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排序方式: 共有488条查询结果,搜索用时 15 毫秒
61.
Ali Bagheri Jonathan Yeow Hamidreza Arandiyan Jiangtao Xu Cyrille Boyer May Lim 《Macromolecular rapid communications》2016,37(11):905-910
The polymerization of the photocleavable monomer, o‐nitrobenzyl methacrylate (NBMA), is investigated using photoinduced electron/energy transfer reversible addition‐fragmentation chain transfer polymerization. The polymerizations under visible red (λ max = 635 nm, 0.7 mW cm−2) and yellow (λ max = 560 nm, 9.7 mW cm−2) light are performed and demonstrate rational evidence of a controlled/living radical polymerization process. Well‐defined poly(o‐nitrobenzyl methacrylate) (PNBMA) homopolymers with good control over the molecular weight and polymer dispersity are successfully synthesized by varying the irradiation time and/or targeted degree of polymerization. Chain extension of a poly(oligo(ethylene glycol) methyl ether methacrylate) macro‐chain transfer agent with NBMA is carried out to fabricate photocleavable amphiphilic block copolymers (BCP). Finally, these self‐assembled BCP rapidly dissemble under UV light suggesting the photoresponsive character of NBMA is not altered during the polymerization under yellow or red light. Such photoresponsive polymers can be potentially used for the remote‐controlled delivery of therapeutic compounds.
62.
Piraud M Vianey-Saban C Bourdin C Acquaviva-Bourdain C Boyer S Elfakir C Bouchu D 《Rapid communications in mass spectrometry : RCM》2005,19(22):3287-3297
Seventy-six compounds of biological interest for the diagnosis of inherited disorders of amino acids (AA) metabolism have previously been demonstrated to be detectable in positive mode electrospray ionisation tandem mass spectrometry (ESI-MS/MS), after separation by ion-pairing reversed-phase liquid chromatography (RPLC). The separation method used tridecafluoroheptanoic acid as ion-pairing agent, and a gradient of acetonitrile for the elution of the most retained compounds. This method had previously been demonstrated to be suitable for the qualitative diagnosis of many AA disorders, and for the quantitative measurement of 16 AA in biological fluids, using their stable isotope labelled (SIL) AA as internal standard. For quantification of the other AA, an internal standard was chosen among the available SIL-AA, as close as possible to the analyte to be measured, in terms of structural analogy, and of retention time in the chromatographic system. The performances of the quantitative analysis of the other AA to be measured are reported here. They show validated results for several AA, allowing their accurate quantification, with another SIL-AA as internal standard. For some other AA, quantitative results were not accurate, allowing only semi-quantitative or qualitative determination for these parameters. 相似文献
63.
Boyer Steven; Gordon Cameron McA.; Zhang Xingru 《Journal London Mathematical Society》2009,79(1):72-84
We show that the distance between a finite filling slope anda reducible filling slope on the boundary of a hyperbolic knotmanifold is one. 相似文献
64.
François-Didier Boyer 《Tetrahedron letters》2005,46(31):5177-5180
The synthesis of dimeric flavanols is the consequence of the possible trapping of the reaction intermediates generated in the course of the reductive hydrogenation of substituted benzaldehydes. The scope of this reaction is investigated. 相似文献
65.
Molecular Diversity - 相似文献
66.
The diffusive motions of hydrogen in amorphous Zr2Ni hydrides were observed by181Ta PAC relaxation measurements. The comparison with the experimental data obtained for crystalline Zr2Ni hydride lead to the conclusion that hydrogen loading induce a short-range ordering into the amorphous structure. The absence
of a large distribution of activation energies may be a consequence of such ordering and/or of collective effects in the hydrogen
diffusion processes
Affiliated to the Centre National de la Recherche Scientifique. 相似文献
67.
J. C. Elicer-Corts R. Contreras D. Boyer M. Pavageau R. H. Hernndez 《Experimental Thermal and Fluid Science》2004,28(8):1205-813
This paper reports the results of a study on temperature inhomogeneities conducted on a thermal plume by using ultrasound scattering as a non-intrusive measurement technique. The plume rises from a metallic disk which can be heated up to 800 °C. The working fluid is air at atmospheric pressure. In the measurement technique, an incoming ultrasound wave is emitted towards the thermal plume. The incident wave is scattered because of non-linear couplings with the flow instabilities present in the measurement region. The scattered wave carries information about those flow instabilities. The technique allows for the retrieving of this information. The shape of the obtained spectrum of temperature fluctuations as a function of wave vector modulus
is consistent with previous theoretical analysis. Three qualitatively different regions were identified: first, a production region characterized by a q2 law; secondly, a region with behavior as per q−3 associated with a buoyancy region and; finally, a dissipation region associated with a q−7 law. These spectral regions characterize the energy transfers mechanisms among the length scales of flow investigated here. A coefficient of anisotropy γ was defined to analyze anisotropic features of the flow. 相似文献
68.
Robson B Li J Dettinger R Peters A Boyer SK 《Journal of computer-aided molecular design》2011,25(5):427-441
A patent data base of 6.7 million compounds generated by a very high performance computer (Blue Gene) requires new techniques
for exploitation when extensive use of chemical similarity is involved. Such exploitation includes the taxonomic classification
of chemical themes, and data mining to assess mutual information between themes and companies. Importantly, we also launch
candidates that evolve by “natural selection” as failure of partial match against the patent data base and their ability to
bind to the protein target appropriately, by simulation on Blue Gene. An unusual feature of our method is that algorithms
and workflows rely on dynamic interaction between match-and-edit instructions, which in practice are regular expressions.
Similarity testing by these uses SMILES strings and, less frequently, graph or connectivity representations. Examining how
this performs in high throughput, we note that chemical similarity and novelty are human concepts that largely have meaning
by utility in specific contexts. For some purposes, mutual information involving chemical themes might be a better concept. 相似文献
69.
70.
Petradza M Thun R Abrams G Amidei D Baden AR Barklow T Boyarski A Boyer J Burchat PR Burke DL Butler F Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Haggerty J Jaros JA Kadyk JA Karlen D Lankford AJ Larsen RR LeClaire BW Levi ME Lockyer NS Lüth V Nelson ME Ong RA Perl ML Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH Wood DR Yelton JM 《Physical review D: Particles and fields》1990,42(7):2171-2179