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In the seismological research it is very important to use a correct earthquake catalogue that provides a strong basis for indicating seismic sources and for developing seismotectonic models. Homogeneity is expected from the catalogue and desirable to indicate data that are derived from explosions. The spectral analysis provides means to discriminate explosions from earthquakes. The quarry-blasts have simpler spectra than earthquakes. We estimate coda attenuation Q c for quarry-blasts that occurred in Vértes mountains. It has been found that the coda decay rate Q c is significantly lower for quarry-blasts than for earthquakes. At 6 Hz and 10 Hz there are great differences between explosions and earthquakes.

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The Vértes Hills are interesting region in Hungary where small earthquakes with magnitude 2–3 exist among small quarry blasts in a noisy background. A seismological station PKSG (Gánt) works in the middle of Vértes Hills. The main purpose of this paper is to test the different discriminatory elements using the registrations of this single station.The diurnal discrimination of quarry blasts shows a peak time. My purpose is to focus onto these questionable earthquakes — happened in the peak time of the blasts — and be able to identify them.Every discriminant gave “1” if the event was considered to be a blast, and “0” if the event was considered to be an earthquake. The sum of these values shows the level of the separation. The classification of fifteen events was wrong. This is approximately 7 percentage of the dataset.It has been found that the spectral analysis and the correlation of spectra proved to be successful in the discrimination. One type of blast and five types of earthquakes are identified based on the correlation analysis of spectra of S-phases on the horizontal component. The result of the correlation analysis is that most of the spectrum of the blasts were very similar to each others. Correlation analysis has also showed that the big part of earthquakes could be classified into 5 groups. Earthquakes of each group concentrated on different places on the map. The maximum frequency and cepstrum analysis failed.

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Abstract  

The aim of the investigation was to determine whether the 137Cs contamination found in plants around the Paks Nuclear Power Plant in Paks, Hungary was a result of local emission or of the earlier Chernobyl accident. We distinguished between the two possibilities on the basis of the 134Cs/137Cs ratio. The 134Cs activities to be measured were extremely low, in some cases undetectable with conventional evaluation softwares. Therefore a special algorithm was used to determine the 134Cs/137Cs ratio. On the basis of the results it is evident, that the contamination originated from Chernobyl.

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water cycle components need to be understood. Long meteorological records can be examined with statistical methods ( Valipour 2012b ) to look for long-term trends in the time series or with spectral analysis and to study the cyclic variation of

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control at altitude studied by spectral analysis. J. Appl. Physiol. 77, 2537–2542 (1994) Reeves J.T. Sympathetic and parasympathetic indicators of heart rate control at altitude studied by spectral analysis J. Appl

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To understand the structural and thermal properties of the mixed crystals, thermogravimetric (TG) and differential thermal analysis (DTA), and FTIR and Raman spectral studies were carried out for the mixed crystals of Zna/Mgb ammonium sulfate of composition namely 'a' (fraction by mass of salt Zn[NH4]2[SO4]26H2O to the total salt (both Zn[NH4]2[SO4]26H2O, Mg[NH4]2[SO4]26H2O or it can be explained as ZnaMgb[NH4]2[SO4]26H2O, a + b =1), and a = 0.1, 0.25, 0.333, 0.5, 0.666, 0.75 and 0.9 grown by a solution technique. From the correlation and analysis of the results obtained for the various crystals, the desolvation, decomposition, crystalline transition phenomena were identified. By close comparison of the endotherms, obtained for the various crystals, it was found that isomorphous substitution takes place in the crystals. Up to 0.5, Zn2+ ion replaces isomorphous Mg2+ ions in the lattice sites of Mg[NH4]2[SO4]26H2O and above 0.5, Mg2+ ions occupies the Zn2+ ion in the lattice sites of Zn[NH4]2[SO4]26H2O. Both crystals belong to monoclinic system with P 2(1)/a symmetry. The vibrations of NH4 + ion, SO4 2- ion, the complex [Mg(OH2)6]2+ the complex [Zn(OH2)6]2+ and the three different water molecules are identified. The linear distortion of SO4 2- ion is found to be greater than its angular distortion, while the NH4 + ion has suffered more angular distortion. The possibility of free rotation of the NH4 + ion is ruled out.

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Variable temperature /303–553 K/ IR spectroscopic studies are made during thermal decomposition of pure and -treated ammonium perchlorate /AP/. Decomposition is enhanced by radiation or in the presence of an additive /Gd2O3/. Intensity of the stretching /1100 cm–1/ and bending /625 cm–1/ frequencies of ClO 4 decrease on heating the KBr matrix even below 360 K. Above this temperature, a broad band develops over 480–510 cm–1 in the pure and -treated AP which is attributed to ClO 3 / 4/.

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Abstract  

Metal carboxylato-hydrazinates are very good precursors for the synthesis of metal as well as mixed metal oxides as these decompose to nanosized oxides with high surface area most of the times at comparatively lower temperatures. In the present study one such novel precursor nickel manganese fumarato-hydrazinate (NiMn2(C4H2O4)3·6N2H4) has been prepared and characterized by XRD, FTIR and chemical analysis. The thermal decomposition of the precursor has also been studied by isothermal, differential thermal and thermogravimetric analysis. The precursor shows two-step dehydrazination followed by decarboxylation to form NiMn2O4. The infrared spectra show N-N stretching frequency at 965 cm−1, which confirm the bidentate bridging hydrazine. XRD confirms the formation of single phase NiMn2O4.

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Abstract  

As an asymmetric organic molecular crystal, p-N,N-dimethylaminobenzaldehyde (DAB) exhibits peculiar optical property. It was first grown by solution technique adopting slow evaporation method at room temperature using CCl4 as growth medium. The solubility of DAB increases with temperature. Good quality transparent crystals of p-N,N-dimethylaminobenzaldehyde were carefully collected and subjected various characterization studies such as UV, FTIR, 1H and 13CNMR spectral studies and thermal (TG-DTG) studies to determine the purity and application oriented properties of the grown crystals.

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The hyperspectral imaging spectroscopy is a promising future tool in the field of optical remote sensing and it creates new perspective for modern information management in site specific agricultural production. One can determine quantitative relationships between the environmental and physiological parameters of vegetation cover and the soil quality parameters as well as the features of the reflectance spectra by the newgeneration data monitoring and sampling method. These reflectance spectra have characteristics of the different crops and provide with the possibility of accurate classification and detection. The objective was to present the technological capabilities of hyperspectral imaging and show some exprimental results of nutrient sensitive changes in the winter wheat spectra. There were found two characteristic wavelength ranges: the 500 to 800 nm for wheat kernel samples and the 1650 nm to 1800 nm for wheat ear samples where fertilizer treatments showed definite trend on the basis of the normalized reflectance spectra.

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