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291.
Carazzone C Colombo R Quaglia M Mangione P Raimondi S Giorgetti S Caccialanza G Bellotti V De Lorenzi E 《Electrophoresis》2008,29(7):1502-1510
Human beta2-microglobulin (beta2-m) is a small amyloidogenic protein responsible for dialysis-related amyloidosis, which represents a severe complication of long-term hemodialysis. A therapeutic approach for this amyloidosis could be based on the stabilization of beta2-m through the binding to a small molecule, to possibly inhibit protein misfolding and amyloid fibril formation. The search of a strong ligand of this protein is extremely challenging: by using CE in affinity and refolding experiments we study the effect that previously selected sulfonated molecules have on the equilibrium between the native form and an ensemble of conformers populating the slow phase of beta2-m folding. These data are correlated with the effect that the same molecules exert on in vitro fibrillogenesis experiments. 相似文献
292.
Starting from selection rules for intershell tunneling in double-walled nanotubes with commensurate (c-DWNTs) and incommensurate (i-DWNTs) shells, we show that for i-DWNTs the coupling is negligible between lowest energy subbands, but it becomes important as the higher subbands become populated. In turn the elastic mean-free path of i-DWNTs is reduced for increasing energy, with additional suppression at subband onsets and crossings. At low energies, a Luttinger liquid theory for DWNTs with metallic shells is derived. Interaction effects are more pronounced in i-DWNTs than in c-DWNTs. 相似文献
293.
Two-photon imaging with thermal light 总被引:3,自引:0,他引:3
We report the first experimental demonstration of two-photon imaging with a pseudothermal source. Similarly to the case of entangled states, a two-photon Gaussian thin lens equation is observed, indicating EPR type correlation in position. We introduce the concepts of two-photon coherent and two-photon incoherent imaging. The differences between the entangled and the thermal cases are explained in terms of these concepts. 相似文献
294.
Miroslav Holík Milena Ture
kov Jan Vymtal 《Magnetic resonance in chemistry : MRC》1984,22(10):621-623
The structures of seven polysubstituted alkylpyridines, recently isolated from coal tar, were elucidated using their 13C NMR spectra. For tri- and tetra-substituted derivatives the correct isomeric structure was found from their conformity with the proximity effect, i.e. the deviations from additivity when calculating chemical shifts from substituent increments (SCS) for sterically crowded molecules. This effect manifests itself both on the ring and on the alkyl carbon signals, and in most cases shifts their position upfield. 相似文献
295.
296.
Bertrand Morel Ania Selmi Laurent Moch Jean-Michel Hiltbrunner Mickael Achour Rachid Benzouaa Aurélien Bock Laurent Jouffret Pierre Bonnet André Hamwi Marc Dubois 《Comptes Rendus Chimie》2018,21(8):782-790
The present article reviews a selection of results obtained in the AREVA/CNRS/UCA joint research laboratory. It focuses on interfaces formed by uranium hexafluoride (UF6) with chemical filter (purification), carbon (UF6 storage), and metallic substrate (corrosion). As a matter of fact, along the nuclear fuel cycle, metallic surfaces of the fluorination reactors, cooling systems (for the liquefaction of UF6), and storage containers are in contact with UF6, either in the gas or in the liquid phase. For the removal of volatile impurities before the enrichment, surface of chemical filters with a high specific surface area must be enhanced for both selectivity and efficiency. To store depleted UF6 (238U), graphite intercalation compounds are proposed and preliminary results are presented. 相似文献
297.
Stanković Milena Antić Gordana Blagojević M. Petrović S. 《Journal of Thermal Analysis and Calorimetry》1998,52(2):581-585
The method of microcalorimetric compatibility testing of the constituents of combustible materials and casting composite explosives
is based on the change in power when separately measuring the different materials involved, and their mixture, during isothermal
treatment. The experimental power-time curve for the mixture was compared to the hypothetical curve constructed from the results
of the measurements of individual materials.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
298.
Lombaert K. Morel S. Le Moyne L. Adam P. Tardieu de Maleissye J. Amouroux J. 《Plasma Chemistry and Plasma Processing》2004,24(1):41-56
The main methods of identification and quantification of metallic species in diesel soot require to render metallic species soluble by destruction of solid sample with all the difficulties associated to this analysis such as rate of solubility, destruction of sample, risk of sample pollution during preparation step. Furthermore, a few milligrams of sample are used, then lost and another analysis is not permitted. This article describes a new direct analysis of metals presents in exhaust particles and collected on a filter by using the TRELIBS (Time Resolved Laser Induced Breakdown Spectroscopy), which avoids the complete destruction of the sample. In a few a milliseconds, it is possible to obtain a qualitative and semi-quantitative composition of a complex matrix as diesel particulates: Fe, Mg, Ca, Cu, and Zn appear as the major metallic species. TRELIBS results are compared to SEM/EDS. After a presentation of the properties required by the filter for TRELIBS analysis, the identification of the metallic species collected in the exhaust gas of a diesel engine is presented and compared with another technique (SEM/EDS). The evolutions of the metallic concentrations in diesel particles for different air/fuel ratio are also presented. 相似文献
299.
Antoine Gautier Christian Vial Cdric Morel Marina Lander Ferdinand Nf 《Helvetica chimica acta》1987,70(8):2039-2044
The enantiomeric decahydro-2-naphthalenols (+)- 5 and (?)-5 were prepared by enantioselective hydrolysis of the racemic chloroacetate (±)- 2 catalyzed by porcine pancreatic lipase, and converted to the corresponding acetates (+)- 1 and (?)- 1 and ketones (+)- 6 and (?)- 6 . The absolute configurations of the ketones, alcohols, and acetates were established by chemical correlation with natural manool ((+)- 7 ) by making use of a retro-ene cleavage reaction of the known manool degradation product 8 to (?)- 6 . A distinct odour difference between the two enantiomers of each pair (+)- 1 /(?)- 1 and (+)- 6 /(?)- 6 has been found. 相似文献
300.
Jean Michel Morel 《manuscripta mathematica》1985,54(1-2):165-185
In this paper, we describe a method for extending (in some approximated sense) solutions of a nonlinear P.D.E. on a domain , to solutions in a domain containing . Such an extension property, the Runge property, is well known for a large class of linear problems including elliptic equations. We prove here the Runge property for semilinear problems of the kind -u+g(u)=f, with f L
loc
1
(N). (As a consequence, we get infinitely many solutions for these problems). The proof is based on a homotopy method, and requires a refinement of the linear results: We prove that the Runge extension v on of a solution u in for a linear elliptic equation Lu=f can be choosen in order to depend continuously on u and the coefficients of L. 相似文献