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61.
62.
Singha Mousumi Pal Sangita Chowdhury Sujit Hareendran K. N. Sahu M. L. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(2):795-803
Journal of Radioanalytical and Nuclear Chemistry - The sorption capacity of an in–house synthesized novel resin Polyhydraxamic acid(PHA) towards Cu(II), Sr(II), Gd(III), U(VI) ions was... 相似文献
63.
Ritashree Pal Sean C. O'Brien Prof. Michael C. Willis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(51):11710-11714
We show that readily available α-amidoaldehydes are effective substrates for intermolecular Rh-catalyzed alkyne hydroacylation reactions. The catalyst [Rh(dppe)(C6H5F)][BArF4] provides good reactivity, and allows a broad range of aldehydes and alkynes to be used as substrates, delivering α-amidoketone products. High yields and high levels of regioselectivity are achieved. The use of α-amidoaldehydes as substrates establishes that 1,4-dicarbonyl motifs can be used as controlling groups in Rh-catalyzed hydroacylation reactions. 相似文献
64.
An efficient Pd‐catalyzed method for C—O cross‐coupling of ketoximes and chalcone oximes with activated aryl bromides and bromo‐chalcones has been developed. All oxime ethers were obtained in good to excellent yields by [(π‐allyl)PdCl]2/tBuXPhos ( L7 ) catalyst system. TrixiePhos ( L11 ) was also found to be effective for the oxime coupling. This method offers an easy and smooth coupling of chalcone oximes with activated aryl bromides and bromo‐chalcones, which has not been previously explored. 相似文献
65.
66.
We develop a variational theory for a dipolar condensate in an elongated(cigar shaped)confinement potential. Our formulation provides an effective one-dimensional extended meanfield theory for the ground state and its collective excitations. We apply our theory to investigate the properties of rotons in the system comparing the variational treatment to a full numerical solution. We consider the effect of quantum fluctuations on the scattering length at which the roton excitation softens to zero energy. 相似文献
67.
68.
In this paper, Mg-doped ZnO nanoparticles were synthesized by the facile sol–gel method. The crystalline structure, characteristic absorption bands and morphology of the obtained Mg-doped ZnO nanoparticles were studied by XRD, FTIR and TEM. The thermal degradation behaviour of the samples was investigated by differential scanning calorimetry (DSC) and thermogravimetry (TG). The effect of Mg concentrations and annealing temperatures on the antibacterial properties of the obtained nanoparticles was investigated in detail. The results indicated that doping Mg ions into ZnO lattice could enhance its antibacterial activity. Antibacterial assay demonstrated that Mg-doped ZnO with 7% Mg content annealed at 400 °C had the strongest antibacterial activity against Listeria monocytogenes (98.7%). This study indicated that the inhibition rate of ZnO nanoparticles increased with the formation of granular structure and the decrease of ZnO size due to the doping of Mg ions into the ZnO lattice. 相似文献
69.
Niedermaier O Scheit H Bildstein V Boie H Fitting J von Hahn R Köck F Lauer M Pal UK Podlech H Repnow R Schwalm D Alvarez C Ames F Bollen G Emhofer S Habs D Kester O Lutter R Rudolph K Pasini M Thirolf PG Wolf BH Eberth J Gersch G Hess H Reiter P Thelen O Warr N Weisshaar D Aksouh F Van den Bergh P Van Duppen P Huyse M Ivanov O Mayet P Van de Walle J Aystö J Butler PA Cederkäll J Delahaye P Fynbo HO Fraile LM Forstner O Franchoo S Köster U Nilsson T Oinonen M Sieber T Wenander F Pantea M 《Physical review letters》2005,94(17):172501
We report on the first radioactive beam experiment performed at the recently commissioned REX-ISOLDE facility at CERN in conjunction with the highly efficient gamma spectrometer MINIBALL. Using 30Mg ions accelerated to an energy of 2.25 MeV/u together with a thin (nat)Ni target, Coulomb excitation of the first excited 2+ states of the projectile and target nuclei well below the Coulomb barrier was observed. From the measured relative deexcitation gamma-ray yields the B(E2;0(+)gs-->2(+)1) value of 30Mg was determined to be 241(31)e2 fm4. Our result is lower than values obtained at projectile fragmentation facilities using the intermediate-energy Coulomb excitation method, and confirms the theoretical conjecture that the neutron-rich magnesium isotope 30Mg resides outside the "island of inversion." 相似文献
70.
K.V. Prasad Dulal Pal V. Umesh N.S. Prasanna Rao 《Communications in Nonlinear Science & Numerical Simulation》2010,15(2):331-344
An analysis has been carried out to study the momentum and heat transfer characteristics in an incompressible electrically conducting non-Newtonian boundary layer flow of a viscoelastic fluid over a stretching sheet. The partial differential equations governing the flow and heat transfer characteristics are converted into highly non-linear coupled ordinary differential equations by similarity transformations. The effect of variable fluid viscosity, Magnetic parameter, Prandtl number, variable thermal conductivity, heat source/sink parameter and thermal radiation parameter are analyzed for velocity, temperature fields, and wall temperature gradient. The resultant coupled highly non-linear ordinary differential equations are solved numerically by employing a shooting technique with fourth order Runge–Kutta integration scheme. The fluid viscosity and thermal conductivity, respectively, assumed to vary as an inverse and linear function of temperature. The analysis reveals that the wall temperature profile decreases significantly due to increase in magnetic field parameter. Further, it is noticed that the skin friction of the sheet decreases due to increase in the Magnetic parameter of the flow characteristics. 相似文献