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41.
It is shown that a vorticity, constructed from the spin field of a quantum spinning plasma, combines with the classical generalized vorticity (representing the magnetic and the velocity fields) to yield a new grand generalized vorticity that obeys the standard vortex dynamics. Expressions for the quantum or spin vorticity and for the resulting generalized helicity invariant are derived. Reduction of the rather complex spinning quantum system to a well known and highly investigated classical form opens familiar channels for the delineation of physics peculiar to dense plasmas spanning solid state to astrophysical objects. A simple example is worked out to show that the magnetics of a spinning plasma can be much richer than that of the corresponding classical system. 相似文献
42.
We consider a parametrization of the lepton mixing matrix in which the deviations from maximal atmospheric mixing and vanishing reactor mixing are obtained in terms of small corrections from the charged lepton sector. Relatively large deviations for the reactor mixing angle from zero as indicated by T2K experiment can be obtained in this parametrization. We are able to further reduce the number of complex phases, thus, simplifying the analysis. In addition, we have obtained the sides of unitarity triangles and the vacuum oscillation probabilities in this parametrization. The Jarlskog rephasing invariant measure of CP violation at the leading order has a single phase difference which can be identified as Dirac-type CP violating phase in this parametrization. 相似文献
43.
New series of phenylantimony chloride and antimony chloride with Schiff base ligands, L1H and L2H having N∩S and N∩O donor systems were synthesized under microwave irradiation using a domestic microwave oven. The reaction time was brought down from hours to a few seconds with improved yield as compared with conventional heating. All the ligands and their antimony(III) derivatives were characterized on the basis of microanalysis, elemental analyses, molecular weight determinations and spectral studies including IR, NMR (1H and 13C) and electronic spectral studies. A distorted trigonal bipyramidal and pseudo‐octahedral geometry around the antimony atom was tentatively proposed for these derivatives. The compounds were screened in vitro against bacteria and fungi to test their antimicrobial property and in vivo in male albino rats to test their antifertility properties. The treatment with the ligands and their phenylantimony derivatives at dose levels of 20 mg per rat per day did not cause any significant change in body weight, but a significant reduction in the weights of reproductive organs was observed. Arrest of spermatogenesis was noted at various stages with production of primary spermatocytes (preleptotene and pachytene), secondary spermatocytes and step‐19 spermatids found to be decreased. Biochemical parameters of tissues, i.e. protein, sialic acid, cholesterol content of testes and seminal vesicular fructose also showed significant reduction. Further, the serum testosterone concentrations were also decreased after treatment with ligands and their antimony(III) derivatives. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
44.
S. Mahajan W. Ito C. H. Cho T. Morishita 《Physica C: Superconductivity and its Applications》1994,220(3-4):227-232
We report on the fabrication and characteristics of sandwich-type tunnel junctions with highly crystalline sputtered a-axis oriented thin film of Y1Ba2Cu3O7-x (YBC) as the base and the counter electrode. The junctions have been fabricated on SrTiO3 (100) and MgO (100) substrates. A non-superconducting phase of YBC corresponding to a lattice constant of 4.08 Å is used as the barrier layer making this an all YBC sandwich junction. For all temperatures below Tce (R=0) of the device, a zero voltage current was observed. The critical current density (Jc) of the device was found to be dependent on the thickness of the barrier layer and the crystallinity of the a-axis oriented YBC electrodes. At 40 K, such a junction fabricated on a SrTiO3 (100) substrate was found to have a Jc of 1.8 X 104 A/cm2 and an IcRn product of 0.2 mV. 相似文献
45.
R. M. Sawant M. A. Mahajan D. J. Shah U. K. Thakur K. L. Ramakumar 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(2):423-426
A rapid method for simultaneous determination of fluorine and chlorine in radioactive liquid wastes with ion chromatography
after pyrohydrolysis separation was proposed for routine analysis. The elements were separated from radioactive liquid wastes
by pyrohydrolysis and were subsequently determined with ion chromatograpy. Total time taken to determine these elements is
about 45 min including 30 min for the pyrohydrolysis and 15 min for ion chromatography. The results of recovery tests ranged
95% or above. The limits of detection for F and Cl are 0.5 and 0.8 mg kg−1, respectively. 相似文献
46.
Sonu Kumar Rajveer Singh Debrupa Dutta Shivani Chandel Arka Bhattacharya Velayutham Ravichandiran Soumi Sukla 《Molecules (Basel, Switzerland)》2022,27(23)
Natural products are being targeted as alternative anticancer agents due to their non-toxic and safe nature. The present study was conducted to explore the in vitro anticancer potential of Justicia adhatoda (J. adhatoda) leaf extract. The methanolic leaf extract was prepared, and the phytochemicals and antioxidant potential were determined by LCMS analysis and DPPH radical scavenging assay, respectively. A docking study performed with five major alkaloidal phytoconstituents showed that they had a good binding affinity towards the active site of NF-κB. Cell viability assay was carried out in five different cell lines, and the extract exhibited the highest cytotoxicity in MCF-7, a breast cancer cell line. Extract-treated cells showed a significant increase in nitric oxide and reactive oxygen species production. Cell cycle analysis showed an arrest in cell growth at the Sub-G0 phase. The extract successfully inhibited cell migration and colony formation and altered mitochondrial membrane potential. The activities of superoxide dismutase and glutathione were also found to decrease in a dose-dependent manner. The percentage of apoptotic cells was found to increase in a dose-dependent manner in MCF-7 cells. The expressions of caspase-3, Bax, and cleaved-PARP were increased in extract-treated cells. An increase in the expression of NF-κB was found in the cytoplasm in extract-treated cells. J. adhatoda leaf extract showed a potential anticancer effect in MCF-7 cells. 相似文献
47.
48.
L. D. Mahajan 《Colloid and polymer science》1934,69(1):16-21
Ohne Zusammenfassung
übersetzt von H. Erbring (Leipzig). 相似文献
49.
50.