Application of Spectroscopic Methods for Structural Analysis of Chitin and Chitosan

Directory of Open Access Journals (Sweden)

Jolanta Kumirska

2010-04-01

Full Text Available Chitin, the second most important natural polymer in the world, and its N-deacetylated derivative chitosan, have been identified as versatile biopolymers for a broad range of applications in medicine, agriculture and the food industry. Two of the main reasons for this are firstly the unique chemical, physicochemical and biological properties of chitin and chitosan, and secondly the unlimited supply of raw materials for their production. These polymers exhibit widely differing physicochemical properties depending on the chitin source and the conditions of chitosan production. The presence of reactive functional groups as well as the polysaccharide nature of these biopolymers enables them to undergo diverse chemical modifications. A complete chemical and physicochemical characterization of chitin, chitosan and their derivatives is not possible without using spectroscopic techniques. This review focuses on the application of spectroscopic methods for the structural analysis of these compounds.

Quantitative comparison of analysis methods for spectroscopic optical coherence tomography: reply to comment

NARCIS (Netherlands)

Bosschaart, Nienke; van Leeuwen, Ton; Aalders, Maurice C.G.; Faber, Dirk

2014-01-01

We reply to the comment by Kraszewski et al on “Quantitative comparison of analysis methods for spectroscopic optical coherence tomography.” We present additional simulations evaluating the proposed window function. We conclude that our simulations show good qualitative agreement with the results of

Spectroscopic and chromatographic analysis of oil from an oil shale flash pyrolysis unit

Energy Technology Data Exchange (ETDEWEB)

Khraisha, V.H.; Irqsousi, N.A. [University of Jordan, Amman (Jordan). Dept. of Chemical Engineering; Shabib, I.M. [Applied Science Univ., Amman (Jordan). Dept. of Chemistry

2003-01-01

In this investigation, spectroscopic (FT-IR, UV-Vis, {sup 1}H NMR) and chromatographic (GC) techniques were used to analyze two Jordanian shale oils, Sultani and El-Lajjun. The oils were extracted at different pyrolysis temperatures (400-500{sup o}C) using a fluidized bed reactor. The spectroscopic and chromatographic analyses show that the variation of pyrolysis temperature has no significant effect on the composition of the produced oil. The {sup 1}H NMR results indicate that the protons of methyl and methelyene represent the bulk of the hydrogen ({approx}90%) in most shale oil samples. GC analysis reveals that the oil samples contain n-alkanes with a predominant proportion of n-C{sub 25}. (Author)

Raman spectroscopic analysis of a `noli me tangere' painting

Science.gov (United States)

Hibberts, Stephen; Edwards, Howell G. M.; Abdel-Ghani, Mona; Vandenabeele, Peter

2016-12-01

The discovery of an oil painting in seriously damaged condition with an important historical and a heterodox detail with possible origins in the late fifteenth century has afforded the opportunity for Raman microscopic analysis prior to its restoration being undertaken. The painting depicts a risen Christ following His crucifixion in a `noli me tangere' pose with three women in an Italian terrace garden with a stone balustrade overlooking a rural landscape and an undoubted view of late-medieval Florence. The picture has suffered much abuse and is in very poor condition, which is possibly attributable to its controversial portrayal of a polydactylic Christ with six toes on His right foot. By the late sixteenth century, after the Council of Trent, this portrayal would almost certainly have been frowned upon by the Church authorities or more controversially as a depiction of the holy. Raman spectroscopic analysis of the pigments places the painting as being consistent chronologically with the Renaissance period following the identification of cinnabar, haematite, red lead, lead white, goethite, verdigris, caput mortuum and azurite with no evidence of more modern synthetic pigments or of modern restoration having been carried out. An interesting pigment mixture found here is that of the organic dye carmine and cinnabar to produce a particular bright red pigment coloration. Stratigraphic examination of the paint fragments has demonstrated the presence of an orange resin layer immediately on top of the canvas substrate, effectively rendering the pigment as a sandwich between this substratal resin and the overlying varnish. The Raman spectroscopic evidence clearly indicates that an attribution of the artwork to the Renaissance is consistent with the scientific analysis of the pigment composition. This article is part of the themed issue "Raman spectroscopy in art and archaeology".

Raman spectroscopic analysis of a 'noli me tangere' painting.

Science.gov (United States)

Hibberts, Stephen; Edwards, Howell G M; Abdel-Ghani, Mona; Vandenabeele, Peter

2016-12-13

The discovery of an oil painting in seriously damaged condition with an important historical and a heterodox detail with possible origins in the late fifteenth century has afforded the opportunity for Raman microscopic analysis prior to its restoration being undertaken. The painting depicts a risen Christ following His crucifixion in a 'noli me tangere' pose with three women in an Italian terrace garden with a stone balustrade overlooking a rural landscape and an undoubted view of late-medieval Florence. The picture has suffered much abuse and is in very poor condition, which is possibly attributable to its controversial portrayal of a polydactylic Christ with six toes on His right foot. By the late sixteenth century, after the Council of Trent, this portrayal would almost certainly have been frowned upon by the Church authorities or more controversially as a depiction of the holy. Raman spectroscopic analysis of the pigments places the painting as being consistent chronologically with the Renaissance period following the identification of cinnabar, haematite, red lead, lead white, goethite, verdigris, caput mortuum and azurite with no evidence of more modern synthetic pigments or of modern restoration having been carried out. An interesting pigment mixture found here is that of the organic dye carmine and cinnabar to produce a particular bright red pigment coloration. Stratigraphic examination of the paint fragments has demonstrated the presence of an orange resin layer immediately on top of the canvas substrate, effectively rendering the pigment as a sandwich between this substratal resin and the overlying varnish. The Raman spectroscopic evidence clearly indicates that an attribution of the artwork to the Renaissance is consistent with the scientific analysis of the pigment composition.This article is part of the themed issue 'Raman spectroscopy in art and archaeology'. © 2016 The Author(s).

Hydrate formation during wet granulation studied by spectroscopic methods and multivariate analysis

DEFF Research Database (Denmark)

Jørgensen, Anna; Rantanen, Jukka; Karjalainen, Milja

2002-01-01

PURPOSE: The aim was to follow hydrate formation of two structurally related drugs, theophylline and caffeine, during wet granulation using fast and nondestructive spectroscopic methods. METHODS: Anhydrous theophylline and caffeine were granulated with purified water. Charge-coupled device (CCD......) Raman spectroscopy was compared with near-infrared spectroscopy (NIR) in following hydrate formation of drugs during wet granulation (off-line). To perform an at-line process analysis, the effect of water addition was monitored by NIR spectroscopy and principal components analysis (PCA). The changes...

Spectroscopic analysis of Cepheid variables with 2D radiation-hydrodynamic simulations

Science.gov (United States)

Vasilyev, Valeriy

2018-06-01

The analysis of chemical enrichment history of dwarf galaxies allows to derive constraints on their formation and evolution. In this context, Cepheids play a very important role, as these periodically variable stars provide a means to obtain accurate distances. Besides, chemical composition of Cepheids can provide a strong constraint on the chemical evolution of the system. Standard spectroscopic analysis of Cepheids is based on using one-dimensional (1D) hydrostatic model atmospheres, with convection parametrised using the mixing-length theory. However, this quasi-static approach has theoretically not been validated. In my talk, I will discuss the validity of the quasi-static approximation in spectroscopy of short-periodic Cepheids. I will show the results obtained using a 2D time-dependent envelope model of a pulsating star computed with the radiation-hydrodynamics code CO5BOLD. I will then describe the impact of new models on the spectroscopic diagnostic of the effective temperature, surface gravity, microturbulent velocity, and metallicity. One of the interesting findings of my work is that 1D model atmospheres provide unbiased estimates of stellar parameters and abundances of Cepheid variables for certain phases of their pulsations. Convective inhomogeneities, however, also introduce biases. I will then discuss how these results can be used in a wider parameter space of pulsating stars and present an outlook for the future studies.

Temperature analysis of laser ignited metalized material using spectroscopic technique

Science.gov (United States)

Bassi, Ishaan; Sharma, Pallavi; Daipuriya, Ritu; Singh, Manpreet

2018-05-01

The temperature measurement of the laser ignited aluminized Nano energetic mixture using spectroscopy has a great scope in in analysing the material characteristic and combustion analysis. The spectroscopic analysis helps to do in depth study of combustion of materials which is difficult to do using standard pyrometric methods. Laser ignition was used because it consumes less energy as compared to electric ignition but ignited material dissipate the same energy as dissipated by electric ignition and also with the same impact. Here, the presented research is primarily focused on the temperature analysis of energetic material which comprises of explosive material mixed with nano-material and is ignited with the help of laser. Spectroscopy technique is used here to estimate the temperature during the ignition process. The Nano energetic mixture used in the research does not comprise of any material that is sensitive to high impact.

Near infrared spectroscopic (NIRS) analysis of grapes and red-wines

International Nuclear Information System (INIS)

Guggenbichler, W.

2003-04-01

In this work vine varieties of the genus Vitis as well as grape-must and fully developed wines were examined by Near Infrared Spectroscopy (NIRS). The spectra were obtained by methods of transflection and transmission measurements. It was shown, that spectra of different varieties of grapes and red-wines can be combined in clusters by means of NIR spectroscopy and subsequent principle components analysis (PCA). In addition to this, it was possible to identify blends of two different varieties of wines as such and to determine the ratio of mixture. In several varieties of grape-must these NIR spectroscopic measurements further allowed a quantitative determination of important parameters concerning the quality of grapes, such as: sugar, total acidity, tartaric acid, malic acid, and pH-value. The content of polyphenols in grapes was also analyzed by this method. The total parameter for polyphenols in grapes is a helpful indicator for the optimal harvest time and the quality of grapes. All quantitative calculations were made by the method of partial least square regression (PLS). As these spectroscopic measurements require minimal sample preparations and due to the fact that measurements can be accomplished and results obtained within a few seconds, this method turned out to be a promising option in order to classify wines and to quantify relevant ingredients in grapes. (author)

Spectroscopic vector analysis for fast pattern quality monitoring

Science.gov (United States)

Sohn, Younghoon; Ryu, Sungyoon; Lee, Chihoon; Yang, Yusin

2018-03-01

In semiconductor industry, fast and effective measurement of pattern variation has been key challenge for assuring massproduct quality. Pattern measurement techniques such as conventional CD-SEMs or Optical CDs have been extensively used, but these techniques are increasingly limited in terms of measurement throughput and time spent in modeling. In this paper we propose time effective pattern monitoring method through the direct spectrum-based approach. In this technique, a wavelength band sensitive to a specific pattern change is selected from spectroscopic ellipsometry signal scattered by pattern to be measured, and the amplitude and phase variation in the wavelength band are analyzed as a measurement index of the pattern change. This pattern change measurement technique is applied to several process steps and verified its applicability. Due to its fast and simple analysis, the methods can be adapted to the massive process variation monitoring maximizing measurement throughput.

Spectroscopic characterization of low dose rate brachytherapy sources

Science.gov (United States)

Beach, Stephen M.

The low dose rate (LDR) brachytherapy seeds employed in permanent radioactive-source implant treatments usually use one of two radionuclides, 125I or 103Pd. The theoretically expected source spectroscopic output from these sources can be obtained via Monte Carlo calculation based upon seed dimensions and materials as well as the bare-source photon emissions for that specific radionuclide. However the discrepancies resulting from inconsistent manufacturing of sources in comparison to each other within model groups and simplified Monte Carlo calculational geometries ultimately result in undesirably large uncertainties in the Monte Carlo calculated values. This dissertation describes experimentally attained spectroscopic outputs of the clinically used brachytherapy sources in air and in liquid water. Such knowledge can then be applied to characterize these sources by a more fundamental and metro logically-pure classification, that of energy-based dosimetry. The spectroscopic results contained within this dissertation can be utilized in the verification and benchmarking of Monte Carlo calculational models of these brachytherapy sources. This body of work was undertaken to establish a usable spectroscopy system and analysis methods for the meaningful study of LDR brachytherapy seeds. The development of a correction algorithm and the analysis of the resultant spectroscopic measurements are presented. The characterization of the spectrometer and the subsequent deconvolution of the measured spectrum to obtain the true spectrum free of any perturbations caused by the spectrometer itself is an important contribution of this work. The approach of spectroscopic deconvolution that was applied in this work is derived in detail and it is applied to the physical measurements. In addition, the spectroscopically based analogs to the LDR dosimetry parameters that are currently employed are detailed, as well as the development of the theory and measurement methods to arrive at these

Principal component and spatial correlation analysis of spectroscopic-imaging data in scanning probe microscopy

International Nuclear Information System (INIS)

Jesse, Stephen; Kalinin, Sergei V

2009-01-01

An approach for the analysis of multi-dimensional, spectroscopic-imaging data based on principal component analysis (PCA) is explored. PCA selects and ranks relevant response components based on variance within the data. It is shown that for examples with small relative variations between spectra, the first few PCA components closely coincide with results obtained using model fitting, and this is achieved at rates approximately four orders of magnitude faster. For cases with strong response variations, PCA allows an effective approach to rapidly process, de-noise, and compress data. The prospects for PCA combined with correlation function analysis of component maps as a universal tool for data analysis and representation in microscopy are discussed.

Laser apparatus and method for microscopic and spectroscopic analysis and processing of biological cells

Science.gov (United States)

Gourley, P.L.; Gourley, M.F.

1997-03-04

An apparatus and method are disclosed for microscopic and spectroscopic analysis and processing of biological cells. The apparatus comprises a laser having an analysis region within the laser cavity for containing one or more biological cells to be analyzed. The presence of a cell within the analysis region in superposition with an activated portion of a gain medium of the laser acts to encode information about the cell upon the laser beam, the cell information being recoverable by an analysis means that preferably includes an array photodetector such as a CCD camera and a spectrometer. The apparatus and method may be used to analyze biomedical cells including blood cells and the like, and may include processing means for manipulating, sorting, or eradicating cells after analysis. 20 figs.

Development of atomic spectroscopy technology -Development of ultrasensitive spectroscopic analysis technology

Energy Technology Data Exchange (ETDEWEB)

Cha, Hyung Kee; Suk, Song Kyoo; Kim, Duk Hyun; Hong, Suk Kyung; Lee, Yong Joo; Lee, Jong Hoon; Yang, Kee Hoh [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1995-07-01

For the resonance ionization spectroscopy experiment, erbium and samarium were chosen as test elements and their optimum photoionization schemes for trace analysis have been investigated by using multiphoton spectroscopic techniques. With the optimum scheme, the detection limit of various atoms were measured. For the test of laser induced fluorescence system, calibration curves obtained from lead and cadmium standard solutions were made and Pb concentrations of various unknown solutions were determined. By using the developed differential absorption lidar system, backscattering signals from aerosol and ozone have been measured. Error source, error calibration and data interpretation techniques have been also studied. 60 figs, 8 pix, 28 tabs, 30 refs. (Author).

Development of atomic spectroscopy technology -Development of ultrasensitive spectroscopic analysis technology

International Nuclear Information System (INIS)

Cha, Hyung Kee; Song Kyoo Suk; Kim, Duk Hyun; Hong, Suk Kyung; Lee, Yong Joo; Lee, Jong Hoon; Yang, Kee Hoh

1995-07-01

For the resonance ionization spectroscopy experiment, erbium and samarium were chosen as test elements and their optimum photoionization schemes for trace analysis have been investigated by using multiphoton spectroscopic techniques. With the optimum scheme, the detection limit of various atoms were measured. For the test of laser induced fluorescence system, calibration curves obtained from lead and cadmium standard solutions were made and Pb concentrations of various unknown solutions were determined. By using the developed differential absorption lidar system, backscattering signals from aerosol and ozone have been measured. Error source, error calibration and data interpretation techniques have been also studied. 60 figs, 8 pix, 28 tabs, 30 refs. (Author)

Tissue preservation with mass spectroscopic analysis: Implications for cancer diagnostics.

Science.gov (United States)

Hall, O Morgan; Peer, Cody J; Figg, William D

2018-05-17

Surgical intervention is a common treatment modality for localized cancer. Post-operative analysis involves evaluation of surgical margins to assess whether all malignant tissue has been resected because positive surgical margins lead to a greater likelihood of recurrence. Secondary treatments are utilized to minimize the negative effects of positive surgical margins. Recently, in Science Translational Medicine, Zhang et al describe a new mass spectroscopic technique that could potentially decrease the likelihood of positive surgical margins. Their nondestructive in vivo tissue sampling leads to a highly accurate and rapid cancer diagnosis with great precision between healthy and malignant tissue. This new tool has the potential to improve surgical margins and accelerate cancer diagnostics by analyzing biomolecular signatures of various tissues and diseases.

8th Czechoslovak spectroscopic conference. Abstracts

International Nuclear Information System (INIS)

1988-01-01

Volume 3 of the conference proceedings contains abstracts of 17 invited papers, 101 poster presentations and 7 papers of instrument manufacturers, devoted to special spectroscopic techniques including X-ray microanalysis, X-ray spectral analysis, Moessbauer spectrometry, mass spectrometry, instrumental activation analysis and other instrumental radioanalytical methods, electron spectrometry, and techniques of environmental analysis. Sixty abstracts were inputted in INIS. (A.K.)

Spectroscopic Parameters of Lumbar Intervertebral Disc Material

Science.gov (United States)

Terbetas, G.; Kozlovskaja, A.; Varanius, D.; Graziene, V.; Vaitkus, J.; Vaitkuviene, A.

2009-06-01

There are numerous methods of investigating intervertebral disc. Visualization methods are widely used in clinical practice. Histological, imunohistochemical and biochemical methods are more used in scientific research. We propose that a new spectroscopic investigation would be useful in determining intervertebral disc material, especially when no histological specimens are available. Purpose: to determine spectroscopic parameters of intervertebral disc material; to determine emission spectra common for all intervertebral discs; to create a background for further spectroscopic investigation where no histological specimen will be available. Material and Methods: 20 patients, 68 frozen sections of 20 μm thickness from operatively removed intervertebral disc hernia were excited by Nd:YAG microlaser STA-01-TH third harmonic 355 nm light throw 0, 1 mm fiber. Spectrophotometer OceanOptics USB2000 was used for spectra collection. Mathematical analysis of spectra was performed by ORIGIN multiple Gaussian peaks analysis. Results: In each specimen of disc hernia were found distinct maximal spectral peaks of 4 types supporting the histological evaluation of mixture content of the hernia. Fluorescence in the spectral regions 370-700 nm was detected in the disc hernias. The main spectral component was at 494 nm and the contribution of the components with the peak wavelength values at 388 nm, 412 nm and 435±5 nm were varying in the different groups of samples. In comparison to average spectrum of all cases, there are 4 groups of different spectral signatures in the region 400-500 nm in the patient groups, supporting a clinical data on different clinical features of the patients. Discussion and Conclusion: besides the classical open discectomy, new minimally invasive techniques of treating intervertebral disc emerge (PLDD). Intervertebral disc in these techniques is assessed by needle, no histological specimen is taken. Spectroscopic investigation via fiber optics through the

Gas Chromatography-Mass Spectroscopic (GC-MS) Analysis of n ...

African Journals Online (AJOL)

1Department of Pharmacognosy and Phytotherapy, 2Department of Pharmaceutics and Pharmaceutical Technology, University of Port Harcourt, Nigeria ... tuber-regium (synonym Pleurotus tuber regium) using gas chromatography-mass spectroscopic (GC- ... Department of Plant Science and Biotechnology,. University of ...

Spectroscopic analysis applied to temperature measurement in plasmas

International Nuclear Information System (INIS)

Fieffe-Prevost, P.

1978-01-01

The plasma temperature is defined only if the plasma is in a state near thermodynamic equilibrium. This plasma state is analysed in detail and spectroscopic methods for measuring the temperature are discussed. As an application the hydrogen arc of the National Institute of Metrology of the Conservatoire National des Arts et Metiers (Paris) is briefly described [fr

Laser spectroscopic analysis in atmospheric pollution research

CSIR Research Space (South Africa)

Forbes, PBC

2008-01-01

Full Text Available stream_source_info ForbesP_2008.pdf.txt stream_content_type text/plain stream_size 3174 Content-Encoding ISO-8859-1 stream_name ForbesP_2008.pdf.txt Content-Type text/plain; charset=ISO-8859-1 Laser spectroscopic... Department and a CSIR National Laser Centre rental pool programme grant-holder, is involved in research into a novel method of monitoring atmospheric PAHs. The rental pool programme gives South African tertiary education institutions access to an array...

FT-Raman spectroscopic analysis of pigments from an Augustinian friary.

Science.gov (United States)

Edwards, Howell G M; Newton, Emma M; O'Connor, Sonia; Evans, D

2010-08-01

The Raman spectroscopic analysis of several stone samples with applied red pigments obtained from an archaeological excavation of an Augustinian friary discovered during the construction of an extension to Hull Magistrates Court in 1994 has revealed a surprising diversity of composition. Cinnabar, red lead and haematite have all been identified alone or in admixture; the cinnabar is exceptional in that it has only been found heavily adulterated with red ochre and red lead, as the other two pigments are found alone. There are signatures of limewash putty, which has been applied to the stone substrate prior to the painting, which is characteristic of the Roman method of wall painting, and there are no traces of gypsum found in the specimens studied. This evidence indicates an early mediaeval method of stone decoration.

Continuous spectroscopic analysis of vanadous and vanadic ions

International Nuclear Information System (INIS)

Bishop, J.V.; Dutcher, R.A.; Fisher, M.S.; Kottle, S.; Stowe, R.A.

1993-10-01

Spectroscopic methods were investigated for the determination of vanadium ions in aqueous solutions arising in the production of vanadium (11) formate and its use in the LOMI (Low Oxidation-state Metal Ion) process for the chemical decontamination of systems in nuclear power plants. In the LOMI process, a dilute solution of vanadous formate and picolinic acid is used. The vanadous formate n reduces metal oxides in the scale on the equipment, causing the scale to break up and become suspended. The picolinic acid chelates these materials and makes them soluble. During the decontamination the progress is followed by analyses of the metal ions and of the radioactivity. When the values stop increasing, the decontamination is terminated. At present, it cannot be determined if the values are no longer changing due to all the scale being removed or due to the vanadous ion being spent. Infrared and ultraviolet-visible analysis were investigated as the means of analyzing for vanadium species. It was found that the complex formed by V(II) with picolinic acid could be used for colorimetric analysis for V(II) in the range of 0 - 0.011 moles/liter, which encompasses the concentration range used in the LOMI process. The findings will be used to develop an on-line instrument for continuously monitoring V(II) during decontamination

Understanding arsenic metabolism through spectroscopic determination of arsenic in human urine

OpenAIRE

Brima, Eid I.; Jenkins, Richard O.; Haris, Parvez I.

2006-01-01

In this review we discuss a range of spectroscopic techniques that are currently used for analysis of arsenic in human urine for understanding arsenic metabolism and toxicity, especially in relation to genetics/ethnicity, ingestion studies and exposure to arsenic through drinking water and diet. Spectroscopic techniques used for analysis of arsenic in human urine include inductively coupled plasma mass spectrometry (ICP-MS), hydride generation atomic absorption spectrometry (HG-AAS), hydride ...

Spectroscopic analysis of 8-hydroxyquinoline derivatives and investigation of its reactive properties by DFT and molecular dynamics simulations

Science.gov (United States)

Sureshkumar, B.; Mary, Y. Sheena; Resmi, K. S.; Panicker, C. Yohannan; Armaković, Stevan; Armaković, Sanja J.; Van Alsenoy, C.; Narayana, B.; Suma, S.

2018-03-01

Two 8-hydroxyquinoline derivatives, 5,7-dichloro-8-hydroxyquinoline (57DC8HQ) and 5-chloro-7-iodo-8-hydroxy quinoline (5CL7I8HQ) have been investigated in details by means of spectroscopic characterization and computational molecular modelling techniques. FT-IR and FT-Raman experimental spectroscopic approaches have been utilized in order to obtain detailed spectroscopic signatures of title compounds, while DFT calculations have been used in order to visualize and assign vibrations. The computed values of dipole moment, polarizability and hyperpolarizability indicate that the title molecules exhibit NLO properties. The evaluated HOMO and LUMO energies demonstrate the chemical stability of the molecules. NBO analysis is made to study the stability of the molecules arising from hyperconjugative interactions and charge delocalization. DFT calculations have been also used jointly with MD simulations in order to investigate in details global and local reactivity properties of title compounds. Also, molecular docking has been also used in order to investigate affinity of title compounds against decarboxylase inhibitor and quinoline derivatives can be a lead compounds for developing new antiparkinsonian drug.

Spectroscopic and asteroseismic analysis of the remarkable main-sequence A star KIC 11145123

DEFF Research Database (Denmark)

Takada-Hidai, Masahide; Kurtz, Donald W.; Shibahashi, Hiromoto

2017-01-01

A spectroscopic analysis was carried out to clarify the properties of KIC 11145123 - the first main-sequence star with a directly measured core-to-surface rotation profile - based on spectra observed with the High Dispersion Spectrograph (HDS) of the Subaru telescope. The atmospheric parameters (T......-eff = 7600 K, log g = 4.2, xi = 3.1 kms(-1) and [Fe/H] = -0.71 dex), the radial and rotation velocities, and elemental abundances were obtained by analysing line strengths and fitting line profiles, which were calculated with a 1D LTE model atmosphere. The main properties of KIC 11145123 are: (1) a low [Fe...

The design and application of a new Bassett-type diamond anvil cell for spectroscopic analysis of supercritical aqueous solutions

International Nuclear Information System (INIS)

Anderson, A.J.; Meredith, P.R.; Bassett, W.A.; Mayanovic, R.A.; Benmore, C.

2010-01-01

The Bassett-type hydrothermal diamond anvil cell has been modified to facilitate direct x-ray and Raman spectroscopic analysis of aqueous solutions and/or coexisting solid samples at temperatures and pressures above the critical point of water. The new cell provides more sample-detector geometry options for x-ray micro beam analysis and the reduced size of the cell affords a smaller working distance (≥ 14 mm) required for better Raman spectroscopic analysis and microscopic inspection. A shallow recess (300 × 300 × 26.5 μm) milled into one of the diamond anvils is used instead of a metal gasket to contain the aqueous solution. These modifications significantly improve our ability to directly monitor the composition and structure of supercritical fluids and have eliminated the problem of contamination due to the reaction of a metal gasket with supercritical water. The use of the modified hydrothermal diamond anvil cell to characterize the MoO 3 -H 2 O system up to 500 o C will be discussed. (author)

Development of ultrasensitive spectroscopic analysis technology -Development of atomic spectroscopy technology-

International Nuclear Information System (INIS)

Cha, Hyung Ki; Song, Ky Seok; Rhee, Young Joo; Baik, Dae Hyun; Shin, Jang Soo; Kim, Duck Hyun; Yang, Ki Ho; Yi, Jong Hoon

1994-07-01

In this project, three principal techniques are developed. The laser photoionization spectrometry (LAPIS) is used for the ultrasensitive detection for heavy metals such as Pb and Cd. The Laser atomic fluorescence spectrometry is applied to the quantitative analysis of the lanthanide and actinide elements. And the DIAL remote sensing system is used for monitoring the ozone concentration and the atmospheric pollution. A time-of-flight mass spectrometer and a high efficient atomic beam generator were designed and manufactured. Various spectroscopic parameters and optimum analytical condition were investigated. By using the laser fluorescence technique, U, Eu and Sm in solution were quantitatively analyzed. The basic researches for the direct analytical method of solid samples were also carried out. The DIAL system for ozone remote sensing was developed and ozone concentration above Taejon were obtained. (Author)

Shell model and spectroscopic factors

International Nuclear Information System (INIS)

Poves, P.

2007-01-01

In these lectures, I introduce the notion of spectroscopic factor in the shell model context. A brief review is given of the present status of the large scale applications of the Interacting Shell Model. The spectroscopic factors and the spectroscopic strength are discussed for nuclei in the vicinity of magic closures and for deformed nuclei. (author)

Spectroscopic analysis of lithium hydroxide and carbonate in solid state lithium oxide

Energy Technology Data Exchange (ETDEWEB)

Oohira, Shigeru; Fujii, Yasuhiko; Okamoto, Makoto; Kakihana, Masato; Nagumo, Tadashi

1985-08-01

Infrared spectra of LiOH and Li2CO3 suspended on KBr discs were measured over the concentration range 20 g/100 mg KBr to 600 g/100 mg KBr. The absorbance of a selected infrared band of each sample was carefully determined. The empirical equation, which expresses a correlation between the absorbance and the concentration, was given for each lithium compound. The feasibility of independent and direct determination of the LiOH and Li2CO3 content in Li2O was shown, and the spectroscopic technique was applied to a typical Li2O sample. It was shown that the detection limit of the analysis was improved by low-temperature measurements of the infrared spectra. (orig.).

Development and validation of a spectroscopic method for the ...

African Journals Online (AJOL)

Development and validation of a spectroscopic method for the simultaneous analysis of ... advanced analytical methods such as high pressure liquid ..... equipment. DECLARATIONS ... high-performance liquid chromatography. J Chromatogr.

[Spectroscopic characteristics of novel Psidium meroterpenoids isolated from guava leaves].

Science.gov (United States)

Ouyang, Wen; Zhu, Xiao-ai; Liu, Xiao-juan; Yie, Shu-min; Zhao, Litchao; Su, Lei; Cao, Yong

2015-07-01

Recently, novel Psidium meroterpenoids were reported in the guava leaves. According to careful analysis of the spectral data of literatures, the spectroscopic characteristics and biosynthetic pathway of Psidium meroterpenoids were summarized in this paper. The results showed that Psidium meroterpenoids had distinct spectroscopic features and reasonable biosynthetic routines, however the number order of carbon atoms was not consistent in the reported literatures. It was concluded that Psidium meroterpenoids were the characteristic chemical constituents of Psidium guajava Linn.

THE BARYON OSCILLATION SPECTROSCOPIC SURVEY OF SDSS-III

International Nuclear Information System (INIS)

Dawson, Kyle S.; Ahn, Christopher P.; Bolton, Adam S.; Schlegel, David J.; Bailey, Stephen; Anderson, Scott F.; Bhardwaj, Vaishali; Aubourg, Éric; Bautista, Julian E.; Barkhouser, Robert H.; Beifiori, Alessandra; Berlind, Andreas A.; Bizyaev, Dmitry; Brewington, Howard; Blake, Cullen H.; Blanton, Michael R.; Blomqvist, Michael; Borde, Arnaud; Bovy, Jo; Brandt, W. N.

2013-01-01

The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large-scale structure. BOSS uses 1.5 million luminous galaxies as faint as i = 19.9 over 10,000 deg 2 to measure BAO to redshifts z A to an accuracy of 1.0% at redshifts z = 0.3 and z = 0.57 and measurements of H(z) to 1.8% and 1.7% at the same redshifts. Forecasts for Lyα forest constraints predict a measurement of an overall dilation factor that scales the highly degenerate D A (z) and H –1 (z) parameters to an accuracy of 1.9% at z ∼ 2.5 when the survey is complete. Here, we provide an overview of the selection of spectroscopic targets, planning of observations, and analysis of data and data quality of BOSS.

Velocity Curve Analysis of the Spectroscopic Binary Stars PV Pup ...

Indian Academy of Sciences (India)

are in good agreement with those obtained using the method of Lehmann-. Filhés. Key words. ... use their method to obtain the orbital elements of the four double-lined spectroscopic binary systems PV Pup, HD ... Observation shows that the photometric phase, φ, which is measured from the pho- tometric reference point ...

Pyrene conjugation and spectroscopic analysis of hydroxypropyl methylcellulose compounds successfully demonstrated a local dielectric difference associated with in vivo anti-prion activity.

Directory of Open Access Journals (Sweden)

Kenta Teruya

Full Text Available Our previous study on prion-infected rodents revealed that hydroxypropyl methylcellulose compounds (HPMCs with different molecular weights but similar composition and degree of substitution have different levels of long-lasting anti-prion activity. In this study, we searched these HPMCs for a parameter specifically associated with in vivo anti-prion activity by analyzing in vitro chemical properties and in vivo tissue distributions. Infrared spectroscopic and thermal analyses revealed no differences among HPMCs, whereas pyrene conjugation and spectroscopic analysis revealed that the fluorescence intensity ratio of peak III/peak I correlated with anti-prion activity. This correlation was more clearly demonstrated in the anti-prion activity of the 1-year pre-infection treatment than that of the immediate post-infection treatment. In addition, the intensity ratio of peak III/peak I negatively correlated with the macrophage uptake level of HPMCs in our previous study. However, the in vivo distribution pattern was apparently not associated with anti-prion activity and was different in the representative tissues. These findings suggest that pyrene conjugation and spectroscopic analysis are powerful methods to successfully demonstrate local dielectric differences in HPMCs and provide a feasible parameter denoting the long-lasting anti-prion activity of HPMCs in vivo.

AN IMPROVED SPECTROSCOPIC ANALYSIS OF DA WHITE DWARFS FROM THE SLOAN DIGITAL SKY SURVEY DATA RELEASE 4

International Nuclear Information System (INIS)

Tremblay, P.-E.; Bergeron, P.; Gianninas, A.

2011-01-01

We present an improved spectroscopic and photometric analysis of hydrogen-line DA white dwarfs from the Sloan Digital Sky Survey Data Release 4 (SDSS DR4) based on model atmospheres that include improved Stark broadening profiles with non-ideal gas effects. We also perform a careful visual inspection of all spectroscopic fits with high signal-to-noise ratios (S/Ns > 12) and present improved atmospheric parameters (T eff and log g) for each white dwarf. Through a comparison of spectroscopic and photometric temperatures, we report the discovery of 35 DA+DB/DC double degenerate candidates and two helium-rich DA stars. We also determine that a cutoff at S/N = 15 optimizes the size and quality of the sample for computing the mean mass of DA white dwarfs, for which we report a value of 0.613 M sun . We compare our results to previous analyses of the SDSS DR4 and find a good agreement if we account for the shift produced by the improved Stark profiles. Finally, the properties of DA white dwarfs in the SDSS are weighed against those of the Villanova White Dwarf Catalog sample of Gianninas et al. We find systematically lower masses (by about 3% on average), a difference that we trace back to the data reduction procedure of the SDSS. We conclude that a better understanding of these differences will be important to determine the absolute temperature scale and mean mass of DA white dwarfs.

Terahertz spectroscopic analysis of crystal orientation in polymers

Science.gov (United States)

Azeyanagi, Chisato; Kaneko, Takuya; Ohki, Yoshimichi

2018-05-01

Terahertz time-domain spectroscopy (THz-TDS) is attracting keen attention as a new spectroscopic tool for characterizing various materials. In this research, the possibility of analyzing the crystal orientation in a crystalline polymer by THz-TDS is investigated by measuring angle-resolved THz absorption spectra for sheets of poly(ethylene terephthalate), poly(ethylene naphthalate), and poly(phenylene sulfide). The resultant angle dependence of the absorption intensity of each polymer is similar to that of the crystal orientation examined using pole figures of X-ray diffraction. More specifically, THz-TDS can indicate the alignment of molecules in polymers.

Spectroscopic classification of transients

DEFF Research Database (Denmark)

Stritzinger, M. D.; Fraser, M.; Hummelmose, N. N.

2017-01-01

We report the spectroscopic classification of several transients based on observations taken with the Nordic Optical Telescope (NOT) equipped with ALFOSC, over the nights 23-25 August 2017.......We report the spectroscopic classification of several transients based on observations taken with the Nordic Optical Telescope (NOT) equipped with ALFOSC, over the nights 23-25 August 2017....

Recent Developments in Solid-Phase Extraction for Near and Attenuated Total Reflection Infrared Spectroscopic Analysis

Directory of Open Access Journals (Sweden)

Christian W. Huck

2016-05-01

Full Text Available A review with more than 100 references on the principles and recent developments in the solid-phase extraction (SPE prior and for in situ near and attenuated total reflection (ATR infrared spectroscopic analysis is presented. New materials, chromatographic modalities, experimental setups and configurations are described. Their advantages for fast sample preparation for distinct classes of compounds containing different functional groups in order to enhance selectivity and sensitivity are discussed and compared. This is the first review highlighting both the fundamentals of SPE, near and ATR spectroscopy with a view to real sample applicability and routine analysis. Most of real sample analyses examples are found in environmental research, followed by food- and bioanalysis. In this contribution a comprehensive overview of the most potent SPE-NIR and SPE-ATR approaches is summarized and provided.

A spectroscopic census in young stellar regions: the σ Orionis cluster

Energy Technology Data Exchange (ETDEWEB)

Hernández, Jesús; Perez, Alice; Hernan, Ramírez [Centro de Investigaciones de Astronomía, Apdo. Postal 264, Mérida 5101-A (Venezuela, Bolivarian Republic of); Calvet, Nuria; Hartmann, Lee [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States); Briceño, Cesar [Cerro Tololo Interamerican Observatory, Casilla 603, La Serena (Chile); Olguin, Lorenzo [Depto. de Investigación en Física, Universidad de Sonora, Sonora (Mexico); Contreras, Maria E. [Instituto de Astronomía, Universidad Nacional Autónoma de México, Ensenada, BC (Mexico); Allen, Lori [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Espaillat, Catherine, E-mail: hernandj@cida.ve [Department of Astronomy, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States)

2014-10-10

We present a spectroscopic survey of the stellar population of the σ Orionis cluster. We have obtained spectral types for 340 stars. Spectroscopic data for spectral typing come from several spectrographs with similar spectroscopic coverage and resolution. More than half of the stars in our sample are members confirmed by the presence of lithium in absorption, strong Hα in emission or weak gravity-sensitive features. In addition, we have obtained high-resolution (R ∼ 34,000) spectra in the Hα region for 169 stars in the region. Radial velocities were calculated from this data set. The radial velocity distribution for members of the cluster is in agreement with previous work. Analysis of the profile of the Hα line and infrared observations reveals two binary systems or fast rotators that mimic the Hα width expected in stars with accretion disks. On the other hand, there are stars with optically thick disks and narrow Hα profiles not expected in stars with accretion disks. This contribution constitutes the largest homogeneous spectroscopic data set of the σ Orionis cluster to date.

Optimal Background Attenuation for Fielded Spectroscopic Detection Systems

International Nuclear Information System (INIS)

Robinson, Sean M.; Ashbaker, Eric D.; Schweppe, John E.; Siciliano, Edward R.

2007-01-01

Radiation detectors are often placed in positions difficult to shield from the effects of terrestrial background gamma radiation. This is particularly true in the case of Radiation Portal Monitor (RPM) systems, as their wide viewing angle and outdoor installations make them susceptible to radiation from the surrounding area. Reducing this source of background can improve gross-count detection capabilities in the current generation of non-spectroscopic RPM's as well as source identification capabilities in the next generation of spectroscopic RPM's. To provide guidance for designing such systems, the problem of shielding a general spectroscopic-capable RPM system from terrestrial gamma radiation is considered. This analysis is carried out by template matching algorithms, to determine and isolate a set of non-threat isotopes typically present in the commerce stream. Various model detector and shielding scenarios are calculated using the Monte-Carlo N Particle (MCNP) computer code. Amounts of nominal-density shielding needed to increase the probability of detection for an ensemble of illicit sources are given. Common shielding solutions such as steel plating are evaluated based on the probability of detection for 3 particular illicit sources of interest, and the benefits are weighed against the incremental cost of shielding. Previous work has provided optimal shielding scenarios for RPMs based on gross-counting measurements, and those same solutions (shielding the internal detector cavity, direct shielding of the ground between the detectors, and the addition of collimators) are examined with respect to their utility to improving spectroscopic detection

Spectroscopically Enhanced Method and System for Multi-Factor Biometric Authentication

Science.gov (United States)

Pishva, Davar

This paper proposes a spectroscopic method and system for preventing spoofing of biometric authentication. One of its focus is to enhance biometrics authentication with a spectroscopic method in a multifactor manner such that a person's unique ‘spectral signatures’ or ‘spectral factors’ are recorded and compared in addition to a non-spectroscopic biometric signature to reduce the likelihood of imposter getting authenticated. By using the ‘spectral factors’ extracted from reflectance spectra of real fingers and employing cluster analysis, it shows how the authentic fingerprint image presented by a real finger can be distinguished from an authentic fingerprint image embossed on an artificial finger, or molded on a fingertip cover worn by an imposter. This paper also shows how to augment two widely used biometrics systems (fingerprint and iris recognition devices) with spectral biometrics capabilities in a practical manner and without creating much overhead or inconveniencing their users.

Zinc acetylacetonate hydrate adducted with nitrogen donor ligands: Synthesis, spectroscopic characterization, and thermal analysis

Science.gov (United States)

Brahma, Sanjaya; Shivashankar, S. A.

2015-12-01

We report synthesis, spectroscopic characterization, and thermal analysis of zinc acetylacetonate complex adducted by nitrogen donor ligands, such as pyridine, bipyridine, and phenanthroline. The pyridine adducted complex crystallizes to monoclinic crystal structure, whereas other two adducted complexes have orthorhombic structure. Addition of nitrogen donor ligands enhances the thermal property of these complexes as that with parent metal-organic complex. Zinc acetylacetonate adducted with pyridine shows much higher volatility (106 °C), decomposition temperature (202 °C) as that with zinc acetylacetonate (136 °C, 220 °C), and other adducted complexes. All the adducted complexes are thermally stable, highly volatile and are considered to be suitable precursors for metal organic chemical vapor deposition. The formation of these complexes is confirmed by powder X-ray diffraction, Fourier transform infrared spectroscopy, mass spectroscopy, and elemental analysis. The complexes are widely used as starting precursor materials for the synthesis of ZnO nanostructures by microwave irradiation assisted coating process.

Optimal methodologies for terahertz time-domain spectroscopic analysis of traditional pigments in powder form

Science.gov (United States)

Ha, Taewoo; Lee, Howon; Sim, Kyung Ik; Kim, Jonghyeon; Jo, Young Chan; Kim, Jae Hoon; Baek, Na Yeon; Kang, Dai-ill; Lee, Han Hyoung

2017-05-01

We have established optimal methods for terahertz time-domain spectroscopic analysis of highly absorbing pigments in powder form based on our investigation of representative traditional Chinese pigments, such as azurite [blue-based color pigment], Chinese vermilion [red-based color pigment], and arsenic yellow [yellow-based color pigment]. To accurately extract the optical constants in the terahertz region of 0.1 - 3 THz, we carried out transmission measurements in such a way that intense absorption peaks did not completely suppress the transmission level. This required preparation of pellet samples with optimized thicknesses and material densities. In some cases, mixing the pigments with polyethylene powder was required to minimize absorption due to certain peak features. The resulting distortion-free terahertz spectra of the investigated set of pigment species exhibited well-defined unique spectral fingerprints. Our study will be useful to future efforts to establish non-destructive analysis methods of traditional pigments, to construct their spectral databases, and to apply these tools to restoration of cultural heritage materials.

Spectroscopic properties of highly Nd-doped lead phosphate glass

Energy Technology Data Exchange (ETDEWEB)

Novais, A.L.F. [Instituto de Física, Universidade Federal de Alagoas, Grupo de Fotônica e Fluidos Complexos, 57072-970 Maceió, AL (Brazil); Dantas, N.O. [Laboratório de Novos Materiais Isolantes e Semicondutores (LNMIS), Instituto de Física, Universidade Federal de Uberlândia, 38400-902 Uberlândia, MG (Brazil); Guedes, I. [Departamento de Física, Universidade Federal do Ceará, Campus do PICI, Caixa Postal 6030, 60455-760 Fortaleza, CE (Brazil); Vermelho, M.V.D., E-mail: vermelho@fis.ufal.br [Instituto de Física, Universidade Federal de Alagoas, Grupo de Fotônica e Fluidos Complexos, 57072-970 Maceió, AL (Brazil)

2015-11-05

The spectroscopic characteristics of highly Nd{sup 3+}-doped lead phosphate glasses (xNd:Pb{sub 3}(PO{sub 4}){sub 2}) have been investigated. The X-ray spectra show that the matrices are glassy up to 25 wt% of Nd{sup 3+} doping. From the Judd–Ofelt analysis we observe that while the Ω{sub (2)} parameter remains constant indicating that the 4f{sup N} and 4f{sup N−1}5 d{sup 1} configurations are not affected by the Nd{sup 3+} doping, the behavior of both Ω{sub (4)} and Ω{sub (6)} changes for 15 wt% of Nd{sup 3+} doping. The reduction of the Ω{sub (6)} parameter is related to the increase of the covalence bonding between the ligands and the Nd{sup 3+} ions. At this particular concentration, the radiative lifetime has a four-fold enhancement. Such behaviors are likely to be related to a modification in the glass structure for high Nd{sup 3+} concentrations. - Graphical abstract: Highly doped lead-phosphate glass matrix, with nominal concentration of up to 25 wt%, maintain the spectroscopic properties without deterioration. The analysis concerning the point of view of Nd{sup 3+} ions showed that high concentrations only affects the rare earth electronic charge density distribution. - Highlights: • Spectroscopic characterization of Nd{sub 2}O{sub 3} highly doped lead phosphate glasses. • Phosphate glass doped with Nd{sup 3+} for applications in photonic devices. • Judd–Ofelt analysis in phosphate glasses doped with Neodymium.

FUSE SPECTROSCOPIC ANALYSIS OF THE SLOWEST SYMBIOTIC NOVA AG PEG DURING QUIESCENCE

Science.gov (United States)

Sion, Edward Michael; Godon, Patrick; Katynski, Marcus; Mikolajewska, Joanna

2018-01-01

We present a far ultraviolet spectroscopic analysis of the slowest known symbiotic nova AG Peg (MIII giant + hot white dwarf; P_orb = 818.4 days) which underwent a nova explosion in 1850 followed by a very slow decline that did not end until ~ 1996, marking the beginning of queiscence. Eight years of quiescence ended in June 2015, when AG Peg exhibited a Z And-type outburst with an optical amplitude of ~ 3 magnitudes. We have carried out accretion disk and WD photosphere synthetic spectral modeling of a FUSE spectrum (Froning et al. 2014) obtained on June 5.618, 2003 during the quiescence intervai ~ 12 years before the 2015 outburst. The spectrum is heavily affected by ISM absorption as well as strong broad emission lines. We de-reddened the FUSE fluxes with E(B-V) = 0.10 which is the maximum galactic reddening in the direction of AG Peg and took the distance of 800 pc (Kenyon et al. 1993) but used a range of white dwarf masses, surface temperatures and disk inclination angles. Our analysis also incororates archival HST FOS spectra obtained in 1996 at the onset of quiescence, 147 years after the 1850 nova explosion. The results of our analysis are presented and implications are discussed.This work is supported in part by NASA ADP grant NNX17AF36G to Villanova University.

Spectroscopic analysis of bladder cancer tissues using Fourier transform infrared spectroscopy

Science.gov (United States)

Al-Muslet, Nafie A.; Ali, Essam E.

2012-03-01

Bladder cancer is one of the most common cancers in Africa. It takes several days to reach a diagnosis using histological examinations of specimens obtained by endoscope, which increases the medical expense. Recently, spectroscopic analysis of bladder cancer tissues has received considerable attention as a diagnosis technique due to its sensitivity to biochemical variations in the samples. This study investigated the use of Fourier transform infrared (FTIR) spectroscopy to analyze a number of bladder cancer tissues. Twenty-two samples were collected from 11 patients diagnosed with bladder cancer from different hospitals without any pretreatment. From each patient two samples were collected, one normal and another cancerous. FTIR spectrometer was used to differentiate between normal and cancerous bladder tissues via changes in spectra of these samples. The investigations detected obvious changes in the bands of proteins (1650, 1550 cm-1), lipids (2925, 2850 cm-1), and nucleic acid (1080, 1236 cm-1). The results show that FTIR spectroscopy is promising as a rapid, accurate, nondestructive, and easy to use alternative method for identification and diagnosis of bladder cancer tissues.

Nuclear data for geophysical spectroscopic logging

International Nuclear Information System (INIS)

Schweitzer, J.S.; Hertzog, R.C.; Soran, P.D.

1987-01-01

Nuclear geochemical analysis requires the quantitative measurement of elemental concentrations of trace elements, as well as major elements in widely varying concentrations. This requirement places extreme demands on the quality of the spectroscopic measurements, data rates, and relating observed γ-ray intensities to the original elemental concentration. The relationship between γ-ray intensities and elemental concentration is critically dependent on the specific reaction cross sections and their uncertainties. The elements of highest priority for subsurface geochemical analysis are considered with respect to the importance of competing reactions and the neutron energy regions that are most significant. (author)

Chemical and spectroscopic characterization of a vegetable oil used as dielectric coolant in distribution transformers

Energy Technology Data Exchange (ETDEWEB)

Gomez, Neffer A.; Abonia, Rodrigo, E-mail: rodrigo.abonia@correounivalle.edu.co [Departamento de Quimica, Escuela de Ingenieria Electrica, Universidad del Valle, Cali (Colombia); Cadavid, Hector [Grupo GRALTA, Escuela de Ingenieria Electrica, Universidad del Valle, Cali (Colombia); Vargas, Ines H. [Area de Ingenieria de Distribucion, Empresas Publicas de Medellin (EPM), Medellin (Colombia)

2011-09-15

In this work, a complete UV-Vis, IR and (1H, 13C and DEPT) NMR spectroscopic analysis was performed for a FR3 vegetable oil sample used as dielectric coolant in an experimental distribution transformer. The same spectroscopic analysis was performed for three used FR3 oil samples (i.e., 4 months in use, 8 months in use and 7 years in use), removed from several operating distribution transformers. Comparison of the data indicated that no significant spectroscopic changes, and hence, no structural changes occurred to the oils by the use. Chemical transformations like catalytic hydrogenation (hardening) and hydrolysis were performed to the FR3 oil sample and the obtained products were analyzed by spectroscopic methods in order to collect further structural information about the FR3 oil. Accelerated aging tests in laboratory were also performed for three FR3 oil samples affording interesting information about the structure of the degradation products. These findings would be valuable to search for a spectroscopy-based technique for monitoring the lifetime and performance of this insulating vegetable oil. (author)

Infrared spectroscopic ellipsometry of micrometer-sized SiO2 line gratings

Science.gov (United States)

Walder, Cordula; Zellmeier, Matthias; Rappich, Jörg; Ketelsen, Helge; Hinrichs, Karsten

2017-09-01

For the design and process control of periodic nano-structured surfaces spectroscopic ellipsometry is already established in the UV-VIS spectral regime. The objective of this work is to show the feasibility of spectroscopic ellipsometry in the infrared, exemplarily, on micrometer-sized SiO2 line gratings grown on silicon wafers. The grating period ranges from 10 to about 34 μm. The IR-ellipsometric spectra of the gratings exhibit complex changes with structure variations. Especially in the spectral range of the oxide stretching modes, the presence of a Rayleigh singularity can lead to pronounced changes of the spectrum with the sample geometry. The IR-ellipsometric spectra of the gratings are well reproducible by calculations with the RCWA method (Rigorous Coupled Wave Analysis). Therefore, infrared spectroscopic ellipsometry allows the quantitative characterization and process control of micrometer-sized structures.

Spectroscopic Analysis of a Theropod Dinosaur (Reptilia, Archosauria from the Ipubi Formation, Araripe Basin, Northeastern Brazil

Directory of Open Access Journals (Sweden)

João Hermínio da Silva

2013-01-01

Full Text Available The Araripe Sedimentary Basin is known by the excellence of its fossils, regarding the preservation, diversity, and quantity. Here, we present a spectroscopic analysis using several experimental techniques (X-ray energy dispersion spectroscopy, Fourier-transform infrared spectroscopy as well as X-ray diffraction and thermogravimetric analysis applied in small fragments of bones from the posterior members of a theropod dinosaur. The results agree regarding the different composition of the stone matrix and the fossilized bone, indicating a partial substitution of the material by elements present in the depositional environment. However, differently from what is believed to occur, there is evidence that pyritization is not the only mechanism of fossilization for a specimen of Ipubi formation, but calcification, additionally, plays an important role in the fossil production of this Formation.

Spectroscopic analysis of DA white dwarfs from the McCook and Sion catalog

International Nuclear Information System (INIS)

Gianninas, A; Bergeron, P; Ruiz, M T

2009-01-01

For some years now, we have been gathering optical spectra of DA white dwarfs in an effort to study and define the empirical ZZ Ceti instability strip. However, we have recently expanded this survey to include all the DA white dwarfs in the McCook and Sion catalog down to a limiting visual magnitude of V = 17.5. We present here a spectroscopic analysis of over 1000 DA white dwarfs from this ongoing survey. We have several specific areas of interest most notably the hot DAO white dwarfs, the ZZ Ceti instability strip, and the DA+dM binary systems. Furthermore, we present a comparison of the ensemble properties of our sample with those of other large surveys of DA white dwarfs, paying particular attention to the distribution of mass as a function of effective temperature.

A subspace approach to high-resolution spectroscopic imaging.

Science.gov (United States)

Lam, Fan; Liang, Zhi-Pei

2014-04-01

To accelerate spectroscopic imaging using sparse sampling of (k,t)-space and subspace (or low-rank) modeling to enable high-resolution metabolic imaging with good signal-to-noise ratio. The proposed method, called SPectroscopic Imaging by exploiting spatiospectral CorrElation, exploits a unique property known as partial separability of spectroscopic signals. This property indicates that high-dimensional spectroscopic signals reside in a very low-dimensional subspace and enables special data acquisition and image reconstruction strategies to be used to obtain high-resolution spatiospectral distributions with good signal-to-noise ratio. More specifically, a hybrid chemical shift imaging/echo-planar spectroscopic imaging pulse sequence is proposed for sparse sampling of (k,t)-space, and a low-rank model-based algorithm is proposed for subspace estimation and image reconstruction from sparse data with the capability to incorporate prior information and field inhomogeneity correction. The performance of the proposed method has been evaluated using both computer simulations and phantom studies, which produced very encouraging results. For two-dimensional spectroscopic imaging experiments on a metabolite phantom, a factor of 10 acceleration was achieved with a minimal loss in signal-to-noise ratio compared to the long chemical shift imaging experiments and with a significant gain in signal-to-noise ratio compared to the accelerated echo-planar spectroscopic imaging experiments. The proposed method, SPectroscopic Imaging by exploiting spatiospectral CorrElation, is able to significantly accelerate spectroscopic imaging experiments, making high-resolution metabolic imaging possible. Copyright © 2014 Wiley Periodicals, Inc.

The LAMOST Complete Spectroscopic Survey of Pointing Area (LaCoSSPAr) in the Southern Galactic Cap. I. The Spectroscopic Redshift Catalog

Science.gov (United States)

Yang, Ming; Wu, Hong; Yang, Fan; Lam, Man I.; Cao, Tian-Wen; Wu, Chao-Jian; Zhao, Pin-Song; Zhang, Tian-Meng; Zhou, Zhi-Min; Wu, Xue-Bing; Zhang, Yan-Xia; Shao, Zheng-Yi; Jing, Yi-Peng; Shen, Shi-Yin; Zhu, Yi-Nan; Du, Wei; Lei, Feng-Jie; He, Min; Jin, Jun-Jie; Shi, Jian-Rong; Zhang, Wei; Wang, Jian-Ling; Wu, Yu-Zhong; Zhang, Hao-Tong; Luo, A.-Li; Yuan, Hai-Long; Bai, Zhong-Rui; Kong, Xu; Gu, Qiu-Sheng; Zhou, Xu; Ma, Jun; Hu, Zou; Nie, Jun-Dan; Wang, Jia-Li; Zhang, Yong; Hou, Yong-Hui; Zhao, Yong-Heng

2018-01-01

We present a spectroscopic redshift catalog from the LAMOST Complete Spectroscopic Survey of Pointing Area (LaCoSSPAr) in the Southern Galactic Cap (SGC), which is designed to observe all sources (Galactic and extragalactic) by using repeating observations with a limiting magnitude of r=18.1 {mag} in two 20 {\\deg }2 fields. The project is mainly focusing on the completeness of LAMOST ExtraGAlactic Surveys (LEGAS) in the SGC, the deficiencies of source selection methods, and the basic performance parameters of the LAMOST telescope. In both fields, more than 95% of galaxies have been observed. A post-processing has been applied to the LAMOST 1D spectrum to remove the majority of remaining sky background residuals. More than 10,000 spectra have been visually inspected to measure the redshift by using combinations of different emission/absorption features with an uncertainty of {σ }z/(1+z)visual inspection. Our analysis also indicates that up to one-fourth of the input targets for a typical extragalactic spectroscopic survey might be unreliable. The multi-wavelength data analysis shows that the majority of mid-infrared-detected absorption (91.3%) and emission line galaxies (93.3%) can be well separated by an empirical criterion of W2-W3=2.4. Meanwhile, a fainter sequence paralleled to the main population of galaxies has been witnessed both in M r /W2-W3 and M */W2-W3 diagrams, which could be the population of luminous dwarf galaxies but contaminated by the edge-on/highly inclined galaxies (∼ 30 % ).

Multi-spectroscopic studies on the interaction of human serum albumin with astilbin: Binding characteristics and structural analysis

Energy Technology Data Exchange (ETDEWEB)

Wang, Jin; Li, Shuang; Peng, Xialian; Yu, Qing [Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources, Department Chemistry and Chemical Engineering, Guangxi Normal University, Ministry of Education of China, Guilin 541004 (China); Bian, Hedong, E-mail: gxnuchem312@yahoo.com.cn [Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources, Department Chemistry and Chemical Engineering, Guangxi Normal University, Ministry of Education of China, Guilin 541004 (China); Huang, Fuping [Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources, Department Chemistry and Chemical Engineering, Guangxi Normal University, Ministry of Education of China, Guilin 541004 (China); Liang, Hong, E-mail: lianghongby@yahoo.com.cn [Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources, Department Chemistry and Chemical Engineering, Guangxi Normal University, Ministry of Education of China, Guilin 541004 (China)

2013-04-15

Five spectroscopic techniques were used to investigate the interaction of astilbin (ASN) with human serum albumin (HSA). UV–vis absorption measurements prove that ASN–HSA complex can be formed. The analysis of fluorescence spectra reveal that in the presence of ASN, quenching mechanism of HSA is considered as static quenching. The quenching rate constant k{sub q}, K{sub SV} and the binding constant K were estimated. According to the van't Hoff equation, the thermodynamic parameters enthalpy change (ΔΗ) and entropy change (ΔS) were calculated to be −12.94 kJ mol{sup −1} and 35.92 J mol{sup −1} K{sup −1}, respectively. These indicate that the hydrophobic interaction is the major forces between ASN and HSA, but the hydrogen bond interaction cannot be excluded. The changes in the secondary structure of HSA which was induced by ASN were determined by circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy. -- Graphical abstract: In this paper, the interaction of HSA with ASN was systematically studied under simulated physiological conditions by using UV–vis absorption, CD, FT-IR, fluorescence and Raman spectroscopic approaches. The quenching constant k{sub q}, K{sub SV} and the binding constant K were estimated. The changes in the secondary structure of HSA were studied by Circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy. The UV–visible absorption spectra of HSA in the absence and presence of different concentration of ASN (1) and fluorescence spectra of HSA in the absence and the presence of ASN (2). Highlights: ► Interaction of ASN and HSA has been studied by five spectroscopic techniques. ► Hydrophobic interaction is the major forces between ASN and HSA. ► Binding of ASN induced the changes in the secondary structure of HSA.

Spectroscopic ellipsometry analysis of a thin film composite membrane consisting of polysulfone on a porous α-alumina support.

Science.gov (United States)

Ogieglo, Wojciech; Wormeester, Herbert; Wessling, Matthias; Benes, Nieck E

2012-02-01

Exposure of a thin polymer film to a fluid can affect properties of the film such as the density and thickness. In particular in membrane technology, these changes can have important implications for membrane performance. Spectroscopic ellipsometry is a convenient technique for in situ studies of thin films, because of its noninvasive character and very high precision. The applicability of spectroscopic ellipsometry is usually limited to samples with well-defined interfacial regions, whereas in typical composite membranes, often substantial and irregular intrusion of the thin film into the pores of a support exists. In this work, we provide a detailed characterization of a polished porous alumina membrane support, using variable-angle spectroscopic ellipsometry in combination with atomic force microscopy and mercury porosimetry. Two Spectroscopic ellipsometry optical models are presented that can adequately describe the surface roughness of the support. These models consider the surface roughness as a distinct layer in which the porosity gradually increases toward the outer ambient interface. The first model considers the porosity profile to be linear; the second model assumes an exponential profile. It is shown that the models can be extended to account for a composite membrane geometry, by deposition of a thin polysulfone film onto the support. The developed method facilitates practicability for in situ spectroscopic ellipsometry studies of nonequilibrium systems, i.e., membranes under actual permeation conditions.

Enhancing forensic science with spectroscopic imaging

Science.gov (United States)

Ricci, Camilla; Kazarian, Sergei G.

2006-09-01

This presentation outlines the research we are developing in the area of Fourier Transform Infrared (FTIR) spectroscopic imaging with the focus on materials of forensic interest. FTIR spectroscopic imaging has recently emerged as a powerful tool for characterisation of heterogeneous materials. FTIR imaging relies on the ability of the military-developed infrared array detector to simultaneously measure spectra from thousands of different locations in a sample. Recently developed application of FTIR imaging using an ATR (Attenuated Total Reflection) mode has demonstrated the ability of this method to achieve spatial resolution beyond the diffraction limit of infrared light in air. Chemical visualisation with enhanced spatial resolution in micro-ATR mode broadens the range of materials studied with FTIR imaging with applications to pharmaceutical formulations or biological samples. Macro-ATR imaging has also been developed for chemical imaging analysis of large surface area samples and was applied to analyse the surface of human skin (e.g. finger), counterfeit tablets, textile materials (clothing), etc. This approach demonstrated the ability of this imaging method to detect trace materials attached to the surface of the skin. This may also prove as a valuable tool in detection of traces of explosives left or trapped on the surfaces of different materials. This FTIR imaging method is substantially superior to many of the other imaging methods due to inherent chemical specificity of infrared spectroscopy and fast acquisition times of this technique. Our preliminary data demonstrated that this methodology will provide the means to non-destructive detection method that could relate evidence to its source. This will be important in a wider crime prevention programme. In summary, intrinsic chemical specificity and enhanced visualising capability of FTIR spectroscopic imaging open a window of opportunities for counter-terrorism and crime-fighting, with applications ranging

Preparation and spectroscopic analysis of zinc oxide nanorod thin films of different thicknesses

Directory of Open Access Journals (Sweden)

Mia Nasrul Haque

2017-10-01

Full Text Available Zinc oxide thin films with different thicknesses were prepared on microscopic glass slides by sol-gel spin coating method, then hydrothermal process was applied to produce zinc oxide nanorod arrays. The nanorod thin films were characterized by various spectroscopic methods of analysis. From the images of field emission scanning electron microscope (FESEM, it was observed that for the film thickness up to 200 nm the formed nanorods with wurtzite hexagonal structure were uniformly distributed over the entire surface substrate. From X-ray diffraction analysis it was revealed that the thin films had good polycrystalline nature with highly preferred c-axis orientation along (0 0 2 plane. The optical characterization done by UV-Vis spectrometer showed that all the films had high transparency of 83 % to 96 % in the visible region and sharp cut off at ultraviolet region of electromagnetic spectrum. The band gap of the films decreased as their thickness increased. Energy dispersive X-ray spectroscopy (EDS showed the presence of zinc and oxygen elements in the films and Fourier transform infrared spectroscopy (FT-IR revealed the chemical composition of ZnO in the film.

Normal-incidence spectroscopic ellipsometry for critical dimension monitoring

International Nuclear Information System (INIS)

Huang, Hsu-Ting; Kong, Wei; Terry, Fred Lewis

2001-01-01

In this letter, we show that normal-incidence spectroscopic ellipsometry can be used for high-accuracy topography measurements on surface relief gratings. We present both experimental and theoretical results which show that spectroscopic ellipsometry or reflectance-difference spectroscopy at near-normal incidence coupled with vector diffraction theory for data analysis is capable of high-accuracy critical dimension (CD), feature height, and sidewall angle measurements in the extreme submicron regime. Quantitative comparisons of optical and cross-sectional scanning electron microscopy (SEM) topography measurements from a number of 350 nm line/space reactive-ion-etched Si gratings demonstrate the strong potential for in situ etching monitoring. This technique can be used for both ex situ and in situ applications and has the potential to replace the use of CD-SEM measurements in some applications. [copyright] 2001 American Institute of Physics

PRISM: Processing routines in IDL for spectroscopic measurements (installation manual and user's guide, version 1.0)

Science.gov (United States)

Kokaly, Raymond F.

2011-01-01

This report describes procedures for installing and using the U.S. Geological Survey Processing Routines in IDL for Spectroscopic Measurements (PRISM) software. PRISM provides a framework to conduct spectroscopic analysis of measurements made using laboratory, field, airborne, and space-based spectrometers. Using PRISM functions, the user can compare the spectra of materials of unknown composition with reference spectra of known materials. This spectroscopic analysis allows the composition of the material to be identified and characterized. Among its other functions, PRISM contains routines for the storage of spectra in database files, import/export of ENVI spectral libraries, importation of field spectra, correction of spectra to absolute reflectance, arithmetic operations on spectra, interactive continuum removal and comparison of spectral features, correction of imaging spectrometer data to ground-calibrated reflectance, and identification and mapping of materials using spectral feature-based analysis of reflectance data. This report provides step-by-step instructions for installing the PRISM software and running its functions.

Spectroscopic surveys of LAMOST

International Nuclear Information System (INIS)

Zhao Yongheng

2015-01-01

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST), a new type of reflecting Schmidt telescope, has been designed and produced in China. It marks a breakthrough for large scale spectroscopic survey observation in that both large aperture and wide field of view have been achieved. LAMOST has the highest spectrum acquisition rate, and from October 2011 to June 2014 it has obtained 4.13 million spectra of celestial objects, of which 3.78 million are spectra of stars, with the stellar parameters of 2.20 million stars included. (author)

Spectroscopic analysis of electron trapping levels in pentacene field-effect transistors

International Nuclear Information System (INIS)

Bum Park, Chang

2014-01-01

Electron trapping phenomena have been investigated with respect to the energy levels of localized trap states and bias-induced device instability effects in pentacene field-effect transistors. The mechanism of the photoinduced threshold voltage shift (ΔV T ) is presented by providing a ΔV T model governed by the electron trapping. The trap-and-release behaviour functionalized by photo-irradiation also shows that the trap state for electrons is associated with the energy levels in different positions in the forbidden gap of pentacene. Spectroscopic analysis identifies two kinds of electron trap states distributed above and below the energy of 2.5 eV in the band gap of the pentacene crystal. The study of photocurrent spectra shows the specific trap levels of electrons in energy space that play a substantial role in causing device instability. The shallow and deep trapping states are distributed at two centroidal energy levels of ∼1.8 and ∼2.67 eV in the pentacene band gap. Moreover, we present a systematic energy profile of electron trap states in the pentacene crystal for the first time. (paper)

HITRAN Application Programming Interface (HAPI): A comprehensive approach to working with spectroscopic data

International Nuclear Information System (INIS)

Kochanov, R.V.; Gordon, I.E.; Rothman, L.S.; Wcisło, P.; Hill, C.; Wilzewski, J.S.

2016-01-01

The HITRAN Application Programming Interface (HAPI) is presented. HAPI is a free Python library, which extends the capabilities of the HITRANonline interface ( (www.hitran.org)) and can be used to filter and process the structured spectroscopic data. HAPI incorporates a set of tools for spectra simulation accounting for the temperature, pressure, optical path length, and instrument properties. HAPI is aimed to facilitate the spectroscopic data analysis and the spectra simulation based on the line-by-line data, such as from the HITRAN database [JQSRT (2013) 130, 4–50], allowing the usage of the non-Voigt line profile parameters, custom temperature and pressure dependences, and partition sums. The HAPI functions allow the user to control the spectra simulation and data filtering process via a set of the function parameters. HAPI can be obtained at its homepage (www.hitran.org/hapi). - Highlights: • HAPI extends the HITRANonline portal and provides an access to the HITRAN data. • Free, flexible, and portable Python library for working with the spectroscopic data. • Incorporates functions for querying, filtering and processing the spectroscopic data. • Provides functionality for single-layer spectra simulation. • Can be used in the radiative transfer codes, spectroscopic data validation, etc.

Real time spectroscopic ellipsometry for analysis and control of thin film polycrystalline semiconductor deposition in photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Koirala, Prakash; Attygalle, Dinesh; Aryal, Puruswottam; Pradhan, Puja; Chen, Jie [Center for Photovoltaics Innovation and Commercialization and Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606 (United States); Marsillac, Sylvain [Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, VA 23529 (United States); Ferlauto, Andre S.; Podraza, Nikolas J.; Collins, Robert W. [Center for Photovoltaics Innovation and Commercialization and Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606 (United States)

2014-11-28

Real time spectroscopic ellipsometry (RTSE) from the near-infrared to ultraviolet has been applied for analysis of the deposition of polycrystalline thin films that form the basis of two key photovoltaic heterojunction configurations, superstrate SnO{sub 2}/CdS/CdTe and substrate Mo/Cu(In{sub 1−x}Ga{sub x})Se{sub 2}/CdS. The focus of this work is to develop capabilities for monitoring and controlling the key steps in the fabrication of these device structures. Analysis of RTSE data collected during sputter deposition of CdS on a rough SnO{sub 2} transparent top contact provides the time evolution of the CdS effective thickness, or film volume per unit substrate area. This thickness includes interface, bulk, and surface roughness layer components and affects the CdS/CdTe heterojunction performance and the quantum efficiency of the solar cell in the blue region of the solar spectrum. Similarly, analysis of RTSE data collected during co-evaporation of Cu(In{sub 1−x}Ga{sub x})Se{sub 2} (CIGS; x ∼ 0.3) on a rough Mo back contact provides the evolution of a second phase of Cu{sub 2−x}Se within the CIGS layer. During the last stage of CIGS deposition, the In, Ga, and Se co-evaporants convert this Cu{sub 2−x}Se phase to CIGS, and RTSE identifies the endpoint, specifically the time at which complete conversion occurs and single-phase, large-grain CIGS is obtained in this key stage. - Highlights: • Real time spectroscopic ellipsometry (RTSE) study of CdS and CuIn{sub 1−x}Ga{sub x}Se{sub 2} (CIGS) films. • RTSE during CdS deposition provides the evolution of the CdS effective thickness. • RTSE for CIGS film enables to measure and control the composition and thickness. • The work leads to the development of optical models for processing steps.

THE zCOSMOS 10k-BRIGHT SPECTROSCOPIC SAMPLE

International Nuclear Information System (INIS)

Lilly, Simon J.; Maier, Christian; Carollo, Marcella; Caputi, Karina; Le Brun, Vincent; Kneib, Jean-Paul; Le Fevre, Olivier; De la Torre, Sylvain; De Ravel, Loic; Mainieri, Vincenzo; Mignoli, Marco; Zamorani, Gianni; Bardelli, Sandro; Bolzonella, Micol; Coppa, Graziano; Scodeggio, Marco; Contini, Thierry; Renzini, Alvio; Bongiorno, Angela; Cucciati, Olga

2009-01-01

We present spectroscopic redshifts of a large sample of galaxies with I AB -1 , independent of redshift. The reliability of individual redshifts is described by a Confidence Class that has been empirically calibrated through repeat spectroscopic observations of over 600 galaxies. There is very good agreement between spectroscopic and photometric redshifts for the most secure Confidence Classes. For the less secure Confidence Classes, there is a good correspondence between the fraction of objects with a consistent photometric redshift and the spectroscopic repeatability, suggesting that the photometric redshifts can be used to indicate which of the less secure spectroscopic redshifts are likely right and which are probably wrong, and to give an indication of the nature of objects for which we failed to determine a redshift. Using this approach, we can construct a spectroscopic sample that is 99% reliable and which is 88% complete in the sample as a whole, and 95% complete in the redshift range 0.5 < z < 0.8. The luminosity and mass completeness levels of the zCOSMOS-bright sample of galaxies is also discussed.

Spectroscopic study

International Nuclear Information System (INIS)

Flores, M.; Rodriguez, R.; Arroyo, R.

1999-01-01

This work is focused about the spectroscopic properties of a polymer material which consists of Polyacrylic acid (Paa) doped at different concentrations of Europium ions (Eu 3+ ). They show that to stay chemically joined with the polymer by a study of Nuclear Magnetic Resonance (NMR) of 1 H, 13 C and Fourier Transform Infrared Spectroscopy (Ft-IR) they present changes in the intensity of signals, just as too when this material is irradiated at λ = 394 nm. In according with the results obtained experimentally in this type of materials it can say that is possible to unify chemically the polymer with this type of cations, as well as, varying the concentration of them, since that these are distributed homogeneously inside the matrix maintaining its optical properties. These materials can be obtained more quickly and easy in solid or liquid phase and they have the best conditions for to make a quantitative analysis. (Author)

Spectroscopic identification of rare earth elements in phosphate glass

Science.gov (United States)

Devangad, Praveen; Tamboli, Maktum; Muhammed Shameem, K. M.; Nayak, Rajesh; Patil, Ajeetkumar; Unnikrishnan, V. K.; Santhosh, C.; Kumar, G. A.

2018-01-01

In this work, rare earth-doped phosphate glasses were synthesized and characterized using three different spectroscopic techniques. The absorption spectra of the prepared praseodymium (Pr) and samarium (Sm) doped glasses, recorded by a UV-VIS-NIR spectrophotometer, show the characteristic absorption bands of these elements. To confirm this inference, laser-induced fluorescence spectra of Pr and Sm were obtained at a laser excitation of 442 nm. Their emission bands are reported here. The elemental analysis of these samples was carried out using a laser-induced breakdown spectroscopy (LIBS) system. Characteristic emission lines of Pr and Sm have been identified and reported by the recorded LIBS spectra of glass samples. Results prove that using these three complimentary spectroscopic techniques (absorption, fluorescence and LIBS), we can meaningfully characterize rare earth-doped glass samples.

Automated processing for proton spectroscopic imaging using water reference deconvolution.

Science.gov (United States)

Maudsley, A A; Wu, Z; Meyerhoff, D J; Weiner, M W

1994-06-01

Automated formation of MR spectroscopic images (MRSI) is necessary before routine application of these methods is possible for in vivo studies; however, this task is complicated by the presence of spatially dependent instrumental distortions and the complex nature of the MR spectrum. A data processing method is presented for completely automated formation of in vivo proton spectroscopic images, and applied for analysis of human brain metabolites. This procedure uses the water reference deconvolution method (G. A. Morris, J. Magn. Reson. 80, 547(1988)) to correct for line shape distortions caused by instrumental and sample characteristics, followed by parametric spectral analysis. Results for automated image formation were found to compare favorably with operator dependent spectral integration methods. While the water reference deconvolution processing was found to provide good correction of spatially dependent resonance frequency shifts, it was found to be susceptible to errors for correction of line shape distortions. These occur due to differences between the water reference and the metabolite distributions.

Spectroscopic analysis of radiation-generated changes in tensile properties of a polyetherimide film

International Nuclear Information System (INIS)

Long, E.R. Jr.; Long, S.A.T.

1985-05-01

The effects of electron radiation on Ultem, a polyetherimide were studied for doses from 2 x 10 to the 9th power to 6 x 10 to the 9th power rad. Specimens were studied for tensile property testing and for electron paramagnetic resonance and infrared spectroscopic measurements of molecular structure. A Faraday cup design and a method for remote temperature measurement were developed. The spectroscopic data show that radiation caused dehydrogenation of methyl groups, rupture of main-chain ether linkage, and opening of imide rings, all to form radicals and indicate that the so-formed atomic hydrogen attached to phenyl radicals, but not to phenoxyl radicals, which would have formed hydroxyls. The observed decays of the radiation-generated phenoxyl, gem-dimethyl, and carbonyl radicals were interpreted as a combining of the radicals to form crosslinking. This crosslinking is the probable cause of the major reduction in the elongation of the tensile specimens after irradiation. Subsequent classical solubility tests indicate that the irradiation caused massive crosslinking

Spectroscopic analysis of PMMA/PVC blends containing CoCl2

Directory of Open Access Journals (Sweden)

N.S. Alghunaim

2015-01-01

Full Text Available Composites of polymethyl methacrylate (PMMA and polyvinyl chloride (PVC polymer blend containing different concentrations (⩽10 wt. of cobalt chloride (CoCl2 were prepared by casting techniques. The changes of the structural, spectroscopic, optical and thermal parameters of the samples are studied using different tools. FT-IR spectroscopy confirmed the complexation between the blends and Co+2-ions. The decrease or increase of IR band intensity with some shifts of other bands suggests an interaction and compatibility between PMMA/PVC blends with CoCl2 take place. The Ultra violet and visible (UV/Vis spectra indicated that the presence of band gap energy depends on increasing of CoCl2 contents. The absorption intensity of the samples doped with CoCl2 becomes faint lower than the pure blend. The values of energy gap for direct and indirect transition decreases with the increase of CoCl2 due to the presence of charge transfer between PMMA/PVC and CoCl2. The thermogravimetric analysis (TGA curves for all the samples have the same behavior and more steps of decomposition were observed. The reduction of mass loss for samples containing CoCl2 compared to the pure blend was observed and it was attributed to crosslink formation between the blend and CoCl2.

Spectroscopic methods for detection of impurities in water

Science.gov (United States)

Strashnikova, Natalia V.; Papiashvili, Nona; Cohen-Luria, Rivka; Mark, Shlomo; Shilon, Guy; Khankin, Daniel; Kalisky, Yehoshua; Kalisky, Ofra; Parola, Abraham H.

2011-11-01

Optical photoluminescence spectroscopic method for detection of impurities, hazardous materials, pesticides, and pollutants in water resources, both qualitatively and quantitatively, is presented. The method is based on synchronous fluorescence spectroscopy (SFS) of organic aromatic compounds, or poly-aromatic hydrocarbons (PAH), and is carried out by following simultaneously their excitation and emission spectra. The full excitation emission matrix (EEM) generated in this way provides a 2-D and 3-D fluorescence map of the tested sample and the diagonals through the axes origin provide the synchronous fluorescence spectra at a constant wavelengths differences between the emission and excitation wavelengths, thus enabling multitude components identification. This map contains all the relevant spectroscopic information of the tested sample, and serves as a unique "fingerprint" with a very specific and accurate identification. When compared with pre-determined spectra and calibration curves from a "databank", there is a one-toone correspondence between the image and the specific compound, and it can be identified accurately both qualitatively and quantitatively. This method offers several significant advantages, and it provides a sensitive (ppm detection level), accurate and simple spectroscopic tool to monitor impurities and pollutants in water. The design and performance of the spectrofluorimeter prototype, as well as the software development and analysis of chemical organic compounds and mixtures in water will be discussed in this paper.

IR and UV spectroscopic analysis of TBP complexes

International Nuclear Information System (INIS)

Azzouz, A.; Berrak, A.; Seridi, L.; Attou, M.

1985-06-01

The complexity of TBP molecule and the limited number of references stimulated the elaboration of this report. The spectroscopic of TBP and its complexes in the IR and UV fields permitted to elucidate or to confirm certain aspects concerning the solvation phenomenum. In IR spectroscopy, the stretching band of the P→O bond only is characteristic of the complex formed. The position of this band gives sufficient information about the kind and the stability of a complex. The TBP electronic spectra are characterized by two bands (200-220 nm) 1 and (268-290 nm) 2 whose intensity ratio (2/1) is about 0,13. The solvent nature seems to influence the positions of these bands and that of the inflexion point. The band 2 disappears when the TBP is complexed and the position and the intensity of the band 1 depend upon the complex nature

Combining sequence-based prediction methods and circular dichroism and infrared spectroscopic data to improve protein secondary structure determinations

Directory of Open Access Journals (Sweden)

Lees Jonathan G

2008-01-01

Full Text Available Abstract Background A number of sequence-based methods exist for protein secondary structure prediction. Protein secondary structures can also be determined experimentally from circular dichroism, and infrared spectroscopic data using empirical analysis methods. It has been proposed that comparable accuracy can be obtained from sequence-based predictions as from these biophysical measurements. Here we have examined the secondary structure determination accuracies of sequence prediction methods with the empirically determined values from the spectroscopic data on datasets of proteins for which both crystal structures and spectroscopic data are available. Results In this study we show that the sequence prediction methods have accuracies nearly comparable to those of spectroscopic methods. However, we also demonstrate that combining the spectroscopic and sequences techniques produces significant overall improvements in secondary structure determinations. In addition, combining the extra information content available from synchrotron radiation circular dichroism data with sequence methods also shows improvements. Conclusion Combining sequence prediction with experimentally determined spectroscopic methods for protein secondary structure content significantly enhances the accuracy of the overall results obtained.

APPLYING SPECTROSCOPIC METHODS ON ANALYSES OF HAZARDOUS WASTE

OpenAIRE

Dobrinić, Julijan; Kunić, Marija; Ciganj, Zlatko

2000-01-01

Abstract The paper presents results of measuring the content of heavy and other metals in waste samples from the hazardous waste disposal site of Sovjak near Rijeka. The preliminary design elaboration and the choice of the waste disposal sanification technology were preceded by the sampling and physico-chemical analyses of disposed waste, enabling its categorization. The following spectroscopic methods were applied on metal content analysis: Atomic absorption spectroscopy (AAS) and plas...

Spectroscopic studies on surface reactions between minerals and reagents in flotation systems

International Nuclear Information System (INIS)

Giesekke, E.W.

1981-01-01

A study of the adsorbed species at the interface between the minerals and the aqueous solution is reported in the hope that it will contribute to a better understanding of selective mineral flotation by various reagents. The results of infrared spectroscopic studies are cited from the author's investigation on the fluorite-sodium oleate and fluorite-linoleate systems. Electron-spectroscopic techniques, e.g., electron spectroscopy for chemical analysis (ESCA) have also been useful in the identification of adsorbed species on mineral surfaces. Some experimental data from the literature are discussed. These studies have the disadvantage that they are not in situ investigations of the interface between the mineral and the aqueous solution. The potential use of other spectroscopic techniques are discussed, photo-acoustic, Raman, and electron-spin-resonance spectroscopy being considered as possible alternatives. It is suggested that the relatively small surface areas of minerals used in flotation (i.e. smaller than 2m 2 .g- 1 ) impose severe restrictions on the use of such techniques

Detection and Monitoring of Neurotransmitters - a Spectroscopic Analysis

Science.gov (United States)

Manciu, Felicia; Lee, Kendall; Durrer, William; Bennet, Kevin

2012-10-01

In this work we demonstrate the capability of confocal Raman mapping spectroscopy for simultaneously and locally detecting important compounds in neuroscience such as dopamine, serotonin, and adenosine. The Raman results show shifting of the characteristic vibrations of the compounds, observations consistent with previous spectroscopic studies. Although some vibrations are common in these neurotransmitters, Raman mapping was achieved by detecting non-overlapping characteristic spectral signatures of the compounds, as follows: for dopamine the vibration attributed to C-O stretching, for serotonin the indole ring stretching vibration, and for adenosine the adenine ring vibrations. Without damage, dyeing, or preferential sample preparation, confocal Raman mapping provided positive detection of each neurotransmitter, allowing association of the high-resolution spectra with specific micro-scale image regions. Such information is particularly important for complex, heterogeneous samples, where modification of the chemical or physical composition can influence the neurotransmission processes. We also report an estimated dopamine diffusion coefficient two orders of magnitude smaller than that calculated by the flow-injection method.

Raman Spectroscopic Studies of Methane Gas Hydrates

DEFF Research Database (Denmark)

Hansen, Susanne Brunsgaard; Berg, Rolf W.

2009-01-01

A brief review of the Raman spectroscopic studies of methane gas hydrates is given, supported by some new measurements done in our laboratory.......A brief review of the Raman spectroscopic studies of methane gas hydrates is given, supported by some new measurements done in our laboratory....

Multi-pass spectroscopic ellipsometry

International Nuclear Information System (INIS)

Stehle, Jean-Louis; Samartzis, Peter C.; Stamataki, Katerina; Piel, Jean-Philippe; Katsoprinakis, George E.; Papadakis, Vassilis; Schimowski, Xavier; Rakitzis, T. Peter; Loppinet, Benoit

2014-01-01

Spectroscopic ellipsometry is an established technique, particularly useful for thickness measurements of thin films. It measures polarization rotation after a single reflection of a beam of light on the measured substrate at a given incidence angle. In this paper, we report the development of multi-pass spectroscopic ellipsometry where the light beam reflects multiple times on the sample. We have investigated both theoretically and experimentally the effect of sample reflectivity, number of reflections (passes), angles of incidence and detector dynamic range on ellipsometric observables tanΨ and cosΔ. The multiple pass approach provides increased sensitivity to small changes in Ψ and Δ, opening the way for single measurement determination of optical thickness T, refractive index n and absorption coefficient k of thin films, a significant improvement over the existing techniques. Based on our results, we discuss the strengths, the weaknesses and possible applications of this technique. - Highlights: • We present multi-pass spectroscopic ellipsometry (MPSE), a multi-pass approach to ellipsometry. • Different detectors, samples, angles of incidence and number of passes were tested. • N passes improve polarization ratio sensitivity to the power of N. • N reflections improve phase shift sensitivity by a factor of N. • MPSE can significantly improve thickness measurements in thin films

Raman Spectroscopic Imaging of the Whole Ciona intestinalis Embryo during Development

Science.gov (United States)

Nakamura, Mitsuru J.; Hotta, Kohji; Oka, Kotaro

2013-01-01

Intracellular composition and the distribution of bio-molecules play central roles in the specification of cell fates and morphogenesis during embryogenesis. Consequently, investigation of changes in the expression and distribution of bio-molecules, especially mRNAs and proteins, is an important challenge in developmental biology. Raman spectroscopic imaging, a non-invasive and label-free technique, allows simultaneous imaging of the intracellular composition and distribution of multiple bio-molecules. In this study, we explored the application of Raman spectroscopic imaging in the whole Ciona intestinalis embryo during development. Analysis of Raman spectra scattered from C. intestinalis embryos revealed a number of localized patterns of high Raman intensity within the embryo. Based on the observed distribution of bio-molecules, we succeeded in identifying the location and structure of differentiated muscle and endoderm within the whole embryo, up to the tailbud stage, in a label-free manner. Furthermore, during cell differentiation, we detected significant differences in cell state between muscle/endoderm daughter cells and daughter cells with other fates that had divided from the same mother cells; this was achieved by focusing on the Raman intensity of single Raman bands at 1002 or 1526 cm−1, respectively. This study reports the first application of Raman spectroscopic imaging to the study of identifying and characterizing differentiating tissues in a whole chordate embryo. Our results suggest that Raman spectroscopic imaging is a feasible label-free technique for investigating the developmental process of the whole embryo of C. intestinalis. PMID:23977129

Spectroscopic analysis and molecular docking of imidazole derivatives and investigation of its reactive properties by DFT and molecular dynamics simulations

Science.gov (United States)

Thomas, Renjith; Hossain, Mossaraf; Mary, Y. Sheena; Resmi, K. S.; Armaković, Stevan; Armaković, Sanja J.; Nanda, Ashis Kumar; Ranjan, Vivek Kumar; Vijayakumar, G.; Van Alsenoy, C.

2018-04-01

Solvent-free synthesis pathway for obtaining two imidazole derivatives (2-chloro-1-(4-methoxyphenyl)-4,5-dimethyl-1H-imidazole (CLMPDI) and 1-(4-bromophenyl)-2-chloro-4,5-dimethyl-1H-imidazole (BPCLDI) has been reported in this work, followed by detailed experimental and computational spectroscopic characterization and reactivity study. Spectroscopic methods encompassed IR, FT-Raman and NMR techniques, with the mutual comparison of experimentally and computationally obtained results at DFT/B3LYP level of theory. Reactivity study based on DFT calculations encompassed molecular orbitals analysis, followed by calculations of molecular electrostatic potential (MEP) and average local ionization energy (ALIE) values, Fukui functions and bond dissociation energies (BDE). Additionally, the stability of title molecules in water has been investigated via molecular dynamics (MD) simulations, while interactivity with aspulvinonedimethylallyl transferase protein has been evaluated by molecular docking procedure. CLMPDI compound showed antimicrobial activity against all four bacterial strain in both gram positive and gram negative bacteria while, BPCLDI showed only in gram positive bacteria, Staphylococcus Aureus (MTCC1144). The first order hyperpolarizability of CLMPDI and BPCLDI are 20.15 and 6.10 times that of the standard NLO material urea.

Interaction of tea polyphenols with serum albumins: A fluorescence spectroscopic analysis

Energy Technology Data Exchange (ETDEWEB)

Bose, Adity, E-mail: adityc17j@gmail.com

2016-01-15

Interactions of some tea polyphenols, namely (−) Catechin (C), (−)-epicatechin (EC), (–) epicatechin-3-gallate (ECG), (−)-epigallocatechin (EGC) and (−)-epigallocatechin-3-gallate (EGCG) are outlined with the serum albumin proteins. These interactions had all resulted in binding with the proteins with a concomitant static quenching of the protein fluorescence. A fluorescence technique has been considered as the tool to comprehend the polyphenol–protein interactions mainly and simultaneously other spectroscopic techniques used to verify the results have been discussed. In this mini review the different types of equations usually employed to calculate the binding constant values have been outlined, namely, modified Stern Volmer plot, Scatchard plot and Lineweaver Burk equation, with their corresponding results. The n values (number of binding sites) had always been close to unity suggesting a 1:1 complexation with the polyphenols and the protein. A structural change in the polyphenols has been found to alter the binding constant value and the galloyl moiety attached to the C ring of the polyphenols have been found to play a crucial role in this regard. It has been found that an increase in galloyl moiety increases binding of the catechins with proteins. - Highlights: • Review on interactions of some tea polyphenols with the serum albumin proteins. • Tea polyphenols include Catechin, epigallocatechin-3-gallate, epigallocatechin, epicatechin-3-gallate and epicatechin. • Fluorescence spectroscopic technique is mainly outlined. • Binding constant studies have been given importance. • Galloyl moiety in the C ring is crucial in increasing binding constant.

THE TIME DOMAIN SPECTROSCOPIC SURVEY: VARIABLE SELECTION AND ANTICIPATED RESULTS

Energy Technology Data Exchange (ETDEWEB)

Morganson, Eric; Green, Paul J. [Harvard Smithsonian Center for Astrophysics, 60 Garden St, Cambridge, MA 02138 (United States); Anderson, Scott F.; Ruan, John J. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Eracleous, Michael; Brandt, William Nielsen [Department of Astronomy and Astrophysics, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA 16802 (United States); Kelly, Brandon [Department of Physics, Broida Hall, University of California, Santa Barbara, CA 93106-9530 (United States); Badenes, Carlos [Department of Physics and Astronomy and Pittsburgh Particle Physics, Astrophysics and Cosmology Center (PITT PACC), University of Pittsburgh, 3941 O’Hara St, Pittsburgh, PA 15260 (United States); Bañados, Eduardo [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Blanton, Michael R. [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Bershady, Matthew A. [Department of Astronomy, University of Wisconsin, 475 N. Charter St., Madison, WI 53706 (United States); Borissova, Jura [Instituto de Física y Astronomía, Universidad de Valparaíso, Av. Gran Bretaña 1111, Playa Ancha, Casilla 5030, and Millennium Institute of Astrophysics (MAS), Santiago (Chile); Burgett, William S. [GMTO Corp, Suite 300, 251 S. Lake Ave, Pasadena, CA 91101 (United States); Chambers, Kenneth, E-mail: emorganson@cfa.harvard.edu [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); and others

2015-06-20

We present the selection algorithm and anticipated results for the Time Domain Spectroscopic Survey (TDSS). TDSS is an Sloan Digital Sky Survey (SDSS)-IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) subproject that will provide initial identification spectra of approximately 220,000 luminosity-variable objects (variable stars and active galactic nuclei across 7500 deg{sup 2} selected from a combination of SDSS and multi-epoch Pan-STARRS1 photometry. TDSS will be the largest spectroscopic survey to explicitly target variable objects, avoiding pre-selection on the basis of colors or detailed modeling of specific variability characteristics. Kernel Density Estimate analysis of our target population performed on SDSS Stripe 82 data suggests our target sample will be 95% pure (meaning 95% of objects we select have genuine luminosity variability of a few magnitudes or more). Our final spectroscopic sample will contain roughly 135,000 quasars and 85,000 stellar variables, approximately 4000 of which will be RR Lyrae stars which may be used as outer Milky Way probes. The variability-selected quasar population has a smoother redshift distribution than a color-selected sample, and variability measurements similar to those we develop here may be used to make more uniform quasar samples in large surveys. The stellar variable targets are distributed fairly uniformly across color space, indicating that TDSS will obtain spectra for a wide variety of stellar variables including pulsating variables, stars with significant chromospheric activity, cataclysmic variables, and eclipsing binaries. TDSS will serve as a pathfinder mission to identify and characterize the multitude of variable objects that will be detected photometrically in even larger variability surveys such as Large Synoptic Survey Telescope.

Purged window apparatus. [On-line spectroscopic analysis of gas flow systems

Science.gov (United States)

Ballard, E.O.

1982-04-05

A purged window apparatus is described which utilizes tangentially injected heated purge gases in the vicinity of electromagnetic radiation transmitting windows and a tapered external mounting tube to accelerate these gases to provide a vortex flow on the window surface and a turbulent flow throughout the mounting tube thereby preventing backstreaming of flowing gases under investigation in a chamber to which a plurality of similar purged apparatus is attached with the consequent result that spectroscopic analyses can be undertaken for lengthy periods without the necessity of interrupting the flow for cleaning or replacing the windows due to contamination.

THE BARYON OSCILLATION SPECTROSCOPIC SURVEY OF SDSS-III

Energy Technology Data Exchange (ETDEWEB)

Dawson, Kyle S.; Ahn, Christopher P.; Bolton, Adam S. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Schlegel, David J.; Bailey, Stephen [Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720 (United States); Anderson, Scott F.; Bhardwaj, Vaishali [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Aubourg, Eric; Bautista, Julian E. [APC, University of Paris Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cite (France); Barkhouser, Robert H. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Beifiori, Alessandra [Max-Planck-Institut fuer Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Berlind, Andreas A. [Department of Physics and Astronomy, Vanderbilt University, VU Station 1807, Nashville, TN 37235 (United States); Bizyaev, Dmitry; Brewington, Howard [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349 (United States); Blake, Cullen H. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Blanton, Michael R. [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Blomqvist, Michael [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Borde, Arnaud [CEA, Centre de Saclay, Irfu/SPP, F-91191 Gif-sur-Yvette (France); Bovy, Jo [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States); Brandt, W. N., E-mail: kdawson@astro.utah.edu [Department of Astronomy and Astrophysics, 525 Davey Laboratory, The Pennsylvania State University, University Park, PA 16802 (United States); and others

2013-01-01

The Baryon Oscillation Spectroscopic Survey (BOSS) is designed to measure the scale of baryon acoustic oscillations (BAO) in the clustering of matter over a larger volume than the combined efforts of all previous spectroscopic surveys of large-scale structure. BOSS uses 1.5 million luminous galaxies as faint as i = 19.9 over 10,000 deg{sup 2} to measure BAO to redshifts z < 0.7. Observations of neutral hydrogen in the Ly{alpha} forest in more than 150,000 quasar spectra (g < 22) will constrain BAO over the redshift range 2.15 < z < 3.5. Early results from BOSS include the first detection of the large-scale three-dimensional clustering of the Ly{alpha} forest and a strong detection from the Data Release 9 data set of the BAO in the clustering of massive galaxies at an effective redshift z = 0.57. We project that BOSS will yield measurements of the angular diameter distance d{sub A} to an accuracy of 1.0% at redshifts z = 0.3 and z = 0.57 and measurements of H(z) to 1.8% and 1.7% at the same redshifts. Forecasts for Ly{alpha} forest constraints predict a measurement of an overall dilation factor that scales the highly degenerate D{sub A} (z) and H {sup -1}(z) parameters to an accuracy of 1.9% at z {approx} 2.5 when the survey is complete. Here, we provide an overview of the selection of spectroscopic targets, planning of observations, and analysis of data and data quality of BOSS.

Spectroscopic failures in photometric redshift calibration: cosmological biases and survey requirements

Energy Technology Data Exchange (ETDEWEB)

Cunha, Carlos E. [KIPAC, Menlo Park; Huterer, Dragan [Michigan U.; Lin, Huan [Fermilab; Busha, Michael T. [Zurich U.; Wechsler, Risa H. [SLAC

2014-10-11

We use N-body-spectro-photometric simulations to investigate the impact of incompleteness and incorrect redshifts in spectroscopic surveys to photometric redshift training and calibration and the resulting effects on cosmological parameter estimation from weak lensing shear-shear correlations. The photometry of the simulations is modeled after the upcoming Dark Energy Survey and the spectroscopy is based on a low/intermediate resolution spectrograph with wavelength coverage of 5500{\\AA} < {\\lambda} < 9500{\\AA}. The principal systematic errors that such a spectroscopic follow-up encounters are incompleteness (inability to obtain spectroscopic redshifts for certain galaxies) and wrong redshifts. Encouragingly, we find that a neural network-based approach can effectively describe the spectroscopic incompleteness in terms of the galaxies' colors, so that the spectroscopic selection can be applied to the photometric sample. Hence, we find that spectroscopic incompleteness yields no appreciable biases to cosmology, although the statistical constraints degrade somewhat because the photometric survey has to be culled to match the spectroscopic selection. Unfortunately, wrong redshifts have a more severe impact: the cosmological biases are intolerable if more than a percent of the spectroscopic redshifts are incorrect. Moreover, we find that incorrect redshifts can also substantially degrade the accuracy of training set based photo-z estimators. The main problem is the difficulty of obtaining redshifts, either spectroscopically or photometrically, for objects at z > 1.3. We discuss several approaches for reducing the cosmological biases, in particular finding that photo-z error estimators can reduce biases appreciably.

Spectroscopic factor of the 7He ground state

International Nuclear Information System (INIS)

Beck, F.; Frekers, D.; Neumann-Cosel, P. von; Richter, A.; Ryezayeva, N.; Thompson, I.J.

2007-01-01

The neutron spectroscopic factor S n of the 7 He ground state is extracted from an R-matrix analysis of a recent measurement of the 7 Li(d, 2 He) 7 He reaction with good energy resolution. The width extracted from a deconvolution of the spectrum is Γ=183(22) keV (full width at half maximum, FWHM). The result S n =0.64(9) is slightly larger than predictions of recent 'ab initio' Green's function Monte Carlo and fermionic molecular dynamics calculations

Spectroscopic and corpuscular analysis of laser-produced carbon plasma

International Nuclear Information System (INIS)

Czarnecka, A.; Kubkowska, M.; Kowalska-Strzeciwilk, E.; Parys, P.; Sadowski, M.J.; Skladnik-Sadowska, E.; Malinowski, K.; Kwiatkowski, R.; Ladygina, M.

2013-01-01

The paper describes spectroscopic and corpuscular measurements of laser-produced carbon plasma, which was created at surfaces of three targets made of CFC of the Snecma-N11 type with different crystallographic orientations. In order to irradiate the investigated samples the use was made of a Nd:YAG laser. Experiments were performed in a vacuum chamber under the initial pressure equal to 5.10-5 mbar. A Mechelle 900 optical spectrometer equipped with a CCD detector was used to record spectra emitted from the produced carbon-plasma. The recorded optical spectra showed distinct carbon lines ranging from CI to CIV. Basing on the Stark broadening of the CII 426.7 nm line it was possible to estimate the electron density of plasma from each investigated sample. Corpuscular measurements of the emitted ions were carried out by means of an electrostatic ion-energy analyzer and ion collector.

Spectroscopic studies with the use of deep-inelastic heavy-ion reactions

International Nuclear Information System (INIS)

Broda, R

2006-01-01

Gamma spectroscopic studies exploiting deep-inelastic heavy-ion reactions in thick target experiments are reviewed. The description of physical motivation, history of early experiments, analysis of the N/Z equilibration process as well as the outline of the experimental method and data analysis are followed by the presentation of main results obtained in various regions of the nuclide chart. Brief comments on thin target spectroscopy experiments involving fragment detection and future outlook are summarized. (topical review)

Spectroscopic ellipsometry and polarimetry for materials and systems analysis at the nanometer scale: state-of-the-art, potential, and perspectives

Energy Technology Data Exchange (ETDEWEB)

Losurdo, Maria, E-mail: maria.losurdo@ba.imip.cnr.i [National Council of Research-Institute of Inorganic Methodologies and of Plasmas, CNR-IMIP (Italy); Bergmair, Michael [Johannes Kepler University Linz, Christian Doppler Laboratory for Surface Optics, Center for Surface- and Nanoanalytics (Austria); Bruno, Giovanni [National Council of Research-Institute of Inorganic Methodologies and of Plasmas, CNR-IMIP (Italy); Cattelan, Denis, E-mail: denis.cattelan@horiba.co [HORIBA Scientific, Thin Film Division (France); Cobet, Christoph [ISAS Institute for Analytical Sciences, Department Berlin (Germany); Martino, Antonello de [Ecole Polytechnique, Centre National de la Recherche Scientique (CNRS-LPICM) (France); Fleischer, Karsten [ISAS Institute for Analytical Sciences, Department Berlin (Germany); Dohcevic-Mitrovic, Zorana [Institute of Physics, Center for Solid State Physics and New Materials (Serbia); Esser, Norbert [ISAS Institute for Analytical Sciences, Department Berlin (Germany); Galliet, Melanie, E-mail: melanie.gaillet@horiba.co [HORIBA Scientific, Thin Film Division (France); Gajic, Rados [Institute of Physics, Center for Solid State Physics and New Materials (Serbia); Hemzal, Dusan; Hingerl, Kurt [Johannes Kepler University Linz, Christian Doppler Laboratory for Surface Optics, Center for Surface- and Nanoanalytics (Austria); Humlicek, Josef; Ossikovski, Razvigor [Ecole Polytechnique, Centre National de la Recherche Scientique (CNRS-LPICM) (France); Popovic, Zoran V. [Institute of Physics, Center for Solid State Physics and New Materials (Serbia); Saxl, Ottilia [Institute of Nanotechnology (United Kingdom)

2009-10-15

This paper discusses the fundamentals, applications, potential, limitations, and future perspectives of polarized light reflection techniques for the characterization of materials and related systems and devices at the nanoscale. These techniques include spectroscopic ellipsometry, polarimetry, and reflectance anisotropy. We give an overview of the various ellipsometry strategies for the measurement and analysis of nanometric films, metal nanoparticles and nanowires, semiconductor nanocrystals, and submicron periodic structures. We show that ellipsometry is capable of more than the determination of thickness and optical properties, and it can be exploited to gain information about process control, geometry factors, anisotropy, defects, and quantum confinement effects of nanostructures.

Spectroscopic ellipsometry and polarimetry for materials and systems analysis at the nanometer scale: state-of-the-art, potential, and perspectives

International Nuclear Information System (INIS)

Losurdo, Maria; Bergmair, Michael; Bruno, Giovanni; Cattelan, Denis; Cobet, Christoph; Martino, Antonello de; Fleischer, Karsten; Dohcevic-Mitrovic, Zorana; Esser, Norbert; Galliet, Melanie; Gajic, Rados; Hemzal, Dusan; Hingerl, Kurt; Humlicek, Josef; Ossikovski, Razvigor; Popovic, Zoran V.; Saxl, Ottilia

2009-01-01

This paper discusses the fundamentals, applications, potential, limitations, and future perspectives of polarized light reflection techniques for the characterization of materials and related systems and devices at the nanoscale. These techniques include spectroscopic ellipsometry, polarimetry, and reflectance anisotropy. We give an overview of the various ellipsometry strategies for the measurement and analysis of nanometric films, metal nanoparticles and nanowires, semiconductor nanocrystals, and submicron periodic structures. We show that ellipsometry is capable of more than the determination of thickness and optical properties, and it can be exploited to gain information about process control, geometry factors, anisotropy, defects, and quantum confinement effects of nanostructures.

Fundamental spectroscopic studies of carbenes and hydrocarbon radicals

Energy Technology Data Exchange (ETDEWEB)

Gottlieb, C.A.; Thaddeus, P. [Harvard Univ., Cambridge, MA (United States)

1993-12-01

Highly reactive carbenes and carbon-chain radicals are studied at millimeter wavelengths by observing their rotational spectra. The purpose is to provide definitive spectroscopic identification, accurate spectroscopic constants in the lowest vibrational states, and reliable structures of the key intermediates in reactions leading to aromatic hydrocarbons and soot particles in combustion.

NMR spectroscopic and analytical ultracentrifuge analysis of membrane protein detergent complexes

Directory of Open Access Journals (Sweden)

Choe Senyon

2007-11-01

Full Text Available Abstract Background Structural studies of integral membrane proteins (IMPs are hampered by inherent difficulties in their heterologous expression and in the purification of solubilized protein-detergent complexes (PDCs. The choice and concentrations of detergents used in an IMP preparation play a critical role in protein homogeneity and are thus important for successful crystallization. Results Seeking an effective and standardized means applicable to genomic approaches for the characterization of PDCs, we chose 1D-NMR spectroscopic analysis to monitor the detergent content throughout their purification: protein extraction, detergent exchange, and sample concentration. We demonstrate that a single NMR measurement combined with a SDS-PAGE of a detergent extracted sample provides a useful gauge of the detergent's extraction potential for a given protein. Furthermore, careful monitoring of the detergent content during the process of IMP production allows for a high level of reproducibility. We also show that in many cases a simple sedimentation velocity measurement provides sufficient data to estimate both the oligomeric state and the detergent-to-protein ratio in PDCs, as well as to evaluate the homogeneity of the samples prior to crystallization screening. Conclusion The techniques presented here facilitate the screening and selection of the extraction detergent, as well as help to maintain reproducibility in the detergent exchange and PDC concentration procedures. Such reproducibility is particularly important for the optimization of initial crystallization conditions, for which multiple purifications are routinely required.

Structure and spectroscopic properties of neutral and cationic tetratomic [C,H,N,Zn] isomers: A theoretical study

Science.gov (United States)

Redondo, Pilar; Largo, Antonio; Vega-Vega, Álvaro; Barrientos, Carmen

2015-05-01

The structure and spectroscopic parameters of the most relevant [C,H,N,Zn] isomers have been studied employing high-level quantum chemical methods. For each isomer, we provide predictions for their molecular structure, thermodynamic stabilities as well as vibrational and rotational spectroscopic parameters which could eventually help in their experimental detection. In addition, we have carried out a detailed study of the bonding situations by means of a topological analysis of the electron density in the framework of the Bader's quantum theory of atoms in molecules. The analysis of the relative stabilities and spectroscopic parameters suggests two linear isomers of the neutral [C,H,N,Zn] composition, namely, cyanidehydridezinc HZnCN (1Σ) and hydrideisocyanidezinc HZnNC (1Σ), as possible candidates for experimental detections. For the cationic [C,H,N,Zn]+ composition, the most stable isomers are the ion-molecule complexes arising from the direct interaction of the zinc cation with either the nitrogen or carbon atom of either hydrogen cyanide or hydrogen isocyanide, namely, HCNZn+ (2Σ) and HCNZn+ (2Σ).

Structure and spectroscopic properties of neutral and cationic tetratomic [C,H,N,Zn] isomers: A theoretical study

International Nuclear Information System (INIS)

Redondo, Pilar; Largo, Antonio; Vega-Vega, Álvaro; Barrientos, Carmen

2015-01-01

The structure and spectroscopic parameters of the most relevant [C,H,N,Zn] isomers have been studied employing high-level quantum chemical methods. For each isomer, we provide predictions for their molecular structure, thermodynamic stabilities as well as vibrational and rotational spectroscopic parameters which could eventually help in their experimental detection. In addition, we have carried out a detailed study of the bonding situations by means of a topological analysis of the electron density in the framework of the Bader’s quantum theory of atoms in molecules. The analysis of the relative stabilities and spectroscopic parameters suggests two linear isomers of the neutral [C,H,N,Zn] composition, namely, cyanidehydridezinc HZnCN ( 1 Σ) and hydrideisocyanidezinc HZnNC ( 1 Σ), as possible candidates for experimental detections. For the cationic [C,H,N,Zn] + composition, the most stable isomers are the ion-molecule complexes arising from the direct interaction of the zinc cation with either the nitrogen or carbon atom of either hydrogen cyanide or hydrogen isocyanide, namely, HCNZn + ( 2 Σ) and HCNZn + ( 2 Σ)

Structure and spectroscopic properties of neutral and cationic tetratomic [C,H,N,Zn] isomers: A theoretical study

Energy Technology Data Exchange (ETDEWEB)

Redondo, Pilar; Largo, Antonio; Vega-Vega, Álvaro; Barrientos, Carmen, E-mail: cbb@qf.uva.es [Departamento de Química Física y Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid, 47011 Valladolid (Spain)

2015-05-14

The structure and spectroscopic parameters of the most relevant [C,H,N,Zn] isomers have been studied employing high-level quantum chemical methods. For each isomer, we provide predictions for their molecular structure, thermodynamic stabilities as well as vibrational and rotational spectroscopic parameters which could eventually help in their experimental detection. In addition, we have carried out a detailed study of the bonding situations by means of a topological analysis of the electron density in the framework of the Bader’s quantum theory of atoms in molecules. The analysis of the relative stabilities and spectroscopic parameters suggests two linear isomers of the neutral [C,H,N,Zn] composition, namely, cyanidehydridezinc HZnCN ({sup 1}Σ) and hydrideisocyanidezinc HZnNC ({sup 1}Σ), as possible candidates for experimental detections. For the cationic [C,H,N,Zn]{sup +} composition, the most stable isomers are the ion-molecule complexes arising from the direct interaction of the zinc cation with either the nitrogen or carbon atom of either hydrogen cyanide or hydrogen isocyanide, namely, HCNZn{sup +} ({sup 2}Σ) and HCNZn{sup +} ({sup 2}Σ)

Optical constants of graphene measured by spectroscopic ellipsometry

NARCIS (Netherlands)

Weber, J.W.; Calado, V.E.; Van de Sanden, M.C.M.

2010-01-01

A mechanically exfoliated graphene flake ( ? 150×380??m2) on a silicon wafer with 98 nm silicon dioxide on top was scanned with a spectroscopic ellipsometer with a focused spot ( ? 100×55??m2) at an angle of 55°. The spectroscopic ellipsometric data were analyzed with an optical model in which the

Optical constants of graphene measured by spectroscopic ellipsometry

NARCIS (Netherlands)

Weber, J.W.; Calado, V.E.; Sanden, van de M.C.M.

2010-01-01

A mechanically exfoliated graphene flake ( ~ 150×380 µm2) on a silicon wafer with 98 nm silicon dioxide on top was scanned with a spectroscopic ellipsometer with a focused spot ( ~ 100×55 µm2) at an angle of 55°. The spectroscopic ellipsometric data were analyzed with an optical model in which the

Spectroscopic Tools for Quantitative Studies of DNA Structure and Dynamics

DEFF Research Database (Denmark)

Preus, Søren

The main objective of this thesis is to develop quantitative fluorescence-based, spectroscopic tools for probing the 3D structure and dynamics of DNA and RNA. The thesis is founded on six peer-reviewed papers covering mainly the development, characterization and use of fluorescent nucleobase...... analogues. In addition, four software packages is presented for the simulation and quantitative analysis of time-resolved and steady-state UV-Vis absorption and fluorescence experiments....

Spectroscopic determination of anthraquinone in kraft pulping liquors using a membrane interface

Science.gov (United States)

X.S. Chai; X.T. Yang; Q.X. Hou; J.Y. Zhu; L.-G. Danielsson

2003-01-01

A spectroscopic technique for determining AQ in pulping liquor was developed to effectively separate AQ from dissolved lignin. This technique is based on a flow analysis system with a Nafion membrane interface. The AQ passed through the membrane is converted into its reduced form, AHQ, using sodium hydrosulfite. AHQ has distinguished absorption characteristics in the...

Thermal and spectroscopic studies on solid ibuprofen complexes of lighter trivalent lanthanides

Energy Technology Data Exchange (ETDEWEB)

Gálico, D.A.; Holanda, B.B.C.; Guerra, R.B.; Legendre, A.O.; Rinaldo, D. [UNESP – Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260 (Brazil); Treu-Filho, O. [UNESP – Univ Estadual Paulista, Instituto de Química, São Paulo CEP 14800-900 (Brazil); Bannach, G., E-mail: gilbert@fc.unesp.br [UNESP – Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260 (Brazil)

2014-01-10

Highlights: • Lighter trivalent lanthanide complexes of ibuprofen have been synthesized. • The TG-FTIR allowed the identification of propane as the gas evolved during the thermal decomposition of the neodymium compound. • The thermal analysis provided information about the composition, dehydration, thermal behavior and thermal decomposition of the samples. • The theoretical and experimental spectroscopic studies suggest that the carboxylate group of ibuprofen is coordinated to the metals by a bidentate bond. - Abstract: Solid-state compounds of general formula Ln(L){sub 3}, in which L is ibuprofen and Ln stands for trivalent La, Ce, Pr, Nd, Sm and Eu, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), X-ray powder diffractometry (DRX), complexometry, Fourier-transformed infrared spectroscopy (FTIR) and thermogravimetry coupled to Fourier-transformed infrared spectroscopy (TG-FTIR) were used to characterize these compounds. The results provided information concerning the chemical composition, dehydration, coordination modes of the ligands, crystallinity of the samples, thermal behavior and thermal decomposition of the compounds. The theoretical and experimental spectroscopic studies suggest that ibuprofen coordinates through the carboxylate group as a chelating ligand.

Thermal and spectroscopic studies on solid ibuprofen complexes of lighter trivalent lanthanides

International Nuclear Information System (INIS)

Gálico, D.A.; Holanda, B.B.C.; Guerra, R.B.; Legendre, A.O.; Rinaldo, D.; Treu-Filho, O.; Bannach, G.

2014-01-01

Highlights: • Lighter trivalent lanthanide complexes of ibuprofen have been synthesized. • The TG-FTIR allowed the identification of propane as the gas evolved during the thermal decomposition of the neodymium compound. • The thermal analysis provided information about the composition, dehydration, thermal behavior and thermal decomposition of the samples. • The theoretical and experimental spectroscopic studies suggest that the carboxylate group of ibuprofen is coordinated to the metals by a bidentate bond. - Abstract: Solid-state compounds of general formula Ln(L) 3 , in which L is ibuprofen and Ln stands for trivalent La, Ce, Pr, Nd, Sm and Eu, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), X-ray powder diffractometry (DRX), complexometry, Fourier-transformed infrared spectroscopy (FTIR) and thermogravimetry coupled to Fourier-transformed infrared spectroscopy (TG-FTIR) were used to characterize these compounds. The results provided information concerning the chemical composition, dehydration, coordination modes of the ligands, crystallinity of the samples, thermal behavior and thermal decomposition of the compounds. The theoretical and experimental spectroscopic studies suggest that ibuprofen coordinates through the carboxylate group as a chelating ligand

Spectroscopic Observations and Analysis of the Unusual Type Ia SN1999ac

International Nuclear Information System (INIS)

Garavini, G.; Aldering, G.; Amadon, A.; Amanullah, R.; Astier, P.; Balland, C.; Blanc, G.; Conley, A.; Dahlen, T.; Deustua, S.E.; Ellis, R.; Fabbro, S.; Fadeyev, V.; Fan, X.; Folatelli, G.; Frye, B.; Gates, E.L.; Gibbons, R.; Goldhaber, G.; Goldman, B.; Goobar, A.; Groom, D.E.; Haissinski, J.; Hardin, D.; Hook, I.; Howell, D.A.; Kent, S.; Kim, A.G.; Knop, R.A.; Kowalski, M.; Kuznetsova, N.; Lee, B.C.; Lidman, C.; Mendez, J.; Miller, G.J.; Moniez, M.; Mouchet, M.; Mourao, A.; Newberg, H.; Nobili, S.; Nugent, P.E.; Pain, R.; Perdereau, O.; Perlmutter, S.; Quimby, R.; Regnault, N.; Rich, J.; Richards, G.T.; Ruiz-Lapuente, P.; Schaefer, B.E.; Schahmaneche, K.; Smith, E.; Spadafora, A.L.; Stanishev, V.; Thomas, R.C.; Walton, N.A.; Wang, L.; Wood-Vasey, W.M.

2005-01-01

The authors present optical spectra of the peculiar Type Ia supernova (SN Ia) 1999ac. The data extend from -15 to +42 days with respect to B-band maximum and reveal an event that is unusual in several respects. prior to B-band maximum, the spectra resemble those of SN 1999aa, a slowly declining event, but possess stronger Si II and Ca II signatures (more characteristic of a spectroscopically normal SN). Spectra after B-band maximum appear more normal. The expansion velocities inferred from the Iron lines appear to be lower than average; whereas, the expansion velocity inferred from Calcium H and K are higher than average. The expansion velocities inferred from the Iron lines appear to be lower than average; whereas, the expansion velocity inferred from Calcium H and K are higher than average. The expansion velocities inferred from Si II are among the slowest ever observed, though SN 1999ac is not particularly dim. The analysis of the parameters v 10 (Si II), R(Si II), v, and Δm 15 further underlines the unique characteristics of SN 1999ac. They find convincing evidence of C II λ6580 in the day -15 spectrum with ejection velocity v > 16,000 km s -1 , but this signature disappears by day -9. This rapid evolution at early times highlights the importance of extremely early-time spectroscopy

Ultrafast Spectroscopic Noninvasive Probe of Vertical Carrier Transport in Heterostructure Devices

Science.gov (United States)

2016-03-01

ARL-TR-7618 ● MAR 2016 US Army Research Laboratory Ultrafast Spectroscopic Noninvasive Probe of Vertical Carrier Transport in...US Army Research Laboratory Ultrafast Spectroscopic Noninvasive Probe of Vertical Carrier Transport in Heterostructure Devices by Blair C...Spectroscopic Noninvasive Probe of Vertical Carrier Transport in Heterostructure Devices 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT

Development and analysis of spectroscopic learning tools and the light and spectroscopy concept inventory for introductory college astronomy

Science.gov (United States)

Bardar, Erin M.

Electromagnetic radiation is the fundamental carrier of astronomical information. Spectral features serve as the fingerprints of the universe, revealing many important properties of objects in the cosmos such as temperature, elemental compositions, and relative motion. Because of its importance to astronomical research, the nature of light and the electromagnetic spectrum is by far the most universally covered topic in astronomy education. Yet, to the surprise and disappointment of instructors, many students struggle to understand underlying fundamental concepts related to light and spectroscopic phenomena. This dissertation describes research into introductory college astronomy students' understanding of light and spectroscopy concepts, through the development and analysis of both instructional materials and an assessment instrument. The purpose of this research was two-fold: (1) to develop a novel suite of spectroscopic learning tools that enhance student understanding of light and spectroscopy and (2) to design and validate a Light and Spectroscopy Concept Inventory (LSCI) with the sensitivity to distinguish the relative effectiveness of various teaching interventions within the context of introductory college astronomy. Through a systematic investigation that included multiple rounds of clinical interviews, open-ended written surveys, and multiple-choice testing, introductory college astronomy students' commonly held misconceptions and reasoning difficulties were explored for concepts relating to: (1) The nature of the electromagnetic spectrum, including the interrelationships of wavelength, frequency, energy, and speed; (2) interpretation of Doppler shift; (3) properties of blackbody radiation; and (4) the connection between spectral features and underlying physical processes. These difficulties guided the development of instructional materials including six unique "homelab" exercises, a binocular spectrometer, a spectral analysis software tool, and the 26

Spectroscopic ellipsometry and polarimetry for materials and systems analysis at the nanometer scale: state-of-the-art, potential, and perspectives

Science.gov (United States)

Bergmair, Michael; Bruno, Giovanni; Cattelan, Denis; Cobet, Christoph; de Martino, Antonello; Fleischer, Karsten; Dohcevic-Mitrovic, Zorana; Esser, Norbert; Galliet, Melanie; Gajic, Rados; Hemzal, Dušan; Hingerl, Kurt; Humlicek, Josef; Ossikovski, Razvigor; Popovic, Zoran V.; Saxl, Ottilia

2009-01-01

This paper discusses the fundamentals, applications, potential, limitations, and future perspectives of polarized light reflection techniques for the characterization of materials and related systems and devices at the nanoscale. These techniques include spectroscopic ellipsometry, polarimetry, and reflectance anisotropy. We give an overview of the various ellipsometry strategies for the measurement and analysis of nanometric films, metal nanoparticles and nanowires, semiconductor nanocrystals, and submicron periodic structures. We show that ellipsometry is capable of more than the determination of thickness and optical properties, and it can be exploited to gain information about process control, geometry factors, anisotropy, defects, and quantum confinement effects of nanostructures. PMID:21170135

PG 1605+072 in Wet XCov22: Support for the Multi Site Spectroscopic Telescope

Directory of Open Access Journals (Sweden)

Schuh S. L.

2003-03-01

Full Text Available The Multi-site spectroscopic telescope is a virtual instrument and the name of a collaboration that opens up a new observational window by combining continuous observations of spectroscopic variations and simultaneous photometric monitoring. This constitutes an enormous observational effort, but in return promises to finally provide access to a mode identification for and an asteroseismological analysis of the pulsating sdB star PG 1605+072. Multi-Site Spectroscopic Telescope observations for this object have been secured during a large coordinated campaign in May and June of the year 2002. The frequency resolution and coverage of the photometric time series has been noticeably enhanced by a significant contribution from the Whole Earth Telescope, which was used to observe PG 1605+072 as an alternate target during the WET XCov22 campaign, also conducted in May 2002. This paper briefly outlines the motivation for the MSST project and tries to give a first assessment of the overall quality of the data obtained, with a focus on the Whole Earth Telescope observations.

Optical spectroscopic analysis for the discrimination of extra-virgin olive-oil (Conference Presentation)

Science.gov (United States)

McReynolds, Naomi; Auñón Garcia, Juan M.; Guengerich, Zoe; Smith, Terry K.; Dholakia, Kishan

2017-02-01

We present an optical spectroscopic technique, making use of both Raman signals and fluorescence spectroscopy, for the identification of five brands of commercially available extra-virgin olive-oil (EVOO). We demonstrate our technique on both a `bulk-optics' free-space system and a compact device. Using the compact device, which is capable of recording both Raman and fluorescence signals, we achieved an average sensitivity and specificity of 98.4% and 99.6% for discrimination, respectively. Our approach demonstrates that both Raman and fluorescence spectroscopy can be used for portable discrimination of EVOOs which obviates the need to use centralised laboratories and opens up the prospect of in-field testing. This technique may enable detection of EVOO that has undergone counterfeiting or adulteration. One of the main challenges facing Raman spectroscopy for use in quality control of EVOOs is that the oxidation of EVOO, which naturally occurs due to aging, causes shifts in Raman spectra with time, which implies regular retraining would be necessary. We present a potential method of analysis to minimize the effect that aging has on discrimination efficiency; we show that by discarding the first principal component, which contains information on the variations due to oxidation, we can improve discrimination efficiency thus improving the robustness of our technique.

Constraining reconnection region conditions using imaging and spectroscopic analysis of a coronal jet

Science.gov (United States)

Brannon, Sean; Kankelborg, Charles

2017-08-01

Coronal jets typically appear as thin, collimated structures in EUV and X-ray wavelengths, and are understood to be initiated by magnetic reconnection in the lower corona or upper chromosphere. Plasma that is heated and accelerated upward into coronal jets may therefore carry indirect information on conditions in the reconnection region and current sheet located at the jet base. On 2017 October 14, the Interface Region Imaging Spectrograph (IRIS) and Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO/AIA) observed a series of jet eruptions originating from NOAA AR 12599. The jet structure has a length-to-width ratio that exceeds 50, and remains remarkably straight throughout its evolution. Several times during the observation bright blobs of plasma are seen to erupt upward, ascending and subsequently descending along the structure. These blobs are cotemporal with footpoint and arcade brightenings, which we believe indicates multiple episodes of reconnection at the structure base. Through imaging and spectroscopic analysis of jet and footpoint plasma we determine a number of properties, including the line-of-sight inclination, the temperature and density structure, and lift-off velocities and accelerations of jet eruptions. We use these properties to constrain the geometry of the jet structure and conditions in reconnection region.

Specific binding of a dihydropyrimidinone derivative with DNA: Spectroscopic, calorimetric and modeling investigations

International Nuclear Information System (INIS)

Wang Gongke; Yan Changling; Wang Dongchao; Li Dan; Lu Yan

2012-01-01

One of the dihydropyrimidinone derivative 5-(ethoxycarbonyl)-6-methyl-4-(4-methoxyphenyl) -3,4-dihydropyrimidin-2(1H)-one (EMMD) was synthesized, and its binding properties with calf-thymus DNA (ctDNA) were investigated using spectroscopic, viscometric, isothermal titration calorimetric (ITC) and molecular modeling techniques. Fluorescence spectra suggested that the fluorescence enhancement of the binding interaction of EMMD to ctDNA was a static process with ground state complex formation. The binding constant determined with spectroscopic titration and ITC was found to be in the same order of 10 4 M −1 . According to the results of the viscosity analysis, fluorescence competitive binding experiment, fluorescence quenching studies, absorption spectral and ITC investigations, it can be concluded that EMMD is intercalative binding to ctDNA. Furthermore, the results of molecular modeling confirmed those obtained from spectroscopic, viscosimetric and ITC investigations. Additionally, ITC studies also indicated that the binding interaction is predominantly enthalpy driven. - Highlights: ► Medically important dihydropyrimidinones derivative EMMD is synthesized. ► EMMD is intercalative binding into ctDNA helix. ► Hydrogen bonding may play an essential role in the binding of EMCD with ctDNA. ► This binding interaction is predominantly enthalpy driven.

Constraints on early-type galaxy structure from spectroscopically selected gravitational lenses

Science.gov (United States)

Bolton, Adam Stallard

2005-11-01

This thesis describes all aspects of a unique spectroscopic survey for strong galaxy-galaxy gravitational lenses: motivation, candidate selection, ground- based spectroscopic follow-up, Hubble Space Telescope imaging, data analysis, and results on the radial density profile of the lens galaxies. The lens candidates are selected from within the spectroscopic database of the Sloan Digital Sky Survey (SDSS) based on the appearance of two significantly different redshifts along the same line of sight, and lenses are confirmed within the candidate sample by follow-up imaging and spectroscopy. The sample of [approximate]20 early-type lenses presented in this thesis represents the largest single strong-lens galaxy sample discovered and published to date. These lenses probe the mass of the lens galaxies on scales roughly equal to one-half effective radius. We find a dynamical normalization between isothermal lens-model velocity dispersions and aperture-corrected SDSS stellar velocity dispersions of f = s lens /s stars = 0.95 +/- 0.03. By combining lens-model Einstein radii and de Vaucouleurs effective radii with stellar velocity dispersions through the Jeans equation, we find that the logarithmic slope [Special characters omitted.] of the density profile in our lens galaxies (r 0 ( [Special characters omitted.] ) is on average slightly steeper than isothermal ([Special characters omitted.] = 2) with a modest intrinsic scatter. Parameterizing the intrinsic distribution in [Special characters omitted.] as Gaussian, we find a maximum-likelihood mean of [Special characters omitted. ] and standard deviation of s[Special characters omitted.] = [Special characters omitted.] (68% confidence, for isotropic velocity-dispersion models). Our results rule out a single universal logarithmic density slope at >99.995% confidence. The success of this spectroscopic lens survey suggests that similar projects should be considered as an explicit science goal of future redshift surveys. (Copies

Spectroscopic and imaging diagnostics of pulsed laser deposition laser plasmas

International Nuclear Information System (INIS)

Thareja, Raj K.

2002-01-01

An overview of laser spectroscopic techniques used in the diagnostics of laser ablated plumes used for thin film deposition is given. An emerging laser spectroscopic imaging technique for the laser ablation material processing is discussed. (author)

Ethyl 2,6-Dimethoxybenzoate: Synthesis, Spectroscopic and X-ray Crystallographic Analysis

Directory of Open Access Journals (Sweden)

Jonathan M. White

2012-05-01

Full Text Available The acid catalyzed esterification of 2,6-dimethoxybenzoic acid (1 in the presence of absolute ethanol afforded ethyl 2, 6-dimethoxybenzoate (2. The structure of the resulting compound was supported by spectroscopic data and unambiguously confirmed by single crystal X-ray diffraction studies. The title compound crystallized in the triclinic space group P ī with unit cell parameters a = 8.5518(3 Å, b = 10.8826(8 Å, c = 11.9939(6 Å, α = 101.273(5°, β = 98.287(3°, γ = 94.092(4°, V = 1077.54(10 Å3, Z = 4, Dc = 1.296 Mg/m3, F(000 = 448 and μ = 0.098 mm−1. Compound (2 crystallizes with two molecules in the asymmetric unit with similar conformations.

High throughput assessment of cells and tissues: Bayesian classification of spectral metrics from infrared vibrational spectroscopic imaging data.

Science.gov (United States)

Bhargava, Rohit; Fernandez, Daniel C; Hewitt, Stephen M; Levin, Ira W

2006-07-01

Vibrational spectroscopy allows a visualization of tissue constituents based on intrinsic chemical composition and provides a potential route to obtaining diagnostic markers of diseases. Characterizations utilizing infrared vibrational spectroscopy, in particular, are conventionally low throughput in data acquisition, generally lacking in spatial resolution with the resulting data requiring intensive numerical computations to extract information. These factors impair the ability of infrared spectroscopic measurements to represent accurately the spatial heterogeneity in tissue, to incorporate robustly the diversity introduced by patient cohorts or preparative artifacts and to validate developed protocols in large population studies. In this manuscript, we demonstrate a combination of Fourier transform infrared (FTIR) spectroscopic imaging, tissue microarrays (TMAs) and fast numerical analysis as a paradigm for the rapid analysis, development and validation of high throughput spectroscopic characterization protocols. We provide an extended description of the data treatment algorithm and a discussion of various factors that may influence decision-making using this approach. Finally, a number of prostate tissue biopsies, arranged in an array modality, are employed to examine the efficacy of this approach in histologic recognition of epithelial cell polarization in patients displaying a variety of normal, malignant and hyperplastic conditions. An index of epithelial cell polarization, derived from a combined spectral and morphological analysis, is determined to be a potentially useful diagnostic marker.

Obtaining the Electron Angular Momentum Coupling Spectroscopic Terms, jj

Science.gov (United States)

Orofino, Hugo; Faria, Roberto B.

2010-01-01

A systematic procedure is developed to obtain the electron angular momentum coupling (jj) spectroscopic terms, which is based on building microstates in which each individual electron is placed in a different m[subscript j] "orbital". This approach is similar to that used to obtain the spectroscopic terms under the Russell-Saunders (LS) coupling…

Modeling of a Low-Background Spectroscopic Position-Sensitive Neutron Detector

Energy Technology Data Exchange (ETDEWEB)

Postovarova, Daria; Evsenin, Alexey; Gorshkov, Igor; Kuznetsov, Andrey; Osetrov, Oleg; Vakhtin, Dmitry; Yurmanov, Pavel [V.G. Khlopin Radium Institute, 194021, 28, 2nd Murinsky pr., Saint-Petersburg (Russian Federation)

2011-12-13

A new low-background spectroscopic direction-sensitive neutron detector that would allow one to reduce the neutron background component in passive and active neutron detection techniques is proposed. The detector is based on thermal neutron detectors surrounded by a fast neutron scintillation detector, which serves at the same time as a neutron moderator. Direction sensitivity is achieved by coincidence/anticoincidence analysis between different parts of the scintillator. Results of mathematical modeling of several detector configurations are presented.

Modeling of a Low-Background Spectroscopic Position-Sensitive Neutron Detector

International Nuclear Information System (INIS)

Postovarova, Daria; Evsenin, Alexey; Gorshkov, Igor; Kuznetsov, Andrey; Osetrov, Oleg; Vakhtin, Dmitry; Yurmanov, Pavel

2011-01-01

A new low-background spectroscopic direction-sensitive neutron detector that would allow one to reduce the neutron background component in passive and active neutron detection techniques is proposed. The detector is based on thermal neutron detectors surrounded by a fast neutron scintillation detector, which serves at the same time as a neutron moderator. Direction sensitivity is achieved by coincidence/anticoincidence analysis between different parts of the scintillator. Results of mathematical modeling of several detector configurations are presented.

Proton magnetic resonance spectroscopic imaging in neurodegenerative diseases

International Nuclear Information System (INIS)

Schuff, Norbert; Vermathen, Peter; Maudsley, Andrew A.; Weiner, Michael W.

1999-01-01

Proton magnetic resonance spectroscopic imaging ( 1 H MRSI) was used to investigate changes in brain metabolites in Alzheimer's disease, epilepsy, and amyotrophic lateral sclerosis. Examples of results from several ongoing clinical studies are provided. Multislice 1 H MRSI of the human brain, without volume pre selection offers considerable advantage over previously available techniques. Furthermore, MRI tissue segmentation and completely automated spectral curve fitting greatly facilitate quantitative data analysis. Future efforts will be devoted to obtain full volumetric brain coverage and data acquisition at short spin-echo times (TE<30 ms) for the detection of metabolites. (author)

TOWARD A SPECTROSCOPIC CENSUS OF WHITE DWARFS WITHIN 40 pc OF THE SUN

International Nuclear Information System (INIS)

Limoges, M.-M.; Bergeron, P.; Lépine, S.

2013-01-01

We present the preliminary results of a survey aimed at significantly increasing the range and completeness of the local census of spectroscopically confirmed white dwarfs. The current census of nearby white dwarfs is reasonably complete only to about 20 pc of the Sun, a volume that includes around 130 white dwarfs, a sample too small for detailed statistical analyses. This census is largely based on follow-up investigations of stars with very large proper motions. We describe here the basis of a method that will lead to a catalog of white dwarfs within 40 pc of the Sun and north of the celestial equator, thus increasing by a factor of eight the extent of the northern sky census. White dwarf candidates are identified from the SUPERBLINK proper motion database, allowing us to investigate stars down to a proper motion limit μ > 40 mas yr –1 , while minimizing the kinematic bias for nearby objects. The selection criteria and distance estimates are based on a combination of color-magnitude and reduced proper motion diagrams. Our follow-up spectroscopic observation campaign has so far uncovered 193 new white dwarfs, among which we identify 127 DA (including 9 DA+dM and 4 magnetic), 1 DB, 56 DC, 3 DQ, and 6 DZ stars. We perform a spectroscopic analysis on a subsample of 84 DAs, and provide their atmospheric parameters. In particular, we identify 11 new white dwarfs with spectroscopic distances within 25 pc of the Sun, including five candidates to the D < 20 pc subset.

Iterative estimation of the background in noisy spectroscopic data

International Nuclear Information System (INIS)

Zhu, M.H.; Liu, L.G.; Cheng, Y.S.; Dong, T.K.; You, Z.; Xu, A.A.

2009-01-01

In this paper, we present an iterative filtering method to estimate the background of noisy spectroscopic data. The proposed method avoids the calculation of the average full width at half maximum (FWHM) of the whole spectrum and the peak regions, and it can estimate the background efficiently, especially for spectroscopic data with the Compton continuum.

Spectroscopic databases - A tool for structure elucidation

Energy Technology Data Exchange (ETDEWEB)

Luksch, P [Fachinformationszentrum Karlsruhe, Gesellschaft fuer Wissenschaftlich-Technische Information mbH, Eggenstein-Leopoldshafen (Germany)

1990-05-01

Spectroscopic databases have developed to useful tools in the process of structure elucidation. Besides the conventional library searches, new intelligent programs have been added, that are able to predict structural features from measured spectra or to simulate for a given structure. The example of the C13NMR/IR database developed at BASF and available on STN is used to illustrate the present capabilities of online database. New developments in the field of spectrum simulation and methods for the prediction of complete structures from spectroscopic information are reviewed. (author). 10 refs, 5 figs.

Atomic emission spectroscopic investigations for determining depth profiles at boride layers on iron materials

International Nuclear Information System (INIS)

Danzer, K.; Marx, G.

1980-01-01

A combination of atomic emission spectroscopic surface analysis and mechanical removement of defined surface areas in layers by grinding yields information about the depth distribution of boron in iron. In addition, the evaluation with the aid of the two-dimensional variance analysis leads to statements on the homogeneous distribution within individual layers at different depth. The results obtained in this way are in agreement with those of other methods

Clays as green catalysts in the cholesterol esterification: spectroscopic characterization and polymorphs identification by thermal analysis methods. An interdisciplinary laboratorial proposal for the undergraduate level

International Nuclear Information System (INIS)

Maria, Teresa M R.; Nunes, Rui M. D.; Pereira, Mariette M.; Eusebio, M. Ermelinda S.

2009-01-01

A laboratory experiment that enables the professor to introduce the problematic of sustainable development in pharmaceutical chemistry to undergraduate students is proposed, using a simple synthetic procedure. Cholesteryl acetate is prepared by the esterification of cholesterol using Montmorillonite K10 as heterogeneous catalyst. Cholesterol and cholesteryl acetate are characterized by spectroscopic ( 1 H RMN, 13 C RMN, FTIR) and thermal analysis techniques. The thermal methods are used to introduce the concepts of polymorphism and the nature of mesophases. (author)

Spectroscopic amplifier for pin diode

International Nuclear Information System (INIS)

Alonso M, M. S.; Hernandez D, V. M.; Vega C, H. R.

2014-10-01

The photodiode remains the basic choice for the photo-detection and is widely used in optical communications, medical diagnostics and field of corpuscular radiation. In detecting radiation it has been used for monitoring radon and its progeny and inexpensive spectrometric systems. The development of a spectroscopic amplifier for Pin diode is presented which has the following characteristics: canceler Pole-Zero (P/Z) with a time constant of 8 μs; constant gain of 57, suitable for the acquisition system; 4th integrator Gaussian order to waveform change of exponential input to semi-Gaussian output and finally a stage of baseline restorer which prevents Dc signal contribution to the next stage. The operational amplifier used is the TLE2074 of BiFET technology of Texas Instruments with 10 MHz bandwidth, 25 V/μs of slew rate and a noise floor of 17 nv/(Hz)1/2. The integrated circuit has 4 operational amplifiers and in is contained the total of spectroscopic amplifier that is the goal of electronic design. The results show like the exponential input signal is converted to semi-Gaussian, modifying only the amplitude according to the specifications in the design. The total system is formed by the detector, which is the Pin diode, a sensitive preamplifier to the load, the spectroscopic amplifier that is what is presented and finally a pulse height analyzer (Mca) which is where the spectrum is shown. (Author)

Spectroscopic detection of fluorescent protein marker gene activity in genetically modified plants

Science.gov (United States)

Liew, O. W.; Chong, Jenny P. C.; Asundi, Anand K.

2005-04-01

This work focuses on developing a portable fibre optic fluorescence analyser for rapid identification of genetically modified plants tagged with a fluorescent marker gene. Independent transgenic tobacco plant lines expressing the enhanced green fluorescence protein (EGFP) gene were regenerated following Agrobacterium-mediated gene transfer. Molecular characterisation of these plant lines was carried out at the DNA level by PCR screening to confirm their transgenic status. Conventional transgene expression analysis was then carried out at the RNA level by RT-PCR and at the protein level by Western blotting using anti-GFP rabbit antiserum. The amount of plant-expressed EGFP on a Western blot was quantified against known amounts of purified EGFP by scanning densitometry. The expression level of EGFP in transformed plants was found to range from 0.1 - 0.6% of total extractable protein. A comparison between conventional western analysis of transformants and direct spectroscopic quantification using the fibre optic fluorescence analyser was made. The results showed that spectroscopic measurements of fluorescence emission from strong EGFP expressors correlated positively with Western blot data. However, the fluorescence analyser was also able to identify weakly expressing plant transformants below the detection limit of colorimetric Western blotting.

Spectroscopic study of honey from Apis mellifera from different regions in Mexico

Science.gov (United States)

Frausto-Reyes, C.; Casillas-Peñuelas, R.; Quintanar-Stephano, JL; Macías-López, E.; Bujdud-Pérez, JM; Medina-Ramírez, I.

2017-05-01

The objective of this study was to analyze by Raman and UV-Vis-NIR Spectroscopic techniques, Mexican honey from Apis Mellífera, using representative samples with different botanic origins (unifloral and multifloral) and diverse climates. Using Raman spectroscopy together with principal components analysis, the results obtained represent the possibility to use them for determination of floral origin of honey, independently of the region of sampling. For this, the effect of heat up the honey was analyzed in relation that it was possible to greatly reduce the fluorescence background in Raman spectra, which allowed the visualization of fructose and glucose peaks. Using UV-Vis-NIR, spectroscopy, a characteristic spectrum profile of transmittance was obtained for each honey type. In addition, to have an objective characterization of color, a CIE Yxy and CIE L*a*b* colorimetric register was realized for each honey type. Applying the principal component analysis and their correlation with chromaticity coordinates allowed classifying the honey samples in one plot as: cutoff wavelength, maximum transmittance, tones and lightness. The results show that it is possible to obtain a spectroscopic record of honeys with specific characteristics by reducing the effects of fluorescence.

First line shape analysis and spectroscopic parameters for the ν11 band of 12C2H4

KAUST Repository

Es-sebbar, Et-touhami

2016-08-11

An accurate knowledge of line intensities, collisional broadening coefficients and narrowing parameters is necessary for the interpretation of high-resolution infrared spectra of the Earth and other planetary atmospheres. One of the most promising spectral domains for (C2H4)-C-12 monitoring in such environments is located near the 336 gm window, through its v(11) C-H stretching mode. In this paper, we report an extensive study in which we precisely determine spectroscopic parameters of (C2H4)-C-12 v(11) band at 297 +/- 1 K, using a narrow Difference-Frequency-Generation (DFG) laser with 10(-4) cm(-1) resolution. Absorption measurements were performed in the 2975-2980 cm(-1) spectral window to investigate 32 lines corresponding to where, J\\'ka\\',kc\\'<- Jka,kc, 5 <= J <= 7; 0.5 <= K-a <= 6 and 1 <= K-c <= 14. Spectroscopic parameters are retrieved using either Voigt or appropriate Galatry profile to simulate the measured (C2H4)-C-12 line shape. Line intensities along with self-broadening coefficients are reported for all lines. Narrowing coefficients for each isolated line are also derived. To our knowledge, the current study reports the first extensive spectroscopic parameter measurements of the (C2H4)-C-12 v(11) band in the 2975-2980 cm(-1) range. (C) 2016 Elsevier Ltd. All rights reserved.

First line shape analysis and spectroscopic parameters for the ν11 band of 12C2H4

KAUST Repository

Es-sebbar, Et-touhami; Mantzaras, John; Benilan, Yves; Farooq, Aamir

2016-01-01

An accurate knowledge of line intensities, collisional broadening coefficients and narrowing parameters is necessary for the interpretation of high-resolution infrared spectra of the Earth and other planetary atmospheres. One of the most promising spectral domains for (C2H4)-C-12 monitoring in such environments is located near the 336 gm window, through its v(11) C-H stretching mode. In this paper, we report an extensive study in which we precisely determine spectroscopic parameters of (C2H4)-C-12 v(11) band at 297 +/- 1 K, using a narrow Difference-Frequency-Generation (DFG) laser with 10(-4) cm(-1) resolution. Absorption measurements were performed in the 2975-2980 cm(-1) spectral window to investigate 32 lines corresponding to where, J'ka',kc'<- Jka,kc, 5 <= J <= 7; 0.5 <= K-a <= 6 and 1 <= K-c <= 14. Spectroscopic parameters are retrieved using either Voigt or appropriate Galatry profile to simulate the measured (C2H4)-C-12 line shape. Line intensities along with self-broadening coefficients are reported for all lines. Narrowing coefficients for each isolated line are also derived. To our knowledge, the current study reports the first extensive spectroscopic parameter measurements of the (C2H4)-C-12 v(11) band in the 2975-2980 cm(-1) range. (C) 2016 Elsevier Ltd. All rights reserved.

ON THE SPECTROSCOPIC CLASSES OF NOVAE IN M33

International Nuclear Information System (INIS)

Shafter, A. W.; Darnley, M. J.; Bode, M. F.; Ciardullo, R.

2012-01-01

We report the initial results from an ongoing multi-year spectroscopic survey of novae in M33. The survey resulted in the spectroscopic classification of six novae (M33N 2006-09a, 2007-09a, 2009-01a, 2010-10a, 2010-11a, and 2011-12a) and a determination of rates of decline (t 2 times) for four of them (2006-09a, 2007-09a, 2009-01a, and 2010-10a). When these data are combined with existing spectroscopic data for two additional M33 novae (2003-09a and 2008-02a), we find that five of the eight novae with available spectroscopic class appear to be members of either the He/N or Fe IIb (hybrid) classes, with only two clear members of the Fe II spectroscopic class. This initial finding is very different from what would be expected based on the results for M31 and the Galaxy where Fe II novae dominate, and the He/N and Fe IIb classes together make up only ∼20% of the total. It is plausible that the increased fraction of He/N and Fe IIb novae observed in M33 thus far may be the result of the younger stellar population that dominates this galaxy, which is expected to produce novae that harbor generally more massive white dwarfs than those typically associated with novae in M31 or the Milky Way.

Spectroscopic studies of the transplutonium elements

International Nuclear Information System (INIS)

Carnall, W.T.; Conway, J.G.

1983-01-01

The challenging opportunity to develop insights into both atomic structure and the effects of bonding in compounds makes the study of actinide spectroscopy a particularly fruitful and exciting area of scientific endeavor. It is also the interpretation of f-element spectra that has stimulated the development of the most sophisticated theoretical modeling attempted for any elements in the periodic table. The unique nature of the spectra and the wealth of fine detail revealed make possible sensitive tests of both physical models and the results of Hartree-Fock type ab initio calculations. This paper focuses on the unique character of heavy actinide spectroscopy. It discusses how it differs from that of the lighter member of the series and what are the special properties that are manifested. Following the introduction, the paper covers the following: (1) the role of systematic studies and the relationships of heavy-actinide spectroscopy to ongoing spectroscopic investigations of the lighter members of the series; (2) atomic (free-ion) spectra which covers the present status of spectroscopic studies with transplutonium elements, and future needs and directions in atomic spectroscopy; (3) the spectra of actinide compounds which covers the present status and future directions of spectroscopic studies with compounds of the transplutonium elements; and other spectroscopies. 1 figure, 2 tables

Raman spectroscopic analysis identifies testicular microlithiasis as intratubular hydroxyapatite.

Science.gov (United States)

De Jong, B W D; De Gouveia Brazao, C A; Stoop, H; Wolffenbuttel, K P; Oosterhuis, J W; Puppels, G J; Weber, R F A; Looijenga, L H J; Kok, D J

2004-01-01

As diagnosed by ultrasonography, testicular microlithiasis is associated with various benign and malignant conditions. The molecular constitution of these microliths is largely unknown. Raman spectroscopy provides detailed in situ information about the molecular composition of tissues and to our knowledge it has not been applied to gonadal microliths. We analyzed the molecular composition of gonadal microlithiasis and its surrounding region using Raman spectroscopy in malignant and benign conditions. Multiple microliths from 6 independent samples diagnosed with gonadal microlithiasis by ultrasound and histologically confirmed were investigated by Raman spectroscopy. The samples included 4 testicular parenchyma samples adjacent to a germ cell tumor (4 seminomas), a gonadoblastoma of a dysgenetic gonad and testicular biopsy of a subfertile male without malignancy. Raman spectroscopic mapping demonstrated that testicular microliths were located within the seminiferous tubule. Glycogen surrounded all microliths in the samples associated with germ cell neoplasm but not in the benign case. The molecular composition of the 26 microliths in all 6 conditions was pure hydroxyapatite. Microliths in the testis are located in the seminiferous tubules and composed of hydroxyapatite. In cases of germ cell neoplasm they co-localize with glycogen deposits.

SPECTROSCOPIC ANALYSIS OF FIVE PHYLOGENETICALLY DISTANT FUNGI (DIVISION: ASCOMYCETE FROM VELLAR ESTUARY, SOUTHEAST COAST OF INDIA – A PILOT STUDY

Directory of Open Access Journals (Sweden)

Jayachandran Subburaj

2013-04-01

Full Text Available Fungal taxonomy is dynamically driven towards controversial discipline that consequently requires changes in nomenclature. Scarcity of microbiological expertise particularly for marine fungi is another major setback for these taxonomical differences. Here, five different species pharmacologically important marine fungi under Division Ascomycete were studied for their spectral variation. This work verified the practical applicability of FT-IR microspectroscopy technique for early and rapid identification of these species based on the spectral data showed striking difference with their major biomolecules such as lipids, proteins and nucleic acids produced by them. Spectra of all the species showed striking differences while individual peaks of each spectrum are parallel to each other in their respective spectral regions. Aspergillus oryzae have intense peaks in the lipid and nucleic acid spectral region and moderate bands in the amide spectrum. Phoma herbarum and Trichoderma piluliferum showed intense peaks in the protein spectral region but moderate peaks in the lipid and nucleic acid regions. Hypocrea lixii and Meyerozyma guilliermandii have less intense peaks in all the five spectral regions. This unique spectral representation is concordant with the cluster analysis dendrogram by minimum variance statistical method where low spectroscopic distance was found between H. lixii and M. guilliermondii whereas a higher spectroscopic distance was found between P. herbarum and T. piluliferum. FTIR spectroscopy delivers a combined advantage for efficient fungal classification as well as simultaneous visualization of chemical composition of samples as evident from this study.

Spectroscopic studies of hydrogen atom and molecule collisions: Performance report

International Nuclear Information System (INIS)

Kielkopf, J.

1986-01-01

This research is concerned with spectroscopic measurements of collisions in atomic and molecular hydrogen in order to clarify the basic physical processes that take place during radiative collisions and to provide experimental values for systems where the theoretical analysis is tractable. To this end, we proposed to measure from the cores to the far wings the profiles of the spectral lines of atomic hydrogen broadened by molecular hydrogen and noble gases, and to study energy transfer in the atom and molecule

Recent advances in the applications of vibrational spectroscopic imaging and mapping to pharmaceutical formulations

Science.gov (United States)

Ewing, Andrew V.; Kazarian, Sergei G.

2018-05-01

Vibrational spectroscopic imaging and mapping approaches have continued in their development and applications for the analysis of pharmaceutical formulations. Obtaining spatially resolved chemical information about the distribution of different components within pharmaceutical formulations is integral for improving the understanding and quality of final drug products. This review aims to summarise some key advances of these technologies over recent years, primarily since 2010. An overview of FTIR, NIR, terahertz spectroscopic imaging and Raman mapping will be presented to give a perspective of the current state-of-the-art of these techniques for studying pharmaceutical samples. This will include their application to reveal spatial information of components that reveals molecular insight of polymorphic or structural changes, behaviour of formulations during dissolution experiments, uniformity of materials and detection of counterfeit products. Furthermore, new advancements will be presented that demonstrate the continuing novel applications of spectroscopic imaging and mapping, namely in FTIR spectroscopy, for studies of microfluidic devices. Whilst much of the recently developed work has been reported by academic groups, examples of the potential impacts of utilising these imaging and mapping technologies to support industrial applications have also been reviewed.

Determination of mercury and copper in water samples by activation analysis using preconcentration on emission spectroscopic carbon powder

International Nuclear Information System (INIS)

Nagatsuka, Sumiko; Tanizaki, Yoshiyuki

1978-01-01

A simple preconcentration procedure for mercury and copper was examined in the activation analysis of water samples. The preconcentration using pure activated carbon has been reported in several papers. The authors found that the carbon powder for emission spectroscopic analysis showed the high purity equivalent to pure activated carbon. The influence of various parameters in adsorption conditions was studied by radioactive tracers 197 Hg and 64 Cu. It was confirmed that 100% of these elements were adsorbed on carbon powders as pyrrolidine dithiocarbonate complexes at an acidity of pH 6 - 8, the temperature of 50 0 C and the stirring time of 30 minutes. This method was applied to the activation analysis of the river water samples taken from the upper stream area of the Arakawa river and the ground water samples taken from the wells of the environs of Tokyo Megalopolis. The carbon powders which adsorbed these elements were filtered, dried and analyzed by instrumental neutron activation analysis. The Hg concentrations of 0.01 - 0.1 ppb in river water and 0.03 - 1.4 ppb in ground water were obtained as well as the Cu concentrations of 0.3 - 3.0 ppb in ground water. The limits of determination of this method are 0.01 ppb Hg and 0.2 ppb Cu in the case of 1.1 sample of fresh water. (auth.)

Effect of Molecular Weight on the Thermal and Spectroscopic Properties of Poly(vinyl alcohol) Films

International Nuclear Information System (INIS)

Khafagy, R.M.; Abd El-Kader, K.M.; Badr, Y.A.

2009-01-01

Thin films of Poly(vinyl alcohol) (PVA) with molecular weights 5000, 17000,72000 and 125000 g/mol were prepared by casting technique.Samples were thermally and spectroscopically investigated using TGA, DSC, FTIR and FT-Raman spectroscopy, in order to show how the thermal stability and structure of PVA might be correlated with its molecular weight. Thermal analysis showed that samples degrade in two steps mechanism. The mechanism observed for degradation in an inert atmosphere was in accordance with the accepted mechanism of elimination followed by pyrolisation. PVA 5000MW and PVA 17000Mw showed almost similar thermal behavior due to their expected similar structure. PVA 72000Mw showed lower thermal stability since it is characterized with the presence of the unstable C-O-C ether linkages, which lead to the fast melting of this sample. PVA 125000Mw showed the highest thermal stability because crosslinking of the main chains takes place due to introducing additional PVA units, which substitute each over oxygen atom. ΔH values obtained from DSC showed good accordance with TGA and Drtg analysis. Moreover, FTIR and FT-Raman results agreed well with thermal analysis, and confirmed our supposed structural changes which might take place as the molecular weight of the sample changes: since the water uptake, presence of ether linkages, and double bonds formulation due to crosslinking, were confirmed with FTIR and FT-Raman spectral analysis. The crystallinity percentage of the samples was calculated from Raman spectra and results confirmed our spectroscopic explanations. The thermal and spectroscopic behavior of the samples was explained as a result of the competitive action of at least three factors due to increasing the molecular weight: (i) diminution of the existing physical network due to changes in hydrogen bonding; (ii) formation of a chemical network; and (iii) introduction of flexible moieties due to the specific chemical structure after crosslinking

Nuclear resonance vibrational spectroscopic studies of iron-containing biomolecules

International Nuclear Information System (INIS)

Ohta, Takehiro; Seto, Makoto

2014-01-01

In this review, we report recent nuclear resonance vibrational spectroscopic (NRVS) studies of iron-containing biomolecules and their model complexes. The NRVS is synchrotron-based element-specific vibrational spectroscopic methods. Unlike Raman and infrared spectroscopy, the NRVS can investigate all iron motions without selection rules, which provide atomic level insights into the structure/reactivity correlation of biologically relevant iron complexes. (author)

Probing superconductors. Spectroscopic-imaging scanning tunneling microscopy

International Nuclear Information System (INIS)

Hanaguri, Tetsuo

2011-01-01

Discovery of high-temperature superconductivity in a cuprate triggered developments of various spectroscopic tools which have been utilized to elucidate electronic states of this mysterious compound. Particularly, angle-resolved photoemission spectroscopy and scanning-tunneling microscopy/spectroscopy are improved considerably. It is now possible to map the superconducting gap in both momentum and real spaces using these two techniques. Here we review spectroscopic-imaging scanning tunneling microscopy which is able to explore momentum-space phase structure of the superconducting gap, as well as real-space structure. Applications of this technique to a cuprate and an iron-based superconductor are discussed. (author)

HITRAN Application Programming Interface (HAPI): A comprehensive approach to working with spectroscopic data

Science.gov (United States)

Kochanov, R. V.; Gordon, I. E.; Rothman, L. S.; Wcisło, P.; Hill, C.; Wilzewski, J. S.

2016-07-01

The HITRAN Application Programming Interface (HAPI) is presented. HAPI is a free Python library, which extends the capabilities of the HITRANonline interface (www.hitran.org) and can be used to filter and process the structured spectroscopic data. HAPI incorporates a set of tools for spectra simulation accounting for the temperature, pressure, optical path length, and instrument properties. HAPI is aimed to facilitate the spectroscopic data analysis and the spectra simulation based on the line-by-line data, such as from the HITRAN database [JQSRT (2013) 130, 4-50], allowing the usage of the non-Voigt line profile parameters, custom temperature and pressure dependences, and partition sums. The HAPI functions allow the user to control the spectra simulation and data filtering process via a set of the function parameters. HAPI can be obtained at its homepage www.hitran.org/hapi.

Development of laser spectroscopic technology in nuclear industry

International Nuclear Information System (INIS)

Lee, Jong Min; Cha, Byung Heon; Kim, Seong Ho; Cha, Hyung Ki; Lim, Chang Hwan; Song, Kye Seok; Kim, Jung Bok; Rho, Si Pyo; Han, Jae Min; Jeong, Do Yung; Lee, Jong Hoon; Choi, Hwa Lim; Yoo, Byung Duk; Choi, An Sung; Lee, Byung Chul; Kim, Chul Jung

1992-05-01

The goal of this project is to carry out the fundamental researches for the selective photoionization process of heavy atoms as well as the development of experimentally related instruments. Main research results carried out in this year are (1) multi-step photoionization spectroscopy of Hg atom by 3-color 3-step ionization scheme, (2) selective photoionization using polarization spectroscopy, (3) design and construction of ion separator chamber, and (4) theoretical study for spectroscopic parameters of mercury. This technology can be applied to several area of nuclear industry such as the utilization of radioactive waste, the development of new materials, high sensitive analysis of heavy atomic elements. (Author)

Passive Spectroscopic Diagnostics for Magnetically-confined Fusion Plasmas

International Nuclear Information System (INIS)

Stratton, B.C.; Bitter, M.; Hill, K.W.; Hillis, D.L.; Hogan, J.T.

2007-01-01

Spectroscopy of radiation emitted by impurities and hydrogen isotopes plays an important role in the study of magnetically-confined fusion plasmas, both in determining the effects of impurities on plasma behavior and in measurements of plasma parameters such as electron and ion temperatures and densities, particle transport, and particle influx rates. This paper reviews spectroscopic diagnostics of plasma radiation that are excited by collisional processes in the plasma, which are termed 'passive' spectroscopic diagnostics to distinguish them from 'active' spectroscopic diagnostics involving injected particle and laser beams. A brief overview of the ionization balance in hot plasmas and the relevant line and continuum radiation excitation mechanisms is given. Instrumentation in the soft X-ray, vacuum ultraviolet, ultraviolet, visible, and near-infrared regions of the spectrum is described and examples of measurements are given. Paths for further development of these measurements and issues for their implementation in a burning plasma environment are discussed.

Passive Spectroscopic Diagnostics for Magnetically-confined Fusion Plasmas

Energy Technology Data Exchange (ETDEWEB)

Stratton, B. C.; Biter, M.; Hill, K. W.; Hillis, D. L.; Hogan, J. T.

2007-07-18

Spectroscopy of radiation emitted by impurities and hydrogen isotopes plays an important role in the study of magnetically-confined fusion plasmas, both in determining the effects of impurities on plasma behavior and in measurements of plasma parameters such as electron and ion temperatures and densities, particle transport, and particle influx rates. This paper reviews spectroscopic diagnostics of plasma radiation that are excited by collisional processes in the plasma, which are termed 'passive' spectroscopic diagnostics to distinguish them from 'active' spectroscopic diagnostics involving injected particle and laser beams. A brief overview of the ionization balance in hot plasmas and the relevant line and continuum radiation excitation mechanisms is given. Instrumentation in the soft X-ray, vacuum ultraviolet, ultraviolet, visible, and near-infrared regions of the spectrum is described and examples of measurements are given. Paths for further development of these measurements and issues for their implementation in a burning plasma environment are discussed.

Three dimensional nuclear magnetic resonance spectroscopic imaging of sodium ions using stochastic excitation and oscillating gradients

International Nuclear Information System (INIS)

Frederick, B.deB.

1994-12-01

Nuclear magnetic resonance (NMR) spectroscopic imaging of 23 Na holds promise as a non-invasive method of mapping Na + distributions, and for differentiating pools of Na + ions in biological tissues. However, due to NMR relaxation properties of 23 Na in vivo, a large fraction of Na + is not visible with conventional NMR imaging methods. An alternate imaging method, based on stochastic excitation and oscillating gradients, has been developed which is well adapted to measuring nuclei with short T 2 . Contemporary NMR imaging techniques have dead times of up to several hundred microseconds between excitation and sampling, comparable to the shortest in vivo 23 Na T 2 values, causing significant signal loss. An imaging strategy based on stochastic excitation has been developed which greatly reduces experiment dead time by reducing peak radiofrequency (RF) excitation power and using a novel RF circuit to speed probe recovery. Continuously oscillating gradients are used to eliminate transient eddy currents. Stochastic 1 H and 23 Na spectroscopic imaging experiments have been performed on a small animal system with dead times as low as 25μs, permitting spectroscopic imaging with 100% visibility in vivo. As an additional benefit, the encoding time for a 32x32x32 spectroscopic image is under 30 seconds. The development and analysis of stochastic NMR imaging has been hampered by limitations of the existing phase demodulation reconstruction technique. Three dimensional imaging was impractical due to reconstruction time, and design and analysis of proposed experiments was limited by the mathematical intractability of the reconstruction method. A new reconstruction method for stochastic NMR based on Fourier interpolation has been formulated combining the advantage of a several hundredfold reduction in reconstruction time with a straightforward mathematical form

Spectroscopic studies of the molecular parentage of radical species in cometary comae

Science.gov (United States)

Lewis, Benjamin; Pierce, Donna; Cochran, Anita

2015-11-01

We have observed several comets using an integral-field unit spectrograph (the George and Cynthia Mitchell Spectrograph) on the 2.7m Harlan J. Smith telescope at McDonald Observatory. Full-coma spectroscopic images were obtained for various radical species (C2, C3, CH, CN, NH2). By constructing azimuthal average profiles from the full-coma spectroscopic images we can test Haser model parameters with our observations. The Haser model was used to determine production rates and possible parent lifetimes that would be consistent with the model. By iterating through a large range of possible parents lifetimes, we can see what range of values in which the Haser model is consistent with observations. Also, this type of analysis gives us perspective on how sensitive the model's fit quality is to changes in parent lifetimes. Here, we present the work completed to date, and we compare our results to other comet taxonomic surveys.

The Gaia-ESO Survey: double-, triple-, and quadruple-line spectroscopic binary candidates

Science.gov (United States)

Merle, T.; Van Eck, S.; Jorissen, A.; Van der Swaelmen, M.; Masseron, T.; Zwitter, T.; Hatzidimitriou, D.; Klutsch, A.; Pourbaix, D.; Blomme, R.; Worley, C. C.; Sacco, G.; Lewis, J.; Abia, C.; Traven, G.; Sordo, R.; Bragaglia, A.; Smiljanic, R.; Pancino, E.; Damiani, F.; Hourihane, A.; Gilmore, G.; Randich, S.; Koposov, S.; Casey, A.; Morbidelli, L.; Franciosini, E.; Magrini, L.; Jofre, P.; Costado, M. T.; Jeffries, R. D.; Bergemann, M.; Lanzafame, A. C.; Bayo, A.; Carraro, G.; Flaccomio, E.; Monaco, L.; Zaggia, S.

2017-12-01

Context. The Gaia-ESO Survey (GES) is a large spectroscopic survey that provides a unique opportunity to study the distribution of spectroscopic multiple systems among different populations of the Galaxy. Aims: Our aim is to detect binarity/multiplicity for stars targeted by the GES from the analysis of the cross-correlation functions (CCFs) of the GES spectra with spectral templates. Methods: We developed a method based on the computation of the CCF successive derivatives to detect multiple peaks and determine their radial velocities, even when the peaks are strongly blended. The parameters of the detection of extrema (DOE) code have been optimized for each GES GIRAFFE and UVES setup to maximize detection. The DOE code therefore allows to automatically detect multiple line spectroscopic binaries (SBn, n ≥ 2). Results: We apply this method on the fourth GES internal data release and detect 354 SBn candidates (342 SB2, 11 SB3, and even one SB4), including only nine SBs known in the literature. This implies that about 98% of these SBn candidates are new because of their faint visual magnitude that can reach V = 19. Visual inspection of the SBn candidate spectra reveals that the most probable candidates have indeed a composite spectrum. Among the SB2 candidates, an orbital solution could be computed for two previously unknown binaries: CNAME 06404608+0949173 (known as V642 Mon) in NGC 2264 and CNAME 19013257-0027338 in Berkeley 81 (Be 81). A detailed analysis of the unique SB4 (four peaks in the CCF) reveals that CNAME 08414659-5303449 (HD 74438) in the open cluster IC 2391 is a physically bound stellar quadruple system. The SB candidates belonging to stellar clusters are reviewed in detail to discard false detections. We suggest that atmospheric parameters should not be used for these system components; SB-specific pipelines should be used instead. Conclusions: Our implementation of an automatic detection of spectroscopic binaries within the GES has allowed the

Development of a THz spectroscopic imaging system

International Nuclear Information System (INIS)

Usami, M; Iwamoto, T; Fukasawa, R; Tani, M; Watanabe, M; Sakai, K

2002-01-01

We have developed a real-time THz imaging system based on the two-dimensional (2D) electro-optic (EO) sampling technique. Employing the 2D EO-sampling technique, we can obtain THz images using a CCD camera at a video rate of up to 30 frames per second. A spatial resolution of 1.4 mm was achieved. This resolution was reasonably close to the theoretical limit determined by diffraction. We observed not only static objects but also moving ones. To acquire spectroscopic information, time-domain images were collected. By processing these images on a computer, we can obtain spectroscopic images. Spectroscopy for silicon wafers was demonstrated

Spectroscopic data

CERN Document Server

Melzer, J

1976-01-01

During the preparation of this compilation, many people contributed; the compilers wish to thank all of them. In particular they appreciate the efforts of V. Gilbertson, the manuscript typist, and those of K. C. Bregand, J. A. Kiley, and W. H. McPherson, who gave editorial assistance. They would like to thank Dr. J. R. Schwartz for his cooperation and encouragement. In addition, they extend their grati­ tude to Dr. L. Wilson of the Air Force Weapons Laboratory, who gave the initial impetus to this project. v Contents I. I ntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 . . . . . . . . . . . . . . . . 11. Organization ofthe Spectroscopic Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Methods of Production and Experimental Technique . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Band Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2...

A SPECTROSCOPICALLY NORMAL TYPE Ic SUPERNOVA FROM A VERY MASSIVE PROGENITOR

International Nuclear Information System (INIS)

Valenti, Stefano; Pastorello, Andrea; Benetti, Stefano; Cappellaro, Enrico; Tomasella, Lina; Turatto, Massimo; Taubenberger, Stefan; Aramyan, Levon; Botticella, Maria Teresa; Fraser, Morgan; Smartt, Stephen J.; Magill, Lindsay; Kotak, Rubina; Wright, Darryl E.; Elias-Rosa, Nancy; Ergon, Mattias; Sollerman, Jesper; Magnier, Eugene; Price, Paul A.

2012-01-01

We present observations of the Type Ic supernova (SN Ic) 2011bm spanning a period of about one year. The data establish that SN 2011bm is a spectroscopically normal SN Ic with moderately low ejecta velocities and with a very slow spectroscopic and photometric evolution (more than twice as slow as SN 1998bw). The Pan-STARRS1 retrospective detection shows that the rise time from explosion to peak was ∼40 days in the R band. Through an analysis of the light curve and the spectral sequence, we estimate a kinetic energy of ∼7-17 foe and a total ejected mass of ∼7-17 M ☉ , 5-10 M ☉ of which is oxygen and 0.6-0.7 M ☉ is 56 Ni. The physical parameters obtained for SN 2011bm suggest that its progenitor was a massive star of initial mass 30-50 M ☉ . The profile of the forbidden oxygen lines in the nebular spectra shows no evidence of a bi-polar geometry in the ejected material.

Raman spectroscopic analysis of the Maya wall paintings in Ek'Balam, Mexico

Science.gov (United States)

Vandenabeele, P.; Bodé, S.; Alonso, A.; Moens, L.

2005-08-01

Raman spectroscopy has been applied to the examination of wall painting fragments from the archaeological site of Ek'Balam (Yucatán, Mexico). Thirty-three samples have been studied, all originating from room 23 of the Acropolis, and being representative of the painting technique at Ek'Balam during the late Classic Maya period. Several pigments such as haematite, calcite, carbon, cinnabar and indigo were identified in these samples. The latter pigment was presumed to be present as 'Maya blue', which is an intercalation product of indigo and palygorskite clay. The observed Raman spectra are reported and some band assignments have been made. This survey is the first Raman spectroscopic examination of a whole set of pigments in archaeological Maya wall painting fragments.

A Compact, Portable, Reduced-Cost, Gamma Ray Spectroscopic System for Nuclear Verification Final Report CRADA No. TSB-1551-98

Energy Technology Data Exchange (ETDEWEB)

Lavietes, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kalkhoran, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-10-19

The overall goal of this project was to demonstrate a compact gamma-ray spectroscopic system with better energy resolution and lower costs than scintillator-based detector systems for uranium enrichment analysis applications.

Systems budgets architecture and development for the Maunakea Spectroscopic Explorer

Science.gov (United States)

Mignot, Shan; Flagey, Nicolas; Szeto, Kei; Murowinski, Rick; McConnachie, Alan

2016-08-01

The Maunakea Spectroscopic Explorer (MSE) project is an enterprise to upgrade the existing Canada-France- Hawaii observatory into a spectroscopic facility based on a 10 meter-class telescope. As such, the project relies on engineering requirements not limited only to its instruments (the low, medium and high resolution spectrographs) but for the whole observatory. The science requirements, the operations concept, the project management and the applicable regulations are the basis from which these requirements are initially derived, yet they do not form hierarchies as each may serve several purposes, that is, pertain to several budgets. Completeness and consistency are hence the main systems engineering challenges for such a large project as MSE. Special attention is devoted to ensuring the traceability of requirements via parametric models, derivation documents, simulations, and finally maintaining KAOS diagrams and a database under IBM Rational DOORS linking them together. This paper will present the architecture of the main budgets under development and the associated processes, expand to highlight those that are interrelated and how the system, as a whole, is then optimized by modelling and analysis of the pertinent system parameters.

Crystal growth and spectroscopic characterization of Yb3+:LiTaO3

International Nuclear Information System (INIS)

Gruber, John B.; Allik, Toomas H.; Sardar, Dhiraj K.; Yow, Raylon M.; Scripsick, Michael; Wechsler, Barry

2006-01-01

Spectroscopic properties are presented for Yb 3+ incorporated into single crystals of LiTaO 3 grown by the top-seeded solution growth method. From an analysis of the absorption and fluorescence spectra, we are able to determine the Stark-level components of the 2 F 7/2 (the ground-state multiplet manifold) and the 2 F 5/2 (the excited-state multiplet manifold of Yb 3+ (4f 13 )). The room-temperature fluorescence lifetime of 2 F 5/2 is 678μs as measured on a thin sample to reduce possibilities for reabsorption. Spectral comparisons of Yb 3+ -doped LiTaO 3 and LiNbO 3 are drawn. The crystal-field splitting of Yb 3+ (4f 13 ) in both crystal hosts is modeled using a set of crystal-field splitting parameters, B nm , determined from a recent spectroscopic analysis of Er 3+ (4f 11 ) in LiNbO 3 . Without adjustment of the B nm parameters, the model predicts the Stark-level energy and the symmetry label for each level in reasonable agreement with the experimental values. Less photorefractive than its niobate cousin, LiTaO 3 has potential for use in numerous integrated electro-optical circuits and devices

SPECTROSCOPIC ANALYSIS OF AN EIT WAVE/DIMMING OBSERVED BY HINODE/EIS

International Nuclear Information System (INIS)

Chen, F.; Ding, M. D.; Chen, P. F.

2010-01-01

EUV Imaging Telescope (EIT) waves are a wavelike phenomenon propagating outward from the coronal mass ejection source region, with expanding dimmings following behind. We present a spectroscopic study of an EIT wave/dimming event observed by the Hinode/Extreme-ultraviolet Imaging Spectrometer. Although the identification of the wave front is somewhat affected by the pre-existing loop structures, the expanding dimming is well defined. We investigate the line intensity, width, and Doppler velocity for four EUV lines. In addition to the significant blueshift implying plasma outflows in the dimming region as revealed in previous studies, we find that the widths of all four spectral lines increase at the outer edge of the dimmings. We illustrate that this feature can be well explained by the field line stretching model, which claims that EIT waves are apparently moving brightenings that are generated by the successive stretching of the closed field lines.

Noninvasive, near infrared spectroscopic-measured muscle pH and PO2 indicate tissue perfusion for cardiac surgical patients undergoing cardiopulmonary bypass

Science.gov (United States)

Soller, Babs R.; Idwasi, Patrick O.; Balaguer, Jorge; Levin, Steven; Simsir, Sinan A.; Vander Salm, Thomas J.; Collette, Helen; Heard, Stephen O.

2003-01-01

OBJECTIVE: To determine whether near infrared spectroscopic measurement of tissue pH and Po2 has sufficient accuracy to assess variation in tissue perfusion resulting from changes in blood pressure and metabolic demand during cardiopulmonary bypass. DESIGN: Prospective clinical study. SETTING: Academic medical center. SUBJECTS: Eighteen elective cardiac surgical patients. INTERVENTION: Cardiac surgery under cardiopulmonary bypass. MEASUREMENTS AND MAIN RESULTS: A near infrared spectroscopic fiber optic probe was placed over the hypothenar eminence. Reference Po2 and pH sensors were inserted in the abductor digiti minimi (V). Data were collected every 30 secs during surgery and for 6 hrs following cardiopulmonary bypass. Calibration equations developed from one third of the data were used with the remaining data to investigate sensitivity of the near infrared spectroscopic measurement to physiologic changes resulting from cardiopulmonary bypass. Near infrared spectroscopic and reference pH and Po2 measurements were compared for each subject using standard error of prediction. Near infrared spectroscopic pH and Po2 at baseline were compared with values during cardiopulmonary bypass just before rewarming commenced (hypotensive, hypothermic), after rewarming (hypotensive, normothermic) just before discontinuation of cardiopulmonary bypass, and at 6 hrs following cardiopulmonary bypass (normotensive, normothermic) using mixed-model analysis of variance. Near infrared spectroscopic pH and Po2 were well correlated with the invasive measurement of pH (R2 =.84) and Po2 (R 2 =.66) with an average standard error of prediction of 0.022 +/- 0.008 pH units and 6 +/- 3 mm Hg, respectively. The average difference between the invasive and near infrared spectroscopic measurement was near zero for both the pH and Po2 measurements. Near infrared spectroscopic Po2 significantly decreased 50% on initiation of cardiopulmonary bypass and remained depressed throughout the bypass and

Spectroscopic study of low-lying 16N levels

International Nuclear Information System (INIS)

Bardayan, Daniel W.; O'Malley, Patrick; Blackmon, Jeff C.; Chae, K.Y.; Chipps, K.; Cizewski, J.A.; Hatarik, Robert; Jones, K.L.; Kozub, R. L.; Matei, Catalin; Moazen, Brian; Nesaraja, Caroline D.; Pain, Steven D.; Paulauskas, Stanley; Peters, W.A.; Pittman, S.T.; Schmitt, Kyle; Shriner, J.F. Jr.; Smith, Michael Scott

2008-01-01

The magnitude of the 15N(n,gamma)16N reaction rate in asymptotic giant branch stars depends directly on the neutron spectroscopic factors of low-lying 16N levels. A new study of the 15N(d,p)16N reaction is reported populating the ground and first three excited states in 16N. The measured spectroscopic factors are near unity as expected from shell model calculations, resolving a long-standing discrepancy with earlier measurements that had never been confirmed or understood. Updated 15N(n,gamma)16N reaction rates are presented

THE GALACTIC O-STAR SPECTROSCOPIC SURVEY (GOSSS). II. BRIGHT SOUTHERN STARS

International Nuclear Information System (INIS)

Sota, A.; Apellániz, J. Maíz; Alfaro, E. J.; Morrell, N. I.; Barbá, R. H.; Arias, J. I.; Walborn, N. R.; Gamen, R. C.

2014-01-01

We present the second installment of GOSSS, a massive spectroscopic survey of Galactic O stars, based on new homogeneous, high signal-to-noise ratio, R ∼ 2500 digital observations from both hemispheres selected from the Galactic O-Star Catalog (GOSC). In this paper we include bright stars and other objects drawn mostly from the first version of GOSC, all of them south of δ = –20°, for a total number of 258 O stars. We also revise the northern sample of Paper I to provide the full list of spectroscopically classified Galactic O stars complete to B = 8, bringing the total number of published GOSSS stars to 448. Extensive sequences of exceptional objects are given, including the early Of/WN, O Iafpe, Ofc, ON/OC, Onfp, Of?p, and Oe types, as well as double/triple-lined spectroscopic binaries. The new spectral subtype O9.2 is also discussed. The magnitude and spatial distributions of the observed sample are analyzed. We also present new results from OWN, a multi-epoch high-resolution spectroscopic survey coordinated with GOSSS that is assembling the largest sample of Galactic spectroscopic massive binaries ever attained. The OWN data combined with additional information on spectroscopic and visual binaries from the literature indicate that only a very small fraction (if any) of the stars with masses above 15-20 M ☉ are born as single systems. In the future we will publish the rest of the GOSSS survey, which is expected to include over 1000 Galactic O stars

Theory of stellar atmospheres an introduction to astrophysical non-equilibrium quantitative spectroscopic analysis

CERN Document Server

Hubeny, Ivan

2015-01-01

This book provides an in-depth and self-contained treatment of the latest advances achieved in quantitative spectroscopic analyses of the observable outer layers of stars and similar objects. Written by two leading researchers in the field, it presents a comprehensive account of both the physical foundations and numerical methods of such analyses. The book is ideal for astronomers who want to acquire deeper insight into the physical foundations of the theory of stellar atmospheres, or who want to learn about modern computational techniques for treating radiative transfer in non-equilibrium situations. It can also serve as a rigorous yet accessible introduction to the discipline for graduate students.

Sub-THz spectroscopic characterization of vibrational modes in artificially designed DNA monocrystal

International Nuclear Information System (INIS)

Sizov, Igor; Rahman, Masudur; Gelmont, Boris; Norton, Michael L.; Globus, Tatiana

2013-01-01

Highlights: • Sub-THz spectroscopy is used to characterize artificially designed DNA monocrystal. • Results are obtained using a novel near field, RT, frequency domain spectrometer. • Narrow resonances of 0.1 cm −1 width in absorption spectra of crystal are observed. • Signature measured between 310 and 490 GHz is reproducible and well resolved. • Absorption pattern is explained in part by simulation results from dsDNA fragment. - Abstract: Sub-terahertz (sub-THz) vibrational spectroscopy is a new spectroscopic branch for characterizing biological macromolecules. In this work, highly resolved sub-THz resonance spectroscopy is used for characterizing engineered molecular structures, an artificially designed DNA monocrystal, built from a short DNA sequence. Using a recently developed frequency domain spectroscopic instrument operating at room temperature with high spectral and spatial resolution, we demonstrated very intense and specific spectral lines from a DNA crystal in general agreement with a computational molecular dynamics (MD) simulation of a short double stranded DNA fragment. The spectroscopic signature measured in the frequency range between 310 and 490 GHz is rich in well resolved and reproducible spectral features thus demonstrating the capability of THz resonance spectroscopy to be used for characterizing custom macromolecules and structures designed and implemented via nanotechnology for a wide variety of application domains. Analysis of MD simulation indicates that intense and narrow vibrational modes with atomic movements perpendicular (transverse) and parallel (longitudinal) to the long DNA axis coexist in dsDNA, with much higher contribution from longitudinal vibrations

THE BOSS EMISSION-LINE LENS SURVEY (BELLS). I. A LARGE SPECTROSCOPICALLY SELECTED SAMPLE OF LENS GALAXIES AT REDSHIFT {approx}0.5

Energy Technology Data Exchange (ETDEWEB)

Brownstein, Joel R.; Bolton, Adam S.; Pandey, Parul [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Schlegel, David J. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Eisenstein, Daniel J. [Harvard College Observatory, 60 Garden Street, MS 20, Cambridge, MA 02138 (United States); Kochanek, Christopher S. [Department of Astronomy and Center for Cosmology and Astroparticle Physics, Ohio State University, Columbus, OH 43210 (United States); Connolly, Natalia [Department of Physics, Hamilton College, Clinton, NY 13323 (United States); Maraston, Claudia [Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth PO1 3FX (United Kingdom); Seitz, Stella [University Observatory Munich, Scheinstrasse 1, 81679 Muenchen (Germany); Wake, David A. [Department of Astronomy, Yale University, New Haven, CT 06520 (United States); Wood-Vasey, W. Michael [Pittsburgh Center for Particle Physics, Astrophysics, and Cosmology (PITT-PACC), Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA 15260 (United States); Brinkmann, Jon [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349 (United States); Schneider, Donald P. [Department of Astronomy and Astrophysics and Institute for Gravitation and the Cosmos, Pennsylvania State University, University Park, PA 16802 (United States); Weaver, Benjamin A. [Center for Cosmology and Particle Physics, New York University, New York, NY 10003 (United States)

2012-01-01

We present a catalog of 25 definite and 11 probable strong galaxy-galaxy gravitational lens systems with lens redshifts 0.4 {approx}< z {approx}< 0.7, discovered spectroscopically by the presence of higher-redshift emission lines within the Baryon Oscillation Spectroscopic Survey (BOSS) of luminous galaxies, and confirmed with high-resolution Hubble Space Telescope (HST) images of 44 candidates. Our survey extends the methodology of the Sloan Lens Advanced Camera for Surveys survey (SLACS) to higher redshift. We describe the details of the BOSS spectroscopic candidate detections, our HST ACS image processing and analysis methods, and our strong gravitational lens modeling procedure. We report BOSS spectroscopic parameters and ACS photometric parameters for all candidates, and mass-distribution parameters for the best-fit singular isothermal ellipsoid models of definite lenses. Our sample to date was selected using only the first six months of BOSS survey-quality spectroscopic data. The full five-year BOSS database should produce a sample of several hundred strong galaxy-galaxy lenses and in combination with SLACS lenses at lower redshift, strongly constrain the redshift evolution of the structure of elliptical, bulge-dominated galaxies as a function of luminosity, stellar mass, and rest-frame color, thereby providing a powerful test for competing theories of galaxy formation and evolution.

THE FIRST SPECTROSCOPICALLY RESOLVED SUB-PARSEC ORBIT OF A SUPERMASSIVE BINARY BLACK HOLE

Energy Technology Data Exchange (ETDEWEB)

Bon, E.; Jovanovic, P.; Bon, N.; Popovic, L. C. [Astronomical Observatory, Volgina 7, 11060 Belgrade (Serbia); Marziani, P. [INAF, Osservatorio Astronomico di Padova, Padova (Italy); Shapovalova, A. I. [Special Astrophysical Observatory of the Russian AS, Nizhnij Arkhyz, Karachaevo-Cherkesia 369167 (Russian Federation); Borka Jovanovic, V.; Borka, D. [Isaac Newton Institute of Chile, Yugoslavia Branch, Belgrade (Serbia); Sulentic, J. [Instituto de Astrofisica de Andalucia, CSIC, Apdo. 3004, E-18080 Granada (Spain)

2012-11-10

One of the most intriguing scenarios proposed to explain how active galactic nuclei are triggered involves the existence of a supermassive binary black hole (BH) system in their cores. Here, we present an observational evidence for the first spectroscopically resolved sub-parsec orbit of a such system in the core of Seyfert galaxy NGC 4151. Using a method similar to those typically used for spectroscopic binary stars, we obtained radial velocity curves of the supermassive binary system, from which we calculated orbital elements and made estimates about the masses of the components. Our analysis shows that periodic variations in the light and radial velocity curves can be accounted for by an eccentric, sub-parsec Keplerian orbit with a 15.9 year period. The flux maximum in the light curve corresponds to the approaching phase of the secondary component toward the observer. According to the obtained results, we speculate that the periodic variations in the observed H{alpha} line shape and flux are due to shock waves generated by the supersonic motion of the components through the surrounding medium. Given the large observational effort needed to reveal this spectroscopically resolved binary orbital motion, we suggest that many such systems may exist in similar objects even if they are hard to find. Detecting more of them will provide us with insight into the BH mass growth process.

THE FIRST SPECTROSCOPICALLY RESOLVED SUB-PARSEC ORBIT OF A SUPERMASSIVE BINARY BLACK HOLE

International Nuclear Information System (INIS)

Bon, E.; Jovanović, P.; Bon, N.; Popović, L. Č.; Marziani, P.; Shapovalova, A. I.; Borka Jovanović, V.; Borka, D.; Sulentic, J.

2012-01-01

One of the most intriguing scenarios proposed to explain how active galactic nuclei are triggered involves the existence of a supermassive binary black hole (BH) system in their cores. Here, we present an observational evidence for the first spectroscopically resolved sub-parsec orbit of a such system in the core of Seyfert galaxy NGC 4151. Using a method similar to those typically used for spectroscopic binary stars, we obtained radial velocity curves of the supermassive binary system, from which we calculated orbital elements and made estimates about the masses of the components. Our analysis shows that periodic variations in the light and radial velocity curves can be accounted for by an eccentric, sub-parsec Keplerian orbit with a 15.9 year period. The flux maximum in the light curve corresponds to the approaching phase of the secondary component toward the observer. According to the obtained results, we speculate that the periodic variations in the observed Hα line shape and flux are due to shock waves generated by the supersonic motion of the components through the surrounding medium. Given the large observational effort needed to reveal this spectroscopically resolved binary orbital motion, we suggest that many such systems may exist in similar objects even if they are hard to find. Detecting more of them will provide us with insight into the BH mass growth process.

The VANDELS ESO spectroscopic survey

Science.gov (United States)

McLure, R. J.; Pentericci, L.; Cimatti, A.; Dunlop, J. S.; Elbaz, D.; Fontana, A.; Nandra, K.; Amorin, R.; Bolzonella, M.; Bongiorno, A.; Carnall, A. C.; Castellano, M.; Cirasuolo, M.; Cucciati, O.; Cullen, F.; De Barros, S.; Finkelstein, S. L.; Fontanot, F.; Franzetti, P.; Fumana, M.; Gargiulo, A.; Garilli, B.; Guaita, L.; Hartley, W. G.; Iovino, A.; Jarvis, M. J.; Juneau, S.; Karman, W.; Maccagni, D.; Marchi, F.; Mármol-Queraltó, E.; Pompei, E.; Pozzetti, L.; Scodeggio, M.; Sommariva, V.; Talia, M.; Almaini, O.; Balestra, I.; Bardelli, S.; Bell, E. F.; Bourne, N.; Bowler, R. A. A.; Brusa, M.; Buitrago, F.; Caputi, K. I.; Cassata, P.; Charlot, S.; Citro, A.; Cresci, G.; Cristiani, S.; Curtis-Lake, E.; Dickinson, M.; Fazio, G. G.; Ferguson, H. C.; Fiore, F.; Franco, M.; Fynbo, J. P. U.; Galametz, A.; Georgakakis, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Jung, I.; Kim, S.; Koekemoer, A. M.; Khusanova, Y.; Le Fèvre, O.; Lotz, J. M.; Mannucci, F.; Maltby, D. T.; Matsuoka, K.; McLeod, D. J.; Mendez-Hernandez, H.; Mendez-Abreu, J.; Mignoli, M.; Moresco, M.; Mortlock, A.; Nonino, M.; Pannella, M.; Papovich, C.; Popesso, P.; Rosario, D. P.; Salvato, M.; Santini, P.; Schaerer, D.; Schreiber, C.; Stark, D. P.; Tasca, L. A. M.; Thomas, R.; Treu, T.; Vanzella, E.; Wild, V.; Williams, C. C.; Zamorani, G.; Zucca, E.

2018-05-01

VANDELS is a uniquely-deep spectroscopic survey of high-redshift galaxies with the VIMOS spectrograph on ESO's Very Large Telescope (VLT). The survey has obtained ultra-deep optical (0.48 studies. Using integration times calculated to produce an approximately constant signal-to-noise ratio (20 motivation, survey design and target selection.

Raman spectroscopic signature of vaginal fluid and its potential application in forensic body fluid identification.

Science.gov (United States)

Sikirzhytskaya, Aliaksandra; Sikirzhytski, Vitali; Lednev, Igor K

2012-03-10

Traces of human body fluids, such as blood, saliva, sweat, semen and vaginal fluid, play an increasingly important role in forensic investigations. However, a nondestructive, easy and rapid identification of body fluid traces at the scene of a crime has not yet been developed. The obstacles have recently been addressed in our studies, which demonstrated the considerable potential of Raman spectroscopy. In this study, we continued to build a full library of body fluid spectroscopic signatures. The problems concerning vaginal fluid stain identification were addressed using Raman spectroscopy coupled with advanced statistical analysis. Calculated characteristic Raman and fluorescent spectral components were used to build a multidimensional spectroscopic signature of vaginal fluid, which demonstrated good specificity and was able to handle heterogeneous samples from different donors. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

The HITRAN 2008 molecular spectroscopic database

International Nuclear Information System (INIS)

Rothman, L.S.; Gordon, I.E.; Barbe, A.; Benner, D.Chris; Bernath, P.F.; Birk, M.; Boudon, V.; Brown, L.R.; Campargue, A.; Champion, J.-P.; Chance, K.; Coudert, L.H.; Dana, V.; Devi, V.M.; Fally, S.; Flaud, J.-M.

2009-01-01

This paper describes the status of the 2008 edition of the HITRAN molecular spectroscopic database. The new edition is the first official public release since the 2004 edition, although a number of crucial updates had been made available online since 2004. The HITRAN compilation consists of several components that serve as input for radiative-transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e. spectra in which the individual lines are not resolved; individual line parameters and absorption cross-sections for bands in the ultraviolet; refractive indices of aerosols, tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 42 molecules including many of their isotopologues.

Mid-infrared spectroscopic investigation

International Nuclear Information System (INIS)

Walter, L.; Vergo, N.; Salisbury, J.W.

1987-01-01

Mid-infrared spectroscopic research efforts are discussed. The development of a new instrumentation to permit advanced measurements in the mid-infrared region of the spectrum, the development of a special library of well-characterized mineral and rock specimens for interpretation of remote sensing data, and cooperative measurements of the spectral signatures of analogues of materials that may be present on the surfaces of asteroids, planets or their Moons are discussed

Chemical mapping of pharmaceutical cocrystals using terahertz spectroscopic imaging.

Science.gov (United States)

Charron, Danielle M; Ajito, Katsuhiro; Kim, Jae-Young; Ueno, Yuko

2013-02-19

Terahertz (THz) spectroscopic imaging is a promising technique for distinguishing pharmaceuticals of similar molecular composition but differing crystal structures. Physicochemical properties, for instance bioavailability, are manipulated by altering a drug's crystal structure through methods such as cocrystallization. Cocrystals are molecular complexes having crystal structures different from those of their pure components. A technique for identifying the two-dimensional distribution of these alternate forms is required. Here we present the first demonstration of THz spectroscopic imaging of cocrystals. THz spectra of caffeine-oxalic acid cocrystal measured at low temperature exhibit sharp peaks, enabling us to visualize the cocrystal distribution in nonuniform tablets. The cocrystal distribution was clearly identified using THz spectroscopic data, and the cocrystal concentration was calculated with 0.3-1.3% w/w error from the known total concentration. From this result, THz spectroscopy allows quantitative chemical mapping of cocrystals and offers researchers and drug developers a new analytical tool.

Excel2Genie: A Microsoft Excel application to improve the flexibility of the Genie-2000 Spectroscopic software

International Nuclear Information System (INIS)

Forgács, Attila; Balkay, László; Trón, Lajos; Raics, Péter

2014-01-01

Excel2Genie, a simple and user-friendly Microsoft Excel interface, has been developed to the Genie-2000 Spectroscopic Software of Canberra Industries. This Excel application can directly control Canberra Multichannel Analyzer (MCA), process the acquired data and visualize them. Combination of Genie-2000 with Excel2Genie results in remarkably increased flexibility and a possibility to carry out repetitive data acquisitions even with changing parameters and more sophisticated analysis. The developed software package comprises three worksheets: display parameters and results of data acquisition, data analysis and mathematical operations carried out on the measured gamma spectra. At the same time it also allows control of these processes. Excel2Genie is freely available to assist gamma spectrum measurements and data evaluation by the interested Canberra users. With access to the Visual Basic Application (VBA) source code of this application users are enabled to modify the developed interface according to their intentions. - Highlights: • User-friendly Microsoft Excel interface to the Genie-2000 Spectroscopic software. • Data acquisitions with changing parameters and sophisticated data analysis. • Three worksheets: data acquisition, data analysis and mathematical operations on spectra. • The source code is freely available

Spectroscopic methods for characterization of nuclear fuels

International Nuclear Information System (INIS)

Sastry, M.D.

1999-01-01

Spectroscopic techniques have contributed immensely in the characterisation and speciation of materials relevant to a variety of applications. These techniques have time tested credentials and continue to expand into newer areas. In the field of nuclear fuel fabrication, atomic spectroscopic methods are used for monitoring the trace metallic constituents in the starting materials and end product, and for monitoring process pick up. The current status of atomic spectroscopic methods for the determination of trace metallic constituents in nuclear fuel materials will be briefly reviewed and new approaches will be described with a special emphasis on inductively coupled plasma techniques and ETV-ICP-AES hyphenated techniques. Special emphasis will also be given in highlighting the importance of chemical separation procedures for the optimum utilization of potential of ICP. The presentation will also include newer techniques like Photo Acoustic Spectroscopy, and Electron Paramagnetic Resonance (EPR) Imaging. PAS results on uranium and plutonium oxides will be described with a reference to the determination of U 4+ /U 6+ concentration in U 3 O 8 . EPR imaging techniques for speciation and their spatial distribution in solids will be described and its potential use for Gd 3+ containing UO 2 pellets (used for flux flattening) will be highlighted. (author)

Instrumental analysis of bacterial cells using vibrational and emission Moessbauer spectroscopic techniques

International Nuclear Information System (INIS)

Kamnev, Alexander A.; Tugarova, Anna V.; Antonyuk, Lyudmila P.; Tarantilis, Petros A.; Kulikov, Leonid A.; Perfiliev, Yurii D.; Polissiou, Moschos G.; Gardiner, Philip H.E.

2006-01-01

In biosciences and biotechnology, the expanding application of physicochemical approaches using modern instrumental techniques is an efficient strategy to obtain valuable and often unique information at the molecular level. In this work, we applied a combination of vibrational (Fourier transform infrared (FTIR), FT-Raman) spectroscopic techniques, useful in overall structural and compositional analysis of bacterial cells of the rhizobacterium Azospirillum brasilense, with 57 Co emission Moessbauer spectroscopy (EMS) used for sensitive monitoring of metal binding and further transformations in live bacterial cells. The information obtained, together with ICP-MS analyses for metals taken up by the bacteria, is useful in analysing the impact of the environmental conditions (heavy metal stress) on the bacterial metabolism and some differences in the heavy metal stress-induced behaviour of non-endophytic (Sp7) and facultatively endophytic (Sp245) strains. The results show that, while both strains Sp7 and Sp245 take up noticeable and comparable amounts of heavy metals from the medium (0.12 and 0.13 mg Co, 0.48 and 0.44 mg Cu or 4.2 and 2.1 mg Zn per gram of dry biomass, respectively, at a metal concentration of 0.2 mM in the medium), their metabolic responses differ essentially. Whereas for strain Sp7 the FTIR measurements showed significant accumulation of polyhydroxyalkanoates as storage materials involved in stress endurance, strain Sp245 did not show any major changes in cellular composition. Nevertheless, EMS measurements showed rapid binding of cobalt(II) by live bacterial cells (chemically similar to metal binding by dead bacteria) and its further transformation in the live cells within an hour

Instrumental analysis of bacterial cells using vibrational and emission Moessbauer spectroscopic techniques

Energy Technology Data Exchange (ETDEWEB)

Kamnev, Alexander A. [Laboratory of Biochemistry of Plant-Bacterial Symbioses, Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 410049 Saratov (Russian Federation)]. E-mail: aakamnev@ibppm.sgu.ru; Tugarova, Anna V. [Laboratory of Biochemistry of Plant-Bacterial Symbioses, Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 410049 Saratov (Russian Federation); Antonyuk, Lyudmila P. [Laboratory of Biochemistry of Plant-Bacterial Symbioses, Institute of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, 410049 Saratov (Russian Federation); Tarantilis, Petros A. [Laboratory of Chemistry, Department of Science, Agricultural University of Athens, 11855 Athens (Greece); Kulikov, Leonid A. [Laboratory of Nuclear Chemistry Techniques, Department of Radiochemistry, Faculty of Chemistry, M.V. Lomonosov Moscow State University, 119992 Moscow (Russian Federation); Perfiliev, Yurii D. [Laboratory of Nuclear Chemistry Techniques, Department of Radiochemistry, Faculty of Chemistry, M.V. Lomonosov Moscow State University, 119992 Moscow (Russian Federation); Polissiou, Moschos G. [Laboratory of Chemistry, Department of Science, Agricultural University of Athens, 11855 Athens (Greece); Gardiner, Philip H.E. [Division of Chemistry, School of Science and Mathematics, Sheffield Hallam University, Sheffield S1 1WB (United Kingdom)

2006-07-28

In biosciences and biotechnology, the expanding application of physicochemical approaches using modern instrumental techniques is an efficient strategy to obtain valuable and often unique information at the molecular level. In this work, we applied a combination of vibrational (Fourier transform infrared (FTIR), FT-Raman) spectroscopic techniques, useful in overall structural and compositional analysis of bacterial cells of the rhizobacterium Azospirillum brasilense, with {sup 57}Co emission Moessbauer spectroscopy (EMS) used for sensitive monitoring of metal binding and further transformations in live bacterial cells. The information obtained, together with ICP-MS analyses for metals taken up by the bacteria, is useful in analysing the impact of the environmental conditions (heavy metal stress) on the bacterial metabolism and some differences in the heavy metal stress-induced behaviour of non-endophytic (Sp7) and facultatively endophytic (Sp245) strains. The results show that, while both strains Sp7 and Sp245 take up noticeable and comparable amounts of heavy metals from the medium (0.12 and 0.13 mg Co, 0.48 and 0.44 mg Cu or 4.2 and 2.1 mg Zn per gram of dry biomass, respectively, at a metal concentration of 0.2 mM in the medium), their metabolic responses differ essentially. Whereas for strain Sp7 the FTIR measurements showed significant accumulation of polyhydroxyalkanoates as storage materials involved in stress endurance, strain Sp245 did not show any major changes in cellular composition. Nevertheless, EMS measurements showed rapid binding of cobalt(II) by live bacterial cells (chemically similar to metal binding by dead bacteria) and its further transformation in the live cells within an hour.

Spectroscopic analysis and efficient diode-pumped 1.9 μm Tm3+-doped β'-Gd2(MoO4)3 crystal laser.

Science.gov (United States)

Tang, Jianfeng; Chen, Yujin; Lin, Yanfu; Gong, Xinghong; Huang, Jianhua; Luo, Zundu; Huang, Yidong

2011-07-04

Tm3+-doped β'-Gd2(MoO4)3 single crystal was grown by the Czochralski method. Spectroscopic analysis was carried out along different polarizations. End-pumped by a quasi-cw diode laser at 795 nm in a plano-concave cavity, an average laser output power of 58 mW around 1.9 μm was achieved in a 0.93-mm-thick crystal when the output coupler transmission was 7.1%. The absorbed pump threshold was 8 mW and the slope efficiency of the laser was 57%. This crystal has smooth and broad gain curve around 1.9 μm, which shows that it is also a potential gain medium for tunable and short pulse lasers.

Universal relation between spectroscopic constants

Indian Academy of Sciences (India)

(3) The author has used eq. (6) of his paper to calculate De. This relation leads to a large deviation from the correct value depending upon the extent to which experimental values are known. Guided by this fact, in our work, we used experimentally observed De values to derive the relation between spectroscopic constants.

Spectroscopic Tools Applied to Element Z = 115 Decay Chains

Directory of Open Access Journals (Sweden)

Forsberg U.

2014-03-01

Full Text Available Nuclides that are considered to be isotopes of element Z = 115 were produced in the reaction 48Ca + 243Am at the GSI Helmholtzzentrum für Schwerionenforschung Darmstadt. The detector setup TASISpec was used. It was mounted behind the gas-filled separator TASCA. Thirty correlated α-decay chains were found, and the energies of the particles were determined with high precision. Two important spectroscopic aspects of the offline data analysis are discussed in detail: the handling of digitized preamplified signals from the silicon strip detectors, and the energy reconstruction of particles escaping to upstream detectors relying on pixel-by-pixel dead-layer thicknesses.

Spectroscopic analysis on the binding interaction between tetracycline hydrochloride and bovine proteins β-casein, α-lactalbumin

Energy Technology Data Exchange (ETDEWEB)

Bi, Hongna; Tang, Lin, E-mail: tanglin@sdnu.edu.cn; Gao, Xin; Jia, Jingjing; Lv, Henghui

2016-10-15

We investigated the binding interaction between tetracycline hydrochloride (TCH) and bovine proteins β-casein (β-CN), α-lactalbumin (α-LA) in aqueous solution by multi-spectroscopic methods and molecular modeling techniques. Fluorescence and time-resolved fluorescence showed that TCH effectively quenched the intrinsic fluorescence of bovine proteins via static quenching, while there was a single class of binding site on protein. Thermodynamic parameters revealed that electrostatic forces played major roles in the interaction between β-CN and TCH, whereas α-LA-TCH complex were stabilized by hydrogen bonds and van der Waals forces. Moreover, circular dichroism spectra (CD spectra), ultraviolet visible absorption spectra (UV–vis absorption spectra), and fluorescence Excitation-Emission Matrix (EEM) spectra results indicated the secondary structure of bovine proteins was changed in the presence of TCH with the α-helix percentage of protein-TCH complexes decreased. Molecular modeling analysis supported the experimental results well. In addition, the research of surface hydrophobicity further verified tertiary structure of proteins was changed in the presence of TCH and the possible changes of protein function. These results achieved from experiments may be valuable in the milk industry and food safety.

Spectroscopic analysis on the binding interaction between tetracycline hydrochloride and bovine proteins β-casein, α-lactalbumin

International Nuclear Information System (INIS)

Bi, Hongna; Tang, Lin; Gao, Xin; Jia, Jingjing; Lv, Henghui

2016-01-01

We investigated the binding interaction between tetracycline hydrochloride (TCH) and bovine proteins β-casein (β-CN), α-lactalbumin (α-LA) in aqueous solution by multi-spectroscopic methods and molecular modeling techniques. Fluorescence and time-resolved fluorescence showed that TCH effectively quenched the intrinsic fluorescence of bovine proteins via static quenching, while there was a single class of binding site on protein. Thermodynamic parameters revealed that electrostatic forces played major roles in the interaction between β-CN and TCH, whereas α-LA-TCH complex were stabilized by hydrogen bonds and van der Waals forces. Moreover, circular dichroism spectra (CD spectra), ultraviolet visible absorption spectra (UV–vis absorption spectra), and fluorescence Excitation-Emission Matrix (EEM) spectra results indicated the secondary structure of bovine proteins was changed in the presence of TCH with the α-helix percentage of protein-TCH complexes decreased. Molecular modeling analysis supported the experimental results well. In addition, the research of surface hydrophobicity further verified tertiary structure of proteins was changed in the presence of TCH and the possible changes of protein function. These results achieved from experiments may be valuable in the milk industry and food safety.

Nonplanar property study of antifungal agent tolnaftate-spectroscopic approach

Science.gov (United States)

Arul Dhas, D.; Hubert Joe, I.; Roy, S. D. D.; Balachandran, S.

2011-09-01

Vibrational analysis of the thionocarbamate fungicide tolnaftate which is antidermatophytic, antitrichophytic and antimycotic agent, primarily inhibits the ergosterol biosynthesis in the fungus, was carried out using NIR FT-Raman and FTIR spectroscopic techniques. The equilibrium geometry, various bonding features, harmonic vibrational wavenumbers and torsional potential energy surface (PES) scan studies have been computed using density functional theory method. The detailed interpretation of the vibrational spectra has been carried out with the aid of VEDA.4 program. Vibrational spectra, natural bonding orbital (NBO) analysis and optimized molecular structure show the clear evidence for electronic interaction of thionocarbamate group with aromatic ring. Predicted electronic absorption spectrum from TD-DFT calculation has been compared with the UV-vis spectrum. The Mulliken population analysis on atomic charges and the HOMO-LUMO energy were also calculated. Vibrational analysis reveals that the simultaneous IR and Raman activation of the C-C stretching mode in the phenyl and naphthalene ring provide evidence for the charge transfer interaction between the donor and acceptor groups and is responsible for its bioactivity as a fungicide.

Bio-medical X-ray imaging with spectroscopic pixel detectors

CERN Document Server

Butler, A P H; Tipples, R; Cook, N; Watts, R; Meyer, J; Bell, A J; Melzer, T R; Butler, P H

2008-01-01

The aim of this study is to review the clinical potential of spectroscopic X-ray detectors and to undertake a feasibility study using a novel detector in a clinical hospital setting. Detectors currently in development, such as Medipix-3, will have multiple energy thresholds allowing for routine use of spectroscopic bio-medical imaging. We have coined the term MARS (Medipix All Resolution System) for bio-medical images that provide spatial, temporal, and energy information. The full clinical significance of spectroscopic X-ray imaging is difficult to predict but insights can be gained by examining both image reconstruction artifacts and the current uses of dual-energy techniques. This paper reviews the known uses of energy information in vascular imaging and mammography, clinically important fields. It then presents initial results from using Medipix-2, to image human tissues within a clinical radiology department. Detectors currently in development, such as Medipix-3, will have multiple energy thresholds allo...

Very large area multiwire spectroscopic proportional counters

International Nuclear Information System (INIS)

Ubertini, P.; Bazzano, A.; Boccaccini, L.; Mastropietro, M.; La Padula, C.D.; Patriarca, R.; Polcaro, V.F.

1981-01-01

As a result of a five year development program, a final prototype of a Very Large Area Spectroscopic Proportional Counter (VLASPC), to be employed in space borne payloads, was produced at the Istituto di Astrofisica Spaziale, Frascati. The instrument is the last version of a new generation of Multiwire Spectroscopic Proportional Counters (MWSPC) succesfully employed in many balloon borne flights, devoted to hard X-ray astronomy. The sensitive area of this standard unit is 2700 cm 2 with an efficiency higher than 10% in the range 15-180 keV (80% at 60 keV). The low cost and weight make this new type of VLASPC competitive with Nal arrays, phoswich and GSPC detectors in terms of achievable scientific results. (orig.)

Very large area multiwire spectroscopic proportional counters

Energy Technology Data Exchange (ETDEWEB)

Ubertini, P.; Bazzano, A.; Boccaccini, L.; Mastropietro, M.; La Padula, C.D.; Patriarca, R.; Polcaro, V.F. (Istituto di Astrofisica Spaziale, Frascati (Italy))

1981-07-01

As a result of a five year development program, a final prototype of a Very Large Area Spectroscopic Proportional Counter (VLASPC), to be employed in space borne payloads, was produced at the Istituto di Astrofisica Spaziale, Frascati. The instrument is the last version of a new generation of Multiwire Spectroscopic Proportional Counters (MWSPC) successfully employed in many balloon borne flights, devoted to hard X-ray astronomy. The sensitive area of this standard unit is 2700 cm/sup 2/ with an efficiency higher than 10% in the range 15-180 keV (80% at 60 keV). The low cost and weight make this new type of VLASPC competitive with Nal arrays, phoswich and GSPC detectors in terms of achievable scientific results.

Spectroscopic and shadowgraphic analysis of laser induced plasmas in the orthogonal double pulse pre-ablation configuration

International Nuclear Information System (INIS)

Cristoforetti, G.; Legnaioli, S.; Pardini, L.; Palleschi, V.; Salvetti, A.; Tognoni, E.

2006-01-01

This work focuses on the study of the plumes obtained in the double pulse orthogonal Laser Induced Breakdown Spectroscopy (LIBS) in the pre-ablation configuration using both spectroscopic and shadowgraphic approaches. Single and double pulse LIBS experiments were carried out on a brass sample in air. Both the distance of the air plasma from the target surface and the interpulse delay were varied (respectively in the range 0.1-4.2 mm and up to 50 μs) revealing a significant variation of the plasma emission and of the plume-shock wave dynamical expansion in different cases. The intensity of both atomic and ionized zinc lines was measured in all the cases, allowing the calculation of the spatially averaged temperature and electron density and an estimation of the ablated mass. The line intensities and the thermodynamic parameters obtained by the spectroscopic measurements were discussed bearing in mind the dynamical expansion characteristics obtained from the shadowgraphic approach. All the data seem to be consistent with the model previously proposed for the double pulse collinear configuration where the line enhancement is mainly attributed to the ambient gas rarefaction produced by the first laser pulse, which causes a less effective shielding of the second laser pulse

A Keck/DEIMOS spectroscopic survey of the faint M31 satellites AndIX, AndXI, AndXII and AndXIII†

Science.gov (United States)

Collins, M. L. M.; Chapman, S. C.; Irwin, M. J.; Martin, N. F.; Ibata, R. A.; Zucker, D. B.; Blain, A.; Ferguson, A. M. N.; Lewis, G. F.; McConnachie, A. W.; Peñarrubia, J.

2010-10-01

We present the first spectroscopic analysis of the faint M31 satellite galaxies, AndXI and AndXIII, as well as a re-analysis of existing spectroscopic data for two further faint companions, AndIX (correcting for an error in earlier geometric modelling that caused a misclassification of member stars in previous work) and AndXII. By combining data obtained using the Deep Imaging Multi-Object Spectrograph (DEIMOS) mounted on the Keck II telescope with deep photometry from the Suprime-Cam instrument on Subaru, we have identified the most probable members for each of the satellites based on their radial velocities (precise to several down to i ~ 22), distance from the centre of the dwarf spheroidal galaxies (dSphs) and their photometric [Fe/H]. Using both the photometric and spectroscopic data, we have also calculated global properties for the dwarfs, such as systemic velocities, metallicities and half-light radii. We find each dwarf to be very metal poor ([Fe/H] ~ -2 both photometrically and spectroscopically, from their stacked spectrum), and as such, they continue to follow the luminosity-metallicity relationship established with brighter dwarfs. We are unable to resolve dispersion for AndXI due to small sample size and low signal-to-noise ratio, but we set a 1σ upper limit of σv financial support of the W.M. Keck Foundation. Based in part on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. ‡ E-mail: mlmc2@ast.cam.ac.uk

Spectroscopic investigations on oxidized multi-walled carbon nanotubes

Energy Technology Data Exchange (ETDEWEB)

Anandhi, C. M. S.; Premkumar, S.; Asath, R. Mohamed; Mathavan, T.; Benial, A. Milton Franklin, E-mail: miltonfranklin@yahoo.com [Department of Physics, N.M.S.S.V.N. College, Madurai-625 019, Tamil Nadu (India)

2016-05-06

The pristine multi-walled carbon nanotubes (MWCNTs) were oxidized by the ultrasonication process. The oxidized MWCNTs were characterized by the X-ray diffraction (XRD), ultraviolet–visible (UV-Vis) and Fourier transform -Raman (FT-Raman) spectroscopic techniques. The XRD analysis confirms that the oxidized MWCNTs exist in a hexagonal structure and the sharp XRD peak corresponds to the (002) Bragg’s reflection plane, which indicates that the MWCNTs have higher crystalline nature. The UV-Vis analysis confirms that the MWCNTs functionalized with the carboxylic acid. The red shift was observed corresponds to the D band in the Raman spectrum, which reveals that the reduced disordered graphitic structure of oxidized MWCNTs. The strong Raman peak was observed at 2563 cm{sup -1} corresponds to the overtone of the D band, which is the characteristic vibrational mode of oxidized MWCNTs. The carboxylic acid functionalization of MWCNTs enhances the dispersibility, which paves the way for potential applications in the field of biosensors and targeted drug delivery.

The IACOB project. V. Spectroscopic parameters of the O-type stars in the modern grid of standards for spectral classification

Science.gov (United States)

Holgado, G.; Simón-Díaz, S.; Barbá, R. H.; Puls, J.; Herrero, A.; Castro, N.; Garcia, M.; Maíz Apellániz, J.; Negueruela, I.; Sabín-Sanjulián, C.

2018-06-01

Context. The IACOB and OWN surveys are two ambitious, complementary observational projects which have made available a large multi-epoch spectroscopic database of optical high resolution spectra of Galactic massive O-type stars. Aims: Our aim is to study the full sample of (more than 350) O stars surveyed by the IACOB and OWN projects. As a first step towards this aim, we have performed the quantitative spectroscopic analysis of a subsample of 128 stars included in the modern grid of O-type standards for spectral classification. The sample comprises stars with spectral types in the range O3-O9.7 and covers all luminosity classes. Methods: We used the semi-automatized IACOB-BROAD and IACOB-GBAT/FASTWIND tools to determine the complete set of spectroscopic parameters that can be obtained from the optical spectrum of O-type stars. A quality flag was assigned to the outcome of the IACOB-GBAT/FASTWIND analysis for each star, based on a visual evaluation of how the synthetic spectrum of the best fitting FASTWIND model reproduces the observed spectrum. We also benefitted from the multi-epoch character of the IACOB and OWN surveys to perform a spectroscopic variability study of the complete sample, providing two different flags for each star accounting for spectroscopic binarity as well as variability of the main wind diagnostic lines. Results: We obtain - for the first time in a homogeneous and complete manner - the full set of spectroscopic parameters of the "anchors" of the spectral classification system in the O star domain. We provide a general overview of the stellar and wind parameters of this reference sample, as well as updated recipes for the SpT-Teff and SpT-log g calibrations for Galactic O-type stars. We also propose a distance-independent test for the wind-momentum luminosity relationship. We evaluate the reliability of our semi-automatized analysis strategy using a subsample of 40 stars extensively studied in the literature, and find a fairly good agreement

Characterization of cytochrome c as marker for retinal cell degeneration by uv/vis spectroscopic imaging

Science.gov (United States)

Hollmach, Julia; Schweizer, Julia; Steiner, Gerald; Knels, Lilla; Funk, Richard H. W.; Thalheim, Silko; Koch, Edmund

2011-07-01

Retinal diseases like age-related macular degeneration have become an important cause of visual loss depending on increasing life expectancy and lifestyle habits. Due to the fact that no satisfying treatment exists, early diagnosis and prevention are the only possibilities to stop the degeneration. The protein cytochrome c (cyt c) is a suitable marker for degeneration processes and apoptosis because it is a part of the respiratory chain and involved in the apoptotic pathway. The determination of the local distribution and oxidative state of cyt c in living cells allows the characterization of cell degeneration processes. Since cyt c exhibits characteristic absorption bands between 400 and 650 nm wavelength, uv/vis in situ spectroscopic imaging was used for its characterization in retinal ganglion cells. The large amount of data, consisting of spatial and spectral information, was processed by multivariate data analysis. The challenge consists in the identification of the molecular information of cyt c. Baseline correction, principle component analysis (PCA) and cluster analysis (CA) were performed in order to identify cyt c within the spectral dataset. The combination of PCA and CA reveals cyt c and its oxidative state. The results demonstrate that uv/vis spectroscopic imaging in conjunction with sophisticated multivariate methods is a suitable tool to characterize cyt c under in situ conditions.

QUANTIFYING THE BIASES OF SPECTROSCOPICALLY SELECTED GRAVITATIONAL LENSES

International Nuclear Information System (INIS)

Arneson, Ryan A.; Brownstein, Joel R.; Bolton, Adam S.

2012-01-01

Spectroscopic selection has been the most productive technique for the selection of galaxy-scale strong gravitational lens systems with known redshifts. Statistically significant samples of strong lenses provide a powerful method for measuring the mass-density parameters of the lensing population, but results can only be generalized to the parent population if the lensing selection biases are sufficiently understood. We perform controlled Monte Carlo simulations of spectroscopic lens surveys in order to quantify the bias of lenses relative to parent galaxies in velocity dispersion, mass axis ratio, and mass-density profile. For parameters typical of the SLACS and BELLS surveys, we find (1) no significant mass axis ratio detection bias of lenses relative to parent galaxies; (2) a very small detection bias toward shallow mass-density profiles, which is likely negligible compared to other sources of uncertainty in this parameter; (3) a detection bias toward smaller Einstein radius for systems drawn from parent populations with group- and cluster-scale lensing masses; and (4) a lens-modeling bias toward larger velocity dispersions for systems drawn from parent samples with sub-arcsecond mean Einstein radii. This last finding indicates that the incorporation of velocity-dispersion upper limits of non-lenses is an important ingredient for unbiased analyses of spectroscopically selected lens samples. In general, we find that the completeness of spectroscopic lens surveys in the plane of Einstein radius and mass-density profile power-law index is quite uniform, up to a sharp drop in the region of large Einstein radius and steep mass-density profile, and hence that such surveys are ideally suited to the study of massive field galaxies.

Application of second derivative spectroscopy for increasing molecular specificity of Fourier transform infrared spectroscopic imaging of articular cartilage.

Science.gov (United States)

Rieppo, L; Saarakkala, S; Närhi, T; Helminen, H J; Jurvelin, J S; Rieppo, J

2012-05-01

Fourier transform infrared (FT-IR) spectroscopic imaging is a promising method that enables the analysis of spatial distribution of biochemical components within histological sections. However, analysis of FT-IR spectroscopic data is complicated since absorption peaks often overlap with each other. Second derivative spectroscopy is a technique which enhances the separation of overlapping peaks. The objective of this study was to evaluate the specificity of the second derivative peaks for the main tissue components of articular cartilage (AC), i.e., collagen and proteoglycans (PGs). Histological bovine AC sections were measured before and after enzymatic removal of PGs. Both formalin-fixed sections (n = 10) and cryosections (n = 6) were investigated. Relative changes in the second derivative peak heights caused by the removal of PGs were calculated for both sample groups. The results showed that numerous peaks, e.g., peaks located at 1202 cm(-1) and 1336 cm(-1), altered less than 5% in the experiment. These peaks were assumed to be specific for collagen. In contrast, two peaks located at 1064 cm(-1) and 1376 cm(-1) were seen to alter notably, approximately 50% or more. These peaks were regarded to be specific for PGs. The changes were greater in cryosections than formalin-fixed sections. The results of this study suggest that the second derivative spectroscopy offers a practical and more specific method than routinely used absorption spectrum analysis methods to obtain compositional information on AC with FT-IR spectroscopic imaging. Copyright © 2012 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Clinical stage T1c prostate cancer: evaluation with endorectal MR imaging and MR spectroscopic imaging.

Science.gov (United States)

Zhang, Jingbo; Hricak, Hedvig; Shukla-Dave, Amita; Akin, Oguz; Ishill, Nicole M; Carlino, Lauren J; Reuter, Victor E; Eastham, James A

2009-11-01

To assess the diagnostic accuracy of endorectal magnetic resonance (MR) imaging and MR spectroscopic imaging for prediction of the pathologic stage of prostate cancer and the presence of clinically nonimportant disease in patients with clinical stage T1c prostate cancer. The institutional review board approved-and waived the informed patient consent requirement for-this HIPAA-compliant study involving 158 patients (median age, 58 years; age range, 40-76 years) who had clinical stage T1c prostate cancer, had not been treated preoperatively, and underwent combined 1.5-T endorectal MR imaging-MR spectroscopic imaging between January 2003 and March 2004 before undergoing radical prostatectomy. On the MR images and combined endorectal MR-MR spectroscopic images, two radiologists retrospectively and independently rated the likelihood of cancer in 12 prostate regions and the likelihoods of extracapsular extension (ECE), seminal vesicle invasion (SVI), and adjacent organ invasion by using a five-point scale, and they determined the probability of clinically nonimportant prostate cancer by using a four-point scale. Whole-mount step-section pathology maps were used for imaging-pathologic analysis correlation. Receiver operating characteristic curves were constructed and areas under the curves (AUCs) were estimated nonparametrically for assessment of reader accuracy. At surgical-pathologic analysis, one (0.6%) patient had no cancer; 124 (78%) patients, organ-confined (stage pT2) disease; 29 (18%) patients, ECE (stage pT3a); two (1%) patients, SVI (stage pT3b); and two (1%) patients, bladder neck invasion (stage pT4). Forty-six (29%) patients had a total tumor volume of less than 0.5 cm(3). With combined MR imaging-MR spectroscopic imaging, the two readers achieved 80% accuracy in disease staging and AUCs of 0.62 and 0.71 for the prediction of clinically nonimportant cancer. Clinical stage T1c prostate cancers are heterogeneous in pathologic stage and volume. MR imaging may

Technical report for fabrication and performance test of electrochemical/spectroscopic measurement system

International Nuclear Information System (INIS)

Park, Yong Joon; Cho, Young Hwan; Bae, Sang Eun; Im, Hee Jung; Song, Kyu Seok

2010-01-01

Development of evaluation technology of electrochemical reactions is very essential to understand chemical behavior of actinides and lanthanides in molten salt media in relation to the development of Pyrochemical process. The on-line electrochemical/spectroscopic measurement system is to produce electrochemical parameters and thermodynamic parameters of actinides and lanthanides in molten salts by using spectroscopic techniques such as UV-VIS absorption as well as electrochemical in-situ measurement techniques. The on-line electrochemical/spectroscopic measurement system can be applied to understand the chemical reactions and oxidation states of actinides and lanthanides in molten salts eventually for the Pyrochemical process

Book Review: Reiner Salzer and Heinz W. Siesler (Eds.): Infrared and Raman spectroscopic imaging, 2nd ed

International Nuclear Information System (INIS)

Moore, David Steven

2015-01-01

This second edition of 'Infrared and Raman Spectroscopic Imaging' propels practitioners in that wide-ranging field, as well as other readers, to the current state of the art in a well-produced and full-color, completely revised and updated, volume. This new edition chronicles the expanded application of vibrational spectroscopic imaging from yesterday's time-consuming point-by-point buildup of a hyperspectral image cube, through the improvements afforded by the addition of focal plane arrays and line scan imaging, to methods applicable beyond the diffraction limit, instructs the reader on the improved instrumentation and image and data analysis methods, and expounds on their application to fundamental biomedical knowledge, food and agricultural surveys, materials science, process and quality control, and many others

Synthesis, structural characterization, Hirshfeld surface analysis and spectroscopic studies of cadmium (II) chloride complex with 4-hydroxy-1-methylpiperidine

Energy Technology Data Exchange (ETDEWEB)

Soudani, S. [Université de Carthage, Laboratoire de Chimie des Matériaux, Faculté des Sciences de Bizerte, 7021 Zarzouna (Tunisia); Ferretti, V. [Department of Chemical and Pharmaceutical Sciences and Center for Structural Diffractometry, via Fossato di Mortara 17, I-44121 Ferrara (Italy); Jelsch, C. [CRM2, CNRS, Institut Jean Barriol, Université de Lorraine, Vandoeuvre les Nancy CEDEX (France); Lefebvre, F. [Laboratoire de Chimie Organométallique de Surface (LCOMS), Ecole Supérieure de Chimie Physique Electronique, 69626 Villeurbanne Cedex (France); Nasr, C. Ben, E-mail: cherif_bennasr@yahoo.fr [Université de Carthage, Laboratoire de Chimie des Matériaux, Faculté des Sciences de Bizerte, 7021 Zarzouna (Tunisia)

2016-05-15

The chemical preparation, crystal structure, Hirshfeld surface analysis and spectroscopic characterization of the novel cadmium (II) 4-hydroxy-1-methylpiperidine complex, Cd{sub 4}Cl{sub 10}(C{sub 6}H{sub 14}NO){sub 2}·2H{sub 2}O, have been reported. The atomic arrangement can be described as built up by an anionic framework, formed by edge sharing CdCl{sub 6} and CdCl{sub 5}O octahedral linear chains spreading along the a-axis. These chains are interconnected by water molecules via O–H⋯Cl and O–H⋯O hydrogen bonds to form layers parallel to (011) plane. The organic cations are inserted between layers through C–H⋯Cl hydrogen bonds. Investigation of intermolecular interactions and crystal packing via Hirshfeld surface analysis reveals that the H{sub C}⋯Cl and H{sub C}⋯H{sub C} intermolecular interactions are the most abundant contacts of the organic cation in the crystal packing. The statistical analysis of crystal contacts reveals the driving forces in the packing formation. The {sup 13}C and {sup 15}N CP-MAS NMR spectra are in agreement with the X-ray structure. The vibrational absorption bands were identified by infrared spectroscopy. DFT calculations allowed the attribution of the NMR peaks and of the IR bands.

Raman spectroscopic biochemical mapping of tissues

Science.gov (United States)

Stone, Nicholas; Hart Prieto, Maria C.; Kendall, Catherine A.; Shetty, Geeta; Barr, Hugh

2006-02-01

Advances in technologies have brought us closer to routine spectroscopic diagnosis of early malignant disease. However, there is still a poor understanding of the carcinogenesis process. For example it is not known whether many cancers follow a logical sequence from dysplasia, to carcinoma in situ, to invasion. Biochemical tissue changes, triggered by genetic mutations, precede morphological and structural changes. These can be probed using Raman or FTIR microspectroscopy and the spectra analysed for biochemical constituents. Local microscopic distribution of various constituents can then be visualised. Raman mapping has been performed on a number of tissues including oesophagus, breast, bladder and prostate. The biochemical constituents have been calculated at each point using basis spectra and least squares analysis. The residual of the least squares fit indicates any unfit spectral components. The biochemical distribution will be compared with the defined histopathological boundaries. The distribution of nucleic acids, glycogen, actin, collagen I, III, IV, lipids and others appear to follow expected patterns.

The HITRAN2016 molecular spectroscopic database

Energy Technology Data Exchange (ETDEWEB)

Gordon, I. E.; Rothman, L. S.; Hill, C.; Kochanov, R. V.; Tan, Y.; Bernath, P. F.; Birk, M.; Boudon, V.; Campargue, A.; Chance, K. V.; Drouin, B. J.; Flaud, J. -M.; Gamache, R. R.; Hodges, J. T.; Jacquemart, D.; Perevalov, V. I.; Perrin, A.; Shine, K. P.; Smith, M. -A. H.; Tennyson, J.; Toon, G. C.; Tran, H.; Tyuterev, V. G.; Barbe, A.; Császár, A. G.; Devi, V. M.; Furtenbacher, T.; Harrison, J. J.; Hartmann, J. -M.; Jolly, A.; Johnson, T. J.; Karman, T.; Kleiner, I.; Kyuberis, A. A.; Loos, J.; Lyulin, O. M.; Massie, S. T.; Mikhailenko, S. N.; Moazzen-Ahmadi, N.; Müller, H. S. P.; Naumenko, O. V.; Nikitin, A. V.; Polyansky, O. L.; Rey, M.; Rotger, M.; Sharpe, S. W.; Sung, K.; Starikova, E.; Tashkun, S. A.; Auwera, J. Vander; Wagner, G.; Wilzewski, J.; Wcisło, P.; Yu, S.; Zak, E. J.

2017-12-01

This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is comprised of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 200 additional significant molecules have been added to the database.

Theoretical studies on CH+ ion molecule using configuration interaction method and its spectroscopic properties

International Nuclear Information System (INIS)

Machado, F.B.C.

1985-01-01

The use of the configuration (CI) method for the calculation of very accurate potential energy curves and dipole moment functions, and then their use in the comprehension of spectroscopic properties of diatomic molecules is presented. The spectroscopic properties of CH + and CD + such as: vibrational levels, spectroscopic constants, averaged dipole moments for all vibrational levels, radiative transition probabilities for emission and absorption, and radiative lifetimes are verificated. (M.J.C.) [pt

IMPROVED SPECTROSCOPIC PARAMETERS FOR TRANSITING PLANET HOSTS

Energy Technology Data Exchange (ETDEWEB)

Torres, Guillermo; Holman, Matthew J.; Carter, Joshua A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Fischer, Debra A. [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Sozzetti, Alessandro [INAF-Osservatorio Astronomico di Torino, I-10025 Pino Torinese (Italy); Buchhave, Lars A. [Niels Bohr Institute, Copenhagen University, DK-2100 Copenhagen (Denmark); Winn, Joshua N., E-mail: gtorres@cfa.harvard.edu [Department of Physics, and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

2012-10-01

We report homogeneous spectroscopic determinations of the effective temperature, metallicity, and projected rotational velocity for the host stars of 56 transiting planets. Our analysis is based primarily on the stellar parameter classification (SPC) technique. We investigate systematic errors by examining subsets of the data with two other methods that have often been used in previous studies (Spectroscopy Made Easy (SME) and MOOG). The SPC and SME results, both based on comparisons between synthetic spectra and actual spectra, show strong correlations between T{sub eff}, [Fe/H], and log g when solving for all three quantities simultaneously. In contrast the MOOG results, based on a more traditional curve-of-growth approach, show no such correlations. To combat the correlations and improve the accuracy of the temperatures and metallicities, we repeat the SPC analysis with a constraint on log g based on the mean stellar density that can be derived from the analysis of the transit light curves. Previous studies that have not taken advantage of this constraint have been subject to systematic errors in the stellar masses and radii of up to 20% and 10%, respectively, which can be larger than other observational uncertainties, and which also cause systematic errors in the planetary mass and radius.

Synthesis and IR spectroscopic investigation of solvated complexes of dioxomolybdenum (6) with salicylal-S-methyl isothiosemicarbazone

International Nuclear Information System (INIS)

Abramenko, V.L.; Sergienko, V.S.

1996-01-01

The complex of MoO 2 L (H 2 L-S-methylizothiosemicarbazone of salicyl aldehyde) and its seven solvated derivatives MoO 2 LxSolv, have been synthesized, their IR spectroscopic study being conducted. The conclusions on the structure of the complexes studied are confirmed by ata of x-ray diffraction analysis. Refs. 4, tabs. 1

Built-in hyperspectral camera for smartphone in visible, near-infrared and middle-infrared lights region (third report): spectroscopic imaging for broad-area and real-time componential analysis system against local unexpected terrorism and disasters

Science.gov (United States)

Hosono, Satsuki; Kawashima, Natsumi; Wollherr, Dirk; Ishimaru, Ichiro

2016-05-01

The distributed networks for information collection of chemical components with high-mobility objects, such as drones or smartphones, will work effectively for investigations, clarifications and predictions against unexpected local terrorisms and disasters like localized torrential downpours. We proposed and reported the proposed spectroscopic line-imager for smartphones in this conference. In this paper, we will mention the wide-area spectroscopic-image construction by estimating 6 DOF (Degrees Of Freedom: parallel movements=x,y,z and rotational movements=θx, θy, θz) from line data to observe and analyze surrounding chemical-environments. Recently, smartphone movies, what were photographed by peoples happened to be there, had worked effectively to analyze what kinds of phenomenon had happened around there. But when a gas tank suddenly blew up, we did not recognize from visible-light RGB-color cameras what kinds of chemical gas components were polluting surrounding atmospheres. Conventionally Fourier spectroscopy had been well known as chemical components analysis in laboratory usages. But volatile gases should be analyzed promptly at accident sites. And because the humidity absorption in near and middle infrared lights has very high sensitivity, we will be able to detect humidity in the sky from wide field spectroscopic image. And also recently, 6-DOF sensors are easily utilized for estimation of position and attitude for UAV (Unmanned Air Vehicle) or smartphone. But for observing long-distance views, accuracies of angle measurements were not sufficient to merge line data because of leverage theory. Thus, by searching corresponding pixels between line spectroscopic images, we are trying to estimate 6-DOF in high accuracy.

Full spectrum analysis in environmental monitoring

International Nuclear Information System (INIS)

Reinhardt, Sascha; Hartmann, Soeren; Pimpl, Richard

2015-01-01

In the environmental monitoring spectroscopic gamma detectors are frequently used. The motivation to use spectroscopic gamma detectors is the higher sensitivity and specific spectral information. For the analysis often the photo peaks of the gamma spectrum are used to identify the nuclide. These methods are very reliable, robust and well developed but using only the photo peak means also to use only a fraction of the available information. Doing a full spectrum analysis based on principle components obtained from NASVD for description of the radiation background and adjustment calculations are a possible analysis method which may provide advantages compared to a peak based analysis when used for a continuous environmental monitoring. An analysis example is shown and discussed with a measured time series of gamma spectra obtained from a spectroscopic gamma detector SARA IGS710 with a NaI(Tl) scintillator as it is used in the environmental monitoring.

Full spectrum analysis in environmental monitoring

International Nuclear Information System (INIS)

Reinahrdt, S.; Hartmann, S.; Pimpl, R.

2014-01-01

In the environmental monitoring spectroscopic gamma detectors are frequently used. The motivation to use spectroscopic gamma detectors is the higher sensitivity and specific spectral information. For the analysis often the photo peaks of the gamma spectrum are used to identify the nuclide. These methods are very reliable, robust and well developed but using only the photo peak means also to use only a fraction of the available information. Doing a full spectrum analysis based on principal components obtained from NASVD for description of the radiation background and adjustment calculations are a possible analysis method, which may provide advantages compared to a peak based analysis when used for a continuous environmental monitoring. An analysis example is shown and discussed with a measured time series of gamma spectra obtained from a spectroscopic gamma detector SARA IGS710 with a NaI(Tl) scintillator as it is used in the environmental monitoring. (authors)

The Gaia-ESO Public Spectroscopic Survey

DEFF Research Database (Denmark)

Gilmore, G.; Randich, S.; Asplund, M.

2012-01-01

The Gaia-ESO Public Spectroscopic Survey has begun and will obtain high quality spectroscopy of some 100000 Milky Way stars, in the field and in open clusters, down to magnitude 19, systematically covering all the major components of the Milky Way. This survey will provide the first homogeneous o...

Highlights of the Brazilian Solar Spectroscope

Czech Academy of Sciences Publication Activity Database

Sawant, H. S.; Cecatto, J.R.; Mészárosová, Hana; Faria, C.; Fernandes, F. C. R.; Karlický, Marian; de Andrade, M. C.

2009-01-01

Roč. 44, č. 1 (2009), s. 54-57 ISSN 0273-1177 R&D Projects: GA AV ČR IAA300030701 Institutional research plan: CEZ:AV0Z10030501 Keywords : Sun istrumentation * spectroscope * corona * radio radiation Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 1.079, year: 2009

Detection of prostate cancer with MR spectroscopic imaging: an expanded paradigm incorporating polyamines

Energy Technology Data Exchange (ETDEWEB)

Shukla-Dave, A.; Hricak, H.; Moskowitz, C.; Ishill, N.; Akin, O.; Kuroiwa, K.; Spector, J.; Kumar, M.; Reuter, V.E.; Koutcher, J.A.; Zakian, K.L. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States). Dept. of Medical Physics

2007-11-15

Purpose: To characterize benign and malignant prostate peripheral zone (PZ) tissue retrospectively by using a commercial magnetic resonance (MR) spectroscopic imaging package and incorporating the choline plus creatine-to-citrate ratio ([Cho + Cr]/Cit) and polyamine (PA) information into a statistically based voxel classification procedure. Materials and methods: The institutional review board approved this HIPAA-compliant study and waived the requirement for informed consent. Fifty men (median age, 60 years; range, 44-69 years) with untreated biopsy-proved prostate cancer underwent combined endorectal MR imaging and MR spectroscopic imaging. Commercial software was used to acquire and process MR spectroscopic imaging data. The (Cho + Cr)/Cit and the PA level were tabulated for each voxel. The PA level was scored on a scale of 0 (PA undetectable) to 2 (PA peak as high as or higher than Cho peak). Whole-mount step-section histopathologic analysis constituted the reference standard. Classification and regression tree analysis in a training set generated a decision-making tree (rule) for classifying voxels as malignant or benign, which was validated in a test set. Receiver operating characteristic and generalized estimating equation regression analyses were used to assess accuracy and sensitivity, respectively. Results: The median (Cho + Cr)/Cit was 0.55 (mean {+-} standard deviation, 0.59 {+-} 0.03) in benign and 0.77 (mean, 1.08 {+-} 0.20) in malignant PZ voxels (P = .027). A significantly higher percentage of benign (compared with malignant) voxels had higher PA than choline peaks (P < .001). In the 24-patient training set (584 voxels), the rule yielded 54% sensitivity and 91% specificity for cancer detection; in the 26-patient test set (667 voxels), it yielded 42% sensitivity and 85% specificity. The percentage of cancer in the voxel at histopathologic analysis correlated positively (P < .001) with the sensitivity of the classification and regression tree rule

Spectroscopic characterization of Venus at the single molecule level.

Science.gov (United States)

David, Charlotte C; Dedecker, Peter; De Cremer, Gert; Verstraeten, Natalie; Kint, Cyrielle; Michiels, Jan; Hofkens, Johan

2012-02-01

Venus is a recently developed, fast maturating, yellow fluorescent protein that has been used as a probe for in vivo applications. In the present work the photophysical characteristics of Venus were analyzed spectroscopically at the bulk and single molecule level. Through time-resolved single molecule measurements we found that single molecules of Venus display pronounced fluctuations in fluorescence emission, with clear fluorescence on- and off-times. These fluorescence intermittencies were found to occupy a broad range of time scales, ranging from milliseconds to several seconds. Such long off-times can complicate the analysis of single molecule counting experiments or single-molecule FRET experiments. This journal is © The Royal Society of Chemistry and Owner Societies 2012

Design and realisation of a microprogramme for the analysis of nuclear spectroscopic data on the intelligent terminal, H.P.2648A

International Nuclear Information System (INIS)

Tendeku, F.K.

1980-01-01

A microprogramme has been developed for the analysis of nuclear spectroscopic data on the microprocessor-controlled terminal, H.P. 2648A. The terminal enables data to be processed locally. Many operations normally requiring connection to a computer can be performed on a stand alone basis. The principal aspects of the microprogramme are the graphical display of spectral data, the automatic and manual extraction of peaks, and the determination of peak characteristics. Among the features of the microprogramme are algorithms which enable a rapid graphical display of data in logarithmic and linear scales and in divers modes as well as functions enabling image amplification. The automatic peak searching algorithm represents a modified form of the Mariscotti method. The peak analysis procedure offers two options. The first makes use of the data directly. The second is based on the determination of the parameters of the gaussian function which best fits the data points, using the non-linear least squares principle. The terminal has been successfully interfaced to an IBM 370 computer through a satellite computer using the Parallel Duplex Register module of Hewlett Packard [fr

Fuel cells: spectroscopic studies in the electrocatalysis of alcohol oxidation

OpenAIRE

Iwasita Teresa

2002-01-01

Modern spectroscopic methods are useful for elucidating complex electrochemical mechanisms as those occurring during the oxidation of small organic molecules (CH3OH, HCOH, HCOOH). In the present paper it is shown the use of spectroscopic methods to study the oxidation of alcohols on platinum or Pt-based binary electrodes. These reactions are of importance in conexion with the development of anode systems for use in fuel cells. Mass spectrometry and FT infrared spectroscopy allow to establishi...

Identification and Spectroscopic Characterization of Nonheme Iron(III) Hypochlorite Intermediates**

Science.gov (United States)

Draksharapu, Apparao; Angelone, Davide; Quesne, Matthew G; Padamati, Sandeep K; Gómez, Laura; Hage, Ronald; Costas, Miquel; Browne, Wesley R; de Visser, Sam P

2015-01-01

FeIII–hypohalite complexes have been implicated in a wide range of important enzyme-catalyzed halogenation reactions including the biosynthesis of natural products and antibiotics and post-translational modification of proteins. The absence of spectroscopic data on such species precludes their identification. Herein, we report the generation and spectroscopic characterization of nonheme FeIII–hypohalite intermediates of possible relevance to iron halogenases. We show that FeIII-OCl polypyridylamine complexes can be sufficiently stable at room temperature to be characterized by UV/Vis absorption, resonance Raman and EPR spectroscopies, and cryo-ESIMS. DFT methods rationalize the pathways to the formation of the FeIII-OCl, and ultimately FeIV=O, species and provide indirect evidence for a short-lived FeII-OCl intermediate. The species observed and the pathways involved offer insight into and, importantly, a spectroscopic database for the investigation of iron halogenases. PMID:25663379

Polarized spectroscopic properties of Nd3+-doped KGd(WO4)2 single crystal

International Nuclear Information System (INIS)

Chen Yujin; Lin Yanfu; Gong Xinghong; Tan Qiguang; Zhuang Jian; Luo Zundu; Huang Yidong

2007-01-01

The polarized absorption spectra, infrared fluorescence spectra, upconversion visible fluorescence spectra, and fluorescence decay curve of orientated Nd 3+ :KGd(WO 4 ) 2 crystal were measured at room-temperature. Some important spectroscopic parameters were investigated in detail in the framework of the Judd-Ofelt theory and the Fuchtbauer-Ladenburg formula. The effect of the crystal structure on the spectroscopic properties of the Nd 3+ ions was analyzed. The relation among the spectroscopic parameters and the laser performances of the Nd 3+ :KGd(WO 4 ) 2 crystal was discussed

Growth, structure, Hirshfeld surface and spectroscopic properties of 2-amino-4-hydroxy-6-methylpyrimidinium-2,3-pyrazinedicorboxylate single crystal

Science.gov (United States)

Faizan, Mohd; Alam, Mohammad Jane; Afroz, Ziya; Rodrigues, Vítor Hugo Nunes; Ahmad, Shabbir

2018-03-01

The present work is focused on the crystal structure, vibrational spectroscopy and DFT calculations of hydrogen bonded 2,3-pyrazinedicorboxylic acid and 2-amino-4-hydroxy-6-methylpyrimidine (PDCA-.AHMP+) crystal. The crystal structure has been determined using single crystal X-ray diffraction analysis which shows that the crystal belongs to monoclinic space group P21/n. The PDCA-.AHMP+ crystal has been characterized by FTIR, FT-Raman and FT-NMR spectroscopic techniques. The FTIR and FT-Raman spectra of the complex have unique spectroscopic feature as compared with those of the starting material to confirm salt formation. The theoretical vibrational studies have been performed to understand the modes of the vibrations of asymmetric unit of the complex by DFT methods. Hirschfeld surface and 2D fingerprint plots analyses were carried out to investigate the intermolecular interactions and its contribution in the building of PDCA-.AHMP+ crystal. The experimental and simulated 13C and 1H NMR studies have assisted in structural analysis of PDCA-.AHMP+ crystal. The electronic spectroscopic properties of the complex were explored by the experimental as well as theoretical electronic spectra simulated using TD-DFT/IEF-PCM method at B3LYP/6-311++G (d,p) level of theory. In addition, frontier molecular orbitals, molecular electrostatic potential map (MEP) and nonlinear optical (NLO) properties using DFT method have been also presented.

The VANDELS ESO public spectroscopic survey

Science.gov (United States)

McLure, R. J.; Pentericci, L.; Cimatti, A.; Dunlop, J. S.; Elbaz, D.; Fontana, A.; Nandra, K.; Amorin, R.; Bolzonella, M.; Bongiorno, A.; Carnall, A. C.; Castellano, M.; Cirasuolo, M.; Cucciati, O.; Cullen, F.; De Barros, S.; Finkelstein, S. L.; Fontanot, F.; Franzetti, P.; Fumana, M.; Gargiulo, A.; Garilli, B.; Guaita, L.; Hartley, W. G.; Iovino, A.; Jarvis, M. J.; Juneau, S.; Karman, W.; Maccagni, D.; Marchi, F.; Mármol-Queraltó, E.; Pompei, E.; Pozzetti, L.; Scodeggio, M.; Sommariva, V.; Talia, M.; Almaini, O.; Balestra, I.; Bardelli, S.; Bell, E. F.; Bourne, N.; Bowler, R. A. A.; Brusa, M.; Buitrago, F.; Caputi, K. I.; Cassata, P.; Charlot, S.; Citro, A.; Cresci, G.; Cristiani, S.; Curtis-Lake, E.; Dickinson, M.; Fazio, G. G.; Ferguson, H. C.; Fiore, F.; Franco, M.; Fynbo, J. P. U.; Galametz, A.; Georgakakis, A.; Giavalisco, M.; Grazian, A.; Hathi, N. P.; Jung, I.; Kim, S.; Koekemoer, A. M.; Khusanova, Y.; Fèvre, O. Le; Lotz, J. M.; Mannucci, F.; Maltby, D. T.; Matsuoka, K.; McLeod, D. J.; Mendez-Hernandez, H.; Mendez-Abreu, J.; Mignoli, M.; Moresco, M.; Mortlock, A.; Nonino, M.; Pannella, M.; Papovich, C.; Popesso, P.; Rosario, D. P.; Salvato, M.; Santini, P.; Schaerer, D.; Schreiber, C.; Stark, D. P.; Tasca, L. A. M.; Thomas, R.; Treu, T.; Vanzella, E.; Wild, V.; Williams, C. C.; Zamorani, G.; Zucca, E.

2018-05-01

VANDELS is a uniquely-deep spectroscopic survey of high-redshift galaxies with the VIMOS spectrograph on ESO's Very Large Telescope (VLT). The survey has obtained ultra-deep optical (0.48 studies. Using integration times calculated to produce an approximately constant signal-to-noise ratio (20 motivation, survey design and target selection.

Nanosecond and femtosecond mass spectroscopic analysis of a molecular beam produced by the spray-jet technique

International Nuclear Information System (INIS)

Yamada, Toshiki; Shinohara, Hidenori; Kamikado, Toshiya; Okuno, Yoshishige; Suzuki, Hitoshi; Mashiko, Shinro; Yokoyama, Shiyoshi

2008-01-01

The spray-jet molecular beam apparatus enabled us to produce a molecular beam of non-volatile molecules under high vacuum from a sprayed mist of sample solutions. The apparatus has been used in spectroscopic studies and as a means of molecular beam deposition. We analyzed the molecular beam, consisting of non-volatile, solvent, and carrier-gas molecules, by using femtosecond- and nanosecond- laser mass spectroscopy. The information thus obtained provided insight into the molecular beam produced by the spray-jet technique

7th Czechoslovak spectroscopic conference and VIIIth CANAS (Conference on analytical atomic spectroscopy). Abstracts. Vol. 2

International Nuclear Information System (INIS)

1984-01-01

The conference on spectroscopy held in Ceske Budejovice on June 18-22, 1984, proceeded in three sessions: atomic spectroscopy, molecular spectroscopy and special spectroscopic techniques. In the molecular spectroscopy session, 81 papers were read of which 12 were inputted in INIS. The subject of inputted papers was the use of NMR for the analysis of organic compounds and for the study of radiation defects in semiconductors, and the use of infrared spectroscopy for the analysis of nuclear and irradiated materials. (J.P.)

Spectroscopic diagnostics of plasma during laser processing of aluminium

International Nuclear Information System (INIS)

Lober, R; Mazumder, J

2007-01-01

The role of the plasma in laser-metal interaction is of considerable interest due to its influence in the energy transfer mechanism in industrial laser materials processing. A 10 kW CO 2 laser was used to study its interaction with aluminium under an argon environment. The objective was to determine the absorption and refraction of the laser beam through the plasma during the processing of aluminium. Laser processing of aluminium is becoming an important topic for many industries, including the automobile industry. The spectroscopic relative line to continuum method was used to determine the electron temperature distribution within the plasma by investigating the 4158 A Ar I line emission and the continuum adjacent to it. The plasmas are induced in 1.0 atm pure Ar environment over a translating Al target, using f/7 and 10 kW CO 2 laser. Spectroscopic data indicated that the plasma composition and behaviour were Ar-dominated. Experimental results indicated the plasma core temperature to be 14 000-15 300 K over the incident range of laser powers investigated from 5 to 7 kW. It was found that 7.5-29% of the incident laser power was absorbed by the plasma. Cross-section analysis of the melt pools from the Al samples revealed the absence of any key-hole formation and confirmed that the energy transfer mechanism in the targets was conduction dominated for the reported range of experimental data

Spectroscopic diagnostics of plasma during laser processing of aluminium

Science.gov (United States)

Lober, R.; Mazumder, J.

2007-10-01

The role of the plasma in laser-metal interaction is of considerable interest due to its influence in the energy transfer mechanism in industrial laser materials processing. A 10 kW CO2 laser was used to study its interaction with aluminium under an argon environment. The objective was to determine the absorption and refraction of the laser beam through the plasma during the processing of aluminium. Laser processing of aluminium is becoming an important topic for many industries, including the automobile industry. The spectroscopic relative line to continuum method was used to determine the electron temperature distribution within the plasma by investigating the 4158 Å Ar I line emission and the continuum adjacent to it. The plasmas are induced in 1.0 atm pure Ar environment over a translating Al target, using f/7 and 10 kW CO2 laser. Spectroscopic data indicated that the plasma composition and behaviour were Ar-dominated. Experimental results indicated the plasma core temperature to be 14 000-15 300 K over the incident range of laser powers investigated from 5 to 7 kW. It was found that 7.5-29% of the incident laser power was absorbed by the plasma. Cross-section analysis of the melt pools from the Al samples revealed the absence of any key-hole formation and confirmed that the energy transfer mechanism in the targets was conduction dominated for the reported range of experimental data.

The effect of synthesis temperature on the formation of hydrotalcites in Bayer liquor: a vibrational spectroscopic analysis.

Science.gov (United States)

Palmer, Sara J; Frost, Ray L

2009-07-01

The seawater neutralization process is currently used in the alumina industry to reduce the pH and dissolved metal concentrations in bauxite refinery residues through the precipitation of Mg, Al, and Ca hydroxide and carbonate minerals. This neutralization method is very similar to the co-precipitation method used to synthesize hydrotalcite (Mg6Al2(OH)16CO3.4H2O). This study looks at the effect of temperature on the type of precipitates that form from the seawater neutralization process of Bayer liquor. The Bayer precipitates have been characterized by a variety of techniques, including X-ray diffraction (XRD), Raman spectroscopy, and infrared spectroscopy. The mineralogical composition of Bayer precipitates largely includes hydrotalcite, hydromagnesite, and calcium carbonate species. Analysis with XRD determined that Bayer hydrotalcites that are synthesized at 55 degrees C have a larger interlayer distance, indicating that more anions are removed from Bayer liquor. Vibrational spectroscopic techniques have identified an increase in hydrogen bond strength for precipitates formed at 55 degrees C, suggesting the formation of a more stable Bayer hydrotalcite. Raman spectroscopy identified the intercalation of sulfate and carbonate anions into Bayer hydrotalcites using these synthesis conditions.

Near-Infrared Spectroscopic Method for Monitoring Water Content in Epoxy Resins and Fiber-Reinforced Composites

Directory of Open Access Journals (Sweden)

Andrey E. Krauklis

2018-04-01

Full Text Available Monitoring water content and predicting the water-induced drop in strength of fiber-reinforced composites are of great importance for the oil and gas and marine industries. Fourier transform infrared (FTIR spectroscopic methods are broadly available and often used for process and quality control in industrial applications. A benefit of using such spectroscopic methods over the conventional gravimetric analysis is the possibility to deduce the mass of an absolutely dry material and subsequently the true water content, which is an important indicator of water content-dependent properties. The objective of this study is to develop an efficient and detailed method for estimating the water content in epoxy resins and fiber-reinforced composites. In this study, Fourier transform near-infrared (FT-NIR spectroscopy was applied to measure the water content of amine-epoxy neat resin. The method was developed and successfully extended to glass fiber-reinforced composite materials. Based on extensive measurements of neat resin and composite samples of varying water content and thickness, regression was performed, and the quantitative absorbance dependence on water content in the material was established. The mass of an absolutely dry resin was identified, and the true water content was obtained. The method was related to the Beer–Lambert law and explained in such terms. A detailed spectroscopic method for measuring water content in resins and fiber-reinforced composites was developed and described.

Near-Infrared Spectroscopic Method for Monitoring Water Content in Epoxy Resins and Fiber-Reinforced Composites.

Science.gov (United States)

Krauklis, Andrey E; Gagani, Abedin I; Echtermeyer, Andreas T

2018-04-11

Monitoring water content and predicting the water-induced drop in strength of fiber-reinforced composites are of great importance for the oil and gas and marine industries. Fourier transform infrared (FTIR) spectroscopic methods are broadly available and often used for process and quality control in industrial applications. A benefit of using such spectroscopic methods over the conventional gravimetric analysis is the possibility to deduce the mass of an absolutely dry material and subsequently the true water content, which is an important indicator of water content-dependent properties. The objective of this study is to develop an efficient and detailed method for estimating the water content in epoxy resins and fiber-reinforced composites. In this study, Fourier transform near-infrared (FT-NIR) spectroscopy was applied to measure the water content of amine-epoxy neat resin. The method was developed and successfully extended to glass fiber-reinforced composite materials. Based on extensive measurements of neat resin and composite samples of varying water content and thickness, regression was performed, and the quantitative absorbance dependence on water content in the material was established. The mass of an absolutely dry resin was identified, and the true water content was obtained. The method was related to the Beer-Lambert law and explained in such terms. A detailed spectroscopic method for measuring water content in resins and fiber-reinforced composites was developed and described.

Experimental and theoretical studies on the structural, spectroscopic and hydrogen bonding on 4-nitro-n-(2,4-dinitrophenyl) benzenamine

Science.gov (United States)

Subhapriya, G.; Kalyanaraman, S.; Jeyachandran, M.; Ragavendran, V.; Krishnakumar, V.

2018-04-01

Synthesized 4-nitro-N-(2,4-dinitrophenyl) benzenamine (NDPBA) molecule was confirmed applying the tool of NMR. Theoretical prediction addressed the NMR chemical shifts and correlated well with the experimental data. The molecule subjected to theoretical DFT at 6-311++G** level unraveled the spectroscopic and structural properties of the NDPBA molecule. Moreover the structural features proved the occurrence of intramolecular Nsbnd H· · O hydrogen bonding in the molecule which was further confirmed with the help of Frontier molecular orbital analysis. Vibrational spectroscopic characterization through FT-IR and Raman experimentally and theoretically gave an account for the vibrational properties. An illustration of the topology of the molecule theoretically helped also in finding the hydrogen bonding energy.

Multivariate curve resolution applied to kinetic-spectroscopic data matrices: Dye determination in foods by means of enzymatic oxidation.

Science.gov (United States)

Boeris, Valeria; Arancibia, Juan A; Olivieri, Alejandro C

2017-07-01

In this work, the combination of chemometric techniques with kinetic-spectroscopic data allowed quantifying two dyes (tartrazine and carminic acid) in complex matrices as mustard, ketchup, asparagus soup powder, pumpkin soup powder, plum jam and orange-strawberry juice. Quantitative analysis was performed without the use of tedious sample pretreatment, due to the achievement of the second-order advantage. The results obtained showed an improvement in simplicity, speed and cost with respect to usual separation techniques, allowing to properly quantifying these dyes obtaining limits of detection below 0.6mgL -1 . In addition, to the best of our knowledge, is the first time that kinetic-spectroscopic data are obtained from the action of laccase for analytical purposes. Copyright © 2017 Elsevier B.V. All rights reserved.

How spectroscopic x-ray imaging benefits from inter-pixel communication

CERN Document Server

Koenig, Thomas; Hamann, Elias; Cecilia, Angelica; Ballabriga, Rafael; Campbell, Michael; Ruat, Marie; Tlustos, Lukas; Fauler, Alex; Fiederle, Michael; Baumbach, Tilo

2014-01-01

Spectroscopic x-ray imaging based on pixellated semiconductor detectors can be sensitive to charge sharing and K-fluorescence, depending on the sensor material used, its thickness and the pixel pitch employed. As a consequence, spectroscopic resolution is partially lost. In this paper, we study a new detector ASIC, the Medipix3RX, that offers a novel feature called charge summing, which is established by making adjacent pixels communicate with each other. Consequently, single photon interactions resulting in multiple hits are almost completely avoided. We investigate this charge summing mode with respect to those of its imaging properties that are of interest in medical physics and benchmark them against the case without charge summing. In particular, we review its influence on spectroscopic resolution and find that the low energy bias normally present when recording energy spectra is dramatically reduced. Furthermore, we show that charge summing provides a modulation transfer function which is almost indepen...

A rapid method of radium-226 analysis in water samples using an alpha spectroscopic technique

International Nuclear Information System (INIS)

Lim, T.P.

1981-01-01

A fast, reliable and accurate method for radium-226 determination in environmental water samples has been devised, using an alpha spectroscopic technique. The correlation between barium-133 and radium-226 in the barium-radium sulphate precipitation mechanism was studied and in the limited experimental recovery range, the coefficient of correlation was r = 0.986. A self-absorption study for various barium carrier concentrations was also undertaken to obtain the least broadening of alpha energy line widths. An optimum value of 0.3 mg barium carrier was obtained for chemical recovery in the range of 85 percent. (auth)

Soil sample moisture content as a function of time during oven drying for gamma-ray spectroscopic measurements

International Nuclear Information System (INIS)

Benke, R.R.; Kearfott, K.J.

1999-01-01

In routine gamma-ray spectroscopic analysis of collected soil samples, procedure often calls to remove soil moisture by oven drying overnight at a temperature of 100 deg. C . Oven drying not only minimizes the gamma-ray self-attenuation of soil samples due to the absence of water during the gamma-ray spectroscopic analysis, but also allows for a straightforward calculation of the specific activity of radionuclides in soil, historically based on the sample dry weight. Because radon exhalation is strongly dependent on moisture , knowledge of the oven-drying time dependence of the soil moisture content, combined with radon exhalation measurements during oven drying and at room temperature for varying soil moisture contents, would allow conclusions to be made on how the oven-drying radon exhalation rate depends on soil moisture content. Determinations of the oven-drying radon exhalation from soil samples allow corrections to be made for the immediate laboratory gamma-ray spectroscopy of radionuclides in the natural uranium decay chain. This paper presents the results of soil moisture content measurements during oven drying and suggests useful empirical fits to the moisture data

Spectroscopic characterization of alkaline earth uranyl carbonates

International Nuclear Information System (INIS)

Amayri, Samer; Reich, Tobias; Arnold, Thuro; Geipel, Gerhard; Bernhard, Gert

2005-01-01

A series of alkaline uranyl carbonates, M[UO 2 (CO 3 ) 3 ].nH 2 O (M=Mg 2 , Ca 2 , Sr 2 , Ba 2 , Na 2 Ca, and CaMg) was synthesized and characterized by inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS) after nitric acid digestion, X-ray powder diffraction (XRD), and thermal analysis (TGA/DTA). The molecular structure of these compounds was characterized by extended X-ray absorption fine-structure (EXAFS) spectroscopy and X-ray photoelectron spectroscopy (XPS). Crystalline Ba 2 [UO 2 (CO 3 ) 3 ].6H 2 O was obtained for the first time. The EXAFS analysis showed that this compound consists of (UO 2 )(CO 3 ) 3 clusters similar to the other alkaline earth uranyl carbonates. The average U-Ba distance is 3.90+/-0.02A.Fluorescence wavelengths and life times were measured using time-resolved laser-induced fluorescence spectroscopy (TRLFS). The U-O bond distances determined by EXAFS, TRLFS, XPS, and Raman spectroscopy agree within the experimental uncertainties. The spectroscopic signatures observed could be useful for identifying uranyl carbonate species adsorbed on mineral surfaces

Single nanoparticle tracking spectroscopic microscope

Science.gov (United States)

Yang, Haw [Moraga, CA; Cang, Hu [Berkeley, CA; Xu, Cangshan [Berkeley, CA; Wong, Chung M [San Gabriel, CA

2011-07-19

A system that can maintain and track the position of a single nanoparticle in three dimensions for a prolonged period has been disclosed. The system allows for continuously imaging the particle to observe any interactions it may have. The system also enables the acquisition of real-time sequential spectroscopic information from the particle. The apparatus holds great promise in performing single molecule spectroscopy and imaging on a non-stationary target.

Are your Spectroscopic Data Being Used?

Science.gov (United States)

Gordon, Iouli E.; Rothman, Laurence S.; Wilzewski, Jonas

2014-06-01

Spectroscopy is an established and indispensable tool in science, industry, agriculture, medicine, surveillance, etc.. The potential user of spectral data, which is not available in HITRAN or other databases, searches the spectroscopy publications. After finding the desired publication, the user very often encounters the following problems: 1) They cannot find the data described in the paper. There can be many reasons for this: nothing is provided in the paper itself or supplementary material; the authors are not responding to any requests; the web links provided in the paper have long been broken; etc. 2) The data is presented in a reduced form, for instance through the fitted spectroscopic constants. While this is a long-standing practice among spectroscopists, there are numerous serious problems with this practice, such as users getting different energy and intensity values because of different representations of the solution to the Hamiltonian, or even just despairing of trying to generate usable line lists from the published constants. Properly providing the data benefits not only users but also the authors of the spectroscopic research. We will show that this increases citations to the spectroscopy papers and visibility of the research groups. We will also address the quite common issue when researchers obtain the data, but do not feel that they have time, interest or resources to write an article describing it. There are modern tools that would allow one to make these data available to potential users and still get credit for it. However, this is a worst case scenario recommendation, i.e., publishing the data in a peer-reviewed journal is still the preferred way. L. S. Rothman, I. E. Gordon, et al. "The HITRAN 2012 molecular spectroscopic database," JQSRT 113, 4-50 (2013).

New Insight into the Observation of Spectroscopic Strength Reduction in Atomic Nuclei: Implication for the Physical Meaning of Spectroscopic Factors

International Nuclear Information System (INIS)

Timofeyuk, N. K.

2009-01-01

Experimental studies of one-nucleon knockout from magic nuclei suggest that their nucleon orbits are not fully occupied. This conflicts a commonly accepted view of the shell closure associated with such nuclei. The conflict can be reconciled if the overlap between initial and final nuclear states in a knockout reaction are calculated by a nonstandard method. The method employs an inhomogeneous equation based on correlation-dependent effective nucleon-nucleon interactions and allows the simplest wave functions, in which all nucleons occupy only the lowest nuclear orbits, to be used. The method also reproduces the recently established relation between reduction of spectroscopic strength, observed in knockout reactions on other nuclei, and nucleon binding energies. The implication of the inhomogeneous equation method for the physical meaning of spectroscopic factors is discussed.

Automated reliability assessment for spectroscopic redshift measurements

Science.gov (United States)

Jamal, S.; Le Brun, V.; Le Fèvre, O.; Vibert, D.; Schmitt, A.; Surace, C.; Copin, Y.; Garilli, B.; Moresco, M.; Pozzetti, L.

2018-03-01

Context. Future large-scale surveys, such as the ESA Euclid mission, will produce a large set of galaxy redshifts (≥106) that will require fully automated data-processing pipelines to analyze the data, extract crucial information and ensure that all requirements are met. A fundamental element in these pipelines is to associate to each galaxy redshift measurement a quality, or reliability, estimate. Aim. In this work, we introduce a new approach to automate the spectroscopic redshift reliability assessment based on machine learning (ML) and characteristics of the redshift probability density function. Methods: We propose to rephrase the spectroscopic redshift estimation into a Bayesian framework, in order to incorporate all sources of information and uncertainties related to the redshift estimation process and produce a redshift posterior probability density function (PDF). To automate the assessment of a reliability flag, we exploit key features in the redshift posterior PDF and machine learning algorithms. Results: As a working example, public data from the VIMOS VLT Deep Survey is exploited to present and test this new methodology. We first tried to reproduce the existing reliability flags using supervised classification in order to describe different types of redshift PDFs, but due to the subjective definition of these flags (classification accuracy 58%), we soon opted for a new homogeneous partitioning of the data into distinct clusters via unsupervised classification. After assessing the accuracy of the new clusters via resubstitution and test predictions (classification accuracy 98%), we projected unlabeled data from preliminary mock simulations for the Euclid space mission into this mapping to predict their redshift reliability labels. Conclusions: Through the development of a methodology in which a system can build its own experience to assess the quality of a parameter, we are able to set a preliminary basis of an automated reliability assessment for

Spectroscopic characterizations of organic/inorganic nanocomposites

Science.gov (United States)

Govani, Jayesh R.

2009-12-01

In the present study, pure and 0.3 wt%, 0.4 wt%, as well as 0.5 wt% L-arginine doped potassium dihydrogen phosphate (KDP) crystals were grown using solution growth techniques and further subjected to infrared (IR) absorption and Raman studies for confirmation of chemical group functionalization for investigating the incorporation mechanism of the L-arginine organic material into the KDP crystal structure. Infrared spectroscopic analysis suggests that structural changes are occurring for the L-arginine molecule as a result of its interaction with the KPD crystal. Infrared spectroscopic technique confirms the disturbance of the N-H, C-H and C-N bonds of the amino acid, suggesting successful incorporation of L-arginine into the KDP crystals. Raman analysis also reveals modification of the N-H, C-H and C-N bonds of the amino acid, implying successful inclusion of L-arginine into the KDP crystals. With the help of Gaussian software, a prediction of possible incorporation mechanisms of the organic material was obtained from comparison of the simulated infrared and Raman vibrational spectra with the experimental results. Furthermore, we also studied the effect of L-arginine doping on the thermal stability of the grown KDP crystal by employing Thermo gravimetric analysis (TGA). TGA suggests that increasing the level of L-arginine doping speeds the decomposition process and it weakens the KDP crystal, which indicates successful doping of the KDP crystals with L-arginine amino acid. Urinary stones are one of the oldest and most widely spread diseases in humans, animals and birds. Many remedies have been employed through the ages for the treatment of urinary stones. Recent medicinal measures reflect the modern advances, which are based on surgical removal, percutaneous techniques and extracorporeal shock wave lithotripsy (ESWL). Although these procedures are valuable, they are quite expensive for most people. Furthermore, recurrence of these diseases is awfully frequent with

Spectroscopic follow up of Kepler planet candidates

DEFF Research Database (Denmark)

Latham..[], D. W.; Cochran, W. D.; Marcy, G.W.

2010-01-01

Spectroscopic follow-up observations play a crucial role in the confirmation and characterization of transiting planet candidates identified by Kepler. The most challenging part of this work is the determination of radial velocities with a precision approaching 1 m/s in order to derive masses from...... spectroscopic orbits. The most precious resource for this work is HIRES on Keck I, to be joined by HARPS-North on the William Herschel Telescope when that new spectrometer comes on line in two years. Because a large fraction of the planet candidates are in fact stellar systems involving eclipsing stars...... and not planets, our strategy is to start with reconnaissance spectroscopy using smaller telescopes, to sort out and reject as many of the false positives as possible before going to Keck. During the first Kepler observing season in 2009, more than 100 nights of telescope time were allocated for this work, using...

Raman spectroscopic study of "The Malatesta": a Renaissance painting?

Science.gov (United States)

Edwards, Howell G M; Vandenabeele, Peter; Benoy, Timothy J

2015-02-25

Raman spectroscopic analysis of the pigments on an Italian painting described as a "Full Length Portrait of a Gentleman", known also as the "Malatesta", and attributed to the Renaissance period has established that these are consistent with the historical research provenance undertaken earlier. Evidence is found for the early 19th Century addition of chrome yellow to highlighted yellow ochre areas in comparison with a similar painting executed in 1801 by Sir Thomas Lawrence of John Kemble in the role of Hamlet, Prince of Denmark. The Raman data are novel in that no analytical studies have previously been made on this painting and reinforces the procedure whereby scientific analyses are accompanied by parallel historical research. Copyright © 2014 Elsevier B.V. All rights reserved.

A NEAR-INFRARED SPECTROSCOPIC SURVEY OF COOL WHITE DWARFS IN THE SLOAN DIGITAL SKY SURVEY

International Nuclear Information System (INIS)

Kilic, Mukremin; Kowalski, Piotr M.; Von Hippel, Ted

2009-01-01

We present near-infrared photometric observations of 15 and spectroscopic observations of 38 cool white dwarfs (WDs). This is the largest near-infrared spectroscopic survey of cool WDs to date. Combining the Sloan Digital Sky Survey photometry and our near-infrared data, we perform a detailed model atmosphere analysis. The spectral energy distributions of our objects are explained fairly well by model atmospheres with temperatures ranging from 6300 K down to 4200 K. Two WDs show significant absorption in the infrared, and are best explained with mixed H/He atmosphere models. Based on the up-to-date model atmosphere calculations by Kowalski and Saumon, we find that the majority of the stars in our sample have hydrogen-rich atmospheres. We do not find any pure helium atmosphere WDs below 5000 K, and we find a trend of increasing hydrogen to helium ratio with decreasing temperature. These findings present an important challenge to understanding the spectral evolution of WDs.

Infrared spectroscopic analysis of the effects of simulated space radiation on a polyimide

Science.gov (United States)

Ferl, J. E.; Long, E. R., Jr.

1981-01-01

Infrared spectroscopic techniques have been used to study the effects of electron radiation on the polyimide PMDA-p,p-prime- ODA. The radiation exposures were made at various dose rates, for a total dose approximately equal to that for 30 years of exposure to electron radiation in geosynchronous earth orbit. At high dose rates the major effect was probably the formation of a polyisoimide or a charged quaternary amine, and at the low dose rates the effect was a reduction in the amount or aromatic ether linkage. In addition, the effects of dose rate for a small total dose were studied. Elevated temperatures occurred at high dose rates and were, in part, probably the cause of the radiation product. The data suggest that dose rates for accelerated simulations of the space environment should not exceed 100,000 rads/sec.

Spectroscopic characterization of manganese-doped alkaline earth

Indian Academy of Sciences (India)

The intensity and frequency variations for the characteristic phosphate group vibrations have been correlated with the changes of the structural units present in these glasses. Depolymerization of the phosphate chains in all the glasses is observed with replacement of alkaline earth content by spectroscopic studies.

Quantification of UV-Visible and Laser Spectroscopic Techniques for Materials Accountability and Process Control

International Nuclear Information System (INIS)

Czerwinski, Kenneth; Weck, Phil

2013-01-01

Ultraviolet-visible spectroscopy (UV-Visible) and time-resolved laser fluorescence spectroscopy (TRLFS) optical techniques can permit on-line analysis of actinide elements in a solvent extraction process in real time. These techniques have been used for measuring actinide speciation and concentration under laboratory conditions and are easily adaptable to multiple sampling geometries, such as dip probes, fiber-optic sample cells, and flow-through cell geometries. To fully exploit these techniques, researchers must determine the fundamental speciation of target actinides and the resulting influence on spectroscopic properties. Detection limits, process conditions, and speciation of key actinide components can be established and utilized in a range of areas, particularly those related to materials accountability and process control. Through this project, researchers will develop tools and spectroscopic techniques to evaluate solution extraction conditions and concentrations of U, Pu, and Cm in extraction processes, addressing areas of process control and materials accountability. The team will evaluate UV- Visible and TRLFS for use in solvent extraction-based separations. Ongoing research is examining efficacy of UV-Visible spectroscopy to evaluate uranium and plutonium speciation under conditions found in the UREX process and using TRLFS to evaluate Cm speciation and concentration in the TALSPEAK process. A uranyl and plutonium nitrate UV-Visible spectroscopy study met with success, which supports the utility and continued exploration of spectroscopic methods for evaluation of actinide concentrations and solution conditions for other aspects of the UREX+ solvent extraction scheme. This project will examine U and Pu absorbance in TRUEX and TALSPEAK, perform detailed examination of Cm in TRUEX and TALSPEAK, study U laser fluorescence, and apply project data to contactors. The team will also determine peak ratios as a function of solution concentrations for the UV

A detailed spectroscopic study of an Italian fresco

International Nuclear Information System (INIS)

Barilaro, Donatella; Crupi, Vincenza; Majolino, Domenico; Barone, Germana; Ponterio, Rosina

2005-01-01

In the present work we characterized samples of plasters and pictorial layers taken from a fresco in the Acireale Cathedral. The fresco represents the Coronation of Saint Venera, patron saint of this Ionian town. By performing a detailed spectroscopic analysis of the plaster preparation layer by Fourier-transform infrared (FTIR) spectroscopy and x-ray diffraction (XRD), and of the painting layer by FTIR and confocal Raman microspectroscopy, scanning electron microscopy+energy dispersive x-ray spectroscopy, and XRD, we were able to identify the pigments and the binders present. In particular, Raman investigation was crucial to the characterization of the pigments thanks to the high resolution of the confocal apparatus used. It is worth stressing that the simultaneous use of complementary techniques was able to provide more complete information for the conservation of the artifact we studied

Raman spectroscopic study of “The Malatesta”: A Renaissance painting?

Science.gov (United States)

Edwards, Howell G. M.; Vandenabeele, Peter; Benoy, Timothy J.

2015-02-01

Raman spectroscopic analysis of the pigments on an Italian painting described as a "Full Length Portrait of a Gentleman", known also as the "Malatesta", and attributed to the Renaissance period has established that these are consistent with the historical research provenance undertaken earlier. Evidence is found for the early 19th Century addition of chrome yellow to highlighted yellow ochre areas in comparison with a similar painting executed in 1801 by Sir Thomas Lawrence of John Kemble in the role of Hamlet, Prince of Denmark. The Raman data are novel in that no analytical studies have previously been made on this painting and reinforces the procedure whereby scientific analyses are accompanied by parallel historical research.

Spectroscopic and asteroseismic analysis of the remarkable main-sequence A star KIC 11145123

Science.gov (United States)

Takada-Hidai, Masahide; Kurtz, Donald W.; Shibahashi, Hiromoto; Murphy, Simon J.; Takata, Masao; Saio, Hideyuki; Sekii, Takashi

2017-10-01

A spectroscopic analysis was carried out to clarify the properties of KIC 11145123 - the first main-sequence star with a directly measured core-to-surface rotation profile - based on spectra observed with the High Dispersion Spectrograph (HDS) of the Subaru telescope. The atmospheric parameters (Teff = 7600 K, log g = 4.2, ξ = 3.1 km s-1 and [Fe/H] = -0.71 dex), the radial and rotation velocities, and elemental abundances were obtained by analysing line strengths and fitting line profiles, which were calculated with a 1D LTE model atmosphere. The main properties of KIC 11145123 are: (1) a low [Fe/H] = -0.71 ± 0.11 dex and a high radial velocity of -135.4 ± 0.2 km s-1. These are remarkable among late-A stars. Our best asteroseismic models with this low [Fe/H] have slightly high helium abundance and low masses of 1.4 M⊙. All of these results strongly suggest that KIC 11145123 is a Population II blue straggler; (2) the projected rotation velocity confirms the asteroseismically predicted slow rotation of the star; (3) comparisons of abundance patterns between KIC 11145123 and Am, Ap, and blue stragglers show that KIC 11145123 is neither an Am star nor an Ap star, but has abundances consistent with a blue straggler. We conclude that the remarkably long 100-d rotation period of this star is a consequence of it being a blue straggler, but both pathways for the formation of blue stragglers - merger and mass loss in a binary system - pose difficulties for our understanding of the exceedingly slow rotation. In particular, we show that there is no evidence of any secondary companion star, and we put stringent limits on the possible mass of any such purported companion through the phase modulation technique.

Spectroscopic, thermal and biological studies of coordination

Indian Academy of Sciences (India)

Spectroscopic, thermal and biological studies of coordination compounds of sulfasalazine drug: Mn(II), Hg(II), Cr(III), ZrO(II), VO(II) and Y(III) transition metal ... The thermal decomposition of the complexes as well as thermodynamic parameters ( *}, *, * and *) were estimated using Coats–Redfern and ...

THE YOUNG SOLAR ANALOGS PROJECT. I. SPECTROSCOPIC AND PHOTOMETRIC METHODS AND MULTI-YEAR TIMESCALE SPECTROSCOPIC RESULTS

Energy Technology Data Exchange (ETDEWEB)

Gray, R. O.; Briley, M. M.; Lambert, R. A.; Fuller, V. A.; Newsome, I. M.; Seeds, M. F. [Department of Physics and Astronomy, Appalachian State University, Boone, NC 26808 (United States); Saken, J. M.; Kahvaz, Y. [Department of Physics and Physical Science, Marshall University, Huntington, WV 25755 (United States); Corbally, C. J. [Vatican Observatory Research Group, Steward Observatory, Tucson, AZ 85721-0065 (United States)

2015-12-15

This is the first in a series of papers presenting methods and results from the Young Solar Analogs Project, which began in 2007. This project monitors both spectroscopically and photometrically a set of 31 young (300–1500 Myr) solar-type stars with the goal of gaining insight into the space environment of the Earth during the period when life first appeared. From our spectroscopic observations we derive the Mount Wilson S chromospheric activity index (S{sub MW}), and describe the method we use to transform our instrumental indices to S{sub MW} without the need for a color term. We introduce three photospheric indices based on strong absorption features in the blue-violet spectrum—the G-band, the Ca i resonance line, and the Hydrogen-γ line—with the expectation that these indices might prove to be useful in detecting variations in the surface temperatures of active solar-type stars. We also describe our photometric program, and in particular our “Superstar technique” for differential photometry which, instead of relying on a handful of comparison stars, uses the photon flux in the entire star field in the CCD image to derive the program star magnitude. This enables photometric errors on the order of 0.005–0.007 magnitude. We present time series plots of our spectroscopic data for all four indices, and carry out extensive statistical tests on those time series demonstrating the reality of variations on timescales of years in all four indices. We also statistically test for and discover correlations and anti-correlations between the four indices. We discuss the physical basis of those correlations. As it turns out, the “photospheric” indices appear to be most strongly affected by emission in the Paschen continuum. We thus anticipate that these indices may prove to be useful proxies for monitoring emission in the ultraviolet Balmer continuum. Future papers in this series will discuss variability of the program stars on medium (days–months) and short

Proton MR spectroscopic imaging of basal ganglia and thalamus in neurofibromatosis type 1: correlation with T2 hyperintensities

International Nuclear Information System (INIS)

Barbier, Charlotte; Barantin, Laurent; Chabernaud, Camille; Bertrand, Philippe; Sembely, Catherine; Sirinelli, Dominique; Castelnau, Pierre; Cottier, Jean-Philippe

2011-01-01

Neurofibromatosis type 1 (NF1) is frequently associated with hyperintense lesions on T2-weighted images called ''unidentified bright objects'' (UBO). To better characterize the functional significance of UBO, we investigate the basal ganglia and thalamus using spectroscopic imaging in children with NF1 and compare the results to anomalies observed on T2-weighted images. Magnetic resonance (MR) data of 25 children with NF1 were analyzed. On the basis of T2-weighted images analysis, two groups were identified: one with normal MR imaging (UBO- group; n = 10) and one with UBO (UBO+ group; n = 15). Within the UBO+ group, a subpopulation of patients (n = 5) only had lesions of the basal ganglia. We analyzed herein seven regions of interest (ROIs) for each side: caudate nucleus, capsulo-lenticular region, lateral and posterior thalamus, thalamus (lateral and posterior voxels combined), putamen, and striatum. For each ROI, a spectrum of the metabolites and their ratio was obtained. Patients with abnormalities on T2-weighted images had significantly lower NAA/Cr, NAA/Cho, and NAA/mI ratios in the lateral right thalamus compared with patients with normal T2. These abnormal spectroscopic findings were not observed in capsulo-lenticular regions that had UBO but in the thalamus region that was devoid of UBO. Multivoxel spectroscopic imaging using short-time echo showed spectroscopic abnormalities in the right thalamus of NF1 patients harboring UBO, which were mainly located in the basal ganglia. This finding could reflect the anatomical and functional interactions of these regions. (orig.)

Potential energy curves and spectroscopic constants for the X1μ+ and A1μ+ states of the BeH+ Molecule

International Nuclear Information System (INIS)

Ornellas, F.R.

1982-02-01

Using a 1322-term configuration interaction wavefunction potential energy curves are computed for the ground (X 1 μ + ) and first excited (A 1 μ + ) states of the BeH + molecule. Spectroscopic constants are obtained by means of a Dunham analysis. (Author) [pt

Development of ultrasensitive spectroscopic analysis technology

International Nuclear Information System (INIS)

Cha, Hyung Ki; Song, K. S.; Kim, D. H.; Yang, K. H.; Jung, E. C.; Jeong, D. Y.; Yi, Y. J.; Lee, S. M.; Hong, K. H.; Han, J. M.; Yoo, B. D.; Rho, S. P.; Yi, J. H.; Park, H. M.; Cha, B. H.; Nam, S. M.; Lee, J. M.

1997-09-01

For the development of the laser initiated high resolution, ultra sensitive analysis technology following field of researches have been performed. 1) Laser resonance ionization technology, 2) Laser-induced rare isotope detection technology, 3) Laser-induced plasma analysis technology, 4) Microparticle analysis technology by using ion trap, 5) Laser induced remote sensing technique. As a result a monitoring system for photoionized product is developed and the test of system is performed with Sm sample. The rare isotope detection system is designed and a few key elements of the system are developed. In addition a laser-induced plasma analysis system is developed and samples such as Zircaloy, Zinc-base alloy, rock samples are reasonably analyzed. The detection sensitivity is identified as good as a few ppm order. An ion trap is developed and microparticles such as SiC are trapped inside the trap by ac and dc fields. The fluorescence signals from the organic dyes as well as rare earth element which are absorbed on the microparticles are detected. Several calibration curves are also obtained. In the field of laser remote sensing a mobile Lidar system is designed and several key elements are developed. In addition the developed system is used for the detection of Ozone, NO 2 , SO 2 , etc. (author). 57 refs., 42 figs

Spectroscopic investigation of Indium Bromide for lighting purposes

NARCIS (Netherlands)

Mulders, H.C.J.; Kroesen, G.M.W.; Haverlag, M.; Haverlag, M.; Kroesen, G.M.W.; Tagushi, T.

2010-01-01

Laser Induced Fluorescence was used to study the radiative properties of InBr for lighting purposes. Results include the temperature dependence of the fluorescence decay time, spectroscopic constants and rotational temperature determination from a LIF spectrum.

Application of spectroscopic techniques to the study of illuminated manuscripts: A survey

International Nuclear Information System (INIS)

Pessanha, S.; Manso, M.; Carvalho, M.L.

2012-01-01

This work focused on the application of the most relevant spectroscopic techniques used for the characterization of illuminated manuscripts. The historical value of these unique and invaluable artworks, together with the increased awareness concerning the conservation of cultural heritage, prompted the application of analytical techniques to the study of these illuminations. This is essential for the understanding of the artist's working methods, which aids conservation–restoration. The characterization of the pigments may also help assign a probable date to the manuscript. For these purposes, the spectroscopic techniques used so far include those that provide information on the elemental content: X-ray fluorescence, total reflection X-ray fluorescence and scanning electron microscopy coupled with energy-dispersive spectroscopy and laser-induced breakdown spectroscopy. Complementary techniques, such as X-ray diffraction, Fourier transform infrared and Raman spectroscopy, reveal information regarding the compounds present in the samples. The techniques, suitability, technological evolution and development of high-performance detectors, as well as the possibility of microanalysis and the higher sensitivity of the equipment, will also be discussed. Furthermore, issues such as the necessity of sampling, the portability of the equipment and the overall advantages and disadvantages of different techniques will be analyzed. - Highlights: ► The techniques used for studying illuminated manuscripts are described and compared. ► For in situ, non-destructive analysis the most suitable technique is EDXRF. ► For quantitative analysis TXRF is more appropriate. ► Raman spectroscopy is mostly used for pigments identification. ► FTIR was used for the characterization of binders and parchment.

Principles of spectroscopic diagnostics of a plasma with oscillating electric fields

International Nuclear Information System (INIS)

Oks, E.A.

1986-01-01

Three types of main principles of spectroscopic diagnosis of the plasma with quasimonochromatic electric fields (QEF) are considered. Principles based on the effects intersectionally depending on the parameters of QEF and the plasma medium are considered. Occurrence of depressions or dips in the profiles of spectral lines is the most important effect among others. Principles based on the nonlinear theory of plasma and laser sattelites of spectral lines as well as laser-spectroscopic diagnosis of QEF in the plasma are considered

THE GALACTIC O-STAR SPECTROSCOPIC SURVEY (GOSSS). III. 142 ADDITIONAL O-TYPE SYSTEMS

International Nuclear Information System (INIS)

Apellániz, J. Maíz; Sota, A.; Alfaro, E. J.; Arias, J. I.; Barbá, R. H.; Walborn, N. R.; Simón-Díaz, S.; Herrero, A.; Negueruela, I.; Marco, A.; Leão, J. R. S.; Gamen, R. C.

2016-01-01

This is the third installment of the Galactic O-Star Spectroscopic Survey (GOSSS), a massive spectroscopic survey of Galactic O stars, based on new homogeneous, high signal-to-noise ratio, R  ∼ 2500 digital observations selected from the Galactic O-Star Catalog. In this paper, we present 142 additional stellar systems with O stars from both hemispheres, bringing the total of O-type systems published within the project to 590. Among the new objects, there are 20 new O stars. We also identify 11 new double-lined spectroscopic binaries, 6 of which are of O+O type and 5 of O+B type, and an additional new tripled-lined spectroscopic binary of O+O+B type. We also revise some of the previous GOSSS classifications, present some egregious examples of stars erroneously classified as O-type in the past, introduce the use of luminosity class IV at spectral types O4-O5.5, and adapt the classification scheme to the work of Arias et al.

THE GALACTIC O-STAR SPECTROSCOPIC SURVEY (GOSSS). III. 142 ADDITIONAL O-TYPE SYSTEMS

Energy Technology Data Exchange (ETDEWEB)

Apellániz, J. Maíz [Centro de Astrobiología, CSIC-INTA, campus ESAC, camino bajo del castillo s/n, E-28 692 Madrid (Spain); Sota, A.; Alfaro, E. J. [Instituto de Astrofísica de Andalucía-CSIC, Glorieta de la Astronomía s/n, E-18 008 Granada (Spain); Arias, J. I.; Barbá, R. H. [Departamento de Física, Universidad de La Serena, Av. Cisternas 1200 Norte, La Serena (Chile); Walborn, N. R. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21 218 (United States); Simón-Díaz, S.; Herrero, A. [Instituto de Astrofísica de Canarias, E-38 200 La Laguna, Tenerife (Spain); Negueruela, I.; Marco, A. [DFISTS, EPS, Universidad de Alicante, carretera San Vicente del Raspeig s/n, E-03 690 Alicante (Spain); Leão, J. R. S. [Univ. Federal do Rio Grande do Norte—UFRN, Caixa Postal 1524, CEP 59 078-970, Natal—RN (Brazil); Gamen, R. C., E-mail: jmaiz@cab.inta-csic.es [Instituto de Astrofísica de La Plata (CONICET, UNLP), Paseo del Bosque s/n, 1900 La Plata (Argentina)

2016-05-01

This is the third installment of the Galactic O-Star Spectroscopic Survey (GOSSS), a massive spectroscopic survey of Galactic O stars, based on new homogeneous, high signal-to-noise ratio, R  ∼ 2500 digital observations selected from the Galactic O-Star Catalog. In this paper, we present 142 additional stellar systems with O stars from both hemispheres, bringing the total of O-type systems published within the project to 590. Among the new objects, there are 20 new O stars. We also identify 11 new double-lined spectroscopic binaries, 6 of which are of O+O type and 5 of O+B type, and an additional new tripled-lined spectroscopic binary of O+O+B type. We also revise some of the previous GOSSS classifications, present some egregious examples of stars erroneously classified as O-type in the past, introduce the use of luminosity class IV at spectral types O4-O5.5, and adapt the classification scheme to the work of Arias et al.

The selection function of the LAMOST Spectroscopic Survey of the Galactic Anti-centre

Science.gov (United States)

Chen, B.-Q.; Liu, X.-W.; Yuan, H.-B.; Xiang, M.-S.; Huang, Y.; Wang, C.; Zhang, H.-W.; Tian, Z.-J.

2018-05-01

We present a detailed analysis of the selection function of the LAMOST Spectroscopic Survey of the Galactic Anti-centre (LSS-GAC). LSS-GAC was designed to obtain low-resolution optical spectra for a sample of more than 3 million stars in the Galactic anti-centre. The second release of value-added catalogues of the LSS-GAC (LSS-GAC DR2) contains stellar parameters, including radial velocity, atmospheric parameters, elemental abundances, and absolute magnitudes deduced from 1.8 million spectra of 1.4 million unique stars targeted by the LSS-GAC between 2011 and 2014. For many studies using this data base, such as those investigating the chemodynamical structure of the Milky Way, a detailed understanding of the selection function of the survey is indispensable. In this paper, we describe how the selection function of the LSS-GAC can be evaluated to sufficient detail and provide selection function corrections for all spectroscopic measurements with reliable parameters released in LSS-GAC DR2. The results, to be released as new entries in the LSS-GAC value-added catalogues, can be used to correct the selection effects of the catalogue for scientific studies of various purposes.

Combined crystallographic and spectroscopic analysis of Trematomus bernacchii hemoglobin highlights analogies and differences in the peculiar oxidation pathway of Antarctic fish hemoglobins.

Science.gov (United States)

Merlino, Antonello; Vitagliano, Luigi; Howes, Barry D; Verde, Cinzia; di Prisco, Guido; Smulevich, Giulietta; Sica, Filomena; Vergara, Alessandro

2009-12-01

Recent studies have demonstrated that hemoglobins isolated from Antarctic fish undergo peculiar oxidation processes. Here we show, by combining crystallographic and spectroscopic data, that the oxidation pathway of Trematomus bernacchii hemoglobin (HbTb) is distinct from that observed for the major component of Trematomus newnesi (Hb1Tn), despite the high sequence identity of the two proteins and structural similarity of their ferrous and fully oxidized states. Resonance Raman analysis of HbTb autoxidation upon air-exposure reveals the absence of the oxidized pentacoordinated state that was observed for Hb1Tn. The HbTb oxidation pathway is characterized by two ferric species: an aquo hexacoordinated high spin state and a bis-histidyl hexacoordinated low spin form, which appear in the early stages of the oxidation process. The high resolution structure of an intermediate along the oxidation pathway has been determined at 1.4 A resolution. The analysis of the electron density of the heme pocket shows, for both the alpha and the beta iron, the coexistence of multiple binding states. In this partially oxidized form, HbTb exhibits significant deviations from the canonical R state both at the local and global level. The analysis of these modifications highlights the structural correlation between key functional regions of the protein.

Spectroscopic characterisation of the stellar content of ultra diffuse galaxies

Science.gov (United States)

Ruiz-Lara, T.; Beasley, M. A.; Falcón-Barroso, J.; Román, J.; Pinna, F.; Brook, C.; Di Cintio, A.; Martín-Navarro, I.; Trujillo, I.; Vazdekis, A.

2018-05-01

Understanding the peculiar properties of Ultra Diffuse Galaxies (UDGs) via spectroscopic analysis is a challenging task requiring very deep observations and exquisite data reduction. In this work we perform one of the most complete characterisations of the stellar component of UDGs to date using deep optical spectroscopic data from OSIRIS at GTC. We measure radial and rotation velocities, star formation histories (SFH) and mean population parameters, such as ages and metallicities, for a sample of five UDG candidates in the Coma cluster. From the radial velocities, we confirm the Coma membership of these galaxies. We find that their rotation properties, if detected at all, are compatible with dwarf-like galaxies. The SFHs of the UDG are dominated by old (˜ 7 Gyr), metal-poor ([M/H] ˜ -1.1) and α-enhanced ([Mg/Fe] ˜ 0.4) populations followed by a smooth or episodic decline which halted ˜ 2 Gyr ago, possibly a sign of cluster-induced quenching. We find no obvious correlation between individual SFH shapes and any UDG morphological properties. The recovered stellar properties for UDGs are similar to those found for DDO 44, a local UDG analogue resolved into stars. We conclude that the UDGs in our sample are extended dwarfs whose properties are likely the outcome of both internal processes, such as bursty SFHs and/or high-spin haloes, as well as environmental effects within the Coma cluster.

Development of ultrasensitive spectroscopic analysis technology

Energy Technology Data Exchange (ETDEWEB)

Cha, Hyung Ki; Song, K S; Kim, D H; Yang, K H; Jung, E C; Jeong, D Y; Yi, Y J; Lee, S M; Hong, K H; Han, J M; Yoo, B D; Rho, S P; Yi, J H; Park, H M; Cha, B H; Nam, S M; Lee, J M

1997-09-01

For the development of the laser initiated high resolution, ultra sensitive analysis technology following field of researches have been performed. (1) Laser resonance ionization technology, (2) Laser-induced rare isotope detection technology, (3) Laser-induced plasma analysis technology, (4) Microparticle analysis technology by using ion trap, (5) Laser induced remote sensing technique. As a result a monitoring system for photoionized product is developed and the test of system is performed with Sm sample. The rare isotope detection system is designed and a few key elements of the system are developed. In addition a laser-induced plasma analysis system is developed and samples such as Zircaloy, Zinc-base alloy, rock samples are reasonably analyzed. The detection sensitivity is identified as good as a few ppm order. An ion trap is developed and microparticles such as SiC are trapped inside the trap by ac and dc fields. The fluorescence signals from the organic dyes as well as rare earth element which are absorbed on the microparticles are detected. Several calibration curves are also obtained. In the field of laser remote sensing a mobile Lidar system is designed and several key elements are developed. In addition the developed system is used for the detection of Ozone, NO{sub 2}, SO{sub 2}, etc. (author). 57 refs., 42 figs.

A nearly on-axis spectroscopic system for simultaneously measuring UV-visible absorption and X-ray diffraction in the SPring-8 structural genomics beamline.

Science.gov (United States)

Sakaguchi, Miyuki; Kimura, Tetsunari; Nishida, Takuma; Tosha, Takehiko; Sugimoto, Hiroshi; Yamaguchi, Yoshihiro; Yanagisawa, Sachiko; Ueno, Go; Murakami, Hironori; Ago, Hideo; Yamamoto, Masaki; Ogura, Takashi; Shiro, Yoshitsugu; Kubo, Minoru

2016-01-01

UV-visible absorption spectroscopy is useful for probing the electronic and structural changes of protein active sites, and thus the on-line combination of X-ray diffraction and spectroscopic analysis is increasingly being applied. Herein, a novel absorption spectrometer was developed at SPring-8 BL26B2 with a nearly on-axis geometry between the X-ray and optical axes. A small prism mirror was placed near the X-ray beamstop to pass the light only 2° off the X-ray beam, enabling spectroscopic analysis of the X-ray-exposed volume of a crystal during X-ray diffraction data collection. The spectrometer was applied to NO reductase, a heme enzyme that catalyzes NO reduction to N2O. Radiation damage to the heme was monitored in real time during X-ray irradiation by evaluating the absorption spectral changes. Moreover, NO binding to the heme was probed via caged NO photolysis with UV light, demonstrating the extended capability of the spectrometer for intermediate analysis.

Spectroscopic studies of pulsed-power plasmas

International Nuclear Information System (INIS)

Maron, Y.; Arad, R.; Dadusc, G.; Davara, G.; Duvall, R.E.; Fisher, V.; Foord, M.E.; Fruchtman, A.; Gregorian, L.; Krasik, Ya.

1993-01-01

Recently developed spectroscopic diagnostic techniques are used to investigate the plasma behavior in a Magnetically Insulated Ion Diode, a Plasma Opening Switch, and a gas-puffed Z-pinch. Measurements with relatively high spectral, temporal, and spatial resolutions are performed. The particle velocity and density distributions within a few tens of microns from the dielectric-anode surface are observed using laser spectroscopy. Collective fluctuating electric fields in the plasma are inferred from anisotropic Stark broadening. For the Plasma Opening Switch experiment, a novel gaseous plasma source was developed which is mounted inside the high-voltage inner conductor. The properties of this source, together with spectroscopic observations of the electron density and particle velocities of the injected plasma, are described. Emission line intensities and spectral profiles give the electron kinetic energies during the switch operation and the ion velocity distributions. Secondary plasma ejection from the electrodes is also studied. In the Z-pinch experiment, spectral emission-line profiles are studied during the implosion phase. Doppler line shifts and widths yield the radial velocity distributions for various charge states in various regions of the plasma. Effects of plasma ejection from the cathode are also studied

The HITRAN 2004 molecular spectroscopic database

Energy Technology Data Exchange (ETDEWEB)

Rothman, L.S. [Harvard-Smithsonian Center for Astrophysics, Atomic and Molecular Physics Division, Cambridge, MA 02138 (United States)]. E-mail: lrothman@cfa.harvard.edu; Jacquemart, D. [Harvard-Smithsonian Center for Astrophysics, Atomic and Molecular Physics Division, Cambridge, MA 02138 (United States); Barbe, A. [Universite de Reims-Champagne-Ardenne, Groupe de Spectrometrie Moleculaire et Atmospherique, 51062 Reims (France)] (and others)

2005-12-01

This paper describes the status of the 2004 edition of the HITRAN molecular spectroscopic database. The HITRAN compilation consists of several components that serve as input for radiative transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e., spectra in which the individual lines are unresolvable; individual line parameters and absorption cross-sections for bands in the ultra-violet; refractive indices of aerosols; tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 39 molecules including many of their isotopologues. The format of the section of the database on individual line parameters of HITRAN has undergone the most extensive enhancement in almost two decades. It now lists the Einstein A-coefficients, statistical weights of the upper and lower levels of the transitions, a better system for the representation of quantum identifications, and enhanced referencing and uncertainty codes. In addition, there is a provision for making corrections to the broadening of line transitions due to line mixing.

The HITRAN 2004 molecular spectroscopic database

International Nuclear Information System (INIS)

Rothman, L.S.; Jacquemart, D.; Barbe, A.

2005-01-01

This paper describes the status of the 2004 edition of the HITRAN molecular spectroscopic database. The HITRAN compilation consists of several components that serve as input for radiative transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e., spectra in which the individual lines are unresolvable; individual line parameters and absorption cross-sections for bands in the ultra-violet; refractive indices of aerosols; tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 39 molecules including many of their isotopologues. The format of the section of the database on individual line parameters of HITRAN has undergone the most extensive enhancement in almost two decades. It now lists the Einstein A-coefficients, statistical weights of the upper and lower levels of the transitions, a better system for the representation of quantum identifications, and enhanced referencing and uncertainty codes. In addition, there is a provision for making corrections to the broadening of line transitions due to line mixing

Spectroscopic studies of 2-thenoyltrifluoro acetonate of uranyl salts doped with europium

International Nuclear Information System (INIS)

Nakagawa, F.T.; Luiz, J.E.M. de Sa; Felinto, M.C.F.C.; Brito, H.F.; Teotonio, E.E.S.

2006-01-01

Uranyl compounds present a great potential as luminescence materials. Some examples of applications are: in laser technology, cathode ray tube, X-rays diagnostic. In this work it was studied the synthesis, characterization and spectroscopic properties study of uranyl 2-thenoyl trifluoroacetonate and uranyl 2- thenoyl trifluoroacetonate doped with europium. The compounds were synthesized and characterized by infrared absorption spectroscopy, thermal analysis, scanning electronic microscopy, and electronic spectroscopy of emission and excitation. The Eu 3+ ion acted as an effective luminescent probe, however the process of energy transfer from UO 2 2+ to Eu 3+ ion has not been efficient. (author)

Interaction of methotrexate with trypsin analyzed by spectroscopic and molecular modeling methods

Science.gov (United States)

Wang, Yanqing; Zhang, Hongmei; Cao, Jian; Zhou, Qiuhua

2013-11-01

Trypsin is one of important digestive enzymes that have intimate correlation with human health and illness. In this work, the interaction of trypsin with methotrexate was investigated by spectroscopic and molecular modeling methods. The results revealed that methotrexate could interact with trypsin with about one binding site. Methotrexate molecule could enter into the primary substrate-binding pocket, resulting in inhibition of trypsin activity. Furthermore, the thermodynamic analysis implied that electrostatic force, hydrogen bonding, van der Waals and hydrophobic interactions were the main interactions for stabilizing the trypsin-methotrexate system, which agreed well with the results from the molecular modeling study.

Synthesis, Spectroscopic Properties and DFT Calculation of Novel ...

Indian Academy of Sciences (India)

L1) identifies its molecular structure and reveals π-π stacking. The synthetic mechanisms for L2, L3 were studied by density functional theory calculations. And a comprehensive study of spectroscopic properties involving experimental data and ...

Spectroscopic properties of Pr -doped erbium oxalate crystals

Indian Academy of Sciences (India)

Spectroscopic properties of praseodymium ions-doped erbium oxalate ... solution with specific gravity 1.04 g/cm3 was mixed homogeneously with 0.5 M oxalic ... of concentrated nitric acid were transferred carefully and gently through the wall ...

SPECTROSCOPIC AND PHOTOMETRIC VARIABILITY IN THE A0 SUPERGIANT HR 1040

International Nuclear Information System (INIS)

Corliss, David J.; Morrison, Nancy D.; Adelman, Saul J.

2015-01-01

A time-series analysis of spectroscopic and photometric observables of the A0 Ia supergiant HR 1040 has been performed, including equivalent widths, radial velocities, and Strömgren photometric indices. The data, obtained from 1993 through 2007, include 152 spectroscopic observations from the Ritter Observatory 1 m telescope and 269 Strömgren photometric observations from the Four College Automated Photoelectric Telescope. Typical of late B- and early A-type supergiants, HR 1040 has a highly variable Hα profile. The star was found to have an intermittent active phase marked by correlation between the Hα absorption equivalent width and blue-edge radial velocity and by photospheric connections observed in correlations to equivalent width, second moment and radial velocity in Si ii λλ6347, 6371. High-velocity absorption (HVA) events were observed only during this active phase. HVA events in the wind were preceded by photospheric activity, including Si ii radial velocity oscillations 19–42 days prior to onset of an HVA event and correlated increases in Si ii W λ and second moment from 13 to 23 days before the start of the HVA event. While increases in various line equivalent widths in the wind prior to HVA events have been reported in the past in other stars, our finding of precursors in enhanced radial velocity variations in the wind and at the photosphere is a new result

Confirming LBV Candidates Through Variability: A Photometric and Spectroscopic Monitoring Study

Science.gov (United States)

Stringfellow, Guy; Gvaramadze, Vasilii

2013-02-01

Luminous Blue Variable (LBV) stars represent an extremely rare class of luminous massive stars with high mass loss rates. The paucity ( 12) of confirmed Galactic LBV precludes determining a solid evolutionary connection between LBV and other intermediate (e.g. Ofpe/WN9, WNL) phases in the life of very massive stars. We've been conducting an optical/near-IR spectral survey of a large subset of central stars residing within newly discovered it Spitzer nebulae and have identified over two dozen new candidate LBVs (cLBVs) based on spectral similarity alone; confirming them as bona fide LBVs requires demonstrating 1-3 mag photometric and spectroscopic variability. This marks a significant advancement in the study of massive stars, far outweighing the return from many studies searching for LBVs and WRs the past several decades. Monitoring from semesters 2011B-2012A already has confirmed one new cLBV as a bona fide LBV. We propose to continue optical-IR photometric monitoring of these cLBVS with the 1.3m. Chiron, replacing the RC spectrograph on the 1.5m, now allows high-resolution optical spectroscopic monitoring of bright cLBVs, 11 of which are proposed herein. Spectra are important for understanding the physics driving photometric variability, properties of the wind, and allow analysis of line profiles.

Spectroscopic properties for identifying sapphire samples from Ban Bo Kaew, Phrae Province, Thailand

Science.gov (United States)

Mogmued, J.; Monarumit, N.; Won-in, K.; Satitkune, S.

2017-09-01

Gemstone commercial is a high revenue for Thailand especially ruby and sapphire. Moreover, Phrae is a potential gem field located in the northern part of Thailand. The studies of spectroscopic properties are mainly to identify gemstone using advanced techniques (e.g. UV-Vis-NIR spectrophotometry, FTIR spectrometry and Raman spectroscopy). Typically, UV-Vis-NIR spectrophotometry is a technique to study the cause of color in gemstones. FTIR spectrometry is a technique to study the functional groups in gem-materials. Raman pattern can be applied to identify the mineral inclusions in gemstones. In this study, the natural sapphires from Ban Bo Kaew were divided into two groups based on colors including blue and green. The samples were analyzed by UV-Vis-NIR spectrophotometer, FTIR spectrometer and Raman spectroscope for studying spectroscopic properties. According to UV-Vis-NIR spectra, the blue sapphires show higher Fe3+/Ti4+ and Fe2+/Fe3+ absorption peaks than those of green sapphires. Otherwise, green sapphires display higher Fe3+/Fe3+ absorption peaks than blue sapphires. The FTIR spectra of both blue and green sapphire samples show the absorption peaks of -OH,-CH and CO2. The mineral inclusions such as ferrocolumbite and rutile in sapphires from this area were observed by Raman spectroscope. The spectroscopic properties of sapphire samples from Ban Bo Kaew, Phrae Province, Thailand are applied to be the specific evidence for gemstone identification.

Morphological and spectroscopic analysis of cellulose nanocrystals extracted from oil palm empty fruit bunch fiber

Energy Technology Data Exchange (ETDEWEB)

Dasan, Y. K., E-mail: aamir.bhat@petronas.com.my; Bhat, A. H., E-mail: aamir.bhat@petronas.com.my [Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, 31750, Bandar Seri Iskandar, Perak (Malaysia); Faiz, A., E-mail: faizahmad@petronas.com.my [Department of Mechanical Engineering, Universiti Teknologi PETRONAS, 31750, Bandar Seri Iskandar, Perak (Malaysia)

2015-07-22

This work evaluates the use of oil palm empty fruit bunch (OPEFB) fiber as a source of cellulose to obtain nanocrystalline cellulose (CNC) by acid hydrolysis reaction. The raw OPEFB fibers were pretreated with aqueous Sodium hydroxide at 80°C followed by bleaching treatment and further hydrolyzed with Sulphuric acid at 45°C with limited range of hydrolysis time and acid concentration. The resulting CNC’s were characterized for spectroscopic, crystallographic and morphological properties using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometer (XRD), Transmission Electron Microscope (TEM) and Atomic Force Microscopy (AFM). Finding of this study shows that the properties of CNC’s are strongly dependent on the hydrolysis time and acid concentration.

Investigating Functional Extension of Optical Coherence Tomography for Spectroscopic Analysis of Blood Oxygen Saturation

Science.gov (United States)

Chen, Siyu

Over the past two decades, optical coherence tomography (OCT) has been successfully applied to various fields of biomedical researching and clinical studies, including cardiology, urology, dermatology, dentistry, oncology, and most successfully, ophthalmology. This dissertation seeks to extend the current OCT practice, which is still largely morphology-based, into a new dimension, functional analysis of metabolic activities in vivo. More specifically, the investigation is focused on retrieving blood oxygen saturation (sO2) using intrinsic hemoglobin optical absorption contrast. Most mammalian cells rely on aerobic respiration to support cellular function, which means they consume oxygen to create adenosine triphosphate (ATP). Metabolic rate of oxygen (MRO2), a key hemodynamic parameter, characterizes how much oxygen is consumed during a given period of time, reflecting the metabolic activity of the target tissue. For example, retinal neurons are highly active and almost entirely rely on the moment-to-moment oxygen supply from retinal circulations. Thus, variation in MRO2 reveals the instantaneous activity of these neurons, shedding light on the physiological and pathophysiological change of cellular functions. Eventually, measuring MRO2 can potentially provide a biomarker for early-stage disease diagnosis, and serve as one benchmark for evaluating effectiveness of medical intervention during disease management. Essential in calculating MRO2, blood sO2 measurements using spectroscopic OCT analysis has been attempted as early as 2003. OCT is intrinsically sensitive to the blood optical absorption spectrum due to its wide-band illumination and detection scheme relying on back-scattered photon. However, accurate retrieval of blood sO2 using conventional near infrared (NIR) OCT systems in vivo has remained challenging. It was not until the development of OCT systems using visible light illumination (vis-OCT) when accurate measurement of blood sO2 was reported in live

Metabolic networks in epilepsy by MR spectroscopic imaging.

Science.gov (United States)

Pan, J W; Spencer, D D; Kuzniecky, R; Duckrow, R B; Hetherington, H; Spencer, S S

2012-12-01

The concept of an epileptic network has long been suggested from both animal and human studies of epilepsy. Based on the common observation that the MR spectroscopic imaging measure of NAA/Cr is sensitive to neuronal function and injury, we use this parameter to assess for the presence of a metabolic network in mesial temporal lobe epilepsy (MTLE) patients. A multivariate factor analysis is performed with controls and MTLE patients, using NAA/Cr measures from 12 loci: the bilateral hippocampi, thalami, basal ganglia, and insula. The factor analysis determines which and to what extent these loci are metabolically covarying. We extract two independent factors that explain the data's variability in control and MTLE patients. In controls, these factors characterize a 'thalamic' and 'dominant subcortical' function. The MTLE patients also exhibit a 'thalamic' factor, in addition to a second factor involving the ipsilateral insula and bilateral basal ganglia. These data suggest that MTLE patients demonstrate a metabolic network that involves the thalami, also seen in controls. The MTLE patients also display a second set of metabolically covarying regions that may be a manifestation of the epileptic network that characterizes limbic seizure propagation. © 2012 John Wiley & Sons A/S.

Photoelectric Radial Velocities, Paper XIX Additional Spectroscopic ...

Indian Academy of Sciences (India)

ian velocity curve that does justice to the measurements, but it cannot be expected to have much predictive power. Key words. Stars: late-type—stars: radial velocities—spectroscopic binaries—orbits. 0. Preamble. The 'Redman K stars' are a lot of seventh-magnitude K stars whose radial velocities were first observed by ...

SPECTROSCOPIC AND INTERFEROMETRIC MEASUREMENTS OF NINE K GIANT STARS

Energy Technology Data Exchange (ETDEWEB)

Baines, Ellyn K. [Remote Sensing Division, Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375 (United States); Döllinger, Michaela P. [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Guenther, Eike W.; Hatzes, Artie P. [Thüringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg (Germany); Hrudkovu, Marie [Isaac Newton Group of Telescopes, Apartado de Correos 321, E-387 00 Santa Cruz de la Palma, Canary Islands (Spain); Belle, Gerard T. van, E-mail: ellyn.baines@nrl.navy.mil [Lowell Observatory, Flagstaff, AZ 86001 (United States)

2016-09-01

We present spectroscopic and interferometric measurements for a sample of nine K giant stars. These targets are of particular interest because they are slated for stellar oscillation observations. Our improved parameters will directly translate into reduced errors in the final masses for these stars when interferometric radii and asteroseismic densities are combined. Here, we determine each star’s limb-darkened angular diameter, physical radius, luminosity, bolometric flux, effective temperature, surface gravity, metallicity, and mass. When we compare our interferometric and spectroscopic results, we find no systematic offsets in the diameters and the values generally agree within the errors. Our interferometric temperatures for seven of the nine stars are hotter than those determined from spectroscopy with an average difference of about 380 K.

Interaction of Lysozyme with Rhodamine B: A combined analysis of spectroscopic & molecular docking.

Science.gov (United States)

Millan, Sabera; Satish, Lakkoji; Kesh, Sandeep; Chaudhary, Yatendra S; Sahoo, Harekrushna

2016-09-01

The interaction of Rhodamine B (RB) with Lysozyme (Lys) was investigated by different optical spectroscopic techniques such as absorption, fluorescence, and circular-dichroism (CD), along with molecular docking studies. The fluorescence results (including steady-state and time-resolved mode) revealed that the addition of RB effectively causes strong quenching of intrinsic fluorescence in Lysozyme and mostly, by the static quenching mechanism. Different binding and thermodynamic parameters were calculated at different temperatures and the binding constant value was found to be 2963.54Lmol(-1) at 25°C. The average distance (r0) was found to be 3.31nm according to Förster's theory of non-radiative energy transfer between Lysozyme and RB. The conformational change in Lysozyme during interaction with RB was confirmed from absorbance, synchronous fluorescence, and circular dichroism measurements. Finally, molecular docking studies were done to confirm that the dye binds with Lysozyme. Copyright © 2016 Elsevier B.V. All rights reserved.

ePESSTO spectroscopic classification of the candidate TDE XMMSL2 J140446.9-251135

Science.gov (United States)

Taubenberger, S.; Floers, A.; Vogl, C.; Benetti, S.; Pastorello, A.; Cappellaro, E.; Anderson, J.; Gromadzki, M.; Onori, F.; Kostrzewa-Rutkowska, Z.; Jonker, P.; Leloudas, G.; Inserra, C.; Kankare, E.; Maguire, K.; Smartt, S. J.; Yaron, O.; Young, D.

2018-03-01

ePESSTO, the extended Public ESO Spectroscopic Survey for Transient Objects (see Smartt et al. 2015, A & A, 579, 40; http://www.pessto.org ), reports the following spectroscopic observation of the new X-ray source XMMSL2 J140446.9-251135 in the galaxy 2MASX 14044671-2511433 (ATel #11394).

2-d spectroscopic imaging of brain tumours

International Nuclear Information System (INIS)

Ferris, N.J.; Brotchie, P.R.

2002-01-01

Full text: This poster illustrates the use of two-dimensional spectroscopic imaging (2-D SI) in the characterisation of brain tumours, and the monitoring of subsequent treatment. After conventional contrast-enhanced MR imaging of patients with known or suspected brain tumours, 2-D SI is performed at a single axial level. The level is chosen to include the maximum volume of abnormal enhancement, or, in non-enhancing lesions. The most extensive T2 signal abnormality. Two different MR systems have been used (Marconi Edge and GE Signa LX); at each site, a PRESS localisation sequence is employed with TE 128-144 ms. Automated software is used to generate spectral arrays, metabolite maps, and metabolite ratio maps from the spectroscopic data. Colour overlays of the maps onto anatomical images are produced using manufacturer software or the Medex imaging data analysis package. High grade gliomas showed choline levels higher than those in apparently normal brain, with decreases in NAA and creatine. Some lesions showed spectral abnormality extending into otherwise normal appearing brain. This was also seen in a case of CNS lymphoma. Lowgrade lesions showed choline levels similar to normal brain, but with decreased NAA. Only a small number of metastases have been studied, but to date no metastasis has shown spectral abnormality beyond the margins suggested by conventional imaging. Follow-up studies generally show spectral heterogeneity. Regions with choline levels higher than those in normal-appearing brain are considered to represent recurrent high-grade tumour. Some regions show choline to be the dominant metabolite, but its level is not greater than that seen in normal brain. These regions are considered suspicious for residual / recurrent tumour when the choline / creatine ratio exceeds 2 (lower ratios may represent treatment effect). 2-D SI improves the initial assessment of brain tumours, and has potential for influencing the radiotherapy treatment strategy. 2-D SI also

Synthesis, spectroscopic, and molecular structure characterizations of some azo derivatives of 2-hydroxyacetophenone

Science.gov (United States)

Albayrak, Çiğdem; Gümrükçüoğlu, İsmail E.; Odabaşoğlu, Mustafa; İskeleli, Nazan Ocak; Ağar, Erbil

2009-08-01

Some novel azo compounds were prepared by the reaction of 2-hydroxyacetophenone with aniline and its substituted derivatives. The structures of synthesized azo compounds were determined by IR, UV-Vis, 1H NMR and 13C NMR spectroscopic techniques and the structures of some of these compounds were also determined by X-ray diffraction studies. Structural analysis using IR in solid state shows that the azo form is favoured in the azo compounds whereas UV-Vis analysis of the azo compounds in solution has shown that there is a azo and ionic form. The azo compounds in the basic solvents dimethylformamide (DMF) and dimethylsulfoxide (DMSO) are both azo and ionic form while these compounds in ethyl alcohol (EtOH) and chloroform (CHCl 3) are only azo form.

Natural organic UV-absorbent coatings based on cellulose and lignin: designed effects on spectroscopic properties.

Science.gov (United States)

Hambardzumyan, Arayik; Foulon, Laurence; Chabbert, Brigitte; Aguié-Béghin, Véronique

2012-12-10

Novel nanocomposite coatings composed of cellulose nanocrystals (CNCs) and lignin (either synthetic or fractionated from spruce and corn stalks) were prepared without chemical modification or functionalization (via covalent attachment) of one of the two biopolymers. The spectroscopic properties of these coatings were investigated by UV-visible spectrophotometry and spectroscopic ellipsometry. When using the appropriate weight ratio of CNC/lignin (R), these nanocomposite systems exhibited high-performance optical properties, high transmittance in the visible spectrum, and high blocking in the UV spectrum. Atomic force microscopy analysis demonstrated that these coatings were smooth and homogeneous, with visible dispersed lignin nodules in a cellulosic matrix. It was also demonstrated that the introduction of nanoparticles into the medium increases the weight ratio and the CNC-specific surface area, which allows better dispersion of the lignin molecules throughout the solid film. Consequently, the larger molecular expansion of these aromatic polymers on the surface of the cellulosic nanoparticles dislocates the π-π aromatic aggregates, which increases the extinction coefficient and decreases the transmittance in the UV region. These nanocomposite coatings were optically transparent at visible wavelengths.

Spectroscopic orbit for HDE 245770 A0535+26

International Nuclear Information System (INIS)

Hutchings, J.B.

1984-01-01

Optical spectroscopic data are examined using the X-ray intensity period of 111 days. Optical and X-ray pulse-timing orbit parameters agree well and indicate an eccentricity of approximately 0.3. Masses of the stars and periastron effects are discussed. 6 references

Molecular structure, vibrational spectroscopic analysis (IR & Raman), HOMO-LUMO and NBO analysis of anti-cancer drug sunitinib using DFT method

Science.gov (United States)

Mıhçıokur, Özlem; Özpozan, Talat

2017-12-01

Oxindole and its derivatives have wide applications in different industries such as in synthetic & natural fibers, dyes for hair and plastic materials in addition to their biological importance. In the present study, one of the oxindole derivatives, N-(2-diethylaminoethyl)-5-[(Z)-(5-fluoro-2-oxo-1H-indol-3-ylidene)methyl]-2,4-dimethyl-1H-pyrrole-3-carboxamide (Sunitinib), which is used as an anti-cancer drug, was investigated in terms of structural, vibrational spectroscopic and theoretical analysis. The calculations have been performed for gaseous, aqueous and DMSO phases, respectively. Potential Energy Surface (PES) scan has been carrried out to obtain the most stable structures of all the phases of the title molecule using B3LYP/6-31G(d,p) level and the geometrical variations among them are discussed. The solvent effect for Sunitinib in aqueous and DMSO phases have been performed by means of the self-consistent recognition reaction field (SCRF) method as implemented in the integral equation formalism polarized continuum model (IEFPCM). On the other hand, NBO analysis has been carried out to understand probable hydrogen bonding sites and charge transfers. Additionally, the HOMO and the LUMO energies are calculated using B3LYP/6-31G(d,p) to determine the intra molecular charge transfers (ICT) within the molecule and the kinetic stabilities for each phases. The molecular electrostatic potential surface (MESP) has been plotted over the optimized structure to estimate the reactive sites of electrophilic and nucleophilic attacks regarding Sunitinib molecule. The potential energy distribution (PED) has been calculated using VEDA4 program and vibrational assignments of the experimental spectra (IR & Raman) have been elucidated by means of the calculated vibrational spectra. The observed vibrational spectra of Sunitinib is compared with the calculated spectra obtained by using B3LYP functional both with 6-31G(d,p) and 6-311++G(d,p) basis sets. Theoretical results

Isospin asymmetry dependence of the α spectroscopic factor for heavy nuclei

International Nuclear Information System (INIS)

Seif, W. M.; Shalaby, M.; Alrakshy, M. F.

2011-01-01

Both the valence nucleons (holes) and the isospin asymmetry dependencies of the preformation probability of an α-cluster inside parents radioactive nuclei are investigated. The calculations are employed in the framework of the density-dependent cluster model of an α-decay process for the even-even spherical parents nuclei with protons number around the closed shell Z 0 = 82 and neutrons number around the closed shells Z 0 = 82 and Z 0 = 126. The microscopic α-daughter nuclear interaction potential is calculated in the framework of the Hamiltonian energy density approach based on the SLy4 Skyrme-like effective interaction. Also, the calculations based on the realistic effective M3Y-Paris nucleon-nucleon force have been used to confirm the results. The calculations then proceed to find the assault frequency and the α penetration probability within the WKB approximation. The half-lives of the different mentioned α decays are then determined and have been used in turn to find the α spectroscopic factor. We found that the spectroscopic factor increases with increasing the isospin asymmetry of the parent nuclei if they have valence protons and neutrons. When the parent nuclei have neutron or proton holes in addition to the valence protons or neutrons, then the spectroscopic factor is found to decrease with increasing isospin asymmetry. The obtained results show also that the deduced spectroscopic factors follow individual linear behaviors as a function of the multiplication of the valence proton (N p ) and neutron (N n ) numbers. These linear dependencies are correlated with the closed shells core (Z 0 ,N 0 ). The same individual linear behaviors are obtained as a function of the multiplication of N p N n and the isospin asymmetry parameter, N p N n I. Moreover, the whole deduced spectroscopic factors are found to exhibit a nearly general linear trend with the function N p N n /(Z 0 +N 0 ).

Spectroscopic diagnostics and measurements at Jet

International Nuclear Information System (INIS)

Giannella, R.

1994-01-01

A concise review is presented of activity in the field spectroscopic diagnostic at JET during the latest few years. Together with a description of instruments, examples are given of the measurements conducted with these systems and some experimental result obtained with such activity are outlined. Emphasis is also given to the upgrading of existing apparatuses and the construction of new diagnostics ahead of the next experimental phase. 48 refs., 5 figs

Cosmic homogeneity: a spectroscopic and model-independent measurement

Science.gov (United States)

Gonçalves, R. S.; Carvalho, G. C.; Bengaly, C. A. P., Jr.; Carvalho, J. C.; Bernui, A.; Alcaniz, J. S.; Maartens, R.

2018-03-01

Cosmology relies on the Cosmological Principle, i.e. the hypothesis that the Universe is homogeneous and isotropic on large scales. This implies in particular that the counts of galaxies should approach a homogeneous scaling with volume at sufficiently large scales. Testing homogeneity is crucial to obtain a correct interpretation of the physical assumptions underlying the current cosmic acceleration and structure formation of the Universe. In this letter, we use the Baryon Oscillation Spectroscopic Survey to make the first spectroscopic and model-independent measurements of the angular homogeneity scale θh. Applying four statistical estimators, we show that the angular distribution of galaxies in the range 0.46 < z < 0.62 is consistent with homogeneity at large scales, and that θh varies with redshift, indicating a smoother Universe in the past. These results are in agreement with the foundations of the standard cosmological paradigm.

Biodegradable starch-based films containing saturated fatty acids: thermal, infrared and raman spectroscopic characterization

Directory of Open Access Journals (Sweden)

Marcelo M. Nobrega

Full Text Available Biodegradable films of thermoplastic starch and poly (butylene adipate co-terephthalate (PBAT containing fatty acids were characterized thermally and with infrared and Raman spectroscopies. The symmetrical character of the benzene ring in PBAT provided a means to illustrate the difference between these spectroscopic techniques, because a band appeared in the Raman spectrum but not in the infrared. The thermal analysis showed three degradation stages related to fatty acids, starch and PBAT. The incorporation of saturated fatty acids with different molecular mass (caproic, lauric and stearic did not change the nature of the chemical bonds among the components in the blends of starch, PBAT and glycerol, according to the thermal analysis, infrared and Raman spectroscopies.

A Fully Customized Baseline Removal Framework for Spectroscopic Applications.

Science.gov (United States)

Giguere, Stephen; Boucher, Thomas; Carey, C J; Mahadevan, Sridhar; Dyar, M Darby

2017-07-01

The task of proper baseline or continuum removal is common to nearly all types of spectroscopy. Its goal is to remove any portion of a signal that is irrelevant to features of interest while preserving any predictive information. Despite the importance of baseline removal, median or guessed default parameters are commonly employed, often using commercially available software supplied with instruments. Several published baseline removal algorithms have been shown to be useful for particular spectroscopic applications but their generalizability is ambiguous. The new Custom Baseline Removal (Custom BLR) method presented here generalizes the problem of baseline removal by combining operations from previously proposed methods to synthesize new correction algorithms. It creates novel methods for each technique, application, and training set, discovering new algorithms that maximize the predictive accuracy of the resulting spectroscopic models. In most cases, these learned methods either match or improve on the performance of the best alternative. Examples of these advantages are shown for three different scenarios: quantification of components in near-infrared spectra of corn and laser-induced breakdown spectroscopy data of rocks, and classification/matching of minerals using Raman spectroscopy. Software to implement this optimization is available from the authors. By removing subjectivity from this commonly encountered task, Custom BLR is a significant step toward completely automatic and general baseline removal in spectroscopic and other applications.

Function of minerals in the natural radioactivity level of Vaigai River sediments, Tamilnadu, India--spectroscopical approach.

Science.gov (United States)

Ramasamy, V; Paramasivam, K; Suresh, G; Jose, M T

2014-01-03

Using Gamma ray and Fourier Transform Infrared (FTIR) spectroscopic techniques, level of natural radioactivity ((238)U, (232)Th and (40)K) and mineralogical characterization of Vaigai River sediments have been analyzed with the view of evaluating the radiation risk and its relation to available minerals. Different radiological parameters are calculated to know the entire radiological characterization. The average of activity concentrations and all radiological parameters are lower than the recommended safety limit. However, some sites are having higher radioactivity values than the safety limit. From the FTIR spectroscopic technique, the minerals such as quartz, microcline feldspar, orthoclase feldspar, kaolinite, gibbsite, calcite, montmorillonite and organic carbon are identified and they are characterized. The extinction co-efficient values are calculated to know the relative distribution of major minerals such as quartz, microcline feldspar, orthoclase feldspar and kaolinite. The calculated values indicate that the amount of quartz is higher than orthoclase feldspar, microcline feldspar and much higher than kaolinite. Crystallinity index is calculated to know the crystalline nature of quartz and the result indicates that the presence of ordered crystalline quartz in the present sediment. The role of minerals in the level of radioactivity is assessed by multivariate statistical analysis (Pearson's correlation and Cluster analysis). The statistical analysis confirms that the clay mineral kaolinite is the major factor than other major minerals to induce the important radioactivity variables such as absorbed dose rate and concentrations of (232)Th and (238)U. Copyright © 2013 Elsevier B.V. All rights reserved.

Influence of the matrix composition in the Emission spectroscopic analysis of solutions with continuous nebulization of the sample and excitation of the spectrum in a high-frequency inductively coupled plasma discharge

International Nuclear Information System (INIS)

Zil'bershtein, K.I.; Kartasheva, M.A.; Mushkovich, G.N.

1986-01-01

Numerous investigations have shown that the emission spectroscopic analysis of solutions with the use of a high-frequency inductively coupled plasma discharge is characterized by the absence of an influence or the presence of a small influence of the matrix elements on the amplitudes of the analytical signals of the elements being determined and, consequently, on the results of an analysis. The influences of the first type include the influences of easily ionized elements, which, as we know, are very significant in spectroscopic analysis with the use of traditional sources for the excitation of the spectra (arcs, sparks, and flames). The influences of the second type include, in particular, the influences associated with changes in the viscosity and surface tension of the solutions as the concentration of the matrix elements in the solutions is increased. In order to obtain correct results from an analysis in the case of spectral interference, special methods for treating the spectra are used for the purpose of taking into account the background and the instances of superposition and establishing the true (''pure'') intensity of the analytical lines. Results are shown of the Determination of impurities in aqueous solutions of sodium Molybate Single Crystals (the concentration of Na 2 Mo 2 O 7 in the solution was 1 mg/ml). When the solutions being analyzed are diluted to a concentration of Na 2 Mo 2 O 7 equal to 1 mg/ml, good agreement between the results of the determination of vanadium (and other impurities) obtained with the use of reference solutions not containing the matrix elements and the results obtained with the use of reference solutions containing the matrix elements in the same concentrations as in the solutions being analyzed (1mg/ml) was guaranteed

Use of functionalized surfactants in flame atomic analysis: Final technical report

International Nuclear Information System (INIS)

Armstrong, D.W.

1987-01-01

Research results in the following areas are briefly summarized: basic properties of surfactants, micelles, and cyclodextrins as they relate to chemical analysis; use of functionalized surfactants, micelles, and cyclodextrins in spectroscopic analysis; macromolecular separation theory and mechanism; use of functionalized surfactants and cyclodextrins in separations; capillary work for future coupling of spectroscopic and LC projects

Spectroscopic studies of copper doped alkaline earth lead zinc phosphate glasses

Energy Technology Data Exchange (ETDEWEB)

Sastry, S. Sreehari, E-mail: sreeharisastry@yahoo.com [Department of Physics, Acharya Nagarjuna University, Nagarjunanagar 522510 (India); Rao, B. Rupa Venkateswara [Department of Physics, Acharya Nagarjuna University, Nagarjunanagar 522510 (India); Department of Physics, V.R. Siddhartha Engineering College, Vijayawada 52007 (India)

2014-02-01

In this paper spectroscopic investigation of Cu{sup 2+} doped alkaline earth lead zinc phosphate glasses was done through the spectroscopic techniques like X-ray diffraction, Ultra Violet (UV) absorption Spectroscopy, Electron Paramagnetic Resonance (EPR – X band), Fourier Transform Infra Red (FTIR) and Raman Spectroscopy. Alkaline earth lead zinc phosphate glasses containing 0.1% copper oxide (CuO) were prepared by the melt quenching technique. Spectroscopic studies indicated that there is a greater possibility for the copper ions to exist in Cu{sup 2+} state in these glasses. The optical absorption spectra indicated that the absorption peak of Cu{sup 2+} is a function of composition. The maxima absorption peak was reported at 862 nm for strontium lead zinc phosphate glass. Bonding parameters were calculated for the optical and EPR data. All these spectral results indicated clearly that there are certain structural changes in the present glass system with different alkaline earth contents. The IR and Raman spectra noticed the breaking of the P–O–P bonds and creating more number of new P–O–Cu bonds.

Spectroscopic studies of copper doped alkaline earth lead zinc phosphate glasses

International Nuclear Information System (INIS)

Sastry, S. Sreehari; Rao, B. Rupa Venkateswara

2014-01-01

In this paper spectroscopic investigation of Cu 2+ doped alkaline earth lead zinc phosphate glasses was done through the spectroscopic techniques like X-ray diffraction, Ultra Violet (UV) absorption Spectroscopy, Electron Paramagnetic Resonance (EPR – X band), Fourier Transform Infra Red (FTIR) and Raman Spectroscopy. Alkaline earth lead zinc phosphate glasses containing 0.1% copper oxide (CuO) were prepared by the melt quenching technique. Spectroscopic studies indicated that there is a greater possibility for the copper ions to exist in Cu 2+ state in these glasses. The optical absorption spectra indicated that the absorption peak of Cu 2+ is a function of composition. The maxima absorption peak was reported at 862 nm for strontium lead zinc phosphate glass. Bonding parameters were calculated for the optical and EPR data. All these spectral results indicated clearly that there are certain structural changes in the present glass system with different alkaline earth contents. The IR and Raman spectra noticed the breaking of the P–O–P bonds and creating more number of new P–O–Cu bonds

Development of laser atomic spectroscopic technology

International Nuclear Information System (INIS)

Lee, Jong Min; Ohr, Young Gie; Cha, Hyung Ki

1990-06-01

Some preliminary results on the resonant ionization spectroscopy for Na and Pb atoms are presents both in theory and in experiment. A single color multiphoton ionization process is theoretically analysed in detail, for the resonant and non-resonant cases, and several parameters determining the overall ionization rate are summarized. In particular, the AC stark shift, the line width and the non-linear coefficient of ionization rate are recalculated using the perturbation theory in resolvent approach. On the other hand, the fundamental equipments for spectroscopic experiments have been designed and manufactured, which include a Nd:YAG laser, a GIM-type dye laser, a vacuum system ionization cells, a heat pipe oven, and an ion current measuring system. The characteristics of the above equipments have also been examined. Using the spectroscopic data available, several ionization schemes are considered and the relative merits for ionization have been discussed. Moreover, the effects due to the buffer gas pressure, laser intensity, vapor density and electrode voltage have been investigated in detail. The experiments will be extended to multi-color processes with several resonances, and the ultimate goal is to develop a ultrasensitive analytical method for pollutive heavy metal atoms using the resonant ionization spectroscopy. (author)

Infrared Spectroscopic Imaging: The Next Generation

Science.gov (United States)

Bhargava, Rohit

2013-01-01

Infrared (IR) spectroscopic imaging seemingly matured as a technology in the mid-2000s, with commercially successful instrumentation and reports in numerous applications. Recent developments, however, have transformed our understanding of the recorded data, provided capability for new instrumentation, and greatly enhanced the ability to extract more useful information in less time. These developments are summarized here in three broad areas— data recording, interpretation of recorded data, and information extraction—and their critical review is employed to project emerging trends. Overall, the convergence of selected components from hardware, theory, algorithms, and applications is one trend. Instead of similar, general-purpose instrumentation, another trend is likely to be diverse and application-targeted designs of instrumentation driven by emerging component technologies. The recent renaissance in both fundamental science and instrumentation will likely spur investigations at the confluence of conventional spectroscopic analyses and optical physics for improved data interpretation. While chemometrics has dominated data processing, a trend will likely lie in the development of signal processing algorithms to optimally extract spectral and spatial information prior to conventional chemometric analyses. Finally, the sum of these recent advances is likely to provide unprecedented capability in measurement and scientific insight, which will present new opportunities for the applied spectroscopist. PMID:23031693

AN INTERFEROMETRIC AND SPECTROSCOPIC ANALYSIS OF THE MULTIPLE STAR SYSTEM HD 193322

International Nuclear Information System (INIS)

Ten Brummelaar, Theo A.; Farrington, Christopher D.; Schaefer, Gail H.

2011-01-01

The star HD 193322 is a remarkable multiple system of massive stars that lies at the heart of the cluster Collinder 419. Here we report on new spectroscopic observations and radial velocities of the narrow-lined component Ab1 which we use to determine its orbital motion around a close companion Ab2 (P = 312 days) and around a distant third star Aa (P = 35 years). We have also obtained long baseline interferometry of the target in the K' band with the CHARA Array which we use in two ways. First, we combine published speckle interferometric measurements with CHARA separated fringe packet measurements to improve the visual orbit for the wide Aa,Ab binary. Second, we use measurements of the fringe packet from Aa to calibrate the visibility of the fringes of the Ab1,Ab2 binary, and we analyze these fringe visibilities to determine the visual orbit of the close system. The two most massive stars, Aa and Ab1, have masses of approximately 21 and 23 M sun , respectively, and their spectral line broadening indicates that they represent extremes of fast and slow projected rotational velocity, respectively.

Spectroscopic Needs for Imaging Dark Energy Experiments

International Nuclear Information System (INIS)

Newman, Jeffrey A.; Abate, Alexandra; Abdalla, Filipe B.; Allam, Sahar; Allen, Steven W.; Ansari, Reza; Bailey, Stephen; Barkhouse, Wayne A.; Beers, Timothy C.; Blanton, Michael R.; Brodwin, Mark; Brownstein, Joel R.; Brunner, Robert J.; Carrasco-Kind, Matias; Cervantes-Cota, Jorge; Chisari, Nora Elisa; Colless, Matthew; Coupon, Jean; Cunha, Carlos E.; Frye, Brenda L.; Gawiser, Eric J.; Gehrels, Neil; Grady, Kevin; Hagen, Alex; Hall, Patrick B.; Hearin, Andrew P.; Hildebrandt, Hendrik; Hirata, Christopher M.; Ho, Shirley; Huterer, Dragan; Ivezic, Zeljko; Kneib, Jean-Paul; Kruk, Jeffrey W.; Lahav, Ofer; Mandelbaum, Rachel; Matthews, Daniel J.; Miquel, Ramon; Moniez, Marc; Moos, H. W.; Moustakas, John; Papovich, Casey; Peacock, John A.; Rhodes, Jason; Ricol, Jean-Stepane; Sadeh, Iftach; Schmidt, Samuel J.; Stern, Daniel K.; Tyson, J. Anthony; Von der Linden, Anja; Wechsler, Risa H.; Wood-Vasey, W. M.; Zentner, A.

2015-01-01

Ongoing and near-future imaging-based dark energy experiments are critically dependent upon photometric redshifts (a.k.a. photo-z's): i.e., estimates of the redshifts of objects based only on flux information obtained through broad filters. Higher-quality, lower-scatter photo-z's will result in smaller random errors on cosmological parameters; while systematic errors in photometric redshift estimates, if not constrained, may dominate all other uncertainties from these experiments. The desired optimization and calibration is dependent upon spectroscopic measurements for secure redshift information; this is the key application of galaxy spectroscopy for imaging-based dark energy experiments. Hence, to achieve their full potential, imaging-based experiments will require large sets of objects with spectroscopically-determined redshifts, for two purposes: Training: Objects with known redshift are needed to map out the relationship between object color and z (or, equivalently, to determine empirically-calibrated templates describing the rest-frame spectra of the full range of galaxies, which may be used to predict the color-z relation). The ultimate goal of training is to minimize each moment of the distribution of differences between photometric redshift estimates and the true redshifts of objects, making the relationship between them as tight as possible. The larger and more complete our ''training set'' of spectroscopic redshifts is, the smaller the RMS photo-z errors should be, increasing the constraining power of imaging experiments; Requirements: Spectroscopic redshift measurements for ∼30,000 objects over >∼15 widely-separated regions, each at least ∼20 arcmin in diameter, and reaching the faintest objects used in a given experiment, will likely be necessary if photometric redshifts are to be trained and calibrated with conventional techniques. Larger, more complete samples (i.e., with longer exposure times) can improve photo

Mossbauer spectroscopic studies in ferroboron

Science.gov (United States)

Yadav, Ravi Kumar; Govindaraj, R.; Amarendra, G.

2017-05-01

Mossbauer spectroscopic studies have been carried out in a detailed manner on ferroboron in order to understand the local structure and magnetic properties of the system. Evolution of the local structure and magnetic properties of the amorphous and crystalline phases and their thermal stability have been addressed in a detailed manner in this study. Role of bonding between Fe 4s and/or 4p electrons with valence electrons of boron (2s,2p) in influencing the stability and magnetic properties of Fe-B system is elucidated.

The biocompatibility of carbon hydroxyapatite/β-glucan composite for bone tissue engineering studied with Raman and FTIR spectroscopic imaging.

Science.gov (United States)

Sroka-Bartnicka, Anna; Kimber, James A; Borkowski, Leszek; Pawlowska, Marta; Polkowska, Izabela; Kalisz, Grzegorz; Belcarz, Anna; Jozwiak, Krzysztof; Ginalska, Grazyna; Kazarian, Sergei G

2015-10-01

The spectroscopic approaches of FTIR imaging and Raman mapping were applied to the characterisation of a new carbon hydroxyapatite/β-glucan composite developed for bone tissue engineering. The composite is an artificial bone material with an apatite-forming ability for the bone repair process. Rabbit bone samples were tested with an implanted bioactive material for a period of several months. Using spectroscopic and chemometric methods, we were able to determine the presence of amides and phosphates and the distribution of lipid-rich domains in the bone tissue, providing an assessment of the composite's bioactivity. Samples were also imaged in transmission using an infrared microscope combined with a focal plane array detector. CaF2 lenses were also used on the infrared microscope to improve spectral quality by reducing scattering artefacts, improving chemometric analysis. The presence of collagen and lipids at the bone/composite interface confirmed biocompatibility and demonstrate the suitability of FTIR microscopic imaging with lenses in studying these samples. It confirmed that the composite is a very good background for collagen growth and increases collagen maturity with the time of the bone growth process. The results indicate the bioactive and biocompatible properties of this composite and demonstrate how Raman and FTIR spectroscopic imaging have been used as an effective tool for tissue characterisation.

Spectroscopic and thermal characterization of carbon nanotubes functionalized through diazonium salt reduction

International Nuclear Information System (INIS)

Pandurangappa, Malingappa; Ramakrishnappa, Thippeswamy

2010-01-01

Chemical reduction of anthraquinone diazonium chloride (Fast Red AL salt) in presence of hypophosphorous acid and carbon nanotubes results in anthraquinonyl functionalized carbon nanotubes. The surface functionalized moieties have been examined electrochemically by immobilizing them onto the surface of basal plane pyrolytic graphite electrode and studying its voltammetric behaviour. The effect of pH, and scan rate has revealed that the modified species are confined on the electrode surface. The spectroscopic characterization of the modified single walled carbon nanotubes using Fourier transform infrared spectroscopy, X-ray photoemission spectroscopy, thermogravimetric analysis and transmission electron microscopy have revealed that the modifier molecules are covalently bonded on the surface of carbon nanotubes.

Spectroscopic and thermal characterization of carbon nanotubes functionalized through diazonium salt reduction

Energy Technology Data Exchange (ETDEWEB)

Pandurangappa, Malingappa, E-mail: mprangachem@gmail.com [Department of Chemistry, Bangalore University, Central College Campus, Dr Ambedkar Veedhi, Bangalore 560 001 (India); Ramakrishnappa, Thippeswamy [Department of Chemistry, Bangalore University, Central College Campus, Dr Ambedkar Veedhi, Bangalore 560 001 (India)

2010-08-01

Chemical reduction of anthraquinone diazonium chloride (Fast Red AL salt) in presence of hypophosphorous acid and carbon nanotubes results in anthraquinonyl functionalized carbon nanotubes. The surface functionalized moieties have been examined electrochemically by immobilizing them onto the surface of basal plane pyrolytic graphite electrode and studying its voltammetric behaviour. The effect of pH, and scan rate has revealed that the modified species are confined on the electrode surface. The spectroscopic characterization of the modified single walled carbon nanotubes using Fourier transform infrared spectroscopy, X-ray photoemission spectroscopy, thermogravimetric analysis and transmission electron microscopy have revealed that the modifier molecules are covalently bonded on the surface of carbon nanotubes.

A spectroscopic study of absorption and emission features of interstellar dust components

International Nuclear Information System (INIS)

Zwet, G.P. van der.

1986-01-01

The spectroscopic properties of silicate interstellar dust grains are the subject of this thesis. The process of accretion and photolysis is simulated in the laboratory by condensing mixtures of gases onto a cold substrate (T ∼ 12 K) in a vacuum chamber and photolyzing these mixtures with a vacuum ultraviolet source. Alternatively, the gas mixtures may be passed through a microwave discharge first, before deposition. The spectroscopic properties of the ices are investigated using ultraviolet, visible and infrared spectroscopy. (Auth.)

Spectroscopic, microscopic, and internal stress analysis in cadmium telluride grown by close-space sublimation

International Nuclear Information System (INIS)

Manciu, Felicia S.; Salazar, Jessica G.; Diaz, Aryzbe; Quinones, Stella A.

2015-01-01

High quality materials with excellent ordered structure are needed for developing photovoltaic and infrared devices. With this end in mind, the results of our research prove the importance of a detailed, comprehensive spectroscopic and microscopic analysis in assessing cadmium telluride (CdTe) characteristics. The goal of this work is to examine not only material crystallinity and morphology, but also induced stress in the deposit material. A uniform, selective growth of polycrystalline CdTe by close-space sublimation on patterned Si(111) and Si(211) substrates is demonstrated by scanning electron microscopy images. Besides good crystallinity of the samples, as revealed by both Raman scattering and Fourier transform infrared absorption investigations, the far-infrared transmission data also show the presence of surface optical phonon modes, which is direct evidence of confinement in such a material. The qualitative identification of the induced stress was achieved by performing confocal Raman mapping microscopy on sample surfaces and by monitoring the existence of the rock-salt and zinc-blende structural phases of CdTe, which were associated with strained and unstrained morphologies, respectively. Although the induced stress in the material is still largely due to the high lattice mismatch between CdTe and the Si substrate, the current results provide a direct visualization of its partial release through the relaxation effect at crystallite boundaries and of preferential growth directions of less strain. Our study, thus offers significant value for improvement of material properties, by targeting the needed adjustments in the growth processes. - Highlights: • Assessing the characteristics of CdTe deposited on patterned Si substrates • Proving the utility of confocal Raman microscopy in monitoring the induced stress • Confirming the partial stress release through the grain boundary relaxation effect • Demonstrating the phonon confinement effect in low

Scalar and configuration traces of operators in large spectroscopic spaces

International Nuclear Information System (INIS)

Chang, B.D.; Wong, S.S.M.

1978-01-01

In statistical spectroscopic calculations, the primary input is the trace of products of powers of Hamiltonian and excitation operators. The lack of a systematic approach to trace evaluation has been in the past one of the major difficulties in the applications of statistical spectroscopic methods. A general method with a simple derivation is described here to evaluate the scalar and configuration traces for operators expressed either in the m-scheme or fully coupled JT scheme. It is shown to be an effective method by actually programming it on a computer. Implications on the future applications of statistical spectroscopy in the area of level density, strength function and perturbation theory are also briefly discussed. (Auth.)

The Spectroscopic and Conductive Properties of Ru(II Complexes with Potential Anticancer Properties

Directory of Open Access Journals (Sweden)

Adebayo A. Adeniyi

2014-01-01

Full Text Available Different density functional methods (DFT have been used to optimize and study the chemistry of five potential anticancer complexes in terms of their electronic, conductive, and spectroscopic properties. Many of the computed properties in addition to the IR and QTAIM analysis of the NMR are dipole moment vector (μi, linear polarizability tensor (αij, first hyperpolarizability tensors (βijk, polarizability exaltation index (Γ, and chemical hardness (η of the complexes. Stable low energy geometries are obtained using basis set with effective core potential (ECP approximation but, in the computation of atomic or molecular properties, the metal Ru atom is better treated with higher all electron basis set like DGDZVP. The spectroscopic features like the IR of the metal-ligand bonds and the isotropic NMR shielding tensor of the coordinated atoms are significantly influenced by the chemical environment of the participating atoms. The carboxylic and pyrazole units are found to significantly enhance the polarizabilities and hyperpolarizabilities of the complexes while the chloride only improves the polarity of the complexes. Fermi contacts (FC have the highest effect followed by the PSO among all the four Ramsey terms which defined the total spin-spin coupling constant J (HZ of these complexes.

Mixture analysis by long-range J-resolved 2D NMR

International Nuclear Information System (INIS)

Ha, S.T.K.; Lee, R.W.K.; Wilkins, C.L.

1987-01-01

In most spectroscopic qualitative analyses chromatographic separations are done before identification. Unfortunately, this general approach has suffered from a number of shortcomings. Off-line chromatographic separation followed by spectroscopic analysis is time consuming and inefficient and on-line analysis suffers from mismatch of the material flow requirements between chromatographic columns and spectroscopic instruments. An alternative mixture identification procedure solely based upon use of edited 13 C NMR spectra and a 13 C NMR chemical shift data base is reported. This approach has been demonstrated in the analyses of several mixtures, including a mixture of amino acids and some isomers. In all cases, identifications of components of these mixtures are successful

Spectroscopic analysis of bones for forensic studies

Energy Technology Data Exchange (ETDEWEB)

Tofanelli, Mirko [Applied and Laser Spectroscopy Laboratory, Institute of Chemistry of Organometallic Compounds, Research Area of CNR, Via G. Moruzzi, 1, 56124 Pisa (Italy); Pardini, Lorenzo [Institut für Physik und IRIS Adlershof, Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, 12489 Berlin (Germany); Borrini, Matteo [Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, Byrom Street, Liverpool (United Kingdom); Bartoli, Fulvio; Bacci, Alessandra [Department of Biology, University of Pisa, Via A. Volta, 4, 56126 Pisa (Italy); D’Ulivo, Alessandro; Pitzalis, Emanuela; Mascherpa, Marco Carlo; Legnaioli, Stefano; Lorenzetti, Giulia; Pagnotta, Stefano [Applied and Laser Spectroscopy Laboratory, Institute of Chemistry of Organometallic Compounds, Research Area of CNR, Via G. Moruzzi, 1, 56124 Pisa (Italy); Holanda Cavalcanti, Gildo de [Instituto de Fìsica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza, s/no Campus da Praia Vermelha, CEP 24210-346, Niterói, Rio de Janeiro (Brazil); Lezzerini, Marco [Department of Earth Sciences, University of Pisa, Via Santa Maria, 53, 56126 Pisa (Italy); Palleschi, Vincenzo, E-mail: vincenzo.palleschi@cnr.it [Applied and Laser Spectroscopy Laboratory, Institute of Chemistry of Organometallic Compounds, Research Area of CNR, Via G. Moruzzi, 1, 56124 Pisa (Italy)

2014-09-01

The elemental analysis of human bones can give information about the dietary habits of the deceased, especially in the last years of their lives, which can be useful for forensic studies. The most important requirement that must be satisfied for this kind of analysis is that the concentrations of analyzed elements are the same as ante mortem. In this work, a set of bones was analyzed using Laser-Induced Breakdown Spectroscopy (LIBS) and validated using Inductively Coupled Plasma–Optical Emission Spectroscopy (ICP-OES), in order to compare those two techniques and to investigate the effect of possible alterations in the elemental concentrations' proportion resulting from the treatment usually applied for preparing the bones for traditional forensic analysis. The possibility that elemental concentrations' changes would occur after accidental or intentional burning of the bones was also studied. - Highlights: • The LIBS analysis of (animal) bones is presented, to establish its feasibility for forensic studies. • Untreated bones and bones subjected to high temperatures (boiled, burned) were analyzed. • A simple calibration, using a single reference sample, gave reasonable quantitative results. • The comparison of the results demonstrates that LIBS analysis can provide nutritional information. • The nutritional information obtained are the same on untreated, boiled and burned bones.

Spectroscopic analysis of bones for forensic studies

International Nuclear Information System (INIS)

Tofanelli, Mirko; Pardini, Lorenzo; Borrini, Matteo; Bartoli, Fulvio; Bacci, Alessandra; D’Ulivo, Alessandro; Pitzalis, Emanuela; Mascherpa, Marco Carlo; Legnaioli, Stefano; Lorenzetti, Giulia; Pagnotta, Stefano; Holanda Cavalcanti, Gildo de; Lezzerini, Marco; Palleschi, Vincenzo

2014-01-01

The elemental analysis of human bones can give information about the dietary habits of the deceased, especially in the last years of their lives, which can be useful for forensic studies. The most important requirement that must be satisfied for this kind of analysis is that the concentrations of analyzed elements are the same as ante mortem. In this work, a set of bones was analyzed using Laser-Induced Breakdown Spectroscopy (LIBS) and validated using Inductively Coupled Plasma–Optical Emission Spectroscopy (ICP-OES), in order to compare those two techniques and to investigate the effect of possible alterations in the elemental concentrations' proportion resulting from the treatment usually applied for preparing the bones for traditional forensic analysis. The possibility that elemental concentrations' changes would occur after accidental or intentional burning of the bones was also studied. - Highlights: • The LIBS analysis of (animal) bones is presented, to establish its feasibility for forensic studies. • Untreated bones and bones subjected to high temperatures (boiled, burned) were analyzed. • A simple calibration, using a single reference sample, gave reasonable quantitative results. • The comparison of the results demonstrates that LIBS analysis can provide nutritional information. • The nutritional information obtained are the same on untreated, boiled and burned bones

Raman spectroscopic study of some chalcopyrite-xanthate flotation products

CSIR Research Space (South Africa)

Andreev, GN

2003-12-16

Full Text Available of normal vibrations of the corresponding individual compounds. The latter facilitated the Raman spectroscopic elucidation of the reaction products formed on the chalcopyrite surface in real industrial flotation conditions with a sodium isopropyl xanthate...

A Speckle survey of Southern Hipparcos Visual Doubles and Geneva-Copenhagen Spectroscopic Binaries

Science.gov (United States)

Mendez, R. A.; Tokovinin, A.; Horch, E.

2018-01-01

We present a speckle survey of Hipparcos visual doubles and spectroscopic binary stars identified by the Geneva-Copenhagen spectroscopic survey with the SOAR 4m telescope + HRCam. These systems represent our best chance to take advantage of Gaia parallaxes for the purpose of stellar mass determinations. Many of these systems already have mass fractions (although generally no spectroscopic orbit - an astrometric orbit will determine individual masses), metallicity information, and Hipparcos distances. They will be used to improve our knowledge of the mass-luminosity relation, particularly for lower-metallicity stars. Our survey will create the first all-sky, volume-limited, speckle archive for the two primary samples, complementing a similar effort that has been recently been completed at the WIYN 3.5-m telescope in the Northern Hemisphere. This extension to the Southern Hemisphere will fill out the picture for a wider metallicity range.

Spectroscopic ellipsometry analysis of InGaN/GaN and AlGaN/GaN heterostructures using a parametric dielectric function model

International Nuclear Information System (INIS)

Wagner, J.; Ramakrishnan, A.; Obloh, H.; Kunzer, M.; Koehler, K.; Johs, B.

2000-01-01

Spectroscopic ellipsometry (SE) has been used for the characterization of AlGaN/GaN and InGaN/GaN heterostructures. The resulting pseudodielectric function spectra were analyzed using a multilayer approach, describing the dielectric functions of the individual layers by a parametric oscillator model. From this analysis, the dielectric function spectra of GaN, Al x Ga 1-x N (x le 0.16), and In 0.13 Ga 0.87 N were deduced. Further, the dependence of the Al x Ga 1-x N band gap energy on the Al mole fraction was derived and compared with photoluminescence data recorded on the same material. The SE band gap data are compatible with a bowing parameter close to 1 eV for the composition dependence of the Al x Ga 1-x N gap energy. Finally, the parametric dielectric functions have been used to model the pseudodielectric function spectrum of a complete GaN/AlGaN/InGaN LED structure

An extensive spectroscopic time series of three Wolf-Rayet stars - I. The lifetime of large-scale structures in the wind of WR 134

Czech Academy of Sciences Publication Activity Database

Aldoretta, E.J.; St-Louis, N.; Richardson, N.; Moffat, A.F.J.; Eversberg, T.; Hill, G.M.; Shenar, T.; Artigau, E.; Gauza, B.; Knapen, J.H.; Kubát, Jiří; Kubátová, Brankica; Maltais-Tariant, R.; Munoz, M.; Pablo, H.; Ramiaramanantsoa, T.; Richard-Laferriere, A.; Sablowski, D.P.; Simon-Diaz, S.; St-Jean, L.; Bolduan, F.; Dias, F.M.; Dubreuil, P.; Fuchs, D.; Garrel, T.; Grutzeck, G.; Hunger, T.; Kuesters, D.; Langenbrink, M.; Leadbeater, R.; Li, D.; Lopez, A.; Mauclaire, B.; Moldenhawer, T.; Potter, M.; dos Santos, E.M.; Schanne, L.; Schmidt, J.; Sieske, H.; Strachan, J.; Stinner, E.; Stinner, P.; Stober, B.; Strandbaek, K.; Syder, T.; Verilhac, D.; Waldschlaeger, U.; Weiss, D.; Wendt, A.

2016-01-01

Roč. 460, č. 3 (2016), s. 3407-3417 ISSN 0035-8711 R&D Projects: GA ČR GA13-10589S Institutional support: RVO:67985815 Keywords : instabilities * data analysis * spectroscopic techniques Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.961, year: 2016

Simple preparation of new N-aryl-N-(3-indolmethyl acetamides and their spectroscopic analysis

Directory of Open Access Journals (Sweden)

José A. Henao

2009-12-01

Full Text Available To prepare new indolic molecules and characterize them by spectroscopic methods. Materials and methods: All reagentswere purchased from Aldrich, commercial grade. The purity of the products and the composition of the reaction mixtures were monitoredby thin layer chromatography over Silufol UV254 0.25 mm-thick chromatoplates. Product isolation and purification were performed bycolumn chromatography (SiO2, using ethyl acetate-petroleum ether mixtures as eluents. Results. The synthesis of new N-aryl-N-(3-indolmethyl acetamides based on first step iminization reaction of indol-3-carbaldehyde is accomplished. The structures of the C-3substituted indoles were confirmed by 1H-NMR and 13C-NMR studies supported by inverse-detected 2D NMR experiments and alsothrough monocrystal X-ray diffraction. Conclusions. An efficient, economic, and fast synthetic route was designed to the construction ofthe N-aryl-N-(3-indolmethyl acetamides, structural analogues of some alkaloids.

Spectroscopic and antimicrobial studies of polystyrene films under ...

Indian Academy of Sciences (India)

Spectroscopic and antimicrobial studies of polystyrene films under air plasma and He-Ne laser treatment ... The parameters such as (1) surface area by contact angle measurements, (2) quality of material before and after treatment by SEM and FTIR spectra and (3) material characterization by UV-vis spectra were studied.

THE SDSS-IV EXTENDED BARYON OSCILLATION SPECTROSCOPIC SURVEY: OVERVIEW AND EARLY DATA

Energy Technology Data Exchange (ETDEWEB)

Dawson, Kyle S.; Bautista, Julian E. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Kneib, Jean-Paul [Laboratoire dástrophysique, Ecole Polytechnique Fédérale de Lausanne Observatoire de Sauverny, 1290 Versoix (Switzerland); Percival, Will J. [Institute of Cosmology and Gravitation, Dennis Sciama Building, University of Portsmouth, Portsmouth, PO1 3FX (United Kingdom); Alam, Shadab [Bruce and Astrid McWilliams Center for Cosmology, Department of Physics, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, PA 15213 (United States); Albareti, Franco D. [Instituto de Física Teórica, (UAM/CSIC), Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid (Spain); Anderson, Scott F. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Armengaud, Eric [CEA, Centre de Saclay, Irfu/SPP, F-91191 Gif-sur-Yvette (France); Aubourg, Éric [APC, University of Paris Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cite (France); Bailey, Stephen; Beutler, Florian [Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720 (United States); Berlind, Andreas A. [Department of Physics and Astronomy, Vanderbilt University, PMB 401807, 2401 Vanderbilt Place, Nashville, TN 37240 (United States); Bershady, Matthew A. [University of Wisconsin-Madison, Department of Astronomy, 475 N. Charter St., Madison WI 53703 (United States); Bizyaev, Dmitry [Apache Point Observatory, P.O. Box 59, sunspot, NM 88349 (United States); Blanton, Michael R., E-mail: kdawson@astro.utah.edu [Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); and others

2016-02-15

In a six-year program started in 2014 July, the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) will conduct novel cosmological observations using the BOSS spectrograph at Apache Point Observatory. These observations will be conducted simultaneously with the Time Domain Spectroscopic Survey (TDSS) designed for variability studies and the Spectroscopic Identification of eROSITA Sources (SPIDERS) program designed for studies of X-ray sources. In particular, eBOSS will measure with percent-level precision the distance-redshift relation with baryon acoustic oscillations (BAO) in the clustering of matter. eBOSS will use four different tracers of the underlying matter density field to vastly expand the volume covered by BOSS and map the large-scale-structures over the relatively unconstrained redshift range 0.6 < z < 2.2. Using more than 250,000 new, spectroscopically confirmed luminous red galaxies at a median redshift z = 0.72, we project that eBOSS will yield measurements of the angular diameter distance d{sub A}(z) to an accuracy of 1.2% and measurements of H(z) to 2.1% when combined with the z > 0.6 sample of BOSS galaxies. With ∼195,000 new emission line galaxy redshifts, we expect BAO measurements of d{sub A}(z) to an accuracy of 3.1% and H(z) to 4.7% at an effective redshift of z = 0.87. A sample of more than 500,000 spectroscopically confirmed quasars will provide the first BAO distance measurements over the redshift range 0.9 < z < 2.2, with expected precision of 2.8% and 4.2% on d{sub A}(z) and H(z), respectively. Finally, with 60,000 new quasars and re-observation of 60,000 BOSS quasars, we will obtain new Lyα forest measurements at redshifts z > 2.1; these new data will enhance the precision of d{sub A}(z) and H(z) at z > 2.1 by a factor of 1.44 relative to BOSS. Furthermore, eBOSS will provide improved tests of General Relativity on cosmological scales through redshift-space distortion measurements, improved tests for non

Spectroscopic and structural study of the newly synthesized heteroligand complex of copper with creatinine and urea.

Science.gov (United States)

Gangopadhyay, Debraj; Singh, Sachin Kumar; Sharma, Poornima; Mishra, Hirdyesh; Unnikrishnan, V K; Singh, Bachcha; Singh, Ranjan K

2016-02-05

Study of copper complex of creatinine and urea is very important in life science and medicine. In this paper, spectroscopic and structural study of a newly synthesized heteroligand complex of copper with creatinine and urea has been discussed. Structural studies have been carried out using DFT calculations and spectroscopic analyses were carried out by FT-IR, Raman, UV-vis absorption and fluorescence techniques. The copper complex of creatinine and the heteroligand complex were found to have much increased water solubility as compared to pure creatinine. The analysis of FT-IR and Raman spectra helps to understand the coordination properties of the two ligands and to determine the probable structure of the heteroligand complex. The LIBS spectra of the heteroligand complex reveal that the complex is free from other metal impurities. UV-visible absorption spectra and the fluorescence emission spectra of the aqueous solution of Cu-Crn-urea heteroligand complex at different solute concentrations have been analyzed and the complex is found to be rigid and stable in its monomeric form at very low concentrations. Copyright © 2015 Elsevier B.V. All rights reserved.

Phenomenological and Spectroscopic Analysis on the Effects of Sediment Ageing and Organic Carbon on the Fate of a PCB Congener Spiked to Sediment

Science.gov (United States)

This study assesses the full cycle transport and fate of a polychlorinated biphenyl (PCB) congener spiked to sediment to empirically and spectroscopically investigate the effects of sediment ageing and organic carbon on the adsorption, desorption, and reaction of the PCB. Caesar ...

ITER perspective on fusion reactor diagnostics - A spectroscopic view

DEFF Research Database (Denmark)

De Bock, M. F. M.; Barnsley, R.; Bassan, M.

2016-01-01

challenges to the development of spectroscopic (but also other) diagnostics. This contribution presents an overview of recent achievements in 4 topical areas: First mirror protection and cleaning, Nuclear confinement, Radiation mitigation strategy for optical and electronic components and Calibration...

Spectroscopic and Spectrometric Methods Used for the Screening of Certain Herbal Food Supplements Suspected of Adulteration.

Science.gov (United States)

Mateescu, Cristina; Popescu, Anca Mihaela; Radu, Gabriel Lucian; Onisei, Tatiana; Raducanu, Adina Elena

2017-06-01

Purpose: This study was carried out in order to find a reliable method for the fast detection of adulterated herbal food supplements with sexual enhancement claims. As some herbal products are advertised as "all natural", their "efficiency" is often increased by addition of active pharmaceutical ingredients such as PDE-5 inhibitors, which can be a real health threat for the consumer. Methodes: Adulterants, potentially present in 50 herbal food supplements with sexual improvement claims, were detected using 2 spectroscopic methods - Raman and Fourier Transform Infrared - known for reliability, reproductibility, and an easy sample preparation. GC-MS technique was used to confirm the potential adulterants spectra. Results: About 22% (11 out of 50 samples) of herbal food supplements with sexual enhancement claims analyzed by spectroscopic and spectrometric methods proved to be "enriched" with active pharmaceutical compounds such as: sildenafil and two of its analogues, tadalafil and phenolphthalein. The occurence of phenolphthalein could be the reason for the non-relevant results obtained by FTIR method in some samples. 91% of the adulterated herbal food supplements were originating from China. Conclusion: The results of this screening highlighted the necessity for an accurate analysis of all alleged herbal aphrodisiacs on the Romanian market. This is a first such a screening analysis carried out on herbal food supplements with sexual enhancement claims.

Particle in a Disk: A Spectroscopic and Computational Laboratory Exercise Studying the Polycyclic Aromatic Hydrocarbon Corannulene

Science.gov (United States)

Frey, E. Ramsey; Sygula, Andrzej; Hammer, Nathan I.

2014-01-01

This laboratory exercise introduces undergraduate chemistry majors to the spectroscopic and theoretical study of the polycyclic aromatic hydrocarbon (PAH), corannulene. Students explore the spectroscopic properties of corannulene using UV-vis and Raman vibrational spectroscopies. They compare their experimental results to simulated vibrational…

Detection of spectroscopic binaries in the Gaia-ESO Survey

Science.gov (United States)

Van der Swaelmen, M.; Merle, T.; Van Eck, S.; Jorissen, A.

2017-12-01

The Gaia-ESO survey (GES) is a ground-based spectroscopic survey, complementing the Gaia mission, in order to obtain high accuracy radial velocities and chemical abundances for 10^5 stars. Thanks to the numerous spectra collected by the GES, the detection of spectroscopic multiple system candidates (SBn, n ≥ 2) is one of the science case that can be tackled. We developed at IAA (Institut d'Astronomie et d'Astrophysique) a novative automatic method to detect multiple components from the cross-correlation function (CCF) of spectra and applied it to the CCFs provided by the GES. Since the bulk of the Milky Way field targets has been observed in both HR10 and HR21 GIRAFFE settings, we are also able to compare the efficiency of our SB detection tool depending on the wavelength range. In particular, we show that HR21 leads to a less efficient detection compared to HR10. The presence of strong and/or saturated lines (Ca II triplet, Mg I line, Paschen lines) in the wavelength domain covered by HR21 hampers the computation of CCFs, which tend to be broadened compared to their HR10 counterpart. The main drawback is that the minimal detectable radial velocity difference is ˜ \\SI{60}km/s for HR21 while it is ˜ \\SI{25}km/s for HR10. A careful design of CCF masks (especially masking Ca triplet lines) can substantially improve the detectability rate of HR21. Since HR21 spectra are quite similar to the one produced by the RVS spectrograph of the Gaia mission, analysis of RVS spectra in the context of spectroscpic binaries can take adavantage of the lessons learned from the GES to maximize the detection rate.

A FIVE-YEAR SPECTROSCOPIC AND PHOTOMETRIC CAMPAIGN ON THE PROTOTYPICAL α CYGNI VARIABLE AND A-TYPE SUPERGIANT STAR DENEB

International Nuclear Information System (INIS)

Richardson, N. D.; Morrison, N. D.; Kryukova, E. E.; Adelman, S. J.

2011-01-01

Deneb is often considered the prototypical A-type supergiant and is one of the visually most luminous stars in the Galaxy. A-type supergiants are potential extragalactic distance indicators, but the variability of these stars needs to be better characterized before this technique can be considered reliable. We analyzed 339 high-resolution echelle spectra of Deneb obtained over the five-year span of 1997 through 2001 as well as 370 Stroemgren photometric measurements obtained during the same time frame. Our spectroscopic analysis included dynamical spectra of the Hα profile, Hα equivalent widths, and radial velocities measured from Si II λλ 6347, 6371. Time-series analysis reveals no obvious cyclic behavior that proceeds through multiple observing seasons, although we found a suspected 40 day period in two, non-consecutive observing seasons. Some correlations are found between photometric and radial velocity data sets and suggest radial pulsations at two epochs. No correlation is found between the variability of the Hα profiles and that of the radial velocities or the photometry. Lucy found evidence that Deneb was a long-period single-lined spectroscopic binary star, but our data set shows no evidence for radial velocity variations caused by a binary companion.

Immunocytochemistry by electron spectroscopic imaging using a homogeneously boronated peptide.

Science.gov (United States)

Kessels, M M; Qualmann, B; Klobasa, F; Sierralta, W D

1996-05-01

A linear all-L-oligopeptide containing five carboranyl amino acids (corresponding to 50 boron atoms) was synthesized and specifically attached to the free thiol group of monovalent antibody fragments F(ab)'. The boronated immunoreagent was used for the direct post-embedding detection of somatotrophic hormone in ultrathin sections of porcine pituitary embedded in Spurr resin. The specific boron-labelling of secretory vesicles in somatotrophs was detected by electron spectroscopic imaging and confirmed by conventional immunogold labelling run in parallel. In comparison with immunogold, boron-labelled F(ab)'-fragments showed higher tagging frequencies, as was expected; the small uncharged immunoreagents have an elongated shape and carry the antigen-combining structure and the detection tag at opposite ends, thus allowing for high spatial resolution in electron spectroscopic imaging.

Study of transfer reactions (α,t), (α,3He) in the f-p shell: mechanism and spectroscopic use

International Nuclear Information System (INIS)

Roussel, P.

1968-05-01

We describe an experimental study of (α,t), (α, 3 He) reactions at 44 MeV using a solid-state identifier, on the target-nuclei 54 Fe and 58,60,62,64 Ni. A critical study of optical model and of disturbed wave analysis has been performed. We show the complementarity of different transfer-reactions, the ambiguity of spectroscopic factors, the importance of the problem of the reaction mechanism. (author) [fr

An approach to the analysis of SDSS spectroscopic outliers based on self-organizing maps. Designing the outlier analysis software package for the next Gaia survey

Science.gov (United States)

Fustes, D.; Manteiga, M.; Dafonte, C.; Arcay, B.; Ulla, A.; Smith, K.; Borrachero, R.; Sordo, R.

2013-11-01

Aims: A new method applied to the segmentation and further analysis of the outliers resulting from the classification of astronomical objects in large databases is discussed. The method is being used in the framework of the Gaia satellite Data Processing and Analysis Consortium (DPAC) activities to prepare automated software tools that will be used to derive basic astrophysical information that is to be included in final Gaia archive. Methods: Our algorithm has been tested by means of simulated Gaia spectrophotometry, which is based on SDSS observations and theoretical spectral libraries covering a wide sample of astronomical objects. Self-organizing maps networks are used to organize the information in clusters of objects, as homogeneously as possible according to their spectral energy distributions, and to project them onto a 2D grid where the data structure can be visualized. Results: We demonstrate the usefulness of the method by analyzing the spectra that were rejected by the SDSS spectroscopic classification pipeline and thus classified as "UNKNOWN". First, our method can help distinguish between astrophysical objects and instrumental artifacts. Additionally, the application of our algorithm to SDSS objects of unknown nature has allowed us to identify classes of objects with similar astrophysical natures. In addition, the method allows for the potential discovery of hundreds of new objects, such as white dwarfs and quasars. Therefore, the proposed method is shown to be very promising for data exploration and knowledge discovery in very large astronomical databases, such as the archive from the upcoming Gaia mission.

Electrochemical and spectroscopic studies of uranium(IV), -(V), and -(VI) in carbonate-bicarbonate buffers

International Nuclear Information System (INIS)

Wester, D.W.; Sullivan, J.C.

1980-01-01

Recently a need for more detailed knowledge of the chemistry of actinide ions in basic media has arisen in connection with deducing their chemistry in the environment. In this work the results of polarographic, cyclic voltammetric, and spectroscopic studies of U(IV), -(V), and -(VI) in carbonate and bicarbonate media are reported. Polarographic studies were in excellent agreement with those reported previously. Cyclic voltammetric scans confirmed the irreversible reduction to U(V) in both solutions, but disproportionation of the U(V) was observed only in the bicarbonate solutions. The oxidation of U(V) in carbonate was followed spectroscopically for the first time. Reduction in bicarbonate produced U(IV), the spectrum of which is now reported and the oxidation of which was also followed spectroscopically for the first time

Spectroscopic investigation of the pH controlled inclusion of doxycycline and oxytetracycline antibiotics in cationic micelles and their magnesium driven release.

Science.gov (United States)

Cesaretti, Alessio; Carlotti, Benedetta; Gentili, Pier Luigi; Clementi, Catia; Germani, Raimondo; Elisei, Fausto

2014-07-24

This work presents a steady-state and time-resolved UV-visible spectroscopic investigation of two antibiotics belonging to the family of tetracyclines (doxycycline and oxytetracycline) in the micellar medium provided by p-dodecyloxybenzyltrimethylammonium bromide (pDoTABr). The spectroscopic analysis has been performed in absorption and emission with femtosecond time resolution, and at pH 5.0 and 8.7 where doxycycline and oxytetracycline are present in their neutral-zwitterionic and monoanionic forms, respectively. The experimental data have been processed by sophisticated data mining methods such as global/target analysis and the maximum entropy method. The results unambiguously indicate that, when doxycycline and oxytetracycline are in their zwitterionic form, they are entrapped within the micelle, while when they are in their monoanionic form, they preferentially show a strong one-to-one interaction with the positively charged surfactant heads. Thus, the pH of the solution controls the inclusion of the investigated drugs into the micelle. When the drugs are entrapped inside the micelles, their spectroscopic and dynamical properties after photoexcitation change appreciably. Interestingly, the entrapped drugs are still able to strongly bind Mg(2+) cations, crucial in determining the biological functioning of tetracyclines. The femtosecond resolved measurements reveal that the drugs are efficiently pulled out of the micelles by Mg(2+). In fact, magnesium-tetracycline complexes are detected in the aqueous phase. The present study suggests the potential promising use of ammonium surfactant micelles embedding doxycycline and oxytetracycline as "smart" drug delivery systems allowing their pH controlled inclusion and Mg(2+) induced release.

Syntheses and spectroscopic properties of mercury(II) and nickel(II ...

African Journals Online (AJOL)

Syntheses and spectroscopic properties of mercury(II) and nickel(II) ... The complexes were characterized by IR, diffuse reflectance, 1H NMR spectra and elemental ... coordinating through thiolato sulphur and hydrazinic nitrogen atoms.

A spectroscopic transfer standard for accurate atmospheric CO measurements

Science.gov (United States)

Nwaboh, Javis A.; Li, Gang; Serdyukov, Anton; Werhahn, Olav; Ebert, Volker

2016-04-01

Atmospheric carbon monoxide (CO) is a precursor of essential climate variables and has an indirect effect for enhancing global warming. Accurate and reliable measurements of atmospheric CO concentration are becoming indispensable. WMO-GAW reports states a compatibility goal of ±2 ppb for atmospheric CO concentration measurements. Therefore, the EMRP-HIGHGAS (European metrology research program - high-impact greenhouse gases) project aims at developing spectroscopic transfer standards for CO concentration measurements to meet this goal. A spectroscopic transfer standard would provide results that are directly traceable to the SI, can be very useful for calibration of devices operating in the field, and could complement classical gas standards in the field where calibration gas mixtures in bottles often are not accurate, available or stable enough [1][2]. Here, we present our new direct tunable diode laser absorption spectroscopy (dTDLAS) sensor capable of performing absolute ("calibration free") CO concentration measurements, and being operated as a spectroscopic transfer standard. To achieve the compatibility goal stated by WMO for CO concentration measurements and ensure the traceability of the final concentration results, traceable spectral line data especially line intensities with appropriate uncertainties are needed. Therefore, we utilize our new high-resolution Fourier-transform infrared (FTIR) spectroscopy CO line data for the 2-0 band, with significantly reduced uncertainties, for the dTDLAS data evaluation. Further, we demonstrate the capability of our sensor for atmospheric CO measurements, discuss uncertainty calculation following the guide to the expression of uncertainty in measurement (GUM) principles and show that CO concentrations derived using the sensor, based on the TILSAM (traceable infrared laser spectroscopic amount fraction measurement) method, are in excellent agreement with gravimetric values. Acknowledgement Parts of this work have been

Spectroscopic analysis and dosimetry of diagnostic x-ray beams filtered by rare earth materials

International Nuclear Information System (INIS)

Tyndall, D.A.

1986-01-01

A laboratory investigation was carried out to assess the effect of various types of rare earth filter materials on the energy spectrum and concomitant reduced exposure values of diagnostic x-ray beams at 70, 80, and 90 kVp. An x-ray spectroscope was constructed and used to generate the energy spectra of beams passing through the various rare earth filter materials. Photographs were made of each spectrum, and live-time gross photon counts were recorded. Following spectral determinations, ionization chamber readings were generated for each filter material. Substantial effects on x-ray spectra and reduction of exposure values were noted. The degree of these effects were dependent on the atomic number, k-edge, and thickness of each filter. Metallic forms of rare earth materials proved to be more effective than the salt forms with erbium offering the greatest potential for reduction in exposures over the range of experimental kilovolt (peak) values

Spectroscopic study of trivalent rare earth ions in calcium nitrate hydrate melt

International Nuclear Information System (INIS)

Fujii, Toshiyuki; Asano, Hideki; Kimura, Takaumi; Yamamoto, Takeshi; Uehara, Akihiro; Yamana, Hajimu

2006-01-01

Influence of the water content to chemical status of trivalent rare earth ions in calcium nitrate hydrate melt was studied by spectroscopic techniques. Fluorescence spectrometry for Eu(III) in Ca(NO 3 ) 2 .RH 2 O and electronic absorption spectrometry for Nd(III) in Ca(NO 3 ) 2 .RH 2 O were performed for analyzing the changing coordination symmetries through the changes in their hypersensitive transitions. Raman spectroscopic study and EXAFS study were performed for Y(NO 3 ) 3 solutions and Y(III) in Ca(NO 3 ) 2 .RH 2 O for analyzing the oxygen bonding to Y(III). Luminescence lifetime study of Eu(III) and Dy(III) in Ca(NO 3 ) 2 .RH 2 O was performed for evaluating the hydration number changes. Results of these spectroscopic studies indicated that, with the decrease of water content (R), the hydration number decreases while the interaction between trivalent rare earth ion and nitrate ion increases. It was also revealed that the symmetry of the coordination sphere gets distorted gradually by this interaction

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

International Nuclear Information System (INIS)

Manso, M.; Carvalho, M.L.

2009-01-01

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

A convolutional neural network to filter artifacts in spectroscopic MRI.

Science.gov (United States)

Gurbani, Saumya S; Schreibmann, Eduard; Maudsley, Andrew A; Cordova, James Scott; Soher, Brian J; Poptani, Harish; Verma, Gaurav; Barker, Peter B; Shim, Hyunsuk; Cooper, Lee A D

2018-03-09

Proton MRSI is a noninvasive modality capable of generating volumetric maps of in vivo tissue metabolism without the need for ionizing radiation or injected contrast agent. Magnetic resonance spectroscopic imaging has been shown to be a viable imaging modality for studying several neuropathologies. However, a key hurdle in the routine clinical adoption of MRSI is the presence of spectral artifacts that can arise from a number of sources, possibly leading to false information. A deep learning model was developed that was capable of identifying and filtering out poor quality spectra. The core of the model used a tiled convolutional neural network that analyzed frequency-domain spectra to detect artifacts. When compared with a panel of MRS experts, our convolutional neural network achieved high sensitivity and specificity with an area under the curve of 0.95. A visualization scheme was implemented to better understand how the convolutional neural network made its judgement on single-voxel or multivoxel MRSI, and the convolutional neural network was embedded into a pipeline capable of producing whole-brain spectroscopic MRI volumes in real time. The fully automated method for assessment of spectral quality provides a valuable tool to support clinical MRSI or spectroscopic MRI studies for use in fields such as adaptive radiation therapy planning. © 2018 International Society for Magnetic Resonance in Medicine.

Lateralisation with magnetic resonance spectroscopic imaging in temporal lobe epilepsy: an evaluation of visual and region-of-interest analysis of metabolite concentration images

Energy Technology Data Exchange (ETDEWEB)

Vikhoff-Baaz, B. [Sahlgrenska University Hospital, Goeteborg (Sweden); Div. of Medical Physics and Biomedical Engineering, Goeteborg Univ. (Sweden); Goeteborg Univ. (Sweden). Dept. of Radiation Physics; Malmgren, K. [Dept. of Neurology, Goeteborg Univ. (Sweden); Joensson, L.; Ekholm, S. [Dept. of Radiology, Goeteborg Univ. (Sweden); Starck, G. [Div. of Medical Physics and Biomedical Engineering, Goeteborg Univ. (Sweden); Ljungberg, M.; Forssell-Aronsson, E. [Goeteborg Univ. (Sweden). Dept. of Radiation Physics; Uvebrant, P. [Dept. of Paediatrics, Goeteborg Univ. (Sweden)

2001-09-01

We carried out spectroscopic imaging (MRSI) on nine consecutive patients with temporal lobe epilepsy being assessed for epilepsy surgery, and nine neurologically healthy, age-matched volunteers. A volume of interest (VOI) was angled along the temporal horns on axial and sagittal images, and symmetrically over the temporal lobes on coronal images. Images showing the concentrations of N-acetylaspartate (NAA) and of choline-containing compounds plus creatine and phosphocreatine (Cho + Cr) were used for lateralisation. We compared assessment by visual inspection and by signal analysis from regions of interest (ROI) in different positions, where side-to-side differences in NAA/(Cho + Cr) ratio were used for lateralisation. The NAA/(Cho + Cr) ratio from the different ROI was also compared with that in the brain stem to assess if the latter could be used as an internal reference, e. g., for identification of bilateral changes. The metabolite concentration images were found useful for lateralisation of temporal lobe abnormalities related to epilepsy. Visual analysis can, with high accuracy, be used routinely. ROI analysis is useful for quantifying changes, giving more quantitative information about spatial distribution and the degree of signal loss. There was a large variation in NAA/(Cho + Cr) values in both patients and volunteers. The brain stem may be used as a reference for identification of bilateral changes. (orig.)

Lateralisation with magnetic resonance spectroscopic imaging in temporal lobe epilepsy: an evaluation of visual and region-of-interest analysis of metabolite concentration images

International Nuclear Information System (INIS)

Vikhoff-Baaz, B.; Joensson, L.; Ekholm, S.; Starck, G.

2001-01-01

We carried out spectroscopic imaging (MRSI) on nine consecutive patients with temporal lobe epilepsy being assessed for epilepsy surgery, and nine neurologically healthy, age-matched volunteers. A volume of interest (VOI) was angled along the temporal horns on axial and sagittal images, and symmetrically over the temporal lobes on coronal images. Images showing the concentrations of N-acetylaspartate (NAA) and of choline-containing compounds plus creatine and phosphocreatine (Cho + Cr) were used for lateralisation. We compared assessment by visual inspection and by signal analysis from regions of interest (ROI) in different positions, where side-to-side differences in NAA/(Cho + Cr) ratio were used for lateralisation. The NAA/(Cho + Cr) ratio from the different ROI was also compared with that in the brain stem to assess if the latter could be used as an internal reference, e. g., for identification of bilateral changes. The metabolite concentration images were found useful for lateralisation of temporal lobe abnormalities related to epilepsy. Visual analysis can, with high accuracy, be used routinely. ROI analysis is useful for quantifying changes, giving more quantitative information about spatial distribution and the degree of signal loss. There was a large variation in NAA/(Cho + Cr) values in both patients and volunteers. The brain stem may be used as a reference for identification of bilateral changes. (orig.)

Application of imaging spectroscopic reflectometry for characterization of gold reduction from organometallic compound by means of plasma jet technology

Energy Technology Data Exchange (ETDEWEB)

Vodák, Jiří, E-mail: jiri.vodak@yahoo.com [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2, 616 69 Brno (Czech Republic); Nečas, David [RG Plasma Technologies, CEITEC Masaryk University, Kamenice 5, 625 00 Brno (Czech Republic); Pavliňák, David [Department of Physical Electronics, Masaryk University, Kotlářská 2, 611 37 Brno (Czech Republic); Macak, Jan M [Center of Materials and Nanotechnologies, Faculty of Chemical Technology, University of Pardubice, Nám. Čs. Legií 565, 530 02 Pardubice (Czech Republic); Řičica, Tomáš; Jambor, Roman [Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 532 10 Pardubice (Czech Republic); Ohlídal, Miloslav [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2, 616 69 Brno (Czech Republic); Institute of Physics, Faculty of Mining and Geology, VŠB – Technical University of Ostrava (Czech Republic)

2017-02-28

Highlights: • Metallic gold is reduced from an organometallic compound layer using a plasma jet. • Imaging spectroscopic reflectometry is used to locate areas with metallic gold. • The results are completed with XPS and optical microscopy observations. - Abstract: This work presents a new application of imaging spectroscopic reflectometry to determine a distribution of metallic gold in a layer of an organogold precursor which was treated by a plasma jet. Gold layers were prepared by spin coating from a solution of the precursor containing a small amount of polyvinylpyrrolidone on a microscopy glass, then they were vacuum dried. A difference between reflectivity of metallic gold and the precursor was utilized by imaging spectroscopic reflectometry to create a map of metallic gold distribution using a newly developed model of the studied sample. The basic principle of the imaging spectroscopic reflectometry is also shown together with the data acquisition principles. XPS measurements and microscopy observations were made to complete the imaging spectroscopic reflectometry results. It is proved that the imaging spectroscopic reflectometry represents a new method for quantitative evaluation of local reduction of metallic components from metaloorganic compounds.

Microscale Syntheses, Reactions, and 1H NMR Spectroscopic Investigations of Square Planar Macrocyclic Tetraamido-N Cu(III) Complexes Relevant to Green Chemistry

Science.gov (United States)

Uffelman, Erich S.; Doherty, Jonathan R.; Schulze, Carl; Burke, Amy L.; Bonnema, Kristen R.; Watson, Tanya T.; Lee, Daniel W., III

2004-01-01

Microscale fusions, description, and spectroscopic analysis of the reactivity of a square planar Cu(III) complex significant to green chemistry, are presented. The experiment also includes nine focal points on which pre-lab and post-lab questions are based, and the final exams reflect the students' comprehension of these and other features of…

Spectroscopic analysis of high protein nigella seeds (Kalonji) using laser-induced breakdown spectroscopy and inductively coupled plasma/optical emission spectroscopy

Science.gov (United States)

Rehan, Imran; Khan, M. Zubair; Ali, Irfan; Rehan, Kamran; Sultana, Sabiha; Shah, Sher

2018-03-01

The spectroscopic analysis of high protein nigella seeds (also called Kalonji) was performed using pulsed nanosecond laser-induced breakdown spectroscopy (LIBS) at 532 nm. The emission spectrum of Kalonji recorded with an LIBS spectrometer exposed the presence of various elements like Al, B, Ba, Ca, Cr, K, P, Mg, Mn, Na, Ni, S, Si, Cu, Fe, Ti, Sn, Sr, and Zn. The plasma parameters (electron temperature and electron density) were estimated using Ca-I spectral lines and their behavior were studied against laser irradiance. The electron temperature and electron density was observed to show an increasing trend in the range of 5802-7849 K, and (1.2-3.9) × 1017 cm- 3, respectively, in the studied irradiance range of (1.2-12.6) × 109 W/cm2. Furthermore, the effect of varying laser energy on the integrated signal intensities was also studied. The quantitative analysis of the detected elements was performed via the calibration curves drawn for all the observed elements through typical samples made in the known concentration in the Kalonji matrix, and by setting the concentration of P as the calibration. The validity of our LIBS findings was verified via comparison of the results with the concentration of every element find in Kalonji using the standard analytical tool like ICP/OES. The results acquired using LIBS and ICP/OES were found in fine harmony. Moreover, limit of detection was measured for toxic metals only.

Some experiences with absorption, phonon Raman, and luminescence spectroscopic probes of crystal structure of f-element compounds

International Nuclear Information System (INIS)

Peterson, J.R.

1992-01-01

Structural information is crucial to the study and understanding of the basic chemical properties of the f elements. X-ray diffraction (XRD) techniques are usually used to obtain crystal structure information. However, the transuranium (5f) elements, because of their radioactivity and limited availability, present problems for standard XRD analysis. For some time now we have been developing and using various spectroscopic probes of crystal structure; an overview of our research in this area is presented here

SPT-GMOS: A GEMINI/GMOS-SOUTH SPECTROSCOPIC SURVEY OF GALAXY CLUSTERS IN THE SPT-SZ SURVEY

International Nuclear Information System (INIS)

Bayliss, M. B.; Ruel, J.; Stubbs, C. W.; Allen, S. W.; Applegate, D. E.; Ashby, M. L. N.; Bautz, M.; Benson, B. A.; Carlstrom, J. E.; Chang, C. L.; Crawford, T. M.; Bleem, L. E.; Bocquet, S.; Brodwin, M.; Capasso, R.; Chiu, I.; Cho, H-M.; Clocchiatti, A.; Crites, A. T.; Haan, T. de

2016-01-01

We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 deg 2 of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W , of [O ii] λλ 3727, 3729 and H- δ , and the 4000 Å break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m ⋆ ). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ∼20% of the full SPT-SZ sample.

SPT-GMOS: A Gemini/GMOS-South Spectroscopic Survey of Galaxy Clusters in the SPT-SZ Survey

Science.gov (United States)

Bayliss, M. B.; Ruel, J.; Stubbs, C. W.; Allen, S. W.; Applegate, D. E.; Ashby, M. L. N.; Bautz, M.; Benson, B. A.; Bleem, L. E.; Bocquet, S.; Brodwin, M.; Capasso, R.; Carlstrom, J. E.; Chang, C. L.; Chiu, I.; Cho, H.-M.; Clocchiatti, A.; Crawford, T. M.; Crites, A. T.; de Haan, T.; Desai, S.; Dietrich, J. P.; Dobbs, M. A.; Doucouliagos, A. N.; Foley, R. J.; Forman, W. R.; Garmire, G. P.; George, E. M.; Gladders, M. D.; Gonzalez, A. H.; Gupta, N.; Halverson, N. W.; Hlavacek-Larrondo, J.; Hoekstra, H.; Holder, G. P.; Holzapfel, W. L.; Hou, Z.; Hrubes, J. D.; Huang, N.; Jones, C.; Keisler, R.; Knox, L.; Lee, A. T.; Leitch, E. M.; von der Linden, A.; Luong-Van, D.; Mantz, A.; Marrone, D. P.; McDonald, M.; McMahon, J. J.; Meyer, S. S.; Mocanu, L. M.; Mohr, J. J.; Murray, S. S.; Padin, S.; Pryke, C.; Rapetti, D.; Reichardt, C. L.; Rest, A.; Ruhl, J. E.; Saliwanchik, B. R.; Saro, A.; Sayre, J. T.; Schaffer, K. K.; Schrabback, T.; Shirokoff, E.; Song, J.; Spieler, H. G.; Stalder, B.; Stanford, S. A.; Staniszewski, Z.; Stark, A. A.; Story, K. T.; Vanderlinde, K.; Vieira, J. D.; Vikhlinin, A.; Williamson, R.; Zenteno, A.

2016-11-01

We present the results of SPT-GMOS, a spectroscopic survey with the Gemini Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of 2500 deg2 of the southern sky using the South Pole Telescope (SPT). Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were performed between 2011 January and 2015 December, yielding spectra with radial velocity measurements for 2595 sources. We identify 2243 of these sources as galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of SPT-SZ galaxy clusters. The primary goal of these observations was to obtain spectra of cluster member galaxies to estimate cluster redshifts and velocity dispersions. We describe the full spectroscopic data set and resulting data products, including galaxy redshifts, cluster redshifts, and velocity dispersions, and measurements of several well-known spectral indices for each galaxy: the equivalent width, W, of [O II] λλ3727, 3729 and H-δ, and the 4000 Å break strength, D4000. We use the spectral indices to classify galaxies by spectral type (i.e., passive, post-starburst, star-forming), and we match the spectra against photometric catalogs to characterize spectroscopically observed cluster members as a function of brightness (relative to m⋆). Finally, we report several new measurements of redshifts for ten bright, strongly lensed background galaxies in the cores of eight galaxy clusters. Combining the SPT-GMOS data set with previous spectroscopic follow-up of SPT-SZ galaxy clusters results in spectroscopic measurements for >100 clusters, or ∼20% of the full SPT-SZ sample.

The DEIMOS 10K Spectroscopic Survey Catalog of the COSMOS Field

Science.gov (United States)

Hasinger, G.; Capak, P.; Salvato, M.; Barger, A. J.; Cowie, L. L.; Faisst, A.; Hemmati, S.; Kakazu, Y.; Kartaltepe, J.; Masters, D.; Mobasher, B.; Nayyeri, H.; Sanders, D.; Scoville, N. Z.; Suh, H.; Steinhardt, C.; Yang, Fengwei

2018-05-01

We present a catalog of 10,718 objects in the COSMOS field, observed through multi-slit spectroscopy with the Deep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck II telescope in the wavelength range ∼5500–9800 Å. The catalog contains 6617 objects with high-quality spectra (two or more spectral features), and 1798 objects with a single spectroscopic feature confirmed by the photometric redshift. For 2024 typically faint objects, we could not obtain reliable redshifts. The objects have been selected from a variety of input catalogs based on multi-wavelength observations in the field, and thus have a diverse selection function, which enables the study of the diversity in the galaxy population. The magnitude distribution of our objects is peaked at I AB ∼ 23 and K AB ∼ 21, with a secondary peak at K AB ∼ 24. We sample a broad redshift distribution in the range 0 0.65 with chance probabilities 10 Mpc. An object-to-object comparison with a multitude of other spectroscopic samples in the same field shows that our DEIMOS sample is among the best in terms of fraction of spectroscopic failures and relative redshift accuracy. We have determined the fraction of spectroscopic blends to about 0.8% in our sample. This is likely a lower limit and at any rate well below the most pessimistic expectations. Interestingly, we find evidence for strong lensing of Lyα background emitters within the slits of 12 of our target galaxies, increasing their apparent density by about a factor of 4. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

Fuel cells: spectroscopic studies in the electrocatalysis of alcohol oxidation

Directory of Open Access Journals (Sweden)

Iwasita Teresa

2002-01-01

Full Text Available Modern spectroscopic methods are useful for elucidating complex electrochemical mechanisms as those occurring during the oxidation of small organic molecules (CH3OH, HCOH, HCOOH. In the present paper it is shown the use of spectroscopic methods to study the oxidation of alcohols on platinum or Pt-based binary electrodes. These reactions are of importance in conexion with the development of anode systems for use in fuel cells. Mass spectrometry and FT infrared spectroscopy allow to establishing the reaction intermediates and products and the dependence of the amount of species on the applied potential. FTIR and scanning tunneling microscopy contribute to understand the effects of the surface structure on the rate of reaction. Examples are presented for methanol and ethanol oxidation at pure and modified Pt catalysts.

Quantum chemical calculations and spectroscopic measurements of spectroscopic and thermodynamic properties of given uranyl complexes in aqueous solutions with possible environmental and industrial applications

Directory of Open Access Journals (Sweden)

Višňak Jakub

2016-01-01

Full Text Available A brief introduction into computational methodology and preliminary results for spectroscopic (excitation energies, vibrational frequencies in ground and excited electronic states and thermodynamic (stability constants, standard enthalpies and entropies of complexation reactions properties of some 1:1, 1:2 and 1:3 uranyl sulphato- and selenato- complexes in aqueos solutions will be given. The relativistic effects are included via Effective Core Potential (ECP, electron correlation via (TDDFT/B3LYP (dispersion interaction corrected and solvation is described via explicit inclusion of one hydration sphere beyond the coordinated water molecules. We acknowledge limits of this approximate description – more accurate calculations (ranging from semi-phenomenological two-component spin-orbit coupling up to four-component Dirac-Coulomb-Breit hamiltonian and Molecular Dynamics simulations are in preparation. The computational results are compared with the experimental results from Time-resolved Laser-induced Fluorescence Spectroscopy (TRLFS and UV-VIS spectroscopic studies (including our original experimental research on this topic. In case of the TRLFS and UV-VIS speciation studies, the problem of complex solution spectra decomposition into individual components is ill-conditioned and hints from theoretical chemistry could be very important. Qualitative agreement between our quantum chemical calculations of the spectroscopic properties and experimental data was achieved. Possible applications for geochemical modelling (e.g. safety studies of nuclear waste repositories, modelling of a future mining site and analytical chemical studies (including natural samples are discussed.

The LAMOST spectroscopic survey of stars in the Kepler field of view: Activity indicators and stellar parameters

Science.gov (United States)

Molenda-Żakowicz, Joanna; Frasca, Antonio; De Cat, Peter; Catanzaro, Giovanni

2017-09-01

We summarize the results of the completed first round of the LAMOST-Kepler project, and describe the status of its on-going second round. As a result of the first round of this project, the atmospheric parameters (Teff, log g, and [Fe/H]), the spectral classification (spectral type and luminosity class), and the radial velocities (RV) have been measured for 51,385 stars. For 4031 stars, we were able to measure the projected rotational velocity, while the minimum detectable v sin i was 120 km s-1. For 8821 stars with more than one observation, we computed the χ-square probability that the detected RV variations have a random occurrence. Finally, we classified 442 stars as chromospherically active on the basis of the analysis of their Hα and Ca II-IRT fluxes. All our results have been obtained from the low-resolution (R ˜ 1800) spectroscopic observations acquired with the LAMOST instrument. Based on observations collected with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) located at the Xinglong Observatory, China.

FTIR spectroscopic studies of bacterial cellular responses to environmental factors, plant-bacterial interactions and signalling

OpenAIRE

Kamnev, Alexander A.

2008-01-01

Modern spectroscopic techniques are highly useful in studying diverse processes in microbial cells related to or incited by environmental factors. Spectroscopic data for whole cells, supramolecular structures or isolated cellular constituents can reflect structural and/or compositional changes occurring in the course of cellular metabolic responses to the effects of pollutants, environmental conditions (stress factors); nutrients, signalling molecules (communication factors), etc. This inform...

Diffuse reflectance infrared fourier transform spectroscopic (DRIFTS) investigation of E.coli, Staphylococcus aureus and Candida albicans

Digital Repository Service at National Institute of Oceanography (India)

DeSouza, L.; PrabhaDevi; Kamat, T.; Naik, C.G.

-quadrant streak pattern. Sample preparation and DRIFT spectroscopic analysis A single colony of culture cells in replicates of 5, were carefully removed from the fourth quadrant using a platinum loop. The cells were transferred into sterile glass vials... and dried in an incubator at 45°C for 30 min. Special care was taken to free samples completely from moisture by vacuum treatment using a Jouan lyophilizer (RC10-22, Heto DRYWINNER, France). Microbial cells weighing 0.9-1.3 mg dry weight was thoroughly...

Accurate spectroscopic characterization of protonated oxirane: a potential prebiotic species in Titan's atmosphere

International Nuclear Information System (INIS)

Giacomo Ciamician, Università di Bologna, Via Selmi 2, I-40126 Bologna (Italy))" data-affiliation=" (Dipartimento di Chimica Giacomo Ciamician, Università di Bologna, Via Selmi 2, I-40126 Bologna (Italy))" >Puzzarini, Cristina; Ali, Ashraf; Biczysko, Malgorzata; Barone, Vincenzo

2014-01-01

An accurate spectroscopic characterization of protonated oxirane has been carried out by means of state-of-the-art computational methods and approaches. The calculated spectroscopic parameters from our recent computational investigation of oxirane together with the corresponding experimental data available were used to assess the accuracy of our predicted rotational and IR spectra of protonated oxirane. We found an accuracy of about 10 cm –1 for vibrational transitions (fundamentals as well as overtones and combination bands) and, in relative terms, of 0.1% for rotational transitions. We are therefore confident that the spectroscopic data provided herein are a valuable support for the detection of protonated oxirane not only in Titan's atmosphere but also in the interstellar medium.

Accurate spectroscopic characterization of protonated oxirane: a potential prebiotic species in Titan's atmosphere

Energy Technology Data Exchange (ETDEWEB)

Puzzarini, Cristina [Dipartimento di Chimica " Giacomo Ciamician," Università di Bologna, Via Selmi 2, I-40126 Bologna (Italy); Ali, Ashraf [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Biczysko, Malgorzata; Barone, Vincenzo, E-mail: cristina.puzzarini@unibo.it [Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa (Italy)

2014-09-10

An accurate spectroscopic characterization of protonated oxirane has been carried out by means of state-of-the-art computational methods and approaches. The calculated spectroscopic parameters from our recent computational investigation of oxirane together with the corresponding experimental data available were used to assess the accuracy of our predicted rotational and IR spectra of protonated oxirane. We found an accuracy of about 10 cm{sup –1} for vibrational transitions (fundamentals as well as overtones and combination bands) and, in relative terms, of 0.1% for rotational transitions. We are therefore confident that the spectroscopic data provided herein are a valuable support for the detection of protonated oxirane not only in Titan's atmosphere but also in the interstellar medium.

Multiple spectroscopic studies of the structural conformational changes of human serum albumin—Essential oil based nanoemulsions conjugates

International Nuclear Information System (INIS)

Sekar, Gajalakshmi; Sugumar, Saranya; Mukherjee, Amitava; Chandrasekaran, Natarajan

2015-01-01

Nanoemulsions have numerous biomedical applications. For the first time, we have investigated the effects of orange and eucalyptus essential oil based nanoemulsions towards the structural aspect of human serum albumin (HSA). Quenching effect of nanoemulsion against the intrinsic fluorescence potential of tryptophan and tyrosine residues were evidenced from the fluorescence spectroscopic analysis. Static quenching mechanism was found to lead the binding of HSA–nanoemulsion systems. Synchronous and three dimensional spectroscopic studies have revealed the possible changes to the aromatic environment of HSA by the nanoemulsion. UV–Visible spectroscopic studies have confirmed the existence of the ground state complex formation between HSA and the surface of nanoemulsions by exhibiting the hyper-chromic effect in a concentration dependant manner. FTIR spectroscopy revealed the slight alteration in the Amide I, II and III bands of HSA after interaction. FT-Raman spectroscopy showed the decrease in the Raman intensity of the aromatic amino acid residues and shift in the amide bands of HSA upon binding with the nanoemulsion. Dichoric band obtained from the far UV-CD spectra at 208 and 222 nm of HSA showed the corresponding decrease in the alpha-helical contents upon interaction with nanoemulsions. Near UV-CD spectra also showed the prominent changes in the aromatic positions of the amino acid residues of HSA on binding with nanoemulsions. The above study has extrapolated the side effect analysis of the nanoemulsions in pharmaceutical applications in vitro in reference to their interaction with serum proteins. - Highlights: • Orange and eucalyptus oil based nanoemulsions were formulated and characterized. • UV–Visible spectroscopy confirmed the ground state complex formation. • Fluorescence spectroscopy confirmed the molecular conformational changes. • FTIR spectroscopy deep-rooted the alteration in the amide bands of HSA. • FT-Raman spectroscopy established

Multiple spectroscopic studies of the structural conformational changes of human serum albumin—Essential oil based nanoemulsions conjugates

Energy Technology Data Exchange (ETDEWEB)

Sekar, Gajalakshmi; Sugumar, Saranya; Mukherjee, Amitava; Chandrasekaran, Natarajan, E-mail: nchandra40@hotmail.com

2015-05-15

Nanoemulsions have numerous biomedical applications. For the first time, we have investigated the effects of orange and eucalyptus essential oil based nanoemulsions towards the structural aspect of human serum albumin (HSA). Quenching effect of nanoemulsion against the intrinsic fluorescence potential of tryptophan and tyrosine residues were evidenced from the fluorescence spectroscopic analysis. Static quenching mechanism was found to lead the binding of HSA–nanoemulsion systems. Synchronous and three dimensional spectroscopic studies have revealed the possible changes to the aromatic environment of HSA by the nanoemulsion. UV–Visible spectroscopic studies have confirmed the existence of the ground state complex formation between HSA and the surface of nanoemulsions by exhibiting the hyper-chromic effect in a concentration dependant manner. FTIR spectroscopy revealed the slight alteration in the Amide I, II and III bands of HSA after interaction. FT-Raman spectroscopy showed the decrease in the Raman intensity of the aromatic amino acid residues and shift in the amide bands of HSA upon binding with the nanoemulsion. Dichoric band obtained from the far UV-CD spectra at 208 and 222 nm of HSA showed the corresponding decrease in the alpha-helical contents upon interaction with nanoemulsions. Near UV-CD spectra also showed the prominent changes in the aromatic positions of the amino acid residues of HSA on binding with nanoemulsions. The above study has extrapolated the side effect analysis of the nanoemulsions in pharmaceutical applications in vitro in reference to their interaction with serum proteins. - Highlights: • Orange and eucalyptus oil based nanoemulsions were formulated and characterized. • UV–Visible spectroscopy confirmed the ground state complex formation. • Fluorescence spectroscopy confirmed the molecular conformational changes. • FTIR spectroscopy deep-rooted the alteration in the amide bands of HSA. • FT-Raman spectroscopy established

Infrared spectroscopic and voltammetric study of adsorbed CO on stepped surfaces of copper monocrystalline electrodes

International Nuclear Information System (INIS)

Koga, O.; Teruya, S.; Matsuda, K.; Minami, M.; Hoshi, N.; Hori, Y.

2005-01-01

Voltammetric and infrared (IR) spectroscopic measurements were carried out to study adsorbed CO on two series of copper single crystal electrodes n(111)-(111) and n(111)-(100) in 0.1M KH 2 PO 4 +0.1M K 2 HPO 4 at 0 o C. Reversible voltammetric waves were observed below -0.55V versus SHE for adsorption of CO which displaces preadsorbed phosphate anions. The electric charge of the redox waves is proportional to the step atom density for both single crystal series. This fact indicates that phosphate anions are specifically adsorbed on the step sites below -0.55V versus SHE. Voltammetric measurements indicated that (111) terrace of Cu is covered with adsorbed CO below -0.5V versus SHE. Nevertheless, no IR absorption band of adsorbed CO is detected from (111) terrace. Presence of adsorbed CO on (111) terrace is presumed which is not visible by the potential difference spectroscopy used in the present work. IR spectroscopic measurements showed that CO is reversibly adsorbed with an on-top manner on copper single crystal electrodes of n(111)-(111) and n(111)-(100) with approximately same wavenumber of C?O stretching vibration of 2070cm -1 . The IR band intensity is proportional to the step atom density. Thus CO is adsorbed on (111) or (100) steps on the single crystal surfaces. An analysis of the IR band intensity suggested that one CO molecule is adsorbed on every two or more Cu step atom of the monocrystalline surface. The spectroscopic data were compared with those reported for uhv system. The C-O stretching wavenumber of adsorbed CO in the electrode-electrolyte system is 30-40cm -1 lower than those in uhv system

Optimizing Spectroscopic and Photometric Galaxy Surveys: Same-Sky Benefits for Dark Energy and Modified Gravity

Energy Technology Data Exchange (ETDEWEB)

Kirk, Donnacha [University Coll. London; Lahav, Ofer [University Coll. London; Bridle, Sarah [Manchester U.; Jouvel, Stephanie [Barcelona, IEEC; Abdalla, Filipe B. [University Coll. London; Frieman, Joshua A. [Chicago U., KICP

2015-08-21

The combination of multiple cosmological probes can produce measurements of cosmological parameters much more stringent than those possible with any individual probe. We examine the combination of two highly correlated probes of late-time structure growth: (i) weak gravitational lensing from a survey with photometric redshifts and (ii) galaxy clustering and redshift space distortions from a survey with spectroscopic redshifts. We choose generic survey designs so that our results are applicable to a range of current and future photometric redshift (e.g. KiDS, DES, HSC, Euclid) and spectroscopic redshift (e.g. DESI, 4MOST, Sumire) surveys. Combining the surveys greatly improves their power to measure both dark energy and modified gravity. An independent, non-overlapping combination sees a dark energy figure of merit more than 4 times larger than that produced by either survey alone. The powerful synergies between the surveys are strongest for modified gravity, where their constraints are orthogonal, producing a non-overlapping joint figure of merit nearly 2 orders of magnitude larger than either alone. Our projected angular power spectrum formalism makes it easy to model the cross-correlation observable when the surveys overlap on the sky, producing a joint data vector and full covariance matrix. We calculate a same-sky improvement factor, from the inclusion of these cross-correlations, relative to non-overlapping surveys. We find nearly a factor of 4 for dark energy and more than a factor of 2 for modified gravity. The exact forecast figures of merit and same-sky benefits can be radically affected by a range of forecasts assumption, which we explore methodically in a sensitivity analysis. We show that that our fiducial assumptions produce robust results which give a good average picture of the science return from combining photometric and spectroscopic surveys.

Spectroscopic characterization of uranium in evaporation basin sediments

Science.gov (United States)

Duff, M. C.; Morris, D. E.; Hunter, D. B.; Bertsch, P. M.

2000-05-01

Evaporation ponds in the San Joaquin Valley (SJV), CA, used for the containment of irrigation drainage waters contain elevated levels of uranium (U) resulting from the extensive leaching by carbonate-rich irrigation waters of the local agricultural soils that contain low levels of naturally-occurring U. The SJV ponds are subjected to changes in redox chemistry with cycles of drying and flooding. Our past studies have shown that U in the SJV Pond 14 surface sediments is present as mostly the oxidized and soluble form, U(VI). However, we were uncertain whether the U in the soil was only present as a U oxide of mixed stoichiometry, such as U 3O 8(s) (pitchblende) or other species. Here we present characterization information, which includes wet chemical and in situ spectroscopic techniques (X-ray absorption near-edge structure (XANES) and low temperature time-resolved luminescence spectroscopies) for samples from two SJV Pond sediments. Surface sediments from SJV Pond 16 were characterized for average oxidation state of U with XANES spectroscopy. The fraction of U(VI) to U(IV) in the Pond 16 sediments decreased with depth with U(IV) being the dominant oxidation state in the 5 cm to 15 cm depth. Two luminescent U(VI) species were identified in the surface sediments from Pond 14; a U(VI)-tricarbonate phase and another phase likely comprised of U(VI)-hydroxide or hydroxycarbonate. The luminescent U(VI) population in the Pond 16 sediments is dominated by species with comparable spectral characteristics to the U(VI)-hydroxide or hydroxycarbonate species found in the Pond 14 sediments. The luminescence spectroscopic results were complemented by wet chemical U leaching methods, which involved the use of carbonate and sulfuric acid solutions and oxidizing solutions of peroxide, hypochlorite and Mn(IV). Leaching was shown to decrease the total U concentration in the sediments in all cases. However, results from luminescence studies of the residual fraction in the leached

Dielectric and impedance spectroscopic studies of neodymium gallate

Energy Technology Data Exchange (ETDEWEB)

Sakhya, Anup Pradhan, E-mail: npshakya31@gmail.com [Department of Physics, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009 (India); Dutta, Alo [Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata 700098 (India); Sinha, T.P. [Department of Physics, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009 (India)

2016-05-01

The AC electrical properties of a polycrystalline neodymium gallate, NdGaO{sub 3} (NGO), synthesized by the sol–gel method have been investigated by employing impedance spectroscopy in the frequency range from 42 Hz to 5 MHz and in the temperature range from 323 K to 593 K. The X-ray diffraction analysis shows that the compound crystallizes in the orthorhombic phase with Pbnm space group at room temperature. Two relaxation processes with different relaxation times are observed from the impedance as well as modulus spectroscopic measurements, which have been attributed to the grain and the grain boundary effects at different temperatures in NGO. The complex impedance data are analyzed by an electrical equivalent circuit consisting of a resistance and a constant phase element in parallel. It has been observed that the value of the capacitance and the resistance associated with the grain boundary is higher than those associated with the grain. The temperature dependent electrical conductivity shows the negative temperature coefficient of resistance. The frequency dependent conductivity spectra are found to follow the power law.

Spectroscopic enhancement in nanoparticles embedded glasses

Energy Technology Data Exchange (ETDEWEB)

Sahar, M. R., E-mail: mrahim057@gmail.com; Ghoshal, S. K., E-mail: mrahim057@gmail.com [Advanced Optical Material Research Group, Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310, Skudai, Johor Bahru, Johor (Malaysia)

2014-09-25

This presentation provides an overview of the recent progress in the enhancement of the spectroscopic characteristics of the glass embedded with nanoparticles (NPs). Some of our research activities with few significantly new results are highlighted and facilely analyzed. The science and technology dealing with the manipulation of the physical properties of rare earth doped inorganic glasses by embedding metallic NPs or nanoclusters produce the so-called 'nanoglass'. Meanwhile, the spectroscopic enhancement relates the intensity of the luminescence measured at certain transition. The enhancement which expectedly due to the 'plasmonics wave' (referring to the coherent coupling of photons to free electron oscillations called plasmon) occurs at the interface between a conductor and a dielectric. Plasmonics being an emerging concept in advanced optical material of nanophotonics has given this material the ability to exploit the optical response at nanoscale and opened up a new avenue in metal-based glass optics. There is a vast array of plasmonic NPs concepts yet to be explored, with applications spanning solar cells, (bio) sensing, communications, lasers, solid-state lighting, waveguides, imaging, optical data transfer, display and even bio-medicine. Localized surface plasmon resonance (LSPR) can enhance the optical response of nanoglass by orders of magnitude as observed. The luminescence enhancement and surface enhanced Raman scattering (SERS) are new paradigm of research. The enhancement of luminescence due to the influence of metallic NPs is the recurring theme of this paper.

Synthesis and spectroscopic properties of transfermium isotopes with Z = 105, 106 and 107

International Nuclear Information System (INIS)

Streicher, B.

2006-01-01

The quest for production of new elements has been on for several decades. On the way up the ladder of nuclear chart the systematic research of nuclear properties of elements in transfermium region has been severely overlooked. This drawback is being rectified in past few years by systematic synthesis of especially even-even and odd-A isotopes of these elements. This work proceeds forward also with major contribution of velocity filter SHIP, placed at GSI, Darmstadt. This experimental device represents a unique possibility due to high (up to 1 pμA) beam currents provided by UNILAC accelerator and advancing detection systems to study by means of decay spectroscopy the nuclear structure of isotopes for the elements, possibly up to proton number Z = 110. As the low lying single-particle levels are especially determined by the unpaired nucleon, the odd mass nuclei provide a valuable source of information about the nuclear structure. Such results can be directly compared with the predictions of the calculations based on macroscopic-microscopic model of nuclear matter, thus proving an unambiguous test of the correctness of present models and their power to predict nuclear properties towards yet unknown regions. This work concentrates on the spectroscopic analysis of few of such nuclei. Namely it deals with isotopes 261 Sg and 257 Rf with one unpaired neutron, as well as isotopes 257 Db and 253 Lr with one unpaired proton configuration. Moreover, the analysis of odd-odd nuclei of the the decay sequence 262 Bg → 258 Db → 254 Lr → produced in various experiments at SHIP is discussed in detail. Exhaustive spectroscopic analysis of these data is provided, revealing new information on α, β, EC and SF decay modes of these very heavy isotopes, and deepening the knowledge of the low lying single-particle level structure. Outcomes resulting from the comparison with the systematics of experimentally derived nuclear properties as well as with the predictions of the

GAS CHROMATOGRAPHIC AND SPECTROSCOPIC ANALYSIS OF ...

African Journals Online (AJOL)

Peroxyformic acid prepared in-situ was employed for epoxidation of canola oil in the presence of toluene. Gas chromatographic analysis of the product revealed the following species: C16:0; C18:0; C18:1; C18:2; C18:3; monoepoxy C18:0; monoepoxy C18:1; monoepoxy C18:2; diepoxy C18:0; diepoxy C18:1 and triepoxy ...

DIFFERENTIATION OF AURANTII FRUCTUS IMMATURUS AND FRUCTUS PONICIRI TRIFOLIATAE IMMATURUS BY FLOW-INJECTION WITH ULTRAVIOLET SPECTROSCOPIC DETECTION AND PROTON NUCLEAR MAGNETIC RESONANCE USING PARTIAL LEAST-SQUARES DISCRIMINANT ANALYSIS.

Science.gov (United States)

Zhang, Mengliang; Zhao, Yang; Harrington, Peter de B; Chen, Pei

2016-03-01

Two simple fingerprinting methods, flow-injection coupled to ultraviolet spectroscopy and proton nuclear magnetic resonance, were used for discriminating between Aurantii fructus immaturus and Fructus poniciri trifoliatae immaturus . Both methods were combined with partial least-squares discriminant analysis. In the flow-injection method, four data representations were evaluated: total ultraviolet absorbance chromatograms, averaged ultraviolet spectra, absorbance at 193, 205, 225, and 283 nm, and absorbance at 225 and 283 nm. Prediction rates of 100% were achieved for all data representations by partial least-squares discriminant analysis using leave-one-sample-out cross-validation. The prediction rate for the proton nuclear magnetic resonance data by partial least-squares discriminant analysis with leave-one-sample-out cross-validation was also 100%. A new validation set of data was collected by flow-injection with ultraviolet spectroscopic detection two weeks later and predicted by partial least-squares discriminant analysis models constructed by the initial data representations with no parameter changes. The classification rates were 95% with the total ultraviolet absorbance chromatograms datasets and 100% with the other three datasets. Flow-injection with ultraviolet detection and proton nuclear magnetic resonance are simple, high throughput, and low-cost methods for discrimination studies.

Ex-vivo holographic microscopy and spectroscopic analysis of head and neck cancer

Science.gov (United States)

Holler, Stephen; Wurtz, Robert; Auyeung, Kelsey; Auyeung, Kris; Paspaley-Grbavac, Milan; Mulroe, Brigid; Sobrero, Maximiliano; Miles, Brett

2015-03-01

Optical probes to identify tumor margins in vivo would greatly reduce the time, effort and complexity in the surgical removal of malignant tissue in head and neck cancers. Current approaches involve visual microscopy of stained tissue samples to determine cancer margins, which results in the excision of excess of tissue to assure complete removal of the cancer. Such surgical procedures and follow-on chemotherapy can adversely affect the patient's recovery and subsequent quality of life. In order to reduce the complexity of the process and minimize adverse effects on the patient, we investigate ex vivo tissue samples (stained and unstained) using digital holographic microscopy in conjunction with spectroscopic analyses (reflectance and transmission spectroscopy) in order to determine label-free, optically identifiable characteristic features that may ultimately be used for in vivo processing of cancerous tissues. The tissue samples studied were squamous cell carcinomas and associated controls from patients of varying age, gender and race. Holographic microscopic imaging scans across both cancerous and non-cancerous tissue samples yielded amplitude and phase reconstructions that were correlated with spectral signatures. Though the holographic reconstructions and measured spectra indicate variations even among the same class of tissue, preliminary results indicate the existence of some discriminating features. Further analyses are presently underway to further this work and extract additional information from the imaging and spectral data that may prove useful for in vivo surgical identification.

Vibrational spectroscopic study of fluticasone propionate

Science.gov (United States)

Ali, H. R. H.; Edwards, H. G. M.; Kendrick, J.; Scowen, I. J.

2009-03-01

Fluticasone propionate is a synthetic glucocorticoid with potent anti-inflammatory activity that has been used effectively in the treatment of chronic asthma. The present work reports a vibrational spectroscopic study of fluticasone propionate and gives proposed molecular assignments on the basis of ab initio calculations using BLYP density functional theory with a 6-31G* basis set and vibrational frequencies predicted within the quasi-harmonic approximation. Several spectral features and band intensities are explained. This study generated a library of information that can be employed to aid the process monitoring of fluticasone propionate.

Spectroscopic amplifier for pin diode; Amplificador espectroscopico para diodo Pin

Energy Technology Data Exchange (ETDEWEB)

Alonso M, M. S.; Hernandez D, V. M.; Vega C, H. R., E-mail: bebe.luna_s@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

2014-10-15

The photodiode remains the basic choice for the photo-detection and is widely used in optical communications, medical diagnostics and field of corpuscular radiation. In detecting radiation it has been used for monitoring radon and its progeny and inexpensive spectrometric systems. The development of a spectroscopic amplifier for Pin diode is presented which has the following characteristics: canceler Pole-Zero (P/Z) with a time constant of 8 μs; constant gain of 57, suitable for the acquisition system; 4th integrator Gaussian order to waveform change of exponential input to semi-Gaussian output and finally a stage of baseline restorer which prevents Dc signal contribution to the next stage. The operational amplifier used is the TLE2074 of BiFET technology of Texas Instruments with 10 MHz bandwidth, 25 V/μs of slew rate and a noise floor of 17 nv/(Hz)1/2. The integrated circuit has 4 operational amplifiers and in is contained the total of spectroscopic amplifier that is the goal of electronic design. The results show like the exponential input signal is converted to semi-Gaussian, modifying only the amplitude according to the specifications in the design. The total system is formed by the detector, which is the Pin diode, a sensitive preamplifier to the load, the spectroscopic amplifier that is what is presented and finally a pulse height analyzer (Mca) which is where the spectrum is shown. (Author)

Spectroscopic and electron-ion collision data for plasma impurities

International Nuclear Information System (INIS)

Faenov, A.; Marchand, R.; Tawara, H.; Vainshtein, L.; Wiese, W.

1992-01-01

This Working Group Report briefly reviews and summarizes the available spectroscopic and electron-ion collision data for plasma impurities. Included are lithium, neon, and argon, which, although they are not plasma impurities per se, are introduced into the plasma through the application of diagnostic techniques. 32 refs, 2 tabs

Combined spectroscopic imaging and chemometric approach for automatically partitioning tissue types in human prostate tissue biopsies

Science.gov (United States)

Haka, Abigail S.; Kidder, Linda H.; Lewis, E. Neil

2001-07-01

We have applied Fourier transform infrared (FTIR) spectroscopic imaging, coupling a mercury cadmium telluride (MCT) focal plane array detector (FPA) and a Michelson step scan interferometer, to the investigation of various states of malignant human prostate tissue. The MCT FPA used consists of 64x64 pixels, each 61 micrometers 2, and has a spectral range of 2-10.5 microns. Each imaging data set was collected at 16-1 resolution, resulting in 512 image planes and a total of 4096 interferograms. In this article we describe a method for separating different tissue types contained within FTIR spectroscopic imaging data sets of human prostate tissue biopsies. We present images, generated by the Fuzzy C-Means clustering algorithm, which demonstrate the successful partitioning of distinct tissue type domains. Additionally, analysis of differences in the centroid spectra corresponding to different tissue types provides an insight into their biochemical composition. Lastly, we demonstrate the ability to partition tissue type regions in a different data set using centroid spectra calculated from the original data set. This has implications for the use of the Fuzzy C-Means algorithm as an automated technique for the separation and examination of tissue domains in biopsy samples.

AKARI INFRARED CAMERA SURVEY OF THE LARGE MAGELLANIC CLOUD. II. THE NEAR-INFRARED SPECTROSCOPIC CATALOG

International Nuclear Information System (INIS)

Shimonishi, Takashi; Onaka, Takashi; Kato, Daisuke; Sakon, Itsuki; Ita, Yoshifusa; Kawamura, Akiko; Kaneda, Hidehiro

2013-01-01

We performed a near-infrared spectroscopic survey toward an area of ∼10 deg 2 of the Large Magellanic Cloud (LMC) with the infrared satellite AKARI. Observations were carried out as part of the AKARI Large-area Survey of the Large Magellanic Cloud (LSLMC). The slitless multi-object spectroscopic capability of the AKARI/IRC enabled us to obtain low-resolution (R ∼ 20) spectra in 2-5 μm for a large number of point sources in the LMC. As a result of the survey, we extracted about 2000 infrared spectra of point sources. The data are organized as a near-infrared spectroscopic catalog. The catalog includes various infrared objects such as young stellar objects (YSOs), asymptotic giant branch (AGB) stars, supergiants, and so on. It is shown that 97% of the catalog sources have corresponding photometric data in the wavelength range from 1.2 to 11 μm, and 67% of the sources also have photometric data up to 24 μm. The catalog allows us to investigate near-infrared spectral features of sources by comparison with their infrared spectral energy distributions. In addition, it is estimated that about 10% of the catalog sources are observed at more than two different epochs. This enables us to study a spectroscopic variability of sources by using the present catalog. Initial results of source classifications for the LSLMC samples are presented. We classified 659 LSLMC spectra based on their near-infrared spectral features by visual inspection. As a result, it is shown that the present catalog includes 7 YSOs, 160 C-rich AGBs, 8 C-rich AGB candidates, 85 O-rich AGBs, 122 blue and yellow supergiants, 150 red super giants, and 128 unclassified sources. Distributions of the classified sources on the color-color and color-magnitude diagrams are discussed in the text. Continuous wavelength coverage and high spectroscopic sensitivity in 2-5 μm can only be achieved by space observations. This is an unprecedented large-scale spectroscopic survey toward the LMC in the near

Electrochemical and spectroscopic studies of tungstencarbonyl complexes containing nitrogen and phosphorous ligands

Directory of Open Access Journals (Sweden)

Haddad Paula S.

2000-01-01

Full Text Available The present work deals with the synthesis, spectroscopic investigation and electrochemical behaviour of the compounds [W(CO4(bipy] (1, [W(CO3(bipy(dppm] (2 and [W(CO3(bipy(dppf] (3, bipy = 2,2'-bipyridine; dppm = bis(diphenylphosphinomethane; dppf = 1,1'-bis(diphenylphosphinoferrocene. The IR and 31P{¹H} NMR spectroscopic data have shown an octahedral coordination geometry for the tungsten atom with the diphosphines acting as monodentate ligands. The electrochemical behaviour of the complexes was investigated by cyclic voltammetry and controlled potential coulometry. Cyclic voltammograms have indicated that the compounds containing diphosphines ligands are more stable towards oxidation than compound (1.

Optimizing hydroxyl airglow retrievals from long-slit astronomical spectroscopic observations

Directory of Open Access Journals (Sweden)

C. Franzen

2017-08-01

Full Text Available Astronomical spectroscopic observations from ground-based telescopes contain background emission lines from the terrestrial atmosphere's airglow. In the near infrared, this background is composed mainly of emission from Meinel bands of hydroxyl (OH, which is produced in highly excited vibrational states by reduction of ozone near 90 km. This emission contains a wealth of information on the chemical and dynamical state of the Earth's atmosphere. However, observation strategies and data reduction processes are usually optimized to minimize the influence of these features on the astronomical spectrum. Here we discuss a measurement technique to optimize the extraction of the OH airglow signal itself from routine J-, H-, and K-band long-slit astronomical spectroscopic observations. As an example, we use data recorded from a point-source observation by the Nordic Optical Telescope's intermediate-resolution spectrograph, which has a spatial resolution of approximately 100 m at the airglow layer. Emission spectra from the OH vibrational manifold from v′  =  9 down to v′  =  3, with signal-to-noise ratios up to 280, have been extracted from 10.8 s integrations. Rotational temperatures representative of the background atmospheric temperature near 90 km, the mesosphere and lower thermosphere region, can be fitted to the OH rotational lines with an accuracy of around 0.7 K. Using this measurement and analysis technique, we derive a rotational temperature distribution with v′ that agrees with atmospheric model conditions and the preponderance of previous work. We discuss the derived rotational temperatures from the different vibrational bands and highlight the potential for both the archived and future observations, which are at unprecedented spatial and temporal resolutions, to contribute toward the resolution of long-standing problems in atmospheric physics.

Dealing with inaccuracies in the analysis on solvent-induced swelling of transparent thin films using in situ spectroscopic ellipsometry in the visible wavelength range

NARCIS (Netherlands)

Tempelman, Kristianne; Kappert, Emiel; Raaijmaker, Michiel J.T.; Wormeester, Herbert; Benes, Nieck Edwin

2016-01-01

The accuracy of spectroscopic ellipsometry studies of transparent polymer films in the visible wavelength range is greatly reduced in the presence of a liquid ambient. The relatively high refractive index of a liquid ambient strongly amplifies the effects of experimental non-idealities, such as

Identification and Spectroscopic Characterization of Nonheme Iron(III) Hypochlorite Intermediates

NARCIS (Netherlands)

Draksharapu, Apparao; Angelone, Davide; Quesne, Matthew G.; Padamati, Sandeep K.; Gomez, Laura; Hage, Ronald; Costas, Miquel; Browne, Wesley R.; de Visser, Sam P.

2015-01-01

Fe-III-hypohalite complexes have been implicated in a wide range of important enzyme-catalyzed halogenation reactions including the biosynthesis of natural products and antibiotics and post-translational modification of proteins. The absence of spectroscopic data on such species precludes their

Vibrational Spectroscopic Studies of Tenofovir Using Density Functional Theory Method

Directory of Open Access Journals (Sweden)

G. R. Ramkumaar

2013-01-01

Full Text Available A systematic vibrational spectroscopic assignment and analysis of tenofovir has been carried out by using FTIR and FT-Raman spectral data. The vibrational analysis was aided by electronic structure calculations—hybrid density functional methods (B3LYP/6-311++G(d,p, B3LYP/6-31G(d,p, and B3PW91/6-31G(d,p. Molecular equilibrium geometries, electronic energies, IR intensities, and harmonic vibrational frequencies have been computed. The assignments proposed based on the experimental IR and Raman spectra have been reviewed and complete assignment of the observed spectra have been proposed. UV-visible spectrum of the compound was also recorded and the electronic properties such as HOMO and LUMO energies and were determined by time-dependent DFT (TD-DFT method. The geometrical, thermodynamical parameters, and absorption wavelengths were compared with the experimental data. The B3LYP/6-311++G(d,p-, B3LYP/6-31G(d,p-, and B3PW91/6-31G(d,p-based NMR calculation procedure was also done. It was used to assign the 13C and 1H NMR chemical shift of tenofovir.

The optical characterization of organometallic complex thin films by spectroscopic ellipsometry and photovoltaic diode application

International Nuclear Information System (INIS)

Özaydın, C.; Güllü, Ö.; Pakma, O.; Ilhan, S.; Akkılıç, K.

2016-01-01

Highlights: • Optical properties and thickness of the A novel organometallic complex (OMC) film were investigated by spectroscopic ellipsometry (SE). • Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated • This paper presents the I–V analysis of Au/OMC/n-Si MIS diode. • Current–voltage and photovoltaic properties of the diode were investigated. - Abstract: In this work, organometallic complex (OMC) films have been deposited onto glass or silicon substrates by spin coating technique and their photovoltaic application potential has been investigated. Optical properties and thickness of the film have been investigated by spectroscopic ellipsometry (SE). Also, transmittance spectrum has been taken by UV/vis spectrophotometer. The optical method has been used to determine the band gap value of the films. Also, Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated. Current–voltage and photovoltaic properties of the structure were investigated. The ideality factor (n) and barrier height (Φ_b) values of the diode were found to be 2.89 and 0.79 eV, respectively. The device shows photovoltaic behavior with a maximum open-circuit voltage of 396 mV and a short circuit current of 33.8 μA under 300 W light.

Updating a synchronous fluorescence spectroscopic virgin olive oil adulteration calibration to a new geographical region.

Science.gov (United States)

Kunz, Matthew Ross; Ottaway, Joshua; Kalivas, John H; Georgiou, Constantinos A; Mousdis, George A

2011-02-23

Detecting and quantifying extra virgin olive adulteration is of great importance to the olive oil industry. Many spectroscopic methods in conjunction with multivariate analysis have been used to solve these issues. However, successes to date are limited as calibration models are built to a specific set of geographical regions, growing seasons, cultivars, and oil extraction methods (the composite primary condition). Samples from new geographical regions, growing seasons, etc. (secondary conditions) are not always correctly predicted by the primary model due to different olive oil and/or adulterant compositions stemming from secondary conditions not matching the primary conditions. Three Tikhonov regularization (TR) variants are used in this paper to allow adulterant (sunflower oil) concentration predictions in samples from geographical regions not part of the original primary calibration domain. Of the three TR variants, ridge regression with an additional 2-norm penalty provides the smallest validation sample prediction errors. Although the paper reports on using TR for model updating to predict adulterant oil concentration, the methods should also be applicable to updating models distinguishing adulterated samples from pure extra virgin olive oil. Additionally, the approaches are general and can be used with other spectroscopic methods and adulterants as well as with other agriculture products.

The central star candidate of the planetary nebula Sh2-71: photometric and spectroscopic variability

Science.gov (United States)

Močnik, T.; Lloyd, M.; Pollacco, D.; Street, R. A.

2015-07-01

We present the analysis of several newly obtained and archived photometric and spectroscopic data sets of the intriguing and yet poorly understood 13.5 mag central star candidate of the bipolar planetary nebula Sh2-71. Photometric observations confirmed the previously determined quasi-sinusoidal light curve with a period of 68 d and also indicated periodic sharp brightness dips, possibly eclipses, with a period of 17.2 d. In addition, the comparison between U and V light curves revealed that the 68 d brightness variations are accompanied by a variable reddening effect of ΔE(U - V) = 0.38. Spectroscopic data sets demonstrated pronounced variations in spectral profiles of Balmer, helium and singly ionized metal lines and indicated that these variations occur on a time-scale of a few days. The most accurate verification to date revealed that spectral variability is not correlated with the 68 d brightness variations. The mean radial velocity of the observed star was measured to be ˜26 km s-1 with an amplitude of ±40 km s-1. The spectral type was determined to be B8V through spectral comparison with synthetic and standard spectra. The newly proposed model for the central star candidate is a Be binary with a misaligned precessing disc.

The optical characterization of organometallic complex thin films by spectroscopic ellipsometry and photovoltaic diode application

Energy Technology Data Exchange (ETDEWEB)

Özaydın, C. [Batman University, Engineering Faculty, Department of Computer Eng., Batman (Turkey); Güllü, Ö., E-mail: omergullu@gmail.com [Batman University, Science and Art Faculty, Department of Physics, Batman (Turkey); Pakma, O. [Batman University, Science and Art Faculty, Department of Physics, Batman (Turkey); Ilhan, S. [Siirt University, Science and Art Faculty, Department of Chemistry, Siirt (Turkey); Akkılıç, K. [Dicle University, Education Faculty, Department of Physics Education, Diyarbakır (Turkey)

2016-05-15

Highlights: • Optical properties and thickness of the A novel organometallic complex (OMC) film were investigated by spectroscopic ellipsometry (SE). • Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated • This paper presents the I–V analysis of Au/OMC/n-Si MIS diode. • Current–voltage and photovoltaic properties of the diode were investigated. - Abstract: In this work, organometallic complex (OMC) films have been deposited onto glass or silicon substrates by spin coating technique and their photovoltaic application potential has been investigated. Optical properties and thickness of the film have been investigated by spectroscopic ellipsometry (SE). Also, transmittance spectrum has been taken by UV/vis spectrophotometer. The optical method has been used to determine the band gap value of the films. Also, Au/OMC/n-Si metal/interlayer/semiconductor (MIS) diode has been fabricated. Current–voltage and photovoltaic properties of the structure were investigated. The ideality factor (n) and barrier height (Φ{sub b}) values of the diode were found to be 2.89 and 0.79 eV, respectively. The device shows photovoltaic behavior with a maximum open-circuit voltage of 396 mV and a short circuit current of 33.8 μA under 300 W light.

Spectroscopic profiling and computational study of the binding of tschimgine: A natural monoterpene derivative, with calf thymus DNA

Science.gov (United States)

Khajeh, Masoumeh Ashrafi; Dehghan, Gholamreza; Dastmalchi, Siavoush; Shaghaghi, Masoomeh; Iranshahi, Mehrdad

2018-03-01

DNA is a major target for a number of anticancer substances. Interaction studies between small molecules and DNA are essential for rational drug designing to influence main biological processes and also introducing new probes for the assay of DNA. Tschimgine (TMG) is a monoterpene derivative with anticancer properties. In the present study we tried to elucidate the interaction of TMG with calf thymus DNA (CT-DNA) using different spectroscopic methods. UV-visible absorption spectrophotometry, fluorescence and circular dichroism (CD) spectroscopies as well as molecular docking study revealed formation of complex between TMG and CT-DNA. Binding constant (Kb) between TMG and DNA was 2.27 × 104 M- 1, that is comparable to groove binding agents. The fluorescence spectroscopic data revealed that the quenching mechanism of fluorescence of TMG by CT-DNA is static quenching. Thermodynamic parameters (ΔH TMG with CT-DNA. Competitive binding assay with methylene blue (MB) and Hoechst 33258 using fluorescence spectroscopy displayed that TMG possibly binds to the minor groove of CT-DNA. These observations were further confirmed by CD spectral analysis, viscosity measurements and molecular docking.

Quality of sour cherry juice of different clones and cultivars (Prunus cerasus L.) determined by a combined sensory and NMR spectroscopic approach

DEFF Research Database (Denmark)

Clausen, Morten Rahr; Pedersen, Bjarne Hjelmsted; Bertram, Hanne Christine S.

2011-01-01

Juice was manufactured from seven different sour cherry clones/cultivars and evaluated by quantitative descriptive sensory analysis and 1H NMR spectroscopy. The sensory evaluation showed a large variation in several sensory attributes between the sour cherry clones/cultivars, which could be divided...... into two groups on the basis of both the sensory data and the NMR spectroscopic data. These groups were closely related to the genetic background of the clones. Kelleris clones were distinctly different from Stevnsberry and Fanal clones. Hence, 1H NMR spectroscopic data seem to correlate with sensory...... quality of different sour cherry clones. In addition, malic acid was the most important metabolite for modeling the two highly correlated sensory attributes sweetness and sourness, whereas the glucose content had a slight effect and the fructose content had no impact on sweetness/sourness. Other...

Optical spectroscopic elucidation of beta-turns in disulfide bridged cyclic tetrapeptides.

Science.gov (United States)

Borics, Attila; Murphy, Richard F; Lovas, Sándor

2007-01-01

Vibrational circular dichroism (VCD) spectroscopic features of type II beta-turns were characterized previously, but, criteria for differentiation between beta-turn types had not been established yet. Model tetrapeptides, cyclized through a disulfide bridge, were designed on the basis of previous experimental results and the observed incidence of amino acid residues in the i + 1 and i + 2 positions in beta-turns, to determine the features of VCD spectra of type I and II beta-turns. The results were correlated with electronic circular dichroism (ECD) spectra and VCD spectra calculated from conformational data obtained by molecular dynamics (MD) simulations. All cyclic tetrapeptides yielded VCD signals with a higher frequency negative and a lower frequency positive couplet with negative lobes overlapping. MD simulations confirmed the conformational homogeneity of these peptides in solution. Comparison with ECD spectroscopy, MD, and quantum chemical calculation results suggested that the low frequency component of VCD spectra originating from the tertiary amide vibrations could be used to distinguish between types of beta-turn structures. On the basis of this observation, VCD spectroscopic features of type II and VIII beta-turns and ECD spectroscopic properties of a type VIII beta-turn were suggested. The need for independent experimental as well as theoretical investigations to obtain decisive conformational information was recognized. Copyright 2006 Wiley Periodicals, Inc.

PHOTOMETRIC AND SPECTROSCOPIC PROPERTIES OF NOVAE IN THE LARGE MAGELLANIC CLOUD

International Nuclear Information System (INIS)

Shafter, A. W.

2013-01-01

The photometric and spectroscopic properties of the 43 known LMC nova candidates are summarized and reviewed. Of these, photometric data sufficient to establish decline rates are available for 29 novae, while spectroscopic data sufficient to establish the spectroscopic classes are available for 18 systems. Half of the 18 novae belong to the Fe II class, with the remaining nine belonging to either the He/N or the Fe IIb classes. As seen in previous nova studies of M31 and M33, the He/N and Fe IIb novae have on average faster photometric developments than do their Fe II counterparts. Overall, the available photometry confirms earlier studies, and shows conclusively that LMC novae have faster rates of decline than do novae in the Galaxy and M31. It appears that the increased fraction of faster, He/N and Fe IIb novae observed in the LMC compared with M31 is almost certainly the result of differences in the underlying stellar population between the two galaxies. We propose that the younger population seen in the LMC compared with M31's bulge (where most of the novae are found), produces progenitor binaries with higher average white dwarf masses. The higher mean white dwarf mass not only produces a larger fraction of fast, He/N novae compared with M31, but also results in a relatively large recurrent nova population.

THE APOKASC CATALOG: AN ASTEROSEISMIC AND SPECTROSCOPIC JOINT SURVEY OF TARGETS IN THE KEPLER FIELDS

Energy Technology Data Exchange (ETDEWEB)

Pinsonneault, Marc H.; Epstein, Courtney; Johnson, Jennifer A. [Department of Astronomy, The Ohio State University, Columbus, OH 43210 (United States); Elsworth, Yvonne; Chaplin, William J. [University of Birmingham, School of Physics and Astronomy, Edgbaston, Birmingham B15 2TT (United Kingdom); Hekker, Saskia; Silva Aguirre, Victor; Stello, Dennis [Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Mészáros, Sz. [Astronomy Department, Indiana University, Bloomington, IN 47405 (United States); García, Rafael A.; Beck, Paul [Laboratoire AIM, CEA/DSM-CNRS—Université Denis Diderot-IRFU/SAp, F-91191 Gif-sur-Yvette Cedex (France); Holtzman, Jon [Department of Astronomy, MSC 4500, New Mexico State University, P.O. Box 30001, Las Cruces, NM 88003 (United States); Mathur, Savita [Space Science Institute, 4750 Walnut street, Suite 205, Boulder, CO 80301 (United States); García Pérez, Ana [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States); Girardi, Léo [Osservatorio Astronomico di Padova—INAF, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Basu, Sarbani [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Shetrone, Matthew [University of Texas at Austin, McDonald Observatory, 32 Fowlkes Road, TX 79734-3005 (United States); Allende Prieto, Carlos [Instituto de Astrofsica de Canarias (IAC), C/Va Lactea, s/n, E-38200 La Laguna, Tenerife (Spain); An, Deokkeun [Department of Science Education, Ewha Womans University, Seoul (Korea, Republic of); Beers, Timothy C., E-mail: pinsonneault.1@osu.edu [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN 46656 (United States); and others

2015-01-01

We present the first APOKASC catalog of spectroscopic and asteroseismic properties of 1916 red giants observed in the Kepler fields. The spectroscopic parameters provided from the Apache Point Observatory Galactic Evolution Experiment project are complemented with asteroseismic surface gravities, masses, radii, and mean densities determined by members of the Kepler Asteroseismology Science Consortium. We assess both random and systematic sources of error and include a discussion of sample selection for giants in the Kepler fields. Total uncertainties in the main catalog properties are of the order of 80 K in T {sub eff}, 0.06 dex in [M/H], 0.014 dex in log g, and 12% and 5% in mass and radius, respectively; these reflect a combination of systematic and random errors. Asteroseismic surface gravities are substantially more precise and accurate than spectroscopic ones, and we find good agreement between their mean values and the calibrated spectroscopic surface gravities. There are, however, systematic underlying trends with T {sub eff} and log g. Our effective temperature scale is between 0 and 200 K cooler than that expected from the infrared flux method, depending on the adopted extinction map, which provides evidence for a lower value on average than that inferred for the Kepler Input Catalog (KIC). We find a reasonable correspondence between the photometric KIC and spectroscopic APOKASC metallicity scales, with increased dispersion in KIC metallicities as the absolute metal abundance decreases, and offsets in T {sub eff} and log g consistent with those derived in the literature. We present mean fitting relations between APOKASC and KIC observables and discuss future prospects, strengths, and limitations of the catalog data.

The 2003 edition of geisa: a spectroscopic database system for the second generation vertical sounders radiance simulation

Science.gov (United States)

Jacquinet-Husson, N.; Lmd Team

The GEISA (Gestion et Etude des Informations Spectroscopiques Atmosphériques: Management and Study of Atmospheric Spectroscopic Information) computer accessible database system, in its former 1997 and 2001 versions, has been updated in 2003 (GEISA-03). It is developed by the ARA (Atmospheric Radiation Analysis) group at LMD (Laboratoire de Météorologie Dynamique, France) since 1974. This early effort implemented the so-called `` line-by-line and layer-by-layer '' approach for forward radiative transfer modelling action. The GEISA 2003 system comprises three databases with their associated management softwares: a database of spectroscopic parameters required to describe adequately the individual spectral lines belonging to 42 molecules (96 isotopic species) and located in a spectral range from the microwave to the limit of the visible. The featured molecules are of interest in studies of the terrestrial as well as the other planetary atmospheres, especially those of the Giant Planets. a database of absorption cross-sections of molecules such as chlorofluorocarbons which exhibit unresolvable spectra. a database of refractive indices of basic atmospheric aerosol components. Illustrations will be given of GEISA-03, data archiving method, contents, management softwares and Web access facilities at: http://ara.lmd.polytechnique.fr The performance of instruments like AIRS (Atmospheric Infrared Sounder; http://www-airs.jpl.nasa.gov) in the USA, and IASI (Infrared Atmospheric Sounding Interferometer; http://smsc.cnes.fr/IASI/index.htm) in Europe, which have a better vertical resolution and accuracy, compared to the presently existing satellite infrared vertical sounders, is directly related to the quality of the spectroscopic parameters of the optically active gases, since these are essential input in the forward models used to simulate recorded radiance spectra. For these upcoming atmospheric sounders, the so-called GEISA/IASI sub-database system has been elaborated

In situ spectroscopic ellipsometry as a surface sensitive tool to probe thin film growth

International Nuclear Information System (INIS)

Liu, C.

1999-01-01

Sputtered thin film and multilayer x-ray mirrors are made routinely at the Advanced Photon Source (APS) for the APS users. Precise film growth control and characterization are very critical in fabricating high-quality x-ray mirrors. Film thickness calibrations are carried out using in situ and ex situ spectroscopic ellipsometry, interferometry, and x-ray scattering. To better understand the growth and optical properties of different thin film systems, we have carried out a systematic study of sputtered thin films of Au, Rh, Pg Pd, Cu, and Cr, using in situ ellipsometry. Multiple data sets were obtained in situ for each film material with incremental thicknesses and were analyzed with their correlation in mind. We found that in situ spectroscopic ellipsometry as a surface-sensitive tool can also be used to probe the growth and morphology of the thin film system. This application of in situ spectroscopic ellipsometry for metal thin film systems will be discussed

NARROW-LINE X-RAY-SELECTED GALAXIES IN THE CHANDRA -COSMOS FIELD. I. OPTICAL SPECTROSCOPIC CATALOG

Energy Technology Data Exchange (ETDEWEB)

Pons, E.; Watson, M. G. [University of Leicester, Leicester (United Kingdom); Elvis, M.; Civano, F. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)

2016-04-20

The COSMOS survey is a large and deep survey with multiwavelength observations of sources from X-rays to the UV, allowing an extensive study of their properties. The central 0.9 deg{sup 2} of the COSMOS field have been observed by Chandra with a sensitivity up to 1.9 × 10{sup −16} erg cm{sup −2} s{sup −1} in the full (0.5–10 keV) band. Photometric and spectroscopic identification of the Chandra -COSMOS (C-COSMOS) sources is available from several catalogs and campaigns. Despite the fact that the C-COSMOS galaxies have a reliable spectroscopic redshift in addition to a spectroscopic classification, the emission-line properties of this sample have not yet been measured. We present here the creation of an emission-line catalog of 453 narrow-line sources from the C-COSMOS spectroscopic sample. We have performed spectral fitting for the more common lines in galaxies ([O ii] λ 3727, [Ne iii] λ 3869, H β , [O iii] λλ 4959, 5007, H α , and [N ii] λλ 6548, 6584). These data provide an optical classification for 151 (i.e., 33%) of the C-COSMOS narrow-line galaxies based on emission-line diagnostic diagrams.

Proposal of AAA-battery-size one-shot ATR Fourier spectroscopic imager for on-site analysis: Simultaneous measurement of multi-components with high accuracy

Science.gov (United States)

Hosono, Satsuki; Qi, Wei; Sato, Shun; Suzuki, Yo; Fujiwara, Masaru; Hiramatsu, Hiroyuki; Suzuki, Satoru; Abeygunawardhana, P. K. W.; Wada, Kenji; Nishiyama, Akira; Ishimaru, Ichiro

2015-03-01

For simultaneous measurement of multi-components on-site like factories, the ultra-compact (diameter: 9[mm], length: 45[mm], weight: 200[g]) one-shot ATR (Attenuated Total Reflection) Fourier spectroscopic imager was proposed. Because the proposed one-shot Fourier spectroscopic imaging is based on spatial-phase-shift interferometer, interferograms could be obtained with simple optical configurations. We introduced the transmission-type relativeinclined phase-shifter, that was constructed with a cuboid prism and a wedge prism, onto the optical Fourier transform plane of infinity corrected optical systems. And also, small light-sources and cameras in the mid-infrared light region, whose size are several millimeter on a side, are essential components for the ultra-compact spectroscopic configuration. We selected the Graphite light source (light source area: 1.7×1.7[mm], maker: Hawkeye technologies) whose radiation factor was high. Fortunately, in these days we could apply the cost-effective 2-dimensional light receiving device for smartphone (e.g. product name: LEPTON, maker: FLIR, price: around 400USD). In the case of alcoholic drinks factory, conventionally workers measure glucose and ethanol concentrations by bringing liquid solution back to laboratories every day. The high portable spectroscopy will make it possible to measure multi-components simultaneously on manufacturing scene. But we found experimentally that absorption spectrum of glucose and water and ethanol were overlapped each other in near infrared light region. But for mid-infrared light region, we could distinguish specific absorption peaks of glucose (@10.5[μm]) and ethanol (@11.5[μm]) independently from water absorption. We obtained standard curve between absorption (@9.6[μm]) and ethanol concentration with high correlation coefficient 0.98 successfully by ATR imaging-type 2-dimensional Fourier spectroscopy (wavelength resolution: 0.057[μm]) with the graphite light source (maker: Hawkeye

Spectroscopic investigations (FT-IR & FT-Raman) and molecular docking analysis of 6-[1-methyl-4-nitro-1H-imidazol-5-yl) sulfonyl]-7H-purine

Science.gov (United States)

Prasath, M.; Govindammal, M.; Sathya, B.

2017-10-01

The Azathioprine is used as anticancer agent. Azathioprine is chemically called 6-[1-methyl-4-nitro-1H-imidazol-5-yl) sulfonyl]-7H-purine (6M4N5P). The vibrational analysis of the 6M4N5P compound was carried out by using FT-IR and FT-Raman spectroscopic techniques and compared with aspects. The optimized geometry, frequency and intensity of the vibrational bands of 6M4N5P were obtained from the HF and DFT methods with 6-31G (d,p) basis set. The harmonic vibrational frequencies were calculated and the scaled values have been compared with experimental FT-IR and FT-Raman spectra. The calculated Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) energies show that charge transfer occur within the molecule. MEP (Molecular Electrostatic Potential) is very useful in the investigation of the charge distributions and molecular structure. The molecule orbital contributions were determined by using the total density of states (TDOS). A molecular docking analysis has been carried out to understand the conformational change and electrostatic properties of 6M4N5P in the active site of Rac1-Receptor.

FTIR and Raman spectroscopic studies of selenium nanoparticles synthesised by the bacterium Azospirillum thiophilum

Science.gov (United States)

Tugarova, Anna V.; Mamchenkova, Polina V.; Dyatlova, Yulia A.; Kamnev, Alexander A.

2018-03-01

Vibrational (Fourier transform infrared (FTIR) and Raman) spectroscopic techniques can provide unique molecular-level information on the structural and compositional characteristics of complicated biological objects. Thus, their applications in microbiology and related fields are steadily increasing. In this communication, biogenic selenium nanoparticles (Se NPs) were obtained via selenite (SeO32-) reduction by the bacterium Azospirillum thiophilum (strain VKM B-2513) for the first time, using an original methodology for obtaining extracellular NPs. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) showed the Se NPs to have average diameters within 160-250 nm; their zeta potential was measured to be minus 18.5 mV. Transmission FTIR spectra of the Se NPs separated from bacterial cells showed typical proteinacious, polysaccharide and lipid-related bands, in line with TEM data showing a thin layer covering the Se NPs surface. Raman spectra of dried Se NPs layer in the low-frequency region (under 500 cm-1 down to 150 cm-1) showed a single very strong band with a maximum at 250 cm-1 which, in line with its increased width (ca. 30 cm-1 at half intensity), can be attributed to amorphous elementary Se. Thus, a combination of FTIR and Raman spectroscopic approaches is highly informative in non-destructive analysis of structural and compositional properties of biogenic Se NPs.

Influence of Gd2O3 on thermal and spectroscopic properties of aluminosilicate glasses

Science.gov (United States)

Kasprzyk, Marta; Środa, Marcin

2018-06-01

A series of aluminosilicate glasses 25SiO2·(20-x)Al2O3·40Na2O·15BaO-xGd2O3 with 0 ≤ x ≤ 10 were prepared in order to analyze the influence of gadolinium on thermal and spectroscopic properties of these materials. Increasing of thermal parameters (Tg, Tx, Δcp, ΔT) values with higher Gd2O3 content was determined using DSC method. Crystalline phases, formed during heat treatment, were identified with XRD - NaAlSiO4 and BaSiO3 in glass with 0% mol. Gd2O3 and Gd9.33(SiO4)6O2, NaAlSiO4 and BaAl2Si2O6 in glass with 10% mol. Gd2O3. Spectroscopic analysis - FTIR and Raman - revealed Gd2O3 influence on glass structure in the same way like Al2O3, but some differences appear due to the differ bond strength and ionic radius between Gd and Al. Raman spectra confirmed higher network polymerization (enriched with Q2 units). Optical band gap energy (Eopt) and Urbach energy (ΔE) were calculated from the Tauc plot. Mechanical tests demonstrated lower microhardness with increasing content of Gd2O3 content, as a result of higher concentration of atoms with larger radius.

SSGSS: THE SPITZER–SDSS–GALEX SPECTROSCOPIC SURVEY

International Nuclear Information System (INIS)

O'Dowd, Matthew J.; Schiminovich, David; Johnson, Benjamin D.; Treyer, Marie A.; Martin, Christopher D.; Wyder, Ted K.; Charlot, Stéphane; Heckman, Timothy M.; Martins, Lucimara P.; Seibert, Mark; Van der Hulst, J. M.

2011-01-01

The Spitzer-SDSS-GALEX Spectroscopic Survey (SSGSS) provides a new sample of 101 star-forming galaxies at z < 0.2 with unprecedented multi-wavelength coverage. New mid- to far-infrared spectroscopy from the Spitzer Space Telescope is added to a rich suite of previous imaging and spectroscopy, including ROSAT, Galaxy Evolution Explorer, Sloan Digital Sky Survey, Two Micron All Sky Survey, and Spitzer/SWIRE. Sample selection ensures an even coverage of the full range of normal galaxy properties, spanning two orders of magnitude in stellar mass, color, and dust attenuation. In this paper we present the SSGSS data set, describe the science drivers, and detail the sample selection, observations, data reduction, and quality assessment. Also in this paper, we compare the shape of the thermal continuum and the degree of silicate absorption of these typical, star-forming galaxies to those of starburst galaxies. We investigate the link between star formation rate, infrared luminosity, and total polycyclic aromatic hydrocarbon luminosity, with a view to calibrating the latter for spectral energy distribution models in photometric samples and at high redshift. Last, we take advantage of the 5-40 μm spectroscopic and far-infrared photometric coverage of this sample to perform detailed fitting of the Draine et al. dust models, and investigate the link between dust mass and star formation history and active galactic nucleus properties.

EPSILON AURIGAE: AN IMPROVED SPECTROSCOPIC ORBITAL SOLUTION

International Nuclear Information System (INIS)

Stefanik, Robert P.; Torres, Guillermo; Lovegrove, Justin; Latham, David W.; Zajac, Joseph; Pera, Vivian E.; Mazeh, Tsevi

2010-01-01

A rare eclipse of the mysterious object ε Aurigae will occur in 2009-2011. We report an updated single-lined spectroscopic solution for the orbit of the primary star based on 20 years of monitoring at the CfA, combined with historical velocity observations dating back to 1897. There are 518 new CfA observations obtained between 1989 and 2009. Two solutions are presented. One uses the velocities outside the eclipse phases together with mid-times of previous eclipses, from photometry dating back to 1842, which provide the strongest constraint on the ephemeris. This yields a period of 9896.0 ± 1.6 days (27.0938 ± 0.0044 years) with a velocity semi-amplitude of 13.84 ± 0.23 km s -1 and an eccentricity of 0.227 ± 0.011. The middle of the current ongoing eclipse predicted by this combined fit is JD 2,455,413.8 ± 4.8, corresponding to 2010 August 5. If we use only the radial velocities, we find that the predicted middle of the current eclipse is nine months earlier. This would imply that the gravitating companion is not the same as the eclipsing object. Alternatively, the purely spectroscopic solution may be biased by perturbations in the velocities due to the short-period oscillations of the supergiant.

Spectroscopic detection, characterization and dynamics of free radicals relevant to combustion processes

Energy Technology Data Exchange (ETDEWEB)

Miller, Terry [The Ohio State Univ., Columbus, OH (United States)

2015-06-04

Combustion chemistry is enormously complex. The chemical mechanisms involve a multitude of elementary reaction steps and a comparable number of reactive intermediates, many of which are free radicals. Computer simulations based upon these mechanisms are limited by the validity of the mechanisms and the parameters characterizing the properties of the intermediates and their reactivity. Spectroscopy can provide data for sensitive and selective diagnostics to follow their reactions. Spectroscopic analysis also provides detailed parameters characterizing the properties of these intermediates. These parameters serve as experimental gold standards to benchmark predictions of these properties from large-scale, electronic structure calculations. This work has demonstrated the unique capabilities of near-infrared cavity ringdown spectroscopy (NIR CRDS) to identify, characterize and monitor intermediates of key importance in complex chemical reactions. Our studies have focussed on the large family of organic peroxy radicals which are arguably themost important intermediates in combustion chemistry and many other reactions involving the oxidation of organic compounds. Our spectroscopic studies have shown that the NIR Ã - ˜X electronic spectra of the peroxy radicals allows one to differentiate among chemical species in the organic peroxy family and also determine their isomeric and conformic structure in many cases. We have clearly demonstrated this capability on saturated and unsaturated peroxy radicals and β-hydroxy peroxy radicals. In addition we have developed a unique dual wavelength CRDS apparatus specifically for the purpose of measuring absolute absorption cross section and following the reaction of chemical intermediates. The utility of the apparatus has been demonstrated by measuring the cross-section and self-reaction rate constant for ethyl peroxy.

Spectroscopic study of emission coal mineral plasma produced by laser ablation

International Nuclear Information System (INIS)

Vera, L P; Pérez, J A; Riascos, H

2014-01-01

Spectroscopic analysis of plasma produced by laser ablation of coal samples using 1064 nm radiation pulses from a Q-switched Nd:YAG on different target under air ambient, was performed. The emission of molecular band systems such as C 2 Swan System (d 3 Π g →a 3 Π u ), the First Negative System N 2 (Band head at 501,53 nm) and emission lines of the C I, C II, were investigated using the optical emission spectroscopy technique. The C 2 molecular spectra (Swan band) were analyzed to determine vibrational temperature (0,62 eV); the density and electron temperature of the plasma have been evaluated using Stark broadening and the intensity of the nitrogen emission lines N II, the found values of 1,2 eV and 2,2 x10 18 cm −3 respectively.

Application of spectroscopic techniques for the analysis of kidney stones: a pilot study

Science.gov (United States)

Shameem, K. M., Muhammed; Chawla, Arun; Bankapur, Aseefhali; Unnikrishnan, V. K.; Santhosh, C.

2016-03-01

Identification and characterization of kidney stone remains one of the important analytical tasks in the medical field. Kidney stone is a common health complication throughout the world, which may cause severe pain, obstruction and infection of urinary tract, and can lead to complete renal damage. It commonly occurs in both sexes regardless of age. Kidney stones have different composition, although each stones have a major single characteristic component. A complete understanding of a sample properties and their function can only be feasible by utilizing elemental and molecular information simultaneously. Two laser based analytical techniques; Laser Induced Breakdown spectroscopy (LIBS) and Raman spectroscopy have been used to study different types of kidney stones from different patients. LIBS and Raman spectroscopy are highly complementary spectroscopic techniques, which provide elemental and molecular information of a sample. Q-switched Nd:YAG laser at 355 nm laser having energy 17mJ per pulse at 10 Hz repetition rate was used for getting LIBS spectra. Raman measurements were carried out using a home assembled micro-Raman spectrometer. Using the recorded Raman spectra of kidney stones, we were able to differentiate different kinds of kidney stones. LIBS spectra of the same stones are showing the evidence of C, Ca, H, and O and also suggest the presence of certain pigments.

On estimating the background of remote sensing gamma-ray spectroscopic data

Energy Technology Data Exchange (ETDEWEB)

Zhu, Meng-Hua, E-mail: mhzhu@must.edu.mo

2016-10-01

In this paper, we considered the inverse count accumulation process of gamma-ray spectrum and derived an iterative filtering method to estimate the background of noisy spectroscopic data for the remote sensing observations of planetary surface. Compared with the SNIP method, the proposed method avoids the calculation of the average FWHM of the whole spectrum or the peak regions, which is an important parameter for the SNIP method. The synthetic and experimental spectra are used to validate the derived method. The results show that the proposed method can estimate the background efficiently, especially for the spectroscopic data with Compton continuum. In addition, by combining the proposed method and the SNIP method, the average FWHM can be determined easily, which can be used to validate the characteristics of detector.

Spectroscopic AC susceptibility imaging (sASI) of magnetic nanoparticles

International Nuclear Information System (INIS)

Ficko, Bradley W.; Nadar, Priyanka M.; Diamond, Solomon G.

2015-01-01

This study demonstrates a method for alternating current (AC) susceptibility imaging (ASI) of magnetic nanoparticles (mNPs) using low cost instrumentation. The ASI method uses AC magnetic susceptibility measurements to create tomographic images using an array of drive coils, compensation coils and fluxgate magnetometers. Using a spectroscopic approach in conjunction with ASI, a series of tomographic images can be created for each frequency measurement set and is termed sASI. The advantage of sASI is that mNPs can be simultaneously characterized and imaged in a biological medium. System calibration was performed by fitting the in-phase and out-of-phase susceptibility measurements of an mNP sample with a hydrodynamic diameter of 100 nm to a Brownian relaxation model (R 2 =0.96). Samples of mNPs with core diameters of 10 and 40 nm and a sample of 100 nm hydrodynamic diameter were prepared in 0.5 ml tubes. Three mNP samples were arranged in a randomized array and then scanned using sASI with six frequencies between 425 and 925 Hz. The sASI scans showed the location and quantity of the mNP samples (R 2 =0.97). Biological compatibility of the sASI method was demonstrated by scanning mNPs that were injected into a pork sausage. The mNP response in the biological medium was found to correlate with a calibration sample (R 2 =0.97, p<0.001). These results demonstrate the concept of ASI and advantages of sASI. - Highlights: • Development of an AC susceptibility imaging model. • Comparison of AC susceptibility imaging (ASI) and susceptibility magnitude imaging (SMI). • Demonstration of ASI and spectroscopic ASI (sASI) using three different magnetic nanoparticle types. • SASI scan separation of three different magnetic nanoparticles samples using 5 spectroscopic frequencies. • Demonstration of biological feasibility of sASI

Spectroscopic system for impurity measurements in the TJ-1 Tokamak of JEN

International Nuclear Information System (INIS)

Navas, G.; Zurro, B.

1982-01-01

we describe a spectroscopic system with spatial resolution capability that has been configured for plasma diagnostic in the TJ-1 Tokamak of JEN. The experimental system, based on a one meter monochromator, has been absolutely calibrated using a tungsten-halogen lamp. The calibration procedures and the absolute spectral sensitivity are presented as well as its dependence with the polarization. A simplified spectroscopic model of the radiation emitted by the intrinsic plasma impurities (C, 0, . . . ) has been developed. A one dimensional model of the temporal evolution of various ionization stages in coronal equilibrium is used to predict the electron temperature and impurity concentration. This model has been applied to experimental data from several Tokamaks. (Author) 23 refs

Optical properties of metals by spectroscopic ellipsometry

International Nuclear Information System (INIS)

Arakawa, E.T.; Inagaki, T.; Williams, M.W.

1979-01-01

The use of spectroscopic ellipsometry for the accurate determination of the optical properties of liquid and solid metals is discussed and illustrated with previously published data for Li and Na. New data on liquid Sn and Hg from 0.6 to 3.7 eV are presented. Liquid Sn is Drude-like. The optical properties of Hg deviate from the Drude expressions, but simultaneous measurements of reflectance and ellipsometric parameters yield consistent results with no evidence for vectorial surface effects

Thirty New Low-mass Spectroscopic Binaries

Science.gov (United States)

Shkolnik, Evgenya L.; Hebb, Leslie; Liu, Michael C.; Reid, I. Neill; Collier Cameron, Andrew

2010-06-01

As part of our search for young M dwarfs within 25 pc, we acquired high-resolution spectra of 185 low-mass stars compiled by the NStars project that have strong X-ray emission. By cross-correlating these spectra with radial velocity standard stars, we are sensitive to finding multi-lined spectroscopic binaries. We find a low-mass spectroscopic binary fraction of 16% consisting of 27 SB2s, 2 SB3s, and 1 SB4, increasing the number of known low-mass spectroscopic binaries (SBs) by 50% and proving that strong X-ray emission is an extremely efficient way to find M-dwarf SBs. WASP photometry of 23 of these systems revealed two low-mass eclipsing binaries (EBs), bringing the count of known M-dwarf EBs to 15. BD-22 5866, the ESB4, was fully described in 2008 by Shkolnik et al. and CCDM J04404+3127 B consists of two mid-M stars orbiting each other every 2.048 days. WASP also provided rotation periods for 12 systems, and in the cases where the synchronization time scales are short, we used P rot to determine the true orbital parameters. For those with no P rot, we used differential radial velocities to set upper limits on orbital periods and semimajor axes. More than half of our sample has near-equal-mass components (q > 0.8). This is expected since our sample is biased toward tight orbits where saturated X-ray emission is due to tidal spin-up rather than stellar youth. Increasing the samples of M-dwarf SBs and EBs is extremely valuable in setting constraints on current theories of stellar multiplicity and evolution scenarios for low-mass multiple systems. Based on observations collected at the W. M. Keck Observatory, the Canada-France-Hawaii Telescope and by the WASP Consortium. The Keck Observatory is operated as a scientific partnership between the California Institute of Technology, the University of California, and NASA, and was made possible by the generous financial support of the W. M. Keck Foundation. The CFHT is operated by the National Research Council of Canada

Raman spectroscopic studies on CeVO4 at high pressures

International Nuclear Information System (INIS)

Rao, Rekha; Garg, Alka B.; Wani, B.N.

2011-01-01

Raman scattering investigations of CeVO 4 at high pressures is reported. Polycrystalline CeVO 4 was prepared by solid state reaction of CeO 2 and V 2 O 5 . High pressure Raman spectroscopic measurements were carried out as per experimental details given

Near-Infrared Spectroscopic Study of Chlorite Minerals

Directory of Open Access Journals (Sweden)

Min Yang

2018-01-01

Full Text Available The mineral chemistry of twenty chlorite samples from the United States Geological Survey (USGS spectral library and two other regions, having a wide range of Fe and Mg contents and relatively constant Al and Si contents, was studied via infrared (IR spectroscopy, near-infrared (NIR spectroscopy, and X-ray fluorescence (XRF analysis. Five absorption features of the twenty samples near 4525, 4440, 4361, 4270, and 4182 cm−1 were observed, and two diagnostic features at 4440 and 4280 cm−1 were recognized. Assignments of the two diagnostic features were made for two combination bands (ν+δAlAlO−OH and ν+δSiAlO−OH by regression with IR fundamental absorptions. Furthermore, the determinant factors of the NIR band position were found by comparing the band positions with relative components. The results showed that Fe/(Fe + Mg values are negatively correlated with the two NIR combination bands. The findings provide an interpretation of the NIR band formation and demonstrate a simple way to use NIR spectroscopy to discriminate between chlorites with different components. More importantly, spectroscopic detection of mineral chemical variations in chlorites provides geologists with a tool with which to collect information on hydrothermal alteration zones from hyperspectral-resolution remote sensing data.

A comparison of Hipparcos parallaxes with planetary nebulae spectroscopic distances

NARCIS (Netherlands)

Pottasch, [No Value; Acker, A

1998-01-01

The Hipparcos satellite has measured the parallax of a small sample of planetary nebulae. In this paper we consider the results for 3 planetary nebulae (PN) for which spectroscopic distances have also been determined from stellar gravities. These gravities in turn have been derived from profile

Characterization of ion-implanted aluminum and iron by spectroscopic ellipsometry

International Nuclear Information System (INIS)

Brodkin, J.S.; Franzen, W.; Culbertson, R.J.

1990-01-01

The change in the optical constants of aluminum alloy and iron samples caused by implantation with nitrogen and chromium ions has been investigated by spectroscopic ellipsometry. The objective is to develop a method for simple, non-destructive characterization of ion-implanted metals. 5 refs., 6 figs

Mg-doped hydroxyapatite nanoplates for biomedical applications: A surfactant assisted microwave synthesis and spectroscopic investigations

International Nuclear Information System (INIS)

Mishra, Vijay Kumar; Bhattacharjee, Birendra Nath; Parkash, Om; Kumar, Devendra; Rai, Shyam Bahadur

2014-01-01

Highlights: • Microwave irradiation technique: employed for the synthesis of Mg-HAp nanoplates. • Surfactant (EDTA) assisted synthesis of Mg-HAp. • FT-IR and Raman analysis of functional groups of Mg-HAp. - Abstract: Nanoplates of Mg doped hydroxyapatite (Mg-HAp) were derived successfully and rapidly via microwave irradiation technique. Hydroxyapatite (HAp) is the hard tissues and main inorganic component in mammals. Different nanostructures of HAp exist in different parts of human bone but nanorods are very common due to its intrinsic nature to grow in rode-like structure under physiological as well as under applied ambient conditions in laboratory. On the addition of Mg at very low level (0.06 mol%) in pure HAp results the formation of 2-D plate-like nanostructures rather than rod-like which is the matter of interest. In this attempt our efforts have been focused on the study of effect of Mg incorporation on structural and spectroscopic properties of HAp prepared via microwave irradiation technique. This technique is preferred due to several advantages viz. very fast as well as homogeneous heating, time/energy saving and eco-friendliness. The calcium nitrate tetrahydrate (Ca(NO 3 ) 2 ⋅4H 2 O)) as a source of calcium, magnesium nitrate hexahydrate (Mg(NO 3 ) 2 ⋅6H 2 O) as a source of magnesium, disodium hydrogen phosphate dihydrate (NaH 2 PO 4 ⋅2H 2 O) as a source of phosphorous and sodium ethylene diamine tetra acetate (NaEDTA) as a surfactant were used as starting reagents. Sodium hydroxide (NaOH) pellets were employed to adjust the pH value of final solution. The solution of fixed pH value was kept into the microwave oven generating waves of frequency 2.45 GHz (water absorption frequency) and power 750 W for 8 min. The precipitate thus obtained was washed, centrifuged and then dried at 100 °C for 2 h. Dried powder was then calcined at 700 °C for 2 h. The bright white powder thus obtained was characterized structurally using X-ray diffraction and

Mg-doped hydroxyapatite nanoplates for biomedical applications: A surfactant assisted microwave synthesis and spectroscopic investigations

Energy Technology Data Exchange (ETDEWEB)

Mishra, Vijay Kumar [Department of Physics, Faculty of Science, Banaras Hindu University, Varanasi 221005 (India); Bhattacharjee, Birendra Nath; Parkash, Om [Department of Ceramic Engineering, Indian Institute of Technology, Banaras Hindu University, Varanasi 221005 (India); Kumar, Devendra, E-mail: devendra.cer@iitbhu.ac.in [Department of Ceramic Engineering, Indian Institute of Technology, Banaras Hindu University, Varanasi 221005 (India); Rai, Shyam Bahadur, E-mail: sbrai49@yahoo.co.in [Department of Physics, Faculty of Science, Banaras Hindu University, Varanasi 221005 (India)

2014-11-25

Highlights: • Microwave irradiation technique: employed for the synthesis of Mg-HAp nanoplates. • Surfactant (EDTA) assisted synthesis of Mg-HAp. • FT-IR and Raman analysis of functional groups of Mg-HAp. - Abstract: Nanoplates of Mg doped hydroxyapatite (Mg-HAp) were derived successfully and rapidly via microwave irradiation technique. Hydroxyapatite (HAp) is the hard tissues and main inorganic component in mammals. Different nanostructures of HAp exist in different parts of human bone but nanorods are very common due to its intrinsic nature to grow in rode-like structure under physiological as well as under applied ambient conditions in laboratory. On the addition of Mg at very low level (0.06 mol%) in pure HAp results the formation of 2-D plate-like nanostructures rather than rod-like which is the matter of interest. In this attempt our efforts have been focused on the study of effect of Mg incorporation on structural and spectroscopic properties of HAp prepared via microwave irradiation technique. This technique is preferred due to several advantages viz. very fast as well as homogeneous heating, time/energy saving and eco-friendliness. The calcium nitrate tetrahydrate (Ca(NO{sub 3}){sub 2}⋅4H{sub 2}O)) as a source of calcium, magnesium nitrate hexahydrate (Mg(NO{sub 3}){sub 2}⋅6H{sub 2}O) as a source of magnesium, disodium hydrogen phosphate dihydrate (NaH{sub 2}PO{sub 4}⋅2H{sub 2}O) as a source of phosphorous and sodium ethylene diamine tetra acetate (NaEDTA) as a surfactant were used as starting reagents. Sodium hydroxide (NaOH) pellets were employed to adjust the pH value of final solution. The solution of fixed pH value was kept into the microwave oven generating waves of frequency 2.45 GHz (water absorption frequency) and power 750 W for 8 min. The precipitate thus obtained was washed, centrifuged and then dried at 100 °C for 2 h. Dried powder was then calcined at 700 °C for 2 h. The bright white powder thus obtained was characterized

On-line data processing apparatus for spectroscopic measurements of atomic uranium

International Nuclear Information System (INIS)

Miron, E.; Levin, L.A.; Erez, G; Baumatz, D; Goren, I.; Shpancer, I.

1977-01-01

A computer-based apparatus for on-line spectroscopic measurements of atomic uranium is described. The system is capable of enhancing the signal-to-noise ratio by averaging, and performing calculations. Computation flow charts and programs are included

Charged particle reaction studies on /sup 14/C. [Spectroscopic factors

Energy Technology Data Exchange (ETDEWEB)

Cecil, F E; Shepard, J R; Anderson, R E; Peterson, R J; Kaczkowski, P [Colorado Univ., Boulder (USA). Nuclear Physics Lab.

1975-12-22

The reactions /sup 14/C(p,d), (d,d') and (d,p) have been measured for E/sub p/ = 27 MeV and E/sub d/ = 17 MeV. The (d,d') and (d,p) reactions were studied between theta/sub lab/ = 15/sup 0/ and 85/sup 0/; the (p,d) reactions, between theta/sub lab/ = 5/sup 0/ and 40/sup 0/. The /sup 14/C deformation parameters were deduced from the deuteron inelastic scattering and found to agree with deformations measured in nearby doubly even nuclei. The spectroscopic factors deduced from the (p,d) reaction allowed a /sup 14/C ground-state wave function to be deduced which compares favorably with a theoretically deduced wave function. The (p,d) and (d,p) spectroscopic factors are consistent. The implications of our /sup 14/C ground-state wave function regarding the problem of the /sup 14/C hindered beta decay are discussed.

Time-Resolved Emission Spectroscopic Study of Laser-Induced Steel Plasmas

International Nuclear Information System (INIS)

Shah, M. L.; Pulhani, A. K.; Suri, B. M.; Gupta, G. P.

2013-01-01

Laser-induced steel plasma is generated by focusing a Q-switched Nd:YAG visible laser (532 nm wavelength) with an irradiance of ∼ 1 × 10 9 W/cm 2 on a steel sample in air at atmospheric pressure. An Echelle spectrograph coupled with a gateable intensified charge-coupled detector is used to record the plasma emissions. Using time-resolved spectroscopic measurements of the plasma emissions, the temperature and electron number density of the steel plasma are determined for many times of the detector delay. The validity of the assumption by the spectroscopic methods that the laser-induced plasma (LIP) is optically thin and is also in local thermodynamic equilibrium (LTE) has been evaluated for many delay times. From the temporal evolution of the intensity ratio of two Fe I lines and matching it with its theoretical value, the delay times where the plasma is optically thin and is also in LTE are found to be 800 ns, 900 ns and 1000 ns.

Far-infrared Spectroscopic Characterization of Anti-vinyl Alcohol

Science.gov (United States)

Bunn, Hayley; Soliday, Rebekah M.; Sumner, Isaiah; Raston, Paul L.

2017-09-01

We report a detailed analysis of the high-resolution far-infrared spectrum of anti-vinyl alcohol, which has been previously identified toward Sagittarius B2(N). The ν 15 OH torsional fundamental investigated here is more than 200 cm-1 removed from the next nearest vibration, making it practically unperturbed and ideal to help refine the ground state rotational constants that were previously determined from 25 microwave lines. We assigned 1335 lines within the ν 15 fundamental centered at 261.5512 cm-1, with J and K a ranges of 1-59 and 0-16, respectively. The microwave and far-infrared line positions were fit with Watson-type A- and S-reduced Hamiltonians, with the inclusion of quartic and select sextic distortion terms. This resulted in a significant refinement of the ground state constants, in addition to the determination of the {ν }15=1 state constants for the first time. The spectroscopic parameters are in good agreement with the results from anharmonic coupled-cluster calculations, and should be useful in searches for rotationally and/or vibrationally warm anti-vinyl alcohol in interstellar molecular clouds.

Mock Quasar-Lyman-α forest data-sets for the SDSS-III Baryon Oscillation Spectroscopic Survey

Energy Technology Data Exchange (ETDEWEB)

Bautista, Julian E.; Busca, Nicolas G. [APC, Université Paris Diderot-Paris 7, CNRS/IN2P3, CEA, Observatoire de Paris, 10, rue A. Domon and L. Duquet, Paris (France); Bailey, Stephen; Font-Ribera, Andreu; Schlegel, David [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA (United States); Pieri, Matthew M. [Aix Marseille Université, CNRS, LAM (Laboratoire d' Astrophysique de Marseille) UMR 7326, 38 rue Frédéric Joliot-Curie, 13388, Marseille (France); Miralda-Escudé, Jordi; Gontcho, Satya Gontcho A. [Institut de Ciències del Cosmos, Universitat de Barcelona/IEEC, 1 Martí i Franquès, Barcelona 08028, Catalonia (Spain); Palanque-Delabrouille, Nathalie; Rich, James; Goff, Jean Marc Le [CEA, Centre de Saclay, Irfu/SPP, D128, F-91191 Gif-sur-Yvette (France); Dawson, Kyle [Department of Physics and Astronomy, University of Utah, 115 S 100 E, RM 201, Salt Lake City, UT 84112 (United States); Feng, Yu; Ho, Shirley [McWilliams Center for Cosmology, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213 (United States); Ge, Jian [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611-2055 (United States); Noterdaeme, Pasquier; Pâris, Isabelle [Université Paris 6 et CNRS, Institut d' Astrophysique de Paris, 98bis blvd. Arago, 75014 Paris (France); Rossi, Graziano, E-mail: bautista@astro.utah.edu [Department of Astronomy and Space Science, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 143-747 (Korea, Republic of)

2015-05-01

We describe mock data-sets generated to simulate the high-redshift quasar sample in Data Release 11 (DR11) of the SDSS-III Baryon Oscillation Spectroscopic Survey (BOSS). The mock spectra contain Lyα forest correlations useful for studying the 3D correlation function including Baryon Acoustic Oscillations (BAO). They also include astrophysical effects such as quasar continuum diversity and high-density absorbers, instrumental effects such as noise and spectral resolution, as well as imperfections introduced by the SDSS pipeline treatment of the raw data. The Lyα forest BAO analysis of the BOSS collaboration, described in Delubac et al. 2014, has used these mock data-sets to develop and cross-check analysis procedures prior to performing the BAO analysis on real data, and for continued systematic cross checks. Tests presented here show that the simulations reproduce sufficiently well important characteristics of real spectra. These mock data-sets will be made available together with the data at the time of the Data Release 11.

A LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) for biological tissue impedance analysis and equivalent circuit modelling

KAUST Repository

Bera, Tushar Kanti

2016-12-05

Under an alternating electrical signal, biological tissues produce a complex electrical bioimpedance that is a function of tissue composition and applied signal frequencies. By studying the bioimpedance spectra of biological tissues over a wide range of frequencies, we can noninvasively probe the physiological properties of these tissues to detect possible pathological conditions. Electrical impedance spectroscopy (EIS) can provide the spectra that are needed to calculate impedance parameters within a wide range of frequencies. Before impedance parameters can be calculated and tissue information extracted, impedance spectra should be processed and analyzed by a dedicated software program. National Instruments (NI) Inc. offers LabVIEW, a fast, portable, robust, user-friendly platform for designing dataanalyzing software. We developed a LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) to analyze the electrical impedance spectra for tissue characterization in medical, biomedical and biological applications. Here, we test, calibrate and evaluate the performance of LEBISDI on the impedance data obtained from simulation studies as well as the practical EIS experimentations conducted on electronic circuit element combinations and the biological tissue samples. We analyze the Nyquist plots obtained from the EIS measurements and compare the equivalent circuit parameters calculated by LEBISDI with the corresponding original circuit parameters to assess the accuracy of the program developed. Calibration studies show that LEBISDI not only interpreted the simulated and circuitelement data accurately, but also successfully interpreted tissues impedance data and estimated the capacitive and resistive components produced by the compositions biological cells. Finally, LEBISDI efficiently calculated and analyzed variation in bioimpedance parameters of different tissue compositions, health and temperatures. LEBISDI can also be used for human tissue

A LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) for biological tissue impedance analysis and equivalent circuit modelling

KAUST Repository

Bera, Tushar Kanti; Jampana, Nagaraju; Lubineau, Gilles

2016-01-01

Under an alternating electrical signal, biological tissues produce a complex electrical bioimpedance that is a function of tissue composition and applied signal frequencies. By studying the bioimpedance spectra of biological tissues over a wide range of frequencies, we can noninvasively probe the physiological properties of these tissues to detect possible pathological conditions. Electrical impedance spectroscopy (EIS) can provide the spectra that are needed to calculate impedance parameters within a wide range of frequencies. Before impedance parameters can be calculated and tissue information extracted, impedance spectra should be processed and analyzed by a dedicated software program. National Instruments (NI) Inc. offers LabVIEW, a fast, portable, robust, user-friendly platform for designing dataanalyzing software. We developed a LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) to analyze the electrical impedance spectra for tissue characterization in medical, biomedical and biological applications. Here, we test, calibrate and evaluate the performance of LEBISDI on the impedance data obtained from simulation studies as well as the practical EIS experimentations conducted on electronic circuit element combinations and the biological tissue samples. We analyze the Nyquist plots obtained from the EIS measurements and compare the equivalent circuit parameters calculated by LEBISDI with the corresponding original circuit parameters to assess the accuracy of the program developed. Calibration studies show that LEBISDI not only interpreted the simulated and circuitelement data accurately, but also successfully interpreted tissues impedance data and estimated the capacitive and resistive components produced by the compositions biological cells. Finally, LEBISDI efficiently calculated and analyzed variation in bioimpedance parameters of different tissue compositions, health and temperatures. LEBISDI can also be used for human tissue

One- and two-dimensional infrared spectroscopic studies of solution-phase homogeneous catalysis and spin-forbidden reactions

Energy Technology Data Exchange (ETDEWEB)

Sawyer, Karma Rae [Univ. of California, Berkeley, CA (United States)

2008-12-01

Understanding chemical reactions requires the knowledge of the elementary steps of breaking and making bonds, and often a variety of experimental techniques are needed to achieve this goal. The initial steps occur on the femto- through picosecond time-scales, requiring the use of ultrafast spectroscopic methods, while the rate-limiting steps often occur more slowly, requiring alternative techniques. Ultrafast one and two-dimensional infrared and step-scan FTIR spectroscopies are used to investigate the photochemical reactions of four organometallic complexes. The analysis leads to a detailed understanding of mechanisms that are general in nature and may be applicable to a variety of reactions.

SDSS-IV MaNGA: the spectroscopic discovery of strongly lensed galaxies

Science.gov (United States)

Talbot, Michael S.; Brownstein, Joel R.; Bolton, Adam S.; Bundy, Kevin; Andrews, Brett H.; Cherinka, Brian; Collett, Thomas E.; More, Anupreeta; More, Surhud; Sonnenfeld, Alessandro; Vegetti, Simona; Wake, David A.; Weijmans, Anne-Marie; Westfall, Kyle B.

2018-06-01

We present a catalogue of 38 spectroscopically detected strong galaxy-galaxy gravitational lens candidates identified in the Sloan Digital Sky Survey IV (SDSS-IV). We were able to simulate narrow-band images for eight of them demonstrating evidence of multiple images. Two of our systems are compound lens candidates, each with two background source-planes. One of these compound systems shows clear lensing features in the narrow-band image. Our sample is based on 2812 galaxies observed by the Mapping Nearby Galaxies at APO (MaNGA) integral field unit (IFU). This Spectroscopic Identification of Lensing Objects (SILO) survey extends the methodology of the Sloan Lens ACS Survey (SLACS) and BOSS Emission-Line Survey (BELLS) to lower redshift and multiple IFU spectra. We searched ˜1.5 million spectra, of which 3065 contained multiple high signal-to-noise ratio background emission-lines or a resolved [O II] doublet, that are included in this catalogue. Upon manual inspection, we discovered regions with multiple spectra containing background emission-lines at the same redshift, providing evidence of a common source-plane geometry which was not possible in previous SLACS and BELLS discovery programs. We estimate more than half of our candidates have an Einstein radius ≳ 1.7 arcsec, which is significantly greater than seen in SLACS and BELLS. These larger Einstein radii produce more extended images of the background galaxy increasing the probability that a background emission-line will enter one of the IFU spectroscopic fibres, making detection more likely.

Facility at CIRUS reactor for thermal neutron induced prompt γ-ray spectroscopic studies

International Nuclear Information System (INIS)

Biswas, D.C.; Danu, L.S.; Mukhopadhyay, S.; Kinage, L.A.; Prashanth, P.N.; Goswami, A.; Sahu, A.K.; Shaikh, A.M.; Chatterjee, A.; Choudhury, R.K.; Kailas, S.

2013-01-01

A facility for prompt γ-ray spectroscopic studies using thermal neutrons from a radial beam line of Canada India Research Utility Services (CIRUS) reactor, Bhabha Atomic Research Centre (BARC), has been developed. To carry out on-line spectroscopy experiments, two clover germanium detectors were used for the measurement of prompt γ rays. For the first time, the prompt γ–γ coincidence technique has been used to study the thermal neutron induced fission fragment spectroscopy (FFS) in 235 U(n th , f). Using this facility, experiments have also been carried out for on-line γ-ray spectroscopic studies in 113 Cd(n th , γ) reaction

Investigation and measures to noise on spectroscopic measurement system in JT-60U

International Nuclear Information System (INIS)

Nagaya, Susumu; Kubo, Hirotaka; Sugie, Tatsuo; Onizawa, Masami; Kawai, Isao; Nakata, Hisao.

1997-11-01

Breakdown of a negative-ion-based neutral beam injection (N-NBI) has caused noise trouble to several systems. The control circuit of a spectroscopic measurement system had not well worked because of the noise. The noise has been measured by an optical-fiber isolation system during operation of JT-60U. The amplitude and the frequency were 15-18 V and 15 MHz respectively. The transmission noise has been reduced by putting ferrite cores to all cables connecting with the control circuits. As a result, the trouble with the spectroscopic measurement system has completely been solved. Adding condensers and resistors to the circuit was not effective to reduce the noise. (author)

Method and apparatus for scientific analysis under low temperature vacuum conditions

Science.gov (United States)

Winefordner, James D.; Jones, Bradley T.

1990-01-01

A method and apparatus for scientific analysis of a sample under low temperature vacuum conditions uses a vacuum chamber with a conveyor belt disposed therein. One end of the conveyor belt is a cool end in thermal contact with the cold stage of a refrigerator, whereas the other end of the conveyor belt is a warm end spaced from the refrigerator. A septum allows injection of a sample into the vacuum chamber on top of the conveyor belt for spectroscopic or other analysis. The sample freezes on the conveyor belt at the cold end. One or more windows in the vacuum chamber housing allow spectroscopic analysis of the sample. Following the spectroscopic analysis, the conveyor belt may be moved such that the sample moves toward the warm end of the conveyor belt where upon it evaporates, thereby cleaning the conveyor belt. Instead of injecting the sample by way of a septum and use of a syringe and needle, the present device may be used in series with capillary-column gas chromatography or micro-bore high performance liquid chromatography.

Analysis of the spectroscopic characteristics on the binding interaction between tosufloxacin and bovine lactoferrin

International Nuclear Information System (INIS)

Guo Ming; Zhang Luying; Lue Weijun; Cao Huaru

2011-01-01

The interaction between tosufloxacin (TELX) and bovine lactoferrin (BLF) in aqueous solution was analyzed by fluorescence spectroscopy and absorbance spectra. The binding parameters and energy-transfer efficiency parameters were determined and the mechanism of interaction was discussed. The effect of tosufloxacin acting on the BLF's conformation was detected and the unfolding procedure of BLF induced by tosufloxacin was explored by 'fluorescence phase diagram'. Following experimental data of fluorescence polarization values P and r, the saturation characteristic of such kind of binding reaction was observed for the first time. The interaction between tosufloxacin and BLF influenced by Ni 2+ and Co 2+ were also preliminarily explored in this work. - Research Highlights: →In this paper, a new saturation spectroscopic characteristic of non-covalent binding reaction is proposed. The saturated character of interaction of tosufloxacin binding with bovine lactoferrin is firstly observed by fluorescence polarization spectroscopy. →The unfolding procedure of bovine lactoferrin induced by drug ligand is analyzed by 'fluorescence phase diagram', and it is quantitatively characterized. →The binding parameters and energy-transfer efficiency parameters of bovine lactoferrin-tosufloxacin/tosufloxacin-Co 2+ (Ni 2+ ) system are determined and the mechanism of interaction is discussed.

Multidimensional Raman spectroscopic signature of sweat and its potential application to forensic body fluid identification.

Science.gov (United States)

Sikirzhytski, Vitali; Sikirzhytskaya, Aliaksandra; Lednev, Igor K

2012-03-09

This proof-of-concept study demonstrated the potential of Raman microspectroscopy for nondestructive identification of traces of sweat for forensic purposes. Advanced statistical analysis of Raman spectra revealed that dry sweat was intrinsically heterogeneous, and its biochemical composition varies significantly with the donor. As a result, no single Raman spectrum could adequately represent sweat traces. Instead, a multidimensional spectroscopic signature of sweat was built that allowed for the presentation of any single experimental spectrum as a linear combination of two fluorescent backgrounds and three Raman spectral components dominated by the contribution from lactate, lactic acid, urea and single amino acids. Copyright © 2011 Elsevier B.V. All rights reserved.

Single hole spectroscopic strength in 98Ru through the 99Ru(d,t) reaction

International Nuclear Information System (INIS)

Rodrigues, M.R.D.; Borello-Lewin, T.; Horodynski-Matsushigue, L.B.; Duarte, J.L.M.; Rodrigues, C.L.; Barbosa, M.D.L.; Silva, G.B. da; Ukita, G.M.

2002-01-01

The 99 Ru(d,t) 98 Ru reaction was measured for the first time at 16 MeV incident energy with the Sao Paulo Pelletron-Enge-spectrograph facility employing the nuclear emulsion technique. In all, up to 3.5 MeV, 23 levels were detected, eight of them new; angular distributions are presented for all of them. Least squares fits of distorted wave Born approximation one-neutron pickup predictions to the rather well structured experimental angular distributions enabled the determination of l transfers and of the corresponding spectroscopic factors for 19 of these states, some being tentative attributions. Only transfers of l=0, 2, and 4 were observed. Several states were populated through single l transfers. A pure l=2 transfer is associated with the 2 1 + level and with several other states which are considered collective, as well as with the (4 + ) state at 2.277 MeV, which presents the highest spectroscopic strength. Considering five valence neutrons above the N=50 core, only 41% of the spectroscopic strength expected for 99 Ru was detected

THE SPECTROSCOPIC DIVERSITY OF TYPE Ia SUPERNOVAE

International Nuclear Information System (INIS)

Blondin, S.; Matheson, T.; Kirshner, R. P.; Mandel, K. S.; Challis, P.; Berlind, P.; Calkins, M.; Garnavich, P. M.; Jha, S. W.; Modjaz, M.; Riess, A. G.; Schmidt, B. P.

2012-01-01

We present 2603 spectra of 462 nearby Type Ia supernovae (SNe Ia), including 2065 previously unpublished spectra, obtained during 1993-2008 through the Center for Astrophysics Supernova Program. There are on average eight spectra for each of the 313 SNe Ia with at least two spectra. Most of the spectra were obtained with the FAST spectrograph at the Fred Lawrence Whipple Observatory 1.5 m telescope and reduced in a consistent manner, making this data set well suited for studies of SN Ia spectroscopic diversity. Using additional data from the literature, we study the spectroscopic and photometric properties of SNe Ia as a function of spectroscopic class using the classification schemes of Branch et al. and Wang et al. The width-luminosity relation appears to be steeper for SNe Ia with broader lines, although the result is not statistically significant with the present sample. Based on the evolution of the characteristic Si II λ6355 line, we propose improved methods for measuring velocity gradients, revealing a larger range than previously suspected, from ∼0 to ∼400 km s −1 day −1 considering the instantaneous velocity decline rate at maximum light. We find a weaker and less significant correlation between Si II velocity and intrinsic B – V color at maximum light than reported by Foley et al., owing to a more comprehensive treatment of uncertainties and host galaxy dust. We study the extent of nuclear burning and the presence of unburnt carbon in the outermost layers of the ejecta and report new detections of C II λ6580 in 23 early-time SN Ia spectra. The frequency of C II detections is not higher in SNe Ia with bluer colors or narrower light curves, in conflict with the recent results of Thomas et al. Based on nebular spectra of 27 SNe Ia, we find no relation between the FWHM of the iron emission feature at ∼4700 Å and Δm 15 (B) after removing the two low-luminosity SN 1986G and SN 1991bg, suggesting that the peak luminosity is not strongly dependent

SINGLE-LINED SPECTROSCOPIC BINARY STAR CANDIDATES IN THE RAVE SURVEY

International Nuclear Information System (INIS)

Matijevic, G.; Zwitter, T.; Bienayme, O.; Siebert, A.; Watson, F. G.; Bland-Hawthorn, J.; Parker, Q. A.; Freeman, K. C.; Gilmore, G.; Grebel, E. K.; Helmi, A.; Munari, U.; Siviero, A.; Navarro, J. F.; Reid, W.; Seabroke, G. M.; Steinmetz, M.; Williams, M.; Wyse, R. F. G.

2011-01-01

Repeated spectroscopic observations of stars in the RAdial Velocity Experiment (RAVE) database are used to identify and examine single-lined binary (SB1) candidates. The RAVE latest internal database (VDR3) includes radial velocities, atmospheric parameters, and other parameters for approximately a quarter of a million different stars with slightly less than 300,000 observations. In the sample of ∼20,000 stars observed more than once, 1333 stars with variable radial velocities were identified. Most of them are believed to be SB1 candidates. The fraction of SB1 candidates among stars with several observations is between 10% and 15% which is the lower limit for binarity among RAVE stars. Due to the distribution of time spans between the re-observation that is biased toward relatively short timescales (days to weeks), the periods of the identified SB1 candidates are most likely in the same range. Because of the RAVE's narrow magnitude range most of the dwarf candidates belong to the thin Galactic disk while the giants are part of the thick disk with distances extending to up to a few kpc. The comparison of the list of SB1 candidates to the VSX catalog of variable stars yielded several pulsating variables among the giant population with radial velocity variations of up to few tens of km s -1 . There are 26 matches between the catalog of spectroscopic binary orbits (S B 9 ) and the whole RAVE sample for which the given periastron time and the time of RAVE observation were close enough to yield a reliable comparison. RAVE measurements of radial velocities of known spectroscopic binaries are consistent with their published radial velocity curves.

Synthesis and spectroscopic properties of transfermium isotopes with Z = 105, 106 and 107

Energy Technology Data Exchange (ETDEWEB)

Streicher, B [Comenius University, Faculty of Mathematics, Physics and Informatics, Department of Nuclear Physics and Biopgysics, 84218 Bratislava (Slovakia)

2006-07-01

The quest for production of new elements has been on for several decades. On the way up the ladder of nuclear chart the systematic research of nuclear properties of elements in transfermium region has been severely overlooked. This drawback is being rectified in past few years by systematic synthesis of especially even-even and odd-A isotopes of these elements. This work proceeds forward also with major contribution of velocity filter SHIP, placed at GSI, Darmstadt. This experimental device represents a unique possibility due to high (up to 1 p{mu}A) beam currents provided by UNILAC accelerator and advancing detection systems to study by means of decay spectroscopy the nuclear structure of isotopes for the elements, possibly up to proton number Z = 110. As the low lying single-particle levels are especially determined by the unpaired nucleon, the odd mass nuclei provide a valuable source of information about the nuclear structure. Such results can be directly compared with the predictions of the calculations based on macroscopic-microscopic model of nuclear matter, thus proving an unambiguous test of the correctness of present models and their power to predict nuclear properties towards yet unknown regions. This work concentrates on the spectroscopic analysis of few of such nuclei. Namely it deals with isotopes {sup 261}Sg and {sup 257}Rf with one unpaired neutron, as well as isotopes {sup 257}Db and {sup 253}Lr with one unpaired proton configuration. Moreover, the analysis of odd-odd nuclei of the the decay sequence {sup 262}Bg {yields} {sup 258}Db {yields} {sup 254}Lr {yields} produced in various experiments at SHIP is discussed in detail. Exhaustive spectroscopic analysis of these data is provided, revealing new information on {alpha}, {beta}, EC and SF decay modes of these very heavy isotopes, and deepening the knowledge of the low lying single-particle level structure. Outcomes resulting from the comparison with the systematics of experimentally derived

Intermolecular interaction of fosinopril with bovine serum albumin (BSA): The multi-spectroscopic and computational investigation.

Science.gov (United States)

Zhou, Kai-Li; Pan, Dong-Qi; Lou, Yan-Yue; Shi, Jie-Hua

2018-04-16

The intermolecular interaction of fosinopril, an angiotensin converting enzyme inhibitor with bovine serum albumin (BSA), has been investigated in physiological buffer (pH 7.4) by multi-spectroscopic methods and molecular docking technique. The results obtained from fluorescence and UV absorption spectroscopy revealed that the fluorescence quenching mechanism of BSA induced by fosinopril was mediated by the combined dynamic and static quenching, and the static quenching was dominant in this system. The binding constant, K b , value was found to lie between 2.69 × 10 3 and 9.55 × 10 3  M -1 at experimental temperatures (293, 298, 303, and 308 K), implying the low or intermediate binding affinity between fosinopril and BSA. Competitive binding experiments with site markers (phenylbutazone and diazepam) suggested that fosinopril preferentially bound to the site I in sub-domain IIA on BSA, as evidenced by molecular docking analysis. The negative sign for enthalpy change (ΔH 0 ) and entropy change (ΔS 0 ) indicated that van der Waals force and hydrogen bonds played important roles in the fosinopril-BSA interaction, and 8-anilino-1-naphthalenesulfonate binding assay experiments offered evidence of the involvements of hydrophobic interactions. Moreover, spectroscopic results (synchronous fluorescence, 3-dimensional fluorescence, and Fourier transform infrared spectroscopy) indicated a slight conformational change in BSA upon fosinopril interaction. Copyright © 2018 John Wiley & Sons, Ltd.

Spectroscopic characterization of galaxy clusters in RCS-1: spectroscopic confirmation, redshift accuracy, and dynamical mass-richness relation

Science.gov (United States)

Gilbank, David G.; Barrientos, L. Felipe; Ellingson, Erica; Blindert, Kris; Yee, H. K. C.; Anguita, T.; Gladders, M. D.; Hall, P. B.; Hertling, G.; Infante, L.; Yan, R.; Carrasco, M.; Garcia-Vergara, Cristina; Dawson, K. S.; Lidman, C.; Morokuma, T.

2018-05-01

We present follow-up spectroscopic observations of galaxy clusters from the first Red-sequence Cluster Survey (RCS-1). This work focuses on two samples, a lower redshift sample of ˜30 clusters ranging in redshift from z ˜ 0.2-0.6 observed with multiobject spectroscopy (MOS) on 4-6.5-m class telescopes and a z ˜ 1 sample of ˜10 clusters 8-m class telescope observations. We examine the detection efficiency and redshift accuracy of the now widely used red-sequence technique for selecting clusters via overdensities of red-sequence galaxies. Using both these data and extended samples including previously published RCS-1 spectroscopy and spectroscopic redshifts from SDSS, we find that the red-sequence redshift using simple two-filter cluster photometric redshifts is accurate to σz ≈ 0.035(1 + z) in RCS-1. This accuracy can potentially be improved with better survey photometric calibration. For the lower redshift sample, ˜5 per cent of clusters show some (minor) contamination from secondary systems with the same red-sequence intruding into the measurement aperture of the original cluster. At z ˜ 1, the rate rises to ˜20 per cent. Approximately ten per cent of projections are expected to be serious, where the two components contribute significant numbers of their red-sequence galaxies to another cluster. Finally, we present a preliminary study of the mass-richness calibration using velocity dispersions to probe the dynamical masses of the clusters. We find a relation broadly consistent with that seen in the local universe from the WINGS sample at z ˜ 0.05.

Mass spectroscopic analysis of atmospheric particulate matter

International Nuclear Information System (INIS)

Wippel, R.

1997-02-01

Particulate matter (PM) in the atmosphere vary greatly in origin, in their physical and chemical properties and their effects on climate, atmospheric chemistry and health. Aerosol particles with an aerodynamic diameter less than two μm can enter the respiratory tract of humans when inhaled. Bulk analysis of ambient dust particles was performed using an inductively coupled plasma mass spectrometer (ICP-MS). The size-fractionated collected samples were analyzed after a leaching procedure that simulates the solution reactions occurring in the lungs. A disadvantage of bulk analysis is that it gives no information about the distribution of a certain element within the particles under investigation. A Laser-Microprobe-Mass-Analyzer (LAMMA-500) was used to obtain this information. At sampling sites in Austria and in Zimbabwe, Africa, single particles were sampled using a self-made impactor. One of the final aims in environmental analysis is to successfully apply receptor models that relate the chemical and physical properties of a receptor site to a source. The knowledge of the sources of atmospheric particulate matter is essential for environmental policy makers as well as for epidemiological studies. Artificial neural networks (ANN) have a remarkable ability to handle LAMMA-data. Three ANNs were used as a pattern recognition tool for LAMMA mass spectral data: a back-propagation net, a Kohonen network,and a counter-propagation net. Standard source profiles from the United States Environmental Protection Agency were used as training and test data of the different nets. The elemental patterns of the sum of 100 mass spectra of fine dust particles were presented to the trained nets and satisfactory recognition (> 80 %) was obtained. (author)

Spectroscopic information from (3He, 7Be) reaction on 12C and 24Mg

International Nuclear Information System (INIS)

Rahman, Md.A.; Sen Gupta, H.M.

1986-01-01

The reaction ( 3 He, 7 Be) on 12 C and 24 Mg has been analysed using four discrete potential families for 7 Be channel and one discrete potential family for 3 He channel to extract alpha spectroscopic factors. It is shown that the relative spectroscopic factors are reliable if they are calculated staying within one potential family (S( 24 Mg/ 12 C) approx. 0.12). But, changing the potential family between 12 C and 24 Mg, one obtains the extreme cases, such as S( 24 Mg/ 12 C) = 0.025 and 0.51, i.e. 1:20

Proton MR spectroscopic features of liver cirrhosis : comparing with normal liver

International Nuclear Information System (INIS)

Cho, Soon Gu; Choi, Won; Kim, Young Soo; Kim, Mi Young; Jee, Keum Nahn; Lee, Kyung Hee; Suh, Chang Hae

2000-01-01

detected at 3.9-4.1 ppm with unknown nature. Mean and standard deviation of area ratio of the unknown peak to lipid peak in proton MR spectra of liver cirrhosis was 0.1504 ± 0.0335. Proton MR spectra of liver cirrhosis revealed decreased intensity of lipid with statistical significance compared with that of normal liver, and peak at 3.9-4 ppm with unknown nature. In conclusion, liver cirrhosis can be diagnosed non-invasively by the analysis of observed proton MR spectroscopic features. (author)

Nanoparticles displacement analysis using optical coherence tomography

Science.gov (United States)

StrÄ kowski, Marcin R.; Kraszewski, Maciej; StrÄ kowska, Paulina

2016-03-01

Optical coherence tomography (OCT) is a versatile optical method for cross-sectional and 3D imaging of biological and non-biological objects. Here we are going to present the application of polarization sensitive spectroscopic OCT system (PS-SOCT) for quantitative measurements of materials containing nanoparticles. The PS-SOCT combines the polarization sensitive analysis with time-frequency analysis. In this contribution the benefits of using the combination of timefrequency and polarization sensitive analysis are being expressed. The usefulness of PS-SOCT for nanoparticles evaluation is going to be tested on nanocomposite materials with TiO2 nanoparticles. The OCT measurements results have been compared with SEM examination of the PMMA matrix with nanoparticles. The experiment has proven that by the use of polarization sensitive and spectroscopic OCT the nanoparticles dispersion and size can be evaluated.

RESPONSE OF THE GREEK EARLY WARNING SYSTEM REUTER-STOKES IONIZATION CHAMBERS TO TERRESTRIAL AND COSMIC RADIATION EVALUATED IN COMPARISON WITH SPECTROSCOPIC DATA AND TIME SERIES ANALYSIS.

Science.gov (United States)

Leontaris, F; Clouvas, A; Xanthos, S; Maltezos, A; Potiriadis, C; Kiriakopoulos, E; Guilhot, J

2018-02-01

The Telemetric Early Warning System Network of the Greek Atomic Energy Commission consists mainly of a network of 24 Reuter-Stokes high-pressure ionization chambers (HPIC) for gamma dose rate measurements and covers all Greece. In the present work, the response of the Reuter-Stokes HPIC to terrestrial and cosmic radiation was evaluated in comparison with spectroscopic data obtained by in situ gamma spectrometry measurements with portable hyper pure Germanium detectors (HPGe), near the Reuter-Stokes detectors and time series analysis. For the HPIC detectors, a conversion factor for the measured absorbed dose rate in air (in nGy h-1) to the total ambient dose equivalent rate Ḣ*(10), due to terrestrial and cosmic component, was deduced by the field measurements. Time series analysis of the mean monthly dose rate (measured by the Reuter-Stokes detector in Thessaloniki, northern Greece, from 2001 to 2016) was performed with advanced statistical methods (Fast Fourier Analysis and Zhao Atlas Marks Transform). Fourier analysis reveals several periodicities (periodogram). The periodogram of the absorbed dose rate in air values was compared with the periodogram of the values measured for the same period (2001-16) and in the same location with a NaI (Tl) detector which in principle is not sensitive to cosmic radiation. The obtained results are presented and discussed. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Imaging and spectroscopic observations of the 9 March 2016 Total Solar Eclipse in Palangkaraya

International Nuclear Information System (INIS)

Kholish, Abdul Majid Al; Jihad, Imanul; Andika, Irham Taufik; Puspitaningrum, Evaria; Ainy, Fathin Q.; Ramadhan, Sahlan; Arifyanto, M. Ikbal; Malasan, Hakim L.

2016-01-01

The March 9 th 2016 total solar eclipse observation was carried out at Universitas Palangkaraya, Central Kalimantan. Time-resolved imaging of the Sun has been conducted before, after, and during totality of eclipse while optical spectroscopic observation has been carried out only at the totality. The imaging observation in white light was done to take high resolution images of solar corona. The images were taken with a DSLR camera that is attached to a refractor telescope (d=66 mm, f/5.9). Despite cloudy weather during the eclipse moments, we managed to obtain the images with lower signal-to-noise ratio, including identifiable diamond ring, prominence and coronal structure. The images were processed using standard reduction procedure to increase the signal-to-noise ratio and to enhance the corona. Then, the coronal structure is determined and compared with ultraviolet data from SOHO to analyze the correlation between visual and ultraviolet corona. The spectroscopic observation was conducted using a slit-less spectrograph and a DSLR camera to obtain solar flash spectra. The flash spectra taken during the eclipse show emissions of H 4861 Å, He I 5876 Å, and H 6563 Å. The Fe XIV 5303 Å and Fe X 6374 Å lines are hardly detected due to low signal-to-noise ratio. Spectral reduction and analysis are conducted to derive the emission lines intensity relative to continuum intensity. We use the measured parameters to determine the temperature of solar chromosphere. (paper)

Spectroscopic ellipsometry analysis of GaAs1-xNx layers grown by molecular beam epitaxy

International Nuclear Information System (INIS)

Ben Sedrine, N.; Rihani, J.; Stehle, J.L.; Harmand, J.C.; Chtourou, R.

2008-01-01

In this work, we present the effect of nitrogen incorporation on the dielectric function of GaAsN samples, grown by molecular beam epitaxy (MBE) followed by a rapid thermal annealing (for 90 s at 680 deg. C). The GaAs 1-x N x samples with N content up to 1.5% (x = 0.0%, 0.1%, 0.5%, 1.5%), are investigated using room temperature spectroscopic ellipsometry (SE). The optical transitions in the spectral region around 3 eV are analyzed by fitting analytical critical point line shapes to the second derivative of the dielectric function. It was found that the features associated with E 1 and E 1 + Δ 1 transitions are blue-shifted and become less sharp with increasing nitrogen incorporation, in contrast to the case of E 0 transition energy in GaAs 1-x N x . An increase of the split-off Δ 1 energy with nitrogen content was also obtained, in agreement to results found with MOVPE GaAs 1-x N x grown samples

Optical gradients in a-Si:H thin films detected using real-time spectroscopic ellipsometry with virtual interface analysis

Science.gov (United States)

Junda, Maxwell M.; Karki Gautam, Laxmi; Collins, Robert W.; Podraza, Nikolas J.

2018-04-01

Virtual interface analysis (VIA) is applied to real time spectroscopic ellipsometry measurements taken during the growth of hydrogenated amorphous silicon (a-Si:H) thin films using various hydrogen dilutions of precursor gases and on different substrates during plasma enhanced chemical vapor deposition. A procedure is developed for optimizing VIA model configurations by adjusting sampling depth into the film and the analyzed spectral range such that model fits with the lowest possible error function are achieved. The optimal VIA configurations are found to be different depending on hydrogen dilution, substrate composition, and instantaneous film thickness. A depth profile in the optical properties of the films is then extracted that results from a variation in an optical absorption broadening parameter in a parametric a-Si:H model as a function of film thickness during deposition. Previously identified relationships are used linking this broadening parameter to the overall shape of the optical properties. This parameter is observed to converge after about 2000-3000 Å of accumulated thickness in all layers, implying that similar order in the a-Si:H network can be reached after sufficient thicknesses. In the early stages of growth, however, significant variations in broadening resulting from substrate- and processing-induced order are detected and tracked as a function of bulk layer thickness yielding an optical property depth profile in the final film. The best results are achieved with the simplest film-on-substrate structures while limitations are identified in cases where films have been deposited on more complex substrate structures.

Evaluation of multivariate calibration models transferred between spectroscopic instruments

DEFF Research Database (Denmark)

Eskildsen, Carl Emil Aae; Hansen, Per W.; Skov, Thomas

2016-01-01

In a setting where multiple spectroscopic instruments are used for the same measurements it may be convenient to develop the calibration model on a single instrument and then transfer this model to the other instruments. In the ideal scenario, all instruments provide the same predictions for the ......In a setting where multiple spectroscopic instruments are used for the same measurements it may be convenient to develop the calibration model on a single instrument and then transfer this model to the other instruments. In the ideal scenario, all instruments provide the same predictions...... for the same samples using the transferred model. However, sometimes the success of a model transfer is evaluated by comparing the transferred model predictions with the reference values. This is not optimal, as uncertainties in the reference method will impact the evaluation. This paper proposes a new method...... for calibration model transfer evaluation. The new method is based on comparing predictions from different instruments, rather than comparing predictions and reference values. A total of 75 flour samples were available for the study. All samples were measured on ten near infrared (NIR) instruments from two...

Spectroscopic observations of AG Dra

International Nuclear Information System (INIS)

Chang-Chun, H.

1982-01-01

During summer 1981, spectroscopic observations of AG Dra were performed at the Haute-Provence Observatory using the Marly spectrograph with a dispersion of 80 A mm -1 at the 120 cm telescope and using the Coude spectrograph of the 193 cm telescope with a dispersion of 40 A mm -1 . The actual outlook of the spectrum of AG Dra is very different from what it was in 1966 in the sense that only a few intense absorption lines remain, the heavy emission continuum masking the absorption spectrum, while on the 1966 plate, about 140 absorption lines have been measured. Numerous emission lines have been measured, most of them, present in 1981, could also be detected in 1966. They are due to H, HeI and HeII. (Auth.)

Discovery of Two New Hypervelocity Stars from the LAMOST Spectroscopic Surveys

Energy Technology Data Exchange (ETDEWEB)

Huang, Y.; Liu, X.-W.; Chen, B.-Q. [South-Western Institute for Astronomy Research, Yunnan University, Kunming 650500 (China); Zhang, H.-W.; Wang, C.; Tian, Z.-J. [Department of Astronomy, Peking University, Beijing 100871 (China); Xiang, M.-S.; Li, Y.-B. [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Yuan, H.-B. [Department of Astronomy, Beijing Normal University, Beijing 100875 (China); Wang, B., E-mail: yanghuang@pku.edu.cn, E-mail: x.liu@pku.edu.cn, E-mail: zhanghw@pku.edu.cn [Key Laboratory for the Structure and Evolution of Celestial Objects, Yunnan Observatories, CAS, Kunming 650216 (China)

2017-09-20

We report the discovery of two new unbound hypervelocity stars (HVSs) from the LAMOST spectroscopic surveys. They are, respectively, a B2V-type star of ∼7 M {sub ⊙} with a Galactic rest-frame radial velocity of 502 km s{sup −1} at a Galactocentric radius of ∼21 kpc and a B7V-type star of ∼4 M {sub ⊙} with a Galactic rest-frame radial velocity of 408 km s{sup −1} at a Galactocentric radius of ∼30 kpc. The origins of the two HVSs are not clear given their currently poorly measured proper motions. However, the future data releases of Gaia should provide proper motion measurements accurate enough to solve this problem. The ongoing LAMOST spectroscopic surveys are expected to yield more HVSs to form a statistical sample, providing vital constraints on understanding the nature of HVSs and their ejection mechanisms.

Are LOD and LOQ Reliable Parameters for Sensitivity Evaluation of Spectroscopic Methods?

Science.gov (United States)

Ershadi, Saba; Shayanfar, Ali

2018-03-22

The limit of detection (LOD) and the limit of quantification (LOQ) are common parameters to assess the sensitivity of analytical methods. In this study, the LOD and LOQ of previously reported terbium sensitized analysis methods were calculated by different methods, and the results were compared with sensitivity parameters [lower limit of quantification (LLOQ)] of U.S. Food and Drug Administration guidelines. The details of the calibration curve and standard deviation of blank samples of three different terbium-sensitized luminescence methods for the quantification of mycophenolic acid, enrofloxacin, and silibinin were used for the calculation of LOD and LOQ. A comparison of LOD and LOQ values calculated by various methods and LLOQ shows a considerable difference. The significant difference of the calculated LOD and LOQ with various methods and LLOQ should be considered in the sensitivity evaluation of spectroscopic methods.

Utilization of Solar Dynamics Observatory space weather digital image data for comparative analysis with application to Baryon Oscillation Spectroscopic Survey

Science.gov (United States)

Shekoyan, V.; Dehipawala, S.; Liu, Ernest; Tulsee, Vivek; Armendariz, R.; Tremberger, G.; Holden, T.; Marchese, P.; Cheung, T.

2012-10-01

Digital solar image data is available to users with access to standard, mass-market software. Many scientific projects utilize the Flexible Image Transport System (FITS) format, which requires specialized software typically used in astrophysical research. Data in the FITS format includes photometric and spatial calibration information, which may not be useful to researchers working with self-calibrated, comparative approaches. This project examines the advantages of using mass-market software with readily downloadable image data from the Solar Dynamics Observatory for comparative analysis over with the use of specialized software capable of reading data in the FITS format. Comparative analyses of brightness statistics that describe the solar disk in the study of magnetic energy using algorithms included in mass-market software have been shown to give results similar to analyses using FITS data. The entanglement of magnetic energy associated with solar eruptions, as well as the development of such eruptions, has been characterized successfully using mass-market software. The proposed algorithm would help to establish a publicly accessible, computing network that could assist in exploratory studies of all FITS data. The advances in computer, cell phone and tablet technology could incorporate such an approach readily for the enhancement of high school and first-year college space weather education on a global scale. Application to ground based data such as that contained in the Baryon Oscillation Spectroscopic Survey is discussed.

Usefulness of charge-transfer complexation for the assessment of sympathomimetic drugs: Spectroscopic properties of drug ephedrine hydrochloride complexed with some π-acceptors

Science.gov (United States)

Refat, Moamen S.; Ibrahim, Omar B.; Saad, Hosam A.; Adam, Abdel Majid A.

2014-05-01

Recently, ephedrine (Eph) assessment in food products, pharmaceutical formulations, human fluids of athletes and detection of drug toxicity and abuse, has gained a growing interest. To provide basic data that can be used to assessment of Eph quantitatively based on charge-transfer (CT) complexation, the CT complexes of Eph with 7‧,8,8‧-tetracyanoquinodimethane (TCNQ), dichlorodicyanobenzoquinone (DDQ), 1,3-dinitrobenzene (DNB) or tetrabromothiophene (TBT) were synthesized and spectroscopically investigated. The newly synthesized complexes have been characterized via elemental analysis, IR, Raman, 1H NMR, and UV-visible spectroscopy. The formation constant (KCT), molar extinction coefficient (εCT) and other spectroscopic data have been determined using the Benesi-Hildebrand method and its modifications. The sharp, well-defined Bragg reflections at specific 2θ angles have been identified from the powder X-ray diffraction patterns. Thermal decomposition behavior of these complexes was also studied, and their kinetic thermodynamic parameters were calculated with Coats-Redfern and Horowitz-Metzger equations.

Spectroscopic Classifications of Optical Transients with the Lick Shane 3-m telescope

Science.gov (United States)

Dimitriadis, G.; Foley, R. J.

2018-05-01

We report the following classifications of optical transients from spectroscopic observations with the Kast spectrograph on the Shane 3-m telescope. Targets were supplied by ATLAS, ASAS-SN, and the KEGS K2 SN search.

Spectroscopic link between adsorption site occupation and local surface chemical reactivity

DEFF Research Database (Denmark)

Baraldi, A.; Lizzit, S.; Comelli, G.

2004-01-01

rules, from which adsorption sites are directly determined. Theoretical calculations rationalize the results for transition metal surfaces in terms of the energy shift of the d-band center of mass and this proves that adsorbate-induced SCL shifts provide a spectroscopic measure of local surface...

Spectroscopic effects in 1H and 13C NMR spectra of 4,4'-di-substituted 3,3'-diquinolines sulfides

International Nuclear Information System (INIS)

Pluta, K.

1994-01-01

The 1 H and 13 C NMR spectra of 4,4'-disubstituted sulfides of 3,3'-quinolines have been studied in CDCl 3 solutions. The observed spectroscopic effects have been interpreted in terms of molecule structure and configuration. The factors being responsible for the value of spectroscopic effects have been discussed

Theoretical study of H2/+/ spectroscopic properties. II, III. [2p and 3d excited electronic states

Science.gov (United States)

Beckel, C. L.; Shafi, M.; Peek, J. M.

1973-01-01

Description of the theoretical spectroscopic properties of the 2p pi/sub u/ and 3d sigma/sub g/ excited states of the H2/+/ hydrogen molecular ion. Numerical integration of the Schrodinger equation is used to determine vibration-rotation eigenvalues. Dunham power series expansions are used to determine the equilibrium separation, potential coefficients, and spectroscopic constants. The eigenvalues are used to determine delta-G, Bv, Dv, and Hv.

Pair Identity and Smooth Variation Rules Applicable for the Spectroscopic Parameters of H2O Transitions Involving High-J States

Science.gov (United States)

Ma, Q.; Tipping, R. H.; Lavrentieva, N. N.

2010-01-01

Two basic rules (i.e. the pair identity and the smooth variation) applicable for H2O transitions involving high-J states have been discovered. The origins of these rules are the properties of the energy levels and wavefunctions of H2O states with the quantum number J above certain boundaries. As a result, for lines involving high-J states in individually defined groups, all their spectroscopic parameters (i.e. the transition wavenumber, intensity, pressure-broadened half-width, pressure-induced shift, and temperature exponent) must follow these rules. One can use these rules to screen spectroscopic data provided by databases and to identify possible errors. In addition, by using extrapolation methods within the individual groups, one is able to predict the spectroscopic parameters for lines in this group involving very high-J states. The latter are required in developing high-temperature molecular spectroscopic databases such as HITEMP.

THERMAL AND SPECTROSCOPIC ANALYSES OF CAUSTIC SIDE SOLVENT EXTRACTION SOLVENT CONTACTED WITH 16 MOLAR AND 8 MOLAR NITRIC ACID

International Nuclear Information System (INIS)

Fondeur, F; David Hobbs, D; Samuel Fink, S

2007-01-01

Thermal and spectroscopic analyses were performed on multiple layers formed from contacting Caustic Side Solvent Extraction (CSSX) solvent with 1 M or 3 M nitric acid. A slow chemical reaction occurs (i.e., over several weeks) between the solvent and 1 M or 3 M nitric acid as evidenced by color changes and the detection of nitro groups in the infrared spectrum of the aged samples. Thermal analysis revealed that decomposition of the resulting mixture does not meet the definition of explosive or deflagrating material

Spectroscopic studies of the physical origin of environmental aging effects on doped graphene

International Nuclear Information System (INIS)

Chang, J.-K.; Hsu, C.-C.; Liu, S.-Y.; Wu, C.-I.; Gharib, M.; Yeh, N.-C.

2016-01-01

The environmental aging effect of doped graphene is investigated as a function of the organic doping species, humidity, and the number of graphene layers adjacent to the dopant by studies of the Raman spectroscopy, x-ray and ultraviolet photoelectron spectroscopy, scanning electron microscopy, infrared spectroscopy, and electrical transport measurements. It is found that higher humidity and structural defects induce faster degradation in doped graphene. Detailed analysis of the spectroscopic data suggest that the physical origin of the aging effect is associated with the continuing reaction of H_2O molecules with the hygroscopic organic dopants, which leads to formation of excess chemical bonds, reduction in the doped graphene carrier density, and proliferation of damages from the graphene grain boundaries. These environmental aging effects are further shown to be significantly mitigated by added graphene layers.

Spectroscopic study on the stability of morin in aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Bark, Ki Min [Dept. of Chemical Education and Research Institute of Life Science, Gyeongsang National University, Chinju (Korea, Republic of); Im, Seo Eun; Seo, Jung Ja; Park, Ok Hyun; Park, Hyoung Ryun [Dept. of Chemistry, Chonnam National University, Gwangju (Korea, Republic of); Park, Chul Ho [Dept. of Cosmetic Science, Nambu University, Gwangju (Korea, Republic of)

2015-02-15

Morin (3,2,4,5,7-pentahydroxyflavone) is a flavonol conjugated to a resorcinol moiety at the C-2 position, different from many other flavonoids. The UV–vis spectrum of morin in neat water reveals two major absorption bands with maxima at 265 and 387 nm. The substance is stable in acidic solution and neat water. However, its absorption maximum at 387 nm continuously shifts to longer wavelengths and new peaks appeared at wavelengths of 312 nm with increasing pH of the solution. The shape of the absorption spectrum of morin depends on the storage time at a given pH, indicating the occurrence of other successive chemical reactions. The fluorescence spectroscopic results also prove that new conjugated double bonds are formed in the deaerated basic solution at the initial state and decompose with time. This behavior indicates that morin is very unstable, and therefore its decomposition occurs by a sequence of multistep reactions in basic solution. Probable reaction pathways for the reaction are suggested based on the spectroscopic results.

Building global models for fat and total protein content in raw milk based on historical spectroscopic data in the visible and short-wave near infrared range.

Science.gov (United States)

Melenteva, Anastasiia; Galyanin, Vladislav; Savenkova, Elena; Bogomolov, Andrey

2016-07-15

A large set of fresh cow milk samples collected from many suppliers over a large geographical area in Russia during a year has been analyzed by optical spectroscopy in the range 400-1100 nm in accordance with previously developed scatter-based technique. The global (i.e. resistant to seasonal, genetic, regional and other variations of the milk composition) models for fat and total protein content, which were built using partial least-squares (PLS) regression, exhibit satisfactory prediction performances enabling their practical application in the dairy. The root mean-square errors of prediction (RMSEP) were 0.09 and 0.10 for fat and total protein content, respectively. The issues of raw milk analysis and multivariate modelling based on the historical spectroscopic data have been considered and approaches to the creation of global models and their transfer between the instruments have been proposed. Availability of global models should significantly facilitate the dissemination of optical spectroscopic methods for the laboratory and in-line quantitative milk analysis. Copyright © 2016. Published by Elsevier Ltd.

Spectroscopic observations of V443 Herculis - A symbiotic binary with a low mass white dwarf

Science.gov (United States)

Dobrzycka, Danuta; Kenyon, Scott J.; Mikolajewska, Joanna

1993-01-01

We present an analysis of new and existing photometric and spectroscopic observations of the symbiotic binary V443 Herculis. This binary system consists of a normal M5 giant and a hot compact star. These two objects have comparable luminosities: about 1500 solar for the M5 giant and about 1000 solar for the compact star. We identify three nebular regions in this binary: a small, highly ionized volume surrounding the hot component, a modestly ionized shell close to the red giant photosphere, and a less dense region of intermediate ionization encompassing both binary components. The system parameters for V443 Her suggest the hot component currently declines from a symbiotic nova eruption.

Effects of collisions on linear and non-linear spectroscopic line shapes

International Nuclear Information System (INIS)

Berman, P.R.

1978-01-01

A fundamental physical problem is the determination of atom-atom, atom-molecule and molecule-molecule differential and total scattering cross sections. In this work, a technique for studying atomic and molecular collisions using spectroscopic line shape analysis is discussed. Collisions occurring within an atomic or molecular sample influence the sample's absorptive or emissive properties. Consequently the line shapes associated with the linear or non-linear absorption of external fields by an atomic system reflect the collisional processes occurring in the gas. Explicit line shape expressions are derived characterizing linear or saturated absorption by two-or three-level 'active' atoms which are undergoing collisions with perturber atoms. The line shapes may be broadened, shifted, narrowed, or distorted as a result of collisions which may be 'phase-interrupting' or 'velocity-changing' in nature. Systematic line shape studies can be used to obtain information on both the differential and total active atom-perturber scattering cross sections. (Auth.)

Heterogeneously integrated silicon photonics for the mid-infrared and spectroscopic sensing.

Science.gov (United States)

Chen, Yu; Lin, Hongtao; Hu, Juejun; Li, Mo

2014-07-22

Besides being the foundational material for microelectronics, crystalline silicon has long been used for the production of infrared lenses and mirrors. More recently, silicon has become the key material to achieve large-scale integration of photonic devices for on-chip optical interconnect and signal processing. For optics, silicon has significant advantages: it offers a very high refractive index and is highly transparent in the spectral range from 1.2 to 8 μm. To fully exploit silicon’s superior performance in a remarkably broad range and to enable new optoelectronic functionalities, here we describe a general method to integrate silicon photonic devices on arbitrary foreign substrates. In particular, we apply the technique to integrate silicon microring resonators on mid-infrared compatible substrates for operation in the mid-infrared. These high-performance mid-infrared optical resonators are utilized to demonstrate, for the first time, on-chip cavity-enhanced mid-infrared spectroscopic analysis of organic chemicals with a limit of detection of less than 0.1 ng.

Novel spectroscopic techniques with using soft x-ray

International Nuclear Information System (INIS)

Gejo, Tatsuo

2010-01-01

Recent progress of experimental techniques related to synchrotron radiation makes possible of detail investigation of molecular dynamics after irradiation of soft X-ray. We introduce several novel spectroscopic techniques with using soft X-ray: Symmetry-resolved zero kinetic energy electron spectroscopy, symmetry-resolved metastable photofragment spectroscopy, soft X-ray emission spectroscopy, time-resolved fluorescence spectroscopy, and time-resolved-fluorescence mass-selected-ion coincidence spectroscopy. We also show new techniques performed by other groups at BL27SU in SPring-8. (author)

Detection of the spectroscopic signatures of explosives and their degradation products

Science.gov (United States)

Florian, Vivian; Cabanzo, Andrea; Baez, Bibiana; Correa, Sandra; Irrazabal, Maik; Briano, Julio G.; Castro, Miguel E.; Hernandez-Rivera, Samuel P.

2005-06-01

Detection and removal of antipersonnel and antitank landmines is a great challenge and a worldwide enviromental and humanitarian problem. Sensors tuned on the spectroscopic signature of the chemicals released from mines are a potential solution. Enviromental factors (temperature, relative humidity, rainfall precipitation, wind, sun irradiation, pressure, etc.) as well as soil characteristics (water content, compaction, porosity, chemical composition, particle size distribution, topography, vegetation, etc), have a direct impact on the fate and transport of the chemicals released from landmines. Chemicals such as TNT, DNT and their degradation products, are semi-volatile, and somewhat soluble in water. Also, they may adsorb strongly to soil particles, and are susceptible to degradation by microorganisms, light, or chemical agents. Here we show an experimental procedure to quantify the effect of the above variables on the spectroscopic signature. A number of soil tanks under controlled conditions are used to study the effect of temperature, water content, relative humidity and light radiation.

Helium-plasma heating with a powerful proton beam for spectroscopic applications

International Nuclear Information System (INIS)

Arteev, M.S.; Kuznetsov, A.A.; Sulakshin, S.S.

1986-01-01

In this work the authors consider an ion gun which was especially developed for producing a gas plasma and report on the details of an experiment on (ELLIGIBLE) plasma spectroscopy. The current density of the proton beam was measured in the experiments on the axis of the gas tube with the aid of a collimating current collector with the wave impedance of a 75 omega cable. The ion gun was tested in the excitation of a helium plasma. Extremely pure helium with a pressure P = (0.2-1).10 5 Pa was employed. The proton gun which was developed satifies the requirements of spectroscopic plasma experiments and makes it possible to excite a plasma of inert gases under atmospheric pressure over a length of up to 100 cm, with the plasma having high homogeneity and stability. They obtained first results of spectroscopic measurements of the electron concentration of a helium plasma and the results agree with the theoretical predictions

The double-lined spectroscopic binary Iota Pegasi

Science.gov (United States)

Fekel, F. C.; Tomkin, J.

1983-01-01

Reticon observations of the spectroscopic binary Iota Peg at 6430 A show the secondary star's weak, but well defined lines. Determinations have accordingly been made of the secondary velocity curve as well as that of the primary, together with the orbits and the minimum masses of the two components. The 1.31 + or - 0.02 and 0.81 + or - 0.01 solar mass minimum masses are sufficiently close to the expected actual masses to suggest eclipses, despite the relatively long, 10.2-day period. The spectral type of the secondary is estimated to be G8 V.

REAL-TIME ANALYSIS AND SELECTION BIASES IN THE SUPERNOVA LEGACY SURVEY

International Nuclear Information System (INIS)

Perrett, K.; Conley, A.; Carlberg, R.; Balam, D.; Hook, I. M.; Sullivan, M.; Pritchet, C.; Astier, P.; Balland, C.; Guy, J.; Hardin, D.; Pain, R.; Regnault, N.; Basa, S.; Fouchez, D.; Howell, D. A.

2010-01-01

The Supernova Legacy Survey (SNLS) has produced a high-quality, homogeneous sample of Type Ia supernovae (SNe Ia) out to redshifts greater than z = 1. In its first four years of full operation (to 2007 June), the SNLS discovered more than 3000 transient candidates, 373 of which have been spectroscopically confirmed as SNe Ia. Use of these SNe Ia in precision cosmology critically depends on an analysis of the observational biases incurred in the SNLS survey due to the incomplete sampling of the underlying SN Ia population. This paper describes our real-time supernova detection and analysis procedures, and uses detailed Monte Carlo simulations to examine the effects of Malmquist bias and spectroscopic sampling. Such sampling effects are found to become apparent at z ∼ 0.6, with a significant shift in the average magnitude of the spectroscopically confirmed SN Ia sample toward brighter values for z ∼> 0.75. We describe our approach to correct for these selection biases in our three-year SNLS cosmological analysis (SNLS3) and present a breakdown of the systematic uncertainties involved.

Transient full-field vibration measurement using spectroscopical stereo photogrammetry.

Science.gov (United States)

Yue, Kaiduan; Li, Zhongke; Zhang, Ming; Chen, Shan

2010-12-20

Contrasted with other vibration measurement methods, a novel spectroscopical photogrammetric approach is proposed. Two colored light filters and a CCD color camera are used to achieve the function of two traditional cameras. Then a new calibration method is presented. It focuses on the vibrating object rather than the camera and has the advantage of more accuracy than traditional camera calibration. The test results have shown an accuracy of 0.02 mm.

MOSS spectroscopic camera for imaging time resolved plasma species temperature and flow speed

International Nuclear Information System (INIS)

Michael, Clive; Howard, John

2000-01-01

A MOSS (Modulated Optical Solid-State) spectroscopic camera has been devised to monitor the spatial and temporal variations of temperatures and flow speeds of plasma ion species, the Doppler broadening measurement being made of spectroscopic lines specified. As opposed to a single channel MOSS spectrometer, the camera images light from plasma onto an array of light detectors, being mentioned 2D imaging of plasma ion temperatures and flow speeds. In addition, compared to a conventional grating spectrometer, the MOSS camera shows an excellent light collecting performance which leads to the improvement of signal to noise ratio and of time resolution. The present paper first describes basic items of MOSS spectroscopy, then follows MOSS camera with an emphasis on the optical system of 2D imaging. (author)

MOSS spectroscopic camera for imaging time resolved plasma species temperature and flow speed

Energy Technology Data Exchange (ETDEWEB)

Michael, Clive; Howard, John [Australian National Univ., Plasma Research Laboratory, Canberra (Australia)

2000-03-01

A MOSS (Modulated Optical Solid-State) spectroscopic camera has been devised to monitor the spatial and temporal variations of temperatures and flow speeds of plasma ion species, the Doppler broadening measurement being made of spectroscopic lines specified. As opposed to a single channel MOSS spectrometer, the camera images light from plasma onto an array of light detectors, being mentioned 2D imaging of plasma ion temperatures and flow speeds. In addition, compared to a conventional grating spectrometer, the MOSS camera shows an excellent light collecting performance which leads to the improvement of signal to noise ratio and of time resolution. The present paper first describes basic items of MOSS spectroscopy, then follows MOSS camera with an emphasis on the optical system of 2D imaging. (author)

Optical spectroscopic characteristics of lactate and mitochondrion as new biomarkers in cancer diagnosis: understanding Warburg effect

Science.gov (United States)

Liu, C.-H.; Ni, X. H.; Pu, Yang; Yang, Y. L.; Zhou, F.; Zuzolo, R.; Wang, W. B.; Masilamani, V.; Rizwan, A.; Alfano, R. R.

2012-01-01

Cancer cells display high rates of glycolysis even under normoxia and mostly under hypoxia. Warburg proposed this effect of altered metabolism in cells more than 80 years ago. It is considered as a hallmark of cancer. Optical spectroscopy can be used to explore this effect. Pathophysiological studies indicate that mitochondria of cancer cells are enlarged and increased in number. Warburg observed that cancer cells tend to convert most glucose to lactate regardless of the presence of oxygen. Previous observations show increased lactate in breast cancer lines. The focus of this study is to investigate the relative content changes of lactate and mitochondria in human cancerous and normal breast tissue samples using optical spectroscopic techniques. The optical spectra were obtained from 30 cancerous and 25 normal breast tissue samples and five model components (Tryptophan, fat, collagen, lactate and mitochondrion) using fluorescence, Stokes shift and Raman spectroscopy. The basic biochemical component analysis model (BBCA) and a set of algorithm were used to analyze the spectra. Our analyses of fluorescence spectra showed a 14 percent increase in lactate content and 2.5 times increase in mitochondria number in cancerous breast tissue as compared with normal tissue. Our findings indicate that optical spectroscopic techniques may be used to understand Warburg effect. Lactate and mitochondrion content changes in tumors examined using optical spectroscopy may be used as a prognostic molecular marker in clinic applications.

Synthesis of polyimides from α,αʹ-bis(3-aminophenoxy)-p-xylene: Spectroscopic, single crystal XRD and thermal studies

Science.gov (United States)

Ashraf, Ahmad Raza; Akhter, Zareen; Simon, Leonardo C.; McKee, Vickie; Castel, Charles Dal

2018-05-01

The meta-catenated ether-based diamine monomer α,αʹ-bis(3-aminophenoxy)-p-xylene (3APX) was synthesized from dinitro precursor α,αʹ-bis(3-nitrophenoxy)-p-xylene (3NPX). FTIR, 1H and 13C NMR spectroscopic studies accompanied by elemental analysis were performed for structural elucidations of 3NPX and 3APX. The spatial orientations of 3APX were explored by single crystal X-ray diffraction analysis. Its crystal system was found to be monoclinic, adopting the space group P21/c. The synthesized diamine monomer (3APX) was used for preparation of new series of polyimides by reacting with three different dianhydrides (BTDA, ODPA, 6FDA). The relevant copolyimides were developed via incorporation of 4,4ʹ-methylenedianiline (MDA) in the backbone of afore-synthesized polyimides. The structures of polyimides and copolyimides were verified by FTIR and 1H NMR spectroscopic techniques. Their properties were evaluated by dynamic and isothermal TGA (nitrogen and air atmospheres) and WAXRD studies. Polyimides displayed significantly high thermal stability as their degradation started around 400 °C and it was improved further by execution of copolymerization strategy with MDA. The 5% weight loss temperature (T5) of polyimides under nitrogen atmosphere was in the range of 425-460 °C while for copolyimides it increased to 454-498 °C. Thermal decomposition in air was slower than nitrogen between 400 and 550 °C however it was accelerated above 550 °C. Isothermal TGA disclosed that copolyimides have the ability to endure elevated temperatures for extended period. WAXRD analysis showed the amorphous nature of polyimides and copolyimides.

3D-Mössbauer spectroscopic microscope for mc-Si solar cell evaluation

Energy Technology Data Exchange (ETDEWEB)

Ino, Y., E-mail: y-ino@ob.sist.ac.jp; Soejima, H.; Hayakawa, K.; Yukihira, K.; Tanaka, K.; Fujita, H.; Watanabe, T. [Shizuoka Institute of Science and Technology (Japan); Ogai, K.; Moriguchi, K.; Harada, Y. [APCO. Ltd. (Japan); Yoshida, Y. [Shizuoka Institute of Science and Technology (Japan)

2016-12-15

A 3D-Mössbauer Spectroscopic Microscope is developed to evaluate Fe impurities in multi-crystalline Si solar cells, which combines the Mössbauer spectroscopic microscope with a scanning electron microscope (SEM), an electron beam induced current (EBIC), an electron backscatter diffraction (EBSD), and an electron energy analyzer (HV-CSA). In addition, a new moving-coil-actuator with a liner encoder of 100 nm-resolution is incorporated for the operations with both a constant velocity and a constant acceleration mode successfully with the same precision as that obtained by the conventional transducers. Furthermore, a new multi-capillary X-ray lens is designed to achieve a γ-ray spot size less than 100 μm in diameter. The new microscope provides us to investigate the space correlation between Fe impurities and the lattice defects such as grain boundaries in multi-crystalline Si solar cells.

Massive Young Stellar Objects in the Galactic Center. 1; Spectroscopic Identification from Spitzer/IRS Observations

Science.gov (United States)

An, Deokkeun; Ramirez, Solange V.; Sellgren, Kris; Arendt, Richard G.; Boogert, A. C. Adwin; Robitaille, Thomas P.; Schultheis, Mathias; Cotera, Angela S.; Smith, Howard A.; Stolovy, Susan R.

2011-01-01

We present results from our spectroscopic study, using the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope, designed to identify massive young stellar objects (YSOs) in the Galactic Center (GC). Our sample of 107 YSO candidates was selected based on IRAC colors from the high spatial resolution, high sensitivity Spitzer/IRAC images in the Central Molecular Zone (CMZ), which spans the central approximately 300 pc region of the Milky Way Galaxy. We obtained IRS spectra over 5 micron to 35 micron using both high- and low-resolution IRS modules. We spectroscopically identify massive YSOs by the presence of a 15.4 micron shoulder on the absorption profile of 15 micron CO2 ice, suggestive of CO2 ice mixed with CH30H ice on grains. This 15.4 micron shoulder is clearly observed in 16 sources and possibly observed in an additional 19 sources. We show that 9 massive YSOs also reveal molecular gas-phase absorption from C02, C2H2, and/or HCN, which traces warm and dense gas in YSOs. Our results provide the first spectroscopic census of the massive YSO population in the GC. We fit YSO models to the observed spectral energy distributions and find YSO masses of 8 - 23 solar Mass, which generally agree with the masses derived from observed radio continuum emission. We find that about 50% of photometrically identified YSOs are confirmed with our spectroscopic study. This implies a preliminary star formation rate of approximately 0.07 solar mass/yr at the GC.

Spectroscopic and theoretical investigation of conformational changes of proteins by synthesized pyrimidine derivative and its sensitivity towards FRET application

Science.gov (United States)

Ghosh, Swadesh; Singharoy, Dipti; Bhattacharya, Subhash Chandra

2018-04-01

Interest in synthesizing and characterizing (IR, NMR and HRMS spectroscopic methods) a pyrimidine based Schiff-base ligand, 2-(2-(Anthracen-9-ylmethylene) hydrazinyl)-4,6-dimethyl pyrimidine (ANHP) has been developed for its application to ascertain the conformational change of protein and sensitivity towards fluorescence resonance energy transfer (FRET) process. Location of ANHP in bovine serum albumin (BSA) and human serum albumin (HSA) proteins environment has been determined using different spectroscopic techniques. Weakly fluorescent ANHP have shown greater protein induced fluorescence enhancement (PIFE) in case of HSA than BSA, though in both cases energy transfer efficiency are almost same but difference in binding constant values encourages us to find the location of ANHP within the complex protein environment. From the FRET parameter and α-helicity change, it has been found that ANHP bound with Trp-214 of HSA and surface Trp-134 of BSA. Conformational changes of proteins have been observed more for HSA than BSA in presence of ANHP, which has confirmed the location of ANHP in both the protein environments. Coupled with experimental studies, molecular docking analysis has also been done to explain the locations and distance dependent FRET process of ANHP in both proteins.

X-ray polarimetry with the Polarization Spectroscopic Telescope Array (PolSTAR)

DEFF Research Database (Denmark)

Krawczynski, Henric S.; Stern, Daniel; Harrison, Fiona A.

2016-01-01

This paper describes the Polarization Spectroscopic Telescope Array (PolSTAR), a mission proposed to NASA's 2014 Small Explorer (SMEX) announcement of opportunity. PolSTAR measures the linear polarization of 3-50 keV (requirement; goal: 2.5-70 keV) X-rays probing the behavior of matter,radiation ...

Metabolite ratios in 1H MR spectroscopic imaging of the prostate

NARCIS (Netherlands)

Kobus, T.; Wright, A.J.; Weiland, E.; Heerschap, A.; Scheenen, T.W.J.

2015-01-01

In (1)H MR spectroscopic imaging ((1)H-MRSI) of the prostate the spatial distribution of the signal levels of the metabolites choline, creatine, polyamines, and citrate are assessed. The ratio of choline (plus spermine as the main polyamine) plus creatine over citrate [(Cho+(Spm+)Cr)/Cit] is derived

Molecular structure and spectroscopic characterization of Carbamazepine with experimental techniques and DFT quantum chemical calculations

Science.gov (United States)

Suhasini, M.; Sailatha, E.; Gunasekaran, S.; Ramkumaar, G. R.

2015-04-01

A systematic vibrational spectroscopic assignment and analysis of Carbamazepine has been carried out by using FT-IR, FT-Raman and UV spectral data. The vibrational analysis were aided by electronic structure calculations - ab initio (RHF) and hybrid density functional methods (B3LYP) performed with standard basis set 6-31G(d,p). Molecular equilibrium geometries, electronic energies, natural bond order analysis, harmonic vibrational frequencies and IR intensities have been computed. A detailed interpretation of the vibrational spectra of the molecule has been made on the basis of the calculated Potential Energy Distribution (PED) by VEDA program. UV-visible spectrum of the compound was also recorded and the electronic properties, such as HOMO and LUMO energies and λmax were determined by HF/6-311++G(d,p) Time-Dependent method. The thermodynamic functions of the title molecule were also performed using the RHF and DFT methods. The restricted Hartree-Fock and density functional theory-based nuclear magnetic resonance (NMR) calculation procedure was also performed, and it was used for assigning the 13C and 1H NMR chemical shifts of Carbamazepine.

Electrical and spectroscopic diagnostic of an atmospheric double arc argon plasma jet

International Nuclear Information System (INIS)

Tu, X; Cheron, B G; Yan, J H; Cen, K F

2007-01-01

An atmospheric argon plasma jet generated by an original dc double anode plasma torch has been investigated through its electrical and spectroscopic diagnostics. The arc instabilities and dynamic behavior of the argon plasma are analyzed using classical tools such as the statistical method, fast Fourier transform (FFT) and correlation function. The takeover mode is identified as the fluctuation characteristic of the double arc argon plasma jet in our experiment. The FFT and correlation analysis of electrical signals exhibit the only characteristic frequency of 150 Hz, which originates from the torch power and is independent of any change in the operating parameters. No high frequency fluctuations (1-15 kHz) are observed. This indicates that the nature of fluctuations in an argon plasma jet is induced mainly by the undulation of the tri-phase rectified power supply. It is found that each arc root attachment is diffused rather than located at a fixed position on the anode wall. Moreover, the emission spectroscopic technique is performed to determine the electron temperature and number density of the plasma jet inside and outside the arc chamber. Along the torch axis, the measured electron temperature and number density of the double arc argon plasma drop from 12 300 K and 7.6 x 10 22 m -3 at the divergent part of the first anode nozzle, to 10 500 K and 3.1 x 10 22 m -3 at the torch exit. In addition, the validity criteria of the local thermodynamic equilibrium (LTE) state in the plasma arc are examined. The results show that the measured electron densities are in good agreement with those calculated from the LTE model, which indicates that the double arc argon plasma at atmospheric pressure is close to the LTE state under our experimental conditions

Incorporating spectroscopic on-line monitoring as a method of detection for a Lewis cell setup

Energy Technology Data Exchange (ETDEWEB)

Heller, Forrest D.; Casella, Amanda J.; Lumetta, Gregg J.; Nash, Kenneth L.; Sinkov, Sergey I.; Bryan, Samuel A.

2017-01-01

A Lewis cell was designed and constructed for investigating solvent extraction systems by spectrophotometrically monitoring both the organic and aqueous phases in real time. This new Lewis cell was tested and shown to perform well compared to other previously reported Lewis cell designs. The advantage of the new design is that the spectroscopic measurement allows determination of not only metal ion concentrations, but also information regarding chemical speciation—information not available with previous Lewis cell designs. For convenience, the new Lewis cell design was dubbed COSMOFLEX (COntinuous Spectroscopic MOnitoring of Forrest’s Liquid-liquid EXtraction cell).

Recent Advances and Applications of External Cavity-QCLs towards Hyperspectral Imaging for Standoff Detection and Real-Time Spectroscopic Sensing of Chemicals

Directory of Open Access Journals (Sweden)

Ralf Ostendorf

2016-05-01

Full Text Available External-cavity quantum cascade lasers (EC-QCL are now established as versatile wavelength-tunable light sources for analytical spectroscopy in the mid-infrared (MIR spectral range. We report on the realization of rapid broadband spectral tuning with kHz scan rates by combining a QCL chip with a broad gain spectrum and a resonantly driven micro-opto-electro-mechanical (MOEMS scanner with an integrated diffraction grating in Littrow configuration. The capability for real-time spectroscopic sensing based on MOEMS EC-QCLs is demonstrated by transmission measurements performed on polystyrene reference absorber sheets, as well as on hazardous substances, such as explosives. Furthermore, different applications for the EC-QCL technology in spectroscopic sensing are presented. These include the fields of process analysis with on- or even inline capability and imaging backscattering spectroscopy for contactless identification of solid and liquid contaminations on surfaces. Recent progress in trace detection of explosives and related precursors in relevant environments as well as advances in food quality monitoring by discriminating fresh and mold contaminated peanuts based on their MIR backscattering spectrum is shown.

Fourier transform infrared spectroscopic study of gamma irradiated SiO2 nanoparticles

Science.gov (United States)

Huseynov, Elchin; Garibov, Adil; Mehdiyeva, Ravan; Huseynova, Efsane

2018-03-01

In the present work, nano SiO2 particles are investigated before and after gamma irradiation (25, 50, 75, 100 and 200 kGy) using Fourier transform infrared (FTIR) spectroscopy method for the wavenumber between 400-4000 cm-1. It is found that as a result of spectroscopic analysis, five new peaks have appeared after gamma radiation. Two of new obtained peaks (which are located at 687 cm-1 and 2357 cm-1 of wavenumber) were formed as a result of gamma radiation interaction with Si-O bonds. Another three new peaks (peaks appropriate to 941, 2052 and 2357 cm-1 values of wavenumber) appear as a result of interaction of water with nano SiO2 particles after gamma irradiation. It has been defined as asymmetrical bending vibration, symmetrical bending vibration, symmetrical stretching vibration and asymmetrical stretching vibration of Si-O bonds appropriate to peaks.

Dunham spectroscopic constants for the ground and excited states of H2+

International Nuclear Information System (INIS)

Murai, Tomokazu

1975-01-01

The Dunham spectroscopic constants for 12 of the electronic states of H 2 + are computed theoretically from the adiabatic potentials, which are calculated by the author based on the method presented by Bates et al. in the Born-Oppenheimer approximation. (author)

Macromolecular Competition Titration Method: Accessing Thermodynamics of the Unmodified Macromolecule–Ligand Interactions Through Spectroscopic Titrations of Fluorescent Analogs

Science.gov (United States)

Bujalowski, Wlodzimierz; Jezewska, Maria J.

2011-01-01

Analysis of thermodynamically rigorous binding isotherms provides fundamental information about the energetics of the ligand–macromolecule interactions and often an invaluable insight about the structure of the formed complexes. The Macromolecular Competition Titration (MCT) method enables one to quantitatively obtain interaction parameters of protein–nucleic acid interactions, which may not be available by other methods, particularly for the unmodified long polymer lattices and specific nucleic acid substrates, if the binding is not accompanied by adequate spectroscopic signal changes. The method can be applied using different fluorescent nucleic acids or fluorophores, although the etheno-derivatives of nucleic acid are especially suitable as they are relatively easy to prepare, have significant blue fluorescence, their excitation band lies far from the protein absorption spectrum, and the modification eliminates the possibility of base pairing with other nucleic acids. The MCT method is not limited to the specific size of the reference nucleic acid. Particularly, a simple analysis of the competition titration experiments is described in which the fluorescent, short fragment of nucleic acid, spanning the exact site-size of the protein–nucleic acid complex, and binding with only a 1:1 stoichiometry to the protein, is used as a reference macromolecule. Although the MCT method is predominantly discussed as applied to studying protein–nucleic acid interactions, it can generally be applied to any ligand–macromolecule system by monitoring the association reaction using the spectroscopic signal originating from the reference macromolecule in the presence of the competing macromolecule, whose interaction parameters with the ligand are to be determined. PMID:21195223

Macromolecular competition titration method accessing thermodynamics of the unmodified macromolecule-ligand interactions through spectroscopic titrations of fluorescent analogs.

Science.gov (United States)

Bujalowski, Wlodzimierz; Jezewska, Maria J

2011-01-01

Analysis of thermodynamically rigorous binding isotherms provides fundamental information about the energetics of the ligand-macromolecule interactions and often an invaluable insight about the structure of the formed complexes. The Macromolecular Competition Titration (MCT) method enables one to quantitatively obtain interaction parameters of protein-nucleic acid interactions, which may not be available by other methods, particularly for the unmodified long polymer lattices and specific nucleic acid substrates, if the binding is not accompanied by adequate spectroscopic signal changes. The method can be applied using different fluorescent nucleic acids or fluorophores, although the etheno-derivatives of nucleic acid are especially suitable as they are relatively easy to prepare, have significant blue fluorescence, their excitation band lies far from the protein absorption spectrum, and the modification eliminates the possibility of base pairing with other nucleic acids. The MCT method is not limited to the specific size of the reference nucleic acid. Particularly, a simple analysis of the competition titration experiments is described in which the fluorescent, short fragment of nucleic acid, spanning the exact site-size of the protein-nucleic acid complex, and binding with only a 1:1 stoichiometry to the protein, is used as a reference macromolecule. Although the MCT method is predominantly discussed as applied to studying protein-nucleic acid interactions, it can generally be applied to any ligand-macromolecule system by monitoring the association reaction using the spectroscopic signal originating from the reference macromolecule in the presence of the competing macromolecule, whose interaction parameters with the ligand are to be determined. Copyright © 2011 Elsevier Inc. All rights reserved.

Molecular docking, spectroscopic studies and quantum calculations on nootropic drug.

Science.gov (United States)

Uma Maheswari, J; Muthu, S; Sundius, Tom

2014-04-05

A systematic vibrational spectroscopic assignment and analysis of piracetam [(2-oxo-1-pyrrolidineacetamide)] have been carried out using FT-IR and FT-Raman spectral data. The vibrational analysis was aided by an electronic structure calculation based on the hybrid density functional method B3LYP using a 6-311G++(d,p) basis set. Molecular equilibrium geometries, electronic energies, IR and Raman intensities, and harmonic vibrational frequencies have been computed. The assignments are based on the experimental IR and Raman spectra, and a complete assignment of the observed spectra has been proposed. The UV-visible spectrum of the compound was recorded and the electronic properties, such as HOMO and LUMO energies and the maximum absorption wavelengths λmax were determined by the time-dependent DFT (TD-DFT) method. The geometrical parameters, vibrational frequencies and absorption wavelengths were compared with the experimental data. The complete vibrational assignments are performed on the basis of the potential energy distributions (PED) of the vibrational modes in terms of natural internal coordinates. The simulated FT-IR, FT-Raman, and UV spectra of the title compound have been constructed. Molecular docking studies have been carried out in the active site of piracetam by using Argus Lab. In addition, the potential energy surface, HOMO and LUMO energies, first-order hyperpolarizability and the molecular electrostatic potential have been computed. Copyright © 2014 Elsevier B.V. All rights reserved.

Spectroscopic probes of vibrationally excited molecules at chemically significant energies

Energy Technology Data Exchange (ETDEWEB)

Rizzo, T.R. [Univ. of Rochester, NY (United States)

1993-12-01

This project involves the application of multiple-resonance spectroscopic techniques for investigating energy transfer and dissociation dynamics of highly vibrationally excited molecules. Two major goals of this work are: (1) to provide information on potential energy surfaces of combustion related molecules at chemically significant energies, and (2) to test theoretical modes of unimolecular dissociation rates critically via quantum-state resolved measurements.

Ion-beam spectroscopic studies of the 69As nucleus

International Nuclear Information System (INIS)

Badica, T.; Cojocaru, V.; Olariu, A.; Petre, M.; Popescu, I. V.; Gheboianu, A.

2009-01-01

Excited state of the neutron deficient 69 As nucleus were investigated in the 58 Ni( 14 N,2pn) reaction by ion-beam γ spectroscopic methods (excitation functions, γγ-coincidences, angular distributions and linear polarization gated with neutrons). A new more complete level scheme of 69 As has been proposed with spin-parity values. The structure of the nucleus is discussed in the framework of the interaction boson-fermion model (IBFM). (authors)

Grading of cerebral gilomas: correlation with perfusion MRI, spectroscopic MRI and histopathology

International Nuclear Information System (INIS)

Law, M.; Cha, S.; Knopp, E.A.; Johnson, G.; Litt, A.W.

2002-01-01

Full text: The aim of this study was to determine the correlation between perfusion MRI (pMRI), spectroscopic MRI (sMRI) and histopathologic grading of primary glial neoplasms. Echo-planar pMRI has already been shown to be a robust physiological tool in preoperatively predicting tumor grade and guiding stereotactic biopsy (1). Thirty-four patients with a primary glial neoplasm underwent conventional MR imaging, T2*-weighted echo planar pMRI and sMRI. Four rCBV measurements were obtained from the colour maps of each lesion to determine the maximum rCBV. Spectroscopic MRI utilizing 2D chemical shift imaging at a TE of 135 provided multi-voxel spectroscopic data in sixteen of these patients. The maximum Cho/NAA, Cho/Cr, and minimum NAA/Cr ratios were obtained as well as documenting the presence of lactate and lipids. This was compared with the histopathological grading (including staining with H and E, GFAP, vimentin and MIB1, proliferative index) obtained from volumetric resection or stereotactic biopsy. The maximum rCBV in high grade tumors (n=26) ranged from 1.34 to 5.15, with a mean of 3.00 ± 1.21 (SD), and in the low grade tumors (n=8) ranged from 1.47 to 2.49, with a mean of 1.81 ± 1.21 (SD).This difference was statistically significant (p<0.001; Student t test). Maximum values for Cho/NAA, Cho/Cr and minimum NAA/Cr values were 3.24 ± 3.26, 2.49 ± 1.17 and 1.02 ± 0.34, respectively in the high grade (n = 11), and 1.3 ± 0.39, 1.58 ± 0.45 and 0.89 ± 0.37 respectively in the low-grade tumors (n = 5). A statistically significant difference was found for the Cho/Cr ratio (p<0.05) between the high grade and low grade groups. Relative CBV measurements and spectroscopic metabolic ratios are complementary and correlate with histopathology (2,3). These tools provide powerful physiological and metabolic information for preoperative prediction of tumor grade and will guide pre and post operative planning and management. Copyright (2002) Blackwell Science Pty Ltd

Lock-in amplifier- based rotating- analyzer spectroscopic ellipsometer with micro-controlled angular frequency

Energy Technology Data Exchange (ETDEWEB)

Flores C, J.M.; Nunez O, O.F.; Rodriguez P, G.; Lastras M, A.; Lastras M, L.F. [Instituto de Investigacion en Comunicacion Optica, Universidad Autonoma de San Luis Potosi, Alvaro Obregon 64, 78000 San Luis Potosi (Mexico)

2005-07-01

We report on the development of a full operational rotating analyzer spectroscopic ellipsometer. This instrument employs a phase-sensitive amplifier to process the optical signal as an alternative to Fast Fourier Transform analysis. We describe electronic hardware designed to stabilize the rotation frequency of the analyzer prism as well as to drive the device for the positioning of the polarizer prism azimuth. The ellipsometer allows for dielectric function measurement in the energy range from 1.7-5.5 eV, in both ambient air and Ultra High Vacuum (UHV). UHV measurements can be carried out at a temperature as low as 150 K. To evaluate the ellipsometer performance we present results of the determination of the complex dielectric function of a number of semiconductors, namely, GaSb, GaAs, InGaAs, CdTe and CdHgTe. (Author)

Characterization of plasmonic effects in thin films and metamaterials using spectroscopic ellipsometry

NARCIS (Netherlands)

Oates, T.W.H.; Wormeester, Herbert; Arwin, H.

2011-01-01

In this article, spectroscopic ellipsometry studies of plasmon resonances at metal–dielectric interfaces of thin films are reviewed. We show how ellipsometry provides valuable non-invasive amplitude and phase information from which one can determine the effective dielectric functions, and how these

3D-HST: A WIDE-FIELD GRISM SPECTROSCOPIC SURVEY WITH THE HUBBLE SPACE TELESCOPE

International Nuclear Information System (INIS)

Brammer, Gabriel B.; Van Dokkum, Pieter G.; Skelton, Rosalind E.; Nelson, Erica; Bezanson, Rachel; Leja, Joel; Lundgren, Britt; Franx, Marijn; Fumagalli, Mattia; Patel, Shannon; Labbé, Ivo; Rix, Hans-Walter; Schmidt, Kasper B.; Da Cunha, Elisabete; Kriek, Mariska; Erb, Dawn K.; Fan, Xiaohui; Förster Schreiber, Natascha; Illingworth, Garth D.; Magee, Dan

2012-01-01

We present 3D-HST, a near-infrared spectroscopic Treasury program with the Hubble Space Telescope for studying the physical processes that shape galaxies in the distant universe. 3D-HST provides rest-frame optical spectra for a sample of ∼7000 galaxies at 1 2 ) of the CANDELS Treasury survey area with two orbits of primary WFC3/G141 grism coverage and two to four orbits with the ACS/G800L grism in parallel. In the IR, these exposure times yield a continuum signal-to-noise ratio of ∼5 per resolution element at H 140 ∼ 23.1 and a 5σ emission-line sensitivity of ∼5 × 10 –17 erg s –1 cm –2 for typical objects, improving by a factor of ∼2 for compact sources in images with low sky background levels. The WFC3/G141 spectra provide continuous wavelength coverage from 1.1 to 1.6 μm at a spatial resolution of ∼0.''13, which, combined with their depth, makes them a unique resource for studying galaxy evolution. We present an overview of the preliminary reduction and analysis of the grism observations, including emission-line and redshift measurements from combined fits to the extracted grism spectra and photometry from ancillary multi-wavelength catalogs. The present analysis yields redshift estimates with a precision of σ(z) = 0.0034(1 + z), or σ(v) ≈ 1000 km s –1 . We illustrate how the generalized nature of the survey yields near-infrared spectra of remarkable quality for many different types of objects, including a quasar at z = 4.7, quiescent galaxies at z ∼ 2, and the most distant T-type brown dwarf star known. The combination of the CANDELS and 3D-HST surveys will provide the definitive imaging and spectroscopic data set for studies of the 1 < z < 3.5 universe until the launch of the James Webb Space Telescope.

Spectroscopic evidence of hippocampal abnormalities in neocortical epilepsy

Science.gov (United States)

Mueller, S. G.; Laxer, K. D.; Cashdollar, N.; Lopez, R. C.; Weiner, M. W.

2009-01-01

Lesional neocortical epilepsy (NE) can be associated with hippocampal sclerosis or hippocampal spectroscopic abnormalities without atrophy (dual pathology). In this study, magnetic resonance spectroscopic imaging (MRSI) was used to determine the frequency of hippocampal damage/dysfunction in NE with and without structural lesion. Sixteen patients with NE [seven temporal NE (NE-T), nine extratemporal (NE-ET)] and 16 controls were studied with a 2D MRSI sequence (Repetition time/echo time (TR/TE) = 1800/135 ms) covering both hippocampi. Seven NE patients had MR visible lesions (NE-Les), nine had normal MRI (NE-no). In each hippocampus, 12 voxels were uniformly selected. In controls, mean (± SD) NAA/(Cr + Cho) values for each voxel were calculated and voxels with NAA/(Cr + Cho) ≤ (mean in controls – 2SD in controls) were defined as ‘pathological’ in patients. Eight of 16 NE patients had at least two ‘pathological’ voxel (mean 2.5, range 2–5) in one hippocampus. Four were NE-Les and four NE-no. Three (43%) NE-T patients, had evidence for hippocampal damage/dysfunction and five (56%) had NE-ET. The ipsilateral hippocampus was affected in six of eight NE patients. Evidence for unilateral hippocampal damage/dysfunction was demonstrated in 50% of the NE patients. The type of NE, i.e. NE-Les or NE-no, NE-T or NE-ET, had no influence on the occurrence of hippocampal damage/dysfunction. PMID:16618342

Spectroscopic studies of carbon impurities in PISCES-A

International Nuclear Information System (INIS)

Ra, Y.; Hirooka, Y.; Leung, W.K.; Conn, R.W.; Pospieszczyk, A.

1989-08-01

The graphite used for the limiter of the tokamak reactor produces carbon-containing molecular impurities as a result of the interactions with the edge plasma. The behavior of these molecular impurities has been studied using emission spectroscopy. The present study includes: finding molecular bands and atomic lines in the visible spectral range which can be used for the study of the molecular impurities, studying the breakup processes of the molecular impurities on their way from the source into the plasma, developing a spectroscopic diagnostic method for the absolute measurement of the molecular impurity flux resulting from graphite erosion. For these studies, carbon-containing molecules such as CH 4 , C 2 H 2 , C 2 H 4 , and CO 2 were injected into the tokamak-boundary,like plasma generated by PISCES-A. The spectrograms of these gases were taken. Many useful bands and lines were determined from the spectrograms. The breakup processes of these gases were studied by observing the spatial profiles of the emission of the molecules and their radicals for different plasma conditions. For the absolute measurement of the eroded molecular impurity flux, the photon efficiency of the lines and bands were found by measuring the absolute number of the emitted photons and injected gas molecules. The chemical sputtering yield of graphite by hydrogen plasma was spectroscopically measured using the previously obtained photon efficiencies. It showed good agreement with results obtained by weight loss measurements. 16 refs., 7 figs., 1 tab

Raman spectroscopic analyses of preserved historical specimens of human hair attributed to Robert Stephenson and Sir Isaac Newton.

Science.gov (United States)

Edwards, Howell G M; Hassan, Nik F N; Wilson, Andrew S

2004-10-01

The Raman spectra of two historical specimens of human hair attributed to the engineer Robert Stephenson and scientist Sir Isaac Newton, preserved in private collections are reported. Comparisons are made with the Raman spectra of modern hair specimens and with hair from archaeological excavations. The hair spectra collected with a laser excitation of 785 nm are of a better quality than those collected using 1064 nm. The historical hair specimens are remarkably well-defined spectroscopically in terms of the amide I vibrational mode and the [small nu](SS), ascribed to a predominantly gauche-gauche-gauche CSSC conformation. The contrast with degraded hair specimens recovered from archaeological excavations is striking. The presence of a weak feature near 2590 cm(-1) in the hair samples attributed to a [small nu](SH) vibration could be indicative of a reduction process operative on the CSSC cystine keratotic linkages and a possible origin of this is bacterial biodegradation identified histologically. This study demonstrates the molecular information available from non-destructive Raman spectroscopic analysis from single hair shafts or small bundles of fibres which complements information available from histological and destructive analytical techniques for rare biological specimens subjected to conservation or curation procedures in museums or private collections.

Comparison between infrared and Raman spectroscopic analysis of maturing rabbit cortical bone.

Science.gov (United States)

Turunen, Mikael J; Saarakkala, Simo; Rieppo, Lassi; Helminen, Heikki J; Jurvelin, Jukka S; Isaksson, Hanna

2011-06-01

The molecular composition of the organic and inorganic matrices of bone undergoes alterations during maturation. The aim of this study was to compare Fourier transform infrared (FT-IR) and near-infrared (NIR) Raman microspectroscopy techniques for characterization of the composition of growing and developing bone from young to skeletally mature rabbits. Moreover, the specificity and differences of the techniques for determining bone composition were clarified. The humeri of female New Zealand White rabbits, with age range from young to skeletally mature animals (four age groups, n = 7 per group), were studied. Spectral peak areas, intensities, and ratios related to organic and inorganic matrices of bone were analyzed and compared between the age groups and between FT-IR and Raman microspectroscopic techniques. Specifically, the degree of mineralization, type-B carbonate substitution, crystallinity of hydroxyapatite (HA), mineral content, and collagen maturity were examined. Significant changes during maturation were observed in various compositional parameters with one or both techniques. Overall, the compositional parameters calculated from the Raman spectra correlated with analogous parameters calculated from the IR spectra. Collagen cross-linking (XLR), as determined through peak fitting and directly from the IR spectra, were highly correlated. The mineral/matrix ratio in the Raman spectra was evaluated with multiple different peaks representing the organic matrix. The results showed high correlation with each other. After comparison with the bone mineral density (BMD) values from micro-computed tomography (micro-CT) imaging measurements and crystal size from XRD measurements, it is suggested that Raman microspectroscopy is more sensitive than FT-IR microspectroscopy for the inorganic matrix of the bone. In the literature, similar spectroscopic parameters obtained with FT-IR and NIR Raman microspectroscopic techniques are often compared. According to the present

PHOTOMETRIC, SPECTROSCOPIC, AND ORBITAL PERIOD STUDY OF THREE EARLY-TYPE SEMI-DETACHED SYSTEMS: XZ AQL, UX HER, AND AT PEG

Energy Technology Data Exchange (ETDEWEB)

Zola, S. [Astronomical Observatory, Jagiellonian University, ul. Orla 171, PL-30-244 Krakow (Poland); Baştürk, Ö.; Şenavcı, H. V.; Özavcı, İ.; Yılmaz, M. [Ankara University, Faculty of Science, Department of Astronomy and Space Sciences, Tandoğan, TR-06100, Ankara (Turkey); Liakos, A. [Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, National Observatory of Athens, Penteli, Athens (Greece); Gazeas, K. [Department of Astrophysics, Astronomy and Mechanics, National and Kapodistrian University of Athens, Zografos, Athens (Greece); Nelson, R. H. [1393 Garvin Street, Prince George, BC V2M 3Z1 (Canada); Zakrzewski, B., E-mail: szola@oa.uj.edu.pl [Mt Suhora Observatory, Pedagogical University, ul. Podchorazych 2, PL-30-084 Krakow (Poland)

2016-08-01

In this paper, we present a combined photometric, spectroscopic, and orbital period study of three early-type eclipsing binary systems: XZ Aql, UX Her, and AT Peg. As a result, we have derived the absolute parameters of their components and, on that basis, we discuss their evolutionary states. Furthermore, we compare their parameters with those of other binary systems and with theoretical models. An analysis of all available up-to-date times of minima indicated that all three systems studied here show cyclic orbital changes; their origin is discussed in detail. Finally, we performed a frequency analysis for possible pulsational behavior, and as a result we suggest that XZ Aql hosts a δ Scuti component.

Spectroscopic studies on novel donor-acceptor and low band-gap polymeric semiconductors

International Nuclear Information System (INIS)

Cravino, A.

2002-11-01

Novel low band-gap conjugated polymeric semiconductors as well as conjugated electron donor chains carrying electron acceptor substituents were electrochemically prepared and investigated by means of different spectroscopic techniques. Using in situ FTIR and ESR spectroelectrochemistry, the spectroscopic features of injected positive charges are found to be different as opposed to the negative charge carriers on the same conjugated polymer. These results, for which the theoretical models so far developed do not account, demonstrate the different structure and delocalization of charge carriers with opposite signs. In addition, vibrational spectroscopy results proof the enhanced 'quinoid' character of low band-gap conjugated chains. Excited state spectroscopy was applied to study photoexcitations in conjugated polymers carrying tetracyanoanthraquinone type or fullerene moieties. This novel class of materials, hereafter called double-cable polymers, was found promising as alternative to the conjugated polymer:fullerene mixtures currently used for the preparation of 'bulk-heterojunction' polymeric solar cells. (author)

RADIAL VELOCITIES OF GALACTIC O-TYPE STARS. II. SINGLE-LINED SPECTROSCOPIC BINARIES

International Nuclear Information System (INIS)

Williams, S. J.; Gies, D. R.; Hillwig, T. C.; McSwain, M. V.; Huang, W.

2013-01-01

We report on new radial velocity measurements of massive stars that are either suspected binaries or lacking prior observations. This is part of a survey to identify and characterize spectroscopic binaries among O-type stars with the goal of comparing the binary fraction of field and runaway stars with those in clusters and associations. We present orbits for HDE 308813, HD 152147, HD 164536, BD–16°4826, and HDE 229232, Galactic O-type stars exhibiting single-lined spectroscopic variation. By fitting model spectra to our observed spectra, we obtain estimates for effective temperature, surface gravity, and rotational velocity. We compute orbital periods and velocity semiamplitudes for each system and note the lack of photometric variation for any system. These binaries probably appear single-lined because the companions are faint and because their orbital Doppler shifts are small compared to the width of the rotationally broadened lines of the primary.

Integrated Analysis of the Wood Oil from Xanthocyparis vietnamensis Farjon & Hiep. by Chromatographic and Spectroscopic Techniques.

Science.gov (United States)

Bazzali, Ophélie; Thai, Tran Huy; Hoi, Tran Minh; Khang, Nguyen Sinh; Hien, Nguyen Thi; Casanova, Joseph; Bighelli, Ange; Tomi, Félix

2016-06-27

In order to get better knowledge about the volatiles produced by Xanthocyparis vietnamensis, a species recently discovered in Vietnam, its wood oil has been analyzed by a combination of chromatographic (GC, CC) and spectroscopic (GC-MS, (13)C-NMR) techniques. Forty components that accounted for 87.9% of the oil composition have been identified. The composition is dominated by nootkatene (20.7%), 11,12,13-tri-nor-eremophil-1(10)-en-7-one (17.2%), γ-eudesmol (5.1%), nootkatone (4.7%), valencene (3.5%) and 13-nor-eremophil-1(10)-en-11-one (2.6%). The structure of two new compounds-10-epi-nor-γ-eudesmen-11-one and 12-hydroxy-isodihydroagarofuran-has been elucidated, while 11,12,13-tri-nor-eremophil-1(10)-en-7-ol is reported as a natural product for the first time. The composition of X. vietnamensis wood oil varied drastically from those of leaf oils, dominated by hedycaryol (34.4%), phyllocladene (37.8%) or by pimara-6(14)-15-diene (19.4%).

Integrated Analysis of the Wood Oil from Xanthocyparis vietnamensis Farjon & Hiep. by Chromatographic and Spectroscopic Techniques

Directory of Open Access Journals (Sweden)

Ophélie Bazzali

2016-06-01

Full Text Available In order to get better knowledge about the volatiles produced by Xanthocyparis vietnamensis, a species recently discovered in Vietnam, its wood oil has been analyzed by a combination of chromatographic (GC, CC and spectroscopic (GC-MS, 13C-NMR techniques. Forty components that accounted for 87.9% of the oil composition have been identified. The composition is dominated by nootkatene (20.7%, 11,12,13-tri-nor-eremophil-1(10-en-7-one (17.2%, γ-eudesmol (5.1%, nootkatone (4.7%, valencene (3.5% and 13-nor-eremophil-1(10-en-11-one (2.6%. The structure of two new compounds—10-epi-nor-γ-eudesmen-11-one and 12-hydroxy-isodihydroagarofuran—has been elucidated, while 11,12,13-tri-nor-eremophil-1(10-en-7-ol is reported as a natural product for the first time. The composition of X. vietnamensis wood oil varied drastically from those of leaf oils, dominated by hedycaryol (34.4%, phyllocladene (37.8% or by pimara-6(14-15-diene (19.4%.

CDSD-4000: High-resolution, high-temperature carbon dioxide spectroscopic databank

International Nuclear Information System (INIS)

Tashkun, S.A.; Perevalov, V.I.

2011-01-01

We present a high-resolution, high-temperature version of the Carbon Dioxide Spectroscopic Databank called CDSD-4000. The databank contains the line parameters (positions, intensities, air- and self-broadened half-widths, coefficients of temperature dependence of air- and self-broadened half-widths, and air-broadened pressure shifts) of the four most abundant isotopologues of CO 2 . A reference temperature is 296 K and an intensity cutoff is 10 -27 cm -1 /molecule cm -2 at 4000 K. The databank has 628,324,454 entries, covers the 226-8310 cm -1 spectral range and designed for the temperature range 2500-5000 K. Format of CDSD-4000 is similar to that of HITRAN-2008. The databank has been generated within the framework of the method of effective operators and based on the global fittings of spectroscopic parameters (parameters of the effective Hamiltonians and effective dipole moment operators) to observed data collected from the literature. The databank is useful for studying high-temperature radiative properties of CO 2 , including exoplanets atmospheres, aerothemal modeling for Mars entry missions, high-temperature laboratory spectra, and industrial applications. CDSD-4000 is freely accessible via the Internet site (ftp://ftp.iao.ru/pub/CDSD-4000).

The Large Area Radio Galaxy Evolution Spectroscopic Survey (LARGESS): survey design, data catalogue and GAMA/WiggleZ spectroscopy

Science.gov (United States)

Ching, John H. Y.; Sadler, Elaine M.; Croom, Scott M.; Johnston, Helen M.; Pracy, Michael B.; Couch, Warrick J.; Hopkins, A. M.; Jurek, Russell J.; Pimbblet, K. A.

2017-01-01

We present the Large Area Radio Galaxy Evolution Spectroscopic Survey (LARGESS), a spectroscopic catalogue of radio sources designed to include the full range of radio AGN populations out to redshift z ˜ 0.8. The catalogue covers ˜800 deg2 of sky, and provides optical identifications for 19 179 radio sources from the 1.4 GHz Faint Images of the Radio Sky at Twenty-cm (FIRST) survey down to an optical magnitude limit of Imod point-like objects are included, and no colour cuts are applied. In collaboration with the WiggleZ and Galaxy And Mass Assembly (GAMA) spectroscopic survey teams, we have obtained new spectra for over 5000 objects in the LARGESS sample. Combining these new spectra with data from earlier surveys provides spectroscopic data for 12 329 radio sources in the survey area, of which 10 856 have reliable redshifts. 85 per cent of the LARGESS spectroscopic sample are radio AGN (median redshift z = 0.44), and 15 per cent are nearby star-forming galaxies (median z = 0.08). Low-excitation radio galaxies (LERGs) comprise the majority (83 per cent) of LARGESS radio AGN at z < 0.8, with 12 per cent being high-excitation radio galaxies (HERGs) and 5 per cent radio-loud QSOs. Unlike the more homogeneous LERG and QSO sub-populations, HERGs are a heterogeneous class of objects with relatively blue optical colours and a wide dispersion in mid-infrared colours. This is consistent with a picture in which most HERGs are hosted by galaxies with recent or ongoing star formation as well as a classical accretion disc.

Spectroscopic characterization of the ethyl radical-water complex.

Science.gov (United States)

Lin, Chen; Finney, Brian A; Laufer, Allan H; Anglada, Josep M; Francisco, Joseph S

2016-10-14

An ab initio investigation has been employed to determine the structural and spectroscopic parameters, such as rotational constants, vibrational frequencies, vertical excitation energies, and the stability of the ethyl-water complex. The ethyl-water complex has a binding energy of 1.15 kcal⋅mol -1 . The interaction takes place between the hydrogen of water and the unpaired electron of the radical. This interaction is found to produce a red shift in the OH stretching bands of water of ca. 84 cm -1 , and a shift of all UV absorption bands to higher energies.

Dual-probe spectroscopic fingerprints of defects in graphene

DEFF Research Database (Denmark)

Settnes, Mikkel; Power, Stephen; Petersen, Dirch Hjorth

2014-01-01

(e.g., an extended graphene sheet). Applying this method, we study the transport anisotropies in pristine graphene sheets, and analyze the spectroscopic fingerprints arising from quantum interference around single-site defects, such as vacancies and adatoms. Furthermore, we demonstrate that the dual......-probe setup is a useful tool for characterizing the electronic transport properties of extended defects or designed nanostructures. In particular, we show that nanoscale perforations, or antidots, in a graphene sheet display Fano-type resonances with a strong dependence on the edge geometry of the perforation....

The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey

Energy Technology Data Exchange (ETDEWEB)

Ahn, Christopher P.; Alexandroff, Rachael; Allende Prieto, Carlos; Anderson, Scott F.; Anderton, Timothy; Andrews, Brett H.; Aubourg, Éric; Bailey, Stephen; Balbinot, Eduardo; Barnes, Rory; Bautista, Julian; Beers, Timothy C.; Beifiori, Alessandra; Berlind, Andreas A.; Bhardwaj, Vaishali; Bizyaev, Dmitry; Blake, Cullen H.; Blanton, Michael R.; Blomqvist, Michael; Bochanski, John J.; Bolton, Adam S.; Borde, Arnaud; Bovy, Jo; Brandt, W. N.; Brinkmann, J.; Brown, Peter J.; Brownstein, Joel R.; Bundy, Kevin; Busca, N. G.; Carithers, William; Carnero, Aurelio R.; Carr, Michael A.; Casetti-Dinescu, Dana I.; Chen, Yanmei; Chiappini, Cristina; Comparat, Johan; Connolly, Natalia; Crepp, Justin R.; Cristiani, Stefano; Croft, Rupert A. C.; Cuesta, Antonio J.; da Costa, Luiz N.; Davenport, James R. A.; Dawson, Kyle S.; de Putter, Roland; De Lee, Nathan; Delubac, Timothée; Dhital, Saurav; Ealet, Anne; Ebelke, Garrett L.; Edmondson, Edward M.; Eisenstein, Daniel J.; Escoffier, S.; Esposito, Massimiliano; Evans, Michael L.; Fan, Xiaohui; Femenía Castellá, Bruno; Fernández Alvar, Emma; Ferreira, Leticia D.; Filiz Ak, N.; Finley, Hayley; Fleming, Scott W.; Font-Ribera, Andreu; Frinchaboy, Peter M.; García-Hernández, D. A.; Pérez, A. E. García; Ge, Jian; Génova-Santos, R.; Gillespie, Bruce A.; Girardi, Léo; González Hernández, Jonay I.; Grebel, Eva K.; Gunn, James E.; Guo, Hong; Haggard, Daryl; Hamilton, Jean-Christophe; Harris, David W.; Hawley, Suzanne L.; Hearty, Frederick R.; Ho, Shirley; Hogg, David W.; Holtzman, Jon A.; Honscheid, Klaus; Huehnerhoff, J.; Ivans, Inese I.; Ivezić, Željko; Jacobson, Heather R.; Jiang, Linhua; Johansson, Jonas; Johnson, Jennifer A.; Kauffmann, Guinevere; Kirkby, David; Kirkpatrick, Jessica A.; Klaene, Mark A.; Knapp, Gillian R.; Kneib, Jean-Paul; Le Goff, Jean-Marc; Leauthaud, Alexie; Lee, Khee-Gan; Lee, Young Sun; Long, Daniel C.; Loomis, Craig P.; Lucatello, Sara; Lundgren, Britt; Lupton, Robert H.; Ma, Bo; Ma, Zhibo; MacDonald, Nicholas; Mack, Claude E.; Mahadevan, Suvrath; Maia, Marcio A. G.; Majewski, Steven R.; Makler, Martin; Malanushenko, Elena; Malanushenko, Viktor; Manchado, A.; Mandelbaum, Rachel; Manera, Marc; Maraston, Claudia; Margala, Daniel; Martell, Sarah L.; McBride, Cameron K.; McGreer, Ian D.; McMahon, Richard G.; Ménard, Brice; Meszaros, Sz.; Miralda-Escudé, Jordi; Montero-Dorta, Antonio D.; Montesano, Francesco; Morrison, Heather L.; Muna, Demitri; Munn, Jeffrey A.; Murayama, Hitoshi; Myers, Adam D.; Neto, A. F.; Nguyen, Duy Cuong; Nichol, Robert C.; Nidever, David L.; Noterdaeme, Pasquier; Nuza, Sebastián E.; Ogando, Ricardo L. C.; Olmstead, Matthew D.; Oravetz, Daniel J.; Owen, Russell; Padmanabhan, Nikhil; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John K.; Parihar, Prachi; Pâris, Isabelle; Pattarakijwanich, Petchara; Pepper, Joshua; Percival, Will J.; Pérez-Fournon, Ismael; Pérez-Ràfols, Ignasi; Petitjean, Patrick; Pforr, Janine; Pieri, Matthew M.; Pinsonneault, Marc H.; Porto de Mello, G. F.; Prada, Francisco; Price-Whelan, Adrian M.; Raddick, M. Jordan; Rebolo, Rafael; Rich, James; Richards, Gordon T.; Robin, Annie C.; Rocha-Pinto, Helio J.; Rockosi, Constance M.; Roe, Natalie A.; Ross, Ashley J.; Ross, Nicholas P.; Rossi, Graziano; Rubiño-Martin, J. A.; Samushia, Lado; Sanchez Almeida, J.; Sánchez, Ariel G.; Santiago, Basílio; Sayres, Conor; Schlegel, David J.; Schlesinger, Katharine J.; Schmidt, Sarah J.; Schneider, Donald P.; Schultheis, Mathias; Schwope, Axel D.; Scóccola, C. G.; Seljak, Uros; Sheldon, Erin; Shen, Yue; Shu, Yiping; Simmerer, Jennifer; Simmons, Audrey E.; Skibba, Ramin A.; Skrutskie, M. F.; Slosar, A.; Sobreira, Flavia; Sobeck, Jennifer S.; Stassun, Keivan G.; Steele, Oliver; Steinmetz, Matthias; Strauss, Michael A.; Streblyanska, Alina; Suzuki, Nao; Swanson, Molly E. C.; Tal, Tomer; Thakar, Aniruddha R.; Thomas, Daniel; Thompson, Benjamin A.; Tinker, Jeremy L.; Tojeiro, Rita; Tremonti, Christy A.; Vargas Magaña, M.; Verde, Licia; Viel, Matteo; Vikas, Shailendra K.; Vogt, Nicole P.; Wake, David A.; Wang, Ji; Weaver, Benjamin A.; Weinberg, David H.; Weiner, Benjamin J.; West, Andrew A.; White, Martin; Wilson, John C.; Wisniewski, John P.; Wood-Vasey, W. M.; Yanny, Brian; Yèche, Christophe; York, Donald G.; Zamora, O.; Zasowski, Gail; Zehavi, Idit; Zhao, Gong-Bo; Zheng, Zheng; Zhu, Guangtun; Zinn, Joel C.

2012-11-19

The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar spectra, along with the data presented in previous data releases. These spectra were obtained with the new BOSS spectrograph and were taken between 2009 December and 2011 July. In addition, the stellar parameters pipeline, which determines radial velocities, surface temperatures, surface gravities, and metallicities of stars, has been updated and refined with improvements in temperature estimates for stars with T_eff<5000 K and in metallicity estimates for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars presented in DR8, including stars from SDSS-I and II, as well as those observed as part of the SDSS-III Sloan Extension for Galactic Understanding and Exploration-2 (SEGUE-2). The astrometry error introduced in the DR8 imaging catalogs has been corrected in the DR9 data products. The next data release for SDSS-III will be in Summer 2013, which will present the first data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) along with another year of data from BOSS, followed by the final SDSS-III data release in December 2014.