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D. Jakubowska, J. Zdunek, M. Kulczyk, J. Mizera and K. J. Kurzydłowski

Abstract

The aim of the present paper was to investigate microstructure and texture evolution of two single crystals and polycrystal of Cu-8.5%at.Al material. All of mentioned samples were deformed by HE to achieve true strain ε = 1.17. For microstructure analyzes observations by transmission electron microscope (STEM) were done. Crystalline size for samples after SPD were determine using XRD method. The global texture measurements were done using Bruker D8 Discover diffractometer equipped in Cr radiation. Microstructure investigations revealed nanocrystalline structure in single crystals with initial orientations <110> and <100> and polycrystalline Cu-8.5%at.Al material after SPD. The global texture measurements have shown the stability of initial orientation of <100> Cu-8.5%at.Al single crystal after HE, whereas the same SPD process strongly brakes up the orientation <110> Cu-8.5%at. Al single crystal.

Open access

M. Suresh, S. Asath Bahadur and S. Athimoolam

Abstract

In the present work, a new organic second order NLO material: L-isoleucinium p-toluenesulfonate monohydrate (LIPT) is synthesized and reported for the first time. The LIPT is crystallized in a non-centrosymmetric monoclinic space group P21. Structural and hydrogen bond nature of the compound is analyzed using single crystal X-ray diffraction studies. The crystal exhibits very good optical properties such as wide optical transparency in the region of 210 nm to 1100 nm and the ultraviolet wavelength emission (λ = 283 nm). The second harmonic generation efficiency is found to be 1.7 times the standard KDP. Good thermal, mechanical properties and low dielectric constant at high frequency range show that the material may be a potential candidate for optoelectronic applications.

Open access

K. Selvarani, R. Mahalakshmi and B. Thanuja

Abstract

Co-crystals of L-phenylalanine hydrochloride (LPAHCl) were grown by slow evaporation technique in the presence of manganese sulphate and cadmium chloride. Crystallinity of the grown crystals was confirmed by single crystal X-ray diffraction. Optical transmission spectra showed very high transmittance in the entire visible region. The cut-off wavelength was observed at 250 nm for both the crystals. The optical band gap energy was found to be 4.37 eV and 4.31 eV for the grown co-crystals of LPAHCl with MnSO4 and CdCl2, respectively. The second harmonic generation of the grown crystals was confirmed by Kurtz and Perry powder SHG method and compared with KDP. The frequency dependent dielectric properties of the co-crystals were studied at different temperatures.

Open access

Nusrat Jahan, Faruque-uz-Zaman Chowdhury and A.K.M Zakaria

Keithley 6514. AC electrical properties were measured using an impedance analyzer (Wayne Kerr 6500B) at room temperature up to 120 MHz. 3. Results and discussion 3.1 Structural study Fig. 1 shows the X-ray diffraction patterns of NiCr x Fe 2−x O 4 ferrites sintered at 1350 °C. The peaks can be indexed to (1 1 1), (2 2 0), (3 1 1), (2 2 2), (4 0 0), (4 2 2), (5 1 1) and (4 4 0) planes. The samples can be identified as a single-phase cubic spinel structure with no extra lines corresponding to any other crystallographic phase. The sharp peaks in the XRD

Open access

I. Md. Zahid, S. Kalaiyarasi, M. Krishna Kumar, T. Ganesh, V. Jaisankar and R. Mohan Kumar

yielded (60 %) crystals with dimension up to 4 × 2 × 2 mm3 in the period of 4–5 weeks ( Fig. 3 ). The grown crystals were kept in safe environment and used for various characterizations to study its physical and chemical properties. Fig. 3 Photograph of as-grown DSDMS single crystal and its prominent planes drawn with WinX-Morph program. 3 Results and discussion 3.1 Crystal structure and morphology The single crystal X-ray diffraction data was recorded by using Bruker Kappa APEX II single crystal X-ray diffractometer. It indicates that the

Open access

Masroor Ahmad Bhat, R. A. Zargar, Anchit Modi, M. Arora and N. K. Gaur

discussion 3.1 XRD study XRD pattern of the YBaCo 4 O 7 sample recorded at ambient temperature shown in Fig. 1 was refined with the Rietveld refinement method using the fullproof program [22] . The refinement confirmed the single phase hexagonal structure with P6 3 mc space group and no evidence for impurities was found within the detection limit of the X-ray diffractometer. The unit cell parameters a and c of prepared YBaCo 4 O 7 are 6.2873 Å and 10.2533 Å respectively, that is very close to the reported values [23] which together with the other parameters

Open access

Ioannis Liritzis, Nikolaos Zacharias, Fahad Al-Otaibi, Ioannis Iliopoulos, Christos Katagas and Mossalam Shaltout

geological origin). 4 Instrumentation & Measurements Prior to any sample preparation the mineralogy was checked by 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

Open access

L. Chandra, J. Chandrasekaran, K. Perumal, B. Babu and V. Jayaramakrishnan

-aminopyridine. Hence, the asymmetric system consists of a protonated 2-aminopyridine mono-ionized with 4-aminobenzoic acid. Previously, Arumanayagam et al. [9] performed optical transmittance, band gap, refractive index, optical conductivity, dielectric and powder SHG studies of these crystals. In this manuscript, additionally to those studies, we present the first investigation of the powder XRD, FT-IR, birefringence, photoconductivity, etching and phase matching properties of APAB. 2 Experimental 2.1 Material synthesis Pure specimens of 2-aminopyridine and 4

Open access

E. Talik, L. Lipińska, A. Guzik, P. Zajdel, M. Michalska, M. Szubka, M. Kądziołka-Gaweł and R.L. Paul

–x M x O 4 , where x = 0.5. The samples were characterized by the following methods: X-ray diffraction (XRD), scanning electron microscopy (SEM/EDX), X-ray photoelectron spectroscopy (XPS) and SQUID magnetometry. XPS was used to examine the chemical composition and oxidation state of the manganese, in particular the Mn 3+ :Mn 4+ ratio, from the deconvolution of the complex Mn3p lines. The size of the grains and crystallites were independently obtained from SEM images and XRD patterns, respectively. In this work, we continue examination of LiMn 2 O 4 substituted

Open access

F.A. Najar, G.B. Vakil and B. Want

hydrogen-containing atmospheres [27] . Crystalline materials in which the structural arrangement allows the motion of alkali ions along specific crystallographic axes has been a prime focus of investigations. In the present work, the anomalous dielectric behavior of LSMH crystals has been reported. It was observed that AC conductivity of the present crystal system is controlled by hopping mechanism. The growth aspect and the characterization studies, such as SXRD, UV-Vis, FT-IR, TGA/DTG, and microhardness of LSMH single crystals have been presented. Some numerical