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1

Physico chemical properties of irradiated i-SANEX diluents

Mossini E., Macerata E., Giola M., Brambilla L., Castiglioni C., Mariani M.

Nukleonika

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2015

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Vol. 60, No. 4, part 2

893--898

EN

The development of effective processes to recover minor actinides from spent nuclear fuel cannot leave out of consideration the evaluation of the impact of ionizing radiations on safety, fluid dynamics and extraction efficiency. It is common knowledge from the literature that radiation damage mainly affects the diluents and, indirectly, the extractants [1], but a lack of knowledge remains regarding the radiolytic behavior of innovative selective actinide extraction (i-SANEX) diluents [2, 3]. As natural prosecution of the work already performed on diluted nitric acid solutions [4], 0.44 M nitric acid solutions were irradiated in contact with a mixture of kerosene + 5 vol.% 1-octanol by a Co-60 source at 2.5 kGy/h dose rate and up to 100 kGy absorbed dose, conditions of interest for the future industrial facility. Density, viscosity, acidity, nitrate anion concentration and phase transfers were systematically measured before and after γ-irradiation. This was performed because radiation-induced modifi cations of these parameters may induce alterations of both the fluid dynamics and the separation performances of the extracting system. The results suggest that the fluid-dynamics of the system should be unaltered. In fact, only slight alterations of the organic phase viscosity and of the aqueous phase acidity were measured after irradiation, suggesting the occurrence of limited phase transfers and of diluent by-products formation.

2

A DFT study of the effects of Sc doping on electronic and optical properties of CdS nanoparticles

Rehman S. U., Majid A., Hassan N ., Shakoor A., Murtaza G., Khan S. D.

Materials Science Poland

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2015

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Vol. 33, No. 4

782--791

EN

In the present work a systematic study was carried out to understand the influence of Sc doping on electronic and optical properties of CdS nanoparticles. The geometry optimization and symmetry computation for CdS and Sc doped CdS nanoparticles using Density Functional Theory (DFT) on B3LYP level with the QZ4P for Cd and DZ2P for sulphur and Sc were performed by Amsterdam Density Functional (ADF). The results show that HOMO-LUMO gap as well as electronic and optical properties of CdS clusters vary with Sc doping. The HOMO-LUMO gap is affected by the dopant and its value decreases to 0.6 eV. Through considering the numerical integration scheme in the ADF package, we investigated different vibrational modes and our calculated Raman and IR spectra are consistent with the reported result. The calculated IR and Raman peaks of CdS and Sc doped CdS clusters were in the range of 100 to 289 cm−1, 60 cm−1 to 350 cm−1 and 99 cm−1 to 282 cm−1, 60 cm−1 to 350 cm−1, respectively, which was also confirmed by experiment as well as a blue shift occurrence. Subsequently, for deeper research of pure and doped CdS clusters, their absorption spectra were calculated using time-dependent DFT method.

3

A density functional theory study of Raman modes of cadmium hexathiohypodiphosphate (CdPS3)

Shakoor A., Hussain F., Hassan N ., Majid A., Bhatti M. T., Siddique H.

Materials Science Poland

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2015

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Vol. 33, No. 2

286--291

EN

Raman scattering investigations based on density functional theory (DFT) calculations were performed to explore the vibrational modes of a cadmium hexathiohypodiphosphate CdPS3 single crystal. The calculations were performed to obtain the Raman spectra for the cadmium hexathiohypodiphosphate atoms to study the size dependence. Several vibrational modes indicating stretching and bending features related to Cd, S and P atoms were observed. Modifications of the frequency and intensity of different Raman modes with an increase in the number of atoms in CdPS3 were discussed in detail. Hydrogen atoms were added in order to make the closed shell configuration and saturate the CdPS3 as per the requisite for calculating the Raman spectra. This produced some additional modes of vibration related to hydrogen atoms. Band gap and formation energy were also calculated. The results generated are found to be in close agreement with the experimental values.

4

Raman scattering utilization for distributed temperature measurement in optical fibres

Cybulski R., Perlicki K., Siergiejczyk M.

Diagnostyka

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2015

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Vol. 16, No. 3

39--46

EN

Concept of fibre spontaneous Raman scattering utilizing for distributed temperature sensing is presented. Chosen approach uses both backscattered Stokes as reference and anti-Stokes as detection signals. The analysis is carried out towards Stokes and anti-Stokes bands temperature dependence. In order to achieve best measurement accuracy influence of maximum modulation frequency on spatial resolution is verified. Analysed technique allows to calculate temperature along the fibre with 5 m space precision and 1°C temperature precision. Simulations involve 200 m standard single mode fibre in temperatures in range < -5°C , 60°C> with 2x1100 m reference fibre maintained in 22°C.

PL

Koncepcja wykorzystania rozpraszania Ramana we włóknie światłowodowym do rozproszonego pomiaru temperatury została przedstawiona. W wykorzystanym podejściu użyto zarówno światła rozpraszania Stokes’a i anty-Stokes’a odpowiednio jako sygnałów odniesienia i czujnikowego. Analiza opiera się na fakcie zależności rozpraszania w pasmach Stokes’a i anty-Stokes’a od temperatury. W celu optymalizacji jakości pomiaru oceniono wpływ maksymalnej częstotliwości modulacji lasera na przestrzenną rozdzielczość pomiaru. W analizowanym przypadku oraz przy przyjętych wartościach parametrów możliwa jest realizacji pomiaru z dokładnością przestrzenną na poziomie 5 m i temperaturową 1 °C. W symulacjach badany jest odcinek 200 m światłowodu czujnikowego G.652 w temperaturach z zakresu < -5°C , 60°C> oraz dwóch odcinków światłowodu odniesienia od długości 1100 m w temperaturze pokojowej 22°C.

5

A review of the configuration and performance limitation parameters in optical amplifiers

Ab-Rahman M. S.

Optica Applicata

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2014

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Vol. 44, nr 2

251--266

EN

Optical amplifiers are realised in a wide range of applications, such as metro – dense wavelength division multiplexing and cable television networks. These applications require the amplifier to provide a maximum output power level by accepting an input power near the saturation level. To obtain an ideal amplifier according to several parameters, the erbium concentration in the composite core glass, the optimum length of the fibre, the pump saturation and the input signal signaltonoise ratio must be critically studied and addressed. In this paper, we will review the types of optical amplifiers used in communication systems today as well as the parameters that limit the performance of optical amplifiers in the network, such as the noise figure, the gain saturation, the polarisation dependence gain and inhomogeneous broadening effects. Based on the performance limitation factor, we model the amplifier gain profile and the effect of the gain value on the network performance. Finally, we propose various configurations of an optical amplifier, and the advantages of each amplification technique are highlighted.

6

Spectroscopic techniques in the study of human tissues and their components. Part II, Raman spectroscopy

Olsztyńska-Janus S., Gąsior-Głogowska M., Szymborska-Małek K., Komorowska M., Witkiewicz W., Pezowicz C., Szotek S., Kobielarz M.

Acta of Bioengineering and Biomechanics

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2012

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Vol. 14, no. 4

121-133

EN

Among the currently used methods of monitoring human tissues and their components many types of research are distinguished. These include spectroscopic techniques. The advantage of these techniques is the small amount of sample required the rapid process of recording the spectra, and most importantly in the case of biological samples - preparation of tissues is not required. In this work vibrational spectroscopy: ATR-FTIR and Raman spectroscopy will be used. Studies are carried out on tissues: tendons, blood vessels, skin, red blood cells and biological components: amino acids, proteins, DNA, plasma, and deposits.

7

Spectroscopic techniques in the study of human tissues and their components. Part I, IR spectroscopy

Olsztyńska-Janus S., Szymborska-Małek K., Gąsior-Głogowska M., Walski T., Komorowska M., Witkiewicz W., Pezowicz C., Kobielarz M.

Acta of Bioengineering and Biomechanics

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2012

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Vol. 14, no. 3

101-115

EN

Among the currently used methods of monitoring human tissues and their components many types of research are distinguished. These include spectroscopic techniques. The advantage of these techniques is the small amount of sample required, the rapid process of recording the spectra, and most importantly in the case of biological samples - preparation of tissues is not required. In this work, vibrational spectroscopy: ATR-FTIR and Raman spectroscopy will be used. Studies are carried out on tissues: tendons, blood vessels, skin, red blood cells and biological components: amino acids, proteins, DNA, plasma, and deposits.

8

Hydrogen Bonds and Electrostatic Interactions in N-(Ethoxycarbonylmethyl)-quinuclidinium Chloride Dihydrate

Dega-Szafran Z., Katrusiak A., Szafran M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 5

723-735

EN

N-(Ethoxycarbonylmethyl)-quinuclidinium chloride crystallizes as dihydrate, QNBEźClź2H2O. The crystals are monoclinic, space group C2/c. Water molecules interact with the chloride an ions and form a cyclic oligomer, through the O–HźźźCl and O–HźźźO hydrogen bonds. The chloride an ions and water molecules addition ally interact electrostically with the positively charged nitrogen atom of the quinuclidinium moiety. The optimized structure of QNBEźClź2H2O by the B3LYP/6-31G(d,p) level of the ory reproduces well the molecular aggregation observed in the crystal. The FTIR spectrum of the solid compound is consistent with the X-ray structure.

9

Vibrational spectra, electronic excited states and magnetic properties of the copper(II) ions in alkylaminoacetylurea complexes

Ciurla H., Hanuza J., Talik Z., Korabik M., Mrozinski J.

Materials Science Poland

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2009

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Vol. 27, No. 1

5--21

EN

Copper(II) complexes with alkylaminoacetylurea ligands were synthesized and studied by means of IR, Raman, electron absorption and luminescence spectroscopies, as well as by ESR and magnetic methods. The spectroscopic and magnetic studies were performed in the 4-300 K and 1.9-300 K temperature ranges, respectively. The Cu2+ ions in these complexes are four coordinated having distorted squareplanar surroundings. The dependence of the spectroscopic parameters on the alkyl radical of the ligand is discussed. At low temperatures, very weak ferromagnetic interactions are observed for the C3 and C5 alkyls, and an antiferromagnetic one is observed for the remaining complexes, with C4 and C6-C18 alkyls.

10

Reversible electron charge transfer in single-wall carbon nanotubes

Costa S., Bachmatiuk A., Borowiak-Palen E.

Polish Journal of Chemical Technology

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2008

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Vol. 10, nr 2

1-4

EN

Single-wall carbon nanotubes (SWCNT) have proved to be very special materials due to their unique electronic properties. Over the last years many scientists have dedicated their research to the study of the these materials as an electronic system. Amphoteric doping effects (n-type and p-type), which can be reversed, became a very popular way of manipulating the optic and electronic properties of carbon nanotubes. In the particular case of SWCNT, the most common and widely used procedure, which changes their properties, is acid treatment applied as a purification procedure. The effect of the addition of this kind of the dopant has been widely studied but not fully understood so far. Here, we present a study, of two kinds of SWCNT, produced within different techniques: (i) chemical vapors deposition and (ii) laser ablation. The main difference between the two types is the diameter distribution of the obtained materials, which is broad in the first technique and narrow in the second. After the acid treatment it is possible to observe a diameter sensitive doping effect on both samples. Resonance Raman spectroscopy, optical absorption spectroscopy (OAS) in UV/Vis/NIR and the Fourier transform middle-infrared (FTIR) spectroscopy have been applied for the characterization of the samples.

11

Dovyrenite Ca6Zr[Si2O7]2(OH)4 - A New Mineral from Skarned Carbonate Xenoliths in Basic-Ultrabasic Rocks of the Ioko-Dovyren Massif, Northern Baikal Region, Russia

Galuskin Evgeny, Pertsev Nikolai, Armbruster Thomas, Kadiyski Milen, Zadov Aleksander, Galuskina Irina, Dzierżanowski Piotr, Wrzalik Roman, Kislov Evgeny

Mineralogia

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2007

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Vol. 38, iss. 1

15--28

EN

Dovyrenite, simplified formula Ca6Zr[Si2O7]2(OH)4, occurs as an accessory mineral in vein skarns developed in carbonate xenoliths in subvolcanic layered plagiodunite-troctolite series in the Ioko-Dovyren Massif of Proterozoic age, Northern Baikal Region, Buryatia, Russia. Dovyrenite is a late mineral of altered pyroxene and melilite-monticellite skarns. Associated minerals are Zr-bearing phases: fassaitic pyroxene, perovskite and hydrogarnets; and also monticellite, vesuvianite, diopside, foshagite, brucite, calzirtite, tazheranite, baghdadite, apatite, calcite, native bismuth, sphalerite, selenian galena, clausthalite, safflorite, rammelsbergite, pyrrhotite, pentlandite, valleriite, laitakarite, nickeline, nickel-skutterudite. The verage structure of dovyrenite is orthorhombic, space group Pnnm, with subcell parameters A = 5.666(16) , B = 18.844(5) , C = 3.728(11) , V = 398.0(2) 3 and Z = 1. Dovyrenite shows a new type of modular structure with stacking of the tobermorite-like and the rosenbuschite-like layers parallel to (010). Single-crystal structural data point to an incompletely occupied Ca(2) site from the rosenbuschite module which is confirmed by microprobe analyses: ZrO2 16.47, SiO2 32.83, TiO2 0.14, HfO2 0.16, Cr2O3 0.01, CaO 43.87, FeO 0.25, MgO 0.13, MnO 0.02, Nb2O3 0.03; total 99.38 wt% with calculated H2O. The empirical formula is (Ca5.73Fe0.03Mg0.02)5.78(Zr0.98Hf0.01Ti0.01)1Si4(O13.56OH0.44)14(OH)4. The presence of two types of OH group in the dovyrenite structure is corroborated by FTIR and Raman spectroscopy. Dovyrenite is an optically positive biaxial mineral: 1.659(2), 1.660(2); 1.676(2); 2Vz 30(5)° (measured), 28° (calculated).

PL

Nowy minerał dovyrenit Ca6Zr[Si2O7]2(OH)4 został stwierdzony w skarnowanych ksenolitach węglanowych w skałach subwulkanicznych, w obrębie warstwowanego ultrabazytowo-bazytowego Masywu Dovyreńskiego wieku proterozoicznego (Buriatia, Przybajkale Północne, Rosja). Dovyrenit jako minerał akcesoryczny tworzy się kosztem minerałów cyrkonowych oraz minerałów zawierających domieszki cyrkonu, które należą do wczesnych asocjacji skarnów piroksenowych imelilitowo-monticellitowych. Minerały zawierające domieszki cyrkonu reprezentowane są przez piroksen fassaitowy, perowskit oraz hydrogranaty, natomiast z cyrkonowych minerałów rozpoznano kalzyrtit, tazheranit, baghdadyt. W asocjacji z dovyrenitem występują także: monticellit, wezuwian, diopsyd, foshagit, brucit, apatyt, kalcyt, bizmut rodzimy, sfaleryt, saffloryt, rammelsbergit i inne. Ogólna struktura dovyrenitu ma symetrię rombową (grupa przestrzenna Pnnm) z parametrami subkomórki: A = 5,666(16) , B = 18,844(5) , C= 3,728(11) , V = 398,0(2) 3 and Z = 1. Dovyrenit posiada nowy typ struktury modulowanej zbudowanej z warstw podobnych do warstw wyodrębnionych w strukturach tobermorytu oraz rosenbuschitu. Tobermorytopodobne i rosenbuschitopodobne warstwy w strukturze dovyrenitu ułożone są na przemian równolegle do (010). Dane udokładnienia struktury dovyrenitu wskazują na niepełne obsadzenie pozycji Ca(2) w warstwie rosenbuschitopodobnej, co odpowiada danym analizy mikrosondowej: ZrO2 16,47; SiO2 32,83; TiO2 0,14; HfO2 0,16; Cr2O3 0,01; CaO 43,87; FeO 0,25; MgO 0,13; MnO 0,02; Nb2O5 0,03; suma tlenków równa się 99,38%wag.wraz z dodaną H2O obliczeń na podstawie bilansu ładunku. Empiryczny wzór krystalochemiczny dovyrenitu (Ca5,73Fe0,03Mg0,02) 5,78 (Zr0,98Hf0,01Ti0,01) 1Si4(O13,56OH0,44) 14(OH)4 potwierdza niedobór wapnia w pozycji Ca(2) w porównaniu ze wzorem idealnym. Dovyrenit jest minerałem optycznie dodatnim, dwuosiowym: 2Vz 30(5)° (zmierzony), 28° (obliczony); 1,692(2), 1,660, 1,767(2). Parageneza „monticellit-foshagit-dovyrenit” wskazuje na wąski przedział temperaturowy krystalizacji dovyrenitu: 560–630°C w warunkach subwulkanicznych (P < 108 Pa).

12

The effect of poly(ethylene glycol) on the crystallisation and phase transitions of nanocrystalline TiO2 thin films

Djaoued Y., Robichaud J., Brüning R., Albert A. S., Ashrit P. V.

Materials Science Poland

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2005

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Vol. 23, No. 1

15--27

EN

Titanium dioxide (TiO2) films, composed mainly of anatase nanocrystallites, have been obtained from a low temperature poly(ethylene glycol) (PEG) modified sol-gel method. The maximum process temperature in this method is around 90 °C. An addition of PEG in the films accelerates the formation of anatase nanocrystallites. In order to better understand the nature of the influence of PEG on film crystallization, sol-gel solutions were prepared with PEG of different molecular weights (200, 400 and 600). The reference solution without PEG was also prepared. In addition, the influence of different PEG chain lengths on the films' phase transition from anatase to rutile was studied by means of Raman spectroscopy and XRD. Anatase was found to be stable up to 900?1000 °C, depending on the molecular weight of the PEG used in the films.

13

Zastosowanie metod spektroskopowych do badania procesów utwardzania mas ze spoiwem akrylowym

Grabowska B., Holtzer M.

Archiwum Odlewnictwa

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2004

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R. 4, nr 11/1

161--166

PL

Polimery kwasu akrylowego, ze względu na swoje właściwości fizykochemiczne, znalazły zastosowanie w wielu gałęziach przemysłu. W świecie od około 20 lat znane są procesy technologiczne wykorzystujące spoiwo akrylowe utwardzane CO2. Wzrost wymagań związanych z parametrami i technicznymi jak i ekologicznymi oraz ekonomicznymi żywic syntetycznych zmusza do wyjaśnienia procesów towarzyszących reakcjom ich sieciowania. W pracy podjęto próbę wyjaśnienia procesu utwardzania poliakrylanów różnymi czynnikami (kationy metalu/CO2, mikrofale, UV). W tym celu przeprowadzono badania z wykorzystaniem metod spektroskopowych (FTIR, Raman). Dobierano odpowiednio warunki procesu. takie jak: masa cząsteczkowa polimeru, jego lepkość, pH układu, skład masy oraz określono właściwości mechaniczne masy. Z przeprowadzonych badań wynika, że istnieje możliwość termicznego sieciowania poliakrylanów z jednoczesną poprawą właściwości mechanicznych masy. Na widmach (IR, Raman) pojawiają się zmiany wynikające z zastosowania różnych czynników sieciujących. Jednak szczegółowe opracowanie mechanizmu sieciowania żywicy aksylowej różnymi metodami wymaga dalszych szczegółowych badań.

EN

Large variety of applications of the small-molecule, water-soluble, acryl polymers is mainly due to their high chemical reactivity combined with numerous beneficial physical and chemical properties. The polymers are used as binders for moulding sands. The sands are characterised by very low harmful effect to the environment, having at the same time very good technological properties. There is a number of methods used for hardening of the acryl polymer-based binders (CO2, microwave and UV). There were investigated some initial structure transformations which take place in acryl resin system. They were investigated by FTIR and Raman spectrometry. The subjects of studies were resin CP10 and the different hardening processes. Changes in FTIR and Raman spectra during hardening of resins were recorded.

14

Neutron Spectroscopy, IR, Raman and Ab Initio Study of L-Proline

Pawlukojc A., Leciejewicz J., Natkaniec I., Nowicka-Scheibe J.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 1

75-85

EN

Inelastic incoherent neutron scattering spectra (IINS) were obtained for normal and deuterated L-proline. Raman and infrared spectra were also recorded. Geometries were optimized for the zwitterion form using ab initio Hartree-Fock (HF) level with 6-31G*, 6-311G** and 6-311++G** basis sets. Force fields and normal modes were calculated and used as basis for an assignment of the spectral features. The theoretical frequencies of normal and d2 - L-proline were compared with IINS spectra.

15

Crystal Structure and Vibrational Studies of Glycine-LiNO3 and Glycine-NaNO3 Crystals

Baran J., Drozd M., Pietraszko A., Trzebiatowska M., Ratajczak H.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 11

1561-1577

EN

New crystal of glycine with lithium nitrate [(NN3 +CH2COO-)LiNO3; GLiN] was discovered. It belongs to the space group P1 of the triclinic system. Its structure is different from that of the glycine-NaNO3 crystal (GNaN). The Li2O6 units can be distinguished in the GLiN crystal. They have a shape of two symmetry related (through a centre of inversion) tetrahedrons with a common edge. Powder IR and FT-Raman spectra of GLiN and its deuterated analogue and of GNaN were measured and discussed with respect to the crystal structures. The splitting of some vibrations is observed, which suggests the breaking of the selection rules for the centre of inversion.

16

Dimerization of 1,8-Diaminonaphthalene. DFT Theoretical, Ifra-red, raman and Inelastic Neutron Scattering Studies

Majerz I., Pawlukojć A., Sobczyk L., Grech E., Nowicka-Scheibe J.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 2-3

409-417

EN

Infra-red (IR), Raman (R) and inelastic neutron scattering (INS) studies were performed on solid 1,8-diaminonaphthalene. Calculations by using HF and DFT methods showed that very good reproduction of the dimeric structure found in the solid state yields the DFT method on the B3LYP/6-31G** level. The characteristic motif of dimers is an eight-membered ring with two intramolecular (highly bent) and two intermolecular N-H___Nhydrogen bridges. The four outer N-H groups remain non-bonded. This leads to a complicated pattern of vibrational spectra. No agreement between calculated and experimental (IR, R) spectra in the range of (NH2) vibrations was found.Arelatively good coincidence of experimental and theoretically predicted spectra is observed in the middle and low frequency regions, especially when analysing the INS spectra for dimeric species. The dimerization leads to a marked change in modes connected with torsional vibrations of NH2 groups.

17

Reduction in dislocation density and strain in GaN thin films grown via maskless pendeo-epitaxy

Roskowski A. M., Preble E. A., Einfeldt S., Miraglia P. M., Schuck J., Grober R., Davis R. F.

Opto-Electronics Review

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2002

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Vol. 10, No. 4

262-270

EN

Maskless pendeo-epitaxy (PE) involves the lateral and, commonly, the vertical growth of cantilevered “wings” of material from the side-walls of unmasked etched forms. Cross-sectional SEM micrographs revealed that films grown at 1020 C exhibited similar vertical [0001] and lateral [1120] growth rates. Increasing the temperature increased the latter due to the higher thermal stability of the GaN(1120). The (1120) surface was atomically smooth under all growth conditions with an RMS = 0.17 nm. High resolution X-ray diffraction (HRXRD) and atomic force microscopy of the PE films confirmed transmission electron microscopy results regarding the reduction in dislocation density in the wings. Measurement of strain indicated that the wing material is crystallographically relaxed as evidenced by the increase in the c-axis lattice parameter and the upward shift of the E2 Raman line frequency. However, tilting of the wings of ≤ 0.15 occurred due to the tensile stresses in the stripes induced by the mismatch in the coefficients of thermal expansion between the GaN and the underlying substrate.