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51.
Recent measurements of differential and elastic cross-sections, slope parameters and ratios of the real and imaginary parts
of the forward scattering amplitudes for pion-proton elastic scattering at 200 GeV/c have been fitted by using a simple Regge
pole model with phenomenological residue functions. The computed results for total cross-sections have also been compared
with the experimental data. 相似文献
52.
Spermidine, 1,3-diaminopropane, and p-phenylenediamine form molecular complexes with chloranil at pH 9. The composition and stability of these complexes have been studied spectrophotometrically. The results indicate that complexes were of 1:1 type and their stability increases with the basicities. The method of complexation was used to determine spectrophotometrically a ppm amount of SD, DAP, and PhDA in solution. The accuracy and precision of the method were found to be very high. 相似文献
53.
54.
The most recently measured differential cross-section data forπ
−
p → η’n has been fitted by using a simple Regge pole model with phenomenological residue functions. It has also been observed that
this inelastic process has the scaling property. 相似文献
55.
Saleem Ahmad Steven H. Spergel Joel C. Barrish John DiMarco Jack Gougoutas 《Tetrahedron: Asymmetry》1995,6(12):2893-2894
The absolute configuration of (+)-2,3,3-trimethyl-2-hydroxybutanoic acid, a key intermediate in the synthesis of the HIV-protease inhibitor 1a (isomer A), has been confirmed as (R) on the basis of X-ray analysis. 相似文献
56.
Jayasimhadri M Moorthy LR Saleem SA Ravikumar RV 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,64(4):939-944
Optical absorption, luminescence and lifetime measurements of Sm(3+)-doped alkali fluorophosphate glasses with molar compositions of 50(NaPO(3))(6)+10TeO(2)+20AlF(3)+19RF+1Sm(2)O(3) (R=Li, Na and K) are described. The variation of optical properties with glass composition plays a dominant role in the determination of efficient laser materials. From the experimental oscillator strengths of f-f electric dipole transitions, the phenomenological Judd-Ofelt parameters have been evaluated and are used to evaluate radiative parameters such as radiative transition probabilities (A(R)), branching ratios (beta(R)), lifetimes (tau(R)) and integrated absorption cross-section (sigma(a)) for various excited levels. The predicted values of tau(R) and beta(R) from the (4)G(5/2) excited level to its lower levels are compared with the experimentally measured values. Stimulated emission cross-sections (sigma(e)) were also determined for (4)G(5/2)-->(6)H(J) (J=5/2, 7/2, 9/2 and 11/2) emission transitions. From the emission transitions of Sm(3+) in these alkali tellurofluorophosphate glasses certain potential laser transitions have been identified. 相似文献
57.
Fahad Sultan Salah Hamodeh Yusuke Murayama Kadharbatcha S. Saleem Nikos Logothetis 《Magnetic resonance imaging》2010
Flattened representations are a useful approach to represent the convoluted complex surface of the neocortex of primates and other large-brained mammals. In this study, we compared the flattened representation of neocortical areas obtained from the recently published MRI and histology atlas of the rhesus monkey brain (Saleem KS, Logothetis NK. A combined MRI and histology atlas of the rhesus monkey brain in stereotaxic coordinates. London: Academic; 2007) with other previously published maps. Our results confirm that flat map representations are advantageous due to their ease of use and that current flat maps are well comparable to each other. Some differences arise due to different distinguishing criteria and here too flat maps can help to reveal them. 相似文献
58.
The soliton formation by the current-driven drift-like wave is investigated for heavier ion (such as barium) plasma experiments planned to be performed in future. It is pointed out that the sheared flow of electrons can give rise to short scale solitary structures in the presence of stationary heavier ions. The nonlinearity appears due to convective term in the parallel equation of motion and not because of temperature gradient unlike the case of low frequency usual drift wave soliton. This higher frequency drift-like wave requires sheared flow of electrons and not the density gradient to exist. 相似文献
59.
Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Tico JG Grauges E Lopez L Palano A Pappagallo M Eigen G Stugu B Sun L Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Pegna DL Lynch G Mir LM Orimoto TJ Osipenkov IL Ronan MT Tackmann K Tanabe T Wenzel WA Del Amo Sanchez P Hawkes CM Watson AT Koch H Schroeder T Walker D Asgeirsson DJ Cuhadar-Donszelmann T Fulsom BG Hearty C 《Physical review letters》2008,100(2):021801
We present measurements of the semileptonic decays B--->D0tau-nutau, B--->D*0tau-nutau, B0-->D+tau-nutau, and B0-->D*+tau-nutau, which are potentially sensitive to non-standard model amplitudes. The data sample comprises 232x10(6) Upsilon(4S)-->BB decays collected with the BABAR detector. From a combined fit to B- and B0 channels, we obtain the branching fractions B(B-->Dtau-nutau)=(0.86+/-0.24+/-0.11+/-0.06)% and B(B-->D*tau-nutau)=(1.62+/-0.31+/-0.10+/-0.05)% (normalized for the B0), where the uncertainties are statistical, systematic, and normalization-mode-related. 相似文献
60.
Nadia Sharif Faiza Saleem Farheen Aslam Shagufta Naz 《Natural product research》2015,29(20):1938-1941
Microalgae have been proposed as a promising source for biodiesel production. Focusing on algal strains for biodiesel production, efforts should be made to search new strains. Experiments were carried out to investigate the effects of growth parameters (nutrients, pH, light, aeration and temperature) and the oil percentage of eight algal strains (Chlorella sp., Cladophora sp., Hydrodictylium sp., Oedogonium sp., Oscillatoria sp., Spirogyra sp., Stigeocolonium sp., Ulothrix sp.). Results show that 6.5–7.5 is the optimum pH for the growth of all algal species. Temperature showed a greater variation (25°40°C). Ulothrix sp. gave more biomass productivity and is the most suitable strain for biodiesel production due to higher oil percentage (62%). Least biomass production was observed for Stigeocolonium sp. and least oil content was obtained from Hydrodictylium sp. It was observed that among these eight algal strains for biodiesel production, Ulothrix and Chlorella are the most promising algae species. 相似文献