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Zoran Samard?ijaRID=""ID="" To whom correspondence should be addressed Darko Makovec Miran ?eh 《Mikrochimica acta》2000,132(2-4):383-386
Yttrium-doped BaTiO3 ceramics have been studied as a potential material for positive temperature coefficient resistors (PTCR). The mechanism of
Y incorporation into BaTiO3 plays an important role for displaying good electrical properties. Determination of the amount of yttrium in the BaTiO3 as well as microstructure characterization of the samples were performed using SEM, EDS and WDS analysis. An optimized trace
element WDS quantitative analysis was applied to determine elemental concentrations for Ba, Ti and Y in the samples as accurately
as possible. BaTiO3 and Y2O3 were used as standards. Analysis was undertaken using a JEOL JXA 840A electron probe microanalyzer. WDS X-ray intensity measurements
were performed under 20 kV, 50 nA beam current and 0.2% preset standard counting deviation (σc) using a PET crystal. Measured k-ratios were quantified by ZAF matrix correction. Average results of WDS quantitative analysis showed 20.17 ± 0.08 at % Ti,
19.95 ± 0.09 at % Ba, 0.22 ± 0.03 at % Y, and 59.66 at % O. The results suggest incorporation of yttrium in the BaTiO3 preferentially at the Ba-sites, however partial incorporation of Y at Ti-sites could not be excluded. 相似文献
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M.?Gabriel M.?St?hr R.?M?llerRID=""ID=""Corresponding author. 《Applied Physics A: Materials Science & Processing》2002,74(2):303-305
. The structure of thin 3,4,9,10-perylenetetracarb-oxylic-dianhydride (PTCDA) films on Cu(110) was studied by scanning tunnelling microscopy (STM) from submonolayer to monolayer coverage. While no long-range ordering was found after deposition at room temperature, the formation of a well-defined superstructure is observed after thermal annealing. It appears that the formation of the superstructure is driven by the interaction between the oxygen atoms of the PTCDA and the copper atoms of the substrate. While the distance between the molecules fits well to the atomic lattice of the Cu(110) surface along the [1[`([¯])]1[¯]\bar\Box1\Box]]0] direction, the mismatch along the [001] direction leads to a periodic buckling normal to the surface accompanied by a restructuring of the substrate. 相似文献
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Kumaresh Ghosh Debasis Kar Atanu Panja Ioannis D. Petsalakis Giannoula Theodorakopoulos 《Supramolecular chemistry》2013,25(10-12):856-863
A series of pyridine-coupled benzimidazolium-based receptors 1, 2 and 3 have been designed and synthesised. In the series, only receptor 1 is structurally appealing in the selective recognition of H2PO4? in CHCl3 as well as in CH3CN over a series of other anions. The ratiometric change in emission with a triplet band at 420 nm is the distinctive feature of selective recognition of H2PO4? in CHCl3. In CH3CN, a ‘turn on’ response is selectively observed. Binding studies have been carried out using fluorescence, UV–vis, 1H NMR and 31P NMR spectroscopic techniques. Experimental results have been correlated with the theoretical findings. 相似文献
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Paweł Kozielewicz Petros G. Tsoungas Demeter Tzeli Ioannis D. Petsalakis Mire Zloh 《Structural chemistry》2014,25(6):1711-1723
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Tomohiro?KurataEmail authorView authors OrcID profile Shigeto?Oda Hiroshi?Kawahira Hideaki?Haneishi 《Optical Review》2016,23(6):955-967
We have previously proposed an estimation method of intravascular oxygen saturation \(({\rm SO}_2)\) from the images obtained by sidestream dark-field (SDF) imaging (we call it SDF oximetry) and we investigated its fundamental characteristics by Monte Carlo simulation. In this paper, we propose a correction method for scattering by the tissue and performed experiments with turbid phantoms as well as Monte Carlo simulation experiments to investigate the influence of the tissue scattering in the SDF imaging. In the estimation method, we used modified extinction coefficients of hemoglobin called average extinction coefficients (AECs) to correct the influence from the bandwidth of the illumination sources, the imaging camera characteristics, and the tissue scattering. We estimate the scattering coefficient of the tissue from the maximum slope of pixel value profile along a line perpendicular to the blood vessel running direction in an SDF image and correct AECs using the scattering coefficient. To evaluate the proposed method, we developed a trial SDF probe to obtain three-band images by switching multicolor light-emitting diodes and obtained the image of turbid phantoms comprised of agar powder, fat emulsion, and bovine blood-filled glass tubes. As a result, we found that the increase of scattering by the phantom body brought about the decrease of the AECs. The experimental results showed that the use of suitable values for AECs led to more accurate \({\rm SO}_2\) estimation. We also confirmed the validity of the proposed correction method to improve the accuracy of the \({\rm SO}_2\) estimation. 相似文献
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I. D. Petsalakis 《Molecular physics》2013,111(4):333-342
Ab initio multireference configuration interaction calculations have been carried out on the lower-lying electronic states of BH and their nonadiabatic interactions. The ab initio data have been included in subsequent calculations involving solution of the complex eigenvalue Schrödinger equation to determine predissociation widths and lifetimes of vibrational-rotational levels of these states. Secondly, previously calculated ab initio data on the Rydberg states and their nonadiabatic interactions have been included in multi-state vibrational calculations on the 3p and 3d complexes in BH and BD. The results are in good agreement with the experimental analysis of the 3p and 3d spectra in BH and BD. Furthermore, interaction of the 3d states with the neighbouring 4s state is also found to be important. 相似文献
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Tsubasa?OkamotoEmail authorView authors OrcID profile Hideyuki?Takahashi Eiji?Ohmichi Hitoshi?Ohta 《Applied magnetic resonance》2017,48(5):435-444
We report a novel force-detected high-frequency electron spin resonance (HFESR) technique using a microcantilever in the terahertz region. In this technique, we attach a tiny sample on the microcantilever end and the ESR signal is detected as the cantilever bending. The bending is sensitively detected by fiber-optic Fabry–Perot interferometry. We applied this technique to a tiny amount (~16 ng) of metalloporphyrin, a model substance of hemoproteins, and successfully observed ESR signals at multiple frequencies up to 0.5 THz. This result indicates that the sample volume needed in multi-frequency HFESR can be greatly reduced by several orders of magnitude, and our novel technique would be a promising tool for HFESR studies of metalloproteins in the future. 相似文献
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