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901.
The method of Garber and Wilson for SO(2) determination has been tested on real samples of air. The results demonstrate the possibility of simultaneous determination of SO(2), NO and NO(2) in the sample. Detection limits as low as 7 mul/m(3) for SO(2) and about 50 mul/m(3) for nitric oxides can be reached. 相似文献
902.
A Si(111) surface has been derivatized with a thiophene-terminated alkyl monolayer which was subsequently photoanodically oxidized in the presence of thiophene to yield a strongly adherent and smooth conducting film. 相似文献
903.
Bruno Ameduri Thierry Billard Bernard Langlois 《Journal of polymer science. Part A, Polymer chemistry》2002,40(24):4538-4549
The photochemical‐induced telomerization of vinylidene fluoride (VDF) with cyclohexyl (or phenyl) trifluoromethanethiosulfonate (CF3SO2SR), leading to CF3(VDF)nSR telomers, where R stands for cyclohexyl or phenyl, is presented. These sulfurated transfer agents were synthesized by the reaction between sodium triflinate (CF3SO2Na) and disulfide in the presence of bromine. 19F NMR spectroscopy enabled an assessment of the average degrees of telomerization (DPn) of these telomers with a neat CF3 end group as the label. These DPn values increased for higher [VDF]0/[CF3SO2SR]0 initial molar ratios. Interestingly, the normal/reversed ratio of VDF units in these telomers was low. Finally, the cotelomerization of VDF and hexafluoropropylene with these transfer agents was successfully achieved, leading to original ω‐CF3 fluoroelastomers, the thermal properties of which were investigated. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4538–4549, 2002 相似文献
904.
An increasing number of inter- and intramolecular interactions can nowadays be probed using single-molecule manipulation techniques. Protein unfolding and refolding is the most representative--though complex--of these interactions. Herein, we review the main modes of performing a force unfolding experiment: the velocity clamp and the new force clamp mode. We also compare some of the physical aspects behind the two most frequently used single-molecule manipulation instrumentations: optical tweezers and atomic force microscopes. 相似文献
905.
High-performance liquid chromatographic evaluation of Med 15 and its metabolites Med 5 and tolmetin in rat plasma. 总被引:1,自引:0,他引:1
A Mancinelli G Bruno G Cardace E Morabito A Marzo E Arrigoni Martelli 《Journal of chromatography. A》1991,553(1-2):81-86
A simple and reliable high-performance liquid chromatographic method is described for the quantitative analysis of the new non-steroidal anti-inflammatory agent Med 15 and its metabolites Med 5 and tolmetin in rat plasma. After selective extraction the three analytes and an internal standard (p-phenyl-phenol) were separated on a reversed-phase Ultrasphere 5 micron column using potassium dihydrogenphosphate (0.05 M)-acetonitrile (52:48) (pH 4.7) as the mobile phase. The analytes were detected at 313 nm; the sensitivity of the method proved to be 0.05 microgram/ml for all three compounds. The method has been applied to investigate Med 15 pharmacokinetics in rats. 相似文献
906.
Bruno A. Latella Michel Ignat Christophe J. Barbé David J. Cassidy John R. Bartlett 《Journal of Sol-Gel Science and Technology》2003,26(1-3):765-770
The mechanical properties of organically modified silicate coatings on stainless steel substrates were investigated, using nano-indentation and simultaneous in situ microtensile testing/optical microscopy. The load-displacement response and fracture behaviour is examined to ascertain the effects of different organic groups on the film properties and adhesion characteristics. The relationship between the morphology and mechanical properties of the films is discussed, and it is demonstrated that the mechanical response of the coatings is significantly influenced by the nature of the organic group attached to the ormocer precursor. 相似文献
907.
Bruno O. Villoutreix Olle Teleman Björn Dahlbäck 《Journal of computer-aided molecular design》1997,11(3):293-304
Protein S (PS), which functions as a species-specific anticoagulant cofactor to activated protein C (APC), is a mosaic protein that interacts with the phospholipid membrane via its -carboxyglutamate-rich (Gla) module. This module is followed by the thrombin-sensitive region (TSR), sensitive to thrombin cleavage, four epidermal growth factor (EGF)-like modules and a last region referred to as the sex hormone binding globulin (SHBG) domain. Of these, the TSR and the first EGF-like regions have been shown to be important for the species-specific interaction with APC. Difficulties in crystallising PS have so far hindered its study at the atomic level. Here, we report theoretical models for the Gla and EGF-1 modules of human PS constructed using prothrombin and factor X experimental structures. The TSR was built interactively. Analysis of the model linked with the large body of biochemical literature on PS and related proteins leads to suggestions that (i) the TSR stabilises the calcium-loaded Gla module through hydrophobic and ionic interactions and its conformation depends on the presence of the Gla module; (ii) the TSR does not form a calcium binding site but is protected from thrombin cleavage in the calcium-loaded form owing to short secondary structure elements and close contact with the Gla module; (iii) the PS missense mutations in this region are consistent with the structural data, except in one case which needs further investigation; and (iv) the two PS faces involving regions of residues Arg49–Gln52–Lys97 (TSR-EGF-1) and Thr103–Pro106 (EGF-1) may be involved in species-specific interactions with APC as they are richer in nonconservative substitution when comparing human and bovine protein S. This preliminary model helps to plan future experiments and the resulting data will be used to further validate and optimise the present structure. 相似文献
908.
Bruno Ameduri Bernard Boutevin Mustapha Nouiri 《Journal of polymer science. Part A, Polymer chemistry》1993,31(8):2069-2080
The radical grafting of CnF2n +1 CH2CH2SH (n = 6,8) onto the double bonds of hydroxyl-terminated liquid polybutadienes (HTPBD) was studied. Various methods for investigating the amount of grafting (titration of residual thiol and fluorine analysis) were used and compared. The nature and the amount of the initiator, the quantity of thiol, the temperature and the time of the reaction. the solvent, and the microstructure of HTPBD were optimized. The kinetic aspect showed that the thiol disappeared according to a first-norder law. A method using up to 100% of grafting fluorinated mercaptan was described and standards were set up with fluorine contents of 5–59% to evaluate the physicochemical properties of these thioether group-containing polymers: solubility, refractive index, intrinsic and dynamic viscosities, and thermal characteristics (glass transition and decomposition temperatures). Finally, the surface properties of these standards showed improvements of surface energy as low as 9 mN m?1 for a totally saturated fluorinated HTPBD. © 1993 John Wiley & Sons, Inc. 相似文献
909.
Representations of the Lie algebra sl(3) with highest weight are analyzed. Invariant subspaces of indecomposable representations are determined. We study the decomposition of these representations with respect to the subalgebras su(2) and su(1,1) (in their obvious imbedding in su(2,1)).For special cases this decomposition gives indecomposable non multiplicity free representations (indecomposable pairs) with highest weight. These were discussed in [1] and appear also in the decomposition so(3,2) su(1,1) of the Rac representation, [7]. 相似文献
910.
Bruno Kisch 《Colloid and polymer science》1929,49(2):156-158
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