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mL of a solution of methanol: H 2 O (1:1) to yield a light red solution. Two liquids were mixed and stirred for 1 h to produce a gel of bluish-purple color. After aging for 24 h, the gel was dried at room temperature and then it was dried at 60 °C for 2 h and calcined at 450 °C for 3 h. Crystal structure of Co/TiO 2 nanoparticles was determined with a Bruker diffractometer, CuKα X-ray of wavelength (λ = 1.5406 Å). The XRD patterns were recorded in the 2θ range of 10° to 90° with a step width of 0.02 s −1 . The optical properties of the anatase Co/TiO 2 were

] . The XRD studies have also revealed the increase in the relative increase in AgInSe 2 phase at the expense of AgSbSe 2 phase as earlier discussed. This leads to an increase in the average bond energy and hence, an increase in the optical gap for this system. 4 Conclusions Bulk samples of In x Sb 20_x Ag 10 Se 70 chalcogenides have been synthesized by conventional melt quenching technique and found to be polycrystalline with the formation of tetragonal AgSbSe 2 and AgInSe 2 phases. The composition of the bulk samples have been found to be close to those taken for

ferric ions and octahedral sites are occupied by ferric and nickel ions[ 3 ]. It is suitable as a soft magnetic material in the high frequency region because of its high resistivity and low eddy current loss. This work is an attempt to prepare and study the structural and electrical properties of NiCr x Fe 2−x O 4 ferrites by the gradual replacement of Fe 3+ ions by Cr 3+ ions. The results of XRD, DC and AC resistivity, activation energy, dielectric constant and loss tangent measurements have been described and discussed. 2. Experimental Polycrystalline ferrites

has been proposed by the refinement of its nanostructure and optimizing its morphology [ 14 , 15 ]. Different synthesis techniques of ZnO particles have been reported [ 16 - 20 ]. In this work, we synthesized the Sn doped ZnO nanoparticles using chemical solution method. XRD, FESEM and EDX analyses have been carried out. 2 Experimental 2.1 Synthesis of Sn doped ZnO nanoparticles Sn doped ZnO nanoparticles have been synthesized using a simple chemical solution method. The stock solutions of starting materials 50 mM zinc nitrate Zn(NO 3 ) 2 -2H 2O , 50 mM stannic

References Aparicio P. & Galán E. 1999: Mineralogical interference on kaolinite crystallinity index measurements. Clays and Clay Miner. 47, 12-27. Aparicio P., Galán E. & Ferrell R.E. 2006: A new kaolinite order index based on XRD profile fitting. Clay Miner. 41, 811-817. Bahranowski K., Serwicka E.M., Stoch L. & Strychalski P. 1993: On the possibility of removal of non-structural iron from kao-linite-group minerals. Clay Miner. 28, 379-391. Baláž P. & Kúšik D. (Eds.) 2010: Slovak Minerals Yearbook. Statistical data to 2009. State Geological Institute of

and high magnetic field electrical resistances were measured by using standard four probe method in the temperature range of 5 K ⩽ T ⩽ 300 K, using liquid He coolant cryostat and superconducting magnet. The magnetization measurements were carried out in Zero Field Cooled (ZFC), Field Cooled Warming (FCW) and Field Cooled (FC) as a function of temperature (T) at magnetic field of 1 T using a Quantum Design SQUID magnetometer. The magnetic hysteresis loops were recorded at 3 K, 50 K and 300 K from 0 T to 8 T, respectively. 3 Results and discussion 3.1 XRD study XRD

XRD, then equivalent dose and dose rates were measured. XRD analyses were performed on the same samples (Ain Khodra 8, Gebel Gunna 6) that were used for dating, as well as, from other rock types of local environment shown in Table 1 . Stone was visually similar but mineralogical characterization was decided to be a necessity in order to detect differentiations that potentially point to the exploitations of different quarries and/or different chronological periods of use; checking even small variations was of interest and as a future reference too. Table 1

structural composition of aerogels was studied using the HORIBA Jobin-Yvon Raman spectrometer. 3 Results and discussion Fig. 1 shows the XRD spectra of the asprepared ZnO and Ce-doped ZnO aerogel powders. All the observed peaks are close to those of the polycrystalline ZnO hexagonal wurtzite structure. In the doped aerogel, a peak located at 20 = 28.6°, related to the formation of a second phase caused by cerium atoms is observed. This new peak position is close to the most intense plane (1 1 1) of CeO 2 cubic phase with fluorite structure (JCPDS Card No. 34-394). CeO 2

the mortar samples were divided into two parts: one part for luminescence dating and the other part for XRD measurements. The difficulty to extract pure coarse grain quartz fraction of sufficient quantity from sand used as inert in lime mortar has led the authors to study the luminescent emission from polymineral fine grain phase “enriched in quartz” through HF etching procedures during preparation phase of the samples ( Prasad, 2000 ; Mauz and Lang, 2004 ; Stella et al ., 2013 ). The possibility to use this procedure must be validate by several tests (e

thickness of the films was calculated using a stylus type profilometer (SJ-301). X-ray diffraction patterns and SEM images were obtained using Xray diffractometer (PANalytical-PW 340/60 X’Pert PRO), scanning electron microscope (HITACHI S-3000H), respectively. Optical and electrical studies were performed using UV-Vis-NIR double beam spectrophotometer (LAMBDA-35) and two point probe setup, respectively. 3 Results and discussion Fig. 1 shows the XRD patterns of Sn 2 S 3 thin films prepared with different S:Sn molar concentrations. Fig. 1 XRD patterns of Sn 2 S 3 thin