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41.
A silica-gel-supported heterogeneous phosphorus pentoxide reagent has been developed for the esterification of various long-chain carboxylic acids with aromatic alcohols. The reactions occurred under relatively mild conditions and afforded the desired products in good yields. All the compounds 3a—3x were screened for antibacterial and antifungal activity, which showed good activity against Gram positive and Gram negative bacteria and also good results against almost all fungal strains. The structures of the synthesized compounds were elucidated by IR, 1H NMR, 13C NMR, mass spectroscopic techniques and elemental analysis. 相似文献
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The paper deals with the influence of higher-order effects of dispersion on the femto-second transform limited pulse generation by compensating for linear chirp of self-phase modulation spectra in the dispersion-shifted fibers. It has been shown that the minimum propagation length with first-order dispersion term is 23 m, as reported earlier. If the higher-order dispersion effects are taken into consideration, this length is reduced to 11.5 m. With compensation of the first-order dispersion term, this length can be enhanced to 6.8161 × 103 km. This length can further be improved to 6.0343 × 109 km by compensation of first- and second-order dispersion terms together. The minimum pulse width and linewidth product without dispersion, with dispersion including higher-order dispersion effects, and with dispersion compensation, is found to be 0.44, 0.4418, and 0.4411, respectively. 相似文献
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SALAHUDDIN KHAN J JAYABALAN ASHA SINGH RAMA CHARI SUPARNA PAL S PORWAL T K SHARMA S M OAK 《Pramana》2014,82(2):359-364
We show that in a GaAs0.86P0.14/Al0.7Ga0.3As near-surface quantum well, there is coherent oscillation of holes observed in time-resolved reflectivity signal when the top barrier of the quantum well is sufficiently thin. The quantum well states interact with the surface states under the influence of the surface electric field. The time period of the observed oscillation is 120±10 fs. 相似文献
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Shoji IMAMICHI Mukesh Kumar SHARMA Radhika Pankaj KAMDAR Mikoto FUKUCHI Yoshihisa MATSUMOTO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2014,90(9):365-372
XRCC4 (X-ray cross-complementation group 4) is a protein associated with DNA ligase IV, which is thought to join two DNA ends at the final step of DNA double-strand break repair through non-homologous end-joining. It has been shown that, in response to irradiation or treatment with DNA damaging agents, XRCC4 undergoes phosphorylation, requiring DNA-PK. Here we explored possible role of ATM, which is structurally related to DNA-PK, in the regulation of XRCC4. The radiosensitizing effects of DNA-PK inhibitor and/or ATM inhibitor were dependent on XRCC4. DNA-PK inhibitor and ATM inhibitor did not affect the ionizing radiation-induced chromatin recruitment of XRCC4. Ionizing radiation-induced phosphorylation of XRCC4 in the chromatin-bound fraction was largely inhibited by DNA-PK inhibitor but further diminished by the combination with ATM inhibitor. The present results indicated that XRCC4 phosphorylation is mediated through ATM as well as DNA-PK, although DNA-PK plays the major role. We would propose a possible model that DNA-PK and ATM acts in parallel upstream of XRCC4, regulating through phosphorylation. 相似文献
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The Nie expression is amended in such a way that the expression follows the infinite pressure behaviour, i.e., \(P\to \infty \) or V → 0. A new empirical relationship is developed to predict the values of volume dependence of Grüneisen parameter. NaCl and ε-Fe have been employed to test the suitability of the expression. The results obtained reveal that the relationship is reliable as there is a good agreement between the calculated and the experimental data. 相似文献
47.
SADHANA MUKERJI H NAIK S V SURYANARAYANA S CHACHARA B S SHIVASHANKAR V MULIK RITA CRASTA SUDIPTA SAMANTA B K NAYAK A SAXENA S C SHARMA P V BHAGWAT K K RASHEED R N JINDAL S GANESAN A K MOHANTY A GOSWAMI P D KRISHNANI 《Pramana》2012,79(2):249-262
The 232Th(n, ??) reaction cross-section at average neutron energies of 13.5, 15.5 and 17.28?MeV from the 7Li(p, n) reaction has been determined for the first time using activation and off-line ??-ray spectrometric technique. The 232Th(n, 2n) cross-section at 17.28?MeV neutron energy has also been determined using the same technique. The experimentally determined 232Th(n, ??) and 232Th(n, 2n) reaction cross-sections from the present work were compared with the evaluated data of ENDF/BVII and JENDL-4.0 and were found to be in good agreement. The present data, along with literature data in a wide range of neutron energies, were interpreted in terms of competition between 232Th(n, ??), (n, f), (n, nf) and (n, xn) reaction channels. The 232Th(n, ??) and 232Th(n, 2n) reaction cross-sections were also calculated theoretically using the TALYS 1.2 computer code and were found to be in good agreement with the experimental data from the present work but were slightly higher than the literature data at lower neutron energies. 相似文献
48.
4- n -Nonyl-4-cyanobiphenyl, C22H27N, Mr= 305.45, triclinic, P 1, a=9.765(1)A, b= 11.460(2)A, c=17.860(2)A, alpha=85.460(2), beta=80.870(1), gamma=71.630(1) , V=1871.9(3)A3, Z= 4, Dm=1.079M g -3, Dc= 1.084 M g -3, mu=0.463 mm -1, F (000)=664, lambda (CuK alpha)=1.5418 A, final R and wR 2 are 0.0523 and 0.1559, respectively. 相似文献
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S. KUMAR V. SHARMA K. KISHOR 《应用数学和力学(英文版)》2013,34(4):501-522
Numerical and analytical investigations of the thermosolutal instability in a viscoelastic Rivlin-Ericksen fluid are carried out in the presence of a uniform vertical magnetic field to include the Hall current with a uniform angular velocity in a porous medium. For stationary convection, the stable solute gradient parameter and the rotation have stabilizing effects on the system, whereas the magnetic field and the medium permeability have stabilizing or destabilizing effects on the system under certain conditions. The Hall current in the presence of rotation has stabilizing effects for sufficiently large Taylor numbers, whereas in the absence of rotation, the Hall current always has destabilizing effects. These effects have also been shown graphically. The viscoelastic effects disappear for stationary convection. The stable solute parameter, the rotation, the medium permeability, the magnetic field parameter, the Hall current, and the vis-coelasticity introduce oscillatory modes into the system, which are non-existent in their absence. The sufficient conditions for the non-existence of overstability are also obtained. 相似文献