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P. Mallick, D.K. Mishra, P. Kumar and D. Kanjilal

Abstract

We report the evolution of optical absorption properties of 800 keV Ar ion irradiated NiO thin films through UV-Vis characterization. Our results indicate the existence of both Mott-Hubbard (d → d transition) and charge-transfer (p → d transition) characteristic of NiO. The optical band gap of NiO increases from 3.58 to 3.75 eV when irradiated at the fluence of 5 × 1014 ions cm-2 but it does not show any remarkable variation upon 800 keV Ar ion irradiation at higher fluences. The refractive index and electron polarizability at different ion fluences have been determined from the optical band gap. Both refractive index and electron polarizability follow an opposite trend to that of the energy gap as a function of ion fluence.

Open access

Žarko Mitić, Goran M. Nikolić, Milorad Cakić, Sanja Mitić, Goran S. Nikolić and Stevo Najman

UV-Vis, ATR-FTIR, and EPR. Carbohydr Res 2011; 346: 434–41. https://doi.org/10.1016/j.carres.2010.12.011 4. Rudd TR, Skidmore MA, Guimond SE, et al. Site-specific interactions of copper(II) ions with heparin revealed with complementary (SRCD, NMR, FTIR and EPR) spectroscopic techniques. Carbohydr Res 2008;343: 2184–93. https://doi.org/10.1016/j.carres.2007.12.019 5. Ilić Lj, Ristić S, Cakić M, et al. Polynuclear complex Fe(III) with pullulan oligomers, process of its obtaining, and pharmaceutical preparations on the basis of the complex. EP 1363951 (A

Open access

Goran Stojković, Elizabeta Dimitrieska-Stojković, Marija Soklevska and Romel Velev

. Shamsa, F., Amani, L. (2006). Determination of sulfamethoxazole and trimethoprim in pharmaceuticals by visible and UV spectrometry, Iran. J. Pharm. Res. 1, 31-36. 4. Reisberg, B., Herzog, J., Weinstein, L. (1967). In vitro antibacterial activity of trimethoprim alone and in combination with sulfonamides. Antimicrob. Agents Chemother., 424-426. 5. El-Ansary, A.L., Issa, Y.M., Selim, W. (1999). Spectrophotometric determination of trimethoprim in pure form and in pharmaceutical preparations using Bromthymol blue, Bromocresol green and Alizarin red S. Anal

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Reza Ahmadi, Seyyed Khatiboleslam Sadrnezhad, Rashin Namivandi Zangeneh and Mohammad Ali Oghabian

to the room temperature. The obtained samples were characterized by XRD, UV-Vis absorption and PL spectroscopy. The experimental conditions of preparing the twelve samples used in this study are summarized in Table 1 . Table 1 Experimental conditions of synthesizing samples A1 to A6 and B1 to B6. t [min] → 30 60 90 120 150 180 210 240 T [°C] ↓ 70 A1 A2 A3(S) – A4 A5 A6 – 90 B1 B2 B3 B4 B5 – – B6 2.2 Characterization Structure and florescence properties of the synthesized ZnS

Open access

Raminder Preet Pal Singh, I.S. Hudiara and Shashi Bhushan Rana

synthesized by the chemical precipitation method. Table 3 EDAX data of pure ZnO nanoparticles. Calcination temperature [°C] Zn [%] O [%] 450 92.01 7.99 600 91.69 8.31 750 91.51 8.49 3.3 Optical absorption study Results for pure and doped ZnO nanoparticles were compared by using the UV-Vis absorption spectroscopy. The band gap of semiconductor nanoparticles changes with a change in particle size. The UV-Vis absorption study of pure and Fe-doped ZnO nanoparticles samples has been carried out over the wavelength range of

Open access

Simona Dobrinas, Alina Soceanu, Viorica Popescu and Gabriela Stanciu

Abstract

The aim of this study is to determine the nitrite content in some spices: basil, pepper, dill, thyme, oregano, bay leaves, cinnamon, mint, mustard and cumin. The nitrite content was measured using UV-VIS spectrometric method with Griess reagent. The method was tested and partial validated. The nitrite content varied from 0.23 to 7.7 mg/Kg and these values are lower than those encountered in the literature.

Open access

Gabriela Motan and Aurel Puia

Abstract

Aspirin (acetylsalicylic acid) is an important anti-inflammatory and analgesic-pyretic drug. FTIR and UV-VIS spectroscopy were used in the present study. Using the FTIR spectroscopy and statistical data analysis the correlation between different types of aspirin was determined. The content of acetylsalicylic acid from the analysed samples was determined by the use of UV-VIS spectroscopy

Open access

J. Wojtas, J. Mikolajczyk, M. Nowakowski, B. Rutecka, R. Medrzycki and Z. Bielecki

Applying CEAS method to UV, VIS, and IR spectroscopy sensors

In the paper, several applications of Cavity Enhanced Absorption Spectroscopy (CEAS) for trace mater detection are described. NO2 sensor was constructed using this technique with blue-violet lasers (395-440 nm). The sensor sensitivity reaches the level of single ppb and it was applied in security portal. For detection of two gases at the same time, two-channel sensor was constructed. Used method allows a significant reduction in the cost of optoelectronic CEAS sensor designed to measure of concentrations of many gases simultaneously. Successful monitoring of N2O and NO in the air requires high precision mid-infrared spectroscopy. The constructed sensors are able to measure concentration at ppb level. These sensors might be used for monitoring of atmospheric purity as well as for detection of explosives.

Open access

Alina Soceanu, Simona Dobrinas, Viorica Popescu and Florian Moise

Abstract

The aim of this research is to characterize some distilled drinks commercially available on the market (brandy, gin, vodka, whiskey) and some distilled beverages provided by private manufacturers (palinca made in copper, aluminum and stainless steel distillation apparatus). For this purpose the alcoholic concentration, the dry extract, the total acidity, the ash content and copper level were determined. The alcoholic concentration was measured using the picnometer method and the copper content was determined by UV-VIS molecular absorption spectrometric method. This study shows that the distilled beverages commercially available on the market can be discriminated from palinca, a homemade brandy using the differences between the obtained results.

Open access

Weronika Izydorczyk, Krzysztof Waczyński, Jacek Izydorczyk, Paweł Karasiński, Janusz Mazurkiewicz, Mirosław Magnuski, Jerzy Uljanow, Natalia WaczyńskaNiemiec and Wojciech Filipowski

Abstract

SnO2 nanocrystalline thin films have been deposited on oxidized silicon substrates by spin-coating from a precursor solution, followed by slow thermal annealing in oxygen atmosphere at different temperatures (500 to 900 °C). The precursor solution consisted of 1.0 to 2.0 M SnCl4·5H2O in isopropanol. It was shown that the concentration of the precursor solution, annealing temperature and heating rate had a significant effect on the structural, optical and electrical properties of the studied thin films. The topography of SnO2 thin films was examined by scanning electron microscopy (SEM). Furthermore, as-deposited films were characterized by X-ray diffraction (XRD), UV-Vis and impedance spectroscopy.