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101.
Reba Panigrahi Santosh Kumar Sahu Pradyota Kumar Behera Subhalaxmi Panda Prof. Laxmidhar Rout 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(3):620-624
CuII catalyst is less efficient at room temperature for C−S cross-coupling. C−S cross-coupling by CuII catalyst at room temperature is not reported; however, doping of copper with molybdenum metal has been realized here to be more efficient for C−S cross-coupling in comparison to general CuII catalyst. The doped catalyst CuMoO4 nanoparticle is found to be more efficient than copper. The catalyst works under mild conditions without any ligand at room temperature and is recyclable and effective for a wide range of thiols and haloarenes (ArI, ArBr, ArF) from milligram to gram scale. The copper-based bimetallic catalyst is developed and recognized for C−S cross-coupling of haloarenes with alkyl and aryl thiols. 相似文献
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Niranjan Panda Ashis Kumar JenaSasmita Mohapatra Smruti Ranjan Rout 《Tetrahedron letters》2011,52(16):1924-1927
The synergistic effects of iron and copper in copper ferrite nanoparticles for the N-arylation of heterocycles with aryl halides were demonstrated. The magnetic nature of the catalyst facilitates its removal from the reaction medium for further use. Negligible leaching of Cu and Fe in consecutive cycles makes the catalyst economical and environmentally benign for C-N cross-coupling reactions. 相似文献
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We have observed good ferroelectric loops at room temperature in hexagonal HoMnO3 (HMO) bulk ceramics sintered at 1250 °C. Microstructure and ferroelectric hysteresis loops are observed to be dependent on sintering temperature. It is observed that with an increase of sintering temperature, hexagonal a-axis is compressed and c-axis is marginally dilated with overall contraction of the hexagonal unit-cell volume. We explain the origin of ferroelectricity through relative movement of Ho ion and Mn ion within its unit-cell volume, resulting in the distortion of unit-cell volume. We argue that ferroelectric origin of hexagonal HMO at room temperature may be due to the marginal displacement of Ho ion along a-axis, that influences the exchange interaction among the Mn3+ and Ho3+ ions, causing magnetically induced ferroelectricity at room temperature. 相似文献
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The results of ab initio calculations of the pressure dependence of Fe magnetism in cubic FeGe are presented. We find that when the pressure-volume scale is set by means of generalized gradient approximation total energies and magnetism is described by means of the local density approximation, the critical pressure at which the magnetic phase transition occurs is estimated at ≈18 GPa, which is in good agreement with experiments. Using the disordered local moment method we find a localized to itinerant model cross-over of Fe magnetism in cubic FeGe, as a function of volume. Moreover, our calculations also suggest subtle signatures of longitudinal spin fluctuations in cubic FeGe, and that the stiffness parameter softens with increasing pressure. We associate the retention of metallicity in FeGe under pressure with the spin-disorder scattering. The effect of spin-orbit coupling on the electronic structure is also discussed. 相似文献
107.
Jahangir Mondal Amit K. Manna Kalyani Rout Sunil K. Singh Jnan P. Naskar 《International journal of environmental analytical chemistry》2013,93(12):1160-1174
ABSTRACTA new fluorescent-colorimetric chemosensor L has been synthesised by Schiff base condensation reaction between 1,8-diaminooctane and 4-nitro-benzaldehyde in very good yields. Its photo-luminescent properties and selective detection properties for hydrazine have been examined. The synthesised chemosensor exhibited highly selective fluorescence on-off response for hydrazine amongst a wide range of different metal cations, anions and amines, along with the bare eye colour change from colourless to yellow based on intermolecular hydrogen-bond interaction. The limit of detection of the chemosensor L was estimated as 9.77 × 10?8 M or 3.12 × 10?6 g L?1 for hydrazine which is extremely below the limit set by the World Health Organization (WHO) and the binding stoichiometry was proposed to be 1 : 2 based on 1H NMR spectroscopic techniques and the Job’s plot analysis. The proposed sensing mechanism is the hydrogen-bonding interaction which has further been established by Density Functional Theory (Functional Density Theory (DFT)) studies. This recognition feature of sensor L makes it an efficient chemosensor for hydrazine detection in different water samples. 相似文献
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