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排序方式: 共有6895条查询结果,搜索用时 15 毫秒
1.
Virginija Sacevičienė Milda Jucienė Vaida Dobilaitė Valentina Krylova Skirma Žalenkienė Nijolė Dukštienė Raimondas Bliūdžius 《应用聚合物科学杂志》2019,136(21):47523
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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Indoor surfaces may be adsorptive sinks with the potential to change Indoor Air Quality. To estimate this effect, the sorption parameters of formaldehyde and toluene were assessed on five floorings by an experimental method using solid-phase microextraction in an airtight emission cell. Adsorption rate constants ranged from 0.003 to 0.075 m·h−1, desorption rate constants from 0.019 to 0.51 h−1, and the partition coefficient from 0.005 to 3.9 m, and these parameters vary greatly from one volatile organic compound/material couple to another indicating contrasted sorption behaviors. A rubber was identified as a sink of formaldehyde characterized by a very low desorption constant close to 0. For these sorbent floorings identified, the adsorption rates of formaldehyde are from 2 to 4 times higher than those of toluene. Two models were used to evaluate the sink effects of floorings on indoor pollutant concentrations in one room from different realistic conditions. The scenarios tested came to the conclusion that the formaldehyde sorption on one rubber (identified as a sink) has a maximum contribution from 15% to 21% for the conditions of low air exchange rate. For other floorings, the sorption has a minor contribution less than or equal to 5%, regardless of the air exchange rate. 相似文献
4.
Pierre Santucci Christina Dedaki Alexandros Athanasoulis Laura Gallorini Anaïs Munoz Dr. Stéphane Canaan Dr. Jean-François Cavalier Dr. Victoria Magrioti 《ChemMedChem》2019,14(3):349-358
In the quest for new antibacterial agents, a series of novel long- and medium-chain mono- and disubstituted β-lactones was developed. Their activity against three pathogenic mycobacteria—M. abscessus, M. marinum, and M. tuberculosis—was assessed by the resazurin microtiter assay (REMA). Among the 16 β-lactones synthesized, only 3-hexadecyloxetan-2-one (VM005) exhibited promising activity against M. abscessus, whereas most of the β-lactones showed interesting activities against M. marinum, similar to that of the classical antibiotic, isoniazid. Regarding M. tuberculosis, six compounds were found to be active against this mycobacterium, with β-lactone VM008 [trans-(Z)-3-(hexadec-7-en-1-yl)-4-propyloxetan-2-one] being the best growth inhibitor. The promising antibacterial activities of the best compounds in this series suggest that these molecules may serve as leads for the development of much more efficient antimycobacterial agents. 相似文献
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Previous experimental results indicate that the humidification conditions at the anode have an impact on the liquid water distribution in the cathode gas diffusion layer. Numerical simulations are developed to reproduce and analyze this effect. Results consistent with the experimental results are first obtained by playing with the partition coefficients of an advanced pore network model computing the liquid water formation and transfer in the cathode gas diffusion layer (GDL) for a large range of operating conditions. Then, a model for the full anode – cathode assembly is developed by combining the pore network model of the cathode GDL and a 1D model describing the heat and water transfer in the various components of the anode-cathode assembly. This enables one to generalize the dry – wet regime diagram introduced in a previous work by incorporating the effect of the humidity condition at the anode. 相似文献
6.
Alexandros Papadopoulos Issaak Parcharidis Panagiotis Elias Pierre Briole 《International journal of remote sensing》2019,40(16):6365-6382
We analysed the ground deformation across two blocks defined by the Rio-Patras fault from 1993 to 2017 using multi-temporal Synthetic Aperture Radar Interferometry (InSAR) techniques. Our main objective was to contribute to the assessment of seismic hazard near the large city of Patras. Multiple data-sets were used, each one covering different temporal periods. Descending and ascending acquisitions, providing different viewing geometries contribute to fully determine the ground displacement in 3D. The data-sets used are from the European Space Agency’s (ESA) European Remote Sensing (ERS), Environmental Satellite (ENVISAT) and SENTINEL-1 as well as German Aerospace Center (DLR) ’s TERRASAR-X missions. Considering ESA’s missions covering both acquisition geometries and long periods, the southern block, showing lack of a sufficient number of scatterers does not allow the displacement characterization. In contrary, the northern block is characterized by a high number of scatterers having values of maximum likehood ranging from ?3.5 to ?4.3 mm year?1 for ascending geometry and from ?1.6 to ?2.7 mm year?1 for the descending one. The fact that both geometries show negative values of displacements are consistent with downlift movement and at the same time the quantitative differentiation probably indicates an horizontal component as well. 相似文献
7.
Frédéric Gaschet 《Papers in Regional Science》2002,81(1):63-81
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
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Patrick DAstous Franoise Dtienne Willemien Visser Pierre N. Robillard 《Design Studies》2004,25(6):625-655
By contrast to design meetings, design evaluation meetings (DEMs) have generally been considered as situations in which, according to DEM methodologies, design activities are quite marginal. In a study of DEMs in software development, i.e. in technical review meetings following a particular review methodology, we showed: (i) the occurrence of design activities as part of an argumentation process; (ii) the relative importance of cognitive synchronisation as a prerequisite for evaluation; (iii) the important role played in evaluation by argumentation that makes explicit the underlying design rationale (DR). On the basis of our results, we discuss the potential for using DR methodologies in this kind of meetings. 相似文献
10.
Penetration of molten pitch into a coke bed is correlated with thermodynamic properties of pitch and of pitch-coke interfaces, as well as with the rheology of the liquid. A review of the possible relation between the above properties and the molecular properties of the pitch is presented. 相似文献