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1

Infrared luminescence and thermoluminescence of lithium borate glasses doped with Sm3+ ions

Anjaiah J., Laxmikanth C., Veeraiah N., Kistaiah P.

Materials Science Poland

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2015

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Vol. 33, No. 1

144--151

EN

Thermoluminescence (TL) characteristics of X-ray irradiated pure and doped with Sm3>/sup>+ ions Li2O–MO–B sub>2O sub>3 (where MO=Z sub>nO, CaO, CdO) glasses have been studied in the temperature range of 303 to 573 K. All the pure glasses exhibited single TL peaks at 382 K, 424 K and 466 K. When these glasses were doped with Sm3+ ions no additional peaks have been observed but the glow peak temperature of the existing glow peak shifted gradually towards higher temperatures with gain in intensity of TL light output. The area under the glow curve was found to be maximum for Sm3+ doped glasses mixed with cadmium oxide as a modifier. The trap depth parameters associated with the observed TL peaks have been evaluated using Chen’s formulae. The possible use of these glasses in radiation dosimetry has been described. The results clearly showed that samarium doped cadmium borate glass has a potential to be considered as a thermoluminescence dosimeter.

2

Wybrane problemy rozpoznawania obrazów twarzy zarejestrowanych w świetle widzialnym i podczerwieni

Pacan J., Jakubowski J.

Logistyka

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2014

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nr 6

8277--8288

PL

Artykuł dotyczy zagadnienia automatycznego rozpoznawania tożsamości na podstawia obrazów twarzy zarejestrowanych w zakresie światła widzialnego i podczerwieni. Wykorzystywana metoda identyfikacji oparta jest na algorytmie SIFT (ang. Scale Invariant Feature Transform). Łatwość i bezinwazyjność pozyskiwania danych do analizy, jakim jest obraz twarzy badanej osoby, stwarza problemy związane ze zmianami warunków jego akwizycji. W artykule zamieszczono wyniki badań mających na celu ocenę wpływu na proces identyfikacji zmian następujących czynników: natężenia oświetlenia, kierunku padania światła oraz azymutalnego kąta ustawienia urządzenia rejestrującego obraz względem obserwowanego obiektu. Wyniki przeprowadzonych badań wykazują, że zmiany warunków oświetleniowych mają większy wpływ na proces identyfikacji przy analizie obrazów z zakresy światła widzialnego. Wykorzystane w badaniach tradycyjne źródło światła nie wprowadzało znaczących modyfikacji w obrazie z zakresu podczerwieni. Jednak zmiany kąta ustawienia kamery względem twarzy miały negatywny wpływ na proces identyfikacji niezależnie od zakresu spektralnego wykorzystywanych obrazów.

EN

The paper deals with the problem of automatic identification on the basis of face images acquired in visible and infrared spectra. The identification method used in the research is based on the algorithm called SIFT in short (it stands for Scale Invariant Feature Transform). In case of face recognition, acquiring data for the identification process is an easy task and can be done without the cooperation of an examined person or even without their knowledge of being identified. Unfortunately, itcan introduce significant modifications to acquired images because of changing illumination conditions or different positions of the camera in relation to the objectthat is observed. The paper presents the results of the research, which was conducted with the objective of assessing the influence of selected factors, which can modify an acquired image, on the identification process. The results of the research reveal that changes in illumination during image acquisition process have significant influence on the identification process while processing images acquired in visible spectrum. The source of the light used in the research do not introduce visible modifications to infrared images. However, changes in camera position have negative influence on the identification process regardless of the spectrum range of the analyzed images.

3

Influence of MoO3 on the Structure of Lithium Aluminum Phosphate Glasses

Saddeek Y. B., Abo-Naf S. M.

Archives of Acoustics

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2012

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Vol. 37, No. 3

341-347

EN

IR spectroscopy, density and ultrasonic velocity measurements have been carried out for aluminum lithium phosphate glasses with and without MoO3. The observed changes in the FTIR spectra of the glasses were related to the modifier/former role of molybdenum ions. The results revealed that the density increases with increasing MoO3 content, which was attributed to the increase in the compactness and packing of the glass network. The ultrasonic data were analyzed in terms of creation of new bonds of MoO3 attached to phosphate units. The new bonds increased the average crosslink density and the number of network bonds per unit volume along with a strengthening of the different modes of vibrations which in its turn increased the ultrasonic velocity, the rigidity and hence the elastic moduli of the glasses.

4

Silne wiązania wodorowe w kompleksach wybranych kwasów organicznych z tetrametylopirazyną

Bator G., Sobczyk L.

Wiadomości Chemiczne

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2011

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[Z] 65, 9-10

869-885

EN

In the present review our interest is focused on the hydrogen bonded complexes of tetramethylpyrazine (TMP) with strong proton donors, in particular with chloranilic (CLA) or squaric (H2SQ) acid. The x-ray diffraction studies show that, depending on the proton donor, various assemblies with the acid are formed, e.g. the infinite O-H…N hydrogen bonded chains without proton transfer in the case of the complex with CLA. On the other hand with H2SQ the assemblies of [HSQ]2 2–-2TMPźH+ composition are created, in which the ionized HSQ–1 molecules are present in the form of dimers. These dimers are bound with the TMPźH+ cations on its both sides via the +N-H…O– hydrogen bonds. Picric acid forms with TMP the complex of the 2:1 composition with a double protonated TMP molecule. In the case of HI3 acid the interesting units of the (TMPźH+)2źTMP composition are formed, in which two TMPźH+ cations are coordinated with one TMP molecule through the +N-H…N bridges. In the infrared spectra of the TMP complexes, both with CLA and H2SQ, the similar absorption continua are observed. They can be interpreted in terms of an asymmetric potential for the proton motion, with either the double minimum or the single broad minimum potential for the CLA and H2SQ complexes, respectively. An analysis of the neutron scattering spectra concerns the phenomena of the tunneling splitting, quasielastic neutron scattering (QNS) and inelastic (INS) scattering. In the case of tunneling splitting neat TMP does not show any tunneling transitions in the ěeV energy region, because they are overlapped by the elastic scattering band. In the case of the TMPźCLA complex four tunneling transitions are seen corresponding to the four crystallographically nonequivalent CH3 groups in the TMP molecule. In the spectrum of the complex with squaric acid the observed two transitions are ascribed to the two different CH3 groups. The two remaining CH3 group tunneling transitions are overlapped by the elastic scattering. The measurements in various low temperature ranges yield information about the shape of the CH3 group rotational potential. The shape of the potential is also reflected in the spectra of quasielastic scattering. In particular the temperature dependence of the quasielastic band allows us to find the activation energy for the CH3 rotations. Finally the inelastic neutron scattering spectra are analyzed in the energy range of the CH3 torsional modes (below 200 cm–1 = 25 meV). The analysis shows that for the complexes the torsional vibration frequencies are markedly lower than those for neat TMP. In the case of the TMPźCLA complex frequencies found are particularly low. They are close to the frequencies calculated for the TMP+ cation. A general conclusion can be drawn that in the complexes the CH3 groups behave more loosely than in neat TMP.

5

Infrared Matrix Isolation and Theoretical Study of Methylglyoxal

Mucha M., Sałdyka M., Mielke Z.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 5

943-956

EN

Methylglyoxal (MG) was studied by matrix-isolation IR spectroscopy supported by MP2/6-311++G(2d,2p) calculations. The experimental results show that the molecule exists in the trans conformation (Cs symmetry). The trans-MG isomer is estimated to lie 4.96 kcal/mol be low the cis-MG isomer and the rotational barrier is 5.48 kcal/mol on the ground-state path way from trans- to cis-MG. The spectra evidence formation of weak molecular MGźźźN2 complexes when the argon matrix is doped both with MG and N2.

6

Nanosilica Partially Modifiedby Hexamethyldisilazane in Air

Gun'ko V., Voronina O., Voronin E., Zarko V., Pakhlov E., Leboda, Skubiszewska-Zięba J., Janusz W., Chibowski S.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 11

1787-1804

EN

Unmodified and modified nanosilicas containing different content of trimethylsilyl (TMS) groups grafted by interaction with various amounts of hexamethyldisilazane (HMDS) in a reactor contacting with air were studied using infrared spectroscopy, adsorption and potentiometric titration methods. Contribution of narrow gaps between spherical primary silica particles forming aggre gates decreases with in creasing TMS loading (tetaTMS), because of blocking of these gaps by grafted functionalities. Contribution of broader gaps corresponding to mesopores de ends slightly on tetaTMS, and changes in contribution of macropores are rather random. IR spectra of modified samples depict changes in bands of the O-H stretch ingvibrations at 3750 and 3300 cm-1 (reduced with qTMS) and 3680 and 3500 cm-1 (changed nonlinearly with qTMS), since HMDS can interact with silanols and ad sorbed water and af fect the ad sorbed amounts of water. Enhance ment of the hydrophobic properties of the surface reduces the amounts of adsorbed water, and the IR band in tensity at 3300 cm-1 di minishes. The adsorption of poly(vinyl pyrrolidone) on silicas decreases with tetaTMS in consequence of changes in the surface structure and the reduction of adsorption potential. The silylation diminishes the su face charge density and the electrostatic surface poten tial, and the point of zero charge shifts to ward larger pH values with in creasing tetaTMS value.

7

Infrared study of copper(II) complexes with pyridine-3-carboxamide derivatives in chloride media

Borowiak-Resterna A., Olszanowski A.

Ars Separatoria Acta

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2004

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No. 3

105-113

EN

The extraction studies for copper(II) from chloride solutions by mono- and dialkyl derivatives of benzamide and pyridine-3-carboxamide show that the coordination of copper by amide groups is very weak, weaker than by chloride ions. N,N-dialkyl derivative of benzamide does not extract copper from chloride media but N-alkylbenzamide eliminates a small amount of copper (a great deal smaller than pyridine-3-carboxamide derivatives) only from diluted chloride aqueous solutions ([Cl-] < 0.1 M). Infrared studies of copper complexes with mono- and dialkylpyridine-3-carboxamides show that coordination of the ligand molecules to copper(II) ions takes place mainly by the pyridine nitrogen. More stable monoalkylpyridinecarboxamides complexes with CuCl2 are formed probably by intermolecular hydrogen bonds between monomeric molecules of CuCl2L2 complex (L – the amide). However, weak coordination of copper(II) by the amide group may take place.

8

Infrared Matrix Isolation Studies and Ab Initio Calculations of Acetohydroxamic Acid

Sałdyka M., Mielke Z.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 11

1587-1598

EN

The infrared absorption spectra of acetohydroxamic acid (CH3CONHOH) and its deuterated analogue (CH3CONDOD) isolated in argon and nitrogen matrices have been recorded for the first time. The infrared spectra prove that this molecule exists as the keto tautomer with intramolecular hydrogen bond in solid argon and nitrogen. Theoretical studies of the structure and spectral characteristics of the acetohydroxamic acid molecule, carried out on both MP2 and B3LYP levels with the 6-311++G(2d,2p) basis set, are in accordance with the experimental data.

9

Theoretical simulation of infrared spectra of acetylsalicylic acid

Boczar M., Wójcik M. J., Szczeponek K., Jamróz D., Zięba A.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 4

397-402

EN

Theoretical simulation of the v(s) stretching band is presented for acetylsalicylic acid (aspirin) at two temperatures 77 and 300 K. The simulation takes into account adiabatic couplings between the high-frequency O-H stretching and the low-frequency intermolecular O...O stretching modes, linear and quadratic distortions of the potential energy of the low-frequency vibrations in the excited state of the O-H stretching vibration, resonance interaction between the two hydrogen bonds in a dimer, and Fermi resonance between the O-H stretching and the overtone of the O-H bending vibrations.

10

Molecular orbital study of hydrated clusters of LiOH

Miyazaki S., Osamura Y.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

|

Vol. 50, No. 4

463-489

EN

The molecular structures of the hydrated species of LiOH, LiOH(H2O)n for n = 1 ~ 5, were studied in terms of density functional B3LYP molecular orbital method. Since the water molecules act as both acid and base toward LiOH, all stable structures located at energy minima are found to be cyclic geometries. The distance between Li+ and OH(-) increases as the number of water molecules increase. Due to the covalent nature of LiOH, the dissociation of LiOH toward Li and OH(-) requires sufficient number of water molecules. Only non-dissociated structures were obtained in the case of a small number of water molecules (n < 3). Even in the case of LiOH(H(2)O)(5), the non-dissociated structures are calculated to be more stable than the dissociated structures. The number of isomers increases substantially with the increase of the number of water molecules. The ionic structures can be classified into contact ion-pair and solvent separated ion-pair structures. The four water molecules can coordinate to Li+ ion and the OH(-) ion can accept three water molecules in most cases. The stabilization energies of hydration for LiOH are calculated to be much larger than those of strong acids such as HCl and H(2)SO(4). The predicted vibrational spectra of each size of clusters indicate an irregular tendency of the stretching frequency of Li-O depending on the number of water molecules.

11

Roughness of amorphous Zn-P thin films

Jarząbek B., Jurusik J., Cisowski J., Nowak M.

Optica Applicata

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2001

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Vol. 31, nr 1

93-101

EN

The effect of thickness variation and the surface roughness of amorphous Zn/sub 32/P/sub 68/ thin films has been investigated by the interference spectroscopy of the optical transmittance and reflectance, as well as by the atomic force microscopy (AFM). The analysis of the optical data allowed determination of the standard deviation of the thin film thickness by taking into account the Gaussian distribution of the change in phase of radiation traversing a thin film. It appears that the value of the standard deviation of the film thickness determined from the optical interference spectroscopy ( sigma /sub w/ approximately=26 nm) is comparable with the value of the mean surface roughness (R/sub a/ approximately=19 nm) evaluated from the AFM studies.

12

Rare earth oxide films: their preparation and characterization

Wiktorczyk T.

Optica Applicata

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2001

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Vol. 31, nr 1

5-33

EN

Summarises the results of our investigations dealing with preparation of rare earth oxide films and examinations of their physical properties. Different deposition methods have been applied for fabrication of these films and rare-earth-oxide-based thin film coatings. The main results concerning film microstructure and optical properties in the wavelength range from the UV up to the IR are presented. Electrical and dielectric studies have been carried out in the time domain and in the frequency domain (from very low frequencies up to radio frequencies) for selected rare earth oxides. MIM sandwich-type structures have been fabricated for this aim. Trapping levels in these oxides have been investigated. The complex impedance diagnostics was applied to the analysis of the volume of the R/sub 2/O/sub 3/ film and interfacial properties (metal/insulator barriers) of M/R/sub 2/O/sub 3//M thin film structures.

13

Anharmonic effects on the OH stretching vibrations of the Na5H3(SeO4)4x2H2O crystal

Ratajczak H., Barnes A. J., Baran J., Marchewka M. K., Yaremko A. M.

Bulletin of the Polish Academy of Sciences. Chemistry

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2001

|

Vol. 49, No. 1

1-8

EN

Polarized infrared spectra of pentasodium trihydrogen tetraselenate dihy-drate, Na(5)H(3)(SeO4)(4)2H(2)O, are analysed using a model which takes account of the Fermi resonance interactions between the OH stretching vibrations and various combination tones. It is demonstrated that the short, centrosymmetric, hydrogen bond of the hydro-gendisefenate anion generates an intense broad absorption whose spectral features can be described taking into consideration strong interaction between the va (OHO) stretching vibration and lattice phonons, while the longer hydrogen bond linking hydrogenselenate ions to the hydrogendiselenate anion gives a typical ABC band structure.

14

Nucleophilic additions in Cu(II), Ni(II), Co(II) pseudohalide-4-halogenopyrazole systems

Hvastijova M., Kohout J., Mroziński J., Jager L.

Polish Journal of Chemistry

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1999

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vol. 73 nr 2

271-278

EN

From M(II)-Y--4-X-pz systems, where M=Cu, Ni, Co; Y=NCO, C(CN)3, N(CN)2; X=Cl, Br, I (pz = pyrazole), new compounds of the type [MY2(4-X-pz)2] and [M(4-X-pz×Y)2] have been prepared. Compounds [M(4-X-pz×Y)2] arise by nucleophylic addition of imine nitrogen from 4-X-pz to cyano carbon of the pseudohalide under formation of five-membered metallocycle. The influence of X substituent on the course of this reaction with various M(II) and Y was investigated. An uncomplete course of nucleophilic addition is revealed by formation of mixed products, consisting of [MY2(4-X-pz)2] and [M(4-X-pz×Y)2]. All compounds were studied by infrared and electronic spectroscopy and probable structures were assigned to the relevant species.

15

The influence of Fermi resonance and of isotopic substitution on the infrared spectra of hydrogen bonded crystals

Ratajczak H., Orville-Thomas W. J., Yaremko A., Ostrovskii D.

Bulletin of the Polish Academy of Sciences. Chemistry

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1999

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Vol. 47, No. 3

193-208

EN

A theoretical approach, which takes into account both the Fermi resonance effect and strong anharmonic interaction between high-frequency v(XH) stretching vibra-tions and the lattice phonons, has been used to explain the IR spectral profiles of NaHF2 , HCrO2 and HCoO2 crystals and their deuterated analogues. Good correlation between the theoretical and experimental spectra has been obtained. It is shown that qualitative changes in the IR spectra of the crystals arising with isotopic substitution are mainly due to the change of the resonance conditions. It is found that in DCrO2 and DCoO2 crystals Fermi resonance is strong, whereas in HCrO2 and HCoO2 materials it is weak.

16

Decomposition of Mg(HSeO3)2x3H2O and Mg(HSeO3)2, IR spectroscopic and thermoanalytical investigations

Engelen B., Muller H., Unterderweide K.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 2

263-268

EN

By crystallization from aqueous Mg(HSeO3)2 solutions, single cristals of Mg(HSeO3)2x3H2O, Mg(HSeO3)2, and MgSe2O5 could be obtained. The compounds have been characterized by means of IR spectroscopy. The dehydration mechanisms of Mg(HSeO3)2x3H2O and Mg(HSeO3)2 have been studied using TG, DTA and high-temperaure Raman techniques. DTA and TG measurements indicate that the thermal decomposition of Mg(HSeO3)2x3H2O results in the direct formation of the diselenite MgSe2O5. High-temperature Raman experiments under quasi static conditions (heating rate<5K/h, isothermal intervals of -1h) show that Mg(HSeO3)2x3H2O decomposes in two steps under the intermediate formation of the anhydrous hydrogenselenite Mg(HSeO3)2.