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101.
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103.
We have proposed some new designs of reversible sequential circuits using NCT gate library and compared them with the earlier
proposals. It has been shown that the present proposals have lower gate complexities and lower number of garbage bits compared
to the earlier proposals. We have addressed some conceptual issues related to the feedback and the choice of gate library.
Further it is shown that the proposed quantum / reversible circuits can be implemented optically. 相似文献
104.
Sarkar A Raha Roy S Kumar D Madaan C Rudrawar S Chakraborti AK 《Organic & biomolecular chemistry》2012,10(2):281-286
1-Methylimidazole exhibits an unusually high efficiency in promoting the reaction of aryl methyl ketones with DMF-DMA to form (2E)-1-aryl-3-dimethylamino-2-propenones which lacks correlation between the catalytic efficiency and the basicity of 1-methylimidazole in comparison to other amines. An unprecedented supramolecular domino catalysis rationalises the lack of correlation between the catalytic efficiency and basicity of the amines. The supramolecular assemblies have been characterized by mass-spectrometric ion fishing. The time-dependent increase/decrease in the concentration (ion current) of the supramolecular species consolidated the mechanism. 相似文献
105.
Two protocols for deterministic secure quantum communication (DSQC) using GHZ-like states have been proposed. It is shown that one of these protocols is maximally efficient and that can be modified to an equivalent protocol of quantum secure direct communication (QSDC). Security and efficiency of the proposed protocols are analyzed and compared. It is shown that dense coding is sufficient but not essential for DSQC and QSDC protocols. Maximally efficient QSDC protocols are shown to be more efficient than their DSQC counterparts. This additional efficiency arises at the cost of message transmission rate. 相似文献
106.
Some computational aspects of the characterization of the complex hydrogen bond network dynamics using power spectral analysis are discussed. In the case of hydrogen-bonded liquids, the tagged molecule potential energy is shown to be a useful quantity for capturing the behavior of the networked liquid on different lengths and time scales. The computation of the tagged potential energy for rigid-body effective pair potentials, such as the TIP5P-E and SPC-E models, is discussed. The more structured nature of the TIP5P-E potential, compared to the SPC/E potential, shows up as differences in the high-frequency librational band of the power spectra of the tagged molecule potential energies. The static distributions of the tagged molecule potential energies are also more structured in the case of TIP5P-E, rather than SPC/E, water. The overall behavior of the key power spectral features remains the same in both the models. The possibility of detailed characterization of the power spectrum, and therefore of the underlying dynamics, using a model-based parametric fitting procedure for the power spectra is also discussed. We show that a parametric fitting can allow one to test alternative models of the dynamics underlying the liquid state dynamics. 相似文献
107.
Subhodip Samanta Pinki Saha Sardar Shyam Sundar Maity Anirban Pal Maitrayee Basu Roy Sanjib Ghosh 《Journal of Chemical Sciences》2007,119(2):175-183
A comparative time-resolved emission studies of several naphtho-crown ethers I–V, where metal ions can be complexed in a predetermined orientation with respect to the naphthalene (Naph) π-plane and naphthalene-linked aza crown ethers (L1 and L2) have been presented. In both the systems, crown ethers and aza
crown ethers, naphthalene fluorescence gets quenched. In the systems I to V, the quenching is mainly due to efficient spin-orbit coupling (SOC) leading to greater population of the lowest triplet state
of naphthalene. This SOC depends on the orientation of the crown ring with respect to the Naph-π-plane. However, in the systems L1 and L2, the quenching is due to photoinduced electron transfer (PET) from nitrogen lone
pair of the aza crown ring to naphthalene moiety and consequent exciplex formation. The results have been interpreted using
the time-resolved emission studies of all the compounds in various solvents, their alkali metal ion complexes, and protonated
ligands. 相似文献
108.
Matiur Rahman Anirban SarkarMonoranjan Ghosh Adinath Majee Alakananda Hajra 《Tetrahedron letters》2014
Benzoquinazolin-2-one derivatives were synthesized by using a catalytic amount of task specific ionic liquid, [1-methyl-3-(4-sulfobutyl)imidazolium-4-methylbenzenesulfonate] through a one-pot multicomponent Biginelli reaction of α-tetralone, aldehyde, and urea/thiourea in excellent yields within a short reaction time. Mechanism studies suggest that the reaction proceeds through iminium intermediate and C2-H of the TSIL plays a major role on its catalytic activity. The catalyst has been reused four times without any significant loss in catalytic activity. Large scale reaction by using this TSIL suggests the applicability of this methodology for bulk synthesis of quinazolinone derivatives. 相似文献
109.
Sankha Chattopadhyay Luna Barua Sujata Saha Das Anirban De Umesh Kumar Arpit Mitra Tapas Mallick Madhusmita Md. Alam Nayer Samarendu Sinha Bharat Ratna Sarkar Shantanu Ganguly Kakali De Malay Kanti Das M. G. R. Rajan 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(2):781-790
Performance study of a computer controlled automated closed cyclic module for the separation and recovery of 99mTc from low specific activity (n, γ) 99Mo using methyl ethyl ketone (MEK) solvent extraction technique named 99Mo/99mTc-TCM-AUTOSOLEX (Technetium automated solvent extraction) Generator is described. The entire system is automated and controlled by a user-friendly PC based graphical user interface that actually supervises process via an embedded system based electronic controller. The average yield of separation of 99mTc was above 85 % and 99Mo breakthrough in 99mTc pertechnetate was <0.002 %. The sodium pertechnetate obtained was a clear solution having pH 6–7, Radiochemical (RC). Purity >99 %, MEK content <0.1 % (v/v), Al and Mo content <10 µg/ml. R. C. Purity of 99mTc-radiopharmaceuticals studied was not less than 96 %. Bio-Quality control studies confirm that sodium pertechnetate obtained was sterile and pyrogen free. Imaging studies in animals and humans with limited radiopharmaceuticals show that the quality of 99mTc-pertechenate obtained in the present module was good enough to do clinical study. 相似文献
110.
Dr. Anirban Bhattacharjee Dr. Murielle Chavarot‐Kerlidou Prof. Jillian L. Dempsey Prof. Harry B. Gray Dr. Etsuko Fujita Dr. James T. Muckerman Prof. Marc Fontecave Dr. Vincent Artero Prof. Guilherme M. Arantes Dr. Martin J. Field 《Chemphyschem》2014,15(14):2951-2958
The reduced CoI states of cobaloximes are powerful nucleophiles that play an important role in the hydrogen‐evolving catalytic activity of these species. In this work we analyze the low‐energy electronic absorption bands of two cobaloxime systems experimentally and use a variety of density functional theory and molecular orbital ab initio quantum chemical approaches. Overall we find a reasonable qualitative understanding of the electronic excitation spectra of these compounds but show that obtaining quantitative results remains a challenging task. 相似文献