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101.
The theory of homogeneous nucleation is developed for a model nonlinear bistable chemical reaction driven far from equilibrium (trimolecular Schlögl model). The theory is restricted to the vicinity of the stable/unstable transition, where the nucleation barrier is small but nonvanishing. The nucleation rates are derived for two types of fluctuations: first, fluctuations due to a homogeneous external white noise source, and second, internal chemical fluctuations, described by a reastion-diffusion multivariate master equation. In the white noise case, a Landau-Ginzburg potential can be defined, and the standard nucleation formalism can be applied; this is not true for the internal case and a new result is used. The inhomogeneous chemical fluctuations, due to the coupling between the nonlinear reaction and diffusion, are shown to have an influence on the nucleation rate. Quantitative conditions are also given to evaluate the possibility of homogeneous nucleation in nonlinear chemical systems. 相似文献
102.
Bernard Gaveau James T. Hynes Raymond Kapral Michel Moreau 《Journal of statistical physics》1989,56(5-6):879-893
A class of stochastic processes is studied that can be used to model elementary and complex chemical reactions composed of a series of several distinct steps. Formal correlation function expressions are directly computed for the stochastic model to yield the overall rate constant for the reaction. One of the main results is a formula connecting the overall rate constant to the rate constants characterizing the elementary steps of the reaction. 相似文献
103.
104.
Coline Canovas Dr. Mathieu Moreau Dr. Claire Bernhard Dr. Alexandra Oudot Mélanie Guillemin Prof. Franck Denat Dr. Victor Goncalves 《Angewandte Chemie (International ed. in English)》2018,57(33):10646-10650
Dual‐labeled biomolecules constitute a new generation of bioconjugates with promising applications in therapy and diagnosis. Unfortunately, the development of these new families of biologics is hampered by the technical difficulties associated with their construction. In particular, the site specificity of the conjugation is critical as the number and position of payloads can have a dramatic impact on the pharmacokinetics of the bioconjugate. Herein, we introduce dichlorotetrazine as a trivalent platform for the selective double modification of proteins on cysteine residues. This strategy is applied to the dual labeling of albumin with a macrocyclic chelator for nuclear imaging and a fluorescent probe for fluorescence imaging. 相似文献
105.
Bachir Douara Yannick J. Esvan Elisabeth Pereira Francis Giraud Yulia L. Volodina Dmitry N. Kaluzhny Alexander A. Shtil Fabrice Anizon Pascale Moreau 《Tetrahedron》2018,74(8):892-901
Pyrazole analogs of the staurosporine aglycon K252c were recently described as potent inhibitors of the three Pim protein kinase isoforms. To evaluate the impact of the introduction of a sugar moiety on the biological activities of this heterocyclic scaffold, four new glucosylated pyrazole analogs of K252c were synthesized. Their biological evaluation demonstrated that most active compounds 11 and 19 substituted by a β-d-glucosyl moiety at N12 or N13 positions exhibited antiproliferative activities toward HCT116 cells. 相似文献
106.
We report the synthesis of a novel purine based amphiphile; di-oleyladenosinephosphocholine (DOAPC). Light microscopy, TEM and QELS studies on DOAPC in aqueous media support the formation of lamellar systems. These investigations indicate that the presence of adenine does not prohibit the formation of lamellar organizations. Stable small unilamellar vesicles can be prepared by using extrusion techniques. 相似文献
107.
Howard C. Haas Robert D. Moreau Norman W. Schuler 《Journal of Polymer Science.Polymer Physics》1967,5(5):915-927
The homopolymer and many of the copolymers of N-acrylylglycinamide yield thermally reversible gels in water. These systems are uniquely suitable for studying synthetic photographic gelatin substitutes and for understanding the mechanism of the gelation process. Polymerization of N-acrylylglycinamide has been studied under a variety of conditions. The homopolymer is aggregated in dilute aqueous solution and probably molecularly dispersed in 2M thiocyanate solution. At concentrations of several per cent, in water, thermally reversible gels are formed whose melting points rise with increasing concentration and increasing molecular weight. The heat of gelation crosslinking has been calculated to be ?8.8 kcal./mole of crosslinks. Introduction of small amounts of carboxyl groups into the polymer raises the melting points of the aqueous gels. The effect of various organic and inorganic reagents on gelation is presented. The ability to prepare copolymers which can be flocculated has been demonstrated as well as the usefulness of the monomer in certain types of photoresist systems. Copolymerization with acrylic acid and β-aminoethyl vinyl ether has been studied, and the r1 and r2 values for these systems have been calculated as well as Q and e values for N-acrylylglycinamide. 相似文献
108.
Ch Engelmann G. Filippi J. Gosset F. Moreau 《Journal of Radioanalytical and Nuclear Chemistry》1977,37(2):559-570
The photonuclear reactions used for this isotopic analysis are as follows:16O(γ, n)15O threshold energy 15.7 MeV;18O(γ, p)17N threshold energy 16.3 MeV.15O is a pure β+ emitter of half-life 2.03 minutes, whereas17N presents a 4.2 second neutron emission. The principle of the method is founded on the simultaneous measurement of the above
characteristic radioactivities, the intensities of which are proportional to the respective quantities of16O and18O present in the irradiated sample. The potentialities of this new oxygen isotope analysis method, based on the use of an
electron accelerator, are described. Detection limit of 0.1 μg18O is easily attainable. The equipment designed and built to industrialise this technique is described. It allows a hundred
samples to be analysed automatically, the accelerator, detection instruments and pneumatic transfer circuits being controlled
by a logic system linked to an electronic chronometer. 相似文献
109.
110.
Ohne Zusammenfassung 相似文献