Informacja

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

Wyszukujesz frazę "spectroscopy" wg kryterium: Temat


Tytuł:
Vibrational spectroscopy investigation of montmorillonite-chitosane nanocomposite materials
Autorzy:
Paluszkiewicz, C.
Stodolak, E.
Powiązania:
https://bibliotekanauki.pl/articles/283827.pdf
Data publikacji:
2011
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Polskie Towarzystwo Biominerałów
Tematy:
spectroscopy
chitosan
nanocomposite materials
Opis:
Biomaterials basing on natural polysaccharides, i.e. hiauronic acid, alginate, chitosane are an alternative for already applied bioresorbable synthetic materials basing on synthetic polyhydroxy acids. Their main advantages are good accessibility, low cost, easy forming and high biocompatibility. Additionally , they are a perfect matrix for bioactive nanoparticles i.e. hydroxy apatite (HAp), tricalcium phosphate (TCP) and silica (SiO2). The work presents results of research on nanocomposite consisting of chitosane matrix (CS) modified with a nanofiller, which was natural montmorillonite (MMT). Nanocomposite foils were produced by the casting method. In order to induce better biocompatibility, the surface of the CS/MMT composite was neutralized (bath in NaOH solution). The nanocomposite foils were subjected to a bioactivity test by incubation in SBF at 37oC for 7 days. It was observed that the CS/ MMT material surface showed a local supersaturation, which was a result of apatite nucleation. The CS/ MMT nanocomposites were investigated using FT-IR ( Fourier Transform Infrared Spectroscopy) and Fourier Raman Spectroscopy. FTIR measurements o f the samples were carried out on the transmission and reflection modes. The FTIR microscopy spectra were collected using BioRad Excalibur with ATR attachment as well as microscope UMA500 equipped with MCT detector. Spectra were measure at 4 cm -1 resolution in the region from 4 000 cm -1 to 600 cm -1 . FT-Raman spectra were obtained using a FTS 6000 Bio-Rad spectrometer with Ge detector. The samples were excited with a Nd-YAG laser (1064nm). Additional all materials in all steps experiments were observed under Scanning Electron Microscopy (Nova Nano SEM). Vibrational spectroscopy methods (FT Raman and FTIR) can be used for investigation of nanocomposite foils basing on biopolymers. High sensitivity the applied spectroscopy techniques show that in the result of the neutralization of CS/ MMT foil (via incubation in NaOH solution the biopolymer chain breaks. This phenomena is visible by intensity ratio between COC/COH bands. Increase of reactivity of chitosane chain lead to entrapment of PO4+3-, which is the origin of the apatite forms nucleation process. Chemical treatment of the nanocomposite foils, i.e. NaOH washes in fluences their chemical structure and microstructure. Neutralisation of the foils is the first processing stage which precedes the potential use o fCS/ MMT foils in biomedical applications. The materials show a tendency to apatite crystallisation which may support regeneration of damaged bone tissue. The applied spectroscopic methods allowed to observe changes in the whole volume of the sample. Individual ATR measurements taken at various spectral ranges and penetration depths allow to observe subtle changes in the polymer matrix caused by chemical treatment (NaOH and SBF incubation). Results of the investigations indicate that in the CS/ MMT systems new chemical bonds and related to them vibrations appear. Quantity and quality of the interact ions is related to characteristics of the nanoparticle and the presence of forming apatite structures.
Źródło:
Engineering of Biomaterials; 2011, 14, no. 109-111 spec. iss.; 44
1429-7248
Pojawia się w:
Engineering of Biomaterials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of natural gas by Raman spectroscopy and its application for in-situ measurements
Autorzy:
Dąbrowski, K.
Kuczyński, S.
Włodek, T.
Smulski, R.
Barbacki, J.
Powiązania:
https://bibliotekanauki.pl/articles/298619.pdf
Data publikacji:
2018
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
natural gas
Raman spectroscopy
Opis:
Gaseous hydrocarbons and nitrogen mixtures are characterized with an own designed portable Raman system equipped with a high pressure autoclave and fiber-optic probe. Backscattered radiation is collected through a sapphire window with a probe and transferred to the spectrometer. Samples are measured for a set of pressures in the range of 1–150 bar in ambient temperature. Measurement conditions are set to maintain an one-phase system. Spectra are collected in a wide range of wavenumber 350–3500 cm–1. Initial composition of measured samples is measured be means of gas chromatography. Design computer algorithms automatically detects and characterizes Raman bands for given species and their peak areas. The influence of both pressure and concentration of a given element on given band position and area are demonstrated.
Źródło:
AGH Drilling, Oil, Gas; 2018, 35, 1; 125-138
2299-4157
2300-7052
Pojawia się w:
AGH Drilling, Oil, Gas
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phase constitution of an LaFe11.0Co0.8(Si0.4Al0.6)1.2 alloy investigated by Mössbauer spectroscopy
Autorzy:
Gębara, P.
Pawlik, P.
Wysłocki, J. J.
Szwaja, M.
Powiązania:
https://bibliotekanauki.pl/articles/147912.pdf
Data publikacji:
2013
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
magnetocaloric materials
Mössbauer spectroscopy
Opis:
In the present work the phase constitution and magnetic ordering of the magnetocaloric LaFe11.0Co0.8(Si0.4Al0.6)1.2 alloy in the as-cast state and after annealing at 1323 K for 1 h (in case of ribbons) and 49 days (in case of bulk) were studied. For bulk and ribbon samples in as-cast state three crystalline phases were identified: dominant ferromagnetic alfa-Fe, minor ferromagnetic La(Fe,Co)Si and traces of paramagnetic La(Fe,Si)13 phase. Appropriate heat treatment resulted in the evolution of phase constitution of the alloy, where two crystalline phases were developed: the dominant paramagnetic La(Fe,Si)13 phase and a minor fraction of the ferromagnetic alfa-Fe for both bulk and ribbon samples.
Źródło:
Nukleonika; 2013, 58, 1; 113-116
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Technical setup and physical properties Technical setup and physical properties of a gas-liner pinch
Autorzy:
Büscher, S.
Wrubel, T.
Kunze, H.
Powiązania:
https://bibliotekanauki.pl/articles/146803.pdf
Data publikacji:
2000
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
lineshapes
spectroscopy
Z-pinch
Opis:
he present technical status and physical properties of the gas-liner pinch device in Bochum are presented and discussed. This comprises spectroscopic as well as diagnostic achievements. A short review on the measurements performed at this light source will also be given.
Źródło:
Nukleonika; 2000, 45, 3; 167-172
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of X-ray photoelectron spectroscopy (XPS) and a functional near infrared spectroscopy (fNIRS) in medicine
Autorzy:
Szklarczyk, Marek
Powiązania:
https://bibliotekanauki.pl/articles/1891232.pdf
Data publikacji:
2021-12-02
Wydawca:
Gdański Uniwersytet Medyczny
Tematy:
X-ray photoelectron spectroscopy
XPS
functional near infrared spectroscopy
fNIRS
brain activity
Opis:
The development of modern clinical medicine and the truthful medical diagnosis require hard physicochemical data. Furthermore, the social demands for more accurate and collected data, which refer to human health in real conditions and in real time, force the quest for techniques which would be possible to be applied in a broadly understood clinical field. In this article two techniques are described. A high vacuum technique which is an X-ray photoelectron spectroscopy (XPS), and a functional near infrared spectroscopy (fNIRS), which might be applied in vivo condition. For the both techniques, the results pointing their applicability in the clinical and modern biochemical research are described.
Źródło:
European Journal of Translational and Clinical Medicine; 2021, 4, 2; 86-93
2657-3148
2657-3156
Pojawia się w:
European Journal of Translational and Clinical Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Examination of the Properties of Samples from Glass-Epoxy Core Rods for Composite Insulators Subjected to DC High Voltage
Autorzy:
Wieczorek, K.
Jaroszewski, M.
Ranachowski, P.
Ranachowski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/351254.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
DC high voltage
composite insulator
glass-epoxy core
dielectric spectroscopy
Raman spectroscopy
Opis:
This article presents the results of an examination performed on a set of samples of glass-epoxy core rods used in composite insulators with silicone rubber housings. The goal of the examination was to test the aging resistance of the core material when exposed to Direct Current (DC) high voltage. Long term exposure of a glass-epoxy core rod to DC high voltage may lead to the gradual degradation of its mechanical properties due to the ion migrations. Electrolysis of the core material (glass fiber) may cause electrical breakdown of the insulators and consequently lead to a major failure. After being aged for 6000 hours under DC high voltage, the samples were subjected to microscopic analysis. Their chemical composition was also examined using Raman spectroscopy and their dielectric losses and conductance in the broad range of frequencies were tested using dielectric spectroscopy.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 3; 1281-1286
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Loading Effect of Ag Nanoparticles on Photocatalytic Activity of TiO2 Nanorod Arrays Prepared by Hydrothermal Method
Autorzy:
Lee, Kwangmin
Yoo, Daeheung
Zakiyuddin, Ahmad
Powiązania:
https://bibliotekanauki.pl/articles/2049271.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
TiO2 nanorods
Ag nanoparticles
hydrothermal
Electrochemical impedance spectroscopy
UV-Vis spectroscopy
Opis:
Rutile-TiO2 nanorod thin films were formed on Ti disks via alkali treatment in NaOH solutions followed by heat treatment at 700°C. Ag nanoparticles were loaded on nanorods using a photo-reduction method to improve the photocatalytic properties of the prepared specimen. The surface characterization and the photo-electrochemical properties of the Ag-loaded TiO2 nanorods were investigated using a field-emission scanning electron microscope (FE-SEM), X-ray photoelectron spectroscopy (XPS), UV-Vis spectroscopy and electrochemical impedance spectroscopy (EIS). The TiO2 nanorods obtained after the heat treatment were 80 to 180 nm thick and 1 μm long. The thickness of the nanorods increased with the NaOH concentration. The UV-Vis spectra exhibit a shift in the absorption edge of the Ag-loaded TiO2 to the visible light range and further narrowing of the bandgap. The decrease in the size of the capacitive loops in the EIS spectra showed that the Ag loading effectively improved the photocatalytic activity of the TiO2 nanorods.
Źródło:
Archives of Metallurgy and Materials; 2021, 66, 3; 751-754
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ultrasonic spectroscopy of silicon single crystal
Autorzy:
Sedlak, P.
Tofel, P.
Sedlakova, V.
Majzner, J.
Sikula, J.
Hasse, L.
Powiązania:
https://bibliotekanauki.pl/articles/220554.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
non-destructive testing
silicon single crystal
electro-ultrasonic spectroscopy
resonant ultrasonic spectroscopy
Opis:
Specimens of Si single crystals with different crystal orientation [100] and [110] were studied by Electro-Ultrasonic Spectroscopy (EUS) and Resonant Ultrasonic Spectroscopy (RUS). A silicon single crystal is an anisotropic crystal, so its properties are different in different directions in the material relative to the crystal orientation. EUS is based on interaction of two signals: an electric AC signal and an ultrasonic signal, which are working on different frequencies. The ultrasonic wave affects the charge carriers' transport in the structures and the intermodulation electrical signal which is created due to the interaction between the ultrasonic wave and charge carriers, is proportional to the density of structural defects. RUS enables to measure natural frequencies of free elastic vibrations of a simply shaped specimen by scanning a selected frequency range including the appropriate resonances of the measured specimens.
Źródło:
Metrology and Measurement Systems; 2011, 18, 4; 621-630
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of quantum cascade lasers to trace gas detection
Autorzy:
Bielecki, Z.
Stacewicz, T.
Wojtas, J.
Mikołajczyk, J.
Powiązania:
https://bibliotekanauki.pl/articles/201703.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
absorption spectroscopy
biomarkers
sensors
gas sensors
cavity enhanced spectroscopy
photoacoustic spectroscopy
spektroskopia absorpcyjna
biomarkery
czujniki gazu
spektroskopia wzmocniona
spektroskopia fotoakustyczna
Opis:
The potential of Quantum Cascade Laser technology has been recently harnessed in industry, medicine and military to create a range of original infrared gas sensors. These sensors have opened up many new applications due to compact size, excellent sensitivity, robust construction and low power requirements. They rely on infrared absorption spectroscopy to determine identity and quantity of gases. The measurement of these gases has relied on different technologies including multi-pass spectroscopy, photoacoustic spectroscopy, cavity ring down spectroscopy, and their various modifications. In this review paper some technologies are described in terms of its advantages/disadvantages in many application. The results of own works about methane, ammonia, nitric oxide, nitrous oxide, and carbonyl sulfide detection are presented as well.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2015, 63, 2; 515-525
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the Phase Transitions in BNT-BT Lead-Free Ceramics Around Morphotropic Phase Boundary by Mechanical and Dielectric Spectroscopies
Autorzy:
Silva Jr, P. S.
Diaz, J. C. C. A.
Florêncio, O.
Venet, M.
M’Peko, J. C.
Powiązania:
https://bibliotekanauki.pl/articles/353072.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Lead-free piezoelectric ceramics
morphotropic phase boundary
phase transitions
mechanical spectroscopy
dielectric spectroscopy
Opis:
In this work, the syntheses and characterization by mechanical and dielectric spectroscopies of (1-x) Bi0.5Na0.5TiO3-xBaTiO3 (BNT-100xBT), with x = 0.05, 0.06 and 0.07, lead-free piezoelectric ceramics is reported. Ceramic samples of BNT-BT have been prepared by mixed-oxide method and then conventionally sintered. X-ray diffraction patterns of sintered samples, indicated for BNT-7BT the presence of tetragonal (P4mm) complex perovskite structure, whereas for BNT-5BT and BNT-6BT the samples exhibit a mixture of tetragonal (P4mm) and rhombohedral (R3c) crystalline phases, which reveal the presence of a morphotropic phase boundary (MPB) in the BNT-BT system. Measurements of internal friction, Q-1, and the storage modulus, E’, as a function of temperature at various frequencies were carried out in a Dynamic Mechanical Analyzer (DMA), in the temperature range from 0ºC to 600ºC. Dielectric profiles are recorded in the frequency range from 1kHz to 100kHz and the temperature range from room temperature to 475ºC. Mechanical loss spectra obtained for investigated compositions of BNT-BT samples showed different frequency-independent anomalies. Two main anomalies for BNT-5BT and BNT-6BT, observed around 100ºC and 430ºC were associated with the ferroelectric-antiferroelectric and antiferroelectricparaelectric phase transitions, respectively. The results obtained from mechanical loss measurements were supported by dielectric relaxation spectra. For BNT-7BT, outside the MPB, four different frequency-independent processes were observed.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 17-20
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of thermal annealing on structure and oxidation of iron nanowires
Autorzy:
Krajewski, M.
Brzózka, K.
Górka, B.
Lin, W.-S.
Lin, H. -M.
Szumiata, T
Gawroński, M.
Wasik, D.
Powiązania:
https://bibliotekanauki.pl/articles/148838.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
amorphous iron and iron oxides
iron nanowires
Mössbauer spectroscopy
Raman spectroscopy
thermal annealing
Opis:
Raman spectroscopy as well as Mössbauer spectroscopy were applied in order to study the phase composition of iron nanowires and its changes, caused by annealing in a neutral atmosphere at several temperatures ranging from 200°C to 800°C. As-prepared nanowires were manufactured via a simple chemical reduction in an external magnetic fi eld. Both experimental techniques proved formation of the surface layer covered by crystalline iron oxides, with phase composition dependent on the annealing temperature (Ta). At higher Ta, hematite was the dominant phase in the nanowires.
Źródło:
Nukleonika; 2015, 60, 1; 87-91
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Advanced microstructure diagnostics and interface analysis of modern materials by high-resolution analytical transmission electron microscopy
Autorzy:
Neumann, W.
Kirmse, H.
Hausler, I.
Mogilatenko, A.
Zheng, C.
Hetaba, W.
Powiązania:
https://bibliotekanauki.pl/articles/199872.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
electron microscopy
energy dispersive X-ray spectroscopy
electron energy loss spectroscopy
electron holography
Opis:
Transmission electron microscopy (TEM) is a powerful diagnostic tool for the determination of structure/property relationships of materials. A comprehensive analysis of materials requires a combined use of a variety of complementary electron microscopical techniques of imaging, diffraction and spectroscopy at an atomic level of magnitude. The possibilities and limitations of quantitative TEM analysis will be demonstrated for interface studies of the following materials and materials systems: Nickel-based superalloy CMSX-10, (Zn,Cd)O/ZnO/Al2O3, (Al,Ga)N/AlN/Al2O3, GaN/LiAlO2 and FeCo-based nanocrystalline alloys.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2010, 58, 2; 237-253
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mössbauer study of treated Nd2Fe14B
Autorzy:
Budzyński, M.
Constantin, V. C.
Popescu, A.-N. J.
Surowiec, Z.
Tkachenka, T. M.
Yanushkevich, K. I.
Powiązania:
https://bibliotekanauki.pl/articles/146270.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
intermetallics
intergranular corrosion
Mössbauer spectroscopy
Opis:
The Nd2Fe14B cylindrical magnets were treated with water solutions of alkali, acid, and salt. Mössbauer spectroscopy was applied to study the composition and properties of the surface material of the treated magnets. It is shown that the main phase of the permanent Nd2Fe14B magnet partly decomposes. The released α-Nd at the grain boundaries interacts with water and forms neodymium hydroxide matrix, and the released Fe diffuses into it. The presence of Fe-Nd(OH)3 is refl ected in the paramagnet doublet in the Mössbauer spectra of treated neodymium magnets.
Źródło:
Nukleonika; 2015, 60, 1; 7-10
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the influence of a carbon solid on the properties of a helium plasma in a theta pinch discharge
Autorzy:
Freese, W.
Kunze, H.
Powiązania:
https://bibliotekanauki.pl/articles/146807.pdf
Data publikacji:
2000
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
shock wave
spectroscopy
theta pinch
Opis:
A helium plasma produced in a 82 kJ theta pinch discharge has been seeded with carbon ions by a carbon solid rod positioned on the axis. The first shock front of the discharge ablates carbon atoms from the solid surface which are ionized and interact with the plasma. Some shock front properties (namely thickness, compression velocity and its shape) were analyzed with an ICCD-camera system taking 2-dimensional photos of the plasma continuum emitted along the axis with a time duration of 100 ns. While the influence on the shape was not found, the temporal behaviour was drastically changed when the rod was added. The shock front occurs earlier and compresses faster. An explanation remains to be given. Furthermore, the influence of the carbon impurities on the plasma parameters has been investigated by measuring the electron temperature and density by means of plasma spectroscopy comparing these results with those obtained from discharges in helium without rod. We found a decrease in the electron density about 500 ns after the shocked plasma has started to interact with the rod surface. Simultaneously increasing continuum emission and decreasing intensity of the HeII Pa line indicates a regime of recombination. No influence was found on the electron temperature.
Źródło:
Nukleonika; 2000, 45, 3; 173-177
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of corrosion defects in titanium by positron annihilation
Autorzy:
Pietrzak, R.
Szatanik, R.
Powiązania:
https://bibliotekanauki.pl/articles/147338.pdf
Data publikacji:
2015
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
positron annihilation spectroscopy
corrosion defects
Opis:
The positron annihilation method was used to study the formation of defects in titanium samples during their corrosion in the vapor of a 3% HCl solution. In particular, the distribution of defects depending on the distance from the corroding surface and the impact of an external magnetic fi eld on the concentration of vacancies forming during the corrosion of titanium layers close to the surface were determined.
Źródło:
Nukleonika; 2015, 60, No. 4, part 1; 755-758
0029-5922
1508-5791
Pojawia się w:
Nukleonika
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