Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "spectroscopy" wg kryterium: Temat


Tytuł:
Modulation index optimization for wavelength modulation spectroscopy
Autorzy:
Mohammadi, M. J.
Khorsandi, A.
Ghavami, S. S.
Powiązania:
https://bibliotekanauki.pl/articles/949416.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
wavelength modulation spectroscopy
NIR laser spectroscopy
molecular spectroscopy
Opis:
In this work, the second-harmonic component of wavelength modulation spectroscopy is simulated for R(22) CO2 absorption line to investigate the effect of gas temperature and pressure on the modulation index. We found that the optimum value of modulation index, that is 2.2, is not affected by temperature but gas pressure will change the optimized modulation index. Specifically, when the gas pressure decreased to lower pressures of less than 100 mbar, the modulation index is also decreased and tended exponentially to about two. Accordingly, the optimum value of modulation index is recalculated for a range of CO2 gas pressures to establish a nearly zero pressure deviation in the spectroscopy of very low pressure samples.
Źródło:
Optica Applicata; 2016, 46, 4; 639-650
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Mössbauer spectrometer MsAa-4
Autorzy:
Górnicki, R.
Ruebenbauer, K.
Powiązania:
https://bibliotekanauki.pl/articles/147400.pdf
Data publikacji:
2013
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
gamma-ray spectroscopy
Mössbauer spectroscopy
spectrometers
Opis:
A description of the Mossbauer spectrometer MsAa-4 is given. The spectrometer has a modular design and it could be used as the gamma-ray spectrometer as well. It has almost entirely digital design to assure stability and repeatability. It is powered via the rechargeable battery to make it immune to the power failures. All settings are performed remotely over the Ethernet link used also to transfer data and spectrometer functions. External CAN bus could be used to attach auxiliary equipment. The status of the external equipment could be used to control spectrometer functions. Internal digital oscilloscope monitors vital functions of the spectrometer over the Ethernet link. Driving software operates under Microsoft Windows registered trademark systems and it is fully compatible with the Mosgraf-2009 data processing suite.
Źródło:
Nukleonika; 2013, 58, 1; 17-21
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Acoustical Spectroscopy of Carbohydrate Aqueous Solutions: Saccharides; Alkyl Glycosides; Cyclodextrins. Part I. Conformer Variations
Autorzy:
Kaatze, U.
Powiązania:
https://bibliotekanauki.pl/articles/177869.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
acoustical spectroscopy
non-equilibrium spectroscopy
carbohydrate solutions
Opis:
Acoustical attenuation spectra in the frequency range 12 kHz – 2 GHz and nonequilibrium time domain measurements are briefly reviewed for aqueous solutions of various mono- and disaccharides as well as alkyl glycosides. Several relaxation regimes emerge with relaxation times between 10^-11 s and 10^3 s. In this paper relaxation terms reflecting conformational changes are discussed, particularly mutarotation (10^3 s), chair-chair ring inversion (1 ąs), two modes of pseudorotation (100 ns, 10 ns), disaccharide ring isomerisation (10 ns), and exocyclic side group rotation (1 ns).
Źródło:
Archives of Acoustics; 2010, 35, 4; 715-738
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of low doses of gamma rays on the stability of normal and diabetic erythrocytes
Autorzy:
Kaczmarska, Magdalena
Kopyściańska, Zofia
Fornal, Maria
Grodzicki, Tomasz
Matlak, Krzysztof
Korecki, Józef
Burda, Květoslava
Powiązania:
https://bibliotekanauki.pl/articles/1039830.pdf
Data publikacji:
2011
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
γ rays
diabetes
absorption spectroscopy
Mössbauer spectroscopy
hemoglobin
erythrocytes
hemolysis
Opis:
We studied the influence of low doses of γ radiation (from 0.04 to 1.8 mGy) on the stability of human red blood cells (RBC) from healthy donors and diabetic patients using absorption spectroscopy. Because of the alteration of many enzymatic pathways in diabetic RBCs resulting in strong modification of the lipid and protein membrane components one could expect that the ionizing γ-radiation should influence the stability of the healthy and diabetic cells in a different way. Indeed, distinct discontinuities and monotonic changes of hemolysis detected in the healthy and diabetic RBCs suggest that various enzymatic and chemical processes are activated in these membranes by γ radiation. Mössbauer measurements showed that only the highest applied dose of γ radiation caused modification of hemoglobin in both types of RBCs.
Źródło:
Acta Biochimica Polonica; 2011, 58, 4; 489-496
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Overview of the application of laser - based techniques in plasma - wall interaction research program at IFPiLM
Autorzy:
Kubkowska, M.
Gąsior, P.
Czarnecka, A.
Rosiński, M.
Wołowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/147816.pdf
Data publikacji:
2012
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
plasma-wall interaction
plasma spectroscopy
laser-induced breakdown spectroscopy (LIBS)
Opis:
The purpose of this paper is to give an overview of the progress in the application of the laser-based techniques which has been achieved in the research in the field of plasma-wall interaction (PWI) at the Division of Laser-Produced Plasmas (DLPP), Institute of Plasma Physics and Laser Microfusion (IFPiLM, Warsaw, Poland) since 2005. The evolution of the experimental set-up which started in a simple configuration for the laser ablative co-deposit removal is presented with stress on the milestones which led to subsequent modifications, namely installation of laser induced breakdown spectroscopy (LIBS), fast HR (high resolution) CCDs, pulsed fiber-laser and the common triggering system.
Źródło:
Nukleonika; 2012, 57, 2; 163-166
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Shock heterogeneity and shock history of the recently found ordinary Csátalja chondrite in Hungary
Autorzy:
Kereszturi, A.
Fintor, K
Gyollai, I.
Kereszty, Z.
Szabo, M.
Szalai, Z.
Walter, H.
Powiązania:
https://bibliotekanauki.pl/articles/2059757.pdf
Data publikacji:
2018
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
meteorite
shock impact alteration
ordinary chondrite
infrared spectroscopy
Raman spectroscopy
Opis:
Shock impact-produced mineral alterations in two thin sections of the recently found Csátalja H4 ordinary chondrite meteorite are compared. Peak positions of Raman and infrared spectra of mineral clasts show peaks shifted in wavenumber relative to unshocked reference minerals, and both peak shifts and FWHM values seem to correlate to each other. In the less shocked thin section (Csátalja-1) a more monomineralic and homogeneous composition indicate shock pressures of <15 GPa, while the more shocked Csátalja-2 indicates shock pressure in the 15–17 GPa range. The highest identified infrared peak position shifts range between –48 and +28 cm–1 with peak broadening between 60–84 cm–1 in the case of the feldspars, which, together with sulphide globules, were produced by the shock itself. Feldspar spectra could be detected only by FTIR spectroscopy, but in most cases (above the S3 shock level) the mixed type of the pyroxene-feldspar spectra (both peaks in the same spectra) is in agreement with the shock-produced secondary feldspars. These grains are located around crystalline borders, and probably formed by selective melting, due to shock annealing. In reconstruction of the shock history, an early fragmentation by a lower shock effect and a later increased shock level-related vein and melt pocket formation occurred, with subsequent shock annealing; temporal reconstruction of the shock event is possible only in part. The joint usage of Raman and infrared spectroscopy provided useful insights into the shock-produced changes and their spatial inhomogeneity, while shocked feldspar could be better detected by infrared than by the Raman method.
Źródło:
Geological Quarterly; 2018, 62, 2; 433--446
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Annealing, Stoichiometry, and Surface on Magnetism of (Pr,Dy)FeCoB Microparticles Ensemble
Autorzy:
Kablov, E. N.
Ospennikova, O. G.
Kunitsyna, E. I.
Piskorskii, V. P.
Korolev, D. V.
Morgunov, R. B.
Powiązania:
https://bibliotekanauki.pl/articles/356579.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
rare earth metals
magnets
magnetisation
Mössbauer spectroscopy
X-ray spectroscopy
Opis:
Magnetic properties of powder (Pr,Dy)FeCoB ferrimagnetic alloys and effects of annealing, surface states were analyzed. X-ray photoelectron spectroscopy and Mössbauer spectra of powders indicate the effect of surface states on phase composition and magnetic properties of the studied powder, if particles average size is smaller than 10 μm. Effect of stoichiometry on magnetic anisotropy was found. Thermal stability of anisotropy field was proved by replacement of Fe atoms with Co atoms.
Źródło:
Archives of Metallurgy and Materials; 2017, 62, 3; 1923-1930
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Charakterystyka powierzchni materiałów nanostrukturalnych z użyciem powierzchniowo wzmocnionej spektroskopii ramana
Characterization of nanostructured materials surfaces with surface-enhanced raman spectroscopy
Autorzy:
Chlebda, D. K.
Powiązania:
https://bibliotekanauki.pl/articles/134722.pdf
Data publikacji:
2016
Wydawca:
ADVSEO
Tematy:
surface-enhanced Raman spectroscopy
nanostructured metal
SERS
surface spectroscopy
catalysis
nanomaterials
Opis:
Nowadays, surface-enhanced Raman spectroscopy (SERS) is being considered as a rapid and powerful vibrational spectroscopy technique for chemical analysis of materials. The Very high incensement in the intensities of the Raman signal allows for application of that method for chemical analysis of nanostructured surfaces covered with suitable enhancing substrates. For SERS measurements, the substrate plays an essential role because it provides a localized metal surface plasmon resonance enhancement of analyte molecules. Moreover, the use of SERS has a great potential to overcome the Raman spectroscopy weaknesses connected with intensity problems and, therefore, can be applied to the field of heterogeneous catalysts. This article reviews the application of nanoparticles substrates as a ground for SERS enhancement. The article also focuses on the recent progress in SERS characterization of catalytic materials. Recent developments in the field of catalytic material characterization for selected tested molecules allow for performing valuable and reproducible SERS experiments on working catalysts in the reaction environment.
Źródło:
Technical Issues; 2016, 1; 8-13
2392-3954
Pojawia się w:
Technical Issues
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badanie olejów napędowych metodą dielektrometrii opartą na spektroskopii impedancyjnej
Evaluation of diesel fuels using dielectric spectroscopy
Autorzy:
Macioszek, Ł.
Powiązania:
https://bibliotekanauki.pl/articles/155862.pdf
Data publikacji:
2014
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
dielektrometria
spektroskopia impedancyjna
olej napędowy
dielectric spectroscopy
impedance spectroscopy
diesel fuel
Opis:
W pracy podjęto próbę oceny przydatności dielektrometrii w badaniu właściwości olejów napędowych typu premium. Przy użyciu systemu pomiarowego do spektroskopii impedancyjnej wykonano wstępne badania, na podstawie których wyznaczono względną przenikalność elektryczną badanych próbek. Wyniki badań pozwalają stwierdzić, że przy uwzględnieniu pewnych ograniczeń, dielektrometria oparta o spektroskopię impedancyjną może pozwolić na analizę olejów napędowych.
In the paper an attempt was made to evaluate the diesel fuels using dielectric spectroscopy to verify experimentally that it can be used to characterize these fuels. Five samples of winter premium diesels from different vendors were examined. Impedance of diesel fuels was measured in the frequency range of 0.01 Hz – 5 kHz with the use of EG&G/Princeton Applied Research laboratory system for impedance spectroscopy. Measurement results are presented in the form of Bode plot in Fig. 1. Complex resistivity of the samples was calculated on the basis of measured impedance and is presented on fig. 2. The simplest electrical equivalent circuit of the measuring cell (parallel R-C circuit) was used to calculate the capacitance and thus dielectric constant of diesel fuels (expression 5) from the collected measurements of impedance. Dielectric constant of diesel fuels’ samples is presented in Fig. 3. In the Fig. 1 and 2 one can notice a diversity in the obtained results that depend on the supplier and hence the exact chemical composition of the tested diesel. This diversity is not so noticeable in Fig. 3 what may be very important in cases when dielectric spectroscopy is used to detect some substances that can be harmful for the engine. The tests’ findings show that dielectric spectroscopy can be used to determine some of the properties of diesel fuels. Ability to detect additional substances in diesel would however depend on the difference in values of dielectric constant of the matters.
Źródło:
Pomiary Automatyka Kontrola; 2014, R. 60, nr 11, 11; 942-944
0032-4140
Pojawia się w:
Pomiary Automatyka Kontrola
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Własności spektroskopowe kompleksów utworzonych przez tlenek grafenu i pochodną porfiryny z grupą arylową
Spectroscopic properties of the complexes formed by graphene oxide and derivative of porphyrin with aryl groups
Autorzy:
Rosiak, N.
Bogucki, A.
Świetlik, R.
Lewandowska, K.
Powiązania:
https://bibliotekanauki.pl/articles/134764.pdf
Data publikacji:
2017
Wydawca:
ADVSEO
Tematy:
Graphene Oxide
porphyrin
hybrid system
photovoltaics
UV-Vis spectroscopy
infrared spectroscopy
Opis:
Hybrid systems based on graphene oxide (GO) modified by organic molecules with the properties of donor and acceptor are very popular. The researches made in the last few years show that these structures have a really interesting photoelectrochemical properties. The ability of graphene oxide to effectively capture electrons, e.g. of porphyrins suggests the potential use of such materials in photovoltaics and molecular optoelectronics. This implies that further research of this group of molecular materials is very important from the point of view of their applications in diodes and transistors. The goal of the research was to create new hybrid systems with donor-acceptor properties, consisting of graphite oxide and porphyrin 5,10,15,20-Tetrakis (4-hydroxyphenyl) -21H, 23H-porphine. The resulting hybrid structure has been characterized by spectroscopic investigation in a wide spectral range from ultraviolet to infrared.
Źródło:
Technical Issues; 2017, 2; 16-22
2392-3954
Pojawia się w:
Technical Issues
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies