bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectrographic Analysis of Tantalum and Tantalum Oxide
Authors: Laib Roger D.
Published: October 2009

Tantalum metal is analyzed for 12 impurity elements by using a carrier distillation technique with a dc arc. The metal is oxidized in a muffle oven at 900°C. The oxide is mixed with a special carrier made of silver metal, silver chloride, and barium fluoride. A set of standards is included on each plate, and the analytical curves are linear for the concentration range used. The coefficient of variation varies from 30 to 87%
Improved Spectrochemical Analysis of Alumina by Mineralized Calcination
Authors: Lemieux P. E.
Published: October 2009

Alumina-types present striking differences in physical properties, which have detrimental effects on accuracy of spectrochemical analysis. Calcination with a small amount of aluminium fluoride eliminates many of these differences The “mineralized calcination step” converts all samples to essentially alpha alumina of very similar monocrystal size, and subsequent grinding while mixing with graphite introduces still more uniformity This treatment is simple and can be carried out on a number of samples at the same time It provides significant improvement in both accuracy and precision. Details of the pre-treatment are presented along with analytical data to show the improvement.
A General Spectrochemical Method for Traces of Lead in Iron and Nickel Base Alloys
Authors: Davis C. M. , Anderson R. F.
Published: October 2009

A general spectrochemical method for determining trace amounts of lead in a variety of iron- and nickel-base alloys is presented The lead is concentrated by co-precipitation with strontium as sulfate The internal standaid, bismuth sulfate, is added to the dried precipitate The mixture is excited using the dc arc. The coefficient of variation at the 4 ppm level is 14%, and 13% at 40 ppm
Characterization of Hydroxyl Compounds Identification of Their 3,5-Dinitrobenzoate Esters by Infrared Spectroscopy
Authors: Douthit Robert C. , Garska Kenneth J. , Yarborough Victor A.
Published: October 2009

Standard methods for the identification of alcohols often produce questionable results. The infrared spectrum of a 3 5-dinitrobenzoate ester permits rapid identification of the original alcohol. Therefore, reference infrared spectra have been obtained for the 3,5-dinitrobenzoate derivatives of 24 alcohols containing from 1 to 22 carbon atoms The infrared spectra of these 3,5-dinitrobenzoate derivatives are unique; even closely related alcohols that differ only by one methylene group form 3,5-dinitrobenzoate esters, which often exhibit markedly different infrared spectra. Although the melting points of these derivatives may be close, the infrared spectra permit positive identification In qualitative analysis, infrared techniques can be used either alone or in conjunction with x-ray diffraction techniques.
Molecular Structure Studies of 1,1,1-Triethylhydrazinium Chloride
Authors: Harvey Mack C. , Kramm David E.
Published: October 2009

Infrared, nuclear magnetic resonance and ion exchange methods have been used to establish the molecular structure of 1,1,1-triethylhydrazimum chloride. Using stoichiometric ion exchange techniques, a general method for preparing 1,1,1-tnalkylhydrazinium salts has been developed and used to prepare compounds of the 1,1,1-tnethylhydrazimum cation and fourteen other anions. Infrared spectral studies on these compounds have shown that there is a strong hydrogen-bond between the -NH2 group and the anion and that the stretching-vibration frequency appears to be related to mass, charge, and geometry of the anion. Nuclear magnetic resonance and molecular weight studies on 1,1,1-tnethylhydrazinmm chloride show that the compound exists as a dimer when dissolved in chloroform. The molecule is partially dissociated when acetonitrile is used as a solvent
Absorption Spectral Studies of Complexes of 8-Aminoquinoline with Metal Halides
Authors: Coakley Mary P.
Published: October 2009

Ultraviolet measurements in potassium bromide disks of the 2:1 complexes of 8-aminoquinoline with the chlorides of Mg, Ni(II) and Pd(II), and the 1.1 complexes with the chlorides of Zn, Cd and Cu(II) show a shift toward shorter wavelengths from that of the 8-aminoquinohne in the 300 millimicron region. The extent of the shift is almost identical for the Mg, Zn, Cd, Ni(II) and Cu(II) chelates, indicating that the metals are equally effective in blocking the resonance between the amino group and the quinohne ring by the nitrogen-to-metal bond formation. The ultraviolet spectra of the complexes of 8-aminoquinoline in dioxane do reveal differences in the values of the long wavelength maxima. Absorption patterns in the 3 micron region reveal the expected decrease in the frequencies of the N-H stretching vibration on chelation.
Differential Infrared Spectroscopy of Chemically Modified Cottons
Authors: McCall Elizabeth R. , Miles Sylvia H. , Tripp Verne W. , O'Connor Robert T.
Published: October 2009

A technique for obtaining differential infrared absorption spectra of chemically modified cottons is described, and its value illustrated by selected examples. With KBr discs in a double-beam spectrophotometer, absorption bands common to unmodified and modified cottons can be reduced in intensity by placing equivalent quantities of cellulose in both beams The resulting spectrum facilitates identification of the molecular species introduced in making the derivative. The method is useful in obtaining spectra of the reaction products of cotton and intermolecular crosslinking agents at low degrees of addon Application of the method to cotton reacted with compounds of the dimethylol urea type and with other agents is described.
The Infrared Spectra of Some Chlorinated Hydrocarbons in the Cesium Bromide Region
Authors: Bolleter W. T.
Published: October 2009

The infrared spectra of 54 C1 to C4 chlorinated hydrocarbons in the cesium bromide region are presented Rough frequency correlations are seen for various structural features in the compounds studied However, these correlations are not sufficiently definitive for structure determination. Many of the compounds give unique absorption bands which would permit their detection and determination in the presence of very closely related compounds This is especially important in a mixture of compounds such as cis- and trans-1-chloro-1,3-butadiene where a determination of the ratio of the isomers is difficult in the rocksalt region.
Some Infrared Spectral Studies of Aliphatic Aldehydes in the 700–400 cm−1 Region
Authors: Pustinger J. V. , Katon J. E. , Bentley F. F.
Published: October 2009

The infrared spectra of thirteen aliphatic aldehydes of varying structure have been recorded and analyzed in the range of 700–400 cm−1 The structural configuration adjacent to the carbonyl group was found to affect the observed spectra in a specific manner It thus appears possible to differentiate α-branched and non-α-branched aliphatic aldehydes from their infrared spectra in this region.
Infrared Spectroscopy by Attenuated Total Reflection
Authors: Sherman Bennett
Published: October 2009

A review is given of the attenuated total reflection method in infrared spectroscopy Some spectra of biological material are included to illustrate its value in the biomedical field
Proton Magnetic Resonance of Some Cyclopropane Derivatives
Authors: Abrahams Allan , Wiberley Stephen E. , Nachod Frederick C.
Published: October 2009

The proton magnetic resonance of fifteen cyclopropane derivatives were studied In each case the substituent groups were on only one of the ring carbons The chemical shifts of the four protons on the remaining two carbons were determined to range from δ values of 0 40 to 1.62 ppm, using as an internal reference tetramethyl silane (with δ = 0 00). Direct evidence on the relative electron withdrawing ability of the substituent groups is presented
The Determination of Certain Noble Metals in Solution by Means of X-Ray Fluorescence Spectroscopy. 1. The Determination of Platinum, Gold, and Iridium
Authors: Strasheim A. , Wybenga F. T.
Published: October 2009

X-ray fluorescence methods are described for the accurate quantitative determination of platinum, gold, and iridium in solution. For the platinum determinations, it is shown how corrections for interelement effects can be applied using background intensities to calculate absorption effects. In an alternative method for the platinum determination, zinc was found to be a satisfactory internal standard For the determination of gold and iridium, platinum is used as variable internal standard. Coefficients of variation of less than one % and from one to three % were obtained for platinum and for gold and iridium determinations respectively
Infrared Analysis of p-Quinone Dioxime Dibenzoate and its Determination in Butyl Rubber Formulations
Authors: Burley R. A.
Published: October 2009

The dibenzoate ester of p-quinone dioxime (DBPQD) is used as a curing agent for certain butyl rubber formulations Infrared methods of analysis are described for the following determinations: 1) free p-quinone dioxime in DBPQD and its dispersions; 2) DBPQD in dispersions with rubber processing oil, wax, etc; and 3) DBPQD in uncured butyl rubber. Applications of the analytical methods are discussed
Infrared Examination of Micro Samples—Application of a Specular Reflectance System
Authors: Sloane H. J. , Johns T. , Ulrich W. F. , Cadman W. J.
Published: October 2009

A specular reflectance system for the infrared analysis of micro size samples is described and its advantages and limitations compared to other micro infrared techniques. Samples are mounted on small metal mirrors which reflect the light beam back through the sample. A transmission spectrum of the sample is thereby obtained but the effective path length is twice that of the actual thickness. A given absorption band therefore has twice the absorbance obtained by conventional transmission measurements The system has been applied mainly to gas chromatographic fractions but should be suitable to a variety of other analyses. Major limitations include a “stray light” artifact, polymorphism effects, and difficulties in achieving sample uniformity.
Ultraviolet Determination of Additives in Polyethylene
Authors: Luongo J. P.
Published: October 2009

A method for determining a large number of additives such as antioxidants, expanding agents, etc in polyethylene is discussed. The method consists of compression molding a clear film of polyethylene containing the additive. From this film the ultraviolet absorbance of the additive can be measured and the concentration calculated. It is possible to determine quantitatively most additives in the 0 002 to 1 0 per cent range. An application of the technique is described, and the advantages and limitations of the method are discussed.
The Controlled Atmosphere Direct Current Arc for the Quantitative Determination of Trace Metals in Organics
Authors: Nash D. L.
Published: October 2009

A method has been developed to permit the quantitative determination of trace metals in polypropylene and other organic materials in which the total ash content ranges from 0.10 per cent to less than 0.001 per cent by weight. A small sample of the material is ashed directly in the electrode. A fixed amount of germanium internal standard solution is added to the electrode and dried Standards are prepared by adding weighed amounts of a plastic dispersion containing known amounts of the elements to be determined to specially prepared electrodes. Using a controlled atmosphere chamber the prepared electrodes are excited with a dc arc in an atmosphere of argon and oxygen and the spectra recorded photographically.
Mercury-204 Determination by Emission Spectroscopy
Authors: Smith F. M.
Published: October 2009

The determination of mercury-204 was made by using the isotope shift of the 3984 A mercury line excited by electrodeless discharge. Densitometric traces were made from film recordings of the 3984 A line and the areas under the component peaks were determined. Ratios of each of these areas to the sum of the areas from all the line components are plotted against the isotope concentration to produce a working curve. The coefficient of variation for this method is approximately 11 percent The time required for a single determination (after fabrication of the discharge lamp) is about two hours.
Isotope Structure of Uranium Line U I 5027.4 A and its Use for Isotope Analysis
Authors: Berthelot Ch. A. , Lauer K. F.
Published: October 2009

Experiments on the isotope shift of U233, U236, U235, U234, and U233 in the uranium emission line U I 5027.4 A are made with the photoelectric interferometer Hypeac. The ratios U235 + U234/U233 and U233 + U231/U238 can be determined with the Automatic Electronic Integrator. The possibility of interference between the lines U235 5027 295 A and U236 5027.338 A is discussed
Dual Grinding and X-Ray Analysis of All Major Oxides in Rocks to Obtain True Composition
Authors: Volborth A.
Published: October 2009

Contamination introduced by grinding methods is determined quantitatively with high precision and accuracy by the x-ray spectrographic analysis of all major oxides in rocks. This is done by performing two complete analyses of rock powders of identical origin but ground by different grinding media. Original composition of uncrushed rock is computed on the basis of these two analyses. This method is feasible because of the speed of the x-ray analysis. It is accurate because the same matrix with only slight compositional changes due to contamination is used. Data are given on six volcanic rocks analyzed for Si, Al, Ti, Fe, Mn, Mg, Ca, K, and Na.
Controlled Atmosphere Excitation in Non-Enclosed Spark Stands
Authors: Boyd B. R. , Goldblatt A.
Published: October 2009

The use of atmospheres for sample excitation has assumed increasing importance in emission spectrochemical analysis. This emphasis has resulted in a study of electrode jet enclosures designed to adapt existing stands for spark excitation. Special configurations of enclosures are required to achieve satisfactory point-to-plane analysis. Data will be presented for high voltage spark and spark-initiated condensed arc discharges and for the conditions required to achieve the “energetic burn” that is essential for improved sensitivity and accuracy in the analysis of steel, lead, and other alloys.
Identification of Trace Amounts of Organophosphorus Pesticides by Frustrated Multiple Internal Reflectance Spectroscopy
Authors: Hermann T. S.
Published: October 2009

The technique of frustrated multiple internal reflectance is employed for the identification of trace amounts of organophosphorus pesticides eluted from column, paper, or thin-layer chromatograms. The high sensitivity, the ease of sample manipulation and the applicability to solid and liquid samples give the FMIR technique noteworthy advantages over transmission techniques.
Raman Spectroscopic Identification of Calcium-Oxalate-Type Kidney Stone
Authors: Kodati Venkata Ramana , Tomasi Gordon E. , Turumin Jacob L. , Tu Anthony T.
Published: October 2009

The Raman scattering technique is used to obtain spectra from four kidney stones. An argon-ion laser (514.5 nm) is focused directly on the surface of the stones. Three stones were known to be composed mainly of hydrates of calcium oxalate, CaC2O4·H2O, and CaC2O4·2H2O. The scattered Raman shift is examined and compared with that of the standard hydrates. Two stones have spectra almost identical to that of calcium oxalate monohydrate. The characteristic bands at 1465 and 1492 cm−1 are easily observed. The spectrum from the third stone shows a band at 1477 cm−1 characteristic of calcium oxalate dihydrate, but it also shows weaker bands at 1465 and 1492 cm−1, which are observed in spectra of calcium oxalate monohydrate. It is concluded that the first two stones are primarily composed of CaC2O4·H2O, while the third stone includes both hydrates in its structure. The fourth stone, from a Russian woman, shows bands at 627, 998, 1038, 1405, 1465, and 1492 cm−1. The first few bands are characteristic of uric acid, while the 1465- and 1492-cm−1 bands indicate calcium oxalate monohydrate. It is possible not only to identify these two components but also to show their relative distribution within the stone.
Electron Temperature and Density Profiles of Excimer Laser-Induced Plasmas
Authors: Grant Kenneth J. , Paul George L.
Published: October 2009

Results are presented of a study of the plasma induced by the irradiation of a steel target by an excimer laser (308 nm, 28 ns, 40 mJ/pulse). Plasmas were formed in atmospheres of air, argon, nitrogen, and helium, at pressures from 0.5 Torr to 760 Torr. The maximum spectral intensity and line-to-background ratio occur in an atmosphere of argon at a pressure of 50 Torr. Spectroscopic techniques were used to measure time-integrated electron temperature and density profiles of the plasmas.
High-Pressure Micro-Raman Spectra of Potassium Chromate(VI) and Potassium Tungstate(VI)
Authors: Huang Yining , Butler Ian S.
Published: October 2009

The effects of high external pressures on the micro-Raman spectra of potassium chromate, K2CrO4, and potassium tungstate, K2WO4, have been investigated for pressures approaching 45 kbar. There is no evidence for a pressure-induced phase transition in the chromate, but there is clearly such a transition at ∼13 kbar in the tungstate. The pressure sensitivities of the principal bands observed in the spectra of the two salts have been determined. The values obtained are comparable to those reported for simple spinels and somewhat larger than those for scheelites.
Photoacoustic Measurements of Agriculturally Interesting Gases and Detection of C2H4 below the PPB Level
Authors: Harren F. J. M. , Reuss J. , Woltering E. J. , Bicanic D. D.
Published: October 2009

We present a laser photoacoustic system which is able to detect a minimum absorption coefficient of 7.1 × 10−10 cm−1 corresponding to a concentration of 20 parts per trillion of C2H4 in air. Improvements made to achieve this sensitivity are reported, and this low limit is applied to the detection of the C2H4 emission of a single orchid flower after emasculation. In addition, the absorption coefficients and detection limits of the following agriculturally interesting gases are measured: ozone, hydrogen sulphide, 1,2 dibromoethane, and ethylacetate.
Fourier Transform Infrared Spectrometry Coupled with Cryogenic Trapping for the Study of Laser-Desorbed Species
Authors: Brown R. S. , Gilfrich N. L.
Published: October 2009

The feasibility of using cryogenic trapping techniques combined with infrared spectrometry to study the products of laser desorption is demonstrated. A prototype system for cryogenically trapping transient species desorbed during the laser desorption process is described. The products produced by a high-power pulsed carbon dioxide laser (10.6 μm) are cryogenically trapped on an infrared transmitting substrate attached directly to a closed-cycle helium refrigerated coldhead via an OFHC copper holder whose temperature is maintained at approximately 18 K. The sample is then rotated into the beam of a Fourier transform infrared (FT-IR) spectrometer, and conventional transmission spectra are obtained. System performance is described, and representative results obtained for a sample of rhodamine B dye and a polyethylene glycol polymer are presented. The rhodamine B dye is shown to significantly fragment as a result of laser desorption (consistent with the known behavior of the ionic products studied by laser desorption mass spectrometry), while the polyethylene glycol sample produces almost exclusively intact neutral species (also in agreement with laser desorption mass spectrometry results).
Solvent-Induced Nitrile Frequency Shifts: Acetonitrile and Benzonitrile
Authors: Nyquist R. A.
Published: October 2009

The C≡N stretching frequency, vC≡N, is affected by change in the solvent and also by change in concentration in the same solvent. In the case of acetonitrile, vC≡N is in Fermi resonance with the combination tone (δsym. CH3 + vC-C), and the degree of Fermi resonance interaction changes with change in the solvent. With the exception of dimethyl sulfoxide, unperturbed vC≡N for acetonitrile exhibits a pseudo-linear correlation with the acceptor number of the solvent.
Compressibilities of TbVO4 and DyVO4 Calculated from Spectroscopic Data
Authors: Chen G. , Haire R. G. , Peterson J. R.
Published: October 2009

The compressibilities of TbVO4 and DyVO4 were estimated indirectly from the pressure dependence of the Raman stretching frequencies of the vanadium-oxygen (V-O) bonds, v1( Ag), through an empirical correlation between v1( Ag) and the corresponding bond lengths. Volume compressibilities of 6.71 × 10−3 GPa−1 (bulk modulus 149 GPa) and 6.23 × 10−3 GPa−1 (bulk modulus 160 GPa) were derived for TbVO4 and DyVO4, respectively. This approach provides a straightforward method to estimate the compressibility and equation of state (EOS) of crystals via Raman spectroscopic measurements.
Determination of Temperature and Composition of Phosphosilicate Glass Thin Films from Infrared Emission Spectral Data
Authors: Wangmaneerat B. , Niemczyk T. M. , Haaland D. M.
Published: October 2009

Multivariate calibration methods were combined with full-spectrum IR emission data to determine the temperature and phosphorus (P) content of phosphosilicate glass (PSG) thin films on silicon wafers. The 12 PSG calibration samples varied in phosphorus content across the range of 1 to 6 wt %, and sample temperatures ranged from 119 to 225°C. The multivariate partial least-squares (PLS) algorithm was applied to both single-beam and emittance spectral data over the range of 450 to 1600 cm−1. The predictive abilities of the PLS models were obtained from the standard errors of prediction (SEP) calculated with cross-validation procedures. The cross-validated SEPs were 1.9°C for temperature determination and 0.13 wt % for P content. These SEPs were limited by the temperature controller for temperature determination and by the reference method for P determination. Full-spectrum multivariate calibration methods have been shown to be capable of precise and accurate temperature measurements in the presence of variations in sample emittances due to concentration differences. These results demonstrate the power of multivariate calibration for use in multiwavelength pyrometry. These techniques also demonstrate the potential to perform in situ, real-time process monitoring and precise temperature measurement during the deposition of thin dielectric films on silicon wafers.
Raman Microprobe Study of Inclusions in Glazes on Porcelain Dishes
Authors: Buerhop C. , Condrate R. A. , Moertel H. , Hapanowicz R. P.
Published: October 2009

Porcelain glaze defects can originate on cups and dishes during fast-firing processes due to formation of bubbles. Raman microprobe techniques have been used to analyze the gas contents of such bubbles along with determining the structural nature of solid inclusions found on the surface of or near the bubbles. Spectral data clearly indicate that the gas contents of these bubbles contain atmospheres comparable to air, along with possibly excess carbon dioxide, depending upon firing conditions. Investigated solid inclusions contain α-quartz and/or α-cristo-balite.
Studies of Multichannel Photothermal Refraction for the Measurement of Absolute Absorptivity
Authors: Klatt Leon N.
Published: October 2009

Multichannel crossed-beam photothermal refraction experiments have been performed. Iron(II)-phenanthroline in methanol was the test solute. The response as a function of concentration exhibited a nonlinear relationship, which does not agree with the current theoretical description of the phenomena. Although photophysical and photochemical processes were not totally eliminated as possible causes of the nonlinear concentration response, arguments are presented which indicate, for the experimental conditions employed in this study, that these processes are negligible. It is proposed that the heat transfer model must be modified to include refractive index gradients in both the radial and axial coordinates of the pump laser beam.
Development of a HeCd Laser-Based Fluorescence Detector for Analysis of Derivatized Biogenic Amines
Authors: Bostick J. M. , Strojek J. W. , Metcalf T. , Kuwana T.
Published: October 2009

The development of a highly sensitive laser-induced fluorescence (LIF) detector for HPLC is described. It was specifically designed to monitor the fluorescence emitted from biogenic amines which were derivatized by naphthalenedicarboxaldehyde (NDA) in the presence of cyanide ion. The product of the amine derivatization, cyanobenz[f]isoindole (CBI), absorbs radiation at the output wavelength of the HeCd laser (441.6 nm). Optimization of detector sensitivity included evaluation of both optical components and cell configurations. A laser dye, coumarin 7, served as the test analyte because its native spectral properties coincided with those of the CBI-amine adducts and because no derivatization step was required for each injection. A limit of detection (LOD) on the order of 2 × 10−12 M was reproducibly observed.
Infrared Emission Spectroscopy of Some Sulfate Minerals
Authors: Vassallo A. M. , Finnie K. S.
Published: October 2009

Infrared emission spectroscopy has been used to study the phase transformations of gypsum, thenardite, glauberite, and anhydrite between the temperatures of SO and 1400°C. It is shown that emission spectroscopy can be used to monitor these changes in situ and that metastable forms and reversible transformations are easily detected.
Coupling of LC and FT-IR: Impurity Profiling of Testosterone Undecanoate
Authors: Somsen G. W. , Gooijer C. , Brinkman U. A. Th. , Velthorst N. H. , Visser T.
Published: October 2009

Reversed-phase liquid chromatography (RP-LC) was coupled to Fourier transform infrared spectrometry (FT-IR) with the use of a spray jet assembly to eliminate the solvent and to deposit the effluent on zinc selenide. The usefulness of the LC/FT-IR system in impurity profiling is demonstrated for the steroid drug testosterone undecanoate (TU). FT-IR transmission spectra of components of the steroid sample separated by LC are identified directly by library search or are interpreted to yield structural information. The study also shows the occasional similarity of the spectra of testosterone enanthate (TE) and testosterone decanoate (TD), two possible impurities of TU. This phenomenon, which can hinder identification, is attributed to the fact that TE and TD can both be either in a crystalline or in an amorphous state.
GC/FT-IR Determination of the Relative Configuration of Spiro [2.n] Methylenecyclopropyl Carbinols Diastereoisomeric Pairs
Authors: Afshari M. , Guiliano M. , Leandri G. , Monti H.
Published: October 2009

The reaction of l-methylene-2-trimethylsilyl spiro[2.n] alkanes with aldehydes under almost neutral conditions using tetrabutylammonium fluoride is consistent with 80% of diastereoisomeric pairs of spiromethylene cyclopropyl carbinols. This study elucidates the stereochemistry of these alcohols using the GC/FT-IR technique for inseparable mixtures and FT-IR dilution technique for a separable pair.
Examining the Decomposition of Ethylene-Vinyl Acetate Copolymers Using TG/GC/IR
Authors: McGrattan Brian J.
Published: October 2009

With a combination of information from TG/IR and GC/IR measurements of the trapped gases, characterization of complex polymer decompositions can be made. In this paper, the thermally induced breakdown of ethylene-vinyl acetate (EVA) copolymers was studied. Results show that EVA undergoes a two-step decomposition: an acetate pyrolysis of the copolymer leaving a polyunsaturated linear hydrocarbon, followed by the breakdown of the hydrocarbon backbone to produce a large number of straight-chain hydrocarbon products.
Optimization of a Fluorescence Detection System for the Characterization of Solids
Authors: Downare Taggart D. , Mullins Oliver C. , Wu Xu
Published: October 2009

The optimization of a robust fluorescence detection system is described in which both scattered excitation light and collected fluorescence emission from rock, core, or cutting samples are guided by optical fibers. Analysis of solids poses increased difficulties compared to the extensively studied analysis of liquids; large and variable scattered light can lead to substantial reduction of the system dynamic range and to significant optical noise without proper rejection of the scattered source light. In addition, optical component fluorescence must be minimized; optimization and final optical component selections were based upon the system throughput as well as the system dynamic range. The optimized design was found by analysis of the individual system components—specifically, the source, launch objectives, fiber optics, output collimation optics, and filters. A system dynamic range of 5.1 optical density was achieved, and system performance was demonstrated with fluorescence yield measurements on a variety of solid samples.
Optical-Fiber Raman Probe with Low Background Interference by Spatial Optimization
Authors: Ma Jiaying , Li Ying-Sing
Published: October 2009

A Raman probe was set up with optical fibers and a graded refractive index (GRIN) lens. It was found that the Raman background arising from optical fiber was spatially dependent, while normal Raman (NR) scattering, surface-enhanced Raman scattering (SERS), and surface-enhanced resonance Raman scattering (SERRS) were spatially independent. Spatial optimization was carried out to minimize the background interference of the optical fiber Raman probe with the use of benzoic acid as a test sample. The best configuration of the probe could also be applied to both SERS and SERRS. SER spectra of p-nitrophenol (1.0 × 10−3 M) and SERR spectra of methyl red (1.0 × 10−6 M) were obtained with the use of this probe to check its performance.
Characterization of Surface Orientation in Poly(Ethylene Terephthalate) by Front-Surface Reflection Infrared Spectroscopy
Authors: Cole K. C. , Guèvremont J. , Ajji A. , Dumoulin M. M.
Published: October 2009

The use of front-surface specular reflection FT-IR spectroscopy to characterize surface orientation in thick samples of poly(ethylene terephthalate) (PET) has been investigated. It has been shown that, even for samples whose surface uniformity is less than perfect, absorption index spectra of excellent quality are obtained from the Kramers-Kronig transformation. These spectra provide detailed information, both qualitative and quantitative, on the molecular conformation and orientation of the polymer. Of particular interest are the strongly absorbing bands such as the carbonyl and ester peaks, which are generally saturated in transmission spectra. The reflection technique opens up the possibility of obtaining new information on conformational changes and orientation in PET through a detailed study of these peaks.
Error Analysis of Simple Algorithms for Determining Fluorescence Lifetimes in Ultradilute Dye Solutions
Authors: Soper Steven A. , Legendre Benjamin L.
Published: October 2009

We have evaluated the use of two simple algorithms for determining the decay parameters describing a single exponential process for dyes with nanosecond and subnanosecond fluorescence lifetimes in the limit of low concentrations and high backgrounds from scattered photons generated by the solvent using experimental and Monte Carlo simulation results. These algorithms, the maximum likelihood estimator (MLE) and the rapid lifetime determination (RLD), are computationally easy to perform, allowing the evaluation of large amounts of data quickly and efficiently. The MLE and RLD methods were used to calculate the fluorescence lifetimes of three near-IR dyes with lifetimes spanning the range of 0.57 ns to 1.12 ns. For low-concentration conditions and high background-to-fluorescence ratios, the MLE method resulted in larger errors when compared to RLD, although both methods yielded comparable standard deviations. However, when the interval over which the lifetime was calculated within the decay profile was shifted to latter times in order to reduce the amount of scattered photons included in the calculation, significant improvements in the accuracy were observed with the use of MLE. Shifting the start channel of the calculation to latter time channels within the decay profile did not affect the lifetime with the use of RLD. Inclusion of large amounts of scattering photons was found to bias the calculated lifetime to lower values, reducing the accuracy of the determination. The relative standard deviations for MLE and RLD were found to be approximately 2–3% at a background-to-fluorescence ratio of 0.5. The absolute relative error in the methods at the 0.50 background-to-fluorescence ratio ranged from 14 to 27% for MLE and 8 to 18% for the RLD method when the calculation was initiated at t = 0. This error was found to decrease to < 1% with the use of MLE when the calculation was initiated at t ≈ 100 ps.
Application of an Optical Beam Condenser for UV-Vis Spectral Studies on Monoclinic LnPO4 Single Crystals
Authors: Mullica D. F. , Wilson G. A. , Sappenfield E. L.
Published: October 2009

The application of an optical beam condenser was made for the purpose of measuring Judd-Ofelt intensity parameters, τλ on single crystals of monoclinic lanthanide orthophosphates, LnPO4. Intensity parameters were calculated from absorbance data obtained with the beam condenser on crystals having cross sections and pathlengths in the range of 3.0 to 5.0 mm2 and 0.4 to 0.8 mm, respectively. Interpretation of the results related to the environment of the lanthanide ion as well as the crystal structure is presented.
Design and Application of a New Reactor for in Situ Infrared Spectroscopic Investigations of Heterogeneously Catalyzed Reactions
Authors: Mirth Gabriele , Eder Florian , Lercher Johannes A.
Published: October 2009

A design of a metal reactor equipped with gas in- and outlet tubings and IR transparent windows is described. The IR cell approximates a wellstirred tank reactor and is suited for in situ kinetic investigations of catalytic reactions. While the catalyst, in contact with the reactants and products, is analyzed in situ by means of time-resolved FT-IR spectroscopy, the effluent gas stream is analyzed by gas chromatography mass spectroscopy. The reactor operates at temperatures up to 870 K; for applications of temperature-programmed desorption/reaction, linear heating rates between 1 and 20 K/min can be realized. Examples for applications are given.
Conformer Analysis Study of 1,2-Diiodotetrafluoroethane by Gas Chromatography/Fourier Transform Infrared Spectroscopy
Authors: Liang J. , Drake D. , Roselius M.
Published: October 2009

In this paper, the measurement of the energy difference between the rotational conformers of 1–2–diiodotetrafluoroethane by GC/FT-IR spectroscopy is demonstrated for the first time. The Δ H° obtained is lower than the value reported from the use of the neat vapor-phase method. The difference between the values may be attributed to solvent and adsorption effects.
XeCl Excimer Laser-Induced Shock Wave Plasma and its Application to Emission Spectrochemical Analysis
Authors: Kagawa K. , Kawai K. , Tani M. , Kobayashi T.
Published: October 2009

A XeCl excimer laser (20 ns, 15–70 mJ) has been focused on a Zn plate in surrounding gas at low pressures (100–1500 Pa). The characteristics of the resultant plasma are examined with the use of a unique time-resolved spectroscopic method. A density jump in the distribution of Zn atoms is clearly observed, which indicates the generation of a shock wave. Furthermore, it is proved that the relationships among the displacement length of the front of the emission of the Zn neutral emission line, the pressure of the ambient gas, and the energy of the laser pulse are in good agreement with the theoretical result for a blast wave explosion. An application is also presented to show that the plasma induced by a blast wave is excellent as a light source for emission spectrochemical analysis because of its very low background emission intensity.
Characterization and Expression of Netrin-1 and Its Receptors UNC5B and DCC in Human Placenta
Authors: Dakouane-Giudicelli Mbarka , Duboucher Christophe , Fortemps Joanne , Missey-Kolb Héliane , Brulé Danièle , Giudicelli Yves , de Mazancourt Philippe
Published: October 2009

Netrins are a family of proteins that mediate axonal guidance in the central nervous system (CNS). In addition to the CNS, netrins are involved in cell adhesion, motility, proliferation, differentiation, and survival. Because these processes occur in the placenta, we raised the question of whether netrin-1 is expressed by placental cells during development. In the present study, we analyzed the spatial and temporal distribution of netrin-1 and its two receptors, DCC (deleted in colorectal cancer) and UNC5B (uncoordinated-5 homolog) in human placenta using RT-PCR, Western blotting, and immunohistochemistry analysis. We demonstrated the presence of the proteins and transcripts of netrin-1 and its receptors in placenta and cytotrophoblasts. Furthermore, using immunohistochemistry, we localized endogenous netrin-1 protein staining to villous and extravillous cytotrophoblasts, and secreted netrin-1 outside the syncytiotrophoblasts. The DCC receptor was localized to syncytiotrophoblasts and invasive extravillous cytotrophoblasts during the first trimester and at term. On the other hand, the UNC5B receptor was localized to villous and extravillous cytotrophoblasts proximal to anchoring areas during the first trimester. At term, UNC5B was observed in decidual cells and weakly in extravillous cells. The discrete pattern of netrin-1 and netrin-1 receptor distribution suggested that netrin-1 protein functions might vary with its localization in the placenta and probably with time of gestation.
Signaling Cascade of Diacylglycerol Kinase β in the Pituitary Intermediate Lobe: Dopamine D2 Receptor/Phospholipase Cβ4/Diacylglycerol Kinase β/Protein Kinase Cα
Authors: Hozumi Yasukazu , Watanabe Masahiko , Goto Kaoru
Published: October 2009

The pituitary gland dynamically changes its hormone output under various pathophysiological conditions. One of the pathways implicated in the regulatory mechanism of this gland is a dopaminergic system that operates the phosphoinositide (PI) cycle to transmit downstream signal through second messengers. We have previously shown that diacylglycerol kinase β (DGKβ) is coexpressed with dopamine D1 and D2 receptors in medium spiny neurons of the striatum, suggesting a plausible implication of DGKβ in dopaminergic transmission. However, it remains elusive whether DGKβ is involved in the dopaminergic system in the pituitary gland. The aim of this study is to investigate the expression and localization of DGK in the pituitary gland, together with the molecular components involved in the PI signaling cascade, including dopamine receptors, phospholipase C (PLC), and a major downstream molecule, protein kinase C (PKC). Here we show that DGKβ and the dopamine D2 receptor are coexpressed in the intermediate lobe and localize to the plasma membrane side by side. In addition, we reveal that PLCβ4 and PKCα are the subtypes expressed in the intermediate lobe among those families. These findings will substantiate and further extend our understanding of the molecular-anatomical pathway of PI signaling and the functional roles of DGK in the pituitary intermediate lobe.
The Maturation of Oocyte Follicular Epithelium of Podarcis s. sicula Is Promoted by d-Aspartic Acid
Authors: Raucci Franca , Di Fiore Maria Maddalena
Published: October 2009

We investigated whether the maturation of oocyte follicular epithelium of lizard is affected by d-aspartic acid (d-Asp). Our results demonstrated that d-Asp is endogenously present in the oocytes, and its distribution varies during the reproductive cycle and following intraperitoneal administration. At previtellogenesis, it is observed in the cytoplasm and nucleus of pyriform cells, in intermediate cells, in some small cells of the granulosa, in the ooplasm, and in some thecal elements. At vitellogenesis, d-Asp is localized in the proximity of the zona pellucida, in the theca, and in the ooplasm. Injected d-Asp is mainly captured by pyriform cells and ooplasm of previtellogenic oocytes, but a moderate accumulation is evident in the cytoplasm of some small granulosa cells and in the theca. d-Asp also increases the ovarian and plasmatic levels of 17β-estradiol and decreases those of testosterone. As a direct and/or indirect consequence of d-Asp, previtellogenic oocytes grow up and mature, resulting in a higher accumulation of carbohydrates in the granulosa, zona pellucida, and ooplasm, but also a reduction in the thickness of the granulosa layer and an increase of the theca stratum. Taken together, our results show that d-Asp may be related to the synchrony of reproduction, either enhancing the growth and maturation of follicular epithelium or influencing its endocrine functions.
Fas/Fas Ligand–mediated Apoptosis in Different Cell Lineages and Functional Compartments of Human Lymph Nodes
Authors: Kokkonen Tuomo S. , Karttunen Tuomo J.
Published: October 2009

We have optimized an immunohistochemical double-staining method combining immunohistochemical lymphocyte lineage marker detection and apoptosis detection with terminal deoxyribonucleotidyl transferase–mediated dUTP nick end labeling. The method was used to trace Fas-mediated apoptosis in human reactive lymph nodes according to cell lineage and anatomical location. In addition to Fas, we also studied the expression of Fas ligand (FasL), CD3, CD20, CD19, CD23, and CD68 of apoptotic cells. The presence of simultaneous Fas and FasL positivity indicated involvement of activation-induced death in the induction of paracortical apoptosis. FasL expression in the high endothelial venules might be an inductor of apoptosis of Fas-positive lymphoid cells. In addition to B-lymphocyte apoptosis in the germinal centers, there was often a high apoptosis rate of CD23-expressing follicular dendritic cells. In summary, our double-staining method provides valuable new information about the occurrence and mechanisms of apoptosis of different immune cell types in the lymph node compartments. Among other things, we present support for the importance of Fas/FasL–mediated apoptosis in lymph node homeostasis.
Tissue Distribution of Murine Muc19/Smgc Gene Products
Authors: Das Biswadip , Cash Melanie N. , Hand Arthur R. , Shivazad Armin , Grieshaber Scott S. , Robinson Bently , Culp David J.
Published: October 2009

The recently identified gene Muc19/Smgc encodes two diverse splice variants, Smgc (submandibular gland protein C) and Muc19 (mucin 19). Muc19 is a member of the large gel-forming mucin family and is an exocrine product of sublingual mucous salivary glands in mice. SMGC is a transiently expressed secretion product of developing rodent sub-mandibular and sublingual glands. Little is known about the expression of Muc19/Smgc gene products in other murine salivary and non-salivary tissues containing the mucous cell phenotype. Muc19 expression was therefore initially assessed by RT-PCR and immunohistochemistry. As a complementary approach, we developed a knockin mouse model, Muc19-EGFP, in which mice express a fusion protein containing the first 69 residues of Muc19 followed by enhanced green fluorescent protein (EGFP) as a marker of Muc19 expression. Results from both approaches are consistent, with preferential Muc19 expression in salivary major and minor mucous glands as well as submucosal glands of the tracheolarynx and bulbourethral glands. Evidence also indicates that individual mucous cells of minor salivary and bulbourethral glands produce another gel-forming mucin in addition to Muc19. We further find tissue expression of full-length Smgc transcripts, which encode for SMGC, and are restricted to neonatal tracheolarynx and all salivary tissues.
Inhibitor κB Kinase β Deficiency in Primary Nociceptive Neurons Increases TRP Channel Sensitivity
Authors: Bockhart Vanessa , Constantin Cristina Elena , Häussler Annett , Wijnvoord Nina , Kanngiesser Maike , Myrczek Thekla , Pickert Geethanjali , Popp Laura , Sobotzik Jürgen-Markus , Pasparakis Manolis , Kuner Rohini , Geisslinger Gerd , Schultz Christian , Kress Michaela , Tegeder Irmgard
Published: October 2009

Inhibitor κB kinase (IKK) regulates the activity of the transcription factor nuclear factor-κ B that normally protects neurons against excitotoxicity. Constitutively active IKK is enriched at axon initial segments and nodes of Ranvier (NR). We used mice with a Cre–loxP-mediated specific deletion of IKKβ in sensory neurons of the dorsal root ganglion (SNS–IKKβ−/−) to evaluate whether IKK plays a role in sensory neuron excitability and nociception. We observed increased sensitivity to mechanical, cold, noxious heat and chemical stimulation inSNS–IKKβ−/−mice, with normal proprioceptive and motor functions as revealed by gait analysis. This was associated with increased calcium influx and increased inward currents in small- and medium-sized primary sensory neurons ofSNS–IKKβ−/−mice during stimulation with capsaicin or Formalin, specific activators of transient receptor potentials TRPV1 and TRPA1 calcium channels, respectively.In vitrostimulation of saphenous nerve preparations ofSNS–IKKβ−/−mice showed increased neuronal excitability of A- and C-fibers but unchanged A- and C-fiber conduction velocities, normal voltage-gated sodium channel currents, and normal accumulation of ankyrin G and the sodium channels Nav1.6 at NR. The results suggest that IKKβ functions as a negative modulator of sensory neuron excitability, mediated at least in part by modulation of TRP channel sensitivity.
Retrograde Viral Vector-Mediated Inhibition of Pontospinal Noradrenergic Neurons Causes Hyperalgesia in Rats
Authors: Howorth Patrick W. , Thornton Simon R. , O'Brien Victoria , Smith Wynne D. , Nikiforova Natalia , Teschemacher Anja G. , Pickering Anthony E.
Published: October 2009

Pontospinal noradrenergic neurons form a component of an endogenous analgesic system and represent a potential therapeutic target. We tested the principle that genetic manipulation of their excitability can alter nociception using an adenoviral vector (AVV-PRS-hKir2.1) containing a catecholaminergic-selective promoter (PRS) to retrogradely transduce and inhibit the noradrenergic neurons projecting to the lumbar dorsal horn through the expression of a potassium channel (hKir2.1). Expression of hKir2.1in catecholaminergic PC12 cells hyperpolarized the membrane potential and produced a barium-sensitive inward rectification. LC neurons transduced by AVV-PRS-hKir2.1in slice cultures also showed barium-sensitive inward rectification and reduced spontaneous firing rate (median 0.2 Hz;n= 19 vs control 1.0 Hz;n= 18,p< 0.05). Pontospinal noradrenergic neurons were retrogradely transducedin vivoby injection of AVV into the lumbar dorsal horn (L4–5). Rats transduced with AVV-PRS-hKir2.1showed thermal but not mechanical hyperalgesia. Similar selective augmentation of thermal hyperalgesia was seen in the CFA-inflammatory pain model after AVV-PRS-hKir2.1. In the formalin test, rats transduced with hKir2.1showed enhanced nocifensive behaviors (both Phase I and II,p< 0.05,n= 11/group) and increased c-Fos-positive cells in the lumbar dorsal horn. Transduction with AVV-PRS-hKir2.1before spared nerve injury produced no change in tactile or cold allodynia. Thus, the selective genetic inhibition of ∼150 pontospinal noradrenergic neurons produces a modality-specific thermal hyperalgesia, increased nocifensive behaviors, and spinal c-Fos expression in the formalin test, but not in the spared nerve injury model of neuropathic pain, indicating that these neurons exert a selective tonic restraining influence onin vivonociception.