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Abstract  

Science in the last few years has become increasingly global and collaborative. The number of internationally coauthored papers has been increasing steadily. We have counted internationally jointly authored papers involving authors from the advanced countries and the Third World countries, usingSCI 1991. We have looked at the number of papers resulting from collaboration among authors residing in the countries of the North (e.g. EC and OECD countries), authors residing in the South (e.g. India and Bangladesh, Mexico and Brazil, China and Pakistan) and papers resulting from collaboration between authors residing in the countries of the South and the North (e.g. India and UK, China and USA). Despite its late start, China has published many more collaborative papers with most Asian countries and the advanced countries of the West except the UK than India — confirming the effectiveness of the open door policy of post-Mao China. Both India and China collaborate with USA much more often in physics than in other areas, followed by clinical medicine. However, India collaborates more with USA in chemistry than China. In Indo-US and Sino-US collaborations, collaborating institutions are mostly universities and institutes of higher learning in India and USA, whereas in China several institutions under the Academies also take part. The percentage of collaborative papers involving authors from India is even smaller than the percentage of journal articles originating from India. In general, papers resulting from international collaboration appear in better journals and are cited more often than papers that are the outcome of local research.

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Abstract  

Determination of trace impurities in zircaloy-2 and tellurium by Spark Source Mass Spectrometry (SSMS) is reported. The advantage of SSMS lies in the fact that along with metallic trace constituents even the nonmetallic impurities and gases including hydrogen can also be determined.

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Abstract  

Detailed investigations have been carried out on the well-known method of spectrophotometric determination of boron particularly in uranium compounds as boron-curcumin complex after extraction into 2-ethyl hexane 1,3-diol (EHD) to understand a number of parameters, which have not been addressed earlier in the literature. These include (i) effect of different acid media on analytical results of boron which are employed for dissolution of nuclear fuel samples, (ii) effect of diluents namely ethyl alcohol and N,N-dimethyl formamide on sensitivity of method which are employed for final dilution, and (iii) studies on loss of boron, if any, during conversion of uranium compounds to U3O8. Based on the present studies, the existing procedure has been suitably modified to improve the sensitivity in the measurements. In addition, this paper also describes about interference studies with Al, Cr, Mg, Ca, Fe, Mn, Mo, F and W and amount of EHD on modified method. Absolute detection limit was found to be 10 ng. The precision and accuracy of the method, is 3% at level 100 ng·g−1 of boron.

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Abstract  

An isotope dilution thermal ionization mass-spectrometric (ID-TIMS) method is described for the determination of Zr in U–Zr–Al and Pu–Zr–Al alloy samples. Problems encountered in the chemical exchange between the zirconium isotopes in the spike and sample, particularly Pu–Zr–Al samples, are discussed and a method has been standardized to eliminate it. Separation of Zr from U, Pu and Al was achieved by employing ion exchange procedures. A precision of better than 1% is possible in the determination of Zr with the method reported here.

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Abstract  

A rotary fluidized bioreactor (RFBR) designed for treatment of wastewater was required to be investigated for its hydrodynamic behaviour and validation of design. A radiotracer investigation was carried out to measure residence time distribution (RTD) of wastewater in the RFBR using 82Br as a radiotracer. The radiotracer was instantaneously injected into the inlet feed line and monitored at the inlet and outlet of the reactor using collimated scintillation detectors connected to a data acquisition system. The measured RTD data was treated and simulated using a tanks-in-series model and model parameters i.e. number of tanks describing the degree of mixing was obtained. The results of the investigation showed no flow abnormalities and the reactor behaved as an ideal continuously stirred-tank reactor at all the operating conditions. Based on the results, the design of the reactor was validated.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Palamalai, S. Mohan, M. Sampath, R. Srinivasan, P. Govindan, A. Chinnusamy, V. Raman, and G. Balasubramanian

Abstract  

Some batches of233U oxide product obtained from the reprocessing treatment of irradiated thorium rods, called J-rods in our plant, have been found to contain thorium as much as 85% and iron above 5% as impurities. This product has to be purified before sending for fabrication of the fuel. The present purification method consists of the following three steps: (1) preferential dissolution of U3O8 as compared to thoria, (2) a novel solvent extraction process, and (3) preferential precipitation of Th as oxalate leaving behind the entire U in the filtrate. Development and application of the present purification method to the above233U oxide proxduct are presented in this paper.

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