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101.
Alok Srivastava D. Pathania K. K. Swain Nicy Ajith R. Acharya A. V. R. Reddy H. Nayyar 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(2):315-318
The phyto-accumulation efficacy of selenium (Se) from soil by chickpea plant is reported. Chickpea plants were grown in soil having different concentrations (1–4 mg kg?1) of Se. Samples of soil and different parts of chickpea plants in Se rich soil were analyzed for determination of Se concentrations by instrumental neutron activation analysis (INAA). Samples were irradiated in self-serve facility of CIRUS reactor, BARC, Mumbai at a neutron flux of the order of 1013 cm?2 s?1. The gamma activity at 264.7 keV of 75Se (119.8 d) was measured using a 45% relative efficiency HPGe detector coupled to MCA. Dependence of Se distribution in soil and plants on its spiking concentration was evaluated in this work. The Se concentrations determined in plant parts grown in control soil and in soil spiked with Se (4 mg kg?1) are in the range of 0.6–0.8 and 65–68 mg kg?1 respectively. 相似文献
102.
J. S. Brahmaji Rao E. Senthilvadivu N. P. Seshadreesan R. Acharya C. R. Venkatasubramani A. V. R. Reddy 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(1):137-141
The pneumatic fast transfer system position at KAMINI reactor, Indira Gandhi Centre for Atomic Research, India was characterized by determining the epithermal neutron flux shape factor (α) and the sub-cadmium to epithermal neutron flux ratio (f) for k 0-based Neutron Activation Analysis (k 0-NAA). For determination of α value, bare, Cd-ratio and Cd-cover methods were employed using dual and multi monitors namely Au, Zr and Zn. For calculation of f, Au and Zr monitors were used in the case of bare method and Au monitor was used for cadmium ratio and cadmium cover methods. The determined α-value of PFTS indicated a hard epithermal neutron spectrum and the f value indicated about 96 % thermal neutron component. For validation of k 0-NAA method, reference materials namely NIST SRM 1646a (Estuarine Sediment) and BCS Nb-stabilized Stainless Steel (BCS/SS No.261/1) were analyzed. The percentage errors of the determined concentration values of elements were within ±5 % with respect to the certified values and the Z-score values at 95 % confidence level were within ±2 in most of the cases. 相似文献
103.
R. S. Sathyapriya Suma Nair V. Kamesh R. K. Prabhath Madhu Nair R. Acharya D. D. Rao 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(3):387-390
A study was conducted to estimate the thorium concentration in locally grown vegetables in high background radiation area (HBRA) of southern coastal regions of India. Locally grown vegetables were collected from HBRA of southern coastal regions of India. Thorium concentration was quantified using instrumental neutron activation analysis. The samples were irradiated at CIRUS reactor and counted using a 40% relative efficiency HPGe detector coupled to MCA. The annual intake of thorium was evaluated using the consumption data provided by National Nutrition Monitoring Board. The daily intake of 232Th from the four food categories (green leafy vegetables, others vegetables, roots and tubers, and fruits) ranged between 0.27 and 5.352?mBq?d?1. The annual internal dose due to ingestion of thorium from these food categories was 46.8?×?10?8 for female and 58.6?×?10?8?Sv?y?1 for male. 相似文献
104.
Nonlinear Dynamics - The excitations of nonlinear magnetosonic lump waves induced by orbiting charged space debris particles in the Low Earth Orbital (LEO) plasma region are investigated in the... 相似文献
105.
We consider maximin and minimax nonlinear mixed integer programming problems which are nonsymmetric in duality sense. Under weaker (pseudo-convex/pseudo-concave) assumptions, we show that the supremum infimum of the maximin problem is greater than or equal to the infimum supremum of the minimax problem. As a particular case, this result reduces to the weak duality theorem for minimax and symmetric dual nonlinear mixed integer programming problems. Further, this is used to generalize available results on minimax and symmetric duality in nonlinear mixed integer programming. 相似文献
106.
The kinetics of formation, acid-catalysed aquation, ligand isomerisation (CoIIIOSO2+→CoIIISO3+), intramolecular electron-transfer,
and base-catalysed hydrolysis and isomerisation of O-bonded sulphito complexes, cis-[Co(en)2(B)(OSO2–O)]+[B=benzimidazole
(bzimH), N-methylimidazole (N-meim)] and the anation of cis-[Co(en)2(B)OH)]2+ [B=bzimH, N-meim and imH (imidazole)] by oxSO2−3
are reported. Steric acceleration is observed in the formation and acid-catalysed aquation of the O-sulphito complexes. The
ligand isomerisation leads to loss of the monodentate amine with the formation of trans-[Co(en)2(SO3–S)2]− (in an excess of
sulphite). Steric acceleration is more pronounced in the isomerisation and base hydrolysis than in the redox process. The
results indicate cis labilisation of the coordinated O-sulphite.
The [(tetraethylenepentamine)Co(OSO2–O)]+ cation undergoes base hydrolysis 103 times faster than the corresponding (en)2(B)
complexes; base-catalysed ligand isomerisation for the former is not observed unlike in the latter. The anation of cis-[Co(en)2(B)OH]2+
(B=imH, bzimH, N-meim) by SO2−3 in a mild alkali pH range (pH=7.9–9.6) and in an excess of SO2−3, yields exclusively trans-[Co(en)2(SO3–S)2]−
with no evidence for the formation of the cis-[Co(en)2(B)(SO3–S)]+ or its O-sulphito analogue. The intramolecularly generated
amido conjugate base of the sulphite ion-pair, {cis-[Co(en)2(B)OH]2+,SO32−}.41cm{cis-[Co(en)(en-H) (B)- OH2]2+,SO32−}, is
believed to generate a five-coordinate intermediate (TBP) that captures the S-end of SO2−3 selectively from a site trans-to
the amine B so that the amine is labilised by the trans effect of the sulphite. The NH-deprotonated coordinated imidazolate
or benzimidazolate species, cis-[Co(en)2(bzm/im)OH]+, do not undergo anation by SO2−3.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
107.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Bloom P Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Carvalho W Casey D 《Physical review letters》1996,76(13):2222-2227
108.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baarmand MM Baden A Balamurali V Balderston J Baldin B Banerjee S Bantly J Bartlett JF Bazizi K Belyaev A Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Bloom P Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS 《Physical review letters》1996,77(16):3309-3314
109.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Casey D Castilla-Valdez H Chakraborty D 《Physical review letters》1995,74(14):2632-2637
110.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Behnke T Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Callot O Casey D Castilla-Valdez H 《Physical review letters》1995,74(13):2422-2426