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101.
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
102.
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
103.
This paper is concerned with the rate of convergence of the distribution of the maximum likelihood estimators of the arrival
and the service rates in a GI/G/1 queueing system.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
104.
Amit Acharya 《Journal of Elasticity》1999,56(2):95-105
A fairly general sufficient condition for compatibility of the left Cauchy–Green deformation field in three dimensions has
been derived. A related necessary condition is also indicated. The kinematical problem is phrased as a suitable problem in
Riemannian geometry, whence the method of solution emerges naturally. The main result of the paper is general in scope and
provides conditions for the existence of solutions to certain types of overdetermined systems of first-order, quasilinear
partial differential equations with algebraic constraints.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
105.
The kinetics of base hydrolysis of some (aminomonocarboxylato)(tetraethylenepentamine)cobalt(III) complexes, [(tetren)CoO2CR]2+ (R= NH2CH2, pyridine‐2 , NH2CH2CH2, NH2CH(CH3) (αβS isomer); R= NH2CH(CH3) (αβR isomer)), have been investigated in methanol–water media (0–80 vol % MeOH) at 15.0≤t°C≤40.0 (0.02 mol dm−3 NaOH). The second‐order rate constant at zero ionic strength, k2°, increases nonlinearly with XMeOH. The transfer free energy of the initial state and the transition state of the amido conjugate base ([ΔtG (i)](s←w)) for the glycinato‐ and pyridine‐2–carboxylato complexes have been calculated using the solubility data of their picrate salts, pK NH date of their N‐protonated forms, and the k2° values in mixed solvent media. The kinetic solvent effects have been interpreted in terms of preferential solvation of the initial state, transition state, and the solvent structure. The activation enthalpies and entropies varied nonlinearly with XMeOH displaying extrema, which is attributable to the solvent structural effects on these thermodynamic parameters. It is also evident that the mutation process, αβR→αβS isomer for the α‐alaninato complex, where this isomerisation refers to the arrangement of the tetren skeleton around the planar secondary NH is sensitive to the nature of the cosolvent molecules and solvent structure. The mutation process is generally more favorable for the five coordinate amido conjugate bases than the initial state. © 1999 John Wiley & Sons, Inc. Int J Chem Kinet 31: 55–64, 1999 相似文献
106.
Prabal Datta Barua Wai Yee Chan Sengul Dogan Mehmet Baygin Turker Tuncer Edward J. Ciaccio Nazrul Islam Kang Hao Cheong Zakia Sultana Shahid U. Rajendra Acharya 《Entropy (Basel, Switzerland)》2021,23(12)
Optical coherence tomography (OCT) images coupled with many learning techniques have been developed to diagnose retinal disorders. This work aims to develop a novel framework for extracting deep features from 18 pre-trained convolutional neural networks (CNN) and to attain high performance using OCT images. In this work, we have developed a new framework for automated detection of retinal disorders using transfer learning. This model consists of three phases: deep fused and multilevel feature extraction, using 18 pre-trained networks and tent maximal pooling, feature selection with ReliefF, and classification using the optimized classifier. The novelty of this proposed framework is the feature generation using widely used CNNs and to select the most suitable features for classification. The extracted features using our proposed intelligent feature extractor are fed to iterative ReliefF (IRF) to automatically select the best feature vector. The quadratic support vector machine (QSVM) is utilized as a classifier in this work. We have developed our model using two public OCT image datasets, and they are named database 1 (DB1) and database 2 (DB2). The proposed framework can attain 97.40% and 100% classification accuracies using the two OCT datasets, DB1 and DB2, respectively. These results illustrate the success of our model. 相似文献
107.
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
108.
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
109.
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
110.
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