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1.
The aim of this work was to investigate the physical and mechanical performance of architectural polyester (PES)–poly(vinyl chloride) (PVC) membranes exposed to different artificial aging conditions. Two commercially available architectural membranes were chosen as research objects. The durability of the PES/PVC fabrics was evaluated by the loss in mechanical performance, scanning electron microscopy, and X-ray diffraction analysis in order to understand the effect of the degradation agents on the surface of the membranes. The mechanical performance of the PES/PVC membranes was unchanged. Scanning electron microscopy images of the tested materials showed initial cracks after aging. The X-ray fluorescence analysis showed that at the time of aging, the amount of Cl and Si decreased slightly, while Ti decreased by half, and Ca by volume increased twice. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47523.  相似文献   
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This article examines the relationships between the employment suburbanisation from central cities towards their suburbs, and the process of intra-urban specialisation that occurred simultaneously in the fifty largest French metropolitan areas. A methodology is proposed to identify urban subcentres and to analyse the effects of the intra-urban specialisations on suburbanisation patterns. We conclude that the specialisation of both subcentres and central cities has a significant effect on suburbanisation rates. Lastly, an intra-metropolitan shift/share analysis provides additional insights into the employment dynamics of central cities and suburbs during the last twenty years. Received: 25 July 2000 / Accepted: 29 May 2001  相似文献   
4.
We propose an on-line learning algorithm for Multi Layered Perceptrons (MLP) with an Orthogonal Weight Estimator (OWE) architecture. Such an architecture allows to dynamically and efficiently estimate the weights of a MLP in context dependent behaviour problems. The proposed learning algorithm attempts to solve the problem of time-consuming in the learning phase encountered to train these weight estimators.  相似文献   
5.
In this paper, four different physical treatments (microwaves, heating by conduction, sonication and pressure autoclaving) were performed to degrade a pure DNA extract, and their influence on GMO quantification was studied. The aim was to check the hypothesis that processing of agrofood products results in a similar degradation rate for both the transgenic target and the specific target. Indeed we could observe that even if the used physical treatments could lead to a significant increase of C t values for both transgenic and specific targets, the resulting ΔC t remained stable. So, the main conclusion of the study is that the aforementioned hypothesis seems valid and thus a physical degradation of DNA will not affect the relative quantitation of the GMO content, provided that both the specific and transgenic targets have very similar size. A second important issue of the experiments performed was that DNA is a very robust molecule as it is extremely difficult to reach a mean size below 100 bp. The study also gives evidence of the importance of using small targets.  相似文献   
6.
A microstructural and mechanical analysis was performed on three rapidly solidified nickel base superalloys. Transmission and scanning electron microscopy along with tensile tests were performed on the ribbons in the as-cast and aged condition. This investigation permitted a correlation to be made between cooling rate, microstructure, and mechanical properties. It was found that melt spinning significantly altered the physical characteristics of the alloys studied. The rapid cooling rates (∼107 K/s) produced ribbons with a low dislocation density and small (∼1 μm) low angle cells. The precipitation of γ′ was suppressed, producing alloys with a smaller volume fraction of precipitates and lower APBE than in the conventionally cast condition. Also, the matrix/precipitate lattice mismatch was higher in the melt spun foils. Tensile strengths were similar to those in the conventional form; however, no measurable ductility was present. Aging the ribbons resulted in increases in γ′ volume fraction, tensile strengths, APBE, and elongations compared to the as-cast ribbons. The results of this work suggest that many of the microstructural refinements produced by melt spinning are lost after a short aging time at moderate temperatures.  相似文献   
7.
The processing costs involved in regional accent normalization were evaluated by measuring differences in lexical decision latencies for targets placed at the end of sentences with different French regional accents. Over a series of 6 experiments, the authors examined the time course of comprehension disruption by manipulating the duration and presentation conditions of accented speech. Taken together, the findings of these experiments indicate that regional accent normalization involves a short-term adjustment mechanism that develops as a certain amount of accented signal is available, resulting in a temporary perturbation in speech processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Structural, mean- and individual-level, differential, and ipsative personality continuity were examined in 599 patients treated for major depression assigned to 1 of 6 forms of a 6-month pharmaco-psychotherapy program. Covariation among traits from the Five Factor model remained invariant across treatment, and patients described themselves as slightly more extraverted, open to experience, agreeable and conscientious, and substantially more emotional stable after treatment. Trait changes were only to a small extent explained by changes in depression severity. There was evidence for differential, individual-level, and ipsative stability, with stable personality profiles in terms of shape and to a lesser extent in terms of scatter and elevation. Traits remain relatively stable, except for emotional stability, despite the depressive state and the psychopharmacological interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Summary Systems of poly(ethylene oxide)/polystyrene and of poly(ethylene oxide)/poly(styrene-co-acrylic acid) of different ratios were studied by inverse gas chromatography using benzene and n-decane as molecule probes and by viscosimetry in tetrahydrofuran. The transition temperatures as shown in the retention diagrams and the interaction parameters as determined by inverse gas chromatography and by viscosimetry showed that whereas poly(ethylene oxide) is incompatible with polystyrene, the introduction of amounts of acrylic acid groups into polystyrene chains by free radical copolymerization led to compatible systems of the acidic copolymer with the poly(ethylene oxide).  相似文献   
10.
Eighty-seven pet dogs (Canis familiaris) were involved in an experiment in which they had to solve a task to obtain a ball. After witnessing a full demonstration by their owner (10 times pushing the handle of the box, which released a ball), most dogs preferred to touch the handle sooner and more frequently in comparison with other parts of the box, and they used the handle to get the ball. In contrast dogs in 3 control groups developed their own respective methods. The lack of emergence of the ball and playing after the demonstration did not affect the learning performance strongly. This suggests that in dogs the outcome of a demonstration plays only a restricted role in the manifestation of social learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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