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151.
152.
E. Duek L. Kowalski M. Rajagopalan J. M. Alexander T. W. Debiak D. Logan M. Kaplan M. Zisman Y. LeBeyec 《Zeitschrift für Physik A Hadrons and Nuclei》1982,307(3):237-245
Measurements are reported for correlated energies and angles of heavy fragments from reactions of 343 MeV40Ar with197Au. The results show a continuous evolution of the mass distributions from fission-like products at angle pairs of ≈60 and 300 degrees to deeply inelastic projectile-like products at ≈45° and 300°. Certain difficulties are emphasized for the use of the “symmetric fragmentation” cross sections in the context of current theoretical models (e.g. the “extra push” theory). The fission-like reactions have been studied in some detail and the results have been compared to a Monte Carlo kinematic simulation. To account for the experimental results forward-peaked light particle emission (n, H, He) must occur in a large fraction of the fission-like reactions. 相似文献
153.
Bharathibai J. Basu D. K. Padma S. R. Rajagopalan 《Fresenius' Journal of Analytical Chemistry》1994,349(6):477-478
Trace of iron(III) are determined by differential pulse polarography in a medium of sodium hydroxide and sodium bromate using the catalytic current. Various cations do not interfere. The relative standard deviation is 2%. 相似文献
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Dronavajjala KD Rajagopalan R Uppili S Sen A Allara DL Foley HC 《Journal of the American Chemical Society》2006,128(40):13040-13041
A simple approach is described here for the in-place synthesis of polymer brushes by surface-initiated polymerization. A cyano-terminated self-assembled monolayer on a gold surface was used to anchor a highly active cationic Pd organometallic initiator by ligand exchange. We grew ultrasmooth patterned poly(4-methoxystyrene) brushes with excellent thickness control at room temperature. 相似文献
159.
Weiss V Thiruvengadathan R Regev O 《Langmuir : the ACS journal of surfaces and colloids》2006,22(3):854-856
We present a detailed study on the integration of individual single-walled carbon nanotubes (SWNTs) within a lyotropic hexagonal liquid crystal (LC) for the first time. Two systems are studied in this work; in the first, the same surfactant is used for both the dispersion of the SWNTs and the formation of the LC. In the second system, we use different surfactants for the dispersion of SWNTs and LC formation. Light microscopy imaging combined with small-angle X-ray scattering (SAXS) indicates that the nanotubes (NTs) are well dispersed and aligned along the LC director. The macroscopic property, namely, the viscosity, is strongly enhanced by the presence of the NTs. 相似文献
160.
S. Munawar Basha S. Ramasubramanian R. Thangavel M. Rajagopalan J. Kumar 《Journal of magnetism and magnetic materials》2010,322(2):238-241
Investigations have been carried out to study the ferromagnetic properties of transition metal (TM) doped wurtzite GaN from first principle calculations using tight binding linear muffin-tin orbital (TBLMTO) method within the density functional theory. The present calculation reveals ferromagnetism in nickel doped GaN with a magnetic moment of 1.13 μB for 6.25% of Ni doping and 1.32 μB for 12.5% of nickel doping, there is a decrease of magnetic moment when two Ni atoms are bonded via nitrogen atom. The Ga vacancy (VGa) induced defect shows ferromagnetic state. Here the magnetic moment arises due to the tetrahedral bonding of three N atoms with the vacancy which is at a distance of 3.689 Å and the other N atom which is at a distance of 3.678 Å .On the other hand the defect induced by N vacancy (VN) has no effect on magnetic moment and the system shows metallic character. When Ni is introduced into a Ga vacancy (VGa) site, charge transfer occur from the Ni ‘d’ like band to acceptor level of VGa and formed a strong Ni–N bond. In this Ni–VGa complex with an Ni ion and a Ga defect, the magnetic moment due to N atom is 0.299 μB .In case of Ni substitution in Ga site with N vacancy, the system is ferromagnetic with a magnetic moment of 1 μB. 相似文献