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Ion-exchange behaviour of copper ferricyanide

Application of ion-exchange column to the separation of Cs

Journal of Radioanalytical and Nuclear Chemistry
Authors:
Ajay Jain
,
Raj Singh
, and
Chand Bala

Abstract  

A new inorganic ion exchanger, copper ferricyanide prepared by adding copper nitrate to a potassium ferricyanide solution at 80°C has been found to be stable in acids and salt solutions. It has been characterized by chemical analysis, thermogravimetry. X-ray and infrared spectroscopy. Distribution coefficients determined for various metal ions show that the exchanger has a high affinity for heavy univalent cations. The variation of Kd for a number of metal ions as a function of nitric acid concentration and ammonium nitrate has been investigated to elucidate the probable exchange mechanism and to work out conditions for elution. Binary separations of Cs from a number of other metal ions were achieved on the column of exchanger. The exchanger is useful for the separation of137Cs.

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Abstract  

A new inorganic ion-exchanger, zirconium tugnstoarsenate, has been synthesized which has been characterized by chemical analysis, thermogravimetry, X-ray and infrared spectroscopy. The ion exchanger has been found to be stable in acids and neutral salt solutions. The Kd values for 30 metal ions have been determined at pH 3–4 which show that the exchanger has high affinity for UO 2 2+ , ZrO2+, Cs+ and Tl+ ions. The variation of Kd for a number of metal ions as a function of concentration of nitric acid and ammonium nitrate has been investigated to elucidate the probable exchange mechanism and to work out conditions for elution. Some binary separations, viz. Sr2+−Cs+, Sr2+−Rb+, Sr2+−Y3+, Fe3+−Al3+, Fe3+−Zn2+ and Zn2+−Hg2+ in trace amounts have been carried out on the column of the exchanger which demonstrate the utility of the exchanger in radionalytical and analytical chemistry.

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Abstract  

Cerium(IV) molybdate, prepared under the optimum conditions of concentration, acidity etc., shows exchange capacity of 0.96 meq per g of exchanger. The sorption of a large number of metal ions has been investigated and the compound shows promising behaviour as cation exchanger. Numerous separations of analytical and radiochemical interest have been performed on the columns of this exchanger with great efficiency.

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Abstract  

The sorption of univalent, bivalent and trivalent ions has been studied on chromium ferrocyanide gel. The studies reveal a high sorption capacity for Cs+, Tl+, Ag+, Cu2+, Zn2+, Cd2+, Fe3+ and Th4+. The sorption of monovalent cations show purely ion-exchange mechanism while the uptake of bivalent and trivalent cations is non-equivalent in nature. Single elution of Rb+, Cs+ and Tl+ has been performed from the columns of this exchanger and the recovery is almost complete in all the cases. Cu2+ and Ag+ get completely adsorbed on the gel column and their elution is not possible probably due to the formation of some new solid phases. Depending on the Kd values of the metal ions, a large number of separations of radiochemical as well as analytical importance can be performed on the columns of this exchanger material.

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Abstract  

Ion-exchange papers were prepared by impregnating chromatographic Whatman No. 3 paper with pyridinium tungstoarsenate exchanger. The composition of the material loaded on the paper shows that the compound has the formula (C5H5NH)3 W1 2AsO4 0·Rf values of 30 metal ions were determined on these ion-exchange papers by developing with ascending technique in solvents containing mixtures of n-propanol and hydrochloric or nitric acid. Several binary, ternary and some quaternary separations were also achieved on these papers. Studies were also made on plain papers for comparison.

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Abstract

Daffodil (Narcissus tazetta L.) is a bulbous ornamental plant which belongs to the family Amaryllidaceae. It is popular for sweet-smelling beautiful flowers and is used for the fragrant oil and perfumes. It is also a source of alkaloids used in traditional medicines. Daffodil is commercially important ornamental plant, therefore, it is important to maintain its quality and production. Various type of viruses affect daffodil cultivation and among them, potyviruses are of great concern as they cause more economic losses to its commercial cultivation in term of reduction in bulb size, number of bulbs and the quality of daffodil flowers. In this review, a general overview of daffodils, genus Potyvirus, disease symptoms in daffodils linked to potyvirus infection, potyviruses described in daffodils, Potyvirus identification methods and possible management strategies of potyviruses in daffodil cultivation are described in detail. The study will be helpful to daffodil growers for improvement of the production/yield and quality of daffodil crop.

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The free and agar immobilized cells of Nocardia globerula NHB-2 having nitrilase (EC 3.5.5.1) activity were used to catalyse the transformation of benzonitrile to benzoic acid. The whole cells of N. globerula NHB-2 were immobilized in agar which exhibited maximum conversion of benzonitrile to benzoic acid in 0.1 M potassium phosphate buffer pH 7.5 (free cells) 8.0 (immobilized cells), temperature 40 °C, cells 2 mg dcm ml −1 reaction mixture and benzonitrile (4% v/v) in 4 h (free cells). The effect of temperature on the stability of nitrilase was studied and cells retained 100% activity at 30 °C and lost 50% activity at 40 °C. In a fed batch mode of reaction 108 and 84 gl −1 benzoic acid was produced using free and agar entrapped cells (2 g dcm). The agar immobilized cells were recycled up to three times and 80, 62, 20 gl −1 benzoic acid was again produced respectively in each of three cycles and a total 244 g benzoic acid was produced by recycling the same mass of immobilized biocatalyst.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Haladhara Naik
,
Guinyun Kim
,
Ashok Goswami
,
Sarbjit Singh
,
Vijay Manchanda
,
Devesh Raj
,
Srinivasan Ganesan
,
Young Oh
,
Hee-Seock Lee
,
Kyung Kim
,
Man-Woo Lee
,
Moo-Hyun Cho
,
In Ko
, and
Won Namkung

Abstract  

The mass–yield distributions of various fission products have been determined in the 50-, 60- and 70-MeV end point bremsstrahlung induced fission of natPb using off-line γ-ray spectrometric technique in the electron linac at Pohang Accelerator Laboratory, Korea. The mass–yield distributions are symmetric with average mass of 102.34, 102.25 and 102.03 and FWHM of 21, 22 and 23 mass unit, respectively. From the present data and literature data in the 50–85 MeV bremsstrahlung induced fission of 209Bi the following observations were obtained: (i) The average masses of the yield distributions in the 50–85 MeV bremsstrahlung induced fission of natPb and 209Bi are around 102.25 ± 0.25 and 103 ± 0.5, respectively. (ii) The FWHM of the mass–yield distributions increases from about 21 mass units at 50 MeV to 23 mass units at 70–85 MeV, which is explained from the point of increase in multi-chance fission probability with increasing excitation energy. (iii) Within the bremsstrahlung energy range of 50–85 MeV, the role of nuclear structure effect in the mass–yield distribution was observed in the photo-fission of 209Bi, whereas it was not seen in case of natPb. This may be due to the presence of so many isotopes in natPb unlike mono-isotopic 209Bi.

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