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61.
Gavhane Priya D. Kadam Shuddhodan N. Ambhore Ajay N. Dawane Bhaskar S. 《Research on Chemical Intermediates》2021,47(10):3999-4011
Research on Chemical Intermediates - Herein we describe a new convenient strategy for the synthesis of substituted thiazolopyrimidines. The present approach delivers the use of silica-supported... 相似文献
62.
A novel I2-catalyzed one-pot multicomponent protocol for the synthesis of a variety of elusive furo[2,3-b]pyrrole and thieno[2,3-b]pyrrole libraries has been established. To date, cyclization among alkanone, hydrazine and 2-bromobenzofuran or 2-bromobenzo[b]thiophene has not been explored in one-pot. Thus, the proposed single step protocol provides a versatile alternative to existing routes for accessing useful furo[2,3-b]pyrrole and thieno[2,3-b]pyrrole libraries. 相似文献
63.
S. Vishnu Priya J. Herbert Mabel S. Gopalakrishnan M. Palanichamy V. Murugesan 《Journal of molecular catalysis. A, Chemical》2008,290(1-2):60-66
Magnesium aluminophosphate-36 (MAPO-36) molecular sieve was synthesised hydrothermally and subjected to wet ion-exchange with Fe3+, Zn2+, La3+ or Ce3+. They were characterised by using XRD, SEM, temperature programmed desorption (TPD) of ammonia and thermogravimetric analysis (TGA). The XRD patterns of ion-exchanged MAPO-36 exhibit similar features to that of MAPO-36, which revealed no structural degradation during ion-exchange. TPD (ammonia) showed selective ion-exchange of strong acid sites for Fe3+, La3+ and Ce3+ but not for Zn2+. Based on the results of TGA the actual species involved in the ion-exchange is suggested to be M(OH)2+, which upon calcination converted to MO+ where M is Fe3+, La3+ or Ce3+. tert-Butylation of phenol was carried out in the vapour phase as a probe reaction to examine the catalytic activity of MAPO-36 and ion-exchanged MAPO-36 molecular sieves. The ion-exchanged catalysts were found to be more active than the parent MAPO-36 and also showed higher selectivity to 4-tert-butylphenol. 相似文献
64.
Sundaraganesan N Priya M Meganathan C Joshua BD Cornard JP 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,70(1):50-59
In this work, we will report a combined experimental and theoretical study on molecular and vibrational structure of 3,4-dimethoxyaniline (3,4-DMA). The Fourier transform infrared and Fourier transform Raman spectra of 3,4-DMA was recorded in the solid phase. The optimized geometry was calculated by HF and B3LYP methods using 6-31G(d,p) and 6-311++G(d,p) basis sets. The harmonic vibrational frequencies, infrared intensities, Raman scattering activities and the thermodynamic functions of the title compound were performed at and HF/B3LYP/6-311++G(d,p) level of theories. The scaled theoretical wavenumber showed very good agreement with the experimental values. A detailed interpretation of the infrared and Raman spectra of 3,4-DMA was reported. The theoretical spectrograms for IR and Raman spectra of the title molecule have been constructed. 相似文献
65.
G. Vijayakumar S. N. Karthick A. R. Sathiya Priya S. Ramalingam A. Subramania 《Journal of Solid State Electrochemistry》2008,12(9):1135-1141
New poly (vinylidenefluoride-co-hexafluoro propylene) (PVDF-HFP)/CeO2-based microcomposite porous polymer membranes (MCPPM) and nanocomposite porous polymer membranes (NCPPM) were prepared by
phase inversion technique using N-methyl 2-pyrrolidone (NMP) as a solvent and deionized water as a nonsolvent. Phase inversion occurred on the MCPPM/NCPPM
when it is treated by deionized water (nonsolvent). Microcomposite porous polymer electrolytes (MCPPE) and nanocomposite porous
polymer electrolytes (NCPPE) were obtained from their composite porous polymer membranes when immersed in 1.0 M LiClO4 in a mixture of ethylene carbonate/dimethyl carbonate (EC/DMC) (v/v = 1:1) electrolyte solution. The structure and porous morphology of both composite porous polymer membranes was examined
by scanning electron microscope (SEM) analysis. Thermal behavior of both MCPPM/NCPPM was investigated from DSC analysis. Optimized
filler (8 wt% CeO2) added to the NCPPM increases the porosity (72%) than MCPPM (59%). The results showed that the NCPPE has high electrolyte
solution uptake (150%) and maximum ionic conductivity value of 2.47 × 10−3 S cm−1 at room temperature. The NCPPE (8 wt% CeO2) between the lithium metal electrodes were found to have low interfacial resistance (760 Ω cm2) and wide electrochemical stability up to 4.7 V (vs Li/Li+) investigated by impedance spectra and linear sweep voltammetry (LSV), respectively. A prototype battery, which consists
of NCPPE between the graphite anode and LiCoO2 cathode, proves good cycling performance at a discharge rate of C/2 for Li-ion polymer batteries. 相似文献
66.
The matrix isolation technique has been combined with infrared spectroscopy and theoretical calculations to explore the reaction of (CH3)2Zn with O3 over a range of time scales. Upon twin jet deposition, an initial cage pair complex was observed, along with formation of the novel H3COZnCH3 species. Subsequent UV irradiation destroyed the complex and greatly increased the yield of H3COZnCH3. An extensive set of bands were seen for this molecule, and (18)O spectroscopic data were obtained as well. The identification of this species was supported by theoretical calculations at the B3LYP/6-311++g(d,2p) level. Merged jet deposition led to a very different set of products, including H2CO, CH3OH and C2H6, identifications that were confirmed by (18)O substitution. In addition, a new variable length concentric deposition technique was developed to permit study of the time scales between twin (relatively short) and merged (relatively longer) reaction times. Mechanistic inferences for this reaction are discussed. 相似文献
67.
Priya K. Patel 《Molecular Crystals and Liquid Crystals》2016,634(1):41-49
A novel thermotropically mesomorphic, meta-substituted nitro group of chalconyl ester series, RO-C6H4-COO-C6H3-(NO2)-CO-CH=CH-C6H4OC12H25(n) (para) is synthesized and studied with an aim to establish the relation between molecular structure and the mesomorphism with reference to changing molecular flexibility in presence of nitro lateral group. Novel homologous series consist of thirteen homologs (C1–C18) whose mesomorphism commences from C5 homolog as enantiotropic nematogenic with absence of smectic property, even in the monotropic condition. Transition temperatures of novel substances were determined by an optical polarizing microscope, equipped with a heating stage (POM). Textures of a nematic phase are threaded or Schlieren. N-I transition curve exhibited narrow, sharp and short odd-even effect; with deviating trend in a phase diagram. Analytical, spectral and thermal data confirmed the molecular structures of homologs. Thermal stability for nematic is 182.89°C, whose mesophase lengths minimum to maximum ranges from 17°C to 45°C and it is an upper middle ordered melting type series. Group efficiency order for nematic is series 1 > series Y > series X, as derived from comparative study of structurally similar analogous series. 相似文献
68.
Umezawa N Kalia RK Nakano A Vashista P Shimojo F 《The Journal of chemical physics》2007,126(23):234702
We have investigated the decomposition and chemisorption of a 1,3,5-trinitro-1,3,5-triazine (RDX) molecule on Al(111) surface using molecular dynamics simulations, in which interatomic forces are computed quantum mechanically in the framework of the density functional theory (DFT). The real-space DFT calculations are based on higher-order finite difference and norm-conserving pseudopotential methods. Strong attractive forces between oxygen and aluminum atoms break N-O and N-N bonds in the RDX and, subsequently, the dissociated oxygen atoms and NO molecules oxidize the Al surface. In addition to these Al surface-assisted decompositions, ring cleavage of the RDX molecule is also observed. These reactions occur spontaneously without potential barriers and result in the attachment of the rest of the RDX molecule to the surface. This opens up the possibility of coating Al nanoparticles with RDX molecules to avoid the detrimental effect of oxidation in high energy density material applications. 相似文献
69.
Kalaga Mahalakshmi Naidu Rudresh Naik Gajanan Kondapalli Venkata Gowri Chandra Sekhar 《Arabian Journal of Chemistry》2019,12(8):2418-2429
A series of thirty-six novel 5-(2-(4-(benzo[d]isoxazol-3-yl)piperazin-1-yl)acetyl)indolin-2-one and 5-(2-(4-substitutedpiperazin-1-yl)acetyl)indolin-2-one analogues were synthesized, characterized and screened for their in vitro anti-tubercular activity against Mycobacterium tuberculosis H37Rv strain. These compounds exhibited minimum inhibitory concentration between 1.56 and 50 μg/mL. Among these derivatives, compounds 10c, 10d, 10j, 10o and 10v (MIC 6.25 μg/mL) displayed moderate activity, while compounds 10e, 10l, 10q, 10w,10x, 12d, 12e and 12i (MIC 3.12 μg/mL) showed good anti-tubercular activity and compounds 10f, 10k, 10p, 10r, 12f, 12j and 12k (MIC 1.56 μg/mL) exhibited excellent anti-tubercular activity. In addition, MTT assay was accomplished on the active analogues of the series against mouse macrophage (RAW 264.7) cells to evaluate the cytotoxic effect of the newly synthesized compounds and selectivity index of the compounds was determined. 相似文献
70.
Priya Malpani Kishore Thapliyal Nasir Alam Anirban Pathak Venkatakrishnan Narayanan Subhashish Banerjee 《Annalen der Physik》2019,531(11)
Quantum phase properties of photon added and subtracted displaced Fock states (and their limiting cases) are investigated from a number of perspectives, and it is shown that the quantum phase properties are dependent on the quantum state engineering operations performed. Specifically, the analytic expressions for quantum phase distributions and angular Q distribution as well as measures of quantum phase fluctuation and phase dispersion are obtained. The uniform phase distribution of the initial Fock states is observed to be transformed by the unitary operation (i.e., displacement operator) into non‐Gaussian shape, except for the initial vacuum state. It is observed that the phase distribution is symmetric with respect to the phase of the displacement parameter and becomes progressively narrower as its amplitude increases. The non‐unitary (photon addition/subtraction) operations make it even narrower in contrast to the Fock parameter, which leads to broadness. The photon subtraction is observed to be a more powerful quantum state engineering tool in comparison to the photon addition. Further, one of the quantum phase fluctuation parameters is found to reveal the existence of antibunching in both the engineered quantum states under consideration. Finally, the relevance of the engineered quantum states in the quantum phase estimation is also discussed. 相似文献