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81.
Fabrice Domingues Dos Santos Pascale Fabre Xavier Drujon Gilles Meunier Ludwik Leibler 《Journal of Polymer Science.Polymer Physics》2000,38(23):2989-3000
Structured latexes provide a promising route to hard coatings without the use of coalescing aids. We studied the thermomechanical properties of films from structured soft‐core/hard‐shell hydrophobic latexes. We found that the mechanical properties of these films were closely related to their very particular organization. When the rigid phase was continuous, whatever its volume fraction, the films exhibited a high elastic modulus. An analysis of the viscoelastic properties of the films provided a good method for obtaining information about the interphase between the hard shell and soft core of the latex particles. By varying the film structure through annealing or the particle composition (core/shell ratio, core crosslinking, etc.), we were able to tune the mechanical properties of the films. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 2989–3000, 2000 相似文献
82.
83.
Pascale De Meuter Jo Amelrijckx Hubert Rahier Bruno Van Mele 《Journal of Polymer Science.Polymer Physics》1999,37(20):2881-2892
The slow isothermal crystallization of concentrated amorphous starch systems is measured by Modulated Differential Scanning Calorimetry (MDSC). It can be followed continuously by the evolution (stepwise decrease) of the MDSC heat capacity signal (Cp), as confirmed with data from X-ray diffractometry, Dynamic Mechanical Analysis, Raman spectroscopy, and conventional Differential Scanning Calorimetry. Isothermal MDSC measurements enable a systematic study of the slow crystallization process of a concentrated starch system, such as a pregelatinized waxy corn starch with 24 wt % water and 76 wt % starch. After isothermal crystallization, a broad melting endotherm with a bimodal distribution is observed, starting about 10°C beyond the crystallization temperature. The bulk glass transition temperature (Tg) decreases about 15°C during crystallization. The isothermal crystallization rate goes through a maximum as a function of crystallization time. The maximum rate is characterized by the time at the local extreme in the derivative of Cp (tmax), or by the time to reach half the decrease in Cp (t1/2). Both tmax and t1/2 show a bell-shaped curve as a function of crystallization temperature. The temperature of maximum crystallization rate, for the system studied, lies as high as 75°C. This is approximately 65°C above the initial value of Tg. Normalized Cp curves indicate the temperature dependence of the starch crystallization mechanism. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2881–2892, 1999 相似文献
84.
Alain Bekaert Pascale Lemoine Jean Daniel Brion Bernard Viossat 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):m76-m77
The title compound, tris[(R)‐2‐hydroxypropanamide‐κ2O,O′]zinc(II) tetrabromozincate, [Zn(C3H7NO2)3][ZnBr4], contains one monomeric six‐coordinate zinc complex cation and one tetrahedral [ZnBr4]2− anion. Both ZnII atoms lie on threefold axes. Coordination in the cation occurs via the amide and hydroxy O atoms [Zn—O = 2.074 (5) and 2.073 (6) Å] and has a distorted octahedral geometry, with cis‐O—Zn—O angles in the range 76.2 (2)–109.2 (2)°. In the crystal structure, the cations and anions are linked by N—H⋯Br and O—H⋯O hydrogen bonds, generating a three‐dimensional network. 相似文献
85.
Silu Wang Johan Jacquemin Pascale Husson Christopher Hardacre Margarida F. Costa Gomes 《The Journal of chemical thermodynamics》2009,41(11):1206-1214
The volumetric properties of seven {water + ionic liquid} binary mixtures have been studied as a function of temperature from (293 to 343) K. The phase behaviour of the systems was first investigated using a nephelometric method and excess molar volumes were calculated from densities measured using an Anton Paar densimeter and fitted using a Redlich–Kister type equation. Two ionic liquids fully miscible with water (1-butyl-3-methylimidazolium tetrafluoroborate ([C1C4Im][BF4]) and 1-ethyl-3-methylimidazolium ethylsulfate ([C1C2Im][EtSO4])) and five ionic liquids only partially miscible with water (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C1C2Im][NTf2]), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C1C4Im][NTf2]), 1-butyl-3-methylimidazolium hexafluorophosphate ([C1C4Im][PF6]), 1-butyl-3-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([C1C4Pyrro][NTf2]), and butyltrimethylammonium bis(trifluoromethylsulfonyl)imide ([N4111][NTf2])) were chosen. Small excess volumes (less than 0.5 cm3 · mol?1 at 298 K) are obtained compared with the molar volumes of the pure components (less than 0.3% of the molar volume of the pure ionic liquid). For all the considered systems, except for {[C1C2Im][EtSO4] + water}, positive excess molar volumes were calculated. Finally, an increase of the non-ideality character is observed for all the systems as temperature increases. 相似文献
86.
87.
Alarcón SH Palleschi G Compagnone D Pascale M Visconti A Barna-Vetró I 《Talanta》2006,69(4):1031-1037
Competitive electrochemical enzyme-linked immunosorbent assays based on disposable screen-printed electrodes have been developed for quantitative determination of ochratoxin A (OTA). The assays were carried out using monoclonal antibodies in the direct and indirect format. OTA working range, I50 and detection limits were 0.05-2.5 and 0.1-7.5 μg L−1, 0.35 (±0.04) μg L−1 and 0.9 (±0.1) μg L−1, 60 and 100 μg L−1 in the direct and indirect assay format, respectively. The immunosensor in the direct format was selected for the determination of OTA in wheat. Samples were extracted with aqueous acetonitrile and the extract analyzed directly by the assay without clean-up. The I50 in real samples was 0.2 μg L−1 corresponding to 1.6 μg/kg in the wheat sample with a detection limit of 0.4 μg/kg (calculated as blank signal −3σ). Within- and between-assay variability were less than 5 and 10%, respectively. A good correlation (r = 0.9992) was found by comparative analysis of naturally contaminated wheat samples using this assay and an HPLC/immunoaffinity clean-up method based on the AOAC Official Method 2000.03 for the determination of OTA in barley. 相似文献
88.
Marie Labat Jean-Blaise Brubach Alessandra Ciavardini Marie-Emmanuelle Couprie Erik Elkaim Pierre Fertey Tom Ferte Philippe Hollander Nicolas Hubert Emmanuelle Jal Claire Laulhé Jan Luning Olivier Marcouillé Thierry Moreno Paul Morin Francois Polack Pascale Prigent Sylvain Ravy Jean-Paul Ricaud Pascale Roy Mathieu Silly Fausto Sirotti Amina Taleb Marie-Agnès Tordeux Amor Nadji 《Journal of synchrotron radiation》2018,25(2):385-398
The investigation of ultrafast dynamics, taking place on the few to sub‐picosecond time scale, is today a very active research area pursued in a variety of scientific domains. With the recent advent of X‐ray free‐electron lasers (XFELs), providing very intense X‐ray pulses of duration as short as a few femtoseconds, this research field has gained further momentum. As a consequence, the demand for access strongly exceeds the capacity of the very few XFEL facilities existing worldwide. This situation motivates the development of alternative sub‐picosecond pulsed X‐ray sources among which femtoslicing facilities at synchrotron radiation storage rings are standing out due to their tunability over an extended photon energy range and their high stability. Following the success of the femtoslicing installations at ALS, BESSY‐II, SLS and UVSOR, SOLEIL decided to implement a femtoslicing facility. Several challenges were faced, including operation at the highest electron beam energy ever, and achievement of slice separation exclusively with the natural dispersion function of the storage ring. SOLEIL's setup also enables, for the first time, delivering sub‐picosecond pulses simultaneously to several beamlines. This last feature enlarges the experimental capabilities of the facility, which covers the soft and hard X‐ray photon energy range. In this paper, the commissioning of this original femtoslicing facility is reported. Furthermore, it is shown that the slicing‐induced THz signal can be used to derive a quantitative estimate for the degree of energy exchange between the femtosecond infrared laser pulse and the circulating electron bunch. 相似文献
89.
90.
Jessie Casimiro Bénédicte Lepoittevin Caroline Boisse-Laporte Marie-Geneviève Barthés-Labrousse Pascale Jegou Fran?ois Brisset Philippe Roger 《Plasma Chemistry and Plasma Processing》2012,32(2):305-323
With the aim of introducing primary amino groups on the surface of poly(ethylene terephthalate) (PET), two methods were compared—the
use of ammonia or a combination of nitrogen and hydrogen low-pressure microwave plasma. Several plasma parameters were optimized
on the reactor to increase the –NH2 surface density, which was estimated by colorimetric titration and X-ray photoelectron spectroscopy (XPS). These techniques
show that whatever the plasma treatment, almost 2 –NH2/nm2 are incorporated on PET films. Emission spectroscopy highlighted a correlation between the density of primary amino groups
and the ratio between an NH peak intensity and an Ar peak intensity (INH/IAr). Variation in surface hydrophilicity with aging in air after plasma treatment was monitored with contact angle measurements
and showed a hydrophobic recovery. This was confirmed by XPS, which suggests also that surfaces treated by NH3 plasma are more stable than surfaces treated by N2/H2. 相似文献