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421.
V. Gunasekar B. Divya K. Brinda J. Vijaykrishnan V. Ponnusami K. S. Rajan 《Journal of Sol-Gel Science and Technology》2013,68(1):60-66
The purpose of this study was to develop bio-inspired photocatalyst with solar light activity for textile dye degradation. Three TiO2 samples namely TiO2 (TiO2-A), biotemplated TiO2 (TiO2-B), and enzyme mediated Ag–TiO2 biotemplate (TiO2-C), were developed. The presence of anatase phase of TiO2 and silver in synthesized samples were confirmed using X-ray diffraction, field emission scanning electron microscopy, energy-dispersive spectroscopy, and UV–Vis–NIR spectroscopy. Photocatalytic efficiencies of these photocatalysts were evaluated by studying the oxidation of a commercial reactive dye (reactive black) under solar light irradiation in batch reactors. Photocatalytic efficiencies of the sample were compared using statistical tools like one-way ANOVA and Tukey test. The results confirmed that photocatalytic efficiency of TiO2-C was 40 % higher than that of TiO2-A under solar light irradiation. 相似文献
422.
Ultra-performance liquid chromatography coupled with photodiode-array detection has been used to develop a simple, sensitive, and reproducible reversed-phase method for quantitative determination of fingolimod hydrochloride and all possible process-related impurities. Chromatographic separation was achieved on a Waters Acquity BEH C18 (100 mm × 2.1 mm, 1.7 µm) column. The mobile phase was a gradient prepared from potassium dihydrogen phosphate (20 mM) containing 0.1 % (v/v) triethylamine and adjusted to pH 6.5 with trifluoroacetic acid (component A) and 85:15 (v/v) acetonitrile–water (component B); the gradient program (time (min)/% B) was: 0.01/20, 2.0/20, 6.0/75, 9.0/90, 12.0/90, 14.0/20, 16.0/20; the run time was 16 min and fingolimod hydrochloride and its six impurities were well separated. Eluting compounds were monitored at 220 nm. The method was validated for precision, specificity, linearity, limit of detection, limit of quantification, accuracy, and robustness in accordance with International Conference on Harmonization guidelines. Fingolimod hydrochloride was subjected to oxidative, acid, base, hydrolytic, thermal, and photolytic stress, and analysis was conducted to determine the amounts of related impurities formed. 相似文献
423.
Stability analysis of memristor‐based complex‐valued recurrent neural networks with time delays
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Rajan Rakkiyappan Gandhi Velmurugan Fathalla A. Rihan Shanmugam Lakshmanan 《Complexity》2016,21(4):14-39
This article addresses stability analysis of a general class of memristor‐based complex‐valued recurrent neural networks (MCVNNs) with time delays. Some sufficient conditions to guarantee the boundedness on a compact set that globally attracts all trajectories of the MCVNNs are obtained by utilizing local inhibition. Moreover, some sufficient conditions for exponential stability and the global stability of the MCVNNs are established with the help of local invariant sets and linear matrix inequalities using Lyapunov–Krasovskii functional. The analysis results in the article, based on the results from the theory of differential equations with discontinuous right‐hand sides as introduced by Filippov. Finally, two numerical examples are also presented to show the effectiveness and usefulness of our theoretical results. © 2014 Wiley Periodicals, Inc. Complexity 21: 14–39, 2016 相似文献
424.
Gao J Haas H Wang KY Chen Z Breitenstein W Rajan S 《Magnetic resonance in chemistry : MRC》2008,46(1):17-22
We present here a new method using methoxyphenylacetic acid (MPA) as the chiral derivatizing agent (CDA) for the assignment of absolute configuration of cyclic secondary amines. The MPA amides were prepared using the purification-free 'mix and shake' method. A detailed conformational analysis for the two diastereomeric amides was conducted by 2D NMR experiments and molecular mechanics calculations. We have established that, in the most stable conformation of each syn rotamer of MPA amides, the H-alpha in the MPA moiety is oriented toward the bulky substituent group at the asymmetric carbon in the chiral amine, presumably to avoid steric and/or electrostatic interactions. The observed NMR data were correlated with the conformational model to allow unambiguous assignment of absolute configuration of secondary amines. The results demonstrate that the MPA can be used as a useful CDA in the case of sterically crowded cyclic secondary amines from which the MTPA amides are usually difficult to make. 相似文献
425.
Anwar Ali Mohd Tariq Rajan Patel Firdoos Ahmad Ittoo 《Colloid and polymer science》2008,286(2):183-190
A number of thermodynamic parameters viz. apparent molar volumes, ϕ
v
, partial molar volumes, , transfer volumes, , Falkenhagen coefficients, A, Jones–Dole coefficients, B, free energies per mole of solute, , and per mole of solvent, , molar refraction, R
D
, and limiting molar conductivity, , have been calculated by using the experimentally measured densities, ρ, viscosities, η, refractive indices, n
D
, and specific conductivities, κ, data of glycine (0.02–0.10 m) in 0.01 m aqueous sodium dodecyl sulphate, cetyltrimethylammonium bromide, and triton X-100
(TX-100) solutions at 298.15, 303.15, 308.15, and 313.15 K. The above calculated parameters were found to be sensitive towards
the interactions prevailing in the studied amino acid–surfactant–water systems. Moreover, fluorescence study using pyrene
as a photophysical probe has also been carried out, the results of which support the conclusions obtained from other techniques. 相似文献
426.
Paul Manuel Rajan Bharati Indra Rajasingh Chris Monica M 《Journal of Discrete Algorithms》2008,6(1):20-27
A minimum metric basis is a minimum set W of vertices of a graph G(V,E) such that for every pair of vertices u and v of G, there exists a vertex wW with the condition that the length of a shortest path from u to w is different from the length of a shortest path from v to w. The honeycomb and hexagonal networks are popular mesh-derived parallel architectures. Using the duality of these networks we determine minimum metric bases for hexagonal and honeycomb networks. 相似文献
427.
Md. Imteyaz Ahmad Gaurav Mohanty Lee R. Cambrea Daniel C. Harris Krishna Rajan Mufit Akinc 《Journal of Crystal Growth》2012,343(1):115-121
ZrW2O8 is known for its isotropic negative thermal expansion over a wide of range of temperature from ?272 to 777 °C. However, ZrW2O8 melts incongruently at 1257 °C and is stable only over a short temperature interval between 1105 and 1257 °C. This makes the growth of single crystals a formidable challenge. In order to study the intrinsic properties of this compound, a repeatable, viable single crystal growth strategy is required. Here we report a simple, self-seeding, self-fluxing single crystal growth process which resulted in single crystals of ZrW2O8 up to about 4 mm in size. Grown crystals were characterized by X-ray diffraction (XRD), Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Mechanical properties of the crystals were studied using nanoindentation. 相似文献
428.
Rajan Adhikari Dr. Jan Brox Stephen Massicot Dr. Michael Ruppel Prof. Dr. Norbert Jux Dr. Hubertus Marbach Prof. Dr. Hans-Peter Steinrück 《Chemphyschem》2023,24(17):e202300539
The front cover artwork is provided by the groups of Prof. Dr. Hans-Peter Steinrück and Prof. Dr. Norbert Jux at the Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg. The image shows a mixture of six 2H-tetrakis-(3, 5-di-tert-butyl-phenyl)(x)benzoporphyrins (2H-diTTBP(x)BPs, x = 0, 1, 2-cis, 2-trans, 3, or 4) molecules forming a porous square structure on Ag(111) as observed in scanning tunneling microscopy (STM) at room temperature. Read the full text of the Research Article at 10.1002/cphc.202300355 . 相似文献