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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Pankaj Kumar
,
J. Pattanaik
,
S. Ojha
,
S. Gargari
,
R. Joshi
,
G. Roonwal
,
S. Balakrishnan
,
S. Chopra
, and
D. Kanjilal

Abstract  

An accelerator mass spectrometry (AMS) facility for measurements of 10Be has been developed by upgrading the 15UD Pelletron accelerator at Inter-University Accelerator Centre (IUAC), New Delhi. Details of the up gradation of the facilities and the measurement procedure are described briefly. Chemical processing for the separation of 10Be from manganese nodules and results of recent experiments on 10Be are presented.

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Abstract  

Atmospheric tritium activity was measured regularly around Kakrapar Atomic Power Station (KAPS) since gaseous waste which contains tritium is being released through a 100 m high stack at KAPS site. Data collected shows a large variation of 3H concentration in air, fluctuating in the range of ≤0.2−19.9 Bq·m−3. Significantly, higher tritium levels were measured in samples at the site boundary (1.6 km) of KAPS compared to off-site locations. The atmospheric dilution factor was found to be in the range of 1.1·10−7–2.9·10−7 s·m−3. The scavenging ratio of KAPS site was found to be varying from 0.4·104 to 16.7·104 (Bq·m−3 rain water per Bq·m−3 air). The inhalation dose to a member of general public at different distances (1.6−30 km) from KAPS site was found to be 0.07 μSv·y−1.

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Flavour profiling by descriptive analysis of apple wines fermented with different Saccharomyces cerevisiae strains and natural sources of fermentation with or without nitrogen source addition was carried out. Out of 45 attributes used, 38 were found significant and were employed for further evaluation. Generally, the intensities of many of the descriptors in the apple wines were low. Both the natural sources of fermentation (NSF) imparted different flavours notes like lactic, sharp, acetic and fruity to the wine. “W” strain of Saccharomyces cerevisiae gave wines with higher astringency and phenolic flavours, ethyl acetate like, acetaldehyde like flavour, UCD 505 and UCD 522 fermentated wines were peculiar for more ethanolic, sweety and bitter taste, whereas UCD 595 imparted more phenolic, astringent, sour, and ethanolic flavour notes to the wines. The addition of nitrogen source (irrespective of source of fermentation) reduced the development of some flavours considered undesirable (acetic, amyl alcoholic, fusel alcoholic, vegetative). Addition of nitrogen source enhanced the intensity of some other flavour attributes like ethanolic and phenolic in the wines. Due to the same vinification practices (except for the source of fermentation) some modifications in the flavour attributes of apple wines fermented by natural source of fermentation were recorded. The flavour profile of wines fermented by different sources of fermentation, was also reflected in the chemical characteristics examined. Besides higher fermentability, the addition of nitrogen source also affected the physico-chemical characteristics of the wines and consequently, their flavour profile. Application of Principal Component Analysis (PCA) to the means of flavour scores generated from flavour profiling, weakly separated and characterized the wines fermented by different sources of fermentation but did not differentiate the wines fermented with or without nitrogen source. It is concluded that the descriptors described here can characterize apple wine of different quality attributes. The list of descriptors, concentration of standards and details of the technique have also been described.

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The Indian Himalayan sector is well known to support the diversified bryophyte species and communities due to varied phytoclimatical conditions met within different dissected topographical zones. Many potential wilderness areas are still waiting to be explored in terms of their exuberant bryodiversity. During a bryoexploratory survey of an unexplored high-altitude area in the Garhwal Himalayan region, we came across an interesting rheophytic moss Bryocrumia L. E. Anderson. The genus Bryocrumia is represented in India by two species, viz. B. vivicolor (Broth. et Dixon) W. R. Buck and B. malabarica Manju, Prajitha, Prakashkumar et W. Z. Ma. Both of these pleurocarpous species are known to be confined in the southern part of the country. From the Indian Himalayan sector, this moss genus has never been documented earlier. Recently, B. vivicolor has been reported for the first time from the Tungnath area (2,100–3,000 m above sea level) in the Garhwal region of Uttarakhand state as a new addition to the Western Himalayan moss flora, indicating its new distributional range. This hypnaceous moss was found colonising the slopy, wet, submerged rock surfaces along small streams and seepages in mixed oak forests on way to Tungnath. The key characteristics include its rheophilic habit, stem lacking central strand, variable leaf forms, indistinct double costa and round to obtuse leaf apex with prorate tip cells. The present paper provides taxonomic details of this rare moss, representing its wide geographical distribution in India.

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