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1.
Artigo em Inglês | MEDLINE | ID: mdl-23892119

RESUMO

A Nonlinear Optical, good quality, single crystals of doped and undoped l-Alaninium Maleate (LAM) were grown by slow evaporation solution growth technique at room temperature. The lattice parameters were analyzed by single crystal X-ray diffraction technique. The identification of Cadmium ion in the doped crystals was done using the EDAX spectrum. The presence of functional group of the dopant with LAM molecule was studied using FTIR spectra. The results of UV-Vis study is used to compare the transparencies of the doped and undoped LAM crystals. The optical band gap energy of the grown crystal was also calculated. The relative second harmonic generation (SHG) efficiency measurement with KDP reference is used to find the incorporation of metal to l-Alaninium Maleate crystals and the parent material. Also the thermal stability of the grown crystals was studied by TGA/DTA spectrum. The mechanical stability of the grown crystals was confirmed through Vickers micro hardness study. By parallel plate capacitor technique, the dielectric response was studied over a wide range of frequencies at different temperatures. The various studies showed the incorporation of the impurity Cd(2+) into LAM crystals and the investigations indicated that the impurity played an important role in the changes of the spectral and structural properties of LAM crystals.


Assuntos
Alanina/química , Maleatos/química , Metais/química , Alanina/análogos & derivados , Cádmio/química , Cristalização , Eletricidade , Dureza , Íons , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
2.
Artigo em Inglês | MEDLINE | ID: mdl-23571088

RESUMO

Single crystals of bis-thiourea zinc chloride (ZTC) doped with metal ion (Li(+)) possess excellent nonlinear optical properties. These crystals were grown by slow evaporation solution growth technique. The effect of Li(+) dopant on the growth and properties of ZTC single crystal were investigated and reported. The grown crystals were crystallized in orthorhombic structure with non-centro symmetric space group Pn21a through the parent compound. The amount of dopant incorporated in the parent crystal was revealed by the inductively coupled plasma (ICP-OES) studies. The FT-IR spectroscopy study was done for finding and confirming the functional groups present in the compound. The UV-Visible spectral study was carried out to find the optical behavior and transparency nature of the grown crystal. TG/DTA measurements and Vickers microhardness measurements were traced to find out the thermal and mechanical stability of the grown crystals respectively. Using Nd:YAG laser, the Second harmonic generation (SHG) for the grown crystals were confirmed.


Assuntos
Cloretos/química , Lítio/química , Tioureia/análogos & derivados , Compostos de Zinco/química , Cristalização/métodos , Cristalografia por Raios X , Dureza , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
3.
Artigo em Inglês | MEDLINE | ID: mdl-23583879

RESUMO

Undoped and amino acid doped good quality single crystals of Sodium Acid Phthalate crystals (SAP) were grown by slow evaporation solution growth technique which are semiorganic in nature. The effect of amino acid (L-Valine) dopant on the growth and the properties of SAP single crystal was investigated. The single crystal X-ray diffraction studies and FT-IR studies were carried out to identify the crystal structure and the presence of functional groups in undoped and L-Valine doped SAP crystals. The transparent nature of the grown crystal was observed using UV-Visible spectrum. The thermal decomposition of the doped SAP crystals was investigated by thermo gravimetric analysis (TGA) and differential thermal analysis (DTA). The enhancement in the NLO property of the undoped and L-Valine doped SAP crystals using KDP crystal as a reference was studied using SHG measurements. Vickers micro hardness measurements are used for the study of mechanical strength of the grown crystals.


Assuntos
Ácidos Ftálicos/química , Valina/química , Cristalização , Cristalografia por Raios X , Dureza , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
4.
Artigo em Inglês | MEDLINE | ID: mdl-23220671

RESUMO

Potassium Chloride (KCl) as an additive is added into zinc thiourea chloride solution in a small amount (1M%) by the method of slow evaporation solution growth technique at room temperature to get a new crystal. Due to the doping of the impurities on the crystals, remarkable changes in the physical properties were obtained. The grown crystals have been subjected to different instrumentation methods. The incorporation of the amount of potassium and zinc in the crystal lattices has been determined by AAS method. The lattice dimensions have been identified from single crystal X-ray diffraction measurements. The presence of functional group for the grown crystals has been identified by FTIR analysis. The optical, thermal and mechanical behaviors have been assessed by UV-Vis, TG/DTA and Vickers hardness methods respectively. The presence of dislocations of atoms has been identified by etching studies.


Assuntos
Cloretos/química , Cloreto de Potássio/química , Tioureia/química , Compostos de Zinco/química , Cristalização , Cristalografia por Raios X , Dureza , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
5.
Artigo em Inglês | MEDLINE | ID: mdl-22868378

RESUMO

Single crystals of pure bis thiourea zinc acetate (BTZA) and lithium chloride (LiCl) doped BTZA have been synthesized and grown successfully from aqueous solutions by slow evaporation technique. The single crystals thus grown were characterized by different techniques such as single crystal XRD, AAS, FT-IR, UV-Vis, TG/DTA and SHG test. The single crystal XRD study proved that the dopant has not changed the structure of the parent crystal. The AAS study confirmed the presence of lithium in the doped crystal. The FTIR study ascertained the metal coordination of lithium chloride doped BTZA through thiourea. The optical behavior of the doped crystal has been examined by UV spectral analysis. Thermal studies TGA & DTA of the doped crystal have been investigated and found that the doped crystal is thermally more stable than the pure crystal. The SHG test using Nd: YAG Laser confirmed the NLO activity of the pure and doped crystal. The obtained results are presented and discussed.


Assuntos
Cloreto de Lítio/química , Fenômenos Mecânicos , Fenômenos Ópticos , Temperatura , Tioureia/análogos & derivados , Tioureia/química , Acetato de Zinco/química , Cristalografia por Raios X , Análise Diferencial Térmica , Dureza , Dinâmica não Linear , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
6.
Indian J Clin Biochem ; 14(2): 198-206, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23105219

RESUMO

Maple Syrup Urine Disease is an autosomal recessive disorder caused by a deficiency in the activity of the branched-chain α-ketoacid dehydrogenase complex. This rare disorder represents one of the causes of acute neonatal illness which results in devastating disturbances of neurological development. On investigation of 1750 infants with neurological impairment for inborn errors of amino acid metabolism, 4 neonates with classical maple syrup urine disease were detected. These otherwise normal neonates presented in the first week after birth with seizures, lethargy and refusal of feeds, hypoglycemia and metabolic acidosis. The plasma and urine concentrations of the branched-chain amino acids were increased and there was ketoaciduria. Two of these neonates expired before specific treatment could be instituted. Routine biochemical screening of neonates with acute illness could unearth many cases of this rare inherited metabolic disease.

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