Informacja

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

Wyszukujesz frazę "optical absorption" wg kryterium: Temat


Tytuł:
Wide-angle infrared plasmonic perfect absorber based on graphene-silica grating
Autorzy:
Chen, Fang
Powiązania:
https://bibliotekanauki.pl/articles/1835755.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
plasmonic resonance
graphene grating
optical absorption
plasmonic absorber
Opis:
In this paper, wide-angle infrared perfect absorption has been demonstrated by using a double-layer graphene strip grating coupled with a silicon dioxide grating. Numerical simulation of the finite-difference time-domain method indicates that the perfect absorption can be achieved due to the effective impedance matching, and all the incident electromagnetic energy is confined in the Al2O3 layer between the silver substrate and the graphene strip grating. Dual-band perfect absorption is achieved with the change of strip width or chemical potential of the bi-layer graphene strip grating. It is found that the spectral position of the absorption peak can be tuned by the chemical potential or the width of the graphene strip, and additionally by the size of the proposed absorber. Moreover, the proposed perfect absorber shows excellent absorption stability for a wide range of the incident angle up to ±65°. The proposed absorber may find potential application in tunable double band perfect absorbers in the mid-infrared range.
Źródło:
Optica Applicata; 2021, 51, 1; 87-95
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Green to blue-green quartz from Rakowice Wielkie (Sudetes, south-western Poland) – a re-examination of prasiolite-related colour varieties of quartz
Autorzy:
Platonov, Alexej N.
Szuszkiewicz, Adam
Powiązania:
https://bibliotekanauki.pl/articles/127558.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Mineralogiczne
Tematy:
prasiolite
green quartz
optical absorption
Rakowice Wielkie
Sudetes
Opis:
The green colour of prasiolite, defined as naturally occurring transparent macrocrystalline α-quartz with primary colouration, results from the optical absorption centred at ∼13,660 cm-1 and attributed to the FeVI2+→FeVI3+ intervalence charge transfer (Platonov et al. 1992). However, optical absorption spectroscopy of blue-green to green quartz from Rakowice Wielkie, Sudetes, south-western Poland, shows that its primary colouration results from the combination of this band and absorptions at ∼18,500 cm-1 and ∼16,250 cm-1. The first is assigned to a hole centre Fe4+s(Fe3+s-e- ) combined with an electron centre Fe2+I6(Fe3+I6+e- ), while the second from AlO4 4- defects. The quartz is blue-green if the 18,500 cm-1 prevails and becomes pale green if the 16,250 cm-1 band predominates. These colours seem to represent intermediate colour varieties between amethyst and prasiolite. We also suggest that spectral features of coloured quartz varieties might be useful indicators of changes in the physical- and chemical characteristics of the mineral-forming fluids.
Źródło:
Mineralogia; 2015, 46, 1/2; 1-12
1899-8291
1899-8526
Pojawia się w:
Mineralogia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical properties of maize seeds
Autorzy:
Hernandez, A.
Cruz, O.
Ivanov, R.
Dominguez, P.
Carballo, C.
Moreno, I.
Powiązania:
https://bibliotekanauki.pl/articles/25661.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
maize
optical absorption coefficient
photoacoustic spectroscopy
absorption coefficient
seed
optical property
raw material
Źródło:
International Agrophysics; 2011, 25, 3
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dosimetric properties of gammaand electron-irradiated commercial window glasses
Autorzy:
Fuochi, P.
Corda, U.
Lavalle, M.
Kovács, A.
Baranyai, M.
Mejri, A.
Farah, K.
Powiązania:
https://bibliotekanauki.pl/articles/146494.pdf
Data publikacji:
2009
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
silicate glass
gamma rays
electron beam
optical absorption
dosimeter
fading behaviour
Opis:
Two different types of window glasses have been investigated as possible routine dosimeters in the range of 1-50 kGy. Glass samples were irradiated with 3.4 MeV and 8.4 MeV electron beams and the results compared with those obtained by 60Co gamma irradiation. Due to the strong optical absorption at wavelengths ess than 310 nm, even at low doses, optical measurements were limited to the range 320-700 nm. In both types of glasses, irradiation induced two absorption bands around 410 and 600 nm the intensities of which are proportional to dose; the 600 nm band being less sensitive to radiation. These bands have been attributed to non bridging oxygen hole centres existing in two different configurations. Because of the rapid fading of the optical absorbance observed at room temperature immediately after irradiation (greater than 15% in two days), the samples underwent a post-irradiation thermal treatment (150 graduate C for 20 min) to improve the stability of absorbance. The fading characteristics of the irradiated and thermally treated glasses, kept in the dark at room temperature, were studied for several weeks. A fast decay, whose intensity depends on the type and energy of the ionizing radiation, was observed for few days after irradiation and thermal treatment, followed by a much slower decay. The results show that this kind of material could be used as routine dosimeters within a certain dose range, as long as proper calibrations are made for each batch of glass and the appropriate precautions are taken when doing calibration and performing routine dosimetry.
Źródło:
Nukleonika; 2009, 54, 1; 39-43
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparative studies of the optical absorption coefficient spectra in the implanted layers in silicon with the use of nondestructive spectroscopic techniques
Autorzy:
Dorywalski, Krzysztof
Chrobak, Łukasz
Maliński, Mirosław
Powiązania:
https://bibliotekanauki.pl/articles/221542.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
silicon
ion implantation
optical absorption coefficient spectra
modulated free carrier absorption
photo thermal radiometry
ellipsometry
nondestructive techniques
Opis:
This work presents results of comparative studies of the optical absorption coefficient spectra of ion implanted layers in silicon. Three nondestructive and noncontact techniques were used for this purpose: spectroscopic ellipsometry (SE), modulated free carriers absorption (MFCA) and the photo thermal radiometry (PTR). Results obtained with the ellipsometric method are the proof of correctness of the results obtained with the MFCA and PTR techniques. These techniques are usually used for investigations of recombination parameters of semiconductors. They are not used for investigations of the optical parameters of semiconductors. Optical absorption coefficient spectra of Fe+ and Ge+ high energy and dose implanted layers in silicon, obtained with the three techniques, are presented and compared.
Źródło:
Metrology and Measurement Systems; 2020, 27, 2; 323-337
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chosen Aspects Of Investigations Of Solar Cells With The Laser Beam Induced Current Technique
Autorzy:
Chrobak, Ł. B.
Madej, W. R.
Maliński, M. A.
Powiązania:
https://bibliotekanauki.pl/articles/220416.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
nondestructive techniques
laser beam induced current
photovoltaics
silicon
solar cells
I-V characteristics
optical absorption coefficient spectra
Opis:
This paper presents maps of spatial distributions of the short circuit current Isc(x,y) and the open circuit voltage Uoc(x,y) of the investigated low cost solar cells. Visible differences in values of these parameters were explained by differences in the serial and shunt resistances determined for different points of solar cells from measurements of I–V characteristics. The spectral dependence of the photo voltage of solar cell is also shown, discussed and interpreted in the model of amorphous and crystal silicon.
Źródło:
Metrology and Measurement Systems; 2015, 22, 2; 241-250
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reduction of optical noise in near-infrared range laser hygrometry
Autorzy:
Stacewicz, Tadeusz
Winkowski, Mateusz
Kuk, Natalia
Powiązania:
https://bibliotekanauki.pl/articles/2204345.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
hygrometer
laser
absorption spectroscopy
optical interference
Opis:
A contactless laser hygrometer based on light absorption by H2O molecules at 1392.5 nm is described. However, measurement results can be affected by optical noise when applied to an atmospheric tunnel or glass cuvette. The noises (occurring in the form of periodic fringes in the recorded spectrum) come from unexpected interference of the light beams reflected from surfaces of the windows or other optical elements. The method of their suppression is described in this article. It is based on wavelength modulation and signal averaging over the fringes period. Also, an experiment confirming the usefulness of this method is described here.
Źródło:
Metrology and Measurement Systems; 2023, 30, 1; 169--181
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamical and Steady State Processes of Probe Absorption-Dispersion in a Four-Level Quantum Dot Nanostructure
Autorzy:
Asadi Amirabadi, E.
Jamshidnejad, M.
Miraboutalebi, S.
Asadpour, S.
Powiązania:
https://bibliotekanauki.pl/articles/1032323.pdf
Data publikacji:
2017-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
quantum dot nanostructure
absorption
dispersion
optical transient processes
Opis:
In this paper, we investigated the transient electron population and the transient behaviour of the dispersion, absorption and refractive property of weak probe light in a four-level InGaN/GaN quantum dot nanostructure. In order to achieve the wave functions and their corresponding energy levels of the mentioned quantum dot nanostructure, the Schrödinger and Poisson equations is solved selfconsistently for carriers (here electron) in quantum dot. Our findings show that the properties of transient processes can be dramatically affected by parameters such as intensity, detuning and relative phase of applied fields. Our proposed scheme provides a realistic model for transient control of refraction index properties in a quantum dot nanostructure. These results may have potential applications in high speed optical switch for quantum information technologies.
Źródło:
Acta Physica Polonica A; 2017, 131, 6; 1460-1465
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Femtosecond photonics for three-dimensional high density optical data storage
Autorzy:
Kawata, Y.
Tsuji, M.
Inami, W.
Powiązania:
https://bibliotekanauki.pl/articles/384323.pdf
Data publikacji:
2009
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
femtosecond pulse laser
two-photon absorption
confocal microscopy
optical memory
Opis:
We have developed a high density optical data storage by using two-photon absorption process. We have developed a multilayered medium in which photosensitive layers and transparent pressure-sensitive adhesives layer were piled up alternately. We also demonstrate the development of compact high power fiber laser as a light source of high density optical data storage system.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2009, 3, 4; 9-11
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Review on Feasible and Reliable Underwater Wireless Optical Communication System for achieving High Data Rate and Longer Transmission Distance
Autorzy:
Joseph, Lenin
Anandan, Sangeetha
Powiązania:
https://bibliotekanauki.pl/articles/2200713.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
UWOC
underwater channel
oceanic medium
optical signals
absorption
scattering
attenuation
turbulence
Opis:
Underwater Wireless Optical Communication (UWOC) offers significant research prospective with major challenges in the design and implementation. UWOC is capable of providing high rate of data transmission across large distances. This paper attempts to focus on the intricacies of practical implementations and open research issues of UWOC systems. Critical advances and progresses made in the field, modelling techniques and link design challenges are summarised. The purpose of this review is to give suggestions towards feasible and reliable UWOC design with improved performance. Finally the major points are summarized so that it will assist the future research in UWOC.
Źródło:
International Journal of Electronics and Telecommunications; 2022, 68, 4; 815--823
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parameterization of light scattering for solving the inverse problem of determining the concentrations of the principal light scattering and absorbing admixtures in shelf waters
Autorzy:
Pelevin, V.N.
Rostovtseva, V.V.
Powiązania:
https://bibliotekanauki.pl/articles/48226.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
bio-optical modelling
backscattering
sea water
shelf water
light absorption
irradiance
Opis:
A method for estimating the water backscattering coefficient was put forward on the basis of experimental data of diffuse attenuation coefficient for downwelling irradiance and irradiance reflectance. Calculations were carried out for open sea waters of different types and the spectral dependencies were found (‘anomalous’ spectra) and explained. On this basis, a new model of light backscattering on particles in the sea is proposed. This model may be useful for modelling remote sensing reflectance spectra in order to solve the inverse problems of estimating the concentration of natural admixtures in shelf waters.
Źródło:
Oceanologia; 2001, 43, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quality of rapeseed bio-fuel waste: optical properties
Autorzy:
Sujak, A.
Muszynski, S.
Kachel-Jakubowska, M.
Powiązania:
https://bibliotekanauki.pl/articles/25073.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
quality
rapeseed biofuel
waste
waste management
optical property
spectroscopy
infrared absorption
colour
Opis:
The objective of the presented work was to examine the optical properties of selected bio-fuel waste. Three independent optical methods: UV-Vis spectroscopy, infrared spectroscopy and chromametric measurements were applied to establish the possible quality control test for the obtained substances. The following by-products were tested: distilled glycerine, technical glycerine and matter organic non glycerine fraction from rapeseed oil bio-fuel production. The results show that analysis of UV-Vis spectra can give rapid information about the purity of distilled glycerine, while no direct information can be obtained concerning the concentration and kind of impurities. Transmission mode is more useful as compared to absorption, concerning the detection abilities of average UV-Vis spectrometers. Infrared spectroscopy can be used as a complementary method for determining impurities/admixtures in samples. Measurements of chroma give the quickest data to compare the colour of biofuel by-products obtained by different producers. The condition is, however, that the products are received through the same or similar chemical processes. The other important factor is application of well defined measuring background. All the discussed analyses are quick, cheap and non-destructive, and can help to compare the quality of products.
Źródło:
International Agrophysics; 2014, 28, 2
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spectral light absorption by yellow substance in the Kattegat-Skagerrak area
Autorzy:
Hojerslev, N.K.
Aas, E.
Powiązania:
https://bibliotekanauki.pl/articles/48244.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
yellow substance
wavelength
spectral slope
coastal water
Kattegat area
absorption coefficient
Scandinavian fjord
Baltic Sea
optical property
Skagerrak area
light absorption
Opis:
More than 1500 water samples were taken from the Kattegat, the Skagerrak and adjacent waters. The value of the absorption coefficient of yellow substance at 310 nm was found to varyf rom 0.06 to 7.4 m−1 in the open coastal waters, with a mean value of 1.3 m−1. The corresponding wavelength-averaged value (250–450 nm) of the semilogarithmic spectral slope of the coefficient ranges from 0.008 to 0.042 nm−1, and the mean value is 0.023 nm−1. Closer to river discharges, as in the fjords, the values of the slope seem to be more constant at around 0.0175±0.0015 nm−1. In this area the slope must then be known in order to compare absorption at different wavelengths or to model the yellow substance absorption.
Źródło:
Oceanologia; 2001, 43, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling of bio-optical parameters of open ocean waters
Autorzy:
Pelevin, V.N.
Rostovtseva, V.V.
Powiązania:
https://bibliotekanauki.pl/articles/48307.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
yellow substance
chlorophyll pigment
pigment
suspended matter
bio-optical modelling
ocean water
light absorption
Opis:
An original method for estimating the concentration of chlorophyll pigments, absorption of yellow substance and absorption of suspended matter without pigments and yellow substance in detritus using spectral diffuse attenuation coefficient for downwelling irradiance and irradiance reflectance data has been applied to sea waters of different types in the open ocean (case 1). Using the effective numerical single parameter classification with the water type optical index m as a parameter over the whole range of the open ocean waters, the calculations have been carried out and the light absorption spectra of sea waters tabulated. These spectra are used to optimize the absorption models and thus to estimate the concentrations of the main admixtures in sea water. The value of m can be determined from direct measurements of the downward irradiance attenuation coefficient at 500 nm or calculated from remote sensing data using the regressions given in the article. The sea water composition can then be readily estimated from the tables given for any open ocean area if that one parameter m characterizing the basin is known.
Źródło:
Oceanologia; 2001, 43, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model of the in vivo spectral absorption of algal pigments. Part 2. Practical applications of the model
Autorzy:
Majchrowski, R.
Wozniak, B.
Dera, J.
Ficek, D.
Kaczmarek, S.
Ostrowska, M.
Koblentz-Mishke, O.I.
Powiązania:
https://bibliotekanauki.pl/articles/48872.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
practical application
bio-optical modelling
depth
algal pigment
in vivo
sea
statistical model
phytoplankton
light absorption
Opis:
The article describes applications and accuracy analyses of a statistical model of light absorption by phytoplankton that accounts for the influence of photo- and chromatic acclimation on its absorption properties. Part 1 of this work (seeWoźniak et al. 2000, this volume) describes the mathematical apparatus of the model. Earlier models by Woźniak & Ostrowska (1990) and by Bricaud et al. (1995, 1998) are analysed for comparison. Empirical verification of these three models shows that the new model provides a much better approximation of phytoplankton absorption properties than do the earlier models. The statistical errors in estimating the mean absorption coefficient apl, for example, are σ+ = 36% for the new model, whereas for the earlier models the figures are σ+ = 43% (Bricaud et al. 1995, 1998) and σ+ = 59% (Woźniak & Ostrowska 1990). Example applications are given of the new model illustrating the variability in phytoplankton absorption properties with depth and trophicity of the sea.
Źródło:
Oceanologia; 2000, 42, 2
0078-3234
Pojawia się w:
Oceanologia
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