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11.
Belmesnaoui Aqzzouz Redouane Nouira 《Proceedings of the American Mathematical Society》2006,134(12):3515-3523
We give different necessary and sufficient conditions so that the space of AM-compact operators is an order ideal and we deduce some consequences. R´ESUME. Nous donnons différentes conditions nécessaires et suffisantes pour que l'espace des opérateurs AM-compacts soit un idéal d'ordre et nous déduisons quelques conséquences.
12.
X.L. Zhong 《Applied Surface Science》2006,253(2):417-420
Bi3.25La0.75Ti3O12 (BLT) thin films were fabricated on Pt/Ti/SiO2/Si(1 0 0) substrates by chemical solution deposition (CSD), and the dependence of ferroelectric and dielectric properties of the as-deposited BLT thin films on excess Bi content in precursor sols was studied. It is found that the prepared BLT thin film shows the best polarization-electric field, capacitance-voltage and dielectric constant (?r)-frequency characteristics, when the value of excess Bi content in precursor sols is 10%. In detail, its remnant polarization (2Pr) value is 40 μC/cm2, the capacitance tunability is 21% measured at room temperature under conditions of an applied voltage of 8 V and measurement frequency of 10 kHz, and the ?r is 696 at 100 kHz frequency. 相似文献
13.
Junko Kuwahara Hideo Akisada Tamaki Kato Norikazu Nishino 《Colloid and polymer science》2005,283(7):747-752
A series of peptides containing various hydrophobic amino acids [methionine (Met), leucine (Leu), norleucine (Nle), phenylalanine (Phe), 2-aminooctanoic acid (Aoc), and 2-aminodecanoic acid (Ade)] were synthesized and their conformations were studied using circular dichroism (CD) spectroscopy in different solvents such as water, methanol, and aqueous solution of ammonium tetradecanesulfonate. Peptides containing hydrophobic amino acids with linear side chains formed -sheets in water and methanol. Electrostatic interaction between the charged side chain (lysine) and a micelle consisting of an anionic surfactant, ammonium tetradecanesulfonate, is necessary for the formation of -helices in micellar environments. The conformational transition from -helix to -sheet structure required moderate hydrophobicity and linear side chains. This conformational transition depended on the surfactant concentration. 相似文献
14.
From the study of the CuCuBrCu2?εSC solid cell in the range of cubic digenite and “high temperature” hexagonal chalcocite we have deduced the laws of variation of the deviation from stoichiometry and the holes concentration with the equilibrium partial pressure of sulfur (δ and p are found to be proportional to ). The electronic model corresponding to the formation of associations (V×CuV′Cu) in the presence of neutral vacancies V×Cu allows one to explain these laws. In the low temperature range (range of “low temperature” hexagonal chalcocite and orthorhombic chalcocite) the study of thermal variations of Hall coefficient permits us to propose the following models: (a) the deviation from stoichiometry of the “low temperature” hexagonal chalcocite is due to the simple ionized vacancies V′Cu; (b) the deviation from stoichiometry of the orthorhombic chalcocite is due to the vacancies V′Cu and to the associations (V×CuV×Cu). 相似文献
15.
16.
R. S. Brusa M. Duarte Naia D. Margoni A. Zecca 《Applied Physics A: Materials Science & Processing》1995,60(5):447-453
We have determined the positron mobility (+) in polyethylene samples (67.2% crystalline, glass transition temperatureT
g=151 K) in the 64–400 K temperature range by Doppler shift measurements. A method based on the simulataneous observation of two lines from133Ba and137Cs radioactive sources together with the positron annihilation line, was employed to measure the Doppler shift of the 511 keV line as a function of the electric field applied to the samples. With this method we were able to measure at the same time the drift velocity of positrons and theS parameter. This parameter is very important in the interpretation of the mobility trend in samples where the positron states change with temperature. The positron mobility was corrected for positronium formation. + at 64 K is 31.7±0.8 cm2 V–1 s–1 then decreases up to 123 K, increases at 148 K and decreases again up to 170 K (+=26.9±0.8 cm2 V–s–). This sharp change in mobility is centred around the glass transition temperature of our samples. Then the mobility remains almost constant up to 230 K. From 250 K to 377 K, + increases and reaches the value of 38.4±1.0 cm2 V–1s–1. The corrected experimental data were well fitted by a simple model taking into account scattering and a thermally activated process (hopping mechanism). 相似文献
17.
S. Czajkowski M. Bernas P. Armbruster H. Geissel C. Kozhuharov G. Münzenberg D. Vieira Ph. Dessagne Ch. Miehe E. Hanelt G. Audi J. K. P. Lee 《Zeitschrift für Physik A Hadrons and Nuclei》1994,348(4):267-272
Neutron-rich Co and Fe isotopes produced by86Kr projectile fragmentation at 500 MeV/u were separated and identified using the fragment separator (FrS) in a bunched energy mode.66Co and65Fe ions were selectively implanted in a double PIN-diode array where the-decay signals were measured. The half-lives were deduced from time correlations between implantation and-decay signals. The remeasurement of the66Co half-life confirms the isotope identification. The value of the65Fe half-life was found to be 0.45±0.15 s. 相似文献
18.
Ferenc Mó ricz Ká roly Tandori 《Proceedings of the American Mathematical Society》1996,124(3):877-885
We study the a.e. convergence of orthogonal series defined over a general measure space. We give sufficient conditions which contain the Menshov-Rademacher theorem as an endpoint case. These conditions turn out to be necessary in the particular case where the measure space is the unit interval and the moduli of the coefficients form a nonincreasing sequence. We also prove a new version of the Menshov-Rademacher inequality.
19.
Luis A. Caffarelli Cristian E. Gutié rrez 《Transactions of the American Mathematical Society》1996,348(3):1075-1092
In this paper we consider a family of convex sets in , , , , satisfying certain axioms of affine invariance, and a Borel measure satisfying a doubling condition with respect to the family The axioms are modelled on the properties of the solutions of the real Monge-Ampère equation. The purpose of the paper is to show a variant of the Calderón-Zygmund decomposition in terms of the members of This is achieved by showing first a Besicovitch-type covering lemma for the family and then using the doubling property of the measure The decomposition is motivated by the study of the properties of the linearized Monge-Ampère equation. We show certain applications to maximal functions, and we prove a John and Nirenberg-type inequality for functions with bounded mean oscillation with respect to
20.
T. V. Panchapagesan 《Rendiconti del Circolo Matematico di Palermo》1993,42(2):219-248
A «CGS-property» for the spectral measures is introduced and the classical results of determining complete systems of unitary invariants for self-adjoint and bounded normal operators on separable Hilbert spaces are extended to the class of spectral measures with this property. As a consequence, the above mentioned results are extended to unbounded normal operators on separable Hilbert spaces. Moreover, three different kinds of multiplicity are defined and it is shown that for the measures with the «CGS-property» they all coincide. In the last section some analogues of the multiplicity functions defined by Stone [14] are related to the total multiplicity. 相似文献