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101.
Agustin Campos Rafael Gavara Roberto Tejero Clara Gomez Bernardo Celda 《Journal of Polymer Science.Polymer Physics》1989,27(8):1559-1597
The Flory–Huggins theory as modified by Pouchlý has been applied to calculate preferential (λ) and total (Y) sorption coefficients for a ternary polymer system. The ternary interaction function (?1?2?3GT(u1, ?3)) is described as the product of three independent binary functions. This expression allows prediction of λ and Y from binary interaction parameters χ, χ, g, g, and g12(?10). Three ternary polymer systems are used to check the validity of the expression. Moreover for polymer systems in which the parameters g and/or g are unknown, a procedure to evaluate them has been developed and verified on systems for which sufficient experimental information is available. 相似文献
102.
Elvio A. Campos Yoshitaka Gushikem Maria do Carmo Gonçalves Sandra C. de Castro 《Journal of colloid and interface science》1996,180(2):453
The Nb2O5/cellulose composite was prepared by reacting α-cellulose with NbCl5-n(OC2H5)n, in nonaqueous solvent, under nitrogen atmosphere and submitting the obtained material to hydrolysis. An increase in the crystallinity degree is observed in the composite material because the precursor reagent reacts with the amorphous phase of the cellulose fibers. Loadings between 4.5 and 16.0% of the oxide were achieved and in every case the oxide particles uniformly cover the fiber surface. Lewis and Brønsted acid sites were determined by using pyridine as the basic molecular probe. 相似文献
103.
104.
Esmail Ahouzi Katarzyna Chalasinska-Macukow Juan Campos Maria J. Yzuel 《Optical Review》1996,3(3):177-183
Pure phase correlation with improved discrimination capability is proposed. The improvement is achieved by designing a region of support based on the discrimination capability (DC). We propose four approaches for designing this region; some of them consider the input scene in the design, while others are input scene invariant. The performances of these approaches are compared by numerical simulation. The DC is improved significantly for the multi-object scenes even when using an input scene invariant region of support design. 相似文献
105.
A. Delgado J. Campos C. Sánchez del Río 《Zeitschrift für Physik A Hadrons and Nuclei》1972,257(1):9-13
The lifetimes of eight levels belonging to the 6p configuration of KrI and thirteen levels belonging to different configurations of KrII have been measured. The levels were excited by short electron pulses of appropriate energy and the lifetimes determined by a delayed coincidence method using single photon counting techniques. All measurements were carried out at different gas pressures. The measured lifetimes of the KrII levels are compared with other experimental results obtained by a different method (beam-foil spectroscopy) and with calculations made in the intermediate coupling scheme. 相似文献
106.
In this work the deexcitation of the B3Π+(Ou+), v′ = 14 level of I2 after pulsed laser excitation has been studied. The quenching cross sections by collisions with I2, H2, CO, and CH4 have been measured. The experimental results are 190 ± 14, 2.5 ± 0.3, 15.1 ± 0.4, and 18.0 ± 0.6 Å2, respectively. These values are compatible (within 30%) with the semiempirical scaling law of proportionality with the product of polarizability and the square root of reduced mass. 相似文献
107.
The radiative lifetimes of the and states of CO2+ were measured by means of the delayed coincidence method. Excitation was performed by a pulsed electron beam incident on CO2. The results of these measurements are 115 ± 5 nsec for the state and 126 ± 3 nsec for the state. 相似文献
108.
The shape transition in the Zr isotopes is investigated in the framework of the Shell Model. The neutron-proton interaction between selected orbitals is found to be instrumental for the onset of deformation in this neutron-rich region. 相似文献
109.
110.