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1.
2.
J‐F. Masson Slaana Bundalo‐Perc Ana Delgado 《Journal of Polymer Science.Polymer Physics》2005,43(3):276-279
Differential scanning calorimetry (DSC) does not allow for easy determination of the glass‐transition temperature (Tg) of the polystyrene (PS) block in styrene–butadiene–styrene (SBS) block copolymers. Modulated DSC (MDSC), which deconvolutes the standard DSC signal into reversing and nonreversing signals, was used to determine the (Tg) of both the polybutadiene (PB) and PS blocks in SBS. The Tg of the PB block was sharp, at ?92 °C, but that for the PS blocks was extremely broad, from ?60 to 125 °C with a maximum at 68 °C because of blending with PB. PS blocks were found only to exist in a mixed PS–PB phase. This concurred with the results from dynamic mechanical analysis. Annealing did not allow for a segregation of the PS blocks into a pure phase, but allowed for the segregation of the mixed phase into two mixed phases, one that was PB‐rich and the other that was PS‐rich. It is concluded that three phases coexist in SBS: PB, PB‐rich, and PS‐rich phases. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 276–279, 2005 相似文献
3.
Given a vector measure ν with values in a Banach space X, we consider the space L1(ν) of real functions which are integrable with respect to ν. We prove that every order continuous Banach function space Y continuously contained in L1(ν) is generated via a certain positive map related to ν and defined on X* x M, where X* is the dual space of X and M the space of measurable functions. This procedure provides a way of defining Orlicz spaces with respect to the vector measure ν. 相似文献
4.
Tomás Chacón Rebollo Antonio Domı́nguez Delgado Enrique D. Fernández Nieto 《Comptes Rendus Mathematique》2004,338(1):85-90
In this work we introduce a class of balanced numerical schemes, up to second order, for the solution of general non-homogeneous hyperbolic systems of conservation laws. We give a general technique to build such schemes. We also prove that they balance up to second order a large class of steady solutions in the whole domain but some subset whose measure tends to zero as the grid size decreases to zero. We finally present an application to Shallow Water equations that exhibit the good performances of some of the schemes introduced. To cite this article: T. Chacón Rebollo et al., C. R. Acad. Sci. Paris, Ser. I 338 (2004). 相似文献
5.
We study extension of operators T: E→ L0([0, 1]), where E is an F–function space and L0([0, 1]) the space of measurable functions with the topology of convergence in measure, to domains larger than E, and we study the properties of such domains. The main tool is the integration of scalar functions with respect to stochastic
measures and the corresponding spaces of integrable functions.
Partially supported by D.G.I. #MTM2006-13000-C03-01 (Spain). 相似文献
6.
J. C. Delgado J. Andreu G. Sardin J. Esteve J. L. Morenza 《Applied Physics A: Materials Science & Processing》1988,46(3):207-213
Films of a-Si: H have been deposited by means of a dc hot cathode discharge of SiH4 with electrostatic confinement at a pressure as low as 0.4 Pa. The plasma used is quite quiescent as has been observed by means of reproducible Langmuir probe measurements. Substrates have been placed at different locations in between the electrodes, some of them facing the anode and the others facing the cathode.Films deposited on substrates facing the cathode present a granular, non-columnar, structure, an IR spectrum with only SiH absorption peaks, and a very low photoresponse. Films deposited on substrates facing the anode have a similar IR spectrum but are homogeneous, have lower hydrogen content, and present a high photoresponse. The optical absorption coefficient shows in all samples thenE=C(E–E0)
x
behaviour, but with exponentx=3 and notx=2 as is usually considered in a-SiH. 相似文献
7.
A parametric study of sandwich-type discharge chamber nitrogen lasers has been carried out. A non-monotonic dependence of the energy emitted by the laser and the discharge chamber thickness is found. Discharge chambers with = 1 have the best electro-optical efficiency. The ratio between the electrode gap,d, and is found to be a scaling parameter. The possible influence of wall ablation in the comportment is also discussed. 相似文献
8.
A semi-continuous dilatometer for measuring excess volume is described. Excess volumes of p-xylene +n-hexane + n-octane, +n-decane, +n-dodecane, +n-tetradecane, and +n-hexadecane have been measured at 298.15 K as a function of composition. 相似文献
9.
Summary The general objective is to provide an alternative methodology based on capillary electrophoresis (CE) to characterize flavonoids from honey and hence determine its botanical origin. The specific objective is to compare the separation of flavonoids by CE with those achieved by HPLC to assess CE as an alternative technique for the determination of honey flavonoids. Fourteen different flavonoids isolated from honey were analysed by MECC and compared to the HPLC separations. It was difficult to find specific experimental conditions to separate all the flavonoids from honey in a single MEKC run. Three chromatographic conditions are optimized and, depending on the flavonoid markers sought in honey, the appropriate detection method should be chosen. Compared to the HPLC results, it is clear that CE could be an alternative technique in honey flavonoids analysis and particularly in the study of its geographical and floral origin. 相似文献
10.
Graciela Díaz de Delgado Ramírez V. Belkis Miguel Delgado José Rosquete P. Carmelo 《Journal of chemical crystallography》1995,25(7):371-374
The title compound, formula C15H20O2, is orthorhombic, P212121 witha=8.747(2),b=12.025(3),c=12.554(3)Å,Z=4, andD
m
=1.32(2)g/ml. The structural analysis shows that the compound corresponds to eudesma-4(15),7(11)-dien-8,12-olide, a sesquiterpene lactone previously isolated fromAster umbellatus but whose crystal structure was unknown. 相似文献