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1.
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
2.
Tripti Vimal Shivani Pandey Swadesh K. Gupta Dharmendra P. Singh Kaushlendra Agrahari Govind Pathak 《Liquid crystals》2018,45(5):687-697
Rod-shaped 5 wt.% copper-doped ZnO (ZnO:Cu2+) ferromagnetic nanoparticles (NPs), prepared by hydrothermal method, were dispersed in ferroelectric liquid crystal (FLC) named Felix 17/100. The effect of ferromagnetic NPs on the physical properties of FLC material (Felix 17/100) has been investigated by dielectric, electro-optical and polarising optical microscopic methods. A noteworthy time-dependent memory has been observed in the NPs-dispersed FLC composite attributed to the coupling of magnetic field associated to NPs with the director orientation of FLC. Improvement in spontaneous polarisation and dielectric susceptibility of FLC material has been ensued with the addition of ferromagnetic NPs. Faster electro-optic response, at lower applied voltage, has also been observed in NPs-dispersed FLC composite. These changes are accredited to the magneto-electric dipolar coupling existing due to the interactions between magnetic-dipole and electric-dipole moments of magnetic NPs and FLC material, respectively. The formation of periodic domains capable to show memory effect has been observed in composite. The observed time-dependent memory was confirmed by dielectric and electro-optical methods. FLC material enriched with the properties of ferromagnetic NPs can be utilised in advanced multifunctional optical devices, time-dependent memory-based security devices and computational purposes. 相似文献
3.
Munish Puri Shivani Gupta Parveen Pahuja Aneet Kaur J. R. Kanwar J. F. Kennedy 《Applied biochemistry and biotechnology》2010,160(1):98-108
β-D-galactosidase (EC 3.2.1.23) from Kluyveromyces marxianus YW-1, an isolate from whey, has been studied in terms of cell disruption to liberate the useful enzyme. The enzyme produced
in a bioreactor on a wheat bran medium has been successfully immobilized with a view to developing a commercially usable technology
for lactose hydrolysis in the food industry. Three chemical and three physical methods of cell disruption were tested and
a method of grinding with river sand was found to give highest enzyme activity (720 U). The enzyme was covalently immobilized
on gelatin. Immobilized enzyme had optimum pH and temperature of 7.0 and 40 °C, respectively and was found to give 49% hydrolysis
of lactose in milk after 4 h of incubation. The immobilized enzyme was used for eight hydrolysis batches without appreciable
loss in activity. The retention of high catalytic activity compared with the losses experienced with several previously reported
immobilized versions of the enzyme is significant. The method of immobilization is simple, effective, and can be used for
the immobilization of other enzymes. 相似文献
4.
Ramdas S. Pathare Shivani Sharma Kandasamy Gopal Devesh M. Sawant Ram T. Pardasani 《Tetrahedron letters》2017,58(14):1387-1389
An efficient one-pot protocol for the synthesis of multi-substituted 2-pyrone derivatives from internal alkynes and unactivated alkenes is reported. The methodology involves difunctionalization of internal alkynes by using Pd(II) as a catalyst alongwith X-Phos as ligand via 6-endo transesterification and subsequent alkenylation pathway. Notable features include simple and easily available starting materials, including a range of unactivated alkenes, reduced synthetic steps and mild reaction conditions with high efficiency. 相似文献
5.
6.
K.K. Bhasin Neelam Singh Shivani R.J. Butcher 《Journal of organometallic chemistry》2006,691(4):621-628
A large number of α-naphthyl selenium and tellurium compounds (1-14) have been prepared through two different methods. The first method involves the alkylation of sodium 1-naphthylselenolate/tellurolate, generated in situ using hydrazine hydrate as reducing agent while the second method involves the reaction of in situ generated α-naphthylseleno/telluromagnesium bromide with an appropriate electrophile. The synthesized alkyl-1-naphthyl selenides/tellurides and some α,ω-bis(1-naphthylseleno)alkanes have been characterized with the help of elemental analysis and using various spectroscopic techniques viz., NMR (1H, 13C, 77Se and 125Te), IR, UV/vis spectroscopy and mass spectrometry (only in few representative cases). Interpretation of 1H, 13C NMR spectra and assignment of individual resonances for tris(1-naphthylseleno)methane have been done with the help of [1H-1H] and [1H-13C] correlation spectroscopy (COSY). X-ray crystallographic results and molecular geometry of benzyl-1-naphthyl selenide, 2 and diphenylmethyl-1-naphthyl selenide, 3 have also been illustrated. 相似文献
7.
Synthesis of N-succinimidyl-(S)-2-(6-methoxynaphth-2-yl) propionate was carried out by the reaction of (S)-naproxen with N-hydroxysuccinimide in the presence of dicyclohexyl carbodiimide. It was characterized and was used as a chiral derivatizing reagent, under mild conditions, to form diastereomers of dl-penicillamine which were resolved by reversed-phase high-performance liquid chromatography using triethyl ammonium phosphate buffer (pH 4.0, 5mM)-acetonitrile (linear gradient (30min) of acetonitrile from 30 to 70%). Excellent separation was achieved with gradient mobile phase. The detection limit was at pmol level. 相似文献
8.
Atenolol and propranolol (the β-blocking agents) and salbutamol (broncho- and vasodilator) were resolved into their enantiomers by adopting different modes of loading/impregnating the Cu(II) complexes of l-proline (l-Pro), l-phenylalanine (l-Phe), l-histidine (l-His), N,N-dimethyl-l-phenylalanine (N,N-Me2-l-Phe), and l-tryptophan (l-Trp) on commercial precoated normal phase plates. The three different approaches were (A) using the Cu(II)-l-amino acid complex as chiral mobile phase additive, (B) ascending development of plain commercial plates in the solutions of Cu complex, and (C) using a solution of Cu(II) acetate as mobile phase additive for the commercial TLC plates impregnated with ascending development of plates in the solutions of amino acid. Spots were located using iodine vapour. The results obtained for the three methods have been compared for their efficiency and the issue of involvement of the Cu(II) cation for the best performance of the three methods has been discussed with respect to the same mobile phase. The detection limit is 0.18 μg for each enantiomer. 相似文献
9.
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
10.
Novel achiral and chiral alkyl alpha-(1,3-benzothiazol-2-ylsulfonyl)-alpha-fluoroacetates can be readily synthesized by metalation-fluorination of (1,3-benzothiazol-2-ylsulfonyl)acetates. DBU-mediated condensations of these fluorinated synthons with aldehydes proceed in a facile manner at 0 degrees C or at room temperature giving high yields of alpha-fluoro acrylates. Ketones are unreactive under these conditions. The presence of fluorine renders the synthon substantially more reactive compared to the unfluorinated analogue. Reactivity of alpha-(1,3-benzothiazol-2-ylsulfonyl)-alpha-fluoroacetate and the Horner-Wadsworth-Emmons reagent (EtO)2P(O)CHFCOOEt has also been compared. 相似文献