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21.
Jinyoung Kim Docheon Ahn Chandramouli Kulshreshtha Kee‐Sun Sohn Namsoo Shin 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(4):i14-i16
The structure of lithium barium silicate, Li2BaSiO4, has been determined from synchrotron radiation powder data. The title compound was synthesized by high‐temperature solid‐state reaction and crystallizes in the hexagonal space group P63cm. It contains two Li atoms, one Ba atom (both site symmetry ..m on special position 6c), two Si atoms [on special positions 4b (site symmetry 3..) and 2a (site symmetry 3.m)] and four O atoms (one on general position 12d, and three on special positions 6c, 4b and 2a). The basic units of the structure are (Li6SiO13)5− units, each comprising seven tetrahedra sharing edges and vertices. These basic units are connected by sharing corners parallel to [001] and through sharing (SiO4)4− tetrahedra in (001). The relationship between the structures and luminescence properties of Li2SrSiO4, Li2CaSiO4 and the title compound is discussed. 相似文献
22.
A. G. Hedge S. Chandramouli R. S. Iyer I. S. Bhat 《Journal of Radioanalytical and Nuclear Chemistry》1992,158(1):65-74
A power reactor fuel reprocessing plant is in operation at Tarapur. The various processes involved in the plant are: fuel rod cutting, dissolution in nitric acid, separation of plutonium, and handling of separated plutonium. The chemical form of plutonium could be nitrate, TBP complex, or oxide depending upon the nature of the process involved. Possible internal exposure to plant personnel occurs mainly by inhalation and occasionally through a contaminated wound. Occupational workers are regularly monitored for internal contamination by urinary excretion analysis as well as by in-vivo lung counting. This paper presents a follow up study of plutonium elimination in four inhalation exposure cases. 相似文献
23.
M. Amaravathi S. Kanakaraju G. V. P. Chandramouli 《Journal of heterocyclic chemistry》2013,50(2):268-271
A new series of novel covalently connected meso‐tetrakis(3‐azophenyl‐4‐hydroxy‐5‐methoxyphenyl)porphyrins were synthesized by linking azobenzene unit at the meta‐position of the meso‐phenyl group. These are characterized by UV–vis, IR, 1H‐NMR, CHN, and FABMS spectroscopic techniques. All the porphyrin compounds showed a typical high energy Soret band at around 435 nm and azobenzene absorption at around 350 nm in UV–vis spectra. Fluorescence intensity of meso‐tetrakis(3‐(4‐methoxyazophenyl)‐4‐hydroxy‐5‐methoxyphenyl)porphyrin ( 2c ) has been observed to be maximum compared with other azobenzene porphyrins. 相似文献
24.
On sequential watermark detection 总被引:2,自引:0,他引:2
This paper introduces a new watermark detection paradigm based on sequential hypothesis testing. It is shown that this framework leads to significantly faster watermark detection compared with more commonly used detectors. Fundamental issues such as joint design of watermark encoding and detection are addressed within this framework. Theoretical results are validated through experiments. On an average, the proposed framework can detect watermarks 70% faster than popular detectors. We believe that this could potentially have significant impact on many applications such as video watermark detection and searching for watermarks in a large database of digital contents. 相似文献
25.
Murugavel A.K. Ranganathan N. Chandramouli R. Chavali S. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2002,10(1):55-58
The estimation of average-power dissipation of a circuit through exhaustive simulation is impractical due to the large number of primary inputs and their combinations. In this work, two algorithms based on least square estimation are proposed for determining the average power dissipation in complementary metal-oxide-semiconductor (CMOS) circuits. Least square estimation converges faster by attempting to minimize the mean square error value during each iteration. Two statistical approaches namely, the sequential least square (SLS) estimation and the recursive least square estimation are investigated. The proposed methods are distribution independent in terms of the input samples, unbiased and point estimation based. Experimental results presented for the MCNC'91 and the ISCAS'89 benchmark circuits show that the least square estimation algorithms converge faster than other statistical techniques such as the Monte Carlo method and the DIPE 相似文献
26.
Nitrobenzene is found to extract nickel in the presence of 1,10-phenanthroline and Rose Bengal as an ion-association complex [Ni(Phen)(2+)(3):2RB(-)] and not as the complex [Ni(Phen)(2+)(2):2RB(-)] reported earlier as extracted into chloroform. The molar absorptivity of the nitrobenzene extract is markedly higher than that of the chloroform extract. The difference in the composition of the extracted species is very interesting. A general scheme is proposed to explain this difference on the basis of the donicity and dielectric constant of the solvent. Beer's law is obeyed in the range 0.05-1.05 ppm of Ni. Interferences of some cations and anions have been studied. Similar observations apply when 2,2'-bipyridyl is used in place of 1,10-phenanthroline. 相似文献
27.
In this work, Lead Barium Niobate-55 tetragonal tungsten bronze structured ceramics modified with Ce3+ with the stoichiometric formula Pb0.55?(3y/2)CeyBa0.45Nb2O6, where y=0–10 mol% Ce3+, were fabricated through the solid state reaction method and investigated for ferroelectric and pyroelectric properties. Pb0.55?(3y/2)CeyBa0.45Nb2O6 (PBN55) exhibited tetragonal (4mm) tungsten bronze structure. The ferroelectric properties (spontaneous polarization, Ps, remanent polarization, Pr and coercive field, Ec), as a function of Ce3+ concentration, have been reported. The influence of Ce3+ on pyroelectric properties of the PBN55 system has been evaluated. The pyroelectric properties were characterized and discussed as a function of Ce3+. The 6 mol% Ce3+ modified tetragonal PBN55 composition exhibited optimum pyroelectric properties in the series which could be suitable for possible pyroelectric applications. 相似文献
28.
Gangavaram V. M. Sharma Dr. Pendem Nagendar Kallaganti V. S. Ramakrishna Nagula Chandramouli Madavi Choudhary Ajit C. Kunwar Dr. 《化学:亚洲杂志》2008,3(6):969-983
A new three‐residue turn was serendipitously discovered in α/β hybrid peptides derived from alternating C‐linked carbo‐β‐amino acids (β‐Caa) and L ‐Ala residues. The three‐residue β‐α‐β turn at the C termini, nucleated by a helix at the N termini, resulted in helix‐turn (HT) supersecondary structures in these peptides. The turn in the HT motif is stabilized by two H bonds—CO(i?2)–NH(i), with a seven‐membered pseudoring (γ turn) in the backward direction, and NH(i?2)–CO(i), with a 13‐membered pseudoring in the forward direction (i being the last residue)—at the C termini. The study was extended to generalize the new three‐residue turn (β‐α‐β) by using different α‐ and β‐amino acids. Furthermore, the HT motifs were efficiently converted, by an extension with helical oligomers at the C termini, into peptides with novel helix‐turn‐helix (HTH) tertiary structures. However, this resulted in the destabilization of the β‐α‐β turn with the concomitant nucleation of another three‐residue turn, α‐β‐β, which is stabilized by 11‐ and 15‐membered bifurcated H bonds. Extensive NMR spectroscopic studies were carried out to delineate the secondary and tertiary structures in these peptides, which are further supported by molecular dynamics (MD) investigations. 相似文献
29.
B. Prasanna G. V. P. Chandramouli 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2059-2065
8-Methoxy-4-methyl-3-(N-[2′-amino-(1′, 3′,4′)thia/oxa-diazol-5′-yl] substituted methyl)-amino thiocoumarins 6(a–f) and 7(a–f), were synthesized by using the unreported 8-methoxy-4-methyl-3-[N-(2′-oxo-2′-methoxy-1′-substituted ethan-1′-yl) amino thiocoumarins as key intermediates. 相似文献
30.
Y. Chandramouli 《商业与工业应用随机模型》1993,9(4):319-333
A discrete, non-negative integer-valued, stationary point process was proposed by Neuts and Pearce as a model for teletraffic packet streams. We examine a data-analytic approach to develop a monitoring scheme for that point process. Monitoring is a procedure of tracking a stochastic process to identity quickly the development of anomalous situations in the evolution of the point process and to detect the assignable causes to account for such conditions. Numerical results are presented to illustrate the performance of the monitoring scheme. 相似文献