1"6O,2p) reaction. Spectra and partial energy level schemes are shown. (3 figures) (U.S.).

1975-05-01

195

Evaluation of two-beam spectroscopy as a plasma diagnostic  

Energy Technology Data Exchange (ETDEWEB)

A two-beam spectroscopy (TBS) system is evaluated theoretically and experimentally. This new spectroscopic technique uses correlations between components of emitted light separated by a small difference in angle of propagation. It is thus a non-perturbing plasma diagnostic which is shown to provide local (as opposed to line-of-sight averaged) information about fluctuations in the density of light sources within a plasma - information not obtainable by the usual spectroscopic methods. The present design is an improvement on earlier systems proposed in a thesis by Rostler.

1980-04-01

196

Determination of the isomeric composition and structure of bicyclo(3. 3. 1)nonadienes by PMR spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The isomeric composition of bicyclo(3.3.1)nonadienes was investigated by GLC and PMR spectroscopy with silver-lanthanide shift reagents. The absence of stereospecificity in the hydrogenation of 3,7-dimethylenebicyclo(3.3.1)nonane by hydrogen adsorbed on Raney nickel was demonstrated. This is explained by the sequence of the isomerization and then hydrogenation processes.

1986-01-10

197

Comparative study on tea chemical analysis; Estudo comparativo na analise quimica de chas  

Energy Technology Data Exchange (ETDEWEB)

This paper describes the application of the instrumental analytical methods: neutron activation techniques, atomic absorption spectroscopy and flame emission spectroscopy, used to analyse some home-made teas, determining Na, K and Cl and comparing the results. This study verify whether the home-made teas used for rehydration of the children reach the composition recommended by WHO (World Health Organization). (author). 6 refs., 6 tabs.

1995-12-31

198

Bragg curve spectroscopy in a 4? geometry  

Science.gov (United States)

Ionization counters employing Bragg curve spectroscopy have been constructed for use in a 4? geometry. These detectors compare very favorably in terms of both energy and charge resolution with small solid angle devices. These detectors have a large dynamic range because they are backed by scintillation detectors, and are thus capable of detecting and identifying particles with energies from 1 MeV/nucleon up to 200 MeV/nucleon.

1991-02-01

199

Bragg curve spectroscopy in a 4. pi. geometry  

Energy Technology Data Exchange (ETDEWEB)

Ionization counters employing Bragg curve spectroscopy have been constructed for use in a 4{pi} geometry. These detectors compare very favorably in terms of both energy and charge resolution with small solid angle devices. These detectors have a large dynamic range because they are backed by scintillation detectors, and are thus capable of detecting and identifying particles with energies from 1 MeV/nucleon up to 200 MeV/nucleon. (orig.).

1991-02-01

200

Bragg curve spectroscopy in a 4#pi# geometry  

International Nuclear Information System (INIS)

Ionization counters employing Bragg curve spectroscopy have been constructed for use in a 4#pi# geometry. These detectors compare very favorably in terms of both energy and charge resolution with small solid angle devices. These detectors have a large dynamic range because they are backed by scintillation detectors, and are thus capable of detecting and identifying particles with energies from 1 MeV/nucleon up to 200 MeV/nucleon. (orig.).

201

Bragg curve spectroscopy detector for particle identification  

International Nuclear Information System (INIS)

The operation principle, construction and characteristics of the Bragg curve spectroscopy detector (BCS detector) are described. The electric field of the BCS detector is parallel to the particle trajectories. The detector was tested by 8.78 MeV and 6.02 MeV #alpha# particles from a ThC-ThC's source. The energy resolutions are 1.5% and 2.6% respectively for two groups of #alpha# particles, and the charge resolution is 2.7%. Further test experiments with heavy ions will be arranged.

202

Bragg curve spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

A new method named 'Bragg curve spectroscopy', based on the Bragg curve of the heavy ion being stopped in a gaseous ionization chamber, has been developed for identifying the particle and measuring its energy. The design of such a chamber and the experience obtained with chamber using various kinds of fast heavy ions are described. In conclusion, several problems to be solved in this method are pointed out.

1982-05-01

203

Bragg curve spectroscopy  

International Nuclear Information System (INIS)

A new method named 'Bragg curve spectroscopy', based on the Bragg curve of the heavy ion being stopped in a gaseous ionization chamber, has been developed for identifying the particle and measuring its energy. The design of such a chamber and the experience obtained with chamber using various kinds of fast heavy ions are described. In conclusion, several problems to be solved in this method are pointed out. (orig.).

204

Application of alpha and gamma spectroscopy to the quantitative analysis of transuranium nuclides in nuclear fuel  

International Nuclear Information System (INIS)

In nuclear fuel with a burn-up of 33 kg/t U and 52 kg/t U 15 transuranium nuclides "2"3"7Np to "2"4"6Cm have been determined by alpha and gamma spectroscopy after radiochemical separation. (author).

218

Wave function of an anisotropic universe  

Energy Technology Data Exchange (ETDEWEB)

The wave function of the Bianchi type-IX universe with small anisotropy is calculated using the Hartle-Hawking prescription.

1985-06-15

219

Wave function of an anisotropic universe  

International Nuclear Information System (INIS)

The wave function of the Bianchi type-IX universe with small anisotropy is calculated using the Hartle-Hawking prescription.

220

Overview on some functional issues related to the uninterrupible power systems design  

CERN Document Server

Overview on some functional issues related to the uninterrupible power systems design

1989-01-01

221

On Lg-Splines.  

Science.gov (United States)

Spline functions associated with a general linear differential operator L which interpolate prescribed data with respect to arbitrary linear functionals are investigated. (Author)

1968-01-01

222

Complexity of the microstructure evolution for optimization cBN growth in a four-step ion-assisted deposition process  

International Nuclear Information System (INIS)

The changes in microstructure of a specially prepared boron nitride (BN) film as a function of film depth were studied by high resolution transmission electron microscopy (HRTEM) and other materials analysis tools. These changes were then correlated to the changes in processing parameters during film growth. The analyzed film was fabricated by the four-step ion-assisted deposition procedure known to be effective in film-stress engineering for the formation and retention of a thick cubic BN (cBN) layer with a three-step buffer-layer deposition. In this deposition, the energy of the ions assisting cBN formation was increased stepwise from 200 to 280, and then to 360 eV [S.F. Wong, C. W. Ong, G.K.H. Pang, K.Z. Baba-Kishi, W. M. Lau, J. Vac. Sci. Technol. A 22 (2004) 676]. The nominal thickness of the cBN layer was 650 nm and that for each of the three buffer layers was about 160 nm. Both the HRTEM and electron diffraction results confirmed that the top cBN layer, with ...

2005-10-01

223

Time-resolved triple-axis spectroscopy - a new method for real-time neutron scattering  

International Nuclear Information System (INIS)

A new method for kinetic experiments with neutrons is described. This method combines the conventional triple-axis neutron spectroscopy with relaxation-type experiments. Whereas the former method yields information about the microscopic dynamics of solids, the latter provides macroscopic relaxation times. The combination of both methods allows to determine the microscopic mechanism of relaxation processes. The time-resolved triple-axis spectroscopy is limited to reversible processes and to time scales from 10"-"3 to 10"4 s. Typical applications are the kinetics of phase transformations (structural and dynamical changes), kinetics of domain distributions, kinetics of (spinodal) decomposition, reversible solid state reactions, time-dependent occupation of phonon states or phonon lifetimes. (orig.).

1990-04-01

224

Spatial fluorescence cross correlation spectroscopy by means of a spatial light modulator  

CERN Document Server

Spatial Fluorescence Cross Correlation Spectroscopy is a rarely investigated version of Fluorescence Correlation Spectroscopy, in which the fluorescence signals from differ-ent observation volumes are cross-correlated. In the reported experiments, two observation volumes, typically shifted by a few $\\mu$m, are produced, with a Spatial Light Modulator and two adjustable pinholes. We illustrated the feasibility and potentiality of this technique by: i) measuring molecular flows, in the range 0.2 - 1.5 $\\mu$m/ms, of solutions seeded with fluorescent nanobeads or rhodamine molecules (simulating active transport phenomenons); ii) investigating the perme-ability of phospholipidic membrane of Giant Unilamellar Vesicles versus hydrophilic or hydrophobic molecules (in that case the laser spots were set on both sides of the mem-brane). Theoretical descriptions are proposed together with a discussion about FCS based, alternative methods.

2008-01-01

225

Point-contact Andreev spectroscopy on thin Ni_2MnIn Heusler films  

International Nuclear Information System (INIS)

Heusler films with L2_1 and B2 structure are deposited simultaneously on amorphous carbon films, Si(100) surfaces, and in situ cleaved InAs(110) surfaces by coevaporation of Ni and the alloy MnIn. Morphology, structure, and stoichiometry are investigated with transmission-electron microscopy, electron diffraction, and X-ray spectroscopy. The almost perfect lattice match supports highly oriented growth of Ni_2MnIn on InAs, which is proven by electron diffraction under grazing incidence. The electrical resistivity of thin films on Si show metallic behavior. At temperatures of liquid helium point-contact Andreev reflection spectroscopy is performed on films grown on Si(100) and in situ cleaved InAs(110) surfaces yielding spin polarizations comparable to the ones of Fe, Ni, Co, and permalloy (Ni_8_0Fe_2_0).

2007-09-01

226

Photo-emission-electron-microscopy for characterization of an operating organic electronic device  

Energy Technology Data Exchange (ETDEWEB)

Photoemission-electron-microscopy (PEEM) is introduced as a tool for the characterization of organic electronic devices. PEEM-measurements are used for imaging as well as for spectroscopic analyses by illumination with light of a Hg-lamp (4.9 eV), a D2 lamp (7.3 eV), and with synchrotron radiation for resonant photoelectron spectroscopy. We determine the charge carrier concentration inside the channel region of the organic device and its lateral distribution. From resonant photoelectron spectroscopy (RPES) we deduce the electronic states which are accessible with the Hg and D2 illumination. Photoelectron-spectroscopy at selected areas ({mu}-PES) gives information on the absolute values of surface potentials in lateral resolution. We are able to perform these studies with applied voltages at the source- and drain-electrode.

2006-01-20

227

Monitoring amino acids, organic acids, and ripening changes in Cheddar cheese using Fourier-transform infrared spectroscopy  

British Library Electronic Table of Contents (United Kingdom)

Fourier-transform infrared (FTIR) spectroscopy was used to monitor amino acids, organic acids, and changes during ripening. Twelve Cheddar cheese samples were ripened for 73 days and samples were drawn periodically. Water-soluble fractions of samples were analyzed by gas chromatography (20 amino acids), liquid chromatography (three organic acids), and FTIR spectroscopy (4000-700 cm-1). Spectra were correlated with chromatographic data and ripening events and analyzed by multivariate statistics to develop prediction and classification models. Most models showed a good fit (correlation coefficient > or =0.89) and could predict the levels of amino acids and organic acids and age of the cheese in less than 20 min. Lactic acid, leucine, glutamic acid, asparagine, phenylalanine, and valine were ...

2011-01-01

228

LDEF impact craters formed by carbon-rich impactors  

International Nuclear Information System (INIS)

Two small craters (number 74, 119 microns, and number 31, 158 microns in diameter) with depth to diameter ratios of about 0.59 and 0.8, respectively, were found in Al from the Long Duration Exposure Facility (LDEF) experiment tray A11EOOF. Both craters have residues concentrated in the crater bottoms, along the walls, and on top of the overturned rims. Low voltage scanning electron electron microscopy, Auger electron spectroscopy, time of flight secondary ion mass spectroscopy and energy dispersive x-ray spectroscopy were used to obtain high resolution imagery and elemental analysis. Analyses indicate that the impactor for both craters was carbon-rich, as the residues contain mostly C. Silicon, S, and F in low concentrations are present on the Al surface away from the craters and may be, in part, contaminants.

1991-06-01

229

Imazalil-cyclomaltoheptaose (beta-cyclodextrin) inclusion complex: preparation by supercritical carbon dioxide and 13C CPMAS and 1H NMR characterization.  

Science.gov (United States)

An inclusion complex between imazalil (IMZ), a selected fungicide, and cyclomaltoheptaose (beta-cyclodextrin, betaCD) was obtained using supercritical fluid carbon dioxide. The best preparation conditions were determined, and the inclusion complex was investigated by means of 1H NMR spectroscopy in aqueous solution and 13C CPMAS NMR spectroscopy in the solid state. Information on the geometry of the betaCD/IMZ complex was obtained from ROESY spectroscopy, while the dynamics of the inclusion complex in the kilohertz range was obtained from the proton spin-lattice relaxation times in the rotating frame, T(1rho) (1H). PMID:14553984

2003-10-10

230

III-phosphides heterojunction solar cell interface properties from admittance spectroscopy  

International Nuclear Information System (INIS)

GaInP solar cell interfaces were characterized by admittance spectroscopy. Admittance spectroscopy is shown to be sensitive to the band structure at the heterojunction interfaces. In particular, a correlation between activation energy of the capacitance step in a capacitance versus temperature plot and effective potential barrier for majority carriers is demonstrated, indicating a new method for the determination of potential barriers at heterointerfaces. Using this technique, the effective potential barrier for holes at the p-Al_0_._5_3In_0_._4_7P/p-GaAs interface is found to be equal to 0.6 eV. Effects of interface defects and spreading resistance in the emitter of solar cells are illustrated and discussed.

2009-08-21

231

Characterisation and use of biomass fly ash in cement-based materials  

British Library Electronic Table of Contents (United Kingdom)

This paper presents results about the characterisation of the biomass fly ashes sourced from a thermal power plant and from a co-generation power plant located in Portugal, and the study of new cement formulations incorporated with the biomass fly ashes. The study includes a comparative analysis of the phase formation, setting and mechanical behaviour of the new cement-fly ash formulations based on these biomass fly ashes. Techniques such as X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), thermal gravimetric and differential thermal analysis (TG/DTA), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and environmental scanning electron spectroscopy (ESEM) were used to determine the structure and composition of the formulations. Fly ash F1 from the t...

2009-01-01

232

Andreev reflection spectroscopy of MgB{sub 2} in the vortex state  

Energy Technology Data Exchange (ETDEWEB)

Spectroscopy based on the Andreev reflection (AR) process at the interface between the normal metal tip and the superconductor has become one of the very successful methods for studies in novel exotic superconductors. The method is capable to address the size, symmetry as well as multiplicity of the superconducting order parameter. The method provided one of the first evidences of the two-gap superconductivity in MgB{sub 2} with a detailed temperature dependence of the both gaps. A theory treating the Andreev reflection spectroscopy in the mixed state is missing. We analyse the AR spectra of MgB{sub 2} in the mixed state via modelling the magnetic pair-breaking by the increasing spectral broadening parameter {gamma}. As a result a non-trivial pair breaking effect in the {pi}-band is found.

2004-05-01

233

Unconstrained energy functionals for electronic structure calculations  

Energy Technology Data Exchange (ETDEWEB)

The performance of conjugate gradient schemes for minimizing unconstrained energy functionals in the context of electronic structure calculations is studied. The unconstrained functionals allow a straightforward application of conjugate gradients by removing the explicit orthonormality constraints on the quantum-mechanical wave functions. However, the removal of the constraints can lead to slow convergence, in particular when preconditioning is used. The convergence properties of two previously suggested energy functionals are analyzed, and a new functional is proposed, which unifies some of the advantages of the other functionals. A numerical example confirms the analysis.

1998-04-01

234

Atomic density functions: atomic physics calculations analyzed with methods from quantum chemistry  

CERN Document Server

This contribution reviews a selection of findings on atomic density functions and discusses ways for reading chemical information from them. First an expression for the density function for atoms in the multi-configuration Hartree--Fock scheme is established. The spherical harmonic content of the density function and ways to restore the spherical symmetry in a general open-shell case are treated. The evaluation of the density function is illustrated in a few examples. In the second part of the paper, atomic density functions are analyzed using quantum similarity measures. The comparison of atomic density functions is shown to be useful to obtain physical and chemical information. Finally, concepts from information theory are introduced and adopted for the comparison of density functions. In particular, based on the Kullback--Leibler form, a ...

2011-01-01

235

Tissue oxygenation in a murine SCC VII tumor after X-ray irradiation as determined by EPR spectroscopy  

UK PubMed Central (United Kingdom)

PurposeThe goal of this study was to clarify the dynamics of tumor oxygen (partial pressure of oxygen, pO2) in SCC VII murine tumors in mice after X-ray...Full Text Available

2008-03-01

236

Temperature and current coefficients of lasing wavelength in tunable diode laser spectroscopy  

UK PubMed Central (United Kingdom)

The factors determining temperature and current coefficients of lasing wavelength are investigated and discussed under monitoring CO2-gas absorption spectra. The diffusion rate of...Full Text Available

2010-08-01

237

Teaching electron diffraction and imaging of macromolecules.  

UK PubMed Central (United Kingdom)

Electron microscopic analysis can be used to determine the three-dimensional structures of macromolecules at resolutions ranging between 3 and 30 A. It differs from nuclear magnetic resonance spectroscopy...Full Text Available

1993-05-01

238

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

International Nuclear Information System (INIS)

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

1975-01-01

239

Spectroscopic studies of the type 2 and type 3 copper centres in the mercury derivative of laccase.  

UK PubMed Central (United Kingdom)

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

1989-10-15

240

Solid-state 13C NMR spectroscopy of a 13C carbonyl-labeled polypeptide  

UK PubMed Central (United Kingdom)

High resolution structural elucidation of macromolecular structure by solid-state nuclear magnetic resonance requires the preparation of uniformly aligned samples that are isotopically labeled. In...Full Text Available

1992-06-01

241

Simulation study of chiral two dimensional ultraviolet (2DUV) spectroscopy of the protein backbone  

UK PubMed Central (United Kingdom)

Amide n –π* and π-π* excitations around 200 nm are prominent spectroscopic...Full Text Available

2010-06-09

242

Semiconductor Radiation Detectors with Frisch Collars and Collimators for Gamma Ray Spectroscopy and Imaging  

Energy Technology Data Exchange (ETDEWEB)

To study CdZnTe as a high energy resolution gamma ray detector with a novel new design, and to build a detector array from the new detector design

2006-12-04

243

SIDE GROUP ADDITION TO THE PAH CORONENE BY UV PHOTOLYSIS IN COSMIC ...  

Science.gov (United States)

a CsI window (for IR spectroscopy)andinto which the PAH wasisolated(Hudgins& ... I j.trnthick after30minutes,andtypically hadH20/PAH ratiosof ...

244

Role of Methoxypolyethylene Glycol on the Hydration, Activity, Conformation and Dynamic Properties of a Lipase in a Dry Film  

UK PubMed Central (United Kingdom)

A combined approach based on the use of ATR-FT/IR and steady-state fluorescence spectroscopy allowed to shed light on the effects of the additive methoxypolyethylene glycol (MePEG) on the hydration,...Full Text Available

2008-10-01

245

Quantification of "2"3"5U and "2"3"8U activity concentrations for undeclared nuclear materials by a digital gamma-gamma coincidence spectroscopy  

International Nuclear Information System (INIS)

The purpose of this study is to investigate the possibility of verifying depleted uranium (DU), natural uranium (NU), low enriched uranium (LEU) and high enriched uranium (HEU) by a developed digital gamma-gamma coincidence spectroscopy. The spectroscopy consists of two NaI(Tl) scintillators and XIA LLC Digital Gamma Finder (DGF)/Pixie-4 software and card package. The results demonstrate that the spectroscopy provides an effective method of "2"3"5U and "2"3"8U quantification based on the count rate of their gamma-gamma coincidence counting signatures. The main advantages of this approach over the conventional gamma spectrometry include the facts of low background continuum near coincident signatures of "2"3"5U and "2"3"8U, less interference from other radionuclides by the gamma-gamma coincidence counting, and region-of-interest (ROI) imagine analysis for uranium enrichment determination. Compared to conventional gamma ...

2011-06-01

246

Probing the Mechanisms of an Air Amplifier using a LTQ-FT-ICR-MS and Fluorescence Spectroscopy  

UK PubMed Central (United Kingdom)

We report the first quantitative assessment of electrosprayed droplet/ion focusing enabled by the use of a voltage-assisted air amplifier between an electrospray ionization emitter and a hybrid...Full Text Available

2007-11-01

247

Photophysics and optical switching in green fluorescent protein mutants  

UK PubMed Central (United Kingdom)

We demonstrate by using low-temperature high-resolution spectroscopy that red-shifted mutants of green fluorescent protein are photo-interconverted among three conformations and are, therefore, not...Full Text Available

2000-03-28

248

Photoelectron spectroscopy of carbonyls: benzoic acid and its derivatives  

Energy Technology Data Exchange (ETDEWEB)

The ultraviolet photoelectron spectra of benzoic acid and 20 of its derivatives are presented. The low-energy regions of these spectra are deconvoluted and assigned using chemical substitution effects. 5 figures, 3 tables.

1981-01-01

249

New approach to study fast and slow motions in lipid bilayers: application to dimyristoylphosphatidylcholine-cholesterol interactions.  

UK PubMed Central (United Kingdom)

Natural abundance 13C solid-state nuclear magnetic resonance spectroscopy was used to investigate the effect of the incorporation of cholesterol on the dynamics of dimyristoylphosphatidylcholine (DMPC)...Full Text Available

1995-05-01

250

Near-infrared spectroscopy technique to evaluate the effects of red blood cell transfusion on tissue oxygenation  

UK PubMed Central (United Kingdom)

IntroductionThe aim of this study was to evaluate the effects of red blood cell (RBC) transfusions on muscle tissue oxygenation, oxygen metabolism and microvascular reactivity in...Full Text Available

2009-01-01

251

Mechanism of the dissolution of coals in a mixture of concentrated sulfuric and nitric acids  

British Library Electronic Table of Contents (United Kingdom)

In this work, coals of various ranks were dissolved in an acid melange. With the use of IR spectroscopy, it was found that the mechanism of coal dissolution consists in the grafting of polar groups to the peripheral benzene rings of graphite-like systems.

2011-01-01

252

MAGIC - Multi Anode Gas Ionization Chamber  

Energy Technology Data Exchange (ETDEWEB)

A novel approach to the Bragg curve spectroscopy is utilized to construct a charged particle detector which makes fragment elemental identification and energy measurement possible. The advantage of the construction includes good timing and spectroscopic properties with a very low energy threshold. ((orig.))

1994-12-01

253

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

International Nuclear Information System (INIS)

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

254

In vivo study of chloroplast volume regulation.  

UK PubMed Central (United Kingdom)

This paper describes a new technique that can be used to study chloroplast volume regulation in vivo. Nuclear magnetic resonance spectroscopy was used to measure relative amounts of chloroplast water...Full Text Available

1992-05-01

255

Hydroxylation of 3-Nitrotyrosine and Its Derivatives by Gamma Irradiation  

Science.gov (United States)

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

256

Force-dependent chemical kinetics of disulfide bond reduction observed with single-molecule techniques  

UK PubMed Central (United Kingdom)

The mechanism by which mechanical force regulates the kinetics of a chemical reaction is unknown. Here, we use single-molecule force–clamp spectroscopy and protein engineering to study the effect...Full Text Available

2006-05-09

257

Examining the Phonological Neighborhood Density Effect Using Near Infrared Spectroscopy  

UK PubMed Central (United Kingdom)

Phonological density refers to the number of words that can be generated by replacing a phoneme in a target word with another phoneme in the same position. Although the precise nature of the...Full Text Available

2011-09-01

258

Evaluation of passive films by photo and impedance spectroscopy; Bunkoho oyobi inpidansu ho ni yoru himaku hyoka  

Energy Technology Data Exchange (ETDEWEB)

The passive films formed on iron metal, alloys or stainless steel are extremely thin oxides or hydroxides and possess the properties of high chemical stability in the environment. These films show characteristics interested both electrical as well as electrochemical point of view due to the thin thickness of the films. Auger Electron Spectroscopy, X-ray Photoelectron spectroscopy and so on which are the conventional electrochemical measurement methods or the surface analysis methods are used for the analysis and evaluation of these films, however, at present, the application of research technique focusing the superconductor characteristics of the films are tried. Although, the potential modulation reflection spectroscopy method has merits like possibility of in-situ measurement, high precision, possibility of stable analysis even for extremely thin film and so forth, it has also demerits like difficulty to response the ...

1995-09-20

259

Energy metabolism of the untrained muscle of elite runners as observed by 31P magnetic resonance spectroscopy: evidence suggesting a genetic endowment for endurance exercise.  

UK PubMed Central (United Kingdom)

The purpose of this study was to investigate whether genetically determined properties of muscle metabolism contribute to the exceptional physical endurance of world-class distance runners. ATP, phosphocreatine,...Full Text Available

1988-12-01

260

Electron spin resonance studies of radiation effects in biological materials. An assessment of current and future research  

Energy Technology Data Exchange (ETDEWEB)

Electron spin resonance spectroscopy can provide a powerful approach to the study of radiation effects in biological materials. This memorandum gives an overview of current and future research. (author).

1987-06-01

261

Electron Spin Resonance Studies of Ionic Permeability Properties of Thylakoid Membranes of Beta vulgaris and Avicennia germinans1  

UK PubMed Central (United Kingdom)

Measurement of intrathylakoid aqueous volumes by electron spin resonance spectroscopy was used to study ionic permeability properties of thylakoid membranes isolated from Beta vulgaris...Full Text Available

1985-05-01

262

Developments of heavy-ion gas detectors at LNL  

Energy Technology Data Exchange (ETDEWEB)

The most important developments in gaseous detectors at LNL are reviewed. Some aspects of timing, pulse height and position resolutions of avalanche counters are reported. The experimental work on heavy-ion identification by Bragg curve spectroscopy is summarized.

1984-05-01

263

Current Role and Future Perspectives of Magnetic Resonance Spectroscopy in Radiation Oncology for Prostate Cancer  

UK PubMed Central (United Kingdom)

Prostatic neoplasms are not uniformly distributed within the prostate volume. With recent developments in three-dimensional intensity-modulated and imageguided radiation therapy, it is possible to treat...Full Text Available

2007-06-01

264

Correlations between surface structure and catalytic activity/selectivity  

Energy Technology Data Exchange (ETDEWEB)

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

1990-11-01

267

Characterization and catalytic oxidation activity of uranium-bismuth mixed oxides  

International Nuclear Information System (INIS)

Bi-U mixed oxides were synthesized by two methods and characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The samples were tested for the catalytic oxidation of carbon monoxide by oxygen. A stepwise redox mechanism consistent with the kinetic results is proposed. (orig.).

268

Anaerobic reactions of Rhus vernicifera laccase and its type-2 copper-depleted derivatives with hexacyanoferrate(II).  

UK PubMed Central (United Kingdom)

Anaerobic reactions of Rhus vernicifera laccase and its type-2 copper-depleted derivatives with hexacyanoferrate(II) were investigated by absorption and e.s.r. spectroscopy. When native laccase was...Full Text Available

1992-06-15

269

The closure operator in a multivalued logic based on functional equations  

British Library Electronic Table of Contents (United Kingdom)

An operator of FE-closure is introduced on the set of functions of a multivalued logic based on the systems of functional equations. It is proved that, for every k ? 2, the FE-closure operator generates a finite classification on the set P k of functions of k-valued logic. The least class in this classification is shown to be the class H k of all homogeneous functions. Also a series of corollaries are obtained concerning the finite FE-generating sets in the FE-closed classes.

2011-01-01

270

Finding the best quadratic approximation of a function  

British Library Electronic Table of Contents (United Kingdom)

This article examines the question of finding the best quadratic function to approximate a given function on an interval. The prototypical function considered is f(x) = ex. Two approaches are considered, one based on Taylor polynomial approximations at various points in the interval under consideration, the other based on the fact that three non-collinear points determine a unique quadratic function. Three different techniques for measuring the error in the approximations are considered.

2011-01-01

271

[Experimental and kinetic modeling of acid/base and redox reactions over oxide catalysts  

Energy Technology Data Exchange (ETDEWEB)

The research has involved the characterization of catalyst acidity, [sup 2]D NMR studies of Bronsted acid sites, and kinetic, calorimetric, and spectroscopic studies of methylamine synthesis and related reactions over acid catalysts. Approach of this work was to explore quantitative correlations between factors that control the generation, type, strength, and catalytic properties of acid sites on zeolite catalysts. Microcalorimetry, thermogravimetric analysis, IR spectroscopy, and NMR spectroscopy have provided information about the nature and strength of acid sites in zeolites. This was vital in understanding the catalytic cycles involved in methylamine synthesis and related reactions over zeolite catalysts.

1993-01-01

272

Vibrational spectroscopy of silica sol-gel components during microwave irradiation  

Energy Technology Data Exchange (ETDEWEB)

In order to study the effects of microwaves on chemical reactions equipment was designed to acquire in-situ vibrational spectra of sol-gel components as they are irradiated with microwaves. Fourier Transform Infrared (FTIR) and Raman spectroscopy were used. A low temperature (10K) FTIR cell was used to trap samples in an argon matrix at 10{sup -7} Torr. For the liquid samples no differences were seen in spectra of irradiated and nonirradiated samples, but the argon matrix isolation technique showed dramatic differences.

1995-12-31

273

Towards Antihydrogen Trapping and Spectroscopy at ALPHA  

CERN Document Server

Spectroscopy of antihydrogen has the potential to yield high-precision tests of the CPT theorem and shed light on the matter-antimatter imbalance in the Universe. The ALPHA antihydrogen trap at CERN's Antiproton Decelerator aims to prepare a sample of antihydrogen atoms confined in an octupole-based Ioffe trap and to measure the frequency of several atomic transitions. We describe our techniques to directly measure the antiproton temperature and a new technique to cool them to below 10 K. We also show how our unique position-sensitive annihilation detector provides us with a highly sensitive method of identifying antiproton annihilations and effectively rejecting the cosmic-ray background.

2011-01-01

274

Spectroscopy of color centers in yttrium-aluminium perovskite crystals  

International Nuclear Information System (INIS)

The color centers, which are generated in yttrium-aluminium perovskite (YAP):Nd(1 at.%) and YAP:Er(50 at.%) crystals under the influence of ultraviolet and #gamma#-irradiation, have been studied by absorption spectroscopy. The generated color centers are both stable and transient at room temperature. It is shown that the transient color centers are mainly responsible for the decrease of laser generation efficiency of Nd:YAP and YAP:Er irradiated crystals, although physical mechanisms leading to efficiency decrease are different in these materials. (orig.)

1998-07-24

275

Results from the photoemission spectroscopy beamline 2B1 at Pohang Light Source  

Energy Technology Data Exchange (ETDEWEB)

The results of photoemission spectroscopy using molybdenum and tantalum samples have been obtained from the new beamline 2B1 at Pohang Light Source. Beamline 2B1 is based on a spherical grating monochromator (SGM) which is equipped with five gratings. The photon energy range from 184 to 1100 eV was covered in this work using two gratings (Gratings 4 and 5). The photon energy resolution has been deduced from Ta Fermi-level spectra and 3d spectra of Mo.

1999-06-01

276

Preliminary Design of ARIES-Devasthal Faint Object Spectrograph and Camera  

CERN Document Server

We present here the preliminary design of ARIES-Devasthal Faint Object Spectrograph and Camera (ADFOSC), which is a multi-mode instrument for both imaging and spectroscopy. ADFOSC is the first-generation instrument to be mounted at the axial port of the Cassegrain focus on our new 3.6m optical telescope to be installed at Devasthal, Nainital. The main design goals of the instrument are : the instrument will have capability of broad- and narrow-band imaging, low-medium resolution spectroscopy, and imaging polarimetry. The operating wavelength range will be from 360 to 1000 nm and the instrument will have remote-control capability.

2009-01-01

277

Nuclear spectroscopy, ch. 8  

International Nuclear Information System (INIS)

Energy level schemes are derived from gamma spectroscopy of several medium-mass deformed nuclei by studying the decay or proton and #alpha# nuclear spectroscopic data. Some new isomeric studies are established among which is the 31 y "1"7"8Hf isomeric state for which Isup(#pi#), K was determined to be 16"+, 16. A four quasi-particle configuration was assigned to this state at 2447.5 +- 2.5 KeV. Atomic masses have been calculated from various measurements and, on the basis of mass formulae extrapolated to neighboring mass regions.

278

Moessbauer spectroscopy study of iron corrosion underneath painting system  

International Nuclear Information System (INIS)

The effect of pigments on the development of corrosion products between the painting system and metal surface when exposed to marine environments has been discussed. The pigments studied were: red mud zinc chromate, zinc chromate, red oxide zinc phosphate, manganese phosphate barium chromate and basic lead silico chromate. Moessbauer spectroscopy revealed that the upper rust layer in all the cases consisted of #gamma#-Fe_2O_3, #gamma#-FeOOH and #alpha#-FeOOH. The lower rust layer immediately in contact with the metal surface consisted of an asymmetrical doublet due to #gamma#-FeOOH. (Auth.).

279

Measurement of AlP/GaP (001) heterojunction band offsets by x-ray photoemission spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

X-ray photoemission spectroscopy has been used to measure the valence band offset {Delta}E{sub v} for the AlP/GaP (001) heterojunction interface. The heterojunction samples were prepared by molecular-beam epitaxy. A value of {triangle}E{sub v}=0.43 eV is obtained (staggered band alignment, with AlP valence band below that of GaP). 24 refs., 8 figs., 1 tab.

1993-07-01

280

Infrared spectroscopy analysis of MgO-doped silicon nitride  

Energy Technology Data Exchange (ETDEWEB)

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

1997-12-31

281

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

International Nuclear Information System (INIS)

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

282

Evidence for excess vacancy defects in the Pd-Si system: positron annihilation, x-ray diffraction and Auger electron spectroscopy study  

Energy Technology Data Exchange (ETDEWEB)

The transformation of Pd/Si to Pd{sub 2}Si/Si is investigated using depth-resolved positron annihilation, x-ray diffraction and Auger electron spectroscopy studies. The observed defect-sensitive positron S-parameter value of 1.022-1.054 indicates the existence of divacancies across the silicide/silicon interface and Si substrate region. Our experimental observation of vacancy defects is consistent with the model proposed for excess vacancy generation across the interface consequent to Si diffusion. (letter to the editor)

2003-11-26

283

Development of the SRS environmental counting laboratory gamma spectroscopy system  

International Nuclear Information System (INIS)

The Savannah River Site (SRS), one of several U.S. Department of Energy (DOE) facilities, produces nuclear materials for national defense and for other government and civilian uses. SRS ceased production of defense materials in 1988, and the site's main activities now involve waste management and environmental restoration. These programs have generated extensive effluent monitoring and environmental surveillance programs for the Environmental Monitoring Section (EMS), which performs #approx#105,000 radiological analyses on 30,000 samples a year. Gamma spectroscopy is performed on an estimated 10,000 samples annually. This report describes a program to develop and improve the EMS system.

1996-06-16

284

Development of advanced electrochemical emission spectroscopy for monitoring corrosion in simulated DOE liquid waste. 1998 annual progress report  

Energy Technology Data Exchange (ETDEWEB)

'Objective of this project is to develop and use Electrochemical Emission Spectroscopy (EES) and other electrochemical techniques as in situ tools for exploring corrosion mechanisms of iron and carbon steel in highly alkaline solutions and for continuously monitoring corrosion on structural materials in DOE liquid waste storage system. In particular, the author will explore the fundamental aspects of the passive behavior of pure iron since breakdown of passivity leads to localized corrosion. This report summarizes work after 1 year of a 3 year project.'

1998-06-01

285

Comparative study of passive films of different stainless steels developed on alkaline medium  

International Nuclear Information System (INIS)

Evolution of the passive films formed on AISI 304L and duplex stainless steel SAF 2205 in NaOH 0.1 M was investigated using cyclic voltammetry, electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS). Special attention is paid to the effect of Mo in the generation of the films. Results point out to the stabilising effect of the molybdates on the surface of the film, enhancing the formation of a thin layer on the SAF 2205 with a higher Cr/Fe ratio.

2004-07-30

286

Analysis of o-tyrosine as a method for the identification of irradiated chicken and the comparison with other methods (analysis of volatiles and ESR-spectroscopy)  

Energy Technology Data Exchange (ETDEWEB)

With the mentioned method to analyse O-tyrosine with HPLC/fluorescence-detection, the irradiation of chicken meat can be determined in a simple and fast way. The formation of o-tyrosine is proportional to the applied dose but because it is also depending on the applied dose rate and the temperature during the irradiation, it is not possible to control the irradiation dose. Since unirradiated chicken can contain little amounts of o-tyrosine and to confirm some results, a second method is needed. Together with one of the other mentioned methods (analysis of the volatiles or esr-spectroscopy) it is possible to recognize irradiated chicken with a high security. (author).

1990-01-01

287

Mass and charge transfer on various relevant scales in polymer electrolyte fuel cells[Dissertation 16991  

Energy Technology Data Exchange (ETDEWEB)

This dissertation is concerned with the development, experimental diagnostics and mathematical modelling and simulation of polymer electrolyte fuel cells (PEFC). The central themes throughout this thesis are the closely interlinked phenomena of mass and charge transfer. In the face of developing a PEFC system for vehicle propulsion these phenomena are scrutinized on a broad range of relevant scales. Starting from the material related level of the membrane and the gas diffusion layer (GDL) we turn to length scales, where structural features of the cell additionally come into play. These are the scale of flow channels and ribs, the single cell and the cell stack followed by the cell, stack, and system development for an automotive power train. In Chapter 3 selected fundamental material models and properties, respectively, are explored that are crucial for the mathematical modelling and simulation of PEFC, as needed in some succeeding parts of this work. First, established mathematical ...

2007-07-01

288

Comparative study of different methodologies for quantitative rock analysis by Laser-Induced Breakdown Spectroscopy in a simulated Martian atmosphere  

Energy Technology Data Exchange (ETDEWEB)

Laser-Induced Breakdown Spectroscopy was selected by NASA as part of the ChemCam instrument package for the Mars Science Laboratory rover to be launched in 2009. ChemCam's Laser-Induced Breakdown Spectroscopy instrument will ablate surface coatings from materials and measure the elemental composition of underlying rocks and soils at distances from 1 up to 10 m. The purpose of our studies is to develop an analytical methodology enabling identification and quantitative analysis of these geological materials in the context of the ChemCam's Laser-Induced Breakdown Spectroscopy instrument performance. The study presented here focuses on several terrestrial rock samples which were analyzed by Laser-Induced Breakdown Spectroscopy at an intermediate stand-off distance (3 m) and in an atmosphere similar to the Martian one (9 mbar CO{sub 2}). The experimental results highlight the matrix effects ...

2006-03-15

289

Comparative study of different methodologies for quantitative rock analysis by Laser-Induced Breakdown Spectroscopy in a simulated Martian atmosphere  

International Nuclear Information System (INIS)

Laser-Induced Breakdown Spectroscopy was selected by NASA as part of the ChemCam instrument package for the Mars Science Laboratory rover to be launched in 2009. ChemCam's Laser-Induced Breakdown Spectroscopy instrument will ablate surface coatings from materials and measure the elemental composition of underlying rocks and soils at distances from 1 up to 10 m. The purpose of our studies is to develop an analytical methodology enabling identification and quantitative analysis of these geological materials in the context of the ChemCam's Laser-Induced Breakdown Spectroscopy instrument performance. The study presented here focuses on several terrestrial rock samples which were analyzed by Laser-Induced Breakdown Spectroscopy at an intermediate stand-off distance (3 m) and in an atmosphere similar to the Martian one (9 mbar CO2). The experimental results highlight the matrix effects and the measurement ...

2006-03-01

290

Target organs and systems: methodologies to assess immune system function.  

UK PubMed Central (United Kingdom)

Immunotoxicity encompasses both reduced and heightened immune function. Diverse chemicals can impair functioning of the immune system. Both monographs and books have been devoted to detailed descriptions...Full Text Available

1998-04-01

291

Structure functions of nuclei in fluctonic model with rescaling  

International Nuclear Information System (INIS)

It is shown that the available data on x, Q"2, and A dependence of nuclear structure functions and for their ratios (EMS effect) can be described in terms of the flucton model with rescaling of parton distributions in nuclei. The x, Q"2 and A dependence of nuclear structure functions in the cumulative range (x >1) is predicted.

292

Structural formulae for some classes of analytic functions in a finitely connected domain  

Science.gov (United States)

Several central results of the method of structural formulae for some classes of analytic functions, which were known before for a disc and an annulus, are generalized to analytic functions in a finitely connected circular domain.

1997-12-01

293

Pulmonary Function and the Risk of Functional Limitation in Chronic Obstructive Pulmonary Disease  

UK PubMed Central (United Kingdom)

The authors’ objective was to analyze the impact of respiratory impairment on the risk of physical functional limitations among adults with chronic obstructive pulmonary disease (COPD)....Full Text Available

2008-05-01

294

Pharmacologically Induced Hypogonadism and Sexual Function in Healthy Young Women and Men  

UK PubMed Central (United Kingdom)

Studies fail to find uniform effects of age-related or induced hypogonadism on human sexual function. We examined the effects of induced hypogonadism on sexual function in healthy men and women...Full Text Available

2009-02-01

295

On the construction of approximations to continuous functions under integral boundary conditions  

British Library Electronic Table of Contents (United Kingdom)

On the basis of the resolvent of a simple differential operator, a method for finding approximations to continuous functions is constructed. In this method, both the approximated function and its approximations satisfy the given integral boundary condition.

2011-01-01

296

Initial Report of the Cancer PROMIS Supplement Sexual Function Committee: Review of Sexual Function Measures and Domains Used in Oncology  

UK PubMed Central (United Kingdom)

ObjectiveThis report describes initial activities of the Cancer Patient-Reported Outcomes Measurement Information System (PROMIS) Sexual Function domain group (CaPS-SF),...Full Text Available

2009-03-15

297

Increased wind-up to heat pain in women with a childhood history of functional abdominal pain  

UK PubMed Central (United Kingdom)

Idiopathic or functional abdominal pain (FAP) is common in school-age children and typically reflects a functional gastrointestinal disorder (FGID). FGIDs in adults have been distinguished by...Full Text Available

2011-04-01

298

Characterization of the functional gene and several processed pseudogenes in the human triosephosphate isomerase gene family.  

UK PubMed Central (United Kingdom)

The functional gene and three intronless pseudogenes for human triosephosphate isomerase were isolated from a recombinant DNA library and characterized in detail. The functional gene spans 3.5 kilobase...Full Text Available

1985-07-01

299

Challenges of functional imaging research of pain in children  

UK PubMed Central (United Kingdom)

Functional imaging has revolutionized the neurosciences. In the pain field it has dramatically altered our understanding of how the brain undergoes significant functional, anatomical and chemical changes...Full Text Available

300

Program functionality and information analysis  

Energy Technology Data Exchange (ETDEWEB)

The Office of Civilian Radioactive Waste Management (OCRWM) is executing a plan for improvement of the United States Nuclear Waste Management Program. As part of the plan, OCRWM is performing a systems engineering analysis of both the physical system, i.e., the Nuclear Waste Management System (NWMS), and the programmatic functions that must be accomplished to bring the physical system into being. The functional analysis effort is being performed by two separate teams working in parallel, one of which addresses the physical system functions and the other the programmatic functions. This paper presents information on the analysis of the programmatic functions.

1992-04-01

301

Tensors, spinors, and functions on the unit sphere  

International Nuclear Information System (INIS)

A representation of tensors and spinors at a point of space-time as spin and conformally weighted functions on the unit sphere is derived. Methods for performing algebraic operations on tensors and spinors in this representation are discussed. (author).

302

Structural and operational complexity of the Geobacter sulfurreducens genome  

UK PubMed Central (United Kingdom)

Prokaryotic genomes can be annotated based on their structural, operational, and functional properties. These annotations provide the pivotal scaffold for understanding cellular functions on a genome-scale,...Full Text Available

2010-09-01

303

Sexual Function Before and After Sacrocolpopexy for Pelvic Organ Prolapse  

UK PubMed Central (United Kingdom)

ObjectiveTo describe sexual function before and after sacrocolpopexy.Study designIn the Colpopexy and Urinary Reduction...Full Text Available

2007-12-01

304

Power Analyzer for Pocket Computing (PAPC)  

Science.gov (United States)

... Those functions are fundamental routines to build a power model for more complex circuits or functional blocks. ... 21 of 54 6. Memory Power Model ...

2004-01-01

305

Posterior repair and sexual function  

UK PubMed Central (United Kingdom)

OBJECTIVEThe purpose of this study was to determine the effect of posterior repair (PR) on sexual function in patients who have undergone incontinence and/or pelvic...Full Text Available

2007-07-01

306

Polyphenols and Aging  

UK PubMed Central (United Kingdom)

Age-associated changes within an individual are inherently complex and occur at multiple levels of organismal function. The overall decline in function of various tissues is known to play a...Full Text Available

2010-02-01

307

On the A-dependence of the nuclear structure functions  

International Nuclear Information System (INIS)

The A-dependence of the nuclear structure functions is described rather well within the framework of the quark-parton-flucton model of nucleus. 16 refs. (author).

308

Morphology and function of the forelimb in arboreal frogs: specializations for grasping ability?  

UK PubMed Central (United Kingdom)

Frogs are characterized by a unique morphology associated with their saltatory lifestyle. Although variation in the form and function of the pelvic girdle and associated appendicular system related...Full Text Available

2008-09-01

310

Impact on sexual function after reconstructive surgery for anterior urethral stricture disease  

UK PubMed Central (United Kingdom)

Objective:To evaluate the effect of urethral reconstructive surgery on sexual drive, erectile function and ejaculation.Materials and Methods:The...Full Text Available

2010-04-01

311

Imbibition of Swietenia macrophylla (Meliaceae) Seeds: The Role of Stomata  

UK PubMed Central (United Kingdom)

• Background and Aims The occurrence of stomata in seed coats is uncommon and there is limited information about their function(s). The aim of this study was to verify the distribution...Full Text Available

2006-07-01

312

Gallbladder function and dynamics of bile flow in asymptomatic gallstone disease  

UK PubMed Central (United Kingdom)

AIM: To investigate the effects of gallbladder stones on motor functions of the gallbladder and the dynamics of bile flow in asymptomatic gallstone disease.METHODS: Quantitative hepatobiliary...Full Text Available

2009-06-14

313

Filtered Density Function for Subgrid Scale Modeling of ...  

Science.gov (United States)

... Compilation Part Notice ADP023645 TITLE: Filtered Density Function for Subgrid Scale Modeling of Turbulent Diffusion Flames ...

2006-06-01

314

Effect of ginger on gastric motility and symptoms of functional dyspepsia  

UK PubMed Central (United Kingdom)

AIM: To evaluate the effects of ginger on gastric motility and emptying, abdominal symptoms, and hormones that influence motility in dyspepsia.METHODS: Eleven patients with functional dyspepsia...Full Text Available

2011-01-07

315

ERG Expression Levels in Prostate Tumors Reflect Functional ...  

Science.gov (United States)

... Title : ERG Expression Levels in Prostate Tumors Reflect Functional Status of the Androgen Receptor (AR) as a Consequence of Fusion of ERG ...

316

Association of upper gastrointestinal symptoms with functional and clinical charateristics in elderly  

UK PubMed Central (United Kingdom)

AIM: To evaluate the prevalence of upper gastrointestinal symptoms and their association with clinical and functional characteristics in elderly outpatients.METHODS: The study involved 3238 outpatients...Full Text Available

2011-07-07

317

'Sixth root of unity' and Feynman diagrams: hypergeometric function approach point of view  

International Nuclear Information System (INIS)

We briefly discuss the transcendental constants generated through the #epsilon# expansion of generalized hypergeometric functions and their interrelation with the 'sixth root of unity.'

2010-04-25

320

The generating function of amplitudes with N twisted and M untwisted states  

CERN Document Server

We show that the generating function of all amplitudes with N twisted and M untwisted states, i.e. the Reggeon vertex for magnetized branes on R^2 can be computed once the correlator of N non excited twisted states and the corresponding Green function are known and we give an explicit expression as a functional of the these objects

2011-01-01

330

Optimal Knot Selection for Least-squares Fitting of Noisy Data with Spline Functions  

Energy Technology Data Exchange (ETDEWEB)

An automatic data-smoothing algorithm for data from digital oscilloscopes is described. The algorithm adjusts the bandwidth of the filtering as a function of time to provide minimum mean squared error at each time. It produces an estimate of the root-mean-square error as a function of time and does so without any statistical assumptions about the unknown signal. The algorithm is based on least-squares fitting to the data of cubic spline functions.

2008-05-15

333

Gauge fixing, infrared divergences and confinement  

Energy Technology Data Exchange (ETDEWEB)

The generating functional in which the residual gauge freedom has been broken is related to the conventional generating functional for QED in arbitrary dimension. Closed expressions which relate ordinary N-point Green functions to N-point Green functions in the different gauges are derived. The leading logarithmic behaviour of the electron propagator in three dimensions is thus obtained. It is argued that one should not ascribe much importance to the infrared behaviour of the fermion propagator in the context of confinement.

1984-09-27

339
340

Chromatic quasisymmetric functions and Hessenberg varieties  

CERN Document Server

We discuss three distinct topics of independent interest; one in enumerative combinatorics, one in symmetric function theory, and one in algebraic geometry. The topic in enumerative combinatorics concerns a q-analog of a generalization of the Eulerian polynomials, the one in symmetric function theory deals with a refinement of the chromatic symmetric functions of Stanley, and the one in algebraic geometry deals with Tymoczko's representation of the symmetric group on the cohomology of the regular semisimple Hessenberg variety of type A. Our purpose is to explore some remarkable connections between these topics.

2011-01-01

343

Evaluating Point Forecasts  

CERN Document Server

Typically, point forecasting methods are compared and assessed by means of an error measure or scoring function, such as the absolute error or the squared error. The individual scores are then averaged over forecast cases, to result in a summary measure of the predictive performance, such as the mean absolute error or the (root) mean squared error. I demonstrate that this common practice can lead to grossly misguided inferences, unless the scoring function and the forecasting task are carefully matched. Effective point forecasting requires that the scoring function be specified ex ante, or that the forecaster receives a directive in the form of a statistical functional, such as the mean or a quantile of the predictive distribution. If the scoring function is specified ex ante, the forecaster can issue the optimal point forecast, namely, the Bayes rule. If the forecaster receives a ...

2009-01-01

344

Hybrid Density Functional Studies of ?-Pu  

Science.gov (United States)

Hybrid density functionals, which replaces a fraction of a density functional theory exchange with exact Hartree-Fock (HF) exchange, have been used to study the structural, magnetic, and electronic properties of ?-Pu. The fractions of exact Hartree-Fock exchange used were 25%, 40%, and 55%. Compared to the pure PBE functional, the lattice constants expanded with respect to the experimental value when the PBE-HF hybrid functionals were applied. For pure PBE and hybrids functionals with HF exchange amounts of 25% and 40%, the ground state structure was anti-ferromagnetic, while for 55% HF contribution the ground state was non-magnetic. The 5f electrons tend to exhibit slight delocalization or itinerancy for the pure PBE functional and well-defined localization for the hybrid functionals, with the degree of 5f electron localization increasing ...

2009-03-01

345

Does hybrid density functional theory predict a non-magnetic ground state for ?-Pu?  

Science.gov (United States)

Hybrid density functionals, which replace a fraction of density functional theory (DFT) exchange with exact Hartree-Fock (HF) exchange, have been used to study the structural, magnetic, and electronic properties of ?-Pu. The fractions of exact Hartree-Fock exchange used were 25%, 40%, and 55%. Compared to the pure PBE functional, the lattice constants expanded with respect to the experimental value when the PBE-HF hybrid functionals were applied. For pure PBE and hybrid functionals with HF exchanges amounts of 25% and 40%, the ground state structure was anti-ferromagnetic, while for 55% HF contribution the ground state was non-magnetic. The 5f electrons tend to exhibit slight delocalization or itinerancy for the pure PBE functional and well-defined localization for the hybrid functionals, with the degree of 5f electron localization ...

2009-01-01

346

Does hybrid density functional theory predict a non-magnetic ground state for #delta#-Pu?  

International Nuclear Information System (INIS)

Hybrid density functionals, which replace a fraction of density functional theory (DFT) exchange with exact Hartree-Fock (HF) exchange, have been used to study the structural, magnetic, and electronic properties of #delta#-Pu. The fraction of exact Hartree-Fock exchange used were 25%, 40%, and 55%. Compared to the pure PBE functional, the lattice constants expanded with respect to the experimental value when the PBE-HF hybrid functionals were applied. For pure PBE and hybrid functionals with HF exchanges amounts of 25% and 40%, the ground state structure was anti-ferromagnetic, while for 55% HF contribution the ground state was non-magnetic. The 5f electrons tend to exhibit slight delocalization of itinerancy for the pure PBE functional and well-defined localization for the hybrid functionals, with the degree of 5f electron localization ...

2009-01-01

347

VDMA contribution to functional safety of turbo-machines - A necessary risk reduction by means of safety function for steam turbines; VDMA-Beitrag zur Funktionalen Sicherheit von Turbomaschinen. Notwendige Risikoreduktion durch Schutzfunktionen fuer Dampfturbinen  

Energy Technology Data Exchange (ETDEWEB)

In the last two years, the VDMA work group 'Functional security' compiled a qualitative and quantitative procedure for the determination and evaluation of turbo-machine specific risks. With the calibrated risk graph for turbo-machines the requirements (Safety Integrity Level SIL) to the protective functions for turbo-machines (steam turbines, gas turbines, generators and compressors) were determined. With consideration of the legislation, the work group compiled a recommendation for the renewal and/or reconstruction of protective functions with old facilities.

2010-07-01

348

Moving toward personalized cell-based interventions for adrenal cortical disorders: Part 1 - Adrenal development and function, and roles of transcription factors and signaling proteins  

British Library Electronic Table of Contents (United Kingdom)

Transdifferentiation of an individual's own cells into functional differentiated cells to replace an organ's lost function would be a personalized approach to therapeutics. In this two part series, we will describe the progress toward establishing functional transdifferentiated adrenal cortical cells. In this article (Part 1), we describe adrenal development and function, and discuss genes involved in these processess and selected for use in our pilot studies of transdifferentiation that are presented in the second article (Part 2).

2011-01-01

349

Functionalized luminescent oxide nanoparticles for sodium channel imaging at the single molecule level  

Science.gov (United States)

Lanthanide-ion doped oxide nanoparticles were functionalized for use as fluorescent biological labels. These nanoparticles are synthesized directly in water which facilitates their functionalization, and are very photostable without emission intermittency. Nanoparticles functionalized with guanidinium groups act as artificial toxins and specifically target sodium channels. They are individually detectable in cardiac myocytes, revealing a heterogeneous distribution of sodium channels. Functionalized oxide nanoparticles appear as a novel tool particularly well adapted to long-term single-molecule tracking.

2005-04-01

350

WR 104: Are We Looking Down The Gun Barrel of a Future GRB?  

Science.gov (United States)

WR 104 is the prototype for a small but growing group of stars that present the remarkably striking appearance of pinwheels. High resolution images of WR 104 show the (apparently) face-on spiral turning with an 8 month period. The pinwheel is assumed to be composed of dust produced via colliding winds in a low-inclination WR+OB binary. These assumptions have been very successful in modeling the imaging, but remain largely untested by spectroscopy. Strong motivation for further study of this system has emerged. Recent theory suggests that some gamma-ray bursts (GRB's) are core-collapse supernovae viewed nearly pole-on. The WC class Wolf-Rayet star in WR 104 is the type of star thought to be a possible GRB progenitor. If the orbit (and thus stellar rotation axes) are pole-on, the effects on Earth's biosphere could be significant. Confrontation of the face-on colliding-wind binary model with eight years of spectroscopy, offering full phase ...

2009-01-01

351

Thickness measurement of Sn-Ag hot dip coatings on Large Hadron Collider Superconducting strands by coulometry  

CERN Document Server

Amperostatic coulometry was applied for the thickness measurement of Sn-Ag hot dip coatings, which comprise an extended Sn-Cu interdiffusion layer. Complementary measurements, notably weight loss, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, X-ray fluorescence (XRF), and dynamic secondary ion mass spectroscopy were performed in order to obtain a better interpretation of the coulometry results. Based on the experimental results presented in this article, the three potential changes observed during coulometry measurements are ascribed to (i) the entire dissolution of pure Sn, (ii) the formation of a CuCl salt layer, and (iii) the surface passivation. The measurement of the pure Sn mass is well reproducible despite strong coating thickness variations detected by XRF. Several experimental problems, in particular, a coating undercutting, hamper the determination of the Sn mass in the intermetallic ...

2004-01-01

352

Study on the variations of molecular structures of some biomolecules induced by free electron laser using FTIR spectroscopy  

International Nuclear Information System (INIS)

In this study, free electron laser (FEL) with selective wavelength was used to induce structure changes of biomolecules, which were characterized by FTIR spectroscopy. For understanding of the interactions between FEL and biomolecules as well as biological tissues, the biomolecules investigated are ATP, ADP, AMP, t-RNA, D-ribose and the complex of SmCl_3-D-ribose. Their FTIR spectra before and after irradiation of FEL show molecular structure variations of the samples after irradiation of FEL, especially the rearrangement of their hydrogen bond networks. Along with the various irradiation wavelengths, irradiation time and molecular structures, the changes after irradiation are different for these molecules. In the FTIR spectra after irradiation, the phenomenon that the bands split into several peaks indicates the existence of several structures, conformations and configurations, which may be prompted by multiple photons process induced by FEL. After irradiation, ...

2007-05-01

353

Physico-chemical, optical and electrochemical properties of iron oxide thin films prepared by spray pyrolysis  

International Nuclear Information System (INIS)

Iron oxide thin films were prepared by spray pyrolysis technique onto glass substrates from iron chloride solution. They were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and (UV-vis) spectroscopy. The films deposited at T _s #<=# 450 deg. C were amorphous; while those produced at T _s_u_b = 500 deg. C were polycrystalline #alpha#-Fe_2O_3 with a preferential orientation along the (1 0 4) direction. By observing scanning electron microscopy (SEM), it was seen that iron oxide films were relatively homogeneous uniform and had a good adherence to the glass substrates. The grain size was found (by RX) between 19 and 25 nm. The composition of these films was examined by X-ray photoelectron spectroscopy and electron probe microanalysis (EPMA). These films exhibited also a transmittance value about 80% in the visible and infrared range. The cyclic ...

2006-12-15

354

Novel non-discoid chiral copper(II)-salen type [N2O2] donor Schiff base complexes with a cyclohexane diamine spacer: synthesis, electrochemistry, columnar mesomorphism and DFT study  

British Library Electronic Table of Contents (United Kingdom)

A series of new non-discoid chiral copper(ii)-salen type complexes, [Cu((4-CnH2n+1O)2salen)], n = 14, 16, 18 and salen = N,N'-cyclohexane bis (salicylideneiminato), containing 4-substituted alkoxy tails in the side aromatic rings and a cyclohexane spacer, have been prepared and their mesogenic properties investigated. The compounds were characterised by Fourier transform infra-red spectroscopy, 1H and 13C nuclear magnetic resonance spectroscopy, UV-vis spectroscopy and fast atom bombardment mass spectrometry. Mesomorphic properties of these compounds were studied by polarising optical microscopy, differential scanning calorimetry and X-ray diffraction (XRD). The ligands are non-mesogenic but the complexes exhibited enantiotropic rectangular columnar mesophases (Colr) with extended temperat...

2011-01-01

355

Monitoring interface traps in operating organic light-emitting diodes using impedance spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

Electronic trap densities at the indium tin oxide (ITO)/hole transport layer (HTL) interface in operating organic light-emitting diodes (OLEDs) are characterized in situ using impedance spectroscopy. For OLEDs with a high density of active trap states, negative values of the frequency derivative of resistance are clearly observable for frequencies on the order of 10 kHz, whereas positive values are observed when the trap density is low With this technique, it is revealed that the trap density is minimized via the introduction of a TPD-Si{sub 2} (4,4'-bis[(p-trichlorosilylpropylphenyl) phenylamino]-biphenyl) passivation layer at the ITO/HTL interface or by the application of large electric fields during device operation. Furthermore, impedance spectroscopy illustrates that the ITO/HTL interface is not a simple series resistance when traps are present since they are shown not to contribute to high frequency conduction. Overall, this ...

2007-04-09

356

Inverse spinel materials. A new class of high voltage cathode materials for Li-ion batteries  

Energy Technology Data Exchange (ETDEWEB)

The influence of Cr on the structure and electrochemical properties of LiCoVO{sub 4} was studied using X-Ray diffraction, scanning electron microscopy, Raman Spectroscopy and cycle tests. Doping levels up to 10 mol% were achieved, which improved the electrochemical stability of the structure of LiCoVO{sub 4}, resulting in a significant increase in the initial charge and discharge capacity. The Raman spectroscopy data for the Cr-doped LiCoVO{sub 4} is similar as for LiCoVO{sub 4}. The replacement of a dopant for the Co-ion in the inverse spinel structure causes several Raman shifts. The X-ray diffraction patterns show no new phases and combined with the Raman spectroscopy data it is concluded that the Cr dopant will be located at the octahedral site (16d) where they create an electronic pathway that enhances the electronic conductivity. However, the capacity dropped significantly after prolonged cycling, which is due to the ...

2003-07-01

357

Infrared Observations During the Secondary Eclipse of HD 209458b I. 3.6-Micron Occultation Spectroscopy Using the VLT  

CERN Document Server

We search for an infrared signature of the transiting extrasolar planet HD 209458b during secondary eclipse. Our method, which we call `occultation spectroscopy,' searches for the disappearance and reappearance of weak spectral features due to the exoplanet as it passes behind the star and later reappears. We argue that at the longest infrared wavelengths, this technique becomes preferable to conventional `transit spectroscopy'. We observed the system in the wing of the strong nu-3 band of methane near 3.6 microns during two secondary eclipses, using the VLT/ISAAC spectrometer at a spectral resolution of 3300. Our analysis, which utilizes a model template spectrum, achieves sufficient precision to expect detection of the spectral structure predicted by an irradiated, low-opacity (cloudless), low-albedo, thermochemical equilibrium model for the exoplanet atmosphere. However, our observations show no evidence for the presence of this spectrum ...

2003-01-01

358

Copper and brass aged at open circuit potential in slightly alkaline solutions  

Energy Technology Data Exchange (ETDEWEB)

Surface oxide films were grown on 99.99% copper and brass (copper-zinc alloy, Cu77Zn21Al2) in 0.1 mol L{sup -1} borax solution at open circuit potential and were characterized using various experimental techniques. The composition of the passive films formed in situ on the different materials was studied using differential reflectance spectroscopy. The thickness of the oxide layers on copper and brass was compared by chronopotentiometric curves and potentiodynamic reductions. The electrical properties of each oxide were analyzed by means of electrochemical impedance spectroscopy. Their influence on the oxygen reduction reaction was also investigated using voltammetry hydrodynamic tools such as the rotating disk electrode. The results show that the incorporation of Zn to Cu in brass changes the composition and the thickness of the surface film. The films grown on brass tend to be thicker but less resistive and Zn compounds incorporate to the ...

2009-12-01

359

Consolidated silica glass from nanoparticles  

International Nuclear Information System (INIS)

A dense silica glass was prepared by consolidating a highly dispersed silicic acid powder (particle size 1H magic-angle spinning (MAS) NMR confirmed an increase in hydroxyl groups in the sample prepared by SPS relative to that of the conventional SiO2 reference glass. Aside from the comparably high water content, we conclude from the similarity of the IR-reflectance and the 29Si MAS NMR spectra of the SPS sample and the corresponding spectra of the conventionally prepared silica glass, that the short- and medium-range order is virtually the same in both materials. Raman spectroscopy, however, suggests that the number of three- and four-membered rings is significantly smaller in the SPS sample compared to the conventionally prepared sample. Based on these results we conclude that it is possible to prepare glasses by compacting amorphous powders by the SPS process. The SPS process may therefore enable the preparation of glasses with compositions inaccessible by ...

2008-09-01

360

Comparison between NIR, MIR, concatenated NIR and MIR analysis and hierarchical PLS model. Application to virgin olive oil analysis.  

Science.gov (United States)

This work investigates the potential use of simultaneously near-infrared (NIR) and mid-infrared (MIR) spectroscopies for the quantitative analysis of fatty acids and triacylglycerols and for identifying the Registered Designation of Origin (RDO) of extra virgin olive oils. The two spectral ranges were used separately using PLS and PLS-DA regressions. To combine both information, concatenated matrix was used at the first time, multiblock method using H-PLS models were constructed at the second time. The models were compared in terms of prediction errors. The results obtained with MIR spectroscopy are better than the ones obtained with NIR spectroscopy. The H-PLS methodology seems to be very interesting for quantitative analysis with the use of additional information in the NIR range, which is not present in the MIR one. For RDO identification by discriminant analysis, the use of multiblock method was less efficient. ...

2010-03-29

361

Atomic spectroscopy study of nuclear properties of francium and cesium isotopes; Etude par spectroscopie atomique de proprietes nucleaires d'isotopes de francium et de cesium  

Energy Technology Data Exchange (ETDEWEB)

This work is based on the study of cesium ({sup 118,146}Cs) and francium ({sup 207-213}Fr,{sup 220-228}Fr) isotopes by hyperfine atomic spectroscopy and on the interpretation of these results from the nuclear physics point of view. The measured nuclear quantities are: the spin, the magnetic moment, the electric quadrupole moment and the mean square charge radius. The experimental method which is based on hyperfine optical pumping with a tunable laser, followed by magnetic analysis of the atoms is described in the first part. Results related to atomic physics are also presented. In the second part, these data are interpreted in the framework of nuclear models. The deformation of light cesium isomers are compared to values obtained from a theoretical self-consistent calculation. Heavy francium isotopes are situated in an area where the existence of static octupole deformations have been predicted. The odd-even staggering measured on the mean square radius is abnormal ...

1986-04-15

362

Direct Comparison of the X-Ray Emission and Absorption of Cerium Oxide  

Energy Technology Data Exchange (ETDEWEB)

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

2010-11-24

363

Zeolite-supported catalysts. Report for August 1986-November 1987  

Energy Technology Data Exchange (ETDEWEB)

The present paper is a comparative study of the cerium-containing nickel catalysts supported on x- and y-zeolites. In general, the addition of cerium ions caused an increase in the catalytic activity for CO hydrogenation and shifted the product selectivity to high molecular weight hydrocarbons. The degree of the effect of cerium additive depends on the ratio of cerium to nickel contents, the reduction temperature, and the nature of the supporting materials. Catalyst characterization, including volumetric hydrogen chemisorption, temperature programmed reduction/desorption, x-ray diffraction, surface area measurements, in-situ infrared spectroscopy and x-ray photoelectron spectroscopy, was performed in order to interpret the phenomena due to the effects of cerium additives and the support effect on Ni/zeolite catalysts.

1988-01-01

364

Visible light photocatalytic activity and Photoelectrochemical property of Fe-doped TiO2 hollow spheres by sol?gel method  

British Library Electronic Table of Contents (United Kingdom)

Fe-doped TiO2 hollow spheres (Fe-THs) were synthesized by sol?gel process using carbon spheres as templates. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV?vis diffuse reflectance spectrum (DRS), N2 adsorption?desorption isotherms, Electron paramagnetic resonance (EPR) spectroscopy and Photoluminescence emission spectroscopy (PL). UV?vis spectra showed that Fe3+ doping could extend the absorption edge to the visible region. EPR spectra showed that Fe3+ was incorporated into the crystal lattice of TiO2, which could inhibit the recombination of photo-induced electron?hole pairs and improve the photocatalytic activity. The photocatalytic activities of the prepared samples were evaluated for the degradation of dye Reactive Brillia...

2011-01-01

365

Unilateral NMR, 13C CPMAS NMR spectroscopy and micro-analytical techniques for studying the materials and state of conservation of an ancient Egyptian wooden sarcophagus  

British Library Electronic Table of Contents (United Kingdom)

A multi-technique approach was employed to study a decorated Egyptian wooden sarcophagus (XXV?XXVI dynasty, Third Intermediate Period), belonging to the Museo del Vicino Oriente of the Sapienza University of Rome. Portable non-invasive unilateral NMR was applied to evaluate the conservation state of the sarcophagus. Moreover, using unilateral NMR, a non-invasive analytical protocol was established to detect the presence of organic substances on the surface and/or embedded in the wooden matrix. This protocol allowed for an educated sampling campaign aimed at further investigating the state of degradation of the wood and the presence of organic substances by 13C cross polarization magic angle spinning (CPMAS) NMR spectroscopy. The composition of the painted layer was analysed by optical micr...

2011-01-01

366

Tunable erbium-doped fiber ring laser for applications of infrared absorption spectroscopy  

British Library Electronic Table of Contents (United Kingdom)

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

2007-01-01

367

Terahertz time-domain spectroscopy of atmospheric water vapor from 0.4 to 2.7 THz.  

Energy Technology Data Exchange (ETDEWEB)

We conducted broadband absorption measurements of atmospheric water vapor in the ground state, X {sup 1}A{sub 1} (000), from 0.4 to 2.7 THz with a pressure broadening-limited resolution of 6.2 GHz using pulsed, terahertz time-domain spectroscopy (THz-TDS). We measured a total of seventy-two absorption lines and forty-nine lines were identified as H{sub 2}{sup 16}O resonances. All the H{sub 2}{sup 16}O lines identified were confirmed by comparing their center frequencies to experimental values available in the literature.

2005-10-01

368

Study of surface segregation of Si on palladium silicide using Auger electron spectroscopy  

International Nuclear Information System (INIS)

The transformation of Pd/Si to Pd_2Si/Si is studied using Auger electron spectroscopy over a wide temperature range of 370-1020 K. The Pd film gets totally converted to Pd_2Si upon annealing at 520 K, and beyond 570 K, Si starts segregating on the surface of silicide. It is found that the presence of surface oxygen influences the segregation of Si. The time evolution study of Si segregation reveals that segregation kinetics is very fast and the segregated Si concentration increases as the temperature is increased. Scanning electron microscopy measurements show that Pd_2Si is formed in the form of islands, which grow as the annealing temperature is increased.

2004-11-21

369

Study of some Ayurvedic Indian medicinal plants for the essential trace elemental contents by instrumental neutron activation analysis and atomic absorption spectroscopy techniques  

Energy Technology Data Exchange (ETDEWEB)

Elemental analysis of some medicinal plants used in the Indian Ayurvedic system was performed by employing instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS) techniques. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activity was counted by gamma ray spectrometry using an efficiency calibrated high resolution high purity germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the elements under study. The variation in elemental concentration in same medicinal plants samples collected in summer, winter and rainy seasons was studied and the biological effects of these elements on human beings are discussed. (orig.)

2009-07-01

370

Structural characterization of liposomes made of diether archaeal lipids and dipalmitoyl-L-a-phosphatidylcholine  

British Library Electronic Table of Contents (United Kingdom)

The physicochemical properties of binary lipid mixtures of diether C25,25 lipids and dipalmitoyl-L-a-phosphatidylcholine (DPPC) were studied using photon correlation, fluorescence and electron paramagnetic resonance spectroscopy, and transmission electron microscopy. These two types of lipids can be mixed at all molar ratios to form unilamellar and multilamellar liposomes. Fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatrien in mixed liposomes indicates that the abrupt changes in order parameter in the hydrophobic part of bilayer membranes made of DPPC lipids disappears with increasing mol%C25,25 lipids. Electron paramagnetic resonance spectroscopy shows that at temperatures below 50^oC, the interfacial regions of membrane bilayer of mixed liposomes is more fluid than for pure DPPC lipo...

2011-01-01

371

Spectroscopy of gadolinium gallium garnet crystals doped with Y b3+ revisited  

International Nuclear Information System (INIS)

The optical spectroscopy measurements of gadolinium gallium garnet (GGG) crystals doped with Yb show evidence of the presence of non-equivalent optical centers with very similar radiative decay rates. The energy level schemes of those centers have been determined on the basis of optical absorption, luminescence and Raman experiments. Crystal field fitting resulted in two sets of slightly different crystal field parameters for two non-equivalent Yb centers. Both sets of parameters describe perfectly the experimentally detected Y b3+ energy levels. Correlation between systematic trends in the experimental energy level schemes and crystal field parameters is discussed.

2010-06-30

372

Spatial distribution of arsenic and heavy metals in willow roots from a contaminated floodplain soil measured by X-ray fluorescence spectroscopy  

British Library Electronic Table of Contents (United Kingdom)

Under changing redox conditions some plants create plaques at their root surface, which may affect the mobility and uptake of As and heavy metals but it is unknown to what extent this also holds true for willows in contaminated floodplain soils. Therefore, willow roots were sampled from a phytoremediation trial in the contaminated floodplain of the river Elbe (Germany), cryofixed, freeze-dried, and cross sections were mapped for the distribution of As, Ca, Cu, Fe, K, Mn, Ni, S and Zn by synchrotron based X-ray fluorescence spectroscopy. The elements Ca, Cu, Ni, S and Zn were concentrated in the aerenchymatic tissue, and not associated with Fe and Mn. Mixed Fe-Mn plaques covered the surface of the willow roots and As was accumulated in these plaques. The observed association pattern between...

2011-01-01

373

Observation of the microstructural changes in lithium titanate by multi-ion irradiation  

Energy Technology Data Exchange (ETDEWEB)

The irradiation behavior of Li{sub 2}TiO{sub 3} under a fusion reactor environment was simulated by simultaneous irradiation of Li{sub 2}TiO{sub 3} by the triple ion beams and the respective single ion beams of O{sup 2+}, He{sup +} and H{sup +}. The microstructural changes in Li{sub 2}TiO{sub 3} caused by the irradiation were measured by Raman spectroscopy and FT-IR photoacoustic spectroscopy. The results suggest that the formation of TiO{sub 2} due to displacements by irradiation occurs, and the irradiation defects generated by irradiation trap hydrogen and increase the amount of hydroxyl near the surface. Such phenomena are believed to significantly affect the chemical form of the released tritium and the tritium inventory in the breeding materials of a fusion reactor.

2004-08-01

374

Observation of the microstructural changes in lithium titanate by multi-ion irradiation  

International Nuclear Information System (INIS)

The irradiation behavior of Li_2TiO_3 under a fusion reactor environment was simulated by simultaneous irradiation of Li_2TiO_3 by the triple ion beams and the respective single ion beams of O"2"+, He"+ and H"+. The microstructural changes in Li_2TiO_3 caused by the irradiation were measured by Raman spectroscopy and FT-IR photoacoustic spectroscopy. The results suggest that the formation of TiO_2 due to displacements by irradiation occurs, and the irradiation defects generated by irradiation trap hydrogen and increase the amount of hydroxyl near the surface. Such phenomena are believed to significantly affect the chemical form of the released tritium and the tritium inventory in the breeding materials of a fusion reactor.

2004-08-01

375

Nuclear Charge Radius of Lithium-11  

Energy Technology Data Exchange (ETDEWEB)

We have determined the nuclear charge radius of 11Li by high-precision laser spectroscopy. The experiment was performed at the TRIUMF-ISAC facility where the 7Li-11Li isotope shift was measured in the 2s to 3s electronic transition using Doppler-free two-photon spectroscopy with a relative accuracy better than 10 5. The accuracy reached in previous experiments on the other lithium isotopes was improved. Most of the isotope shifts measured in the experiment are due to difference in the mass of the nuclei but small contributions are produced by the change in proton distribution, QED and relativistic effects have to be taken into account as well. By comparing the experimental results with sophisticated atomic calculations of the mass dependent effect the nuclear charge radii of the lithium isotopes are found to decrease monotonically from 6Li to 9Li while the nuclear charge radius of 11Li is about 11% larger than that of 9Li.

2006-07-01

376

Lowering the activation temperature of TiZrV non-evaporable getter films [for LHC  

CERN Document Server

In order to reduce the activation temperature of the TiZrV alloy, thin films of various compositions were produced by three-cathode magnetron sputtering on stainless-steel substrates. For the characterisation of the activation behaviour the surface chemical composition has been monitored by Auger electron spectroscopy during specific in situ thermal cycles. The volume elemental composition of the film has been measured by energy dispersive X-ray spectroscopy and the morphology (crystal structure and size of the crystallites) has been investigated by X-ray diffraction. The criteria indicating the sample quality and its dependence on film structure and chemical composition are presented and discussed. (13 refs).

2001-01-01

377

Interaction of insulin with a triblock copolymer of PEG-(fumaric-sebacic acids)-PEG: Thermodynamic and spectroscopic studies  

British Library Electronic Table of Contents (United Kingdom)

A comparative study on the interaction of (PEG-co-P(FA/SC)-co-PEG) triblock copolymer with bovine and human insulins was carried out using isothermal titration calorimetry (ITC), circular dichroism (CD), and fluorescence spectroscopy. ITC data show that the copolymer has a low affinity for both proteins, with an association constant of about 7?9?103?M ?1. Results also show that binding is enthalpically driven, and disfavored by conformational entropy. CD spectroscopy studies reveal a small increase in the helical content and a decrease in ?-structure as well as random coil in both proteins. Acrylamide quenching experiments display reduced accessibility of tyrosines, while intrinsic fluorescence spectra show lower tyrosine emission. Furthermore, thermal unfolding experiments, studied by far...

2007-01-01

378

Infrared spectroscopy of rovibrational transitions of methyl radicals (CH3, CD3) in solid parahydrogen  

British Library Electronic Table of Contents (United Kingdom)

The n3 and n4 vibrational transitions of CH3 and CD3 isolated in solid parahydrogen were studied by high-resolution infrared spectroscopy. The radicals were produced by in situ UV photolysis of methyl iodides trapped in solid parahydrogen. The observed spectra showed clear rotational fine structures, which were subjected to further splitting due to the electrostatic field of solid parahydrogen. The molecular constants and crystal field parameters of the radicals in solid parahydrogen were determined by analyzing the spectral structures of the n3 and n4 transitions of CD3 by the crystal field theory. The rotational constants of the CD3 radical were found to be only a few percent smaller than those in the gas phase. The determined crystal field parameters indicated significant quantum effect...

2011-01-01

379

Influence of intracavity doppler frequency shift in the swept-cavity ringdown spectroscopy incorporating continuous-wave laser excitation  

International Nuclear Information System (INIS)

Cavity ringdown spectroscopy (CRDS) with continuous-wave (cw) laser excitation has added high frequency resolution to the ability of CRDS being used for the absolute quantification of trace-level species present in many chemical processes. Cavity dithering technique has easily resolved the problem of resonant coupling of a cw laser light into a high-finesse cavity. The present study addresses the potential uncertainty involved in such cw-CRDS techniques incorporating the cavity mirror motion, i.e., the doppler frequency shift of a probe light inside the cavity. In the high-resolution spectroscopic work of megahertz-accuracy, even the influence of intracavity doppler effect may become significant.

2001-11-01

380

In situ Raman spectroscopy investigation of bioactive glass reactivity: Simulated body fluid solution vs TRIS-buffered solution  

British Library Electronic Table of Contents (United Kingdom)

In the present contribution, the innovative in situ Raman micro-spectroscopy was applied to investigate the in vitro reactivity of various bioactive glasses. All the investigated glasses belonged to the Na2O\\K2O-CaO-P2O5-SiO2 system, but contained sensibly different percentages of network modifiers. The glasses were immersed for increasing times, up to 96h, in simulated body fluid (SBF) and in tris-buffered (TRIS) solution. In this way, two fundamental items were addressed, i.e. the effect of the glass composition and the nature of the soaking fluid on the overall reactivity. As regards the SBF, all the glasses were able to promote the formation of a hydroxyl-carbonate apatite (HCA) surface layer in very short times. The reaction rate was particularly quick for the 45S5 Bioglass and for it...

2011-01-01

381

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

Energy Technology Data Exchange (ETDEWEB)

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

1995-01-01

382

Gauging film thickness: A comparison of an x-ray diffraction technique with Rutherford backscattering spectrometry  

Energy Technology Data Exchange (ETDEWEB)

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

1985-01-15

383

Fullerene-Derivatized Amino Acids: Synthesis, Characterization, Antioxidant Properties, and Solid-Phase Peptide Synthesis  

British Library Electronic Table of Contents (United Kingdom)

A series of [60]fullerene-substituted phenylalanine (Baa) and lysine derivatives have been prepared by the condensation of 1,2-(4prime-oxocyclohexano)fullerene with the appropriately protected (4-amino)phenylalanine and lysine, respectively. Conversion of the imine to the corresponding amine is achieved by di-acid catalyzed hydroboration. The reduction of the imine is not accompanied by hydroboration of the fullerene cage. The [70]fullerene phenylalanine derivative has also been prepared as have the di-amino acid derivatives. The compounds were characterized by MALDI-TOF mass spectrometry, UV/Vis spectroscopy, and cyclic voltammetry. 1H and 13C NMR spectroscopy allowed the observation of diastereomers. Fullerene-substituted peptides may be synthesized on relatively large scale by solid-pha...

2007-01-01

384

Electrochemical performance of flowerlike CaSnO{sub 3} as high capacity anode material for lithium-ion batteries  

Energy Technology Data Exchange (ETDEWEB)

Nanosized CaSnO{sub 3} is synthesized by a hydrothermal process and characterized by X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM). The SEM observation shows the sample has a porous flowerlike morphology. The electrochemical results exhibit that the stable and reversible capacity of 547 mAh g{sup -1} is obtained after 50 cycles at 60 mA g{sup -1} (0.1 C) and the corresponding charge capacity is determined to be 316 mAh g{sup -1} at the current density of 2.5 C. Cyclic voltammetry and electrochemical impedance spectroscopy data are analyzed to complement the galvanostatic results. The observed excellent performance is attributed to the porous structure and large surface area of flowerlike CaSnO{sub 3}.

2010-04-30

385

Effect of tungsten on the corrosion behavior of sulfuric acid-resistant steels for flue gas desulfurization system  

British Library Electronic Table of Contents (United Kingdom)

Flue gas desulfurization systems (FGDs) are operated in severely corrosive environments that cause sulfuric acid dew-point corrosion. The corrosion behavior of low-alloy steels was tested using electrochemical techniques (electrochemical impedance spectroscopy, potentiodynamic tests, potentiostatic tests), and the corrosion products were analyzed by scanning electron microscopy and X-ray photoelectron spectroscopy. The electrochemical results showed that alloying W with small amounts of Sb, Cu, and Co improves the corrosion resistance of steels. The results of surface analyses showed that the surface of the steels alloyed with W consisted of W oxides and higher amounts of Sb and Cu oxides. This suggests that the addition of W promotes the formation of a protective WO3 film, in addition to ...

2011-01-01

386

Effect of different treatments on acid centers of very high silicon zeolites studied by ir spectroscopy  

Science.gov (United States)

Using the infrared spectroscopy method, we have studied the effect of thermal dehydration (under vacuum and in air) and treatment with water vapor on the acid centers of very high silicon zeolites of the ZSM type. We have shown that dehydration under vacuum and in air completely and irreversibly removes the OH groups at 1120/sup 0/K, while treatment with water vapor removes these groups at 770/sup 0/K. The Lewis acid centers of dehydrated zeolites (represented by two types of centers) are more heat-stable than the Bronsted acid centers, but the vapor treatment at 1020/sup 0/K leads to the disappearance of the Lewis acid centers. In this work, we discuss the reasons for destruction of the acid centers of the zeolites under different treatment conditions.

1986-08-01

387

Effect of Mo on the composition and electronic properties of the passive films formed on stainless steels at 350 C  

Energy Technology Data Exchange (ETDEWEB)

The effect of Mo addition as an alloying element to stainless steel alloys is investigated by capacitance (Mott Schottky approach), and photoelectrochemistry measurements. Complementary studies were made using Auger electron spectroscopy and X-ray photoelectron spectroscopy. The Mott-Schottky approach and the photoelectrochemical studies showed that the presence of Mo as an alloying element affects the semiconductive properties of the oxide films. The analytical results have shown that the oxide films formed on stainless steels are composed by an external Fe rich region and an inner Cr rich region. No significant amount of Mo was found in the outer layers of the film. The presence of Mo leads to an increase of the chromium content in the inner layers of the film, although without increasing the film thickness. (orig.) 30 refs.

1998-12-31

388

Effect of Mo on the composition and electronic properties of the passive films formed on stainless steels at 350 C  

International Nuclear Information System (INIS)

The effect of Mo addition as an alloying element to stainless steel alloys is investigated by capacitance (Mott Schottky approach), and photoelectrochemistry measurements. Complementary studies were made using Auger electron spectroscopy and X-ray photoelectron spectroscopy. The Mott-Schottky approach and the photoelectrochemical studies showed that the presence of Mo as an alloying element affects the semiconductive properties of the oxide films. The analytical results have shown that the oxide films formed on stainless steels are composed by an external Fe rich region and an inner Cr rich region. No significant amount of Mo was found in the outer layers of the film. The presence of Mo leads to an increase of the chromium content in the inner layers of the film, although without increasing the film thickness. (orig.)

1997-08-25

389

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

British Library Electronic Table of Contents (United Kingdom)

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

2011-01-01

390

Chemical composition of passive films on AISI 304 stainless steel  

Energy Technology Data Exchange (ETDEWEB)

Chemical characterization of passive films formed on AISI 304 austenitic stainless steel, in a borate/boric acid solution at pH 9.2, under various conditions of potential, temperature, and polarizations time, was made by Auger electron spectroscopy combined with ion sputtering, and x-ray photoelectron spectroscopy (XPS). The depth chemical composition, thickness, and duplex character of the passive layers were determined after processing AES sputter profiles by their quantitative approach based on the sequential layer sputtering model. Moreover, separated contributions of elements in their oxidized and unoxidized state could be disclosed from part to part of the oxide-alloy interface. The XPS study specified the chemical bondings which take placed inside the film, between Fe and oxygen (and water).

1994-12-01

391

Characterizations of passive films formed on stainless steel in high temperature water  

International Nuclear Information System (INIS)

Surface study techniques were used to investigate films on Type 304 stainless steel which were formed during exposure to high purity water at 288"0C. The results indicated that the film chemistry depended strongly upon the concentration of the dissolved O_2 in the water. Films formed in water having 8 ppm O_2 were stoichiometric mixed oxides; whereas those formed in water with 10 ppb O_2 were highly defective oxyhydroxides. The latter films are not as protective as the stoichiometric oxides. Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS) were used to investigate the films. (Auth.).

1983-06-03

392

Cavity ringdown spectroscopy with a continuous-wave laser: calculation of coupling efficiency and a new spectrometer design.  

Science.gov (United States)

For the efficient operation of a cavity ringdown spectroscopy (CRDS) system utilized with a continuous-wave (cw) laser, we numerically analyze the coupling efficiency of a cw laser to a ringdown cavity in terms of changes in the scanning rate, the laser linewidth, and the mirror reflectivity. We also demonstrate a new simple design for a CRDS system that can produce a CRDS signal with only a piezoelectric transducer (PZT), without the acousto-optic modulator that is usually adopted to switch off the cw laser beam that enters the cavity. Furthermore, we investigate the feasibility of the cw CRDS technique with a fast-scanning PZT by recording a CRDS spectrum of acetylene overtones. The detection sensitivity that corresponds to the noise-equivalent absorption is found to be approximately 3 x 10(-9)/cm. PMID:18305817

1999-03-20

393

Breathers in Josephson junction ladders: Resonances and electromagnetic wave spectroscopy  

DEFF Research Database (Denmark)

We present a theoretical study of the resonant interaction between dynamical localized states (discrete breathers) and linear electromagnetic excitations (EE's) in Josephson junction ladders. By making use of direct numerical simulations we find that such an interaction manifests itself by resonant steps and various sharp switchings (voltage jumps) in the current-voltage characteristics. Moreover, the power of ac oscillations away from the breather center (the breather tail) displays singularities as the externally applied dc bias decreases. All these features may be mapped to the spectrum of EE's that has been derived analytically and numerically. Using an improved analysis of the breather tail, a spectroscopy of the EE's is developed, The nature of breather instability driven by localized EE's is established.

2001-01-01

394

Bragg curve spectroscopy of fission fragments by using parallel plate avalanche counters  

Energy Technology Data Exchange (ETDEWEB)

By using a charge-sensitive preamplifier and methods of energy spectroscopy we investigated the response of a parallel plate avalanche counter in order to scan the Bragg curve. The detector was operated in butane, pentane and heptane which also served as stopping gases. In this paper, we report on results obtained with fission fragments from a /sup 252/Cf source. We achieved a separation of the light and heavy fragment groups in the interval of gas absorber thickness from about 500 ..mu..g cm/sup 2/ to 1.5 mg cm/sup 2/. The best energy loss resolution was achieved with pentane at E/papprox.=70 V cm/sup 1/ Torr/sup 1/ resulting in delta..delta..E/..delta..Eapprox.=13%. The corresponding shape of the ..delta..E spectrum reproduces correctly the nuclear charge distribution of the fragments. (orig.).

1985-07-01

395

Bragg Curve Spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

An alternative utilization is presented for the gaseous ionization chamber in the detection of energetic heavy ions, which is called Bragg Curve Spectroscopy (BCS). Conceptually, BCS involves using the maximum data available from the Bragg curve of the stopping heavy ion (HI) for purposes of identifying the particle and measuring its energy. A detector has been designed that measures the Bragg curve with high precision. From the Bragg curve the range from the length of the track, the total energy from the integral of the specific ionization over the track, the dE/dx from the specific ionization at the beginning of the track, and the Bragg peak from the maximum of the specific ionization of the HI are determined. This last signal measures the atomic number, Z, of the HI unambiguously.

1981-05-01

396

Boron transient enhanced diffusion in heavily phosphorus doped silicon  

International Nuclear Information System (INIS)

A study has been made of B transient enhanced diffusion (TED) in heavily P-doped Si using secondary ion mass spectroscopy (SIMS) and positron annihilation spectroscopy (PAS). The P-doped silicon was implanted with boron ions of 40 keV energy to a dose of 3 x 10"1"4 cm"-"2, and then annealed at temperatures ranging from 700--1,000 C in a N_2 ambient for varying durations. As P doping concentration increased from 3 x 10"1"9 to 1 x 10"2"0 cm"-"3, boron diffusivity and the immobile boron fraction decreased. The experimental results are inconsistent with the predictions of the Fermi-level model and suggest that the clustering between B atoms and Si interstitials should be invoked in order to explain the immobile portion of the B peak during TED.

1996-12-02

397

Biological effects and physical safety aspects of NMR imaging and in vivo spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

An assessment is made of the biological effects and physical hazards of static and time-varying fields associated with the NMR devices that are being used for clinical imaging and in vivo spectroscopy. A summary is given of the current state of knowledge concerning the mechanisms of interaction and the bioeffects of these fields. Additional topics that are discussed include: (1) physical effects on pacemakers and metallic implants such as aneurysm clips, (2) human health studies related to the effects of exposure to nonionizing electromagnetic radiation, and (3) extant guidelines for limiting exposure of patients and medical personnel to the fields produced by NMR devices. On the basis of information available at the present time, it is concluded that the fields associated with the current generation of NMR devices do not pose a significant health risk in themselves. However, rigorous guidelines must be followed to avoid the physical interaction of these fields ...

1985-08-01

398

Banana peel extract mediated novel route for the synthesis of palladium nanoparticles  

British Library Electronic Table of Contents (United Kingdom)

Bio-inspired palladium nanoparticles were synthesized by using banana peel extract (BPE), a non-toxic eco-friendly material. Boiled, crushed, acetone precipitated, air-dried peel powder was used to reduce palladium chloride. The palladium nanoparticles were characterized by using UV-Visible spectroscopy, scanning electron microscope-energy dispersive spectra (SEM-EDS) and X-ray diffraction (XRD) analysis. Dynamic light scattering (DLS) studies revealed the average size of nanoparticles to be 50nm. Fourier transform infra red spectroscopy (FTIR) implicated the role of carboxyl, amine and hydroxyl groups in the synthetic process. This paper thus describes a novel green method for the synthesis of palladium nanoparticles.

2010-01-01

399

Auger electron spectroscopy studies of GaAs and Si metal-semiconductor structures  

Science.gov (United States)

The use of Auger electron spectroscopy (AES) combined with in situ sputter etching for revealing the metallurgy of the metal-semiconductor interface is presented. The physical basis, measurement techniques, and data interpretation for Auger analysis of thin-film structures are briefly reviewed. Results of a detailed study of an alloyed multilayered contact (Ni/Au-Ge) on n-type epitaxial GaAs are summarized to illustrate how electrical and metallurgical contact properties can be correlated using AES. In addition, the results of a study of the growth kinetics and chemical phase identification of palladium silicide on single-crystal Si is given, as well as the initial results of a study of aluminum-palladium silicide interaction at elevated temperature. (auth)

1975-01-01

400

Auger electron spectroscopy studies of GaAs and Si metal-semiconductor structures  

International Nuclear Information System (INIS)

The use of Auger electron spectroscopy (AES) combined with in situ sputter etching for revealing the metallurgy of the metal-semiconductor interface is presented. The physical basis, measurement techniques, and data interpretation for Auger analysis of thin-film structures are briefly reviewed. Results of a detailed study of an alloyed multilayered contact (Ni/Au-Ge) on n-type epitaxial GaAs are summarized to illustrate how electrical and metallurgical contact properties can be correlated using AES. In addition, the results of a study of the growth kinetics and chemical phase identification of palladium silicide on single-crystal Si is given, as well as the initial results of a study of aluminum-palladium silicide interaction at elevated temperature.

401

Asymmetric Hydrogenation with Highly Active IndolPhos-Rh Catalysts: Kinetics and Reaction Mechanism  

British Library Electronic Table of Contents (United Kingdom)

The mechanism of the IndolPhos-Rh-catalyzed asymmetric hydrogenation of prochiral olefins has been investigated by means of X-ray crystal structure determination, kinetic measurements, high-pressure NMR spectroscopy, and DFT calculations. The mechanistic study indicates that the reaction follows an unsaturate/dihydride mechanism according to Michaelis-Menten kinetics. A large value of KM (KM=5.01+-0.16 M) is obtained, which indicates that the Rh-solvate complex is the catalyst resting state, which has been observed by high-pressure NMR spectroscopy. DFT calculations on the substrate-catalyst complexes, which are undetectable by experimental means, suggest that the major substrate-catalyst complex leads to the product. Such a mechanism is in accordance with previous studies on the mechanism...

2010-01-01

402

A method to study heavy ion reactions using position sensitive and Bragg curve spectroscopy detectors  

Energy Technology Data Exchange (ETDEWEB)

A large area Bragg curve spectroscopy (BCS) detector and a position sensitive parallel grid avalanche counter have been developed to study heavy ion reactions, such as inelastic excitations and few nucleon transfer reactions near the Coulomb barrier. Reasonably good resolutions have been achieved for energy, atomic number and angle. A theoretical investigation on the mass dependence of the Bragg peak signal from the BCS detector, shows that there is a negligible mass dependence related to the geometry of the detector. The mass number of the heavy ions which cannot be obtained by the above method, has been identified by detecting the corresponding characteristic gamma rays from the product nuclei with two large solid angle gamma ray detectors. (orig.)

1993-10-15

403

A method to study heavy ion reactions using position sensitive and Bragg curve spectroscopy detectors  

International Nuclear Information System (INIS)

A large area Bragg curve spectroscopy (BCS) detector and a position sensitive parallel grid avalanche counter have been developed to study heavy ion reactions, such as inelastic excitations and few nucleon transfer reactions near the Coulomb barrier. Reasonably good resolutions have been achieved for energy, atomic number and angle. A theoretical investigation on the mass dependence of the Bragg peak signal from the BCS detector, shows that there is a negligible mass dependence related to the geometry of the detector. The mass number of the heavy ions which cannot be obtained by the above method, has been identified by detecting the corresponding characteristic gamma rays from the product nuclei with two large solid angle gamma ray detectors. (orig.).

404

The RooStats Project  

CERN Document Server

RooStats is a project to create advanced statistical tools required for the analysis of LHC data, with emphasis on discoveries, confidence intervals, and combined measurements. The idea is to provide the major statistical techniques as a set of C++ classes with coherent interfaces, which can be used on arbitrary model and datasets in a common way. The classes are built on top of RooFit, which provides a very convenient functionality for modeling the probability density functions or the likelihood functions, required as inputs for any statistical technique. Furthermore, RooFit provides the functionality for easily creating models, for analysis combination and for digital publication of the likelihood function and the data. We will present in detail the design and the implementation of the different statistical methods of RooStats. These include various classes for interval estimation ...

2010-01-01

405

Partition Functions of Normal Factor Graphs  

CERN Document Server

One of the most common types of functions in mathematics, physics, and engineering is a sum of products, sometimes called a partition function. After "normalization," a sum of products has a natural graphical representation, called a normal factor graph (NFG), in which vertices represent factors, edges represent internal variables, and half-edges represent the external variables of the partition function. In physics, so-called trace diagrams share similar features. We believe that the conceptual framework of representing sums of products as partition functions of NFGs is an important and intuitive paradigm that, surprisingly, does not seem to have been introduced explicitly in the previous factor graph literature. Of particular interest are NFG modifications that leave the partition function invariant. A simple subclass of such NFG modifications offers a unifying view of the Fourier ...

2011-01-01

406

On parameter derivatives of the associated Legendre function of the first kind (with applications to the construction of the associated Legendre function of the second kind of integer degree and order)  

British Library Electronic Table of Contents (United Kingdom)

A relationship between partial derivatives of the associated Legendre function of the first kind with respect to its degree, Formula Not Shown , and to its order, Formula Not Shown , is established for Formula Not Shown . This relationship is used to deduce four new closed-form representations of Formula Not Shown from those found recently for Formula Not Shown by the author [R. Szmytkowski, On the derivative of the associated Legendre function of the first kind of integer degree with respect to its order (with applications to the construction of the associated Legendre function of the second kind of integer degree and order), J. Math. Chem. 46 (2009) 231]. Several new expressions for the associated Legendre function of the second kind of integer degree and order, Formula Not Shown , suita...

2012-01-01

407

Effects of Behet's Disease on Sexual Function and Psychological Status of Male Patients  

British Library Electronic Table of Contents (United Kingdom)

Abstract Introduction.- There are no studies on the sexual function of male patients with Behet's disease (BD), but it is probable that male sexual dysfunction may be seen in this chronic condition. Aim.- The aim of this study was to assess the effect of BD on male sexual function and psychiatric status, and to examine the relationship between sexual function and depression in this population. Methods.- Patients with a diagnosis of BD for at least one year were included in the study. The patients' age, educational level, and duration of disease were recorded. A healthy control group was selected with highly similar characteristics to the patient group. The sexual functions of the patient and the control groups were assessed using the International Index of Erectile Functions (IIEF), and th...

2011-01-01

408

A lattice gauge theory model for graphene  

CERN Document Server

In this Ph.D. thesis a model for graphene in presence of quantized electromagnetic interactions is introduced. The zero and low temperature properties of the model are studied using rigorous renormalization group methods and lattice Ward identities. In particular, it is shown that, at all orders in renormalized perturbation theory, the Schwinger functions and the response functions decay with interaction dependent anomalous exponents. Regarding the 2-point Schwinger function, the wave function renormalization diverges in the infrared limit, while the effective Fermi velocity flows to the speed of light. Concerning the response functions, those associated to a Kekul\\'e distortion of the honeycomb lattice and to a charge density wave instability are enhanced by the electromagnetic electron-electron interactions (their scaling in real space is depressed), while the lowest order ...

2011-01-01

409

X-ray photoelectron spectroscopy and x-ray excited Auger spectroscopy studies of manganese thiophosphate intercalated with sodium ions  

Science.gov (United States)

Polycrystalline powders of Na{sub 2x}Mn{sub 1-x}PS{sub 3} have been synthesized from layered MnPS{sub 3} material by successive ion-exchange intercalation of potassium and sodium ions. Their x-ray photoelectron spectroscopy (XPS) and x-ray excited Auger spectroscopy spectra have been measured at room temperature using Mg K{alpha} (1253.6 eV) x-ray source. In particular, the Mn, P, and S 2p and Na 1s and 2p core-level regions and the Na Auger KL{sub 23}L{sub 23} transition have been investigated. All the analyzed XPS core-level spectra display a single-peak structure, suggesting the absence of nonequivalent atoms of Na, Mn, P, and S. The manganese XPS spectrum shows, as observed in MnPS{sub 3} and in its cesium and potassium intercalation compounds, typical shake-up satellites, suggesting that the Mn-S bond is yet mainly ionic in nature. The comparison with the XPS spectra relative to MnPS{sub 3} and its potassium intercalation compound (K{sub ...

2008-12-15

410

X-ray and vibrational spectroscopy of manganese complexes relevant to the oxygen-evolving complex of photosynthesis  

Energy Technology Data Exchange (ETDEWEB)

Manganese model complexes, relevant to the oxygen-evolving complex (OEC) in photosynthesis, were studied with Mn K-edge X-ray absorption near-edge spectroscopy (XANES), Mn Kb X-ray emission spectroscopy (XES), and vibrational spectroscopy. A more detailed understanding was obtained of the influence of nuclearity, overall structure, oxidation state, and ligand environment of the Mn atoms on the spectra from these methods. This refined understanding is necessary for improving the interpretation of spectra of the OEC. Mn XANES and Kb XES were used to study a di-(mu)-oxo and a mono-(mu)-oxo di-nuclear Mn compound in the (III,III), (III,IV), and (IV,IV) oxidation states. XANES spectra show energy shifts of 0.8 - 2.2 eV for 1-electron oxidation-state changes and 0.4 - 1.8 eV for ligand-environment changes. The shifts observed for Mn XES spectra were approximately 0.21 eV for oxidation state-changes and only approximately 0.04 eV ...

2001-05-16

411

Valence determination in EuM_2X_2 compounds: L_I_I_I-edge versus Moessbauer isomer shift  

International Nuclear Information System (INIS)

A comparative study by Eu-L_I_I_I X-ray absorption and "1"5"1Eu-Moessbauer spectroscopy is presented for the EuPd_2_-_xAu_x Si_2 series. Possible ways to distinguish between mixed-valent behaviour and final-state effects in the L_I_I_I-edge spectra are discussed.

1986-07-07

412

Valence determination in EuM/sub 2/X/sub 2/ compounds: L/sub III/-edge versus Moessbauer isomer shift  

Energy Technology Data Exchange (ETDEWEB)

A comparative study by Eu-L/sub III/ X-ray absorption and /sup 151/Eu-Moessbauer spectroscopy is presented for the EuPd/sub 2-x/Au/sub x/ Si/sub 2/ series. Possible ways to distinguish between mixed-valent behaviour and final-state effects in the L/sub II /I-edge spectra are discussed.

1986-12-01

413

The triaxial motion in Mo isotopes  

Energy Technology Data Exchange (ETDEWEB)

The nuclear shapes of transitional Mo isotopes are calculated by means of a model based on the cranking approximation and the Strutinksy method. The recent experimental results of the high-spin spectroscopy and lifetime measurement of [sup 87]Mo are studied in detail and explained by the evolution of the [gamma]-deformation with the quasiparticle configurations. The shape calculations with the modified-harmonic-oscillator potential give a critical neutron number N [>=] 47 for the spherical shape of the Mo isotopes. (orig.)

1993-11-22

414

The triaxial motion in Mo isotopes  

International Nuclear Information System (INIS)

The nuclear shapes of transitional Mo isotopes are calculated by means of a model based on the cranking approximation and the Strutinksy method. The recent experimental results of the high-spin spectroscopy and lifetime measurement of "8"7Mo are studied in detail and explained by the evolution of the #gamma#-deformation with the quasiparticle configurations. The shape calculations with the modified-harmonic-oscillator potential give a critical neutron number N #>=# 47 for the spherical shape of the Mo isotopes. (orig.).

415

The production and destruction of negative ions  

Energy Technology Data Exchange (ETDEWEB)

During the present grant period we have continued our study of the photodetachment of atomic negative ions using cross-beam photoelectron detachment spectroscopy. The experimental technique involves the measurement of, under conditions of good energy and angular resolution, kinetic energies, yields and angular distributions of photoelectrons ejected from the interaction region between perpendicularly crossed laser and negative ion beams. 6 figs.

1990-01-01

416

The nucleus {sup 143}Nd attempt on complete spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The 142Nd and 143Nd nucleus excited states have been studied using the {sup 142,143}Nd(p,p`) and {sup 140}Ce({alpha},n){sup 143}Nd reactions. The energy level schemes were determined as well as spectroscopic information about spin, parity and multipolarity of electromagnetic transitions. 54 refs, 25 figs, 9 tabs.

1991-09-01

417

The nucleus "1"4"3Nd attempt on complete spectroscopy  

International Nuclear Information System (INIS)

The 142Nd and 143Nd nucleus excited states have been studied using the "1"4"2","1"4"3Nd(p,p') and "1"4"0Ce(#alpha#,n)"1"4"3Nd reactions. The energy level schemes were determined as well as spectroscopic information about spin, parity and multipolarity of electromagnetic transitions. 54 refs, 25 figs, 9 tabs.

1991-01-01

418

The content of natural radioactive materials in phosphate fertilizers and their contribution to the radiation exposure of the human population  

International Nuclear Information System (INIS)

The Ra, Th, and K-40 content of the most important phosphate fertilizers used and authorized in the FRG was determined by #gamma#-spectroscopy. The results, together with statistical data on the consumption and use of fertilizers, were used for an estimation of the contribution of #gamma#-radiation from phosphate fertilizers to the external population exposure in the FRG. (orig./AK).

1974-09-23

419

Testing of CFC Targets by Plasma Heat Fluxes Relevant to Elms and Mitigated Disruptions in ITER  

International Nuclear Information System (INIS)

Carbon fibre composite (CFC) was irradiated by hot plasma streams at plasma gun facility MK-200UG. The CFC targets were tested by plasma loads relevant to Edge Localized Modes (ELM) and mitigated disruptions in ITER. Onset condition of CFC evaporation and properties of evaporated carbon were studied by use of infrared pyrometry and visible spectroscopy.

2006-01-01

420

Spectroscopy of Neutron-Rich Nuclei with the CLARA-PRISMA Setup  

International Nuclear Information System (INIS)

The CLARA-PRISMA setup, composed of an array of 25 Clover detectors placed at the target position of the magnetic spectrometer PRISMA, has recently concluded its campaign to study the structure of moderately neutron-rich nuclei. In this contribution, results obtained in the vicinity of the doubly-magic nucleus "4"8Ca are presented, together with results obtained for the heavy iron isotopes. The perspectives offered by the forthcoming operation of the AGATA Demonstrator Array coupled to PRISMA are also discussed. (author)

2009-03-01

421

Spectral characteristics of lignite open cast mining systems: a preliminary status  

Energy Technology Data Exchange (ETDEWEB)

The application of a Compact Airborne Spectrographic Imager to assessment and monitoring of lakes in a lignite open cast mining area in central Germany is described. The imager was used in combination with additional ground experiments, such as field spectroscopy and water sampling. The spectral characteristics of an instrument under development for monitoring geochemical and hydrological processes are presented. Summary form only.

1999-07-01

422

Search for magnetic rotation in {sup 202}Pb and {sup 203}Pb  

Energy Technology Data Exchange (ETDEWEB)

High-spin states in {sup 202}Pb and {sup 203}Pb have been investigated by in-beam {gamma}-ray spectroscopy following the reaction {sup 198}Pt({sup 9}Be,xn). A search for magnetic rotational bands in these isotopes confirmed one of the two bands previously assigned to {sup 202}Pb and revealed a new band in this isotope. No evidence for magnetic rotation has been found in {sup 203}Pb. (orig.)

2000-11-01

423

Release of oxidized plastocyanin from photosystem I limits electron transfer between photosystem I and cytochrome b6f complex in vivo  

UK PubMed Central (United Kingdom)

We used fast absorbance spectroscopy to investigate in vivo binding dynamics and electron transfer between plastocyanin (pc) and photosystem I (PSI), and cytochrome (cyt) f...Full Text Available

2005-05-10

424

Reactivity of aliphatic amines toward platinum(II) complexes  

Energy Technology Data Exchange (ETDEWEB)

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

1994-08-31

425

Radiochemical and Raman spectroscopy study of the nature of adsorbed layers on a silver electrode  

International Nuclear Information System (INIS)

The structure of the layers formed on a silver electrode by the adsorption of pyridine, Cl"-, CN"- and SO_4"2"- is discussed. A comparison of the amount of the species adsorbed with their Raman spectra shows that there is no simple relation between the species concentration and the enhancement of the Raman intensity. Furthermore, the inhomogeneity of the layers is shown by Raman microscopy observations. These results lead the authors to propose the formation of a new species stabilized in the colloidal silver layer. The Raman enhancement could be explained by the existence of a resonance effect. (Auth.).

426

Radioactive and stable isotope geology  

Energy Technology Data Exchange (ETDEWEB)

Aimed at post-graduate and post-doctoral researchers in geochemistry, this book reflects the rapid changes in the applications of radioactive and stable isotope analysis to a range of geological and geochemical problems. Isotropic chemistry and methods used in mass spectroscopy are discussed initially. The second section deals with radiometric dating methods. The role of isotopes in climate and environmental research is also explored. The book closes with a section on extra-terrestrial matter, geothermometry and the isotopic geochemistry of the Earth`s lithosphere. (UK).

1997-10-01

427

Quantitative spectroscopy of close binary stars  

CERN Document Server

The method of spectral disentangling has now created the opportunity for studying the chemical composition in previously inaccessible components of binary and multiple stars. This in turn makes it possible to trace their chemical evolution, a vital aspect in understanding the evolution of stellar systems. We review different ways to reconstruct individual spectra from eclipsing and non-eclipsing systems, and then concentrate on some recent applications to detached binaries with high-mass and intermediate-mass stars, and Algol-type mass-transfer systems.

2011-01-01

428

Pyrolysis of dichlorodithiourea cadmium(II)  

Energy Technology Data Exchange (ETDEWEB)

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

1987-02-20

429

Principal component analysis as a method for silicide investigation with Auger electron spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The possibilities and problems of PCA in phase separation are shown on Ni, Pd, and Pt silicides. The PCA depth profiles are less influenced by sputter and matrix effects than usual Auger depth profiles. The position of the silicide-Si interface is well defined by the component distribution crossover in PCA profiles. An interface component between Pd and Pt silicides and Si substrate is determined by PCA.

1983-10-16

430

Principal component analysis as a method for silicide investigation with Auger electron spectroscopy  

International Nuclear Information System (INIS)

The possibilities and problems of PCA in phase separation are shown on Ni, Pd, and Pt silicides. The PCA depth profiles are less influenced by sputter and matrix effects than usual Auger depth profiles. The position of the silicide-Si interface is well defined by the component distribution crossover in PCA profiles. An interface component between Pd and Pt silicides and Si substrate is determined by PCA. (author).

431

Optical spectroscopy of uranium monochalcogenides and monopnictides  

International Nuclear Information System (INIS)

The optical properties of uranium monochalcogenides and monopnictides are discussed in terms of their electronic structure. A comparison is made with corresponding rare earth compounds. It is shown that there are close similarities to mixed valence CeN. the results support the occurrence of a dip in the density of d states near Esub(F), where the f density of states has its maximum. Empirical energy level schemes are derived which are found to agree with the existing information from XPS measurements and recent theories. (orig.).

1980-12-01

432

ORNL `90  

Energy Technology Data Exchange (ETDEWEB)

This overview of research conducted at ORNL in 1991 presents information on the subjects of biology, physics, and the environment. Specific topics include gene mutations in kidney disease, technology assessments in thermonuclear fusion, submarine hunting technology, ozone-safe refrigerants, optical data storage via surface enhanced raman spectroscopy, and waste mitigating microbes. (GHH)

1990-12-31

433

ORNL '90  

Energy Technology Data Exchange (ETDEWEB)

This overview of research conducted at ORNL in 1991 presents information on the subjects of biology, physics, and the environment. Specific topics include gene mutations in kidney disease, technology assessments in thermonuclear fusion, submarine hunting technology, ozone-safe refrigerants, optical data storage via surface enhanced raman spectroscopy, and waste mitigating microbes. (GHH)

1990-01-01

434

Micro area analysis and measurement of electronic device material (challenge to utmost limits). Characterization of interface elect`ron structure by photon-and electron-spectroscopies; Denshi debaisu yo zairyo no bisho ryoiki bunseki-keisoku (kyokugen eno chosen). Koshi-denshi bunkoho ni yoru kaimen denshi jotai hyoka  

Energy Technology Data Exchange (ETDEWEB)

A method for detecting electrons emitted as secondary particles by photon incidence to a specimen, as well as a method of using the photons emitted by electron incidence as detecting particles are explained. Pd-Si(100)2{times}1 system is adopted for a case study of using photo-electron spectroscopy where synchrotron emitted light in soft X-ray region is used as the incident light. Pd atoms are deposited little by little on clean Si surface to investigate the electron structure of the surface, and the interface electron structure after bonded formation of Pd(thin film)-Si(substrate) is estimated. Radiation soft X-ray spectroscopy is employed to observe the real state of the bonded interface of Pd(thin film)-Si(substrate) prepared by depositing Pd film in a short period of time. In the case of radiation soft X-ray spectroscopy with electron beam excitation, bonded system of thin film and substrate can be investigated by ...

1995-07-20

435

Interactions of myristic acid with bovine serum albumin: a 13C NMR study.  

UK PubMed Central (United Kingdom)

Interactions of myristic acid with bovine serum albumin were studied by 13C NMR spectroscopy at 50.3 MHz using 90% isotopically substituted [1-13C]-, [3-13C]-, and [14-13C]myristic acids, either individually...Full Text Available

1984-06-01

436

Intensity of auger-emission of silicon from binary compounds in the ion auger spectroscopy  

International Nuclear Information System (INIS)

Auger-electron emission from different silicides has been studied for 4 and 10 keV Ar ion excitation. The intensity of the SiLMM Auger line changes significantly with channing concentration and atomic number of the metal-parthner. The experimental results can be explained in terms of a simple model based on the probability of Si-Si collision symmetric cascade in these binary compounds.

437

In-beam conversion electron spectroscopy using the SACRED array  

International Nuclear Information System (INIS)

Conversion electron studies of medium-heavy to heavy nuclear mass systems are important where the internal conversion process begins to dominate over gamma-ray emission. The use of a segmented detector array sensitive to conversion electrons has been used to study multiple conversion electron cascades from nuclear transitions. The application of the silicon array for conversion electron detection (SACRED) for in-beam measurements has successfully been implemented. (orig.). With 2 figs.

438

Gas-temperature-dependent generation of cryoplasma jet under atmospheric pressure  

International Nuclear Information System (INIS)

Plasma with a gas temperature below room temperature is not yet fully understood although it is expected to be an attractive tool for applications to material processing. In the present work, gas-temperature-dependent generation of a cryoplasma jet was studied. So far, we have generated a helium cryoplasma jet (296-5 K) under atmospheric pressure. At gas temperatures below 20 K, the helium excimer, He2, was observed clearly from by optical emission spectroscopy.

2008-09-08

439

Frequency evaluation of the doubly forbidden $^1S_0\\to ^3P_0$ transition in bosonic $^{174}$Yb  

CERN Document Server

We report an uncertainty evaluation of an optical lattice clock based on the $^1S_0\\leftrightarrow^3P_0$ transition in the bosonic isotope $^{174}$Yb by use of magnetically induced spectroscopy. The absolute frequency of the $^1S_0\\leftrightarrow^3P_0$ transition has been determined through comparisons with optical and microwave standards at NIST. The weighted mean of the evaluations is $\

2008-01-01

440

Formation of nano-sized particles of a solid electrolyte by laser ablation  

Energy Technology Data Exchange (ETDEWEB)

Nano-sized particles of a lithium ion conductive solid electrolyte, LiTi{sub 2}(PO{sub 4}){sub 3}, were prepared by laser ablation. The obtained particles were ca. 10nm in diameter. X-ray powder diffraction and Raman spectroscopy showed that they were amorphous with local structure similar to the crystalline counterpart. They were crystallized by the heating at ca. 630{sup o}C. (author)

2005-08-26

441

FT-IR spectroscopic studies of fulvic acid from weathered coal and its complexes  

International Nuclear Information System (INIS)

FT-IR spectrum of fulvic acid from wheathered coal of Gongxian is determined using second derivative spectroscopy and the spectroscopic resolution is enhanced. Moreover, FT-IR spectra of the complexes of fulvic acid with Ca"2"+, Ba"2"+, Cu"2"+, Pb"2"+ and UO_2"2"+ under different pH are determined and the nature of the coordination of these complexes is discussed.

1995-01-01

442

External reflection absorption infrared spectroscopy study of lung surfactant proteins SP-B and SP-C in phospholipid monolayers at the air/water interface.  

UK PubMed Central (United Kingdom)

The interactions of the hydrophobic pulmonary surfactant proteins SP-B and SP-C with 1,2-dipalmitoylphosphatidylcholine in mixed, spread monolayer films have been studied in situ at the air/water interface...Full Text Available

1995-12-01

443

Enhanced Activity of Nanocrystalline Zeolites for Selective Catalytic Reduction of NOx  

Energy Technology Data Exchange (ETDEWEB)

Nanocrystalline zeolites with discrete crystal sizes of less than 100 nm have different properties relative to zeolites with larger crystal sizes. Nanocrystalline zeolites have improved mass transfer properties and very large internal and external surface areas that can be exploited for many different applications. The additional external surface active sites and the improved mass transfer properties of nanocrystalline zeolites offer significant advantages for selective catalytic reduction (SCR) catalysis with ammonia as a reductant in coal-fired power plants relative to current zeolite based SCR catalysts. Nanocrystalline NaY was synthesized with a crystal size of 15-20 nm and was thoroughly characterized using x-ray diffraction, electron paramagnetic resonance spectroscopy, nitrogen adsorption isotherms and Fourier Transform Infrared (FT-IR) spectroscopy. Copper ions were exchanged into nanocrystalline NaY to increase the catalytic activity. ...

2006-12-31

444

Electronic structure of the Ru(0001) surface  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with the electronic structure of ruthenium. Synchrotron radiation in the range from 15 to 45 eV and angle-resolved ultraviolet photoemission are used to map the energies of the electronic states. The Fermi surface of Ru is determined using angle-resolved ultraviolet photoemission spectroscopy. The experimental results are compared with calculated photoemission spectra obtained within the framework of the one-step model of photoemission. (author)

2000-03-13

445

Electronic structure of KTiOAsO_4: A comparative study by the full potential linearized augmented plane wave method, X-ray emission spectroscopy and X-ray photoelectron spectroscopy  

International Nuclear Information System (INIS)

First-principles self-consistent band-structure calculations of potassium titanyl arsenate, KTiOAsO_4 (KTA), have been made using the full potential linearized augmented plane wave (FP-LAPW) method. Total and partial densities of states of the constituent atoms of KTA have been derived. The results obtained show that the valence band of KTA is dominated by contributions of the O 2p-like states, while the Ti 3d-like states are the main contributors into the conduction band of the compound. Additionally, the FP-LAPW calculations have revealed that potassium atoms are highly ionized in KTA. In the present work, the X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) methods were also employed to investigate experimentally the electronic structure of potassium titanyl arsenate. For the mentioned compound, the XES K Ll, Ti L#alpha#, As K#beta#_2 and O K#alpha# bands reflecting the valence K s-, Ti s,d-, As p- and O p-like ...

2009-05-27

446

Effect of KI on improving copper corrosion inhibition efficiency of benzotriazole in sulfuric acid electrolytes  

Energy Technology Data Exchange (ETDEWEB)

A synergistic effect exists when benzotriazole (BTAH) and iodide ions are used together to prevent the corrosion of copper in sulfuric acid. The nature of this effect has been studied systematically by using electrochemical techniques and X-ray photoelectron spectroscopy. The synergistic effect is due largely to the formation of a film of Cu(IBTA) complex and is probably polymeric in nature. This new complex film greatly depresses copper dissolution.

1993-10-01

447

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

UK PubMed Central (United Kingdom)

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

1992-02-01

448

Effect of Atmospheric Conditions on LIBS Spectra  

Energy Technology Data Exchange (ETDEWEB)

Laser-induced breakdown spectroscopy (LIBS) is typically performed at ambient Earth atmospheric conditions. However, interest in LIBS in other atmospheric conditions has increased in recent years, especially for use in space exploration (e.g., Mars and Lunar) or to improve resolution for isotopic signatures. This review focuses on what has been reported about the performance of LIBS in reduced pressure environments as well as in various gases other than air.

2010-05-01

449

Dielectric barrier discharge using corona-modified silicone rubber  

Science.gov (United States)

Results from scanning electron microscopy, Fourier transform infrared spectroscopy and the measurement of thermally stimulated current show that a high density of the physical defects and the chemical defects are introduced into the surface of the silicone rubber plates after they are treated by corona discharge plasma. These defects behave electrically as shallow electron traps, leading to the formation of a uniform discharge in air at higher pressure when the corona-modified silicone rubber is used in dielectric barrier discharge.

2008-10-01

450

Determination of the /sup 242m/Am nuclear moments  

Energy Technology Data Exchange (ETDEWEB)

The hyperfine structure of Am atoms was investigated in an atomic beam by laser spectroscopy. The observed splittings were evaluated with respect to the magnetic dipole and electric quadrupole moments of /sup 242m/Am. The results are: ..mu../sub I/(/sup 242m/Am) = +0.97(5) nm, Q(/sup 242m/Am) = +6.5(2.0) b.

1988-07-01

451

Crystal field in RNiAl compounds studied by inelastic neutron scattering  

Energy Technology Data Exchange (ETDEWEB)

We present a study of the crystal field in PrNiAl, NdNiAl, ErNiAl and ErCuAl intermetallic compounds based on inelastic neutron spectroscopy. These compounds crystallize in the ZrNiAl-type hexagonal structure with an orthorhombic symmetry on rare-earth sites. The results are compared with the specific-heat data, and the lower parts of the crystal-field energy-level schemes are determined. (orig.)

2002-07-01

452

Crystal field in RNiAl compounds studied by inelastic neutron scattering  

International Nuclear Information System (INIS)

We present a study of the crystal field in PrNiAl, NdNiAl, ErNiAl and ErCuAl intermetallic compounds based on inelastic neutron spectroscopy. These compounds crystallize in the ZrNiAl-type hexagonal structure with an orthorhombic symmetry on rare-earth sites. The results are compared with the specific-heat data, and the lower parts of the crystal-field energy-level schemes are determined. (orig.)

2002-01-01

453

Conductive, spin-cast carbon films from polyacrylonitrile  

Energy Technology Data Exchange (ETDEWEB)

Polyacrylonitrile films have been spin cast and pyrolyzed to produce thin (500--1500 A) carbon films. These films have higher electrical conductivities than films produced by other methods at similar temperatures. The conductivity can be varied by at least four orders of magnitude by changing the pyrolysis temperature. Ultraviolet, infrared, and Raman spectroscopies were used to investigate the chemical structure of the films during different stages of processing.

1987-05-18

454

Complete spectroscopy of "8"7","8"8","8"9Sr with (n,#gamma#) and (d,p) reactions?  

International Nuclear Information System (INIS)

We conducted (n, #gamma#) and (d, p) reactions leading to "8"7", "8"8", "8"9"Sr in addition to "8"8Sr (d, t) "8"7Sr and 24 keV neutron capture in "8"8Sr. (orig./HSI).

455

Applications of Bonner sphere detectors in neutron field dosimetry  

Energy Technology Data Exchange (ETDEWEB)

The theory of neutron moderation and spectroscopy are briefly reviewed, and moderators that are useful for Bonner sphere spectrometers are discussed. The choice of the neutron detector for a Bonner sphere spectrometer is examined. Spectral deconvolution methods are briefly reviewed, including derivative, parametric, quadrature, and Monte Carlo methods. Calibration is then discussed. (LEW)

1983-09-01

456

Applications of Auger spectroscopy and ESCA to the study of thin films formed on metals  

International Nuclear Information System (INIS)

Various examples of applications of these two techniques are described. A part of them are related to the analysis of adsorbed layers formed during gaz-metal interactions. The others are concerned with the analysis of passive films formed during dry and wet corrosion. Problems related to the calibration of these techniques are discussed.

1979-05-23

457

A study of the interactions of some polypyridylruthenium (II) complexes with DNA using fluorescence spectroscopy, topoisomerisation and thermal denaturation.  

UK PubMed Central (United Kingdom)

The nature of binding of Ru(phen) 2+ (I), Ru(bipy) 2+ (II), Ru(terpy) 2+ (III) (phen = 1,10-phenanthroline, bipy 3 = 2,2'-bipyridyl, 3 terpy = 2,2'2," - 2 terpyridyl) to DNA, poly[d(G-C)] and poly[d(A-T)]...Full Text Available

1985-09-11

458

2DIR spectroscopic studies on cholic acid  

Science.gov (United States)

Based on our cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, the two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectra. .

2000-03-01

459

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

UK PubMed Central (United Kingdom)

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

1990-06-01

460

Voiding and Sexual Function after Autonomic-Nerve-Preserving Surgery for Rectal Cancer in Disease-Free Male Patients  

UK PubMed Central (United Kingdom)

PurposeWe evaluated the effects of surgery for rectal cancer on postoperative voiding and sexual function over the course of time.Materials and MethodsData...Full Text Available

2010-12-01

461

The scattering amplitude for four off-shell tachyons from functional integrals  

International Nuclear Information System (INIS)

We use functional integral techniques to calculate the scattering amplitude for four open off-shell tachyons in Witten's string field theory and show that the residues of the first three poles agree with those obtained using oscillator methods. (orig.).

462

The long lifespan of two bat species is correlated with resistance to protein oxidation and enhanced protein homeostasis  

UK PubMed Central (United Kingdom)

Altered structure, and hence function, of cellular macromolecules caused by oxidation can contribute to loss of physiological function with age. Here, we tested whether the lifespan of bats, which generally...Full Text Available

2009-07-01

463

The human Tp53 Arg72Pro polymorphism explains different functional prognosis in stroke  

UK PubMed Central (United Kingdom)

The functional outcome after stroke is unpredictable; it is not accurately predicted by clinical pictures upon hospital admission. The presence of apoptotic neurons in the ischemic penumbra and perihematoma...Full Text Available

2011-03-14

464

The functional analysis of problematic verbal behavior  

UK PubMed Central (United Kingdom)

This study describes procedures and outcomes in a functional analysis of problem behavior of 2 public school students. For a 13-year-old honors student, bizarre tacts (labeled as psychotic speech by...Full Text Available

2002-01-01

465

The associations between serum sex hormones, erectile function, and sex drive  

UK PubMed Central (United Kingdom)

Few studies have examined the association between sex hormone serum levels, erectile function, and sex drive. Using data from the Olmsted County Study of Urinary Symptoms and Health Status among...Full Text Available

2008-09-01

466

Specialization along the Left Superior Temporal Sulcus for Auditory Categorization  

UK PubMed Central (United Kingdom)

The affinity and temporal course of functional fields in middle and posterior superior temporal cortex for the categorization of complex sounds was examined using functional magnetic resonance imaging...Full Text Available

2010-12-01

467

Sequence features that drive human promoter function and tissue specificity  

UK PubMed Central (United Kingdom)

Promoters are important regulatory elements that contain the necessary sequence features for cells to initiate transcription. To functionally characterize a large set of human promoters, we measured...Full Text Available

2010-07-01

468

Scattering amplitude for four off-shell tachyons from functional integrals  

Energy Technology Data Exchange (ETDEWEB)

We use functional integral techniques to calculate the scattering amplitude for four open off-shell tachyons in Witten's string field theory and show that the residues of the first three poles agree with those obtained using oscillator methods.

1988-05-30

469

Rome III: The functional gastrointestinal disorders, third edition, 2006  

UK PubMed Central (United Kingdom)

Functional gastrointestinal disorders (FGIDs) represent a common and important class of disorders within gastroenterology. RomeI, the first edition was published in 1994, with symptom-based diagnostic...Full Text Available

2008-04-07

470

Rome II Versus Rome III Classification of Functional Gastrointestinal Disorders in Pediatric Chronic Abdominal Pain  

UK PubMed Central (United Kingdom)

ObjectivesThe updated Rome III criteria for pediatric functional gastrointestinal disorders (FGIDs) include new FGID categories and changes to the Rome II criteria...Full Text Available

2008-09-01

471

Renal functions in pediatric patients with beta-thalassemia major: relation to chelation therapy: original prospective study  

UK PubMed Central (United Kingdom)

BackgroundIn β-thalassemia, profound anemia and severe hemosiderosis cause functional and physiological abnormalities in various organ systems. In recent years, there have...Full Text Available

472

Relation of Kidney Function and Albuminuria with Atrial Fibrillation (From the Heart and Soul Study)  

UK PubMed Central (United Kingdom)

Atrial fibrillation (AF) is common in end-stage renal disease (ESRD), but the relationship between more modest decrements in kidney function or albuminuria with AF is uncertain. Among 956 outpatients...Full Text Available

2009-12-01

473

Recognizing brain activities by functional near-infrared spectroscope signal analysis  

UK PubMed Central (United Kingdom)

BackgroundFunctional Near-Infrared Spectroscope (fNIRs) is one of the latest technologies which utilize light in the near-infrared range to determine brain activities. Near-infrared...Full Text Available

474

REVERSAL LEARNING SET AND FUNCTIONAL EQUIVALENCE IN CHILDREN WITH AND WITHOUT AUTISM  

UK PubMed Central (United Kingdom)

To evaluate whether children with and without autism could exhibit (a) functional equivalence in the course of yoked repeated-reversal training and (b) reversal learning set, 6 children, in...Full Text Available

2008-01-01

475

Purification of functional baculovirus particles from silkworm larval hemolymph and their use as nanoparticles for the detection of human prorenin receptor (PRR) binding  

UK PubMed Central (United Kingdom)

BackgroundBaculovirus, which has a width of 40 nm and a length of 250-300 nm, can display functional peptides, receptors and antigens on its surface by their fusion with a baculovirus...Full Text Available

476

Psychopathological features of irritable bowel syndrome patients with and without functional dyspepsia: a cross sectional study  

UK PubMed Central (United Kingdom)

BackgroundIrritable bowel syndrome (IBS) and functional dyspepsia (FD) show considerable overlap and are both associated with psychiatric comorbidity. The present study aimed to...Full Text Available

477

Prostaglandin-mediated closure of paracellular pathway and not restitution is the primary determinant of barrier recovery in acutely injured porcine ileum  

UK PubMed Central (United Kingdom)

SUMMARYSmall bowel epithelium is at the frontline of intestinal barrier function. Restitution is considered to be the major determinant of epithelial repair as function recovers...Full Text Available

2003-11-01

478

Original Research Article: Longitudinal Relationships of Depressive Symptoms to Pain Intensity and Functional Disability Among Children with Disease-Related Pain  

UK PubMed Central (United Kingdom)

ObjectiveTo examine the longitudinal relationship between depressive symptoms at study entry (T1) on pain intensity (PI) and functional disability over a 1-year period...Full Text Available

2006-01-01

479

Ordered Assembly of the Adhesive and Electrochemical Connections within Newly Formed Intercalated Disks in Primary Cultures of Adult Rat Cardiomyocytes  

UK PubMed Central (United Kingdom)

The intercalated disk (ID) is a complex structure that electromechanically couples adjoining cardiac myocytes into a functional syncitium. The integrity of the disk is essential for normal cardiac function,...Full Text Available

2010-01-01

480

Ontogenetic Profile of the Expression of Thyroid Hormone Receptors in Rat and Human Corpora Cavernosa of the Penis  

UK PubMed Central (United Kingdom)

IntroductionIn the last few years, various studies have underlined a correlation between thyroid function and male sexual function, hypothesizing a direct action of thyroid hormones...Full Text Available

2010-04-01

481

Non-Boolean almost perfect nonlinear functions on non-Abelian groups  

CERN Document Server

The purpose of this paper is to present the extended definitions and characterizations of the classical notions of APN and maximum nonlinear Boolean functions to deal with the case of mappings from a finite group K to another one N with the possibility that one or both groups are non-Abelian.

2011-01-01

482

Modulation of leg muscle function in response to altered demand for body support and forward propulsion during walking  

UK PubMed Central (United Kingdom)

A number of studies have examined the functional roles of individual muscles during normal walking, but few studies have examined which are the primary muscles that respond to changes in external...Full Text Available

2009-05-11

483

Massive turnover of functional sequence in human and other mammalian genomes  

UK PubMed Central (United Kingdom)

Despite the availability of dozens of animal genome sequences, two key questions remain unanswered: First, what fraction of any species' genome confers biological function, and second, are apparent...Full Text Available

2010-10-01

484

Mammalian Sirt1: insights on its biological functions  

UK PubMed Central (United Kingdom)

Sirt1 (member of the sirtuin family) is a nicotinamide adenosine dinucleotide (NAD)-dependent deacetylase that removes acetyl groups from various proteins. Sirt1 performs a wide variety of functions...Full Text Available

485

Internal Functionalization and Surface Modification of Vinylsilsesquioxane Nanoparticles  

UK PubMed Central (United Kingdom)

The interior of 237 nm spherical vinylsilsesquioxane nanoparticles has been covalently modified and their surface functionalized under mild conditions to yield a novel type of hybrid silsesquioxane...Full Text Available

2009-01-01

486

Impairment and recovery of left motor function in patients with right hemiplegia.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To assess the motor function of the left, supposedly unaffected, limbs of patients with an acute right vascular hemiplegia. METHODS: Fifteen patients with an acute vascular right hemiplegia...Full Text Available

1997-01-01

487

Impact of Lifelong Sedentary Behavior on Mitochondrial Function of Mice Skeletal Muscle  

UK PubMed Central (United Kingdom)

This study investigated the impact of lifelong sedentariness on skeletal muscle mass and mitochondrial function. Thirty C57BL/6 strain mice (2 months) were randomly divided into three groups (young-Y;...Full Text Available

2009-09-01

488

Identification and Functional Relevance of de novo DNA Methylation in Cancerous B-Cell Populations  

UK PubMed Central (United Kingdom)

Epigenetic remodeling is a hallmark of cancer, with the frequent acquisition of de novo DNA methylation in CpG islands. However, the functional relevance of de novo...Full Text Available

2010-03-01

489

Functional Interactions between Retinoblastoma and c-MYC in a Mouse Model of Hepatocellular Carcinoma  

UK PubMed Central (United Kingdom)

Inactivation of the RB tumor suppressor and activation of the MYC family of oncogenes are frequent events in a large spectrum of human cancers. Loss of RB function and MYC activation are thought to...Full Text Available

490

Functional Characterization and Partial Purification of the Ubiquinol-Cytochrome c Oxidoreductase from Higher Plant Mitochondria (Helianthus tuberosus) 1  

UK PubMed Central (United Kingdom)

The functional and thermodynamic characteristics of the ubiquinolcytochrome (Cyt) c oxidoreductase in a Cyt b/c1-enriched fraction (defined...Full Text Available

1985-03-01

491

Fluctuation properties of strength function phenomena: A model study  

Energy Technology Data Exchange (ETDEWEB)

We study fluctuation properties of strength function phenomena by employing a quantum mechanical model where a single parent state couples with a large number of background states. The background system is devised in such a way that the classical dynamics of the system may show a regular, an irregular, or a chaotic character as a function of a single parameter. The coupling of the parent state to the background states produces a fragmentation of the parent state, giving rise to a strength function phenomenon. We study various measures of the strength function that characterize its bulk structure or fluctuation properties. They include energy moments, strength distribution, fractal dimensions of the strength function, and Fourier transform of the autocorrelation function. Some of these measures, such as strength distribution or Fourier transform of the ...

1997-07-01

492

Expression and purification of a functional human hepatitis B virus polymerase  

UK PubMed Central (United Kingdom)

AIM: To identify a method for efficient large-scale purification of functional hepatitis B virus polymerase (HBV-Pol) without addition of cellular factors.METHODS: Full-length HBV-Pol (843 amino...Full Text Available

2010-12-07

493

Effects of Intrathecal Baclofen on Perceived Sexual Functioning in Men With Spinal Cord Injury  

UK PubMed Central (United Kingdom)

Background/Objective:Reports in the literature suggest that administration of intrathecal baclofen to control spasticity may have deleterious effects on erectile function...Full Text Available

2008-01-01

494

Effect of a mixture of micronutrients, but not of bovine colostrum concentrate, on immune function parameters in healthy volunteers: a randomized placebo-controlled study  

UK PubMed Central (United Kingdom)

BackgroundSupplementation of nutritional deficiencies helps to improve immune function and resistance to infections in malnourished subjects. However, the suggested benefits of dietary...Full Text Available

495

Determinants of female sexual function in inflammatory bowel disease: a survey based cross-sectional analysis  

UK PubMed Central (United Kingdom)

BackgroundSexual function is impaired in women with inflammatory bowel disease (IBD) as compared to normal controls. We examined disease specific determinants of different aspects...Full Text Available

496

CLASSROOM APPLICATION OF A TRIAL-BASED FUNCTIONAL ANALYSIS  

UK PubMed Central (United Kingdom)

We evaluated a trial-based approach to conducting functional analyses in classroom settings. Ten students referred for problem behavior were exposed to a series of assessment trials, which were interspersed...Full Text Available

2011-01-01

497

Behavioral consequences of dopamine deficiency in the Drosophila central nervous system  

UK PubMed Central (United Kingdom)

The neuromodulatory function of dopamine (DA) is an inherent feature of nervous systems of all animals. To learn more about the function of neural DA in Drosophila, we generated mutant...Full Text Available

2011-01-11

498

Association between a functional polymorphism in the serotonin transporter gene and diarrhoea predominant irritable bowel syndrome in women  

UK PubMed Central (United Kingdom)

Background and aims: Serotonin (5-hydroxtryptamine, 5-HT) is an important factor in gut function, playing key roles in intestinal peristalsis and secretion, and in sensory...Full Text Available

2004-10-01

499

Assessing the Left Ventricular Systolic Function at the Bedside: The Role of Transpulmonary Thermodilution-Derived Indices  

UK PubMed Central (United Kingdom)

Evaluating the systolic function of the left ventricle (LV) is important in the hemodynamic management of the critically ill patients with circulatory failure. Echocardiography is considered the standard...Full Text Available

2011-01-01

500

Age-dependent changes in Ca2+ homeostasis in peripheral neurones: implications for changes in function  

UK PubMed Central (United Kingdom)

Calcium ions represent universal second messengers within neuronal cells integrating multiple cellular functions, such as release of neurotransmitters, gene expression, proliferation, excitability,...Full Text Available

2007-06-01