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111.
Zucchi G Murugesan V Tondelier D Aldakov D Jeon T Yang F Thuéry P Ephritikhine M Geffroy B 《Inorganic chemistry》2011,50(11):4851-4856
The synthesis and X-ray crystal structure of the ligand L (4,7-dicarbazol-9-yl-[1,10]-phenanthroline) are reported, as well as those of the molecular complex, [Eu(tta)(3)(L)] (1), (tta = 2-thenoyl trifluoroacetylacetonate). Their photophysical properties have been investigated both in solution and in the solid state. It was shown that the ligands used for designing 1 are well-suited for sensitizing the Eu(III) ion emission, thanks to a favorable position of the triplet state as investigated in the Gd(III) complex [Gd(tta)(3)(L)], (2). The low local symmetry of the Eu(III) ion shown by the X-ray crystal structure of 1 is also revealed by luminescence spectroscopy. Because of interesting volatility and solubility properties, 1 is shown to behave as a real molecular material that can be processed both by thermal evaporation and from solution. When doped in poly(methylmethacrylate) (PMMA), 1 forms air-stable and highly red-emitting plastic materials that can be excited in a wide range of wavelengths from the UV to the visible part of the electromagnetic spectrum (250-560 nm). Absolute quantum yields of 80% have been obtained for films comprising 1-3% of 1. Ellipsometry measurements have been introduced to gain information on physical data of 1. They have been performed on thin films of 1 deposited by thermal evaporation and gave access to the refractive index, n, and the absorption coefficient, k, as a function of the wavelength. A value of 1.70 has been found for n at 633 nm. These thin films also show interesting air-stability. 相似文献
112.
Kiki A. Kurnia M. I. Abdul Mutalib T. Murugesan B. Ariwahjoedi 《Journal of solution chemistry》2011,40(5):818-831
Densities and viscosities were determined for binary mixtures containing the protic ionic liquid bis(2-hydroxyethyl)methylammonium
formate [BHEMF] with methanol, ethanol, and 1-propanol at four different temperatures (293.15, 303.15, 313.15, and 323.15 K)
and atmospheric pressure. Excess molar volume and viscosity deviations for the binary system were calculated. The calculated
results were fitted to a Redlich-Kister equation to obtain the coefficients and estimate the standard deviations between the
experimental and calculated quantities. The negative values of excess volume molar for these mixtures indicate that ion-dipole
interactions and packing between ionic liquids and alcohols are present. The values of viscosity deviation are also negative
over the whole composition range, and their values become less negative as the temperature increases. 相似文献
113.
Farah Alimagham Mieszko Dyliński Anne H. Gelebart Konrad J. Jakubowski Janusz Meylahn Yogesh K. Murugesan 《Liquid Crystals Today》2013,22(1):15-24
Two new 5‐substituted 1,3,4‐thiadiazole‐2‐carboxylate esters have been synthesized via ring closure of appropriate tricarbonyl precursors using Lawesson's reagent. The chemistry described is the first report of such methodology in the organic literature. The new materials display broad smectic C phases and show considerable potential for use in electrooptic display devices. 相似文献
114.
Malyanah M. Taib Abobakr K. Ziyada Cecilia Devi Wilfred Thanapalan Murugesan 《Journal of solution chemistry》2012,41(1):100-111
Densities and refractive indices have been measured for binary mixtures of 1-propyronitrile-3-hexylimidazolium bromide + ethanol
in the temperature range 293.15–323.15 K. From the experimental data the excess molar volume V
E, refractive index deviation Δn
D, and the coefficient of thermal expansion α were calculated and fitted to fifth- and third-order Redlich–Kister type equations, respectively. Using the measured densities,
the apparent molar volumes (V
ϕ
), limiting apparent molar volumes (Vf0V_{\phi}^{0}) and limiting apparent molar expansivities (Ef 0E_{\phi} ^{0}) were also determined and the details are discussed. 相似文献
115.
Murugesan Sankarganesh Jeyaraj Dhaveethu Raja Paul Raj Adwin Jose Gujuluva Gangatharan Vinoth Kumar Jegathalaprathaban Rajesh Ramalingam Rajasekaran 《Journal of fluorescence》2018,28(4):975-985
Biochemically active Cu(II) and Zn(II) complexes [CuL(ClO4)2(1) and ZnL(ClO4)2(2)] have been synthesized from N,N donor Schiff base ligand L derived from4,6-dichloropyrimdine-5-carboxaldehyde with 4-(2-aminoethyl)morpholine. The L, complexes 1 and 2 have been structurally characterized by elemental analysis, 1H-NMR, FTIR, MS, UV-Visible and ESR techniques. The results obtained from the spectral studies supports the complexes 1 and 2 are coordinated with L through square planar geometry. DFT calculations results supports, the ligand to metal charge transfer mechanism can occur between L and metal(II) ions. The antimicrobial efficacy results have been recommended that, complexes 1 and 2 are good anti-pathogenic agents than ligand L. The interaction of complexes 1 and 2 with calf thymus (CT) DNA has been studied by electronic absorption, viscometric, fluorometric and cyclic voltammetric measurements. The calculated Kb values for L, complexes 1 and 2 found from absorption titrations was 4.45?×?104, L; 1.92?×?105, 1 and 1.65?×?105, 2. The Ksv values were found to be 3.0?×?103, 3.68?×?103and 3.52?×?103 for L, complexes 1 and 2 by using competitive binding with ethidium bromide (EB). These results suggest that, the compounds are interacted with DNA may be electrostatic binding. The molecular docking studies have been carried out to confirm the interaction of compounds with DNA. Consequently, in vitro anticancer activities of L, complexes 1 and 2 against selected cancer (lung cancer A549, liver cancer HepG2 and cervical carcinoma HeLa) and normal (NHDF) cell lines were assessed by MTT assay. 相似文献
116.
Hyodo F Subramanian S Devasahayam N Murugesan R Matsumoto K Mitchell JB Krishna MC 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,190(2):248-254
Time-domain (TD) electron paramagnetic resonance (EPR) imaging at 300MHz for in vivo applications requires resonators with recovery times less than 1 micros after pulsed excitation to reliably capture the rapidly decaying free induction decay (FID). In this study, we tested the suitability of the Litz foil coil resonator (LCR), commonly used in MRI, for in vivo EPR/EPRI applications in the TD mode and compared with parallel coil resonator (PCR). In TD mode, the sensitivity of LCR was lower than that of the PCR. However, in continuous wave (CW) mode, the LCR showed better sensitivity. The RF homogeneity was similar in both the resonators. The axis of the RF magnetic field is transverse to the cylindrical axis of the LCR, making the resonator and the magnet co-axial. Therefore, the loading of animals, and placing of the anesthesia nose cone and temperature monitors was more convenient in the LCR compared to the PCR whose axis is perpendicular to the magnet axis. 相似文献
117.
A variety of novel 3-(4-methoxyphenyl)-2-substitutedamino-quinazolin-4(3H)-ones were synthesized by reacting the amino group of 2-hydrazino-3-(4-methoxyphenyl)-quinazolin-4(3H)-one with a variety of alkyl and aryl ketones. The starting material 2-hydrazino-3-(4-methoxyphenyl)-quinazolin-4(3H)-one was synthesized from 4-methoxyaniline. The title compounds were investigated for analgesic, anti-inflammatory and ulcerogenic index activities. While the test compounds exhibited significant activity, compounds 2-(1-methylpropylidene)-hydrazino-3-(4-methoxyphenyl)-quinazolin-4(3H)-one (A1), 2-(1-ethylpropylidene)-hydrazino-3-(4-methoxyphenyl)-quinazolin-4(3H)-one (A2) and 2-(1-methylbutylidene)-hydrazino-3-(4-methoxyphenyl)-quinazolin-4(3H)-one (A3) showed moderately more potent analgesic activity and the compound 2-(1-methylbutylidene)-hydrazino-3-(4-methoxyphenyl)-quinazolin-4(3H)-one (A3) showed moderately more potent anti-inflammatory activity when compared to the reference standard diclofenac sodium. Interestingly the test compounds showed only mild ulcerogenic potential when compared to aspirin. 相似文献
118.
A numerical analysis of convective drying of a 3D porous solid of brick material is carried out using the finite element method
and mass lumping technique. The energy equation and moisture transport equations for the porous solid are derived based on
continuum approach following Whitaker’s theory of drying. The governing equations are solved using the Galerkin’s weighted
residual method, which convert the governing equations into discretized form of matrix equations. The resulting capacitance
matrices are made diagonal matrices by following the classical row-sum mass lumping technique. Hence with the use of the Eulerian
time marching scheme, the final equations are reduced to simple algebraic equations, which can be solved directly without
using an equation solver. The proposed numerical scheme is initially validated with experimental results for 1D drying problem
and then tested by application to convective drying of 3D porous solid of brick material for four different aspect ratios
obtained by varying the cross section of the solid. The mass lumping technique could correctly predict the wet bulb temperature
of the solid under evaporative drying conditions. A parametric study carried out for three different values of convective
heat transfer coefficients, 15, 30 and 45 W/m2 K shows an increased drying rate with increase in area of cross section and convective heat transfer coefficient. The proposed
numerical scheme could correctly predict the drying behavior shown in the form of temperature and moisture evolutions. 相似文献
119.
120.
Murugesan Rajadurai Ayyapparaj Muthuchamy A. Raja Annamalai Dinesh K. Agrawal Chun-Ping Jen 《Molecules (Basel, Switzerland)》2021,26(10)
The effect of molybdenum additions on the phases, microstructures, and mechanical properties of pre-alloyed Ti6Al4V was studied through the spark plasma sintering technique. Ti6Al4V-xMo (where x = 0, 2, 4, 6 wt.% of Mo) alloys were developed, and the sintered compacts were characterized in terms of their phase composition, microstructure, and mechanical properties. The results show that the equiaxed primary alpha and Widmänstatten (alpha + beta) microstructure in pre-alloyed Ti6Al4V is transformed into a duplex and globular model with the increasing content of Mo from 0 to 6%. The changing pattern of the microstructure of the sample strongly influences the properties of the material. The solid solution hardening element such as Mo enhances mechanical properties such as yield strength, ultimate tensile strength, ductility, and hardness compared with the pre-alloyed Ti6Al4V alloy. 相似文献