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Abstract  

Application of charged particle activation analysis (CPAA) for the detection of traces of titanium has been demonstrated. Experimental samples containing traces of titanium varying from ppm to ppb levels were prepared by coprecipitating it with aluminium hydroxide, subsequently converted to Al2O3. Titanium in Al2O3 were irradiated with 40 MeV -particles in the Variable Energy Cyclotron, Calcutta. The element was detected through the product radioisotopes,48V,47Ca,47Sc,51Cr,49Cr and48Cr, produced from various nuclear reactions such as (, pxn), (, xn), etc. Suitability of Al2O3 as diluent matrix for the element has been verified.

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Abstract  

We have studied the feasibility of producing57Co (271.3 d) via the55Mn(
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$^{58} Ni(\alpha ,\alpha n)^{57} Ni\xrightarrow{{36{\mathbf{ }}h}}^{57} Co$$ \end{document}
during the course of producing62Zn by60Ni(, 2n)62Zn reaction. In this case the yield of57Co of reasonable purity has been up to 1 Ci/Ah.
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Abstract  

The synthesis of hydrotalcite-like compounds (HTlcs) containing Mg, Al and Ti using titanium-rich bauxite as one of the starting materials was described. The HT precursors and their calcined products were characterized by powder X-ray diffraction, TG-TDA, FT-IR and surface area measurements. Although the above characterization indicated the formation of hydrotalcite-like structure with good crystallinity, the presence of Ti4+ in the brucite layer was not confirmed. Calcination at 450 °C gave rise mainly to poorly crystalline MgO and amorphous mixed oxides, which can be reconstructed to their original structure by exposure to an aqueous solution. The calcined sample containing titanium showed relatively high adsorption capacity for fluoride and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{Cr}}_{ 2} {\text{O}}_{7}{^{2 - }}$$ \end{document}
as compared to that without titanium.
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Abstract  

Charged particle activation of natural CeO2 with ≈80 MeV16O7+ results in the formation of carrier free isotopes,151, 152, 153Dy and their daughter products,151, 152, 153Tb, in the matrix. The liquid cation exchanger HDEHP, has effectively been utilised as an extractant in the quantitative separation of the activation products namely151, 152, 153Dy,151, 152, 153Tb from the bulk target matrix of ceric oxide.

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Abstract  

The k 0-based internal monostandard neutron activation analysis (IM-NAA) method was used for the analysis of 30 large and non-standard geometry ancient pottery samples obtained from Buddhist sites of Andhra Pradesh, India. One freshly finished pottery and a sun-drenched pottery were also analyzed for comparison. Samples were irradiated in thermal column facility of Apsara reactor and also in graphite reflector position of critical facility of Bhabha Atomic Research Centre. Radioactive assay was carried out using a 40% relative efficiency HPGe detector coupled to MCA. Concentration ratios of 15 elements with respect to Sc were determined. The La/Ce values as well as statistical cluster analysis utilizing concentration ratios of elements were used for grouping/provenance of the potteries.

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Strong anomalies in the concentration of helium, radon and gamma were observed in gases at the geochemical monitoring station, Bakreswar, West Bengal, India, about two weeks before the 7.9 M earthquake at Sichuan, China. The distance between the epicenter of the earthquake and the monitoring site is about 1800 km. This long distance preseismic observation indicates that the radius of influence of large magnitude earthquakes may be substantially large and may cut across plate boundaries. This paper presents the observed geochemical anomalies for the Sichuan earthquake and discusses empirical postulates between earthquake magnitude and its radius of influence.

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Solvent free reactions

Reactions of nitrophenols in 8-hydroxyquinoline–benzoic acid eutectic melt

Journal of Thermal Analysis and Calorimetry
Authors:
Preeti Gupta
,
Tanvi Agrawal
,
S. S. Das
, and
N. B. Singh

Abstract

Reactions of nitrophenols have been studied in the eutectic melt of 8-hydroxyquinoline–benzoic acid, where it reacted with 8-hydroxyquinoline. The reactions were also carried out in solution. The reaction products obtained from both the methods were characterized by FT-IR, differential scanning calorimetry, X-ray diffraction technique and microstructural investigations. The reaction products obtained from eutectic melt were analyzed for C, H, N. The results showed that reaction products obtained from both the methods are same. An attempt has been made to propose the overall mechanism of the reaction in the eutectic melt.

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Abstract  

Presence of thiocyanate ions results in appreciable extraction of Zr(IV) by Aliquat 336 from low aqueous HCl acidities, i.e., 0.1 to 4.5M. The variation of concentrations of HCl, thiocyanate and Aliquat 336 greatly influences the extent of extraction. Mixtures of Aliquat 336 and TOPO result in synergistic extraction of Zr and Hf from acidic thiocyanate media, the extracted species being the disolvate with TOPO. By controlled adjustment of HCl, SCN and Aliquat 336 concentrations, separation of Zr, Nb and Hf is possible. A maximum separation factor (DNb/DZr) of 3675 has been achieved under certain conditions.

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Abstract  

Synergism has been observed in the extraction of zirconium(IV) by mixtures of Aliquat 336 or Alamine 336 with a neutral donor TBP from aq. HCl solutions. Although the extractant dependency for Zr(IV) is found to be nearly second power with respect to TBP alone, monosolvate is found to be formed for extraction by its mixture with Aliquat 336 or Almine 336. Quantitative extraction is observed with mixtures at a lower acidity than that with individual extractants. The species formed is tentatively assigned to be Q2ZrCl6. TBP, where
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$Q{\mathbf{ }} = {\mathbf{ }}R_3 {\mathbf{ }}\mathop N\limits^ + (CH_3 )$$ \end{document}
for Aliquat 336 and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$R_3 {\mathbf{ }}\mathop N\limits^ + H$$ \end{document}
for Alamine 336.
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