bluuebunny/crossref_metadata_2025 huggingface dataset:
Attenuated Total Reflection Surface-Enhanced Infrared Absorption Spectroscopy at a Cobalt Electrode
Authors: Huo Sheng-Juan , Wang Jin-Yi , Sun Da-Lin , Cai Wen-Bin
Published: October 2009

In situ surface-enhanced infrared absorption spectroscopy (SEIRAS) in attenuated total reflection (ATR) configuration has been extended to a Co electrode fabricated by potentiostatic deposition of a 50-nm-thick Co overlayer onto a Au underlayer chemically preformed on the reflecting plane of an ATR Si hemi-cylindrical prism. The as-prepared Co-on-Au film was characterized with atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The AFM images of the films before and after Co coating revealed island structures facilitating the SEIRA effect with Co nanoparticles much smaller than the underlying Au ones. The XPS spectrum did not contain any characteristic peaks related to Au, suggestive of a virtually pinhole-free nature of the Co overlayer. The voltammetric response of the as-prepared films in phosphate buffer solution (PBS, pH 6.9) was characteristic of a polycrystalline bulk Co electrode. Normally directed unipolar bands were found for surface probe CO molecules on Co surfaces in the PBS with their major band (COl) intensity being one order of magnitude higher than that obtained with conventional IR reflection–absorption spectroscopy (IRRAS). By taking advantage of the higher detection sensitivity, the bands for linearly bonded CO (COl) at 1965–2005 cm−1 and the multi-bonded (COm) band at 1845–1875 cm−1 were clearly detected with their Stark tuning rates being 59 and 63 cm−1•V−1, respectively, which would be otherwise unobtainable with the conventional IRRAS in the neutral solution.
The Effect of Spectrometer Slit Width on Intensity of Atomic Emission Lines in Emission Flame Photometry and the Effect of Source Line Width on Absorbance of Atomic Absorption Lines in Absorption Flame Photometry
Authors: Winefordner J. D.
Published: October 2009

In atomic emission and atomic absorption spectroscopy, the measured instrumental signal and its relationship with concentration is of great importance. Relationships between the measured intensity and the theoretical intensity or the integrated intensity as a function of spectrometer band width and slit width and the relationships between measured absorbance and the theoretical absorbance or the integrated absorbance as a function of atomic source line width are given A number of conclusions are drawn regarding the measured parameter. In atomic emission flame photometry, it is shown that the measured intensity usually is proportional to the theoretical integrated line intensity and is independent of the half-width of the atomic emission line In atomic absorption flame photometry, the measured absorbance is proportional to the theoretical absorbance and is independent of the atomic absorption line width as long as the source line width is much narrower than the atomic absorption line width.
Automatic Controller and Data Printer for Use with a Philips Three Position Spectrograph
Authors: Jones J. H. , Heine K. S. , Williams R. F.
Published: October 2009

This report describes equipment that converts a Philips Three Position X-Ray Spectrograph to semiautomatic operation for routine sample analysis. Up to ten independent sets of conditions for wavelength (2θ), pulse height analysis baseline, and total count can be selected in advance. The equipment will then automatically determine the “counting time” for a sample for each set of conditions selected At the end of each count the equipment prints out the sample number, code numbers for the goniometer position, baseline setting, the fixed count used, and the time, in tenths of a sec, required to reach the fixed count. Semiautomatic operation permits operation by personnel with minimum training, reduces invalid results due to operator mistakes, and increases sample output per day The results are identical with those obtained by manual operation
Emission Spectroscopy without Emulsion Calibration Curve. The Spectro-nomograph Chart
Authors: Trandafir Nicolae
Published: October 2009

The spectrographs properties of the sample and the characteristics of the photographic emulsion can be taken into account simultaneously through a parameter, α, representing the slope of the analytical curve This paper describes an analytical procedure (the parametric method) that introduces into the calculation α of the function instead of γ of the photographic emulsion. This substitution of parameters leads to automation of the spectrochermcal calculations The unknown concentration of an element can be calculated with a standard formula, free of γ, by making use of a digital computer or by plotting analytical curves on the “Spectro-nomograph” chart directly from transmissions. In both cases this technique eliminates the determination of the intensity ratios. The principles of the method and the mathematical derivation of the chart are given.
Spectrographic Analysis of High Purity Gold Plate
Authors: Shubin Lester D. , Chaudet Julian H.
Published: October 2009

Determinations of trace impurities in high purity gold plate were made by emission spectroscopy at concentration levels of 0 001 to 0 1% Trace contaminants included Al, Cu, Si, Mg, Ni, Fe, Pb, and Ag. Contamination problems related to the handling of the gold plate were minimized by electrolytically depositing the gold on graphite electrodes followed by dissolution of the plate in a suitable solvent. Emission spectra were obtained on the resultant solution using high voltage ac arc excitation and vacuum cup electrodes
An Investigation into the Analysis of Nitrogen for Hydrogen by Emission Spectroscopy
Authors: Dickinson G. W. , Wheeler G. V.
Published: October 2009

Continuous monitoring of hydrogen in flowing nitrogen gas was needed in connection with experimental work at the USAEC's National Reactor Testing Station. One of the methods investigated was emission spectroscopy, using quartz envelope electrodeless discharge tube excitation. The sample gas was passed through a cold trap to eliminate water vapor and hydrocarbon vapors before entering the discharge tube at a pressure of two mm Hg. Using a grating monochromator with photomultiplier detection set at 4861.3A hydrogen can be determined down to about 0.05% (v/v).
The Infrared Spectra of Some New Derivatives of S-Triazine
Authors: Loughran G. A. , Ehlers G. F. L. , Crawford W. J. , Burkett J. L. , Ray J. D.
Published: October 2009

The infrared spectra of a number of new ethers, amino derivatives, and sulfur-containing s-triazines have been obtained in the region between 3333 and 670 cm−1. An interpretation of the spectra is given and some new assignments are made In addition the existance of certain hydroxy and thiol derivatives in the keto and thioketo configuration is shown
A Study of the Efficiency of Spectrochemical Buffers. I. Influence of Buffer Cations
Authors: Maritz F. R. , Strasheim A.
Published: October 2009

A method is described for the determination of the efficiency of spectrochemical buffers by using the differences in intensity values of the analytical lines of a group of elements contained in different matrices. By an analogous calculation, efficiency can also be determined using temperature index values. Efficiency values, in both cases, are given as numerical values. A study of five different cations was completed, and the results are given.
Mass Spectra of Some Bis(Alkylmercapto)alkanes
Authors: Shuttleworth T. H.
Published: October 2009

Mass spectra of seventeen bis(alkylmercapto) alkanes of the general formula R.S.CnH2nS R are presented and discussed Major ions occur by 1) simple C-C or C-S cleavage to give ions of the type R S CmH2m+1+; 2) cleavage of a C-S bond accompanied by hydrogen rearrangement; and 3) further loss of an alkyl group. The consecutive nature of breakdown in cases of double cleavage and rearrangement is established by metastable transitions.
Evaluation of Rotating Platform Technique for the Spectrochemical Analysis of Blood Cells
Authors: Szivek John , Gilders Eleanor J. , Holt John M. , Valberg Leslie S.
Published: October 2009

A rotating platform technique is described for the spark analysis of ashed red blood cells with the direct reading spectrograph. A study was made of the effect of different variables that included the size and shape of the counter electrode, the density and surface configuration of the platform electrode, and the mode of sample application It indicated that a 0.2 5 in. flat tip counter electrode, a flat platform electrode precoated with phcene, and one mg of sample residue to which a wetting agent had been added to facilitate sample application produced the best combination of sensitivity and reproducibility. The technique provided greater sensitivity than methods employing the rotating disc electrode, flat top electrode and the plastic cup electrode. Normal values are given for Ca, Mg, Cu, and Zn in red blood cells.
High Speed Electromechanical Shutter for Time Resolved Spectroscopy
Authors: Kendall P. A.
Published: October 2009

Time resolved spectroscopy can be obtained using the ordinary time integrating spectrograph and the very rapid response, high speed electromechanical shutter described in this paper. The interacting magnetic field between parallel wire segments of a small flattened insulated wire set up by a high current surge is used to deliver, by the motion of a wire segment, a very rapid high amplitude impulse to a low mass slotted plate. The resultant high velocity motion of the slotted plate uncovers the spectrographic slit, keeps it open for a calibrated time, and then closes it. The present range of open times used is from 5 0 to 1000 μsec.
Polarization Modulated Excitation Spectroscopy
Authors: Kaye Wilbur
Published: October 2009

An accessory has been designed for the Beckman Model DK spectrophotometers for automatic recording of polarization modulated excitation spectra. The polarizer is continuously rotated while the excitation spectrum is scanned with the monochromator The absorption, fluorescence, excitation and polarization spectra of rhodamine B in glycerol are used to illustrate performance.
X-Ray Fluorescence Analysis of Biological Tissues
Authors: Alexander Geo. V.
Published: October 2009

The application of conventional x-ray fluorescence equipment to the analysis of biological tissues is discussed. Several examples are given to indicate the type of procedure which is involved The integration of x-ray fluorescence and optical emission methods for a rather efficient analysis of biological tissues is outlined.
Analysis of the NMR Spectrum of Phenylethane-1,2-Dithiol
Authors: Forbes J. W. , Jungnickel J. L.
Published: October 2009

The NMR spectrum of phenylethane-1,2-dithiol has been analyzed completely (except for the aromatic protons) by Reilly's new computer program MARIPI which is based on the Swalen and Reilly programs NMRIT and NMRENI. The geminal coupling constant, J34, was assumed to be negative in accord with the recent theoretical and experimental evidence on the signs of (H,H) coupling constants. The magnitudes of the two vicinal H-C-C-H coupling constants, J35 and J45, indicate that the molecule exists primarily in the two forms with gauche-trans arrangement of the hydrogen atoms on these carbon atoms The H-C-S-H coupling constants, J13, J14, and J25, can be either positive or negative in sign; however, a positive sign is favored in line with the –, +, – pattern of sign-alternation for (H,H) coupling across 2, 3, and 4 bonds. The long-range coupling constants, J15, J23, and J24, are small and probably negative. The very long-range coupling between the S-H protons, J12, is too small to be determined
A Determination of the Absorption and Scattering of Visible and Ultraviolet Light by Six Species of Protozoa
Authors: Calkins John
Published: October 2009

Some of the optical properties of six strains of protozoa were determined. The loss of transmitted intensity resulting from scattering and true absorption was calculated.
Theory of a Double Polarization Modulated Martin-Puplett Interferometer
Authors: Da Costa V. M. , Coleman L. B.
Published: October 2009

We present a formal Jones matrix analysis of a new far-infrared spectrometer design based on the Martin-Puplett interferometer. The new spectrometer utilizes double polarization modulation and eliminates problems due to source fluctuations, instrumental drift, and reduced dynamic range in studies of materials with small absorptivities. The spectrometer has successfully extended the reflection-absorption technique of thin-film spectroscopy into the far-infrared and millimeter wave region.
Hadamard Transform Raman Microscopy of Laser-Modified Graphite Electrodes
Authors: Treado Patrick J. , Govil Anurag , Morris Michael D. , Sternitzke Kent D. , McCreery Richard L.
Published: October 2009

In this communication, we describe the application of Hadamard transform Raman microscopy to the imaging of edge plane microstructures in laser-modified highly ordered pyrolitic graphite (HOPG) electrodes. Hadamard transform Raman microscopy is a highly selective method of analysis which can image thermally sensitive materials at micron-scale spatial resolution. The technique is capable of imaging relatively weak Raman scatterers in only a few minutes. The current multichannel microscope generates images having 255 × 256 pixels. In addition, we characterize an imaging artifact present in our current system, as well as apply a first-order correction for the problem.
Qualitative Information from Multivariate Calibration Models
Authors: Seasholtz Mary Beth , Kowalski Bruce R.
Published: October 2009

Multivariate calibration methods are implicit modeling methods as opposed to explicit methods that impose a theoretical model on the experimental data. Because these methods incorporate variance in the data not necessarily related to the property of interest, implicit models should be both quantitatively and qualitatively validated. Qualitative validation using the regression vector is discussed here. When the regression vector found by calibration is multiplied by the response vector of an unknown sample, it gives an estimate of the property of interest. When used with spectroscopy, the regression vector contains information about the pure spectrum of the analyte of interest, but ambiguities exist because of mathematical constraints that hinder direct extraction of this information. Results from simulated data show that, if the measured data are all positive, the presence of negative regions in the regression vector indicates overlap between the pure spectra of the analyte of interest and the interferent(s), and the qualitative information is limited. Transformations using derivatives are presented that help remove some of the ambiguity. For two-component linear systems, the derivative of the pure spectrum of the interferent component can be calculated. With multicomponent systems, derivative transformations locate some peak maxima in the pure spectra of the interferent components.
The Excitation-Emission Matrix in Fluorescence Line-Narrowing Spectroscopy: A Study of Oxazine-4-Perchlorate in Polyvinylbutyral
Authors: Hofstraat Johannes W. , Locher René , Wild Urs P.
Published: October 2009

The full information of the luminescence intensity as a function of excitation and emission wavenumber is contained in the excitation-emission matrix (EEM). An equal intensity contour plot of this EEM allows a convenient two-dimensional presentation of the experimental findings. In FLN spectra the excitation step selects one or more subsets of molecules which are excited into the S1 state. Such spectra depend intrinsically on the excitation wavenumber, and their interpretation is greatly facilitated by study of their contour plots. This technique is applied to oxazine-4-perchlorate in PVB, which shows a very broad inhomogeneous width in comparison to its vibrational spacings and which is therefore difficult to interpret with conventional one-dimensional methods.
New Interpolation Formulas for Apodized, Magnitude-Mode Fourier Transformed Spectra
Authors: Goto Yutaka , Hosokawa Takahito , Mitani Masaaki , Inoue Masao
Published: October 2009

Interpolation techniques for the magnitude-mode discrete Fourier transformed (DFT) spectra of exponentially damped sinusoids have been developed. However, simple formulas to interpolate the apodized DFT spectra have not been given, except those used to interpolate the Hanning-apodized spectra. In this paper, we derive simple interpolation formulas using the sine-bell and rectangle windows. It is found that the formulas for the rectangle window are essentially identical to Lorentzian interpolation. Furthermore, we derive generalized formulas to interpolate DFT spectra apodized by a family of sin α( X) windows, which includes the rectangle, sine-bell, and Hanning windows. We call the proposed interpolation “generalized” because any integer value of α can be used. Simulation results show that the accuracy of interpolation is improved remarkably with increases in the value of the parameter α.
Analysis of Polynuclear Aromatic Hydrocarbon Mixtures Desorbed from Particulate Matter in a Low-Temperature Matrix by Shpol'skii Time-Resolved Fluorescence Spectroscopy
Authors: Bark Ki-Min , Forcé R. Ken
Published: October 2009

A simple approach for analyzing mixtures of polynuclear aromatic hydrocarbons (PAH) desorbed from particulate matter that does not involve any separations was studied with the use of anthracene, pyrene, and fluoranthene as model compounds. PAH absorbed on alumina was vaporized at elevated temperature in a sample cell and mixed with vapor-phase n-hexane in a stream of helium carrier gas. This gaseous mixture flowed through a nozzle into a vacuum chamber and was condensed onto a cold finger at 77 K to form a Shpol'skii matrix. In the time-resolved fluorescence emission spectra obtained for this low-temperature matrix, selectivity is improved relative to room-temperature studies. If the excitation wavelength of the source is changed, the identification of PAH in mixtures was further improved. The detection limits were less than 10 ng for pyrene and anthracene and 100 ng for fluoranthene, with 337.1-nm excitation.
A New Approach to the Study of Human Solid Tumor Cells by Means of FT-IR Microspectroscopy
Authors: Benedetti Enzo , Teodori Laura , Trinca Maria Luisa , Vergamini Piergiorgio , Salvati Franco , Mauro Francesco , Spremolla Giuliano
Published: October 2009

Cells coming from normal and neoplastic human lung tissue were analyzed by means of FT-IR microspectroscopy. Among the various methods tested to isolate the cells, mechanical treatment alone was found to yield the best results. Monolayers of cells were homogeneously distributed by cytocentrifuge preparation on BaF2 windows, and several spectra were obtained for different circular micro-areas of the order of one hundred microns in diameter. This procedure made it possible to obtain reliable spectra and to reject those containing additional bands due to impurities arising from the isolation treatment. Spectral differences between normal and neoplastic cells reflect an increase in the intensity of the bands corresponding mainly to PO2− symmetrical and asymmetrical vibrations of DNA in pathological samples with respect to normal ones. The value of the ratio of the integrated areas of the bands at 1080 and 1540 cm−1 due to DNA and proteins, respectively, makes it possible to differentiate between normal and abnormal cells, thus suggesting the use of this parameter as an original approach in the recognition of early neoplastic transformation undetectable by means of traditional procedures.
Proton NMR Analysis of Octane Number for Motor Gasoline: Part V
Authors: Ichikawa M. , Nonaka N. , Amano H. , Takada I. , Ishimori S. , Andoh H. , Kumamoto K.
Published: October 2009

A method to predict the octane number of automobile gasoline containing methyl tert-butyl ether (MTBE) by proton magnetic resonance (PMR) spectrometry was studied. Samples of gasoline whose octane numbers had been identified according to the ASTM standards (commercially available premium gasoline to which MTBE was added at rates of 7 vol % and 14 vol %) were used in this investigation of the effect of MTBE on the octane number. The findings were utilized to introduce a term regarding MTBE into the previously reported linear regression equation for estimating the octane number from the PMR spectrum, and the appropriateness of the linear regression equation was assessed. As a result, the MTBE contents in the samples were determined with satisfactory accuracy by using a standard addition method, and a linear regression equation reflecting the effect of MTBE was obtained. These achievements are reported.
Raman Spectroscopic Studies of Amsacrine
Authors: Butler Catherine A. , Cooney Ralph P. , Denny William A.
Published: October 2009

Amsacrine (4′-(9-acridinylamino)methanesulfon- m-anisidide) in both solid and aqueous forms was characterized with the use of resonance and nonresonance Raman spectroscopy (including FT-Raman spectroscopy). Evidence that the acridine nucleus is the dominant chromophoric unit contributing to the resonance Raman spectrum is based upon the apparent similarities of the spectra of aqueous amsacrine (in the unpro-tonated form) and acridine (in ethanol). The probable non-coplanarity of the acridine and phenyl units in the amsacrine molecule (based on previously reported crystal structure data) is consistent with the suggestion that the acridine nucleus may constitute an independent chromophoric unit. Further evidence is derived from analysis of the UV-visible spectrum, which indicates that excitation at 457.9 nm falls within an electronic transition of the acridine nucleus of amsacrine. The excitation profiles of aqueous amsacrine are presented, and four types of profiles have been identified.
Reagentless Near-Infrared Determination of Glucose in Whole Blood Using Multivariate Calibration
Authors: Haaland David M. , Robinson M. Ries , Koepp Gary W. , Thomas Edward V. , Eaton R. Philip
Published: October 2009

Noninvasive monitoring of glucose in diabetic patients is feasible with the use of near-infrared spectroscopic measurements. As a step toward the final goal of the development of a noninvasive monitor, the near-infrared spectra (4250 to 6600 cm−1) of glucose-doped whole blood samples were obtained along with reference glucose values. Glucose concentrations and spectra of blood samples obtained from four subjects were subjected to multivariate calibration with the use of partial least-squares (PLS) methods. The cross-validated PLS standard errors of prediction for glucose concentration based on data obtained from each individual subject's blood samples averaged 33 mg/dL over the range from 3 to 743 mg/dL. Cross-validated standard errors for glucose concentration from PLS calibrations based on data from all four subjects were 39 mg/dL. However, when PLS models based upon three subjects' data were used for prediction on the fourth, glucose prediction abilities were poor. It is suggested that blood chemistry differences were sufficiently different for the four subjects to require that a larger number of subjects be included in the calibration for adequate prediction abilities to be obtained from near-infrared spectra of blood from subjects not included in the calibration.
Infrared Study of Some Organophosphorus Esters in Carbon Tetrachloride and/or Chloroform 1% Solutions
Authors: Nyquist R. A. , Puehl C. W.
Published: October 2009

Solvent systems such as CHCl3/CCl4 or CDCl3/CCl4 are useful in showing that organophosphorus esters do exist as rotational isomers in solution. The functional groups such as P=O and POR in organophosphorus esters are the sites of solute/solvent interaction, since their group frequencies are more affected than group frequencies arising primarily within the R group of the organophosphorus esters. This study also shows that different complexes are formed between the solute and solvent systems as well as within the solvent system as the mole % CHCl3/CCl4 or CDCl3/CCl4 increases.
Requirements for Thermal Analysis by Variable-Temperature Diffuse Reflectance Infrared Spectroscopy
Authors: White Robert L.
Published: October 2009

The effect of temperature on diffuse reflectance infrared spectroscopy measurements is discussed. Instrumental parameters that determine the accuracy of variable-temperature diffuse reflectance Fourier transform infrared spectroscopy (VT-DRIFTS) measurements are identified, and methods for removing baseline artifacts resulting from fluctuations in these parameters are given. Procedures for extracting structure-specific quantitative information from DRIFTS spectra acquired at different temperatures are outlined. The use of VT-DRIFTS to generate vibration-specific absorbance band intensity and center frequency temperature profiles for calcium oxalate monohydrate is described, and correlations between these profiles and the known thermal behavior of calcium oxalate monohydrate are given.
Technique for Producing Capillaries with Reproducible Orifice Diameters for Uniform Droplet Generation
Authors: Galley Paul J. , Hieftje Gary M.
Published: October 2009

A procedure is described for fabricating capillary orifice tips useful for the generation of uniform droplets. These generator tips operate at relatively low applied pressure, are relatively resistant to clogging, and incorporate orifice diameters reproducible to 1%. The method involves implanting a fused-silica capillary within a glass sleeve. When heated, the glass and fused silica wet to form a tight seal with no cracking caused by differences in thermal expansion. This technique permits the routine production of capillary tips with fixed orifice and outer diameters.
Molten KF-AIF3 System: A Study by Raman Spectroscopy
Authors: Tixhon E. , Robert E. , Gilbert B.
Published: October 2009

Molten AIF3-KF mixtures have been investigated in a wide composition range by Raman spectroscopy and with the use of a graphite windowless cell. The results of this study clearly show that the most intense spectrum components are made of three distinct bands whose intensities vary when the composition is changed. The most probable interpretation of our data is to consider the existence of an equilibrium between AIF63–, AIF52–, and AIF4−. This explanation is a confirmation of the conclusions of recent papers suggesting the presence of these species in similar AIF3-NaF mixtures. The presence of only one major polarized band for AIF52– is explained by considering a fast exchange between the axial and equatorial fluoride at the elevated experimental temperature (1300 K). A quantitative analysis of the distribution of the fluoroaluminate species has been performed by decomposition of the Raman-band envelope. The calculated equilibrium constants (expressed in mole fraction units) for AIF52– ⇌ AIF4− + F− and AIF63– ⇌ AIF52– + F− are KA = 0.11 ± 0.01 and KB = 5 ± 1, respectively. Compared with the NaF-AIF, system, these constants correspond to a stabilization of less coordinated fluoroaluminates when the size of the counterion increases.
Versatile Cryostated Optically Transparent Thin-Layer Electrochemical (OTTLE) Cell for Variable-Temperature UV-Vis/IR Spectroelectrochemical Studies
Authors: Hartl F. , Luyten H. , Nieuwenhuis H. A. , Schoemaker G. C.
Published: October 2009

This article describes the construction of a novel optically transparent thin-layer electrochemical (OTTLE) cell for IR and UV-Vis spectroelectrochemical experiments at variable temperature. The cell has a three-electrode set melt-sealed into a smooth polyethylene spacer which is sandwiched between two CaF2 windows. The width of this spacer (0.18–0.20 mm) defines the thickness of the thin solution layer. The whole electrode assembly is housed in a thermostated Cu block of the OTTLE cell which fits into a double-walled nitrogen-bath cryostat. The experimental setup permits relatively fast electrolysis within the tested temperature range of 295 to 173 K under strictly anaerobic conditions and protection of light-sensitive compounds. Other important merits of the cell design include lack of leakage, facile cleaning, almost negligible variation of the preset temperature, and facile manipulation in the course of the experiments. The applicability of the variable-temperature IR/UV-Vis OTTLE cell is demonstrated by stabilization of a few electrogenerated carbonyl complexes of Mn(I) and Ru(II) with 3,5-di- tert. butyl-1,2-benzo(semi)quinone (DB(S)Q) and N, N′-diisopropyl-1,4-diaza-1,3-butadiene (iPr-DAB) ligands, respectively, at appropriately low temperatures.
Infrared Spectra of 34S Thionophosphate Esters
Authors: Miller Melvin P.
Published: October 2009

Since we had hoped to be able to use the P=S frequency to monitor the progress of sulfur addition reactions, we undertook the present study to firmly establish the positions of that band in the spectra of compounds of interest. To be sure, assignment of a given band in the spectrum of a complex molecule to a particular localized motion is only an approximation. Nevertheless, we hoped that the spectra of isotopically substituted compounds might provide some information about the extent to which the P=S vibration could be considered to be an isolated motion. In addition we hoped that some insight could be gained into the nature of the interactions which stabilize the rotational isomers. To our knowledge, no 34S spectra of thionophosphate esters appear in the literature, except for those cited in conference proceedings,6 reported by us.
JCAMP-DX for Mass Spectrometry
Authors: Lampen Peter , Hillig Heinrich , Davies Antony N. , Linscheid Michael
Published: October 2009

JCAMP-DX has, for several years, been the standard form for the exchange of infrared spectral data. More recently JCAMP-DX protocols have been published for chemical structure data and for nuclear magnetic resonance spectroscopy. This publication presents a new JCAMP-DX data exchange protocol for mass spectrometry, covering the transport of single spectra, spectral series, and raw data files. The protocol can be implemented on any computer system and storage media. It is completely manufacturer independent. As with previous publications in this series, the aim is to provide reliable data transfer without loss of information regardless of the hardware or software involved. A comparison to the work on a binary protocol currently being carried out by the Analytical Instrument Association is also presented.
IR Emission Spectrum of Solid Materials under Periodic Heating: Modulated Emission Spectroscopy (MES)
Authors: Guillois O. , Nenner I. , Papoular R. , Reynaud C.
Published: October 2009

Prompted by the need to identify absolute values of IR absorptivities of high-opacity, refractory materials for astrophysical purposes, we have developed a new type of emission spectroscopy. This method makes use of a modulated radiation source of a common type and does not require that the sample material be thinned or be embedded in a matrix. Even very high absorptivities can be measured and then measured in situ as a function of temperature. The theory underlying the data treatment is developed and illustrated by applications to two materials of astrophysical interest. Limitations and possible improvements are discussed.
Description and Performance of a Fiber-Optic Confocal Fluorescence Spectrometer
Authors: Richards-Kortum Rebecca , Durkin Anthony , Zeng Jing
Published: October 2009

We describe a fiber-optic-based confocal fluorescence spectrometer for obtaining depth-resolved, attenuated fluorescence emission spectra with lateral resolution of several microns and depth resolution of tens of microns. The confocal optics of the spectrometer are small, inexpensive, and easy to construct and to interface to existing spectrometers. We compare the performance of this system to that of conventional fluorescence spectrometers for nonscattering homogeneous and inhomogeneous samples. We demonstrate that the confocal measurements readily provide information about the sample geometry and optical properties not available from nonconfocal measurements. Potential applications of the technique are discussed.
YO A2II1/2,3/2 Vibrational State Distributions Measured after the Excimer Laser Ablation of Y2O3 Using a Laser-Initiated Pulsed Discharge as a Probe
Authors: Fried Daniel , Kushida Toshimoto , Reck Gene P. , Rothe Erhard W.
Published: October 2009

The vibrational populations of the YO A2II- X2Σ system of YO were measured in the plasmas generated after the excimer laser ablation of Y2O3 in oxygen when both continuous and pulsed electric fields were applied. When an electric field is applied antiparallel to the direction of propagation of the ejected electrons, two luminous plumes appear, separated by several microseconds. The measured vibrational populations of the YO A2II- X2Σ system are different for each plume. The YO A2II populations were nonthermal in the first plume, representing emission from chemiluminescent reactive collisions in the plume after ablation. The second emission pulse, initiated by the discharge of a high-voltage capacitor, probes the ground-state YO in the plume via electron collisions. This pulsed electric field holds promise as a diagnostic probe of the ground-state species emitted in laser ablative processes.
Solvent Effects on Surface-Enhanced Raman Activity of Adsorbates on Colloidal Silver
Authors: Rupérez A. , Laserna J. J.
Published: October 2009

Surface-enhanced Raman spectrometry of a variety of drugs on colloidal silver is reported. Solvent effects on the Raman activity of adsorbates are discussed in terms of coadsorption and replacement kinetics at the silver surface. It is shown that the number of analytes amenable to SER spectrometry and the quality of the spectra can be improved by optimizing the solvent for the adsorbate under study. The influences of solvent on sensitivity, linear range of response, and shape of the calibration graph are discussed.
Can High-Pressure Raman Spectroscopy Be Simplified? A Microscale Optical-Fiber Capillary Cell for the Study of Supercritical Fluids
Authors: Howdle Steven M. , Stanley Keith , Popov Vladimir K. , Bagratashvili Viktor N.
Published: October 2009

This paper reports the design of a simple and inexpensive optical fiber capillary flow cell which is ideally suited to Raman spectroscopy and, in particular, the analysis of high-pressure supercritical fluid solutions. Light is delivered directly to the solution by use of optical fibers which run along the bore of the capillary. For maximum efficiency of light collection, the capillary is mounted directly onto and along the axis of the entrance slit of a dispersive Raman spectrometer. The Raman spectra of supercritical carbon dioxide (scCO2) solutions of gases (e.g., nitrogen and hydrogen), and solid solutes (e.g., naphthalene) are presented.
Determination of Total Chlorine in Chrysotile by X-ray Fluorescence Spectrometry
Authors: Zamojska Régina , Sharman Jeff , Cote Yvon , Jolicoeur Carmel
Published: October 2009

Energy-dispersive x-ray spectrometric methods have been developed for the determination of chlorine in asbestos (chrysotile) fibers. Chlorine, which is a minor constituent, is determined by a standard addition method from the ground fiber and by a standardless method in six different fibers. The lower limit of detection for a qualitative analysis and the lower limit of determination for a quantitative analysis of chlorine in the asbestos matrix are 40 ppm and 120 ppm, respectively. The water-soluble and acid-soluble chlorine have also been determined by ion-exchange chromatography and by a colorimetric method. The agreement of the three different methods is very good in all cases.
Raman Spectroscopic Investigation of the Physical State of para-Nitroaniline in Channels of the AIPO4-5 Molecular Sieve
Authors: Hill W. , Marlow F. , Kornatowski J.
Published: October 2009

The physical state of para-nitroaniline ( p-NA) adsorbed in the channels of AlPOj-5 molecular sieves has been investigated by means of Raman spectroscopy. The Raman spectra show that the p-NA molecules within the channels form either a phase of head-to-tail chains similar to that in the solid crystaline p-NA with a characteristic ω3 band at 1282 cm−1 or a second phase, which is characterized by the similarly strong band around 1295 cm−1. This second phase consists of weakly interacting p-NA molecules in a similar pseudo-quinonoidic state as molten p-NA. Despite the missing formation of solid-like chains, molecules in the second phase are also highly orientated. However, their mean nutation angle with respect to the crystal axis z is about 16°, and, thus, it is larger than that of the chains.
Identification of Breast Carcinomatous Tissue by Near-Infrared Reflectance Spectroscopy
Authors: Wallon Joëlle , Yan Shou He , Tong Jiashu , Meurens Marc , Haot Jules
Published: October 2009

NIR reflectance spectra of 110 cryostat sections of carcinomatous tissue and 114 cryostat sections of normal surrounding fibro-glandular tissue from 10 cases of breast cancer, identified by a classical pathology method, were scanned between 1100 and 2500 nm by a grating spectrometer in reflectance mode. Four wavelength intervals (1208–1242, 1746–1788, 2012–2048 and 2326–2368 nm) were found to be different for normal and carcinomatous tissues. In each interval, the second-derivative spectra of normal tissue showed a similar pattern with several characteristic peaks. In order to test the capacity of NIR spectroscopy in discriminating between normal and carcinomatous breast samples, 104 tissue sections from five additional cases were scanned prior to microscopic examination. The diagnostic prediction of NIR spectroscopy coincided exactly with the histology diagnosis for all the samples. Moreover, the presence of even a minute quantity of cancer infiltration can be detected by NIR spectroscopy, in total accordance with the microscopical observation. Therefore, the results of our experiments allow us to consider that NIR spectroscopy might become, with feasible improvements, an accurate, rapid, and reliable method for detecting breast cancer.
Ion Enhancement Effect of Laser-Enhanced Ionization Induced by One-Step Excitation and Two-Step Excitation
Authors: Su King-Do , Lin King-Chuen
Published: October 2009

The two-step laser-enhanced ionization (LEI) technique is believed to be more sensitive and selective in trace analysis than one-step LEI. As reported previously, for optimization of the two-step LEI configuration, factors involving laser intensity, transition probability of second-step excitation, collisional ionization rates, and transition linewidth should be taken into account. We have derived a simple theoretical model in relation to these parameters that is rough but suitable in practice for characterizing the ion yields enhanced by two-step LEI over one-step LEI. According to the model, each parameter affecting the ion enhancement has been systematically examined and compared to the theoretical evaluation. The findings of the relative ion enhancement as a function of each related parameter are consistent with the model prediction, except for the effect of transition linewidth, which is underestimated theoretically due to the difficulty of establishing the experimental conditions.
γ-Secretase: Successive Tripeptide and Tetrapeptide Release from the Transmembrane Domain of β-Carboxyl Terminal Fragment
Authors: Takami Mako , Nagashima Yu , Sano Yoshihisa , Ishihara Seiko , Morishima-Kawashima Maho , Funamoto Satoru , Ihara Yasuo
Published: October 2009

Amyloid β protein (Aβ), a pathogenic molecule associated with Alzheimer's disease, is produced by γ-secretase, which cleaves the β-carboxyl terminal fragment (βCTF) of β-amyloid precursor protein in the middle of its transmembrane domain. How the cleavage proceeds within the membrane has long been enigmatic. We hypothesized previously that βCTF is cleaved first at the membrane–cytoplasm boundary, producing two long Aβs, Aβ48and Aβ49, which are processed further by releasing three residues at each step to produce Aβ42and Aβ40, respectively. To test this hypothesis, we used liquid chromatography tandem mass spectrometry (LC-MS/MS) to quantify the specific tripeptides that are postulated to be released. Using CHAPSO (3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxyl-1-propanesulfonate)-reconstituted γ-secretase system, we confirmed that Aβ49is converted to Aβ43/40by successively releasing two or three tripeptides and that Aβ48is converted to Aβ42/38by successively releasing two tripeptides or these plus an additional tetrapeptide. Most unexpectedly, LC-MS/MS quantification revealed an induction period, 3–4 min, in the generation of peptides. When extrapolated, each time line for each tripeptide appears to intercept the same point on thex-axis. According to numerical simulation based on the successive reaction kinetics, the induction period exists. These results strongly suggest that Aβ is generated through the stepwise processing of βCTF by γ-secretase.
Bestrophin-1 Encodes for the Ca2+-Activated Anion Channel in Hippocampal Astrocytes
Authors: Park Hyungju , Oh Soo-Jin , Han Kyung-Seok , Woo Dong Ho , Park Hyekyung , Mannaioni Guido , Traynelis Stephen F. , Lee C. Justin
Published: October 2009

In mammalian brain, neurons and astrocytes are reported to express various chloride and anion channels, but the evidence for functional expression of Ca2+-activated anion channel (CAAC) and its molecular identity have been lacking. Here we report electrophysiological evidence for the CAAC expression and its molecular identity by mouseBestrophin 1(mBest1) in astrocytes of the mouse brain. Using Ca2+imaging and perforated-patch-clamp analysis, we demonstrate that astrocytes displayed an inward current at holding potential of −70 mV that was dependent on an increase in intracellular Ca2+after Gαq-coupled receptor activation. This current was mediated mostly by anions and was sensitive to well known anion channel blockers such as niflumic acid, 5-nitro-2(3-phenylpropylamino)-benzoic acid, and flufenamic acid. To find the molecular identity of the anion channel responsible for the CAAC current, we analyzed the expression of candidate genes and found that the mRNA for mousemBest1is predominantly expressed in acutely dissociated or cultured astrocytes. Whole-cell patch-clamp analysis using HEK293T cells heterologously expressing full-lengthmBest1showed a Ca2+-dependent current mediated by mBest1, with a complete impairment of the current by a putative pore mutation, W93C. Furthermore, mBest1-mediated CAAC from cultured astrocytes was significantly reduced by expression ofmBest1-specific short hairpin RNA (shRNA), suggesting that the CAAC is mediated by a channel encoded bymBest1. Finally, hippocampal CA1 astrocytes in hippocampal slice also showed mBest1-mediated CAAC because it was inhibited by mBest1-specific shRNA. Collectively, these data provide molecular evidence that the mBest1 channel is responsible for CAAC function in astrocytes.
Cycling Behavior and Memory Formation: Table 1.
Authors: Gerstner Jason R. , Lyons Lisa C. , Wright Kenneth P. , Loh Dawn H. , Rawashdeh Oliver , Eckel-Mahan Kristin L. , Roman Gregg W.
Published: October 2009

Circadian research has spent considerable effort in the determining clock output pathways, including identifying both physiological and behavioral processes that demonstrate significant time-of-day variation. Memory formation and consolidation represent notable processes shaped by endogenous circadian oscillators. To date, very few studies on memory mechanisms have considered potential confounding effects of time-of-day and the organism's innate activity cycles (e.g., nocturnal, diurnal, or crepuscular). The following studies highlight recent work describing this interactive role of circadian rhythms and memory formation, and were presented at a mini-symposium at the 2009 annual meeting of the Society for Neuroscience. The studies illustrate these time-of-day observations in a variety of behavioral paradigms and model organisms, including olfactory avoidance conditioning inDrosophila, long-term sensitization inAplysia, active-avoidance conditioning in Zebrafish, and classical fear conditioning in rodents, suggesting that the circadian influence on memory behavior is highly conserved across species. Evidence also exists for a conserved mechanistic relationship between specific cycling molecules and memory formation, and the extent to which proper circadian cycling of these molecules is necessary for optimal cognitive performance. Studies describe the involvement of the core clock geneperiod, as well as vasoactive intestinal peptide, melatonin, and the cAMP/MAPK (cAMP/mitogen-activated protein kinase) cascade. Finally, studies in humans describe evidence for alterations in cognitive performance based on an interaction between sleep–wake homeostasis and the internal circadian clock. Conservation of a functional relationship between circadian rhythms with learning and memory formation across species provides a critical framework for future analysis of molecular mechanisms underlying complex behavior.
The Biology of Memory: A Forty-Year Perspective
Authors: Kandel Eric R.
Published: October 2009

In the forty years since the Society for Neuroscience was founded, our understanding of the biology of memory has progressed dramatically. From a historical perspective, one can discern four distinct periods of growth in neurobiological research during that time. Here I use that chronology to chart a personalized and selective course through forty years of extraordinary advances in our understanding of the biology of memory storage.
Relationships between FSH, inhibin B, anti-Mullerian hormone, and testosterone during long-term treatment with the GnRH-agonist histrelin in patients with prostate cancer
Authors: Eldar-Geva Talia , Liberty Gad , Chertin Boris , Fridmans Alon , Farkas Amicur , Margalioth Ehud J , Spitz Irving M
Published: October 2009

Objectives

Medical castration with long-acting GnRH-agonist (GnRHa) is a well-established treatment for metastatic prostate cancer. Our aim was to explore the relationships between FSH, inhibin B, anti-Mullerian hormone (AMH), and testosterone during treatment with an implant releasing GnRHa.

Design

Analysis of hormone levels in frozen serum samples.

Methods

Ten patients aged 77±7 (means±s.e.m.) years with prostate cancer were treated with the GnRHa histrelin for at least a year. Two weeks prior to insertion and for 3–4 months following removal the patients were treated with the antiandrogen flutamide. Serum inhibin B, FSH, testosterone, and AMH levels were measured retrospectively.

Results

FSH, inhibin B, and testosterone increased during antiandrogen administration and levels fell after implant insertion. Four weeks post insertion, FSH gradually increased while inhibin B and testosterone remained fully suppressed. AMH levels did not change during antiandrogen treatment, but increased following implant insertion and remained elevated for the duration of implant use. Following removal, FSH and testosterone increased, inhibin B remained low, while AMH decreased.

Conclusions

The secondary increase in FSH following initial suppression with the implant is probably related to impaired inhibin B secretion. The lack of inhibin B response to the secondary increase in FSH suggests that long-term exposure of Sertoli-cells to GnRHa impairs their function. This effect appears to be selective since unlike inhibin B, AMH increased. In the absence of testosterone, FSH has a role in AMH regulation.
Towards High Energy Density 3D-integrated Lithium-ion Micro-batteries
Authors: Oudenhoven Jos F.M. , Baggetto Loïc , Niessen Rogier A.H. , Knoops Harm C.H , Donders Merijn , van Dongen Teus , de Croon Mart , Kessels Erwin , Notten Peter
Published: October 2009

To investigate the feasibility of a 3D integrated all-solid-state micro-battery, the deposition of several battery materials was investigated. Deposition techniques where used that are in principle able to deposit step conformally in 3D structures: ALD was used to create a conductive Pt current collector, and LPCVD was applied for the deposition of poly-silicon anodes and LiCoO2 cathodes.
The layers, initially deposited on planar substrates, showed the expected physical and electrochemical behavior and are in principle suitable for solid state micro-batteries.