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101.
A. Fahli J. P. Coffin G. Guillaume B. Heusch F. Jundt F. Rami P. Wagner P. Fintz A. J. Cole S. Kox Y. Schutz N. Cindro 《Zeitschrift für Physik A Hadrons and Nuclei》1987,326(2):169-177
The light charged particles emitted in the40Ar+68Zn reaction performed at 14.6, 19.6 and 35 MeV/nucleon have been studied inclusively. The energy spectra have been analysed in terms of preequilibrium emission, moving source and coalescence models. A complete coherence between the present data and those obtained separately from heavy fragment studies is achieved. These data are consistent with the onset of projectile fragmentation between 20 and 35 MeV/nucleon correlated with the formation of a highly excited region of the nuclear system inducing light particle emission. The other sources of light particles can be interpreted as statistical and sequential decay of the quasi projectile. 相似文献
102.
Valentina A. Ol’shevskaya Rami Ayuob Pavel V. Petrovskii Galina L. Levit Valery N. Charushin Valery N. Kalinin 《Journal of organometallic chemistry》2005,690(11):2761-2765
General method for preparation of high yields of novel N-protected carborane amino acid derivatives, 3-acylamino-1-carboxymethyl-2-R-o-carboranes (R = H, Me, Ph), is reported. The synthesis starts from readily available 3-amino-o-carboranes and includes the protection of amino group, introduction of carboxymethyl function to the carbon atom of polyhedron via the metallation of carborane CH bond with sodium amide in liquid ammonia, and treatment of corresponding sodium carboranes with sodium bromoacetate. Deprotection of N-acylated carborane amino acids is studied in acidic media. Depending on the procedure employed, closo- or nido-carborane amino acids were obtained. 相似文献
103.
Copolymers of ethyl acrylate (M1) and n-butyl methacrylate (M2) were prepared by benzoyl peroxide initiation in solution at 60° and copolymer compositions estimated by [13C]-NMR spectroscopy. The kinetic behaviour is approximately ideal with r1 = 1/r2 = 0.47. Relaxation times T1 were determined for six of the carbons in M2 units and one in the M1 units; they range from 0.07 to 1.65 sec. 相似文献
104.
Rami Grossberg Monica VanDieren Andrés Villaveces 《Mathematical Logic Quarterly》2016,62(4-5):367-382
We prove the following main theorem: Let be an abstract elementary class satisfying the joint embedding and the amalgamation properties with no maximal models of cardinality μ. Let μ be a cardinal above the the Löwenheim‐Skolem number of the class. If is μ‐Galois‐stable, has no μ‐Vaughtian Pairs, does not have long splitting chains, and satisfies locality of splitting, then any two ‐limits over M, for , are isomorphic over M. 相似文献
105.
Bairavarasu SR Edwards ME Sastry MD Kochary F Kommidi P Reddy BR Lianos D Aggarwal MD 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(4):1581-1587
We present electron paramagnetic resonance (EPR)--evidence of photomagnetism under the conditions of in situ green laser illumination (photo-EPR) in lead magnesium niobate-lead titanate, Pb(Mg,Nb)O3-PbTiO3 (PMN-PT), containing nanoparticles/wires of orthorhombic beta-PbO as identified by Raman spectroscopy. Photo-EPR studies of the sample containing beta-PbO, brownish red in color, have shown intense line at g=2.00, and its yield increased when produced in the presence of 7.5 kG external magnetic field suggesting the formation of magnetic polaron. This was identified as due to interaction between Fe3+, photoinduced Pb3+ and unpaired electron trapped at oxygen vacancies. The photoinduced growth and decay of magnetic polaron has shown a non-exponential behavior. Photoluminescence (PL) studies were conducted with excitation at 308 nm (XeCl laser) and also at 454.5, 488 and 514.5 nm using Ar+ laser. The excitation with 308 nm gave broad PL centered at 500 and 710 nm the latter being quite prominent in beta-PbO containing crystals, along with cooperative luminescence at 350 nm involving two emitting centers. The excitation with Ar+ laser lines, close to the electronic absorption in samples containing beta-PbO gave richer and sharp PL emission in red region from the constituents of the magnetic polaron and also intense anti-Stokes emission on excitation with 514.5 nm radiation. This appears to be due to phototransfer optically stimulated luminescence (PT-OSL) involving electron-hole recombination at photoinduced magnetic polaron site. 相似文献
106.
Thomas TD Kukk E Sankari R Fukuzawa H Prümper G Ueda K Püttner R Harries J Tamenori Y Tanaka T Hoshino M Tanaka H 《The Journal of chemical physics》2008,128(14):144311
The carbon 1s photoelectron spectrum of CF4 measured at photon energies from 330 to 1500 eV shows significant contributions from nonsymmetric vibrational modes. These increase linearly as the photon energy increases. The excitation of these modes, which is not predicted in the usual Franck-Condon point of view, arises from the recoil momentum imparted to the carbon atom in the ionization process. A theory is presented for quantitative prediction of the recoil effect; the predictions of this theory are in agreement to the measurements. The experiments also yield the vibrational frequencies of the symmetric and asymmetric stretching modes in core-ionized CF4, the change in CF bond length upon ionization, -0.61 pm, and the Lorentzian linewidth of the carbon 1s hole, 67 meV. 相似文献
107.
S. Pitchumani C. Rami Reddy S. Rajadurai K.T. Joseph M. Santappa 《European Polymer Journal》1982,18(11):949-952
Solution blending of n-butyl methacrylate-ethyl acrylate copolymers with chlorinated rubber was investigated. The tensile properties of the blends were studied; it was concluded that the blends serve as good film forming materials. 相似文献
108.
New cationic palladium-bis(oxazoline)-phosphine (Pd-BOX-PR3) complexes (Pd-BOX-B and Pd-BOX-C) have been synthesized and characterized using 1H, 13C and 31P NMR, FTIR spectroscopy, and electrospray ionization mass spectrometry (ESI-MS). The new complexes were used as catalysts in the alkoxycarbonylation of alkynes with various alcohols as nucleophiles. The carbonylation has produced the gem-α,β-unsaturated ester isomer (3) in high regioselectivity and excellent yields. The catalyst systems have been optimized by screening the type of palladium complexes and also by varying the reaction parameters including the reaction time, solvent, and temperature. A mechanism of the catalytic cycle based on a N-protonated palladium bis(oxazoline) phosphine active species was proposed for the alkoxycarbonylation reaction. 相似文献
109.
110.
We have studied the influence of glycerol on the rheological behavior of viscoelastic surfactant solutions. The measurements
were carried out on the system CTAB and NaSal. This system shows two viscosity maxima with increasing NaSal concentration.
When water is replaced by glycerol, the viscosities and the structural relaxation times at the viscosity maxima decrease while
they increase at the viscosity minimum. As a result of the opposite changes the two maxima are replaced by a single maxima
when 40% water is replaced by glycerol. The change of the viscosities is a consequence of a change of the structural relaxation
times while the storage moduli remain constant. The opposite changes are a result of different mechanisms for the relaxation
times. At the maxima, the relaxation times are reptation controlled and depend on the intermicellar interaction energy. At
the minimum, relaxation times are kinetically controlled and depend on the intramolecular interaction. 相似文献