Wyniki wyszukiwania - BazTech

1

Investigation on optical, electrical and etching properties of 2-aminopyridinium 4-aminobenzoate: A phase matchable organic single crystal for optoelectronic device applications

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

Materials Science Poland

|

2017

|

Vol. 35, No. 1

126--134

EN

NLO active 2-aminopyridinium 4-aminobenzoate (APAB) single crystals were successfully grown by the standard slow evaporation technique. The crystallinity of the grown crystals was analyzed through X-ray diffraction (XRD) measurements. Fourier transform infrared (FT-IR) spectroscopic studies were also performed for the identification of different modes present in the compound. The UV-Vis absorption and transmittance spectra were recorded for the grown crystal and the optical band gap was calculated. Birefringence and etching studies were also carried out. The dielectric study showed that the dielectric constant decreased with an increase in frequency. The photoconductivity study revealed its positive photoconducting nature. Theoretical HOMO LUMO investigations were also made for the crystal. The relative SHG efficiency of the material was investigated by the Kurtz and Perry powder technique. The phase matching property of the crystal was studied through the SHG dependence of average particle sizes.

2

A novel reverse phase high-performance liquid chromatography (RP-HPLC–UV) method for the estimation of alosetron HCl and its validation

Karthik Y., Babu B., Meyyanathan S., Awari V., Krishnaveni N.

Acta Chromatographica

|

2015

|

Vol. 27, no. 2

321--330

EN

A novel simple, sensitive, and rapid isocratic reverse phase high-performance liquid chromatographic (RP-HPLC) method was developed for the quantitative determination of alosetron HCl, a 5-HT3 antagonist used in the treatment of severe irritable bowel syndrome (IBS) in females. The optimized chromatographic separation was achieved using a stationary phase of Phenomenex® kromasil C-18 (250 mm × 4.6 mm; 5 μm particle size) column, and mobile phase of 0.025 M disodium hydrogen orthophosphate buffer, pH adjusted to 3.0 with orthophosphoric acid, and acetonitrile in the ratio of 65:35 (v/v) with a flow rate of 1 mL min. -1 The UV detection was carried out at 217 nm. The developed method provided linear responses within the concentration range 100–2000 ng Ml -1, and regression analysis showed a correlation coefficient value (r2) of 0.997. The HPLC method was validated as per International Conference on Harmonization (ICH) guidelines with respect to selectivity, precision, linearity, and robustness. Limit of detection (LOD) and limit of quantification (LOQ) were found to be 1 ng Ml -1 and 5 ng Ml -1, respectively.

3

Growth and characterization of hexamethylenetetramine crystals grown from solution

Babu B., Chandrasekaran J., Balaprabhakaran S.

Materials Science Poland

|

2014

|

Vol. 32, No. 2

164—170

EN

Organic nonlinear optical single crystals of hexamethylenetetramine (HMT; 10 × 10 × 5 mm3) were prepared by crystallization from methanol solution. The grown crystals were subjected to various characterization techniques such as single crystal XRD, powder XRD, UV-Vis and electrical studies. Single crystal XRD analysis confirmed the crystalline structure of the grown crystals. Their crystalline nature was also confirmed by powder XRD technique. The optical transmittance property was identified from UV-Vis spectrum. Dielectric measurements were performed as a function of frequency at different temperatures. DC conductivity and photoconductivity studies were also carried out for the crystal. The powder second harmonic generation efficiency (SHG) of the crystal was measured using Nd:YAG laser and the efficiency was found to be two times greater than that of potassium dihydrogen phosphate (KDP).

4

Optical, structural and electrical properties of pure and urea doped KDP crystals

Babu B., Chandrasekaran J., Balaprabhakaran S., Ilayabarathi P.

Materials Science Poland

|

2013

|

Vol. 31, No. 1

151-157

EN

Single crystals of good optical quality, made of potassium dihydrogen phosphate (KDP) doped with urea were grown by slow evaporation solution growth technique at a constant temperature of 35 C. Optical absorption and dielectric properties were studied for pure and urea doped KDP crystals. Using powder XRD studies, crystalline nature of pure and urea doped KDP crystals was confirmed. AC conductivity was measured for the grown crystals. DC electrical conductivity and photoconductivity studies were carried out for pure and urea doped KDP crystals and the differences caused by the dopant were also discussed.