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91.
H. Dumont B. Delaunay J. Delaunay D.M. De Castro Rizzo A. Brondi P. Cuzzocrea A. Donofrio R. Moro M. Romano F. Terrasi 《Nuclear Physics A》1985,435(1):301-316
Excitation functions of the reactions 12, 13C+48Ti and 30Si+30Si were measured by in-beam γ-ray spectrometry in the energy ranges 20–60 MeV for the 12, 13C induced reactions and 55–126 MeV for the 30Si+30Si reaction. Light-particle angular distributions were measured at 46 MeV and 47.5 MeV for the 13C and 12C induced reactions. Measurements of elastic scattering angular distribution and particle-γ coincidences were carried out for the system 13C+48Ti at 46 MeV. The limitation to complete fusion detected for the system 30Si+30Si appears to be related to entrance channel effects and is well reproduced by a barrier penetration calculation using the KNS potential. The angular distribution measurements carried out for the 12C+48Ti and 13C+48Ti systems allowed to identify an incomplete fusion mechanism with emission of direct α-particles before the formation of a fully equilibrated system. 相似文献
92.
M. Clarembeau A. Cravador W. Dumont L. Hevesi A. Krief J. Lucchetti D. Van Ende 《Tetrahedron》1985,41(21):4793-4812
This paper reports our results concerning the syntheses of various bis(alkylseleno)alkanes and some of their arylseleno analogues by different methods. The scope and limitation of each of them are presented. 相似文献
93.
T. Dumont S. Lazare T. Lippert A. Wokaun 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1271-1274
The ablation rates of a polyimide and a triazene polymer were studied gravimetrically by a quartz micro balance for 248-nm and 308-nm irradiation. Special care was taken to examine the dependence of the ablation rate at constant fluences for single pulses and the influence of consecutive pulses at the same position. A clear trend was observed in these measurements, i.e., that the mass loss after the first pulse is always different from values for the following pulses. This implies that it is very difficult to determine true ablation rates, which are the foundation of most ablation models. The differences of the mass loss between the first pulse and the following pulses is most probably due to carbonization of the material, resulting in varying ablation rates for the following pulses. The ablation rates are thus not a real material property but a superposition of the material ablation rates with the ablation rates of carbon and carbonized material. PACS 52.38.Mf; 71.20.Rv; 07.10.Lw 相似文献
94.
The reversible cis-trans photoisomerization of disperse red 1 (DR1) in PMMA thin films has been demonstrated to be strongly polarization sensitive [1]. In this communication two mechanisms are identified: the angular hole burning and the angular redistribution of molecules. It is shown that, in the presence of a DC electric field, the redistribution is not centrosymmetric and produces a poling of the film. The evolution of the second-order nonlinear susceptibility, (2), is monitored by measuring the electro-optic effect by attenuated total reflection and by second-harmonic generation. 相似文献
95.
Bontempo D Heredia KL Fish BA Maynard HD 《Journal of the American Chemical Society》2004,126(47):15372-15373
In this communication we report a strategy for the synthesis of semitelechelic polymers reactive to cysteines. An initiator modified with a pyridyl disulfide was prepared and used for the CuBr/2,2'-bipyridine-mediated atom transfer radical polymerization (ATRP) of 2-hydroxyethyl methacrylate. Polydispersity indices (M(w)/M(n)) of the polymers with different molecular weights were 1.25 or less. The pyridyl disulfide end group was preserved during the polymerization and allowed direct conjugation of the polymer to cysteine residues of bovine serum albumin. The described method provides a general way for the preparation of protein-polymer conjugates through a reversible disulfide bond without the need for postsynthesis modification of the polymers. 相似文献
96.
Debora?S.?F.?Gay Yoshitaka?Gushikem Celso?C.?Moro Tania?M.?H.?Costa Edilson?V.?BenvenuttiEmail author 《Journal of Sol-Gel Science and Technology》2005,34(2):189-195
1,4-phenylenediamine-1-propylsilica hybrid xerogels were obtained for two composition at different temperatures of gelation, from 5 up to 70C. The morphological effects produced by the different gelation temperatures were investigated by using N2 adsorption-desorption isotherms and scanning electron microscopy. The thermal stability of the organic groups and their distribution on the xerogel matrix, i.e. the fraction of the organic groups that were trapped in closed pores, formed during the xerogel synthesis, and the fraction of organic groups present on the surface, were obtained by using infrared thermal analysis. The higher porosity of the xerogels and the higher thermal stability of the organic groups were achieved for samples gelled at 25C. 相似文献
97.
Mariana Alarcón-Correa Debora Walker Tian Qiu Peer Fischer 《The European physical journal. Special topics》2016,225(11-12):2241-2254
This minireview discusses whether catalytically active macromolecules and abiotic nanocolloids, that are smaller than motile bacteria, can self-propel. Kinematic reversibility at low Reynolds number demands that self-propelling colloids must break symmetry. Methods that permit the synthesis and fabrication of Janus nanocolloids are therefore briefly surveyed, as well as means that permit the analysis of the nanocolloids’ motion. Finally, recent work is reviewed which shows that nanoagents are small enough to penetrate the complex inhomogeneous polymeric network of biological fluids and gels, which exhibit diverse rheological behaviors. 相似文献
98.
Sofia Trakhtenberg Ramya Kumar Jason Bianchini Savin Thor Debora M. Martino 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1311-1315
Photocrosslinking of thymine‐based water‐soluble polymer films was investigated at varying preparation conditions. Adding salt or decreasing the pH of the solution from which the films were cast resulted in the decreased efficiency of photoimmobilization, while increasing the pH was found to increase the photoimmobilization efficiency. A mechanistic rationale for the observed effects is proposed. 相似文献
99.
100.
Back Cover: Amino Acid Oxidation: A Combined Study of Cysteine Oxo Forms by IRMPD Spectroscopy and Simulations (Chem. Eur. J. 48/2016) 下载免费PDF全文