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961.
Oleg Ya. Borbulevych Igor R. Golding Alexander N. Shchegolikhin Zinaida S. Klemenkova Mikhail Yu. Antipin 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(8):996-998
Although the two polymorphic modifications, (I) and (II), of the title compound, C13H10N2O, crystallize in the same space group (P21/c), their asymmetric units have Z′ values of 1 and 2, respectively. These are conformational polymorphs, since the molecules in phases (I) and (II) adopt different rotations of the phenyl ring with respect the central 2‐cyanocarboxyaminoprop‐2‐enyl fragment. Calculations of crystal packing using Cerius2 [Molecular Simulations (1999). 9685 Scranton Road, San Diego, CA 92121, USA] have shown that (I) is more stable than (II), by 1.3 kcal mol?1 for the crystallographically determined structures and by 1.56 kcal mol?1 for the optimized structures (1 kcal mol?1 = 4.184 kJ mol?1). This difference is mainly attributed to the different strengths of the hydrogen bonding in the two forms. 相似文献
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Igor Yu. Popov Ilya V. Makeev 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2014,65(2):339-348
Two-dimensional Stokes flow in a half plane with coupled cavity having the form of semi-ellipse is considered. The exact solution for the boundary problem is obtained. The solution can be a benchmark for numerical approaches. An example of the benchmarking is given. 相似文献
965.
For porous media equations with a Radon measure on the right-hand side, we derive pointwise estimates for solutions via the Riesz potentials. 相似文献
966.
Igor Perevyazko Antje Vollrath Stephanie Hornig Georges M. Pavlov Ulrich S. Schubert 《Journal of polymer science. Part A, Polymer chemistry》2010,48(18):3924-3931
Nanoprecipitation represents an effective method for the production of polymeric nanoparticles. This technique was used to prepare nanoparticles from solutions of poly(methyl methacrylate) and its copolymers. Since the regulation of main parameters like particle size, particle size distribution, and molar particle mass is very important for future applications, the stable nanoparticle dispersions were examined by scanning electron microscopy, velocity sedimentation, and dynamic light scattering, whereby advantages and disadvantages of each characterization techniques are discussed. Polydispersities of particle size distributions are determined by the ratio of dw/dn, where dw and dn are weight‐ and number‐average diameters, respectively. The particle characteristics strongly depend on the chemical structure of the polymers and the way of preparation and, therefore, vary in the studied cases in the range of 6 < dw < 680 nm, whereas the polydispersity index dw/dn changes in the range of 1.02 to 1.40. It is shown that nanoparticles in a desirable size range can be prepared by solvent–nonsolvent methods (dialysis technique or dropping technique). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3924–3931, 2010 相似文献
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Optical and Quantum Electronics - A time-domain model of an excited semiconductor medium as a moving Bragg grating was used to investigate a double-Doppler wavelength conversion of an infrared... 相似文献
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Dr. Dmitry S. Perekalin Dr. Valentin V. Novikov Alexander A. Pavlov Igor A. Ivanov Dr. Natalia Yu. Anisimova Alexey N. Kopylov Dr. Dmitry S. Volkov Dr. Irina F. Seregina Prof. Dr. Michail A. Bolshov Prof. Dr. Alexander R. Kudinov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):4923-4925
Melittin is a membrane‐active peptide from bee venom with promising antimicrobial and anticancer activity. Herein we report on a simple and selective method for labeling of the tryptophan residue in melittin by the organometallic fragment [(C5H5)Ru]+ in aqueous solution and in air. Ruthenium coordination does not disturb the secondary structure of the peptide (as verified by 2D NMR spectroscopy), but changes the pattern of its intermolecular interactions resulting in an 11‐fold decrease of hemolytic activity. The high stability of the organometallic conjugate allowed the establishment of the biodistribution of the labeled melittin in mice by inductively coupled plasma MS analysis of ruthenium. 相似文献