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121.
We consider problems of the calculus of variations on unbounded time scales. We prove the validity of the Euler–Lagrange equation
on time scales for infinite horizon problems, and a new transversality condition. 相似文献
122.
Piotr Gwiazda Agnieszka Świerczewska-Gwiazda Petra Wittbold Aleksandra Zimmermann 《Journal of Functional Analysis》2014
We consider scalar balance laws with a dissipative source term. The flux function may be discontinuous with respect to both the space variable x and the unknown quantity u. We formulate the definition of entropy weak solutions and provide existence and uniqueness to the considered problem. The problem is formulated in the framework of multi-valued mappings. The notion of entropy measure-valued solutions is used to prove the so-called contraction principle and comparison principle. 相似文献
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125.
Maria Chrzanowska Agnieszka Grajewska Zofia Meissner Maria Rozwadowska Iwona Wiatrowska 《Tetrahedron》2012,68(14):3092-3097
A sequence of two reactions: the Petasis reaction, in which an aminoacetaldehyde acetal was used as the amine component, followed by Pomeranz–Fritsch–Bobbitt cyclization, has been shown to be a convenient and simple method for the synthesis of tetrahydroisoquinoline-1-carboxylic acids. Using this method several acids have been prepared in good to excellent yields and characterized as hydrochloride salts. 相似文献
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Agnieszka Górska Halina Hajmowicz Tomasz Kliś Janusz Serwatowski Ludwik Synoradzki 《应用有机金属化学》2011,25(4):294-297
The reaction of arylboronic acids with L ‐O‐benzoyl‐tartaric acid and D ,L ‐malic acid has been studied. The obtained (acyloxy)boranes are moderately stable in solution and decompose to give boroxines. 5‐Carboxymethyl‐2‐(4‐methylthiophenyl)‐1,3,2‐dioxaborolan‐4‐one was obtained in the reaction of 4‐methylthiophenylboronic acid with D ,L ‐malic acid and characterized by X‐ray structural analysis. The use of L ‐(−)‐malic acid afforded the optically pure product which can be used as the powerful chiral reagent in the enantioselective reduction of ketones. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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129.
Anca Peter Leonard Mihaly-Cozmuta Anca Mihaly-Cozmuta Camelia Nicula Agnieszka Jastrzębska Patrycja Kurtycz Andrzej Olszyna 《Chemical Papers》2015,69(6):839-855
Two types of graphene oxide-TiO2 composites were prepared: one by including graphene oxide flakes in the TiO2 sol, followed by thermal treatment (GI composite) at 300°C, and the second by including graphene oxide flakes in the calcined (at 500°C) TiO2 xerogel (GII composite). The composites were characterized by SEM, TEM-EDS, TEM-SADP, STEM-HAADF, HRTEM coupled with FT, XRD, and XPS. Photocatalysis results were fitted to different kinetic models (pseudo-first and pseudo-second kinetics, intraparticle Weber-Morris diffusion, film diffusion, and external mass transfer). The results showed that by introducing graphene oxide flakes in the TiO2 sol, followed by thermal treatment at 300°C (GI composite), an efficient graphene oxide-TiO2 catalyst with high specific surface area, heterogeneity, and many graphitized areas can be obtained. Complete crystallization of the composite is not the key issue for the best photoactivity achievement. The rate limiting step in the photocatalytic process is the photooxidation of SA molecules on the TiO2 surface. 相似文献
130.
Moxifloxacin is a representative of the fourth generation of fluoroquinolones. It possesses bacteriostatic activity against Gram-positive and Gram-negative bacteria. A simple and fast high performance liquid chromatography-ultraviolet detection (HPLC-UV) method was developed for moxifloxacin analysis. The separation was performed on C18 column. The mobile phase was a mixture of acetonitrile and 0.4% triethylamine solution. The regression curve was linear over the range 0.2–10.0?µg/mL. The validation parameters obey the European Medicine Agency limits. The in vivo study confirmed the practical application of the method. 相似文献