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81.
Barthélémy B Devillers S Minet I Delhalle J Mekhalif Z 《Journal of colloid and interface science》2011,354(2):873-879
Titanium and its alloys present high interests for technological applications due to their high corrosion resistance, mechanical properties and biocompatibility. In combination with these remarkable characteristics, some Ti applications require specific surface properties that can be imparted with suitable surface functionalizations of the TiO(2) oxide layer. The present work aims to study the surface-initiated ATR polymerization of styrene on titanium substrates, using grafted 11-(2-bromoisobutyrate)-undecyl-1-phosphonic acid as initiator and to compare the impact of two different heating ways on the efficiency of this polymerization: induction vs. conventional heating. The ability of the initiator to bind titanium substrates and act as an initiator for ATRP of styrene is investigated: both heating conditions led to the polymerization of styrene on modified titanium substrates. However, induction heating appeared to be much more efficient than conventional heating, leading to the formation of a thicker, much denser polystyrene layer than conventional heating after only 1h of polymerization. 相似文献
82.
Bastien Barthélémy Sébastien Devillers Isabelle Minet Joseph Delhalle Zineb Mekhalif 《Applied Surface Science》2011,258(1):466-473
Phynox is of high interest for technological applications due to its high corrosion resistance, mechanical properties and biocompatibility. In combination with these remarkable characteristics, some Phynox applications require specific surface properties that can be imparted with suitable surface functionalizations of the oxide layer. The present work aims at studying the surface-initiated atom transfer radical polymerization (ATRP) of 2-(methacryloyloxy)ethyl 2-(trimethylammonio)ethyl phosphate (MPC) on Phynox substrates, using grafted 11-(2-bromoisobutyrate)-undecyl-1-phosphonic acid as initiator. The ability of the initiator to bind Phynox substrates and act as an initiator for ATRP of MPC is investigated. It appears that ATRP polymerization of MPC on modified Phynox substrates already takes place in aqueous media at room temperature, but the yield at 90 °C is superior. 相似文献
83.
Alice Devillers Michael Giudici Cai Heng Li Cheryl E. Praeger 《European Journal of Combinatorics》2010,31(1):336-348
Two different constructions are given of a rank 8 arc-transitive graph with 165 vertices and valency 8, whose automorphism group is M11. One involves 3-subsets of an 11-set while the other involves 4-subsets of a 12-set, and the constructions are linked with the Witt designs on 11, 12 and 24 points. Four different constructions are given of a rank 9 arc-transitive graph with 55 vertices and valency 6 whose automorphism group is . This graph occurs as a subgraph of the M11 graph, and two of the constructions involve 2-subsets of an 11-set while the remaining two involve 3-subsets of an 11-set. The and M11 graphs occur as the second and third members of a tower of graphs defined on a conjugacy class of involutions of the simple groups A5, , M11 and M12 with two involutions adjacent if they generate a special S3. The first graph in the tower is the line graph of the Petersen graph while the fourth is the Johnson graph J(12,4). The graphs also arise as collineation graphs of rank 2 truncations of various residues of certain P-geometries. 相似文献
84.
Jean Devillers Doureid Houalla Jean Roussel Robert Wolf 《Magnetic resonance in chemistry : MRC》1976,8(10):500-504
The interpretation in terms of conformational analysis of 1H n.m.r. parameters of 1-phenyl-2,8-dioxa-5-aza-1-phosphav bicyclo[3.3.0]octane is consistent with a rigid envelope conformation for each 5-membered ring and a planar nitrogen atom. In the case of 1,6-dioxa-4,9-diaza-5-phosphavspiro[4.4]nonane, the same procedure shows librational motions around the C? C bond. 相似文献
85.
Recently, two main events have spurred a rapid increase in cyanobacteria chemical, toxicological, and ecological research. The first deals with the interest in isolating compounds from these organisms as source of active products with potential therapeutic applications. The second pertains the crucial problem of harmful cyanobacterial blooms in the aquatic environments. In this context, 594 secondary metabolites belonging to more than 30 genera of cyanobacteria were retrieved from literature. In order to perform their typology, they were first associated with 87 different molecular archetypes and two orphan classes. These 89 groups of molecular structures were then confronted to minimum spanning tree analysis. Attempts were made to graphically derive chemotaxonomical relationships. The interest of QSAR models for estimating the potential pharmacological interest of the cyanobacterial secondary metabolites was also discussed. 相似文献
86.
Devillers J Decourtye A Budzinskid H Pham-Delègue MH Cluzeau S Maurin G 《SAR and QSAR in environmental research》2003,14(5-6):389-403
The adverse effects of 158 pesticides to the Honey bee (Apis mellifera), the alfalfa leafcutting bee (Megachile rotundata) and the alkali bee (Nomia melanderi) were compared by means of various linear and non-linear multivariate analyses. A comparison exercise including the bumble bee (Bombus spp.) was also performed from a more restricted set of 32 pesticides. While no difference of sensitivity was found between A. mellifera and Bombus spp., M. rotundata appeared the most susceptible to pesticides followed by N. melanderi. 相似文献
87.
88.
A Composite of Complex and Chemical Hydrides Yields the First Al‐Based Amidoborane with Improved Hydrogen Storage Properties
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Iurii Dovgaliuk Lars H. Jepsen Dr. Damir A. Safin Prof. Zbigniew Łodziana Dr. Vadim Dyadkin Prof. Torben R. Jensen Prof. Michel Devillers Prof. Yaroslav Filinchuk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(41):14562-14570
The first Al‐based amidoborane Na[Al(NH2BH3)4] was obtained through a mechanochemical treatment of the NaAlH4–4 AB (AB=NH3BH3) composite releasing 4.5 wt % of pure hydrogen. The same amidoborane was also produced upon heating the composite at 70 °C. The crystal structure of Na[Al(NH2BH3)4], elucidated from synchrotron X‐ray powder diffraction and confirmed by DFT calculations, contains the previously unknown tetrahedral ion [Al(NH2BH3)4]?, with every NH2BH3? ligand coordinated to aluminum through nitrogen atoms. Combination of complex and chemical hydrides in the same compound was possible due to both the lower stability of the Al?H bonds compared to the B?H ones in borohydride, and due to the strong Lewis acidity of Al3+. According to the thermogravimetric analysis–differential scanning calorimetry–mass spectrometry (TGA–DSC–MS) studies, Na[Al(NH2BH3)4] releases in two steps 9 wt % of pure hydrogen. As a result of this decomposition, which was also supported by volumetric studies, the formation of NaBH4 and amorphous product(s) of the surmised composition AlN4B3H(0–3.6) were observed. Furthermore, volumetric experiments have also shown that the final residue can reversibly absorb about 27 % of the released hydrogen at 250 °C and p(H2)=150 bar. Hydrogen re‐absorption does not regenerate neither Na[Al(NH2BH3)4] nor starting materials, NaAlH4 and AB, but rather occurs within amorphous product(s). Detailed studies of the latter one(s) can open an avenue for a new family of reversible hydrogen storage materials. Finally, the NaAlH4–4 AB composite might become a starting point towards a new series of aluminum‐based tetraamidoboranes with improved hydrogen storage properties such as hydrogen storage density, hydrogen purity, and reversibility. 相似文献
89.
Alice Devillers 《组合设计杂志》2000,8(5):321-329
A linear space S is d‐homogeneous if, whenever the linear structures induced on two subsets S1 and S2 of cardinality at most d are isomorphic, there is at least one automorphism of S mapping S1 onto S2. S is called d‐ultrahomogeneous if each isomorphism between the linear structures induced on two subsets of cardinality at most d can be extended into an automorphism of S. We have proved in [11;] (without any finiteness assumption) that every 6‐homogeneous linear space is homogeneous (that is d‐homogeneous for every positive integer d). Here we classify completely the finite nontrivial linear spaces that are d‐homogeneous for d ≥ 4 or d‐ultrahomogeneous for d ≥ 3. We also prove an existence theorem for infinite nontrivial 4‐ultrahomogeneous linear spaces. © 2000 John Wiley & Sons, Inc. J Combin Designs 8: 321–329, 2000 相似文献
90.
ABSTRACTHuman malaria is the most widespread mosquito-borne life-threatening disease worldwide. In the absence of effective vaccines, prevention and treatment of malaria only depend on prophylaxis and drug-based therapy either in monotherapy or in combination. Unfortunately, the number of available antimalarial drugs presenting different mechanisms of action is rather limited. In addition, the appearance of drug-resistance in the parasite strains impacts the efficacy of the treatments. As a result, there is a crucial need to find new drugs to circumvent resistance problems. In the quest to identify new antimalarial agents a huge number of plant-derived compounds (PDCs) have been investigated. Surprisingly in the in silico PDC screening programs, toxicity filters are either never used or so simple that their interest is limited. In this context, the goal of this study was to show how to take advantage of validated toxicity QSAR models for refining the selection of PDCs. From an original data set of 507 PDCs collected from the literature, the use of toxicity filters for endocrine disruption, developmental toxicity, and hepatotoxicity in conjunction with classical pharmacokinetic filters allowed us to obtain a list of 31 compounds of potential interest. The pros and cons of such a strategy have been discussed. 相似文献