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741.
M. F. Mahmood 《Optical and Quantum Electronics》1998,30(3):175-179
A new model of the non-linear propagation of optical solitons with initial linear frequency chirp through lossy highly birefringent fibres, allowing the improvement of the practical results concerning the distortionless signal transmission in ultra-high-speed communications, is presented within the framework of a system of coupled non-linear Schrödinger (CNLS) equations. This model demonstrates the existence of bound chirped solitons in a lossy single-mode highly briefringent fibre. 相似文献
742.
743.
The X-ray crystallographic molecular dimensions and thermal response of the 5, 13-diphenyl-cyclonoa [b]naphthalene 1a , are described. 相似文献
744.
745.
Cronin-Hennessy D Lyon AL Thorndike EH Savinov V Coan TE Fadeyev V Gao YS Maravin Y Narsky I Stroynowski R Ye J Wlodek T Artuso M Ayad R Boulahouache C Bukin K Dambasuren E Karamov S Majumder G Moneti GC Mountain R Schuh S Skwarnicki T Stone S Wang JC Wolf A Wu J Kopp S Kostin M Mahmood AH Csorna SE Danko I McLean KW Xu Z Godang R Bonvicini G Cinabro D Dubrovin M McGee S Zhou GJ Lipeles E Pappas SP Schmidtler M Shapiro A Sun WM Weinstein AJ Würthwein F Jaffe DE Masek G Paar HP Potter EM Prell S 《Physical review letters》2001,86(17):3730-3734
The CLEO experiment at the CESR collider has used 13.7 fb(-1) of data to search for the production of the Omega(0)(c) (css ground state) in e(+)e(-) collisions at square root of (s) approximately 10.6 GeV. The modes used to study the Omega(0)(c) are Omega(-)pi(+), Omega(-)pi(+)pi(0), Xi-K-pi(+)pi(+), Xi0K-pi(+), and Omega(-)pi(+)pi(+)pi(-). We observe a signal of 40.4+/-9.0(stat) events at a mass of 2694.6+/-2.6(stat)+/-1.9(syst) MeV/c(2), for all modes combined. 相似文献
746.
Shamsipur M Yeganeh-Faal A Chaichi MJ Tajbakhsh M Parach A 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,66(3):546-551
The chemiluminescence arising from the reaction of bis(2,4,6-trichlorophenyl)oxalate (TCPO) with hydrogen peroxide in the presence of brightener 4,4'-bis{[4,6-bis(2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino}stilbene-2,2'-disulfonic acid-disodium salt (Triazinyl) has been studied. The influence of concentration of TCPO, hydrogen peroxide, Triazinyl, base catalysts and temperature on the resulting chemiluminescence was investigated. The kinetic parameters for the peroxyoxalate-chemiluminescence (PO-CL) of Triazinyl were evaluated from computer fitting of the resulting intensity-time plots. The activation energies, E(a), were evaluated from temperature dependence of the corresponding rise and fall rate constants. 相似文献
747.
748.
Zaharudin?AhmadEmail author Zal?U’yun?Wan Mahmood Hidayah?Shahar Mei?Wo?Yii Ahmad?Sanadi?Abu Bakar 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(1):329-334
Large volumes of surface seawater samples were collected from thirty locations in the Exclusive Economic Zone (EEZ) of the
east coast Peninsular Malaysia on June 2008 to study the activity concentrations of 137Cs. The results will serve as additional information to the existing baseline data and is very useful for monitoring fresh
input of anthropogenic radionuclide into Malaysian marine environment. In this study, the activity concentrations of 137Cs were determined using co-precipitation technique, followed by Gamma Spectrometry measurement. The mean activity concentration
of 137Cs ranged between 3.40 and 5.89 Bq/m3. Higher activity concentrations were observed at the coastal and towards the south of Peninsular Malaysia and were aligned
with the high turbidity. These may due to the rapid diffusion of 137Cs from suspended particulates and fine sediments into surface seawater. The activity concentrations of 137Cs observed in this study were slightly higher than the concentrations reported in seawater at the Straits of Malacca, Vietnam
and Philippines. This might be because the study area received more input of 137Cs that originated from global fallout and then deposited on land which later being transported subsequently into the coastal
zone due to siltation and erosion processes. It could also be attributed to the intrusion of river waters containing higher
concentrations of 137Cs. 相似文献
749.
An efficient solvent free method for the synthesis of various 3,4-dihydropyrimidin-2(1H)-one/thiones in excellent yields using sulfonatedβ-cyclodextrine as recyclable catalyst is described.Sulfonatedβ-cyclodextrine was found to be efficient,recyclable heterogeneous catalyst and showed rate enhancements,high yields and short reaction times in this transformation. 相似文献
750.
A new mode of transport is described that was capable of high-resolution separation of superparamagnetic materials from complex mixtures based on their size. Laminar flow and a rotating external magnetic field were applied to superparamagnetic beads assembled on a semiperiodic micromagnet array. Beads at the edge of the micromagnet array oscillated in-phase with the external magnetic field with an amplitude that decreased with increasing frequency, ω, until they reached an immobilization frequency, ω(i), where the beads stopped moving. Laminar flow along the edge of the array could be tuned to sweep the beads for which ω < ω(i) downstream at a velocity that increased with size while leaving beads for which ω > ω(i) undisturbed. Flow-enhanced nonlinear magnetophoresis (F-NLM) promises to enable multiple superparamagnetc bead types to be used in the fractionation of cells and implementation of diagnostic assays. 相似文献