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31.
Subbarayan Velusamy 《Tetrahedron letters》2006,47(6):923-926
Copper(II) complex 1 selectively catalyzes the oxidation of primary alcohols to aldehydes in high yields by atmospheric oxygen in the presence of TEMPO. This procedure does not require an additive and the catalyst 1 is recyclable without loss of activity. 相似文献
32.
Ramu Rajasekaran Prakasarao Aruna Dornadula Koteeswaran Munusamy Baludavid Singaravelu Ganesan 《Journal of fluorescence》2014,24(4):1199-1205
Urine is one of the diagnostically potential bio fluids, as it contains many metabolites and some of them are native fluorophores. These fluorophores distribution and the physiochemical properties may vary during any metabolic change or at different pathologic conditions. Since urine is a multicomponent fluid, synchronous luminescence technique, a powerful tool has been adopted to analyse multicomponents in single spectrum and to resolve emission spectrum without much of photobleaching of fluorophores. In this study, urine samples of both normal subjects and cancer patients were characterised using synchronous luminescence spectroscopy with a Stokes shift of 20 nm. Different ratio parameters were calculated from the intensity values of the synchronous luminescence spectra and they were used as input variables for a multiple linear discriminant analysis across normal and cancer groups. The stepwise linear discriminant analysis classifies 90.3 % of the original grouped cases and 88.6 % of the cross-validated grouped cases correctly. 相似文献
33.
Anniyev T Kaya S Rajasekaran S Ogasawara H Nordlund D Nilsson A 《Angewandte Chemie (International ed. in English)》2012,51(31):7724-7728
Scratching beneath the surface: Pt-M(3d)-Pt(111) (M(3d) = Co, Ni) bimetallic subsurface alloys have been designed to show the ligand effect tunes reactivity in oxygen and hydrogen adsorption systems. The platinum-oxygen bond order was investigated by oxygen atom projection in the occupied and unoccupied space using X-ray emission spectroscopy (XES) and X-ray absorption spectroscopy (XAS). 相似文献
34.
Rajapandiyan Krishnamoorthy Jegan Athinarayanan Vaiyapuri Subbarayan Periyasamy Mohammad A. Alshuniaber Ghedeir Alshammari Mohammed Jamal Hakeem Mohammed Asif Ahmed Ali A. Alshatwi 《Molecules (Basel, Switzerland)》2022,27(8)
The increase in β-lactam-resistant Gram-negative bacteria is a severe recurrent problem in the food industry for both producers and consumers. The development of nanotechnology and nanomaterial applications has transformed many features in food science. The antibacterial activity of zinc oxide nanoparticles (ZnO NPs) and their mechanism of action on β-lactam-resistant Gram-negative food pathogens, such as Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Serratia marcescens, Klebsiella pneumoniae, and Proteus mirabilis, are investigated in the present paper. The study results demonstrate that ZnO NPs possesses broad-spectrum action against these β-lactamase-producing strains. The minimal inhibitory and minimal bactericidal concentrations vary from 0.04 to 0.08 and 0.12 to 0.24 mg/mL, respectively. The ZnO NPs elevate the level of reactive oxygen species (ROS) and malondialdehyde in the bacterial cells as membrane lipid peroxidation. It has been confirmed from the transmission electron microscopy image of the treated bacterial cells that ZnO NPs diminish the permeable membrane, denature the intracellular proteins, cause DNA damage, and cause membrane leakage. Based on these findings, the action of ZnO NPs has been attributed to the fact that broad-spectrum antibacterial action against β-lactam-resistant Gram-negative food pathogens is mediated by Zn2+ ion-induced oxidative stress, actions via lipid peroxidation and membrane damage, subsequently resulting in depletion, leading to β-lactamase enzyme inhibition, intracellular protein inactivation, DNA damage, and eventually cell death. Based on the findings of the present study, ZnO NPs can be recommended as potent broad-spectrum antibacterial agents against β-lactam-resistant Gram-negative pathogenic strains. 相似文献
35.
The hot rotating compound systems formed in heavy ion collisions are studied using the statistical theory with a view to determine
the spin and temperature dependence of nuclear shapes. Shape transitions are observed for these systems at particular spin
values. The neutron and proton separation energies for heavier high spin systems have been evaluated. Results are presented
for
70
170
Yb and
78
194
Pt. 相似文献
36.
Subbarayan Velusamy 《Tetrahedron letters》2004,45(25):4917-4920
The acetalization of aldehydes has been studied with methanol, ethanol, and 2-propanol using CoCl2 in high yields under reflux conditions. The reaction is simple, efficient, chemoselective and does not involve any other additive. 相似文献
37.
Colour SU(3) symmetry is broken spontaneously by the introduction of coloured Higgs scalars in the standard SU(3)×SU(2)×U(1)
model, so as to make the quarks integrally charged. The resulting couplings of the Higgs bosons with the gauge bosons are
worked out. 相似文献
38.
Nucleon emission from high spin fused compound systems is analyzed in the framework of the statistical theory of hot rotating
(STHR) nuclei. This is an elaborate version of our earlier work and we present our results for156Er,166Er,168 Yb and188Hg. We predict an increase in neutron emission for166Er due to the abrupt decrease in neutron separation energy aroundI ≈55ℏ. Since the drop in the separation energy is closely associated with the structural changes in the rotating nuclei, relative
increase in neutron emission probability around certain values of angular momentum may be construed as evidence for the shape
transition. A similar effect is predicted for168Yb aroundI ≈55ℏ. We also extend the microscopic cranked Nilsson method (CNM) to hot nuclear systems and compare the results with that of the
STHR method. The two methods yield different results for triaxially deformed nuclei although for biaxial deformations the
results are identical. This is illustrated for186Hg. 相似文献
39.
We formulate a theory of generalized Fock spaces which underlies the different forms of quantum statistics such as ‘infinite’,
Bose-Einstein and Fermi-Dirac statistics. Single-indexed systems as well as multi-indexed systems that cannot be mapped into
single-indexed systems are studied. Our theory is based on a three-tiered structure consisting of Fock space, statistics and
algebra. This general formalism not only unifies the various forms of statistics and algebras, but also allows us to construct
many new forms of quantum statistics as well as many algebras of creation and destruction operators. Some of these are: new
algebras for infinite statistics,q-statistics and its many avatars, a consistent algebra for fractional statistics, null statistics or statistics of frozen
order, ‘doubly-infinite’ statistics, many representations of orthostatistics, Hubbard statistics and its variations. 相似文献
40.
Neutrino-mass textures proposed at high scales are known to be unstable against radiative corrections especially for nearly
degenerate mass eigenvalues. We find a mechanism in a class of gauge models including 2HDM where the RG constraints can be
evaded. Consequently, a high-scale texture can match the low-energy data or be reproduced at low energies. 相似文献