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31.
32.
An efficient synthesis of 5‐arylidine‐2,4‐thiazolidinediones has been developed using dicationic ionic liquid as green medium and catalyst. This method performed well for the condensation of both aryl as well as heteryl aldehydes with 2,4‐thiazolidinedione and gave 5‐arylidine‐2,4‐thiazolidinediones with excellent yields. 相似文献
33.
Rudra P. Sarkar 《Proceedings Mathematical Sciences》2008,118(2):255-272
We shall investigate the use of Abel transform on PSL2(ℝ) as a tool beyond K-biinvariant setup, discuss its properties and show some applications. 相似文献
34.
C. Raghu Indranil Rudra Diptiman Sen S. Ramasesha 《Journal of Chemical Sciences》2001,113(5-6):459-486
One of the fascinating fields of study in magnetism in recent years has been the study of quantum phenomena in nanosystems.
While semiconductor structures have provided paradigms of nanosystems from the stand point of electronic phenomena, the synthesis
of high nuclearity transition metal complexes have provided examples of nano magnets. The range and diversity of the properties
exhibited by these systems rivals its electronic counterparts. Qualitative understanding of these phenomena requires only
a knowledge of basic physics, but quantitative study throws up many challenges that are similar to those encountered in the
study of correlated electronic systems. In this article, a brief overview of the current trends in this area are highlighted
and some of the efforts of our group in developing a quantitative understanding of this field are outlined. 相似文献
35.
An electron gas in crossed electric and magnetic fields of arbitrary strength is considered in the framework of nonequilibrium
statistical mechanics. It is known that more than one independent frequency existing in a system, which are of comparable
magnitude, can generate coherent synergic radiation. In the present system three independent frequencies exist: viz the synchrotron
frequency due to the magnetic field, the hopping frequency due to the electric field, and the plasma frequency. It is shown
that all these can combine to generate a new synergic coherent radiation. The results also show the possibility of interpreting
the quantum nature of Hall conductance as due to density function alone. Besides these, the solution admits the Schubnikov-de
Haas oscillation of the electrical conductivity due to change in the fields. 相似文献
36.
37.
Jyoti Bhawan Singh Shakti Pratap Gupta Mohit Tripathi Sudhanshu Verma Alok Kumar Singh Devraj Yadav R. R. 《Acoustical Physics》2021,67(6):584-589
Acoustical Physics - We have estimated elastic, mechanical, thermal and ultrasonic properties, in high temperature regime, of cobalt nanowires (Co-NWs) having a hexagonal close-packed (HCP)... 相似文献
38.
J.S. Yadav B.V. Subba Reddy Ashutosh Pratap Singh Nilanjan Majumder 《Tetrahedron letters》2010,51(17):2291-4626
Morita-Baylis-Hillman acetates undergo smooth allylic nucleophilic substitution (SN2′) with tosylmethyl isocyanide (TosMIC) in the presence of a catalytic amount of BF3·OEt2 under mild conditions to furnish trisubstituted olefins in high yields with (E)-stereoselectivity. 相似文献
39.
Manish Pratap Singh Rajendra Kumar Singh Dr. Suresh Chandra Prof. 《Chemphyschem》2010,11(9):2036-2043
Porous silica matrices of different pore sizes with confined ionic liquid (1‐butyl‐3‐methylimidazolium hexafluorophosphate) [BMIM] [PF6] were prepared by sol‐gel technique using a tetraethyl orthosilicate (TEOS) precursor with an aim to study the changes in physico‐chemical properties of ionic liquid on confinement. It is found that on confinement 1) melting point decreases, 2) fluorescence spectra shows a red shift and 3) the vibrational bands are affected particularly those of imadazolium ring, which interacts more with the walls of the silica matrix. Preliminary theoretical calculations suggest that SiO2 matrix interact more with the heterocyclic group of [BMIM] cation than the tail alkyl chain end group resulting in significant changes in the aromatic vibrations. 相似文献
40.
A simple, rapid, and solvent-free method for quantitative determination of benzene, toluene, and Xylene in exposed Drosophila larvae was developed using headspace solid-phase microextraction (HS-SPME) coupled to GC/MS. Larvae fed on standard Drosophila food mixed with benzene, toluene, and Xylene for 48 h were homogenized in Milli-Q water. Extraction of benzene, toluene, and Xylene was performed at 65 degrees C for 30 min on the SPME fiber (silica-fused). Subsequently, the fiber was desorbed in the GC injection port, followed by GC/MS analysis in the selected-ion monitoring mode. An external calibration curve was used for the quantification of benzene, toluene, and Xylene in the exposed organism. Recoveries were in the range of 78-82% (intraday) and 76-81% (interday) in larvae, and 91-96% (intraday) and 87-92% (interday) in the diet. LOD with an S/N of 3:1 and LOQ with an S/N of 10:1 were in the range of 0.01-0.023 and 0.034-0.077 microg/L, respectively. Percent RSD values for benzene, toluene, and Xylene were in the range of 0.50-0.81 (intraday) and 0.89-1.23 (interday) for retention time, and 2.16--3.85 (intraday) and 2.99-4.95 (interday) for peak concentration, showing good repeatability. This method was sensitive enough to quantitate benzene, toluene, and Xylene in small exposed organisms like Drosophila larvae. The SPME/GC/MS method developed may have wider applications in various in vivo toxicological studies. 相似文献