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81.
    
The cell-wall composition has been analyzed for 13 batches of flax fibers grown over 3 years under 3 different weather conditions including a ‘normal one, a harsh drought and a rainy weather. It was found that both stresses, drought and excess of rain induced a decrease of uronic acid in the matrix and an increase of the structuring pectins. Besides, a drought led to an increase of hemicellulose polysaccharides (+24%) whereas an excess of rainfall caused a rise in the amount of so-called structuring pectins (+67%). As the fiber’s mechanical properties remained the same over the years, it was assumed that the cell-wall composition was modified to preserve the mechanical role of the fiber in the stem.  相似文献   
82.
    
In slurry and gas phase catalytic ethylene polymerization processes, aluminum alkyl (AlR3) compounds are usually present inside the reactor and their role either as co‐catalyst or scavenger is of considerable importance. Silica supported metallocene/methyl aluminoxane (MAO) catalysts show specific interactions with AlR3 compounds. Therefore, this study shows an attempt to analyze and compare the effect of concentration as well as type of commonly used AlR3 on slurry phase ethylene homopolymerization kinetics of silica supported (n‐BuCp)2ZrCl2/MAO catalyst. The obtained results indicate that the lower the concentration of smaller AlR3 compounds, the higher the instantaneous catalytic activity. Concerning the polymer particle size distributions, a rise in fines generation has been observed with increasing AlR3 content inside the reactor. Finally, it has been shown that the addition of 2,6‐di‐tert‐butyl‐4‐methylphenol (a substituted phenol) into the reactor containing AlR3 reduces the influence of AlR3 compounds on the reaction kinetics of silica supported metallocene/MAO catalysts. Polyethylene properties remain similar in all the studied scenarios. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45670.  相似文献   
83.
    
Within the framework of the MABMEM research project, new high‐performance membranes are being developed for sustainable water management. The performance of the membranes will be evaluated in comparative and standardized fouling tests as well as in terms of the removal of trace impurities on a laboratory scale. Seven candidates are currently being tested in demonstrator trials with real‐water matrix in a waterworks for the direct treatment of dam water without prior coagulation over a period of 6 months. Subsequently, the new membrane materials will be operated with the effluent of a wastewater treatment plant.  相似文献   
84.
    
A family of bi- and tetrametallic gold(I) phosphine dithiocarbamate complexes were synthesized, starting from cyclam and dimethylcyclam polyazamacrocycles, respectively, along with their monometallic gold(I) chloridophosphine precursors. Their antiproliferative properties were evaluated on two cancer cell lines (A549 and NSCLC-N6-L16). Most of the mono- and bimetallic complexes displayed strong activities and, in particular, one bimetallic derivative showed antiproliferative properties in the low micromolar range. Insights into the structure–activity relationships are given, along with determination of the thioredoxin reductase inhibition potential, two-photon imaging of the fluorescent derivatives, and evaluation of gold uptake.  相似文献   
85.
    
A selective production of pyrrolidines vs pyrrolidinones via hydrosilylation of levulinic acid and levulinates by switching of the iron complex catalyst is presented herein. The reactions proceeded efficiently with various anilines and alkylamines under both visible light irradiation and thermal conditions with 43 examples in isolated yields up to 93%. Noticeably, under similar conditions, cyclic amines such as piperidines and azepanes were efficiently synthesized with yields up to 92%, by reaction of anilines with 1,5‐ or 1,6‐keto acids, respectively. Similarly, N‐arylinsolidoline compounds can be prepared from 2‐formylbenzoic acid in 57–93% yields.

  相似文献   

86.
The synthesis and anti-HIV evaluation of hitherto unknown 3′-fluoro-5′-norcarbocyclic nucleoside phosphonates bearing adenine with modifications at the 4′ position (ethynyl, vinyl, ethyl, hydroxymethyl) is described. One of the synthesized compounds was found to be an inhibitor of HIV-1 replication, but with moderate efficiency relative to (R)-9-(2-phosphonylmethoxypropyl)adenine ((R)-PMPA, tenofovir), with no concomitant cytotoxicity.  相似文献   
87.
    
This article shows the role that fuzzy sets may play in the prospect of analysing qualitative data. To underline this role, a human-computer interaction (HCI) study is presented. The data coming from 20 experts concerns their judgment regarding 33 questions related to the use of HCI approaches in order to support interactive system development phases. Each response scale features three main modalities, that is Agree, Partially agree and Disagree. The dataset example is analysed using multiple correspondence analysis (MCA) with both crisp and fuzzy coding models where the intermediate modality, Partially agree, is removed and considered with ½ membership values to the two extreme modalities. A comparative analysis is performed and the discussion states the interest of fuzzy coding with several kinds of qualitative factors or measurement variables. With qualitative measurement variables (our example), the main drawback of fuzzy coding could be the information loss, which is counterbalanced by the possibility of having fewer modalities and therefore of simplifying the multivariate analysis.  相似文献   
88.
    
In this article, the use of thin, photocatalytically active TiO2 films deposited using atomic layer deposition (ALD) and a conventional lithography mask are explored for the fabrication of a patterned biointerface. Hereto, a pattern of self‐assembled monolayers (SAMs) with different functional groups is created using ALD TiO2 films, anatase‐rich as‐deposited, with a thickness of 20 nm and a short UV exposure time of 5 min. More specifically, azido‐containing SAMs are locally removed upon UV exposure (λ = 308 nm) and the created gaps are filled with a polyethylene glycol (PEG) SAM, hereby creating a surface with areas for the selective coupling of biomolecules via the azide groups and antifouling areas due to the presence of the PEG. To demonstrate the effectiveness of this approach, fluorescent‐labeled antibodies are immobilized on the well‐defined patterns with a resolution in the µm range.  相似文献   
89.
The medical community is producing and manipulating a tremendous volume of digital data for which computerized archiving, processing and analysis is needed. Grid infrastructures are promising for dealing with challenges arising in computerized medicine but the manipulation of medical data on such infrastructures faces both the problem of interconnecting medical information systems to Grid middlewares and of preserving patients’ privacy in a wide and distributed multi-user system. These constraints are often limiting the use of Grids for manipulating sensitive medical data. This paper describes our design of a medical data management system taking advantage of the advanced gLite data management services, developed in the context of the EGEE project, to fulfill the stringent needs of the medical community. It ensures medical data protection through strict data access control, anonymization and encryption. The multi-level access control provides the flexibility needed for implementing complex medical use-cases. Data anonymization prevents the exposure of most sensitive data to unauthorized users, and data encryption guarantees data protection even when it is stored at remote sites. Moreover, the developed prototype provides a Grid storage resource manager (SRM) interface to standard medical DICOM servers thereby enabling transparent access to medical data without interfering with medical practice.  相似文献   
90.
This paper describes a multi-agent coordination mechanism applied to intersection simulation situations. In a goal of urban traffic simulation, we must consider the dynamic interactions between autonomous vehicles. The field of multi-agent systems provides us some studies for such systems, in particular on the coordination mechanisms. Conflicts between vehicles (i.e. agents) are very frequent in such applications, and they may cause deadlocks, particularly at intersections such as crossroads. Our approach is based on the solving of two player games/decision matrices which characterize three basic situations. An aggregation method generalizes to n-player games for complex crossroads. The objective of this approach consists in searching basic two-player matrices for solving n-agent problems. To explain the principle, we describe our approach for a particular case of crossroad with three agents. Finally, the obtained results have been examined via a tool of road traffic simulation, ARCHISIM. We assume also that the global traffic replicates the behavior of agents in different situations.  相似文献   
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