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71.
Sunil K. Singhal Veeresh Kumar K. Stalin Amit Choudhary Satish Teotia Gade B. Reddy Rakesh B. Mathur Surinder P. Singh Renu Pasricha 《Particle & Particle Systems Characterization》2013,30(5):445-452
Synergetic cooperation of individual components of the nanocomposites (NCs) is responsible for their novel properties that lead to various technological applications. A simple chemical process depicting the deposition of functionalized gold nanoparticles on the surface of boron nitride nanosheets (BNNSs) in solution is reported. The structure, chemical composition, and optical properties of nanosheets are systematically studied. The deposition of Au nanoparticles on BNNS (BNNSAu) results in plasmonic band modulation, thus altering the optoelectronic properties of BNNSs. The intense surface plasmon absorption band of BNNSAu is narrowed and red‐shifted relative to the absorption band of as synthesized monometallic BNNSs. The observations reflect the strong interfacial interaction between BNNS and Au nanoparticles. This approach constitutes a basis for a simple process leading to the preparation of functionalized BNNSs and their utilization as nanoscale templates for assembly and integration with other nanoscale materials for futuristic optoelectronic devices. 相似文献
72.
S.P. Purohit Anoop K. Jain K.C. Mathur 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,2(1):41-44
Within the framework of the rotating wave approximation the elastic scattering of electrons by metastable 2s state of hydrogen
atoms is studied in the presence of a resonant laser field. The frequency of the circularly polarized laser field is chosen
to match the 2s-3p transition frequency in the hydrogen atom. Variation of the cross section with laser intensity and with incident electron energy (50-150 eV) is investigated.
Received: 18 July 1997 / Received in final form: 5 December 1997 / Accepted: 19 January 1998 相似文献
73.
methodology for bremsstrahlung (BS) background correction to extract a true Compton profile in high-energy Compton scattering
experiments is presented. The BS background profiles for Hg, computed within the Born approximation, are estimated for different
values of incident energy. It is seen for the first time that the BS background contribution in high-energy Compton profile
experiments like those employing third generation synchrotron radiation sources comes out to be significant and non-linear.
Further, it is found that the incorporation of BS correction in data reduction of such an experiment performed on Hg at 662
keV energy helps in reconciliation of theory and experiment. 相似文献
74.
Matrix element of the Galilean invariant non-relativistic reduction of the pseudoscalar-pseudovector interaction has been
calculated assuming the reaction to be a direct process with boundπ
− being absorbed by a correlated pair of nucleons. The Hartree-Fock wavefunctions obtained with the unitary-model-operator
approach starting with the realistic nucleon-nucleon interaction have been used forπ-capturing nucleon pair in the initial state. The calculations have been done with and without antisymmetrising the initial
state wavefunction of the pion absorbing pair. For the final state nucleon-nucleon interaction has been taken into account.
The strongπ-nucleus interaction together with the Coulomb interaction with the finite nuclear size on the bound pion wavefunction are
taken into account. Angular distributions of the emitted nucleon-pair, the branching ratios and the total absorption rates
are calculated for16O with and without antisymmetrisation effect. The calculated results are compared with the experimental and other theoretical
work. 相似文献
75.
The conservation of channel spin implying that the spin of the initial bound pair coupled to that of the initial free particle
should result in the same channel spin as the spin of the final bound pair coupled to the spin of the final free particle,
follows as a consequence of three-body theory of transfer reactions with the assumption of separability of two-bodyt-matrix. To test the validity of this principle we look at the experimental data on stripping reactions on even-even nuclei.
We find that although reactions to channels not conforming to channel spin conservation are not altogether ruled out, the
cross-sections of reactions violating channel spin conservation are much smaller than those conforming to channel spin conservation. 相似文献
76.
77.
78.
N.S. Ramegowda M.N. Modi A.K. Koul J.M. Bora C.K. Narang N.K. Mathur 《Tetrahedron》1973,29(23):3985-3986
Synthesis of certain aldehydes from the carboxylic acids has been carried by reduction of the corresponding N-acyl saccharins using SDA. The N-acyl saccharins are easily prepared by reaction of an acid with γ-saccharin chloride, which can be used for the next step of reduction without isolation and purification. This provides a convenient and one step synthesis of aldehydes by combining the two reactions, viz., preparation of the N-acyl compound and its reduction. The method has been successfully applied for the reduction of aliphatic, alicyclic, aromatic, and a α,β-unsaturated acids to the corresponding aldehydes and the yields obtained are quite satisfactory. 相似文献
79.
80.
A potentiometric titration with alkye nitrite solutions is described for the determination of various sulpha, drugs. 相似文献