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Abstract  

A radiation dose assessment exercise was carried out for the Ipomea batata, Allium sativum, Dacaus carota, and Solanum tuberosum due to naturally available radionuclide 40K, 238U and 232Th in the Domiasiat area of Meghalaya. The concentration of radionuclides in biota as well as corresponding soil was measured by precipitation method using NaI detector for continuous 12 months. Transfer factor was calculated and was, for 40K(3.96E−05, 3.40E−05, 3.40E−05, 2.70E−05), for 232Th(3.94E−05, 3.20E−05, 3.20E−054.93E−05), for 238U(3.60E−05, 3.89E−05, 3.85E−054.57E−05), respectively in each biota due to each radionuclide. The point source dose distribution (source ↔ target) hypotheses was applied for the consideration of absorbed fraction. The generated data were modeled using the FASSET method and obtained dose was 8.42E−03, 8.36E−03, 7.78E−03, 7.74E−03 μGy h−1, respectively and finally compared with the IAEA and UNSCEAR dataset for screening level dose for terrestrial biota.

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Abstract  

Radiation dose-risk assessment was carried out for cereal species Brassica compestris var. dichotoma, Oryza sativa var. Shalum1, Zea mays, Lactuca indica, Cumunis sativum, and Clocasia esculanta due to naturally available radionuclides 40K, 238U and 232Th in Domiasiat area. The activity in biota and corresponding soil was measured by precipitation method using NaI(TI) detector. Transfer factor (TF) was for Oryza spp. (1.00E−01-40K, 8.76E−05-232Th, and 9.11E−05-238U), for Brassica spp. (5.39E−01-40K, 8.17E−04-232Th and 2.96E−04-238U) and for Zea spp. (3.41E−01-40K, 5.84E−05-232Th, 8.87E−05-238U) etc., respectively. A detailed physio-morphological study of the biota and extensive investigation of ecosystem was carried out for assessment. The data was modeled using FASSET for dose estimation and obtained total dose was 1.58E−04 
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in Oryza spp., 2.87E−04 
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Brassica spp. and 6.90E−03 
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in Zea spp. etc. The dose was compared with the UNSCEAR dataset for screening level dose for biota. Zea spp. was more susceptible for the chronic radiation exposure.
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Two species of Lejeuneaceae, Drepanolejeunea spicata and Lejeunea stevensiana have been reported for the first time from Arunachal Pradesh and Meghalaya, respectively. Both the species are poorly known in Indian bryoflora. Till now, the former one is known in India only through collection made by W. Giffith (JE-H3412) from an unknown locality of Assam, while the latter one has limited distribution in India and is known from Kerala, Sikkim and Darjeeling only. The detailed taxonomic descriptions and line drawing illustrations of both the species have been presented to assist with their future identification.

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A simple, rapid, and sensitive HPTLC method has been developed for determination of anticancer agent nimbolide in herbal extracts of Azadirachta indica . Samples were applied directly to silica gel 60 F 254 HPTLC plates as stationary phase. Plates were developed to a distance of 85 mm in a glass twin-trough chamber with ethyl acetate-hexane 5:5 ( v/v ) as mobile phase at room temperature (25 ± 2°C). This system was found to give compact spots for nimbolide ( R F 0.49 ± 0.02) for quantities in the range 2–20 μg. Densitometric analysis of nimbolide was carried out in the absorbance mode at 254 nm. Linear regression analysis data for the calibration plots showed a good linear relationship with r = 0.9997. The limits of detection and quantification were 3.3 μg and 11.03 μg, respectively. The method was confirmed to be suitable for accurate determination at nimbolide in extracts of neem leaves. Statistical analysis of the data showed that the method is reproducible and selective for the estimation of nimbolide.

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Abstract  

Sorption of some univalent, divalent and trivalent metal ions has been studied on the hydrogen form of titanium arsenate and titanium tungstoarsenate gels as a function of initial solution concentration at pH 5–6. The effect of pH on maximum uptake (Qmax) has also been seen for some representative ions. Sorption of metal ion becomes almost negligible below pH 1.8, with the exception of monovalent cations. Rubidium ions exhibit interesting adsorption behaviour. The data have been compared with the exchange properties of these two inorganic ion exchangers, as reported earlier6,8.

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In order to study the inheritance pattern of morpho-physiological traits in bread wheat, a 10×10 diallel cross, excluding reciprocals was made and grown in a randomized complete block design (RCBD) with three replications. Observations were recorded on Days to 75% flowering (DF), Days to maturity (DM), Duration of reproductive phase (DRP), Plant height (cm) (PH), Effective tiller/plant (TLS), No. of spikelets per spike (SLS), No. of grains per spike (GS), Grain weight per spike (g) (GW), Spike length (cm) (SL), Biological yield per plant (g) (BY), Harvest index (%) (HI), 1000-Grain weight (g) (TGW), Spike density (SD), Canopy temperature depression (°C) (CTD), Chlorophyll intensity (%) (CI), Chlorophyll fluorescence (Fv/Fm) (CF), Protein content (%) (PC), Grain yield per plant (g) (GY). Highly significant differences were observed among the genotypes for all traits. The resulted 45 F1s and their F2s used for study the nature of gene for grain yield and its contributing traits in bread wheat. The result indicated that considerable gene action and average degree of dominance respond to achieving significant result for grain yield and its component traits. In both the generations F1s and F2s, grain yield per plant (g) was governed by non-additive gene action based on combining ability analysis, (σ2 g/σ2 s)0.5 [GCA and SCA variance ratio] and (H1/D)0.5 [Degree of dominance] were exhibited over dominance type average degree of dominance for grain yield and its component traits in both generations. Genetic analyses of the traits confirm the involvement of both additive and non-additive gene effects in governing the inheritance.

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Abstract

Heterobinuclear macrocyclic complexes, i.e. CuCoL 1, CuFeL 2 and CoVL 3, have been synthesized and anchored onto modified carbamate Al2O3 in order to obtain new hybrid supported catalysts. The identities of the supported metal complexes were confirmed by FT–IR, SEM–EDS and AAS. TGA indicated that the catalysts were thermally stable up to 230 °C. These catalysts have been tested for the functionalization of n-hexane with molecular O2. The best result was obtained with CuFeL 2 over Al2O3 (ca. 19% overall conversion; 78% selectivity: hexan-2-one plus hexan-2-ol) and promoted conversion could be obtained with 2-pyrazinecarboxylic acid (as co-catalyst). The effects of various factors (temperature, O2 pressure, reaction time and catalyst concentration) were also investigated in detail. The impact of both C- and O- centred radical traps was also assessed to establish a radical mechanism.

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Internationally co-authored publications may be regarded as an indicator of scientific co-operation between countries and is of interest in science policy. In this study, the extent of international collaboration in Indian science has been estimated from SCI data in 1990 and 1994. We find an increase in collaboration both in terms of output and the extent of the network and significantly higher impact (IF) associated with internationally co-authored papers in several disciplines. However, there was no significant increase in IF of collaborative papers over time, whereas Indian papers in general showed a statistically significant, though small, increase in average impact from 1990 to 1994. The bulk of Indian scientific co-operation was with the developed Western nations and Japan, but it was often the smaller countries with a few co-authored papers which showed higher average impact. Co-operation with South Asian countries, initially low, has doubled in four years. By a combination of multivariate data analysis techniques the relative positions of India's partners in scientific collaboration have been mapped with respect to the fields of co-operation.

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Abstract  

Before India became an independent country, its scientists and policy makers could foreseethe importance of science in its development, and accordingly a number of research anddevelopment (R&D) institutions were established. However during these five decades ofindependence, the choice between basic sciences and technology was always a subject of debate.It will be appropriate now to examine the changing patterns of Science and Technology (S&T)manpower growth to find out the ground truth reality. The present study pertains to the analysis ofS&T outturn data in various fields of scientific research that can provide a base for S&T planningand policy making. These S&T indicators will be helpful in estimating future requirements, whichin turn can be useful to a great extent in science and technology policy formulation. Theseestimates and future projections are based on mathematical modelling of the data pertaining to theoutturn of highly qualified Scientific and Technical (S&T) personnel in India from differentfaculties over the period 1990-1998. From the trend analysis it is evident that research is no moreperceived as an interesting career except in the field of engineering and medicine. The findingsfurther suggest that there is a noticeable shift from basic sciences to technology.

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An extruded product was made based on oats and dried green pea using central composite rotatable design. Effects of incorporation level of oat flour (OF, 15.86 to 44.14%) and dried green pea flour (DGPF, 7.93 to 22.07%) on the physical and functional characteristics of extruded products based on composite flour were studied using response surface methodology. Second order polynomial equation was used to describe the effect of OF and DGPF on lateral expansion (LE), bulk density (BD), water solubility index (WSI), water absorption index (WAI), and hardness (HD). Results indicated that OF had negative effect on LE, while positive effect on BD, WSI, WAI, and HD. On increasing DGPF, LE and WSI increased, but it had negative effect on BD, WAI, and HD. Numerical optimization resulted in 41.91% OF and 7.93% DGPF to produce acceptable extrudates. The results suggest that oats and dried green pea flour can be extruded with rice flour and corn flour into an acceptable snack food.

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